• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.2
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• pp.217-225
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• 2019

Objectives: The aim of this study is to evaluate the quality management systems of domestic asbestos survey and monitoring service providers and the relationships with the number of licenses or designations and sales performances. Methods: Data on quality management systems were collected by assessors who were assigned by the Korea Occupational Safety and Health Agency(KOSHA) during a pilot evaluation program for designated asbestos survey and monitoring service providers in 2016 using evaluation criteria developed by KOSHA. Basic characteristics, evaluated scores, and sales performance were gathered and statistically analyzed. Results: The median and arithmetic mean of the total scores were 0.64 and 0.66. Evaluation fields that scored highly with the highest percentages were sales performance, installation and availability of equipment, compliance with the mandatory minimum number of airborne samples, laboratory independence, and results of proficiency analytical testing, in that order. Evaluation fields that received low marks with the highest percentages were the training of personnel, blank field samples, calibration of flow rates, preliminary check and visual inspection of the work area prior to the clearance test, and review and approval of final reports, in that order. Comparison of normalized scores between service providers registered for asbestos and other tasks and those designated for only asbestos showed significant differences in their evaluated scores. Sales performance did not show a positive correlation with evaluated scores. Conclusions: The quality management systems of domestic asbestos survey and monitoring service providers were poor. High scores were recorded mostly in evaluation fields related to regulatory requirements. Low scores were recorded mostly in evaluation fields related to documentation and recordkeeping. Considering the low influence of quality on sales performance, the government needs to evaluate the quality management of asbestos survey and monitoring service providers and provide the results to public in order to address their low levels of quality management.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.4
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• pp.151-160
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• 2019

EPC companies to continue operating overseas, it is increasingly becoming apparent that risk is no longer something to be avoided but a subject to be managed. During the bidding stage, the requirements, specifications and project line items within the bid package must be studied in details to analyze the various risk factors in order to avoid cost overruns. However, reviewing vast quantities of bidding documents is time consuming and labor intensive and is not an easy task and this is where automated information technology can help. For this study, I have constructed an ITB analysis model based on Watson AI that can analyze and apply vast amount of documents more effectively in a short time. Configuration of the Watson Explorer AI architecture for AI-based ITB risk management model research, the selection of learning procedures and analysis subjects, and the performance evaluation criteria were defined, and a test bed was constructed to conduct a pilot research. Consequently, I verified the effectiveness of the analytical time reduction and the quality of its results and VOC operations by professionals.

• International journal of steel structures
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• v.18 no.4
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• pp.1191-1199
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• 2018

Concepts of submerged floating tunnels (SFTs) for land connection have been continuously suggested and developed by several researchers and institutes. To maintain their predefined positions under various dynamic environmental loading conditions, the submerged floating tunnels should be effectively moored by reasonable mooring systems. With rational mooring systems, the design of SFTs should be confirmed to satisfy the structural safety, fatigue, and operability design criteria related to tunnel motion, internal forces, structural stresses, and the fatigue life of the main structural members. This paper presents a feasibility study of a submerged floating tunnel moored by an inclined tendon system. The basic structural concept was developed based on the concept of conventional cable-stayed bridges to minimize the seabed excavation, penetration, and anchoring work by applying tower-inclined tendon systems instead of conventional tendons with individual seabed anchors. To evaluate the structural performance of the new type of SFT, a hydrodynamic analysis was performed in the time domain using the commercial nonlinear finite element code ABAQUS-AQUA. For the main dynamic environmental loading condition, an irregular wave load was examined. A JONSWAP wave spectrum was used to generate a time-series wave-induced hydrodynamic load considering the specific significant wave height and peak period for predetermined wave conditions. By performing a time-domain hydrodynamic analysis on the submerged floating structure under irregular waves, the motional characteristics, structural stresses, and fatigue damage of the floating tunnel and mooring members were analyzed to evaluate the structural safety and fatigue performance. According to the analytical study, the suggested conceptual model for SFTs shows very good hydrodynamic structural performance. It can be concluded that the concept can be considered as a reasonable structural type of SFT.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.36 no.5
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• pp.155-164
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• 2020

This research used Analytic Hierarchy Process(AHP) to analyze the importance and priority of functional space and evaluation factors of each functional space of the military dining facility. Dining in the military is an important factor in restoring combat power and promoting morale. The military dining facility serves as a not only for meals, but also for watching TV, education and club activities. Workers working in dining facility spend most of their work hours in dining facility, perform tasks such as cooking, dishwashing, and leftover disposal, and take breaks. As such, the military dining facility is a space where various functions are performed, and space planning should take into account these various functions when planning the building of the dining facility. However, the criteria for defense and military facilities, which are the basis for planning the space of military dining facility, are calculated only by simply analyzing the standard floor plan to match the size of the person-to. Therefore, when there is space to be reduced in the total area, there are side effects such as leaving visible table space without consideration for priority or functional space, unseen office space, and adjusting the entire area through reduction of the lounge. Accordingly, based on the priority of the space that the staff of the military dining facility considers important, this research aims to analyze the characteristics of each functional space through classification according to its unique function. This can be an indicator that can be used as a basis for future revision of the building floor area standards of the defense and military facilities standards, and it can improve usability with an efficient space plan that takes into account the characteristics of the Korean military and the satisfaction of its workers. Furthermore, efficient use of the defense budget through rational building plans can contribute to budget reduction.

• Korean Journal of Plant Resources
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• v.34 no.1
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• pp.52-58
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• 2021

Homogenization of quality was important in order to use herbal medicines as pharmaceuticals. To solve this problem, it was important to establish quality standards. Atractylodis Rhizoma Alba has no quantitative method in the Korean Pharmacopoeia. Thus, we have researched to improve the quality evaluation method of Atractylodis Rhizoma Alba with an HPLC. Atractylenolide III and atracylodin were selected as potential marker compounds. This analytical procedure was subject to validation. According to validation guideline of South Korea's Ministry of Food and Drugs Safety, the specificity, linearity, precision, range, quantitative limits, detection limits and accuracy were measured. Because the specificity, linearity, precision, range, quantitative limits, detection limits and accuracy meet criteria of the guideline, the analytic method was validated. With this analysis, Atractylodis Rhizoma Alba and Atractylodis Rhizoma analyzed. As a result, both atractylenolide III and atracylodin appear to be suitable standard compounds. it confirmed that tractylodes Rhizome, similar to Atractylodes Rhizome Alba, could be distinguished.

• Structural Engineering and Mechanics
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• v.77 no.4
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• pp.441-461
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• 2021

Reinforced concrete (RC) columns are crucial in building structures and they are of higher vulnerability to terrorist threat than any other structural elements. Thus it is of great interest and necessity to achieve a comprehensive understanding of the possible responses of RC columns when exposed to high intensive blast loads. The primary objective of this study is to derive analytical formulas to assess vulnerability of RC columns using an advanced numerical modelling approach. This investigation is necessary as the effect of blast loads would be minimal to the RC structure if the explosive charge is located at the safe standoff distance from the main columns in the building and therefore minimizes the chance of disastrous collapse of the RC columns. In the current research, finite element model is developed for RC columns using LS-DYNA program that includes a comprehensive discussion of the material models, element formulation, boundary condition and loading methods. Numerical model is validated to aid in the study of RC column testing against the explosion field test results. Residual capacity of RC column is selected as damage criteria. Intensive investigations using Arbitrary Lagrangian Eulerian (ALE) methodology are then implemented to evaluate the influence of scaled distance, column dimension, concrete and steel reinforcement properties and axial load index on the vulnerability of RC columns. The generated empirical formulae can be used by the designers to predict a damage degree of new column design when consider explosive loads. With an extensive knowledge on the vulnerability assessment of RC structures under blast explosion, advancement to the convention design of structural elements can be achieved to improve the column survivability, while reducing the lethality of explosive attack and in turn providing a safer environment for the public.

• Steel and Composite Structures
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• v.37 no.6
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• pp.663-678
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• 2020

This paper proposes a novel topology optimization method generating multiple materials for external linear plane crack structures based on the combination of IsoGeometric Analysis (IGA) and eXtended Finite Element Method (X-FEM). A so-called eXtended IsoGeometric Analysis (X-IGA) is derived for a mechanical description of a strong discontinuity state's continuous boundaries through the inherited special properties of X-FEM. In X-IGA, control points and patches play the same role with nodes and sub-domains in the finite element method. While being similar to X-FEM, enrichment functions are added to finite element approximation without any mesh generation. The geometry of structures based on basic functions of Non-Uniform Rational B-Splines (NURBS) provides accurate and reliable results. Moreover, the basis function to define the geometry becomes a systematic p-refinement to control the field approximation order without altering the geometry or its parameterization. The accuracy of analytical solutions of X-IGA for the crack problem, which is superior to a conventional X-FEM, guarantees the reliability of the optimal multi-material retrofitting against external cracks through using topology optimization. Topology optimization is applied to the minimal compliance design of two-dimensional plane linear cracked structures retrofitted by multiple distinct materials to prevent the propagation of the present crack pattern. The alternating active-phase algorithm with optimality criteria-based algorithms is employed to update design variables of element densities. Numerical results under different lengths, positions, and angles of given cracks verify the proposed method's efficiency and feasibility in using X-IGA compared to a conventional X-FEM.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.16 no.2
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• pp.97-105
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• 2021

Objectives This study is aimed to evaluate cost-effectiveness of treatment of Korean Medicine for whiplash associated disorders (WAD) and to suggest the direction of future research. Methods We searched papers in Pubmed database to use some keywords indicating whiplash injury syndrome, treatment of Korean Medicine and cost-effectiveness. After searching, appropriate papers were selected depending on the exclusion criteria. The selected papers were analyzed in the sections of author, publication year, intervention and control groups, outcome measurement, the list including in the cost, cost-effectiveness, cost-utility and study design. Results Four studies about effect of Korean medicine and 3 studies about economic evaluation were finally included. Acupuncture was effective for balance disorder and neck pain. Economic evaluation studies used analytical decision model or cost-consequence analysis. Cost-effectiveness analysis using visual analog scale and cost-utility analysis using quality adjusted life years were performed. Initiating timing of proper management affected the consequence of treatments. Direct and indirect medical costs including supportive devices, and non-medical costs such as litigation were considered. Conclusions We conclude that studies haven't been conducted so far to evaluate the cost-effectiveness of Korean Medicine in whiplash injury syndrome. Thus, future studies are needed in this section.

• Journal of Korean Physical Therapy Science
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• v.28 no.3
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• pp.11-29
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• 2021

Background: The purpose of this study is to investigate the effects of virtual reality on gait, balance, and upper extremity functions compared to other independent variables or no variables. Additionally, the possibility of virtual reality for stroke patients was discussed. Design: Meta-analysis. Methods: The search for this study was a search term that combined stroke, virtual reality, and training, and the electronic search was conducted through EMBASE, MEDLINE, and Cochrane Library. As a result of the search, 21 studies satisfying the selection criteria of the target study were confirmed as the final analysis target. This study consisted of 21 randomized experimental studies and 21 randomized controlled trials, and the total number of participants was 642. [Experimental group (n=314), control group (n=328); total 642]. As a result of the study, upper extremity function was assessed using a box and block test, a modified Ashworth scale, and a scale including range of motion. The balance was evaluated by the berg balance scale. Gait was a Timed Up and Go test (TUG), stride length, and gait function. Scales including a walking rate scale were evaluated. The effect size for the intervention of the analytical study was meta-analyzed with the RevMan 5.3.3 program of the Cochrane library. Results: The results of the study showed that the function of walking was statistically significant. Balance showed statistically significant results. The upper extremity function showed no statistically significant results. Conclusion: Through this rehabilitation treatment by applying virtual reality environment to the rehabilitation of stroke patients in the future can be proposed as an effective intervention method for the balance and gait function of stroke patients.

• Journal of Aerospace System Engineering
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• v.16 no.3
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• pp.1-9
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• 2022

In this study, for development of the MDO (Multi Disciplinary Optimization) framework, the flight dynamic characteristic parameters of the ChangGong-91, a light aircraft, were extracted by an analytical method based on various semi-empirical methods, and the flight test method was compared and evaluated. The semi-empirical analysis methods for comparative subjects were the Perkins method, McCormick method, and Smetana method. The major stability/control derivatives and dynamic factors were calculated, using each method. As the comparison criteria, the flight test derivative estimates and dynamic factors were processed, using the output error method. Additionally, the flight characteristics of the light aircraft were analyzed and evaluated according to the provisions of the Korean Airworthiness Standard (KAS) of the Ministry of Land, Infrastructure and Transport, and MIL-F-8785C for the U.S. military.