• Title/Summary/Keyword: Particle Systems

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Localization of Mobile Robot Using SURF and Particle Filter (SURF와 Particle filter를 이용한 이동 로봇의 위치 추정)

  • Mun, Hyun-Su;Joo, Young-Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.4
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    • pp.586-591
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    • 2010
  • In this paper, we propose the localization method of mobile robot using SURF(Speeded-Up Robust Features) and Particle filter. The proposed method is as follows: First, we seek the Landmark from the obtained image using SURF in order to find the first rigorous position of mobile robot. Second, we obtain the distance from obstacles using ultrasonic sensors in order to create the relative position of mobile robot. And then, we estimate the localization of mobile robot using Particle filter about movement of mobile robot. Finally, we show the feasibility of the proposed method through some experiments.

Terrain-referenced Underwater Navigation using Rao-Blackwellized Particle Filter (라오-블랙웰라이즈드 입자필터를 이용한 지형참조 수중항법)

  • Kim, Taeyun;Kim, Jinwhan;Choi, Hyun-Taek
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.8
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    • pp.682-687
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    • 2013
  • Navigation is a crucial capability for all types of manned or unmanned vehicles. However, vehicle navigation in underwater environments still remains a challenging problem since GPS signals for position fixes are not available in the water. Terrain-referenced underwater navigation is an alternative navigation technique that utilizes geometric information of the subsea terrain to correct drift errors due to dead-reckoning or inertial navigation. Terrain-referenced navigation requires the description of an undulating terrain surface as a mathematical function or table, which often leads to a highly nonlinear estimation problem. Recently, PFs (Particle Filters), which do not require any restrictive assumptions about the system dynamics and uncertainty distributions, have been widely used for nonlinear filtering applications. However, PF has considerable computational requirements which used to limit its applicability to problems of relatively low state dimensions. This study proposes the use of a Rao-Blackwellized particle filter that is computationally more efficient than the standard PF for terrain-referenced underwater navigation involving a moderate number of states, and its performance is compared with that of the extended Kalman filter algorithm. The validity and feasibility of the proposed algorithm is demonstrated through numerical simulations.

Changes in Shear Strength of Bottom ash through the Particle Breakage (입자파쇄에 따른 Bottom ash의 전단강도 변화)

  • Yun, Tae-Kang;Son, Young-Hwan;Park, Jae-Sung;Noh, Soo-Kack;Bong, Tae-ho;Kim, Dong-Geun
    • Journal of The Korean Society of Agricultural Engineers
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    • v.57 no.6
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    • pp.99-105
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    • 2015
  • Bottom ash and fly ash are by-product from thermoelectric power plants. Fly ash is recycled to various field. However, though an output of bottom ash have increased each year, most of them is reclaimed in ash landfill. It is necessary to find a solution that bottom ash is recycled economically and know characteristics of bottom ash to recycle. It is goal to investigate engineering properties of bottom ash, especially the particle breakage, to recycle that. Bottom ash was crushed by impact method according to compaction energy and then compared with or original sample and crushed it in terms of particle size distribution and characteristics of strength. In result, after crushed it, particle finer was increased, especially 2~0.85 mm size, than original. It was displayed a tendency that internal friction of crushed sample was decreased but cohesion of it was not. Therefore, it is important to investigate the engineering properties of bottom ash in terms of the particle breakage to use construction materials for various field.

Investigation of the Performance Characteristics of an In-Situ Particle Monitor at Low Pressures Using Aerodynamic Lenses (저압상태에서 공기역학적 렌즈를 이용한 In-Situ Particle Monitor의 성능특성 분석)

  • Bae, Gwi-Nam
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.10
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    • pp.1359-1367
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    • 2000
  • In-situ particle monitors(ISPMs) are widely used for monitoring contaminant particles in vacuum-based semiconductor manufacturing equipment. In the present research, the performance of a Particle Measuring Systems(PMS) Vaculaz-2 ISPM at low pressures has been studied. We generated the uniform sized methylene blue particle beams using three identical aerodynamic lenses in the center of the vacuum line, and measured the detection efficiency of the ISPM. The effects of particle size, particle concentration, mass flow rate, system pressure, and arrangement of aerodynamic lenses on the detection efficiency of the ISPM were examined. Results show that the detection efficiency of the ISPM greatly depends on the mass flow rate, and the particle Stokes number. We also found that the optimum Stokes number ranges from 0.4 to 1.9 for the experimental conditions.

Performance Characteristics of In-Situ Particle Monitors at Sub-Atmospheric Pressure (감압상태에서의 In-Situ Particle Monitor의 성능특성)

  • Bae, Gwi-Nam
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.11
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    • pp.1564-1570
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    • 1998
  • In-situ particle monitors(ISPMs) are widely used for monitoring contaminant particles in vacuum-based semiconductor manufacturing equipment. In the present research, the performance of a Particle Measuring Systems(PMS) Vaculaz-2 ISPM at subatmospheric pressures has been studied. We created uniform upstream conditions of particle concentration and measured the detection efficiency, the lower detection limit, and the size response of the ISPM using uniform sized methylene blue aerosol particles. The effect of particle size, particle velocity, particle concentration, and system pressure on the detection efficiency was examined. Results show that the detection efficiency of the ISPM decreases with decreasing chamber pressure, and with increasing mass flow rate. The lower detection limit of the ISPM, determined at 50 % of the measured maximum detection efficiency, was found to be about $0.15{\sim}0.2{\mu}m$, which is similar to the minimum detectable size of $0.17{\mu}$ given by the manufacturer.

Rule-based Hybrid Discretization of Discrete Particle Swarm Optimization for Optimal PV System Allocation (PV 시스템의 최적 배치 문제를 위한 이산 PSO에서의 규칙 기반 하이브리드 이산화)

  • Song, Hwa-Chang;Ko, Jae-Hwan;Choi, Byoung-Wook
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.6
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    • pp.792-797
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    • 2011
  • This paper discusses the application of a hybrid discretiziation method for the discretization procedure that needs to be included in discrete particle swarm optimization (DPSO) for the problem of allocating PV (photovoltaic) systems onto distribution power systems. For this purpose, this paper proposes a rule-based expert system considering the objective function value and its optimizing speed as the input parameters and applied it to the PV allocation problem including discrete decision variables. For multi-level discretization, this paper adopts a hybrid method combined with a simple rounding and sigmoid funtion based 3-step and 5-step quantization methods, and the application of the rule based expert system proposing the adequate discretization method at each PSO iteration so that the DPSO with the hybrid discretization can provide better performance than the previous DPSO.

Development of a Real-time Monitoring Device for Measuring Particulate Matter

  • Kim, Dae Seong;Cho, Young Kuk;Yoon, Young Hun
    • Particle and aerosol research
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    • v.10 no.1
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    • pp.1-8
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    • 2014
  • In this study, we have developed a real-time monitoring device for measuring $PM_{10/2.5/1}$ of ambient aerosol particles. The real-time PM (Particulate Matter) monitor was based on the light scattering method and had 16 channels in particle size. The laboratory and field tests were carried out to evaluate the performance of the PM monitor developed. Arizona Road Dust particles ranging from diameter of 0.1 to $20{\mu}m$ were generated as test particles in the laboratory test. The field test was carried out at the Seoul Meteorological Observatory. We can obtain the particle size and number concentration (particle size distribution) only from the real-time PM monitor developed. Therefore, the average density of aerosol particles was used to obtain the PM data from the particle size distribution. The $PM_{10/2.5/1}$ results of the PM monitor were compared with the data of the Grimm Dust Monitor (Model 1.108) and a beta ray gauge (Thermo Fisher Scientific). As a result, it was shown that the $PM_{10/2.5/1}$ results obtained by the real-time PM monitor agreed well with the data of the reference devices, and overall, the real-time PM monitor could be used as a PM monitoring device for real-time monitoring of the ambient particles.

Photovoltaic System Allocation Using Discrete Particle Swarm Optimization with Multi-level Quantization

  • Song, Hwa-Chang;Diolata, Ryan;Joo, Young-Hoon
    • Journal of Electrical Engineering and Technology
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    • v.4 no.2
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    • pp.185-193
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    • 2009
  • This paper presents a methodology for photovoltaic (PV) system allocation in distribution systems using a discrete particle swarm optimization (DPSO). The PV allocation problem is in the category of mixed integer nonlinear programming and its formulation may include multi-valued dis-crete variables. Thus, the PSO requires a scheme to deal with multi-valued discrete variables. This paper introduces a novel multi-level quantization scheme using a sigmoid function for discrete particle swarm optimization. The technique is employed to a standard PSO architecture; the same velocity update equation as in continuous versions of PSO is used but the particle's positions are updated in an alternative manner. The set of multi-level quantization is defined as integer multiples of powers-of-two terms to efficiently approximate the sigmoid function in transforming a particle's position into discrete values. A comparison with a genetic algorithm (GA) is performed to verify the quality of the solutions obtained.

Combined nano-particle drug delivery and physiotherapy in treatment of common injuries in dance-sport

  • Weixin Dong;Gang Lu;Yangling Jiang;Fan Zhou;Xia Liu;Chunxia Lu
    • Advances in nano research
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    • v.15 no.3
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    • pp.225-237
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    • 2023
  • Combination of novel technologies with traditional physiotherapy in rehabilitation in injured athletes have shown to provide improved time of recovery. In specific, nanodrugs delivery systems are widely utilized as a counterpart to the physiotherapy in injuries in sports. In the present study, we focus on the common injuries in dance-sports, their recovery and the effect combination of nano-particle drug delivery with the physiotherapy practices. In this regard, a comprehensive review on the common injuries in dance sport is provided. Moreover, the researches on the effectiveness of the nano-particle drug delivery in therapy of such injuries and in similar cases are provided. The possibility of using combination of nano-particle drug delivery and physiotherapy is discussed in detail. Finally, using artificial intelligence methods, predictions on the recovery time and after-treatment side-effects is investigated. Artificial Neural Network (ANN) predictions suggested that using nano-particle drug delivery systems along with physiotherapy practices could provide shortened treatment time to recovery in comparison to conventional drugs. Moreover, the post-recover effects are less than the conventional methods.

Development, validation and implementation of multiple radioactive particle tracking technique

  • Mehul S. Vesvikar;Thaar M. Aljuwaya;Mahmoud M. Taha;Muthanna H. Al-Dahhan
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.4213-4227
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    • 2023
  • Computer Automated Radioactive Particle Tracking (CARPT) technique has been successfully utilized to measure the velocity profiles and mixing parameters in different multiphase flow systems where a single radioactive tracer is used to track the tagged phase. However, many industrial processes use a wide range of particles with different physical properties where solid particles could vary in size, shape and density. For application in such systems, the capability of current single tracer CARPT can be advanced to track more than one particle simultaneously. Tracking multiple particles will thus enable to track the motion of particles of different size shape and density, determine segregation of particles and probing particle interactions. In this work, a newly developed Multiple Radioactive Particle Tracking technique (M-RPT) used to track two different radioactive tracers is demonstrated. The M-RPT electronics was developed that can differentiate between gamma counts obtained from the different radioactive tracers on the basis of their gamma energy peak. The M-RPT technique was validated by tracking two stationary and moving particles (Sc-46 and Co-60) simultaneously. Finally, M-RPT was successfully implemented to track two phases, solid and liquid, simultaneously in three phase slurry bubble column reactors.