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Tytuł:
A novel multiple attribute decision-making method based on Schweizer-Sklar t-norm and t-conorm with q-rung dual hesitant fuzzy information
Autorzy:
Xu, Yuan
Wang, Jun
Powiązania:
https://bibliotekanauki.pl/articles/2106503.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
multiple attribute decision-making
Schweizer-Sklar t-norm and t-conorm
q-rung dual hesitant fuzzy Schweizer-Sklar Hamy mean operator
q-rung dual hesitant fuzzy Schweizer-Sklar weighted Hamy mean operator
Opis:
The recently proposed q-rung dual hesitant fuzzy sets (q-RDHFSs) not only deal with decision makers’ (DMs’) hesitancy and uncertainty when evaluating the performance of alternatives, but also give them great liberty to express their assessment information comprehensively. This paper aims to propose a new multiple attribute decision-making (MADM) method where DMs’ evaluative values are in form of q-rung dual hesitant fuzzy elements (q-RDHFEs). Firstly, we extend the powerful Schweizer-Sklar q-norm and t-conorm (SSTT) to q-RDHFSs and propose novel operational rules of q-RDHFEs. The prominent advantage of the proposed operations is that they have important parameters q and r, making the information fusion procedure more flexible. Secondly, to effectively cope with the interrelationship among attributes, we extend the Hamy mean (HM) to q-RDHFSs and based on the newly developed operations, we propose the q-rung dual hesitant fuzzy Schweizer-Sklar Hamy mean (q-RDHFSSHM) operator, and the q-rung dual hesitant fuzzy Schweizer-Sklar weighted Hamy mean (q-RDHFSSWHM) operator. The properties of the proposed operators, such as idempotency, boundedness and monotonicity are discussed in detail. Third, we propose a new MADM method based on the q-RDHFSSWHM operator and give the main steps of the algorithm. Finally, the effectiveness, flexibility and advantages of the proposed method are discussed through numerical examples.
Źródło:
Archives of Control Sciences; 2022, 32, 1; 175--228
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanism of the combined effects of air rate and froth depth on entrainment factor in copper flotation
Autorzy:
Wang, Lei
Xing, Yaowen
Wang, Jun
Powiązania:
https://bibliotekanauki.pl/articles/1449999.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
froth flotation
copper
entrainment
air rate
froth depth
Opis:
The effect of air rate and froth depth on the entrainment factor in flotation has been extensively studied, but further investigation on the underlying mechanism for their effect is still required. In this study, flotation tests were performed at different air rates and froth depths in a 3 $dm^3$ continuously operated cell using an artificial copper ore. The results showed that entrainment factor was affected by both air rate and froth depth, and the combined effect of these variables on entrainment factor depended strongly on the particle size. The entrainment factor increased with either increasing air rate at a relatively shallow froth or decreasing froth depth at a relatively high air rate. At a very low air rate and deep froth, higher entrainment factor was observed for mid-size and coarse particles. When the entrainment factor was correlated to the effective liquid velocity at the pulp/froth interface, the results indicated that multiple mechanisms were responsible for the effect on entrainment factor. At a relatively high air rate and shallow froth depth, entrainment factor had a linear relationship with the interface effective liquid velocity, suggesting that drag force dominated the change in the entrainment factor when air rate and froth depth were varied. At a very low air rate and deep froth, the entrainment factor for fine particles was found to correlate strongly with the interface effective liquid velocity, while the entrapment of solid particles may be the main reason for the high entrainment factor for mid-size and coarse particles under this condition.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 1; 43-53
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multi-attribute decision-making based on q-rung dual hesitant power dual Maclaurin symmetric mean operator and a new ranking method
Autorzy:
Li, Li
Wang, Jun
Ji, Chunliang
Powiązania:
https://bibliotekanauki.pl/articles/2175106.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
q-rung dual hesitant fuzzy sets
power geometric
dual Maclaurin symmetric mean
power dual Maclaurin symmetric mean
multi-attribute decision-making
Opis:
The ability of q-rung dual hesitant fuzzy sets (q-RDHFSs) in dealing with decision makers’ fuzzy evaluation information has received much attention. This main aim of this paper is to propose new aggregation operators of q-rung dual hesitant fuzzy elements and employ them in multi-attribute decision making (MADM). In order to do this, we first propose the power dual Maclaurin symmetric mean (PDMSM) operator by integrating the power geometric (PG) operator and the dual Maclaurin symmetric mean (DMSM). The PG operator can reduce or eliminate the negative influence of decision makers’ extreme evaluation values, making the final decision results more reasonable. The DMSM captures the interrelationship among multiple attributes. The PDMSM takes the advantages of both PG and DMSM and hence it is suitable and powerful to fuse decision information. Further, we extend the PDMSM operator to q-RDHFSs and propose q-rung dual hesitant fuzzy PDMSM operator and its weighted form. Properties of these operators are investigated. Afterwards, a new MADM method under q-RDHFSs is proposed on the basis on the new operators. Finally, the effectiveness of the new method is testified through numerical examples.
Źródło:
Archives of Control Sciences; 2022, 32, 3; 627--658
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Environmental Quality, Corruption and Industry Growth: The Global Perspective
Jakość środowiska, korupcja i rozwój przemysłu: perspektywa globalna
Autorzy:
Cui, Min
Wang, Jun-Sheng
Chang, Chun-Ping
Powiązania:
https://bibliotekanauki.pl/articles/1840985.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Komitet Człowiek i Środowisko PAN
Tematy:
environmental quality
corruption
industry growth
panel cointegration
causality
jakość środowiska
korupcja
wzrost gospodarczy
kointegracja panelowa
przyczynowość
Opis:
This paper investigates the causal relationship between environmental quality and corruption for 129 countries, using the panel cointegration and panel-based error correction models for the period 2002-2015. In the paper, we use EPI, EHI, and EVI to represent environmental quality, which are more reasonable and comprehensive. We further take industry growth into consideration and investigate its impact on environmental quality. Our results corroborate that there exists a long-term equilibrium cointegrated relationship among the variables, both of corruption and industry growth have a negative effect on environmental quality and the corruption can seriously decrease environmental quality in the long term, while industry growth weakens environmental quality no matter in the short or long run.
W artykule zbadano związek przyczynowy między jakością środowiska a korupcją w 129 krajach, wykorzystując modele kointegracji panelowej i panelowej korekcji błędów za lata 2002-2015. W pracy używamy EPI, EHI i EVI do wyznaczania jakości środowiska, które wydają się najbardziej sensowne i wszechstronne. Ponadto bierzemy pod uwagę rozwój branży i badamy jego wpływ na jakość środowiska. Nasze wyniki potwierdzają, że istnieje długoterminowa stabilna skointegorowana relacja pomiędzy zmiennymi, zarówno korupcja, jak i rozwój przemysłu mają negatywny wpływ na jakość środowiska, a korupcja może poważnie obniżyć jakość środowiska w dłuższej perspektywie, podczas gdy wzrost przemysłu osłabia jakość środowiska zarówno w krótkim, jak i długim okresie.
Źródło:
Problemy Ekorozwoju; 2021, 16, 1; 29-37
1895-6912
Pojawia się w:
Problemy Ekorozwoju
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel multiple attribute decision making method based on q-rung dual hesitant uncertain linguistic sets and Muirhead mean
Autorzy:
Wang, Jun
Shang, Xiaopu
Feng, Xue
Sun, Mengyang
Powiązania:
https://bibliotekanauki.pl/articles/229622.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
q-rung dual hesitant uncertain linguistic sets
Muirhead mean
q-rung dual hesitant uncertain linguistic Muirhead mean
multi-attribute decision making
informatization level evaluation
Opis:
This paper aims to propose a new multi-attribute decision making (MADM) method in complicated and fuzzy decision-making environment. To express both decision makers (DMs’) quantitative and qualitative evaluation information comprehensively and consider their high hesitancy in giving their assessment values in MADM process, we combine q-rung dual hesitant fuzzy sets (q-RDHFSs) with uncertain linguistic variables and develop a new tool, called the q-rung dual hesitant uncertain linguistic sets (q-RDHULSs). First, the definition, operations and comparison method of q-RDHULSs are proposed. Second, given the interrelationship among multiple q-rung dual hesitant uncertain linguistic variables (q-RDHULVs) we introduce some aggregation operators (AOs) to fuse q-rung dual hesitant uncertain linguistic (q-RDHUL) information based on the Muirhead mean, i.e. the q-RDHUL Muirhead mean operator, the q-RDHUL weighted Muirhead mean operator, the q-RDHUL dual Muirhead mean operator, and the q-RDHUL weighted dual Muirhead mean operator. To cope with MADM problems with q-RDHUL information, we propose a new method based on the proposed AOs. Afterwards, we apply the proposed method to an enterprise informatization level evaluation problem to verify its effectiveness. In addition, we also explain why our proposed method is more powerful and flexible than others.
Źródło:
Archives of Control Sciences; 2020, 30, 2; 233-272
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Local uniform rotundity in Musielak-Orlicz sequence space equipped with the Luxemburg norm
Autorzy:
Wang, Jun Ming
Liu, Xin Bo
Cui, Yun An
Powiązania:
https://bibliotekanauki.pl/articles/746220.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
local uniform rotundity
weak local uniform rotundity
Musielak-Orlicz sequence space
Luxemburg norm
Opis:
In this paper, we present criteria for local uniform rotundity and weak local uniform rotundity in Musielak-Orlicz sequence spaces equipped with the Luxemburg norm.
Źródło:
Commentationes Mathematicae; 2006, 46, 1
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation of the Effect of Geometric Parameters of the Fibre Transport Channel in Open-End Rotor Spinning
Symulacja wpływu parametrów geometrycznych kanału transportu włókien w procesach przędzenia bezwrzecionowego i rotorowego
Autorzy:
Lin, Huiting
Akankwasa, Nicholus Tayari
Wang, Jun
Zhang, Chuyang
Powiązania:
https://bibliotekanauki.pl/articles/233463.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
fibre transport channel
airflow
simulation
rotor spinning
bypass channel
kanał transportowy włókien
przepływ powietrza
symulacja
wirowanie
kanał obejściowy
Opis:
The airflow field in a fibre transport channel is crucial as it affects the fibre configuration significantly and, consequently, the yarn properties. Geometric parameters are found to be critical in influencing airflow characteristics. 3D finite volume computationswere adopted to evaluate the effects of geometric parameters of the transport channel on airflow characteristics. A bypass channel for extra air supply into the transport channel was also evaluated. The results reveal that the transport channel inlet area has a more significant impact on the vortices generated at the channel inlet than the transport channel length. Either increasing the transport channel length or decreasing the transport inlet area can reduce the vortices but cannot eliminate them. By adopting a bypass channel, the vortices are reduced significantly and the air velocity at the transport channel inlet, especially in the fibre separation area, is increased.
Pole przepływu powietrza w kanale transportującym włókna ma kluczowe znaczenie, ponieważ wpływa znacząco na konfigurację włókien, a w konsekwencji na właściwości przędzy. Stwierdzono, że parametry geometryczne mają krytyczne znaczenie dla wpływu na charakterystykę przepływu powietrza. Obliczenia objętości 3D zostały przyjęte w celu oceny wpływu parametrów geometrycznych kanału transportowego na charakterystykę przepływu powietrza. Oceniono także kanał obejściowy dla dodatkowego dopływu powietrza do kanału transportowego. Wyniki pokazały, że obszar wlotowy kanału transportowego ma bardziej znaczący wpływ na wiry generowane na wlocie kanału niż długość kanału transportowego. Zwiększenie długości kanału transportowego lub zmniejszenie obszaru wlotu transportowego może zmniejszyć wiry, ale nie może ich wyeliminować. Przyjmując kanał obejściowy, wiry są znacznie zmniejszone, a prędkość powietrza na wlocie kanału transportowego, zwłaszcza w obszarze oddzielania włókien, jest zwiększona.
Źródło:
Fibres & Textiles in Eastern Europe; 2019, 2 (134); 52-57
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Local Characterisation and Detection of Woven Fabric Texture Based on a Sparse Dictionary
Autorzy:
Wu, Ying
Wang, Ren
Lou, Lin
Wang, Lali
Wang, Jun
Powiązania:
https://bibliotekanauki.pl/articles/2172000.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
fabric texture representation
sparse representation
weave repeat
defect detection
dictionary learning
Opis:
To achieve enhanced accuracy of fabric representation and defect detection, an innovative approach using a sparse dictionary with small patches was used for fabric texture characterisation. The effectiveness of the algorithm proposed was tested through comprehensive characterisation by studying eight weave patterns: plain, twill, weft satin, warp satin, basket, honeycomb, compound twill, and diamond twill and detecting fabric defects. Firstly, the main parameters such as dictionary size, patch size, and cardinality T were optimised, and then 40 defect-free fabric samples were characterised by the algorithm proposed. Subsequently, the Impact of the weave pattern was investigated based on the representation result and texture structure. Finally, defective fabrics were detected. The algorithm proposed is an alternative simple and scalable method to characterise fabric texture and detect textile defects in a single step without extracting features or prior information.
Źródło:
Fibres & Textiles in Eastern Europe; 2022, 3 (151); 33--40
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microphytoplankton communities off the Antarctic Peninsula region in austral summer 2010/2011
Autorzy:
Luan, Qingshan
Wang, Chenghua
Wang, Xinliang
Sun, Jianqiang
Niu, Mingxiang
Wang, Jun
Powiązania:
https://bibliotekanauki.pl/articles/2051373.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Źródło:
Polish Polar Research; 2013, 4; 413-428
0138-0338
2081-8262
Pojawia się w:
Polish Polar Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of the Mechanical and Thermal Properties, and Impact Sensitivity of Pressed HMX-based PBX
Autorzy:
Li, Yuxiang
Wu, Peng
Hua, Cheng
Wang, Jun
Huang, Bing
Chen, Jin
Qiao, Zhiqiang
Yang, Guangcheng
Powiązania:
https://bibliotekanauki.pl/articles/358006.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
nanoexplosives
impact sensitivity
particle size
hot spot
Opis:
Submicron- and nano-explosives have attracted growing attention, while the mechanism of how particle size influences the impact sensitivity is not completely understood. In the present work, HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) based PBXs (plastic bonded explosives) of three particle size distributions (1-2 and 10-20 μm, and 100-300 nm) and two pressed densities (91%TMD and 79%TMD) were characterized and tested with a range of techniques to determine their mechanical and thermal properties and impact sensitivities. The results demonstrated that with decreased particle size, the mechanical strength as well as the thermal conductivity were dramatically improved, and the impact sensitivity was significant decreased. The structure of impacted samples suggested that the ignition mechanism is dependant on the particle size. Samples with higher density were more sensitive to impact, as the impact force acting on these samples was higher. The correlation between particle size and impact sensitivity is discussed in detail.
Źródło:
Central European Journal of Energetic Materials; 2019, 16, 2; 295-315
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heuristic energy-saving virtual network embedding algorithm based on Katz centrality
Autorzy:
Zhu, Qiang
Wang, Qing-Jun
Zang, Mu-Jun
Wang, Zhen-Dong
Xiao, Chang
Powiązania:
https://bibliotekanauki.pl/articles/141679.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
energy-saving virtual network
integer linear programming
Katz centrality
network virtualization embedding
virtualization
Opis:
Current networks are designed for peak loads leading to low utilization of power resources. In order to solve this problem, a heuristic energy-saving virtual network embedding algorithm based on the Katz centrality (Katz-VNE) is proposed. For solving an energy-saving virtual network embedding problem, we introduce the Katz centrality to represent the node influence. In order to minimize the energy consumption of the substrate network, the energy-saving virtual network embedding problem is formulated as an integer linear program, and the Katz-VNE is used to solve this problem. The Katz-VNE tries to embed the virtual nodes onto the substrate nodes with high Katz centrality, which is effective, and uses the shortest paths offering the best factor of bandwidths to avoid the hot nodes. The simulation results demonstrate that the long-term average energy consumption of the substrate network is reduced significantly, and the long-term revenue/cost ratio, the acceptance rate of virtual network requests, and the hibernation rate of substrate nodes as well as links are improved significantly.
Źródło:
Archives of Electrical Engineering; 2020, 69, 3; 595-608
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of flocculation performance and mechanism of ultrafine montmorillonite particles with NPAM
Autorzy:
Wang, Lujun
Min, Fanfei
Chen, Jun
Wang, Ting
Zhou, Zhuang
Powiązania:
https://bibliotekanauki.pl/articles/2146901.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
montmorillonite
flocculant
nonionic polyacrylamide
density functional theory
Opis:
Ultrafine montmorillonite particles are the main clay minerals in industrial wastewater. In order to explore the flocculation performance and mechanism of flocculant with montmorillonite, the effects of nonionic polyacrylamide (NPAM) dosage and molecular weight on flocculation effect were studied using a flocculation sedimentation experiment. The morphology of flocs was observed by metallographic microscope and scanning electron microscope, and the microscopic adsorption mechanism was studied utilizing density functional theory (DFT). The results show that the best reagent system for the montmorillonite sample is that the molecular weight of NPAM is 14 million and the added amount is 100 g/t. The floc size increases with rising NPAM dosage, forming a unique multi-level compact space network structure through polymer bridging. The adsorption energy of acrylamide on the Na-(001) surface of montmorillonite is -108.81 kJ/mol, which is significantly higher than -50.66 kJ/mol on the None-(001) surface. Hydrogen bonding is not the main reason for the adsorption of acrylamide on the montmorillonite surface. NPAM mainly causes the flocculation and sedimentation of montmorillonite through the processes of polymer bridging and electrostatic attraction. This study can provide a theoretical basis for the design and synthesis of new flocculants.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 3; art. no. 147790
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the second largest eigenvalue of a mixed graph
Autorzy:
Zhou, Jun
Fan, Yi-Zheng
Wang, Yi
Powiązania:
https://bibliotekanauki.pl/articles/743812.pdf
Data publikacji:
2007
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
mixed graph
Laplacian eigenvalue
degree
Opis:
Let G be a mixed graph. We discuss the relation between the second largest eigenvalue λ₂(G) and the second largest degree d₂(G), and present a sufficient condition for λ₂(G) ≥ d₂(G).
Źródło:
Discussiones Mathematicae Graph Theory; 2007, 27, 2; 373-384
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New Jurassic tettigarctid cicadas from China with a novel example of disruptive coloration
Autorzy:
CHEN, JUN
ZHANG, HAICHUN
WANG, BO
ZHENG, YAN
WANG, XIAOLI
ZHENG, XIAOTING
Powiązania:
https://bibliotekanauki.pl/articles/945441.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
insecta
hemiptera
tettigarctidae
coloration pattern
jurassic
china
daohugou
Opis:
Tettigarctidae is the most primitive family of Cicadoidea, with only two relict species. Although they are relatively well known from Eurasia, Australia, Africa, and South America, their Mesozoic examples are typically preserved only as isolated forewings. Herein, a new genus Sanmai Chen, Zhang, and B. Wang with three new species (Sanmai kongi Chen, Zhang, and B. Wang, S. mengi Chen, Zhang, and B. Wang, and S. xuni Chen, Zhang, and B. Wang) are described based on fossil specimens from the Middle–Upper Jurassic of northeastern China, with well-preserved body structures, forewing and hindwing venations, making it the hitherto best known extinct tettigarctid taxon. The new genus, provisionally assigned to the tribe Turutanoviini, provides some new information about the evolution and palaeobiogeography of Mesozoic Tettigarctidae. The genus Paraprosbole is synonymized with Shuraboprosbole. In addition, the coloration pattern of forewing, prominent on some specimens of Sanmai kongi Chen, Zhang, and B. Wang sp. nov. and Sanmai xuni Chen, Zhang, and B. Wang sp. nov., represents a novel example of disruptive coloration in Tettigarctidae, which can effectively break up the body outline as well as surface, and so likely enabled these cicadas to reduce the detectability of potential predators.
Źródło:
Acta Palaeontologica Polonica; 2016, 61, 4; 853-862
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessing system impedance based on data regrouping
Autorzy:
Xu, Shuangting
Xiao, Xianyong
Wang, Yang
Wu, Jun
Powiązania:
https://bibliotekanauki.pl/articles/1848965.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
system impedance
passive method
Thevenin equivalent
power system
Opis:
In recent years, assessing supply system impedance has become crucial due to the concerns on power quality and the proliferation of distributed generators. In this paper, a novel method is shown for passive measurement of system impedances using the gapless waveform data collected by a portable power quality monitoring device. This method improves the overall measurement accuracy through data regrouping. Compared with the traditional methods that use the consecutive measurement data directly, the proposed method regroups the data to find better candidates with less flotation on the system side. Simulation studies and extensive field tests have been conducted to verify the effectiveness of the proposed method. The results indicate that the proposed method can serve as a useful tool for impedance measurement tasks performed by utility companies.
Źródło:
Metrology and Measurement Systems; 2021, 28, 1; 191-208
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessing system impedance based on data regrouping
Autorzy:
Xu, Shuangting
Xiao, Xianyong
Wang, Yang
Wu, Jun
Powiązania:
https://bibliotekanauki.pl/articles/1848954.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
system impedance
passive method
Thevenin equivalent
power system
Opis:
In recent years, assessing supply system impedance has become crucial due to the concerns on power quality and the proliferation of distributed generators. In this paper, a novel method is shown for passive measurement of system impedances using the gapless waveform data collected by a portable power quality monitoring device. This method improves the overall measurement accuracy through data regrouping. Compared with the traditional methods that use the consecutive measurement data directly, the proposed method regroups the data to find better candidates with less flotation on the system side. Simulation studies and extensive field tests have been conducted to verify the effectiveness of the proposed method. The results indicate that the proposed method can serve as a useful tool for impedance measurement tasks performed by utility companies.
Źródło:
Metrology and Measurement Systems; 2021, 28, 1; 191-208
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The feasibility of using high-resolution ultrasonography to assess ulnar nerve in patients with diabetes mellitus
Przydatność ultrasonografii wysokiej rozdzielczości w badaniu nerwu łokciowego u pacjentów chorujących na cukrzycę
Autorzy:
Chen, Jun
Wang, Chun-Lei
Wu, Shan
He, Shan
Ren, Jun
Powiązania:
https://bibliotekanauki.pl/articles/1033382.pdf
Data publikacji:
2017
Wydawca:
Medical Communications
Tematy:
high-resolution ultrasonography
Opis:
Objective: The aim of this study was to investigate the usefulness of high-resolution ultrasonography for the diagnosis of polyneuropathy in diabetes mellitus patients by the examination of the ulnar nerves. Method: We recruited 100 healthy age-matched volunteers (50 women and 50 men) with 200 arms without diabetes or cubital tunnel syndrome as the control group. We assessed the upper limbs of 100 diabetes mellitus patients (45 women and 55 men), 40 of whom had electrophysiologically confirmed diabetic peripheral neuropathy and 60 had no diabetic peripheral neuropathy in the upper limbs. Age, sex, height and weight were recorded and the cross-sectional area of the ulnar nerve was measured at every predetermined site. Results: The cross-sectional area of the ulnar nerve was measured at six sites (mid-humerus, inlet of the cubital tunnel, outlet of the cubital tunnel, upon the medial epicondyle, 6 cm upon the wrist crease and Guyon tunnel). The ulnar nerve in two measuring sites (mid-humerus, upon the medial epicondyle) in the control group showed a statistical difference between men and women (p < 0.05). There was no statistical difference in the cross-sectional area in the control group when dominant and non-dominant arms were compared. The cross-sectional area was larger in the diabetic peripheral neuropathy group in three sites (inlet of the cubital tunnel, outlet of the cubital tunnel, Guyon tunnel) compared with those in the control group. Conclusion: High-resolution ultrasonography may be helpful in the early diagnosis of peripheral neuropathy in diabetic patients.
Cel: Celem badania było określenie przydatności ultrasonografii wysokiej rozdzielczości w diagnostyce polineuropatii u pacjentów z cukrzycą poprzez badanie nerwu łokciowego. Metoda: Przebadano kończyny górne 100 pacjentów z cukrzycą (45 kobiet i 55 mężczyzn), z których 40 cierpiało na elektrofizjologicznie potwierdzoną obwodową neuropatię cukrzycową, a u 60 nie rozpoznano obwodowej neuropatii cukrzycowej w kończynach górnych. Jako grupa kontrolna w badaniu udział wzięło 100 zdrowych wolontariuszy w podobnym wieku (50 kobiet i 50 mężczyzn), niecierpiących na cukrzycę ani zespół kanału łokciowego (łącznie 200 rąk). Określono wiek, płeć, wzrost i wagę oraz zmierzono pole przekroju poprzecznego nerwu łokciowego w każdym ustalonym miejscu. Wyniki: Pole przekroju poprzecznego nerwu łokciowego zmierzono w sześciu miejscach (środek kości ramiennej, wejście do kanału łokciowego, wyjście z kanału łokciowego, nad nadkłykciem przyśrodkowym, 6 cm ponad nadgarstkiem i kanał Guyona). W grupie kontrolnej wykazano statystycznie istotną różnicę w nerwie łokciowym w dwóch miejscach pomiaru (środek kości ramiennej, nad nadkłykciem przyśrodkowym) pomiędzy mężczyznami a kobietami (p < 0,05). Nie wykazano różnicy statystycznej w polu przekroju poprzecznego w grupie kontrolnej podczas porównywania ręki dominującej i niedominującej. Pole przekroju poprzecznego było większe w grupie z obwodową neuropatią cukrzycową w trzech miejscach (wejście do kanału łokciowego, wyjście z kanału łokciowego, kanał Guyona) w porównaniu z grupą kontrolną. Wniosek: Ultrasonografia wysokiej rozdzielczości może okazać się pomocna we wczesnej diagnostyce neuropatii obwodowej u pacjentów z cukrzycą. Artykuł w wersji polskojęzycznej jest dostępny na stronie http://jultrason.pl/index.php/wydawnictwa/volume-17-no-70
Źródło:
Journal of Ultrasonography; 2017, 17, 70; 160-166
2451-070X
Pojawia się w:
Journal of Ultrasonography
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stepper motor open-loop control system modeling and control strategy optimization
Autorzy:
Zhang, Deode
Wang, Jingqi
Qian, Lei
Yi, Jun
Powiązania:
https://bibliotekanauki.pl/articles/141113.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
acceleration and deceleration control
open loop control
stepper motor
subdivision control
system modeling
Opis:
The study of the subdivision driving technology of a stepper motor and two types of typical acceleration and deceleration curves aims at optimizing the open-loop control performance of the stepper motor. The simulation model of a two-phase hybrid stepper motor open-loop control system is set up based on the mathematical model of the stepper motor, in order to let the stepper motor have the smaller stepper angle, two types of typical acceleration and a deceleration curve algorithm are designed for the real- time online calculation based on the subdivision driving technology. It respectively carries out the simulation analysis for their control effects. The simulation results show that the parabolic acceleration and deceleration curves have a larger maximum in-step rotation angle and the faster dynamic response ability in the same control period, and at the same time, the position tracking error of an intermediate process is smaller.
Źródło:
Archives of Electrical Engineering; 2019, 68, 1; 63-75
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polarization dependence of stimulated Brillouin scattering-based switchable microwave photonic filter
Autorzy:
Gu, Jun
Wang, Fei
Lu, Youxi
Peng, Mengmeng
Shi, Lun
Kang, Wen
Huang, Jingxin
Powiązania:
https://bibliotekanauki.pl/articles/173837.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
microwave photonic filter
stimulated Brillouin scattering
polarization dependence
Opis:
We propose and experimentally demonstrate a switchable microwave photonic filter based on polarization dependence of stimulated Brillouin scattering (SBS). The continuous optical wave from a tunable laser source is split into two branches. One branch serves as the SBS pump source and another branch serves as the signal source which are interactional to generate the SBS effect in the dispersion-shifted fiber. Only by adjusting the polarization direction of pump light and signal light, a frequency response switched between bandpass and notch filtering shape can be obtained.
Źródło:
Optica Applicata; 2019, 49, 1; 5-11
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oxidative stress and apotosis to zebrafish (Danio rerio) embryos exposed to perfluorooctane sulfonate (PFOS) and ZnO nanoparticles
Autorzy:
Du, Jia
Cai, Jun
Wang, Shutao
You, Hong
Powiązania:
https://bibliotekanauki.pl/articles/2161865.pdf
Data publikacji:
2017-03-30
Wydawca:
Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:
ZnO nanoparticles
perfluorooctane sulfonate
PFOS
zebrafish
Oxidative stress
Apoptosis
Opis:
Objectives Perfluorooctane sulfonate (PFOS) and zinc oxide nanoparticles (ZnO-NPs) are frequently detected in the environment but few studies have assessed the joint toxicity of them. Oxidative stress and apoptosis to zebrafish (Danio rerio) embryos induced by the PFOS and ZnO-NPs were investigated in this study. Material and Methods The embryos were exposed to the PFOS (0, 0.4, 0.8 and 1.6 mg/l), ZnO-NPs (12.5, 25, 50 mg/l) and PFOS plus ZnO-NPs (0.4+12.5, 0.8+25 and 1.6+50 mg/l) mixture solutions until 96 h post-fertilization. Activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (Gpx) and malondialdehyde (MDA) content were measured in zebrafish embryos after exposure lasting for 96 h. At the same time, the genes expression related to reactive oxygen species (ROS) generation, oxidative damage and apoptosis were also measured. Results A significant induction of the ROS accompanied by the increase in the activity of the Gpx and MDA contents were found in co-treatment groups. Furthermore, several apoptosis pathway related genes such as Bax, p53, caspase-3 and caspase-9 were significantly up-regulated in the PFOS plus ZnO-NPs exposure groups, while anti-apoptotic gene Bcl-2 was significantly down-regulated in the PFOS plus ZnO-NPs exposure groups. In addition, some oxidative stress-related genes such as Cat, GSH peroxidase 1 (Gpx1a) and superoxide dismutase 1 (Sod1) were also significantly down-regulated after the PFOS plus ZnO-NPs co-treatments. Conclusions The results demonstrated that the PFOS plus ZnO-NPs co-exposure could cause more serious oxidative stress and apoptosis than the PFOS and ZnO-NPs exposure alone at the exposure concentrations above. The synergistic effects of the PFOS and ZnO-NPs may be the important mechanisms of their toxicity to zebrafish embryos. Int J Occup Med Environ Health 2017;30(2):213–229
Źródło:
International Journal of Occupational Medicine and Environmental Health; 2017, 30, 2; 213-229
1232-1087
1896-494X
Pojawia się w:
International Journal of Occupational Medicine and Environmental Health
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of methods for correcting outliers in ECG-based biometric identification
Autorzy:
Jun, Su
Szmajda, Miroslaw
Khoma, Volodymyr
Khoma, Yuriy
Sabodashko, Dmytro
Kochan, Orest
Wang, Jinfei
Powiązania:
https://bibliotekanauki.pl/articles/221531.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Euclidean distance
autoencoders
outlier correction
ECG signal
human identification
biometrics
Opis:
The aim of this paper is to compare the efficiency of various outlier correction methods for ECG signal processing in biometric applications. The main idea is to correct anomalies in various segments of ECG waveform rather than skipping a corrupted ECG heartbeat in order to achieve better statistics. Experiments were performed using a self-collected Lviv Biometric Dataset. This database contains over 1400 records for 95 unique persons. The baseline identification accuracy without any correction is around 86%. After applying the outlier correction the results were improved up to 98% for autoencoder based algorithms and up to 97.1% for sliding Euclidean window. Adding outlier correction stage in the biometric identification process results in increased processing time (up to 20%), however, it is not critical in the most use-cases.
Źródło:
Metrology and Measurement Systems; 2020, 27, 3; 387-398
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Crystal Structure and Thermal Behaviour of Imidazolium 2,4,5-Trinitroimidazolate
Autorzy:
Jian, Chen
Pengbao, Lian
Lizhen, Chen
Jianlong, Wang
Jun, Chen
Powiązania:
https://bibliotekanauki.pl/articles/357998.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
imidazolium 2,4,5-trinitroimidazolate
crystal structure
thermal decomposition
TG-DSC
model-free methods
Opis:
In this work, imidazolium 2,4,5-trinitroimidazolate was obtained from 2,4,5-tri-iodoimidazole in a yield of 48%. Single-crystal X-ray diffraction analysis showed that this compound belongs to the triclinic crystal system with space group P-1. Thermogravimetric-differential scanning calorimetry (TG-DSC) was performed under a nitrogen atmosphere at heating rates of 5, 10, 15 and 20 °C·min−1. Compound 3 clearly exhibits an exothermic decomposition. The activation energy (E) and pre-exponential factor (lnA) calculated by the Kissinger method were 113.67 kJ·mol−1 and 25.30 s−1, respectively. The E values obtained by the FWO and KAS methods changed slightly from 103.33 to 113.69 kJ·mol−1 and from 101.52 to 111.97 kJ·mol−1, respectively, which makes us believe that its thermal decomposition can be described using only one reaction model. The Šatava-Šesták method and the compensation effect were used to study the thermal decomposition mechanism of imidazolium 2,4,5-trinitroimidazolate. [Formula] is regarded as the most appropriate thermal decomposition kinetic equation. The impact sensitivity, friction sensitivity, detonation velocity and explosion pressure of imidazolium 2,4,5-trinitroimidazolate were 43 cm, 46%, 7056.9 m·s−1 and 1.9703 · 1010 Pa (ρ = 1.538 g·cm−3), respectively. Imidazolium 2,4,5-trinitroimidazolate is incompatible with RDX, HMX, TKX-50 and CL-20.
Źródło:
Central European Journal of Energetic Materials; 2019, 16, 4; 547-563
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
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:
Theoretical Simulations on Physicochemical Performance of Novel High-energy BHDBT-based Propellants
Autorzy:
Wang, Ke
Huang, Hai-tao
Xu, Hui-xiang
Li, Huan
Li, Jun-qiang
Fan, Xue-zhong
Pang, Wei-qiang
Powiązania:
https://bibliotekanauki.pl/articles/27787879.pdf
Data publikacji:
2021
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
molecular dynamic
BHDBT
migration
mechanical properties
safety
Opis:
Based on Energy Calculation Star program and molecular dynamic method, three designed 2,3-bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol tetranitrate-based (BHDBT) propellants are firstly reported and their physicochemical performance are investigated. Results suggest that compared with HMX-based and CL-20-based propellants, the specific impulses of all BHDBT-based propellants surpass or approximate 280 s, which indicates the latter have the potential to be high-energy propellants. The diffusion coefficient of plasticizers in BHDBT-based propellant decrease as the temperature reduces, and reduce in the order: Bu-NENA > TMETN > BTTN. The densities of all BHDBT-based propellants surpass or approximate 1.7 g/cm3. The comparison of elastic constants, Poisson’s ratios and K/G values indicates that the mechanical properties of three BHDBT-based propellants increase in the order (by plasticizer): Bu-NENA < TMETN < BTTN. The bond length analysis of C–NO2 and O–NO2 bond in BHDBT suggests that the former is the trigger bond in the BHDBT-based propellants, and the safety of BHDBT-based propellants and BHDBT crystal decreases in the order: GAP/BTTN/Al/BHDBT > GAP/Bu-NENA/Al/BHDBT ≈ GAP/TMETN/Al/BHDBT > BHDBT. In conclusion, GAP/BTTN/Al/BHDBT propellant has the potential to be a novel high-energy propellant.
Źródło:
Central European Journal of Energetic Materials; 2021, 18, 1; 5--24
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photonic generation of broadly tunable radio-frequency signal using a reflective semiconductor optical amplifier
Autorzy:
Lu, Youxi
Wang, Fei
Gu, Jun
Shi, Lun
Peng, Mengmeng
Huang, Jingxin
Kang, Wen
Powiązania:
https://bibliotekanauki.pl/articles/173479.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
radio frequency signal generation
semiconductor optical amplifiers
four-wave mixing
Opis:
A novel scheme for photonic generation of broadly tunable radio frequency signal using a reflective semiconductor optical amplifier (RSOA) is demonstrated. A continuous wave emitted from the laser diode is modulated by a Mach–Zehnder modulator, then the modulated optical carrier is injected into the RSOA. Due to the four-wave mixing effect in the RSOA, the limited frequency components of the modulated signal are expanded, which directly lead to the generation of a wide frequency comb. Two optical tunable bandpass filters are parallelly connected to select the desired sidebands, which are launched into a photodetector or photomixer to generate radio frequency signal by beating. Using the proposed method, the bandwidth of generated radio frequency signal can range from 20 to 300 GHz.
Źródło:
Optica Applicata; 2019, 49, 1; 27-36
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vibration transients of reservoir-pipe-valve system caused by water hammer
Autorzy:
Miao, Yang
Jiang, Yuncheng
Qiu, Zaihui
Pan, Jun
Wang, Lu
Han, Zhenrong
Li, Kun
Zhang, Li
Zhang, Xiaolu
Powiązania:
https://bibliotekanauki.pl/articles/1839616.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
reservoir-pipe-valve system (RPV system)
water hammer
vibration
transients
Opis:
A severe oscillation, accompanied with an abnormal “click” sound, of a fuel feeding pipe system during valve closing, when the feeding flowrate reaches a certain value, is observed experimentally. A fluctuation model in which stiffness and damping coefficients of the vibration system are time varying is proposed. Each coefficient is composed of two parts, one of which is constant and the other is time varying. Based on this model, simulation transients of the vibration displacement, velocity and pressure in the pipe are presented. Simulations of the pressure transients are compared with experimental data detected by pressure transducer, which shows that both have fluctuations in the transient process at a large flowrate.
Źródło:
Journal of Theoretical and Applied Mechanics; 2020, 58, 4; 1037-1048
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on strength characteristics and permeability of chlorite schist during triaxial compression permeability
Autorzy:
Wang, Fuqi
Xue, Weipei
Qiao, Zhongdong
Wu, Jun
Jing, Laiwang
Powiązania:
https://bibliotekanauki.pl/articles/27312096.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
łupek chlorynowy
charakterystyka wytrzymałościowa
przepuszczalność
kompresja trzyosiowa
opaska kompresyjna
chlorite schist
strength characteristic
permeability
triaxial compression
compression band
Opis:
In order to grasp the strength characteristics and permeability of chlorite schist, the triaxial compression permeability test of chlorite schist was carried out by using a rock triaxial servo testing machine equipped with seepage device. Based on the test results, the failure strength, initial permeability and permeability development of rock samples under different confining pressure and different pore water pressure are compared, and the failure types of rock samples under triaxial compression permeability and their influence on permeability are analyzed. The results show that the increase of confining pressure is conducive to the improvement of failure strength of chlorite schist, and the increase of pore water pressure reduces the failure strength, which is related to the inhibition of crack development in rock samples by confining pressure and the promotion of crack expansion by pore water pressure. The mechanical deformation of chlorite schist in triaxial compression permeability process has experienced initial compaction stage, linear elastic stage and crack stable propagation to failure stage. As a consequence, permeability shows three trends of decline, stable development and rise, which is closely related to the development of the internal structure of rock samples at each stage. During the failure of triaxial compression permeability, there is a local compression zone in chlorite schist, and the rising rate slows down due to the influence of the compression zone.
Źródło:
Archives of Civil Engineering; 2023, 69, 2; 353--365
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of Clothing Image Classification Models: A Comparison Study between Traditional Machine Learning and Deep Learning Models
Autorzy:
Xu, Jun
Wei, Yumeng
Wang, Aichun
Zhao, Heng
Lefloch, Damien
Powiązania:
https://bibliotekanauki.pl/articles/2200761.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
e-commerce
clothing image classification
traditional machine learning
CNN
HOG
SVM
small VGG network
Opis:
Clothing image in the e-commerce industry plays an important role in providing customers with information. This paper divides clothing images into two groups: pure clothing images and dressed clothing images. Targeting small and medium-sized clothing companies or merchants, it compares traditional machine learning and deep learning models to determine suitable models for each group. For pure clothing images, the HOG+SVM algorithm with the Gaussian kernel function obtains the highest classification accuracy of 91.32% as compared to the Small VGG network. For dressed clothing images, the CNN model obtains a higher accuracy than the HOG+SVM algorithm, with the highest accuracy rate of 69.78% for the Small VGG network. Therefore, for end-users with only ordinary computing processors, it is recommended to apply the traditional machine learning algorithm HOG+SVM to classify pure clothing images. The classification of dressed clothing images is performed using a more efficient and less computationally intensive lightweight model, such as the Small VGG network.
Źródło:
Fibres & Textiles in Eastern Europe; 2022, 5 (151); 66--78
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on intensive design and control of chamber group under the condition of weak surrounding rock
Autorzy:
Yang, Jun
Hou, Shilin
Zhou, Kaifang
Qiao, Bowen
Wang, Hongyu
Wei, Qinglong
Powiązania:
https://bibliotekanauki.pl/articles/88879.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
deep soft rock
chamber group
intensive design
field test
surrounding rock control
Opis:
In order to study the design and stability control of deep soft rock chamber group, taking ninth coal mine of Hebi Coal Power Co., Ltd. as the engineering background, The main problem in normal design is analyzed with the combined method of FLAC3D numerical simulation and field engineering test. and then puts forward targeted control measures and carries out field application. The results show that, compared with the conventional design, the intensive design can reduce the stress concentration degree and plastic zone range of the surrounding rock, as well as reduce the quantities. Compared with conventional supporting schemes, the surrounding rock deformation greatly reduces by more than 82% after adopting bolting and shotcreting with wire mesh + anchor cable + floor anchor supporting. Among them, the floor heave control has obvious effect, and the decreasing amplitude reaches more than 93%. The field application shows that the surrounding rock deformation of the main chamber is within the allowable range, and the chamber control effect is good. Therefore, the research results can provide reference for the design and control of similar chamber groups.
Źródło:
Mining Science; 2019, 26; 223-240
2300-9586
2353-5423
Pojawia się w:
Mining Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measuring the Geometrical Parameters of Slub Yarn Using a Computer Vision Based Image Sequencing Technique
Pomiar parametrów geometrycznych przędzy fantazyjnej za pomocą techniki sekwencjonowania obrazów opartej na obrazie komputerowym
Autorzy:
Li, Zhongjian
Xiang, Jun
Wang, Lei
Zhang, Ning
Wang, Jing-an
Pan, Ruru
Gao, Weidong
Powiązania:
https://bibliotekanauki.pl/articles/231514.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
slub yarn sequence image
geometrical parameter measurement
image segmentation
image stitching
przędza fantazyjna
pomiary parametrów geometrycznych
obraz komputerowy
Opis:
This article presents a computer vision method for measuring the geometrical parameters of slub yarn based on yarn sequence images captured from a moving slub yarn. An image segmentation method proposed by our earlier work was applied to segment sequence slub yarn images to obtain overlapping diameter data. Then an image stitching method was proposed to remove the overlapped data based on the normalised cross correlation (NCC) method. In order to detect the geometrical parameters of slub yarn, the frequency histogram, curve fitting , and spectrogram methods were adopted to analyse the sequence diameter data obtained. Four kinds of slub yarn with different geometrical parameters were tested using the method proposed and Uster method. The experimental results show that the detection results for slub amplitude, slub length, slub distance, and slub period obtained using the method proposed were consistent with the set values and Uster results.
W artykule przedstawiono komputerową metodę pomiaru parametrów geometrycznych przędzy fantazyjnej na podstawie sekwencjonowania obrazów. Metoda segmentacji obrazu zaproponowana we wcześniejszej pracy została zastosowana do obrazów przędzy fantazyjnej w celu uzyskania danych dotyczących pomiarów średnicy. Następnie, w celu usunięcia nakładających się danych, zaproponowano metodę obróbki obrazu opartą o znormalizowaną metodę korelacji krzyżowej (NCC). W celu wykrycia parametrów geometrycznych przędzy fantazyjnej zastosowano histogram częstotliwości oraz dopasowanie krzywej i metody spektrogramowe do analizy uzyskanych danych. Za pomocą proponowanej metody i metody Uster przeanalizowano cztery rodzaje przędz fantazyjnych o różnych parametrach geometrycznych. Wyniki eksperymentalne wykazały, że wyniki detekcji amplitudy, długości, odległości i okresu wzgrubień uzyskane przy użyciu proponowanej metody były zgodne z wartościami zadanymi i wynikami Uster.
Źródło:
Fibres & Textiles in Eastern Europe; 2019, 3 (135); 26-35
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamic response analysis of light weight pyramidal sandwich plates subjected to water impact
Autorzy:
Wang, Hao
Zhao,, Fei
Liu, Jun
Tian, Yuan
Powiązania:
https://bibliotekanauki.pl/articles/259878.pdf
Data publikacji:
2012
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
light weight pyramidal sandwich plate structures (LWPSPS)
multi-physics numerical model
maximum deformation
quasi-static
local air cushion
Yuan-Sheng Cheng
Opis:
The fluid-solid interaction (FSI) dynamic responses for a Light Weight Pyramidal Sandwich Plate Structure (LWPSPS) under different water-entry velocities (1m/s-6m/s) are investigated numerically and theoretically. The characteristics of impact pressure and structure deformation are obtained by using LS-DYNA code based on the proposed 3D multi-physics (air-water-solid) FEM model. Numerical results show that the average water impact pressure of LWPSPS is much lower than that of the monolithic plate with same mass. Moreover, a phenomenon called “local air cushion” is observed for LWPSPS which does not exist for a monolithic plate. Theoretical hydroelasticity analysis demonstrates that the FSI effect of LWPSPS is weak when the ratio of water impact duration time to wet natural vibration period is greater than 4. In the study, an engineering estimation method to predict the maximum deformation of the LWPSPS is proposed, in which the total deformation is divided into two parts, i.e. local field deformation and global field deformation, and they are both computed using analytical model. Good agreement between the numerical results and ones obtained from the proposed engineering estimation method is achieved. Furthermore, the geometric variation sensitiveness analysis is also conducted.
Źródło:
Polish Maritime Research; 2012, 4; 31-43
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of the Effect of DINA on the Polymorphic Transition of ε-CL-20 in Composite Modified Double Base Propellants
Autorzy:
Wu, Zongkai
Zheng, Wei
Pei, Jiangfeng
Chen, Zhiqun
Zhang, Jun
Song, Xiuduo
Wang, Jiangning
Zhang, Dongxiang
Zhao, Fengqi
Powiązania:
https://bibliotekanauki.pl/articles/27788019.pdf
Data publikacji:
2021
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
CMDB propellant
CL-20
DINA
polymorphic transition
Opis:
Abstract: The polymorphic transition of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.05,9.03,11]dodecane (CL-20) is influenced by the materials and conditions used in the preparation of propellants, and limits the application of ε-CL-20 in solid propellants. In the present work, the effect of dinitroxydiethylnitramine (DINA) on the polymorphic transition of ε-CL-20 in CMDB propellants was investigated by Raman spectroscopy and the Calvet microcalorimeter method. The performance of propellants with CL-20 as affected by DINA was studied by the theoretical prediction of their energetic parameters, stability, combustion, and mechanical tests, respectively. The results showed that the polymorphic transition temperature of ε-CL-20 to α-CL-20 can be reduced to 75 °C by DINA. Expansion of the crystal volume during the process of the ε-CL-20 to α-CL-20 transition will produce obvious cracks in the surface of the crystals. NC/NG can inhibit the effect of DINA on the polymorphic transition of ε-CL-20. The theoretically predicted results indicated that adding DINA will not lower the energy level of CMDB propellants containing CL-20. The DSC and VST results showed that CL-20 has good compatibility and thermal stability with DINA. The burning rate tests revealed that adding DINA decreases the burning rates of CMDB propellants containing CL-20. Mechanical property testing showed that adding DINA can clearly improve the mechanical properties of CMDB propellants containing CL-20. The results of these investigations suggested that DINA has no effect on the crystalline stability of ε-CL-20 in the solventless extrusion process, which contributes to a significant understanding of practical applications and provides guidance for applied research on the use of CL-20 in propellants.
Źródło:
Central European Journal of Energetic Materials; 2021, 18, 2; 165--182
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application cumulative tensile explosions for roof cutting in Chinese underground coal mines
Autorzy:
Yang, Jun
Liu, Binhui
Bian, Wenhui
Chen, Kuikui
Wang, Hongyu
Cao, Chen
Powiązania:
https://bibliotekanauki.pl/articles/2073869.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
roboty strzałowe
wysadzanie skał
kopalnia
cumulative blast
bilateral cumulative tensile explosion
roof cutting and pressure relief technology
gob-side entry retaining
Opis:
Cumulative blasts are an important controlled blasting method used to control the propagation of cracks in the predetermined direction. However, traditional cumulative blasts are associated with long processing times and poor blasting effects. A simple blasting technology called bilateral cumulative tensile explosion (BCTE) is proposed in this paper. There are two application types where BCTE is used. The first application is used to control the stability of high-stress roadways in both Wangzhuang mine 6208 tailgate and Hongqinghe mine 3-1103 tailgate. The second application is used to replace the backfill body in gob-side entry retaining (GER) in Chengjiao mine 21404 panel, Jinfeng mine 011810 panel and Zhongxing mine 1200 panel. The first application type reveals that BCTE can significantly reduce the deformation of the surrounding rock and reduce the associated maintenance cost of the roadways. Whereas the second application type, the roadway deformations are smaller, the process is simpler, and the production costs are lower, which further promotes GER and is of significance towards conserving resources.
Źródło:
Archives of Mining Sciences; 2021, 66, 3; 421--435
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on the linear viscoelastic rheological properties of rejuvenated asphalt mastic based on the discrete element method
Autorzy:
Lin, Mei
Lei, Yu
Li, Ping
Shuai, Jun
Wang, Zhaoli
Powiązania:
https://bibliotekanauki.pl/articles/27312105.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
model konstytutywny
metoda elementów dyskretnych
mastyks asfaltowy odnowiony
właściwości reologiczne
constitutive model
discrete element method
rejuvenated asphalt mastic
rheological characteristics
Opis:
The rheological property of asphalt is an important factor affecting the pavement performance of asphalt binder, and the fundamental reason for the change of asphalt rheological property is the strong evolution of asphalt material meso structure. However, the internal mechanism of rejuvenated asphalt mastic system is complex and its rules are difficult to grasp. Aiming to study the relationship between meso mechanical parameters and rheological parameters of rejuvenated asphalt mastic, the meso structure model of rejuvenated asphalt mastic was established and improved based on the discrete element method. Moreover, the meso parameters of the model were obtained by the objective function method, and then the influences of various factors were studied to construct the mathematical constitutive model of rheological parameter modulus and meso mechanical parameters. Combing with the reliability of the improved Burgers model was verified based on the rheological test results of rejuvenated asphalt mastic. In addition, the virtual test of dynamic shear rheological dynamic frequency scanning was carried out on the asphalt mastic sample by particle flow software. By adjusting the mesomechanical parameters, the simulation results (complex shear modulus and phase angle) were consistent with the test results. This study clarified the relationship between mesomechanics and macro performance, and this model could be used to obtain the complex shear modulus of rejuvenated asphalt mastic under different types, filler-asphalt ratio and external force environments by adjusting particle flow, wall boundary and other conditions, which can greatly save the workload for the later research and provide a theoretical basis for production experiments.
Źródło:
Archives of Civil Engineering; 2023, 69, 2; 399--416
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on Scattering Feature Extraction of Underwater Moving Cluster Targets Based on the Highlight Model
Autorzy:
Yang, Yang
Fan, Jun
Wang, Bing
Powiązania:
https://bibliotekanauki.pl/articles/31339855.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
motion small cluster targets
feature fusion
azimuth trend scale
azimuth trend Doppler
Opis:
In detecting cluster targets in ports or near-shore waters, the echo amplitude is seriously disturbed by interface reverberation, which leads to the distortion of the traditional target intensity characteristics, and the appearance of multiple targets in the same or adjacent beam leads to fuzzy feature recognition. Studying and extracting spatial distribution scale and motion features that reflect the information on cluster targets physics can improve the representation accuracy of cluster target characteristics. Based on the highlight model of target acoustic scattering, the target azimuth tendency is accurately estimated by the splitting beam method to fit the spatial geometric scale formed by multiple highlights. The instantaneous frequencies of highlights are extracted from the time-frequency domain, the Doppler shift of the highlights is calculated, and the motion state of the highlights is estimated. Based on the above processing method, target highlights’ orientation, spatial scale and motion characteristics are fused, and the multiple moving highlights of typical formation distribution in the same beam are accurately identified. The features are applied to processing acoustic scattering data of multiple moving unmanned underwater vehicles (UUVs) on a lake. The results show that multiple small moving underwater targets can be effectively recognized according to the highlight scattering characteristics.
Źródło:
Archives of Acoustics; 2023, 48, 3; 235-247
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reliability analysis of complex uncertainty multi-state system based on Bayesian network
Zastosowanie sieci bayesowskiej do analizy niezawodności złożonych systemów wielostanowych w warunkach niepewności
Autorzy:
Wang, Haipeng
Duan, Fuhai
Ma, Jun
Powiązania:
https://bibliotekanauki.pl/articles/300676.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
reliability analysis
Bayesian network
complex uncertainty multi-state system
fuzzy mathematics
grey system theory
analiza niezawodności
sieć bayesowska
złożony system wielostanowy
niepewność
matematyka rozmyta
teoria szarych systemów
Opis:
Reliability analysis of complex multi-state system has uncertainty, which is caused by complex structures, limited test samples, and insufficient reliability data. By introducing fuzzy mathematics and grey system theory into the Bayesian network, the model of the grey fuzzy Bayesian network is built, and the reliability analysis method of complex uncertainty multi-state system with the non-deterministic membership function and the interval characteristic quantity is proposed in this paper. Using the trapezoidal membership function with fuzzy support radius variable to describe the fault state of the component, it can effectively avoid the influence of human subjective factors on the selection of the membership function and solve the problem that the fault states of the system and its components are difficult to define accurately. And the conditional probability table containing interval grey numbers is constructed to effectively express the uncertain fault logic relationship between the system and its components. Moreover, a parameter planning model of the system reliability characteristic quantities is constructed, and the system reliability characteristic quantities are expressed as the form of interval values. Finally, two sets of numerical experiments are conducted and discussed, and the results show that the proposed method is an effective and a promising approach to reliability analysis for complex uncertainty multi-state systems.
Analiza niezawodności złożonych systemów wielostanowych obarczona jest niepewnością związaną ze złożonością ich struktury, ograniczoną liczbą próbek badawczych i niewystarczającymi danymi dotyczącymi niezawodności. W przedstawionej pracy, wprowadzenie elementów matematyki rozmytej i teorii szarych systemów do sieci bayesowskiej umożliwiło budowę modelu szarej rozmytej sieci bayesowskiej i zaproponowanie metody analizy niezawodności złożonych systemów wielostanowych w warunkach niepewności, która wykorzystuje niedeterministyczną funkcję przynależności oraz pojęcie interwałowej wielkości charakterystycznej. Zastosowanie trapezoidalnej funkcji przynależności z rozmytą zmienną promienia nośnego do opisu stanu uszkodzenia komponentu, pozwala zniwelować wpływ subiektywnego czynnika ludzkiego na wybór funkcji przynależności i eliminuje konieczność precyzyjnego definiowania stanu uszkodzenia systemu i jego elementów składowych. Opracowana tabela prawdopodobieństw warunkowych zawierająca szare liczby interwałowe pozwala wyrazić niepewne zależności logiki uszkodzeń między systemem a jego składnikami. Ponadto, w pracy skonstruowano model planowania parametrów charakterystycznych wielkości niezawodności systemu wyrażonych w postaci wartości interwałowych. W ostatniej części artykułu omówiono dwie serie eksperymentów numerycznych, których wyniki pokazują, że proponowana metoda stanowi skuteczne i obiecujące podejście do analizy niezawodności złożonych systemów wielostanowych w warunkach niepewności.
Źródło:
Eksploatacja i Niezawodność; 2019, 21, 3; 419-429
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Observation and Modelling on the Shipping Noise in Shallow Waters with Complex Islands and Reefs of the East China Sea
Autorzy:
Peng, Zilong
Zhou, Fulin
Fan, Jun
Wang, Bin
Wen, Huabing
Powiązania:
https://bibliotekanauki.pl/articles/1953475.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
shipping noise
spectral source level
noise mapping
shallow water
merchant ship
Opis:
The impact of the noise radiated from merchant ships on marine life has become an active area of research. In this paper, a methodology integrating observation at a single location and modelling the whole noise field in shallow waters is presented. Specifically, underwater radiated noise data of opportunistic merchant ships in the waters of Zhoushan Archipelago were collected at least one day in each month from January 2015 to November 2016. The noise data were analyzed and a modified empirical spectral source level (SSL) model of merchant ships was proposed inspired by the RANDI-3 model (Research Ambient Noise Directionality) methodology. Then combining the modified model with the realistic geoacoustic parameters and AIS data of observed merchant ships, the noise mappings in this area were performed with N × 2D of Normal Mode calculations, in which the SSL of each ship was estimated using the modified model. The sound propagation at different receiving positions is different due to the shielding effect of islands and bottom topography. The methodology proposed in this paper may provide a reference for modelling shipping noise in shallow waters with islands and reefs.
Źródło:
Archives of Acoustics; 2021, 46, 2; 301-311
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Normal Mode Solutions of Target Strengths of Solid-filled Spherical Shells and Discussion of Influence Parameters
Autorzy:
Jia, Bing
Fan, Jun
Li, Gui-Juan
Wang, Bin
Chen, Yun-Fei
Powiązania:
https://bibliotekanauki.pl/articles/31339751.pdf
Data publikacji:
2024
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
solid-filled spherical shell
room temperature vulcanized silicone rubber
target strength enhancement
Opis:
The normal mode solution for the form function and target strength (TS) of a solid-filled spherical shell is derived. The calculation results of the spherical shell’s acoustic TS are in good agreement with the results of the finite element method (FEM). Based on these normal mode solutions, the influences of parameters such as the material, radius, and thickness of the inner and outer shells on the TS of a solid-filled spherical shell are analyzed. An underwater spherical shell scatterer is designed, which uses room temperature vulcanized (RTV) silicone rubber as a solid filling material and does not contain a suspension structure inside. The scatterer has a good TS enhancement effect.
Źródło:
Archives of Acoustics; 2024, 49, 1; 83-93
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Yarn-Dyed Fabric Image Retrieval Using Colour Moments and the Perceptual Hash Algorithm
Otrzymywanie obrazu tkaniny wytworzonej z barwionych przędz przy zastosowaniu metody momentów barwnych i percepcyjnego algorytmu z mieszaniem
Autorzy:
Li, Zhongjian
Xiang, Jun
Wang, Lei
Zhang, Ning
Pan, Ruru
Gao, Weidong
Powiązania:
https://bibliotekanauki.pl/articles/232957.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
yarn-dyed fabric
image retrieval
colour moments
perceptual hash algorithm
Hamming distance
przędza barwiona
obrazy wzorów tkanin
metoda momentów barwnych
percepcyjny algorytm mieszania
odległość Hamminga
Opis:
Due to the variety of yarn colours and arrangement, it is a challenging problem to retrieve a yarn-dyed fabric image. In this paper, yarn-dyed fabric samples are captured by the DigiEye system first, and then pattern images of the fabric images captured are simulated by pattern design software based on extracted structure parameters of the yarn-dyed fabric. For the simulated pattern image, an effective algorithm is proposed to retrieve these kinds of images by combining the colour moments method and perceptual hash algorithm. Then the pattern images retrieved are mapped back to the yarn-dyed fabric image so as to realise the yarn-dyed fabric image retrieval. In the algorithm proposed, the colour moments method is adopted to extract the colour features, and the perceptual hash algorithm is utilised to calculate the spatial features of the simulated pattern images. Then the two kinds of image features are used to compute the similarity between the input original image and each target image based on the Euclidean distance and Hamming distance. Relevant images can be retrieved in dependence on the similarity value, which is determined by calculating the optimum weighted value of the colour features’ similarity and spatial features’ similarity. In order to measure the retrieval efficiency of the method proposed, the accuracy rate and retrieval rate of image retrieval were computed in experiments using a PATTERN image database with 300 images. The experimental results show that the average accuracy rate of the method proposed is 85.30% and the retrieval rate - 53.51% when the weighted value of the colour feature similarity is fixed at 0.45 and the spatial feature similarity is 0.55. It is shown that the method presented is effective to retrieve pattern images of yarn-dyed fabric.
Ze względu na różnorodność kolorów i rozmieszczenia przędz otrzymanie obrazu tkaniny wytworzonej z barwionych przędz jest trudnym zadaniem. W artykule próbki tkanin z barwionych przędz były najpierw analizowane przez system DigiEye, a następnie wykonane zostały symulacje obrazów z zastosowaniem oprogramowania do projektowania wzorów oparte na wyodrębnionych parametrach struktury tkaniny. W przypadku symulacji obrazu wzoru zaproponowano skuteczny algorytm do odzyskiwania tego rodzaju obrazów poprzez połączenie metody momentów koloru i percepcyjnego algorytmu z mieszaniem. W zaproponowanym algorytmie do wyodrębniania cech kolorów zastosowano metodę momentów barwnych, a do obliczenia cech przestrzennych symulowanych obrazów został wykorzystywany percepcyjny algorytm mieszania. Następnie użyto dwóch rodzajów cech obrazu do obliczenia podobieństwa między oryginalnym obrazem wejściowym a każdym obrazem docelowym w oparciu o odległość euklidesową i odległość Hamminga. Odpowiednie obrazy można odzyskać w zależności od wartości podobieństwa, która jest określana przez obliczenie optymalnej ważonej wartości podobieństwa cech koloru i podobieństwa cech przestrzennych. Aby zmierzyć skuteczność proponowanej metody w eksperymentach obliczono wskaźnik dokładności i szybkość pobierania obrazów, wykorzystując bazę danych obrazów PATTERN z 300 obrazami. Wyniki eksperymentalne pokazały, że średni współczynnik dokładności proponowanej metody wynosi 85,30%, a szybkość pobierania 53,51%, wartość podobieństwa cech kolorów wynosiła 0,45, a podobieństwo cech przestrzennych wynosiło 0,55. Wykazano, że prezentowana metoda jest skuteczna w przypadku otrzymywania obrazów wzorów tkanin z przędz barwionych.
Źródło:
Fibres & Textiles in Eastern Europe; 2019, 5 (137); 39-46
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on the Performance Optimization of Turbulent Self-Noise Suppression and Sound Transmission of Acoustic Windows Made from Functionally Graded Material
Autorzy:
Li, Bing
Zhou, Fu-Lin
Fan, Jun
Wang, Bin
Tan, Liwen
Powiązania:
https://bibliotekanauki.pl/articles/31339793.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
functionally graded material
acoustic window
turbulent self-noise
sound transmission loss
optimization
Opis:
For a simplified sonar dome model, an optimization method for internal gradients of functionally graded material (FGM) acoustic windows is proposed in this paper. This method can be used to design optimized FGM acoustic windows with better turbulent self-noise suppression and sound transmission performances. A theoretical model of FGM acoustic windows to evaluate the reduction of self-noise caused by the turbulent boundary layer (TBL) pulsating pressure and the sound transmission loss (STL) is derived through the double Fourier transform and the wavenumber frequency spectrum analysis, respectively, based on the transfer matrix idea and the classical elastic theory. The accuracy of the theory is verified by the finite element results of COMSOL Multiphysics. Utilizing the genetic algorithm (GA) and taking the monotonic gradient as the constraint condition, the internal gradient optimization method of FGM acoustic windows obtains the optimization variables in the Bernstein polynomial when the optimization objective is minimized by iterating the optimization variables in the deviation function represented by the Bernstein polynomial that is introduced in the gradient function. The STL, the turbulent self-noise reduction or a weighting function of the STL and turbulent self-noise reduction of FGM acoustic windows is chosen as the optimization objective. The optimization calculation of the sound transmission or turbulent self-noise suppression performances is carried out for the FRP-rubber FGM (FGM with fiber reinforced plastic (FRP) as the substrate material and rubber as the top material) acoustic window. The optimized results show that both the sound transmission and turbulent self-noise suppression performance are effectively improved, which verifies the effectiveness of the optimization method. Finally, the mechanism of the sound transmission and self-noise suppression characteristics before and after optimization are explained and analyzed based on the equivalent model of graded materials. The research results of this paper provide a reference value for the future design of FGM acoustic windows for sonar domes.
Źródło:
Archives of Acoustics; 2023, 48, 4; 475-495
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Solvent-free synthesis of 1-amidoalkyl-2-naphthol and 3-amino-1-phenyl-1H benzo[f]chromene-2-carbonitrile derivatives by Fe3O4@enamine-B(OSO3H)2 as an efficient and novel heterogeneous magnetic nanostructure catalyst
Autorzy:
Li, Fangping
Zhang, Jun
Wang, Longjiang
Liu, Weijian
Yousif, Qahtan A.
Powiązania:
https://bibliotekanauki.pl/articles/778863.pdf
Data publikacji:
2020
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
1-amidoalkyl-2-naphthol
3-amino-1-phenyl-1H benzo[f]chromene-2-carbonitrile
solvent-free conditions
magnetic
catalyst
Opis:
A green procedure for the one-pot three-component synthesis of 1-amidoalkyl-2-naphthol and 3-amino-1-phenyl-1H benzo[f]chromene-2-carbonitrile derivatives from the reaction of 2-naphtol, aldehydes, and malononitrile/acetamide in the presence of a catalytic amount of Fe3O4@enamine-B(OSO3H)2 as an efficient and novel heterogeneous magnetic nanostructure catalyst is described. The catalyst was characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). These strategies possess some merits such as simple work-up method, easy preparation of the catalyst, short reaction times, good-to-high yields, and non-use of hazardous solvents during all steps of the reactions. Moreover, due to the magnetic nature of the catalyst, it was readily recovered by magnetic decantation and can be recycled at least six runs with no considerable decrease in catalytic activity.
Źródło:
Polish Journal of Chemical Technology; 2020, 22, 2; 9-19
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-42 z 42

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