全文获取类型
收费全文 | 4583篇 |
免费 | 322篇 |
国内免费 | 286篇 |
专业分类
电工技术 | 320篇 |
技术理论 | 2篇 |
综合类 | 868篇 |
化学工业 | 145篇 |
金属工艺 | 28篇 |
机械仪表 | 242篇 |
建筑科学 | 559篇 |
矿业工程 | 135篇 |
能源动力 | 43篇 |
轻工业 | 132篇 |
水利工程 | 47篇 |
石油天然气 | 93篇 |
武器工业 | 9篇 |
无线电 | 563篇 |
一般工业技术 | 275篇 |
冶金工业 | 293篇 |
原子能技术 | 2篇 |
自动化技术 | 1435篇 |
出版年
2024年 | 20篇 |
2023年 | 35篇 |
2022年 | 86篇 |
2021年 | 141篇 |
2020年 | 138篇 |
2019年 | 98篇 |
2018年 | 89篇 |
2017年 | 93篇 |
2016年 | 118篇 |
2015年 | 146篇 |
2014年 | 349篇 |
2013年 | 356篇 |
2012年 | 328篇 |
2011年 | 349篇 |
2010年 | 256篇 |
2009年 | 305篇 |
2008年 | 282篇 |
2007年 | 325篇 |
2006年 | 288篇 |
2005年 | 234篇 |
2004年 | 258篇 |
2003年 | 221篇 |
2002年 | 197篇 |
2001年 | 157篇 |
2000年 | 74篇 |
1999年 | 66篇 |
1998年 | 32篇 |
1997年 | 28篇 |
1996年 | 25篇 |
1995年 | 20篇 |
1994年 | 12篇 |
1993年 | 7篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1983年 | 2篇 |
1981年 | 2篇 |
1979年 | 3篇 |
1971年 | 3篇 |
1965年 | 4篇 |
1964年 | 2篇 |
1963年 | 3篇 |
1961年 | 5篇 |
1960年 | 2篇 |
1959年 | 3篇 |
1957年 | 2篇 |
1954年 | 2篇 |
排序方式: 共有5191条查询结果,搜索用时 0 毫秒
91.
How to compose existing web services automatically and to guarantee the correctness of the design(e.g. freeness of deadlock and unspecified reception,and temporal constraints) is an important and challenging problem in web services. Most existing approaches require a detailed specification of the desired behaviors of a composite service beforehand and then perform certain formal verification to guarantee the correctness of the design,which makes the composition process both complex and time-consuming. In th... 相似文献
92.
93.
94.
Collaborative business process can become unreliable when business partners collaborate in a peer- based fashion without central
control. Therefore, reliability checking becomes an important issue that needs to be dealt with for any generic solution in
managing business collaboration. In this paper, we propose a novel Choreographical Business Transaction Net (CoBTx-Net) to model collaborative business process and to manage the collaboration by individual participants. Furthermore three reliability
properties named Time-embedded dead marking freeness, Inter-organizational dead marking freeness, and Collaborative soundness are defined based on CoBTx-Net to verify (1) the violation of time constraint, (2) collaborative logic conflicts, and (3)
the improper termination from individual organizations.
相似文献
Lai XuEmail: |
95.
随着当代商品经济的迅速发展,商品的展示设计在商业的竞争和发展中的地位也显得越发突出,它所带来到经济效益也是我们所无法忽视的。中国是当今经济发展速度最快的国家之一,越来越重视商业艺术设计对经济的促进和发展所带来的效果;同时在对其不断的认识和学习中,总结和研究出了适合自身的艺术设计特点,使中国传统文化元素融入到商品的展示中去,达到了市场促销的目的和商品经济的发展,从而使中国的商业艺术快速健康稳步的前进。 相似文献
96.
张宁 《数码设计:surface》2009,(2):52-54
商业插画中视觉张力表现应该具有人文关怀和道德尺度。写作目的在于思索解决问题的方法,倡导创作符合大众审美品位的视觉作品。不要突兀、紧张和过分刺激,应该是积极向上的、从受众心理出发的、互动的视觉感受。创作具有视觉张力的商业插画要以人文关怀为出发点,提高文化内涵和道德修养。分析目前各个信息传达方,他们为推介产品不择手段。一味追求视觉注意,而忽视人文关怀和道德尺度。 相似文献
97.
李小斌 《数码设计:surface》2009,(4):34-36
随着民族文化得到不断的重视和提倡,涌现了一股文化回归的浪潮,具有浓郁淳朴气息的传统包装也越来越多的走向市场,本文基于时代发展的大背景下,结合中国民族的审美特点,以乡土商品运用传统包装为例,试析在大众审美影响下,传统包装所蕴含的商业价值。 相似文献
98.
Relying on the literature on tensions and contradictions and the theory of practice, coupled with the literature on creative industries, this study uncovers how creative entrepreneurs balance the tension between art and business and respond to other challenges of creative entrepreneurship. The multiple case studies method is adopted by examining founders, cofounders and main employees of European film production companies. We reveal the perception of creative entrepreneurs towards the relationship between art and business. We explore different organizational and industry-level challenges experienced by creative entrepreneurs and uncover the organizational practices they adopt to deal with the identified challenges. The research contributes to the phenomenon of creative entrepreneurship by introducing the practice perspective, to the literature on paradox and contradiction by exploring the micro-foundations of tensions and paradox responses in high-intensity situations and to practice-based studies by investigating a domain-specific practice theory and highlighting the agency of creative entrepreneurs in adapting practices necessary to deal with conflicting demands of creative entrepreneurship. 相似文献
99.
Hongting NIU Ying SUN Hengshu ZHU Cong GENG Jiuchun YANG Hui XIONG Bo LANG 《Frontiers of Computer Science》2023,17(3):173319
Business districts are urban areas that have various functions for gathering people, such as work, consumption, leisure and entertainment. Due to the dynamic nature of business activities, there exists significant tidal effect on the boundary and functionality of business districts. Indeed, effectively analyzing the tidal patterns of business districts can benefit the economic and social development of a city. However, with the implicit and complex nature of business district evolution, it is non-trivial for existing works to support the fine-grained and timely analysis on the tidal effect of business districts. To this end, we propose a data-driven and multi-dimensional framework for dynamic business district analysis. Specifically, we use the large-scale human trajectory data in urban areas to dynamically detect and forecast the boundary changes of business districts in different time periods. Then, we detect and forecast the functional changes in business districts. Experimental results on real-world trajectory data clearly demonstrate the effectiveness of our framework on detecting and predicting the boundary and functionality change of business districts. Moreover, the analysis on practical business districts shows that our method can discover meaningful patterns and provide interesting insights into the dynamics of business districts. For example, the major functions of business districts will significantly change in different time periods in a day and the rate and magnitude of boundaries varies with the functional distribution of business districts. 相似文献
100.