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1.
In this article, linear programming and fuzzy optimization models are developed for planning and management of available land-water-crop system of Mahanadi-Kathajodi delta in eastern India. The models are used to optimize the economic return, production and labour utilization, and to search the related cropping patterns and intensities with specified land, water, fertilizer and labour availability, and water use pattern constraints. Due to extreme backwardness of the study area, it has been decided to keep all the three objectives of the linear programming models at the same priority level to obtain the compromised solution in a fuzzy environment that incorporates the imprecision in fuzzy goals and fuzzy constraints. These non-structural models facilitate the conjunctive use of available surface water and groundwater resources. A comparative evaluation along with the benefit-cost ratios of the existing and proposed farming systems is also presented.  相似文献   
2.
Book review     
CLIMATIC FLUCTUATIONS AND WATER MANAGEMENT. by M. A. Abu‐Zeid and A. K. Biswas Butterworth Heinemann, Oxford, 1992, 356 pp, £50.00.  相似文献   
3.
Pole-like structures (PLSs) located in road environment are important roadway assets. They play a vital role in road safety inspection and road planning. The use of light detection and ranging (lidar) based mobile mapping technology for mapping of PLSs is an important area of research as it holds the potential for automation. Point cloud data of rural, peri-urban, and urban road environment are used in this study, which pose special challenge in view of the complexity of terrain, unlike well-planned roads, which have been the subject of interest in existing literature for identification of PLSs. A new five-step method is proposed in this article. The first two steps, i.e. ground filtering and voxelization of filtered non-ground points, are used for data size reduction. Next three steps are used to extract PLSs from reduced data. The proposed method was tested on point cloud data of three test sites having different levels of complexities. PLSs including partially occluded pole, tilted pole, pole situated very close to other objects, and vertical pole attached to tilted pole were accurately identified. Average correctness and completeness, respectively of 92.6% and 94.9%, were achieved in three different complex test sites, i.e. urban, peri-urban, and rural sites, respectively. Computation complexity shows that our proposed method delivers fast and computationally efficient solution for identifying the PLSs from volumetric mobile lidar point cloud. Impact of PLSs on road safety and road planning is also addressed for these selected test sites.  相似文献   
4.
Diode devices (glass/ITO/polymer/Al) have been fabricated using poly (3-hexylthiophene) (P3HT) crosslinked with two different biaryl crosslinkers. Crosslinking was performed by exposing the thin films with different wt% of crosslinker to UV irradiation and progress of crosslinking was monitored by IR spectroscopy. An increase in hole mobility of two orders of magnitude has been observed after crosslinking.  相似文献   
5.
This paper is based on a study conducted to assess and classify the Tanshui river in Taiwan, taking into consideration several relevant parameters. The classification was performed using a new approach. First, the current general uses of the river were assessed; classification was then made by river area, and the priority uses of each. Second, existing water quality was assessed using an indexing approach, specifically the River Pollution Index (RPI). This takes into account all relevant pollutant variables, eg DO, BOD, coliform count, etc, to determine the level of water quality at different reaches of the river. Finally, a classification of the Tanshui river based on its existing water quality and specific best usage was made.  相似文献   
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In decortication of wild apricot pit a mathematical model based on Hertz’s theory of contact stress was developed for the prediction of force required to break the pit. Using pits subjected to a uniaxial compression stress, in their lateral axis between rigid parallel plates, and those propelled to impinge a rigid cylindrical seat along its lateral axis, experimental verification of the model was conducted comparing the theoretical predictions with estimates from the representations of conventional methods employed in pit cracking. Properties including size, shape, and mass, required in the derived model were determined for wild apricot pits. Material stiffness was obtained from the force-deformation curve. Material stiffness obtained was 51.1 × 106 to 46.9 × 106 Nm-1 for different sizes of the pits (12, 11, 10, and <10 mm). The respective ranges of geometric mean diameters were between 16.92–15.05 mm. There was no significant variation of pit sphericity with size of pits. Force prediction from the Hertzian model proposed gave good prediction of cracking force that was not significantly different from that obtained from an impact force decorticator (1.2 kg weight reciprocating with 100 rpm and 30 cm stroke length) and compression force required calculated from a texture analyzer.  相似文献   
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Impact of long-term land application of biosolids on groundwater and soil quality of an application site, which had been operated for 8-15 years, was evaluated in this study. During and after the biosolids application, biosolids-amended soil, groundwater, and background soil samples were collected mainly for pathogen, nitrogen, phosphorus, and heavy metal analyses. Soil test data showed that there was no heavy metal accumulation in the biosolids-amended soil even after 10 years of biosolids application. Similar results were also observed from the groundwater samples in which the heavy metal concentrations in all groundwater samples were well below the maximum contamination levels of the drinking water standards. In addition, bacteriological levels of the soil and groundwater samples were close to the background level and below the permissible limits, respectively, thereby showing no pathogen contamination. However, nitrate-nitrogen contamination of the groundwater was occasionally observed probably due to an excess loading of the biosolids in the past. This problem can be alleviated by applying biosolids at agronomic rates so that no excess nitrogen is available for leaching down to the groundwater.  相似文献   
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