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101.
Vehicle Teleoperation Interfaces 总被引:1,自引:1,他引:0
Despite advances in autonomy, there will always be a need for human involvement in vehicle teleoperation. In particular, tasks such as exploration, reconnaissance and surveillance will continue to require human supervision, if not guidance and direct control. Thus, it is critical that the operator interface be as efficient and as capable as possible. In this paper, we provide an overview of vehicle teleoperation and present a summary of interfaces currently in use. 相似文献
102.
研究了钴基非晶丝材料显示的应力电阻抗 (SI)效应。结果表明 ,淬态钴基非晶丝在其两端受到外加轴向压力作用下可呈现显著的应力电阻抗效应 ,它与驱动电流频率及幅值均有关 相似文献
103.
为了辅助医生更好地完成显微外科手术,开发了一种主从异构的显微外科手术机器人系统——“妙手”系统.“妙手”系统的主手为商业化的Phantom Desktop主手,从手为针对显微外科血管缝合而设计的“妙手”从手.从手包括位置机构和姿态机构.位置机构通过丝传动实现双四连杆机构的运动特性;姿态机构采用三轴交汇于一点的设计思想.通过分析双四连杆机构的运动特性,根据Angeles运动灵活度指标对双四连杆机构进行了优化.结果表明:当双四连杆机构前三级杆等长且I级杆与III级杆垂直时,机构运动灵活度取最大值. 相似文献
104.
Ride comfort optimization of a city bus is considered in this article, using stiffness and related damping of the power unit
mounts as design variables. The response of the bus, due to road irregularities, is calculated in the time domain by using
a finite element (FE) model describing the complete vehicle. The body of the bus is condensed, using a substructuring technique,
in order to reduce the simulation times. Operational deflection shapes (ODS) have been used to compare measured and calculated
vibrations and some corrections of the FE model have been done. The response, i.e. acceleration, at three locations in the
bus has been frequency-weighted according to the comfort standard ISO 2631:1997. The resulting root mean square (RMS) values
of these responses are then used in the objective functions in the optimization procedure. The computational results show
that it is possible to increase the ride comfort. However, the improvement of the ride comfort is probably too small to have
a substantial subjective impact on the passenger in the bus. The results show that the objective function, regarding the overall
ride comfort in the bus, has local optima.
Received October 10, 1999 相似文献
105.
服装压感舒适性评价主要有客观评价法、主观评价法和主客观综合评价法.客观评价法多是通过服装压的客观测量来体现的,服装压的客观测量分为间接测量与直接测量,直接测量因其测试方法简单被广泛应用.主观评价法由于能解决许多客观测量不能解决的问题,能比较公正地反映受试者的着装感受,也是服装压感舒适性评价的一种重要方法.但由于服装压感舒适性评价的复杂性,单独使用任何一种方法均不全面,只有将两种方法结合起来,采用主客观综合评价法才能更加完善地进行评价.同时,也指出了服装压感舒适性评价法的发展趋势及注意事项. 相似文献
106.
随着海洋平台上部结构的增大,大直径超长的钢管桩越来越多的被应用于实际工程中.要想对桩的可打入性进行准确预测,首先要对打桩冲击振动对周围土体所造成的影响有准确的评价.为了对打桩过程中的土阻力作出准确分析,根据渤海海域36根桩的打桩记录,对其中粘性土土层的打桩记录进行了反分析,总结了打桩过程中粘土层中土阻力的变化特点,分析了这些特点产生的原因.同时利用实测数据回归得到粘土层强度衰减的规律,提出了进行打桩分析时粘土层计算参数选取的方法,并通过一个实际工程对此进行了验证.分析结果显示,粘土层在打桩过程受动力效应的影响较大,其土性参数会随着捶击数的增加而降低,采用回归结果对打桩预测可以取得较好的结果. 相似文献
107.
108.
《Ergonomics》2012,55(9):1728-1744
The acceptance of a split keyboard with a user-adjustable angle (adjustable keyboard) and its impact on postural discomfort and general comfort of users was tested in a comparative laboratory experiment with 26 typists as subjects. The comparison was made with a standard keyboard. The results were interpreted using the findings of an earlier field study with another split keyboard with a fixed angle between the halves of the device. Both split keyboards improved postural comfort; however, the period of familiarization was much longer with the fixed-angle split keyboard. Since the adjustable keyboard allows a change, in the angle from 0 to 30°, a person's posture can be adopted on a step-by-step basis. Thus, the new adjustable design has much better prospects of being accepted in practice than former attempts where the value was more academic than practical. The analysis of throughput and errors, under self-determined angles of the test object and with an angle comparable with those of fixed-angle split keyboards, reveals that users in work situations are not likely to accept fixed-angle split keyboards (30°) since throughput is substantially reduced during the long period of familiarization, accompanied by a substantial increase in errors. The results of this study confirm the assumption that new adjustable split keyboard design, once accepted by the users, may improve postural comfort, general comfort, and reduce fatigue. These effects could be demonstrated both in a short-term experiment and a long-term field study. The basic design feature of the adjustable keyboard, adjustability, is in agreement with the conclusions of recent studies on the introduction of ergonomically designed keyboards. 相似文献
109.
《Ergonomics》2012,55(12):1795-1805
Due to typical physiological changes with age, older individuals are likely to have different perceptual responses to and different needs for driver–seat interface design. To assess this, a study was conducted in which a total of 22 younger and older participants completed six short-term driving sessions. Three subjective ratings (comfort, discomfort and overall) were obtained, along with 36 driver–seat interface pressure measures, and were used to assess differences and similarities between the two age groups. For both age groups, localised comfort ratings were more effective at distinguishing between driver seats and workspaces. Older individuals appeared to be less sensitive to discomfort than younger individuals. Across age groups, two distinct processes were used in determining whole-body comfort and discomfort perceptions based on localised comfort/discomfort perceptions. Whole-body discomfort levels were largely affected by lower back discomfort in the younger group versus upper back discomfort in the older group. Four specific pressure measures at several body regions differed between the age groups, suggesting distinct contract pressure requirements and loading patterns among these groups. 相似文献
110.
《Ergonomics》2012,55(8):1365-1371
We investigated the effectiveness of galvanic cutaneous stimulation (GCS) and auditory stimulation in mitigating simulator adaptation syndrome (SAS). Fifteen drivers (9 men; M age = 23.2 years) participated in a driving simulation experiment comparing three different stimulation conditions (GCS, auditory stimulation and no stimulation as a base line condition) in curves on a virtual urban circuit. GCS and auditory stimulation decreased SAS by reducing head sway. Both sources of stimulation can be recommended as countermeasures against SAS. We encourage the use of stimuli which influence the balancing ability to the design of future simulator protocols and devices to mitigate SAS. 相似文献