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The effect of positive/negative ion on the dust grain charging process in a Vasyliunas-Cairns (VC)-distributed dusty plasma system

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Plasma Science and Technology 2019年第6期21卷 58-62页

作者： N AHmAd A A ABId Y AL-HAdEETHI m N S QURESHI Saqib REHmAN department of Engineering and Applied Physics University of Science and Technology of China Hefei 230026 People's Republic of China CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary ScienceUniversity of Science and Technology of China Hefei 230026 People's Republic of China department of Physics Faculty of Sciences King Abdulaziz Unniversity Jeddah 21589 Saudi Arabia department of Physics GC University Lahore 54000 Pakistan department of Chemical Physics University of Science and Technology of China Hefei 230026People's Republic of China

Charging mechanism of dust particles has been considered as a growing research area in dusty plasma physics because of its exciting *** this paper,we consider a low-temperature non-equilibrium multispecies plasma model,which consists of Vasyliunas-Caims (VC) distributed electrons,negative/positive streaming ions,and negatively-charged dust grains to explain the charging mechanism of dust *** main theme of this work is to derive expressions of currents for negatively-charged dust grains (considering an equilibrium state position) in the plasma environment comprised of electrons and positive/negative streaming ions using the VC distribution *** proposed model shows that the dust grain surface potential is significantly affected by different plasma parameters such as the negative ion streaming velocity (Sn),positive ion streaming velocity (Si),spectral indices of VC distribution,negative ion charging state (Zn),positive ion charging state (Zi),and negative ion number density (ρ).

关键词： dust grain surface potential vasyliunas-cairns power law velocity distribution function multi species plasma

On the Generation of Strong Core Field Inside Flux Rope:2-d mHd and Hall mHd Simulation

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On the Generation of Strong Core Field Inside Flux Rope:2-D ...

The Philippine National Collection of microorganisms (PNCm):Repository of microbial diversity of the Country

中国空间科学学会空间物理学专业委员会第十五届全国日地空间物理学研讨会

作者： Y.Pang m.Zhou S.Y.Huang X.H.deng Z.G.Yuan X.J.Xu H.m.Li d.d.Wang Institute of Space Science and Technology Nanchang University Institute of Astronomy Nanchang University School of Electronic and Information Wuhan University

2-d mHd and Hall mHd simulations are carried out to study the generation of the enhancement of core field inside flux ***,we systemically investigate the growth of core fieldoyB,at the center of the flux rope(the O point),with or without Hall *** contrary to previous simulation results[Liu et al.,2009],we find that a nonlinear growth ofoyB,is simply due to the interaction between two reconnection jets ejected from two adjacent X lines,rather than the interaction between the Hall effect and pre-existed guide *** develop a simple theoretical model to semi-quantitatively describe how such an interaction(between reconnection jets)causes the explosive growth ofoyB,.In addition,we also find that Hall magnetic field can directly contributes to the enhancement ofoyB,via"re-reconnection"process in small scale flux rope and will lead to the saturated value ofoyB,slightly higher than those of large ones.

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Journal of Ocean University of Qingdao 2002年第1期1卷 101-104页

作者： monsalud R.G. magbanua F.O. Parungao m.P. Banaay C.G.B. Bayer m.H.d. Yap J.K. Tapay L.m. Philippine National Collection of microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines

The prime function of the Philippine National Collection of microorganisms (PNCm), being the national repository of microbial strains, is to collect and preserve strains for their continued viability and availability for future use. To date, a total of 2144 strains of bacteria (1357), yeasts (250), filamentous fungi (377), algae (14), and strains still to be identified (146) are maintained at the PNCm. These are preserved and maintained using various methods which include modified liquid drying (lyophilization), ultra-low temperature (-70℃) storage in 10% glycerol, storage in sterile soil, distilled water and overlaying with mineral oil. Periodic viability testing is done to assess the stability of these preserved cultures under storage. Aside from preservation and maintenance of cultures, the PNCm is also involved in several research activities. One of these is the isolation, characterization and identification of some Vibrio isolates from the Philippines. details on this particular study is presented in this report.

关键词：收藏文化菲律宾人微生物多样性细菌

Improving the classifcation accuracy using biomarkers selected from machine learning methods

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Control Theory and Technology 2021年第4期19卷 538-543页

作者： Linduni m.Rodrigo Ashoka d.Polpitiya department of mathematics and Statistics University of SydneySydneyNSW 2006Australia Colombo School of Business and management ColomboSri Lanka

High-dimensional data encountered in genomic and proteomic studies are often limited by the sample size but has a higher number of predictor *** selecting the most relevant variables that are correlated with the outcome variable is a crucial *** paper describes an approach for selecting a set of optimal variables to achieve a classifcation model with high predictive *** work described using a biological classifer published elsewhere but it can be generalized for any application.

关键词： Classifcation Variable selection Reversal Regression

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Journal of Rare Earths 2018年第10期36卷 1106-1111页

作者： Sardar Ahmad m.Shafiq Rashid Ahmad S.Jalali-Asadabadi Iftikhar Ahmad department of Chemistry University of Malakand Center for Computational materials Science University of Malakand department of Physics Abbottabad University of Science and Technology department of Physics Faculty of SciencesUniversity of Isfahan

In this paper, we explored the structural, elastic and mechanical properties of the strongly correlated electron systems, intermetallic Ln-Au（Ln = Ce, Pr, Nd, Gd, Tb, dy, Ho, Er, Tm, Yb, Lu） in cubic structure,using PF-LAPW method within the density functional theory. Structural properties of these intermetallics were investigated by treating the exchange-correlation potential with the GGA-PBE, GGA-PBEsol and GGA ＋ U. The effectiveness of the U for the structural properties as compared to other methods confirms the strong correlated nature of these compounds and the calculated lattice constants endorse the divalency of Yb. The results demonstrate the stable cubic CsCl structure of these compounds. Bulk modulus, Young＇s modulus, shear modulus, B/G ratio, Cauchy pressure, Poisson＇s ratio, anisotropic ratio,Kleinman parameters and Lame＇s coefficients were studied using the PBEsol to evaluate their importance in various types of engineering applications. The most prominent features of these compounds are their ductility, very high melting points, resistance to corrosion, and anisotropic nature.

关键词： Strongly correlated electron systems Rare-earth monoaurides mechanical properties Ab-initio calculation

Experimental and Numerical Evaluation of the Performance of Supersonic Two-Stage High-Velocity Oxy-Fuel Thermal Spray (Warm Spray) Gun

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Journal of Thermal Science 2011年第1期20卷 88-92页

作者： H.Katanoda H.morita m.Komatsu S.Kuroda department of mechanical Engineering Kagoshima University1-21-40 KorimotoKagoshima 890-0065Japan Hybrid materials Center National Institute for Materials Science1-2-1SengenTsukubaIbaraki 305-0047Japan

The water-cooled supersonic two-stage high-velocity oxy-fuel (HVOF) thermal spray gun was developed to make a coating of temperature-sensitive material,such as titanium,on a *** gun has a combustion chamber (CC) followed by a mixing chamber (mC),in which the combustion gas is mixed with the nitrogen gas at room *** mixed gas is accelerated to supersonic speed through a converging-diverging (C-d) nozzle followed by a straight passage called the *** paper proposes an experimental procedure to estimate the cooling rate of CC,mC and barrel ***,the mathematical model is presented to predict the pressure and temperature in the mC for the specific mass flow rates of fuel,oxygen and nitrogen by assuming chemical equilibrium with water-cooling in the CC and mC,and frozen flow with constant specific heat from stagnant condition to the throat in the CC and ***,the present mathematical model was validated by comparing the calculated and measured stagnant pressures of the CC of the two-stage HVOF gun.

关键词： Supersonic flow Two-stage HVOF thermal spray gun Warm spray

高支化含无机粒子的巯基硅氧烷溶胶的制备及结构表征

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高分子材料科学与工程 2006年第4期22卷 134-137页

作者：贺建芸 mark d.Soucek 北京化工大学高性能UV材料研究室北京100029 美国阿克隆大学聚合物科学与工程学院

用溶胶-凝胶法制备了一种新型的多功能巯基硅氧烷溶胶,其结构用1H-Nm R,FT-IR和m S进行了表征,巯基硅氧烷溶胶的无机粒子粒径大小与分布用小角度光散射仪(SALS)进行了测定。这种新型巯基硅氧烷溶胶能够提高改性亚麻籽油体系自由基聚合... 详细信息

用溶胶-凝胶法制备了一种新型的多功能巯基硅氧烷溶胶,其结构用1H-Nm R,FT-IR和m S进行了表征,巯基硅氧烷溶胶的无机粒子粒径大小与分布用小角度光散射仪(SALS)进行了测定。这种新型巯基硅氧烷溶胶能够提高改性亚麻籽油体系自由基聚合速率。

关键词：巯基硅氧烷溶胶溶胶-凝胶法高支化多官能有机/无机混杂改性亚麻籽油

A Heterogeneous Ensemble of Extreme Learning machines with Correntropy and Negative Correlation

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Tsinghua Science and Technology 2017年第6期22卷 691-701页

作者： Adnan O.m.Abuassba Yao Zhang Xiong Luo dezheng Zhang Wulamu Aziguli School of Computer and Communication Engineering University of Science and Technology Beijing(USTB)Beijing 100083China Beijing Key Laboratory of Knowledge Engineering for materials Science Beijing 100083China School of Engineering New York UniversityBrooklynNY 11201USA

The Extreme Learning machine（ELm） is an effective learning algorithm for a Single-Layer Feedforward Network（SLFN）. It performs well in managing some problems due to its fast learning speed. However, in practical applications, its performance might be affected by the noise in the training data. To tackle the noise issue, we propose a novel heterogeneous ensemble of ELms in this article. Specifically, the correntropy is used to achieve insensitive performance to outliers, while implementing Negative Correlation Learning（NCL） to enhance diversity among the ensemble. The proposed Heterogeneous Ensemble of ELms（HE2 Lm） for classification has different ELm algorithms including the Regularized ELm（RELm）, the Kernel ELm（KELm）, and the L2-norm-optimized ELm（ELmL2）. The ensemble is constructed by training a randomly selected ELm classifier on a subset of the training data selected through random resampling. Then, the class label of unseen data is predicted using a maximum weighted sum approach. After splitting the training data into subsets, the proposed HE2 Lm is tested through classification and regression tasks on real-world benchmark datasets and synthetic datasets. Hence, the simulation results show that compared with other algorithms, our proposed method can achieve higher prediction accuracy, better generalization, and less sensitivity to outliers.

关键词： Extreme Learning machine(ELm) ensemble classification correntropy negative correlation

A New Hybrid model for Segmentation of the Skin Lesion Based on Residual Attention U-Net

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Computers, materials & Continua 2023年第6期75卷 5177-5192页

作者： Saleh Naif Almuayqil Reham Arnous Noha Sakr magdy m.Fadel department of Information Systems College of Computer and Information SciencesJouf UniversitySakakaSaudi Arabia department of Communications and Electronics Delta Higher Institute for Engineering and Technology(DHIET)MansouraEgypt Computers Engineering and Control Systems department Faculty of EngineeringMansoura UniversityMansouraEgypt

Skin segmentation participates significantly in various biomedical applications,such as skin cancer identification and skin lesion *** paper presents a novel framework for segmenting the *** framework contains two main stages:The first stage is for removing different types of noises from the dermoscopic images,such as hair,speckle,and impulse noise,and the second stage is for segmentation of the dermoscopic images using an attention residual U-shaped Network(U-Net).The framework uses variational Autoencoders(VAEs)for removing the hair noises,the Generative Adversarial denoising Network(dGAN-Net),the denoising U-shaped U-Net(d-U-NET),and Batch Renormalization U-Net(Br-U-NET)for remov-ing the speckle noise,and the Laplacian Vector median Filter(mLVmF)for removing the impulse *** the second main stage,the residual attention u-net was used for *** framework achieves(35.11,31.26,27.01,and 26.16),(36.34,33.23,31.32,and 28.65),and(36.33,32.21,28.54,and 27.11)for removing hair,speckle,and impulse noise,respectively,based on Peak Signal Noise Ratio(PSNR)at the level of(0.1,0.25,0.5,and 0.75)of *** framework also achieves an accuracy of nearly 94.26 in the dice score in the process of segmentation before removing noise and 95.22 after removing different types of *** experiments have shown the efficiency of the used model in removing noise according to the structural similarity index measure(SSIm)and PSNR and in the segmentation process as well.

关键词： Skin tumor speckle noise impulse noise hair noise deep learning segmentation