• Journal of the Korea Concrete Institute
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• v.26 no.2
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• pp.181-188
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• 2014

In this study, an interactive analysis considering column-pile interaction is performed on the basis of an equivalent base spring model for supplementing virtual fixed point design of bent pile structures. Through this analytical method, the application of the minimum steel reinforcement ratio of the pile (0.4%) is analyzed by taking into account the major influencing parameters. Furthermore, the limit depth for steel reinforcement ratio is proposed through the relationships between column and pile conditions. To obtain the detailed information, it is found that an interactive analysis is intermediate in theoretical accuracy between the virtual fixed point model analysis and full-modeling analysis. Base on this study, it is also found that the maximum bending moment is located within cracking moment of the pile when material nonlinearity is considered. Therefore, the minimum steel reinforcement ratio is appropriately applicable for the optimal design of bent pile structures. Finally, the limit depth for steel reinforcement ratio ($L_{As=x%}$) is proposed by considering the field measured results. It is shown that the normalized limit depth ratio for steel reinforcement ratio ($L_{As=x%}/L_P$) decreases linearly as the length-diameter ratio of pile ($L_P/D_P$) increases, and then converges at a constant value.

• Radiation Oncology Journal
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• v.6 no.1
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• pp.85-91
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• 1988

For the physical characterization of neutron beam, dosimetric measurements had been performed to obtain physical data of KCCH cyclotron-produced neutrons for clinical use. The results are presented and compared with the data of other institutions from the literatures. The central axis percent depth dose, build-up curves and open and wedge isodose curve values are intermediate between that of a 4 and 6 MV X-rays. The build-up level of maximum dose was at 1.35cm and entrance dose was approximately $40\%$. Flatness of the beam was $9\%$ at Dmax and less $than{\pm}3\%$ at the depth of $80\%$ isodose line. Penumbra begond the $20\%$ line is wider than corresponding photon beam. The output factors ranged 0.894 for $6\times6cm$ field to 1.187 for $30\times30cm$ field. Gamma contamination of neutron beam was $4.9\%$ at 2 cm depth in $10\times10cm$ field.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.6
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• pp.1312-1317
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• 2012

ZSphere of ZBrush can be added to the canvas, and most of all, added to the existing ZSphere as mobile geometrical objects. For example, arms can be produced out of the globoid in the progress of an intermediate step. characters with multiple limbs can be produced easily in this way. With Zsphere, several Child Spheres can be produced out of single Sphere, then these can be parents spheres, and can connect other Child Spheres. In this paper, by making each form through these processes, 3D characters were modeled to shape easily and rapidly. Since 3D objects can be added, rotated, and moved, they can interact smoothly with Z-depth of campus. To place these objects on the screen, paint, build fixed perspective image, smerge pixols and transform 3D objects, diverse transforming tools and sculpturing tools were used. The characters were designed in the way that first, the finished 3D characters were transformed into poly, then each side was restructured rapidly with Topology.

• The Journal of the Korea Contents Association
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• v.17 no.8
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• pp.226-240
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• 2017

The purpose of this study is to explore in depth what is the identity of the community foundation, how it operates, and what difficulties it faces. For this purpose, this study conducted in-depth interviews with 5 practitioners working in community foundations. The results of the study are as follows. First, it is important for the participants to identify what their organizations are doing for the community rather than to distinguish them by their legal status. Second, community foundations recognize fundraising as an important achievement regardless of the type. Third, community foundations have experienced difficulties in raising funds, establishing community foundation identity, relationship with other nonprofit organizations in the area, citizen participation, organizational capacity and institutional instability. Therefore, as a policy alternative for community foundations, this study suggested that the establishment of identity and model of community foundation suited to Korean situation, the enhancement of capacity as intermediate support organizations, and the administrative and institutional support of government.

• Ocean and Polar Research
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• v.30 no.3
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• pp.277-287
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• 2008

We collected information on seasonal and interannual variability of surface chlorophyll a concentration between 1997-2007 from the Northwest Pacific Ocean. Satellite data were used to acquire chlorophyll a and sea surface temperature from six regions: East Sea/Ulleung Basin, East China Sea, Philippin Sea, Warm Pool region, Warm Pool North region, and Warm Pool East region. Mixed layer depth (MLD) was calculated from temperature profiles of ARGO floats data in four of the six regions during 2002-2007. In the East Sea/Ulleung Basin, seasonal variability of chlorophyll a concentration was attributed to seasonal change of MLD, while there was no significant relationship between chlorophyll a concentration and MLD in the Warm Pool region. Interannual anomaly in sea surface temperature were similar among the East Sea, East China Sea, Philippin Sea, and Warm Pool North region. The anomaly pattern was reversed in the Warm Pool East region. However, the anomaly pattern in the Warm Pool region was intermediate of the two patterns. In relation to chlorophyll a, there was a reversed interannual anomaly pattern between Warm Pool North and Warm Pool East, while the anomaly pattern in the Warm Pool region was similar to that of Warm Pool North except for the El $Ni\tilde{n}o$ years (1997/1998, 2002/2003, 2006/2007). However, there was no distinct relationship among other seas. Interestingly, in the Warm Pool and Warm Pool East regions, sea surface temperature showed a pronounced inverse pattern with chlorophyll a. This indicates a strong interrelationship among sea surface temperature-MLD-chlorophyll a in the regions. In the Warm Pool and Warm Pool East, zonal distribution of chlorophyll a concentration within the past 10 years has shown a good relationship with sea surface temperature which reflects ENSO variability.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.3
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• pp.341-349
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• 2010

It is well known that manganese is hard to oxidize under neutral pH condition in the atmosphere while iron can be easily oxidized to insoluble iron oxide. The purpose of this study is to identify removal mechanism of manganese in the D water treatment plant where is treating bank filtered water in aeration and rapid sand filtration. Average concentration of iron and manganese in bank filtered water were 5.9 mg/L and 3.6 mg/L in 2008, respectively. However, their concentration in rapid sand filtrate were only 0.11 mg/L and 0.03 mg/L, respectively. Most of the sand was coated with black colored manganese oxide except surface layer. According to EDX analysis of sand which was collected in different depth of sand filter, the content of i ron in the upper part sand was relatively higher than that in the lower part. while manganese content increased with a depth. The presence of iron and manganese oxidizing bacteria have been identified in sand of rapid sand filtration. It is supposed that these bacteria contributed some to remove iron and manganese in rapid sand filter. In conclusion, manganese has been simultaneously removed by physicochemical reaction and biological reaction. However, it is considered that the former reaction is dominant than the latter. That is, Mn(II) ion is rapidly adsorbed on ${\gamma}$-FeOOH which is intermediate iron oxidant and then adsorbed Mn(II) ion is oxidized to insoluble manganese oxide. In addition, manganese oxidation is accelerated by autocatalytic reaction of manganese oxide. The iron and manganese oxides deposited on the surface of the sand and then are aged with coating sand surface.

• Journal of Broadcast Engineering
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• v.25 no.5
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• pp.655-664
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• 2020

Free viewpoint image synthesis technology is one of the important technologies in the MPEG-I (Immersive) standard. RVS (Reference View Synthesizer) developed by MPEG-I and in use in MPEG group is a DIBR (Depth Information-Based Rendering) program that generates an image at a virtual (intermediate) viewpoint from multiple viewpoints' inputs. RVS uses the mesh surface method based on computer graphics, and outperforms the pixel-based ones by 2.5dB or more compared to the previous pixel method. Even though its OpenGL version provides 10 times speed up over the non OpenGL based one, it still shows a non-real-time processing speed, i.e., 0.75 fps on the two 2k resolution input images. In this paper, we analyze the internal of RVS implementation and modify its structure, achieving 34 times speed up, therefore, real-time performance (22-26 fps), through the 3 key improvements: 1) the reuse of OpenGL buffers and texture objects 2) the parallelization of file I/O and OpenGL execution 3) the parallelization of GPU shader program and buffer transfer.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.27 no.5
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• pp.345-352
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• 2015

Two-dimensional hydraulic model experiments on vertical structures were conducted to investigate wave transmission characteristics under irregular wave condition. The formula about transmission coefficient for the vertical structure was suggested and the results were compared with Goda(1969). Since Goda(1969)'s tests were conducted based on regular waves, the results showed the discrepancy with this study. The Goda's results were relatively higher than the results from the present study. An influence parameter was quantitatively suggested in this study to consider the effect of structural design factors such as the width of structures, the water depth, and the wave length on the wave transmission, while Goda(1969) suggested the mean, upper and lower limits of parameters for the vertical wall(d=h). The transmission coefficients and energy conservation for zero-freeboard conditions were analyzed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.303-306
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• 2006

Using a variety of chemical geothermometers we estimate the temperature of a deep geothermal reservoir in relation to thermal groundwater in the Bugok area, southern Korea, in order to assess the potential use of geothermal energy in South Korea. Thermal water at Bugok has been exploited down to about 400 m below the land surface and shows the highest outflow temperatures (up to $78{\circ}C$) in South Korea. Based on the hydrochemical data and occurrence, groundwater in Bugok can be classified into three groups: $Na-SO_4$ type thermal groundwater (CTGW) occurring in the central part (about 0.24 $km^2$) $Ca-HCO_3$ type cold groundwater (SCGW) occurring in shallow peripheral parts of CTGW; and the intermediate type groundwater (STGW). CTGW waters are typical of thermal water in the area, because they have the highest outflow temperatures and contain very high concentrations of Na, K and $SiO_2$ due to the sufficient reaction with silicate minerals in deep reservoir. Their enriched $SO_4$ was likely formed by gypsum dissolution. The major ion composition of CTGW shows the general approach to a partial equilibrium state with rocks at depth. The application of various alkali ion geothermometers yields temperature estimates in the range of 88 to $198{\circ}C$ for the thermal reservoir. Multiple mineral equilibrium calculation indicates asimilar but narrower temperature range between about 100 and $155{\circ}C$. These temperature estimates are not significantly higher than the measured outflow temperatures for CTGW Considering the heat loss during the ascent- of thermal waters, this fact may suggest that a thermal reservoir in the study area is likely located at relatively shallow depths (possibly close to the depth of preexisting wells). Therefore, we suggest a high potential for geothermal energy development around the Bugok area in southern Korea.

• Journal of the Korea Computer Graphics Society
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• v.16 no.4
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• pp.1-10
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• 2010

We present a method to reproduce in-between views from captured stereo images to control depth feeling that a user can perceive on a 3D display. The stereo images captured from a pair of cameras have a fixed viewpoint and a screen parallax which depend on the physical position and the distance between the cameras. In this paper, we produce stereo images of an intermediate viewpoint between two original cameras by a view interpolation on the input stereo images. Furthermore, the camera separation of the reproduced stereo images can be controlled by a linear interpolation coefficient used by the view interpolation. By using the proposed method, stereo images can be reproduced where the depth feeling and a three dimensional effect is suitable for the individual's eye separation or the characteristic of an application.