• 전기의세계
• /
• 제28권10호
• /
• pp.48-54
• /
• 1979

The electrification phenomena of polymerized materials is governed by the competitive processes of the charge generation and the charge dissipation. In this paper, The charged particles were supplied on the naked upper surface of the polyethylene film from a point corona discharge with a screen electrode which controls the potential difference across the film. The charging current with the corona charging was found to be larger than that obtained with the electric charging on the MIM structure and the discharge current was found to flow in the same direction as that of the charging current. these results can suggest that the charge injection occurs from the interface between the polethylene surface and the accumulated charge layer, the injected charge are trapped and the space charge is established.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
• /
• pp.279-280
• /
• 2005

We have designed a single gap transflective liquid crystal display (LCD) driven by a fringe electric field and vertical field. The conventional FFS mode does not have an electrode on top substrate, it shows not only slow response time due to weak electric field but also slow discharging problem when electrostatic field is generated after fabricating the cell. To solve these problems, transflective LCD with ITO coated upper substrate was suggested but the transmittance was reduced significantly due to effects from vertical field. Hence, in the present paper, new transflective LCD with ITO coating only in the reflective region was characterized.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제55권6호
• /
• pp.323-327
• /
• 2006

In this paper a new wire-wire discharge system with a slit dielectric harrier has been proposed, and, its corona discharge and ozone generation characteristics have been investigated experimentally. When the slit mica barrier is installed between corona wires, instead of the grounded plate electrode, a significant increase in the generation of ozone, about 2.2 times higher than that of the conventional ones without the slit harrier, could be obtained. Photographs show that this type of discharge system with a slit barrier was found to produce a corona discharge twice, once from the upper and bottom corona wires, and. again from both sides of surfaces and slits of the slit barrier. As a result, the proposed discharge system has the potential to increase significantly ozone production and it may be useful as an effective means for removing pollutant gases.

• Journal of Welding and Joining
• /
• 제35권2호
• /
• pp.1-5
• /
• 2017

Many microelectronic devices are miniaturizing the capacitance density and the size of the capacitor. Along with this miniaturization of electronic circuits, tantalum (Ta) capacitors have been on the market due to its large demands worldwide and advantages such as high volumetric efficiency, low temperature coefficient of capacitance, high stability and reliability. During a tantalum capacitor manufacturing process, arc welding has been used to weld base frame and sub frame. This arc welding may have limitations since the downsizing of the weldment depends on the size of welding electrode and the contact time may prevent from improving productivity. Therefore, to solve these problems, this study applies laser spot welding to weld nickel (Ni) and Au-Sn-Ni alloy using CW IR fiber laser with lap joint geometry. All laser parameters are fixed and the only control variable is laser irradiance time. Four different shapes, such as no melting upper workpiece, asymmetric spherical-shaped weldment, symmetric weldment, and, excessive weldment, are observed. This shape may be due to different temperature distribution and flow pattern during the laser spot cutting.

• 한국안전학회지
• /
• 제7권2호
• /
• pp.57-62
• /
• 1992

In this thesis, the electrification phenomenon was studied by measurement of charging current and discharging current in polymers when the carriers generated by corona discharge were supplied to the surface of polymers. Corona charging current of PVC, polar and noncrystalline polymer, was larger than that of nonpolar and amorphous polymers. Corona charging current on the specimen of naked upper surface (CIM) was larger than charging current on the specimen of electrode made. Carrier injection differed from interfacial phase of polymer surFace. The transfer phenomenon vaned with chemical structure of polymer and then the polar effect of PVC was remarkable because of large electron affinity of Cl. In the characteristics of discharging current of PVC, the abnormal current was observed. It was supposed that this phenomena presented the trap of injected carriers in PVC and that static electricity phenomenon was generated by trap.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1994년도 춘계학술대회 논문집
• /
• pp.67-70
• /
• 1994

On this study, we fabricated humudity sensor with polyimide thin film from the nonaqueous emulsion by the electrophoretic deposition as a function of film thickness. then evaluated performance of the sensor with increasing relative humidity if constant temperature constant humidity chamber, which is electronically controlled. we designed upper electrode of the sensor to brush type to make moisture particles permeate into the polymer bulk. sensing properties of the sensor on % RH shows proportion on the low %RH. Fer the 30V-30S- 200$^{\circ}C$ sample, percentage changing of capacitance on from 30 %RH to 90 %RH is 45.8 %, and increasing rate per 1 % RH of capacitance is 11.25 pF

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 하계학술대회 논문집 B
• /
• pp.1365-1367
• /
• 2003

In this paper, element technologies such as soldering. arrangement and lamination processes for photovoltaic module manufacture were examined and described as main processes. Especially solder paste and temperature condition in soldering process, loss factor in arrangement process and process conditions in lamination process are investigated to minimize the electrical loss. As a results, temperature condition in soldering process was found to be critical to contact resistance of electrode and life-time. Productivity of the process decreases dramatically by physical damage during arrangement process. Pressure level and press condition of upper chamber in lamination process were important parameters for the reliability. According to the test result of photovoltaic module, electrical properties dropped about $5{\sim}25%$ after 5 years.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
• /
• pp.377-380
• /
• 2004

The phase transition between amorphous and crystalline states in chalcogenide semiconductor films can controlled by electric pulses or pulsed laser beam; hence some chalcogenide semiconductor films can be applied to electrically write/erase nonvolatile memory devices, where the low conductive amorphous state and the high conductive crystalline state are assigned to binary states. GeSbTe(GST), AsSbTe(AST), SeSbTe(SST) used to phase change materials by appling electrical pulses. Thickness of ternary chalcogenide thin films have about 100nm. Upper and lower electrode were made of Al. It is compared with I-V characteristics after impress the variable pulses.

• 한국기계기술학회지
• /
• 제13권4호
• /
• pp.143-148
• /
• 2011

This study analyzes the resistance spot weldability of DP60 steels. To analyze the resistance spot weldability of DP60 steels, tensile strength test and macro-section test were conducted for the resistance spot welds. Acceptable welding conditions were determined as a function of the resistance spot welding process parameters such as electrode force, welding time, and welding current. The lower limit of the welding lobe was the minimum shear tension strength for 590MPa-grade steel while the upper limit was determined whether or not expulsion was detected.

• 재활치료과학
• /
• 제8권1호
• /
• pp.41-50
• /
• 2019

목적: 본 연구의 목적은 건강한 성인을 대상으로 양측상지기능 훈련을 통해서 활성화 되는 대뇌 연결성에서 상상 훈련과 신체적 수행 간에 차이가 있는지를 알아보고자 한다. 연구방법: 연구 대상자는 건강한 성인 1명으로 상상훈련과 신체적 수행 시 EEG 측정이 이루어졌다. 양측상지기능 훈련은 대칭 과제와 비대칭 과제로 구성되었다. 대칭 과제는 양손으로 박스를 잡고 동시에 위의 선반으로 올렸다가 다시 내려놓는 과제이고, 비대칭 과제는 한 손으로 병을 잡고 다른 한 손으로 뚜껑을 여는 과제였다. EEG 전극은 Fp1, Fp2, F3, F4, T3, T4, P3 및 P4에 부착되었다. 데이터 분석은 EEG 전극 쌍 간의 상관 분석을 위해 Cross-Line Mapping을 사용하였다. 결론: 본 연구 결과 대칭 및 비대칭의 양측 상지 과제에서 대뇌 연결성 패턴은 운동과 감각 영역에서 유사한 패턴을 가지는 것으로 나타났다. 또한 본 연구를 통해 양측상지기능 훈련 시 상상훈련보다 신체적 수행에서 대뇌 연결성이 더 높은 상호상관을 갖는다는 것을 확인하였다.