• Title/Summary/Keyword: light elements

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First records of Hemicyclops tanakai Itoh and Nishida, 2002 and Tisbe ensifer Fischer, 1860 (Crustacea, Copepoda) in Korea

  • Karanovic, Tomislav;Lee, Wonchoel
    • Journal of Species Research
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    • v.5 no.3
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    • pp.289-299
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    • 2016
  • Extensive survey of invertebrates in Korea, led by the National Institute of Biological Resources in Incheon, continues to uncover many new and endemic species, but also elements of neighbouring faunas that were previously unknown here. Hemicyclops tanakai Itoh and Nishida, 2002 was originally described from estuarine mud-flats in Tokyo Bay, Japan. We report one male and two females from a sandy beach on Jeju Island, which represent its first record in Korea and second record ever. No morphological differences were observed between these two disjunct populations, so we expect more records of this species in Korea and Japan. Tisbe ensifer Fischer, 1860 was originally described from Madeira and later on reported from numerous other parts of the Northern Atlantic, as well as from the Indian Ocean. We report two females from a shallow littoral in Sokcho, which represents its first record in Korea and the first record in the entire Pacific Ocean. Because of morphological discrepancies reported in previous records we recognize that this species might be in reality a species complex, and we only tentatively identify our Korean specimens as T. cf. ensifer. We provide numerous light photographs of both species in addition to short descriptions, in hope that they might elucidate global problems of their zoogeography and dispersal of small marine invertebrates in general. Further samplings from Korea and other parts of the world will be necessary to test our identifications and phylogenetic relationships of Korean populations with molecular and other tools.

Study on the Performance of Laser Welded joint of Aluminum alloys for Car Body

  • Kutsuna, Muneharu;Kitamura, Shuhei;Shibata, Kimihiro;Salamoto, Hiroki;Tsushima, Kenji
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.620-625
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    • 2002
  • Considering the fuel consumption of car, a light structure of aluminum alloys is desired for car body nowadays. However, fusion welding of aluminum alloys has some problems of reduction of joint efficiency, porosity formation and hot cracking. ill the present work, investigation to improve the joint performance of laser welded joint has been carried out by addition of Cu, Ni, and Zr to A6N01 alloy welds. Aluminum alloy plate of 2.0mm in thickness with filler metal bar was welded by twin beam Nd:YAG laser facility (total power:5kW). The filler metals were prepared by changing the chemical compositions for adding the elements into the weld metal. Thirteen filler metal bars were prepared and pre-placed into the base metal before welding. Ar gas shielding with a flow rate of 10 l/min was used. The defocusing distance is kept at 0 mm. At travel speeds of 3 to 9 m/min and at laser power of 5kW (front beam 2kW rear beam 3kW), full penetration welds were obtained, whereas at travel speeds of 12 to 18 m/min and same power, partial penetration was observed. The joint efficiency of laser-welded joint was improved by the addition of Cu, Ni, and Zr due to the solid solution hardening, grain refining and precipitation hardening. The type of hardening has been further considered by metallurgical examination.

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Deducing environmentally conscious factors for apartment complex planning and weight evaluation (환경요소를 고려한 공동주택 단지계획요소 도출 및 가중치 평가)

  • Jung, Suk-Jin;Seo, Jung-Bum;Yoon, Seong-Hwan
    • KIEAE Journal
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    • v.16 no.6
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    • pp.51-56
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    • 2016
  • Purpose: As declines in the quality of residential environments occur, such as urban heat island effect, tropical night phenomenon, and violations of right to light and privacy due to urban densification and high rise building, these problems are emerging as social issues. In order to improve these issues, design factors which consider environmental aspects must be selected when planning apartment complexes, and ways to reflect them in the planning phase must be explored. Method: In this study, the analytical hierarchy process(AHP) was used to deduce design factors that considered environmental elements during the planning of apartment complexes. Furthermore, the priority and weight for each evaluation index were assessed. The objective was to propose a guideline for planning apartment complexes by finding the best solution for each evaluation index using complex weight values. Result: Floor area ratio was selected as the most important evaluation criterion in the environmentally conscious evaluation index for apartment complex planning. The shape and placement of skylights were selected as the most important evaluation criteria in the sunshine environment for a pleasant residential environment. Ground surface cover design was selected as the most important criterion in the outdoor thermal environment index for improving the microclimate within cities and apartment complexes. Thus, the results of this study can serve as an investigation guideline that concerns policy and regulations, and as reference data that can be used in planning apartment complexes.

Side Channel Attacks on HIGHT and Its Countermeasures (HIGHT에 대한 부채널 분석 및 대응 방법)

  • Kim, Tae-Jong;Won, Yoo-Seung;Park, Jin-Hak;An, Hyun-Jin;Han, Dong-Guk
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.25 no.2
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    • pp.457-465
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    • 2015
  • Internet of Things(IoT) technologies should be able to communication with various embedded platforms. We will need to select an appropriate cryptographic algorithm in various embedded environments because we should consider security elements in IoT communications. Therefore the lightweight block cryptographic algorithm is essential for secure communication between these kinds of embedded platforms. However, the lightweight block cryptographic algorithm has a vulnerability which can be leaked in side channel analysis. Thus we also have to consider side channel countermeasure. In this paper, we will propose the scenario of side channel analysis and confirm the vulnerability for HIGHT algorithm which is composed of ARX structure. Additionally, we will suggest countermeasure for HIGHT against side channel analysis. Finally, we will explain how much the effectiveness can be provided through comparison between countermeasure for AES and HIGHT.

NHS Reforms and Healthcare Market in the United Kingdom (영국의 NHS 개혁 및 의료시장 동향에 관한 연구)

  • Nam, Eun-Woo;Chun, Ki-Young
    • Korea Journal of Hospital Management
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    • v.8 no.4
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    • pp.1-25
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    • 2003
  • The wave of globalisation initiated by marketisation has increasingly penetrated into all sectors across the world, accordingly, the health & hospital service sector could not be made no escapes, and it currently faces the order of more marketised competition more than ever. Traditionally, the characteristic of the hospital services in the UK has considered as a model of social provision by government. However, contrary to our knowledge, the sphere of the hospital service in the UK has already been immersed in by the marketisation, in which the private actors have been embedded in order to tweak the activities of the hospital service with in the European Union. As the methodology of this research, the qualitative analysis, namely the interview with some doctors in Surgery, NHS Trusts staffs and relevant specialists in has been performed on April to May, 2003. And on the other hand, the various documents related to its service have been analysed. Thus, this paper will review the characteristics of the health service sector in the UK. In doing so, it will illuminate what would be the structural factors derived from its existing system, as a result, it will shed light on how the UK government makes an effort to resolve the problematic situation by reviewing the policy direction of Foundation Hospital proposed recently. In the next stage, it will analyse how all elements consist of the hospital management in the UK has been adjusted and be likely to be changed within Europe. More specifically focuses on how the private hospital service has been managed and related with the activities of its public hospital service-NHS Trusts. Also, under the circumstance, what private health insurance companies function will be studied. In conclusion, it will be concluded that what will be the implication of Korean hospital service market so as to correspond to globally open market by WTO. Now the UK health service system has faced a turning point of becoming more health care market internally and externally pressed by global and regional factors. Thus it is meaningful to scrutinize how a key part of social provision in the health care market system tends to adjust to globally marketised regulation.

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A Study on the Characteristic of Ubiquitous Infrastructure for u-City (u-City 도시기반시절의 특성에 관한 연구)

  • Eum, Min-Kyung;Song, Seung-Min;Kim, Do-Nyun
    • Korean Journal of Construction Engineering and Management
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    • v.12 no.5
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    • pp.93-102
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    • 2011
  • IT technologies applied in the urban places are being promoted in each area. Especially infrastructure is performed in the central role of technical support in urban area. However, u-City infrastructure has lack of integrated way and concentrated on only feasible technology which cause frequent substitution and the nested technology in urban area. Therefore this study sheds light on infrastructure through a overall considerations of urban compositional elements and interactions, and apply technology in the process of the industrial era, the domestic supply of urban infrastructure and the cycle comparison-analysis deal with the domestic implications when applied. The results of the study, first, the u-City infrastructure should be supplied by public. Second, u-City infrastructure is in need of the agile character, and standardization of the subtleties is needed. Third, a new system of integrated-macroscopic perspective should be established by changes that influenced by convergences of IT technologies and infrastructures. Fourth, u-City infrastructures planning should consider interactions of services, devices and systems.

The Effect of $PtCl_4$ Concentration on Dye-Sensitized Solar Cell Efficiency ($PtCl_4$ 농도에 따른 염료감응형 태양전지의 효율 변화)

  • Seo, Hyun-Seung;Park, Mi-Ju;Choi, Eun-Chang;Lee, Sung-Uk;Kim, Hyung-Jin;Hong, Byung-You
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.435-436
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    • 2008
  • Dye-sensitized Solar Cells(DSSCs) which convert incident sun light into electricity were expected to overcome global warming and depletion of fossil fuels. And it is one of study that is lately getting into the spotlight because manufacturing method is more simple and inexpensive than existing silicon solar cells. In this respect, DSSCs are in the limelight as the next generation solar cells. DSSCs are generally composed of a dye-modified $TiO_2$ photoelectrode, a Pt counter electrode, and an electrolytes containing a redox couple$(I^-/I_3^-)$. Among these elements, pt electrode were prepared by applying electric potential to FTO substrate in the $H_2PtCl_6$ solution. In this study, we report the solar cell efficiency depending on $PtCl_4$ concentration change. $PtCl_4$ concentration was 1mM, 5mM, 10mM, and 20mM, and adhered on FTO glass substrate by sintering process. When applied each $PtCl_4$ counter electrode on DSSC, the best efficiency was found at 10mM of $PtCl_4$ concentration. The catalyst promotes the movement of electron from the counter electrode to the electrolyte the higher the molarity, the better the efficiency. However, in case of 20mM, it is estimated that over-deposited $PtCl_4$ tends to restrict the movement of electron due to its bundle formation.

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THE ELECTROCHEMICAL STUDY ON CORROSION RESISTANCE OF VARIOUS DENIAL MAGNETIC ATTACHMENTS (수종 치과용 자석유지장치의 부식저항성에 대한 전기화학적 연구)

  • Sohn Byoung-Sup;Chang Ik-Tae;Heo Seong-Joo;Keak Jai-Young
    • The Journal of Korean Academy of Prosthodontics
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    • v.39 no.4
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    • pp.336-350
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    • 2001
  • The purpose of this study was to investigate corrosion tendency and to compare corrosion resistance of three dental magnetic attachments and its keeper alloy by coercive, electrochemical method. By using petentiodynamic polarization technique, magnetic elements and its keeper alloy of Magfit EX600 system(MF, MFK), Dyna ES regular system(DN, DNK) and Shiner SR magnet system(SR, SRK) were corroded electrochemically in 0.9% NaCl electrolytic solution. Open-circuit potential and anodic polarization curve was measured with Potentiostat(model 273 EG&E) and polarization curve was created by current density per square area following scanning of increased series of voltage in the rate of 1.0mV per second. Before and after electrochemical corrosion, the surface roughness test was done. Thereafter the change of mean surface roughness value(Ra) and mean peak value(Rt) of surface roughness was compared one another. In order to observe the corroded surface of each specimen, metallurgical light microscopic(${\times}37.5$) and scanning electron microscopic view(SEM ${\times}100$) was taken and compared one another. Conclusion is followings. 1. All of six covering metal of dental magnetic attachments and its keeper alloy were corroded in various degree after electrochemical corrosion. 2. The corrosion resistance of which used in this experiment is the following in high order; DNK, MFK, DN, MF, SRK and SR. 3. Especially Shiner magnet system and its keeper alloy were more severely corroded after electrochemical corrosion and the change of Ra Rt value were more increased than others. 4 Metallurgical and scanning electron microscopic view showed the pitting corrosion tendency of all experimental alloy but DNK and SR. 5. Covering metal of magnet was more corroded than its keeper alloy.

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Design of an Ultra-Wideband LPDA Antenna for the Feeder of an Airborne Spinning Direction-Finding Reflector Antenna (공중 회전 방향탐지 반사판 안테나 급전기용 초광대역 LPDA 안테나 설계)

  • Park, Young-Ju;Park, Dong-Chul
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.7
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    • pp.653-659
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    • 2016
  • This paper proposes an ultra-wideband Log-Periodic Dipole Array(LPDA) antenna for the feeder of a reflector antenna to be used for airborne spinning direction-finding and detecting wideband signals. To obtain the ultra-wideband characteristics over the 20:1 bandwidth from S to Ka band, the radiation elements of the antenna were printed on a substrate and a wedge-typed dielectric supporter with robust structure was inserted between the substrates. Also, the center portion of the supporter was replaced by a styrofoam material to reduce the supporter weight. The 5-dB return loss of the designed LPDA antenna showed ultra-wideband characteristics, which are 37.57:1(1.09~40.95 GHz) in the simulation and 33.85:1(1.31~44.35 GHz) in the measurement. We achieved the required gains of 5.78 dBi in the simulation and 5.76 dBi in the measurement in the operating band. The proposed robust, light-weight, and ultra-wideband LPDA antenna confirmed that it can be applied for airborne applications.

Art and Fashion Design Based on Charles Baudelaire's Aesthetic Perspective (보들레르의 미적 관점에 의한 예술과 패션디자인)

  • Kim, Yon-Son;Geum, Key-Sook
    • Journal of the Korean Society of Costume
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    • v.58 no.1
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    • pp.17-32
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    • 2008
  • This study focuses on the analysis of Baudelaire's aesthetic perspective which has established a theoretical basis on research of the critical reviews' salon exhibitions as written by Baudelaire. Charles Pierre Baudelaire(1821-1867) having lived during the latter part of Neo-classicism and the era of Romanticism and Impressionism, Baudelaire displayed opposition to customary realities such as social ideology or religious authority that suppressed human nature. Also he pioneered a new genre known as art criticism and wrote much that provided important insights on the essential elements of artistic work, modernity and trend, as well as art definition and art categories. The aesthetic perspective and creative spirit were formed by Baudelaire, during his age were also reconfirmed in the successive ages of modernism and postmodernism. As such, this study sheds light on how Baudelaire's aesthetic perspective was not only temporarily assertion but it is consistently applied to modern art and fashion area. What is more important that, Baudelaire admired new artificial beauty that is created by the human soul liberated from natural instincts or desires. Especially, informed by strangeness and distinctiveness, Baudelaire's view of fashion ran along the same vein as his view of art, and these views form the basis of that creative spirit which situated western fashion on a center of the world. In conclusion, the research on Baudelaire's aesthetic perspective will reaffirm a firm awareness of the creative spirit essential to globally-oriented creative artists and designers who work within the circumstance of the 21st century, a time when the paving of new aesthetic paths is necessary. The research also offers a clear understanding of the aesthetic values demanded by this age.