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民众科学运动的“资源谱图”——心和身的参与
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作者 刘健芝 《中国改革(农村版)》 2003年第6期44-45,共2页
印度喀拉拉邦的民众科学运动,在上个世纪六七十年代经历了艰难的摸索、挫折的阶段,在80年代末推行全民识字运动,在社区发动人们调查自然资源、人力资源,包括健康问题、贫穷问题等等,然后选取了十多个乡做试点,与乡民一起制订了民间的15... 印度喀拉拉邦的民众科学运动,在上个世纪六七十年代经历了艰难的摸索、挫折的阶段,在80年代末推行全民识字运动,在社区发动人们调查自然资源、人力资源,包括健康问题、贫穷问题等等,然后选取了十多个乡做试点,与乡民一起制订了民间的15年全面发展计划,包括如何利用本地资源,促进本地的生产和消费。本文作者刘健芝老师曾多次前往喀拉拉考察这一运动,下文对民众科学运动的“资源谱图”的描述,即为其考察报告之一。农村版自开设乡村建设专栏以来已多次刊发刘老师的考察印象,我们希望这系列系列文章能有所裨益于我国的农村建设。 展开更多
关键词 喀拉拉民众科学运动 印度 农民素质 社区建设 资源图” 资源保护
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土地是民生之本 发展是强市之路——西宁市国土资源局节约集约利用资源谱新篇
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《青海国土经略》 2015年第3期10-12,共3页
近年来,西宁市国土资源局在青海省国土资源厅党委和西宁市委、市政府领导下,紧紧围绕"保护资源更加严格规范、利用资源更加节约集约、维护群众权益更加有力有效"的工作要求和"积极主动服务、严格规范管理"的工作方... 近年来,西宁市国土资源局在青海省国土资源厅党委和西宁市委、市政府领导下,紧紧围绕"保护资源更加严格规范、利用资源更加节约集约、维护群众权益更加有力有效"的工作要求和"积极主动服务、严格规范管理"的工作方针,不断提高资源保障和管理、服务水平,为西宁市经济社会发展提供资源保障。严格土地利用总体规划和矿产资源规划管控,服务西宁经济社会发展随着西部大开发和城市工业化、城镇化的步伐加快,西宁市建设用地规模计划已基本用完。 展开更多
关键词 国土资源 资源 矿产资源规划 建设用地规模 城市工业化 生之本 社会经济 农用地转用 项目建设用地
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高原鼠兔与达乌尔鼠兔食物资源维生态位的研究 被引量:40
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作者 樊乃昌 景增春 张道川 《兽类学报》 CAS CSCD 北大核心 1995年第1期36-40,共5页
作者于1993年在青海省刚察县年诺索玛地区发现高原鼠兔(Ocholonacurzoniae)和达乌尔鼠兔(O.daurica)在布哈河谷二阶地同域且重叠分布之现象,并从这两种鼠兔的食物资源利用出发,研究了其生态位关系... 作者于1993年在青海省刚察县年诺索玛地区发现高原鼠兔(Ocholonacurzoniae)和达乌尔鼠兔(O.daurica)在布哈河谷二阶地同域且重叠分布之现象,并从这两种鼠兔的食物资源利用出发,研究了其生态位关系问题。在食物资源维上的生态位宽度(PS).高原鼠兔为0.4744.达乌尔鼠兔为0.4964,即它们具有相近似的生态位宽度。这两种动物的生态位在食物资源谱维上的重叠值(FT)为0.8091.表明它们在对食物资源的利用方面存在着激烈的竞争。 展开更多
关键词 鼠兔 高原鼠兔 达乌尔鼠兔 食物资源 草原
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AFLP Fingerprint and SCAR Marker of Watermelon Core Collection 被引量:31
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作者 车克鹏 许勇 +5 位作者 梁春阳 宫国义 翁曼丽 张海英 金德敏 王斌 《Acta Botanica Sinica》 CSCD 2003年第6期731-735,共5页
The identification of germplasm is an important step for effective utilization of the available germplasm. In previous studies, isoenzyme, RAPD and SSR techniques had been used to conduct the genetic identification of... The identification of germplasm is an important step for effective utilization of the available germplasm. In previous studies, isoenzyme, RAPD and SSR techniques had been used to conduct the genetic identification of watermelon ( Citrullus lanatus (Thunb.) Mansf.), but their effectiveness was limited due to the extremely narrow genetic background among watermelon genotypes. In this research, amplified fragment length polymorphism (AFLP), which was reported as a reliable technique with high efficiency in detecting polymorphism, was used to conduct genetic analysis and variety identification of thirty genotypes of watermelon core collection that represent a wide range of breeding and commercially available germplasm. As a result, a DNA fingerprint based on 15 bands amplified with four primer combinations was developed. In this fingerprint, each genotype has its unique fingerprint pattern and can be distinguished from each other. Furthermore, in or der to facilitate the utilization of AFLP marker in practice, one specific AFLP band of genotype 'PI296341' coming from fragment amplified by primer combination E-AT/M-CAT was successfully converted into a sequence characterized amplified region (SCAR) marker. 展开更多
关键词 AFLP variety identification FINGERPRINT SCAR WATERMELON
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试论应急无线电管理体制建设
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作者 郑维强 《中国无线电》 2009年第11期21-23,共3页
在各类突发事件发生后,及时、快速、准确地掌握信息,是各级政府正确应对和处置突发事件的必要条件。而无线电频率作为无线通信的唯一载体在应急无线电通信中是不可或缺的关键因素,因此,各级政府尽快完善和加强应急无线电管理体系的社会... 在各类突发事件发生后,及时、快速、准确地掌握信息,是各级政府正确应对和处置突发事件的必要条件。而无线电频率作为无线通信的唯一载体在应急无线电通信中是不可或缺的关键因素,因此,各级政府尽快完善和加强应急无线电管理体系的社会建设就显得十分重要。加强应急无线电管理能力,建立集中统一的应急无线电管理体制作为政府妥善应对和处置突发事件的重要条件和手段,一定能够在应对突发事件的社会实践中发挥越来越重要的作用。 展开更多
关键词 无线电频 谱资源 应急无线电管理 体制建设
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Power Control for Fading Channels in Cognitive Radio Networks with Outage-Probability Minimization 被引量:4
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作者 Luan Yu Li Hongzuo Wang Yafei 《China Communications》 SCIE CSCD 2012年第12期108-116,共9页
Cognitive radio allows Secondary Users (SUs) to dynamically use the spectrum resource licensed to Prirmry Users (PUs), and significantly improves the efficiency of spectrum utilization and is viewed as a promising... Cognitive radio allows Secondary Users (SUs) to dynamically use the spectrum resource licensed to Prirmry Users (PUs), and significantly improves the efficiency of spectrum utilization and is viewed as a promising technology. In cognitive radio networks, the problem of power control is an important issue. In this paper, we mainly focus on the problem of power control for fading channels in cognitive radio networks. The spectrum sharing underlay scenario is considered, where SUs are allowed to coexist with PUs on the condition that the outage probability of PUs is below the maximum outage probability threshold limitation due to the interference caused by SUs. Moreover, besides the outage probability threshold which is defined to protect the performance of PUs, we also consider the maximum transmit power constraints for each SU. With such a setup, we emphasize the problem of power control to minimize the outage probability of each SU in fading channels. Then, based on the statistical information of the fading channel, the closed expression for outage probability is given in fading channels. The Dual-Iteration Power Control (DIPC) algorithm is also proposed to minimize the outage probability based on Perron-Frobenius theory and gradient descent method under the constraint condition. Finally, simulation results are illustrated to demonstrate the performance of the proposed scheme. 展开更多
关键词 cognitive radio power control outage probability Perron-Frobenius theory fading channel
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Dynamic System Level Frequency Spectrum Allocation Scheme Based on Cognitive Radio Technology 被引量:2
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作者 WEI Zaixue YANG Dacheng SANG Lin 《China Communications》 SCIE CSCD 2014年第7期84-91,共8页
Cognitive radio is being widely discussed,and resource allocation scheme is drawing a lot of attention.Although the existed resource allocation strategies have successfully enhanced spectrum efficiency,some critical c... Cognitive radio is being widely discussed,and resource allocation scheme is drawing a lot of attention.Although the existed resource allocation strategies have successfully enhanced spectrum efficiency,some critical challenges still remain unanswered such as the jointly consideration of the efficiency and fairness,the rational description of the spectrum resources,and the execution mode of the spectrum allocation.This paper presents a system level dynamic frequency spectrum allocation scheme based on a central heterogeneous network architecture,evaluates the matching degree of the spectrum demand and the available spectrum resources with corresponding matrices,jointly considers the efficiency and fairness of different cognitive radio systems.Simulation results and the application scenario are also presented and analyzed. 展开更多
关键词 frequency spectrum allocationscheme heterogeneous network cognitiveradio spectrum resource manage center
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Dynamic overlapped spectrum allocation based on potential game in cognitive radio networks 被引量:1
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作者 贾亚男 Yue Dianwu 《High Technology Letters》 EI CAS 2014年第4期401-408,共8页
In order to make full use of wireless spectrum resources,the behavior of cognitive radio(CR)for dynamic spectrum allocation is analyzed based on the game theoretic framework.The traditional spectrum allocation schemes... In order to make full use of wireless spectrum resources,the behavior of cognitive radio(CR)for dynamic spectrum allocation is analyzed based on the game theoretic framework.The traditional spectrum allocation schemes consider the spectrum allocation among independent frequency bands only,without taking into account mutually overlapped frequency bands.For this reason,an optimal allocation etiquette is defined to promote the cross characteristic of the frequency bands in a dynamic spectrum allocation model.New interference operator and interference temperature constraints are introduced in order to realize calculation of the interference,and the corresponding spectrum allocation scenario can be further formulated as a potential game.Based on the characteristic of dynamic selection using the game theory and the interference avoidance rule of interference temperature,the robustness of CR networks is increased and the scenario is more suitable for the dynamic changing of actual wireless communication and energy saving communication systems.Simulation results show that the signal to interference and noise ratio(SINR) level can be significantly improved through the optimal allocation of any available spectrum.The utilization rate of spectrum and throughput of overall CR networks are increased by fully utilizing the spectrum resources in the dynamic spectrum allocation model. 展开更多
关键词 cognitive radio (CR) game theory spectrum allocation nash equilibrium
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A Kinetic Spectrophotometric Method for the Determination of Iron (Ⅲ) in Water Samples 被引量:7
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作者 JI Hongwei XU Jian XIN Huizhen YANG Xiaoman 《Journal of Ocean University of China》 SCIE CAS 2008年第2期161-165,共5页
A new kinetic spectrophotometric method has been developed for the determination of iron (Ⅲ). The method is based on the catalytic effect of iron (Ⅲ) on the oxidation of weak acid brilliant blue dye (RAWL) by ... A new kinetic spectrophotometric method has been developed for the determination of iron (Ⅲ). The method is based on the catalytic effect of iron (Ⅲ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The advantages of the proposed method are that it is sensitive, accurate, rapid, inexpensive, can be operated under room temperature and has a large determination concentration range compared to other techniques. The obtained optimum conditions are: pH 3.15, RAWL (200 mgL^-1) 5.00mL, Potassium periodate solution (0.01 molL^-1) 0.30mL, phenanthroline (0.02 molL^-1) 1.00mL, reaction temperature 25℃ and reaction time 7 min. With this method iron could quantitively be determined in the range 0.00-0.02 mgL^-1, the detection limit being 4.10 × 10^10gmL^-1. The relative standard deviations (RSD) in five replicate determinations for 3 μgL^-1and 5 μgL^-1 iron (Ⅲ) are 3.1% and 1.9%, respectively. The method has been applied to the determination of iron (Ⅲ) in tap water samples and seawater samples (from the South China Sea), the recovery rates being 98.0% and 100.5%, respectively. 展开更多
关键词 IRON kinetic spectrophotometry catalytic effect weak acid brilliant blue dye (RAWL)
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Energy Efficiency-Based Decision Making in Cognitive Radio Networks
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作者 Hongning Li Qingqi Pei Leilei Xu 《China Communications》 SCIE CSCD 2016年第11期205-213,共9页
As a constraint for smart devices,energy consumption has attract people's attention for a long time period. How to get higher resource utilization with less energy consumption is a challenge for cognitive radio ne... As a constraint for smart devices,energy consumption has attract people's attention for a long time period. How to get higher resource utilization with less energy consumption is a challenge for cognitive radio networks. Secondary users have to participate in spectrum sensing at the cost of energy and access idle spectrum without interfering primary users. However,not all participating secondary users can access idle spectrum. How to ensure the participation users access spectrum efficiently with a larger probability is an urgent problem to be solved. We propose an Energy Efficiency-based Decision Making(EEDM) for cognitive radio networks,which fully considers residual energy and probability of obtaining spectrum resources. Simulation and analysis show that the proposed scheme can maximize proportion of allocated users under the premise of ensuring the accuracy of spectrum sensing,then balance users' energy consumption and access efficiency,so as to effectively improve the utilization of spectrum resources. 展开更多
关键词 cognitive radio networks spectrum sensing energy efficiency decision making
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A novel spectrum borrowing scheme in integrated 3G/WLAN networks
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作者 李希金 Ji Hong Zhang Lin 《High Technology Letters》 EI CAS 2012年第2期155-159,共5页
In the heterogeneous wireless networks of the next generation, a large number of different radio access technologies will be integrated into a common network. This paper considers optimizing the utilization of spectru... In the heterogeneous wireless networks of the next generation, a large number of different radio access technologies will be integrated into a common network. This paper considers optimizing the utilization of spectrum resource in heterogeneous environment consisting two different networks: wireless local area network (WLAN) and time division-synchronous code division multiple access (TD-SCDMA) network. An optimal joint spectrum borrowing scheme maximizing overall network revenue is proposed with quality of service (QoS) constraints over both the WLAN and the TD-SCDMA cellular networks. Simulation results illustrate that system revenue earned in the proposed joint spectrum borrowing scheme is significantly larger than the case when individual networks are optimized independently. 展开更多
关键词 heterogeneous wireless network integrated network spectrum borrowing
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Digital Dividend: The Path Towards Business and Marketing Development
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作者 George Mastorakis 《Chinese Business Review》 2011年第12期1131-1137,共7页
Wireless radio spectrum is an important resource that allows for increased business development, throtigh the provision of services using wireless networking infrastructures. Since radio spectrum is limited, an optima... Wireless radio spectrum is an important resource that allows for increased business development, throtigh the provision of services using wireless networking infrastructures. Since radio spectrum is limited, an optimal utilization of it is required, by adopting advanced spectrum management methods. The current transition from analogue to digital terrestrial television may act as a unique opportunity, in order to reallocate this valuable spectrum resource. After the transition, a part of the traditional analogue television spectrum bands will be completely released, allowing for the use of this spectrum by sophisticated wireless systems. Furthermore, digital terrestrial television interleaves spectrum bands in order to avoid possible interference between adjacent channels used by broadcasting stations, thus leaving spectrum holes exploited by novel wireless networks, namely unlicensed secondary systems. In this context, this article investigates business and marketing development issues, arising by utilizing released and interleaved television spectrum bands 展开更多
关键词 radio spectrum digital dividend business and marketing development
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Analysis and Modeling of k-regular and k-connected Protection Structure in Ultra-High Capacity Optical Networks
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作者 LI Xin HUANG Shanguo +3 位作者 ZHANG Jie ZHAO Yongli GU Wanyi WANG Yang 《China Communications》 SCIE CSCD 2015年第3期106-119,共14页
This paper proposes k-regular and k-connected(k&k) structure against multifaults in ultra-high capacity optical networks.Theoretical results show that pre-configured k&k structure can reach the lower bound on ... This paper proposes k-regular and k-connected(k&k) structure against multifaults in ultra-high capacity optical networks.Theoretical results show that pre-configured k&k structure can reach the lower bound on logical redundancy.The switching time of k&k protection structure is as quickly as ringbased protection in SDH network.It is the optimal protection structure in ultra-high capacity optical networks against multi-faults.We develop the linear programming model for k&k structure and propose a construction method for k&k structure design.Simulations are conducted for spare spectrum resources effi ciency of the pre-confi gured k&k structure under multi-faults on representative COST239 and NSFnet topologies.Numerical results show that the spare spectrum resources efficiency of k&k structure can reach the lower bound on logical redundancy in static networks.And it can largely improve spare spectrum resources effi ciency compared with p-cycles based protection structure without reducing protection effi ciency under dynamic traffi cs. 展开更多
关键词 multi-faults k-regular and k-connected structure ultra-high capacity optical networks
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An Enhanced Spectrum Resource Allocation Algorithm in Hetnets
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作者 ZHAO Linjing ZHAO Huaying HUO Guangrui 《China Communications》 SCIE CSCD 2015年第10期182-192,共11页
Efficient spectrum resource allocation in wireless heterogeneous networks is important for improving the system throughput and guaranteeing the user's Quality-of-Service(QoS).In this paper,we propose an enhanced a... Efficient spectrum resource allocation in wireless heterogeneous networks is important for improving the system throughput and guaranteeing the user's Quality-of-Service(QoS).In this paper,we propose an enhanced algorithm for spectrum resource allocation in heterogeneous networks.First,the bandwidth of each user is determined by the user's rate demand and the channel state.Second,graph theory is enhanced and used to improve the spectrum efficiency.Third,spectrum resource is dynamically split between macrocell and femtocells with the changes of users' conditions.Our simulation results show that the proposed algorithm improves the system throughput significantly and also guarantees the fairness for the users. 展开更多
关键词 resource management heterogeneous networks graph theory throughput fairness
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Snow Cover Variation and Streamflow Simulation in a Snow-fed River Basin of the Northwest Himalaya 被引量:5
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作者 Vaibhav SHARMA V.D.MISHRA P.K.JOSHI 《Journal of Mountain Science》 SCIE CSCD 2012年第6期853-868,共16页
Snowmelt is an important component of any snow-fed river system.The Jhelum River is one such transnational mountain river flowing through India and Pakistan.The basin is minimally glacierized and its discharge is larg... Snowmelt is an important component of any snow-fed river system.The Jhelum River is one such transnational mountain river flowing through India and Pakistan.The basin is minimally glacierized and its discharge is largely governed by seasonal snow cover and snowmelt.Therefore,accurate estimation of seasonal snow cover dynamics and snowmeltinduced runoff is important for sustainable water resource management in the region.The present study looks into spatio-temporal variations of snow cover for past decade and stream flow simulation in the Jhelum River basin.Snow cover extent(SCE) was estimated using MODIS(Moderate Resolution Imaging Spectrometer) sensor imageries.Normalized Difference Snow Index(NDSI) algorithm was used to generate multi-temporal time series snow cover maps.The results indicate large variation in snow cover distribution pattern and decreasing trend in different sub-basins of the Jhelum River.The relationship between SCE-temperature,SCE-discharge and discharge-precipitation was analyzed for different seasons and shows strong correlation.For streamflow simulation of the entire Jhelum basin Snow melt Runoff Model(SRM) used.A good correlation was observed between simulated stream flow and in-situ discharge.The monthly discharge contribution from different sub-basins to the total discharge of the Jhelum River was estimated using a modified version of runoff model based on temperature-index approach developed for small watersheds.Stream power - an indicator of the erosive capability of streams was also calculated for different sub-basins. 展开更多
关键词 Snow cover extent(SCE) Streamflow Snow Melt Runoff Model(SRM) Normalized Difference Snow Index(NDSI) Jhelum basin Moderate Resolution Imaging Spectrometer(MODIS)
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Fruit Waste and Sugarcane Bagasse as Potential Natural Resources of Mineral and Lipophilic Substances
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作者 Sonia Patricia Ordonez Crispin Humberto Garcia-Cruz +1 位作者 Mauricio Boscolo Jesus Eliecer Larrahondo 《Journal of Food Science and Engineering》 2015年第3期137-141,共5页
The objectives of this study were to explore alternatives for using fruit waste and sugarcane bagasse as important sources for new products and potential applications in the food industry. Fast foods are part of moder... The objectives of this study were to explore alternatives for using fruit waste and sugarcane bagasse as important sources for new products and potential applications in the food industry. Fast foods are part of modern life, as well as sources for producing biofuels based on biomass. The mineral content and compounds of nutritional interest, such as lipophilic substances, were determined in fruit waste (orange peels, passion fruit, bananas, grapes) and sugarcane bagasse. Significant differences were found in the samples tested, where minerals, such as potassium, nitrogen, zinc and iron, were found in fruit residues (bananas, oranges, passion fruit) and sugarcane bagasse. Banana residues were the most important source of minerals, followed by orange peels. Gas chromatography mass spectrography (GC-MS) analyses of the lipophilic fractions obtained from the plant residues revealed the presence of mostly saturated (palmitic, stearic) and unsaturated (oleic and linoleic) fatty acids, as well as other nutritionally valuable compounds, such as antioxidants (flavones in orange residues). The residues studied here can be used for future research to optimize pretreatment and hydrolysis of biomass for bioethanol production. 展开更多
关键词 BIOMASS fruit waste MINERALS lipophilic substances sugarcane bagasse
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Achieving fairness by aggregate power allocation in opportunistic cooperation networks
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作者 曹建飞 Zhong +2 位作者 Zhangdui, Ai Bo 《High Technology Letters》 EI CAS 2009年第3期309-314,共6页
Within a wireless opportunistic network,one of the lucky users gets an opportunity to utilize thewhole radio resource.However some of the unlucky users keep silent during an unexpected period result-ing from severe wi... Within a wireless opportunistic network,one of the lucky users gets an opportunity to utilize thewhole radio resource.However some of the unlucky users keep silent during an unexpected period result-ing from severe wireless environment and imperfect scheduling algorithms .An opportunistic cooperationprotocol is proposed that can achieve equivalent performance measured in terms of outage probability,inwhich scheme the opportunistic user helps to relay what need retransmitting indicated by the destinationand selects the appropriate power allocation to pursue fairness.The proposed scheme deploys superposi-tion coding and successive interference cancellation at relay and destination,respectively .To improve thespectral efficiency,the modified cooperation architecture involves two opportunistic users which work inturn.The simulation results demonstrate that the protocol obtains better performance compared with theconventional methods. 展开更多
关键词 opportunistic communication cooperation diversity FAIRNESS superposition coding
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The remote sensing inversion theory of offshore oil slick thickness based on a two-beam interference model 被引量:11
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作者 LU YingCheng TIAN QingJiu LI Xiang 《Science China Earth Sciences》 SCIE EI CAS 2011年第5期678-685,共8页
Offshore oil slicks are significant for both the monitoring of marine spill accidents and the detection of marine oil resources.The use of remote sensing technology to detect the thickness of oil slicks is a major are... Offshore oil slicks are significant for both the monitoring of marine spill accidents and the detection of marine oil resources.The use of remote sensing technology to detect the thickness of oil slicks is a major area of research.The reflected light from oil slicks changes with the thickness of the oil.This is the theoretical basis of research on optical remote sensing of offshore oil slicks.A two-beam interference model that considers the offshore oil slick as a flat plate has been developed in this study.A quantitative remote sensing model which describes a series of processes that use oil slick thickness and reflectance as variables is established.The use of the Fresnel equation to analyze parameters in the model indicated that the key property of the quantitative relationship between the oil slick thickness and reflectance was ultimately the disappearance or extinction of the oil slick.This model has been tested and verified by data from offshore oil slick spectral response experiments.Results showed that the oil slick thickness remote sensing model can be theoretically analyzed and is efficient.The research indicated that the major cause of variations in the spectral response as a function of oil slick thickness was the different light-scattering characteristics.These characteristics can be used in remote sensing applications to identify the different types of offshore oil slicks.The theoretical interpretation of each parameter in this model led to the development of a look-up table of the model parameters which will improve the efficiency of future offshore oil slick remote sensing. 展开更多
关键词 two-beam interference oil slick thickness remote sensing reflectance
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