• International Journal of Control, Automation, and Systems
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• v.4 no.3
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• pp.325-332
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• 2006

The dynamic responses of human standing postural control were investigated when subjects were exposed to long-term horizontal vibration. It was hypothesized that the motion of standing posture complexity mainly occurs in the mid-sagittal plane. The motor-driven support platform was designed as a source of vibration. The AC Servo-controlled motors produced anterior/posterior (AP) motion. The platform acceleration and the trunk angular velocity were used as the input and the output of the system, respectively. A method was proposed to identify the complexity of the standing posture dynamics. That is, during AP platform motion, the subject's knee, hip and neck were tightly constrained by fixing assembly, so the lower extremity, trunk and head of the subject's body were individually immovable. Through this method, it was assumed that the ankle joint rotation mainly contributed to maintaining their body balance. Four subjects took part in this study. During the experiment, the random vibration was generated at a magnitude of $0.44m/s^2$, and the duration of each trial was 40 seconds. Measured data were estimated by the coherence function and the frequency response function for analyzing the dynamic behavior of standing control over a frequency range from 0.2 to 3 Hz. Significant coherence values were found above 0.5 Hz. The estimation of frequency response function revealed the dominant resonance frequencies between 0.60 Hz and 0.68 Hz. On the basis of our results illustrated here, the linear model of standing postural control was further concluded.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1666-1672
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• 2008

In this study, it collected and analyzed a construction case of the improved top-down support system application field on a case by case retaining wall method. The behavior of horizontal displacement was analyzed according to retaining wall type after reviewing a design stage and estimated horizontal displacement under the construction. The study results showed that it is judged stable until excavation termination irrelevant to a retaining wall method at the improved top-down support system application. It is judged that the settlement of behind ground can minimize because the retaining wall head displacement also behave stably. It was compared the predicted horizontal displacement in design and the measured horizontal displacement acquired through a measurement by using Elasto-Plastic analysis program. The comparison results showed that a similar horizontal displacement was predicted within stability standard irrelevant to a retaining wall method. So, it is decided that the advanced prediction is reasonable by Elasto-Plastic analysis in design applied the improved top-down support system. In the case of the ground anchor method application under a same condition, it is decided that a horizontal displacement will more increase than the improved top-down support system is applied. If a section condition is same, it was decided that to apply top-down support system is more stable than that.

• Journal of KIBIM
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• v.3 no.2
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• pp.19-27
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• 2013

The application of the BIM for the KEPCO' new headquarters in Naju involved alternative approaches and accompanied many trials-and-errors as the project adopted new targets and purposes that were not used in Korea before. In particular, for a large BIM-based project, clearly defining the BIM-including the objective, scope and the outcome-is critical for a project owner. For a successful implementation, project owners should improve the utilization of the BIM. Against this background, this research examines the case of the BIM application for the KEPCO' new headquarters in Naju, identifies its effects and problems, and proposes how to improve application of the BIM for public projects. The improvement in the BIM application can be divided into several stages: project order, design development, construction, and post-construction maintenance. In the initial stage, it is important to fully discuss the project planning among participants, and clarify the goal, scope, expected outcomes and role of the BIM. In the design stage, the level of detail (LOD) for the 3D model should be defined in consideration of information use in the stages of estimation and construction. In the construction stage, the scope of project that is managed based on the processing and use of the BIM data should be clearly given and understood. After construction is complete, measures should be sought to use the BIM for maintenance, and corresponding requirements and outcomes should be provided. The analysis is expected to provide basic data for successful implementation of BIM-based public projects, by assisting project owners and involved parties in enhancing work in different stages of a project.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.59-70
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• 2013

As people invest most of their asset in real estate, there is high interest in changing in housing and real estate prices in the future for a digital economy. Various variables are affecting the housing and real estate market. Among them, four variables : households, productive population, interest rate and index price are chosen and analyzed representatively. This study is aimed to build decision model of apartment prices in Seoul empirically. From the analysis result the stock index is the only variable which is significant statistically to apartments in Seoul. From this study, the households and productive population show the same direction as shown in the previous studies before but not significant statistically. Among the independent variables, the stock index is chosen as a major variable of determinant of Seoul apartment price. From the result of the research, prediction of stock market should be preceded to forecast the movement of housing and real estate market in the future.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.39 no.2
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• pp.69-78
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• 2002

This paper addresses a method to automatically detect out a person's face from a given image that consists of a hair and face view of the person and a complex background scene. Out method involves an effective detection algorithm that exploits the spatial distribution characteristics of human skin color via an adaptive fuzzy color classifier (AFCC), The universal skin-color map is derived on the chrominance component of human skin color in Cb, Cr and their corresponding luminance. The desired fuzzy system is applied to decide the skin color regions and those that are not. We use RGB model for extracting the hair color regions because the hair regions often show low brightness and chromaticity estimation of low brightness color is not stable. After some preprocessing, we apply convex-hull to each region. Consequent face detection is made from the relationship between a face's convex-hull and a head's convex-hull. The algorithm using the convex-hull shows better performance than the algorithm using pattern method. The performance of the proposed algorithm is shown by experiment. Experimental results show that the proposed algorithm successfully and efficiently detects the faces without constrained input conditions in color images.

• Journal of the Korean Chemical Society
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• v.20 no.2
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• pp.97-110
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• 1976

Effects of direct multiple quantum excitations in vibrational energy transfer were investigated. Vibrational transition probabilities for 0${\rightarrow}$2, 0${\rightarrow}$3, and 0${\rightarrow}$4 excitations were explicitly formulated including both direct 0→n excitations and stepwise single quantum processes. For the formulation the perturbing force was derived from the exponential potential including terms up to fourth order in the vibrational amplitude. The head-on collinear collision model between a harmonic oscillator and an incident particle was employed, and the formulation was based on the semiclassical approximation. Numerical results were obtained for five different collision systems (Ar${\cdots}$O-N, He${\cdots}$H-H, He${\cdots}$H-Cl, 5${\cdots}$1-2, 2${\cdots}$12-12). Comparison between the present results and those obtained using the linearized interaction potential showed that the overall effect of including the direct multiple quantum transition is to decrease the probabilities at low collision energies and to increase them at high energies. The present results were found to be significantly different from those obtained using the linearized potential for collision systems He${\cdots}$H-H, He${\cdots}$H-Cl, and 5${\cdots}$1-2. For systems Ar${\cdots}$O-N and 2${\cdots}$12-12 the differences were negligible.

• Journal of Ginseng Research
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• v.35 no.2
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• pp.138-148
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• 2011

Exponential rise in the use of mobile communication devices has generated health concerns due to radiofrequency (RF) exposure due to its close proximity to the head. Calcium binding proteins like calretinin regulate the levels of calcium ($Ca^{2+}$) which plays an important role in biological systems. Ginseng is known for maintaining equilibrium in the human body and may play a beneficial radioprotectant role against electromagnetic field (EMF) exposure. In the present study, we evaluated the radioprotective effects of red ginseng (RG) extract in a mouse model. Calretinin (CR) expression was measured using a free-floating immunohistochemical method in the hippocampus of mice after 835 MHz EMF exposure for 5 h/d for 5 d at specific absorption rate=1.6 W/kg for the different experimental groups. The control animals were treated with NaCl while the experimental animals received 10 mg/kg ginseng, or 30 mg/kg; EMF exposed mice were also treated with NaCl, 10 mg/kg ginseng (E10), or 30 mg/kg (E30). Decreases in CR immunoreactivity (IR) along with loss of CA1 and CA3 interneurons and infragranular cells were observed in the ENaCl group while such losses were not observed in the E10 and E30 groups. CR IR significantly increased in the RG-treated group compared to control and EMF-exposed groups treated with NaCl. The study demonstrates that RG extract can serve as a radioprotective agent that maintains $Ca^{2+}$ homeostasis and prevents neuronal loss in the brain hippocampal region caused by RF exposure.

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.121-129
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• 2011

One of the major challenges of minimum energy consumption for wireless sensor networks(WSN) environment. LEACH protocol is hierarchical routing protocol that obtains energy efficiency by using clustering. However, LEACH protocol in each round, because the new cluster configuration, cluster configuration, whenever the energy consumed shorten the life of the network. Therefore in this paper, the cluster is formed in WSN environment in early stage and the problems with energy waste have been solved by selecting C-node. In the initial round of proposed model uses 26 percent more than traditional LEACH energy consumption. However, as the round is ongoing, it has been proved by the network simulation tool that the waste of energy could be diminished up to 35%.

• Journal of the Korean Geotechnical Society
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• v.28 no.12
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• pp.99-110
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• 2012

Inclined Earth Retaining Structure Method (IER method, briefly) is developed in order to improve the existing earth retaining method. In IER method, there are three main structures, front support, back support, and head binding. Especially, back support acts the role that reduces the earth pressure acting on the front support. In this study, the stability according to the installation angle and stiffness of front or back support is analysed by model tests. By the test results, it is known that inclined back support is very effective to reduce the earth pressure acting on the front support. Especially, the effect of the stiffness and installation angle of back support is analysed.

• International Journal of Fluid Machinery and Systems
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• v.6 no.4
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• pp.200-205
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• 2013

In order to investigate the characteristics of unsteady flow in a mixed flow pump guide vane under the small flow conditions, several indicator points in a mixed flow pump guide vane was set, the three-dimensional unsteady turbulence numerical value of the mixed flow pump which is in the whole flow field will be calculated by means of the large eddy simulation (LES), sub-grid scale model and sliding mesh technology. The experimental results suggest that the large eddy simulation can estimate the positive slope characteristic of head & capacity curve. And the calculation results show that the pressure fluctuation coefficients of the middle section in guide vane inlet will decrease firstly and then increase. In guide vane outlet, the pressure fluctuation coefficients of section will be approximately axially symmetrical distribution. The pressure fluctuation minimum of section in guide vane inlet is above the middle location of the guide vane suction surface, and the pressure fluctuation minimum of section in which located the middle and outlet of guide vane. When it is under the small flow operating condition, the eddy scale of guide vane is larger, and the pressure fluctuation of the channel in guide vane being cyclical fluctuations obviously which leads to the area of eddy expanding to the whole channel from the suction side. The middle of the guide vane suction surface of the minimum amplitude pressure fluctuation to which the vortex core of eddy scale whose direction of fluid's rotation is the same to impeller in the guide vane adhere.