877 research outputs found
A robust semi-definite optimization based solution to the robust order reduction problem for parametric uncertain dissipative linear systems
No full textIn this paper we address the problem of reducing the order of a linear
system affected by uncertainties from the robust dissipative perspective introduced in Barb. Firstly, we show that all major balanced truncation techniques developed and reported in the literature of the last two decades see Enns, Glover, Moore, Harshavardhana, Jonckheere, Opdenacker, Phillips) can be treated in a uniform fashion within the framework of dissipative systems. Accordingly, we shall generalize these
results to uncertain dissipative systems.
The key role is played by balancing two positive definite robust solutions to the uncertain dissipativity LMIs associated with the linear system in question and its dual. Determining the maximal level of uncertainty for which such two solutions exists and computing them efficiently is well known to be NP-hard. Our method is based on determining robust tractable approximations of these NP-hard entities by following the
novel method known as Matrix-Cube Theory. The proven results are accompanied by a numerical example
Evaluation of CAN-FD Protocol for Traffic Signalling
No full textU ovom diplomskom radu je evaluiran CAN-FD protokol u svrhu upravljanja prometnom signalizacijom. Naglasak je stavljen na ispitivanje karakteristika protokola u realnim uvjetima te je zbog toga razvijen elektronički modul koji simulira funkcionalnosti LED modula čijim kaskadiranjem se dobiva promjenjivi prometni znak veće površine. Opisane su razlike između CAN 2.0B i CAN-FD protokola te su opisane funkcije pojedinih okvira u jednom CAN-FD paketu. U poglavljima koji se tiču razvoja programske podrške je opisano kako se konfiguriraju generatori signala takta te osnovne inicijalizacije sustava, kao i verifikacija pojedinih segmenata programskog koda. Osim razvoja sklopovlja i programske podrške pokazan je i način odabira adekvatnog mikrokontrolera u smislu karakteristika, kućišta te cijene.In this master thesis author evaluated new CAN-FD communications protocol for use in controlling dynamic traffic signs. Protocol testing was done on a custom made embedded system that simulates the funcionality of a real LED module used in dynamic signs. The differences between CAN-FD and CAN2.0B and the functions are described in the third chapter. Clock configuration and system initialization are described in the chapters regarding development of a software solution for this system as well as testing individual code segments to verify their functionality. In addition to the development of hardware and software this thesis also considers the selection of an adequate microcontroller in terms of characteristics, package and price
Regulation FD: SEC Reestablishes Enforcement Capabilities over Selective Disclosure.
No full textThis Recent Development focuses on the potential effects Regulation Fair Disclosure (FD) will have on the participants in the American capital market and on the stock markets themselves. Congress and the Securities Exchange Commission (SEC) seek to achieve confidence in the integrity and fairness of the American stock market and protection of investors from fraud by promoting equal opportunities for investors. In order to maintain a competitive edge, vis-à-vis its foreign counterparts, the United States must continually refine its financial systems to maximize fairness and integrity. This Recent Development focuses on selective disclosure—allowing a limited segment of investors access to information about a company’s financial performance—along with the inability of existing securities regulations to prohibit such practices. The recently promulgated Regulation FD is a measure anticipated to reign in the disclosure of nonpublic information to a privileged few. Specific requirements within the Regulation FD are examined by the author, and the SEC intends for the Regulation FD to level the playing field for investors. Furthermore, this Recent Development addresses potential trouble areas caused by the regulation’s interplay with other securities rules and regulations. In addition to suggestions for compliance, the various touchstones of controversy such as the effects related to Regulation FD on the securities industry are also discussed. Regulation FD molds a remedy to the perceived evils of selective disclosure. Confidentiality agreements represent the SEC’s strategy for controlling selective disclosure, without expressly authorizing it. This Recent Development concludes with an assessment of the practical effects that Regulation FD will have on the securities industry and the likelihood that it is here to stay
A Millimeter-Wave Front-End for FD/FDD Transceivers Featuring an Embedded PA and an N-Path Filter Based Circulator Receiver
No full textThis work presents an ultra-compact single-antenna FD/FDD transceivers front-end. It comprises a nonreciprocal circulator, RX, and an integrated power amplifier (PA). In the proposed circulator, we devise a ring quarter-wave transmission line topology with adjusted characteristic impedances to improve TX-to-antenna insertion loss and TX-to-RX isolation. Besides, an AND-gate switching-based N-path filter is proposed to realize the circulator's nonreciprocal gyrator while acting as a mixer-first RX. Owing to the ultra-compact N-path filter structure, the circulator occupies only 0.38mm 2 core area. Over a 27.1-to-31.1GHz band, the realized front-end offers >20dB TX-to-RX isolation while its measured TX-to-antenna insertion loss is 1.7~2.2dB. The RX path tolerates the PA's blocker signal, achieving 5dBm in-band and 13dBm out-of-band B 1dB. Moreover, the PA delivers 15.15dBm peak output power with 33% drain efficiency. Our front-end prototype occupies only 0.7mm 2 , including circulator, PA, quadrature hybrid coupler LO generators, and baseband circuits.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic
() Jackknife results for the PD- and FD- libraries: yellow squares indicate hits detected from the PD- library, blue squares indicate hits detected from the FD- library and green squares indicate hits detected from both the libraries
No full text<p><b>Copyright information:</b></p><p>Taken from "Detecting DNA-binding helix–turn–helix structural motifs using sequence and structure information"</p><p>Nucleic Acids Research 2005;33(7):2129-2140.</p><p>Published online 14 Apr 2005</p><p>PMCID:PMC1079965.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> Incorrectly aligned hits are highlighted with slashes and crosses: forward slashes (/) indicate incorrectly aligned hits detected from the FD- library, backward slashes (\) indicate incorrectly aligned hits detected from the PD- library and crosses (X) indicate incorrectly aligned hits detected from both the libraries. () Jackknife results for the combination of PD- and FD- libraries and the method of 3D-templates. Green squares indicate hits detected from either the FD- library or the PD- library or both; red squares indicate hits detected from the method of 3D-templates; and brown squares indicate hits detected from all the three methods
Risk of screening adherence by category of FD practices.
No full textA. FDs (the markers correspond to the practice baricenter and marker colors to adherence category) plotted against SARs for small triangular areas (about 0.50 km2). B. Top panel: crude adherence rates (left) and (right) by FD practices. Bottom panel: marginal predicted adherence probability for low adherence FDs and high participation FDs and, for comparison, adherence probability for a generic person at average level of covariates. Figure was created by the author Bianconi F. combing the caterpillar, bar plots and maps generate with GeCO-sys an extension of [21].</p
Estimating the fundamental diagram using moving observers
No full textThe fundamental diagram (FD) describes the relation between the flow and density in equilibrium conditions. In this paper, we propose an estimation approach to estimate the FD based on data from moving observers. This approach consists of two main steps: (1) estimate flow and density for space-time areas based on trajectories of moving observers and the times and locations they are overtaken or being overtaken and (2) estimate the FD based on the fflow,densityg-estimates. To evaluate and gain a deeper understanding of the proposed approach, a simulation study was conducted. This study shows that the fflow,densityg-estimates provide valuable information to estimate the FD. Furthermore, the FDs belonging to the simulated traffic flow are estimated accurately. We realize that the second step is expected to be less accurate for traffic that behaves stochastic. Therefore, we provide a potential solution path to extend the second step in future work.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Transport and PlanningTransport and Plannin
Application-Layer Anomaly Detection Leveraging Time-Series Physical Semantics in CAN-FD Vehicle Networks
No full textData Availability Statement:
The data presented in this study are available on request from the corresponding author. The data are not publicly available due to the need for confidentiality of application layer protocols for car companies.The Controller Area Network with Flexible Data-Rate (CAN-FD) bus is the predominant in-vehicle network protocol, responsible for transmitting crucial application semantic signals. Due to the absence of security measures, CAN-FD is vulnerable to numerous cyber threats, particularly those altering its authentic physical values. This paper introduces Physical Semantics-Enhanced Anomaly Detection (PSEAD) for CAN-FD networks. Our framework effectively extracts and standardizes the genuine physical meaning features present in the message data fields. The implementation involves a Long Short-Term Memory (LSTM) network augmented with a self-attention mechanism, thereby enabling the unsupervised capture of temporal information within high-dimensional data. Consequently, this approach fully exploits contextual information within the physical meaning features. In contrast to the non-physical semantics-aware whole frame combination detection method, our approach is more adept at harnessing the physical significance inherent in each segment of the message. This enhancement results in improved accuracy and interpretability of anomaly detection. Experimental results demonstrate that our method achieves a mere 0.64% misclassification rate for challenging-to-detect replay attacks and zero misclassifications for DoS, fuzzing, and spoofing attacks. The accuracy has been enhanced by over 4% in comparison to existing methods that rely on byte-level data field characterization at the data link layer.National Natural Science Foundation of China under Grants 52202494 and 52202495
Partitioned FSI strategy for simulations of a thin elastic valve
No full textWe present a Fictitious Domain (FD)/Lagrange multiplier method to approximate a thin valve movement immersed in an incompressible fluid. We developed a partitioned FSI algorithm that is able to keep the fluid and structure codes independent and which involve only minor modifications to each one . We propose a quantitative comparison between FD and ALE, when the displacement is moderated. We show that the two approaches give results in good agreement. We also illustrate FD in a simulation involving very large displacements
A Meshfree RBF-FD Constant along Normal Method for Solving PDEs on Surfaces
No full textThis paper introduces a novel meshfree methodology based on radial basis function-finite difference (RBF-FD) approximations for the numerical solution of partial differential equations (PDEs) on surfaces of codimension 1 embedded in R3. The method is built upon the principles of the closest point method, without the use of a grid or a closest point mapping. We show that the combination of local embedded stencils with these principles can be employed to approximate surface derivatives using polyharmonic spline kernels and polynomials (PHS + Poly) RBF-FD. Specifically, we show that it is enough to consider a constant extension along the normal direction only at a single node to overcome the rank deficiency of the polynomial basis. An extensive parameter analysis is presented to test the dependence of the approach. We demonstrate high-order convergence rates on problems involving surface advection and surface diffusion, and solve Turing pattern formations on surfaces defined either implicitly or by point clouds. Moreover, a simple coupling approach with a particle tracking method demonstrates the potential of the proposed method in solving PDEs on evolving surfaces in the normal direction. Our numerical results confirm the stability, flexibility, and high-order algebraic convergence of the approach.The work of the first author has received support from the Madrid government (Comunidad de Madrid-Spain) under the Multiannual Agreement with UC3M (H2SAFE-CM-UC3M). The second author has been partially supported by the State of Upper Austria. The fourth author has been partially supported by the Natural Sciences and Engineering Research Council of Canada (RGPIN 2022-03302)
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