• 대한인간공학회지
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• 제35권3호
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• pp.155-163
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• 2016

Objective: This study aims to draw the characteristics of occupational accidents occurred in cabling work, and assess accident severity based on occupational injury data. Background: Accident factors and accident risk are different by the place of work in cabling work. Field managers require information on accident prevention that can be easily understood by workers. However, there has been a lack of studies that focus on cabling work in Korea. Method: This study classifies 450 injured persons caused in cabling work by process, and analyzes the characteristics of occupational injuries from the aspects of age, work experience and accident type. This study also analyzes accident frequency and severity of injury. Results: Results show that preparing/finishing (33.3%) was the most common type of cabling process in injuries, followed by maintenance (28.4%), routing/income (23.1%) and wiring/installation (15.1%) process. The critical incidents in the level of risk management were falls from height in the routing/incoming process, and falls from height in the maintenance process. And, incidents ranked as 'High' level of risk management were slips and trips, fall from height and vehicle incident in the preparing/finishing process, and fall from height in the wiring/installation process. Conclusion and Application: The relative frequency of accident and its severity by working process serve as important information for accident prevention, and are critical for determining priorities in preventive measures.

• 건축역사연구
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• 제10권1호
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• pp.25-40
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• 2001

Since the 17th century, the society of Chosun Dynasty belonged to a period of rapid transition in many fields. As the building is a result produced on the basis of a society and economy, the general transition in a society is to be reflected into a process of building construction. Therefore an understanding or estimate of a building can be guaranteed by research of a process of building construction. Economic base factors in its process consist of material, cost, manpower, and operation system, etc. to be committed to the construction. On the premise, this paper is to examine the production of wood members and the calculation of the amount of raw woods in a process of woodwork in the construction of the government managed buildings in the late of Chosun dynasty. Construction reports, job slips, written estimates, and other documents in those days are examined for the study. To classify raw woods according to a standard size was aimed to a material management appropriately to apply each them to building size or its member size. The way to select a list of raw woods applicable to each member size, and to calculate the amount of the demanded wood was much more improved with 'Injungjeon-yeongkweon' in the year 1805 at the turning point than 'Hwaseong-seongyuk' in the year 1796. The improvement of material management brought to overcome a shortage of the amount supplied from forest preserve, and to a rationalization of building construction.

• 건축역사연구
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• 제8권1호
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• pp.9-28
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• 1999

Broadly speaking, this paper is concentrated on the trimming of the wood demanded for the palace, constructed in the 2nd half of the Choseon Dynasty. To be concrete, this is the study on the craftman and craftmanship corncerned with the trimming of the wood, its system, and terms of payment of his wages, Construction reports, financial reports, job slips, written estimates, bills for payment, and other documents in those days are examined for the study. Following conclusions have been reached through the study. 1) The operation system of whole construction office and its suboffice was very specialized and systematized from the early 19th century. 2) The craftman engaged in trimming of the wood was subdivided by work function. 3) The craftman for its first trimming, i.e. 'keojang' or 'seonjang' had been treated as a speacial labor recruited to the mid-l8th century, after that, was enrolled into the craftman. 4) A unit cost of its first trimming was firstly appropriated into the reconstruction of the Kyongwoon Palace in the early 20th century, and it was very subdivided for a personnel management. 5) Contract works were widely applied to all workers engaged in the reconstruction for an efficiency of the accomplishments.

• 한국비블리아학회지
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• 제4권1호
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• pp.103-127
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• 1980

Due to the rapid growth of publications, librarians have been facing the problems caused by the shortage of stack as well as the quality deterioration of library collections. This naturally disappointed the user communities and the present library activities are weak and inadequate. It seems to the author that one of the desirable actions in remedying this problems is to weed library collections properly and regulraly. The purpose of this study is to establish weeding criteria in library collections, particulary in the fields of polictical science, economics and law In order to establish weeding criteria, shelf-time period which is the length of time that a book remains on the shelf between the last two users of a volume, was measured by examining the book cards or date-due slips of circulating books and collections which remained in the stack. The results of this study are as follows: (1) In the fields of political science economics and law, the shelf-time periods of general materials in Korean for circulation was measured. (2) This study shows shelf-time periods that vary in different subject fields. (3) Combining the shelf-time periods of books in active circulation and the total collection including books which have never been circulated, the size of library holdings which may satisfy a certain percentage of the current circulation can be estimated.

• 콘크리트학회논문집
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• 제17권6호
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• pp.1053-1064
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• 2005

The mechanical damage of concrete is normally attributed to the formation of microcracks and their propagation and coalescence into macroscopic cracks. This physical degradation is caused from progressive and hierarchical damage of the microstructure due to debonding and slip along bimaterial interfaces at the mesoscale. Their growth and coalescence leads to initiation of hairline discrete cracks at the mesoscale. Eventually, single or multiple major discrete cracks develop at the macroscale. In this paper, from this conceptual model of mechanical damage in concrete, the computational efforts were made in order to characterize physical cracks and how to quantify the damage of concrete materials within the laws of thermodynamics with the aid of interface element in traditional finite element methodology. One dimensional effective traction/jump constitutive interface law is introduced in order to accommodate the normal opening and tangential slips on the interfaces between different materials(adhesion) or similar materials(cohesion) in two and three dimensional problems. Mode I failure and mixed mode failure of various geometries and boundary conditions are discussed in the sense of crack propagation and their spent of fracture energy under monotonic displacement control.

• 한국세라믹학회지
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• 제43권9호
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• pp.519-526
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• 2006

A full-factorial design of experiments with three input factors and two levels for each factor including center points was utilized for the preparation and characterization of twelve types of $BaTiO_3$ slips for tape casting. Ceramic powders with different particle sizes, different milling methods such as high energy milling and conventional ball milling, and two types of dispersant with different polymeric species were chosen as input factors in order to investigate their effects on slip and on green tape properties. Tape casting, a small rectangular-shaped K-square preparation, characterization and quantitative data analysis using statistical software were followed. Ceramic powder was the most significant among three input factors for the output responses of slip viscosity and green tape density, showing more favorable results with large particles than with very fine ones. In addition, high energy milling for only 30 min was more efficient than 24h of conventional ball milling in terms of powder dispersion and milling. The optimum condition based on the experimental results was a slip exposed to high energy milling with large ceramic particles along with a methylethyl acetate dispersant.

• 대한기계학회논문집B
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• 제23권7호
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• pp.871-880
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• 1999

In this paper an experimental study is presented of the problem of dynamic behavior of a water droplet impinging upon a heated surface. The experiments are mainly focused on the effects of impinging angle of a droplet and surface temperature on the impact dynamics of the droplet. It Is clarified that the droplet exhibits much different behavior depending on the normal momentum of an impinging droplet before impact. At surface temperature In the nucleate boiling regime. the disintegration of a droplet doesn't occur, whereas the deforming droplet adheres to the surface. The spreading and contraction of the liquid film is repeated a couple of times for the horizontal surface but the expanded droplet just slips without noticeable contraction for the inclined surfaces. In the film boiling regime, the impinging droplet spreads over the surface as a liquid film which is separated from the surface by produced vapor. Depending on the magnitude of the normal momentum of the droplet the disintegration into the several irregular shapes of liquid elements occurs for the horizontal and 30o-inclined surfaces, whereas the impinging droplet for the 60o-inclined surface doesn't break up and tends to recover the original spherical shape.

• 대한인간공학회지
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• 제25권3호
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• pp.1-15
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• 2006

Loss of postural balance can possibly lead to increased risk of slips and falls in work places. Present study was performed to investigate the effects of noisy environments on postural stability during standing. It is known that a sound is characterized by the frequency and pressure level of the sound. Therefore, effects of the frequency and pressure level on postural stability were of primary concern. Ten male subjects participated in the experiment. Subject's center of pressure(COP) position was collected on a force plate while they were exposed to different frequency and pressure levels of the sound. Measured COP was then converted into the length of postural sway path in both anterior-posterior(AP) and medio-lateral(ML) axis. Results showed that the length of sway path in AP axis was significantly affected by the frequency of sound. The length of sway path was lowest at frequency level of 2000Hz and increased below and above this frequency range. The sound pressure level, however, did not significantly affect the postural sway length in both AP and ML axis. The results imply that industrial workers in noisy environments should be aware that their abilities of postural balance can be disturbed significantly.

• 전산구조공학
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• 제10권2호
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• pp.161-169
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• 1997

차량의 동적특성, 즉 소음, 진동, 승차감 및 조종안정성능 등에 중요한 영향을 미치는 부품중에 하나로 차체의 중량을 지지하고 노면과 접촉하여 회전하면서 조타성을 지니는 타이어를 고려하지 않을 수 없다. 지금까지의 이러한 타이어 최적설계에 이용되어지고 있는 예측기법으로는 유한요소해석 방법이 널리 활용되어 지고 있으나, 이는 타이어에 공기압 주입 및 차량의 조종안정성능이 우수한 타이어 제품개발 및 개선을 위해 차량 주행시 타이어와 노면과의 접지면에 작용하는 힘과 모멘트를 예측할 수 있는 유한요소해석 적용기법을 개발하였으며,이러한 해석기법을 통한 결과와 실측치는 매우 유사한 관계를 지니고 있음을 알 수 있었다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 Asia Navigation Conference
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• pp.115-120
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• 2006

The rail clamp is the device to prevent the crane slips along rails from the wind blast as well as to locate a container crane in the set position in operating mode. In this study we conduct the research for the sliding distance of rail clamp and the proper position of supporter with respect to the wedge angle in the wedge type rail clamp. The sliding distance to display the clamping force of the jaw pad corresponding to the design wind speed criteria is determined by the total displacement of the rail clamp at the roller center and the wedge angle. And the supporter is the device to prevent the overload which is applied on each part of the rail clamp by wind speed increment, because a clamping force is generated by the sliding of the wedge due to the wind. Accordingly the position of the supporter to prevent the overload is determined by analyzing the forces applied to the rail clamp. In order to analyze the sliding distance and the proper position of supporter with respect to the wedge angle as the wind speed is 40m/s, 5-kinds of wedge angles, such as 2, 4, 6, 8, $10^{\circ}$, were adopted as the design parameter.