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71.
C语言程序题的判阅是计算机考试中的重要部分。以往计算机判阅C语言程序题时,由于学生编写的C语言程序题死循环程序比较多,导致了计算机死机问题产生。因此提出了C程序移置到VC 程序环境中再编译执行的方法,当出现死循环情况对其执行的对话框进行关闭,解决了计算机死机的问题。  相似文献   
72.
直升机环量控制尾梁截面形状分析   总被引:2,自引:0,他引:2  
基于二维可实现k-Epsilon湍流模型模拟计算了直升机环量控制尾梁上的升力,并与试验结果进行了对比,计算结果与试验结果之间显示出了可接受的吻合度。利用已验证的数值计算方法和网格划分方法,分别计算了三组不同截面形状的环量控制尾梁在不同几何参数(喷射角、缝位角、基准直径和狭缝数量)或试验条件(喷射气流速度、下洗流速度)下的升力。结果显示,通过优化尾梁截面形状和狭缝相对位置,引导气流在截面曲率较大的位置处脱离壁面,可以提高尾梁升力并增强附壁气流的稳定性。模拟计算结果还揭示了提高下洗流速度和降低狭缝喷射角可以提高优化尾梁截面和狭缝相对位置的效果。  相似文献   
73.
Human habitation and animal holding experiments in a closed environment, the Closed Ecology Experiment Facilities (CEEF), were carried out. The CEEF were established for collecting experimental data to estimate carbon transfer in the ecosystem around Rokkasho nuclear fuel reprocessing plant. Circulation of O2 and CO2, and supply of food from crops cultivated in the CEEF were conducted for the first time in the habitation experiments. Two humans known as eco-nauts inhabited the CEEF, living and working in the Plant Module (PM) and the Animal and Habitation Module (AHM), for a week three times in 2005. On a fresh weight basis, 82% of their food was supplied from 23 crops including rice and soybean, cultivated and harvested in the PM, in the 2nd and 3rd experiments. For the goats, the animals held in the experiments, all of their feed, consisting of rice straw, soybean plant leaves, and peanut shells and peanut plant leaves, was produced in the PM in the 2nd and 3rd experiments. The O2 produced in the PM by photosynthesis of the crops was separated by the O2 separator using molecular sheaves, then accumulated, transferred, and supplied to the AHM atmosphere. The CO2 produced in the AHM by respiration of the humans and animals was separated by the CO2 separator using solid amine, then accumulated, transferred, and supplied to the PM atmosphere. The amount of O2 consumed in the AHM was 46–51% of that produced in the PM, and the amount of CO2 produced in the AHM was 43–56% of that consumed in the PM. The surplus of O2 and the shortage of CO2 was a result of the fact that waste of the goats and the crops and part of the human waste were not processed in these habitation experiments. The estimated amount of carbon ingested by the eco-nauts was 64–92% of that in the harvested edible part of the crops. The estimated amount of carbon ingested by the goats was 36–53% of that in the harvested inedible part of the crops. One week was not enough time for determination of gas exchange especially for humans and animals, because fluctuation of their gas exchange was quite high. The amount of transpired water collected as condensate was 818–938 L d−1, and it was recycled as replenishing water compensating transpiration loss of nutrient solution. The amount of waste nutrient solution discharged from the PM was 1421–1644 L d−1. The waste nutrient solutions from rice and other crops were processed through micro filters (MFs) separately. The MF filtrated solutions were processed with reverse osmosis (RO) membrane filter separately and divided into filtrated water and concentrated waste nutrient solution. The concentrated waste nutrient solution from the crops other than rice was processed through an ultra-micro filter (UF) and reused, although that from rice was discharged in 2005. Concentrations of nutritional ions in the UF filtrated solution were determined, the depleted ions were added back, the UF filtrated solution was diluted with the RO membrane filtrated water, and the nutrient solution for the crops other than rice was regenerated. The nutrient solution for rice was newly made each time, using concentrated solution from an external source and the RO membrane filtrated water. Average amounts of water used in the AHM (L d−1) were determined as follows: drinking by humans (filtrated water), 1.5; cooking, etc. (filtrated water other than for drinking), 14.3; drinking by goats, 3.8; showering (hot water), 13.2; showering (cold water), 0.1; washing of hand and face and brushing teeth, 4.1; washing of dishes, dish clothes and towels, 36.4; and washing of animal holding tools, 0.3. The waste water was processed by a RO purification system and recycled for toilet flushing and animal pens washing. A circulation experiment for water was started in 2006 and a circulation experiment for waste materials is planned for 2007. In 2006, a single duration of the air circulation experiments was 2 weeks, although the human habitants were changed after 1 week.  相似文献   
74.
通货紧缩是指一般物价指数的持续下降,它是一种货币现象,表现为货币供不应求。当前人民币供给的增长速度大于GDP的增长速度,人民币供不应求的原因在于其流通速度下降幅度超过了供给增长速度。人民币流通速度下降是因为社会公众以货币形态持有收入倾向的增强。所以,货币需求过快上升引发了通货紧缩。  相似文献   
75.
AVHRR MCSST data for the periods 1982–2000 (mean weekly data) were used to calculate mean gradient fields in the ocean for different periods of time. Three-month averaged sea surface temperature gradients (SSTG) and their mean seasonal variations have been studied for 25 points in the large-scale oceanic fronts zones. Major oceanic fronts in the Atlantic and Pacific have been identified and compared in literature. In the North Atlantic and Pacific, the areas under study were the North Polar Front and Subpolar Fronts. In the South Atlantic and Pacific we studied the region of the Antarctic Circumpolar Current (ACC) and the fronts formed by this current, known as the South Polar Front, and the Subantarctic Front. SSTG were also calculated for El Niño (Southeast Pacific) and Benguela Current (Southeast Atlantic).  相似文献   
76.
纵向尾流间隔计算方法研究   总被引:1,自引:0,他引:1  
综合考虑了飞机的速度、翼展、机翼面积、发动机推力等参数,应用空气动力学中的环量计算理论、尾流消散原理等,将动量定理和涡阻力的计算原理应用到尾流间隔的计算,分别建立了纵向尾流间隔计算模型。采用实际数据计算验证模型的正确性。  相似文献   
77.
We have shown in several recent publications that it is necessary to group the meteorological data according to the phase of the Quasi-Biennial Oscillation (QBO) throughout the year, in order to find a clear signal of the 11-year sunspot cycle (SSC). This work is summarized here. It is the purpose of this paper (1) to update earlier results of the solar cycle – QBO relationship for the northern winter, (2) to stress the interaction between the hemispheres and (3) to summarize the influence of the QBO on the solar variability signal, as well as the influence of the solar variability signal on the QBO throughout the year. For this, the constructed annual mean of the solar cycle – QBO relationship is introduced.  相似文献   
78.
为了进一步探索环槽铆钉在航天产品上使用的可靠性,经过15年的自然环境露天贮存,研究其抗腐蚀性能和机械性能,为航天产品更广泛的使用环槽铆钉提供可靠的依据。对已用在航天产品上的环槽铆钉,经过陆地环境条件下露天贮存5年,又继续在海洋环境条件下露天贮存4年.接着又在陆地环境条件下露天贮存6年.前后共贮存15年,进行了全面系统分析,从而得出环槽铆钉在航天产品上使用是完全可靠的结论。  相似文献   
79.
因失重时血循环系统的改变十分类似于中医“血淤症”时的变化,故采用活血化淤中药来改善失重时的血循环状态可能是一种较好的防护措施。实验比较了4种中药(丹-黄合剂、川芎、冠心Ⅱ号、樟柳碱)对模拟失重兔耳微循环和血液流变性的影响。结果表明4种中药均有改善模拟失重兔血循环的作用,其效果是丹-黄合剂>川芎>冠心Ⅱ号>樟柳碱。两种药量实验结果表明丹黄合剂用15g/kg,川芎用10g/kg 效果较好。  相似文献   
80.
刑事审判中因证人不愿出庭作证,使修订后《刑事诉讼法》关于“证人应当出庭作证”的规定不能得到执行,因而,当前急需在立法上完善证人作证制度。  相似文献   
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