• 한국해양공학회지
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• 제14권1호
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• pp.17-22
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• 2000

This study focuses on a simple analytical approach to calculate crane lifting forces for a sunken ship. The method takes into account the relation of lifting forces acting in wire rope slings to the inclination of the vessel including the effect of lug positions. The importance of the sunken ship salvage is explained from the statistics of ship casualties during last 15 years. Euler angles are introduced to represent the inclination of a sunken ship in developing the static force and moment equations,. Three dimensional examples with one redundant degree of freedom for a GT1500 oil tanker are analyzed and the results show that the information obtained by the method could be useful to salvors to conduct salvage work.

• 한국직업건강간호학회지
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• 제7권2호
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• pp.130-135
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• 1998

To investigate the working characteristics of the workers by place of duty, a study was carried out among 591 male workers aged 20-55 employed in an automobile industry in Korea. Workers participated to this study were divided into low back pain(LBP) and control group, according to the self-reports by written questionnaires. Work factors and complaint rates of low back pain were compared to the work places. The results were as follows ; 1) The complaint rates of low back pain were 49.2%(292 men) as a whole, 58.6%(34 men) in Production Control Department I, 50.2%(120 men) in Stamping Tool Department, 46.9%(138 men) in Bus Department. 2) Lifting and earring work of individual workers were directly associated with low back pain. Frequency of lifting and carring work is higher in the Final Body Section(Production Dept. I) and Body I Section(Bus Dept.). 3) LBP group were more frequently involved in working in awkward position(Quality Control Section of Stamping Tool Dept.), bending(Body I Section of Bus Dept.) and twisting posture(Sash Section and Body I Section of Bus Dept.). 4 )Workers exposed to vibration during working shows the higher complaint rate of low back pain.

• Safety and Health at Work
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• 제3권1호
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• pp.52-57
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• 2012

Objectives: Lifting heavy weights involves the Valsalva manoeuvre, which leads to intraocular pressure spikes. We used data from a case-control study to further investigate the hypothesis that occupational lifting is a risk factor for retinal detachment. Methods: The study population included 48 cases (patients operated for retinal detachment) and 84 controls (outpatients attending an eye clinic). The odds ratios (OR) of idiopathic retinal detachment were estimated with a logistic regression model (adjusted for age, sex and body mass index). Three indexes were used to examine exposure to lifting; 1) maximum load lifted, 2) average weekly lifting, 3) lifelong cumulative lifting. Results: For all indexes, the most exposed subjects showed an increased risk of retinal detachment compared with the unexposed (index 1: OR 3.57, 95% confidence interval [CI] 1.21-10.48; index 2: OR 3.24, 95% CI 1.32-7.97; index 3: OR 2.23, 95% CI 1.27-8.74) and dose-response relationships were apparent. Conclusion: These results reinforce the hypothesis that heavy occupational lifting may be a relevant risk factor for retinal detachment.

• 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.

• 한국건축시공학회지
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• 제16권2호
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• pp.151-159
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• 2016

건설프로젝트에서 요구되는 중요한 장비 중 하나는 타워크레인 이다. 특히, 대부분의 고층건물 공사에서는 자재들의 이동작업들을 수행하기 위해 타워크레인이 더욱 요구되어진다. 따라서 타워크레인의 양중계획은 공사기간과 비용의 측면에서도 중요하다 할 수 있다. 하지만, 건설현장 대부분의 양중계획은 여전히 합리적인 작업의 분석없이 현장 관리자들의 경험과 직관에 의존하여 행해지고 있다. Dependency structure matrix (DSM)는 CPM과 Pert 같은 기존의 툴과는 다르게 작업 활동 순서 계획과 정보관리를 하는데 있어서 유용한 툴이다. 본 연구는 타워크레인의 양중 관리를 향상시키기 위하여 실제 건설 현장의 Case study를 통해 타워크레인 양중관리의 새로운 틀을 DSM을 이용하여 제시 할 것이다. DSM을 이용한 T/C의 양중계획의 Case study를 통해 나타난 결과는 기준층 양중 계획에 있어서 T/C의 양중계획을 최적화 시키는데 매우 유용하다는 결론을 보여주었다.

• 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.

• 한국안전학회지
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• 제20권1호
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• pp.148-152
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• 2005

The purpose of this paper is to investigate risk factors and ergonomically improve the manufacturing lines of compressors for prevention of work-related musculoskeletal disorders, enhancement of productivity, and workers satisfaction We executed questionnaire survey, ergonomic risk factors investigation of manufacturing lines and ergonomic intervention of work methods, workplace and hand tools. The results of the questionnaire showed that $7.9\%$ of respondents were positive in WMSDs symptom survey. In ergonomic evaluation, the analysis methods such as RULA and NIOSH lifting equation were used and 28 processes in the lines were evaluated to be potentially hazardous. We ergonomically improved the processes to reduce potential WMSDs hazards : manual material handling, carts, work tables, transport methods, working posture and hand tools.

• 한국콘텐츠학회논문지
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• 제9권2호
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• pp.252-260
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• 2009

본 연구는 신체능력향상프로그램이 다운증후군 성인의 작업강도에 미치는 영향을 알아보고자 하였다. 이를 위해, 8명의 다운증후군 성인이 신체능력향상프로그램에 참가하고 작업강도를 측정하였다. 신체능력 향상프로그램은 악력, 들어올리기, 운반 운동으로 구성되었으며, 주 1회 2시간 씩 12주에 걸쳐 진행되었다. 프로그램 실시 전과 비교해 보면, 참가자들은 우측 악력과 들어올림 능력에서는 유의한 변화를 나타냈고 운반 능력에서는 유의한 변화가 없었다. 들어올림에서는 2명의 작업강도 수준이 보통 작업에서 힘든 작업의 수준을 나타냈다. 운반에서는 1명은 아주 가벼운 작업에서 보통 작업으로 그리고 2명은 가벼운 작업에서 보통 작업 수준으로 변화를 나타냈다. 이러한 결과는 신체능력향상프로그램이 다운증후군 성인의 작업강도 향상에 유용함을 제시하고 있다.

• Journal of Preventive Medicine and Public Health
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• 제26권1호
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• pp.20-36
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• 1993

Work-related low back pain is one of the major factors that cause the loss of working power especially in actively working age, therefore controlling the work-related low back pain is one of the major issues in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the efficient control program of the work-related low back pain. The subjects were male workers employed at the manufacturing industry in Pusan with longer than 6 months' working duration. The data was collected by self-reported questionnaire and interview from May 1 to October 31,1992. The contents of questionnaire were as follows:. the experience of low back pain within the recent one month, general characteristics(age, marital status, education level, religion, regular exercise), physical characteristics(height, weight), employment status(working duration, daily working hours, rest during work, satis(action fur the job), type of work and working environments(posture, forward bending, lifting and movement, satisfaction for table and chair). The result was analyzed for 608 entire respondents by case-control comparative method. The number of cases was 152 with a history of work-related low back pain, so the relative frequency of self-reported work-related low back pain was 25.0%, and the number of controls was 344 without any history of low back pain. As a result, two characteristics of the employment status(working duration, satisfaction fur the job) and all characteristics of type of work and working environments showed a statistical significance between the case and control groups(p<0.01). The Oddb ratios of these variables for Work-related low back pain were calculated. They were 7.88 for the satisfaction fur chair, 7.86 for lifting and movement,3.31 for satisfaction for table, and 2.22 fur bending forward(p<0.01). And for the multivariate logistic regression analysis confirmed that unsatisfaction for table was independent risk factor for Work-related low back pain. In summary, though this study was based upon the self-reported questionnaire and the subjective complaints, the satisfaction for chair, lifting and movement, satisfaction for table, and bending forward concerned with the type of work and working environments were considered as the main factors causing the work-related low back pain, and the work-related low back pain may be preventable by the ergonomic control of these factors.

• 대한한의학원전학회지
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• 제29권2호
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• pp.135-150
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• 2016

Objectives : KangHaiChengZhiLun (亢害承制論; If Excess Brings Harm, Lifing Qi (承氣) Restrains) was originally a theory that explained how the realms of nature remain in harmony and equilibrium. It later became an important theory for clinical trials of Traditional Chinese Medicine, explaining the physiological and pathological mechanism. Methods : The researcher considered all the annotations and the original text of SuWen(素問), LiuWeiZhiDaLun(六微旨大論) and theories of medical practitioners who applied KangHaiChengZhiLun(亢害承制論) to their clinical trials. Results & Conclusions : Wangbing (王氷) went with a theory that phenomena of Lifting Qi (承氣) take place in the realms of nature when Qi (氣) flourishes. In XinJiaoZheng(新校正), he wrote about two theories: one was that Six Kinds of Natural Factors (六氣) first work as the main Qi (本氣) but later bring about Lifting Qi. (終見下承之氣說); the other was that excessive Stagnation Qi (鬱氣) can be exploded and invite another accompanying Qi, Lifting Qi. (甚者兼其下承之氣說) Liuwansu (劉完素) had a theory that if Six Kinds of Natural Factors go disproportionately excessive, it becomes accompanied by imaginary Qi (假象) that conquers self. (反兼勝己之化說) $Wangl{\ddot{u}}$(王履) maintained that Lifting Qi usually works as a means to prevent Six Kinds of Natural Factors (六氣) from becoming rampant; but when Six Kinds of Natural Factors become overly excessive, Lifting Qi restrains them in order to maintain equilibrium. (防之與克勝說) Yutuan explained that since Excessive Qi (亢氣) does damage to the mother of Lifting Qi, Lifting Qi restrains Excessive Qi to protect Original Qi (元氣), its mother. (護救承者之元氣說) Gongtingxian was in favor of two theories: one argued that causes and symptoms of a disease differ from each other. (體用不同說); the other said that diseases are naturally cured if the patient finds out the time when Lifting Qi gains strength. (得承之時自愈說) Mashi (馬蒔) had a theory that Lifting Qi is generated when Six Kinds of Natural Factors are prosperous and reveals itself when its season comes. (極則生承氣 至本位著說) Zhangjiebin (張介賓) asserted that when Six Kinds of Natural Factors are thriving, Lifting Qi, as a restraining force, is generated to disperse the thriving natural factors and leads to a new one. (前之退而後之進說) Zhangqi (張琦)'s argument was that if Lifting Qi restrains the main Qi, a son of the main Qi is generated and every four season goes in harmony. (承氣制則生化說) Hemengyao (何夢瑤) had an argument that a son of the restrained Qi succeeds to its father and later achieves equilibrium by restraining Excessive Qi. (被克承父 制之平衡說).