• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.1
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• pp.72-79
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• 2018

An experimental study was performed to investigate the chemiluminescence characteristics in the spray combustion of ultransonically atomized kerosene. The radical intensity of the spray flame was measured using an ICCD camera and the amount of fuel consumed was obtained by a precise flow-rate measurement technique during combustion. Fuel consumption increased linearly with the increase in carrier-gas flow rate, and typical group combustion, which is a characteristic of spray combustion, was observed. It was found from the analysis of chemiluminescence that the maximum emission intensities of OH and CH radicals decrease, and they move downstream resulting in the increase in a vivid reaction zone as the spray flow rate increases.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.2
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• pp.53-59
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• 2019

LIBS plug, a simplified laser-induced breakdown spectroscopy(LIBS) device with the purpose of measuring the fuel distribution inside the combustion chamber, was developed and manufactured. The LIBS plug receives only two wavelengths (H:656.3 nm, O: 777 nm) that are closely related to the equivalence ratio in the overall spectrum. The calibration curve between the signal of the LIBS plug and the equivalence ratio was constructed, and the fuel distribution of gasoline-air and LPG-air mixtures was measured using the LIBS plug.

• Economic and Environmental Geology
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• v.34 no.1
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• pp.25-38
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• 2001

Contrasts in the style of the gold-silver mineralization in geologic and tectonic settings in Korea, together with radiometric age data, reflect the genetically different nature of hydrothermal activities, coinciding with the emplacement age and depth of Mesozoic magmatic activities. It represents a clear distinction between the plutonic settings of the Jurassic Daebo orogeny and the subvolcanic environments of the Cretaceous Bulgugsa igneous activities. During the Daebo igneous activities (about 200-130 Ma) coincident with orogenic time, gold mineralization took place between 197 and 127 Ma. The Jurassic deposits commonly show several characteristics: prominent association with pegmatites, low Ag/Au ratios in the ore-concentrating parts, massive vein morphology and a distinctively simple mineralogy including Fe-rich sphalerite, galena, chalcopyrite, Au-rich eIectrum. pyrrhotite and/or pyrite. During the Bulgugsa igneous activities (120-60 Ma), the precious-metal deposits are generally characterized by such features as complex vein morphology, medium to high AgiAu ratios in the ore concentrates, and abundance of ore minerals including base-metal sulfides, Ag sulfides, native silver, Ag sulfosalts and Ag tellurides. Vein morphology, mineralogical, fluid inclusion and stable isotope results indicate the diverse genetic natures of hydrothermal systems. The Jurassic Au-dominant deposits were formed at the relatively high temperature (about 300 to 450$^{\circ}$C) and deep-crustal level (>3.0 kb) from the hydrothermal fluids containing more amounts of magmatic waters (3180; 5-10 %0). It can be explained by the dominant ore-depositing mechanisms as CO2 boiling and sulfidation, suggestive of hypo/mesothermal environments. In contrast, mineralization of the Cretaceous Au-Ag type (108-71 Ma) and Agdominant type (98-71 Ma) occurred at relatively low temperature (about 200 to 350$^{\circ}$C) and shallow-crustal level «1.0 kb) from the ore-fonning fluids containing more amounts of less-evolved meteoric waters (15180; -10-5%0). These characteristics of the Cretaceous precious-metal deposits can be attributed to the complexities in the ore-precipitating mechanisms (mixing, boiling, cooling), suggestive of epilmesothermal environments. Therefore, the differences of the emplacement depth between the Daebo and the Bulgugsa igneous activities directly influence the unique temporal and spatial association of the deposit type.

• Journal of the Korea Society of Computer and Information
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• v.25 no.11
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• pp.277-286
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• 2020

In this paper, we propose a new educational approach to help learners form concepts by identifying the properties of programming concepts targeting a group of experts in programming education. Therefore, we confirmed the typical properties of concepts by programming education experts for programming learning elements through conceptual metaphor analysis, which is a qualitative research method, and confirmed the validity through the delphi method. As a result of this study, we identified 17 typical properties of programming concepts that learners should form in programming education. The conclusions of this study are that need to compose the educational content more specifically for the conceptualization of learners' programming as follows: 1)the concept of a variable is to understand how to store data, how to set a name, what an address has, how to change a value, various types of variables, and the meaning of the size of a variable, 2)the concept of operator is to understand how to operate the four rules, how to deal with it logically, how to connect according to priority, meaning of operation symbols, and how to compare, 3)the concept of the control structure is to understand how to control the execution flow, how to make a logical judgment, how to set an execution rule, meaning of sequential execution, and how to repeat executing.

• Archives of design research
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• no.16
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• pp.101-110
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• 1996

CHOOSA GORACK which is a typical example of traditional houses in the CHO SEON dynasty consists of the four terraced builfing group. Among those,SADANG CHAI are located in the highest level,and SADANG CHAI and SADANG CHAI are toward south direction.It means that building orientation and level were influenced by the distinction of social level and the idea of ancester worship. Floor and ceiling level in the same building is different which was caused by the distinetion of social level in the CHO SEON dynasty and an ariental dual as a variety of openings,exposed ceilings,and furniture against a wall were creating a typical Korean visual harmony. Although the furniture and equipments were very important elements in ONDOL BANG the occupance ratio of these were low because the free space in BANG should be utilized effectively to accommodate the space variation.Both an AN CHAI and SARANG CHAI were composed by the standard space module called KAN.And interior elements were established by several factors such as the human scale,the behavior pattern in traditional sitting life style, and the lumber size of post and lintel construction of Korean house.BANG and DAE GHUNG, composed of KAN,were expanded and arranged side by side so that the natural light and ventilation through them could be used in the result of the kind of lay out,traffic circulation was disturved.In conclusion,CHOOSA GOTACK was formed by the sirect effice of the KOREAN penisula. However this study was based on one sample. It may not enough to deduct soild conclusion.Therefore continuous and farher study is needed for the sestemane evaluation.

• Parasites, Hosts and Diseases
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• v.21 no.1
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• pp.87-94
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• 1983

Kala-azar는 우리나라에는 분포하지 않는 것으로 인정되고 있으나 과거 중국에서 감염되어 국내에서 관찰된 보고가 있는 질병이다. 최근에 중동 지방에서 감염되어 귀국하고 발병하였다고 생각되는 예를 보고한다. 서울에 주소를 둔 26세의 한국인 남자가 1년간 사우디 아라비아에서 건설기능공으로 근무하고 1981년 9월 귀국하여 약 8개월 후인 1982년 5월 경부터 심한 피로감, 전신쇠약, 복부의 수물등을 느끼기 시작하였다. 환자가 국립서울병원을 거쳐 서울대학교병원에 1982년 9월 17일 입원할 당시에는 간과 비장이 모두 14cm정도 만져질 만큼 부어있었고, 심한 체중 감소(4개월간 14kg의 감소), 적혈구, 백혈구, 혈소판등 모든 혈구의 감소등이 관찰되었다. 간생검을 통해 amastigote가 관찰되고 이는 투사전자현미경을 통해서 전형적인 amastigote형으로 확인되었다. 환자는 국외에서 구한 약제인 sodium antimony gluconate(Pentostam )와 각종 보조요법에 의해 치료를 받았다. 퇴원 직전에 시행한 간생검에서 괴사된 간 조직이 섬유화로 대치된 것이 확인되었고 충체는 관찰되지 않았다. 이 Kala-azar 에는 1952년 만주에 유입되어 보고된 3예 이후로는 처음 관찰된 것으로 중동에서 유입된 것으로는 첫번째 보고례이다. 최근 급격히 늘어난 해외 인력진출을 감안하면 해당 지역의 열대 풍토병에 대한 다각적인 대책이 절실히 요청된다.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.177-178
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• 2003

1934년 Formhals[1,2]에 의해 최초로 특허화된 전기방사(electrospinning)는 최근에 나노기술의 급격한 부각과 함께 과학분야에서 큰 관심의 대상이 되고 있다. 이러한 전기방사는 전형적인 섬유제조방법인 습식ㆍ건식ㆍ용융방사와는 달리 전기적인 힘(electric force)을 이용하여 머리카락 굵기의 100분의 1의 작은 크기의 직경을 갖는 섬유를 제조할 수 있는 방법이다[1,2]. 전기방사에 의해 제조된 웹은 단위 면적당 큰 표면적, 작은 기공, 높은 다공성을 가지고 있기 때문에 필터, 복합체의 강화제, 조직공학에서의 담체(scallold)뿐만 아니라 의료 분야 등에 응용될 수 있다[1,2]. (중략)

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.07a
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• pp.114-118
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• 2001

졸-겔법으로 Pt/Ti/$SiO_2$/Si 기판위에 $Bi_{3.7}$/$La_{0.75}$$Ti_3O_{12}$(BLT) 강유전체 박막을 형성하였다. As-coated BLT 박막은 $600^{\circ}C$의 후속 열처리온도에서 결정화 되었으며 전형적인 Bi 층상 페롭스카이트 결정구조를 나타내었다. 또한 후속 열처리온도를 증가함에 따라 결정성이 향상되었다. $700^{\circ}C$의 온도에서 후속 열처리된 BLT 박막의 비 유전상수($\varepsilon_{r}$)와 유전손실($\textrm{tan}\delta$)은 5KHz 주파수에서 약 402와 0.04를 각각 나타내었다 $800^{\circ}C$에서 후속 열처리된 BLT박막의 경우 5V의 인가 전압에서 잔류분극 2Pr($Pr^{+}$-$Pr^{-}$)값은 약 32.5$\mu$C/$Cm^2$을 나타내었다.

• 한국게임학회지
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• v.6 no.1
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• pp.44-47
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• 2009

분명한 것은 한국형 온라인게임의 특징적 원리들이 탑재되고 있는 방식과 현상은 점차 강화되고 있음에도 불구하고 게임사 주도적으로 전개되고 있는 산업의 성장모형은 평가기능으로 작동해야 할 조정 메커니즘의 원활한 흐름을 저해하는 길항관계에 있는 것은 사실이다. 이러한 문제를 인식하고 연구자는 게임연구의 활성화지점과 게임개발 테크놀로지가 가진 길항관계를 보완할 수 있는 디자인에 주목하고자 하였다. 게임디자인은 게임의 미적, 실용적, 경제적 가치를 창출하는 직무이면서 유관 콘텐츠산업과의 연계와 매개 가능성을 함의하고 있다는 측면에서 게임연구의 활성화지점의 매개로서 충분하다는 것이 연구자의 견해이다. 이 같은 주장의 전개를 위하여 국내에서 탄생한 온라인게임에 초점을 맞추고 국내 온라인게임의 전형이 되고 있는 핵 앤 슬래쉬(Hack & Slash) 방식과 허구적 공간에서의 게임화된 사회경험을 추구하는 스토리텔링 방식의 분석을 통해 국내형 온라인게임이 성취한 디자인 좌표를 검증하고, 이를 통해 국내 게임산업에 대두되고 있는 위기 스펙트럼과의 연관성은 어떤 것이며, 디자인은 어떠한 방향으로 매개되어야 할 것인지에 대한 의제로 접근하였다.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.11
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• pp.129-136
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• 2002

Electric vehicle body has to be subjected to uniform load and demand auxiliary equipment such as air pipe, electric wire pipe and gas pipe. Especially, lightweight vehicle body is salutary to save operating costs and fuel consumption. Cross beam supports the weight of passenger and electrical equipments and account for the most of weight of vehicle body. Therefore this study performs the size and the shape optimization of crossbeam for electric vehicle using GENESIS 7.0 and presents the effect of mass reduction and the shape of hole in cross beam.