Building a statistical model to predict reactor temperatures

This paper describes the various stages in building a statistical model to predict temperatures in the core of a reactor, and compares the benefits of this model with those of a physical model. We give a brief background to this study and the applications of the model to rapid online monitoring and safe operation of the reactor. We describe the methods, of correlation and two dimensional spectral analysis, which we use to identify the effects that are incorporated in a spatial regression model for the measured temperatures. These effects are related to the age of the reactor fuel and the spatial geometry of the reactor. A remaining component of the temperature variation is a slowly varying temperature surface modelled by smooth functions with constrained coefficients. We assess the accuracy of the model for interpolating temperatures throughout the reactor, when measurements are available only at a reduced set of spatial locations, as is the case in most reactors. Further possible improvements to the model are discussed.     

WHITE ENROLLMENT IN NONPUBLIC SCHOOLS, PUBLIC SCHOOL RACIAL COMPOSITION, AND STUDENT PERFORMANCE

This research note presents preliminary research into the relationship between the racial composition of public schools in school districts and the percentages of white students in nonpublic schools in those districts. Specifically, we ask two questions: Is the enrollment of whites in non‐public schools associated with minority predominance in public schools? Is there an association between the enrollment of whites outside of the public school system and the academic performance of students in the public school system? Using two‐ and three‐level hierarchical linear models, we find that school districts that have more whites in nonpublic schools tend to contain public schools with larger percentages of minority students. Further, at both the school and individual levels, achievement test scores tend to be lower in districts in which white students tend to be enrolled outside of the public school system. In addition, the achievement gap between white and minority students tends to be greater in districts with relatively more students in nonpublic schools. These findings are consistent with the argument that the withdrawal of white students from the public school system is negatively related to academic achievement because it tends to concentrate minority students in public schools.     

Leadership research and cognitive neuroscience: The state of this union

Advances in cognitive neuroscience and other approaches to understanding human behavior from a biological standpoint are only now beginning to filter into leadership research. The purpose of this introduction to the Leadership Quarterly Special Issue on the Biology of Leadership is to outline the organizational cognitive neuroscience approach to leadership research, and show how such an approach can fruitfully inform both leadership and neuroscientific research. Indeed, we advance the view that the further application of cognitive neuroscientific techniques to leadership research will pay great dividends in our understanding of effective leadership behaviors and as such, a future symbiosis between the two fields is a necessity.     

The Nature of Social Pasts and Their Use as Foundations for Situated Action

In this paper social pasts are considered to be foundations of everyday interpersonal life, including everyday situated action. We distinguish social pasts from culture by noting that the former involves recognition of specific joint acts and social placements while the latter involves recognition of ties to acts and placements in general. We further distinguish shared pasts–which refer to specific and previous joint acts or social placements that interactors constructed together–from common pasts–which refer to specific and previous joint acts or social placements that interactors constructed with others. We assess the importance of using either common or shared pasts in the course of completing and simplifying complex and everyday transactions so as to create an appearance of routine-ness in relation to constructing these acts.     

The right to be different: Multiculturalism and the racialization of scandinavian welfare politics; The case of Denmark

‘Multiculturalism’ as an influential ideology for structuring ethnic relations has become exposed to increasing critique also in the Scandinavian context. The paper discusses a racialized political debate, legislation, and institutional practices, taking Denmark as the prime example. An increasingly ‘dual welfare’ is becoming legitimized through a hegemonic culturalized language, consistently interpreting ‘the right to be different’ as ‘being different’, and ‘being different’ as being ‘non‐integrated’. In a society where public debate on ethnic and racial discrimination is less than rudimentary, tolerant claims of multiculturalist relativism are effectively turned upside down in the service of neo‐racism, the preachings of which are imperceptibly becoming adopted as the conventional wisdom. This calls for a discussion on ‘politics of recognition’ which brings the debate on the universalism and particularity out of the abstract, while focusing on the vicissitudes of contemporary democracy in a changing welfare state.     

Business Interest Group Power and Temporary Assistance to Needy Families*

Objectives. Our aim is to test the influence of business interest groups on Temporary Assistance to Needy Families (TANF) policy at the state level. Methods. We use the state TANF guarantee, the length of time recipients have before they lose their benefits, and the existence of a “family cap” as dependent variables in three models. Each of the models tests business interest group power and several other measures that represent possible influences on the dependent variable. Results. We find that business interest group power is significantly related to both the generosity of the TANF guarantee and to TANF time limits. However, it is not related to the presence of the family cap in state TANF policy. Conclusions. The evidence we found is consistent with the idea that those state TANF policies that are most intimately related to business interests are just those policies that are most affected by business group influence. States' TANF policies regarding maximum benefit and time limits both have a direct impact on wealth redistribution and labor‐market behavior. On the other hand, business interest groups do not seem to have much influence on the presence of TANF family caps, policies that are arguably less the concern of business interest groups, and more connected to public attitudes toward families and children.     

POPAN-4: enhancements to a system for the analysis of mark-recapture data from open populations

We describe recent developments in the POPAN system for the analysis of mark-recapture data from Jolly-Seber type experiments. The previous versions (POPAN-3 for SUN/OS workstations and POPAN-PC for IBM-PC running DOS or Windows) included general statistics gathering and testing procedures, a wide range of analysis options for estimating population abundance, survival and birth parameters, and a general simulation capability. POPAN-4 adds a very general procedure for fitting constrained models based on a new unified theory for Jolly-Seber models. Users can impose constraints on capture, survival and birth rates over time and/or across attribute groups (e.g. sex or age groups) and can model these rates using covariate models involving auxiliary variables (e.g. sampling effort).     

慢市一种全新的舒适生活

或许,你听过或看过“慢活”这个名词,却不了解“慢活”是什么?它是全球正刮着的一股新风潮,有一群人极力鼓倡、推行着慢食、慢工、慢动、慢性、慢疗和慢闲运动,以一种正常而平衡的速度生活着……