Bounded Guaranteed Algorithms for Concave Impurity Minimization Via Maximum Likelihood

Partitioning algorithms play a key role in many scientific and engineering disciplines. A partitioning algorithm divides a set into a number of disjoint subsets or partitions. Often, the quality of the resulted partitions is measured by the amount of impurity in each partition, the smaller impurity the higher quality of the partitions. In general, for a given impurity measure specified by a function of the partitions, finding the minimum impurity partitions is an NP-hard problem. Let $M$ be the number of $N$-dimensional elements in a set and $K$ be the number of desired partitions, then an exhaustive search over all the possible partitions to find a minimum partition has the complexity of $O(K^M)$ which quickly becomes impractical for many applications with modest values of $K$ and $M$. Thus, many approximate algorithms with polynomial time complexity have been proposed, but few provide bounded guarantee. In this paper, an upper bound and a lower bound for a class of impurity functions are constructed. Based on these bounds, we propose a low-complexity partitioning algorithm with bounded guarantee based on the maximum likelihood principle. The theoretical analyses on the bounded guarantee of the algorithms are given for two well-known impurity functions Gini index and entropy. When $K \geq N$, the proposed algorithm achieves state-of-the-art results in terms of lowest approximations and polynomial time complexity $O(NM)$. In addition, a heuristic greedy-merge algorithm having the time complexity of $O((N-K)N^2+NM)$ is proposed for $K<N$. Although the greedy-merge algorithm does not provide a bounded guarantee, its performance is comparable to that of the state-of-the-art methods. Our results also generalize some well-known information-theoretic bounds such as Fano's inequality and Boyd-Chiang's bound.Comment: 13 pages, 6 figure

Can EEG-devices differentiate attention values between incorrect and correct solutions for problem-solving tasks?

The affective state of an individual can be determined using physiological parameters; an important metric that can then be extracted is attention. Looking more closely at compact EEGs, algorithms have been implemented in such devices that can measure the attention and other affective states of the user. No information about these algorithms is available; are these feature classification algorithms accurate? An experiment was conducted with 23 subjects who utilized a pedagogical agent to learn the syntax of the programming language Java while having their attention measured by the NeuroSky MindWave Mobile 2. Using a concurrent validity approach, the attention values measured were compared to band powers, as well as measures of task performance. The results of the experiment were in part successful and supportive of the claim that the EEG device’s attention algorithm does in fact represent a user’s attention accurately. The results of the analysis based on raw data captured from the device were consistent with previous literature. Inconclusive results were obtained relating to task performance and attention.Peer Reviewe

Advancing Wound Filling Extraction on 3D Faces: A Auto-Segmentation and Wound Face Regeneration Approach

Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications. In this paper, we propose an efficient approach for automating 3D facial wound segmentation using a two-stream graph convolutional network. Our method leverages the Cir3D-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss functions. To achieve accurate segmentation, we conducted thorough experiments and selected a high-performing model from the trained models. The selected model demonstrates exceptional segmentation performance for complex 3D facial wounds. Furthermore, based on the segmentation model, we propose an improved approach for extracting 3D facial wound fillers and compare it to the results of the previous study. Our method achieved a remarkable accuracy of 0.9999986\% on the test suite, surpassing the performance of the previous method. From this result, we use 3D printing technology to illustrate the shape of the wound filling. The outcomes of this study have significant implications for physicians involved in preoperative planning and intervention design. By automating facial wound segmentation and improving the accuracy of wound-filling extraction, our approach can assist in carefully assessing and optimizing interventions, leading to enhanced patient outcomes. Additionally, it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3D bioprinting for printing skin tissue implants. Our source code is available at \url{https://github.com/SIMOGroup/WoundFilling3D}

Application of Self-Supervised Learning to MICA Model for Reconstructing Imperfect 3D Facial Structures

In this study, we emphasize the integration of a pre-trained MICA model with an imperfect face dataset, employing a self-supervised learning approach. We present an innovative method for regenerating flawed facial structures, yielding 3D printable outputs that effectively support physicians in their patient treatment process. Our results highlight the model's capacity for concealing scars and achieving comprehensive facial reconstructions without discernible scarring. By capitalizing on pre-trained models and necessitating only a few hours of supplementary training, our methodology adeptly devises an optimal model for reconstructing damaged and imperfect facial features. Harnessing contemporary 3D printing technology, we institute a standardized protocol for fabricating realistic, camouflaging mask models for patients in a laboratory environment

Static and Dynamic Analysis of Piezoelectric Laminated Composite Beams and Plates

In this chapter, the mechanical behavior analysis of piezoelectric laminated composite beams and plates is influenced subjected to static, dynamic, and aerodynamic loads. Algorithm for dynamic, stability problem analysis and vibration control of laminated composite beams and plates with piezoelectric layers is presented. In addition, numerical calculations, considering the effect of factors on static, dynamic, and stability response of piezoelectric laminated composite beams and plates are also clearly presented. The content of this chapter can equip readers with the knowledge used to calculate the static, dynamic, and vibration control of composite beams, panels made of piezoelectric layers applied in the field different techniques

Numerical investigation of force transmission in granular media using discrete element method

In this paper, a numerical Discrete Element Method (DEM) model was calibrated to investigate the transmission of force in granular media. To this aim, DEM simulation was performed for reproducing the behavior of a given granular material under uniform compression. The DEM model was validated by comparing the obtained shear stress/normal stress ratio with results published in the available literature. The network of contact forces was then computed, showing the arrangement of the material microstructure under applied loading. The number and distribution of the contacts force were also examined statistically, showing that the macroscopic behavior of the granular medium highly depended on the force chain network. The DEM model could be useful in exploring the mechanical response of granular materials under different loadings and boundary conditions

A review of technologies for collaborative online information seeking: On the contribution of collaborative argumentation

In everyday life, people seek, evaluate, and use online sources to underpin opinions and make decisions. While education must promote the skills people need to critically question the sourcing of online information, it is important, more generally, to understand how to successfully promote the acquisition of any skills related to seeking online information. This review outlines technologies that aim to support users when they collaboratively seek online information. Upon integrating psychological–pedagogical approaches on trust in and the sourcing of online information, argumentation, and computer-supported collaborative learning, we reviewed the literature (N = 95 journal articles) on technologies for collaborative online information seeking. The technologies we identified either addressed collaborative online information seeking as an exclusive process for searching for online information or, alternatively, addressed online information seeking within the context of a more complex learning process. Our review was driven by three main research questions: We aimed to understand whether and how the studies considered 1) the role of trust and critical questioning in the sourcing of online information, 2) the learning processes at play when information seekers engage in collaborative argumentation, and 3) what affordances are offered by technologies that support users’ collaborative seeking of online information. The reviewed articles that focused exclusively on technologies for seeking online information primarily addressed aspects of cooperation (e.g., task management), whereas articles that focused on technologies for integrating the processes of information seeking into the entire learning processes instead highlighted aspects of collaborative argumentation (e.g., exchange of multiple perspectives and critical questioning in argumentation). Seven of the articles referred to trust as an aspect of seekers’ sourcing strategies. We emphasize how researchers’, users’, and technology developers’ consideration of collaborative argumentation could expand the benefits of technological support for seeking online information.Peer Reviewe

Robust Adaptive Cerebellar Model Articulation Controller for 1-DOF Nonlaminated Active Magnetic Bearings

This paper presents a robust adaptive cerebellar model articulation controller (RACMAC) for 1-DOF nonlaminated active magnetic bearings (AMBs) to achieve desired positions for the rotor using a robust sliding mode control based. The dynamic model of 1-DOF nonlaminated AMB is introduced in fractional order equations. However, it is challenging to design a controller based on the model\u27s parameters due to undefined components and external disturbances such as eddy current losses in the actuator, external disturbance, variant parameters of the model while operating. In order to tackle the problem, RACMAC, which has a cerebellar model to estimate nonlinear disturbances, is investigated to resolve this problem. Based on this estimation, a robust adaptive controller that approximates the ideal and compensation controllers is calculated. The online parameters of the neural network are adjusted using Lyapunov\u27s stability theory to ensure the stability of system. Simulation results are presented to demonstrate the effectiveness of the proposed controller.The simulation results indicate that the CMAC multiple nonlinear multiple estimators are close to the actual nonlinear disturbance value, and the effectiveness of the proposed RACMAC method compared with the FOPID and SMC controllers has been studied previously

LES RÔLES DE L'ORGANISATION PAYSANNE ET DE L'ACTION COLLECTIVE POUR LE RENFORCEMENT DES FILIÈRES DE COMMERCIALISATION DES PRODUITS DE «SPÉCIALITÉ LOCALE» LE CAS DU LONGANE «LONG» DE LA PROVINCE DE HUNGYEN AU VIETNAME

N° ISBN - 978-2-7380-1284-5International audienceLe Vietnam est actuellement engagé dans un processus d'intégration économique internationale issue notamment de son adhésion récente à l'OMC. Ce processus inclut une ouverture croissante du secteur agro-alimentaire domestique à la concurrence des produits importés. Les exploitations agricoles familiales sont particulièrement fragilisées par ce nouveau contexte, en raison de le petite taille et du morcellement des superficies cultivables. Les moyens de renforcer la compétitivité des produits issues de l'agriculture familiale constitue ainsi une des priorités pour les recherches vietnamiennes en économie agricole. Au Vietnam, le longane “Long” produit dans la province de Hungyen est un produit de spécialité locale, c'est-à-dire dont la qualité spécifique est reconnue par une partie des consommateurs. Néanmoins, le manque d'action collective entre les exploitations agricoles familiales fragilisent les performances de cette filière face aux longanes des autres régions du Vietnam et les longanes importés. Cet article présente les expériences d'appui pour le renforcement de la filière du longane “Long” de la province de Hungyen au Vietnam vers le développement de l'indication géographique. Grâce à l'appui de GTZ (German Technical Cooperation) et de l'IPSARD (Institut de politique et de stratégie pour l'agriculture et le développement rural), la coopérative de longane Long Hongnam, qui consiste en une organisation de producteurs et de commerçants, a été mise sur pied en 2006. La coopérative a permis la mise en place des actions collectives suivantes: l'application d'un itinéraire technique de production amélioré incluant le respect de certaines bonnes pratiques agricoles locales (Good agricultural practices ou GAP), et la mise sur pied d'un espace de dialogue avec les commerçants. Grace à ce dispositif, les producteurs ont pu augmenter leur prix du vente, améliorer l'homogénéité de la qualité des produits, et améliorer leur revenu. La durabilité de ce dispositif est discutée. L'article fait le bilan des forces et faiblesses de ces strategies de soutien a l'action collective