全文获取类型
收费全文 | 1033篇 |
免费 | 13篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 12篇 |
综合类 | 2篇 |
化学工业 | 216篇 |
金属工艺 | 20篇 |
机械仪表 | 14篇 |
建筑科学 | 42篇 |
矿业工程 | 5篇 |
能源动力 | 36篇 |
轻工业 | 49篇 |
水利工程 | 10篇 |
石油天然气 | 2篇 |
无线电 | 85篇 |
一般工业技术 | 197篇 |
冶金工业 | 48篇 |
原子能技术 | 4篇 |
自动化技术 | 305篇 |
出版年
2023年 | 20篇 |
2022年 | 28篇 |
2021年 | 57篇 |
2020年 | 27篇 |
2019年 | 31篇 |
2018年 | 9篇 |
2017年 | 32篇 |
2016年 | 38篇 |
2015年 | 29篇 |
2014年 | 76篇 |
2013年 | 57篇 |
2012年 | 53篇 |
2011年 | 48篇 |
2010年 | 47篇 |
2009年 | 48篇 |
2008年 | 42篇 |
2007年 | 51篇 |
2006年 | 36篇 |
2005年 | 42篇 |
2004年 | 28篇 |
2003年 | 35篇 |
2002年 | 27篇 |
2001年 | 17篇 |
2000年 | 14篇 |
1999年 | 21篇 |
1998年 | 27篇 |
1997年 | 12篇 |
1996年 | 4篇 |
1995年 | 11篇 |
1994年 | 10篇 |
1993年 | 8篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 8篇 |
1987年 | 15篇 |
1986年 | 11篇 |
1985年 | 4篇 |
1983年 | 4篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1974年 | 3篇 |
1972年 | 1篇 |
排序方式: 共有1047条查询结果,搜索用时 218 毫秒
1.
Liu Chunwei Huang Shuigen Blanpain Bart Guo Muxing 《Metallurgical and Materials Transactions B》2019,50(1):271-281
Metallurgical and Materials Transactions B - Basic oxygen furnace (BOF) steel slag is a main byproduct that is produced during the converter steelmaking process. The volume instability and fast... 相似文献
2.
When a vitamin's, pigment's or other food component's chemical degradation follows a known fixed order kinetics, and its rate constant's temperature-dependence follows a two parameter model, then, at least theoretically, it is possible to extract these two parameters from two successive experimental concentration ratios determined during the food's non-isothermal storage. This requires numerical solution of two simultaneous equations, themselves the numerical solutions of two differential rate equations, with a program especially developed for the purpose. Once calculated, these parameters can be used to reconstruct the entire degradation curve for the particular temperature history and predict the degradation curves for other temperature histories. The concept and computation method were tested with simulated degradation under rising and/or falling oscillating temperature conditions, employing the exponential model to characterize the rate constant's temperature-dependence. In computer simulations, the method's predictions were robust against minor errors in the two concentration ratios. The program to do the calculations was posted as freeware on the Internet. The temperature profile can be entered as an algebraic expression that can include ‘If’ statements, or as an imported digitized time–temperature data file, to be converted into an Interpolating Function by the program. The numerical solution of the two simultaneous equations requires close initial guesses of the exponential model's parameters. Programs were devised to obtain these initial values by matching the two experimental concentration ratios with a generated degradation curve whose parameters can be varied manually with sliders on the screen. These programs too were made available as freeware on the Internet and were tested with published data on vitamin A. 相似文献
3.
4.
In this paper, we describe RanGen, a random network generator for generating activity-on-the-node networks and accompanying data for different classes of project scheduling problems. The objective is to construct random networks which satisfy preset values of the parameters used to control the hardness of a problem instance. Both parameters which are related to the network topology and resource-related parameters are implemented. The network generator meets the shortcomings of former network generators since it employs a wide range of different parameters which have been shown to serve as possible predictors of the hardness of different project scheduling problems. Some of them have been implemented in former network generators while others have not. 相似文献
5.
P. Reyniers 《Scientometrics》1992,25(1):59-76
A survey of interlending activities in Dutch-speaking Belgium was taken in order to cordinate future developments. Data on a broad range of topics were collected. The processing of numerical data is outlined. The figures must be put in perspective, due to the presence of estimates. The investigation remains however the first serious attempt to get an overall picture of interlending in Flemish libraries. 相似文献
6.
Steel production is an energy- and water-intensive process: large quantities of water are used for cooling, process and environmental-technical
applications. In the mid-1990s, Arcelor Gent, a large integrated carbon steel producing company in Flanders (Belgium), started
a number of water-related projects: the existing water infrastructure was adapted: the water from the coke plant was biologically
treated; canal water was demineralised using reverse osmosis; waste water from the blast furnaces was neutralised with alkaline
water from the steel plant. As a result of these projects, the quantity of discharged waste water was reduced by a factor
of 2 (water recycling doubled from a factor of 10 to a factor of 20), and the discharge of pollutants decreased. Also resource
consumption decreased: lime used in the steel plant, could be recovered to precipitate Zn in the waste water of the blast
furnaces.
Arcelor Gent obtained for these projects several Environmental Awards. 相似文献
7.
《Environmental Modelling & Software》2007,22(5):630-639
The Water Framework Directive requires Public Participation in River Basin Management (RBM), including previously excluded constituencies besides water experts and policy makers. In this context, the HarmoniCOP project studies ways to improve PP based on the concept of Social Learning (SL). SL refers to the growing capacity of a social network to develop and perform collective actions. Complex issues such as RBM can be better resolved taking into account the diversity of interests and mental frames, and relying on disseminated information and knowledge. Information and Communication tools (IC-tools) can thereby play an important role. In this paper we firstly present our main concepts in relation to SL and PP. Then we propose a provisional qualitative characterisation of the role of IC-tools. Thirdly, we present a framework of analysis to explore IC-tool impact on participatory and SL processes. This framework is used to assess the IC-tools from three perspectives: their technical characteristics, their impact on PP and SL and their usability as perceived by the users. In the fourth part we present a first application of the framework of analysis for two case studies in Flanders and in Dordogne (France). Finally, we discuss some expected future outcomes of the project. 相似文献
8.
Reliability has become a key factor in KBS development. For this reason, it has been suggested that verification and validation (V&V) should become an integrated part of activities throughout the whole KBS development cycle. In this paper, it will be illustrated how the PROLOGA workbench integrates V&V aspects into its modelling environment, such that these techniques can be of assistance in the process of knowledge acquisition and representation. To this end, verification has to be performed incrementally and can no longer be delayed until after the system has been completed. It will be shown how this objective can be realised through an approach that uses the decision table formalism as a modelling instrument. 相似文献
9.
In this paper, we give an overview of the competition formats and the schedules used in 25 European soccer competitions for the season 2008?C2009. We discuss how competitions decide the league champion, qualification for European tournaments, and relegation. Following Griggs and Rosa (Bull. ICA 18:65?C68, 1996), we examine the popularity of the so-called canonical schedule. We investigate the presence of a number of properties related to successive home or successive away matches (breaks) and of symmetry between the various parts of the competition. We introduce the concept of ranking-balancedness, which is particularly useful to decide whether a fair ranking can be made. We also determine how the schedules manage the carry-over effect. We conclude by observing that there is quite some diversity in European soccer schedules, and that current schedules leave room for further optimizing. 相似文献
10.
《Expert systems with applications》2014,41(1):195-209
The processes of logistics service providers are considered as highly human-centric, flexible and complex. Deviations from the standard operating procedures as described in the designed process models, are not uncommon and may result in significant uncertainties. Acquiring insight in the dynamics of the actual logistics processes can effectively assist in mitigating the uncovered risks and creating strategic advantages, which are the result of uncertainties with respectively a negative and a positive impact on the organizational objectives.In this paper a comprehensive methodology for applying process mining in logistics is presented, covering the event log extraction and preprocessing as well as the execution of exploratory, performance and conformance analyses. The applicability of the presented methodology and roadmap is demonstrated with a case study at an important Chinese port that specializes in bulk cargo. 相似文献