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Secrecy sum-rate analysis of massive MIMO systems under dual-threat attacks using normalization methods

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Digital Communications and Networks 2019年第4期5卷 237-244页

作者： Kishan Neupane rami J.Haddad Dept.of Electrical and Computer Eng.Georgia Southern UniversityStatesboroGA30460USA

Massive Multiple Input Multiple Output(MIMO)has been considered as an emerging technology to enhance the spectral and energy efficiency for the upcoming wireless communication *** paper derives a closedform approximation for the Ergodic Achievable Secrecy Sum-Rate(EASSR)by considering the joint impact of eavesdroppers and *** widely used linear precoding techniques,Zero-Forcing(ZF)and Maximum Ratio Transmission(MRT),were used in conjunction with matrix and vector normalization to analyze the secrecy ***-form expressions are used to explain how the secrecy performance is affected when using the ZF and MRT precoding in the eavesdropping and jamming attack *** also analyze and compare the performances of different combinations of normalization method and precoding technique in various *** the analytical expressions and simulation results,we observe that the vector and matrix normalization perform better for the ZF precoding than for the MRT precoding in high Signal-to-Noise Ratio(SNR)***,in low SNR,the MRT with matrix normalization outperforms the ZF with vector normalization regardless of the number of users in the ***,we observe that the MRT fails to serve more than two users in high SNR *** results obtained from Monte Carlo simulation are used to corroborate the accuracy of the asymptotic secrecy analysis.

关键词： Massive MIMO Linear precoding Normalization methods Secrecy analysis

An Effective Memory Analysis for Malware Detection and Classification

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Computers, Materials & Continua 2021年第5期67卷 2301-2320页

作者： rami Sihwail Khairuddin Omar Khairul Akram Zainol Ariffin Department of Information Science&Technology Universiti Kebangsaan MalaysiaSelangor43600Malaysia

The study of malware behaviors,over the last years,has received tremendous attention from researchers for the purpose of reducing malware *** of the investigating experiments are performed using either static analysis or behavior ***,recent studies have shown that both analyses are vulnerable to modern malware files that use several techniques to avoid analysis and ***,extracted features could be meaningless and a distraction for malware ***,the volatile memory can expose useful information about malware behaviors and *** addition,memory analysis is capable of detecting unconventional malware,such as in-memory and fileless ***,memory features have not been fully utilized ***,this work aims to present a new malware detection and classification approach that extracts memory-based features from memory images using memory forensic *** extracted features can expose the malware’s real behaviors,such as interacting with the operating system,DLL and process injection,communicating with command and control site,and requesting higher privileges to perform specific *** also applied feature engineering and converted the features to binary vectors before training and testing the *** experiments show that the proposed approach has a high classification accuracy rate of 98.5%and a false positive rate as low as 1.24%using the SVM *** efficiency of the approach has been evaluated by comparing it with other related ***,a new memory-based dataset consisting of 2502 malware files and 966 benign samples forming 8898 features and belonging to six memory types has been created and published online for research purposes.

关键词： Cybersecurity feature selection machine learning malware dataset malware detection memory analysis memory features

DILECTRIC AND THERMAL PROPERTIES OF PEO DOPED WITH CADIMIUM CHLORIDE SALT

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Chinese Journal of Polymer Science 2012年第2期30卷 143-151页

作者： Jibril Al-Hawarin Ayman S.Ayesh rami A.Abdel-Rahem Chemistry Department College of ScienceAl Hussein Bin Talal UniversityMaanJordan Physics Department College of ScienceKing Faisal UniversityAl-AhssaKingdom of Saudi Arabia Chemistry Department College of ScienceKing Faisal UniversityAl-AhssaKingdom of Saudi Arabia

The main aim of this research is to investigate the effect of salt concentration on the dielectric properties （AC （CrAC）, permittivity （d）, dielectric loss （d＇）, and dielectric relaxation process） and melting behavior of polyethylene oxide （PEO）/CdC12 complexes. The dielectric study was carried out over a frequency range 10-335 kHz and a temperature range 25--45~C. The AC conductivity, permittivity and dielectric loss of the PEO/CdC12 complexes increase with increasing salt concentration and temperature. Also, it was found that the addition of CdC12 salt to PEO host reduced the melting temperature of PEO host. Dielectric results reveal that the relaxation process of these complexes is due to viscoelastic relaxation or non-Debye relaxation at room temperature. Additionally, it was found that relaxation behavior remained viscoelastic at different temperatures and salt concentrations.

关键词： Polyethylene oxide CdC12 salt Dielectric properties Dielectric relaxation Relaxation process Thermalproperties.

Expeditious method for the synthesis of novel 2,3,5,6-tetrahydrobenzo[g] [1,3,5]oxadiazocine-4-thiones linked with isoxazole

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Chinese Chemical Letters 2008年第12期19卷 1415-1418页

作者： E.Rajanarendar A.Siva rami Reddy M.Srinivas Department of Chemistry Kakatiya UniversityWarangal 506009India

Synthesis of novel 3-aryl-5-（3,5-dimethylisoxazol-4-yl）-2,3,5,6-tetrahydrobenzo[g][1,3,5],oxadiazocine-4-thiones 5 has been accomplished from 3,5-dimethylisoxazol-4-amine 1 by condensation with salicylaldehydes, followed by reduction, treatment with aryl isothiocyanates and subsequent smooth ring closure via acetal formation in the presence of formaldehyde.

关键词： Isoxazolyl-2,3,5,6-tetrahydrobenzo[g]oxadiazocine-4-thiones Ring closure New methodology

Thermoviscoelastic Analysis of Stress in Composite Structures Micro-to-Structural Approach

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Transactions of Nanjing University of Aeronautics and Astronautics 2014年第2期31卷 191-194页

作者： Liri Shemesh Jacob Aboudi rami Eliasi David Livshits Department of Mechanical Engineering Tel Aviv University Israel Israel Military Industries Ltd. Israel

Manufacturing of composite materials is usually accompanied with residual *** stresses should be evaluated and *** this end,a micromechanical model for periodic material whose temperature dependent constituents behave as thermorheologically complex materials(TCM)has been *** model,referred as the high fidelity generalized method of cells(HFGMC),takes into account the detailed interaction between the fiber and resin,their volume ratios,the fibers distribution and their *** model is linked,in conjunction with a special UMAT subroutine,to the ABAQUS finite element code for prediction of the response of thermoviscoelastic composite structures during cool down *** present investigation shows the effect of the cool down rate on the residual stress developed in the composite cylindrical structures.

关键词： cool down thermorheologically complex materials(TCM) epoxy high fidelity generalized method of cells(HFGMC) finite element method(FEM)

Dark energy from logarithmically modified gravity and deformed Coleman-Weinberg potential

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Research in Astronomy and Astrophysics 2011年第7期11卷 759-766页

作者： Ahmad rami El-Nabulsi Department of Nuclear and Energy Engineering Cheju National University College of Mathematics and Information Sciences Neijiang Normal University

Recent astrophysical measurements strongly suggest the existence of a missing energy component dubbed dark energy that is responsible for the current accelerated expansion of the universe.A new class of modified gravity theory is introduced which yields a universe accelerating in time and dominated by dark *** new modified gravity model constructed here concurrently includes a Gauss-Bonnet invariant term,barotropic fluid with a time-dependent equation of state parameter,a Coleman-Weinberg（CW） potential-like expression V（φ） =ξφm lnφn and a new Einstein-Hilbert term f（R,φ） =E（φ） R which depends on both the scalar curvature and the scalar fieldφthrough a generic logarithmic function E（φ） =lnφ.Here m and n take different values from the standard CW potential andξis a real parameter. It was shown that the presence of these terms provides many useful features which are discussed in some detail.

关键词： dark energy—gravitation—equation of state

Hop-by-hop Content Distribution with Network Coding in Multihop Wireless Networks

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Digital Communications and Networks 2017年第1期3卷 47-54页

作者： rami Halloush Hang Liu Lijun Dong Mingquan Wu Hayder Radha Department of Telecommunications Engineering Yarmouk University Irbid Jordan Department of Electrical Engineering and Cor~uter Sci The Catholic University of America Washington DC USA Huawei Research Center Santa Clara CA USA Huawei Technologies USA Inc. Bridgewater N J USA Department of Electrical and Computer Engineering Michigan State University East Lansing MI USA

The predominant use of today＇s networks is content access and distribution. Network Coding （NC） is an innovative technique that has potential to improve the efficiency of multicast content distribution over multihop Wireless Mesh Networks （WMNs） by allowing intermediate Forwarding Nodes （FNs） to encode and then forward data packets. Practical protocols are needed to realize the benefits of the NC technique. However, the existing NC-based multicast protocols cannot accurately determine the minimum number of coded packets that a FN should send in order to ensure successful data delivery to the destinations, so that many redundant packets are injected into the network, leading to performance degradation. In this paper, we propose HopCaster, a novel reliable multicast protocol that incorporates network coding with hop-by-hop transport. HopCaster completely eliminates the need for estimating the number of coded packets to be transmitted by a FN, and avoids redundant packet transmissions. It also effectively addresses the challenges of heterogeneous mulficast receivers. Moreover, a cross-layer multicast rate adaptation mechanism is proposed, which enables HopCaster to optimize multicast throughput by dynamically adjusting wireless transmission rate based on the changes in the receiver population and channel conditions during the course of mulficasting a coded data chunk. Our evaluations show that HopCaster significantly outperforms the existing NC-based multicast protocols.

关键词： Content distributionNetwork coding MulticastHop-by-hop transportRate adaptation

The effect of methylseleninic acid on paclitaxel efficacy in A2780 ovarian cancer cells

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Journal of Nanjing Medical University 2009年第2期23卷 111-116页

作者： Qiaoli Zhang rami G. Azrak Maternal and Child Health Center the First Affiliated Hospital of Xi' an Jiaotong University Xi' an 710061 China Department of Cancer Biology Roswell Park Cancer Institute Buffalo New York 14263 U.S.A.

Objective：The role of methylseleninic acid （MSeA）, a selenium compound, has been documented in cancer chemoprevention. However, the therapeutic effect of MSeA in combination with paclitaxel, a chemotherapeutic agent used to treat ovarian cancer, is unknown. In this study, we investigated the effect of combination treatment of MSeA and paclitaxel against ovarian cancer cells. Methods：Ovarian cancer cells（A2780） were treated with different concentrations of MSeA, paclitaxel alone or in combination. The individual and combined concentrations of drugs that achieved certain cells growth/death were determined using a sulforhodamine B（SRB） assay. Drug effects on cell viability were further confirmed using floating cell count and trypan blue exclusion assay. The mean Values ± standard deviation were calculated and compared between treatment groups using unpaired t test. Results： The concentration of paclitaxel alone that inhibited 50% of cell growth（IC50） was 0.5 μmol/L. This concentration increased to 1.2 μmol/L when paclitaxel was given in sequential combination with MSeA. The number of dead cells after the combination treatment did not show a significance increase when compared with drug alone. Conclusion：Pretreatment with MSeA did not enhance the paclitaxel effect against A2780 ovarian cancer cells.

关键词： methylseleninic acid paclitaxel ovarian cancer

Dysphagia: Thinking outside the box

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World Journal of Gastroenterology 2017年第38期23卷 6942-6951页

作者： Hamish Philpott Mayur Garg Dunya Tomic Smrithya Balasubramanian rami Sweis Department of Gastroenterology Eastern Health Clinical School Monash University University College London

Dysphagia is a common symptom that is important to recognise and appropriately manage, given that causes include life threatening oesophageal neoplasia, oropharyngeal dysfunction, the risk of aspiration, as well as chronic disabling gastroesophageal reflux(GORD). The predominant causes of dysphagia varies between cohorts depending on the interplay between genetic predisposition and environmental risk factors, and is changing with time. Currently in white Caucasian societies adopting a western lifestyle, obesity is common and thus associated gastroesophageal reflux disease is increasingly diagnosed. Similarly, food allergies are increasing in the west, and eosinophilic oesophagitis is increasingly found as a cause. Other regions where cigarette smoking is still prevalent, or where access to medical care and antisecretory agents such as proton pump inhibitors are less available, benign oesophageal peptic strictures, Barrett's oesophagus, adeno-as well as squamous cell carcinoma are endemic. The evaluation should consider the severity of symptoms, as well as the pretest probability of a given condition. In young white Caucasian males who are atopic or describe heartburn, eosinophilic esophagitis and gastroesophageal reflux disease will predominate and a proton pump inhibitor could be commenced prior to further investigation. Upper gastrointestinal endoscopy remains a valid first line investigation for patients with suspected oesophageal dysphagia. Barium swallow is particularly useful for oropharyngeal dysphagia, and oesophageal manometry mandatory to diagnose motility disorders.

关键词： Dysphagia Oesophagus Eosinophilic Manometry Gastroesophageal reflux Aspiration Food bolus impaction