首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   96篇
  免费   6篇
综合类   1篇
化学工业   16篇
金属工艺   4篇
机械仪表   2篇
建筑科学   4篇
能源动力   5篇
轻工业   8篇
无线电   1篇
一般工业技术   23篇
冶金工业   17篇
自动化技术   21篇
  2022年   3篇
  2021年   1篇
  2020年   6篇
  2019年   2篇
  2018年   3篇
  2017年   3篇
  2016年   3篇
  2015年   3篇
  2014年   4篇
  2013年   4篇
  2012年   8篇
  2011年   13篇
  2010年   6篇
  2009年   2篇
  2008年   2篇
  2007年   4篇
  2006年   4篇
  2004年   4篇
  2003年   2篇
  2002年   2篇
  2001年   1篇
  1999年   2篇
  1998年   1篇
  1997年   4篇
  1996年   2篇
  1995年   1篇
  1993年   3篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1986年   1篇
  1983年   2篇
  1981年   1篇
排序方式: 共有102条查询结果,搜索用时 193 毫秒
51.
This article describes a work-in-progress in the framework of a research project aiming at combining requirements engineering methods with formal methods. The main idea is to extend the SysML language with concepts of existing requirements engineering methods. In this article we present extensions to SysML with concepts from the goal model of the KAOS method and we give rules to derive a formal B specification from this goal model. The approach is then illustrated on a case study.  相似文献   
52.
This article presents the use of the particle swarm method to optimize the working cycle of an anthropomorphic manipulator. The working space contained stationary obstacles which made the working cycle difficult. Three objective functions were adopted in the study, concerning trajectory minimization, reduction of electricity consumption and multi-criteria optimization (minimization of both trajectory length and electricity consumption). The effects of selected parameters on the particle swarm optimization (PSO) algorithm and the results of the examinations were analysed.  相似文献   
53.
54.
This paper provides new insights regarding the transfer of information between input signal and the output of neurons. Simulations of the Hodgkin-Huxley (HH) model combined with computational techniques are used to estimate this transfer of information. Our analysis shows that comparatively, mutual information (MI) between input signal and sodium flux is about two times that between input signal and output spikes during each spike within a millisecond-level time domain. This higher transfer of information provided by ionic fluxes extends the working frequency domain of neural cells beyond those accessible to information transfer within spikes alone.  相似文献   
55.
Global challenges in energy   总被引:1,自引:0,他引:1  
Environmental and security concerns are stimulating global interest in hydrogen power, renewable energy, and advanced transportation technologies, but no significant movement away from oil and a carbon-based world economy is expected soon. Over the longer-term, however, a transition from fossil fuels to a non-carbon-based economy will likely occur, affecting the type of environment future generations may encounter. Key challenges will face the world's energy industry over the next few decades to ensure a smooth transition—challenges which will require government and industry solutions beginning as early as today. This paper identifies four critical challenges in energy and the choices which will have to be made on how best to confront growing pollution caused by fossil fuels and how to facilitate an eventual revolutionary-like transition to a non-carbon-based global economy.  相似文献   
56.
OBJECTIVE: To demonstrate that sexual abuse of patients by psychiatrists can be due to a variety of contributors, which may include therapists' psychopathic and narcissistic personality styles. METHOD: Data from a prospective cohort of residents training in psychiatry were examined to evaluate the personality traits of 2 psychiatrists subsequently convicted of boundary violations. RESULTS: The 2 psychiatrists who lost their licenses were identifiable at the beginning of their residency training as individuals with significant character pathology. CONCLUSIONS: For some psychiatrists, repetitive sexual abuse of patients represents one aspect of an ongoing pattern of exploitative relationships. The professional and ethical implications of these findings as they relate to early identification for those at risk are considered.  相似文献   
57.
Review of the anatase to rutile phase transformation   总被引:3,自引:0,他引:3  
Titanium dioxide, TiO2, is an important photocatalytic material that exists as two main polymorphs, anatase and rutile. The presence of either or both of these phases impacts on the photocatalytic performance of the material. The present work reviews the anatase to rutile phase transformation. The synthesis and properties of anatase and rutile are examined, followed by a discussion of the thermodynamics of the phase transformation and the factors affecting its observation. A comprehensive analysis of the reported effects of dopants on the anatase to rutile phase transformation and the mechanisms by which these effects are brought about is presented in this review, yielding a plot of the cationic radius versus the valence characterised by a distinct boundary between inhibitors and promoters of the phase transformation. Further, the likely effects of dopant elements, including those for which experimental data are unavailable, on the phase transformation are deduced and presented on the basis of this analysis.  相似文献   
58.
The daily ileal excretion of amino acids was measured at different food dry matter intakes for the 50 kg liveweight pig under conditions of peptide alimentation. The experiment comprised two cross-over design trials each involving four pairs of entire male pigs fitted with simple T-cannulae at the terminal ileum and fed a hydrolysed casein semi-synthetic diet. Each pair of pigs received one of four sequences of food dry matter intake arranged in a Latin square design, namely 0.06, 0.08, 0.10 and 0.12 (Trial 1) and 0.05, 0.07, 0.09 and 0.11 (Trial 2) of metabolic body weight (W0.75) day?1. Each pig received the diet at its described level of intake for 8 days, with continuous 24 h collection of ileal digesta on the fifth and eighth days. Chromic oxide was included in the diet to permit correction of ileal flows to complete digesta collection. Pooled digesta from each pig at each level of dry matter intake were centrifuged and ultrafiltered and the high-molecular-weight fraction was analysed for amino acid and nitrogen contents. There were significant (P < 0.05) linear relationships between endogenous ileal amino acid, nitrogen and dry matter excretion (mg day?1) and food dry matter intake (g day?1) except for lysine, glutamic acid and phenylalanine which increased in a curvilinear manner (P < 0.05). The results indicate that dietary dry matter intake influences endogenous excretion from the ileum. The relationships, determined under physiological conditions, provide preliminary data on the magnitude of small intestinal amino acid loss in the young growing pig.  相似文献   
59.
In this study, the predictive capacity of the Minnesota Multiphasic Personality Inventory–2 Posttraumatic Stress Disorder–Keane (MMPI–2 PK) scale was examined in a sample of trauma victims who experienced a serious workplace-related accident and subsequent injury. In keeping with a number of previous investigations, the PK scale was largely ineffective in identifying posttraumatic stress disorder (PTSD) beyond overall symptom and functional severity. In contrast, sets of clinical and content scales proved to be significant predictors of PTSD. These findings suggest that the PK scale is not particularly useful in detecting PTSD in civilian trauma samples. Clinicians might be best advised to use the MMPI–2 clinical and content scales in their assessment of PTSD in civilian patients presenting with a history of trauma. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
Sjögren’s syndrome (SS) is a chronic autoimmune disease that affects exocrine glands, primarily the salivary and lachrymal glands. It is characterized by lymphoplasmacytic infiltration of the glandular tissues, ultimately leading to their dysfunction and destruction. Besides classic dry eyes and dry mouth defined as sicca syndrome, patients affected by the disease also typically display symptoms such as fatigue, pain and in more than 50% of cases, systemic manifestations such as arthritis, interstitial lung involvement, neurological involvement and an increased risk of lymphoma. The pathophysiological mechanisms underlying SS still remain elusive. The crucial role of innate immunity has been advocated in recent years regarding the pathogenesis of pSS, especially in the initiation and progression toward autoimmunity. Alarmins are endogenous molecules that belong to the large family of damage associated molecular pattern (DAMP). Alarmins are rapidly released, ensuing cell injury and interacting with pattern recognition receptors (PRR) such as toll-like receptors (TLR) to recruit and activate cells of the innate immune system and to promote adaptive immunity responses. This review highlights the current knowledge of various alarmins and their role in the pathogenesis of pSS.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号