• Title/Summary/Keyword: Long Gap

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First-principles Calculations of the Phonon Transport in Carbon Atomic Chains Based on Atomistic Green's Function Formalism

  • Kim, Hu Sung;Park, Min Kyu;Kim, Yong-Hoon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.425.1-425.1
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    • 2014
  • Thermal transport in nanomaterials is not only scientifically interesting but also technological important for various future electronic, bio, and energy device applications. Among the various computation approaches to investigate lattice thermal transport phenomena in nanoscale, the atomistic nonequilibrium Green's function approach based on first-principles density functional theory calculations appeared as a promising method given the continued miniaturization of devices and the difficulty of developing classical force constants for novel nanoscale interfaces. Among the nanometerials, carbon atomic chains, namely the cumulene (all-doulble bonds, ${\cdots}C=C=C=C{\cdots}$) and polyyne (alternation of single and triple bonds, ${\cdots}C{\equiv}C-C{\equiv}C{\cdots}$) can be considered as the extream cases of interconnction materials for nanodevices. After the discovery and realization of carbon atomic chains, their electronic transport properties have been widely studied. For the thermal transport properties, however, there have been few literatures for this simple linear chain system. In this work, we first report on the development of a non-equilibrium Green's function theory-based computational tool for atomistic thermal transport calculations of nanojunctions. Using the developed tool, we investigated phonon dispersion and transmission properties of polyethylene (${\cdots}CH2-CH2-CH2-CH2{\cdots}$) and polyene (${\cdots}CH-CH-CH-CH{\cdots}$) structures as well as the cumulene and polyyne. The resulting phonon dispersion from polyethylene and polyene showed agreement with previous results. Compared to the cumulene, the gap was found near the ${\Gamma}$ point of the phonon dispersion of polyyne as the prediction of Peierls distortion, and this feature was reflected in the phonon transmission of polyyne. We also investigated the range of interatomic force interactions with increase in the size of the simulation system to check the convergence criteria. Compared to polyethylene and polyene, polyyne and cumulene showed spatially long-ranged force interactions. This is reflected on the differences in phonon transport caused by the delicate differences in electronic structure.

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BPMN2XPDL: Transformation from BPMN to XPDL for a business process (BPMN2XPDL : 비즈니스 프로세스에 대한 BPMN 표기법을 XPDL 언어로의 변환)

  • Park Jung-Up;Jung Moon-Young;Jo Myung-Hyun;Kim Hak-Soo;Son Jin-Hyun
    • The KIPS Transactions:PartD
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    • v.13D no.4 s.107
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    • pp.535-548
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    • 2006
  • To formally describe business process, many business process languages have been so far specified with different origins and goals such as XPDL, BPML and BPELAWS. Especially, XPDL proposed by WfMC has been widely used in various business process environments for a long time. On the other hand, the necessity of a standard graphical notation for a business process may create BPMN driven by BPMI. Because BPMN is composed of graphical constructs which can be used to graphically depict business process, BPMN-formed business processes should ultimately be converted to their corresponding semantically equivalent business process language(XPDL). Then, the business process languages can be consequently executed by business process engines. In this paper, we proposed a transformation mechanism from BPMN to XPDL for a business process. By this paper, We minimized the difference between process designers and process execution modules as reducing the gap of semantics between BPMN and XPDL.

A Study of Development of All Wheel Steering ECU in Bi-modal Tram (저상굴절버스의 전 차륜 조향 시스템 ECU 개발에 대한 연구)

  • Kim, Ki-Jeong;Lee, Soo-Ho;Chung, Ki-Hyun;Choi, Kyung-Hee;Park, Tae-Won;Moon, Kyeong-Ho
    • The KIPS Transactions:PartA
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    • v.17A no.1
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    • pp.19-26
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    • 2010
  • As standard of living is higher and aging society is coming, it is needed to develop transportation that is easy to use for weak person. To comply with the demands, it is started to make Bi-modal Tram that is on KRRI(Korea Railroad Research Institute)'s hands. This tram has to have good accessibility like bus, be low level from ground like subway, and park accurately so wheel chair's or passenger's foot can't fall into the gap. But Bi-modal Tram have long length, so it need development of All Wheel Steering System. The Bi-modal Tram that have all wheel steering system steer not only the first axle but also the second and third axle from the first axle or articulation angle, and velocity, and so on. At this study, we discuss AWS ECU's development process.

A Sunglasses Design to Prevent Snow Blindness at High Altitude (설맹 방지를 위한 고소등반용 선글라스 디자인)

  • Choi, Byung-Jin;Jang, Joon-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.4
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    • pp.19-22
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    • 2007
  • Recently, the population of people exploring High Mountain trekking or expedition is increasing as an increase in the backpackers. Many accidents occurring at High Mountain above 6,000 m are the results of snow blindness. The damage of cornea and/or retina is direct cause of snow blindness. The UV intensity increases on the hand, along with the altitude caused by decrease in the atmospheric pressure, on the other hand the reflections by bright snow at high mountain area. And it increases approximately 3 times and 4 times higher than the ground level at altitude of 4,000 m and 8,000 m, respectively. The use of sunglasses is more favorable than goggles for the protection of snow blindness at High Mountains. The eye frames that have high mechanical strength and the plastic lenses which can protect UV 100% are recommended. The attachable shielding pads are needed to prevent the incident UV light reflected or scattered from the gap between glasses frame and face. The sunglasses must have flexible and long temples to wind the ears adequately for the prevention of detachment during climbing and it is recommended that the metal frame to be coated with plastics to prevent the eye surroundings from frostbite.

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Consideration of Making Techniques and Deterioration Assessment using Radiography for the Iron Buddha Statues (방사선 투과촬영을 활용한 철불의 손상도 평가 및 제작기법 고찰)

  • Han, Na Ra;Lee, Chan Hee;Yi, Jeong Eun
    • Journal of Conservation Science
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    • v.30 no.1
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    • pp.81-93
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    • 2014
  • As the Seated Iron Buddha Statues, Vairocana Buddha of Dopiansa Temple in Cheolwon, Nosana Buddha of Samhwasa Temple in Donghae and Sakyamuni of Mangisa Temple in Pyeongtaek were made during Unified Silla to Koryo Dynasty. These are damaged degradation which are crack, break-out, peel off and various pollutant. As a result of deterioration evaluation using radiography, crack, gap, break-out, pore space and restoration material are confirmed inside in the Buddha Statues. Based on iron strength, the Buddha Statues will be maintain current state as long as a high external impact is not applied. Also, iron core and nails used for fixing of internal and external framework were observed in the Buddha Statues. According to prominent line of surface, embossed inscription, hands cast separately and combined, the Buddha Statues were made by using division casting.

Detection of genetic abnormalities in human sperm, oocytes, and preimplantation embryos using fluorescence in situ hybridization (FISH) (Fluorescence in situ hybridization(FISH) 기법을 이용한 인간 생식세포 및 착상전 배아의 유전이상 검색)

  • 방명걸
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 1998.07a
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    • pp.12-18
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    • 1998
  • Tremendous progress has been made over the past quarter-century studying the genetics of gametogenesis and the resulting gametes and embryos. Studies merging molecular techniques and conventional cytogenetics are now beginning to bridge the gap between what we have learned about the meiotic process in males and females and what we know of the mitotic chromosomes of zygotes. Numerical abnormalities in sperm, oocytes and embryo can now diagnosed by fluorescence in situ hybridization (FISH). "At risk" couples can, therefore, have only unaffected embryos replaced in the sterus and avoid the possibility of terminating a pregnancy that might only be diagnosed as affected later gestation. Single-cell genetic analysis has also provided powerful tools for studying genetic defects arising during early human development. Recent studies of sperms, oocytes and cleavage-stage human embryos have revealed an unexpectedly high incidence. These genetic abnormalities are likely to contribute to early pregnancy loss and have important implications for improving pregnancy rates in infertile couples by assisted reproduction. The widespread use of preimplantation genetic diagnosis (PGD) awaits further documentatio of safety and accuracy. Other issues also must be addressed. First, the ethical issues regarding germ cell and embryo screening must be addressed including what diseases are serious enough to warrant the procedure. Another concern is the use of this technology for non-genetic disorders such as gender selection. Finally, the experimental nature of these procedure must continually be discussed with patients, and long-term follow-up studies must be undertaken. Development of more accurate and less expensive assays coupled with improved assisted reproductive technology success rates may make PGD a more widely use clinical tool. The future awaits these development.velopment.

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Fabrication and Fault Test Results of Bi-2212/Cu-Ni Tubes for Superconducting Fault Current Limiting Elements (Bi-2212/Cu-Ni 튜브로 제작한 초전도 한류소자의 단락사고시험 결과)

  • Oh, S.Y.;Yim, S.W.;Yu, S.D.;Kim, H.R.;Hyun, O.B.
    • Progress in Superconductivity
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    • v.10 no.1
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    • pp.45-49
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    • 2008
  • For the development of superconducting fault current limiters (SFCLs), fault current limiting elements were fabricated out of Bi-2212 bulk tubes and tested. The SFCL elements consisted of tube shaped Bi-2212 bulks and metal shunts for the stabilizers. Firstly, the Bi-2212 bulk tubes were processed based on a design of monofilar coils in order to acquire large resistance and high voltage rating. 300 mm-long Bi-2212 tubes were designed to have the current path of 410 cm in length with 24 turns and 41 mm in diameter. The processed monofilar coil, as designed, had 300 A $I_c$ at 77 K. The fabricated superconducting monofilar coils were affixed to Cu-Ni alloy as that of stabilizers. The Cu-Ni alloys were processed to have the same shape of the superconducting monofilar coils. The Cu-Ni coil had resistivity of 32 ${\mu}{\Omega}$-cm at 77 K and 37 ${\mu}{\Omega}$-cm at 300 K. The metal shunts were attached to the outside of the Bi-2212 monofilar coil by a soldering technique. After the terminals made of copper were attached to both ends of the superconductor-metal shunt composite, the gap between the turns and the surface of the elements was filled with an epoxy and a dense mesh made of FRP in order to enhance the mechanical strength. The completed SFCL elements went through fault tests, and we confirmed that the voltage rating of 143 $V_{rms}$ (E =0.35 $V_{rms}$/cm) could be accomplished.

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Characteristics of Seasonal Wave, Wave-Induced Current and Sediment Transport in Haeundae Beach (해운대 해수욕장의 계절별 파랑, 해빈류 및 퇴적물이동 특성)

  • Lee, Jong-Sup;Tac, Dae-Ho;Woo, Jin-Gap
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.6
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    • pp.574-585
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    • 2007
  • To analyze the incident wave characteristics around Haeundae beach the long-term deep water wave data computed by wave hindcast method were used and a continuous wave observation was carried out for 1 year at the 20 m of water depth in front of Haeundae beach. Wave observation data showd that the prevalent wave direction was SSW-S in spring and summer seasons while E-SE in autumn and winter. A numerical modeling shows that the waves from E-SE are refracted strongly due to the shoal developed at the south-east side of Haeundae beach. The simulation also shows inflowing nearshore current along the east coast of the beach develops strongly in autumn and winter. Radioactive isotope tracer experiment for 155 days indicated that the tracers moves to the on-shore direction in the 1st and 2nd tracking then dispersed to the E-W direction along the shore.

Development of a Coverall Design for Infant Body Shapes (유유아 체형에 적합한 커버롤 디자인 개발)

  • Lee, Yoon-Kyung;Kim, Min-Ja;Nam, Yun-Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.2
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    • pp.189-199
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    • 2010
  • This study develops a coverall design for the body shape and movement of infants. This research analyzed these processes: 1. The current coverall styles preferred for infants. 2. The appropriate products for the real size, body shape, movement, and fit of infants. 3. The observations of the 6 months to 9 months movement and development of infants. 4. The design and creation of a new coverall base in this study, and to check the suitable test the developed coverall design for the infant. The result of this study are: A coverall for infants that lie or crawl on the floor must avoid opening in the center front and a gore has to be added at the crotch of the pants for the better movement of infants. These ways provide infants a neat appearance and easy movement. The test of developed designs shows that the developed coverall design covers the size gap of the trunk loop according to the growth of the infant and the movement of the legs; in addition it provides a positive aesthetic effect. The waistline in the developed coverall (a waistline that should exist lower than the body waistline of the infant) can reduce seam stress because the pressure of the seam line can be absorbed in a dipper. It is one of the suitable design points for infants lying prone all day long in this study.

Comparison of the Health Insurance Systems of South Korea and Peru

  • Kim, Yanghee;Tantalean-Del-Aguila, Martin;Dronina, Yuliya;Nam, Eun Woo
    • Health Policy and Management
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    • v.30 no.2
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    • pp.253-262
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    • 2020
  • Background: The public health care system of a country is shaped and driven by its historical background as well as social, economic, and cultural structures. This study sheds light on the unique features, strengths, and weaknesses of the health insurance systems of South Korea (Korea) and Peru. Methods: The capacity mapping tool was used to explore the Korean and Peruvian population and geographical structures; health insurance laws, regulations, and policies; payment systems; eligibility and contribution collection; and long-term care insurance. Results: The study found that the Korean government took the lead in integrating multiple insurers into a single-payer system in an effort to reinforce and stabilize its health insurance system in 2000. Peru has been developed mixed model such based on taxes and contributions, to address a gap between different social classes. Peruvian government developed a two-axis system, one for low-income earners, financed by taxes, and another financed by contributions paid by workers and government officials in the formal sector. Peru has introduced many variations to its fee payment and insurer systems, target population, and coverage scope, and maintains its health insurance system accordingly to this day. Conclusion: The current study provides observation of the Health Insurance System in two different countries and helps to understand possible ways to improve the health insurance system in both countries. Based on this study, Peru will be able to see how its system differs from Korea's and benefit from the related policy implications.