[1] Data assimilation techniques provide algorithms that allow for blending of incomplete and inaccurate data with physics-based dynamic models to reconstruct the electron phase space density (PSD) in the radiation belts. In this study, we perform reanalyses of the radial PSD profile using two independent data sources from the nearly equatorial CRRES Medium Electron A (MEA) observations and the polar-orbiting Akebono Radiation Monitor (RDM) measurements for a 50-day period from 18 August to 6 October 1990. We utilize the University of California, Los Angeles, One-Dimensional Versatile Electron Radiation Belt (UCLA 1-D VERB) code and a Kalman filtering approach. Comparison of the reanalyses obtained independently using the CRRES MEA and Akebono RDM measurements shows that the dynamics of the PSD can be accurately reconstructed using Kalman filtering even when available data are sparse, inaccurate, and contaminated by random errors. The reanalyses exhibit similarities in the locations and magnitudes of peaks in radial profiles of PSD and the rate and radial extent of the dropouts during storms. This study shows that when unidirectional data are not available, pitch angle averaged flux measurements can be used to infer the long-term behavior (climatology) of the radiation belts. The methodology of obtaining PSD from pitch angle averaged and unidirectional fluxes using the Tsyganenko and Stern (1996) magnetic field model is described in detail.

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This study is a descriptive study to investigate relevance of dry eye symptoms and physical symptoms of university students using smartphones and to identify the factors affecting dry eye symptoms. We collected data from university students in C province of Korea on March 3-29, 2016. They responded questionnaires of general characteristics, physical symptoms, and eye dry symptoms. 315 questionnaires were collected and 310 questionnaires were analyzed except for the incomplete one. Data were analyzed using t-test, one-way ANOVA, Scheffe test, Descriptive analysis, Pearson's correlation coefficients, and multiple regression analysis. The participants' dry eye symptoms according to general characteristics showed statistically significant differences in gender (t=-3.306, p=.001), whether to wear contact lenses (t=-3.386, p=.001), smartphone use time (F=5.133, p=.002), and computer use time (F=5.137, p=.002). We were found that 68 (21.9%) were normal, 80 (25.8%) were mild, 58 (18.7%) were moderate and 104 (33.5%) were severe, and that 78.1% of 310 students had dry eye. And OSDI (Ocular Surface Disease Index) showed a significant correlation with turtle neck syndrome (r=.343, p<.001), wrist tunnel syndrome(r=.252, p<.001), and eye fatigue(r=.681, p<.001), and OSDI was significantly affected by eye fatigue (β=.668, t=16.042, p<.001),

Conceptual understanding has been emphasized in the national curriculum and principles and standards across nations as it is the key in mathematical learning. However, mathematics instruction in classrooms often relies on rote memorization of mathematical rules and formulae without conceptual connections. This study considers the concreteness fading instruction strategy—starting with physical activities with manipulatives and gradually fading concreteness to access abstract concepts and representations—as a promising and sustainable instructional model for supporting students in accessing conceptual understanding in mathematics classrooms. The results from the case study support the validity of the concreteness fading framework in providing specific instructional strategies in each phase of concept development. This study implies the development of sustainable teacher education and professional development by providing specific instructional strategies for conceptual understanding.

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