• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.6214-6220
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• 2015

A track circuit has used stably more than 100 years for detecting train position, but solution of track circuit sort circuit incapacity due to a rust is necessary for side line in station yard, coast line and level crossing for conventional line in rural line. Domestically, Axle Counter System(ACS) has partially used for Hot Box System for high speed line and turnout for CBTC system. In contrast, most of countries has used ACS not only trunk line but also rural line and its application has increased for metro, electric car and industrial railway. In this paper, we has verified the operating status of ACS which installed with existing track circuit through log analsis to implement pilot application in mail track and turnout in station yard. And interface test with interlocking system has conducted at Obong shunting yard, as well as Cheongju station and has analyzed test result. Based on a test result, we made fail safe design, manufacturing skill and established system requirement specification for the smooth operation and maintenance.

• Journal of Soil and Groundwater Environment
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• v.13 no.4
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• pp.22-29
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• 2008

To understand environmental characteristics and contamination assessment of the Namsan Park soil in Seoul, we divided the Namsan map into 33 sectors and sampled mixed soil in depth 0${\sim}$15 cm, in 5${\sim}$10 points at the sites. We analyzed soil samples collected at 21 sectors twice on May and September. The results were as follows. The hue color ranges of the Namsan soil were 2.5YR${\sim}$10YR, the value ranges were 1${\sim}$4, the water rates were 3.1${\sim}$22.3 and the Ignition losses were 3.4${\sim}$10.4%. The average concentration of Cu and Pb were determined 3.374 and 15.000 mg/kg, Cd and As showed very low level. The mean concentrations of Zn and Ni were showed 103.290 and 11.649 mg/kg and this amount is not different from the nationalwide mean in 2005. The mean pH showed 5.41. The Zn, Ni and Cd in the soil of the circular road of Namsan showed 1.33, 1.48, 1.46 times higher than the other sector of the Namsan soil. The corelation coefficient between water rate and ignition loss were 0.720 and the correlation coefficient between Cu and Pb, Cu and Zn showed 0.827, 0.694 respectively. There was weak corelationship between pH and Zn. The Uniformity coefficient (Uc) of all the survey sites was determined below 5 in the range of 1.5${\sim}$4.4.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1254-1268
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• 2009

In 1998, because of the economic crisis called IMF Crisis in Korea, Kyungbu high speed railway project could run by modifying the original plan to open it as a 1st phase only by utilizing the existing railway lines from Seoul to Siheung and the other one from Daegu to Pusan. The modified plan includes that the line from Daegu to Pusan will be constructed as a second phase in next time. Starting railway operation with the changed plan, the combined application operation of high speed rail, passenger rail and freight rail was caused partly from Seoul to Siheung to run into capital area. As a result, the opinion for additional railway line construction is insisted continuously because the operation volume of passenger rail was forced to be reduced, the service quality of it was decreased and it became difficult to add new high speed services. Moreover, with regard to Honam high speed rail, the new construction plan of station in Kangnam metro area as a basement station for starting from Suseo was changed to the plan of turning out at Osong because of the economic effectiveness and this kept resident people in Kangnam metro area and southern Kyungki area unable to get the opportunity of high speed rail service benefit. After beginning of Kyungbu high speed railway operation, national transportation system developments are focused on high speed rail, and when the second phase construction of Kyungbu high speed rail, beginning operation of Kyungjeon line, Jeolla line double track construction, Honam high speed rail in 2014, is completed, the demand for high speed rail will be increased and it is unavoidable to make Kwangmyung station as a basement station and to reduce the number of passenger rail operation. At this moment, it is valuable to consider adding the railway line capacity in capital area to improve the transferring service for citizen who live in area without Kyungbu high speed rail station and to expand the service area from Kangbuk to Kangnam and southern Kyungki area. Accordingly, in this paper, the effective rail operation method, facility plan and the other issue to be reviewed for increasing capital high speed railway lines will be mentioned.

• Pediatric Infection and Vaccine
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• v.8 no.1
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• pp.101-106
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• 2001

Purpose : The outbreaks of measles in infants and school children have been reported recently, but there are no specific treatment of these patients except symptomatic therapy. This study was performed to evaluate the effectiveness of intravenous gammaglobulin(IVGG) therapy in acute febrile phase of measles. Methods : The 68 cases in measles were treated with single dose of IVGG(400~500 mg/kg), and 44 cases were treated with only symptomatic treatment during the periods of 14 months from Jan. 2000 to Feb. 2001. They were compared to duration of fever, rash, the levels of CRP and days of admission on both groups after treatment. Results : The results obtained follows. The average of age was $7.9{\pm}3.6$ year old, and male to female was 1.0 : 1.6. The duration of fever after admission was $2.4{\pm}1.2$ days in treated group and $5.7{\pm}2.4$ days in control group. The period of disappearance of systemic erythematous maculopapular rash was $4.5{\pm}1.3$ days in treated group, and $6.9{\pm}2.4$ days in control group. The durations of admission day were also shown significantly shorter duration of period in treated group(P<0.05). The levels of CRP were no significant difference between two groups before treatment. However, treated group was significantly shown by improved within 5 days after IVGG therapy(P<0.05). Conclusions : The single dose of IVGG(400~500 mg/kg) therapy is one of rapid and effective therapy for clinical symptoms and signs in acute high febrile phase of measles.

• Composites Research
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• v.17 no.2
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• pp.41-48
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• 2004

"Phenolic composite", one of safety composites was chosen to build rolling stock in England while it was applied to building materials in London Underground facilities. This paper was written by Mr. Denver E. Brown. He emphasizes, from visibility and toxicity points of view, phenolic is the best and Mr. Forsdyke says, there is no question, passenger's lives are No. 1 issue, material recycling is not No.1! not No.1!

• Journal of the Korean Society for Railway
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• v.12 no.3
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• pp.405-411
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• 2009

Railway signaling system in a rapid transit using the ATC system the approved a speed limit to a train and a part of signaling system in a metro approved a distance which is possible to move. Referring to the way of transmitting train control information, there are the one transmitting it to the on-board system of a train using the direct track, the another transmitting it establishing an instrument, and the other transmitting an instrument by a railway track. The one is the method using the direct track as a conductor for composing the part of the track and attaining the information controlling a train by transmitting a signal to the track. It is used for the high-speed railway and the subway. The method using the track attains information by transmitting it to returned information, and the on-board system of a train attains it by magnetic coupling. Because many reinforcing bars on the concrete slab track are used, interaction between a rail and a reinforcing bar that is not produced on ballast track is made. Due to the interaction, the electric characteristic of rail is changed. In the current paper, we numerically computed the coupling coefficient between the rail and the reinforcing bar based on the concrete slab track throughout the model related to the rail and the reinforcing bar using the concrete slab track that is used in the second interval of the Gyeongbu high-speed railway, and we defined the coupling coefficient not changed in the electric characteristic of rail in the condition that there is no interaction between the rail and the reinforcing bar.

• The Korean Journal of Health Service Management
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• v.2 no.1
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• pp.56-83
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• 2008

The purpose of this study was to provide basic materials needed to enhance quality of organizational life by identifying the improvements of labor union management in the perspective of general hospital organization management. The subject of this study were 686 employees in 12 General Hospitals in Metro Capital including Seoul. Materials were collected from administrators, nurses and medical technicians in target hospitals from March 20 to May 10, 2005 through survey questionnaires. The main results of this study were as follows: 1. the commitment level of the subjects according to their characteristics was higher in older employees than the younger ones, large family to support than small family to support and those who had higher positions in labor union. 2. The commitment level of the subjects according to the job and role related variables were higher those who had higher satisfaction level to their job and manager, role conflict in all hospitals. 3. The commitment level of the subjects according to union related variables, variables jointly controlled by union and employer was satistically significant positive correlation. In other words, the commitment level of the subjects according to the subjects' labor union involvement was higher in those who had higher satisfaction in labor union and perceived their colleagues' attitudes more positively in all hospitals. Regarding the atmosphere of the relationship between union and employer and the level of commitment in labor union, the better the atmosphere of the relationship between union and employer was, the higher the level of commitment in labor union was in all hospitals. 4. The results of multiple regression analysis shows that formal and informal socialization, union participation to the union management cooperation program, job satisfaction, satisfaction with the labor union's were all found as important antecedents of labor union commitment. 5. Job and role-related variables, union-related variables, variables jointly controlled by union and employer, and labor union commitment level were all found significantly different in accordance with the characteristics of unions concerned. To summarize study results, the level of commitment in labor union depends on job satisfaction, manager's attitudes, satisfaction to their jobs, union satisfaction, their colleagues attitudes toward union and the atmosphere of employer-employee relationship. Therefore hospital managers should have democratic and flexible attitudes toward labor union. Additionally, as formal and informal socialization, union participation to the union-management cooperation program is important determinant in union commitment, hospital managers should have countermeasures to enhance the colleague attitude and job satisfaction level of hospital employees. Since this study deals with psychological nature of workers not a few drawbacks and shortcomings may be detected in the finding. Nevertheless, the finding of this study, to become a momentum that will stimulate further research to detect all the cues of labor union commitment and to provide valuable reference in forming logical union commitment and labor union-management cooperation.

• Health Policy and Management
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• v.30 no.3
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• pp.326-334
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• 2020

Background: Korea has gradually expanded the coverage of medical care services in its national health insurance system. On April 1, 2018, it implemented a policy that expanded the coverage for an ultrasonography in the upper abdomen. In this study, we aimed to investigate the effect of the policy on the utilization of the ultrasonography in the upper abdomen in tertiary care hospitals. Methods: Using the dataset of the Health Insurance Review and Assessment Service, we explored changes in the utilization of the ultrasonography in the upper abdomen in tertiary care hospitals from July 1, 2017 to November 30, 2018 through the difference-in-difference (DID) mixed-effects-model method. Facility factor, equipment factor and personnel factors, type of hospital, the total amount of medical care expenses, and geographic region were considered as control variables. Results: On average, the utilization of the ultrasonography in the upper abdomen increased by 228% after the coverage expansion policy. However, the results of DID mixed-effects-model method analysis showed that the utilization increased by 73%. As for the number of beds, the utilization was higher with a group of 844-930, 931-1,217, and 1,218 or greater compared with a group of 843 or fewer, while the utilization of the number of ultrasonic devices was lower with a group of 45-49 compared with a group of 44 or fewer. The utilization decreased with the number of interns and the number of nurse assistants. Besides, relative to Seoul, the utilization was lower in the other metro-cities and provinces. Conclusion: The coverage expansion policy in the national health insurance system increased service utilization among people. Future research needs to investigate the degree to which such coverage expansion policy reduces the unmet medical care needs among the deprived in Korea.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.515-524
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• 2022

The turnout system of the sleeper floating tracks (STEDEF) on urban transit is a Anti-vibration track composed of a wooden sleeper embedded in a concrete bed and a sleeper resilience pad under the sleeper. Therefore, deterioration and changes in spring stiffness of the sleeper resilience pad could be cause changes in sleeper support conditions. The damage amount of manganese crossings that occurred during the current service period of about 21 years was investigated to be about 17% of the total amount of crossings, and it was analyzed that the damage amount increased after 15 years of use (accumulated passing tonnage of about 550 million tons). In this study, parameter analysis (wheel position, sleeper support condition, and dynamic wheel load) was performed using a three-dimensional numerical model that simulated real manganese crossing and wheel profile, to analyze the damage type and cause of manganese crossing that occurred in the actual field. As a result of this study, when the voided sleeper occurred in the sleeper around the nose, the stress generated in the crossing nose exceeded the yield strength according to the dynamic wheel load considering the design track impact factor. In addition, the analysis results were evaluated to be in good agreement with the location of damage that occurred in the actual field. Therefore, in order to minimize the damage of the manganese crossing, it is necessary to keep the sleeper support condition around the nose part constant. In addition, by considering the uniformity of the boundary conditions under the sleepers, it was analyzed that it would be advantageous to to replace the sleeper resilience pad together when replacing the damaged manganese crossing.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.669-675
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• 2020

In this study, 3D analysis was compared in evaluating the track deformation of subway structures during adjacent excavation. For the 3D analysis model, the boundary conditions of the tunnel model and the application level of the ground water were analyzed as variables. As the result of the effects of track irregularity using the 3D model, the analysis model considering the site ground water level instead of the design values and changing the constraint of the boundary condition is more reasonable. In addition, the influence of track irregularity due to the boundary condition and load condition of the analytical model is more obvious in the factors directly affected by the longitudinal relative displacement of the rail, such as alignment, cross level and gauge irregularity. Therefore, the evaluation on track stability according to adjacent excavation work was appropriate to analysed the longitudinal deformation of the track by using 3D model that could be investigate the deformation of rail. In addition, the boundary condition and load condition(ground water level) of the numerical model was important for accurate analysis results.