• ETRI Journal
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• 제33권4호
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• pp.537-546
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• 2011

This paper introduces an automated method for building height recovery through the integration of high-resolution satellite images and digital vector maps. A cross-correlation matching method along the vertical line locus on the Ikonos images was deployed to recover building heights. The rational function models composed of rational polynomial coefficients were utilized to create a stereopair of the epipolar resampled Ikonos images. Building footprints from the digital maps were used for locating the vertical guideline along the building edges. The digital terrain model (DTM) was generated from the contour layer in the digital maps. The terrain height derived from the DTM at each foot of the buildings was used as the starting location for image matching. At a preset incremental value of height along the vertical guidelines derived from vertical line loci, an evaluation process that is based on the cross-correlation matching of the images was carried out to test if the top of the building has reached where maximum correlation occurs. The accuracy of the reconstructed buildings was evaluated by the comparison with manually digitized 3D building data derived from aerial photographs.

• Geomechanics and Engineering
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• 제2권1호
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• pp.29-44
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• 2010

Vertical vibration tests were conducted using model footings of different size and mass resting on the surface of finite sand layer with different height to width ratios which was underlain by either rigid concrete base, under both dry and saturated condition. The effect of saturation on the damping ratio of finite sand stratum underlain by a rigid base has been verified and compared with the results obtained for the case of finite dry sand stratum underlain by the rigid base. Comparison of results of the experimental study showed that the damping in both the cases is less than 10%. The damping ratio obtained for finite saturated sand stratum is marginally lower than that obtained on finite dry sand stratum at H/B ratio of 0.5. The difference between the two cases becomes significant when the H/B ratio increases to 3.0, indicating the significant influence of soil moisture on damping ratio of foundation- soil system with increase in the thickness of the finite sand stratum. Comparison of the predicted damping ratio for a homogeneous sand stratum with the experimental damping ratio obtained corresponding to the height to width ratio of 3.0 of the finite sand stratum underlain by the rigid concrete base indicates a significant reduction in damping ratio of the foundation-soil system for both the cases.

• BioChip Journal
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• 제12권4호
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• pp.280-286
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• 2018

Hydrogel scaffolds composed of multiple components are promising platform in tissue engineering as a transplantation materials or artificial organs. Here, we present a new fabrication method for implementing multi-layered macroscopic hydrogel scaffold composed of multiple components by controlling height of hydrogel layer through precise control of ultraviolet (UV) energy density. Through the repetition of the photolithography process with energy control, we can form several layers of hydrogel with different height. We characterized UV energy-dependent profiles with single-layered PEGDA posts photocrosslinked by the modular methodology and examined the optical effect on the fabrication of multi-layered, macroscopic hydrogel structure. Finally, we successfully demonstrated the potential applicability of our approach by fabricating various macroscopic hydrogel constructs composed of multiple hydrogel layers.

• 생물환경조절학회지
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• 제26권3호
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• pp.194-200
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• 2017

본 실험은 벼 육묘장의 연중 활용을 위해 다단 재배상에서 벼 육묘판을 이용한 어린잎 채소의 적정 수확시기를 구명하고자 다단재배에서 단 위치 및 재배 일수가 생육과 품질에 미치는 영향을 알아보고자 실시되었다. 공시 작물은 배초향(Agastsche rugosa O.)과 큰다닥냉이(Lepidium sativum L.)를 사용하였고, 코코넛코이어로 충진한 벼 육묘판에 각각의 작물을 10일 육묘한 어린잎 채소를 6단 재배상($120{\times}45{\times}180cm$)의 1층 저단(지면으로부터 20cm)과 6층의 고단(지면으로부터 170cm)에 배치하였다. 공급액은 EC $1.5dS{\cdot}m^{-1}$의 배양액과 지하수를 하루간격으로 번갈아 각각 격일로 공급하였고, 하루 3회, 회당 200~400ml/tray씩 두상관수하였다. 7일 또는 14일간 재배하여 수확한 후 생육 및 항산화 함량을 분석하였다. 저단처리와 고단처리에서의 재배 기간 중 일평균 누적광량 및 온도는 $5.1{\sim}6.2MJ{\cdot}m^{-2}$, $26.5{\sim}26.6^{\circ}C$과 $9.3{\sim}9.6MJ{\cdot}m^{-2}$, $27.5^{\circ}C$로 계측되었다. 배초향의 생육(초장, 엽장, 엽폭, 엽수, 생체중)은 저단에서 14일 재배되었을 때 높았고, 고단에서 재배된 배초향의 초장은 짧고, 엽수가 감소하였다. 큰다닥냉이의 초장, 엽폭, 엽수, 생체중은 저단에서 14일 재배되었을 때 유의적으로 높았으며, 재배일수가 길어졌을 때 엽장, 엽폭, 엽수는 차이가 없었다. 배초향의 수량은 적산온도와 누적광량이 증가함에 따라 증가하였다. 큰다닥냉이의 수량은 적산 온도 증가시 증가한 반면, 누적광량에서는 감소하여 작물간 누적광량에 따른 수량에 차이를 보였다. 배초향의 폴리페놀 및 안토시아닌 함량은 고단에서 높았으며, 재배일수가 길어졌을 때 폴리페놀, 안토시아닌 및 플라보노이드 함량은 증가하였다. 큰다닥냉이의 폴리페놀 함량은 고단처리에서 높았고, 안토시아닌 및 플라보노이드 함량은 다단 위치와 재배일수에 따른 차이가 없었다. 한편 두 작물의 총엽록소 함량은 저단에서 7일 재배하였을 때 가장 높았다. 따라서 고온기 다단 재배 시 생육과 품질을 고려한 어린잎 채소 재배시 육묘 후 배초향은 고단에서 14일, 큰다닥냉이는 저단에서 7일 재배하여 수확하는 것이 좋으리라 판단한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.402-407
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• 2001

This paper reports a result of numerical heat transfer analysis for heat spreader with various ribs. Four different ribs are compared in this study. In general, the heat transfer on a vertical plate is enhanced when a rib is attached as the surface area increases, and the growth of the boundary layer is interrupted. However, for a low flow less than 0.1m/s, it is observed that the heat transfer is sensitive to the height of a rib: it decreases as the height increases. Among the four ribs, the H-shaped rib showed better performance than other ribs.

• 한국정밀공학회지
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• 제17권2호
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• pp.35-42
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• 2000

In recent years the recording density of hard disks has increased significantly largely due to the decreasing flying height. As a result of decreased flying height, the reliability issue become more critical. In this work the relationship between hard disk surface damage and data loss was investigated by using an actual hard disk drive. The purpose of this research was to identify the key factor which leads to data loss. It was shown that data loss is directly related to the physical damage of the Co-magnetic layer and there was no data loss when only carbon protective coating was damaged by the diamond tip.

• Journal of Advanced Marine Engineering and Technology
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• 제27권6호
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• pp.721-727
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• 2003

Freezing of turbulent water flow between two horizontal cooled parallel plates with the separated region has been investigated experimentally. The flow separation was induced by vertical plates (two-dimensional plates) situated at the inlet of the rectangular channel. The degree of flow separation was varied by employing vertical thin plates with various heights. Three kinds of the vertical plates with 8.0, 9.8 and 12.5 mm in height were utilized. The Reynolds number and cooling temperature ratio were ranged from $3.45\times10^3 to 1.73\times10^4$ and 7.0 to 20.0 respectively, The measurements show that the flow separation influenced remarkably on the local ice formation characteristics. The location of the first ice layer and the average heat transfer at the ice surface were found be correlated as a function of the Reynolds number, the cooling temperature ratio, and the orifice height ratio.

• 대한기계학회논문집B
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• 제23권9호
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• pp.1192-1200
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• 1999

The present study investigates flow characteristics in a cavity with one rotating disk and co-rotating disks for application to HDD. The experiments are conducted for rotating Reynolds numbers of $5.5{\times}104$ to $1.10{\times}105$ and for gap ratios of 0.059 to 0.175 in a single rotating and 0.047 to 0.094 in co-rotating disk. Time-resolved velocity components and turbulence intensity on the rotating disks are obtained by using LDA measurements. Detailed Knowledge of the flow characteristics is essential to analyze flow vibration and heat transfer and to design head-arm assembly and hub height in HDD. The results indicate that the velocity field in HDD is changed largely by the rotating Reynolds numbers and hub height of the disk.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.24.3-24.3
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• 2008

The signals transmitted from satellites of Global Navigation Satellite System (GNSS) interact with the plasma of the ionosphere. To study the impact of the ionospheric plasma on GNSS applications a comprehensive knowledge of the ionosphere is required. Especially the correct measurement of the ionosphere such as the peak height of the F2 layer peak electron density (hmF2) is important for the GNSS ionospheric model. Anyang ionosonde station ($37.39^{\circ}N$, $126.95^{\circ}E$) has been operating from October 2000 and the accumulated data for 8 years may allow us to obtain climatological characteristics of middle latitude ionospheric F region for GNSS application. We analyzed the variations of the hmF2 and NmF2 over Anyang station for different conditions of solar activity, geomagnetic activity, season, and local time, and we compared our results with the IRI model.

• Transactions on Electrical and Electronic Materials
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• 제6권5호
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• pp.225-228
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• 2005

In this work, we studied the optimized copper thickness in Cu ECP (Electrochemical Plating). In order to select an optimized Cu ECP thickness, we examined Cu ECP bulge (bump, hump or over-plating amount), Cu CMP dishing and electrical properties of via hole and line trench over dual damascene patterned wafers split into different ECP Cu thickness. In the aspect of bump and dishing, the bulge increased according as target plating thickness decreased. Dishing of edge was larger than center of wafer. Also in case of electrical property, metal line resistance distribution became broad gradually according as Cu ECP thickness decreased. In conclusion, at least $20\%$ reduced Cu ECP thickness from current baseline; $0.8\;{\mu}m$ and $1.0\;{\mu}m$ are suitable to be adopted as newly optimized Cu ECP thickness for local and intermediate layer.