Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Feng, Xiao" wg kryterium: Autor


Wyświetlanie 1-11 z 11
Tytuł:
A new low SNR underwater acoustic signal classification method based on intrinsic modal features maintaining dimensionality reduction
Autorzy:
Ju, Yang
Wei, Zhengxian
Li, Huangfu
Feng, Xiao
Powiązania:
https://bibliotekanauki.pl/articles/259300.pdf
Data publikacji:
2020
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
acoustic
low SNR
signal classification
feature maintain
dimension reduction
Opis:
The classification of low signal-to-noise ratio (SNR) underwater acoustic signals in complex acoustic environments and increasingly small target radiation noise is a hot research topic. . This paper proposes a new method for signal processing—low SNR underwater acoustic signal classification method (LSUASC)—based on intrinsic modal features maintaining dimensionality reduction. Using the LSUASC method, the underwater acoustic signal was first transformed with the Hilbert-Huang Transform (HHT) and the intrinsic mode was extracted. the intrinsic mode was then transformed into a corresponding Mel-frequency cepstrum coefficient (MFCC) to form a multidimensional feature vector of the low SNR acoustic signal. Next, a semi-supervised fuzzy rough Laplacian Eigenmap (SSFRLE) method was proposed to perform manifold dimension reduction (local sparse and discrete features of underwater acoustic signals can be maintained in the dimension reduction process) and principal component analysis (PCA) was adopted in the proces of dimension reduction to define the reduced dimension adaptively. Finally, Fuzzy C-Means (FCMs), which are able to classify data with weak features was adopted to cluster the signal features after dimensionality reduction. The experimental results presented here show that the LSUASC method is able to classify low SNR underwater acoustic signals with high accuracy.
Źródło:
Polish Maritime Research; 2020, 2; 187-198
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Proficiency effect on L2 pragmatic competence
Autorzy:
Xiao, Feng
Powiązania:
https://bibliotekanauki.pl/articles/780487.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
proficiency effect
L2 pragmatic competence
Opis:
This paper synthesizes cross-sectional studies of the effect of proficiency on second language (L2) pragmatics to answer the synthesis question: Does proficiency affect adult learners’ pragmatic competence? Findings have revealed an overall positive proficiency effect on pragmatic competence, and in most cases higher proficiency learners have higher pragmatic competence. However, increased proficiency does not guarantee a native-like pragmatic performance because proficiency effect varies depending on the nature of target pragmatic features such as types of speech acts (degrees of directness and conventionality) (e.g., Cook & Liddicoat, 2002; Félix-Brasdefer, 2007), modalities of pragmatic performance (comprehension and production) (e.g., Bradovi-Harlig, 2008, 2009), social variables involved in task situations, such as social status (e.g., Allami & Naeimi, 2011), social distance (e.g., Maeshiba, Yoshinaga, Kasper, & Ross, 1996), and power relationship (e.g., Al-Gahtani & Roever, 2012). Moreover, proficiency effect is mediated by contextual variables such as length of stay in the target language community (e.g., Shardakova, 2005; Taguchi, 2011, 2013; Xu, Case, & Wang, 2009).
Źródło:
Studies in Second Language Learning and Teaching; 2015, 5, 4; 557-581
2083-5205
2084-1965
Pojawia się w:
Studies in Second Language Learning and Teaching
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation of Insensitive RDX by Suspension Spray Technology and Its Characterization
Autorzy:
Yan, Xiang
Li, Xiao Dong
Zhou, Peng
Ji, Wei
Shi, Xiao Feng
Powiązania:
https://bibliotekanauki.pl/articles/358585.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
RDX
Estane 5703
suspension spray technology
detonation velocity
insensitivity
Opis:
A new insensitive and high energy explosive based on RDX was prepared by suspension spray technology using Estane 5703 as a binder (e-RDX). Scanning electron microscopy was used to characterize the morphology and particle size of the samples. The composite was analyzed by differential scanning calorimetry and X-ray photoelectron spectroscopy. Its impact sensitivity and detonation velocity were determined. For comparison, raw RDX, refined RDX (r-RDX) and solution spray dried RDX/Estane 5703 (e1-RDX) were also tested using these five methods. The SEM results showed that the e-RDX size was 1-3 μm. e1-RDX exhibited a spherical shape with some defects on the surface. The XPS results indicated that Estane 5703 can be successfully coated onto the surface of e-RDX. Compared to raw RDX, the drop height of r-RDX, e1-RDX and e-RDX was increased, being 16.5 cm, 32.9 cm and 58.4 cm, respectively. The activation energy of e-RDX is lower than that of raw RDX, but a little higher than that of e1-RDX. Compared to raw RDX, the detonation velocity of r-RDX, e1-RDX, w-RDX and e-RDX had decreased, being 110 m·s–1, 710 m·s–1, 410 m·s–1 and 210 m·s–1, respectively.
Źródło:
Central European Journal of Energetic Materials; 2019, 16, 2; 216-227
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on flotation behavior and mechanism of separating chalcopyrite and Molybdenite with ethyl mercaptoglycolate as inhibitor
Autorzy:
Yang, Xiao-Feng
Xu-Zhao
Liu, Yao-Yao
Powiązania:
https://bibliotekanauki.pl/articles/24085868.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
ethyl thioglycolate
chalcopyrite
molybdenite
inhibitor
separation
Opis:
The effect of ethyl thioglycolate organic small molecule inhibitors on chalcopyrite molybdenite flotation behaviour is investigated via single mineral micro-flotation tests, zeta potential tests, and X-ray photoelectron spectroscopy (XPS) analysis. Results of the flotation test indicate that ethyl thioglycolate organic small-molecule inhibitors can effectively separate Cu and Mo and selectively inhibit chalcopyrite under weak alkaline conditions. Infrared spectroscopy and XPS analysis show that hydrophilic functional groups C=O and -COOH in the ethyl thioglycolate organic small molecules can chemically adsorb onto the chalcopyrite surface. Moreover, ethyl thioglycolate has no obvious effect on zeta potential of molybdenite. Therefore, ethyl thioglycolate can effectively separate chalcopyrite and molybdenite.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 2; art. no. 162824
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hereditary Equality of Domination and Exponential Domination in Subcubic Graphs
Autorzy:
Chen, Xue-Gang
Wang, Yu-Feng
Wu, Xiao-Fei
Powiązania:
https://bibliotekanauki.pl/articles/32324524.pdf
Data publikacji:
2021-11-01
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
dominating set
exponential dominating set
subcubic graphs
Opis:
Let γ(G) and γe(G) denote the domination number and exponential domination number of graph G, respectively. Henning et al., in [Hereditary equality of domination and exponential domination, Discuss. Math. Graph Theory 38 (2018) 275–285] gave a conjecture: There is a finite set ℱ of graphs such that a graph G satisfies (H) = γe(H) for every induced subgraph H of G if and only if G is ℱ-free. In this paper, we study the conjecture for subcubic graphs. We characterize the class ℱ by minimal forbidden induced subgraphs and prove that the conjecture holds for subcubic graphs.
Źródło:
Discussiones Mathematicae Graph Theory; 2021, 41, 4; 1067-1075
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electronic Structure and Magnetic Exchange Interaction in Fe₂NiAs Compound
Autorzy:
Wei, Xiao-Ping
Zhang, Ya-Ling
Sun, Xiao-Wei
Song, Ting
Zhu, Xing-Feng
Powiązania:
https://bibliotekanauki.pl/articles/1033418.pdf
Data publikacji:
2017-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.20.Lp
71.20.Gj
71.20.-b
77.80.B-
Opis:
Using the spin-polarized relativistic Korringa-Kohn-Rostoker method, we study the electronic and magnetic properties of Fe₂NiAs compound with the Hg₂CuTi structure. Electronic calculations reveal the d-d orbital hybridization taking an important role in the compound. The calculated magnetic moments, which contain the spin and orbital moments, are primarily carried by Fe atoms located in A and B sites. The orbital moment of Fe₂NiAs system is rather small due to the cause of orbital quenching, implying a weak spin-orbit coupling. Simultaneously, we also study the influence of lattice constant on the magnetic moment, it is found that both spin and orbital moments are sensitive to the changes of lattice constants, i.e., the moments become larger as the expansion of lattice constant, indicating the enhancement of spin-orbit coupling effect. In addition, we investigate the magnetic interactions between the constituents to obtain the Heisenberg exchange coupling parameters. It is noted that the interactions are dominated by a strong exchange between Fe atoms. Finally, we acquire the Curie temperatures of Fe₂NiAs compound under different lattice constants by using mean field approximation.
Źródło:
Acta Physica Polonica A; 2017, 132, 4; 1320-1324
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal error modeling of spindle and dynamic machining accuracy reliability analysis of CNC machine tools based on IA and LHSMC
Autorzy:
Zhang, Ziling
Feng, Shuo
Ding, Yan
Mei, Xiao
Tao, Zhiqiang
Powiązania:
https://bibliotekanauki.pl/articles/2057984.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
electric spindle unit
thermal error
latin hypercube sampling monte carlo method
finite element simulation
machining accuracy reliability
Opis:
Machining accuracy reliability as a key index of CNC machine tools is seriously influenced by the geometric and thermal errors. In the paper, a spindle unit thermal error modeling and machining accuracy reliability analysis method is proposed. By analyzing the heat generation mechanism, a thermal error model was developed to describe the thermal deformation of the electric spindle. Based on the immune algorithm (IA), the heat generation power and the heat transfer coefficient were optimized, and the thermal error was obtained by finite element thermal-mechanical coupling. By adopting the multi-body system theory (MBS), a dynamic machining accuracy model was put forward including the geometric and thermal errors. Based on the Latin hypercube sampling Monte Carlo method (LHSMC), a machining accuracy reliability analysis method was proposed to characterize the machining accuracy reliability considering the geometric and thermal errors. The method was employed to a machine tool, and the experimental results indicate the verification and superiority of the method.
Źródło:
Eksploatacja i Niezawodność; 2022, 24, 1; 100--113
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on the behavior of streamwise vortices formed between leading edge tubercles in a compressor cascade
Autorzy:
Zheng, Tan
Qiang, Xiao-Qing
Teng, Jin-Fang
Feng, Jin-Zhang
Powiązania:
https://bibliotekanauki.pl/articles/281149.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
compressor cascade
flow separation
leading edge tubercles
streamwise vortices
formation mechanism
Opis:
A study has been carried out to investigate the formation mechanism and development of streamwise vortices induced by leading edge tubercles in a high speed compressor cascade. The preliminary assessment of the cascade performance in terms of the total pressure loss coefficient shows that the loss reduction is achieved at high incidence angles. A smaller wavelength leads to higher additional losses at the design point, but gives rise to a greater loss reduction at high incidence angles. The modified cascade with a tubercle wavelength of 4% chord achieves the maximum loss reduction of 36.1% at i = 10◦ , as well as the stall angle improvement of 27.6%. The formation mechanism of streamwise vortices is elaborated on the basis of the streamwise vorticity equation, in which the streamwise turning terms may be responsible for the generation of streamwise vortices. Slices of streamwise vorticity at various streamwise locations, combined with vorticity strength distributions, have been presented to study the development of streamwise vortices. The counter-rotating vortices are divided into the crest-induced streamwise vortices (CSVs) and trough-induced streamwise vortices (TSVs). A streamwise vortex pair formed from a part of the CSV sheets behind troughs, is gradually entrained by the TSV pair along the streamwise direction. In addition, the tubercles with a smaller wavelength result in higher streamwise vorticity strength with which the streamwise vortices interact with the flow separation more sufficiently and delay the separation to a greater extent.
Źródło:
Journal of Theoretical and Applied Mechanics; 2019, 57, 3; 617-629
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ezetimibe prevents myocardial remodeling in an obese rat model by inhibiting inflammation
Autorzy:
Li, Xiao-Xing
Zhao, Lang
Chang, Ying
Liu, Bao-Shan
Xu, Feng
Zhang, Cheng
Ji, Xiao-Ping
Chen, Yu-Guo
Li, Chuan-Bao
Powiązania:
https://bibliotekanauki.pl/articles/1038380.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
obese
inflammation
remodeling
ezetimibe
IL-6
Opis:
Inflammation plays an important role in the development of many obesity-related diseases. This study aimed to investigate the effect of ezetimibe on inflammation and myocardial remodeling in obese rats. A rat model of obesity was established, and myocardial damage was examined by transmission electron microscopy and Masson staining. Twenty obese rats were divided into two groups (n=10): obese group and ezetimibe group. Ten SD rats were used as controls. Western blot was performed to monitor the expression of P-p38MAPK and interleukin (IL)-6. Immunohistochemical staining was used to monitor the expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. In the obese rats group, we observed increased inflammatory factors and myocardial hypertrophy. In contrast, the ezetimibe group exhibited decreased expression of inflammatory factors and an improvement in myocardial remodeling compared to the obese group. Mechanistically, we found that ezetimibe decreased P-p38MAPK, IL-6, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 levels in the hearts of the obese rats. Taken together, these results indicate that ezetimibe may improve myocardial remodeling in obese rats by inhibiting inflammation.
Źródło:
Acta Biochimica Polonica; 2018, 65, 3; 465-470
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
NEW BETULIN NITRATES: SYNTHESIS, CYTOTOXIC ACTIVITY AND MOLECULAR DOCKING EVALUATION
Autorzy:
Feng, GaiLi
Wang, Tao
Zhang, Rong
Luo, Jin
Xiao, MinJie
He, BaoEn
Liu, YongQian
Wu, JunXiao
Powiązania:
https://bibliotekanauki.pl/articles/895411.pdf
Data publikacji:
2018-10-31
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
Molecular docking
anti-tumor
Betulin nitrates
NO donors
Opis:
Betulin and its derivatives have been reported to affect several key genes of cell-cycle regulators. However, their specific targets haven’t yet been discovered. As an important cell cycle regulator, Cyclin-dependent kinase-2 (CDK2) has become a potential target for cancer therapy. Here we describe the design, synthesis and antitumor activities in vitro of eleven new betulin nitrates. The results revealed that compound (20) possesses potent antitumor activity against MCF-7 cell lines (IC50 < 10 μM). In order to investigate potential protein target, betulin nitrates were subjected to docking studies with CDK2. Compound (20) showed very good binding affinity for CDK2 via hydrogen bonding interactions. Thus, the CDK2 inhibitory potential could make compound (20) possible candidate as antitumor agent.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2018, 75, 5; 1135-1145
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characteristics and metal leachability of natural contaminated soil under acid rain scenarios
Autorzy:
Tan, Wenfa
Li, Yuan
Ding, Lei
Wang, Yachao
Li, Jiangxiang
Deng, Qinwen
Guo, Feng
Xiao, Xue
Powiązania:
https://bibliotekanauki.pl/articles/205435.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
heavy metal
soil pollution
fraction analysis
soil leaching
Opis:
Contamination of soil with heavy metals has become a worldwide environmental problem, and receives great attention. In this study, we aim to investigate soil pollution level affected by an industrial district nearby. The total amount of typical heavy metals in the soils (Hengyang Songmu Industrial Park, Hunan Province, China) was analyzed. In addition, the fraction analysis and laboratory simulation leaching via different pH rainwater was carried out to study the migration and transformation of heavy metals. The main results show that the contents of Cu, Zn, Pb, Cr and Cd in the samples were higher than the soil background values in Hunan Province. The heavy metals forms, analyzed by sequential extraction method, show that the proportion of the unstable form of Cd, Zn and Pb was more than 50%. Igeo values indicate that the heavy metal pollution degree of soil sample #5 at the investigated area is recorded in the order of Cd(6.42), Zn(2.28), Cu(1.82), Pb(1.63), and Cr(0.37). Cu, Zn, Pb, Cr and Cd in this area could pose a potential leaching risk to the environment which may affect the food chain and constitute a threat to human health. It would be necessary to take steps to stabilize and monitor the heavy metals in soil.
Źródło:
Archives of Environmental Protection; 2019, 45, 2; 91-98
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-11 z 11

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies