• Proceedings of the KIEE Conference
• /
• 1994.11a
• /
• pp.302-304
• /
• 1994

In this paper, we introduce the current implementation status of the absolute position recognition technique using sonars for the navigation of a mobile robot. Using this technique, we have developed the supervisory controller of the autonomous vacuum cleaning robot which can recognize the user-specified origin, moves its body to the origin, and follow the specified trajectory starting from the origin. With the satisfactory results, we expect the autonomous cleaning robot to be commercialized in a very near future.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2013.05a
• /
• pp.363-366
• /
• 2013

오늘날 도난방지, 화재, 범죄예방 등의 안전한 생활을 위한 감시 시스템의 중요성이 강조되고 있다. 이에 영상보안 시장 규모가 급속히 증가하고 있으며 관련 기술도 인공지능을 겸비한 형태로 발전하고 있다. 우리나라도 영상보안 시스템의 수요가 2002년부터 기업과 정부를 중심으로 증가하고 있으며 급속한 성장을 거듭하는 추세는 2012년 이후에도 지속될 전망이다. 특히, 최근에는 적은 대수의 카메라로 보다 넓은 지역을 관찰하고 특정 부분을 확대 관찰할 수 있는 PTZ 카메라의 활용이 증가하고 있다. PTZ 카메라는 카메라에 구동 장치를 추가하여 좌우(Pan), 상하(Tilt)로 카메라의 시점을 이동시킬 수 있으며 특정 부분을 확대하여 관찰할 수 있는 줌(Zoom) 기능을 가진 카메라를 말한다. 이와 같은 장점으로 지능형 PTZ 카메라는 점차 대중화 되고 있다. 하지만, 현재 시중에 판매되는 많은 종류의 PTZ 카메라를 이용한 영상보안 감시는 실제로 사용자들이 동작하고 사용하는데 있어서 많은 문제점을 가지고 있다. 이에 본 논문에서는 카메라 별로 제공하는 상이하고 왜곡된 좌표 값에서 새롭게 가공한 직관적 절대좌표 값을 추출하여 정확한 목표지점으로의 위치이동과 간편한 카메라 조작을 위한 시스템을 설계하였다.

• The Journal of the Acoustical Society of Korea
• /
• v.25 no.2
• /
• pp.72-77
• /
• 2006

British acoustics in the nineteenth century is important as a foundation for modern acoustics in the history of acoustics. The Purpose and objective of acoustics was different from those in modern age. and musical motivation was distinguished among them. This study intends to clarify various aspects of interaction between music and acoustics in nineteenth-century Britain by examining related materials in both published and unpublished forms. Then music Provided acoustics with instruments, subjects, and personnel, and acoustics did much as musical science in helping to improve and develop musical scales and enhancing the exactness of measurement of absolute pitches. Music played an essential role in developing acoustics to a modern discipline in Europe, especially in Britain. all through the nineteenth century.

• Science of Emotion and Sensibility
• /
• v.16 no.1
• /
• pp.29-42
• /
• 2013

In this paper, we analyze the effect of the depth perception, volume perception and visual discomfort according to the change of the quality of the depth image and the depth of the major object. For the analysis, a 2D image was converted to eighteen 3D images using depth images generated based on the different depth position of a major object and background, which were represented in three detail levels. The subjective test was carried out using eighteen 3D images so that the degrees of the depth perception, volume perception and visual discomfort recognized by the subjects were investigated according to the change in the depth position of the major object and the quality of depth map. The absolute depth position of a major object and the relative depth difference between background and the major object were adjusted in three levels, respectively. The details of the depth map was also represented in three levels. Experimental results showed that the quality of the depth image differently affected the depth perception, volume perception and visual discomfort according to the absolute and relative depth position of the major object. In the case of the cardboard depth image, it severely damaged the volume perception regardless of the depth position of the major object. Especially, the depth perception was also more severely deteriorated by the cardboard depth image as the major object was located inside the screen than outside the screen. Furthermore, the subjects did not felt the difference of the depth perception, volume perception and visual comport from the 3D images generated by the detail depth map and by the rough depth map. As a result, it was analyzed that the excessively detail depth map was not necessary for enhancement of the stereoscopic perception in the 2D-to-3D conversion.

• Journal of KIISE:Information Networking
• /
• v.34 no.5
• /
• pp.370-378
• /
• 2007

In wireless sensor networks (WSNs), thousands of sensors are often deployed in a hostile environment. In such an environment, WSNs can be applied to various applications by using the absolute or relative location information of the sensors. Until now, the time-of-arrival (TOA) based localization method has been considered most accurate. In the TOA method, however, inaccuracy in distance estimation is caused by clock drift and clock skew between sensor nodes. To solve this problem, several numbers of periodic time synchronization methods were suggested while these methods introduced overheads to the packet traffic. In this paper, we propose a new localization method based on multiple round-trip times (RTOA) of a signal which gives more accurate distance and location estimation even in the presence of clock skew between sensor nodes. Our experimental results show that the Proposed RTOA method gives up to 93% more accurate location estimation.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.7B
• /
• pp.595-601
• /
• 2006

This study presents an ultrasonic location awareness system for the ubiquitous computing with absolute position. The flight time of ultrasonic waves is determined by a period detecting technique which is able to extend the sensing range compared with traditional methods. For location awareness, ultrasonic waves are sent successively from each ultrasonic transmitter and synchronized by radio frequency (RF) signal, where the transmitting part is fixed and the receiving part is movable. To expand the recognizing range, cell matching technique and coded ultrasonic technique are introduced. The experimentation for various distances is accomplished to verify the used period detecting technique of U-SAT system. The positioning accuracy by using cell matching is also verified by finding the locations of settled points and the usability of coded ultrasonic technique is verified. As a result, the possibility of ultrasonic location awareness system for the ubiquitous computing can be discussed as a pseudo-satellite system with low cost, a high update rate, and relatively high precision, in the places where GPS is not available.

• Journal of Internet Computing and Services
• /
• v.14 no.6
• /
• pp.9-18
• /
• 2013

In this paper, we design and implement an intelligent system for finding objects with RFID(Radio Frequency IDentification) tag in which an mobile robot can do. The system we developed is a learning system of artificial neural network that uses RSSI(Received Signal Strength Indicator) value as input and absolute coordination value as target. Although a passive RFID is used for location estimation, we consider an active RFID for expansion of recognition distance. We design the proposed system and construct the environment for indoor location estimation. The designed system is implemented with software and the result related learning is shown at test bed. We show various experiment results with similar environment of real one from earning data generation to real time location estimation. The accuracy of location estimation is verified by simulating the proposed method with allowable error. We prepare local test bed for indoor experiments and build a mobile robot that can find the objects user want.

• Korean Journal of Head & Neck Oncology
• /
• v.10 no.1
• /
• pp.53-62
• /
• 1994

미세외과 수술에 의한 유리 피판술의 도입은 두경부 종양제거후 재건에 괄목할 만한 진보를 가져왔다. 특히 광범위한 종양의 제거가 필요하며 인근의 조직으로 수복이 어렵고 기능 및 외모상의 재건이 문제가 되는 경우 유리 피판은 절대적인 적응이 된다. 구강은 언어구사 와 연하(deglutition)기능을 담당하므로 재건을 위해서는 얇고 부드러운 조직으로 수복하여 주어야 한다. 전완부 유리피판은 혈관경의 위치가 대부분 일정하고 종양 제거후 결손의 모양에 따라 피판을 계획할 수 있기 때문에 구강암 제거후 가장 많이 이용되는 유리피판이다. 저자는 1982년 부터 1988년까지 영국 글라스고우 소재 서부 스코틀랜드 성형 및 구강외과 병원에서 구강의 편평상피암환자로 암종제거 후, 전완부 피판에 의한 재건 및 방사선 치료를 받은 151명의 치료결과(재발율 및 생존율)를 분석하였다. 절제연의 종양조직의 양성(P<0.05), 경부 임파절의 extracapsular node spread여부(P<0.001), 경부 임파절 곽청술의 종류(P<0.05) 등은 재발율과 관련하여 통계적으로 유의하였다. 반면에 종양의 구강내 위치, 하악골의 침범여부등은 통계적의의가 없었다. 생존율에 관하여는 종양의 구강내 위치 (P<0.05), 종양절제연 종양여부(P<0.005), 하악골의 침범여부(P<0.05), 경부 임파절의 extracapsular node spread여부(P<0.001) 등이 통계적으로 유의할 만한 요소로 밝혀졌다. 젊은 나이의 환자들에서(50세이하) 특징적으로 높은 사망률을 보였다. 하악골절제방법의 차이는 환자의 생존예후에 통계적으로 유의할 만한 영향을 주지 못했다.

• Spatial Information Research
• /
• v.19 no.3
• /
• pp.33-42
• /
• 2011

Since the method of generating 3D Spatial Information using aerial photographs was introduced, lots of researches on effective generation methods and applications have been performed. Nadir and oblique imagery are acquired in a same time by Pictometry system, and then 3D positioning is processed as Multi-Looking Camera procedure. In this procedure, the number of GCPs is the main factor which can affect the accuracy of true-orthoimage. In this study, 3D positioning accuracies of true-orthoimages which had been generated using various number of GCPs were estimated. Also, the standard of GCP number and distribution were proposed.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.13 no.2
• /
• pp.229-236
• /
• 1995

This study is the 3-D positional analysis for track of magnetically levitated vehicles to precise construction and periodical safe diagnosis by photogrammetry. In the result, we could improve the accuracy of Z as well as X, Y using the modified control points of spatial distribution to the plane distribution of the absolutly effective control points to accuracy and diagnosis the the track of magnetically levitated vehicles using the below 1㎜ accuracy. And we could analysis the 3-D precise positions and efficiently decide the geometric characteristics of the cant and gradient to the instrument.