• Journal of Korea Multimedia Society
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• v.12 no.11
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• pp.1692-1700
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• 2009

This paper proposes the direction distribution of surface normal vectors as a feature descriptor of three-dimensional models. Proposed the feature descriptor handles rotation invariance using a principal component analysis(PCA) method, and performs mesh simplification to make it robust and nonsensitive against noise addition. Our method picks samples for the distribution of normal vectors to be proportional to the area of each polygon, applies weight to the normal vectors, and applies interpolation to enhance discrimination so that the information on the surface with less area may be less reflected on composing a feature descriptor. This research measures similarity between models with a L1-norm in the probability density histogram where the distances of feature descriptors are normalized. Experimental results have shown that the proposed method has improved the retrieval performance described in an average normalized modified retrieval rank(ANMRR) by about 17.2% and the retrieval performance described in a quantitative discrimination scale by 9.6%~17.5% as compared to the existing method.

• Journal of Navigation and Port Research
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• v.28 no.6
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• pp.531-539
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• 2004

In this paper, we propose a new heuristic solution for 3D container packing problem for the variable sizes and types of freight. Frist of all, we consider the total cost of container charge i.e., handling, loading and transportation, where each freight will be specifically identified The types of containers and its number to be loaded am be selected automatically by minimizing the total cost of container charge. Maximization of loading space am be achieved efficiently by operating the palletizing and/or depalletizing of freight. By considering these factors we can determine the position of freight in the container and the loading sequence to be packing into the container. In container packing simulation, we can verify that the proposed heuristic algorithm indicates more efficiency space utilization and shows the possibility of using on commercial business.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.8
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• pp.631-638
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• 2018

In this paper, we propose a method to improve the performance by guidance technique and applying it to the precision guided ammunition. The proposed method is a technique designed to reduce the target error of ammunition by reducing the projectile error without analyzing the motion characteristics of the shot. This technique is applied to the moving average filter technique which is widely used as signal processing technique to reduce the fluctuation of the output of the inboard mounting inertial sensor caused by the rotation and the coning motion of the ammunition. In order to compare the performance of the applied technique including the simple 3D guided control technique and the proposed improvement technique. It is confirmed that the application of this technique improves the accuracy of impact of the cannon - launched ammunition with severe environmental conditions and irregular motion characteristics unlike the missile.

• Journal of Biomedical Engineering Research
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• v.31 no.1
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• pp.74-80
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• 2010

This paper presents the three dimensional gait analysis of the patients with osteoarticular knee allograft reconstruction. The gait analysis has been performed in some medical fields such as orthopedics and neurosurgery for the purpose of the rehabilitation of patients. However, to the author's knowledge, the analysis of gait for the patients with osteoarticular knee allograft reconstruction caused by tumor has not been reported. In this work, In this work, we confirmed the validity of this method by analyzing 50 samples per one gait cycle obtained from each of 3 patients and 3 normal persons. The motion capture was performed using six infrared cameras. The symmetry and stability of the gait patterns are investigated (patients' r=0.39, p<0.05, normal persons' r=0.65, p<0.05) respectively using the correlation coefficients and the standard deviations of the joint angles of the left and right legs. It also would be applied to the comparison analysis where artificial knee joint is transplanted.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.4 s.11
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• pp.145-151
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• 2003

The domestic and the industry wastes which mainly come out of human life activities have been usually processed mainly by the incineration method and/or the method of reclamation. The method of reclamation, specially open dumping, has caused significant environmental pollution problems on the local or regional soil and groundwater system by leachate. Therefore, to investigate the 3-D structure characteristics of environmental pollution area is one of the hot subjects. We applied dipole-dipole method of electrical resistivity survey to investigate 3-D environmental contamination characteristics of the Noeun landfill area. For electrical resistivity survey, the line for measurements was established parallel to the main boundary of the Noeun landfill, for effective investigation of the whole landfill area. The result shows that the uppermost layer of the Noeun landfill is believed to be stabilized completely, based on the result of electrical resistivity values. However, the lowest layer of the Noeun landfill was partially polluted by leachate. Therefore, the electrical resistivity survey method is believed to be the one of the most effective methods to investigate three-dimensional distribution of leachate occurred in the lower part of landfill area.

• Journal of Korean Society of Steel Construction
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• v.24 no.2
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• pp.175-188
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• 2012

A parametric study for varying the radii of curvature is performed with a curved tub girder bridge having three continuous spans. The bracing forces of top lateral bracings from the results of numerical equations are compared to those of 3-dimensional finite element analyses. New modifying factors applicable in computing the nominal member forces of top lateral bracings were suggested. The numerical equations were derived based on one girder system, and it is shown that the numerical equations exhibit some errors compared with 3D FEA results. The main reason for this phenomenon lies on the number of girders. The twin girder system has an external cross-beam between inner and outer girder. It also has larger lateral stiffness than the single girder system. Finally, the distributions by the torsion, bending, distortion, and lateral loading of the top lateral bracing forces were presented in this paper.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.4 s.38
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• pp.61-70
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• 2006

This paper presents photogrammetric processing to generate digital elevation models using SPOT-5 HRG stereo images and deals with the accuracy potential of HRG (High Resolution Geometry) supermode imagery for DEM generation. After bundle adjustment was preformed for sensor modelling, digital surface models were generated through the procedures of Epipolar image resampling and image matching. The DEM extracted from HRG imagery was compared along several test sections with the the refernce DEM which was obtained from the digital topographic maps of a scale of 1 to 5000. The ratio of the zone with DEM errors less than 5m to the whole zone was 53.8%, and about 2.5m RMSE was showed when assuming that the zones larger than 5m were affected by clouds, water bodies and buildings and excluding those zones from accuracy evaluation. In addition, the three-dimensional bird's eye view model and 3D building model were producted based on the DSM which was extracted from SPOT-5 HRG data.

• Journal of Electrochemical Science and Technology
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• v.9 no.3
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• pp.202-211
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• 2018

In this work, Fe-Pd alloy films have been electrodeposited on different substrates using an electrolyte containing $[Pd(NH_3)_4]^{2+}$ (0.02 M) and $[Fe-Citrate]^{2+}$ (0.2 M). The influences of substrate and overpotential on chemical composition, nucleation and growth kinetics as well as the electrodeposited films morphology have been investigated using energy dispersive X-ray spectroscopy (EDS), current-time transients, scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD) patterns. In all substrates - brass, copper and sputtered fluorine doped tin oxide on glass (FTO/glass) - Fe content of the electrodeposited alloys increases by increasing the overpotential. Also the cathodic current efficiency is low due to high rate of $H_2$ co-reduction. Regarding the chronoamperometry current-time transients, it has been demonstrated that the nucleation mechanism is instantaneous with a typical three dimensional (3D) diffusion-controlled growth in the case of brass and copper substrates; while for FTO, the growth mode changes to 3D progressive. At a constant overpotential, the calculated number of active nucleation sites for metallic substrates is much higher than that of FTO/glass; however by increasing the overpotential, the number of active nucleation sites increases. The SEM micrographs as well as the XRD patterns reveal the formation of Fe-Pd alloy thin films with nanostructure arrangement and ultra-fine grains.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.4
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• pp.97-104
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• 2012

Recent climate change has increased the occurrence of flood disaster. There are two approaches to prevent flooding damage. One is a structural method and the other is a non-structural method. The production and usage of a flood risk map are the example of non-structural way. The flood risk map displays several kinds of information to minimize casualties and property damage caused from flooding. In order to increase the usage of current flood risk maps and improve intuitive recognition of flood information, this paper produced flood risk maps based on geo-spatial information system using three dimensional virtual reality techniques and investigated the applicability of the maps. Because flood information is easily accessed through online, flood risk maps suggested in this paper are regarded as an efficient tool.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.2 s.6
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• pp.29-42
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• 1995

Route design in topographical plane map brings many problems in efficiency and requires much time and labor by hand Recently, the active studies of efficient route design method using 3-D terrain information are being developed according to increasing concentration on GSIS. In order to analyze terrain information for route design efficiently, this study presents objective and overall datum by applying SQL in construction and analysis of database and the possibility of three-dimensional terrain information analysis, This study generates 3-D base map on topographical map of scale 1:5,000 and acquires terrain information that have various thematic map data; contour, land use, roadway, and drange. This is a study on the application of SQL in route design and construction of the terrain information that linked by graphic datum of completed topographical map and attributed datum of database. As the result of this study, we can produce promptly and efficiently design datum of profile annotation, cross section, and volume computations to the preliminary route for route design and apply this efficient method to route design by understanding visual DTM which is composed of the roadway and the natural scene after design.