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陈孙艺  梁小龙  李亮冰 《工业炉》2003,25(4):34-37,40
介绍了乙烯裂解炉对流段的结构功能,各部件局部结构的改善设计。  相似文献   
3.
联合循环余热锅炉螺旋鳍片管烟气放热系数研究   总被引:1,自引:0,他引:1  
东南大学建造了1座IGCC余热锅炉鳍片管受热面流动和传热热态试验装置,并先后在其上进行了2个不同螺旋鳍片管组的传热特性研究,通过分析比较实测的烟气侧对流放热系数与无量纲准则式计算的结果,得出了完全热模拟公式更为准确的结论。  相似文献   
4.
论述了一个网络化,信息化实验系统开发的方法和思路。该系统以虚拟技术为支撑,以图学教育的宗旨为核心,综合利用了虚拟技术的各种开发工具和理论,具有虚拟现实系统常有的特点,沉浸感,交互性,构想。  相似文献   
5.
蒸发式冷凝器管束中强制对流空气CFD模拟   总被引:1,自引:0,他引:1  
运用FLUENT软件对圆管、椭圆管及交变曲面波纹管管束中强制对流空气热力过程进行了模拟,模拟数据经过Tecplot.10处理后直观地表征了3种管型管束中空气的速度场、压力场及温度场。结果表明,交变曲面波纹管在提高流体湍动程度及强化传热温差方面优于其它两种管型。  相似文献   
6.
The teaching of literature through CAI raises problems of both a linguistic and instructional nature; student involvement and creativity in studying literature, and especially poetry, is difficult to build into a computer-based lesson. We have confronted these difficulties in the lessonPoetry I, which introduces undergraduates to basic concepts of poetic verse in a design using screen display, speech synthesis, and verse processing to maximize interactivity and student involvement.The lesson contains instructional modules which include the student's composition of a limerick. Computational processing of the limerick's text enables the program to offer guidance as the student composes and revises the verse and gains first-hand experience with metrical language. The significant problems inherent in processing verse are addressed by adapting Digital Equipment Corporation's DECTalk speech synthesizer as an engine converting natural language verse text into accessible strings of phonemic symbols. Although the verse processor cannot scan verse, it can interpret DECTalk's symbols reliably enough to successfully stimulate students' thinking about their verse compositions.Preliminary responses to the program have been favorable and demonstrate its effectiveness in involving students more deeply in learning about poetic verse. This suggests that the techniques of verse processing prototyped inPoetry I might be usefully extended to other types of verse and levels of study.W. Webster Newbold is an Assistant Professor of English at Ball State University, Muncie, Indiana, USA, who has recently served as English Department Computer Coordinator. His research interests include computer-assisted instruction and computer-based composition.Herbert F. W Stahlke is a Professor of English, specializing in linguistics, and currently serves as Associate Director for Academic Computing, Ball State University Computing Services. His research interests include computer-assisted instruction, natural language processing, and lexical databases.  相似文献   
7.
Technology-assisted instruction has potential for helping students improve their reading skills. In the current studies, PowerPoint software was used to supplement teacher-led reading instruction for elementary-aged students with disabilities who struggled with phoneme blending to read words. The effectiveness of the intervention was assessed using two multiple probe design studies across sets of words based on an onset-rime (word family) strategy. In Study 1, teacher-led instruction was paired with technology-assisted instruction for all intervention sessions for three students in first and second grade. In Study 2, teacher-led instruction occurred between baseline and technology-assisted intervention sessions for three students in third and fourth grade. During the initial instruction sessions, participants recorded their own voices onto PowerPoint slides so that their technology-assisted instruction included self-modelling. Results of both studies indicated that technology-assisted instruction can be effective for helping students learn how to blend phonemes to read words; however, performance varied and there were limitations in each study that should be addressed in future research. Relevant implications for classroom instruction are emphasized.  相似文献   
8.
基于IEC61131-3标准设计一个可编程逻辑控制器(PLC)编辑模块,并给出了主要数据结构和算法的设计。通过测试表明用户界面友好,操作简单,对后续开发具指导意义。  相似文献   
9.
The paper sets out twenty proposals for the development and evaluation of Computer Assisted Language Learning (CALL) programs. These proposals emerge from special characteristics of language instruction and of the use of computers to assist in language instruction. We combine theoretically-based assumptions with empirical findings drawn from investigation of language courseware for Hebrew speakers in Israel. We first list four unique features of language instruction: (1) the object-language-meta-language distinction; (2) computer as written medium vs. language as primary spoken medium; (3) teaching of second language skills vs. linguistics; (4) the computer as an electronic tool vs. the computer as a cognitive entity simulating the speaker. We then show how these unique characteristics of language instruction (mother-tongue and foreign language) impose special proposals on language courseware. These proposals should be observed in the development of language courseware and in the evaluation of such programs. Clearly, these proposals integrate with general courseware proposals. Michal Ephratt (Ph.D., computational linguistics) completed post-doctoral studies at the University of Rochester. She has been on the staff of the Dept. of Hebrew Linguistics, University of Haifa, since 1988. Some of her publications include Root-Pattern Array: The Main Tool of Hebrew Word Formation (Hebrew University, 1985); and What's in a Joke? in Advances in Artificial Intelligence, Natural Language and Knowledge-based Systems (Springer-Verlag, 1990).This paper is based on work the author did as a consultant in the National Courseware Evaluation Department of the Ministry of Education. I wish to thank Esther Diamant, head of the department, for making the study possible.  相似文献   
10.
针对远程开关控制技术的需求,提出一种基于GSM的远程开关控制装置设计.该装置的主要特点为使用公众GSM网络进行数据的传递,用户通过手机发送短信即可实现对设备开关的远程异地控制.详细介绍了该装置的硬件设计方案和单片机程序的设计方法,并对设计的装置进行了测试.测试与分析结果表明,设计的装置能实现远程开关控制和返回状态等各种功能,运行效果良好.  相似文献   
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