• Journal of ILASS-Korea
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• v.8 no.1
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• pp.9-15
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• 2003

The liquid phase LPG injection (LPLI) system is considered as one of the next generation fuel supply systems for LPG, vehicles, since it can accomplish the higher power, higher efficiency, and lower emission characteristics than the existing mixer type fuel supply system. However, during the injection of liquid LPG fuel into the inlet duct of an engine, a large quantity of heat is extracted due to evaporation of fuel. A problem is that the moisture in the air freezes around the outlet of a nozzle, which is called icing Phenomenon. It may cause damage to the outlet nozzle of an injector. The frozen ice deposit detached from the nozzle also may cause a considerable damage to the inlet valve or valve seat. In this work, the experimental investigation of the icing phenomenon was carried out. The results showed that the icing phenomenon and process were mainly affected by humidity of inlet air instead of the air temperature in the inlet duct. Also, it was observed that the icing occurs first in the inlet of a nozzle, and grows considerably at the upper part of the nozzle inlet and the opposite side of the nozzle entrance. An LPG fuel, mainly consisting of butane, has lower latent heat of vaporization than that of propane, which is an advantage in controlling the icing phenomenon.

• 한국터널공학회:학술대회논문집
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• 2005.04a
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• pp.270-281
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• 2005

An especial attention for old tunnel safety is required on increasing of The various tunnel recently. Specially, the lining investigation method of the old tunnel will be able to presume condition of concrete lining indirectly. Because it is many restriction thought of environment and ground condition investigation method of tunnel lining rear. This study carried out section & convergence measurement of part which was deformed in tunnel lining. It had been observed for the change of tunnel behavior with a continuous measurement. It has been analyzed for a cause of tunnel deformation and inspected for the effect after a repair-reinforcement to tunnel compared with the effect before those by structure analysis. By establishing automatic measurement system after repair-reinforcement to tunnel, it would be accomplished to convergence measurement continually. As a result, it was observed that deflection and deformation of tunnel was convergent. but it should be followed to a continuous maintenance because of unstable ground condition, cause of inner tunnel, environment. The railroad tunnel which was executed a reinforcement of the tunnel lining must investigate the close condition of reinforcement lining and concrete lining.

• Journal of Wellbeing Management and Applied Psychology
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• v.7 no.1
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• pp.27-33
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• 2024

Purpose: This study investigates human error accidents in the Korean railway sector, emphasizing the need for systematic management to prevent such incidents, which can have fatal consequences, especially in driving-related jobs. Research design, data and methodology: This paper analyzed data from the Aviation and Railway Accident Investigation Board and the Korea Transportation Safety Authority, examining 240 human error accidents that occurred over the last five years (2018-2022). The analysis focused on accidents in the driving, facility, electric, and control fields. Results: The findings indicate that the majority of human error accidents stem from negligence in confirmation checks, issues with work methods, and oversight in facility maintenance. In the driving field, errors such as signal check neglect and braking failures are prevalent, while in the facility and electric fields, the main issues are maintenance delays and neglect of safety measures. Conclusions: The paper concludes that human error accidents are complex and multifaceted, often resulting from a high workload on engineers and systemic issues within the railway system. Future research should delve into the causal relationships of these accidents and develop targeted prevention strategies through improved work processes, education, and training.

• Clinical and Experimental Pediatrics
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• v.61 no.11
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• pp.366-370
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• 2018

Purpose: Tuberculosis (TB) is one of the most important diseases that cause significant mortality and morbidity in young children. Data on TB transmission from an infected child are limited. Herein, we report a case of disseminated TB in a child and conducted a contact investigation among exposed individuals. Methods: A 4-year-old child without Bacille Calmette-$Gu{\acute{e}}rin$ vaccination was diagnosed as having culture-proven disseminated TB. The child initially presented with symptoms of inflammatory bowel disease, and nosocomial and kindergarten exposures were reported. The exposed individuals to the index case were divided into 3 groups, namely household, nosocomial, or kindergarten contacts. Evaluation was performed following the Korean guidelines for TB. Kindergarten contacts were further divided into close or casual contacts. Chest radiography and tuberculin skin test or interferon-gamma-releasing assay were performed for the contacts. Results: We examined 327 individuals (3 household, 10 nosocomial, and 314 kindergarten contacts), of whom 18 (5.5%), the brother of the index patient, and 17 kindergarten children were diagnosed as having latent TB infection (LTBI). LTBI diagnosis was more frequent in the children who had close kindergarten contact with the index case (17.1% vs. 4.4%, P=0.007). None of the cases had active TB. Conclusion: This is the first reported case of TB transmission among young children from a pediatric patient with disseminated TB in Korea. TB should be emphasized as a possible cause of chronic diarrhea and failure to thrive in children. A national TB control policy has been actively applied to identify Korean children with LTBI.

• Journal of Society of Preventive Korean Medicine
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• v.12 no.2
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• pp.185-195
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• 2008

The purpose of this investigation is comparing two groups one applied with taping therapy the other with controlled causes variation in pain substances of blood ${\beta}$-endorphin, serotonin with taping therapy. 12 male students of S college divided into two groups each 6 experimental and controlled with no history of flexion and extention of lower extremity focused on knee joint. Experimental group applied with elastic taping before experiment at quadriceps, calf muscles, hamstrings and tibialis anterior, controlled group didn't applied any taping therapy. Bruce protocol of maximal progressive loading exercise implemented 5 minutes after blood samples were extracted. And 5 minutes after the exercise blood samples also were taken and made investigation. Data before and after investigation were operated on SPSS Ver. 12.0 for Window(Kor.). P value 0.05. The affirmative effects of this investigation was proved with increased ${\beta}$-endorphin and decreased serotonin that cause reducing pain.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.3
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• pp.3-10
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• 2019

On November 15, 2017, an earthquake($M_L5.4$) occurred in Pohang. Pohang earthquake was the second largest earthquake since earthquake was observed in Korea, but structural damage caused by earthquake was biggest. Structural damage caused by Pohang earthquake was mainly caused by schools and pilotis, above all damage to pilotis was outstanding. This is because area where pilotis structures are concentrated is located near epicenter, and seismic performance of pilotis structures is not excellent compared with general structures. In this study, described results of damage investigation and analysis of damage causes through analysis of pilotis Structures on 131 buildings that were investigated immediately after Pohang earthquake. In addition, cause of damage was analyzed through analysis of seismic wave. Investigation site was selected to Jangseong-dong, where damage occurred in large numbers. Damage level was classified into A, B, and C level by measuring residual crack width and story drift of structural members.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.9 no.1
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• pp.114-128
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• 1996

"Chimumchang" seems to be a kind eczema. The cause and symptom of eczema is similar to that of chimumchang. so, I investigated the literatures of oriental medicin and recent medicine. The results are summarized as follows. 1. Chimumchang seems to be a kind of eczema. Allergic contact dermatitis, atopic dermatitis, seborrheic dermatits, neurodermatitis, nummular dermatitis, xerotic eczema and so on are similar to chimumchang on cause & symptom. 2. The cause of chimumchang are summer vital energy excess(夏脈太過), sehwa excess(歲火太過), herat meridian wind-heat(心經風熱), heart fire(心火), wind taken spleen dampnees(脾濕受風), and so on. The cause of eczema are contact of external agent, immunological problem, heridity, infection, abnormalities of sebaceous glands, neurologic dysfuction, and so on. 3. The symptoms of chimumchang have been described to the three pattern on literature of oriental medicine until now. 1) scratching slightly, It has exudation, and combination. 2) Vital energy on skin is irritable by psychological problem. At the acute stage the patient is complain of itching & pain, and gradually the exudation expands in whole body. 3) early peorid it's size is very small, and at first the patient is complain of itching, later complain of pain. The exudation change to ulcer and expands in the whole body. 4. In the investigation of prescription(Total: 34, Oral medicine: 4, Ointment: 30), the most frequently used oral medicine is sungmatang(4 times), and the most frequently used ointment are kohosan, korvunsan and kegwanhyuldobang.

• Journal of the Korea Safety Management & Science
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• v.26 no.2
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• pp.1-10
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• 2024

Human stampedes were a major hazard that could occur during mass gatherings, but they have received limited attention in korea. However, after the 10.29 Itaewon disaster, this atmosphere has turned around. The cause of such an accident and how to prevent it should be considered. The main aim of this study is to identify the reason why did the accident happen at that time, the root cause, and the triggering cause with Delphi-AHP survey method. In addition, various preventive measures were investigated by experts to prevent accidents similar to 10.29 Itaewon disaster. Problems and solutions were presented by collecting expert opinions on the causes and preventive measures of the 10.29 Itaewon disaster. However, the opinion of the experienced peoples who experienced the risk at the Itaewon was not included, so further investigation is considered necessary.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.3
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• pp.142-148
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• 2004

Recently, with the growth of software for electromagnetic-thermal analysis, it has been studied that the precise analysis and investigation for cause of the electrical fire using computer simulation is on the basis of theroy for electromagnetic-thermal analysis. But it is very lacking for the precise analysis and investigation of cause for the electrical fire. In this paper, we have simulated the temperature distribution of wire to current and the force between the two conductors according to the current and the distance of the vinyl flat-type electrical wire(600 V, VFF, $2C{\times}$1.25mm^2) using the finite element method(Flux2D) in a overcurrent. And we will present the cause analysis method of electrical fire by experiment for distance between the two conductors according to current and time using large current supply device(Model: EHT_EFAD, Korea) in a overcurrent.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09c
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• pp.3-10
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• 2010

Case study was carried out on the interpretation of the mechanical behavior of a severely damaged reinforced earth wall comprising geotextile with the concrete panel facing. In this part I, the outline of the damaged reinforced earth wall is in detail described. The background and cause of the damage are discussed based on the results of site investigation. The engineering properties of the fill were examined by performing various in-situ and laboratory tests, including the surface wave survey (SWS), PS-logging, RI-logging, soaking test, the direct shear box (DSB) test, bender element (BE) test, etc. The background as well as the cause for the damage of the wall may be described such that i) a considerable amount of settlement took place over a 3m thick weak soil layer in the lower part of the reinforced earth due to seepage of rainfall water, ii) the weight of the upper fill was partially supported by the geo-textile hooked on the concrete panels (n.b., named conveniently "hammock state" in this paper), and iii) the concrete panels to form the hammock were severely damaged by the unexpectedly large downwards compression force triggered by the tension force of the geotextile. The numerical simulation for the hammock state of the wall, together with counter-measures to re- stabilize the wall is subsequently described in Part II.