• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.455-458
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• 2002

Design methods are presented for an X-band traveling-wave slot array realized on a rectangular waveguide. An array of 21 longitudinal slots is realized on the broad wall of a rectangular waveguide. The squint of the antenna main beam is adjusted using the element spacing and the waveguide broad wall dimension. The excitation of the array is controlled by the slot offset from the waveguide center line Multiple I-plane steps are placed around last slot elements so that the second-order beam due to tile reflected wave Is minimized A waveguide-to-coaxial adapter Is designed for feeding the array antenna from a coaxial system. Results of the design show an outstanding performance of the antenna 17.1 dB gain. 36"beam 1111, and -21 dB maximum sidelobe level.evel.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.63-64
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• 2006

Recently, researches for high-speed optical devices have been increased to provide mass data transmission and high-speed optical communication. Optical modulator in the transmission link is one of the crucial devices in total optical network system and it can affect a great effect to the whole transmission properties. In this paper, traveling wave electro-absorption modulator (TWEAM) is examined to ensure high efficiency in the RF range and wide bandwidth. In addition, the temperature-dependence electrical characteristics of TWEAM is investigated. Temperature dependent property variations were characterized using I-V and C-V measurement.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.10a
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• pp.43-49
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• 1997

A rotating rigid disk, attached on a flexible shaft or supported by a torsional spring, experiences precessional whirling due to gyroscopic moment loading. It is well known in rotor dynamics area that, as the rotational speed increases, the precessional mode of the rotating rigid disk starts splitting into two: forward and backward precessional modes. On the other hand, it is also well known in disk vibration area that a rotating flexible disk also shows another kind of mode splitting phenomenon due to the rotation, resulting in forward and backward traveling waves. When rotating multiple flexible disks are coupled in vibration with the supporting Flexible shaft, the associated mode splitting should be compatible with the two seemingly different vibration analysis methods. This paper investigates the possibility of fusing the precessional and traveling wave mode splittings so that the bending coupled disk vibrations in HDD spindle systems can be better understood.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.151-154
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• 2005

Tilting train improves a traveling velocity through giving a tilt the car-body without ride comfort deterioration In curve. Dynamic behavior in deceleration will show quite another feature in constant velocity, In this study, we see through the dynamic behavior due to a variation of braking force in Korean Tilting Train. Hence we compose of 3D dynamic model, as well as we check upon the property in service braking condition and unique braking condition with a fault system. This study has the meaning with reference data of developing Korean Tilting Train test traveling.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.1107-1111
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• 2004

Tilting train improves a traveling velocity through giving a tilt the car-body without ride comfort deterioration in curve. Dynamic behavior in acceleration or deceleration will show quite another feature in constant velocity. In this study, we see through the dynamic behavior due to a variation of tractive force and braking force in Korean Tilting Train. Hence we compose of 3D dynamic model, as well as we check upon the property in service tractive condition and unique tractive condition with a fault motor. Besides we check upon the property in service braking condition and unique braking condition with a fault system. This study has the meaning with reference data of developing Korean Tilting Train test traveling.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.33
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• pp.29-37
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• 1995

An Automated Storage/Retrieval Systems(AS/RS) has been gradually emphasized because of the change of production and distribution environment. This paper develops algorithm and Shortest Distance Model that can reduce the traveling time of a stacker crane for efficient operation of AS/RS. In order to reduce the traveling time of a stacker crane, we determine the order processing and then the sequencing of storage/retrieval for each item. Order processing is determined based on the SPT(Shortest Processing Time) concept considering a criterion of retrieval coordinate. The sequencing of storage/retrieval is determined based on the Shortest Distance Model by using a modified SPP(Shortest Path Problem) of network problem. A numerical example is provided to illustrate the developed algorithm and Shortest Distance Model.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.8
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• pp.144-152
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• 2003

The purpose of this paper is to establish an effective inspection system by using OMM (On-Machine Measurement) system based PC-NC. This system can reduce manufacturing lead time because part is inspected each process. Inspection process planning is accomplished by determining the number of measuring points, their location, measuring path using fuzzy logic, Hammersley method, traveling salesperson problem. Inspection with contacted sensor improve quality as inspection feature is developed to based machining feature. This method is tested by simulation and experiment, then analyzed measuring data and geometry tolerance.

• Journal of Biosystems Engineering
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• v.17 no.1
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• pp.27-36
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• 1992

Computer simulation was carried out to predict the motion and overturns of power tiller-trailer system this system when traveing over an obstacle on inclined planes. To estimate the effects of design factors (mass center of main body and wheel base), ground factors (ground inclination and height of obstacle), and operation factors (traveling velocity) on the sideways overturn, the motion of power tiller-trailer system was simulated as the factors were varied with five different levels.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.279-282
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• 2002

This Paper of use vision system, there is no DGPS's information, DGPS data value receives real time exactly without being influenced in surroundings environment because using vision system that is used in self-regulation traveling by car system. Therefore, conversion and DGPS of received in camera coordinate changing coordinate error correct and wish to grasp correctly position of vehicles.

• Journal of Distribution Science
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• v.15 no.5
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• pp.53-64
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• 2017

Purpose - This study focuses on use intention of mobile travel Apps by Chinese tourists visiting Korea based on UTAUT model, ISS model and ITM model. And the corresponding market promotion schemes are proposed for operators of mobile travel Apps by the research results. Research design, data, and methodology - After collecting 326 respondents in China with cross-sectional questionnaires, this study begins the empirical research with users of mobile travel Apps, and analyzes data with IBM SPSS 23.0 and IBM AMOS 23.0. Results - The results of this study include the following aspects: firstly, the System quality and Information quality are accepted for hypotheses of Satisfaction and Performance expectancy. Secondly, the Personal Propensity to Trust and Firm Reputation are accepted for Initial Trust hypothesis, and the hypotheses of Firm Reputation and Initial Trust are accepted for Use Intention. Thirdly, the Performance expectancy, Effort expectancy, Social influence are accepted for Use Intention hypothesis. Conclusions - With the increase of tourists visiting Korea, it can be predicted that the needs visiting Korea will be increased persistently for Chinese - this trend brings about the increase of the Chinese travel. First, information quality greatly influences satisfaction and performance expectancy. The research result shows that, the higher the mobile traveling App's information quality is, the higher the satisfaction and performance expectancy will be. Therefore, operators of mobile traveling App should have in-depth investigations towards users, to know the latter's real demand to the information quality and then provide corresponding services. Second, performance expectancy and effort expectancy greatly influence users' intention. Therefore, mobile traveling App operators should improve Apps' convenience and efficiency and, in doing so, find an effective method for market expansion. Third, social influence greatly affects users' intention. The result shows that mobile traveling App operators should pay attention to the influence of mass media and friends' recommendation on users, thereby it is necessary to improve advertisement activities. Fourth, initial trust also influences users' intention. The result shows that initial trust is a key element inducing users to generate use intention. Therefore, mobile traveling Apps operators should make efforts to catch elements that influence users' initial trust.