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Ergodic Capacity Evaluation of Multi-Hop Decode-and-Forward MIMO-OFDM Relaying Network

Computers, Materials & Continua 2021年第9期68卷 3133-3145页

作者： Latif Jan Mohammad Haseeb Zafar Abdul waheed Mahdi Zareei Faisal Alanazi Department of Electrical Engineering University of Engineering&TechnologyPeshawar25120Pakistan Department of Information Technology Hazara UniversityMansehra21120Pakistan Tecnologico de Monterrey School of Engineering and SciencesZapopan45201Mexico Department of Electrical Engineering Prince Sattam Bin Abdulaziz UniversityCollege of EngineeringAl Kharj16278Saudi Arabia

Spatial diversity plays a significant role in wireless communication systems,including the Fourth Generation(4G)and Fifth Generation(5G)systems,and it is expected to be a fundamental part of the future wireless communication systems as *** Multiple-Input Multiple-Output(MIMO)technology,which is included in the IEEE 802.16j standard,still holds the most crucial position in the 4G spectrum as it promises to improve the throughput,capacity,spectral,and energy efficiency of wireless communication systems in the *** makes MIMO a viable technology for delay constrained medical and health care *** paper presents an approximate closed-form expression of the ergodic capacity for the Decode-and-Forward(DF)protocol MIMO-Orthogonal Frequency Division Multiplexing(OFDM)relaying *** MIMO-OFDM is highly valuable for modern high-speed wireless communication systems,especially in the medical sciences,its performance degrades in multi-hop relay ***,in this paper,an approximate closed-form expression is derived for an end-to-end ergodic capacity of multi-hop DF MIMO-OFDM wireless communication system has been ***-Carlo simulations are conducted to verify the performance of the presented analysis regarding the capacity(bits/s/Hz)for different SNR-dB values for single,2×2,4×4,and multi-hop DF MIMOOFDM *** presented results provide useful insights for the research on the end-to-end ergodic capacity evaluation.

关键词： Multiple-input multiple-output system decode-and-forward protocol orthogonal frequency division multiplexing ergodic capacity

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A survey on trust based detection and isolation of malicious nodes in ad-hoc and sensor networks

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Frontiers of Computer Science 2015年第2期9卷 280-296页

作者： Adnan AHMED Kamalrulnizam ABU BAKAR Muhammad Ibrahim CHANNA Khalid HASEEB Abdul waheed KHAN Faculty of Computing Universiti Teknologi Malaysia Johor Bahru 81310 Malaysia Department of Information Technology Quaid-e-Awam University of Engineering Science and Technology Nawabshah 67450 Pakistan

Mobile ad-hoc networks （MANETs） and wireless sensor networks （WSNs） have gained remarkable apprecia- tion and technological development over the last few years. Despite ease of deployment, tremendous applications and significant advantages, security has always been a challeng- ing issue due to the nature of environments in which nodes operate. Nodes＇ physical capture, malicious or selfish behav- ior cannot be detected by traditional security schemes. Trust and reputation based approaches have gained global recog- nition in providing additional means of security for decision making in sensor and ad-hoc networks. This paper provides an extensive literature review of trust and reputation based models both in sensor and ad-hoc networks. Based on the mechanism of trust establishment, we categorize the state- of-the-art into two groups namely node-centric trust mod- els and system-centric trust models. Based on trust evidence, initialization, computation, propagation and weight assign- ments, we evaluate the efficacy of the existing schemes. Fi- nally, we conclude our discussion with identification of some unresolved issues in pursuit of trust and reputation manage- ment.

关键词： trust reputation wireless sensor network mo-bile ad-hoc networks routing node misbehavior

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Performance of Islamic and conventional stock indices:empirical evidence from an emerging economy

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Financial Innovation 2015年第1期1卷 229-245页

作者： Md Ejaz Rana waheed Akhter Center of Islamic Finance Department of Management SciencesCOMSATS Institute of Information TechnologyLahorePakistan

Background:This study aims to investigate the extent to which the conditional volatilities of both Shari’ah compliant stock and conventional stock are related to those of interest rate and exchange rate in the emerging economy of ***:We used KMI 30 and KSE 100 indices for Islamic and conventional stock for the period of July 2008 to November *** employed Generalized Autoregressive Conditional Heteroskedastic in the mean(GARCH-M)*** framework relaxes constancy assumption of classical linear regression(CLRM)model and allows exchange rate and interest rate volatility to evolve over *** GARCHM framework also reveals results about risk-return trade-off in the context of both Islamic and conventional stock ***:The findings show positive and statistically significant effect of interest rate volatility on KSE-100,whereas KMI-30 remains unaffected by the *** rate volatility is found to be significant for both conventional and Islamic *** relationship of risk coefficient(γ)and stocks returns,as expected,is positive and statistically significant for both KMI-30 and *** result is consistent with the theory of risk-return *** results of parametric t-test show significant difference between returns of both *** implies that Shari’ah compliant stock index(KMI-30)of Pakistan underperforms its conventional ***:By using different performance measures(Sharp ratio,Jensen alpha,Treynor ratio),this study also investigates the hypothesis that Islamic stock index has inferior performance compared with unscreened conventional counterparts due to availability of a smaller investment universe,increased monitoring costs,and limited diversification.

关键词： KMI-30 KSE-100 Index Shari’ah Exchange rate volatility Interest rate volatility Stock Performance etc

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Multiple rational rogue waves for higher dimensional nonlinear evolution equations via symbolic computation approach

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Journal of Ocean Engineering and Science 2023年第1期8卷 33-41页

作者： Saima arshed Nauman Raza Asma Rashid Butt Ahmad Javid J.F.Gómez-Aguilar Department of Mathematics University of the PunjabQuaid-e-Azam CampusLahorePakistan Department of Mathematics University of Engineering and TechnologyLahorePakistan School of Natural Sciences(SNS) National University of Sciences and Technology(NUST)Islamabad 44000Pakistan CONACyT-Tecnológico Nacional de México/CENIDET Interior Internado Palmira S/NCol.PalmiraCuernavaca Morelos C.P.62490México

The paper investigates the multiple rogue wave solutions associated with the generalized Hirota-Satsuma-Ito(HSI)equation and the newly proposed extended(3+1)-dimensional Jimbo-Miwa(JM)equation with the help of a symbolic computation *** incorporating a direct variable trans-formation and utilizing Hirota’s bilinear form,multiple rogue wave structures of different orders are ob-tained for both generalized HSI and JM *** obtained bilinear forms of the proposed equations successfully investigate the 1st,2nd and 3rd-order rogue *** constructed solutions are verified by inserting them into original *** computations are assisted with 3D graphs to analyze the propagation dynamics of these rogue *** properties of these waves are governed by different parameters that are discussed in details.

关键词： Generalized Hirota-Satsuma-Ito(HSI) equation The new extended(3+1)-dimensional Jimbo-Miwaequation Symbolic computation approach Bilinear form Rogue wave solutions

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Research on Error Compensation for Macro-micro Motion Ultra-precision 5-axis CNC Turn-milling Combined Machine Tool

Research on Error Compensation for Macro-micro Motion Ultra-...

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作者： waheed Elick Mia 天津职业技术师范大学

学位级别：硕士

在制造业中,精度被认为是一个非常重要的方面。精度对加工过程中的零件质量有巨大影响。目前从航空航天到电子行业,对超精密产品的需求很高,随后需要具有高定位分辨率的超精密机床,以满足亚微米精度要求。然而,几何误差会对机床轴运动... 详细信息

在制造业中,精度被认为是一个非常重要的方面。精度对加工过程中的零件质量有巨大影响。目前从航空航天到电子行业,对超精密产品的需求很高,随后需要具有高定位分辨率的超精密机床,以满足亚微米精度要求。然而,几何误差会对机床轴运动的定位精度产生负面影响。由于固有的几何误差和外部干扰的必然性,对这些误差的补偿是显著的。后来,精确检测这些补偿误差会产生时间,专业知识和成本相关的挑战,因此基于误差预测模型的实时误差补偿正在成为机器学习中一种有吸引力的方法,可以快速,稳健且低成本地最小化机床误差。基于对智能材料的研究和精确的误差检测方法,设计并测试了一种纳米分辨率定位压电陶瓷宏微运动平台硬件和控制系统。平台设计了纳米级运动微型载物台,以补偿微米级宏观运动误差。在x轴激光干涉测量误差检测实验和宏观误差数据库微观级补偿中,验证了在多轴运动控制器PMAC上运行的宏微运动超精密五轴车削铣削复杂机床的多体系统误差补偿模型作为轴位置的函数。补偿前后的平均最大定位和直线误差分别从35μm降低到0.006μm和3.5μm降低到0.45μm。采用R-studio中SVR程序代码实现的网格搜索和k-fold交叉验证方法,对实验数据进行训练和测试,采用高预测性、更好的泛化、补偿精度和鲁棒性的新型支持向量机回归算法进行响应预测。利用核技巧调优并得到最优参数后,补偿前的平均最大定位和直线度x轴运动误差预测为34.72μm和3.46μm,分别代表99.2%和88.5%的预测精度水平。基于预测精度置信水平,提出在PMAC模块中实现一种基于SVM误差预测的实时误差补偿模型。

关键词：支持向量机回归宏观-微观组合运动运动精度误差预测误差补偿

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Resource Allocation and Optimization in Device-to-Device Communication 5G Networks

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Computers, Materials & Continua 2021年第10期69卷 1201-1214页

作者： Fahad Ahmed Al-Zahrani Imran Khan Mahdi Zareei Asim Zeb Abdul waheed Computer Engineering Department Umm Al-Qura UniversityMecca24381Saudi Arabia Department of Electrical Engineering University of Engineering and Technology PeshawarP.O.B.814Pakistan Tecnologico de Monterrey School of Engineering and SciencesZapopan45201Mexico Department of Computer Science Abbottabad University of Science and TechnologyHavelian22500Pakistan Department of Information Technology Hazara University MansehraMansehra21120Pakistan School of Electrical and Computer Engineering Seoul National UniversitySeoul08826Korea

The next-generation wireless networks are expected to provide higher capacity,system throughput with improved energy *** of the key technologies,to meet the demand for high-rate transmission,is deviceto-device(D2D)communication which allows users who are close to communicating directly instead of transiting through base stations,and D2D communication users to share the cellular user chain under the control of the cellular *** a new generation of cellular network technology,D2D communication technology has the advantages of improving spectrum resource utilization and improving system throughput and has become one of the key technologies that have been widely concerned in the ***,due to the sharing of cellular network resources,D2D communication causes severe interference to existing cellular *** of the most important factors in D2D communication is the spectrum resources utilization and energy consumption which needs considerable attention from research *** address these issues,this paper proposes an efficient algorithm based on the idea of particle swarm *** main idea is to maximize the energy efficiency based on the overall link optimization of D2D user pairs by generating an allocation matrix of spectrum and *** D2D users are enabled to reuse multiple cellular user’s resources by enhancing their total energy efficiency based on the quality of service constraints and the modification of location and speed in particle *** constraint also provides feasibility to solve the original fractional programming *** results indicate that the proposed scheme effectively improved the energy efficiency and spectrum utilization as compared with other competing alternatives.

关键词： 5G networks D2D communication resource allocation

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Synthesis of Nanostructured Mg-Ni Alloy and Its Hydrogen Storage Properties

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Journal of Materials Science & Technology 2012年第5期28卷 401-406页

作者： N.A. Niaz I. Ahmad waheed S. Khan S. Tajammul Hussain Department of Physics COMSATS Institute of Information Technology Islamabad Pakistan Research Centre of Materials Science School of Materials Science and Engineering Beijing Institute of Technology National Centre for Physics Qaid-a-Azam University Islamabad Pakistan

Nanostructured Mg–Ni alloy with the particle size in the range of 40–50 nm was synthesized by the thermal decomposition of bipyridyl complexes of Mg and Ni metals at 773 K for 24 h under dry argon gas ambient. The as-prepared nano-alloy was characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM） for compositional and structural analysis. The alloy exhibited superior hydrogen absorption and desorption behavior with 3.2 wt% absorption within 1 min at 573 K and about 3 wt% desorption within 5–10 min at 573 K. This favorable behavior of Mg–Ni compound for the hydrogen storage is due to the specific nanostructure of the material. The low activation energy values and favorable thermodynamics indicate that the prepared Mg–Ni alloy is an attracting material for hydrogen storage applications.

关键词： Mg-Ni alloy Hydrogen storage Pressure-composition-temperature (P-C-T) measurements Transmission electron microscopy

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A Semi-Supervised Approach for Aspect Category Detection and Aspect Term Extraction from Opinionated Text

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Computers, Materials & Continua 2023年第10期77卷 115-137页

作者： Bishrul Haq Sher Muhammad Daudpota Ali Shariq Imran Zenun Kastrati waheed Noor Department of Computer Science Sukkur IBA UniversitySukkur65200Pakistan Department of Computer Science Norwegian University of Science and Technology(NTNU)Gjøvik2815Norway Department of Informatics Linnaeus UniversityVäxjö35195Sweden Department of Computer Science&IT University of BalochistanQuetta87300Pakistan

The Internet has become one of the significant sources for sharing information and expressing users’opinions about products and their interests with the associated *** is essential to learn about product reviews;however,to react to such reviews,extracting aspects of the entity to which these reviews belong is equally ***-based Sentiment Analysis(ABSA)refers to aspects extracted from an opinionated *** literature proposes different approaches for ABSA;however,most research is focused on supervised approaches,which require labeled datasets with manual sentiment polarity labeling and aspect *** study proposes a semisupervised approach with minimal human supervision to extract aspect terms by detecting the aspect ***,the study deals with two main sub-tasks in ABSA,named Aspect Category Detection(ACD)and Aspect Term Extraction(ATE).In the first sub-task,aspects categories are extracted using topic modeling and filtered by an oracle further,and it is fed to zero-shot learning as the prompts and the augmented *** predicted categories are the input to find similar phrases curated with extracting meaningful phrases(e.g.,Nouns,Proper Nouns,NER(Named Entity Recognition)entities)to detect the aspect *** study sets a baseline accuracy for two main sub-tasks in ABSA on the Multi-Aspect Multi-Sentiment(MAMS)dataset along with SemEval-2014 Task 4 subtask 1 to show that the proposed approach helps detect aspect terms via aspect categories.

关键词： Natural language processing sentiment analysis aspect-based sentiment analysis topic-modeling POS tagging zero-shot learning

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Prediction Flashover Voltage on Polluted Porcelain Insulator Using ANN

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Computers, Materials & Continua 2021年第9期68卷 3755-3771页

作者： Ali Salem Rahisham Abd-Rahman waheed Ghanem Samir Al-Gailani Salem Al-Ameri Faculty of Electrical and Electronic Engineering University Tun Hussein Onn MalaysiaJohor86400Malaysia Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia TerengganuKuala Terengganu21030Malaysia School of Electrical and Electronic Engineering Universiti Sains MalaysiaNibong Tebal14300Malaysia Department of Electrical and Electronics Engineering Faculty of EngineeringAl-Madinah International UniversityKuala Lumpur57100Malaysia

This paper aims to assess the effect of dry band location of contaminated porcelain insulators under various flashover voltages due to *** locations of dry bands are proposed to be tested under different severity of contamination artificially produce using salt deposit density(SDD)sprayed on an *** tests of polluted insulators under proposed scenarios have been *** flashover voltage of clean insulators has been identified as a reference value to analyze the effect of contamination distribution and its *** dry band dimension has been taken into consideration in experimental *** flashover voltage has been predicted using an artificial neural network(ANN)technique based on the laboratory test *** ANN approach is constructed with five input data(geometry the insulator and parameters of contamination)and flashover voltage as the output of the *** indicated that the pollution distribution based on the proposed scenario has a significant influence on the flashover voltage *** of the ANN model reveals that the relative error values between the experimental results and the prediction appeared to be within 5%.This indicates the significant efficiency of the ANN technique in predicting the flashover voltage insulator under test.

关键词： Insulator pollution distribution artificial neural network dry band

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A Safe and Reliable Routing Mechanism of LEO Satellite Based on SDN

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Computers, Materials & Continua 2020年第7期64卷 439-454页

作者： Chao Guo Juan Guo Chanjuan Yu Zhaobin Li Cheng Gong Abdul waheed Department of Electronics and Communication Engineering Beijing Electronic Science and Technology InstituteBeijing100070China Vocational and Technical College Guilin University of Electronic TechnologyBeihai536000China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China University of Management Technology Lahore55300Pakistan

Satellite networks have high requirements for security and data processing *** order to improve the reliability of the network,software-defined network(SDN)technology is introduced and a central controller is set in the *** to the characteristics of global perspective,control data separation,and centralized control of SDN,the idea of SDN is introduced to the design of the satellite network *** a result,satellite nodes are only responsible for data transmission,while the maintenance of the links and the calculation of routes are implemented by the *** the massive LEO satellite network based on SDN,a state evaluation decision routing mechanism is *** designed mechanism monitors the status of the entire network effectively and reduces the on-board load on the satellite *** best routing decision is made under the comprehensive consideration of the current and historical status of each inter-satellite link between Low Earth Orbit(LEO)satellite network *** calculation and storage requirements are controlled within a reasonable *** on the curve parameter transmission fuzzy encryption algorithm,a safe and reliable condition assessment decision routing mechanism(CADRM)is *** ensures that the personal information of the LEO satellite network can be transmitted safely and *** experimental simulation results show the improvement of network throughput,the reduction of packet loss rate and the enhancing of network reliability.

关键词： Route LEO satellite SDN state assessment inter-satellite link

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