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A Compact Flexible Circularly Polarized Implantable Antenna for Biotelemetry Applications

Computers, Materials & Continua 2022年第11期73卷 2457-2472页

作者： Sarosh Ahmad Shakir Ullah adnan ghaffar Daniel Segovia Vargas Department of Signal Theory and Communications Universidad Carlos III de MadridMadrid28911Spain Department of Telecommunication Engineering University of Engineering and TechnologyPeshawar25120Pakistan Department of Electrical and Electronic Engineering Auckland University of TechnologyAuckland1010New Zealand

With the help of in-body antennas,the wireless communication among the implantable medical devices(IMDs)and exterior monitoring equipment,the telemetry system has brought us many ***,a very thin-profile circularly polarized(CP)in-body antenna,functioning in ISM band at 2.45 GHz,is proposed.A tapered coplanar waveguide(CPW)method is used to excite the *** radiator contains a pentagonal shape with five horizontal slits inside to obtain a circular polarization behavior.A bendable Roger Duroid RT5880 material(εr=2.2,tanδ=0.0009)with a typical 0.25 mm-thickness is used as a *** proposed antenna has a total volume of 21×13×0.25 *** antenna covers up a bandwidth of 2.38 to 2.53 GHz(150 MHz)in vacuum,while in skin tissue it covers 1.56 to 2.72 GHz(1.16 GHz)and in the muscle tissue covers 2.16 to 3.17 GHz(1.01 GHz).GHz).The flexion analysis in the x and y axes was also performed in simulation as the proposed antenna works with a wider bandwidth in the skin and muscle *** simulation and the curved antenna measurements turned out to be in good *** impedance bandwidth of−10 dB and the axis ratio bandwidth of 3 dB(AR)are measured on the skin and imitative gel of the pig at 27.78%and 35.5%,13.5%and 4.9%,respectively,at a frequency of 2.45 *** simulations revealed that the specific absorption rate(SAR)in the skin is 0.634 and 0.914 W/kg in muscle on *** recommended SAR values are below the limits set by the federal communications commission(FCC).Finally,the proposed low-profile implantable antenna has achieved very compact size,flexibility,lower SAR values,high gain,higher impedance and axis ratio bandwidths in the skin and muscle tissues of the human *** antenna is smaller in size and a good applicant for application in medical implants.

关键词： ISM band implantable antenna biotelemetry circularly polarized flexible antenna

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基于MSP430的半导体器件测试设备的设计

基于MSP430的半导体器件测试设备的设计

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作者： adnan ghaffar 兰州交通大学

学位级别：硕士

功率半导体器件是电子技术的主要组成部分。自1956年晶闸管发明以来,制造生产出大量的半导体器件。功率半导体器件在日常生活中应用十分广泛,是电子设备中的必要元件。目前,在电子工业中主要的半导体器件有BJT、MOSFET、IGBT以及IGCT,... 详细信息

功率半导体器件是电子技术的主要组成部分。自1956年晶闸管发明以来,制造生产出大量的半导体器件。功率半导体器件在日常生活中应用十分广泛,是电子设备中的必要元件。目前,在电子工业中主要的半导体器件有BJT、MOSFET、IGBT以及IGCT,主要应用于高压、快速切换、高频等。相对于硅材料,碳化硅材料使得半导体器件的性能得到较大提高。半导体器件是每个电子设备不可或缺的部分,大部分电子设备的异常是由半导体器件的损坏或者其他原因造成的。如果是半导体器件的原因,则需要对其进行更换。由于电子设备种类繁多,如果知道半导体器件的型号,则容易进行更换,如果没有半导体器件的任何数据,则难于更换。基于这一问题,设计了一种半导体测试设备。本文使用两个开关对半导体器件进行测量:一个开关被用于分离微控制器的上拉电阻。我们可以关闭所述销的使用另一个开关的输出。输出取决于另一个开关,也可用于控制上拉电阻。这两个开关的状态不能在同一时间工作,会交替处于工作状态。所述半导体器件的三个测试终端具有三个引脚的微控制器中的一个连接。每个检测终端的状态可以改变为输出,并以同样的方式将其与电源以及接地端连接。以另一种方式,它们与680K、470K或通过地面、电源连接,此方法被用于正引脚。同一标准用于测试终端的负状态。第三端子销也被称为测试引脚,可以是开放式或连接在同一正、负引脚上.它由两部分组成:硬件部分和软件部分。在硬件部分,我们设计了一块PCB板。选用Altium Designer软件设计电路图和PCB.首先,论文中所画示意图为本次课题的研究项目,并确认了所有的模拟连接,完成所有连接后进行PCB设计。在PCB设计中,在不影响其它部件连接方式的基础上,并避免热、电磁的影响,在项目中采用16×2液晶显示器。液晶屏被用于***等电子设备中,不但经济且易于编程、显示动画等。16×2的液晶屏可以每行显示16个字符,并可双行显示。在两行中,每个字符是由5x7像素矩阵组成。论文中设计了大量的电路图和PCB库。市场上有各种微处理器,我们选用低功耗的MSP430F132,它有混合信号处理能力、16位处理器、16位地址和数据总线;32KHz CPU、多种外设由于DCO快速重启功能等。该设备可由9V电池运行。论文中使用了两个电压调节器。由于除MSP430,所有部件需要在5V电压下工作,因此其中一个调节器(LM7805)用于将9V电压转换为5V;另一个调节器(AM1117)被用于将5V电压转换为3V。MSP430的工作电压超过3V时会损坏。焊接工作是在实验室完成的,PCB的大小为800mmX500mm,硬件的详细信息见后面章节。在软件部分,主要是对MCU的编程和调试。以IAR Embedded Workbench为开发环境,采用C语言编程,使用MSP-FET430UIF作为PC接口,其仿真功能强大,可以快速启动MSP430微控制器并应用于程序的开发。软件中的USB调试工具被用于MSP430的编程,其调试系统具有JTAG接口、间谍碧-Wire协议的辅助,通过它可以抹去闪存和程序新代码。由于MSP430的兼容性问题,不能使用USB接口。在这两部分内容完成之后,我们进行了一些功能性测试以保证PCB板没有任何问题.这些测试包括I/O功能的测试、振荡器测试和外设测试。对于I/O功能的测试,我们通过发送一些简单的代码检查所有的引脚。这一系列的测试是检查所有引脚的连接性,并确保在PCB板上的两个或更多的引脚之间没有交叉连接。在振荡器测试中,代码的写入用于启用和禁用外部晶体振荡器的使用。在外围测试中,代码用于激活设备以及测试。这些代码来自于MSP430的代码示例。经过测试后该板可以进行测量了。它可以自动识别NPN和PNP晶体管、计算电流放大系数和基极-发射极电压阈值并将其显示于LCD显示屏。采用同样的方式,它还可以识别N型和P型MOSFET,计算栅阈值电压和栅容量。关断电流约为20nA。

关键词： PNP三极管 NPN三极管 N-Channel MOSFET P-Channel MOSFET MSP430 JTAG PCB(印刷电路板) LCD

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巴基斯坦留学生在兰州跨文化适应状况调查——以兰州地区大学为例

巴基斯坦留学生在兰州跨文化适应状况调查——以兰州地区大学为例

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作者： adnan ghaffar（安恒心）西北师范大学

学位级别：硕士

近年来,随着中国经济的快速发展以及中国悠久历史文化的文化魅力,越来越多的留学生来到中国学习。在高等教育国际化趋势的影响下,留学生对于中国的认知也更加全面。这些认知有利于他们更好地融入中国的社会文化环境中。其中,巴基斯坦作... 详细信息

近年来,随着中国经济的快速发展以及中国悠久历史文化的文化魅力,越来越多的留学生来到中国学习。在高等教育国际化趋势的影响下,留学生对于中国的认知也更加全面。这些认知有利于他们更好地融入中国的社会文化环境中。其中,巴基斯坦作为中国最坚定的盟友和最欢迎的国家之一,巴基斯坦在华留学生人数逐年增加。因此,加强巴基斯坦留学生在中国的跨文化适应研究意义重大。兰州大学是兰州地区最有名的国家重点大学。其校园中的生活学习环境跟兰州地区本地的生活环境普遍相似。最重要的是兰州大学拥有足够数量的巴基斯坦留学生,可以满足本次巴基斯坦留学生在兰州跨文化适应调查研究的研究样本需求。本文将通过分析国内外跨文化适应的研究现状,以兰州大学中的巴基斯坦留学生作为研究对象,采用问卷调查和个人访谈的形式调查留学生存在的跨文化适应问题,并从社会环境方面、人际交往方面、心态思想方面、学习娱乐方面给巴基斯坦留学生提出一些建议。研究结果发现,巴基斯坦留学生在中国留学学习期间确实存在跨文化适应问题,这些问题产生的主要原因是来华初期不了解中国的文化和自身零基础的汉语水平。但是随着留学生留学时间的增长、汉语能力的提升以及跟中国朋友的频繁接触,绝大多数巴基斯坦留学生可以适应中国的文化环境并且愿意继续在中国生活。

关键词：跨文化适应兰州大学巴基斯坦留学生

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Edge Coloring of Graphs with Applications in Coding Theory

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China Communications 2021年第1期18卷 181-195页

作者： ghaffar Raeisi Mohammad Gholami Department of Mathematical Sciences Shahrekord UniversityShahrekordP.O.Box 115Iran

In this paper,a new type of edge coloring of graphs together with an algorithm for such an edge coloring is presented to construct some columnweight three low-density parity-check(LDPC)codes whose Tanner graphs are free of *** kind of edge coloring is applied on some well-known classes of graphs such as complete graphs and complete bipartite graphs to generate some column-weight 3 LDPC codes having flexibility in terms of code length and ***,the constructed(3;k)-regular codes with regularities k=4;5;:::;22 have lengths n=12;20;26,35;48;57;70;88;104;117;140;155;176;204;228;247;280;301;330;having minimum block length compared to the best known similar codes in the *** addition to linear complexity of generating such parity-check matrices,they can be considered as the base matrices of some quasi-cyclic(QC)LDPC codes with maximum achievable girth 18,which inherit the low-complexity encoder implementations of QC-LDPC *** results show that the QC-LDPC codes with large girth lifted from the constructed base matrices have good performances and outperform random codes,progressive edge growth LDPC codes,some finite fields and group rings based QC-LDPC codes and also have a close competition to the standard IEEE 802.16e(WiMAX)code.

关键词： low-density parity-check code edge coloring Quasi-cyclic LDPC code girth AWGN channel

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High-frequency field intensity along focal point of a long metallic parabolic reflector coated by a magnetized plasma layer using oblique incidence

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Chinese Optics Letters 2015年第9期13卷 14-19页

作者： Abdul ghaffar Majeed A.S.Alkanhal Department of Electrical Engineering King Saud University Department of Physics University of Agriculture

Theoretical analysis of the electromagnetic field distribution in the focal region of a long metallic parabolic reflector that has its surface covered with a magnetized plasma layer is derived. The incident wave is considered to be with a general oblique incidence for both parallel and perpendicular polarizations. The electromagnetic field intensity expressions along the focal region are obtained accurately using Maslov＇s method. The effects of plasma thickness on the reflected and transmitted field distributions are investigated. The effects of other physi- cal parameters such as the angle of incidence and the plasma and cyclotron frequencies on the transmitted field- intensity distribution along the focal region are also studied. The results obtained by Maslov＇s method and Kirchhoff＇s approximation are found to be in a good agreement.

关键词： High-frequency field intensity along focal point of a long metallic parabolic reflector coated by a magnetized plasma layer using oblique incidence TT Ei

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Preparation and characterization of eco-friendly poly(p-phenylenediamine) and its composite with chitosan for removal of copper ions from aqueous solutions

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Transactions of Nonferrous Metals Society of China 2015年第11期25卷 3808-3819页

作者： N.A.ABDELWAHAB E.A.AL-ASHKAR M.A.ABD EL-ghaffar Polymers and Pigments Department National Research Centre Spectroscopy Department Physics Division National Research Centre

Poly(p-phenylenediamine)/chitosan (PPPDA/Chi) composite was prepared by in situ chemical oxidative polymerization of p-phenylenediamine (PPPDA) into chitosan (Chi) using ammonium persulphate (APS) as an oxidant. PPPDA and PPPDA/Chi composite were characterized by FT-IR spectra and SEM before and after copper loading. In batch adsorption method, the maximum removal of copper was experienced when 1 g/L of PPPDA and PPPDA/Chi composite dosages were used at pH 5.0 for PPPDA and 6.0 for PPPDA/Chi composite for 360 min for both sorbents. PPPDA showed adsorption capacity qemax of 650 mg/g whereas its composite achieved qemax of 573 mg/g. The experimental data correlate well with the Freundlich isotherm equation and the pseudo-second order kinetic model. The Cu(II), loaded PPPDA and its composite can be efficiently reused for as many as four cycles. The Cu(II)-loaded sorbents showed high antibacterial efficiency against Gram-positive and Gram-negative bacteria than their unloaded forms.

关键词： copper removal adsorption poly(p-phenylenediamine)/chitosan composite kinetics isotherms

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A Micro Structure POF Relative Humidity Sensor Modified With Agarose Based on Surface Plasmon Resonance and Evanescent Wave Loss

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Photonic Sensors 2021年第4期11卷 392-401页

作者： Yanjun HU Abdul ghaffar Yulong HOU Wenyi LIU Fei LI Jun WANG Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051China

A novel high sensitivity relative humidity(RH)sensor was proposed by using micro structure plastic optical fiber(POF)based on the surface plasmon resonance(SPR)effect and the evanescent wave(EW)*** micro structure was fabricated on the POF and coated with a gold layer and agarose,adopting the sputtering and dip-coating *** construction effects on the attenuation of power caused by the SPR effect and the EW loss were used to perform RH *** agarose9s different refractive indexes(RIs)caused fluctuations in the transmission power when the humidity *** demonstrated experimental results showed that the proposed sensor achieved a linear response from 20%RH to 80%RH with a high sensitivity of 0.595μW/%.The proposed sensor had the advantages of fast response and ***,the temperature dependence and the repeatability test of the sensor were also performed.

关键词： SPR evanescent wave loss agarose RH sensor

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康复卫生政策和系统研究对加强卫生系统中康复服务的重要性:呼吁采取行动并加速开展

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中国康复 2024年第4期39卷 251-253页

作者： Walter R.Frontera Wouter DeGroote Abdul ghaffar 康复卫生政策和系统研究小组 WHO康复培训与研究合作中心(武汉) 不详

具体机构及作者名单如下:美国物理医学与康复杂志(WRF);世界卫生组织康复计划(WDG);世界卫生组织卫生政策和系统研究联盟(WAG);康复卫生政策和系统研究小组(合作期刊主编按字母顺序排列):Iben Axen,DC,博士(脊椎按摩疗法和手法治疗)、Mu... 详细信息

具体机构及作者名单如下:美国物理医学与康复杂志(WRF);世界卫生组织康复计划(WDG);世界卫生组织卫生政策和系统研究联盟(WAG);康复卫生政策和系统研究小组(合作期刊主编按字母顺序排列):Iben Axen,DC,博士(脊椎按摩疗法和手法治疗)、Muhammad Ehab Azim,DPT,MS-NMPT(基础大学康复科学杂志)、Linamara Battistella,医学博士、哲学博士(Acta Fisiatrica)、克里斯蒂安·博格,医学博士、哲学博士(康复医学杂志)、Ines Campos,医学博士、理学硕士(葡萄牙物理与康复医学杂志)、罗德里戈·卡斯特罗,医学博士(Revista Columbiana de Medicina Físicay Rehabilitación),Joaquim Chaler,MD,Ph.D(Rehabilitación),Leighton Chan,MD,MPH(物理医学与康复档案室)。

关键词：卫生政策物理医学卫生系统康复计划哲学博士按摩疗法卡斯特罗作者名单

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Adsorption of Diethyl Phthalate Onto Carbon Nanotubes

Adsorption of Diethyl Phthalate Onto Carbon Nanotubes

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作者： Abdul ghaffar 昆明理工大学

学位级别：硕士

The existence of different organic chemicals is common in industrial effluents and environments. The persistent organic chemicals （POPs） are the well-known organics that are amongst the unsafe and dangerous chemicals, because they have adverse effect to human health. These organics may be found in the fog, in atmosphere, in precipitation, in groundwater, surface water and soil. These toxic chemicals could be spread through living organisms and food chain and interact with other contamination. All together, the result is critical damage of natural equilibriums, thus, interaction of organics with prospective adsorbents can influence the environmental behavior and fate. Sorption characteristics and bio-toxicity are the leading focuses in contaminant behavior studies, largely because these two processes are ubiquitous in all environmental media. However, in the past few years, different results were reported in literature depending upon the experimental conditions, concluding both increased and decreased sorption. Adsorption of di-ethyl phthalate （DEP）, a selected chemical from different phthalic acid esters （PAEs） by different multi-wallled carbon nanotubes （MWCNTs） were conducted under different water chemical conditions to investigate the influence of thermodynamics in combination with site-sorption energy distribution and pH *** nanotubes have been extensively studied as a potential material to be used in a variety of applications because of their specific and tunable physical and chemical properties. The fast growth in industrial applications and production of CNTs, however, has also lifted serious concerns over their potential impacts on living organisms due to the evidence of their toxicity. The toxicities of CNTs mainly come from the toxic substances adsorbed on them rather than their own harmful natures. Once organic compounds are strongly adsorbed on CNTs, the fate, transport and environmental behavior of organic contaminants are changed. It is u

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Ontogenetic changes in feeding and food preferences of the dog conch Laevistrombus canarium Linnaeus 1758 (Mollusca： Gastropoda) from Merambong shoal, Malaysia

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Chinese Journal of Oceanology and Limnology 2017年第5期35卷 1230-1238页

作者： HUSNA Wan Nurul Wan Hassan MAZLAN Abd ghaffar COB Zaidi Che School of Environmental and Natural Resource Science Faculty of Science and Technology Universiti Kebangsaan Malaysia 43600 Bangi Selangor Malaysia Marine Ecosystem Research Centre (EKOMAR) Faculty of Science and Technology Universiti Kebangsaan Malaysia 43600 Bangi Selangor Malaysia School of Fisheries andAquaculture Sciences Universiti Malaysia Terengganu 21030 Kuala Terengganu Terengganu Malaysia

Laevistrombus canarium is one of the marine gastropod mollusks that have high commercial value, particularly in the aquaculture sector in Malaysia. This study was conducted to determine the feeding and food items of L. canarium at different ontogenetic stages （juveniles, sub-adults and adults） from Merambong shoals, Malaysia. Field observations on feeding activity were conducted, followed by detailed laboratory analysis on the stomach content. Five-minutes observations on randomly selected individuals were conducted at the field sampling site and their feeding activities were recorded with reference to age stage. Various shell sizes from each ontogenetic stage were randomly collected and quickly anaesthetized with ice and preserved in 10% formalin before being transported to the laboratory for stomach content analyses. Field observations showed that L. canarium mainly grazed on epiphytes occurring on seagrass （46.67%）, followed by sediment surface （40%） and epiphytes occurring on macroalgae （13.33%）. Stomach content analyses showed a significant difference （P〈0.05） in gastro-somatic index （Gasi） between the juveniles （0.39±0.05）, sub-adults （0.68±0.09） and adults （0.70±0.05）（P〈0.05）. Food items found in the conch stomach include diatoms, detritus, foraminifera, seagrass and macroalgae fragments, sand particles and shell fragments. The Index of Relative Importance （%IRI） indicates three main types of food dominated the three ontogenetic stages namely diatoms, sand particles and detritus. However, no significant difference （P〉0.05） was detected between the three main food items （diatoms, sand particles and detritus） among the ontogenetic stages. Therefore, feeding activity revealed the role of the dog conch in the marine food network. While, classification of the types of food consumed by L. canarium through stomach content analysis determines the particular position of the gastropod in the food chain. Further studies are needed to provide a better insight between tr

关键词： Laevistrombus canarium feeding activity gut contents Merambong shoal

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