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南京市森林特点与环市自然保护区网的建设 被引量:5
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作者 黄致远 宗世贤 朱小毅 《江苏林业科技》 2000年第3期20-24,共5页
在分析研究了南京市的自然环境、植物区系与森林类型特点的基础上提出了建设南京市环市森林公园型自然保护区网的建议 ,讨论了各保护区的保护内容。
关键词 南京市 自然保护区 植物区网 森林类型
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巷道区网模拟中传导换热模型的修正
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作者 邢书仁 吴兵 《煤炭学报》 EI CAS CSCD 北大核心 2007年第2期177-180,共4页
为提高巷道网络火灾计算机模拟的准确性,进一步完善巷道火灾计算机模型,采用理论分析和数值计算方法,以巷道火灾网络模拟技术为基础,充分利用区域模拟基本思想和建筑多室火灾区域模拟的主体控制模型,以及该模型可以增添和修改火灾分过... 为提高巷道网络火灾计算机模拟的准确性,进一步完善巷道火灾计算机模型,采用理论分析和数值计算方法,以巷道火灾网络模拟技术为基础,充分利用区域模拟基本思想和建筑多室火灾区域模拟的主体控制模型,以及该模型可以增添和修改火灾分过程模型的开放性特点,分析应用对象的初始及边界条件,对其中传导换热模型进行了必要的修正,重新解算了火源巷道中风流或烟流温度的方程式,并对模型进行了验证. 展开更多
关键词 区网模拟 传导换热模型 巷道火灾
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网站推介
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作者 高璟 《国外城市规划》 2005年第3期91-91,共1页
可持续住区网,美国精明增长合作组织网。
关键词 网站 可持续住区网 美国精明增长合作组织 信息交流
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PARALLEL COMPUTATION OF 3-D HYPERSONIC FLOWS ON UNSTRUCTURED HYBRID MESHES 被引量:3
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作者 王江峰 伍贻兆 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第3期200-205,共6页
A parallel virtual machine (PVM) protocol based parallel computation of 3-D hypersonic flows with chemical non-equilibrium on hybrid meshes is presented. The numerical simulation for hypersonic flows with chemical n... A parallel virtual machine (PVM) protocol based parallel computation of 3-D hypersonic flows with chemical non-equilibrium on hybrid meshes is presented. The numerical simulation for hypersonic flows with chemical non-equilibrium reactions encounters the stiffness problem, thus taking huge CPU time. Based on the domain decomposition method, a high efficient automatic domain decomposer for three-dimensional hybrid meshes is developed, and then implemented to the numerical simulation of hypersonic flows. Control equations are multicomponent N-S equations, and spatially discretized scheme is used by a cell-centered finite volume algorithm with a five-stage Runge-Kutta time step. The chemical kinetic model is a seven species model with weak ionization. A point-implicit method is used to solve the chemical source term. Numerical results on PC-Cluster are verified on a bi-ellipse model compared with references. 展开更多
关键词 hypersonic speed hybrid mesh domain decomposition PARALLELIZATION
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河南省城市社区卫生服务利用现状 被引量:5
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作者 李莹 周刚 +4 位作者 朱宝玉 张智民 郑旗 陈建设 冯石献 《中国慢性病预防与控制》 CAS 2008年第2期194-195,共2页
目的了解河南省城市社区慢性病监测网络中高血压、糖尿病患者对社区卫生服务的利用情况。方法对河南省城市社区慢性病监测试点的高血压、糖尿病患者进行面对面问卷调查。结果1/3以上的高血压、糖尿病管理患者将社区作为知识获取的第一途... 目的了解河南省城市社区慢性病监测网络中高血压、糖尿病患者对社区卫生服务的利用情况。方法对河南省城市社区慢性病监测试点的高血压、糖尿病患者进行面对面问卷调查。结果1/3以上的高血压、糖尿病管理患者将社区作为知识获取的第一途径;对社区卫生服务基本满意率为92.9%;6个月内到社区就诊率平均为64.6%;86.0%的高血压患者和54.1%糖尿病患者能做到1月内定期测量血压和检测血糖;60%的管理患者选择社区就诊;80.03%以上的管理患者接受了药物性治疗,有56.7%~82.3%的管理患者接受了非药物性治疗服务。结论要积极推广社区高血压、糖尿病综合防控适宜技术,加强患者规范管理,提升社区卫生服务能力,促进居民对社区卫生服务的利用。 展开更多
关键词 监测点 高血压 糖尿病 社区卫生服务 网络管理
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N-S EQUATION CALCULATIONS ON MULTI-ELEMENT AIRFOILS WITH ZONAL PATCHED GRIDS 被引量:2
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作者 郭同庆 陆志良 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期155-158,共4页
For a complex flow about multi-element airfoils a mixed grid method is set up. C-type grids are produced on each element′s body and in their wakes at first, O-type grids are given in the outmost area, and H-type grid... For a complex flow about multi-element airfoils a mixed grid method is set up. C-type grids are produced on each element′s body and in their wakes at first, O-type grids are given in the outmost area, and H-type grids are used in middle additional areas. An algebra method is used to produce the initial grids in each area. And the girds are optimized by elliptical differential equation method. Then C-O-H zonal patched grids around multi-element airfoils are produced automatically and efficiently. A time accurate finite-volume integration method is used to solve the compressible laminar and turbulent Navier-Stokes (N-S) equations on the grids. Computational results prove the method to be effective. 展开更多
关键词 multi-element airfoils zonal patched grids finite-volume method N-S equations
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A Gridless Router Based on Hierarchical PB Corner Stitching Structure
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作者 张轶谦 蔡懿慈 +2 位作者 洪先龙 张雁 谢民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第2期141-147,共7页
A multi layer gridless area router is reported.Based on corner stitching,this router adopts tile expansion to explore path for each net.A heuristic method that penalizes nodes deviating from the destination is devise... A multi layer gridless area router is reported.Based on corner stitching,this router adopts tile expansion to explore path for each net.A heuristic method that penalizes nodes deviating from the destination is devised to accelerate the algorithm.Besides,an enhanced interval tree is used to manage the intermediate data structure.In order to improve the completion rate of routing,a new gridless rip up and rerouting algorithm is proposed.The experimental results indicate that the completion rate is improved after the rip up and reroute process and the speed of this algorithm is satisfactory. 展开更多
关键词 gridless area routing rip up and reroute corner stitching structure VLSI
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Optimization method for evacuation zone with network reconfiguration based on dynamic simulation 被引量:1
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作者 赵星 任刚 +1 位作者 张小丽 李岩 《Journal of Southeast University(English Edition)》 EI CAS 2016年第3期373-378,共6页
Abstract: With a determinate danger zone and evacuation demand caused by an emergency, an optimization method for the evacuation zone with network reconfiguration based on dynamic simulation is proposed. The method c... Abstract: With a determinate danger zone and evacuation demand caused by an emergency, an optimization method for the evacuation zone with network reconfiguration based on dynamic simulation is proposed. The method contains three modules. First, the network in the evacuation zone is optimized by a model with the integrated strategy of lane reversal and intersection conflict elimination. Secondly, the dynamic evacuation simulation model based on the cell transmission model is applied to simulate the dynamic propagation process of evacuated vehicles in the network in the evacuation zone. The evacuation time for all evacuated vehicles leaving the danger zone is obtained and the setting of the current evacuation zone is fed back. Thirdly, the arrival distributions of evacuated vehicles at critical intersections of the evacuation zone are also obtained to estimate the delay at critical intersection to determine whether the intersection should be taken as the critical intersection in the next iteration. The evacuation zone is expanded gradually through iteration, and the reasonable evacuation zone and the optimal evacuation network is confirmed. Based on the survey of the parking lot and urban street network around Nanjing Olympic Sports Center, the models and the iterative algorithm were applied to obtain the optimal plan of the evacuation zone with network reconfiguration in an evacuation situation to verify the validity of the proposed method. 展开更多
关键词 evacuation zone cell transmission model traffic network reconfiguration intersection delay
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Application of multiple attributes fusion technology in the Su-14 Well Block 被引量:2
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作者 王兴建 胡光岷 曹俊兴 《Applied Geophysics》 SCIE CSCD 2010年第3期257-264,293,共9页
In this study area the geological conditions are complicated and the effective sandstone is very heterogeneous.The sandstones are thin and lateral and vertical variations are large.We introduce multi-attribute fusion ... In this study area the geological conditions are complicated and the effective sandstone is very heterogeneous.The sandstones are thin and lateral and vertical variations are large.We introduce multi-attribute fusion technology based on pre-stack seismic data, pre-stack P-and S-wave inversion results,and post-stack attributes.This method not only can keep the fluid information contained in pre-stack seismic data but also make use of the high SNR characteristics of post-stack data.First,we use a one-step recursive method to get the optimal attribute combination from a number of attributes.Second,we use a probabilistic neural network method to train the nonlinear relationship between log curves and seismic attributes and then use the trained samples to find the natural gamma ray distribution in the Su-14 well block and improve the resolution of seismic data.Finally,we predict the effective reservoir distribution in the Su-14 well block. 展开更多
关键词 multiple attributes fusion neural network interactive validation Su-14 well block
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论新闻媒体的社区化生存之路——以深圳报业集团为例
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作者 叶梅 《现代视听》 2014年第8期73-76,共4页
近年来,传统报业在"严冬"中迅速消亡论引起业界和学界的瞩目,不同的新闻从业人员和学者对"报业寒冬论"也有着不同的见解。其实,传统新闻媒体虽然一直承受着巨大压力,但是笔者认为传统新闻媒体仍有顽强的生命力。
关键词 社区报 区网 社区化媒体
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Evaluating Conservation Effectiveness of Nature Reserves Established for Surrogate Species:Case of a Giant Panda Nature Reserve in Qinling Mountains,China 被引量:12
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作者 XU Weihua Andrés VIA +4 位作者 QI Zengxiang OUYANG Zhiyun LIU Jianguo LIU Wei WAN Hui 《Chinese Geographical Science》 SCIE CSCD 2014年第1期60-70,共11页
Many nature reserves are established to protect the habitat needs of particular endangered species of interest but their effectiveness for protecting other species is questionable.In this study,this effectiveness was ... Many nature reserves are established to protect the habitat needs of particular endangered species of interest but their effectiveness for protecting other species is questionable.In this study,this effectiveness was evaluated in a nature reserve network located in the Qinling Mountains,Shaanxi Province,China.The network of reserves was established mainly for the conservation of the giant panda,a species considered as a surrogate for the conservation of many other endangered species in the region.The habitat suitability of nine protected species,including the giant panda,was modeled by using Maximum Entropy(MAXENT)and their spatial congruence was analyzed.Habitat suitability of these species was also overlapped with nature reserve boundaries and their management zones(i.e.,core,buffer and experimental zones).Results show that in general the habitat of the giant panda constitutes a reasonable surrogate of the habitat of other protected species,and giant panda reserves protect a relatively high proportion of the habitat of other protected species.Therefore,giant panda habitat conservation also allows the conservation of the habitat of other protected species in the region.However,a large area of suitable habitat was excluded from the nature reserve network.In addition,four species exhibited a low proportion of highly suitable habitat inside the core zones of nature reserves.It suggests that a high proportion of suitable habitat of protected species not targeted for conservation is located in the experimental and buffer zones,thus,is being affected by human activities.To increase their conservation effectiveness,nature reserves and their management zones need to be re-examined in order to include suitable habitat of more endangered species.The procedures described in this study can be easily implemented for the conservation of many endangered species not only in China but in many other parts of the world. 展开更多
关键词 giant panda habitat suitability Maximum Entropy(MAXENT) nature reserve network surrogate species
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Diurnal variation of phytoplankton community in a high frequency area of HABs: Daya Bay, China 被引量:3
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作者 刘华雪 宋星宇 +3 位作者 黄良民 钟瑜 沈萍萍 秦耿 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期800-806,共7页
Phytoplankton community was investigated in the cage culture area of Daya Bay during a diurnal cycle. Two rainfalls occurred during the course of the experiment and decreased the surface seawater salinity in the aquac... Phytoplankton community was investigated in the cage culture area of Daya Bay during a diurnal cycle. Two rainfalls occurred during the course of the experiment and decreased the surface seawater salinity in the aquaculture area. A total of 38 species were identified, of which the dominant species included Pseudo-nitzschia spp. and Skeletonema costatum. Water stratification obstructed the vertical migration of dinoflagellates. Statistical analysis indicated that Synechococcus showed negative relationship with silicate and ammonia, which indicated that Synechococcus adapted to grow at oligotrophic environment. Phytoplankton community structure implied the risk of Pseudo-nitzschia spp. blooms in the aquaculture area of Daya Bay. 展开更多
关键词 diurnal variation PHYTOPLANKTON aquaculture area Daya Bay
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GA and PSO culled hybrid technique for economic dispatch problem with prohibited operating zones 被引量:4
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作者 SUDHAKARAN M. AJAY-D-VIMALRAJ P. PALANIVELU T.G. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第6期896-903,共8页
This paper presents an efficient and reliable genetic algorithm (GA) based particle swarm optimization (PSO) tech- nique (hybrid GAPSO) for solving the economic dispatch (ED) problem in power systems. The non-linear c... This paper presents an efficient and reliable genetic algorithm (GA) based particle swarm optimization (PSO) tech- nique (hybrid GAPSO) for solving the economic dispatch (ED) problem in power systems. The non-linear characteristics of the generators, such as prohibited operating zones, ramp rate limits and non-smooth cost functions of the practical generator operation are considered. The proposed hybrid algorithm is demonstrated for three different systems and the performance is compared with the GA and PSO in terms of solution quality and computation efficiency. Comparison of results proved that the proposed algo- rithm can obtain higher quality solutions efficiently in ED problems. A comprehensive software package is developed using MATLAB. 展开更多
关键词 Economic dispatch (ED) Genetic algorithm (GA) Particle swarm optimization (PSO) Hybrid GAPSO Prohibited operating zone CROSSOVER MUTATION Velocity
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The social determinants of health influencing obesity for the aged in the Pakpoon community context:A qualitative study 被引量:1
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作者 Pornchanuch Chumpunuch Urai Jaraeprapal 《International Journal of Nursing Sciences》 CSCD 2022年第2期211-221,I0007,共12页
Objective:This study aimed to describe the social determinants of health influencing obesity for the aged in a community context and based on the perspectives of various stakeholders.Methods:This was qualitative conte... Objective:This study aimed to describe the social determinants of health influencing obesity for the aged in a community context and based on the perspectives of various stakeholders.Methods:This was qualitative content analysis study using data from the focus group,individual in-depth interview,and observation.The study population was domiciled in Pakpoon Village,Mung Dis-trict,Nakhon Si Thammarat Province,a tight-knit settlement typical of most retirement communities.Data were collected through two focus group discussions,direct observation,and in-depth interviews with 19 participants.Respondents represented key community groups:local nurses and public health officers,elderly residents,family caregivers(family members),and village health volunteers.Results:The participants shared similar perspectives about the social determinants of health influencing obesity in the aged,which spanned three themes.These were:1)neighborhood food environment(easy access to unhealthy food,no choice to recruit healthy food);2)social networks influencing obesity(family affects food choices and prohibitions on exercise;belief,and socially imposed body image per-ceptions contributing to obesity in the aged);and 3)knowledge,attitudes,and beliefs behind lifestyle choices that cause obesity in the elderly(lack of awareness,personal attitudes,job and familial duties as barriers to engaging in physical activities;over-consumption behaviors lead to obesity in older people).Conclusion:These three themes were the root causes of obesity in the elderly in Pakpoon’s retirement community.This finding suggests that policymakers and nurses can create healthy environments,both to treat and prevent obesity,by raising awareness in younger generations,providing aging the provision of healthy food choices for older adults,encouraging health care professionals to share knowledge,and by modifying the attitudes and beliefs of both caregivers and older adults. 展开更多
关键词 Aged Community networks Health services OBESITY Qualitative research Social behavior
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A New Scheme of Integrating NAS with SAN 被引量:3
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作者 王志恒 白英彩 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第1期6-9,共4页
This paper reviewed two types of network storage technique: NAS and SAN. After comparing and analyzing, it concluded that the ultimate realization of network storage will be in the eventual convergence of NAS and SAN ... This paper reviewed two types of network storage technique: NAS and SAN. After comparing and analyzing, it concluded that the ultimate realization of network storage will be in the eventual convergence of NAS and SAN architectures. Currently, all the integration methods are based on the architecture level. This paper presented a device level integration scheme based on IXP1200 network processor. The device can be used as an NAS file server or an SAN’s storage node. Furthermore, it can be used as a bridge to connect NAS and SAN, and then be shared by their clients. 展开更多
关键词 network attached storage (NAS) storage area network (SAN) network processor
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Performance analysis of an iSCSI-based unified storage network 被引量:2
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作者 傅湘林 张琨 谢长生 《Journal of Zhejiang University Science》 EI CSCD 2004年第1期1-7,共7页
In this paper, we introduced a novel storage architecture 'Unified Storage Network', which merges NAC( Network Attached Channel) and SAN( Storage Area Network) , and provides the file I/O services as NAS devic... In this paper, we introduced a novel storage architecture 'Unified Storage Network', which merges NAC( Network Attached Channel) and SAN( Storage Area Network) , and provides the file I/O services as NAS devices and provides the block I/O services as SAN. To overcome the drawbacks from FC, we employ iSCSI to implement the USN( Unified Storage Network) . To evaluate whether iSCSI is more suitable for implementing the USN, we analyze iSCSI protocol and compare it with FC protocol from several components of a network protocol which impact the performance of the network. From the analysis and comparison, we can conclude that the iSCSI is more suitable for implementing the storage network than the FC under condition of the wide-area network. At last, we designed two groups of experiments carefully. 展开更多
关键词 ISCSI Network Attached Channel (NAC) Unified Storage Networks (USN) NAS (Network Attached Storage) SAN (Storage Area Network)
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RESEARCH ON IMPERFECTION SENSITIVE REGION OF SINGLE-LAYER LATTICED DOMES
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作者 唐敢 王法武 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第4期243-249,共7页
The concept of the imperfection sensitive region is given. The advanced stochastic imperfection method is used to research the imperfection sensitive region of single-layer latticed domes. Taking a K6 single-layer lat... The concept of the imperfection sensitive region is given. The advanced stochastic imperfection method is used to research the imperfection sensitive region of single-layer latticed domes. Taking a K6 single-layer latticed dome with a diameter of 50 m as an example, its imperfection sensitive region is made up of the first 12 kinds of joints. The influence of the imperfections of support joints on the stability of the K6 single-layer latticed dome is negligible. Influences of the joint imperfections of the main rib and the secondary rib on the structural stability are similar. The initial deviations of these joints all greatly lower the critical load of the dome. Results show that the method can analyze the structural imperfection sensitive region quantitatively and accurately. 展开更多
关键词 IMPERFECTION single-layer latticed dome imperfection sensitive region advanced stochastic imperfection method critical load
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Effects of Forest Roads on Habitat Pattern for Sables in Da Hinggan Mountains, Northeasten China 被引量:4
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作者 LI Yuehui WU Wen +3 位作者 XIONG Zaiping HU Yuanman CHANG Yu XIAO Duning 《Chinese Geographical Science》 SCIE CSCD 2014年第5期587-598,共12页
The anthropogenic managements of forest have created a network of roads resulting in the loss and alternation of habitat. To better understand road′s impact on animal habitats, we assessed the habitat pattern of sabl... The anthropogenic managements of forest have created a network of roads resulting in the loss and alternation of habitat. To better understand road′s impact on animal habitats, we assessed the habitat pattern of sables(Martes zibellina), one of rodents within national first-class protected species, when roads are considered in Huzhong area in Da Hinggan Mountains, northeastern China. Employing published literatures about behavior ecology, aerial photographs and forest stand maps, we classified the study area into three habitat types including best-suitable, suitable and unsuitable habitats based on sable habitat requirements at the landscape scale including four variables derived from forest source map with attribute database. Results indicated the loss and significant fragmentation of best-suitable habitat and home range habitat when roads, especially 150 m avoidance distance of roads, were considered. The roads reduced and fragmented highly suitable habitats more significantly during earlier development period than the later development period. Additionally, the suitable area percentage increased with increasing distance to roads. This study helped to identify the suitable area for sables and location of sable population. Also, this study suggested the passage construction and road management involving road closure and removal will reduce the fragmentation functionally and benefit the sable population. 展开更多
关键词 forest road SABLE habitat pattern buffer analysis Da Hinggan Mountains
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Power Allocation for Energy Harvesting in Wireless Body Area Networks 被引量:1
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作者 Xiaolan Liu Fengye Hu +2 位作者 Meiqi Shao Dan Sui Gengxin He 《China Communications》 SCIE CSCD 2017年第6期22-31,共10页
Wireless Body Area Networks(WBANs) are expected to achieve high reliable communications among a large number of sensors.The outage probability can be used to measure the reliability of the WBAN.In this paper,we optimi... Wireless Body Area Networks(WBANs) are expected to achieve high reliable communications among a large number of sensors.The outage probability can be used to measure the reliability of the WBAN.In this paper,we optimize the outage probability with the harvested energy as constraints.Firstly,the optimal transmit power of the sensor is obtained while considering a single link between an access point(AP) located on the waist and a sensor attached on the wrist over the Rayleigh fading channel.Secondly,an optimization problem is formed to minimize the outage probability.Finally,we convert the non-convex optimization problem into convex solved by the Lagrange multiplier method.Simulations show that the optimization problem is solvable.The outage probability is optimized by performing power allocation at the sensor.And our proposed algorithm achieves minimizing the outage probability when the sensor uses energy harvesting.We also demonstrate that the average outage probability is reduced with the increase of the harvested energy. 展开更多
关键词 wireless body area networks(WBANs) outage probability energy harvesting RELIABILITY
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Energy-efficient Medium Access Approach for Wireless Body Area Network Based on Body Posture 被引量:1
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作者 WANG Feng HU Fengye +3 位作者 WANG Lu DU Yu LIU Xiaolan GUO Gang 《China Communications》 SCIE CSCD 2015年第12期122-132,共11页
Energy efficiency has become one of the most important issues in wireless body area network(WBAN).In this paper,an energy-efficient medium access control(MAC)protocol for WBAN is proposed based on human body posture u... Energy efficiency has become one of the most important issues in wireless body area network(WBAN).In this paper,an energy-efficient medium access control(MAC)protocol for WBAN is proposed based on human body posture under walking scenery.Due to person's movements,WBAN is a dynamic network,which means that traditional static protocols are no more suitable for it.For solving this problem,firstly,the feature of human walking at a constant speed is analyzed and we divide a spell of movements into a sequence of key frames just like a video constituted by numbers of continuous frames.As a result,the dynamic walking process is translated into several static postures,which the static MAC protocol could be used for.Secondly,concerning the performance of network lifetime,we design a posture-aware approach for lifetime maximization(PA-DPLM).With analytical and simulation results provided,we demonstrate that PA-DPLM protocol is energy-efficient and can be used under constant speed walking scenery. 展开更多
关键词 Medium lifetime aware frames maximization walking transmit topology gains beacon
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