• Journal of Institute of Control, Robotics and Systems
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• v.14 no.1
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• pp.70-74
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• 2008

In the field of camera motion research, it is widely held that the position (movement) and pose (rotation) of cameras are correlated and cannot be independently separated. A new equation based on inner product is proposed here to independently separate the position and pose. It is proved that the position and pose are not correlated and the equation is applied to estimation of the camera exterior parameters using a real image and 3D data.

• Journal of computational fluids engineering
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• v.21 no.3
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• pp.110-117
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• 2016

It is a essential to minimize production of by-products for economically effective petrochemical process. In order to find key factor to achieve the effective process, 2-dimensional computational fluid dynamics considering a variety of physics such as convective and radiative heat transfer and thermal cracking of ethane are carried out. The reactor is modeled as an isothermal tube, whose length is 1.2 m and radius is 0.01 m, respectively. At first, the axial distribution of representative by-products in ethane thermal cracking are investigated in each inner wall temperature conditions. Then the comparison between concentration of propene($C_3H_6$) and ethane conversion is discussed with respect to inner wall temperature conditions too. Finally, both reaction rate and turbulent kinetic energy are used to identify the production mechanism of $C_3H_6$ under the intersection point in the plot for $C_3H_6$ molar concentration and ethane conversion.

• Phonetics and Speech Sciences
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• v.7 no.4
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• pp.17-25
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• 2015

For blind source separation of convolutive mixtures, FDICA(Frequency Domain Independent Component Analysis) algorithms are generally used. Since FDICA algorithm such as Sawada FDICA, IVA(Independent Vector Analysis) works on the frequency bin basis with a natural gradient descent method, it takes much time to converge. In this paper, we propose a new method to improve convergence speed in FDICA algorithm. The proposed method reduces the number of iteration drastically in the process of natural gradient descent method by applying a weighted inner product constraint of unmixing matrix. Experimental results have shown that the proposed method achieved large improvement of convergence speed without degrading the separation performance of the baseline algorithms.

• Design & Manufacturing
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• v.12 no.1
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• pp.52-57
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• 2018

With the recent strengthening of environmental regulations and the need for cost reduction, excavators, a type of construction equipment, are being miniaturized while components are being developed in consideration of stability. In the case of excavator press parts, mainly high-strength steel sheets are being used to enhance stability and reduce weight. However, in the case of high-strength materials, there is a need to research product forming methods to reduce Springback in defects arising in parts assembly due to Springback that result from the internal residual stress that occurs in press forming being released after product forming. Accordingly, regarding the tank cover, an excavator press-forming part, this study selected a method to reduce distortion through analysis of the Springback occurrence rate and Springback causes through a forming analysis. A forming analysis was conducted for the Springback of the tank cover. Deformations of 13.714 mm in the upper part and 6.244 mm in the inner part of the product occurred, while wrinkles occurred on the sides of the product due to uneven thickness. A forming analysis was conducted for the major shapes of the product to investigate the causes of Springback. Distortion deformation due to the bead in the center of the product was confirmed to be a large factor. A Springback reduction method of correcting uneven thickness in the product sides, a Springback reduction method of removing the bead, and a correction method of restriking after the final forming were used in a forming analysis to determine the degree of Springback reduction. For the forming method to correct uneven thickness in the sides, deformation was reduced by 12% in the upper side compared to the existing model, but deformation in the inner side increased by 1%. For the restriking forming method, deformation decreased by 25% in the upper side and 13% in the inner side. For the bead removal method, deformation decreased by 28% in the upper side and 13% in the inner side, the largest Springback correction results. This indicates that the bead has a large affect on Springback.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.3
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• pp.261-272
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• 2014

Home appliances go through a couple of packaging stages from the plant to consumers. The primary packaging, inner packaging for each part, happens for protection after products leave the plant. The secondary packaging happens in the unit of product, ensuring cushioning packaging to protect products from movement. The final tertiary packaging is for transportation and delivery. Each stage of product packaging, however, costs a lot of money because of disposable packaging materials used in each stage including vinyl, tapes, Styrofoam, and corrugated cardboards. Discarded packaging materials also cause environmental problems. In an effort to come up with a measure to solve those problems, this study proposed a plan to minimize logistics costs with semi-permanent packaging materials to replace disposable ones including Styrofoam, vinyl, and corrugated cardboards in the stages of inner packaging, cushioning packaging, product unit-based packaging, and transportation. The study also developed a model to cut down logistics costs by reducing various packaging stages including the primary, secondary, and tertiary stage only to the secondary one through module-type products instead of the transportation- and delivery-type ones, as well as demonstrated the excellence of the study through numerical analysis.

• The KIPS Transactions:PartB
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• v.16B no.6
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• pp.497-502
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• 2009

In this paper, we introduce an automatic product feature extracting system that improves the efficiency of product review analysis. Our system consists of 2 parts: a review collection and correction part and a product feature extraction part. The former part collects reviews from internet shopping malls and revises spoken style or ungrammatical sentences. In the latter part, product features that mean items that can be used as evaluation criteria like 'size' and 'style' for a skirt are automatically extracted by utilizing term statistics in reviews and web documents on the Internet. We choose nouns in reviews as candidates for product features, and calculate degree of association between candidate nouns and products by combining inner association degree and outer association degree. Inner association degree is calculated from noun frequency in reviews and outer association degree is calculated from co-occurrence frequency of a candidate noun and a product name in web documents. In evaluation results, our extraction method showed an average recall of 90%, which is better than the results of previous approaches.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.2
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• pp.267-278
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• 1998

The purpose of this study was to investigate the degree of self-monitoring (SM), the task situation and the appeal type of advertising impact on consumer behavior: in inner wear purchase. Information for the study was obtained with the use of experimental design. the experimental materials for the study were two-type inner wear advertisements (image appeal Ad/product appeal Ad). The subjects were 270, who were randomly sampled women undergraduate students in Korea, and main-test subjects (70 high SM subjects/69 low SM subjects) were assigned to the cells of 2 (self usage/gift-giving)x2 (quality appeal Ad/image appeal Ad). According to the 2x(2$\times$2) mixed factorial design, the level of SM score, the type of task situation score and the level of appeal type of advertising score were compared and tested by analysis of ANOVA. The results of experiment were as follows: 1. Experimental 1. the results showed the product preference on inner wear was the significant 3-way interaction effects among the degree of SM, the task situation, and the appeal type of advertising as well as the significant main effects of the appeal type of advertising. That is, the situation impact differs from the appeal type of advertising according to the degree of SM. 2. Experimental ll. the results showed the purchase intention on inner wear was the significant 2-way interaction effects between the appeal type of advertising and the task situation as well as the significant main effects of the appeal type of advertising and the task situation. That is, there is considerable difference in gift-giving situation rather than in self- usage situation according to the appeal type of advertising.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.3
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• pp.437-444
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• 2015

Satellite selection and exclusion techniques have been applied to the global navigation satellite system (GNSS) with the aim of achieving a balance between navigational performance and computational efficiency. Conventional approaches to satellite selection based on the best dilution of precision (DOP) are excessively computational and complicated. This paper proposes a new method that applies a geometric sensitivity index of individual GNSS satellites. The sensitivity index is derived using the inner product of the line of sight (LOS) vector of each satellite. First, the LOS vector is computed, which accounts for the geometry between the satellite and user positions. Second, the inner product of each pair of LOS vectors is calculated, which indicates the proximities of the satellites to one another. The proximity can be determined according to the sensitivity of each satellite. A post-processing test was conducted to verify the reliability of the proposed method. The proposed index and the results of a conventional approach that measures the dilution of precision (DOP) were compared. The test results demonstrate that the proposed index produces results that are within 96% of those of the conventional approach and reduces the computational burden. This index can be utilized to estimate the sensitivity of individual satellites, obtaining a navigation solution. Therefore, the proposed index applies to satellite selection and exclusion as well as to the sensitivity analyses of multiple GNSS applications.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.148-151
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• 2003

The purpose of this study is to investigate the manufacturing technique on the U type Draw-Bending of inner groove tube. The U type tube requires the quality of product that satisfy sufficient conditions for a heat exchanger. The mandrel components act the important roles that prevent wrinkles and keep the shape of cross section of bended tube at bending process. We performed the FEM simulation using LS-DYNA software and the bending test of inner groove tube and then, compared bending simulation with bending test results about mandrel ball diameter, mandrel position and optimal clearance between mandrel and tube.

• Transactions of Materials Processing
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• v.8 no.6
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• pp.612-619
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• 1999

Internal and external defects of an inner pulley for automobile air conditioner are investigated in this study. Inner pulley is a part of compressor clutch assembly of automobile air conditioner. In cold forging of inner pulley, the design requirement are to keep the same height of the inner rib and outer one and to make uniform distribution of hardness in the forged product. At the end of the forging of inner pulley, the piping defect as an external defect begins to form at the back center of the billet. The internal crack as an internal defect also occur at the adiabatic shear band which usually has maximum ductile fracture value. It is important to predict when the internal and external defects occur during the deformation process, in order to minimize the amount of discard that is generated. The finite element simulations are applied to analyze the defects. The validity of the computational results are examined by experiments. These computational results are in good agreement with the experimental ones.