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This research exposes a new methodology to follow the evolution of polymer crystallinity during material extrusion thanks to the use of thermocouples and fast scanning calorimetry (FSC). Micrometric thermocouples allowed recording the thermal history at different locations on a polypropylene (PP) part, which was then used to reproduce the thermal process conditions in FSC. This method allows to precisely study the evolution of PP crystallinity as function of time, which is an important feature to predict the printability of polymers, since crystallization is known to restrain fusion between beads. The results highlighted the dependence of the periodic thermal stress undergone by PP on several characteristics (e.g.layer surface area, location in the part, filling strategy). Therefore, the crystallization behavior was found to be different depending on the location in the part. Crystallization was delayed at the center of the part compared to the edges because the nozzle sweep frequency was higher at the center, resulting in lower cooling kinetics.

This paper summarizes the discussions held during an in-depth six-hour workshop on the challenges of combining data from different survey modes with the anticipated aim of identifying current research needs. The main theme of the workshop was mixing survey modes as a way to meet the challenge of low response rates. However, the use of multi-mode surveys introduces new sources of bias: not all households have access to certain survey media (coverage bias); the response rate using one or another of the survey modes is correlated with social demographics (non-response bias); the sampling frame is dependent on the mode (sampling bias) or the instrument itself may affect the responses (measurement bias). The aim of this report is present the workshop's discussion on the identification of research needs with related to combining data from different survey modes.

We present the results of a web survey presented to non-respondents of a main telephone survey and compare declared mobility of both survey modes. After a description of the population who answered online, we summarise travel patterns and estimate a selection bias. Results are consistent with the hypothesis of an under declaration attributable to the web, as far as we know, that the risk of omitting trips concerns especially short trips and less constrained trip purposes. From comparison with a previous face-to-face and web survey we give some perspectives for future household travel surveys.

This article focuses on the design of reliable control system instrumentation. It describes a design methodology using structural modeling. This method provides instrumentation structural links from graphical tree representation, and this graphical tool allows obtaining different paths for accessing the physical quantities concerning the fixed mission by the designer for the control system. The main of our contribution is to assess the reliability thanks to structural links of control system during design phase. The mission of the speed control of electric vehicle is used as an illustrative example.

The unlimited proliferation capacity of embryonic stem cells (ESCs) combined with their pluripotent differentiation potential in various lineages raised great interest in both the scientific community and the public at large with hope for future prospects of regenerative medicine. However, since ESCs are derived from human embryos, their use is associated with significant ethical issues preventing broad studies and therapeutic applications. To get around this bottleneck, Takahashi and Yamanaka have recently achieved the conversion of adult somatic cells into ES-like cells via the forced expression of four transcription factors: Oct3/4, Sox2, Klf4 and c-Myc. This first demonstration attracted public attention and opened a new field of stem cells research with both cognitive – such as disease modeling - and therapeutic prospects. This pioneer work just received the 2012 Nobel Prize in Physiology or Medicine. Many methods have been reported since 2006, for the generation of induced pluripotent stem (iPS) cells. Most strategies currently under use are based on gene delivery via gamma-retroviral or lentiviral vectors; some experiments have also been successful using plasmids or transposons- based systems and few with adenovirus. However, most experiments involve integration in the host cell genome with an identified risk for insertional mutagenesis and oncogenic transformation. To circumvent such risks which are deemed incompatible with therapeutic prospects, significant progress has been made with transgene-free reprogramming methods based on e.g.: sendai virus or direct mRNA or protein delivery to achieve conversion of adult cells into iPS. In this review we aim to cover current knowledge relating to both delivery systems and combinations of inducing factors including chemicals which are used to generate human iPS cells. Finally, genetic instability resulting from the reprogramming process is also being considered as a safety bottleneck for future clinical translation and stem cell-therapy prospects based on iPS.

ABSTRACTBloom syndrome (BS) is a rare human autosomal recessive disorder characterized by marked genetic instability associated with greatly increased predisposition to a wide range of cancers affecting the general population. BS arises through mutations in both copies of the BLM gene which encodes a 3’-5’ DNA helicase identified as a member of the RecQ family. Several studies support a major role for BLM in the cellular response to DNA damage and stalled replication forks. However, the specific function(s) of BLM remain(s) unclear. The BLM protein is strongly expressed and phosphorylated during mitosis, but very little information is available about the origin and the significance of this phosphorylation. We show here that ATM kinase provides only a limited contribution to the mitotic phosphorylation of BLM. We also demonstrate that BLM is directly phosphorylated at multiple sites in vitro by the mitotic cdc2 kinase, and identify two new sites of mitotic BLM phosphorylation: Ser-714 and Thr-766. Our results identify BLM helicase as a new substrate for cdc2, which may have potential physiological implications for the role of BLM in mitosis.

Statistical control of quality provides a useful example of the way in which industry practices a pragmatic-scientific approach for managing production operations. Knowledge, applied to action, has circumscribed theories with means-end constraints, feedback deadlines, and information economies. These have, surprisingly, led to further original and fruitful theoretical questions. Moreover, the need to adapt scientific methods to a little-qualified workforce produced innovative cognitive tools. This paper studies these aspects of the knowledge-creation process in an industrial activity and shows that the metaphor of a ‘dialogue’ organized between facts and theory is, in this context, more accurate than the model of hypothesis testing and planned experiment.

An operator $T$ on a Banach space $X$ is said to be weakly supercyclic (respectively $N$-supercyclic) if there exists a one-dimensional (respectively $N$-dimensional) subspace of $X$ whose orbit under $T$ is weakly dense (respectively norm dense) in $X$. We show that a weakly supercyclic hyponormal operator is necessarily a multiple of a unitary operator, and we give an example of a weakly supercyclic unitary operator. On the other hand, we show that hyponormal operators are never $N$-supercyclic. Finally, we characterize $N$-supercyclic weighted shifts.

We investigate the radial behavior of holomorphic functions in the unit ball $B$ of $\mtc^n$. In particular, we prove the existence of universal holomorphic functions $f$ in the following sense : given any measurable function $\vphi$ on $\partial B$, there is a sequence $(r_n)_{n\geq 1}$, $0r_n1$, that converges to 1, such that $f(r_n\xi)$ converges to $\vphi(\xi)$ for almost every $\xi\,{\in}\,\partial B$.

In this paper, we propose a cheap stereovision sensor. It is made of two Webcams based on low cost CMOS technology imaging sensors. Computation and images' acquisitions are performed by a standard Computer (PC). We first focus on the advantages of such a system on CCD-based technologies, and then we explain how the tri-dimensional measurements can be obtained. Before concluding, we give some experimental results expressing the effectiveness of the approach

This paper deals with control system design and optimisation according to a cost criterion and dependability constraints related to the number of tolerated faults. The proposed method is designed to be used with a system model that describes both functional and dysfunctional behaviour and takes the different hardware architecture options into consideration. This model is derived through a functional decomposition of the system, completed by dependability data.

In this paper we study a discrete Raman laser amplification model given as a Lotka-Volterra system. We show that in an ideal situation, the equations can be written as a Poisson system with boundary conditions using a global change of coordinates. We address the questions of existence and uniqueness of a solution. We deduce numerical schemes for the approximation of the solution that have good stability.

Designing an automation control system does not consist only in establishing an organisation of components that performs a specified task. Indeed, with an industrial point of view, the objectives are to find a system, which has a good dependability with a low cost. Dependability is a significant factor, because it qualifies the way of performing the specified task. Therefore, the two aspects, cost and dependability, have to be simultaneously studied early in design.

Smart devices used in continuous system, benefit from the addition of microelectronics and software that runs inside the device to perform control and diagnostic functions. Very small components, such as inputs/outputs blocks and overload relays, are too small to integrate data processing for technical-economic reason. However, it's possible to develop embedded intelligence and control for the smallest factory floor devices. In the paper, a generic model of smart equipment with reconfiguration functions is proposed. The interest of this functional model is that it can be used for smart devices but it can also be developed in modules for the nearest possible of the inputs and outputs in manufacturing equipment. This solution is economic for a great number of applications because it allows one to realise modular design and to standardise part of system in order to re-use it.

Dans le domaine de la conception des structures ae´ronautiques, une proble´matique re´cente concerne l'ame´lioration du comportement me´canique des structures lors de crashs dit « survivables ». Deux approches du proble`me peuvent e^tre envisage´es. La premie`re, expe´rimentale, repose sur l'utilisation de maquettes de crash a`e´chelle 1 ou re´duite. La seconde, nume´rique, consiste a` utiliser des outils de calcul. Malgre´ leurs nombreux avantages (e.g. le cou^t, la possibilite´ de proce´der a` des simulations parame´triques), ces outils pre´sentent encore des limites lie´es principalement a` la repre´sentativite´ des non line´arite´s mate´rielles et ge´ome´triques, et a` la sensibilite´ des re´sultats a` la finesse de maillage. De ce point de vue, une des difficulte´s majeures concerne encore la mode´lisation de la localisation des de´formations plastiques et de l'endommagement dans les to^les, pre`s des perforations ne´cessaires a` la mise en place des rivets. Cette localisation me`ne a` une fragilisation des structures qui pilote la ruine. Les notions de fragilisation structurale et de mesure de la fragilisation sont tout d'abord introduites par l'interme´diaire d'une e´tude analytique dans les domaines de l'e´lasticite´ et de la plasticite´ confine´e. Une caracte´risation de la mesure de la fragilisation est entreprise de fac¸on expe´rimentale et nume´rique afin de pallier les limites des me´thodes analytiques dans le domaine des grandes de´formations. Enfin, un mode`le phe´nome´nologique de la fragilisation structurale, pre´curseur du de´veloppement d'un e´le´ment de coque fragilise´, est pre´sente´ et discute´.

The first part of the paper deals with the assessment of several methods using Lagrangian and Arbitrary Lagrangian Eulerian (ALE) formulations in Radioss to model bird impacts onto rigid panels. FE results are compared with experiments in terms of local pressure, including Hugoniot and Stagnation ones, and global load. Two methodologies are chosen: one using a Lagrangian method and an hydrodynamic viscous model for the bird, and another using ALE method and an hydrodynamic bi-phase liquid/gas medium for the air and bird model. With the Lagrangian method, results are in a good agreement compared with available experimental results but the computing cost is expensive. With the ALE method, the calculation cost is lower. The second part of the paper deals with bird impact modelling onto metallic riveted panels using both FE methods. Results are in a good agreement with experiment when the metallic panel IS dented only. For bird penetration cases. results highlight the problem of the modelling of the structural embrittlement due to the riveted joints (structural failure comes from a crack propagation between rivets).

In this paper, we propose a formal description of a component, which has been established, with objectives of system evaluation. After a short introduction to the concept of component, its external model, integrating notions of services, versions and modes, are recalled to formalise the component description. Finally, a synchronous language is used to compute the formal description, what which allows to evaluate the component. Such description can be applied to smart equipment considered alone, but also to component of global architecture

The development of smart sensors and actuators associated to the communication facilities offered by fieldbuses allow distributing data processing in automation systems. However for the sensors (or actuators) manufacturers, the design of intelligent devices is quite difficult according to the variety of fieldbuses, and the needs of flexibility and standardisation. In that sense, a development tool for design smart devices has been conceived. This tool allows easily realising the soft of an application, which would be implemented in a microcontroller in order to obtain smart devices. The IEC 1131-3 norm is used to describe the functions, and a C program is automatically generated.

Design of an automation system does not consist only in establishing an architecture of components with the lower cost. Indeed, with an industrial point of view, dependability is a significant factor. Untimely stops, incidents occurrences or the unavailability of the control system have important economical consequences. Therefore, these two aspects (cost and dependability) have to be studied simultaneously. This paper presents a methodology to design an automation system (or eventually to improve an existent system), which takes into account these two aspects. From a functional model, the method aims to detennine the operational architecture that respects a set of constraints relative to the dependability with the lower cost. One advantage of the presented method is that it can be used despite a lack of data concerning the reliability of components. The dependability is considered with a semiqualitative point of view and consists in defining some limits in terms of number of failure components, which don't entail the failure or the unavailability of the system.

In the paper, a formal method using SyncCharts is presented. It allows to validate some functionalities of smart equipment modelized by external model. This one includes notion of services and user operating modes. Functional and behavioral validations can be obtained during design before realization step.

This paper presents the design of an architecture automation system obtained by the interconnection of elementary smart instruments. An approach of design of such architecture is based on the concept of external model. It permits to designers to analyse the fault tolerance aspects.

The distribution of the intelligence among all the components of the automation system allows to consider them as a connexion of a number of intelligent objects which produce or consume informations via a communication system associated with global management rules.

This paper presents the generic functional architecture of a smart actuator. It mainly addresses the decomposition level relative to Fault Diagnosis and Isolation and details the mode management module.

The increasing complexity of control systems, as well as the large dimensions of the controlled processes, lead to the development of distributed control. New control architectures are mainly based on communication and on intelligent instrumentation concepts.

In this paper, the generic model developed for smart instruments and the synchronous model SYNCCHARTS are used to specify automated systems. The generic model provides us with an external description, which is the user's point of view, and the SYNCCHARTS model gives a behavioral model of the system. For those two models to provide complementary information upon a device, a method is proposed to obtain a coherent syncChart from a part of the external model. The classical example of an automobile speed cruise control system is used for illustration.

The paper sets the problem of the design step in the context of production automated systems and presents a modeling of this activity. The design step is located after the specification one and before the strictly speaking implementation one. The problem is to be sure that the partitioning of the specified application into intercommunicating modules and the allocation of the modules to computing assets and communication systems will satisfy the different constraints expressed in the end-user requirements, and in the specification.

In the paper, we formulate the distribution problem as a clustering one and we propose a method based on a mixed hierarchical clustering algorithm which associates the merge and split hierarchical clustering operators. The merge operator aggregates the two classes whose data flow exchange cost is maximum while the split one separates one class into two optimal sub-classes. We show that the mixed algorithm converges towards a local optimal solution in the set of the partitions of the RTPOS into k classes.

The development of “Intelligent Distributed Automation Systems” requires the use of models which allow to structure specifications by providing the designer with means to justify his technological choices and to verify that the proposed hardware architecture will allow to answer the stated needs. Generally, communication function is studied independently of instruments. However, a global approach seems to be necessary. That is the reason why we propose to use the same model to study smart instruments and communication. In the paper, we apply the external model defined for sensors and actuators to communication systems. We show by application to two fieldbuses (WorldFip and Profibus) that the obtained model is a generic one.

In this paper, the generic model, we have developped for smart instruments, is used to specify hybrid systems. The proposed model contains on one hand an external description which is the user’s point of view, and on the other hand, the internal description which provides the functionalities which have to be implemented. In particular, we focuse our interest on operating modes and we compare our description with other specifications of reactive systems such as Statecharts. The classical exemple of an automobile cruise control system is used for illustration.

In the paper, we describe a prototype of smart on/off valve which makes use of the external model. The hardware architecture is based on a micro controller 980552B from Philips. The software developed on the laboratory is implemented from function blocks created using the IEС 1131-3 Norm which allows to describe automation system.

The paper presents the smart instrument generic description organized around User Operating Mode management. In order to build smart instruments based distributed architectures which include several components, we propose an ascendant method to build the User Operating Mode of a set of devices. An example, including a smart sensor and a smart actuator, illustrates our approach.

The proposed paper presents the application of a model based FDI method to the supervision of an asynchronous drive. The obtained results allow to define local essential instrumentation for its advanced control and supervision.

This paper deals with different issues related to the spectral behavior of erbium-doped fiber amplifiers within multichannel systems. The requirements fiber amplifiers will have to meet for implementation in future all-optical transport networks are discussed. The current status of various attempts to flatten the nonuniform gain bandwidth of conventional silica-based amplifiers and the limitations they induce in multichannel systems is reviewed as well. The improvements in gain flatness offered by fluoride-based fiber amplifiers are theoretically and experimentally investigated and highlighted in various multichannel system experiments. From this study, fluoride-based amplifiers appear to be an effective solution of high potential for significantly increasing the available bandwidth in transport networks of high capacity and flexibility. Copyright 1995, 1999 Academic Press

The paper presents the functions of intelligent instruments in the frame of Real Time Process Operating Systems and shows that they have the same functional structure as the system itself. Thus, smart instruments based distributed architectures can be built provided they present interoperability properties. Some working groups and projects whose aim is to define interoperable field instruments are presented. In the last part, the paper proposes a smart instrument generic description.