436 research outputs found

    Fratura de ângulo de mandíbula: avaliação do comportamento mecânico do osso variando o material para fixação (TiCP e Ti-Mo) e a técnica de fixação interna rígida (Champy e AO/ASIF), com o método dos elementos finitos tridimensional

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    The aim of this study was to analyze the mechanical behavior of bone after simulation of fracture of the mandibular angle and rigid internal fixation using plates and screws made from commercially pure titanium (TiCP) and an experimental titanium- molybdenum alloy (Ti-Mo). In addition, two rigid internal fixation techniques were analyzed: Champy technique and AO/ASIF technique. The tomographic image from a radiopaque physical replica of the mandible was used to generate a geometric model similar to the physical replica with Mimics software. The plates and screws were modeled in the graphic design program SolidWorks v.2009 and adapted to the mandible. Thus, 4 geometric models representing part of the mandibular body, ramus, and mandibular angle with the fracture fixed with plates and screws were specify the following groups: group 1 - a segment of the mandibular angle fractured, with internal fixation by Champy technique, using plates and screws of commercially pure titanium (Ti-CP), group 2 - a segment of the mandibular angle fractured, with internal fixation by Champy technique, using a plate and screws of experimental titanium-based molybdenum alloy (Ti-Mo), group 3 - a segment of the mandibular angle fractured, with internal fixation by Association Osteosynthesis/Association for the Study of Internal Fixation (AO/ASIF) technique, using plate and screws of commercially pure titanium (Ti-CP), group 4 - a segment of the mandibular angle fractured, with rigid internal fixation by AO/ASIF technique, using plate and screws of experimental titanium-molybdenum alloy (Ti-Mo). In all simulations, the cross-sectional area of the ramus was fixed in the x, y and z axes (x = y = z = 0). A distributed load of 200N was applied to the occlusal surface of a mandibular first molar. The numerical analysis was performed using the finite element software, Ansys Workbench 10.0. The results...O presente trabalho tem por objetivo analisar o comportamento mecânico do osso após a simulação de fratura do ângulo mandibular e subsequente fixação interna rígida dos segmentos utilizando placas e parafusos confeccionados a partir de titânio comercialmente puro (TiCP) e de uma liga experimental de titânio-molibdênio (Ti-Mo). Duas técnicas de fixação interna rígida foram analisadas: técnica de Champy e técnica da AO/ASIF. A imagem tomográfica de uma réplica física da mandíbula em material radiopaco foi utilizada para a geração de um modelo geométrico semelhante ao modelo físico, com o auxílio do programa Mimics. As placas e parafusos foram modelados no programa de desenho gráfico SolidWorks, v.2009, e adaptados à mandíbula. Desta forma, 4 modelos geométricos representando parte do corpo, do ramo e ângulo mandibular, com a fratura na região do ângulo fixada com placas e parafusos, especificaram os seguintes grupos: grupo 1 - segmento de mandíbula com fratura angular com fixação interna rígida, pela técnica de Champy, utilizando placa e parafusos de titânio comercialmente puro (Ti-CP), grupo 2 - segmento de mandíbula com fratura angular com fixação interna rígida, pela técnica de Champy, utilizando placa e parafusos de uma liga experimental a base de titânio-molibdênio (Ti-Mo); grupo 3 - segmento de mandíbula com fratura angular com fixação interna rígida, fixada pela técnica da Associação para estudo das Association Osteosynthesis/Association for the Study of Internal Fixation (AO/ASIF), utilizando placa e parafusos de titânio comercialmente puro (Ti-CP); grupo 4 - segmento de mandíbula com fratura angular com fixação interna rígida, fixada pela técnica da AO/ASIF, utilizando placa e parafusos de uma liga experimental a base de titânio-molibdênio..

    Embedding spanning subgraphs into large dense graphs

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    In this thesis we are going to present some results on embedding spanning subgraphs into large dense graphs. Spanning Trees Bollob'as conjectured that if GG is a graph on nn vertices, delta(G)geq(1/2+epsilon)ndelta(G) geq (1/2 + epsilon) n for some epsilon>0epsilon > 0, and TT is a bounded degree tree on nn vertices, then TT is a subgraph of GG. The problem was solved in the affirmative by Koml'os, S'ark"ozy and Szemer'edi for large graphs. They then strengthened their result, and showed that the maximum degree of TT need not be bounded: there exists a constant cc such that TT is a subgraph of GG if Delta(T)leqcn/lognDelta(T) leq cn / log n, delta(G)geq(1/2+epsilon)ndelta(G) geq (1/2 + epsilon) n and nn is large. Both proofs are based on the Regularity Lemma-Blow-up Lemma Method. Recently, using other methods, it was shown that bounded degree trees embed into graphs with minimum degree n/2+Clognn/2 + C log n, where CC is a constant depending on the maximum degree of TT. Here we show that in general n/2+O(Delta(T)cdotlogn)n/2 + O(Delta(T) cdot log n) is sufficient for every Delta(T)leqcn/lognDelta(T) leq cn / log n. We also show that this bound is tight for the two extreme values of mm i.e. when m=Cm = C and when m=cn/lognm = cn / log n. Powers of Hamiltonian Cycles In 1962 P'osa conjectured that if delta(G)geqfrac23ndelta(G) geq frac{2}{3}n then GG contains the square of a Hamiltonian cycle. Later, in 1974, Seymour generalized this conjecture: if delta(G)geq(frack1k)ndelta(G) geq (frac{k-1}{k})n then GG contains the (k1)(k-1)th power of a Hamiltonian cycle. In 1998 the conjecture was proved by Koml'os, S'ark"ozy and Szemer'edi for large graphs using the Regularity Lemma. We present a ``deregularised" proof of the P'osa-Seymour conjecture which results in a much lower threshold value for nn, the size of the graph for which the conjecture is true. We hope that the tools used in this proof will push down the threshold value for nn to around 100 at which point we will be able to verify the conjecture for every nn.Ph.D.Includes bibliographical referencesIncludes vitaby Asif Jamshe

    High-throughput near-infrared spectroscopy analysis of nutritional composition in sweet potato stem tips

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    http://dx.doi.org/10.13039/501100011798 Ministry of Agriculture and Rural Affairs of the People's Republic of Chin

    Prediction of particle concentration profiles in binary-solid liquid fluidized bed

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    A simple mixing rule is presented here to predict the concentration profile of individual particle species in a binary-solid liquid fluidized bed from the information about the total solid concentration in the bed. Using the experimental data available in the literature, the applicability of this approach is demonstrated for the presence of different size particles in the bed. For the case of binary-solid fluidized bed showing layer inversion behavior, this simple mixing rule is capable of predicting the concentration of two species from the total solid concentration data of the bed.Corresponding Author: Dr. Mohammad Asif, Professor Department of Chemical Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh-11421, Saudi Arabia. Email: [email protected]

    Semantic Question Classification Datasets

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    This is the datasets used in the following paper:Can Taxonomy Help? Improving Semantic Question Matching using Question TaxonomyPaper: http://aclweb.org/anthology/C18-1042If you use the dataset please cite the following paper:@InProceedings{C18-1042, author = "Gupta, Deepak and Pujari, Rajkumar and Ekbal, Asif and Bhattacharyya, Pushpak and Maitra, Anutosh and Jain, Tom and Sengupta, Shubhashis", title = "Can Taxonomy Help? Improving Semantic Question Matching using Question Taxonomy", booktitle = "Proceedings of the 27th International Conference on Computational Linguistics", year = "2018", publisher = "Association for Computational Linguistics", pages = "499--513", location = "Santa Fe, New Mexico, USA", url = "http://aclweb.org/anthology/C18-1042" } </div

    Prediction of tool temperature during machining of Ti-6Al-4V alloy with atomization-based cutting fluid spray system

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    Atomization-based cutting fluid (ACF) spray system is being sought as an alternative to cooling processes currently used for machining difficult-to-cut materials such as Ti-6Al-4V alloy. The ACF spray system generates a stream of monodispersed droplets of cutting fluid which then gets mixed in a high-velocity gas flow to form a focused axisymmetric jet of droplets. During machining, this jet is able to penetrate the small region of the tool-chip interface helping in lubrication and cooling of the interface. The advantage of the ACF spray system is that it requires very small amount of cutting fluid, which makes the system more energy efficient and environmentally friendly. It has been recently reported that ACF spray system improves machining performances including tool life and reduced temperature near the tool-chip interface in turning Ti-alloy. It is clear from these studies that the reduction in temperature and improvement in machining are mainly dependent on the interaction of the cutting fluid from the ACF spray system with the chip-tool interface. Therefore, it is imperative to have a physics-based understanding of the phenomena taking place at the interface that is responsible for the tool temperature reduction. In this study, a thermal model for the atomization-based cutting fluid (ACF) spray system is developed to predict the temperature of the cutting edge of the tool during machining of titanium alloys. In the model, film boiling is taken into account because of the high temperatures involved in turning of Ti-6Al-4V alloy. Due to film boiling a thin vapor film is formed between the heated tool surface and the droplet. Heat is being conducted away from the tool through this film. It is shown that the thermal model is able to predict the temperature reduction due to ACF spray cooling and the predicted temperature profile is comparable to the experimental results.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2017-08-01The student, Asif Tanveer, accepted the attached license on 2015-07-24 at 11:26.The student, Asif Tanveer, submitted this Thesis for approval on 2015-07-24 at 11:34.This Thesis was approved for publication on 2015-07-24 at 12:56.DSpace SAF Submission Ingestion Package generated from Vireo submission #8643 on 2015-09-29 at 15:06:54Made available in DSpace on 2015-09-29T21:08:27Z (GMT). No. of bitstreams: 2 TANVEER-THESIS-2015.pdf: 5086790 bytes, checksum: 282d1e7303cadf265c50b5554666401f (MD5) LICENSE.txt: 4209 bytes, checksum: bd7acda06591d0aee5bc8c7fd43c53f5 (MD5) Previous issue date: 2015-07-24Embargo set by: Seth Robbins for item 89602 Lift date: 2017-09-29T21:08:35Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemLimited Restriction Lifted for Item 89602 on 2017-09-30T09:15:32Z

    Hydraulic simulations to evaluate and predict design and operation of the Chashma Right Bank Canal

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    Irrigation systems / Irrigation canals / Flow control / Velocity / Canal regulation techniques / Hydraulics / Simulation models / Design / Operations / Crop-based irrigation / Distributary canals / Water delivery / Policy / Protective irrigation / Water allocation / Water requirements / Sedimentation / Water distribution / Equity / Water conveyance / Pakistan / Chashma Right Bank Canal

    Tax systems in the reforming socialist economies of Europe

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    As socialist countries move toward market systems, fiscal policy is an important part of their reform agenda. First, they need to reorient public spending to focus more on the provision of"public"goods. Second, they need to adopt more selective, predictable, and nondiscretionary means to finance such spending. The goal of this paper is to lay out some of the broad trends and issues now emerging as socialist economies attempt to reform their systems of taxation. The primary focus is on Eastern Europe, although many of the same trends and issues arise in the reforming socialized countries of Asia and Africa. Particular attention is paid to Hungary and Poland, which are most advanced in the tax reform process. The experiences they have had and the problems they are facing provide valuable lessons for those countries just starting on the reform process.Public Sector Economics&Finance,Environmental Economics&Policies,Economic Theory&Research,Banks&Banking Reform,Municipal Financial Management
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