Single Set Of Measurements Research Articles

The Temporal and Spatial Dynamics of Succession in a Glacial Foreland in Southern Iceland: The Effects of Landscape Heterogeneity

One of the more visible consequences of anthropogenic climate change is the ongoing retreat of glaciers worldwide. Rates of primary succession in the resulting glacial forelands are commonly calculated from a single measurement set using a single set of measurements across a landscape of varying age, but repeated measurements over decadal scales may be a more effective means of examining the rates and trends of colonization and community development. Repeated measurements of vegetation groups in a glacial foreland in southern Iceland demonstrate that successional changes are measurable, as shown by the calculation of the dissimilarity index at sites over a 15 year interval. Inter-site dissimilarity validates the essential paradigm of primary succession, where vegetative coverage increases in the glacial foreland as a function of time and supports earlier interpretations saying that species richness decreases on older surfaces, even as the total vegetation cover increases. However, successional processes are subject to major abiotic factors, such as aspect, which is controlled by landscape topography, and the substrate composition. The glacial moraines and outwash plain are underlain by different substrates which produce separate successional trajectories. Succession on the moraines ultimately produces a birch-shrub-heath community, while the outwash deposits promote development of a moss-heath community.

An efficient estimator for source localization in WSNs using RSSD and TDOA measurements

Range-based localization has received considerable attention in wireless sensor networks due to its ability to efficiently locate the unknown source of a signal. However, the localization accuracy with a single set of measurements may be inadequate, especially in dynamic and noisy environments. To mitigate this problem, received signal strength difference (RSSD) and time difference of arrival (TDOA) measurements are used to develop an efficient estimator to reduce the bias and improve localization accuracy. First, the RSSD/TDOA-based maximum likelihood (ML) localization problem is transformed into a hybrid information nonnegative constrained least squares (HI-NCLS) framework. Then, this framework is used to develop an effective bias-reduction localization approach (BRLA) with a two-step linearization process. The first step employs a linear solving method (LSM) which exploits an active set method to obtain a sub-optimal estimator. The second step uses a bias reduction method (BRM) to mitigate the correlation from linearization and a weighted instrumental variables matrix (IVM) which is weakly correlated with the noise but strongly correlated with the data matrix (DM) is used in place of the DM. Performance results are presented which demonstrate that the proposed BRLA provides better localization performance than state-of-the-art methods in the literature.

Quantifying anisotropic thermal transport in two-dimensional perovskite (PEA2PbI4) through cross-sectional scanning thermal microscopy

In this paper, we investigated the anisotropic thermal transport in two-dimensional (2D) perovskite (phenethylammonium lead iodide) nanolayers through a measurement technique called cross-sectional scanning thermal microscopy. In this method, a target perovskite layer on a substrate was oblique polished with an Ar ion beam to create a low-angle wedge with nanoscale roughness that is followed by high-vacuum scanning thermal microscopy to obtain the thermal conductance map as a function of local thickness. The experimentally obtained data were processed with an analytical model and validated by the finite elemental analysis simulation to quantify the in-plane $({k}_{l,xy})$ and cross-plane thermal conductivities $({k}_{l,z})$ of the 2D perovskite from a single set of measurements with nanoscale resolution. We obtained ultralow thermal conductivity $({k}_{l}=0.25\ifmmode\pm\else\textpm\fi{}0.05\phantom{\rule{0.16em}{0ex}}\mathrm{W}\phantom{\rule{0.16em}{0ex}}{\mathrm{m}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}1})$ for the 2D perovskite along with an anisotropy $({k}_{l,\phantom{\rule{0.16em}{0ex}}xy}=0.45\ifmmode\pm\else\textpm\fi{}0.05\phantom{\rule{0.16em}{0ex}}\mathrm{W}\phantom{\rule{0.16em}{0ex}}{\mathrm{m}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}\mathrm{and}\phantom{\rule{0.16em}{0ex}}{k}_{l,\phantom{\rule{0.16em}{0ex}}z}=0.13\ifmmode\pm\else\textpm\fi{}0.05\phantom{\rule{0.16em}{0ex}}\mathrm{W}\phantom{\rule{0.16em}{0ex}}{\mathrm{m}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}1})$ linked to the unique structure of the perovskite and different phonon lifetimes and group velocities for in-plane and out-of-plane directions. The results that are available are essential for the thermal management of 2D perovskite-based optoelectronic devices and potential thermoelectric applications of these materials.

Statistical analysis of intensity fluctuations in the second harmonic of a multimode Nd:YAG laser through a modified Pearson correlation coefficient

We apply a recently proposed modified Pearson correlation coefficient to investigate the statistical properties of intensity fluctuations in the second harmonic as well as fundamental mode of a multimode $Q$-switched Nd:yttrium aluminum garnet laser. Above threshold the system displays a photonic ferromagneticlike spontaneous mode-locking phase with replica symmetry breaking (RSB). Differently from the photonic glassy phase in random lasers in which modes do not oscillate synchronously, in the present case a relevant fraction of modes oscillate coherently, but the synchronous oscillation of some modes is frustrated with the RSB arising from the fact that a given subset of modes is randomly activated at each excitation pulse with dominating coherent oscillation, frustrating the emergence of other modes. From a single set of measurements, the modified Pearson coefficient allows to identify that the onset of the RSB phenomenon between distinct spectra as the lasing threshold is crossed coincides with the emergence of correlations between different wavelengths in the same spectrum. As different subsets of longitudinal modes are nondeterministically activated after each shot, the RSB property indicates that distinct spectra can be either correlated or anticorrelated around both the fundamental mode and the second harmonic.

The study of the autochthonous population of the North of the Tobolsk Province in the works of A.A. Dunin-Gorkavich (based on the periodical press of Western Siberia at the beginning of the XX century)

The purpose of the article is to study and systematize previously unpublished materials of the newspapers of Western Siberia by A.A. Dunin–Gorkavich concerning the ethnography of the North of the Tobolsk province. The object of the article is the scientific heritage of A.A. Dunin-Gorkavich, dedicated to the composition, settlement, cultural and everyday features, material and spiritual culture of the indigenous population of the Tobolsk North at the beginning of the XX century. The relevance of the work lies in the choice of the source base – materials of the famous scientist and local historian A.A. Dunin-Gorkavich, published in local periodicals of Western Siberia. The basis of the work is the principle of historicism, integrity, objectivity, comprehensiveness. Both general scientific and traditional methods are used: systemic, historical-comparative, problem-historical, structural-functional. The fundamental work "Tobolsk North" is still one of the valuable sources for studying the life of the peoples of Siberia. Residents of Berezovsky and Surgut counties were at a low stage of cultural and economic development. To solve this problem, drastic changes proposed by A.A. Dunin-Gorkavich were required. For more mass circulation and readership, the scientist published many of his innovative ideas on the pages of the Siberian Leaflet, the Siberian Trade Newspaper and the Tobolsk Provincial Gazette. Publication in newspapers with the help of feedback (criticism, reviews, responses) allowed to build a constructive dialogue with progressive public figures, intellectuals, representatives of the bureaucracy. Such a return contributed to the development of a single set of measures and a partial solution to some of the difficulties of foreigners.

Experimental Validations of Reconstructed Excitation Forces Acting Inside a Solid Enclosure. Part I: Exterior Region

This paper presents the experimental validations of reconstructing the characteristics of the excitation forces that act inside a vibrating structure, which includes the location, type, amplitude, and spectrum, based on a single set of measurements of the normal surface velocity on the exterior surface by using the modified Helmholtz Equation Least Squares (HELS) method, as if one could see through this solid structure. Phase I of this paper shows the reconstruction of the vibroacoustic responses in the exterior region of the structure, including the field acoustic pressure, the surface acoustic pressure, the normal surface velocity or Operational Deflection Shape (ODS), the normal component of the time-averaged acoustic intensity, and the time-averaged acoustic power. Phase II of this paper illustrates the reconstruction of the excitation forces with the fluid-loading effects taken into consideration, based on the vibroacoustic responses reconstructed in the exterior region. The significance of the study, namely, the interrelationships among the excitation force, structural vibration, and acoustic radiation is discussed. The knowledge thus acquired may be important for engineers to analyze various complex noise and vibration issues in practice and to come up with the most cost-effective noise and vibration mitigation strategies.

Experimental Validations of Reconstructed Excitation Forces Acting Inside a Solid Enclosure. Part II: Interior Region

Part II of this paper discusses experimental validations of the reconstructed excitation forces acting inside a vibrating structure with the fluid-loading effect taken into consideration. Specifically, the characteristics of the excitation forces such as their locations, types, amplitudes, and spectra are reconstructed by using the modified Helmholtz Equation Least Squares (HELS) method, based on a single set of measurements of the normal surface velocity on the exterior surfaces, as if one could see through such a solid structure. Since the fluid-loading effect has a direct impact on the vibration responses of a structure, it is not possible to derive analytic solutions to vibration responses of the structure. Therefore, numerical solutions are sought by using the boundary element method (BEM). The fluid-loading effect, a.k.a., the reverberation sound field inside the structure is calculated based on the absorption coefficients and surface areas of the interior objects. The reconstructed excitation forces are then compared to the benchmark values and satisfactory agreements are obtained.

Open-source application for determination of proof strength based on the plastic extension method

Although the modern era brought forward the need for automatization of standard engineering routines, the process of determining proof stress is still mostly done manually. While norms dictate the testing procedure and relevant values, the data evaluation process is left for the user to define and is mostly not a documented part of the analysis. This paper presents an open-source application approach for evaluating tensile test data with the goal of determining the proof stress. The process itself is based on fitting an optimal line through experimental data points.The application requirements are:• Except for test specimen dimensions, no user input is required.• Usable for all materials where yielding occurs.• Will work on a single measurement set as well as multiple data sets.• Open source—addressing transparency and future development for other material testing methods.• Run with MATLAB and Octave.Until now, no numerical consensus existed on how to find the regions other than the procedure defined in EN ISO 6892-1, 2010, nor any heuristic that followed the norm.It is important to note that the application is made up of ten sections. Only three will be elaborated on in detail as they show the core solution.

Nurse Attitudes: A Descriptive Study of Families' Importance in Inpatient Nursing Care.

Family support and patient outcomes are linked to nurses' attitudes toward families' importance in patient care. The purpose of this study was to characterize inpatient oncology nurses' attitudes toward families' importance in nursing care and determine characteristics related to these attitudes. A descriptive, cross-sectional design was used with a single set of measurements from inpatient oncology nurses at a comprehensive cancer center in the southeastern United States. Nurse characteristics were summarized using frequency and percentages. Time variables were summarized using median and interquartile range. There were five primary outcomes. Nurses considered the role of the family important, but level varied by FINC-NA item. Characteristics related to family importance overall included hospital unit and general approach to care.

Robust self-testing of steerable quantum assemblages and its applications on device-independent quantum certification

Given a Bell inequality, if its maximal quantum violation can be achieved only by a single set of measurements for each party or a single quantum state, up to local unitaries, one refers to such a phenomenon as self-testing. For instance, the maximal quantum violation of the Clauser-Horne-Shimony-Holt inequality certifies that the underlying state contains the two-qubit maximally entangled state and the measurements of one party contains a pair of anti-commuting qubit observables. As a consequence, the other party automatically verifies the set of states remotely steered, namely the "assemblage", is in the eigenstates of a pair of anti-commuting observables. It is natural to ask if the quantum violation of the Bell inequality is not maximally achieved, or if one does not care about self-testing the state or measurements, are we capable of estimating how close the underlying assemblage is to the reference one? In this work, we provide a systematic device-independent estimation by proposing a framework called "robust self-testing of steerable quantum assemblages". In particular, we consider assemblages violating several paradigmatic Bell inequalities and obtain the robust self-testing statement for each scenario. Our result is device-independent (DI), i.e., no assumption is made on the shared state and the measurement devices involved. Our work thus not only paves a way for exploring the connection between the boundary of quantum set of correlations and steerable assemblages, but also provides a useful tool in the areas of DI quantum certification. As two explicit applications, we show 1) that it can be used for an alternative proof of the protocol of DI certification of all entangled two-qubit states proposed by Bowles et al., and 2) that it can be used to verify all non-entanglement-breaking qubit channels with fewer assumptions compared with the work of Rosset et al.

Box-cox-sparse-measures-based blind filtering: Understanding the difference between the maximum kurtosis deconvolution and the minimum entropy deconvolution

Blind filtering is an emerging topic in various domains to recover an excitation from responses measured by sensors. In the existing literature, the minimum entropy deconvolution is often regarded as the maximum kurtosis deconvolution without providing an underlying connection between them. However, a recent progress towards sparsity measures has shown that kurtosis is actually different from negative entropy. Moreover, a generalized sparse measure, called Box-Cox sparse measures (BCSM), has been proposed to establish a connection between the kurtosis and the negative entropy. Thus, this research investigates an underlying connection between the minimum entropy deconvolution and the maximum kurtosis deconvolution by using the BCSM. After that, the BCSM is incorporated into a generalized Rayleigh quotient to form a generalized blind filter that extracts a signal with the sparsest envelope spectrum. Finally, the effectiveness of the proposed generalized filter is verified using both simulated and real experimental bearing data. Results demonstrates that the proposed method can be used to detect multiple faults using a single measurement set.

ОСОБЛИВОСТІ ЗАСТОСУВАННЯ ТА ПОРІВНЯЛЬНА ХАРАКТЕРИСТИКА ОПЕРАЦІЙНИХ СИСТЕМ ОРГАНІЗАЦІЇ ВИРОБНИЦТВА

The article establishes and summarizes the application features, as well as provides a comparative description of the "traditional" production organization system and the "just in time" system. It is established that the "just in time" system, in fact, is a single set of measures that is carried out in order to achieve the maximum possible level of production with the use of minimum inventory of parts and components, semi-finished products and finished products, according to which the basic element of the system is to prevent any excess of raw materials, materials, equipment, etc. In order to ensure uninterrupted processes, the "just in time" system requires high quality products at every stage of the process, clear fulfillment of suppliers' contractual obligations and correct forecasting of demand for finished products. At the same time, special importance in the process of ensuring the continuity of flows and uninterrupted operation of equipment is attached to the creation of a system of scheduled preventive repairs. It is proved that the "just in time" supply system is a modern inventory management operating system, which has a number of significant advantages over the traditional approach. The article outlines the main obstacles to implementing and ensuring the effective application of the production organization system "just in time" by domestic enterprises. It is proved that the main condition for the full implementation and effective application of the operating system for organizing production "just in time" is to ensure flexible and as fast as possible restructuring of all enterprise processes. It is argued that the use of this system will allow achieving significant improvements by eliminating losses, preventing technological disruptions or failures, and eliminating warehouses of raw materials, materials, and finished products. At the same time, the implementation and further effective application of the "just in time" system will require strict and strict compliance with basic principles and approaches, provided that all employees of the enterprise are involved without exception.

Multi-Sensor Spatial Association Using Joint Range-Doppler Features

We investigate the problem of localizing multiple targets using a single set of measurements from a network of radar sensors. Such "single snapshot imaging" provides timely situational awareness, but can utilize neither platform motion, as in synthetic aperture radar, nor track targets across time, as in Kalman filtering and its variants. Associating measurements with targets becomes a fundamental bottleneck in this setting. In this paper, we present a computationally efficient method to extract 2D position and velocity of multiple targets using a linear array of FMCW radar sensors by identifying and exploiting inherent geometric features to drastically reduce the complexity of spatial association. The proposed framework is robust to detection anomalies, and achieves order of magnitude lower complexity compared to conventional methods. While our approach is compatible with conventional FFT-based range-Doppler processing, we show that more sophisticated techniques for range-Doppler estimation lead to reduced data association complexity as well as higher accuracy estimates of target positions and velocities.

МЕХАНИЗМ ОБЕСПЕЧЕНИЯ ЭКОНОМИЧЕСКОЙ БЕЗОПАСНОСТИ БИЗНЕСА САРАТОВСКОЙ ОБЛАСТИ В УСЛОВИЯХ КОРОНОКРИЗИСА: ПРОБЛЕМЫ И ПУТИ РЕШЕНИЯ

The purpose of the article is to consider the problems faced by regional business in the context of the coronavirus crisis. The main financial indicators of regional business are considered, which reflect the existing problems of entrepreneurship in the Saratov region. The volume of unprofitable organizations by various types of economic activity is presented, representing a tendency of decreasing business efficiency over the last year. The analysis of the indicator of the economic security of regional business is the indicator of the gross profit of business, which has a negative growth compared to the previous year. The main external and internal causes, as well as the problems of regional business in the context of a pandemic, are identified. Among the main problems, the authors highlight the high "Index of Administrative Pressure" on business, as well as "administrative barriers" that have a negative impact on the development and functioning of the business. The authors formulate the concept of "administrative barrier" as applied to the business of the Saratov region. As a result, the necessity of developing a single set of measures was substantiated, which would allow ensuring the economic security of business in the form of a “mechanism of economic security” for regional business. In order to select activities within the framework of ensuring the economic security of business, the authors determine the possible risk coefficient for regional business development in the current period. The calculation of the possible retrospective growth rate of its profitability is carried out in order to implement the necessary measures to improve it.

Frequency domain data merging in operational modal analysis based on least squares approach

Assembling of multi-setup measurements emerges as a challenging problem in the structural health monitoring applications and may cause some important issues in the estimation of global modal parameters such as frequency, damping ratio and modal shape vector. To overcome this problem, a novel frequency domain pre-identification data merging method is proposed in this study. In the proposed methodology, to obtain a single measurement set, a least squares approach is employed resulting in a global response that is scaled from the multi-setup data. For the verification of the proposed merging procedure, one numerical, two experimental studies and one real data application have been conducted. The results obtained from the numerical, experimental and real data analysis indicate that the presented methodology provides rather high-quality estimations for multi-setup measurement problems.

Simultaneous Spectral Estimation of Dephasing and Amplitude Noise on a Qubit Sensor via Optimally Band-Limited Control

The fragility of quantum systems makes them ideally suited for sensing applications at the nanoscale. However, interpreting the output signal of a qubit-based sensor is generally complicated by background clutter due to out-of-band spectral leakage, as well as ambiguity in signal origin when the sensor is operated with noisy hardware. We present a sensing protocol based on optimally band-limited "Slepian functions" that can overcome these challenges, by providing narrowband sensing of ambient dephasing noise, coupling additively to the sensor along the ${z}$-axis, while permitting isolation of the target noise spectrum from other contributions coupling along a different axis. This is achieved by introducing a finite-difference control modulation, which linearizes the sensor's response and affords tunable band-limited "windowing" in frequency. Building on these techniques, we experimentally demonstrate two spectral estimation capabilities using a trapped-ion qubit sensor. We first perform efficient experimental reconstruction of a "mixed" dephasing spectrum, composed of a broadband $1/f$-type spectrum with discrete spurs. We then demonstrate the simultaneous reconstruction of overlapping dephasing and control noise spectra from a single set of measurements, in a setting where the two noise sources contribute equally to the sensor's response. Our approach provides a direct means to augment quantum-sensor performance in the presence of both complex broadband noise environments and imperfect control signals, by optimally complying with realistic time-bandwidth constraints.

Measuring the transmission matrix of a scattering medium using epi-fluorescence light

There are several methods to focus light behind a scattering medium, but very few use fluorescence light as feedback and can be used without access to the distal side of the scatterer. Among all the wave-front shaping techniques, retrieving the transmission matrix of a scattering material is the only one that allows for focusing on multiple spots after a single set of measurements. Here we propose a method to retrieve the transmission matrix of a scatterer using fluorescence light as feedback without access to the distal side. The advantage of this method is that it allows focusing on the whole field of view after a single matrix measurement without access to the distal side of the sample, making it suitable for reflection epi-illumination geometry microscopy.

Multi-Task Learning for Multi-Dimensional Regression: Application to Luminescence Sensing

The classical approach to non-linear regression in physics is to take a mathematical model describing the functional dependence of the dependent variable from a set of independent variables, and then using non-linear fitting algorithms, extract the parameters used in the modeling. Particularly challenging are real systems, characterized by several additional influencing factors related to specific components, like electronics or optical parts. In such cases, to make the model reproduce the data, empirically determined terms are built in the models to compensate for the difficulty of modeling things that are, by construction, difficult to model. A new approach to solve this issue is to use neural networks, particularly feed-forward architectures with a sufficient number of hidden layers and an appropriate number of output neurons, each responsible for predicting the desired variables. Unfortunately, feed-forward neural networks (FFNNs) usually perform less efficiently when applied to multi-dimensional regression problems, that is when they are required to predict simultaneously multiple variables that depend from the input dataset in fundamentally different ways. To address this problem, we propose multi-task learning (MTL) architectures. These are characterized by multiple branches of task-specific layers, which have as input the output of a common set of layers. To demonstrate the power of this approach for multi-dimensional regression, the method is applied to luminescence sensing. Here, the MTL architecture allows predicting multiple parameters, the oxygen concentration and temperature, from a single set of measurements.

Clinical experience using Delta 4 phantom for pretreatment patient-specific quality assurance in modern radiotherapy

AbstractPurposeIn advanced radiotherapy techniques such as intensity-modulated radiation therapy (IMRT), the quality assurance (QA) process is essential. The aim of the study was to assure the treatment planning dose delivered during delivery of complex treatment plans. The QA standard is to perform patient-specific comparisons between planned doses and doses measured in a phantom.Materials and methodThe Delta 4 phantom (Scandidos, Uppsala, Sweden) has been used in this study. This device consists of diode matrices in two orthogonal planes inserted in a cylindrical acrylic phantom. Each diode is sampled per beam pulse so that the dose distribution can be evaluated on segment-by-segment, beam-by-beam, or as a composite plan from a single set of measurements. Ninety-five simple and complex radiotherapy treatment plans for different pathologies, planned using a treatment planning system (TPS) were delivered to the QA device. The planned and measured dose distributions were then compared and analysed. The gamma index was determined for different pathologies.ResultsThe evaluation was performed in terms of dose deviation, distance to agreement and gamma index passing rate. The measurements were in excellent agreement between with the calculated dose of the TPS and the QA device. Overall, good agreement was observed between measured and calculated doses in most cases with gamma values above 1 in >95% of measured points. Plan results for each test met the recommended dose goals.ConclusionThe delivery of IMRT and volumetric-modulated arc therapy (VMAT) plans was verified to correspond well with calculated dose distributions for different pathologies. We found the Delta 4 device is accurate and reproducible. Although Delta4 appears to be a straightforward device for measuring dose and allows measure in real-time dosimetry QA, it is a complex device and careful quality control is required before its use.

Reducing backaction when measuring temporal correlations in quantum systems

Dynamic correlations of quantum observables are challenging to measure due to measurement backaction incurred at early times. Recent work [P. Uhrich et al., Phys. Rev. A, 96:022127 (2017)] has shown that ancilla-based noninvasive measurements are able to reduce this backaction, allowing for dynamic correlations of single-site spin observables to be measured. We generalise this result to correlations of arbitrary spin observables and extend the measurement protocol to simultaneous noninvasive measurements which allow for real and imaginary parts of correlations to be extracted from a single set of measurements. We use positive operator-valued measures to analyse the dynamics generated by the ancilla-based measurements. Using this framework we prove that special observables exist for which measurement backaction is of no concern, so that dynamic correlations of these can be obtained without making use of ancillas.