• 한국전기전자재료학회논문지
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• 제15권9호
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• pp.812-817
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• 2002

• 한국전기전자재료학회논문지
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• 제18권8호
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• pp.766-771
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• 2005

In this study, PD(partial discharge) signals which occur at stator coil of traction Motor are acquired these data are used for classifying the PD sources. NN(neural network) has recently applied to classify the PD pattern. The PD data are used for the learning process to classify PD sources. The PD data come from normal specimen and defective specimens such as internal void discharges, slot discharges and surface discharges. PD distribution parameters are calculated from a set of the data, which is used to realize diagnostic algorithm. NN which applies distribution parameters is useful to classify the PD patterns of defective sources generating in stator coil of traction motor.

• 환경생물
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• 제22권1호
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• pp.89-92
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• 2004

The effects of different light quality on the change of membrane potential difference (PD) of the guard cell in the intact leaf have been investigated. The mombrane PD was about -5.5 mV by white light of 600 $\mu$moles $m^{-2}\; s^{-1}$. The mean PD of change caused by red light was about -5.2 mV at the light intensity of 80 $\mu$moles $m^{-2}\; s^{-1}$. Membrane PD of guard cells in response to blue light was saturated at low light intensity. However, red and green light enhanced the change of membrane PD of guard cells with increasing intensity. In green light the biggest change of memrane PD was around -4 mV, whereas, with blue light the change of of memrane PD was around -2 mV. Accordingly, the membrane PD of guard cell showed the different degree of hyper-polarization by each wavelength.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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• pp.152-155
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• 2002

During normal operation, partial discharge(PD) tests were performed using turbine generator analyzer(TGA) in high voltage motor. Epoxy-mica couplers are installed at motor terminal and analyzed PD signal using TGA. #A motor stator insulation is good because small partial discharges are detected PD pattern show that PD occurs in insulation. PD of #B motor is larger than that of #A motor and PD pattern show that positive PD larger than negative PD. It means that PD occurs between insulation and slot. And A phase PD magnitude of #B motor is large and high compare with any other phase. Therefore wedge, core and slot of #B motor need to check and repair.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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• pp.199-202
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• 2002

During normal operation, partial discharge(PD) tests were performed using turbine generator analyzer(TGA) in high voltage motor. Epoxy-mica couplers are installed at motor terminal and analyzed PD signal using TGA. #A motor stator insulation is good because small partial discharges are detected. PD pattern show that PD occurs in insulation. PD of #B motor is larger than that of #A motor and PD pattern show that positive PD larger than negative PD. It means that PD occurs between insulation and slot. And A phase PD magnitude of #B motor is large and high compare with any other phase. Therefore wedge, core and slot of #B motor need to check and repair.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권5호
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• pp.177-181
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• 2003

Partial discharge pulse shapes from variable PD (partial discharge) sources sustain many characteristics such as types of PD. Ultra high frequency antennas have wide bandwidth from 30KHz to 2㎓. Therefore, signals taken from a UHF antenna have important attributes (rising time, falling time, shape factor, etc.) for electromagnetic sources, such as PD sources. We investigated PD pulse shapes from several PD sources using a UHF antenna and the results were used for classification of PD sources. Features for discrimination are extracted from frequency distribution and LPC (Linear Prediction Coefficient) of time signal. RBFN are used for investigating the possibility of classification of multi-PD sources.

• E2M - 전기 전자와 첨단 소재
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• 제11권11호
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• pp.1-8
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• 1998

This paper presents an arificial neuro-fuzzy technique based prtial discharge (PD) pattern classifier to power system application. This may require a complicated analysis method employ -ing an experts system due to very complex progressing discharge form under exter-nal stress. After referring briefly to the developments of artificical neural network based PD measurements, the paper outlines how the introduction of new emerging technology has resulted in the design of a number of PD diagnostic systems for practical applicaton of residual lifetime prediction. The appropriate PD data base structure and selection of learning data size of PD pattern based on fractal dimentsional and 3-D PD-normalization, extraction of relevant characteristic fea-ture of PD recognition are discussed. Some practical aspects encountered with unknown stress in the neuro-fuzzy techniques based real time PD recognition are also addressed.

• 폴리머
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• 제33권6호
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• pp.615-619
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• 2009

Pd-POSS 나노입자는 palladium(II) acetate와 octa(3-aminopropyl) octasilsesquioxane octahydrochloride(POSS-${NH_3}^+$)를 메탄올 용매 하에 상온에서 제조하였다. POSS-${NH_3}^+$를 이용한 Pd-POSS 나노입자의 크기는 약 60-80 nm의 직경인 구형으로 관찰되었다. 반면에, POSS-${NH_3}^+$를 이용하지 않은 Pd 나노입자의 경우에는 4 nm 정도의 크기를 가진 것으로 확인되었다. Pd-POSS 나노입자와 poly(acrylic acid)(PAA)를 이용한 Pd-POSS/PAA 나노복합체는 양전하를 띠는 Pd-POSS 나노입자와 음전하를 띠는 PAA의 카르복실레이트 그룹의 정전기적 인력을 이용하여 제조하였다. Pd-POSS 나노입자는 유기고분자인 PAA에 의하여 일렬로 나열되어 있는 라인형태의 구조로 연결되었다. 즉, PAA를 cross-linker로 이용하여 Pd-POSS의 구조를 제어한 나노복합체를 합성하였다. Pd-POSS/PAA 나노복합체의 구조 및 형태와 열적 안정성은 FE-SEM, AFM, TEM, FT-IR과 TGA를 통하여 분석하였다.

• 한국표면공학회지
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• 제50권5호
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• pp.411-420
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• 2017

In this paper, two methods of making the Pd-added $SnO_2$ ($Pd-SnO_2$) powder with pure tetragonal phase by the hydrazine method were suggested and compared in terms of crystal structure, surface morphology, and alcohol gas response. One of the addition methods is to use $PdCl_2$ as a Pd source, the other is to use Pd-based organic with oleylamine (OAM). When Pd concentration was increased from 0 to 5 wt%, the average grain size of $Pd-SnO_2$ made with Pd-OAM were decreased from 32 to 12 nm. In the case of using with $PdCl_2$, grain size of the $PdCl_2$ fell to less than 10 nm. However, agglomerated and extruded surface morphology was observed for the films with Pd addition over 4 wt%. The crack-free $Pd-SnO_2$ thick films were able to successfully fill the $30{\mu}m$ gap of patterned Pt electrodes by optimized ink dropping method. Also, the 2 wt% $Pd-SnO_2$ thick film made with PdCl2 showed gas responses ($R_{air}/R_{gas}$) of 3.7, 5.7 and 9.0 at alcohol concentrations of 10, 50 and 100 ppm, respectively. On the other hand, the prepared 3 wt% $Pd-SnO_2$ thick film with Pd-OAM exhibited very excellent responses of 3.4, 6.8 and 12.2 at the equivalent measurement conditions, respectively. The 3 wt% $Pd-SnO_2$ thick film with Pd-OAM has a specific surface area of $31.39m^2/g$.

• 한국진공학회지
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• 제12권4호
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• pp.218-227
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• 2003

AlGaAs/GaAs HBT 에미터 오믹 접촉을 위해 n형 InGaAs에 대한 Pd/Si/Ti/Pt 및 Pd/Si/Pd/Ti/Au 오믹 접촉 특성을 조사하였다. Pd/Si/Ti/Pt 오믹 접촉의 경우, 증착 상태에서는 접촉 비저항을 측정할 수 없을 정도의 비오믹 특성을 보였으며, $375^{\circ}C$에서 10초 동안 열처리한 경우 $5\times10^{-3}\Omega\textrm{cm}^2$의 높은 접촉 비저항을 나타내었다. 그러나 열처리 조건을 $425^{\circ}C$, 10초로 변화시킬 경우 $2\times10^{-6}\Omega\textrm{cm}^2$의 낮은 접촉 비저항을 나타내었다. Pd/Si/Pd/Ti/Au 오믹 접촉의 경우, $450^{\circ}C$까지의 열처리 동안에 전반적으로 우수한 오믹 특성을 나타내어 $400^{\circ}C$, 20초의 급속 열처리 조건에서 최저 $3.9\times10^{-7}\Omega\textrm{cm}^2$의 접촉 비저항을 나타내었다. 두 오믹 접촉 모두 오믹 재료와 InGaAs의 평활한 계면을 유지하면서 우수한 오믹 특성을 나타내어, 화합물 반도체 소자의 오믹 접촉으로 충분히 응용 가능하였다. Pd/Si/Ti/Pt 및 Pd/Si/Pd/Ti/Au를 AlGaAs/GaAs HBT의 에미터 오믹 접촉으로 사용하여 제작된 HBT 소자의 고주파 특성을 측정한 결과, 차단 주파수가 각각 63.9 ㎓ 및 74.4 ㎓로, 또한 최대공진 주파수가 각각 50.1 ㎓ 및 52.5 ㎓로 우수한 작동특성을 보였다.