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Corrosion Resistance of AZ91 Magnesium Alloy after Laser Remelting Treatment

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Journal of Wuhan University of Technology(Materials Science) 2016年第5期31卷 1075-1080页

作者： STRZELECKA Monika IWASZKO Jozef malik Marcin A Czestochowa University of Technology 42-200 Czestochowa Poland

The main objective of the study was the modification of the surface layer of magnesium alloy by the COlaser. The studied material was the commercial AZ91 magnesium alloy. The effectiveness of the alternations caused by the remelting process was verified on the basis of microscopic observation and corrosion investigations, i e, recording of potentiodynamic polarization curves, electrochemical noise measurements and hydrogen evolution rate measurements. For the adopted range of the treatment parameters, favourable changes were observed in the surface layer such as the refinement of structure and more uniform arrangement of individual phases. As a consequence of those favourable structural changes the improvement of the corrosion resistance of the alloy was achieved in comparison to its non-remelted equivalent. For the treated material corrosion rates expressed as corrosion current densities were at least three times lower than the appropriate values for the untreated alloy comparing them for the same period of samples immersion in the test solution. The obtained results have confirmed the effectiveness of the applied surface treatment resulting in favourable changes in the structure and corrosion properties of the AZ91 magnesium alloy.

关键词： magnesium alloy CO_2 laser surface layer modification corrosion

Compressed H₃S: Fits to the Empirical H_c2(T) Data and a Discussion of the Meissner Effect

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World Journal of Condensed Matter Physics 2023年第4期13卷 111-127页

作者： Gulshan Prakash malik Vijaya Shankar Varma Gurugram India Theory Group School of Environmental Sciences Jawaharlal Nehru University New Delhi India Department of Physics and Astrophysics University of Delhi Delhi India

Based on μ-, T- and H-dependent pairing and number equations and the premise that μ(T) is predominantly the cause of the variation of the upper critical field Hc2(T), where μ, T and H denote the chemical potential, temperature and the applied field, respectively, we provide in this paper fits to the empirical Hc2(T) data of H3S reported by Mozaffari, et al. (2019) and deal with the issue of whether or not H3S exhibits the Meissner effect. Employing a variant of the template given by Dogan and Cohen (2021), we examine in detail the results of Hirsch and Marsiglio (2022) who have claimed that H3S does not exhibit the Meissner effect and Minkov, et al. (2023) who have claimed that it does. We are thus led to suggest that monitoring the chemical potential (equivalently, the number density of Cooper pairs Ns at T = Tc) should shed new light on the issue being addressed.

关键词： Compressed H3S Upper and Lower Critical Fields Chemical Potential Generalized Pairing and Number Equations Coherence Length Penetration Depth Meissner Effect

Behavior of Anisotropic Compact Stars in f(R,∅) Gravity

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Communications in Theoretical Physics 2019年第5期71卷 599-609页

作者： M.Farasat Shamir Adnan malik Department of Sciences and Humanities National University of Computer and Emerging Sciences

The aim of this paper is to investigate modified f(R, ?) theory of gravity, where R and ? represent the Ricci scalar and scalar potential respectively. Specifically, we take the spherically symmetric spacetime to discuss the possible emergence of compact stars. We study the physical behavior of compact stars by considering 4 U 1820-30, SAX J1808-3658 and Her X1, which are three popular models of compact stars. The graphical analysis of energy density, radial pressure, tangential pressure, energy conditions as well as stability of compact stars has been shown. It is concluded that behavior of these three stars is usual for f(R, ?) gravity models with some specific choices of model parameters.

关键词： f(R,∅) gravity spherically symmetric spacetime compact stars Klein-Gordon equation

An Innovative Approach Utilizing Binary-View Transformer for Speech Recognition Task

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Computers, Materials & Continua 2022年第9期72卷 5547-5562页

作者： Muhammad Babar Kamal Arfat Ahmad Khan Faizan Ahmed Khan malik Muhammad Ali Shahid Chitapong Wechtaisong Muhammad Daud Kamal Muhammad Junaid Ali Peerapong Uthansakul COMSATS University Islamabad Islamabad Campus45550Pakistan Suranaree University of Technology Nakhon Ratchasima30000Thailand COMSATS University Islamabad Lahore Campus54000Pakistan COMSATS University Islamabad Vehari Campus61100Pakistan National University of Sciences&Technology Islamabad45550Pakistan Virtual University of Pakistan Islamabad Campus45550Pakistan

The deep learning advancements have greatly improved the performance of speech recognition systems,and most recent systems are based on the Recurrent Neural Network(RNN).Overall,the RNN works fine with the small sequence data,but suffers from the gradient vanishing problem in case of large *** transformer networks have neutralized this issue and have shown state-of-the-art results on sequential or speech-related ***,in speech recognition,the input audio is converted into an image using Mel-spectrogram to illustrate frequencies and *** image is classified by the machine learning mechanism to generate a classification ***,the audio frequency in the image has low resolution and causing inaccurate *** paper presents a novel end-to-end binary view transformer-based architecture for speech recognition to cope with the frequency resolution ***,the input audio signal is transformed into a 2D image using ***,the modified universal transformers utilize the multi-head attention to derive contextual information and derive different speech-related ***,a feedforward neural network is also deployed for *** proposed system has generated robust results on Google’s speech command dataset with an accuracy of 95.16%and with minimal *** binary-view transformer eradicates the eventuality of the over-fitting problem by deploying a multiview mechanism to diversify the input data,and multi-head attention captures multiple contexts from the data’s feature map.

关键词： Convolution neural network multi-head attention multi-view RNN self-attention speech recognition transformer

Reprogramming cells with synthetic proteins

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Asian Journal of Andrology 2015年第3期17卷 394-402页

作者： Xiaoxiao Yang Vikas malik Ralf Jauch Genome Regulation Laboratory Guangzhou Institutes of Biomedicine and Health Chinese Academy of Sciences 190 Kai Yuan Avenue Science Park Guangzhou China

Conversion of one cell type into another cell type by forcibly expressing specific cocktails of transcription factors （TFs） has demonstrated that cell fates are not fixed and that cellular differentiation can be a two-way street with many intersections. These experiments also illustrated the sweeping potential of TFs to ＂read＂ genetically hardwired regulatory information even in cells where they are not normally expressed and to access and open up tightly packed chromatin to execute gene expression programs. Cellular reprogramming enables the modeling of diseases in a dish, to test the efficacy and toxicity of drugs in patient-derived cells and ultimately, could enable cell-based therapies to cure degenerative diseases. Yet, producing terminally differentiated cells that fully resemble their in vivo counterparts in sufficient quantities is still an unmet clinical need. While efforts are being made to reprogram cells nongeneticaUy by using *** molecules, defined TF cocktails still dominate reprogramming protocols. Therefore; the optimization of TFs by protein engineering has emerged as a strategy to enhance reprogramming to produce functional, stable and safe cells for regenerative biomedicine. Engineering approaches focused on Oct4, MyoD, Sox17, Nanog and Mef2c and range from chimeric TFs with added transactivation domains, designer transcription activator-like effectors to activate endogenous TFs to reprogramming TFs with rationally engineered DNA recognition principles. Possibly, applying the complete toolkit of protein design to cellular reprogramming can help to remove the hurdles that, thus far, impeded the clinical use of cells derived from reprogramming technologies.

关键词： cellular reprogramming protein design protein engineering synthetic transcription factors transactivation

Reduced bit low power VLSI architectures for motion estimation

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Journal of Systems Engineering and Electronics 2013年第3期24卷 382-399页

作者： Shahrukh Agha Shahid Khan Shahzad malik Raja Riaz Department of Electrical Engineering COMSATS Institute of Information Technology

Low power and real time very large scale integration （VLSI） architectures of motion estimation （ME） algorithms for mobile devices and applications are presented. The power reduction is achieved by devising a novel correction recovery mechanism based on algorithms which allow the use of reduced bit sum of absolute difference （RBSAD） metric for calculating matching error and conversion to full resolution sum of absolute difference （SAD） metric whenever necessary. Parallel and pipelined architectures for high throughput of full search ME corresponding to both the full resolution SAD and the generalized RBSAD algorithm are synthe- sized using Xilinx Synthesis Tools （XST）, where the ME designs based on reduced bit （RB） algorithms demonstrate the reduction in power consumption up to 45% and/or the reduction in area up to 38%.

关键词： motion estimation (ME) very large scale integration (VLSI) reduced bit sum of absolute difference (RBSAD).

Exact solutions of MHD second Stokes flow of generalized Burgers fluid

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Applied Mathematics and Mechanics(English Edition) 2015年第2期36卷 211-224页

作者： M.KHAN R.malik A.ANJUM Department of Mathematics Quaid-i-Azam University

This work concerns with the exact solutions of magnetohydrodynamic（MHD）flow of generalized Burgers fluid describing the second Stokes problem. The modified Darcy law is taken into account. The related velocity distribution and shear stress are expressed as a combination of steady-state and transient solutions computed by means of integral transformations. The effects of various parameters on the flow field are investigated. The MHD flow results in reduction of velocity distribution and associated thickness of the boundary layer.

关键词： generalized Burgers fluid magnetohydrodynamic(MHD) flow porous medium exact solution

Effect of processing on bioaccessibility and bioavailability of bioactive compounds in coffee beans

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Food Bioscience 2022年第2期46卷 1-13页

作者： Hanjing Wu Jingyu Gu Amrit BK malik A.Nawaz Colin J.Barrow Frank R.Dunshea Hafiz A.R.Suleria School of Agriculture and Food Faculty of Veterinary and Agricultural SciencesThe University of MelbourneParkville3010VICAustralia Commonwealth Scientific and Industrial Research Organisation(CSIRO) Agriculture and Food671 Sneydes RoadPrivate Bag 16WerribeeVictoria3030Australia Centre for Chemistry and Biotechnology School of Life and Environmental SciencesDeakin UniversityWaurn PondsVIC3217Australia Faculty of Biological Sciences The University of LeedsLeedsLS29JTUK

Coffee is one of the most prevalent and functional beverages around world owing to its rich content of bioactive *** compounds and alkaloids are two primary groups of bioactive compounds in coffee beans,which have been proven healthy benefits in regular and suitable daily *** have been recognized as protective factors,especially phenolic compounds,to perform high antioxidant capacities and potential to relieve the occurrence of chronic diseases and partial *** content and composition of bioactive and anti-nutritional compounds in coffee beans can be mainly influenced by variety,processing and storage *** cultivar of Arabica coffee beans(***)exhibits lower content of phenolic compounds but similar anti-nutritional substances with the comparison to Robusta(***).Comparing to green coffee beans,reasonable roasting contributes to the improvement of phenolic content and its total antioxidant activity because of the liberation of bound phenolic compounds and the generation of novel compounds with antioxidant *** intensive roasting will not only decrease the number of bioactive compounds within the coffee beans but also stimulate the generation of endogenous anti-nutritional compounds,which consequently reduce the coffee nutritional *** fluctuations of moisture content during storage would be the primary reason of the changes in the content of bioactive *** compounds in coffee beans perform outstanding bioaccessibility but relatively lower absorption efficiency because of the combination with other *** roasting would improve the bioavailability of bioactive *** interaction between phenolic compounds and proteins would also influence the bioavailability and bioactivity of bioactive compounds and final nutritional value after consumption.

关键词： Coffee beans Phenolic compounds Alkaloids Anti-nutritional compounds Roasting Bioavailability

A Correlation Visual Analytics System for Air Quality

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Chinese Journal of Electronics 2018年第5期27卷 920-926页

作者： DU Yi Abish malik ZHOU Lianke ZHOU Yuanchun Department of Big Data Technology and Application Development Computer Network Information CenterChinese Academy of Sciences

A visual analytics system is proposed to reveal the lead/lag correlation when air pollution is detected. In this system, an Overview + Detail approach is utilized for analyzing the correlation of air quality under both the spatial and temporal dimensions and different spatial-temporal scales. An annular container is proposed to preserve the context spatial information while the zoom level of the map changes. Based on the annular container, several analysis techniques such as STL decomposition view and correlation algorithm are integrated.

关键词： Spatial-temporal visualization Time series visualization Correlation analysis Air pollution