Spectral isometries on non-simple C*-algebras

We prove that unital surjective spectral isometries on certain non-simple unital C*-algebras are Jordan isomorphisms. Along the way, we establish several general facts in the setting of semisimple Banach algebras.Comment: 7 pages; paper available since July 201

LA COMPÉTENCE DE L'AUDITEUR COMPTABLE VUE PAR LES EXPERTS COMPTABLES

International audienceCet article aborde la problématique de mesure de la notion de compétence dans le domaine de l'audit comptable. Un examen du processus de son apprentissage permet de discuter à propos de son impact sur l'audit. Pour statuer, cet article se base sur les résultats d'une étude qualitative menée auprès de 20 experts comptables tunisiens chefs de cabinets d'expertise comptable et d'audit. La compétence de l'auditeur comptable est liée à l'accomplissement de missions compliquées. Le degré de structuration du cabinet peut favoriser ou freiner le développement de la compétence de l'auditeur. Le chiffre d'affaire, l'effectif et la qualité de l'organisation du cabinet peuvent constituer des mesures fiables de la compétence de son propriétaire individuel ou des associés

Using a conic bundle method to accelerate both phases of a quadratic convex reformulation

We present algorithm MIQCR-CB that is an advancement of method MIQCR~(Billionnet, Elloumi and Lambert, 2012). MIQCR is a method for solving mixed-integer quadratic programs and works in two phases: the first phase determines an equivalent quadratic formulation with a convex objective function by solving a semidefinite problem $(SDP)$, and, in the second phase, the equivalent formulation is solved by a standard solver. As the reformulation relies on the solution of a large-scale semidefinite program, it is not tractable by existing semidefinite solvers, already for medium sized problems. To surmount this difficulty, we present in MIQCR-CB a subgradient algorithm within a Lagrangian duality framework for solving $(SDP)$ that substantially speeds up the first phase. Moreover, this algorithm leads to a reformulated problem of smaller size than the one obtained by the original MIQCR method which results in a shorter time for solving the second phase. We present extensive computational results to show the efficiency of our algorithm

LA COMPÉTENCE DE L'AUDITEUR COMPTABLE VUE PAR LES EXPERTS COMPTABLES

Cet article aborde la problématique de mesure de la notion de compétence dans le domaine de l'audit comptable. Un examen du processus de son apprentissage permet de discuter à propos de son impact sur l'audit. Pour statuer, cet article se base sur les résultats d'une étude qualitative menée auprès de 20 experts comptables tunisiens chefs de cabinets d'expertise comptable et d'audit. La compétence de l'auditeur comptable est liée à l'accomplissement de missions compliquées. Le degré de structuration du cabinet peut favoriser ou freiner le développement de la compétence de l'auditeur. Le chiffre d'affaire, l'effectif et la qualité de l'organisation du cabinet peuvent constituer des mesures fiables de la compétence de son propriétaire individuel ou des associés.Audit; Compétence; Approche comportementale; Approche cognitive; Théorie d'acquisition des skills; Décision; Jugement; Difficultés comptables

Critical Analysis of Internal Audit Independence: International Literature

This article provides an analysis of internal auditor independence framework by proposing and comparing the thesis of independence as a social construct and its antithesis as a myth. Extensive reviews of empirical research allow us to evaluate the key levers of audit committees, and the conditions of effectiveness of these bodies. Independence of the internal auditor is described as essential to sit his assessments. However, his position as an employee, with a subordination agreement with an employer, may affect his own judgment. Such a conflict threatens the independence of the internal auditor through its programming independence, investigation and / or reports. An "optimal" level of independence is built. It is clear that an independent audit committee, accessible and / or competent often contributes to the preservation of the independence of the internal auditor. The ambiguity of roles between assurance and consulting, not recognized as such by internal auditors may impair independence. The limitations and possible extensions of this line of research are discussed.This article provides an analysis of internal auditor independence framework by proposing and comparing the thesis of independence as a social construct and its antithesis as a myth. Extensive reviews of empirical research allow us to evaluate the key levers of audit committees, and the conditions of effectiveness of these bodies. Independence of the internal auditor is described as essential to sit his assessments. However, his position as an employee, with a subordination agreement with an employer, may affect his own judgment. Such a conflict threatens the independence of the internal auditor through its programming independence, investigation and / or reports. An "optimal" level of independence is built. It is clear that an independent audit committee, accessible and / or competent often contributes to the preservation of the independence of the internal auditor. The ambiguity of roles between assurance and consulting, not recognized as such by internal auditors may impair independence. The limitations and possible extensions of this line of research are discussed

Le rapport portant sur les éléments du contrôle interne: aller au-delà du reporting réglementaire et analyser les discours

AbstractThis article investigates the internal control information inserted in management report through an analysis of contents of reports prepared by the presidents of the main Tunisians companies listed in the stock exchange. The absence of precision on the contents and the character places the transmitter in front of a freedom of action and invites us to question about the rigo of this information in financial transparency. Our research highlights the descriptive vision of reports anchored in particularly by procedures of approval and follow-up of the risks. A particular accent is put on the corporate governance and its mechanisms

Distribution and phenotypic variability aspects of some quantitiative traits among durum wheat accessiions

A durum wheat (Triticum durum Desf.) collection with 111 accessions represents a large part of the collection of Triticeae species in Tunisia were evaluated for six qualitative traits: seed colour, seed size, glume colour, glume pubescence, spike density and beak length. Distribution of traits showed that this germoplasm was dominated by dense spike, white and glabre glume, long beak, brown and large grain. Phenotypic diversity is determined by the index Shannon-Weaver (H’). This index calculated for each parameter revealed that spike density (H’ =0.86),glume pubescence (H’ =0.80) and glume colour (H’ =0.79) showed the best diversity index. Seed size showed the weakest index (H’ =0.69) which indicated a low phenotypic variability for this parameter. This durum wheat germoplasm presented an average of diversity index about 0.77, showing a large diversity of this collection. These values showed that the germoplasm has a relatively important diversity, confirming that Tunisia is one of the principal durum wheat secondary centres of diversification. This genetic diversity can be exploited in improvementprogrammes