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91.
E. Georgiadou 《Cybernetics and Systems Analysis》2003,39(1):125-142
In this paper, a historical overview of significant attempts to get over the software crisis is presented. In particular, we trace the development of lifecycle models and information systems development methodologies during the last four decades. Finally, we explore the role of measurements and outline current and future works leading to process and product improvement. 相似文献
92.
复杂地质背景中的热释光应用初步研究 总被引:1,自引:0,他引:1
采用热释光光子计数的方法初步研究了鄂尔多斯盆地和安徽淮南煤田两种复杂地质背景中的热释光现象。研究结果表明:(1)深度小于1000m的浅表地层岩石标本的天然热释光量没有显著的异常,可以认为是晚第四纪以来的自然放射性效应的累加;(2)在深度2000m以上的地层,钻孔岩石标本的天然热释光统计显著呈现弱化趋势,甚至在4000m深度的岩石已经不具备生长热释光的条件;(3)岩性为石英砂岩的钻孔标本的天然热释光峰温的位置普遍移向高温方向,可以认为是该地层曾经遭受多次热事件作用的结果。 相似文献
93.
Muller Stéphanie Garda Patrick Muller Jean-Denis Crusem René Cansi Yves 《Neural Processing Letters》1998,8(1):83-91
This letter presents a method for modelling and processing incomplete data in connectionist systems. The approach consists in applying a neuro-fuzzy coding to the input data of a neural network. After an introduction to the different kinds of imperfections, we propose a neuro-fuzzy coding in order to take incomplete data into account. We show the efficiency of this coding on the problem of the classification of seismic events. The results show that a neuro-fuzzy coding of the inputs of a neural network increases the performance and classifies incomplete data with little affect on the results. 相似文献
94.
软件体系结构被看成是现代软件技术的重要因素之一 ,而一个软件系统结构的关键就是它可以分解成组件和组件交互的规格说明。扩展事件踪迹图 (ExtendedEventsTraces ,EETs)是一种用来描述组件交互的图形技术 ,它允许我们用图来定义结构中经常发生的交互模型 ,并且在多种上下文中可实例化 ,因而可以重用。虽然EETs的图形表示很直观 ,但是语义不够精确 ,因此 ,在本文中将使用形式规格说明语言Z来形式化EETs。并且 ,给出了形式描述EETs的几个应用例子 相似文献
95.
Ge Lin 《Computers, Environment and Urban Systems》2004,28(6):691
This paper compares the performance of three clustering tests––Rogerson R, Getis-Ord G and Lin-Zeng LR-T––using a range of simulated sample distributions from rare to common spatial events. It is shown that all of the tests are sensitive to high value clustering, and all but G are sensitive to low-value clustering. For a spatial pattern exhibiting negative spatial autocorrelation, R is likely to associate the autocorrelation with clustering when sample size is greater than 20, while LR-T and G are unlikely to accept any presence of negative autocorrelation as clustering. 相似文献
96.
97.
论社会主义市场经济诚信建设 总被引:1,自引:0,他引:1
何虹 《昆明冶金高等专科学校学报》2004,20(3):73-75,88
在大力发展经济之际,如何倡导有信用、讲诚信的思想价值观念,对保证政府机关的信誉权威、企业发展的稳步前进、人才资源的有效利用显得特别重要。就我国社会主义市场经济条件下,信用危机产生的原因及加强诚信建设进行探讨。 相似文献
98.
Holahan Charles J.; Moos Rudolf H.; Holahan Carole K.; Cronkite Ruth C.; Randall Patrick K. 《Canadian Metallurgical Quarterly》2004,72(2):269
This study followed baseline samples of 424 unipolar depressed patients and 424 community controls across 10 years to investigate the association between depression and alcohol-related coping and to examine how life context vulnerabilities underlie the risk for depressed individuals to rely on drinking to cope. Findings supported all hypotheses. Depressed patients engaged in more drinking to cope than did community controls. Within individuals, more negative life events and less family support were associated with more drinking to cope across the 4 observations. Depressed patients experienced more negative life events and less family support than did community controls. These underlying life context vulnerabilities explained the relationship between depressed patient status and drinking to cope. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
The discovery of conjunctive causes--factors that act in concert to produce or prevent an effect--has been explained by purely covariational theories. Such theories assume that concomitant variations in observable events directly license causal inferences, without postulating the existence of unobservable causal relations. This article discusses problems with these theories, proposes a causal-power theory that overcomes the problems, and reports empirical evidence favoring the new theory. Unlike earlier models, the new theory derives (a) the conditions under which covariation implies conjunctive causation and (b) functions relating observable events to unobservable conjunctive causal strength. This psychological theory, which concerns simple cases involving 2 binary candidate causes and a binary effect, raises questions about normative statistics for testing causal hypotheses regarding categorical data resulting from discrete variables. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
100.
This investigation examined whether cognition serves as a direct factor, mediates, or moderates the relationship between stressful life events and Children's Depression Inventory (CDI; Kovacs, 1992) factor scores in urban, ethnic minority youth. Ninety-eight middle school students completed measures of stressful life events, cognition (cognitive triad and locus of control), and depressive symptoms. Results provided support for both mediating and moderating models of depression. Specifically, the cognitive triad mediated the relationship between stressful life events and depressive symptom categories of negative mood, ineffectiveness, and anhedonia, while it interacted with stressful life events to predict negative self-esteem. In addition, locus of control was found to interact with stressful life events to predict anhedonia. Finally, the diathesis-stress model was not supported when predicting the CDI Interpersonal Problems factor score, which taps externalizing behaviors. Implications for school psychology research and practice include the importance of including measures of stressful life events and cognitive styles in assessment of children's social-emotional functioning. In addition, results highlight the need to target children's perceptions for intervention since they appear to play a significant role in psychological reactions to stressors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献