• 한국염색가공학회지
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• 제34권4호
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• pp.241-249
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• 2022

As for military backpacks in Korea, utility backpack products equipped with various functions along with comfort and convenience are being developed. As a result, the volume and weight of the backpack increase, and many lightweight studies of the materials forming the backpack are being conducted. This study is a basic study on frame lightweight using fiber-reinforced composites to deal with aluminum, a back frame that maintains the shape of a backpack and provides stability when worn by combatants. As is known, only fiber-reinforced composites have sufficient light weight and mechanical properties, but the mechanical properties were reviewed by drilling holes to maximize the light weight. Tensile strength and flexural strength were measured by drilling 6mm, 12mm, 18mm, and 24mm holes, and the tensile strength and flexural strength were measured when 1, 3, 5, and 7 holes of 12mm were increased. As a result, even when the number of holes was increased, tensile strength did not change significantly, and the flexural strength showed to be higher in the case of 3 holes and 5 holes than in the case of 1 hole.

• Physical Therapy Rehabilitation Science
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• 제12권2호
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• pp.155-160
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• 2023

Objective: The purpose of this study is to confirm a comparison of bag weight and applied location change on plantar pressure and gait parameters (stride time, stride length, cadence) of the 20s students. Design: One group cross-sectional design Methods: The subjects were measured in each condition. Each condition was no carrying a bag, carrying a 3kg bag, and a 6kg bag on the right shoulder, and walked on the gait analyzer. After the location of the bag was changed, measured when a 3kg backpack and a 6kg backpack was each carried on the back while walking. Results: There was a statistically significant difference in plantar pressure according to bag weight when carried on the right shoulder (p<0.05). As a result of the post-hoc analysis, carrying a 6kg bag was a significant difference between no carrying a bag and carrying a 3kg bag (p<0.05). There was no statistically significant difference in changes in stride time, stride length, and cadence. There was no statistically significant difference in plantar pressure and gait parameters according to backpack weight. Conclusions: As a result of this study, it is thought that it will be possible to present a method for the application of the correct bag on location and weight in 20s students, and to prevent and reduce muscle musculoskeletal system diseases caused by incorrect bag wearing.

• 대한임상전기생리학회지
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• 제9권1호
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• pp.29-34
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• 2011

Purpose : The purpose of this study was to determine the effect of book bag handling styles and types of footwear on muscle activation of erector spine muscles and calf muscles. Methods : Ten participants took off their book bags and used sneakers to walk on a treadmill for 30 minutes. The following day, 10 participants put on their backpack with 10% of the weight and used sneakers to walk on the treadmill for 30 minutes. On the last day, 10 participants put on their backpack with 10% of the weight and used formal shoes to walk on the treadmill for 30 minutes. After walking on the treadmill at 3 mph for thirty minutes, we measured muscle activation in erector spine muscles and calf muscles. Results : The results of this study showed the activation of the erector spine muscles and the calf muscles significantly increased when walking with a book bag and the activation of the erector spine muscles and the calf muscles significantly increased when walking in formal shoes. Conclusion : Using a backpack and formal shoes increase muscle activity of erector spine muscles and calf muscles. The results of this study indicate that not using a backpack and wearing sneakers are more beneficial than that using a backpack weighted 10% and wearing formal shoes and can be recommended to adult women by clinicians.

• 한국융합학회논문지
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• 제10권11호
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• pp.225-232
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• 2019

본 연구의 목적은 건강한 대학생을 대상으로 백팩 착용 유무 및 형태에 따른 몸통 하지 근 활성도 변인들의 차이점을 규명하는데 그 목적을 두고 있다. 26명의 건강한 성인이 연구에 참여하였다. 백팩의 무게 10%로 부하된 상태에서, 백팩을 착용하지 않은 상태, 일반적인 백팩을 착용한 상태, 모멘트 팔을 감소시키도록 고안된 백팩을 착용한 상태에서 몸통과 하지의 근활성도를 측정하였다. 배빗근육, 넙다리네갈래근, 앞정강근, 장딴지근의 근 활성도 분석을 위해 무선근전도 시스템을 사용하였다. 모멘트 팔을 감소시키도록 고안된 백팩을 착용한 상태에서 배빗근육, 넙다리네갈래근 그리고 장딴지근의 보행 구간에서 RVC에 변화가 통계학적으로 유의한 차이를 보였다. 그러므로, 백팩을 주로 사용하는 성인들에게 가방끈 조절을 적용하는 방법은 몸통과 다리근육의 활성에 긍정적인 측면을 제공한다는 것을 나타내며, 추후 가방의 디자인과 착용방법에 대한 지속적인 가방융합개발이 필요할 것이다.

• 한국컴퓨터정보학회논문지
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• 제19권3호
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• pp.155-161
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• 2014

본 연구의 목적은 보병용 휴대 배낭 설계를 위하여 인체공학적인 물자취급 중량을 검토하여 휴대 및 이동성능에 기초한 한계하중을 분석하는데있다. 제품설계시 인체공학적 설계가이드라인과 운용현황을 조사분석하여 효율적인 운용성능을 위한 기초자료로 제공하고자 한다. 본 연구에서는 인력물자취급시 역사적 관점에서 생리학적 연구방법, 생체역학적 연구방법, 인체심리학적 연구방법들을 검토하여 보병용 휴대배낭의 휴대성 및 이동성을 분석하였다. 휴대성과 이동성 간의 관계를 분석한 결과, 단거리의 짧은 기동거리에서는 생체역학적 기준치를, 1-2시간의 중간인 이동에서는 인체심리학적 기준치를, 4시간 혹은 그 이상의 장거리에서는 생리학적 기준치를 적용하여 각각의 가이드라인들을 상호 절충하는 것이 필요한 것으로 판단된다. 본 연구에서는 보병의 물자취급시 4가지 연구방법을 제안하였다. 이러한 기존의 설계 가이드라인을 분석한 결과, 병사의 인체사이즈 측면에서는 5%tile의 경우 -091kg으로 여유중량이 부족하지만, 95%tile에서는 34.17kg까지 여유중량이 발생하는 것으로 판단된다. 이러한 연구결과는 물자취급시 편하고, 효율적인 운용성능을 창출하기 위해서 휴대중량과 이동거리에 따라 여유중량을 관리해야 할 것으로 판단된다.

• 한국측량학회지
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• 제35권2호
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• pp.91-102
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• 2017

Backpack-mounted mapping system is firstly introduced for flexible movement in indoor spaces where satellite-based localization is not available. With the achieved advances in miniaturization and weight reduction, use of LiDAR (Light Detection and Ranging) sensors in mobile platforms has been increasing, and indeed, they have provided high-precision information on indoor environments and their surroundings. Previous research on the development of backpack-mounted mapping systems, has concentrated mostly on the improvement of data processing methods or algorithms, whereas practical system components have been determined empirically. Thus, in the present study, a simulator for a LiDAR sensor (Velodyne VLP-16), was developed for comparison of the effects of diverse conditions on the backpack system and its operation. The simulated data was analyzed by visual inspection and comparison of the data sets' statistics, which differed according to the LiDAR arrangement and moving speed. Also, the data was used as input to a point-cloud registration algorithm, ICP (Iterative Closest Point), to validate its applicability as pre-analysis data. In fact, the results indicated centimeter-level accuracy, thus demonstrating the potentials of simulation data to be utilized as a tool for performance comparison of pointdata processing methods.

• 한국운동역학회지
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• 제16권2호
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• pp.25-35
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• 2006

The purpose of this study was to investigate the shock attenuation mechanisms while varying the loads in a backpack during drop landing. Ten subjects (age: $22.8{\pm}3.6$, height: $173.5{\pm}4.3$, weight: $70.4{\pm}5.2$) performed drop landing under five varying loads (0, 5kg. 10kg. 20kg. 30kg). By employing two cameras (Sony VX2100) the following kinematic variables (phase time, joint rotational angle and velocity of ankle, knee and hip) were calculated by applying 2D motion analysis. Additional data, i.e. max vertical ground force (VGRF) and acceleration, was acquired by using two AMTI Force plates and a Noraxon Inline Accelerometer Sensor. Through analysing the power spectrum density (PSD), drop landing patterns were classified into four groups and each group was discovered to have a different shock attenuation mechanism. The first pattern that appeared at landing was that the right leg absorbed most of the shock attenuation. The second pattern to appear was that subject quickly transferred the load from the right leg to the left leg as quickly as possible. Thus, this illustrated that two shock attenuation mechanisms occurred during drop landing under varying load conditions.

• 대한물리치료과학회지
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• 제18권3호
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• pp.71-78
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• 2011

Purpose : The purpose of this study found change that caused by various form and weight of bag. So we investigated how these things change the shoulder altitude and space between external acoustic pore and lateral malleolus and also plantar pressure. Method : We measured two different way for this study. One was backpack with 5, 10kg and another one was shoulder pack with same weight. Each trial was 10 seconds in duration with static stance posture. With these experiments, we checked space between plantar pressure, shoulder altitude, external acoustic pore and lateral malleolus with EMED system and GPS. We analyzed these results with PASW(SPSS) statistics 18.0. Result : In conclusion, there were no significantly differences in shoulder altitude by weight of pack, but average of plantar pressure and space between external acoustic pore and lateral malleolus was increased.

• 대한물리치료과학회지
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• 제16권2호
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• pp.11-17
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• 2009

Background: The purpose of this study was to investigate the effects of the body alignment on the type and weight of the bag. Methods: The Subjects(n=62) measured posture alignment and make out the questionnaire. The questionnaire item was type of the bag, weight of the bag, side which carries the bag, and time to carry the bag. The posture alignment measured by global posture system(GPS). GPS Measurement was ASIA, acromion process, medial malleolus on Frontal plane, ear, shoulder joint, knee joint, lateral malleolus on sagittal plane, and trunk rotation on transverse plane. Results: The backpack and shoulder bag was no significant. The width of the strap bag was not significant. The side which carries on shoulder bag was statistical significance(p<.05). The time to carry the bag was statistical significance on change of posture(p<.05). A bag weight was no significant. Conclusion: This research provides the direction and carry the bag in time for the posture. This study showed that type and weight of bag does affect body alignment. This indicates that there is an interaction that plays a crucial roles in the type and weight of bag and the body alignment.

• Child Health Nursing Research
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• 제21권4호
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• pp.320-330
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• 2015

Purpose: The purpose of this study was to investigate the use of schoolbags and the prevalence of musculoskeletal symptoms among elementary school children and to identify factors associated with relative schoolbag weight and musculoskeletal symptoms. Methods: A descriptive correlation study was conducted with 228 elementary school children in grades 4-6. A self-administered questionnaire was used for data collection. Descriptive statistics, t-test, ANOVA, $x^2$-test or Fisher's exact test, logistic regression analysis were used for data analysis. Results: Mean relative schoolbag weight (RSW) was 6.40%. Among participants, 13.2% carried more than 10% of their RSW. Only 49.6% of participants organized the contents in their school backpack correctly. Musculoskeletal symptoms were reported by 42.5% of participants. Results from logistic regression analysis identified grade was a significant factor predicting RSW, and gender, RSW, and using a locker were significant factors predicting musculoskeletal symptoms among schoolchildren. Conclusion: Although RSW of school children in this study was within the currently recommended load limit, a considerable proportion of school children were not following guidelines for safe schoolbag use. An effective schoolbag safety campaign for parents, students, and teachers needs to be developed and evaluated to prevent possible musculoskeletal symptoms related to schoolbag use.