• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1360-1363
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• 1996

EPD(End Point Detection) is used to decide etching degree of layer which must be removed at wafer etching process in plasma etching process which is one of the most important process in semiconductor manufacturing. In this thesis, the method which detects malfunction of etching process in real-time will be discussed. Several EPD signal traces are collected in normal plasma etching condition and used as reference EPD signal traces. Critical points can be detected by applying differentiation and zero-crossing techniques to reference EPD signal. Mean and standard deviation of critical parameters which is memorized from reference EPD signal are calculated and these determine the lower and higher limit of control chart. And by applying statical control chart to EPD signals which are collected in real etching process malfunctions of process are detected in real-time. By means of applying this method to the real etching process we prove our method can accurately detect the malfunction of etching process and can compensate disadvantage of current industrial method.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.233-238
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• 2002

This paper propose the construction of fault diagnosis engine for diesel generator engine and rule inference method to induce rule for fuzzy inference from the monitored data of diesel engine. The proposed fault diagnosis system is constructed the Malfunction Diagnosis Engine(MDE) and Hierarchy of Malfunction Hypotheses(HME), It is Proposed the rule reduction method of knowledge base for concerning data among the various analog data.

• Journal of Electrical Engineering and Technology
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• v.11 no.3
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• pp.775-780
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• 2016

This induced voltage measurement test and electromagnetic field simulation are related to the possibility of control signal malfunction by power line. Through an experiment, this research analyzed whether the voltage causing control malfunction according to the on/off status of power permitted to power line was induced to control signal line. Also, the research calculated the voltage induced to control signal line and examined the phenomenon by conducting an electro-magnetic field-specific simulation through the finite element method for the cable model used in the experiment.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.139-144
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• 2003

This study was aimed to establish failure management plan of the rubber-tired AGT light rail vehicle for its safety case, which was developed according to the Korean standardized specifications for the light rail vehicle. Vehicular 9 failure modes anticipated during the system operation were considered, which are single malfunction of redundant equipment, malfunction of train radio, public address and air compressor, battery, main circuit NFB trip, on-board ATO control device malfunction, on-board ATP control device malfunction, fail of brake release, flat tire, train emergency door open.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.2
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• pp.87-93
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• 2005

Recently, nuisance tripping or malfunction of MCCB(Melded Case Circuit Breaker) and ELB(Electrical Leakage Breaker) is being increased according as load circuits and equipments of electrical customers are various and complicated, but investigation of actual conditions on malfunction of MCCB and ELB was not implemented This paper investigated causes and influences of malfunction of MCCB and ELB by making up a question to electrical safety managers of two hundred and eighteen private electrical facilities. The results show that users above $70[\%]$ experienced malfunction of MCCB and ELB, and causes of malfunction are in order aging(above $25(\%)$), nuisance tripping $(above\;22(\%))$, goods badness$(above\;20(\%))$, abnormal power like as harmonics$(above\;20(\%))$ and others $(about\;9(\%))$. Also, second damages due to failure of MCCB and ELB are in order goods production, equipment trouble, information loss, business and operation interrupt, and others. The results of this study can be used in making decisions regarding causes of MCCB and ELB trip.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.11 no.6
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• pp.96-103
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• 1997

This paper deals with the malfunction characteristics of the earth leakage circuit breakers(ELBs) applied by a lightning impulse voltage. In the cases of the regulation of KS C 4613 and the simulated circuits with surge protection devices, the dead operation characteristics of the ELBs against lightning impulse voltages were experimentally investigated and discussed. As a result, all the specimens(ELBs) used in this work have a cutoff performance of the lightning impulse voltage when the differential mode surges were injected at the input terminals of the ELBs owing to a surge absorber installed at the power source side of amplification circuit. Four kinds of the specimens have brought about malfunction in the condition of the lightning impulse dead operation test defined in KS C 4613, and the malfunction voltages are relatively high and are about 5-6.5[kV]. In the case of the simulated test circuit with surge protection devicesthree kinds of the ELBs have led to malfunction. Also the voltage level causing the malfunction of the ELBs is decreased by operation of surge protection devices, and it ranges from 3 to 5(kV).

• Journal of Korean Neurosurgical Society
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• v.66 no.2
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• pp.162-171
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• 2023

Objective : The goal of this study was to analyze the clinical outcomes of endoscopic third ventriculostomy (ETV) and endoscopic septostomy when shunt malfunction occurs in a patient who has previously undergone placement of a ventriculoperitoneal shunt. Methods : From 2001 to 2020 at Seoul National University Children's Hospital, patients who underwent ETV or endoscopic septostomy for shunt malfunction were retrospectively analyzed. Initial diagnosis (etiology of hydrocephalus), age at first shunt insertion, age at endoscopic procedure, magnetic resonance or computed tomography image, subsequent shunting data, and follow-up period were included. Results : Thirty-six patients were included in this retrospective study. Twenty-nine patients, 18 males and 11 females, with shunt malfunction underwent ETV. At the time of shunting, the age ranged from 1 day to 15.4 years (mean, 2.4 years). The mean age at the time of ETV was 13.1 years (range, 0.7 to 29.6 years). Nineteen patients remained shunt revision free. The 5-year shunt revision-free survival rate was 69% (95% confidence interval [CI], 0.54-0.88). Seven patients, three males and four females, with shunt malfunction underwent endoscopic septostomy. At the time of shunting, the age ranged from 0.2 to 12 years (mean, 3.9 years). The mean age at the time of endoscopic septostomy was 11.9 years (range, 0.5 to 29.5 years). Four patients remained free of shunt revision or addition. The 5-year shunt revision-free survival rate was 57% (95% CI, 0.3-1.0). There were no complications associated with the endoscopic procedures. Conclusion : The results of our study demonstrate that ETV or endoscopic septostomy can be effective and safe in patients with shunt malfunction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.652-661
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• 2020

Recently, the Korean government developed the RE3020 (renewable energy) policy to overcome environmental problems, such as fine dust, climate change, and large-scale PV systems interconnected with a distribution system. When a large-scale PV system is interconnected in the distribution system, however, a malfunction can occur, and the protection devices may not be operated because of the dividing effect depending on the magnitude and direction of fault current as well as connection types and location of the PV system. Therefore, this paper proposes a search algorithm for the malfunction pattern of protection devices based on various scenarios, when large-scale PV systems are operated and interconnected in a distribution system. This paper presents a malfunction mechanism of protection devices according to the installation locations of recloser (R/C). Furthermore, the modeling of a distribution system with large-scale PV systems was performed using Off-DAS S/W, and the malfunction patterns of protection devices were analyzed based on a range of scenarios. From the simulation results with the proposed model and algorithm for searching for protection devices, it was confirmed that they are useful and effective in identifying a malfunction phenomenon depending on the installation location of the R/C and connection type of PV system.

• Journal of Korean Neurosurgical Society
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• v.60 no.1
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• pp.1-7
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• 2017

Objective : The diagnosis of shunt malfunction can be challenging since neuroimaging results are not always correlated with clinical outcomes. The purpose of this study was to evaluate the efficacy of a simple, minimally invasive cerebrospinal fluid (CSF) lumbar tapping test that predicts shunt under-drainage in hydrocephalus patients. Methods : We retrospectively reviewed the clinical and radiological features of 48 patients who underwent routine CSF lumbar tapping after ventriculoperitoneal shunt (VPS) operation using a programmable shunting device. We compared shunt valve opening pressure and CSF lumbar tapping pressure to check under-drainage. Results : The mean pressure difference between valve opening pressure and CSF lumbar tapping pressure of all patients were $2.21{\pm}24.57mmH_2O$. The frequency of CSF lumbar tapping was $2.06{\pm}1.26times$. Eighty five times lumbar tapping of 41 patients showed that their VPS function was normal which was consistent with clinical improvement and decreased ventricle size on computed tomography scan. The mean pressure difference in these patients was $-3.69{\pm}19.20mmH_2O$. The mean frequency of CSF lumbar tapping was $2.07{\pm}1.25times$. Fourteen cases of 10 patients revealed suspected VPS malfunction which were consistent with radiological results and clinical symptoms, defined as changes in ventricle size and no clinical improvement. The mean pressure difference was $38.07{\pm}23.58mmH_2O$. The mean frequency of CSF lumbar tapping was $1.44{\pm}1.01times$. Pressure difference greater than $35mmH_2O$ was shown in 2.35% of the normal VPS function group (2 of 85) whereas it was shown in 64.29% of the suspected VPS malfunction group (9 of 14). The difference was statistically significant (p=0.000001). Among 10 patients with under-drainage, 5 patients underwent shunt revision. The causes of the shunt malfunction included 3 cases of proximal occlusion and 2 cases of distal obstruction and valve malfunction. Conclusion : Under-drainage of CSF should be suspected if CSF lumbar tapping pressure is $35mmH_2O$ higher than the valve opening pressure and shunt malfunction evaluation or adjustment of the valve opening pressure should be made.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.49-54
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• 2010

The wooden cultural assets have the characteristics such as the fast spread of flame and leading to total destruction. Therefore, there is a need for a system for early countermeasure of recognized problem, along with the technological response for accurately recognizing the situation, for the prevention and early suppression of fire. To utilize such technology for detecting the situation through the latest ubiquitous technology and for a quick response to suppress fire, the ubiquitous sensor network (USN) technology, flame detector, image sensor, USN-based cultural asset disaster prevention management application case and malfunction identification system realization were examined in this study and the study result was presented focusing on the flame detector malfunction identification system for the ubiquitous-type cultural asset disaster prevention system.