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101.
在英语并列疑问句中,存在着ATB(Across the Board)移位现象。汉语作为Wh in situ的语言,不允许疑问词提升。但是通过对实际的语料分析发现,在汉语某些宾语前置的话题结构中,同样存在着ATB式移位。文章通过分析这些结构的句法特征和生成机制,证明了在汉语中同样存在着ATB移位现象,并通过对比不同语言中话题化结构的特点,进而证明了ATB移位具有跨语言的普遍特性。  相似文献   
102.
Several colorectal cancer (CRC) screening models have been developed describing the progression of adenomas to CRC. Currently, there is increasing evidence that serrated lesions can also develop into CRC. It is not clear whether screening tests have the same test characteristics for serrated lesions as for adenomas, but lower sensitivities have been suggested. Models that ignore this type of colorectal lesions may provide overly optimistic predictions of the screen‐induced reduction in CRC incidence. To address this issue, we have developed the Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) model that includes the adenoma‐carcinoma pathway and the serrated pathway to CRC as well as characteristics of colorectal lesions. The model structure and the calibration procedure are described in detail. Calibration resulted in 19 parameter sets for the adenoma‐carcinoma pathway and 13 for the serrated pathway that match the age‐ and sex‐specific adenoma and serrated lesion prevalence in the COlonoscopy versus COlonography Screening (COCOS) trial, Dutch CRC incidence and mortality rates, and a number of other intermediate outcomes concerning characteristics of colorectal lesions. As an example, we simulated outcomes for a biennial fecal immunochemical test screening program and a hypothetical one‐time colonoscopy screening program. Inclusion of the serrated pathway influenced the predicted effectiveness of screening when serrated lesions are associated with lower screening test sensitivity or when they are not removed. To our knowledge, this is the first model that explicitly includes the serrated pathway and characteristics of colorectal lesions. It is suitable for the evaluation of the (cost)effectiveness of potential screening strategies for CRC.  相似文献   
103.
研究了碎纸片的拼接复原问题,建立了合理有效的碎纸片拼接复原的数学模型;给出了数学软件实现自动拼接的具体算法;结合人工拼接得出复原图片;最后,对所给的拼接方法提出了改进方向.  相似文献   
104.
Outcome editing refers to a set of mental rules that people apply when deciding whether to evaluate multiple outcomes jointly or separately, which subsequently affects choice. In a large-scale online survey (n = 2062) we investigate whether individuals use the same outcome editing rules for financial outcomes (e.g., a lottery win) and social outcomes (e.g., a party with friends). We also test the role of numeric ability in explaining outcome editing. Our results show that people’s preferences for combining or separating events depend on whether those events are in the financial or the social domain. Specifically, individuals were more likely to segregate social outcomes than monetary outcomes, except for when all outcomes were negative. Moreover, numeric ability was associated with preferences for outcome editing in the financial domain but not in the social domain. Our findings extend the understanding of the arithmetic operations underlying outcome editing and suggest that people rely more on calculations when making choices involving multiple financial outcomes and more on feelings when making choices involving social outcomes.  相似文献   
105.
A charitable donor typically imitates the majority contribution of other donors. This study examines the relationships between majority size and this so-called donor’s conformity behavior, by empirically investigating the impacts of multiple earlier donations on the donation of a subsequent donor to JapanGiving, a donation-based crowdfunding platform in Japan. This analysis is possible because the platform’s webpage displays the previous donation amounts in chronological order, thus allowing us to examine the modal amount of more recent donations. By using data on 9989 actual donations, our dynamic panel analysis suggests that when the number of most recent continuous modal donations increases, the likelihood that a subsequent donor matches the modal amount increases. This result supports the notion that a donor’s conformity behavior is more likely to occur when a greater proportion of other donors give a similar amount. Furthermore, the effects of continuous modal donations are strongly observed for low monetary ranges. We interpret that initiating further cooperation among a large number of less cooperative other donors would become harder, or individuals would obtain an excuse for less cooperation due to the others’ behaviors. Finally, we discuss how our findings connect economic studies of charity and social psychology studies of conformity and could help improve the effectiveness of fundraising by charities.  相似文献   
106.
India made patent policy changes to comply with TRIPs agreement that increased the rights of patent owners. Considering that such policy changes influence both in-house research and development investments and technology licensing from external sources, the firms have to accordingly devise their technology strategy. This study employs a simple and fixed effects multinomial logit regression models to study the impact of policy changes on the technology strategy of 402 firms operating in Indian manufacturing sector from 1999 to 2014. The results show that changes in patent policy have a significant impact on technology strategy of firms.  相似文献   
107.
Post-crisis policy making increasingly focuses on doing business reforms. We argue that the effects of those reforms will be different across countries. To understand the reasons for the reform outcome divergence, we advance a novel firm-size distribution (FSDs) argument. At the center of the argument is the fact that FSDs are different across countries and stable over time. Then, if a given doing business reform induces firms of different size to grow differently, this will produce a variety of reform outcomes across countries. To advance the argument, we set up a tractable general equilibrium (GE) model and study how firms of different size grow after a doing business reform. The model predicts that larger firms will grow faster than smaller firms after the reform. The model predictions are tested on the Enterprise Surveys (ES) data, merged with the Doing Business indicators. We confirm that firms of different size grow differently after a Doing Business reform. Thus, based on the notable differences of firm size distributions across countries, identical reforms to start, operate and close a business will produce a variety of reform outcomes across countries.  相似文献   
108.
提出一种适用于DSP的基于Bessel插值结构的正交数字下变频方案,可实现已调信号调制方式的自动识别。该方案能够实现提取信号的正交分量和同相分量,并且能够提取出较高精度的信号的基本参数,由此得到的特征参数可以准确地识别出信号的调制模式。最后,通过计算机和DSP仿真,证明了它的可行性。  相似文献   
109.
An analytic methodology for patient enrollment modeling using a Poisson-gamma model is developed by Anisimov & Fedorov (2005–2007). For modeling hierarchic processes associated with enrollment, a new methodology using evolving stochastic processes is proposed. This provides rather general and unified framework to describe various operational processes associated with enrollment. The technique for calculating predictive distributions, mean, and credibility bounds for evolving processes is developed. Some applications to modeling operational characteristics in clinical trials are considered with focus to modeling events associated with incoming and follow-up patients in different settings. For these models, predictive characteristics are derived in a closed form.  相似文献   
110.
摘 要:应用儿童长处与困难(SDQ)问卷(父母版),采用分层随机抽样方法,对惠州市1528名3-6岁儿童的情绪与行为问题进行调查。研究发现:惠州市3-6岁儿童情绪与行为问题异常情况比较严峻,儿童心理健康状况值得重视;不同地域、年龄学前儿童存在不同的情绪与行为问题,需要分类干预。其中农村儿童的情绪与行为问题异常情况尤为严重,需要得到广泛的关注和解决。  相似文献   
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