Logistics Planning Using the POEM Language System

In modern logistics, multi-modal transport planning and vehicle routing represent two major problems. Within a supply chain, the first determines how to forward freight between different regions, while the second plans the local fleet of vehicles, both in order to minimize transport costs. These problems are significant for thirdand/or fourth-party logistics. In practice, complex transport conditions such as on-time delivery, capacity (quantity/volume/weight), work regulation (time/break/makespan), transport mode, security and coupling constraints may lead to computational challenges for the optimization engine. 1. POEM SOLUTION BUILDER POEM (Programming in Operational and Expressive Models) is a planning and scheduling solution-building system. The POEM Solution Builder is composed of a core technology and an auxiliary one: Natural Constraint Language (NCL) and Visual Script. NCL is a descriptive language for business modelling and problem-solving based on conventional mathematical logic. Visual Script in POEM is a GUI script that supports solution visualization (basic graphics/map/time) and interaction management. In an all-in-one style, POEM embeds operations research algorithms, logic, heuristic rules and GUI in a single system to offer users a cost-efficient choice with benefits in training, management, development, deployment and maintenance. As a development tool, POEM narrows the gap between developers and end users thanks to its visual modelling and debugging interface. Figure 1 shows the visual nature of POEM modelling and diagnosing. Figure 1 POEM Solution Builder modelling and diagnosing in a visual manner. POEM is also designed to be an application platform. In order that a single solver can support a variety of applications, POEM advocates the development of modular solutions for different businesses. For instance, production planning and scheduling, distribution optimization and personnel planning can all be performed on the POEM platform. To illustrate this point, two POEM solutions for logistics planning are presented below.