Mathematical Modelling and Simulation of the Behaviour of the Steam Turbine

AbstractModel simulations are becoming very important in dynamic power system analyses. However, no mathematical system can exactly model a physical process. Based on mathematical models of the processes and design calculations, PC programs allow simulation and the determination of the control system performances. This paper presents the mathematical modelling of the steam turbine unit, developed based on the continuity equation. This model is used to determine the simulation diagram for the steam turbine with high, medium and low pressure sections. Using Matlab/Simulink software facilities, have been simulated the behaviour of the shaft torque, depending of the control valves opening, with uncertain parameters of the process, than the step response of the steam turbine, with load and proportional control algorithm

Le remède spéculatif

Le Remède spéculatif. A partir d’une réflexion sur une sentence du moine mystique Angélus Silésius (1624-1679), l’auteur s’emploie à déterminer les caractéristiques principales de l’idée d’un rétablissement de l’âme grâce à la discipline philosophique. En quel sens la philosophie est-elle un remède ? En quel sens la pensée est-elle le seul secours d’un mal dont elle se trouve être, en sa forme immédiate, l’origine ? Telles sont les questions auxquelles cet article s’efforce de répondre.The speculative remedy. This article is a reflection on an epigram of the mystik monk Angelus Silesius (1624-1679), in which the author try to define the main characteristics of the idea of a “soul restore”, thanks to the tradition of the philosophical discipline. In what sense thought may be the cure of an “illness” that is originally determined by thought, in its immediate form? In what sense philosophy may be a speculative remedy?  Das spekulative Heilmittel. Ab einer Überlegung über ein Urteil des mystischen Mönches Silésius-Angelus (1624-1679), verwendet sich der Autor dafür, die Haupteigenschaften der Idee einer Wiederherstellung der Seele dank der philosophischen Disziplin zu bestimmen. In welchem Sinn ist die Philosophie ein Heilmittel ? In welchem Sinn ist der Gedanke die einzige Hilfe eines Übels, dank der sie sich existieren fûhlt in ihrer unmittelbaren Form des Ursprungs ? Dies sind die Fragen, worauf dieser Artikel sich bemüht, zu antworten

Diffusion, réception de l’œuvre d’un artisan-entrepreneur du XIXe siècle : l’atelier Monduit

L’atelier de plomberie et de cuivrerie d’art Monduit fut, durant la seconde partie du XIXe et le début du XXe siècle, l’un des plus éminents représentants de la diversification progressive des activités des artisans et des industriels de l’époque. Essentiellement connue pour sa participation aux restaurations de monuments historiques, la fabrication d’ornements d’architecture et de statues monumentales prestigieuses, l’entreprise Monduit prit également une part active à l’amélioration des infrastructures urbaines et à la création de luminaires. Annuaires, revues techniques, presse savante et populaire aident à apprécier l’étendue des savoir-faire de cet atelier, son rôle social ainsi que la place emblématique qu’il acquit au fil des décennies sur la scène artistique nationale. L’installation de réseaux de canalisation d’eau, la fabrication d’appareils d’éclairage, témoignent, entre autre activités, de l’étendue des réalisations de l’entreprise ; cette assise industrielle lui permit de poursuivre la fabrication d’œuvres remarquables reconnues des architectes, des sculpteurs et d’un public cultivé et de porter à un degré d’excellence peu égalé sa maîtrise du métal au service de l’art.Getting depressed, Jean-Louis Pascal spends a sad end of life. His leaving of the National Library, in 1912, is difficult, even he is succeeded by Ernest Recoura, one of his favorite students he chose to fill his place. He is still passionate about his role as a workshop leader he used to be since 1872 ; his charisma and his students success for winning the Grand Prix de Rome attract many foreign students, coming from America, Switzerland and Austria, and eager to attend his tuitions. At the beginning of the new century, he takes part in the creation of the regional school of architecture and becomes important in the architectural debate, as he used to do throughout his all life writing many papers published in the specialist press, which shows real writing skills. Pascal considered the buildings uniformity, due to the works carried out by the Préfet Haussmann, as “disgusting”. As Charles Garnier did, he stands against styles internationalization and claims for an architecture using local materials, respecting the climate and the regional habits. He will give a proof of this requirement at the early XXth century, for a mansion he designed for a Franco-American couple : the castle of the Doux he considered as one of his most brilliant realisations.Das Blei- und Kupferatelier Monduit spielte im ausgehenden 19. Jahrhundert und zu Beginn des 20. Jahrhunderts eine herausragende Rolle bei der schrittweisen Auffächerung der Tätigkeitsgebiete von Kunsthandwerk und Industrie. Das insbesondere für seine Beteiligung an Restaurierungsmaßnahmen im Bereich der Denkmalpflege bekannte Unternehmen, das architektonische Ornamente und aufwendig gearbeitete Statuen herstellte, war darüber hinaus entscheidend an der Verbesserung städtischer Infrastruktur beteiligt sowie an der Errichtung von Straßenbeleuchtungen. Über Berichterstattung in der Presse und in wissenschaftlichen Zeitschriften fand das Werk des Ateliers breite Aufmerksamkeit und Bekanntheit, was entscheidend zur Festigung der jahrzehntelangen Ausnahmestellung der Maison Monduit im französischen Kunsthandwerk beigetragen hat. Unter anderem zeugen Kanalisationssysteme und Beleuchtungsapparaturen vom breiten Aktivitätsspektrum des Unternehmens; seine Verankerung in der Industrie erlaubt es ihm, auch seine künstlerische Produktion fortzuführen und zahlreiche, von Architekten, Bildhauern und der Öffentlichkeit hochgeschätzte Werke anzufertigen, die Monduits herausragenden Beherrschung der Metallverarbeitung verdeutlichen

Model Reference Adaptive Control Design for Slow Processes. A Case Study on Level Process Control

AbstractThe design of controllers, using conventional techniques, for plants with nonlinear dynamics or model uncertainties can be often quite difficult. Model reference adaptive control (MRAC) is a modern alternative for classic control algorithms and a convenient method to updating the controller's parameters for slow processes with parameter variations. In this paper is presented a comparative study of two design procedures of MRAC for first order slow processes, particularly applied and tested on level process control. The first method it is based on the MIT rule and the second one it is based on the stability theory of Lyapunov. The theoretical results are obtained using Matlab simulation environment

Modeling and Simulation of the Operation of a Mechanical System which is Affected by Uncertainties

AbstractIn control engineering, the mathematical model of the studied process plays an important part. In representing the mathematical model, the inherent errors due to parameter variations define the parametric (structured) uncertainties; therefore there are differences between the mathematical model used in the design process and the real plant. In most cases, the control system needs to stabilize the process and also needs to assure certain performances even in the presence of uncertainties, unmodeled dynamics, disturbance signals and measurement noise, which all make the process vulnerable.This paper shows a method for behavioral modeling and simulation of a gear system, in which the moment of inertia and the friction coefficient represent the parameters which are affected by uncertainties, and are expressed by percentages to the nominal values. For the modeled process, by considering a classical controller, which is tuned experimentally, Matlab is used to represent the sensitivity functions in both time and frequency domains for the nominal cases, for randomly generated samples and for the worst case scenarios

Purpose and criteria for blood smear scan, blood smear examination, and blood smear review.

A microscopic examination of an appropriately prepared and well-stained blood smear by a knowledgeable laboratory professional is necessary and clinically useful in a number of circumstances and for a variety of reasons. In this article, an attempt is made to delineate the purpose and criteria for blood smear examination in a variety of circumstances that are encountered in everyday laboratory hematology practice. A blood smear scan serves to at least (a) verify the flagged automated hematology results and (b) determine if a manual differential leukocyte count needs to be performed. Blood smear examination/manual differential leukocyte count with complete blood count (CBC) provides the complete hematologic picture of the case, at least from the morphologic standpoint. Blood smear review with or without interpretation serves to ensure that no clinically significant finding is missed, besides providing diagnosis or diagnostic clue(s), particularly if and when interpreted by a physician

Is Hemoglobin Variant Analysis Helpful in the Diagnostic Work-up of Patients Revealing Microcytic Erythrocytosis on Complete Blood Count?

Introduction: Microcytic erythrocytosis is an abnormal CBC (complete blood count) finding that is under-recognized, poorly understood, and consequently under-utilized in patient care. It is characterized by decreased MCV and increased RBC count. Its etiology is likely multifactorial and includes thalassemias and hemoglobinopathies. The focus of our study was to determine the relative prevalence of hemoglobin-associated disorders in patients revealing microcytic erythrocytosis on CBC and to demonstrate whether or not hemoglobin variant analysis should be included in the diagnostic work-up of such cases

A virtual reality game for cognitive impairment screening in the elderly: a user perspective

Today, there are 50 million people who have dementia worldwide, that is a new case every3 seconds and more than 152 million cases expected in 2050. Aging-related morbidity is a real social problem making screening a significant challenge. Early diagnosis and management would improve the quality of life offered to the patient and those around him and reduce the economic and social consequences of dementia. The traditional paper-and-pencil approach does not sufficiently reflect the daily reality of the person and what they can accomplish. So, we designed our own VR environment as a candidate solution to the problem

Vocal repertoires and insights into social structure of sperm whales (<i>Physeter macrocephalus</i>) in Mauritius, southwestern Indian Ocean

Sperm whales communicate using codas (stereotyped click sequences). Females and juveniles live in long-term social units, and units with similar coda repertoires share vocal clan membership. Vocal clans exhibit culturally defined differences in their multilevel social structure. Here, we aimed to identify different social units among sperm whales in Mauritius in the southwestern Indian Ocean, and to describe and compare their coda repertoires to investigate the presence of different vocal clans. We conducted six boat-based surveys between 2008 and 2013, during which 101 different individuals were photo-identified. Analysis of associations between 22 resighted individuals divided them into four candidate social units, but a lack of resightings impedes solid delineation of social units. Based on number and rhythm of clicks, at least 24 discrete coda types were detected among 4,767 analyzed codas using two different classification methods. Comparison of coda repertoires recorded from seven sperm whale groupings revealed the possible existence of two sympatric vocal clans, but the size differences of recorded repertoires warrant caution of interpretation. To further evaluate social structuring and the presence of different vocal clans in this region, future surveys should aim at obtaining long-term sighting and acoustic data, and cover a more extensive area