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This paper explores the designing principles to create resilient Supply Chains ({SC)} with the ability to return, rapidly, to the initial stage or to an improved one after a disturbance occurrence. Supply chain disturbances and failure modes are identified and discussed. The concept of resilience applied to {SCs} is defined and explored; a conceptual {SC} Resilience Index and a {SC} Resilience Indicator are proposed. A framework for the design of resilient supply chains is introduced, identifying main {SC} characteristic that can be modified to increase {SC} resilience and to mitigate its inherent vulnerability. An exploratory simulation study is presented to test the design of alternative {SC} scenarios.

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The emergence of multi-core processors is promoting the use of concurrency and multithreading. To raise the abstraction level of synchronization constructs is fundamental to ease the development of concurrent software, and Software Transactional Memory (STM) is a good approach towards such goal. However, execution environment issues such as the processor instruction set, caching policy, and memory model, may have strong influence upon the reliability of STM engines. This paper addresses the testing of STM engines aiming at improving their reliability and independence from execution environment. From our experience with porting and extending a specific STM engine, we report on some of the bugs found and synthesize some testing patterns that proved to be useful at testing STM engines.

Algebraic theories for modeling components and their interactions offer abstraction over the specifics of component states and interfaces. For example, such theories deal with forms of sequential composition of two components in a manner independent of the type of data stored in the states of the components, and independent of the number and types of methods offered by the interfaces of the combinators. General purpose programming languages do not offer this level of abstraction, which implies that a gap must be bridged when turning component models into implementations. In this paper, we present an approach to prototyping of component-based systems that employs so-called type-level programming (or compile-time computation) to bridge the gap between abstract component models and their type-safe implementation in a functional programming language. We demonstrate our approach using Barbosa's model of components as generalized Mealy machines. For this model, we develop a combinator library in Haskell, which uses type-level programming with two effects. Firstly, wiring between components is computed during compilation. Secondly, the well-formedness of the component compositions is guarded by Haskell's strong type system.

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In the presentwork we have studied the properties of zinc oxide (ZnO) thin films grown by laser ablation of ZnO targets under different substrate temperature and background oxygen conditions. The ZnO layers were deposited with a Pulsed Laser Deposition (PLD) system on pre-nitrided (0001) sapphire (Al2O3), using the base line of a Nd:YAG laser at 1064 nm. The films were characterized by different structural and optical methods, including X-ray diffraction (XRD), scanning electron microscopy (SEM), optical transmission spectroscopy, and steady-state photoluminescence (PL). XRD analysis with rocking curves and $þeta$–2$þeta$ scans indicates preferential growth along the c-axis direction with a full width at half maximum (FWHM) smaller than 1.5◦. Low-temperature photoluminescence (PL) showed strong excitonic emission near 3.36 eV between 9 and 65 K