• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.2
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• pp.60-67
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• 2017

A baggage handling system (BHS) in airport is an unified system for moving the passengers' baggage in designated time. Input baggage from the check-in counter travels to the baggage claim area or cargo handling terminal through this system. In particular, entryway BHS consists of conveyors, X-ray and sorters such as tilt-tray to send the baggage to departing airplane and it could have various problems for handling certain amount of baggage in restricted time such as baggage jamming at certain merge point. This causes systemic error such as delay of the time, omissions of the baggage and even breakdown of the equipment and inefficiency. Also the increasing maximum time of the baggage passing through the BHS could delay the flight schedule and finally decrease the service level. Thus, the algorithm for controlling the flow of the merge is essential to the system. The window reservation algorithm is the one of the most frequently used methods to control the merge configuration. Above all, the reserve location, so called reserve ahead point, that allocates the window is important for the performance of the algorithm. We propose the modified window reservation algorithm and the best reserve locations by changing the reserve ahead point in the induction conveyors. The effect of various reserve ahead points such as the capacity and utility of the system were analyzed and the most effective reserve ahead point combination was found. The total baggage processing time and the utilization of the tilt-tray are properly considered when choosing the optimal Reserve ahead point combination. In the layout of this study, the configuration of four conveyors merged into one tilt-tray is studied and simulation analysis is done by AutoMod(R), 3D simulation software. Through the simulation, the window reservation algorithm is effectively operated with the best combination of reserve ahead point which reduces the maximum baggage travel time.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1229-1234
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• 2009

The rolling stocks of KORAIL are KTX, Saemaulho Multiple Unit(PP), New Electrical Locomotive(DL), Electrical Locomotive(EL), Diesel Locomotive, Metropolitan Commuter Train(CDC), VVVF and Resistance Controlled Multiple Unit, etc. EMU with the maximum speed of 150km/h is under the test run at the moment. Electrical Multiple Units for mainlines with 180km/h speed are supposed to be introduced as a substitute for Saemaulho Multiple Unit which is scheduled to be out of service. But the specification standard for the control board design of train driver's cab does not exist and there is no a study for layout and type of controlling device with driver's ergonomical approach. That's why the types of controller and operating are different from rolling stocks, which has high possibility of driver's human error and needs education whenever a new car comes in. Based on the opinion poll of drivers, design specification of safety engineering and ergonomics for controlling devices and safety facilities can improve exact control for devices and deal quickly with an emergency so as to improve rolling stock safety and operational efficiency.

• Journal of the Korea Society for Simulation
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• v.20 no.2
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• pp.67-76
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• 2011

Order picking in automotive service parts warehouses is considered to be the most labor-intensive operation. Such warehouses contain hundreds of thousands of items, but normally 20% of products contribute to about 80% of turnover according to Pareto's 80-20 principle. Therefore most fast moving items are located near an outbound area which is called the "Golden Zone". Order picking routing efficiency is related to productivity and labor cost. However, most companies use simple methods. In this paper, we describe a series of computational experiments over a set of test cases where, we compared various previously existing routing heuristics to an optimal algorithm. We focus on examining the influence of the golden zone on the performance and selection of routing methods. The results obtained show that the optimal routing method increases the productivity at least 17.2%, and all the routing methods have better performance as the pick up rate from the golden zone increases.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.2
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• pp.199-207
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• 2011

A Ku-band low noise amplifier has been designed and fabricated by using 0.25 um SiGe BiCMOS process. The developed Ku-band LNA RFIC which has been designed with hetero-junction bipolar transistor(HBT) in the BiCMOS process have noise figure about 2.0 dB and linear gain over 19 dB in the frequency range from 9 GHz to 14 GHz. Optimization technique for p-tap value and electro-magnetic(EM) simulation technique had been used to overcome the inaccuracy in the PDK provided from the foundry service company and to supply the insufficient inductor library. The finally fabricated low noise amplifier of two fabrication runs has been implemented with the size of $0.65\;mm{\times}0.55\;mm$. The pure amplifier circuit layout with the reduced size of $0.4\;mm{\times}0.4\;mm$ without the input and output RF pads and DC bais pads has been incorporated as low noise amplication stages in the multi-function RFIC for the active phased array antenna of Ku-band satellite VSAT.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.3
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• pp.622-629
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• 2004

Recently, as digital broadcasting and internet are spreaded out of the world, we can easily use informations with less restrictions of time and space. According to the current trends, concerns for the ways of representing multimedia data has been rapidly increased, and users demand the services with integrated document that takes not only simple text and image but also time varying audio-visual data. Therefore, in 1998, W3C presented an international standard, SMIL in order to solve multimedia object representation and synchronization problems. By using SMIL, various multimedia elements can be integrated as a multimedia document with proper view in a space and time. Using this SMIL document, we can create new internet radio broadcasting service that delivers not only audio data but also various text, image and video. In this paper, we describe on a SMIL document editor for the common users to be able to represent time varying multimedia data with special layout and synchronization of time and space.

• Journal of The Korea Institute of Healthcare Architecture
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• v.23 no.4
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• pp.67-75
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• 2017

Purpose: This study is for the facility eligibility and improvement evaluation analysis for the patient care environment of 7 facilities which has national inpatient isolation units. Methods: For the evaluation, first of all, the patient care environment of national inpatient isolation units are scrutinized by the checklist which is used on from 2014 with the 4 fields of criteria : architectural planning and layout, general requirement and condition for operating the negative pressured isolated patient room, HVAC system, and waste water discharging system. Finally, the evaluation results are compared with that of 2014. Results: The result shows that the average value of facility eligibility is 89.3 percent and which is 8.9 percent higher than the value before the MERS occurred. Implications: It is clear that facility remodeling of 7 institutions is being performed continuously, and the result of facility eligibility evaluation is reflected on design of a new 21 national inpatient isolation units those are going to be constructed from 2016. Therefore, it is expected that this study is used as a practical reference to establish the criteria of patient care environment management and safety management for both infectious disease outbreak and general service condition.

• Steel and Composite Structures
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• v.32 no.1
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• pp.1-19
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• 2019

The aim of the paper is the prediction of the seismic collapse mode of steel storage pallet racks under seismic loads. The attention paid by the researchers on the behaviour of the industrial steel storage pallets racks is increased over the years thanks to their high dead-to-live load ratio. In fact, these structures, generally made by cold-formed thin-walled profiles, present very low structural costs but can support large and expensive loads. The paper presents a prediction of the seismic collapse modes of multi-storey racks. The analysis of the possible collapse modes has been made by an approach based on the kinematic theorem of plastic collapse extended to the second order effects by means of the concept of collapse mechanism equilibrium curve. In this way, the dissipative behaviour of racks is determined with a simpler method than the pushover analysis. Parametric analyses have been performed on 24 racks, differing for the geometric layout and cross-section of the components, designed in according to the EN16618 and EN15512 requirements. The obtained results have highlighted that, in all the considered cases, the global collapse mechanism, that is the safest one, never develops, leading to a dangerous situation that must be avoided to preserve the structure during a seismic event. Although the studied racks follow all the codes prescriptions, the development of a dissipative collapse mechanism is not achieved. In addition, also the variability of load distribution has been considered, reflecting the different pallet positions assumed during the in-service life of the racks, to point out its influence on the collapse mechanism. The information carried out from the paper can be very useful for designers and manufacturers because it allows to better understand the racks behaviour in seismic load condition.

• Journal of the Korea Convergence Society
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• v.13 no.2
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• pp.143-150
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• 2022

Audio-based SNS also needs a visual guide to reach the contents desired by the users. Therefore, this study investigates visual interface design elements that influence the experience of using audio contents in audio-based SNS. Prior researches have identified that the generally acknowledged interface design elements are important for the usability of audio contents. Through the analysis of the currently launched audio-based SNS, the influence of general interface elements were again confirmed, and via the analysis of other audio content services, a new interface evaluation element was explored. Accordingly, with five general interface evaluation elements-layout, color, icon, typography, graphic image, multimedia elements are newly defined and proposed as crucial factors in evaluating the UI of audio-based SNS.

• Land and Housing Review
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• v.14 no.2
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• pp.97-107
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• 2023

This study examined how to better provide quality temporary housing for people in the event of natural and social disasters. Design for Manufacture and Assembly (DfMA) is suitable for creating an efficient planning model for the mass production and transport of a modular house. The proposed DfMA model has the following three characteristics. First is the division of the modular house into service modules and functional modules and to create diversity by developing standard parts and multi-functional parts. Second is a flexible layout suitable for various site conditions. Such flexible layouts would allow identical homes to be mass produced and deployed to a variety of locations, both nationally and internationally. Third is to simplify and minimize the automation process with dry construction to increase production efficiency. Application of this DfMA design method can lead to reduced construction time and cost and improve housing quality.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6A
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• pp.417-424
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• 2011

This study focused on development of 60 m span PSC girder considering not only structural performance, but also economical efficiency and constructability including from the improvement of cross-section to the tendon profiles in sequence. Bulb-T type cross section was derived from optimization and actual possibilities to design a bridge were assessed through cross section evaluation. Tendons were also arranged efficiently so that the girder could resist the service load effectively. After developed girder was applied to a sample bridge, result of finite element analysis proved all load steps were satisfied with the allowable stress. Furthermore, it seemed that sufficient redundancy will be available to design a bridge safely. Based on these, a full-scale 60 m span girder was fabricated and 4 point bending test was performed. An initial crack occurred over twice of the service load in this experiment, which establishes adequate structural performance. 60 m span Half-Decked PSC girder developed in this study has a lower height for the given span which resulted from cross section improvement and efficient tendon layout. This girder also has not only the structural advantage, but also advantages in economical efficiency and constructability.