• Journal of Navigation and Port Research
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• v.38 no.4
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• pp.373-378
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• 2014

In order to prepare for recapitalization of differential GNSS (DGNSS) reference station and integrity monitor (RSIM) due to GNSS diversification, this paper focuses on differential correction algorithm using GPS/Galileo pesudorange. The technical standards on operation and broadcast of DGNSS RSIM are described as operation of differential GPS (DGPS) RSIM for conversion of DGNSS RSIM. Usually, in order to get the differential corrections of GNSS pesudorange, the system must know the real positions of satellites and user. Therefore, for calculating the position of Galileo satellites correctly, using the equation for calculating the SV position in Galileo ICD (Interface Control Document), it estimates the SV position based on Ephemeris data obtained from user receiver, and calculates the clock offset of satellite and user receiver, system time offset between GPS and Galileo, then determines the pseudorange corrections of GPS/Galileo. Based on a platform for performance verification connected with GPS/Galileo integrated signal simulator, it compared the PRC (pseudorange correction) errors of GPS and Galileo, analyzed the position errors of DGPS, DGalileo, and DGPS/DGalileo respectively. The proposed method was evaluated according to PRC errors and position accuracy at the simulation platform. When using the DGPS/DGalileo corrections, this paper could confirm that the results met the performance requirements of the RTCM.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.672-682
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• 2020

The Korea Nowadays, which is research on digital twin technology for efficient operation in various industrial/manufacturing sites, is being actively conducted, and gradual depletion of fossil fuels and environmental pollution issues require new renewable/eco-friendly power generation methods, such as wave power plants. In wave power generation, however, which generates electricity from the energy of waves, it is very important to understand and predict the amount of power generation and operational efficiency factors, such as breakdown, because these are closely related by wave energy with high variability. Therefore, it is necessary to derive a meaningful correlation between highly volatile data, such as wave height data and sensor data in an oscillating water column (OWC) chamber. Secondly, the methodological study, which can predict the desired information, should be conducted by learning the prediction situation with the extracted data based on the derived correlation. This study designed a workflow-based training model using a machine learning framework to predict the pressure of the OWC. In addition, the validity of the pressure prediction analysis was verified through a verification and evaluation dataset using an IoT sensor data to enable smart operation and maintenance with the digital twin of the wave generation system.

• The Journal of Korean Academic Society of Nursing Education
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• v.4 no.1
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• pp.66-80
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• 1998

With the opening of healthcare market, the health care environment in Korea is anticipating a drastic change. In this Internationally open market environment, it is necessary to introduce a systematic health care plan and DRG system which offer qualitative medical services as well as reduced cost. Purpose of this study is to develop and test the critical pathway for Cesarean section patient in the way to be possible the integrated inpatient management. It was adopted the process of six phases to develop the critical pathway as the theoretical framework implemented by Johns Hopkins Hospital, Maryland, U.S.A. In the first phase, make a selection of diagnosis/procedures to develop. In the second phase, organize a development team consisted of eight expertises working in maternity nursing area. In the third phase, analyze the overall medical service offered to patient through review medical records and decided the service content and the implementation period for the Cesarean section patient. In the forth phase, make out a preliminary critical pathway after verification of expert group on content validity. In the fifth phase, validity operate to ten Cesarean section patients to test implementation in practice by using the preliminary critical pathway, In the sixth phase, defined the final critical pathway. The result of this study was as follows. 1. There were classified 8 categories as monitoring/assesment, treatment, medication, activity, diet, test, consult, education/discharge plan for vertical axis and showed hospital stayed from admission to discharge for horizontal axis of critical pathway through analysis 68 Cesarean section patients medical records. 2. After critical review 68 medical records to make out a preliminary critical pathway, hospital stays for horizontal axis were showed 6 days, mean hospital stays were 7.5 days, 2.1 days were to be taken operation after admission and 4.2 days were stayed until discharge after operation. 3. After making out a questionare in 90 items of a medical service content of eight categories and verifying the content validity of expertises, the 85 items of the preliminary critical pathway were selected by expertises agreement over 88% and modified or deleted 5 items showing agreement below 75%. 4. After verifying a validity to 10 patients for 4 weeks, hospital stays were 5.9 days. There were deleted 1 item and modified or supplemented the 9 items of the 10 items.

• Journal of the Korean Arthroscopy Society
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• v.7 no.1
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• pp.81-86
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• 2003

Purpose : The clinical consequences of arthroscopic Bankart repair using suture anchor with non-absorbable suture as well as various factors, expected to have an effect on the prognosis of disease, have been evaluated and compared through preoperative and postoperative modified Rowe score. Materials and Methods : Twenty-eight cases were evaluated for the subject of this study, which enabled us to follow up at least for more than 18 months from lune, 1997 to May, 2001. Modified Rowe score was used for the evaluation of preoperative and follow-up shoulder function and stability. After setting up 9 factors expected to affect a prognosis, a statistical verification was conducted. Results : The postoperative Rowe score was 87.3, while preoperative Rowe score was 28.4 and the Rowe score was improved significantly(p=0.000). There were 1 case of redislocation and 2 cases of limitation of motion in the shoulder. In prognostic factor analysis through Rowe scoring system. Rowe score of their age at a trauma under 20 years was greater than that of above 20 years and it was significant(p=0.023). Conclusion : It was thought that arthroscopic Bankart repair using suture anchor was one or useful treatment method for recurrent shoulder dislocation patients. It was considered that their age at initial trauma was the factor to affect a prognosis.

• Journal of Distribution Science
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• v.16 no.7
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• pp.67-75
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• 2018

Purpose - In the 21st century, as information technology advances alongside the emergence of the 4th generation, industrial age, industrial environment has become individualized and customized. It is important to hire good quality employees for good service in the industry. The e-learning market is growing every year. Although e-learning companies are finding better quality employees in e-learning, it is not easy to find it. Companies also spend a lot of time and cost to find employee. On the employees side, they want to get a job freely when they want, but they cannot find their job easily. Furthermore, the labor market environment is changing fast. In the 4th generation, industrial age, employers require to find manpower whenever they need and want at little cost. So of their own accord, we have considered the necessity of management of human resources for employees and employers in e-learning. The purpose of this study is to propose a human cloud platform framework for enabling an efficient management of human resources in e-learning industry. Research design, data, and methodology - To pinpoint the items of a human cloud platform framework, the study was initiated according to the following process. First, items of competency relating to e-learning instructional designer was analyzed. Second, based on the items of information from this analysis, selection and validity verification took place with 5 e-learning specialists group. Third, the opinion of experts who were in charge of hiring in e-learning companies were collated with the questionnaire. Lastly, the human cloud platform framework was proposed based on opinion results. Results - The framework was comprised of 7 domains and 27 items in order to develop the human cloud platform for e-learning instructional designer. The analysis results showed that the most highly considered item were 'skill (4.60)' that employee already have the capability. Following this (in order) were 'project type (4.56)', 'work competency (4.56)', and 'strength area of instructional design (4.52)'. Conclusions - The 27 items in the human cloud platform framework were suggested in this study. Following this, we can consider to develop the human cloud platform for finding a job and hiring e-learning instructional designer easily. For successful platform operation, we need to consider reliability between employer and employee. In addition, we need quality assurance system based on operation has public confidence.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.4
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• pp.180-188
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• 2017

Recently, as the strength of winds and waves increases due to the climate change, abnormal waves such as swells have been also increased, which results in the increase of downtime events of loading/unloading in a harbour. To reduce the downtime events, breakwaters were constructed in a harbour to improve the tranquility. However, it is also important and useful for efficient port operation by predicting accurately and also quickly the downtime events when the harbour operation is in a limiting condition. In this study, numerical simulations were carried out to calculate the wave conditions based on the forecasted wind data in offshore area/outside harbour and also the long-term observation was carried out to obtain the wave data in a harbour. A forecasting method was designed using an auto-regressive (AR) and artificial neural networks (ANN) models in order to establish the relationship between the wave conditions calculated by wave model (SWAN) in offshore area and observed ones in a harbour. To evaluate the applicability of the proposed method, this method was applied to predict wave heights in a harbour and to forecast the downtime events in Pohang New Harbour with highly complex topography were compared. From the verification study, it was observed that the ANN model was more accurate than the AR model.

• Journal of Convergence for Information Technology
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• v.8 no.4
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• pp.237-245
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• 2018

The purpose of this study is to suggest the improvement plan for an effective benefit sharing support policy through empirical analysis on the benefit sharing operation of government as well as the benefit sharing support policy of government affecting firm performance. Therefore, this study analyzed current problems on benefit sharing operation of government as well as performed a survey for 225 participating and cooperation firms regarding firm performance. This study found some improvements such as insufficient diverse incentive measures leading to the difficulty of participating firm's increase and spread, insufficient substantial benefit sharing such a cash allocation between consignment firms, the increase of biz management system model failing to induce innovation of new technology or product, and difficult spread into 2nd, 3rd cooperative firms besides 1st ones, meanwhile, verifying the positive influence of government benefit sharing support policy on both participating and cooperation firms, especially on the performance of cooperation firms. As a further study, it is necessary to increase the objectiveness and accuracy of a research through verification of the interrelationships between firm statue and performance on the basis of more objective and quantitative data such a sales increase or R&D capability of cooperation firms.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1147-1159
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• 2018

This study focuses on the verification of a rapid protection automation system using an inflatable structure. The inflatable structure is an automatic rapid protection system against human and material damage when the subsea tunnel is flooded. Especially, it is essential for construction and operation of subsea tunnels. In this study, we have experimentally verified the rapid protection automation system using the inflatable structure designed for this problem. In order to verify this, a model tunnel with a 40: 1 reduction ratio was constructed, and air pressure of 0.1 bar and 0.15 bar was injected to divide the tunnel according to the expansion rate at 10 sec and 20 sec. According to the results of the study, the protection efficiency was better at 0.15 bar than 0.1 bar when the expansion structure was expanded, and the protection efficiency and influent control efficiency were different according to the pneumatic injection time of the inflating structure. As a result of this study, it was found that the higher the internal air pressure of the inflated structure and the faster the inflation of rate, the more effectively the inflated structure was inflated. As a result of this study, it is necessary to further study the wedge type structure which is useful for the storage method of expansion structure, shape and expansion derivative, inhibition of expansion structure during protection and control of inflow water.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.2
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• pp.187-192
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• 2019

Hybrid power storage system with emergency power function for demand management and power outage minimizes the investment cost in the building of buildings and factories requiring emergency power generation facilities, We propose a new business model by developing technology that can secure economical efficiency by reducing power cost at all times. Normally, system power is supplied to load through STS (Static Transfer Switch), and PCS is connected to system in parallel to perform demand management. In order to efficiently operate the electric power through demand forecasting, the EMS issues a charge / discharge command to the ESS as a PMS (Power Management System), and the PMS transmits the command to the PCS controller to operate the system. During the power outage, the STS is rapidly disengaged from the system, and the PCS becomes an independent power supply and can supply constant voltage / constant frequency power to the load side. Therefore, it is possible to secure reliability through verification of actual system linkage and independent operation performance of hybrid ESS, By enabling low-carbon green growth technology to operate in conjunction with an efficient grid, it is possible to improve irregular power quality and contribute to peak load by generating renewable energy through ESS linkage. In addition, the ESS is replacing the frequency follow-up reserve, which is currently under the charge of coal-fired power generation, and thus it is anticipated that the operation cost of the LNG generator with high fuel cost can be reduced.

• Food Engineering Progress
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• v.21 no.4
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• pp.312-317
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• 2017

Weight loss that influences quality and farmer incomes is affected by the storage environment of agricultural products. The interior of storage should be maintained at high humidity to prevent the weight loss of products which contain a lot of moisture. The research had constantly proceeded with change in the heat exchanger surface areas, humidity systems, and weight loss forecast to maintain high humidity within storage. Relative humidity that exerts an effect weight loss of crop is influenced by storage temperature, leak state, and volume of product. When weight loss is predicted, different conditions of these factors are derived. In case of CA storage, ways of forecasting the weight loss become easier compared to cold storage due to sealed storage with external environment during storage period. In this study, apples were stored in purge-type CA storage and weight loss has been predicted by using operating characteristics and environmental conditions. As a result, humidity variation in the storage fluctuates with the operation of the unit-cooler. Furthermore, unit-cooler operation factor is influenced by outside temperature and respiration heat. Prediction value of weight loss according to temperature and humidity has been most accurately predicted. Prediction value through defrosting water measured shows unit-cooler work quality. K-value needs verification to calculate the VPD method.