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991.
通过对大学英语网络自主学习运行环境和教学模式的研究,介绍了现有网络学习运行环境包含的各种网络结构、软件架构、学习和考核方法等几个方面,讨论了各种环境因素在实际应用中的优劣与取舍原因,给出了开放教学理念下的网络运行环境研究结果。在研究中能给学生提供充分思考的空间、促进学生在学习中的独立思考和探索精神,进而达到学生素质全面发展的目的。 相似文献
992.
城市公共交通服务质量评价知识规则是城市公共交通企业进行服务质量评价的重要依据,优质、合理的评价知识规则将使服务质量评价更加公正、更加客观。本文在分析城市公共交通服务质量评价指标体系的基础上,将一种改进的遗传算法用于城市公共交通服务质量评价价的知识规则挖掘,提出一种基于遗传算法的城市公共交通服务质量评价知识规则挖掘方法,阐述算法的实现途径。实例表明,该方法在进行知识规则挖掘时是完全可行的、有效的。 相似文献
993.
在当前社会基础和技术条件下,我国绿色水电认证工作已经具备了开展试点评价的条件。提出了在生态流域、健康河流与绿色水电三个层面的整体框架下,开展绿色水电试点评价标识工作的实施策略,即以设立"绿色水电示范项目"为切入点,编制《绿色水电评价标识管理办法(试行)》作为工作依据,通过提供财政补贴、电价补偿等激励措施,分类、分期地开展试点评价与标识工作,最终全面、规范地实施我国绿色水电认证,促进人水关系和谐,实现水电开发与生态环境的协调发展。 相似文献
994.
Kanis H 《Applied ergonomics》2011,(2):337-347
The number of usability problems discovered in a user trial or identified in a heuristic evaluation can never be claimed to be exhaustive. This raises the question of how many usability problems remained undetected. In ergonomics/human factors research this subject matter is often addressed by asking how many participants are sufficient to discover a specific proportion of the usability problems. Current approaches to answer this question suffer from various biasing mechanisms, which undermine the credibility of the popular ‘rule of thumb’ that five participants are sufficient for the discovery of 80% of ‘all’ usability problems. This 5-user rule appears to be speculative in its application as a stop rule. In this paper, I compare actual estimates of the number of usability problems. Underestimation surfaces as a permanent threat. The so-called Turing estimate (CT) appears to be the most satisfactory. However, also CT estimates may suffer from underestimation. Therefore max(CT,CF) with the CF estimate based on partitioned frequencies is proposed as the most adequate estimate of the number of usability problems in the studies presented. 相似文献
995.
Mu-Yen Chen 《Information Sciences》2011,181(18):3861-3877
Real options can be a powerful tool for quantifying the value of strategic and operational flexibility associated with uncertain IT investments. They also constitute a new way of thinking as to how knowledge management (KM) can be implemented and managed to maximize the upside potential while minimizing any downside risk. This paper explored how practitioners can incorporate options analysis into contemporary knowledge management. Options analysis is recognizing real options and then determines how they add value. The main issue here is to manage knowledge so that the theoretical option value is realized in practice. This paper developed a new metric, knowledge management performance index (KMPI), for evaluating the performance of a firm in its KM at any given point in time as follows: knowledge creation, knowledge conversion, knowledge circulation and knowledge completion. The higher the efficiency of the KM process, the higher the KMPI, thereby is enabling firms to become increasingly knowledgeable. To prove the contribution of the KMPI, a questionnaire survey was conducted among 121 firms listed on the Taiwan Stock Exchange Corporation (TSEC). This paper makes five important contributions: (1) it shows that if the KM process improves, the KMPI is enhanced. This finding is based on a survey of the questionnaires. As a result, the KMPI can effectively and efficiently represent the KM process; (2) it shows that when the KMPI increases, a company’s performance will be enhanced in five different areas This indicates a significant relationship between the KMPI and the company’s performance; (3) it also shows that the higher the KMPI, the higher the performance of the organization. This is especially valuable to any organization where knowledge is not being used optimally; (4) it provides an option analysis that may be helpful to managers for making the right decision in an uncertain environment; and (5) it presents the first application of the Black-Scholes model to use an actual business situation involving KM as its test bed. The results proved that the option pricing model can act as a measurement guideline for the entire knowledge of the whole company. 相似文献
996.
Suitability evaluation of urban construction land based on geo-environmental factors of Hangzhou, China 总被引:4,自引:0,他引:4
Kai XuChunfang Kong Jiangfeng LiLiqin Zhang Chonglong Wu 《Computers & Geosciences》2011,37(8):992-1002
Suitability evaluation of urban construction land based on geo-environmental factors is the process of determining the fitness of a given tract of land for construction. This process involves a consideration of the geomorphology, geology, engineering geology, geological hazards, and other geological factors and is the basis of urban construction land planning and management. With the support of Geographic Information Systems (GIS), grid analysis, and geo-spatial analysis techniques, four factor groups comprising nine separate subfactors of geo-environmental attributes were selected to be used in the evaluation of the suitability level for construction land in Hangzhou. This was based on K-means clustering and back-propagation (BP) neural network methods due to their advantages in fast computing, unique adaptive capacity, and self-organization. Simultaneously, the evaluation results based on K-means clustering and BP neural network were compared and analyzed, and the accuracy evaluation was set. The results showed that the geo-environmental suitability evaluation results of construction land based on K-means clustering and BP neural network were similar in terms of the distribution and scale of construction land suitability level. At the same time, the results of the two evaluation methods were consistent with the variability in suitability level, engineering geology, and hydrogeology of Hangzhou. The results also showed that the real advantage of the methods proposed in this paper lies in their capacity to streamline the mapping process and to ensure that the results are consistent throughout. The suitability level of the urban construction land based on the geo-environment in Hangzhou was divided into four construction sites: land for building super high-rise and high-rise buildings, land for building multistorey buildings, land for low-rise buildings, and nonbuilding land. The results of the suitability evaluation for each category will provide a scientific basis for decision-making in urban development in Hangzhou. 相似文献
997.
Licheng XueAuthor Vitae Feng ShiAuthor VitaeWeixing JiAuthor Vitae Haroon-Ur-Rashid KhanAuthor Vitae 《Microprocessors and Microsystems》2011,35(5):484-495
Network-on-Chip (NoC) architectures have been adopted by chip multi-processors (CMPs) as a flexible solution to the increasing delay in the deep sub-micron regime. However, the shrinking feature size limits the performance of NoCs due to power and area constraints. In this paper, we propose three 3D floorplanning methods for a Triplet-based Hierarchical Interconnection Network (THIN) which is a new high performance NoC. The proposed floorplanning methods use both Manhattan and Y-architecture routing architectures so as to improve the performance, reduce the power consumption and area requirement of THIN. A cycle accurate simulator was developed based on Noxim NoC simulator and ORION 2.0 energy model. The proposed floorplanning methods show up to 24.69% energy and 8.84% area reduction at best compared with 3D Mesh. Our analysis concludes that THIN is not only a feasible but also a low-power and area-efficient NoC at physical level. 相似文献
998.
Da Yong Zhang Author VitaeYong ZengAuthor Vitae Lingyu Wang Author VitaeHongtao Li Author Vitae Yuanfeng Geng Author Vitae 《Computers in Industry》2011,62(3):351-363
While information sharing can benefit supply chains significantly, it may also have an adverse effect, namely, information leakage. A limitation common to many existing solutions for preventing information leakage in supply chains is that they rely, either implicitly or explicitly, upon two unrealistic assumptions. First, what information is confidential is well known. Second, confidential information will not be revealed, if only it is not shared, regardless of how much other information is being shared. As we shall show in this paper, those assumptions are not always true due to potential information leakage caused by inferences. Specifically, we propose a conceptual model of such information leakage. The model will enable companies in a supply chain to better understand how their confidential information may be leaked through inferences. On the basis of the proposed conceptual model, we then devise a quantitative approach to evaluating the risk of information leakage caused by inferences when a given amount of information is shared. The quantitative approach will allow companies in a supply chain to measure and consequently mitigate the risk of information leakage. Finally, we discuss a case study to illustrate how the proposed approaches work in practice. 相似文献
999.
In LeeAuthor Vitae 《Decision Support Systems》2011,51(1):230-239
While e-recruiting has been widely adopted as one of the most successful e-business applications, it constitutes an under-researched area in e-business research. This study reviews the integration issues in e-recruiting and presents an e-recruiting integration decision model. The benefits of the investment in e-recruiting process integration are discussed in comparison to separate e-recruiting investments. We show that the optimal investment in the e-recruiting process integration results in a lower total cost than the separate e-recruiting investments. In addition, in light of the widely practiced resource constrained investments, we present the method of Lagrange multipliers which is used to find the optimal investment under a budget constraint. 相似文献
1000.
Viara PopovaAuthor Vitae 《Data & Knowledge Engineering》2011,70(4):335-364
Every organisation exists or is created for the achievement of one or more goals. To ensure continued success, the organisation should monitor its performance with respect to the formulated goals. In practice the performance of an organisation is often evaluated by estimating its performance indicators. In most existing approaches for organisation modelling the relation between performance indicators and goals remains implicit. This paper proposes a formal framework for modelling goals based on performance indicators and defines mechanisms for establishing goal satisfaction, which enable evaluation of organisational performance. Methodological and analysis issues related to goals are also discussed in the paper. The described framework is a part of a general framework for organisation modelling and analysis. 相似文献