• 한국자동차공학회논문집
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• 제12권1호
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• pp.122-129
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• 2004

Finite element analysis was performed to analyze structural safety of a new heavy-duty direct injection diesel engine. A half section of the in-line 6-cylinder engine was selected as a computational domain. A mapping method was used to project heat transfer coefficients from CFD results of engine coolant flow onto the FE model. The accurate setting of thermal boundary condition on the FE model was expected to result in improved prediction of temperature, cylinder bore distortion, and stresses. Characteristics of high cycle fatigue were investigated by assuming the engine was operated under the following five loading conditions repeatedly; assembly force, assembly force with thermal loading, alternating maximum gas pressure loading at each cylinder combined with assembly force and thermal loading. Distribution of fatigue safety factor was calculated by using it Haigh diagram in which the maximum and the minimum stresses were selected from the five loading cases.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1053-1055
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• 2005

At the moment, the operation methods for pad switch are different due to the differences of the manufacturer and the types or ratings of pad switches; accordingly, various types of the operation tools are required for the operation of pad switch. Sometimes, the operator uses conductive tool made of metal, or there is no sufficient space around the pad switch for operation and these kinds of problems are related with the potential safety accidents of the operators. Therefore, to solve these problems, new universal operation tool for pad switch, which only needs the change of operation head for various types of pad switches, has been developed. With this new tool, durability and safety of the operator can be achieve.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1496-1499
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• 2005

This paper was represented an electrostatics distribution analysis using FEM(finite element method) with industrial type Inkjet plotter. Here, we know electronic value with each system position by experiment. these were decreased by discharge through earth and electricity shielding. According to industrial development, all fields using chemical instrument and material are generated an electrostatics. Based on these, the big large position of electrostatics was obtained metal base of controller, nonconductor fiber between two rubber roller, head controller by moving roller etc., Therefore these were showed an electrostatics generation source and by rubbing and meager profits electric charge.

• Journal of Species Research
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• 제9권2호
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• pp.174-179
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• 2020

Larvae and pupae of Simulium (Eusimulium) satsumense were collected and recorded from Korea for the first time. Detailed descriptions and photographs of both immatures are provided. Currently, 42 species are known from the subgenus Eusimulium, which is found globally, mainly in the Holarctic Region, but unknown from Korea. Members of the subgenus Eusimulium are morphologically homogeneous in male, female, and pupa, making them extremely difficult to distinguish from one another. S. (E.) satsumense can be distinguished from other Korean black flies by the following combination of the characteristics: Pupa: Gill of four slender filaments, dorsalmost filament strongly divergent from other filaments; cocoon slipper shaped without anterodorsal projection; Larva: Head spots distinctly positive; postgenal cleft short, apically rounded or squared; antenna with proximal segment brown; abdominal segments IX with prominent ventral tubercles; and rectal papillae of three simple lobes. In addition to descriptions for larvae and pupae of the species, a key to genera and subgenera of Simulium of Korean black flies are also provided.

• 한국산업융합학회 논문집
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• 제5권4호
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• pp.313-320
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• 2002

A 2-dimensional $k-{\varepsilon}$ numerical model was developed to explore the effects of vehicle movement, jet fan and wind speed for the ventilation of road tunnels. To consider the temperature distribution in the tunnel, the energy equation was solved with a source term of the energy exhausted from vehicles. Although the tunnel ventilation can be made by the piston effect of vehicle movement, an additional ventilation is necessary when a head wind is existing. Jet fans may assist the air flow in the tunnel. However, more efficient ventilation system should be necessary, because the exhaust gas from vehicles flow along the road surface and it cannot be diffused in the longitudinal tunnel.

• 대한원격탐사학회지
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• 제10권1호
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• pp.43-53
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• 1994

삼림을 베어서 태우고 난 직 후의 라오스 북부 화전지역의 MOS-1 위성영상을 처리하여 유역분지 단위로 화전지역의 면적을 산출하였으며, 지형도상에서 얻어낸 하계망과의 상관관계를 분석하기 위하여 PC Arc - Info의 GIS software를 이용하였다. 그 결과 화전의 분포비율이 높은 유역분지에서는 1차수하천의 분기율도 높게 나타남을 알수 있으며, 라오스에 있어서 화전이 지표 의 침식과 토지의 황폐화를 초래하여 여러가지 환경문제를 유발시키는 원인이 된다는 것이 규명 되었다.

• Animal cells and systems
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• 제14권3호
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• pp.221-224
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• 2010

A new and rare perlid stonefly, Togoperla thinhi n. sp., is described from male and female adults and egg specimens from tropical central Vietnam. The male adult of T. thinhi n. sp. can be distinguished from other congeners by the distinct head markings, bilobed processes on the posterior margin of the abdominal tergum V, and S-shaped aedeagus. The female adult has a long and tongue-shaped subgenital plate on the abdominal sternum VIII, which extends to the posterior margin of the abdominal sternum IX. A male key to the Vietnamese species of Togoperla is provided. The finding of this new species provides evidence of an extension of the geographical distribution of Togoperla to tropical mainland Southeast Asia.

• 한국분무공학회지
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• 제24권1호
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• pp.1-7
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• 2019

This study was carried out to analyze the spray characteristics as a function of the operating parameters of urea injector used in Urea-SCR system of passenger diesel vehicle. Spray visualization and PDPA experiment were performed to analyze the macroscopic spray development and atomization performance of urea-water-solution. For the urea injector, the deformation of the spray head does not appear to be significant because it operates at a low pressure conditions, and the liquid core and primary droplet are observed throughout the operating conditions. No increase in atomization is seen when the operating pressure is increased, and the spray develops linearly due to poor atomization characteristics. The macroscopic spray behavior of the low-pressure urea injector is predictable through the modification of the Hiroyasu equation.

• 방사성폐기물학회지
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• 제19권4호
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• pp.533-546
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• 2021

Large earthquakes with (M_W > ~ 6) result in ground shaking, surface ruptures, and permanent deformation with displacement. The earthquakes would damage important facilities and infrastructure such as large industrial establishments, nuclear power plants, and waste disposal sites. In particular, earthquake ruptures associated with large earthquakes can affect geological and engineered barriers such as deep geological repositories that are used for storing hazardous radioactive wastes. Earthquake-driven faults and surface ruptures exhibit various fault zone structural characteristics such as direction of earthquake propagation and rupture and asymmetric displacement patterns. Therefore, estimating the respect distances and hazardous areas has been challenging. We propose that considering multiple parameters, such as fault types, distribution, scale, activity, linkage patterns, damage zones, and respect distances, enable accurate identification of the sites for deep geological repositories and important facilities. This information would enable earthquake hazard assessment and lower earthquake-resulted hazards in potential earthquake-prone areas.

• Nuclear Engineering and Technology
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• 제54권9호
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• pp.3415-3421
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• 2022

This paper is aimed to find out the impact of the geometrical parameters, mainly the radius and the height of a cylinder, on the SGEMP response including the famous scaling law in the classical cylinder model using a homemade PIC code UNIPIC-3D. We computed the electric fields at the center and at the edge on the emission head face with different radii and heights under normal X-rays incidence. The results show that the electric field will increase with the radius but decrease with the height. We analyze the scaling law that links the electric field product and fluence product, and whereafter an irreconcilable contradiction raises when the radius is changeable, which limits the application range of the scaling law. Moreover, the field-height-radius relation is found and described by a combination of logarithmic and minus one-quarter numerical fitting law firstly. Particle and magnetic field distributions are used to explain all the behaviors of the fields reasonably. All the findings will assist the evaluation of SGEMP response in spacecraft protection.