• ETRI Journal
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• v.28 no.5
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• pp.545-554
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• 2006

A widely tunable multi-channel grating cavity laser is proposed and experimentally demonstrated. The device is implemented in Littman configuration with an echelle grating based on Rowland circle construction and realized by monolithically integrating all elements in an InP substrate. Lasing wavelength is selected by turning on an amplifier and the appropriate channel element in the array, and it is tuned by controlling light deflection electrically. The 6-channel device exhibits a tuning range of about 50 nm with a side mode suppression ratio of more than 30 dB. This is accomplished by adjusting the applied current of the dispersive element and phase control section.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.4
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• pp.14-23
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• 2008

Information Technology (IT) managers play an important role as a bridge between technology and business, and it is therefore important to determine what skills are required for this position. Although many previous studies have investigated the skills necessary for IT managers to perform their roles, most of these studies are based on the data collected from companies in the US. However, given the increased labor mobility in the IT industry, it is important to determine whether IT manager positions elsewhere require the same skills as the positions in the US. This study is a first step in this direction and attempts to determine whether there are any differences in skill requirements between Korean IT managers and American IT managers, and, if so, what they are.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.941-946
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• 2006

It followed in system development and SMRT(Seoul Metropolitan Rapid Transit Co)System reached to an automatic train operation(ATO) and driverless operation(DLM) from the manual operation due to the train driver. The train like the general bus or the car vehicle was not serial riding in a car and the Parallel concept which the numerous passenger rides in a car simultaneously occur frequently the charge of the train driver unmanned bitterly from existing manual handling was a possibility of doing, train open door control(ODM) which bites also ATO, it handles it minimized. Like this ATO/DLM, the control system which bites being a Wayside to Train communication for immediacy, it is a system of the Vital concept the immediacy of the citizen Data evil the radio information transmission and the train of the interface which is accurate from unmanned operation and, will decipher, will accomplish it will guarantee. It respects the passenger accident prevention and an air question environment improvement from subway platform and phul leys the screen door of Platform(PSD) with the fire tube frost it refers and part it treats and to sleep it does, ODM which bites is accuracy and immediacy of altitude and when seeing from the viewpoint which demands the trust of altitude, ODM system the trust of car incest interface in the equipment construction which is safe and the comparative analysis back of the system analysis against the control which bites and case study and other subway system it leads from the research which it sees and signal - train in base grudge to sleep it contributes it does.

• Journal of Information Technology Services
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• v.9 no.2
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• pp.1-20
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• 2010

The IT convergence industry is expected to create some high added-value, yet the IT convergence service is still in its introductory stage, which requires the utilization of yet to be tried future technologies and development methodologies that have been never tried in the past; therefore, there is certain risk involved regarding the success of development during the introduction of service and the development of technology. From such perspective, this study found examples of the services in the IT convergence industries and the application technologies for the realization of those services; and conducted a research based on the examples, using the technical Characteristics classification; and based on the result, analyzed the standards and the peculiarity of technologies employed for the IT convergence service and the correlation and the complementarity between them; also identified the standards and the peculiarity of technologies required by the IT convergence services and analyzed the correlation between them; and finally analyzed the compatibility between the IT convergence services and the applied technologies. The conclusion of this study is expected to be utilized for selecting technologies for the introduction and the operation of the optimal IT convergence service and as a benchmark as well.

• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.277-282
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• 2009

A temperature equation which is derived from an enthalpy transport equation by using an assumption of a constant specific heat is very attractive for analyses of heat and fluid flows. It can be used for an analysis of a solid-fluid conjugate heat transfer, and it does not need a numerical method to find temperature from a temperature-enthalpy relation. But its application is limited because of the assumption. A new method is derived in this study, which is a temperature-explicit formulation of the energy equation. The enthalpy form of the energy equation is used in the method. But the final discrete form of the equation is expressed with temperature. It can be used for a solid-fluid conjugate heat transfer and multiphase flows. It is found by numerical tests that it is very efficient and as accurate as the standard enthalpy formulation.

• Journal of Institute of Convergence Technology
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• v.3 no.1
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• pp.19-23
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• 2013

This study is concerned with air-conditioning system in use of thermoelectric device. It is introduced that the well designed structures for better cooling & heating performance with high efficiency. And also it is performed that the system performance test of four types trial products for the use of hybrid commercial vehicle. System performance is affected by many component parts, especially heat sink design & power control method. It is applied that dual extrusive fin tube with buffer zone for the effective radiating of circulating liquid in tube. And also it is applied that power supply method with constant-current system. It is attained that system cooling capacity is 1.2kW, COP is 0.95.

• Journal of Acupuncture Research
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• v.20 no.2
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• pp.1-10
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• 2003

Objective : It is limited to verify existence and a part of characteristic of MS(Meridian system) in modern MS hypothesis. Because it is that an object of scientific approach is to prove a structure of MS. Then according to DMMS, we will research on a subject of MSs rules. This is a paper on the investigation of DMMS in aspects of propriety and supplement. Results : DMMS is composed of organizational anatomy system, MS, signal system. This means that the contents of classic MS theory divide into three dimensions. It includes classic MS theory and explains modern MS hypothesis with DMMS. But is has two problems that one is the difference between the right side and the left in the same meridian and the other is a lack of dynamic idea(動態觀念). After apply this ti analysis system, it will be reasonable to DMMS. It indicates to use various ways of a science, especially, mathematics, system theory, information theory, control theory to supplement the DMMS. Conclusions : Although the scientific study of MS is stagnant, the approach of this DMMS will provide us with a new result of MS.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.55
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• pp.107-116
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• 2000

Electronic Commerce is purchasing or sales a products and services to customers using computer network. It is different to traditional commerce. Also, It divide into business to business commerce and business to customer commerce. Cyber Shopping Mall is a representative type of business to customer commerce. The interest and demand of national business to customer commerce is explosively increasing with industry. It expect to reach 61 billion won in the 2000. Thus Structure of Cyber Shopping Mall is the more complex and the more vary types. It is the problem that change of established Cyber Shopping Mall structure is very difficult. The purpose of this study Is designed to Cyber Shopping Mall Purchase Process that deal with quickly changable internet environment and meet the needs of customers immediately using UML(Unified Modeling Language) in design phase determinant of Cyber Shopping Mal1 structure. Cyber Shopping Mall Purchase Process is designed to have objective-oriented development methodology's advantage. It has a flexibility in case of shopping mall structure change and acts as useful guideline in design phase of construction of Cyber Shopping Mall.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1747-1755
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• 2008

Design of the reinforced roadbed thickness is concerned with safe operation of trains at specified levels of speed, axle load and tonnage. There are two methods for evaluating it. One is using an experimental equation and the other is using elastic theory with considering axle load, material properties of subsoils and allowable elastic settlement. Multi-layered theory is used to determine reinforced roadbed thickness by RTRI. Although their reinforced roadbed thickness is designed with an objective of achieving a minimum standard 2.5mm of settlement on the subgrade surface, it is hardly applied to real design. Li(1994) has suggested the experimental model which design approach is to limit plastic strain and deformations for the design period. It is worth due to adopting soil equivalent number of repeated load application. Moreover, it has been a more advanced method than existing design methods because including resilient modulus of subsoil beneath track, soil deviator stress caused by train axle loads and MGT. In this paper, it is analyzed under domestic track conditions to estimate the reinforced roadbed thickness with different soil types.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1566-1574
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• 2004

This study tried to find out alternatives adjusting basic fare using customer survey. But it merely verified that train fare decision is made by government's role and market status. Also, it has a limitation deciding resonable fare of KTX that average cost and marginal cost calculation is impossible because Korean National Railroad does not follow 'Activity Based Costing'. It is rational fare decision that performing survey to railroad experts and general customers, and compare two results. Summarizing results of this study, 1. The hypothesis 'Experts' perceived fare level of KTX is higher than that of general customer. 'is carried. It suggests that following experts' opinion with general customer's is very rational method to decide fare level. 2. The hypothesis 'Experts expect lower level of fare discount rate than general customer.' is carried. 3. It is hard to decide priority among many kinds of discount for difference of two group's preference. However, following recent research project is maximized by discounting fare 30$\%$ on 40$\%$ of total passenger and expand number of discount kinds step by step are desirable.