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排序方式: 共有136条查询结果,搜索用时 15 毫秒
31.
A problem in expert systems is typically represented by an AND/OR graph. A set of spatial light modulators which can perform AND and OR logic operations can directly be applied to form an optical inference engine. The threshold-dependence logic operations of relatively low contrast and small dynamic range liquid crystal television are explained. The parallel inference architecture operated by liquid crystal televisions is presented. 相似文献
32.
Vitalii Emelianov Nataliia Emelianova Anton Zhilenkov Sergei Chernyi 《Entropy (Basel, Switzerland)》2021,23(1)
An information model is outlined, which represents an intelligent system of metallographic analysis in the form of a set of subsystems, the interaction of which ensures the performance of metallographic analysis functions. The structure of the information storage subsystem for metallographic analysis is presented. The deployment model of an intelligent metallographic analysis system is proposed and described. The paper outlines the approach to the presentation of an expert subsystem for metallographic quality control of metals based on a neural network. The process of finding a close precedent in metallographic analysis with reference to a multilayer neural network is described. An intelligent metallographic analysis system is described, which based on proposed information model. A specialized software of an intelligent metallographic analysis system is presented. The functioning results of the developed system for processing images of steel microstructures to determine the steel quantitative parameters is presented. 相似文献
33.
针对目前血液分析仪无法自动诊断血液疾病的现状,提出了一种应用于血液分析仪的专家诊断系统。本系统在传统专家系统结构的基础上进行了改进,以专家经验、国际血液学复检专家组推荐的复检规则以及临床案例为知识源,利用关系型数据库技术设计出一种产生式树形结构的知识库,并结合Snort规则库中的三维链表数据结构对知识库进行优化,最终完成了血液分析仪专家诊断系统的研制。实验结果:系统诊断的假阳性率为2.7%,假阴性率为3.31‰。结论:本文提出的专家诊断系统具有推理灵活、实时性好的特点。 相似文献
34.
Miguel Peris 《Analytica chimica acta》2002,454(1):1-11
This paper presents an overview of the most relevant contributions in the field of expert system (ES) applications in chemical analysis of foods, along with a critical discussion of future, would-be developments. It illustrates the possibilities offered as well as the fact that quality control laboratories should be aware of the power of artificial intelligence that modern computer technology affords. It is worth noting that the applications described are straightforward with a certain versatility and can, therefore, be implemented for other analytes and/or food samples. Special attention is devoted to the promising distributed knowledge-based systems due to their potential advantages over the existing centralized approaches, as inferred from a recent example of application to the on-line monitoring of some key chemical parameters in the course of a food production process. Short and middle term predictions concerning the potential of ES in food analysis are also made. 相似文献
35.
本文论述ZES的功能和开发技术。描述了系统中推理的数学模型及其理论基础,最后阐述了ZES的外壳可用作建造中医专家系统的工具。 相似文献
36.
An eigenvalue method on group decision 总被引:5,自引:0,他引:5
邱菀华 《应用数学和力学(英文版)》1997,18(11):1099-1104
I.ThePrincipleofGEMInthefollowing,wewi1levaluatenobjectsB,,B1,"-,B,bygroupdecisionsupportsystemGwhichconsistsofmexpertsS,,S,,..',S..Letx',E[I,J](f=1,2'...,mlj=l,2,"',n)betheevaluationvalueofthejthobjectBjestimatedbythei-tllexpertS'.Thelargerxqis,themoreop… 相似文献
37.
Milind Kandlikar Gurumurthy Ramachandran Andrew Maynard Barbara Murdock William A. Toscano 《Journal of nanoparticle research》2007,9(1):137-156
Uncertainties in conventional quantitative risk assessment typically relate to values of parameters in risk models. For many
environmental contaminants, there is a lack of sufficient information about multiple components of the risk assessment framework.
In such cases, the use of default assumptions and extrapolations to fill in the data gaps is a common practice. Nanoparticle
risks, however, pose a new form of risk assessment challenge. Besides a lack of data, there is deep scientific uncertainty
regarding every aspect of the risk assessment framework: (a) particle characteristics that may affect toxicity; (b) their
fate and transport through the environment; (c) the routes of exposure and the metrics by which exposure ought to be measured;
(d) the mechanisms of translocation to different parts of the body; and (e) the mechanisms of toxicity and disease. In each
of these areas, there are multiple and competing models and hypotheses. These are not merely parametric uncertainties but
uncertainties about the choice of the causal mechanisms themselves and the proper model variables to be used, i.e., structural
uncertainties. While these uncertainties exist for PM2.5 as well, risk assessment for PM2.5 has avoided dealing with these
issues because of a plethora of epidemiological studies. However, such studies don’t exist for the case of nanoparticles.
Even if such studies are done in the future, they will be very specific to a particular type of engineered nanoparticle and
not generalizable to other nanoparticles. Therefore, risk assessment for nanoparticles will have to deal with the various
uncertainties that were avoided in the case of PM2.5. Consequently, uncertainties in estimating risks due to nanoparticle
exposures may be characterized as ‘extreme’. This paper proposes a methodology by which risk analysts can cope with such extreme
uncertainty. One way to make these problems analytically tractable is to use expert judgment approaches to study the degree
of consensus and/or disagreement between experts on different parts of the exposure–response paradigm. This can be done by
eliciting judgments from a wide range of experts on different parts of the risk causal chain. We also use examples to illustrate
how studying expert consensus/disagreement helps in research prioritization and budget allocation exercises. The expert elicitation
can be repeated over the course of several years, over which time, the state of scientific knowledge will also improve and
uncertainties may possibly reduce. Results from expert the elicitation exercise can be used by risk managers or managers of
funding agencies as a tool for research prioritization. 相似文献
38.
An extension of probabilistic PERT/CPM is proposed as a framework for soliciting expert opinion to characterize random variables for stochastic treatment in simulation models. By eliciting minimum, modal, ninetieth percentile, and maximum estimates, the distribution of variables with probability density functions of beta form can be explicitly characterized without relying on the traditional, but empirically unverified, assumption of a standard deviation equal to one-sixth of the range. This practical and inexpensive technique is illustrated by application to a wildfire protection planning problem – estimating the time required to produce a given length of fireline by different firefighting resources under diverse conditions. The estimated production times are an essential input to a planning model of initial attack on wildland fires used by the California Department of Forestry and Fire Protection, and provide that agency with useful rules-of-thumb for use in firefighter training. 相似文献
39.
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