检索结果-南通市图书馆

A Novel Genetic Algorithm for Stable Multicast Routing in Mobile Ad Hoc Networks

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Communications 2019年第8期16卷 24-37页

作者： Qiongbing Zhang lixin ding Zhuhua Liao School of Computer Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Computer Wuhan UniversityWuhan 430072China

Data transmission among multicast trees is an efficient routing method in mobile ad hoc networks(MANETs). Genetic algorithms(GAs) have found widespread applications in designing multicast trees. This paper proposes a stable quality-of-service(QoS) multicast model for MANETs. The new model ensures the duration time of a link in a multicast tree is always longer than the delay time from the source node. A novel GA is designed to solve our QoS multicast model by introducing a new crossover mechanism called leaf crossover(LC), which outperforms the existing crossover mechanisms in requiring neither global network link information, additional encoding/decoding nor repair procedures. Experimental results confirm the effectiveness of the proposed model and the efficiency of the involved GA. Specifically, the simulation study indicates that our algorithm can obtain a better QoS route with a considerable reduction of execution time as compared with existing GAs.

关键词： Quality-of-Service(QoS) multicast genetic algorithm leaf crossover

Evolution and significance of the psychosomatic model in gastroenterology

在线全文

学校读者我要写书评

暂无评论

General Psychiatry 2022年第5期35卷 297-302页

作者： Qiaoli Zhang lixin ding Jianxin Cao Institute of Psychosomatic Gastroenterology Soochow UniversityChangzhouChina Department of Gastroenterology The Third Affiliated HospitalSoochow UniversityChangzhouChina

The biomedical model,which limits itself to finding the attributions of organic disease,is challenged by gastrointestinal(GI)***,physicians'attribution of GI symptoms to underlying psychological issues is not readily accepted by patients and can negatively affect the clinical rapport between doctor and *** reality,psychosocial aspects are involved in many functional disorders and organic diseases,not just in mental *** is overdue for gastroenterologists to recognise the inadequacy and limitations of conventional gastroenterology and consider the role of psychological,social and biological variables throughout the entire clinical course of the illness,as is shown in George Engel’s *** review discusses the following:(1)the current challenges of using the conventional clinical model for both functional and organic GI illness,(2)the inadequacy and limitations of explaining GI symptoms simply as psychological disorders,(3)the exploration of the symptom-centred,stepped reattribution clinical model,(4)the clarification of psychosomatic medical concepts for use in gastroenterology,and(5)the significance of a systematic and interdisciplinary framework for a comprehensive psychosomatic model in gastroenterology.

关键词： gastro psychological readily

A Cost-Effective Cloud Leasing Policy for Live Streaming Applications

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2017年第6期22卷 477-481页

作者： ZHANG Qiongbing ding lixin YANG Li School of Computer Wuhan University College of Computer Hubei University of Education

The dynamics of the globalized multimedia sources and request demands, which requires high computations and bandwidths, makes the IT infrastructure a challenge for live streaming applications. Migrating the system to a geo-distributed cloud and leasing servers is an ideal alternative for supporting large-scale live streaming applications with dynamic contents and demands. The new challenge of multimedia live streaming applications in a geo-distributed cloud is how to efficiently arrange and migrate services among different cloud sites to guarantee the distribute users’ experience at modest costs. This paper first investigates cloud leasing policies for live streaming applications and finds that there is no detailed algorithm to help live streaming applications arrange and migrate services among different cloud sites. Then, we present a quality of service（Qo S） guarantee cost-effective cloud leasing policy for live streaming applications. Meanwhile, we design a genetic algorithm（GA） to deal with the leasing policy among cloud sites of diverse lease prices. Experimental results confirm the effectiveness of the proposed model and the efficiency of the involved GA.

关键词： live streaming applications cloud leasing policy genetic algorithm

Using Evolutionary Computation to Solve Problems in Nonparametric Regression

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 1998年第1期3卷 27-31页

作者： ding lixin Kang Lishan Chen Yuping Pan Zhengjun Wuhan University State Key Lab of Software Engineering Wuhan China (GRID:grid.49470.3e) (ISNI:***)

This paper studies evolutionary mechanism of parameter selection in the construction of weight function for Nearest Neighbour Estimate in nonparametric regression. Construct an algorithm which adaptively evolves fine weight and makes good prediction about unknown points. The numerical experiments indicate that this method is effective. It is a meaningful discussion about practicability of nonparametric regression and methodology of adaptive model-building.

关键词： nonparametric regression Nearest Neighbour Estimate evolutionary computation nonhomogeneous selection adaptive model-building

A Robust Face Recognition Method Using Multiple Features Fusion and Linear Regression

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2014年第4期19卷 323-327页

作者： GAO Zhirong ding lixin XIONG Chengyi HUANG Bo School of Computer Wuhan University College of Computer Science South-Central University for Nationalities College of Electronics and Information South-Central University for Nationalities Shenzhen Institute of Wuhan University

This paper presents a robust face recognition algorithm by using transform domain-based multiple feature fusion and lin- ear regression. Transform domain-based feature fusion can provide comprehensive face information for recognition, and decrease the effect of variations in illumination and pose. The holistic feature and local feature are extracted by discrete cosine transform and Gabor wavelet transform, respectively. Then the extracted holistic features and the local features are fused by weighted sum. The fused feature values are finally sent to linear regression classifier for recognition. The algorithm is evaluated on AR, ORL and Yale B face databases. Experiment results show that our proposed algo- rithm could be more robust than those single feature-based algo- rithms under pose and expression variations.

关键词： holistic feature local feature weighted fusion

Establishment and Application of a Radiation Dose Rate Model for Nuclear Medicine Examinees

在线全文

学校读者我要写书评

暂无评论

China CDC weekly 2024年第23期6卷 553-557,I0019-I0025页

作者： Yuehua Hu Xinyu He Wenjia Zhao lixin ding Meiying You Zihan Li Xinyu Liu Miaomiao Wang Siyi Chen Ziwei Lu Lei Qu Kuke ding Li Zhang Qiuxian Fu Office of Epidemiology Chinese Center for Disease Control and PreventionBeijingChina Department of Oncology Central Hospital Affiliated to Shandong First Medical UniversityJinan CityShandong ProvinceChina National Institute for Radiological Protection Chinese Center for Disease Control and PreventionBeijingChina National Center for Chronic and Noncommunicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Laboratory Animal Center Chinese Center for Disease Control and PreventionBeijingChina National Institute of Parasitic Diseases Chinese Center for Disease Control and PreventionShanghaiChina Office of Public Health Management Chinese Center for Disease Control and PreventionBeijingChina Hainan Medical University Haikou CityHainan ProvinceChina

Introduction:Traditional methods for determining radiation dose in nuclear medicine include the Monte Carlo method,the discrete ordinate method,and the point kernel integration *** study presents a new mathematical model for predicting the radiation dose rate in the vicinity of nuclear medicine ***:A new algorithm was created by combining the physical model of“cylinder superposition”of the human body with integral analysis to assess the radiation dose rate in the vicinity of nuclear medicine ***:The model accurately predicted radiation dose rates within distances of 0.1–3.0 m,with a deviation of less than 11%compared to observed *** model demonstrated greater accuracy at shorter distances from the radiation source,with a deviation of only 1.55%from observed values at 0.1 ***:The model proposed in this study effectively represents the spatial and temporal distribution of the radiation field around nuclear medicine patients and demonstrates good agreement with actual *** model has the potential to serve as a radiation dose rate alert system in hospital environments.

关键词： method. deviation cylinder

胰升糖素样肽1与胰升糖素样肽1受体激动剂的血压效应及作用机制的研究进展

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中华内分泌代谢杂志 2020年第9期36卷 811-816页

作者：丁立新高新人民医院内分泌科宝鸡721000

作为一类新型降糖药,胰升糖素样肽1受体激动剂的血压效应日益受到重视。在动物研究中,急、慢性用药却表现出不同的血压效应;临床系列研究已肯定这类药物慢性用药的降压作用,不同药物降压效果无明显差异。脑干神经核团、心脏、肾脏、血... 详细信息

作为一类新型降糖药,胰升糖素样肽1受体激动剂的血压效应日益受到重视。在动物研究中,急、慢性用药却表现出不同的血压效应;临床系列研究已肯定这类药物慢性用药的降压作用,不同药物降压效果无明显差异。脑干神经核团、心脏、肾脏、血管内皮细胞等,可能与其影响血压的作用机制有关。本文对胰升糖素样肽1及胰升糖素样肽1受体激动剂在动物和临床的血压效应及作用机制进行综述。

关键词：胰升糖素样肽1 胰升糖素样肽1受体胰升糖素样肽1受体激动剂血压

Linearization　Learning　Method　of　BP　Neural　Networks

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 1997年第1期2卷 37-41页

作者： Zhou Shaoqian ding lixin Zhang Jian Tang Xinhua Wuhan University State Key Laboratory of Software Engineering Wuhan China (GRID:grid.49470.3e) (ISNI:***) The Software Institute of Wuhan University Wuhan (GRID:grid.49470.3e) (ISNI:***)

Feedforward multi layer neural networks have very strong mapping capability that is based on the non linearity of the activation function, however, the non linearity of the activation function can cause the multiple local minima on the learning error surfaces, which affect the learning rate and solving optimal weights. This paper proposes a learning method linearizing non linearity of the activation function and discusses its merits and demerits theoretically.

关键词： BP neural networks activation function linearization method

在线全文

学校读者我要写书评

暂无评论

档案信息化的发展趋势

档案学研究 2009年第4期 12-14页

作者：丁立新东北大学档案馆 110004

档案信息化建设应立足于国家信息化战略高度。本文在分析我国档案信息化发展的机遇与困惑基础上,思考档案信息化发展的趋势,提出档案信息化工作模式走向协同化、项目化,档案信息化应用系统建设走向集成化、通用化,档案信息化运行维护走... 详细信息

档案信息化建设应立足于国家信息化战略高度。本文在分析我国档案信息化发展的机遇与困惑基础上,思考档案信息化发展的趋势,提出档案信息化工作模式走向协同化、项目化,档案信息化应用系统建设走向集成化、通用化,档案信息化运行维护走向专业化、平台化。

关键词：信息化资源共建资源共享