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Given a simple polyhedron P in the three dimensional Euclidean space, different tetrahedralizations of P may contain different numbers of tetrahedra. The minimal tetrahedralization is a tetrahedralization with the minimum number of tetrahedra. In this paper, we present some properties of the graph of polyhedra. Then we identify a class of polyhedra and show that this kind of polyhedra can be minimally tetrahedralized in O(n
2) time. 相似文献
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Anže Burger Björn Jindra Philipp Marek Matija Rojec 《Journal of International Management》2018,24(2):108-122
This paper investigates the relationship between the value capture of multinational subsidiaries and functional upgrading, which is defined as a diversification of employment from primary business functions to higher value adding activities such as ICT, R&D, marketing or logistics. By combining survey-based business function indicators with longitudinal accounting data for a representative sample of multinational subsidiaries located in six Central and Eastern European countries (CEECs), we assess the impact of functional upgrading on foreign subsidiaries' value capture. The results provide robust evidence that the breadth as well as the scope of functional upgrading induces an upward shift of subsidiaries' value added. The effect of functional upgrading is stronger in the earlier phases after entry of the foreign investor, while the long-term growth trend remains unaffected. 相似文献
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目前扣除系数的计算方法主要为分析法与模拟法,扣除系数的常见影响因素有客货列车速度比、区段均衡度、追踪间隔时分等。通过模拟法进行不同客货列车速度比下的运行图铺画,得出客货列车速度比对扣除系数的影响规律分析。实验表明:随着客货速度比的增加,扣除系数将逐渐变大,据此建议在相关双线客货混跑区段,选取合适的客货速度比,以减小对运行图通过能力的影响 相似文献
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Juvenile crime affects not only the victims of the crime but also the delinquents’ future. How to prevent adolescent criminal behavior has become an important public policy issue. This study contributes to this interesting issue by examining the relationship between tattooing and adolescents’ criminal behavior. In particular, this study investigates whether or not having a tattoo/tattoos is connected to the incidence of various criminal activities, including: larceny, robbery, fraud, assault, drug use, and homicide. A unique sample of 973 juvenile detainees drawn from the administrative profiles in Taiwan and the coarsened exact matching method were utilized. Results show that compared to their nontattooed counterparts, tattooed juvenile detainees were significantly more likely to commit fraud, assault, drug abuse, and homicide by 3%, 13%, 9%, and 9%, respectively. In contrast, tattooing was not significantly associated with larceny or robbery. From a policy perspective, given the significant link between tattooing and criminal behavior, the presence of a tattoo in adolescents may serve as a valuable indicator regarding adolescents’ high probability of committing crimes. 相似文献
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We examined the moderating roles of individualistic and collectivistic cultural orientations and academic achievement on the relation between Chinese adolescents’ shyness and depressive symptoms. A sample of Chinese adolescents (N = 492) from an urban school participated in the study during seventh (T1) and eighth (T2) grades. Adolescents self‐reported their shyness, cultural orientations, and depressive symptoms. The school provided records of their academic achievement. Concurrently, shyness and individualism were positively whereas collectivism and academic achievement were negatively, associated with adolescents’ depressive symptoms. Longitudinally, T1 shyness (but not individualism, collectivism, or academic achievement) predicted T2 depressive symptoms after controlling for stability in depressive symptoms. Concurrent relations between shyness and depressive symptoms were moderated by adolescents’ cultural orientations. Specifically, collectivism was protective whereas individualism was harmful, for shy adolescents’ adjustment. Furthermore, collectivism and academic achievement jointly moderated the relations between shyness and depressive symptoms concurrently and longitudinally. The results suggest that cultural orientations may influence shy adolescents’ depression symptoms through individual‐level self‐evaluation, and indicate that cultural factors and academic achievement need to be considered comprehensively for understanding and improving shy Chinese adolescents’ psychological adjustment. 相似文献
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Development of predictive signatures for treatment selection in precision medicine with survival outcomes
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For survival endpoints in subgroup selection, a score conversion model is often used to convert the set of biomarkers for each patient into a univariate score and using the median of the univariate scores to divide the patients into biomarker‐positive and biomarker‐negative subgroups. However, this may lead to bias in patient subgroup identification regarding the 2 issues: (1) treatment is equally effective for all patients and/or there is no subgroup difference; (2) the median value of the univariate scores as a cutoff may be inappropriate if the sizes of the 2 subgroups are differ substantially. We utilize a univariate composite score method to convert the set of patient's candidate biomarkers to a univariate response score. We propose applying the likelihood ratio test (LRT) to assess homogeneity of the sampled patients to address the first issue. In the context of identification of the subgroup of responders in adaptive design to demonstrate improvement of treatment efficacy (adaptive power), we suggest that subgroup selection is carried out if the LRT is significant. For the second issue, we utilize a likelihood‐based change‐point algorithm to find an optimal cutoff. Our simulation study shows that type I error generally is controlled, while the overall adaptive power to detect treatment effects sacrifices approximately 4.5% for the simulation designs considered by performing the LRT; furthermore, the change‐point algorithm outperforms the median cutoff considerably when the subgroup sizes differ substantially. 相似文献
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纳博科夫是一位视觉艺术大师,这是理解其小说创作的关键.纳博科夫反复声明自己天生是画家,具有特殊的听音辨色的“色彩听觉”天赋,其作品运用文字呈现出五光十色的艳丽色彩.纳博科夫对古往今来欧美列国的画家画作了然于心,其创作过程即如作画般在纸张的画布上挥毫泼墨,实践着“诗如画”的书写传统.除了斑斓的五彩世界与绘画般的文字书写,纳博科夫的小说还大量借鉴了电影叙事技巧.在文字与视觉艺术之间,纳博科夫自觉且自如地进行着空间书写. 相似文献
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提高农村居民信息意识是农业现代化和农业信息化的具体要求,也是实现农业现代化和农业信息化的重要途径。本文通过对西北四省(陕西、甘肃、宁夏、青海)1 561位农村居民的调研,从农村居民对信息的信任度、关注度、认可度三个维度分析了该区域农民的信息意识现状。研究重点对比了农民信息意识在不同个体特征要素(性别、年龄、文化程度、务农经验)和信息传播系统要素(邻里系统、大众媒介系统)之间表现出的差异性,并在此基础上提出了提升农村居民信息意识的相关建议。 相似文献