• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2011년도 춘계학술발표대회 논문집
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• pp.21-26
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• 2011

Initial reliability prediction done by calculation would be more practical if support by evidence from customer usage profile and field failure data to improve the prediction. Thus, the consistency of the design and the product would be practically validated. In this paper, it will address rationale and method to decide on Acceleration Factor (AF) to be used in Accelerated Life Test (ALT) through usage profile and field failure. The case study of tractor transmission is used to demonstrate the method which data obtained from surveys done on farmers, field visits and field failure data from service center. By considering all the elements, it will determine more relevant AF which indicates the real use conditions of the component.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.1028-1032
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• 2005

Life cycle assessment(LCA) has been developed from the concept of life cycle thinking. Life cycle thinking implies that everyone in the whole chain of a product's life cycle, from cradle to grave, has a responsibility and a role to play, taking into account all the relevant external effects. LCA is an analytical tool for identifying environmental loads and assessing the environmental impact in the whole chain of a product's life cycle. In Europe and Japan, LCA and ecodesign study for railway industry have been actively carried out recently. However, LCA for railway industry in domestic is still infant. LCA is standardized in International Organization of Standardization(ISO), base on the ISO 14040 standards, 307 life cycle inventory(LCI) database for infrastructure and base materials have been established in total since 1999. Some of LCI database can use in performing LCA for trains and railway infrastructure, but still not enough to derive accurate LCA result. Therefore, railway oriented LCA methodology and LCI DB are needed to be developed.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제17권4호
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• pp.238-266
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• 2013

The Interaction Picture (IP) method is a valuable alternative to Split-step methods for solving certain types of partial differential equations such as the nonlinear Schr$\ddot{o}$dinger equation or the Gross-Pitaevskii equation. Although very similar to the Symmetric Split-step (SS) method in its inner computational structure, the IP method results from a change of unknown and therefore do not involve approximation such as the one resulting from the use of a splitting formula. In its standard form the IP method such as the SS method is used in conjunction with the classical 4th order Runge-Kutta (RK) scheme. However it appears to be relevant to look for RK scheme of higher order so as to improve the accuracy of the IP method. In this paper we investigate 5th order Embedded Runge-Kutta schemes suited to be used in conjunction with the IP method and designed to deliver a local error estimation for adaptive step size control.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.206-211
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• 2000

Demands on a quiet environment is increasing because of noisiness and annoyance due to the extended use of noisy electronic device. Determination of sound power levels of noise sources using sound pressure in a reverberation room is usually a relevant method for devices with comparatively large volume or unevenly distributed source position. This study aims to observe the contents of ISO 3741 and analyze its changes in the revised standard ISO 3741-1999. And also aims to assess the revised ISO 1999 its effectiveness and limitations with an actual application to measure the sound power level of a refrigerator.

• Communications for Statistical Applications and Methods
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• 제20권4호
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• pp.301-309
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• 2013

This paper predicts gross box office revenue for domestic films using the Korean film data from 2008-2011. We use three regression methods, Linear Regression, Random Forest and Gradient Boosting to predict the gross box office revenue. We only consider domestic films with a revenue size of at least KRW 500 million; relevant explanatory variables are chosen by data visualization and variable selection techniques. The key idea of analyzing this data is to construct the meaningful explanatory variables from the data sources available to the public. Some variables must be categorized to conduct more effective analysis and clustering methods are applied to achieve this task. We choose the best model based on performance in the test set and important explanatory variables are discussed.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.349-353
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• 2008

We present the development of a water-cooled heat sink that provides reliable thermal performance for high-power IGBT inverter. The development process comprises three stages. In the concept design, the thermal performances of two design proposals are considered. The thermal system of each design is particularly analyzed using the compact model. In the detailed design stage, specific dimensions of the heat sink are determined considering the design options under given external restrictions and the results from three-dimensional heat transfer analysis. The prototype of the resultant design is made and tested on the rig for final confirmation. We emphasize the relevant use of the thermal analysis on each stage and also discuss various practical issues involved.

• 대한기계학회논문집
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• 제17권11호
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• pp.2664-2675
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• 1993

In this paper, the effects of chip breaker configuration on cutting forces for various cutting conditions are investigated and a method for predicting cutting forces effectively for chip breaker insert in milling is described. Based on the shear plane model and the relevant equations already existing for the relation among the parameters, the method makes use of the analytic geometric approach considering the configuration of cutting too by a 3-dimensional coordinate transformation matrix. The groove type chip breaker insert is modeled to be a double rake insert, represented by the first radial rake angle, the second radial rake angle and the length of land, and the program analyzing the cutting forces is developed. The program capability is verified by comparing the results with the experimental ones for a single cutter; and in case of primary cutting forces, the results of simulation and experiments agree very well showing 2%~16.7% difference within the feed rate range investigated.

• 유통과학연구
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• 제17권4호
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• pp.17-26
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• 2019

Purpose - Today's companies concentrate intensively on building consumer value and corporate reputation for continuing growth and advancement in an ever-changing global business management environment. This research intended to study the correlation between consumer value and corporate social responsibility (CSR) activities in building corporate reputation with consumers. Research design, data, and methodology - Online and offline surveys were conducted among male and female adults across Korea. Surveys were conducted for three weeks from August 21, 2018 to September 8, 2018. The samples consisted of 350 offline and 112 online surveys, and a combined total of 462 samples was used for final analysis. Result - Higher consumer value means a greater chance that consumers will select that company's products over those of competitors. For competitive advantage purposes, companies use various consumer management strategies to bolster consumer value and corporate reputation with consumers. Conclusions - Brand assets are subject to ethical responsibility, which is a dimension of corporate social responsibility. Of note, one relevant finding about brand assets (similar to findings in previous research) is the existence of confusion about brand recognition and brand image as perceived by customers.

• 무역상무연구
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• 제13권
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• pp.805-833
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• 2000

Electronic commerce facilitates trade and lower transaction cost can help firms make use of the opportunities of globalization of production and markets. Electronic commerce has broad implications for future trade. These implications include the effect on trade policy making and enforcement. And it is important to ensure that the present and future trading system de jure and de facto allows electronic commerce to realize its potentials as an alternative or a complement to conventional trade. The comprehensive work program had been implemented to examine all trade-related issues relating to global electronic commerce before the Seattle 3rd Ministerial Conference which was suspended. In general, Member countries recognized the need to ensure that electronic commerce in all its forms is conducted in full conformity with WTO principles and rules. But, there are still major issues to be solved such as access to relevant electronic systems, competition policy in telecomnunications services, WTO provisions relating to the protection of IPRs, the clarification of a number of key concepts and definitions, etc.

• Asian-Australasian Journal of Animal Sciences
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• 제5권2호
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• pp.309-314
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• 1992

A review of dairy development and crossbreeding programmes in Malaysia since 1953 is undertaken, based on the relevant literature and the writer's experience. The need for higher domestic milk production and the role of crossbreeding in the realization of this objective is explained. A retrospective evaluation is made of the past crossbreeding programmes and of the decision to use temperate dairy breeds for the purpose. Current dairy development under the 'New Economic Policy' of the Malaysian government and the major problems connected with the importation of high-milk producing animals are discussed. To overcome existing constraints, future strategies for crossbreeding and dairy development, based on long-term objectives, are proposed. It is concluded that crossbreeding will only be useful if the introduction of high yielding dairy animals is combined with an improvement of existing husbandry systems.