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71.
辛提卡提出语言博弈理论旨在建立一种能用于系统分析或摹拟人的认识活动的过程及其结果的理论。这一理论以可能世界理论为基础 ,它把形式逻辑的模型集合建构看做一种特殊的博弈活动 ,用“寻找且找到博弈”描述以现实为对象的语言活动 ,并刻画了两种博弈之间的联系。“寻找且找到博弈”不同于运算 ,它的结局不是预先可断定的 ;而这一博弈规则是制约着语句F的整个证实过程的规则。  相似文献   
72.
本文较为详细地分析我们在1998 年上半年进行的“广州 市中学生课外科技活动问卷调查”的数据, 指出广州市中学生课外科技 活动存在着师资力量不足、考核制度不完善等问题, 文章最后提出了解 决上述问题的意见和看法  相似文献   
73.
Health Risk Assessment of a Modern Municipal Waste Incinerator   总被引:2,自引:0,他引:2  
During the modernization of the municipal waste incinerator (MWI, maximum capacity of 180,000 tons per year) of Metropolitan Grenoble (405,000 inhabitants), in France, a risk assessment was conducted, based on four tracer pollutants: two volatile organic compounds (benzene and 1, 1, 1 trichloroethane) and two heavy metals (nickel and cadmium, measured in particles). A Gaussian plume dispersion model, applied to maximum emissions measured at the MWI stacks, was used to estimate the distribution of these pollutants in the atmosphere throughout the metropolitan area. A random sample telephone survey (570 subjects) gathered data on time-activity patterns, according to demographic characteristics of the population. Life-long exposure was assessed as a time-weighted average of ambient air concentrations. Inhalation alone was considered because, in the Grenoble urban setting, other routes of exposure are not likely. A Monte Carlo simulation was used to describe probability distributions of exposures and risks. The median of the life-long personal exposures distribution to MWI benzene was 3.2·10–5 g/m3 (20th and 80th percentiles = 1.5·10–5 and 6.5·10–5 g/m3), yielding a 2.6·10–10 carcinogenic risk (1.2·10–10–5.4·10–10). For nickel, the corresponding life-time exposure and cancer risk were 1.8·10–4 g/m3 (0.9.10–4 – 3.6·10–4 g/m3) and 8.6·10–8 (4.3·10–8–17.3·10–8); for cadmium they were respectively 8.3·10–6 g/m3 (4.0·10–6–17.6·10–6) and 1.5·10–8 (7.2·10–9–3.1·10–8). Inhalation exposure to cadmium emitted by the MWI represented less than 1% of the WHO Air Quality Guideline (5 ng/m3), while there was a margin of exposure of more than 109 between the NOAEL (150 ppm) and exposure estimates to trichloroethane. Neither dioxins nor mercury, a volatile metal, were measured. This could lessen the attributable life-long risks estimated. The minute (VOCs and cadmium) to moderate (nickel) exposure and risk estimates are in accord with other studies on modern MWIs meeting recent emission regulations, however.  相似文献   
74.
This article explains the general nature of the business style of Toyota management strategy, its specific performance, and its development in China. It is quite difficult to find specific revolutionary policies and unusual strategies for the success of the Toyota Motor Corporation.  相似文献   
75.
翻译过程从本质上说是一个从"思维的抽象"到"思维的具体"的过程,是译者运用各种形式的决策思维将"思维的抽象"和"思维的具体"活动落到实处的过程,是一个充满着悬念和挑战的创造过程.从事翻译教学的教师要想达到让学生不但"知其然",而且还能"知其所以然"的理想目的,就要学会从思维的高度和深度去指导学生学习翻译,学会翻译.  相似文献   
76.
原因自由行为是为给那些由于行为人故意或过失地使自己陷入无责任能力,然后在无责任能力状态下,实施犯罪行为提供处罚依据的一种理论。然而,这一理论从一引进来就引起了学者们的激烈争论。对于这一理论,如何认定其着手,学者们意见分歧,本文认为在解决着手的认定之前,首先应当明确原因自由行为的处罚对象。原因自由行为中原因行为的可罚性。能否可以通过立法的方式赋予原因行为具有实行行为性,这是解决原因自由行为着手认定的关键所在。  相似文献   
77.
This paper seeks an account of why young teens initiate consensual sexual activity. It does so by constructing statistical models aimed at distinguishing those who report having initiated sexual activity from those who have not in four samples of eighth graders from an Upstate New York county. Theoretical selection of the model variables is guided by insights from problem syndrome, control and differential association theories. From our findings we conclude the following: (1) Risk behaviors foreseen by the problem syndrome approach, including having used marijuana and having been drunk, are significant, powerful predictors of early-teen sexual activity. (2) The social setting of consensual sexual activity differs by sex at the eighth grade level. For example, having a boyfriend is a more consistent, powerful predictor variable for girls than is having a girlfriend for boys and there is evidence to support the hypothesis that boys initiate sexual activity in the context of status-seeking while girls are more likely to do so as a way of attaining approval. (3) Our findings do not give clear primacy to parents or peers as an influence on early-teen consensual sexual activity. Both control theory, usually associated with parental-influence variables, and differential association theory, usually associated with peer-influence variables, receive support. (4) The results of the research spanning a 2-year period of intensive community antiteen-pregnancy efforts by a Zero Adolescent Pregnancy (ZAP) campaign are consistent with the conclusion that such a multifaceted approach might help lower early-teen initiation of sexual activity.  相似文献   
78.
不确定环境中,项目进度计划鲁棒性的高低直接影响项目能否顺利实施。本文研究了具有随机活动工期的柔性资源约束下的前摄性项目调度优化问题,目标是在柔性资源和项目工期的约束下,借助对活动开始时间合理的进行安排进而得到拥有最大鲁棒性的进度计划。首先对研究问题进行界定;随后构建优化模型,并根据问题NP-hard属性和模型特点设计了双层嵌套禁忌搜索启发式算法,通过内外两层交互搜索寻找满意解;最后通过一个实际案例对本文研究进行说明,并分析关键参数对进度计划鲁棒性的影响,得到如下结论:相对于资源无柔性情况下的项目进度计划而言,资源具备柔性后得到的项目进度计划的鲁棒性更高,具有更强的抗干扰能力,能够保证项目稳定执行;同时,项目进度计划鲁棒性分别随着项目工期的延长、资源可用量的增加或资源柔性的提高而上升。  相似文献   
79.
Objective: Researchers have yet to explore the effect of physically interactive video game playing on energy expenditure, despite its potential for meeting current minimal daily activity and energy expenditure recommendations. Participants and Methods: Nineteen male college students-12 experienced Dance Dance Revolution (DDR) players and 7 inexperienced players- completed maximal oxygen uptake assessments and a 30-minute DDR gaming session. The authors recorded heart rate (HR), rating of perceived exertion (RPE), respiratory exchange rate (RER), oxygen consumption (VO2), and total steps (TS30). Results: Experienced participants showed higher exercise HR, RPE, RER, VO2, total and relative energy expenditure, exercise intensity, TS30, and average steps per minute, and less time and steps to expend 150 kilocalories (p < .05). Conclusions: Participants with greater playing experience can work at higher intensities, promoting greater energy expenditure.  相似文献   
80.
1994年联合国人口与发展大会后 ,全球用于人口活动的国际援助和国内资金投入逐年增加 ,其总数达到约 110亿美元。国际援助主要包括捐助国双边援助、联合国系统的多边援助及非政府组织私人捐助等。 1999年国际援助达到 2 2亿美元 ,各国国内用于人口活动的资金开支估计达到89亿美元。国际援助资金与联合国人发大会《行动纲领》确定的 2 0 0 0年国际援助应为 5 7亿美元的目标相比 ,仍有较大距离 ,仅达到这一目标的 38%多一点。资金缺乏仍然是限制全面执行《行动纲领》的主要问题之一。  相似文献   
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