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21.
针对不同厂商、不同系统的楼宇自控设备互操作、互通信的局限性,分析了BACnet/IP技术和实时数据库,设计开发了一种基于BACnet/IP技术的实时数据库DasRdb的设备驱动程序。该设备驱动程序采用UDP通信方式,通过调用每个BACnet/IP设备的标准接口函数来驱动实时数据库DasRdb分别进行写操作和读操作,能够有效地实现BACnet/IP设备与实时数据库DasRdb之间的通信,从而使楼控设备的互操作成为可能。现场工程应用表明,该程序的运行契合BACnet的一致性要求,具有简单、高效、精确度高、实时性好的特点。 相似文献
22.
Kaiyu Zhao Matthew O. Ward Elke A. Rundensteiner Huong N. Higgins 《Computer Graphics Forum》2014,33(3):331-340
Linear models are commonly used to identify trends in data. While it is an easy task to build linear models using pre‐selected variables, it is challenging to select the best variables from a large number of alternatives. Most metrics for selecting variables are global in nature, and thus not useful for identifying local patterns. In this work, we present an integrated framework with visual representations that allows the user to incrementally build and verify models in three model spaces that support local pattern discovery and summarization: model complementarity, model diversity, and model representivity. Visual representations are designed and implemented for each of the model spaces. Our visualizations enable the discovery of complementary variables, i.e., those that perform well in modeling different subsets of data points. They also support the isolation of local models based on a diversity measure. Furthermore, the system integrates a hierarchical representation to identify the outlier local trends and the local trends that share similar directions in the model space. A case study on financial risk analysis is discussed, followed by a user study. 相似文献
23.
S. Chaturvedi C. Dunne Z. Ashktorab R. Zachariah B. Shneiderman 《Computer Graphics Forum》2014,33(8):52-68
An important part of network analysis is understanding community structures like topological clusters and attribute‐based groups. Standard approaches for showing communities using colour, shape, rectangular bounding boxes, convex hulls or force‐directed layout algorithms remain valuable, however our Group‐in‐a‐Box meta‐layouts add a fresh strategy for presenting community membership, internal structure and inter‐cluster relationships. This paper extends the basic Group‐in‐a‐Box meta‐layout, which uses a Treemap substrate of rectangular regions whose size is proportional to community size. When there are numerous inter‐community relationships, the proposed extensions help users view them more clearly: (1) the Croissant–Doughnut meta‐layout applies empirically determined rules for box arrangement to improve space utilization while still showing inter‐community relationships, and (2) the Force‐Directed layout arranges community boxes based on their aggregate ties at the cost of additional space. Our free and open source reference implementation in NodeXL includes heuristics to choose what we have found to be the preferable Group‐in‐a‐Box meta‐layout to show networks with varying numbers or sizes of communities. Case study examples, a pilot comparative user preference study (nine participants), and a readability measure‐based evaluation of 309 Twitter networks demonstrate the utility of the proposed meta‐layouts. 相似文献
24.
《International journal of human-computer studies》2014,72(3):337-348
The last 2 decades have seen a constantly increasing interest in mindfulness, due to its positive effects on health and well-being. Recently, a number of mobile applications aimed at supporting people in practicing mindfulness techniques have appeared, but their efficacy has not been formally evaluated yet. In this paper, we first introduce the reader to mindfulness techniques, traditional as well as computer-based. Then, we propose and evaluate a mobile application (called AEON) aimed at helping users in practicing thought distancing, i.e. a mindfulness technique that requires one not to react in response to his/her thoughts but to be aware of them and observe them while they go away. AEON allows the user to enter his/her thoughts and visualize them as written in ink on a parchment placed under water. By touching the screen, the user can interact with the water and produce waves that progressively dissolve each written thought. We evaluate AEON on a sample of naive meditators (i.e. people with no or minimal experience with meditation), contrasting it with two traditional thought distancing techniques that are not computer-based. The first traditional technique requires users to mentally visualize their thoughts as printed on clouds and observe them as they pass by, while the second requires users to write their thoughts on cards, then pick up the cards one at a time, look at them and toss them into a wastepaper basket. AEON obtained better results in terms of achieved mindfulness, perceived level of difficulty and degree of pleasantness. Since practicing mindfulness tends to be difficult for naive meditators, these results suggest that AEON can be a novel and effective way to help them approach mindfulness. 相似文献
25.
《International journal of human-computer studies》2014,72(6):552-566
We compared two versions of a touch-screen digital thermostat using a framework encompassing several user experience (UX) characteristics, and here describe how the implementation of certain design factors (specialists, praises, tooltips and increased interactivity) was done on mixed-fidelity prototypes of the user interface. We illustrate how the experimental comparison, involving 20 university students and 20 older adults, revealed important differences in UX, including perceived ease of use, behavioral intentions, enjoyment, quality, satisfaction, trust and usability, measured mainly through established questionnaires.Analysis revealed that using that kind of artifacts is a very cost effective way to elicit interesting and useful results; many UX variables are significantly affected by design factors and by age differences, as expected; effects of design factors go well beyond usability and therefore could not be caught by running an investigation focused only on usability.Age difference matters: older adults do not respond to addition of specialists, praises and tooltips as younger users do. We argue that potential benefits of these design choices are outweigh by the increase in complexity of the user interface.From a methodological viewpoint we suggest using a particular array of UX characteristics and metrics when testing mixed-fidelity prototypes. Not all the metrics that we adopted were equally useful, and in particular perceived usability, subjective mental effort, and emotions did not help us highlighting differences. 相似文献
26.
《International journal of human-computer studies》2014,72(12):783-795
This paper investigates how social distance can serve as a lens through which we can understand human–robot relationships and develop guidelines for robot design. In two studies, we examine the effects of distance based on physical proximity (proxemic distance), organizational status (power distance), and task structure (task distance) on people׳s experiences with and perceptions of a humanlike robot. In Study 1, participants (n=32) played a card-matching game with a humanlike robot. We manipulated the power distance (supervisor vs. subordinate) and proxemic distance (close vs. distant) between participants and the robot. Participants who interacted with the supervisor robot reported a more positive user experience when the robot was close than when the robot was distant, while interactions with the subordinate robot resulted in a more positive experience when the robot was distant than when the robot was close. In Study 2, participants (n=32) played the game in two different task distances (cooperation vs. competition) and proxemic distances (close vs. distant). Participants who cooperated with the robot reported a more positive experience when the robot was distant than when it was close. In contrast, competing with the robot resulted in a more positive experience when it was close than when the robot was distant. The findings from the two studies highlight the importance of consistency between the status and proxemic behaviors of the robot and of task interdependency in fostering cooperation between the robot and its users. This work also demonstrates how social distance may guide efforts toward a better understanding of human–robot interaction and the development of effective design guidelines. 相似文献
27.
This paper describes the design and application of the Atmospheric Evaluation and Research Integrated model for Spain (AERIS). Currently, AERIS can provide concentration profiles of NO2, O3, SO2, NH3, PM, as a response to emission variations of relevant sectors in Spain. Results are calculated using transfer matrices based on an air quality modelling system (AQMS) composed by the WRF (meteorology), SMOKE (emissions) and CMAQ (atmospheric-chemical processes) models. The AERIS outputs were statistically tested against the conventional AQMS and observations, revealing a good agreement in both cases. At the moment, integrated assessment in AERIS focuses only on the link between emissions and concentrations. The quantification of deposition, impacts (health, ecosystems) and costs will be introduced in the future. In conclusion, the main asset of AERIS is its accuracy in predicting air quality outcomes for different scenarios through a simple yet robust modelling framework, avoiding complex programming and long computing times. 相似文献
28.
封侣 《电脑编程技巧与维护》2014,(2):16-18,30
用户与角色关联,角色与权限关联,角色是连接用户与权限的桥梁。通过这样的设计,可防止有相同权限的用户重复分配权限,而只是分配在同一角色下便可。此设计已经成功在COSL IT支持服务中心《党群在线服务平台》系统中应用,系统中的权限模块正常工作,保障了《党群在线服务平台》良好运行。 相似文献
29.
提出了一种基于监控日志挖掘的移动应用用户访问模型自动构造方法,该方法包括监控代码注入和界面访问模型构造两部分。首先,提出了一种监控代码自动注入方法,即通过对移动应用代码的静态分析,自动地在相应位置插入监控代码以支持在运行时动态地监控用户的访问行为。其次,提出了一种基于状态机的移动应用用户访问模型构造方法。访问模型中状态机的节点和节点间跳转上的附加属性描述了UI界面之间的跳转行为和界面内控件的使用情况。对移动应用进行的实验表明,这种基于监控日志挖掘的移动应用用户访问模型自动构造方法能够成功地自动注入移动应用的监控代码,并能够有效获得移动应用用户界面访问行为。 相似文献
30.
基于用户兴趣的不同,研究如何针对用户的浏览行为来获取用户的有效兴趣数据,并根据现有用户兴趣模型存在的不足,结合Web挖掘中的相关技术,先显式构建用户兴趣模型,后隐式更新用户兴趣模型,从而实现能适应用户兴趣变化的用户兴趣模型。 相似文献