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In the present investigation, the feasibility of detecting the 1-chloro-1,2,2,2-tetrafluoroethane gas molecule on the outer surface of pristine single-walled boron nitride nanotube, as well as its aluminium- and gallium-doped structures, was carefully evaluated. For achieving this goal, a periodic boundary condition density functional theory level of study using both HSE06 and B3LYP-D3 functionals together with a 6-311G(d) basis set has been used. Subsequently, the CAM-B3LYP, xB97XD, and M06-2X functionals with a 6-311G(d) basis set were also employed to consider the single point energies. Natural bond orbital and quantum theory of atoms in molecules were implemented by using the HSE06/6-311G(d) method and the results were compatible with the electronic properties. In this regard, the total density of state, the Wiberg bond index, natural charge, natural electron configuration, donor-acceptor natural bond orbital interactions, and the second-order perturbation energies are performed to explore the nature of the intermolecular interactions. All of the energy calculations and population analyses show that by adsorbing of the gas molecule onto the surface of the considered nanostructures, the intermolecular interactions are of the type of strong chemical adsorption. Between the doped nanotubes, aluminium-doped nanotube has very high adsorption energy compared with gallium. Generally, it was revealed that the sensitivity of the adsorption will be increased when the gas molecule interacts with decorated nanotubes and decrease the HOMO-LUMO band gap; therefore, the change of electronic properties can be used to design suitable nanosensors. Key words: 1-chloro-1,2,2,2-tetrafluoroethane, HCFC-124, freon 124, boron nitride, density functional theory, natural bond orbital. Dans la presente etude, nous avons evalue en detail la faisabilite de la detection de la molecule gazeuse de 1chloro-1,2,2,2-tetrafluoroethane sur la surface externe d'un nanotube de nitrure de bore pur a simple paroi, ainsi que sur les structures analogues dopees a l'aluminium et au gallium. Pour ce faire, nous avons employe des conditions aux limites periodiques appliquees a la theorie de la fonctionnelle de la densite a un niveau theorique utilisant les fonctionnelles HSE06 et B3LYPD3 avec la base 6311G(d). Par la suite, nous avons egalement utilise les fonctionnelles CAMB3LYP, xB97XD et M062X avec la base 6311G(d) pour tenir compte des energies ponctuelles. Nous avons fait appel a la theorie de l'orbitale naturelle de liaison et a la theorie des atomes dans les molecules en utilisant la methode HSE06/6311G(d) et nous avons observe une concordance des resultats avec les proprietes electroniques. A cet egard, nous avons calcule la densite totale de l'etat, l'indice de liaison de Wiberg, la charge naturelle, la configuration electronique naturelle, les interactions donneur-accepteur des orbitales naturelles de liaison et les energies de perturbation de second ordre afin d'explorer la nature des interactions intermoleculaires. Tous les calculs d'energie et toutes les analyses de population indiquent que lorsque la molecule de gaz s'adsorbe sur la surface des nanostructures que nous avons etudiees, les interactions intermoleculaires sont du type d'adsorption chimique forte. Entre les nanotubes dopes, celui dope a aluminium presente une energie d'adsorption tres elevee par rapport a celui dope au gallium. De maniere generale, les resultats revelent que la sensibilite de l'adsorption sera accrue lorsque la molecule de gaz interagit avec des nanotubes decores et que l'ecart entre les bandes HOMOLUMO sera reduit. Par consequent, ce changement des proprietes electroniques peut etre mis a contribution pour concevoir des nanocapteurs fonctionnels. Mots-cles : 1-chloro-1,2,2,2-tetrafluoroethane, HCFC-124, freon 124, nitrure de bore, theorie de la fonctionnelle de la densite, orbitale naturelle de liaison., Introduction Nanotubes are structurally divided into carbon and non-carbon nanotubes. Carbon nanotubes (CNTs) were first discovered independently by Iijima and Ichihashi in 1991 in soot from carbon discharge in a [...]

In this study, we developed and explored a methodical image augmentation technique for swimmer localisation in northern German outdoor lake environments. When it comes to enhancing swimmer safety, a main issue we have to deal with is the lack of real-world training data of such outdoor environments. Natural lighting changes, dynamic water textures, and barely visible swimming persons are key issues to address. We account for these difficulties by adopting an effective background removal technique with available training data. This allows us to edit swimmers into natural environment backgrounds for use in subsequent image augmentation. We created 17 training datasets with real images, synthetic images, and a mixture of both to investigate different aspects and characteristics of the proposed approach. The datasets were used to train YOLO architectures for possible future applications in real-time detection. The trained frameworks were then tested and evaluated on outdoor environment imagery acquired using a safety drone to investigate and confirm their usefulness for outdoor swimmer localisation. [ABSTRACT FROM AUTHOR]

Experimental evidence shows that hydroxylated metal ions are often produced during cluster synthesis by atmospheric pressure spark ablation. In this work, we predict the ground state equilibrium structures of AgOkHm± clusters (k and m = 1–4), which are readily produced when spark ablating Ag, using the coupled cluster with singles and doubles (CCSD) method. The stabilization energy of these clusters is calculated with respect to the dissociation channel having the lowest energy, by accounting perturbative triples corrections to the CCSD method. The interatomic interactions in each of the systems have been investigated using the frontier molecular orbital (FMO), natural bond orbital (NBO) and quantum theory of atoms in molecules (QTAIM) methods. Many of the ground states of these ionic clusters are found to be stable, corroborating experimental observations. We find that clusters having singlet spin states are more stable in terms of dissociation than the clusters that have doublet or triplet spin states. Our calculations also indicate a strong affinity of the ionic and neutral Ag atom towards water and hydroxyl radicals or ions. Many 3-center, 4-electron (3c/4e) hyperbonds giving rise to more than one resonance structure are identified primarily for the anionic clusters. The QTAIM analysis shows that the O–H and O–Ag bonds in the clusters of both polarities are respectively covalent and ionic. The FMO analysis indicates that the anionic clusters are more reactive than the cationic ones. Using the cluster structures predicted by the CCSD method, we calculate the collision cross sections of the AgOkHm± family, with k and m ranging from 1 to 4, by the trajectory method. In turn, we predict the electrical mobilities of these clusters when suspended in helium at atmospheric pressure and compare them with experimental measurements. [ABSTRACT FROM AUTHOR]

Enterprises employ information systems to carry out their day-to-day business operations. Organizations implement business policies to enhance their competitive edge through efficient process management. This paper aims to propose a method that combines two approaches: evidencebased policymaking and process mining, to facilitate process reengineering. While numerous evidence-based approaches utilizing process mining techniques have been employed to assess process performance through measurements, these methods often focus on individual process instances. This is in contrast to Business Process Redesign (BPR) assessments, which encompass more comprehensive performance measurements, including overall process performance. This study proposes a method for analyzing process execution time, which includes Cycle time, Lead time, and Activity time. The aim is to support evidence-based policymaking in information systems through the use of process mining. Several key performance indicators (KPIs) have been defined for evidence-based management of business processes to identify process bottlenecks. The results of this paper demonstrate the application of process mining in analyzing the execution time of business processes. Using a real-world dataset, the study identified time-consuming activities and provided key performance indicators (KPIs) to guide process optimization. These findings demonstrate the effectiveness of process mining in identifying bottlenecks and inefficiencies within operational processes, ultimately leading to improved process performance and efficiency [ABSTRACT FROM AUTHOR]