High-accuracy source-independent radiometric calibration with low complexity for infrared photonic sensors

Radiometric calibration (RC) is an essential solution to guarantee measurements from infrared photonic sensors with certain accuracy, the main task of which is to determine the radiometric responsivity of sensor and usually be solved by comparing with some radiation source (i.e., blackbody), called source-based RC (SBRC). In addition to the complexity in manufacture, the nonideal characteristics of an available source will inevitably introduce unexpected uncertainties to reduce the final calibration accuracy by around 0.2–0.5 K in SBRC. Therefore, we propose an original source-independent RC (SIRC) principle based on modeling instead of comparing for SBRC, where the incident background radiation to detector, as a dominated factor influencing the responsivity characteristics of a photonic sensor, is modeled to implement RC for both two fundamental types (photoconductive and photovoltaic) of HgCdTe photonic detectors. The SIRC merely requires the temperature information of main components of a sensor other than some complex source and its assembly, and provides a traceable way at lower uncertainty costs relative to the traditional SBRC. The SIRC is being implemented in Fengyun-2 satellites since 2019, which ensures a long-term stable service of Chinese geostationary meteorological satellites for the global observation system under the framework of World Meteorological Organization. Moreover, a 20-year-period traceable Fengyun-2 dataset to be recalibrated with SIRC will benefit the further climate applications.

Frequency comb ptychoscopy

Multiheterodyne techniques using frequency combs—radiation sources whose lines are perfectly evenly-spaced—have revolutionized science. By beating sources with the many lines of a comb, their spectra are recovered. Even so, these approaches are fundamentally limited to probing coherent sources, such as lasers. They are unable to measure most spectra that occur in nature. Here we present frequency comb ptychoscopy, a technique that allows for the spectrum of any complex broadband source to be retrieved using a comb. In this approach, the spectrum is reconstructed by unfolding the simultaneous beating of a source with each comb line. We demonstrate this both theoretically and experimentally, at microwave frequencies. This approach can reconstruct the spectrum of nearly any complex source to high resolution, and the speed, resolution, and generality of this technique will allow chip-scale frequency combs to have an impact in a wide swath of new applications, such as remote sensing and passive spectral imaging.

Estimating Rupture Front of Large Earthquakes Using a Novel Multi-Array Back-Projection Method

A ruptured front obtained from high-frequency energy radiation is the key to understand the complex source. It is commonly observed that rupture fronts derived from different arrays often show some variations due to the obvious difference of the positioning accuracy of the far-field array between the azimuth and the epicentral distance. We developed a new multi-array back-projection method based on the classical back-projection method and applied the method to the 2015 MW7.8 Nepal earthquake. The back azimuth information with small error is separated from the classical back-projection results, and the azimuth intersection of multiple arrays is used to obtain more accurate spatial and temporal distribution information of the source rupture fronts.

Prunus cerasifera Ehrh. fruits are a source of biologically active substances and high-quality feedstock for Food for Specific Health Use

From the Southern Coast collection of Prunus cerasifera Ehrh. the fruits cultivars of the Nikitsky Gardens’ breeding Medovaya, Olenka, Rumyanaya Zorka and Idilliya were distinguished by their high taste qualities and the content of BAS. According to the norms of the Russian Federation, the fruits of these cultivars belong to the group of products with a high content of potassium and cuprum; satisfactory content of magnesium and ferrum, pastilles and jams from them belong to the group of products with a satisfactory content of potassium and cuprum. Cherry plum fruits, especially dark-colored ones, are a natural complex source of antioxidants, characterized by a high content of phenolic compounds and cuprum, and a satisfactory content of ascorbic acid and zinc. The content of pectin substances in the studied cultivars is comparable to that in apples. The fruits of the Idyllia cultivar with dark-colored pulp are distinguished by the maximum accumulation of pectins - 1.14%, ascorbic acid - 9.3, phenolic compounds – 441 mg/100 g, potassium – 11239, magnesium - 464, ferrum -10.81, zinc - 10.23, cuprum - 4.17, manganese - 0.228 mg/kg. Cherry plum fruits are characterized by a high content of BAS and are suitable for use in health nutrition both in fresh form and as raw materials for Food for Specific Health Use.

Can Instagram convince information to users?

In the age of social media, everyone can provide opinions via electronic word of mouth (eWOM). This experiment explores how users adopt culinary information on social media, especially Instagram, as one social media platform that has many users in Indonesia. With the many opinions that develop on social media, a phenomenon appears where users must sort out the information of choosing food products. The main objective of this study was to investigate the effect of source credibility and information quality on information adoption mediated attitudes towards information and information usefulness with the object of research on food products — analysis of the research model using partial least squares on 368 valid questionnaires distributed in East Java-Bali. The literature review and analytical techniques show that the source's credibility and the quality of information positively affect the adoption of information mediated attitudes towards information and the usefulness of the information. The novelty of research on the development of information adoption models is the complex source credibility variables, including expertise, trustworthiness, attractiveness, and homophily. It is an electronic persuasion that culinary business people need in the current era of social media. Keywords: E-wom, source credibility, information adoption, instagram, culinary.

Scattering and diffraction of a uniform complex-source beam by a slit in a perfectly conducting plane screen

A new multipole solution in plane-polar coordinates for the scattering of an arbitrary TE- or TM-polarized incident field by an infinitely extended slit in a plane screen is derived. To this end a classical three-domain problem with a complete multipole expansion in each of the domains is formulated. The unknown multipole amplitudes are found from the continuity conditions of the tangential electric and magnetic field components. Finally an infinite system of linear equations is derived which can be approximated by a numerically tractable finite one leading to a solution with an arbitrary accuracy. The results are numerically successfully compared to those ones obtained by classically solving the strip problem using Mathieu functions and by a subsequent application of the rigorous form of the Babinet principle. Numerical results include the comparison of the scattered fields obtained for an incident uniform complex-source beam and for an incident plane wave.