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51.
It has been argued that blogs, as an extension of 1960s 'New Journalism,' have become an important form of alternative media. At their idealized best, blogs can report news without the constraints of censure or the pressures of advertising. This argument suggests that blogs can therefore offer a deeper analysis, based upon a diverse range of sources and contributing citizen commentators, which is not possible through modern corporate, mainstream outlets. This exploratory study uses both critical discourse and content analysis to examine 344 posts, 1,712 hyperlinks, and 10,401 comments from 4 political/current events blogs within a 7-day period. This research argues that previous conceptualizations of alternative media, at least in relation to the political/current events blogosphere, might need reconsideration. 相似文献
52.
Minimum Setup Minimum Aberration Two‐level Split‐plot Type Designs for Physical Prototype Testing 下载免费PDF全文
Linda Lee Ho Carla A. Vivacqua André Luís Santos de Pinho 《Quality and Reliability Engineering International》2016,32(3):1007-1020
Although new technologies allow for less effort in prototyping, physical testing still remains an important step in the product development cycle. Well‐planned experiments are useful to guide the decision‐making process. During the design of an experiment, one of the challenges is to balance limited resources and system constraints to obtain useful information. It is common that prototypes are composed of several parts, with some parts more difficult to assemble than others. And, usually, there is only one piece available of each part type and a large number of different setups. Under these conditions, designs with randomization restrictions become attractive approaches. Considering this scenario, a new and additional criterion, minimum setup, to construct split‐plot type designs is presented. Designs with the minimum number of setups of the more difficult parts, which are especially useful for screening purposes in physical prototype testing, are discussed. The use of the proposed criterion combined with minimum aberration for selecting a regular design is shown through a real application in testing car prototypes. As a tool to practitioners, catalogs of selected 32‐run minimum setup minimum aberration split‐split‐plot and split‐split‐split‐plot designs are presented. More complete catalogs are available as Supporting information. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
53.
C. Melody Carswell Cindy H. Lio Martina I. Klein Duncan Clarke Stephen Strup 《Applied ergonomics》2010,42(1):138-145
Introduction
Subjective workload measures are usually administered in a visual-manual format, either electronically or by paper and pencil. However, vocal responses to spoken queries may sometimes be preferable, for example when experimental manipulations require continuous manual responding or when participants have certain sensory/motor impairments. In the present study, we evaluated the acceptability of the hands-free administration of two subjective workload questionnaires - the NASA Task Load Index (NASA-TLX) and the Multiple Resources Questionnaire (MRQ) - in a surgical training environment where manual responding is often constrained.Method
Sixty-four undergraduates performed fifteen 90-s trials of laparoscopic training tasks (five replications of 3 tasks - cannulation, ring transfer, and rope manipulation). Half of the participants provided workload ratings using a traditional paper-and-pencil version of the NASA-TLX and MRQ; the remainder used a vocal (hands-free) version of the questionnaires. A follow-up experiment extended the evaluation of the hands-free version to actual medical students in a Minimally Invasive Surgery (MIS) training facility.Results
The NASA-TLX was scored in 2 ways - (1) the traditional procedure using participant-specific weights to combine its 6 subscales, and (2) a simplified procedure - the NASA Raw Task Load Index (NASA-RTLX) - using the unweighted mean of the subscale scores. Comparison of the scores obtained from the hands-free and written administration conditions yielded coefficients of equivalence of r = 0.85 (NASA-TLX) and r = 0.81 (NASA-RTLX). Equivalence estimates for the individual subscales ranged from r = 0.78 (“mental demand”) to r = 0.31 (“effort”). Both administration formats and scoring methods were equally sensitive to task and repetition effects. For the MRQ, the coefficient of equivalence for the hands-free and written versions was r = 0.96 when tested on undergraduates. However, the sensitivity of the hands-free MRQ to task demands (ηpartial2 = 0.138) was substantially less than that for the written version (ηpartial2 = 0.252). This potential shortcoming of the hands-free MRQ did not seem to generalize to medical students who showed robust task effects when using the hands-free MRQ (ηpartial2 = 0.396). A detailed analysis of the MRQ subscales also revealed differences that may be attributable to a “spillover” effect in which participants’ judgments about the demands of completing the questionnaires contaminated their judgments about the primary surgical training tasks.Conclusion
Vocal versions of the NASA-TLX are acceptable alternatives to standard written formats when researchers wish to obtain global workload estimates. However, care should be used when interpreting the individual subscales if the object is to make comparisons between studies or conditions that use different administration modalities. For the MRQ, the vocal version was less sensitive to experimental manipulations than its written counterpart; however, when medical students rather than undergraduates used the vocal version, the instrument’s sensitivity increased well beyond that obtained with any other combination of administration modality and instrument in this study. Thus, the vocal version of the MRQ may be an acceptable workload assessment technique for selected populations, and it may even be a suitable substitute for the NASA-TLX. 相似文献54.
55.
Virtual teams (VTs) are teams whose members do not share a common workspace all of the time, and must therefore collaborate using communication and collaboration tools such as email, videoconferencing, etc. Although the body of research on VTs is quickly expanding, to date, the field has yet to produce a comprehensive and coherent foundation upon which future research can be based, and empirical findings based on a substantive sample of real VTs remain limited at this time. This study fills a void in the VT literature with respect to defining and operationalizing the construct of degree of virtuality, and responds to calls for research that studies ongoing VTs, under real conditions. Data were collected from 30 VTs working in a Canadian technology‐based organization. Degree of virtuality was defined to include three dimensions: the proportion of work time that the VT members spend working apart (team time worked virtually), the proportion of the team's members who work virtually (member virtuality) and the degree of separation of the team's members (distance virtuality). The VTs in this study were found to have varying degrees of virtuality, and although the three dimensions were not highly intercorrelated, all were found to be significantly correlated to variables that have been previously linked to VT effectiveness. The correlations were all in the expected direction (negative), indicating that higher degrees of virtuality are associated with perceived decreases in the quality of team interactions and performance. The results of this research would suggest that the more that teams move away from the proximate form, the more the traditional measures of team effectiveness are negatively impacted. 相似文献
56.
Linda A. Jackson Alexander von EyeHiram E. Fitzgerald Edward A. WittYong Zhao 《Computers in human behavior》2011,27(1):599-604
In this research we examined the prediction of children’s body mass index (BMI), body weight, academic performance, social self-esteem and overall self-esteem from their IT (information technology) use, specifically, their Internet use, cell phone use and videogame playing, after controlling for the effects of gender, race, age and household income on these measures. Participants were 482 children whose average age was 12 years old. One-third was African American and two-thirds were Caucasian American. Results indicated that IT use did not predict BMI or body weight, contrary to one previous survey and the widespread belief that screen time is responsible for the obesity epidemic among our nation’s children. Instead, BMI and body weight were higher for African Americans, older children and children from lower income households. The sole and strong positive predictor of visual-spatial skills was videogame playing, which also predicted lower grade point averages (GPAs). Gender and Internet use predicted standardized test scores in reading skills. Females and children who used the Internet more had better reading skills than did males and children who used the Internet less, respectively. Implications of these findings for future research on the benefits and liabilities of IT use are discussed. 相似文献
57.
The objective of the current research is to model trends in video game playing, overall computer use, and communication technology use in a longitudinal sample of youths, aged 11-16 over a 3-year interval. In addition, individual difference characteristics that may be predictive of these trends were included, namely, socio-demographic characteristics (gender, ethnicity, and parental income) and personality characteristics (self-esteem, the Big Five personality factors). Findings suggested that youth increased their overall computer and communication technology use but decreased their videogame playing over time. Many individual differences predicted mean levels of these technologies with fewer predicting slopes. Conclusions, implications, and limitations are discussed. 相似文献
58.
Linda A. Jackson Alexander von EyeEdward A. Witt Yong ZhaoHiram E. Fitzgerald 《Computers in human behavior》2011,27(1):228-239
In this research we examined the effects of Internet use and videogame playing on children’s academic performance. Gender, race, and income were also considered. Participants were 482 youth, average age 12 years old. One-third were African American and two-thirds were Caucasian American. All measures were completed twice, first in Year 1 and then one year later, Year 2. Results indicated that greater Internet use was associated with better reading skills, but only for youth initially low in reading skills. Videogame playing was associated with better visual-spatial skill but also with lower GPAs. Gender, race and income influenced Internet use, videogame playing and academic performance but not the relationships between using these technologies and academic performance. Implications of the results for increasing the benefits of technology use are discussed. 相似文献
59.
60.
Although function points (FP) are considered superior to source lines of code (SLOC) for estimating software size and monitoring developer productivity, practitioners still commonly use SLOC. One reason for this is that individuals who fill different roles on a development team, such as managers and developers, may perceive the benefits of FP differently. We conducted a survey to determine whether a perception gap exists between managers and developers for FP and SLOC across several desirable properties of software measures. Results suggest managers and developers perceive the benefits of FP differently and indicate that developers better understand the benefits of using FP than managers. 相似文献