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991.
《Behaviour & Information Technology》2012,31(2):261-271
The vocational schools in Taiwan regard professional certifications as a badge of skills achievement. The teaching in this context usually focuses on how to help students enhance their professional skills and pass the certificate examinations, particularly for computing courses. However, due to national education policy, pure online courses are not permitted here and in some other nations. In order to provide an appropriate design and arrangement of blended learning (BL) courses, the authors redesigned a course, integrating web-enabled self-regulated learning (SRL) with variations in online class frequency, and explored their effects on enhancing students' skills of deploying database management system (DBMS) and their thoughts regarding blended course and interventions concerning SRL. Three class sections with a total of 112 students were taken as three distinct groups. The results indicated that students in the group of SRL and BL with five online classes had the highest grades for using DBMS among the three groups, and had very positive thoughts regarding the interventions concerning BL and SRL. The authors also provide suggestions and implications for teachers and schools to adopt innovative teaching methods and technologies, and redesign their courses to help students learn. 相似文献
992.
《Behaviour & Information Technology》2012,31(3):277-285
Today, software piracy is an issue of global importance. Computer science students are the future information and communication technologies professionals and it is important to study the way they approach this issue. In this article, we attempt to study attitudes, behaviours and the corresponding reasoning of computer science students in Greece regarding software piracy. The statements taken in 56 semi-structured interviews with students indicate that computer science students in Greece make intensive use of pirated software, mention as main reason for their practice the cost of genuine software, and blame the academic environment, coincidental stereotypes and their student status for this behaviour. They acknowledge the immoral character of their actions, as well as the fact that others are affected by software piracy, but they pay little attention to this action and they practically don't care. While keeping distance from software development companies, when specifically asked, they easily adopt the role of a software developer and attempt to substantiate their current and eventually future attitude out of hand. They consider software copyright laws to be inapplicable and unrealistic and fail to argue against intellectual property rights for mere digital products, such as software. 相似文献
993.
Software modernization is critical for organizations that need cost-effective solutions to deal with the rapid obsolescence of software and the increasing demand for new functionality. This paper presents the XIRUP modernization methodology, which proposes a highly iterative process, structured into four phases: preliminary evaluation, understanding, building and migration. This modernization process is feature-driven, component-based, focused on the early elicitation of key information, and relies on a model-driven approach with extensive use of experience from the previous projects. XIRUP has been defined in the European IST project MOMOCS, which has also built a suite of support tools. This paper introduces the process using a case study that illustrates its activities, related tools and results. The discussion highlights the specific characteristics of modernization projects and how a customized methodology can take advantage of them. 相似文献
994.
Fault prediction and the discriminative powers of connectivity-based object-oriented class cohesion metrics 总被引:1,自引:0,他引:1
Jehad Al Dallal 《Information and Software Technology》2012,54(4):396-416
Context
Several metrics have been proposed to measure the extent to which class members are related. Connectivity-based class cohesion metrics measure the degree of connectivity among the class members.Objective
We propose a new class cohesion metric that has higher discriminative power than any of the existing cohesion metrics. In addition, we empirically compare the connectivity and non-connectivity-based cohesion metrics.Method
The proposed class cohesion metric is based on counting the number of possible paths in a graph that represents the connectivity pattern of the class members. We theoretically and empirically validate this path connectivity class cohesion (PCCC) metric. The empirical validation compares seven connectivity-based metrics, including PCCC, and 11 non-connectivity-based metrics in terms of discriminative and fault detection powers. The discriminative-power study explores the probability that a cohesion metric will incorrectly determine classes to be cohesively equal when they have different connectivity patterns. The fault detection study investigates whether connectivity-based metrics, including PCCC, better explain the presence of faults from a statistical standpoint in comparison to other non-connectivity-based cohesion metrics, considered individually or in combination.Results
The theoretical validation demonstrates that PCCC satisfies the key cohesion properties. The results of the empirical studies indicate that, in contrast to other connectivity-based cohesion metrics, PCCC is much better than any comparable cohesion metric in terms of its discriminative power. In addition, the results also indicate that PCCC measures cohesion aspects that are not captured by other metrics, wherein it is considerably better than other connectivity-based metrics but slightly worse than some other non-connectivity-based cohesion metrics in terms of its ability to predict faulty classes.Conclusion
PCCC is more useful in practice for the applications in which practitioners need to distinguish between the quality of different classes or the quality of different implementations of the same class. 相似文献995.
T.H. Ng 《Information and Software Technology》2012,54(1):99-118
Context
Practitioners may use design patterns to organize program code. Various empirical studies have investigated the effects of pattern deployment and work experience on the effectiveness and efficiency of program maintenance. However, results from these studies are not all consistent. Moreover, these studies have not considered some interesting factors, such as a maintainer’s prior exposure to the program under maintenance.Objective
This paper aims at identifying what factors may contribute to the productivity of maintainers in the context of making correct software changes when they work on programs with deployed design patterns.Method
We performed an empirical study involving 118 human subjects with three change tasks on a medium-sized program to explore the possible effects of a suite of six human and program factors on the productivity of maintainers, measured by the time taken to produce a correctly revised program in a course-based setting. The factors we studied include the deployment of design patterns and the presence of pattern-unaware solutions, as well as the maintainer’s prior exposure to design patterns, the subject program and the programming language, and prior work experience.Results
Among the factors under examination, we find that the deployment of design patterns, prior exposure to the program and the presence of pattern-unaware solutions are strongly correlated with the time taken to correctly complete maintenance tasks. We also report some interesting observations from the experiment.Conclusion
A new factor, namely, the presence of pattern-unaware solutions, contributes to the efficient completion of maintenance tasks of programs with deployed design patterns. Moreover, we conclude from the study that neither prior exposure to design patterns nor prior exposure to the programming language is supported by sufficient evidences to be significant factors, whereas the subjects’ exposure to the program under maintenance is notably more important. 相似文献996.
997.
作为现代三大统计方法之一的聚类分析法目前已经广泛的应用于经济、生物、地理等领域。将聚类分析方法应用于大庆师范学院数学科学学院07级数学与应用数学专业本科2班全体学生的所有所学科目的成绩中,利用SPSSl6.0统计软件对学生进行分类,结合教育科学知识和多元统计的相关理论,分析了不同类型学生的特点并提出相应的培养意见,为高校有针对性的培养学生提供了一定依据。 相似文献
998.
研究了响应面法在聚氯乙烯(PVC)热稳定剂配方研究中的使用价值.依据Box-Benhnken的中心组合实验设计原理,设计了响应面分析中的3因素3水平分析表及热稳定实验方案.使用SAS软件对实验数据进行了处理,得到了硬脂酸锌、硬脂酸钙和硬脂酸钡之间相互作用对热稳定时间影响的响应面曲面图.分析图表可知,硬脂酸锌对热稳定时间产生了负作用,硬脂酸锌和硬脂酸钙之间及硬脂酸锌与硬脂酸钡之间产生了交互作用. 相似文献
999.
黄碧玲 《杭州电子科技大学学报》2012,32(5):191-194
风险管理在软件质量管理体系中有着非常重要的作用.风险的起因来自于软件项目和产品研发过程中的不确定性,而这种不确定性就很可能给整个软件产品的质量带来各种各样的隐患.通过在软件测试过程中进行风险识别、风险分析和风险控制,从而进一步提高软件质量.该文从3个方面对软件测试风险管理进行阐述,并对软件测试常见风险进行分析,提出应对措施. 相似文献
1000.
介绍了Mathematica软件中二元函数图形绘制的基本方法,进而研究了曲面相交所围成的空间立体图形的绘制方法和技巧,利用Mathematica软件绘制出了牟合方盖、球面与圆柱面相交、马鞍面与平面相交的立体图形. 相似文献