Fabrication and characterisation of U0.85Am0.15O2−x discs for MARIOS irradiation program

This paper describes the developments and results of the fabrication of Am bearing blankets for the MARIOS experiment in the High Flux Reactor (HFR, Petten). This irradiation program aims to asses the influence of the microstructure on the helium release and then fuel swelling for different irradiation temperatures during heterogeneous transmutation mode. In this context, two types of microstructures, dense and tailored porosity, were investigated. The materials were fabricated by a pelletizing-sintering process in the ATALANTE facility. Moreover, dedicated tools were developed to respect the specifications imposed by the program. The results of fabrication indicate that the characteristics of the discs are within the specifications except for open porosity ratio which remains too high for the dense materials.     

Design of self-disinfecting PVC surfaces using the click chemistry

Novel bactericidal PVC surfaces were developed. Cationic copolymers containing alkyne groups and quaternary ammonium or phosphonium groups were successfully synthesized and characterized. These polymers were grafted by click chemistry on PVC surfaces bearing azide groups (PVC-N3). The modified surfaces exhibited higher polarity and hydrophilicity in comparison with non grafted surfaces. Accessible surface charge densities varied from 1.1 × 10¹⁴ to 6.5 × 10¹⁴ charge cm^?2. In these conditions, bactericidal effects of the cationic surfaces against Escherichia coli and Staphylococcus epidermidis were evidenced by the Live and Dead fluorescent assay.     

Dielectric investigation of MM(PO4)2 double orthophosphates (M = Ca, Sr, Ba, Pb; M = Ti, Zr, Hf, Ge, Sn)

M^IIM^IV(PO₄)₂ (M^II = Ca, Sr, Ba, Pb; M^IV = Ti, Zr, Hf, Ge, Sn) ceramics were prepared by solid state reaction method and consolidated by spark plasma sintering in order to study their electrical properties. The dielectric study performed at room temperature was aimed to determine the basic electrical properties of these compounds. Maxwell-Wagner polarization contributions, which are active at low frequencies cause a strong extrinsic increase of both real and imaginary part of permittivity as well of the dc-conductivity for BaZr(PO₄)₂, BaTi(PO₄)₂, BaHf(PO₄)₂, and SrGe(PO₄)₂ double orthophosphates. Moderate real (ε^′r=20-150) and imaginary low-frequency permittivity (ε^′r=7-300) and typical Debye relaxation with relaxation time in the range of ms is typical for: PbHf(PO₄)₂, PbZn(PO₄)₂, and CaGe(PO₄)₂. At high-frequency (f = 10⁹ Hz), the ceramics have permittivities of 2.29÷8.02 and tangent loss of 0.003÷0.153. The compounds SrGe(PO₄)₂, BaGe(PO₄)₂, BaZr(PO₄)₂ and BaSn(PO₄)₂ have excellent high-frequency dielectric characteristics, with losses of 3÷6% and permittivity slightly above 2 and are possible candidate as microwave ceramics.     

Intelligent distributed production control

This editorial introduces the special issue of the Springer journal, Journal of Intelligent Manufacturing, on intelligent distributed production control. This special issue contains selected papers presented at the 13th IFAC Symposium on Information Control Problems in Manufacturing??INCOM??2009 (Bakhtadze and Dolgui 2009). The papers in this special issue were selected because of their high quality and their specific way of addressing the variety of issues dealing with intelligent distributed production control. Previous global discussions about the state of the art in intelligent distributed production control are provided, as well as exploratory guidelines for future research in this area.     

Hybrid modeling and identification of dry friction systems,application to a clutch actuator

This paper proposes a new general framework, i.e. hybrid modeling, to model dry friction systems. The proposed hybrid model has two modes (states): one models the system sliding, the second the system sticking. The model's main advantage is the adaptation capability to observable phenomena. It is shown for the most common behaviors encountered experimentally and comparisons with other models presented in the literature are carried out. The models and methods of parameters identification of the literature are generally validated experimentally on system with sensors and actuators of high precision. This paper focuses on modeling and identifying complex mechanical system with low resolution sensors. The presented theoretical work is validated experimentally on a clutch-by-wire.     

A constraint-based approach for the shift design personnel task scheduling problem with equity

This paper presents an industrial problem which arises in a company specialized in drug evaluation and pharmacology research. The aim is to build employee timetables covering the demand given by a set of fixed tasks. The optimality criterion concerns the equity of the workload sharing. A solution to this problem is the assignment of all tasks whose resulting working shifts respect tasks requirements as well as legal and organizational constraints. Scheduling problems usually consider a fixed set of shifts which have to be assigned to a given number of employees whereas in our problem shifts are not fixed and are deduced from the task assignment. In the following, we refer to this problem as the shift-design personnel task scheduling problem with an equity criterion (SDPTSP-E), in reference to the shift minimization personnel task scheduling problem (SMPTSP). Even if the SDPTSP-E is related to several problems, none of them allow to grasp its full complexity. Consequently, we propose a dedicated method based on constraint programming. Several branching and exploration strategies are proposed and tested.