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   130篇
  免费   2篇
电工技术   2篇
化学工业   21篇
金属工艺   2篇
建筑科学   1篇
能源动力   3篇
轻工业   28篇
无线电   20篇
一般工业技术   11篇
冶金工业   26篇
原子能技术   1篇
自动化技术   17篇
  2022年   1篇
  2021年   9篇
  2019年   4篇
  2018年   4篇
  2017年   5篇
  2016年   4篇
  2015年   2篇
  2014年   6篇
  2013年   10篇
  2011年   6篇
  2010年   3篇
  2009年   3篇
  2008年   6篇
  2007年   2篇
  2006年   3篇
  2005年   6篇
  2004年   7篇
  2003年   3篇
  2002年   3篇
  2001年   4篇
  1999年   1篇
  1998年   12篇
  1997年   8篇
  1996年   6篇
  1995年   2篇
  1994年   2篇
  1993年   2篇
  1992年   2篇
  1991年   2篇
  1990年   1篇
  1988年   1篇
  1984年   1篇
  1975年   1篇
排序方式: 共有132条查询结果,搜索用时 0 毫秒
101.

This article presents the STROBE model: both an agent representation and an agent communication, model based on a social approach, which means interaction centered. This model represents how agents may realize the interactive, dynamic generation of services on the Grid. Dynamically generated services embody a new concept of service implying a collaborative creation of knowledge, i.e., learning; services are constructed interactively between agents depending on a conversation. The approach consists of integrating selected features from multi-agent systems and agent communication, language interpretation in applicative/functional programming and e-learning/human-learning into a unique, original, and simple view that privileges interactions, including control. The main characteristic of STROBE agents is that they develop a language (environment + interpreter) for each of their interlocutors. The model is inscribed within a global approach, defending a shift from the classical algorithmic (control based) view to problem solving in computing to an interaction-based view of social informatics, where artificial as well as human agents operate by communicating as well as by computing. The paper shows how the model may not only account for the classical communicating agent approaches, but also represent a fundamental advance in modeling societies of agents in particular in dynamic service generation scenarios such as those necessary today on the Web and proposed tomorrow for the Grid. Preliminary concrete experimentations illustrate the potential of the model; they are significant examples for a very wide class of computational and learning situations.  相似文献   
102.
Since 2000, the southwestern Brazilian Amazon has undergone a rapid transformation from natural vegetation and pastures to row-crop agricultural with the potential to affect regional biogeochemistry. The goals of this research are to assess wavelet algorithms applied to MODIS time series to determine expansion of row-crops and intensification of the number of crops grown. MODIS provides data from February 2000 to present, a period of agricultural expansion and intensification in the southwestern Brazilian Amazon. We have selected a study area near Comodoro, Mato Grosso because of the rapid growth of row-crop agriculture and availability of ground truth data of agricultural land-use history. We used a 90% power wavelet transform to create a wavelet-smoothed time series for five years of MODIS EVI data. From this wavelet-smoothed time series we determine characteristic phenology of single and double crops. We estimate that over 3200 km2 were converted from native vegetation and pasture to row-crop agriculture from 2000 to 2005 in our study area encompassing 40,000 km2. We observe an increase of 2000 km2 of agricultural intensification, where areas of single crops were converted to double crops during the study period.  相似文献   
103.
Interstitial lung diseases (ILDs) that are known as diffuse parenchymal lung diseases (DPLDs) lead to the damage of alveolar epithelium and lung parenchyma, culminating in inflammation and widespread fibrosis. ILDs that account for more than 200 different pathologies can be divided into two groups: ILDs that have a known cause and those where the cause is unknown, classified as idiopathic interstitial pneumonia (IIP). IIPs include idiopathic pulmonary fibrosis (IPF), non-specific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia (COP) known also as bronchiolitis obliterans organizing pneumonia (BOOP), acute interstitial pneumonia (AIP), desquamative interstitial pneumonia (DIP), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), and lymphocytic interstitial pneumonia (LIP). In this review, our aim is to describe the pathogenic mechanisms that lead to the onset and progression of the different IIPs, starting from IPF as the most studied, in order to find both the common and standalone molecular and cellular key players among them. Finally, a deeper molecular and cellular characterization of different interstitial lung diseases without a known cause would contribute to giving a more accurate diagnosis to the patients, which would translate to a more effective treatment decision.  相似文献   
104.
Two hybrid combined cycle electrical power generating schemes burning coal and natural gas were examined using the ECLIPSE chemical process simjlator. The results of these simulations are presented and analyzed. Comparison is made with conventional power generation technologies. Two additional pieces of work are included. The first examines the effect of the hot gas filtration operating conditions on the hybrid combined cycle efficiency and the second calculates the allowable increase in capital cost for a specified improvement in power plant efficiency while maintaining the same cost of electricity.  相似文献   
105.
106.
To develop real-time vision applications for use in highly dynamic environments, such as automotive traffic, researchers must gather large amounts of data from different sensors and systems at different rates. Software capable of real-time data acquisition, synchronization, logging, and - ultimately - data processing and visualization is fundamentally important to improving researcher efficiency. The general obstacle and lane detection framework supports different devices and makes it easy to add new system functionalities. GOLD can easily become the engine for many automotive applications, and it could work in other application domains as well.  相似文献   
107.
The identification of new biomarkers allowing an early and more accurate characterization of patients with ST-segment elevation myocardial infarction (STEMI) is still needed, and exosomes represent an attractive diagnostic tool in this context. However, the characterization of their protein cargo in relation to cardiovascular clinical manifestation is still lacking. To this end, 35 STEMI patients (17 experiencing resuscitated out-of-hospital cardiac arrest (OHCA-STEMI) and 18 uncomplicated) and 32 patients with chronic coronary syndrome (CCS) were enrolled. Plasma exosomes were characterized by the nanoparticle tracking analysis and Western blotting. Exosomes from STEMI patients displayed a higher concentration and size and a greater expression of platelet (GPIIb) and vascular endothelial (VE-cadherin) markers, but a similar amount of cardiac troponin compared to CCS. In addition, a difference in exosome expression of acute-phase proteins (ceruloplasmin, transthyretin and fibronectin) between STEMI and CCS patients was found. GPIIb and brain-associated marker PLP1 accurately discriminated between OHCA and uncomplicated STEMI. In conclusion, the exosome profile of STEMI patients has peculiar features that differentiate it from that of CCS patients, reflecting the pathophysiological mechanisms involved in STEMI. Additionally, the exosome expression of brain- and platelet-specific markers might allow the identification of patients experiencing ischemic brain injury in STEMI.  相似文献   
108.
This paper presents a comparative study of six methods for the retrieval and classification of textured 3D models, which have been selected as representative of the state of the art. To better analyse and control how methods deal with specific classes of geometric and texture deformations, we built a collection of 572 synthetic textured mesh models, in which each class includes multiple texture and geometric modifications of a small set of null models. Results show a challenging, yet lively, scenario and also reveal interesting insights into how to deal with texture information according to different approaches, possibly working in the CIELab as well as in modifications of the RGB colour space.  相似文献   
109.
A series of digitalis-like compounds, with the lactone ring shifted from the original position through a spacer or replaced by a series of guanylhydrazone substituent-bearing chains, was synthesized and evaluated for inhibition of Na+,K(+)-ATPase and for inotropic activity. The highest Na+,K(+)-ATPase inhibition (IC50) and inotropic activity (EC50) were reached with the vinylogous guanylhydrazone 5 where a cardenolide-like polarized alpha,beta-unsaturated system and a basic guanidino group were both present at the 17 beta-position; for this compound IC50 and EC50 values were comparable to or higher than those of Thomas' parent guanylhydrazone 1, digitoxigenin, and digoxin. A substantial improvement of the desired positive inotropic activity versus the toxic arrhythmogenic concentration was not reached within this series; only a slightly better therapeutic index can be envisaged for compounds 5 and 4, even though, for the latter, to the detriment of potency, presumably because of a weaker interaction with the receptor, due to the lack of a cardenolide-like polarized system.  相似文献   
110.
A method for determination in vivo of the benzylpenicillin residues in ovine milk at low levels was described. Two groups of Sardinian breed sheep were treated with a dose of penicillin G sodium salt by intramammary infusion and intramuscular administration respectively. The residues were detected by isocratic HPLC method of the extract obtained from a previous cleanup procedure. Linear calibration plots were obtained over a large concentration range of 1 mg ml-1 -10 ng ml-1, with correlation coefficients greater than 0.998. Recoveries between 78.6 and 87.3% were obtained. Limit of detection (LOD) and limit of determination (LOQ) were 2.6 and 8.8 ng ml-1 respectively. This method would be useful for routine monitoring of penicillin G residues in ovine dairy milk.  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