Conference Agenda

Many of the 3D city models offered by the German federal states were created using a model-driven approach based on airborne laser scanning point clouds. The method consists of dividing the building footprint into small regions, for each of which a parameterized standard roof shape is chosen from a catalog in such a way that it best matches the point cloud of the corresponding roof area. A model-based approach usually means that small structures such as dormers are lost. However, these structures affect the gradient and position of the model roof segments. To obtain more accurate main roof facets that can be used as the basis for adding higher level of detail objects, a correction is required. The true plane equation of each roof facet of the given model is estimated from the point cloud using the Random Sampling Consensus (RANSAC) algorithm. If a model facet needs to be adjusted, its boundary polygon has to be recalculated. This is done with a mixed integer linear program, which changes the positions of the vertices so that they lie on as many roof planes as possible. Vertices on the cadastral footprint are allowed to be moved only on the footprint, other vertices have to stay within the (not necessarily convex) footprint polygon. In this paper, such a program is presented and applied to city models of North Rhine-Westphalia.

The global trend towards individualization, coupled with the rise of small batch sizes and increased product diversity within modular systems, is fostering a shift in manufacturing paradigms from mass production to flexible and scalable manufacturing. In this context, we present a case study focusing on the bending process, which exemplifies the need to design and optimize the underlying load-bearing structure to meet technical requirements effectively. Specifically, we address the challenge of designing a truss system capable of efficiently bearing the loads inherent in the bending process. A key aspect of our approach is the meticulous calculation of compliances, given their pivotal role in ensuring the structural integrity of the bending process. To achieve this, we leverage established Operations Research (OR) methodologies in conjunction with engineering principles.Our methodology aims to establish a robust framework for optimizing truss structures, with a unique emphasis on the utilization of additive manufacturing. This distinctive approach addresses the specialized nature of manufacturing trusses through additive processes, ensuring the efficacy of the optimization framework within this innovative manufacturing context.

Facing increased operational costs and strong competition, a leading company in the flexible workspace industry struggles with a square meter efficiency of just 33% in Oslo, rendering just 19,800 out of 60,000 sqm saleable and resulting in lost clients and under-utilized spaces. This study addresses the challenge of enhancing square meter efficiency without extensive space reconfiguration, specifically through optimizing the use of auxiliary spaces such as business lounges and meeting rooms. By utilizing historical sales data and demand patterns across some of the company’s locations in Oslo, the paper first forecasts demand and investigates stochastic variations to assess usage trends. It then identifies under-utilized auxiliary spaces that can be converted into revenue-generating workstations. Subsequently, an optimization model, structured as a multi-product newsvendor model, is developed to determine the optimal product mix. This model aims to minimize the total expected cost of shortage and under-utilization by adjusting inventory levels for each workspace type, subject to spatial configuration constraints. Anticipated challenges include managing the complications of multiple locations, varying spatial constraints in multi-floor buildings, and accommodating ongoing tenancies and fixed communal areas. The proposed approach offers insights for improving revenue potential and client retention by increasing the operational efficiency of workspace allocation.

Keywords: Workspace Optimization, Newsvendor Problem, Flexible Workspaces, Product Mix Optimization, Workspace Demand Forecasting.