• 경영과학
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• 제29권2호
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• pp.79-90
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• 2012

Focusing on the rapid market penetration of smart phones, the importance of LBS (Location Based Service) is drastically increased. However, traditional GPS method has critical weakness caused by limited availability, such as indoor environment. WPS is newly attractive method as a widely applicable positioning method. In WPS, RSSI (Received Signal Strength Indication) data of all Wi-Fi APs (Access Point) are measured and stored into a huge database. The stored RSSI data in database make single radio fingerprint map. By the radio fingerprint map, we can estimate the actual position of target point. The essential factor of radio fingerprint database is data integrity of RSSI. Because of millions of APs in urban area, RSSI measurement data are seriously contaminated. Therefore, we present the unified filtering method for RSSI measurement data. As the results of filtering, we can show the effectiveness of suggested method in practical positioning system of mobile operator.

• 한국지리정보학회지
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• 제9권2호
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• pp.30-41
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• 2006

이 논문은 효율적인 차량 이동 궤적 관리를 지원하는 e-logistics 시스템을 제안한다. 최근의 무선통신의 발전은 물류 차량의 추적, 휴대폰 사용자 위치 서비스, 위치기반 상거래를 포함한 위치기반서비스들이 등장하게 하였다. 물류 시스템은 물류 센터에서 차량과 배송품의 위치를 계속적으로 파악해야 하므로 차량 추적을 필수적으로 수반하게 된다. 좀 더 나아가서, 계속적으로 이동하는 차량과 배송품의 위치 궤적을 저장하고 관리하는 것은 효율적인 물류 계획과 배송을 지원하기 위해 필수 불가결한 요소이다. 제안된 시스템은 실세계 모바일 환경에서 물류 배송 정보의 효과적인 관리뿐만 아니라, 기존의 공간 데이터베이스가 갖는 공간객체 관리 기능을 포함한다. 또한 효과적인 물류 이동 경로 관리 및 검색을 수행하기 위하여 기존의 TB 트리의 데이터 갱신 성능을 개선하고, 다중버전 기법을 도입한 색인을 사용하였다. 제안된 시스템은 소포관제와 유사한 차량 추적 시스템, 위치기반서비스 등과 같이 실시간 모바일 환경에서 연속적으로 위치를 변경하는 이동객체 관련 분야에 적용 가능하다.

• 디지털산업정보학회논문지
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• 제12권1호
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• pp.63-69
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• 2016

Although the previous information technologies had been used for the quick and accurate processing of work, At present, however, as the combination with the Internet, the IOT(Internet-of-Things) era in which the diverse pieces of information are collected and handled through the sensor networks is in progress. Among these application fields of the IoT, the indoors position identification technology has been developing in the direction of providing the position information in the buildings of which the lengths and the interiors are complicated and in the direction of providing the various pieces of information and others of the like to the nearby customers. In this paper, we proposed an indoors position identification system that detects the patrol positions of the prison officers in the correctional facilities and in the prisons by using the ultrasonic waves, that transmits these to the control system and the data gateway, and that transmits the detected data. The Indoors Positioning identification System is organized with the tags for recognizing the positions that transmit the ultrasonic signal, ultrasonic receiver and data gateway. And the indoors position information data were transmitted to the management system through the data gateway. We evaluated the transmission error, by changing the distance of the proposed system for location recognition tag and the receiver, As a result, we found out that, when the transmission distance was 10 cm or less, the errors occurred in the form of the distortions. And when it was 110 cm or more, the transmission errors occurred due to the propagation diminutions of the ultrasonic wave signals. And when the transmission distance was from 10 cm to 100 cm, it was shown that the proposed system was possible without any errors.

• 산업경영시스템학회지
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• 제21권45호
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• pp.33-45
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• 1998

The typical characteristic of PDM(Product Data Management) System seperates the databases to store the meta data and applications. Therefore, meta data contains the information for the location of file, user profiles, relationships between the files, and process. PDM utilizes these information efficiently and does file management, configuration management, and process management. In this view, the integration strategy of PDM is to merge data and process. In the view of architecture, the interface between data and application and the actions of each application execute seamlessly. This architecture is viewed as integrated data and process among enterprises and implemented with client/server technology in distributed process environment that interfaced with open object-oriented technology which is developed with business object in the object-oriented infrastructure. In this paper, we studied the definition, function, and scope of PDM and researched the core technologies to implement the PDM integration environment. We also researched the PDM utilization in distributed enterprise environment and implementation of PDM integration environment with this technical background.

• 한국지리정보학회지
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• 제8권2호
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• pp.55-67
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• 2005

본 연구에서는 계층분석과정에 대한 노선 선정에 요구되는 자료들을 추출 및 이용하여 합리적인 노선 선정의 방법을 제시하였다. 선정된 노선의 결과를 GIS를 이용하여 시각화 및 분석하였으며, 종단선형을 고려한 선형 프로그램을 개발 및 구축하였다. 이러한 연구를 요약하면 GIS 기반의 계층분석과정을 응용하여 생성된 노선을 기준으로 기존 노선의 적정성에 대한 평가를 정량적으로 할 수 있었으며, 신설될 노선에 적용하면 도로 계획 및 기본 설계에 객관적이고 신뢰성 있는 노선의 평가를 할 수 있었다. 기존의 2차원적 정보에 의한 의사결정시스템에서 종단계획까지 고려한 3차원 정보에 의한 의사결정시스템을 적용함으로서 노선 선정기법을 향상시켰고 종단경사, 토공량, 구조물 규모와 위치, 공사비 등의 정보를 독립 변수로 할 수 있으므로 더욱 과학적이고 합리적으로 도로 설계를 할 수 있었다.

• 한국멀티미디어학회논문지
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• 제5권3호
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• pp.316-322
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• 2002

본 논문에서는 파일 데이터의 실시간 재생 서비스를 제공하기 위한 UNIX파일 시스템의 연속 블록 할당에 대하여 다루고 있다. 설계된 블록 할당 방식은 사용자가 저장 데이터와 함께 지정한 소비 전송율을 지원할 수 있도록 적절한 디스크 위치에 데이터를 배치하여 실시간 재생 서비스를 지원할 수 있도록 하고 있다. 이를 위하여 데이터 전송율에 영향을 미치는 요소 중에서 가변적인 특성인 연속 블록 수와 저장 데이터들의 실린더 간격과의 관계를 분석하여 특정 실린더 간격 별로 연속 블록을 저장하는 방식을 채택하였다. UNIX시스템의 블록 할당 방식은 임의의 실린더 위치에서 연속 블록을 찾는 것이 비효율적 이기 때문에 새로운 형태의 비트맵 방식의 유휴 블록 기법을 사용하였다. 비트맵 방식의 블록 관리 기법은 파일 시스템 블록들을 비트 단위로 사용/비사용 여부를 표시하여 임의의 실린더 위치에 존재하는 블록이 사용 가능한지를 효율적으로 검색할 수 있도록 하였다.

• 한국정보통신학회논문지
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• 제13권9호
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• pp.1865-1872
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• 2009

본 논문은 레거시를 통합 검색하기 위한 방안으로 XMDR을 확장하는 방안을 제안한다. 이러한 확장은 메타데이터의 관리를 위한 메타 시멘틱 온톨로지, 위치 정보를 위한 메타 로케이션, 그리고 시멘틱 웹을 표현하기 위한 표준 언어인 토픽맵을 결합한다. 본 논문에서는 이것을 TMDR(Topic Map MetaData Registry)이라 한다. 토픽맵은 지식계층으로 인덱스와 같은 역할을 수행한다. 그러나 토픽맵은 데이터의 변화가 빈번한 경우에는 효율이 떨어질 수 있다. 이러한 문제를 해결하기 위해 본 시스템은 메타 데이터 사이의 관계, 실제 데이터 사이의 관계 그리고 메타데이터와 실제 데이터 사이의 관계를 토픽맵으로 표현한다. 표현된 토픽맵은 메타 데이터 간의 관계로 인해 실제 데이터간의 관계 변화를 줄이는 방안을 제시한다.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.869-875
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• 2009

Safety is a big issue in the construction sites. For safe and secure management, tracking locations of construction resources such as labors, materials, machineries, vehicles and so on is important. The materials, machineries and vehicles could be controlled by computer, whereas the movement of labors does not have fixed pattern. So, the location and movement of labors need to be monitored continuously for safety. In general, Global Positioning System(GPS) is an opt solution to obtain the location information in outside environments. But it cannot be used for indoor locations as it requires a clear Line-Of-Sight(LOS) to satellites Therefore, indoor location monitoring system could be a convenient alternative for environments such as tunnel and indoor building construction sites. This paper presents a case study to investigate feasibility of Wi-Fi based indoor location monitoring system in construction site. The system is developed by using fingerprint map of gathering Received Signal Strength Indication(RSSI) from each Access Point(AP). The signal information is gathered by Radio Frequency Identification (RFID) tags, which are attached on a helmet of labors to track their locations, and is sent to server computer. Experiments were conducted in a shield tunnel construction site at Guangzhou, China. This study consists of three phases as follows: First, we have a tracking test in entrance area of tunnel construction site. This experiment was performed to find the effective geometry of APs installation. The geometry of APs installation was changed for finding effective locations, and the experiment was performed using one and more tags. Second, APs were separated into two groups, and they were connected with LAN cable in tunnel construction site. The purpose of this experiment was to check the validity of group separating strategy. One group was installed around the entrance and the other one was installed inside the tunnel. Finally, we installed the system inner area of tunnel, boring machine area, and checked the performance with varying conditions (the presence of obstacles such as train, worker, and so on). Accuracy of this study was calculated from the data, which was collected at some known points. Experimental results showed that WiFi-based indoor location system has a level of accuracy of a few meters in tunnel construction site. From the results, it is inferred that the location tracking system can track the approximate location of labors in the construction site. It is able to alert the labors when they are closer to dangerous zones like poisonous region or cave-in..

• 대한안전경영과학회지
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• 제12권4호
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• pp.169-174
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• 2010

EPCIS(EPC Information Services) system is a core component of EPCglobal Architecture Framework offering information of the freights, the time of awareness and the location of awareness on the EPCglobal Network. The role of EPCIS is to exchange information based on EPC. There are four kinds of event data which are object event data, aggregation event data, quantity event data, and transaction event data. These EPCIS events data are stored and managed in EPCIS repository. This paper deals with the method which diversifies the data flow load of intensive EPCIS events and effectively manages EPCIS repository for exchanging data smoothly. In order to verify a effectiveness, we measure the performance of the system using a simulation by comparing the existing method with the suggested method.

• 한국컴퓨터정보학회논문지
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• 제21권6호
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• pp.71-76
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• 2016

In this paper, we propose the mobile visual inspection information system using DGPS and portable range finder for levee safety inspection. Instead of existing visual inspection management method that is stored hand-written data, this system is designed to manage directly the visual inspection information using mobile devices in the field of levee. And through extracting accurate DGPS coordinates information about damage location of levee, this system is developed to ensure efficiency for the main task arising from the levee site such as inspection, maintenance and reinforcement. Furthermore, when damage has occurred at the point that inspector is not able to approach, this system can record the damage site data correctly, by converting data such as position, orientation and height of the damage point into the World Geodetic System coordinates. The position, orientation and height data was extracted automatically through the DGPS and portable range finder. And by applying the augmented reality method, this system was implemented for inspector to revisit the point of damage easily in order to perform the management, maintenance and reinforcement of the levee later.