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141.
Cross-lagged analysis of panel survey data collected from Taiwanese college students (initially 387 males and 370 females) was used to examine the temporal relationship between problematic Internet use (PIU) and lifestyle changes during the first year in college. We hypothesized that a reciprocal relationship might exist between PIU and lifestyle changes. Structural equation modeling was adopted to test several nested cross-lagged relationship models. The results showed that four measures of lifestyle changes and PIU were moderately to highly stable across one year. Moreover, PIU in freshman year predicted negative changes in lifestyle in the following year, including a reduction of physical and social activities, irregular diet and unhealthy sleep. Lifestyle changes in freshman year, in contrast, did not predict PIU in sophomore year; the hypothesized reciprocal relationship between PIU and lifestyle changes was not warranted. Implications and limitations are discussed.  相似文献   
142.
Abstract

To evaluate ubiquitous computing technologies, which may be embedded in the environment, embedded in objects, worn, or carried by the user throughout everyday life, it is essential to use methods that accommodate the often unpredictable, real-world environments in which the technologies are used. This article discusses how we have adapted and applied traditional methods from psychology and human-computer interaction, such as Wizard of Oz and Experience Sampling, to be more amenable to the in situ evaluations of ubiquitous computing applications, particularly in the early stages of design. The way that ubiquitous computing technologies can facilitate the in situ collection of self-report data is also discussed. Although the focus is on ubiquitous computing applications and tools for their assessment, it is believed that the in situ evaluation tools that are proposed will be generally useful for field trials of other technology, applications, or formative studies that are concerned with collecting data in situ.  相似文献   
143.
Sunny 《程序员》2005,(8):75-77
近几年国内的游戏公司如雨后春笋般层出不穷,而相应游戏制作人材也变得紧缺,看着国内游戏业的成长,小编感到十分欣慰,但游戏编程这一职业想进入这个圈子的有志之士来说似乎显得有些高不可攀,相比之下游戏策划这一职业则显得门坎比较低。其实不然,一名游戏策划不仅要有源源不断的灵感创意,以及对各种游戏丰富的认知,还要对地理、历史、人文等综合知识有一定的了解。前几天小编听朋友说最近网上正流传着一些游戏公司的面试及笔试题,于是特意搜集整理了部分试题,并请圈里的朋友帮忙作答(在此感谢天下第七、邓猫儿帮助解答)。其中的答案很多都是见仁见智的,希望能给想做游戏策划的朋友一些参考。  相似文献   
144.
Sunny 《程序员》2005,(8):78-80
关卡是游戏设计中不可缺少的元素,无论你要制作的游戏是什么类型,或多或少都会包含一些相应的关卡。说起关卡设计,最典型的要属解谜(PUZZLE)类和角色扮演类(RPG)游戏,下面笔者就以RPG游戏为例,为大家简单介绍一下游戏关卡设计中的一些概念和窍门。  相似文献   
145.
Software systems accumulate technical debt (TD) when short-term goals in software development are traded for long-term goals (e.g., quick-and-dirty implementation to reach a release date versus a well-refactored implementation that supports the long-term health of the project). Some forms of TD accumulate over time in the form of source code that is difficult to work with and exhibits a variety of anomalies. A number of source code analysis techniques and tools have been proposed to potentially identify the code-level debt accumulated in a system. What has not yet been studied is if using multiple tools to detect TD can lead to benefits, that is, if different tools will flag the same or different source code components. Further, these techniques also lack investigation into the symptoms of TD “interest” that they lead to. To address this latter question, we also investigated whether TD, as identified by the source code analysis techniques, correlates with interest payments in the form of increased defect- and change-proneness. Comparing the results of different TD identification approaches to understand their commonalities and differences and to evaluate their relationship to indicators of future TD “interest.” We selected four different TD identification techniques (code smells, automatic static analysis issues, grime buildup, and Modularity violations) and applied them to 13 versions of the Apache Hadoop open source software project. We collected and aggregated statistical measures to investigate whether the different techniques identified TD indicators in the same or different classes and whether those classes in turn exhibited high interest (in the form of a large number of defects and higher change-proneness). The outputs of the four approaches have very little overlap and are therefore pointing to different problems in the source code. Dispersed Coupling and Modularity violations were co-located in classes with higher defect-proneness. We also observed a strong relationship between Modularity violations and change-proneness. Our main contribution is an initial overview of the TD landscape, showing that different TD techniques are loosely coupled and therefore indicate problems in different locations of the source code. Moreover, our proxy interest indicators (change- and defect-proneness) correlate with only a small subset of TD indicators.  相似文献   
146.
Sethi S  Ge L  Ci L  Ajayan PM  Dhinojwala A 《Nano letters》2008,8(3):822-825
The design of reversible adhesives requires both stickiness and the ability to remain clean from dust and other contaminants. Inspired by gecko feet, we demonstrate the self-cleaning ability of carbon nanotube-based flexible gecko tapes.  相似文献   
147.
The thematic area studied in this paper considers environmental issues such as atmospheric pollution from the combustion of fossil fuels, and the environmental impacts from the generation of urban agricultural solid wastes. This study has estimated the potential for hydrogen and biogas production from solid urban waste (SUW) and wine waste from Bento Gonçalves, which is a region in Brazil with the largest wine throughput and subsequent waste generation, thus providing a potential high-energy feedstock. The resulting hydrogen and biogas are assumed to displace the existing fuels in the local bus fleet. The analytical work consisted of three scenarios - scenario 1: production of biogas using SUW, sourced exclusively from the municipality of Bento Gonçalves; Scenario 2: the possibility to supply SUW from Bento Gonçalves and surrounding cities, to produce biogas; Scenario 3: the possibility to use wine waste and SUW for biogas production. Scenario 3 showed the greatest energy yield with 37.9 Gg of biomethane produced per year, which can supply the entire public bus fleet of Bento Gonçalves. The resulting hydrogen production potential using steam reforming of biomethane is 1.09 E+08 Nm3H2.d?1 which can generate 2.62 TW h.year?1 of electrical energy, avoiding approximate emissions of 355 ktonCO2.year?1. These findings indicate value in the production of biogas from urban and agricultural wastes, especially for the generation of methane, hydrogen and useful energy outputs. Its production from renewable and clean sources contributes to the gradual transformation of an economy currently dependent on non-renewable resources into a circular and renewable economy.  相似文献   
148.
Computational Economics - Communication is a natural activity to gain information and exchange ideas for making proper economic decisions. The mechanism of social interaction remains inadequately...  相似文献   
149.
Journal of Materials Science - Reactive molecular additives have often been employed to tailor the mechanical properties of epoxy resins. In addition, several studies have reported improved...  相似文献   
150.
This study aimed to evaluate the effects of β2-adrenergic receptor (ADRB2) gene polymorphisms on ritodrine therapy outcomes in patients with preterm labor. Genotyping analysis of ADRB2 gene (rs1042713, rs1042714, rs1042717, rs1042718, and rs1042719) was performed on 137 patients with preterm labor. Survival analysis was conducted for the effects of SNPs on the median time to delivery as a primary outcome. The median time to delivery in the study patients was 349.3 h. Gestational age at admission and modified Bishop scores revealed significant effects on time to delivery (p < 0.001). Among studied SNPs, rs1042717 and rs1042718 showed linkage disequilibrium in this population, and their effects on time to delivery were marginally significant (p < 0.1). Patients with variant-homozygotes in the rs1042713 showed considerably shortened time to delivery compared to wild-allele carriers. The rs1042719 polymorphism significantly affected time to delivery in both univariate and multivariate analysis; the GC and CC carriers showed 64% decrease in time to delivery compared to the wild-type homozygote carriers. Based on the results, it was concluded that the gene polymorphisms of ADRB2 could affect ritodrine therapy in patients with preterm labor. However, given the single-center and the relatively small sample size, our hypothesis requires further independent validation using multi-center and large sample size.  相似文献   
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