• 전기학회논문지
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• 제58권5호
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• pp.989-993
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• 2009

Triple junction which consists of three media(electrode, insulator, and gas) should be considered in designing of high voltage equipments due to the electric field enhancement. In this paper, positive lightning impulse breakdown voltage is predicted based on the streamer theory for simplified insulator models and 72.5kV spacer with varying the triple junction geometry and gas pressure, and the results are compared to the experimental results. The electric field coefficient concept is also applied in order to evaluate the partial discharge inception voltage and the surface flashover voltage from the streamer inception voltage. The application of this method using the constant electric field coefficient of 1.3 and 0.66 is possible for evaluating the triple-junction insulation of the simplified insulator and the 72.5kV spacer respectively. The error rate is under 10%.

• 한국전기전자재료학회논문지
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• 제33권3호
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• pp.225-230
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• 2020

Recently, with the miniaturization of GIS, there is a need for the miniaturization of spacers as accessories. Miniaturized spacers make it difficult to secure adequate insulation distances, resulting in a more concentrated electric field at the triple junction of high-voltage (HV) conductor-insulator (spacer)-insulation gas (SF₆), which is a weakness in GIS. Therefore, by introducing a new concept design technology, functionally graded material (FGM), which is recently applied to various materials and parts industries, three-dimensional control of the dielectric constant distribution in a spacer can be expected to alleviate triple-junction electric field occupancy and improve insulation performance. In this study, we propose an optimized model using NSGA-II to optimize the permittivity distribution of FGM applied spacer.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.581-586
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• 2009

Knowledge of ground thermal properties is most important for the proper design of large scale BHE(borehole heat exchanger) systems. The type, pipe size and thermal performance of the BHE is highly dependent on the ground source heatpump system-efficiency and instruction cost. Thermal response tests with mobile measurement devices were developed primarily for insitu determination of design data for large diameter BHE for triple-U spacer apply. The main purpose has been to determine insitu values of effective ground thermal conductivity and thermal resistance, including the effect of ground-water flow and natural convection in the boreholes. The test rig is set up on a some trailer, and contains a circulation pump, a inline heater, temperature sensors, flow meter, power analysis meter and a data logger for recording the temperature, fluid flow data. A constant heat power is injected into the borehole through the tripl-U pipes system of test rig and the resulting temperature change in the borehole is recorded. The recorded temperature data are analysed with a line-source model, which gives the effective insitu values of rock thermal conductivity and borehole thermal resistance of large diameter BHE for spacer apply.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.289-292
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• 1990

This study is to develope a spacer having almost uniform field distribution along the profile by controlling the high electric field in tensification at earthed part, especially triple junction in the spacer-electrode-gas boundary interface. Based on the extensive field calculation using CSM, a model spacer has been manufactured and tested. The test results show that the breakdown strength of the spacer is almost same as that of SF6 gas itself without spacer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1681-1683
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• 1998

Unlike AC, DC dielectric characteristics of the spacer are very influenced by the quantity and the distribution of surface charges. A general impression of the distribution of surface charges is obtained if electrostatic powders are sprinkled over the surface. The distribution of surface charge was investigated with dust figures. Mechanism of charge accumulation on the spacer of $SF_6$ GIS has been studied using various types of model spacers which have different depths. As a result, it was found that charge accumulation was dominantly influenced by the normal component of the electric field and the usage of embedded electrodes was an adequate method to lessen field concentration around the triple junction. The guide of the optimum depth of the spacer was proposed.

• 에너지공학
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• 제1권1호
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• pp.66-75
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• 1992

이중창의 열전달 성능을 수치해석과 실험적 방법을 통하여 조사하였다. 이중창 사이의 간격이 0.5cm에서 10cm사이의 실제적인 범위에서 이중창 사이의 간격이 작을 때에는 전도에 의한 열전달이 두드러졌으며 이중창 사이의 간격이 넓어지고 Rayleigh 수가 높은 영역에서는 대류에 의한 열전달이 크게 나타나 이중창 간격이 넓어진 이점을 크게 상쇄시켰다. 이와 같은 이중창 단열문제에 대한 보완책으로 이중창 중앙에 하나의 유리창을 더 설치한 3중창 경우에 대해 대류열전달 감소효과와 복사열차폐(radiation shield) 효과를 검토하였으며 또한 이중창 중간 높이에 스페이서(spacer)를 설치하여 대류유동 강도를 줄이는 방안 등에 대한 분석이 이루어졌다. 3중창을 사용한 경우에는 이중창에 비해 30-50%, 이중창에 스페이서를 설치한 경우에는 l0% 정도의 에너지 절약 효과를 기대할 수 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.402-403
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• 2007

High-efficiency white organic light-emitting diodes (WOLEDs) were fabricated with two emissive layers and a spacer was sandwiched between two phosphorescent dyes which were, bis(3,5-Difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl) iridium III (FIrpic) as the blue emission and bis(5-acetyl-2-phenylpyridinato-N,C2') acetylacetonate $((acppy)_2Ir(acac))$ as the red emission. This spacer effectively prevented a triple-triple energy transfer between the two phosphorescent emissive layers with blue and red emission that was showed a improved lifetime. The white device showed Commission Internationale De L'Eclairage $(CIE_{x,y})$ coordinates of (0.33, 0.42) at $22400\;cd/m^2$, a maximum luminance of $27300\;cd/m^2\;at\;0.388\;mA/cm^2$, and a maximum luminous efficiency of 26.9 cd/A.

• Biomolecules & Therapeutics
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• 제30권2호
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• pp.191-202
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• 2022

Tetrazoles were designed and synthesized as potential inhibitors of triple monoamine neurotransmitters (dopamine, norepinephrine, serotonin) reuptake based on the functional and docking simulation of compound 6 which were performed in a previous study. The compound structure consisted of a tetrazole-linker (n)-piperidine/piperazine-spacer (m)-phenyl ring, with tetrazole attached to two phenyl rings (R1 and R2). Altering the carbon number in the linker (n) from 3 to 4 and in the spacer (m) from 0 to 1 increased the potency of serotonin reuptake inhibition. Depending on the nature of piperidine/piperazine, the substituents at R1 and R2 exerted various effects in determining their inhibitory effects on monoamine reuptake. Docking study showed that the selectivity of tetrazole for different transporters was determined based on multiple interactions with various residues on transporters, including hydrophobic residues on transmembrane domains 1, 3, 6, and 8. Co-expression of dopamine transporter, which lowers dopamine concentration in the biophase by uptaking dopamine into the cells, inhibited the dopamine-induced endoctytosis of dopamine D₂ receptor. When tested for compound 40 and 56, compound 40 which has more potent inhibitory activity on dopamine reuptake more strongly disinhibited the inhibitory activity of dopamine transporter on the endocytosis of dopamine D₂ receptor. Overall, we identified candidate inhibitors of triple monoamine neurotransmitter reuptake and provided a theoretical background for identifying such neurotransmitter modifiers for developing novel therapeutic agents of various neuropsychiatric disorders.

• 설비공학논문집
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• 제19권4호
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• pp.333-338
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• 2007

The object of this study is to find the optimal insulation design conditions of a HTS power cable cryostat. The optimum condition of a cable cryostat is obtained by varying types of MLIs, cable core weights, spacer diameters, winding pitches and MLI layer numbers. As the weight of cable core is increased, conduction heat transfer from surroundings to cable cryostat is increased. But as the spacer pitch is increased from 120 mm to 200 mm, the heat leak of cable cryostat remains almost constant. The optimal number of MLI layers is suggested. Double ply MLI is more effective than triple ply MLI and the insulation effect is best when the number of MLI layers is 36.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2597-2602
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• 2012

Novel 1,4-substituted piperazine derivatives 5, Series A and B were designed by fragment analysis and molecular modification of 4 selected piperazine-containing compounds which possess antidepressant activity. We synthesized new 39 analogues of Series A and 10 compounds of Series B, respectively. The antidepressant screening against DA, NE, and serotonin neurotransmitter uptake inhibition was carried out using the Neurotransmitter Transporter Uptake Assay Kit. The compounds in Series B showed relatively higher reuptake inhibitory activity for SERT, NET, and DAT than those in Series A. The length of spacer between the central piperazine core and the terminal phenyl ring substituted at the piperazine ring in Series B seems to exert an important role in the activity.