• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.259-264
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• 2004

The critical component of combustor having high combustion efficiency for high performance liquid rocket engine is injector. The results of design and hot firing tests of six sub-scale combustors which have respectively an impinging type injector(1ea.), an bi-propellant swirl closed injector(1ea.), and hi-propellant swirl mixed injector(4ea.) were described in this paper. The combustion test were successfully performed. The combustion efficiency have higher value than predicted value and high frequency combustion instability does not occur.

• Journal of Digital Convergence
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• v.16 no.4
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• pp.39-47
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• 2018

This paper aim to propose and suggest for government to reinvent and re-steering the policy on the 4th industrial revolution in Korea. To do it, this paper annalize the advanced country's policies and hard-data sets from many international research institutes. So this paper emphasized the concept and frame of socio-technical system approach by Geels. According to this approach, this paper can get a conclusion that Korea government has to focus on the roles to solve the big social dilemma with high-tech tools from the 4th industrial revolution. And this paper point out the necessary of increasing the diversity and multidisciplinary in 4th industrial revolution policy of Korean government. These findings of this paper recommend for Korea to redesigns the governance mechanism and legislation platform and to design the future readiness.

• The Korean Journal of Quaternary Research
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• v.16 no.2
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• pp.1-8
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• 2002

In this paper, the writer attempts to clarify causes by general man and weather factor on forest fire occurrence in Kosong-Area, 1995-2001. The major results are summarized as follows: The forest fire at Kojin-ri, Sonyusil-ri and Majwa-ri occurred at the same area over 3 times and that Hakya-ri, Songdae-ri and Inhung-ri, at the adjoining land over 3times. In the total 46 times of forest fire, fire frequence was greatest in March(11 time) and April(11 time) followed by November(7 time), January(6 time), February(6 time). December(3 time), October(2 time). Hours on frequent forest fire are from 11:00 till 18:00. Number for forest fire occurrence by causes was greatest in military training followed by burning paddy fields, debris burning, burning agricultural debris, visiting a grave, cigarette and arson. Frequent forest fire in Kosong-Area coincide not only with above normal temperatures, but also with below normal relative humidity. When the strong winds appear at Kosong-Area, the properties of daily surface chart re the south high and north low pressure pattern in the Far East Asia.

• Congress of the korean instutite of fire investigation
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• 2010.12a
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• pp.147-171
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• 2010

도장작업은 기계 기구, 금속, 자동차, 전기 전자, 선박, 가구제조업 등 각종 사업장에서 많이 취급되고 있는 작업으로서 취급물질이 대부분 합성수지 유기용매 등 인화성 또는 가연성 액체이거나 가연성 분체로서 용매 또는 분진으로 인한 폭발 화재의 위험성이 아주 높은 실정이다. 보통 4류 위험물의 유증기는 공기보다 무겁다 라는 생각으로 발생된 모든 유증기는 위험물 인근에 체류할 것이라는 생각을 하지만 상온에서 증발한 유증기 대부분은 인근의 대기와의 밀도차에 의해 주변으로 흩어지거나 연소하고 중량(重量)의 유증기만이 남아 화재조사에서 중요한 단서로 역할을 한다. 대부분분의 페인트 제품이 가열과 동시에 끊기 시작해서 비등점 측정이 어려웠고 발화점이 비슷한 다른 페인트에 비해 중량(重量)유증기 발생이 단시간 동안 낮은 온도에서 많이 발생한 것은 페인트의 안료가 유증기 발생을 방해해서 시너의 유증기 발생량과 동일한 양의 페인트 유증기 발생시간이 더 걸린 것 같다. 대부분의 유증기는 집진시설을 통해 A/C타워의 활성탄에 흡착되어 제거된다. 하지만 슬러지에 남아있는 희석제는 A/C타워를 정지하고 집진시설등의 배관에 있는 슬러지 청소 과정에서 주위 열원에 의해 많은 유증기를 발생하여 화재의 위험성이 존재함으로 작업자의 각별한 주의가 필요하다.

• Animal Systematics, Evolution and Diversity
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• v.15 no.1
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• pp.51-65
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• 1999

Gaillardiellus orientalis (Odhner, 1925) has been reared in the laboratory, form hatching to the first young crab stage at $25^{\circ}C$. The four zoeal stages and one megalopal stage are described and illustrated in detail. Within the subfamily Actaeinae, the zoea of G. orientalis differs from the other known zoeae in the characteristics of the antenna and the telson.

• Journal of Advanced Marine Engineering and Technology
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• v.26 no.6
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• pp.705-711
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• 2002

디젤기관은 실린더 내경의 크기, 실린더 수 및 회전수에 따라 착화지연, 연소지연 및 디젤기관의 각종 정수가 달라지므로 비선형이 심한 시스템이다. 본 연구에서는 신경회로망을 이용하여 발전기를 구동하는 디젤 기관의 속도를 제어하는 디젤기관 신경회로망 디지털조속기를 제안한다. 이를 위하여 3상 50㎾ 발전기를 구동하는 4행정 4실린더, 1800 rpm ISUTSU 디젤기관의 실제 운전데이터로부터 뉴럴에뮬레이터를 구한다. 최적치 뉴럴에뮬레이터 구성을 위하여 다양한 역전파알고리즘으로 학습을 행하고 결과를 비교한다. 또한 디젤기관의 역으로부터 뉴럴 제어기를 구성하고 뉴럴에뮬레이터로 시뮬레이션을 행한다. 외란이 존재하는 경우에도 효과적인 뉴럴제어기를 구성하기 위하여 선택적 뉴럴제어 기의 사용을 제안한다. 또한 응답성을 향상하고 정확한 목표치추종을 위하여 PI제어기를 보조제어기로 사용하는 하이브리드제어기를 구성하여 시뮬레이션을 통하여 성능이 향상됨을 보인다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.4
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• pp.300-309
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• 2017

A spacecraft obtains a reaction momentum required for an orbit correction and an attitude control by exhausting a combustion gas through a small thruster in space. If the exhaust plume collides with spacecraft surfaces, it is very important to predict the exhaust plume behavior of the thruster when designing a satellite, because a generated disturbance force/torque, a heat load and a surface contamination can yield a life shortening and a reduction of the spacecraft function. The purpose of the present study is to ensure the core technology required for the spacecraft design by analyzing numerically the exhaust gas behavior of the 10 N class bipropellant thruster for an attitude control of the spacecraft. To do this, calculation results of chemical equilibrium reaction between a MMH for fuel and a NTO for oxidizer, and continuum region of the nozzle inside are implemented as inlet conditions of the DSMC method for the exhaust plume analysis. From these results, it is possible to predict a nonequilibrium expansion such as a species separation and a backflow in the vicinity of the bipropellant thruster nozzle.

• The Science & Technology
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• v.32 no.2 s.357
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• pp.86-87
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• 1999

98년 10월 27일부터 3일간 미국 세인트루이스에서 제13차 미국정밀학회 연례학술회의가 열렸다. 유럽ㆍ한국ㆍ일본 등 각국에서 3백여명이 참석한 이번 학술대회에서 강원대 장인배교수 연구팀은 자기부상을 이용한 초정밀 직선운동 테이블에 대한 연구를 4년째 발표하여 많은 찬사를 받았다. 이번 학회는 렌즈가공을 주 대상으로 한 연삭 및 폴리싱 등의 가공방법에 대한 연구가 주종을 이루었다.

• The Korean Journal of Quaternary Research
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• v.23 no.2
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• pp.13-33
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• 2009

Mineralogical analysis with petrographic microscope and XRD was carried out to verify manufacturing technique of the tiles(9 samples) and kiln wall materials(5 samples) from the Anchang-ri history site in Wonju county. One of the results we found is such that during the tile manufacturing process fine tile fragments or wall materials might be added instead of chamottes to maintain tile pattern. Abandoned tiles or wall materials were recycled repeatedly, which may be supported by the recycled chamottes that made from iron-rich fine aggregates or disposed kiln wall materials in many samples analyzed. The tiles and wall materials are divided into 3 types, including low temperature type (below $800^{\circ}C$), intermediate temperature type ($800-930^{\circ}C$) and high temperature type ($930-1470^{\circ}C$) as a function of firing temperature which deduced by mineral assemblages identified under petrographic microscope and by XRD composition. Both Kiln A8 of Choseon Dynasty and wall material AW5 were burned at the highest temperature among the all analyzed samples.

• The Journal of the Petrological Society of Korea
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• v.23 no.2
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• pp.75-103
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• 2014

The Quaternary faults are extensively observed along major inherited fault zones (i.e. Yangsan Fault System, Ulsan Fault, Yeonil Tectonic Line, Ocheon Fault System) in SE Korea. Their geometry and kinematics provide a very useful piece of information about the Quaternary crustal deformation and stress field in and around Korean Peninsula. Using magnetic fabrics (AMS), we attempted to determine the slip senses of Jinti, Mohwa, Suseongji2, and Wangsan faults and then interpreted the fabric development process of fault gouge and the characteristics of stress field during the Quaternary. All the magnetic fabrics of the faults, except the Wangsan Fault, consistently indicate a dominant reverse-slip sense with weak strike-slip component. Most of the oblate fabrics are nearly parallel to the fault surface and the anisotropy degrees generally increase in proportion to the oblatenesses. These results suggest that the fabrics of the fault gouges resulted from a progressive deformation due to continuous simple shear during the last reactivation stage as reverse faulting. It is also interpreted that the pre-existing fabrics were overwhelmed and obliterated by the re-activated faulting. Paleostress field calculated from the fault slip data indicates an ENE-WNW compressive stress, which is in accord with those determined from previous fault tectonic analysis, focal mechanism solution, and hydraulic fracturing test in and around Korean Peninsula.