• Journal of the Korean Data and Information Science Society
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• v.15 no.1
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• pp.107-117
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• 2004

Change point testing problem is considered. Kernel density estimators are used for constructing proposed change point test statistics. The proposed method can be used to the hypothesis testing of not only parameter change but also distributional change. Bootstrap method is applied to get the sampling distribution of proposed test statistic. Small sample Monte Carlo Simulation were also conducted in order to show the performance of proposed method.

• Journal of Korean Society on Water Environment
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• v.24 no.3
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• pp.345-353
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• 2008

In order to design storage-based non-point source management facilities, the aspect of statistical features of the entire precipitation time series should be considered since non-point source pollutions are delivered by continuous rainfall runoffs. The 3-parameter mixed exponential probability density function instead of traditional single-parameter exponential probability density function is applied to represent the probabilistic features of long-term precipitation time series and model urban stormwater runoff. Finally, probability density functions of water quality control basin overflow are derived under two extreme intial conditions. The 31-year continuous precipitation time series recorded in Busan are analyzed to show that the 3-parameter mixed exponential probability density function gives better resolution.

• Journal of environmental and Sanitary engineering
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• v.21 no.2 s.60
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• pp.11-19
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• 2006

Ran numerical analysis about simplicity warm current model (simple turbulence model) to examine closely distributed laying stress on NOx of contaminant that happen in downtown that building is massed and result is as following. Downtown building is massed and transfer of vehicles can know that frequent area receives greatly effect of building. Pollution displays class kind phenomenon striking in the building, class kind done pollution that show high density being mixed with pollution that happen in vehicles being flowed in again side know can. Divide velocity vector of pollution and density change to ancient city and did numerical analysis. Because NOx is flowed in diversion of water neighborhood by continuous this kind in Godo 20m point, density showed density of $0.0907mg/m^3s$, and can know that Banryuhyeon that Pollution strikes in the building at ancient city 30m point is decreased and approaches with freedom flowing without cooperation (cavity) phenomenon remarkably. Because pollution strikes in the building at distance shaft 383m point, class kind do phenomenon that know appeared notedly Nopeungeonmulgwanat between building pollution density $0.067mg/m^3$ head of a families high appear.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.5
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• pp.127-134
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• 2007

Presented in the paper is an algorithm to generate a section curve by slicing a point cloud including tens of thousands of points. Although, there have been previous research results on the slicing problem, they are quite sensitive on the density variations of the point cloud, as well as on the local noise in the point cloud. To relive the difficulties, three technological requirements are identified; 1) dominant point sampling, 2) avoiding local vibration, and 3) robustness on the density changes. To satisfy these requirements, we propose a new slicing algorithm which is based on a node-sphere diagram. The algorithm has been implemented and tested with various examples.

• Earthquakes and Structures
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• v.15 no.2
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• pp.123-132
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• 2018

In this paper the strain energy density (SED) model is used to analyze the seismic behavior of suspen-domes and a new criterion is established for judging the seismic failure based on a characteristic point in the SED model. Firstly, a nonlinear time-history response analysis was carried out using the finite-element package ANSYS for typical suspen-domes subjected to different ground motions. The seismic responses including nodal displacements, ratios of yielding members, strain energy density and structural maximum deformation energy were extracted corresponding to the increasing peak ground acceleration (A). Secondly, the SED sum ($I_d$) was calculated which revealed that the $I_d-A$ curve exhibited a relatively large change (called a characteristic point) at a certain value of A with a very small load increment after the structures entered the elastic-plastic state. Thirdly, a SED criterion is proposed to judge the seismic failure load based on the characteristic point. Subsequently, the case study verifies the characteristic point and the proposed SED criterion. Finally, this paper describes the unity and application of the SED criterion. The SED method may open a new way for structural appraisal and the SED criterion might give a unified criterion for predicting the failure loads of various structures subjected to dynamic loads.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.6
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• pp.181-192
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• 2001

The power flow analysis (PFA) has been performed to analyze the vibration of coupled plates excited by a point force in an arbitrary direction. The point force generates the out-of-plane vibration associated wish flexural waves and the in-plane vibration associated with longitudinal and shear waves. The energy governing equation for each type of waves was introduced and solved to Predict the vibrational energy density and intensity generated by the out-of-plane and in-plane components of the point force in an arbitrary direction. The wave transmission approach was used to consider the mode conversion at the joint of the coupled plates. Numerical results for vibrational energy density and intensity on the coupled plates were presented. Comparison of the results by PFA with exact results showed that PFA can be an effective tool to predict the spatial variation of the vibrational energy and intensity on the coupled plates at high frequencies.

• Communications of the Korean Mathematical Society
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• v.20 no.4
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• pp.813-826
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• 2005

Regarding all particles at a fixed site as a cluster, the size of the largest cluster under the zero range invariant measures is well studied by Jeon et al.[5] for the case of density one. Here, the density of the finite zero-range process is given by the ratio between the number m of particles and the number n of sites. In this paper, we study the lower density case, i.e., the case m = o(n). Especially, when m ~ $n^{\beta}$,0 < ${\beta}$ < 1, we show that there is an interesting cutoff point around $\beta$ = 1/2.

• The Bulletin of The Korean Astronomical Society
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• v.30 no.2
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• pp.28.1-28.1
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• 2005

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1996.11a
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• pp.43-48
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• 1996

It is considered that automobile inner space is dangerous due to its combustion characteristics. (Automobile interior is largely made by plastic materials.) At last it is necessary to study on combustion characteristics of automobile interior. we could obtain its rapid combustion velocity and high smoke density by using ASTM D 2863 apparatus, DSC (Differential Scanning Calorimetry), Smoke density apparatus and so on. The study is summerized by following conditions and results. 1. Sample size was 150mm(length)$\times$60mmwidth). 2. Combustion velocity appeared peak point in the 2cm point. 3. PVC and foam layers are important factors in the face of smoke density. 4. Using DSC, we obtained the point that automobile interior was melted. 5. Automobile interior should be improved because of its low L.O.I value and rapid flame propagation velocity.

• International Journal of CAD/CAM
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• v.9 no.1
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• pp.31-36
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• 2010

3D point data acquired from laser scan or stereo vision can be quite noisy. A preprocessing step is often needed before a surface reconstruction algorithm can be applied. In this paper, we propose a nonparametric approach for noisy point data preprocessing. In particular, we proposed an anisotropic kernel based nonparametric density estimation method for outlier removal, and a hill-climbing line search approach for projecting data points onto the real surface boundary. Our approach is simple, robust and efficient. We demonstrate our method on both real and synthetic point datasets.