Robust limit on a varying proton-to-electron mass ratio from a single H2 system

The variation of the dimensionless fundamental physical constant mu=m_p/m_e can be checked through observation of Lyman and Werner lines of molecular hydrogen in the spectra of distant QSOs. Our intention is to asses the accuracy of the investigation concerning a possible variation of mu and to provide more robust results for QSO 0347-383. The goal in mind is to resolve the current controversy on variation of mu and devise explanations for the different findings. We achieve this not by another single result but by providing alternative approaches to the problem. An analysis based on independent data sets of QSO 0347-383 is put forward and new approaches for some of the steps involved in the data analysis are introduced. We analyse two independent sets of observations of the same absorption system and for the first time we apply corrections for the observed offsets between discrete spectra Drawing on two independent observations of a single absorption system in QSO 0347-383 our detailed analysis yields dmu/mu = 15 +/- (9_stat + 6_sys) x 10^{-6} at z_abs=3.025. Based on the overall goodness-of-fit we estimate the limit of accuracy to about 300 m/s, consisting of roughly 180 m/s due to the uncertainty of the fit and about 120 m/s allocated to systematics This work presents alternative approaches to handle systematics and introduces methods required for precision analysis of QSO spectra available in the near future.Comment: 9 pages, 10 figures, submitted to A&

New CFAR algorithm and circuit development for radar receiver

Automatic target detection radar requires adaptive thresholding achieved by the Constant False Alarm Rate (CFAR) circuit to control the false alarm caused by variations in the background clutter. This thesis deal with the problem that happened when an abrupt variation in background clutter merged with a multi-interfering target, and when the clutter cloud itself centered with multi-interfering targets. To detect targets in such environments, it needs a robust CFAR algorithm that excises the target spikes and clutter edges from the CFAR window to give the best possible estimation of the noise background. The Maximum Spike Subtraction MSS-CFAR family that uses two lock circuits to find two maximum spikes in the CFAR window that subtracted from sample summing to make better background noise estimation that used to construct an adaptive threshold. The MSS-CFAR family is MSS-CA�CFAR, MSS-GO-CFAR, and MSS-SO-CFAR, MSS-CFAR family in addition to two core algorithms were studied which are cell averaged CA-CFAR family that includes the greatest of GO-CFAR and smallest of SO-CFAR and ordered statistics OS-CFAR family that include greatest of ordered statistics OSGO-CFAR and the smallest of ordered statistics OSSO-CFAR. All these algorithms are simulated using MATLAB and applied them to three different clutter models that represent different environment cases. The CA-CFAR family failed to handle models two and three also OS-CFAR family except for OS-CFAR that handle all models successfully. For the MSS-CFAR family, MSS-CA-CFAR could handle all models successfully, and comparing with OS-CFAR, the MSS-CA-CFAR need less hardware and processing time because it did not need a sorting process that is essential for OS-CFAR. Therefore, the MSS-CA-CFAR is chosen to implement by practical digital circuit and there is another important feature in the MSS-CFAR algorithm that is parallel processing since the spike selection process is done at the same time with summing of samples process that makes this algorithm much less in processing time from any other algorithm using the same environment. The last MATLAB test for MSS-CA- vi CFAR with a spiky exponential model shown in Table 4.3 in chapter four shows clearly that MSS-CA-CFAR detects nine targets from ten that means the efficiency of detection of the proposed method is 90%. The field-programmable gate array FPGA chip that is used to implement the MSS-CA-CFAR algorithm needs only three signals from the radar receiver to match with the receiver circuit correctly which are time base clock signal period reset trigger signal and the pulse duration time

Adaptation and Fatigue Model for Neuron Networks and Large Time Asymptotics in a Nonlinear Fragmentation Equation

International audienceMotivated by a model for neural networks with adaptation and fatigue, we study a conservative fragmentation equation that describes the density probability of neurons with an elapsed time s after its last discharge.In the linear setting, we extend an argument by Laurençot and Perthame to prove exponential decay to the steady state. This extension allows us to handle coefficients that have a large variation rather than constant coefficients. In another extension of the argument, we treat a weakly nonlinear case and prove total desynchronization in the network. For greater nonlinearities, we present a numerical study of the impact of the fragmentation term on the appearance of synchronization of neurons in the network using two "extreme" cases.Mathematics Subject Classification (2000)2010: 35B40, 35F20, 35R09, 92B20

Sublinear scalarizations for proper and approximate proper efficient points in nonconvex vector optimization

We show that under a separation property, a Q-minimal point in a normed space is the minimum of a given sublinear function. This fact provides sufficient conditions, via scalarization, for nine types of proper efficient points; establishing a characterization in the particular case of Benson proper efficient points. We also obtain necessary and sufficient conditions in terms of scalarization for approximate Benson and Henig proper efficient points. The separation property we handle is a variation of another known property and our scalarization results do not require convexity or boundedness assumptions.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Fernando García-Castaño and Miguel Ángel Melguizo-Padial acknowledge the financial support from the Spanish Ministry of Science, Innovation and Universities (MCIN/AEI) under grant PID2021-122126NB-C32, co-funded by the European Regional Development Fund (ERDF) under the slogan “A way of making Europe”

Integrating the common variability language with multilanguage annotations for web engineering

Web applications development involves managing a high diversity of files and resources like code, pages or style sheets, implemented in different languages. To deal with the automatic generation of custom-made configurations of web applications, industry usually adopts annotation-based approaches even though the majority of studies encourage the use of composition-based approaches to implement Software Product Lines. Recent work tries to combine both approaches to get the complementary benefits. However, technological companies are reticent to adopt new development paradigms such as feature-oriented programming or aspect-oriented programming. Moreover, it is extremely difficult, or even impossible, to apply these programming models to web applications, mainly because of their multilingual nature, since their development involves multiple types of source code (Java, Groovy, JavaScript), templates (HTML, Markdown, XML), style sheet files (CSS and its variants, such as SCSS), and other files (JSON, YML, shell scripts). We propose to use the Common Variability Language as a composition-based approach and integrate annotations to manage fine grained variability of a Software Product Line for web applications. In this paper, we (i) show that existing composition and annotation-based approaches, including some well-known combinations, are not appropriate to model and implement the variability of web applications; and (ii) present a combined approach that effectively integrates annotations into a composition-based approach for web applications. We implement our approach and show its applicability with an industrial real-world system.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

AdS/CFT Correspondence as a Consequence of Scale Invariance

We study an anisotropic scale transformation in the worldsheet description of D3-branes in Type IIB theory, and show that the transformation is really a symmetry in a region near D3-branes. AdS/CFT correspondence follows from this symmetry. We will explicitly show that Wilson loops in N=4 supersymmetric Yang-Mills theory and minimal surfaces in AdS_5 are related by the symmetry. The functional form of a supersymmetric Wilson loop operator is naturally derived from our worldsheet point of view.Comment: 20 pages, 8 figures, references adde