Anomalous Profiles Research Articles

Multi‐Concentric Generalized Perfect Vortex Beams by Hybrid Phase Metasurfaces

AbstractMetasurface‐based vortex beams are expected to overcome the current communication challenges of massive data and limited bandwidth by their theoretical infinite and mutually orthogonal states. However, limited by the spatial extension of array vortices, only finite orbital angular momentum (OAM) eigenstates are available, of which the expansion will boost the bandwidth toward an inexhaustible stage. In this manuscript, multi‐concentric generalized perfect vortex beams (G‐PVBs) are experimentally generated by the fabricated hybrid phase metasurfaces integrating generalized focusing phases and circular domain function into vortex phases. Diverse vortex shapes and helical lobes within beam patterns and spiral interferograms are both arranged in a non‐overlapping concentric manner instead of spatial arrays, respectively, breaking the limitation of symmetric shape while avoiding inter‐modal cross‐talk. The vortex shape, topological charge and vortex number are decoupled mutually in orthogonal polarization states, realizing both space and polarization multiplexing. Furthermore, shaped into anomalous profiles with asymmetric states of polarization, multi‐concentric vector G‐PVBs are experimentally generated to transmit parallelly stable order information with high robustness in turbulence environments. The proposed multi‐concentric G‐PVBs simultaneously expanded the novel vortex dimension by anomalous shapes and information channels of multi‐concentric OAM modes, providing potential application in high‐capacity vortex optical communication and information encryption.

Detection of coherent thermohaline structures over the global ocean using clustering

The classification of the ocean in water masses with similar physical and/or biogeochemical characteristics provides an ideal framework for an efficient monitoring of the change in ocean properties. Particularly, the combination of the seawater temperature and salinity set the stratification of the water column and impacts ocean circulation, with important implications for the surface-to-interior propagation of climate signals. The objective of this study is to find spatially coherent thermohaline structures in different regions of the global ocean, as well as their link with regional dynamics. To this end, we apply clustering techniques to identify water masses delimited by coherent thermohaline structures at different spatial scales over the global ocean. The clustering technique known as K-mean was used with a wide range of k values for conservative temperature and absolute salinity profiles of the entire ocean. Our analysis revealed the impact of the main dynamical oceanic structures (such as ocean fronts, currents, or regions of sluggish circulation) on the vertical thermohaline component. We present three cases of study, the California Current System, the Southern Ocean, and the Eastern Tropical Latitudes, where we could identify regions with common thermohaline characteristics (despite being from different ocean basins), as well as to identify seasonal changes and anomalous profiles. This method makes it possible to reduce the dimensionality of the water column, and allows for the establishment of regional limits driven by their vertical thermohaline structure instead of more rigid, and not always appropriate geographical borders. This has potential important applications for the monitoring and prediction of ocean variability in the context of a rapidly changing climate.

Classification of circular polarization Stokes profiles in a sunspot using k-means clustering

The magnetic and velocity fields in sunspots are highly structured on small spatial scales which are encoded in the Stokes profiles. The Stokes profiles are in turn, derived from a sequence of polarization modulations on the incoming light that are imaged using an analyser-detector combination. Our aim is to identify Stokes profiles in a sunspot which exhibit spectral characteristics that deviate from those associated with the Evershed flow and their corresponding spatial distribution. To that end, we employ the k-means clustering routine to classify Stokes V spectra in the penumbra of a regular, unipolar sunspot, that also comprises a granular and a filamentary light bridge. We find that 75% of the penumbral region, corresponding to about 93500 pixels, is dominated by profiles comprising two, nearly anti-symmetric lobes, while 21% of the area is occupied by three-lobed profiles that are associated with the Evershed flow returning to the solar photosphere. The remaining 4% of the penumbral area is dominated by four groups/families of profiles - Group 1: three-lobed profiles in which both the rest and strong downflowing (sometimes supersonic) component have the same polarity as the host sunspot and seen exclusively in the filamentary light bridge. Group 2: single, red-lobed profiles occupying an area of about 2% located at the outer penumbra in discrete patches that possibly signify the downflowing leg of an Ω-loop. Group 3: three-lobed or highly asymmetric profiles, in which the rest component and the strong downflowing component have an opposite polarity as the sunspot. These occupy about 1.4% of the penumbra’s area and are seen in conspicuous, elongated structures or isolated patches in the outer penumbra and at the penumbra-quiet Sun boundary. Group 4: three lobed-profiles, in which the rest component has the same polarity as the sunspot and a weaker, upflowing component with a polarity opposite that of the sunspot. These profiles are located close to the entrance of the filamentary light bridge and are found in only 0.12% of the penumbral area. These minority groups of profiles could be related to dynamic phenomena that could also affect the overlying chromosphere. The simplicity and speed of k-means can be utilized to identify such anomalous profiles in larger data sets to ascertain their temporal evolution and the physical processes responsible for these inhomogeneities.

Energy Consumption Auditing Anomaly Detection System of Robotic Manipulators based on a Generative Adversarial Network

Unexpected anomalies pose significant risks to the health and security of intelligent manufacturing systems. This paper proposes a generative adversarial network (GAN)-based anomaly detection framework specifically for monitoring robotic manipulator operation using a side-channel energy auditing mechanism. To tackle the limitation arising from the lack of labeled data, the GAN model is trained by a semi-supervised learning approach that identifies anomalies during online operations as outliers. The overfitting is purposely utilized during the model training to enlarge the difference between normal energy consumption patterns used for training and anomalous profiles in real-time testing. In addition, the GAN model is modified to use multiple discriminators to analyze the individual energy profile associated with each joint or motor. The anomaly is detected by evaluating the mean and standard deviation values of anomaly scores' distribution, and both values are continuously updated by Welford's algorithm in real time to take into account the effect of environmental variations during operations. The detection performance on our custom dataset demonstrates the feasibility of the proposed pipeline. Specifically, for physical attacks, the framework can achieve an accuracy of approximately 0.93 for instant-wise detection and 0.84 for event-wise detection.

The new abnormal: Identifying and ranking anomalies in the land trade market.

Large-scale national and transnational commercial land transactions, or Large-Scale Land Acquisitions (LSLAs), have been gaining a lot of academic attention since the late 2000s and since the reported rush for land, resulting in turn from an increase in demand for arable land. If many data exist to characterize land deals, the analysis of investment networks remain limited and predominantly portrays power asymmetries between countries from the Global North investing in the Global South. The aim of this work is to perform a deeper investigation on the land trade market, specifically focusing on cases that do not follow such narratives. For instance, almost 25% of the countries included in the transnational land trade network do not follow a strict investor/target dichotomy, thus being characterized by a double role, i.e., they both acquire and cede land in the transnational context. In order to globally acknowledge for what was currently considered as abnormal cases, we model open access data about LSLAs extracted from the Land Matrix Initiative (LMI) open-access database into a network graph, and adapt an eigenvector based centrality method originally conceived for online social networks, namely LurkerRank, to identify and rank anomalous profiles in the land trade market. We take into account three different network snapshots: a multi-sector network (including all the transnational deals in the LMI database), and three networks referring to specific investment sectors (agriculture,mines and biofuels). Experimental results show that emerging economies (e.g., China and Malaysia) play a central role in the land trade market, by creating alternative dynamics that escape the classic North/South one. Our analyses also show how African countries that are often seen as targets of land trade transactions in a specific sector, may often acquire foreign land in the context of investments in the same sector (i.e., Zimbabwe for biofuels and the Democratic Republic of Congo for the mining sector).

Borehole Magnetometry Test for Evaluating a Caisson’s Reinforced Depth: Experimental Results and Theoretical Modeling

Abstract The borehole magnetometry (BM) test was performed to evaluate the foundation reinforcement depth at a site where a telecommunication tower is supported by a single 2.3-m-diameter caisson foundation of known as-built design. An optical televiewer probe containing a three-axial fluxgate magnetometer was lowered into a vertical borehole 2.35 m distant from the center of the caisson and the profiles for the total magnetic field flux density, and its vertical component were acquired and used to generate, by subtracting the International Geomagnetic Reference Field background, the profiles for the total, BA, and vertical component, Bz,A, anomalous magnetic field. Four distinct graphical methods were used to evaluate the reinforced depth from the anomalous profiles and their first- and second-order derivatives. Two of the methods, including the one proposed in this study, based on locating the inflection points in the derivative profiles, evaluated the reinforced depth very close to the as-built depth (8.0 m). The reinforcement intensity of magnetization was then evaluated using the BA profile and a method based on the bipolar model. Theoretical modeling of BA and Bz,A and the derivative profiles was then performed using a three-dimensional prismatic model. By comparing modeled and experimental results, the induced magnetization was found to be an unsuited modeling assumption, with remanent magnetization being a better representation of the magnetic field around the caisson’s steel reinforcement, in agreement with the theory, given the high Koenigsberger ratio for steel. Also, the modeling revealed the need for a more complex representation of the magnetic sources, with added prisms to represent the effects of a magnetically-noisy environment and above-ground structures, as well as the presence of inhomogeneity and polarization changes along the reinforcement length.

Mathematical Description of the Enzymatic Activity of Proteins with Ionizable Groups Exhibiting Deviations from the Henderson-Hasselbalch Equation.

The ionization equilibrium implied in the calculation of the specific activity is classically described through the Henderson-Hasselbalch equation. An extension for the description of anomalous ionization profiles using the Hill equation is presented in this communication. The proposed framework was applied to the description of the specific enzymatic activity curve as a function of pH of five enzymes presenting different ionization states in their active site. The developed equation improves the description of relative enzymatic curves that deviate from the bell curve predicted by the application of the Henderson-Hasselbalch equation, regardless of the ionization scheme related to the active site.

1H R1\u03c1 relaxation dispersion experiments in aromatic side chains

Aromatic side chains are attractive probes of protein dynamic, since they are often key residues in enzyme active sites and protein binding sites. Dynamic processes on microsecond to millisecond timescales can be studied by relaxation dispersion experiments that attenuate conformational exchange contributions to the transverse relaxation rate by varying the refocusing frequency of applied radio-frequency fields implemented as either CPMG pulse trains or continuous spin-lock periods. Here we present an aromatic 1H R1ρ relaxation dispersion experiment enabling studies of two to three times faster exchange processes than achievable by existing experiments for aromatic side chains. We show that site-specific isotope labeling schemes generating isolated 1H–13C spin pairs with vicinal 2H–12C moieties are necessary to avoid anomalous relaxation dispersion profiles caused by Hartmann–Hahn matching due to the 3JHH couplings and limited chemical shift differences among 1H spins in phenylalanine, tyrosine and the six-ring moiety of tryptophan. This labeling pattern is sufficient in that remote protons do not cause additional complications. We validated the approach by measuring ring-flip kinetics in the small protein GB1. The determined rate constants, kflip, agree well with previous results from 13C R1ρ relaxation dispersion experiments, and yield 1H chemical shift differences between the two sides of the ring in good agreement with values measured under slow-exchange conditions. The aromatic1H R1ρ relaxation dispersion experiment in combination with the site-selective 1H–13C/2H–12C labeling scheme enable measurement of exchange rates up to kex = 2kflip = 80,000 s–1, and serve as a useful complement to previously developed 13C-based methods.

A data analytics-based tool for the detection and diagnosis of anomalous daily energy patterns in buildings

In this paper, a tool for the detection and diagnosis of anomalous electrical daily energy patterns relative to a transformer substation of a university campus was developed and tested. Through an innovative pattern recognition analysis consisting in a multi-step clustering process, six clusters of anomalous daily load profiles were identified and isolated in two-year historical data of total electrical energy consumption. The infrequent electrical load profiles were found to be strongly affected, in terms of both shape and magnitude, by the energy consumption behaviour related to the heating/cooling mechanical room. Then, a fault-free predictive model, which uses artificial neural network (ANN) in combination with a Regression Tree, was developed to detect anomalous trends of the electrical energy consumption. The model was able to detect the 93.7% of the anomalous profiles and only the 5% of fault-free days were wrongly predicted as anomalous. Eventually, a diagnosis phase was conceived and validated with a testing data set. A number of daily abnormal load profiles were detected and compared with the centroids of the anomalous clusters identified in the pattern-recognition stage. The work led to the development of a flexible intelligent tool useful for operating a continuous commissioning of the campus facilities.

Anomalous Fano Resonance in Double Quantum Dot System Coupled to Superconductor

We analyze the influence of a local pairing on the quantum interference in nanoscopic systems. As a model system we choose the double quantum dot coupled to one metallic and one superconducting electrode in the T-shape geometry. The analysis is particularly valuable for systems containing coupled objects with considerably different broadening of energy levels. In such systems, the scattering of itinerant electrons on a discrete (or narrow) energy level gives rise to the Fano-type interference. Systems with induced superconducting order, along well understood Fano resonances, exhibit also another features on the opposite side of the Fermi level. The lineshape of these resonances differs significantly from their reflection on the opposite side of the Fermi level, and their origin was not fully understood. Here, considering the spin-polarized tunneling model, we explain a microscopic mechanism of a formation of these resonances and discuss the nature of their uncommon lineshapes. We show that the anomalous Fano profiles originate solely from the pairing of nonscattered electrons with scattered ones. We investigate also the interplay of each type of resonances with the Kondo physics and discuss the resonant features in differential conductivity.

Mass‐dependent parameters of extensive air showers with anomalous longitudinal profiles

We investigate possibilities to determine the mass of a primary particle from anomalous longitudinal profiles of extensive air showers. Such profiles are predicted utilizing a Monte Carlo technique together with the contemporary high‐energy interaction models. The depth of shower maximum, which is commonly used for the mass composition analyses, is inspected and its performance to discriminate between primary species is studied. We search for alternative observables that have better properties in the case of anomalous profiles.

Expanded Croatian 12 X-STR loci database with an overview of anomalous profiles

In order to implement X-chromosome short tandem repeat (X-STR) typing into routine forensic practice, reference database of a given population should be established. Therefore we extended already published data with additional 397 blood samples from unrelated Croatian citizens, and analyzed the total of 995 samples (549 male and 446 female) typed by Investigator® Argus X-12 Kit. To test genetic homogeneity of consecutively processed five historic-cultural regions covering the entire national territory, we calculated pairwise Fst genetic distances between regions based on allele and full haplotype frequencies. Since the comparison did not yield any statistically significant difference, we integrated STR profile information from all regions and used the whole data set to calculate forensic parameters. The most informative marker is DXS10135 (polymorphism information content (PIC = 0.929) and the most informative linkage group (LG) is LG1 (PIC = 0.996). We confirmed linkage disequilibrium (LD) for seven marker pairs belonging to LG2, LG3 and LG4. By including LD information, we calculated cumulative power of discrimination that amounted to 0.999999999997 in females and 0.999999005 in males. We also compared Croatia with 13 European populations based on haplotype frequencies and detected no statistically significant Fst values after Bonferroni correction in any LG. Multi-dimensional scaling plot revealed tight grouping of four Croatian regions amongst populations of southern, central and northern Europe, with the exception of northern Croatia. In this study we gave the first extensive overview of aberrant profiles encountered during Investigator® Argus X-12 typing. We found ten profiles consistent with single locus duplication followed by tetranucleotide tract length polymorphism. Locus DXS10079 is by far the most frequently affected one, presumably mutated in eight samples. We also found four profiles consistent with X-chromosome aneuploidy (three profiles with XXX pattern and one profile with XXY pattern). In conclusion, we established integral forensic Croatian X-chromosome database, proved forensic pertinence of Investigator® Argus X-12 Kit for the entire Croatian population and identified locus DXS10079 as a potential duplication hotspot.

Energy of the Sea Craft Contour — Anomalous Wave System

The article is devoted to a numerical study of the contour - anomalous wave system and the quantitative estimates of its energy parameters. The author discovered that the profile of an anomalous wave undergoes the following stages: the initial profile, the profile with the first maximum height, the two-humped profile, the profile with a second maximum height, and the breaking profile. The problem is solved by CFD method in three stages. At the beginning the density maximum of the kinetic energy and its position on the anomalous wave profiles was calculated. It was discovered that the anomalous wave profile with the second maximum has the highest energy density and presents the greatest danger to the contour stability. Then, the numerical studies demonstrated that the kinetic energy increased as we approached the time of the anomalous wave collapse. It was discovered that the sum of the kinetic and potential energies is reduced due to the dissipation associated with the physical and turbulent viscosity. Eventually, we calculated the contour capsizing work. It was revealed that the anomalous wave energy loss corresponded to the contour capsizing work and increased with the vessel displacement. The relative value limit of the anomalous wave energy losses on bad moving contour reached 40 %. The received results can be used, firstly, for development of CFD based numerical studies. Secondly, the results can be used as the database for improvement of the design of the vessels, and also as a motive to search for causes of shipwrecks of vessels over 27000 tons, which did not capsize due to anomalous wave.

Searching for Anomalous Longitudinal Profiles with the FRAM Telescope

The study of anomalous longitudinal profiles of extensive air showers presents an interesting opportunity to gain additional insight about the character of hadronic interactions at the highest energies. Moreover, the presence of such profiles would represent direct evidence of a light component in the primary cosmic rays of a given energy, independently of hadronic interaction models. The ratio of profiles observed to have a “double bump” structure (with two clearly distinguishable atmospheric depths of maximum particle count) compared to the total number of events can moreover be used to test the predictions of interaction models. However, the majority of such profiles observed at the Pierre Auger Observatory are caused by clouds. Here we describe a method of rapid monitoring of particularly interesting cosmic ray events, using the F/Photometric Rapid Atmospheric Monitor (FRAM) telescope to identify events with clear, cloudless atmospheric background. The function of FRAM is described in detail and the number of triggered events is presented.

Multicomponent diffusion in aluminosilicate garnet: coupling effects due to charge compensation

ABSTRACTThree kinds of multicomponent diffusion effects, arising from three distinct physical mechanisms, are evident in stranded diffusion profiles at the rims of partially resorbed garnets from the contact aureole of the Makhavinekh Lake Pluton, northern Labrador. Profiles that display a subtle maximum in Ca concentration are explained by the prevailing ideal mean-field theory of multicomponent diffusion, but models implementing that theory cannot replicate inverted profiles for Li and internal maxima for Nd, Sm, and Eu. The anomalous profiles are quantitatively reproduced, however, by numerical simulations employing a model based on coupled movement of charge-compensating groups during diffusional transport of yttrium and the rare-earth elements (Y+REEs). An alkali-type charge-compensation mechanism for the heterovalent substitution of Y+REEs on dodecahedral sites in garnet produces direct charge coupling between Li+ and (Y+REE)3+ and leads to co-diffusion of Li+-(Y+REE)3+ pairs, with the result that Li profiles closely mimic those for Y+REEs. A menzerite-type charge-compensation mechanism produces indirect charge coupling among all Y+REE components, with the result that the fluxes of low-abundance REEs become partly dependent on the fluxes of Y+REEs present in higher abundance. These findings have implications for the robustness of Li profiles in garnet as monitors of fluid–rock interaction, for geochronology based on the Sm–Nd and Lu–Hf systems, and for future experimental attempts to quantify rates of diffusion in garnet.

5. Psychophysiological responsivity and conscious appraisal of affective stimuli in non-organic syncope

Transient losses of consciousness and muscular tone that characterize syncope are due to a sudden decrease of blood flow to the brain. Nevertheless, in part of patients reporting syncope episodes, the classic diagnostic process does not lead to a proper organic etiology – e.g. neutrally mediated or cardiac. Psychological non-organic factors like emotional dysregulation or anxiety mechanisms might act as triggers for those clinical manifestations. Given the link between affective experience and sympathetic-parasympathetic autonomic system, this research aims at investigating the hypothesis of a psychogenic etiopathogenesis and at sketching a clearer picture of affective responses in syncope. Control (healthy volunteers) and clinical (syncope patients with no organic etiology) groups were presented with arousing affective visual stimuli and assessed by psychometric tests. In order to explore both automatic and conscious processing of affective information, we recorded participants’ psychophysiological responses (autonomic and EEG) and subjective appraisal ratings (valence and arousal). The comparison of psychometric, electrophysiological and autonomic data across patients and control subjects showed anomalous response profiles, with partially incongruent autonomic automatic psychophysiological responses and conscious appraisal ratings. While the dysregulation of psychophysiological responsivity might characterize syncope profiles, the complexity of clinical pictures suggest that different non-organic syncope subtypes may exist.

MULTI-WAVELENGTH STUDY OF A DELTA-SPOT. I. A REGION OF VERY STRONG, HORIZONTAL MAGNETIC FIELD

ABSTRACT Active region NOAA 11035 appeared in 2009 December, early in the new solar activity cycle. This region achieved a delta sunspot (δ spot) configuration when parasitic flux emerged near the rotationally leading magnetic polarity and traveled through the penumbra of the largest sunspot in the group. Both visible and infrared imaging spectropolarimetry of the magnetically sensitive Fe i line pairs at 6302 and 15650 Å show large Zeeman splitting in the penumbra between the parasitic umbra and the main sunspot umbra. The polarized Stokes spectra in the strongest field region display anomalous profiles, and strong blueshifts are seen in an adjacent region. Analysis of the profiles is carried out using a Milne–Eddington inversion code capable of fitting either a single magnetic component with stray light or two independent magnetic components to verify the field strength. The inversion results show that the anomalous profiles cannot be produced by the combination of two profiles with moderate magnetic fields. The largest field strengths are 3500–3800 G in close proximity to blueshifts as strong as 3.8 km s−1. The strong, nearly horizontal magnetic field seen near the polarity inversion line in this region is difficult to understand in the context of a standard model of sunspot magnetohydrostatic equilibrium.

Spatio-temporal variability of CO and O3 in Hyderabad (17°N, 78°E), central India, based on MOZAIC and TES observations and WRF-Chem and MOZART-4 models

This article is based on the study of the seasonal and interannual variability of carbon monoxide (CO) and ozone (O3) at different altitudes of the troposphere over Hyderabad, India, during 2006–2010 using Measurement of OZone and water vapour by Airbus In-Service Aircraft (MOZAIC) and observation from Tropospheric Emission Spectrometer (TES) aboard NASA's Aura satellite. The MOZAIC observations show maximum seasonal variability in both CO and O3 during winter and pre-monsoon season, with CO in the range (100–200)±13 ppbv and O3 in the range (50–70)±9 ppbv. The time-series of MOZAIC data shows a significant increase of 4.2±1.3 % in the surface CO and 6.7±1.3 % in the surface O3 during 2006–2010 in Hyderabad. From MOZAIC observations, we identify CO and O3 profiles that are anomalous with respect to the monthly mean and compare those with Weather Research Forecast model coupled with Chemistry (WRF-Chem) and Model for OZone and Related Tracers, version 4 profiles for the same day. The anomalous profiles of WRF-Chem are simulated using three convection schemes. The goodness of comparison depends on the convection scheme and the altitude region of the troposphere.

HIERARCHICAL CLUSTERING ALGORITHM FOR DETECTING ANOMALOUS PROFILES IN COMPUTER SYSTEMS

We introduce a new intrusion detection method based on the Hierarchical Clustering Algorithm (HCA), to detect anomalous user’s profiles. In the Unix system, a simple user has only some privileges (can access to some resources), but the root user has more privileges. So, we can speak here about hierarchy of users. By the same way, we can use a hierarchy of users in intrusion detection field, to distinguish between the normal user and suspicious user. Many data mining methods were already used in previous works in intrusion detection. Even if some of them led to interesting results, but they still suffer from some weaknesses. This is the reason why we focused in this study on the use of the HCA to detect anomalous profiles. A survey of intrusion detection methods is presented. The HCA procedure is described in detail. Our simulation results demonstrate the robustness of our approach in comparison to some previous used methods.

Determination of the lifetime of molecules O 2 + and estimation of the flux of penetrating electrons generating a cloud of excess concentration of O 2 + in the ionosphere at altitudes above 220 km

The occurrence of anomalous (nonthermal) profiles of green emission of oxygen atoms detected with a Fabry-Perot spectrometer in auroras with the effect of a rapid decrease in the intensity of the wings of their dissociative component has been investigated. Based on an analysis of these measured profiles, it has been found that the characteristic time of recombination of a molecular oxygen ion at altitudes of 200–400 km is about 5–7 s. It appears that these molecular ions occur in a horizontally limited region of the auroral ionosphere as a result of ionization by a space localized flux of soft electrons with energies of 0.2–0.4 keV penetrating up to altitudes of 200 km. The estimation of the electron flux produces a value of 1010–1013 electrons cm−2 s−1. They generate the excess concentration n(O2+ ) ~ 5.6 × 105 cm−3.