共查询到18条相似文献，搜索用时 515 毫秒
1.
An integrated intelligent management is presented to help organizations manage many heterogeneous resources in their information system. A general architecture of management for information system reliability is proposed, and the architecture from two aspects, process model and hierarchical model, described. Data mining techniques are used in data analysis. A data analysis system applicable to real-time data analysis is developed by improved data mining on the critical processes. The framework of the integrated management for information system reliability based on real-time data mining is illustrated, and the development of integrated and intelligent management of information system discussed. 相似文献
2.
A cluster analyzing algorithm based on grids is introduced in this paper,which is applied to data mining in the city emergency system. In the previous applications, data mining was based on the method of analyzing points and lines, which was not efficient enough in dealing with the geographic information in units of police areas. The proposed algorithm maps an event set stored as a point set to a grid unit set, utilizes the cluster algorithm based on grids to find out all the clusters, and shows the results in the method of visualization. The algorithm performs well when dealing with high dimensional data sets and immense data. It is suitable for the data mining based on geographic information system and is supportive to decision-makings in the city emergency system. 相似文献
3.
一体化电子式电流电压互感器研究 总被引：7，自引：1，他引：7
A high-performance current and voltage measurement system has been developed in power system.The system is composed of two parts:one current measurement element and one voltage measurement element.A Rogowski coil and a capacitive voltage divider are used respectively for the line current and voltage measurements.Active electronic components are used to modulate signal,and power supply for these components is drawn from power line via an auxiliary current transformer,Measurement signal is transmitted y optical fibers,which is resistant to electromagnetic induction and noise,With careful design and the use of digital signal processing technology,the whole system can meet 0.5% accuracy for metering and provides large dynamic range coupled with good accuracy for protective relaying use. 相似文献
4.
Ram Bahal Monika Wason Sudeep 《美中教育评论》2006,3(5):58-65
Looking the progress of cyber based information system in railways, air ways, commercial institutions, industries, medical institutions etc. a pertinent questions is raised that why not in agriculture？ It is however, realized that due to short supply of extension workers, their lower educational level and least per capita extension expenditure, the demand based extension services are not been provided to different kinds of clients. Due to diversification of agriculture, the needs are varying from farmer to farmer and area to area. Farmers need different calculated feasible, viable and economical practices to follow for better output and income. The socio-economic and agro-climatic situation of farmers in the same village is also different. Therefore, demand based extension services cannot be possible through our conventional system of extension with the available human and financial resources. So far, extension agents give the information what ever they know and not that what the farmers need. It is therefore suggested to develop cyber based extension system in our country, which provides all required information about all possible questions of the farmers. Keeping this point in view, an effort was made to develop an Expert System of Extension at Division of Agricultural Extension, Indian Agricultural Research Institute New Dlehi-12. The system was built in two phases. In the first phase the agricultural information of the selected crops have been collected from the authentic sources and stored in the form of a database. In the second phase, the decision rules were formulated and coded in the expert system. Both these phases are finally combined to form cyber-based expert system, which is hosted on the Internet for the use of the farmers and general public. This is a best combination of man and machine for efficiency and need to based on dissemination at a time to all farmers. 相似文献
5.
The purpose of using life extending control for Black Hawk UH-60 helicopter is to make a trade-off between the handling qualities and the service life of critical components. An increase in service life span results in enhanced safety and the reduction in maintenance costs. This paper presents a design methodology of life extending control for structural durability and high performance of mechanical system, which is based on an explicit dynamic inversion control scheme. A real-time nonlinear fatigue crack growth model is built to predict fatigue damage resulting from the impact of cyclic bending stress on rotor shaft, which serves as an indicator of service life. The 4-axis gain- scheduled flight controller, whose gains are adjusted as a function of damage and flight velocity, is designed to regu- late roll attitude, pitch attitude, vertical velocity and yaw rate. The nonlinear system simulation results show that the responses can meet the requirements on ADS-33 Level 1 handling qualities and that the 4-axis decoupling control is realized. As the damage increases, the tracking performance is slightly degraded, which results in smaller transients in bending moment response. 相似文献
6.
Design patterns are micro architectures that have proved to be reliable,robust and easy to implement.Detecting design pattern from source code of object-oriented system can help a designer,a developer or a maintainer to understand the software system.In this paper,a new method is provided which can detect design patterns from source code combining both static and dynamic analysis.To acquire the run-time dynamic information of software systems,a code instrumentation method is adopted.At the same time,all static and dynamic information is presented in UML diagrams format.The pattern detection process and its detection results are visual and interactive.This method is tested on a call center and a traffic simulation system.Experimental results prove that the method is effective in design patterns detection. 相似文献
7.
刘继承 《重庆大学学报(英文版)》2005,4(2):90-95
1 Introduction 1 A great deal of models have been studied on the subject of Diffserv, including static and dynamic pricing schemes. In the case of dynamic pricing, the network administrators adapt the link price to the bandwidth changes; In static pricing, the price is set based on the analysis from the historical data , and it is impossible to react to the changes in the demand or traffic load of the network. However, this scheme is easier to implement. Generally, there always exists an equi… 相似文献
8.
The space sheet for a solar array structure is large in dimension, and flexible to induce complex distortion. It is difficult to measure the distortion. A large-scale flexible test prototype system is built for sheet structure vibration monitoring based on the vibration information of the solar array in space. The system provides an intelligent test method for flexible space structure with embedded sensors and non-visualization reinstruction. Multiple fiber Bragg grating （FBG） sensors are packaged and embedded into the structure with spatial division multiplexing （SDM） and wavelength division multiplexing （WDM）. The sensor interrogator distinguishes wavelength shifts that can be turned into curvature of the curve. The structure shape is reconstructed based on the curvature information and the arc-length, and then displayed. The experiment shows that the system has a high FBG sensitivity. The reconstruction algorithm is fast with high precision. The system has great potential for use in health monitoring of the space sheet structure. 相似文献
9.
This paper deals with an important subject of rejecting the abnormal dataintelligently in the dynamic data system.Based on the principle of nearest neighbor of fuz-zy mathematics,an approach of mathematically abstracting the human thinking and phys-ical practice knowledge is discussed,a new method of automatic rejection of abnormal da-ta is then proposed.The experimental results show that the method is available to the practice. 相似文献
10.
11.
Kumar Laxman 《Instructional Science》2011,39(6):881-900
Solving real-world problems is an effective learning activity that promotes meaningful learning in formal educational settings.
Problems can be classified as being either well structured or ill structured. Internet information search approaches have
an influential role to play in the successful performance of problem solving. A better understanding of how students differentially
model information search strategies and movements in tackling well- and ill-structured problems is essential for creating
engaging problem-solving environments for students. Static measures, such as the number of accessed nodes or links, or the
number of times particular web browser function buttons are clicked, are limited in their ability to analyze attributes of
information search patterns. A more dynamic and spatial representation of web movements and navigational patterns can be realized
through the use of navigational paths as data. The two path-specific structural metrics that can be used to assess network-based
navigational paths in relation to the structuredness of the problem-solving task are compactness and stratum. These metrics are, respectively, the indicators of the connectedness and linearity of network-based structures defining students’ online navigational visitations during the problem-solving sessions. This
study explored the relevance and utility of these two metrics in analyzing the navigational movements of learners in seeking
out electronic information to accomplish successful problem solving. The outcome findings of this study show that well- and
ill-structured problems demand different cognitive and information seeking navigational approaches. The differing values of
the two path metrics in analyzing the search movements organized by students in attending to well- and ill-structured problems
were a direct result of the contrasting patterns of navigational path movements. The search patterns associated with well-structured
problem solving tended to be more linear and less connected, whereas those related to ill-structured problem solving were
more distributed and inter-connected. 相似文献
12.
A. Mark Langan Nick Scott Shobana Partington Agnieszka Oczujda 《Journal of Further & Higher Education》2017,41(1):16-29
Institutions are understandably interested in the profile of their own reputations based upon publicly available data about student experiences. The UK’s National Student Survey (NSS) metrics are integrated into several ‘Good University’ calculations, whereas teaching teams most often use the survey’s text comments to change practices, rather than the metrics directly. There is little information about how messages from the national survey’s text comments relate to the accompanying numerical ratings, partly because text comments are confidential to the institution and unavailable for wide-scale research. We categorised institutional NSS text comments into themes that mirrored those of the original questionnaire. Comparisons were made between frequencies of thematic comments and the national ratings of satisfaction for several subject areas. For the first time, we demonstrate broad agreement between comments about measures of teaching staff and course organisation with the performance of the subject areas (compared to metrics of their national counterparts). These findings are consistent with previous quantitative models predicting the most important factors that most influence overall satisfaction ratings. We intend this study to be a catalyst for other institutions to explore their non-publicly available, textual returns in a similar way. The outcomes of this type of work are pertinent to all countries that use large-scale surveys. However, institutions will need to release findings to a public audience if we are to gain a national/international perspective on this key linkage between publicly available metrics and the associated text comments. 相似文献
13.
基于云计算信息检索课程网络教学系统初探 总被引：1，自引：0，他引：1
近年来,云计算已经成为网络服务领域中的研究热点。为了将云计算的理念服务于当前高等教育,结合信息检索课程特点及性质,提出了基于云计算的网络教学系统参考框架,简要介绍了框架的主要构成及功能,并根据实例分析云计算辅助教学与传统教学的优势。 相似文献
14.
数字地籍成果是现阶段我国珍贵的城市基础信息，如何对其进行综合利用是目前需要进行深入研究的课题．探讨了以地籍管理信息系统(CIS)及其数字地籍成果为基础的城市地价动态监测系统的模式，论述了进行城市地价动态监测的基本要求，设计了系统的功能模块和系统结构． 相似文献
15.
A Comparison of Experimental and Observational Approaches to Assessing the Effects of Time Constraints in a Medical Licensing Examination 
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下载免费PDF全文 Polina Harik Brian E. Clauser Irina Grabovsky Peter Baldwin Melissa J. Margolis Deniz Bucak Michael Jodoin William Walsh Steven Haist 《Journal of Educational Measurement》2018,55(2):308-327
Test administrators are appropriately concerned about the potential for time constraints to impact the validity of score interpretations; psychometric efforts to evaluate the impact of speededness date back more than half a century. The widespread move to computerized test delivery has led to the development of new approaches to evaluating how examinees use testing time and to new metrics designed to provide evidence about the extent to which time limits impact performance. Much of the existing research is based on these types of observational metrics; relatively few studies use randomized experiments to evaluate the impact time limits on scores. Of those studies that do report on randomized experiments, none directly compare the experimental results to evidence from observational metrics to evaluate the extent to which these metrics are able to sensitively identify conditions in which time constraints actually impact scores. The present study provides such evidence based on data from a medical licensing examination. The results indicate that these observational metrics are useful but provide an imprecise evaluation of the impact of time constraints on test performance. 相似文献
16.
Classes are key software components in an object-oriented software system. In many industrial OO software systems,there are some classes that have complicated structure and relationships. So in the processes of software maintenance,testing,software reengineering,software reuse and software restructure,it is a challenge for software engineers to understand these classes thoroughly. This paper proposes a class comprehension model based on constructivist learning theory,and implements a software visualization tool(MFV-Class)to help in the comprehension of a class. The tool provides multiple views of class to uncover manifold facets of class contents. It enables visualizing three object-oriented metrics of classes to help users focus on the understanding process. A case study was conducted to evaluate our approach and the toolkit. 相似文献
17.
INTRODUCTION The increasingly complex and large number ofsoftware products in today’s software industrymakes the tasks of software maintenance, softwarereuse and software restructuring more and moredifficult. With the popularity of the object-orientedprogramming paradigm, the ability to reverse en-gineer and understand object-oriented legacy sys-tems has become an important problem to be ad-dressed. In the object-oriented reverse engineering(OORE) research area, most researchers f… 相似文献
18.
Carl-Johan Rundgren Lena A. E. Tibell 《International Journal of Science and Mathematics Education》2010,8(2):223-246
Images, diagrams, and other forms of visualization are playing increasingly important roles in molecular life science teaching
and research, both for conveying information and as conceptual tools, transforming the way we think about the events and processes
the subject covers. This study examines how upper secondary and tertiary students interpret visualizations of transport through
the cell membrane in the form of a still image and an animation. Twenty upper secondary and five tertiary students were interviewed.
In addition, 31 university students participated in a group discussion and answered a questionnaire regarding the animation.
A model, based on variation theory, was then tested as a tool for distinguishing between what is expected to be learned, what
is present in the visualizations, and what is actually learned by the students. Three critical features of the ability to
visualize biomolecular processes were identified from the students’ interpretations of the animation: the complexity of biomolecular
processes, the dynamic and random nature of biomolecular interactions, and extrapolation between 2D and 3D. The results of
this study support the use of multiple representations to achieve different learning goals. 相似文献