• International Journal of Ocean System Engineering
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• 제1권2호
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• pp.68-75
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• 2011

This paper addresses an underwater landmark for updating UUV positioning information. A method is proposed in which the landmark's cubic shape and edge are recognized. The reliability, installation load, and management of landmark design were taken into consideration in order to assess practical applications of the landmark. Landmark recognition was based on topological features. The straight line recognition confirmed the landmark's location and enabled an UUV to accurately estimated its underwater position with respect to the landmark. An efficient recognition method is proposed, which provides real-time processing with limited UUV computing power. An underwater experiment was conducted in order to evaluate the proposed method's reliability and accuracy.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.164-169
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• 2009

As one of the most interesting scenes, landmarks constitute a large percentage of the vast amount of scene images available on the web. On the other hand, a specific "landmark" usually has some characteristics that distinguish it from surrounding scenes and other landmarks. These two observations make the task of accurately estimating geographic information from a landmark image necessary and feasible. In this paper, we propose a method to identify landmark location by means of landmark recognition in view of significant viewpoint, illumination and temporal variations. We use GPS-based clustering to form groups for different landmarks in the image dataset. The images in each group rather fully express the possible views of the corresponding landmark. We then use a combination of edge and color histogram to match query to database images. Initial experiments with Zubud database and our collected landmark images show that is feasible.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2012년도 추계학술발표대회
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• pp.1183-1185
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• 2012

본 논문은 최근 항만 터미널 장치장 내 무인 자동화가 빠르게 연구 진행되고 있는 가운데 다양한 자동화 기술들이 제공되고 있다. 우리는 장치장 내 효과적인 작업 효율을 위하여 RFID(Radio Frequency Identification)를 이용한 무인이송장비(YT:Yard Tractor)의 정지위치 인식 시스템을 제안한다. 제안된 시스템은 장치장내에서 YT의 정지하고자 하는 장소에서 RFID의 신호와 LANDMARK를 이용하여 정지한다. 정지 위치 장소에 두 개의 RFID태그를 설치하여 작업영역 및 정지위치를 각각의 태그 정보에 포함시킨다. YT는 정지장소에 도달하면 지정된 작업 영역인지 태그 정보를 통해 확인하고, 확인 후 정지위치정보를 포함하는 태그와 LANDMARK를 통해 정확한 위치에 정지한다.

• IEIE Transactions on Smart Processing and Computing
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• 제5권3호
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• pp.178-184
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• 2016

This paper proposes a new path-finding scheme using viewpoint-invariant landmarks. The scheme introduces the concept of landmark detection in images captured with a vision sensor attached to a mobile robot, and provides landmark clues to determine a path. Experiment results show that the scheme efficiently detects landmarks with changes in scenes due to the robot's movement. The scheme accurately detects landmarks and reduces the overall landmark computation cost. The robot moves in the room to capture different images. It can efficiently detect landmarks in the room from different viewpoints of each scene. The outcome of the proposed scheme results in accurate and obstacle-free path estimation.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2011년도 추계학술발표대회
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• pp.177-180
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• 2011

In practice, it is well known that geographical and/or location based routing is highly effective for wireless sensor network. Here, electing some landmarks on the network and forwarding data based on the landmark is one of the good approaches for a vast sensing field with holes. In the most previous works, landmarks are elected without considering the residual energy on each sensor. In this paper, we propose an Energy aware Landmark Election and Routing (ELER) protocol to establish a stable routing paths and reduce the total power consumption. The proposed protocol makes use of each sensor's energy level on electing the landmarks, which would be utilized to route a packet towards the target region using greedy forwarding method. Our simulation results illustrate that the proposed scheme can significantly reduce the power dissipation and effectively lengthen the lifetime of the network.

• 제어로봇시스템학회논문지
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• 제7권9호
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• pp.749-757
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• 2001

본 논문에서는 이동 로봇의 자기 위치 추(self-localization)을 위해 간단하고 효육적인 컬러 표식 모델과 추적 기법을 제안하고, 제안된 표식을 이용한 위치 추정 기법을 제안한다. 본 논문에서 제안한 표식모델은 대칭적이고 반복적인 컬러 패턴을 갖는데. 이러한 기하학적 형태로 인해 표식 모델은 기하학적 변형이나 광학적 변형에 대해 불변인 히스토그램 특성을 나타낸다. 이러한 특징을 영상 내 표식 검출 및 추적을 위한 유사 척도로 사용하고 컨데세이션(CONDENSATION)에 기반한 확률적 접근 방식을 통해 복잡한 환경 하에서도 표식 모델을 강인하게 추적할 수 있다. 표식 모델이 검출된 후에는 표식이 갖는 기하작적 정보를 이용하여 이동 로봇과표식간의 상대적인 위치를 정확하게 추정한다.

• 디지털융복합연구
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• 제10권7호
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• pp.123-128
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• 2012

본 논문에서는 보다 정확한 물체 인식을 위하여 물체의 특징점 검출 시스템을 제안한다. 물체의 특징점 검출 시스템은 학습 단계와 검출 단계로 구분된다. 학습 단계에서는 각 특징점의 탐색영역을 설정하기 위한 관심영역모델과 탐색영역에서 특징점을 검출하기 위한 각 특징점별 검출기를 생성한다. 검출 단계에서는 학습 단계에서 생성했던 관심영역모델을 이용하여 입력 영상에서 각각의 특징점의 탐색영역을 설정한다. 시스템에서 검출하고자 하는 특징점 검출 방법은 고속 푸리에 변환을 이용하기 때문에 검출 속도가 빠르며 물체의 추적 시 실패하는 확률이 낮아진다. 제안하는 방법을 개발하여 실험 영상에 적용한 결과 추적하고자 하는 물체가 불규칙적인 속도로 움직일 때에도 안정적으로 추적함을 알 수 있었다. 실험 결과는 기존의 방법들에서 사용되었던 다양한 데이터 집합에 적용하였을 때 우수한 성능을 보여준다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권9호
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• pp.3685-3700
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• 2015

To avoid influences caused by pose, illumination and facial expression variations, we propose a robust three-step algorithm based on ASM and POEM for facial landmark localization. Firstly, Model Selection Factor is utilized to achieve a pose-free initialized shape. Then, we use the global shape model of ASM to describe the whole face and the texture model POEM to adjust the position of each landmark. Thirdly, a second localization is presented to discriminatively refine the subtle shape variation for some organs and contours. Experiments are conducted in four main face datasets, and the results demonstrate that the proposed method accurately localizes facial landmarks and outperforms other state-of-the-art methods.

• International Journal of Contents
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• 제2권3호
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• pp.27-32
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• 2006

We present an effective algorithm for automatic tracing of retinal vessel structure and vascular landmark extraction of bifurcations and ending points. In this paper we deal with vascular patterns from RGB images for personal identification. Vessel tracing algorithms are of interest in a variety of biometric and medical application such as personal identification, biometrics, and ophthalmic disorders like vessel change detection. However eye surface vasculature tracing in RGB images has many problems which are subject to improper illumination, glare, fade-out, shadow and artifacts arising from reflection, refraction, and dispersion. The proposed algorithm on vascular tracing employs multi-stage processing of ten-layers as followings: Image Acquisition, Image Enhancement by gray scale retinal image enhancement, reducing background artifact and illuminations and removing interlacing minute characteristics of vessels, Vascular Structure Extraction by connecting broken vessels, extracting vascular structure using eight directional information, and extracting retinal vascular structure, and Vascular Landmark Extraction by extracting bifurcations and ending points. The results of automatic retinal vessel extraction using jive different thresholds applied 34 eye images are presented. The results of vasculature tracing algorithm shows that the suggested algorithm can obtain not only robust and accurate vessel tracing but also vascular landmarks according to thresholds.

• Journal of International Society for Simulation Surgery
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• 제3권1호
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• pp.9-11
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• 2016

Purpose In this paper we proposed bi-directional hierarchical regression for accurate human finger landmark detection with only using depth information.Materials and Methods Our algorithm consisted of two different step, initialization and landmark estimation. To detect initial landmark, we used difference of random pixel pair as the feature descriptor. After initialization, 16 landmarks were estimated using cascaded regression methods. To improve accuracy and stability, we proposed bi-directional hierarchical structure.Results In our experiments, the ICVL database were used for evaluation. According to our experimental results, accuracy and stability increased when applying bi-directional hierarchical regression more than typical method on the test set. Especially, errors of each finger tips of hierarchical case significantly decreased more than other methods.Conclusion Our results proved that our proposed method improved accuracy and stability and also could be applied to a large range of applications such as augmented reality and simulation surgery.