• Journal of the Korean Society for Railway
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• v.10 no.3 s.40
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• pp.327-336
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• 2007

Operation a subway company requires high amount of early construction, operation and maintenance costs. Seoul Metro, one of the public subway companies in Seoul, Korea, has undergone operational deficit from its establishment, and the main reason is that the early construction and operation cost exceed the total revenue. Therefore, detailed researches on current operation system and possible alternatives are conducted to settle down finance trouble of the company. In particular, problems on operation and ticketing systems are analyzed, and based on that, necessity and detailed plan of railroad pass for one day are introduced and analyzed.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1221-1226
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• 2007

The subway with the initial constructive expense which is enormous together is the public transportation means where the many expense is expended in the operation and maintenance civil official. Seoul Metro until initial opening to traffic after present time cannot escape every year deficit to be, the cause is a possibility of seeking from the fare system which is short in transportation prime cost. Currently Seoul Metro is operating with the distance proportional fare system the passenger ticket system which is simple (usual volume, group volume and fixed amount volume, affection renunciation, charge free volume). When the biased characteristic of the user it plans considering from the goods development side for the variety for and a deficit solution, against the fare system systematic it researches and solution plan politically. Financial of the subway operation agency young the investigation against the present condition of the hazard subway fare system which is solved the bud with problem point a fare system from the research which it sees consequently and improvement program under analyzing the man with underdeveloped genital organ. Base on the reporter to analyze the introduction plan which with the character which will reach it follows with the necessity of introduction of the 1st passenger ticket (24 hour volume).

• Journal of Korea Water Resources Association
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• v.33 no.4
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• pp.447-459
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• 2000

Since the development of water resources is getting more difficult than ever before because of human-sociological condition, it would be necessary to develop a practically applicable technique for the management of water resources based on demand-side concept that could reduce unusable release for more effective and appropriate allocation of limited water resources. The objective of the study is to develop an optimal reservoir system operation model for water supply and energy augmentation by the combination of water budget analysis method in downstream area by MIP technique. The applicable study of the developed model was carried out and water supply capability of Nakdong river basin was re-evaluated by the developed model. The model has been found successful to guarantee appropriate water supply to the basin by means of deficit-supply management method and also turned out to be more practical tool for an optimal reservoir system operation model than other existing models.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.4
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• pp.113-119
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• 1991

In the present study, a methodology has been established for water budget analysis of a river basin for which monthyl rainfall and evaporation data are the only available hydrologic data. The monthly rainfall data were first converted into monthyl runoff data by an empirical formula from which long-term runoff data were generated by a stochastic generation mothod. Thomas-Fiering model. Based on the generated long-term data low flow frequency analysis was made for each of the oberved and generated data set, the low flow series of each data set being taken as the water supply for budget analysis. The water demands for various water utilization were projected according to the standard method and the net water consumption computed there of. With the runoff series of the driest year of each generated data set as an input water budget computation was made through the composite reservoirs comprised of small reserviors existing in the basin by deficit-supply method. The water deficit computed through the reservior operation study showed that the deficit radically increases as the return period of low flow becomes large. This indicates that the long-term runoff data generated by stochastic model are a necessity for a reliable water shortage forecasting to cope with the long-term water resourse planning of a river basin. F.E.M. program (ADINA) is also presented herein.

• Journal of the Korean Data and Information Science Society
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• v.18 no.1
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• pp.31-40
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• 2007

Many previous researchers tried to analysis relationship between financial index of hospitals such as revenue, expenses, and profit and hospital outcome such as number of inpatient and outpatient or, between that financial index and hospital size including number of hospital beds. However, these studies did not find exact relationship between financial index and hospital efficiency and productivity. Therefore, purpose of the study explores exact relationship between hospital financial outcome and hospital efficiency and productivity using adjusted inpatient days concept from American Hospital Association. Through the empirical analysis, the researchers find that hospital profit has the U-shape quadratic function to operation ratio. 66.9% of operation ratio is changing point and hospitals with 55.8% through 75.0% of operation ration have experience deficit situation. Considering the hospital circumstance, Korean hospitals would be to maintain general hospital type with various specialty departments.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.763-768
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• 2007

Korean railroad has been accomplished the structural change through separating of facilities and operation of railroad in 2004. The existent government organization was transformed into the public, this caused problem of renovation of railroad management. Korean railroad has been the integrated management of passenger and freight. As putting the passenger service as a priority, freight transportation have fallen behind and not attained good sales results. Restructuring in Korean railroad would bring about considerable improvement, but still not come out of the deficit operation. To find a way out of this situation, there needs to make renovation and extend new enterprise. However, to operate the railway freight transportation more competitively, make up situation that can possess competitive power fundamentally. From this perspective, the purpose of this study is to analyze the necessity for separated operation of passenger and freight railway transportation. By doing this can expect to obtain the competition power of railway freight transportation, and is a help to build up the independent management system of railway freight transportation and secure competitive high position about other transportation systems especially road.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.6
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• pp.482-487
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• 2004

Aims: This study was designed to determine the incidence of altered sensation in patients undergoing orthognathic surgery. Method: Seventy two patients who underwent orthognathic surgery between January, 1999 and December, 1999 constituted the study group. Seven patients were excluded because of lack of follow up. Sixty five patients were followed using objective and subjective neurologic testing during the period immediately following operation, 1 month, 2 months, 6 months, and 1 year postoperatively. Age ranged from 17 to 38 years, with a mean of 24.5 years. Male patients were 21, female 44. Twenty eight bilateral sagittal splitting ramus osteotomy(BSSRO) of mandible were performed, 35 BSSRO with genioplasty, 2 genioplasties. Information on the degree of intraoperative nerve encounter was obtained from the surgical reports in 47 patients and was divided into the following three categories: (1) the nerve was not encountered in 23 patients; (2) the nerve was exposed in 11 patients; (3) the nerve was exposed and repositioned from the proximal segment in 13 patients. Results: Four patients reported altered nerve sensation of lower lip and/or chin(6.2%) at final follow up. Two patients underwent BSSRO and the other two patients BSSRO with genioplasty. Three of the patients underwent nerve exposure during the operation. Conclusion: We suggest that the nerve exposure during the operation might be partly responsible for nerve dysfunction after orthognathic surgery.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.4
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• pp.126-131
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• 2012

In South Korea, there is no consideration for increasing labor costs and price fluctuation regarding the commission for a flight inspection. Because this causes a deficit in the flight inspection related operation, the cost system should be improved. Therefore, this research considers the first cost analysis in order to calculate a proper flight inspection commission through three different types of cost making methods. Moreover, as flight inspections are held by flights and human labors, labor costs are included as the main operation cost. According to the research, it is analyzed that the total cost to process flight inspection operations is decided by the scope of aircraft operation.

• 한국기계연구소 소보
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• s.14
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• pp.145-155
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• 1985

The recent trend in shipbuilding technology is toward development of highly economical vessels of which construction and operation costs are minimized, whereas cargo transport capacity is maximized. But, most of the vessel which are now operated by some of the nation's shipping companies are uneconomical ones built before oil crisis and consequently the companies are suffering from long-lasted deficit problem. In this paper, derivation study of optimum vessel for multi purpose cargo vessel on south-East Asian trade route is carried out to solve this problem. The Required Freight Rate is used as a measure of merits.

• Journal of The Korean Society of Agricultural Engineers
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• v.66 no.1
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• pp.25-37
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• 2024

As the agricultural land use shifts from paddy to upland, ensuring reservoir water supply stability for upland crop irrigation becomes essential. The objectives of this study were to estimate the irrigation water requirements considering the upland irrigation scenario and to evaluate the reliability of the water supply from the agricultural reservoir using resilience indexes. Two study sites, Sinheung and Hwajeong, were selected, and soybean and red peppers, the most water-intensive crops, were selected as study crops, respectively. For the irrigation scenario, two irrigation methods of traditional scheduling (which irrigates all sites at once) and rotational scheduling (which distributes irrigation by districts), along with the upland conversion rate, were considered. The net irrigation requirement was estimated through a water balance analysis. The stability of the reservoir was evaluated using resilience indexes based on the simulated 10-years reservoir water levels and drought criterion. Overall, the water supply of the reservoir was evaluated as stable during the simulated 10 years, except for the one year. Compared to the two irrigation methods, rotational scheduling resulted in lower irrigation water usage in both sites, with reductions of 1.6%, and 0.3%, respectively. As the upland conversion rate increases, the water deficit could be intensified in Hwajeong with a conversion rate exceeding 50%, showing the number of deficit(ND) over the one and a rapid increase in the deficit ratio(DR). It was confirmed that the reservoir operation criteria can be enhanced by incorporating resilience indicators along with crop growth information, thus, this will be a further study.