• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.1
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• pp.58-66
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• 1997

In order to evaluate the exact effect of detergency it is necessary both to measure the actual soil content by chemical analysis and to determine the degree of soil removal visually. Since it takes considerable time and effort to use both methods, usually one of the two methods is used. Many studies have been carried out through increasing the visibility of oily soil to evaluate detergency by measuring reflectance of fabrics. In this study Sudan Black B, an oil soluble dye was used as an indicator to increase the visibility of oily soil on cotton and polyester fabrics. The condition of artificially soiled fabrics and the method of evaluating detergency were investigated which represent the actual detergency of oily soil by measuring the reflectance only. Also the detergency of Sudan Black B and that of oily soil were compared with each other under various washing conditions, As a result, the K/S values converted from the reflectances showed a good correlation with the actual soil content. Linear relationship between K/S value and the actual soil content was obtained. The K/S values of washed fabrics were higher than those of unwashed fabrics which included same content of soil since the soil visibility changed during washing. But the difference was small when Sudan Black B was used. With the increase of soil content, detergency of cotton fabric decreased, but detergency of polyester fabric increased gradually. With regards to soiled fabrics, detergency of cotton fabric measured by K/S value was close to that of actual oily soil when Sudan black B was used as an indicator.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.8
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• pp.742-747
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• 2012

A modified NDIF method using a sub-domain approach is introduced to extract highly accurate eigenvalues of two-dimensional, arbitrarily shaped acoustic cavities. The NDIF method, which was developed by the authors for the eigen-mode analysis of arbitrarily shaped acoustic cavities, has the feature that it yields highly accurate eigenvalues compared with other analytical methods or numerical methods(FEM and BEM). However, the NDIF method has the weak point that it can be applicable for only convex cavities. It was revealed that the solution of the NDIF method is very inaccurate or is not suitable for concave cavities. To overcome the weak point, the paper proposes the sub-domain method of dividing a concave domain into several convex domains. Finally, the validity of the proposed method is verified in two case studies, which indicate that eigenvalues obtained by the proposed method are more accurate compared to the exact method, the NDIF method, or FEM(ANSYS).

• 보존과학연구
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• s.26
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• pp.57-75
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• 2005

The burial custom in the Youngsan river area was to build a jar-coffin and lay the body in state, however the methods in building and moulding the massive jar, as well as in which kiln it was made has not been examined precisely. Thus, this research not only investigates previous results related to the manufacturing methods of massive jar-coffins, but also examines samples that were excavated and collected. The clay used to produce jar-coffin consists a large portion of unglazed qualities, which was split-moulded from the bottom up to the mouth area. The interior was finished by applying water, whereas the exterior was decorated by regularly pasting or stamping in parallel with a lattice design. It can be presumed that the finished jar-coffin was not moved, but the ceiling and walls were built around it as a kiln, for the jar-coffin to be oxidized or to reduce the flame condition in a temperature approximately $700~1,200^{\circ}C$The results from the research, however, show limitations to exploit the exact manufacturing method, therefore there is a need for in-depth examinations: mineralogical investigation on a large amount of jar-coffin samples through a polarized light microscope; substance analysis using various equipments; speculation on the temperature in the place of production and the flame inside.

• Journal of Practical Engineering Education
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• v.7 no.1
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• pp.77-80
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• 2015

Vocational training efficiency and participation was intended to try to find a reliable demand survey methods to find ways that can be maximized. The exact demand investigation may be the most important factor that can improve the quality of training. Furthermore, the training is due to inaccurate demand as research shows the result of ineffective training because of low participation. Four methods of demand survey are used in the form of large mail, telephone, electronic and face-to-face. This paper describes the demand survey that has been carried out through the training of human resources in the training business that suits description local industry human resource development (HRD) consortium of Mokpo University country, proposed a method of effective demand survey.

• The Transactions of the Korea Information Processing Society
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• v.7 no.9
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• pp.3029-3036
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• 2000

Image segmentation is one of the important processes in the image information extraction for computer vision systems. The fuzzy clustering methods have been extensively used in the image segmentation because it extracts feature information of the region. Most of fuzzy clustering methods have used the Fuzzy C-means(FCM) algorithm. This algorithm can be misclassified about the different size of cluster because the degree of membership depends on highly the distance between data and the centroids of the clusters. This paper proposes a fuzzy clustering algorithm using the Average Intracluster Distance that classifies data uniformly without regard to the size of data sets. The Average Intracluster Distance takes an average of the vector set belong to each cluster and increases in exact proportion to its size and density. The experimental results demonstrate that the proposed approach has the g

• Journal of radiological science and technology
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• v.14 no.1
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• pp.61-72
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• 1991

In this paper, the rotating plate method extracting signal and reconstructing original image was proposed. The rotating methode has cell detector array each of which has used in the medical diagnosis X-ray photography. The major problem using the simple horizontal moving or non-moving methode is the size and number of detector cells which have the considerable affection on the sharpness and resolution of the reconstructed image. Secondary, the estimated pixel values of non-detected real points which are placed between detector cells will be the distorted pixels in the reconstructed image. Therefore, the proposed rotating plate method has the exact distribution on the uncertain pixels which were reconstructed by conventional methods to solve there problems. And then, the image using the rotated plate's cell out put signal was reconstructed on the computer simulation. The method will rotated the detector array plate to solve the reconstruction from the detector size and number of conventional methods. The result of simulation has estimated the original pixel position and 81 pixel/mm resolution which the reconsiderlation of the detector's moving orientation, the proposed method has 25 pixel/mm resolution. These results have been represented by 3-D computer graphics.

• Journal of computational fluids engineering
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• v.3 no.1
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• pp.11-21
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• 1998

A vorticity-based method for the numerical solution of the two-dimensional incompressible Navier-Stokes equations is presented. The governing equations for vorticity, velocity and pressure variables are expressed in an integro-differential form. The global coupling between the vorticity and the pressure boundary conditions is fully considered in an iterative procedure when numerical schemes are employed. The finite volume method of the second order TVD scheme is implemented to integrate the vorticity transport equation with the dynamic vorticity boundary condition. The velocity field is obtained by using the Biot-Savart integral. The Green's scalar identity is used to solve the total pressure in an integral approach similar to the surface panel methods which have been well established for potential flow analysis. The present formulation is validated by comparison with data from the literature for the two-dimensional cavity flow driven by shear in a square cavity. We take two types of the cavity now: (ⅰ) driven by non-uniform shear on top lid and body forces for which the exact solution exists, and (ⅱ) driven only by uniform shear (of the classical type).

• Fisheries and Aquatic Sciences
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• v.4 no.3
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• pp.144-149
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• 2001

In other to establish the exact determination method of amino nitrogen (AN) in salt-fermented fish sauces, we determined the AN in fish sauces according to the measuring methods and also investigated the main factors influencing on determination method of AN. AN in salt-fermented anchovy sauce increased linearly as fermentation progressed, and was shown the highest amount measuring by the Formol method, followed by the trinitrobenzene sulfonic acid (TNBS) method and the Copper-salt method. AN concentration in anchovy sauces fermented for 12 months was $88.2\%$ and $77.6\%$ for the TNBS method and the Copper-salt method, respectively, on the basis of Formol method. The ratio of AN/total nitrogen (TN) in anchovy sauce fermented for 12 months was higher than that in commercial anchovy sauces. The determination of AN in anchovy sauce by the TNBS method was not affected by salt concentration, and slightly affected by heating. The effect of MSG on AN contents by Copper-salt method was shown higher than those by the Formol method and the TNBS method. The TNBS method was adaptable to measure the content of AN in fish sauce by this study.

• Journal of Pharmaceutical Investigation
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• v.40 no.1
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• pp.59-61
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• 2010

This study was carried out to establish standard analytical method of Hippocastani Semen extract. Each standard analytical methods were covered for exact and efficient analytical method. Consequently, analytical method of Deutsches Arzneibuch has been adopted for Hippocastani Semen extract. Analytical methods established in this study could be applied to a reasonable and unified quality control of Hippocastani Semen extract.

• The Journal of Korea Robotics Society
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• v.8 no.4
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• pp.283-291
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• 2013

Methods for measuring or estimating of ground shape by a laser range finder and a vision sensor(exteroceptive sensors) have critical weakness in terms that these methods need prior database built to distinguish acquired data as unique surface condition for driving. Also, ground information by exteroceptive sensors does not reflect the deflection of ground surface caused by the movement of UGVs. Thereby, UGVs have some difficulties regarding to finding optimal driving conditions for maximum maneuverability. Therefore, this paper proposes a method of recognizing exact and precise ground shape using Inertial Measurement Unit(IMU) as a proprioceptive sensor. In this paper, firstly this method recognizes attitude of a robot in real-time using IMU and compensates attitude data of a robot with angle errors through analysis of vehicle dynamics. This method is verified by outdoor driving experiments of a real mobile robot.