A study on nutrition knowledge and dietary behavior of elementary school children in Seoul

The purpose of this study was to investigate the nutrition and diet related knowledge, attitude, and behavior of elementary school children in Seoul. The subjects included were 439 (male 236, female 203) elementary school children in the 4th to the 6th grades. The statistical analysis was conducted using SPSS 12.0 program. The average obesity index (OI) was 104.98 and 99.82 for male and female subjects, respectively. The average percentage of underweight, normal, overweight and obese of subjects was 33.7%, 32.8%, 12.3%, and 19.4%, respectively. The percentage of the underweight group of female subjects was higher than that of the male subjects. The percentage of the obese group of male subjects was higher than that of the female subjects. The average score of nutrition knowledge, nutrition attitude and dietary behavior was 6.8, 7.44, and 7.34, respectively. Dietary behavior of male subjects was positively correlated with parents' education levels, monthly household income and nutrition attitude. Dietary behavior of female subjects was positively correlated with monthly household income, nutrition knowledge and nutrition attitude. Dietary behavior of female subjects was positively correlated with obesity index (OI). Proper nutrition education and intervention are required for the improvement of elementary school children's nutrition knowledge, nutrition attitudes and dietary behaviors

Efficient Performance of Electrostatic Spray-Deposited TiO2 Blocking Layers in Dye-Sensitized Solar Cells after Swift Heavy Ion Beam Irradiation

A compact TiO2 layer (~1.1 μm) prepared by electrostatic spray deposition (ESD) and swift heavy ion beam (SHI) irradiation using oxygen ions onto a fluorinated tin oxide (FTO) conducting substrate showed enhancement of photovoltaic performance in dye-sensitized solar cells (DSSCs). The short circuit current density (Jsc = 12.2 mA cm-2) of DSSCs was found to increase significantly when an ESD technique was applied for fabrication of the TiO2 blocking layer, compared to a conventional spin-coated layer (Jsc = 8.9 mA cm-2). When SHI irradiation of oxygen ions of fluence 1 × 1013 ions/cm2 was carried out on the ESD TiO2, it was found that the energy conversion efficiency improved mainly due to the increase in open circuit voltage of DSSCs. This increased energy conversion efficiency seems to be associated with improved electronic energy transfer by increasing the densification of the blocking layer and improving the adhesion between the blocking layer and the FTO substrate. The adhesion results from instantaneous local melting of the TiO2 particles. An increase in the electron transport from the blocking layer may also retard the electron recombination process due to the oxidized species present in the electrolyte. These findings from novel treatments using ESD and SHI irradiation techniques may provide a new tool to improve the photovoltaic performance of DSSCs

Clinically compatible dual fluorescence wide-field imaging for in-situ detection of gastrointestinal neoplastic lesions

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Implementation of a Noise-Shaped Signaling System through Software-Defined Radio

Along with the development of electromagnetic weapons, Electronic Warfare (EW) has been rising as the future form of war. Especially in the area of wireless communications, high security defense systems such as Low Probability of Detection (LPD), Low Probability of Interception (LPI), and Low Probability of Exploitation (LPE) communication algorithms are being studied to prevent military force loss. One LPD, LPI, and LPE communication algorithm, physical-layer security, has been discussed and studied. We propose a noise signaling system, a type of physical-layer security, which modifies conventionally modulated I/Q data into a noise-like shape. To suggest the possibility of realistic implementation, we use Software-Defined Radio (SDR). Since there are certain hardware limitations, we present the limitations, requirements, and preferences of practical implementation of the noise signaling system. The proposed system uses ring-shaped signaling, and we present a ring-shaped signaling system algorithm, SDR implementation methodology, and performance evaluations of the system using the metrics of Bit Error Rate (BER) and Probability of Modulation Identification (PMI), which we obtain by using a Convolutional Neural Network (CNN) algorithm. We conclude that the ring-shaped signaling system can perform high LPI/LPE communication functioning because an eavesdropper cannot obtain the correct modulation scheme information. However, the performance can vary with the configurations of the I/Q data-modifying factors

Analysis of Iterative Erasure Insertion and Decoding of FH/MFSK Systems without Channel State Information

We analyze the symbol measures for iterative erasure insertion and decoding of a Reed-Solomon coded SFH/MFSK system over jamming channels. In contrast to conventional erasure insertion schemes, iterative schemes do not require any preoptimized threshold or channel state information at the receiver. We confirm the performance improvement using a generalized minimum distance (GMD) decoding method with three different symbol measures. To analyze performance, we propose a new analysis framework considering the “trapped-error” probability. From analysis and the simulation results, we show that ratio-based GMD decoding has the best performance among the one-dimensional iterative erasure insertion and decoding schemes

The performance of coupled (CdS:CdSe) quantum dot-sensitized TiO₂ nanofibrous solar cells

Highly porous networks and reduced grain boundaries with one-dimensional (1-D) nanofibrous morphology offer enhanced charge transport in solar cells applications. Quantum dot (QDs) decorated TiO2 nanofibrous electrodes, unlike organic dye sensitizers, can yield multiple carrier generations due to the quantum confinement effect. This paper describes the first attempt to combine these two novel approaches, in which CdS (∼18 nm) and CdSe (∼8 nm) QDs are sensitized onto electrospun TiO2 nanofibrous (diameter ∼80–100 nm) electrodes. The photovoltaic performances of single (CdS and CdSe) and coupled (CdS/CdSe) QDs-sensitized TiO2 fibrous electrodes are demonstrated in sandwich-type solar cells using polysulfide electrolyte. The observed difficulties in charge injection and lesser spectral coverage of single QDs-sensitizers are solved by coupling (CdS:CdSe) two QDs-sensitizers, resulting in a enhanced open-circuit voltage (0.64 V) with 2.69% efficiency. These results suggest the versatility of fibrous electrodes in QDs-sensitized solar cell applications. Keywords: QDs-solar cells, TiO2 nanofibrous, CdS QDs, CdSe QDs, Quantum efficienc