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31.
介绍了使用PC1D 5.9软件模拟高效单晶硅太阳能电池的方法。通过建立太阳能电池的结构模型和参数模型,在模拟的电池测试环境下,仿真得到太阳能电池的电压-电流曲线和量子效率曲线,并根据太阳能电池的理论,计算填充因子和转换效率的值。 相似文献
32.
Arthur E. Hamalainen 《Social Studies》2013,104(6):250-252
Online role-playing games such as World Of Warcraft represent new participatory cultures in which today's students engage every day. They are appealing to players largely because of the social aspects of game play. Some features of massively multiplayer online role-playing games (MMORPGs) can be incorporated into classroom culture to create more dynamic interactions between students and improve both content instruction and civic competence. 相似文献
33.
Henry Krips 《Cultural Studies》2013,27(1):78-114
Abstract The orthodox interpretation of Quantum Mechanics was banned in the Soviet Union in 1947, an episode usually glossed as another illustration of repressive Soviet science. This paper argues that the roots of this ban should be located at a much deeper level, in a tension existing between the ‘postmodern’ form of orthodox Quantum Mechanics and an ideology of modernization. In the West a similar ideological tension had a different result: when the occasion demanded, the orthodox interpretation was covertly exchanged for an agnosticism about metaphysical matters, and potential areas of conflict with the principles of modernization were thus defused. The latter strategy benefited the orthodox interpretation, which enjoyed a virtual monopoly in the West from the 1940s through to the 1960s. Using the Freudian notions of ‘transference’ and ‘disavowal’, I explain why the ideological tension with modernization was resolved differently in the West and in the Soviet Union. 相似文献
34.
Large initial investment in advanced manufacturing systems (AMS) makes it imperative to develop economic justification methods. Once the new system has been properly justified, a critical issue facing the firm is the optimal timing of the installation in an industry. In this paper we use a game-theoretic model by which the optimal timing of the investments in AMSs is analysed. The existence of timing equilibria is demonstrated and simple decision rules of optimal strategy are provided. Economic interpretations of the decision rules are subsequently made clear. Finally, illustrative examples are used to demonstrate the correctness and usefulness of the analysis. 相似文献
35.
36.
双寡头市场的调控机制研究 总被引:3,自引:2,他引:1
基于对策论和优化理论,本文研究了双寡头市场的调控机制。提出了政府依据市场上产品价格信号进行市场干预的必要性和调节方法。 相似文献
37.
《Journal of American college health : J of ACH》2013,61(5):505-512
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
38.
Dacheng Chen Juin Kuan Chong 《Journal of Statistical Computation and Simulation》2017,87(9):1863-1876
We propose a competing risks approach to analyse customer behaviours in freemium products and services. The event of interest is when a customer starts to pay for additional features or functionalities. The observation of such an event may be preempted by an event where the customer quits using the product before paying and consuming the additional features or functionalities. One such freemium service is the online game category. The Fine-Gray regression model was implemented for an online game player activity data to study how covariates affect the paying hazard. Some covariates are hypothesized to have different discrete effects at multiple change points. We extend the model to allow for possible change points in the analysis. 相似文献
39.
Jennifer M. Cameron MS Natalie Heidelberg MS Lisa Simmons BS Sarah B. Lyle BS Kathakali Mitra-Varma PhD Chris Correia PhD 《Journal of American college health : J of ACH》2013,61(5):499-506
Abstract Objectives, Participants, Methods: Drinking game participation has increased in popularity among college students and is associated with increased alcohol consumption and alcohol-related problems. The current study investigated drinking game participation among 133 undergraduates attending National Alcohol Screening Day (NASD) in April of 2007. Results: A large percentage of the sample reported lifetime (77%) and recent (52%) drinking game participation. Males were more likely to report recent participation and reported higher levels of consumption while playing drinking games. Drinking game participants were more likely to experience a range of alcohol-related problems, and the relationship between drinking game participation and alcohol-related problems was mediated by weekly alcohol consumption. Conclusions: These results suggest that drinking game participation is a risk factor for elevated levels of alcohol consumption and alcohol-related problems. Programs should be developed to educate students about the risks of drinking game participation, and prevention programs like NASD should address drinking games. 相似文献
40.
VICTOR AGADJANIAN 《Population studies》2013,67(2):135-148
This study examines how the social environment of religious congregations affects the spread of contraceptive use in developing contexts, using Mozambique as a case study. Analysis of qualitative data collected in urban areas of that country in 1998-99 and of the data from the 1997 Mozambique Demographic and Health Survey suggests that, in urban areas, the environment of more socioculturally diverse and inclusive Roman Catholic and mission-based Protestant congregations is more propitious to the spread and legitimization of modern contraception than the milieu of smaller, relatively homogeneous, independent churches. In rural areas, however, sociocultural diversity within and across different religious denominations is minimal, and membership in any formal congregation offers an advantage in contraceptive learning. 相似文献