• Title/Summary/Keyword: velocity information

Search Result 2,089, Processing Time 0.025 seconds

Position Control of Wheeled Mobile Robot using Self-Structured Neural Network Model (자율가변 구조의 신경망 모델을 이용한 구륜 이동 로봇의 위치 제어)

  • Kim, Ki-Yeoul;Kim, Sung-Hoe;Kim, Hyun;Lim, Ho;Jeong, Young-Hwa
    • The Journal of Information Technology
    • /
    • v.4 no.2
    • /
    • pp.117-127
    • /
    • 2001
  • A self-structured neural network algorithm that finds optimal fuzzy membership functions and nile base to fuzzy model is proposed and a fuzzy-neural network controller is designed to get more accurate position and velocity control of wheeled mobile robot. This procedure that is composed of three steps has its own unique process at each step. The elements of output term set are increased at first step and then the rule base Is varied according to increase of the elements. The adjusted controller is in competition with controller which doesn't include any increased elements. The adjusted controller will be removed if the control-law lost. Otherwise, the controller is replaced with the adjusted system. After finished regulation of output term set and rule base, searching for input membership functions is processed with constraints and fine tuning of output membership functions is done.

  • PDF

Precise Outdoor Localization of a GPS-INS Integration System Using Discrete Wavelet Transforms and Unscented Particle Filter (이산 웨이블릿 변환과 Unscented 파티클 필터를 이용한 GPS-INS 결합 시스템의 실외 정밀 위치 추정)

  • Seo, Won-Kyo;Lee, Jang-Myung
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.48 no.6
    • /
    • pp.82-90
    • /
    • 2011
  • This paper proposes an advanced outdoor localization algorithm of a GPS(global positioning system)-INS(inertial navigation system) integration system. In order to reduce noise from the internal INS sensors, discrete wavelet transform and variable threshold method are utilized. The UPF (unscented particle filter) combines GPS information and INS signals to implement precise outdoor localization algorithm and to reduce noise caused by the acceleration, deceleration, and unexpected slips. The conventional de-noising method is mainly carried out using a low pass filter and a high pass filter which essentially result in signal distortions. This newly proposed system utilizes the vibration information of actuator according to fluctuations of the velocity to minimize signal distortions. The UPF also resolves non-linearities of the actuator and non-normal distributions of noises. Effectiveness of the proposed algorithm has been verified through the real experiments and the results are demonstrated.

Automatic National Image Interpretability Rating Scales (NIIRS) Measurement Algorithm for Satellite Images (위성영상을 위한 NIIRS(Natinal Image Interpretability Rating Scales) 자동 측정 알고리즘)

  • Kim, Jeahee;Lee, Changu;Park, Jong Won
    • Journal of Korea Multimedia Society
    • /
    • v.19 no.4
    • /
    • pp.725-735
    • /
    • 2016
  • High-resolution satellite images are used in the fields of mapping, natural disaster forecasting, agriculture, ocean-based industries, infrastructure, and environment, and there is a progressive increase in the development and demand for the applications of high-resolution satellite images. Users of the satellite images desire accurate quality of the provided satellite images. Moreover, the distinguishability of each image captured by an actual satellite varies according to the atmospheric environment and solar angle at the captured region, the satellite velocity and capture angle, and the system noise. Hence , NIIRS must be measured for all captured images. There is a significant deficiency in professional human resources and time resources available to measure the NIIRS of few hundred images that are transmitted daily. Currently, NIIRS is measured every few months or even few years to assess the aging of the satellite as well as to verify and calibrate it [3]. Therefore, we develop an algorithm that can measure the national image interpretability rating scales (NIIRS) of a typical satellite image rather than an artificial target satellite image, in order to automatically assess its quality. In this study, the criteria for automatic edge region extraction are derived based on the previous works on manual edge region extraction [4][5], and consequently, we propose an algorithm that can extract the edge region. Moreover, RER and H are calculated from the extracted edge region for automatic edge region extraction. The average NIIRS value was measured to be 3.6342±0.15321 (2 standard deviations) from the automatic measurement experiment on a typical satellite image, which is similar to the result extracted from the artificial target.

Detecting and Tracking Vehicles at Local Region by using Segmented Regions Information (분할 영역 정보를 이용한 국부 영역에서 차량 검지 및 추적)

  • Lee, Dae-Ho;Park, Young-Tae
    • Journal of KIISE:Software and Applications
    • /
    • v.34 no.10
    • /
    • pp.929-936
    • /
    • 2007
  • The novel vision-based scheme for real-time extracting traffic parameters is proposed in this paper. Detecting and tracking of vehicle is processed at local region installed by operator. Local region is divided to segmented regions by edge and frame difference, and the segmented regions are classified into vehicle, road, shadow and headlight by statistical and geometrical features. Vehicle is detected by the result of the classification. Traffic parameters such as velocity, length, occupancy and distance are estimated by tracking using template matching at local region. Because background image are not used, it is possible to utilize under various conditions such as weather, time slots and locations. It is performed well with 90.16% detection rate in various databases. If direction, angle and iris are fitted to operating conditions, we are looking forward to using as the core of traffic monitoring systems.

Estimating Method of Topographic Factor of Design Wind Speed Using GIS (GIS를 이용한 지형에 의한 풍속할증계수 산정 방법)

  • Choi, Se-Hyu;Seo, Eun-Su
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.16 no.3
    • /
    • pp.126-135
    • /
    • 2013
  • With more than 70% of the country consisting of mountains, Korea has large and small mountains, and hills located in the inner cities. Therefore, Korea's architectural structure laws stipulate that an increase in wind speed due to the influence of terrain should be considered in the design of wind loads of buildings. But if more than two mountains are located around the building or if the boundaries of the land surface are not clear when calculating topographic factors of wind speed, the designer has subjectively selected the coverage of the topographic factors of wind speed or the surface. This may lead to unscientific design of wind loads. This study attempts to analyze topographic factors of wind speed by using a 1:5000 topographic map with relatively high location accuracy and thereby to reflect changes due to the topographic characteristics and influence at the point where the building is located. By also selecting terrain surfaces and vertexes through Arc GIS and presenting a scientific approach to determine the range of topographic factors of wind speed, this study is expected to make a contribution for more rational and cost-effective wind-resistant design of buildings.

Lightweight Multicast Routing Based on Stable Core for MANETs

  • Al-Hemyari, Abdulmalek;Ismail, Mahamod;Hassan, Rosilah;Saeed, Sabri
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.8 no.12
    • /
    • pp.4411-4431
    • /
    • 2014
  • Mobile ad hoc networks (MANETs) have recently gained increased interest due to the widespread use of smart mobile devices. Group communication applications, serving for better cooperation between subsets of business members, become more significant in the context of MANETs. Multicast routing mechanisms are very useful communication techniques for such group-oriented applications. This paper deals with multicast routing problems in terms of stability and scalability, using the concept of stable core. We propose LMRSC (Lightweight Multicast Routing Based on Stable Core), a lightweight multicast routing technique for MANETs, in order to avoid periodic flooding of the source messages throughout the network, and to increase the duration of multicast routes. LMRSC establishes and maintains mesh architecture for each multicast group member by dividing the network into several zones, where each zone elects the most stable node as its core. Node residual energy and node velocity are used to calculate the node stability factor. The proposed algorithm is simulated by using NS-2 simulation, and is compared with other multicast routing mechanisms: ODMRP and PUMA. Packet delivery ratio, multicast route lifetime, and control packet overhead are used as performance metrics. These metrics are measured by gradual increase of the node mobility, the number of sources, the group size and the number of groups. The simulation performance results indicate that the proposed algorithm outperforms other mechanisms in terms of routes stability and network density.

Classification of Single-interface Surface Plasmons by Using Complex Differential Diagram (복소차분도표를 이용한 단일경계 표면플라즈몬 모드 이해)

  • Lee, Dong-Jin;Lee, Seung-Gol;O, Beom-Hoan
    • Korean Journal of Optics and Photonics
    • /
    • v.22 no.2
    • /
    • pp.108-113
    • /
    • 2011
  • In this paper, we propose the complex differential diagram to classify surface plasmon waveguide modes with single interface. To date, surface plasmon waveguide modes are classified using the sign change of the group velocity in the dispersion relation that describes the interrelations between the real wavenumber of the propagation direction and the photon energy. The surface plasmon waveguide modes have the wavenumbers of the direction perpendicular to that in which the wave propagates as well as of the propagation direction, so it is necessary to classify the modes using all of these wavenumbers. The complex differential diagram is a graphical representation with variables of the difference between the real component and the imaginary component of the wavenumber. Using this diagram, the specific mode classification is possible, and it is easy to comprehensively analyze the wavenumber as the function of the photon energy.

Fuzzy Tracking Control Based on Stereo Images for Tracking of Moving Robot (이동 로봇 추적을 위한 스테레오 영상기반 퍼지 추적제어)

  • Min, Hyun-Hong;Yoo, Dong-Sang;Kim, Yong-Tae
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.22 no.2
    • /
    • pp.198-204
    • /
    • 2012
  • Tracking and recognition of robots are required for the cooperation task of robots in various environments. In the paper, a tracking control system of moving robot using stereo image processing, code-book model and fuzzy controller is proposed. First, foreground and background images are separated by using code-book model method. A candidate region is selected based on the color information in the separated foreground image and real distance of the robot is estimated from matching process of depth image that is acquired through stereo image processing. The open and close processing of image are applied and labeling according to the size of mobile robot is used to recognize the moving robot effectively. A fuzzy tracking controller using distance information and mobile information by stereo image processing is designed for effective tracking according to the movement velocity of the target robot. The proposed fuzzy tracking control method is verified through tracking experiments of mobile robots with stereo camera.

Estimation Method of the Design Wind Load of Soundproof Wall Using GIS (GIS를 이용한 방음벽의 설계풍하중 산정방법)

  • Lee, Dong-Ho;Choi, Se-Hyu
    • Spatial Information Research
    • /
    • v.23 no.5
    • /
    • pp.75-85
    • /
    • 2015
  • Recently deformed or destroyed of soundproof wall by local winds and typhoon has increased. This research proposed the estimation method of the design wind load of soundproof wall using spatial information analysis based on 1:5,000 digital map and performed comparative analysis with actual application cases. According to the result of quantitative evaluation using GIS, the surface roughness in the downtown area packed with buildings was III and the surface roughness in the suburban district with a relatively small number of buildings was II and the surface roughness in the district packed with open areas and typical farmhouses was I. This shows that the wind load of the soundproof walls reflecting the actual surface conditions was estimated. If the quantitative GIS analysis presented in this study is applied to wind-resistant design of soundproof walls, it is supposed that this will be helpful in more rational wind-resistant design by remedying the existing problem in which the wind load varies depending on designer's subjectivity.

RFID based the SME algorithm for the multi-lane-supproted ETCS (다차선 서비스를 제공하는 자동요금징수시스템을 위한 RFID 기반 SME 알고리즘)

  • Cha, Jin;Jung, Jong-In;Jang, Sang-Woo;Lee, Sang-Sun
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.37 no.1C
    • /
    • pp.8-16
    • /
    • 2012
  • In order for the support of the ETCS (Electronic Toll Collection System) model, which have been operated successfully till now, with multi-lane service, the wireless communication system of the multi-lane-supported ETCS based on RF-DSRC (Radio Frequency - Dedicated Short Range Communication) was used. In this paper, the SME algorithm attaching data flow and form into RFID communication technology was newly suggested to overcome technical problems on RF-DSRC communication system. In addition, in order to verify the SME algorithm, experiments based on ETCS and 900Mhz RFID were carried out. From the result of realization experiment of RFID dependent on the velocity and precision experiment of information inside of RFID, we can see that RFID is detected below 70Km/h and the precision of estimation is more than 90%.