• 천문학회지
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• 제47권4호
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• pp.147-152
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• 2014

We present measurements of the Fe $K{\alpha}$ emission line of the intermediate polar V1223 Sagittarii observed with the Suzaku satellite. The spectrum is modeled with an absorbed thermal bremsstrahlung spectrum and three Gaussians for the three components of the Fe $K{\alpha}$ lines. We resolve the neutral or low-ionized (6.41keV), He-like (6.70keV), and H-like (7.00keV) iron lines. We also obtain a thermal continuum temperature of 25 keV, which supports a thermal origin of the hard X-rays observed from the shock heated layers of gas between the white dwarf and the shock front. Hence, we believe that the He-like and H-like lines are from the collisional plasma. On the origin of the Fe $K{\alpha}$ fluorescence line, we find that it could be partly from reflections of hard X-rays from the white dwarf surface and the $N_H$ absorption columns. We also discuss the Fe $K{\alpha}$ emission line as veritable tool for the probe of some astrophysical sites.

• 한국환경복원기술학회지
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• 제24권3호
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• pp.19-31
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• 2021

The waste landfill that has been used as a park through a stabilization project to provide green space to local residents. Vegetation restoration is necessary for the landfill park project, but it is difficult to restore vegetation due to various disturbances in the landfill. This study analyzed the successional dynamics and ecological characteristics of Robinia pseudoacacia communities from the slopes of Noeul Park by applying the 7-stage successional hypothesis. As a result of the study, there was almost no intermediate successional stage. There are only the early successional stage which Robinia pseudoacacia has an absolute dominance of 100% in the crown and middle layers, and the degeneration successional stage which formed by the introduction of Morus alba. This result showed that the succession of Robinia pseudoacacia communities were not able to proceed to the climax forest due to various disturbances in the waste landfill. Therefore, it was analyzed that it is necessary to induce the succession through intermediate steps such as Morus alba, since it is difficult to transition from Robinia pseudoacacia community to the native Quercus spp. community.

• 방사선산업학회지
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• 제17권4호
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• pp.359-367
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• 2023

In this study, the function and purpose of the disposal cover, which is an engineering barrier installed to isolate the disposal vault of the near-surface disposal facility for radioactive waste from natural/man-made intrusion, and the design details of the demonstration facility for performance verification were described. The Demonstration facility was designed in a partially divided form to secure the efficiency of measurement while being the same as the actual size of the surface disposal facility to be built in the Intermediate & low-level radioactive waste disposal site of the Korea Radioactive Waste Agency (KORAD). The instruments used for measurement consist of a multi-point thermometer, FDR (Frequency Domain Reflectometry) sensor, inclinometer, acoustic sensor, flow meter, and meteorological observer. It is used as input data for the monitoring system. The 3D monitoring system was composed of 5 layers using the e-government standard framework, and was developed based on 4 components: screen, control module, service module, and DBIO(DataBase Input Output) module, and connected them to system operation. The monitoring system can provide real-time information on physical changes in the demonstration facility through the collection, analysis, storage, and visualization processes.

• 한국해양학회지
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• 제30권3호
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• pp.147-162
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• 1995

큰 潮差 지역인 금강 鹽河口의 潮流과 江水流入에 의한 순환과 이에 따른 부유물질의 이동을 알아보기 위해 1990년부터 1992년까지 세 정점에서 潮流 및 浮游퇴적물질 농도를 관측하였다. 이 염하구의 가장 외해쪽 관측점에서는 漲潮流 와 落潮流의 수직 구조는 거의 대칭형을 나타내고 있다. 또, 남측 수로에서는 漲 潮流가 全水層을 통해서 우세하나 북측 수로에서는 상층과 저층에서는 落潮流가 우세하고 중층에서는 漲潮流가 우세하였다. 남측 수로에서의 최대유속은 漲潮流 시에 중층에서 174 cm/s이었으며, 북측 수로의 최대 유속도 漲潮流시 중층에서 148 cm/s로 기록되었다. 반면에 표층과 저층에서는 최대유속 110.6 cm/s의 강한 유속이 落潮時에, 92.1 cm/s이 漲潮시에 각각 기록되었다. Hansen and Rattray 의 scheme에 의하면 금강 鹽河口는 Type 3로 분류될 수 있다. 즉 이 鹽河口의 수층은 漲潮流에 의해서 成層化하고 高潮後의 落潮流는 수층간의 밀도차를 줄여 서 亂流化한다. 이곳의 저층 흐름은 일반적으로 난류성이다. 한 조석 週期당 부유 물질의 이동량은 潮差와 하천유량에 달려있다고 생각된다. 관측기간중 최대의 부 유물질 이동은 하천유량이 최소였던 1991년 5월중 남측 수로에서의 측정치에서 초당 20.61톤으로 나타났으며, 최소 이동은 최소 潮差 기간인 1992년 7월에 북측 수로에서 초당 0.65톤으로 나타났다. 본 연구해역의 강한 해저전단속도는 창조류 기간 동안에 해저퇴적물을 침식시키며, 상대적으로 긴 落潮 기간은 이들 부유퇴적 물을 외해쪽으로 운반시키고 있다. 정상적인 강수 유입 조건하에서는 대부분의 부유물질이 남측 수로를 통해서 운반되나 강수의 유입이 많아지는 경우에는 오히 려 북측 수로를 통한 부유물질의 이동이 더 크다.

• 한국동물학회지
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• 제31권3호
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• pp.165-176
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• 1988

안점의 꽃갯지렁이(Pseudopotamilla occelata) 난모세포의 표면의 구조적 변화를 전자현미경으로 연구하였다.일단 난소로부터 방출되어나온 직경 5 $\mu$ m정도의 난모세포가 동일한 체강액에서 직경 185 $\mu$ mR까지 성장하는 난자형성중 난모세포의 난황막은 구조적으로 변하였다. 미융모(microvilli)는 구조, 수량 및 행동에 변화를 보였다. 전난황형성기에 미융모는 길이가 짧고 두 갈래로 갈라져 있었다. 난자형성이 진행됨에 따라 미융모의 길이는 계속 증가하는 반면 수는 전난황 형성기까지만 증가하고 난황형성기는 점차 감소하는 경향을 보였다. 미융모 끝에 Glycocaiyx구조가 전난황형성초기에서부터 형성되는 것이 보이는데, 이구조는 난모세포의 성장과 함께 수적으로 점차 증가하다가 마지막 단계에서 일정하게 유지되었다. 난자형성 말기에 미융모의 수축과 동시에 미융모의 끝이 줄기로부터 분리되면서 조그만 소낭이 형성되어 난화막 표면에 남게 되었다. 난화막은 처음에는 와층(outer layer),중간층(intermediate layer),및 내층(inner layer)의 3층으로 되어있었으나, 외층과 중간층은 난자형성 전기간을 통하여 구조적으로 거의 일정하지만, 내층은 그 두께가 두터워지고 80 $\mu$m의 난모세포에서부터는 두개의 층으로 다시 나뉘어지는 것을 볼 수 있었다. 이와같은 구조적인 변화는 아마도 난모세포의 표면이 비록 동일한 환경에서 일지라도 단계에 따라 기능적으로 다르게 분화한 결과로 생각되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권8호
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• pp.1171-1175
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• 2005

An experiment was conducted (28 to 44 weeks) to study the laying performance, shell quality, and nutrient retention of White Leghorn layers fed different levels of non-phytate phosphorus (NPP). Six levels of NPP (0.15, 0.18, 0.21, 0.24, 0.27 and 0.30%) at a constant calcium (Ca) level (3.5%) in maize-soya-deoiled rice bran based diets were formulated, and each experimental diet was offered ad libitum for 16 weeks to five replicates with five birds in each replicate. The body weight of WL layers fed diet containing 0.15% NPP was significantly (p<0.05) lower than those fed diet with 0.30% NPP, at 44 weeks of age. However, the hen day egg production, egg weight, daily feed intake and feed consumed per dozen eggs were not influenced by the variation in the NPP levels in the diet. The bone ash content was significantly (p<0.05) higher in the birds fed 0.30% NPP as compared with those fed diets up to 0.24% NPP. Bone ash content was intermediate in the birds fed diet containing 0.27% NPP. The tibia strength followed the same trend as that of bone ash. Dietary NPP content had no influence on serum Ca and protein concentration and activity of alkaline phosphatase. However, serum inorganic P concentration increased linearly with NPP content in the diet. The concentration of P was significantly (p<0.05) higher in the birds fed 0.27% NPP or higher as compared with those fed 0.15% NPP. Levels of dietary NPP had no influence on egg quality parameters like shell wt, shell thickness, shell strength and specific gravity. The retention of nutrients such as DM, N and Ca were comparable among the WL layers fed different levels of NPP. However, the retention of P decreased linearly with increase in the level of NPP in the diet. The retention of P in the birds fed diets up to 0.24% NPP in the diet was comparable, however further increasing the content of NPP (either 0.27% or 0.30%) reduced the retention of P. Based on the results of the present study, 0.15% NPP (180 mg/b/d) in the diets of WL layers is adequate for optimum production performance during 28 to 44 weeks of age, however, WL layers require 0.27% NPP (324 mg /b/d) in the diet for optimum production with better bone mineralization.

• 한국도로학회논문집
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• 제17권1호
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• pp.51-58
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• 2015

PURPOSES : The objective of this study is to compare the densities of asphalt pavements measured both in the field and in the laboratory, and also to evaluate the applicability of field density measuring equipment, such as the pavement quality indicator (PQI), by using statistical analysis. METHODS : For the statistical analysis of the density measured from asphalt pavement, student t-tests and a coefficient of correlation are investigated. In order to compare the measured densities, two test sections are prepared, with a base layer and an intermediate layer constructed. Each test section consists of 9 smaller sections. During construction, the field densities are measured for both layers (base and intermediate) in each section. Core samples are extracted from similar regions in each section, and moved to the laboratory for density measurements. All the measured densities from both the field and laboratory observations are analyzed using the selected statistical analysis methods. RESULTS AND CONCLUSION : Based on an analysis of measured densities, analysis using a correlation coefficient is found to be more accurate than analysis using a student t-test. The correlation coefficient (R) between the field density and the core density is found to be very low with a confidence interval less than 0.5. This may be the result of inappropriate calibration of the measuring equipment. Additionally, the correlation coefficient for the base layer is higher than for the intermediate layer. Finally, we observe that prior to using the density measuring equipment in the field, a calibration process should be performed to ensure the reliability of measured field densities.

• 한국표면공학회지
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• 제30권4호
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• pp.272-280
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• 1997

The Thermal Barrier Coation(TBC) to improve the that barrier and wear resistant propenrty in high temperature ofthe aircraftength between the accumlation of the aircraft engine and the automobile engine has usually the two layer structure. One is a creamic top layer for heat insulation and the other is a metal bond layer to facilitate the bond strength between the top ceramic layer and the substrate. But, the coated layers should be peeled off because of the accumulation of the thermal stress by the differance of the thermal expantion coefficient between metal and ceramics in a hrat cyclic environment. In this study, the intermediate layer by plasm spray process was introduced to reduce the thermal stress. The powders of plasm spray coating were the Yttria Stabilized Zirconia (YSZ), the Magnesia Stabillized Zirconia(MSZ) and NiCrAlY. the intermediate layer was sprayed with the powders of the bond cast for the purpose of test were executed. The high temperature wear resistance tends to decreasnceee wear and thermal shock test were exeucuted. The high temperature were resistance of the YSZ TBC is better that of the MSZ TBC. The wearrsistance tends to decrease accoring to incresing the temperature between $400^{\circ}C$to $600^{\circ}C$. The thermal shock life of the 3 layer TBC with YSZ top casting was the most outstanding thermal shock rsisstasnce. This means that the intermediate layer should play an importnat roll to alleviate the diffrerence of the thermal expansion coef frcients between metallic layer and cermics layer.

• 대한전자공학회논문지SP
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• 제39권2호
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• pp.107-115
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• 2002

본 논문은 한 쌍의 스테레오 영상으로부터 BDM(Bidirectional Disparity Morphing)을 이용하여 중간시점 영상을 보간하는 방법을 제안한다. 영상은 하나 이상의 계층으로 구성되어 있고 각각의 계층은 유사한 시차값을 갖기 때문에, 블록 단위의 시차 맵을 이용하는 것은 유용하다. 또한 블록 단위의 시차 맵은 시차계산을 위한 영상의 해상도를 줄여 계산량을 크게 감소시킨다. 그러나 서로 다른 계층이 겹쳐진 영역에서는 시차가 급격히 변화하여 정합 오차가 증가하고, 가려짐이 발생할 확률이 높다. 따라서 정합 결과에 따라 블록의 크기를 변화시켜 보다 정밀하게 대응 블록을 검색하여 잘못된 시차 계산을 막고, 아울러 가려진 영역을 검출할 수 있다. 가려진 영역의 시차는 가려짐 패턴을 이용하여 올바른 시차를 지정할 수 있어, 결과적으로 보다 정확한 중간 시점 영상을 생성할 수 있다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권5호
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• pp.39-48
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• 2021

Analysis of the change in water content and distribution was conducted according to the supply of recirculation water to a landfill. An excavation sample analysis showed that the recirculation water injection zone had water content 8.8% point higher than that of the non-injection zone, after 8 months of operation. And due to the influence of recirculation water supply by vertical wells in injection zones, the water content increases along with depth more clearly than non-injection zone. According to an electrical specific-resistivity survey after 13 months of operation, the water content got higher towards the bottom of the landfill. The water transmission coefficient is 8.72×10^-4 cm/sec for injection zones and 3.36×10^-5 cm/sec for the intermediate cover layer; analysis shows that the intermediate cover layer may affect the penetration velocity of water supplied by the horizontal injection tube. For the scientific design and operation of re-injection facilities, it was deemed necessary to follow-up research on the residence time and behavior of re-injection water considering the ratio of recirculation water supply in horizontal and vertical tubes, and pitcher coefficient of intermediate and waste layers.