全文获取类型
收费全文 | 115706篇 |
免费 | 10939篇 |
国内免费 | 5976篇 |
专业分类
电工技术 | 6952篇 |
技术理论 | 11篇 |
综合类 | 8374篇 |
化学工业 | 18891篇 |
金属工艺 | 6322篇 |
机械仪表 | 7025篇 |
建筑科学 | 8726篇 |
矿业工程 | 3059篇 |
能源动力 | 3039篇 |
轻工业 | 10446篇 |
水利工程 | 2386篇 |
石油天然气 | 5538篇 |
武器工业 | 980篇 |
无线电 | 13759篇 |
一般工业技术 | 13853篇 |
冶金工业 | 5074篇 |
原子能技术 | 1285篇 |
自动化技术 | 16901篇 |
出版年
2024年 | 454篇 |
2023年 | 1844篇 |
2022年 | 3414篇 |
2021年 | 4790篇 |
2020年 | 3671篇 |
2019年 | 3035篇 |
2018年 | 3465篇 |
2017年 | 3590篇 |
2016年 | 3505篇 |
2015年 | 4695篇 |
2014年 | 5919篇 |
2013年 | 7096篇 |
2012年 | 8001篇 |
2011年 | 8819篇 |
2010年 | 7639篇 |
2009年 | 7372篇 |
2008年 | 7217篇 |
2007年 | 6771篇 |
2006年 | 6304篇 |
2005年 | 5359篇 |
2004年 | 3929篇 |
2003年 | 3270篇 |
2002年 | 3026篇 |
2001年 | 2637篇 |
2000年 | 2512篇 |
1999年 | 2612篇 |
1998年 | 2074篇 |
1997年 | 1700篇 |
1996年 | 1634篇 |
1995年 | 1339篇 |
1994年 | 1159篇 |
1993年 | 838篇 |
1992年 | 644篇 |
1991年 | 475篇 |
1990年 | 396篇 |
1989年 | 351篇 |
1988年 | 252篇 |
1987年 | 176篇 |
1986年 | 130篇 |
1985年 | 87篇 |
1984年 | 65篇 |
1983年 | 50篇 |
1982年 | 65篇 |
1981年 | 34篇 |
1980年 | 37篇 |
1979年 | 24篇 |
1978年 | 15篇 |
1977年 | 19篇 |
1976年 | 26篇 |
1974年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
汽车用塑料注塑新技术的进展 总被引:1,自引:0,他引:1
综述了汽车用塑料的注射成型技术的进展,简单介绍了气体辅助注射成型(GAIM)、水辅助注射成型、熔芯注射成型、反应注射/增强反应注射(RIM/RRIM)成型等技术的特点、生产的汽车部件及最新动向。 相似文献
994.
我国大学毕业生就业形势日趋严峻,就业问题已经引起了社会的广泛关注,社会各界都在为大学生就业出主意、想办法.笔者对目前毕业生就业中的几对矛盾及其化解作了一些探索,本文就如何解决这些矛盾谈一点看法. 相似文献
995.
In a large-scale locality-driven network such as in modular robotics and wireless sensor networks, knowing the state of a local area is sometimes necessary due to either interactions being local and driven by neighborhood proximity or the users being interested in the state of a certain region. We define locality-aware predicates (LAP) that aim at detecting a predicate within a specified area. We model the area of interest as the set of processes that are within a breadth-first search tree (BFST) of height k rooted at the initiator process. Although a locality-aware predicate specifies a predicate only within a local area, observing the area consistently requires considering the entire system in a consistent manner. This raises the challenge of making the complexities of the corresponding predicate detection algorithms scale-free, i.e., independent of the size of the system. Since all existing algorithms for getting a consistent view of the system require either a global snapshot of the entire system or vector clocks of the size of the system, a new solution is needed. We focus on stable LAP, which are those LAP that remain true once they become true. We propose a scale-free algorithm to detect stable LAP within a k-height BFST. Our algorithm can detect both stable conjunctive LAP and stable relational LAP. In the process of designing our algorithm, we also propose the first distributed algorithm for building a BFST within an area of interest in a graph, and the first distributed algorithm for recording a consistent sub-cut within the area of interest. This paper demonstrates that LAPs are a natural fit for detecting distributed properties in large-scale distributed systems, and stable LAPs can be practically detected at low cost. 相似文献
996.
本文主要对无机非金属材料晶体因固溶外来离子而对晶体强度和韧性的贡献进行阐述。本文从固溶类型、点阵畸变、畸变应力着手进行讨论。 相似文献
997.
Interaction‐Feature Enhanced Multiuser Model Learning for a Home Environment Using Ambient Sensors
下载免费PDF全文
![点击此处可从《国际智能系统杂志》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Activity recognition (AR) is a key enabler for a context‐aware smart home since knowing what the residents’ current activities helps a smart home provide more desirable services. This is why AR is often used in assistive technologies for cognitively impaired people to evaluate their abilities to undertake activities of daily living. In a real‐life scenario, multiple‐resident AR has been considered as a very challenging problem, primarily due to the complexity of data association. In addition, most prior research has not considered the potential interpersonal interactions among residents to simplify complexity, especially in an environment monitored by ambient sensors. In this study, we propose two types of multiuser activity models, both of which are derived from an interaction‐feature enhanced multiuser model learning framework. These two models consider interpersonal interactions and data association for multiuser AR using ambient sensors. We then compare their performance with the other two baseline models with or without consideration of data association and interpersonal interactions. The experimental results show that the derived models outperform other baseline classifiers. Therefore, the proposed approach can increase the opportunities for providing context‐aware services for a multiresident smart home. 相似文献
998.
叙述了以废聚酯饮料瓶为原料,经过醇解、酯化以及缩聚等工艺过程,制成透明聚酯清漆。该法为废饮料瓶回收利用开辟了可行之路,也为聚酯清漆找到了廉价的原材料。 相似文献
999.
介绍了中国石化成品油二次物流配送优化系统的开发、建设过程以及实施效果,提出了进一步提升该系统的建议. 相似文献
1000.