• 한국산학기술학회논문지
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• 제18권5호
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• pp.99-110
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• 2017

레이다를 이용한 다수 표적의 상태 추정을 통해 추적 성능을 향상시키는 문제는 중요하다. 클러터 환경에서 추적 필터를 이용하여 다수 표적 추적 시 트랙과 측정치 간의 결합사건이 발생하며 개수가 증가함에 따라 결합사건은 기하급수적으로 증가한다. 이러한 환경에서 다수 표적 추적 필터 설계 시 고려해야할 문제는 첫째, 신속한 거짓트랙 제거 및 표적트랙 확정을 통하여 오경보율 최소화하고, 이를 통해 FTD(False Track Discrimination) 성능을 높인다. 둘째, 다수의 트랙이 측정치를 공유하는 결합사건 발생시 효율적으로 각각의 측정치를 트랙에 할당함으로써 트랙 유지성능을 향상시키는 것이다. 두 가지 고려사항을 통해 단일 표적 추적 자료결합 기법을 다수 표적 추적 필터로 확장하여 사용하며, 대표적인 알고리듬으로 JIPDAF(Joint Integrated Probabilistic Data Association Filter)와 LM-IPDAF(Linear Multi-target IPDAF)가 있다. 본 논문에서는 측정치 할당 시 생기는 수 많은 가설들에 대한 확률적 평가를 하지 않음으로써 측정치와 트랙의 개수에 따라 비선형으로 연산량이 증가하지 않으며, 클러터밀도 추정을 통해 트랙을 쇄신하는 트랙존재확률 기반의 LM-IPDAF 알고리듬을 소개한다. 그리고 LM-IPDAF의 트랙존재확률 산출 시 필요한 클러터밀도 추정 방법을 개선함으로써 연산량을 효과적으로 감소시킬 수 있는 방법을 제안하고 시뮬레이션을 통해 기존의 알고리듬과 비교, 분석하여 성능을 검증하였다. 그 결과, 위치 RMSE, Confirmed True Track 측면에서는 동일한 성능을 내면서 시뮬레이션 처리 시간을 약 20% 감소시킬 수 있었다.

• 한국인터넷방송통신학회논문지
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• 제23권6호
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• pp.185-190
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• 2023

최근 추적레이더는 다양한 환경에서 높은 해상도로 표적의 정보를 획득하기 위한 밀리미터파 추적레이더의 개발을 요구한다. 밀리미터파 추적레이더의 개발은 밀리미터파 추적레이더에 적용할 수 있는 송·수신 구성품의 개발과 동시에 추적레이더의 적용성을 필요로 한다. 개발된 송·수신 구성품의 적용성을 검증하기 위해서는 추적레이더의 운용개념을 적용한 송·수신 구성품을 제어하고, 상태를 확인할 수 있는 신호획득장치의 개발을 요구한다. 본 논문에서는 밀리미터파 추적레이더를 위해 개발된 구성품의 적용성을 확인할 수 있는 신호획득장치를 설계하였다. 구현한 신호획득장치는 수신신호를 검증하기 위해 4채널에서 입력되는 OOOMHz의 중심주파수와 OOOMHz 대역폭의 신호를 실시간으로 처리하기를 요구한다. 또한 추적레이더의 운용개념을 적용한 구성품 제어는 RS422, RS232, SPI 통신과 송수신구간 제어신호 생성으로 제어를 할 수 있도록 설계하였다. 마지막으로 신호획득장치 성능시험으로 구현한 신호획득장치를 검증하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.249-252
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• 2004

The automatic determination of vehicle operation status as well as continuous tracking of vehicle location with intelligent management is one of major elements to achieve the goals. Especially, vehicle operation status can only be analyzed in terms of expert experiences with real-time location data with scheduling information. However the scheduling information of individual vehicle is very difficult to be interpreted immediately because there are hundreds of thousand vehicles are run at the same time in the national wide range workplace. In this paper, we propose the location-based knowledge management system(LKMs) using the active trajectory analysis method with routing and scheduling information to cope with the problems. This system uses an inference technology with dispatching and geographic information to generate the logistics knowledge that can be furnished to the manager in the central vehicle monitoring and controlling center.

• 한국정보통신학회논문지
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• 제18권5호
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• pp.1171-1176
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• 2014

안구 추적은 눈동자의 움직임을 감지하여 안구의 운동 상태나 시선의 위치를 추적하는 인간과 컴퓨터의 상호작용(HCI)분야이다. 안구 추적은 사용자의 시선 추적을 이용한 마케팅 분석이나 의도 인식 등에 적용되고 있으며 다양한 적용을 위한 많은 연구가 진행되고 있다. 안구 추적을 수행하는 방법 중에 영상처리를 이용한 안구 추적 방법이 사용자에게는 편리하지만 조명의 변화와 스케일 변화 그리고 회전이나 가려짐에는 추적의 어려움이 있다. 본 논문에서는 이미지 기반의 안구 추적시 발생되는 조명, 회전, 스케일 변화 등 환경변화에도 강인하게 안구 추적을 수행하기 위하여 두 단계의 추적 방법을 제안한다. 우선 Haar분류기를 이용하여 얼굴과 안구 영역을 추출하고, 추출된 안구 영역으로부터 CAMShift과 템플릿 매칭을 이용하여 강인하게 안구를 추적하는 두 단계의 안구 추적 방법을 제안하였다. 제안한 알고리즘은 조명 변화, 회전, 스케일 등 변화하는 환경 조건하에서 실험을 통하여 강인성을 증명하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.353-356
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• 2005

In Taiwan, there are more the one hundred GPS tracking stations maintained by Ministry of the Interior (MOI), Academia Sinica, Central Weather Bureau and Central Geological Survey. In the further, they may be instead of the GPS controlling points after giving the lawful status. In other words, the engineers don't need to survey on the reference points when they are surveying in the field. They only need to download the GPS data via internet and process the observations in their company. The precise coordinates of the unknown points will be obtained. Therefore, the data qualities of the tracking stations are more and more important. In this study, six data quality indexes were adopted as follows: observations, cycle slips, multipath on L1, multipath on L2, clock offset and frequency stability. Besides, the relationships of the indexes and the positioning precision were found. The frequency stability of GPS receiver is the most important index, the cycle slip is the second index and the mutlipath is the third index. According to the results, the auto-analytical system of GPS data quality was established and the tracking stations were monitored. When the receiver got some problem or the station's environment changed, we hope to find and resolve the problems earlier to make sure the high data quality of the tracking stations. Moreover, we try to design a data quality verification to help users and let the engineers have more and more confidence when they use the data of GPS tracking stations.

• Journal of Welding and Joining
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• 제16권5호
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• pp.119-133
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• 1998

To implement full automation in pipe welding, it si most important to develop special sensors and their related systems which act like human operator when detecting irregular groove conditions. In this study, an automatic pipe Gas Metal Arc Welding (GMAW) system was proposed to full control pipe welding procedure with intelligent sensor systems. A five-axes manipulator was proposed for welding torch to automatically access to exact welding position when pipe size and welding angle were given. Pool status and torch position were measured by using a weld-pool image monitoring and processing technique in root-pass welding for weld seam tracking and weld pool control. To overcome the intensive arc light, pool image was captured at the instance of short circuit of welding power loop. Captured image was processed to determine weld pool shape. For weld seam tracking, the relative distance of a torch position from the pool center was calculated in the extracted pool shape to move torch just onto the groove center. To control penetration of root pas, gap was calculated in the extracted pool image, and then weld conditions were controlled for obtaining appropriate penetration. welding speed was determined with a fuzzy logic, and welding current and voltage were determined from a data base to correspond to the gap. For automatic fill-pass welding, the function of human operator of real time weld seam control can be substituted by a sensor system. In this study, an arc sensor system was proposed based on a fuzzy control logic. Using the proposed automatic system, root-pass welding of pipe which had gap variation was assured to be appropriately controlled in welding conditions and in torch position by showing sound welding result and good seam tracking capability. Fill-pass welding by the proposed system also showed very successful result by tracking along the offset welding line without any control of human operator.

• 한국멀티미디어학회논문지
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• 제24권1호
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• pp.146-154
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• 2021

Conspicuous consumption is often investigated in Korea and consumers purchase a product to publicly display economic power or social status. The existing studies argue that brand loyalty and luxury brand preferences escalate conspicuous consumption, and it is important to identify different visual perception to understand irrational consumers' behavior. Car emblem as brands' visual identity represents the brand's image, mission and message. Irrational consumers thus are expected have different visual perception to the emblem or logo. To understand the impact of irrational consumer behavior on visual perception, this study explored how brand loyalty and luxury brand preferences impact on the visual perception of car emblems between Korean domestic brand and imported brand. This study used eye tracking technology to measure the respondents' attention on an emblem of the cars. Eye tracking tools analyze fixations and measure the attention on a specific area of interests (AOI). This study explored the maintaining time and frequency on AOI, as well as explored the size of pupil to identify the respondents' attention on the AOI. In this experiment, the logos of domestic cars (i.e., Hyundai and Kia) and foreign cars (i.e., Mercedes-Benz and BMW) were swapped to see how irrational consumer behavior impact on visual perception of car emblem.

• 한국멀티미디어학회논문지
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• 제25권7호
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• pp.945-952
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• 2022

In a market situation full of brands and products, packaging requires a differentiated design that reflects the needs and trends of the times, as well as the characteristics of the product. Therefore, in this study, through literature reviews, market research methods, questionnaire surveys, eye-tracking experiments, etc., we derived related research and current status of ramen package design, and visual expression elements that induce consumers' subjective perception and interest. As a result, the ramen package design was generally simplified and tended to visualize the spicy taste. Second, consumers buy bag ramen once a week on average at a large discount mart, consider the color of the ramen package design as important, and recognize that the aesthetics of the package design can improve quality. Finally, the spicy phrases and ramen illustrations were the first visual elements of the ramen package design, and for the longest time, attention was focused on the brand name.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.83-86
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• 2004

With the proliferation of smart devices, applications under ubiquitous environment must provide transparent access to computer resources. However, existing u-Logistics systems can not properly react on such requirements, because the status information of objects is input only in fixed milestones by system's operators. In this paper, we introduce an event notification service suitable for u-Logistics environment. The system is based on RFID infrastructure and provides real-time tracking by combining the event of objects with location information received from GPS satellites. The system also provides a graphical user interface based on a state/transition approach, making it easy that clients facilitate definition of profile, and uses XML structure to more easily represent and exchange events.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.704-707
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• 2003

The Purpose of carrier tracking and tracing is to achieve more information over shipments via carrying in mobile business .At multimodes, especially consignor wants to be aware of the exact situation and position of goods. As an innovate business model, we present CGPS(Carrier Global Positioning System) scheme usiug LEO(Low Earth Orbital) satellite. The LEO collects the data periodically and sends to the web server, and eventually customer's PC or PDA. This provides shipping company or freight forwarder with more robust information such as door status, container inside condition, etc.