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An Anti-overload Model for Openstack Based on Effective Dynamic Migration.

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An Anti-overload Model for Openstack Based on Effective Dyna...

作者： ammar Mohammed Al_Moalmi 湖南大学

学位级别：硕士

作为一种新兴技术,云计算对信息技术行业产生了巨大变革,并持续受到来自公共领域和私营领域的关注。随着这种技术的不断发展及广泛应用,保持其诸如服务质量(QoS)和服务等级协议(SLA)的性能是很重要的。这也是我们选择云计算提供商的一... 详细信息

作为一种新兴技术,云计算对信息技术行业产生了巨大变革,并持续受到来自公共领域和私营领域的关注。随着这种技术的不断发展及广泛应用,保持其诸如服务质量(QoS)和服务等级协议(SLA)的性能是很重要的。这也是我们选择云计算提供商的一个重要参考依据。虚拟机迁移是改善虚拟机过度整合的一种主要手段,其中过度整合可能会导致应用性能下降。本文提出一种支持基础设施即服务(IaaS)和可以避免物理机过载的动态在线迁移技术。这种技术有助于快速发展的、主流的开源云平台OpenStack性能的改善。通过对OpenStack的深入研究,其核心组件帮助我们对过量负载比例进行观察。观察发现,需要一种考虑开销的动态虚拟机迁移的技术来减少过量负载导致的问题并且可以适时提高Qos及SLA的性能。本文使用单指数平滑算法来估计物理服务器在下一阶段的负载。进一步,我们提出了一种有效的基于自适应阈值策略的分布式策略,并且该策略适合易变的工作集环境。分布在本地主机上的算法可以有效地进行检测并防止过度负载,然后使用阈值策略选择合适的虚拟机来保持低负载。此外,提出了一种不同以往的运行在控制节点的算法,该算法可以有效地将虚拟机分配到负载最小的目标物理机上。这个工作有助于Openstack云平台提供包括管理及资源分发方面的改进,并符合可扩展管理目标。本方案的实现包括：分布式算法,负载获取组件及监控组件。试验结果表明我们的系统可以在合适的时候避免过载,并且仿真结果表明我们的方法在减少SLA违反及降低虚拟机迁移次数上面能够取得很好的效果。

关键词：云计算虚拟化 OpenStack 在线迁移

Protoscolicidal and immunomodulatory activity of Ziziphora tenuior extract and its fractions

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Asian Pacific Journal of Tropical Medicine 2016年第11期9卷 1040-1046页

作者： Mojtaba Shahnazi Abbas Azadmehr ammar Andalibian Reza Hajiaghaee Mehrzad Saraei Mahmood Alipour Department of Parasitology Qazvin University of Medical Sciences Cellular&Molecular Research Institute Qazvin University of Medical Sciences Department of Immunology Babol University of Medical Sciences Department of Pharmacognosy& Pharmaceutics Department of Medicinal Plants Research Center Institute of Medicinal Plants ACECR Department of Social Medicine Qazvin University of Medical Sciences

Objective:To evaluate the scolicidal and immunomodulatory effect of the Ziziphora tenuior(***) extract and its ***:Protoscolices were treated with six concentrations(3,5,10,25,50,and 100 mg/mL) of *** extract and its fractions(ethanol,petroleum ether,ethyl acetate and chloroform) in periods of 10,20,30,40,50 and 60 minutes,and viability of protoscolices was evaluated using the 1.0%*** examine the immunomodulatory effects of Ziziphora and its fractions on macrophage cells,the non-toxic concentration of extract and different fractions determined by MTT assay,and the Griess reaction was used to measure the level of nitrite as an indicator of nitric oxide by the macrophage cells in 10,100 and 200 μg/mL in 24 hours at 37 ℃.Results:In this study,the *** extract at 10 mg/mL concentration was able to kill all protoscolices during 20 *** increasing the concentration to 25 mg/mL,the scolicidal time reduced to 10 *** the effect of different fractions of ***,the ethanolic fraction showed the highest scolicidal *** extract demonstrated an inhibitory effect on the activity of macrophages and reduced nitric oxide *** the petroleum ether and ethanolic fractions of the extract reduced nitric oxide production,nevertheless,this effect was only significant at 10 and 100 ug/mL concentrations(P<0.05).Conclusion:The *** extract and its fractions were effective against protoscolices yet the effect of total extract was *** findings indicates that the extract and its ethanolic and petroleum ether fractions could have anti-inflammatory properties.

关键词： Hydatid cyst Protoscolicidal Ziziphora tenuior Immunomodulatory Macrophage Nitric oxide Fraction

An Optimized Algorithm for D2D-MIMO 5G Wireless Networks

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Computers, Materials & Continua 2021年第9期68卷 3029-3044页

作者： Shahid Bashir Imran Khan Fahd NAl-Wesabi Nadhem Nemri ammar Zahary Quang Ngoc Nguyen 无 Department of Business Studies Namal UniversityPakistan Department of Electrical Engineering University of Engineering and Technology PeshawarPakistan Department of Computer Science King Khalid UniversityMuhayel AseerKSA Faculty of Computer and IT Sana’a UniversitySana’aYemen Department of Communications and Computer Engineering Faculty of Science and Engineering Waseda University Shinjuku-kuTokyo169-0051Japan

The device-to-device(D2D)networking technology is extended to the conventional cellular network to boost the communication efficiency of the entire network,forming a heterogeneous 5G and beyond(B5G)communication network.D2D communication in a cellular cell will boost the efficiency of the spectrum,increase the ability of the device,and reduce the communication burden of base stations through the sharing of approved cell resources,causing serious interference as *** device-to-device(D2D)networking technology is extended to the conventional cellular network to boost the communication efficiency of the entire network,forming a heterogeneous 5G communication network.D2D communication in a cellular cell will boost the efficiency of the spectrum,increase the ability of the device,and reduce the communication burden of base stations through the sharing of approved cell resources,causing serious interference as *** paper proposes an efficient algorithm to minimize interference,based on the parity of the number of antennas,to resolve this *** primary concept is to generate the cellular connection precoding matrix by minimizing the power of interference from the base station to non-targeted *** through the criterion of maximum SINR,the interference suppression matrix of the cellular connection is ***,by removing intra-interference through linear interference alignment,the maximum degree of freedom is *** results of the simulation show that the proposed algorithm efficiently increases the performance of the spectrum,decreases interference,improves the degrees of freedom and energy efficiency compared to current algorithms.

关键词： 5G and beyond(B5G)networks device-to-device heterogeneous interference multiple-input and multiple-output

An Optimized Algorithm for Resource Allocation for D2D in Heterogeneous Networks

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Computers, Materials & Continua 2022年第2期70卷 2923-2936页

作者： Abdul Kadir Hamid Fahd N.Al-Wesabi Nadhem Nemri ammar Zahary Imran Khan Department of Electrical&Computer Engineering University of SharjahSharjahUnited Arab Emirates Department of Computer Science King Khalid UniversityMuhayel AseerKSA Faculty of Computer and IT Sana’a UniversitySanaaYemen Department of Information Systems King Khalid UniversityMayahel AseerKSA Department of Electrical Engineering University of Engineering and TechnologyPeshawarPaki

With the emergence of 5G mobile multimedia services,end users’demand for high-speed,low-latency mobile communication network access is *** them,the device-to-device(D2D)communication is one of the considerable *** D2D communication,the data does not need to be relayed and forwarded by the base station,but under the control of the base station,a direct local link is allowed between two adjacent mobile *** flexible communicationmode reduces the processing bottlenecks and coverage blind spots of the base station,and can be widely used in dense user communication scenarios such as heterogeneous ultra-dense wireless *** of the important factors which affects the quality-of-service(QoS)of D2D communications is co-channel *** order to solve this problem of co-channel interference,this paper proposes a graph coloring based *** main idea is to utilize the weighted priority of spectrum resources and enables multiple D2D users to reuse the single cellular user *** proposed algorithm also provides simpler power *** heterogeneous pattern of interference is determined using different types of interferences and UE and the priority of color is *** results show that the proposed algorithm effectively reduced the co-channel interference,power consumption and improved the system throughput as compared with existing algorithms.

关键词： 5G device-to-device communication wireless networks spectrum

Identification of suitable sites for rainwater harvesting structures in arid and semi-arid regions:A review

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International Soil and Water Conservation Research 2016年第2期4卷 108-120页

作者： ammar Adham Michel Riksen Mohamed Ouessar Coen Ritsema Wageningen University Soil Physics and Land Management Group476700 AA WageningenThe Netherlands Institut des Régions Arides Route de Djorf km 22.54119 MedenineTunisia University of Anbar RamadiIraq

Harvested rainwater is an alternative source of water in arid and semi-arid regions(ASARs)around the *** researchers have developed and applied various methodologies and criteria to identify suitable sites and techniques for rainwater harvesting(RWH).Determining the best method or guidelines for site selection,however,is *** main objective of this study was to define a general method for selecting suitable RWH sites in ASARs by assembling an inventory of the main methods and criteria developed during the last three *** categorised and compared four main methodologies of site selection from 48 studies published in scientific journals,reports of international organisations,or sources of information obtained from *** then identified three main sets of criteria for selecting RWH locations and the main characteristics of the most common RWH techniques used in *** methods were diverse,ranging from those based only on biophysical criteria to more integrated approaches including socio-economic criteria,especially after *** most important criteria for the selection of suitable sites for RWH were slope,land use/cover,soil type,rainfall,distance to settlements/streams,and *** success rate of RWH projects tended to increase when these criteria were considered,but an objective evaluation of these selection methods is still *** studies now select RHW sites using geographic information systems in combination with hydrological models and multi-criteria analysis.

关键词： Arid and semi-arid regions RWH Suitability Multi-criteria GIS Modelling

Research on Off-Line Arabic Text Recognition

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Research on Off-Line Arabic Text Recognition

作者： ammar Mohammed Ali Al-Tameemi 哈尔滨工程大学

学位级别：硕士

在过去的40年里，人类阅读的机器仿真是很重要的研究方向。由于阿拉伯文字的复杂性，对阿拉伯文字自动识别的研究很少见。随着拉丁文、中文和日文在光学文本识别上的成功，光学识别阿拉伯文也重新得以大量研究。到目前为止，虽然有些这... 详细信息

在过去的40年里，人类阅读的机器仿真是很重要的研究方向。由于阿拉伯文字的复杂性，对阿拉伯文字自动识别的研究很少见。随着拉丁文、中文和日文在光学文本识别上的成功，光学识别阿拉伯文也重新得以大量研究。到目前为止，虽然有些这方面研究的报告，但还需要大量深入的研究。在本文中，提出了一套用于阿拉伯文字结构和几何特征的提取方法。本系统重点运用了支持向量机（Support Vector Machines）作为模式识别的工具。假设每个阿拉伯字符的字形都是独立的类而忽略分割字符的特征。本系统主要分为三部分。第一部分是预处理，进行字符图像二值化，线性分割和单词分割。分割后的单词输入到第二部分--特征提取。提取的特征包括20个纵向滑动窗口特性的总和，纵向投影点密度的4个极大值和4个极小值，字符重心，连接部分的个数，角和重点的位置以及字符影像的平均值。最后一部分是分类，采用了具有一对多功能的多级支持向量机。最后还针对打印和手写阿拉伯字符对上述的识别系统进行评估。打印字符选用Andalus, Arial, Simplified Arabic, Tahoma和Traditional Arabic等五个字体，进行了四组实验。第一组实验分别用三个具有42个特性的数据集进行所用字体的检测，识别率分别为97.344%,88.727%和88.582%。与之对应，第二组实验对所有字体的单组特性进行检测，每组不同特性识别率分别为95.287%,90.446%和80.690%。第三组实验用15组不同的数据集对不同字体的不同组特性进行检测，识别率均在97%以上且最高识别率为98.743%。第四组实验用手写字符数据集对手写字符进行检测，识别率为94.884%。

关键词：滑动窗曲率本地极值连接部分支持向量机

Design and Simulation of Solar Panel Cleaning System of Dust

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Design and Simulation of Solar Panel Cleaning System of Dust

作者： ammar （MOHAMMAD NOUR EDDIN） GHAZI YACOUB（阿迪）大连海事大学

学位级别：硕士

Solar energy is the most abundant source of energy for all the forms of life on the planet *** is also the basic source for all the sources of energy except nuclear *** panel systems are being installed all over the world now more than *** energy crisis is leading countries to develop more policies on the energy sector,especially creating incentives for renewable energies so that the production would slowly shift towards more environmentally sustainable *** in view the protection of natural resources,the power generation from the solar photovoltaic system is increasing day by day to meet the energy demand *** are constraints of the availability of space for ground-mounted solar PV system for large *** some countries,water bodies;such as lakes,ports,shores,and oceans;are being utilized to install a solar PV system to reduce land *** floating systems using plastics have been developed to install a solar panel on *** accumulation on solar photovoltaic modules reduces light transmission from the outer surfaces to the solar cells reducing photon absorption and thus contributing to performance reduction of PV *** regions such as the Middle East where dust is prevalent and rainfall is scarce,remedial measures are needed to reduce such impacts.1-Based on particle adhesion theory and fluid mechanics,the adhesion mechanics model and dust force model of dust particles in the air are established,and the dust is analyzed in combination with the physical parameters of the dust on the surface of the actual photovoltaic *** adhesion in the three cleaning modes,the size of the force,and the relationship between the compressed air flow required for dust removal and the radius and adhesion of the dust *** results show that the required velocity range of the compressed air dust is between 5～80 m/s,and the cleaning velocity is inversely proportional to the dust particle radius.2-Next a study

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The prevalence,characteristics and outcome of seizure in tuberculous meningitis

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Acta Epileptologica 2020年第1期2卷 1-9页

作者： ammar Taha Abdullah Abdulaziz Jinmei Li Dong Zhou Department of Neurology West China HospitalSichuan University37 Guo Xue Xiang stChengdu 610041China. Faculty of Brain Sciences UCL Queen Square Institute of NeurologyLondon WC1N 3BGUK.

Seizures are a common finding in patients with tuberculous meningitis(TBM),and associate with four times increased risk of death and neurological disability,especially in *** has been reported that brain inflammation,diffuse neuronal injury,and reactive gliosis may all contribute to the pathogenesis of seizures in *** seizure onset may be associated with meningeal irritation and cerebral oedema;while,the late seizures are usually due to infarction,hydrocephalus,tuberculoma and paradoxical ***,recurrent uncontrolled seizures can evolve to status epileptics resulting in an increased risk of chronic epilepsy and poor ***,this review aimed to assess the frequency of seizures in patients with TBM,and discuss the etiologies,mechanisms,and characteristics of seizures in ***,we have searched the literature to identify the prognostic factors for chronic epilepsy after TBM.

关键词： Seizure Tuberculous meningitis Neuronal injury Epilepsy

Molybdenum sulfide/graphene-carbon nanotube nanocomposite material for electrocatalytic applications in hydrogen evolution reactions

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Nano Research 2016年第3期9卷 837-848页

作者： Majid Khan ammar Bin Yousaf Mingming Chen Chengsha Wei Xibo Wu Ningdong Huang Zemin Qi Liangbin Li National Synchrotron Radiation Laboratory and School of Nuclear Science and Technology CAS Key Laboratory of Soft Matter Chemistry University of Science and Technology of China Hefei 230029 China Department of Computer Science and IT Sarhad University of Science and Information Technology Peshawar 25000 Pakistan Hefei National Laboratory for Physical Sciences at Microscale School of Chemistry and Materials Science University of Science and Technology of China Hefei 230026 China

We report a three-dimensional hierarchical ternary hybrid composite of molybdenum disulfide （MoS2）, reduced graphene oxide （GO）, and carbon nano- tubes （CNTs） prepared by a two-step process. Firstly, reduced GO-CNT composites with three-dimensional microstructuresare synthesized by hydrothermal treatment of an aqueous dispersion of GO and CNTs to form a composite structure via π-π interactions. Then, MoS2 nanoparticles are hydrothermally grown on the surfaces of the GO-CNT composite. This ternary composite shows superior electrocatalytic activity and stability in the hydrogen evolution reaction, with a low onset potential of only 35 mV, a Tafel slope of -38 ***-1 and an apparent exchange current density of 74.25 ***-2. The superior hydrogen evolution activity stemmed from the synergistic effect of MoS2 with its electrocatalytically active edge-sites and excellent electrical coupling to the underlying graphene and CNT network.

关键词： 3D nanostructure MoS2 graphene carbon nanotubes hydrogen evolutionreaction