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71.
Pashmina, a finest natural animal fiber is utilized for preparation of world famous Kashmiri pashmina shawls by traditional practices. Hand spinning is one of the important processing step, wherein fibers are converted into a fine yarn on a traditional spinning wheel (yander). The task is usually carried out by women folk. It is a laborious process resulting in a lot of physical stress affecting the efficiency of artisans. An innovative charkha has been fabricated to reduce the physical stress and its effect on the spinning efficiency and remuneration of artisans over traditional one was evaluated. The study revealed that innovative charkha was efficient in terms of time consumed for spinning by 73.50% over traditional one besides decreasing physical drudgery. In terms of income, there was an increase of 146% over traditional one for same period of time without deteriorating the quality of yarn. 相似文献
72.
The roles of hybrid-π, two-port, and SPICE transistor parameter are compared. A step-by-step procedure is described for determining numerical parameter values for a dynamic SPICE model of a bipolar junction from transistor manufacturer's measured data. The procedure is illustrated with an example 相似文献
73.
O.P. Malik G.S. Hope M.A.H. Sheirah 《International Journal of Electrical Power & Energy Systems》1983,5(3):159-165
The processing capability of computers makes it feasible to implement sophisticated techniques for process control. However, to minimize the software development costs, it is desirable to develop algorithms that can have a wider application. In keeping with this, an AVR and speed governor for a generating unit have been designed using the same algorithm, called the selftuning regulator. The selftuning AVR and speed governor have been implemented using a microprocessor and a minicomputer online. The feasibility of developing unified algorithms is demonstrated by means of realtime tests, in which the two controllers are used simultaneously for a generating unit physical model. 相似文献
74.
O.P. Malik G.S. Hope Ju M. Gorski V.A. Ushakov 《International Journal of Electrical Power & Energy Systems》1983,5(1):61-71
Results of experimental tests carried out with microprocessor-based voltage and speed regulators using a digital-analogue-physical model complex of a large power system at the Siberian Power Institute of the USSR Academy of Sciences are described. The physical test facility, and the test objectives and procedures are also outlined. Tests were carried out on a Soviet-built microprocessor AVR and a Canadian-built microprocessor AVR and speed governor. The work described shows that the development of speed and voltage regulators using microprocessors is a feasible and promising proposition. 相似文献
75.
Artificial neural networks can be used as intelligent controllers to control non-linear, dynamic systems through learning, which can easily accommodate the non-linearities and time dependencies. However, they require large training time and large number of neurons to deal with complex problems. Taking benefit of the characteristics of a Generalized Neuron that requires much smaller training data and shorter training time, a Generalized Neuron-Based Power System Stabilizer (GNPSS) and an adaptive version of the same have been developed. The objective of this paper is to compare the performance of the GNPSS with that of an adaptive version, the weights of which are updated on-line. 相似文献
76.
E Malik W B?hm F Stoz CD Nitsch WG Rossmanith 《Canadian Metallurgical Quarterly》1998,12(11):1326-1333
BACKGROUND: Laparoscopy can be used with minimal operative morbidity to evaluate adnexal masses. We report our experience with the endoscopic approach to the diagnosis and treatment of ovarian tumors. In particular, we describe 11 patients who incidentally underwent laparoscopy and in whom the ovarian masses were found to be malignant. METHODS: Between September 1994 and September 1996, 292 patients with 316 ovarian tumors were treated laparoscopically in the Department of Obstetrics-Gynaecology, University of Ulm. We assessed vaginal ultrasonography, clinical assessment, the tumor marker CA 12-5, and the intraoperative low-power magnification for their value in predicting the final diagnosis in all laparoscopically treated ovarian tumors. RESULTS: From a total of 292 patients with ovarian tumors, 11 were diagnosed, intraoperatively or after final histologic examination, as having a malignant or borderline ovarian tumor. All applied pre- and intraoperative diagnostic procedures were by themselves too unreliable to exclude early stages of ovarian carcinoma exactly. CONCLUSIONS: On the basis of the present findings, we are tempted to conclude that laparoscopic surgery is justified in the management of ovarian tumors. Even with an accurate preoperative selection of suitable patients for laparoscopic surgery, the presence of an undetected ovarian carcinoma cannot be entirely excluded. 相似文献
77.
GM Malik 《Canadian Metallurgical Quarterly》1998,59(3):397-398
In a retrospective case-control study of 58 cases of human brucellosis, adjusted mean serum calcium levels were found to be significantly higher in patients with brucellosis compared with controls: mean (95% confidence interval) = 2.39 (2.35-2.42) mmol/L versus 2.30 (2.26-2.34) mmol/L (P = 0.0012). The possible mechanisms underlying the cause of hypercalcemia in human brucellosis are discussed. 相似文献
78.
79.
We study the problem of how to minimize the cost of maintaining consistency among at least N copies of an object in an enviroment where the mix of read and write operations can vary. Quorum consensus requires that
read and write operations must assemble appropriate quorums before an operation can succeed. The cost of an operation is proportional
to the size of a quorum, and the objective is obviously to minimize the cost while still maintaining consistency. It is known
that the quorum size can be reduced by organizing a number of copies into logical structures such as grids and hierarchies.
In this paper, we show (a) how methods based on grids and hierarchies can be treated in a common framework, and (b) how these
hierarchies can be optimized so as to minimize the cost of consensus. Of course, the optimal solution depends upon the mix
of read and write operations that is present. Consequently, given N copies of an object and a ratio of write operations F, our algorithms determine the optimal values for the number of levels
in the hierarchy and the read/write quorum sizes at each level. The algorithms, which run in O(N
1.63) and O(N
2) time, were tested, and the results are reported and discussed.
Received September 1, 1992/February 16, 1995 相似文献
80.
Dye removal from wastewater using activated carbon developed from sawdust: adsorption equilibrium and kinetics 总被引:13,自引:0,他引:13
Malik PK 《Journal of hazardous materials》2004,113(1-3):81-88
Mahogany sawdust was used to develop an effective carbon adsorbent. This adsorbent was employed for the removal of direct dyes from spent textile dyeing wastewater. The experimental data were analysed by the Langmuir and Freundlich models of adsorption. Equilibrium data fitted well with the Langmuir model. The rates of adsorption were found to conform to the pseudo-second-order kinetics with good correlation. The equilibrium adsorption capacity of the sawdust carbon was determined with the Langmuir equation as well as the pseudo-second-order rate equation and found to be >300 mg dye per gram of the adsorbent. The most ideal pH for adsorption of direct dyes onto sawdust carbon was found to be 3 and below. The results indicate that the Mahogany sawdust carbon could be employed as a low cost alternative to commercial activated carbon in the removal of dyes from wastewater. 相似文献