首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3736篇
  免费   511篇
  国内免费   505篇
电工技术   108篇
综合类   364篇
化学工业   84篇
金属工艺   28篇
机械仪表   215篇
建筑科学   51篇
矿业工程   24篇
能源动力   12篇
轻工业   53篇
水利工程   25篇
石油天然气   21篇
武器工业   66篇
无线电   347篇
一般工业技术   192篇
冶金工业   806篇
原子能技术   12篇
自动化技术   2344篇
  2024年   35篇
  2023年   92篇
  2022年   153篇
  2021年   116篇
  2020年   130篇
  2019年   95篇
  2018年   87篇
  2017年   118篇
  2016年   131篇
  2015年   144篇
  2014年   247篇
  2013年   206篇
  2012年   311篇
  2011年   308篇
  2010年   265篇
  2009年   269篇
  2008年   263篇
  2007年   284篇
  2006年   213篇
  2005年   215篇
  2004年   206篇
  2003年   166篇
  2002年   129篇
  2001年   109篇
  2000年   55篇
  1999年   53篇
  1998年   50篇
  1997年   35篇
  1996年   35篇
  1995年   26篇
  1994年   10篇
  1993年   12篇
  1992年   13篇
  1991年   9篇
  1990年   5篇
  1989年   7篇
  1988年   5篇
  1986年   6篇
  1985年   7篇
  1966年   10篇
  1965年   8篇
  1964年   17篇
  1963年   17篇
  1962年   8篇
  1961年   8篇
  1960年   5篇
  1959年   12篇
  1958年   5篇
  1956年   12篇
  1955年   5篇
排序方式: 共有4752条查询结果,搜索用时 15 毫秒
81.
We describe the first shared task for figurative language resolution, which was organised within SemEval-2007 and focused on metonymy. The paper motivates the linguistic principles of data sampling and annotation and shows the task’s feasibility via human agreement. The five participating systems mainly used supervised approaches exploiting a variety of features, of which grammatical relations proved to be the most useful. We compare the systems’ performance to automatic baselines as well as to a manually simulated approach based on selectional restriction violations, showing some limitations of this more traditional approach to metonymy recognition. The main problem supervised systems encountered is data sparseness, since metonymies in general tend to occur more rarely than literal uses. Also, within metonymies, the reading distribution is skewed towards a few frequent metonymy types. Future task developments should focus on addressing this issue.
Malvina NissimEmail:
  相似文献   
82.
This paper presents the core of a software system able to determine a good grasp configuration on 3D objects for a three-fingered hand. The grasp planning problem has been studied considering both the constraints due to the stability and accessibility conditions, and the ones related to functionality. Physical, geometrical, spatial and task-related knowledge for solving the grasp planning problem have been properly modelled to support a heuristic-based reasoning process. A series of heuristic rules and geometric tests are used to scan the solution space, searching for a good grasp. In fact, when considering the three-dimensional case, a purely analytical and exhaustive approach appears too complex because of the dimension of the search space. This approach results in an incremental and modular model of grasp reasoning, that has been implemented using the Flex expert system shell. This work has been developed and demonstrated within the Esprit 2 project CIM-PLATO No. 2202.  相似文献   
83.
在模式识别课程教学中,针对传统线下课程短板,开展线上与线下相结合的混合教学模式教学改革探索。阐述了本课程教学改革的教学环节设计、教学实施方法、考核方式等,以思维导图和综合案例串联庞杂知识点,采用多样化手段,加强对学生创新思维和能力的培养。教学实践证明,该课程教学改革调动了学生主动性,培育了其创新能力与科学精神,丰富了线上线下混合教学改革的理论研究。  相似文献   
84.
新型电力系统的建设促使电力业务范围向用户侧深入,业务种类及数量不断增加。边设备资源有限,只能配置有限数量的服务,任务的时延能耗需求与设备资源有限的矛盾日益突出。为实现云边资源协同与任务的优化调度,提出了一种考虑服务配置的细粒度电力任务云边协同优化调度策略。通过建立微服务的时延与能耗模型,并对任务调度中的约束条件进行分析,将时延与能耗的优化决策问题转化为带约束的多目标优化问题,采用NSGA-Ⅱ算法求解。然后通过基于模糊逻辑的多准则决策方法为任务选择调度方案。仿真结果表明,所提策略在时延和能耗方面的性能优于其他策略,能够适应不同的任务场景并做出最优决策,提高了任务的完成率。  相似文献   
85.
陈彧  张胜  金熠波  钱柱中  陆桑璐 《软件学报》2023,34(12):5940-5956
在过去的近10年中,人工智能相关的服务和应用大规模出现,它们要求高算力、高带宽和低时延.边缘计算目前被认为是这些应用最适合的计算模式,尤其是视频分析相关应用.研究多服务器多用户异构视频分析任务卸载问题,其中用户选择合适的边缘服务器,并将他们的原始视频数据上传至服务器进行视频分析.为了有效处理众多用户对有限网络资源的竞争和共享,并且能够获得稳定的网络资源分配局面,即每个用户不会单方面地改变自己的任务卸载决策,该多服务器多用户异构视频分析任务卸载问题被建模为一个多玩家的博弈问题.基于最小化整体时延的优化目标,先后研究非分布式视频分析场景和分布式视频分析场景两种情形,分别提出基于博弈论的潜在最优服务器选择算法和视频单元分配算法.通过严格的数学证明,两种情形下提出的算法均可以达到纳什均衡,同时保证较低的整体时延.最后,基于真实数据集的大量实验表明,所提方法比其他现有算法降低了平均26.3%的整体时延.  相似文献   
86.
在物联网智能设备任务协作场景中,为解决设备交互不受信以及存在恶意设备破坏协作的问题,提出一种基于区块链的信任管理方案。半分布式的架构克服了集中式和分布式架构的不足,任务协作过程中兼顾了双方的信任,并设计了审查机制确保任务评价的真实可靠。信任的衡量中使用狄利克雷分布模拟任务评价的多样性,构建信任为数个状态,并利用马尔可夫链评估信任状态和全局信任。仿真结果表明,提出的方案可以客观衡量设备的信任,同时在检测恶意设备、提高协作任务成功率及避免误判方面具有优势,因此可以有效确保任务交互的可信和协作环境的安全。  相似文献   
87.
In today’s world, Cloud Computing (CC) enables the users to access computing resources and services over cloud without any need to own the infrastructure. Cloud Computing is a concept in which a network of devices, located in remote locations, is integrated to perform operations like data collection, processing, data profiling and data storage. In this context, resource allocation and task scheduling are important processes which must be managed based on the requirements of a user. In order to allocate the resources effectively, hybrid cloud is employed since it is a capable solution to process large-scale consumer applications in a pay-by-use manner. Hence, the model is to be designed as a profit-driven framework to reduce cost and make span. With this motivation, the current research work develops a Cost-Effective Optimal Task Scheduling Model (CEOTS). A novel algorithm called Target-based Cost Derivation (TCD) model is used in the proposed work for hybrid clouds. Moreover, the algorithm works on the basis of multi-intentional task completion process with optimal resource allocation. The model was successfully simulated to validate its effectiveness based on factors such as processing time, make span and efficient utilization of virtual machines. The results infer that the proposed model outperformed the existing works and can be relied in future for real-time applications.  相似文献   
88.
Nowadays, students often practice problem-solving skills in online learning environments with the help of examples and problems. This requires them to self-regulate their learning. It is questionable how novices self-regulate their learning from examples and problems and whether they need support. The present study investigated the open questions (1) to what extent students' (novices) task selections align with instructional design principles and (2) whether informing them about these principles would improve their task selections, learning outcomes, and motivation. Higher education students (N = 150) learned a problem-solving procedure by fixed sequences of examples and problems (FS-condition), or by self-regulated learning (SRL). The SRL participants selected tasks from a database, varying in format, complexity, and cover story, either with (ISRL-condition) or without (SRL-condition) watching a video detailing the instructional design principles. Students' task-selection patterns in both SRL conditions largely corresponded to the principles, although tasks were built up in complexity more often in the ISRL-condition than in the SRL-condition. Moreover, there was still room for improvement in students' task selections after solving practice problems. The video instruction helped students to better apply certain principles, but did not enhance learning and motivation. Finally, there were no test performance or motivational differences among conditions. Although these findings might suggest it is relatively ‘safe’ to allow students to independently start learning new problems-solving tasks using examples and problems, caution is warranted: It is unclear whether these findings generalize to other student populations, as the students participating in this study have had some experience with similar tasks or learning with examples. Moreover, as there was still room for improvement in students' task selections, follow-up research should investigate how we can further improve self-regulated learning from examples and practice problems.  相似文献   
89.
在国产异构众核平台神威·太湖之光上的非结构网格计算具有稀疏存储、离散访存、数据依赖等特点,严重制约了众核处理器的性能发挥。为解决稀疏存储和离散访存问题,提出一种N阶对角染色算法,以有效平衡主从核计算并利用从核将全局访存转化为LDM访问。针对数据依赖造成的计算竞争问题,采用自适应和无依赖的任务划分方法,避免并行计算时的数据冲突。为对处理器架构和非结构网格计算进行优化,采用主核与从核异步并行的方式,差异化使用主从核以充分利用硬件资源,同时,取消处理器提供的寄存器通信机制,降低从核阵列的同步开销同时便于扩展到新一代神威平台。此外,使用计算访存异步重叠技术来充分隐藏访存延迟。利用SpMV、Integration、calcLudsFcc算子进行实验,结果表明,相比主核实现,组合加速算法在不同算例规模下平均取得了10倍的加速效果,加速比最高可达24倍,N阶对角染色算法相比非染色分块算法取得了超过5.8倍的性能加速,有效提升了数据局部性和计算并行度。该算法对有依赖关系的计算冲突算子同样具有良好的加速性能,验证了自适应和无依赖任务划分方法的有效性。  相似文献   
90.
目的建立与研究基于异步条件下的笔+触控双手交互点击任务人类工效学模型。方法通过18名实验者对于10种不同任务复杂度下的一维异步笔+触控双手点击任务所花费的任务时间进行单因素方差分析以及线性分析,证明该模型的有效性和适用性。结果通过实验我们发现该模型所计算出的任务复杂度对任务时间具有显著影响(F_(9,170)=6.276,P=1.202×10~(-7)),并且该模型调整后的拟合度R~2达到了0.973。结论该模型对于异步条件下的笔+触控双手点击任务具有很强的有效性和适用性。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号