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151.
基于触摸屏的分布式伺服控制系统研究 总被引:2,自引:1,他引:2
传统的生产和检修设备大多采用继电器控制,操作复杂、故障点多、可靠性及可信度低、设计周期长、投资回收慢。与此同时随着自动化领域对人机界面要求的提高,触摸屏在这领域得到越来越广泛的应用。论文以现场总线控制系统理论和触摸屏幕应用理论为基础,介绍了一种基于RS232通讯协议的HITECH触摸屏与分布式控制系统的通讯方法,采用现场总线控制系统的设计思想,设计并实现了一个基于PWS6600、CAN总线和以太网的多电机的伺服控制系统。 相似文献
152.
大学学科课程研究性教学模式的构建 总被引:4,自引:0,他引:4
大学学科课程研究性教学模式主要适用于专业核心课程的教学。它的核心理念是人本教学理念、权变中心理念、主体有序互动理念和发展性能力养成理念 ;主要方式是基本知识与经典理论交往式教学、课题研究汇报教学和课题研讨评点教学 ;目标指向是学生的发展性能力养成。 相似文献
153.
高新技术企业薪酬体系设计原则分析 总被引:1,自引:0,他引:1
高新技术企业区别于传统企业的特殊性 ,决定了其激励—约束机制需要在很大程度上进行创新 ,所以传统的一些薪酬制度已经不适合高新技术企业的发展。本文首先探讨了高新技术企业本身及其人才的特点 ;然后在此基础上阐述了高新技术企业在薪酬体系设置的过程中应注意的三个原则 :股权激励性、阶段性和多重性 相似文献
154.
Effects of human activities on benthic macroinvertebrate community composition and water quality in the upper catchment of the Mara River Basin,Kenya
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Zipporah Gichana Murithi Njiru Phillip Okoth Raburu Frank Onderi Masese 《Lakes & Reservoirs: Research and Management》2015,20(2):128-137
Land‐use changes in the upper reaches of the Mara River Basin have modified their biophysical and hydrological processes, resulting in water quality degradation in streams. This study was conducted to investigate the effects of human activities on water quality and macroinvertebrates along the Nyangores River, one of the main tributaries of the Mara River, Kenya. Seven sampling sites were chosen to correspond to the loss of riparian cover, livestock watering and human activities (e.g. laundry washing, bathing, cultivation, wastewater inputs, dumping of solid wastes from urban areas and settlements along the river). Physical–chemical variables and water samples for nutrient analyses were collected monthly from February to July 2012. Benthic macroinvertebrates also were collected at the same sites as for the water quality samples. Two‐way analysis of variance tested the significant differences for each variable among the sites. Similarity percentages (SIMPER) analysis was used to identify the key taxa contributing to differences between minimally disturbed and most disturbed conditions in the study area. The results indicated increased nutrient concentrations in agricultural and settlement areas. Significant (P < 0.05) spatial–temporal variations in water quality variables were observed. A total of 42 macroinvertebrate genera were encountered, with Ephemeroptera, Plecoptera and Trichoptera orders dominating the minimally disturbed areas, and Diptera dominating the disturbed areas receiving point and no‐point solid and liquid wastes, including nutrients, from urban areas and settlements. Canonical correspondence analysis (CCA) revealed significant relationships between macroinvertebrate communities and measured physicochemical variables. The results of this study indicate the need for protection of riparian zones and treatment of sewerage wastes before their release into waterways. The dumping of solid wastes near streams and rivers also is discouraged, to maintain the quality of surface waters and aquatic organisms. 相似文献
155.
General interest for robotic technology has been increased by the public and the media after Fukushima Daiichi Nuclear Power Plant (hereafter referred to as 1F) disaster. Especially, robots which can work under the very severe condition where personnel cannot access have demands for development. As to respond to such high demands, NEDO established ‘Disaster response unmanned systems development project’ in 2012.[1] This project is specialized in the development of various remote-controlled equipment, such as remote-controlled platform truck and remote control human interface under ‘Mobile Robot Development’. Remote-controlled platform truck is designed to safely and surely deliver robots and supplies, instead of using stairs and elevator, etc. in and out of building where it is too critical for personnel to work under. Remote control human interface for robots is designed to standardize the command and operation screen for operator, based on opinions from project members, and manned facility construction.[2] In this article, mechanical structure and development tasks for remote-controlled platform truck, and commonalization approach for operation and camera display of various remote-controlled equipment and robot for remote control human interface are stated. Background: due to hydrogen explosion triggered by The Great East Japan Earthquake on 11 March 2011, a reactor building at Fukushima Daiichi Nuclear Power Plant was severely damaged. It is required to reduce high radiation dose in the atmosphere of the reactor building to perform restoration. To pursue decontamination of the reactor building, equipment to lift and carry decontamination devices to upper floor are required. 相似文献
156.
Color quantization is a common image processing technique where full color images are to be displayed using a limited palette of colors. The choice of a good palette is crucial as it directly determines the quality of the resulting image. Standard quantization approaches aim to minimize the mean squared error (MSE) between the original and the quantized image, which does not correspond well to how humans perceive the image differences. In this article, we introduce a color quantization algorithm that hybridizes an optimization scheme based with an image quality metric that mimics the human visual system. Rather than minimizing the MSE, its objective is to maximize the image fidelity as evaluated by S‐CIELAB, an image quality metric that has been shown to work well for various image processing tasks. In particular, we employ a variant of simulated annealing with the objective function describing the S‐CIELAB image quality of the quantized image compared with its original. Experimental results based on a set of standard images demonstrate the superiority of our approach in terms of achieved image quality. 相似文献
157.
基于运动数据的动作识别技术是当今计算机视觉和模式识别研究领域的热点问题,然而根据动作识别结果进行人体情绪提取的研究却较少。为此,在现有人体行为学研究的基础上,结合计算机图形学、人工智能和机器学习等技术,得出一套关于人体情绪的数据集合,包括开心、愤怒、悲伤、恐惧4种基本情绪和惊喜、厌恶2种衍生情绪。从动作的角度分析这6种情绪得到动作,即情绪关系,按照动作识别的划分基准,将Period作为情绪提取的最小单位,确定单个Period的情绪列表,再结合动作和速率的参数,提取出在执行该动作时人体的情绪。实验结果表明,该方法能够有效地从3D运动数据中提取情绪信息。 相似文献
158.
针对传统WANO人误研究工作效率低下,流程混乱的特征,研究从WANO人误研究工作实际需求出发,采用面向对象技术设计,实现了一个基于信息系统的WANO人误研究平台.从平台构建的角度阐述了WANO人误研究平台的功能结构、平台框架、WANO人误数据库构建等技术要点,并介绍了平台在WANO人误数据ETL方面的应用效果. 相似文献
159.
Jong‐Ju Hong Seungjun Shin Woo‐Jin Song Kyung Joon Kwon Seong Gyun Kim 《Journal of the Society for Information Display》2016,24(1):44-56
The impression of quality of images can be enhanced on a high dynamic range (HDR) displays. Generally, a conventional 8‐bit image can be processed to an HDR image by inverse tone mapping operators. Among the operators, brightness discrimination mapping by applying brightness adaptation model attempted to mimic the human visual system. In this paper, we use a brightness adaptation model to derive a brightness discrimination mapping algorithm for HDR displays. The proposed algorithm maximizes a function, which represents the local and global brightness discrimination range by exploiting characteristics of the human visual system. Enhancement of details is verified by visualizing HDR images from dark to bright regions. Improvement of dynamic range is quantified by measuring increased discrimination ratio. 相似文献
160.
基于人机交互的实际应用场景,提出了一种交互目标声源三维定位与语音增强算法。该算法首先在广义相关法的基础上提出一种声达时延差的估计方法,通过由6个麦克风构成的平行均匀线阵接收模型,实现对目标声源的三维定位;然后在交互目标声源定位的基础上,通过调整时延波束叠加的权值,实现对目标语音的增强。仿真实验结果表明,文中提出的算法能够准确定位目标声源并对目标语音进行有效增强。在信噪比大于1.5 dB 的环境中,该算法可使目标声源达到98%以上定位精度,5 dB 以上信噪比改善,同时算法运算量小且易于硬件实现。 相似文献