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Summative assessment data are rarely adapted into instructional decision making. In this project, teachers and researchers work together to identify how teachers use diagnostic data (students’ deve...

Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter.

This research is a secondary analysis with Korean students’ data collected in the TIMSS 2015 to describe the moderation effects of instructional practices on the relationships between students’ emo...

As large-scale scientific facilities develop, the klystron efficiency becomes an important issue to reduce high operating costs. We are developing high-efficiency klystrons for the Pohang Light Source-II (PLS-II) and the Pohang Accelerator Laboratory X-ray Free-Electron Laser (PAL-XFEL) at the Pohang Accelerator Laboratory (PAL). The newly developed klystrons should have the same specifications, including perveance and overall length, to replace existing ones. Under these limited conditions, we designed the klystrons based on a multi-cell output cavity to improve the power-conversion efficiency significatly. We simulated the beam-dynamics using the Field Charge Interaction (FCI) code with a MATLAB script to find the optimum design parameters for high efficiency. We have determined the design parameters, such as cell tuning frequencies, inter-cell distances, couplings between cells and the Qe of the last cell, of the multi-cell output cavity.

For a positive integer k, let $$ F (q)^{k}:= \prod_{n \geq 1} \frac{(1-q^{n})^{4k}}{(1+q^{2n})^{2k}} = \sum_{n\geq 0} \frak{a}_{k} (n)q^{n} $$F(q)k:=∏n≥1(1−qn)4k(1+q2n)2k=∑n≥0ak(n)qn be the eta quotients. The coefficients $\frak{a}_{1} (n)$a1(n) can be interpreted as a certain kind of restricted divisor sums. In this paper, we give the signs and modulo values for $\frak{a}_{1} (n)$a1(n) and $\frak{a}_{2} (m)$a2(m) and calculate several convolution sums involving $\frak{a}_{k} (n)$ak(n).

The mixed layer depth (MLD) is generally estimated using in situ or model data. However, MLD analyses have limitations due to the sparse resolution of the observed data. Therefore, this study reconstructs three-dimensional (3D) ocean thermal structures using only satellite sea surface measurements for a higher spatial and longer temporal resolution than that of Argo and diagnoses the decadal variation of global MLD variability. To simulate the ocean thermal structures, the relationship between the ocean subsurface temperature and the sea surface fields was computed based on gridded Argo data. Based on this relationship, high spatial resolution and extended periods of satellite-derived altimeter, sea surface temperature (SST), and wind stress data were used to estimate the 3D ocean thermal structures with 0.25° spatial resolution and 26 standard depth levels (5–2000 m) for 24 years (1993–2016). Then, the MLD was calculated using a temperature threshold method (∆T = 0.2 °C) and correlated reasonably well (>0.9) with other MLD datasets. The extended 24-year data enabled us to analyze the decadal variability of the MLD. The global linear trend of the 24-year MLD is −0.110 m yr−1; however, from 1998 to 2012, the linear trend is −0.003 m yr−1 which is an order of magnitude smaller than that of other periods and corresponds to a global warming hiatus period. Via comparisons between the trends of the SST anomalies and the MLD anomalies, we tracked how the MLD trend changes in response to the global warming hiatus.

We proposed and demonstrated a novel method to package liquid-core hexagonal photonic crystal fibers (PCFs) by utilizing a hollow optical fiber (HOF) not only as a liquid delivery tube but also as a light launching pedestal. Compact all-fiber packaging with single mode fiber input and output was experimentally achieved. Various configurations of liquid core PCFs were demonstrated by controlling the inner diameter of HOF and offsets. Based on numerical analyses and light launching experiments, we confirmed that this method could substantially enhance the light–liquid interaction efficiency, structurally prevent liquid evaporation within PCF, and providing a new versatile liquid core PCF device platform.

In [10] , Guerzhoy found the dual space for the space of cusp forms of even integral weight and studied that space with respect to the Hecke operators. In this paper, we extend that result for higher level cases. Especially, we find a basis for the dual space consisting of eigenforms for the Hecke operators, show how to calculate those eigenforms explicitly, and examine algebraicity of the Fourier coefficients of eigenforms.

The aim of this study was to discriminate between Korean and Chinese perilla seeds by using inorganic elemental analysis data combined with orthogonal partial least squares-discriminant analysis (OPLS-DA). Inorganic element content data were obtained from 29 Korean and 11 Chinese perilla seed samples distributed in Korea. Using energy dispersive X-ray fluorescence spectroscopy, 11 species of inorganic elements were detected in the perilla seed samples and eight of them were quantified. The Rb content was selected as the variable to best discriminate between Korean and Chinese perilla seeds using an S-plot generated from OPLS-DA. An accurate range for the Rb content was determined using inductively coupled plasma-optical emission spectroscopy. The Rb content is remarkably higher in Chinese perilla seeds (8.7–19.0 mg/kg) than in Korean perilla seeds (0.0–7.6 mg/kg), thereby suggesting that Rb analysis may be an appropriate approach to discriminate Chinese perilla seeds from Korean perilla seeds.

The multi-temporal scales of two physical characteristics (areas and occurrence time) of the Ross Sea Polynya (RSP) in Antarctica were analysed using a sea-ice concentration data set (1979–2014) derived from the Scanning Multichannel Microwave Radiometer, the Special Sensor Microwave Imager and Sensor Microwave Imager Sounder. Then, the Ensemble Empirical Mode Decomposition (EEMD) was applied to the data sets to decompose signals into finite numbers of intrinsic mode functions and a residual mode: long time trend. This approach allowed us to understand the long-term variability of the RSP area and occurrence in response to atmospheric forcing through teleconnections between low and high latitudes by comparing the Nino3.4 and Southern Annular Mode (SAM) indices. The nonlinear trend of the RSP areas derived from the EEMD residual had an upward trending shift in the early 1990s and was fairly consistent with the nonlinear trend of Nino3.4. However, the trend of RSP occurrence time progressively increased and had a significant effect on the long time scale. The trend of the RSP area is significantly correlated (+0.98) with the ratio of the trend of the meridional to zonal wind components related with the nonlinearity of Nino3.4, suggesting that meridional wind stress dominated the changes of the polynya area in the Ross Sea. In addition, the nonlinear trends between the SAM and RSP occurrence time show a strong positive correlation, contributing to the earlier onset of polynya expansion and delayed connection with the open ocean owing to enhanced southerly winds.

We report a new efficient light guidance along a liquid core using an open V-groove. Guiding properties were analyzed using finite element method in terms of the single mode guidance condition, and the corresponding modal birefringence. We experimentally demonstrated a silica V-groove fiber with an opening angle of 40°, which was spliced to single mode fibers at both ends. A liquid with the refractive index of 1.455 was filled to serve as a core along a maximum length of 47cm. We confirmed the single mode guidance and birefringence consistent to theory, which will enable polarimetric liquid sensing.

We have studied a new technique to make the periodic structure. we hypothesized the theory of cavitation and superheated liquid to explain the making principle and performed the simulation for that. As a result, it's obtained that the distribution of pressure, density and temperature of liquid in the HOF when the heat source moves. This new structure gives us the novel method with a new material as the long period fiber grating of mode converter fiber.

A prototype 5-GHz 500-kW CW klystron (model E3762 provided by Toshiba Electron Tubes & Devices Co. Ltd.) has been operating as the RF source for the lower hybrid current drive (LHCD) system in the KSTAR tokamak. A cavity design study is being carried out with a simulation code based on the main klystron’s operation parameters in order to investigate how the efficiency of the 5-GHz 500-kW CW klystron prototype can be enhanced. This is being done by simulating the klystron’s performances for various cavity parameters, including the number of cavities, the inter-cavity distance, and the cavity’s tuning frequencies. The simulation has been done with the FCI (field charge interaction) code aided by a matlab script for scanning input parameters. The initial set of scan parameters was obtained by benchmarking the E3762 klystron, and we are able to obtain optimized design parameters for a cavity system with better efficiency by adopting a multi-cell output cavity. However, the multi-cell output cavity is prone to self-oscillations due to the prolonged (several half RF periods) beam-field interaction along its multiple gaps. We have checked the feasibility of the optimization by evaluating the stability of the output cavity system. The stability is given by the ratio of a beam-loading conductance to the circuit conductance.

Long-period fiber gratings (LPFGs) are useful for environmental sensing under conditions of high corrosiveness and electromagnetic interference. Most LPFGs are fabricated by coherent or high-power UV illumination of an optical fiber under an amplitude mask, resulting in narrow and environmentally-dependent band rejection. We present a hybrid LPFG waveguide fabricated without an amplitude mask through polymer self-assembly under low-power incoherent UV illumination, which demonstrates high-temperature sensitivity in its transmission spectrum compared to LPFG sensors based purely on silica waveguides. A sensitivity of 1.5 nm °C -1 is obtained experimentally for attenuation near 1180 nm, and a sensitivity of 4.5 nm °C -1 with a low random error was obtained with a composite of attenuation bands. Finite element method simulations and coupling mode theory reveal this to be due to a thermo-optic coefficient one order of magnitude greater than that of fused silica. The device has potential for a simple and inexpensive transmission intensity based temperature sensor consisting of an infrared light source, the LPFG, a bandpass filter, and a photodiode.