Hybrid Simulation Safety: Limbos and Zero Crossings

Physical systems can be naturally modeled by combining continuous and discrete models. Such hybrid models may simplify the modeling task of complex system, as well as increase simulation performance. Moreover, modern simulation engines can often efficiently generate simulation traces, but how do we know that the simulation results are correct? If we detect an error, is the error in the model or in the simulation itself? This paper discusses the problem of simulation safety, with the focus on hybrid modeling and simulation. In particular, two key aspects are studied: safe zero-crossing detection and deterministic hybrid event handling. The problems and solutions are discussed and partially implemented in Modelica and Ptolemy II

MPEG Reconfigurable Video Coding

WOS - ISBN: 978-1-4419-6344-4The currentmonolithic and lengthy scheme behind the standardization and the design of new video coding standards is becoming inappropriate to satisfy the dynamism and changing needs of the video coding community. Such a scheme and specification formalism do not enable designers to exploit the clear commonalities between the different codecs, neither at the level of the specification nor at the level of the implementation. Such a problem is one of the main reasons for the typical long time interval elapsing between the time a new idea is validated until it is implemented in consumer products as part of a worldwide standard. The analysis of this problem originated a new standard initiative within the ISO/IEC MPEG committee, called Reconfigurable Video Coding (RVC). The main idea is to develop a video coding standard that overcomes many shortcomings of the current standardization and specification process by updating and progressively incrementing a modular library of components. As the name implies, flexibility and reconfigurability are new attractive features of the RVC standard. The RVC framework is based on the usage of a new actor/dataflow oriented language called CAL for the specification of the standard library and the instantiation of the RVC decoder model. CAL dataflow models expose the intrinsic concurrency of the algorithms by employing the notions of actor programming and dataflow. This chapter gives an overview of the concepts and technologies building the standard RVC framework and the non standard tools supporting the RVC model from the instantiation and simulation of the CAL model to the software and/or hardware code synthesis

Pre-participation Cardiac Screening in Young Athletes: Models and Criteria

This is the second of two review articles focusing on the value of preparticipation cardiac screening in young athletes. The article focuses on the efficacy of the resting 12-lead electrocardiogram (ECG), physical examination, and medical history questionnaire, which commonly make up the first stage of a cardiac screening protocol. The review then focuses on specific structural and electrical abnormalities which are responsible for sudden cardiac death (SCD) in young athletes – the most common of which is hypertrophic cardiomyopathy. The identification of appropriate ‘red flag’ signs and symptoms is essential for teasing out potential pathological conditions and allowing differentiation from often benign physiological adaptations. The final section provides guidance on how the resting 12-lead ECG can be used to separate pathological from physiological adaptations in young athletes

Structural Synthesis for GXW Specifications

We define the GXW fragment of linear temporal logic (LTL) as the basis for synthesizing embedded control software for safety-critical applications. Since GXW includes the use of a weak-until operator we are able to specify a number of diverse programmable logic control (PLC) problems, which we have compiled from industrial training sets. For GXW controller specifications, we develop a novel approach for synthesizing a set of synchronously communicating actor-based controllers. This synthesis algorithm proceeds by means of recursing over the structure of GXW specifications, and generates a set of dedicated and synchronously communicating sub-controllers according to the formula structure. In a subsequent step, 2QBF constraint solving identifies and tries to resolve potential conflicts between individual GXW specifications. This structural approach to GXW synthesis supports traceability between requirements and the generated control code as mandated by certification regimes for safety-critical software. Synthesis for GXW specifications is in PSPACE compared to 2EXPTIME-completeness of full-fledged LTL synthesis. Indeed our experimental results suggest that GXW synthesis scales well to industrial-sized control synthesis problems with 20 input and output ports and beyond.Comment: The long (including appendix) version being reviewed by CAV'16 program committee. Compared to the submitted version, one author (out of her wish) is moved to the Acknowledgement. (v2) Corrected typos. (v3) Add an additional remark over environment assumption and easy corner case

Whole-body MRI for preventive health screening:A systematic review of the literature

Background The yield of whole-body MRI for preventive health screening is currently not completely clear. Purpose To systematically review the prevalence of whole-body MRI findings in asymptomatic subjects. Study Type Systematic review and meta-analysis. Subjects MEDLINE and Embase were searched for original studies reporting whole-body MRI findings in asymptomatic adults without known disease, syndrome, or genetic mutation. Twelve studies, comprising 5373 asymptomatic subjects, were included. Field Strength/Sequence 1.5T or 3.0T, whole-body MRI. Assessment The whole-body MRI literature findings were extracted and reviewed by two radiologists in consensus for designation as either critical or indeterminate incidental finding. Statistical Tests Data were pooled using a random effects model on the assumption that most subjects had 5-year) verification of negative findings. Only one study reported false-negative findings, with a proportion of 2.0%. Data Conclusion Prevalence of critical and indeterminate incidental whole-body MRI findings in asymptomatic subjects is overall substantial and with variability dependent to some degree on the protocol. Verification data are lacking. The proportion of false-positive findings appears to be substantial. Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:1489-1503

Modeling Resolution of Resources Contention in Synchronous Data Flow Graphs

Synchronous Data Flow graphs are widely adopted in the designing of streaming applications, but were originally formulated to describe only how an application is partitioned and which data are exchanged among different tasks. Since Synchronous Data Flow graphs are often used to describe and evaluate complete design solutions, missing information (e.g., mapping, scheduling, etc.) has to be included in them by means of further actors and channels to obtain accurate evaluations. To address this issue preserving the simplicity of the representation, techniques that model data transfer delays by means of ad-hoc actors have been proposed, but they model independently each communication ignoring contentions. Moreover, they do not usually consider at all delays due to buffer contentions, potentially overestimating the throughput of a design solution. In this paper a technique to extend Synchronous Data Flow graphs by adding ad-hoc actors and channels to model resolution of resources contentions is proposed. The results show that the number of added actors and channels is limited but that they can significantly increase the Synchronous Data Flow graph accuracy

Production and optimization of L-asparaginase by Bacillus sp. KK2S4 from corn cob

L-Asparaginase (L-asparagine amido hydrolase, E.C.3.5.1.1) is an important enzyme which has antitumor properties. This paper describes the production and optimization of L-asparaginase by Bacillus sp. KK2S4 utilization of ground corn cob waste as substrate to reduce and manage the waste in our environment. Thirty-nine (39) bacterial isolates were screened for their L-asparaginase productivity and protein content. Only Bacillus sp. KK2S4 was identified before and selected as the most potent isolate. Modified M9 (MM9) minimal complete medium (glucose free) was used as production media for enzyme production. The highest enzyme production was detected at pH 5.0 in presence of lactose and NaNO3 as the best carbon and nitrogen sources with high activity increasing percentage of 1058.9, 377.3 and 566.7%, respectively.Keywords: L-Asparaginase production, corn cob waste, enzyme optimization, anti-tumor agentAfrican Journal of Biotechnology Vol. 12(19), pp. 2654-265

Bacteria of the Burkholderia cepacia complex are cyanogenic under biofilm and colonial growth conditions

<p>Abstract</p> <p>Background</p> <p>The <it>Burkholderia cepacia </it>complex (Bcc) is a collection of nine genotypically distinct but phenotypically similar species. They show wide ecological diversity and include species that are used for promoting plant growth and bio-control as well species that are opportunistic pathogens of vulnerable patients. Over recent years the Bcc have emerged as problematic pathogens of the CF lung. <it>Pseudomonas aeruginosa </it>is another important CF pathogen. It is able to synthesise hydrogen cyanide (HCN), a potent inhibitor of cellular respiration. We have recently shown that HCN production by <it>P. aeruginosa </it>may have a role in CF pathogenesis. This paper describes an investigation of the ability of bacteria of the Bcc to make HCN.</p> <p>Results</p> <p>The genome of <it>Burkholderia cenocepacia </it>has 3 putative HCN synthase encoding (<it>hcnABC</it>) gene clusters. <it>B. cenocepacia </it>and all 9 species of the Bcc complex tested were able to make cyanide at comparable levels to <it>P. aeruginosa</it>, but only when grown surface attached as colonies or during biofilm growth on glass beads. In contrast to <it>P. aeruginosa </it>and other cyanogenic bacteria, cyanide was not detected during planktonic growth of Bcc strains.</p> <p>Conclusion</p> <p>All species in the Bcc are cyanogenic when grown as surface attached colonies or as biofilms.</p

Newspaper representation and power relations in infrastructure projects: a case study of Hong Kong’s Express Rail Link

This paper explores newspapers’ representation of different actors in infrastructure projects, and analyses the power relations between them through a case study in Hong Kong. The case in question is the highly controversial Express Rail Link, which connects Hong Kong to the extensive high-speed railway network in mainland China. It finds that under an immature democratic system, opponents’ political power and free press play important roles in forcing the government to make concessions outside the formal framework. The methodological framework employs a concept that takes media representation as a reflection of power [Van Dijk, Teun A. 1996. “Discourse, Power and Access.” In Texts and Practices: Readings in Critical Discourse Analysis, edited by Carmen Caldas-Coulthard and Malcolm Coulthard, 84–104. London: Routledge], and three theories seldom used in the planning field – Indexing Theory [Bennett, W. Lance. 1990. “Toward a Theory of Press-State Relations in the United States.” Journal of Communication 40 (2): 103–127. doi:10.1111/j.1460-2466.1990.tb02265.x], Agenda Setting Theory [McCombs, Maxwell E., and Donald L. Shaw. 1972. “The Agenda-Setting Function of Mass Media.” Public Opinion Quarterly 36 (2): 176–187] and Law of Anticipated Reactions [Zelditch, Morris, and John Ford. 1994. “Uncertainty, Potential Power, and Nondecisions.” Social Psychology Quarterly 57 (1): 64]. A new method for Critical Discourse Analysis, in the form of colour charts, is developed to portray the competition for representation in newspapers of different actors, paying special attention to power inequalities and which actors gain access to newspaper discourse and how they use it to convey specific messages. In this study, 500 newspaper articles (from two key newspapers – SCMP and Apple Daily) and 75 government publications in Hong Kong are analysed