• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2619-2627
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• 2009

The ground fault is occupying 70% among the total number of faults in ungrounded distribution power system. When the ground fault occurs in ungrounded system, the fault current is so small that it is hard to detect. But fault handling is very important because to continue power supply during fault conditions may cause the fault spreading and the distribution device in trouble. This paper presents the fault line detection method by using GPT signal detecting zero sequence voltage, and the fault section detection method by detecting whether GPT signal is disappeared or not during shifting normally open switch, which is connecting switch between distribution lines with open state in order to restore the outage area under emergency situation, and during isolating each section one by one which belongs to the fault line. This method is efficient because there is no whole power interruption during the fault section detection, and it is possible to perform both the fault section detection and the service restoration for the outage area at the same time, and it can apply to various distribution system configuration. Program for the fault restoration was developed applying proposed method, and it has been validated by applying to the pilot project of distribution automation system in Vietnam which has the ungrounded distribution system.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.6
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• pp.1-13
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• 2018

The number of deaths in Korea is higher than the OECD average. Therefore, an e-Call system is being developed as a vehicle ICT-based emergency rescue system that automatically detects an accident in the event of a vehicle accident and transmits related information to the center. In order to overcome the limitations of social acceptability and function of e-Call system, we propose a model that allows users to be aware of the necessity of service voluntarily. We predicted the market share of e-call services according to the proposed business model and analyzed it through B/C analysis. Benefits are calculated on a penetration basis, and device purchase and communications costs are calculated for each period. B/C analysis shows that pessimistic scenarios are 0.98 in 2025 and 1.01 in 2030. In an optimistic scenario, it is 1.05 in 2025 and 1.20 in 2030, which is more economical.

• Journal of Intelligence and Information Systems
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• v.22 no.1
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• pp.107-118
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• 2016

The advent of 5G mobile communications, which is expected in 2020, will provide many services such as Internet of Things (IoT) and vehicle-to-infra/vehicle/nomadic (V2X) communication. There are many requirements to realizing these services: reduced latency, high data rate and reliability, and real-time service. In particular, a high level of reliability and delay sensitivity with an increased data rate are very important for M2M, IoT, and Factory 4.0. Around the world, 5G standardization organizations have considered these services and grouped them to finally derive the technical requirements and service scenarios. The first scenario is broadcast services that use a high data rate for multiple cases of sporting events or emergencies. The second scenario is as support for e-Health, car reliability, etc.; the third scenario is related to VR games with delay sensitivity and real-time techniques. Recently, these groups have been forming agreements on the requirements for such scenarios and the target level. Various techniques are being studied to satisfy such requirements and are being discussed in the context of software-defined networking (SDN) as the next-generation network architecture. SDN is being used to standardize ONF and basically refers to a structure that separates signals for the control plane from the packets for the data plane. One of the best examples for low latency and high reliability is an intelligent traffic system (ITS) using V2X. Because a car passes a small cell of the 5G network very rapidly, the messages to be delivered in the event of an emergency have to be transported in a very short time. This is a typical example requiring high delay sensitivity. 5G has to support a high reliability and delay sensitivity requirements for V2X in the field of traffic control. For these reasons, V2X is a major application of critical delay. V2X (vehicle-to-infra/vehicle/nomadic) represents all types of communication methods applicable to road and vehicles. It refers to a connected or networked vehicle. V2X can be divided into three kinds of communications. First is the communication between a vehicle and infrastructure (vehicle-to-infrastructure; V2I). Second is the communication between a vehicle and another vehicle (vehicle-to-vehicle; V2V). Third is the communication between a vehicle and mobile equipment (vehicle-to-nomadic devices; V2N). This will be added in the future in various fields. Because the SDN structure is under consideration as the next-generation network architecture, the SDN architecture is significant. However, the centralized architecture of SDN can be considered as an unfavorable structure for delay-sensitive services because a centralized architecture is needed to communicate with many nodes and provide processing power. Therefore, in the case of emergency V2X communications, delay-related control functions require a tree supporting structure. For such a scenario, the architecture of the network processing the vehicle information is a major variable affecting delay. Because it is difficult to meet the desired level of delay sensitivity with a typical fully centralized SDN structure, research on the optimal size of an SDN for processing information is needed. This study examined the SDN architecture considering the V2X emergency delay requirements of a 5G network in the worst-case scenario and performed a system-level simulation on the speed of the car, radius, and cell tier to derive a range of cells for information transfer in SDN network. In the simulation, because 5G provides a sufficiently high data rate, the information for neighboring vehicle support to the car was assumed to be without errors. Furthermore, the 5G small cell was assumed to have a cell radius of 50-100 m, and the maximum speed of the vehicle was considered to be 30-200 km/h in order to examine the network architecture to minimize the delay.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.415-421
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• 2012

The purposes of this thesis are to grasp the aspect of injuries by violence which is the recent social issue, analyze the relationship with socioeconomic factors and provide it as the basic material of policy development and prevention. With the specimen in-depth investigation materials of injured patients of emergency room which is injuries examination system based on medical institution, this thesis compared injuries by violence with aspect of other injuries and conducted logistic regression analysis after controlling gender, age, educational level and occupation mutually. Women showed more danger to be exposed to injuries by violence than men. The less the age was, the more danger by violence was. The more academic background was, the less rate to be exposed to violence was. For occupations, there were dangerous in order of service workers, shop and market sales workers, unemployed, elementary occupations. In conclusion, Some differences of socioeconomic factors made an effect on the danger of injuries by violence victim.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.6
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• pp.55-61
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• 2008

In this paper, we proposed a multi-agent based healthcare system (MAHS) which is the combination of medical sensor module and wireless communication technology. This MAHS provides wide services to mobile telemedicine, patient monitoring, emergency management, doctor's diagnosis and prescription, patients and doctors, information exchange between hospital workers in a long distance. Also, MAHS is connected to Body Area Network (BAN) and a doctor and hospital workers. In addition, we designed and implemented extended JADE based MAHS that reduces hospital server's burden. Agents gather, integrate, and deliver the collected patient's information from sensor, and provide presentation in healthcare environment. Proposed MAHS has advantage that can handle urgent situation in the far away area from hospital like Islands through PDA and mobile device. In addition, by monitoring condition of patient (old man) in a real time base, it shortens time and expense and supports medical service efficiently.

• Korean Institute of Interior Design Journal
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• v.24 no.4
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• pp.23-32
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• 2015

This research tried identifying the current status of Gyongrodangs to find solutions to the problems of the oldest old through revitalization of the existing senior centers. With 31 national and public Gyungrodangs in Seocho-gu, Seoul as research subjects, the research contents include a survey of the facilities including main exit doors, living rooms and lounges, kitchens, and rest rooms in the Gyungrodangs by the checklist, and as the research tool a laser finder, measuring tapes, and cameras were used. The checklist was used as the research method to investigate main exit doors, living rooms and lounges, kitchens, and rest rooms. Based on the research results, the following conclusions are presented. The safety-related items of the public Gyungrodang facilities were reaching a critical level. They need to equip emergency exit routes, install exit lights and alarm bells, and teach how to use them. After that, the issue of rest room would be raised; the oldest old had difficulty in using the rest room with no consideration of universal design(UD), so installation of grab bars is needed around toilets, washstands, and urinals. Besides them, although absence of the western style furniture without consideration of users' ages caused inconvenience of using, there are no solutions due to the limited space. Unnecessary equipment such as treadmills which only occupy spaces without users should be thrown away and replaced with the furniture people would use like tables with supplement of furnitures to lie down and rest. Overall, the current Gyongrodang Facilities lack systems and need standardized management, in which the checklist this researcher developed and used in evaluating the present conditions could be recommended. It is expected that the evaluation system of senior centers would be arranged through this checklist, so that systematic service supply could be possible in the better facility environment.

• The Journal of Korean Academic Society of Nursing Education
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• v.24 no.2
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• pp.190-200
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• 2018

Purpose: The purpose of this study was to identify the level of perception of safety risk factors and the degree of performance of safety nursing activities in order to develop an education program to improve the safety of patients. Methods: The subjects were 217 nurses from 3 university hospitals in Incheon. Data were collected with structured questionnaires and analyzed using descriptive analysis, t-test, and ANOVA using SPSS 22.0. Results: The level of perception of patient's safety risk factors and safety care activities was 2.93 and 4.68, respectively. Perception of patient safety risk factors which belonging to the risk type of therapeutic devices, equipment, service and infrastructure all scored below average; also in addition, behavior, performance, and violence risk type and work system, information and communication risk type showed relatively low perception levels. Safety nursing activities showed a low level of performance in accurate communication among medical teams, management of fire and disaster, security management, use of restraints, identification of patients, and correct performance of operations and procedures. Conclusion: Based on these results, it is necessary to improve the safety of patients by taking proper management measures along with education.

• Journal of Industrial Convergence
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• v.17 no.4
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• pp.39-43
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• 2019

Mouse embryonic stem cell could show an substitutional materials of cells of neuron differentiation, positively increasing their effectiveness in the treatment of nervous symptom. We examined that mouse embryonic stem cells (mESCs) can be induced to undergo neuronal differentiation. After neuronal induction, the phenotype of mESCs changed towards neuronal morphology and mESCs were injected into the lateral ventricle of the experimental animal brain. Transplanted cells migrated to various parts of the brain and ischemic brain injury by middle cerebral artery occlusion (MCAO) increased their migration to the injured cortex. Intracerebral grafting of mESCs mostly improve sensory and motor nervous system of neurological injury in focal cerebral rats.

• Journal of Advanced Navigation Technology
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• v.15 no.4
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• pp.585-590
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• 2011

In the past few years, M2M (Machine-to-Machine) applications have become a hot topic in the wireless industry. While M2M applications can be used for many purposes (smart homes, smart metering/electricity meter reading, fleet management, mobile workforce, automobile insurance, vending machines, etc), and in many sectors (healthcare, agriculture, commercial, industrial, retail, utility, etc.), smart metering applications or smart grids present the biggest growth potential in the M2M market today. M2M platform is the future ubiquitous network technologies which provide the integrated service with the networks and devices. The promising technologies to tackle these problems are the Semantic technologies, for interoperability, and the Agent technologies for management of complex systems. In this paper the information communication technique based on the disaster prevention system's for the M2M, concepts and its requirement technology and application are studied.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.61-65
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• 2018

Our experiment studied that grafted stem cells reduced behavioral deficiency in rodent animal models of clip compressive surgery inducing spinal cord infarction. Our research proved the effect of embryonic stem cells to the spinal cord infarction caused by compressing T9-10 with an aneurysm clip, focusing the application of grafted stem cells for reduction of infarction and regeneration of spinal cord nervous injury. Therefore, our research suggests manifest results that implantation of mouse embryonic stem cell could show behavioral improvement after severe spinal cord damage. Therefore, mouse embryonic stem cell (mESC) could be useful application for the method in neurological injury. Conclusively, stem cell implant therapy may enhance the effectiveness of stem cell implant for central nervous system injury.