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51.
    
The recent decades have witnessed an unprecedented expansion in the volume of unstructured data in digital textual formats. Companies are now starting to recognize the potential economic value lying untapped in their text data repositories and sources, including external ones, such as social media platforms, and internal ones, such as safety reports and other company-specific document collections. Information extracted from these textual data sources is valuable for a range of enterprise application and for informed decision making. In this article we provide a systematic review of the current state of the art in the application of text analytics in industry. Our review is structured along three dimensions: the application context, the methods and techniques utilized, and the evaluation procedure. Based on the review, we identify the different challenges and constraints that an real-world, industrial environment imposes on text analytics techniques, as opposed to their deployment in more controlled, research environments. In addition, we formulate a set of desiderata that text analytics techniques should satisfy in order to alleviate these challenges and to ensure their successful deployment in industry. Furthermore, we discuss future trends in text analytics and their potential application in industry.  相似文献   
52.
In response to increasing attention from international academia on Chinese gardens, this article advances China’s landscape studies by exploring international research trends on Chinese gardens during the 21st century. It mainly adopts a diachronic perspective to examine the journal Studies in the History of Gardens & Designed Landscapes—a leading journal, and Dumbarton Oaks Research Library and Collection (Trustees for Harvard University)—international academia’s leading institution on landscape studies. Using a bibliometric approach, it first carries out a statistical analysis of the rules and trends of development to explore the distribution patterns of Chinese gardens. Based on this analysis, it uses time series analysis to study the relationships of related academic discourses and contexts. The study reveals that Chinese garden studies led by Chinese scholars has attracted increasing attention from international academia and has involved growing numbers of scholars from various disciplines. Consequently, it has not only shaped much of the output from China and Britain, but is also driving a paradigm shift away from studying Chinese classical gardens to modern designed landscapes, drawing upon a monolithic approach to investigate the pluralistic, and from focusing on Chinese national interaction to transnational interaction.  相似文献   
53.
54.
Lakes in the Finnish Eurowaternet: status and trends   总被引:2,自引:0,他引:2  
The Eurowaternet is a monitoring network designed to cover all European countries, with the overall objective of obtaining timely, quantitative and comparative information on the status of inland waters so that their key environmental problems can be defined, quantified and monitored. Finland launched the Eurowaternet for lakes in 2000. The network was set up according to guidelines of the European Environment Agency (EEA) and was based on national, regional and local monitoring programmes. It includes 253 lake sites, divided into the following groups by, for example, their loading background and size: (i) reference sites, (ii) point-source loading (impact) sites, (iii) agricultural sites, (iv) representative sites, i.e. lakes <100 km(2) with typical water quality in the catchment and (v) lake deep sites in large lakes (>100 km(2)). We examined the water quality and its development during 1976-2001 in these groups, using data from surface and near-bottom water layers at summer and winter stagnation. In addition, the representativeness of the network was evaluated. Summer mean concentrations of total P (TP) during 1990-2001 in surface water were (i) 6.8+/-1.8 microg 1(-1) in reference lakes, (ii) 24+/-5 microg 1(-1) in lakes affected by point loading, (iii) 58+/-32 microg l(-1) in agricultural lakes, (iv) 14+/-2.2 microg l(-1) in representative lakes and (v) 11+/-2.1 microg l(-1) in large lakes. Comparison with reference lakes revealed major impact of human activities on TP and total N (TN)-and consequently on chlorophyll a (a-chl) and transparency-in all other groups, especially agricultural lakes. Decreasing TP and increasing O(2) trends were found at impact sites, reflecting water protection measures taken in pulp and paper mills and municipalities. More surprisingly, we found increasing alkalinity trends in all but agricultural sites and decreasing NO(2)-N+NO(3)-N (NO(x)-N) trends particularly in pelagic areas of large lakes. Comparison of water quality in Eurowaternet lakes with those in randomly sampled lakes (Finnish Lake Survey) revealed that the Eurowaternet covers the entire range of concentrations of TP, TN and conductivity in Finnish lakes, but <1-km(2), eutrophic and/or brown water lakes are underrepresented. Only 0.2% of a total of 13114 small lakes (0.1-1 km(2)) are included in the annual monitoring program of the Eurowaternet.  相似文献   
55.
56.
Lime treatment has been extensively used as a remedial measure against acidification of surface waters. In view of the decreasing acid deposition, the possible consequences of a termination of liming are discussed intensively in Sweden. This paper presents the results of the first study of long-term effects of termination of liming. The temporal trends in water chemistry were studied in two lakes after termination of liming, in a still-limed lake and in an unlimed reference lake. The lime treatment was intentionally stopped in order to evaluate the effects on water chemistry and biota. After the last liming, pH decreased steadily in both reacidifying lakes until annual mean values stabilised around 5.5-6.0 and 6.2-6.5 respectively. ANC and concentrations of non-marine Ca + Mg decreased after the termination of liming. The decreasing pH resulted in increasing trends of inorganic Al (Ali), which during recent years exceeded the lowest known effect level for fish on several occasions. This indicates that the lime treatment may have been terminated to early from an ecological perspective and with respect to the critical load of acidifying substances during the study period. However, during the same time, non-marine sulphate decreased in all lakes in the study and pH and ANC increased in the unlimed reference lake.  相似文献   
57.

Purpose

In France, the bicycle's modal share is stabilizing after a decline; in some of France's major cities, it has even increased since the 1990s. It is hence relevant to improve the knowledge of the injury risk associated with cycling, compared with other means of transport such as car, walking and powered two-wheeler (PTW) riding.

Methods

The injury incidence rates were estimated by the ratio between accident data and mobility (exposure) data. Two accident data sources were used: police data and hospital-based data (outpatients and inpatients) from the Rhône road trauma Registry. This provides four injury categories: all-injury, hospitalization, serious-injury and fatal-injury. Exposure data were estimated from a regional household travel survey (RTS), using three measures of mobility: number of trips, distance traveled and time spent traveling. The survey was carried out from November 2005 to April 2006, on weekdays, outside school and public holidays; this seasonality was corrected using the 2007–2008 national household travel survey (NTS) that covered an entire year. Only information involving accidents and trips in, and residents of, the Rhône County (1.6 million inhabitants, including the city Lyon) were included in our study. Trends of injury rates were also evaluated in Greater Lyon, using previous travel surveys.

Results

The PTW riders had the highest all-injury, hospitalization, serious-injury and fatal-injury rates, followed by cyclists, and lastly by pedestrians and car occupants. The rates between men and women seemed similar among pedestrians and among car occupants. For car occupants, pedestrians and cyclists, the age group 18–25 years had higher all-injury rate compared with the age group 25–65 years. On the contrary, the age group ≥65 years seemed to have higher hospitalization and serious-injury rates, compared with the age group 25–65 years. For cyclists, the injury rates seemed higher in non-dense areas than in dense areas. Between 1996–1997 and 2005–2006 and with regards to time spent traveling, the all-injury, serious-injury and fatal-injury rates seemed to have decreased for car occupants and cyclists.

Conclusion

The higher risk for PTW riders is confirmed and quantified; it is very high. Decrease in injury rates seems more marked for cyclists; this may indicate the “safety in numbers” effect. Countermeasures for improving road safety could be implemented, especially for vulnerable road user types. However, they will not be sufficient to fill in the gap between the much higher risk for PTW riders and that of car occupants. Exposure-based injury rates can be a tool for monitoring and evaluating the effectiveness of policies and programs, and for comparisons between countries.  相似文献   
58.
59.
Deep Learning and its applications have cascaded impactful research and development with a diverse range of modalities present in the real-world data. More recently, this has enhanced research interests in the intersection of the Vision and Language arena with its numerous applications and fast-paced growth. In this paper, we present a detailed overview of the latest trends in research pertaining to visual and language modalities. We look at its applications in their task formulations and how to solve various problems related to semantic perception and content generation. We also address task-specific trends, along with their evaluation strategies and upcoming challenges. Moreover, we shed some light on multi-disciplinary patterns and insights that have emerged in the recent past, directing this field toward more modular and transparent intelligent systems. This survey identifies key trends gravitating recent literature in VisLang research and attempts to unearth directions that the field is heading toward.  相似文献   
60.
国际钨市场分析   总被引:2,自引:0,他引:2  
本文根据笔者于1994年11月3日至4日在美国阿拉巴马州亨茨维尔市召开的在国际钨协(ITIA)第7次年会上搜集到的大量数据和资料,对近几年来国际钨市场的供应和生产、需求量和国内消耗量做了详实的分析,并对今后的发展动向进行了预测.  相似文献   
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