• 제목/요약/키워드: proximity point

검색결과 112건 처리시간 0.034초

방위각 CPA를 이용한 수중표적의 CPA 거리와 속도의 비 추정 (Estimating The Ratio of The CPA Distance to Velocity for Underwater Target using Bearing CPA)

  • 김정훈;윤경식;서익수;이균경
    • 전자공학회논문지
    • /
    • 제53권6호
    • /
    • pp.146-151
    • /
    • 2016
  • 본 논문에서는 등속 직선 기동하는 수중표적의 CPA 상황에서의 방위각 정보를 이용하여 표적의 CPA 거리와 속도의 비를 추정하는 기법을 제시한다. 선행 연구를 통해 근접센서를 이용한 포락선 CPA 기법으로 이 값을 추정하는 방안이 제시되었으나, 이는 표적과 수신 센서의 거리가 가깝거나 다중경로로 인한 간섭효과가 커질 경우 성능이 떨어지는 문제를 가진다. 이에 이를 극복하는 방안으로 표적 방위각 정보를 이용하는 방위각 CPA 기법을 제시한다.

Clustering Patterns in the Manufacturing Sectors of Japan

  • Carvajal, Carlos A.;Watanabe, Chihiro
    • 기술혁신연구
    • /
    • 제12권2호
    • /
    • pp.99-126
    • /
    • 2004
  • Japan's economic clusters are characterized by their high level of diversity. In essence, Japanese economic clusters are not limited to single industries; they comprise numerous manufacturing industries and firms which cluster in specific heterogeneous economic zones, vice political boundaries. Japanese manufacturing sectors are showing an increased level of diversity, resulting in the spread of experience and knowledge among clusters, and sustained growth at the point of industrial structural transformation. Japan's Ministry of Education, Culture, Sports, Science and Technology (MEXT) proposed the creation of intellectual clusters for the purpose of promoting research and development(R&D) activities resulting in the stimulation and development of new technologies. The Ministry of Economy Trade and Industry (METI) is also proposing the industrial cluster plan with the aim to promote the local rebirth and revitalization of the Japanese industrial sector. This paper proposes a methodological analysis which will result in the integration of the two policies currently implemented by the Japanese government. If the current policies are not coordinated and integrated, artificial firms and sectors will continue to hamper innovation and discourage competitiveness, which will ultimately result in Japan's loss of economic opportunities within Asia. In the worst case, failure to act on current economic deficiencies illuminated in this paper could cost Japan its position as an Asian economic leader.

  • PDF

주행 슬립 오차 보상기를 가지는 레일 가이드 무인 설비 감시 장치의 위치 제어기 (Position Controller of Rail Guided Unmanned Monitoring System with the Driving Slip Compensator)

  • 배종남;곽윤창;이동희
    • 전기학회논문지
    • /
    • 제66권5호
    • /
    • pp.792-799
    • /
    • 2017
  • The real time unmanned monitoring system of an equipment's internal parts and condition requires the monitoring device to be able to stop at a set location on the rail. However, due to the slip between the driving surface and the roller, an error occurs between the actual position and the command position. In this paper, a method to compensate the position error due to the roller slip is proposed. A proximity sensor located at both ends of the rail detects the starting point and the maximum position pulse, linearly compensating the error between the angular position of the motor and the mechanically fixed starting and maximum position pulse of the rail in forward and reverse direction. Moreover, unlike the existing servo position controller, the motor adopts the position detection method of Hall sensor in BLDC (Brushless DC) and applies an algorithm for low-speed driving so that a stable position control is possible. The proposed rail guided unmanned monitoring system with driving slip compensator was tested to verify the effectiveness.

우리나라의 동북아 물류거점화전략과 관세자유지역제도의 발전방향 (A study on Korean Free Zone and it's growing strategy)

  • 강종희;우종균
    • 무역상무연구
    • /
    • 제16권
    • /
    • pp.117-154
    • /
    • 2001
  • The objective of the study is to propose to the strategy to make korean main ports to international logistics center in Northeast Asia. so this study's construction is constructed four steps. First, analysis the environment of economy, business and logistics industry in Northeast Asia. Second, analysis the constructions and characters of Free Zone Act. Third, analysis of Korean Government's policy about Free Zone. Forth, propose the growing strategy of Free Zone. In 1999 Northeast Asia was adopted in Korea, which will facilitate the process and strengthen the international logistics capability as a international logistics hub in Northeast Asia. But only adoption in the point of law is not enough to growing korean main seaport and airport to a international logistics hub. so various strategies are needed. In this study, we propose the growing strategies that are to establish and manage the free zone of ports and its hinterland are: the establishment of a long-term vision of international logistics complexes, the improvement of the proximity to markets/customers by way of linkage of global networks, the activation of the industrial complex in hinterland, the development of the skilled labor and the labor climate, the cooperation between governmental bodies and government/provincial bodies, continuous development of logistics infrastructure and so on.

  • PDF

자기교차를 가지는 곡선 재구성 (Reconstructing Curves With Self-intersections)

  • 김형석
    • 한국정보통신학회논문지
    • /
    • 제14권9호
    • /
    • pp.2016-2022
    • /
    • 2010
  • 점들의 집합으로부터 곡선이나 곡면을 구성하는 문제는 기하학적 모델링, 컴퓨터그래픽스, 영상처리 등의 분야에서 중요한 역할을 수행하고 있다. 특히 곡선 재구성 문제는 기존에 존재하는 곡선으로부터 샘플링된 점들로부터 순서를 부여하여 점들을 연결하는 문제이다. 이러한 문제에 대한 대부분의 기존 방법들은 유클리언 거리를 기초로 하고 있기 때문에 자기교차를 가지고 있는 곡선의 재구성 문제를 해결하지 못하고 있는 실정이다. 본 논문에서는 이러한 문제점을 해결하기 위하여 방향도 함께 고려하는 거리를 제안하고, 이를 이용하여 데이터 점들에게 순서를 부여하는 알고리즘을 제안한다. 본 논문에서 제안하는 거리함수는 브라운 운동의 확산 특성을 반영한 것으로서, 다음 점의 위치에 대한 정보를 표준정규분포로 전환함에 의해서 유도되었다. 본 논문의 우수성은 기존의 방법으로는 해결하지 못했던 자기교차 곡선 재구성 문제를 해결할 수 있다는 점이다.

고립된 사용자 밀집지역을 위한 D2D 광고 확산 알고리즘 성능 분석 (Performance Evaluation of D2D Advertisement Dissemination Algorithm for Isolated High User-Density Area)

  • 김준선;이호원
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2015년도 춘계학술대회
    • /
    • pp.40-42
    • /
    • 2015
  • D2D(Device-to-Device) 통신과 소셜커머스 서비스를 결합한 D2D 광고 확산 알고리즘은 소상공인들을 위한 효율적인 광고를 가능하게 한다. D2D 광고 확산 알고리즘에서는 효율적인 광고 확산을 위해 사용자 밀집도를 기반으로 목표지역을 설정하고 인접한 목표지역들은 그룹을 형성한다. 광고는 형성된 그룹을 기반으로 확산된다. 그룹을 형성하지 못한 고립된 목표지역들은 AP(Access Point)와의 거리에 따라 그룹 형성 여부가 결정한다. 본 논문에서는 시뮬레이션을 통해 고립된 사용자 밀집지역을 위한 최대 거리 변화에 따른 성공적으로 수신한 전체 사용자 수와 평균 릴레이 유저의 수에 대한 성능을 비교 분석한다.

  • PDF

Sound change of /o/ in modern Seoul Korean: Focused on relations with acoustic characteristics and perception

  • Igeta, Takako;Sonu, Mee;Arai, Takayuki
    • 말소리와 음성과학
    • /
    • 제6권3호
    • /
    • pp.109-119
    • /
    • 2014
  • This article represents a first step in a large study aimed at elucidating the relationship between production and perception involved in sound change of /o/ in (Seoul) Korean. In this paper we present the results of a production study and a perception experiment. For the production study we examined vowel production data of 20 young adult speakers, measuring the first and second formants, then conducted a discriminant analysis based on those values. In terms of their F1-F2 values, the distribution of /o/ and /u/ were close, and even overlapping in some circumstances, which is consistent with the literature. This tendency was more apparent among the female speakers than the males. Moreover, with the females' distributions, /o/ was frequently categorized as /u/, suggesting that the direction of the sound change is indeed increasing from /o/ to /u/. Next, to investigate the effects of this proximity on perception, we used the production data of five randomly selected speakers from the production study as stimuli for a perception experiment in which 21 young adult native speakers of (Seoul) Korean performed a vowel identification task and provided a Goodness rating on a 5-point scale. We found that while rates of correctness were high, when these correctness scores were weighted by the Goodness rating, these "weighted correctness" scores were lower in some cases, indicating a degree of confusion in distinguishing between the two vowels.

영상처리를 이용한 Mark 판독 기법에 관한 연구 (A Study on the Mark Reader Using the Image Processing)

  • 김승호;김범진;이용구;노도환
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
    • /
    • pp.83-83
    • /
    • 2000
  • Recently, Vision system has being used all around industry. Sensor systems are used for Mark Reader, for example, optical scanning is proximity sensor system, have many disadvantages, such as, lacking user interface and difficulty to store original specimens. In contrast with this, Vision systems for Mark Reader has many advantages, including function conversion to achieve other work, high accuracy, high speed, etc. In this thesis, we have researched the development of Mark Reader by using a Vision system. The processing course of this s)'stem is consist to Image Pre-Processing such as noise reduction, edge detection, threshold processing. And then, we have carried out camera calibration to calibrate images which are acquired from camera. After searching for reference point within scanning area(60pixe1${\times}$30pixe1), we have calculated points crossing by using line equations. And then, we decide to each ROI(region of interest) which are expressed by four points. Next we have converted absolute coordinate into relative coordinate for analysis a translation component. Finally we carry out Mark Reading with images classified by six patterns. As a result of experiment which follows the algorithm has proposed, we have get error within 0.5% from total image.

  • PDF

Earthquake behavior of M1 minaret of historical Sultan Ahmed Mosque (Blue Mosque)

  • Kocaturk, Turgut;Erdogan, Yildirim Serhat
    • Structural Engineering and Mechanics
    • /
    • 제59권3호
    • /
    • pp.539-558
    • /
    • 2016
  • Minarets are almost the inevitable part of Mosques in Islam and according to some, from a philosophical point of view, today they symbolize the spiritual elevation of man towards God. Due to slenderness, minarets are susceptible to earthquakes and wind loads. They are mostly built in a masonry style by using cut limestone blocks or occasionally by using bricks. In this study, one minaret (M1 Minaret) of one of the charmest mosques of Turkey, Sultan Ahmed Mosque, popularly known as Blue Mosque, built between 1609 and 1616 on the order of Sultan Ahmed by the architect Mehmet Agha is investigated under some registered earthquake loads. According to historical records, a great earthquake hit Istanbul and/or its close proximity approximately every 250 years. Ottomans tackled with the problem of building earthquake resistant, slender minarets by starting to use forged iron connectors with lead as a filler to fix them to the upper and lower and to adjacent stones instead of using traditional mortar only. Thus, the discrete stones are able to transfer tensile forces in some sense. This study investigates the contribution of lead to the energy absorption capacity of the minaret under extensive earthquakes occurred in the region. By using the software ANSYS/LS-DYNA in modelling and investigating the minaret nonlinearly, it is found out that under very big recorded earthquakes, the connectors of vertical cast iron-lead mechanism play very important role and help to keep the structure safe.

Autonomous vision-based damage chronology for spatiotemporal condition assessment of civil infrastructure using unmanned aerial vehicle

  • Mondal, Tarutal Ghosh;Jahanshahi, Mohammad R.
    • Smart Structures and Systems
    • /
    • 제25권6호
    • /
    • pp.733-749
    • /
    • 2020
  • This study presents a computer vision-based approach for representing time evolution of structural damages leveraging a database of inspection images. Spatially incoherent but temporally sorted archival images captured by robotic cameras are exploited to represent the damage evolution over a long period of time. An access to a sequence of time-stamped inspection data recording the damage growth dynamics is premised to this end. Identification of a structural defect in the most recent inspection data set triggers an exhaustive search into the images collected during the previous inspections looking for correspondences based on spatial proximity. This is followed by a view synthesis from multiple candidate images resulting in a single reconstruction for each inspection round. Cracks on concrete surface are used as a case study to demonstrate the feasibility of this approach. Once the chronology is established, the damage severity is quantified at various levels of time scale documenting its progression through time. The proposed scheme enables the prediction of damage severity at a future point in time providing a scope for preemptive measures against imminent structural failure. On the whole, it is believed that the present study will immensely benefit the structural inspectors by introducing the time dimension into the autonomous condition assessment pipeline.