• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.209-214
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• 1997

본 논문은 인력운반작업(Manual Materials Handling)과 관련된 위험요인을 파악하여 안전한 작업을 설계할 수 있는 기준을 설정하는 것을 목표로 하고 있으며, 이러한 목표를 달성하기 위하여 운수유통업을 중심으로 현장에서의 인력운반 작업에 대한 실증적인 조사를 실시하여 기존에 알려진 인력운반의 위험요인 이외에 작업자들의 행동적인 위험요인이나 그밖에 그간 고려되지 못하였던 실질적인 위험인자들을 밝혀내고자 하였으며 최근에 들어 인력운반에 있어 새로운 위험평가 기법으로 사용되고 있는 LMM(Lumbar Motion Monitor)을 가능하게 할 수 있는 electrogoniometric system을 구성하여 새로운 방범으로 인력운반의 위험성을 평가 하고자 하였다. (중략)

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.647-650
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• 1996

Manual materials handling and improper working postures are known to be a major cause fo low back injuries, which are one of the major problems in the economic and public health aspects. In this study, two machine repair shops of a manufacturing company in Pohang are selected to investigate the potential hazards of low back injuries. Questionnaire study and worker's strength evaluation are conducted and the results are analyzed. Field workers performing the relatively low stressful jobs were also studied as a control group for comparison with the workers performing the tasks under study.

• Proceedings of the ESK Conference
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• 1994.04a
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• pp.52-63
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• 1994

산업현장에서 산업재해의 주요한 요인이 되는 중량물 수운반 활동시 작업자가 안전 하게 작업을 행하면서도 최적허용중량을 결정하기위한 연구는 주어진 작업조건하에 서 인양되는 최대중량을 결정하기 위한 기준으로서 척추에 가해지는 압력을 이용하는 생체역학적 접근법, 주어진 작업조건하에서 인양되는 최대중량을 결정하기 위한 기준 으로서 에너지 소모량을 이용하는 생리학적 접근법, 주어진 작업조건하에서사람이 인 양할 수 있는 최대중량을 결정하는 기준으로서 피실험자에의해서 인지되는 힘든 정도를 이용하는 정신물리학적 접근법 등으로수행하여 왔다.

• Proceedings of the ESK Conference
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• 1994.04a
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• pp.64-71
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• 1994

최근 일상생활이나 산업현장에서 생산공정의 기계화 또는 자동화로 인하여 수 작업이 많이 감소하였으나 아직도 정형화 되지 못한 물건의 운반, 부품조립 등 위 험요소를 내포한 여러가지 형태로 상지 동작(arm exertion)이 요구되는 인력운반 (manual material handling) 작업이 실제 작업현장에서 행새지고 있는 실정이며, 이러한 작업으로 인해 작업자들의 근골격계 부상으로신체장애의 사례가 늘어나고 있다.

• Proceedings of the ESK Conference
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• 1996.04a
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• pp.104-112
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• 1996

This paper investigates the job-related low back pains (LBP) in Kuro industrial complex where the manufacturing industries are prevailing. The accident compensation claims during 1992 to 1994 were reviewed and total of 726 LBP claims were analyzed among 7920 compensation claims. A LBP database was constructed to analyze the LBP profiles of this area. The most frequent cause of LBPs was the manual materials handling related lifting, lowering, carrying, pushing or pulling(45.9%) and the second-most frequent cause was fall and slip (29.8%) and collision (7.9%) was the following cause of the LBP.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.3
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• pp.239-247
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• 2008

Low back disorders (LBDs) have been the most common musculoskeletal problem in Korean workplaces. It affects many workers, and is associated with high costs to many companies as well as the individual, which can negatively influence even the quality of life of workers. The _evaluation of low back disorder risk associated with manual materials handling tasks can be performed using variety of ergonomic assessment tools such as National Institute for Occupational Safety and Health (NIOSH) Revised Lifting Equation (NLE), the Washington Administrative Code 296-62-0517 (WAC), the Snook Tables etc. But most of these tools provide limited information for choosing the most appropriate assessment method for a particular job and in finding out advantage and disadvantage of the methods, and few have been assessed for their predictive ability. The focus of this study was to _evaluate spinal loads in real time with lifting and pulling heavy cow leathers in variety of postures. Data for estimating mean trunk motions were collected as employees did their work at the job site, using the Lumbar Motion Monitor. Eight employees (2 males, 6 females) were selected in this study, in which the load weight and the vertical start and destination heights of the activity remained constant throughout the task. Variance components (three dimensional spaces) of mean trunk kinematic measures were estimated in a hierarchical design. They were used to compute velocity and acceleration of multiple employees performing the same task and to repetitive movements within a task. Therefore, a results of this study could be used as a quantitative, objective measure to design the workplace so that the risk of occupationally related low back disorder should be minimized.

• Journal of Korean Elementary Science Education
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• v.26 no.2
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• pp.161-170
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• 2007

This study aims at helping us improve the methods used to teach elementary school students how to handle experimental apparatus by examining their manual skills and their understanding of the alcohol lamp, spuit and thermometer. To evaluate their ability to handle each experimental apparatus, a practical skills test and knowledge evaluation sheets were developed. The evaluation was carried out with 270 students from 2 classes each in the 3rd, 4th, 5th and 6th grade of D Elementary School located in Daejeon City. For their handling ability of the alcohol lamp, the results for the practical skills test showed that the students had a very low ability in placing objects in the center of the apparatus for safe use and also in adjusting the height of the trivet to place objects so that they contact the outer flames correctly. For the spuit, the pass rate of the skills test was generally low in regards to how students should grasp a spuit and the timing and method of depressing the rubber part before dipping it into liquid. For the thermometer, on the other hand, the pass rate was relatively high in every respect. The knowledge evaluation results for the use of experimental apparatus showed a very high rate of correct answers for alcohol lamps and thermometers. The test results for spoils also produced a relatively high rate of correct answers, with the exception of the test item regarding the way that students should grasp them.

• Journal of Korea Society of Industrial Information Systems
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• v.5 no.1
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• pp.77-86
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• 2000

Even manual materials handling tasks(MMHT) is decreasing by adopt of automatic manufacturing system & transportation supporting machine because of increase of productivity, wage lack of labor, safety, in fact working at inclined & complicated slope such as farm, orchard, harbor loading & unloading, logging place and mining place can't be substituted by machine perfectly. So, workers should do MMHT at this place by themselves, lifting on slope can cause much of hazard, include falling. Keeping balance net to slip can be a reason of low back pain(LBP) by overloaded musculoskeletal system but, there's no enough study about lift on slope. Therefore, In this study, we assessed and analyzed change of center of pressure(COP) when lifting on slope by force platform. The result showed that the length lengthen as increasing angle of slope. Especially, the length extremely increased over 15°. Through These basic result, present proper angle boundary, prevent industrial accidents and give proper data not only lifting but also pushing and pulling on slope someday.

• 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.

• Journal of the Korea Safety Management & Science
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• v.16 no.4
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• pp.371-378
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• 2014

Manual materials handling tasks are the main risk factors for the work-related musculoskeletal disorders. Many assistant tools for manual materials handling are being used in various kind of industries. One of them is a 4-wheeled cart which is widely used in manufacturing factories, hospitals, etc. The major force required to control the 4-wheeled cart is pushing and pulling. There are two types of handles being used for the 4-wheeled cart : vertical type (two vertical handles), and horizontal type (one horizontal handle). This study tried to investigate the pushing forces and subjective discomforts (hand/writst, shoulder, low back, and overall) of the two handle types with different handle height and distance conditions. Twelve healthy male students (mean age = 23.4 years) participated in the experiment. The independent variables were handle angle (horizontal, vertical), handle height (low, medium, high), and handle distance (narrow, medium, wide). The full factorial design was used for the experiment and the maximum pushing forces were measured in 18 different conditions ($2{\times}3{\times}3$). Analysis of variance (ANOVA) procedure was conducted to test the effects of the independent variables on the pushing force and discomfort levels. Handle height and angle were found to be the critical design factors that affect the maximal pushing forces and subjective discomfort. In the middle height, subjects exerted higher pushing forces, and experience lower discomfort levels compared to the high, and low height. There was no statistical influence of the handle distance to the pushing forces and subjective discomfort levels. It was found out that the effects of the handle angle (horizontal and vertical) on both pushing force and subjective discomfort were statistically significant (p < 0.05). The vertical handle revealed higher pushing force and lower discomfort level than the horizontal handle. The reason for that was thought to be the different postures of the hand when grasping the handles. The horizontal handle induced pronaton of the hand and made hand posture more deviated from the neutral position.