• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.2
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• pp.262-267
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• 2011

In the power system, the transformer's neutral earth reactor line 1 grounding failure may occur. By limiting the magnitude of the failure grounding current flow, it will aid to reduce the failure of the transformer. Consequently, this also may avoid the failure of the disconnection of the industrial insulator line that cause by melting. Besides, utilizing the decreasing circuit breaker or others related equipment can use to avoid the possibility of explosion of the transformer. If the failure happen during the operation of the power system, a huge interference will definitely may occur. Therefore, by installing the DONGBUSAN S/S #3M.Tr neutral earth reactor among TOP and BOTTOM BRACE part in the power system, the causes of the rising temperature and reason of the over-current flow that cause by over-current can be analyze.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.737-747
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• 2011

5678SMRT has installed various sensor for operating conditions(field of electric, facilities, signal, communication equipment and track) and environment of Every Function Room for remotely detecting and monitoring. Installed sound sensor for analyzed after remotely heard the noise of every equipment at Every Function Room and temperature sensor for check the temperature condition of Every Function Room. Additional installed voltage sensor in signal equipment room for monitoring RF track-circuit's voltage condition. Installed displacement sensor at The Chungdam bridge's railway for measuring and monitoring track displacement caused by temperature change and Pan/Tilt camera at sub-station and drainage for remotely field monitoring. Installed sensor for each equipment's operating condition and failure at Every Function Room then periodic check of workforce turned to around-the-clock surveillance by sensor therefore improvement of operating equipment. SMRT is lots of prevent a failure by Immediately detect of precondition of equipment failure by analyzed the sensor data. If the occurrence of an failure, become detected Immediately so possibility correct diagnosis and order by remotely field check by installed camera and sound sensor at field.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.1055-1058
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• 1988

A systematic way of failure diagnosis in a linear system with decentralized estimators is developed. The generalized likelihood ratio (G.L.R) approach to failure detection and identification is used for designing a diagnosis system in each subsystem based on the innovation analysis. For the simplicity of the theoretical formulation, a design scheme of failure diagnosis is developed for the system decomposed into two subsystems. To demonstrate the effectiveness of our approach, several simulation studies have been carried out on a third-order linear system which is constructed of a second-order damped oscillator and a first-order lag.

• Proceedings of the KWS Conference
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• 1996.10a
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• pp.19-34
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• 1996

A review was made of fatigue failures of nuclear power plant components in Japan, which were experienced in service and during periodical inspection. No case has been recently reported of a service fatigue failure of a reactor pressure vessel itself, excluding nozzle corner cracks, that occurred many years ago. But, service fatigue failures have been occasionally experienced in piping systems, pumps, and valves, on which fatigue design seems to have been inadequately applied. The causes of fatigue failures can be divided into two categories: mechanical-vibration-induced fatigue and thermal-fluctuation-induced fatigue. Vibration-induced fatigue failure occurs more frequently than is generally thought. The lesson gleaned from the present survey is a recognition that a service fatigue failure may occur due to any one or a combination of the following factors: (1) lack of communication between designers and fabrication engineers, (2) lack of knowledge about a possibility of fatigue failure and poor consideration about the effects of residual stresses, (3) lack of consideration on possible vibration in the design and fabrication stages, and (4) lack of fusion or poor penetration in a welded joint.

• Archives of design research
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• v.20 no.1 s.69
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• pp.133-142
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• 2007

Unlike face-to-face communication, text-based communication by digital media has limitations that non-verbal elements are eliminated and social presence decrease. To overcome this problem, people try to find solutions which visualize emotion and situation by using emoticons, icons, computer language and so on. As most SMS users experience the failure of using emotions on the mobile phone, they need to make up for this point. In this study, we conducted research on the recent mobile fonts situations and surveyed users' perception on SMS fonts as to suggest solutions of expressing and visualizing emotions on the mobile phone, a representative media of personal communication. As a solution of reducing the failure, we conducted a survey on users' perception about fonts and the capability of the expressing emotions by fonts. The survey found that mobile fonts can be used as a method to express human emotion. As a finding, the shape of the font can be used as a method to visualize the emotion through text messaging. In future studies, such a method can be applied to variety of different personal media with the communication method based on text. Those studies can propose different usage for fonts in communication.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.4
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• pp.188-195
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• 2020

Purpose: This study aimed to review the recent scientific literature regarding nursing care of arteriovenous fistula (AVF) for the patients with Chronic Renal Failure (CRF) undergoing hemodialysis. Methods: An integrative review was conducted and articles were searched from Cochrane library, Medline, PubMed, Science direct and CINAHL databases by using the terms "nursing", 'Chronic Renal Failure', 'Haemodialysis', renal failure', 'or 'AV Fistula' nursing care', 'self-care'. The inclusion criteria were articles published in English in the year of 2015-2020 with availability of free full text. Reviewed data were carefully analyzed and charted regard to the nursing care of the patient with AVF. Results: 12 articles papers met the inclusion criteria. Three themes were derived from the data: (a) Intervention (b). Patient and nurse education (c) KPA Assessment of (Knowledge, Practice and Attitude) Conclusions: This review indicates the challenges that nursing care of AVF patients undergoing hemodialysis. The identified themes can be used in the development of more effective educational- programs. Future studies should focus on the development and evaluation of educational programs that include these selected themes.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.10
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• pp.1079-1086
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• 2015

This paper introduces the architecture of OUTPUT module that is suitable using in safety related system having SIL4 and proposes the quantitative target that is required for OUTPUT module. Especially, only output type that is made up Relay output signal and analog signal among various output ways is applied in output module that is a part of safety related system. The FMEA(Failure Modes and Effect Analysis), FTA(Fault Tree Analysis) are used as analysis method. As a result, it proposes to the architecture and failure frequency of the Output module that is used in SIL4 safety related system.

• Journal of Communications and Networks
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• v.8 no.2
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• pp.228-233
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• 2006

Survivability is a very important requirement for the deployment of broadband networks because out of service links can affect volumes of traffic even if it is a very short time. And the data paths of broadband networks, which are critical for traffic engineering, are always necessary to be well protected. The procedure of protection or restoration for a path is initiated when failure is detected within the working path. In order to minimize the influence on transmission quality caused by the failure of links and to provide a definite time for the recovery from the failure, the protection switching time (PST) should be carefully considered in the path arrangement. Several researches have been devoted to construct the protection and restoration schemes of data paths over dense wavelength division multiplexing (DWDM) networks, however, there was rare research on the design of data paths with guaranteed protection switching time. In this paper, the PST-guaranteed scheme, which is based on the concept of short leap shared protection (SLSP), for the arrangement of data paths in DWDM networks is proposed. The proposed scheme provides an efficient procedure to determine a just-enough PST-guaranteed backup paths for a working path. In addition to selecting the PST-guaranteed path, the network cost is also considered in a heuristic manner. The experimental results demonstrate that the paths arranged by the proposed scheme can fully meet the desired PST and the required cost of the selected path is competitive with which of the shared path scheme.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.1
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• pp.261-268
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• 2017

The development of ICT technology centered on mobile smart platforms have been emerging as a shared economic platform based on collaborative consumption. In this study, we analyze what factors affect success and failure in commercialized shared economic platforms from 2008 to 2016, and present what policy factors are needed to activate shared economic platform. To do this, we analyze successful cases of shared economic platforms and failed cases, derive key variables that affect success and failure, and conduct inductive analysis based on ID 3 algorithm based on them. Through this, we present the policy factors for the commercial success of the shared economic platform by deriving the rules for the success and failure of the shared economic platform.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.169-177
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• 2021

Recently, the use of electric and electronic control systems is increasing in the automobile industry. This increase in the electric and electronic control system greatly increases the complexity of designing a vehicle, which leads to an increase in the malfunction of the system, and a safety problem due to the malfunction is becoming an issue. Based on IEC 61508 relating to the functional safety of electrical/electronic/programmable electronics, the ISO 26262 standard specific to the automotive sector was first established in 2011, and a revision was published in 2018. Malfunctions due to system failure are covered by ISO 26262, but ISO/PAS 21448 is proposed to deal with unintended malfunctions caused by changes in the surrounding environment. ISO 26262 sets out safety-related requirements for the entire life cycle. Functional safety analysis includes FTA (Fault Tree Analysis), FMEA (Failure Mode and Effect Analysis), and HAZOP (Hazard and Operability). These analysis have limitations in dealing with failures or errors caused by complex interrelationships because it is assumed that a failure or error affecting the risk occurs by a specific component. In order to overcome this limitation, it is necessary to apply the STPA (System Theoretic Process Analysis) technique.