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Chinese Physics Letters 2004年第6期21卷 1171-1174页

作者： M.Khalid K.M.Khan A.U.Qaisrani Q.N.malik DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan NuclearPhysicsDivision PakistanInstituteofNuclearScienceandTechnology(PINSTECH)P.O.NiloreIslamabadPakistan

We investigate the effect of the ballistic mechanism on the phase diagram using a square surface. While using this mechanism whenever an O2 molecule hits a randomly vacant selected site, the molecule breaks up into atomic form and then executes a ballistic flight. The paths of the two oxygen atoms are taken exactly to be opposite to each other, ***-parallel, and the ranges of the atoms are taken to be equal, *** may fly up to 1 or 1.414 or 2 of the atomic spacing from the site of impact. Four cases have been studied on the basis of the range of hot atoms. The range of the hot oxygen atoms executing a ballistic flight might be up to the first nearest neighbourhood (1 atomic spacing from the site of impact), the second nearest neighbourhood (1.414 atomic spacing from the site of impact), the third nearest neighbourhood (2 atomic spacing from the site of impact), known as cases a, b, and c, respectively, while for case d the range of the oxygen atoms executing the ballistic flight might be up to 1 atomic spacing or 1.414 atomic spacing or 2 atomic spacing from the site of impact. The steady reactive window is observed and the continuous transition disappears. As soon as the CO partial pressure departs from zero, the production of CO2 is observed, which clearly verifies the experimental observation.

关键词： Oxygen

Effect of Surface Roughness on Laser Induced Nonlinear Optical Properties of Annealed ZnO Thin Films

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Journal of Materials Science & Technology 2012年第6期28卷 506-511页

作者： Vinay Kumari Vinod Kumar Devendra Mohan Purnima B.P.malik R.M.Mehra Department of Physics BMIETSonepat 131001India Department of Physics DCRUSTMurthal 131027India Materials Science Group Inter University Accelerator CentreAruna Asaf Ali MargNew Delhi 110067India Department of Applied Physics GJUS&THisar 125001India School of Engineering and Technology Sharda UniversityGreater Noida 201306India

Variation of nonlinear optical properties with surface roughness of ZnO thin films deposited on coming glass substrates at different annealing temperature （TA） was reported. The films were characterized by X-ray diffraction （XRD）, UV-Vis-NIR transmission and single beam z-scan technique using second harmonics of Nd：YAG laser. Surface morphology of the samples was investigated by atomic force microscopy （AFM）. Surface roughness was found minimum （8.4 nm） for ZnO sample annealed at 450℃. The nonlinear optical properties （NLO） were found to be dependent on surface roughness and the highest value of third order nonlinear susceptibility （X（3）=4.3x 10-7 esu） was obtained for ZnO at TA 450℃.

关键词： ZnO films Sol-gel Annealing temperature Nonlinear optical properties Thirdorder nonlinear susceptibility z-scan

Review of sub-synchronous interaction in wind integrated power systems: classification, challenges, and mitigation techniques

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Protection and Control of Modern Power Systems 2023年第2期8卷 13-38页

作者： Neevatika Verma Narendra Kumar Saket Gupta Hasmat malik Fausto Pedro García Márquez Department of Electrical Engineering Delhi Technological UniversityDelhi 110042India Department of Electrical Power Engineering Faculty of Electrical EngineeringUniversiti Teknologi Malaysia(UTM)81310 JohorMalaysia Ingenium Research Group DepartmentUniversidad Castilla-La Mancha13071 Ciudad RealSpain Department of Electrical Engineering Graphic Era Deemed to be UniversityDehradun 248002India Instrumentation and Control Engineering Department Bharati Vidyapeeth’s College of EngineeringNew Delhi 110056India

Emerging sub-synchronous interactions(SSI)in wind-integrated power systems have added intense attention after numerous incidents in the US and China due to the involvement of series compensated transmission lines and power electronics *** phenomenon occurs when two power system elements exchange energy below the synchro-nous *** phenomenon related to wind power plants is one of the most significant challenges to main-taining stability,while SSI phenomenon in practical wind farms,which has been observed recently,has not yet been described on the source of conventional SSI *** paper first explains the traditional development of SSI and its classification as given by the IEEE,and then it proposes a classification of SSI according to the current research status,reviews several mitigation techniques and challenges,and discusses analysis techniques for *** paper also describes the effect of the active damping controllers,control scheme parameters,degree of series compensation,and various techniques used in wind power plants(WPPs).In particular,a supplementary damping controller with converter controllers in Doubly Fed Induction Generator based WPPs is briefly *** paper provides a real-istic viewpoint and a potential outlook for the readers to properly deal with SSI and its mitigation techniques,which can help power engineers for the planning,economical operation,and future expansion of sustainable development.

关键词： Damping controller Doubly fed induction generator(DFIG) Series compensations Sub-synchronous interactions(SSI) Sub-synchronous resonance(SSR)

Influence of quasispecies on virological responses and disease severity in patients with chronic hepatitis C

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World Journal of Gastroenterology 2008年第5期14卷 701-708页

作者： Deepak Kumar Abdul malik Mohammad Asim Anita Chakravarti Rakha H Das Premashis Kar Department of Medicine Department of Microbiology Maulana Azad Medical College New Delhi 110002 IndiaDeepak Comparative Genomics Unit Institute of Genomics and Integrative Biology Delhi University Campus Mall Road Delhi 110007 India Department of Microbiology Maulana Azad Medical College New Delhi 110002 IndiaDeepak Comparative Genomics Unit Institute of Genomics and Integrative Biology Delhi University Campus Mall Road Delhi 110007 India Department of Microbiology Maulana Azad Medical College New Delhi 110002 India

AIM:To elucidate the influence of quasispecies on virological response and disease severity in patients with chronic hepatitis C. METHODS:Forty seven patients with hepatitis C [32 with chronic active hepatitis (CAH), 9 with cirrhosis, and 6 with hepatocellular carcinoma (HCC)] were screened for the presence of quasispecies by single stranded conformational polymorphism (SSCP) analysis in the hypervariable region (HVR) and non-structural 5B (NS5B) viral genes of hepatitis C virus. The 41 patients excluding those with HCC were on therapy and followed up for a year with the determination of virological response and disease severity. Virus isolated from twenty three randomly selected patients (11 non-responders and 12 showing a sustained virological response) was sequenced for the assessment of mutations. RESULTS:The occurrence of quasispecies was proportionately higher in patients with HCC and cirrhosis than in those with CAH, revealing a significant correlation between the molecular evolution of quasispecies and the severity of disease in patients with hepatitis C. The occurrence of complex quasispecies has a significant association (P < 0.05) with the non-responders, and leads to persistence of infection. Significant differences (P < 0.05) in viral load (log10 IU/mL) were observed among patients infected with complex quasispecies (CQS), those infected with simple quasispecies (SQS) and those with no quasispecies (NQS), after 12 wk (CQS-5.2 ± 2.3, SQS-3.2 ± 1.9, NQS-2.8 ± 2.4) and 24 wk (CQS-3.9 ± 2.2, SQS-3.0 ± 2.2, NQS-2.1 ± 2.3) in the HVR region. However, a statistically significant difference (P < 0.05) was observed between the viral loads of patients infected with CQS and those infected with NQS in NS5B viral gene after 24 wk (CQS-3.9 ± 2.2, SQS-3.0 ± 2.2, and NQS-2.1 ± 2.3) and 48 wk (CQS-3.1 ± 2.7, SQS-2.3 ± 2.4, NQS-2.0 ± 2.3) of therapy. Disease severity was significantly associated with viral load during therapy. The strains isolated from non-responders sho

关键词： Hepatitis C virus Single-strand conformational polymorphism Quasispecies Virological response Interferon therapy

Prevalence and gene frequency of color vision impairments among children of six populations from North Indian region

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Genes & Diseases 2015年第2期2卷 211-218页

作者： Mohd Fareed malik Azeem Anwar Mohammad Afzal Human Genetics and Toxicology Laboratory Section of GeneticsDepartment of ZoologyFaculty of Life SciencesAligarh Muslim UniversityAligarh202002Uttar PradeshIndia Department of Molecular Genetics The Ohio State UniversityColumbusOHUSA

X-linked redegreen color blindness is the most widespread form of vision *** study aimed to determine the prevalence and gene frequencies of redegreen color vision impairments among children of six different human populations of Jammu province.A total of 1028 healthy subjects(6e15 years of age)were selected from five Muslim populations and the color vision impairments were determined using the Ishihara’s test of color *** gene frequency was calculated using HardyeWeinberg equilibrium *** prevalence of color vision deficiency(CVD)ranged from 5.26%to 11.36%among males and 0.00%e3.03%among females of six different *** gender based differences in the frequency of CVD was found to be statistically significant(pmalik and Syed populations,*** allele and genotype frequencies showed cogent differences among six *** population based assessment of CVDs help patients to follow adaptive strategies that could minimize the risks of the disease.

关键词： Allele frequency Color blindness Color vision deficiency Gene frequency Genotypes Human populations Public health Vision science

Feature Enhanced Stacked Auto Encoder for Diseases Detection in Brain MRI

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Computers, Materials & Continua 2023年第8期76卷 2551-2570页

作者： Umair Muneer Butt Rimsha Arif Sukumar Letchmunan Babur Hayat malik Muhammad Adil Butt School of Computer Sciences Universiti Sains MalaysiaPenang1180Malaysia Department of Computer Science and IT The University of ChenabGujrat50700Pakistan

The detection of brain disease is an essential issue in medical and research *** learning techniques have shown promising results in detecting and diagnosing brain diseases using magnetic resonance imaging(MRI)*** techniques involve training neural networks on large datasets of MRI images,allowing the networks to learn patterns and features indicative of different brain ***,several challenges and limitations still need to be addressed further to improve the accuracy and effectiveness of these *** paper implements a Feature Enhanced Stacked Auto Encoder(FESAE)model to detect brain *** standard stack auto encoder’s results are trivial and not robust enough to boost the system’s ***,the standard Stack Auto Encoder(SAE)is replaced with a Stacked Feature Enhanced Auto Encoder with a feature enhancement function to efficiently and effectively get non-trivial features with less activation energy froman *** proposed model consists of four ***,pre-processing is performed to remove noise,and the greyscale image is converted to Red,Green,and Blue(RGB)to enhance feature details for discriminative feature ***,feature Extraction is performed to extract significant features for classification using DiscreteWavelet Transform(DWT)and ***,classification is performed to classify MRI images into four major classes:Normal,Tumor,Brain Stroke,and Alzheimer’***,the FESAE model outperforms the state-of-theart,machine learning,and deep learning methods such as Artificial Neural Network(ANN),SAE,Random Forest(RF),and Logistic Regression(LR)by achieving a high accuracy of 98.61% on a dataset of 2000 MRI *** proposed model has significant potential for assisting radiologists in diagnosing brain diseases more accurately and improving patient outcomes.

关键词： Brain diseases deep learning feature enhanced stacked auto encoder stack auto encoder

Experimental Study of the Influence of Process Pressure and Gas Composition on GaAs Etching Characteristics in Cl_2/BCl_3-Based Inductively Coupled Plasma

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Plasma Science and Technology 2011年第2期13卷 223-229页

作者： D.S.RAWAL B.K.SEHGAL R.MURALIDHARAN H.K.malik Solid State Physics Laboratory PWAPA Laboratory Department of Physics Indian Institute of Technology Delhi

A study of Cl2/BCl3-based inductively coupled plasma （ICP） was conducted using thick photoresist mask for anisotropic etching of 50μm diameter holes in a GaAs wafer at a relatively high average etching rate for etching depths of more than 150μm. Plasma etch characteristics with ICP process pressure and the percentage of BCI3 were studied in greater detail at a constant ICP coil/bias power. The measured peak-to-peak voltage as a function of pressure was used to estimate the minimum energy of the ions bombarding the substrate. The process pressure was found to have a substantial influence on the energy of heavy ions. Various ion species in plasma showed minimum energy variation from 1.85 eV to 7.5 eV in the pressure range of 20 mTorr to 50 mTorr. The effect of pressure and the percentage of BCl3 on the etching rate and surface smoothness of the bottom surface of the etched hole were studied for a fixed total flow rate. The etching rate was found to decrease with the percentage of BCl3, whereas the addition of BCl3 resulted in anisotropic holes with a smooth veil free bottom surface at a pressure of 30 mTorr and 42% BC13. In addition, variation of the etching yield with pressure and etching depth were also investigated.

关键词： GaAs inductively coupled plasma etching ion energy etch yield

Aquila Optimization with Machine Learning-Based Anomaly Detection Technique in Cyber-Physical Systems

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Computer Systems Science & Engineering 2023年第8期46卷 2177-2194页

作者： A.Ramachandran K.Gayathri Ahmed Alkhayyat Rami Q.malik Department of Computer Science and Engineering University College of EngineeringPanruti607106India Department of Electronics and Communication Engineering University College of EngineeringPanruti607106India College of Technical Engineering The Islamic UniversityNajafIraq Medical Instrumentation Techniques Engineering Department Al-Mustaqbal University CollegeBabylonIraq

Cyber-physical system(CPS)is a concept that integrates every computer-driven system interacting closely with its physical ***-of-things(IoT)is a union of devices and technologies that provide universal interconnection mechanisms between the physical and digital *** the complexity level of the CPS increases,an adversary attack becomes possible in several *** security is a vital aspect of the CPS *** to the massive surge in the data size,the design of anomaly detection techniques becomes a challenging issue,and domain-specific knowledge can be applied to resolve *** article develops an Aquila Optimizer with Parameter Tuned Machine Learning Based Anomaly Detection(AOPTML-AD)technique in the CPS *** presented AOPTML-AD model intends to recognize and detect abnormal behaviour in the CPS *** presented AOPTML-AD framework initially pre-processes the network data by converting them into a compatible ***,the improved Aquila optimization algorithm-based feature selection(IAOA-FS)algorithm is designed to choose an optimal feature *** with that,the chimp optimization algorithm(ChOA)with an adaptive neuro-fuzzy inference system(ANFIS)model can be employed to recognise anomalies in the CPS *** ChOA is applied for optimal adjusting of the membership function(MF)indulged in the ANFIS *** performance validation of the AOPTML-AD algorithm is carried out using the benchmark *** extensive comparative study reported the better performance of the AOPTML-AD technique compared to recent models,with an accuracy of 99.37%.

关键词： Machine learning industry 4.0 cyber-physical systems anomaly detection aquila optimizer

Robust Image Watermarking Using LWT and Stochastic Gradient Firefly Algorithm

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Computers, Materials & Continua 2023年第4期75卷 393-407页

作者： Sachin Sharma Meena malik Chander Prabha Amal Al-Rasheed Mona Alduailij Sultan Almakdi Department of CSE Koneru Lakshmaiah Education FoundationGunturAndhra Pradesh522302India Deparmtent of CSE Chandigarh UniversityMohaliPunjab140413India Chitkara University Institute of Engineering and Technology Chitkara UniversityPunjab140401India College of Computer and Information Sciences Princess Nourah Bint Abdulrahman University84428Riyadh11671Saudi Arabia Department of Computer Science College of Computer Science and Information SystemsNajran UniversityNajran55461Saudi Arabia

Watermarking of digital images is required in diversified applicationsranging from medical imaging to commercial images used over the ***, the copyright information is embossed over the image in the form ofa logo at the corner or diagonal text in the background. However, this formof visible watermarking is not suitable for a large class of applications. In allsuch cases, a hidden watermark is embedded inside the original image as proofof ownership. A large number of techniques and algorithms are proposedby researchers for invisible watermarking. In this paper, we focus on issuesthat are critical for security aspects in the most common domains like digitalphotography copyrighting, online image stores, etc. The requirements of thisclass of application include robustness (resistance to attack), blindness (directextraction without original image), high embedding capacity, high Peak Signalto Noise Ratio (PSNR), and high Structural Similarity Matrix (SSIM). Mostof these requirements are conflicting, which means that an attempt to maximizeone requirement harms the other. In this paper, a blind type of imagewatermarking scheme is proposed using Lifting Wavelet Transform (LWT)as the baseline. Using this technique, custom binary watermarks in the formof a binary string can be embedded. Hu’s Invariant moments’ coefficientsare used as a key to extract the watermark. A Stochastic variant of theFirefly algorithm (FA) is used for the optimization of the technique. Undera prespecified size of embedding data, high PSNR and SSIM are obtainedusing the Stochastic Gradient variant of the Firefly technique. The simulationis done using Matrix Laboratory (MATLAB) tool and it is shown that theproposed technique outperforms the benchmark techniques of watermarkingconsidering PSNR and SSIM as quality metrics.

关键词： Image watermarking lifting wavelet transform discrete wavelet transform(DWT) firefly technique invariant moments

Synthesis and Single Crystal X-ray Studies of 3-(3,5-Bis(trifluoromethyl)phenyl) Quinoline and 3-(4-Fluoro-3-methylphenyl) Quinoline

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Chinese Journal of Structural Chemistry 2014年第1期33卷 90-96页

作者： malik Aman Ullah Muhammad Adeel Muhammad Nawaz Tahir Muhammad Raza Shah Irfan Ullah Department of Chemistry Gomal University Department of Physics University of Sargodha ICCBS HEJ Research Institute of ChemistryUniversity of Karachi

The title compounds 3-（3,5-bis（trifluoromethyl）phenyl）quinoline （1） and 3-（4- fluoro-3-methylphenyl）quinoline （2） were synthesized through Suzuki-Miyaura Cross coupling reaction of 3-bromoquinoloine with aryl boronic acids. The title compounds were characterized by single-crystal X-ray diffraction, 1H NMR, 13C NMR, El-MS, elemental analysis and IR. The crystals of 3-（3,5-bis（trifluoromethyl）phenyl）quinoline （C17H9F6N, Mr = 341.25） belongs to the monoclinic system, space group P21n, a = 12.3072（13）, b = 4.9378（6）, c = 24.493（2） A, V= 1473.1（3） A3, Z = 4, Dc = 1.539 Mg m-3, 2 - 0.71073A, μ = 0.144 mm^-1, F（000） = 688, the final R = 0.0715 and wR = 0.1873 for 1875 obserwed reflections with I 〉 2σ（I） and the crystal of 3-（4-fluoro-3- methylphenyl）quinoline （C16H12FN, Mr= 237.27） belongs to the orthorhombic system, space group Pca21, a = 23.794（2）, b = 3.9094（3）, c = 25.669（2） A, V = 2387.7（4） A3, Z = 8, D, = 1.320 Mg m-3, 2 = 0.71073 A, μ = 0.088 mm-1, F（000） = 992, the final R = 0.0534 and wR = 0.1188 for 2270 observed reflections with I 〉 2σ（I）.

关键词： 3-bromoquinoline crystal structure Pd(PPh3)3 boronic acid suzuki coupling