共查询到20条相似文献，搜索用时 39 毫秒
1.
为了改进网络存储设备的I/O速度和系统性能, 设计了一种新的专用存储服务器, 该服务器是一种基于iSCSI的附网存储服务器 (iSCSI-based network-attached storage server, iNAS). 在iNAS中, 利用iSCSI软件提供的模块, 使得iNAS同时提供file I/O 和block I/O服务, 实现了NAS和SAN (storage area network)的融合; 通过在RAID (redundant array of inexpensive disks)控制器和用户内存之间的直接数据传输(零拷贝), 极大地提高了iNAS的I/O响应速度; 通过一个多级分流的的设备驱动程序, 将多个RAID整合成单一的存储池, 从而实现了存储虚拟化. 实验结果显示, iNAS对文件I/O请求和块I/O请求都具有极高的响应速度. 相似文献
2.
存储网络是个大而复杂且昂贵的网络,使用传统的SCSI技术成本虽低,但传输数据时会受距离及路径的限制,先进的FC技术消除了这些弊端,提高了传输速率,但其结构复杂,投资大,管理难.用户期待更简单、成本低、能够充分利用已有以太网环境完成数据存储的工作,于是iSCSI技术应运而生.本文对iSCSI协议的工作原理、应用及特点等进行了论述. 相似文献
3.
Study on performance of a packed bed latent heat thermal energy storage unit integrated with solar water heating system 总被引：1，自引：0，他引：1
NALLUSAMY N. SAMPATH S. VELRAJ R. 《浙江大学学报(A卷英文版)》2006,7(8):1422-1430
INTRODUCTION Efforts of rational and effective energy man-agement, as well as environmental considerations, increase the interest in using renewable energy sources, especially solar energy. Because of discrep-ancy between the energy supply and demand in solar heating applications, a thermal energy storage (TES) device has to be used for the most effective utilization of the energy source. Energy storage combined with solar collectors and photovoltaic systems have been developed over the… 相似文献
4.
我国高等教育大众化政策的反思与展望 总被引：2，自引：0，他引：2
从政策分析的角度看,目前我国高等教育大众化政策还存在决策机制不健全、片面追求量的指标、路径单一等谤多问题。创新与健全高等教育大众化政策需要加强政策研究,健全科学决策机制;积、极发展民办高校,实现大众教育与精英教育的协调发展;贯彻科学发展观,追求量与质的和谐统一。 相似文献
5.
With development of networked storage and its applications, united storage network (USN) combined with network attached storage (NAS) and storage area network (SAN) has emerged. It has such advantages as high performance, low cost, good connectivity, etc. However the security issue has been complicated because USN responds to block I/O and file I/O requests simultaneously. In this paper, a security system module is developed to prevent many types of atl~cks against USN based on NAS head.The module not only uses effective authentication to prevent unauthorized access to the system data, but also checks the data integrity.Experimental results show that the security module can not only resist remote attacks and attacks from those who has physical access to the USN, but can also be seamlessly integrated into underlying file systems, with little influence on their performance. 相似文献
6.
潘旭 《闽西职业技术学院学报》2014,(3):115-120
从现有各种网络存储技术的基本原理出发,分析了每一种网络存储技术的优点和存在的问题,围绕目前的几种主流网络存储技术进行了讨论。结合大数据的基本概念进行剖析,并对大数据的主要应用和网络存储作简单对比。最后归纳总结大数据时代所面临数据存储的新挑战。 相似文献
7.
The article argues that there is no single globalisation of education systems, but rather multiple globalisations of each system taken in its individual context. We propose three explanatory factors to account for these vernacular globalisation processes, that is, for individual policy trajectories in each national context: path dependence on earlier policy choices and institutions, education policy-making through bricolage, and finally the translation by national actors of international-level ideas or tools as a function of the debate, institutions or national power dynamics in question. The research design is based on the study of a most-likely case: accountability policy in two school systems – France and Quebec – which show strong variations. Document analyses and semi-structured interviews were conducted in both cases. In the two countries, distinct vernacular globalisations are at work leading to different neo-statist accountability policies. In Quebec, the reinforcement of state power through a growing vertical accountability and the systematic development of regulation tools between policy actors and levels lead to a ‘centralisation by institutional linkage’. In France, we rather witness a ‘globalisation by discursive internalisation’ in which transnational imperatives are integrated in official discourses on the regulation of the education system, but without radically questioning the mainstays of this regulation. 相似文献
8.
政策评估、反思与重构是我国教育政策运行的一般性路径抉择.在对政策评估、反思与重构等相关要素分析的基础上,通过对我国高职院校评估政策更替的历史回顾提出,评估政策目标的转向必然导致对原政策"四大情结"的反思.从深度访谈、评估结论、数据平台等方面进行政策重构的解读后发现,针对旧方案存在的"四大情结"取向,新方案一方面删除了部分过时、无效的指标,改变了过去那种以查证、审核、抽检为主要任务的专家组做法;另一方面开发并形成了以数据采集平台为主要手段的评估体系,并采用了深度访谈的专家评估方式.评估政策的重构将引领新一轮高职评估的开展. 相似文献
9.
针对现有单一运营商提供的云存储方案,无法令用户跨运营商定制组建个人的云存储服务的缺陷,设计了一种模块化的存储方案.该方案涵盖了用户数据的传输安全、存储安全以及访问控制安全,并确保数据的机密性、可用性和完整性.该方案适用于云服务运营商面向用户提供高安全的网络存储服务,有利于用户在不同运营商之间迁移存储数据. 相似文献
10.
多路视频存储与检索容易造成I/O瓶颈,以及多用户回放的稳态性和连续性较差等问题,易导致整个监控系统的效率低下与不稳定性.基于组件化思想提出一种嵌入式Linux数字视频监控系统多维硬盘存储调度方案,有效地解决I/O瓶颈问题,提高了存储高效快捷性.同时通过采用η-dispatching方案提高网络数字视频监控系统的多路视频存储与并发用户检索的效率与模块化的通用性. 相似文献
11.
An underground heat storage system in a double-film-covered greenhouse and an adjacent greenhouse without the heat storage system were designed on the basis of plant physiology to reduce the energy consumption in greenhouses. The results indicated that the floor temperature was respectively 5.2℃, 4.6℃ and 2.0 ℃ higher than that of the soil in the adjacent reference greenhouse after heat storage in a clear, cloudy and overcast sky in winter. Results showed that the temperature and humidity were feasible for plant growth in the heat saving greenhouse. 相似文献
12.
A two-stage method is developed to solve a new class of multi-storage tank multi-source （MTMS） systems. In the first stage, the optimal storage policy of each tank is determined according to the electricity tariff, and the ground-level storage tank is modeled as a node. In the second stage, the genetic algorithm, combined with a repairing scheme, is applied to solve the pump scheduling problem. The objective of the pump scheduling problem is to ensure that the required volume is adequately provided by the pumps while minimizing the operation cost （energy cost and treatment cost）. The decision variables are the settings of the pumps and speed ratio of variable-speed pumps at time steps of the total operational time horizon. A mixed coding methodology is developed according to the characteristics of the decision variables. Daily operation cost savings of approximately 11% are obtained by application of the proposed method to a pressure zone of S. Y. water distribution system （WDS）, China. 相似文献
13.
田平 《十堰职业技术学院学报》2008,21(5):4-6
对于我国的基本国策,人们在理解和执行中存在着一些问题。主要是容易产生理解偏差,使用随意性大,认同度和重视程度不同,实际工作中的执行力强弱不同等问题。因此,对基本国策要以科学辩证的思维方法去理解,明确基本国策的标准,强化权威性,提高执行力,以保证其对国民经济和社会发展的重要指导作用。 相似文献
14.
周珂 《北京城市学院学报》2014,(1):23-29
国策机制从根本上来说是行政主导的环境资源保护路径,它有自己的优势,特别是在特定时期的优势,但也存在局限性。国策机制对公众具有神秘性和对立性。西方的社会生态运动最早得到的是社会认可,其次得到了法律的认可,成为环境立法、司法和行政的源泉。社会生态运动初期的效率可能是较低的,而一旦它被公众所认可,会形成全社会的自觉行动;国策机制在初期其效率远高于社会生态运动,但是它在公众中的影响力是有限的,甚至会造成公众对环境问题的冷漠。中国的环境资源保护要突破固有的行政主导的局限,需实现从国策上升到法律的转变,需要加强社会生态运动的理论和制度建设,并注重国际交流和与本国国情适应的经验借鉴,逐渐使社会生态运动在中国实现其对司法、立法和行政的影响。 相似文献
15.
李晓燕 《安阳师范学院学报》2006,(1):12-13
政策修正和废止下的评价;政策的后续性评价及其一些指导原则;多重利益相关者的参与;环境变化中的政策目标的多元化;效率和政治价值的兼顾以及政策评价中的透明;政策评价的效率和价值分析法。 相似文献
16.
介绍了基于单片机的波形采集、存储与回放系统的设计思想和实现过程,对系统实现过程中的采样频率选取、滤波电路设计、输入输出电路设计、接口电路设计和软件设计等问题进行了讨论。 相似文献
17.
通过一项农村地方教育政策的分析,指出教育政策价值选择应该以功利主义伦理原则为基础,进而得出价值选择的原则应以公正无偏原则和分配普遍原则为标准,最终以农村地方教育政策制订的适宜的方法为归宿,保障农村教育政策达到应有的效果。 相似文献
18.
介绍了一种以TI公司的TMS320LF2407A DSP芯片为核心的实时数据采集存储系统设计方案.该系统通过外接12位AD转换器AD7858来提高DSP采样精度,实时采集病人的心电数据,通过数字滤波处理后可以真实反映病人的心脏健康状况,借助串口电路建立与上位机的通讯.相对于采用PC机和单片机设计的系统,该系统具有功耗小、成本低、实时性强等优点. 相似文献
19.
中国少数民族教育政策与美国多元文化教育政策的比较分析 总被引：1，自引：0，他引：1
中国少数民族教育政策与美国多元文化教育政策有相通之处,但也有重大的差异：在政策背景与路径上相似的差异现实与不同的应对机制,政策内容与范畴上特殊优惠的同与异,政策理念上追求集体平等理念的不同理路以及政策取向上促进民族发展与追求文化承认的分野。二者保护弱者和多元一体格局的原则值得坚持,美国多元文化教育政策的制定对我国少数民族教育政策有可取之处,但我国必须对美国多元文化教育政策进行本土化的研究。 相似文献
20.
CHERALATHAN M VELRAJ R. RENGANARAYANAN S. 《浙江大学学报(A卷英文版)》2006,7(11):1886-1895
INTRODUCTION Cool thermal energy storage (CTES) using the latent heat concept as an alternative to sensible heat storage offers a good option because of its high storage density and the nearly constant temperature heat removal characteristics during the discharging cycle. Since the principle of latent cool storage nec- essarily involves a change of state, heat transfer must occur in different modes depending on the state of charging and discharging. During the periods of low cooling dema… 相似文献