全文获取类型
收费全文 | 682篇 |
免费 | 18篇 |
国内免费 | 15篇 |
专业分类
电工技术 | 9篇 |
综合类 | 34篇 |
化学工业 | 28篇 |
金属工艺 | 14篇 |
机械仪表 | 45篇 |
建筑科学 | 55篇 |
矿业工程 | 16篇 |
能源动力 | 13篇 |
轻工业 | 20篇 |
水利工程 | 6篇 |
石油天然气 | 8篇 |
武器工业 | 3篇 |
无线电 | 42篇 |
一般工业技术 | 86篇 |
冶金工业 | 112篇 |
原子能技术 | 6篇 |
自动化技术 | 218篇 |
出版年
2023年 | 5篇 |
2022年 | 8篇 |
2021年 | 4篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2017年 | 4篇 |
2016年 | 21篇 |
2015年 | 16篇 |
2014年 | 24篇 |
2013年 | 49篇 |
2012年 | 42篇 |
2011年 | 58篇 |
2010年 | 47篇 |
2009年 | 43篇 |
2008年 | 62篇 |
2007年 | 29篇 |
2006年 | 47篇 |
2005年 | 31篇 |
2004年 | 23篇 |
2003年 | 28篇 |
2002年 | 16篇 |
2001年 | 10篇 |
2000年 | 17篇 |
1999年 | 12篇 |
1998年 | 18篇 |
1997年 | 11篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 9篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1989年 | 6篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
排序方式: 共有715条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.
《Ergonomics》2012,55(2):397-404
Transfer of technology and industrial development without consideration for the characteristics of the local users and the environmental conditions of the recipient countries has proved to be not only socially destructive but economically expensive in terms of human suffering and material losses Most developing countries (DC) are paying an unacceptably high price in terms of suffering, sickness and also loss of production due to work-related accidents Poor working conditions and non-existence of an effective injury prevention programme in many DCs has resulted in a very high sickness and accident rate. In such circumstances, the salary and social benefits of the worker are low, because productivity is well below its capacity. This vicious cycle also results in the worker's malnutrition and low working capacity, resulting in turn in greater vulnerability to disease and job-related accidents A greater awareness is needed among employers and the workforce of such common problems as increased health hazards, poor organization of work, increased night shifts, and a low level of implementing standards and safety regulations Unfortunately, no reliable statistics are available on work-related injuries in DCs. CEDC has started a databank on the ergonomics of developing countries with some limited information on injuries in the workplaces in developing countries. 相似文献
35.
《Measurement》2016
The bidirectional reflectance distribution function (BRDF) is one of the fundamental concepts in such diverse fields as multidimensional reflectometry, computer graphics and computer vision. BRDF manifolds form an infinite-dimensional space, but typically the available measurements are very scarce. Therefore, an efficient learning strategy is crucial when performing the measurements.In this paper, we perform simulation studies within a mathematical framework that allows to establish more efficient BRDF sampling and measurement strategies in the sense of statistical design of experiments and generalized proactive learning. Our simulation studies suggest that the default BRDF measurement strategy is suboptimal for a wide class of loss functions. 相似文献
36.
Spatially continuous data of environmental variables are often required for environmental sciences and management. However, information for environmental variables is usually collected by point sampling, particularly for the mountainous region and deep ocean area. Thus, methods generating such spatially continuous data by using point samples become essential tools. Spatial interpolation methods (SIMs) are, however, often data-specific or even variable-specific. Many factors affect the predictive performance of the methods and previous studies have shown that their effects are not consistent. Hence it is difficult to select an appropriate method for a given dataset. This review aims to provide guidelines and suggestions regarding application of SIMs to environmental data by comparing the features of the commonly applied methods which fall into three categories, namely: non-geostatistical interpolation methods, geostatistical interpolation methods and combined methods. Factors affecting the performance, including sampling design, sample spatial distribution, data quality, correlation between primary and secondary variables, and interaction among factors, are discussed. A total of 25 commonly applied methods are then classified based on their features to provide an overview of the relationships among them. These features are quantified and then clustered to show similarities among these 25 methods. An easy to use decision tree for selecting an appropriate method from these 25 methods is developed based on data availability, data nature, expected estimation, and features of the method. Finally, a list of software packages for spatial interpolation is provided. 相似文献
37.
为了解决尺度不变特征变换(SIFT)算法在图像匹配中匹配正确率低、耗时长等问题,提出一种基于改进网格运动统计特征RANSAC-GMS的图像匹配算法。首先,利用快速旋转不变性特征(ORB)算法对图像进行预匹配,对预匹配的特征点采用网格运动统计(GMS)来支持估计量以实现正确匹配点与错误匹配点的区分;然后,采用改进的随机抽样一致性(RANSAC)算法通过匹配点间的距离相似性对特征点进行筛选,并采用评价函数对筛选后的新数据集进行重新整理,进而实现对误匹配点的剔除。采用Oxford标准图库和现实中拍摄的图像对图像匹配算法进行测试对比,实验结果表明,所提算法在图像匹配中的平均匹配正确率达到91%以上;与GMS、SIFT、ORB等算法相比,该改进算法的近景匹配正确率和远景匹配正确率分别最少提高了16.15个百分点和3.56个百分点,说明它能有效剔除误匹配点,进一步提高图像匹配精度。 相似文献
38.
本文以历年《中国体育事业统计年鉴》中的积累数据为研究对象,通过对各类统计数据表的分析,运用数据库技术和软件工程方法,确定表的结构,建立年鉴数据库;研究运用c#语言设计开发基于网络的c/s模式前端客户端,对数据库进行添加、删除、修改、查询、导出等相关操作,实现对《中国体育事业统计年鉴》数据的网络化管理。 相似文献
39.
Gary G. Koch 《技术计量学》2013,55(4):577-585
A general procedure for estimating the population mean in random effects models of the nested and/of classification type is considered. The suggested estimator is unbiased and consistent (with respect to the structure of the experimental design). It is also optimal with respect to a particular quadratic, location-sensitive criterion. Finally, for experimental designs which contain a certain degree of structural balance, the suggested estimator coincides with the sample mean. 相似文献
40.
William C. Guenther 《技术计量学》2013,55(3):483-498
The linear cost model previously formalized by Hald [4], [5], [9] is reviewed. Techniques are described which permit easy determination of sampling plans based on that model. The degenerate, the beta, and the two point distributions are considered as prior distributions of p, the process fraction defective. For calculations only standard tables and a desk calculator are required. 相似文献