Fast and exact audit scheduling optimization

A faster exact method for solving the robust multi-mode resource-constrained project scheduling problem

This paper presents a mixed-integer linear programming formulation for the multi-mode resource-constrained project scheduling problem with uncertain activity durations. We consider a two-stage robust optimisation approach and find solutions that minimise the worst-case project makespan, whilst assuming that activity durations lie in a budgeted uncertainty set. Computational experiments show that this easy-to-implement formulation is many times faster than the current state-of-the-art solution approach for this problem, whilst solving over 40% more instances to optimality over the same benchmar…

Delay Estimation and Fast Iterative Scheduling Policies for LTE Uplink

We consider the allocation of spectral and power resources to the mobiles (i.e., user equipment (UE)) in a cell every subframe (1 ms) for the Long Term Evolution (LTE) orthogonal frequency division multiple access (OFDMA) cellular network. To enable scheduling based on packet delays, we design a novel mechanism for inferring the packet delays approximately from the buffer status reports (BSR) transmitted by the UEs; the BSR reports only contain queue length information. We then consider a constrained optimization problem with a concave objective function - schedulers such as those based on uti…

An Approximate Method for the Optimization of Long-Horizon Tank Blending and Scheduling Operations

We address a challenging tank blending and scheduling problem regarding operations for a chemical plant. We model the problem as a nonconvex MIQCP, then approximate this model as a MILP using a discretization-based approach. We combine a rolling horizon approach with the discretization of individual chemical property specifications to deal with long scheduling horizons, time-varying quality specifications, and multiple suppliers with discrete arrival times. This approach has been evaluated using industry-representative data sets from the specialty chemical industry. We demonstrate that the pro…

非线性系统中轮换调度控制输入的稳定性研究

Stabilization under round robin scheduling of control inputs in nonlinear systems

本文研究了在反馈控制器稀疏化情况下多变量控制仿射非线性系统的稳定性，证明了在轮换调度方案下，适当缩放的局部渐进稳定反馈控制器可使系统平衡点稳定，并在一定条件下保证局部渐进稳定，同时保持吸引盆地不变。

Fast Learning for Renewal Optimization in Online Task Scheduling

This paper considers online optimization of a renewal-reward system. A controller performs a sequence of tasks back-to-back. Each task has a random vector of parameters, called the task type vector, that affects the task processing options and also affects the resulting reward and time duration of the task. The probability distribution for the task type vector is unknown and the controller must learn to make efficient decisions so that time average reward converges to optimality. Prior work on such renewal optimization problems leaves open the question of optimal convergence time. This paper d…

Optimal dispatch schedule for a fast EV charging station with account to supplementary battery health degradation

This paper investigates the usage of battery storage systems in a fast charging station (FCS) for participation in energy markets and charging electrical vehicles (EVs) simultaneously. In particular, we focus on optimizing the scheduling strategies to reduce the overall operational cost of the system over its lifetime by combining the model of battery degradation and energy arbitrage. We implement the battery degradation as a penalty term within an energy arbitrage model and show that the battery degradation plays an important role in the optimal energy dispatch scheduling of the FCS system. I…