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91.
针对目前风力发电机仿真仅限于某个功能或单元的建模及分析,难以进行整机控制系统仿真的问题,以双馈发电机为对象,设计与实现了风力发电机半实物仿真实验平台.该平台包括控制系统、风力机虚拟对象、通讯接口以及监控界面组成,软件之间通过自动化设备规范(ADS)协议进行数据交互融合,为整机及控制系统的性能在线评估提供支持.最后在所开发实验平台上进行了低风速仿真实验,验证了所设计平台的有效性和合理性,为风电场后期的参数评估及性能优化提供一个完善可行的实用化平台. 相似文献
92.
射频识别技术在资产管理领域中逐渐受到青睐,针对现有识别技术开发周期长、测试速度慢的弊端,论文提出采用虚拟仪器和数字信号处理技术,结合自定义超高频协议,研究了一种新的读写器系统。该系统用软件代替硬件实现超高频射频识别,能对超高频RFID标签自动测试,能够实现电子标签从物理层到应用层的一致性测试,能对多种宏观参数测量和分析。实验结果表明,该系统在单标签及多标签的情况下能克服单一标准的限制,很好地模拟读写器调制、解调、编码、解码、循环冗余校验、逻辑控制等基本功能,具有成本低、集成度高和扩展性好等优势。 相似文献
93.
李文棣 《网络安全技术与应用》2013,(11):135-136
信息总量、网络浏览人数以及人们对网络享受需求的增加,促使着信息制作水平的提高,制作水平的提高在给人们带来了更好的视觉和听觉享受的同时,也对计算机的硬件系统提出了巨大的考验.计算机内存作为计算机硬件系统的重要组成部分,能否对内存做好合理的划分,对计算机的体验具有重要的意义. 相似文献
94.
Abstract This article reports findings of a study of how leaders of virtual information systems development teams improve team trust and cooperation by managing adaptation of information and communications tools. Results indicate how Theory X (command and control) and Theory Y (facilitate and support) styles of leadership enable and hinder effective outcomes. 相似文献
95.
《国际互联网参考资料服务季刊》2013,18(4):27-34
ABSTRACT Each year Dacus Library teaches library use to over a thousand freshmen in introductory Writing classes. In the summer of 2000, two reference librarians undertook a revision of the basic methodology of teaching library use to freshmen. This change was necessitated by staff shortages, coupled with increasing enrollment. The resulting virtual tour, which was introduced in fall 2000, combined an existing audio-tape tour with one hour of classroom instruction. The university's mascot, an eagle, was used to lead the students on a tour of all three floors of Dacus Library, with explanations of each location pictured. In addition, the eagle was used to describe and explain the online catalog. The new virtual tour, while still a work in progress, is considered to be a success by students, library faculty and staff, and Writing instruction faculty. You can visit the Dacus Library tour at www.winthrop.edu/dacus/About/Tapetour/Exercises/assignment2.htm. 相似文献
96.
Jennie E. Callas 《国际互联网参考资料服务季刊》2013,18(1-2):77-78
SUMMARY Distance learning students may not think of the “campus” library as the first place to fulfill their information needs and may not even be aware of the services available to them. One way to reach these students is to adopt and adapt marketing techniques from the business world. This article examines the findings of a survey conducted at Emporia State University concerning the awareness of distance learning services. It will also examine marketing techniques and illustrate how they can be applied to increase awareness of reference support services for distance learners. 相似文献
97.
《国际互联网参考资料服务季刊》2013,18(1-2):189-208
SUMMARY University students-whether adult, distance learner, or traditional age-need access to university services and quick accurate answers to their questions beyond traditional “business” hours. Students' busy schedules and changing life patterns dictate that university services meet their needs. At DePaul University in Chicago, student focus groups repeatedly pointed to the need for one central place to get an answer or solve a problem. DePaul Central was created as an information and referral service to satisfy that student need, at the same capitalizing on the value of the librarian skill set. 相似文献
98.
Web-scale discovery systems, such as Serial Solutions’ Summon? Service, are replacing older federated search technologies as the tool for users to access library resources quickly and easily. The impact of Web-scale discovery systems on instruction is not known. This study of instruction librarian perceptions of Summon's impact on instruction and student information literacy skills is based on a survey. The survey reveals librarians’ ambivalence toward Summon. While some librarians agree that Summon has the potential to change the way librarians teach information literacy skills, it has not been fully integrated into the classroom. 相似文献
99.
The experience of the Mississippi State University (MSU) Libraries illustrates the challenges presented by moving from consortial to local chat, as well as an evaluation of the advantages of chat reference in an academic setting. Countering the consortial, instant-messaging model prevalent in virtual reference today, the MSU Libraries have found chat offers advantages in an academic community. Moving to a local setting, it was possible for the MSU Libraries to maintain quality control over chat transactions while building relationships with faculty and students across campus. 相似文献
100.
《国际互联网参考资料服务季刊》2013,18(4):29-39
ABSTRACT Designing a successful library Web site for an engineering audience means researching how engineers find and use information. It also requires the special librarian to conduct usability tests to determine what is and isn't working on the site. The special librarian is more than simply a librarian, he or she must be able to take the research and the test results and either build the Web site or make sure the site is built by a team. The librarian must be able to play several roles: researcher, tester, project leader, and Web manager. The more successful the librarian is at involving users in site design, the more used and usable the site will be. This article describes one librarian's experience with designing a special library Intranet. It also includes an extensive bibliography of related articles. 相似文献