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941.
Performance analysis of security aspects by weaving scenarios extracted from UML models 总被引:1,自引:0,他引:1
Murray Woodside Author Vitae Dorin B. Petriu Author Vitae 《Journal of Systems and Software》2009,82(1):56-74
Aspect-oriented modeling (AOM) allows software designers to describe features that address pervasive concerns separately as aspects, and to systematically incorporate the features into a design model using model composition techniques. The goal of this paper is to analyze the performance effects of different security features that may be represented as aspect models. This is part of a larger research effort to integrate methodologies and tools for the analysis of security and performance properties early in the software development process. In this paper, we describe an extension to the AOM approach that provides support for performance analysis. We use the performance analysis techniques developed previously in the PUMA project, which take as input UML models annotated with the standard UML Profile for Schedulability, Performance and Time (SPT), and transform them first into Core Scenario Model (CSM), and then into different performance models. The composition of the aspects with the primary (base) model is performed at the CSM level. A new formal definition of CSM properties and operations is described as a foundation for scenario-based weaving. The proposed approach is illustrated with an example that utilizes two standards, TPC-W and SSL. 相似文献
942.
Jun Cao Ayush Goyal Krista A. Novstrup Samuel P. Midkiff James M. Caruthers 《International journal of parallel programming》2009,37(2):127-152
Well designed domain specific languages have three important benefits: (1) the easy expression of problems, (2) the application
of domain specific optimizations (including parallelization), and (3) dramatic improvements in productivity for their users.
In this paper we describe a compiler and parallel runtime system for modeling the complex kinetics of rubber vulcanization
and olefin polymerization that achieves all of these goals. The compiler allows the development of a system of ordinary differential
equations describing a complex vulcanization reaction or single-site olefin polymerization reaction—a task that used to require
months—to be done in hours. A specialized common sub-expression elimination and other algebraic optimizations sufficiently
simplify the complex machine generated code to allow it to be compiled—eliminating all but 8.0% of the operations in our largest
program and enabling over 60 times faster execution on our largest benchmark codes. The parallel runtime and dynamic load
balancing scheme enables fast simulations of the model. 相似文献
943.
A particle is treated as a whole individual in all researches on particle swarm optimization (PSO) currently, these are not concerned with the information of every particle’s dimensional vector. A visual modeling method describing particle’s dimensional vector behavior is presented in this paper. Based on the analysis of visual modeling, the reason for premature convergence and diversity loss in PSO is explained, and a new modified algorithm is proposed to ensure the rational flight of every particle’s dimensional component. Meanwhile, two parameters of particle-distribution-degree and particle-dimension-distance are introduced into the proposed algorithm in order to avoid premature convergence. Simulation results of the new PSO algorithm show that it has a better ability of finding the global optimum, and still keeps a rapid convergence as with the standard PSO. 相似文献
944.
We present a probabilistic model of user affect designed to allow an intelligent agent to recognise multiple user emotions
during the interaction with an educational computer game. Our model is based on a probabilistic framework that deals with
the high level of uncertainty involved in recognizing a variety of user emotions by combining in a Dynamic Bayesian Network
information on both the causes and effects of emotional reactions. The part of the framework that reasons from causes to emotions
(diagnostic model) implements a theoretical model of affect, the OCC model, which accounts for how emotions are caused by one’s appraisal of
the current context in terms of one’s goals and preferences. The advantage of using the OCC model is that it provides an affective
agent with explicit information not only on which emotions a user feels but also why, thus increasing the agent’s capability to effectively respond to the users’ emotions. The challenge is that building the
model requires having mechanisms to assess user goals and how the environment fits them, a form of plan recognition. In this paper, we illustrate how we built the predictive part of the affective model by combining general theories with
empirical studies to adapt the theories to our target application domain. We then present results on the model’s accuracy,
showing that the model achieves good accuracy on several of the target emotions. We also discuss the model’s limitations,
to open the ground for the next stage of the work, i.e., complementing the model with diagnostic information.
相似文献
Heather MaclarenEmail: |
945.
A. J. Cuadros-Vargas M. Lizier R. Minghim L. G. Nonato 《Journal of Mathematical Imaging and Vision》2009,33(1):11-23
Techniques devoted to generating triangular meshes from intensity images either take as input a segmented image or generate
a mesh without distinguishing individual structures contained in the image. These facts may cause difficulties in using such
techniques in some applications, such as numerical simulations. In this work we reformulate a previously developed technique
for mesh generation from intensity images called Imesh. This reformulation makes Imesh more versatile due to an unified framework that allows an easy change of refinement metric, rendering it effective for constructing
meshes for applications with varied requirements, such as numerical simulation and image modeling. Furthermore, a deeper study
about the point insertion problem and the development of geometrical criterion for segmentation is also reported in this paper.
Meshes with theoretical guarantee of quality can also be obtained for each individual image structure as a post-processing
step, a characteristic not usually found in other methods. The tests demonstrate the flexibility and the effectiveness of
the approach.
相似文献
L. G. Nonato (Corresponding author)Email: |
946.
Cyril Montabert D. Scott McCrickard Woodrow W. Winchester Manuel A. Prez-Quiones 《Interacting with computers》2009,21(4):304-315
Many software systems fail to address their intended purpose because of a lack of user involvement and requirements deficiencies. This paper discusses the elaboration of a requirements-analysis process that integrates a critical-parameter-based approach to task modeling within a user-centric design framework. On one hand, adapting task models to capture requirements bridges the gap between scenarios and critical parameters which benefits design from the standpoint of user involvement and accurate requirements. On the other hand, using task models as a reusable component leverages requirements reuse which benefits design by increasing quality while simultaneously reducing development costs and time-to-market. First, we present the establishment of both a user-centric and reuse-centric requirements process along with its implementation within an integrated design tool suite. Secondly, we report the design, procedures, and findings of two user studies aimed at assessing the feasibility for novice designers to conduct the process as well as evaluating the resulting benefits upon requirements-analysis deliverables, requirements quality, and requirements reuse. 相似文献
947.
This paper proposes a fuzzy modeling method via Enhanced Objective Cluster Analysis to obtain the compact and robust approximate TSK fuzzy model. In our approach, the Objective Cluster Analysis algorithm is introduced. In order to obtain more compact and more robust fuzzy rule prototypes, this algorithm is enhanced by introducing the Relative Dissimilarity Measure and the new consistency criterion to represent the similarity degree between the clusters. By these additional criteria, the redundant clusters caused by iterations are avoided; the subjective influence from human judgment for clustering is weakened. Moreover the clustering results including the number of clusters and the cluster centers are considered as the initial condition of the premise parameters identification. Thus the traditional iteration modeling procedure for determining the number of rules and identifying parameters is changed into one-off modeling, which significantly reduces the burden of computation. Furthermore the decomposition errors and the approximation errors resulted from premise parameters identification by Fuzzy c-Means clustering are decreased. For the consequence parameters identification, the Stable Kalman Filter algorithm is adopted. The performance of the proposed modeling method is evaluated by the example of Box–Jenkins gas furnace. The simulation results demonstrate the power of our model. 相似文献
948.
基于OWL的软件工程数据建模 总被引:1,自引:0,他引:1
网络本体语言(Web ontology language,OWL)是语义网技术的一个重要组成部分,适合于对复杂的数据进行语义描述和建模.在软件系统的开发过程中通常会产生大量结构复杂、语义丰富的数据,而建立一个灵活的语义模型是对各类软件工程数据进行统一管理的基础.从设计和实现海量软件工程数据管理平台的需求出发,提出了一种基于OWL的软件工程数据描述模型.该模型不仅能够对源代码、需求、测试、版本和缺陷数据进行描述,同时还能对这些数据之问的语义关联进行描述.通过案例分析对模型的有效性进行了讨论. 相似文献
949.
950.