• Journal of the Korean Geosynthetics Society
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• v.12 no.4
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• pp.87-98
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• 2013

This study was performed a series of the isotropic compression-expansion tests and the drained triaxial tests with various the relative densities 40%, 60%, 80% and 95% for bottom ash. Using the tests results the characteristic of the parameters of Lade's single hardening constitutive model were investigated. The soil parameters Kur and n representing elastic behavior are not much affected by the change of the relative density. The other parameters such as failure criterion(m, ${\eta}_1$), hardening function(c, p) and plastic potential(${\psi}_2$, ${\mu}$) are in a positive linear relationship with the relative density. Since the soil parameters h and ${\alpha}$ representing yield function do not change much to the change of relative density and also closely related to failure criterion, they can be replaced by failure criterion ${\eta}_1$. We also observed that predicted values from the Lade's single hardening constitutive model were well consistent with the observed data.

• Bulletin of the Society of Naval Architects of Korea
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• v.19 no.2
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• pp.33-39
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• 1982

It is one of the basic problems of naval architecture and ocean engineering how to describe the wave kinematics normally under the assumption of an ideal fluid. At present, there are many wave theories available for design purposes. These can be classified into two groups: One is the analytic theory and the other is the numerical theory. This paper briefly introduces the stream function method of R.G. Dean which belongs to the latter group and shows its numerical evaluations exemplified for two cases: One is applied to observed waves and the other is for design waves. In the former case, the wave profiles are calculated by the stream function method and compared with those of the observed waves and also with the results of R.G. Dean. They show good agreement. In the latter case, the wave kinematics and wave loads on a column of diameter 1m are calculated by the stream function method and these are compared with those resulted from the 5th-order gravity wave theory. As a result of comparison the values by the stream function method are slightly larger than those by the 5th-order gravity wave theory but the difference are negligible. From this it is concluded that the stream function method is very useful. And as characteristics of the numerical theories, the stream function method of R.G. Dean can be easily extended to the higher order terms and can include easily the current velocity and the pressure distribution on the free surface. In addition, when the data of observed wave profile are given, this method can reproduced the observed wave profile as closely as possible so that this method seems to describe the ocean wave more realistically. And from standpoint of a mathematical principle the stream function method exactly satisfies the kinematic free-surface boundary condition.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.38 no.5
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• pp.509-517
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• 2001

Full-search algorithm requires large amount of computation which causes time delay or very complex hardware architecture for real time implementation. In this paper, we propose a fast motion estimator based on bit-plane matching, which reduce the computational complexity and the hardware cost. In the proposed motion estimator, the conventional motion estimation algorithms are applied to the binary images directly extracted from the video sequence. Furthermore, in the proposed VLSI motion estimator, we employ a Pair of processing cores that calculate the motion vector continuously By controlling the data flow in a systolic fashion using the internal shift registers in the processing cores, we avoid using SRAM (local memory) so that we remove the time overhead for accessing the local memory and adopt lower-cost fabrication technology. We modeled and tested the proposed motion estimator in VHDL, and then synthesized the whole system which has been integrated in a 0.6-$\mu$m triple-metal CMOS chip of size 8.15 X 10.84$\textrm{mm}^2$.

• Journal of the Korea Concrete Institute
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• v.16 no.5 s.83
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• pp.597-604
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• 2004

This work involves quantitatively investigating the correlation between reductions in strength and variations in pore structure under high temperature that can be utilized as estimation for predicting the inner temperature of member damaged by fire. The experimental results were remarkedly affected by micro-filling effect of silica fume and the different water-binder ratios. The increase of the exposure temperature caused the increase of porosity, which resulted from the reason that evaporable water in gel pore or capillary pores as well as chemically bound water was eliminated from hardened cement paste due to the dehydration of C-S-H and $Ca(OH)_2$. Thermal shrinkage of hardened cement paste gives rise to micro-crack, which cause the increase of porosity. Based on the experimental result that the increase of porosity is in charge of exposure temperature, how porosity is distributed can predict temperature-time history and assess the performance of concrete damaged by fire.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.3
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• pp.64-72
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• 2004

The research was carried out to define the environmental characteristics and vegetation structure of the evergreen fern habitat in Jejudo. The growth conditions of evergreen fern in various habitats was surveyed, including topographical features, vegetation structure, air temperature, humidity, intensity of light, water content and organic matter content in the soil. In the direction of the native habitat, 70% of research area was located in the southeast-facing slopes, 30% was located in southern slopes. The gradient ranged from $0^{\circ}$ to $30^{\circ}$. Temperature ranged from $16^{\circ}C$ to $28^{\circ}C$, and $22.3^{\circ}C$ was the average. Humidity ranged from 20 to 68%, and 36% was the average. In the native habitat, the highest light intensities reached 60,000 to 80,0001ux, but in general ranged from 300 to 40001ux. Water content in the soil ranged from 32% to 59%, organic matter content ranged from 8 to 13%. Within a unit of 25$m^2$, there were tall-tree layer such as Quercus galuca and Castanopsis cuspidata with a covering of rate 40~80%, a sub-tall-tree layer such as Camellia japonica, Staphylea bumalda and Sambucus williamsii with the covering rate of 3~5%, a shrub layer with the covering rate of 5~20%, and a grass layer with the covering rate of 40~95%. This research provides the basic data about the native habitat environment of the evergreen fern plant. Continuous monitoring and accumulation of data is necessary for the use of evergreen fern as vegetation materials.

• Archives of design research
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• v.14 no.4
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• pp.209-216
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• 2001

The purpose of this study was to find out the characteristics of the floor plans of luxurious row-houses. The examined objects were 135 floor plans with the individual exclusive space of 50 pyung or more which collected from the solicitations for sale or the magazines of architecture, housing, or interiors. The major findings were summarized as follows: First, it is revealed that as the floor size become bigger, the appropriate additional spaces such as second family room, lounge hobbyroom and Atelier are formed instead of increasing room size. Second, it is revealed that the L- DK type was the most common in LDK system. Third, it is revealed that the master's zone composed generalized layout of 4 sections such as bedroom, sittingroom, bathroom, dressingroom. Fourth, it is revealed that the multifunctional room exist as a individual space located next to the kitchen. It used to be a post of rear balcony.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.1
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• pp.82-92
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• 2010

Removal rates of NO3-N and TN in a free water surface wetland system during emergent plant growing season and non-growing were investigated. The system was established on floodplain in the down reach of the Gwangju Stream in 2008. Its dimensions were 46 meters in length and 5 meters in width. Typha angustifloria L. growing in pots about two years were planted on the half area of the system and Zizania latifolia Turcz on the other half. Water of the stream was funneled into it by gravity flow and its effluent was discharged back into it. Volumes and water quality of inflow and outflow were analyzed from October 2008 to September 2009. Inflow into the system averaged approximately 715 $m^3$/day and hydraulic residence time was about 1.5 hr. Average influent and effluent $NO_3$-N concentration was 3.37 and 2.74 mg/L, respectively and $NO_3$-N retention amounted to 18.7%. Influent and effluent TN concentration averaged 4.67 and 3.69 mg/L, respectively and TN abatement reached to 20.9%. $NO_3$-N removal rate (%) during plant growing season ($22.67{\pm}3.70$, mean ${\pm}$ standard error) was significantly high (p<0.001) when compared with that during plant non-growing one ($15.02{\pm}3.23$). TN abatement rate (%) during plant growing season ($27.42{\pm}5.98$) was also significantly high (p<0.001) when compared with that during plant non-growing one ($13.66{\pm}3.08$).

• Journal of Korean Neurosurgical Society
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• v.57 no.1
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• pp.1-5
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• 2015

Objective : Cerebral vessels, such as intracerebral perforating arterioles isolated from rat brain, have been widely used as an ex vivo model to study the cerebrovascular function associated with cerebrovascular disorders and the therapeutic effects of various pharmacological agents. These perforating arterioles, however, have demonstrated differences in the vascular architecture and reactivity compared with a larger leptomeningeal artery which has been commonly implicated in cerebrovascular disease. In this study, therefore, we developed the method for studying cerebrovascular function utilizing the olfactory artery isolated from the mouse brain. Methods : The olfactory artery (OA) was isolated from the C57/BL6 wild-type mouse brain. After removing connective tissues, one side of the isolated vessel segment (approximately $-500{\mu}m$ in length) was cannulated and the opposite end of the vessel was completely sealed while being viewed with an inverted microscope. After verifying the absence of pressure leakage, we examined the vascular reactivity to various vasoactive agents under the fixed intravascular pressure (60 mm Hg). Results : We found that the isolated mouse OAs were able to constrict in response to vasoconstrictors, including KCl, phenylephrine, endothelin-1, and prostaglandin $PGH_2$. Moreover, this isolated vessel demonstrated vasodilation in a dose-dependent manner when vasodilatory agents, acetylcholine and bradykinin, were applied. Conclusion : Our findings suggest that the isolated olfactory artery would provide as a useful ex vivo model to study the molecular and cellular mechanisms of vascular function underlying cerebrovascular disorders and the direct effects of such disease-modifying pathways on cerebrovascular function utilizing pharmacological agents and genetically modified mouse models.

• Journal of Korean Society of Rural Planning
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• v.7 no.1 s.13
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• pp.37-48
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• 2001

The purpose of this study is to suggest the landscape potential index for visualizing landscape information in the conservation of hilly landscape in urban fringe. For the visual and quantitative approach to topological landscape assessment, numerical entity data of DEM(digital elevation model) were processed with CAD-based utilities that we developed and were mainly focused on analysis of visibility and visual sensitivity. Some results, with reference in assessing greenbelt area of Eodeung Mt. in Gwangju, proved to be considerable in the landscape assessment of suburban hilly landscapes. 1) Since the viewpoints and viewpoint fields were critical to landscape structure, randomized 194 points(spatially 500m interval) were applied to assessing the generalized visual sensitivity, we called. Because there were similar patterns of distribution comparing to those by 56 points and 18 Points given appropriately, it could be more efficient by a few viewpoints which located widely. 2) Regressional function was derived to represent the relationships between probabilities of visibility frequency and the topological factors(topological dominance, landform complexity and relational aspect) of target field. 3) Visibility scores of each viewpoint were be calculated by summing the visual sensitivity indices within a scene. The scores to the upper part including ridge line have been more representative to overall distributions of visual sensitivities. Also, with sum of deviations of sensitivity indices from each single point's specific index to the weighting values of view points could be estimated rotationally. 4) The deviational distributions of visual sensitivity classes in the topological unit of target field were proved to represent the visual vulnerability of the landform. 5) Landscape potential indices combined with the visual sensitivity and the DGN(degree of green naturality) were proposed as visualized landscape information distributed by topological unit.

• International Commerce and Information Review
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• v.15 no.2
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• pp.163-185
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• 2013

Chesbrough(2003, 2006) studied Open Innovation about not only IT advanced firms such as Intel or IBM, but also P&G or 3M which are traditional manufacturing firms. As West(2006) described, we can analyze open innovation in several levels such as firm level, industry level, sector, or cluster. Most of all, we could know that according to belonging industries, open innovation effect of firms are different based of technology life cycle, or modular or non modular architecture(JHJ YUN, 2010; JHJ YUN, 2009). In this research, we will study open innovation of Korea aeroplane industry. Korea Aerospace Industries, Ltd is the flagship company in Korean aeroplane industry. We will study the open innovation relationship between Korean Aerospace Industries, Ltd and supplying firms based on Case study and Interview method. Our research question is this. Do supplying firms for Korea Aerospace Industries, Ltd adopt open innovation strategy? If then, what kind of aspects do the open strategies have?