全文获取类型
收费全文 | 231篇 |
免费 | 5篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 20篇 |
金属工艺 | 6篇 |
机械仪表 | 2篇 |
建筑科学 | 11篇 |
矿业工程 | 3篇 |
能源动力 | 6篇 |
轻工业 | 35篇 |
水利工程 | 4篇 |
石油天然气 | 1篇 |
无线电 | 9篇 |
一般工业技术 | 15篇 |
冶金工业 | 47篇 |
原子能技术 | 1篇 |
自动化技术 | 73篇 |
出版年
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 6篇 |
2014年 | 1篇 |
2013年 | 14篇 |
2012年 | 9篇 |
2011年 | 9篇 |
2010年 | 11篇 |
2009年 | 19篇 |
2008年 | 10篇 |
2007年 | 9篇 |
2006年 | 9篇 |
2005年 | 9篇 |
2004年 | 11篇 |
2003年 | 6篇 |
2002年 | 11篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 7篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 8篇 |
1992年 | 5篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 4篇 |
1977年 | 2篇 |
1976年 | 6篇 |
1975年 | 1篇 |
1964年 | 3篇 |
排序方式: 共有236条查询结果,搜索用时 234 毫秒
121.
Speisman Joseph C.; Lazarus Richard S.; Mordkoff Arnold; Davison Les 《Canadian Metallurgical Quarterly》1964,68(4):367
Previous research had shown that a silent film showing primitive adolescent "subincision" rites produced marked stress reactions. 3 sound tracks were created for the film and compared in impact with the silent version. 1, called the trauma track, pointed up the threatening aspect of the film. The other 2, based upon the theory of ego defense, were designed to encourage defensive interpretations of the film's contents so as to reduce threat. One consisted of denial and reaction formation statements about the film, the other was based on intellectualization. The trauma track increased evidences of stress response especially with respect to continuous recordings of skin conductance during the film. The defensive sound tracks reduced skin conductance evidence of stress response. The effectiveness of the defensive sound tracks interacted with the 2 S groups. Intellectualization was effective for the students and may have been also for the air executives, but denial was not as effective, at least for the student group. The findings supported the importance of the process of cognitive appraisal of threat in producing stress reactions, permitting the conclusion that the same visual stimulus varies in the amount of stress produced depending upon the nature of the cognitive appraisal the person makes regarding its significance for him. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
122.
D'Albora H Anesetti G Lombide P Dees WL Ojeda SR 《Microscopy research and technique》2002,59(6):484-489
Mammalian ovarian function is under endocrine and neural control. Although the extrinsic innervation of the ovary has been implicated in the control of both ovarian development and mature function, it is now clear that, from rats to humans, the ovary is endowed with a network of intrinsic neurons displaying diverse chemical phenotypes. This article describes the presence of these intrinsic neurons in the ovary of different mammalian species, and discusses the possible functions that they may have in the regulation of ovarian physiology. 相似文献
123.
A Software Fault Tree Approach to Requirements Analysis of an Intrusion Detection System 总被引:2,自引:0,他引:2
Guy Helmer Johnny Wong Mark Slagell Vasant Honavar Les Miller Robyn Lutz 《Requirements Engineering》2002,7(4):207-220
Requirements analysis for an intrusion detection system (IDS) involves deriving requirements for the IDS from analysis of
the intrusion domain. When the IDS is, as here, a collection of mobile agents that detect, classify, and correlate system
and network activities, the derived requirements include what activities the agent software should monitor, what intrusion
characteristics the agents should correlate, where the IDS agents should be placed to feasibly detect the intrusions, and
what countermeasures the software should initiate. This paper describes the use of software fault trees for requirements identification
and analysis in an IDS. Intrusions are divided into seven stages (following Ruiu), and a fault subtree is developed to model
each of the seven stages (reconnaissance, penetration, etc.). Two examples are provided. This approach was found to support
requirements evolution (as new intrusions were identified), incremental development of the IDS, and prioritisation of countermeasures.
Correspondence and offprint requests to: G. Helmer, Department of Computer Science, 226 Atanasoff Hall, Iowa State University, Ames, Iowa 50011, USA. Email: ghelmer@cs.iastate.edu 相似文献
124.
125.
Investigated whether student rating instructions would influence the rank ordering by 83 undergraduates of 4 lecture quality sequences, (i.e., whether instructions influence primacy and recency effects). It was also investigated whether affect, self-esteem, and liking would show the same ordering for the 4 lecture quality sequences as ratings. In a laboratory analog of a classroom, using videotaped lectures, initial testing (good or poor Lecture 1), final teaching (good or poor Lecture 2), and student rating instructions (consider only Lecture 2, consider Lectures 1 and 2) were manipulated in a 2?×?2?×?2 design. Effects were measured on final ratings of the instructor, liking for the instructor, S affect, and S self-esteem. For Ss considering only Lecture 2, ratings and liking varied moderately and inversely with Lecture 1 quality (negative primacy effect) and greatly with Lecture 2 quality (positive recency effect), consistent with gain–loss theory. For Ss considering both Lectures 1 and 2, ratings and liking varied moderately with Lecture 1 quality (positive primacy effect) and greatly with Lecture 2 quality (positive recency effect), consistent with reinforcement–affect theory. Evidence failed to show that the effect of lecture quality on liking and ratings was mediated by affect or self-esteem. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
126.
Examined the effects of body image boundaries on preferred and avoided seating choices in small groups and the personal meanings associated with these measures of spatial behavior. Based on the formulation that physical distancing reflects psychological withdrawal, it was hypothesized that more low- than high-barrier Ss would avoid seats nearest the group leaders and prefer seats more distant from the leaders. Second, low-barrier Ss were expected to prefer sitting near the room exit. 56 undergraduates, pretested on the body image boundary variable (Rorschach test), were randomly assigned to 4 unstructured self-study groups. Findings indicate a tendency toward greater defensive distancing by boundary-indefinite Ss. Several limitations of the relationship between boundary definiteness and spatial behavior are articulated. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
The influence of starch-xanthan thickening systems on the sensory, textural and rheological properties of cocoa syrups was studied. The results of whole and partial sensory analyses of syrups obtained under laboratory conditions were presented and compared to those of commercially available syrups. In the evaluation of texture such parameters as hardness, adhesiveness, cohesiveness, gumminess and stringiness were considered. The results of rheological measurements were presented in the form of flow curves as well as viscosity/time and viscosity/ temperature relationships. Flow curves were fitted to the models of Ostwald-de Waele and Casson, which allowed characterising the syrups under study to non-Newtonian, pseudoplastic, and thixotropic fluids. It was concluded that the quantity of thickeners used influenced not only theological, but also textural and sensory properties of the syrups. The decrease of pseudoplasticity and hardness with an increase of xanthan addition was a result of high sugars level in the syrups. This phenomenon was a result of competition between sugars (mono-, di-, and oligosaccharides) and hydrocolloids for water molecules in the systems under study. 相似文献
128.
In this paper the new method of understanding of the curve-polygon object is presented. The method of understanding of the curve-polygon object is part of the research aimed at developing a shape understanding method able to perform complex visual tasks connected with visual thinking. The shape understanding method is implemented as the shape understanding system (SUS). Understanding includes, among others, obtaining the visual concept in process of the visual reasoning, naming and visual explanation by generation an object from a required class. In this paper generation of the object from the selected well defined class, the curve-polygon class, as well as assigning the visual object into one of the shape classes is presented. The generation of the visual objects is used in SUS during learning of the visual concept, explanatory process and self-correcting process. The visual object is assigned into one of the shape classes during the visual reasoning process. The visual reasoning, presented in this paper, in contrast to other forms of reasoning depends on the type of objects which are analysed. In this paper visual reasoning that assigns an object to the curve-polygon class is presented. The shape understanding system consists of different types of experts that perform different processing and reasoning tasks. The self-correcting expert, that implements the new method of testing and reasoning, is invoked to test ability of the system to understand the concept of the curve-polygon shape. 相似文献
129.
130.
Effects of lecturer quality and student perception of lecturer's experience on teacher ratings and student achievement. 总被引:1,自引:0,他引:1
Previous research in college settings on the correlation between teacher ratings and student achievement has produced inconsistent results. Discrepancies may be due to study-to-study differences in teacher and/or student characteristics. 237 university students were tested to investigate a student-based explanation of the discrepancies. Lecturer quality and student perception of lecturer's experience (a student characteristic) were manipulated in a 2?×?2 design in which achievement and ratings were measured. Major findings indicate that (a) the ratings/achievement relationship varied with students' belief about lecturer experience, supporting a student-based explanation of the discrepancies that supplements a previous teacher-based explanation; and (b) lecturer quality affected ratings much more than achievement, threatening the field use of ratings when predictions are made without regression equations about a teacher's impact on student achievement. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献