• Proceedings of the ESK Conference
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• 1996.10a
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• pp.3-6
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• 1996

Cumulative trauma disorders (CTDs) are becoming a major health hazard among phone directory service operators. In order to clarify the causes and to reduce the occurrence of CTDs, a site survey was done. The survey includes observation of the task and the working environment. Also, operators were closely examined and diagnosed to understand the exact causes of CTDs. Different types of CTDs were identified and the most cases were developed in a two or three-years after using new VDT-based workstations. The various design features of workstation aggravated the developemtn of CTDs together with the intense workload. The ergonomic resolutions were suggested based upon these observations.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.165-168
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• 2000

Engine noise is one of the major causes of the interior noise, and so has been studied in various ways in recent days. Recently air induction noise has been extensively studied to reduce the engine noise. Conventional method to reduce the noise is adding several resonators to the induction system. However this causes a reduction of engine output power and an increase of fuel consumption. Thus in this study, the feasibility of applying the active noise control to the induction system is studied to the overcome the above disadvantage.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.2 no.1
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• pp.24-30
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• 1986

The vocal nodule is one of the major causes of hoarseness. The patholphysiologic mechanism of the vocal nodule is relatively well-known. Chronic mechanical stimuli, such as vocal abuse, causes vocal nodule by a tissue reaction of the vocal cords. Among the 841 patients, who visited the Vocal Dynamic Laboratory at Severance Hospital complaining of the dysphonia between the period of May 1981- May 1985, 169 patients were selected who were diagnosed as vocal nodule by indirect laryngoscopy and a series of phoniatric examination. (omitted)

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.502-506
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• 2007

Railway accidents/incidents occur because of many reasons. Human error by the railway staff or personnel takes a major part of those reasons. In order to reduce and prevent railway accidents/incidents, appropriate measures should be developed to remove root causes induced in human error. A systematic study for analysing causes of human errors and for developing an effective management is necessary. Detailed analysis of the railway traffic signaller's tasks should be preferentially performed for this purpose. This paper introduces the results of analysis for the types and characteristics of the railway traffic signaller's tasks. As a result of the analysis, the railway traffic signaller's tasks can be decomposed into 24 tasks in total, and also be divided into the general task and the emergency task. The railway traffic signaller's tasks are characterized to require continual confirmation and observation activities, and sometimes immediate decision and action.

• Journal of the Korea Furniture Society
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• v.17 no.3
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• pp.45-55
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• 2006

The change of consumers' lifestyles causes frequent study on beds along with growth of economy, improvement of education and increase of dwelling in new towns and nuclear family. Beds are frequently developed in recent years since consumers' lifestyles increasingly change caused by transformation of types of dwelling, influence of western lifestyle, and increase uses of a bed. Also, this transformation causes needs for research on bed designs. A Bed is an essential item in a life since people spend one third of a day in Also, in contemporary, the ages of consumers are varied from infants to seniors. The study examines the importance of beds which playa major role in households. Moreover, the purpose of this study of beds focused on surface materials, colors, and designs is suggesting bases for future developments.

• Journal of the Korea Safety Management & Science
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• v.6 no.4
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• pp.39-46
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• 2004

The Study lay Emphasised on to Investigate Human Related Causes of a Pointed End Equipment Accident and the Basic data for Analyzing Human-Error Prevention Program. Peter Son's Model of Human-Error Accident Causation and Cooper's Model of Safety Culture Were Applied to Analyze the Severe Cause of a Pointed End Equipment for Last 5 Years. Through to Analyzing the Cause of Equipment Accident of Human-Error, Expert's Opinion and Experience Theory Method was Reflected. The Analyses Showed What the Immature and Inexperient Error Were Major Causes of a Pointed and Equipment Accident. The Cause of Human-Error was Found with Respect to Human, Tasks, Acknowledge, Organization.

• Journal of the Korean Society of Safety
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• v.16 no.4
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• pp.153-159
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• 2001

Recently, the underground reinforced concrete(RC) box structures have been increasingly built in Korea. In such structures, the heat of hydration may cause serious cracking problems. The RC box structures are classified in this category that needs much attention to control the hydration heat during construction, which causes the restraining effects on the boundaries. The purpose of the present study is to develop the rational construction method to control the thermal cracking problem of the box structures. In this study, the causes and mechanism of thermal cracking according to construction stages in the RC box structures are thoroughly analyzed. The major influencing variables are studied through the finite element analysis which affect the thermal cracking of RC box structures. The research results of the present study can be efficiently used for the control of cracking of box structures during construction stages.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.311-318
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• 2004

The Study lay Emphasised on to Investigate Human Related Causes of a Pointed End Equipment Accident and the Basic data for Analyzing Human-Error Prevention Program. Peter Son's Model of Human-Error Accident Causation and Cooper's Model of Safety Culture Were Applied to Analyze the Severe Cause of a Pointed End Equipment for Last 5 Years. Through to Analyzing the Cause of Equipment Accident of Human-Error, Expert's Opinion and Experience theory Method was Reflected. The Analyses Showed What the Immature and Inexperient Error Were Major Causes of a Pointed and Equipment Accident The Cause of Human-Error was Found with Respect to Human, Tasks, Acknowledge, Organization.

• Proceedings of the Safety Management and Science Conference
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• 1999.11a
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• pp.217-236
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• 1999

Engineering process control (EPC) is one of the techniques very widely used in process. EPC is based on control theory which aims at keeping the process on target. Statistical process control (SPC), also known as statistical process monitoring. The main purpose of SPC is to look for assignable causes (variability) in the process data. The combined SPC/EPC scheme is gaining recognition in the process industries where the process frequently experiences a drifting mean. This paper aims to study the difference between SPC and EPC in simple terms and presents a case study that demonstrates successful integration of SPC and EPC for a product in drifting industry. Statistical process control (SPC) monitoring of the special causes of a process, along with engineering feedback control such as proportional-integral-derivative (PID) control, is a major tool for on-line quality improvement.

• Corrosion Science and Technology
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• v.13 no.1
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• pp.6-14
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• 2014

Copper metal is widely used in tubes installed in sprinkler water services because of its excellent corrosion resistance. Copper corrosion is considered to be insignificant in water system and the incident of copper pipeline failure is relatively low. However, pitting corrosion is a major problem with all copper tubes. In this study, leaked sprinkler copper tubes were collected from three different locations and examined on the causes of pitting corrosion of copper tubes in sprinkler water plumbing systems. Electrochemical tests such as potentiodynamic polarization, as well as surface and chemical analyses were performed. Results show that pitting corrosion of copper tubes were found as Type I pitting that the carbon film formed on the copper tubes have a harmful effects, causing the pinhole failure in the pipe and resulting in leakage of water. The contermeasures on Type I pitting corrosion of copper tubes were proposed.