Priority based round robin (PBRR) CPU scheduling algorithm

This paper introduce a new approach for scheduling algorithms which aim to improve real time operating system CPU performance. This new approach of CPU Scheduling algorithm is based on the combination of round-robin (RR) and Priority based (PB) scheduling algorithms. This solution maintains the advantage of simple round robin scheduling algorithm, which is reducing starvation and integrates the advantage of priority scheduling. The proposed algorithm implements the concept of time quantum and assigning as well priority index to the processes. Existing round robin CPU scheduling algorithm cannot be dedicated to real time operating system due to their large waiting time, large response time, large turnaround time and less throughput. This new algorithm improves all the drawbacks of round robin CPU scheduling algorithm. In addition, this paper presents analysis comparing proposed algorithm with existing round robin scheduling algorithm focusing on average waiting time and average turnaround time

Improved time quantum length estimation for round robin scheduling algorithm using neural network

In most cases, the quantum time length is taken to be fix in all applications that use Round Robin (RR) scheduling algorithm. Many attempts aim to determination of the optimal length of the quantum that results in a small average turnaround time, but the unknown nature of the tasks in the ready queue make the problem more complicated: Considering a large quantum length makes the RR algorithm behave like a First Come First Served (FIFO) scheduling algorithm, and a small quantum length cause high number of contexts switching. In this paper we propose a RR scheduling algorithm based on Neural Network Models for predicting the optimal quantum length which lead to a minimum average turnaround time. The quantum length depends on tasks burst times available in the ready queue. Rather than conventional traditional methods using fixed quantum length, this one giving better results by minimizing the average turnaround time for almost any set of jobs in the ready queue

The Comparison between Circadian Oscillators in Mouse Liver and Pituitary Gland Reveals Different Integration of Feeding and Light Schedules

The mammalian circadian system is composed of multiple peripheral clocks that are synchronized by a central pacemaker in the suprachiasmatic nuclei of the hypothalamus. This system keeps track of the external world rhythms through entrainment by various time cues, such as the light-dark cycle and the feeding schedule. Alterations of photoperiod and meal time modulate the phase coupling between central and peripheral oscillators. In this study, we used real-time quantitative PCR to assess circadian clock gene expression in the liver and pituitary gland from mice raised under various photoperiods, or under a temporal restricted feeding protocol. Our results revealed unexpected differences between both organs. Whereas the liver oscillator always tracked meal time, the pituitary circadian clockwork showed an intermediate response, in between entrainment by the light regimen and the feeding-fasting rhythm. The same composite response was also observed in the pituitary gland from adrenalectomized mice under daytime restricted feeding, suggesting that circulating glucocorticoids do not inhibit full entrainment of the pituitary clockwork by meal time. Altogether our results reveal further aspects in the complexity of phase entrainment in the circadian system, and suggest that the pituitary may host oscillators able to integrate multiple time cues

Clinical epidemiology of primary tumors of the central nervous system and gliomas specifically

Les gliomes ont des conséquences dévastatrices. La morbidité et la mortalité sont élevées. Les gliomes représentent un groupe hétérogène complexe d'entités pathologiques et aucune cause n'a été identifiée pour la majorité des gliomes. Les données épidémiologiques varient d'une étude à l'autre. Le nombre de chaque sous-type histologique est trop petit, même pour un grand centre de neurochirurgie, pour permettre une bonne recherche sur chaque sous-type de gliome. Les spécificités oncologiques et cliniques (épilepsie, troubles cognitifs, troubles moteurs, etc.) nécessitent une prise en charge et une analyse spécifique. De plus, il est important de recueillir et d'enregistrer tous les nouveaux cas et le suivi sur une grande région ou un pays entier pour permettre des études fondamentales et cliniques de qualité. En effet, les études en population sont la seule façon de connaitre l'impact en pratique des différentes thérapeutiques effectuées. Les sociétés françaises impliquées en neuro-oncologie (Société Française de Neurochirurgie, Société Française de Neuropathologie, Association des Neuro-Oncologues d'Expression Française) ont récemment créé le Recensement national histologique des tumeurs primitives du système nerveux central (RnhTPSNC) ou French Brain Tumor DataBase (FBTDB) en anglais. L'objectif principal du RnhTPSNC est d'enregistrer de manière prospective tous les cas incidents de tumeur primitive du système nerveux central (TPSNC), en France, pour lesquels le diagnostic histologique est confirmé (1-3). Les objectifs à long terme du RnhTPSNC sont de créer un registre histologique et un réseau national pour : (1) réaliser des études épidémiologiques, (2) mettre en place une base de données pour favoriser toute étude clinique ou fondamentale à grande échelle, (3) permettre l'évaluation des pratiques médicales d'une région ou du pays tout entier, (4) harmoniser et optimiser la prise en charge médicale des patients atteints de TPSNC. La présente étudiante en thèse, Sonia Zouaoui, concentrera son travail sur les gliomes. D'abord, elle devra recueillir les données des patients, puis analyser les facteurs pronostiques, la survie et les prises en charges oncologiques. Deuxièmement, elle participera à l'étude de la répartition géographique des principaux types de gliomes et à la recherche de facteurs de causaux. Troisièmement, elle procédera à un inventaire du matériel cryopréservé disponible pour la réalisation d'études translationnelles.Gliomas have devastating consequences. Morbidity and mortality are high. Gliomas represent a complex heterogeneous group of pathologic entities and no underlying cause has been identified for the majority of them. Epidemiologic data vary from study to study. The number of each histological subtype is too small, even for a big neurosurgical center, to allow a good research on each subtype of glioma. Oncological and clinical specificities (epilepsy, cognitive disorders, motor impairments, etc) require a specific care and analysis. Indeed, we need to collect and record all new cases and follow up in large area, to allow good basic and clinical studies. Furthermore, population study is the only way to know what clinicians do to the patients, and make possible evaluating the medical care. The French societies involved in Neuro-Oncology (Société Française de Neurochirurgie, Société Française de Neuropathologie, Association des Neuro-Oncologues d'Expression Française) have recently created the French Brain Tumor DataBase (FBTDB). The main objective of the FBTDB is to prospectively record all primary central nervous system tumors (PCNST), in France, for which histological diagnosis is available (1-3). The long-term goals of the FBTDB are to create a histological national registry and a national network to (1) perform epidemiological studies, (2) implement a new database and use it for setting up both clinical and basic research protocols, (3) allow the evaluation of the medical practices of an area or of the entire country, and (4) harmonize the healthcare of patients affected by PCNST at the higher level. The present PhD student, Sonia Zouaoui, will focus her work on gliomas. First, she will collect data, and will analyze prognostic factors, survival and oncological patterns of care for patients with newly diagnosed glioma in France. Secondly, she will participate in the study of geographical distribution of the main types of glioma and in search of causal factors. Thirdly, she will conduct an inventory of cryopreserved material available for translational research

Une approche gestaltiste de la performance de la jeune entreprise technologique innovante

Considérées comme l’un des principaux leviers du développement économique d’un pays, les jeunes entreprises technologiques innovantes (JETI) sont à l’origine de l’introduction de nouvelles technologies, de l’exploration d’opportunités commerciales et de la création des marchés de l’avenir.Malgré l’intérêt considérable porté à la performance des JETI (Jiao et al., 2013 ; Chen, 2009 ; Song et al., 2008), les recherches concernant ses déterminants ont plutôt adopté une approche contingente que gestaltiste, alors que de nombreux travaux soulignent que la pertinence de cette dernière perspective est de pouvoir intégrer divers éléments dans une démarche holiste (Ketchen, Thomas et Snow, 1993 ; Harms et al., 2009 ; Witmeur et Biga Diambeidou, 2010) de manière à dépasser les conflits de l’approche contingente relatifs à l’analyse d’une multitude de relations bivariées (Henninger-Vacher, 1999 ; 2000).L’objectif de cet article est de contribuer à améliorer la compréhension de la performance de la JETI par la proposition d’une modélisation gestaltiste s’inscrivant dans le cadre de l’approche configurationnelle et permettant d’expliquer les différences de performance. Pour y parvenir, une enquête quantitative a été menée auprès d’un échantillon de 95 jeunes entreprises technologiques innovantes (JETI) du secteur des services informatiques en France. Les conclusions de ce travail peuvent alors constituer une grille de lecture permettant d’apporter un éclairage instructif sur les voies privilégiées de la performance de la JETI et faire l’objet auprès des praticiens, de réflexions et d’analyses complémentaires à leurs pratiques voire de développement d’un outil d’aide à la décision à destination des entrepreneurs.Considered one of the main drivers of economic development of a country, the young innovative technological ventures (YITV) are responsible for the introduction of new technologies, exploring business opportunities and the creation of markets for the future.In spite of the considerable interest carried in the performance of YITV (Jiao et al., 2013 ; Chen, 2009 ; Song et al., 2008), research on the determinants have instead adopted a contingency approach that gestalt, while many studies underline the relevance of this latter perspective is to integrate various elements into a holistic approach (Ketchen, Thomas and Snow, 1993 ; Harms et al., 2009 ; Witmeur and Biga Diambeidou, 2010) so as to overcome the conflicts of the contingent approach related to the analysis of a multitude of bivariate relationships (Henninger-Vacher, 1999 ; 2000).The purpose of this research thus is to contribute to a better understanding of the performance of the YITV by the proposal of a gestaltist modeling which joins within the framework of the configurationnel approach. To reach there, a quantitative survey was led with a sample of 95 YITV of the software sector in France. The conclusions of this work can then constitute a key for reading allowing to give an instructive perspective on the privileged ways of the performance of the YITV and to be the object, for the practitioners, of reflections and complementary analyses in their practices even of development of a decision-making tool aimed at the entrepreneurs.Considerado uno de los principales motores del desarrollo económico de un país, las jóvenes empresas innovadoras de tecnología (JEIT), son responsables de la introducción de nuevas tecnologías, la exploración de oportunidades de negocio y la creación de mercados para el futuro.A pesar de un interés considerable en el rendimiento del negocio (Jiao et al., 2013 ; Chen 2009 ; Song et al., 2008), la investigación sobre los determinantes haber vez adoptado un enfoque de contingencia que gestalt, mientras que muchos estudios subrayan la relevancia de esta última perspectiva es integrar diversos elementos en un enfoque holístico (Ketchen, Thomas y Snow, 1993 ; Harms et al., 2009 ; Witmeur y Biga Diambeidou, 2010) con el fin de superar los conflictos del enfoque contingente en el análisis de una multitud de relaciones bivariadas (Henninger-Vacher, 1999 ; 2000).El propósito de este artículo es ayudar a mejorar la comprensión del rendimiento de la (JEIT) por la propuesta de un modelado gestalt está dentro del alcance del enfoque configuracional y para explicar las diferencias en el rendimiento. Para lograr esto, una encuesta cuantitativa se llevó a cabo con una muestra de 95 innovadoras (JEIT) del sector de servicios de TI en Francia. Las conclusiones de este trabajo, entonces puede ser un marco de trabajo para proporcionar información útil sobre las formas preferidas de la actuación de la JEIT y sujeto a los profesionales, reflexiones y análisis aún más sus prácticas aún el desarrollo de una herramienta de ayuda a la decisión para los empresarios

On a Nonlinear Three-Point Subdivision Scheme Reproducing Piecewise Constant Functions

In this article, a nonlinear binary three-point non-interpolatory subdivision scheme is presented. It is based on a nonlinear perturbation of the three-point subdivision scheme: A new three point approximating C2 subdivision scheme, where the convergence and the stability of this linear subdivision scheme are analyzed. It is possible to prove that this scheme does not present Gibbs oscillations in the limit functions obtained. The numerical experiments show that the linear scheme is stable even in the presence of jump discontinuities. Even though, close to jump discontinuities, the accuracy is loosed. This order reduction is equivalent to the introduction of some diffusion. Diffusion is a good property for subdivision schemes when the discontinuities are numerical, i.e., they appear when discretizing a continuous function close to high gradients. On the other hand, if the initial control points come from the discretization of a piecewise continuous function, it can be interesting that the subdivision scheme produces a piecewise continuous limit function. For instance, in the approximation of conservation laws, real discontinuities appear as shocks in the solution. The nonlinear modification introduced in this work allows to attain this objective. As far as we know, this is the first subdivision scheme that appears in the literature with these properties

On a Nonlinear Three-Point Subdivision Scheme Reproducing Piecewise Constant Functions

In this article, a nonlinear binary three-point non-interpolatory subdivision scheme is presented. It is based on a nonlinear perturbation of the three-point subdivision scheme: A new three point approximating C2 subdivision scheme, where the convergence and the stability of this linear subdivision scheme are analyzed. It is possible to prove that this scheme does not present Gibbs oscillations in the limit functions obtained. The numerical experiments show that the linear scheme is stable even in the presence of jump discontinuities. Even though, close to jump discontinuities, the accuracy is loosed. This order reduction is equivalent to the introduction of some diffusion. Diffusion is a good property for subdivision schemes when the discontinuities are numerical, i.e., they appear when discretizing a continuous function close to high gradients. On the other hand, if the initial control points come from the discretization of a piecewise continuous function, it can be interesting that the subdivision scheme produces a piecewise continuous limit function. For instance, in the approximation of conservation laws, real discontinuities appear as shocks in the solution. The nonlinear modification introduced in this work allows to attain this objective. As far as we know, this is the first subdivision scheme that appears in the literature with these properties

Preliminary characterization of potato virus Y (PVY) populations in Algerian potato fields

To date, only limited data are available concerning the viral pressure present in potato crops in Algeria. For three consecutive years, surveys were conducted in potato fields in the main Algerian potato-growing regions during the mid-season crop cycle (January to March). A total of 285 potato samples were characterized to define the prevalence of the five most common virus species: Potato virus Y (PVY), Potato leaf roll virus (PLRV), Potato virus X (PVX), Potato virus A (PVA) and Potato virus S (PVS). The results showed a higher incidence of PVY compared to the other four viruses. Because of this predominance of PVY and its distribution in all of the scouted regions, an analysis was carried out on the diversity of PVY populations. From a panel of 185 samples, serologically confirmed as being solely infected by PVY, 96.7% were found to be of serotype-N, and only 3.2% of serotype-O. A set of 31 PVY isolates was further analyzed by biotyping on tobacco and by molecular typing (RT-PCR, sequencing), targeting the nucleotide sequence polymorphism in the 5'NTR/P1 region and the three recombination junctions within the HC-Pro/P3 (RJ2), VPg/NIa (RJ3) and CP (RJ4) regions. All 28 PVY isolates from serotype-N inducing vein necrosis on tobacco were recombinant PVYNTN isolates. Among the three PVY isolates of serotype-O, two were typed as PVYN-Wi and induced vein necrosis on tobacco. This is the first report of the identification of NTN and Wilga type isolates in Algeri

Synovitis with pitting edema as the presenting manifestation of antisynthetase syndrome

International audienc