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作者： sahibzada ahmed noor 北京邮电大学

学位级别：硕士

随着Internet的迅猛发展,因特网已经深入社会和人们的日常生活中。IP协议的出现使得人们可以通过静态方式接入因特网。伴随技术发展,移动IP(MobileIP)越来越受到人们的关注。传统的移动IP只针对单个节点,当前人们正在扩展移动IP从而支...

随着Internet的迅猛发展,因特网已经深入社会和人们的日常生活中。IP协议的出现使得人们可以通过静态方式接入因特网。伴随技术发展,移动IP(MobileIP)越来越受到人们的关注。传统的移动IP只针对单个节点,当前人们正在扩展移动IP从而支持网络移动性(Network Mobility,NEMO)。移动IP对不同的接入技术(WLAN,cellular,broadcast access)提供统一的网络层支持。随着技术进步,节点移动性研究已经向前迈进一大步形成NEMO。所谓NEMO是指一组节点(例如火车、汽车、飞机内部的人员)以子网的方式在移动中接入因特网。NEMO可以保证IP子网在移动的过程中子网内部节点正在进行的会话的连续性。移动的IP子网(mobile network)通过移动路由器(Mobile Router,MR)连接到因特网。这些移动的IP子网可以是由附着在MR上的单个本地节点组成的非嵌套网络,或者是内部嵌套多个IP子网的嵌套网络等。移动网络的不同网络拓扑带来一系列问题,而这些问题在单个节点移动性的研究中并没有出现,这也导致IETF专门成立NEMO工作组。该工作组的主要任务是提出对移动IPV6协议的扩展,从而解决NEMO及其相关问题。实验表明现存的移动IPV6协议无法给移动网络的内部节点转发数据包。本地代理(Home Agent)无法封装要转发给移动网络节点(MNN)的数据包。这是因为从本地代理角度看,HA-MR隧道是节点专用信道而非网络专用信道,因此本地代理只能发现隧道另一端的MR,而无法看到附着在该路由器上的节点。随着个人局域网(PAN)、车域网(CAN)、团体区域网(BAN)的出现以及传统的运输系统需要大量访问因特网,节点移动性协议已经无法满足实际需要,支持NEMO的相关协议呼之欲出。 NEMO基础支持协议(NBS)的提出解决了一组节点作为一个单元的移动接入互联网问题。这个单元称为移动IP子网或移动网络(Mobile Network),一个或多个MR处理来自或到达移动网络的通信。移动网络内部的节点称为移动网络节点(MNN),这些节点包括本地固定节点(LFN’s)、本地移动节点(LMN’s)以及外部的访问移动节点(VMN’s)。这些外部访问移动节点可以是单个移动IPV6节点,也可以是拥有多个MNN的MR。后者称为嵌套移动网络,所谓嵌套网络是指一个移动网络存在于另一个移动网络中。在嵌套移动网络中,被接入的MR称为上行流MR,接入的MR称为下行流MR。嵌套网络中的最顶层MR称为父MR,其下的所有MR称为子MR。不包含任何子网络的移动网络的嵌套等级为1,因此嵌套等级2表明一个小的移动网络嵌套在一个大的移动网络的内部。每个MR都有唯一的IP地址进行标示,称为本地地址,其在家乡链路上都有一个本地代理或称家乡代理(Home Agent,HA)。HA负责MR发送的数据在家乡网络的传递,它存储对应的MR的本地地址。当MR访问外部网络时,外部网络向MR提供一个转发地址(CoA),MR将转发地址与本地地址绑定,这种绑定称为绑定更新(BU)。MR将绑定更新发送给HA,HA将绑定更新的内容存储在绑定缓存中。接着HA向MR发送绑定确认,当成功完成该绑定过程后,MR与对应的HA之间的MR-HA隧道建立完成。此后所有发往移动网络的数据包首先由HA截取,通过添加标有转发地址的外部IP头进行封装,接着通过HA-MR隧道到达当前MR的转发地址。与进入移动网络的数据包相似,所有从移动网络的数据包同样需要经过MR添加IP头进行封装,然后通过HA-MR“双向隧道”传输。根据NEMO基础支持协议,所有在MR和对应节点(CN)之间通信的数据包都需要经过“双向隧道”传输。然而当MR和CN距离很近,却远离HA时,这可能导致长的路由以及大的包传输时延,影响服务质量。此外,长的路由路径将给路由网络增添额外的负载,从而增大链路中断的概率。每当数据包经由“双向隧道”时需要添加额外的IPV6路由头,这增大数据包的尺寸进而降低整体的带宽利用率,而且如果包尺寸超过链路的最大传输单元限制,需要拆分数据包从而增大包时延。此外,节点的封装处理同样也增大包的传输时延。根据NEMO基础支持协议,所有发自移动网络的流量都需要经由家乡链路到达目的地,这可能导致拥塞(瓶颈效应)。一旦家乡链路出现故障将导致所有进出移动网络的通信中断。由于担心流氓用户可能通过“双向隧道”向家乡网络发动攻击,安全策略阻止MR传输访问移动网络向家乡网络发送的流量。在嵌套网络中,如果两个移动通信节点需要通信,则所有的数据包都需要通过所有的上行流MR和对应的HA,这既增大包头同时也导致大的包传输时延。换一种情形,如果某个HA嵌套在某个移动网络中,则死循坏发生。MR无法找到其对应的HA进而无法建立“

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A Study of Three Different Obturating Techniques for Apical Microleakage in Human Teeth

A Study of Three Different Obturating Techniques for Apical ...

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作者： sahibzada MOHAMMAD noor 中南大学

学位级别：硕士

目的:利用葡萄糖定量法检测根管微渗漏的模型,评价侧向加压充填技术、垂直加压充填技术及固核载体充填技术对根管微渗漏的影响。方法:选取71颗直根管上前牙,根管预备后随机分为七组,A组(14颗)用热牙胶垂直加压加AH Plus充填,B组(8颗)仅... 详细信息

目的:利用葡萄糖定量法检测根管微渗漏的模型,评价侧向加压充填技术、垂直加压充填技术及固核载体充填技术对根管微渗漏的影响。方法:选取71颗直根管上前牙,根管预备后随机分为七组,A组(14颗)用热牙胶垂直加压加AH Plus充填,B组(8颗)仅用热牙胶垂直加压充填,C组(13颗)用侧方加压加AH Plus充填,D组(8颗)仅用侧方加压充填技术,E组(11颗)用Thermafil加AH Plus充填,F组(7颗)仅用Thermafil充填,G组(10颗)为阴性对照组,用粘蜡充填根管,牙根外表面及根尖孔处涂二层指甲油。于第7、14、21、28天用葡萄糖氧化酶法检测从冠方向根方漏出的葡萄糖量。结果:采用重复测量方差分析,发现第7、14、21、28天A、C组及C、E组微渗漏值有显著性差异(P＜0.001),但A、E组无显著性差异(P＞0.05)。各时间点C、D组比较有显著性差异(P＜0.001),但A、B组与E、F组比较无显著性差异(P＞0.05)。第7、14天及第21、28天各组内比较无显著性差异(P＞0.05),但各组第14天与第21天比有显著性差异(P＜0.05)。结论:侧方加压充填技术封闭根管的能力优于垂直加压充填技术及固核载体充填技术,而后两种充填技术封闭根管的能力相当。

关键词：侧向加压充填技术垂直加压充填技术 Thermafil充填技术 AH Plus根管封闭剂根管微渗漏根管充填

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Deep Learning Framework for Precipitation Prediction Using Cloud Images

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Computers, Materials & Continua 2022年第8期72卷 4201-4213页

作者： Mirza Adnan Baig Ghulam Ali Mallah noor ahmed Shaikh Shah Abdul Latif University Khairpur77150Pakistan

Precipitation prediction(PP)have become one of the significant research areas of deep learning(DL)and machine vision(MV)techniques are frequently used to predict the weather variables(WV).Since the climate change has left significant impact upon weather variables(WV)and continuously changes are observed in temperature,humidity,cloud patterns and other *** cloud images contain sufficient information to predict the precipitation pattern but due to changes in climate,the complex cloud patterns and rapid shape changing behavior of clouds are difficult to consider for rainfall *** of rainfall would provide more meticulous assistance to the farmers to know about the weather conditions and to care their cash *** research proposes a framework to classify the dark cloud patterns(DCP)for prediction of *** framework consists upon three steps to classify the cloud images,first step tackles noise reduction operations,feature selection and preparation of *** step construct the decision model by using convolutional neural network(CNN)and third step presents the performance visualization by using confusion matrix,precision,recall and accuracy *** research contributes(1)real-world clouds datasets(2)method to prepare datasets(3)highest classification accuracy to predict estimated as 96.90%.

关键词： Machine vision SIFT features dark cloud patterns precipitation agriculture

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Competitive role of nitrogen functionalities of N doped GO and sensitizing effect of Bi_(2)O_(3)QDs on TiO_(2)for water remediation

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Journal of Environmental Sciences 2021年第10期33卷 107-119页

作者： Saima noor Shamaila Sajjad Sajjad ahmed Khan Leghari Cristina Flox Saeed Ahmad International Islamic University Islamabad 44000Pakistan Department of Chemistry and Materials Science Aalto UniversityEspoo 16100Fl-00076Finland Pakistan Institute of Engineering and Applied Sciences Islamabad 44000Pakistan Department of Applied Physics Aalto UniversityEspoo 15100Fl-00076Finland

The promising solar irradiated photocatalyst by pairing of bismuth oxide quantum dots(BQDs)doped TiO_(2)with nitrogen doped graphene oxide(NGO)nanocomposite(NGO/BQDs-TiO_(2))was *** was used for degradation of organic pollutants like 2,4-dichlorophenol(2,4-DCP)and stable dyes,*** B and Congo Red.X-ray diffraction(XRD)profile of NGO showed reduction in oxygenic functional groups and restoring of graphitic crystal *** characteristic diffraction peaks of TiO_(2)and its composites showed crystalline anatase TiO_(2).Morphological images represent spherical shaped TiO_(2)evenly covered with BQDs spread on NGO *** surface linkages of NO-O-Ti,C-O-Ti,Bi-O-Ti and vibrational modes are observed by Fourier transform infrared spectroscopy(FTIR)and Raman *** and NGO modified TiO_(2)results into red shifting in visible region as studied in diffused reflectance spectroscopy(DRS).NGO and BQDs in TiO_(2)are linked with defect centers which reduced the recombination of free charge carriers by quenching of photoluminescence(PL)intensities.X-ray photoelectron spectroscopy(XPS)shows that no peak related to C-O in NGO/BQDs-TiO_(2)is *** indicated that doping of nitrogen into GO has reduced some oxygen functional *** functionalities in NGO and photosensitizing effect of BQDs in ternary composite have improved photocatalytic activity against organic *** byproducts during photo degradation process of 2,4-DCP were studied through high performance liquid chromatography(HPLC).Study of radical scavengers indicated that O_(2)^(·-) has significant role for degradation of 2,*** investigations propose that fabricated nanohybrid architecture has potential for degradation of environmental pollutions.

关键词： Bi_(2)O_(3)quantum dots Nitrogen doped graphene oxide Nitrogen defects TiO_(2) 2,4-Dichlorophenol Water treatment

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Energy-Efficient Scheduling for a Cognitive IoT-Based Early Warning System

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Computers, Materials & Continua 2022年第6期71卷 5061-5082页

作者： Saeed ahmed noor Gul Jahangir Khan Junsu Kim Su Min Kim Department of Electronics Engineering Korea Polytechnic UniversitySiheung15073Korea Mirpur University of Science and Technology Mirpur10250Pakistan Department of Electronics University of PeshawarPeshawar25120Pakistan Sarhad University of Science and Information Technology Peshawar25000Pakistan

Flash floods are deemed the most fatal and disastrous natural hazards globally due to their prompt onset that requires a short prime time for emergency *** Internet of things(CIoT)technologies including inherent characteristics of cognitive radio(CR)are potential candidates to develop a monitoring and early warning system(MEWS)that helps in efficiently utilizing the short response time to save lives during flash ***,most CIoT devices are battery-limited and thus,it reduces the lifetime of the *** tackle these problems,we propose a CIoTbased MEWS to slash the fatalities of flash *** extend the lifetime of the MEWS by conserving the limited battery energy of CIoT sensors,we formulate a resource assignment problem for maximizing energy *** solve the problem,at first,we devise a polynomial-time heuristic energyefficient scheduler(EES-1).However,its performance can be unsatisfactory since it requires an exhaustive search to find local optimum values without consideration of the overall network energy *** enhance the energy efficiency of the proposed EES-1 scheme,we additionally formulate an optimization problem based on a maximum weight matching bipartite ***,we additionally propose a Hungarian algorithm-based energy-efficient scheduler(EES-2),solvable in polynomial *** simulation results show that the proposed EES-2 scheme achieves considerably high energy efficiency in the CIoT-based MEWS,leading to the extended lifetime of the MEWS without loss of throughput performance.

关键词： Flash floods internet of things cognitive radio early warning system network lifetime energy efficiency

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Characteristics and advantages of adeno-associated virus vector-mediated gene therapy for neurodegenerative diseases

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Neural Regeneration Research 2019年第6期14卷 931-938页

作者： Yuan Qu Yi Liu ahmed Fayyaz noor Johnathan Tran Rui Li Department of Hand Surgery the Second Hospital of Jilin University Department of Orthopedics Qilu Hospital of Shandong University Department of Chemistry University of Massachusetts Lowell Department of Premedical and Health Studies Massachusetts College of Pharmacy and Health Sciences

Common neurodegenerative diseases of the central nervous system are characterized by progressive damage to the function of neurons, even leading to the permanent loss of function. Gene therapy via gene replacement or gene correction provides the potential for transformative therapies to delay or possibly stop further progression of the neurodegenerative disease in affected patients. Adeno-associated virus has been the vector of choice in recent clinical trials of therapies for neurodegenerative diseases due to its safety and efficiency in mediating gene transfer to the central nervous system. This review aims to discuss and summarize the progress and clinical applications of adeno-associated virus in neurodegenerative disease in central nervous system. Results from some clinical trials and successful cases of central neurodegenerative diseases deserve further study and exploration.

关键词： nerve regeneration central nervous system gene therapy neurodegenerative disease viral vector adeno-associated virus Alzheimer’s disease Parkinson’s disease Huntington’s disease amyotrophic lateral sclerosis spinal muscular atrophy neural regeneration

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Optimal Cooperative Spectrum Sensing Based on Butterfly Optimization Algorithm

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Computers, Materials & Continua 2022年第4期71卷 369-387页

作者： noor Gul Saeed ahmed Atif Elahi Su Min Kim Junsu Kim Department of Electronics Engineering Korea Polytechnic University15073Gyeonggi-doKorea Department of Electronics University of Peshawar25120Pakistan Department of Electrical Engineering Mirpur University of Science of TechnologyAJ&K10250Pakistan Department of Electrical Engineering International Islamic UniversityIslamabad 44000Pakistan

Since the introduction of the Internet of Things(IoT),several researchers have been exploring its productivity to utilize and organize the spectrum *** radio(CR)technology is characterized as the best aspirant for wireless communications to augment IoT *** the CR networks,secondary users(SUs)opportunistically get access to the primary users(PUs)spectrum through spectrum *** multipath issues in the wireless channel can fluster the sensing ability of the individual ***,several cooperative SUs are engaged in cooperative spectrum sensing(CSS)to ensure reliable sensing *** CSS,security is still a major concern for the researchers to safeguard the fusion center(FC)against abnormal sensing reports initiated by the malicious users(MUs).In this paper,butterfly optimization algorithm(BOA)-based soft decision method is proposed to find an optimized weighting coefficient vector correlated to the SUs sensing *** coefficient vector is utilized in the soft decision rule at the FC before making any global *** effectiveness of the proposed scheme is compared for a variety of parameters with existing schemes through simulation *** results confirmed the supremacy of the proposed BOA scheme in both the normal SUs’environment and when lower and higher SNRs information is carried by the different categories of MUs.

关键词： Internet of Things cognitive radio network butterfly optimization algorithm particle swarm optimization malicious users genetic algorithm

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Reconfigurable Sensing Time in Cooperative Cognitive Network Using Machine Learning

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Computers, Materials & Continua 2023年第3期74卷 5209-5227页

作者： noor Gul Saeed ahmed Su Min Kim Muhammad Sajjad Khan Junsu Kim Department of Electronics Engineering Korea Polytechnic UniversityGyeonggi-do15073Korea Department of Electronics University of PeshawarPeshawar25120Pakistan Deparment of Electrical Engineering Mirpur University of Science of TechnologyAJ&KMirpur10250Pakistan Department of Electrical Engineering International Islamic UniversityIslamabad44000Pakistan

A cognitive radio network(CRN)intelligently utilizes the available spectral resources by sensing and learning from the radio environment to maximize spectrum *** CRNs,the secondary users(SUs)opportunistically access the primary users(PUs)***,unambiguous detection of the PU channel occupancy is the most critical aspect of the operations of *** spectrum sensing(CSS)is rated as the best choice for making reliable sensing *** paper employs machinelearning tools to sense the PU channels reliably in *** sensing parameters are reconfigured to maximize the spectrum utilization while reducing sensing error and cost with improved channel *** fine-k-nearest neighbor algorithm(FKNN),employed in this paper,estimates the number of samples based on the nature of the channel under-specific detection and false alarm probability *** simulation results reveal that the sensing cost is suppressed by reducing the sensing time and exploiting the traditional fusion rules,validating the effectiveness of the proposed ***,the global decision made at the fusion center(FC)based on the modified sensing samples,results low energy consumption,higher throughput,and improved detection with low error probabilities.

关键词： Energy detection machine learning k-nearest-neighbor decision tree linear regression throughput energy consumption

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Reservoir characteristics of Datta Formation (Early Jurassic), Marwat-Khisor Ranges, sub-Himalayas, Pakistan

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Petroleum Science 2023年第4期20卷 2026-2044页

作者： Muhammad Tariq Muhammad Kashif noor ahmed Zaheen Ullah Jose Nicanor Mendez Muhammad Armaghan Faisal Miraj Department of Earth Sciences University of SargodhaSargodha40100Pakistan Department of Geosciences University of BaltistanSkarduPakistan School of Geosciences China University of PetroleumQingdao266580China Institute of Geology University of the PunjabLahorePakistan

The present work has been accomplished to carry out a detailed study of the characteristics of the Early Jurassic Datta Formation of Trans-Indus Ranges, Pakistan. The discovery of Saib well-1 (Gas and condensate discovery from Jurassic limestone) in the study basin takes an active interest in carrying out extensive exploration activities in the same basin. Jurassic rocks especially Datta Sandstone and Samana Suk Limestone are acting as good reservoirs. The study unit consists of variegated sandstone interbedded with siltstone, carbonaceous clay, and shale and coal stringer. For the current work, two stratigraphic sections (Pezu and Abbo Wanda) have been measured. To examine its sedimentology, depositional environment, diagenetic settings, and reservoir characteristics, a detailed study was conducted and various laboratory techniques have been utilized. About 95 rock samples from the bottom to the top of both sections were collected, and 50 rock samples have been selected for thin section analysis and were examined under a polarizing microscope to show their mineralogical composition, diagenesis, and their reservoir characteristics. XRD (X-ray diffraction), Cathodoluminescence (CL), SEM (Scanning electron microscope) with EDS (Energy-dispersive spectroscope), and Core plug porosity and permeability analysis have been used to interpret its chemical and mineralogical composition and its reservoir characteristics, respectively. Based on field observations and thin section analysis, four depositional facies and six lithofacies have been established. The sedimentary structures, depositional facies, and lithofacies indicate that Datta Formation was deposited in a deltaic environment. Compactions, cementation, fracturing and dissolution can greatly affect the quality of reservoir rock. Based on thin section and SEM analysis, large numbers of primary pores, fracture and secondary pores were observed and connectivity between the pores is good, and at some places, these pores

关键词： Reservoir characteristics Jurassic Datta Formation Porosity.permeability Sandstone

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Machine Learning-based Stable P2P IPTV Overlay

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Computers, Materials & Continua 2022年第6期71卷 5381-5397页

作者： Muhammad Javid Iqbal Ihsan Ullah Muhammad Ali Atiq ahmed Waheed noor Abdul Basit Directorate of Information Technology Sardar Bahadur Khan Women’s UniversityQuettaPakistan Department of Computer Science and Information Technology University of BalochistanQuettaPakistan

Live video streaming is one of the newly emerged services over the Internet that has attracted immense interest of the service *** Internet was not designed for such services during its inception,such a service poses some serious challenges including cost and ***-to-Peer(P2P)Internet Protocol Television(IPTV)is an application-level distributed paradigm to offer live video *** terms of ease of deployment,it has emerged as a serious alternative to client server,Content Delivery Network(CDN)and IP multicast ***,P2P approach has struggled to provide the desired streaming quality due to a number of *** of peers in a network is one of themajor issues among *** of the existing approaches address this issue through older-stable *** paper first extensively investigates the older-stable principle to observe its validity in different *** is observed that the older-stable principle does not hold in several of ***,it utilizes machine learning approach to predict the stability of *** work evaluates the accuracy of severalmachine learning algorithms over the prediction of stability,where the Gradient Boosting Regressor(GBR)out-performs other ***,this work presents a proof-of-concept simulation to compare the effectiveness of older-stable rule and machine learning-based predictions for the stabilization of the *** results indicate that machine learning-based stability estimation significantly improves the system.

关键词： P2P IPTV live video streaming user behavior overlay networks stable peers machine learning

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