• 제목/요약/키워드: Base Density

검색결과 672건 처리시간 0.03초

지구단위계획(地區單位計劃)에서 건축(建築) 규모설정(規模設定)에 관한 연구(硏究) (A study on the suitable of building size in district units plan)

  • 이원근;이재국;도규환
    • 한국디지털건축인테리어학회논문집
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    • 제3권1호
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    • pp.39-49
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    • 2003
  • The height provisions, by the urban planning, describe the hightest height per width division, also define oblique line limitation by road without mentioning the highest per width division. Therefore this study will be a basic model for the standard of measuring the highest height per width division analysizing the propriety of current standard of oblique limitation. This technique is prepared to prevent the confusion and to complements the existing planning method. Therefore, it takes more time to establish this new method and to apply it to the existing condition. This study reviewed density control in District Units Plan, based on the guidelines of density, which included height, ratio of total floor to ground area, and land distribution. This study aims to provide efficient analysis by using current oblique limitation provisions Thus, proving the area rations of general residential areas are decreasing. Since the purpose of the District Units Plan is to avoid confusion and help ease the existing problematic conditions which have risen from the two above-mentioned conventional systems, further observation and research on these areas are necessary.

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4.5 kV급 Super Junction IGBT의 Pillar 간격에 따른 전기적 특성 분석 (Analysis of Electrical Characteristics According to the Pillar Spacing of 4.5 kV Super Junction IGBT)

  • 이건희;안병섭;강이구
    • 한국전기전자재료학회논문지
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    • 제33권3호
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    • pp.173-176
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    • 2020
  • This study focuses on a pillar in which is implanted a P-type maneuver under a P base. This structure is called a super junction structure. By inserting the pillar, the electric field concentrated on the P base is shared by the pillar, so the columns can be dispersed while maintaining a high breakdown voltage. Ten pillars were generated during the multi epitaxial process. The interval between pillars is varied to optimize the electric field to be concentrated on the pillar at a threshold voltage of 6 V, a yield voltage of 4,500 V, and an on-state voltage drop of 3.8 V. The density of the filler gradually decreased when the interval was extended by implanting a filler with the same density. The results confirmed that the size of the depletion layer between the filler and the N-epitaxy layer was reduced, and the current flowing along the N-epitaxy layer was increased. As the interval between the fillers decreased, the cost of the epitaxial process also decreased. However, it is possible to confirm the trade-off relationship that deteriorated the electrical characteristics and efficiency.

방습 효과가 우수한 환경친화적 방습지(제1보) -방습제의 특성- (Environmentally Friendly Moisture-proof Paper with Superior Moisture Proof Property (I) -Properties of Moisture Proof Chemicals-)

  • 유재국;조욱기;이명구
    • 펄프종이기술
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    • 제33권4호
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    • pp.15-20
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    • 2001
  • The function of the moisture-proof paper is to prevent moisture from adsorbing into the packed goods. Water-vapor transmission rate of the moisture-proof paper should be less than 100g/$m^2$.24hr and the optimum rate would be less than 50g/$m^2$.24hr. In general the moisture-proof paper has been made by laminating polyethylene or polypropylene on top of the base paper. However this kind of moisture-proof paper has a problem in recycling so that it brings about environmental pollution. In general the moisture-proof paper has been made by laminating polyethylene or polypropylene on top of the base paper. However this kind of moisture-proof paper has a problem in recycling so that it brings about environmental pollution. The purpose of this paper was to make moisture-proof paper using the mixture of SB latex and wax emulsion which was recyclable and environmentally friendly. Water vapor transmission rate showed less than 50g/$m^2$.24hr in mixture ratio of 85:15, 87:13, 90:10. Especially the mixture ratio of 87:13 showed the most favorable water-vapor transmission rate. However, the moisture-proof layer was destroyed slightly by folding in packing. It has been observed that there was no close relationship between water-vapor transmission rate of the moisture-proof paper and grammage of the base paper, but the density of base paper had influenced on water vapor transmission rate. It was also observed that the moisture-proof paper could be recycled. The moisture-proof paper was similar to base paper in degree of the pulping, and there was no significant difference in dispersion between moisture-proof paper and base paper. Most of wax particles which caused the spots during drying process could be removed by flotation process. Tensile strength and tear strength of both moisture-proof paper and base paper after pulping were measured to examine the fiber bonding, and no significant difference in physical properties was observed.

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Antibacterial and Antifungal Studies on Some Schiff Base Complexes of Zinc(II)

  • Joseyphus, R. Selwin;Nair, M. Sivasankaran
    • Mycobiology
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    • 제36권2호
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    • pp.93-98
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    • 2008
  • Two Schiff base ligands $L_1\;and\;L_2$ were obtained by the condensation of glycylglycine respectively with imidazole-2-carboxaldehyde and indole-3-carboxaldehyde and their complexes with Zn(II) were prepared and characterized by microanalytical, conductivity measurement, IR, UV-Vis., XRD and SEM. The molar conductance measurement indicates that the Zn(II) complexes are 1:1 electrolytes. The IR data demonstrate the tetradentate binding of $L_1$ and tridentate binding of $L_2$. The XRD data show that Zn(II) complexes with $L_1\;and\;L_2$ have the crystallite sizes of 53 and 61 nm respectively. The surface morphology of the complexes was studied using SEM. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species Staphylococcus aureus, Escherichia coli, Klebsiella pneumaniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by the disc diffusion method. A comparative study of inhibition values of the Schiff base ligands and their complexes indicates that the complexes exhibit higher antimicrobial activity than the free ligands. Zinc ions are proven to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium.

특허정보분석을 활용한 지식단위의 변화와 미래숙련수요 분석 - 이차전지 사례를 중심으로 (Analysis of Knowledge Base and Future Skills Needs through Patentometrics - Case of Battery Industry)

  • 황규희;심위;고병열
    • 기술혁신학회지
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    • 제14권spc호
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    • pp.1209-1231
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    • 2011
  • 본 연구에서는 기술전망과 특허분석에 기반하여 새로운 지식의 등장에 대한 미래숙련수요 분석방법론의 개발을 도모한다. 이차전지산업을 대상으로 하여 특허분류 기반 지식단위를 추출하고, 이러한 지식단위가 향후 이차전지 산업의 패러다임 전환에 대응하여 어떻게 변화하는가를 고찰하였다. 나아가 이에 기반하여 현행 관련 교과목에 대한 진단을 수행하고, 교과과목의 개선 필요사항을 제시하였다. 이러한 본 연구는 미래숙련수요 분석에 특허정보분석이 어떻게 활용될 수 있을지를 보임으로써, 특허 정보분석의 활용도를 높이는 한편 미래숙련수요 분석방법론의 진전을 도모하고자 하였다.

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Density Aware Energy Efficient Clustering Protocol for Normally Distributed Sensor Networks

  • Su, Xin;Choi, Dong-Min;Moh, Sang-Man;Chung, Il-Yong
    • 한국멀티미디어학회논문지
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    • 제13권6호
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    • pp.911-923
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    • 2010
  • In wireless sensor networks (WSNs), cluster based data routing protocols have the advantages of reducing energy consumption and link maintenance cost. Unfortunately, most of clustering protocols have been designed for uniformly distributed sensor networks. However, some urgent situations do not allow thousands of sensor nodes being deployed uniformly. For example, air vehicles or balloons may take the responsibility for deploying sensor nodes hence leading a normally distributed topology. In order to improve energy efficiency in such sensor networks, in this paper, we propose a new cluster formation algorithm named DAEEC (Density Aware Energy-Efficient Clustering). In this algorithm, we define two kinds of clusters: Low Density (LD) clusters and High Density (HD) clusters. They are determined by the number of nodes participated in one cluster. During the data routing period, the HD clusters help the neighbor LD clusters to forward the sensed data to the central base station. Thus, DAEEC can distribute the energy dissipation evenly among all sensor nodes by considering the deployment density to improve network lifetime and average energy savings. Moreover, because the HD clusters are densely deployed they can work in a manner of our former algorithm EEVAR (Energy Efficient Variable Area Routing Protocol) to save energy. According to the performance analysis result, DAEEC outperforms the conventional data routing schemes in terms of energy consumption and network lifetime.

슬롯의 점적률을 고려한 교류발전기의 출력밀도 개선 (Implement of Power Density for AC Generator Using a Fill Factor of Slot)

  • 이재원;김영길
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2017년도 춘계학술대회
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    • pp.275-278
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    • 2017
  • 차량의 교류발전기는 성능 및 효율에 따라 자동차의 연비와 배기가스에 많은 영향을 준다. 효율을 개선시키고 연비를 향상시키려는 노력은 자동차업체및 업체를 중심으로 계속되고 있다. 본논문은 A교류 발전기의 설계절차를 정리하고 같은 크기의 교류발전기에서 출력을 최적화하는 인자를 발굴하여 실차의 조건에서 충방전 Simulation을 통해 Energy Balance를 검증하였다.

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나노 $BaTiO_3$ 수계슬러리에서 미세구조 및 전기적 특성에 미치는 $Ba^{2+}$이온 용출의 영향 (The Effect of $Ba^{2+}$ion Dissolution on Microstructural Changes and Electrical Properties in $BaTiO_3$ Aqueous Slurry System)

  • 김상우;신용욱;이해원;윤기현
    • 한국세라믹학회지
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    • 제37권5호
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    • pp.511-515
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    • 2000
  • The effect of Ba2+ ion dissolution with different pH and amount of PAA on microstructural changes of green and sintered bodies and its electrical properties was studied in aqueous nano-size BaTiO3 slurry system. The dissolution of Ba2+ was least at strong base, pH 10.8 and by addition of amount of 0.15 wt% PAA. The green body with the lowest of dissolution of Ba2+ at pH 10.8 and 0.15 wt% PAA had minimum values of average pore size, 40nm and shown high increase of sintered density. The compact sintered at 125$0^{\circ}C$ for 2 hr with highest Ba2+ dissolution had low density and dielectric constant due to abnormal grian growth. However, the sintered body with the lowest Ba2+ dissolution had high sintered density and then shown high dielectric constant.

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The Stability of Plating Solution and the Current Density Characteristics of the Sn-Ag Plating for the Wafer Bumping

  • Kim, Dong-Hyun;Lee, Seong-Jun
    • 한국표면공학회지
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    • 제50권3호
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    • pp.155-163
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    • 2017
  • In this study, the effects of the concentration of metal ions and the applied current density in the Sn-Ag plating solutions were examined in regards to the resulting composition and morphology of the solder bumps' surface. Furthermore the effect of any impurities present in the methanesulfonic acid used as a base acid in the Sn-Ag solder plating solution on the stability of plating solution as well as the characteristics of the Sn-Ag alloys films was also explored. As expected, the uniform bump was obtained by means of removing impurities in the plating solution. Consequently the resultant solder bump was obtained in an optimal current density of the range of $1A/dm^2$ to $15A/dm^2$, which has acceptable bump shape and surface roughness with 12inch wafer trial results.

YAG LASER에 의한공구강의 표면개질에 관한 연구 (A Study on the Surfaces Modification of Tool Steel by YAG LASER)

  • 강형식
    • 한국생산제조학회지
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    • 제9권2호
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    • pp.66-71
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    • 2000
  • Laser induced surface hardening of Tool steel(STC5) can be achieved either with or without surface melting. In trans-formation hardening as the surface is heated to a temperature below its melting point and is rapidly cooled solidified microstructures are usually much finer and stronger than those of the base matals. For this reason surface modification of tool steel by YAG laser irradiation has been studied as a function of processing parameters such as power density pulse width defocusing distance and molten depth. The high energy density changes and refines the microstructure of the near surface layer. In the case of beam passes martensite formed in the melt zone exhibited very high vickers hardness values. Molten depth and width depend on defocusing distance and energy of black color painting is more absorptive than other color painting.

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