• Communications for Statistical Applications and Methods
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• v.25 no.5
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• pp.489-499
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• 2018

Jeonse is a unique property rental system in Korea in which a tenant pays a part of the price of a leased property as a fixed amount security deposit and gets back the entire deposit when the tenant moves out at the end of the tenancy. Jeonse deposit is very important in the Korean real estate market since it is directly related to the residential property sales price and it is a key indicator to predict future real estate market trend. Jeonse deposit data shows a skewed and heteroscedastic distribution and the commonly used mean regression model may be inappropriate for the analysis of Jeonse deposit data. In this paper, we apply a Bayesian quantile regression model to analyze Jeonse deposit data, which is non-parametric and does not require any distributional assumptions. Analysis results show that the quantile regression coefficients of most explanatory variables change dramatically for different quantiles. The regression coefficients of some variables have different signs for different quantiles, implying that even the same variable may affect the Jeonse deposit in the opposite direction depending on the amount of deposit.

• Journal of the Society of Naval Architects of Korea
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• v.33 no.4
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• pp.87-96
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• 1996

The dynamic ice forces on a structure with vertical wall and the corresponding responses of the structure are predicted. The structure was simplified as a 1-degree-of freedom system which consists of spring-mass-damper. Ice was divided into two parts : near filed and far field. In the near field, ice sheet moves with constant speed. The results obtained from the numerical simulation using the model and the experiment of indentation with stiff and flexible structures are compared. The comparisons show that the model can predict the behavior of structure and ice load with accuracy.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.4
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• pp.345-352
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• 2008

The motion of a projectile initiated by the release of highly pressurized air is simulated presuming the flow field as a two dimensional one. The effects of water compressibility on projectile movements are investigated, comparing results based on the Fluent VOF model where water is treated as an incompressible medium with those from the presently developed VOF scheme. The present model considers compressibility of both air and water. The Fluent results show that the body moves farther and at higher speeds than the present ones. As time proceeds, the relative difference of speed and displacement between the two results drops substantially, after acoustic waves in water traverse and return the full length of the tube several times. To estimate instantaneous accelerations, however, requires implementation of the water compressibility effect as discrepancies between them do not decrease even after several pressure wave cycles.

• The KIPS Transactions:PartA
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• v.10A no.1
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• pp.35-42
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• 2003

In this paper, we analyzed the known agent tracking models and proposed a new agent tracking model based on the distributed event service that always assures reliable tracking. Also we experimented the Performance of the event servers on the agent monitoring system that implements the distributed event service and showed their performance to decrement gracefully. The proposed tracking model doesn't make only several clients trace a mobile agent which moves among agent servers autonomously, but also supports two types of agent tracking agent location tracking that notifies agent location to the clients and path establishment that maintains reliable connection between agent servers for message delivery.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.10
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• pp.1029-1036
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• 2011

An energy-efficient reference walking trajectory generation algorithm is suggested utilizing allowable ZMP (Zero-Moment-Point) region, which maxmizes the energy efficiency for cyclic gaits, based on three-dimensional LIPM (Linear Inverted Pendulum Model) for biped robots. As observed in natural human walking, variable ZMP manipulation is suggested, in which ZMP moves within the allowable region to reduce the joint stress (i.e., rapid acceleration and deceleration of body), and hence to reduce the consumed energy. In addition, opimization of footstep planning is conducted to decide the optimal step-length and body height for a given forward mean velocity to minimize a suitable energy performance - amount of energy required to carry a unit weight a unit distance. In this planning, in order to ensure physically realizable walking trajectory, we also considered geometrical constraints, ZMP stability condition, friction constraint, and yawing moment constraint. Simulations are performed with a 12-DOF 3D biped robot model to verify the effectiveness of the proposed method.

• Journal of the Korea Computer Graphics Society
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• v.9 no.2
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• pp.11-18
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• 2003

For extracting geometric features in 3D meshes according to user-steering with effective interactions. this paper generalizes the 2D algorithms of snapping and wrapping that. respectively. moves a cursor to a nearby feature and constructs feature boundaries. First. we define approximate curvatures and move cost functions that are the numerical values measuring the geometric characteristics of the meshes, By exploiting the measuring values. the algorithms of geometric snapping and geometric wrapping are developed and implemented. We also visualize the results from applying the algorithms to extracting geometric features of general 3D mesh models such as a face model and a tooth model.

• Journal of Ocean Engineering and Technology
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• v.20 no.4 s.71
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• pp.43-49
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• 2006

Detailed investigations were carried out on the stability of the dredged soil bed against wave actions, aimedat establishing the design method of artificial tidal flats using dredged soil. The soil was dredged at Nagoya port, Japan, and has a mean grain size of 0.013mm. Basic features of artificial dredged soil bed against wave actions were explained from a series of model experiments in a wave flume. The two types of section shapes were employed; one is a horizontal bed and the other is a sloped one. Changes of the bed profile, shear strength, grain size distribution and water content, according to the wave actions, were measured in detail. The cumulative effect of the wave actions, over about one week, was investigated. A dredged soil bed moves withthe wave actions with relatively small wave height. It should be especially. noted that the clay component is dissolved and flown out, away from the surface layer, and consequently the surface layer hardens, as if it is covered with sand. Wren the wave height is gradually increased, the bed is not liquefied and the shear strength of the dredged bed is increased by a wave-induced dissipation of pore pressures in the bed and a decrease of clay component by the wave-induced leakage.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2310-2312
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• 2003

This paper describes a navigation system for an autonomous vehicle in outdoor environments. The vehicle uses vision system to detect coordinates and DGPS information to determine the vehicles initial position and orientation. The vision system detects coordinates in the environment by referring to an environment model. As the vehicle moves, it estimates its position by conventional DGPS data, and matches up the coordinates with the environment model in order to reduce the error in the vehicles position estimate. The vehicles initial position and orientation are calculated from the coordinate values of the first and second locations, which are acquired by DGPS. Subsequent orientations and positions are derived. Experimental results in real environments have showed the effectiveness of our proposed navigation methods and real-time methods.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.99-110
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• 2021

This study aims to examine empirically the industry and economic fundamental factors that affect the stock prices of the leading palm oil company in Indonesia. The dynamics of stock price are analyzed using the autoregressive distribution lag (ARDL) model both for symmetric and asymmetric effects. The data used in this study are monthly data for the period from 2008:01 to 2020:03. In the long run, the company stock price moves in line with the competitor company stock price at the current time. The palm oil price has a positive effect on the stock price. Meanwhile, inflation negatively affects the stock price in the short run. The estimated equilibrium correction coefficient indicates a reasonably quick correction of the distortion of the stock price equilibrium in monthly dynamics. However, fundamental factors have asymmetric effects, especially the response of stock price when these factors decrease rather than increase in the short run. Stock prices that are responsive to declines in fundamental performance should be of particular concern to both investors and management in their strategic decision making. The results of this study will contribute to the enrichment of literature related to stock prices from the viewpoint of economic analysis on firm-level data.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.849-859
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• 2022

Feed-water valves (FWVs) are used to regulate the flow rate of water entering steam generators, which are very important devices in nuclear power plants. Due to the working environment of relatively high pressure and temperature, there is strength failure problem of valve body in some cases. Based on the thermo-fluid-solid coupling model, the valve body stress of the feed-water valve in the opening process is investigated. The flow field characteristics inside the valve and temperature change of the valve body with time are studied. The stress analysis of the valve body is carried out considering mechanical stress and thermal stress comprehensively. The results show that the area with relatively high-velocity area moves gradually from the bottom of the cross section to the top of the cross section with the increase of the opening degree. The whole valve body reaches the same temperature of 250 ℃ at the time of 1894 s. The maximum stress of the valve body meets the design requirements by stress assessment. This work can be referred for the design of FWVs and other similar valves.