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71.
A financial analysis of biomass briquetting technology in India has been undertaken. Simple cost functions for briquetting machines have been developed. Unit cost of briquette production for various types of raw materials and different capacities of briquetting units have been calculated. Role of different factors affecting the cost of production of briquettes have also been analysed. 相似文献
72.
Degradation due to electrical and optical stresses on organic semiconductor devices fabricated with imidazolin-5-one as an active layer is studied in this letter. It is found that while both electrical and optical stresses degrade device performance, the former leads to much faster degradation as compared with the latter. It is found that in electrical-stress degradation, the drop in current is a strong function of the charge flowing through the device during stress (charge fluence). For optical-stress degradation, it is strongly dependent on the duration of stress. It is also found that the input electrical and light energy during the stress may be annealing out some of the defects in the device and, hence, mitigating the degradation due to the applied stress. 相似文献
73.
74.
Usage pattern of clothes washing (and clothes washers) are strongly related to local cultural practices. Such practices have led to the development of distinctive clothes-washing technologies in the US, Europe, and Japan. In emerging markets such as China, several types of technologies often co-exist. Some use less energy but more water (the impeller type), and some use more energy but less water (the horizontal axis type). The competition between different technologies is thought to lead to better consumer choices. However, it could also lead to changes in clothes-washing habits—from cold to hot wash, and therefore to much higher energy use. This paper examines the standard development process in China to illustrate that adoption of foreign technologies and technical standards, if not carefully calibrated to the local cultural practices, could have unintended consequences for energy use and environment. 相似文献
75.
Many current approaches to software-implemented fault tolerance (SIFT) rely on process replication, which is often prohibitively expensive for practical use due to its high performance overhead and cost. The adaptive reconfigurable mobile objects of reliability (Armor) middleware architecture offers a scalable low-overhead way to provide high-dependability services to applications. It uses coordinated multithreaded processes to manage redundant resources across interconnected nodes, detect errors in user applications and infrastructural components, and provide failure recovery. The authors describe the experiences and lessons learned in deploying Armor in several diverse fields. 相似文献
76.
Devarakonda M.V. Iyer R.K. 《IEEE transactions on pattern analysis and machine intelligence》1989,15(12):1579-1586
A statistical approach is developed for predicting the CPU time, the file I/O, and the memory requirements of a program at the beginning of its life, given the identity of the program. Initially, statistical clustering is used to identify high-density regions of process resource usage. The identified regions form the states for building a state-transition model to characterize the resource usage of each program in its past executions. The prediction scheme uses the knowledge of the program's resource usage in its last execution together with its state-transition model to predict the resource usage in its next execution. The prediction scheme is shown to work using process resource-usage data collected from a VAX 11/780 running 4.3 BSD Unix. The results show that the predicted values correlate strongly with the actual; the coefficient of correlation between the predicted and actual values for CPU time is 0.84. The errors in prediction are mostly small and are heavily skewed toward small values 相似文献
77.
S. Iyer R. Parakkat B. Mangalam B. Patnaik M. Falvo N. Parikh 《Journal of Electronic Materials》1996,25(1):119-124
The effects of damages produced by implantation of Te, Er, Hg, and Pb ions into undoped (100) GaSb single crystals and their recovery by Rutherford backscattering (RBS)/channeling were investigated. The implantations with dosages in the range of 1013 to 1015 ions/cm2 were carried out at liquid nitrogen temperature, at energies corresponding to a projected range of 447Å in GaSb. Near surface damage equivalent to that of an amorphous layer was observed even at lower doses. The samples were annealed at 600°C for different durations, with the Te implanted sample of the lowest dosage exhibiting the best recovery (Χmin = 11%) compared to others. This value of Χmin nearly corresponds to that of the virgin crystal. Examination of the surface morphology as a function of mass, dosage, and annealing duration revealed that it was strongly influenced by the dosage of the implanted ions. 相似文献
78.
79.
We report a case of a 63-year-old woman who presented with pseudoaneurysm of the free wall of the left ventricle secondary to myocardial infarction, in the presence of angiographically normal major coronary arteries. This is the only such case we know of, in which the patient underwent successful surgical correction. At last follow-up, the patient was in good condition with no evidence of cardiac disease, at 9 years after surgery. 相似文献
80.