• Restorative Dentistry and Endodontics
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• v.40 no.1
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• pp.23-29
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• 2015

Objectives: The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. Materials and Methods: Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE), the specific self-etching adhesive system (Adhesive System P90, 3M ESPE) was used with and without pre-etching (Pre-etching/Silorane and Silorane groups). Teeth restored with methacrylate based-composite (Filtek Z250, 3M ESPE) were hybridized with the two-step self-etching system (Clearfil SE Bond, Kuraray), with and without pre-etching (Pre-etching/Methacrylate and Methacrylate groups), or three-step adhesive system (Adper Scotchbond Multi-Purpose, 3M ESPE) (Three-step/Methacrylate group) (n = 6). The restored teeth were sectioned into stick-shaped test specimens ($1.0{\times}1.0mm$), and coupled to a universal test machine (0.5 mm/min) to perform microtensile testing. Results: Pre-etching/Methacrylate group presented the highest bond strength values, with significant difference from Silorane and Three-step/Methacrylate groups (p < 0.05). However, it was not significantly different from Pre-etching/Silorane and Methacrylate groups. Conclusions: Pre-etching increased bond strength of silorane-based composite specific adhesive system to dentin.

• Journal of health informatics and statistics
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• v.43 no.4
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• pp.255-266
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• 2018

Objectives: This study compared the risk of preterm birth and low birth weight between native-born and foreign-born women. Methods: By Using the birth registration data, every woman who gave birth between 2010 and 2016 in Korea was included in the analysis. Duration from marriage to pregnancy was measured by month and multiple socioeconomic and demographic characteristics were controlled. Preterm birth (<37 weeks) and low birth weight (<2.5 kg) were used for outcome variables. Descriptive statistics and logistic regression were used for data analysis with Stata. Results: The risks of preterm birth and low birth weight for native-born and foreign-born women differed according to the duration of marriage or birth order. For the first infant, foreign-born women were more likely to have pereterm birth or low birth weight than the native-born in the early stage of marriage but nativeborn women had higher risks than the foreign-born in the middle and later stage of marriage. For the second infant, foreign-born women were less likely to have pereterm birth or low birth weight than the native-born regardless of the duration of marriage. Conclusions: The results of this study demonstrates that the risk of preterm birth and low birth weight for foreign-born women is concentrated on the early stage of marriage. Institutional and cultural supports should be given to foreign-born women to help their early settlement in the Korean society.

• Korean Journal of Remote Sensing
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• v.20 no.3
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• pp.175-188
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• 2004

The objectives of this study were to estimate leaf area index (LAI) as a function of image-derived vegetation indices, and to compare measured and estimated LAI to the results of crop model simulation. Soil moisture, crop phenology, and LAI data were obtained several times during the 2001 growing season at monitoring sites established in two central Missouri experimental fields, one planted to com (Zea mays L.) and the other planted to soybean (Glycine max L.). Hyper- and multi-spectral images at varying spatial. and spectral resolutions were acquired from both airborne and satellite platforms, and data were extracted to calculate standard vegetative indices (normalized difference vegetative index, NDVI; ratio vegetative index, RVI; and soil-adjusted vegetative index, SAVI). When comparing these three indices, regressions for measured LAI were of similar quality $(r^2$ =0.59 to 0.61 for com; $r^2$ =0.66 to 0.68 for soybean) in this single-year dataset. CERES(Crop Environment Resource Synthesis)-Maize and CROPGRO-Soybean models were calibrated to measured soil moisture and yield data and used to simulate LAI over the growing season. The CERES-Maize model over-predicted LAI at all corn monitoring sites. Simulated LAI from CROPGRO-Soybean was similar to observed and image-estimated LA! for most soybean monitoring sites. These results suggest crop growth model predictions might be improved by incorporating image-estimated LAI. Greater improvements might be expected with com than with soybean.

• Journal of Korea Port Economic Association
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• v.23 no.2
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• pp.121-144
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• 2007

In general, the design of container yard and container handling system on container terminal are focused on operation of shipside than service about chassis from outside(C/O). It is not efficient for chassis from outside. The purpose of this paper is functional assessment of efficient container terminal and for higher performance of container terminal. first, the items which are concerned with container handling at the planning of container terminal are investigated and extracted through the practical data analysis of container terminal. Also, verified problems of planning and present condition through the functional assessment. Secondly, the improvements for container throughput in container yard are proposed and examined the effectiveness of improvements about queuing time of chassis from outside and service time of transfer crane by the evaluation decision model based upon multi criteria objectives.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.330-339
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• 2008

Ground-based interceptors(GBI) comprise a major element of the strategic defense against hostile targets like Intercontinental Ballistic Missiles(ICBM) and reentry vehicles(RV) dispersed from them. An optimum design of the subsystems is required to increase the performance and reliability of these GBI. Propulsion subsystem design and optimization is the motivation for this effort. This paper describes an effort in which an entire GBI missile system, including a multi-stage solid rocket booster, is considered simultaneously in a Genetic Algorithm(GA) performance optimization process. Single goal, constrained optimization is performed. For specified payload and miss distance, time of flight, the most important component in the optimization process is the booster, for its takeoff weight, time of flight, or a combination of the two. The GBI is assumed to be a multistage missile that uses target location data provided by two ground based RF radar sensors and two low earth orbit(LEO) IR sensors. 3Dimensional model is developed for a multistage target with a boost phase acceleration profile that depends on total mass, propellant mass and the specific impulse in the gravity field. The monostatic radar cross section (RCS) data of a three stage ICBM is used. For preliminary design, GBI is assumed to have a fixed initial position from the target launch point and zero launch delay. GBI carries the Kill Vehicle(KV) to an optimal position in space to allow it to complete the intercept. The objective is to design and optimize the propulsion system for the GBI that will fulfill mission requirements and objectives. The KV weight and volume requirements are specified in the problem definition before the optimization is computed. We have considered only continuous design variables, while considering discrete variables as input. Though the number of stages should also be one of the design variables, however, in this paper it is fixed as three. The elite solution from GA is passed on to(Sequential Quadratic Programming) SQP as near optimal guess. The SQP then performs local convergence to identify the minimum mass of the GBI. The performance of the three staged GBI is validated using a ballistic missile intercept scenario modeled in Matlab/SIMULINK.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.16 no.1
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• pp.94-99
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• 2003

Objectives : Gram-positive bacteria have became increasing resistant to antibacterial agents, and hence multi-drug-resistant bacterial pathogens are now a major problem in clinical medicine. There is, therefore, a need for new antibacterial agents. In the course of our screening program for potent antibacterial agent from medicinal plants, the extract of Salvia miltiorrhiza (S. miltiorrhiza) showed antibacterial activity against methcillin resistant Staphylococcus aureus (MRSA) and antibiotic-resistant S. aureus. Methods : S. miltiorrhiza was extracted with 80$\%$ EtOH. The extract was suspended in H2O and fractionated successively with hexane chloroform, ethyl acetate, and n-buthanol. The chloroform fraction, which showed the highest antibacterial activity(MICs, 78㎍/ml) against MRSA, was chromatographed on a silica gel column and recycling prep-LC to give the pure antibacterial component. Results and Conclusions : The second fraction among the chloroform soluble portion of an aqueous EtOH extract of S. miltiorrhiza root showed outstanding antibacterial activity against MRSA and antibiotic-resistant S. aureus compared to the other fraction. An active compound was isolated from the second fraction using silica gel column chromatoraphy and recycling prep-LC. Based on these data together with the IH-, 13C-NMR, mass and mp, the active compounds were identified tanshinone Ⅰ, dehydrotanshinone Ⅰ and cryptotanshinone. Among tanshinones, cryptotanshinone and dihydrotanshinone Ⅰ MICs against MRSA and antibiotics-resistant S. aureus were 12.5, 12.5 and 6.3㎍/ml, respectively.

• The Journal of Korean Society for School & Community Health Education
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• v.18 no.2
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• pp.1-25
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• 2017

Objectives: There is higher rates of experience of suicide ideation and suicide attempt of adolescents in the Lima and Callao region compared with the results of the epidemiological study (2013) conducted by Peru National Institute of Mental Health and the Global School-based Student Health Survey (2010) which is was conducted among adolescents across all regions of Peru. Based on the PRECEDE model, this study analyzed the prevalence and the factor associated with the suicide attempt among the adolescent in a poor urban area in Peru. Methods: A stratified random sampling was used for the survey to select study participants from the 6 secondary schools based in Comas or Callao. The survey was conducted November 25th and December 4th in 2015 and a total of 738 individuals included in the analysis. In order to analyze factors influencing suicide attempt, comparison of predisposing factor, reinforcing factor, enabling factor, behavioral factor, environmental factor, psychological factors by suicide attempt and suicide risk group were identified through the chi-square test and hierarchical logistic regression. Results: Results showed that those who reported having less parental understanding, less time spent with parents, and 'almost none/none' for parental affection had more experience of suicide attempt and were more likely to sort into the high suicide risk group. Also, a greater proportion of those with the experience of suicide attempt had more experience of smoking and alcohol consumption, and experience of physical abuse and feeling insulted and depression in comparison to that of those without experience of suicide attempt. Variables that had a significant effect on suicide attempt included depression, subjective happiness, smoking experience, sexual intercourse, involvement in fight, parental affection, and gender (male). Conclusions: The results of the current study can serve as grounds for the necessity of acknowledging that adolescent suicide does not simply depend on a couple of factors, but arises from situations in which individual, home, school, social factors influence one another, and therefore adolescent suicide should be prevented and addressed through a multi-dimensional and integrated approach.

• Journal of Environmental Health Sciences
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• v.47 no.5
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• pp.454-461
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• 2021

Background: Fish and fishery products (FFPs) unintentionally contaminated with various environmental pollutants are major exposure pathways for humans. To protect human health from the consumption of contaminated FFPs, it is essential to develop a systematic tool for evaluating exposure and risks. Objectives: To regularly, accurately, and quickly evaluate adverse health outcomes due to FFPs contamination, we developed an automated dietary exposure and risk assessment system called HERA (the Human Exposure and Risk Assessment system for chemicals in FFPs). The aim of this study was to develop an overall architecture design and demonstrate the major features of the HERA system. Methods: For the HERA system, the architecture framework consisted of multi-layer stacks from infrastructure to fish exposure and risk assessment layers. To compile different contamination levels and types of seafood consumption datasets, the data models were designed for the classification codes of FFP items, contaminants, and health-based guidance values (HBGVs). A systematic data pipeline for summarizing exposure factors was constructed through down-scaling and preprocessing the 24-hour dietary recalls raw dataset from the Korea National Health and Nutrition Examination Survey (KNAHES). Results: According to the designed data models for the classification codes, we standardized 167 seafood items and 2,741 contaminants. Subsequently, we implemented two major functional workflows: 1) preparation and 2) main process. The HERA system was developed to enable risk assessors to accumulate the concentration databases sustainably and estimate exposure levels for several populations linked to seafood consumption data in KNAHES in a user-friendly manner and in a local PC environment. Conclusions: The HERA system will support policy-makers in making risk management decisions based on a nation-wide risk assessment for FFPs.

• Journal of Pharmacopuncture
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• v.24 no.3
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• pp.122-137
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• 2021

Objectives: In South Korea, traffic accident victims can be treated under automobile insurance coverage. Korean medicine (KM) clinics have reported the largest number of automobile insurance fee claims among medical institutions. This study investigated the status of the KM automobile insurance system in a single KM clinic. Methods: We retrospectively surveyed the medical charts of 342 traffic accident patients treated at the Jisung KM clinic between January 2009 and June 2017. Results: Most of the patients were men and in their 30s. The most common method of locating the clinic was an internet search. The most common traffic accident type was collision between vehicles (83.63%), with 70.76% of patients visiting during the most acute phase. The major disease codes included S434, M4836, F072, S0600, and S3350. The most frequent treatment period was within 1 month of the accident, and most patients received 10 or fewer treatments. The mean treatment duration and number of treatments were 37.68 ± 45.11 days and 11.68 ± 10.63 treatments, respectively. The initial pain numerical rating scale (NRS), 7.32 ± 0.96, decreased to 3.57 ± 1.40 at the end of treatment, with a symptom improvement score of 1.87 ± 0.60. Regarding sex, age, disease duration, location at the time of the accident, presence of additional and psychological symptoms, and chuna, there were statistically significant differences in treatment duration and number of treatments. A higher number of treatments and the longer treatment duration was associated with a higher initial NRS, lower post-treatment NRS, and better improvement score. Since the introduction of traffic accident (TA) pharmacopuncture, the rate of use of a single type of pharmacopuncture increased; however, no significant differences in treatment duration and number, NRS before and after treatment, and improvement score were observed between treatment groups before and after TA pharmacopuncture. No adverse reactions were observed for any treatment. Conclusion: This study confirmed the previous findings of a high treatment effect of KM under automobile insurance. We also observed significant correlations based on a detailed medical status, which may explain the increasing use of KM in the automobile insurance system. Additional multi-center studies in different regions are needed.

• Nutrition Research and Practice
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• v.15 no.6
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• pp.761-772
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• 2021

BACKGROUD/OBJECTIVES: Understanding the factors associated with fish consumption is necessary to determine strategies to improve the fish consumption particularly those high in omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA). The aim of this study was to analyse the correlation between a mother's perspective on fish and actual fish consumption in their children. SUBJECTS/METHODS: Two hundred thirty-one elementary school children grade 3-6 and their mothers in Surakarta were recruited using multi stage random sampling for this study. Data was collected in July and August 2017. A validated questionnaire consisted of 3 topics including knowledge related to the health benefits and organoleptic properties of fish and cooking technique-related attitudes on fish were used to measure the mother's response to the fish properties. A validated food frequency questionnaire and a food picture book of fish specifically designed for the survey were developed and used to assess fish consumption of the children. A χ² test was used to analyse the correlation between the mothers' perspective on fish and their children's fish consumption. RESULTS: The median fish consumption in children was 65 g/d with fried non-oily or lean fish, e.g., milkfish (locally called Bandeng) and catfish (locally called Lele) were consumed more than oily fish as well as processed fish products. Of all children, 31% met the fish consumption recommended by the Environmental Protection Agency-Food and Drug Administration 2017. There was no relationship between a mother's knowledge related to health benefits, organoleptic properties and cooking technique-related attitude toward fish and her child's fish consumption. CONCLUSIONS: The fish consumption of children is not influenced by their mother's perspective on fish. Nutrition education strategies are warranted to improve fish consumption and maintain the optimal benefits by consuming fish, including fish high in n-3 LCPUFA.