This paper proposes a local search algorithm to find the egalitarian and the sex-equal stable mat... more This paper proposes a local search algorithm to find the egalitarian and the sex-equal stable matchings in the stable marriage problem. Based on the dominance relation of stable matchings from the men's point of view, our approach discovers the egalitarian and the sex-equal stable matchings from the man-optimal stable matching. By employing a breakmarriage strategy to find stable neighbor matchings of the current stable matching and moving to the best neighbor matching, our local search finds the solutions while moving towards the woman-optimal stable matching. Simulations show that our proposed algorithm is efficient for the stable marriage problem.
2012 8th International Conference on Information Science and Digital Content Technology, Jun 26, 2012
This paper presents an online complete coverage algorithm for cleaning robots based on boustrophe... more This paper presents an online complete coverage algorithm for cleaning robots based on boustrophedon motions combined with A* search algorithm. In our approach, while performing a boustrophedon motion to cover an unvisited area in the workspace, the robot detects and stores backtracking points. To execute the next boustrophedon motion, A* search is employed as a backtracking mechanism which guides the robot to the nearest backtracking point. Experimental results prove that the proposed algorithm ensures the complete coverage of the workspace in the finite moving steps of the robot. Furthermore, our proposed approach is efficient in terms of the covered path length and the number of boustrophedon motions.
Journal of Engineering Physics and Thermophysics, 1993
The effect of an external field on the spatial distribution of particles emerging from a cylindri... more The effect of an external field on the spatial distribution of particles emerging from a cylindrical channel has been investigated with adsorption and surface diffusion of particles on the channel walls taken into consideration.
This paper presents a new approach to solve the pursuit problem based on a univector field method... more This paper presents a new approach to solve the pursuit problem based on a univector field method. In our proposed method, a set of eight agents works together instantaneously to find suitable moving directions and follow the univector field to pursue and capture a prey agent by surrounding it from eight directions in an infinite grid-world. In addition, a set of strategies is proposed to make the pursuit problem more realistic in the real world environment. This is a general approach, and it can be extended for an environment that contains static or moving obstacles. Experimental results show that our proposed algorithm is effective for the pursuit problem.
2013 13th International Conference on Control, Automation and Systems (ICCAS 2013), 2013
This paper presents a novel approach to deal with the online complete coverage problem for a team... more This paper presents a novel approach to deal with the online complete coverage problem for a team of robots in unknown environments. In our approach each robot covers an unvisited region using a single boustrophedon motion until a robot reaches an ending point, which is surrounded by covered positions or obstacles. At the ending point the robot detects backtracking points based on the accumulated knowledge, plans the shortest backtracking path to the next starting point based on the proposed Theta* with multi-goals. Then, it follows the planed path to the next starting point to cover the next unvisited region. The robot team finishes the coverage task when no backtracking point is detected. Computer simulations show that our proposed approach is efficient for the complete coverage task of a robot team in terms of the coverage rate and the coverage path length.
Page 1. Simulation-Based Evaluations of Reinforcement Learning Algorithms for Autonomous Mobile R... more Page 1. Simulation-Based Evaluations of Reinforcement Learning Algorithms for Autonomous Mobile Robot Path Planning Hoang Huu Viet, Phyo Htet Kyaw and TaeChoong Chung Abstract This work aims to evaluate the efficiency ...
This paper presents a novel algorithm to improve the efficiency of path planning for autonomous m... more This paper presents a novel algorithm to improve the efficiency of path planning for autonomous mobile robots. In an obstacle-free environment, the path planning of a robot is attained by following the vector direction from its current position to the goal position. In an obstacle environment, while following the vector direction, a robot has to avoid obstacles by rotating the moving direction. To accomplish the obstacle avoidance task for the mobile robot, the Q(λ) algorithm is employed to train the robot to learn suitable moving directions. Experimental results show that the proposed algorithm is soundness and completeness with a fast learning rate in the large environment of states and obstacles.
Proceedings of the 2010 Symposium on Information and Communication Technology - SoICT '10, 2010
Page 1. Ngo Van Manh Pham Quoc Vinh Hoang Anh Viet Huynh Quyet Thang Hanoi University of Technolo... more Page 1. Ngo Van Manh Pham Quoc Vinh Hoang Anh Viet Huynh Quyet Thang Hanoi University of Technology Hanoi University of Technology Hanoi University of Technology Hanoi University of Technology Address: P.327, C1 ...
2011 International Conference on Electromagnetics in Advanced Applications, 2011
A printed MIMO antenna with extremely wide-band (EWB) for multi-band wireless applications has be... more A printed MIMO antenna with extremely wide-band (EWB) for multi-band wireless applications has been proposed and analyzed in this paper. The designed antenna satisfies the voltage standing wave ratio (VSWR) requirement of less than 2.0 in an extremely wide frequency band ranging from 2.7 GHz to 20 GHz. To enhance the isolation coefficient in MIMO antenna, two parallel strips are
In this note we discuss some properties of torsion points on elliptic curves dened over small ext... more In this note we discuss some properties of torsion points on elliptic curves dened over small extensions of Q. As an application, we give a new proof of a theorem of Olson. AMS Mathematics Subject Classication (2000): Primary 11G05, Sec- ondary 11G07
SUMMARYWe present an algorithm for offsetting the workspace obstacles of a circular robot. Our me... more SUMMARYWe present an algorithm for offsetting the workspace obstacles of a circular robot. Our method has two major steps: It finds the raw offset curve for both lines and circular arcs, and then removes the global invalid loops to find the final offset. To generate the raw offset curve and remove global invalid loops,O(n)andO((n+k)logm) computational times are needed respectively, wherenis the number of vertices in the original polygon,kis the number of self-intersections andmis the number of segments in the raw offset curve, wherem≤n. Any local invalid loops are removed before generating the raw offset curve by invoking a pair-wise intersection detection test (PIDT). In the PIDT, two intersecting entities are checked immediately after they are computed, and if the test is positive, portions of the intersecting segments are removed. Our method works for conventional polygons as well as the polygons that contain circular arcs. Our algorithm is simple and very fast, as each sub-proce...
Reinforcement learning (RL) is a popular method for solving the path planning problem of autonomo... more Reinforcement learning (RL) is a popular method for solving the path planning problem of autonomous mobile robots in unknown environments. However, the primary difficulty faced by learning robots using the RL method is that they learn too slowly in obstacle-dense environments. To more efficiently solve the path planning problem of autonomous mobile robots in such environments, this paper presents a novel approach in which the robot’s learning process is divided into two phases. The first one is to accelerate the learning process for obtaining an optimal policy by developing the well-known Dyna-Q algorithm that trains the robot in learning actions for avoiding obstacles when following the vector direction. In this phase, the robot’s position is represented as a uniform grid. At each time step, the robot performs an action to move to one of its eight adjacent cells, so the path obtained from the optimal policy may be longer than the true shortest path. The second one is to train the robot in learning a collision-free smooth path for decreasing the number of the heading changes of the robot. The simulation results show that the proposed approach is efficient for the path planning problem of autonomous mobile robots in unknown environments with dense obstacles.
In the present paper the governing equations for dynamical analysis of corrugated cross-ply lamin... more In the present paper the governing equations for dynamical analysis of corrugated cross-ply laminated composite plates in the form of a sin wave are developed based on the Kirchoff-Love's theory and the extension of Seydel's technique. The problems of natural vibration ...
This paper proposes a local search algorithm to find the egalitarian and the sex-equal stable mat... more This paper proposes a local search algorithm to find the egalitarian and the sex-equal stable matchings in the stable marriage problem. Based on the dominance relation of stable matchings from the men's point of view, our approach discovers the egalitarian and the sex-equal stable matchings from the man-optimal stable matching. By employing a breakmarriage strategy to find stable neighbor matchings of the current stable matching and moving to the best neighbor matching, our local search finds the solutions while moving towards the woman-optimal stable matching. Simulations show that our proposed algorithm is efficient for the stable marriage problem.
2012 8th International Conference on Information Science and Digital Content Technology, Jun 26, 2012
This paper presents an online complete coverage algorithm for cleaning robots based on boustrophe... more This paper presents an online complete coverage algorithm for cleaning robots based on boustrophedon motions combined with A* search algorithm. In our approach, while performing a boustrophedon motion to cover an unvisited area in the workspace, the robot detects and stores backtracking points. To execute the next boustrophedon motion, A* search is employed as a backtracking mechanism which guides the robot to the nearest backtracking point. Experimental results prove that the proposed algorithm ensures the complete coverage of the workspace in the finite moving steps of the robot. Furthermore, our proposed approach is efficient in terms of the covered path length and the number of boustrophedon motions.
Journal of Engineering Physics and Thermophysics, 1993
The effect of an external field on the spatial distribution of particles emerging from a cylindri... more The effect of an external field on the spatial distribution of particles emerging from a cylindrical channel has been investigated with adsorption and surface diffusion of particles on the channel walls taken into consideration.
This paper presents a new approach to solve the pursuit problem based on a univector field method... more This paper presents a new approach to solve the pursuit problem based on a univector field method. In our proposed method, a set of eight agents works together instantaneously to find suitable moving directions and follow the univector field to pursue and capture a prey agent by surrounding it from eight directions in an infinite grid-world. In addition, a set of strategies is proposed to make the pursuit problem more realistic in the real world environment. This is a general approach, and it can be extended for an environment that contains static or moving obstacles. Experimental results show that our proposed algorithm is effective for the pursuit problem.
2013 13th International Conference on Control, Automation and Systems (ICCAS 2013), 2013
This paper presents a novel approach to deal with the online complete coverage problem for a team... more This paper presents a novel approach to deal with the online complete coverage problem for a team of robots in unknown environments. In our approach each robot covers an unvisited region using a single boustrophedon motion until a robot reaches an ending point, which is surrounded by covered positions or obstacles. At the ending point the robot detects backtracking points based on the accumulated knowledge, plans the shortest backtracking path to the next starting point based on the proposed Theta* with multi-goals. Then, it follows the planed path to the next starting point to cover the next unvisited region. The robot team finishes the coverage task when no backtracking point is detected. Computer simulations show that our proposed approach is efficient for the complete coverage task of a robot team in terms of the coverage rate and the coverage path length.
Page 1. Simulation-Based Evaluations of Reinforcement Learning Algorithms for Autonomous Mobile R... more Page 1. Simulation-Based Evaluations of Reinforcement Learning Algorithms for Autonomous Mobile Robot Path Planning Hoang Huu Viet, Phyo Htet Kyaw and TaeChoong Chung Abstract This work aims to evaluate the efficiency ...
This paper presents a novel algorithm to improve the efficiency of path planning for autonomous m... more This paper presents a novel algorithm to improve the efficiency of path planning for autonomous mobile robots. In an obstacle-free environment, the path planning of a robot is attained by following the vector direction from its current position to the goal position. In an obstacle environment, while following the vector direction, a robot has to avoid obstacles by rotating the moving direction. To accomplish the obstacle avoidance task for the mobile robot, the Q(λ) algorithm is employed to train the robot to learn suitable moving directions. Experimental results show that the proposed algorithm is soundness and completeness with a fast learning rate in the large environment of states and obstacles.
Proceedings of the 2010 Symposium on Information and Communication Technology - SoICT '10, 2010
Page 1. Ngo Van Manh Pham Quoc Vinh Hoang Anh Viet Huynh Quyet Thang Hanoi University of Technolo... more Page 1. Ngo Van Manh Pham Quoc Vinh Hoang Anh Viet Huynh Quyet Thang Hanoi University of Technology Hanoi University of Technology Hanoi University of Technology Hanoi University of Technology Address: P.327, C1 ...
2011 International Conference on Electromagnetics in Advanced Applications, 2011
A printed MIMO antenna with extremely wide-band (EWB) for multi-band wireless applications has be... more A printed MIMO antenna with extremely wide-band (EWB) for multi-band wireless applications has been proposed and analyzed in this paper. The designed antenna satisfies the voltage standing wave ratio (VSWR) requirement of less than 2.0 in an extremely wide frequency band ranging from 2.7 GHz to 20 GHz. To enhance the isolation coefficient in MIMO antenna, two parallel strips are
In this note we discuss some properties of torsion points on elliptic curves dened over small ext... more In this note we discuss some properties of torsion points on elliptic curves dened over small extensions of Q. As an application, we give a new proof of a theorem of Olson. AMS Mathematics Subject Classication (2000): Primary 11G05, Sec- ondary 11G07
SUMMARYWe present an algorithm for offsetting the workspace obstacles of a circular robot. Our me... more SUMMARYWe present an algorithm for offsetting the workspace obstacles of a circular robot. Our method has two major steps: It finds the raw offset curve for both lines and circular arcs, and then removes the global invalid loops to find the final offset. To generate the raw offset curve and remove global invalid loops,O(n)andO((n+k)logm) computational times are needed respectively, wherenis the number of vertices in the original polygon,kis the number of self-intersections andmis the number of segments in the raw offset curve, wherem≤n. Any local invalid loops are removed before generating the raw offset curve by invoking a pair-wise intersection detection test (PIDT). In the PIDT, two intersecting entities are checked immediately after they are computed, and if the test is positive, portions of the intersecting segments are removed. Our method works for conventional polygons as well as the polygons that contain circular arcs. Our algorithm is simple and very fast, as each sub-proce...
Reinforcement learning (RL) is a popular method for solving the path planning problem of autonomo... more Reinforcement learning (RL) is a popular method for solving the path planning problem of autonomous mobile robots in unknown environments. However, the primary difficulty faced by learning robots using the RL method is that they learn too slowly in obstacle-dense environments. To more efficiently solve the path planning problem of autonomous mobile robots in such environments, this paper presents a novel approach in which the robot’s learning process is divided into two phases. The first one is to accelerate the learning process for obtaining an optimal policy by developing the well-known Dyna-Q algorithm that trains the robot in learning actions for avoiding obstacles when following the vector direction. In this phase, the robot’s position is represented as a uniform grid. At each time step, the robot performs an action to move to one of its eight adjacent cells, so the path obtained from the optimal policy may be longer than the true shortest path. The second one is to train the robot in learning a collision-free smooth path for decreasing the number of the heading changes of the robot. The simulation results show that the proposed approach is efficient for the path planning problem of autonomous mobile robots in unknown environments with dense obstacles.
In the present paper the governing equations for dynamical analysis of corrugated cross-ply lamin... more In the present paper the governing equations for dynamical analysis of corrugated cross-ply laminated composite plates in the form of a sin wave are developed based on the Kirchoff-Love's theory and the extension of Seydel's technique. The problems of natural vibration ...
Uploads
Papers