• 한국어류학회지
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• 제20권3호
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• pp.224-227
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• 2008

학치과(Family Gobiesocidae)에 속하는 Aspasma minima 1개체가 제주도 조천읍 함덕리 연안에서 처음 채집되어 형태형질을 조사하였다. 이 종은 등지느러미 기조수 6~9개, 뒷지느러미 기조수 5~9개, 가슴지느러미 기조수 20~24개, 그리고 몸과 머리에는 많은 붉은 점이 산재하고, 위턱의 뒤 가장자리가 눈의 앞부분까지 도달하지 않는 특징을 갖고 있다. 이 미기록종의 신한국명을 "꼬마학치"라고 명명하였다.

• 한국어류학회지
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• 제30권3호
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• pp.170-174
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• 2018

농어목 전갱이과에 속하는 Caranx melampygus 1개체(표준체장 113 mm)가 2010년 8월 13일 제주도 서귀포시 대포동의 정치망에서 처음으로 채집되었다. 이 종은 형태적으로 우리나라에 서식하고 있는 줄전갱이(C. sexfasiatus)와 유사하지만 주둥이 끝이 눈의 말단을 이르지 않는 점과 주새개골의 상단에 검은 반점이 없는 것이 특징이다. 이 미기록종의 종명은 줄전갱이와 비교할 때 상대적으로 작은 입을 가지고 있어서 "작은입줄전갱이"로 제안한다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.35-40
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• 2006

Ultrasonic cold forging technology (UCFT) utilizing ultrasonic vibration energy is a method to induce severe plastic deformation to a material surface, therefore the structure of the material surface becomes a nano-crystal structure from the surface to a certain depth. It improves the mechanical properties; hardness, compressive residual stress, wear and fatigue characteristics. Applying UCFT to a rolling process in the steel industry is introduced in this study. First, the UCFT specimens of a tool steel (SKD-61/equivalent H13) are prepared and tested to verify the effects of the UCFT in a variety of mechanical properties, the UCFT is applied to the trimming knives in a cold rolling process. It has been determined that UCFT improves the mechanical properties effectively and becomes a practical method to improve productivity and reliability by about two times compared with the conventionally treated tooling in the trimming process in a cold rolling line.

• 제어로봇시스템학회논문지
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• 제19권6호
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• pp.547-554
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• 2013

This paper proposes a novel formation algorithm of identical robots based on object tracking method using omni-directional images obtained through fisheye lenses which are mounted on the robots. Conventional formation methods of multi-robots often use stereo vision system or vision system with reflector instead of general purpose camera which has small angle of view to enlarge view angle of camera. In addition, to make up the lack of image information on the environment, robots share the information on their positions through communication. The proposed system estimates the region of robots using SURF in fisheye images that have $360^{\circ}$ of image information without merging images. The whole system controls formation of robots based on moving directions and velocities of robots which can be obtained by applying Lucas-Kanade Optical Flow Estimation for the estimated region of robots. We confirmed the reliability of the proposed formation control strategy for multi-robots through both simulation and experiment.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.601-605
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• 2009

We have proposed a measurement system for measuring a whole shape of an object easily. The proposed system consists of a camera and a cylinder whose inside is coated by a mirror layer. A target object is placed inside the cylinder and an image is captured by the camera from right above. The captured image includes sets of points that are observed from multiple viewpoints: one is observed directly, and others are observed via the mirror. Therefore, the whole shape of the object can be measured using stereo vision in a single shot. This paper shows that a prototype of the proposed system was implemented and an actual object was measured using the prototype. A method based on a pattern matching which uses a value of SSD (Sum of Squared Difference), and a method based on DP (Dynamic Programming) are employed to identify a set of corresponding points in warped captured images.

• 대기
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• 제28권3호
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• pp.317-324
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• 2018

In this study, we review the ground-based whole-sky camera (WSC), which is developed to continuously capture day and night cloud images using the illumination data from a precision Lightmeter with a high temporal resolution. The WSC is combined with a precision Lightmeter developed in IYA (International Year of Astronomy) for analysis of an artificial light pollution at night and a DSLR camera equipped with a fish-eye lens widely applied in observational astronomy. The WSC is designed to adjust the shutter speed and ISO of the equipped camera according to illumination data in order to stably capture cloud images. And Raspberry Pi is applied to control automatically the related process of taking cloud and sky images every minute under various conditions depending on illumination data from Lightmeter for 24 hours. In addition, it is utilized to post-process and store the cloud images and to upload the data to web page in real time. Finally, we check the technical possibility of the method to observe the cloud distribution (cover, type, height) quantitatively and objectively by the optical system, through analysis of the captured cloud images from the developed device.

• 제어로봇시스템학회논문지
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• 제21권8호
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• pp.766-772
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• 2015

This paper proposes an object detection method based on motion estimation using background subtraction in the fisheye images obtained through omni-directional camera mounted on the vehicle. Recently, most of the vehicles installed with rear camera as a standard option, as well as various camera systems for safety. However, differently from the conventional object detection using the image obtained from the camera, the embedded system installed in the vehicle is difficult to apply a complicated algorithm because of its inherent low processing performance. In general, the embedded system needs system-dependent algorithm because it has lower processing performance than the computer. In this paper, the location of object is estimated from the information of object's motion obtained by applying a background subtraction method which compares the previous frames with the current ones. The real-time detection performance of the proposed method for object detection is verified experimentally on embedded board by comparing the proposed algorithm with the object detection based on LKOF (Lucas-Kanade optical flow).

• 한국어류학회지
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• 제26권4호
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• pp.340-344
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• 2014

농어목 전갱이과에 속하는 Pseudocaranx dentex 1개체가 2014년 7월 14일 제주도 성산해역의 정치망에서 채집되었다. 이 종은 체측에 1개의 노랑줄무늬가 있는 점, 양턱에는 송곳니가 일렬로 줄지어 있는 점, 주새개골 위부분에는 1개의 선명한 검은색 반점을 가지는 점 그리고 주둥이는 눈지름보다 길게 돌출되는 점이 특징이다. 이 미기록종의 속명과 종명은 각각 "흑점줄전갱이속"과 "흑점줄전갱이"로 제안한다.

• 제어로봇시스템학회논문지
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• 제21권7호
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• pp.634-640
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• 2015

This paper proposes a novel three-dimensional mapping algorithm in Omni-Directional Vision SLAM based on a fisheye image and laser scanner data. The performance of SLAM has been improved by various estimation methods, sensors with multiple functions, or sensor fusion. Conventional 3D SLAM approaches which mainly employed RGB-D cameras to obtain depth information are not suitable for mobile robot applications because RGB-D camera system with multiple cameras have a greater size and slow processing time for the calculation of the depth information for omni-directional images. In this paper, we used a fisheye camera installed facing downwards and a two-dimensional laser scanner separate from the camera at a constant distance. We calculated fusion points from the plane coordinates of obstacles obtained by the information of the two-dimensional laser scanner and the outline of obstacles obtained by the omni-directional image sensor that can acquire surround view at the same time. The effectiveness of the proposed method is confirmed through comparison between maps obtained using the proposed algorithm and real maps.

• 한국지능시스템학회논문지
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• 제15권5호
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• pp.560-566
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• 2005

본 논문은 유비쿼터스 이동로봇의 자기위치인식에 적용되는 비젼시스템의 왜곡된 영상을 보정하기 위한 실용적인 방법을 제안하다. 이동로봇에서 자기위치인식은 필수적인 요소이며 카메라 비젼시스템을 이용하여 처리 가능하다. 자기위치인식에서 비젼시스템은 넓은 시야를 확보하기 위해 어안렌즈를 이용하는데, 이는 영상의 왜곡을 발생한다. 또한 이동로봇은 지속적인 움직임을 가지므로 빠른 시간 내에 영상을 처리하여 자기위치를 인식해야 한다. 따라서 이동로봇에 적용 가능한 실용적인 영상왜곡 보정기법을 제안하고 실험을 통하여 성능을 검증한다.