Models of sky radiance distribution and sky luminance distribution

The aim of this research work is to propose sky radiance and luminance distribution models for all sky conditions from clear sky to overcast sky. The classification method of sky conditions is examined. Clear sky index is defined based on the global irradiance. Cloudless index is defined based on the global irradiance and the diffuse irradiance. The sky conditions are classified according to both indices. The data of the average sky radiance (luminance) distributions are obtained based on the classified sky conditions. The average relative sky radiance distributions are compared with the average relative sky luminance distributions. It has been confirmed that both radiance/luminance distributions can be shown by the same equation.An equation that shows the relative sky radiance (luminance) distribution for all sky conditions and equations that show the zenith radiance and the zenith luminance are obtained. The absolute value of the sky radiance (luminance) distribution is shown by multiplying the relative sky radiance (luminance) distribution and the zenith radiance (luminance). The equations to show the absolute values of the sky radiance distribution called the All Sky Model-R and the sky luminance distribution called the All Sky Model-L are proposed.Both models are compared with the previous models based on the measurement distributions concerning the region of sky vault and the sky conditions and good results are obtained. In addition, the vertical irradiance and illuminance calculated by the proposed models and the previous models are compared with the measurements, and the proposed models are confirmed their accuracy.     

Epidemiological comparisons of problems and positive qualities reported by adolescents in 24 countries.

In this study, the authors compared ratings of behavioral and emotional problems and positive qualities on the Youth Self-Report (T. M. Achenbach & L. A. Rescorla, 2001) by adolescents in general population samples from 24 countries (N = 27,206). For problem scales, country effect sizes (ESs) ranged from 3% to 9%, whereas those for gender and age ranged from less than 1% to 2%. Scores were significantly higher for girls than for boys on Internalizing Problems and significantly higher for boys than for girls on Externalizing Problems. Bicountry correlations for mean problem item scores averaged .69. For Total Problems, 17 of 24 countries scored within one standard deviation of the overall mean of 35.3. In the 19 countries for which parent ratings were also available, the mean of 20.5 for parent ratings was far lower than the self-report mean of 34.0 in the same 19 countries (d = 2.5). Results indicate considerable consistency across 24 countries in adolescents' self-reported problems but less consistency for positive qualities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of Crystal-Axis Orientation on Resonance Mode of BaTiO3 Ceramics

BaTiO₃ ceramics were fabricated by sintering a mixture of fibrous and commercial powders, and the effects of crystal-axis orientation on the resonance characteristics of the poled specimens was investigated. Resonance in the radial direction was observed only for the fibrous BaTiO₃ ceramic disk. The degree of c -axis orientation of the sintered compact decreased with an increase in the initial amount of the commercial powder, and the decrease in the degree of orientation caused the appearance of the resonance in the thickness direction.     

Effect of Metal Ion Addition in a Ni Supported Ga2O3 Photocatalyst on the Photocatalytic Overall Splitting of H2O

The effects of the addition of a metal ion in a Ni supported Ga₂O₃ photocatalyst on the photocatalytic overall splitting of H₂O were investigated. The addition of Ca, Cr, Zn, Sr, Ba and Ta ions were effective in improving the photocatalytic activity. Particularly, the addition of the Zn ion improved the photocatalytic activity remarkably. The states of the photocatalyst after the addition of Zn ion are discussed.     

White polymer light emitting diodes with multi-layer device structure

White polymer light emitting diodes (WPLEDs) were fabricated with multi-layer device structure using crosslinked poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene] (MEHPPV) as a red emitting layer (EML) and crosslinked poly[(9,9-dioctylfluorene-2,7-diyl)-co-(4″,4?-tertbutyl-tetraphenyl diamine-4,4′-diyl) (PF8-tTPD) as a blue emitting layer. The multi-layer device structure was realized by crosslinking the emitting layers through ultra-violet (UV) irradiation. The results showed that the crosslinking of the emitting layer affected the carrier mobility of the polymer layer and the recombination site of the electrons and holes, therefore affected the emission of the devices. The devices with crosslinked MEHPPV as red emitting layer and crosslinked PF8-tTPD as blue emitting layer showed good white emission with C.I.E. coordinates (X: 0.364; Y: 0.290) at about 500 cd/m² and showed good color stability with increasing applied voltages. UV irradiation method was found to be an effective way to crosslink the emitting layer and fabricate multi-layer polymer light emitting diodes (PLEDs).     

FTY720 Inhibits Expansion of Breast Cancer Stem Cells via PP2A Activation

Growing evidence suggests that breast cancer originates from a minor population of cancer cells termed cancer stem cells (CSCs), which can be identified by aldehyde dehydrogenase (ALDH) activity-based flow cytometry analysis. However, novel therapeutic drugs for the eradication of CSCs have not been discovered yet. Recently, drug repositioning, which finds new medical uses from existing drugs, has been expected to facilitate drug discovery. We have previously reported that sphingosine kinase 1 (SphK1) induced proliferation of breast CSCs. In the present study, we focused on the immunosuppressive agent FTY720 (also known as fingolimod or Gilenya), since FTY720 is known to be an inhibitor of SphK1. We found that FTY720 blocked both proliferation of ALDH-positive cells and formation of mammospheres. In addition, we showed that FTY720 reduced the expression of stem cell markers such as Oct3/4, Sox2 and Nanog via upregulation of protein phosphatase 2A (PP2A). These results suggest that FTY720 is an effective drug for breast CSCs in vitro.     

Evaluation of coefficients of friction in hot stamping by hot flat drawing test

The coefficient of friction in hot stamping was measured using a tribosimulator. Simulative experiments were carried out using SPHC steel and 22MnB5 steel under dry conditions. The coefficient of friction of 22MnB5 steel was higher than that of SPHC steel. The obtained coefficients of friction were effective for use in numerical simulations by finite element analysis. The obtained coefficients of friction under lubricated conditions for both steels were lower than those under dry conditions. It could be understood that the use of lubricants is effective for decreasing of the stamping load and die wear.     

Improvement of neutron startup source handling work by developing new transportation container for high-temperature engineering test reactor (HTTR)

The high-temperature engineering test reactor (HTTR) has three neutron startup sources (NSs) in the reactor core, each of which consists of ²⁵²Cf with 3.7 GBq, installed in NS holder and subsequently in a control rod guide block (CR block). The NSs are exchanged at the interval of approximately seven years. The NS holders are transported from the dealer's hot cell to the HTTR using a transportation container. The loading work of NS holders to the CR blocks is subsequently carried out in the fuel handling machine maintenance pit of HTTR.

Technical issues, which are the reduction and prevention of radiation exposure of workers and the exclusion of falling of NS holder, were extracted from the experiences in the past two exchange works of NSs to develop a safety handling procedure. Then, a new transportation container special to the NSs of HTTR was developed to solve the technical issues while keeping the cost as low as that for overhaul of conventional container.

As a result, the NS handling work using the new transportation container was safely accomplished by developing the new transportation container which can reduce the risks of radiation exposure dose of workers and exclude the falling of NS holder.     

Crystal growth and optical properties of the Nd doped LuF3 single crystals

Thirty millimeter diameter single crystal of Nd³⁺ doped LuF₃ was grown using LiF as solvent. The single phase crystallization was confirmed by the powder X-ray diffraction, and high structural perfection was demonstrated by X-ray rocking curve (XRC) measurements. FWHM of XRC for 220 reflection was 32 arcsec. No remarkable absorption due to unfavorable impurities was observed from optical absorption measurements in the VUV spectral region. The crystal showed the VUV luminescence peaking around 178 nm that is consistent with the 4f²5d-4f³ transition of Nd³⁺ ion. The luminescence intensity of Nd:LuF₃ under X-ray irradiation was significantly higher than that of reported VUV scintillators such as Nd:LaF₃ or Nd:LiLuF₄.