• 한국의류학회지
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• 제41권1호
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• pp.184-195
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• 2017

Baseball is a life sport that gives vitality to people. However, currently available leg guards do not have a variety of sizes and it is very difficult to purchase a leg guard that is suitable for the size of a specific consumer. Therefore, this study investigated the size system of a leg guard sold in the market and suggested a grading deviation suitable for the legs of Korean males. The results of the study were as follows. First, most brands were sold only in three size systems as children's, teenagers, and adults. Adult size systems were not subdivided. Second, Korean male legs were classified into Group 1 (large girth and height and lower body muscle) and Group 2 (small girth and height and low underbody muscle). Third, the size system is based on vertical items such as height and mid-thigh circumference. Each group produced 10 sizes. The smallest height or the largest height was also found to be about 4.5 to 5.0cm smaller or larger than the sample size for each group. The total length of the leg guard was about 2.5cm when the height was increased or decreased by one size. It was confirmed that the deviation of the circumference of the mid-thigh should be about 2.0cm larger or smaller than the sample size even if the height is the same. The deviation of the knee circumference and ankle circumference was smaller than the other circumference. In conclusion, the dimension combinations of the leg guard must be set differently to provide a leg guard with high size suitability according to leg type.

• 패션비즈니스
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• 제20권3호
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• pp.17-29
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• 2016

To develop baseball catcher leg guards, 3-dimensional (3D) methodologies, which are 3D human body data, reverse engineering, modeling, and printing, optimized guard design for representative positions. Optimization was based on analysis of 3D body surface data and subjective evaluation using 3D printing products. Reverse engineering was used for analysis and modeling based on data in three postures: standing, $90^{\circ}$ knee flexion, and $120^{\circ}$ knee flexion. During knee flexion, vertical skin length increased, with the thigh and knee larger in anterior area compared to the horizontal dimension. Moreover, $120^{\circ}$ knee flexion posture had a high radius of curvature in knee movement. Therefore, guard designs were based on increasing rates of skin deformation and numerical values of radius of curvature. Guards were designed with 3-part zoning at the thigh, knee, and shin. Guards 1 and 2 had thigh and knee boundaries allowing vertical skin length deformation because the shape of thigh and knee significantly affects to its performance. Guard 2 was designed with a narrower thigh and wider knee area than guard 1. The guards were manufactured as full-scale products on a 3D printer. Both guards fit better in sitting than standing position, and guard 2 received better evaluations than guard 1. Additional modifications were made and an optimized version (guard 3) was tested. Guard 3 showed the best fit. A design approach based on 3D data effectively determines best fitting leg guards, and 3D printing technology can customize guard design through immediate feedback from a customer.

• 한국생활과학회지
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• 제24권4호
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• pp.555-569
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• 2015

During a design process of a protective equipment for sports activities, minimizing movement restrictions is important for enhancing its functions particularly for protection. This study presents a three-dimensional(3D) modeling methodology for designing baseball catcher's leg guards that will allow maximum possible performance, while providing necessary protection. 3D scanning is performed on three positions frequently used by a catcher during the course of a game by putting markings on the subject's legs at 3cm intervals : a standing, a half squat with knees bent to 90 degrees and 120 degrees of knee flexion. Using data obtained from the 3D scan, we analyzed the changes in skin length, radii of curvatures, and cross-sectional shapes, depending on the degree of knee flexion. The results of the analysis were used to decide an on the ideal segmentation of the leg guards by modeling posture. Knee flexions to 90 degrees and to $120^{\circ}$ induced lengthwise extensions than a standing. In particular, the vertical length from the center of the leg increases to a substantially higher degree when compared to those increased from the inner and the outer side of the leg. The degree of extension is varied by positions. Therefore, the leg guards are segmented at points where the rate of increase changed. It resulted in a three-part segmentation of the leg guards at the thigh, the knee, and the shin. Since the 120 degree knee-flexion posture can accommodate other positions as well, the related 3D data are used for modeling Leg Guard (A) with the loft method. At the same time, Leg Guard (B) was modeled with two-part segmentation without separating the knee and the shin as in existing products. A biomechanical analysis of the new design is performed by simulating a 3D dynamic analysis. The analysis revealed that the three-part type (A) leg guards required less energy from the human body than the two-part type (B).

• 한국의류학회지
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• 제39권1호
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• pp.63-76
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• 2015

This study conducted a survey to gauge the buying and wearing propensities of wearers of leg guards made for baseball catchers, as well as product characteristics of preferred leg guards. Data from the survey were analyzed to obtain basic data for the development of an advanced leg guard design. Degree of compression, horizontal distance, cross section view and outline 3D sketch were also analyzed from the 3D data of leg guards; in addition, mobility and kinematic analysis were conducted through a wearing test. The survey indicated that imported products dominate the current retail market because they are appreciated by customers in terms of fit, price, brand, and protection. Representative complaints of products were discomfort, pressure, and the heavy-weight of the leg guards in general attributed to overall structure and 3D shape. When the pressure was lower on the front area of knee, it feels better to wear and the average knee angular velocity during the up and down motion increased, which suggests a better design from a kinematic point of view. The knee is the primary part of the body responsible for any movement of the lower limbs; consequently, the degree of compression and support stability of the leg guards near the knee area are important factors to evaluate the performance of leg guards. The results of our study indicate significant opportunities for improvement in product design and the development of baseball leg guards along with an ergonomic design that considers the mobility of the knee, skin deformations is necessary to improve performance. The process followed in this study will be applicable to studies on other personal protective equipment for sports.

• 시큐리티연구
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• 제62호
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• pp.87-111
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• 2020

현재 국가주요시설 중 하나인 원자력발전소에서 근무하고 있는 특수경비원은 원자력시설 및 핵물질에 대한 위협으로부터 이를 안전하게 보호하기 위한 인적 방호의 역할을 수행하고 있다. 본 연구에서는 특수경비원의 임무완수에 필수적인 체력관리를 위한 체력훈련 프로그램을 개발하고자 하였다. 개발된 체력훈련 프로그램은 현재 근무 중인 특수경비원이 정호원, 최지웅(2019)이 제시한 원자력발전소 특수경비원 체력검정에 대비할 수 있도록 고안되었다. 연구진은 문헌분석, 연구진 회의, 전문가 회의 및 사전테스트를 진행하였으며, 이러한 과정을 거쳐 6주, 주 3회, 회 90분의 체력훈련 프로그램을 개발하였다. 한편 개발된 체력훈련 프로그램의 효과를 검증하기 위해 29명의 피험자(통제집단 15명, 운동집단 14명)를 대상으로 실험을 실시하였다. 구체적으로 운동집단을 대상으로 6주에 걸친 체력훈련 프로그램을 수행하였으며, 실험 전·후 피험자 전원을 대상으로 특수경비원 체력검정을 실시하였다. 실험 결과 개발된 체력훈련 프로그램의 수행이 특수경비원의 체력검정종목인 20m왕복오래달리기, 철봉에매달려무릎팔꿈치닿기, 20m중량왕복달리기, 메디슨볼뒤로던지기의 능력향상에 유의미한 효과가 있는 것으로 나타났다. 최근까지 특수한 환경 속에서 국민안전이라는 중대한 임무를 수행하고 있는 원자력발전소 특수경비원의 체력관리 및 감독 소홀에 대한 문제점들이 지적되고 있는 바, 본 연구가 제시한 체력관리 프로그램이 특수경비원들의 체력 유지·관리를 위한 실질적 대안이 되기를 기대한다.