• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.6
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• pp.605-610
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• 2016

The ELCB(: Earth Leakage Circuit Breaker) is the only way being used to prevent accidents from happening caused by electrical disaster. However, the existing ELCB has a limit to prevent damages to life and property due to a electric fire and a human body electric shock caused by the resistive leakage current, because of detecting the total leakage current in the block range of 15mA~30mA. It also has problems such as reduced productivity and reliability due to malfunctions by capacitive leakage currents. In this study, we have implemented the algorithm for the resistive leakage current detection technique and developed the resistive leakage current detection module based on a MSP430 processor, 16bit signal processor and this module can be operated in a desired block threshold within 0.03 seconds as specified in KS C 4613.

• Fire Science and Engineering
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• v.26 no.4
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• pp.82-88
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• 2012

To analyze the thermal characteristics of wire connection part that is connected to a screw-clamping terminal block depending on screw torque, the normal screw torque defined in KS C 2625 and the abnormal screw torque that can occur due to loosened screws resulting from defective work or aged deterioration were used as experimental variables. After the same load was applied to normal and abnormal screw torques, the thermal characteristics of the wire connector were measured and compared with a thermal imaging camera. The findings from this study will be used to detect heating due to defective screw torque at terminal block connections during electric safety inspection in the future and minimize the hazard of electric fire.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.6
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• pp.464-469
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• 2011

Introduction: As dental implant surgery is becoming increasingly popular, it has become one of the causes for the hypesthesia of the inferior alveolar nerve, along with other surgical procedures, such as a third molar extraction. In addition, it tends to cause legal problems between the operator and patient. Therefore, there must be a proper method that is reliable, objective and economical to assess the nerve impairment. For this reason, an attempt was made to use an Electric Pulp Tester to assess inferior alveolar nerve block anesthesia. Materials and Methods: Thirty patients were tested. Electric pulp testing of the lower jaw skin was performed at the three different times, before anesthesia, at the onset of sensory changes and after 15 minutes waiting from the onset, and on the 10 points of the chin, which produced 10 sections on the skin area. Results: Twenty seven patients (90%) could feel the electric stimulus on the chin at all 10 points before local anesthesia and the scores represent the statistical differences between the right and left points except R4 and L4. After anesthesia, the difference between the right and left points (L3-R3, L4-R4, L5-R5) increased significantly with time but two points (L2, R2) showed no significant difference. The scores on the left chin (L3, L4, L5) increased, whereas the other points (R1-R5, L1, L2) showed no significant differences. Conclusion: This study highlights the potential clinical use of an electric pulp tester for an assessment of inferior alveolar nerve impairment.

• Journal of the Korean Institute of Gas
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• v.3 no.3 s.8
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• pp.23-28
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• 1999

Variation of explosion characteristics by the blocks in closed vessel was investigated to analyse the effect of the block volume(volume blockage) and the surface area of the blocks(ratio of block surface area to vessel volume). Volume and surface area of blocks in explosion vessel were changed by the combination of blocks. The volume of explosion vessels was 270 liter, and the LPG-air or NG-air mixtures were ignited by the electric spark. Explosion pressure was measured with the strain type pressure transducer. From the experimental results, explosion pressure was decreased by the increase of the volume blockage and the block surface area. And the decrease of explosion pressure was more affected by the volume blockage than the surface area.

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2062-2069
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• 2015

In the series hybrid active power filter (SHAPF) with magnetic flux compensation (MFC), the system current oscillate in the experimental results when adding the same phase harmonic current command in current control block. This condition endangers the security of the SHAPF. Taking the digit period average arithmetic as example, this paper explains the inter-harmonics current oscillation in the experiment. The conclusion is that the SHAPF is unstable to the inter-harmonics current in theory. Limited by the capacity of the inverter, the system current and the inverter output current do not increase to infinite. At last, some methods are proposed to solve this problem. From the practical viewpoint, the voltage feed-forward control is easy to achieve. It can suppress the current oscillation problems, and also improve the filtering effect. The feasibility of the methods is validated by both the emulation and experiment results.

• The Korean Journal of Ceramics
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• v.5 no.4
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• pp.353-356
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• 1999

Highly proten-conductive elastic composites have been successfully prepared from $H_3PO_4$-doped silica gel and styrene-ethylene-butylene-styrene block elastic copolymer. In addition solid state electric double-layer capacitors have been fabricated using the composite as an electrolyte and activated carbon powders(ACP) hybridized with the composite as a polrizable electrode. The cyclic voltammogram of the electric double-layer capacitor fabricated demonstrated that electric charge was stored in the elecric double-layer at the interface between the polarizable electrode and the electrolyte. The value of capacitance of the capacitor was 10 F/(gram of total ACP), which was comparable to that of the capacitors using conventional liquid electrolytes.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.6
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• pp.753-763
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• 2016

High temperature sodium/sulfur battery(Na/S battery) has good electrochemical properties, but, the battery has some problems such as explosion and corrosion at al. because of using the liquid electrodes at high temperature and production of high corrosion. Room temperature sodium/sulfur batteries (NAS batteries) is developed to resolve of the battery problem. To recently, room temperature sodium/sulfur batteries has higher discharge capacity than its of lithium ion battery, however, cycle life of the battery is shorter. Because, the sulfur electrode and electrolyte have some problem such as polysulfide resolution in electrolyte and reaction of anode material and polysulfide. Cycle life of the battery is improved by decrease of polysulfide resolution in electrolyte and block of reaction between anode material and polysulfide. If room temperature sodium/sulfur batteries (NAS batteries) with low cost and high capacity improves cycle life, the batteries will be commercialized batteries for electric storage, electric vehicle, and mobile electric items.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.613-616
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• 2010

본 논문에서는 새로운 움직임 추정(motion estimation, ME) 방식을 사용한 프레임 비율 변환(frame rate conversion, FRC) 기법에 대해 제안한다. 기존의 프레임 비율 변환을 위한 움직임 추정 방식은 영상 압축에서 사용되고 있는 SAD를 사용하여 블록(block) 단위로 움직임 벡터를 추정하는 방식에 기초를 두고 있다. 그러나 잔여 신호(residual signal)를 저장하는 영상 압축과 달리, 잘못된 움직임 추정은 합성된 출력 영상에서 심각한 품질 저하를 가져올 수 있다. 이를 보완하기 위해 움직임 개선(motion refinement, MR)이 사용되고 있지만, 근본적인 해결을 위해서는 정확한 움직임 추정 알고리즘 사용이 필요하다. 특히 SAD를 통한 움직임 추정은 고르지 못한 움직임 벡터장(motion vector field, MVF)을 형성할 수 있으며, 종래의 연구에서 이를 해결하기 위해 SAD(sum of absolute difference)에 벡터의 공간제약(spatial constraint) 항목을 추가하여 비교적 고른 움직임 벡터장을 형성하는 방식이 제시되었다. SAD와 공간 제약 항목의 반영 비율에 따라 움직임 벡터의 중요성과 움직임 벡터장의 일관성이 서로 상충하는데, 기존의 방식은 이 비율을 일정한 상수(constant)값을 사용하고 있으며, 이러한 방식은 이미지의 특성에 따라 결과가 달라진다. 본 논문에서는 SAD와 공간 제약 항목 사이의 반영 비율을 이미지의 특성에 적응하는 방식을 사용하는 움직임 예측을 제시하고, 수행한 결과를 기존의 방식에 의한 결과와 비교하였다.

• Fire Science and Engineering
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• v.23 no.2
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• pp.1-5
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• 2009

We studies wish to investigated establishment form of cabinet board, and confirm possibility of electrical disaster prevention through reappearance experiment of odor detection system. Established breaker consists of MCCB, RCD order in cabinet board for house, but industry is used together with. When imposed shock using shaker to terminal block that contact becomes in appropriate, flame was made sure. According to result that experiment attaching odor capsule in terminal block, capsule commissioned exactly by occurred heat. According to establishment position of sensor, difference of inspection time was about 10 seconds. Estimate odor inspection system by thing which electrical device accident prevention is available. When there is abnormal generated heat in connection of electric wire, accident prevention estimates that is possible by giving an alarm state of overheat to administrator.

• The Korean Journal of Pain
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• v.11 no.1
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• pp.119-123
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• 1998

It is well known that many patients with trigeminal neuralgia suffer from electric shock-like stabbing pains. The pain can be triggered by nonnoxious stimuli such as touching of the face, chewing, talking or swallowing. This 62 year old woman was urgently admitted to the internal medicine department due to abdominal distention and severe general weakness. She has suffered characteristic violent pain triggered by chewing and swallowing for little over 4 years. This resulted in poor oral feeding for prolonged period which left her severely debilitated. The large amount of ascites that developed 20 days before admission and extreme emaciation forced her to bed rest. She also suffered from Herpes Zoster. After medical treatment to improve liver function and severe pain was persisted, the patient was referred to our department for control of pain. We performed right mandibular block with 1% dibucaine 0.4 ml and the effect was excellent. After the pain had subsided, patient was able to take meals more comfortably and improved liver function returned.