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101.
ZHENG Geng-zhong 《数字社区&智能家居》2008,(11)
根据《计算机组成原理》课程的特点,在对建构主义理论分析的基础上,将《计算机组成原理》教学与建构主义理论相结合,对基于建构主义理论的《计算机组成原理》课程的教学改革进行了探讨和分析,有利于进一步提高教学质量,培养学生良好的《计算机组成原理》教学素养和创新意识。 相似文献
102.
Yufei Tao Xiaokui Xiao 《The VLDB Journal The International Journal on Very Large Data Bases》2008,17(5):1253-1270
The existing predictive spatiotemporal indexes can be classified into two categories, depending on whether they are based
on the primal or dual methodology. Although we have gained considerable empirical knowledge about various access methods, currently there is only
limited understanding on the theoretical characteristics of the two methodologies. In fact, the experimental results in different
papers even contradict each other, regarding the relative superiority of the primal and dual techniques. This paper presents
a careful study on the query performance of general primal and dual indexes, and reveals important insight into the behavior
of each technique. In particular, we mathematically establish the conditions that determine the superiority of each methodology,
and provide rigorous justification for well-known observations that have not been properly explained in the literature. Our
analytical findings also resolve the contradiction in the experiments of previous work. 相似文献
103.
Interorganizational systems (IOS) may provide substantial benefits, however many organizations are reluctant to implement
them. This empirical research takes a novel approach and develops a model of IOS feasibility, which is based on the Theory
of Constraints (TOC). It introduces the notion of maximal infeasibility, which is the highest among the values of five factors:
economic infeasibility, organizational infeasibility, technological infeasibility, risks, and lack of financial resources.
The highest value was selected because implementation is hindered even if only one of the feasibility requirements is not
fulfilled. Data collected from 139 medium and large Israeli business organizations validated the model, and indicated that
strategic motivation is the main driving force for an organization to initiate or to join an IOS, while the main barriers
are organizational infeasibility issues such as lack of management support or uninterested potential partners. Adopting a
TOC approach to IOS implementation may assist organizations to overcome these obstacles and increase the chance of a successful
implementation.
An earlier shorter version of this paper was presented at WEB 2006, a pre-ICIS workshop on e-business, in Milwaukee, WI. 相似文献
104.
We consider the classes of ⊕-codes and ⊗-codes, which are superclasses of outfix and hyper-codes, respectively. These restrictions are based on the synchronized insertion operation, which serves as a model for the gene rearrangement function in certain unicellular organisms. We investigate the classes of ⊕-codes and ⊗-codes from a theoretical perspective, examine their relationships with traditional code classes and consider related decidability problems. 相似文献
105.
认知灵活性理论指导下的网络教学交互设计 总被引:1,自引:0,他引:1
本文首先介绍了认知灵活性理论的涵义及其关于学习和教学的观点;探讨了认知灵活性理论对开展网络教学交互设计的启发性意义;从"人-机"交互和"人-人"交互两个方面,探究了认知灵活性理论柏导下的网络教学系统中的交互设计。 相似文献
106.
We propose a semantics for the -quantifier of Miller and Tiu. First we consider the case for classical first-order logic. In this case, the interpretation is close to standard Tarski-semantics and completeness can be shown using a standard argument. Then we put our semantics into a broader context by giving a general interpretation of in categories with binding structure. Since categories with binding structure also encompass nominal logic, we thus show that both -logic and nominal logic can be modelled using the same definition of binding. As a special case of the general semantics in categories with binding structure, we recover Gabbay & Cheney's translation of FOλ into nominal logic. 相似文献
107.
首先讨论了E-mail营销的产生和理论基础,然后分析了客户数据库的建立与使用,最后,对增强E-mail营销效果的对策进行了研究。 相似文献
108.
阐述了以江泽民同志为核心的党的第三代领导集体,继承和发展了马克思列宁主义、毛泽东思想,在分析、研究、解决改革开放和社会主义现代化建设面临的新情况、新问题的过程中,从六个方面创造性地坚持和发展了邓小平理论. 相似文献
109.
中科院声学所知识创新工程项目基于内容分析的中文问答处理算法及系统实现* 总被引:4,自引:1,他引:3
提出了一种基于HNC自然语言理解框架下的中文问答处理算法,并在此算法基础上加以系统实现。试验证明,该系统在中等规模常识库基础上效果显著、准确率高。 相似文献
110.
Naoki Abe 《New Generation Computing》1991,8(4):319-335
We consider the problem of learning the commutative subclass of regular languages in the on-line model of predicting {0,1∼-valued
functions from examples and reinforcements due to Littlestone [7,4]. We show that the entire class of commutative deterministic
finite state automata (CDFAs) of an arbitrary alphabet sizek is predictable inO(s
k) time with the worst case number of mistakes bounded above byO(s
kk logs), wheres is the number of states in the target DFA. As a corollary, this result implies that the class of CDFAs is also PAC-learnable
from random labeled examples in timeO(s
k) with sample complexity, using a different class of representations. The mistake bound of our algorithm is within a polynomial, for a fixed alphabet
size, of the lower boundO(s+k) we obtain by calculating the VC-dimension of the class. Our result also implies the predictability of the class of finite
sets of commutative DFAs representing the finite unions of the languages accepted by the respective DFAs.
Part of this work was supported by the Office of Naval Research under contract number N00014-87-K-0401 while the author was
at the Department of Computer and Information Science, University of Pennsylvania, and N0014-86-K-0454 while at the Department
of Computer and Information Sciences, U.C. Santa Cruz. The author’s email address is abe@IBL.CL.nec.co.jp 相似文献