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A lack of consistent data, reliable analysis techniques, and user-friendly tools is inhibiting decision makers' abilities to assess and evaluate the sustainability performance of manufacturing processes and systems. Recent integration of information technology with advanced manufacturing technologies has led to a new paradigm, termed smart manufacturing or Industry 4.0. To leverage this paradigm shift for the advancement of sustainable manufacturing, efforts have been made to characterize unit manufacturing processes (UMPs) for sustainability assessment and to develop frameworks, methodologies, and standards utilizing information modeling approaches. This paper proposes a grey box object-oriented software framework for sustainability assessment of complex manufacturing systems, utilizing the multiple inheritance principle for composition of UMP models. Information modeling guidelines based on the framework are provided for UMP model developers and UMP performance analysts to construct and analyze system models. To demonstrate the usefulness of the framework and guidelines, a prototype information model is developed for a hybrid manufacturing system composed of fused deposition modeling (an additive process) and CNC milling (a subtractive process). [ABSTRACT FROM AUTHOR]

In this paper a passive integrator dedicated to input/output Hamiltonian systems approximation is presented. In a first step, a discrete Hamiltonian framework endowed with a Lie derivative-like formula is introduced. It is shown that the discrete dynamics encodes energy conservation and passivity. Additionally, the characterization of the discrete dynamics in terms of Dirac structure is shown to be invariant by interconnection. The class is thus composable: networked systems belong to the class. In a second step, the discrete dynamics is considered as a one-step integration method. The method is shown to be convergent and provides a discrete-time approximation of an input/output Hamiltonian system. Accordingly, the discrete dynamics inherits intrinsic energetic characteristics (storage function and dissipation rate) from the original system. The method is thus tagged as passive integrator. As an illustration, the closed-loop behavior of interconnected subsystems and the stabilization of a rigid body spinning around its center of mass are presented. [ABSTRACT FROM AUTHOR]

Efficiency of natural stone production processes in quarries directly affects the economic output and environmental performances, such as production lead times and energy consumptions. Knowledge on stone production processes is crucial in making responsible decisions in this business. Having a structured representation of information characterizing the stone production processes will support stakeholders in better assessing production resources in terms of sustainability and productivity. Value stream mapping can provide an overview and guidance for sustainability performance evaluation, but its application is limited. The challenges arise when trying to specifically map and relate sustainability data between processes e.g., variability in lead time and CO 2 emissions. Manufacturing process characterization standards currently being developed by ASTM International manifest the potential to not only fill this gap but also to provide opportunities to characterize and compose manufacturing processes with relevant environmental information and description. This paper shows the application and lessons learned from deploying one such effort towards standardization. [ABSTRACT FROM AUTHOR]

Triple-modular-redundant applications are widely used for fault-tolerant safety–critical computation. They have strict timing requirements for correct operation. We present an architecture which provides composability and mixed-criticality to support integration and to ease certification of such safety–critical applications. In this architecture, an additional layer is required for the sharing/partitioning of resources. This potentially jeopardizes the synchronization necessary for the triple-modular-redundant applications. We investigate the effects of different (unsynchronized) scheduling methods for the resource-sharing layer in this architecture and conclude that an out-of-the-box solution, which guarantees the technical separation between applications with fast reaction time requirements is only feasible when executing at most one instance of a triple-modular-redundant application per CPU-core for single and multi-core CPUs. Only when accepting changes in the applications or the applications’ synchronization mechanisms, are more flexible solutions with good performance and resource utilization available. [ABSTRACT FROM AUTHOR]

Abstract: The European ARTEMIS ACROSS project aims to overcome the limitations of existing Multi-Processor Systems-on-a-Chip (MPSoC) architectures with respect to safety–critical applications. MPSoCs have a tremendous potential in the domain of embedded systems considering their enormous computational capacity and energy efficiency. However, the currently existing MPSoC architectures have significant limitations with respect to safety–critical applications. These limitations include difficulties in the certification process due to the high complexity of MPSoCs, the lacking temporal determinism and problems related to error propagation between subsystems. These limitations become even more severe, when subsystems of different criticality levels have to be integrated on the same computational platform. Examples of such mixed-criticality integration are found in the avionics and automotive industry with their desire to integrate safety–critical, mission critical and non-critical subsystems on the same platform in order to minimize size, weight, power and cost. The main objective of ACROSS is to develop a new generation of multi-core processors designed specially for safety–critical embedded systems; the ACROSS MPSoC. In this paper we will show how the ACROSS MPSoC overcomes the limitations of existing MPSoC architectures in order to make the multi-core technology available to the safety–critical domain. The proposed approach enables efficient certification, complexity management, mixed-criticality integration and the development of temporally deterministic hard real-time systems. The major technological innovations of ACROSS are an increased level of design abstraction, message-based interfaces for core-to-core communication and reliable fault and error containment established by a novel time-triggered network-on-chip. The achieved results comprise, a novel architecture for MPSoCs, a prototype implemenation on FPGA technology as a proof-of-concept, a comprehensive set of middle-ware services and multiple demonstrators that show the benefits of the ACROSS Architecture in real world industrial applications. [Copyright &y& Elsevier]

Abstract: Viewpoint modeling is an effective approach for analyzing and designing complex systems. Splitting various elements and corresponding constraints into different perspectives of interests, enables separation of concerns such as domains of expertise, levels of abstraction, and stages in lifecycle. Specifically, in Systems Engineering different viewpoints could include functional requirements, physical architecture, safety, geometry, timing, scenarios, etc. Despite partial interdependences, the models are usually developed independently by different parties, using different tools and languages. However, the essence of Systems Engineering requires repetitive integration of many viewpoints in order to find feasible designs and to make good architectural decisions, e.g., in each mapping between consecutive levels of abstraction and in each design space exploration. This integration into one consistent model becomes a significant challenge from both modeling and information management perspectives. In this paper we suggest (1) a unique modular algebraic viewpoint representation robust to design evolution and suitable for generation of the integrated optimization/analysis models, and (2) an underlying ontology-based approach for consistent integration of local viewpoint concepts into the unified design space model. We show an example of an optimization model with different combinations of partially interdependent Analysis Viewpoints. Using the proposed modeling and information management approaches the underlying viewpoint''s equations can be applied without modification, making the approach pluggable. [Copyright &y& Elsevier]

• Novel high molecular weight 100% bio-based random aliphatic-aromatic copolymers of PTF containing different amounts of sebacic acid were synthesized by eco-friendly polycondensation in the melt. • Low amounts of PTSeb comonomeric units significantly modify PTF thermal, mechanical and barrier properties and render the final material compostable. • PTF15PTSeb copolyester exhibited superior gas barrier properties to O 2 and CO 2 , and temperature induced shape memory behavior, which foreshadows possible new applications, including as example biomedical ones, for these new PTF copolymers beyond food packaging ones. Highly promising fully biobased random copolyesters, poly(trimethylene 2,5-furandicarboxylate- co -trimethylene sebacate) (PTFcoPTSeb), were synthesized by using bio derived 1,3-propanediol, dimethyl ester of 2,5- furandicarboxylic acid, and sebacic acid, through eco-friendly polycondensation in the melt. Copolymers with high molecular weight containing 5, 15, 25 mol % of PTSeb were obtained, and their chemical structure confirmed by 1H NMR and FTIR spectroscopy. The thermal, tensile and gas barrier properties and composability were studied in relation to the copolymer supramolecular structure. As expected, introduction of PTSeb co-units results in lowering of glass transition temperature of copolymers and improves their flexibility. Besides, all copolymers showed outstanding gas barrier properties to O 2 and CO 2 , with copolymer containing 15 mol % of PTSeb showing exceptional gas barrier properties, better than those of PTF and comparable to those of EVOH, currently used in multilayer packaging films. The same copolymer exhibited temperature induced shape memory behaviour. It was found that low amounts (15-25 mol %) of PTSeb in copolymer significantly modifies PTF thermal, mechanical and barrier properties and renders the final material compostable. Copolyesters containing 15 and 25 mol % of PTSeb can compete in some applications with commercially available compostable Ecoflex® polymer, but with markedly improved barrier properties. [ABSTRACT FROM AUTHOR]

Abstract: Modern day applications require use of multi-processor systems for reasons of performance, scalability and power efficiency. As more and more applications are integrated in a single system, mapping and analyzing them on a multi-processor platform becomes a multi-dimensional problem. Each possible set of applications that can be concurrently active leads to a different use-case (also referred to as scenario) that the system has to be verified and tested for. Analyzing the feasibility and resource utilization of all possible use-cases becomes very demanding and often infeasible. Therefore, in this paper, we highlight this issue of being able to analyze applications in isolation while still being able to reason about their overall behavior – also called composability. We make a number of novel observations about how arbitration plays an important role in system behavior. We compare two commonly used arbitration mechanisms, and highlight the properties that are important for such analysis. We conclude that none of these arbitration mechanisms provide the necessary features for analysis. They either suffer from scalability problems, or provide unreasonable estimates about performance, leading to waste of resources and/or undesirable performance. We further propose to use a Resource Manager (RM) to ensure applications meet their performance requirements. The basic functionalities of such a component are introduced. A high-level simulation model is developed to study the performance of RM, and a case study is performed for a system running an H.263 and a JPEG decoder. The case study illustrates at what granularity of control a resource manager can effectively regulate the progress of applications such that they meet their performance requirements. [Copyright &y& Elsevier]

We consider the thermodynamic stability conditions (TSC) on the Boltzmann entropies generalized by Tsallis’ q- and Kaniadakis’ κ-deformed logarithmic functions. It is shown that the corresponding TSCs are not necessarily equivalent to the concavity of the generalized Boltzmann entropies with respect to internal energy. Nevertheless, both the TSCs are equivalent to the positivity of standard heat capacity. [Copyright &y& Elsevier]

Time-triggered (TT) distributed real-time computing systems are moving into the mainstream for the implementation of safety-critical applications in the aerospace and automotive sectors. This paper introduces the basic principles of a TT real-time computing system, and elaborates on the benefits that can be gained from the availability of a global time base in general, and in specifying the linking interfaces of components in particular. It describes the concept of a temporal firewall that forms a fully specified operational interface of a component. The most important contribution of the TT-paradigm is the establishment of a sound basis for the composability of a design and the reuse of components in distributed real-time systems. [Copyright &y& Elsevier]

A permutation class C is said to be splittable if there exist two proper subclasses A , B ⊊ C such that any σ ∈ C can be red–blue colored so that the red (respectively, blue) subsequence of σ is order isomorphic to an element of A (respectively, B). The class C is said to be composable if there exists some number of proper subclasses A 1 , ... , A k ⊊ C such that any σ ∈ C can be written as α 1 ∘ ⋯ ∘ α k for some α i ∈ A i . We answer a question of Karpilovskij by showing that there exists a composable permutation class that is not splittable. We also give a condition under which an infinite composable class must be splittable. [ABSTRACT FROM AUTHOR]

• Herein, we reviewed the potential of bio-based food packaging materials as an alternative to petro- materials. • Effective deployment of suitable packaging material is a growing concern. • The broader applied spectrum of polymeric materials is discussed with suitable examples. In food industry, a growing concern is the use of suitable packaging material (i.e., biodegradable coatings and films) with enhanced thermal, mechanical and barrier characteristics to prevent from contamination and loss of foodstuff. Biobased polymer resources can be used for the development of biodegradable bioplastics. To achieve this goal, biopolymers should be economic, renewable and abundantly available. Bioplastic packaging materials based on renewable biomass could be used as sustainable alternative to petrochemically-originated plastic materials. This review summarizes the recent advancements in biopolymer-based coatings and films for active food packaging applications. Microbial polymers (PHA and PLA), wood-based polymers (cellulose, hemicellulose, starch & lignin), and protein-based polymers (gelatin, keratin, wheat gluten, soy protein and whey protein isolates) were among the materials most widely exploited for the development of smart packaging films. These biopolymers are able to synthesize coatings and films with good barrier properties against food borne pathogens and the transport of gases. Biobased reinforcements e.g., plant essential oils and natural additives to bioplastic films improve oxygen barrier, antibacterial and antifungal properties. To induce the desired functionality the simultaneous utilization of different synthetic and biobased polymers in the form of composites/blends is also an emerging area of research. Nanoscale reinforcements into bioplastic packaging have also been reported to improve packaging characteristics ultimately increasing food shelf life. The development of bioplastic/biocomposite and nanobiocomposites exhibits high potential to replace nonbiodegradable materials with characteristics comparable to fossil-based plastics, additionally, giving biodegradable and compostable characteristics. The idea of utilization of renewable biomass and the implications of biotechnology can firstly reduce the burden from fossil-resources, while secondly promoting biobased economy. [ABSTRACT FROM AUTHOR]