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61.
包装企业ERP系统构架分析   总被引:3,自引:3,他引:3  
孙德强  张宇  沈瑞 《包装工程》2004,25(4):213-214,219
文章首先提出包装企业ERP系统管理的核心问题--内部供应链管理,指出包装企业ERP系统的运行模式,并紧紧围绕供应链管理这一中心从包装企业的采购、销售、生产3方面的业务流程展开分析,涉及采购、库存、生产、销售、财务、人事、设备等部门和供应商及顾客共9类用户.最后由业务流程可得到各用户操作权限和操作功能,最终得到包装企业ERP系统构架.  相似文献   
62.
在版面分析过程中,有时会将表格误判为图形或将图形误判为表格。为避免对误判的表格或图形进行识别而产生的错误结果,文章提出了一种根据表格框线信息和表格单元信息来区分表格与图形的方法。该方法结合表格的结构特征,提出了作为一个表格的重要组成要素的表格框线和表格单元所必须满足的若干约束条件,通过验证每个条件是否得到满足来区分表格与图形。实验表明,该方法能有效地区分绝大多数表格与图形,极大地降低了对表格与图形的误判率。  相似文献   
63.
简析弯曲孔加工中的一些关键技术,介绍几种弯曲孔加工方法及其特点,着重说明基于线框电极的弯曲孔加工新工艺的原理、装置、影响因素和加工结果。  相似文献   
64.
《Soils and Foundations》2014,54(3):250-268
This paper presents a study of the influence of frame action on the response of buildings to deformations induced by deep excavations in soft clay. Using the finite element method, a building was modelled as a framed structure adjacent to a multi-propped excavation, firstly as a frame with continuous footings and then as a frame with individual footings. The geometry, location, and structural elements forming the frame models were varied to investigate the response of various frames. Using a structural analysis, parameters representing the stiffness of the frames in reducing deflection ratios and horizontal strains were derived. The influence of the frame action on the building stiffness can be quantified using the results from the finite element models. This makes it possible to estimate building modification factors from the relevant design charts so that induced deflection ratios and horizontal strains, caused by adjacent excavation and tunnelling activities, can be calculated. The approach gives a more realistic estimate of the tensile strains for assessing the potential damage caused to buildings.  相似文献   
65.
With the wide deployment of IEEE 802.11 Wireless Local Area Networks, it has become common for mobile nodes (MNs) to have multiple access points (APs) to associate with. With the Received Signal Strength Indicator (RSSI)-based AP selection algorithm, which is implemented in most commercial IEEE 802.11 clients, the AP with the best signal strength is selected regardless of the candidate AP’s available throughput, resulting in unbalanced distribution of clients among the APs in the network. Several studies have shown performance improvement in not just the new MN (nMN), but also the network as a whole when the selection process considers the current load status of candidate APs. However, the proposed algorithms in these studies assume that there are no hidden terminal problems that severely affect the performance of the network. Hidden terminal problems frequently occur in wireless networks with unlicensed frequencies, like IEEE 802.11 in the 2.4 GHz band. Moreover, none of the previous studies have considered frame aggregation, a major improvement in transmission efficiency introduced and widely deployed with the IEEE 802.11n standard. In this paper, we propose a new AP selection algorithm based on the estimation of available throughput calculated with a model based on the IEEE 802.11 distributed coordination function in consideration of hidden terminal problems and frame aggregation. The proposed algorithm is evaluated through extensive simulation, and the results show that the nMN with the proposed AP selection algorithm can achieve up to 55.84% and 22.31% higher throughput compared to the traditional RSSI-based approach and the selection algorithm solely based on the network load, respectively.  相似文献   
66.
沈杰  唐灵  周星 《电工钢》2019,1(1):48-54
通过对电工钢交流磁性检测方法现行国家标准(爱泼斯坦方圈法和标准单片法)在应用中存在的问题进行了梳理和解析,认为主要问题包括次级电压波形失真时需修正比总损耗、约定的有效磁路长度并非实际有效磁路长度以及磁性测量系统校准方法缺失等,并提出了采用数字反馈控制技术控制次级电压波形无需修正比总损耗、取向硅钢单片法测量时采用475 mm有效磁路长度以及磁性测量系统综合校准方案等一些解决方案。  相似文献   
67.
本文主要讲述在PKPM框架结构设计中注意的几个事项。从结构设计总说明各层布置图到基础平面图及详图几方面讲述。  相似文献   
68.
The overall aim of this study is to identify factors that influence architects' demotivation in design firms. After a review of extant literatures in design management, project management, and organisational behaviour, a list of 43 demotivating criteria was produced and used in a questionnaire survey. Analyses included reliability analysis, Mann–Whitney U and Kruskal–Wallis tests, demotivation severity index (DSI) computation and exploratory factor analysis. Results show an underlying factor structure of seven demotivating factors that include ‘organisational injustice’, ‘project induced stress’, ‘dysfunctional design team’, ‘poor interpersonal relationships’, ‘perceived career decline’, ‘negative leadership behaviours’ and ‘poor organisational culture’. Comparing these demotivational factors with motivational factors identified from previous related research, this study confirms that demotivation and motivation are on the same pole. In addition, what causes motivation or demotivation is a function of individual frame of reference. This implies that the presence or absence of a factor might cause motivation or demotivation depending on an individual frame of reference. Positive attention to the identified factors in relation to individual personality differences therefore helps to remove impediments that could affect employees' well-being such as being downcast, dispirited, depressed and despondent. The study would help directors and managers of design firms to develop a healthy workforce through recognition and eradication of the identified demotivating factors using some of the suggested solutions.  相似文献   
69.
通过对SP-160型开式压力机机身的受力进行有限元分析及计算,研究在公称压力下机身各部位的变形和应力分布,依此对机身结构进行优化设计。使用SolidWorks进行机身的有限元三维模型的创建,利用ANSYS和SolidWorks的接口直接导入ANSYS Workbench,对机身进行强度和刚度分析,根据分析结果在SolidWorks中完成机身三维模型结构的改进,从而达到减轻自重、降低成本的目的。  相似文献   
70.
In this paper, we study the impact of quantization, frame dropping and spatial down-sampling on the perceived quality of compressed video streams. Based on the analysis of quality ratings obtained from extensive subjective tests, we propose a no-reference metric (named MDVQM) for video quality estimation in the presence of both spatial and temporal quality impairments. The proposed metric is based on the per-pixel bitrate of the encoded stream and selected spatial and temporal activity measures extracted from the video content. All the values required to compute the proposed video quality metric can be obtained without using the original reference video which makes the metric for instance useful for making transcoding decisions in a wireless video transmission scenario. Different from comparable metrics in the literature, we have also considered the case when both frame rate and frame size are changed simultaneously. The validation results show that the proposed metric provides more accurate estimation of the video quality than the state of the art metrics.  相似文献   
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