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Aiming to solve the problems with easy false detection of small targets in river floating object detection and deploying an overly large model, a new method is proposed based on improved YOLOv5s. A new data augmentation method for small objects is designed to enrich the dataset and improve the model's robustness. Distinct feature extraction network levels incorporate different coordinate attention mechanism pooling methods to enhance the effective feature information extraction of small targets and improve small target detection accuracy. Then, a shallow feature map with 4-fold down-sampling is added, and feature fusion is performed using the Feature Pyramid Network. At the same time, bilinear interpolation replaces the up-sampling method to retain feature information and enhance the network's ability to sense small targets. Network complex algorithms are optimized to better adapt to embedded platforms. Finally, the model is channel pruned to solve the problem of difficult deployment. The experimental results show that this method has a better feature extraction capability as well as a higher detection accuracy. Compared with the original YOLOv5 algorithm, the accuracy is improved by 15.7%, the error detection rate is reduced by 83% in small target task detection, the detection accuracy can reach 92.01% in edge testing, and the inference speed can reach 33 frames per second, which can meet the real-time requirements. [ABSTRACT FROM AUTHOR]

This paper considers the nonfragile observer-based guaranteed cost finite-time control of discrete-time positive impulsive switched systems(DPISS). Firstly, the positive observer and nonfragile positive observer are designed to estimate the actual state of the underlying systems, respectively. Secondly, by using the average dwell time(ADT) approach and multiple linear co-positive Lyapunov function (MLCLF), two guaranteed cost finite-time controller are designed and sufficient conditions are obtained to guarantee the corresponding closed-loop systems are guaranteed cost finite-time stability(GCFTS). Such conditions can be solved by linear programming. Finally, a numerical example is provided to show the effectiveness of the proposed method.

This paper considers the guaranteed cost finite-time boundedness of positive switched nonlinear systems with D-perturbation and time-varying delay. Firstly, the definition of guaranteed cost finite-time boundedness is introduced. By using the Lyapunov-Krasovskii functional and average dwell time (ADT) approach, an output feedback controller is designed and sufficient conditions are obtained to ensure the corresponding closed-loop systems to be guaranteed cost finite-time boundedness (GCFTB). Such conditions can be solved by linear programming. Finally, two examples are provided to show the effectiveness of the proposed method.

The performance of various density functional theories (B3LYP, B3PW91, B3P86, B1LYP, BMK, MPWB1K, PBE0, and MPWB95) was examined for calculating N-NO2 bond dissociation energies (BDEs) of 10 N-nitroacylamide compounds. The CBS-4M method was also used. By comparing the calculated results with the experimental values, it was observed that B1LYP/6-31[G.sup.**] and B3LYP/6-31+[G.sup.**] provided accurate BDEs. Especially, B3LYP/6-31+[G.sup.**] was recommended because of its smaller maximum absolute deviation. Further, substituent effects based on the B3LYP/6-31+[G.sup.**] method were analyzed. The result shows that an electron-donating group increases the BDE of the parent [C.sub.6][H.sub.5]-CON(C[H.sub.3]) N[O.sub.2], while an electron-withdrawing group decreases the BDE of the parent [C.sub.6][H.sub.5]-CON (C[H.sub.3])N[O.sub.2]. Subsequently, the BDEs of the other N-nitroacylamindes were estimated. Key words: density functional theory, polarized continuum model, N-nitroacylamides compounds, bond dissociation energy, substituent effects. On a examine les performances relatives de diverses variantes de la theorie de la fonctionnelle de la densite (B3LYP, B3PW91, B3P86, B1LYP, BMK, MPWB1K, PBE0 et MPWB95) pour calculer les energies de dissociation de la liaison (EDL) N-N[O.sub.2] de composes de la famille de 10 N-nitroacylamides. On a aussi fait appel a la methode CBS-4M. Une comparaison des resultats des calculs avec les resultats experimentaux a permis d'observer que les methodes B1LYP/631[G.sup.**] et B3LYP/6-31+[G.sup.**] conduisent aux energies de dissociation de liaison les plus exactes. On recommande particulierement la methode B3LYP/6-31+[G.sup.**] en raison du fait que sa deviation absolue est la plus faible. On a de plus analyse l'effet de substituant par la methode B3LYP/6-31+[G.sup.**]. Les resultats montrent qu'un groupe electrodonneur augmente l'energie de dissociation de la liaison du compose fondamental, [C.sub.6][H.sub.5]-CON(C[H.sub.3])N[O.sub.2], alors qu'un groupe electroattracteur la diminue. Finalement, on a aussi evalue les energies de dissociation de liaison d'autres N-nitroacylamides. Mots-cles : theorie de la fonctionnelle de la densite, modele du continuum polarise, composes de la famille des N-nitroacylamides, energie de dissociation de la liaison, effets de substituant., Introduction Nitric oxide (NO) is a free-radical gas and one of the smallest known biologically active messenger molecules, which plays key roles in regulating a diverse range of physiological processes, [...]