• The Korean Journal of Quaternary Research
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• v.22 no.1
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• pp.13-22
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• 2008

The Indian summer monsoon behaved in an abnormal way in 2002 and as a result there was a large deficiency in precipitation (especially in July) over a large part of the Indian subcontinent. For the study of deficient monsoon of 2002, a recent version of the NCAR regional climate model (RegCM3) has been used to examine the important features of summer monsoon circulations and precipitation during 2002. The main characteristics of wind fields at lower level (850 hPa) and upper level (200 hPa) and precipitation simulated with the RegCM3 over the Indian subcontinent are studied using different cumulus parameterization schemes namely, mass flux schemes, a simplified Kuo-type scheme and Emanuel (EMU) scheme. The monsoon circulation features simulated by RegCM3 are compared with the NCEP/NCAR reanalysis and simulated precipitation is validated against observation from the Global Precipitation Climatology Centre (GPCC). Validation of the wind fields at lower and upper levels shows that the use of Arakawa and Schubert (AS) closure in Grell convection scheme, a Kuo type and Emanuel schemes produces results close to the NCEP/NCAR reanalysis. Similarly, precipitation simulated with RegCM3 over different homogeneous zones of India with the AS closure in Grell is more close to the corresponding observed monthly and seasonal values. RegcM3 simulation also captured the spatial distribution of deficient rainfall in 2002.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.2
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• pp.195-202
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• 1998

In this study, we utilized various type of GPS observation measurements to get a camera projection center of the aerial triangulation and consequently to determine which type is acceptable. For the accuracy and the error analysis, comparison between a projection center from the conventional model adjustment and the result determined by the kinematic DGPS positioning which is fitted to the conventional model adjustment using 3D conformal transformation method has been made. The camera projection center is located within a $\pm{2m}$ for C/A code range measurements, $\pm{14cm}$ for L1 phase measurements and $\pm{10cm}$ for L1/L2 phase measurements with $1\sigma$. In this way, the accuracy of the camera projection center by the bundle block adjustment can be predicted.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.3
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• pp.237-242
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• 2012

Spaceborne pulse tube-type cryogenic compressors are widely used for space applications. To guarantee cooling performance of the compressor, mission life time and micor-vibration stability, suitable thermal control of compressor is required. Micro-vibration of the compressor is the one of the sources to degrade the pointing performance of observation satellite. In the present work, on-orbit thermal design of compressor in order not to degrade the performance of micro-vibration isolation system keeping the thermal control performance has been proposed and investigated through thermo-mechanical analysis.

• Journal of Korea Foundry Society
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• v.4 no.2
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• pp.96-101
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• 1984

The morphologies of eutectic cell formed during solidification affect on the mechanical properties in high Cr cast iron. In order to investigate the influence of Si on the structure, five kinds of specimen containing 16.42% Cr with varying amount of Si (0.51%, 1.17%, 2.22%, 2.71%, 3.56%) were poured into shell mould preheated $330^{\circ}C$ at $1510^{\circ}C$. The effect of Si on matrix in hypo-eutctic Cr cast iron (2.48% C, 16.42%) were studied through its mechanical tests and observation of microstructure using of metallurgical microscope, EPMA, SEM and Image analyzer systematically. The results obtained from the above studies are as follows: 1. Because of ${\Delta}T$ decreasing with increasing Si content, the morpologies of colony change into uniform bar-type carbide from plate-type ones, moreover eutectic colony size (Ew) becomes narrow and spacing of carbide wider. 2. As Si content increases, the amount of carbides also increases and most of Cr were dissolved in carbides while Si in matrix. 3. The hardness, tensile strength and wear resistance were increasing while impact value decreased with increasing Si content. 4. In fracture section, small amount of dimple pattern was observed in less than 1.17% Si but more than 2.22% Si river pattern was presented.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.427-430
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• 2008

The present study is a preliminary research improving the dwelling quality of apartment house as a kind of multi-family housing. The purpose of the study is to find out the present condition on noise level and types including residents' living noise in apartment units. The method was field survey consisted of field measurements on equivalent noise level, observation on noise type, and interview on residents' responses. The results are as follows. 1) Averages of indoor noise levels of subject houses were measured as $43.9{\sim}62.2\;dB(A)_{Leq5min}$, the average of each house except one was higher than the permissible level, 45 dB(A). 2) The noise types observed were mostly residents' living noise and classified as 'water hammer', 'living equipment noise', 'noise by family', 'hood noise', and 'kitchen noise' in own unit, 'walking and talking noise in stairs and corridors', 'noise by neighborhood house', 'noise by the upper story' in building, and outdoor noise. 3) The residents show slightly non-positive responses at 'noise by the upper story', 'noise by neighborhood house', 'water hammer', and 'noise by family'. Therefore, it is required to plan for preventing deterioration of the sound environment quality by residents' living noise in own unit as well as by neighborhood houses.

• Journal of The Korean Association For Science Education
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• v.14 no.1
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• pp.45-57
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• 1994

The purpose of this study is to verify whether the FAST program is the Inquiry Science Curricular Materials, through the Comparison and Analysis of Inquiry Activities between the FAST program and our Secondary Science Books. The results of this study are as follows ; 1. FAST has 226 tasks of the Inquiry Activities, which is analyzed over two times than our text. 2. In level one, FAST holds the parts of Synthesizing Results and Evaluation, Hypothesizing and Designing an Experiment but u.ese aren't found in our text. 3. In level two, our text is analyzed No Discussion 72.2%, Demonstrating or Verifying the Content of the Text 82%, but FAST has Discussion Guided 81.8%, and isn't found any tesk of Demonstrating or Verifying the Content of the text. 4. In level three, our text is exposed a typical type I and analyzed Inquiry Index 15-25 ( Middle ), but FAST is found type IV, excepting Manipulating Apparatus and Observation and analyzed Inquiry Index over 35 ( Very - High ). Therefore, FAST Program is proved to be the desirable Inquiry Science Curricular Materials. In future, this worker is to arrange the results of the following paper as follows ; 1. The verification of the FAST Program by means of the Integrated Science Curricular Materials. 2. The development of the Inquiring, Integrated Science Curricular Materials through the results of the preceding study.

• Journal of Korean Society of Steel Construction
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• v.11 no.2 s.39
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• pp.181-190
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• 1999

The objective of this study is to investigate the structural behavior of the composite slabs with the new-shaped deckplate. In order to examine the deckplate as structural members, the composite slabs with new-shaped deckplate are compared and verified with the international design codes, and the simple inertia-moment equation of the composite slabs is suggested from the regression analysis of the results of the experiments. Besides, the finite element analysis was added on the purpose of the observation of structural behavior of the section items such as the Locking rib and the Dovetail. 36 experiments of composite slabs were performed with two new-type deckplates. And the finite-element analysis was performed by ABAQUS package with the function of the 3-dimension solid modeling.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.4
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• pp.462-472
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• 1999

De-NOx facility using Selective Catalytic Reduction method is the most widely applied one that removes NOx from flue gas emitted from combustion facility such as boiler for power generation engine incinerator etc. Reductant $NH_3\;or\;NH_4OH$ is sprayed into flue gas to convert NOx into $H_2O$ and $N_2.$ Good mixing between flue gas and $NH_3$ is the most important factor to increase reduction in catalytic layer and to reduce unreacted NH3 slip. Therefore the development of mixer device for mixing effect is one of the important part for SCR facility. Objectives of this study are to investigate the relation between flow and concentration field by observation at the wake of delta-wing type mixer. At the first stage qualitative measurement of flow field is conducted by flow visualization using laser light sheet in lab. scale wind tunnel. Also we have conducted the quantitative analysis by comparing flow field measurement using LDV with numerical simulation. On the basis of qualitative and quantitative analysis we investigate the dis-tribution of flow and concentration in flow model facility. The results of an experimental and compu-tational examination of the vortex structures shed from delta wing type vortex generator having $40^{\circ}$ angle of attack are presented, The effects of vortex structure on the gas mixing is discussed, too.

• Journal of architectural history
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• v.13 no.4 s.40
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• pp.125-138
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• 2004

Open-rectangular plan Hanok is one of the major types that compose the urban tissues of Bukchon, a typical traditional residential area in Seoul. Through the comparison of the cadastral map of 1912 and the aerial photograph of 1962, the paper has given the outline of the and the distribution of Open-rectangular plan Hanok at Bukchon. And the paper defines the characteristics of Open-rectangular plan Hanok at Bukchon as followings. First, Open-rectangular plan Hanok at Bukchon is the mutated type of Open-rectangular plan Hanok in Kyong-gi Province. Second, the composition and characteristics of Bakat-chae and outer-courtyard have been changed through the adaptation itself to the compact lots of urban neighborhood. Third, the composition and characteristics of An-chae has not been changed except the inner corner bay, that gives the lights and view to An-bang through the window. And the comparison and observation of four examples, the paper defines the identities of Open-rectangular plan Hanok at Bukchon. The partial transformation comes from the conflicts and adjustments with the structure of alley and the topographical condition of lots.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.660-670
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• 2009

Neighboring construction becomes mainstream of Ground excavation in downtown area. This causes the displacement, deformation, stress condition, etc of the ground surroundings. Therefore Neighboring construction have an effect on Neighboring structure. All these years a lot of Neighboring construction carried out, and the accumulation of technology also get accomplished. But earth retaining structure collapse happens yet. Types of earth retaining structure collapse are 12. 1. Failure of anchor or strut system, 2. Insufficiency of penetration, 3. H-pile Failure on excessive bending moment, 4. Slope sliding failure, 5. Excessive settlement of the back, 6. Deflection of H-pile, 7. Joint failure of coupled H-pile, 8. Rock failure when H-pile penetration is rock mass, 9. Plane arrangement of support systems are mechanically weak, 10. Boiling, 11. Heaving, 12. Over excavation. But field collapses are difficult for classification according to the type, because collapse process are complex with various types. When we consider the 12 collapse field, insufficient recognition of ground condition is 4 case. Thorough construction management prevents from fault construction. For limitations of soil survey, It is difficult to estimate ground condition exactly. Therefore, it should estimate the safety of earth retaining system, plan for necessary reinforcement, according to measurement and observation continuously.