• Journal of the Ergonomics Society of Korea
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• v.31 no.6
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• pp.785-791
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• 2012

Objective: The aim of this study was to investigate the correlation between 3D visual fatigue and physiological measures by canonical correlation analysis enabling to categorical correlation. Background: Few studies have been conducted to investigate the physiological mechanism underlying the visual fatigue caused by processing 3D information which may make the cognitive mechanism overloaded. However, even the previous studies lack validation in terms of the correlation between physiological variables and the visual fatigue. Method: 9 Female and 6 male subjects with a mean age of $22.53{\pm}2.55$ voluntarily participated in this experiment. All participants were asked to report how they felt about their health sate at after viewing 3D. In addition, Low & Hybrid measurement test(Event Related Potential, Steady-state Visual Evoked Potential) and for evaluating cognitive fatigue before and after viewing 3D were performed. The physiological signal were measured with subjective fatigue evaluation before and after in watching the 3D content. For this study suggesting categorical correlation, all measures were categorized into three sets such as included Visual Fatigue set(response time, subjective evaluation), Autonomic Nervous System set(PPG frequency, PPG amplitude, HF/LF ratio), Central Nervous System set(ERP amplitude P4, O1, O2, ERP latency P4, O1, O2, SSVEP S/N ratio P4, O1, O2). Then the correlation of three variables sets, canonical correlation analysis was conducted. Results: The results showed a significant correlation between visual fatigue and physiological measures. However, different variables of visual fatigue were highly correlated to respective HF/LF ratio and to ERP latency(O2). Conclusion: Response time was highly correlated to ERP latency(O2) while the subjective evaluation was to HF/LF ratio. Application: This study may provide the most significant variables for the quantitative evaluation of visual fatigue using HF/LF ratio and ERP latency based human performance and subjective fatigue.

• Physical Therapy Rehabilitation Science
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• v.5 no.1
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• pp.34-39
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• 2016

Objective: Hip abductors play a role in providing stability and movement to the lower limbs. The purpose of this study was to examine the effects of hip abductor fatigue on static balance and gait in the general population. Design: One group pre-test post-test design. Methods: Thirteen university students in their twenties volunteered for the study and had underwent a functional assessment. To induce fatigue, the subjects were instructed to raise their dominant lower extremity up against a load of 50% of 1 repetition maximum while producing hip abduction in a side-lying position. Subjects were instructed to maintain an abduction speed of 30 repetitions per minute to induce fatigue. Muscle fatigue was considered to be established when subjects were unable to perform hip abduction three consecutive times along with the metronome. A post-test of balance and gait was performed immediately in order to prevent fatigue recovery. The center of pressure (COP) distance area was measured using the Zebris FDM-S Multifunction Force measuring plate. Gait performance was analyzed using the GAITRite. Results: The COP distance was increased after fatigue was induced. There was a significant increase in the standard deviation of the medio-lateral and antero-posteror distance (p<0.05). Although there was no significant difference in gait parameters, there was a significant decrease in single support time after fatigue was induced (p<0.05). Conclusions: There was an increase in static balance instability and a significant decrease in single support time during gait due to hip abductor muscle fatigue.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.3
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• pp.90-96
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• 2004

The objective of this study was to develop a model for safe work load based on a physiological model of metabolic energy of manual material handling tasks. Fifteen male subjects voluntarily participated in this study. Lifting activities with four different weights, 0, 8, 16, 24kg, and four different working frequencies (2, 5, 8, 11 lifts/min) for a lifting range from floor to the knuckle height of 76cm were considered. Oxygen consumption rates and heart rates were measured during the performance of sixteen different lifting activities. Simplified predictive equations for estimating the oxygen consumption rate and the heart rate were developed. The oxygen consumption rate and the heart rate could be expressed as a function of task variables; frequency and the weight of the load, and a personal variable, body weight, and their interactions. The coefficients of determination ($r^2$) of the model were 0.9777 and 0.9784, respectively, for the oxygen consumption rate and the heart rate. The model of oxygen consumption rate was modified to estimate the work load for the given oxygen consumption rate. The overall absolute percent errors of the validation of this equation for work load with the original data set was 39.03%. The overall absolute percent errors were much larger than this for the two models based on the US population. The models for the oxygen consumption rate and for the work load developed in this study work better than the two models based on the US population. However, without considering the biomechanical approach, the developed model for the work load and the two US models are not recommended to estimate the work loads for low frequent lifting activities.

• Korean Journal of Optics and Photonics
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• v.15 no.6
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• pp.583-590
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• 2004

The autofocus is one of the important processes in the automated vision inspection or measurements using optical microscopes, because it influences the measuring accuracy. In this paper, we used the confocal microscope configuration based on not a pinhole but a single-mode optical fiber. A single mode fiber has the functions of source and detector by applying the reciprocal scheme. As a result, we acquired a simple system configuration and easy alignment of the optical axis. Also, we embodied a fast autofocus system by acquiring the focus error signal through a source modulation technique. The source modulation technique can effectively reduce physical disturbances compared with objective lens modulation, and it is easily applicable to general optical microscopes. The focus error signal was measured with respect to the modulation amplitude, reflectance of the specimen and inclination angle of the measuring surface. The performance of the proposed autofocus system was verified through autofocusing flat mirror surface. In addition, we confirmed that source modulation rarely degrades the depth resolution by the comparison between the FWHMs of axial response curves.

• Journal of Dairy Science and Biotechnology
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• v.35 no.2
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• pp.99-104
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• 2017

The global consumption of fructose in the form of high-fructose corn syrup (HFCS) has increased considerably over the past several decades. The current intake of HFCS exceeds that of other major caloric sweeteners such as sucrose. Fructose has potentially adverse effects on human metabolism. Therefore, the objective of this study was to analyze the monosaccharide contents of 13 sweetened milk-based beverages by using high-performance liquid chromatography (HPLC). The total monosaccharide (fructose and glucose) contents of various sweetened milk-based beverages ranged from 0.60 g/100 mL (cheese) to 26.03 g/100 mL (maple caramel snack), while milk showed only 0 g/100 mL monosaccharides. The fructose-to-glucose ratio of various popular sweetened milk-based beverages ranged from not-detected (ND) to 2.24 g/100 mL, but the content of glucose was higher than that of fructose in only three samples, namely, strawberry flavored milk, shrimp chips, and maple caramel snack. The analyzed results revealed important basic information about monosaccharides in various milk-based sweetened beverages, presenting ideas for future fructose research.

• Health Policy and Management
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• v.24 no.1
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• pp.100-106
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• 2014

Background: There is no consensus on the definition of primary care in South Korea. This study's objective was to define the concept of primary care using a Delphi method. Methods: Three expert panels were formed, consisting of 16 primary care policy researchers, 45 stakeholders, and 16 primary care physicians. Three rounds of voting, using 9-point appropriateness scales, were conducted. The first round involved rating the appropriateness of 20 previously established attributes of primary care. In the second round, panelists received a summary of the first-round results and were asked to once again vote on the 10 undetermined attributes and the provisional definition. The final round involved voting on the appropriateness of the revised definition. The Korean Language Society reviewed the revised definition. Results: Four core (first-contact care, comprehensiveness, coordination, and longitudinality) and three ancillary (personalized care, family and community context, and community base) attributes were selected. The Korean definition of primary care was accomplished with all three panel groups arriving at a 'very good' level of consensus. Conclusion: The Korean definition of primary care will provide a framework for evaluating performance of primary care in South Korea. It will also contribute to resolving confusion about the concept of primary care.

• Explosives and Blasting
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• v.24 no.1
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• pp.9-19
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• 2006

The objective of this study is to propose curve fitted equations that can facilitate calculations and improve a practical applicability when the seismic performance of buried pipelines needs to be evaluated. The curve fitted equations are derived based on the evaluation of the dynamic responses of concrete pipe with a boundary condition of fixed-free ends. To study the dynamic response of underground pipe, the numerical analysis program developed in the previous research has been used. The location of maximum strain has been determined through dynamic analyses for a boundary condition of fixed-free ends. Then $wavelength{\lambda}$ of 5-1000(m) and propagation velocity(Vs) of 100-2000(m/s) have been applied at the location of maximum strain and the unit srain curve with the changes of the $wavelength{\lambda}$ and propagation velocity(Vs) has been obtaind. Non-linear least-square regression has been used to develop highly applicable curve fitted equations and various types of exponential regression equations have been checked out. Thus curve fitted equations and necessary coefficients with best results are suggested.

• The Journal of Internal Korean Medicine
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• v.40 no.6
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• pp.1169-1178
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• 2019

Objective: The purpose of this study was to investigate the effect of combined therapy with Banhasasim-tang and conventional treatment for atrophic Gastritis. Methods: The study collected data of clinical studies of combined therapy with Banhasasim-tang and conventional treatment for atrophic gastritis. Electronic databases were used, including PubMed, Cochrane, CNKI, Wanfang, CINII, J-stage, NDSL, and OASIS. The main search terms included such as "Atrophic Gastritis", "Banhasasim-tang", "BanXia Xiexin Tang". This study only included randomized controlled trials (RCTs) that adopted combined therapy with Banhasasim-tang and conventional treatment for atrophic gastritis. Results: A total of 18 RCTs were selected. They all adopted combined therapy with Banhasasim-tang and conventional treatment for atrophic gastritis. In all the studies, the intervention group significantly improved the score of effective rate, and in the 8 studies, Hp negative conversion rate was significantly improved when Banhasasim-tang was taken. Conclusion: Through the analysis of 18 RCTs, we found Banhasasim-tang combined with conventional therapy were more effective in the positive performance of atrophic gastritis than conventional therapy single contribution. However, due to the low quality of the selected studies and the lack of endoscopy, biopsy, follow-up observation, so there is a slight insufficient to prove its conclusion. Therefore, we hope that more systematic and diverse clinical studies will be conducted.

• Journal of Korean Society on Water Environment
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• v.30 no.3
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• pp.269-282
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• 2014

The objective of this study is to find out whether the developed semi-empirical biofilm model can be applicable to real BAF pilot-scale wastewater treatment. In addition, the optimum operating conditions of BAF as a function of process variables such as organic loading change can be drawn based on the simulation results of model. The results will provide the economic and efficient BAF process design and operating control. As a result, developed semi-empirical biofilm model which is relatively simple compared to mathematical model can simulate three BAF processes consisted of 25 layers within 1 seconds. When this model was used for simulating real pilot scale BAF process and the simulated water quality values were compared to experimental ones, simulated TCOD, SCOD, TN, $NH_4{^+}$-N, $NO_x{^-}$-N, alkalinity values were different to experimental ones within 21%, 20%, 8.1%, 48%, 10%, and 23%, respectively. Therefore, if the BAF system was equipped with automatic control, the BAF process can be better efficiently adapted under the condition of significant change of influent loading.

• Communications for Statistical Applications and Methods
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• v.18 no.1
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• pp.57-69
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• 2011

Researchers are continuously trying to find innovative diagnostic tests and published articles are accumulating at an enormous rate in many medical fields. Meta-analysis enables previously published study results to be reviewed and summarized; therefore, an objective assessment of diagnostic tests can be done with a meta-analysis of sensitivities and specificities. Data obtained by applying two diagnostic tests to a well-defined group of diseased patients produce a pair of sensitivity and by applying the same medical tests to a group of non-diseased subjects produce a pair of specificity. The statistical tests in the meta-analysis need to consider the correlatedness of the results from two diagnostic tests applied to the same diseased and non-diseased subjects. The associations between two diagnostic test results are often found to be unequal for the diseased and non-diseased subjects. In this paper, multivariate meta-analytic methods are studied by taking into account the different associations between correlated variables. On the basis of Monte Carlo simulations, we evaluate the performance of the multivariate meta-analysis methods proposed in this paper.