• The Journal of Engineering Geology
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• v.20 no.3
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• pp.281-295
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• 2010

A new, automated apparatus is proposed for calculating the Soil-Water Characteristic Curve (SWCC), representing a simple and easily applied testing device for continuous measurements of the volumetric water content and suction of unsaturated soils. The use of this apparatus helps to avoid the errors that arise when performing experiments. Consequently, the apparatus provides greater accuracy in calculating the SWCC of unsaturated soils. The apparatus is composed of a pressure panel, flow cell, water reservoir, air bubble trap, balance, sample-preparation accessories, and measurement system, among other components. The air pressure can attain 300 kPa, and a general test can be completed in a short time. The apparatus can simply control the drying process and wetting process. The changes in volumetric water content that occur during the drying and wetting processes are shown directly in the SWRC program, in real time. As a case study, we performed an SWCC test of Joomunjin sand (75% relative density) to measure matric suction and volumetric water content during both the drying and wetting processes. The test revealed hysteresis behavior, whereby the water content on the wetting curve is always lower than that on the drying curve for a specific matric suction, during the wetting and drying processes. Based on the test results, SWCCs were estimated using the Brooks and Corey, van Genuchten, and Fredlund and Xing models. The van Genuchten model performed best for the given soil conditions, as it yielded the highest coefficient of determination.

• Science of Emotion and Sensibility
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• v.14 no.3
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• pp.435-444
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• 2011

The development of ubiquitous healthcare technology and portable electronic devices requires new energy sources for providing continuous power supply. This study particularly focuses on an energy harvesting system capable of charging energy using clothing. One of the sources for energy harvesting is heat energy, which is the difference in temperature of the body and the surrounding environment. In this study, the skin temperature distribution of the human body was empirically measured to determine the basic materials needed to develop heat energy harvesting clothing. The distribution of skin temperature in different sections of the human body was analyzed. The analysis found that the skin temperature of the upper body was higher than that of the lower body. The area close to the heart with a lot of blood flow was especially high. The skin temperature of the back side of the body, such as the back of the neck, upper back, and waist, was higher than that of the front side of the body. As for the arms, the skin temperature of the upper arms was higher than that of the lower arms, and the skin temperature of the back side of the arms was lower than that of the front and the flank side of the arms. The difference in the average skin temperature and the environment temperature was highest at the back of the neck, and thereby is considered to be the most appropriate section to integrate the heat energy harvesting function and structure. The following sections had the next highest difference in values, listed in descending order: the back of the waist, the sides of shoulders, the front chest area, the front side of the upper arms, and the front abdomen. Based on the skin temperatures of the different sections of the human body, this study outlines the basic guidelines for developing heat energy harvesting clothing.

• Korean Institute of Interior Design Journal
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• v.22 no.4
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• pp.23-32
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• 2013

This study represents something in common and differences of organic characteristics between early modern architecture and contemporary architecture analysing F. L. Wright's Robie House and Toyo Ito's Sendai Mediatheque. A natural organic body cannot be separated from the natural environment, and each part of an architecture has each own property and forms a whole at the same time. That is a basic concept of organic architecture, and a framework for analysis is set up based on it. The followings are similarities and differences of organic concept and interpretation between Wright's Robie House and Ito's Sendai Mediatheque First, Wright' Robie house unites with the natural surrounding, using a physically close connection to the ground. In contract, Ito's Mediatheque shows characteristics of noncentural and fluidic space that are metaphorically reflecting tangible and intangible of factors in modern city, where there is an ambiguous physical boundary between architecture and urban environment. Next, floors, walls and ceilings of Wright's housing as for basic building blocks are physically separated and at the same time form formative unity from the point of view of a physical and structural organic body. And continuous flow of faces of separated walls form an organism united with the nature from a physical aspect. On the contrary to this, there is an no-boudary and floating organic architecture of integrated structure from ambiguous setting of relation between architecture and urban space in Ito's architecture. Especially, Mediatheque shows semantic integration of floating urban environmental factors through horizontal and vertical integration of horizontal slabs, vertical pipes, and skins. Last, horizontal and vertical factors of Wright' Housing is appreciated as an basic experienced structure in terms of spacial perception and fluidic inner spaces in Wright's housing is completed with a series of spatial experiences in a visual sense. On the other hand, no-boundary and floating space of Ito's architecture accept user's physical and virtual body. Especially, there is an integration transcending beyond time and space, accepting an imaginary body and events with the course of time at Ito's Mediatheque.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.29-37
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• 2020

In the past, meta-heuristic optimization algorithms were developed to solve the problems caused by complex nonlinearities occurring in natural phenomena, and various studies have been conducted to examine the applicability of the developed algorithms. The self-adaptive vision correction algorithm (SAVCA) showed excellent performance in mathematics problems, but it did not apply to complex engineering problems. Therefore, it is necessary to review the application process of the SAVCA. The SAVCA, which was recently developed and showed excellent performance, was applied to the advanced Muskingum flood routing model (ANLMM-L) to examine the application and application process. First, initial solutions were generated by the SAVCA, and the fitness was then calculated by ANLMM-L. The new value selected by a local and global search was put into the SAVCA. A new solution was generated, and ANLMM-L was applied again to calculate the fitness. The final calculation was conducted by comparing and improving the results of the new solution and existing solutions. The sum of squares (SSQ) was used to calculate the error between the observed and calculated runoff, and the applied results were compared with the current models. SAVCA, which showed excellent performance in the Muskingum flood routing model, is expected to show excellent performance in a range of engineering problems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.110-117
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• 2017

In the construction of high-rise residential buildings in which the finishing works are done repetitively in each housing unit, the construction period and cost can be reduced, while maintaining the quality, if the work process is properly managed in order for the resources to be input continuously. Time management methods such as the Bar Chart, CPM and LOB are not appropriate, due to the difficulties involved in the diagraming of repetitive works and applying them to the project. The Tact method also has difficulties in maintaining a constant work flow and needs significant effort and cooperation from the subcontractors to allocate the resources consistently. Partitioning, base works for finishing, floor mortar plastering and the final finishing work are done sequentially in residential buildings projects, and there are many repetitive activities which differ in terms of the work method, work area and productivity. If these repetitive activities are synchronized or converged toward the last work area, the goal of process management can be achieved effectively. Therefore, a process planning method for the finishing works of residential building projects is proposed, which takes into consideration elements, such as the sequential relation between the activities in each housing unit and classification of repetitive works in terms of their management method, work area and production rate, for the continuous input of resources into the housing units.

• Journal of Biomedical Engineering Research
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• v.38 no.2
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• pp.62-73
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• 2017

To identify a solution for the restricted availability of healthy lungs and the high risk of immune rejections following organ transplantation, tissue engineering techniques for culturing lungs have been studied by many research groups. The most promising method for culturing lungs is the utilization of a bio-scaffold that was prepared using harvested organs from human donors or other animals by removing their original cells. In this study, a pulsatile perfusion pump was used to alleviate the cell removal effect with the high fluid-dynamic power of the perfusion stream during the decellularization process, while other conventional studies focused on chemical methods to identify efficient detergents. The purpose of this study was to analyze the developed device by using energy equivalent pressure (EEP), which is an indicator of pulsatility, to understand the characteristics of pulsatile energy transmitted according to the load size by using the artificial model and compare it with the measured EEP. The pulsatility of the device can be estimated with the concept of fluid-dynamic energy during a particular constant time period or fluid-dynamic power represented as EEP and EEP increment. Because the measured EEP of perfusion flow during decellularization can be changed by the amount of fluid leakage and the degree of clogging in the capillary vessels, EEP should be measured to determine whether the decellularization is progressing without problems. The decrement of EEP caused by the high perfusion resistance was observed from some experimental results that were obtained with artificial models. EEP can be used to monitor the decellularization process after analyzing the varying EEP according to the amount of load. It was confirmed that the EEP was maintained at a high level in the experiment using the harvested lungs from 12-13-week-old rats. In addition, it was confirmed that the cell removal time was faster than when continuous perfusion was performed. In this study, pulsatile power delivered to the lungs was measured to monitor the process of cell removal, and it serve as the evidence for efficient decellularization.

• Journal of Korea Water Resources Association
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• v.42 no.10
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• pp.891-896
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• 2009

The puff models have been developed to simulate the advection-diffusion processes of dredging suspended solids, either alone or in combination with Eulerian models. Computational efficiency and accuracy are of prime importance in designing these hybrid approaches to simulate a pollutant discharge, and we characterize two relatively simple Lagrangian techniques in this regard: forward Gaussian puff tracking (FGPT), and backward Gaussian puff tracking (BGPT). FGPT and BGPT offer dramatic savings in computational expense, but their applicability is limited by accuracy concerns in the presence of spatially variable flow or diffusivity fields or complex no-flux or open boundary conditions. For long simulations, particle and/or puff methods can transition to an Eulerian model if appropriate, since the relative computational expense of Lagrangian methods increases with time for continuous sources. Although we focus on simple Lagrangian models that are not suitable to all environmental applications, many of the implementation and computational efficiency concerns outlined herein would also be relevant to using higher order particle and puff methods to extend the near field.

• The Journal of the Petrological Society of Korea
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• v.7 no.3
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• pp.161-176
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• 1998

There are exposed Samrangjin Tuff and intracaldera intrusions, of which rhyolitic rocks emplaced as postcollapsed central and ring intrusions within the Samrangjin caldera, and fine-grained granodiorite and biotite granite as regional tectonic intrusions nearby. The Samrangjin Tuff and the rhyolitic rocks are of a single Samrangjin magmatic system. Flow-banded rhyolite among rhyolitic rocks was emplaced in the outer part of the ring intrusions, rhyodacite in the inner part of the eastern ring, and porphyritic dacite and dacite porphyry in the inner part of the northwestern ring. Totally the Samrangjin Tuff and the rhyolitic rocks range from rhyolite to dacite in chemical composition. The Rb-Sr isotopic data of the Samrangjin Tuff and the rhyolitic rocks yield an age of $80.8{\pm}1.5(2{\sigma})$ Ma with the initial $^{87}Sr/^{86}Sr$ ratio of $0.70521{\pm}0.00010(2{\sigma})$. The continuous compositional zonations generally define a large stratified magma system in the postcollapse magma chamber. The Sr isotopic data suggest that the compositional zonations might have resulted from the fractional crystallization of a parental dacitic magma.

• Journal of Korea Water Resources Association
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• v.50 no.6
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• pp.407-418
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• 2017

Due to geographical features of being close to DPRK (Democratic People's Republic of Korea), the Imjin River basin has difficulties in hydrological observation, and is vulnerable to unexpected flood occurrence. As a countermeasure, Gunnam Flood Control Reservoir construction was planned in 2005. Despite such a structural measure, damages by DPRK's illegal release continues to occur. Futhermore the Imjin River's flow has been decreased due to the effect of continuous drought in the Korean Peninsula since 2012 and DPRK's unilateral storage of water. A new operation method is derived for the Gunnam Flood Control Reservoir in order to cope with drought damages on the Imjin River basin and to ensure efficient response time upon flooding. The operation method maintaining Gunnam Flood Control Reservoir's water level by raising from EL.23.0 m to EL.31.0 m during the flood season for securing reservoir capacity enables to secure additional $14,000,000m^3$ water compared to the existing operation methods. The operation method to store inflow by controlling release to $250m^3/s$ in the early stage of flood has increased 2.66% on average in terms of detention effect of reservoir compared to the existing operation methods. The method enables to secure 19 hours to prepare flood compared to the existing methods.

• Journal of Acupuncture Research
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• v.24 no.6
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• pp.45-61
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• 2007

Objectives : The purpose of this study is to observe the effects of Carthami Flos herbal-acupuncture (CF-HA) at Joksamni($ST_{36}$) on arthritis in mice induced by Collagen II. Methods : The author performed several experimental items, including arthritis evaluation, change in weight, spleen size and stenosis rate, change in cytokine level, IgG, IgM and anti-collagen II, change of immunocyte count and histological change of the CIA mouse joint. Conclusions are as follows: Results : 1. In the CF-HA, the arthritis index and rate and the incidence of arthritis were decreased as the experiment proceeded. 2. In the CF-HA, spleen swell and stenosis, joint edema and change were decreased. 3. In the CF-HA, the level of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$ and $IFN-{\gamma}$ in blood serum were significantly decreased. 4. In the CF-HA, the level of IgG, IgM and anti-collagen II were decreased. 5. In the CF- HA, $IFN-{\gamma}$, $IFN-{\gamma}/IL-4$, IL-10 of the culture fluid was decreased. 6. In the CF-HA, the cell rate of $CD3e^+$ and $CD45R^+$, $CD4^+$ and $CD8^+$, $CD4^+/CD25^+$ in spleen was similar to the cell rate of the normal group. 7. In the CF-HA, the cell rate of $CD4^+/CD25^+$, $CD45R^+/CD69^+$ in a lymph node was decreased as in the normal group. 8. In the CF-HA, the cell rate of $CD3^+/CD69^+$, $CD11b^+/Gr-1^+$ in joints was decreased as in the normal group. 9. In the CF-HA, the cartilage destruction and the inflammation cell growth in the H&E stain were decreased. The collagen fiber in the M&T stain were less destructed, therefore the result was similar to the normal group. Conclusions : These results suggest that CH-HA at $ST_{36}$ has an effect in controlling immune reaction and suppressing inflammation in rheumatoid arthritis therefore, the continuous flow of the following study is expected.