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991.
Shameem Ahmed Moushumi Sharmin Sheikh I. Ahamed 《Universal Access in the Information Society》2008,7(4):273-283
Universal access from a handheld device (such as a PDA, cell phone) at any time or anywhere is now a reality. Ubicomp Assistant
(UA) (Sharmin et al. in Proceedings of the 21st annual ACM symposium on applied computing (ACM SAC 2006), Dijon, France, pp
1013–1017, 2006) is an integral service of MARKS (Sharmin et al. in Proceedings of the third international conference on information
technology: new generations (ITNG 2006), Las Vegas, Nevada, USA, pp 306–313, 2006). It is a middleware developed for handheld
devices, and has been designed to accommodate different types of users (e.g., education, healthcare, marketing, or business).
This customizable service employs the ubiquitous nature of current short range, low-power wireless connectivity and readily
available, low-cost lightweight mobile devices. These devices can reach other neighbouring devices using a free short-range
ad hoc network. To the best of the authors’ knowledge, the UA service is the only service designed for these devices. This
paper presents the details of Ubi-App, a ubiquitous application for universal access from any handheld device, which uses
UA as a service. The results of a usability test and performance evaluation of the prototype show that Ubi-App is useful,
easy to use, easy to install, and does not degrade the performance of the device. 相似文献
992.
An integrated, autonomous stick-on computing platform is proposed, consisting of (i) the Peer-it stick-on, multi-sensor, multi-actuator computer hardware, (ii) the Peer-it component-based software framework, and (iii) the Peer-it profile markup language PeerML, supporting spontaneous interaction among such platforms. The platform implements Peer-to-Peer computing principles in a self-contained, miniaturized, universal and scalable way, giving raise for application scenarios where the real-world artefacts like e.g. machines, tools or appliances–literally every thing–equipped with Peer-it technology can operate in spontaneously interacting, goal-oriented ensembles.Technically, preferences (like capabilities and goals) and context (like time, geo-position, owner, environmental conditions, etc.) of peers are kept as a profile encoded in PeerML in the local memory of Peer-its, and carried along wherever they move in space. Once peers come into spatial proximity of each other, profiles are exchanged via wireless communication, and the “similarity” of preferences is analyzed. In the case of “matching” preferences, an associated application is notified on both peers.Besides a fully functional autonomous hardware platform integrating multiple sensors, actuator arrays and wireless communication technologies, the Peer-it stick-on computer, a low-memory footprint, OSGi compliant Peer-it software framework has been implemented. We demonstrate in a flexible manufacturing systems (FMS) scenario, how the Peer-it technology can improve over centralized FMSs with respect to fault tolerance, scalability, flexibility in reconfiguration, productivity and efficiency. 相似文献
993.
Jürgen Bohn 《Personal and Ubiquitous Computing》2008,12(2):155-166
We provide evidence of the feasibility and effectiveness of a middleware architecture for mobile devices (MoDs), which employs
dense distributions of small computerized entities for providing fault-tolerant location-aware services. We do so by describing
exemplary implementations based on radio frequency identification as an enabling technology. Firstly, we present prototypical
implementations of the hardware abstraction layer and of selected core middleware services. The latter enable a MoD to store
and retrieve data and position information in physical places in a fault-tolerant manner, and to identify places based on
a location abstraction which is robust against failure of individual tags. Secondly, we investigate the feasibility of some
higher-level services and applications by developing and evaluating prototypical systems for tracing and tracking, self-positioning,
and collaborative map-making.
相似文献
Jürgen BohnEmail: |
994.
Eiman Kanjo Steve Benford Mark Paxton Alan Chamberlain Danae Stanton Fraser Dawn Woodgate David Crellin Adrain Woolard 《Personal and Ubiquitous Computing》2008,12(8):599-607
Mobile sensing and mapping applications are becoming more prevalent because sensing hardware is becoming more portable and
more affordable. However, most of the hardware uses small numbers of fixed sensors that report and share multiple sets of
environmental data which raises privacy concerns. Instead, these systems can be decentralized and managed by individuals in
their public and private spaces. This paper describes a robust system called MobGeoSens which enables individuals to monitor
their local environment (e.g. pollution and temperature) and their private spaces (e.g. activities and health) by using mobile
phones in their day to day life. The MobGeoSen is a combination of software components that facilitates the phone’s internal
sensing devices (e.g. microphone and camera) and external wireless sensors (e.g. data loggers and GPS receivers) for data
collection. It also adds a new dimension of spatial localization to the data collection process and provides the user with
both textual and spatial cartographic displays. While collecting the data, individuals can interactively add annotations and
photos which are automatically added and integrated in the visualization file/log. This makes it easy to visualize the data,
photos and annotations on a spatial and temporal visualization tool. In addition, the paper will present ways in which mobile
phones can be used as noise sensors using an on-device microphone. Finally, we present our experiences with school children
using the above mentioned system to measure their exposure to environmental pollution.
相似文献
Adrain WoolardEmail: |
995.
This paper presents a new parallel computing model, called H-BSP, which adds a hierarchical concept to the BSP(Bulk Synchronous Parallel) computing model. An H-BSP program consists of a number of BSP groups which are dynamically created at run time and executed in a hierarchical fashion. H-BSP allows algorithm designers to develop more efficient algorithms by utilizing processor locality in the program. Based on the distributed memory model, H-BSP provides a group-based programming paradigm and supports Divide & Conquer algorithms efficiently. This paper describes the structure of the H-BSP model, complexity analysis and some examples of H-BSP algorithm. Also presented is the performance characteristics of H-BSP algorithms based on the simulation analysis. Simulation results show that H-BSP takes advantages of processor locality and performs well in low bandwidth networks or in a constant-valence architecture such as 2-dimensional mesh. It is also proved that H-BSP can predict algorithm performance better than BSP, due to its locality-preserving nature. 相似文献
996.
In this paper we consider the potential of using an aggressive form of energy conservation for mobile computing environments. The estimators for the round-trip time and round-trip time variance used by TCP are used to direct the transceiver of a mobile node to idle over extended periods of time when packet activity is not anticipated. In addition, we consider data link layer extensions that provide additional control information allowing the mobile to be further selective as to when to idle and when to activate the network interface device. Simulations are conducted to examine the performance of the proposed scheme under various levels of congestion in the fixed part of the network, from completely unloaded to fully congested. The simulations reveal that the technique is promising but its effectiveness depends crucially on the control of the maximum window size used by TCP and on accurate knowledge of the congestion conditions in the network. 相似文献
997.
51.引言 在许多重要研究领域中,数值模拟相当复杂,数值模拟的结果依赖于数值方法的选取,计算网络的质量,边界处理等,其复杂性表现在物理特性、数学模型、计算区域不规则的几何形状等方面.当计算区域各部分的物理特性不同而且差异较大时,比如多种物质的流体运动流场中各个部分变化程度不均匀,有些部分变化非常平缓,有些部分变化极其剧烈;或者,当计算区域极其不规则时,比如空气动力学中的进气道系统的流场计算,绕复杂形状流场的数值分析等.若在计算区域上作整体计算,不仅难以准确地描述流场变化,而且受到计算机运算速度、… 相似文献
998.
999.
1000.
USB技术在可穿戴计算机中的应用 总被引:3,自引:0,他引:3
体积小、功能强、外国设备多、集成度高是可穿戴计算机的主要特点之一,由于可穿戴计算机对多媒体的要求很高,要实现的功能很多,以至于其外设种类很多,所以要求其接口种类也比较多,如串口、MCP接口、USB接口以及PCMCIA接口等等。若将这众多接口都集成在一起,不但设计复杂,而且集成后的体积仍然较大,且其扩充性也较低。USB接口则将这些不同的接口统一起来,使用一个4针插头作为标准插头,在可穿戴计算机的设计中采用USB接口作为主要的外设接口,可弥补上述的不足。重点介绍了可穿戴计算技术、USB技术并提出了一种将USB接口作为可穿戴计算机通用接口的设计方法。 相似文献