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81.
82.
J. M. G. Salmerón G. Aparicio L. G. Casado I. García E. M. T. Hendrix B. G.-Tóth 《Journal of Combinatorial Optimization》2017,33(2):389-402
In several areas like global optimization using branch-and-bound methods for mixture design, the unit n-simplex is refined by longest edge bisection (LEB). This process provides a binary search tree. For \(n>2\), simplices appearing during the refinement process can have more than one longest edge (LE). The size of the resulting binary tree depends on the specific sequence of bisected longest edges. The questions are how to calculate the size of one of the smallest binary trees generated by LEB and how to find the corresponding sequence of LEs to bisect, which can be represented by a set of LE indices. Algorithms answering these questions are presented here. We focus on sets of LE indices that are repeated at a level of the binary tree. A set of LEs was presented in Aparicio et al. (Informatica 26(1):17–32, 2015), for \(n=3\). An additional question is whether this set is the best one under the so-called \(m_k\)-valid condition. 相似文献
83.
Alex I. Thompson 《Symbolic Interaction》2014,37(4):608-610
84.
Musicians have long been hampered by the challenge in turning sheet music while their hands are occupied playing an instrument. The sight of a human page turner assisting a pianist during a performance, for instance, is not uncommon. This need for a page turning solution is no less acute during practice sessions, which account for the vast majority of playing time. Despite widespread appreciation of the problem, there have been virtually no robust and affordable products to assist the musician. Recent progress in assistive technology and electronic reading devices offers promising solutions to this long-standing problem. The objective of this paper is to survey the technology landscape and assess the benefits and drawbacks of page turning solutions for musicians. A full range of mechanical and digital page turning products are reviewed. 相似文献
85.
Ana I. Moro-Egido 《Journal of Family and Economic Issues》2012,33(1):11-23
This paper explores how mothers’ allocation of types of time with children and the determinants of this allocation have changed
during 1981–1997 in the United States, using Time Use Longitudinal Panel Study and Family Interaction, Social Capital and
Trends in Time Use. Data reveal that active time with children has increased for the case of educated working mothers with young children. Estimations also provide evidence
that although different uses of time are substitutes; active time is less sensitive than passive. Moreover, the relationship between active and passive time with children has changed over time. 相似文献
86.
Alisson F. Barbieri Edson Domingues Bernardo L. Queiroz Ricardo M. Ruiz José I. Rigotti José A. M. Carvalho Marco F. Resende 《Population and environment》2010,31(5):344-370
This research contributes to an understanding of the relationship between climate change, economic impacts and migration.
We model the long-term relationship (up to 45 years of projection) between demographic dynamics—particularly migration—driven
by changes in the performance of the economy due to climate changes in the Northeast region of Brazil. The region is of particular
relevance to the study of climate change impacts given its large human population (28% of Brazil’s population) and high levels
of impoverishment, having an extensive semi-dry area which will be severely impacted by growing temperatures. Ultimately,
the integrated model generates state- and municipal-level migration scenarios based on climate change impacts on the primary
economic sectors and their articulations with other sectors. Results suggest that the predicted climate changes will impact
severely the agriculture sector in the region, acting as a potential migration push factor to other regions in the country.
Finally, we discuss how the increased vulnerability of some groups, particularly migrants, can be factored into Brazilian
public policy and planning. 相似文献
87.
This paper examines how full-time or part-time status affects students’ level of satisfaction with their degree programs.
For our analysis, we obtained data from a survey of graduate students. The survey was conducted at a public university in
Spain from 2001 to 2004. The decision to undertake paid employment while studying emerges as one of the key determinants of
student satisfaction. In particular, our findings indicate that students who hold a part-time job while studying are more
likely to express less satisfaction with their college experience. 相似文献
88.
Amber A. Remble Maria I. Marshall Roman Keeney 《Journal of Family and Economic Issues》2014,35(3):411-422
This study focused on the lifecycle income objective of business-owning (farm and nonfarm) households. We hypothesized that the complex relationship between household and business management decisions had the potential to challenge predictions from standard household savings theory. Specifically, we tested for differences in saving behavior of these entrepreneurial households relative to the average US household. A limited dependent variable model was performed, keying in on the saving behavior and ability of household respondents in the Survey of Consumer Finances for 2007. The estimation results indicated that, along with standard demographic influences of savings models, households owning a farm or nonfarm business had a significantly higher likelihood of maintaining private saving in a given year. Our results highlight the necessity for future research on household saving behavior to account for the differing objectives and choice sets faced by households that own businesses when conducting analyses of household saving. 相似文献
89.
Kristy Parkinson Joseph Price Kosali I. Simon Sharon Tennyson 《Review of Economics of the Household》2014,12(4):771-790
We examine how use of antidepressant medications is influenced by Food and Drug Administration (FDA) warnings about the increased risk of suicidality associated with pediatric antidepressant use. With individual-level data on antidepressant use from the Medical Expenditure Panel Survey, we consider whether consumer responses to FDA warnings differ among targeted (children) and non-targeted (adult) age-groups. Because the warning labels specifically mentioned new users, we examine separately the effects of the warnings on initiations of antidepressant therapy and on continued use of antidepressants. We find evidence consistent with reduced initiation of antidepressant use among the intended population of children, and that usage among children with more highly educated parents responded earlier to FDA information. However, we also find spillover effects of reduced initiation among the non-targeted population of adults. Overall, our results indicate that the FDA warning may have led consumers to perceive risks beyond those specifically mentioned. 相似文献
90.
Decision support for managers and policy makers, such as required in planning and evaluation efforts, often requires ad hoc behavioral modeling to account for context-specific phenomena and to handle data limitations. This paper introduces a systematic approach useful for meeting these requirements in which time-varying parameter estimation plays an important role. A case study evaluating the impacts of public policy actions on residential natural gas conservation illustrates the approach. 相似文献