Letteratura scientifica selezionata sul tema "Finite gain theory"
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Articoli di riviste sul tema "Finite gain theory"
1
Cavaleri, Matteo, e Alfredo Donno. "On cospectrality of gain graphs". Special Matrices 10, n. 1 (1 gennaio 2022): 343–65. http://dx.doi.org/10.1515/spma-2022-0169.
Testo completoAbstract (sommario):
Abstract We define G G -cospectrality of two G G -gain graphs ( Γ , ψ ) \left(\Gamma ,\psi ) and ( Γ ′ , ψ ′ ) \left(\Gamma ^{\prime} ,\psi ^{\prime} ) , proving that it is a switching isomorphism invariant. When G G is a finite group, we prove that G G -cospectrality is equivalent to cospectrality with respect to all unitary representations of G G . Moreover, we show that two connected gain graphs are switching equivalent if and only if the gains of their closed walks centered at an arbitrary vertex v v can be simultaneously conjugated. In particular, the number of switching equivalence classes on an underlying graph Γ \Gamma with n n vertices and m m edges, is equal to the number of simultaneous conjugacy classes of the group G m − n + 1 {G}^{m-n+1} . We provide examples of G G -cospectral switching nonisomorphic graphs and we prove that any gain graph on a cycle is determined by its G G -spectrum. Moreover, we show that when G G is a finite cyclic group, the cospectrality with respect to a faithful irreducible representation implies the cospectrality with respect to any other faithful irreducible representation, and that the same assertion is false in general.
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Mattos, Lucas Prado, Manuel Ernani Cruz e Julián Bravo-Castillero. "Finite element computation of the effective thermal conductivity of two-dimensional multi-scale heterogeneous media". Engineering Computations 35, n. 5 (2 luglio 2018): 2107–23. http://dx.doi.org/10.1108/ec-11-2017-0444.
Testo completoAbstract (sommario):
Purpose The simulation of heat conduction inside a heterogeneous material with multiple spatial scales would require extremely fine and ill-conditioned meshes and, therefore, the success of such a numerical implementation would be very unlikely. This is the main reason why this paper aims to calculate an effective thermal conductivity for a multi-scale heterogeneous medium. Design/methodology/approach The methodology integrates the theory of reiterated homogenization with the finite element method, leading to a renewed calculation algorithm. Findings The effective thermal conductivity gain of the considered three-scale array relative to the two-scale array has been evaluated for several different values of the global volume fraction. For gains strictly above unity, the results indicate that there is an optimal local volume fraction for a maximum heat conduction gain. Research limitations/implications The present approach is formally applicable within the asymptotic limits required by the theory of reiterated homogenization. Practical implications It is expected that the present analytical-numerical methodology will be a useful tool to aid interpretation of the gain in effective thermal conductivity experimentally observed with some classes of heterogeneous multi-scale media. Originality/value The novel aspect of this paper is the application of the integrated algorithm to calculate numerical bulk effective thermal conductivity values for multi-scale heterogeneous media.
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Sharma, Anshul, C. K. Susheel, Rajeev Kumar e V. S. Chauhan. "Active Control of Thermally Induced Vibrations in Smart Structure Instrumented with Piezoelectric Materials". Applied Mechanics and Materials 612 (agosto 2014): 169–74. http://dx.doi.org/10.4028/www.scientific.net/amm.612.169.
Testo completoAbstract (sommario):
In this paper, a finite element model of piezolaminated composite shell structure is developed using nine-noded degenerated shell element. The stiffness, mass and thermo-electro-mechanical coupling effect is incorporated in finite element modeling using first order shear deformation theory and linear piezoelectric theory. The sensor voltage is calculated using the same formulation and fuzzy logic controller is used to calculate the actuator voltage. The fuzzy logic controller is designed as double input-single output (DISO) system using 49 If-Then rules. The performance of fuzzy logic controller is compared with convention constant-gain negative feedback controller. The simulation results illustrate the superiority of fuzzy logic controller over constant-gain negative feedback controller.
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Zhao, Zhanshan, Xiaomeng Li, Jing Zhang e Yongzhen Pei. "Terminal sliding mode control with self-tuning for coronary artery system synchronization". International Journal of Biomathematics 10, n. 03 (20 febbraio 2017): 1750041. http://dx.doi.org/10.1142/s1793524517500413.
Testo completoAbstract (sommario):
A terminal sliding mode (TSM) control with self-tuning gain algorithm is proposed for the synchronization of coronary artery system under the existence of the unmodeled dynamics and the external disturbance. Considering the sliding mode dynamics of system, a criterion of selecting the parameters is derived to reach the point of equilibrium in the finite time. The theoretic analysis based on Lyapunov theory proved that the systems with the proposed TSM control with self-tuning scheme could be stabilized in finite time. The proposed method shows that the drive and response systems are synchronized and states of the response system track the states of the drive system in finite time. This information about the bound of unmodeled dynamics and the external disturbance is not needed in advance through self-tuning the gains of controller. The results for coronary artery system synchronization simulation show that the proposed TSM controller with self-tuning achieves better robustness and adaptation against unmodeled dynamics and the external disturbance, which offer the theory basis on curing myocardial infarction.
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Deng, Xiongfeng, Yiqing Huang e Lisheng Wei. "Adaptive Fuzzy Command Filtered Finite-Time Tracking Control for Uncertain Nonlinear Multi-Agent Systems with Unknown Input Saturation and Unknown Control Directions". Mathematics 10, n. 24 (8 dicembre 2022): 4656. http://dx.doi.org/10.3390/math10244656.
Testo completoAbstract (sommario):
This paper investigates the finite-time consensus tracking control problem of uncertain nonlinear multi-agent systems with unknown input saturation and unknown control directions. An adaptive fuzzy finite-time consensus control law is proposed by combining the fuzzy logic system, command filter, and finite-time control theory. Using the fuzzy logic systems, the uncertain nonlinear dynamics are approximated. Considering the command filter and backstepping control technique, the problem of the so-called “explosion of complexity” in the design of virtual control laws and adaptive updating laws is avoided. Meanwhile, the Nussbaum gain function method is applied to handle the unknown control directions and unknown input saturation problems. Based on the finite-time control theory and Lyapunov stability theory, it was found that all signals in the closed-loop system remained semi-global practical finite-time stable, and the tracking error could converge to a sufficiently small neighborhood of the origin in the finite time. In the end, simulation results were provided to verify the validity of the designed control law.
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Zhang, Xin Yu, e Li Kun Guan. "Stress Analysis and Structure Improvement on Arm of Ladle Turret". Applied Mechanics and Materials 597 (luglio 2014): 336–40. http://dx.doi.org/10.4028/www.scientific.net/amm.597.336.
Testo completoAbstract (sommario):
Static stress analysis on arm of ladle turret is based on finite element (FE) theory and shell theory by finite element software ANSYS. In this paper, an arm subjected to a multi-axial state of stress is examined both numerically and experimentally. The hot spot strains and stresses in the connection are determined through a detailed finite element analysis (FEA) of the joint. The arm geometry is accurately modeled using FE. Check the dangerous position on the side of the arm by different safety factor. For the experimental study, a test rig is designed and used to validate the FE model. Gain the impact factor of the arm. According to finite element calculations, assesses the fatigue strength by stress ratio method and stress amplitude method on the weld.Structural improvement is performed with increasing thickness and changing the location of the force.
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Brandt, Bastian B., Gergely Endrődi e Sebastian Schmalzbauer. "QCD at finite isospin chemical potential". EPJ Web of Conferences 175 (2018): 07020. http://dx.doi.org/10.1051/epjconf/201817507020.
Testo completoAbstract (sommario):
We investigate the properties of QCD at finite isospin chemical potential at zero and non-zero temperatures. This theory is not affected by the sign problem and can be simulated using Monte-Carlo techniques. With increasing isospin chemical potential and temperatures below the deconfinement transition the system changes into a phase where charged pions condense, accompanied by an accumulation of low modes of the Dirac operator. The simulations are enabled by the introduction of a pionic source into the action, acting as an infrared regulator for the theory, and physical results are obtained by removing the regulator via an extrapolation. We present an update of our study concerning the associated phase diagram using 2+1 flavours of staggered fermions with physical quark masses and the comparison to Taylor expansion. We also present first results for our determination of the equation of state at finite isospin chemical potential and give an example for a cosmological application. The results can also be used to gain information about QCD at small baryon chemical potentials using reweighting with respect to the pionic source parameter and the chemical potential and we present first steps in this direction.
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Ma, Xin, e Fang Zhu. "Prescribed Performance Synchronization Control of Chaotic Systems with Unknown Control Gain Signs". Journal of Control Science and Engineering 2021 (23 luglio 2021): 1–7. http://dx.doi.org/10.1155/2021/5160768.
Testo completoAbstract (sommario):
For a class of uncertain nonlinear chaotic systems with unknown control gain signs and saturated input, by means of Nussbaum function, a scheme of finite-time prescribed performance synchronization control is proposed. Here, Nussbaum function is used to eliminate the influence of unknown control gain signs, and fuzzy logic systems are used to estimate unknown functions. Lyapunov theory is used to prove that all synchronization errors converge to a predefined small performance range under the designed control method. Finally, simulation results are provided to illustrate the feasibility of the proposed method.
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Zhang, Chao, Qiang Guo e Jing Wang. "Finite-Time Synchronizing Control for Chaotic Neural Networks". Abstract and Applied Analysis 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/938612.
Testo completoAbstract (sommario):
This paper addresses the finite-time synchronizing problem for a class of chaotic neural networks. In a real communication network, parameters of the master system may be time-varying and the system may be perturbed by external disturbances. A simple high-gain observer is designed to track all the nonlinearities, unknown system functions, and disturbances. Then, a dynamic active compensatory controller is proposed and by using the singular perturbation theory, the control method can guarantee the finite-time stability of the error system between the master system and the slave system. Finally, two illustrative examples are provided to show the effectiveness and applicability of the proposed scheme.
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Jian, Xiong, Zengyun Wang, Aitong Xin, Yujing Chen e Shujuan Xie. "An improved finite-time stabilization of discontinuous non-autonomous IT2 T-S fuzzy interconnected complex-valued systems: A fuzzy switching state-feedback control method". Electronic Research Archive 31, n. 1 (2022): 273–98. http://dx.doi.org/10.3934/era.2023014.
Testo completoAbstract (sommario):
<abstract><p>Based on the type-2 Takagi-Sugeno (IT2 T-S) fuzzy theory, a non-autonomous fuzzy complex-valued dynamical system with discontinuous interconnection function is formulated. Under the framework of Filippov, the finite-time stabilization (FTS) problem is investigated by using an indefinite-derivative Lyapunov function method, where the derivative of the constructed Lyapunov function is allowed to be positive. By designing a fuzzy switching state feedback controller involving time-varying control gain parameters, several sufficient criteria are established to determine the considered system's stability in finite time. Correspondingly, due to the time-varying system parameters and the designed time-dependent control gain coefficients, a more flexible settling time (ST) is estimated. Finally, an example is presented to confirm the proposed methodology.</p></abstract>
Tesi sul tema "Finite gain theory"
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Dong, Shijie, of Western Sydney Hawkesbury University e Faculty of Science and Technology. "Robust nonlinear process control by L2 finite gain theory". THESIS_FST_XXX_Dong_S.xml, 1998. http://handle.uws.edu.au:8081/1959.7/386.
Testo completoAbstract (sommario):
This thesis focuses on nonlinear robust process control synthesis and analysis. The theoretical fundamental is the L2 finite gain theory. The aim of this research is to gain better understanding of this theory and develop new process control synthesis and analysis methods for nonlinear processes with model uncertainties and unmeasured disturbances.The current nonlinear process control methods are examined in this thesis. The research scopes of this study are described as follows: 1/. To characterize the most common process control problems such as zero-offset requirement, presentation of model uncertainties and unknown disturbance in the L2 finite gain theory framework and solve the basic theoretical issues concerned in controller design. 2/. To solve numerical computation problems arising in the nonlinear controller. 3/. To investigate the relationship between robustness requirement and performance requirement for nonlinear systems in the L2 finite gain theory framework. 4/. To consider the common phenomenon such as time-delay in the new developed methods. 5/. To investigate the advantages of the controller based on the L2 finite gain theory over the current nonlinear control methods. A series of new systematic robust process control synthesis approaches are the main contributions of this study. Simulations show the potential of these newly developed methods.Doctor of Philosophy (PhD)
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Dong, Shijie. "Robust nonlinear process control by L2 finite gain theory". Thesis, [Richmond, N.S.W.] : Faculty of Science and Technology, University of Western Sydney Hawkesbury, 1998. http://handle.uws.edu.au:8081/1959.7/386.
Testo completoAbstract (sommario):
This thesis focuses on nonlinear robust process control synthesis and analysis. The theoretical fundamental is the L2 finite gain theory. The aim of this research is to gain better understanding of this theory and develop new process control synthesis and analysis methods for nonlinear processes with model uncertainties and unmeasured disturbances.The current nonlinear process control methods are examined in this thesis. The research scopes of this study are described as follows: 1/. To characterize the most common process control problems such as zero-offset requirement, presentation of model uncertainties and unknown disturbance in the L2 finite gain theory framework and solve the basic theoretical issues concerned in controller design. 2/. To solve numerical computation problems arising in the nonlinear controller. 3/. To investigate the relationship between robustness requirement and performance requirement for nonlinear systems in the L2 finite gain theory framework. 4/. To consider the common phenomenon such as time-delay in the new developed methods. 5/. To investigate the advantages of the controller based on the L2 finite gain theory over the current nonlinear control methods. A series of new systematic robust process control synthesis approaches are the main contributions of this study. Simulations show the potential of these newly developed methods.
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Dong, Shijie. "Robust nonlinear process control by L2 finite gain theory : a thesis submitted in fulfillment of the requirements for the degree of doctor of philosophy /". [Richmond, N.S.W.] : Faculty of Science and Technology, University of Western Sydney Hawkesbury, 1998. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030520.122605/index.html.
Testo completo
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Li, Yunyan. "Global finite-time observers for a class of nonlinear systems". Thesis, University of Pretoria, 2013. http://hdl.handle.net/2263/40825.
Testo completoAbstract (sommario):
The contributions of this thesis lie in the area of global finite-time observer design for a class of
nonlinear systems with bounded rational and mixed rational powers imposed on the incremental rate
of the nonlinear terms whose solutions exist and are unique for all positive time. In the thesis, two
different kinds of nonlinear global finite-time observers are designed by employing of finite-time
theory and homogeneity properties with different methods. The global finite-time stability of both
proposed observers is derived on the basis of Lyapunov theory.
For a class of nonlinear systems with rational and mixed rational powers imposed on the nonlinearities,
the first global finite-time observers are designed, where the global finite-time stability of the
observation systems is achieved from two parts by combining asymptotic stability and local finitetime
stability. The proposed observers can only be designed for the class of nonlinear systems with
dimensions greater than 3. The observers have a dynamic high gain and two homogenous terms, one
homogeneous of degree greater than 1 and the other of degree less than 1. In order to prove the global
finite-time stability of the proposed results, two homogeneous Lyapunov functions are provided, corresponding
with the two homogeneous items. One is homogeneous of degree greater than 1, which
makes the observation error systems converging into a spherical area around the origin, and the other
is of degree less than 1, which ensures local finite-time stability.
The second global finite-time observers are also proposed based on the high-gain technique, which
does not place any limitation on the dimension of the nonlinear systems. Compared with the first
global finite-time observers, the newly designed observers have only one homogeneous term and a
new gain update law where two new terms are introduced to dominate some terms in the nonlinearities
and ensure global finite-time stability as well. The global finite-time stability is obtained directly
based on a sufficient condition of finite-time stability and only one Lyapunov function is employed in
the proof.
The validity of the two kinds of global finite-time observers that have been designed is illustrated through some simulation results. Both of them can make the observation error systems converge to
the origin in finite-time. The parameters, initial conditions as well as the high gain do have some
impact on the convergence time, where the high gain plays a stronger role. The bigger the high gain
is, the shorter the time it needs to converge. In order to show the performance of the two kinds of
observers more clearly, two examples are provided and some comparisons are made between them.
Through these, it can be seen that under the same parameters and initial conditions, although the
amplitude of the observation error curve is slightly greater, the global finite-time observers with a
new gain update law can make the observation error systems converge much more quickly than the
global finite-time observers with two homogeneous terms. In the simulation results, one can see that,
as a common drawback of high gain observers, they are noise-sensitive. Finding methods to improve
their robustness and adaptiveness will be quite interesting, useful and challenging.Thesis (PhD)--University of Pretoria, 2013.
gm2014
Electrical, Electronic and Computer Engineering
unrestricted
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Daniyan, Abdullahi. "Advanced signal processing techniques for multi-target tracking". Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/35277.
Testo completoAbstract (sommario):
The multi-target tracking problem essentially involves the recursive joint estimation of the state of unknown and time-varying number of targets present in a tracking scene, given a series of observations. This problem becomes more challenging because the sequence of observations is noisy and can become corrupted due to miss-detections and false alarms/clutter. Additionally, the detected observations are indistinguishable from clutter. Furthermore, whether the target(s) of interest are point or extended (in terms of spatial extent) poses even more technical challenges. An approach known as random finite sets provides an elegant and rigorous framework for the handling of the multi-target tracking problem. With a random finite sets formulation, both the multi-target states and multi-target observations are modelled as finite set valued random variables, that is, random variables which are random in both the number of elements and the values of the elements themselves. Furthermore, compared to other approaches, the random finite sets approach possesses a desirable characteristic of being free of explicit data association prior to tracking. In addition, a framework is available for dealing with random finite sets and is known as finite sets statistics. In this thesis, advanced signal processing techniques are employed to provide enhancements to and develop new random finite sets based multi-target tracking algorithms for the tracking of both point and extended targets with the aim to improve tracking performance in cluttered environments. To this end, firstly, a new and efficient Kalman-gain aided sequential Monte Carlo probability hypothesis density (KG-SMC-PHD) filter and a cardinalised particle probability hypothesis density (KG-SMC-CPHD) filter are proposed. These filters employ the Kalman- gain approach during weight update to correct predicted particle states by minimising the mean square error between the estimated measurement and the actual measurement received at a given time in order to arrive at a more accurate posterior. This technique identifies and selects those particles belonging to a particular target from a given PHD for state correction during weight computation. The proposed SMC-CPHD filter provides a better estimate of the number of targets. Besides the improved tracking accuracy, fewer particles are required in the proposed approach. Simulation results confirm the improved tracking performance when evaluated with different measures. Secondly, the KG-SMC-(C)PHD filters are particle filter (PF) based and as with PFs, they require a process known as resampling to avoid the problem of degeneracy. This thesis proposes a new resampling scheme to address a problem with the systematic resampling method which causes a high tendency of resampling very low weight particles especially when a large number of resampled particles are required; which in turn affect state estimation. Thirdly, the KG-SMC-(C)PHD filters proposed in this thesis perform filtering and not tracking , that is, they provide only point estimates of target states but do not provide connected estimates of target trajectories from one time step to the next. A new post processing step using game theory as a solution to this filtering - tracking problem is proposed. This approach was named the GTDA method. This method was employed in the KG-SMC-(C)PHD filter as a post processing technique and was evaluated using both simulated and real data obtained using the NI-USRP software defined radio platform in a passive bi-static radar system. Lastly, a new technique for the joint tracking and labelling of multiple extended targets is proposed. To achieve multiple extended target tracking using this technique, models for the target measurement rate, kinematic component and target extension are defined and jointly propagated in time under the generalised labelled multi-Bernoulli (GLMB) filter framework. The GLMB filter is a random finite sets-based filter. In particular, a Poisson mixture variational Bayesian (PMVB) model is developed to simultaneously estimate the measurement rate of multiple extended targets and extended target extension was modelled using B-splines. The proposed method was evaluated with various performance metrics in order to demonstrate its effectiveness in tracking multiple extended targets.
Libri sul tema "Finite gain theory"
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Brink, David O., Susan Sauvé Meyer e Christopher Shields, a cura di. Virtue, Happiness, Knowledge. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198817277.001.0001.
Testo completoAbstract (sommario):
Fifteen leading philosophers explore a set of themes from the pioneering work of Gail Fine and Terence Irwin, in ancient philosophy but also in later periods and in systematic philosophy. The contributors discuss knowledge, rhetoric, freedom and practical reason, virtue and the good life, ethics and politics in Plato and Aristotle and beyond. The editors offer an introduction charting the scholarly contributions of Fine and Irwin and assessing their individual and joint impact, together with a complete bibliography of their writings. This volume is a token of our immense gratitude to Gail Fine and Terry Irwin for the benefit we have derived from their penetrating scholarly work. Through their writing, their teaching, their mentoring, and their broader scholarly output, Gail Fine and Terry Irwin have reshaped the character of Ancient Philosophy as an academic discipline. Their contributions to the discipline do not, however, end there. On the contrary, their wide-ranging achievements extend into all periods of the history of philosophy and indeed into several areas more systematic than historical.
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Idris, Murad. Assigning Symmetry. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190658014.003.0002.
Testo completoAbstract (sommario):
Chapter 1 examines peace and war in Plato’s Laws. The dialogue’s speakers schematize war along an aesthetic pattern of symmetry, of polis against polis, person against person. These wars suggest an orderly universe. Ultimately, they locate peace in a different aesthetic—namely, the wholeness of the polis. The characters’ generalization of the polis as the primary site of well-ordered peace and war reflects anxieties about the polis’s finitude and about sources of disordering violence, notably Greek empires, Persia, and slave revolts. Second, Plato has his characters rehabilitate peace against arguments about its insufficiency by affirming that “war is for the sake of peace” and by appealing to peace’s parasitical structure: they insinuate fraternity, friendship, unity, security, and law into peace. In both Plato’s Laws and contemporaneous Athenian orations, these insinuates gain primacy over peace and facilitate war, including wars that govern the polis’s interior and police its surrounding neighbors.
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Brink, David O., Susan Sauvé Meyer e Shields Christopher, a cura di. Introduction. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198817277.003.0001.
Testo completoAbstract (sommario):
Through their writing, their teaching, their mentoring, and their broader scholarly output, Gail Fine and Terry Irwin have reshaped the character of ancient philosophy as an academic discipline. Their contributions to the discipline do not, however, end there. On the contrary, their wide-ranging achievements extend into all periods of the history of philosophy and indeed into several areas more systematic than historical. Or perhaps one should say, rather, that their work defies any ready classification as being either historical or systematic, because whatever its primary focus on a given occasion, what they write cannot be pigeonholed as either exclusively scholarly or thematic; for they practice an unremittingly philosophical form of history of philosophy, or, judged from another angle, a historically enriched form of systematic philosophy. That is, as they pursue it, philosophy engages the discipline’s history in a manner animated by its current and perennial concerns, but it does so while remaining fully sensitive to the original context of its production. Their work combines the highest level of scholarly rigor and rich philosophical insight. Animated by a purely philosophical spirit, it is never narrowly antiquarian in orientation. Although alert to matters of text and transmission reflecting painstaking philological care and exceptionally broad scholarly erudition, their work never loses sight of a simple question: should we too believe this?...
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Kaufmann, Liane, Karin Kucian e Michael von Aster. Development of the numerical brain. A cura di Roi Cohen Kadosh e Ann Dowker. Oxford University Press, 2014. http://dx.doi.org/10.1093/oxfordhb/9780199642342.013.008.
Testo completoAbstract (sommario):
This article focuses on typical trajectories of numerical cognition from infancy all the way through to adulthood (please note that atypical pathways of numerical cognition will be dealt in‘Brain Correlates of Numerical Disabilities’). Despite the fact that developmental imaging studies are still scarce to date there is converging evidence that (1) neural signatures of non-verbal number processing may be observed already in infants; and (2) developmental changes in neural responsivity are characterized by increasing functional specialization of number-relevant frontoparietal brain regions. It has been suggested that age and competence-related modulations of brain activity manifest as an anterior-posterior shift. On the one hand, the recruitment of supporting frontal brain regions decreases, while on the other hand, reliance on number-relevant (fronto-)parietal neural networks increases. Overall, our understanding of the neurocognitive underpinnings of numerical development grew considerably during the last decade. Future research is expected to benefit substantially from the fast technological advances enabling researchers to gain more fine-grained insights into the spatial and temporal dynamics of the neural signatures underlying numerical development.
Capitoli di libri sul tema "Finite gain theory"
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Solis, Cesar U., e Julio B. Clempner. "Finite-Time Sliding Mode Controller with State-Dependent Gain Parameter". In New Perspectives and Applications of Modern Control Theory, 317–33. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62464-8_13.
Testo completo
2
Hedman, Shawn. "Finite model theory". In A First Course in Logic. Oxford University Press, 2004. http://dx.doi.org/10.1093/oso/9780198529804.003.0014.
Testo completoAbstract (sommario):
This final chapter unites ideas from both model theory and complexity theory. Finite model theory is the part of model theory that disregards infinite structures. Examples of finite structures naturally arise in computer science in the form of databases, models of computations, and graphs. Instead of satisfiability and validity, finite model theory considers the following finite versions of these properties. • A first-order sentence is finitely satisfiable if it has a finite model. • A first-order sentence is finitely valid if every finite structure is a model. Finite model theory developed separately from the “classical” model theory of previous chapters. Distinct methods and logics are used to analyze finite structures. In Section 10.1, we consider various finite-variable logics that serve as useful languages for finite model theory. We define variations of the pebble games introduced in Section 9.2 to analyze the expressive power of these logics. Pebble games are one of the few tools from classical model theory that is useful for investigating finite structures. In Section 10.2, it is shown that many of the theorems from Chapter 4 are no longer true when restricted to finite models. There is no analog for the Completeness and Compactness theorems in finite model theory. Moreover, we prove Trakhtenbrot’s theorem which states that the set of finitely valid first-order sentences is not recursively enumerable. Descriptive complexity is the subject of 10.3. This subject describes the complexity classes discussed in Chapter 7 in terms of the logics introduced in Chapter 9. We prove Fagin’s theorem relating the class NP to existentional second-order logic. We prove the Cook–Levin theorem as a consequence of Fagin’s Theorem. This theorem states that the Satisfiability Problem for Propositional Logic is NP-complete. We conclude this chapter (and this book) with a section describing the close connection between logic and the P = NP problem. In this section, we discuss appropriate logics for the study of finite models. First-order logic, since it describes each finite model up to isomorphism, is too strong. For this reason, we must weaken the logic. It may seem counter-intuitive that we should gain knowledge by weakening our language.
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Davidson, Michael. "Cleavings". In Invalid Modernism, 167–80. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198832812.003.0008.
Testo completoAbstract (sommario):
Using poems by Emily Dickinson and recent work in cultural and queer theory, this final chapter explores the fine line between “gain” and “loss” in disability studies. Using the author’s own experience of gradual hearing loss, the chapter argues that recent claims for the positive values of “deaf gain” through the use of American Sign Language have vaunted possibilities of cultural inclusiveness to the exclusion of affective realms of frustration, loss, and failure that are seldom acknowledged experiences of deaf and hard-of-hearing persons. While endorsing the general thrust of Deaf Gain and its implications for the larger context of disability, the chapter argues for a more critical understanding of loss in the politics of gain.
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Guirao, Fernando. "Finale". In The European Rescue of the Franco Regime, 1950-1975, 433–40. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198861232.003.0010.
Testo completoAbstract (sommario):
The Nine failed to establish an industrial free-trade area with Spain and thus to gain access to the Spanish market, the largest west European industrial market outside their direct influence. The decision of the Council of Ministers of the European Communities, in October 1975, to suspend FTA negotiations with Spain, without denouncing the 1970 Agreement, meant the ultimate success of the Spanish government’s politico-economic strategy, the last episode of the European rescue of the Franco regime. The EC Council decision might have been inevitable in terms of public opinion and democratic morality, but it meant to permit Madrid to retain full control over the country’s import policy while fully exploiting the export prospects offered by the 1970 Agreement. In the end, the decision was detrimental for the overall interests of all the parties involved, whether the Spanish population or Western Europe. The final section of this book invites economic historians to estimate the costs of the Spanish EEC policy concerning the inefficient allocation of resources, weak technological transfer, lesser accompanying investment, and limitations to total-factor-productivity increases. Political historians, in turn, should explore what specific interests explain, in each case, why, if official Spanish trade practices in export promotion and import restriction gave the Six every incentive to denounce the 1970 Agreement, apart from obvious political reasons, they did not do so. Finally, scholars dealing with Spanish EEC-membership negotiations should determine the extent at which the Community experience over the 1970 Agreement explains Community attitudes towards some Spanish demands after 1979.
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Izquierdo-Córdoba, Luis Miguel, João Maurício Rosário e Darío Amaya Hurtado. "Hybrid Dynamic Modelling and Bioinspired Control Based on Central Pattern Generator of Biped Robotic Gait". In Advanced Robotics and Intelligent Automation in Manufacturing, 233–68. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1382-8.ch009.
Testo completoAbstract (sommario):
This chapter presents the theoretical foundations and methodology to develop a bioinspired hybrid control architecture for a biped robotic device that reproduces gait and human motor control strategies with the ability to adapt the trajectory to environmental conditions. The objective is to design robotic devices (such as exoskeletons), through the functional integration of hybrid dynamic system modeling (event-driven and continuous dynamics) with efficient and robust conventional control techniques and bioinspired control algorithms, with a near-natural human gait pattern. The human gait cycle is modeled as a hybrid dynamic using a finite state machine (FSM). The gait trajectories are to be generated in such a way that they will be capable of adapting to disturbances in the path followed by the robotic device; this will be achieved using a neuronal oscillator that simulates the behavior of a central pattern generator (CPG).
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Goyal, Mukta, e Chetna Gupta. "Intuitionistic Fuzzy Decision Making Towards Efficient Team Selection in Global Software Development". In Research Anthology on Agile Software, Software Development, and Testing, 1756–75. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-3702-5.ch084.
Testo completoAbstract (sommario):
For successful completion of any software project, an efficient team is needed. This task becomes more challenging when the project is to be completed under global software development umbrella. The manual selection of team members based on some expert judgment may lead to inappropriate selection. In reality, there are hundreds of employees in an organization and a single expert may be biased towards any member. Thus, there is a need to adopt methods which consider multiple selection criteria with multiple expert views for making appropriate selection. This article uses an intuitionistic fuzzy approach to handle uncertainty in the expert's decision in multicriteria group decision making process and ranking among the finite team members. An intuitionistic fuzzy Muirhead Mean (IFMM) is used to aggregate the intuitionistic criteria's. To gain confidence between criteria and expert score relationship, the Annova test is performed. The results are promising with p value as small as 0.02 and one-tail t-test score equals to 0.0000002.
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Xia, Xiang-Gen, Genyuan Wang e Pingyi Fan. "Space-Time Modulated Codes for MIMO Channels with Memory". In Handbook on Advancements in Smart Antenna Technologies for Wireless Networks, 130–55. IGI Global, 2009. http://dx.doi.org/10.4018/978-1-59904-988-5.ch007.
Testo completoAbstract (sommario):
Modulated codes (MC) are error correction codes (ECC) defined on the complex field and therefore can be naturally combined with an intersymbol interference (ISI) channel. It has been previously proved that for any finite tap ISI channel there exist MC with coding gain comparing to the uncoded AWGN channel. In this chapter, we first consider space-time MC for memory channels, such as multiple transmit and receive antenna systems with ISI. Similar to MC for single antenna systems, the space-time MC can be also naturally combined with a multiple antenna system with ISI, which provides the convenience of the study. Some lower bounds on the capacities C and the information rates Ii.i.d of the MC coded systems are presented. We also introduce an MC coded zero-forcing decision feedback equalizer (ZF-DFE) where the channel is assumed known at both the transmitter and the receiver. The optimal MC design based on the ZF-DFE are presented.
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Cobanoglu, Ozden. "The Incidence of Ovulation and Detection of Genes Associated with Ovulation and Twinning Rates in Livestock". In Bovine Science [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99936.
Testo completoAbstract (sommario):
Cattle is a monotocous species that generally produce only one offspring per conception. However, multiple ovulations are a naturally emerging reproductive phenomenon typically controlled by genetic structure and environmental factors. On the other hand, few genes or causative mutations might explain significant genetic variations between animals for the reproductive traits. Studies report different methods, including QTL analysis, fine mapping, GWAS, and MAS selection, to improve such traits due to their economic importance. The recent fine-mapping study, which narrows the genomic region, indeed, influencing multiple ovulation, gives positive signals that causative mutation controlling high ovulation rate may be identified shortly. In conclusion, identifying the major genes that considerably affect ovulation and twinning rates provides the opportunity to increase reproduction efficiency by improving genetic gain in livestock species.
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R., Maheswari, Pattabiraman Venkatasubbu e A. Saleem Raja. "Gait Analysis Using Principal Component Analysis and Long Short Term Memory Models". In Structural and Functional Aspects of Biocomputing Systems for Data Processing, 79–97. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-6523-3.ch004.
Testo completoAbstract (sommario):
Human analysis and diagnosis have become attractive technology in many fields. Gait defines the style of movement and gait analysis is a study of human activity to inspect the style of movement and related factors used in the field of biometrics, observation, diagnosis of gait disease, treatment, rehabilitation, etc. This work aims in providing the benefit of analysis of gait with different sensors, ML models, and also LSTM recurrent neural network, using the latest trends. Placing the sensors at the proper location and measuring the values using 3D axes for these sensors provides very appropriate results. With proper fine-tuning of ML models and the LSTM recurrent neural network, it has been observed that every model has an accuracy of greater than 90%, concluding that LSTM performance is observed to be slightly higher than machine learning models. The models helped in diagnosing the disease in the foot (if there is injury in the foot) with high efficiency and accuracy. The key features are proven to be available and extracted to fit the LSTM RNN model and have a positive outcome.
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Rajendran, R., e K. Vivekanandan. "Exploring Relationship between Information Systems Strategic Orientation and Small Business Performance". In Electronic Business, 1764–79. IGI Global, 2009. http://dx.doi.org/10.4018/978-1-60566-056-1.ch110.
Testo completoAbstract (sommario):
Businesses invest in developing information systems resources to gain competitive advantages. Literature has demonstrated the requirement of strategic alignment in converting these competitive advantages into sustained superior business performance. The knowledge of information systems strategic orientation and its relationship with business performance will enable these businesses to fine tune their strategic information systems applications portfolio in achieving required strategic alignment. This study focuses on the information systems strategic orientation of small businesses and investigates its relationship with their perceived business performance. The organizational impact of adoption of the initial stages of electronic business development is also examined. The data were collected from small businesses on nine strategy areas, through mail survey. The result reveals three multifaceted dimensions of information systems strategic orientation. These dimensions of strategic orientation have significantly influenced their business performance. For the adopters of Web presence, all these three dimensions remain significant in explaining their business performance.
Atti di convegni sul tema "Finite gain theory"
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Centurelli, Francesco, Pietro Monsurro e Alessandro Trifiletti. "An MDAC architecture with low sensitivity to finite opamp gain". In 2011 European Conference on Circuit Theory and Design (ECCTD). IEEE, 2011. http://dx.doi.org/10.1109/ecctd.2011.6043597.
Testo completo
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Yeliseyeva, N. P., S. L. Berdnik, V. A. Katrich e M. V. Nesterenko. "Directive gain of horizontal impedance vibrator located over finite-size perfectly conducting screen". In 2015 XXth IEEE International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED). IEEE, 2015. http://dx.doi.org/10.1109/diped.2015.7324255.
Testo completo
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Yeilaghi-Tamijani, A., R. Mirzaeifar, A. R. Ohadi e M. R. Eslami. "Vibration Control of FGM Plate With Piezoelectric Sensors and Actuators Using Higher Order Shear Deformation Theory". In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95710.
Testo completoAbstract (sommario):
In this paper, finite element formulation for the active control of functionally graded material (FGM) plates containing piezoelectric sensor/actuator patches by using higher order shear deformation theory is carried out. The major difference to previous studies is the new feedback control algorithm for active control of FGM plate which is presented in this paper. The effects of the configuration of the S/A pairs and the velocity and displacement feedback control gains on the static and dynamic response of the structure are studied. Numerical results are presented for the static deflection, natural frequency and dynamic control of FGM plate in both tabular and graphical forms. The result obtained by using new feedback control algorithm show that peak responses can be controlled by the displacement control gain and active damping can be provided by adjusting the velocity control gain. The model without feedback control is validated by comparing with existing results in the literature.
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Kee, Daniel De, e Ning Sun. "Prediction of Stress Jump and Elongational Viscosity via Network Theory". In ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-1987.
Testo completoAbstract (sommario):
Abstract The network model, originally developed for rubber like materials and later extended to model liquids, is subject to modifications. In this work, we look at the adaptation for improved elongational viscosity predictions and to allow for stress jump predictions. A new formulation involving non-affine motion is proposed and its applications are presented. The major improvement is that a finite elongational viscosity is predicted for finite elongational rate, contrary to infinite elongational viscosities existing at some elongational rates predicted by most previous network models. Comparisons with experimental data on shear viscosity, primary normal stress coefficient and elongational viscosity are given, in terms of the same set of model parameters. The model is successfully tested with data on a polyisobutylene solution (S1). A further extension of the network model is related to the prediction of the stress jump phenomenon which is defined as the instantaneous gain or loss of stress on startup or cessation of flow. It is not predicted by most existing models. In this work, the internal viscosity idea used in the dumbbell model is incorporated into the transient network model. Via appropriate approximations, a closed form constitutive equation, which predicts a stress jump, is obtained. Successful comparisons with the available stress jump measurements are given. In addition, the model yields good quantitative predictions of the standard steady and dynamic material functions, for xanthan solutions and for Polyacrylamide solutions.
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Chang, C. S., e Herbert U. Fluhler. "Implications of self-consistent QED to high voltage XUV free electron lasers". In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.wt3.
Testo completoAbstract (sommario):
A self-consistent quantum electrodynamic (SCQED) theory of high voltage free electron lasers (FEL) is given. Spontaneous emission spectra and gain are predicted in the small signal gain regime and compared to FEL experimental data. The SCQED theory predicts line shift, spectral broadening, and gain reduction due to quantum mechanical effects which are not predicted by the classical/conventional FEL theories. Comparison with well accepted FEL experiments shows excellent agreement between the SCQED predictions and the data: much better than predicted by the classical/conventional FEL theories. Classical FEL theory is recovered as a subset of the SCQED theory in the classical limit of the SCQED FEL theory. It is found that the classical/conventional FEL theories are only valid in the limit of a short undulator containing a small number of periods. This limit results from the non-negligible finite electron state lifetime, and its associated spectral linewidth broadening (natural linewidth phenomena).
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Masri, Karim M., Mohammad I. Younis e Shuai Shao. "Investigation of a Delayed Feedback Controller of MEMS Resonators". In ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/detc2013-12045.
Testo completoAbstract (sommario):
Controlling mechanical systems is an important branch of mechanical engineering. Several techniques have been used to control Microelectromechanical systems (MEMS) resonators. In this paper, we study the effect of a delayed feedback controller on stabilizing MEMS resonators. A delayed feedback velocity controller is implemented through modifying the parallel plate electrostatic force used to excite the resonator into motion. A nonlinear single degree of freedom model is used to simulate the resonator response. Long time integration is used first. Then, a finite deference technique to capture periodic motion combined with the Floquet theory is used to capture the stable and unstable periodic responses. We show that applying a suitable positive gain can stabilize the MEMS resonator near or inside the instability dynamic pull in band. We also study the stability of the resonator by tracking its basins of attraction while sweeping the controller gain and the frequency of excitations. For positive delayed gains, we notice significant enhancement in the safe area of the basins of attraction.
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Naseradinmousavi, Peiman, C. Nataraj e Matthew Frank. "Nonlinear Modeling and Analysis of Electromagnetic Bearings With Permanent Magnets for Bias". 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/detc2012-71311.
Testo completoAbstract (sommario):
This article describes high fidelity modeling of electromagnetic (EM) bearings with permanent magnets (PM) used to supply bias current. We analyze both the PM and EM parts of the system. Magnetic circuit theory is first used to gain insight into the magnetic forces and allows for the dynamic analysis of a rigid rotor coupled with the magnetic bearings. The results reveal that the magnetic forces are a strong nonlinear function of the rotor offsets from its equilibrium position. Next, the validity of the simplifying assumptions is examined with the aid of the finite element method. Comparisons of the magnetic forces are presented and discussed.
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Patel, Jay, e Pedro Peralta. "Mechanisms for Kink Band Evolution in Polymer Matrix Composites: A Digital Image Correlation and Finite Element Study". In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-67482.
Testo completoAbstract (sommario):
Polymer matrix composites (PMCs) are attractive structural materials due to their high stiffness and low weight to strength ratio. However, unidirectional PMCs have low shear strength and failure can occur along kink bands that develop on compression due to plastic microbuckling that carry strains large enough to induce nonlinear matrix deformation. The study of kink band nucleation and evolution in unidirectional composites (UDCs) is an active area of research. In the last five decades, a large body of research has been done to understand kink band mechanisms using theory and experiments. However, a large fraction of the existing work is for uniaxial compression. The effects of stress gradients, such as those present during bending, have not been as well explored, and these effects are bound to make difference in terms of kink band nucleation and growth. Furthermore, reports on experimental measurements of strain fields leading to and developing inside these bands in the presence of stress gradients are also scarce. This need to be addressed to gain a full understanding of their behavior when UDCs are used under bending and other spatially complex stress states, particularly given that the compressive strength of these composites is a function of stress-gradient. Therefore, the primary focus of this work is to understand mechanisms for kink band evolution under an influence of stress-gradients induced during bending. Digital image correlation (DIC) is used to measure strains inside and around the kink bands during 3-point bending of samples with 0°/90° stacking made of Dyneema HB80, a trademark of DSM. Measurements indicate bands nucleate at the compression side and propagate into the sample carrying a mixture of large shear and normal strains, while also decreasing its bending stiffness. Failure was produced by a combination of plastic microbuckling and axial splitting. The microstructure of the kink bands was studied and used in a microstructurally explicit finite element model (FEM). It has been used to analyze stresses and strains at ply level in the samples during kink band evolution, using cohesive zone elements to represent the interfaces between plies. Cohesive element properties were deduced by a combination of delamination, fracture and three-point bending tests used to calibrate the FEMs. Modeling results show that progressive buckling of plies leads to kink band nucleation and propagation and that the band morphology is sensitive to the shear and opening properties of the interfaces between the plies.
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Kersken, Hans-Peter, Christian Frey, Christian Voigt e Graham Ashcroft. "Time-Linearized and Time-Accurate 3D RANS Methods for Aeroelastic Analysis in Turbomachinery". In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22940.
Testo completoAbstract (sommario):
A computational method for performing aeroelastic analysis using either a time-linearized or an unsteady time-accurate solver for the compressible Reynolds averaged Navier-Stokes (RANS) equations is described. The time-linearized solver employs the assumption of small time-harmonic perturbations and is implemented via finite differences of the nonlinear flux routines of the time-accurate solver. The resulting linear system is solved using a parallelized Generalized Minimal Residual (GMRES) method with block-local preconditioning. The time accurate solver uses a dual time stepping algorithm for the solution of the unsteady RANS equations on a periodically moving computational grid. For either solver, and both flutter and forced response problems, a mapping algorithm has been developed to map structural eigenmodes, obtained from finite element structural analysis, from the surface mesh of the finite element structural solver to the surface mesh of the finite volume flow solver. Using the surface displacement data an elliptic mesh deformation algorithm, based on linear elasticity theory, is then used to compute the grid deformation vector field. The developed methods are validated first using standard configuration ten. Finally, for an ultra high bypass ratio fan the results of the time-linearized and the unsteady module are compared. The gain in prediction time using the linearized methods is highlighted.
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Shirani, Farhad, e S. Sandeep Pradhan. "Finite block-length gains in distributed source coding". In 2014 IEEE International Symposium on Information Theory (ISIT). IEEE, 2014. http://dx.doi.org/10.1109/isit.2014.6875124.
Testo completoRapporti di organizzazioni sul tema "Finite gain theory"
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Patel, Reena. Complex network analysis for early detection of failure mechanisms in resilient bio-structures. Engineer Research and Development Center (U.S.), giugno 2021. http://dx.doi.org/10.21079/11681/41042.
Testo completoAbstract (sommario):
Bio-structures owe their remarkable mechanical properties to their hierarchical geometrical arrangement as well as heterogeneous material properties. This dissertation presents an integrated, interdisciplinary approach that employs computational mechanics combined with flow network analysis to gain fundamental insights into the failure mechanisms of high performance, light-weight, structured composites by examining the stress flow patterns formed in the nascent stages of loading for the rostrum of the paddlefish. The data required for the flow network analysis was generated from the finite element analysis of the rostrum. The flow network was weighted based on the parameter of interest, which is stress in the current study. The changing kinematics of the structural system was provided as input to the algorithm that computes the minimum-cut of the flow network. The proposed approach was verified using two classical problems three- and four-point bending of a simply-supported concrete beam. The current study also addresses the methodology used to prepare data in an appropriate format for a seamless transition from finite element binary database files to the abstract mathematical domain needed for the network flow analysis. A robust, platform-independent procedure was developed that efficiently handles the large datasets produced by the finite element simulations. Results from computational mechanics using Abaqus and complex network analysis are presented.
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Riveros, Guillermo, Felipe Acosta, Reena Patel e Wayne Hodo. Computational mechanics of the paddlefish rostrum. Engineer Research and Development Center (U.S.), settembre 2021. http://dx.doi.org/10.21079/11681/41860.
Testo completoAbstract (sommario):
Purpose – The rostrum of a paddlefish provides hydrodynamic stability during feeding process in addition to detect the food using receptors that are randomly distributed in the rostrum. The exterior tissue of the rostrum covers the cartilage that surrounds the bones forming interlocking star shaped bones. Design/methodology/approach – The aim of this work is to assess the mechanical behavior of four finite element models varying the type of formulation as follows: linear-reduced integration, linear-full integration, quadratic-reduced integration and quadratic-full integration. Also presented is the load transfer mechanisms of the bone structure of the rostrum. Findings – Conclusions are based on comparison among the four models. There is no significant difference between integration orders for similar type of elements. Quadratic-reduced integration formulation resulted in lower structural stiffness compared with linear formulation as seen by higher displacements and stresses than using linearly formulated elements. It is concluded that second-order elements with reduced integration and can model accurately stress concentrations and distributions without over stiffening their general response. Originality/value – The use of advanced computational mechanics techniques to analyze the complex geometry and components of the paddlefish rostrum provides a viable avenue to gain fundamental understanding of the proper finite element formulation needed to successfully obtain the system behavior and hot spot locations.
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Yahav, Shlomo, John Brake e Orna Halevy. Pre-natal Epigenetic Adaptation to Improve Thermotolerance Acquisition and Performance of Fast-growing Meat-type Chickens. United States Department of Agriculture, settembre 2009. http://dx.doi.org/10.32747/2009.7592120.bard.
Testo completoAbstract (sommario):
: The necessity to improve broiler thermotolerance and performance led to the following hypothesis: (a) thethermoregulatory-response threshold for heat production can be altered by thermal manipulation (TM) during incubation so as to improve the acquisition of thermotolerance in the post-hatch broiler;and (b) TM during embryogenesis will improve myoblast proliferation during the embryonic and post-hatch periods with subsequent enhanced muscle growth and meat production. The original objectives of this study were as follow: 1. to assess the timing, temperature, duration, and turning frequency required for optimal TM during embryogenesis; 2. to evaluate the effect of TM during embryogenesis on thermoregulation (heat production and heat dissipation) during four phases: (1) embryogenesis, (2) at hatch, (3) during growth, and (4) during heat challenge near marketing age; 3. to investigate the stimulatory effect of thermotolerance on hormones that regulate thermogenesis and stress (T₄, T₃, corticosterone, glucagon); 4. to determine the effect of TM on performance (BW gain, feed intake, feed efficiency, carcass yield, breast muscle yield) of broiler chickens; and 5. to study the effect of TM during embryogenesis on skeletal muscle growth, including myoblast proliferation and fiber development, in the embryo and post-hatch chicks.This study has achieved all the original objectives. Only the plasma glucagon concentration (objective 3) was not measured as a result of technical obstacles. Background to the topic: Rapid growth rate has presented broiler chickens with seriousdifficulties when called upon to efficiently thermoregulate in hot environmental conditions. Being homeotherms, birds are able to maintain their body temperature (Tb) within a narrow range. An increase in Tb above the regulated range, as a result of exposure to environmental conditions and/or excessive metabolic heat production that often characterize broiler chickens, may lead to a potentially lethal cascade of irreversible thermoregulatory events. Exposure to temperature fluctuations during the perinatal period has been shown to lead to epigenetic temperature adaptation. The mechanism for this adaptation was based on the assumption that environmental factors, especially ambient temperature, have a strong influence on the determination of the “set-point” for physiological control systems during “critical developmental phases.” In order to sustain or even improve broiler performance, TM during the period of embryogenesis when satellite cell population normally expand should increase absolute pectoralis muscle weight in broilers post-hatch. Major conclusions: Intermittent TM (39.5°C for 12 h/day) during embryogenesis when the thyroid and adrenal axis was developing and maturing (E7 to E16 inclusive) had a long lasting thermoregulatory effect that improved thermotolerance of broiler chickens exposed to acute thermal stress at market age by lowering their functional Tb set point, thus lowering metabolic rate at hatch, improving sensible heat loss, and significantly decreasing the level of stress. Increased machine ventilation rate was required during TM so as to supply the oxygen required for the periods of increased embryonic development. Enhancing embryonic development was found to be accomplished by a combination of pre-incubation heating of embryos for 12 h at 30°C, followed by increasing incubation temperature to 38°C during the first 3 days of incubation. It was further facilitated by increasing turning frequency of the eggs to 48 or 96 times daily. TM during critical phases of muscle development in the late-term chick embryo (E16 to E18) for 3 or 6 hours (39.5°C) had an immediate stimulatory effect on myoblast proliferation that lasted for up to two weeks post-hatch; this was followed by increased hypertrophy at later ages. The various incubation temperatures and TM durations focused on the fine-tuning of muscle development and growth processes during late-term embryogenesis as well as in post-hatch chickens.