Relevant bibliographies by topics / Finite automata minimization

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Finite automata minimization'

Author: Grafiati
Published: 7 September 2021
Last updated: 2 February 2022

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Journal articles on the topic "Finite automata minimization"

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JEŻ, ARTUR, and ANDREAS MALETTI. "HYPER-MINIMIZATION FOR DETERMINISTIC TREE AUTOMATA." International Journal of Foundations of Computer Science 24, no. 06 (2013): 815–30. http://dx.doi.org/10.1142/s0129054113400200.

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Hyper-minimization is a recent automaton compression technique that can reduce the size of an automaton beyond the limits imposed by classical minimization. The additional compression power is enabled by allowing a finite difference in the represented language. The necessary theory for hyper-minimization is developed for (bottom-up) deterministic tree automata. The hyper-minimization problem for deterministic tree automata is reduced to the hyper-minimization problem for deterministic finite-state string automata, for which fast algorithms exist. The fastest algorithm obtained in this way runs in time [Formula: see text], where m is the size of the transition table and n is the number of states of the input tree automaton.
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Malik, D. S., John N. Mordeson, and M. K. Sen. "Minimization of fuzzy finite automata." Information Sciences 113, no. 3-4 (1999): 323–30. http://dx.doi.org/10.1016/s0020-0255(98)10073-7.

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MALETTI, ANDREAS, and DANIEL QUERNHEIM. "OPTIMAL HYPER-MINIMIZATION." International Journal of Foundations of Computer Science 22, no. 08 (2011): 1877–91. http://dx.doi.org/10.1142/s0129054111009094.

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Minimal deterministic finite automata (DFAs) can be reduced further at the expense of a finite number of errors. Recently, such minimization algorithms have been improved to run in time O(n log n), where n is the number of states of the input DFA, by [GAWRYCHOWSKI and JEŻ: Hyper-minimisation made efficient. Proc. MFCS, LNCS 5734, 2009] and [HOLZER and MALETTI: An n log n algorithm for hyper-minimizing a (minimized) deterministic automaton. Theor. Comput. Sci. 411, 2010]. Both algorithms return a DFA that is as small as possible, while only committing a finite number of errors. These algorithms are further improved to return a DFA that commits the least number of errors at the expense of an increased (quadratic) run-time. This solves an open problem of [BADR, GEFFERT, and SHIPMAN: Hyper-minimizing minimized deterministic finite state automata. RAIRO Theor. Inf. Appl. 43, 2009]. In addition, an experimental study on random automata is performed and the effects of the existing algorithms and the new algorithm are reported.
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RAMASUBRAMANIAN, S. V., and KAMALA KRITHIVASAN. "FINITE AUTOMATA AND DIGITAL IMAGES." International Journal of Pattern Recognition and Artificial Intelligence 14, no. 04 (2000): 501–24. http://dx.doi.org/10.1142/s0218001400000325.

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In this paper, we initially consider representation of 2D black–white images and 3D objects using finite state automata. We describe transformation of scaling on the 2D image by an operation on the FSA. We also give constructions for getting the projections of a 3D object on to coordinate planes and for reconstructing the 3D object from its projections. We define minimization of nondeterministic FSAs and give an O(e2) (e is the number of edges in the FSA) algorithm for minimization of NFAs. Later, we define a WFA and describe various properties of WFA. We define four normal forms of WFA and show how a WFA can be normalized into any of these forms. We show the equivalence of WFAs with ∊ edges and ∊-free WFAs. Then, we define minimization of WFAs and present an algorithm to minimize a WFA.
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Wang, Yongbing, and Yongming Li. "Minimization of lattice multiset finite automata." Journal of Intelligent & Fuzzy Systems 35, no. 1 (2018): 627–37. http://dx.doi.org/10.3233/jifs-161382.

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Cheng, Wei, and Zhi-Wen Mo. "Minimization algorithm of fuzzy finite automata." Fuzzy Sets and Systems 141, no. 3 (2004): 439–48. http://dx.doi.org/10.1016/s0165-0114(02)00607-3.

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Ouardi, Faissal, Zineb Lotfi, and Bilal Elghadyry. "Efficient Construction of the Equation Automaton." Algorithms 14, no. 8 (2021): 238. http://dx.doi.org/10.3390/a14080238.

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This paper describes a fast algorithm for constructing directly the equation automaton from the well-known Thompson automaton associated with a regular expression. Allauzen and Mohri have presented a unified construction of small automata and gave a construction of the equation automaton with time and space complexity in O(mlogm+m2), where m denotes the number of Thompson automaton transitions. It is based on two classical automata operations, namely epsilon-removal and Hopcroft’s algorithm for deterministic Finite Automata (DFA) minimization. Using the notion of c-continuation, Ziadi et al. presented a fast computation of the equation automaton in O(m2) time complexity. In this paper, we design an output-sensitive algorithm combining advantages of the previous algorithms and show that its computational complexity can be reduced to O(m×|Q≡e|), where |Q≡e| denotes the number of states of the equation automaton, by an epsilon-removal and Bubenzer minimization algorithm of an Acyclic Deterministic Finite Automata (ADFA).
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Gong, Wei, and Jian Shi. "Equivalence of Transducer." Applied Mechanics and Materials 397-400 (September 2013): 761–64. http://dx.doi.org/10.4028/www.scientific.net/amm.397-400.761.

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Today Finite Automata are used in several areas of economy and research, for example in language and text processing or E-Commerce. There are often automata with more than hundred thousand states. Minimization of such automata can only be done by classical minimization methods. But this doesnt produce Minimal Finite Automata with output. A Transducer is a special Finite Automata that produces an output. One of the challenges is to test the equivalence of Transducers, this will be shown in this paper.
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Melnikov, B. F., and A. A. Melnikova. "Edge-minimization of non-deterministic finite automata." Korean Journal of Computational & Applied Mathematics 8, no. 3 (2001): 469–79. http://dx.doi.org/10.1007/bf02941980.

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Peeva, Ketty G. "Behaviour, reduction and minimization of finite -automata." Fuzzy Sets and Systems 28, no. 2 (1988): 171–81. http://dx.doi.org/10.1016/0165-0114(88)90198-4.

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Dissertations / Theses on the topic "Finite automata minimization"

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Watson, Bruce William. "Constructing minimal acyclic deterministic finite automata." Thesis, University of Pretoria, 2010. http://hdl.handle.net/2263/23648.

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This thesis is submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Ph.D) in the FASTAR group of the Department of Computer Science, University of Pretoria, South Africa. I present a number of algorithms for constructing minimal acyclic deterministic finite automata (MADFAs), most of which I originally derived/designed or co-discovered. Being acyclic, such automata represent finite languages and have proven useful in applications such as spellchecking, virus-searching and text indexing. In many of those applications, the automata grow to billions of states, making them difficult to store without using various compression techniques — the most important of which is minimization. Results from the late 1950’s show that minimization yields a unique automaton (for a given language), and later results show that minimization of acyclic automata is possible in time linear in the number of states. These two results make for a rich area of algorithmics research; automata and algorithmics research are relatively old fields of computing science and the discovery/invention of new algorithms in the field is an exciting result. I present both incremental and nonincremental algorithms. With nonincremental techniques, the unminimized acyclic deterministic finite automaton (ADFA) is first constructed and then minimized. As mentioned above, the unminimized ADFA can be very large indeed — often even too large to fit within the virtual memory space of the computer. As a result, incremental techniques for minimization (i.e. the ADFA is minimized during its construction) become interesting. Incremental algorithms frequently have some overhead: if the unminimized ADFA fits easily within physical memory, it may still be faster to use nonincremental techniques. The presentation used in this thesis has a few unusual characteristics: <ul><li> Few other presentations follow a correctness-by-construction style for presenting and deriving algorithms. The presentations given here include correctness arguments or sketches thereof. </li><li> The presentation is taxonomic — emphasizing the similarities and differences between the algorithms at a fundamental level. </li><li> While it is possible to present these algorithms in a formal-language-theoretic setting, this thesis remains somewhat closer to the actual implementation issues. </li><li> In several chapters, new algorithms and interesting new variants of existing algorithms are presented. </li><li> It gives new presentations of many existing algorithms — all in a common format with common examples. </li><li> There are extensive links to the existing literature. </li></ul><br>Thesis (PhD)--University of Pretoria, 2011.<br>Computer Science<br>unrestricted
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Kaati, Lisa. "Reduction Techniques for Finite (Tree) Automata." Doctoral thesis, Uppsala universitet, Avdelningen för datorteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9330.

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Finite automata appear in almost every branch of computer science, for example in model checking, in natural language processing and in database theory. In many applications where finite automata occur, it is highly desirable to deal with automata that are as small as possible, in order to save memory as well as excecution time. Deterministic finite automata (DFAs) can be minimized efficiently, i.e., a DFA can be converted to an equivalent DFA that has a minimal number of states. This is not the case for non-deterministic finite automata (NFAs). To minimize an NFA we need to compute the corresponding DFA using subset construction and minimize the resulting automaton. However, subset construction may lead to an exponential blow-up in the size of the automaton and therefore even if the minimal DFA may be small, it might not be feasible to compute it in practice since we need to perform the expensive subset construction. To aviod subset construction we can reduce the size of an NFA using heuristic methods. This can be done by identifying and collapsing states that are equal with respect to some suitable equivalence relation that preserves the language of the automaton. The choice of an equivalence relation is a trade-off between the desired amount of reduction and the computation time since the coarser a relation is, the more expensive it is to compute. This way we obtain a reduction method for NFAs that is useful in practice. In this thesis we address the problem of reducing the size of non-deterministic automata. We consider two different computation models: finite tree automata and finite automata. Finite automata can be seen as a special case of finite tree automata and all of the previously mentioned results concerning finite automata are applicable to tree automata as well. For non-deterministic bottom-up tree automata, we present a broad spectrum of different relations that can be used to reduce their size. The relations differ in their computational complexity and reduction capabilities. We also provide efficient algorithms to compute the relations where we translate the problem of computing a given relation on a tree automaton to the problem of computing the relation on a finite automaton. For finite automata, we have extended and re-formulated two algorithms for computing bisimulation and simulation on transition systems to operate on finite automata with alphabets. In particular, we consider a model of automata where the labels are encoded symbolically and we provide an algorithm for computing bisimulation on this partial symbolic encoding.
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FRANCH, Daniel Kudlowiez. "Dynamical system modeling with probabilistic finite state automata." Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/25448.

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Submitted by Fernanda Rodrigues de Lima (fernanda.rlima@ufpe.br) on 2018-08-02T22:51:47Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Daniel Kudlowiez Franch.pdf: 1140156 bytes, checksum: c02b1b4ca33f8165be5960ba5a212730 (MD5)<br>Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-08-07T21:11:31Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Daniel Kudlowiez Franch.pdf: 1140156 bytes, checksum: c02b1b4ca33f8165be5960ba5a212730 (MD5)<br>Made available in DSpace on 2018-08-07T21:11:31Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Daniel Kudlowiez Franch.pdf: 1140156 bytes, checksum: c02b1b4ca33f8165be5960ba5a212730 (MD5) Previous issue date: 2017-03-10<br>FACEPE<br>Discrete dynamical systems are widely used in a variety of scientific and engineering applications, such as electrical circuits, machine learning, meteorology and neurobiology. Modeling these systems involves performing statistical analysis of the system output to estimate the parameters of a model so it can behave similarly to the original system. These models can be used for simulation, performance analysis, fault detection, among other applications. The current work presents two new algorithms to model discrete dynamical systems from two categories (synchronizable and non-synchronizable) using Probabilistic Finite State Automata (PFSA) by analyzing discrete symbolic sequences generated by the original system and applying statistical methods and inference, machine learning algorithms and graph minimization techniques to obtain compact, precise and efficient PFSA models. Their performance and time complexity are compared with other algorithms present in literature that aim to achieve the same goal by applying the algorithms to a series of common examples.<br>Sistemas dinâmicos discretos são amplamente usados em uma variedade de aplicações cientifícas e de engenharia, por exemplo, circuitos elétricos, aprendizado de máquina, meteorologia e neurobiologia. O modelamento destes sistemas envolve realizar uma análise estatística de sequências de saída do sistema para estimar parâmetros de um modelo para que este se comporte de maneira similar ao sistema original. Esses modelos podem ser usados para simulação, referência ou detecção de falhas. Este trabalho apresenta dois novos algoritmos para modelar sistemas dinâmicos discretos de duas categorias (sincronizáveis e não-sincronizáveis) por meio de Autômatos Finitos Probabilísticos (PFSA, Probabilistic Finite State Automata) analisando sequências geradas pelo sistema original e aplicando métodos estatísticos, algoritmos de aprendizado de máquina e técnicas de minimização de grafos para obter modelos PFSA compactos e eficientes. Sua performance e complexidade temporal são comparadas com algoritmos presentes na literatura que buscam atingir o mesmo objetivo aplicando os algoritmos a uma série de exemplos.
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Bartůněk, Petr. "Knihovna operací nad konečnými automaty." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2010. http://www.nusl.cz/ntk/nusl-237128.

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This work deals with two basic operations over finite automata. Determination of nondeterministic finite automata and minimization of deterministic finite automata. For these two operations I proposed sequential algorithms that are parallelizable. I deal mainly with finding the speedup of SSE instructions, or use the OpenMP library. The trend today is mainly in increasing the number of processors, so I propose parallel algorithms for multiple processors. When searching for the optimal solution, I will be to examine other ways to achieve speedup, for example efficient saving of the data structures in memory.
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Figueiredo, Daniel Oliveira. "Differential dynamic logic and applications." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/16841.

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Mestrado em Matemática e Aplicações<br>Na área industrial e habitual usar ferramentas discretas em sistemas cuja evolução e contínua e regida pelas leis da mecânica. Estes sistemas que apresentam tanto comportamento contínuo como discreto são conhecidos como sistemas híbridos. A lógica diferencial dinâmica e uma lógica desenvolvida recentemente para trabalhar com estes sistemas. Neste trabalho, apresentamos a lógica diferencial dinâmica como uma generalização da lógica dinâmica (e, consequentemente, da lógica modal). Também são apresentadas algumas aplicações e discutida a utilidade destas lógicas nas áreas da mecânica e da biologia. Embora o uso de ferramentas computacionais seja comum e os resultados até agora obtidos sejam satisfatórios, os exemplos apresentados mostram que a lógica diferencial dinâmica pode ser usada como uma alternativa, assim como um complemento, na biologia sintética<br>In industry, it is often used discrete tools in system which behavior is continuous and modeled by the laws of mechanics. These systems which display both continuous and discrete dynamic behavior are known as hybrid systems. Di erential dynamic logic is a logic recently developed in order to reasoning about hybrid systems. In this work, we present the di erential dynamic logic as a generalization of dynamic logic (and consequently of modal logic). We also present some applications and we discuss about the utility of using these logics in the areas of mechanics and molecular biology. Although computational tools have been applied to reasoning about biological regulatory networks with satisfactory results, our examples show that di erential dynamic logic can be used as an alternative, or even as a complement, in synthetic biology.
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Kshatriya, Jagannath Rajini Singh. "Visualizing the minimization of a deterministic finite state automaton." Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/kshatriyajagannath/KshatriyaJagannathR1207.pdf.

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Maťas, Marek. "Metody analýzy stavových automatů pro vestavné aplikace." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218940.

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This master’s thesis deals with analysis of state machines for embedded applications. The issue of finite-state machine is described theoretically. The document also contains a proposal for funding for modeling finite state machines in Matlab/Simulink. It is designed data representation of finite automaton. Over this data representation algorithm of minimization is applied. Finally, the algorithm is implemented to generate code in C language.
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Procházka, Lukáš. "Redukce nedeterministických konečných automatů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2011. http://www.nusl.cz/ntk/nusl-237032.

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Nondeterministic finite automaton is an important tool, which is used to process strings in many different areas of programming. It is important to try to reduce its size for increasing programs' effectiveness. However, this problem is computationally hard, so we need to search for new techniques. Basics of finite automata are described in this work. Some methods for their reduction are then introduced. Usable reduction algorithms are described in greater detail. Then they are implemented and tested. The test results are finally evaluated.
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Muller, Graham. "Minimization of symmetric difference finite automata." Thesis, 2006. http://hdl.handle.net/10019.1/1922.

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Thesis (MSc (Computer Science))--University of Stellenbosch, 2006.<br>The minimization of a Finite Automaton (FA) deals with the construction of an equivalent FA with the least number of states. Traditional FAs and the minimization thereof is a well defined and researched topic within academic literature. Recently a generalized form of the FA, namely the generalized FA(*-FA), has been derived from these traditional FAs. This thesis investigates the minimization and reduction of one case of ...
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Book chapters on the topic "Finite automata minimization"

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Björklund, Johanna, and Loek Cleophas. "Minimization of Finite State Automata Through Partition Aggregation." In Language and Automata Theory and Applications. Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-53733-7_16.

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Melnikov, Boris, and Aleksandra Melnikova. "Basis Finite Automata in Some Minimization Problems. Part I: Introduction and the General Description of the Algorithms." In Software Engineering Perspectives in Intelligent Systems. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-63322-6_54.

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Pivneva, Svetlana V., Tatyana N. Ivanova, Galina V. Akhmetzhanova, Anastasia A. Kurilova, and Julia A. Anisimova. "Applying an Algorithm for Vertex Minimization of Non-deterministic Finite Automata (NFA) on the Basis of a Multi-heuristic Approach for Studying Social and Economic Performances of Region." In The Future of the Global Financial System: Downfall or Harmony. Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-00102-5_87.

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Zhang, Kun, and Zhi-wen Mo. "Minimization of Lattice-Valued Moore Type of Finite Automaton." In Advances in Intelligent and Soft Computing. Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-28592-9_25.

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"Finite Automata Minimization." In Handbook of Finite State Based Models and Applications. Chapman and Hall/CRC, 2016. http://dx.doi.org/10.1201/b13055-12.

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Conference papers on the topic "Finite automata minimization"

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Martinek, Pavel. "Some notes to minimization of multiset finite automata." In INTERNATIONAL CONFERENCE OF NUMERICAL ANALYSIS AND APPLIED MATHEMATICS (ICNAAM 2017). Author(s), 2018. http://dx.doi.org/10.1063/1.5044089.

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Lamperti, Gianfranco, and Michele Scandale. "Incremental Determinization and Minimization of Finite Acyclic Automata." In 2013 IEEE International Conference on Systems, Man and Cybernetics (SMC 2013). IEEE, 2013. http://dx.doi.org/10.1109/smc.2013.385.

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Eisner, Jason. "Simpler and more general minimization for weighted finite-state automata." In the 2003 Conference of the North American Chapter of the Association for Computational Linguistics. Association for Computational Linguistics, 2003. http://dx.doi.org/10.3115/1073445.1073454.

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Aravind, Sudip, and Rony Mathews. "A Cognitive Approach for Optimal Minimization of State Transitions in Nondeterministic Finite Automata." In 2012 Fourth International Conference on Computational Intelligence, Modelling and Simulation (CIMSiM). IEEE, 2012. http://dx.doi.org/10.1109/cimsim.2012.35.

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Melnikov, Boris, and Andrey Tsyganov. "The State Minimization Problem for Nondeterministic Finite Automata: The Parallel Implementation of the Truncated Branch and Bound Method." In 2012 Fifth International Symposium on Parallel Architectures, Algorithms and Programming (PAAP). IEEE, 2012. http://dx.doi.org/10.1109/paap.2012.36.

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Martin, Thomas J., George S. Dulikravich, Zhen-Xue Han, and Brian H. Dennis. "Minimization of Coolant Mass Flow Rate in Internally Cooled Gas Turbine Blades." In ASME 1999 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/99-gt-146.

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This paper presents a coupled aerodynamic and thermal study of computer-automated design and optimization of internally cooled turbine blades. The turbine blade, thermal barrier coating, coolant passages and struts were developed from a set of design variables, including β-splines for the coolant wall thickness distribution. The turbine inlet temperature, mass flow rate, and coolant wall roughness were also incorporated into the design variable set. The maximum temperature in the metal blade was enforced with equality or inequality constraint functions. Because the coolant flow rate was a design variable, this function could not be explicitly minimized. Instead, three different thermal objective functions were studied: uniform temperature, heat flux extremum, and minimum coolant ejection temperature. Results have shown that it is possible to increase or maintain high turbine inlet temperatures while decreasing the turbine blade coolant requirements. A new constrained hybrid optimization algorithm was developed and used to modify the turbine blade designs until an optimum design was found. This evolutionary optimization package incorporated four popular algorithms (steepest descent, genetic, simplex, and simulated annealing) with automatic switching among them. A computational heat conduction analysis, using the boundary element method (BEM), was iteratively coupled to an unstructured finite volume Reynolds-averaged Navier-Stokes CFD analysis for turbulent hot gas flow. A quasi-one-dimensional system with heat addition and friction was iteratively coupled to the BEM heat conduction via heat flux for the simulation of the airflow in the serpentine coolant passages. This quasi-one-dimensional system yielded correlations for the heat convection coefficients on the coolant passage walls. The coolant passage pressure loss was one of the quantities arising from the quasi-one-dimensional analysis.
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Pugazhendhi, K., and A. K. Dhingra. "Reliability Based Design Optimization Using Automatic Differentiation." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-65912.

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Typically, a reliability based design optimization (RBDO) problem is solved as a nested optimization problem because an evaluation of the probabilistic constraint(s) involves solving a minimization problem. Over the years, a number of algorithms have been developed to solve the RBDO problem efficiently. All of these approaches involve an evaluation of derivatives of the responses. In this paper, a decoupled approach using automatic differentiation (AD) is presented to solve the RBDO problem. The proposed approach employs AD to evaluate the reliability, as well as to evaluate the sensitivity of the most probable point (MPP) with respect to the design variables. Since these evaluations involve a computation of the Jacobian and the Hessian, a use of AD improves the accuracy while simultaneously reducing the required number of response evaluations. The applicability of the proposed approach is shown through examples of increasing complexity ranging from problems where closed form solutions are available for evaluation of response to situations where finite element analysis is needed to compute the system response.
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Bankert, Raymond J., Vinod K. Singh, and Harindra Rajiyah. "Model Based Diagnostics and Prognosis System for Rotating Machinery." In ASME 1995 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/95-gt-252.

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A PC-based automated mechanical vibration diagnostic and prognosis system for rotating machinery is under development by integrating AI-expert system-based interpretative capabilities with rotor dynamics based modeling and numerical optimization techniques. Presented here are the details involved while generating a rotor dynamic simulator: A turbine-generator is properly modeled using the finite element approach to compute steady-state response. The bearing stiffness and damping properties are computed by numerically solving the Reynold’s equation. An optimizer software has been interfaced with the rotor dynamics code for the solution of nonlinear unconstrained function minimization. A finite element based closed form approach has been adopted to compute the gradients of the objective function. The model is perturbed by the optimizer to match the results with simulated field measurement. The model based optimization technique has been demonstrated on a 120 mass, 6 bearing rotor system. After optimization, the responses and mass unbalance converge to their goal (field) values. To date, feasibility studies show encouraging results to differentiate between mass unbalance and misalignment for realistic systems using this methodology.
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Camburn, Bradley, Kristin Wood, Richard Crawford, and Dan Jensen. "Novel Geometrical Approach to Designing Flow Channels." In ASME 2012 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/detc2012-71448.

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Many natural systems that transport heat, energy or fluid from a distributed volume to a single flow channel exhibit an analogous appearance to trees (examples include bronchial tubes, watersheds, lightening, and blood vessels). Several authors have proceeded with analytical methods to develop fractal or pseudo-fractal designs analogous to these natural instances. This implicates an implicit belief in some designers that there is an optimal attribute to this ‘tree-like’ appearance. A novel explanation for the appearance of these systems is presented in this paper. Natural systems follow the path of least resistance; or in other words, minimize transport effort. Effort is required to overcome all forms of friction (an unavoidable consequence of motion). Therefore effort minimization is analogous to transport distance (path length) minimization. Effort due to friction will be integrated over the total transport distance. Leveraging this observation a simple, geometric explanation for the emergent ‘tree-like’ architecture of many natural systems is now achievable. Note that this ‘tree’ effect occurs when most of the flow volume exhibits diffusion, with a small percentage of interdigitated high flow velocity channels. One notable application of our novel method, path length analysis, is the automated creation of cooling channel networks for heat generating micro-chips. As a demonstration, this path length analysis method was used to develop a significantly more efficient channel configuration (by 14%) than the state of the art for conductive microchip cooling. An extensive array of finite element models confirms the performance of this novel configuration.
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10

Sriram, Anirudh Roshan, DeLean Tolbert, Monica Cardella, and Karthik Ramani. "Bridging the Gaps: Augmenting Design Learning Through Computer-Aided Exploration." In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/detc2015-46978.

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Abstract:
In helping students learn engineering design, it is very important that they explore complex scenarios that are realistic, and fall outside the domain of standard and over-simplified textbook problems that typically have an answer. A majority of the current educational methods and computer-based tools do not bridge this gap and lack affordances for design exploration. Although computational methods such as Finite Element Analysis have this potential, they are hard to use requiring the users to spend a significant effort. Also, several instructors have identified significant knowledge gaps in concepts related to structural design and strength of materials when the students reach their senior year. To this end, we have developed a problem-based framework to allow for rapid design exploration within engineering design curricula using an easy-to-use, simplified and constrained version of finite elements for stress analysis and exploration. Our framework makes it possible for users to rapidly explore various design options by incorporating a Finite Element Analysis (FEA) backend for design exploration. Our approach uses a constrained design problem for weight minimization that incorporates elements of structural topology optimization but does not automate it. Instead we provide the user the control on decision making for changing the shape through material removal. Using this framework, we explore the decision making of users, and their methodology in the course of the activities that provide a context of control, challenge and reflection. Using video and verbal protocol analysis we integrate assessment in ways that are important and interesting for learning. Our framework demonstrates that the ability of computational tools that are transformed for learning purposes can scaffold and augment learning processes in new ways.
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