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The structural and electrochemical properties of the interface formed between a Na6SOI2 solid electrolyte and a metallic Na anode were investigated by using first-principles calculations. Stable interface formation and fast ionic conductivity were found.

The complementary M-ary orthogonal spreading with orthogonal frequency division multiplexing (CMOS-OFDM) is an efficient scheme for providing high bit error rate (BER) performance and low peak to mean envelop power ratio (PMEPR) in high frequency (HF) communications system. In the CMOS-OFDM, orthogonal spreading OFDM is implemented based on orthogonal complementary sequence pairs where there is an issue that one data symbol is transmitted through two OFDM symbols. In this paper, we present the M-ary orthogonal spreading OFDM scheme using complex complementary sequences which satisfy real domain orthogonality. The complementary real orthogonal spreading OFDM (CROS-OFDM) is restrict the PMEPR to 3dB and provides two times the bit rate of CMOS-OFDM. The CROS-OFDM scheme uses zero-center complementary sequences like the CMOS-OFDM and hence it is suitable to the HF OFDM and Wi-Fi system where the direct current subcarrier is not used. The simulation results show that the CROS-OFDM provides higher bit rate and BER performance.

First-principles study of intrinsic point defects and defect complexes in layered sodium titanate Na2Ti3O7 was reported to identify the effects on electrode voltage and Na diffusion activation energy for sodium-ion batteries.

Quantum chemical parameters~(QCPs) of four additives were calculated by using DFT, and MD simulations were performed. By comparing binding energies of four additives (benzalacetone~(BA), sodium benzoate~(SB), polyoxyethylene nonylphenylether~(NP) and dispersant NNO), with Zn~(001) surface, BA has the smallest binding energy, which is due to the smallest hardness parameter, and NNO has the largest binding energy, which is due to the largest dipole moment despite its small hardness parameter. In order to enhance the adsorption of BA onto Zn~(001) surface, NP was selected to be combined with BA, because BA has the lowest energy level of LUMO, which is more capable of accepting electrons from Zn~(001) surface than others, and NP has the highest energy level of HOMO, which is more capable of donating electrons to Zn~(001) surface than others. By calculating the binding energies of the complex of BA and NP, it has larger binding energy than individual BA, SB, and NP, but smaller than NNO.

Our study was carried out to determine the control efficacy of sodium hypochlorite (NaOCl) for violet root rot caused by Helicobasidium mompa in apple. The experiment was conducted in the farm located at Chungbuk province in South Korea from 2014 to 2016. When infected apple trees were treated at least two or three times with 31.25 and 62.5 ml/l available chlorine content in NaOCl, it greatly increased the rooting of rootstock, and restored the tree crown density by 44.4-60.5%. In addition, the number of commercial fruit setting was increased by 54.3-64.5%, and the total starch content in shoots was significantly higher than other non-treated apple trees. However, the untreated disease control and thiophanate-methyl WP treated trees showed the symptom of dieback. Therefore, our results indicate that the drenching treatment of NaOCl with 31.25-62.5 ml/l available chlorine content more than two times from late fall to early spring could effectively control the violet root rot and recover tree vigor up to 60%.

In this paper, an effective method for the classification process simulation in 75¬mm hydrocyclone is considered. The simulation results and computational time are compared using Reynolds stress model (RSM) and different large eddy simulation (LES) subgrid-scale models as turbulence models, and the volume of fluid model (VOF) as a multiphase model. The Lagrangian discrete phase model (DPM) is used to simulate the classification process of particles. As the experimental result for comparison of simulation results, Hsieh's experimental data are used. When the different LES subgrid-scale models are used, the solution converges stably by various solution convergence methods without increasing the grid numbers or reducing the size of time steps than RSM model. As a result, it is confirmed that when an appropriate simulation method is applied with the LES-WMLES S-Omega model, more accurate axial water flow velocity distribution and particle classification simulation results can be obtained at a computational cost similar to that of using the RSM model.

We investigate the variation of structural, elastic, electronic, and optical properties of all-inorganic bromide and chloride perovskite solid solutions of CsPb(Br1−xClx)3 using first-principles calculations within the virtual crystal approximation.

Using self-consistent phonon calculations, we reveal that strong anharmonicity and twofold rattling modes of Cs2SnI6 induce an ultralow thermal conductivity of 0.11 W m−1 K−1 at 300 K, rarely expected of simple and single-crystalline solids.

Organic spacer cations with aromatic rings are more favourable for enhancing the moisture stability of FAPbI3 3D/2D interfaces than those with aliphatic chains. The anilinium-based system shows the highest resistance to water penetration.

Lung cancer is one of the most fatal disease with high lethality. In general lung cancers are diagnosed by radiologists. But checking radiological image is a very toilsome work for radiologists because it requires long time practice and high concentration. So, many computer-aided diagnosis (CAD) systems were introduced to cooperate with radiologists and nowadays lots of CAD systems based upon deep learning exceed human experts in diagnosing accuracy. And the remarkable thing is that the much of progress has been made in designing architectures. But, in this paper, a new pre-processing method (lung-range-standardization) is proposed in order to improve the general accuracy of lung-related diagnosis systems and to increase the utility of LIDC dataset. And the efficiency of the proposed pre-processing method is validated through comparison between the nodule segmentation model trained using lung-range-standardization and the nodule segmentation model, which is trained without lung-range-standardization.

Antimicrobial resistance is one of the most urgent global health threats. The need for the qualitative evaluation of antibiotic use at the national level is increasing. To identify areas for improvement, we aimed to assess the prevalence and appropriateness of antibiotic prescriptions during hospitalization and ambulatory care in Korea.The prevalence and appropriateness of antibiotic prescriptions on 29 August 2018 were assessed for 20 hospitals in Korea. Infectious disease specialists determined appropriateness. Except for antiviral and anti-tuberculosis agents, all antibacterial or antifungal agent prescriptions during hospitalization or ambulatory care were evaluated.The prevalence of antibiotic prescription was 14.1% (8,400/59 216 patients) on the study date. Antibiotics were prescribed for 50.8% of inpatients (6557/12 902), with two or more antibiotics prescribed for 27.4% (1798/6557) of patients. A total of 10 948 prescriptions (7999 therapeutic, 2105 surgical prophylaxes, and 844 medical prophylaxes) were included in the final analysis, and 27.7% of these were inappropriate. Surgical prophylaxis was inadequately prescribed most frequently (54.4%), followed by medical prophylaxis (29.5%) and therapeutic antibiotics (20.5%). The most common indications for therapeutic antibiotics were respiratory (29.1%, n=2332), gastrointestinal (22.4%, n=1791), and urinary tract infections (13.1%, n=1050). The most frequently prescribed antibiotics were cephalosporins (52.0%, n=5490), followed by beta lactam/beta lactamase inhibitors (13.7%, n=1373), fluoroquinolones (9.1%, n=957), and metronidazole (6.6%, n=699).This was the first nationwide qualitative antibiotic prescription adequacy evaluation in Korea. A significant proportion of antibiotic prescriptions were inappropriate. Therefore, interventions for high-frequency infections and prescription antibiotics are needed.