• 제목/요약/키워드: seed point

검색결과 179건 처리시간 0.033초

대체연료를 사용할 경우의 디젤기관의 성능향상에 관한 연구 (Improvement of Diesel Engine Performance for Alternative Fuel Oil)

  • 고장권
    • Journal of Advanced Marine Engineering and Technology
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    • 제16권5호
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    • pp.97-110
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    • 1992
  • Rape-seed oil has high viscosity and high rubber content like other vegetable oils. When crude rape-seed oil obtained by a general oil extraction process is used in a diesel engine, automization condition during injection is not good and a large amount of combustion product is doposited in a combustion chamber. The improvement of a diesel engine is required to use rape-seed oil as a diesel engine fuel. In this study, the physical and chemical properties and combustion characteristics of rape-seed oil were investigated. The auxiliary aid was developed to improve automization condition and the effect of the auxiliary injection aid on the performance of a diesel engine was determined. The results are as follows. 1) Oil content of rape-seed is 45%. The exraction rate is 33%. The resuls show higher values compared to those of other vegetable oils. 2) The viscosity of rape-seed oil is 50.8 cSt and nearly 14 times of diesel oil viscosity. 3) The heating value and flash point of rape-seed oil are 9720kcal/Kg and 318$^{\circ}C$, respectively. 4) In case rape-seed oil is used as fuel, brake horse power, specific fuel consumption and brake thermal efficiency are compared to those of diesel oil. The results of rape-seed oil show 3.6%, 12.7% and 3.1% higher values. 5) Particle size of injection fuel with the auxiliary injection aid on the performance of a diesel engine was determined. The results are as follows. 1) Oil content of rape-seed is 45%. The extraction rate is 33%. The results show higher values compared to those of other vegetable oils. 2) The viscosity of rape-seed oil is 50.8 cSt and nearly 14 times of diesel oil viscosity. 3) The heating value and flash point of rape-seed oil are 9720kcal/Kg and 318.deg.C, respectively. 4) In case rape-seed oil is used as fuel, brake horse power, specific fuel consumption and brake thermal efficiency are compared to theose of diesel oil. The results of rape-seed oil show 3.6%, 12.7% and 3.1% higher values. 5) Particle size of injection fuel with the auxiliary injection aids is 100.mu.m smaller than that od injection fuel without the aid. 6) Brake horse power and brake thermal efficiency with the auxiliary injection aid increase 5.07% and 6.07%, respectively. However, specific fuel consumption decreases 3.85% with the auxiliary injection aid.

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Cu Seed Layer의 열처리에 따른 전해동도금 전착속도 개선 (Improvement of Electrodeposition Rate of Cu Layer by Heat Treatment of Electroless Cu Seed Layer)

  • 권병국;신동명;김형국;황윤회
    • 한국재료학회지
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    • 제24권4호
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    • pp.186-193
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    • 2014
  • A thin Cu seed layer for electroplating has been employed for decades in the miniaturization and integration of printed circuit board (PCB), however many problems are still caused by the thin Cu seed layer, e.g., open circuit faults in PCB, dimple defects, low conductivity, and etc. Here, we studied the effect of heat treatment of the thin Cu seed layer on the deposition rate of electroplated Cu. We investigated the heat-treatment effect on the crystallite size, morphology, electrical properties, and electrodeposition thickness by X-ray diffraction (XRD), atomic force microscope (AFM), four point probe (FPP), and scanning electron microscope (SEM) measurements, respectively. The results showed that post heat treatment of the thin Cu seed layer could improve surface roughness as well as electrical conductivity. Moreover, the deposition rate of electroplated Cu was improved about 148% by heat treatment of the Cu seed layer, indicating that the enhanced electrical conductivity and surface roughness accelerated the formation of Cu nuclei during electroplating. We also confirmed that the electrodeposition rate in the via filling process was also accelerated by heat-treating the Cu seed layer.

기존 건축물의 녹색건축인증 개선방향에 대한 연구 (A Study on Improvement Direction of G-SEED for Existing Buildings)

  • 현은미;이재은;안광호
    • 대한건축학회논문집:구조계
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    • 제34권5호
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    • pp.59-67
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    • 2018
  • G-SEED's evaluation of existing buildings is an important point because the energy consumption and CO2 emissions of existing buildings are continuously increasing due to the aging of buildings over time. However, as G-SEED certification is concentrated on new buildings and the standards are not yet available, we will make improvements to evaluate the existing buildings of G-SEED. In order to improve G-SEED for EB, two research procedures were carried out. First, LEED EBOM and LEED for NC compare and analyze evaluation items and methods, and LEED EBOM focuses on evaluation of existing buildings. Second, we analyzed the certification evaluation contents of eight domestic LEED EBOM accredited buildings and obtained items that can be applied or need to be applied when revising G-SEED for EB. LEED EBOM is focused on improving the performance and utilization of data that track and manage the energy and environmental effects of building operations. As a result of the case analysis, the evaluation of G-SEED for EB requires quantitative evaluation items such as environmental management of buildings, energy performance status of building, improvement plan and improvement of performance according to tracking value. Although G-SEED for EB is not structured yet and there are few cases of certification, it is expected that quantitative evaluation of existing buildings will be made through continuous research.

Seed 금속의 종류와 두께에 따른 구리 전착층의 표면형상에 미치는 영향 (Effect of Kind and Thickness of Seed Metal on the Surface Morphology of Copper Foil)

  • 우태규;박일송;설경원
    • 한국재료학회지
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    • 제17권5호
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    • pp.283-288
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    • 2007
  • This study aimed to investigate the effects of the seed layer with copper electroplating on the surface morphology of copper foil. Three kinds of seed metal such as platinum, palladium, Pt-Pd alloy were used in this study. Electrodeposition was carried out with the constant current density of 200 $mA/cm^2$ for 68 seconds. Electrochemical experiments, in conjunction with SEM, XRD, AFM and four-point probe, were performed to characterize the morphology and mechanical characteristics of copper foil. Large particles were observed on the surface of the copper deposition layer when a copper foil was electroplated on the 130 nm thickness of Pd, Pt-Pd seed layer. However, a homogeneous surface, low resistivity was obtained when the 260 nm thickness of Pt, Pt-Pd alloy seed layer was used. The minimum value of resistivity was 2.216 ${\mu}{\Omega}-cm$ at the 260 nm thickness of Pt-Pd seed layer.

Fabrication of a large grain YBCO bulk superconductor by homo-seeding melt growth method

  • Lee, Hee-Gyoun
    • 한국초전도ㆍ저온공학회논문지
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    • 제24권3호
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    • pp.35-40
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    • 2022
  • To fabricate large grain YBCO bulk superconductors by melt process, Sm123 single crystal with a high melting point are mostly used as seeds. However, it also uses Y123 film deposited on MgO single crystal substrate. This study investigated the growth behavior of the Y123 grain during a melt process when single grain YBCO bulk was used as a seed. Single grain Y123 bulk was grown when the seed size was small. When the seed size was relatively large, multiple grains were grown but the grains were still large. Y123 seed crystal was completely decomposed during high temperature anneal at 1040℃ and new Y123 crystals were nucleated during a slow cooling stage below a peritectic temperature. Thereafter, newly formed Y123 crystals from the seed area are thought to grow into the Y1.8 powder compact. The crystallographic orientations of newly nucleated Y123 grains are independent of the crystallographic orientation of Y123 seed. It is thought that the crystallographic orientation of newly nucleated Y123 crystal can be controlled by using Y211-free Y123 single crystal as a seed of homo-seeding melt growth.

Varietal Difference of Dry Matter Production and Photosynthetic of Middle and Lower Leaves in Soybean

  • Cho, Jin-Woong;Kim, Choong-Soo;So, Jung D.
    • 한국작물학회지
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    • 제48권1호
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    • pp.25-30
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    • 2003
  • This research was conducted to compare the dry matter production and the yield productivity among nine soybean cultivars by measuring the photosynthetic ability of the middle and lower leaves at the flowering and the seed development stages. The leaf greenness(SPAD value) were ranged as 32-42 at the flowering stage. Also, They were ranged as 25-40 and 38-51 at the fifth leaf and the seventh leaf, respectively. The photosynthetic ability at the flowering and the seed development stage showed significant differences among soybean cultivars, and the photosynthetic ability at the seed development stage showed higher difference among cultivars than the flowering stage. The variation of the photosynthetic ability at the flowering and the seed development stage also was significant among cultivars. The light saturation point at the flowering stage was about 1500 $\mu$mol $m^{-2}$ $s^{-1}$ PAR, and the seed development stage was about 1000 $\mu$mol $m^{-2}$ $s^{-1}$ PAR. The photosynthesis showed the high negative correlation with the leaf area and the positive correlation with the leaf area ratio. Also, photosynthesis at seed development stage showed positive correlation with grain yields but there was not significant between photosynthesis and yields at flowering stage..

분리 동백단백의 기능적 특성 (A Study on the Functional Properties of Camellia(Camellia japonica L.) Seed Protein Isolate)

  • 강성구
    • 한국자원식물학회지
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    • 제11권3호
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    • pp.272-278
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    • 1998
  • This study was carried out to investigate the functional properties such as nitrogen solubility, emulsifying property , foaming capapcity , water and oil absorption of Camellia (Camellia japonica .) seed protein isolate in condition of distilled water and 0.5M NaCl solution at pH 2.0∼10.0. Nitrogen solubility of Camellia protein isolate in distilled water showed the minimum value at pH 4.0 and increased at pH lower or higher than the isoelectric point(pH 4.0). It was 90.0 %at pH 10.0 Nitrogen solubility of 0.5M NaCl solution showed a similar pattern with that of distrille dwater but was higher than that of distilled water except pH 2.0 and pH 10.0. Emulsifying activity of Camellia seed protein islate showed the minimum value at pH 4.0, but was higher at ether value of pH. Emulsifying stability of protein isolate was stable by heat treatment for 30min, at 80℃ and increased in 0.5M NaCl solution more than that of distille dwater. Foaming capacity of Camellia seed protein isolate in distill3ed water showed the minimum value near the isoelectric point, While it changed little at other values of pH. Foaming stability slowly decreased as, but didn't make a significant difference as time was delayed . Oil absorption was 1.4ml per a sample of 1g and water absorption was 0.9ml per a sample of 1g. The former was higher than the latter . The content of total amino acid of Camellia protein isolate was 43.67% and the major total amino acid of Camellia protein isolate was 43.67% and the major total amino acid was in the order of glutamic acid , arginine, aspartic acid, and leucine.

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MODIFIED DOUBLE SNAKE ALGORITHM FOR ROAD FEATURE UPDATING OF DIGITAL MAPS USING QUICKBIRD IMAGERY

  • Choi, Jae-Wan;Kim, Hye-Jin;Byun, Young-Gi;Han, You-Kyung;Kim, Yong-Il
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.234-237
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    • 2007
  • Road networks are important geospatial databases for various GIS (Geographic Information System) applications. Road digital maps may contain geometric spatial errors due to human and scanning errors, but manually updating roads information is time consuming. In this paper, we developed a new road features updating methodology using from multispectral high-resolution satellite image and pre-existing vector map. The approach is based on initial seed point generation using line segment matching and a modified double snake algorithm. Firstly, we conducted line segment matching between the road vector data and the edges of image obtained by Canny operator. Then, the translated road data was used to initialize the seed points of the double snake model in order to refine the updating of road features. The double snake algorithm is composed of two open snake models which are evolving jointly to keep a parallel between them. In the proposed algorithm, a new energy term was added which behaved as a constraint. It forced the snake nodes not to be out of potential road pixels in multispectral image. The experiment was accomplished using a QuickBird pan-sharpened multispectral image and 1:5,000 digital road maps of Daejeon. We showed the feasibility of the approach by presenting results in this urban area.

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SEED 형식 암호에서 S 박스와 G 함수 구성에 관한 연구 (A study on the constitution of S box and G function in SEED-type cipher)

  • 송홍복;조경연
    • 한국통신학회논문지
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    • 제27권4A호
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    • pp.291-300
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    • 2002
  • 본 논문에서는 우리나라 128 비트 블록 암호 알고리즘 표준인 SEED와 유사한 구조를 가지는 암호방식에서 최적화한 S 박스와 G 함수를 구성하는 방식을 제안한다. S 박스는 비선형 함수와 아편변환으로 구성한다. 비선형함수는 차분공격과 선형공격에 강한 특성을 가지며, '0'과 '1'을 제외하고 입력과 출력이 같은 고정점과 출력이 입력의 1의 보수가 되는 역고정점을 가지지 않는 GF(2$^{8}$ ) 상의 역수로 구성한다. 아핀변환은 입력과 출력간의 상관을 최저로 하면서 고정점과 역고정점이 없도록 구성한다. G 함수는 4개의 S 박스 출력을 GF(2$_{8}$ ) 상의 4$\times$4 행렬식을 사용하여 확산선형변환한다. G 함수는 MDS(Maximum Distance Separable) 코드를 생성하구 SAC(Strict Avalanche Criterion)를 만족하고, 고정점과 역고정점 및 출력이 입력의 2의 보수가 되는 약한 입력이 없으며, 하드웨어 구현이 용이하도록 구성한다. 본 논문에서 제안한 S 박스와 G 함수는 차분공격과 선형공격에 강하고, 약한 입력이 없으며, 하드웨어 구현이 용이하며, 확산 특성이 우수하므로 안전성이 높은 암호 방식의 구성 요소로 활용할 수 있다.