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81.
Collaborative business process can become unreliable when business partners collaborate in a peer- based fashion without central control. Therefore, reliability checking becomes an important issue that needs to be dealt with for any generic solution in managing business collaboration. In this paper, we propose a novel Choreographical Business Transaction Net (CoBTx-Net) to model collaborative business process and to manage the collaboration by individual participants. Furthermore three reliability properties named Time-embedded dead marking freeness, Inter-organizational dead marking freeness, and Collaborative soundness are defined based on CoBTx-Net to verify (1) the violation of time constraint, (2) collaborative logic conflicts, and (3) the improper termination from individual organizations.
Lai XuEmail:
  相似文献   
82.
Support vector machines (SVM) is an effective tool for building good credit scoring models. However, the performance of the model depends on its parameters’ setting. In this study, we use direct search method to optimize the SVM-based credit scoring model and compare it with other three parameters optimization methods, such as grid search, method based on design of experiment (DOE) and genetic algorithm (GA). Two real-world credit datasets are selected to demonstrate the effectiveness and feasibility of the method. The results show that the direct search method can find the effective model with high classification accuracy and good robustness and keep less dependency on the initial search space or point setting.  相似文献   
83.
This paper proposes a nonlinear generalization of the popular maximum-likelihood linear regression (MLLR) adaptation algorithm using kernel methods. The proposed method, called maximum penalized likelihood kernel regression adaptation (MPLKR), applies kernel regression with appropriate regularization to determine the affine model transform in a kernel-induced high-dimensional feature space. Although this is not the first attempt of applying kernel methods to conventional linear adaptation algorithms, unlike most of other kernelized adaptation methods such as kernel eigenvoice or kernel eigen-MLLR, MPLKR has the advantage that it is a convex optimization and its solution is always guaranteed to be globally optimal. In fact, the adapted Gaussian means can be obtained analytically by simply solving a system of linear equations. From the Bayesian perspective, MPLKR can also be considered as the kernel version of maximum a posteriori linear regression (MAPLR) adaptation. Supervised and unsupervised speaker adaptation using MPLKR were evaluated on the Resource Management and Wall Street Journal 5K tasks, respectively, achieving a word error rate reduction of 23.6% and 15.5% respectively over the speaker-independently model.  相似文献   
84.
The reaction between silicon carbide and aluminium to form silicon and Al4C3 in SiC particle-reinforced aluminium fabricated by liquid aluminium infiltration was most severe near the original interface between liquid aluminium and the SiC preform. This resulted in the highest concentration of Al4C3 and the lowest concentrations of silicon and SiC in the part of the composite near this interface. In particular, the silicon concentration was highest in the bottom centre of the composite when infiltration occurred from the top, because silicon diffused toward the surrounding aluminium melt before solidification. These non-uniform phase distributions, as measured by X-ray diffraction and differential scanning calorimetry, did not cause any non-uniform shear strength distribution. However, excessive reaction between SiC and aluminium, as observed for an infiltration (=mould=liquid metal) temperature of 780° C, caused the tensile strength to decrease. In the case where a steel mould was used during infiltration at 780° C, iron-containing precipitates, such as ternary Al-Fe-Si, were observed in the part of the composite within 5 mm from the above-mentioned interface; their formation was related to the silicon out-diffusion in the form of liquid Al-Si; they caused the shear strength to be lower in this part of the composite; larger such precipitates (up to 100 m) were observed in the excess aluminium adjacent to the cast composite. For pure aluminium as the infiltrating metal, the optimum infiltration temperature for the highest tensile strength was 700° C. An infiltration temperature of 670° C resulted in incomplete infiltration, which was more severe when a steel mould rather than a graphite mould was used because of the higher thermal conductivity of the former.  相似文献   
85.
RADIOIMMUNOTOXICOLOGICALEFFECTOFENRICHEDURANIUMONCENTRALANDPERIPHERALIMMUNECELLSANDTHEPROTECTIVEACTIONOFIL-1ANDIL-2¥ZhuShoupe...  相似文献   
86.
The instability of few‐layer black phosphorus (FL‐BP) hampers its further applications. Here, it can be demonstrated that the instability of FL‐BP can also be the advantage for application in biosensor. First, gold nanoparticle/FL‐BP (BP‐Au) hybrid is facilely synthesized by mixing Au precursor with FL‐BP. BP‐Au shows outstanding catalytic activity (K = 1120 s?1 g?1) and low activation energy (17.53 kJ mol?1) for reducing 4‐nitrophenol, which is attributed to the electron‐reservoir and electron‐donor properties of FL‐BP, and synergistic interaction of Au nanoparticles and FL‐BP. Oxidation of FL‐BP after catalytic reaction is further confirmed by transmission electron microscope, X‐ray photoelectron spectroscopy, and zeta potentials. Second, the catalytic activity of BP‐Au can be reversibly switched from “inactive” to “active” upon treatment with antibody and antigen in solution, thus providing a versatile platform for label‐free colorimetric detection of biomarkers. The sensor shows a wide detection range (1 pg mL?1 to –10 µg mL?1), high sensitivity (0.20 pg mL?1), and selectivity for detecting carcinoembryonic antigen (CEA). Finally, the biosensor has been used to detect CEA in colon and breast cancer clinical samples with satisfactory results. Therefore, the instability of BP can also be the advantage for application in detecting cancer biomarker in clinic.  相似文献   
87.
The microstructure and mechanical properties of Sn–xBi (x = 10, 20, 25, and 35) solder alloy were investigated by scanning electronic microscope and notch tensile test. The results showed that the microstructure of Sn–10Bi and Sn–20Bi solder alloy was constituted by Bi particle and β-Sn phase. The microstructure of Sn–25Bi and Sn–35Bi solder alloy was consisted of eutectic phase and primary phase. The ultimate tensile load of Sn–20Bi solder alloy was higher than that of Sn–10Bi in notch tensile test. The ultimate tensile load of Sn–25Bi and Sn–35Bi was declined gradually compared with that of Sn–20Bi solder alloy. The fracture energy of Sn–xBi was decreased continuously when the Bi fraction increased. Crack observation, fracture surface observation, and finite element analysis revealed that the crack initiation and propagation of Sn–25Bi and Sn–35Bi was dominated by the fracture of brittle eutectic phase. Therefore, the ultimate tensile load and fracture energy of Sn–25Bi and Sn–35Bi were damaged compared with that of Sn–20Bi.  相似文献   
88.
本文从管理要求与技术要求两个方面指出了实验室管理体系运行中常见的问题,并结合实际情况提出了相应措施,最后对加强实验室管理体系运行有效性提出了几点建议。  相似文献   
89.
本文引出了GPS姿态测量,介绍了GPS测量原理,根据GPS测量系统的特点分析了测量过程中的各种误差,并提出了相应的误差消除措施。  相似文献   
90.
ABSTRACT

A primary goal for human-autonomy integration (HAI) is to balance the strengths of human and autonomy in order to achieve performance objectives more efficiently and robustly than either the human or autonomous agents would independently. This paper proposes the Privileged Sensing Framework (PSF) as a novel approach to HAI. This approach is based on the concept of dynamically ‘privileging’ information during the process of integration by dynamically bestowing special rights based on the characteristics of each individual agent, the task context, and the performance goals. The proposed framework is tested through a series of simulation experiments that provide a clear demonstration of increased accuracy and throughput of human-autonomy performance. These proof-of-concept simulations provide initial evidence of the utility of the PSF. Continued development of this approach has the potential to revolutionise capabilities of multi-agent cooperative teams across a broad range of applications.  相似文献   
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