• Journal of Digital Convergence
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• v.7 no.2
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• pp.35-41
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• 2009

The information technology, in the digital economy era, does a very important role not only for the country's administrative management innovation but also for the business and for the everyday life. Specifically, the e-business for the company or organization is defined as "using the Internet and IT, rescheduling of business process management activities to increase productivity and efficiency and to create new business opportunities." Thanks to the Korea's recent efforts, overall level of informatization and digitalization is able to receive high praise. But the e-business readiness (e-readiness) level is still expected a lot of room for improvement. In this paper, I try to analyze the informatization level of Korea's by the EIU's e-business readiness index and IT industry competitiveness index, to prepare a full-scale e-business era of global competitiveness through any preparation that could do to improve the situation from the analysis of statistical data.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.3
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• pp.270-277
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• 2012

This paper presents a new DAC design strategy to achieve a wideband dynamic linearity by increasing the bandwidth of the output impedance. In order to reduce the dominant parasitic capacitance of the conventional matrix structure, all the cells associated with a unit current source and its control are stacked in a single column very closely (stacked unit cell structure). To further reduce the parasitic capacitance, the size of the unit current source is considerably reduced at the sacrifice of matching yield. The degraded matching of the current sources is compensated for by a self-calibration. A prototype 6-bit 3.3-GS/s current-steering full binary DAC was fabricated in a 1P9M 90 nm CMOS process. The DAC shows an SFDR of 36.4 dB at 3.3 GS/s Nyquist input signal. The active area of the DAC occupies only $0.0546mm^2$ (0.21 mm ${\times}$ 0.26 mm).

• Journal of Mechanical Science and Technology
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• v.20 no.12
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• pp.2087-2093
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• 2006

In this paper, auto focus actuator, which is used to move a lens module in the mobile phone having a camera module, is developed. Camera module containing auto focus actuator requires to minimize total size because of characteristics of the application area such as mobile phone, digital camera, and personal digital assistant. There are stepping motor, voice coil motor, and piezoelectric motor as auto focus actuator. In this paper, voice coil motor having new electromagnetic configuration is proposed. And actuator using proposed voice coil motor is developed by optimal design method using magnetic circuit analysis. The sectional area of the developed actuator is reduced to 32.4% compared with actuator using general electromagnetic configuration. From the performance test, the developed actuator has moving stroke of 0.64 mm for 2.1 volt, hysteresis of 40 $\mu$m, full stroke current of 54 mA, and unit step motion of 3 $\mu$m.

• Journal of Engineering Education Research
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• v.13 no.5
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• pp.66-71
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• 2010

Recently, engineering work become very important for the leaders of the information society for the future knowledge in the 21st century and the goal of engineering education is to prepare people to practice engineering as a profession and also to spread technological literacy, increase student interest in technical careers through science and math education. The College of Engineering (COE) of Korea Maritime University (KMU) aims to be the center of both IT-related high industrial technology and the industries related to port, shipbuilding and the ocean. Especially COE focuses on the educational principles to contribute to the development of the country and the regional communities by educating specialists that have international competitiveness. With the need to expand international collaboration in terms of engineering work, it is proposed to initiate a new state of the Asian-Pacific body of engineering conference. To the extent possible the basic discussion was made to expose elements and supports as full-scale illustration of the engineering conference. The result is a body that evokes multi agreement and joint declaration among members.

• Communications of the Korean Mathematical Society
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• v.11 no.4
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• pp.1159-1174
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• 1996

The spectrum of the Laplacian matrix of a graph gives an information of the structure of the graph. For example, the product of non-zero eigenvalues of the characteristic polynomial of the Laplacian matrix of a graph with n vertices is n times of the number of spanning trees of that graph. The characteristic polynomial of the Laplacian matrix of a graph tells us the number of spanning trees and the connectivity of given graph. in this paper, we compute the characteristic polynomial of the Laplacian matrix of a graph bundle when its voltage lie in an abelian subgroup of the full automorphism group of the fibre; in particular, the automorphism group of the fibre is abelian. Also we study a relation between the characteristic polynomial of the Laplacian matrix of a graph G and that of the Laplacian matrix of a graph bundle over G. Some applications are also discussed.

• Journal of Korean Society for Quality Management
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• v.36 no.2
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• pp.28-35
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• 2008

This study deals with an Excel-based scheduling system for a small and medium sized manufacturing factory without sufficient capability for managing full-scale information systems. The factory has the bottleneck with identical machines and unique batching characteristics. The scheduling problem is formulated as a variation of the parallel-machine scheduling system. It can be solved by a two-phase method: the first phase with an ant colony optimization (ACO) heuristic for order grouping and the second phase with a mixed integer programming (MIP) algorithm for scheduling groups on machines.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.4
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• pp.114-120
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• 2000

Burr is an unavoidable and undesirable by-product of most metal cutting or shearing operations. This burr must be removed to improve the fit of machined parts and safety of workers, to improve the effectiveness of finishing operations. Despite the full or partial automation of FMC or FMS, deburring operations to obtain workpiece with fine surface quality are difficult to be automated since the occurrence and condition of burr are not constant. This study focused on developing a software for deburring automation, which includes automatic recognition of parts, generation of deburring tool path and NC code, by analyzing the IGES format file which contains information of part geometry. The successful performance of developed software was demonstrated by computer simulation and deburring experiment using miniature end brush. And, this research can provide a basis for further advanced studies for automated deburring applications.

• Journal of the military operations research society of Korea
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• v.2 no.1
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• pp.185-194
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• 1976

A terminal response time analysis for a general class of terminals-to-computer subsystem is presented in this paper. On the point of the front view, it should be considered for R.O.K. Military Defense to set up the communication network in order to facilitate for the currency of the information and the data communication system. The model used to study is based on the advanced data communications system in which terminals are connected to Terminal Control Units(TCU) that are in turn connected to local Front-End Processor(FEP). The line control procedures used to interface a TCU and an FEP may be half-duplex Binary Synchronous Communication(BSC), half-duplex Synchronous Data Link Control(SDLC), or full-duplex SLDC. This paper will contribute to facilitate the initial phase of system design and configuration for the Military Defense Communication Network System in future.

• Journal of the Korea Computer Industry Society
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• v.5 no.9
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• pp.987-992
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• 2004

There is the temporal correlation of the video sequence between the motion vector of current block and the motion vector of previous block. In this paper, we propose the improved diamond search pattern using an motion vector prediction candidate search point by the predicted motion information from the same block of the previous frame. Simulation results show that PSNR(Peak-to-Signal Noise Ratio) values are improves as high as high as 14~24% in terms of average number of search point per motion vector estimation and improved about 0.02~0.37dB on an average except the full search(FS) algorithm.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.6 s.183
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• pp.143-150
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• 2006

Recently, in proportion to increased demand on environmentally-friendly heat source, efficient management of district heating(DH) system becomes one of important issue. The objectives of this paper are to systematize data processing of transition temperature, investigate the effect of temperature variations on thermal fatigue and find out a way to improve design fractures of Korean DH pipes. For this purpose, reliable fatigue lift evaluation procedures are examined and applied to quantify thermal fatigue lives. Also, as a prototypal optimization analysis results, mean value of original cross sectional area of selected pipes was reduced 18.6% sustaining their sufficient margins against fatigue failure. So, it is anticipated that the output of this research can be used as useful information of optimal design and operation in the future.