The Limits of Black Politics in the Post–Civil Rights Era

Pluralist theorists have long contended that to exercise power and influence in the American political system, blacks should come together like any other organized interest group, form coalitions with other like-minded people (white liberals), and advocate for policy reforms. Beginning during the “Black Power” era, the goal of putting black faces in high places to help address black concerns became a driving force in black politics. The deteriorating social and economic status of many in the black community, however, has not been prevented by either the political incorporation of more than 11,000 black elected officials or even the election of the nation’s first black president. This article will show how the inherent limitations of the pluralist interest-group strategy and a growing white backlash fueled by an awareness of changing demographics in the country has spawned an economic and political crisis in black America.     

制造系统生产单元碳排放核算模型

制造业是我国国民经济的支柱产业，但也是环境污染物排放的主要来源、能源消耗主体和温室气体排放大户。制造系统高能耗、高物耗、高碳排放的加工过程是造成制造业碳排放量大的重要原因。生产单元作为制造系统的加工的主体，其碳排放量的核算是确定整个制造系统乃至制造业碳排放总量的关键。本文首先对生产单元的原材料、电能、辅助物料及废屑处理所引起的碳排放进行分析，确定生产单元的碳排放源；其次，产品合格率的不同会造成生产单元输入及输出的成品/半成品数量的差异，进而影响生产单元单位产品的碳排放量，在此基础上，综合考虑了原材料、电能、辅助物料及废屑处理的碳排放情况，构建了给定工艺流程下生产单元碳排放核算模型。最后，结合一汽车排气装置加工实例，分别核算加工过程中九个生产单元的碳排放量，验证了模型的可行性。     

Toward an Application Guide for Safety Integrity Level Allocation in Railway Systems

The work in the article presents the development of an application guide based on feedback and comments stemming from various railway actors on their practices of SIL allocation to railway safety‐related functions. The initial generic methodology for SIL allocation has been updated to be applied to railway rolling stock safety‐related functions in order to solve the SIL concept application issues. Various actors dealing with railway SIL allocation problems are the intended target of the methodology; its principles will be summarized in this article with a focus on modifications and precisions made in order to establish a practical guide for railway safety authorities. The methodology is based on the flowchart formalism used in CSM (common safety method) European regulation. It starts with the use of quantitative safety requirements, particularly tolerable hazard rates (THR). THR apportioning rules are applied. On the one hand, the rules are related to classical logical combinations of safety‐related functions preventing hazard occurrence. On the other hand, to take into account technical conditions (last safety weak link, functional dependencies, technological complexity, etc.), specific rules implicitly used in existing practices are defined for readjusting some THR values. SIL allocation process based on apportioned and validated THR values is finally illustrated through the example of “emergency brake” subsystems. Some specific SIL allocation rules are also defined and illustrated.     

The echo chamber is overstated: the moderating effect of political interest and diverse media

ABSTRACT

In a high-choice media environment, there are fears that individuals will select media and content that reinforce their existing beliefs and lead to segregation based on interest and/or partisanship. This could lead to partisan echo chambers among those who are politically interested and could contribute to a growing gap in knowledge between those who are politically interested and those who are not. However, the high-choice environment also allows individuals, including those who are politically interested, to consume a wide variety of media, which could lead them to more diverse content and perspectives. This study examines the relationship between political interest as well as media diversity and being caught in an echo chamber (measured by five different variables). Using a nationally representative survey of adult internet users in the United Kingdom (N?=?2000), we find that those who are interested in politics and those with diverse media diets tend to avoid echo chambers. This work challenges the impact of echo chambers and tempers fears of partisan segregation since only a small segment of the population are likely to find themselves in an echo chamber. We argue that single media studies and studies which use narrow definitions and measurements of being in an echo chamber are flawed because they do not test the theory in the realistic context of a multiple media environment.     

提升中小学生阅读兴趣的实证研究——基于MIMIC模型的教学效能分析

提升学生的阅读素养是当前我国阅读课程教学改革的重要目标之一。本研究首次尝试将群文阅读这种新兴的阅读教学方式与传统的单本阅读教学方式进行对比研究，主要从提升学生阅读兴趣的效能方面进行分析与探讨。实验涉及我国中西部5个省市、6个区县共计1 231名中小学生，并使用MIMIC模型，在有效控制测量误差的基础上，对实证数据进行了量化建模与分析，通过分析发现，群文阅读教学对激发学生阅读的“情境兴趣”有更加显著的作用，具体表现为对学生阅读注意力、情感体验、探索意愿、价值感知的影响更大，同时也验证了Knogler提出的“情境兴趣模型”在阅读教学领域的适用性，从而为进一步推进我国中小学阅读课程教学改革提供了科学的数据支撑。因此，为提升中小学生阅读素养，在阅读教学中引入群文阅读这一新兴的教学方式，具有重要的实践价值和现实意义。     

Parametrizing the Kepler exoplanet period-radius distribution with the bivariate normal inverse Gaussian distribution

This paper presents a simple and robust method for obtaining a comprehensive understanding of the joint period and radius distribution in Kepler exoplanets. The proposed method is based on particle swarm optimization and bivariate Normal Inverse Gaussian distribution. Furthermore, in the construction of the probability density function, this study selects planet-host stars with the GK-type. The injecting approach is also employed to solve the survey completeness of sample. The resulting occurrence rate of Earth analogs is 0.025 with a 95% bootstrap confidence interval between 0.023 and 0.032.     

Smoothed bootstrap bandwidth selection for nonparametric hazard rate estimation

A smoothed bootstrap method is presented for the purpose of bandwidth selection in nonparametric hazard rate estimation for iid data. In this context, two new bootstrap bandwidth selectors are established based on the exact expression of the bootstrap version of the mean integrated squared error of some approximations of the kernel hazard rate estimator. This is very useful since Monte Carlo approximation is no longer needed for the implementation of the two bootstrap selectors. A simulation study is carried out in order to show the empirical performance of the new bootstrap bandwidths and to compare them with other existing selectors. The methods are illustrated by applying them to a diabetes data set.     

Generational conflict and provisions for the elderly in Hong Kong: The relevance of position‐based interest and values

Respect for the elderly and hence the associated rights support a generational contract. Nevertheless, the case of the recent debate on the universal retirement scheme in Hong Kong has raised concerns about its strength. We identify relevant items from the sixth wave of the World Values Survey to explore the orientations of different generations toward others. The analysis shows differences between younger and older generations. Regression analyses show that values are not significant in explaining the differences, but various positions, including sex, marital status, and education, and perceptions of the elderly are relevant. Such differences across generations might weaken the generational contract and potentially engender conflicts as shown in the recent debate about the retirement scheme. We suggest short‐ and long‐term interest calculations, informed by their positions, play a more significant role in policy discussions and decisions, rather than simply appealing to values.     

Uniform consistency rate of kNN regression estimation for functional time series data

In this paper, we investigate the k-nearest neighbours (kNN) estimation of nonparametric regression model for strong mixing functional time series data. More precisely, we establish the uniform almost complete convergence rate of the kNN estimator under some mild conditions. Furthermore, a simulation study and an empirical application to the real data analysis of sea surface temperature (SST) are carried out to illustrate the finite sample performances and the usefulness of the kNN approach.     

异质性技术视角下中国高技术制造业创新效率研究

目前，学术界对选取何种风险调整贴现率期限结构还存在争议，导致对同类投资项目得 出不同的管理指引意见． 针对这一争议，本文通过划分资本产出方式， 寻找影响贴现率结构的 主要因素． 研究表明，不确定的宏观经济产出和项目非系统风险共同影响风险溢价系数， 同时 风险溢价系数决定贴现率期限结构． 其中，当风险溢价系数大于某确定阈值， 贴现率随时间递 增; 其余情况表现为递减．