The approximate f-core and the utopia payoff for infinite assignment games

Assignment problems where both sets of agents are countably infinite, the so-called infinite assignment problems, are studied as well as the related assignment games. Further, two solutions for these games are studied. The first one is the approximate f-core for games with a finite value. This particular solution takes into account that due to organisational limitations only finite groups of agents can protest against proposals of profit distributions. Second, we study the utopia payoff, the perfect proposal in which each agent receives the maximal amount he can get. \u

An Evaluation Study of Site-Based Managed Behaviors in a Rural Utah School

Site-based management (SBM) in schools can trace its roots back to two phenomena, citizen\u27s movements in large cities such as New York in the late 1960s and decentralization efforts of business in the 1970s. Both were done in the belief that achieving a better result can be done 11 through decisions made by the people closest to the process. Site-based management programs are diverse. Some stress one aspect, the restructuring of the school administration and program to affect achievement. Other schools stress a second aspect, the empowerment of teachers and stakeholders to make administrative decisions. Whichever emphasis chosen, several changes must occur for school management to move from the central office to the local school. These changes are evolutionary, taking 10-15 years. An evaluation study in a northern rural Utah school that has been involved with site-based management since 1990 allows for a context to understand the changes that might occur, namely, (a) the relinquishment of central school district authority; (b) the assumption of authority by the local school; ( c) the assumption of accountability for student achievement; ( d) the development of sensitivity between school and community; and (e) the development of consensus among school stakeholders. An instrument was developed for the evaluation, the Site-Based Management Progress Check. The instrument used items covering the agents and activities that would be present as these five changes occur. Additionally, the largest portion of the progress check was based on the goals in the school. As respondents showed more agreement concerning which goals were chosen and achieved, an inference was made that greater progress had occurred toward the team activity necessary for local school management. The data were provided by 100% of the lower-elementary teachers; upper-elementary teachers, however, were poorly represented, restricting data generalizability. The study indicated that, despite its 7-year involvement with site-based management, the school was still at an early stage of development with no change in district authority and no use of stakeholder groups to monitor goals. The school did have a wide base of teacher leadership. Slow progress seems to be related to lack of knowledge of SBM processes

Evidence for entanglement at high temperatures in an engineered molecular magnet

The molecular compound [Fe$_{2}$($\mu_{2}$-oxo)(C$_{3}$H$_{4}$N$_{2}$)$_{6}$(C$_{2}$O$_{4}$)$_{2}$] was designed and synthesized for the first time and its structure was determined using single-crystal X-ray diffraction. The magnetic susceptibility of this compound was measured from 2 to 300 K. The analysis of the susceptibility data using protocols developed for other spin singlet ground-state systems indicates that the quantum entanglement would remain at temperatures up to 732 K, significantly above the highest entanglement temperature reported to date. The large gap between the ground state and the first-excited state (282 K) suggests that the spin system may be somewhat immune to decohering mechanisms. Our measurements strongly suggest that molecular magnets are promising candidate platforms for quantum information processing

Anomalous Roughening in Experiments of Interfaces in Hele-Shaw Flows with Strong Quenched Disorder

We report experimental evidences of anomalous kinetic roughening in the stable displacement of an oil-air interface in a Hele-Shaw cell with strong quenched disorder. The disorder consists on a random modulation of the gap spacing transverse to the growth direction (tracks). We have performed experiments varying average interface velocity and gap spacing, and measured the scaling exponents. We have obtained beta=0.50, beta*=0.25, alpha=1.0, alpha_l=0.5, and z=2. When there is no fluid injection, the interface is driven solely by capillary forces, and a higher value of beta around beta=0.65 is measured. The presence of multiscaling and the particular morphology of the interfaces, characterized by high slopes that follow a L\'evy distribution, confirms the existence of anomalous scaling. From a detailed study of the motion of the oil--air interface we show that the anomaly is a consequence of different local velocities over tracks plus the coupling in the motion between neighboring tracks. The anomaly disappears at high interface velocities, weak capillary forces, or when the disorder is not sufficiently persistent in the growth direction. We have also observed the absence of scaling when the disorder is very strong or when a regular modulation of the gap spacing is introduced.Comment: 14 pages, 17 figure

Análise da distribuição da freqüência mensal de precipitação para a sub-região da Nhecolândia, Pantanal, Mato Grosso do Sul, Brasil.

Durante o período 1977 a 2000, foram analisados dados diários de precipitação coletados na Estação Climatológica de Nhumirim (latitude 18o59'19.86 S, longitude 56o37'21.74 W, altitude 97 m), localizada na fazenda Nhumirim, sub-região da Nhecolândia, Pantanal, MS. Os objetivos deste trabalho foram verificar o intervalo de precipitação que ocorreu com maior freqüência na sub-região da Nhecolândia e em que mês ocorreu. Foi feita uma classificação da intensidade de precipitação ocorrida de acordo com o intervalo de classe nos quais os valores de precipitação foram divididos. Calculou-se o percentual da freqüência que cada intervalo apresentou em relação ao total de dias com ocorrência de precipitação. O resultado mostrou que o intervalo de precipitação com maior freqüência (cerca de 26%) em todos os meses foi o intervalo de [0,1 mm; 5 mm], o qual foi classificado como "intensidade de precipitação muito fraca".bitstream/item/37418/1/BP34.pd

Environmental Tobacco Smoke Exposure in Relation to Family Characteristics, Stressors and Chemical Co-Exposures in California Girls.

Childhood environmental tobacco smoke (ETS) exposure is a risk factor for adverse health outcomes and may disproportionately burden lower socioeconomic status groups, exacerbating health disparities. We explored associations of demographic factors, stressful life events, and chemical co-exposures, with cotinine levels, among girls in the CYGNET Study. Data were collected from families of girls aged 6-8 years old in Northern California, through clinic exams, questionnaires and biospecimens (n = 421). Linear regression and factor analysis were conducted to explore predictors of urinary cotinine and co-exposure body burdens, respectively. In unadjusted models, geometric mean cotinine concentrations were higher among Black (0.59 ug/g creatinine) than non-Hispanic white (0.27), Asian (0.32), or Hispanic (0.34) participants. Following adjustment, living in a rented home, lower primary caregiver education, and lack of two biologic parents in the home were associated with higher cotinine concentrations. Girls who experienced parental separation or unemployment in the family had higher unadjusted cotinine concentrations. Higher cotinine was also associated with higher polybrominated diphenyl ether and metals concentrations. Our findings have environmental justice implications as Black and socio-economically disadvantaged young girls experienced higher ETS exposure, also associated with higher exposure to other chemicals. Efforts to reduce ETS and co-exposures should account for other disparity-related factors

Análise das condições climáticas em 2000 na sub-região da Nhecolândia, Pantanal, Mato Grosso do Sul, Brasil.

Este trabalho teve como objetivo contribuir para o estudo das condições climáticas na sub-região da Nhecolândia, Pantanal/MS, organizando e difundindo informações climatológicas ocorridas durante o ano de 2000, comparando-as com a normal climatológica. Foi analisado o comportamento dos elementos climáticos no ano de 2000 em relação a "normal climatológica", calculada a partir de 23 anos de observação, referentes ao período de 1977 a 1999. Para o cálculo do balanço hídrico, aplicou-se o método de Thornthwaite & Mather (1955), para uma retenção hídrica de 50 mm. O total anual de precipitação pluvial em 2000 (1.433,4 mm) foi superior ao da normal climatológica (1.175,0 mm), com distribuição mensal bastante diferente do padrão esperado. A temperatura média anual do ar (25,0oC), temperatura média anual das máximas(31,6oC) e temperatura média anual das mínimas (20,3oC), foram ligeiramente inferiores à média da normal, que foi de 25,4oC, 31,7oC e 20,4oC, respectivamente. O total anual de evaporação do ar foi de 1.862,2mm, com excedente de 329,6mm em relação à normal (1.532,6mm). A média anual de umidade relativa do ar (78,2%) foi inferior à normal (81,7%). O total de horas de insolação (2.506,0 horas) foi superior àquele determinado para a normal (2.420,6 horas). As condições termopluviais da região apresentaram evapotranspiração de referência de 1.477,2 mm, com deficiência e excedente hídrico anual de 339,4 mm e 295,8 mm, respectivamente.bitstream/item/37422/1/BP30.pd