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排序方式: 共有1530条查询结果,搜索用时 31 毫秒
1.
一种枪械总体动态优化设计的新方法   总被引:1,自引:0,他引:1  
胡志刚  徐诚  郭凯 《兵工学报》2005,26(2):150-154
针对枪械产品的设计复杂性,结合多个学科领域优化的特点,提出应用多学科优化设计方法(MDO)来设计和优化武器产品.首先归纳分析了MDO方法,给出其在枪械设计过程中的应用框架,在此基础上开发了应用平台.最后给出了一个机枪的四个子系统两级优化模型的算例.说明在该平台上应用MDO方法于机枪的总体优化设计是可行的.  相似文献   
2.
Experimental results and a theoretical analysis are presented on structured packing liquid holdup under cryogenic conditions. The experimental tests were performed on a novel laboratory unit incorporating a gas lift pump to recirculate the cryogenic liquid in a flow visualization dewar. Holdup is measured by sensing the difference in level in the dewar when the liquid flow is shut off after a constant operation at a given liquid loading. A dimensional analysis is performed to identify the important system properties that affect the liquid holdup. The preliminary experimental data are compared against a correlation developed from the dimensional analysis.  相似文献   
3.
The filtration time, t(f), during constant pressure dead-end filtration testing of wastewater sludge is dependant on the initial height, h(0), and the initial solids concentration, phi(0). The theoretical dependencies of these initial conditions are explored: t(f) varies with h(0)(2) and cphi(0)(2), where c is a material dependant parameter that is also dependant on phi(0) and the applied pressure. Empirical values for c relative to a given phi(0) are determined from phenomenological filtration theory to give a qualitative scaling method to compare the filtration behaviour of highly compressible materials under differing initial conditions. The method is validated using filtration testing of municipal wastewater sludge. This new scaling method is applied to the filtration results of a range of different wastewater sludges, additives and treatments to illustrate its application for plant comparisons, polyelectrolyte comparisons, dose optimisation of polyelectrolyte and ferric chloride and combinations thereof, and the effects of two physicochemical treatments.  相似文献   
4.
紧凑式辊底连续热处理炉计算机优化控制   总被引:4,自引:0,他引:4  
以钢坯二维传热过程数学模型为基础,开发了紧凑式宽厚板辊底式连续热处理炉计算机优化控制系统。其功能主要包括:钢坯物料跟踪、钢坯温度跟踪、钢坯优化加热控制、钢坯连续及摆动运行控制、钢坯混装炉温优化控制、钢坯温度反馈控制等。采用PCS7控制系统在轧钢厂实现了辊底式热处理炉钢坯生产过程的在线优化控制和管理。经现场实际生产检验,系统运行稳定,模型准确可靠,温度跟踪最大误差1.47%,炉温优化设定值满足热处理工艺要求,热处理钢坯合格率达到98%以上。  相似文献   
5.
The aim of this work relates to the optimization of a cold formulation of a depilatory emulsion containing thioglycolate of calcium, which presents the same characteristics as a reference product. To lead to this objective, a cubic simplex method was used. A preliminary formulation was preformed to evaluate the influence of each factor on the process formulation. The depilatory creams carried out present a rheological behaviour described by the model of Hershell-Bulkely, whose parameters are considered as responses of the optimizing system. This strategy allows both reducing and optimizing the number of experiments. The rheological measurements and the tests of stability showed that the use of an emulsifying polymer led to obtain a stable depilatory cream with a good effectiveness at a strong pH value.  相似文献   
6.
Bracho N  Lloyd B  Aldana G 《Water research》2006,40(8):1677-1685
The present study was conducted with the aim of improving faecal coliform (FC) and faecal streptococcus (FS) removal efficiencies in tertiary maturation stages of a sewage treatment plant in Southern England, where climatic conditions are sub-optimal. The research used intensive field assessments (bacteriological, general quality and hydraulic) to identify the parameters that affect the bacteriological quality of the effluent from three parallel maturation ponds (North, Central and South) of similar geometry and dimensions. An engineering intervention was carried out to convert the South pond to three channels to increase the L/W ratio from 9:1 to 79:1. Hydraulic tracer studies in the South pond with Rhodamine WT showed that the dispersion number 'd' was reduced from 0.37 (dispersed flow) to 0.074 by this intervention under similar flow conditions (4.5l/s). Hydraulic retention time was thus increased by 5h, delay in jet flow short-circuiting was increased from 2.5 to 17.5h thus increasing the exposure times for all elements. As a result of the intervention FC removal increased substantially. Maximum channel-lagoon efficiency of 99.84% was obtained at 4.5l/s and 19 degrees C, when exposure to sunlight was 17 h in summer. It is concluded that the channel configuration produces a higher hydraulic efficiency than conventional maturation ponds. It is therefore recommended as a viable engineering solution which permits a low-cost upgrading of plant performance, requiring no additional land, and with minimal maintenance costs.  相似文献   
7.
Process modelling refers to the development of a process model that serves to provide the input-output relationship of a process, while process optimisation provides the optimum operating conditions of a process for a high-yield, low cost and robust operation. Normally, process modelling is a starting point of process optimisation. In this paper, a method of integrating artificial neural networks with a gradient search method for process modelling and optimisation is presented. Artificial neural networks are used to develop process models while a gradient search method is used in process optimisation. Application of the method to the modelling and optimisation of epoxy dispensing for microchip encapsulation is described. Results of the validation tests indicate that good quality of encapsulation can be obtained based on the proposed method.  相似文献   
8.
Predictive microbiology is mainly applied in the area of risk assessment, but unusually regarded as a tool for the optimisation of processes, which needs the implementation of food engineering. Combination of predictive microbiology and food engineering allows both the assessment of a process in relation to risk and its optimisation. Intrinsic comparison between processes in relation to risk, on one hand, and the development of process optimisation tools on the other hand, necessitates the implementation of new concepts and the involvement of simplified and standard calculations based upon reference target strains and environmental conditions. Some conventional concepts related to heat treatments are extended, while some new ones related to bacterial growth are derived from the gamma concept of Marcel Zwietering.  相似文献   
9.
Conceptual design of a satellite launch vehicle is a multidisciplinary task which must take into account interactions of disciplines such as propulsion, aerodynamics, structures, guidance and orbital mechanics. We discuss the initial modelling of a clean sheet design for a putative Australian medium launch vehicle capable of placing an Ariane-44L equivalent payload into geostationary transfer orbit. While the Ariane-44L vehicle design is a three and a half stage vehicle, the alternative design is for a straight three stage vehicle. The “ideal velocity” or delta-V capability of the AR44L is first derived from published data. The proposed design is then modeled using a spreadsheet. The gross lift-off weight of the vehicle is then minimised while still providing the same delta-V as Ariane. Various differences between the two vehicles are discussed. The initial design of a launch vehicle as presented here is based on a simple stack model optimised automatically using an evolutionary algorithm. The efficiency of the proposed approach and the reasons for using evolutionary algorithms is discussed along with future developments in the areas of multi-objective formulations of the design optimisation problem as well as the vehicle model from the standpoint of a number of system considerations.  相似文献   
10.
Business Capabilities as configuration elements of value added networks   总被引:1,自引:1,他引:0  
The ubiquitous globalization, which opens up new markets, often with local content requirements and different labor cost levels, forces enterprises to organize their added value within global networks. The tendency to concentrate on the companies’ core competences challenges the companies further not only to organize their different sites but also to consider their partners and suppliers. The emerging value added networks have to be configured, operated, optimized and dynamically reconfigured. This article presents an approach for the configuration and evaluation of these value added networks based on Business Capabilities and Value Added Modules. Therefore the needed Business Capabilities to achieve the intended added value are matched with the Business Capabilities provided by the different nodes of the network and different network alternatives are developed and assessed to find efficient configurations.  相似文献   
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