• 제목/요약/키워드: Focus distance

검색결과 425건 처리시간 0.038초

초음파센서를 이용한 후방경보시스템 (A Rear Alarm System using Ultra-sonic Wave Sensor)

  • 이영노;이정현;박정수;김태현;조완희;이동현;소대화
    • 동굴
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    • 제79호
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    • pp.47-51
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    • 2007
  • As time goes by, ultrasonic wave is getting important and new technology, which is adapted to ultrasonic wave is used to industry such as home appliance, automobile, and high-tech industry. Especially, ultrasonic wave is used an alarm device whether there are things at the rear of I. It's do important device in automobile system because it can prevent car-accident from inattention of the driver. Actually, there has already been lots of the alarm device. But it's expensive and so difficult to set the device. So almost driver don't set device at their automobile. We focus on these problems. We want to make cheap md easy setting device. Ultrasonic wave sensor emits Ultrasonic-signal at outgoing part and receive part accept the signal. Sensor analyzes the signal and Distance is displayed on LCD of device. The device makes alarm if distance is near from something of rear. The device makes break-system operate to prevent drivers from crashing if distance is so near. This device is portable. So normal deriver can set it easily.

개선된 거리변환 알고리즘을 이용한 이동 로봇의 경로 계획 및 추적 (Path Planning and Tracking for Mobile Robots Using An Improved Distance Transform Algorithm)

  • 박진현;박기형;최영규
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 춘계종합학술대회
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    • pp.295-299
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    • 2005
  • 본 연구는 개선된 거리변환 알고리즘을 사용하여 로봇이 이동해야 할 경로를 생성하고, 퍼지 시스템을 사용하여 경로추적 행위기와 장애물 회피 행위기를 구현해서 로봇이 그 경로를 안전하고 효율적으로 추적하는 것을 목적으로 하였다. 개선된 거리변환 알고리즘을 이용하여 로봇의 유연한 주행을 가능하게 했으며, 또한 주행거리와 주행시간도 단축되는 것을 확인할 수 있었다. 경로생성 후 경로를 추적할 때는 퍼지 시스템을 이용한 경로추적 행위기와 장애물 회피 행위기를 선택적으로 사용해서 경로추적 중에 예상치 못한 장애물이 발견되었을 경우에도 장애물을 회피한 후에 계속해서 경로를 추적하는 것을 확인함으로써 경로생성 후의 외부환경변화에도 강인함을 볼 수 있었다.

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수용성 뿜칠형 고무 아스팔트 방수재의 시공성 평가에 관한 연구 - 재료 조건을 중심으로 - (A Study on the Workability Estimation of Water-Soluble Rubberized Asphalt Waterproofing of Spray Type - Focus on the Material Condition -)

  • 오상근;배기선;이원헌;곽규성;최은수
    • 한국건축시공학회지
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    • 제3권2호
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    • pp.141-148
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    • 2003
  • This study deals with the estimation of material properties according to the construction condition for water-soluble rubberized asphalt waterproofing material of spray type. In this study, the waterproofing material property by the spray construction method is suggested by means of estimation its tensile performance and temperature dependency according to mix proportion ratio(4:1, 8:1), referenced viscosity and solid content (A:360cps, 76%, B:580cps, 79%, C:490cps, 70%), spray angle($30^{\circ}$, $45^{\circ}$, $60^{\circ}$), and spray distance(30cm, 50cm, 70cm). The result of testing are as follows. (1) The mix proportion ratio of principal agent and hardener is 4:1. (2) The viscosity referenced and solid content are 490cps and 70%. (3) The spray angle referenced is $45.^{\circ}$ (4) The distance referenced from concrete surface to spray gun is 40~50cm.

유해산출물을 고려한 국내 컨테이너 터미널 효율성 분석 (Data Envelopment Analysis for Container Terminals Considering an Undesirable Output - Focus on Busan Port & Kwangyang Port)

  • 신창훈;정동훈
    • 한국항해항만학회지
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    • 제37권2호
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    • pp.195-201
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    • 2013
  • Recently according to increase of enlarged scale ports in conformity with increase in over size vessels and container handling service, pollutants generated from ports are increasing. In advanced countries, reduction in carbon dioxide emission assigned to them has been implemented according to the Climate Change Convention and Kyoto Protocol from 2008 to 2012 in order to lessen carbon dioxide emission. Henceforth increase in discussion on the measure of constructing Green Port and low-carbon port is expected in our nation's field of port as well, it is considered that the effort in reduction with regard to undesirable output which causes environmental problem of analysis target during measuring effectiveness. Therefore, in this study, effectiveness was estimated through directional technology distance function considering undesirable output differently from effectiveness analysis of existing container terminal, and then performed comparative analysis with the result analyzed with BCC output-oriented model. As the result of analysis, in 2007 DMU3 and DMU5, and in 2010 DMU2 and DMU4 appeared to be efficient terminals in BCC output oriented model, and in directional technology distance function model, DMU1, DMU3 in 2007, DMU3, DMU5 in 2008, DMU7 in 2009, and DMU2, DMU5 in 2010 appeared to be efficient terminals.

Neural and MTS Algorithms for Feature Selection

  • Su, Chao-Ton;Li, Te-Sheng
    • International Journal of Quality Innovation
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    • 제3권2호
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    • pp.113-131
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    • 2002
  • The relationships among multi-dimensional data (such as medical examination data) with ambiguity and variation are difficult to explore. The traditional approach to building a data classification system requires the formulation of rules by which the input data can be analyzed. The formulation of such rules is very difficult with large sets of input data. This paper first describes two classification approaches using back-propagation (BP) neural network and Mahalanobis distance (MD) classifier, and then proposes two classification approaches for multi-dimensional feature selection. The first one proposed is a feature selection procedure from the trained back-propagation (BP) neural network. The basic idea of this procedure is to compare the multiplication weights between input and hidden layer and hidden and output layer. In order to simplify the structure, only the multiplication weights of large absolute values are used. The second approach is Mahalanobis-Taguchi system (MTS) originally suggested by Dr. Taguchi. The MTS performs Taguchi's fractional factorial design based on the Mahalanobis distance as a performance metric. We combine the automatic thresholding with MD: it can deal with a reduced model, which is the focus of this paper In this work, two case studies will be used as examples to compare and discuss the complete and reduced models employing BP neural network and MD classifier. The implementation results show that proposed approaches are effective and powerful for the classification.

Optimized Working Distance of a Micro-optic OCT Imaging Probe

  • Kim, Da-Seul;Moon, Sucbei
    • Current Optics and Photonics
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    • 제4권4호
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    • pp.330-335
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    • 2020
  • We have investigated optimization of the working distance (WD) for a highly miniaturized imaging probe for endoscopic optical coherence tomography (OCT). The WD is the axial distance from the distal end of the imaging probe to its beam focus, which is demanded for dimensional margins of protective structures, operational safety, or full utilization of the axial imaging range of OCT. With an objective lens smaller than a few hundred micrometers in diameter, a micro-optic imaging probe naturally exhibits a very short WD due to the down-scaled optical structure. For a maximized WD careful design is required with the optical aperture of the objective lens optimally filled by the incident beam. The diffraction-involved effect was taken into account in our analysis of the apertured beam. In this study, we developed a simple design formula on the maximum achievable WD based on our diffraction simulation. It was found that the maximum WD is proportional to the aperture size squared. In experiment, we designed and fabricated very compact OCT probes with long WDs. Our 165-㎛-thick fiber-optic probes provided WDs of 3 mm or longer w ith reasonable OCT imaging performance.

골프 스윙궤적 및 비거리 향상을 위한 기능성 골프 이너웨어의 테이핑 기법 연구 (A study on the taping techniques of functional golf inner-wear for improving golf swing trajectory & shot distance)

  • 김정우
    • 복식문화연구
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    • 제32권1호
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    • pp.58-69
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    • 2024
  • The purpose of this study was to develop the Functional golf inner-wear by preventing the injuries and enhancing the performance of the Golf swing by checking the influence of the wearing of the functional golf inner-wear considering golf characteristics on the Swing trajectory and Shot distance. Functional inner-wear effective for golf swing was manufactured using the sports taping method. Changes in driver and iron swing before and after wearing the functional golf inner-wear manufactured in this way were measured using trackman equipment. Measurement variables were limited to Club Speed, Attack Angle, Club Path, Ball Speed, Smash Factor, and Priority. Before and after wearing functional golf inner-wear, there were statistically significant differences in driver club speed, iron club speed, driver etch angle, iron club pass, driver ball speed, driver smash factor, iron smash factor, driver carry, iron carry, and right shoulder joint proprioceptive sensory ability. As a result, functional golf inner-wear is effective for ball speed, impact, and carry by increasing club speed and efficient swing. Future research will focus on the development of functional golf that can improve the swing ability in a short game that plays an important role in the golf game through various sports taping grafting technique, textile, special material, film, Research on functional golf inner-wear.

카메라 기반 바코드 판독 시스템에서의 바코드 영상 품질 향상에 관한 연구 (Analysis of Image Quality on Camera-based Barcode Reading System)

  • 박상은;박문성;김인수;김혜규
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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    • pp.481-484
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    • 2003
  • In this paper, we propose a method that acquires proper image for barcode reading on camera-based barcode reading system. In the camera system, there is serious blurring problem, and to get proper output of the barcode, it must be solved. To solve it, we proposed two methods. The first one is to make the camera movable, so it can change the distance of focus. The other is software approach, and threshold value is revised through regression analysis. Using such process, we can notice that blurring problem can be overcome.

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KINEMATICAL FOCUS ON NGC 7086

  • Tadross, A.L.
    • 천문학회지
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    • 제38권4호
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    • pp.423-428
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    • 2005
  • The main physical parameters; the cluster center, distance, radius, age, reddening, and visual absorbtion; have been re-estimated and improved for the open cluster NGC 7086. The metal abundance, galactic distances, membership richness, luminosity function, mass function, and the total mass of NGC 7086 have been examined for the first time here using Monet et al. (2003) catalog.

근거리 무선 통신의 안전한 보안 모니터링 기법 (A Secure Monitoring Mechanism for Short Distance Wireless Communication)

  • 서대희;이임영
    • 정보처리학회논문지C
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    • 제10C권3호
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    • pp.335-344
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    • 2003
  • 무선 정보 환경의 변화에 따라 다양한 정보에 대한 풍족감이 요구되고 이에 따라 많은 근거리 무선 통신 기술들이 연구 개발되어 왔으며, 그 중에서도 최근 근거리 무선 통신의 표준으로 각광받고 있는 블루투스와 무선랜은 많은 관심을 받고 있다. 그러나 근거리 무선 통신을 실제 무선 환경에 적용하기엔 많은 문제점들이 제기되고 있다. 따라서 본 논문에서는 현재 근거리 무선 통신의 보안적 취약점 뿐만 아니라 무선 환경이라는 특수한 환경에서 보안적 사항과 사용자의 프라이버시와 밀접한 관계가 있는 비보안적인 사항까지 고려한 일반화된 중앙 집중형 보안 모니터링 기법을 제안한다. 또한 제안된 방식을 근거리 무선 통신의 대표적인 기술인 블루투스와 무선랜에 적용시켜 사용자 중심으로 흩어져 있는 모바일 디바이스에 대한 안전한 보안 모니터링 기법을 제안한다.