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时变AGV小车多物流任务配送路线实时SCA优化算法
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作者 黄继磊 卢胜勇 吴奔 《包装工程》 北大核心 2026年第1期226-231,共6页
目的解决时变AGV小车多物流任务配送路线的平均配送时间较长的问题。方法提出一种时变AGV小车多物流任务配送路线的实时正弦余弦算法(Sine Cosine Algorithm,SCA)。通过建立车辆运输动态模型,求解配送时效性与关键参数的比例关系,合理规... 目的解决时变AGV小车多物流任务配送路线的平均配送时间较长的问题。方法提出一种时变AGV小车多物流任务配送路线的实时正弦余弦算法(Sine Cosine Algorithm,SCA)。通过建立车辆运输动态模型,求解配送时效性与关键参数的比例关系,合理规划AGV负载。以最短路径与最短配送时间为平衡条件构建目标函数,确定配送时间的极限范围。利用SCA优化算法的搜索与开发区间,计算随机值在不同区间的决策影响,定义同时满足最短距离与最短时间的目标函数区间,并通过迭代寻优输出最优配送路线。结果该方法在正常与拥堵路况下均能实现最优配送,随着任务数量增加,平均配送时间始终保持在25min以内,体现了良好的实时性能。结论所提出的实时SCA优化算法能有效规划时变AGV小车的配送路线,在不同路况与任务规模下均可实现配送时间短、实时性高的物流配送。 展开更多
关键词 时变AGV小车 多物流任务配送路线 sca优化算法 目标函数 配送时效性
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Study on the Planning of Cluster-based Scenic Areas with Jingyanggang Scenic Area as an Example
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作者 翟付顺 于守超 +1 位作者 张秀省 李文静 《Journal of Landscape Research》 2010年第3期9-12,共4页
Cluster-based scenic area is a special form within the scenic area system, scenic areas are always scattered with diversified landscape resources, thus planning should be made according to actual conditions of the loc... Cluster-based scenic area is a special form within the scenic area system, scenic areas are always scattered with diversified landscape resources, thus planning should be made according to actual conditions of the local area, and pertinent measures should be applied. Through elaborating the detail work in the overall planning of Jingyanggang Scenic Area, such as landscape division, spatial layout and sightseeing structure, the authors discussed several problems should be paid more attention in the planning of cluster-based scenic areas. 展开更多
关键词 cluster-based scenic areas PLANNING Jingyanggang
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Effective search with saliency-based matching and cluster-based browsing 被引量:4
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作者 张晓宇 《High Technology Letters》 EI CAS 2013年第1期105-109,共5页
Similarity matching and this paper, a saliency-based information presentation are two matching algorithm is proposed key factors in information retrieval. In for user-oriented search based on the psychological studies... Similarity matching and this paper, a saliency-based information presentation are two matching algorithm is proposed key factors in information retrieval. In for user-oriented search based on the psychological studies on human perception, and major emphasis on the saliently similar aspect of objects to be compared is placed and thus the search result is more agreeable for users. After relevant results are obtained, the cluster-based browsing algorithm is adopted for search result presentation based on social network analysis. By organizing the results in clustered lists, the user can have a general understanding of the whole collection by viewing only a small part of results and locate those of major interest rapidly. Experimental results demonstrate the advantages of the proposed algorithm over the traditional work. 展开更多
关键词 information retrieval saliency-based matching human perception cluster-based browsing social network
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Capacity Research in Cluster-Based Underwater Wireless Sensor Networks Based on Stochastic Geometry 被引量:2
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作者 Xia Li Dongxue Zhao 《China Communications》 SCIE CSCD 2017年第6期80-87,共8页
Underwater wireless sensor networks(UWSNs) have attracted wide attention in recent years.The capacity research on it is still in the initial stage,lacking adequate performance evaluation for network construction.This ... Underwater wireless sensor networks(UWSNs) have attracted wide attention in recent years.The capacity research on it is still in the initial stage,lacking adequate performance evaluation for network construction.This paper will focus on this subject by theoretical analysis and simulation,aiming to provide some insights for the actual UWSNs construction.According to the structure features of cluster-based UWSNs and the propagation characteristics of underwater acoustic signal,with the combination of signal to interference plus noise ratio,we define some capacity performance metrics,such as outage probability and transmission capacity.Based on the theory of stochastic geometry,a network capacity analytical model used in the cluster-based UWSNs is presented.The simulation results verify the validity of the theoretical analysis,and the cause of error between theoretical and simulation results has also been clearly explained. 展开更多
关键词 underwater wireless sensor networks cluster-based transmission capacity stochastic geometry
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Cluster-Based Distributed Algorithms for Very Large Linear Equations
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作者 古志民 MARTA Kwiatkowska 付引霞 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期66-70,共5页
In many applications such as computational fluid dynamics and weather prediction, as well as image processing and state of Markov chain etc., the grade of matrix n is often very large, and any serial algorithm cannot ... In many applications such as computational fluid dynamics and weather prediction, as well as image processing and state of Markov chain etc., the grade of matrix n is often very large, and any serial algorithm cannot solve the problems. A distributed cluster-based solution for very large linear equations is discussed, it includes the definitions of notations, partition of matrix, communication mechanism, and a master-slaver algorithm etc., the computing cost is O(n^3/N), the memory cost is O(n^2/N), the I/O cost is O(n^2/N), and the com- munication cost is O(Nn ), here, N is the number of computing nodes or processes. Some tests show that the solution could solve the double type of matrix under 10^6 × 10^6 effectively. 展开更多
关键词 Gaussian elimination PARTITION cluster-based distributed computing
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A Cluster-Based Random Key Revocation Protocol for Wireless Sensor Networks 被引量:1
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作者 Yi Jiang Hao-Shan Shi 《Journal of Electronic Science and Technology of China》 2008年第1期10-15,共6页
In recent years,several random key pre-distribution schemes have been proposed to bootstrap keys for encryption,but the problem of key and node revocation has received relatively little attention.In this paper,based o... In recent years,several random key pre-distribution schemes have been proposed to bootstrap keys for encryption,but the problem of key and node revocation has received relatively little attention.In this paper,based on a random key pre-distribution scheme using clustering,we present a novel random key revoca-tion protocol,which is suitable for large scale networks greatly and removes compromised information efficiently.The revocation protocol can guarantee network security by using less memory consumption and communication load,and combined by centralized and distributed revoca-tion,having virtues of timeliness and veracity for revoca-tion at the same time. 展开更多
关键词 cluster-based key pre-distribution revocation wireless sensor networks.
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CAPA-MIMO连续波束成形的SCA能效优化
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作者 李红 左加阔 +2 位作者 张登银 张兆维 鲍楠 《通信技术》 2025年第11期1162-1171,共10页
连续孔径阵列多输入多输出(CAPA-MIMO)作为6G潜在关键技术,能够在近场通信中实现高自由度波束成形。针对现有离散MIMO、迫零(ZF)及加权最小均方误差(WMMSE)方案存在能效低、计算复杂度高的问题,提出了基于连续凸逼近(SCA)的能效优化框架... 连续孔径阵列多输入多输出(CAPA-MIMO)作为6G潜在关键技术,能够在近场通信中实现高自由度波束成形。针对现有离散MIMO、迫零(ZF)及加权最小均方误差(WMMSE)方案存在能效低、计算复杂度高的问题,提出了基于连续凸逼近(SCA)的能效优化框架:首先,通过电磁场理论将连续电流模式转化为非凸优化问题;其次,采用SCA算法将该问题分解为迭代凸子问题,同时创新性地引入傅里叶级数正交基,将连续电流分布在该基下展开并截断为有限项,从而将连续函数表示转换为一组离散傅里叶级数,以便数值求解与优化。仿真结果表明,所提方案的能效较传统方案提升至少28%,在近场高频场景下增益可达40%以上,同时显著降低了计算复杂度。 展开更多
关键词 系统能效 波束成形 sca 连续孔径MIMO 能效优化
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Pre-Emptive Traffic Management for a Cluster-Based TDMA System in Vehicular Communications
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作者 Nyoman W. Prasetya Tsang-Ling Sheu +1 位作者 Achmad Basuki Muhammad Aziz Muslim 《Journal of Computer and Communications》 2017年第1期31-52,共22页
The IEEE 802.11p is a standard in a vehicular communication system, known as Wireless Access in Vehicular Environment (WAVE). An implementation of that standard as the MAC Protocol in a high-density of nodes in Vehicu... The IEEE 802.11p is a standard in a vehicular communication system, known as Wireless Access in Vehicular Environment (WAVE). An implementation of that standard as the MAC Protocol in a high-density of nodes in Vehicular Ad-Hoc Networks (VANETs) may create a performance drawback, in particular for packet loss and delay whenever collisions happen. Introducing Time Division Multiple Access (TDMA) schemes can improve the performance. However, TDMA scheduling is difficult to manage the case of high-density of traffic, the high mobility of vehicles, and dynamic network topology. This journal proposes a clustered-based TDMA by traffic priority in VANETs. The clustered traffic is defined as high and low traffic priority and embedded in TDMA MAC Header. The evaluation result obtained through NS3 Simulator shows that the proposed approach performed better in a high-density of nodes. 展开更多
关键词 VANET cluster-based TDMA MAC QOS PRIORITY
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Optimal Positions of Relay Stations for Cluster-Based Two-Hop Cellular Network
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作者 Hrishikesh VENKATARAMAN Pradeep Kumar JAIN Segu REVANTH 《International Journal of Communications, Network and System Sciences》 2009年第4期283-292,共10页
Multihop cellular networks is an exciting and a fledgling area of wireless communication which offers huge potential in terms of coverage enhancement, data-rates, power reduction, and various other quality of service ... Multihop cellular networks is an exciting and a fledgling area of wireless communication which offers huge potential in terms of coverage enhancement, data-rates, power reduction, and various other quality of service improvements. However, resource allocation in MCN is an NP-hard problem. Hence, significant research needs to be done in this field in order to efficiently design the radio network. In this paper, optimal position of relay stations in a hierarchical cluster-based two-hop cellular network is investigated. Vector algebra has been used to derive general equation for carrier-to-interference ratio (C/I) of a mobile station. It has been observed that when the transmit power of base station (BS) and the gateway (GTW)/relay station (RS) are same, the RSs should be located close to mid-point of BS and the edge of the cell. However, significantly, when the transmit power of the BS is greater than that of the GTW, then the RSs should be placed closer to the edge of the cell, in order to maximize the minimum C/I at any point in the cell. This in turn results in higher modulation technique at the physical layer, and hence, a higher data-rate to all the users in the system. 展开更多
关键词 cluster-based Design Power Control RELAY STATIONS Two-Hop CELLULAR
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Cluster-Based Design for Two-hop Cellular Networks
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作者 Hrishikesh VENKATARAMAN Sinan SINANOVIC Harald HAAS 《International Journal of Communications, Network and System Sciences》 2008年第4期370-385,共16页
Optimal resource allocation with an objective of maximizing the system capacity is an NP-hard problem in multihop cellular networks. Hence, different heuristic algorithms have been developed over the years that would ... Optimal resource allocation with an objective of maximizing the system capacity is an NP-hard problem in multihop cellular networks. Hence, different heuristic algorithms have been developed over the years that would improve the network system capacity. In this paper, a novel cluster-based architecture is proposed for a two-hop cellular network whereby the transmission distance between any communicating pair is restricted to half the cell radius. In this design, a given radio resource is used by two simultaneously communicating pairs in every hexagonal cell, but for only half the time slot period. The characteristic feature of this cluster-based design is that it enables a frequency reuse ratio of one. The proposed hierarchical system is analyzed and tested under realistic propagation conditions including lognormal shadowing. It has been observed that the system capacity of a cluster-based design is 2.5 times that obtained from the single-hop cellular system with no relaying. In addition, the cluster-based design achieves higher capacity compared to state-of-the-art two-hop algorithms. This is an important finding since the hierarchical cluster-based approach has fewer degrees of freedom in the selection of the routing path for the end-to-end connection. Practical routing algorithms should be able to benefit from this. 展开更多
关键词 cluster-based Design Synchronized RESOURCE REUSE INTERFERENCE Model SPATIAL PROTECTION MARGIN
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Strengthening the Competitiveness of SMEs by Using the Cluster-Based Approach: A Case Study of the Ratchaburi Orchid Cluster in Thailand
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作者 Boon-Anan Phinaitrup 《Journal of Modern Accounting and Auditing》 2012年第2期195-206,共12页
This paper studies the application of the cluster-based approach in the enhancement of the competitiveness of Thailand's SME industry. The author had employed a qualitative method through the in-depth interview. The ... This paper studies the application of the cluster-based approach in the enhancement of the competitiveness of Thailand's SME industry. The author had employed a qualitative method through the in-depth interview. The result showed that Ratchaburi orchid cluster in Thailand has employed the concept of the cluster-based approach since they realized that it was useful and could enable them to produce good quality orchids for the international market. The finding also showed how individuals have worked together and helped each other, in order to build a good horizontal network of support and creating competitive advantages. In addition, the research paper related to knowledge management because knowledge management refers to a method for development which requires cluster members to exchange information, interact with each other, sharing and distribute information, create closer business relationship and build mutual benefit. Therefore, the cluster members will help each other to create a culture that values learning through making a commitment and sharing information to strengthen the cluster. 展开更多
关键词 cluster-based approach SME competitive advantage Thailand
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基于SCA的多模式接口适配模块设计
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作者 王少飞 郭强 张磊 《通信电源技术》 2025年第18期41-43,74,共4页
对于多通道软件无线电设备,解决设备内部网络与外部不安全网络间的多路并行数据高速传输问题是一项设计难点。基于此,提出一种基于软件无线电软件通信体系架构(Software Communication Architecture,SCA)硬件抽象层标准的多模式、高速... 对于多通道软件无线电设备,解决设备内部网络与外部不安全网络间的多路并行数据高速传输问题是一项设计难点。基于此,提出一种基于软件无线电软件通信体系架构(Software Communication Architecture,SCA)硬件抽象层标准的多模式、高速率接口适配模块设计方法,通过多通道的虚拟化接口设计,实现多波形业务数据并行数据流的复接与分发。经过平台验证,本设计支持总吞吐量不低于12 Gb/s的多路并行业务数据传输,可满足多通道、多模式下软件无线电波形的并行数据复接与分发需求。 展开更多
关键词 软件通信体系架构(sca) 软件无线电 硬件抽象层
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Establishment of a humanized SCA2 mouse model carrying a CAA disruption preventing CAG repeat expansion in pathogenic genes
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作者 Yao Zhang Yufei Li +7 位作者 Lin Zhang Zhaoqing Li Keqin Lin Kai Huang Zhaoqing Yang Shaohui Ma Hao Sun Xiaochao Zhang 《Animal Models and Experimental Medicine》 2025年第9期1677-1687,共11页
Background:Spinocerebellar ataxia type 2(SCA2)is a neurodegenerative disease marked by significant clinical and genetic heterogeneity,primarily caused by expanded CAG mutations in the ATXN2 gene.The unstable expansion... Background:Spinocerebellar ataxia type 2(SCA2)is a neurodegenerative disease marked by significant clinical and genetic heterogeneity,primarily caused by expanded CAG mutations in the ATXN2 gene.The unstable expansion of CAG repeats disrupts the genetic stability of animal models,which is detrimental to disease research.Methods:In this study,we established a mouse model in which CAG repeats do not undergo microsatellite instability(MSI)across generations.A humanized ATXN2 cDNA with four CAA interruptions within 73 CAG expansions was inserted into the Rosa26 locus of C57BL/6J mice.A 23 CAG control mouse model was also generated to verify ATXN2 integration and expression.Results:In our model,the number of CAG repeats remained stable during transmission,with no CAG repeat expansion observed in 64 parent-to-offspring transmissions.Compared with SCA2-Q23 mice,SCA2-Q73 mice exhibited progressive motor impairment,reduced Purkinje cell count and volume(indicative of cell atrophy),and muscle atrophy.These observations in the mice suggest that the behavioral and neuropathological phenotypes may reflect the features of SCA2 patients.RNA-seq analysis of the gastrocnemius muscle in SCA2-Q73 mice showed significant changes in muscle differentiation and development gene expression at 56 weeks,with no significant differences at 16 weeks compared to SCA2-Q23 mice.The expression level of the Myf6 gene significantly changed in the muscles of aged mice.Conclusion:In summary,the establishment of this model not only provides a stable animal model for studying CAG transmission in SCA2 but also indicates that the lack of long-term neural stimulation leads to muscle atrophy. 展开更多
关键词 ATXN2 CAA interruption genetic stability mouse model sca2
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基于SCA-PSO的支持向量回归车辆尾气传感器温湿度补偿方法研究
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作者 吕应明 袁文平 《电子技术应用》 2025年第5期38-43,共6页
氮氧化物和颗粒物是柴油机车尾气排放的两种主要污染物。利用车辆尾气检测装置对柴油机车进行尾气排放监控是治理城市空气污染的一项有效措施。对于氮氧化物气体传感器而言,基于其检测原理,温度和湿度会对其检测过程发生的化学反应产生... 氮氧化物和颗粒物是柴油机车尾气排放的两种主要污染物。利用车辆尾气检测装置对柴油机车进行尾气排放监控是治理城市空气污染的一项有效措施。对于氮氧化物气体传感器而言,基于其检测原理,温度和湿度会对其检测过程发生的化学反应产生较大影响,因此需要相应的温湿度补偿方法来提升传感器测量精度。为此,设计了一种车载式车辆尾气检测装置,并提出了一种基于正余弦优化算法(SCA)和改进式粒子群优化算法(PSO)的支持向量回归(SVR)的传感器温湿度补偿方法,通过传感器实时检测氮氧化物气体和颗粒物浓度,并利用补偿模型对传感器检测值进行温湿度补偿。经过测试数据训练和验证,补偿模型可以有效降低由温湿度造成的误差,能够满足工程需求。 展开更多
关键词 尾气检测 物联网 支持向量机 正余弦优化 粒子群优化 温湿度补偿
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基于分布式SCA应用的CORBA性能分析 被引量:4
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作者 廖文瑜 刘文斌 +1 位作者 苏旸 丛键 《中国电子科学研究院学报》 2011年第5期524-528,共5页
介绍了基于软件通信体系结构(SCA)的波形与CORBA的关系,阐明了CORBA对系统传输的重要性,测试了CORBA性能在多处理器分布式软件无线电的硬件开发平台下的性能,给出了测试结果,分析了影响ORB性能的因素,最后总结了当前解决分布式多处理器... 介绍了基于软件通信体系结构(SCA)的波形与CORBA的关系,阐明了CORBA对系统传输的重要性,测试了CORBA性能在多处理器分布式软件无线电的硬件开发平台下的性能,给出了测试结果,分析了影响ORB性能的因素,最后总结了当前解决分布式多处理器平台高速数据传输与交互的方法。 展开更多
关键词 多处理器波形开发 sca CORBA 性能测试
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SCA中CORBA与硬件抽象层技术研究 被引量:7
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作者 崔晓鹏 胡中豫 张豪 《现代电子技术》 2011年第6期32-35,共4页
为了彻底分清SCA中两个容易混淆的关键技术,即CORBA和硬件抽象层技术,采用比较研究的方法,将两者从基本定义、体系结构、应用和实现方法等几个方面进行了深入研究,得出了CORBA和硬件抽象层在一定的应用范围内均可被认为是一种中间件技术... 为了彻底分清SCA中两个容易混淆的关键技术,即CORBA和硬件抽象层技术,采用比较研究的方法,将两者从基本定义、体系结构、应用和实现方法等几个方面进行了深入研究,得出了CORBA和硬件抽象层在一定的应用范围内均可被认为是一种中间件技术;CORBA属于SCA软件架构的一部分,而硬件抽象层则归属为SCA的硬件结构部分;硬件抽象层组件是不能被CORBA直接调用的功能组件等结论,两者都具有屏蔽各种平台间的差异和编程语言不同的特点。 展开更多
关键词 sca CORBA 硬件抽象层 中间件
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基于控制论的SCA武器系统效能评估方法 被引量:13
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作者 杨峰 李群 +3 位作者 孔德培 王维平 朱一凡 沙基昌 《系统工程与电子技术》 EI CSCD 北大核心 2002年第12期56-58,64,共4页
分析了现代武器系统所面临的两大挑战———体系复杂性挑战和不确定性挑战。指出武器系统作战效能不仅取决于自身的作战潜能 ,而且受己方探测系统与指控系统效能的约束 ,并且反映在由防御方的探测系统、指控系统与武器系统组成的敌对战... 分析了现代武器系统所面临的两大挑战———体系复杂性挑战和不确定性挑战。指出武器系统作战效能不仅取决于自身的作战潜能 ,而且受己方探测系统与指控系统效能的约束 ,并且反映在由防御方的探测系统、指控系统与武器系统组成的敌对战场力量体系的对抗效能上。在此基础上 ,阐述了现有武器系统作战效能评估方法的不足 ,提出了一种基于控制论思想的武器系统作战效能评估方法———SCA ,运用关系代数给出了其模型算法 ,并提供了一个具体的评估实例。 展开更多
关键词 控制论 sca 武器系统 效能评估 关系代数 模型
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基于SCA软件无线电硬件平台的设计 被引量:3
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作者 赵秋明 沈博 胡晓鹏 《电视技术》 北大核心 2011年第19期48-50,共3页
介绍了一种基于SCA软件无线电硬件平台的具体设计方案,通过对平台的资源需求估计,确定以DSP+FPGA为核心器件构建一套具有高度灵活性和开放性的通用通信平台,该平台能够完成信号的基带和中频处理,从而实现多模式、多频段、多信道等通信... 介绍了一种基于SCA软件无线电硬件平台的具体设计方案,通过对平台的资源需求估计,确定以DSP+FPGA为核心器件构建一套具有高度灵活性和开放性的通用通信平台,该平台能够完成信号的基带和中频处理,从而实现多模式、多频段、多信道等通信功能。 展开更多
关键词 数字信号处理 现场可编程门阵列 sca 软件无线电 通信
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一种支持动态管理的SCA服务模型研究 被引量:2
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作者 龙军 赵贵虎 张祖平 《计算机科学》 CSCD 北大核心 2012年第12期114-117,共4页
为解决SCA和OSGi的结合在分布式环境下不能很好支持运行时组件模型动态管理的问题,在分析二者传统结合方式的基础上,建立了一种基于OSGi的SCA服务模型——DOSGi_SCA。DOSGi_SCA以分布式OSGi为基础,构建了服务注册中心来管理本地服务和... 为解决SCA和OSGi的结合在分布式环境下不能很好支持运行时组件模型动态管理的问题,在分析二者传统结合方式的基础上,建立了一种基于OSGi的SCA服务模型——DOSGi_SCA。DOSGi_SCA以分布式OSGi为基础,构建了服务注册中心来管理本地服务和远程服务,实现了在分布式环境下支持运行时组件模型的动态管理。应用实例表明,该模型实现了SCA和OSGi的优势互补,充分发挥了各自的优点,弥补了各自的不足。 展开更多
关键词 sca 动态管理 组件模型 分布式OSGi DOSGi_sca
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SCA无线寻呼发射与接收 被引量:1
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作者 吴建辉 时龙兴 孙大有 《应用科学学报》 CAS CSCD 2000年第4期317-321,共5页
分析了SCA无线寻呼的发射机理,探讨了SCA无线寻呼的接收方法,重点提出了一种新的拓扑结构来单片实现SCA的射频接收,并以MATLAB进行仿真论证.
关键词 sca无线寻呼 零中频 sca发射 sca接收
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