154 research outputs found

    EC Maritime Transport Policy and Regulation

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    When designing robust controllers, H-infinity synthesis is a common tool touse. The controllers that result from these algorithms are typically of very high order, which complicates implementation. However, if a constraint on the maximum order of the controller is set, that is lower than the order of the (augmented) system, the problem becomes nonconvex and it is relatively hard to solve. These problems become very complex, even when the order of the system is low. The approach used in this work is based on formulating the constraint onthe maximum order of the controller as a polynomial (or rational) equation.This equality constraint is added to the optimization problem of minimizingan upper bound on the H-innity norm of the closed loop system subjectto linear matrix inequality (LMI) constraints. The problem is then solvedby reformulating it as a partially augmented Lagrangian problem where theequality constraint is put into the objective function, but where the LMIsare kept as constraints. The proposed method is evaluated together with two well-known methodsfrom the literature. The results indicate that the proposed method hascomparable performance in most cases, especially if the synthesized con-troller has many parameters, which is the case if the system to be controlledhas many input and output signals

    The Shareholders’ Derivative-Claim Exception to the Attorney-Client Privilege

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    The use of an over-parametrized state-space model for system identification has some clear advantages: A single model structure covers the entire class of multivariable systems up to a given order. The over-parametrization also leads to the possibility to choose a numerically stable parametrization. During the parametric optimization the gradient calculations constitute the main computational part of the algorithm. Consequently using more than theminimal number of parameters requiredslows down thealgorithm. However, we show that for any chosen (over)-parametrization it is possible to reduce the gradientcalculations to the minimal amount by constructing the parameter subspace which is orthonormal to the tangent space of the manifold representing equivalent models

    Sometimes the Silence Can Be like the Thunder: Access to Pharmaceutical Data at the FDA

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    Those committed to the free exchange of scientific information have long complained about various restrictions on access to the FDA\u27s pharmaceutical data and the resultant restrictions on open discourse. A review of open-government procedures and litigation at the FDA demonstrates that the need for transparency at the agency extend well beyond the reach of any clinical trial registry

    Microsoft and the European Union Face Off Over Internet Privacy Concerns

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    Amidst what appears to be a multi-faceted attack by the European Union on Microsoft, the newest angle is the European Commission\u27s announcement last month that it was considering a formal investigation of Microsoft\u27s .Net Passport data processing system for possible violations of the European Union Data Privacy Directive. This iBrief explores the European Data Privacy Directive and seeks to explain why the European Commission believes .Net Passport may be in violation of its privacy policies and a case for further investigation

    Dual Control of an Integrator with Unknown Gain

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    The dual control law for an integrator with constant but unknown gain is computed. Numerical problems associated with the solution of the Bellman equation are reviewed. Properties of the dual control law are discussed. A representation which makes it easy to compare dual control with certainty equivalence and cautious control is also introduced

    A Quasi-Newton Interior Point Method for Low Order H-Infinity Controller Synthesis

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    Managing Without a Balance: Environmental Regulation in Light of Ecological Advances

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    When designing robust controllers, H-infinity synthesis is a common tool to use. The controllers that result from these algorithms are typically of very high order, which complicates implementation. However, if a constraint on the maximum order of the controller is set, that is lower than the order of the (augmented) system, the problem becomes nonconvex and it is relatively hard to solve. These problems become very complex, even when the order of the system is low. The approach used in this work is based on formulating the constraint on the maximum order of the controller as a polynomial (or rational) equation. By using the fact that the polynomial (or rational) is non-negative on the feasible set, the problem is reformulated as an optimization problem where the nonconvex function is to be minimized over a convex set defined by linear matrix inequalities. The proposed method is evaluated together with a well-known method from the literature. The results indicate that the proposed method performs slightly better

    Molecular identification of mosquito species Evaluation of a rapid DNA extraction method together with DNA barcoding as a tool for identification of species

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    Abstract The current method to determine a mosquito specimen to a certain species is by morphological keys basically following the taxonomy developed by Carl Linnaeus in the 1700. Since Watson and Crick presented their model of the double-helix DNA in 1953, a new era of molecular based taxonomic studies have revolutionized the field. The revolution is not in terms of how the classification of species is done but how the biological diversity is seen. However, morphological, ecological and behavioral characteristics are still important and are used together with the information a gene or whole genome can give. DNA barcoding is one of the promising methods for molecular identification. A small segment of a gene, approximately 400-1000 base pairs (bp), are examined by a Polymerase chain reaction (PCR) and sequencing. Like the barcodes in the grocery store these sequences work like unique ID: s for every species. This thesis shows how a fast DNA extraction method could be combined with DNA barcoding to get a 658-bp segment of the mitochondrial gene cytochrome c oxidase subunit 1 (COI) from different species of the mosquito family Culicidae. A total of 15 thoraxes or wings, from individual specimen of mosquitoes, were examined and 11 different barcode sequences could be retrieved. Six correspond to already published COI sequences and could therefore be determined to the species level, including a sequence from a new species for Sweden, Aedes (Ochlerotatus) nigrinus. All mosquitoes were collected during the national inventory of species in summer of 2012 in Sweden, "Myggjakten", and have been morphological examined by experts at the National Veterinary Institute (SVA) prior to molecular determination. This thesis also highlights the importance of building a reference library of barcode sequences, so DNA barcoding could become an effective diagnostic tool. Inventory projects like "Myggjakten" may, if repeated, provide excellent material for such a library collection of barcode data. 2 Sammanfattning När en stickmyggsart skall artbestämmas är den vanligaste metoden att använda morfologiska nycklar. I princip görs det här efter den taxonomi som Carl von Linne utvecklade på 1700-talet. Men sedan Watson och Crick presenterade sin DNA modell 1953 så har dock en ny era av molykylärt baserade metoder revolutionerat taxonomin. Förändringen består egentligen inte i hur vi klassificerar och använder taxonomin utan mer hur vi ser på den biologiska mångfalden. Morfologiska och ekologiska studier, samt studier av arters beteende, är fortfarande viktiga och komplementerar den molekylära informationen från ett genom eller från en enstaka gen. DNA barcoding är en av de lovande nya molekylära metoderna för artbestämning. Ett litet segment av en gen, på ungefär 400-1000 baspar (bp), undersöks med hjälp av polymeras-kedjereaktion (PCR) och sekvensering. Likt streckkoder i livsmedelsbutiken ger metoden ett unikt ID för varje art. Den här studien visar hur en snabb DNA-extraktionsmetod kan kombineras med DNA barcoding, för att ge en 658-bp lång DNA-sekvens, från den mitokondriella genen cytokrom c oxidas subunit 1 (COI) från olika arter av myggfamiljen Culicidae. I undersökningen ingick 15 mellankroppar eller vingar från individuella stickmyggor och av dessa kunde 11 olika barcode sekvenser utläsas. Sex av dessa stämde överrens med redan publicerade COI-sekvenser och kunde bestämmas till artnivå, varav en av sekvenserna kommer från den nyligen i Sverige funna morfologiskt artbestämda Aedes (Ochlerotatus) nigrinus. Stickmyggorna i detta arbete insamlades av privatpersoner på olika ställen i Sverige under sommaren 2012 i det nationella mygginsamlingsprojektet "Myggjakten". Dessa artbestämdes morfologiskt av personal på Statens veterinärmedicinska anstalt (SVA) innan de artbestämdes molekylärt. Det här arbetet belyser även vikten av att bygga upp ett referensbibliotek av barcode sekvenser för att DNA-barcoding ska kunna bli ett effektivt diagnostiskt verktyg vid studier av vektorburna zoonoser. Nationella projekt som Myggjakten kan vara mycket användbara för insamling av sådana data.

    Normal values for calprotectin in stool samples of infants from the population-based longitudinal born into life study

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    Faecal calprotectin is a protein used as a diagnostic marker for inflammatory bowel diseases. We determined upper limits for normal calprotectin values for neonatal, 6, 12 and 24 months old children using a turbidimetric immunoassay in a cohort of Swedish children. The advantage of the method is that opposite to previously used enzyme-linked immunosorbent assay (ELISA) method, it enables measuring single samples, and thus, shortens the analysis time significantly. There were 72 samples (41.7% female) collected neonatally, 63 samples (34.9% female) at 6 months, 60 samples (40.0% female) at 12 months and 51 samples (43.1% female) at 24 months. The upper limits for normal values were 233, 615, 136 and 57 microg mg(-1) for infants aged 0, 6, 12 and 24 months, respectively.The Swedish Research Council under Grants 2015-03477, 2010-15062-79050-11, 2015-02434; the Swedish Initiative for Research on Microdata in the Social And Medical Sciences (SIMSAM) framework under Grant 340-2013-5867Accepte
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