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111.
用国产SLHP001短程纺牵联合机和SLHP 101丝束加工联合机,通过选择合理生产工艺,着眼于提高纤维的刚性和膨松性,研制出了高质量的烟用聚丙烯丝束。不加胶粘剂成型的滤棒(120mm),圆周稳定,硬度达到88%—89.5%,吸阻为3.2-3.4kPa,产出率达到125万支/t,比国内同类产品高15—20万支/t。 相似文献
112.
构造了新的区间犹豫模糊熵、交叉熵公式,提出了一种新的区间犹豫模糊多属性群决策方法,并将其应用于地方高等教育发展研究的过程中。构建了一种新的区间犹豫模糊熵公式,并证明其满足区间犹豫模糊熵的公理化条件;给出了区间犹豫模糊距离测度的公理性定义,研究了区间犹豫模糊距离测度和区间犹豫模糊熵、交叉熵的关系,并构建了区间犹豫模糊加权交叉熵公式。在区间犹豫模糊环境下,基于区间犹豫模糊熵、交叉熵以及交叉熵贴近度,提出了一种新的属性权重未知的多属性决策方法,并将其应用于对地方高等教育发展研究的过程中,验证该方法的可行性和有效性。 相似文献
113.
我国二氧化硫氧化制硫酸的钒催化剂现状和展望 总被引:2,自引:0,他引:2
陈学梅 《硫磷设计与粉体工程》2004,(4):12-16
从钒催化剂的生产、市场、开发、质量等方面分析我国二氧化硫氧化制硫酸催化剂的现状,指出我国钒催化剂与国外产品存在的差距和原因,提出发展钒催化剂的对策。 相似文献
114.
Failure mode and effects analysis (FMEA) has shown its effectiveness in examining potential failures in products, process, designs or services and has been extensively used for safety and reliability analysis in a wide range of industries. However, its approach to prioritise failure modes through a crisp risk priority number (RPN) has been criticised as having several shortcomings. The aim of this paper is to develop an efficient and comprehensive risk assessment methodology using intuitionistic fuzzy hybrid weighted Euclidean distance (IFHWED) operator to overcome the limitations and improve the effectiveness of the traditional FMEA. The diversified and uncertain assessments given by FMEA team members are treated as linguistic terms expressed in intuitionistic fuzzy numbers (IFNs). Intuitionistic fuzzy weighted averaging (IFWA) operator is used to aggregate the FMEA team members’ individual assessments into a group assessment. IFHWED operator is applied thereafter to the prioritisation and selection of failure modes. Particularly, both subjective and objective weights of risk factors are considered during the risk evaluation process. A numerical example for risk assessment is given to illustrate the proposed method finally. 相似文献
115.
This paper presents a novel pattern matching technique that is robust to illumination changes and the occlusion problem. The technique is based on the matching of gradient orientations in place of traditional image features such as intensities or gradients. Gradient orientations depend on the texture in an image. They are known to be insensitive to changes of image intensities that are often caused by time-varying illuminations or the auto-gain control (AGC) function of the camera. Moreover,the proposed method employs a voting strategy in the process of matching gradient orientations. The method works remarkably well even when a large part of the pattern is occluded with a foreign object. Consequently, the proposed method is robust to both irregular lighting conditions and the occlusion problem. 相似文献
116.
117.
提出了一种基于距离变换、形态重构和分水岭算法的图像分割算法。将一幅图像通过距离变换得到距离灰度图,与形态重构算法结合,得到颗粒图像的标识点图,用标识点图对距离灰度图进行分割,再用分水岭变换对分割后的距离灰度图进行变换。试验表明,该算法能有效合理地解决粘连或者重叠颗粒等物体的分割。 相似文献
118.
水流充分掺气可以避免高流速泄洪设施发生空蚀,但也会改变相关水力特性。通过对某大坝泄洪洞掺气设施水力模型试验及关于水流表面自掺气发生条件的相关分析,提出了在全程流速超过38 m/s,长度达550 m的明流洞内仅布置一级掺气设施的建议,较通常情况减少了两级;并针对泄洪洞出流方向与河道流向交角达60°的特点,研究提出了一种大差动异型鼻坎消能工。水工模型试验成果表明,其挑流水舌沿河道纵向扩散良好,水舌外缘与河道对岸保持了30 m以上的安全距离。该泄洪洞建成后经历了高水头、较长时间的泄洪运行,明流洞和鼻坎消能工均无空蚀发生,但挑坎水舌却冲刷到对岸边坡。 相似文献
119.
《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
120.