• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.301-303
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• 2004

In this work, we develop on-line traffic prediction algorithm for real-time VBR traffic. There are a number of important issues: (i) The traffic prediction algorithm should exploit the stochastic characteristics of the underlying traffic and (ii) it should quickly adapt to structural changes in underlying traffic. GOP ARIMA model effectively addresses this issues and it is used as basis in our bandwidth prediction. Our prediction model deploy Kalman filter to incorporate the prediction error for the next prediction round. We examine the performance of GOP ARIMA based prediction with linear prediction with LMS and double exponential smoothing. The proposed prediction algorithm exhibits superior performam againt the rest.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1115-1119
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• 2007

As in many of the vehicle NVH issues, blower motor noise has been improved over the years through intensive R&D and production process improvement. Durability of motors, however, still has room for improvement according to customer surveys such as VDS. To investigate the noise issues of blower motors in view of durability, current production motors along with major competitor motors are tested. The noise after accelerated durability test shows that production motors are competitive in noise level with similar noise performance compared to initial measurement. The test result also provided guidelines to the durability development process.

• The Korean Journal of Financial Management
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• v.11 no.2
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• pp.175-193
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• 1994

This paper relates the valuation consequences of common-stock, convertible-debt and straight-debt offering announcements to the issuing firms' stock price performance in periods before the announcements. Similar to previous studies on equity offerings, we find that the announcement effects of security offerings, regardless of offering types, are negatively correlated with the short-term pre-offering stock returns. We show that the informational impact of the preceding earnings and dividend(E/D) announcements account for the previous findings of the negative correlation. We further report that security issues following 'good-news' E/D announcements result in larger stock price declines than issues following 'bad-news' E/D announcements. The finding is consistent with the hypothesis that the E/D information affects the investors' assessments of the firm's cash flow expectations and of the probability of external financing.

• Journal of the Korean Operations Research and Management Science Society
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• v.35 no.4
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• pp.17-31
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• 2010

This study investigates two-stage return policy and recycling issues in an e-marketplace supply chain consisting of consumers, a retailer and a manufacturer. The manufacturer, a focal company in the e-marketplace supply chain, considers the recycling of commercial returns so offers the retailer a buy-back contract of which transfer payment consists of a wholesale price and a buy-back price. Then, under the given contract offer, the retailer determines a selling price and a return policy to control consumers' demand and return requests. We consider the retailer's opportunistic behavior and supply chain coordination issues based on the principal-agent paradigm. We compare the first-best and second-best optima and conduct comparative static analyses to evaluate the performance results of the buy-back contract and provide important managerial implications.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.252-269
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• 1995

Organizational decision support systems(ODSS) are a new type of decision support systems(DSS) focusing on the organization-wide issues rather than individual, group, or departmental issues. Because of its organization-wideness, which means an ODSS cuts across organizational functions or hierarchical layers, seamless integration with organization's diverse IS applications running on heterogeneous platforms becomes a critical issue. In this paper, we analyzed the Korea Telecom(KT)'s Operations & Maintenance(O&M) division focusing on its investment strategies. We developed a conceptual framework which links O&M investment to its performance. We also developed a prototype of KTOM-ODSS with an EIS-like user-friendly interface.

• Journal of the Ergonomics Society of Korea
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• v.18 no.3
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• pp.153-169
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• 1999

The design of nuclear control room is advancing toward totally computer based human system interfaces (HSI). Computer based interfaces offer the opportunity to provide improved support of operator performance, but if not properly deployed, can introduce new challenges. This paper reviews the Westinghouse AP-600 Human Factors Verification and Validation Plan selected for HSI evaluation model of Korea next generation nuclear control rooms. The AP-600 HSI evaluation model addressed 15 evaluation issues considering major activity class of operator and task complexity factors. This paper also describes the test procedures experimenters should follow to evaluate the addressed issues.

• Journal of International Society for Simulation Surgery
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• v.2 no.2
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• pp.47-51
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• 2015

Faces play a key role in revealing the personalized attributes such as the identity, emotion, health condition, etc. Due to the importance of faces, computer-assisted face modeling and reconstruction have been actively studied both in computer vision and graphics community. Especially, face reconstruction and realistic face synthesis are well-grounded research problems and various approaches have been proposed during the last decade. In this paper, we discuss a wide range of existing work in face modeling by introducing their target applications, categorizing them upon their methodology and addressing their strength and weakness on performance. Finally, we introduce remaining research issues and suggest the future research direction in face modeling. We believe that this paper provides a high-level overview on face modeling techniques and helps understand the major research issues and the trends of methodology.

• International Journal of Internet, Broadcasting and Communication
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• v.8 no.4
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• pp.58-62
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• 2016

Shipping related services is attracting attention as a UAV (Unmanned Aerial Vehicle) application with the recent economy has been generally accepted drones. UAV of the existing military-driven logistics delivery, aerial photography, wireless Internet connection, broadcasting, disaster research, digital maps, transportation, advertising, meteorological, border surveillance, agricultural use, such as hobbies range of uses from up military are diverse and growing. The advantage of delivery drones seems to be an important feature of delivery of the goods, including labor-saving, long-distance transportation in cold weather. UAV is demanded by competitive performance development for commercialization. Privacy issues that may arise during the drone operation, ensuring marketability issues, control system, regulations, operational standards and specifications, etc. should be addressed. Development direction of Korea UAV based in current technology, regulation, and growth potential presented by deriving from the idea of 'GIF 2016 Gang-won Hackathon.

• 한국전산유체공학회:학술대회논문집
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• 2006.05a
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• pp.35-40
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• 2006

The insatiable desire of consumers to want more and more performance from computer equipment has driven the powers of this equipment to levels that are putting a strain on the thermal management of data centers housing this equipment. Equipment powers have been rising steadily over the past 10 years at a rapid rate. When the industry switched from bipolar to CMOS back in the early 90's industry experts had thought that the low power CMOS technology would resolve all problems associated with power and heat. Little did they know that now the problems associated with the CMOS equipment has surpassed anything installed with the bipolar technologies 10 to 15 years ago. Data centers are being designed with 15 to 20 years life spans and customers we asking how to plan for the power and cooling within these data centers. This paper addresses some of the current issues with cooling of equipment in data centers and describes some of the on-going efforts to under the thermal environment. To set the stage far describing the data center thermal management issues the power trends from the microprocessor to the rack will be described.

• Progress in Medical Physics
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• v.30 no.2
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• pp.39-48
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• 2019

Deep learning has been applied to various medical data. In particular, current deep learning models exhibit remarkable performance at specific tasks, sometimes offering higher accuracy than that of experts for discriminating specific diseases from medical images. The current status of deep learning applications to molecular imaging can be divided into a few subtypes in terms of their purposes: differential diagnostic classification, enhancement of image acquisition, and image-based quantification. As functional and pathophysiologic information is key to molecular imaging, this review will emphasize the need for accurate biomarker acquisition by deep learning in molecular imaging. Furthermore, this review addresses practical issues that include clinical validation, data distribution, labeling issues, and harmonization to achieve clinically feasible deep learning models. Eventually, deep learning will enhance the role of theranostics, which aims at precision targeting of pathophysiology by maximizing molecular imaging functional information.