Kind Of Descriptor Research Articles

Computational design and screening of Single-Atom Phthalocyanine-Coordinated transition metal catalysts for the electrochemical cyanide reduction reaction

Catalysis facilitated by transition metals (TM), specifically when these are 4 N-coordinated and embedded within a phthalocyanine (Pc) framework, appears to have promising capabilities for the ecologically responsible generation of methane and ammonia, notably under conditions reflecting the ambient environment. The potential benefits of such applications have sparked escalating interest in studying single atom catalysts (SACs) with regard to their prospective role in the electrochemical cyanide reduction reaction (CNRR). Through the application of first-principles mechanistic investigations and electrochemical modeling, a variety of TM − Pc catalysts are examined under rigorous systematic exploration to ascertain their stability, activity and selectivity. To specifically address the scenarios, it's typically observed that the NC* model demands increased free energy inputs for CNRR, predominantly leading to the production of CH3NH2. In contrast, the analogous CN* model requires comparatively lower free energy, resulting in a more diversified mix of products, notably CH4 and NH3. Our research highlights the significant role of limiting potentials (UL) and their relationship with a particular kind of descriptor (φ) in crafting volcano plots, thereby elucidating the association between the inherent distinctive properties of various TM − Pc and their promising capabilities in CNRR activities. In a significant finding, the catalysts Sc − Pc, Ti − Pc, Cr − Pc and Fe − Pc are recognized as the most efficient electrocatalysts for CH4 and NH3 production through CNRR. This effectiveness is validated by their remarkable stability, superior reactivity, pronounced selectivity at relatively low limiting potentials (ranging from −0.05 to −0.39 V), and extraordinary Faradaic efficiencies exceeding 91.17 %.

A binary method of multisensor image registration based on angle traversal

Registration is a key step in image preprocessing. Absorbing the binary idea of BRIEF, we took all the feature points as a whole and generated a new binary descriptor that was irrelevant to the gray of the neighborhood of a feature point in the registration of visible light with infrared images. For each selected feature point, we constructed a circular area centered on it and divided the circumference equally as the sampling interval of the feature points. We then traversed all the intervals and built a binary code string as a descriptor for the feature point according to the relative position of the feature point. During the process of angle traversal, the Hamming distance was applied to identify the most similar descriptor pair. We then adopted an improved clustering algorithm to eliminate mismatched pairs. Experiments have demonstrated that this kind of descriptor has high accuracy and robustness for multisensor remote-sensing images. In particular, when dealing with the combination of visible and far-infrared images with local grayscale inversion, registration can also be accomplished well.

Image descriptor extraction using Android mobile devices for a video search system

The increasing amount of multimedia data makes it challenging to search for content, specially over an unlabeled database. Meanwhile, the proliferation of smartphones, which possess both video cameras and powerful processors, makes it possible to use these devices as part of a video search process. This paper presents a system for performing video searches using an Android mobile device, that records a video and extract one of three different kinds of global image descriptors, then it sends them to a server to perform a similarity search over a database. The precision of each kind of descriptor was measured. The efficiency of the system was compared with an analogous implementation which sends entire videos to the server and it was found to improve the system's response time and data usage.

Groundwater biodiversity and water quality of wells in the Southern region of Benin

This study performed in South-Eastern Benin aims to correlate the regional subterranean aquatic fauna, still poorly unknown, with the main physico-chemical characteristics of well-water used by human populations. Two kinds of descriptors are used. Physico-chemical analyses of water and faunistic sampling were consequently performed for one year at 15 stations. Multivariate analyses show different groups of stations depending on the kind of descriptor. Thus it appears that, in the Pobè region, the water quality, very variable from one station to another, is certainly not the main determinant of the well-water fauna distribution. Among the subterranean crustaceans, species belonging to genera Allocyclops and Metastenasellus have never been described before. These results are a contribution to the knowledge of the regional biodiversity and suggest that this biodiversity can be used as an indicator for better protection of regional groundwater. Cette étude, réalisée dans le Sud-Est du Bénin, a consisté à corréler la faune aquatique souterraine, encore inconnue au Bénin, avec la qualité physico-chimique de l’eau de puits utilisée par la population. Des analyses physicochimiques de l’eau et des prospections faunistiques ont été réalisées pendant un an sur 15 puits. Des analyses multivariées réalisées à partir de deux types de descripteurs ont permis de déterminer des groupes de stations qui diffèrent assez sensiblement. Il apparaît ainsi qu’à Pobè la qualité de l’eau, pourtant très variable, n’est certainement pas le seul facteur qui détermine la répartition de la faune stygobie. Parmi les Crustacés souterrains, des espèces des genres Allocyclops et Metastenasellus n’ont jusqu’ici jamais été observées. Ces résultats peuvent être utilisés à la fois pour mieux connaître la biodiversité régionale et pour justifier une protection des écosystèmes souterrains.