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Manipulative operation of a target point inside a deformable object by a robotic system is necessary in many medical and industrial applications. However, this is a challenging problem because of the difficulty of imposing the motion of the target point by a finite number actuation points located at the boundary of the deformable object. In this paper, an approach towards positioning operation of...
Building emergency evacuation has long been recognized as an important issue, and crowd guidance is a key to improve egress efficiency and occupant survivability. Most existing methods assume that crowd behaviors are independent of emergency situations and are fully controllable under guidance. This assumption makes it difficult to capture important features such as stampeding or blocking. In this...
In this paper, we propose a simultaneous optimization method for task assignment and routing problems for multiple AGVs by decomposition of Petri Nets. In the proposed method, the Petri Net is decomposed into several subnets for task subproblems and AGV subproblems. Each subproblem is solved by Dijkstrapsilas algorithm. The solution of subproblem for each subnet is repeated until a feasible solution...
In this paper, we present a novel air flow modeling strategy for deep wells that is suitable for real-time control of large-scale systems. We consider the mining ventilation control application, where specifically designed models are crucial for new automation strategies based on global system control and energy consumption optimization. Two different levels of complexity are proposed. Starting from...
A production node within a network of interconnected production centers (as in supply chains) is considered in this paper, with the aim of optimizing inventory levels and production effort. The proposed Hybrid Inventory-Production model consists of two inventories (the input one for raw parts and the output one for processed parts) and a production resource which transforms parts and moves them from...
This paper presents two modeling approaches for a cooperative control problem for a homogeneous team of robots acting on a cellular two-dimensional space which includes targets and obstacles. First a combinatorial assignment and scheduling approach is used to generate collision free trajectories for the robots. The second approach formulates the optimization problem of finding collision free and optimal...
Combinatorial optimization problems arise in many applications such as task assignment, facility location, and elevator scheduling. One powerful method to address those difficult problems is the nested partitions method (NP). This method, however, cannot use historical information because it is required that the sampling of different iterations should be independent in order to guarantee global convergence...
This paper considers the task of computing (sub-) optimal continuous and discrete control trajectories for hybrid systems with a probabilistic discrete transition structure. The discrete inputs are used to block undesired transitions and to realize evolutions that are goal-attaining with high probability. An approach is proposed which combines the computation of discrete shortest-paths for given probability-levels...
This paper addresses the non-preemptive unrelated parallel machine scheduling problem with machine-dependent and job sequence-dependent setup times. All jobs are available at time zero, all times are deterministic, and the objective is to minimize the makespan. This is a NP-hard problem and in this paper, a two-stage ant colony optimization (ACO) algorithm is introduced and its performance is evaluated...
We study a single-stage, constant work-in-process (CONWIP) production system that produces one product to stock to cope with random demand. During stockout periods, the system incurs three types of potential customer loss: Balking, i.e., arriving customers may be unwilling to place orders and leave immediately. Rejection, i.e., the system rejects new customer orders if its backlog has reached a certain...
This paper attempts an as exhaustive as possible review of the control methods dedicated to optimizing the dynamic behavior of variable-speed wind energy conversion systems (WECS) from various viewpoints. Different performance criteria can be defined for WECS - e.g., the energy optimization can be achieved by operating the system at variable speed. The exploitation experience and grid-integration...
This paper reports the basic properties and robust control of a vehicle-trailer combination crosswind disturbance conditions. In practice it is known that unstable roll movements may occur, especially with unfavorable combinations of vehicle and trailer conditions, operating slightly above the permissible maximum speed. This may lead to accidents mostly due to improper driver behavior. First we present...
This work is based on research in a field of intelligent agent systems, negotiation algorithm solving tasks of energy saving, optimal electric vehicle control and transport flow control in traffic jam. Main goal of research is energy saving for public electric transport. Mathematical model and evolutionary algorithm is proposed in the paper to solve multi-criteria optimization task minimizing idle...
This paper addresses the problem of iterative optimization of the Kullback-Leibler (KL) divergence on discrete (finite) probability spaces. Traditionally, the problem is formulated in the constrained optimization framework and is tackled by gradient like methods. Here, it is shown that performing the KL optimization in a Riemannian space equipped with the Fisher metric provides three major advantages...
In the paper a hierarchical optimization method for complex systems, including control systems , characterized with replacement of the nonlinear global criterion function F(x,y) with a simpler and faster for calculation one - Psi (x,y) (unidirectional with F(x,y) ) for a subset of variable parameters in the second hierarchical level is suggested. A definition of unidirectional functions is proposed...
In this paper an identification method to estimate the parameters of a first order plus time delay model is proposed. Such a method directly obtains these parameters using a filtered equation and an optimization procedure without iterative calculations. A simple true/false criterion to establish if the hypothesis on the process type is correct can be easily derived. The proposed method shows an acceptable...
This paper deals with the problem of designing an efficient metaheuristics optimization method to tune the parameters of a Home Automation System (HAS). Using a simulation environment, the performances of a home automation system in exploiting limited resources (electricity, gas, hot water) can be described in terms of suitable indices that depend on behavioural parameters of the individual appliances...
A cascaded nonlinear sliding mode controller is proposed for power production optimization of a variable speed wind turbine equipped with a Doubly Fed Induction Generator (DFIG). The inner loop controller ensures a robust tracking of both generator torque and rotor flux, while the outer loop controller achieves a robust tracking of the optimal blade rotor speed to optimize wind energy capture. The...
This paper addresses the fault detection issue of large scale wind turbine systems. The underlying problem is very critical to enhance the reliability and reduce the cost of maintenance of wind turbines. In this work, mixed Hinfin/H- index observer is utilized to generate the residual for fault detection purpose. The employed observer is optimal in the sense that it is the least sensitive to the unknown...
Process optimization requires an accurate on-line estimation of performance indicators such as the net revenue. Measurements coupled to mass (or energy) conservation submodels are frequently used in metallurgical plants for the reconciliation of models and raw data, followed by an estimation of the plant performance. The success of real-time plant optimisation is strongly dependent on the quality...
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