全文获取类型
收费全文 | 53148篇 |
免费 | 5855篇 |
国内免费 | 4067篇 |
专业分类
电工技术 | 4477篇 |
技术理论 | 11篇 |
综合类 | 6790篇 |
化学工业 | 1632篇 |
金属工艺 | 1547篇 |
机械仪表 | 3539篇 |
建筑科学 | 4043篇 |
矿业工程 | 1413篇 |
能源动力 | 864篇 |
轻工业 | 2066篇 |
水利工程 | 1266篇 |
石油天然气 | 965篇 |
武器工业 | 1154篇 |
无线电 | 6801篇 |
一般工业技术 | 3840篇 |
冶金工业 | 2905篇 |
原子能技术 | 182篇 |
自动化技术 | 19575篇 |
出版年
2024年 | 268篇 |
2023年 | 677篇 |
2022年 | 1249篇 |
2021年 | 1494篇 |
2020年 | 1656篇 |
2019年 | 1213篇 |
2018年 | 1191篇 |
2017年 | 1527篇 |
2016年 | 1822篇 |
2015年 | 2019篇 |
2014年 | 3655篇 |
2013年 | 3388篇 |
2012年 | 3897篇 |
2011年 | 4190篇 |
2010年 | 3215篇 |
2009年 | 3503篇 |
2008年 | 3606篇 |
2007年 | 3947篇 |
2006年 | 3628篇 |
2005年 | 3183篇 |
2004年 | 2756篇 |
2003年 | 2421篇 |
2002年 | 1828篇 |
2001年 | 1536篇 |
2000年 | 1165篇 |
1999年 | 846篇 |
1998年 | 582篇 |
1997年 | 499篇 |
1996年 | 424篇 |
1995年 | 322篇 |
1994年 | 289篇 |
1993年 | 210篇 |
1992年 | 134篇 |
1991年 | 108篇 |
1990年 | 80篇 |
1989年 | 76篇 |
1988年 | 61篇 |
1987年 | 42篇 |
1986年 | 35篇 |
1985年 | 36篇 |
1984年 | 45篇 |
1983年 | 40篇 |
1982年 | 24篇 |
1981年 | 18篇 |
1980年 | 25篇 |
1979年 | 18篇 |
1977年 | 10篇 |
1965年 | 14篇 |
1964年 | 16篇 |
1961年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 155 毫秒
1.
如何在互联网时代打造一个信息化的管理模式,已经成为广大学校图书管理发展过程中亟待处理的问题。文章就互联网时代下的高职图书管理信息化建设进行了详细探讨,以期能够给广大同仁提供一些借鉴参考,共同为图书管理工作的现代化改革和发展贡献力量。 相似文献
2.
文章首先对智能化电子信息技术进行了深入的研究,而后分析了该技术在应用过程中出现的问题,最后结合该技术的相关特点给出了相应的问题解决措施,希望能够对智能化电子信息技术的发展提供帮助。 相似文献
3.
In actual engineering scenarios, limited fault data leads to insufficient model training and over-fitting, which negatively affects the diagnostic performance of intelligent diagnostic models. To solve the problem, this paper proposes a variational information constrained generative adversarial network (VICGAN) for effective machine fault diagnosis. Firstly, by incorporating the encoder into the discriminator to map the deep features, an improved generative adversarial network with stronger data synthesis capability is established. Secondly, to promote the stable training of the model and guarantee better convergence, a variational information constraint technique is utilized, which constrains the input signals and deep features of the discriminator using the information bottleneck method. In addition, a representation matching module is added to impose restrictions on the generator, avoiding the mode collapse problem and boosting the sample diversity. Two rolling bearing datasets are utilized to verify the effectiveness and stability of the presented network, which demonstrates that the presented network has an admirable ability in processing fault diagnosis with few samples, and performs better than state-of-the-art approaches. 相似文献
4.
Safa Meraghni Labib Sadek Terrissa Meiling Yue Jian Ma Samir Jemei Noureddine Zerhouni 《International Journal of Hydrogen Energy》2021,46(2):2555-2564
Prognostics and health management of proton exchange membrane fuel cell (PEMFC) systems have driven increasing research attention in recent years as the durability of PEMFC stack remains as a technical barrier for its large-scale commercialization. To monitor the health state during PEMFC operation, digital twin (DT), as a smart manufacturing technique, is applied in this paper to establish an ensemble remaining useful life prediction system. A data-driven DT is constructed to integrate the physical knowledge of the system and a deep transfer learning model based on stacked denoising autoencoder is used to update the DT with online measurement. A case study with experimental PEMFC degradation data is presented where the proposed data-driven DT prognostics method has applied and reached a high prediction accuracy. Furthermore, the predicted results are proved to be less affected even with limited measurement data. 相似文献
5.
6.
Karolina Storesund Francine Amon Anne Steen‐Hansen Shayesteh Haghighatpanah Ida Larsson 《火与材料》2021,45(1):181-190
The aim of this exploratory study has been to investigate the fire properties and environmental aspects of different upholstery material combinations, mainly for domestic applications. An analysis of the sustainability and circularity of selected textiles, along with lifecycle assessment, is used to qualitatively evaluate materials from an environmental perspective. The cone calorimeter was the primary tool used to screen 20 different material combinations from a fire performance perspective. It was found that textile covers of conventional fibres such as wool, cotton and polyester, can be improved by blending them with fire resistant speciality fibres. A new three‐dimensional web structure has been examined as an alternative padding material, showing preliminary promising fire properties with regard to ignition time, heat release rates and smoke production. 相似文献
7.
Benjarat Tepsongkroh Kamolwan Jangchud Anuvat Jangchud Pitchayapat Chonpracha Ryan Ardoin Witoon Prinyawiwatkul 《International Journal of Food Science & Technology》2020,55(1):46-54
Effects of mushroom type, seasoning and health benefit information (HBI) on consumers’ saltiness expectation, sensory liking, elicited emotions and purchase intent (PI) of extruded snacks were investigated. Five snacks were evaluated: straw mushroom (Volvariella volvacea) extrudates without (SME) or with seasoning (SMES), phoenix mushroom (Pleurotus pulmonarius) extrudates without (PME) or with seasoning (PMES), and the control without mushroom and seasoning. Hedonic scores and positive emotions were generally higher for seasoned mushroom-containing snacks (SMES and PMES) with 65% and 75.83% of consumers reporting willingness to purchase, respectively, after receiving HBI. Bored, interested and satisfied were identified as significant emotional predictors for PI odds. Flavour, saltiness, overall liking, bored, good and interested were critical attributes, differentiating snacks. This study demonstrated that sensory liking and PI of extruded brown rice-based snacks containing mushroom could be improved through savoury seasoning addition, which also allowed saltiness expectations to be met. 相似文献
8.
Massive Open Online Courses (MOOCs) are becoming an essential source of information for both students and teachers. Noticeably, MOOCs have to adapt to the fast development of new technologies; they also have to satisfy the current generation of online students. The current MOOCs’ Management Systems, such as Coursera, Udacity, edX, etc., use content management platforms where content are organized in a hierarchical structure. We envision a new generation of MOOCs that support interpretability with formal semantics by using the SemanticWeb and the online social networks. Semantic technologies support more flexible information management than that offered by the current MOOCs’ platforms. Annotated information about courses, video lectures, assignments, students, teachers, etc., can be composed from heterogeneous sources, including contributions from the communities in the forum space. These annotations, combined with legacy data, build foundations for more efficient information discovery in MOOCs’ platforms. In this article we review various Collaborative Semantic Filtering technologies for building Semantic MOOCs’ management system, then, we present a prototype of a semantic middle-sized platform implemented at Western Kentucky University that answers these aforementioned requirements. 相似文献
9.
10.
Naoki Yokokawa Yutaro Masuda Eri Amasawa Hirokazu Sugiyama Masahiko Hirao 《Packaging Technology and Science》2020,33(11):445-459
This study presents systematic packaging design tools integrating functional and environmental consequences on product life cycle. To design packaging for sustainability, the trade-offs between functional and environmental aspects of packaging throughout the product life cycle should be considered. However, it is difficult for packaging designers to understand the overall trade-offs because the extent of the design consequences on the entire life cycle of packaging and its contents is unclear. We developed two tools for packaging design: the Life Cycle Association Matrix (LCAM) and the Function Network Diagram (FND). The following three steps, based on literature reviews and interviews with industrial experts, were applied. Firstly, we listed the product functions and design variables related to the functions as the attributes allocated to the product life cycle. Secondly, the attributes were connected appropriately based on causal relationships. Lastly, we identified the factors to support decision making in the packaging design procedure. As a result, the LCAM depicts the design consequences on the life cycle, and the FND determines the stakeholders affected by the design consequences. Two case studies were demonstrated to analyze the trade-offs by using our tools. In the case studies, a liquid laundry detergent bottle and a milk carton were redesigned. The tools identified the design consequences and stakeholders affected by the redesign of the usability and protective function for the detergent and milk cases, respectively. The results showed the significance of understanding the design consequences on the product life cycle by integrating the functional and environmental aspects. 相似文献