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Autonomous Intelligent Systems 2021年第1期1卷 13-31页

作者： bijoy kghosh Bhagya Athukorallage Department of Mathematics and Statistics Texas Tech UniversityLubbockTexas 79409-1042USA School of Automation Engineering University of Electronic Science and Technology of ChinaChengduSichuan 610054China

Over the past several years,we have been studying the problem of optimally rotating a rigid sphere about its center,where the rotation is actuated by a triplet of external torques acting on the *** control objective is to repeatedly direct a suitable radial vector,called the gaze vector,towards a stationary point target in R^(3).The orientation of the sphere is constrained to lie in a suitable submanifold of SO(3).Historically,the constrained rotational movements were studied by physiologists in the nineteenth century,interested in eye and head *** this paper we revisit the gaze control problem,where two visual sensors,are tasked to simultaneously stare at a point target in the visual *** target position changes discretely and the problem we consider is how to reorient the gaze directions of the sensors,along the optimal pathway of the human eyes,to the new location of the *** is done by first solving an optimal control problem on the human binocular ***,we use these optimal control and show that a pan-tilt system can be controlled to follow the gaze trajectory of the human eye requiring a nonlinear static feedback of the pan and tilt angles and their *** problem formulation uses a new Riemannian geometric description of the orientation *** paper also introduces a new,pyramid based interpolation method,to implement the optimal controller.

关键词： Binocular vision Riemannian geometry Optimal control Pyramid based interpolation Bio-Mimetic Pan-Tilt rotation

Modeling of hydrodynamics in a bubbling fluidized-bed gasifier and evaluation of the inter-phase gas exchange rate under different operating conditions

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Particuology 2016年第2期14卷 151-158页

作者： bijoy Das Amitava Datta Development Consultants Pvt. Ltd Salt Lake City Kolkata 700 091 India Department of Power Engineering Jadavpur University Salt Lake Campus Kolkata 700 098 India

A fluid dynamic model of a bubbling fluidized-bed coal gasifier is presented considering two-phase theory of fluidization. The effects of the gasifier temperature and bed particle size on the hydrodynamic char- acteristics of both the bubble and emulsion phases of the gasifier bed are studied. The bubble diameter, bubble velocity, and bubble area fraction are evaluated for the bubble phase, whereas the gas velocity and porosity are studied for the emulsion phase, along the height of the bed. Finally, the rate of inter-phase gas exchange from the emulsion phase to bubble phase is calculated under different operating conditions.

关键词： Bubbling fluidized bed Gasifier Gas exchange rate Bubble Emulsion

Excess Diffusion of a Driven Colloidal Particle in a Convection Array

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Chinese Physics Letters 2021年第4期38卷 17-21页

作者： Qingqing Yin Yunyun Li Fabio Marchesoni Debajyoti Debnath Pulak kghosh Center for Phononics and Thermal Energy Science Shanghai Key Laboratory of Special Artificial Microstructure Materials and TechnologySchool of Physics Science and EngineeringTongji UniversityShanghai 200092China Dipartimento di Fisica Universitàdi CamerinoI-62032 CamerinoItaly Department of Chemistry Presidency UniversityKolkataIndia

We numerically investigate the transport of a passive colloidal particle in a periodic array of planar counterrotating convection rolls,at high Peclet *** is shown that an external bias,oriented parallel to the array,produces a huge excess diffusion peak,in cases where bias and advection drag become *** effect is not restricted to one-dimensional convection geometries,and occurs independently of the array’s boundary conditions.

关键词： conditions. rotating Diffusion

Minimum energy optimal external torque control of human binocular vision

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Control Theory and Technology 2020年第4期18卷 431-458页

作者： bijoy K.Ghosh Bhagya Athukorallage Department of Mathematics and Statistics Texas Tech UniversityLubbockTX 79409-1042USA School of Automation Engineering University of Electronic Science and Technology of ChinaChengduSichuan 610054China

In this paper,we consider eyes from the human binocular system,that simultaneously gaze on stationary point targets in space,while optimalal skipping from one target to the next,by rotaing their individual gaze *** head is assume fixed on the torso and the rotaing gaze direction of the two eyes are assumed restricted to pass through a point in the visual *** is further assumed that,individullly the rotations of the two eyes satisfy the well known Listing's *** formulate and study acombined optimal gaze rotation for the two eyes,by constructing a single Riemanmian metric,on the asociaced parameter *** goal is to optimally rotate so that the convergent gaze changes between two pre-specified target points in a finite time interval[0,1].The cost function we choose is the total energy,measured by the L2?norm,of the six extenal torques on the binocular *** torque functions are synthesized by solving an associated*two-point boundary value *** paper demonstrates,via simulation,the shape of the optimal gaze trajectory of the focused point of the bin-ocular *** Euclidean distance between the initial and the final point is compared to the arc:length of the optimal *** consumed *** computed for diferent eye movement chores and discussed in the *** simulation we observe that certain eye movement maneuvers are energy fficicnt and demonstrate that the optimal external torque is a linear function in *** also explore and conclude that spitting an arbitry opimal eye movement into optimal vergence and version components is not energy fficient although this is how the human oculomotor control seems to *** gaze tajectories and opimal extermal torque functions reported in this paper is new.

关键词： Binocular vision Riemamian gcometry Optimal control Human eye movement

A transverse local feedback linearization approach to human head movement control

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Control Theory and Technology 2017年第4期15卷 288-300页

作者： Takafumi Oki bijoy K. Ghosh 1. Department of Mathematics and Statistics Texas Tech University Lubbock Texas 79409-1042 U.S.A.

In the mid-nineteenth century, Donders had proposed that for every human head rotating away from the primary pointing direction, the rotational vectors in the direction of the corresponding axes of rotation, is restricted to lie on a surface. Donders＇ intuition was that under such a restriction, the head orientation would be a function of its pointing direction. In this paper, we revisit Donders＇ Law and show that indeed the proposed intuition is true for a restricted class of head-orientations satisfying a class of quadratic Donders＇ surfaces, if the head points to a suitable neighborhood of the frontal pointing direction. Moreover, on a suitably chosen subspace of the 3D rotation group SO（3）, we describe a head movement dynamical system with input control signals that are the three external torques on the head provided by muscles. Three output signals are also suitably chosen as follows. Two of the output signals are coordinates of the frontal pointing direction. The third signal measures deviation of the state vector from the Donders＇ surface. We claim that the square system is locally feedback linearizable on the subspace chosen, and the linear dynamics is decomposed into parts, transverse and tangential to the Donders＇ surface. We demonstrate our approach by synthesizing a tracking and path-following controller. Additionally, for different choices of the Donders＇ surface parameters, head gaits are visualized by simulating different movement patterns of the head-top vector, as the head-pointing vector rotates around a circle.

关键词： Head movement Donders' surface transverse feedback linearization Fick-Gimbal

Waste plastics-to-fuel using fly ash catalyst

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Waste Disposal and Sustainable Energy 2021年第1期3卷 13-30页

作者： bijoy Kumar Mondal Falguni Guha MdNurul Abser Department of Chemistry Jahangirnagar UniversitySavarDhakaBangladesh Department of Biochemistry and Microbiology North South UniversityDhakaBangladesh

Suitable disposal pathways of waste plastics and coal fly ash have yet not been established which is a matter of great envi-ronmental *** low-density polyethylene(LDPE)and high-density polyethylene(HDPE)were degraded using a semi-batch reactor along with acid or alkali modified fly ash *** high yield of liquid fuel product(about 87.24 wt%)was achieved for low-density polyethylene at a polymer and catalyst ratio of 25 w/*** 96%conversion was found with very few amount of gaseous *** of the waste plastics were degraded at 400-450℃.The liquid products were analyzed using Fourier-transform infrared spectroscopy(FTIR),nuclear magnetic resonance(^(1)H,^(13)C,and DEPT-135 NMR),and gas chromatography-mass spectrometry(GC-MS).Fly ash is an efficient catalyst to degrade waste plastic into light weight liquid(gasoline and kerosene)*** NMR results accompanied by GC-MS data ensure that obtained fuels contain both aliphatic(saturated and unsaturated)and aromatic *** plastic-to-fuel technology should be commercialized owing to be profitable and eco-friendly.

关键词： Solid waste Catalytic pyrolysis Liquid fuels

Data-driven containment control of discrete-time multi-agent systems via value iteration

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Science China(Information Sciences) 2020年第8期63卷 254-256页

作者： Zhinan PENG Jiangping HU bijoy Kumar GHOSH School of Automation Engineering University of Electronic Science and Technology of China Department of Mathematics and Statistics Texas Tech University

Dear editor,We consider a containment control problem for a linear discrete-time (DT) multi-agent system via reinforcement learning. Containment control(CC) of multi-agent networks has received extensive attention in the control community in recent years [1–4]. CC is motivated by natural phenomena and has potential and vital applications in practical engineering. For example, one applica-

关键词： containment control multi-agent systems distributed control linear systems optimal control

Special issue on emerging challenges in multi-agent sensing,control and optimization

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Control Theory and Technology 2020年第4期18卷 337-338页

作者： bijoy Kumar Ghosh Jiangping Hu Xiaoming Hu Texas Tech University LubbockUSA University of Electronic Science and Technology of China Chengdu China 3 KTH Royal Institute of TechnologyStockholmSweden

Up to now,a large number of theoretical achievements and application scenarios have been obtained in sensing,control and optimization of multi-agent ***,challenges are still emerging from the rapid development of artificial intelligence and urgent need for distributed *** aim of the special issue is to present in a systematic way some new results in the fields of distributed sensing,control and optimization of cyber-physical systems,particularly in resource allocation,machine learning,observer and filtering,consensus and constrained control.

关键词： agent artificial optimization

Safe formation control of multiple unmanned aerial vehicles:control design and safety-stability analysis

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Control Theory and Technology 2024年第3期22卷 442-454页

作者： Haoqi Li Jiangping Hu Qingrui Zhou bijoy K.Ghosh School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313000ZhejiangChina Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China Department of Mathematics and Statistics Texas Tech UniversityLubbockTX 79409-1042USA

Both safety and stability are primary performance criteria for multi-unmanned aerial vehicle(multi-UAV)systems in many coordination *** approaches often consider safety and stability *** is necessary and urgent to develop a safety-stability control strategy to merge these two performance *** this paper,a unified approach is developed to consider safety and stability for multi-UAV formation *** stability criterion is represented by a Lyapunov function and safety criterion is represented by a barrier function and then a relaxed converse control Lyapunov-barrier theorem is *** the help of a relaxed converse control Lyapunov-barrier function(RCCLBF),a distributed safety-stability formation control strategy is proposed for the multi-UAV *** transforming the solution of RCCLBF to a Lyapunovlike stabilization problem,we show that the proposed formation control strategy can drive the UAVs staying within a specified safe *** results are provided to validate the proposed safety-stability formation control strategy.

关键词： Multi-UAV system Formation control Lyapunov function Barrier function Stability with safety guarantee

Distributed multi-agent temporal-difference learning with full neighbor information

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Control Theory and Technology 2020年第4期18卷 379-389页

作者： Zhinan Peng Jiangping Hu Rui Luo bijoy K.Ghosh School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Department of Mathematics and Statistics Texas Tech UniversityLubbockTX 79409-1042USA

This paper presents a novel distributed multi-agent temporal-difference learning framework for value function approximation,which alows agents using all the neighbor information instead of the information from only one *** full neighbor information,the proposed framework(1)has a faster convergence rate,and(2)is more robust compared to the state of-the art *** we propose a distributed multi-agent discounted temporal dfferene algorithm and a distributed muli-agent average cost temporal diference leaming algorithm based on th ***,the two proposed algorthms'theoretical convergence proofs are *** simulation resuts show that our proposed algorihms are superior to the gossip-based algorithm in convergence speed,robustness to noise and time-varying network topology.

关键词： Distributed algorithm Reinforcement learning Temprel-lifferene learning Multi-agent systems