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41.
按不同设防烈度设计10层框架-剪力墙结构,计算了不同设防烈度下的建筑工程造价。对比可知,设防烈度8度以下,设防水准提高一个等级,建筑工程造价增加比例小于6.97%,增加成本占房屋售价的比例小于0.852%。框架-剪力墙结构建筑工程造价较小的增加,可获得设防水准一个等级的提高。从另一个角度说,在减少建筑面积很小的情况下,房屋的抗震设防水准可获得一个等级的提高。  相似文献   
42.
介绍了一种基于PXIe总线多通道数字化仪模块的总体设计方案.该数字化仪模块采用四片250MSa/s、16位ADC与FPGA做为数据采集控制与信号处理核心单元,实现四个通道并行数据采集存储功能.模块采用PXIe总线接口,利用DMA模式实现主控单元与采集单元的高速数据传输,开发了基于QT的软面板及驱动程序,既保证了模块跨平...  相似文献   
43.
利用酒精废醪培养假丝酵母作单细胞蛋白,对提高假丝酵母的蛋白质含量和含硫的氨基酸含量的半定向选育方法进行了摸索,使目的变异株的蛋白质含量平均提高了14%,其中一个变异株在蛋白质含量提高的同时,蛋氨酸含量提高了约40%  相似文献   
44.
本文提出了一种经过改进的瞬态信号参数化方法并讨论了这种方法在核爆炸探测领城内的应用。重点阐述了信号建模及参数提取的计算方法,最后给出了本方法在核爆炸识别中的典型实例及计算机仿真结果。  相似文献   
45.
Comparing to the traditional multihop ad hoc networks, dynamic spectrum environment is the special characteristic of CRAHN (cognitive radio ad hoc networks). Therefore, the cognitive users will show their selfishness on spectrum bandwidth cost in multihop communication. In CRAHN, multipath routing is a reasonable choice when considering efficiency and stability. In order to take further advantage of efficiency of multipath routing, this paper study the efficiency-awareness traffic assignment problem of multipath routing in CRAHN. There are several existing game based traffic assignment schemes for selfish wireless network, however, all of them can not be directly applicable to CRAHN. In addition, none of the existing works studied whether the scheme is efficient. In this paper, a noncooperative differential game is proposed, and the equilibrium of the game is computed and proved to be an efficient traffic assignment for multipath routing in CRAHN. Besides this, we also optimize the total cost of game from the game designer’s point of view, and give a simple example to illustrate the optimization procedure.  相似文献   
46.
Knowledge graph is a useful resources and tools for describing entities and relationships in natural language processing tasks.However,the existing knowledge graph are incomplete.Therefore,knowledge graph completion technology has become a research hotspot in the field of artificial intelligence,but the traditional knowledge graph embedding method does not fully take into account the role of logic rules and the effect of false negative samples on knowledge embedding.Based on the logic rules of knowledge and the role of adversarial learning in knowledge embedding,we proposes a model to improve the completion of knowledge graph:soft Rules and graph adversarial learning (RUGA).Firstly,the traditional knowledge graph embedding model is trained as generator and discriminator by using adversarial learning method,and high-quality negative samples are obtained.Then these negative samples and the existing positive samples together constitute the label triple in the injection rule model.The whole model will benefit from both high-quality samples and logical rules.In addition,we evaluated the performance of link prediction task and triple classification task on Freebase and Yago datasets respectively.Finally,the experimental results show that the model can effectively improve the effect of knowledge graph completion.  相似文献   
47.
防空兵指挥控制网络可视化问题研究   总被引:1,自引:0,他引:1  
文中在传统防空作战防空兵指挥控制网络的基础上,运用WS小世界网络模型理论构建了网络化防空作战防空兵指挥控制模型。使用Matlab语言对模型进行了仿真,并且使用了稀疏矩阵的方法,解决了大型网络仿真分析消耗内存巨大、难以进行仿真的问题。对网络化防空作战的组织和实施有一定的参考价值。  相似文献   
48.
在大型科学计算过程中往往会出现海量中间数据,需要在不同开发平台或语言之间传递,此时中间数据会消耗大量系统资源,引起系统性能急剧下降;此外,中间数据长度的不确定性和跨平台的移植性都对科学计算算法提出了较高的接口要求;为保证系统的稳定性和可移植性,文中提出一种基于随机文件读写进行数据传递的简单实用方法,来实现在C#.NET平台下的托管代码中调用C语言开发的非托管代码的交互模式。  相似文献   
49.
GaN buffer layers (thickness ~60nm) grown on GaAs(001) by low-temperature MOCVD are investigated by X-ray diffraction pole figure measurements using synchrotron radiation in order to understand the heteroepitaxial growth features of GaN on GaAs(001) substrates.In addition to the epitaxially aligned crystallites,their corresponding twins of the first and the second order are found in the Xray diffraction pole figures.Moreover,{111} φ scans with χ at 55°reveal the abnormal distribution of Bragg diffractions.The extra intensity maxima in the pole figures shows that the process of twinning plays a dominating role during the growth process.It is suggested that the polarity of {111} facets emerged on (001) surface will affect the growth twin nucleation at the initial stages of GaN growth on GaAs(001) substrates.It is proposed that twinning is prone to occurring on {111}B,Nterminated facets.  相似文献   
50.
In this paper, a media access control (MAC) protocol is proposed for multimedia traffic in slotted CDMA wireless communication systems. The channel resource is partitioned into four compartments: video, voice and data compartments, and common resource pool (CRP) which can be used by either voice or data. Video is only permitted to use its pre-allocated channels. Besides assigning voice to its own compartment, a threshold type decision policy is introduced to regulate voice call admission control in CRP. Data can use not only data and CRP compartments, but also the idle capacity of both video and voice. The proposed protocol provides a simple and flexible resource allocation decision for the multimedia traffic such that the bandwidth can be utilized efficiently while satisfying the quality of service (QoS) requirement for each traffic category. Two mathematical analysis methods are applied to evaluate the system performance. The first, Traditional Markov Analysis (TMA) is used to calculate the video and the voice blocking probabilities, and the second, Transient Fluid Analysis (TFA) is adopted to evaluate the average data delay and the channel utilization. Computer simulations verify the accuracy of mathematical models.Miao Ma received the B.Eng. and M.Eng. degrees in Electrical Engineering from Harbin Institute of Technology, China in 1992 and 1996, respectively, and the Ph.D degree in Electrical and Electronic Engineering from Nanyang Technological University, Singapore in 2003. She is a research scientist in the Institute for Infocomm Research in Singapore. Her research interests include network security, media access control, wireless communications and computer networking.Erry Gunawan received the B.Sc. degree in electrical and electronic engineering from the University of Leeds, U.K., in 1983 and the M.B.A. and the Ph.D. degrees, both from Bradford University, in 1984 and 1988, respectively. From 1984 to 1988, he was a Satellite Communication System Engineer at Communication Systems Research Ltd., Ilkley, U.K. In 1988, he moved to Space Communication (SAT-TEL) Ltd, Northampton, U.K. He joined the School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, in 1989, and currently, he is an Associate Professor in the same school. His research interests include the fields of digital communications, mobile and satellite communications, error coding, and spread spectrum. He has published over 60 international research papers and has been a consultant to a local company on the study of DECT system and BLUETOOTH.  相似文献   
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