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1.
面向对象的黑河下游河岸林植被覆盖信息分类!   总被引:1,自引:0,他引:1  
地表植被覆盖是描述区域生态系统的基础数据,也是全球及区域陆面过程、生态与水文众多模型中所需的重要地表参数。对于黑河下游额济纳绿洲,以Landsat 30m分辨率为主的遥感影像难以真实提取下游绿洲河岸林植被覆盖信息,而高分辨率影像目标地物轮廓清晰、空间细节信息丰富,有利于干旱背景下景观破碎、异质性强的植被覆盖信息分类。基于黑河下游额济纳绿洲QuickBird影像,通过面向对象的分类方法提取耕地、胡杨、柽柳、草地和裸地等主要植被覆盖类型,分类总体精度和Kappa系数分别为84.71%和0.7986。结果表明:利用面向对象分类方法对高分辨率影像进行植被覆盖信息分类,分类结果较好,能够满足精度要求。  相似文献   
2.
利用高分辨率遥感影像对森林资源进行大比例尺动态监测可以有效提高林业部门对森林资源管理的时效性。以福州市平潭岛为研究区域,利用高分辨率的WorldView\|2遥感影像,结合大比例尺森林小班矢量图层,基于面向对象的分类思想,采用分层监督分类的方法,提取森林资源变化图斑,实现大比例尺森林资源的动态监测。此种方法有效利用了原始小班边界,快速提取了变化区域,总体分类精度达到了90.85%,表明利用该方法进行大比例尺森林资源变化区域提取是有效可行的。  相似文献   
3.
为满足工业现场中对多种不同类型仪表进行集中监视、统一控制要求,设计一种多测试仪表数据采集与控制系统,该系统基于TCP/IP协议进行通信,使用VC进行编程,采用select模型、多线程技术以及扫描技术,实现对多种不同类型的测试仪表的动态接入和并发控制,并介绍一种面向对象的设计方案,以实现对多种不同类型仪表的兼容。  相似文献   
4.
In recent years, processor technology has evolved towards multicore processors, which include multiple processing units (cores) in a single package. Those cores, having their own private caches, often share a higher level cache memory dedicated to each processor die. This multi-level cache hierarchy in multicore processors raises the importance of cache utilization problem. Assigning parallel-running software components with common data to processor cores that do not share a common cache increases the number of cache misses. In this paper we present a novel approach that uses model-based information to guide the OS scheduler in assigning appropriate core affinities to software objects at run-time. We build graph models of software and cache hierarchies of processors and devise a graph matcher algorithm that provides mapping between these two graphs. Using this mapping we obtain candidate core sets that each software object can be affiliated with at run-time. These affiliations are determined based on the idea that software components that have the potential to share common data at run-time should run on cores that share a common cache. We also develop an object dispatcher algorithm that keeps track of object affiliations at run-time and dispatches objects by using the information from the compile-time graph matcher. We apply our approach on design pattern implementations and two different application program running on servers using CFS scheduling. Our results show that cache-aware dispatching based on information obtained from software model, decreases number of cache misses significantly and improves CFS’ scheduling performance.  相似文献   
5.
为了建立支撑汽车研发的数据库平台,在分析汽车工程数据特点基础上,提出一种数据库结构设计方法。该方法借鉴部分面向对象思想,首先对技术指标体系进行抽象及划分,然后配置对象模型,最后实例化产生实体。基于此思路设计数据库表结构模型,并在汽车工程数据库建设项目中使用该模型作为基础架构。应用情况表明该模型能够有效地描述工程数据,并能满足扩展需求。  相似文献   
6.
In this work, we present a simultaneous untangling and smoothing technique for quadrilateral and hexahedral meshes. The algorithm iteratively improves a quadrilateral or hexahedral mesh by minimizing an objective function defined in terms of a regularized algebraic distortion measure of the elements. We propose several techniques to improve the robustness and the computational efficiency of the optimization algorithm. In addition, we have adopted an object-oriented paradigm to create a common framework to smooth meshes composed by any type of elements, and using different minimization techniques. Finally, we present several examples to show that the proposed technique obtains valid meshes composed by high-quality quadrilaterals and hexahedra, even when the initial meshes contain a large number of tangled elements.  相似文献   
7.
BackgroundSource code size in terms of SLOC (source lines of code) is the input of many parametric software effort estimation models. However, it is unavailable at the early phase of software development.ObjectiveWe investigate the accuracy of early SLOC estimation approaches for an object-oriented system using the information collected from its UML class diagram available at the early software development phase.MethodWe use different modeling techniques to build the prediction models for investigating the accuracy of six types of metrics to estimate SLOC. The used techniques include linear models, non-linear models, rule/tree-based models, and instance-based models. The investigated metrics are class diagram metrics, predictive object points, object-oriented project size metric, fast&&serious class points, objective class points, and object-oriented function points.ResultsBased on 100 open-source Java systems, we find that the prediction model built using object-oriented project size metric and ordinary least square regression with a logarithmic transformation achieves the highest accuracy (mean MMRE = 0.19 and mean Pred(25) = 0.74).ConclusionWe should use object-oriented project size metric and ordinary least square regression with a logarithmic transformation to build a simple, accurate, and comprehensible SLOC estimation model.  相似文献   
8.
9.
Neurofuzzy networks are hybrid systems that combine neural networks with fuzzy systems, and the Adaptive Neuro-Fuzzy inference system (ANFIS) is a particular case in which a fuzzy system is implemented in the framework of an adaptive neural network. This neurofuzzy approach represents an effective structure to the modeling of plant dynamics, and the oriented-object programming environments offer an intuitive way to address this task. In this paper the MODELICA object-oriented environment has been applied to the ANFIS modeling and indirect control of the heavy and light product composition in a binary methanol-water distillation column by using the adaptive Levenberg–Marquardt approach. The results obtained demonstrate the potential of the adaptive ANFIS scheme under MODELICA for the dual control of composition both for changes in set points with null stationary error even when disturbances are present.  相似文献   
10.
实现了一个基于Web的原型决策支持系统。该系统依据以往天气条件的记录,递归地构建一个决策树,用其预测未来网球比赛能否举行。详细展示了一个原型决策支持系统开发周期,包括从分析、设计到实现,如何使用面向对象技术来开发系统。  相似文献   
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