212 research outputs found

    Enhancing the EAST-ADL error model with HiP-HOPS semantics

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    EAST-ADL is a domain-specific modelling language for the engineering of automotive embedded systems. The language has abstractions that enable engineers to capture a variety of information about design in the course of the lifecycle — from requirements to detailed design of hardware and software architectures. The specification of the EAST-ADL language includes an error model extension which documents language structures that allow potential failures of design elements to be specified locally. The effects of these failures are then later assessed in the context of the architecture design. To provide this type of useful assessment, a language and a specification are not enough; a compiler-like tool that can read and operate on a system specification together with its error model is needed. In this paper we integrate the error model of EAST-ADL with the precise semantics of HiP-HOPS — a state-of-the-art tool that enables dependability analysis and optimization of design models. We present the integration concept between EAST-ADL structure and HiP-HOPS error propagation logic and its transformation into the HiP-HOPS model. Source and destination models are represented using the corresponding XML formats. The connection of these two models at tool level enables practical EAST-ADL designs of embedded automotive systems to be analysed in terms of dependability, i.e. safety, reliability and availability. In addition, the information encoded in the error model can be re-used across different contexts of application with the associated benefits for cost reduction, simplification, and rationalisation of dependability assessments in complex engineering designs

    Module-based quality system functionality evaluation in production logistics

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    Purpose: This paper addresses a comprehensive modeling and functionality evaluation of a module-based quality system in production logistics at the highest domain abstract level of business processes. Design/methodology/approach: All domain quality business processes and quality data transactions are modeled using BPMN and UML tools and standards at the business process and data modeling. A modular web-based prototype is developed to evaluate the models addressing the quality information system functionality requirements and modularity in production logistics through data scenarios and data queries. Findings: Using the object-oriented technique in design at the highest domain level, the proposed models are subject further development in the lower levels for the implementing case. The models are specifically able to manipulate all quality operations including remedy and control in a lot-based make-to-order production logistics system as an individual module. Practical implications: Due to the specification of system as domain design structure, all proposed BPMs, data models, and the actual database prototype are seen referential if not a solution as a practical “to-be” quality business process re-engineering template. Originality/value: this paper sets out to provide an explanatory approach using different practical technique at modeling steps as well as the prototype implementation.Peer Reviewe

    Towards Harmonizing Multiple Architecture Description Languages for Real-Time Embedded Systems

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    Abstract-The increasing complexity of real-time embedded systems requires appropriate methods and techniques to support the development including the specification and analysis of different architectural aspects. A large number of architectural description languages (ADL) have been proposed with varying focus and application domains. There is a need for harmonization of these ADLs. This can be from develoloping and understanding of how they differ or could be synergistically combined for increasing the overall development efficiency and fulfilling the ever increasing functional and non-functional requirements on a system. This paper addresses this issue and focuses on four different ADLs: EAST-ADL, AUTOSAR, AADL and Rubus. In this work we compare these ADLs, identify possible usage scenarios involving more than one ADL and discuss some of the underlying challenges. A representative industrial case study of a brake-by-wire system is used to support the work

    Lower bound on the blow-up rate of the axisymmetric Navier-Stokes equations

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    Consider axisymmetric strong solutions of the incompressible Navier-Stokes equations in R3\R^3 with non-trivial swirl. Such solutions are not known to be globally defined, but it is shown in \cite{MR673830} that they could only blow up on the axis of symmetry. Let zz denote the axis of symmetry and rr measure the distance to the z-axis. Suppose the solution satisfies the pointwise scale invariant bound v(x,t)C(r2t)1/2|v (x,t)| \le C_*{(r^2 -t)^{-1/2}} for T0t<0-T_0\le t < 0 and 0<C<0<C_*<\infty allowed to be large, we then prove that vv is regular at time zero.Comment: 25 page

    Thermodynamic plant optimization for the production of carbon acid as an element of trigenerating turbo unit on the organic Renkin cycle

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    Произведен эксергетический анализ установки по производству жидкой и газообразной углекислоты с возможностью получения холода в схеме тригенерации. Представлен цикл в P–h-координатах данной установки. Построена диаграмма Грассмана–Шаргута установки по производству углекислоты. Выявлено, что при помощи дополнительного элемента в виде внешнего источника охлаждения (системы оборотного водоснабжения с градирней либо холодной воды, поступающей на объект из поверхностных или подземных источников) можно значительно снизить расход рабочего тела в установке и, как следствие – потери в цикле. Построенные диаграммы Грассмана–Шаргута первоначальной и измененной схем установок показали, что данное мероприятие позволяет снизить затраты эксергии на привод компрессора до 2,97 %.The exergy analysis of the installation for the production of liquid and gaseous carbon dioxide has been done with the possibility of obtaining a cold in the trigeneration scheme. The cycle in P–h-coordinates of the given setup is presented. The Grassmann–Shargut diagram of the installation for the production of carbon dioxide was constructed. It was revealed that with the help of an additional element in the form of an external cooling source (a circulating water supply system with a cooling tower, or cold water supplied to the object from surface or underground sources), it is possible to significantly reduce the consumption of the working fluid in the installation and, as a consequence, losses in the cycle. The designed Grassmann–Shargut diagrams of the initial and modified plant diagrams showed that this measure allows reducing the exergy costs for the compressor drive to 2.97%

    Exact soliton solution and inelastic two-soliton collision in spin chain driven by a time-dependent magnetic field

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    We investigate dynamics of exact N-soliton trains in spin chain driven by a time-dependent magnetic field by means of an inverse scattering transformation. The one-soliton solution indicates obviously the spin precession around the magnetic field and periodic shape-variation induced by the time varying field as well. In terms of the general soliton solutions N-soliton interaction and particularly various two-soliton collisions are analyzed. The inelastic collision by which we mean the soliton shape change before and after collision appears generally due to the time varying field. We, moreover, show that complete inelastic collisions can be achieved by adjusting spectrum and field parameters. This may lead a potential technique of shape control of soliton.Comment: 5 pages, 5 figure

    A Single Amino Acid Substitution Changes Antigenicity of ORF2-Encoded Proteins of Hepatitis E Virus

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    Extensive genomic diversity has been observed among hepatitis E virus (HEV) strains. However, the implication of the genetic heterogeneity on HEV antigenic properties is uncertain. In this study, monoclonal antibodies (Mabs) against truncated ORF2-encoded proteins (aa452–617, designated p166 proteins) derived from HEV strains of Burma (genotype 1a, p166Bur), Pakistan (1b, p166Pak) and Morocco (1c, p166Mor) were raised and used for identification of HEV antigenic diversity. Six Mabs reacted to these 3 p166 proteins as well as p166 proteins constructed from strains derived from Mexico (genotype 2), US (genotype 3) and China (genotype 4), indicating the existence of pan-genotypic epitopes. Two Mabs, 1B5 and 6C7, reacted with p166Bur and p166Mor, but not p166Pak or p166s derived from genotypes 2, 3, and 4, indicating that these 2 Mabs recognized strain-specific HEV epitopes. Both the common and specific epitopes could not be mapped by 23 synthetic peptides spanning the p166Bur sequence, suggesting that they are confirmation-dependent. Comparative sequence analysis showed that p166Bur and p166Mor shared an identical aa sequence along their entire lengths, whereas for p166Pak the aas occupying positions 606 and 614 are different from aas at corresponding positions of p166Bur and p166Mor. Reactivity between 1B5 and p166Bur was abrogated with mutation of p166Bur/A606V, whereas p166Pak acquired the reactivity to 1B5 with mutation of p166Pak/V606A. However, mutations of p166Bur/L614M and P166Pak/M614L did not affect the immunoreactivity. Therefore, the aa occupying position 606 plays a critical role in maintaining the antigenicity of the HEV p166 proteins

    Structural and Functional Diversity of Acidic Scorpion Potassium Channel Toxins

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    Background: Although the basic scorpion K + channel toxins (KTxs) are well-known pharmacological tools and potential drug candidates, characterization the acidic KTxs still has the great significance for their potential selectivity towards different K + channel subtypes. Unfortunately, research on the acidic KTxs has been ignored for several years and progressed slowly. Principal Findings: Here, we describe the identification of nine new acidic KTxs by cDNA cloning and bioinformatic analyses. Seven of these toxins belong to three new a-KTx subfamilies (a-KTx28, a-KTx29, and a-KTx30), and two are new members of the known k-KTx2 subfamily. ImKTx104 containing three disulfide bridges, the first member of the a-KTx28 subfamily, has a low sequence homology with other known KTxs, and its NMR structure suggests ImKTx104 adopts a modified cystine-stabilized a-helix-loop-b-sheet (CS-a/b) fold motif that has no apparent a-helixs and b-sheets, but still stabilized by three disulfide bridges. These newly described acidic KTxs exhibit differential pharmacological effects on potassium channels. Acidic scorpion toxin ImKTx104 was the first peptide inhibitor found to affect KCNQ1 channel, which is insensitive to the basic KTxs and is strongly associated with human cardiac abnormalities. ImKTx104 selectively inhibited KCNQ1 channel with a Kd of 11.69 mM, but was less effective against the basic KTxs-sensitive potassium channels. In addition to the ImKTx104 toxin, HeTx204 peptide, containing a cystine-stabilized a-helix-loop-helix (CS-a/a) fold scaffold motif
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