• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.150-150
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• 2000

We as modal parameter estimation technique by developing a residual based system reconstruction and using the system matrix coordinate transformation. The modal parameters can be estimated from and residues of the system transfer functions expressed in modal coordinate basis, derived from the state space system matrices. However, for modal parameter estimation of multivariable and order structural systems over broad frequency bands, this non-iterative algorithm gives high accuracy in the natural fre- and damping ratios. From vibration tests on cross-ply and angle-ply composite laminates, the natural frequencies and damping ratios on be estimated using tile coordinates of the structural system reconstructed fro the experimental frequency response. These results are compared with those of finite element analysis and single-degree-of-freedom curve-fitting.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.527-527
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• 2000

Wean modal parameter estiimation technique by developing a residual based system reconstruction and using the system matrix coordinate transformation. The modal parameters can be estimated from and residues of the system transfer functions expressed in modal coordinate basis, derived from the state space system matrices. However, for modal parameter estimation of mllltivariable and order structural systems over broad frequency bands, this non-iterative algorithm gives high accuracy in the natural fre and damping ratios. From vibration tests on cross-ply and angle-ply composite laminates, the natural frequencies and damping ratios can be estimated using the coordinates of the structural system reconstructed from the experimental frequency response. These results are compared with those of finite element analysis and single-degree-of-freedom curve-fitting..

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.10a
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• pp.249-257
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• 1998

Vibration-resistant rubbers, whose elastic and shear behaviors are similar to viscoelastic materials, are used to make bracing dampers to reduce the building vibration. Experimental study is carried out to find the vibration characteristics of the dampers installed in the building model. The natural frequencies and modal damping ratios are obtained from the free vibration test and Fourier analysis. Shaking table test is performed to find the response behavior of the building model under earthquake loading. The present experimental study shows that the bracing dampers have the behavior of viscoelastic dampers, which increase the modal damping ratios and viscoelastic characteristics.

• Wind and Structures
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• v.12 no.3
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• pp.259-279
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• 2009

The paper is concerned with the numerical study of the cross-wind response of the 295 m-tall six-flue industrial chimney, located in the power station of Belchatow, Poland. The response of the chimney due to turbulent wind flow is caused by the lateral turbulence component and vortex excitation with taking into account motion-induced wind forces. The cross-wind response has been estimated by means of the random vibration approach. Three power spectral density functions suggested by Kaimal, Tieleman and Solari for the evaluation of the lateral turbulence component response are taken into account. The vortex excitation response has been calculated by means of the Vickery and Basu's model including some complements. Motion-induced wind forces acting on a vibrating chimney have been modeled as a nonlinear aerodynamic damping force. The influence of three components mentioned above on the total cross-wind response of the chimney has been investigated. Moreover, the influence of damping ratios, evaluated by Multi-mode Random Decrement Technique, and number of mode shapes of the chimney have been examined. Computer programmes have been developed to obtain responses of the chimney. The numerical results and their comparison are presented.

• Journal of the Society of Disaster Information
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• v.3 no.1
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• pp.69-86
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• 2007

The fire department has one of the most important role as public resources of response to disasters in the aspect of supply and the adequate distribution of resources of response is essential, but the distribution of the response capability to disaster of fire department does not reflect the regional hazard vulnerability and hazard risks. Researchers performed database process with simple mapping based on the regional fire disaster response capability and the regional hazard vulnerability and hazard risks. The cities and towns are divided to four types each, total eight types and relative threat ratios are extracted from every type. The fire disaster response capability was extracted from number of firemen and fire vehicles in defined region. The distribution of the fire disaster response capability was inadequate and not matching to relative threat especially in small cities and some types of towns. The regional relative threat and resources should be analyzed by more delicate mapping and software development in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.249-250
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• 1989

• Journal of the Korean Society of Safety
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• v.30 no.1
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• pp.8-13
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• 2015

The experimental design methodology was applied in the drop tube furnace (DTF) to predict the various combustion properties according to the operating conditions and to assess the coal plant safety. Response surface method (RSM) was introduced as a design of experiment, and the database for RSM was set with the numerical simulation of DTF. The dependent variables such as burnout ratios (BOR) of coal and $CO/CO_2$ ratios were mathematically described as a function of three independent variables (coal particle size, carrier gas flow rate, wall temperature) being modeled by the use of the central composite design (CCD), and evaluated using a second-order polynomial multiple regression model. The prediction of BOR showed a high coefficient of determination (R2) value, thus ensuring a satisfactory adjustment of the second-order polynomial multiple regression model with the simulation data. However, $CO/CO_2$ ratio had a big difference between calculated values and predicted values using conventional RSM, which might be mainly due to the dependent variable increses or decrease very steeply, and hence the second order polynomial cannot follow the rates. To relax the increasing rate of dependent variable, $CO/CO_2$ ratio was taken as common logarithms and worked again with RSM. The application of logarithms in the transformation of dependent variables showed that the accuracy was highly enhanced and predicted the simulation data well.

• International Journal of Ocean System Engineering
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• v.3 no.4
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• pp.175-187
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• 2013

Moonpools are vertical wells in a floating body used onboard many types of vessels like Exploration and drilling vessels, Production barges, Cable-laying vessels, Rock dumping vessels, Research and offshore support vessels. Moonpool gives passage to underwater activities for different types of ships as per their mission requirements. It is observed that inside a moonpool considerable relative motions may occur, depending on shape, depth of the moonpool and on the frequency range of the waves to which the ship is exposed. The vessel responses are entirely different in zero and non-zero Froude number. Former situation is paid attention in this study as the mission requirement of the platform is to be in the particular location for long period of operation. It is well known that there are two modes of responses depending on the shape of the moonpool viz., piston mode for square shape and sloshing mode for rectangular shapes with different aspect ratios of opening like 1:1.5 and 1:2 ratios. Circular shaped moonpool is also tested for measuring the responses. The vessel moored using heavy lines are modelled and tested in the wave basin. The pretensions of the lines are varied by altering the touchdown points and the dynamic tensions on the lines are measured. The different modes of oscillations of water column are measured using wave gauge and the vessel response at a particular situation is determined. RAOs calculated for various situations provide better insight to the designer.

• Korean Journal of Organic Agriculture
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• v.5 no.2
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• pp.93-104
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• 1997

In order to investigate the growth response of grasses to chitosan solution amended soil were studied from the standpoint of estimating the growth stimulating adequate concentrations of chitosan solution amended soil in each grass. Three species in this experiment used were orchardgrass, tall fescue and reed canarygrass. Six different concentrations of chitosan solution amended soil were 0%(control), 0.01%, 0.05%, 0.1%, 0.5% and 1.0%, respectively. The resulte obtained were as follows ; 1. Leaf area(LA), dry weight of leaf(LW), dry weight of shoot(SHW), biological yield(BY), C/f ratio and T/R ratio were significantly different between species. 2. Growth stimulating effect by chitosan solution amended soil were found in plant length(PL) and T/R ratios of grasses. 3. Adequate concentrations of chitosan solution amended soil were different between species. The highest values of yield components and dry weight of plant parts were obtained at 0.01% in orchardgrass, 0,05% in reed canarygrass and 1.0% in tall fescue, respectively. 4. The growth response of grasses to chitosan solution amended soil were different between species. Thus, an increase in leaf area(LA) and dry weight of leaf(LW) by chitosan solution amended soil was mainly contributed to increase in dry weight of shoot(SHW) and biological yield(BY) in orchardgrass. Chitosan solution amended soil also stimulated growth of shoot and increased in biological yield(BY) in tall fescue. In reed canarygrass contributed to increase in C/F ratios. 5. Adequate concentrations of chitosan solution amended soil for an economical benefit of cultivation and dry matter production of grasses were ranged from 0.01% to 0.05% levels.

• Journal of the Korean Dietetic Association
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• v.12 no.1
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• pp.32-43
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• 2006

The purpose of this study is to find out the optimal mixing ratios of three different amounts of pectin, sugar and citric acid for preparation of garlic jam through response surface methodology(RSM) based on the sweetness, pH, color, sensory and texture test. As the sucrose content increased, the sweetness, cohesiveness, color, flavor, gloss and overall palatability of garlic jam tended to be high and the lightness tended to be low. As the pectin content increased, the adhesiveness of garlic jam tended to increase. As the citric acid content increased, the overall palatability of garlic jam tended to be high and the pH tended to be low. The Pectin levels were included 1.8-2.1g, sucrose levels were included 325-342g and citric acid levels were 5.8-6.1g. The optimal mixing ratios of a pectin, sugar and citric acid for manufacturing the best quality of garlic jam were 2.0g, 334g and 6.0g, respectively.