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作者： ahsan jamal akbar 上海交通大学

学位级别：硕士

随着室内环境中无线系统的惊人发展和无线技术的广泛部署,许多基于位置的室内服务(LBS)已经渗透到当代生活的方方面面。在室内环境中,使用无线设备定位目标是最重要的功能之一。在各种室内定位应用中,室内定位技术主要分为两大类:基于... 详细信息

随着室内环境中无线系统的惊人发展和无线技术的广泛部署,许多基于位置的室内服务(LBS)已经渗透到当代生活的方方面面。在室内环境中,使用无线设备定位目标是最重要的功能之一。在各种室内定位应用中,室内定位技术主要分为两大类:基于设备的定位服务(Device Based,DB)和无设备的定位服务(Device Free,DF)。基于设备的定位应用需要待定位对象携带特定的硬件设备,进而完成定位。,无设备的定位应用则不需要待定位对象携带任何额外的设备。由于Wi-Fi在无线网络基础设施中占据主导地位,基于Wi-Fi的室内定位应用已经成为一种广泛应用的室内定位技术。大多数基于Wi-Fi的室内定位系统利用接收信号强度(Received Signal Strength Indicator,RSSI)实现室内定位。但是,RSSI只是一种粒度较粗的测量值,而且RSSI会随着时间变化,具有一定的时间波动性。不同于RSSI,物理层的功率特性和信道响应可以区分无线信号多径分量的特性,因此利用物理层信息更可能实现精度高和稳定性好的定位系统。因此,很多室内定位的研究将研究重点转向了信道状态信息(Channel State Information,CSI),并且一些基于CSI的开创性的工作已经取得了亚米级别甚至分米级别的定位精度。本文利用CSI在复杂的室内环境下实现高精度的室内定位,通过校准物理层的CSI信息来消除由信道或者硬件的信号衰减引起的信号误差,然后提出了一种独特的MUSIC算法用来估计到达角(Angle Of Arrival,AOA)和信号传输时间(Signal Time Of Flight,STOF)。室内环境复杂多变,无线信号在室内环境下会产生多径效应,使用多重信号分类(Multiple Signal Classification,MUSIC)算法可以估算得到多个不同传播路径的到达角和信号传输时间。本文结合k均值聚类算法从信号的多径分量中识别直接路径,首先将估算得到的AOA和STOF作为二维坐标,然后对坐标点进行聚类,聚类完成之后,通过分析衡量直接路径的多个因素,定义了一个可以衡量直接路径可能性的函数,将可能性最大的聚类当作直接路径。本文提出了基于MUSIC算法和优化到达角的室内定位系统(Target Discovery Using MUSIC,TDUM),该系统使用商用Wi-Fi接入点实现了分米级别的室内定位。在典型的室内环境下使用商用的无线网卡进行了大量实验,实验结果还表明本文提出的算法在估算AOA和识别直接路径方面具有较好的性能,另外本文提出的室内定位系统在稳定性和定位精度上可与现有的高精度定位系统相媲。

关键词：目标定位接收信号强度信道状态信息接入点到达角信号传输时间

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Metal-Doped Brushite Cement for Bone Regeneration

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Journal of Bionic Engineering 2023年第6期20卷 2716-2731页

作者： Muhammad Aqib Aneela Anwar Humayun Ajaz Samina akbar ahsan Manzoor Maham Abid Zohaib Waheed Qudsia Kanwal Department of Chemistry University of Engineering and TechnologyGT RoadLahore54890Pakistan Department of Chemistry University of LahoreLahore5400Pakistan

For the past several years,calcium phosphate cement was used in the biomedical *** biocompatibility,good bioactivity,self-setting qualities,minimum setting degree,appropriate toughness,and simple shape to accommodate any difficult geometry are among their most notable *** phosphate has some types and brushite is one of the most attractive mineral for bone repair *** is extensively employed in filling fractures and trauma treatments as a bone substituted *** kind of material can potentially be used as a medicine delivery *** replacement of metal,such as magnesium,zinc,and strontium ions,into the calcium phosphate structure is a major research topic these *** cement has low mechanical strength and quick setting *** is possible to produce biomaterials with higher mechanical *** adding metal that are great potential in controlling cellular density when included into *** a result,it is a successful method to develop quite well regenerative *** paper provides a detailed summary of the present achievements of metal-doped brushite cement for bone repair and healing *** major purpose of this work is to give a simple but thorough analysis of current successes in brushite cement doped with Zn,Mg,Sr,and other ions as well as to highlight new advancements and *** impact of metal replacement on cement physical and chemical properties,including microstructure,setting time,injectability,mechanical property,and ion release,is *** metal-doped cement has osteogenesis,angiogenesis,and antibacterial properties,as well as their prospective utility as drug carriers,also considered.

关键词： Calcium phosphate Brushite Bone cement Metal dopants Bone regeneration

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Variable range hopping transport and dielectric relaxation mechanism in GdCrO_(3) rare-earth orthochromite perovskite

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Journal of Rare Earths 2024年第7期42卷 1304-1316,I0004页

作者： Muhammad Javed Ayaz Arif Khan jamal Kazmi Naeem akbar Said Nasir Khisro Amanullah Dar Aleem Dad Khan Tareen Mohd Ambri Mohamed Department of Physics The University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Physics University of Kotli Azad Jammu and KashmirKotli11100Pakistan Institute of Microengineering and Nanoelectronics Universiti Kebangsaan Malaysia43600BangiSelangorMalaysia Department of Mathematics University of Kotli Azad Jammu and KashmirKotli11100Pakistan

The polycrystalline GdCrO_(3)(GCO)perovskite orthochromite was synthesized by the sol-gel auto-combustion *** Rietveld refined X-ray diffraction(XRD)profile of GCO confirms that the orthorhombic phase crystallizes in perovskite crystal structure with space group *** transmission electron microscopy and selected area electron diffraction divulge the polycrystalline nature of the perovskite *** field emission scanning electron microscopy(FESEM)images reveal the microstructural polyhedral growth of grains separated by sharp grain *** chemical states of the ions present in the compound were investigated by X-ray photoelectron spectroscopy(XPS)studies,and the electrical pathways were *** impedance studies were carried out in the experimental frequency and temperature ranges of 40 Hz-4 MHz and 178-408 K,*** equivalent circuit model(RGQG)(RGBQGB)resolves the impedance response into two contributions originating from the intra-grain and inter-granular micro-constituents of the *** electrical conduction mechanism is based on the Mott variable range hopping *** complex electric modulus studies demonstrate the short-and long-range mobility of the charge carriers and rule out the presence of electrode effects on the dielectric relaxation mechanism of the *** decreasing pattern of dielectric permittivity with frequency is explained by the Maxwell-Wagner type of *** frequency dependence of the loss factor exhibits the presence of thermally activated relaxation time distribution in the material.

关键词： Auto-combustion Perovskite Electro-ceramic Dielectric Electrical transport Impedance

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In vitro scolicidal effect of Satureja khuzistanica(Jamzad)essential oil

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Asian Pacific Journal of Tropical Biomedicine 2012年第8期2卷 616-620页

作者： Mohammad Moazeni Mohammad jamal Saharkhiz Ali akbar Hoseini Amir Mootabi Alavi Department of Pathobiology School of Veterinary MedicineShiraz University Department of Horticultural Science Collage of AgricultureShiraz University Graduate Student of Veterinary Medicine School of Veterinary MedicineShiraz University

Objective:To investigate the scolicidal effect of the Satureja khuzistanica(***) essential oil from aerial parts of this herbal ***:The essential oil was obtained by hydrodistillation *** chromatography(GC) and gas chromatography mass spectrometry(GC-MS) were employed to determine the chemical composition of the essential *** were collected aseptically from sheep livers containing hydatid *** were exposed to various concentrations of the oil(3,5 and 10 mg/mL) for 10,20,30,and 60 *** of protoscolices was confirmed by 0.1%eosin ***:A total of 19 compounds representing 97.6%of the total oil,were ***(94.9%) was found to be the major essential oil *** activity of *** essential oil at concentration of 3 mg/mL was 28.58,32.71,37.20 and 42.02%,*** essential oil at concentration of 5 mg/ mL killed 51.33,66.68,81.12,and 100%.of protoscolices after 10,20,30 and 60 min,respectively. One hundred scolicidal effect was observed with *** essenlial oil at the concentration of 10 mg/mL after 10 min(comparing with 7.19%for control group).Conclusions:The essenlial oil of *** is rich in carvacrol and may be used as a natural scolicidal agent.

关键词： Hydatid cyst Scolicidal Essential oil Carvacrol Satureja khuzistanica

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An Investigation of Radiation Protection Status in Radiology Centers of Kurdistan in 2014-2015

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Health 2017年第5期9卷 849-856页

作者： Leila Ebrahimzadeh akbar Eslami Farzam Bidarpoor Seyyed jamal Aldin Ebrahimi Department of Environmental Health Engineering Kurdistan University of Medical Sciences Sanandaj Iran Department of Environmental Health Engineering Shahid Beheshti University of Medical Sciences Tehran Iran Deputy of Health Kurdistan University of Medical Sciences Sanandaj Iran

Using personal protective equipment (PPE) properly and following available rules and regulations in the field of ionizing radiation protection can significantly decrease these harms. If these equipment and facilities are not available in diagnostic radiation centers or are not used properly, radiographers’ and people’s health will be jeopardized. To date, no study has examined the protective condition against radiation in diagnostic radiation centers of Kurdistan province. The present study, therefore, was an attempt to address this gap. This cross-sectional study was conducted in 2014-2015 among 35 diagnostic radiation centers of Kurdistan. Data were collected through a checklist (which was developed based on the available radiation protection laws), a survey for patients and their caregivers, and insite observation and dosimetry. The radiation health expert of the province proceeded to each of the radiology centers personally. Upon arrival to each center, he informed health physics officials of the centers about the study and collected data through observation, interview, and the checklist. On the other hand, in order to examine radiation leakage in different modes of imaging session, dosimetry was conducted by the use of an environmental dosimeter (Fluke 451 manufactured in the United States). The collected data were analyzed through Excel. It was found that in 67.3% of the cases, there was personal protective equipment for patients and their caregivers (robes, thyroid strap, gonadal shield, glasses, and lead gloves). Furthermore, this equipment and other physical holders were used for patients and their caregivers in 75.7% of the cases. This rate was 87.6% for pregnant women. In addition, we found that around 94% of the personnel went through medical examinations every six or twelve months, a rate that was much higher than that found in Nohi’s study. When it comes to improving the indices of protection against radiation in radiation centers, it seems that adding

关键词： Radiation Protection Diagnostic Radiology Centers Kurdistan

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Reprogramming Mycobacterium tuberculosis CRISPR System for Gene Editing and Genomewide RNA Interference Screening

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Genomics, Proteomics & Bioinformatics 2022年第6期20卷 1180-1196页

作者： Khaista Rahman Muhammad jamal Xi Chen Wei Zhou Bin Yang Yanyan Zou Weize Xu Yingying Lei Chengchao Wu Xiaojian Cao Rohit Tyagi Muhammad ahsan Naeem Da Lin Zeshan Habib Nan Peng Zhen F.Fu Gang Cao State Key Laboratory of Agricultural Microbiology Huazhong Agricultural UniversityWuhan 430070China College of Veterinary Medicine Huazhong Agricultural UniversityWuhan 430070China Bio-Medical Center Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Preventive Veterinary Medicine in Hubei Province the Cooperative Innovation Center for Sustainable Pig ProductionWuhan 430070China

Mycobacterium tuberculosis is the causative agent of tuberculosis(TB), which is still the leading cause of mortality from a single infectious disease worldwide. The development of novel anti-TB drugs and vaccines is severely hampered by the complicated and time-consuming genetic manipulation techniques for M. tuberculosis. Here, we harnessed an endogenous type Ⅲ-A CRISPR/Cas10 system of M. tuberculosis for efficient gene editing and RNA interference(RNAi).This simple and easy method only needs to transform a single mini-CRISPR array plasmid, thus avoiding the introduction of exogenous protein and minimizing proteotoxicity. We demonstrated that M. tuberculosis genes can be efficiently and specifically knocked in/out by this system as confirmed by DNA high-throughput sequencing. This system was further applied to single-and multiple-gene RNAi. Moreover, we successfully performed genome-wide RNAi screening to identify M. tuberculosis genes regulating in vitro and intracellular growth. This system can be extensively used for exploring the functional genomics of M. tuberculosis and facilitate the development of novel anti-TB drugs and vaccines.

关键词： Mycobacterium tuberculosis Type III-A CRISPR system Gene editing Gene interference Genome-wide RNAi screening

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