• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.50.5-50
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• 2002

In this paper, we propose a method using neural network (NN) to improve the motion control of a decentralized control system for cooperative transportation. In our former work, a decentralized control system for transporting a single object by multiple nonholonomic mobile robots has been developed. One of these mobile robots acts as a leader, who is assumed to be able to plan and to manipulate the omnidirectional motion of the object. Other robots, referred to as followers, cooperatively transport the object by keeping a constant position relative to the object. in this work, it is assumed that the leader can not only plan but also broadcast the local velocity of the object. Then...

• 한국ITS학회:학술대회논문집
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• 한국ITS학회 2004년도 제3회 정기총회 및 추계학술대회
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• pp.282-287
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• 2004

• 방송공학회논문지
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• 제8권3호
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• pp.259-267
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• 2003

본 논문에서는 이동 멀티미디어 방송 환경에서 대화형 서비스를 제공하기 위한 이동 멀티미디어 방송 미디어 처리기를 제안한다. 제안한 미디어 처리기는 오디오/비디오 부호화기로 MPEG-4 AVC(Advanced Video Coding) 및 MPEG-4 BSAC(Bit Sliced Arithmetic Coding) 부호화기를 사용하여, MPEG-4 IOD(Initial Object Descriptor)/OD(Object Descriptor)/BIFS(Binary Format for Scene) 데이터를 생성하는 기능, MPEG-4 AVC/BSAC 및 생성된 MPEG-4 OD/BIFS 데이터를 SL(Sync Layer) 패킷으로 캡슐화하는 기능, SL 패킷을 MPEG-2 TS(Transport Stream)로 패킷화하는 기능 및 다중화하는 기능을 지원할 수 있도록 설계하였다. 본 논문에서 제안한 이동 멀티미디어 방송 미디어 처리기는 사용자에게 MPEG-4 시스템 규격을 기반으로 대화형 서비스를 지원할 수 있다.

• 한국측량학회지
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• 제39권6호
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• pp.515-523
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• 2021

지하공간 통합지도는 지하시설물, 지하구조물, 지반정보로 구성되어 있으며, 주기적으로 갱신이 발생하고 있다. 본 논문에서는 통합지도 갱신 속도를 단축하기 위해 변화된 지반정보만을 탐지 및 추출하는 시스템을 설계하고 이를 구현하였다. 변화 객체를 찾아내기 위해 신규 입력된 지도와 통합지도에 저장된 참조 지도에 포함된 모든 객체들을 비교하였다. 객체를 비교하여 결과를 생성하는 전체 과정을 기능별로 분류하였으므로, 구현된 시스템은 객체 비교기, 변화 객체 탐지기, 과거 데이터 관리기, 변화 객체 추출기, 변화 유형 분류기, 변화 객체 저장기 등의 모듈로 구성되었다. 구현된 시스템의 성능을 평가하는 지표로 변화 객체 탐지율 및 추출률을 사용한다. 개발된 컴포넌트를 평택시 시추공, 관정, 지층, 암상 등에 적용한 결과 각 레이어의 신규, 삭제, 변경(속성) 객체들을 각각 100% 탐지하였다. 또한, 지도를 비교할 때마다 참조 지도를 다운로드 받음으로써 참조 지도의 최신성이 보장되는 장점을 제공하였다. 추후, 현업에 적용하기 위해 다양한 데이터를 사용하여 개발된 결과의 안정성과 효율성을 확인하는 연구가 필요하다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.792-796
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• 2006

In recent years, the semiconductor industry and the optical industry is developed rapidly. The recent demand has expanded for optical components such as a optical lens, a optical semiconductor and a measuring instrument. Object transport systems are driven typically by the magnetic field and the conveyer belt. Recent industry requires more faster and efficient transport system. However, conventional transport systems are not adequate for transportation of optical elements and semiconductors. Because conveyor belts can damage precision optical elements by the contact force and magnetic systems can destroy the inner structure of semiconductor by the magnetic field. In this paper, the levitation transport system using ultrasonic wave is developed for transporting precision elements without damages. This transport system is using 2-mode ultrasonic wave excitation and flexural beam modes shapes are evaluated. It compared simulation results with experimental results

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.81-82
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• 2006

Conveyor-type transporters have been widely used as a typical delivery system of semi-conductor, FPD and other IT-related products. However, as the IT-product is getting larger in size and higher in resolution, several problems are caused by mechanical contacts between the transporter and target object. In this context, recently, lots of efforts are being devoted for development of various contact-free handling systems to get rid of deffets and oil contaminations. The objectives of this paper are to characterize suspension mechanisms and to investigate air flow effects on air levitation transport system. For this purpose, a series of CFD analyses were carried out and the simulation data showed a good agreement with the corresponding experimental ones. It is anticipated that the promising result can be used as a basis for concept design of the transport system.

• 전기전자학회논문지
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• 제17권2호
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• pp.159-162
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• 2013

본 논문에서는 SOAP(Simple Object Access Protocol)에 대하여 JAVA와 .NET 두 가지 플랫폼에 따른 성능 분석을 수행한다. SOAP는 다양한 전송 계층 프로토콜을 이용할 수 있는데, 본 논문에서는 HTTP, TCP, UDP를 이용하여 성능 분석 방법을 제안하고 제안한 방법을 토대로 성능 분석을 실시하였다. 성능 분석 결과는 시스템 환경 및 네트워크 부하 정도에 따라 다르게 도출될 수 있다. 따라서 정확한 성능 분석을 위해 동일한 환경을 구축하여 진행하였다.

• 유통과학연구
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• 제13권10호
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• pp.123-133
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• 2015

Purpose - The Korean government has devised intermodal transportation policies and granted subsidies to shippers and logistics companies that made a conversion of transportation means through the policies. This provides support by expanding the complex uniform railroad transportation and overhauling the deteriorated railroad facilities. As for 2013, however, the freight transportation percentage of railroad was 4.5% in tons and 8.5% in ton kilometers. Meanwhile, since the 1990s, developed countries such as the U.S. and Europe have been trying to expand intermodal freight transport with a legal and institutional support to build a logistics system corresponding with social and economic environmental changes. In this study, I set out to examine the effects of the intermodal freight transport policies in the EU and the U.S., and to explore the direction of setting up a rail intermodal transport system in South Korea. Research design, data, and methodology - The paper used a qualitative research methodology through the literature review. First, was an overview of Intermodal transportation in the EU, U.S. and UN. Second, it describes the development of transport in Europe and the U.S. with particular emphasis on intermodal freight transport. Third, it explores the direction of setting up a intermodal freight transport in South Korea. The last section contains concluding remarks. Results - As for the EU, it has been promoting integration between transport and intermodal logistics network designs while utilizing ITS or ICT and supports for rail freight intermodal by giving reduction to a facilities fee or subsidizing for rail freight in order to minimize the cost of external due to freight transport. On the other hand, as for the U.S., it has been made up of an industrial-led operating project and has been promoting it to improve accessibility between intermodal hubs and cargo terminals through intermodal corridor program, and an intermodal cargo hub access corridor projects, etc. Moreover, it has tried to construct intermodal transport system using ITS or ICT and to remove Barrier. As a result, in these countries, the proportion of intermodal freight transport is going to be the second significant transport compared with rail and maritime transport. An Effective rail intermodal transport system is needed in South Korea, as seen in the case of these countries. In order to achieve this object, the following points are required to establish radical infrastructure policy; diversify investment financing measures taken under public-private partnerships, legal responsibilities, improvement of utilization of existing facilities to connect the railway terminal and truck terminal, and enhancement service competitiveness through providing cargo tracking and security information that combines the ITS and ICT. Conclusions - This study will be used as a basis for policy and support for intermodal freight transport in South Korea. In the future, it is also necessary to examine from the perspective of the shipper companies using the rail intermodal transport, ie, recognition of shipper, needed institutional supports, and transportation demand forecasting and cost-effective analysis of the railway infrastructure systems improvement.

• 정보교육학회논문지
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• 제2권1호
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• pp.130-137
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• 1998

An agent is a computer program that acts autonomously on a computer system. A mobile agent is not bound to the system where it begins execution. It has an ability to transport itself from on e system in a network to another. Mobile agent system solve the network traffic problem. Moreover, the agent may utilize the object services of the destination agent system. In this study the mobile agent system is introduced to support security service.

• 한국ITS학회 논문지
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• 제21권3호
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• pp.83-95
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• 2022

본 논문은 자율주행 차량 적용을 위한 객체 검출과 거리 추정을 수행하는 시스템을 제안한다. 객체 검출은 최근 활발하게 사용되는 딥러닝 모델 YOLOv4의 특성을 이용해서 입력 이미지 비율에 맞춰 분할 grid를 조정하고 자체 데이터셋으로 전이학습된 네트워크로 수행한다. 검출된 객체까지의 거리는 bounding box와 homography를 이용해 추정한다. 실험 결과 제안하는 방법에서 전반적인 검출 성능 향상과 실시간에 가까운 처리 속도를 보였다. 기존 YOLOv4 대비 전체 mAP는 4.03% 증가했다. 도심로 주행시 빈출하는 보행자, 차량 및 공사장 고깔(cone), PE드럼(drum) 등의 객체 인식 정확도가 향상되었다. 처리 속도는 약 55 FPS이다. 거리 추정 오차는 X 좌표 평균 약 5.25m, Y 좌표 평균 0.97m으로 나타났다.