Background: Personal transportation in urban areas is characterised by different transportation technologies with significantly varying properties regarding usability, infrastructural requirements and environmental impacts. This characterisation motivates the objective evaluation of mobility solutions, based on different criteria. State of the art evaluations in the scientific literature mainly focus on one specific criterion at a time. The most common criteria investigated are found in energy demand or equivalent fuel consumption. Other parameters include the traffic space demand or mean velocity as a reference for the user-related criterion "travel time". Since different modes of transport show various potentials in different criteria, an interesting point for scientific research is consideration of the different criteria in a more comprehensive evaluation approach. To address this issue, the aim of this study is to present a new approach for an objective evaluation and comparison of different transport technologies under consideration of pre-defined range of criteria and defined boundary conditions and requirements for personal mobility in cities. Besides technical-oriented aspects like driving range, transport capability and life cycle-related consumption of resources, additional factors influencing user-behaviour and traffic density are reflected. The evaluation method is presented, based on a generated exemplary data collection regarding technical and in-use characteristics of different modes of transport, mainly investigated in the city of Graz, Austria.

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This paper presents a method to decompose three dimensional complex parts into readily available stock material to take advantage of advanced joining to build up a rigid assembly. The method generates many alternative assemblies by decomposing the solid geometry iteratively with cutting planes. Each assembly is then evaluated based on cost. The process continues until the developed search algorithm converges on a near optimal solution. Application of this method will reduce material waste, thus reducing per part processing time, energy consumption, and associated production costs. Example parts for a variety of metals show how the computational tool finds near optimal solutions for complex three dimensional solids.

With the restriction of the diameter and feed direction of the cutting tool in milling process, electric discharge machining (EDM) is the only effective machining technology for the uncut regions with internal sharp corner. Automatic design of the electrode is of great significance for the CAD/CAM integration of EDM technology. In current CAD/CAM system the electrode design is done manually by technologists based on experience and knowledge. The procedure is tedious and timeconsuming. In this paper, a novel approach is proposed to automatically generate the electrode CAD model taking the topological vertices of uncut region as the hint. The hint feature points are innovatively defined and classified into three types: internal-sharp points, cutting-into points and interacting points. Based on this, our approach firstly determines the faces and the type of uncut region. Secondly, the interacting region is decomposed into the isolated region by reconstructing the topological structure, patching the split face and partitioning the shared face. Thirdly, the modeling parameters are extracted from the isolated region. Finally, the electrode CAD model is created by executing a set of generic modeling operations. The electrode CAD model can be directly used in the process planning, so as to promote the integration of CAD and CAM.

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