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31.
Well-known epistemologies of science have implications for how best to understand knowledge transfer (KT). Yet, to date, no serious attempt has been made to explicate these particular implications. This paper infers views about KT from two popular epistemologies; what we characterize as incommensurabilitist views (after Devitt, 2001; Bird, 2002, 2008; Sankey and Hoyningen-Huene 2013) and voluntarist views (after Van Fraassen, 1984; Dupré, 2001; Chakravartty, 2015). We argue views of the former sort define the methodological, ontological, and social conditions under which research operates within ‘different worlds’ (to use Kuhn's expression), and entail that genuine KTs under those conditions should be difficult or even impossible. By contrast, more liberal voluntarist views recognize epistemological processes that allow for transfers across different sciences even under such conditions. After outlining these antithetical positions, we identify two kinds of KTs present in well-known episodes in the history of ecology—specifically, successful model transfers from chemical kinetics and thermodynamics into areas of ecological research—which reveal significant limitations of incommensurabilitist views. We conclude by discussing how the selected examples support a pluralistic voluntarism regarding KT. 相似文献
32.
C3I系统理论研究概况 总被引:3,自引:0,他引:3
罗雪山 《系统工程与电子技术》1999,21(12)
简要回顾了 C3 I系统理论发展历史 ,详细讨论了 C3 I系统理论的主要研究内容和发展趋势 ,最后介绍了影响 C3 I系统理论的几个问题与因素以及对 C3 I系统理论的要求。 相似文献
33.
The paper examines philosophical issues that arise in contexts where one has many different models for treating the same system. I show why in some cases this appears relatively unproblematic (models of turbulence) while others represent genuine difficulties when attempting to interpret the information that models provide (nuclear models). What the examples show is that while complementary models needn’t be a hindrance to knowledge acquisition, the kind of inconsistency present in nuclear cases is, since it is indicative of a lack of genuine theoretical understanding. It is important to note that the differences in modeling do not result directly from the status of our knowledge of turbulent flows as opposed to nuclear dynamics—both face fundamental theoretical problems in the construction and application of models. However, as we shall, the ‘problem context(s)’ in which the modeling takes plays a decisive role in evaluating the epistemic merit of the models themselves. Moreover, the theoretical difficulties that give rise to inconsistent as opposed to complementary models (in the cases I discuss) impose epistemic and methodological burdens that cannot be overcome by invoking philosophical strategies like perspectivism, paraconsistency or partial structures. 相似文献
34.
Though it is held that some models in science have explanatory value, there is no conclusive agreement on what provides them with this value. One common view is that models have explanatory value vis-à-vis some target systems because they are developed using an abstraction process (i.e., a process which involves omitting features). Though I think this is correct, I believe it is not the whole picture. In this paper, I argue that, in addition to the well-known process of abstraction understood as an omission of features or information, there is also a family of abstraction processes that involve aggregation of features or information and that these processes play an important role in endowing the models they are used to build with explanatory value. After offering a taxonomy of abstraction processes involving aggregation, I show by considering in detail several models drawn from different sciences that the abstraction processes involving aggregation that are used to build these models are responsible (at least partially) for their having explanatory value. 相似文献
35.
A distinction is made between theory-driven and phenomenological models. It is argued that phenomenological models are significant means by which theory is applied to phenomena. They act both as sources of knowledge of their target systems and are explanatory of the behaviors of the latter. A version of the shell-model of nuclear structure is analyzed and it is explained why such a model cannot be understood as being subsumed under the theory structure of Quantum Mechanics. Thus its representational capacity does not stem from its close link to theory. It is shown that the shell model yields knowledge about the target and is explanatory of certain behaviors of nuclei. Aspects of the process by which the shell model acquires its representational capacity are analyzed. It is argued that these point to the conclusion that the representational status of the model is a function of its capacity to function as a source of knowledge and its capacity to postulate and explain underlying mechanisms that give rise to the observed behavior of its target. 相似文献
36.
37.
隐马尔可夫模型及在人脸识别算法中的应用 总被引:1,自引:0,他引:1
李涛 《达县师范高等专科学校学报》2005,15(2):51-54
介绍了隐马尔可夫模型(HMM)及其三大算法,并将其引入人脸识别的研究中,描述了一种基于隐马尔可夫模型的人脸识别方法.一幅正面人脸图像的重要特征具有一定的顺序,它可以通过一维的HMM来建模,每个特征区域被指定为一个状态,通过K-L变换将降维以后的特征矢量作为观察矢量.和其他人脸识别的方法比较,隐马尔可夫模型更能为人脸检测和识别提供灵活的框架. 相似文献
38.
39.
蒸汽驱采油物理模型研究(一) 总被引:2,自引:0,他引:2
本文用蒸汽驱采油真空物理模型对克拉玛依油田九区七点井网的蒸汽驱采油进行了研究。以相似理论为基础设计建造了模型,研究了蒸汽注入率、干度、生产压力对蒸汽驱性能的影响。实验结果表明,干度、注入率对采收率有显著影响,且在相同能量注入率情况下,干度影响大于注入率。根据油层温度场分析推论,对于中质薄油藏,蒸汽超覆有利于提高采收率和能量注入率。本文介绍了将实际油藏按比例转换为室内模型的相似准则,讨论了原型向模型的转换原则,论述了物理模型实验的流程及模型的制作工艺。 相似文献
40.
VMS诱导信息影响下的路径选择行为分析 总被引:5,自引:0,他引:5
正确理解可变情报板(VMS)诱导信息影响下的驾驶员路径选择行为,是高效发挥VMS作用的必然要求.采用SP调查(意向调查)探索VMS同时提供快速路和替换路径行程时间条件下的路径选择行为,采用离散选择分析方法对影响路径选择的因素进行了多变量分析,建立了描述路径选择概率的二元probit模型.Probit模型中的行程时间节省量这一解释变量的系数视为服从对数正态分布的随机系数,以反映行程时间重要性在人群中的不纯一性(heterogeneity).分析表明,驾驶员的路径选择会受VMS诱导信息显著影响,VMS影响大小取决于VMS信息内容、驾驶员个体属性(年龄、驾龄、用车类型以及快速路使用频率)、以及替换路径属性(所含信控交叉口数目).具体地,(a)VMS所告知的行程时间节省量越大.改道可能性越大;(b)年轻和年长者较之中等年龄者,改道可能性更大;驾龄越长,改道可能性越大;非单位公车驾驶员改道可能性更大;使用快速路频率越低,改道可能性越大,(c)替换路径所含信控交叉口越多,改道可能性越小.研究成果可为更好地设计、运行和评价VMS信息发布策略提供参考. 相似文献