• Title/Summary/Keyword: History of research

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Influence of Density and Feeding Frequency on Early Life History and Cannibalism of River Puffer, Takifugu obscurus (황복, Takifugu obscurus의 초기 생활사와 공식 행위에 있어 밀도와 먹이 공급 횟수의 영향)

  • Kang, Duk-Young;Kim, Hyo-Chan;Kang, Hee-Woong
    • Development and Reproduction
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    • v.15 no.2
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    • pp.77-85
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    • 2011
  • To investigate the influence of density and feeding frequency (food amount) on growth, cannibal dynamics and survival of puffer Takifugu obscurus (TL $25.0{\pm}0.5$ mm, BW $0.53{\pm}0.03$ g) during early life history, we conducted one experiment composed with 6 density groups set up as 1.43 inds./${\ell}$, 2.14 inds./${\ell}$, 2.86 inds./${\ell}$, 3.57 inds./${\ell}$, 4.29 inds./${\ell}$ and 7.14 inds./${\ell}$. The experiment was triplicately performed in 1 ton FRP tank for 30 days. Daily food intake (DFI), feed efficiency (FE), growth, cannibal frequency, and survival rates were examined. Although not find any significant relation of density to DFI and FE, we found that growth decreased significantly with the increasing of density under 3.57 inds./${\ell}$, but significantly increased with the increasing of density over 4.29 inds./${\ell}$. Cannibal frequency and daily mortality rate was significantly increased with increasing density and decreasing feeding frequency, inducing the most poor survival rate in the highest density group and low feeding frequency. Therefore, we concluded that the density and the feeding frequencies affect sibling cannibal dynamics and survival of puffer stock.

Broadcast Content Recommender System based on User's Viewing History (사용자 소비이력기반 방송 콘텐츠 추천 시스템)

  • Oh, Soo-Young;Oh, Yeon-Hee;Han, Sung-Hee;Kim, Hee-Jung
    • Journal of Broadcast Engineering
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    • v.17 no.1
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    • pp.129-139
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    • 2012
  • This paper introduces a recommender system that is to recommend broadcast content. Our recommender system uses user's viewing history for personalized recommendations. Broadcast contents has unique characteristics as compared with books, musics and movies. There are two types of broadcast content, a series program and an episode program. The series program is comprised of several programs that deal with the same topic or story. Meanwhile, the episode program covers a variety of topics. Each program of those has different topic in general. Therefore, our recommender system recommends TV programs to users according to the type of broadcast content. The recommendations in this system are based on user's viewing history that is used to calculate content similarity between contents. Content similarity is calculated by exploiting collaborative filtering algorithm. Our recommender system uses java sparse array structure and performs memory-based processing. And then the results of processing are stored as an index structure. Our recommender system provides recommendation items through OPEN APIs that utilize the HTTP Protocol. Finally, this paper introduces the implementation of our recommender system and our web demo.

Image Matching with Characteristic Information of Gray Value and Interest Points

  • Lee, Dong-Cheon;Yom, Jae-Hong;Choi, Sun-Ok;Kim, Su-Jeong
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1467-1469
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    • 2003
  • Image matching is fundamental process to identify conjugate points on the stereo images. However, standard methods or general solutions for matching problem have not been found yet, in spite of long history. Quality of the matching basically depends on uniqueness of the matching entity and robustness of the algorithm. In this study, conjugate points were extracted by implementing interest operator, then area based matching method was applied to the topographical characteristics of the gray value as the matching entities. The matching entities were utilized based on the concept of the intrinsic image.

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Metallurgical Study of Iron Artifacts Yangju-Mountain Fortress (양주 대모산성 출토 철기유물의 금속학적 연구)

  • Lim, Sun-Ki;Kang, Dai-Ill;Moon, Whan-Suk;Park, Dong-Kyu;Kang, Sung-Goon
    • 보존과학연구
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    • s.14
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    • pp.1-34
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    • 1993
  • 1. Metallurgical Properties of Iron artifacts excavated from Yangju-Mountain fortress were studied for the scientific conservation and metallurgical history of ancient Iron artifacts.2. Iron artifacts form Yangju-Mountain fortress were found to be the products of having well-established Carburizing and remelting technique in that period.3. These artifacts seem to be manufactured from very pure ores, because very pure ferrite structure and low impurity.4. Especially evidence of very suitable carburizing technic well-established and usealloying method of Fe-C system on purpose were found.5. Cast iron artifacts were found to be eutectic composition (4.31%) having lowestmelting point in Fe-C system.

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SHANGHAI INSTITUTE OF METALLURGY--FACING THE WORLD

  • He, L.;Fu, L.P.
    • Journal of the Korean Vacuum Society
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    • v.4 no.S2
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    • pp.20-23
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    • 1995
  • Shanghai Institute of Metallurgy(SIM), Chinese Academy of Sciences is a multioriented applied science reaearch institution that was founded in 1928. The current principal research activities of SIM cover three areas, namely, microelecronics, functional materials and devices, corrosion and protection of metals. The general information of SIM, includes history, personnel, organization, etc., is provided. The main research laboratories and R&D themes are introduced also. SIM has made great contributions to the economic construction and development of science and technoloty of the nation. China is facing a golden opportunity for development and SIM is playing an important role in translating research results into large-scale, commercial productions. Several successful examples are shown. SIM has been active in promoting international collaboration in research and development. The international cooperative projects in SIM are reviewed. SIM is facing the world, and going toward the 21st century.

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한국동물학회 해외 과학자 초청 학술대회 초록: 1. Environmental Pollution and Cancer

  • Lee, Insu P.
    • The Korean Journal of Zoology
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    • v.26 no.4
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    • pp.295-296
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    • 1983
  • Further research needs in environmental carcinogenesis are much to be desired. Currently, the methodology for identification, quantitation, and assay of some environmental carcinogens is available, but there remains a pressing need for additional fundamental knowledge of the carcinogenic process at the molecular level. The best hope for the control of cancer lies in prevention and chemotherapy, and this in turn depends upon the generation of basic information not yet available. The history of medical science reveals that quantum advances in control and prevention of disease have been direct consequences of research applications derived from pools of existing knowledge. It is hoped that the major efforts on specific problems of eivironmental carcinogenesis and substantial support of research to obtain new knowledge will prove to be equally rewarding.

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First record of four bee (Hymenoptera: Apidae) associated mite species (Acari) from Democratic People's Republic of Korea

  • Kontschan, Jeno;Jeon, Mi Jeong;Hwang, Jeong Mi;Seo, Hong Yul
    • Journal of Species Research
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    • v.5 no.1
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    • pp.27-30
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    • 2016
  • Four mite species (Acari: Scutacaridae: Scutacarus acarorum (Goeze, 1780), Chaetodactylidae: Sennertia alfkeni (Oudemans, 1900); Ascidae: Proctolaelaps longanalis (Westerboer, 1963), Laelapidae: Hypoaspis (Pneumolaelaps) marginepilosa (Sellnick, 1938) are found on the body of bees deposited in the Hungarian Natural History Museum, Budapest. The host bee species were collect in Democratic People's Republic of Korea; the found four species are collected at first time in Democratic People's Republic of Korea.

Grain-Size Distribution of Source Areas of Asian Dust (Yellow Sand) in China

  • Yi, Hi-Il;Shin, Im-Chul
    • The Korean Journal of Quaternary Research
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    • v.21 no.2
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    • pp.77-79
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    • 2007
  • The source regions of Asian Dusts (Yellow Sands) in the western part of China are investigated, and the soil samples are collected samples for approximately 15 days during the spring of 2005. Particle sizes of sediments are analyzed and compared with each other. These grain-size analyses from the source areas can be compared Particle sizes between loess deposits and desert sands in western part of China and desert areas show distinctive differences. Loess deposits are predominantly composed of fine sands and silts. The distinction between the final characteristics of Asian Dust particles arrived in Korea and characteristics during transportation can be recognized comparison with the Asian Dust particles collected where the dust particles settled down. The characteristics of Asian Dust particle sizes can provide the basic information regarding the transportation history from the source region.

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Evaluating Internet Pricing Schemes: A Three-Dimensional Visual Model

  • Nguyen, Thuy T.T.;Armitage, Grenville J.
    • ETRI Journal
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    • v.27 no.1
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    • pp.64-74
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    • 2005
  • Traditional Internet pricing schemes are coming under continual pressure to adapt to, and encourage, a changing mix of Internet applications and consumer usage patterns. Much research effort over the last decade has been focused on developing more efficient and attractive charging schemes. However, none of the proposed models has been widely deployed. This raises questions regarding the inhibiting factors and missing pieces that make pricing the Internet such a challenge. In this paper, we discuss the problems with current Internet pricing schemes, review the history of Internet pricing research over the last ten years, and summarize the key features and motivations of the most significant models. We develop a novel visual approach to comparing and evaluating such schemes using a three-dimensional (3D) metric encompassing technical efficiency, economic efficiency, and social impact. We address and discuss the important factors that have inhibited the deployment of the reviewed models and suggest productive areas of focus for future Internet pricing research.

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Nailbed malignant melanoma in three dogs

  • Jo, Hyoung-Nam;Suh, Myeong-Won;Lee, Joo-Ok;Kim, Jae-Hoon
    • Korean Journal of Veterinary Research
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    • v.59 no.4
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    • pp.219-222
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    • 2019
  • Three 8-12-year-old male cocker spaniels presented with an appendicular mass accompanied by pain, inflammation, lameness, and loss of nail in the digits of the forelimb or hindlimb. A histological examination revealed dermal masses of the digit composed of numerous neoplastic cells with marked pleomorphism and high mitosis. The neoplastic cells showed a strong invasive tendency into the epidermis and adjacent bony tissues, such as distal phalanx. Immunohistochemistry of the neoplastic cells in three masses revealed positive reactions for Melan-A. These three dogs were diagnosed as nailbed malignant melanoma in the digit based on the history, clinical signs, and histopathologic features.