• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.2
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• pp.35-41
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• 2011

The national police agency has executed the project for the advancement of traffic control and operation systems in order to mitigate chronic traffic problems and to meet the global standards regarding the traffic control and operation systems. This study effort was initiated to evaluate the effects of various policies proposed for the advancement of traffic control and operation systems. The evaluation results indicated that the policies proposed for the advancement of traffic control and operation systems showed apparent and positive effects in terms of transportation mobility and safety. However, there have been many difficulties to overcome in order to settle down the policies proposed for the advancement of traffic control and operation systems as smooth as possible. For example, the violation of intersection passing method has been increased after the implementation of the advancement of traffic control and operation systems in majority of evaluation sites. In addition, lacks of awareness as well as improper operations of the advancement of traffic control and operation systems have caused drivers' confusions, which generated more traffic congestion and risks. Currently, the policies for the advancement of traffic control and operation systems focused on the improvements of traffic signal operations, including leading through movements and permissive left-turns. However, synergy effects may be expected if all of the policies including the improvements of traffic signal operations are executed together.

• Advances in pediatric surgery
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• v.13 no.1
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• pp.61-65
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• 2007

Conventional treatment of Hirschsprung's disease consists of initial colostomy followed by pull-through operation. But, the treatment of Hirschsprung's disease has been changed along with the development of new surgical technique. Since 1995, endo-GIA has been available at our hospital and one stage Duhamel operation has been performed for neonatal Hirschsprung's disease. Between May 1995 and April 2006, 26 neonates have been treated with one stage pull-through operation by one pediatric surgeon at HanYang University Hospital. The sex ratio was 4.2:1 with male predominance. Clinical findings included abdominal distension (96.2 %), vomiting (50.0 %), delayed passage of meconium (46.2 %), constipation (23.1 %), and enterocolitis (15.4 %). Twenty two cases (84.6 %) were short-segment and 4 cases (15.4 %) were long-segment disease, of which 2 cases were total colon aganglionosis. One of the two patients with total colonic aganglionosis had double transition zones - distal ileum and hepatic flexure of the colon. The average age at operation was $14.56{\pm}8.77$ days and the average weight at operation was $3.26{\pm}0.66kg$. Primary Duhamel operations were performed in 25 patients and Soave-Boley operations was performed in one patient. The endo-GIA 35 (Ethicon, USA) was used from 1995 until 1997, and after that endo-GIA 60 (USSC, USA) was used. The average Duhamel operation time was $88.57{\pm}22.80$ minutes. Wound abscess (n = 2) and septum formation (n =1) occurred after Duhamel operation. Bowel function was normalized in 59 % within 3 months and in 95% within 1 year after operation. There was no mortality after one stage pull-through operation in neonate.

• Journal of Industrial Technology
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• v.29 no.B
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• pp.221-228
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• 2009

For a stable supply of electric power, periodical inspection of the electric facilities and repair of the distribution lines are required. In case of any unexpected accidents, looped operation among distribution lines may be necessary in order to supply electricity through the sound lines, separating the faulted lines. As a result of this study, it was found that normal looped operation became impossible when phase difference of the looped distribution lines is more than 3 degrees compared with the voltage supply of the distribution lines. Therefore, for a stable supply of electric power to Chuncheon, it is judged to be desirable that looped operation of the distribution lines coming from the same substation M. Tr Bank shall be performed in principle and in case of looped operation with the substation of different system, looped operation among the lines shall be performed after voltage regulation of the substation M. Tr Bank, maintaining similar voltages and load supply volume in order to avoid phase difference through checking the operation conditions of each substation M. Tr Banks. And when looped operation among the distribution lines is scheduled, voltage regulation schedule has been established so far by calculating maximum supply volume through the transformer of the substation and the maximum load volume through the distribution lines but in the future, looped operation of the distribution lines shall be carried out by removing voltage difference with regulating tap or load of the surrounding transformers, with giving prior notice to the substation operators.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.113-120
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• 2013

This study aimed to obtain quantitative data for WWTP operators in phosphorus removal process. This was done by reviewing and comparing phosphorus removal efficiency(%), coagulants dosage(Al/P and $Al_2O_3$(mg/L)), sludge production($kg/m^3$), and operation cost($won/m^3$) of start-up and normal operation data. Phosphorus removal efficiency of all tertiary treatment process was up to 70 ~ 89 % in start-up and normal operation. Average molar ratio(Al/P) was similar as 5 in both operations, but average coagulants dosage (mg/L) of start-up (8.5 mg/L) was higher than normal operation (6.2 mg/L). Average operation cost was higher for start-up ($33.6won/m^3$) than normal operation ($28.4won/m^3$), while electricity cost required for the normal operation ($9.0won/m^3$) was higher by $3.5won/m^3$.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.185-196
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• 2012

Information system operation principles were recently established in order to provide high quality service and efficient operation audit of IT outsourcing. Operation managements are done based on these principles. Therefore, information operating management process, which refers to itself, is established. Information system operation audit requires a constant audit regularly, which is different from construction/development audit that is done only once. As operating management process changes, operation audit guidelines should be updated and improved. Therefore, this paper proposes IT outsourcing operation audit model with IT outsourcing achievement management as a focus. IT service domain was referred in order to propose information system operation audit model and check lists, which are based on IT outsourcing operation managements such as planning, making strategies, contract, service, and management. The deduced audit model and check lists verified suitability of the proposed model by experts' survey.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.3
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• pp.343-350
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• 2000

The goal of this study is the comparison of upper airway size and change of skeletal Class I group and skeletal Class III group (before operation, within 2 weeks after operation, 6 months after operation) respectively. At first, we measured the lines between selected upper air way landmarks on lateral cephalometric x-ray film of skeletal Class I 40 persons whoes age were 23-26 years old, ,and did the same lines of landmarks of skeletal Class III 44 persons who had not been operated yet, were within 2 weeks after operation, were 6 months after operation. And we compared it respectively and analyzed it with paired t-test. We studied the relationship of those on produced data. 1. Skeletal Class III group was narrower in nasopharyngeal air way space than that of skeletal Class I group, and increased in thickness of oropharyngeal, hypopharyngeal wall within 2 weeks after operation, and reduced in nasopharyngeal, oropharyngeal air way space, and did in thickness of nasopharngeal, hypopharyngeal wall 6 months after operation. 2. Skeletal Class III group reduced in nasopharyngeal, oropharyngeal air way space, and increased in thickness of nasopharyngeal, oropharyngeal, hypopharyngeal wall within 2 weeks after operation, restored the thickness of nasopharyngeal, oropharyngeal wall, but did not restored nasopharyngeal, oropharyngeal, hypopharyngeal air way space. 3. Vertical length from hyoid bone to mandibular plane did not have signifacant difference from Class I group but after operation, it increased more than Class I group significantly. 4. The size of airway reduced after operation. Among this, oropharyngeal airway most reduced.

• Journal of Information Technology Services
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• v.18 no.4
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• pp.67-82
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• 2019

The purpose of this study is to improve the calculation method of the software operation pricing proposed by the software business price calculation guide from 'input manpower method' to 'rate calculation method'. The software operation pricing of the input manpower method is not objectively calculated in the domestic IT outsourcing situation where the statistical data based on the activity based estimating is insufficient and it is decided by agreement between the owner and the client. In addition, there was no standard for adjusting the productivity according to the characteristics of the operation service. In order to improve this, an operational correction factor item that can affect the software operation productivity was selected based on foreign and domestic standards, and it was confirmed through the first questionnaire to IT operation managers. In order to determine the level of difficulty of the fixed operational correction factors, the operational correction factor using AHP technique was confirmed through a second questionnaire for pairwise comparison. The operational difficulty calculation table was developed with reference to COCOMO and ITIL standards. Finally, we propose a new pricing scheme that reflects the operating rate. Regression analysis was carried out by collecting the data of the domestic public institutions on the estimated cost and the actual cost calculated from the new rate method software operation pricing. The results of the regression analysis show that the estimated cost and the actual cost are related to each other. Mean magnitude of relative error(MMRE) and PRED[25] analysis were added for accuracy analysis. MMRE and PRED also showed satisfactory results, confirming the possibility of replacing the rate method software operation pricing.

• Journal of Korea Water Resources Association
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• v.37 no.10
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• pp.837-844
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• 2004

In this study, the efficient reservoir operation is studied by comparing results from reservoir operation using a basin drought forecasting and warning system with an existing reservoir operation rule. As a result, it is found that the reliability and average annual storage of reservoir operation using a basin drought forecasting and warning system and release coefficients is better than those of reservoir operation using the existing operation rule. The release coefficients for Yongdam dam located in the Geum river basin selected as a case study are found to be the most effective for the value of 0.95 for the drought watch, 0.9 for the drought warning and 0.85 for the drought emergency. The reservoir operation using a drought forecasting and warning enables the use of the limited water resources effectively during drought and will contribute the national water resources management.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.217-225
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• 2005

Because of the limitation of controllable operation variables for the wastewater treatment process with variable hydrodynamic flow patterns, it may preclude the use of this type of nutrient removal activated sludge process. As the operation variables, only temperature and dissolved oxygen (DO) have been used to operate the process. This study made an effort to improve treatment efficiency and operability of the process by the following methodologies: 1) process and operation data analysis using process simulation, 2) determination of optimal control logic or algorithm using a pilot-scaled experimental apparatus and its operations, and 3) application of experimental and simulation results to find the optimal process operation modes. In this study, it was found that the optimal operation mode named 'save mode' in the basis of process variables, such as the ammonia-nitrogen concentration of inlet flow, temperature and flow rate, can reduce the operation cost comparing with the present normal operation mode. And the stable conditions in nitrification were also shown by the proportional control of DO with the inlet air flow rate of blower and the mixing rate of mechanical aeration.

• Journal of Korean Society for Quality Management
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• v.46 no.4
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• pp.899-910
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• 2018

Purpose: Generally, since the population density is lower in suburban areas, the distance to school is inevitably long. Therefore, schools in suburban areas often operate school buses to improve student welfare. However, since school buses are usually used only during going to and from school, the utilization rates are relatively low. Therefore, this study aims to establish integrated operation plan of public school bus covering all schools. Methods: It is necessary to decide which school buses will serve the specific demand node which want to go to certain school in order to design an integrated operation plan for school buses. Therefore, a mathematical model is developed for minimizing the total number of vehicles and the distance of transportation by reflecting the characteristics of school buses and students as constraints. To solve the proposed mathematical model, CPLEX, a commercial solver, is applied. Results: To validate and to confirm the proposed process, numerical example is designed with the comparison between before and after integrated operations of school buses in terms of total operation cost. The result shows that the integrated operation can lead the reduction of the number of school buses as well as the decreasing of the fuel cost. Conclusion: This study provides the quantitative method to perform the integrated operation of school buses in suburban areas. The optimal operation strategy is required because there are more complex decision-making elements considering the integrated operation. It is expected to apply this research result at real situation to expand this services based on an optimal operation.