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排序方式: 共有327条查询结果,搜索用时 15 毫秒
1.
设计了控制电梯运行的调度算法;其次,采用面向对象语言编写程序模拟电梯运行,其中使用双缓冲技术来解决电梯图片在刷新过程中出现的闪烁现象;最后,测试该系统的正确性和合理性。  相似文献   
2.
In order to help tourists choose satisfying scenic spots, content hotels, convenient lines and convenient vehicles, vehicle monitoring control and scheduling management system in a scenic area is presented, which dispatches vehicle by appointments and the statistic of tourists at a sight spot and recommends the tour line by broadcasting in vehicle. Vehicle monitoring control and scheduling management system in a scenic area, a integrative vehicle management system, is an integration of GPS, GIS, trunked radio system, a management system of booking room and a tourist statistic system at a sight spot.  相似文献   
3.
The traditional scheduling for vehicle is option in the fixed network. But it can't satisfy the real time environment. The demand of order is changeable and uncertain in real environment. It is convenient for scheduling transforming it into static data, but can't get the advantage on time. This paper proposes a real time vehicle scheduling on the study of traditional scheduling and discusses the model structure and the key technology for the real time system that establishes the base for develop teal time system.  相似文献   
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Recent droughts in the humid southeastern United States have focused attention on the need for and use of supplemental irrigation. Total annual rainfall amounts are sufficient for most crops in the region. However, erratic distribution of rainfall and the low water-holding capacities of most soils in the region cause frequent drought stresses in many crops. An on-farm study was conducted in southeastern Alabama to evaluate the effects of farmers' irrigation scheduling decisions on soil moisture variations in peanut fields irrigated with center-pivot irrigation systems. The study showed that the way irrigation was practiced in this high rainfall area often caused soil moisture deficit (SMD) level higher than the desired SMD limit during over 20% of the 140-day growing season. This is partially due to farmers' tendency to delay irrigation in anticipation of rainfall which may or may not occur, as rainfall during the growing season is often erratic and local. In contrast SMD in non-irrigated fields was higher than the SMD limit for half of the growing season.Abbreviations SMD soil moisture deficit - ET evapotranspiration - Reff effective rainfall - WHC water holding capacity  相似文献   
6.
The use of commercially available spreadsheet programs for scheduling of water supplies for large scale irrigation networks is a relatively new phenomenom. The paper describes the development and application of such a program for a 30 000 ha irrigation scheme in the Brantas Delta, East Java. The program has been in use for day-to-day scheduling of main system supplies since April 1986, during which time refinements and adjustments have been necessary to formulate a working package. The paper draws conclusions regarding the value of the program for improving water management.  相似文献   
7.
本文介绍了中日双方专家团在海子水库灌区现场调查中,实测土壤水分特征值的方法,土壤水分曲线的制定和应用,负压计观测值的应用,计算节水型灌溉用水量和灌水间隔日数的方法,并用节水型频繁灌溉法制定了各作物的节水型灌溉制度,用这种方法制定的节水型灌溉制度要比我国过去用的常规法节水40%以上。  相似文献   
8.
Crop-water production functions (CWPFs) are a useful tool for irrigation planning, but derivation of CWPFs by field experimentation is expensive, and traditional analytical techniques are not well suited to derivation of CWPFs. Physiologically based crop models provide a useful tool for simulation of agricultural experiments, but they have not been extensively applied to the task of CWPF determination. A new algorithm type based upon differential crop yield response to irrigation (“yield–irrigation gradients” [YIG]) is presented that uses these crop models to determine planning-level irrigation schedules and CWPFs. Three specific algorithms are developed within this type, varying in complexity, performance, and computational costs. Performance of the YIG methods is compared against a standard reference evapotranspiration method. In particular, the randomized iterative YIG (RIYIG) algorithm provides near-optimal results but at the highest computational costs of all the methods specified. All of the techniques presented have general applicability and are not limited to any one crop or location.  相似文献   
9.
为了快速、准确的分析水情实况、预测未来的发展趋势,结合清江流域防洪减灾工作实际情况,设计了实时水情调度联合计算方案。根据清江流域地理位置的特点,将其分为7个子流域,依次进行降雨径流预报、洪水演算,为防洪减灾提供真实有效的决策依据。通过对该方案的分析,探讨了设计思路,并给出了其实现机理。该方案已在“数字清江”项目中得到成功应用。  相似文献   
10.
冬小麦节水高效优化灌溉制度模型应用研究   总被引:4,自引:1,他引:4  
根据霍泉灌区田间试验资料,考虑水分亏缺的后效性,以冠层叶面积指数修正后的作物-水模型作为目标函数,建立二雏动态规划模型,计算冬小麦节水高效优化灌溉制度。结果显示,该模型充分反映了灌水时间、灌水定额和灌溉水量产生的冬小麦的产量效应,所建模型和参数确定较合理,在实践中更有实用性。  相似文献   
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