• Journal of the Ergonomics Society of Korea
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• v.23 no.4
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• pp.1-8
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• 2004

The objective of this study is to identify the effects of material position and physical fatigue on postural stability. Ten male subjects participated in this study. After bicycling exercises, their centers of pressure (COPs) were measured under four material handling positions and four excercise levels. The measured COPs were then utilized to calculate postural sway length in each experimental condition. Subjects' postural stability was quantified using the sway length. Results showed that the effect of different material handling position was significant on the postural sway length in both the posterior-anterior axis and the medio-lateral axis. Results also showed that the postural sway length was increased as physical fatigue accumulated, significantly in subject's posterior-anterior axis. The results imply that bearing a material on the back or front with both hands appeared to cause least sway length and instability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.97-100
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• 1994

The present paper is devoted to the physical and electrical characteristics of N-docosyl- quinolinium-TCNQ films compared with the films doped with I$_2$. Iodine affects the degree of charge transfer and the conductivity of the films. The UV-visible absorption spectra of the film doped with I$_2$ shows that the peak of I$_3$ which had electronic transition at 300∼350nm and (TCNQ-)$_2$ dimer absorption disappered. The in-plane electrical conductivity of the films doped with I$_2$ were 1.4${\times}$10$\sub$-6/S/cm, which is two orders of magnitude higher conductivity than undoped LB films. The film structural difference between Y and Z-type may cause the conductivity. Another possible reasons of the structural difference was the overlapping TCNQ anion radical in LB films.

• Journal of Korean Orthopaedic Sports Medicine
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• v.2 no.2
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• pp.113-118
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• 2003

Throwing motion divided by 6 phases such as wind-up, (early and late) cocking, acceleration, deceleration, follow-through. Overuse injuries in baseball result most often from pitching. Poor mechanics is the leading cause of arm injuries. The purpose of this article is to analyze the each joint motion and evaluate the biomechanics and pathomechanics during pitching.

• Journal of Trauma and Injury
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• v.26 no.4
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• pp.319-322
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• 2013

A 66 year-old woman had cervical spinal cord injury by an automobile. We performed emergency operation for partial quadriplegia. She recovered from motor weakness gradually, but complained of abdominal distension and mild dyspnea. A physical examination of her abdomen did not have tenderness and rebound tenderness. She underwent a decubitus view of chest X-ray due to aggravated dyspnea at postoperative 4 days. We detected free air gas of abdomen and immediately identified a cause of pneumoperitoneum by abdominal computed tomography. We performed an emergent laparotomy and confirmed a jejunal perforation. After an operation, she recovered well and is under rehabilitation.

• Tribology and Lubricants
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• v.18 no.2
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• pp.127-132
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• 2002

The Taguchi method, a robust experimental design, was used to optimize manufacturing parameters of a brake lining during hot pressing and heat treatment. A friction material containing 15 ingredients was employed fur this experiment and friction and wear tests were carried out by using a pad-on-disk type tribotester. Sixteen brake linings with different manufacturing conditions were examined according to a parameter design. From the results of the signal-to-noise (S/N) ratio and the analysis of variance (ANOVA), the cause and effect of the manufacturing parameters on physical properties (hardness and porosity) and friction and wear characteristics of brake linings was obtained.

• Korean Journal of Human Ecology
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• v.8 no.3
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• pp.453-464
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• 1999

Child abuse can cause children to sustain various damages including physical, mental, psychological, behaviour damages, and etc., and damages thereof have long term effects as well as short term effects. Because of its serious negative consequences, punishment of child abuser and prevention measures are necessary. It was for this reason that we decided to produce this work which would define child abuse by examining existing studies of child abuse cases in Korea and would suggest prevention measures by analysing current situation.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1533-1535
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• 1994

The Monte-Carlo simulation was used to define the physical mechanisms of the initiation phase of pseudo-spark discharge. The pseudo-spark discharge employing the hollow cathode geometry is accompanied by very fast current rising and intense charged particle beams. In this model, time-dependent continuity equation for the electrons and ions were solved consistently with Poisson's equation for the electric field in a two-dimensional, sysmmetrically cylinderical geometry. From the simulation, a sequence of physical mechanisms that cause the rapid current rise associated with the onset of pseudo-spark discharge mode were identified.

• Journal of KIISE:Software and Applications
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• v.26 no.1
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• pp.80-80
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• 1999

As Temporal DataBase Systems(TDBSs) manages both the historical versions and the current version of each data item, a temporal transaction may access more data records than atransaction in traditional database systems. Hence, the concurrency control subsystem of temporaldatabase management system should be able to correctly and efficiently detect actual conflicts amongconcurrent temporal transactions while the cost of detecting conflicts is maintained in low levelwithout detecting false conflicts which cause severe degradation of system throughput.In this paper, Two-Level Conflict Detection(TLCD) scheme is proposed for efficient conflictdetection between concurrent temporal transactions in TDBs. In the proposed TLCD scheme, sincechecking conflict between concurrent temporal transactions is performed at two levels, i, e., logicallevel and physical level, conflicts between concurrent temporal transactions are efficiently and correctlydetected,Furthermore, we also evaluate the performance of the proposed TLCD scheme with those oftraditional conflict detection schemes, logical-level conflict detection scheme and physical-level conflictdetection scheme by simulation approach, The result of the simulation study shows that the proposedTLCD scheme outperforms the previous conflict detection schemes with respect to the averageresponse time.

• The Journal of Fisheries Business Administration
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• v.18 no.2
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• pp.53-67
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• 1987

In the fish industry, the perishabiliy of raw material, saeasonality of catch and diatance between production and consumption combine to cause physical distribution to be a difficult decision problem. In fishery physical distribution, the choice of appropriate landing port is a major problem. This paper deals with transshipment model to determine landing port as intermediate transfer point and the market to which fish should be sent. Transshipment model is useful to determine intermediate transfer point and can be reformulated as LP model. So this study developes transshipment model for korea large trawler ana analized the model output. It can be expended to a realistic problem in order to provide information to port planner and decision maker on the trade-offs between the cost and efficiency of fishery transportation.

• Structural Engineering and Mechanics
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• v.32 no.2
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• pp.321-335
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• 2009

When a roof frame is subjected to the airblast loading, the conventional way to analyze the damage of the frame or design the frame is to use single degree of freedom (SDOF) model. Although a roof frame consists of beams and girders, a typical SDOF analysis can be conducted only separately for each component. Thus, the rigid body motion of beams by deflections of supporting girders can not be easily considered. Neglecting the beam-girder interaction in the SDOF analysis may cause serious inaccuracies in the response values in both Pressure-Impulse curve (P-I) and Charge Weight-Standoff Diagrams (CWSD). In this paper, an inelastic two degrees of freedom (TDOF) model is developed, based on force equilibrium equations, to consider beam-girder interaction, and to assess if the modified SDOF analysis can be a reasonable design approach.