• Nuclear Engineering and Technology
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• v.17 no.4
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• pp.302-316
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• 1985

Small break LOCA caused by a stuck-open PORV is one of the important contributors to nuclear power plant risk. This paper deals with the design of a pressurizer surveillance system using microcomputer to prevent the malfunction of system and has assessed the effect of this improvement through Probabilistic Risk Assessment (PRA) method. Micro-computer diagnoses the malfunction of system by a process checking method and performs automatically backup action related to each malfunction. Owing to this improvement, we can correctly diagnose “Spurious Opening”, “Fail to Reclose” and “Small break LOCA” which are difficult for operator to diagnose quickly and correctly and reduce the probability of a human error by an automatic backup action.

• IEMEK Journal of Embedded Systems and Applications
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• v.6 no.6
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• pp.369-376
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• 2011

Since wireless sensor networks generally have the capability of network recovery, malfunction of a few sensor nodes in a sensor network does not cause a crucial problem paralyzing the sensor network. The malfunction of the sink node, however, is critical. If the sink node of a sensor network stops working, the data collected by sensor nodes cannot be delivered to the gateway because no other sensor nodes can take the place of the sink node. This paper proposes a TDMA-based wireless sensor network equipped with dual sink nodes, with a view to preventing data loss in the case of malfunction of a sink node. A secondary sink node, which synchronizes with a primary sink node and receives data from other sensor nodes in normal situations, takes the role of the primary sink node in the case of malfunction of the primary sink, thereby eliminating the possibility of data loss. The effectiveness of the proposed scheme is demonstrated through experiments.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.4
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• pp.65-71
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• 2006

The number of elevator installation increases every year about 15,000. The number of confine-disease of elevator increases every year and then sudden in, sudden stop, error of level indication, stand; those can bring to uneasiness of elevator passenger and malfunction related life accident is increasing. Therefore we researched elevator repair diary of elevator repairing company, APT management office and 119 life rescue for elevator confine-disease during 2004. 1. 1.${\sim}$12. 31. we analyzed the content and the time type and cause of the malfunction and fault for APT elevator. Form the result of 119 life rescue, only power reset is 24[%] and only power failure is 8.2[%] by cause of confine-disease. This paper will be used data of the analysis for mutual relation between Power Quality and malfunction and fault of elevator.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.3
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• pp.570-575
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• 2005

Malfunction by electrical surges is a serious problem on earth leakage current breakers(ELBs) used in a low voltage AC power system. In this paper, we tested ELBs according to IEC 61009-1 and KS C 4613 to analyze surge influence on ELB's malfunction. The test by application of surge voltage is specified both standards, but the test by application of surge current is specified only in IEC 61009-1. The experimental results showed that the ELBs used in this test are robust to surge voltage application, but the malfunction occurred to surge current application. Surge current is more frequent than surge voltage in actual situation. Therefore, ELBs should be tested by the surge current, and the domestic standard, KS C 4613, should includes a test procedure by the surge current application.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.10
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• pp.107-113
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• 2006

The number of confine-disease for elevator increases every year and then sudden stop, error of level indication stand; those can bring to uneasiness of elevator passenger and malfunction accidents related life accident are increasing. So we researched power quality counterplan equipment(SPD, Filter, Reactor) at site elevator controller room and malfunctions of elevator movement. We could confirm installation of power quality counterplan equipment recently and unchanging the number of malfunction. This data will be used the analysis for mutual relation between Power Quality(Sag, Interruption, ESD, ect.) and malfunction of elevator movement by testing the elevator equipment with EN12016(2004) and IEC standard level.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.9
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• pp.559-564
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• 2016

This study examined the malfunction mode of the HCMOS IC under narrow-band high-power electromagnetic wave. Magnetron is used to a narrow-band electromagnetic source. MFR (malfunction failure rate) was measured to investigate the HCMOS IC. In addition, we measured the resistance between specific pins of ICs, which are exposed and not exposed to the electromagnetic wave, respectively. As a test result of measurement, malfunction mode is shown in three steps. Flicker mode causing a flicker in LED connected to output pin of IC is dominant in more than 7.96 kV/m electric field. Self-reset mode causing a voltage drop to the input and output of IC during electromagnetic wave radiation is dominant in more than 9.1 kV/m electric field. Power-reset mode making a IC remained malfunction after electromagnetic radiation is dominant in more than 20.89 kV/m. As a measurement result of pin-to-pin resistance of IC, the differences between IC exposed to electromagnetic wave and normal IC were minor. However, the five in two hundred IC show a relatively low resistance. This is considered to be the result of the breakdown of pn junction when latch-up in CMOS occurred. Based on the results, the susceptibility of HCMOS IC can be applied to a basic database to IC protection and impact analysis of narrow-band high-power electromagnetic waves.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.27 no.2
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• pp.1-13
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• 2014

Objective : The purpose of this study is to understand conspicuous features of geroderma with visceral manifestation theory(臟象論). Methods : We categorized skin aging into wrinkles, hyperpigmentation, dry skin and face flush. After investigating the reason, histological changes and mechanism of each classification in western medicine, we interpreted them according to the malfunction of five viscera(五臟) in Korean medicine. Result : The results are as follows. 1. Pathologic change of dermis and subcutaneous fat makes wrinkles. We consider wrinkles as the malfunction of the spleen(脾). 2. Irregular synthesis and disproportion of melanin makes hyperpigmentation. We consider hyperpigmentation as the malfunction of the liver(肝). 3. Dry skin is attributed to a subtle disorder of epidermal maturation. We consider dry skin as the malfunction of the lung(肺). 4. Facial flush is detected in rosacea and menopausal hot flush, which are both related with blood vessel abnormality. We consider facial flush as the malfunction of the heart(心) Conclusion : We interpreted the pathologic changes and mechanism of skin aging in western medicine as the decrease of five viscera(五臟) in visceral manifestation theory(臟象論) of Korean medicine. Further studies are needed to apply these hypothesis to clinical diagnosis and treatment.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2025-2026
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• 2008

This study aims to analyze the features of malfunction of an SFC that helps maintain the frequency of static rotation during the operation of a gas turbine in power plants where power generators and controllers have such a complicated structure as a nerve system, by using electric interference with peripheral devices and maintaining acquired data efficiently. Also, in order to track the possibility of malfunction by various surges and noises which may occur in the process of inserting an SFC during the operation of a gas turbine and to prepare protective measures for the possibility, the study intends to offer data for developing a surge protector suited to the features of a section that is supposed to incur the possibility of malfunction.

• The Transactions of the Korean Institute of Power Electronics
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• v.19 no.4
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• pp.297-302
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• 2014

In this paper, a LED driver compatible with TRIAC-dimmer applying active bleeder is proposed. If TRIAC-dimmer is connected with LED driver, flicker phenomenon occurs by TRIAC malfunction. In order to prevent this problem, a current over holding current must flow into TRIAC. Therefore, additional circuit compatible with TRIAC-dimmer is required to provide enough current. Passive bleeder has power loss in whole operation period. The proposed circuit apply a valley-fill circuit for power-factor-correction and a novel active bleeder detecting malfunction point of TRIAC. Therefore, it prevent malfunction of TRIAC-dimmer and have advantage of higher efficiency than passive bleeder. To verify the validity of proposed circuit, 13W-lighting LED driver prototype has been proposed.

• Journal of IKEEE
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• v.19 no.3
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• pp.440-446
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• 2015

This study has examined susceptibility of LNA(Low Noise Amplifier) due to Front-Door Coupling under Narrow-Band high power electromagnetic wave. M/DFR(Malfunction/Destruction Failure Rate) was measured to investigate the diagnostic of IC test. In addition, decapsulation analysis was used to understand the inside of the chip state in LNA devices. The experiments is employed as an open-ended waveguide to study the destruction effects of LNA using a 2.45 GHz Magnetron as a high power electromagnetic wave. The susceptibility level of LNA was assessed by electric field strength, and its failure modes were observed. The malfunction of LNA device has showed as the type of self-reset and power-reset. The electric field strength of malfunction threshold is 524 V/m and 1150 V/m respectively. Also, he electric field of destruction threshold is 1530 V/m. Three types of damaged LNA were observed by decapsulation analysis: component, onchipwire, and bondwire destruction. Based on these results, the susceptibility of the LNA can be applied to a database to help elucidate the effects of microwaves on electronic equipment.