• 한국전문물리치료학회지
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• 제29권2호
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• pp.87-93
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• 2022

To solve the pathological problems of the musculoskeletal system based on evidence, a sophisticated analysis of human motion is required. Traditional optical motion capture systems with high validity and reliability have been utilized in clinical practice for a long time. However, expensive equipment and professional technicians are required to construct optical motion capture systems, hence they are used at a limited capacity in clinical settings despite their advantages. The development of information technology has overcome the existing limit and paved the way for constructing a motion capture system that can be operated at a low cost. Recently, with the development of computer vision-based technology and optical markerless tracking technology, webcam-based 3D human motion analysis has become possible, in which the intuitive interface increases the user-friendliness to non-specialists. In addition, unlike conventional optical motion capture, with this approach, it is possible to analyze motions of multiple people at simultaneously. In a non-optical motion capture system, an inertial measurement unit is typically used, which is not significantly different from a conventional optical motion capture system in terms of its validity and reliability. With the development of markerless technology and advent of non-optical motion capture systems, it is a great advantage that human motion analysis is no longer limited to laboratories.

• 대한지역사회영양학회지
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• 제16권6호
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• pp.771-781
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• 2011

The objective of this study was to assess the reliability and validity of food security measures, which was developed based on the US household food security survey module (US HFSSM) with content validity in the Korean population. The reliability and validity were assessed by internal consistency, construct validity and criterion-related validity. The study included 446 households. Among those, 46.2% were households with children. The proportion of food insecure households was 33.3%. Among those, 35.4% and 64.6% households were food insecure with hunger and without hunger, respectively. The Cronbach's alpha coefficients were 0.84 and the infit value by the Rasch model analysis ranged from 0.68 to 1.43. The scale item response curves by food insecurity severity explained well the nature and characteristics of food security, indicating the highest proportion of "yes" for the items on diet quality, followed by those with diet quantity. The result of criterion-related validity showed that food insecurity status was significantly related in a dose-response manner with the household income level, food expenditure, subjective health state, subjects' educational level. Household food security status was also related to dietary diversity regarding protein foods, fruits and fruit juice, and milk and dairy product. These findings suggest that the food security instrument is reliable and valid and would be used to assess food security status in the Korean population.

• 한국산학기술학회논문지
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• 제20권8호
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• pp.156-163
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• 2019

본 논문은 탄약의 시험 평가를 위한 탄약 운반 시스템의 개발에 관한 연구이다. 국내 탄약 시험장에서 탄약 시험 평가를 수행할 때 탄약 장전 등의 대부분 시험 평가 과정이 시험원에 의해 수행되고 있다. 즉, 탄약의 성능을 평가하기 위해 수십 kg 무게가 나가는 탄약의 이송 및 장전, 사격의 과정이 시험원에 의해 반복적으로 이뤄진다. 이 과정에서 탄약 장전 작업의 경우 인력에 의한 작업은 시험 결과의 신뢰성 저하, 시험원의 근골격계 손상, 안전사고와 같은 문제들이 발생할 소지가 있다. 이러한 문제점들을 해소하기 위해 시험용 탄약의 안전한 이송, 자동 장전 등의 운용성 향상을 위한 탄약 운반 시스템을 개발하였다. 이 논문은 운반 시스템의 설계, 제조, 그리고 운영의 효용성 등을 다루고 있다. 또한 사람에 의한 운용과 비교하여 개발된 시스템의 효용성 평가를 수행하였다. 본 연구 결과는 국내 탄약 시험장에서 안전한 시험 평가를 위해 활용될 수 있을 것이다.

• Archives of Plastic Surgery
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• 제48권3호
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• pp.269-277
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• 2021

Background The Sunnybrook facial grading scale is a comprehensive scale for the evaluation of facial paralysis patients. Its results greatly depend on subjective input. This study aimed to develop and validate an automated Sunnybrook facial grading scale (SBface) to more objectively assess disfigurement due to facial paralysis. Methods An application compatible with iOS version 11.0 and up was developed. The software automatically detected facial features in standardized photographs and generated scores following the Sunnybrook facial grading scale. Photographic data from 30 unilateral facial paralysis patients were randomly sampled for validation. Intrarater reliability was tested by conducting two identical tests at a 2-week interval. Interrater reliability was tested between the software and three facial nerve clinicians. Results A beta version of the SBface application was tested. Intrarater reliability showed excellent congruence between the two tests. Moderate to strong positive correlations were found between the software and an otolaryngologist, including the total scores of the three individual software domains and composite scores. However, 74.4% (29/39) of the subdomain items showed low to zero correlation with the human raters (κ<0.2). The correlations between the human raters showed good congruence for most of the total and composite scores, with 10.3% (4/39) of the subdomain items failing to correspond (κ<0.2). Conclusions The SBface application is efficient and accurate for evaluating the degree of facial paralysis based on the Sunnybrook facial grading scale. However, correlations of the software-derived results with those of human raters are limited by the software algorithm and the raters' inconsistency.

• 한국안전학회지
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• 제16권4호
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• pp.168-174
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• 2001

For human error analysis, the structure and situation of a task should be analyzed in advance. The paper introduces Structured Information Analysis (SIA) as a task analysis method for error analysis, and delineates the result of application on the emergency procedure of Korean Standard Nuclear Plants (KSNPs). From the task analysis about emergency procedure of KSNP, total 72 specific task goals were identified in the level of system function, and 86 generic tasks were classified from the viewpoint of physical sameness of the task description. Human errors are dependent on task types so that the result of task analysis would be used as a basis for the error analysis on the emergency tasks in nuclear power plants.

• 한국기계가공학회지
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• 제16권3호
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• pp.146-152
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• 2017

Stabilizing the operation of dual fuel diesel engines is very important. The shipbuilding industry is rapidly growing, but gear components requiring reliability are still imported from other countries. The reasoning for this is three-fold. Firstly, it is compulsory that all ships must use devices that meet the performance standards specified in the Safety of Life at Sea (SOLAS) and the convention of MARine POLlution (MAPOL) to prevent pollution caused by ships. Secondly, most ships must comply with the ship classifications specified by ship owners. Therefore, it is specified that key engine gear components must be inspected and authorized for the quality and performance specified by the Ship Register Authority. Thirdly, it is essential that devices (engine gear) for human safety in ships comply with quality standards specified in the regulations and rules by the government. The Ship Register Authority's strict quality standards and approval requirements contribute to the reduction of motivation towards new investment and technology development by device component manufacturers. Therefore, this study aims to develop a method for using infrared thermography to examine gear reliability in order to ensure gear component reliability and national competitiveness in the global market.

• 한국산학기술학회논문지
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• 제8권4호
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• pp.758-767
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• 2007

오늘날 의료기기는 내장된 소프트웨어에 의해 제어되는 전자 의료기기의 형태로 급격하게 발전하고 있다. 따라서 전자 의료기기의 품질은 내장된 의료용 소프트웨어의 품질에 의해 크게 좌우될 수밖에 없다. 특히, 의료기기가 인간의 생명과 밀접하게 연관되어 있다는 점을 고려할 때, 프로그램 가능한 전자 의료기기의 품질 측면에서도 신뢰성 측면을 특히 고려한 평가 방법이 연구되어야 할 것으로 생각된다. 본 논문에서는 소프트웨어 제품평가에 관련된 국제표준인 ISO/IEC 9126과 ISO/IEC 12119를 기반으로 하여 국내의 프로그램 가능한 전자 의료기기의 특성을 고려하여 신뢰성에 대한 평가를 위한 방법을 구축하고 아울러 신뢰성 평가 방법인 FMEA 기법을 적용할 수 있는 체계를 구축하였다.

• 한국컴퓨터정보학회논문지
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• 제27권12호
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• pp.151-159
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• 2022

본 논문은 함정 전투체계에서 신뢰성 시험 효율화를 위한 표준 아키텍처 및 무장-센서 시뮬레이터의 설계 방법을 제안한다. 제안된 표준화 아키텍처는 함정 전투체계 소프트웨어의 수정 공수 및 신뢰성 시험 수행 시간 단축을 위한 방법으로 함정 전투체계 소프트웨어에서 타 모듈의 의존도가 높은 응용을 선별하여 FORM 기법을 적용하였다. 이를 기반으로 공통요소와 가변요소를 추출, 추상화하였으며, 디자인 패턴 및 S.O.L.I.D 원칙을 고려한 아키텍처 디자인을 설계하였다. 제안된 무장-센서 시뮬레이터는 타 모듈의 의존성이 높은 요소를 식별하여 필수 기능을 구현하였고 통신 미들웨어에 기반 하여 장비의 정보를 가공 없이 직접 수신 받을 수 있도록 처리하였다. 그 결과 실제 함정 탑재장비를 대체하는 효과를 가진다. 또한 신뢰성 시험 수행 효율을 높이고 수정 사항 발생 시 수정시간을 단축할 수 있다.

• 대한안전경영과학회지
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• 제25권1호
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• pp.15-21
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• 2023

In modern society, the delivery service market has grown explosively due to rapid changes in social structure and the recent COVID-19 pandemic. Therefore, various problems such as injury to workers and an increase in human accidents are occurring due to the loading and unloading of parcels. In order to solve this problem, domestic company n is developing a "robot-based cargo loading and unloading system". In developing a new technology system, quantitative reliability targets should be set for efficient operation and development. In this paper, reliability analysis was conducted through field data for the pneumatic gripper of the "robot-based cargo loading system". The reliability of the failure data was analyzed to estimate the distribution parameters and MTTF. Random data was derived for the probability of occurrence of a failure with the estimated value. By repeating the simulation to predict the number and year of failures according to the estimated parameters of the probability distribution, it was proposed as a method that reflects realistic probabilities rather than calculating with simple arithmetic using the average MTTF previously used in the field.

• 대한인간공학회지
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• 제34권6호
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• pp.583-595
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• 2015

Objective: The purpose of this study was to determine the reliability of lower limb joint angles computed with the software ImageJ during jumping movements. Background: Kinematics is the study of bodies in motion without regard to the forces or torques that may produce the motion. The most common method for collecting motion data uses an imaging and motion-caption system to record the 2D or 3D coordinates of markers attached to a moving object, followed by manual or automatic digitizing software. Above all, passive optical motion capture systems (e.g. Vicon system) have been regarded as the gold standards for collecting motion data. On the other hand, ImageJ is used widely for an image analysis as free software, and can collect the 2D coordinates of markers. Although much research has been carried out into the utilizations of the ImageJ software, little is known about their reliability. Method: Seven healthy female students participated as the subject in this study. Seventeen reflective markers were attached on the right and left lower limbs to measure two and three-dimensional joint angular motions. Jump performance was recorded by ten-vicon camera systems (250Hz) and one digital video camera (240Hz). The joint angles of the ankle and knee joints were calculated using 2D (ImageJ) and 3D (Vicon-MX) motion data, respectively. Results: Pearson's correlation coefficients between the two methods were calculated, and significance tests were conducted (${\alpha}=1%$). Correlation coefficients between the two were over 0.98. In Vicon-MX and ImageJ, there is no systematic error by examination of the validity using the Bland-Altman method, and all data are in the 95% limits of agreement. Conclusion: In this study, correlation coefficients are generally high, and the regression line is near the identical line. Therefore, it is considered that motion analysis using ImageJ is a useful tool for evaluation of human movements in various research areas. Application: This result can be utilized as a practical tool to analyze human performance in various fields.