Interpreting process data of wet pressing process: Part 1: Theoretical approach

The wet pressing process represents a new production method for carbon fibre-reinforced plastics components. Due to the low cycle times, it is suitable for use in the automotive industry. Therefore, a sufficient degree of industrialisation needs to be achieved, which is characterised by a stable process. The knowledge about relevant process parameters, their interactions, and influence on the part quality builds the basis of an economic process. This is a major challenge, since in the early stage of process development the available amount of recorded process data is small and the data sets are not complete. As the implementation of time-, material-, and cost-intensive experiments represents no acceptable alternative, a theoretical approach is chosen. This article describes a theoretical procedure to define the critical factors of the wet pressing process with significantly less resource input

Approach to a process integrated quality control system for non stable processes

As production processes become more complex it is necessary to gain knowledge about the causalities between input and output parameters. Additionally an in-time problem solving is essential for a quality oriented production. These accounts require the implementation of a process integrated quality control system. The goals are the recognition of the causalities, inspection of the process’ parameters and taking action in case of irregularities within the process. In addition the quality control system has to be able to act predictively in arranging the following process steps. SPC is a standard tool for statistical process control but requires a stable process. Anyhow tools for quality control are needed which base on non stable processes. The following dissertation describes an approach for a quality control system in a non stable process environment. The example is a casting process in a light metal foundry. The developed quality control system is made up of two contrarily directed quality control loops. A reactive quality control loop is used for determination of the causalities and for taking action for optimizing the production process. In addition a predictive quality control loop is implemented which initiates the following activities in the process chain. The necessary inspection efforts for the parts’ delivery are included in the predictive loop. The essential part of both quality control loops are the analytical methods for model building. As appropriate tools Data Mining methods have been established. The methodical analytic approach has been approved on several analyses in the BMW light metal foundry and fully been integrated into the problem solving process. The following approach is applied: Learning from the past for designing the present to improve the future.Für die umfassende qualitätsorientierte Serienfertigung sind bei den immer komplexer werdenden Fertigungsprozessen die Kenntnis über die Kausalzusammenhänge zwischen Eingangs- und Zielgrößen sowie die rechtzeitige gezielte Fehlerbeseitigung notwendig. Aus diesem Grund wird ein prozessintegriertes Qualitätsregelungssystem benötigt, innerhalb dessen die Kausalzusammenhänge transparent aufgezeigt, die einzelnen Prozessparameter überwacht und bei Verlassen der vorgegebenen Grenzen auch Maßnahmen abgeleitet werden. Zusätzlich dazu soll das Qualitätsregelungssystem aber auch in der Lage sein, die Prozessschritte dynamisch gestalten zu können, um präventiv in den Prozess einzugreifen. Für die Regelung statistisch beherrschter Prozesse sind Verfahren wie zum Beispiel die SPC (Statistical Process Control) Standard, setzten aber immer einen fähigen und beherrschten Prozess voraus. Trotzdem werden auch für nicht fähige und nicht beherrschte Prozesse, die so genannten nicht stabilen Prozesse, Verfahren zur Prozessregelung benötigt. Die vorliegende Arbeit beschreibt einen Ansatz für ein Qualitätsregelungssystem am Beispiel eines nicht stabilen Fertigungsprozesses in einer Leichtmetallgießerei. Für den Aufbau des Qualitätsregelungssystems wird eine Verkettung zweier unterschiedlich gerichteter Qualitätsregelkreise eingesetzt. Ein reaktiver Qualitätsregelkreis dient der Bestimmung der Kausalzusammenhänge innerhalb des Produktionsvorganges und der Ableitung von Maßnahmen zur Produktionsoptimierung. Zusätzlich dazu wird ein präventiver Qualitätsregelkreis implementiert, in dem Anpassungsmaßnahmen für die weitere Steuerung des Prozesses inklusive der zur Auslieferungsfreigabe notwendigen Bauteilprüfungen initiiert werden. Kernbestandteil beider Qualitätsregelkreise sind analytische Verfahren zur Modellbildung aus dem Bereich des Data Minings. Für den Einsatz sind unterschiedliche Verfahren diskutiert und ausgewählt worden. Am Beispiel mehrerer Untersuchungen in der Leichtmetallgießerei von BMW ist der methodische datengetriebene Ansatz bestätigt und mittlerweile fest in den Problemlösungsprozess integriert worden. Es gilt folgender Ansatz: Von der Vergangenheit lernen, die Gegenwart zu gestalten, um die Zukunft zu verbessern

Interpreting process data of wet pressing process: Part 2: Verification with real values

For the analysis of the wet pressing process, which was presented in the first part of this paper, a theoretical approach was chosen. This enabled the pre-definition of three quality-related priorities which now will be considered in detail in the second part. For further analysis, real process data, recorded in an early phase of the process implementation, are used. The challenge is that in this process status, the availability of data is limited or the data sets are incomplete. Supported by the theoretical approach, an easier interpretation of the process data, and in case of ambiguous issues, an accelerated decision making is expected. The objective is to show that this combination is suitable for the process analysis in an early production phase

Chlororespiration and Grana Hyperstacking: How an Arabidopsis Double Mutant Can Survive Despite Defects in Starch Biosynthesis and Daily Carbon Export from Chloroplasts1[W]

An Arabidopsis (Arabidopsis thaliana) double mutant impaired in starch biosynthesis and the triose phosphate/phosphate translocator (adg1-1/tpt-1) is characterized by a diminished utilization of photoassimilates and the concomitant consumption of reducing power and energy produced in the photosynthetic light reaction. In order to guarantee survival, the double mutant responds to this metabolic challenge with growth retardation, an 80% decline in photosynthetic electron transport, diminished chlorophyll contents, an enhanced reduction state of plastoquinone in the dark (up to 50%), a perturbation of the redox poise in leaves (increased NADPH/NADP ratios and decreased ascorbate/dehydroascorbate ratios), hyperstacking of grana thylakoids, and an increased number of plastoglobules. Enhanced oxygen consumption and applications of inhibitors of alternative mitochondrial and chloroplast oxidases (AOX and PTOX) suggest that chlororespiration as well as mitochondrial respiration are involved in the enhanced plastoquinone reduction state in the dark. Transcript amounts of PTOX and AOX were diminished and nucleus-encoded components related to plastidic NADH reductase (NDH1) were increased in adg1-1/tpt-1 compared with the wild type. Cytochrome b559, proposed to be involved in the reoxidation of photosystem II, was not regulated at the transcriptional level. The hyperstacking of grana thylakoids mimics adaptation to low light, and increased plastoglobule numbers suggest a response to enhanced oxidative stress. Altered chloroplast organization combined with perturbations in the redox poise suggests that adg1-1/tpt-1 could be a tool for the in vivo study of retrograde signaling mechanisms controlling the coordinated expression of nucleus- and plastome-encoded photosynthetic genes

REVE DE VALSE / OSCAR STRAUS ; ANDRE DASSARY

Titre uniforme : [Ein Walzertraum]. ChoixBnF-Partenariats, Collection sonore - BelieveContient une table des matière

REVE DE VALSE - Extraits / Oscar STRAUS - Livret de DORMANN et JACOBSON - adaptation française de Léon XANROF et Jules CHANCEL ; André DASSARY (Fonségur) - Lina DACHARY (Hélène) - Colette MUZART (Franzi) - Guy GODIN (Moussy) - Fréda BETTI (Frédérique) - Serge CLIN (Lothar) avec Orchestre et Choeurs dir. Hans KILLER - Dir. artistique : Guy DUMAZERT

Titre uniforme : [Ein Walzertraum]. ChoixComprend : Ouverture - Mesdam's, Messieurs, j'ai de l'émoi (Fonségur) - Jamais, je ne fus plus heureuse (Hélène - Frédérique) - Oui, c'est une valse de Vienne (Fonségur - Moussy) - Si j't'escorte le soir... - C'est nous les p'tit's musiciennes - Voyons, puisque la destinée (Franzi et Fonségur) - Moi, de la flûte, j'ai le don (Franzi-Lothar) - Amour printanier - Ah ! si j'étais artiste (Franzi-Frédérique) - Finale : "Rêve de valse, rêve d'un jour"BnF-Partenariats, Collection sonore - BelieveContient une table des matière