http://hdl.handle.net/2027.42/58597 Search the Channel search http://deepblue.lib.umich.edu/simple-search http://hdl.handle.net/2027.42/58661 Title: Using Evolutionary Computation to explore geometry and topology without ground structures<br/><br/>Authors: von Buelow, Peter<br/><br/>Abstract: Over the past two decades there has been an increasing interest in using what has come to be called Evolutionary Computation (EC) in the analysis and optimization of structural systems. These methods include Genetic Algorithms (GA), Evolution Strategies (ES), Simulated Annealing and other stochastic based numerical methods. Each of these methods shares the drawback that they are very computationally intensive compared to deterministic methods. Furthermore, the computational burden can rapidly increase as the size of the analyzed structure increases. This paper suggests that the level of computation can be significantly reduced by avoiding the common practice of using ground structures in coding the topology. Additionally, comparative examples show that a broader range of good solutions can be reached when the use of ground structures is avoided.<br/><br/>Description: Extended abstract for IASS-IACM 2008 International Conference in Ithaca, NY (Cornell University) Thu, 29 May 2008 00:00:00 GMT http://hdl.handle.net/2027.42/58599 Title: A Geometric Comparison of Branching Structures in Tension and in Compression versus Minimal Paths<br/><br/>Authors: von Buelow, Peter<br/><br/>Abstract: Branching structures are based on geometric systems that expand through bifurcation without returning to form closed cells. In this sense, branching structures resemble the structure of trees that branch continually outward. In architectural engineering, these forms can be used either as tension or compression systems. Numerous built examples have been produced since the initial inspiring studies made by Frei Otto in the early 1960's. Form finding techniques based on models have been used in the past to study these forms. Although thread models can be effective in the study of force paths, they cannot distinguish between tension and compression and have no way to take member buckling into account. But buckling does have an influence on appropriate geometry of a compression system. Also, minimal paths (or pseudo minimal paths based on surface tension thread models) have been used to explore possible geometries for branching structures. In this paper, both surface tension thread models dipped in water, and weighted string models are shown in comparison with ideal tension and compression forms found with a computational method based on Genetic Algorithms. The same computational model is used to find geometries with minimal overall member length. Both 2D and 3D geometries are derived. Mon, 03 Dec 2007 00:00:00 GMT http://hdl.handle.net/2027.42/58334 Title: The View from the Top: Visualizing Downtown Ann Arbor in Three Dimensions<br/><br/>Authors: Arlinghaus, Sandra Lach; Beal, Fred J.; Kelbaugh, Douglas S.; Arlinghaus, S. L.<br/><br/>Abstract: On June 7, 2004, the Downtown Residential Taskforce presented recommendations for increasing residential land use in the downtown to the City Council of the City of Ann Arbor. Some of the policy statements in that document derived support from earlier three-dimensional analysis, using virtual reality models and derivative animations. This article displays the complete chronological unfolding of the models behind a part of this document. Broadly stated, it synthesizes theory and practice: from the academic realm of model creation and the mathematical geography behind that activity, to the real-world arena of policy and decision makers. The maps and models we make can influence the decisions that are made; conversely, the decisions we make can shape the maps and models that are built.<br/><br/>Description: Once the file is unzipped, launch ddaframeset.htm in an internet browser window. Use the buttons and links in the left frame to navigate the site. Mon, 21 Jun 2004 00:00:00 GMT http://hdl.handle.net/2027.42/57998 Title: Evaluation of the Prosecuting Attorneys’ Association of Michigan Traffic Safety Training Program<br/><br/>Authors: Kostyniuk, L.P.<br/><br/>Abstract: The purpose of the study reported here was to evaluate the Prosecuting Attorneys of Michigan Traffic Safety Training Program (TSTP). The main objective of the TSTP is to improve the ability of the state’s prosecutors to effectively prosecute violations of traffic safety laws by training new prosecutors in basic skills of prosecution applied to traffic safety law, and by assisting experienced prosecutors with prosecution of more complex traffic safety violations. The program provides training seminars, up-to-date reference materials, newsletters, advice, consultation, and technical assistance to prosecutors. It fosters communication between prosecutors and the traffic safety community through meetings, a website, and a Listserv group. A review of the TSTP for FY 2001-FY 2006 indicates that activities were thoroughly documented and consistently carried out as planned. There were a total of 1,814 attendees at the training seminars in the 6 years from 2001 to 2006, with about one-third from law enforcement. Although quantitative measures for the effectiveness were explored and pilot tested, unwillingness of prosecutors to participate in reviews of their cases, because of busy schedules, precluded a quantitative assessment of program outcomes. Instead, a survey of prosecutors (40 respondents) was carried out. Survey results indicate that prosecutors, who participated in the program are very positive about the program, report that they have applied lessons learned in the seminars to their work, and feel more confident and comfortable prosecuting impaired drivingcases. However, because self-reported measures were used, the study cannot conclusively state that the program resulted in more effective prosecution of impaired driving cases. Future evaluation efforts would benefit from further development of quantitative measures, and effectivestrategies for getting prosecutors to participate in a quantitative evaluation, which would require review of actual cases. Thu, 01 Nov 2007 00:00:00 GMT