25 research outputs found
Refléter la Diversité Culturelle de sa Clientèle : Les Clés d'une Image de Marque Inclusive et Performante
No full textLe secteur de l'élevage en Tunisie se caractérise par une forte diversité culturelle, reflétée dans les traditions, pratiques et savoir-faire des exploitants. L'objectif de cette étude est d'analyser empiriquement comment cette diversité culturelle perçue chez les éleveurs façonne l'image et la notoriété d’une entreprise, leadeur de l'alimentation animale. À travers une enquête menée auprès d'un échantillon représentatif de 300 éleveurs tunisiens, visant à évaluer le niveau de diversité culturelle perçue, examiner son impact sur les dimensions de l'image de marque et identifier les leviers de valorisation de cette diversité. Les résultats montrent que la diversité culturelle est fortement ancrée dans les pratiques des éleveurs et constitue un élément clé de leur identité. Cette diversité a un impact positif significatif sur la notoriété, la qualité perçue et la personnalité de la marque. Les éleveurs sont particulièrement sensibles aux initiatives de l'entreprise visant à préserver et valoriser ces patrimoines locaux, telles que le soutien aux savoir-faire traditionnels, le développement de produits adaptés aux spécificités régionales ou encore la mise en avant des producteurs dans la communication
Bridging the Employability Gap Among Recent University Graduates in Tunisia: Mitigating Mismatch Between Acquired Skills and Real Labor Market Needs
No full textOur aim is to highlight on the mismatch between acquired skills and the real needs of the Tunisian labor market, while discussing the case study of experience of Higher Institute of Technological Studies of Kef (ISET Kef), in terms of improving the employability rate of its students according to real needs in the north-west of country. Within the framework of this study, we have opted for a descriptive approach based on data obtained through two surveys carried out by ISET Kef, in January 2022. A survey was conducted among 100 graduates, at least one year after graduation. A second field survey was carried out with 13 industrial and agricultural companies based in the Kef governorate, to understand which skills really need to be developed during university studies. The employability rate of ISET Kef’s graduates is declining from one year to the next. The main factors determining the “employability gap” among recent university graduates include poor coordination between the higher educational institutions and employers, absence of quality training programs, low entrepreneurial and innovative opportunities, as well as underinvestment in research and development
La réussite entrepreneuriale : Révéler le pouvoir des structures d’appui pour transformer les visions en projets d'entreprise tangibles en Tunisie : Étude de cas les jeunes entrepreneurs du gouvernorat du Kef
No full textCette étude vise à évaluer l'impact des différentes structures d'appui entrepreneurial sur la capacité des entrepreneurs à concrétiser leurs visions en projets d'entreprise viables dans le gouvernorat du Kef en Tunisie. Une approche quantitative a été adoptée, avec la collecte de données via une enquête administrée auprès d'un échantillon de 224 entrepreneurs. Les résultats obtenus montrent que certains éléments de l'écosystème entrepreneurial ont un impact positif et significatif. L'intégration à des réseaux professionnels et communautés, l'accès à des espaces de travail collaboratifs, la participation à des programmes d'incubation/accélération, ainsi que l'accès au financement, facilitent la transformation des visions entrepreneuriales en projets concrets. En revanche, l'accompagnement de mentors/coachs et le suivi post-création ont un impact plus limité sur la réussite entrepreneuriale. Ces résultats soulignent l'importance de renforcer certains leviers clés de l'écosystème entrepreneurial afin de mieux soutenir le développement de projets d'entreprise durables dans le gouvernorat du Kef
Stability of receding traveling waves for a fourth order degenerate parabolic free boundary problem
No full text Consider the thin-film equation h t +(hh yyy ) y =0 with a zero contact angle at the free boundary, that is, at the triple junction where liquid, gas, and solid meet. Previous results on stability and well-posedness of this equation have focused on perturbations of equilibrium-stationary or self-similar profiles, the latter eventually wetting the whole surface. These solutions have their counterparts for the second-order porous-medium equation h t −(h m ) yy =0, where m>1 is a free parameter. Both porous-medium and thin-film equation degenerate as h↘0, but the porous-medium equation additionally fulfills a comparison principle while the thin-film equation does not. In this note, we consider traveling waves h=[Formula presented]x 3 +νx 2 for x≥0, where x=y−Vt and V,ν≥0 are free parameters. These traveling waves are receding and therefore describe de-wetting, a phenomenon genuinely linked to the fourth-order nature of the thin-film equation and not encountered in the porous-medium case as it violates the comparison principle. The linear stability analysis leads to a linear fourth-order degenerate-parabolic operator for which we prove maximal-regularity estimates to arbitrary orders of the expansion in x in a right-neighborhood of the contact line x=0. This leads to a well-posedness and stability result for the corresponding nonlinear equation. As the linearized evolution has different scaling as x↘0 and x→∞ the analysis is more intricate than in related previous works. We anticipate that our approach is a natural step towards investigating other situations in which the comparison principle is violated, such as droplet rupture. Accepted author manuscriptAnalysi
Antioxidant Status and Oxidative Stress at Rest and in Response to Acute Exercise in Judokas and Sedentary Men
No full textEl Abed, K, Rebai, H, Bloomer, RJ, Trabelsi, K, Masmoudi, L, Zbidi,A, Sahnoun, Z, Hakim, and A Tabka, Z. Antioxidant status andoxidative stress at rest and in response to acute exercise injudokas and sedentary men. J Strength Cond Res 25(9): 2400-2409, 2011. It is well recognized that acute strenuous exercise is accompanied by an increase in free-radical production andsubsequent oxidative stress, in addition to changes in blood antioxidant status. Chronic exercise provides protection against exercise-induced oxidative stress by upregulating endogenous antioxidant defense systems. Little is known regarding the rotective effect afforded by judo exercise. Therefore, we determined antioxidant and oxidative stress biomarkers at rest and in response to acute exercise in 10 competitive judokas and 10 sedentary subjects after mixed exercise (anaerobic followed by aerobic). The subjects performed a Wingate test, followed by 30 minutes of aerobic exercise performed at 60% of maximal aerobic power. Blood samples were taken, by an intravenous catheter, at rest (R), immediately after the physical exercise (P0), and at 5 (P5), 10 (P10), and 20 (P20) minutes postexercise. The measured parameters included the activity of the antioxidant enzymes superoxide dismutase, glutathione peroxidase, and glutathione reductase, in addition to a-tocopherol, and total antioxidant status. Malondialdehyde was measured as a representation of lipid peroxidation. At rest, the judokas had higher values for all antioxidant and oxidative stress markers as compared to the sedentary subjects (p \u3c 0.05). Plasma concentrations of all parameters except for a-tocopherol increased significantly above resting values for both the judokas and sedentary subjects (p \u3c 0.05) and remained elevated at 20minutes postexercise. A significant postexercise decrease was observed for a-tocopherol (p \u3c 0.05) at P20 for judokas and at P5 for sedentary subjects. These data indicate that competitive judo athletes have higher endogenous antioxidant protection compared to sedentary subjects. However, both groups of subjects experience an increase in exercise-induced oxidative stress that is not different. © 2011 National Strength and Conditioning Association
Disciplinary Interaction Variable Elimination (DIVE) Approach for MDO
No full textFor multi-disciplinary optimization, we present a three level variables elimination approach involving, system level design variables Z, output variables Yi of discipline i, for interaction with other disciplines and private variables Xi of discipline i. We first eliminate the private variables Xi by using meta models for each discipline. The output variables Yi of discipline i are optimal with respect to its private variables X_i, for discipline specific objective function. Then an equilibrium system between interaction variables Y_i is solved. This system is viewed as state equations. This allows elimination of interaction variables Yi using classical approaches like adjoint method. The main advantage of this approach is to accurately satisfy the state equation of the system. After elimination of interaction variables, a system level optimization problem restricted to variables Z, is solved. The reliability of each meta model is checked at optimal point. If the optimal point is on the boundary of the validity domain of particular meta model, then a new meta model for that particular discipline centered around the optimal point is created and the optimization cycle is reiterated with new meta model. We demonstrate our approach for two MDO test cases, problem of combustion of Propane and design of supersonic business jet
Sharp Adams inequalities with exact growth conditions on metric measure spaces and applications
No full textAdams inequalities with exact growth conditions are derived for Riesz-like
potentials on metric measure spaces. The results extend and improve those
obtained recently on by the second author, for Riesz-like
convolution operators. As a consequence, we will obtain new sharp
Moser-Trudinger inequalities with exact growth conditions on , the
Heisenberg group, and Hadamard manifolds. On such inequalities
will be used to prove the existence of radial ground states solutions for a
class of quasilinear elliptic equations, extending results due to Masmoudi and
Sani.Comment: 61 pages. In v2 several typos and a few small errors were corrected.
Minor changes in a few places. To appear in Math. Annale
Etude exploratoire des processus et modèles d'incubation en entrepreneuriat : cas des pépinières tunisiennes
No full textThe exploration of the incubation phenomena aims at replying to the questions on different stages of the incubation process and on the evolution of the incubates entrepreneurial configurations during this process. The first part of this doctoral grade work is devoted to the emergence of the incubation thematic within the Entrepreneurship field. It covers the broad questions concerning : the explosion of the researches in Entrepreneurship and the development of works on enterprise creation support ; the evolution of the Litterature on incubation phenomena ; the distinction between the concepts of an Incubator and of a Sced-bed; the conceptualisation of the process and of the models of incubation; - the modalities of the incubation configurations appreciation.The second part allows us to enter into the heart of the Tunisian incubation structures. It is devolved, firstly, to the exploration of the incubation processes and models as it regards theTunisian enterprise and project seed-beds. Secondly, it concerns the intrinsic characteristics of the Tunisian incubates. Thirdly. The evolution of the entrepreneurial configurations during the incubation process is explored. Finally. it concludes on the performance evaluation modalities of the incubation structures.Basing on this research, the author distinguishes several incubation processes and latent models. These models, yet, are given an impulse by a set of variables related to the incubation structures' particularises and lo the incubates' and their project's characteristics.L'exploration du phénomène d'incubation a pour objectif de répondre aux questions qui portent sur les différentes étapes du processus d'incubation et sur l'évolution des configurations entrepreneuriales des incubés au cours de ce processus. La première partie de ce travail doctoral, porte sur l'émergence de la thématique d'incubation dans le champ de l'entrepreneuriat. Elle couvre les grandes questions concernant : l'éclatement des recherches en entrepreneuriat et le développement des travaux sur l'appui à la création d'entreprises ;l'évolution de la littérature sur le phénomène d'incubation ; la distinction entre les concepts d'incubateur et de pépinière ;la conceptualisation du processus et des modèles d'incubation ; les modalités d'appréciation des configurations d'incubation. La deuxième partie, nous fait entrer dans le cœur des structures d'incubation tunisiennes. Elle a été consacrée, en premier lieu, à l'exploration des processus et des modèles d'incubation des pépinières de projets et d'entreprises tunisiennes. En deuxième lieu, aux caractéristiques intrinsèques des incubés tunisiens. En troisième lieu, à l'évolution des configurations entrepreneuriales tout au long du processus d'incubation. Enfin, aux modalités d'évaluation de la performance des structures d'incubation. De cette recherche, nous avons pu distinguer plusieurs processus d'incubation et des modèles sous-jacents. Ces modèles sont, toutefois, impulsés par un ensemble de variables liées aux spécificités des structures d'incubation et aux caractéristiques des incubés et de leur projet
Propriétés physico-chimiques et performances mécaniques de bétons renforcés par des fibres végétales
No full textCette étude vise à évaluer la capacité des fibres (chanvre et alfa) à améliorer les propriétés mécaniques du béton, dans le but de créer un béton respectueux de l'environnement. Les bétons ont été incorporés avec des teneurs de 0.25 %, 0.5 % et 1% (en volume) en fibres de chanvre, plus une dose de 0.5 % (en volume) de fibres d'alfa et ainsi qu’un béton ordinaire. Les résultats montrent que l'utilisation des fibres de chanvre et d'alfa permet une meilleure augmentation de la résistance à la traction par fendage par rapport au béton ordinaire. De plus, l'augmentation de la résistance à la flexion pour le béton de fibres de chanvre avec une teneur optimale de 0.25%. Aussi, le module d'élasticité dynamique du HFC-0.25 est proche ou égal à celui du béton ordinaire Nous concluons que les fibres végétales de chanvre et d'alfa sont des candidats potentiels pour produire du béton vert.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Vanishing Viscosity Limit for Incompressible Viscoelasticity in Two Dimensions
No full textThis paper studies the inviscid limit of the two-dimensional incompressible viscoelasticity, which is a system coupling a Navier-Stokes equation with a transport equation for the deformation tensor. The existence of global smooth solutions near the equilibrium with a fixed positive viscosity was known since the work of [35]. The inviscid case was solved recently by the second author [28]. While the latter was solely based on the techniques from the studies of hyperbolic equations, and hence the two-dimensional problem is in general more challenging than that in higher dimensions, the former was relied crucially upon a dissipative mechanism. Indeed, after a symmetrization and a linearization around the equilibrium, the system of the incompressible viscoelasticity reduces to an incompressible system of damped wave equations for both the fluid velocity and the deformation tensor. These two approaches are not compatible. In this paper, we prove global existence of solutions, uniformly in both time t ∈ [0, +∞) and viscosity μ ≥ 0. This allows us to justify in particular the vanishing viscosity limit for all time. In order to overcome difficulties coming from the incompatibility between the purely hyperbolic limiting system and the systems with additional parabolic viscous perturbations, we introduce in this paper a rather robust method that may apply to a wide class of physical systems of similar nature. Roughly speaking, the method works in the two-dimensional case whenever the hyperbolic system satisfies intrinsically a “strong null condition.” For dimensions not less than three, the usual null condition is sufficient for this method to work.</p
