Myo Myint - Academia.edu (original) (raw)

Papers by Myo Myint

I would wish to acknowledge the colleagues at Mandalay Technological University who have contribu... more I would wish to acknowledge the colleagues at Mandalay Technological University who have contributed to the development of this paper.

Cow dung and municipal solid wastes have been selected as cellulolytic bacterial habitants. Nine ... more Cow dung and municipal solid wastes have been selected as cellulolytic bacterial habitants. Nine bacterial strains designated as cd1, cd2, cd3, cd4, mw1, mw2, mw3, mw4 and mw5 were isolated and screened the cellulolytic activity on Berg’s media containing 1%carboxymethyl cellulose (CMC) and cellulose substrate. Six strains showed the halo zone formations which indicate the cellulolytic activity. Among cd strains, cd3 was more effective on cellulolytic activity. On the other hand, mw4 was also potentially more effective. For both carbon sources, they showed the highest halo zone diameters with 30mm and 15mm. The two strains have been studied for quantitative determination of cellulolytic activities by DNS method. CMC and cellulose were used as inducer substrates for cellulase enzyme. In CMC broth, the enzyme producing of cd3 and mw4 showed the reducing sugar formation 1.7mg/ml and 1.677mg/ml when the crude enzyme react with 1% cellulose solution. In cellulose broth, they showed the r...

The author would like to thank to Dr. Myo Myint, Lecturer and Head, Department of Electronic Engi... more The author would like to thank to Dr. Myo Myint, Lecturer and Head, Department of Electronic Engineering, Mandalay Technological University for his kindness, graceful attitude and permission to do this paper. The author would be pleased with her expression of gratitude of her teacher, Dr Hla Myo Htun, Lecturer, Department of Electronic Engineering, Mandalay Technological University, for his valuable advices, helpful suggestions for this paper.

2018 OCEANS - MTS/IEEE Kobe Techno-Oceans (OTO), 2018

This paper presents the 3D pose estimation against turbidity under dark environment by using dual... more This paper presents the 3D pose estimation against turbidity under dark environment by using dual-eye cameras and an active —meaning light emitting— 3D marker for visual-servoing based underwater vehicle. The authors have proposed a 3D-perception based move on sensing (3D-MoS) system using a 3D position and orientation (pose) estimation method with dual-eye cameras that exploits the parallactic nature that enables reliable 3D pose estimation in real-time, named as “Real-time Multi-step Genetic Algorithm (RM-GA).” The active/lighting 3D marker was designed and constructed to improve the 3D pose estimation especially in turbidity and low illumination. In real-time pose estimation, not only recognition but also robustness are important. This paper focus on the robustness of 3D pose recognition performance using dual-eye cameras and 3D marker against turbidity. The experimental results have confirmed that the effectiveness and robustness of the proposed system for the real-time 3D pose ...

Nowadays, autonomous underwater vehicles (AUVs) are essential in applications such as inspection ... more Nowadays, autonomous underwater vehicles (AUVs) are essential in applications such as inspection of underwater structures (e.g., dams and bridges) and underwater cable tracking [1]. Docking operation is very useful not only for battery recharging applications but also other applications such as sleeping under the mother ship, and a new mission downloading [2]. Therefore, there are many studies on underwater docking [2]-[5]. However, a number of challenging issues hinder these applications, which require high accuracy and robustness against disturbances that occur in the underwater environment. To achieve these tasks in underwater vehicles, we have developed a vision-based docking system using stereo vision. In an underwater vehicle with a lighting unit installed on it, especially, dynamic lighting environment addresses challenges when the own lighting system is dominant in a deep sea or during a night operation. Additionally, when an underwater vehicle approaches the sea bottom, wat...

This paper presents a visual-based docking simulation for autonomous underwater vehicle (AUV) und... more This paper presents a visual-based docking simulation for autonomous underwater vehicle (AUV) under unknown environment that offers huge challenges for visual servoing. For relative pose estimation in real-time, model-based recognition approach is applied using two cameras and 3D marker. Real-time Multistep Genetic Algorithm (GA) is utilized to evaluate the gene candidates which represent relative poses until getting the best gene with the most trustful pose. The proposed system is implemented in PC, and the Remotely Operated Vehicle (ROV) is tethered through the cable with 200 m length to receive image information and control signals. We conducted experiments in simulated environment in which light is changing dynamically to confirm whether the proposed system can operate docking task under unknown environment. Experimental results showed that docking operation under unknown lighting environment was completed successfully by only mean of virtual servoing using proposed system follo...

Universal Journal of Physics and Application, 2013

This paper deals with the computational analysis of aerodynamics of space vehicle entering the Ea... more This paper deals with the computational analysis of aerodynamics of space vehicle entering the Earth's atmosphere (from the free-molecular regime to the continuum flow regime) in rarefied gas flow. The use of approximate engineering methods is the most favorable approach to solve problems of spacecraft aerodynamics at the stage of conceptual design. In this paper present the calculation results of aerodynamic characteristics of new generation space vehicle in free molecular, the transitional and continuum regimes by using engineering method. This method may useful to calculate aerodynamic characteristics of new generation space vehicle designs.

2021 28th Conference of Open Innovations Association (FRUCT), 2021

Aiming to the problem of data mining processes building, we present a hierarchical data mining pr... more Aiming to the problem of data mining processes building, we present a hierarchical data mining process ontology. The ontology is constructed based on CRISP-DM framework. Four layers of data mining process are described to solve the complexity of process synthesis. The ontology supports the management of DM processes, that assumes defining steps of the processes and selecting algorithms taking into account the input and the output data. An example of querying on the proposed ontology is presented.

International Journal of Science and Engineering Applications, 2018

Generally, Quadrotor type Unmanned Aerial Vehicles are unstable in nature, so to stabilize it, th... more Generally, Quadrotor type Unmanned Aerial Vehicles are unstable in nature, so to stabilize it, the controller is used. This paper observes the PD controller that make use of UAV to control the adjust of quadrotor UAV even as in the air. The gain parameters of the PD controller, the proportional gain Kp and the derivative gain Kd are apply to be stable and good performance. Unmanned aerial vehicles (UAV) are becoming increasingly common and span a huge range of size and shape. After integrating PD controllers into the systems, quadcopter settling time of roll, pitch and yaw system. Simulations result and comparison of X, Yand Yaw control techniques are presented at the end of this paper. This controller monitors the controlled process variable, and compares it with the reference or set point. The difference between actual and desired value of the process variable, called the error signal. Error is applied as feedback to generate a control action to bring the controlled process variable to the same value as the set point. Control action in which the output is proportional to a linear combination of the input and the time rate of change of input.

Journal of Marine Science and Technology, 2018

This paper presents the verification of the turbidity tolerance of a stereo-vision-based 3D pose ... more This paper presents the verification of the turbidity tolerance of a stereo-vision-based 3D pose estimation system for underwater docking applications. To the best of the authors' knowledge, no studies have yet been conducted on 3D pose (position and orientation) estimation against turbidity for underwater vehicles. Therefore, the effect of turbidity on the 3D pose estimation performance of underwater vehicles and a method of operating under turbid conditions were studied in this work. A 3D pose estimation method using the real-time multi-step genetic algorithm (RM-GA) proposed by the authors in the previous works shows robust pose estimation performance against changing environmental conditions. This paper discusses how and why the RM-GA is well suited to effective 3D pose estimation, even when turbid conditions disturb visual servoing. The experimental results confirm the performance of the proposed 3D pose estimation system under different levels of turbidity. To demonstrate the practical usefulness of the RM-GA, docking experiments were conducted in a turbid pool and a real sea environment to verify the performance and tolerance of the proposed system under turbid conditions. The experimental results verify the robustness of the system against turbidity, presenting a possible solution to a major problem in the field of robotics.

IEEE Journal of Oceanic Engineering, 2018

Recently, many studies have been performed worldwide to extend the persistence of underwater oper... more Recently, many studies have been performed worldwide to extend the persistence of underwater operations by autonomous underwater vehicles. Underwater battery recharging technology is one of the solutions even though challenges still remain. The docking function plays an important role not only in battery recharging but also in other advanced applications, such as intervention. Visual servoing in undersea environments inevitably encounters difficulties in recognizing the environment when captured images are disturbed by noise. This study describes the effective recognition performance and robustness against air bubble disturbances in images captured by a real-time position and orientation (pose) tracking and servoing system using stereo vision for a visual-servoing-type underwater vehicle. The recognition of the vehicle pose based on dynamic images captured by dual video cameras was performed by a real-time multistep genetic algorithm (RM-GA). In previous studies, the docking performance was investigated under the condition that there were no disturbances in the captured images that address image degradation. In this paper, the robustness of the RM-GA against air bubble disturbances was verified through visual servoing and docking experiments in a pool test to confirm that the system can continue to recognize the pose of the 3-D marker and can maintain the desired pose by visual servoing. Then, the effectiveness of the proposed system against real disturbances such as turbidity that may degrade the visibility of the system in the sea was confirmed Manuscript

The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec), 2016

Nowadays, underwater vehicle has become essential tool such applications environmental survey, ca... more Nowadays, underwater vehicle has become essential tool such applications environmental survey, cable or pipeline tracking, unstructured undersea ocean exploration which is hazardous area. We have developed visual based underwater vehicle using dual-eyes cameras and threedimensional marker. In this system,(position and orientation) pose between vehicle and target is estimated by means of 3D model-based recognition utilizing Multi-step GA. This paper analyses the performance of Multi-step GA for 3D recognition for underwater vehicle effectively based on the variations and modification in GA parameters. The recognition accuracy using Multi-step GA is evaluated by using offline full search. The indoor experimental results show that the proposed system can provide promising real-time 3D recognition accuracy.

OCEANS 2015 - MTS/IEEE Washington, 2015

After the Tohoku Earthquake on March 11, 2011, FUKUSHIMA prefecture has been afflicted by disaste... more After the Tohoku Earthquake on March 11, 2011, FUKUSHIMA prefecture has been afflicted by disasters like earthquake, tsunami and nuclear power accident, then decontamination work has been needed to be done in radioactive contamination area. A visual-servo type underwater vehicle system with binocular wide-angle lens has been developed and it has expanded the sphere for surveying submarine resources and decontaminating radiation from mud in dam lake, river, regulation pond, sea in FUKUSHIMA. This paper studies the robustness of visual-servo type underwater vehicle system using three-dimensional (3D) marker under air bubble disturbance on real-time pose (position and orientation) tracking for visual servo. The recognition of vehicle's pose through 3D marker is executed by Genetic Algorithms (GA). The proposed system does not merely calculate the pose information, but can recognize the target pose information through GA while visual servo, because the system utilizes a 3D marker shape and color to recognize the marker. In our previous research, a performance of the system to regulate the vehicle's pose to the relative desired pose against the 3D marker was explored under the condition that there was no disturbance on images. Therefore this paper studies the robustness of the proposed system for air bubble disturbance on the image, aiming at confirming the robustness of the proposed visual servo system. The following results were derived; (1) The proposed system is robust to time-variant target position in zaxis (front-back direction of the vehicle). (2) Although the fitness value of GA is influenced by disturbance, the system can keep recognizing the pose of 3D marker, and (3) tracking by visual servo could be stably kept under the air bubble disturbances.

Transactions of the JSME (in Japanese), 2017

A variety of robots has been studied and developed for undersea exploration. One of the applicati... more A variety of robots has been studied and developed for undersea exploration. One of the applications for undersea exploration is mining of undersea resources such as methane hydrate and rare metal by Autonomous Underwater Vehicle (AUV). To extend active duration time of the robot in the sea, a system through which the AUVs recharge autonomously batteries is a key technology. The authors have confirmed in a pool environment the dual-eye visual servoing system made a pole attached to the vehicle dock into a pipe that simulates recharging station, but the abilities have not been verified in real sea environment. The purpose of this paper is to scrutinize the capability that the visual servoing system can conduct docking operation in real sea, which has disadvantage like impurity deducting visible distance comparing a condition in a pool filled with tap water and disturbances made by waves and currents. The docking has been conducted five times and four docking trials have been successfully completed, and all four succeeded docking data have been presented in detail with behavior analyses of the robot in the sea.

2016 Techno-Ocean (Techno-Ocean), 2016

Genetic algorithm (GA) has been applied for real-time pose estimation in this research because of... more Genetic algorithm (GA) has been applied for real-time pose estimation in this research because of its simplicity, global perspective and repeatable ability. In many of these different situations or problems, optimum selection parameters are a critical factors in the performance of GA. We have developed visual-servo type underwater vehicle using dual-eye camera and 3D marker using real-time pose tracking, named as Real-time Multi-step GA. The relative pose between a vehicle and a 3D-marker can be estimated by Model-based matching method. To recognize the pose of the marker with respect to the vehicle, it is needed to utilize the optimum searching in real-time, and the real-time pose estimation problem can be converted into an optimization problem over a time-varying distribution function with multiple variables. Therefore, analyses the convergence performance of real-time multi-step GA for 3D model-based recognition for underwater vehicle was conducted and reported in this paper. The main aim of this paper is to choose the best parameters for GA that are optimized over population size, selection rate, mutation rate based on their relative fitness value to improve the performance of searching in time domain. The experimental results show that the proposed system effectively improved the searching performance of Real-time multi-step GA for real time pose tracking, having enable an automatic docking of underwater vehicle by dual-eyes visual servoing.

2016 55th Annual Conference of the Society of Instrument and Control Engineers of Japan (SICE), 2016

Nowadays, underwater docking application plays an important role in sea development. This paper s... more Nowadays, underwater docking application plays an important role in sea development. This paper studies visual-servo type docking system for underwater vehicle through real-time pose (position and orientation) tracking with stereo vision. Real-time estimation of vehicle's relative pose to 3D marker whose shape and color is predetermined and known is executed by 3D model-based matching utilizing Genetic Algorithms (GA). In this paper, unidirectional docking station is designed and effective docking strategy is proposed for recharging application of batteries. P controller is applied for visual servoing. Docking experiments were conducted in the sea at Wakayama prefecture, Japan. According to the experimental results, it can be confirmed that docking performance using proposed system is achieved successfully with millimetre level accuracy in recognition and visual servoing.

OCEANS 2016 - Shanghai, 2016

This paper proposes visual-based underwater vehicle docking/homing system under the environment e... more This paper proposes visual-based underwater vehicle docking/homing system under the environment especially simulated for deep sea trial. Instead of measuring absolute position of vehicle using other non-contact sensors, estimation of the robot's relative position and posture (pose) using dual-eyes cameras and 3D target object is proposed. For relative pose estimation, 3D model-based recognition approach is applied because of its real-time effective performance. According to effectiveness, simplicity and repeatable evaluation ability for real-time performance, Genetic Algorithm (GA) is utilized here as a modified form of " Multi-step GA" to evaluate the gene candidates that represent relative poses until getting the best gene with the most trustful pose in dynamic images input by videorate. P controller is used to control the vehicle for the desired pose using real-time images from dual-eyes cameras. Since the underwater environment is complex, this work also addresses to the experiment for deep sea docking operation under changeable lighting environment derived from pose fluctuation of underwater vehicle with two LED-lighting direction altered accordingly that offers huge challenges for visual servoing. As the main contribution for this paper, therefore, we have developed visual servoing using adaptive system for unknown lighting environment. Remotely Operated Vehicle (ROV) is used as a test bed and the experiments are conducted in simulated indoor pool. Experimental results show visual servoing performance under varying lighting conditions and docking performance using proposed system.

2015 IEEE/SICE International Symposium on System Integration (SII), 2015

A visual-servo type remotely operated vehicle (ROV) system with binocular wide-angle lens was dev... more A visual-servo type remotely operated vehicle (ROV) system with binocular wide-angle lens was developed to survey submarine resources, decontaminate radiation from mud in dam lake and so on. This paper explores the experiments on regulator performance and underwater docking of the robot system utilizing Genetic Algorithm (GA) for real-time recognition of the robot's relative pose (position and posture) through 3D marker. The visual servoing performances have been verified as follows; (1) The stability performances of the proposed regulator system have been evaluated by exerting abrupt distrubane force while the ROV is controlled by visual servoing, (2) The proposed system can track time-variant desired target position in z-axis (front-back direction of the robot), (3) The underwater docking can be completed by switching visual servoing and docking modes based on the error threshold, and by giving time-varying desired target pose to the controller as a desired pose.

Journal of the Asia Pacific Economy, 2014