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Wyszukujesz frazę "Zhang, Sun" wg kryterium: Autor


Tytuł:
Pressure Induced Transitions in Heavy-Fermion Systems footnotemark
Autorzy:
Zhang, Sun
Dong, Yi-Qiao
Powiązania:
https://bibliotekanauki.pl/articles/1401900.pdf
Data publikacji:
2015-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Mb
75.20.Hr
71.28.+d
74.62.Fj
Opis:
In this paper, the electron-type heavy-fermion system and the hole-type heavy-fermion system are classified by means of the cell-volume difference between two typical valence states of f ions. Two kinds of transitions induced by pressure are studied theoretically within a unified picture presented for both two types of heavy-fermion systems. Among these transitions, the incoherence-to-coherence transition in the electron-type heavy-fermion system is confirmed intensively in experiments, while the coherence-to-incoherence transition in the hole-type heavy-fermion system is discussed as a prediction for further observations.
Źródło:
Acta Physica Polonica A; 2015, 128, 3; 389-393
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shakespeare across the Taiwan Strait: A Developmental Perspective
Autorzy:
Sun, Yu
Zhang, Longhai
Powiązania:
https://bibliotekanauki.pl/articles/648254.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
Shakespeare Studies
China
Mainland
Taiwan
Shake-xiqu
Opis:
Shakespeare studies in Mainland China and Taiwan evolved from the same origin during the two centuries after Shakespeare being introduced into China in the early nineteenth century. Although Shakespeare was first seen on the Taiwan stage in the Japanese language during the colonial period, it was after Kuomintang moved to Taiwan in 1949 that Shakespeare studies began to flourish when scholars and theatrical experts from mainland China, such as Liang Shih-Chiu, Yu Er-Chang, Wang Sheng-shan and others brought Chinese Shakespeare to Taiwan. Since the 1980s, mainland Shakespeareans began to communicate actively with their colleagues in Taiwan. With the continuous efforts of Cao Yu, Fang Ping, Meng Xianqiang, Gu Zhengkun, Yang Lingui and many other scholars in mainland China and Chu Li-Min, Yen Yuan-shu, Perng Ching-Hsi and other scholars in Taiwan, communications and conversations on Shakespeare studies across the Taiwan Strait were gradually enhanced in recent years. Meanwhile, innovations in Chinese adaptations of Shakespeare have resulted in a new performing medium, Shake-xiqu, through which theatrical practitioners on both sides explore possibilities of a union of Shakespeare and traditional Chinese theatre. This paper studies some intricate relationship in the history of Shakespeare studies in mainland China and Taiwan from a developmental perspective and suggests opportunities for positive and effective co-operations and interactions in the future.
Źródło:
Multicultural Shakespeare: Translation, Appropriation and Performance; 2019, 20, 35; 115-131
2083-8530
2300-7605
Pojawia się w:
Multicultural Shakespeare: Translation, Appropriation and Performance
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Autothermal Reforming of Diesel Oil for PdCeCrFeCu/Al2O3-Catalyzed Hydrogen Production
Autorzy:
Lin, Lin
Zhang, Kai
Sun, Chiyu
Zhang, Ying
Powiązania:
https://bibliotekanauki.pl/articles/1849270.pdf
Data publikacji:
2021
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
diesel
reform
hydrogen
catalyst
Opis:
To make clear the feasibility and influence factors of diesel fuel autothermal reforming to hydrogen, PdCeCr-FeCu/Al2O3 catalyst was prepared by equivalent-volume impregnation method. Experimental facility based on an adiabatic tubular reactor with preheating section was designed and set up, the behaviors of diesel reforming to hydrogen with straight-run diesel as a raw material according to the analysis of the components were studied. Diesel oil reforming over a catalyst for hydrogen production was analyzed using an adiabatic tubular reactor with a preheating section that was designed and built in-house. The operating conditions were optimized. Under the suitable operating conditions, viz., catalyst bed inlet temperature of 700°C, diesel liquid space velocity of 0.24 h–1, water-carbon ratio of 20, and oxygen-carbon ratio of 0.6, the hydrogen yield reached 28.3 (mol/mol).
Źródło:
Polish Journal of Chemical Technology; 2021, 23, 2; 12-19
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Autothermal Reforming of Diesel Oil for PdCeCrFeCu/Al2O3-Catalyzed Hydrogen Production
Autorzy:
Lin, Lin
Zhang, Kai
Sun, Chiyu
Zhang, Ying
Powiązania:
https://bibliotekanauki.pl/articles/1849272.pdf
Data publikacji:
2021
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
diesel
reform
hydrogen
catalyst
Źródło:
Polish Journal of Chemical Technology; 2021, 23, 2; 12-19
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Autothermal Reforming of Diesel Oil for PdCeCrFeCu/Al2O3-Catalyzed Hydrogen Production
Autorzy:
Lin, Lin
Zhang, Kai
Sun, Chiyu
Zhang, Ying
Powiązania:
https://bibliotekanauki.pl/articles/1849267.pdf
Data publikacji:
2021
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
diesel
reform
hydrogen
catalyst
Opis:
To make clear the feasibility and influence factors of diesel fuel autothermal reforming to hydrogen, PdCeCr-FeCu/Al2O3 catalyst was prepared by equivalent-volume impregnation method. Experimental facility based on an adiabatic tubular reactor with preheating section was designed and set up, the behaviors of diesel reforming to hydrogen with straight-run diesel as a raw material according to the analysis of the components were studied. Diesel oil reforming over a catalyst for hydrogen production was analyzed using an adiabatic tubular reactor with a preheating section that was designed and built in-house. The operating conditions were optimized. Under the suitable operating conditions, viz., catalyst bed inlet temperature of 700°C, diesel liquid space velocity of 0.24 h–1, water-carbon ratio of 20, and oxygen-carbon ratio of 0.6, the hydrogen yield reached 28.3 (mol/mol).
Źródło:
Polish Journal of Chemical Technology; 2021, 23, 2; 12-19
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reliability based analysis and design of a tripod offshore wind turbine structure assuring serviceability performance
Autorzy:
Zhang, J.
Kang, W. H.
Zhang, C.
Sun, K.
Powiązania:
https://bibliotekanauki.pl/articles/259493.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
offshore wind turbine
tripod foundation
serviceability limit state
statistical correlation analysis
reliability analysis
Opis:
Typical tripod foundations are designed using deterministic computational models according to relevant standards and codes. However, for more cost-safety balanced design, uncertainties in significant parameters should be considered in preliminary design to ensure meeting a specific probabilistic safety target in the context of the complex configuration of a tripod structure. In this article, uncertainties associated with design parameters and modelling errors are considered using Monte Carlo simulations, in order to determine the key structural design parameters, and to determine the optimal balance between design parameters and design requirements. A Spearman rank-order correlation based analysis is carried out to understand the effects of design variables on maximum deformation, total weight, and natural frequency, and to have insight about important design parameters for improvement of a preliminary design. It is found that the tower diameter has the most significant effect on the maximum displacement on the hub as validated through engineering case studies. In addition, a statistical framework, which identifies influential design parameters and provides reliability evaluation, is proposed for the structural design of a tripod OWT system. The design cases considered in this study indicate that a simple deterministic design check cannot guarantee the required reliability level of the structure, and the cost-safety balance can be achieved by a reliability analysis with the consideration of the uncertainties in the structure.
Źródło:
Polish Maritime Research; 2018, 4; 139-148
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel multi-objective discrete particle swarm optimization with elitist perturbation for reconfiguration of ship power system
Autorzy:
Zhang, L.
Sun, J.
Guo, C.
Powiązania:
https://bibliotekanauki.pl/articles/260215.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
shipboard power system
reconfiguration
multi-objective
discrete PSO
elitist perturbation
Opis:
A novel multi-objective discrete particle swarm optimization with elitist perturbation strategy (EPSMODPSO) is proposed and applied to solve the reconfiguration problem of shipboard power system(SPS). The new algorithm uses the velocity to decide each particle to move one step toward positive or negative direction to update the position. An elitist perturbation strategy is proposed to improve the local search ability of the algorithm. Reconfiguration model of SPS is established with multiple objectives, and an inherent homogeneity index is adopted as the auxiliary estimating index. Test results of examples show that the proposed EPSMODPSO performs excellent in terms of diversity and convergence of the obtained Pareto optimal front. It is competent to solve network reconfiguration of shipboard power system and other multi-objective discrete optimization problems.
Źródło:
Polish Maritime Research; 2017, S 3; 79-85
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Auxiliary intelligent operating system for dragline stripping equipment in surface mining
Autorzy:
Sun, J.-D.
Zhang, R.-X.
Powiązania:
https://bibliotekanauki.pl/articles/88889.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
dragline stripping
intelligent operating system
operational efficiency
Opis:
In order to improve operation skill of the operators, the design of the auxiliary intelligent operating system of the dragline was studied. Whereby the gyroscopes incorporated in smartphone and data sequence filter algorithm, the automatic collection function of operation cycle, the rotation angle and other parameters of the dragline are attained. In line with the relations among the rotation angle of equipment operation, time-spent and the acceleration, the ratio of the acceleration and deceleration rotation angle in full load rotation and non-loaded return stage are acquired respectively. The function of bucket in rotation was realized. Comprehensive score calculation standard of the technique level of the dragline-based operation was developed, and the function of automatic checking the operation level was effectuated. Field experiment results indicated that the operators’ faults are markedly reduced as the auxiliary intelligent operating system is employed. By using the system the operation behavior of low power slow rotation in rain, snow, low atmospheric pressure and other severe weather conditions can be reduced, assuring all-weather efficient and safe operation of dragline.
Źródło:
Mining Science; 2017, 24; 251-266
2300-9586
2353-5423
Pojawia się w:
Mining Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research and application of rule updating mining algorithm for marine water quality monitoring data
Autorzy:
Sun, Q
Zhang, J.
Xu, X
Powiązania:
https://bibliotekanauki.pl/articles/258822.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine water quality monitoring
database updating
data mining
rule updating
Opis:
This paper studies the characteristics of marine water quality monitoring data monitored by photoelectric sensor network, mines the potential information from the massive data. on account of the continuous accumulation of monitoring data, this paper focuses on the study of database with numerical attribute and proposes a rule updating algorithm for solving the rule maintenance issues caused by changes in the database. according to the rule, the algorithm forms a new database from part of the original data and the new data, and searches the new database by random search, thus can avoid creating a large number of redundant rules and can quickly mine effective rules at the same time. experimental results show that this method not only can avoid mining in the whole original massive data, but also can improve work efficiency, and can quickly and effectively find new data and find useful rules in the data with high practicability.
Źródło:
Polish Maritime Research; 2018, S 3; 136-140
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heating control of heated twin radiosonde humidity sensor based on DMC
Autorzy:
Sun, N.
Zhang, Y.
Zhang, W
Cheng, E.
Liu, Y.
Powiązania:
https://bibliotekanauki.pl/articles/260018.pdf
Data publikacji:
2016
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
DMC
twin heated humidity sensor
expanded responsible curve
heating control
Opis:
In order to effectively solve condensation and icing problems of radiosonde in low-temperature environment at high altitude, humidity sensor heated automatic alternately to remove pollution and improve the measurement accuracy. Heat experiments obtained the curve of rising temperature and responsible time on heated twin humidity sensor in normal temperature and pressure, by expanded responsible curve to obtain heated model of twin heated humidity sensor and by the analysis of heating model, use DMC and PID control for heating respectively. Simulation results show that the DMC control meets the practical requirements of measure at high altitude.
Źródło:
Polish Maritime Research; 2016, S 1; 52-58
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
pVAX1 plasmid vector-mediated gene transfer of soluble TRAIL suppresses human hepatocellular carcinoma growth in nude mice
Autorzy:
Zhang, Yan
Ma, Cun
Liu, Hua
Zhang, Xiu
Sun, Wen
Powiązania:
https://bibliotekanauki.pl/articles/1041078.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
pVAX1
soluble TRAIL
naked DNA
gene therapy
hepatocellular carcinoma
Opis:
The extracellular domain of the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) may function as a soluble cytokine to selectively kill various cancer cells without toxicity to most normal cells. We used a high-biosafety plasmid pVAX1 as a vector and constructed a recombinant plasmid expressing the extracellular domain (95-281 aa) of human TRAIL fused with signal peptides of human IgGγ, designated as pVAX-sT. Transduction of human BEL7402 liver cancer cells with pVAX-sT led to high levels of sTRAIL protein in the cell culture media and induced apoptosis. The therapeutic potential of pVAX-sT was then evaluated in the BEL7402 transplanted naked mouse model. Subsequent intratumoral administration of naked pVAX-sT resulted in the expression of soluble TRAIL in the sera and the tumor site, as well as effective suppression of tumor growth, with no toxicity to liver. In conclusion, the successful inhibition of liver cancer growth and the absence of detectable toxicity suggest that pVAX-sT could be useful in the gene therapy of liver cancer.
Źródło:
Acta Biochimica Polonica; 2007, 54, 2; 307-313
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental study on the joint application of innovative techniques for the improved drivage of roadways at depths over 1 km: a case study
Autorzy:
Zhang, Wei
Tang, Jia-Jia
Zhang, Dong-Sheng
Zhang, Lei
Sun, Yuyan
Zhang, Wei-Sheng
Powiązania:
https://bibliotekanauki.pl/articles/219958.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
pomiar naprężeń
wiercenie
piaskowanie
odkształcenie
roadways at depth over 1 km
in-situ stress measurements
efficient drivage
rapid drilling and blasting
deformation control of SRR
industrial test
Opis:
Finding effective ways to efficiently drive roadways at depths over 1 km has become a hotspot research issue in the field of mining engineering. In this study, based on the local geological conditions in the Xinwen Mining Area (XMA) of China, in-situ stress measurements were conducted in 15 representative deep roadways, which revealed the overall tectonic stress field pattern, with the domination of the horizontal principal stresses. The latter values reached as high as 42.19 MPa, posing a significant challenge to the drivage work. Given this, a comprehensive set of innovative techniques for efficiently driving roadways at depths over 1 km was developed, including (i) controlled blasting with bidirectional energy focusing for directional fracturing, (ii) controlled blasting with multidirectional energy distribution for efficient rock fragmentation, (iii) wedge-cylinder duplex cuts centered on double empty holes, and (iv) high-strength supports for deep roadways. The proposed set of techniques was successfully implemented in the –1010 west rock roadway (WRR) drivage at the Huafeng Coal Mine (HCM). The improved drivage efficiency was characterized by the average and maximum monthly advances of 125 and 151 m, respectively. The roadway cross-sectional shape accuracy was also significantly improved, with the overbreak and underbreak zones being less than 50 mm. The deformation in the surrounding rock of roadway (SRR) was adequately controlled, thus avoiding repeated maintenance and repair. The relevant research results can provide technical guidance for efficient drivage of roadways at depths over 1 km in other mining areas in China and worldwide.
Źródło:
Archives of Mining Sciences; 2020, 65, 1; 159-178
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimal control strategy for marine SSP podded propulsion motor based on strong tracking-EPF
Autorzy:
Yao, W.
Liu, Y.
Sun, H.
Zhang, G.
Zhang, J.
Zhou, M.
Sun, M.
Jiang, D.
Powiązania:
https://bibliotekanauki.pl/articles/258784.pdf
Data publikacji:
2015
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine electric propulsion
EPF
ST-EPF
SSP podded propulsion
propulsion motor
Opis:
Aiming at the non-linearity of state equation and observation equation of SSP (Siemen Schottel Propulsor) propulsion motor, an improved particle filter algorithm based on strong tracking extent Kalman filter (ST-EKF) was presented, and it was imported into the marine SSP propulsion motor control system. The strong tracking filter was used to update particles in the new algorithm and produce importance densities. As a result, the problems of particle degeneracy and sample impoverishment were ameliorated, the propulsion motor states and the rotor resistance were estimated simultaneously using strong track filter (STF), and the tracking ability of marine SSP propulsion motor control system was improved. Simulation result shown that the improved EPF algorithm was not only improving the prediction accuracy of the motor states and the rotor resistance, but also it can satisfy the requirement of navigation in harbor. It had the better accuracy than EPF algorithm.
Źródło:
Polish Maritime Research; 2015, S 1; 4-9
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synchronization Study and Introductory Experiment οf Laser-Triggered Surface Flashover in Voltage Pulse
Autorzy:
Pan, R.
Wang, J.
Sun, Y.
Sun, G.
Yan, P.
Zhang, D.
Powiązania:
https://bibliotekanauki.pl/articles/1807974.pdf
Data publikacji:
2009-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
52.80.-s
51.50.+v
Opis:
With the aim of studying the characteristics of laser-triggered surface flashover in voltage pulse, synchronization problem of laser pulse and voltage pulse should be solved. A single/double harmonic, with wavelength λ of 1064/532 nm, Q-switched Nd:YAG laser is used to trigger the surface flashover. The synchronization problem is solved using a self-made digital delay/pulse generator. The delay time and jitter of Marx's trigger input and output, Marx's trigger output and Marx's output, laser input and output are respectively measured. Based on the result of the delay time and the timing sequence of the laser triggering system, the synchronization of laser pulse and voltage pulse is obtained through adjusting the channel delay time of digital delay/pulse generator. In addition, introductory experiment of laser-triggered surface flashover is carried out using the flat electrodes and columned insulators.
Źródło:
Acta Physica Polonica A; 2009, 115, 6; 1167-1169
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optymalizacja zależnego od stanu technicznego utrzymania urządzeń dla dwuskładnikowego systemu szeregowego nie wymagająca z góry ustalonej struktury strategii
Condition-based Maintenance Optimisation without a Predetermined Strategy Structure for a Two-component Series System
Autorzy:
Zhang, Z.
Zhou, Y.
Sun, Y.
Ma, L.
Powiązania:
https://bibliotekanauki.pl/articles/301595.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
semimarkowski proces decyzyjny
condition-based maintenance
system wieloskładnikowy
semi-Markov decision process
multi-component system
Opis:
Większość badań nad optymalizacją utrzymania systemów wieloskładnikowych bierze pod uwagę jedynie rozkład czasu życia elementów składowych. Kiedy przyjmie się dla systemów wieloskładnikowych strategię utrzymania urządzeń zależną od ich bieżącego stanu technicznego (condition-based maintenance, CBM), struktura strategii staje się złożona w związku z dużą liczbą stanów składowych oraz ich kombinacji. W konsekwencji, często przyjmuje się pewne z góry ustalone struktury strategii utrzymania przed optymalizacją utrzymania systemu wieloskładnikowego w kontekście CBM. Opracowanie takich z góry ustalonych struktur strategii wymaga jednak specjalistycznego doświadczenia, a i tak brak dowodów na optymalność tych strategii. W artykule zaproponowano metodę optymalizacji utrzymania szeregowego systemu dwuskładnikowego, która nie wymaga wcześniej ustalonej struktury strategii. Proponowaną metodę opracowano na podstawie semimarkowskiego procesu decyzyjnego (SMDP). Badanie symulacyjne pokazało, że za pomocą proponowanej metody można ustalać optymalną strategię utrzymania w sposób adaptacyjny dla różnych kosztów utrzymania oraz parametrów procesów degradacyjnych. Za pomocą symulacji badano także optymalną strukturę strategii utrzymania, jako punkt odniesienia dla przyszłych studiów nad optymalizacją systemów wieloskładnikowych.
Most existing research on maintenance optimisation for multi-component systems only considers the lifetime distribution of the components. When the condition-based maintenance (CBM) strategy is adopted for multi-component systems, the strategy structure becomes complex due to the large number of component states and their combinations. Consequently, some predetermined maintenance strategy structures are often assumed before the maintenance optimisation of a multicomponent system in a CBM context. Developing these predetermined strategy structure needs expert experience and the optimality of these strategies is often not proofed. This paper proposed a maintenance optimisation method that does not require any predetermined strategy structure for a two-component series system. The proposed method is developed based on the semi-Markov decision process (SMDP). A simulation study shows that the proposed method can identify the optimal maintenance strategy adaptively for different maintenance costs and parameters of degradation processes. The optimal maintenance strategy structure is also investigated in the simulation study, which provides reference for further research in maintenance optimisation of multi-component systems.
Źródło:
Eksploatacja i Niezawodność; 2012, 14, 2; 120-129
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Utility optimization-based bandwidth allocation for elastic and inelastic services in peer-to-peer networks
Autorzy:
Li, Shiyong
Zhang, Yue
Wang, Yan
Sun, Wei
Powiązania:
https://bibliotekanauki.pl/articles/330690.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
peer-to-peer network
bandwidth allocation
elastic services
inelastic services
utility function
sieć peer-to-peer
alokacja przepustowości
funkcja użyteczności
Opis:
This paper considers reasonable bandwidth allocation for multiclass services in peer-to-peer (P2P) networks, measures the satisfaction of each peer as a customer by a utility function when acquiring one service, and develops an optimization model for bandwidth allocation with the objective of utility maximization. Elastic services with concave utilities are first considered and the exact expression of optimal bandwidth allocation for each peer is deduced. In order to obtain an optimum in distributed P2P networks, we develop a gradient-based bandwidth allocation scheme and illustrate the performance with numerical examples. Then we investigate bandwidth allocation for inelastic services with sigmoidal utilities, which is a nonconvex optimization problem. In order to solve it, we analyze provider capacity provisioning for bandwidth allocation of inelastic services and modify the update rule for prices that service customers should pay. Numerical examples are finally given to illustrate that the improved scheme can also efficiently converge to the global optimum.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2019, 29, 1; 111-123
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel lectin with antiproliferative activity from the medicinal mushroom Pholiota adiposa
Autorzy:
Zhang, G.
Sun, J.
Wang, H.
Ng, T.
Powiązania:
https://bibliotekanauki.pl/articles/1040531.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Pholiota adiposa
lectin
mushroom
purification
antiproliferative
Opis:
Little was known about biological activities of compounds from the medicinal mushroom of the genus Pholiota. A lectin from the Pholiota adiposa has now been isolated and its properties tested. The isolation procedure included ion exchange chromatography on DEAE-cellulose and CM-cellulose, and fast protein liquid chromatography-gel filtration (FPLC) on Superdex 75. The lectin was composed of two identical subunits, each with a molecular mass of 16 kDa. Its N-terminal amino-acid sequence showed little similarity to sequences of other Agaricales lectins. The hemagglutinating activity of the lectin was stable at temperatures up to 50°C, and in NaOH and HCl solutions with concentrations less than 25 mM. It was inhibited by inulin (12.5-200 mM), but enhanced by Cu2+ (6.25-25 mM), Fe2+ (12.5-25 mM), and Al3+ (6.25-25 mM) ions. The lectin showed antiproliferative activity toward hepatoma Hep G2 cells and breast cancer MCF7 cells with an IC50 of 2.1 µM and approximately 3.2 µM, respectively. It exhibited HIV-1 reverse transcriptase inhibitory activity with an IC50 of 1.9 µM. When compared with P. aurivella lectin, the only Pholiota lectin published to date, P. adiposa lectin differs in chromatographic behavior, molecular mass, N-terminal sequence, and effect of cations on hemagglutinating activity. In the case of the lectin from P. aurivella, its antifungal, antiproliferative, and HIV-1 reverse transcriptase inhibitory activities have not been determined.
Źródło:
Acta Biochimica Polonica; 2009, 56, 3; 415-421
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The American Lawn Revisited: Awareness Education and Culture as Public Policies Toward Sustainable Lawn
Amerykańskie trawniki z bliska: świadomość, edukacja i kultura jako motywy polityki publicznej prowadzącej w kierunku zrównoważoności
Autorzy:
Zhang, Y.
Zheng, B.
Sun, G.
Fan, P.
Powiązania:
https://bibliotekanauki.pl/articles/371741.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Komitet Człowiek i Środowisko PAN
Tematy:
grass
American culture
conspicuous consumption
industrialization
urbanization
pollution
aesthetics
landscaping
trawa
amerykańska kultura
demonstracyjna kultura
industrializacja
urbanizacja
zanieczyszczenie
estetyka
krajobraz
Opis:
Lawn has been used for landscaping, gardening, and beautification of homes and cities for a long time. The evolution of the lawn reflects important cultural and biophysical interactions between humans and nature. The American lawn, which was from Europe and has been a part of the American dream for home ownership and culture, has become an area going against nature for its extensively using chemicals and generated pollutions. Tracing how the lawn is becoming an important part of culture, this article focuses on more recent pollution and other environmental problems resulted from the lawn culture. It is argued, that awareness, education and changing culture of taste and preference can serve additional measures together with law and technological advancement toward sustainable lawn in the United States and the world.
Trawnik już o dawna był używany w kształtowaniu krajobrazu, ogrodnictwie i upiększaniu domów. Ewolucja trawników odzwierciedla istotne kulturowe i biofizyczne interakcje pomiędzy ludźmi i przyrodą. Trawnik trafił do Ameryki z Europy i stał się częścią amerykańskiego snu o własności i kulturze domu. Później stał się on jednak obszarem przeciwstawiającym się naturze z uwagi na intensywnie stosowanie substancji chemicznych i generowanie zanieczyszczeń. Wykazując, w jaki sposób trawnik staje się ważną częścią kultury, ten artykuł skupia się na bardziej aktualnych kwestiach zanieczyszczeń i innych problemów środowiskowych. Wykształcenie świadomości, zmieniającą się kultura smaku i preferencje, łącznie z prawem i technologią, mogą stanowić dodatkowe środki prowadzące w kierunku zrównoważonego kształtowania trawników w Stanach Zjednoczonych i na świecie.
Źródło:
Problemy Ekorozwoju; 2015, 10, 1; 107-115
1895-6912
Pojawia się w:
Problemy Ekorozwoju
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ecological Compensation Standard for Non-point Pollution from Farmland
Propozycja standardu ekologicznej kompensacji dla obszarowych zanieczyszczeń z rolnictwa
Autorzy:
Zhang, Y.
Ji, Y.
Zhou, Y.
Sun, H.
Powiązania:
https://bibliotekanauki.pl/articles/371753.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Komitet Człowiek i Środowisko PAN
Tematy:
ecological compensation standard
nitrogen
non-point pollution
optimal ecological economic nitrogen application amount
standard kompensacji ekologicznej
azot
obszarowe źródła zanieczyszczeń
optymalna ekologicznie ilość stosowanego azotu
Opis:
Non-point source water pollution mainly comes from farmland chemical fertilizers which has become an obstacle of agricultural sustainability and ecological health. As a public policy tool for assessing global ecological crisis and environmental pollution, ecological compensation is important for regional agricultural sustainability. Ecological compensation that farmers receive from governments is based on their reduction of fertilizer application at optimal ecological and economic levels. In this study we estimated the ecological compensation standards for nitrogen non-point pollution in Yixng city with contingent valuation method and cost-benefit method. Results showed that the range of theoretical values of ecological compensation of nitrogen in Yixing City depended upon its optimal ecological and economic nitrogen application levels. The willingness of farmers to accept the compensation was positively correlated with their farming experience and education. There were about half of farmers willing to accept the compensation. Based on the present study, we found Yixing’s ecological compensation standard for controlling nitrogen non-point pollution was 620.0 yuan/hm2 at the current economic development level.
Obszarowe zanieczyszczeń wód z rolnictwa pochodzą ze stosowania nawozów sztucznych, stanowiących prze-szkodę na drodze do osiągnięcia rolniczej zrównoważoności i równowagi ekologicznej. W tym kontekście ekologiczna kompensacja, stanowiąca narzędzie polityczne do oceny kryzysu ekologicznego i ogólnego poziomu zanieczyszczenia środowiska, okazuje się także ważna w wymiarze lokalnej zrównoważoności rolniczej. Wysokość świadczeń, które rolniczy dostają od władz, jest uwarunkowana poziomem redukcji stosowania nawozów, którego celem jest osiągnięcie poziomu optymalnego zarówno zer strony ekologicznej, jak i ekonomicznej. W tym artykule, przy pomocy Metoda wyceny warunkowej i metody kosztów i korzyści, ustaliliśmy standardy ekologicznej kompensacji dla miasta Yixng. Otrzymane rezultaty pozwalają na stwierdzenie, że zakres teoretycznych wartości ekologicznej kompensacji dla azotu w Yixing zależy od ustalenia optymalnych ekologicznych i ekonomicznych pozimów stosowania azotu. Zainteresowanie rolników otrzymaniem odszkodowania okazało się być pozytywnie skorelowane z ich doświadczeniem rolniczym i poziomem wykształcenia. Chęć jego otrzymania zgłosiła połowa z nich. Ustaliliśmy ponadto, że standard ekologicznej kompensacji dla Yixing odnoszący się kontrolowania ob-szarowych zanieczyszczeń związanych z nawozami azotowymi wynosi 620.0 yuan/hm2 , przy założeniu obecnego poziomu rozwoju ekonomicznego.
Źródło:
Problemy Ekorozwoju; 2017, 12, 1; 139-146
1895-6912
Pojawia się w:
Problemy Ekorozwoju
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New bizarre micro-spiriferid brachiopod from the Early Carboniferous of China
Autorzy:
Sun, Y
Balinski, A.
Ma, X.
Zhang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/22087.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Carboniferous
verneuiliid brachiopod
brachiopod
China
Muhua Formation
Verneuiliidae
Early Carboniferous
Brachiopoda
Changshunella yangi
paleontology
Opis:
The verneuiliid brachiopod Changshunella yangi gen. et sp. nov. is described from the Early Carboniferous Muhua Formation of Guizhou, China. This rather unusual form is characterized by having very small shell dimensions (2.6–4 mm in length), a very high flat procline ventral interarea, and by having three prominent plications on both valves that are arranged in opposed folding; the last feature is characteristic for the family Verneuiliidae. We suggest that the family has been derived from an offshoot of the stock that produced the superfamilies Spiriferoidea, Paeckelmanelloidea, and Brachythyridoidea by developing opposed folding and loss of dental plates or dental adminicula as exemplified by Verneuilia and Changshunella gen. nov.
Źródło:
Acta Palaeontologica Polonica; 2004, 49, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamic rating method of traction network based on wind speed prediction
Autorzy:
Su, Zhaoux
Tian, Mingxing
Sun, Lijun
Zhang, Ruopeng
Powiązania:
https://bibliotekanauki.pl/articles/2086724.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
dynamic thermal rating
IEEE-738
short-term emergency dispatch
time series model
traction power supply
wind speed prediction
Opis:
The operating temperature of the transmission line in the traction network is affected by geographical and climatic factors, especially the wind speed. To make better use of the thermal stability transmission capacity of the traction power supply system in improving the short-term emergency transmission capacity, the dynamic rating technology is introduced into the traction power supply system. According to the time-varying characteristics of the actual wind speed, a dynamic rating method of the traction network based on wind speed prediction is proposed and constructed. Based on the time series model in predicting the wind speed series along the corridor of the traction network, the temperature curve of each transmission line under different currents is calculated by combining it with the heat balance equation of an IEEE-738 capacity expansion model, thus the relationship between the peak operating temperature and current of each transmission line in the prediction period is obtained. According to the current distribution coefficient, the capacity increase limit of the traction network is determined. The example shows that the proposed dynamic rating method based on wind speed prediction is an effective method to predict the short-term safe capacity increase limit of the traction network, which can increase the comprehensive capacity of the traction network by about 45% in the next six hours, and the capacity increase effect is obvious, which can provide reference and technical support for short-term emergency dispatching of traction power supply dispatching centres.
Źródło:
Archives of Electrical Engineering; 2022, 71, 2; 379--395
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical bistability in double quantum dot molecule with inter-dot tunnelling
Autorzy:
Yu, Chunchao
Sun, Lihui
Zhang, Huafeng
Chen, Fang
Powiązania:
https://bibliotekanauki.pl/articles/174307.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
optical bistability
quantum dot molecule
tunneling
Opis:
We have theoretically studied the optical bistability behaviors under an external electric field and a coupling laser field in double quantum dot molecule system with π-type four energy levels. It can be adjusted by the system parameters such as the electronic cooperation parameter, the tunneling strength, the coupling laser field, the probe and coupling laser detuning. These results may be useful in the experiment and provide new types of all-optical switching.
Źródło:
Optica Applicata; 2019, 49, 2; 293-301
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enterprise digital transformation and debt financing cost in Chinas A-share listed companies
Autorzy:
Sun, Changling
Zhang, Zixi
Vochozka, Marek
Vozňáková, Iveta
Powiązania:
https://bibliotekanauki.pl/articles/19322603.pdf
Data publikacji:
2022
Wydawca:
Instytut Badań Gospodarczych
Tematy:
digital transformation
digital economy
debt financing cost
information asymmetry
agency problem
Opis:
Research background: The rapid development of digital economy has set off a new wave of enterprise reform. Developing the digital economy is not only an urgent requirement of the current situation, but also an important way to meet the people's better life. Purpose of the article: This paper attempts to reveal the important role of the development of digital technology on the debt financing cost of micro enterprises, and provide micro evidence for the integration of digital economy and real economy. At the same time, this paper wants to provide relevant guidance for formulating digital related policies and reducing the financing cost of the real economy. Methods: Taking China's A-share listed companies from 2007 to 2020 as a sample, this paper empirically tests the impact of enterprise digital transformation on debt financing cost and its mechanism. In the robustness test, this paper uses the measures of changing independent variables and dependent variables, instrumental variable method and quantile regression method. In the mechanism test, this paper uses the intermediary effect model. In the further study, this paper uses the method of group regression. Findings & value added: The study finds that the digital transformation of enterprises significantly reduces the cost of debt financing. Mechanism tests show that the role of enterprise digital transformation in reducing debt financing costs is mainly realized by reducing information asymmetry and alleviating agency problems. Further tests show that the relationship between enterprise digital transformation and debt financing cost is affected by the degree of market competition, whether it is a high-tech enterprise and audit quality. When the degree of market competition is high, the enterprise is a high-tech one, or it is audited by the four major international accounting firms, the effect of enterprise digital transformation on the reduction of debt financing cost is more significant. The method used in this paper is also applicable to the study of other economic management problems. This paper proves a positive significance of digital transformation, which is conducive to promoting the digital transformation of enterprises. Especially for those enterprises in non-high-tech industries, they should speed up the pace. At the same time, this paper has a certain guiding role for the introduction and implementation of policies to encourage digital transformation.
Źródło:
Oeconomia Copernicana; 2022, 13, 3; 783-829
2083-1277
Pojawia się w:
Oeconomia Copernicana
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A combinatorial auction mechanism for time-varying multidimensional resource allocation and pricing in fog computing
Autorzy:
Li, Shiyong
Zhang, Yanan
Sun, Wei
Liu, Jia
Powiązania:
https://bibliotekanauki.pl/articles/15548021.pdf
Data publikacji:
2023
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
fog computing
combinatorial auction
time varying multidimensional resource allocation
resource pricing
mgła obliczeniowa
aukcja kombinatoryczna
wycena zasobów
Opis:
It is a hot topic to investigate resource allocation in fog computing. However, currently resource allocation in fog computing mostly supports only fixed resources, that is, the resource requirements of users are satisfied with a fixed amount of resources during the usage time, which may result in low utility of resource providers and even cause a waste of resources. Therefore, we establish an integer programming model for the time-varying multidimensional resource allocation problem in fog computing to maximize the utility of the fog resource pool. We also design a heuristic algorithm to approximate the solution of the model. We apply a dominant-resource-based strategy for resource allocation to improve resource utilization as well as critical value theory for resource pricing to enhance the utility of the fog resource pool. We also prove that the algorithm satisfies truthful and individual rationality. Finally, we give some numerical examples to demonstrate the performance of the algorithm. Compared with existing studies, our approach can improve resource utilization and maximize the utility of the fog resource pool.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2023, 33, 2; 327--339
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermodynamic analysis of hybrid ceramic bearings with metal inner rings
Autorzy:
Sun, Jian
Zhang, Gungxiang
Tian, Junxing
Zhu, Yusheng
Powiązania:
https://bibliotekanauki.pl/articles/27312210.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
hybrid ceramic bearing
silicon nitride
inner ring metal
bearing temperature rise
Opis:
For the sake of exploring the thermodynamic characteristics of hybrid ceramic bearings with metal inner rings in the application process, we established the mathematical model of bearings with metal inner rings based on the thermodynamics of bearings. The heat of the bearings, inner and outer raceway, and the deformation of bearings were calculated by the thermodynamic model. We used the bearing life testing machine to test the bearing load and speed. The consequences indicate that the temperature stability time of a hybrid ceramic bearing with the metal inner ring is about 6 hours after loading, and its temperature is about 1–2◦C higher than that of a metal bearing. Under the condition of a certain speed, the stable temperature of bearing operation improves with the enlargement of the load. Under the condition of a certain load, the bearing temperature also improves with the enlargement of bearing speed. The overall temperature trend of the bearing outer ring is unanimous with the overall temperature value calculated by the model. The maximum error is between 2.2 and 2.4◦C. The thermodynamic analysis of hybrid bearings with metal inner rings is conducive to a better study of the effect of bearing material characteristics on bearing performance.
Źródło:
Archives of Thermodynamics; 2023, 44, 3; 83--98
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Functional traits related to environmental divergence in combination with phylogenetic relationship of Picea species
Autorzy:
Wang, M.
Wang, J.
Zhang, A.
Zhang, X.
Sun, S.
Zhao, C.
Powiązania:
https://bibliotekanauki.pl/articles/2077949.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
δ13C
P50
Picea
seeva
quantitative convergence index
Opis:
Background: Plants have adapted to fine-scale environmental heterogeneity through ecologically important traits, leading to new lineages. This suggests that differentiation of important traits has been beneficial to habitat partitioning among closely related species. However, the pattern of ecological divergences and differentiation of functional traits in combination with phylogenetic relationships have not been widely examined. Material and methods: To illustrate the pattern of ecological divergences of nine Picea species, spatial evolutionary and ecological vicariance analysis (seeva) was used to quantify and test the divergence between sister lineages. Five functional traits were measured in a common garden experiment. For all traits the quantitative convergence index (QVI) was determined. Furthermore, their relationships with divergent environmental variables were analyzed in the context of phylogenetic relationships. Results: Temperature variables (maximum temperature of warmest month and temperature annual range) split at basal nodes and precipitation variables (annual precipitation and precipitation of driest quarter) split at terminal nodes. Conservative traits were leaf mass per area (LMA) and net photosynthetic rate (Pn), which reflected selective retention when ancestors suffered cold environmental separation. Meanwhile, linear stomatal density (LSD), carbon-13 isotope ratio (δ13C) and water potential at 50% loss of hydraulic conductivity (P50) were convergent between species, but only P50 exhibited adaption to different precipitation conditions. The nine Picea species exhibit a distinct environmental divergence pattern. LMA and Pn were selectively retained when their ancestors were subjected to cold environmental separation. P50 was an important trait with respect to adaptation to precipitation differences. This research provided a new way of expounding the correlation between environment, functional traits and phylogeny, deepening our understanding of environmental divergence, trait differentiation and speciation.
Źródło:
Dendrobiology; 2018, 80; 131-142
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis on the influence factor of low-strength wet shotcrete in frigid mining area
Autorzy:
Sun, Wei
Shengyou, Zhang
Feng, Xinglong
Hou, Kepeng
Powiązania:
https://bibliotekanauki.pl/articles/219132.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
temperatura
beton natryskowy
obszar górniczy
kopalnia
wet shotcrete
frigid area
Fishbone Diagram
temperature
low strength
Opis:
Wet shotcrete technology is being gradually used in roadway support in frigid mining areas. Thus, problems such as low strength, fragility, and high repair rate have also emerged. This study focuses on low strength, cracking, and other problems in the wet shotcrete support of a mine. It introduced the fishbone diagram to investigate the effects of temperature, cement content, and water-cement ratio (W/C) on the strength of the shotcrete layer. The microscopic morphology of wet shotcrete based on scanning electron microscopy (SEM) is observed. Results demonstrated that temperature was the main influencing factor of wet shotcrete in frigid mining areas. When the curing temperature was lower than 10°C, the early strength of wet shotcrete dropped significantly. Temperatures above 15°C were favorable for later gain in strength. W/C was of a complementary relationship with strength development at different ages. Temperature was the essential factor that influenced the microscopic morphology of wet shotcrete. Furthermore, internal initial porosity and aggregate interface bonding strength had a direct effect on macro-mechanical properties of wet shotcrete.
Źródło:
Archives of Mining Sciences; 2020, 65, 2; 285-298
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A decision diagram based reliability evaluation method for multiple phased-mission systems
Metoda oceny niezawodności systemów wielofazowych w oparciu o diagramy decyzyjne
Autorzy:
Zhang, S.
Sun, S.
Si, S.
Wang, P.
Powiązania:
https://bibliotekanauki.pl/articles/301521.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
systemy wielofazowe
binarny diagram decyzyjny
wielostanowy wielowartościowy diagram decyzyjny
ocena niezawodności
multiple phased-mission systems
Binary decision diagram
multi-state multi-valued decision diagram
reliability evaluation
Opis:
The multiple phased-mission system (MPMS) exists widely in practical engineering, such as aviation, spaceflight and navigation fields. Its distinct characteristic is that the system usually performs multiple missions and each mission consists of different phases. In this paper, we mainly focus on the reliability analysis for MPMS when the components have to accomplish different missions successively. A new modeling method is proposed for MPMS analysis based on the binary decision diagram (BDD) and multi-state multi-valued decision diagram (MMDD). Through this method, different phases of missions are combined with in the whole system by certain merging rules according to the operating time of a common component. Then, the system reliability can be calculated by the common calculation methods of decision diagrams by generating the through. Finally, two case studies are implemented to demonstrate the generation of BDD/MMDD models and the evaluation of system reliability. The experiment results verified the efficiency and accuracy of the proposed modeling methods.
Systemy wielofazowe (Multiple Phased-Mission Systems, MPMS), t.j. systemy o wielu zadaniach okresowych są powszechnie stosowane w praktyce inżynieryjnej, np. w lotnictwie, lotach kosmicznych czy nawigacji. Cechą wyróżniającą tego typu systemy jest to, że zazwyczaj wykonują one wiele zadań, z których każde składa się z różnych faz. Głównym tematem poniższej pracy jest analiza niezawodności MPMS dla przypadków, kiedy elementy składowe muszą wykonywać różne misje jedna po drugiej. W artykule zaproponowano nową metodę modelowania dla celów analizy MPMS opartą na koncepcji binarnego diagramu decyzyjnego (binary decision diagram, BDD) oraz wielostanowego wielowartościowego diagramu decyzyjnego (multi-state multi-valued decision diagram, MMDD). Metoda ta polega na łączeniu różnych faz misji w obrębie systemu za pomocą pewnych reguł łączenia wedle czasu pracy wspólnego elementu składowego. Pozwala to na obliczanie niezawodności systemu za pomocą powszechnie stosowanych metod diagramów decyzyjnych poprzez generowanie drzew błędów. W pracy zaprezentowano dwa studia przypadku, które pokazują, w jaki sposób generuje się modele BDD/MMDD oraz ocenia niezawodność systemu. Wyniki eksperymentów wykazały wydajność oraz trafność proponowanych metod modelowania.
Źródło:
Eksploatacja i Niezawodność; 2017, 19, 3; 485-492
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phase Transition and Plasticity Enhancement of Ti-Cu-Based Bulk Metallic Glasses
Autorzy:
Wang, L.
Wang, X.
Zhang, G.
Sun, X.
Powiązania:
https://bibliotekanauki.pl/articles/356824.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
bulk metallic glasses
phase transition
annealing
stability
plasticity
Opis:
In this paper, we report the complex crystallization kinetics of phase transition happening in Ti-Cu-based bulk metallic glasses (BMGs), which play significant roles in the glass formation with respect to their low reduced glass transition temperatures, Trg. The first exothermic event just occurs when annealing the BMG samples in the supercooled liquid region, leading to the Avrami exponent deviating from conventional modes affected by the residual amorphous phase. For Ti43Cu43Ni7Zr7 BMG, the plasticity can be improved by pre-annealing at a sub-Tg temperature of 623K (≈50K below Tg) for 0.5 hour, however, deteriorated by 1 hour annealing, which could be related to the change in stability of this BMG against crystallization with different pre-annealing times.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 1; 387-391
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quaternion-based filtering for gyroless attitude estimation without an attitude dynamics model
Autorzy:
Zhang, S.
Xing, F.
Sun, T.
You, Z.
Powiązania:
https://bibliotekanauki.pl/articles/220655.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
quaternion-based filtering
gyroless attitude estimation
angular velocity determination
Kalman filter
Opis:
Conventionally, the filtering technique for attitude estimation is performed using gyros or attitude dynamics models. In order to extend the application range of an attitude filter, this paper proposes a quaternion-based filtering framework for gyroless attitude estimation without an attitude dynamics model. The attitude estimation system is established based on a quaternion kinematic equation and vector observation models. The angular velocity in the system is determined through observation vectors from attitude sensors and the statistical properties of the angular velocity error are analysed. A Kalman filter is applied to estimate the attitude error such that the effect from the angular velocity error is compensated with its statistical properties at each sampling moment. A numerical simulation example is presented to illustrate the performance of the proposed algorithm.
Źródło:
Metrology and Measurement Systems; 2018, 25, 3; 631-643
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of dynamic characteristics of an experimental bench of high-pressure water fracturing assisted cutting
Autorzy:
Liu, Zhiming
Zhang, Qiang
Sun, Yuliang
Liu, Junming
Powiązania:
https://bibliotekanauki.pl/articles/2200892.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
high-pressure water fracturing
experimental bench
dynamic characteristics
Opis:
Aiming at the problem that the cutting efficiency of a drum shearer is low when mining hard coal seams, an experimental bench of high-pressure water fracturing assisted cutting is designed. Compared with normal ones, the maximum equivalent stress of the improved experimental bench is reduced by 55.38%, and the maximum total deformation is reduced by 27.23%. According to the results of dynamic response analysis, it is concluded that the experimental bench of high-pressure water fracturing assisted cutting is stable and reliable under extreme working conditions, and meets design requirements for strength and stiffness.
Źródło:
Journal of Theoretical and Applied Mechanics; 2023, 61, 2; 317--330
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Polytetrafluorethylene on the Mechanical and Safety Properties of a Composite Modified Double Base Propellant
Autorzy:
Sun, S.
Zhang, T.
Zhao, B.
Zhang, G.
Li, X.
Luo, Y.
Powiązania:
https://bibliotekanauki.pl/articles/358296.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
PTFE fibres
CMDB propellant
mechanical properties
mechanical sensitivity
combustion
Opis:
A novel Composite Modified Double Base (CMDB) propellant, formed by mechanically mixing aluminium/polytetrafluorethylene (Al/PTFE) powders, was prepared through a rolling process. A variety of tests, such as tensile properties, particle size analysis etc., were carried out to study the influence of PTFE on the CMDB propellant properties. The PTFE deformed from particles to fibres under a uniform shear force, forming a fibre network which greatly improved the propellant’s mechanical properties. Compared to that of the CMDB propellant without PTFE, the elongation of the propellant containing 6% PTFE was increased by 26 times, and moreover, the impact strength was enhanced by 326% at −40 °C. Significantly, the propellant friction and impact sensitivities were reduced by 75.8% and 35.6%, respectively. In addition, the presence of PTFE in the propellant resulted in fluorination of the Al. The gaseous combustion product AlF3 reduced the propellant combustion agglomeration. Consequently, PTFE significantly promoted the propellant’s mechanical performance, decreased the shock (friction, impact) sensitivity and reduced combustion agglomeration.
Źródło:
Central European Journal of Energetic Materials; 2018, 15, 3; 468-484
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cassiterite recovery from a sulfide ore flotation tailing by combined gravity and flotation separations
Autorzy:
Zhang, Limin
Khoso, Sultan Ahmed
Tian, Mengjie
Sun, Wei
Powiązania:
https://bibliotekanauki.pl/articles/1448947.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Cassiterite
Falcon concentrator
shaking table
flotation
gravity separation
Opis:
Cassiterite (SnO2) which is the most important Sn-containing mineral, is extensively found in large quantities in discarded tailings. The recovery of cassiterite from discarded sulfide ore flotation tailings can reduce resource wastage and environmental pollution. The gravity separation technique can recover multiple valuable minerals, such as cassiterite, whose densities considerably differ from those of their associated gangue minerals. However, its recovery efficiency rapidly decreases as the mineral particle grain size decreases. To recover the finer valuable mineral particles from gravity separation tailings, flotation separation can be used as a supplementary method. In this study, the gravity and flotation separation techniques are combined to recover cassiterite from a sulfide ore tailing. The Sn grade and recovery of the final concentrate is 31.40% and 88.05%, respectively, thus indicating a highly efficient recovery of cassiterite by using the combined gravity and flotation separation technique. This study can be an important reference for recovering cassiterite from low-Sn-grade tailings.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 1; 206-215
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation, Structure and Kinetic Analysis of the Thermal Behavior of Some Energetic Salts of 3-Hydrazino-4-amino-1,2,4-triazole
Autorzy:
Wu, J. T.
Zhang, J. G.
Sun, M.
Yin, X.
Zhang, T. L.
Powiązania:
https://bibliotekanauki.pl/articles/358073.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
synthesis
crystal structure
thermal analysis
3-hydrazino-4-amino-1,2,4-triazole
energetic salts
Opis:
As a key research objective for low melting explosives and propellants, energetic salts have received worldwide attention. 3-Hydrazino-4-amino-1,2,4triazole (HATr) is an important high-nitrogen compound (73.65% N) with good stability. This paper focuses on the energetic salts which were formed between HATr and picric acid (PA) or 2,4,6-trinitroresorcinol (TNR). Single crystals of HATr·PA and HATr·TNR·H2O were grown and their crystal structures determined at low temperature. They both belong to the monoclinic system, P21/n space group. The thermal characteristics of the two target salts were investigated using DSC and TG-DTG. In addition, the non-isothermal decomposition kinetics, heats of combustion and sensitivity have also been investigated. The detonation pressures (P) and detonation velocities (D) of the salts have been calculated using the K-J equations. The results indicated that both salts have certain potential applications as gunpowder and propellant materials.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 4; 481-493
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
COMBINATION OF BERBERINE AND MATRINE AFFECTS APOPTOSIS AND CELLCYCLE IN HUMAN CERVICAL CANCER CELLS
Autorzy:
Zhang, Qijiayu
Sun, Yi
Huang, Yuxi
Sun, Jing
Zhao, Chongbo
Song, Yijun
Wu, Juanhua
Powiązania:
https://bibliotekanauki.pl/articles/895719.pdf
Data publikacji:
2019-12-29
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
apoptosis
cervical cancer
Matrine
berberine
Opis:
Cervical cancer is the fourth leading cause of malignancy-related mortality in women worldwide, and effective advanced-stage therapies are urgently required. Berberine is a quaternary ammonium compound extracted from traditional Chinese medicinal herbs, including Phellodendron spp., with antibacterial and antitumor activities. Matrine, the main active ingredient of Sophora flavescens rhizomes, has not only traditionally described health effects but is also widely used for its anticancer, anti-inflammatory, immunoregulatory, antiviral, and hepatoprotective effects. We investigated the antitumor activities of berberine and matrine against human cervical cancer HeLa and SiHa cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, along with flow cytometry and western blotting analyses, to assess the effect of the compounds on the cellular status and apoptosis- and cell cycle-related proteins. The 24 h half-maximal inhibitory concentrations (IC50) of berberine and matrine were 123.633 ± 4.278 µmol/L and 9.625 ± 0.245 mmol/L against HeLa cells and 105.067 ± 3.745 µmol/L and 8.50 ± 0.23 mmol/L against SiHa cells, respectively. Berberine plus matrine inhibited cancer cell growth and caused cell cycle arrest. We observed an increased stimulation of apoptosis, which was likely mediated by enhanced levels of caspase-3, caspase-9, and B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax), as well as decreased Bcl-2 protein expression. Cell cycle arrest in the G1 phase was probably mediated by p21 upregulation and cyclin-dependent kinase (Cdk)-4, Cdk-6, and cyclin D1 suppression. Combination treatment with berberine and matrine effectively inhibited human cervical cancer cell proliferation, most likely by stimulating apoptosis and inducing cell cycle arrest.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 6; 1089-1097
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fatigue Behavior and Mechanism of FV520B-I Owing to the Effect of Loading Frequency on the Fatigue Property in HCF and VHCF Regime
Autorzy:
Wang, J.
Zhang, Y.
Shi, B.
Zhao, Q.
Sun, Q.
Zhang, Z.
Lu, H.
Powiązania:
https://bibliotekanauki.pl/articles/353784.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ultrahigh loading frequency
FV520B-I
fatigue strength
fatigue conversion model
Opis:
Fatigue property of FV520B-I is affected by the ultrahigh loading frequency significantly, and the ultrasonic fatigue experimental data can’t be employed directly to analyze the fatigue failure in the actual remanufacturing engineering. However few theories about the effect of loading frequency on the fatigue property of FV520B-I has ever been proposed. In this paper, both ultrasonic experiment and conventional experiment are conducted out to obtain the fatigue data. The effect of loading frequency on the fatigue data distribution is discussed firstly, its fatigue limit declines with the increase of the loading frequency. Then the fracture surface observations are captured, the fatigue property and fatigue behavior mechanism of FV520B-I is examined by analyzing the fracture surface features, crack initiation and failure observations. A new material frequency correction factor is proposed and introduced to eliminate the influence of the loading frequency on the FV520B-I fatigue property. FV520B-I empirical fatigue life conversion model and fatigue strength conversion model are established with comprehensive use of a fitting algorithm based on the combination of experimental data and classic formula. A clear understand of the effect of loading frequency on the fatigue property of FV520B-I is novel and has an important significance in guaranteeing the accuracy of the actual fatigue analysis of FV520B-I in the remanufacturing engineering.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 1; 347-357
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative Study of the Penetration Characteristics of Ni-Al and Pure Cu Shaped Charge Liners
Autorzy:
Liu, Yingbin
Zhang, Chaoxia
Hu, Xiaoyan
Yang, Li
Sun, Miao
Zhang, Zeng
Yuan, Lei
Powiązania:
https://bibliotekanauki.pl/articles/27788048.pdf
Data publikacji:
2021
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
shaped charge liners
Ni-Al
penetration experiments
white band
microstructure analysis
Opis:
In order to investigate the correlation between the reactivity of Ni-Al and micro-structural differences in the crater walls, penetration experiments were performed with Ni-Al and pure Cu shaped charge liners (SCLs). The experimental results showed that the average penetration depth of Cu jets is 2.3 times that of Ni-Al jets, but the crater entrance diameter of Ni-Al jets is larger by 26.6%. The microstructure of the recovered targets was characterized using optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, and a Vickers micro-hardness system. The Ni-Al “white” band was thicker than that of Cu because it releases a lot of heat. The micro-hardness test showed that the “white” band had a relatively high hardness, and the “white” band hardness in the tail was more significant than that in the head. However, the micro-structural evolution of the crater walls is related to the reactivity of Ni-Al, but is also related to other factors. Combined with the macro penetration results and the evolution of the micro-structure of the crater walls, the “white” band can absorb impact energy more strongly and weaken the jet breaking ability or armour protection ability.These results can provide more valuable reference for designing shaped charge warheads and protection structures.
Źródło:
Central European Journal of Energetic Materials; 2021, 18, 2; 199--222
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Network resource reallocation strategy based on an improved capacity-load model
Strategia realokacji zasobów sieciowych oparta o udoskonalony model przepustowości-obciążenia
Autorzy:
Zhou, J.
Huang, N.
Sun, X.
Xing, L.
Zhang, S.
Powiązania:
https://bibliotekanauki.pl/articles/300643.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
network reliability
maintenance
resource reallocation
cascading failures
capacity-load relationship
niezawodność sieci
utrzymanie ruchu
realokacja zasobów
awarie kaskadowe
zależność przepustowość
obciążenie
Opis:
Network resource reallocation is a common way to help restore performance of network systems subject to cascading failures. Majority of current network resource allocation strategies either give little regard to or make impractical assumptions about the relationship between capacity and load of network nodes, despite this relationship is closely related to the propagation of network failures. In this work we present and verify an improved nonlinear network capacity-load model based on the actual relation between network capacity and load. According to the verified model and realistic dynamic characteristics of network loads, we propose a new network resource reallocation strategy for networks under attacks from the perspective of maintenance. The strategy aims to effectively reallocate new capacity to network nodes after cascading failures occur. Both theoretical analysis and empirical studies are performed on three typical types of complex networks. Results show that the proposed network resource reallocation strategy is more efficient in mitigating devastating impact of cascading failures on network performance, in comparison to other three existing network resource reallocation strategies.
Realokacja zasobów sieci jest powszechnym sposobem, stosowanym w celu przywrócenia działania systemów sieciowych objętych awariami kaskadowymi. Większość współczesnych strategii alokacji zasobów sieciowych kładzie mały nacisk lub czyni niepraktyczne założenia dotyczące zależności między przepustowością i obciążeniem węzłów sieci, choć zależność ta jest ściśle związana z rozchodzeniem się awarii sieci. W niniejszej pracy przedstawiono i zweryfikowano udoskonalony nieliniowy model przepustowości-obciążenia sieci na podstawie rzeczywistej relacji między przepustowością sieci i jej obciążeniem. Na podstawie zweryfikowanych modelu i realistycznych cech dynamicznych obciążeń sieciowych, proponujemy nową strategię realokacji zasobów dla sieci poddawanych atakom z perspektywy utrzymania ruchu. Celem strategii jest skuteczna realokacja nowej przepustowości węzłom sieci po wystąpieniu kaskadowych awarii. Przeprowadzono zarówno teoretyczne analizy, jak i badania empiryczne na trzech typowych rodzajach sieci złożonych. Wyniki pokazują, że proponowana strategia realokacji zasobów sieci jest bardziej skuteczna w zwalczaniu niszczącego wpływu kaskadowych awarii na przepustowość sieci w porównaniu do pozostałych trzech wykorzystywanych strategii realokacji zasobów sieciowych.
Źródło:
Eksploatacja i Niezawodność; 2015, 17, 4; 487-495
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reliability analysis for multi-state system based on triangular fuzzy variety subset bayesian networks
Analiza niezawodności systemu wielostanowego z zastosowaniem sieci bayesowskich opartych na rozmytych podzbiorach zmienności opisanych przez trójkątną funkcję przynależności
Autorzy:
He, Q.
Zha, Y.
Zhang, R.
Sun, Q.
Liu, T.
Powiązania:
https://bibliotekanauki.pl/articles/302183.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
teoria zbiorów rozmytych
system wielostanowy
sieć bayesowska
wypadek podczas ruchu wózka windy
analiza niezawodności
reliability analysis
fuzzy set theory
Multi-State System
Bayesian network
elevator free movement accident
Opis:
W niniejszej pracy zaproponowano nową metodę analizy niezawodności systemów wielostanowych wykorzystującą sieci Bayesa (BN) oparte na rozmytych podzbiorach zmienności opisanych za pomocą trójkątnej funkcji przynależności. Metoda ta uwzględnia rozmyty charakter danych dotyczących uszkodzeń, wielostanowość systemu oraz zmienność prawdopodobieństwa wystąpienia uszkodzenia w czasie. BN, które znalazły zastosowanie w modelowaniu i metodach obliczeniowych, wykorzystuje się także do analizy niezawodności. W przedstawionych badaniach, analizę BN uzupełniono o elementy teorii zbiorów rozmytych wykorzystując do opisu prawdopodobieństwa wystąpienia uszkodzenia, podzbiory zmienności opisane przez trójkątną funkcję przynależności. Niepewność zależności logicznej pomiędzy awariami reprezentowanymi przez różne węzły sieci opisano za pomocą tabel rozmytego prawdopodobieństwa warunkowego. W pierwszej kolejności analizowano prawdopodobieństwo uszkodzenia każdego korzenia (węzła głównego) w funkcji czasu. Następnie, wyznaczono trójkątny rozmyty podzbiór zmienności, za pomocą którego opisano rozmyte prawdopodobieństwo uszkodzenia węzłów głównych. Podzbiór ten wykorzystano do analizy niezawodności systemu wielostanowego przy pomocy rozmytych BN. Artykuł kończy opis wypadku podczas ruchu wózka windy szybkobieżnej, który potwierdza skuteczność i możliwość praktycznego wykorzystania proponowanej metody. Wyniki pokazują, że proponowane podejście może skutecznie rozwiązywać na wczesnym etapie problemy związane z niepewnością informacji oraz wielostanowością systemu.
In this paper, a novel reliability analysis method for multi-state system is proposed on the basis of triangular fuzzy variety subset Bayesian network (BN). The method considers fuzziness, multi-state, and variety of failure probability over time. With advantages in modeling and computation, the BN is utilized for reliability analysis. Fuzzy set theory is introduced into the BN analysis by using triangular fuzzy variety subset to describe failure probability. The uncertainty of fault logical relationship between different nodes is described through fuzzy conditional probability tables. As a function of time, the failure probability of each root node is analyzed first. Subsequently, the triangle fuzzy variety subset is established to describe the fuzzy failure probability of root nodes. This subset is applied to analyze the reliability of multi-state system fuzzy BN. Finally, a case study on the car free movement accident of flexible high-speed elevator lift system is used to demonstrate the effectiveness and practicality of the proposed method. Results show that the proposed approach could effectively address the problems on information uncertainty and multi-state in the early stage.
Źródło:
Eksploatacja i Niezawodność; 2017, 19, 2; 158-165
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fatigue alters the biomechanical contribution of lower extremity joints during a stretch-shortening cycle task
Autorzy:
Sun, Xiaole
Xia, Rui
Zhang, Ximi
Zhen, Luo
Fu, Weijie
Powiązania:
https://bibliotekanauki.pl/articles/949743.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
skoki
zmęczenie
sztywność
stretch-shortening cycle
drop jump
fatigue
stiffness
joint work
Opis:
This study aimed to explore the effect of fatigue on the biomechanical contribution of the lower extremity joints during a typical stretch-shortening cycle (SSC) task. Methods: 15 male athletes completed drop jump (DJ) under pre- and post-fatigue. Vicon motion capture system and 3D Kistler force plates were used to collect kinematics and ground reaction force data simultaneously. Results: Under fatigue condition, 1) the DJ height decreased; the touchdown angle of knee and ankle reduced and the range of motion increased; 2) the maximum push-off moment and power of knee was reduced; 3) the stiffness of knee, ankle, and legs was reduced; 4) the energy generation and the net energy of the ankle decreased; 5) the energy contribution of knee decreased during the eccentric phase. Conclusions: Fatigue altered biomechanical contribution of the lower extremity joints by changing the movement pattern during DJ. The control ability of the knee and ankle were decreased. Eventually, the jump performance was reduced. In addition, the decrease of stiffness as well as the energy contribution of these joints can be used as sensitive indices to evaluate the performance of DJ after fatigue.
Źródło:
Acta of Bioengineering and Biomechanics; 2019, 21, 2; 11-19
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
HPM Generation by Tri-Anode Coaxial Vircator
Autorzy:
Shao, H.
Liu, G.
Zhang, Y.
Yang, Z.
Sun, J.
Powiązania:
https://bibliotekanauki.pl/articles/1807906.pdf
Data publikacji:
2009-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.47.Gk
Opis:
A novel type of coaxial vircator with 3 anodes is proposed. The advantages on high power microwave generation is tested by particle-in-cell simulation and theoretical analysis model is set up as well. The tri-anode coaxial vircator behaves a very stable frequency in the pulse duration. In the tri-anode coaxial vircator, the injecting electron beam is well premodulated in the first anode cavity and forms an inerratic bunch-dispersion mechanism in the second anode cavity; the energy-loss electrons penetrate through the third anode and absorbed by the dumping cavity locates in the centre electrode, which helps keeping the bunch-dispersion cycle undisturbed. A 3.8 GHz tri-anode coaxial vircator is theoretically designed and optimized by particle-in-cell simulation, which gives beam-wave conversion efficiency of over 20% with a stable predominant frequency, in accordance with the particle-in-cell simulation and analytic model.
Źródło:
Acta Physica Polonica A; 2009, 115, 6; 1047-1049
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Compressive deformation characteristics of crushed sandstone based on multiple experimental factors
Autorzy:
Sun, Yanan
Zhang, Peisen
Yan, Wei
Yan, Fenqian
Wu, Junda
Powiązania:
https://bibliotekanauki.pl/articles/219794.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mechanika skał
skały kruche
odkształcenie
rock mechanics
saturated graded crushed rock
compressive deformation
cyclic loading
cyclic unloading
Opis:
In this study, the compressive deformation of crushed sandstone was tested using a crushed rock deformation-seepage test system, and the effects of various factors, including crushed rock grade, grade combination, water saturation status, and stress loading method (i.e., continuous loading or cyclic loading and unloading), on the compressive deformation of crushed sandstone was analyzed from four perspectives including stress-strain, bulking coefficient, deformation mechanism and energy dissipation. The results indicate that the stress-strain relations of crushed sandstone are closely associated with all factors considered, and are well represented by exponential functions. The strain observed for a given applied stress increased with increasing crushed rock grade throughout the loading period. Crushed sandstone grades were combined according to a grading index (n), where the proportion of large-grade rocks in the sample increased with increasing n. The bearing capacity of a water-saturated crushed sandstone sample with n = 0.2 was less than that of an equivalent dry sample for a given applied stress. The stress-strain curve of a water-saturated crushed sandstone sample with n = 0.2 under cyclic loading and unloading was similar to that obtained under continuous loading. Observation and discovery, the deformation mechanism of crushed sandstone was mainly divided into four stages, including crushing, rupture, corner detachment and corner wear. And 20% of the work done by testing machine is used for friction between the crushed sandstone with the inner wall of the test chamber, and 80% is used for the closing of the void between the crushed sandstone, friction sliding, crushing damage.
Źródło:
Archives of Mining Sciences; 2020, 65, 1; 129-146
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High drilling methane drainage in fracturing zones formed by water injection into boreholes
Odprowadzania metanu metodą odwiertów dokonywanych w strefie szczelin powstałych wskutek wprowadzania wody do otworów
Autorzy:
Wang, G.
Huang, W.
Sun, L.
Wu, M.
Zhang, X.
Powiązania:
https://bibliotekanauki.pl/articles/220166.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
odwierty
odprowadzenie metanu
wtrysk wody
szczelinowanie
odkształcenia
high drilling
methane drainage
water injection
fracturing zones
strain
Opis:
Methane drainage method should be used before coal mining of many modern collieries because venti lation air methane is in sufficient to keep methane level within regulation values. The technology of high drilling methane drainage (HDMD) has been used for methane drainage although its effect is not very stable due to parameter design. The height of the fracturing zones is determined mostly according to empirical formula, on-site observation and numerical simulation analysis. In this paper, a method was introduced for determining the height of the air f ract uring zones (AFZs) based on its high similarity to the characteristics of Fracturing zones and the relationship between the height of Fracturing zones and the strain of overl ying rock strata. The application of water injection in both Shuangdingshan and Dongrong collieries found that the theoretically calculated the height of the Fracturing zones was approximately equal to the measured one in field tests within a permissible error of less than 5%, proving that the method is feasible. Based on the designed drainage parameters, the u tilization of HDMD technology in the collieries mentioned above found that the methane concentrations in both tail gate and upper corner were controlled in the ranges of 0.17% to 0.32% and 0.26% to 0.84%, respectively. These results showed that the water injection verified HDMD in Fracturing zones could effectively solve the problem of metha ne overrun and also verified the accuracy and reliability of its related theory.
Przed rozpoczęciem wydobycia węgla w wielu obecnie eksploatowanych kopalniach wskazane jest odprowadzenie metanu, ponieważ stosowane systemy wentylacji powietrza są niewystarczające aby utrzymać stężenia metanu na dopuszczalnym poziomie. Technologia odprowadzania metanu metodą odwiertów prowadzonych na różnej wysokości (HDMD) wykorzystywana jest w tym celu, choć jej wyniki nie zawsze są stabilne ze względu na konieczność doboru parametrów obliczeniowych. Wysokość strefy szczelinowania określa się zazwyczaj empirycznie, na podstawie obserwacji w terenie oraz drogą symulacji numerycznych. W pracy tej określono wysokość strefy wykonania szczelin w oparciu o podobieństwo do charakterystyk Strefy szczelinowania oraz o analizę odkształceń warstw nadkładu. Zastosowano wtrysk wody w kopalniach Shuangdingshan i Dongrong i stwierdzono, że teoretycznie obliczona wysokość stref szczelinowania była w przybliżeniu równa wysokości zmierzonej empirycznie w trakcie badań terenowych, z dopuszczalnym poziomem błędu poniżej 5%, co wskazuje na możliwość zastosowania metody. W oparciu o parametry obliczeniowe stwierdzono, że zastosowanie metody HDMD w wyżej wymienionych kopalniach spowodowało, że stężenia metanu rejestrowane w chodniku nadścianowym i górnych narożach utrzymywały się odpowiednio na poziomie 0.17%, 0.32% i 0.26%-0.84%. Wyniki te pokazują, że wtrysk wody w strefie szczelin pomaga skutecznie rozwiązać problem obecności zbyt wysokich ilości metanu, ponadto potwierdza dokładność i wiarygodność teorii na której metoda jest oparta.
Źródło:
Archives of Mining Sciences; 2016, 61, 1; 137-156
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
De novo sequencing and comparative transcriptome analysis of white petals and red labella in Phalaenopsis for discovery of genes related to flower color and floral differentiation
Autorzy:
Yang, Y.
Wang, J.
Ma, Z.
Sun, G.
Zhang, C.
Powiązania:
https://bibliotekanauki.pl/articles/58306.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
sequencing
RNA sequence
transcriptome
Phalaenopsis
gene
flower
colour
floral differentiation
diversity
Opis:
Phalaenopsis is one of the world’s most popular and important epiphytic monopodial orchids. The extraordinary floral diversity of Phalaenopsis is a reflection of its evolutionary success. As a consequence of this diversity, and of the complexity of flower color development in Phalaenopsis, this species is a valuable research material for developmental biology studies. Nevertheless, research on the molecular mechanisms underlying flower color and floral organ formation in Phalaenopsis is still in the early phases. In this study, we generated large amounts of data from Phalaenopsis flowers by combining Illumina sequencing with differentially expressed gene (DEG) analysis. We obtained 37 723 and 34 020 unigenes from petals and labella, respectively. A total of 2736 DEGs were identified, and the functions of many DEGs were annotated by BLAST-searching against several public databases. We mapped 837 up-regulated DEGs (432 from petals and 405 from labella) to 102 Kyoto Encyclopedia of Genes and Genomes pathways. Almost all pathways were represented in both petals (102 pathways) and labella (99 pathways). DEGs involved in energy metabolism were significantly differentially distributed between labella and petals, and various DEGs related to flower color and floral differentiation were found in the two organs. Interestingly, we also identified genes encoding several key enzymes involved in carotenoid synthesis. These genes were differentially expressed between petals and labella, suggesting that carotenoids may influence Phalaenopsis flower color. We thus conclude that a combination of anthocyanins and/or carotenoids determine flower color formation in Phalaenopsis. These results broaden our understanding of the mechanisms controlling flower color and floral organ differentiation in Phalaenopsis and other orchids.
Źródło:
Acta Societatis Botanicorum Poloniae; 2014, 83, 3
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on hybrid modeling and predictive energy management for power split hybrid electric vehicle
Autorzy:
Wang, Shaohua
Zhang, Sheng
Shi, Dehua
Sun, Xiaoqiang
Yang, Tao
Powiązania:
https://bibliotekanauki.pl/articles/2173576.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
power split HEV
energy management
mixed logical dynamical model
piecewise affine
model predictive control
podział mocy
zarządzanie energią
silnik hybrydowy
model dynamiczny
model mieszany
model logiczny
technologia fragmentarycznie pokrewna
kontrola predykcyjna modelu
Opis:
Due to the coexistence of continuity and discreteness, energy management of a multi-mode power split hybrid electric vehicle (HEV) can be considered a typical hybrid system. Therefore, the hybrid system theory is applied to investigate the optimum energy distribution strategy of a power split multi-mode HEV. In order to obtain a unified description of the continuous/discrete dynamics, including both the steady power distribution process and mode switching behaviors, mixed logical dynamical (MLD) modeling is adopted to build the control-oriented model. Moreover, linear piecewise affine (PWA) technology is applied to deal with nonlinear characteristics in MLD modeling. The MLD model is finally obtained through a high level modeling language, i.e. HYSDEL. Based on the MLD model, hybrid model predictive control (HMPC) strategy is proposed, where a mixed integer quadratic programming (MIQP) problem is constructed for optimum power distribution. Simulation studies under different driving cycles demonstrate that the proposed control strategy can have a superior control effect as compared with the rule-based control strategy.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 3; art. no. e137064
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design and evaluation of a needle tip measurement system based on binocular vision
Autorzy:
Lin, Yuyang
Shi, Yunlai
Zhang, Jun
Wang, Fugang
Sun, Haichao
Powiązania:
https://bibliotekanauki.pl/articles/220501.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
needle tip measurement
binocular vision system
measurement capability analysis
non-contact optical positioning
Opis:
The precise location of the needle tip is critical in robot-assisted needle-based percutaneous interventions. An automatic needle tip measuring system based on binocular vision technology with the advantages of non-contact, excellent accuracy and high stability is designed and evaluated. First the measurement requirements of the prostate intervention robot are introduced. A laser interferometer is used as the reference for measuring the position of the needle tip whose relative position variation is described as the needle tip distance in the time domain. The parameters of the binocular cameras are obtained by Zhang’s calibration method. Then a robust needle tip extraction algorithm is specially designed to detect the pixel coordinates of the needle tip without installing the marked points. Once the binocular cameras have completed the stereo matching, the 3D coordinates of the needle tip are estimated. The measurement capability analysis (MCA) is used to evaluate the performance of the proposed system. The accuracy of the system can be controlled within 0.3621 mm. The agreement analysis is conducted by the Bland-Altman analysis, and the Pearson correlation coefficient is 0.999847. The P/T ratio value is 16.42% in the repeatability analysis. The results indicate that the accuracy and stability of the binocular vision needle tip measuring system are adequate to meet the requirement for the needle tip measurement in percutaneous interventions.
Źródło:
Metrology and Measurement Systems; 2020, 27, 3; 495-512
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Driving energy management of front-and-rear-motor-drive electric vehicle based on hybrid radial basis function
Autorzy:
Sun, Binbin
Zhang, Tiezhu
Ge, Wenqing
Tan, Cao
Gao, Song
Powiązania:
https://bibliotekanauki.pl/articles/224152.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electric vehicle
drive
energy management
optimization
torque distribution
predictive model
hardware test
pojazd elektryczny
napęd
zarządzanie energią
optymalizacja
moment obrotowy
model predykcyjny
Opis:
This paper presents mathematical methods to develop a high-efficiency and real-time driving energy management for a front-and-rear-motor-drive electric vehicle (FRMDEV), which is equipped with an induction motor (IM) and a permanent magnet synchronous motor (PMSM). First of all, in order to develop motor-loss models for energy optimization, database of with three factors, which are speed, torque and temperature, was created to characterize motor operation based on HALTON sequence method. The response surface model of motor loss, as the function of the motor-operation database, was developed with the use of Gauss radial basis function (RBF). The accuracy of the motor-loss model was verified according to statistical analysis. Then, in order to create a two-factor energy management strategy, the modification models of the torque required by driver (Td) and the torque distribution coefficient (β) were constructed based on the state of charge (SOC) of battery and the motor temperature, respectively. According to the motor-loss models, the fitness function for optimization was designed, where the influence of the non-work on system consumption was analyzed and calculated. The optimal β was confirmed with the use of the off-line particle swarm optimization (PSO). Moreover, to achieve both high accuracy and real-time performance under random vehicle operation, the predictive model of the optimal β was developed based on the hybrid RBF. The modeling and predictive accuracies of the predictive model were analyzed and verified. Finally, a hardware-in-loop (HIL) test platform was developed and the predictive model was tested. Test results show that, the developed predictive model of β based on hybrid RBF can achieve both real-time and economic performances, which is applicable to engineering application. More importantly, in comparison with the original torque distribution based on rule algorithm, the torque distribution based on hybrid RBF is able to reduce driving energy consumption by 9.51% under urban cycle.
Źródło:
Archives of Transport; 2019, 49, 1; 47-58
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on hybrid modeling and predictive energy management for power split hybrid electric vehicle
Autorzy:
Wang, Shaohua
Zhang, Sheng
Shi, Dehua
Sun, Xiaoqiang
Yang, Tao
Powiązania:
https://bibliotekanauki.pl/articles/2128153.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
power split HEV
energy management
mixed logical dynamical model
piecewise affine
model predictive control
podział mocy
zarządzanie energią
silnik hybrydowy
model dynamiczny
model mieszany
model logiczny
technologia fragmentarycznie pokrewna
kontrola predykcyjna modelu
Opis:
Due to the coexistence of continuity and discreteness, energy management of a multi-mode power split hybrid electric vehicle (HEV) can be considered a typical hybrid system. Therefore, the hybrid system theory is applied to investigate the optimum energy distribution strategy of a power split multi-mode HEV. In order to obtain a unified description of the continuous/discrete dynamics, including both the steady power distribution process and mode switching behaviors, mixed logical dynamical (MLD) modeling is adopted to build the control-oriented model. Moreover, linear piecewise affine (PWA) technology is applied to deal with nonlinear characteristics in MLD modeling. The MLD model is finally obtained through a high level modeling language, i.e. HYSDEL. Based on the MLD model, hybrid model predictive control (HMPC) strategy is proposed, where a mixed integer quadratic programming (MIQP) problem is constructed for optimum power distribution. Simulation studies under different driving cycles demonstrate that the proposed control strategy can have a superior control effect as compared with the rule-based control strategy.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 3; e137064, 1--15
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Homogenization phenomena of surface components of fluorite and calcite
Autorzy:
Sun, Ruofan
Liu, Dan
Zhang, Benyue
Lai, Hao
Wen, Shuming
Powiązania:
https://bibliotekanauki.pl/articles/1448969.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
homogenization phenomena
surface composition
fluorite
calcite
mixed grinding
Opis:
The flotation separation of fluorite and calcite poses one of the most difficult problems in the mineral processing industry. In particular, the surface homogenization of fluorite and calcite worsens the result of fluorite flotation. In this paper, time of flight secondary ion mass spectrometry and principal component analysis are used to study the surface homogenization of fluorite and calcite during grinding and in solution using X-ray photoelectron spectroscopy, infrared spectroscopy, and solution chemical calculations. The results show that the surface composition of calcite converts to fluorite after mixed grinding and that the surface composition of fluorite also converts to calcite in clarified calcite solution.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 1; 250-258
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Current status of phenolic pollution in urban lakes and its toxicity to cells : a case study of Xi’an, China
Autorzy:
Wang, Min
Zhang, Yutong
Sun, Jingxin
Huang, Chen
Zhai, Hongqin
Powiązania:
https://bibliotekanauki.pl/articles/27311546.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Urban lakes
phenolic compounds
pollution
ecological risk assessment
miejskie zbiorniki wodne
związki fenolowe
zanieczyszczenie
szacowanie ryzyka
środowisko
Opis:
Liquid chromatography-mass spectrometry was used to detect and analyze phenolic compounds in the surface waters of four urban lakes in Xi’an – Hancheng Lake, Xingqing Lake, Nanhu Lake, and Taohuatan Lake. A total of 5 phenolic compounds were detected from the water samples, with a concentration range of ND-100.32 ng/L, of which bisphenol A (BPA) and nonyl phenol (NP) were the main types of phenolic compounds pollution in the four lakes. Pearson correlation analysis was used to analyze the concentration of phenolic compounds in the lake waters of Xi’an City and the water quality indicators COD, TP, NH3 -N, DO, and pH during the same period. It was found that there was a significant positive relationship between the concentration of BPA and COD, the concentration of estradiol (17-beta-E2), estrone (E1) and TP and TN, the concentration of octylphenol (4-t-OP) and pH. The ecological risk assessment (ERA) shows that the concentration of BPA, 4-t-OP and NP in the lakes is at a medium risk level( is between 0.1–1), and that of E1 is at a high risk level (is greater than 1). Female cells (breast cancer cells) and male germ cells (testis cells) of mice were used as research objects to explore BPA and NP Toxic effect on mouse germ cells. BPA and NP at a concentration of 10-8 mol/L were found to have the most value-inducing effect on MCF-7 breast cancer cells positive for estrogen receptor. Obviously, both BPA and NP can induce the proliferation of testicular Sertoli cells.
Źródło:
Archives of Environmental Protection; 2023, 49, 1; 63--73
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł

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