• 한국산업보건학회지
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• 제15권3호
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• pp.153-159
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• 2005

The purpose of this study was to assess the ergonomic risks of lifting tasks in a marine diesel engine manufacturing industry using the National Institute for Occupational Safety and Health(NIOSH) Revised Lifting Equation(NLE). Average Lifting Index(LI=Weight of Load/Recommended Weight Limit) of a total number of 45 lifting tasks was $1.6{\pm}0.7$. The LIs were above 1 at 34 tasks(75.6%), and above 2 at 11 tasks(24.4%). Parts management showed the highest average LI value (LI=2.3) in all departments, which resulted from high frequency and heave load of lifting. The common and significant ergonomic risk factors in the processes were the heavy weight of diesel engine parts and the long horizontal distance. In addition, some lifting tasks had such potential risk factors as the long vertical distance, the high frequency of lifts or the long work duration.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.563-570
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• 2022

Industrialized and modular construction is a growing construction technique that can transfer a large portion of the construction process to off-site fabrication yards. This method of construction often involves the fabrication, pre-assembly, and transportation of massive and long volumetric modules. The module weight keeps increasing as the modules become more complete (with infill) to minimize the work at the site and, as higher productivity can be achieved at the fabrication shop. Thus, a volumetric module delivery gets more challenging and risky. Despite its importance, past research paid relatively insufficient attention to the problem related to the lifting of heavy modules. This can be a complex and time-consuming problem with multiple lifting for transportation-and-installation operations both in fabrication yard and jobsite, and require complex crane operations (sometimes, more than one crane) due to crane load capacity and load balance/stability. This study investigates this problem by focusing on the structural perspective of lifting such long volumetric modules through simulation studies. Various scenarios of lifting a weighty module from the top using four lifting cables attached to crane hooks (either a single crane or double crane) are simulated in SAP software. The simulations account for various factors pertaining to structural indices, e.g., bending stress and deflection, to identify a proper method of module lifting from a structural point of view. The method can identify differences in structural indices allowing identification of structural efficiency and safety levels during lifting, which further allows the selection of the number of cranes and location of lifting points.

• The Journal of Korean Physical Therapy
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• 제29권2호
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• pp.55-61
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• 2017

Purpose: The purpose of this study was to investigate the effects of a task-oriented upper arm exercise performed in a sitting position on either an unstable support surface or a stable support surface for children with cerebral palsy. Methods: We prospectively evaluated 18 children with cerebral palsy. Eight subjects were randomly assigned to each of the stable and unstable support surface groups. We performed the upper arm exercise three times a week for 6 weeks. To confirm the effects of the intervention, the berg balance scale test, modified functional reaching test (MFRT), timed up and go test (TUG), and Jebsen-Taylor hand function test were conducted before and after the study. Results: Significant differences were observed in MFRT and TUG between the experimental and control groups (p<0.05). In the Jebsen-Taylor hand function test, there were significant differences between the groups for the items picking up small objects, stacking checkers, lifting large light objects, and lifting large heavy objects (p<0.05), but not for writing and stimulation of feeding. Significant differences were observed between the groups in items of card turning, lifting large light objects, and lifting heavy objects. Conclusion: The purpose of this study was to evaluate the effectiveness of a task-oriented upper extremity exercise program for dynamic balance and hand function performed in a sitting position with either stable or unstable support by cerebral palsy patients. There were improvements in the two groups, but performing the exercise while sitting on an unstable support surface had a greater effect on dynamic balance and hand function than exercise while sitting on a stable supporting surface. The results of this study can be used to improve the daily lives of cerebral palsy patients.

• 한국화재소방학회논문지
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• 제34권3호
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• pp.110-115
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• 2020

본 연구는 소방훈련시 화학보호복 착용시 동작만족도를 분석하여 소방공무원의 안전을 위한 기초자료 제공을 목적으로 한다. 정적 동작만족도는 일반근무복에 비하여 화학보호복의 경우 21.7%~47.8% 정도 낮게 나타났다. 화학보호복 착용시 정적 동작자세에서는 고개 최대한 젖혀서 천장보기, 두팔 몸 앞에서 끌어안기, 비스듬히 굽혀 앉기, 과도하게 쪼그리고 앉기의 동작들이 낮게 나타났으며 통계적으로도 유의하게 낮은 결과를 보였다(p < .001). 동적 동작만족도는 일반근무복에 비하여 화학보호복의 경우 19.2%~47.8% 정도 낮게 나타났다. 화학보호복 착용시 동적 동작자세에서는 뛰기, 중량물 20 kg 허리까지 들어올리기, 중량물 20 kg 들어 1 m 옮기기, 들것 들고 앞으로 걷기, 들것 들고 뒤로 걷기의 동작들이 낮게 나타났으며 통계적으로도 유의하게 낮은 결과를 보였다(p < .001).

• 대한조선학회 특별논문집
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• 대한조선학회 2011년도 특별논문집
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• pp.5-11
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• 2011

In this paper, the dynamic response analysis of a floating crane with elastic booms and a cargo is performed. The objective is to consider the effects of the elastic boom in the lifting design stage. Governing equations of the motion for the system which consists of interconnected rigid and flexible bodies are derived based on the formulation of flexible multibody system dynamics. To model the boom as a flexible body, floating reference frame and nodal coordinates are used. Coupled surge, pitch, and heave motion of the floating crane with the cargo which has 3 degree of freedom is simulated by solving the equation numerically. Finally, the effects of the elastic boom for the lifting design that the floating crane is required to lift a heavy cargo are discussed by comparing the simulation result between with the elastic boom and with the rigid one.

• 한국안전학회지
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• 제38권4호
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• pp.60-67
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• 2023

Various lifting slings are used in domestic industrial sites depending on the purpose, form, and environment. Each sling has its characteristics, and safe lifting work is possible when its performance meets the regulations. Therefore, this study analyzed domestic and foreign regulations and guidelines related to chain slings. It identified significant problems by analyzing the chain-sling-related disaster cases. The current status of chain slings used by various industries and the ways to improve chain sling safety were studied. The major chain sling issues were: 1) employing improper components to chains, 2) having different safety coefficients between the regulation and industrial standards, and 3) using chains unsuitable for lifting purposes. Based on these issues, the following measures were proposed to improve chain sling work safety: 1) revise the safety coefficient requirements under the Regulations on Occupational Safety and Health Standards, 2) disseminate specialized sling courses, and 3) strengthen on-site chain slings-related training. In the future, this study is expected to minimize chain use mistakes by unifying the safety coefficient related to chain slings and recognizing the importance of correctly selecting components employed in the chain.

• Safety and Health at Work
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• 제2권3호
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• pp.236-242
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• 2011

Objectives: To determine the feasibility of predicting static and dynamic peak back-compressive forces based on (1) static back compressive force values at the lift origin and destination and (2) lifting speed. Methods: Ten male subjects performed symmetric mid-sagittal floor-to-shoulder, floor-to-waist, and waist-to-shoulder lifts at three different speeds (slow, medium, and fast), and with two different loads (light and heavy). Two-dimensional kinematics and kinetics were captured. Linear regression analyses were used to develop prediction equations, the amount of predictability, and significance for static and dynamic peak back-compressive forces based on a static origin and destination average (SODA) backcompressive force. Results: Static and dynamic peak back-compressive forces were highly predicted by the SODA, with R2 values ranging from 0.830 to 0.947. Slopes were significantly different between slow and fast lifting speeds (p < 0.05) for the dynamic peak prediction equations. The slope of the regression line for static prediction was significantly greater than one with a significant positive intercept value. Conclusion: SODA under-predict both static and dynamic peak back-compressive force values. Peak values are highly predictable and could be readily determined using back-compressive force assessments at the origin and destination of a lifting task. This could be valuable for enhancing job design and analysis in the workplace and for large-scale studies where a full analysis of each lifting task is not feasible.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.161-162
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• 2009

• The Journal of Korean Physical Therapy
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• 제4권1호
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• pp.59-67
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• 1992

This study was carried out by using questionnaires with 230 lumbago patients who visited the general hospitals, orthopedic clinics, neurosurgery clinics and physical treatment centers in Taequ. Korea for one month from December 20, 1991 to January 20, 1992. The result of this study is summarized as follows. 1. 203 patients consisted of 113 males and 90 females, while 65 patients were was which was the highest percentage. 2. The relation between their occupational properties and lumbago indicated that there was significant relation in their total employed period, job hours, monthly average incomes(P<0.01), job satisfaction, working posture, mental stress(P<0.01), excessive usage of bark during working, lifting of heavy thing and serious noises. 3. The relation between social properties and lunbago showed that there was a remarkable relation in their introspective character(P<0.05). daily average riding hour(P<0.05), smoking(P<0.01), drinking(P<0.01) and insufficient physical exercise. 4. The relation between the clinical properties and lunbago indicated that the lumbago was mainly caused by lifting the heavy thing, which was continued fur three months or longer. And, it was shown that they consider the lumbago as one of serious diseases. In addition. they positively evaluated their physical treatment. Therefore, it is required to accomplish the comprehensive treatment of this lumbago on the basis of the educational contents centering around its prevention by performing more suitable health education.

• 한국건설안전학회 논문집
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• 제2권2호
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• pp.63-69
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• 2019

현재 빌딩 건설 프로젝트의 규모가 점점 더 커지고 있다. 이에 따라 다른 양중 장비보다 생산성이 높은 타워크레인 사용이 지속적인 증가하고 있는 추세이다. 그러나 무거운 물건을 운반하는 장비는 임대료가 비싸고 비효율적으로 운영되고 있으며 양중 작업의 생산성 및 효율성이 저하된다는 문제가 있는 것으로 분석되었다. 따라서 본 연구에서는 우선 현장에서 비효율적으로 운영되는 타워크레인을 조사한 후 타워크레인 작업에 영향을 미치는 항목들에 대한 점검 목록을 작성했다. 그 후 현장 방문을 통해 타워 크레인 점검표를 종합적인 데이터 가치로 도출했다.