• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.78-84
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• 2002

In VE(Value Engineering) process, function analysis technique is utilized as a stepping stone to induce creative idea. However, function analysis is regarded as the most difficult job for VE team to undertake. For this reason, the function analysis is not properly applied or even omitted in construction VE studies. The current problems of function analysis in construction VE are following: 1) lack of basic understanding of the function analysis as problem solving technique, 2) the sequential step-by-step analysis process, 3) lack of interrelationship between function analysis and other phase in th VE process, 4) lack of time, experience, training, and quantitative data etc. The existing function analysis is faultiness theoretically. However, it is not enough for efficient use in practice, Thus The study aims to suggest an function analysis application method and to develop a computerized FAST(function Analysis System Technique) diagramming model, called Easy-FAST, for the efficient and effective function analysis on construction VE projects.

• The KIPS Transactions:PartB
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• v.9B no.3
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• pp.293-302
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• 2002

Gradual scene change detection is known as more difficult problem then abrupt scene change detection on video data analysis for contents based retrieval. In this paper, we present a new method for scene change detection far both abrupt and gradual change using the variable dynamic threshold arid cut frame difference (CFD). For this, We present the characteristics arid mathematical models of gradual transitions anti then, how can be detected by the CFD. And also we present new scene change detection algorithm based on cut frame difference. By the experimental result using real world video data indicate that the proposed method detect various scene changes both abrupt and gradual change efficiently without time-consuming computation and any dependency on a kind of gradual change effects.

• The Journal of the Acoustical Society of Korea
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• v.21 no.1
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• pp.19-26
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• 2002

This paper defines the visual basic speech units, visemes and investigates various visual features of a lip for the effective Korean lipreading. First, we analyzed the visual characteristics of the Korean vowels from the database of the lip image sequences obtained from the multi-speakers, thereby giving a definition of seven Korean vowel visemes. Various spatio-temporal features of a lip are extracted from the feature points located on both inner and outer lip contours of image sequences and their classification performances are evaluated by using a hidden Markov model based classifier for effective lipreading. The experimental results for recognizing the Korean visemes have demonstrated that the feature victor containing the information of inner and outer lip contours can be effectively applied to lipreading and also the direction and magnitude of the movement of a lip feature point over time is quite useful for Korean lipreading.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.2
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• pp.10-15
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• 2014

For hypersonic aircraft, increase of flight speeds causes heat loads that are from aerodynamic heat and engine heat. The heat loads could lead structural change of aircraft's component and malfunctioning. Endothermic fuels are liquid hydrocarbon fuels which are able to absorb the heat loads by undergoing endothermic reactions, such as thermal and catalytic cracking. In this study, methylcyclohexane was selected as a model endothermic fuel and experiments on endothermic properties were implemented. To improve heat of endothermic reaction, we applied zeolites and confirmed that HZSM-5 was the best catalyst for the catalytic performance. The objective is to investigate catalytic effects for heat sink improvement. The catalyst could be applied to system that use kerosene fuel as endothermic fuel.

• Nuclear Engineering and Technology
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• v.24 no.1
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• pp.40-51
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• 1992

One of the important irradiation performance characteristics of the silicide dispersion fuel element in research reactors is the diameteral increase resulting from fuel swelling. This paper, will attempt to develop a physical model for the fuel swelling, DFSWELL, by analyzing the basic irradiation behaviours and some experimental evidences. From the experimental evidences, it was shown that the volume changes in irradiated U$_3$Si-Al were strongly dependent on temperature and fission rate. The quantitative-amount of swelling for silicide fuel is estimated by considering temperature, fission rate, solid fission product build-up and gas bubble behavior. The swelling for the silicide fuel is comprised of three major components : i ) a volume change due to the formation of an interfacial layer between the fuel particle and matrix. ii ) a volume change due to the accumulation of gas bubble nucleation iii ) a volume change due to the accumulation of solid fission products The DFSWELL model which takes into account the above three major physical components predicts well the absolute magnitude of silicide fuel swelling in accordance with the power histories in comparison with the experimental data.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.75-92
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• 1999

In this paper, the seismic analysis model for seismically isolated KALIMER reactor structures is developed and the modal analysis and the seismic time history analysis are carried out for seismic isolation and non-isolation cases. To check the seismic stress limit according to the ASME Code, the equivalent seismic stress analyses are preformed using the 3-D finite element model. From the seismic stress analysis, the seismic margins are calculated for structural members. The limit of seismic load is defined to show that the maximum input acceleration ensures the structural safety for seismic load. In comparison of seismic responses between seismic isolation and non-isolation cases, the seismic isolation design gives significantly reduced acceleration responses and relative displacements between structures. The seismic margin of KALIMER reactor structure is high enough to produce the limit seismic load 0.8g.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.2
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• pp.45-55
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• 1998

Although a number of methods have been proposed to predict the liquefaction potential, few methods have been developed by using the characteristic of material's microstructure. In this research, fundamental procedure is proposed for the assessment of liquefaction potential in saturated soils based on the Disturbed Sate Concept(DSC) model which can provide a unified constitutive model for the characterization of entire stress-strain behavior under cyclic loading. From this concept, the value of disturbance at threshold state (Critical Disturbance, $D_C$) in the deforming microstructure provides the basis for initial liquefaction. This method is verified with respect to data from Cyclic Truly Triaxial test for saturated Ottawa sand. Also, the relationship between liquefaction and initial confinig stress is defined using definition of $D_C$. It is believed that the new procedure for identifying liquefaction based on the DSC model can capture the behavior of liquefation, and as a result, it is shown to be on improvement over the available empirical procedures.

• KSBB Journal
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• v.11 no.4
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• pp.481-488
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• 1996

In spite of diverse applications of chitin derivatives, commercial use of chitin has been limited due to highly resistance to chemicals and the absense of proper solvents. One of methods to reduce such high resistance to chemicals is to make microcrystalline chitin(MCC) by hydrolysis of chitin. Presently, MCC is produced mainly by using high concentration of acid, but this treatment requires an extensive posttreatment to remove or recover acid. An alternative process for MCC production was developed by using dilute hydrochloric acid with ultrasound and hydrogen peroxide. The major parameters for this process were found to be acid concentration, swelling time and temperature, and irradiation time and frequency of ultrasound. The effects of these parameters on MCC molecular weight were investigated. The molecular weight of MCC produced at a typical condition was around 30,000 which was approximately 1/8 of that of chitin and approached to a constant value. This phenomenon was explained by introducing the model of molecular arrangement of cellulose. SEM analysis showed that both chitin and MCC had a fibrous shaped morphology and the fibril size of MCC was much smaller than that of chitin.

• Journal of Broadcast Engineering
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• v.13 no.6
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• pp.962-965
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• 2008

2-D shape descriptors, which are vectors representing characteristics of shapes, enable comparison and classification of shapes and are mainly applied to image and 3-D model retrieval. Existing descriptors have limitations that they only describe shapes of single closed contours or lack in precision, making it difficult to be applied to shapes with multiple contours. Therefore, in this paper, we propose a new shape descriptor called Multi-Curvature-Scale Space that can be applied to shapes with multiple contours. Specifically, we represent the topology of the sub-contours in the multi-contour along with Curvature-Scale Space descriptors to represent the shapes of each sub-contours. Also, by allowing the weight of each component to be controlled when computing the distance between descriptors the weight, we deal with ambiguities in measuring similarity between shapes. Results of various experiments that prove the effectiveness of proposed descriptor are presented.

• Tunnel and Underground Space
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• v.17 no.5
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• pp.360-371
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• 2007

This paper presents an application of drainage control and slope stability by GIS-based hydrological modeling to control the surface water from an operational point of view. This study was carried out on a region of Pasir open-pit coal mine, Indonesia. A detailed topographical survey was performed at the study area to generate a reliable DEM (Digital Elevation Model). Hydrology tools implemented in ArcGIS 9.1 were used to extract the characteristics of drainage system such as flow direction, flow accumulation and catchment area from DEM. The results of hydrological modeling and spatial analysis showed that current arrangement of pumping facility is not suitable and some vulnerable places to erosion exist on the bench face due to concentrated surface runoff. Finally, some practical measures were suggested to optimize the design of drainage system and to monitor the slope stability by the surface water management at the study region during heavy rainfall.