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Tytuł:
Variable structure observer design for a class of uncertain systems with a time-varying delay
Autorzy:
Liu W., J.
Powiązania:
https://bibliotekanauki.pl/articles/330119.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
obserwator
niezmienniczość
uogólniona odwrotność macierzy
variable structure observer
invariance property
generalized matrix inverse approach
Opis:
Design of a state observer is an important issue in control systems and signal processing. It is well known that it is difficult to obtain the desired properties of state feedback control if some or all of the system states cannot be directly measured. Moreover, the existence of a lumped perturbation and/or a time delay usually reduces the system performance or even produces an instability in the closed-loop system. Therefore, in this paper, a new Variable Structure Observer (VSO) is proposed for a class of uncertain systems subjected to a time varying delay and a lumped perturbation. Based on the strictly positive real concept, the stability of the equivalent error system is verified. Based on the generalized matrix inverse approach, the global reaching condition of the sliding mode of the error system is guaranteed. Also, the proposed variable structure observer will be shown to possess the invariance property in relation to the lumped perturbation, as the traditional variable structure controller does. Furthermore, two illustrative examples with a series of computer simulation studies are given to demonstrate the effectiveness of the proposed design method.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2012, 22, 3; 575-583
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Building the B2B customer loyalty : a role of relationship quality
Budowanie lojalności klienta B2B : rola jakości relacji
Autorzy:
Liu, L.-W.
Yang, W.-G.
Liu, W.-H.
Powiązania:
https://bibliotekanauki.pl/articles/405772.pdf
Data publikacji:
2017
Wydawca:
Politechnika Częstochowska
Tematy:
information sharing
customer orientation
B2B relationship
PLS-SEM
relationship marketing
wymiana informacji
orientacja na klienta
relacje B2B
marketing relacji
Opis:
The purpose of this study was to investigate the E-Commerce relationship quality and loyalty in B2B supplier and client’s relationships. This study tries to conceptualize a model based on the relationship quality that is applied to understand loyalty in B2B environment. The subjects of this study, from whom 81 valid questionnaires were collected, were the clients of the supplier’s ERP system in the Taiwan. When descriptive statistics and partial least squares (PLS) were adopted to analyse the collected valid data, we obtained the following findings. Relationship quality was perceived through the behavior of both supplier and clients and the quality of their interaction. Relationship quality antecedents include the information sharing and customer orientation. The finding suggests that supplier with strong levels of customer orientation, the supplier and clients were built a stronger relationship and high loyalty. Surprisingly, information sharing shown no significant effects on the relationship quality. This study implies that using information sharing and customer orientation strengthen their relationship quality, thereby enhancing loyalty. The finding of this study implies that it is important for a B2B supplier management to understand clients’ needs and responses. B2B suppliers can learn from this study, that customer orientation, relationship quality, commitment, have a positive impact on loyalty in both direct and indirect ways.
Celem artykułu była analiza jakości relacji z klientami i lojalności w handlu elektronicznym u dostawcy B2B. Niniejsze badanie jest próbą konceptualizacji modelu opartego na jakości relacji, który jest próbą zrozumienia lojalności w środowisku B2B. Przedmiotem badania byli wybrani klienci systemu ERP w oparciu na zebranych 81 kwestionariuszach firm na Tajwanie. Przyjęto statystyki opisowe i w oparciu o metodę najmniejszych kwadratów (PLS) w celu przeanalizowania zebranych istotnych danych. Jakość relacji postrzegano poprzez zachowanie zarówno dostawcy, jak i klientów oraz jakość ich interakcji. Jakość relacji przede wszystkim obejmuje dzielenie się informacjami i orientację na klienta. Wyniki sugerują, że dostawcy z silnym poziomem orientacji na klienta, zbudowali silniejszą więź i wysoką lojalność relacji z dostawcami i klientami. Co zaskakujące, wymiana informacji nie wykazała znaczącego wpływu na jakość relacji. Badanie zakłada, że korzystanie z wymiany informacji i orientacja na klienta wzmacnia ich jakość relacji, zwiększając przez to lojalność. Odkrycie tego badania implikuje, że dla dostawcy usług B2B ważne jest zrozumienie potrzeb i odpowiedzi klientów. Dostawcy B2B winni zauważyć, że orientacja na klienta, jakość relacji, zaangażowanie, mają pozytywny wpływ na lojalność zarówno w sposób bezpośredni, jak i pośredni.
Źródło:
Polish Journal of Management Studies; 2017, 16, 1; 105-114
2081-7452
Pojawia się w:
Polish Journal of Management Studies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Robotic rehabilitation of stroke patients using an expert system
Autorzy:
Natarajan, P.
Agah, A.
Liu, W.
Powiązania:
https://bibliotekanauki.pl/articles/384968.pdf
Data publikacji:
2011
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
rehabilitation robots
intelligent systems
human-robot interaction
expert systems
stroke therapy
Opis:
Approximately 50 to 60 percent of the more than five million stroke survivors are moderately or minimally impaired, and may greatly benefit from rehabilitation. There is a strong need for cost-effective, long-term rehabilitation solutions, which require the therapists to provide repetitive movements to the affected limb. This is a suitable task for specialized robotic devices; however, with the few commercially available robots, the therapists are required to spend a considerable amount of time programming the robot, monitoring the patients, analyzing the data from the robot, and assessing the progress of the patients. This paper focuses on the design, development, and clinically testing an expert systembased post-stroke robotic rehabilitation system for hemiparetic arm. The results suggest that it is not necessary for a therapist to continuously monitor a stroke patient during robotic training. Given the proper intelligent tools for a rehabilitation robot, cost-effective long-term therapy can be delivered with minimal supervision.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2011, 5, 1; 47-57
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Szybki wzrost kryształów jako metoda postępowania z odpadowym Mg(OH)2
Rapid growth approaches from nano-Mg(OH)2 to bulk materials and their application in the environment
Autorzy:
Liu, W.
Huang, F.
Lin, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1218409.pdf
Data publikacji:
2012
Wydawca:
Stowarzyszenie Inżynierów i Techników Przemysłu Chemicznego. Zakład Wydawniczy CHEMPRESS-SITPChem
Tematy:
metale ciężkie
nanosorbenty
regeneracja
zatężanie
ścieki rozcieńczone
heavy metal
nono-adsorbents
regeneration
preconcentrate
dilute wastewater
Opis:
Istnieje duże zapotrzebowanie na badania nad detoksykacją nanoodpadów i recyklingiem zużytych nanosorbentów. W niniejszym artykule dokonano przeglądu badań prowadzonych w tej dziedzinie przez naszą grupę. Przetwarzanie nano-Mg(OH)2 z ładunkiem Cr(VI) stanowi nową strategię zagospodarowania nanoodpadów. Nanoodpady zostały przetworzone w nietoksyczny materiał masowy i stężony roztwór zawierający Cr(VI) na drodze szybkiego wzrostu nanokryształów, który spowodował desorpcję i całkowite oddzielenie Cr(VI) od substancji stałej. Stężony roztwór Cr(VI) można poddać recyklingowi przemysłowemu, a oczyszczony produkt stały można stosować w produkcji materiałów ceramicznych, powłok do metali i ognioodpornych tworzyw sztucznych. Przedstawiono też strategię recyklingu nanosorbentu Mg(OH)2 do stosowania go do usuwania Cr(VI) z roztworów o małym stężeniu Cr(VI).
There is a strong demand for the investigations on the detoxification of the nano-wastes or recycling of the loaded nanoadsorbents. This article reviews the studies of our group in this field. The treatment of Cr(VI) loaded nano-Mg(OH)2 introduces a new strategy for nano-waste disposal. The nano-wastes were converted into a nontoxic bulk material and a concentrated solution containing Cr(VI) by the rapid growth of nano-cystals which leads to the desorption and complete separation of Cr(VI) from the solid. The concentrated Cr(VI) solution can be recycled in the industry and the detoxified solid product can be reutilized in ceramics, metal coatings or flame-retardant plastics. Finally, a recycling strategy of Mg(OH)2 nano-adsorbent was provided for the enrichment of Cr(VI) from aqueous solutions of low-concentration Cr(VI).
Źródło:
Chemik; 2012, 66, 9; 919-928
0009-2886
Pojawia się w:
Chemik
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stope stability assessment and effect of horizontal to vertical stress ratio on the yielding and relaxation zones around underground open stopes using empirical and finite element methods
Ocena stabilności przodka wybierkowego i wpływ relacji naprężeń poziomych do pionowych na strefy osiadania i odprężenia w okolicy przodka prowadzonego bez obudowy w kopalniach podziemnych przy zastosowaniu metody empirycznej oraz metody elementów skończonych
Autorzy:
Sepehri, M.
Apel, D.
Liu, W.
Powiązania:
https://bibliotekanauki.pl/articles/219566.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
stability graph
open stope design
numerical modeling
rock mechanics
relaxation zone
underground mining
wykres stabilności
projektowanie przodka wybierkowego
modelowanie numeryczne
mechanika skał
strefa odprężona
górnictwo podziemne
Opis:
Predicting the stability of open stopes can be a challenging task for underground mine engineers. For decades, the stability graph method has been used as the first step of open stope design around the world. However, there are some shortcomings with this method. For instance, the stability graph method does not account for the relaxation zones around the stopes. Another limitation of the stability graph is that this method cannot to be used to evaluate the stability of the stopes with high walls made of backfill materials. However, there are several analytical and numerical methods that can be used to overcome these limitations. In this study, both empirical and numerical methods have been used to assess the stability of an open stope located between mine levels N9225 and N9250 at Diavik diamond underground mine. It was shown that the numerical methods can be used as complementary methods along with other analytical and empirical methods to assess the stability of open stopes. A three dimensional elastoplastic finite element model was constructed using Abaqus software. In this paper a sensitivity analysis was performed to investigate the impact of the stress ratio “k” on the extent of the yielding and relaxation zones around the hangingwall and footwall of the understudy stope.
Prognozowanie stabilności przodka wybierkowego stanowi poważne wyzwanie dla inżynierów górnictwa. Przez dziesięciolecia na całym świecie do projektowania przodka wybierkowego prowadzonego bez obudowy wykorzystywano metodę graficzną jako pierwszy etap prac. Jednakże metoda ta ma pewne niedogodności. Przykładowo, nie uwzględnia występowania stref odprężania wokół przodka. Innym ograniczeniem metody graficznej jest to, iż nie może być ona wykorzystana do oceny stabilności przodków w których ściany zawierają materiał podsadzany. Istnieją jednak metody analityczne i numeryczne, które pozwalają na przezwyciężenie tych ograniczeń. W pracy tej wykorzystano zarówno metody empiryczne jak i numeryczne do oceny stabilności przodka wybierkowego zlokalizowanego pomiędzy poziomami N9225 i N9250 w podziemnej kopalni diamentów w Diavik. Wykazano, że metody numeryczne stanowią znakomite uzupełnienie metod analitycznych i empirycznych wykorzystywanych do oceny stabilności przodków wybierkowych. Opracowano trójwymiarowy model elastyczno-plastycznych elementów skończonych z wykorzystaniem oprogramowania Abaqus. W pracy tej przeprowadzono analizę wrażliwości i zbadano wpływ wskaźnika stosunku naprężeń "k" na zasięg osiadania i powstanie stref odprężenia wokół warstw stropu i spągu w badanym przodku wybierkowym.
Źródło:
Archives of Mining Sciences; 2017, 62, 3; 653-669
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A review of progress in current research on Chinese flowering cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee)
Autorzy:
Liu, W.
Liu, Y.
Kleiber, T.
Powiązania:
https://bibliotekanauki.pl/articles/1192785.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Tematy:
Chinese flowering cabbage
nutritional value
yield
breeding
Opis:
Chinese flowering cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) is an important leafy vegetable species, which originates from Guangdong province in southern China. There is a variety called purple Chinese flowering cabbage (Brassica campestris L. ssp. chinensis L. Makino var. purpurea Bailay), which is popular in the Yangtze River basin, e.g. in Wuhan and Sichuan provinces. This manuscript is a review of recent studies on the nutritional value, breeding methods and factors affecting the yield of Chinese flowering cabbage. This vegetable is rich in glucosinolates, polyphenols, amino acids, fatty acids, soluble sugar and vitamin C. It also exhibits some antioxidative activity, e.g. the TEAC value was 16.93 μmol Trolox g-1 and the FRAP value was 12.01 µmol Fe(II) g-1 in total. Controlling the Cd level in Chinese flowering cabbage is important due to the fact that it can easily accumulate Cd in its edible leaves and flowering stems. To reduce the effect given by Cd, foliar spray with trace elements had been studied. Moreover, nitrogen fertilizer, biofertilizer and several cultivation methods have been implemented to improve the yielding and nutritional value of Chinese flowering cabbage. Depending on the conditions, fertilisation increased the yield from 19.1% to 168%, whereas the fresh weight of a single plant varied from 0.835 kg to 1.683 kg and the average yielding in the field ranged from 7.857 t ha-1 to 19.1 t ha-1. In the last part of this paper, we reviewed the different breeding methods that have been used to develop new varieties of Chinese flowering cabbage meeting specific requirements, such as selecting a hybrid with kale to enrich the genotype, increase the resistance or discover a specific bolting gene. In brief, Chinese flowering cabbage has the potential for future research and commercial market.
Źródło:
Journal of Elementology; 2021, 26, 1; 149-162
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantitative analysis of the relationship between shear strength and fractal dimension of solidified dredger fill with different fly ash content under monotonic shear
Autorzy:
Yang, S.
Liu, W.
Liu, H.
Powiązania:
https://bibliotekanauki.pl/articles/258498.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
curing agent
fly ash
shear strength
fractal dimension
SEM
Opis:
The dredger fill of Shanghai Hengsha Island Dongtan is solidified by curing agents with different fly ash content, and the shear strength index of solidified dredger fill is measured by the direct shear test. The microscopic images of solidified dredger fill are obtained by using SEM. The microscopic images are processed and analyzed by using IPP, and the fractal dimension including particle size fractal dimension Dps, aperture fractal dimension Dbs and particle surface fractal dimension Dpr is calculated by fractal theory. The quantitative analysis of the relationship between shear strength index and fractal dimension of solidified dredger fill is done. The research results show that the internal friction angle and the cohesion are closely related to the fly ash content λ and the curing period T, and the addition of fly ash can improve the effect of curing agent; There is no obvious linear relationship between the internal friction angle and the three fractal dimensions; The smaller particle surface fractal dimension Dpr and particle size fractal dimension Dps, the larger aperture fractal dimension Dbs, the greater the cohesion, and the cohesion has a good linear relationship with three fractal dimensions, and the correlation coefficient R2 is above 0.91.
Źródło:
Polish Maritime Research; 2018, S 2; 132-138
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Degradation mechanism study of amine collectors in Fenton process by quantitative structure-activity relationship analysis
Autorzy:
Wang, X.
Liu, W.
Duan, H.
Powiązania:
https://bibliotekanauki.pl/articles/110363.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
amine collectors
Fenton process
QSAR
degradation mechanism
quantum chemistry
Opis:
In this study, advanced oxidation processes (AOPs), Fenton process, was applied to degrade ten amine collectors. The experimental results indicated that most of the tested amines could be removed rapidly and effectively at pH=4, while the degradation of quaternary ammonium compounds was less than others. To research the Fenton oxidation process, the degradation-rate constants of amine collectors were calculated by the pseudo-second order kinetic model, then which was used as the dependent variable to establish a quantitative structure activity relationship (QSAR) model. Meanwhile, 16 molecular structure descriptors and quantum mechanical parameters for amine collectors were simulated and analyzed by using Materials Studio software. The optimum QSAR model was established based on the partial least squares regression (PLS) method and confirmed by the statistics analysis. The model revealed that hydrogen bond acceptor (HBA) and the maximum values of electrophilic attack in C atom sites (f(-)c) were the major effect factors for the degradation-rate constants of amine collector.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 713-721
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental study on amplitude-frequency characteristic and basin stability of horizontally driven pendulum
Autorzy:
Jia, J.
Wu, Y.
Liu, W.
Xiao, J.
Powiązania:
https://bibliotekanauki.pl/articles/281610.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
horizontally driven pendulum system
bifurcation
basin stability
Opis:
In this article, an inverted pendulum system is set up to explore the dynamics of a horizontally driven pendulum which exhibits a great variety of dynamical behavior and appears in a wide range of applications in the field of engineering. The facility is efficient to experimentally explore two kinds of coexisting movement patterns in the horizontally driven pendulum, i.e. in-phase and anti-phase patterns between the angular velocity of the pendulum rod and the direction of the driving forces. Theoretical analysis is applied to reveal the regimes of the coexistence of the two movement patterns, which is promising to control the system to a desired pattern.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 3; 839-846
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The port service ecosystem research based on the Lotka-Volterra model
Autorzy:
Li, W.
Liu, W.
Xu, X.
Gao, Z.
Powiązania:
https://bibliotekanauki.pl/articles/259265.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
port service ecosystem
niche breadth
competitive co-evolution
mutually beneficial co-evolution
Opis:
Under the new normal of China’s economy, the competition among the port enterprises is not only the competition of the core competence of the port, the port industry chain or the port supply chain, but also the competition of the port service ecosystem. In this paper, the concept and characteristics of the port service ecosystem is discussed, a hierarchical model of the port service ecosystem is constructed. As an extended logistic model, Lotka-Volterra model is applied to study the competitive co-evolution and mutually beneficial co-evolution of enterprises in the port service ecosystem. This paper simulates the co-evolution of enterprises in the port service ecosystem by using MATLAB programming. The simulation results show that the breadth of the niche of the enterprises is changing with the change of the competition coefficient and the coefficient of mutual benefit in the port service ecosystem. Based on that, some proposals are put forward to ensure the healthy and orderly development of the port service ecosystem.
Źródło:
Polish Maritime Research; 2017, S 3; 86-94
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Conjugate numerical investigation of a miniature flat-plate evaporator of a capillary pumped loop for electronics cooling
Autorzy:
Wan, Z.
Liu, W.
Tu, Z.
Nakayama, A.
Powiązania:
https://bibliotekanauki.pl/articles/1933189.pdf
Data publikacji:
2008
Wydawca:
Politechnika Gdańska
Tematy:
capillary pumped loop
flat plate evaporator
sidewall effect heat transfer limit
cooling of electronic devices
Opis:
A capillary pumped loop (CPL) is a two-phase thermal control device applied in cooling electronic devices. A two-dimensional conjugate numerical model of a miniature flat-plate capillary evaporator is presented in order to describe liquid and vapor flow, heat transfer and phase change in the porous wick structure, liquid flow and heat transfer in the compensation cavity and heat transfer in the vapor grooves and the metallic wall. The entire evaporator is solved with the SIMPLE algorithm as a conjugate problem. The shape and location of the vapor-liquid interface inside the wick are calculated, and a side wall effect heat transfer limit is introduced to estimate the evaporator's heat transport capability. The influence of various wall materials on the evaporator's performance is discussed in detail. The results suggest that an evaporator with a combined wall is capable of dissipating high heat flux and stabilizing the temperature of electronic devices at a moderate temperature level.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2008, 12, 1-2; 5-19
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electrorefining of High Carbon Ferromanganese in Molten Salts to Produce Pure Ferromanganese
Autorzy:
Xiao, S.J.
Liu, W.
Gao, L.
Zhang, J.
Powiązania:
https://bibliotekanauki.pl/articles/353411.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
high carbon ferromanganese
electrorefining
molten salts
pure ferromanganese
Opis:
High carbon ferromanganese is used as a starting material to prepare pure ferromanganese by electrorefining in molten salts. High carbon ferromanganese was applied as the anode, molybdenum was the cathode and Ag/AgCl was the reference electrode. The anodic dissolution was investigated by linear polarization in molten NaCl-KCl system. Then potentiostatic electrolysis was carried out to produce pure ferromanganese from high carbon ferromanganese. The cathodic product was determined to be a mixture of manganese and iron by x-ray diffraction (XRD). The content of carbon in the product was analyzed by carbon and sulfur analyzer. The post-electrolysis anode was characterized by scanning electron microscope (SEM). The mechanism of the anode dissolution and the distribution of the main impurity of carbon and silicon after electrolysis were discussed.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 3; 1505-1509
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
3-D simulation of vertical-axial tidal current turbine
Autorzy:
Zhang, Z.
Ma, Y.
Jiang, J.
Liu, W.
Ma, Q.
Powiązania:
https://bibliotekanauki.pl/articles/260421.pdf
Data publikacji:
2016
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
tidal current energy
vertical-axial turbine
hydrodynamic performance
CFD
numerical simulation
3-D effect
Opis:
Vertical-axial tidal current turbine is the key for the energy converter, which has the advantages of simple structure, adaptability to flow and uncomplex convection device. It has become the hot point for research and application recently. At present, the study on the hydrodynamic performance of vertical-axial tidal current turbine is almost on 2-D numerical simulation, without the consideration of 3-D effect. CFD (Computational Fluid Dynamics) method and blade optimal control technique are used to improve accuracy in the prediction of tidal current turbine hydrodynamic performance. Numerical simulation of vertical-axial tidal current turbine is validated. Fixed and variable deflection angle turbine are comparatively studied to analysis the influence of 3-D effect and the character of fluid field and pressure field. The method, put the plate on the end of blade, of reduce the energy loss caused by 3-D effect is proposed. The 3-D CFD numerical model of vertical-axial tidal current turbine hydrodynamic performance in this study may provide theoretical, methodical and technical reference for the optimal design of turbine.
Źródło:
Polish Maritime Research; 2016, 4; 73-83
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measurable realistic image-based 3D mapping
Autorzy:
Liu, W.
Wang, J.
Wang, J. J.
Ding, W.
Almagbile, A.
Powiązania:
https://bibliotekanauki.pl/articles/130115.pdf
Data publikacji:
2011
Wydawca:
Stowarzyszenie Geodetów Polskich
Tematy:
three-dimensional map
multi-sensor
measurable image
virtual reality
mapa trójwymiarowa
multisensor
rzeczywistość
Opis:
Maps with 3D visual models are becoming a remarkable feature of 3D map services. High-resolution image data is obtained for the construction of 3D visualized models.The3D map not only provides the capabilities of 3D measurements and knowledge mining, but also provides the virtual experienceof places of interest, such as demonstrated in the Google Earth. Applications of 3D maps are expanding into the areas of architecture, property management, and urban environment monitoring. However, the reconstruction of high quality 3D models is time consuming, and requires robust hardware and powerful software to handle the enormous amount of data. This is especially for automatic implementation of 3D models and the representation of complicated surfacesthat still need improvements with in the visualisation techniques. The shortcoming of 3D model-based maps is the limitation of detailed coverage since a user can only view and measure objects that are already modelled in the virtual environment. This paper proposes and demonstrates a 3D map concept that is realistic and image-based, that enables geometric measurements and geo-location services. Additionally, image-based 3D maps provide more detailed information of the real world than 3D model-based maps. The image-based 3D maps use geo-referenced stereo images or panoramic images. The geometric relationships between objects in the images can be resolved from the geometric model of stereo images. The panoramic function makes 3D maps more interactive with users but also creates an interesting immersive circumstance. Actually, unmeasurable image-based 3D maps already exist, such as Google street view, but only provide virtual experiences in terms of photos. The topographic and terrain attributes, such as shapes and heights though are omitted. This paper also discusses the potential for using a low cost land Mobile Mapping System (MMS) to implement realistic image 3D mapping, and evaluates the positioning accuracy that a measureable realistic image-based (MRI) system can produce. The major contribution here is the implementation of measurable images on 3D maps to obtain various measurements from real scenes.
Źródło:
Archiwum Fotogrametrii, Kartografii i Teledetekcji; 2011, 22; 297-310
2083-2214
2391-9477
Pojawia się w:
Archiwum Fotogrametrii, Kartografii i Teledetekcji
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Low-Frequency Mechanical Spectroscopy of Lanthanum Cobaltite Based Mixed Conducting Oxides
Autorzy:
Wu, X. S.
Cao, J. F.
Chen, Z. J.
Liu, W.
Powiązania:
https://bibliotekanauki.pl/articles/355599.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mixed conducting oxides
mechanical properties
domain structure
phase transition
mechanical spectroscopy
internal friction
Opis:
The low-frequency mechanical spectra of lanthanum cobaltite based mixed conducting oxides have been measured using a computer-controlled inverted torsion pendulum. The results indicate that the internal friction spectra and shear modulus depend on the Sr doping contents (x). For undoped samples, no internal friction peak is observed. However, for La0.8Sr0.2CoO3-δ, three internal friction peaks (P2, P3 and P4) are observed. In addition to these peaks, two more peaks (P0 and P1) are observed in La0.6Sr0.4CoO3‒δ. The P0 and P1 peaks show characteristics of a phase transition, while the P2, P3 and P4 peaks are of relaxation-type. Our analysis suggests that the P0 peak is due to a phase separation and the P1 peak is related to the ferromagnetic–paramagnetic phase transition. The P2, P3 and P4 peaks are associated with the motion of domain walls. The formation of this kind of domain structure is a consequence of a transformation from the paraelastic cubic phase to the ferroelastic rhombohedral phase. With partial substitution of Fe for Co, only one peak is observed, which is discussed as a result of different microstructure.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 3; 1733-1738
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reducing the salinity impact on soilless culture of tomatoes using supplemental Ca and foliar micronutrients
Autorzy:
Saleh, S.
Liu, G.
Liu, M.
Liu, W.
Gruda, N.
He, H.
Powiązania:
https://bibliotekanauki.pl/articles/12688394.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Wydawnictwo Uniwersytetu Przyrodniczego w Lublinie
Tematy:
plant cultivation
tomato
Solanum lycopersicum
soilless culture
vegetative growth
fruit quality
yield
calcium supplementation
foliar application
foliar nutrition
micronutrient
salinity impact
salt stress
physiological parameter
Opis:
Salt stress is known as one of the most severe abiotic factors limiting the plant production all over the world. In this study, three additives: (i) supplemental Ca (5 mmol L–1) to nutrient solution, (ii) foliar application of micronutrients (Fe, Mn and Zn at 60, 160 and 110 mg L–1, respectively), and (iii) combination of both of them were evaluated aiming to reduce the negative impact of salt stress on tomato plants cultivated in a soilless culture and improve the internal quality of fruits. The obtained results show that salinity reduced vegetative growth and physiological parameters, fruit yield and its components, and even more lowered fruit market classification of tomatoes. Salinity treatment reduced most of essential macro- and micronutrients in tomato fruit, whilst Na content was increased. Tomato productivity and fruit quality were ameliorated under saline conditions by increasing Ca into nutrient solution and applying a foliar application of micronutrients. A combination of both additives ranked the first to alleviate the adverse effects of salinity on tomatoes, followed by solo supplemental Ca into saline nutrient solution. On the other hand, the internal fruit quality of antioxidant compounds, such as vitamin C, lycopene, α-carotene, β-carotene and lutein as well as acidity, total soluble solid and dry matter percent, were increased under saline conditions.
Źródło:
Acta Scientiarum Polonorum. Hortorum Cultus; 2019, 18, 3; 187-200
1644-0692
Pojawia się w:
Acta Scientiarum Polonorum. Hortorum Cultus
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An innovative technology for recovery of zinc, lead and silver from zinc leaching residue
Autorzy:
Zheng, Y.-X.
Lv, J.-F.
Liu, W.
Qin, W.-Q.
Wen, S.-M.
Powiązania:
https://bibliotekanauki.pl/articles/110688.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
zinc leaching residue
lead sulfate
zinc sulfate
reduction roasting
flotation
Opis:
Zinc leaching residue is a good source of zinc and has a great potential to be utilized. However, it is very difficult to recover lead, zinc and silver from the residue by traditional technologies. In this study, a new technology based on conversions of PbSO4 and ZnSO4 in the residue to their respective sulfides by reduction roasting with coal powder followed by a flotation treatment was developed. The effects of roasting temperature, coal dosage, reaction time and pyrite dosage were investigated at a laboratory scale. The results showed that the conversion extent of PbSO4 and ZnSO4 under the optimal experimental conditions was 71.89 and 69.76%, respectively. A flotation concentrate containing 39.13% Zn, 6.93% Pb and 973.54 g/Mg Ag was obtained from the treated material, and the recovery of Zn, Pb and Ag was 48.38, 68.23 and 77.41%, respectively. The tailing containing ZnFe2O4 or Fe3O4 could be either stockpiled or further disposed.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 2; 943-954
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Derivation of formulas in spherical trigonometry based on rotation matrix
Autorzy:
Hsieh, T. H.
Wang, S. Z.
Liu, W.
Zhao, J. S.
Chen, C. L.
Powiązania:
https://bibliotekanauki.pl/articles/116775.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
spherical trigonometry
rotation matrix
spherical triangle
formulas of spherical triangle
nautical mathematics
geometric method
spherical navigation
Astronavigation
Opis:
The formulas of spherical triangle, which are widely used to solve various navigation problems, are the important basic knowledge of nautical mathematics. Because the sine rules and the cosine rules for the sides are the fundamental formulas to derive the other spherical triangle formulas, they are also called the genetic codes of the spherical triangle formulas. In the teaching process, teachers usually use the geometric method to derive and prove these fundamental formulas. However, the derivation of geometric methods is complicated and difficult to understand. To improve the teaching process, this paper proposes the three-dimensional rotation method, which is based on conversion of two cartesian coordinate frames using the rotation matrices. This method can easily and simultaneously derive the sine rules, the cosine rules for the sides, and the five-part formulas (I), and is also helpful to solve different kinds of spherical navigation problems.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2019, 13, 3; 553-558
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Characterization of Metal Derivatives of 1,1,2,2-Tetranitraminoethane (TNAE)
Autorzy:
Zhu, C.
Meng, Z.
Xu, Z.
Liu, W.
Liu, Y.
Shi, X.
Xie, T.
Powiązania:
https://bibliotekanauki.pl/articles/358571.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
Ionic compound
1,1,2,2-tetranitraminoethane
thermal property
safety performance
thermal decomposition kinetics
Opis:
The introduction of anions and cations into energetic materials can significantly improve their physicochemical and energetic properties. The K, Zn, Ba, Cu and Pb salts of 1,1,2,2-tetranitraminoethane (TNAE) were synthesized using TNAE as the starting material, and were characterized by IR spectroscopy, NMR spectroscopy and elemental analysis. All of the energetic salts exhibited relatively high thermal stabilities (decomposition temperatures ranging from 195.1 °C to 279.3 °C) and high densities (ranging from 2.1 g·cm–3 to 3.7 g·cm–3). It was demonstrated that the introduction of metal ions conveys better thermal stability than covalent TNAE itself. More importantly, the Zn, Ba and Cu salts exhibited good thermal stability, high density, low sensitivity, and therefore have the potential to be a new class of insensitive, highly energetic explosives for practical applications.
Źródło:
Central European Journal of Energetic Materials; 2018, 15, 3; 435-444
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fast and effective extraction for equivalent shunt resistances of triple-junction concentrator solar cells
Autorzy:
Lv, H
Dai, J
Sheng, F
Liu, W
Ma, X
Cheng, C
Lv, Q
Powiązania:
https://bibliotekanauki.pl/articles/174425.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
concentrator photovoltaic
triple junction solar cell
equivalent shunt resistance
Opis:
Fast and effective extraction of equivalent shunt resistance for each subcell of GaInP/GaInAs/Ge triple-junction concentrator solar cells is presented. The two-diode model of single junction was introduced to establish the equivalent circuit of triple-junction solar cells. The current-voltage characteristic of the triple-junction solar cells was measured under AM1.5D spectrum, C = 576 and T = 303 K. Equivalent shunt resistance of each subcell was extracted from its estimated current-voltage curve. The estimated current-voltage curve of the triple-junction solar cells shows a good agreement with the experimental data in 0.31% deviation. The degradation in the equivalent shunt resistance for Ge subcell was intentionally introduced to indicate the mechanism of current-matching operation for different subcells, with the maximum output power of the triple-junction solar cells deteriorating from 3.5 to 3.17 W. The results can offer performance analysis and optimum design of photovoltaic applications.
Źródło:
Optica Applicata; 2015, 45, 2; 227-235
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prevalence of pathogenicity island ETT2 in Escherichia coli isolated from piglets with diarrhea in northeast of China
Autorzy:
Yuan, C.W.
Liu, W.X.
Hou, J.L.
Zhang, L.G.
Wang, G.Q.
Powiązania:
https://bibliotekanauki.pl/articles/2087783.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Escherichia coli
pathogenicity island
ETT2
piglets
diarrhea
Źródło:
Polish Journal of Veterinary Sciences; 2018, 21, 1; 5-12
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selective reduction of PbSO4 to PbS with carbon and flotation treatment of synthetic galena
Autorzy:
Zheng, Y.-X.
Liu, W.
Qin, W.-Q.
Han, J.-W.
Yang, K.
Luo, H.-L.
Powiązania:
https://bibliotekanauki.pl/articles/110717.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
wastes
lead sulfate
reduction
carbon
lead sulfide
flotation
Opis:
In order to recover lead from the zinc leaching residues, a new technology involving selective reduction of lead sulfate to lead sulfide with carbon followed by flotation was investigated. The reduction thermodynamics of PbSO4 was discussed and the effects of molar ratio of C to PbSO4, reaction temperature and time were examined by thermogravimetry (TG) and XRD. Verification tests were further carried out to prove the conclusions of thermodynamic and TG analyses, and the transformation extent could reach 86.45% under the optimal roasting conditions. The prepared galena was then subjected to micro-flotation tests, and the highest lead recovery could reach up to 75.32%.
Źródło:
Physicochemical Problems of Mineral Processing; 2015, 51, 2; 535-546
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of organic supplementation to reduced rates of chemical fertilization on soil fertility of Zanthoxylum armatum
Autorzy:
Saba, T.
Liu, W.
Wang, J.
Saleem, F.
Kang, X.
Hui, W.
Gong, W.
Li, H.
Powiązania:
https://bibliotekanauki.pl/articles/2130175.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
fertilization
soil fertility
nutrient availability
organic manure
culturable microbes
Opis:
Soil acidification, fertility depletion, food insecurity, and environmental pollution all are consequences of the extensive use of chemical fertilizers (CF) in intensively managed plantations. Recent studies have shown that incorporating organic manure (OM) to partially replace CF can help to maintain productivity and soil health. There are no reports on integrated fertilizer management of Zanthoxylum armatum, for optimal ecological services and economic profitability. A pot experiment with Z. armatum was performed to investigate the possibility of incorporating OM in reducing CF use, enhancing soil fertility, and increasing plant growth. For this, seven treatments were designed: NPK, PK, NP, NK, OM, MNPK (50%NPK+50%OM), and control (CK, no fertilizer application). The results showed that NPK application significantly (P < 0.05) increased plant growth, soil nitrate-N, ammonium-N and available K compared to CK. However conventional CF application induced soil acidification. OM application raised the soil pH from 5.50 (CK) to 6.58 and significantly enhanced soil fertility by increasing alkali-hydrolysable N (2.3 times), ammonium-N (1.4 times), available P (4.3 times), the activity of invertase (1.5 times), catalase (2.8 times), acid phosphatase (1.5 times), and count of soil culturable microbes (2.9 times) compared to CK. Conversely, sole OM application did not result in optimum plant growth. Integrating OM with NPK (MNPK), on the other hand, not only provided the highest growth comprehensive value (0.84), but also substantially higher soil fertility comprehensive value (0.71) than traditional CF treatments. Correlation analysis also indicated a positive and significant correlation between soil microbes, enzyme activities and available nutrients. Therefore, OM+NPK could be an optimum measure to get maximum benefits regarding soil fertility, growth of Z. armatum, fertilizer savings and sustainable agroecology.
Źródło:
Dendrobiology; 2022, 87; 123-136
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genome-wide association study of terpenoids in resin reveals candidate genes for resin yield in Pinus massoniana
Autorzy:
Bai, Q.
Zhang, Q.
Cai, Y.
Lian, H.
Liu, W.
Luo, M.
Zeng, L.
He, B.
Powiązania:
https://bibliotekanauki.pl/articles/2078149.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Pinus massoniana
GC-MS
terpenoid
GWAS
candidate gene
Opis:
Masson pine (Pinus massoniana) is an important species for resin tapping in China. Molecular assisted selection (MAS) has been gradually introduced in to the selection and breeding of masson pine. Until now, the lack of connection between genome information and phenotypic data has hindered the breeding and selection of important chemical compounds of xylem resin. In this study, gas chromatography mass spectrometer (GC-MS) was employed for qualitative and quantitative analysis of chemical compounds of resin collected from 69 masson pine germplasm resources. Then, genome-wide association study (GWAS) was conducted for the terpenoids with higher heritability. A total of 15 primary compounds, including six diterpenes and nine monoterpenes/sesquiterpenes, were detected from xylem resin. By using five GWAS methods, 42 associated SNPs were identified from these masson pines. The P. taeda genome database was used for detecting candidate genes related to the associated SNPs. By using transcriptome data, several members of PKc_like super family, Cytochrome P450, AP2-ERF, F-box, and ABC transporter were found to be highly expressed in the masson pines with higher resin-yielding capacity. The terpenoids associated SNPs can be directly used for MAS. These candidate genes, especially the two F-box members, will contribute to the study of terpenoid biosynthesis mechanisms in the future.
Źródło:
Dendrobiology; 2020, 84; 109-121
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A New Star-Like SurfaceTexture for Enhanced Hydrodynamic Lubrication Performance
Autorzy:
Uddin, M. S.
Liu, Y. W.
Shankar, S.
Powiązania:
https://bibliotekanauki.pl/articles/356465.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
surface texturing
friction
film pressure
numerical modelling
Reynolds equation
Opis:
This paper presents a numerical modelling and optimization of a new ‘star-like’ geometric texture shape with an aim to improve tribological performance. Initial studies showed that the triangle effect is the most dominant in reducing the friction. Motivated with this, a ‘star-like’ texture shape consisting of a series of triangular spikes around the centre of the texture is proposed. It is hypothesised that by increasing the triangular effect on a texture shape, the converging micro-wedge effect is expected to increase, hence increasing the film pressure and reducing the friction. Using the well-known Reynolds boundary conditions, numerical modelling of surface texturing is implemented via finite difference method. Simulation results showed that the number of apex points of the new ‘star-like’ texture has a significant effect on the film pressure and the friction coefficient. A 6-pointed texture at a texture density of 0.4 is shown to be the optimum shape. The new optimum star-like texture reduces the friction coefficient by 80%, 64.39%, 19.32% and 16.14%, as compared to ellipse, chevron, triangle and circle, respectively. This indicates the potential benefit of the proposed new shape in further enhancing the hydrodynamic lubrication performance of slider bearing contacts.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 3; 1863-1869
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ca-Modified Co/SBA-15 Catalysts for Hydrogen Production through Ethanol Steam Reforming
Autorzy:
Chiou, J. Y. Z.
Liu, S. W.
Ho, K. F.
Huang, H. H.
Tang, Ch. W.
Wang, Ch. B.
Powiązania:
https://bibliotekanauki.pl/articles/411682.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
cobalt catalysts
ethanol
steam reforming
Opis:
Hydrogen production through steam reforming of ethanol (SRE) over the Ca-modified Co/SBA-15 catalysts was studied herein to evaluate the catalytic activity, stability andthebehavior of coke deposition.The Ca-modified SBA-15 supports were prepared from the Ca(NO3)2•4H2O (10 wt%) which was incorporated to SBA-15 by incipient wetness impregnation (assigned as Ca/SBA-15) and direct hydrothermal (assigned as Ca-SBA-15) method. The active cobalt species from the Co(NO3)2•6H2O (10 wt%) was loaded to SiO2, SBA-15 and modified-SBA-15 supports with incipient wetness impregnation method to obtain the cobalt catalysts (named as Co/SiO2, Co/SBA-15, Co-Ca/SBA-15 and Co/Ca-SBA-15, respectively). The prepared catalysts were characterized by using X-ray diffraction (XRD), temperature programmed reduction (TPR), transmission electron microscopy (TEM) and BET.The catalytic performance of the SRE reaction was evaluated in a fixed-bed reactor.The results indicated that the Co/Ca-SBA-15 catalystwas preferential among these catalysts and the ethanol can be converted completely at 375 °C. The hydrogen yield (YH2) approached 4.76 at 500 °C and less coke deposited. Further, the long-term stabilitytest of this catalyst approached100h at 500 °C and did not deactivate.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 5; 1-16
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth and characterisation of LWIR T2SL on (100)-, (211)- and (311)-oriented GaSb substrates
Autorzy:
Lubyshev, Dmitri
Fastenau, Joel M.
Kattner, Michael
Frey, Philip
Nelson, Scott A.
Flick, Ryan
Wu, Ying
Liu, Amy W. K.
Szymanski, Dennis E.
Martinez, Becky
Furlong, Mark J.
Dennis, Richard
Bundas, Jason
Sundaram, Mani
Powiązania:
https://bibliotekanauki.pl/articles/2204213.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Tematy:
focal plane arrays
InAs/InAsSb
photodetectors
long wavelength infrared type-II superlattice
metamorphic buffers
superlattice period reduction
Opis:
Ga-free InAs/InAsSb type-II superlattice structures grown on GaSb substrates have demonstrated high performance for mid-wave infrared applications. However, realisation of long wavelength infrared photodetectors based on this material system still presents challenges, especially in terms of reduced quantum efficiency. This reduction is due, in part, to the increased type-II superlattice period required to attain longer wavelengths, as thicker periods decrease the wave-function overlap for the spatially separated quantum wells. One way to improve long wavelength infrared performance is to modify the type-II superlattice designs with a shorter superlattice period for a given wavelength, thereby increasing the wave-function overlap and the resulting optical absorption. Long wavelength infrared epitaxial structures with reduced periods have been realised by shifting the lattice constant of the type-II superlattice from GaSb to AlSb. Alternatively, epitaxial growth on substrates with orientations different than the traditional (100) surface presents another way for superlattice period reduction. In this work, the authors evaluate the performance of long wavelength infrared type-II superlattice detectors grown by molecular beam epitaxy using two different approaches to reduce the superlattice period: first, a metamorphic buffer to target the AlSb lattice parameter, and second, structures lattices matched to GaSb using substrates with different orientations. The use of the metamorphic buffer enabled a ~30% reduction in the superlattice period compared to reference baseline structures, maintaining a high quantum efficiency, but with the elevated dark current related to defects generated in the metamorphic buffer. Red-shift in a cut-off wavelength obtained from growths on highindex substrates offers a potential path to improve the infrared photodetector characteristics. Focal plane arrays were fabricated on (100), (311)A- and (211)B-oriented structures to compare the performance of each approach.
Źródło:
Opto-Electronics Review; 2023, 31, Special Issue; art. no. e144568
1230-3402
Pojawia się w:
Opto-Electronics Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation and experimental study in the process of wave energy conversion
Autorzy:
Zhang, W.
Liu, Y.
Powiązania:
https://bibliotekanauki.pl/articles/260115.pdf
Data publikacji:
2016
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
wave energy converter
suitable control technology
experimental verification
Opis:
This article introduces the operating principle of the wave energy device and makes AMEsim simulated analysis in the influence of the amplitude and period of the wave on the output efficient. By using the result of the simulation to optimize design, the article puts forwards a kind of suitable control technology which based on the disclosed amplitude and period of the wave to control the check valve, invoking the motor in different levels of efficiency. This kind of technology aims to solve the problem which includes low efficiency and high start wave of the wave energy device. The result is verified by the physical experiment, which lays the foundation for the implementation of marine engineering. The established methods of simulation model and analysis results are expected to be useful to designing and manufacturing of wave energy converter.
Źródło:
Polish Maritime Research; 2016, S 1; 123-130
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Non-Markovian Dynamic of Gaussian Quantum Discord in Continuous-Variable Systems
Autorzy:
Liu, X.
Wu, W.
Powiązania:
https://bibliotekanauki.pl/articles/1203878.pdf
Data publikacji:
2014-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
03.65.Yz
03.65.Ta
03.65.Ud
03.67.Mn
Opis:
We show the special dynamic characteristic of Gaussian quantum discord, exhibited by two-mode Gaussian symmetric squeezed thermal states (STS) in continuous-variable (CV) systems with a common non-Markovian environment, is definitely different from Markov processes. We demonstrate that Gaussian quantum discord can be created whenever the information flow from environment back to the system. We also show that the rate of decrease for Gaussian quantum discord is related to the coupling constant. We discover that the initial value of Gaussian quantum discord is determined by the average number of thermal photons of the system.
Źródło:
Acta Physica Polonica A; 2014, 126, 3; 652-655
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of pH on surface characteristics and flotation of sulfidized cerussite
Autorzy:
Feng, Q.
Wen, S.
Zhao, W.
Liu, J.
Liu, D.
Powiązania:
https://bibliotekanauki.pl/articles/110234.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
cerussite
sulfidization
excessive sulfide ions
pH
surface analysis
Opis:
The effect of pH on surface characteristic and flotation of sulfidized cerussite was studied by micro-flotation tests, dissolution experiments, scanning electron microscopy (SEM) energy dispersive spectrometer (EDS), and X-ray photoelectron spectroscopy (XPS). The micro-flotation tests demonstrated that higher recovery of cerussite was achieved in acidic solutions than that in alkaline solutions. Despite the addition of high collector concentrations, cerussite flotation did not improved in alkaline solutions. The dissolution performance of sulfide-treated cerussite at different pH values indicated that the lead sulfide layer on the surface of sulfide-treated cerussite could exist in acidic solutions and it was more stable at acidic pH than in alkaline solutions. This finding was proved by the SEM-EDS and XPS analyses.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 2; 676-689
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Towards the building information modeling-based capital project lifecycle management in the luxury yacht industry
Autorzy:
Liu, F.
Chen, C.
Wu, W.
Powiązania:
https://bibliotekanauki.pl/articles/259822.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
building information modelling
luxury yacht
communication
interoperability
capital
project lifecycle management
framework
Opis:
It will be a new approach that BIM’s capital project lifecycle management (CPLM) applied to the yacht industry. This paper explored the feasibility of applying the principles and rationales of BIM for capital project lifecycle management in luxury yacht design, engineering, fabrication, construction and operation. The paper examined the premises and backbone technology of BIM. It then evaluated leading naval engineering and shipbuilding software applications and their development trends from the functional lens of BIM. To systematically investigate a BIM-based approach for capital project lifecycle management (CPLM) in the luxury yacht industry, the paper proposed and outlined an implementation framework. A case study and a student competition use case were discussed to delineate the core constituents and processes of the proposed framework. The case of BIM was reviewed. Through the domestic custom luxury yacht design and prototyping student competition, the application of this framework in educational research is demonstrated and the initial quantitative assessment of the framework is carried out. Conclusions: a BIM-based CPLM implementation framework can help the luxury yacht industry capitalize on the global transformation to an information-centric and data-driven new business paradigm in shipbuilding with integrated design, manufacturing and production.
Źródło:
Polish Maritime Research; 2017, S 3; 41-48
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phase change of chlorite in reducing atmosphere
Autorzy:
Liu, X.
Yu, Y.
Chen, W.
Powiązania:
https://bibliotekanauki.pl/articles/110704.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
chlorite
phase change
magnetizing
reducing roasting
magnetite
Opis:
Magnetizing roasting is an important pre-treatment technique for beneficiation of hematite and limonite ores. Reduction mechanisms of these iron minerals have been fully studied while the mechanism of reduction of chlorite is not well understood. In this study, a reduction roasting study examining the phase change of chlorite with roasting temperature was undertaken. The major finding from this study was that chlorite partially was reduced to magnetite by carbon at 750 ⁰C, and the newly formed magnetite was finely disseminated within quartz and olivine. It was demonstrated that these locked magnetite particles would be reported to iron concentrate by low intensity magnetic separation resulting in high impurity content, especially SiO2 and Al2O3 contents in the concentrate.
Źródło:
Physicochemical Problems of Mineral Processing; 2014, 50, 2; 607-614
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A multiscale methodology for CFD simulation of catalytic distillation bale packings
Autorzy:
Ding, H.
Xiang, W.
Liu, Ch.
Powiązania:
https://bibliotekanauki.pl/articles/780059.pdf
Data publikacji:
2016
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
multiscale model
CFD
reactive distillation
Opis:
A multiscale model for simulating the hydrodynamic behavior of catalytic bale packings has been proposed. This model combines computational fluid dynamics (CFD) and macroscopic calculation. At small scale calculation, the CFD model includes 3-D volume-of-fluid (VOF) simulation within representative elementary unit (REU) under unsteady-state conditions. The REU constitutes gauze and catalyst domain, and porous media model is applied. At large scale calculation, a new mechanistic model deduced from the unit network model is employed. Based on liquid split proportion from small scale calculation, liquid distribution of the entire bale packing can be predicted. To evaluate different packing design, three common bale arrangements, i.e. one-bale, nine-bales and seven-bales, are compared. The area-weighted Christiansen uniformity coefficient is introduced to assess the distribution performance. A comparison between simulation and experimental results is made to validate the multiscale model. The present methodology is proved to be effective to analysis and design of catalytic distillation columns.
Źródło:
Polish Journal of Chemical Technology; 2016, 18, 1; 24-32
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Global Thermoeconomics
Autorzy:
Cardullo, Mario W.
Liu, Manhong Mannie
Powiązania:
https://bibliotekanauki.pl/articles/565709.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Warszawski. Wydawnictwo Naukowe Wydziału Zarządzania
Tematy:
Thermodynamics
Labor Theory of Value
Labor Value Equation
Global Reserve
Currency
Financial Stability
Employment
Asset Valuation
Productivity
Opis:
This paper illustrates that basic global economic concepts can be directly related to the First and Second Laws of Thermodynamics. We believe that all economic returns are from nothing except from current and past human expenditure of human energy; this is the result of the First Law of Thermodynamics. It is shown that everything is a product of energy in the form of labor and that the basic principle of Labor Theory of Value is still valid and this principle is validated not relying on economics and fi nance models, rather on thermodynamic principles. This is illustrated by the development of the Labor Value Equation based on the application of the First and Second Law of Thermodynamics and how it can impact employment, asset valuation, supply/demand, productivity, global confl ict, global reserve currency and global stability
Źródło:
Journal of Banking and Financial Economics; 2017, 1(7); 70-89
2353-6845
Pojawia się w:
Journal of Banking and Financial Economics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New Development of Ships Routeing in Chinese Navigable Waterways
Autorzy:
Hui, M.
Zhaolin, W.
Zhengjiang, Liu
Powiązania:
https://bibliotekanauki.pl/articles/116736.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Ships Routeing
Chinese Navigable Waterways
Marine Traffic Engineering (MTE)
vessel traffic service (VTS)
Traffic Separation Scheme (TSS)
Marine Traffic
Marine Traffic Safety
Safety of Navigation
Opis:
After entering 21 century Chinese waterborne transportation keep high speed development, mmarine traffic order and marine traffic safety become more important issues. In order to enhance marine traffic safety and efficiency, ships routeing systems were implemented in important navigable waters in recent years. After implementation of these ships routeing systems, evaluations on the effects are carried and prove that these ships routeing systems have got obvious effects both on safety and economic efficiency.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2008, 2, 2; 127-130
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stochastic hopf bifurcation of quasi-integrable hamiltonian systems with time-delayed feedback control
Stochastyczna bifurkacja Hopfa w quasi-całkowalnych układach Hamiltonowskich sterowanych w pętli sprzężenia zwrotnego z opóźnieniem
Autorzy:
Liu, Z. H.
Zhu, W. Q.
Powiązania:
https://bibliotekanauki.pl/articles/280917.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
stochastyczna bifurkacja Hopfa
quasi-całkowalny układ Hamiltonowski
sprzężenie zwrotne z opóźnieniem
stochastic Hopf bifurcation
quasi-integrable Hamiltonian system
stochastic averaging
time-delayed feedback control
Opis:
The stochastic Hopf bifurcation of multi-degree-of-freedom (MDOF) quasi-integrable Hamiltonian systems with time-delayed feedback control subject to Gaussian white noise excitations is studied. First, the time-delayed feedback control forces are approximately expressed in terms of the system state variables without time delay, and the system is converted into anordinary quasi-integrable Hamiltonian system. The averaged It�o stochastic differential equations are derived by using the stochastic averaging method for quasi-integrable Hamiltonian systems. Then, an expression for the average bifurcation parameter of the averaged system is obtained approximately, and a criterion for determining the stochastic Hopf bifurcation caused by the time-delayed feedback control forces in the original system as the value of the average bifurcation parameter changing is proposed. An example is worked out in detail to illustrate the above criterion and its validity, and to show the effect of the time delay in the feedback control on the stochastic Hopf bifurcation of the system.
W pracy zajęto się problemem stochastycznej bifurkacji Hopfa quasi-całkowalnych układów Hamiltonowskich o wielu stopniach swobody poddanych wymuszeniu białym szumem z układem sterowania opartym na pętli sprzężenia zwrotnego z opóźnie- niem. Najpierw znaleziono przybliżone wyrażenia na siły sterujące w funkcji zmiennych stanu układu bez opóźnienia, a następnie przetransformowano go postaci quasi- całkowalnej, Hamiltonowskiej. Wyprowadzono stochastyczne równania różniczkowe It^o za pomocą metody uśredniania układów quasi-całkowalnych. Znaleziono przybliżoną postać wyrażenia na parametr bifurkacyjny uśrednionego układu i zaproponowano kryterium stwierdzające obecność stochastycznej bifurkacji Hopfa wywołanej siłami sterującymi z opóźnieniem na podstawie wartości zmiany tego parametru. Opracowa- no szczegółowo przykład do ilustracji działania tego kryterium i zakresu jego stosowalności oraz do prezentacji wpływu opóźnienia w pętli sterownia na stochastyczną bifurkację Hopfa badanego układu.
Źródło:
Journal of Theoretical and Applied Mechanics; 2008, 46, 3; 531-550
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inversion of side scan sonar motion and posture in seabed geomorphology
Autorzy:
Tao, W.
Liu, Y.
Hu, H.
Powiązania:
https://bibliotekanauki.pl/articles/258774.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
side scan sonar
image matching
image fusion
neutral network
motion inversion
Opis:
Side scan sonar measurement platform, affected by underwater environment and its own motion precision, inevitably has posture and motion disturbance, which greatly affects accuracy of geomorphic image formation. It is difficult to sensitively and accurately capture these underwater disturbances by relying on auxiliary navigation devices. In this paper, we propose a method to invert motion and posture information of the measurement platform by using the matching relation between the strip images. The inversion algorithm is the key link in the image mosaic frame of side scan sonar, and the acquired motion posture information can effectively improve seabed topography and plotting accuracy and stability. In this paper, we first analyze influence of platform motion and posture on side scan sonar mapping, and establish the correlation model between motion, posture information and strip image matching information. Then, based on the model, a reverse neural network is established. Based on input, output of neural network, design of and test data set, a motion posture inversion mechanism based on strip image matching information is established. Accuracy and validity of the algorithm are verified by the experimental results.
Źródło:
Polish Maritime Research; 2017, S 2; 81-88
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An integrated production and delay-time based preventive maintenance planning model for a multi-product production system
Model integrujący planowanie opartej na pojęciu czasu opóźnienia konserwacji zapobiegawczej oraz planowanie produkcji dla systemów produkcji wieloasortymentowej
Autorzy:
Liu, X.
Wang, W.
Peng, R.
Powiązania:
https://bibliotekanauki.pl/articles/1365965.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
production planning
preventive maintenance
delay time
integration
multi-product
planowanie produkcji
konserwacja zapobiegawcza
czas opóźnienia
integracja
wieloasortymentowy
Opis:
This paper integrates preventive maintenance and medium-term tactical production planning in a multi-product production system. In such a system, a set of products needs to be produced in lots during a specified finite planning horizon. Preventive maintenance is carried out periodically at the end of some production periods and corrective maintenance is always performed at failures. The system’s available production capacity can be affected by maintenance, since both planned preventive maintenance and unplanned corrective maintenance result in downtime loss during the planning horizon. In addition to the time used for preventive and corrective maintenance, our model considers the setup time and the product quality, as these are affected by the defects and failures of the system. Procedures are proposed to identify the optimal production plan and preventive maintenance policy simultaneously. Our objective is to minimize the sum of maintenance, production, inventory, setup, backorder costs and the costs of unqualified products within the planning horizon. A real case from a steel factory is presented to illustrate the model.
W niniejszej pracy zintegrowano proces konserwacji zapobiegawczej z procesem średnioterminowego taktycznego planowania produkcji w odniesieniu do systemu produkcji wieloasortymentowej. W takim systemie, zestaw wyrobów jest produkowany partiami w określonym, skończonym horyzoncie planowania. Konserwacja zapobiegawcza prowadzona jest okresowo pod koniec wybranych okresów produkcyjnych, natomiast w przypadku wystąpienia uszkodzenia wykonuje się konserwację korygującą. Konserwacja może mieć wpływ na dostępne moce produkcyjne systemu, jako że zarówno planowana konserwacja prewencyjna jak i nieplanowana konserwacja korygująca powodują straty związane z przestojem urządzeń w danym horyzoncie planowania. Oprócz czasu potrzebnego na konserwację zapobiegawczą i korygującą, nasz model uwzględnia czas konfiguracji urządzeń oraz jakość produktów, ponieważ one również zależą od defektów i awarii systemu. Zaproponowano procedury, które pozwalają na jednoczesne określenie optymalnego planu produkcji i optymalnej strategii konserwacji prewencyjnej. Naszym celem jest minimalizacja sumy kosztów konserwacji, produkcji, zapasów, konfiguracji urządzeń oraz zamówień oczekujących a także kosztów produktów, które nie zostały zakwalifikowane do wprowadzenia do obrotu w danym horyzoncie planowania. Model zilustrowano na przykładzie rzeczywistego przypadku z fabryki stali.
Źródło:
Eksploatacja i Niezawodność; 2015, 17, 2; 215-221
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Właściwości antykorozyjne żywic styrenowo-akrylowych zawierających tripolifosforan glinu
Anticorrosive properties of styrene-acrylic resins containing aluminum tripolyphosphate
Autorzy:
Shangguan, L. J.
Ma, W.
Liu, G.
Song, W.
Powiązania:
https://bibliotekanauki.pl/articles/142544.pdf
Data publikacji:
2015
Wydawca:
Stowarzyszenie Inżynierów i Techników Przemysłu Chemicznego. Zakład Wydawniczy CHEMPRESS-SITPChem
Tematy:
żywice styrenowo-akrylowe
tripolifosforan glinu
właściwości antykorozyjne
otrzymywanie
styrene-acrylic resins
aluminum tripolyphosphate
anticorrosive properties
preparation
Opis:
Tripolifosforan glinu zdyspergowano w emulsji styrenowo-akrylowej. Rozkład i wielkości cząstek lateksu badano za pomocą laserowego analizatora cząstek. Właściwości antykorozyjne układu żywice styrenowo-akrylowe – tripolifosforan glinu badano za pomocą elektrochemicznej spektroskopii impedacyjnej (EIS), próby w komorze solnej według normy ASTM B-117 oraz testów adhezji. Wyniki wskazują na wzmocnienie działania ochronnego żywic styrenowo-akrylowych po dodaniu tripolifosforanu glinu.
Aluminum tripolyphosphate was introduced into the dispersion solution of styrene-acrylic emulsion The laser particle size analyzer was used to analyse the distribution and particles size of the latex particle. The anticorrosion performance of styrene-acrylic resins/aluminum tripolyphosphate was studied using electrochemical impedance spectroscopy (EIS), salt spray standard test according to ASTM B-117 and adhesion tests. The results indicated the protective performance of styrene-acrylic resins was improved by adding aluminum tripolyphosphate.
Źródło:
Chemik; 2015, 69, 9; 578-585
0009-2886
Pojawia się w:
Chemik
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation and characterization of high count yak wool yarns spun by complete compacting spinning and fabrics knitted from them
Przygotowanie i charakterystyka przędz o dużej masie liniowej z wełny jaków przędzionych systemem kompaktowym rotorowym oraz dzianiny wykonane z tych przędz
Autorzy:
Li, W.
Liu, X.
Liu, C.
Su, X.
Xie, C.
Wei, Q.
Powiązania:
https://bibliotekanauki.pl/articles/232629.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
yak wool
pure high count yarns
complete compacting spinning
CCS
yarn quality
knitted wearability
przędza z jaka
przędzenie kompaktowe
przędzenie obrączkowe
jakość przędzy
Opis:
The attentions of the textile industry has been attracted by yak wool due to its excellent properties, environmental friendly characteristics and inexpensive prices. However, the processing of yak wool is difficult due to the larger fiber dispersion and stiffness, especially spun pure and high count yak wool yarn. Therefore, in this paper, a kind of roller-type compact spinning - complete compacting spinning (CCS) was applied to spun pure high count yak wool yarns, in which a special hollow roller made of stainless steel with a strip groove structure on its surface was employed. Based on the mechanism of CCS, the processing parameters for two kinds of yak wool yarns - 20.83 tex and 16.67 tex were set. Then the qualities of the yarns prepared were tested and compared with yak wool yarns spun by common ring spinning. Finally corresponding knitted fabrics were further produced and tested for wearability.
Przemysł włókienniczy zainteresowany jest produkcją przędzy z jaków dzięki jej dobrej właściwości termicznej, przyjaznych ekologicznie warunkom hodowli i niskim cenom. Jednakże przetwarzanie wełny jaków jest trudne ze względu na duże rozrzuty właściwości tych włókien i ich sztywność co uwidacznia się szczególnie przy przędzeniu wełny jaków o dużych masach liniowych. Dla rozwiązania tego zagadnienia opracowano specjalny system przędzenia oparty na przędzeniu kompaktowym z zastosowaniem wydrążonego wałka ze stali kwasoodpornej ze szczeliną o odpowiedniej strukturze na jego powierzchni. Przedstawiono wytwarzanie przędz o masie liniowej ok. 20,8 tex i 16,7 tex. Właściwości wyprzędzionych przędź porównano z właściwościami przędz otrzymanych za pomocą konwencjonalnego przędzenia obrączkowego. Badania zakończono wyprodukowaniem i sprawdzeniem właściwości użytkowych różnych wyrobów dziewiarskich.
Źródło:
Fibres & Textiles in Eastern Europe; 2016, 1 (115); 30-35
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Soil texture distribution simulation and risk assessment using transition probability-based geostatistics
Autorzy:
Li, X.
Liu, J.
Zhang, J.
Wang, W.
Xin, W.
Powiązania:
https://bibliotekanauki.pl/articles/24270.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
soil texture
conditional simulation
risk assessment
transition probability
geostatistics
Opis:
Three dimensional soil textural structure in a township was conditionally simulated using a transition pro- bability-based indicator geostatistical method based on 270 soil texture samples from 27 profiles. Additionally the distribution of soil profiles lacking clay interlayers (indicating high irrigation water and nutrient leaching risk) was analyzed using 500 realizations from the simulation. The results indicated that the simulation could predict the soil texture distribution with low uncertainties using the existing data, and the predicted soil map (0-10 cm) formed by the maximum probable soil textures also exhibited a good agreement with the legacy soil survey map. For water and nutrient leaching risk analysis, the areas lacking clay interlayer could be located; however, their distribution was still highly uncertain if based only on the existing sampling data. That means supplementary sampling in future is required for the risk assessment, and the existing study can help to optimise the sampling points and their distribution. Generally, the transition probability-based geostatistical simulation, as a stochastic conditional simulation method, exhibited its potential in soil texture spatial reproduction and related risk assessment.
Źródło:
International Agrophysics; 2014, 28, 4
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydrogen sulfide is involved in the chilling stress response in Vitis vinifera L.
Autorzy:
Fu, P.
Wang, W.
Hou, L.
Liu, X.
Powiązania:
https://bibliotekanauki.pl/articles/56519.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
hydrogen sulphide
chilling stress
stress response
Vitis vinifera
Opis:
Hydrogen sulfide (H2S) is an important signaling molecule involved in several stress-resistance processes in plants, such as drought and heavy metal stresses. However, little is known about the roles of H2S in responses to chilling stress. In this paper, we demonstrated that chilling stress enhance the H2S levels, the H2S synthetase (L-/D-cysteine desulfhydrase, L/DCD) activities, and the expression of L/DCD gene in Vitis vinifera L. ‘F-242’. Furthermore, the seedlings were treated with sodium hydrosulfide (NaHS, a H2S donor) and hypotaurine (HT, a H2S scavenger) at 4°C to examine the effects of exogenous H2S on grape. The results revealed that the high activity of superoxide dismutase and enhanced expression of VvICE1 and VvCBF3 genes, but low level of superoxide anion radical, malondialdehyde content and cell membrane permeability were detected after addition of NaHS. In contrast, HT treatment displayed contrary effect under the chilling temperature. Taken together, these data suggested that H2S might be directly involved in the cold signal transduction pathway of grape.
Źródło:
Acta Societatis Botanicorum Poloniae; 2013, 82, 4
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Accurate Frequency Estimation Based On Three-Parameter Sine-Fitting With Three FFT Samples
Autorzy:
Liu, X.
Ren, Y.
Chu, C.
Fang, W.
Powiązania:
https://bibliotekanauki.pl/articles/220451.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
frequency estimation
CRLB
three-parameter sine-fitting
RMSE
golden section
Opis:
This paper presents a simple DFT-based golden section searching algorithm (DGSSA) for the single tone frequency estimation. Because of truncation and discreteness in signal samples, Fast Fourier Transform (FFT) and Discrete Fourier Transform (DFT) are inevitable to cause the spectrum leakage and fence effect which lead to a low estimation accuracy. This method can improve the estimation accuracy under conditions of a low signal-to-noise ratio (SNR) and a low resolution. This method firstly uses three FFT samples to determine the frequency searching scope, then – besides the frequency – the estimated values of amplitude, phase and dc component are obtained by minimizing the least square (LS) fitting error of three-parameter sine fitting. By setting reasonable stop conditions or the number of iterations, the accurate frequency estimation can be realized. The accuracy of this method, when applied to observed single-tone sinusoid samples corrupted by white Gaussian noise, is investigated by different methods with respect to the unbiased Cramer-Rao Low Bound (CRLB). The simulation results show that the root mean square error (RMSE) of the frequency estimation curve is consistent with the tendency of CRLB as SNR increases, even in the case of a small number of samples. The average RMSE of the frequency estimation is less than 1.5 times the CRLB with SNR = 20 dB and N = 512.
Źródło:
Metrology and Measurement Systems; 2015, 22, 3; 403-416
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improved dynamic control method for energy storage units in PV dominated microgrids
Autorzy:
Wang, Q.
Liu, Y.
Song, W.
Xuan, K.
Powiązania:
https://bibliotekanauki.pl/articles/141382.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
current correction coefficient
load distribution
PV DC microgrid
secondary control
weighted calculation
Opis:
In a PV-dominant DC microgrid, the traditional energy distribution method based on the droop control method has problems such as output voltage drop, insufficient power distribution accuracy, etc. Meanwhile, different battery energy storage units usually have different parameters when the system is running. Therefore, this paper proposes an improved control method that introduces a reference current correction factor, and a weighted calculation method for load power distribution based on the parameters of battery energy storage units is proposed to achieve weighted allocation of load power. In addition, considering the variation of bus voltage at the time of load mutation, voltage secondary control is added to realize dynamic adjustment of DC bus voltage fluctuation. The proposed method can achieve balance and stable operation of energy storage units. The simulation results verified the effectiveness and stability of the proposed control strategy.
Źródło:
Archives of Electrical Engineering; 2018, 67, 4; 885-898
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Toluene Mono-nitration in a Semi-batch Reactor
Autorzy:
Chen, L. P.
Chen, W. P.
Liu, Y.
Peng, J. H.
Liu, R. H.
Powiązania:
https://bibliotekanauki.pl/articles/358853.pdf
Data publikacji:
2008
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
toluene mono-nitration
apparent activation energy
semi-batch reaction
thermal hazard
Opis:
Toluene mono-nitration in a semi-batch reactor was investigated with reaction calorimeter (RC1). The mixed acid HNO3/H2SO4/H2O (wt%) was used in proportion 13/66/21, which is similar to industrial parameters. The exothermic rates at different reaction temperatures were compared, and then the curves of heat generation rate after dosing were analyzed. The Maximal Temperature attainable by runaway of the desired Synthetic Reaction (MTSR) under different conditions were calculated for the course hazard evaluation. The results showed that the average reaction heat of mono-nitration was between 169.07~177.11 kJ mol-1, and the special heat of reactant was about 2 kJ kg-1 K-1. Average Ea of second order kinetic was about 30 kJ mol-1, and reaction rate was 10-4 mol s-1 l-1 order of magnitude when the strength of sulphuric acid was about 73.5%. It was also found that when temperature or stirring speed increases, the potential heat accumulation decreases.
Źródło:
Central European Journal of Energetic Materials; 2008, 5, 2; 37-47
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Semi-analytical solution of optimization on moon-pool shaped WEC
Autorzy:
Zhang, W. C.
Liu, H. X.
Zhang, X. W.
Zhang, L.
Powiązania:
https://bibliotekanauki.pl/articles/963397.pdf
Data publikacji:
2016
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
wave energy
eigenfunction expansion
moon pool
conversion ability
optimization
Opis:
In order to effectively extract and maximize the energy from ocean waves, a new kind of oscillating-body WEC (wave energy converter) with moon pool has been put forward. The main emphasis in this paper is placed on inserting the damping into the equation of heaving motion applied for a complex wave energy converter and expressions for velocity potential added mass, damping coefficients associated with exciting forces were derived by using eigenfunction expansion matching method. By using surface-wave hydrodynamics, the exact theoretical conditions were solved to allow the maximum energy to be absorbed from regular waves. To optimize the ability of the wave energy conversion, oscillating system models under different radius-ratios are calculated and comparatively analyzed. Numerical calculations indicated that the capture width reaches the maximum in the vicinity of the natural frequency and the new kind of oscillating-body WEC has a positive ability of wave energy conversion.
Źródło:
Polish Maritime Research; 2016, S 1; 25-31
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of root system architecture affected by swarming behavior
Autorzy:
Li, S.
Yu, W.
Liu, X.
Wang, M.
Powiązania:
https://bibliotekanauki.pl/articles/1078927.pdf
Data publikacji:
2020
Wydawca:
Instytut Ogrodnictwa
Tematy:
root system architecture
soil nutrient
interaction
root system
root growth
dynamic growth
swarming
behaviour
Opis:
The root system architecture (RSA) displays complex morphological characteristics because of diverse root growth behaviors. Recent studies have revealed that swarming behavior among roots is particularly important for RSA to adapt to environmental stimuli. However, few models are proposed to simulate RSA based on swarming behavior of roots. To analyze plasticity of RSA affected by swarming behavior, we propose viewing it as a swarm of single roots. A swarming behavior model is proposed by considering repulsion, alignment, and preference of individual single roots. Then, the swarming behavior model is integrated into a simple and generic RSA model (called ArchiSimple). Lastly, characteristics of RSA affected by swarming behavior model and non-swarming behavior model are compared and analyzed under three different virtual soil sets. The characteristics of RSA (such as primary root length, lateral root length, lateral roots, and resource uptake) are significantly promoted by swarming behavior. Root system distributions can also be greatly affected by swarming behavior. These results show that root foraging and exploration in soil can be regarded as collective behavior of individual single root.
Źródło:
Journal of Horticultural Research; 2020, 28, 1; 1-12
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł

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