4,589 research outputs found
A note on q-analogue of Boole polynomials
In this paper, we consider the q-extensions of Boole polynomials. From those
polynomials, we derive some new and interesting properties and identities
related to special polynomials.Comment: 11 page
Barnes-type Daehee polynomials
In this paper, we consider Barnes-type Daehee polynomials of the first kind
and of the second kind. From the properties of Sheffer sequences of these
polynomials arising from umbral calculus, we derive new and interesting
identities.Comment: 34 page
Linear differential equations for families of polynomials
Abstract In this paper, we present linear differential equations for the generating functions of the Poisson-Charlier, actuarial, and Meixner polynomials. Also, we give an application for each case
Demographic and Socioeconomic Influences on Sleep Patterns among Adolescent Students
Although proper sleep is an important topic in adolescent health, little is known about the sleep patterns of adolescents from a longitudinal and non-Western perspective. To fill this gap, the present research conducted a longitudinal study of the impact of demographic and socioeconomic factors on sleep patterns among Korean adolescent students. The relationship could positively or negatively affect sleep. Therefore, it is important to understand which demographic and socioeconomic factors are related to sleep patterns. This study used nationally representative panel data from the Korean Children and Youth Panel Survey. A series of descriptive analyses were conducted to provide overall characteristics of the sample. Furthermore, mixed effect regression analysis techniques were employed to test the relationship between demographic and socioeconomic factors and sleep patterns. Paternal employment status was associated with adolescent sleep patterns, while maternal employment status was not. Adolescents with both parents working compared to adolescents with one parent or none working showed different sleep patterns on weekdays but not on weekends. Both parents possessing college degrees, household income, living in an urban area, and family type were associated with adolescent sleep pattern indicators to varying degrees. Some of these associations varied according to adolescent sex. This study provides insight into the impact of demographic and socioeconomic factors on weekend and weekday sleep patterns among adolescent students by sex. These findings provide information for the promotion of healthy sleep in adolescents by addressing demographic and socioeconomic factors
Relationships between Sleep Patterns, Health Risk Behaviors, and Health Outcomes among School-Based Population of Adolescents:A Panel Analysis of the Korean Children and Youth Panel Survey
Sleep patterns among adolescents are related to health outcomes and health risk behaviors. This study aimed to describe sleep patterns of Korean adolescents and to find the association between sleep patterns and health risk behaviors and health outcomes. Using the junior high school students' panel data (n = 2351, 12-15 years old) from the Korean Children and Youth Panel Survey, this study described the sleep patterns operationalized as rising time, bedtime, and sleep duration both on weekdays and weekends. The relationships of sleep patterns with health outcomes and/or health risk behaviors were tested using mixed effect linear regression for continuous health variables and using mixed effect logit regression for binary health variables. Obesity status, the number of chronic symptoms, self-rated health status, smoking, and alcohol consumption were associated with rising time on weekdays after controlling for gender, living area, and housing type. The same set of variables except for the number of chronic symptoms were associated with bedtime during the weekdays. Sleep duration during the weekdays was associated with obesity status, smoking, and alcohol consumption. Similar patterns of association between sleep pattern variables during the weekends and health-related outcome variables were found, but were less obvious than those for weekdays. Significant relationships between sleep patterns and various health-related variables were found among adolescents in Korea. The results from this study indicate that helping adolescents change their sleeping times as necessary to ensure adequate sleep should be considered important in diminishing health risk behaviors and promoting positive health outcomes
Particulate counter electrode system for enhanced light harvesting in dye-sensitized solar cells
A particulate counter electrode with photo scattering and redox catalytic properties is applied to dye sensitized solar cells (DSSCs) in order to improve photo conversion efficiency and simplify the assembly process. Our particulate counter electrode acts as both a photo reflecting layer and a catalyst for reduction of electrolyte. The reflective and catalytic properties of the electrode are investigated through optical and electrochemical analysis, respectively. A short circuit current density enhancement is observed in the DSSCs without the need to add an additional reflecting layer to the electrode. This leads to a simplified assembly process. (C) 2013 Optical Society of Americ
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