全文获取类型
收费全文 | 1464篇 |
免费 | 8篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 123篇 |
金属工艺 | 17篇 |
机械仪表 | 20篇 |
建筑科学 | 13篇 |
矿业工程 | 2篇 |
能源动力 | 7篇 |
轻工业 | 64篇 |
水利工程 | 1篇 |
石油天然气 | 6篇 |
武器工业 | 1篇 |
无线电 | 63篇 |
一般工业技术 | 96篇 |
冶金工业 | 990篇 |
原子能技术 | 6篇 |
自动化技术 | 59篇 |
出版年
2021年 | 4篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2016年 | 7篇 |
2015年 | 4篇 |
2014年 | 11篇 |
2013年 | 29篇 |
2012年 | 12篇 |
2011年 | 19篇 |
2010年 | 13篇 |
2009年 | 16篇 |
2008年 | 20篇 |
2007年 | 15篇 |
2006年 | 21篇 |
2005年 | 20篇 |
2004年 | 16篇 |
2003年 | 19篇 |
2002年 | 15篇 |
2001年 | 18篇 |
2000年 | 15篇 |
1999年 | 34篇 |
1998年 | 272篇 |
1997年 | 171篇 |
1996年 | 109篇 |
1995年 | 66篇 |
1994年 | 55篇 |
1993年 | 53篇 |
1992年 | 17篇 |
1991年 | 18篇 |
1990年 | 25篇 |
1989年 | 29篇 |
1988年 | 30篇 |
1987年 | 25篇 |
1986年 | 20篇 |
1985年 | 14篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1982年 | 15篇 |
1981年 | 14篇 |
1980年 | 16篇 |
1978年 | 9篇 |
1977年 | 46篇 |
1976年 | 64篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1973年 | 6篇 |
1972年 | 9篇 |
1971年 | 4篇 |
1968年 | 5篇 |
1955年 | 7篇 |
排序方式: 共有1472条查询结果,搜索用时 15 毫秒
41.
Several vendors and consortia have independently developed standards that define the basic mechanics for building and interconnecting software components. Sun's JavaBeans has emerged as the leading rival to Microsoft's DCOM, supplanting the OpenDoc standard from the now defunct Component Integration Laboratories. Component software is moving from its original focus on desktop-bound compound documents to enterprise applications that include distributed server components. The backers of competing standards are racing to capture market leadership by delivering the tangible benefits of component standards via distributed component platforms-integrated development and runtime environments that isolate much of the conceptual and technical complexity involved in building component-based applications. With DCPs, businesses can assign their few highly skilled programmers to component construction and use less sophisticated developers to carry out the simpler assembly tasks. By making component standards available to the broadest possible spectrum of developers, DCPs essentially drive those standards to market. This article reviews the state of component software as embodied in DCPs. The two DCP market leaders are Microsoft's DCOM (or ActiveX/DCOM) and Sun's JavaBeans. However, Internet and OMG component standards are emerging that will likely impact both the content and status of these two DCPs. The article also discusses component frameworks, which extend DCPs to provide more complete application development solutions 相似文献
42.
Robust and Rapid Generation of Animated Faces from Video Images: A Model-Based Modeling Approach 总被引:1,自引:0,他引:1
Zhengyou Zhang Zicheng Liu Dennis Adler Michael F. Cohen Erik Hanson Ying Shan 《International Journal of Computer Vision》2004,58(2):93-119
We have developed an easy-to-use and cost-effective system to construct textured 3D animated face models from videos with minimal user interaction. This is a particularly challenging task for faces due to a lack of prominent textures. We develop a robust system by following a model-based approach: we make full use of generic knowledge of faces in head motion determination, head tracking, model fitting, and multiple-view bundle adjustment. Our system first takes, with an ordinary video camera, images of a face of a person sitting in front of the camera turning their head from one side to the other. After five manual clicks on two images to indicate the position of the eye corners, nose tip and mouth corners, the system automatically generates a realistic looking 3D human head model that can be animated immediately (different poses, facial expressions and talking). A user, with a PC and a video camera, can use our system to generate his/her face model in a few minutes. The face model can then be imported in his/her favorite game, and the user sees themselves and their friends take part in the game they are playing. We have demonstrated the system on a laptop computer live at many events, and constructed face models for hundreds of people. It works robustly under various environment settings. 相似文献
43.
David W. Eby Nina M. Silverstein Lisa J. Molnar David LeBlanc Geri Adler 《Accident; analysis and prevention》2012
According to the Alzheimer's Association (2011), (1) in 8 people age 65 and older, and about one-half of people age 85 and older, have Alzheimer's disease in the United States (US). There is evidence that drivers with Alzheimer's disease and related dementias are at an increased risk for unsafe driving. Recent advances in sensor, computer, and telecommunication technologies provide a method for automatically collecting detailed, objective information about the driving performance of drivers, including those with early stage dementia. The objective of this project was to use in-vehicle technology to describe a set of driving behaviors that may be common in individuals with early stage dementia (i.e., a diagnosis of memory loss) and compare these behaviors to a group of drivers without cognitive impairment. Seventeen drivers with a diagnosis of early stage dementia, who had completed a comprehensive driving assessment and were cleared to drive, participated in the study. Participants had their vehicles instrumented with a suite of sensors and a data acquisition system, and drove 1–2 months as they would under normal circumstances. Data from the in-vehicle instrumentation were reduced and analyzed, using a set of algorithms/heuristics developed by the research team. Data from the early stage dementia group were compared to similar data from an existing dataset of 26 older drivers without dementia. The early stage dementia group was found to have significantly restricted driving space relative to the comparison group. At the same time, the early stage dementia group (which had been previously cleared by an occupational therapist as safe to drive) drove as safely as the comparison group. Few safety-related behavioral errors were found for either group. Wayfinding problems were rare among both groups, but the early stage dementia group was significantly more likely to get lost. 相似文献
44.
Confirmation of the Dominant Defect Mechanism in Amorphous In–Zn–O Through the Application of In Situ Brouwer Analysis 下载免费PDF全文
Stephanie L. Moffitt Alexander U. Adler Thomas Gennett David S. Ginley John D. Perkins Thomas O. Mason 《Journal of the American Ceramic Society》2015,98(7):2099-2103
The dominant point defect mechanism of amorphous (a‐) indium zinc oxide (IZO) was probed through in situ electrical characterization of sputtered a‐IZO thin films in response to changes in oxygen partial pressure (pO) at 300C. The results yielded a power law dependence of conductivity (σ) versus pO of ~?1/6. This experimental method, known as Brouwer analysis, confirms doubly‐charged oxygen vacancies as the dominant defect species in a‐IZO. The success of this study suggests that Brouwer analysis is a viable method for studying the defect mechanisms of amorphous oxides. 相似文献
45.
46.
An emulsion-type product was prepared to determine the effect of irradiation on lipid and cholesterol oxidation, color change, and volatile production in raw pork with different fat contents. Lipid oxidation increased with an increase in fat content or irradiation dose. Irradiated batters had higher cholesterol oxides than nonirradiated, and the major cholesterol oxides formed in irradiated pork batters were 7α- and 7β-hydroxycholesterol. Hunter color a- and b-values of raw pork batters were decreased by irradiation regardless of fat content. Irradiation increased the amount ofvolatiles significantly. Although lipid oxidation of high fat products (10 and 15% fat) was higher than that of low fat products (4%), high fat products did not always produce greater amount of volatiles. In summary, irradiation increased lipid and cholesterol oxidation, volatiles production and had detrimental effects on the color of raw pork batters under aerobic condition. 相似文献
47.
48.
Wright Kathleen M.; Cabrera Oscar A.; Bliese Paul D.; Adler Amy B.; Hoge Charles W.; Castro Carl A. 《Canadian Metallurgical Quarterly》2009,6(2):108
The present study examined the effects of leadership and unit cohesion on mental health stigma and perceived barriers to care. A sample of 680 soldiers from combat support units were surveyed 3 months after their return from combat operations in Iraq. The survey included scales on psychological symptoms and perceptions of leader behaviors and unit cohesion, as well as items assessing stigma and barriers to care. The sample was used to test the independent and interactive effects of leadership and unit cohesion on soldiers’ perceptions of stigma and barriers to care. Analyses yielded significant interaction effects between leadership and cohesion in predicting stigma and barriers to care, while controlling for the effects of mental health symptoms. Soldiers who rated their leaders more highly and who reported higher unit cohesion also reported lower scores on both stigma and perceived barriers to care. Thus, positive leadership and unit cohesion can reduce perceptions of stigma and barriers to care, even after accounting for the relationship between mental health symptoms and these outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Adler Amy B.; Bliese Paul D.; McGurk Dennis; Hoge Charles W.; Castro Carl Andrew 《Canadian Metallurgical Quarterly》2009,77(5):928
Researchers have found that there is an increase in mental heath problems as a result of military-related traumatic events, and such problems increase in the months following return from combat. Nevertheless, researchers have not assessed the impact of early intervention efforts with this at-risk population. In the present study, the authors compared different early interventions with 2,297 U.S. soldiers following a year-long deployment to Iraq. Platoons were randomly assigned to standard postdeployment stress education, Battlemind debriefing, and small and large group Battlemind training. Results from a 4-month follow-up with 1,060 participants showed those with high levels of combat exposure who received Battlemind debriefing reported fewer posttraumatic stress symptoms, depression symptoms, and sleep problems than those in stress education. Small group Battlemind training participants with high combat exposure reported fewer posttraumatic stress symptoms and sleep problems than stress education participants. Compared to stress education participants, large group Battlemind training participants with high combat exposure reported fewer posttraumatic stress symptoms and lower levels of stigma and, regardless of combat exposure, reported fewer depression symptoms. Findings demonstrate that brief early interventions have the potential to be effective with at-risk occupational groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
There is growing concern in the United States about avoidable, unjust differences in health associated with sociodemographic characteristics, such as socioeconomic status and race/ethnicity. This concern has sparked research to identify how disparities develop and how they can be reduced. Studies showing that disparities occur at all levels of socioeconomic status, not simply at the very bottom, suggest that psychosocial factors play an important role. The author discusses both content and process issues in psychological research on disparities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献