Objective. The default window setting on PET/CT workstations is soft tissue. This study investigates whether bone windowing and hybrid FDG PET/CT can help differentiate between malignant and benign primary bone tumors. Materials and methods. A database review included 98 patients with malignant (n=64) or benign primary bone (n=34) tumors. The reference standard was biopsy for malignancies and b...

We address the Home Health Care Delivery Problem (HHCDP), which is concerned with staff scheduling in the home health care industry. The goal is to schedule health care providers to serve patients at their homes that maximizes the total collected preference scores from visited patients subject to several constraints, such as workload of the health care providers, time budget for each provider a...

Most time-dependent vehicle routing problems are based on a similar modeling paradigm: travel time information is represented by functions between pairs of points interest (e.g., depot or customers). Only few papers investigate how these can be computed using the available information. Furthermore, most them neglect possibility that different paths could selected in road network depending compr...

The topic of this paper is a Genetic Algorithm solution to the Vehicle Routing Problem with Time Windows, a variant of one of the most common problems in contemporary operations research. The paper will introduce the problem starting with more general Traveling Salesman and Vehicle Routing problems and present some of the prevailing strategies for solving them, focusing on Genetic Algorithms. A...

In this paper we describe a method for optimistic parallel discrete event simulation for multi-agent systems. We present an adaptive metric that calculates the appropriate degree of optimism for an agent process based on the reads and writes made to the shared state by that agent. We conclude by showing how results from our investigations into the application of moving time windows in agent sim...

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In order to study how n to 1 convergence sharpens timing information, we have used a simple time-window (TW) model in which the target neuron fires the first time it has received m action potentials in the previous εmilleseconds. Although the TW is convenient for proving theorems and Monte-Carlo simulations, it is a natural question whether it represents well the physiological reality. We first...

We consider a multicommodity routing problem, where demands are released online and have to be routed in a network during specified time windows. The objective is to minimize a time and load dependent convex cost function of the aggregate arc flow. First, we study the fractional routing variant. We present two online algorithms, called Seq and Seq. Our first main result states that, for cost fu...

Crossdocking studies have mostly been concerned with the physical layout of a crossdock or on a single crossdock. In this work, we study a network of crossdocks taking into consideration delivery and pickup time windows, warehouse capacities and inventory handling costs. Because of the complexity of the problem, local search techniques are developed and used with simulated annealing and tabu se...