• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.375-381
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• 2004

Recently, the evolution in production techniques (e.g. high-speed milling) and the complex shapes involved in modem production design has been increasingly popular. The key to the achievement is a drastic improvement of the dynamic behavior of the machine tool axes used in production machinery. The more complex these tool paths the higher the speed and acceleration requirements. But it is very difficult to reach the target for high speed machine tool because of the limitations of servo system and motion control system. However the direct drive design of machine tool axes, which is based on linear motors and which recently appeared on the market, is a viable candidate to meet the ever increasing demands, because of these advantages such as no backlash, less friction, more mechanical simplicity and very higher acceleration and velocity comparing to the traditional system. This paper focused on the performance tests of the high speed horizontal machine tool based on linear motor. Especially, dynamic characteristics were investigated through circular test and circular form machining test is carried out considering many important parameter. Therefore these several experiments is used to be evaluated the model for prediction of circular motion error and circular machined error.

• International Journal of Contents
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• v.11 no.3
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• pp.47-53
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• 2015

Visual object tracking is a fundamental problem in the field of computer vision, as it needs a proper model to account for drastic appearance changes that are caused by shape, textural, and illumination variations. In this paper, we propose a feature-based visual-object-tracking method with a sparse representation. Generally, most appearance-based models use the gray-scale pixel values of the input image, but this might be insufficient for a description of the target object under a variety of conditions. To obtain the proper information regarding the target object, the following combination of features has been exploited as a corresponding representation: First, the features of the target templates are extracted by using the HOG (histogram of gradient) and LBPs (local binary patterns); secondly, a feature-based sparsity is attained by solving the minimization problems, whereby the target object is represented by the selection of the minimum reconstruction error. The strengths of both features are exploited to enhance the overall performance of the tracker; furthermore, the proposed method is integrated with the particle-filter framework and achieves a promising result in terms of challenging tracking videos.

• Preventive Nutrition and Food Science
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• v.20 no.3
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• pp.162-168
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• 2015

Lotus (Nelumbo nucifera Gaertn.) seed is widely used as a traditional medicine in countries of Asia. Among many functions of the lotus seed, one interesting activity is its skin protection from the sunlight and scar. In this study, we focused on the skin protective property of lotus seed tea against ultraviolet B (UVB) irradiation. Two groups of a hairless mouse model, water as control (water group) and lotus seed tea (LST group), were administrated a fluid drink water for six months. After 6 month of administration, UVB exposure was carried out to both groups for another 3 months. During and after the administration, the skin moisture content and the morphological and histopathological analyses through biopsy were carried out. Prior to UVB irradiation, no significant difference was discovered in the skin moisture content for the water group and LST group (P<0.05). However, drastic changes were observed after the UVB treatment. The LST group showed a clear evidence of skin protection compared to the control group (P<0.05). The moisture content, epidermal and horny layer thickness, and protein carbonyl values all revealed that the intake of the lotus seed tea enhanced protection against UVB exposure. As a result, the long-term intake of the lotus seed tea showed the effect of preventing loss of skin moisture, mitigating the formation of abnormal keratinocytes, and contributing to protein oxidation inhibition.

• Asia Pacific Journal of Business Review
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• v.1 no.2
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• pp.1-16
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• 2017

The fundamental goal of the research was to verify if the Twin Deficits Hypothesis holds for the economy of Zambia using time series data from 1980-2014. The current account and budget deficit were employed as key variables. The exchange rate was also used as a transmission mechanism to see how it contributes in the nexus. Cointegration tests confirmed a long run association of the variables. After fitting the VECM model, Granger causality tests confirmed the existence of twin deficits for Zambia. The results supported uni-directional reverse causality. The exchange rate was shown to be more significant in the long run than in the short run. The implosion of the time series as shown by the predicted cointegration equation implies that unless drastic measures are taken to cure the deficits, using the current account as the major target variable, twin deficits will persist for some time. The major policy implication of this research is that given that Zambia is a primary commodity-dependent developing country subsisting largely on copper revenues to sustain the economy, there is a need to move away from "copper addiction," given the recent volatility of earnings of primary commodities (e.g. through diversification of the economy, import substitution, and other strategies).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.142-145
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• 2001

I did research or design technology of(integration) network of PSTN and PSDN in this paper. Network structure model in association with soft switching and access gateway can create various services based on web and live time and service fee at the rate of bandwidth which can't be provided by existing network based on SONET. Also, interns of capability(function) of each area and construction of local network subscribers, it has great recovery capability by separating each network as local areas. It indicates that it can additionally maximize the application of its own communication network and drastic reduction of communication cost because it is alternated to exclusive usage cost.

• The Transactions of the Korea Information Processing Society
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• v.7 no.3
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• pp.943-952
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• 2000

The surface reconstruction problem from a set of wire-frame contours is very important in diverse fields such as medical imaging or computer animation. In this paper, surface triangulation method is proposed for solving the problem. Generally, many optimal triangulation techniques suffer from the large computation time but heuristic approaches may produce very unnatural surface when contours are widely different in shape. To compensate the disadvantages of these approaches, we propose a new heuristic triangulation method which iteratively decomposes the surface generation problem from a band (a pair of vertices chain) into tow subproblems from two sub-bands. Generally, conventional greedy heuristic contour triangulation algorithm, suffer from the drastic error propagation during surface modeling when the adjacent contours are different in shape. Our divide-and-conquer algorithm, called band partitioning algorithm, processes eccentric parts of the contours first with more global information. Consequently, the resulting facet model becomes more stable and natural even though the shapes are widely different. An interesting property of our method is hat it supports multi-resolution capability in surface modeling time. According to experiments, it is proved to be very robust and efficient in many applications.

• Journal of Multimedia Information System
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• v.8 no.2
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• pp.93-100
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• 2021

Under the time-varying temperature, the high-temperature radiation of forgings and the change of reflection characteristics of oxide skin on the surface of forgings lead to the difficulty of obtaining images to truly reflect the geometric characteristics of forgings. It is urgent to study the clear and reliable acquisition method of hot forging feature image under time-varying temperature to meet the requirements of visual measurement of hot geometric parameters of forgings. Based on this, this chapter first puts forward the quality evaluation method of forging feature image, which provides guarantee for the accurate evaluation of feature image quality. Furthermore, the factors that affect the image quality, such as the radiation characteristics of forgings and the photographic characteristics of cameras, are analyzed, and the imaging spectrum which can effectively suppress the radiation intensity of forgings is determined. Finally, aiming at the problem that the quality of image acquisition is difficult to guarantee due to the drastic change of radiation intensity of forgings under time-varying temperature, an image acquisition method based on minimum signal-to-noise ratio (SNR) based laser light intensity adaptation is proposed, which significantly improves the definition of feature light strips in forging images at high temperature, and finally realizes the clear acquisition of feature images of large-scale hot forging under time-varying temperature.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.6
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• pp.11-21
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• 2022

The perspectives on aging women's financial security during their retirement years are based on their behavior, planning, and decision-making processes during their working years. Elderly women are considered vulnerable and have a longer life expectancy, lower-income, and limited financial understanding compared to males; therefore, drastic steps need to be taken to improve their financial stability and quality of life. The current study sought to determine the most important contributors to retired women's financial health by measuring the value of four factors/variables: capability, opportunity, willingness, and biopsychosocial. This study used a mixed model approach, with qualitative analysis in the first phase involving a focus group discussion session, a pilot analysis, and quantitative analysis for phase two involving the distribution and collection of questionnaires completed by retired women. The surveys were distributed across Malaysia in five distinct zones and yielded 339 usable replies to support the theory. The outcomes of the Multiple Regression Analysis in Malaysia revealed that capability, opportunity, and biopsychosocial factors are significant predictors of retired women's financial security, whereas the willingness indicator lacked statistical significance.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.18 no.2
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• pp.229-251
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• 2007

The change in information technology demands drastic change in digital library service. This study defines what a social semantic digital library should consist of and proposes a new architecture that incorporates core functions needed in designing a SSDL. The SSDL supports semantic information processing based on metadata and ontology and is an innovation system that allows SSDL users to participate in generating new knowledge by interacting with existing metadata and ontology structures. This study designed a SSDL model that consists of five horizontal and two vertical structures.

• Korea Trade Review
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• v.47 no.2
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• pp.133-154
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• 2022

The Baltic Capesize Index (BCI), which is used as an indicator for marine transportation of steel raw materials, is one of the key economic indexes for managing the risk of loss due to rapid market fluctuations when steel companies establish business strategies and procuring plans for raw materials. Still, the conditions of supply and demand of steel raw materials has been extremely affected by volatility shocks from drastic events like the financial crisis such as the Lehman Brothers incident and changes in the external environment such as COVID-19. And, especially since the 2008 financial crisis, endeavors to predict the market conditions of the steel raw material is becoming more and more arduous for the deepening uncertainty and increased volatility of BCI, which has been used as a leading indicator of the real economy. This study investigates the correlation between the steel raw material market and the marine transportation market by estimating the spillover effect of information between markets. The vector error correction model (VECM) was used to analyze information transfer based on the correlation between the BCI and crude steel production, capesize fleet supply, raw material price, and cargo volume.