Miracle-dz/UniFAR-FTUs huggingface dataset:
Observability and observer design for switched linear systems

Johnson, Scott C. PhD, Purdue University, December 2016. Observability and Observer Design for Switched Linear Systems. Major Professor: Raymond DeCarlo. Hybrid vehicles, HVAC systems in new/old buildings, power networks, and the like require safe, robust control that includes switching the mode of operation to meet environmental and performance objectives. Such switched systems consist of a set of continuous-time dynamical behaviors whose sequence of operational modes is driven by an underlying decision process. This thesis investigates feasibility conditions and a methodology for state and mode reconstruction given input-output measurements (not including mode sequence). An application herein considers insulation failures in permanent magnet synchronous machines (PMSMs) used in heavy hybrid vehicles. Leveraging the feasibility literature for switched linear time-invariant systems, this thesis introduces two additional feasibility results: 1) detecting switches from safe modes into failure modes and 2) state and mode estimation for switched linear time-varying systems. This thesis also addresses the robust observability problem of computing the smallest structured perturbations to system matrices that causes observer infeasibility (with respect to the Frobenius norm). This robustness framework is sufficiently general to solve related robustness problems including controllability, stabilizability, and detectability. Having established feasibility, real-time observer reconstruction of the state and mode sequence becomes possible. We propose the embedded moving horizon observer (EMHO), which re-poses the reconstruction as an optimization using an embedded state model which relaxes the range of the mode sequence estimates into a continuous space. Optimal state and mode estimates minimize an L2-norm between the measured output and estimated output of the associated embedded state model. Necessary
Optimization of ReLU Neural Networks using Quotient Stochastic Gradient Descent

It has been well known that neural networks with rectified linear hidden units (ReLU) as activation functions are positively scale invariant, which results in severe redundancy in their weight space (i.e., many ReLU networks with different weights are actually equivalent). In this paper, we formally characterize this redundancy/equivalence using the language of \emph{quotient space} and discuss its negative impact on the optimization of ReLU neural networks. Specifically, we show that all equivalent ReLU networks correspond to the same vector in the quotient space, and each such vector can be characterized by the so-called skeleton paths in the ReLU networks. With this, we prove that the dimensionality of the quotient space is $\#$weight$-\#$(hidden nodes), indicating that the redundancy of the weight space is huge. In this paper, we propose to optimize ReLU neural networks directly in the quotient space, instead of the original weight space. We represent the loss function in the quotient space and design a new stochastic gradient descent algorithm to iteratively learn the model, which we call \emph{Quotient stochastic gradient descent } (abbreviated as Quotient SGD). We also develop efficient tricks to ensure that the implementation of Quotient SGD almost requires no extra computations as compared to standard SGD. According to the experiments on benchmark datasets, our proposed Quotient SGD can significantly improve the accuracy of the learned model.
Why does lexical selection have to be so hard? Comment on Abdel Rahman and Melinger's swinging lexical network proposal

The semantic interference effect, in the picture-word interference paradigm, has played an important role in the development of certain models of lexical selection. However, and aside from the semantic interference effect, the typical pattern that is observed when contrasting semantically related and unrelated distractors in the picture-word paradigm is facilitation. We have argued that semantic facilitation, and not semantic interference, is informative about the dynamics of lexical selection. Semantic interference in the picture-word interference paradigm arises at a post-lexical level of processing. Abdel Rahman and Melinger (2009 this issue) defend the hypothesis of lexical-selection-by-competition and argue that when the hypothesis is supplemented with additional assumptions, it can be reconciled with findings that are otherwise difficult to explain. Here we explore Abdel Rahman and Melinger's proposal. We argue that it is not clear that the authors have in fact succeeded in explaining the findings they set out to explain. In conclusion, we suggest that the liabilities of retaining the hypothesis of lexical-selection-by-competition outweigh the explanatory scope of that view.
Exploring the Relationship Between Corporate Goernance Mechanism and Financial Performance : Evidence From Listed Companies

This study examines, through quantitative analysis, the relationship between corporate governance practices and financial performance of a listed company in West Java, Indonesia. The research examines important financial performance measures, such as Return on Assets (ROA), Return on Equity (ROE), and Earnings per Share (EPS), using secondary data from annual reports, financial statements, and corporate governance disclosures. Various corporate governance practices are examined as independent variables, including board composition, ownership structure, CEO compensation, and audit quality. The study uses multiple regression analysis and correlation analysis to reveal significant associations between corporate governance practices and financial performance. The findings provide important insights for regulators, investors and business leaders to strengthen corporate governance standards and achieve long-term financial success in West Java's turbulent economic environment.
The impact of CDS trading on the bond market : evidence from Asia

This paper investigates the impact of CDS trading on the development of the bond market in Asia. In general, CDS trading has lowered the cost of issuing bonds and enhanced the liquidity in the bond market. The positive impact is stronger for smaller rms, non- nancial rms and those rms with higher liquidity in the CDS market. These empirical ndings support the diversi cation and information hypotheses in the literature. Nevertheless, CDS trading has also introduced a new source of risk. There is strong evidence that, at the peak of the recent global nancial crisis, those rms included in CDS indices faced higher bond yield spreads than those not included. Keywords: Credit default swaps, bond spreads, bond liquidity, CDS index, Asia. JEL Classi cation: G12, G32. We are grateful for comments by Jean Helwege, Michael King, Frank Packer, Eli Remolona and seminar participants at the Hong Kong Monetary Authority, the City University of Hong Kong and the Bank for International Settlements. We thank Clara Garcia, Jhuvesh Sobrun and Garry Tang for their excellent research assistance and Emma Claggett for language editing. The views presented here are solely those of the authors and do not necessarily represent those of the Bank for International Settlements. yBank for International Settlements. E-mail: ilhyock.shim@bis.org. zBank for International Settlements. E-mail: haibin.zhu@bis.org.
Household Decisions , Credit Markets and the Macroeconomy : Implications for the Design of Central Bank Models

This paper draws on research with Janine Aron (CSAE, Oxford), John Duca (Federal Reserve Bank, Dallas), Keiko Murata (Cabinet Office, Japan) and Anthony Murphy (Hertford College, Oxford). Earlier research support is acknowledged from the ESRC under “Improving Methods for Macro-econometric Modelling”, RES-000-23-0244 (with Adrian Pagan) and “New methods for forecasting inflation and its subcomponents”, RES-000-22-2066 (with Janine Aron). The author is grateful for comments from Janine Aron, Alan Bollard, Øystein Børsum, John Duca, Martin Ellison, Eilev Jansen, Richard Mash, Ragnar Nymoen, Rick van der Ploeg, David Vines and other participants at seminars in Oxford, at Statistics Norway, Oslo and at the BIS annual conference. The author is solely responsible for the views expressed.
Decentralisation and Quality of Fiscal Management: Empirical Evidence from Pakistan

Effective use of public resources is crucial for developing countries facing persistent deficits. Fiscal decentralisation is believed to enhance government efficiency over resource use. Therefore, the paper intends to examine the association between Pakistan’s Fiscal Decentralisation (FD) and Fiscal Management from 1988 to 2020. The authors develop a Composite Decentralisation Index (CDI) that captures the effect of both Expenditure Decentralisation (ED) and Revenue Decentralisation (RD) processes. After confirmation of stationarity through augmented Dickey-Fuller (ADF) and Philip-Peran (PP) unit roots tests, the study employs the Johansen cointegration method to draw longrun estimates. The study’s findings reveal that composite decentralisation reduces public deficit significantly - lower corruption, weaker underground economy, and smaller government size help reduce the fiscal deficit. The Error Correction Term (ECM) is also negative and significant at 1%, which confirms the speed of convergence towards longrun equilibrium in case of any shock or dis equilibrium in the short run. These study findings may help policymakers and legislatures draft effective long-term fiscal management policies.
FINDING EXPECTED REVENUES IN G-NETWORK WITH SIGNALS AND CUSTOMERS BATCH REMOVAL

The paper provides an analysis of G-network with positive customers and signals when signals arriving to the system move customer to another system or destroy in it a group of customers, reducing their number to a random value that is given by a probability distribution. The signal arriving to the system, in which there are no positive customers, does not exert any influence on the queueing network and immediately disappears from it. Streams of positive customers and signals arriving to each of the network systems are independent. Customer in the transition from one system to another brings the latest some revenue, and the revenue of the first system is reduced by this amount. A method of finding the expected revenues of the systems of such a network has been proposed. The case when the revenues from transitions between network states are deterministic functions depending on its states has been considered. A description of the network is given, all possible transitions between network states, transition probabilities, and revenues from state transitions are indicated. A system of difference-differential equations for the expected revenues of network systems has been obtained. To solve it, we propose a method of successive approximations, combined with the method of series. It is proved that successive approximations converge to the stationary solution of such a system of equations, and the sequence of approximations converges to a unique solution of the system. Each approximation can be represented as a convergent power series with an infinite radius of convergence, the coefficients of which are related by recurrence relations. Therefore, it is convenient to use them for calculations on a PC. The obtained results can be applied in forecasting losses in information and telecommunication systems and networks from the penetration of computer viruses into it and conducting computer attacks.
Comunicação no Ensino Exploratório: visão profissional de futuros professores de Matemática

Resumo O presente estudo tem como objetivo compreender a visão profissional sobre a comunicação no Ensino Exploratório desenvolvida por um grupo de futuros professores (FP) de Matemática numa disciplina da formação inicial. O contexto do estudo tem como elemento central a utilização de um caso multimídia que, dentre outras mídias, recorre ao vídeo para retratar episódios de uma aula de Matemática na perspectiva do Ensino Exploratório. Os dados dessa investigação qualitativa referem-se às respostas escritas dos FP em pequenos grupos e às discussões conjuntas nas sessões de formação voltadas à análise do caso. Os resultados evidenciam que os FP percebem os seguintes aspectos da comunicação: i) a promoção de interações dialógicas pela professora protagonista do caso para o desenvolvimento da tarefa matemática pelos alunos; e ii) o feedback da professora com base nas respostas dos alunos para o desenvolvimento da atividade matemática. O reconhecimento desses aspectos e os modos de raciocinar sobre eles expõem o desenvolvimento da visão profissional dos FP.
Dog cognitive development: A longitudinal study across the first two years of life

While our understanding of adult dog cognition has grown considerably over the past twenty years, relatively little is known about the ontogeny of dog cognition. To assess the development and longitudinal stability of cognitive traits in dogs, we administered a battery of tasks to 160 candidate assistance dogs at two timepoints. The tasks were designed to measure diverse aspects of cognition, ranging from executive function (e
Coriolis effect and the attachment of the leading edge vortex

The role of the Coriolis effect on the attachment of the leading edge vortex (LEV) is investigated. Toward that end, the Navier–Stokes equations are solved in the non-inertial reference frame of a high angle of attack $\unicode[STIX]{x1D6FC}$ rotating wing with the Coriolis term being artificially tuned. Reynolds numbers in the range $Re\in [100;750]$ are considered to identify the interplay between Coriolis and viscous effects. Similarly, artificial tuning of the centrifugal term is achieved to identify the interplay between Coriolis and centrifugal effects. It is shown that (i) the Coriolis effect is the key element in LEV stability for $Re>200$ , (ii) viscous effects are the key element for $Re<200$ and (iii) centrifugal effects have a marginal role. The Coriolis effect is found to promote spanwise flow in the core and behind the LEV, which is known to promote outboard vorticity transport and presumably contributes to stabilizing the aft boundary layer. These mechanisms of LEV stabilization have increased authority as $\unicode[STIX]{x1D6FC}$ decreases.
First international comparison of primary absorbed dose to water standards in the medium-energy X-ray range

This report presents the results of the first international comparison of primary measurement standards of absorbed dose to water for the medium-energy X-ray range. Three of the participants (VSL, PTB, LNE-LNHB) used their existing water calorimeter based standards and one participant (ENEA) recently developed a new standard based on a water-graphite calorimeter. The participants calibrated three transfer chambers of the same type in terms of absorbed dose to water (N Dw) and in addition in terms of air kerma (NK ) using the CCRI radiation qualities in the range 100 kV to 250 kV. The additional NK values were intended to be used for a physical analysis of the ratios N Dw/NK . All participants had previously participated in the BIPM.RI(I)-K3 key comparison of air kerma standards. Ratios of pairs of NMI's NK results of the current comparison were found to be consistent with the corresponding key comparison results within the expanded uncertainties of 0.6 % - 1 %. The N Dw results were analysed in terms of the degrees of equivalence with the comparison reference values which were calculated for each beam quality as the weighted means of all results. The participant's results were consistent with the reference value within the expanded uncertainties. However, these expanded uncertainties varied significantly and ranged between about 1-1.8 % for the water calorimeter based standards and were estimated at 3.7 % for the water-graphite calorimeter. It was shown previously that the ratios N Dw/NK for the type of ionization chamber used as transfer chamber in this comparison were very close (within less than 1 %) to the calculated values of (μ̄en/ρ)w,a d, the mean values of the water-to-air ratio of the mass-energy-absorption coefficients at the depth d in water. Some of the participant's results deviated significantly from the expected behavior. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm. org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Bifurcation analysis of landing gear shimmy using flexible multibody models

Shimmy oscillations are undesired vibrations in aircraft landing gears. The onset of shimmy, marked by Hopf bifurcations, is investigated in the parameter space of an industrial, high-fidelity, flexible multibody landing gear model. The bifurcation analyses are performed by coupling the Virtual.Lab Motion multibody solver with the numerical continuation software AUTO. The resulting quasi-2-parameter bifurcation diagrams, involving aircraft velocity and vertical landing gear load, are verified using conventional time-domain simulations and are shown to guarantee significantly higher solution accuracy at a similar computational cost.
Symmetry and Variational Analyses of Fluid Interface Equations in the Thin Film Limit

This thesis concerns a class of nonlinear partial differential equations up to fourth order in spatial derivatives that models thin viscous films. In Chapter 1, we review the derivations of thin film equations from the fundamental transport equations. Section 1.1 contains the derivation for a thermocapillary driven film to familiarize the reader with the key long-wavelength approximation that has been successful in modeling a myriad of thin viscous films. In Section 1.2, we consider the coupling between a thin viscous layer and a much thicker fluid layer with much larger viscosity and conductivity and show how a novel, non-local thermocapillary thin film equation can be derived to model such a system. We then review the wider class of thin film equations in Section 1.3, note the important Cahn-Hilliard variational form of these equations, and demonstrate that classic mathematical results concerning the inverse problem of the calculus of variations permit an algorithmic procedure for discovering Lyapunov functionals. In Chapter 2, we review applications of symmetry methods to partial differential equations. Section 2.1 contains an original geometrical motivation for the study of self-similar reductions which draws an analogy with the fixed points of dynamical systems. In Section 2.2, we derive for the first time the full set of symmetries of the fully two-dimensional thin film equations. We then enumerate the possible symmetry reductions of the thin film equations, and discover several which have not been previously recognized. In Chapter 3, we consider rotationally invariant, steady droplet solutions and their stability. In Section 3.1, we derive stability criteria for thermocapillary-driven droplets, and show a novel correspondence between droplet stability, droplet volume, and droplet Lyapunov energy. We consider thin films under other forces in Section 3.2 and make new predictions about conditions under which such films develop into droplets, columns, or jets of fluid. In Chapter 4, we consider the scale invariant symmetry reductions of thin film equations. In Section 4.1 we describe the extraordinarily rich variety of such solutions in the spreading of a insoluble surfactant on a thin viscous film, identify previously unrecognized scale invariant solutions which are well-behaved at the origin, and demonstrate their relevance with finite element simulations. Lastly, in Section 4.2, we illustrate for capillary driven films some numerical solutions to the novel reductions we uncovered in Chapter 2. Each chapter concludes with a Notes section which summarizes the new results contained therein and relates them to the wider literature.
SHORT-TERM COASTAL LANDSCAPE EVOLUTION IN CIREBON BAY USING COASTLINE ENVIRONMENT ANALYSIS

The landscape of Java’s north coast is dominated by a mild slope covered by soft sediment, which faces many environmental issues. These issues have been identified, and the simple technique of overlaying Landsat imagery shows the evolution of the landscape along the coast. Survey campaigns in 2006 and 2018 verified the Landsat overlay, and the 210Pb dating analysis aids in describing the sedimentation rate along the coast. The results demonstrate that accretion evolution dominates exclusively in Cirebon’s coastline landscape, with coastal gains reaching 1463.88 ha over four decades and the sediment rate from 1977–1997 estimated at 0.27–0.33 cm/year. Compared to the earlier decade, the recent two periods from 1998 to 2018 demonstrate a more extensive desire for progressive accretion affected by the longshore sediment transport. Hence, special attention should be paid to the northern coast of Java to estimate the sedimentation rate and the advanced coast.
Microscale mapping of SPAD photon detection probability

As silicon photomultiplier (SiPM) technology still has potential for further improvements, we describe a method to map the photon detection probability of a single-photon avalanche diode (SPAD) at the microscale level, in order to evaluate the behavior of the SPAD triggering capabilities as a function of the position of the incident light and to determine its homogeneity. For this purpose, we performed the analysis of the light response for a single active SPAD, with all its neighbors switched off, using a scanning setup, composed of the digital SiPM SPADnet-I data acquisition system, a microscope, a servo positioning system, a spectrograph and a CCD camera. We varied the wavelength of the incoming light to probe the device volume from the P-well to the N-well, with the ultimate goal of understanding and improving overall sensor performance. The comparison of this study to SPAD design and electric field technology computer-aided design (TCAD) simulation enables one to estimate how much the P-well drawn area could be increased to optimize fill factor without causing premature edge breakdown through guard ring failure.
Counseling the Unemployed: Does it Lower Unemployment Duration and Recurrence?

This article evaluates the effects of intensive counseling schemes that are provided to about 20% of the unemployed since the 2001 French unemployment policy reform (PARE). Several of the schemes are dedicated at improving the quality of assignment of workers to jobs. As a result, it is necessary to assess their impact on unemployment recurrence as well as unemployment duration. Using duration models and a very rich data set, we can identify heterogenous and time-dependent causal effects of the schemes. We find significant favorable effects on both outcomes, but the impact on unemployment recurrence is stronger than on unemployment duration. In particular, the program shifts the incidence of recurrence, one year after employment, from 33 to 26%. This illustrates that labor market policies evaluations that consider unemployment duration alone can be misleading.