Surface-enhanced mid-infrared absorption spectroscopy using miniaturized-disc metasurface

Surface-enhanced infrared spectroscopy is an important technique for improving the signal-to-noise ratio of spectroscopic material identification measurements in the mid-infrared fingerprinting region. However, the lower bound of the fingerprinting region receives much less attention due to a scarcity of transparent materials, more expensive sources, and weaker plasmonic effects. In this paper, we present a miniaturized metasurface unit cell for surface-enhanced infrared spectroscopy of the 15-$$\upmu$$ μ m vibrational band of CO$$_{2}$$ 2 . The unit cell consists of a gold disc, patterned along the edge with fine gaps/wires to create a resonant metamaterial liner. In simulation, our plasmonic metamaterial-lined disc achieves greater than $$4\times$$ 4 × the average field intensity enhancement of a comparable dipole array and a miniaturized size of $$\lambda _0/5$$ λ 0 / 5 using complex, 100-nm features that are patterned using 100-kV electron-beam lithography. In a simple experiment, the metamaterial-lined disc metasurface shows a high tolerance to fabrication imperfections and enhances the absorption of CO$$_{2}$$ 2 at 15 $$\upmu$$ μ m. The resonant wavelength and reflection magnitude can be tuned over a wide range by adjusting the liner feature sizes and the metasurface array pitch to target other vibrational bands. This work is a step toward low-cost, more compact on-chip integrated gas sensors.

A method for exploring attitude systems by combining Belief Network Analysis and Item Response Theory (ResIN)

Belief network analysis (BNA) is a new class of methods with strong potential to research the organization and development of abstract meaning systems. By mapping the attitude system, this method provides a more profound understanding of often “fuzzy” concepts such as ideologies, worldviews, and norm systems. BNA therefore holds potential implications for a plethora of socially relevant issues. For example, by informing the architecture of extreme belief sets or lines of conflict underlying partisan polarization. Despite the huge potential of this approach, it has some major limitations. Indeed, BNA methods start from the simplistic assumption that opposing groups should be perfectly symmetric in their attitudes (e.g. the more democrats are positive, the more republicans should be negative about each topic). Another important aspect of BNA methods is that they are often grounded on new, instead of well-established theories. This sometimes results in problems of interpretation and reliability of the results.In this article, we introduce a new method by combining BNA with item response theory (IRT). We refer to it as the Response-Item Network (or ResIN) method. This method has the advantage of being grounded in the well-developed psychometrics literature. Furthermore, it allows us to analyze attitudes from different groups without assuming symmetric behavior. This allows us to explore more deeply relationships and differences in the attitude system.Besides validating ResIN using IRT, we also test this method on real data, showing that it produces new insights compared to both classical BNA and IRT. Indeed, we are able to easily distinguish attitudes which belong to the republican and to the democrat side, even in counter-intuitive situations. We furthermore validated the reliability of these results by relying on additional data, such as self-identification measurements.

Analysis of the Surface Condition and Changes in Crystallographic Structure of Zirconium Oxide Affected by Mechanical Processing

Zirconium oxide is a material commonly used in dental prosthetics for making cups of permanent prosthetic restorations. In order to properly prepare the surface of zirconium oxide for prosthetic treatment, it must be veneered with ceramics. The quality of cup-veneered ceramics is dependent on many factors, including the surface free energy (SFE) and transformation of zirconium oxide. The aim of the study was to investigate the type of phase transition and the value of free energy of the surface subjected to machining (wet and dry grinding, polishing). Quantitative and qualitative phase identification measurements showed that mechanical treatment causes transformation of the tetragonal phase into a monoclinic phase in the zirconium oxide surface. Prepared samples were analyzed by means of X-ray diffraction (XRD), which confirmed the phenomenon of transition. Measurements of the wetting angle and the calculated values of the surface free energy (SFE) showed no significant differences between the samples subjected to each treatment

Identification method for assessing the state vibration strength of the aircraft engine

A method foraircraft engine state assessment is described, based on the theory of identification measurements and consisting in the analysis of the regularity properties of the temporal and correlation functions of the vibration signal. An example of an aircraft engine dynamics analysis during flight tests is considered. Four classes of states are distinguished according to the “norm – defect” scale.

Webcam Based Computerized Attendance System using Face Recognition Algorithms

An automated executive participation process, which relies on face recognition and identification measurements, identifies the understudy as it joins the classes and marks the participation by marking it Particular on going circumstances are considered for evaluating the performance of various face recognition systems. This paper provides other than the methods to be used to deal with hazards such as caricature. At the moment, which stands out from traditional engagement, this programs spares time and also Monitor the students

Recorded captures of American lobster (Homarus americanus) in Swedish waters and an observation of predation on the European lobster (Homarus gammarus)

The intentional or unintentional release of American lobsters (Homarus americanus), imported through the European seafood trade, has resulted in findings of H. americanus in European waters. A total of 36 specimens was recorded within a smaller area, halfway along the Swedish west coast, between 2008 and 2016. The lobsters were caught by both recreational and professional fishermen and delivered to the Institute of Marine Research in Lysekil, where species identification, measurements, and genetic sampling were performed. Twenty-five of these lobsters were caught inside the sill of the Gullmar Fjord, most of them close to Lysekil harbor, where escapes from an illegal holding is suspected. Six females had eggs, which in two cases were hybrids. While there is no evidence to suggest that a population has been established in the Gullmar Fjord or elsewhere in Swedish waters, serious concerns must be raised regarding the possible consequences for the native species. An American lobster has for the first time been filmed eating a killed European lobster (Homarus gammarus) in Swedish waters.