• Proceedings of the Korean Geotechical Society Conference
• /
• 1991.10a
• /
• pp.87-102
• /
• 1991

It has been reported that the failure of Carsington Dam in Eng1and occured due to the existence of a thin yellow clay layer which was not identified during the design work, and due to pre-existing shears of the clay layer. The slope stability analyses during the design work, which utilized traditional circular arc type failure method and neglected the existence of the clay layer, showed a safety factor of 1.4. However, the post-failure analyses which utilized translational failure mode considering the clay layer and the pre-existing shear deformation revealed the reduction of safety factor to unity. The post-failure analysis assumed 10。 inclination of the horizontal forces onto each slice based on the results of finite element analyses. In this paper, Bishop's simplified method, Janbu method, and Morgenstern-Price method were used for the comparison of both circular and translational failure analysis methods. The effects of the pre-existing shears and subsquent movement were also considered by varying the soil strength parameters and the pore pressure ratio according to the given soi1 parameters. The results showed factor of safefy 1.387 by Bishop's simplified method(STABL) which assumed circular arc failure surface and disregarding yellow clay layer and pre-failure material properties. Also the results showed factor of safety 1.093 by Janbu method(STABL) and 0.969 by Morgenstern-Price method(MALE) which assumed wedge failure surface and considerd yellow clay layer using post failure material properties. In addition, dam behavior was simulated by Cam-Clay model FEM program. The effects of pore pressure changes with loading and consolidation, and strength reduction near or at failure were also considered based on properly assumed stress-strain relationship and pore pressure characteristics. The results showed that the failure was initiated at the yellow clay layer and propagated through other zones by showing that stress and displacement were concentrated at the yel1ow clay layer.

• Journal of Bio-Environment Control
• /
• v.27 no.2
• /
• pp.140-146
• /
• 2018

This research was conducted to determine the influence of incorporation levels of sulfur into a coir dust+pine bark medium (1:1, v/v) on the changes in the bicarbonate ($HCO_3{^-}$) concentrations and pH of soil solution, crop growth, and nutrient uptake of 'Ssanta' strawberry. In the preparing of the mixed medium, sulfur powder was added with the rate of 0 (control), 0.23, 0.45, 0.90, and $1.80g{\cdot}L^{-1}$ and Hoagland nutrient solution containing $240mg{\cdot}L^{-1}$ $HCO_3{^-}$ was supplied during the crop cultivation. The growth measurements and tissue analysis for the determination of nutrient contents were carried out 140 days after solution application and the soil solution analysis was performed every two weeks. As the level of sulfur was elevated, the overall growth of mother plants became better showing that the growth indexes except chlorophyll contents were the lowest in control treatment but the statistical differences were not found among the three treatments of $0.45g{\cdot}L^{-1}$ or higher sulfur. The higher the levels of sulfur incorporation, the higher the occurrence of runners and the growth of daughter plants. The length of the runners and the number of daughter plants occurred per mother plants were higher in the treatments of 0.90 and $1.80g{\cdot}L^{-1}$ than the three treatments of 0, 0.23, and $0.45g{\cdot}L^{-1}$, but the statistical differences were not observed between the 0.90 and $1.80g{\cdot}L^{-1}$ treatments. The rose of pH and $HCO_3{^-}$ concentrations in soil solution of root media continued all the cropping period, but those decreased slightly in the treatments of $0.90g{\cdot}L^{-1}$ or higher. The soil solution concentrations of $K^+$ and $PO_4{^3-}$ in the treatments of 0.90 and $1.80g{\cdot}L^{-1}$ was lower than those in other treatments and the statistical differences in the $Ca^{2+}$ and $Mg^{2+}$ concentrations were not observed among all treatments. The nutrient contents in tissue analyzed in this experiment were the lowest in the control treatments and those increased as incorporation rates of sulfur were elevated. Above results indicated that when 'Ssanta' strawberry is grown hydroponically and the root medium is coir dust and the pine bark (5:5, v/v) mix, the sulfur incorporation rate as pre-planting fertilizer has to be higher than $0.9g{\cdot}L^{-1}$ root medium to reduce the $HCO_3{^-}$ injury.

• Journal of Bio-Environment Control
• /
• v.27 no.2
• /
• pp.173-179
• /
• 2018

Investigation of the optimum levels of pre-plant nitrogen for raising of hot pepper (cv. Nokkwang) plug seedlings was the objective of this research. To achieve this, the pre-plant nitrogen levels were varied to 0, 100, 250, 500, 750, 1,000, and $1,500mg{\cdot}L^{-1}$ and the other essential nutrients were controlled to equal concentrations in all treatments. All the fertilizers were added during the formulation of the mixed medium of coir dust, peatmoss, and perlite with the ratio of 35, 35, and 30% (v/v/v). The root medium containing pre-plant fertilizer was packed into 50-cell plug trays and seeds were sown. The measurement of pH and EC in every week, soil solution analysis for nutrients in week 0, 3, and 7 and growth measurements as well as tissue analysis for nutrient contents in week 7 were conducted. The pHs measured before seed sowing did not show significant differences, but the differences among treatments became significant as seedlings grow bigger. The soil solution ECs were significantly different among treatments in week 0 and these differences were diminished by degrees after week 3, resulting in no significant differences among treatments in week 7. The trends in changes of $NH_4-N$, $NO_3-N$, and other the macro-element concentrations in soil solution of root media were similar to those of ECs. The treatments of 500 and $750mg{\cdot}L^{-1}$ N were more effective than other treatments on seedling growth. The seedling growths in the treatments containing higher N than $1,000mg{\cdot}L^{-1}$ and control were severely suppressed. The elevated pre-plant N concentrations in the root medium resulted in the increase of tissue N contents. The treatments of 500 and $750mg{\cdot}L^{-1}$ N shown the highest seedling growths had 5.13% and 5.31%, respectively, in tissue N contents based on the dry weight of above ground tissue at week 7. The results of this study indicated that the optimum level of pre-plant N is 500 to $750mg{\cdot}L^{-1}$ for the raising of hot pepper plug seedlings.

• Archives of design research
• /
• v.20 no.3 s.71
• /
• pp.61-72
• /
• 2007

Having started with "Space War", the first game produced by MIT in the 1960's, the gaming industry expanded rapidly and grew to a large size over a short period of time: the brand new games being launched on the market are found to contain many different elements making up a single content in that it is often called the 'the most comprehensive ultimate fruits' of the design technologies. This also translates into a large increase in the number of things which need to be considered in developing games, complicating the plans on the financial budget, the work force, and the time to be committed. Therefore, an approach for analyzing the elements which make up a game, computing the importance of each of them, and assessing those games to be developed in the future, is the key to a successful development of games. Many decision-making activities are often required under such a planning process. The decision-making task involves many difficulties which are outlined as follows: the multi-factor problem; the uncertainty problem impeding the elements from being "quantified" the complex multi-purpose problem for which the outcome aims confusion among decision-makers and the problem with determining the priority order of multi-stages leading to the decision-making process. In this study we plan to suggest AHP (Analytic Hierarchy Process) so that these problems can be worked out comprehensively, and logical and rational alternative plan can be proposed through the quantification of the "uncertain" data. The analysis was conducted by taking FPS (First Person Shooting) which is currently dominating the gaming industry, as subjects for this study. The most important consideration in conducting AHP analysis is to accurately group the elements of the subjects to be analyzed objectively, and arrange them hierarchically, and to analyze the importance through pair-wise comparison between the elements. The study is composed of 2 parts of analyzing these elements and computing the importance between them, and choosing an alternative plan. Among these this paper is particularly focused on the Delphi technique-based objective element analyzing and hierarchy of the FPS games.

• Archives of design research
• /
• v.18 no.4 s.62
• /
• pp.257-266
• /
• 2005

The purpose of this study is to investigate the psychological reaction to the image of the worship space in the church buildings and to quantify its contribution of the stimulation elements causing such reaction, and finally to suggest basic data for realizing emotional worship space of the church architecture. For this, 143 christians were surveyed to analyze the relationship between 23 emotional expressions extracted from the worship space and 32 images of the worship space. The combined data was described with the two dimensional dispersion using the quantification theory III. The analysis found out that 'simplicity-complexity' of the image consisted of the horizontal axis (the x-axis) and 'creativity' of the image the vertical axis(the y-axis). In addition, to extract the causal relationship between the value of emotional reaction and its stimulation elements quantitatively, the author indicated 4 emotional word groups such as simple, sublime for x-axis and typical creative for y-axis based on its similarity by the cluster analysis, The quantification theory I was also used with total value of equivalent emotional words as the standard variance and the emotional stimulation elements of the worship space as the independent variance. 9 specific examples of the emotional stimulation elements were selected including colors and shapes of the wall and the ceiling, shapes and finish of the floor materials, window shapes, and the use of the symbolic elements. Furthermore, 31 subcategories were also chosen to analyse their contribution on the emotional reaction. As a result, the color and finish of the wall found to be the most effective element on the subjects' emotional reaction, while the symbolic elements and the color of the wall found to be the least effective. It is estimated that the present study would be helpful to increase the emotional satisfaction of the users and to approach a spatial design through satisfying the types and purposes of the space.

• Journal of Korean Society of Forest Science
• /
• v.81 no.4
• /
• pp.363-371
• /
• 1992

This study was aimed at developing a computer model to determine rational road networks in mountainous forests. The computer model is composed of two major subroutines for digital terrain analyses and route selection. The digital terrain model(DTM) provides various information on topographic and vegetative characteristics of forest stands. The DTM also evaluates the effectiveness of road construction based on slope gradients. Using the results of digital terrain analyses, the route selection subroutine, heuristically, determines the optimal road layout satisfying the predefined road densities. The route selection subroutine uses the area-partitioning method in order to fully of roads. This method leads to unbiased road layouts in forest areas. The size of the unit partitiones area can be calculated as a function of the predefined road density. In addition, the user-defined road density of the area-partitioning method provides flexibility in applying the model to real situations. The rational road network can be easily achived for varying road densities, which would be an essential element for network design of forest roads. The optimality conditions are evaluated in conjuction with longitudinal gradients, investment efficiency earthwork quantity or the mixed criteria of these three. The performance of the model was measured and, then, compared with those of conventional ones in terns of average skidding distance, accessibility of stands, development index and circulated road network index. The results of the performance analysis indicate that selection of roading routes for network design using the digital terrain analysis and the area-partitioning method improves performance of the network design medel.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.26 no.3
• /
• pp.174-183
• /
• 2014

Seabed beneath and near coastal structures may undergo large excess pore water pressure composed of oscillatory and residual components in the case of long durations of high wave loading. This excess pore water pressure may reduce effective stress and, consequently, the seabed may liquefy. If liquefaction occurs in the seabed, the structure may sink, overturn, and eventually increase the failure potential. In this study, to evaluate the liquefaction potential on the seabed, numerical analysis was conducted using the expanded 2-dimensional numerical wave tank to account for an irregular wave field. In the condition of an irregular wave field, the dynamic wave pressure and water flow velocity acting on the seabed and the surface boundary of the composite breakwater structure were estimated. Simulation results were used as input data in a finite element computer program for elastoplastic seabed response. Simulations evaluated the time and spatial variations in excess pore water pressure, effective stress, and liquefaction potential in the seabed. Additionally, the deformation of the seabed and the displacement of the structure as a function of time were quantitatively evaluated. From the results of the analysis, the liquefaction potential at the seabed in front and rear of the composite breakwater was identified. Since the liquefied seabed particles have no resistance to force, scour potential could increase on the seabed. In addition, the strength decrease of the seabed due to the liquefaction can increase the structural motion and significantly influence the stability of the composite breakwater. Due to limitations of allowable paper length, the studied results were divided into two portions; (I) focusing on the dynamic response of structure, acceleration, deformation of seabed, and (II) focusing on the time variation in excess pore water pressure, liquefaction, effective stress path in the seabed. This paper corresponds to (II).

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.26 no.3
• /
• pp.160-173
• /
• 2014

Seabed beneath and near coastal structures may undergo large excess pore water pressure composed of oscillatory and residual components in the case of long durations of high wave loading. This excess pore water pressure may reduce effective stress and, consequently, the seabed may liquefy. If liquefaction occurs in the seabed, the structure may sink, overturn, and eventually increase the failure potential. In this study, to evaluate the liquefaction potential on the seabed, numerical analysis was conducted using the expanded 2-dimensional numerical wave tank to account for an irregular wave field. In the condition of an irregular wave field, the dynamic wave pressure and water flow velocity acting on the seabed and the surface boundary of the composite breakwater structure were estimated. Simulation results were used as input data in a finite element computer program for elastoplastic seabed response. Simulations evaluated the time and spatial variations in excess pore water pressure, effective stress, and liquefaction potential in the seabed. Additionally, the deformation of the seabed and the displacement of the structure as a function of time were quantitatively evaluated. From the results of the analysis, the liquefaction potential at the seabed in front and rear of the composite breakwater was identified. Since the liquefied seabed particles have no resistance to force, scour potential could increase on the seabed. In addition, the strength decrease of the seabed due to the liquefaction can increase the structural motion and significantly influence the stability of the composite breakwater. Due to limitations of allowable paper length, the studied results were divided into two portions; (I) focusing on the dynamic response of structure, acceleration, deformation of seabed, and (II) focusing on the time variation in excess pore water pressure, liquefaction, effective stress path in the seabed. This paper corresponds to (I).

• Korean Journal of Environment and Ecology
• /
• v.25 no.1
• /
• pp.1-9
• /
• 2011

In order to analyze the change in home ranges depending on the reproductive stage of Pipistrellus abramus, radio-tracking was carried out for a total of 9 individuals, 3 individuals each, by dividing stages into a pregnancy stage, lactation stage, and post-lactation stage from May to August 2009. For radio-telemetry, 0.38g transmitters, R2000 receivers and 3-element Yagi antennas were used. Pipistrellus abramus were captured using a double-stacked mist net and a harp-trap. Analysis of home ranges used a SHP File and ArcGIS 3.3 for GIS, and used a Kernel Home Range Method(KHR) and a Minimum Convex Polygon(MCP) Method for analysis. Home ranges at the pregnancy stage were MCP 100% $13.46{\pm}1.84ha$, MCP 95% $12.28{\pm}2.15ha$, KHR 50% $3.00{\pm}0.71ha$, and home ranges at the lactation stage were MCP 100% $8.13{\pm}0.23ha$, MCP 95% $7.73{\pm}0.63ha$, KHR 50%$1.84{\pm}1.05ha$. Home ranges at the post-lactation stage were MCP 100% $125.58{\pm}97.77ha$, MCP 95% $123.89{\pm}97.73ha$, KHR 50% $28.61{\pm}26.78ha$. As a result, home ranges of pipistrellus abramus showed a significant difference in all of the MCP 100%, MCP 95%, KHR 50% depending on reproductive stages, being largest in the post-lactation stage and smallest in the lactation stage.

• Journal of Nutrition and Health
• /
• v.51 no.4
• /
• pp.275-286
• /
• 2018

Purpose: Our previous study demonstrated that persimmon (Diospyros kaki Thumb.) at different stages of ripening provided different protective effects against high-fat/cholesterol diet (HFD)-induced dyslipidemia in rats. In this study, we compared the metabolites profile and gene expressions related to triglyceride (TG)/cholesterol metabolism in vitro and in vivo after treating with persimmon water extracts (PWE) or tannin-enriched persimmon concentrate (TEP). Methods: Primary and secondary metabolites in test materials were determined by GC-TOF/MS, UHPLC-LTQ-ESI-IT-MS/MS, and UPLC-Q-TOF-MS. The expression of genes related to TG and cholesterol metabolism were determined by RT-PCR both in HepG2 cells stimulated by oleic acid/palmitic acid and in liver tissues obtained from Wistar rats fed with HFD and PWE at 0, 150, 300, and 600 mg/d (experiment I) or TEP at 0, 7, 14, and 28 mg/d (experiment II) by oral gavage for 9 weeks. Results: PLS-DA analysis and heatmap analysis demonstrated significantly differential profiling of metabolites of PWE and TEP according to processing of persimmon powder. In vitro, TEP showed similar hypolipidemic effects as PWE, but significantly enhanced hypocholesterolemic effects compared to PWE in sterol regulatory element-binding protein 2 (SREBP2), HMG-CoA reductase (HMGCR), proprotein convertase subtilisin/kexin type 9 (PCSK9), cholesterol $7{\alpha}-hydroxylase$ (CYP7A1), and low density lipoprotein receptor (LDLR) gene expression. Consistently, TEP and PWE showed similar hypolipidemic capacity in vivo, but significantly enhanced hypocholesterolemic capacity in terms of SREBP2, HMGCR, and bile salt export pump (BSEP) gene expression. Conclusion: These results suggest that column extraction after hot water extraction may be a good strategy to enhance tannins and long-chain fatty acid amides, which might cause stimulation of hypocholesterolemic actions through downregulation of cholesterol biosynthesis gene expression and upregulation of LDL receptor gene expression.