• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1066-1069
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• 2004

Recently the monitoring system of tool setup in high speed precision machining tool is required for manufacturing products that have highly complex and small shape, high precision and high function. It is very important to reduce time to setup tool in order to improve the machining precision and productivity and to protect the breakage of cutting tool as the shape of product is smaller and more complex. Generally, the combination of errors that geometrical clamping error of fixing tool at the spindle of machining center and the asynchronized error of driving mechanism causes that the run-out of tool reaches to 3∼20 times of the thickness of cutting chip. And also the run-out is occurred by the misalignment between axis of tool shank and axis of spindle and spindle bearing in high speed rotation. Generally, high speed machining is considered when the rotating speed is more than 8,000 rpm. At that time, the life time of tool is reduced to about 50％ and the roughness of machining surface is worse as the run-out is increased to 10 micron. The life time of tool could be increased by making monitoring of tool-setting easy, quick and precise in high speed machining center. This means the consumption of tool is much more reduced. And also it reduces the manufacturing cost and increases the productivity by reducing the tool-setup time of operator. In this study, in order to establish the concept of tool-setting monitoring the measuring method of the geometrical error of tool system is studied when the spindle is stopped. And also the measuring method of run-out, dynamic error of tool system, is studied when the spindle is rotated in 8,000 ∼ 60,000 rpm. The dynamic phenomena of tool-setup is analyzed by implementing the monitoring system of rotating tool system and the noncontact measuring system of micro displacement in high speed.

• Wind and Structures
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• v.8 no.5
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• pp.343-356
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• 2005

Overhead sign support structures number in the tens of thousands throughout the trunk-line roadways in the United States. A recent two-phase study sponsored by the National Cooperative Highway Research Program resulted in the most significant changes to the AASHTO design specifications for sign support structures to date. The driving factor for these substantial changes was fatigue related cracks and some recent failures. This paper presents the method and results of a subsequent study sponsored by the Michigan Department of Transportation (MDOT) to develop a relative performance-based procedure to rank overhead sign support structures around the United States based on a linear combination of their expected fatigue life and an approximate measure of cost. This was accomplished by coupling a random vibrations approach with six degree-of-freedom linear dynamic models for fatigue life estimation. Approximate cost was modeled as the product of the steel weight and a constructability factor. An objective function was developed and used to rank selected steel sign support structures from around the country with the goal of maximizing the objective function. Although a purely relative approach, the ranking procedure was found to be efficient and provided the decision support necessary to MDOT.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.4
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• pp.419-429
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• 2022

The aim of this research is to examine how globalization affects coffee exports in the producing countries. This research used secondary data obtained from the International Coffee Organization, Pen World Table, World Bank, Food and Agricultural Organization, and KoF Globalization Index to achieve its goals. We used secondary data from 1990 to 2018 from various foreign databases. The research used a two-step system GMM (sys-GMM) to analyze the effect of globalization on coffee export in twenty-four producing countries. We found that export lag, gross domestic product (GDP), exchange rate, and the political globalization index (PGI) positively and significantly impact coffee exports. Meanwhile, coffee exports were unaffected by the level of export prices and the human capital index. Surprisingly, the trade globalization index has a negative impact on coffee exports. This demonstrates the unpreparedness of coffee-producing countries to face tough competition in trade globalization. The political globalization index, the final variable, has a positive impact on exports. With the opening up of world politics, it seems that the environment of democracy in producing countries is increasing. As a result, governments in these countries have adopted a policy of aggressively supporting coffee exports.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.7 s.178
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• pp.1779-1786
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• 2000

Most of traditional design processes of mechanical parts are regarded as sequential and discrete, since different kinds of softwas should be introduced. In this paper, we develop an integrated fram ework for virtual design and performance testing of an automobile seat. The system is composed of four modules, i.e. CAD, static analysis, dynamic analysis, and draft drawing module. In the CAD module, PRO/ENGINEER 3D seat model is created using parameters to be modified with the result of static and dynamic analysis. In the static analysis, headrest tere used in each design stage make it difficult to feedback their results to upstream process. These discrete processes may result in time loss and cost rise. In recent years, life cycle of product is reduced. To have competence with others, new concept design processt is simulated using ANSYS. In the dynamic analysis module, FMVSS201 test is simulated using DADS. Overall data flow is controlled by Motif. The advantage of the system is that even a novice can perform and review the whole design process, without a good hand at professional design/analysis S/W in each stage. The system also provides a virtual design space, where engineers in different development stage can access common data of design models. The concept could be applied to other fields and it could reduce time and money required in design process.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.11 no.1
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• pp.17-24
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• 2005

During handling unitized products, they are subjected to a variety environmental hazards. Shock and vibration hazards are generally considered the most damaging of the environmental hazards on a product, and it may encounter while passing through the distribution environment. A major cause of shock damage to products is drops during manual handling. The increasing use of unitization on pallets has been resulted in a reduction in the manual handling of products and with it a reduction in the shock hazards. This has caused and increasing interest in research focused on vibration caused damage. the use of pallets as a base for unitizing loads, aids in the mechanical handling, transportation and storage of products. Besides aiding in the handling, transportation and storage of products, a pallet also acts on and interface between the packaged goods and the distribution environment. The determination of the impact deformation of the cushioning materials such as tray cup (polymeric foam) and corrugated fiberboard pad must be carried out to design the proper packaging system providing adequate protection for the fruit, and to understand the complex interaction between the components of fruit when they relate to expected transportation vibration inputs. In this study, the theoretical analysis of impact deformation for cushioning materials by dynamic vibration. The impact deformations of SW and DW corrugated fiberboard pad in acceleration amplitudes of 0.25 G-rms and 0.5 G-rms that were usually generated in transport vehicles during distribution environments were very small compare with the thickness of corrugated fiberboard pad. The maximum of vibration acceleration level of tray cup by vibration impact was about 3.2 G-rms. The theoretical allowable acceleration (G-factor) of the pear was 0.7102 G-rms, and the maximum dynamic deformation estimated within G-factor was about 1 mm.

• Information Systems Review
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• v.10 no.2
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• pp.195-209
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• 2008

Customers' needs change every moment. Profitability of stores can't be increased anymore with an existing standardized chain store management. Accordingly, a personalized store management tool needs through prediction of customers' preference. In this study, we propose a recommending procedure using dynamic customers' preference by analyzing the transaction database. We utilize self-organizing map algorithm and association rule mining which are applied to cluster the chain stores and explore purchase sequence of customers. We demonstrate that the proposed methodology makes an effect on recommendation of products in the market which is characterized by a fast fashion and a short product life cycle.

• The Research Journal of the Costume Culture
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• v.18 no.5
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• pp.809-823
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• 2010

The 21st century is the age of culture and sensitivity. As the interest in the art and culture grows, Artygen who prefers artistic designs grow in number. The desire to enjoy life from the increase of leisure time and financial afford ability created a new trend of party culture. This study analyzes the characteristics of Artygen who pursues artistic sense and sensitivity and suggests party-wear designs that please Artygen and accentuate individuality and personal preferences in a party, which is a type of popular entertainment these days. Through literature review, the background of Artygen and party was examined; First, in order to analyze the feature of art designs, photos of products that were in fashion from 2007 to 2009, (during which the term, 'Artygen', was coined) were collected. Second, in order to analyze the party-wear designs, photos of party-wear in wine party and club party popular among young people in the 20~30's were collected. Through the analysis, the party-wears targeting Artygen was developed based on the characteristics of popular art designs. The results of this study were as follows. First, from the result of analyzing the art design shown in product, casual, romantic, modern, dynamic and gorgeous images were. Second, art design shown in fashion, casual, romantic, chic, dynamic and gorgeous images were. Third, in wine party, romantic, elegant, gorgeous and formal images were in order and in club party, casual, gorgeous, chic and romantic images were in order. Fourth, the study displayed design by connecting aesthetic factor of artistic design to 2 wine party-wear of romantic and gorgeous images and 3 club party dresses of casual, gorgeous and chic images.

• Korean Business Review
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• v.11
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• pp.15-38
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• 1998

This study explores the evolution of technical innovation over time. It focuses on sectors of the information technology because this industry can be referred to as one of the most dynamic industries of all times. Following evolutionary theorists, we argue that technological change is gradual and that superior firms and technologies are reward by the' selection' environment. In the initial phase of the industry life cycle, technological change is expected to be radical and uncertainty is high. Over time a product or technology is likely to arise which stands out above all other products or technologies. These so-called 'basic designs' serve as sorts of 'technological guideposts' for further developments in the technology. Once a basic design established, technological progress tends to follow consistent paths or trajectories. The cumulative character of technological progress facilitates a rapid expansion of the boundaries of the technology until the natural limits of the technology are approached and technological progress slows down. Following ecological theories, supply-side developments in the industry are described on the basis of five different organizational types. On the basis of this pattern of market and technological evolution we came up with seven basic propositions.

• The Journal of Economics, Marketing and Management
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• v.7 no.1
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• pp.1-14
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• 2019

Purpose - Currently, the economic globalization has become a common channel for China's enterprise to perform the international economic activities. Due to this background, this paper tries to analyze the influence of internationalization level on operation performance of enterprises. Research design, data, and Methodology - This paper aims at 296 companies going listed in Shanghai Stock Exchange and Shenzhen Stock Exchange. The data about the listed companies during the 12 years from 2005 to 2016 have been collected. Relevant theories, including the theory of comparative advantage, monopolistic advantage and product life cycle in developed countries as well as the small scale technology and state on localized technological capacities in developing countries, have been summarized to provide theoretical basis for the influence of international operation on operation performance of the enterprises. Moreover, the current status of international operation of China's enterprises, including the dynamic cause of the internationalization of China's enterprises, its competitive advantage and disadvantage as well as the interest and potential risk of the internationalization, have been also analyzed. Results - Via adopting the panel data to conduct an empirical analysis, It can be found that the relationship between international operation level and operation performance of China's enterprises can be expressed as the S-curve of declining, rising and declining again. Conclusions - This paper has taken the lead in using Ohlson corporate value model to fill the gap in the relevant researches in China. It can also provide guidance for the international operation of China's enterprises. Meanwhile, the two systems for international operation and performance evaluation index have been put forward. The performance of international operation can be classified as financial performance or corporate value so that the operation effect of those China's enterprises going abroad can be better evaluated.

• The Journal of the Korea Contents Association
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• v.21 no.6
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• pp.588-597
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• 2021

In Korea, the standard for calculating the profit of a general insurance, which constitutes the loading in the premium, is not specified, and most of the non-life insurance companies reflect 2~5% of the premium as profit margin. Although the transparency of pricing is required due to the nature of insurance products, there are insufficient standards and empirical studies on the determination of insurance price factors in the domestic insurance industry. In this study, we propose a method of calculating the expected profit margin of general insurance. A way for calculating the expected profit margin of the general insurance is to reflect the shareholder demand on the capital that the insurance company should secure against the risk of loss due to the profit/loss volatility, as a ratio to the insurance premium. Shareholders should be compensated for the risks associated with their insurance operations, and the opportunity cost of these shareholders is to be reflected in premiums. In this study, we calculate the amount of capital that the company should accumulate to prepare insurance risk for each product, and insurance risk is defined as the volatility of insurance operating profit/loss. And insurance risk is calculated using stochastic simulation based on Dynamic Financial Analysis (DFA) methodology. Finally, we calculate the expected profit margins for 25 products and analyzed the difference between those and the profit ratio of domestic general insurance.