Understanding Vine Hyperspectral Signature through Different Irrigation Plans: A First Step to Monitor Vineyard Water Status

The main challenge encountered by Mediterranean winegrowers is water management. Indeed, with climate change, drought events are becoming more intense each year, dragging the yield down. Moreover, the quality of the vineyards is affected and the level of alcohol increases. Remote sensing data are a potential solution to measure water status in vineyards. However, important questions are still open such as which spectral, spatial, and temporal scales are adapted to achieve the latter. This study aims at using hyperspectral measurements to investigate the spectral scale adapted to measure their water status. The final objective is to find out whether it would be possible to monitor the vine water status with the spectral bands available in multispectral satellites such as Sentinel-2. Four Mediterranean vine plots with three grape varieties and different water status management systems are considered for the analysis. Results show the main significant domains related to vine water status (Short Wave Infrared, Near Infrared, and Red-Edge) and the best vegetation indices that combine these domains. These results give some promising perspectives to monitor vine water status.

The Methodology of Assessing the Criminogenity of Administrative Territorial Units

The authors study the issues of applying mathematical methods to the assessment of the criminogenic levels in administrative-territorial units of the Republic of Kazakhstan. They have analyzed a considerable volume of statistical information for the past 20 years and, as a result, have identified the highest and the lowest number of registered crimes. Several indices were used to develop an index of criminogenity (ranging) of regions: crime level, graveness of crimes, size of population in a certain area. They recommend to define the public danger of crimes as a numerical value expressed in abstract units - points - based on the average sanctions, an average punishment imposed by a court and an average rating assigned by experts (researchers, practical specialists). The authors have studied modern Kazakh and foreign publications on the use of mathematical methods in criminology. The results of assessment according to three methods of ranging - legislative (legal), court, and expert - are presented in the tables. There is a correlation between legislative (legal) and court assessments. Calculations were used to determine the criminal status of some territorial units, which makes it possible to compare the number of crimes and the degree of their public danger for the population in the over-16 age group. In order to analyze the administrative-territorial units of the same type, the cities have been grouped according to the size of population. The presented methodology is reflected in the spectral scale on the «Map of Criminal Infringements» of the Committee for Legal Statistics and Special Records of the Prosecutor Generals Office for the Republic of Kazakhstan; it takes into account the distribution of cities into four groups which, in the end, will make it possible to obtain a maximally objective assessment of the criminal situation and to take preventive measures.

State 1st class working standard for units of wavelength in the range from 1.25 to 20.00 μm and wavenumber in the range from 500 to 8000 cm–1

The 1st class Working Standard for units of wavelength in the range from 1.25 to 20.0 μm and wavenumber in the range from 500 to 8000 cm–1 developed in VNIIOFI based on Fourier-Transform Infrared Spectrometer is presented. Dissemination of wavelength and wavenumber units to the 1st class Working Standard is carrying out from FTIR-spectrometer measurements of two peaks of lasers from the State primary special standard of units of signal propagation length and duration in the optical fiber of the average power, attenuation and wavelength for optical fiber communication systems and information transmission GET 170-2011. Spectral scale realization by the Working Standard is carrying by interferogram of internal He–Ne-laser during spectral intensity measurements of internal source. Dissemination for units of wavelength in the range from 1.25 to 20.00 μm and wavenumber in the range from 500 to 8000 cm–1 is provided by corresponding correction factor to measurement results. The developed accuracy chart that set traceability for wavelength and wavenumber measurement instruments to GET 170-2011 is presented.

Joint estimation of the Epoch of Reionization power spectrum and foregrounds

ABSTRACT The power spectrum of redshifted 21 cm emission brightness temperature fluctuations is a powerful probe of the Epoch of Reionization (EoR). However, bright foreground emission presents a significant impediment to its unbiased recovery from interferometric data. We estimate the power spectrum within a Bayesian framework and demonstrate that incorporating a priori knowledge of the spectral structure of foregrounds in the large spectral scale component of the data model enables significantly improved modelling of the foregrounds without increasing the model complexity. We explore two astrophysically motivated parametrizations of the large spectral scale model: (i) a constant plus power-law model of the form $q_{0}+q_{1}(\nu /\nu _{0})^{b_{1}}$ for two values of b1: b1 = 〈β〉GDSE and b1 = 〈β〉EGS, the mean spectral indices of the Galactic diffuse synchrotron emission and extragalactic source foreground emission, respectively; and (ii) a constant plus double power-law model of the form $q_{0}+q_{1}(\nu /\nu _{0})^{b_{1}}+q_{2}(\nu /\nu _{0})^{b_{2}}$ with b1 = 〈β〉GDSE and b2 = 〈β〉EGS. We estimate the EoR power spectrum from simulated interferometric data consisting of an EoR signal, Galactic diffuse synchrotron emission, extragalactic sources, and diffuse free–free emission from the Galaxy. We show that, by jointly estimating a model of the EoR signal with the constant plus double power-law parametrization of the large spectral scale model, unbiased estimates of the EoR power spectrum are recoverable on all spatial scales accessible in the data set, including on the large spatial scales that were found to be contaminated in earlier work.

Radiometric consistency assessment of hyperspectral infrared sounders

The radiometric and spectral consistency among the Atmospheric Infrared Sounder (AIRS), the Infrared Atmospheric Sounding Interferometer (IASI), and the Cross-track Infrared Sounder (CrIS) is fundamental for the creation of long-term infrared (IR) hyperspectral radiance benchmark data sets for both intercalibration and climate-related studies. In this study, the CrIS radiance measurements on Suomi National Polar-orbiting Partnership (SNPP) satellite are directly compared with IASI on MetOp-A and MetOp-B at the finest spectral scale and with AIRS on Aqua in 25 selected spectral regions through simultaneous nadir overpass (SNO) observations in 2013, to evaluate radiometric consistency of these four hyperspectral IR sounders. The spectra from different sounders are paired together through strict spatial and temporal collocation. The uniform scenes are selected by examining the collocated Visible Infrared Imaging Radiometer Suite (VIIRS) pixels. Their brightness temperature (BT) differences are then calculated by converting the spectra onto common spectral grids. The results indicate that CrIS agrees well with IASI on MetOp-A and IASI on MetOp-B at the long-wave IR (LWIR) and middle-wave IR (MWIR) bands with 0.1–0.2 K differences. There are no apparent scene-dependent patterns for BT differences between CrIS and IASI for individual spectral channels. CrIS and AIRS are compared at the 25 spectral regions for both polar and tropical SNOs. The combined global SNO data sets indicate that the CrIS–AIRS BT differences are less than or around 0.1 K among 21 of 25 spectral regions and they range from 0.15 to 0.21 K in the remaining four spectral regions. CrIS–AIRS BT differences in some comparison spectral regions show weak scene-dependent features.

Radiometric consistency assessment of hyperspectral infrared sounders

The radiometric and spectral consistency among the Atmospheric Infrared Sounder (AIRS), the Infrared Atmospheric Sounding Interferometer (IASI), and the Cross-track Infrared Sounder (CrIS) is fundamental for the creation of long-term infrared (IR) hyperspectral radiance benchmark datasets for both inter-calibration and climate-related studies. In this study, the CrIS radiance measurements on Suomi National Polar-orbiting Partnership (SNPP) satellite are directly compared with IASI on MetOp-A and -B at the finest spectral scale and with AIRS on Aqua in 25 selected spectral regions through one year of simultaneous nadir overpass (SNO) observations to evaluate radiometric consistency of these four hyperspectral IR sounders. The spectra from different sounders are paired together through strict spatial and temporal collocation. The uniform scenes are selected by examining the collocated Visible Infrared Imaging Radiometer Suite (VIIRS) pixels. Their brightness temperature (BT) differences are then calculated by converting the spectra onto common spectral grids. The results indicate that CrIS agrees well with IASI on MetOp-A and IASI on MetOp-B at the longwave IR (LWIR) and middle-wave IR (MWIR) bands with 0.1–0.2 K differences. There are no apparent scene-dependent patterns for BT differences between CrIS and IASI for individual spectral channels. CrIS and AIRS are compared at the 25 spectral regions for both Polar and Tropical SNOs. The combined global SNO datasets indicate that, the CrIS-AIRS BT differences are less than or around 0.1 K among 21 of 25 comparison spectral regions and they range from 0.15 to 0.21 K in the remaining 4 spectral regions. CrIS-AIRS BT differences in some comparison spectral regions show weak scene-dependent features.

The Spectral Scale of a Self-Adjoint Operator in a Semifinite von Neumann Algebra

We extend Akemann, Anderson, and Weaver'sSpectral Scaledefinition to include selfadjoint operators fromsemifinitevon Neumann algebras. New illustrations of spectral scales in both the finite and semifinite von Neumann settings are presented. A counterexample to a conjecture made by Akemann concerning normal operators and the geometry of the their perspective spectral scales (in the finite setting) is offered.

Extension of Spectral Scales to Unbounded Operators

We extend the notion of a spectral scale ton-tuples of unbounded operators affiliated with a finite von Neumann Algebra. We focus primarily on the single-variable case and show that many of the results from the bounded theory go through in the unbounded situation. We present the currently available material on the unbounded multivariable situation. Sufficient conditions for a set to be a spectral scale are established. The relationship between convergence of operators and the convergence of the corresponding spectral scales is investigated. We establish a connection between the Akemann et al. spectral scale (1999) and that of Petz (1985).