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51.
凃应宏 《武钢技术》2003,41(3):21-23,58
为了解决武钢三炼钢厂烟罩这类大型构件不便于在常规热处理炉内进行热处理的难题,根据有关工艺和标准要求对烟罩实施了整体炉外热处理,施工中采用在烟罩中段外部包扎保温材料,同时在烟罩两端搭设简易炉体的方法对烟罩进行保温,并制定相应的热处理施工工艺,对工件进行消除应力退火。退火后进行的应力测试表明,应用此种退火技术,工件的焊接残余应力的下降率可以达到60%以上,完全可以满足大型工件的消应力退火要求。  相似文献   
52.
Vapor–liquid equilibrium (VLE) at 101.3 kPa have been determined for a ternary system (tetrahydofuran + 2-propanol + 2,2,4-trimethylpentane) and its constituent binary systems (tetrahydrofuran + 2-propanol, tetrahydrofuran + 2,2,4-trimethylpentane, and 2-propanol + 2,2,4-trimethylpentane). The activity coefficients of liquid mixtures were calculated from the modified Raoult's law. Thermodynamic consistency tests were performed for all VLE data. The VLE data of the binary mixtures and ternary mixtures were correlated using the Margules, Wilson, NRTL, and UNIQUAC activity-coefficient models. The models with their best-fitted interaction parameters of the binary systems were used to predict the ternary vapor–liquid equilibrium. All VLE data are also used to calculate the reduced excess molar Gibbs free energy gE/RT and the deviations in the boiling point ΔT. The calculated quantities of gE/RT and ΔT were fitted to variable-degree polynomials in terms of liquid composition.  相似文献   
53.
Provision of automated support for planning protocol-directed therapy requires a computer program to take as input clinical data stored in an electronic patient-record system and to generate as output recommendations for therapeutic interventions and laboratory testing that are defined by applicable protocols. This paper presents a synthesis of research carried out at Stanford University to model the therapy-planning task and to demonstrate a component-based architecture for building protocol-based decision-support systems. We have constructed general-purpose software components that (1) interpret abstract protocol specifications to construct appropriate patient-specific treatment plans; (2) infer from time-stamped patient data higher-level, interval-based, abstract concepts; (3) perform time-oriented queries on a time-oriented patient database; and (4) allow acquisition and maintenance of protocol knowledge in a manner that facilitates efficient processing both by humans and by computers. We have implemented these components in a computer system known as EON. Each of the components has been developed, evaluated, and reported independently. We have evaluated the integration of the components as a composite architecture by implementing T-HELPER, a computer-based patient-record system that uses EON to offer advice regarding the management of patients who are following clinical trial protocols for AIDS or HIV infection. A test of the reuse of the software components in a different clinical domain demonstrated rapid development of a prototype application to support protocol-based care of patients who have breast cancer.  相似文献   
54.
A stability-indicating reversed-phase high performance liquid chromatographic method was developed for the detection of mitoxantrone HC1 and its degradation products under accelerated degradation conditions. The degradation kinetics of mitoxantrone HC1 in aqueous solution over a pH range of 1.18 to 7.20 and its stability in propylene glycol-or polyethylene glycol 400-based solutions were investigated. The observed rate constants were shown to follow apparent first-order kinetics in all cases. The pH-rate profile shows that maximum stability of mitoxantrone HC1 was obtained at pH 4.01. No general acid or base catalysis from acetate or phosphate buffer species was observed. The catalysis rate constants on the protonated mitoxantrone imposed by hydrogen ion water and hydroxy ion were determined to be 3.72 × 10 min-1 5.64 × 10-min-1 and 1.108 × 10-2min-1, respectively. The degradation rate constants of mitoxantrone affected by different ionic strength systems. Irradiation with 254 nm UV light at 25±0.5°C was found when canpared with the light-protected controls. Incorporation of nonaqueous propylene glycol or polyethylene glycol in the pH 4.01 mitoxantrone solution shows an increase in its stability at 502±0.5°C.  相似文献   
55.
Given the number of checking points, the speed of block motion estimation depends on how fast the block matching is. In this paper, a new framework, fine granularity successive elimination (FGSE), is proposed for fast optimal block matching in motion estimation. The FGSE features providing a sequence of nondecreasing fine-grained boundary levels to reject a checking point using as little computation as possible, where block complexity is utilized to determine the order of partitioning larger sub-blocks into smaller subblocks in the creation of the fine-grained boundary levels. It is shown that the well-known successive elimination algorithm (SEA) and multilevel successive elimination algorithm (MSEA) are just two special cases in the FGSE framework. Moreover, in view that two adjacent checking points (blocks) share most of the block pixels with just one pixel shifting horizontally or vertically, we develop a scheme to predict the rejection level for a candidate by exploiting the correlation of matching errors between two adjacent checking points. The resulting predictive FGSE algorithm can further reduce computation load by skipping some redundant boundary levels. Experimental results are presented to verify substantial computational savings of the proposed algorithm in comparison with the SEA/MSEA.  相似文献   
56.
AVO技术在寻找薄气层中的应用   总被引:3,自引:0,他引:3  
  相似文献   
57.
王娟  张建可 《真空与低温》1995,1(3):149-152
着重介绍了静态法测试低温下(-100~50℃)液体饱和蒸气压的原理及方法,给出了低温下液体全氟三乙胺饱和蒸气压的测试结果,并进行了讨论。  相似文献   
58.
文章针对广州强力安全部门网络安全系统防护提出的一种网络安全系统设计构架;对其中的网络安全体系结构设计与实现进行了详细的分析;提出了安全体系结构模型和管理执行策略模型,并详述了其设计过程。把安全体系结构、安全策略管理的实现和网络安全的实现机制有机地结合在一起。  相似文献   
59.
VCO非线性度检测是实现其非线性度精确校正的前提,研究VCO非线性度检测方法具有重要理论意义和实用价值。针对目前基于微元法和分数阶傅里叶变换的VCO非线性度检测方法在抗噪性、实时性等方面存在的不足,提出了一种基于重叠分段和分数阶傅里叶变换的VCO非线性度检测方法。所提方法采取重叠分段的策略以抑制噪声干扰,在分数阶傅里叶变换域进行幅度峰值搜索时改用收敛速度快的黄金分割法以增强实时性。仿真实验表明所提方法具有良好的抗噪性,分段重叠率为0.25时其检测的均方根误差约为现有方法的1/2;当重叠率小于2/3时,其实时性也优于现有方法。  相似文献   
60.

Due to the budget and environmental issues, adaptive energy efficiency receives a lot of attention these days, especially for cloud computing. In the previous research, we developed a combined methodology based on nonparametric prediction and convex optimization to produce proactive energy efficiency-oriented solution. In this work, the predictive analysis was further enhanced by deriving the mixture power spectral density to model the complex cloud monitoring statistics. By engaging the improved technique to the predictive analysis, the prediction process was more adaptive to handle the fluctuation in system utilization. As a consequence, the optimization process could subsequently produce more appropriate setting for energy savings. After the infrastructure setting has been made available, the instruction of virtual machine migration was created and implemented by the cloud orchestrator. This instruction condensed the services into the pool of active facilities, satisfying the objective of power efficiency. Eventually, any physical machine out of the power configuration would be gradually terminated. Compared to our former method, the effectiveness of the proposed technique has been proven by cutting down 4.92% of energy consumption, while still maintaining a similar quality of services.

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