• Title/Summary/Keyword: property change

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Optical, Thermal property by Applied PCB Structure design (PCB 구조적 설계에 따른 LED Module의 열적 광학적 특성)

  • Lee, Seung-Min;Lee, Seong-Jin;Choi, Gi-Seung;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2006.07d
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    • pp.2241-2242
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    • 2006
  • As developing the information society, Lighting Emitted diode(LED) which is light source for illumination of next generation is attracted public attention. LED have many problem as narrow light view angle, high price, drift phenomenon of color coordinate, high heating problem for lower power, lower weight and small size. So, many researches have continued in a illumination as LED module type. in this problem, heating problem is very important and difficult and that is caused in decreasing phenomenon of brightness and drift phenomenon of color coordinate. so the problem of heating is urgent question for illumination of LED. In this paper, structural design of PCB changed as two type for solving the heating problem. also the properties of heating is analysed and optical properties is measured with heating image camera and spectrometer according to change in this design.

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Frame resizing scheme in H.264/AVC compressed domain (H.264/AVC 압축 도메인에서의 프레임 resizing 방법)

  • Oh, Hyung-Suk;Kim, Won-Ha
    • Proceedings of the KIEE Conference
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    • 2006.10c
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    • pp.145-147
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    • 2006
  • Image resizing is to change an image size by upsampling or downsampling of a digital image. Most still images and video frames are given in a compressed domain on digital media. Image resizing of a compressed image can be performed in a spatial domain via decompression or recompression. In general, resizing of a compressed image in a compressed domain is much faster than that in a spatial domain. In this paper, we propose an approach to resize images in the integer discrete cosine transform (DCT) domain, which exploits the multiplication-convolution property of DCT.

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Effect of the Application of Several Organic Materials on Ginseng Growth (수종유말물 시용이 인삼생육에 미치는 영향)

  • 이일호;박찬수
    • Journal of Ginseng Research
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    • v.14 no.3
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    • pp.427-431
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    • 1990
  • To search for substituents of greens, several organic materials such as rice straw, barley straw, corn stem and manufactured compost were applied in a ginseng cultivating field. The yields of six year old ginseng harvested in the rice straw, barley strait and corn stem treated field were similar to or higher than that of the greens treated one. The varied amount of applied substituents resulted in a yield change, but statistical linearity was not found. The growth of ginseng aerial part and soil physicochemical property in the field fortified with these substituents showed similar results to those of the greens treated one. So, it is though that these organic materials can substitute for greens.

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Molecular Dynamics Study on Property Change of CMP Process by Pad Hardness (CMP 공정에서 연마패드 경도에 따른 연마 특성 변화 분자동력학 연구)

  • Kwon, Oh Kuen;Choi, Tae Ho;Lee, Jun Ha
    • Journal of the Semiconductor & Display Technology
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    • v.12 no.1
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    • pp.61-65
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    • 2013
  • We investigated the wearable dynamics of diamond spherical abrasive during the substrate surface polishing under the pad compression via classical molecular dynamics modeling. We performed three-dimensional molecular dynamics simulations using the Morse potential functions for the copper substrate and the Tersoff potential function for the diamond abrasive. The pad hardness had a big impact on the wearable dynamics of the abrasive. The moving speed of the abrasive decreased with increasing hardness of the pad. As the hardness decreased, the abrasive was indented into the pad and then the sliding motion of the abrasive was increased. So the pad hardness was greatly influenced on the slide-to-roll ratio as well as the wearable rate.

A Study for Mechanical and Platelet Adhesion Properties of Fluorinated Polyurethanes (불소화된 폴리우레탄의 기계적 물성과 혈소판 점착특성에 관한 연구)

  • 김형중
    • Polymer(Korea)
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    • v.25 no.3
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    • pp.343-348
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    • 2001
  • The mechanical and the platelet adhesion properties of the fluorinated polyurethane elastomers synthesized with a perfluorinated polyether diol (Fomblin ZDOL$ZDOL^{(R)}$) and 4,4'-diphenyl methane diisocyanate (MDI) were investigated. The change of mechanical properties with the Fomblin content and the type of the polyether diol was investigated by applying a designed technique using in vitro platelet adhesion test. As a result, the tensile properties were affected by the content and the type of nixed polyether diols. Also the platelet adhesion of polyurethane elastomers decreased with increasing the extent of fluorination in the polymer.

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Hematological Changes in Dogs Administrated Excessive Amount of Water Celery Concentrated extract (농축 미나리 추출물의 투여가 개의 혈액상에 미치는 영향)

  • 김홍태;장혜숙;안병만;김영홍;오태호
    • Journal of Veterinary Clinics
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    • v.18 no.2
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    • pp.111-115
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    • 2001
  • The water celery, Oenanthe javanica DC., is widely distributed in Korea and the other South East Asian countries. From ancient times, the water celery has widely been used for food or medicine. In herbal medicine, the water celery has a medical actions which are defervescence, diuresis, hypotensor, appetizer. Recently, studies on the water celery are briskly being conducted. For example, studies on the morphologic property and classifications of origin of the water celery, studies on the chemical constituents of the Water celery, studies on the bio activities of the water celery which contains flavonoids. However, there is not studies of hematological changes in dogs administrated the water celery until now. Consicontly, this study was conducted to observe the hematological changes in dogs administrated excessive amount of the water celery concentrated extract for a long period. In this studies, all dogs showed significantly decrease of the RBC, PCV, Hb and MCHC, and increase of the WBC, MCV, GSH and reticulocytes, but did not significantly change in the Met-Hb.

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Characteristics of Commercial Celluloytic Enzymes (상업용 목질섬유소 분해 효소의 특성)

  • Kim, Young-Yuk;Kim, Chul-Hyun;Park, Soung-Bae;Eom, Tae-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.36 no.3
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    • pp.1-8
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    • 2004
  • It is very difficult to compare directly the research results of enzymatic process in pulp and paper industry because commercial enzymes have diversity in its property. The chemical and biological properties of commercial enzymes were Investigated to help comparison of various commercial enzymes each other. In most case, the solid content of liquid enzymes was about 20%. The higher protein content in enzyme product does not mean the higher enzyme activity. Enzymes for paper process should selected by basis of enzyme activity, not by price of enzyme products. The chemical composition of fiber was not so much change with enzyme treatment. The enzymatic hydrolysis of fiber might negligible in paper process.

Proposal of the Stress Wave Concept and Its Applied Study as a Theory for the Dislocation Formation (전위생성에 대한 이론으로서의 응력파 개념에 대한 제안 및 적용 연구)

  • 서정현
    • Transactions of Materials Processing
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    • v.10 no.6
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    • pp.449-456
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    • 2001
  • The concept of stress wave was introduced through the quantized kinetic energy which is related to the potentional energy change of atom, molecular bond energy. Differentiated molecular bond energy $\varphi$() by the lst order displacement u becomes force F(F = d$\varphi$($u_i$)/du), if resversely stated, causing physically atomic displacement $u_i$. Such physical phenomena lead stress(force/area of applied force) can be expressed by wave equation of linearly quantized physical property. Through the stress wave concept, formation of dislocation, which could not explained easily from a theory of continuum mechanics, can be explained. Moreover, this linearly quantized stress wave equation with a stress concept for grains in a crystalline solid was applied to three typical metallic microstructures and a simple shape. The result appears to be a product from well treated equations of a quantized stress wave. From this result, it can be expected to answer the reason why the defect free and very fine diameters of long crystalline shapes exhibit ideal tensile strength of materials.

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A Study on Fair Competition Forms under the Electronic Commerce of the New Competition Forms (저자상거래에서 신 경쟁형태에 따른 공정경쟁에 관한 연구)

  • Kang Lee-Soo
    • Journal of Arbitration Studies
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    • v.15 no.1
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    • pp.179-206
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    • 2005
  • The development of information & telecommunication technology and internet-based electronic commerce helps to create a new economic environment. Such an economic environment requires the companies to change themselves, while providing unlimited potential and opportunities to them. Thus, in order to help the companies engaged in a fair and free competition in the electronic market, a fair competition policy needs to be designed and operated. The electronic commerce has not only promote the competition but also impede it. The electronic commerces tend to violate the fair trade than the conventional commerces in terms of differentiation, monopoly, conference, limited competition and intellectual property rights, schumpeterian competition, Alliance competition. With such basic concepts in mind, this study was aimed at reviewing the economic effects of the electronic commerce in the market and addressing the problems involving the application of the fair trade code to the electronic commerce, and thereby, suggesting the insights into our fair competition policy and reform measures.

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Metal/ceramic Interface Mechanical Property Analysis (금속/세라믹 계면 물성 분석)

  • Kim, Song-Hee;Kang, Hyung-Suk
    • Journal of Industrial Technology
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    • v.24 no.A
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    • pp.9-15
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    • 2004
  • The flexural strength from 3-point bend test and fatigue properties were measured to evaluate mechanical properties of metal/ceramic interface of the multilayer ceramic package produced through tape casting. From the results, the specimens with three electrode layers showed the highest strength. The temperature distribution with time during thermal cycle and thermal stresses with the change of electrode's shape have been estimated by mathematical modelling. Specimen affected by thermal shock, produced microcracks by the difference of thermal expansion coefficient. The results of tensile test and fatigue test showed the rupture at pin. The fact that the pin brazed specimens were always fractured at the pin proved the good bonding condition between pin and electrode.

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