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91.
Technology of constructing blast-filled dams and geotechnical properties of soils of such structures
G. I. Pokrovskii N. P. Lushnov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(7):395-400
1. | The use of collapse blasting for constructing rock dams substantially increases the technical and economic indices of the blasting technology of constructing earth dams. |
2. | The selection of the technology of constructing blast-filled dams is determined mainly by the engineering-geological conditions at the construction site. At present it cannot be confirmed whether the use of loosening blasting promotes an increase of the geological properties of soils forming the body of blast-filled dams. |
3. | Further investigations of the process of movement of blasted rock down a mountain slope with determination of the volume of moving rock, time, andvelocity (acceleration) for a known degree of slope roughness are required for a more complete comparison of the effectiveness of the two existing technologies of constructing dams by directional blasting. Such investigations also enable determining the possibility of using the Amontons-Coulomb law of friction for describing the movement of large earth masses. |
92.
A. F. Dmitriev A. I. Tyshenko N. N. Khlapuk 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(5):306-310
1. | It is necessary to correlate the value of the noneroding velocity with the time of flood passage. If canals are planned in regions where comparatively brief summer floods are dominant, the value of the noneroding velocity should be taken equal to 3 m/sec since by the start of the flood the grass cover will have time to develop and reach maximum strength. If the canals are to be constructed in regions where spring floods are dominant, for example, in the northwestern regions of the country, then the noneroding velocity should be taken equal to 1.5 m/sec, since by the start of the flood the grass carpet does not have time to develop and become stronger. |
2. | In the absence of a constant runoff in the canal, for example, drainage canals, it is necessary to revet the bottom and side slopes with grass carpets. |
3. | In the presence of a constant moistening is made from traditional materials, in the zone of alternate moistening and above it, it is necessary to revet the slopes within reinforced grass carpet. |
4. | In a hydraulic calculation of canals with revetment of the bottom and side slopes with grass carpet, it is necessary to determine the roughness coefficient from the graph of n=f(VR, i). In a hydraulic calculation of wide overgrown channels and in calculation of the movement of the flow over floodplain stretches of rivers free from shrubs and trees, it is necessary to determine the roughness coefficient from the graph of n=f(Vh, i). |
5. | Calculation of canals with nonuniform roughness (rigid revetment and revetment by grass carpets) must be carried out on the basis of relations of uniform flow by means of a generalized roughness coefficient. |
93.
I. E. Mikhailov Yu. V. Polikarpov A. K. Fink 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(11):724-727
1. | The installation of a conical transitional segment between a tower (shaft)-type water intake-outlet and penstock affects a significant reduction in head loss in the pump mode, but has virtually no effect on the magnitude of the latter in the pump mode. |
2. | The existence of a conical transitional element in the pump mode appreciably lowers the discharge velocities of the flow and increases the effective height of the water-passing openings by 1.5–1.7 times when the height of the intake openings h0.5dp. |
3. | The head losses in the intake-outlet decrease in the pump mode of operation with increasing degree of expansion of the transitional diffusor segment. |
94.
95.
V. I. Koptev Yu. M. Gorshkov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1986,20(7):411-416
Conclusion The proposed method of detecting local defects in a cutoff curtain has a large radius of investigation and allows testing a 30-m-long section of the curtain during one experiment.Each experiment takes about 4 h. The area of use is limited to an evaluation of the quality of grout curtains constructed below the groundwater level. The method is intended for use together with other existing methods for increasing the details of checking grout curtains.In addition to a qualitative solution of the quality control problem (detection of local defects in the grout curtain), the method makes it possible to obtain a quantitative evaluation of the achieved effect based on solving the problem of the relation between the measured parameter
and effect of grouting
obtained for a homogeneous (porous) medium.The use of the described geophysical method of checking the quality of grout curtains makes it possible to increase the reliability of their work and to promptly introduce necessary changes into the grouting technology.Translated from Gidrotekhnickeskoe Stroitel'stvo, No. 7, pp. 23–27, July, 1986. 相似文献
96.
The aim of the paper is to examine the effects on employment of the large-scale structural adjustment programme undertaken by Turkey from the early 1980s onwards. In this respect, we particularly analyse how appropriate the choices of factor intensity after structural adjustment programme have been in the domestic production in comparison with the availability of domestic factor endowment. Our findings show that foreign trade in intermediate goods creates extra use of domestic labour, which can be considered as the labour cost of importing intermediate goods. This is the case in the majority of industries in the pre- and post-liberalisation period in Turkey. However, the capacity of using extra labour as a result of importing intermediate goods appeared to have decreased in the post-liberalisation period. 相似文献
97.
This paper focuses on: (1) how a select set of financial and economic factors could set the path for interest rates and foreign exchange rates, and (2) whether the resultant realized interest and exchange rates would be in harmony or in disarray. Using post-euro data for the EU and the US, an array of monetary rules is examined. In particular, the paper investigates whether the original and the extended Taylor rules provide an explanation of the dynamics of the EU monetary system since the inception of the euro. Our findings indicate that the EU and the US monetary responses are not the same and that exchange rates play a significant role. 相似文献
98.
This paper reports on a study to compare self-reports during an interview with staff who attended a University health centre in Turkey, with the records of visits to the same health centre over the previous 12 months. Design of the study reflects the effects of importance of the event, duration since the event, frequency of the occurrence of the event, measurement scale of the event, and bounded and unbounded recalling. In order to assess the extent of recall error, responses to retrospective questions on health centre visits are compared with administrative records. Statistical models are proposed for short and long term human memory recall error effects on responses. 相似文献
99.
Remaining life estimation of used components in consumer products: Life cycle data analysis by Weibull and artificial neural networks 总被引:1,自引:1,他引:1
Environmental awareness and legislative pressures have made manufacturers responsible for the take-back and end-of-life treatment of their products. To competitively exploit these products, one option is to incorporate used components in “new” or remanufactured products. However, this option is partly limited by a firm's ability to assess the reliability of used components. A comprehensive two-step approach is proposed. The first stage phase statistically analyzes the behavior of components for reuse. A well-known reliability assessment method, the Weibull analysis, is applied to the time-to-failure data to assess the mean life of components. In the second phase, the degradation and condition monitoring data are analyzed by developing an artificial neural network (ANN) model. The advantages of this approach over traditional approaches employing multiple regression analysis are highlighted with empirical data from a consumer product. Finally, the Weibull analysis and the ANN model are then integrated to assess the remaining useful life of components for reuse. This is a critical advance in sustainable management of supply chains since it allows for a better understanding of not only service requirements of product, but the remaining life in a product and hence its suitability for reuse or remanufacture. Future work should assess: (1) reduction in downtime of process equipment through the implementation of this technique as a means to better manage preventative maintenance; (2) reduce field failure of remanufactured product; (3) selling-service strategy through implementation of the proposed methodology. 相似文献
100.