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111.
Abdrabbo A. Abou Kheira 《Water Resources Management》2009,23(11):2317-2342
The Egyptian Ministry of Water Resources and Irrigation (MWRI) has expressed concern about the current high cost of the Irrigation Improvement Project (IIP) implemented in the “old lands” of the lower reaches of the Nile River. Because the IIP is financed through fees paid by the direct beneficiaries of the project, i.e., irrigation water users, these same Egyptian agricultural producers are especially sensitive to the higher than expected costs that the project has incurred to date. The objective of the current study is to evaluate whether this cost reduction is associated with any deficiency in irrigation performance. This Monitoring and Evaluation (M&;E) study aims to answer questions such as: Does reducing pump capacity and increased pump operation affect the farmers negatively? And, does the use of electricity instead of diesel fuel affect the farmers positively? Six indicators were used to compare new design criteria in the W10 and the IIP1 irrigation system designs, water savings, irrigation cost, irrigation time, night irrigation, and land savings. The W10 project design achieved the minimum actual operating cost per unit of area and per unit of water compared to the IIP1 project design on both Meet Yazied and El-Mesk Canals. The total cost per unit of area in the W10 project design is lower than IIP1 by 19.33% and 24.92% on the Meet Yazied and El-Mesk Canals, respectively. The total cost per unit of water in the W10 design is also lower than IIP1 on the Meet Yazied and El-Mesk Canals. Average irrigation time for rice and cotton crops cultivated in the W10 area are higher than average irrigation time for these crops cultivated in the IIP1 area for all locations on the Mesqa (head, middle and tail), because of increased pump operation in the W10 area (16 to 20 h d???1). The number of irrigation events at the head of the Sefsafa Canal in the W10 area is higher than on the Meet Yazied and El-Mesk Canals in the IIP1 areas because of the increased pump operation in the W10 area. 相似文献
112.
Water use patterns are not distributed evenly over space and time. Determining the amount of water used within a region, as
well as the various ways in which water is used is important for making adequate and sustainable water management policies
and determining future water availability. We examined differences in spatial trends in Oregon freshwater use (total, municipal,
and agricultural water withdrawals), by county, between the years 1985 and 2005. We also explored biophysical and socioeconomic
factors that explain spatial patterns using Moran’s I, local index of spatial autocorrelation (LISA), and spatial regression
models. There was a moderate positive spatial autocorrelation among counties that had similar total and irrigation withdrawals.
LISA analysis identified hot spots between certain arid agricultural counties in the southeastern Oregon and cold spots between
certain humid northwestern counties, including within the Portland metro area. Annual precipitation and income are negatively
associated with total water withdrawals. Summer temperature and farm size is positively associated with irrigation water withdrawals,
while net cash return and income are negatively associated with irrigation water withdrawals. When compared to ordinary least
square regression models, spatial error models that take into account spatial dependence provide a more comprehensive explanation
of the variations of water use, suggesting that water resource planning and management should incorporate spatial and neighborhood
effects to effective manage limited natural resources. 相似文献
113.
114.
根据可持续发展理论并借鉴现代企业核心能力理念,阐明了灌区持续发展能力的内涵,对灌区工程配套建设及现代化调控能力、市场化运转及协调能力、机制创新及规范化运作能力和以人为本的灌区服务能力进行了系统分析。结合皂河灌区实践探讨了灌区持续发展能力建设的途径,科学评价了灌区能力建设的效果。对促进大型灌区科学、高效管理体制和良性运行机制的建立,提高大型灌区的可持续发展水平,具有重要的示范和推广作用。 相似文献
115.
杨光华 《华北水利水电学院学报》2012,(1):24-26,39
近年来国内外学者对农田水利的研究集中在制度、组织合作等方面。综述了集体行动与农田水利,集体行动、制度对我国农田水利建设的影响,指出目前研究的不足:缺少对个案的深入细致调查研究。 相似文献
116.
按照生态农业工程理论和抗旱节水工程技术要求,对棉花转基因抗旱品种、不同密度、不同基肥N、P的施用量进行田间水分胁迫综合试验.经在关中灌区3年试验研究结果表明:密度以每公顷种植7.5万株比种植4.5、6万株分别增产671.854、83.30 kg,增产57.49%和41.36%.品种陕402(早熟)、陕576(中早熟)分别比中棉所41(中熟)增产16.62%和16.17%.施磷酸二铵比尿素增产,每公顷施1502、25 kg分别增产11.35%和10.53%.抗旱节水农业工程育种和农艺节水工程技术结合,不仅可降低生产成本44%~47%,还可提高产量和品质,增收1 050~5 000元/hm2,同时节约了水资源,保护了农业生态环境. 相似文献
117.
在潦河灌区西潦北干五支渠安装了远程测控智能平板闸门装置,开展渠道自动量水监测试验,分析验证远程测控智能闸门装置的实际应用效果。结果表明:该技术能实现灌区明渠输配水的远程智能化控制、下泄水流量数据实时监测、统计,测流误差综合精度小于5%,测流精度和可靠度较好,该系统适用于灌区小型明渠输水控制,为灌区量水设施改造工作提供了有效手段。 相似文献
118.
César González-Cebollada Bibiana Macarulla David Sallán 《Canadian Metallurgical Quarterly》2011,137(6):375-382
This paper presents a new method to design pressurized branched irrigation networks. This method is called recursive design and is based on application of the problem-solving technique known as backtracking to the problem of the optimum design of pressurized branched irrigation networks with a known delivery piezometric head (pipe-sizing). Recursive design is a heuristic optimizer, like genetic algorithms, and has been implemented in a fast, versatile computer application. After presenting and precisely defining the design problem, the writers review the theoretical foundations of some of the main existing design methods: maximum velocity, recommended velocity, Mougnie velocity, constant hydraulic slope, Lagrange multipliers, linear programming, Labye’s method, and genetic algorithms. Next, the writers explain what recursive design consists of and apply its methodology in detail to a simple network. In the results section, the solutions obtained by recursive design are compared with those obtained by the other design methods, giving satisfactory results. For example, in an analyzed standard network, genetic algorithms take more than 20?minutes to offer a solution, whereas recursive design offers a cheaper solution with less than 3?seconds of computation time. 相似文献
119.
以GIS技术支持下的江西省农田节水灌溉系统为研究对象,阐述了系统研究的主要内容、方法和技术框架,并对GIS技术在节水灌溉中应用的特点及优势进行了分析。 相似文献
120.
Performance-Based Optimization of Land and Water Resources within Irrigation Schemes. I: Method 总被引:1,自引:0,他引:1
Sunil D. Gorantiwar Ian K. Smout K. Vairavamoorthy 《Canadian Metallurgical Quarterly》2006,132(4):332-340
Optimum land and water allocation to different crops grown in different regions of an irrigation scheme is a complex process, especially when these irrigation schemes are characterized by different soils and environment and by a large network of canals. At the same time if the water supply in the irrigation schemes is limited, there is a need to allocate water both efficiently and equitably. This paper describes the approach to include both productivity (efficiency) and equity in the allocation process and to develop the allocation plans for optimum productivity and/or maximum equity for such irrigation schemes. The approach presented in this paper considers the different dimensions of equity such as water distribution over the season, water distribution during each irrigation, and benefits generated. It also includes distribution and conveyance losses while allocating water equitably to different allocation units. This paper explains the approach with the help of the area and water allocation model which uses the simulation–optimization technique for optimum allocation of land and water resources to different crops grown in different allocation units of the irrigation scheme. 相似文献