• Journal of Fisheries and Marine Sciences Education
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• v.26 no.6
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• pp.1435-1441
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• 2014

The fire took place in the synthetic heat transfer fluid boiler used in production process of medium density fiberboard. This study investigated pressure distribution of the first, second and third passes and the temperature in the fire burner. The boiler's internal fluid is unsteady due to the out of order inverter. As the operation continues, the flame's flow and speed are unsteady. The synthetic heat transfer fluid leak spouted about 120kg/min in the form of vapor in the early period of the fire. The flame extended to the second and third passes. The highest temperature of the second and third pass is $1059^{\circ}C$ and $1007^{\circ}C$, respectively. The synthetic heat transfer fluid spouted through the cracked part of the fire box in the first pass and accumulated on the turn table. Therefore, it is expected that the temperature of the interior of the fire box is above $1200^{\circ}C$. The temperature of the burner rises to a maximum level several times in a short period. On account of that, several explosions occur in the fire burner. Pressure distribution at steady state in combustion furnace is 2~5mAq and pressure distribution at inverter under fault condition in combustion furnace is 10~-53mAq. The decrement of coil thickness measurement for synthetic heat transfer fluid boiler is 0~5mm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.1
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• pp.52-56
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• 2011

The ongoing Superconducting Fault Current Limiter(SFCL) development mainly has focused on the application of commercializaton and power system through combining with normal-conducting device, moving away from current-limiting method, which is solely dependant on the existing superconductor. Compared to the structural development above, on the other hand, the research on applying superconducting current-limiting element to SFCL, the heart of SFCL, still has a lot left to do, apart form traditional resistive type SFCL. In this study, we looked into the current limiting characteristic of SFCL using core and coil. YBCO coated conductor with stainless steel stabilizer layer was verified by the excellent of current-limiting element of the resistive type SFCL that has a high Jc and index as well as being superior in mechanical property. Also, we study temperature characteristics and resistance characteristics, max voltage, response time and current-limiting ability that can be an indicator as current-limiting element while applying to superconducting current-limiting element caused by variation of winding direction, winding ratio of SFCL using core and coil.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.8
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• pp.131-137
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• 2005

The purpose of this paper is to evaluate the axial magnetic flux measurement could be used as a tool of the condition monitoring system for the induction motor and to develope the diagnostic algerian for the electric motors. The magnetic leakage flux signal is captured by the flux coil located at the end of motor without the disturbance of the operation. And the signal is analyzed both time and frequency bases to detect the failure of the motor. Specific signature can be described in time and frequency domain for each faults of the motor. The spectrum of the signal was found more useful for the monitoring purpose. The supply voltage imbalance and tin to turn failure of the stator winding could be detected by analysing the specific sidebands of the axial flux and sideband of the rotor bar pass frequency with the high resolution spectrum. The goal of this study verity that the axial flux measurement for the induction motor is a powerful tool for the diagnostic method and develope the algorithm to detect the fault.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.5
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• pp.603-609
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• 2012

Wind energy is currently the fastest growing source of renewable energy used for electrical generation around world. Wind farms are adding a significant amount of electrical generation capacity. The increase in the number of wind farms has led to the need for more effective operation and maintenance procedures. Condition Monitoring System(CMS) can be used to aid plant owners in achieving these goals. Its aim is to provide operators with information regarding the health of their machines, which in turn, can help them improve operational efficiency. In this work, systematic design procedure for artificial neural network based normal behavior model which can be applied for fault detection of various devices is proposed. Furthermore, to verify the design method SCADA(Supervisor Control and Data Acquisition) data from 850KW wind turbine system installed in Beaung port were utilized.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.6
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• pp.675-680
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• 2012

Wind energy is currently the fastest growing source of renewable energy used for electrical generation around the world. Wind farms are adding a significant amount of electrical generation capacity. The increase in the number of wind farms has led to the need for more effective operation and maintenance. CMS(Condition Monitoring System) can be used to aid plant operator in achieving these goals. Its aim is to provide operators with information regarding th e health of their machine, which in turn, can help them improve operation efficiency. In this work, wind turbine fault diagnostic algorithm which can diagnose the mass unbalance and aerodynamic asymmetry of the blades is proposed. Proposed diagnostic algorithm utilizes both FFT(Fast Feurier Transform) of the signal from accelerometers installed inside of nacelle and simple diagnostic logic. Furthermore, to verify the applicability of the proposed system, 3W small sized wind turbine system is tested and physical experiments are carried out.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.7
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• pp.1438-1443
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• 2011

The increase of power capacity in the superconducting fault current limiter (SFCL) is essential for application into the power grid. To achieve this, when superconducting units were connected in series and parallel, the unbalanced quenching characteristics between superconducting units generated by different critical current behavior should be improved. In the transformer-type SFCL, the superconducting units connected in series could be simultaneously quenched by the connection of neutral lines between secondary coils and superconducting units. From this the consumed power in superconducting units was equally distributed. In addition, the more the turn ratio of the transformer was reduced, the more consumed power in the superconducting units was reduced by the decrease of the induction voltage generated in the superconducting units. From those results, the transformer-type SFCL using neutral lines could increase the power capacity of the SFCL by the equal power division into the superconducting units.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.287-292
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• 2021

In this paper, we propose an efficient CNN application method by analyzing the effect of activation function on the failure diagnosis of the inductive motor stator. Generally, the main purpose of the inductive motor stator failure diagnosis is to prevent the failure by rapidly diagnosing the minute turn short. In the application of activation function, experiments show that the Sigmoid function is 23.23% more useful in accuracy of diagnosis than the ReLu function, although it is shown that ReLu has superiority in overall fixer failure in utilizing the activation function.

• The Korean Society of Law and Medicine
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• v.12 no.1
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• pp.43-67
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• 2011

Humankind history is faced with one gigantic turning point due to development of Living genetically Modified Organisms. Food production by means of LMO is on the acceleration in an effort to solve the shortage of food problems. Food is also used as alternative energy source. Use of LMO product is not only limited to food and energy, but is actively utilized in various fields of medicines. This paper is first to check out the state of biomedicine developed and associated problems from industries that use LMO, after which we made an attempt on legislative approach to find out means of relief, through examples of such laws legislated for the sufferer from the adverse effect of the biomedicine. As for the liable subject to bear the responsibility for compensatory damage in a way of relieving the victim owing to adverse effect of biomedicine, those who manufactured and sold biomedicine and who are related to the damage to the victim due to the accident and medical doctors and pharmacists who prescribe and administer the medicine in question have been looked into. Accidents involving medicines and medical supplies could take place without reason for imputation on part of the liable subjects or fault of the victim, in which case the victim can't receive damage compensation from any of both parties. When such accidents happened turn out to be no fault accidents, introduction of damage relief measures might have to be reviewed against side effects of medicine and medical supplies as no fault compensation in order for actual relief to be possible. Talking about technicality of legislation, we can suggest a method of strengthening the accountability of manufacturer for stereotypical agenda on biomedicines by newly legislating special regulation with an issue that resists claim on risks associated with the development of medicine and incorporating the same into Manufactured Product Liability Law. After all, when an accident happens associated with biomedicine, the damage will be done to the consumer. And the consumer will be exposed to fatal danger even without the time to cope with potential risks associated with medicine and medical supplies they take. Therefore, it is necessary to protect the potential victim by having the manufacturer of biomedicines bear the liability of medical risks.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.1-12
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• 1996

To design the safe and rational rock slope, several rock slopes of roads in Kang-won area were analyzed, and the following results were obtained ; 1. The results were analyzed by stereographic projection at the rock slope that the joint was developed. All of the sloped which were designed by standard slope of rock was not considered that the joints were unstable. 2. The relation of rainfall and slope failure, as well as the danger of failure, was very high when the maximum hourly rainfall was larger than 20mm and when there was a 2-day cumulative rainfall that was larger than 200mm. 3. In the design of rock slope, operated by the stereographic projection considering discontinuity. If turn out unstable, it should be analyzed carefully using the limit equilibrium method. 4. In the design of rock slope, it is desirable to consider the discontinuity of rock(joint, bedding, fault).

• Economic and Environmental Geology
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• v.30 no.6
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• pp.613-624
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• 1997

A study of anisotropy of magnetic susceptibility (AMS) was conducted on the Ordovician-Eocene strata in the Taebaek area. The study area is a northeastern part of the Okchon belt, sometimes called as Paegunsan Synclinal Area. A total of 600 independently oriented samples were collected from 60 sites covering the whole area. With a few exception of late Cretaceous-Eocene volcanic rocks, all the sampled strata are nonmetamorphosed sedimentary rocks, mainly sandstones. Among the 60 sites, 5 sites showed flow lineation lying on the bedding plane, 11 sites showed load foliation parallel to the bedding plane, and 21 sites showed tectonic foliation unrelated to the bedding plane. The tectonic foliations are defined by $k_1-k_2$ ($k_{max}-k_{int}$) anisotropy plane, and are considered as a result of tectonic forces acted perpendicularly to the foliation plane in the geologic past. Regardless of sample-site locations, tectonic force directions defined by $k_3$ ($k_{min}$) axis perpendicular to the tectonic foliation are consistent among the strata of the same geologic age. In the course of geologic time, however, the tectonic force directions showed a clockwise rotation: approximately E-W in the Ordovician sites, NW-SE in the Permian sites, N-S in the Triassic sites, and lastly NE-SW in the late Cretaceous-Eocene sites. The pre-Permian directions showed better clustering in the in-situ (geographic) coordinates, while the younger directions become better clustered after the bedding-tilt correction. It is interpreted that the major tectonic structures of the Taebaek area were controlled by the above-mentioned tectonic forces: The Paegunsan Syncline and the Hambaeksan Fault must have been generated by the NW-SE force of late Permian-early Triassic time. It was then reactivated in the reverse (dextral) sense by the N-S force of Triassic time. The Osipchon Fault in the eastern part of the study area was either generated or reactivated by the NE-SW force of late Cretaceous-Eocene time. The Permo-Triassic NW-SE force should be an expression of the Songnim Disturbance in the Korean peninsula, which is in turn related with the SCB/NCB collision in China.