Singular limits for 4-dimensional semilinear elliptic problems with exponential nonlinearity

Using some nonlinear domain decomposition method, we prove the existence of singular limits for solution of semilinear elliptic problems with exponential nonlinearity.Comment: 29 page

Low-temperature anharmonicity of barium titanate: a path-integral molecular dynamics study

We investigate the influence of quantum effects on the dielectric and piezoelectric properties of barium titanate in its (low-temperature) rhombohedral phase, and show the strongly anharmonic character of this system even at low temperature. For this purpose, we perform path-integral molecular-dynamics simulations under fixed pressure and fixed temperature, using an efficient Langevin thermostat-barostat, and an effective hamiltonian derived from first-principles calculations. The quantum fluctuations are shown to significantly enhance the static dielectric susceptibility (~ by a factor 2) and the piezoelectric constants, reflecting the strong anharmonicity of this ferroelectric system even at very low temperature. The slow temperature-evolution of the dielectric properties observed below ~ 100 K is attributed (i) to zero-point energy contributions and (ii) to harmonic behavior if quantum effects are turned off.Comment: submitted to Phys. Rev.

Hypomorphy of graphs up to complementation

Let $V$ be a set of cardinality $v$ (possibly infinite). Two graphs $G$ and $G'$ with vertex set $V$ are {\it isomorphic up to complementation} if $G'$ is isomorphic to $G$ or to the complement $\bar G$ of $G$. Let $k$ be a non-negative integer, $G$ and $G'$ are {\it $k$-hypomorphic up to complementation} if for every $k$-element subset $K$ of $V$, the induced subgraphs $G\_{\restriction K}$ and $G'\_{\restriction K}$ are isomorphic up to complementation. A graph $G$ is {\it $k$-reconstructible up to complementation} if every graph $G'$ which is $k$-hypomorphic to $G$ up to complementation is in fact isomorphic to $G$ up to complementation. We give a partial characterisation of the set $\mathcal S$ of pairs $(n,k)$ such that two graphs $G$ and $G'$ on the same set of $n$ vertices are equal up to complementation whenever they are $k$-hypomorphic up to complementation. We prove in particular that $\mathcal S$ contains all pairs $(n,k)$ such that $4\leq k\leq n-4$. We also prove that 4 is the least integer $k$ such that every graph $G$ having a large number $n$ of vertices is $k$-reconstructible up to complementation; this answers a question raised by P. Ill

LA DIVULGATION DE L'INFORMATION ENVIRONNEMENTALE DANS LES RAPPORTS ANNUELS : UNE ETUDE COMPARATIVE DES MULTINATIONALES AMERICAINES ET EUROPEENNES

Ce travail de recherche vise à comparer les informations environnementales divulguées dans les rapports annuels des entreprises multinationales américaines et européennes. Eventuellement, nous essayons de mettre en évidence les facteurs explicatifs des différences en matière de communication écologique. Après avoir analysé les rapports annuels, de 72 entreprises multinationales à l'aide d'un indice développé et validé par Wiseman (1982), nous trouvons que les multinationales européennes divulguent plus d'informations environnementales que les multinationales américaines. Nous trouvons également que la nationalité d'une entreprise multinationale (américaine, européenne) a un effet faible sur le niveau de divulgation écologique. Ces résultats apportent leurs contributions aux études de plus en plus nombreuses sur l'harmonisation comptable.Communication; information environnementale; rapport annuel; entreprise multinationale

The Mediating Role of the Balanced Scorecard in the Relationship Between Internal Control and the Financial Reports Quality

Purpose: this study aims to measurement the role of the mediating of performance evaluation according to the Balanced Scorecard (BS) in the relationship between internal control (IC) and the financial reports quality (FRQ) in Iraqi commercial banks.   Theoretical framework: The general framework of the study includes three variables, including performance evaluation according to the BS, in the relationship between IC and the FRQ.   Design/methodology/approach: We are used the descriptive-analytical approach. Iraqi commercial banks were identified as a research community, Banks (Bank of Baghdad, Commercial Bank of Iraq, and the Iraqi Investment Bank). It required a survey of the opinions of managers and workers in the banks under study from accountants and auditors, the research sample was represented (managers in all banking departments, consultants, accountants, auditors), (245) forms were distributed and retrieved from them (224) valid for analysis.   Findings: The results showed existence of a significant effect of internal control system (ICS) in enhancing the FRQ.   Research, Practical & Social implications: The use of the BS as a tool can enhance IC and improve the quality of financial reporting for the banks under study.   Originality/value: A few studies investigated the relationship between the studied variables, our study contributes to filling part of the research gap related to the research variables