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The purpose of the study reported in this article is to empirically examine passage-related local item dependence (LID) by using an IRT (item response theory) based LID index called Q3 in an EFL reading comprehension test, with a special focus on item types as a potentially competing source of LID with passages. In this article, definitions and causes of LID and major LID detection methods including Q3 statistics are reviewed along with the two potential sources of LID in EFL reading assessment. Scored item responses of 1857 Korean high school students to a 40-item EFL (English as a Foreign Language) reading comprehension test were analysed by using MULTILOG and IRTNEW. It was found that positive LID exists among items within passages, but no item-type-related LID was confirmed in the study. Subsequent content analysis of an item pair with an extreme Q3 value has also provided some insights into the item characteristics that may exacerbate passage-related LID. These findings shed important light on the nature of passage-related LID, psychometric dimensionality, and measurement construct of the EFL reading comprehension test.

Hubble Space Telescope (HST) photometry is providing an extensive analysis of globular clusters (GCs). In particular, the pseudo-two-colour diagram dubbed 'chromosome map (ChM)' allowed to detect and characterize their multiple populations with unprecedented detail. The main limitation of these studies is the small field of view of HST , which makes it challenging to investigate some important aspects of the multiple populations, such as their spatial distributions and the internal kinematics in the outermost cluster regions. To overcome this limitation, we analyse state-of-art wide-field photometry of 43 GCs obtained from ground-based facilities. We derived high-resolution reddening maps and corrected the photometry for differential reddening when needed. We use photometry in the U, B , and I bands to introduce the Δ c U, B, I versus ΔB, I ChM of red-giant branch (RGB) and asymptotic-giant branch stars. We demonstrate that this ChM, which is built with wide-band ground-based photometry, is an efficient tool to identify first- and second-generation stars (1G and 2G) over a wide field of view. To illustrate its potential, we derive the radial distribution of multiple populations in NGC 288 and infer their chemical composition. We present the ChMs of RGB stars in 29 GCs and detect a significant degree of variety. The fraction of 1G and 2G stars, the number of subpopulations, and the extension of the ChMs significantly change from one cluster to another. Moreover, the metal-poor and metal-rich stars of Type II GCs define distinct sequences in the ChM. We confirm the presence of extended 1G sequences. [ABSTRACT FROM AUTHOR]

Transparent conductors are essential for many optoelectronic applications, and economically viable replacement for the industry standard transparent conductor, indium tin oxide, is in dire need. Electronic structure calculations are performed to confirm that La doping in a band insulator SrTiO3 provides carriers in the conduction band without generating in-gap states and thus La doped SrTiO3 would retain good optical transparency. To realize the computational results, we synthesize La doped SrTiO3 in thin film form and characterize the films. It is demonstrated that 10% La doped SrTiO3 thin films on SrLaAlO4 (001) substrates are indeed transparent conductors with sheet resistance RS ∼ 60 Ω/□ and 80% transmission in the visible wavelength range at room temperature. [ABSTRACT FROM AUTHOR]

A multiple regression method (MRM) is used for the first time with Ozone Monitoring Instrument (OMI) and Moderate Resolution Imaging Spectroradiometer (MODIS) data to estimate formaldehyde (HCHO) column over Asia in two categorized areas: (1) anthropogenic areas in East Asia (east-central China, Beijing, Seoul, and Tokyo) and (2) biogenic and pyrogenic areas (Indochina and South Borneo). In order to determine the multiple regression equations (MREs) for each study area, monthly mean and daily values of Nitrogen dioxide (NO2) level, land surface temperature (LST), enhanced vegetation index (EVI), and fire radiative power (FRP) from 2005 to 2006 were used as independent variable candidates and monthly mean and daily HCHO measured by OMI (HCHOOMI) for the same period was used as the dependent variable. The MREs estimated HCHO (HCHOMRM) with inputs of independent variable data for from 2005 to 2006 whereas they estimated HCHO (HCHOVAL) with inputs of independent variable data in 2007. The agreement between HCHOOMI and HCHOVAL is comparable with that between HCHOOMI and HCHOMRM in both monthly and daily scale. The average correlation coefficient, slope, mean bias, mean absolute error, root mean square error, and percent difference between monthly HCHOOMI and monthly HCHOVAL (between daily HCHOOMI and daily HCHOMRM) are 0.89 (0.58), 0.77 (0.34), -0.82 × 1015 molecules cm-2 (-0.91 × 1015 molecules cm-2), 1.28 × 1015 molecules cm-2 (3.01 × 1015 molecules cm-2), 1.75 × 1015 molecules cm-2 (4.32 × 1015 molecules cm-2), 10.2% (24.1%). MRM can be a useful tool to provide HCHO in certain area in Asia. [ABSTRACT FROM AUTHOR]

In this study, (Na,K,Li)(Nb,Sb,Ta)O3 ceramics substituted with (Sr,Ca)ZrO3 by conventional solid state method were manufactured and their dielectric and piezoelectric properties were investigated. The (Na,K,Li)(Nb,Sb,Ta)O3 ceramics substituted with 0.01 (Sr,Ca)ZrO3 showed excellent piezoelectric properties. The density(ρ), piezoelectric constant(d33), and the piezoelectric voltage constant (g33), planar piezoelectric coupling coefficient(kp), mechanical quality factor(Qm), and dielectric constant(εr) showed the excellent values of 4.55 g/cm3, 254pC/N, 26.17(×10−3 Vm/N) 0.46, 156, and 1096, respectively. The multilayer piezoelectric energy harvester was fabricated using the above composition ceramics by tape casting methods. When driving frequency was 80 Hz under gravity acceleration 1G, the multilayer energy harvester with the size of 30 mm ×3 mm ×1 mm showed the maximum output voltage of 1.1V at no load. And the maximum output power 3.28 µW of the harvester was also shown at the 50 Hz under gravity acceleration 1G. [ABSTRACT FROM AUTHOR]