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Sample records for involves rolling circle

  1. Rolling circle amplification of metazoan mitochondrialgenomes

    Energy Technology Data Exchange (ETDEWEB)

    Simison, W. Brian; Lindberg, D.R.; Boore, J.L.

    2005-07-31

    Here we report the successful use of rolling circle amplification (RCA) for the amplification of complete metazoan mt genomes to make a product that is amenable to high-throughput genome sequencing techniques. The benefits of RCA over PCR are many and with further development and refinement of RCA, the sequencing of organellar genomics will require far less time and effort than current long PCR approaches.

  2. Controlled Microwave Heating Accelerates Rolling Circle Amplification.

    Science.gov (United States)

    Yoshimura, Takeo; Suzuki, Takamasa; Mineki, Shigeru; Ohuchi, Shokichi

    2015-01-01

    Rolling circle amplification (RCA) generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.

  3. Controlled Microwave Heating Accelerates Rolling Circle Amplification.

    Directory of Open Access Journals (Sweden)

    Takeo Yoshimura

    Full Text Available Rolling circle amplification (RCA generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.

  4. The rolling circle amplification and next generation sequencing ...

    African Journals Online (AJOL)

    Rolling circle amplification is a simple approach of enriching populations of single-stranded DNA plant begomovirus genomes (genus, Begomovirus; family, Geminiviridae). This is an innovative approach that utilizes the robustness of the bacteriophage phi29 DNA polymerase used in circle amplification, together with deep ...

  5. Yoctomole electrochemical genosensing of Ebola virus cDNA by rolling circle and circle to circle amplification.

    Science.gov (United States)

    Carinelli, S; Kühnemund, M; Nilsson, M; Pividori, M I

    2017-07-15

    This work addresses the design of an Ebola diagnostic test involving a simple, rapid, specific and highly sensitive procedure based on isothermal amplification on magnetic particles with electrochemical readout. Ebola padlock probes were designed to detect a specific L-gene sequence present in the five most common Ebola species. Ebola cDNA was amplified by rolling circle amplification (RCA) on magnetic particles. Further re-amplification was performed by circle-to-circle amplification (C2CA) and the products were detected in a double-tagging approach using a biotinylated capture probe for immobilization on magnetic particles and a readout probe for electrochemical detection by square-wave voltammetry on commercial screen-printed electrodes. The electrochemical genosensor was able to detect as low as 200 ymol, corresponding to 120 cDNA molecules of L-gene Ebola virus with a limit of detection of 33 cDNA molecules. The isothermal double-amplification procedure by C2CA combined with the electrochemical readout and the magnetic actuation enables the high sensitivity, resulting in a rapid, inexpensive, robust and user-friendly sensing strategy that offers a promising approach for the primary care in low resource settings, especially in less developed countries. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. CHARACTERIZATION OF SINGLE-STRAND ORIGINS OF CRYPTIC ROLLING-CIRCLE PLASMIDS FROM BACILLUS-SUBTILIS

    NARCIS (Netherlands)

    MEIJER, WJJ; VENEMA, G; BRON, S

    1995-01-01

    In this paper we describe the isolation and characterization of single strand origins (SSOs) of several cryptic Bacillus subtilis plasmids which use the rolling-circle mechanism of replication, The plasmids used in this study involved pTA1015, pTA1020, pTA1030, pTA1040, pTA1050 and pTA1060, The SSO

  7. Primer Extension Mutagenesis Powered by Selective Rolling Circle Amplification

    Science.gov (United States)

    Huovinen, Tuomas; Brockmann, Eeva-Christine; Akter, Sultana; Perez-Gamarra, Susan; Ylä-Pelto, Jani; Liu, Yuan; Lamminmäki, Urpo

    2012-01-01

    Primer extension mutagenesis is a popular tool to create libraries for in vitro evolution experiments. Here we describe a further improvement of the method described by T.A. Kunkel using uracil-containing single-stranded DNA as the template for the primer extension by additional uracil-DNA glycosylase treatment and rolling circle amplification (RCA) steps. It is shown that removal of uracil bases from the template leads to selective amplification of the nascently synthesized circular DNA strand carrying the desired mutations by phi29 DNA polymerase. Selective RCA (sRCA) of the DNA heteroduplex formed in Kunkel's mutagenesis increases the mutagenesis efficiency from 50% close to 100% and the number of transformants 300-fold without notable diversity bias. We also observed that both the mutated and the wild-type DNA were present in at least one third of the cells transformed directly with Kunkel's heteroduplex. In contrast, the cells transformed with sRCA product contained only mutated DNA. In sRCA, the complex cell-based selection for the mutant strand is replaced with the more controllable enzyme-based selection and less DNA is needed for library creation. Construction of a gene library of ten billion members is demonstrated with the described method with 240 nanograms of DNA as starting material. PMID:22355397

  8. Sensitive Blu-ray detection of clustered rolling circle products for molecular Diagnostics

    DEFF Research Database (Denmark)

    Ahlford, Annika; Donolato, Marco; Antunes, Paula Soares Martins

    2014-01-01

    In this paper we present a method for low cost and rapid sensing of nucleic acids (NA) for infectious diagnostics, where isothermal rolling circle amplification (RCA) products, specifically generated by the presence of the human pathogen Pseudomonas aeruginosa (PA), are bound to magnetic nanopart......In this paper we present a method for low cost and rapid sensing of nucleic acids (NA) for infectious diagnostics, where isothermal rolling circle amplification (RCA) products, specifically generated by the presence of the human pathogen Pseudomonas aeruginosa (PA), are bound to magnetic...

  9. Real-time single-molecule observation of rolling-circle DNA replication

    NARCIS (Netherlands)

    Tanner, Nathan A.; Loparo, Joseph J.; Hamdan, Samir M.; Jergic, Slobodan; Dixon, Nicholas E.; Oijen, Antoine M. van

    2009-01-01

    We present a simple technique for visualizing replication of individual DNA molecules in real time. By attaching a rolling-circle substrate to a TIRF microscope-mounted flow chamber, we are able to monitor the progression of single-DNA synthesis events and accurately measure rates and processivities

  10. The rolling-circle melting-pot model for porcine circovirus DNA replication

    Science.gov (United States)

    A stem-loop structure, formed by a pair of inverted repeats during DNA replication, is a conserved feature at the origin of DNA replication (Ori) among plant and animal viruses, bacteriophages and plasmids that replicate their genomes via the rolling-circle replication (RCR) mechanism. Porcine circo...

  11. Sequence analysis and characterization of rolling-circle replicating plasmid pVCM01 from Salmonella enterica

    Directory of Open Access Journals (Sweden)

    Penido, A. F. B.

    2013-12-01

    Full Text Available Aims: Characterization of cryptic plasmid pVCM01 (accession number JX133088 isolated from Salmonella enterica Enteritidis. Methodology and results: The complete sequence of pVCM01 was obtained. This plasmid possesses 1981 bp, with G+C content of 57% in agreement of the range of Salmonella genomic DNA. pVCM01 has a high degree of similarity to pB and pJ plasmids. It possesses six main open reading frames, only one have a very high degree of amino acid identity with protein involved in the rolling-circle-like replication (RCR. Based on the sequence similarities, pVCM01 plasmid belonged to the pC194/pUB110 rolling-circle replicating plasmid family. The Rep pVCM01 possesses the motifs: FLTLTVRN, HPHFHTL, SGDGYVKHERW, which were present in all Rep proteins. Conclusion, significance and impact of study: The small size of pVCM01 plasmid and its stability in E. coli cells, make it an attractive candidate to develop new vectors, such as cloning and/or expression vector.

  12. DNA Hydrogel with Tunable pH-Responsive Properties Produced by Rolling Circle Amplification.

    Science.gov (United States)

    Xu, Wanlin; Huang, Yishun; Zhao, Haoran; Li, Pan; Liu, Guoyuan; Li, Jing; Zhu, Chengshen; Tian, Leilei

    2017-12-22

    Recently, smart DNA hydrogels, which are generally formed by the self-assembly of oligonucleotides or through the cross-linking of oligonucleotide-polymer hybrids, have attracted tremendous attention. However, the difficulties of fabricating DNA hydrogels limit their practical applications. We report herein a novel method for producing pH-responsive hydrogels by rolling circle amplification (RCA). In this method, pH-sensitive cross-linking sites were introduced into the polymeric DNA chains during DNA synthesis. As the DNA sequence can be precisely defined by its template, the properties of such hydrogels can be finely tuned in a very facile way through template design. We have investigated the process of hydrogel formation and pH-responsiveness to provide rationales for functional hydrogel design based on the RCA reaction. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Digital quantification of rolling circle amplified single DNA molecules in a resistive pulse sensing nanopore.

    Science.gov (United States)

    Kühnemund, M; Nilsson, M

    2015-05-15

    Novel portable, sensitive and selective DNA sensor methods for bio-sensing applications are required that can rival conventionally used non-portable and expensive fluorescence-based sensors. In this paper, rolling circle amplification (RCA) products are detected in solution and on magnetic particles using a resistive pulse sensing (RPS) nanopore. Low amounts of DNA molecules are detected by padlock probes which are circularized in a strictly target dependent ligation reaction. The DNA-padlock probe-complex is captured on magnetic particles by sequence specific capture oligonucleotides and amplified by a short RCA. Subsequent RPS analysis is used to identify individual particles with single attached RCA products from blank particles. This proof of concept opens up for a novel non-fluorescent digital DNA quantification method that can have many applications in bio-sensing and diagnostic approaches. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Rapid screening for human-pathogenic Mucorales using rolling circle amplification.

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    Dolatabadi, S; Najafzadeh, M J; de Hoog, G S

    2014-12-01

    Mucormycosis has emerged as a relatively common severe mycosis in patients with haematological and allogeneic stem cell transplantation. Source of transmission is from unidentified sources in the environment. Early diagnosis of infection and its source of contamination are paramount for rapid and appropriate therapy. In this study, rolling circle amplification (RCA) is introduced as a sensitive, specific and reproducible isothermal DNA amplification technique for rapid molecular identification of six of the most virulent species (Rhizopus microsporus, R. arrhizus var. arrhizus, R. arrhizus var. delemar, Mucor irregularis, Mucor circinelloides, Lichtheimia ramosa, Lichtheimia corymbifera). DNAs of target species were successfully amplified, with no cross reactivity between species. RCA can be considered as a rapid detection method with high specificity and sensitivity, suitable for large screening. © 2014 Blackwell Verlag GmbH.

  15. A rolling circle replication mechanism produces multimeric lariats of mitochondrial DNA in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Samantha C Lewis

    2015-02-01

    Full Text Available Mitochondrial DNA (mtDNA encodes respiratory complex subunits essential to almost all eukaryotes; hence respiratory competence requires faithful duplication of this molecule. However, the mechanism(s of its synthesis remain hotly debated. Here we have developed Caenorhabditis elegans as a convenient animal model for the study of metazoan mtDNA synthesis. We demonstrate that C. elegans mtDNA replicates exclusively by a phage-like mechanism, in which multimeric molecules are synthesized from a circular template. In contrast to previous mammalian studies, we found that mtDNA synthesis in the C. elegans gonad produces branched-circular lariat structures with multimeric DNA tails; we were able to detect multimers up to four mtDNA genome unit lengths. Further, we did not detect elongation from a displacement-loop or analogue of 7S DNA, suggesting a clear difference from human mtDNA in regard to the site(s of replication initiation. We also identified cruciform mtDNA species that are sensitive to cleavage by the resolvase RusA; we suggest these four-way junctions may have a role in concatemer-to-monomer resolution. Overall these results indicate that mtDNA synthesis in C. elegans does not conform to any previously documented metazoan mtDNA replication mechanism, but instead are strongly suggestive of rolling circle replication, as employed by bacteriophages. As several components of the metazoan mitochondrial DNA replisome are likely phage-derived, these findings raise the possibility that the rolling circle mtDNA replication mechanism may be ancestral among metazoans.

  16. Analytically Sensitive Protein Detection in Microtiter Plates by Proximity Ligation with Rolling Circle Amplification.

    Science.gov (United States)

    Ebai, Tonge; Souza de Oliveira, Felipe Marques; Löf, Liza; Wik, Lotta; Schweiger, Caroline; Larsson, Anders; Keilholtz, Ulrich; Haybaeck, Johannes; Landegren, Ulf; Kamali-Moghaddam, Masood

    2017-09-01

    Detecting proteins at low concentrations in plasma is crucial for early diagnosis. Current techniques in clinical routine, such as sandwich ELISA, provide sensitive protein detection because of a dependence on target recognition by pairs of antibodies, but detection of still lower protein concentrations is often called for. Proximity ligation assay with rolling circle amplification (PLARCA) is a modified proximity ligation assay (PLA) for analytically specific and sensitive protein detection via binding of target proteins by 3 antibodies, and signal amplification via rolling circle amplification (RCA) in microtiter wells, easily adapted to instrumentation in use in hospitals. Proteins captured by immobilized antibodies were detected using a pair of oligonucleotide-conjugated antibodies. Upon target recognition these PLA probes guided oligonucleotide ligation, followed by amplification via RCA of circular DNA strands that formed in the reaction. The RCA products were detected by horseradish peroxidase-labeled oligonucleotides to generate colorimetric reaction products with readout in an absorbance microplate reader. We compared detection of interleukin (IL)-4, IL-6, IL-8, p53, and growth differentiation factor 15 (GDF-15) by PLARCA and conventional sandwich ELISA or immuno-RCA. PLARCA detected lower concentrations of proteins and exhibited a broader dynamic range compared to ELISA and iRCA using the same antibodies. IL-4 and IL-6 were detected in clinical samples at femtomolar concentrations, considerably lower than for ELISA. PLARCA offers detection of lower protein levels and increased dynamic ranges compared to ELISA. The PLARCA procedure may be adapted to routine instrumentation available in hospitals and research laboratories. © 2017 American Association for Clinical Chemistry.

  17. High-throughput genotyping of single nucleotide polymorphisms with rolling circle amplification

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    Sun Zhenyu

    2001-08-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs are the foundation of powerful complex trait and pharmacogenomic analyses. The availability of large SNP databases, however, has emphasized a need for inexpensive SNP genotyping methods of commensurate simplicity, robustness, and scalability. We describe a solution-based, microtiter plate method for SNP genotyping of human genomic DNA. The method is based upon allele discrimination by ligation of open circle probes followed by rolling circle amplification of the signal using fluorescent primers. Only the probe with a 3' base complementary to the SNP is circularized by ligation. Results SNP scoring by ligation was optimized to a 100,000 fold discrimination against probe mismatched to the SNP. The assay was used to genotype 10 SNPs from a set of 192 genomic DNA samples in a high-throughput format. Assay directly from genomic DNA eliminates the need to preamplify the target as done for many other genotyping methods. The sensitivity of the assay was demonstrated by genotyping from 1 ng of genomic DNA. We demonstrate that the assay can detect a single molecule of the circularized probe. Conclusions Compatibility with homogeneous formats and the ability to assay small amounts of genomic DNA meets the exacting requirements of automated, high-throughput SNP scoring.

  18. On-chip Detection of Rolling Circle Amplified DNA Molecules from Bacillus Globigii spores and Vibrio Cholerae

    DEFF Research Database (Denmark)

    Østerberg, Frederik Westergaard; Rizzi, Giovanni; Donolato, Marco

    2014-01-01

    For the first time DNA coils formed by rolling circle amplification are quantified on-chip by Brownian relaxation measurements on magnetic nanobeads using a magnetoresistive sensor. No external magnetic fields are required besides the magnetic field arising from the current through the sensor...

  19. Electrochemical aptasensor for highly sensitive determination of cocaine using a supramolecular aptamer and rolling circle amplification

    International Nuclear Information System (INIS)

    Shen, Bo; Yan, Yurong; Tang, Renkuan; Li, Yongguo; Li, Jianbo; Cheng, Wei; Ju, Huangxian; Ding, Shijia

    2015-01-01

    We report on a novel strategy for the electrochemical detection of cocaine. It is based on the use of a supramolecular aptamer, rolling circle amplification (RCA), and multiplex binding of a biotin-strepavidin system. The aptamer fragments were assembled to a supramolecular aptamer which, in the presence of cocaine, conjugates to streptavidin for anchoring of biotinylated circular DNA. This initiates RCA and enables sensitive electrochemical-enzymatic readout. A significant signal amplification was obtained by using streptavidin linked to alkaline phosphatase that binds to the remaining biotinylated detection probes and catalyzes the hydrolysis of the synthetic enzyme substrate α-naphthylphosphate. This dual amplification strategy tremendously increases the detection limit of the aptasensor. Under optimal conditions and using differential pulse voltammetry, cocaine can be detected in the concentration range between 2 and 500 nM with a detection limit as low as 1.3 nM (at S/N = 3). The method is specific and acceptably reproducible. It was successfully applied to the detection of cocaine in (spiked) urine samples. The data were in good agreement with those obtained by the GC-MS reference method. (author)

  20. An aptasensor for staphylococcus aureus based on nicking enzyme amplification reaction and rolling circle amplification.

    Science.gov (United States)

    Xu, Jingguo; Guo, Jia; Maina, Sarah Wanjiku; Yang, Yumeng; Hu, Yimin; Li, Xuanxuan; Qiu, Jiarong; Xin, Zhihong

    2018-05-15

    An ultra-sensitive aptamer-based biosensor for the detection of staphylococcus aureus was established by adopting the nicking enzyme amplification reaction (NEAR) and the rolling circle amplification (RCA) technologies. Aptamer-probe (AP), containing an aptamer and a probe sequence, was developed to act as the recognition unit of the biosensor, which was specifically bound to S. aureus. The probe was released from AP and initiated into the subsequent DNA amplification reactions where S. aureus was present, converting the detection of S. aureus to the investigation of probe oligonucleotide. The RCA amplification products contained a G-quadruplex motif and formed a three dimensional structure in presence of hemin. The G4/hemin complex showed horseradish peroxidase (HRP)-mimic activity and catalyzed the chemiluminescence reaction of luminol mediated by H 2 O 2 . The results showed that the established biosensor could detect S. aureus specifically with a good linear correlation at 5-10 4  CFU/mL. The signal values based on NEAR-RCA two-step cycle were boosted acutely, much higher than that relied on one-cycle magnification. The limit of detection (LoD) was determined to be as low as 5 CFU/mL. The established aptasensor exhibited a good discrimination of living against dead S. aureus, and can be applied to detect S. aureus in the food industry. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Detection of short repeated genomic sequences on metaphase chromosomes using padlock probes and target primed rolling circle DNA synthesis

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    Stougaard Magnus

    2007-11-01

    Full Text Available Abstract Background In situ detection of short sequence elements in genomic DNA requires short probes with high molecular resolution and powerful specific signal amplification. Padlock probes can differentiate single base variations. Ligated padlock probes can be amplified in situ by rolling circle DNA synthesis and detected by fluorescence microscopy, thus enhancing PRINS type reactions, where localized DNA synthesis reports on the position of hybridization targets, to potentially reveal the binding of single oligonucleotide-size probe molecules. Such a system has been presented for the detection of mitochondrial DNA in fixed cells, whereas attempts to apply rolling circle detection to metaphase chromosomes have previously failed, according to the literature. Methods Synchronized cultured cells were fixed with methanol/acetic acid to prepare chromosome spreads in teflon-coated diagnostic well-slides. Apart from the slide format and the chromosome spreading everything was done essentially according to standard protocols. Hybridization targets were detected in situ with padlock probes, which were ligated and amplified using target primed rolling circle DNA synthesis, and detected by fluorescence labeling. Results An optimized protocol for the spreading of condensed metaphase chromosomes in teflon-coated diagnostic well-slides was developed. Applying this protocol we generated specimens for target primed rolling circle DNA synthesis of padlock probes recognizing a 40 nucleotide sequence in the male specific repetitive satellite I sequence (DYZ1 on the Y-chromosome and a 32 nucleotide sequence in the repetitive kringle IV domain in the apolipoprotein(a gene positioned on the long arm of chromosome 6. These targets were detected with good efficiency, but the efficiency on other target sites was unsatisfactory. Conclusion Our aim was to test the applicability of the method used on mitochondrial DNA to the analysis of nuclear genomes, in particular as

  2. Rapid identification of emerging human-pathogenic Sporothrix species with rolling circle amplification

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    Anderson Messias Rodrigues

    2015-12-01

    Full Text Available Sporothrix infections are emerging as an important human and animal threat among otherwise healthy patients, especially in Brazil and China. Correct identification of sporotrichosis agents is beneficial for epidemiological surveillance, enabling implementation of adequate public-health policies and guiding antifungal therapy. In areas of limited resources where sporotrichosis is endemic, high-throughput detection methods that are specific and sensitive are preferred over phenotypic methods that usually result in misidentification of closely related Sporothrix species. We sought to establish rolling circle amplification (RCA as a low-cost screening tool for species-specific identification of human-pathogenic Sporothrix. We developed six species-specific padlock probes targeting polymorphisms in the gene encoding calmodulin. BLAST-searches revealed candidate probes that were conserved intraspecifically; no significant homology with sequences from humans, mice, plants or microorganisms outside members of Sporothrix were found. The accuracy of our RCA-based assay was demonstrated through the specificity of probe-template binding to 25 S. brasiliensis, 58 S. schenckii, 5 S. globosa, 1 S. luriei, 4 S. mexicana, and 3 S. pallida samples. No cross reactivity between closely related species was evident in vitro, and padlock probes yielded 100% specificity and sensitivity down to 3 x 10 6 copies of the target sequence. RCA-based speciation matched identifications via phylogenetic analysis of the gene encoding calmodulin and the rDNA operon (kappa 1.0; 95% confidence interval 1.0-1.0, supporting its use as a reliable alternative to DNA sequencing. This method is a powerful tool for rapid identification and specific detection of medically relevant Sporothrix, and due to its robustness has potential for ecological studies.

  3. Specific functions of the Rep and Rep' proteins of porcine circovirus during copy-release and rolling-circle DNA replication

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    The roles of two porcine circovirus replication initiator proteins, Rep and Rep', in generating copy-release and rolling-circle DNA replication intermediates were determined. Rep uses the supercoiled closed-circular genome (ccc) to initiate leading-strand synthesis (identical to copy-release replica...

  4. Sensor Systems with Magnetic and Optomagnetic Readout of Rolling Circle Amplification Products

    DEFF Research Database (Denmark)

    Hansen, Mikkel Fougt; Donolato, Marco; Fock, Jeppe

    2016-01-01

    We are developing robust biosensors for homogeneous detection of rolling cirle amplification (RCA) products with magnetic and/or optomagnetic readouts based on surface-functionalized magnetic nanoparticles. Binding of RCA amplicons to nanoparticles modifies their ability to rotate in response...... to an applied oscillating magnetic field. As a result, magnetic or optical measurements of these changes in the rotational response of nanoparticles vs. frequency of the magnetic field can be used to quantitate the number of amplicons, and, hence, the concentration of target nucleic acid analytes. After...

  5. Rapid detection of ERG11 gene mutations in clinical Candida albicans isolates with reduced susceptibility to fluconazole by rolling circle amplification and DNA sequencing

    OpenAIRE

    Wang, Huiping; Kong, Fanrong; Sorrell, Tania C; Wang, Bin; McNicholas, Paul; Pantarat, Namfon; Ellis, David; Xiao, Meng; Widmer, Fred; Chen, Sharon CA

    2009-01-01

    Abstract Background Amino acid substitutions in the target enzyme Erg11p of azole antifungals contribute to clinically-relevant azole resistance in Candida albicans. A simple molecular method for rapid detection of ERG11 gene mutations would be an advantage as a screening tool to identify potentially-resistant strains and to track their movement. To complement DNA sequencing, we developed a padlock probe and rolling circle amplification (RCA)-based method to detect a series of mutations in th...

  6. A cascade amplification strategy based on rolling circle amplification and hydroxylamine amplified gold nanoparticles enables chemiluminescence detection of adenosine triphosphate.

    Science.gov (United States)

    Wang, Ping; Zhang, Tonghuan; Yang, Taoyi; Jin, Nan; Zhao, Yanjun; Fan, Aiping

    2014-08-07

    A highly sensitive and selective chemiluminescent (CL) biosensor for adenosine triphosphate (ATP) was developed by taking advantage of the ATP-dependent enzymatic reaction (ATP-DER), the powerful signal amplification capability of rolling circle amplification (RCA), and hydroxylamine-amplified gold nanoparticles (Au NPs). The strategy relies on the ability of ATP, a cofactor of T4 DNA ligase, to trigger the ligation-RCA reaction. In the presence of ATP, the T4 DNA ligase catalyzes the ligation reaction between the two ends of the padlock probe, producing a closed circular DNA template that initiates the RCA reaction with phi29 DNA polymerase and dNTP. Therein, many complementary copies of the circular template can be generated. The ATP-DER is eventually converted into a detectable CL signal after a series of processes, including gold probe hybridization, hydroxylamine amplification, and oxidative gold metal dissolution coupled with a simple and sensitive luminol CL reaction. The CL signal is directly proportional to the ATP level. The results showed that the detection limit of the assay is 100 pM of ATP, which compares favorably with those of other ATP detection techniques. In addition, by taking advantage of ATP-DER, the proposed CL sensing system exhibits extraordinary specificity towards ATP and could distinguish the target molecule ATP from its analogues. The proposed method provides a new and versatile platform for the design of novel DNA ligation reaction-based CL sensing systems for other cofactors. This novel ATP-DER based CL sensing system may find wide applications in clinical diagnosis as well as in environmental and biomedical fields.

  7. A novel electrochemical sensing strategy for rapid and ultrasensitive detection of Salmonella by rolling circle amplification and DNA–AuNPs probe

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Dan; Yan, Yurong; Lei, Pinhua; Shen, Bo [Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016 (China); Cheng, Wei [Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016 (China); The Center for Clinical Molecular Medical detection, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Ju, Huangxian [Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016 (China); State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China); Ding, Shijia, E-mail: dingshijia@163.com [Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016 (China)

    2014-10-10

    A novel electrochemical sensing strategy was developed for ultrasensitive and rapid detection of Salmonella by combining the rolling circle amplification with DNA–AuNPs probe. - Highlights: • This paper presented a novel sensing strategy for the rapid and ultrasensitive detection for Salmonella. • Combination of rolling circle amplification and DNA–AuNPs probe is the first time for Salmonella electrochemical detection. • The method displayed excellent sensitivity and specificity for detection of Salmonella. • The fabricated biosensor was successfully applied to detect Salmonella in milk samples. - Abstract: A novel electrochemical sensing strategy was developed for ultrasensitive and rapid detection of Salmonella by combining the rolling circle amplification with DNA–AuNPs probe. The target DNA could be specifically captured by probe 1 on the sensing interface. Then the circularization mixture was added to form a typical sandwich structure. In the presence of dNTPs and phi29 DNA polymerase, the RCA was initiated to produce micrometer-long single-strand DNA. Finally, the detection probe (DNA–AuNPs) could recognize RCA product to produce enzymatic electrochemical signal. Under optimal conditions, the calibration curve of synthetic target DNA had good linearity from 10 aM to 10 pM with a detection limit of 6.76 aM (S/N = 3). The developed method had been successfully applied to detect Salmonella as low as 6 CFU mL{sup −1} in real milk sample. This proposed strategy showed great potential for clinical diagnosis, food safety and environmental monitoring.

  8. A novel electrochemical sensing strategy for rapid and ultrasensitive detection of Salmonella by rolling circle amplification and DNA–AuNPs probe

    International Nuclear Information System (INIS)

    Zhu, Dan; Yan, Yurong; Lei, Pinhua; Shen, Bo; Cheng, Wei; Ju, Huangxian; Ding, Shijia

    2014-01-01

    A novel electrochemical sensing strategy was developed for ultrasensitive and rapid detection of Salmonella by combining the rolling circle amplification with DNA–AuNPs probe. - Highlights: • This paper presented a novel sensing strategy for the rapid and ultrasensitive detection for Salmonella. • Combination of rolling circle amplification and DNA–AuNPs probe is the first time for Salmonella electrochemical detection. • The method displayed excellent sensitivity and specificity for detection of Salmonella. • The fabricated biosensor was successfully applied to detect Salmonella in milk samples. - Abstract: A novel electrochemical sensing strategy was developed for ultrasensitive and rapid detection of Salmonella by combining the rolling circle amplification with DNA–AuNPs probe. The target DNA could be specifically captured by probe 1 on the sensing interface. Then the circularization mixture was added to form a typical sandwich structure. In the presence of dNTPs and phi29 DNA polymerase, the RCA was initiated to produce micrometer-long single-strand DNA. Finally, the detection probe (DNA–AuNPs) could recognize RCA product to produce enzymatic electrochemical signal. Under optimal conditions, the calibration curve of synthetic target DNA had good linearity from 10 aM to 10 pM with a detection limit of 6.76 aM (S/N = 3). The developed method had been successfully applied to detect Salmonella as low as 6 CFU mL −1 in real milk sample. This proposed strategy showed great potential for clinical diagnosis, food safety and environmental monitoring

  9. Antigen retrieval, blocking, detection and visualisation systems in immunohistochemistry: a review and practical evaluation of tyramide and rolling circle amplification systems.

    Science.gov (United States)

    Warford, Anthony; Akbar, Hameed; Riberio, Deise

    2014-11-01

    To achieve specificity and sensitivity using immunohistochemistry it is necessary to combine the application of validated primary antibodies with optimised pre-treatment, detection and visualisation steps. The influence of these surrounding procedures is reviewed. A practical evaluation of tyramide signal amplification and rolling circle amplification detection methods is provided in which formalin fixed paraffin embedded sections of adenocarcinomas of breast, colon and lung together with squamous metaplasia of lung were immunostained with CD20 and CK19 primary antibodies. The results indicate that the detection systems are of comparable sensitivity and specificity. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Voltammetric determination of attomolar levels of a sequence derived from the genom of hepatitis B virus by using molecular beacon mediated circular strand displacement and rolling circle amplification.

    Science.gov (United States)

    Huang, Shan; Feng, Mengmeng; Li, Jiawen; Liu, Yi; Xiao, Qi

    2018-03-03

    The authors describe an electrochemical method for the determination of the single-stranded DNA (ssDNA) oligonucleotide with a sequence derived from the genom of hepatitis B virus (HBV). It is making use of circular strand displacement (CSD) and rolling circle amplification (RCA) strategies mediated by a molecular beacon (MB). This ssDNA hybridizes with the loop portion of the MB immobilized on the surface of a gold electrode, while primer DNA also hybridizes with the rest of partial DNA sequences of MB. This triggers the MB-mediated CSD. The RCA is then initiated to produce a long DNA strand with multiple tandem-repeat sequences, and this results in a significant increase of the differential pulse voltammetric response of the electrochemical probe Methylene Blue at a rather low working potential of -0.24 V (vs. Ag/AgCl). Under optimal experimental conditions, the assay displays an ultrahigh sensitivity (with a 2.6 aM detection limit) and excellent selectivity. Response is linear in the 10 to 700 aM DNA concentration range. Graphical abstract Schematic of a voltammetric method for the determination of attomolar levels of target DNA. It is based on molecular beacon mediated circular strand displacement and rolling circle amplification strategies. Under optimal experimental conditions, the assay displays an ultrahigh sensitivity with a 2.6 aM detection limit and excellent selectivity.

  11. Specific functions of the Rep and Rep׳ proteins of porcine circovirus during copy-release and rolling-circle DNA replication.

    Science.gov (United States)

    Cheung, Andrew K

    2015-07-01

    The roles of two porcine circovirus replication initiator proteins, Rep and Rep׳, in generating copy-release and rolling-circle DNA replication intermediates were determined. Rep uses the supercoiled closed-circular genome (ccc) to initiate leading-strand synthesis (identical to copy-release replication) and generates the single-stranded circular (ssc) genome from the displaced DNA strand. In the process, a minus-genome primer (MGP) necessary for complementary-strand synthesis, from ssc to ccc, is synthesized. Rep׳ cleaves the growing nascent-strand to regenerate the parent ccc molecule. In the process, a Rep׳-DNA hybrid containing the right palindromic sequence (at the origin of DNA replication) is generated. Analysis of the virus particle showed that it is composed of four components: ssc, MGP, capsid protein and a novel Rep-related protein (designated Protein-3). Copyright © 2015. Published by Elsevier Inc.

  12. Using Quality Circles to Enhance Student Involvement and Course Quality in a Large Undergraduate Food Science and Human Nutrition Course

    Science.gov (United States)

    Schmidt, S. J.; Parmer, M. S.; Bohn, D. M.

    2005-01-01

    Large undergraduate classes are a challenge to manage, to engage, and to assess, yet such formidable classes can flourish when student participation is facilitated. One method of generating authentic student involvement is implementation of quality circles by means of a Student Feedback Committee (SFC), which is a volunteer problem-solving and…

  13. Rolling circle amplification-based analysis of Sri Lankan cassava mosaic virus isolates from Tamil Nadu, India, suggests a low level of genetic variability.

    Science.gov (United States)

    Kushawaha, Akhilesh Kumar; Rabindran, Ramalingam; Dasgupta, Indranil

    2018-03-01

    Cassava mosaic disease is a widespread disease of cassava in south Asia and the African continent. In India, CMD is known to be caused by two single-stranded DNA viruses (geminiviruses), Indian cassava mosaic virus (ICMV) and Sri Lankan cassava mosdaic virus (SLCMV). Previously, the diversity of ICMV and SLCMV in India has been studied using PCR, a sequence-dependent method. To have a more in-depth study of the variability of the above viruses and to detect any novel geminiviruses associated with CMD, sequence-independent amplification using rolling circle amplification (RCA)-based methods were used. CMD affected cassava plants were sampled across eighty locations in nine districts of the southern Indian state of Tamil Nadu. Twelve complete sequence of coat protein genes of the resident geminiviruses, comprising 256 amino acid residues were generated from the above samples, which indicated changes at only six positions. RCA followed by RFLP of the 80 samples indicated that most samples (47) contained only SLCMV, followed by 8, which were infected jointly with ICMV and SLCMV. In 11 samples, the pattern did not match the expected patterns from either of the two viruses and hence, were variants. Sequence analysis of an average of 700 nucleotides from 31 RCA-generated fragments of the variants indicated identities of 97-99% with the sequence of a previously reported infectious clone of SLCMV. The evidence suggests low levels of genetic variability in the begomoviruses infecting cassava, mainly in the form of scattered single nucleotide changes.

  14. Identification, characterization and preliminary X-ray diffraction analysis of the rolling-circle replication initiator protein from plasmid pSTK1

    International Nuclear Information System (INIS)

    Carr, Stephen B.; Mecia, Lauren B.; Phillips, Simon E. V.; Thomas, Christopher D.

    2013-01-01

    A proteolytically stable fragment of a plasmid replication initiation protein from the thermophile G. stearothermophilus has been biochemically characterized, crystallized and diffraction data collected to a resolution of 2.5 Å. Antibiotic resistance in bacterial pathogens poses an ever-increasing risk to human health. In antibiotic-resistant strains of Staphylococcus aureus this resistance often resides in extra-chromosomal plasmids, such as those of the pT181 family, which replicate via a rolling-circle mechanism mediated by a plasmid-encoded replication initiation protein. Currently, there is no structural information available for the pT181-family Rep proteins. Here, the crystallization of a catalytically active fragment of a homologous replication initiation protein from the thermophile Geobacillus stearothermophilus responsible for the replication of plasmid pSTK1 is reported. Crystals of the RepSTK1 fragment diffracted to a resolution of 2.5 Å and belonged to space group P2 1 2 1 2 1

  15. Homogeneous and label-free detection of microRNAs using bifunctional strand displacement amplification-mediated hyperbranched rolling circle amplification.

    Science.gov (United States)

    Zhang, Li-rong; Zhu, Guichi; Zhang, Chun-yang

    2014-07-01

    MicroRNAs (miRNAs) are an emerging class of biomarkers and therapeutic targets for various diseases including cancers. Here, we develop a homogeneous and label-free method for sensitive detection of let-7a miRNA based on bifunctional strand displacement amplification (SDA)-mediated hyperbranched rolling circle amplification (HRCA). The binding of target miRNA with the linear template initiates the bifunctional SDA reaction, generating two different kinds of triggers which can hybridize with the linear template to initiate new rounds of SDA reaction for the production of more and more triggers. In the meantime, the released two different kinds of triggers can function as the first and the second primers, respectively, to initiate the HRCA reaction whose products can be simply monitored by a standard fluorometer with SYBR Green I as the fluorescent indicator. The proposed method exhibits high sensitivity with a detection limit of as low as 1.8 × 10(-13) M and a large dynamic range of 5 orders of magnitude from 0.1 pM to 10 nM, and it can even discriminate the single-base difference among the miRNA family members. Moreover, this method can be used to analyze the total RNA samples from the human lung tissues and might be further applied for sensitive detection of various proteins, small molecules, and metal ions in combination with specific aptamers.

  16. The qacC gene has recently spread between rolling circle plasmids of Staphylococcus, indicative of a novel gene transfer mechanism

    Directory of Open Access Journals (Sweden)

    Trudy M. Wassenaar

    2016-09-01

    Full Text Available Resistance of Staphylococcus species to quaternary ammonium compounds, frequently used as disinfectants and biocides, can be attributed to qac genes. These qac gene products belong to the Small Multidrug Resistant (SMR protein family, and are often encoded by rolling-circle (RC replicating plasmids. Four classes of SMR-type qac gene families have been described in Staphylococcus species: qacC, qacG, qacJ and qacH. Within their class, these genes are highly conserved, but qacC genes are extremely conserved, although they are found in variable plasmid backgrounds. The lower degree of sequence identity of these plasmids compared to the strict nucleotide conservation of their qacC means that this gene has recently spread. In the absence of insertion sequences or other genetic elements explaining the mobility, we sought for an explanation of mobilization by sequence comparison. Publically available sequences of qac genes, their flanking genes and the replication gene that is invariably present in RC-plasmids were compared to reconstruct the evolutionary history of these plasmids and to explain the recent spread of qacC. Here we propose a new model that explains how qacC is mobilized and transferred to acceptor RC-plasmids without assistance of other genes, by means of its location in between the Double Strand replication Origin (DSO and the Single-Strand replication Origin (SSO. The proposed mobilization model of this DSO-qacC-SSO element represents a novel mechanism of gene mobilization in RC-plasmids, which has also been employed by other genes, such as lnuA (conferring lincomycin resistance. The proposed gene mobility has aided to the wide spread of clinically relevant resistance genes in Staphylococcus populations.

  17. An "off-on" electrochemiluminescent biosensor based on DNAzyme-assisted target recycling and rolling circle amplifications for ultrasensitive detection of microRNA.

    Science.gov (United States)

    Zhang, Pu; Wu, Xiaoyan; Yuan, Ruo; Chai, Yaqin

    2015-03-17

    In this study, an off-on switching of a dual amplified electrochemiluminescence (ECL) biosensor based on Pb(2+)-induced DNAzyme-assisted target recycling and rolling circle amplification (RCA) was constructed for microRNA (miRNA) detection. First, the primer probe with assistant probe and miRNA formed Y junction which was cleaved with the addition of Pb(2+) to release miRNA. Subsequently, the released miRNA could initiate the next recycling process, leading to the generation of numerous intermediate DNA sequences (S2). Afterward, bare glassy carbon electrode (GCE) was immersed into HAuCl4 solution to electrodeposit a Au nanoparticle layer (depAu), followed by the assembly of a hairpin probe (HP). Then, dopamine (DA)-modified DNA sequence (S1) was employed to hybridize with HP, which switching off the sensing system. This is the first work that employs DA to quench luminol ECL signal, possessing the biosensor ultralow background signal. Afterward, S2 produced by the target recycling process was loaded onto the prepared electrode to displace S1 and served as an initiator for RCA. With rational design, numerous repeated DNA sequences coupling with hemin to form hemin/G-quadruplex were generated, which could exhibit strongly catalytic toward H2O2, thus amplified the ECL signal and switched the ON state of the sensing system. The liner range for miRNA detection was from 1.0 fM to 100 pM with a low detection limit down to 0.3 fM. Moreover, with the high sensitivity and specificity induced by the dual signal amplification, the proposed miRNA biosensor holds great potential for analysis of other interesting tumor markers.

  18. Real-time monitoring of mycobacterium genomic DNA with target-primed rolling circle amplification by a Au nanoparticle-embedded SPR biosensor.

    Science.gov (United States)

    Xiang, Yang; Zhu, Xiaoyan; Huang, Qing; Zheng, Junsong; Fu, Weiling

    2015-04-15

    In this study, we developed a surface plasmon resonance (SPR) DNA biosensor array based on target-primed rolling circle amplification (RCA) for isothermal and rapid detection of two pathogenic mycobacteria, Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium complex (MAC).The species-specific padlock probe (PLP) was designed to target the sequence in 16S-23S rRNA gene internal transcribed spacer (ITS). After ligation, the circularized PLP could be primed by the target sequence to initial RCA. The RCA performed simultaneously with the cleavage reaction to produce small fragments of single strand DNA which immediately hybridized with the probe immobilized on the sensor chip without denaturation. This process caused SPR angle changes on the chip surface, which made the detection for analysis from the solution achievable, and dynamic real-time RCA monitoring of mycobacterium possible. Besides, Au nanoparticles (AuNPs) were directly assembled onto the surface of the sensor chip via hexanedithiol (HDT) for the enhancement of sensitivity as a label-free detection system. Experimental results show that the signal enhancement by the target-primed RCA together with AuNPs-embedded surface caused at least10-fold increased sensitivity as compared with conventional RCA on bare SPR chip method. Within 40min amplification duration as low as 20amol of synthetic targets and 10(4)CFUmL(-1) of genomic DNA from clinical samples can be detected. The proposed method not only provides a simple design idea for liquid-phase amplification monitoring, but also apply it in clinical pathogen detection, which holds great promise in ultrasensitive bioassay in the future. Copyright © 2014. Published by Elsevier B.V.

  19. A Label-Free and Sensitive Fluorescent Qualitative Assay for Bisphenol A Based on Rolling Circle Amplification/Exonuclease III-Combined Cascade Amplification.

    Science.gov (United States)

    Li, Xia; Song, Juan; Xue, Qing-Wang; You, Fu-Heng; Lu, Xia; Kong, Yan-Cong; Ma, Shu-Yi; Jiang, Wei; Li, Chen-Zhong

    2016-10-21

    Bisphenol A (BPA) detection in drinking water and food packaging materials has attracted much attention since the discovery that BPA can interfere with normal physiological processes and cause adverse health effects. Here, we constructed a label-free aptamer fluorescent assay for selective and sensitive detection of BPA based on the rolling circle amplification (RCA)/Exonuclease III (Exo III)-combined cascade amplification strategy. First, the duplex DNA probe (RP) with anti-BPA aptamer and trigger sequence was designed for BPA recognition and signal amplification. Next, under the action of BPA, the trigger probe was liberated from RP to initiate RCA reaction as primary amplification. Subsequently, the RCA products were used to trigger Exo III assisted secondary amplification with the help of hairpin probes, producing plenty of "G-quadruplex" in lantern-like structures. Finally, the continuously enriched "G-quadruplex lanterns" were lightened by zinc(II)-protoporphyrin IX (ZnPPIX) generating enhanced fluorescence signals. By integrating the primary RCA and secondary Exo III mediated cascade amplification strategy, this method displayed an excellent sensitivity with the detection limits of 5.4 × 10 -17 M. In addition, the anti-BPA aptamer exhibits high recognition ability with BPA, guaranteeing the specificity of detection. The reporter signal probe (G-quadruplex with ZnPPIX) provides a label-free fluorescence signals readout without complicated labeling procedures, making the method simple in design and cost-effective in operation. Moreover, environmental samples analysis was also performed, suggesting that our strategy was reliable and had a great potential application in environmental monitoring.

  20. A Label-Free and Sensitive Fluorescent Qualitative Assay for Bisphenol A Based on Rolling Circle Amplification/Exonuclease III-Combined Cascade Amplification

    Directory of Open Access Journals (Sweden)

    Xia Li

    2016-10-01

    Full Text Available Bisphenol A (BPA detection in drinking water and food packaging materials has attracted much attention since the discovery that BPA can interfere with normal physiological processes and cause adverse health effects. Here, we constructed a label-free aptamer fluorescent assay for selective and sensitive detection of BPA based on the rolling circle amplification (RCA/Exonuclease III (Exo III-combined cascade amplification strategy. First, the duplex DNA probe (RP with anti-BPA aptamer and trigger sequence was designed for BPA recognition and signal amplification. Next, under the action of BPA, the trigger probe was liberated from RP to initiate RCA reaction as primary amplification. Subsequently, the RCA products were used to trigger Exo III assisted secondary amplification with the help of hairpin probes, producing plenty of “G-quadruplex” in lantern-like structures. Finally, the continuously enriched “G-quadruplex lanterns” were lightened by zinc(II-protoporphyrin IX (ZnPPIX generating enhanced fluorescence signals. By integrating the primary RCA and secondary Exo III mediated cascade amplification strategy, this method displayed an excellent sensitivity with the detection limits of 5.4 × 10−17 M. In addition, the anti-BPA aptamer exhibits high recognition ability with BPA, guaranteeing the specificity of detection. The reporter signal probe (G-quadruplex with ZnPPIX provides a label-free fluorescence signals readout without complicated labeling procedures, making the method simple in design and cost-effective in operation. Moreover, environmental samples analysis was also performed, suggesting that our strategy was reliable and had a great potential application in environmental monitoring.

  1. Rapid detection of ERG11 gene mutations in clinical Candida albicans isolates with reduced susceptibility to fluconazole by rolling circle amplification and DNA sequencing

    Directory of Open Access Journals (Sweden)

    Ellis David

    2009-08-01

    Full Text Available Abstract Background Amino acid substitutions in the target enzyme Erg11p of azole antifungals contribute to clinically-relevant azole resistance in Candida albicans. A simple molecular method for rapid detection of ERG11 gene mutations would be an advantage as a screening tool to identify potentially-resistant strains and to track their movement. To complement DNA sequencing, we developed a padlock probe and rolling circle amplification (RCA-based method to detect a series of mutations in the C. albicans ERG11 gene using "reference" azole-resistant isolates with known mutations. The method was then used to estimate the frequency of ERG11 mutations and their type in 25 Australian clinical C. albicans isolates with reduced susceptibility to fluconazole and in 23 fluconazole-susceptible isolates. RCA results were compared DNA sequencing. Results The RCA assay correctly identified all ERG11 mutations in eight "reference" C. albicans isolates. When applied to 48 test strains, the RCA method showed 100% agreement with DNA sequencing where an ERG11 mutation-specific probe was used. Of 20 different missense mutations detected by sequencing in 24 of 25 (96% isolates with reduced fluconazole susceptibility, 16 were detected by RCA. Five missense mutations were detected by both methods in 18 of 23 (78% fluconazole-susceptible strains. DNA sequencing revealed that mutations in non-susceptible isolates were all due to homozygous nucleotide changes. With the exception of the mutations leading to amino acid substitution E266D, those in fluconazole-susceptible strains were heterozygous. Amino acid substitutions common to both sets of isolates were D116E, E266D, K128T, V437I and V488I. Substitutions unique to isolates with reduced fluconazole susceptibility were G464 S (n = 4 isolates, G448E (n = 3, G307S (n = 3, K143R (n = 3 and Y123H, S405F and R467K (each n = 1. DNA sequencing revealed a novel substitution, G450V, in one isolate. Conclusion The sensitive RCA

  2. Rolling-circle plasmids from Bacillus subtilis : complete nucleotide sequences and analyses of genes of pTA1015, pTA1040, pTA1050 and pTA1060, and comparisons with related plasmids from Gram-positive bacteria

    NARCIS (Netherlands)

    Meijer, W.J.; Schuurs-Wisman, Bea; Terpstra, P; Thorsted, P.; Thomas, C.M.; Holsappel, S; Venema, G; Bron, S

    Most small plasmids of Gram-positive bacteria use the rolling-circle mechanism of replication and several of these have been studied in considerable detail at the DNA level and for the function of their genes. Although most of the common laboratory Bacillus subtilis 168 strains do not contain

  3. Research circles

    DEFF Research Database (Denmark)

    Nordentoft, Helle Merete; Thomsen, Rie; Möller, Jonas

    lifelong guidance policies. This paper presents `research circles´ as a way to develop guidance practices through long-term research relationships between practice and research. Research circles support a bottom up approach to policy development just like ELGPN considers to be necessary and required...... of their habitual pedagogical role and enables them to observe and analyze their own practice. In conclusion, this methodological approach to the development of guidance practices introduces a combination between theory and practice that meets current needs of practice, policy and research....

  4. Domain Discretization and Circle Packings

    DEFF Research Database (Denmark)

    Dias, Kealey

    A circle packing is a configuration of circles which are tangent with one another in a prescribed pattern determined by a combinatorial triangulation, where the configuration fills a planar domain or a two-dimensional surface. The vertices in the triangulation correspond to centers of circles...... to domain discretization problems such as triangulation and unstructured mesh generation techniques. We wish to ask ourselves the question: given a cloud of points in the plane (we restrict ourselves to planar domains), is it possible to construct a circle packing preserving the positions of the vertices...... and constrained meshes having predefined vertices as constraints. A standard method of two-dimensional mesh generation involves conformal mapping of the surface or domain to standardized shapes, such as a disk. Since circle packing is a new technique for constructing discrete conformal mappings, it is possible...

  5. Small circles

    DEFF Research Database (Denmark)

    Ling, Richard; Bjelland, Johannes; Sundsøy, Pål

    2014-01-01

    and spatial movement is highly predictable and that the majority of calls and text messages are sent to only four to six different persons. This article extends this research by examining both tie strength and the distance between the interlocutors in urban and rural settings. The findings show that even......This article examines how we use mobile telephony to maintain our physically and socially closest social circle. The analysis is based on traffic data gathered from Norway using approximately 24 million calls and texts made by private individuals. Previous research has shown that our temporal...... as information and communication technologies (ICTs) potentially put the world at our fingertips, the mobile phone is an instrument of a more limited geographical and social sphere. Approximately two-thirds of our calls/texts go to strong ties that are within a 25-km radius....

  6. Circle diffeomorphisms forced by expanding circle maps

    NARCIS (Netherlands)

    Homburg, A.J.

    2012-01-01

    We discuss the dynamics of skew product maps defined by circle diffeomorphisms forced by expanding circle maps. We construct an open class of such systems that are robustly topologically mixing and for which almost all points in the same fiber converge under iteration. This property follows from the

  7. Exploring Factors That Influence Quality Literature Circles

    Science.gov (United States)

    Young, Chase; Mohr, Kathleen A. J.

    2018-01-01

    Research indicates that literature circles are an authentic means for literacy development that students typically enjoy. To better understand the potential value and to add to the research base regarding literature circles, this study, involving 17 fourth graders, explores factors that may influence the quality of literature discussions,…

  8. General minisum circle location

    DEFF Research Database (Denmark)

    Körner, Mark; Brimberg, Jack; Juel, Henrik

    2009-01-01

    In our paper we approximate a set of given points by a general circle. More precisely, we consider the problem of locating and scaling the unit ball of some given norm k1 with respect to xed points on the plane such that the sum of weighted distances between the circle and the xed points is minim......In our paper we approximate a set of given points by a general circle. More precisely, we consider the problem of locating and scaling the unit ball of some given norm k1 with respect to xed points on the plane such that the sum of weighted distances between the circle and the xed points...

  9. Vicious Circles in Organizations.

    Science.gov (United States)

    Masuch, Michael

    1985-01-01

    After examining some elementary notions of action theory and cybernetics, this article analyzes the dynamics, clustering, and survival chances of vicious circles. It argues that the action perspective implies that many structural suboptimalities of organizations are caused by vicious circles. Eleven figures and 105 references are provided. (DCS)

  10. Polygons and Their Circles

    Science.gov (United States)

    Stephenson, Paul

    2009-01-01

    In order to find its circumference, Archimedes famously boxed the circle between two polygons. Ending the first of a series of articles (MT179) with an aside, Francis Lopez-Real reverses the situation to ask: Which polygons can be boxed between two circles? (The official term for such polygons is "bicentric".) The sides of these polygons are…

  11. The three circle method

    International Nuclear Information System (INIS)

    Garncarek, Z.

    1989-01-01

    The three circle method in its general form is presented. The method is especially useful for investigation of shapes of agglomerations of objects. An example of its applications to investigation of galaxies distribution is given. 17 refs. (author)

  12. The Inner Circle Revisited

    DEFF Research Database (Denmark)

    Grau Larsen, Anton; Ellersgaard, Christoph

    2018-01-01

    in social networks, we identify a cohesive core group of 171 individuals within a corporate elite of 6154 board members of the top 1037 Danish corporations. A high degree of social homogeneity in gender, social background, education and career position underlines the cohesion of the inner circle. By mapping...

  13. Inside Larry's Circle

    Science.gov (United States)

    Arnold, Alice

    2009-01-01

    Last spring, students from several North Carolina middle schools were invited to participate in the annual Celebrate the Arts festival in Columbus Country. Larry Hewett, a local art teacher, had been selected to instruct the middle-school students. Larry's River Rock Circles project was made as the starting point for the Celebrate the Arts…

  14. Dynamics on the Circle

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 11. Dynamics on the Circle - Interval Dynamics and Rotation Number. Siddhartha Gadgil. General Article Volume 8 Issue 11 November 2003 pp 25-36. Fulltext. Click here to view fulltext PDF. Permanent link:

  15. Circles, Materiality and Movement

    Science.gov (United States)

    Chorney, Sean

    2017-01-01

    This paper approaches the concept of the circle through the framework of mathematics-as-becoming. This paper focuses specifically on how a concept can be thought of as a process, and on the implications that this might have for mathematics learning. Contrary to long-standing assumptions about mathematical concepts as ideal, inert, Platonic forms,…

  16. Roll-to-Roll production of carbon nanotubes based supercapacitors

    Science.gov (United States)

    Zhu, Jingyi; Childress, Anthony; Karakaya, Mehmet; Roberts, Mark; Arcilla-Velez, Margarita; Podila, Ramakrishna; Rao, Apparao

    2014-03-01

    Carbon nanomaterials provide an excellent platform for electrochemical double layer capacitors (EDLCs). However, current industrial methods for producing carbon nanotubes are expensive and thereby increase the costs of energy storage to more than 10 Wh/kg. In this regard, we developed a facile roll-to-roll production technology for scalable manufacturing of multi-walled carbon nanotubes (MWNTs) with variable density on run-of-the-mill kitchen Al foils. Our method produces MWNTs with diameter (heights) between 50-100 nm (10-100 μm), and a specific capacitance as high as ~ 100 F/g in non-aqueous electrolytes. In this talk, the fundamental challenges involved in EDLC-suitable MWNT growth, roll-to-roll production, and device manufacturing will be discussed along with electrochemical characteristics of roll-to-roll MWNTs. Research supported by NSF CMMI Grant1246800.

  17. The effect of roll with passive segment on the planetary rolling process

    Directory of Open Access Journals (Sweden)

    Qing-Ling Zeng

    2015-03-01

    Full Text Available In three-roll planetary rolling process, there is secondary torsion phenomenon that may lead to rolling instability. This article proposed a new idea to alleviate the secondary torsion phenomenon by dividing the secondary torsion segment out of the roll as an independent and passive one. To study the performance of the roll with passive segment, the three-dimensional finite element models of planetary rolling process using actual roll or new roll with passive segment involving elastic–plastic and thermal–mechanical coupling were established by the software ABAQUS/Explicit, and a series of analysis had been done successfully. The rolling temperature and rolling force of planetary mill were in good agreement with the measured results, which indicated that the finite element method would supply important reference merit for three-dimensional thermo-mechanical simulation of the three-roll planetary rolling process. Comparing the simulation results of the two models, the results indicated that the change in the roll structure had just a little influence on the metal deformation, temperature, and rolling force, but it lessened the secondary torsion deformation effectively and improved the outside roundness of the rolled tube slightly. The research provided a new idea for the roll design of three-roll planetary mill (PSW.

  18. A game magically circling

    DEFF Research Database (Denmark)

    Ejsing-Duun, Stine

    2011-01-01

    This chapter analyses the relationship between players, the game world, and the ordinary world in alternative reality games (ARGs) and location-based games (LBGs). These games use technology to create a game world in the everyday scene. The topic of this chapter is the concept of the 'magic circle......', which defines the relationship between play and the ordinary world, and how this concept relates to a new kind of game....

  19. Kulturens rolle

    DEFF Research Database (Denmark)

    Hasse, Cathrine

    2007-01-01

    Kulturens rolle. Herunder kulturens betydning for psykologisk teori og forskning set i lyset af den stigende globalisering og væksten i kulturmøder. Der gives eksempler fra hverdagssituationer, den pædagogiske praksis, fra indvandrerforskning, turister men også fra avisernes referater af kulturmø......Kulturens rolle. Herunder kulturens betydning for psykologisk teori og forskning set i lyset af den stigende globalisering og væksten i kulturmøder. Der gives eksempler fra hverdagssituationer, den pædagogiske praksis, fra indvandrerforskning, turister men også fra avisernes referater af...

  20. Hot rolling of thick uranium molybdenum alloys

    Science.gov (United States)

    DeMint, Amy L.; Gooch, Jack G.

    2015-11-17

    Disclosed herein are processes for hot rolling billets of uranium that have been alloyed with about ten weight percent molybdenum to produce cold-rollable sheets that are about one hundred mils thick. In certain embodiments, the billets have a thickness of about 7/8 inch or greater. Disclosed processes typically involve a rolling schedule that includes a light rolling pass and at least one medium rolling pass. Processes may also include reheating the rolling stock and using one or more heavy rolling passes, and may include an annealing step.

  1. Waring's Problem and the Circle Method

    Indian Academy of Sciences (India)

    other interests include classical music and mountaineering. the problems they worked on. Their proof of a slightly. Keywords weaker form of Ramanujan's original formula was pub-. Waring's problem, circle method, ... arc is fairly simple while it is the minor arc estimation that accounts for the 'major' amount of work involved!

  2. Rolling at small scales

    DEFF Research Database (Denmark)

    Nielsen, Kim L.; Niordson, Christian F.; Hutchinson, John W.

    2016-01-01

    The rolling process is widely used in the metal forming industry and has been so for many years. However, the process has attracted renewed interest as it recently has been adapted to very small scales where conventional plasticity theory cannot accurately predict the material response. It is well....... Metals are known to be stronger when large strain gradients appear over a few microns; hence, the forces involved in the rolling process are expected to increase relatively at these smaller scales. In the present numerical analysis, a steady-state modeling technique that enables convergence without...

  3. METHOD OF ROLLING URANIUM

    Science.gov (United States)

    Smith, C.S.

    1959-08-01

    A method is described for rolling uranium metal at relatively low temperatures and under non-oxidizing conditions. The method involves the steps of heating the uranium to 200 deg C in an oil bath, withdrawing the uranium and permitting the oil to drain so that only a thin protective coating remains and rolling the oil coated uranium at a temperature of 200 deg C to give about a 15% reduction in thickness at each pass. The operation may be repeated to accomplish about a 90% reduction without edge cracking, checking or any appreciable increase in brittleness.

  4. Packing circles and spheres on surfaces

    KAUST Repository

    Schiftner, Alexander; Hö binger, Mathias; Wallner, Johannes; Pottmann, Helmut

    2009-01-01

    Inspired by freeform designs in architecture which involve circles and spheres, we introduce a new kind of triangle mesh whose faces' incircles form a packing. As it turns out, such meshes have a rich geometry and allow us to cover surfaces with circle patterns, sphere packings, approximate circle packings, hexagonal meshes which carry a torsion-free support structure, hybrid tri-hex meshes, and others. We show how triangle meshes can be optimized so as to have the incircle packing property. We explain their relation to conformal geometry and implications on solvability of optimization. The examples we give confirm that this kind of meshes is a rich source of geometric structures relevant to architectural geometry. © 2009 ACM.

  5. ENTREPRENEURSHIP EDUCATION AND THE ECONOMY VICIOUS CIRCLES

    Directory of Open Access Journals (Sweden)

    MEDAR LUCIAN ION

    2015-06-01

    Full Text Available Education for sustainable development, involves training honest, active, social and creative persons for ensuring the link between environment, society, economy and politics. Trained entrepreneurs in sustainable development, are the engine system which can bring an economic prosperity. Lack of entrepreneurial education in the last 25 years has led accentuated conditions to avoiding economic development in all reference fields where added value can be achieved. Running away from excessive taxation led to the establishment of vicious circles in the economy. Vicious circles of the economy can be found in saving, tax policy, productive investment and the informal economy. Through this study will present the importance of entrepreneurship education in the real economy and some specifications to exit entrepreneurs from vicious circles of the economy.

  6. Packing circles and spheres on surfaces

    KAUST Repository

    Schiftner, Alexander

    2009-12-01

    Inspired by freeform designs in architecture which involve circles and spheres, we introduce a new kind of triangle mesh whose faces\\' incircles form a packing. As it turns out, such meshes have a rich geometry and allow us to cover surfaces with circle patterns, sphere packings, approximate circle packings, hexagonal meshes which carry a torsion-free support structure, hybrid tri-hex meshes, and others. We show how triangle meshes can be optimized so as to have the incircle packing property. We explain their relation to conformal geometry and implications on solvability of optimization. The examples we give confirm that this kind of meshes is a rich source of geometric structures relevant to architectural geometry.

  7. Packing circles and spheres on surfaces

    KAUST Repository

    Schiftner, Alexander

    2009-01-01

    Inspired by freeform designs in architecture which involve circles and spheres, we introduce a new kind of triangle mesh whose faces\\' incircles form a packing. As it turns out, such meshes have a rich geometry and allow us to cover surfaces with circle patterns, sphere packings, approximate circle packings, hexagonal meshes which carry a torsion-free support structure, hybrid tri-hex meshes, and others. We show how triangle meshes can be optimized so as to have the incircle packing property. We explain their relation to conformal geometry and implications on solvability of optimization. The examples we give confirm that this kind of meshes is a rich source of geometric structures relevant to architectural geometry. © 2009 ACM.

  8. Packing circles and spheres on surfaces

    KAUST Repository

    Schiftner, Alexander; Hö binger, Mathias; Wallner, Johannes; Pottmann, Helmut

    2009-01-01

    Inspired by freeform designs in architecture which involve circles and spheres, we introduce a new kind of triangle mesh whose faces' incircles form a packing. As it turns out, such meshes have a rich geometry and allow us to cover surfaces with circle patterns, sphere packings, approximate circle packings, hexagonal meshes which carry a torsion-free support structure, hybrid tri-hex meshes, and others. We show how triangle meshes can be optimized so as to have the incircle packing property. We explain their relation to conformal geometry and implications on solvability of optimization. The examples we give confirm that this kind of meshes is a rich source of geometric structures relevant to architectural geometry.

  9. Porcine circovirus: transcription and rolling-circle DNA replication

    Science.gov (United States)

    This review summarizes the molecular studies pertaining to porcine circovirus (PCV) transcription and DNA replication. The genome of PCV is circular, single-stranded DNA and contains 1759-1768 nucleotides. Both the genome-strand (packaged in the virus particle) and the complementary-strand (synthesi...

  10. Recumbent Stone Circles

    Science.gov (United States)

    Ruggles, Clive L. N.

    During the 1970s and early 1980s, British archaeoastronomers were striving to bridge the interpretative gulf between the "megalithic observatories" of Alexander Thom and an archaeological mainstream that, generally speaking, was hostile to any mention of astronomy in relation to the megalithic monuments of Neolithic and Early Bronze Age Britain. The Scottish recumbent stone circles (RSCs) came to represent an example where sounder methodology could overcome many of the data selection issues that had beset earlier studies and, with due restraint, produce credible interpretations. Systematic studies of their orientations consistently concluded that the RSCs had a strong lunar connection, and it was widely envisaged that they were the setting for ceremonies associated with the appearance of the moon over the recumbent stone. Other evidence such as the presence of white quartz and the spatial distribution of cupmarks appeared to back up this conclusion. New archaeological investigations since 1999 have challenged and modified these conclusions, confirming in particular that the circles were built to enclose cairns rather than to demarcate open spaces. Yet the restricted pattern of orientations of these structures could only have been achieved by reference to the basic diurnal motions of the skies, and orientation in relation to simple observations of the midsummer moon remains the most likely reading of the alignment evidence taken as a whole. On the other hand, a consideration of the broader context, which includes the nearby Clava cairns, highlights instead the symbolic importance of the sun.

  11. Differential involvement of dopamine D-1 and D-2 receptors in the circling behaviour induced by apomorphine, SK & F 38393, pergolide and LY 171555 in 6-hydroxydopamine-lesioned rats.

    Science.gov (United States)

    Arnt, J; Hyttel, J

    1985-01-01

    The antagonistic effect of dopamine (DA) D-1 and D-2 antagonists against circling behaviour induced by various DA agonists in 6-OHDA-lesioned rats has been investigated. DA D-1/D-2 selectivity of agonists in vitro was measured by the stimulatory effect on DA-sensitive adenylate cyclase in rat striatal homogenates (D-1), the inhibitory effect on electrically-induced release of 3H-DA in rabbit striatal slices (D-2) and the affinity to 3H-piflutixol (D-1) and 3H-spiroperidol (D-2) binding sites in rat striatal membranes. The contralateral circling behaviour induced by the DA D-1 agonist SK & F 38393 was blocked by the DA D-1 antagonist, SCH 23390, and by the mixed DA D-1/D-2 antagonist cis(Z)-flupentixol, but was not influenced by the DA D-2 antagonists spiroperidol and clebopride. In contrast, circling behaviour induced by the preferential DA D-2 agonists pergolide and LY 171555 was blocked by clebopride, spiroperidol, and cis(Z)-flupentixol, but weakly or not influenced by SCH 23390. Apomorphine-induced circling behaviour was blocked by cis(Z)-flupentixol, partially antagonized by SCH 23390 and clebopride but not inhibited by spiroperidol, although the time-course of circling was changed. Combinations of SCH 23390 with spiroperidol or clebopride in low doses completely blocked the effect of apomorphine. These results indicate that DA D-1 and D-2 receptors mediate circling behaviour through separate mechanisms which can be independently manipulated with respective agonists and antagonists.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. CIRCLE Enhancement After Myopic SMILE.

    Science.gov (United States)

    Siedlecki, Jakob; Luft, Nikolaus; Mayer, Wolfgang J; Siedlecki, Martin; Kook, Daniel; Meyer, Bertram; Bechmann, Martin; Wiltfang, Rainer; Priglinger, Siegfried G; Dirisamer, Martin

    2018-05-01

    To report the outcomes of enhancement after small incision lenticule extraction (SMILE) using the VisuMax CIRCLE option (Carl Zeiss Meditec AG, Jena, Germany), which converts the SMILE cap into a femtosecond LASIK flap for secondary excimer laser application. Of 2,065 SMILE procedures, 22 eyes (1.1%) re-treated with CIRCLE with a follow-up of 3 months were included in the analysis. SMILE was performed in the usual manner. For re-treatment, the CIRCLE procedure was performed with pattern D flap creation on the VisuMax system and subsequent excimer laser ablation with a Zeiss MEL 90 laser (Carl Zeiss Meditec) with plano target in all cases. Spherical equivalent was -5.56 ± 2.22 diopters (D) before SMILE and -0.51 ± 1.08 D before CIRCLE. CIRCLE enhancement was performed after a mean of 10.0 ± 7.9 months, allowed for safe flap lifting in all eyes, and resulted in a final manifest refraction spherical equivalent of 0.18 ± 0.31 D at 3 months (P line of UDVA. Corrected distance visual acuity (CDVA) remained unchanged at all time points (before vs after CIRCLE, P = .40). Two eyes (9.1 %) lost one line of CDVA; no eye lost two or more lines. The safety and efficacy indices were 1.03 and 0.97 at 3 months. The CIRCLE procedure represents an effective re-treatment option after SMILE. Compared to surface ablation re-treatment after SMILE, CIRCLE seems to offer advantages in respect to speed of visual recovery, safety, and predictability, but at the price of flap creation. [J Refract Surg. 2018;34(5):304-309.]. Copyright 2018, SLACK Incorporated.

  13. New Numerical Solution of von Karman Equation of Lengthwise Rolling

    Directory of Open Access Journals (Sweden)

    Rudolf Pernis

    2015-01-01

    Full Text Available The calculation of average material contact pressure to rolls base on mathematical theory of rolling process given by Karman equation was solved by many authors. The solutions reported by authors are used simplifications for solution of Karman equation. The simplifications are based on two cases for approximation of the circular arch: (a by polygonal curve and (b by parabola. The contribution of the present paper for solution of two-dimensional differential equation of rolling is based on description of the circular arch by equation of a circle. The new term relative stress as nondimensional variable was defined. The result from derived mathematical models can be calculated following variables: normal contact stress distribution, front and back tensions, angle of neutral point, coefficient of the arm of rolling force, rolling force, and rolling torque during rolling process. Laboratory cold rolled experiment of CuZn30 brass material was performed. Work hardening during brass processing was calculated. Comparison of theoretical values of normal contact stress with values of normal contact stress obtained from cold rolling experiment was performed. The calculations were not concluded with roll flattening.

  14. Manufacturing Demonstration Facility: Roll-to-Roll Processing

    Energy Technology Data Exchange (ETDEWEB)

    Datskos, Panos G [ORNL; Joshi, Pooran C [ORNL; List III, Frederick Alyious [ORNL; Duty, Chad E [ORNL; Armstrong, Beth L [ORNL; Ivanov, Ilia N [ORNL; Jacobs, Christopher B [ORNL; Graham, David E [ORNL; Moon, Ji Won [ORNL

    2015-08-01

    This Manufacturing Demonstration Facility (MDF)e roll-to-roll processing effort described in this report provided an excellent opportunity to investigate a number of advanced manufacturing approaches to achieve a path for low cost devices and sensors. Critical to this effort is the ability to deposit thin films at low temperatures using nanomaterials derived from nanofermentation. The overarching goal of this project was to develop roll-to-roll manufacturing processes of thin film deposition on low-cost flexible substrates for electronics and sensor applications. This project utilized ORNL s unique Pulse Thermal Processing (PTP) technologies coupled with non-vacuum low temperature deposition techniques, ORNL s clean room facility, slot dye coating, drop casting, spin coating, screen printing and several other equipment including a Dimatix ink jet printer and a large-scale Kyocera ink jet printer. The roll-to-roll processing project had three main tasks: 1) develop and demonstrate zinc-Zn based opto-electronic sensors using low cost nanoparticulate structures manufactured in a related MDF Project using nanofermentation techniques, 2) evaluate the use of silver based conductive inks developed by project partner NovaCentrix for electronic device fabrication, and 3) demonstrate a suite of low cost printed sensors developed using non-vacuum deposition techniques which involved the integration of metal and semiconductor layers to establish a diverse sensor platform technology.

  15. Models to support students’ understanding of measuring area of circles

    Science.gov (United States)

    Rejeki, S.; Putri, R. I. I.

    2018-01-01

    Many studies showed that enormous students got confused about the concepts of measuring area of circles. The main reason is because mathematics classroom practices emphasized on memorizing formulas rather than understanding concepts. Therefore, in this study, a set of learning activities were designed as an innovation in learning area measurement of circles. The activities involved two models namely grid paper and reshaping which are respectively as a means and a strategy to support students’ learning of area measurement of circles. Design research was used as the research approach to achieve the aim. Thirty-eight of 8th graders in Indonesia were involved in this study. In this study, together with the contextual problems, the grid paper and reshaping sectors, which used as the models in this learning, helped the students to gradually develop their understanding of the area measurement of circles. The grid papers plays important role in comparing and estimating areas. Whereas, the reshaping sectors might support students’ understanding of the circumference and the area measurement of circles. Those two models could be the tool for promoting the informal theory of area measurement. Besides, the whole activities gave important role on distinguishing the area and perimeter of circles.

  16. Quality Circles and nuclear energy

    International Nuclear Information System (INIS)

    Wiesendanger, J.; Raveleau, G.

    1983-01-01

    A Circle of Quality is a small group of workers or employees made up of from five to ten volunteers from a given shop, office, or factory team, or sharing identical concerns. For every problem that is taken under advisement, these groups draft a solution, test its validity and propose its application, eventually monitoring its implementation and assessing the results achieved. The problems dealt with and the improvements introduced frequently concern details of the personnel's work routines, product quality, tool reliability. But these improvements become so numerous that, eventually, it is the efficiency of an entire office, shop, department or plant, and hence that of the company itself, that is enhanced thereby. Some of the features of a circle of quality are given. A Circle of quality is a contribution to the reliability of the individual, as also to innovation [fr

  17. 2. A Circle of ideas

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 2. Geometry A Circle of Ideas. Kapil H Paranjape. Series Article Volume 1 Issue 2 February 1996 pp 26-31. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/001/02/0026-0031. Author Affiliations.

  18. On a Family of Circles

    Science.gov (United States)

    Feeman, Timothy G.

    2011-01-01

    We generalize a standard example from precalculus and calculus texts to give a simple description in polar coordinates of any circle that passes through the origin. We discuss an occurrence of this formula in the context of medical imaging. (Contains 1 figure.)

  19. Queuing systems on a circle

    NARCIS (Netherlands)

    Kroese, Dirk; Schmidt, Volker

    1993-01-01

    Consider a ring on which customers arrive according to a Poisson process. Arriving customers drop somewhere on the circle and wait there for a server who travels on the ring. Whenever this server encounters a customer, he stops and serves the customer according to an arbitrary service time

  20. Assessment of friction between a rolling cylindrical element and a ...

    African Journals Online (AJOL)

    A cost-effective friction coefficient measuring technique was developed and tested. The technique involved the mounting of two sensing elements on the surface of rolls, in a manner that sought to measure simultaneously the normal and the tangential stresses during rolling. The instrumented roll termed “SGRoll” was ...

  1. QRL closes the circle

    CERN Multimedia

    2006-01-01

    Installation of the cryogenic distribution line (QRL) on sector 1-2, the last to be equipped. Installation began on the last sector of the cryogenic distribution line (QRL) about three weeks ahead of the revised schedule. Besides the recent start on sector 1-2, two other sectors are still being installed. QRL installation is expected to be complete by October. Installation of a single sector involves placing 325 elements and making almost 2000 internal welds. The average time now needed for installing each sector is about four and a half months, compared to the 11 months it took to install the first sector. 'Now people are very well trained and they know they can go fast with a good quality,' said QRL project engineer Germana Riddone. As proof of that quality, QRL technicians can look at the results of the latest pressure test on sector 5-6. There were no internal leaks in the sector and out of 1000 external interconnections there were only three leaks. The QRL project was hampered early on by technical prob...

  2. Locating a circle on a sphere

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schöbel, Anita

    2003-01-01

    We consider the problem of locating a spherical circle with respect to existing facilities on a sphere, such that the sum of weighted distances between the circle and the facilities is minimized, or such that the maximum weighted distance is minimized. The problem properties are analyzed, and we...... give solution procedures. When the circle to be located is restricted to be a great circle, some simplifications are possible....

  3. Locating a minisum circle in the plane

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schöbel, Anita

    2009-01-01

    We consider the problem of locating a circle with respect to existing facilities in the plane such that the sum of weighted distances between the circle and the facilities is minimized, i.e., we approximate a set of given points by a circle regarding the sum of weighted distances. If the radius...

  4. Quantum localisation on the circle

    Science.gov (United States)

    Fresneda, Rodrigo; Gazeau, Jean Pierre; Noguera, Diego

    2018-05-01

    Covariant integral quantisation using coherent states for semi-direct product groups is implemented for the motion of a particle on the circle. In this case, the phase space is the cylinder, which is viewed as a left coset of the Euclidean group E(2). Coherent states issued from fiducial vectors are labeled by points in the cylinder and depend also on extra parameters. We carry out the corresponding quantisations of the basic classical observables, particularly the angular momentum and the 2π-periodic discontinuous angle function. We compute their corresponding lower symbols. The quantum localisation on the circle is examined through the properties of the angle operator yielded by our procedure, its spectrum and lower symbol, its commutator with the quantum angular momentum, and the resulting Heisenberg inequality. Comparison with other approaches to the long-standing question of the quantum angle is discussed.

  5. Josephson junctions and circle maps

    Energy Technology Data Exchange (ETDEWEB)

    Bak, P; Bohr, T; Jensen, M H; Christiansen, P V

    1984-01-01

    The return map of a differential equation for the current driven Josephson junction, or the damped driven pendulum, is shown numerically to be a circle map. Phase locking, noise and hysteresis, can thus be understood in a simple and coherent way. The transition to chaos is related to the development of a cubic inflection point. Recent theoretical results on universal behavior at the transition to chaos can readily be checked experimentally by studying I-V characteristics. 17 references, 1 figure.

  6. The Revival of Research Circles: Meeting the Needs of Modern Aging and the Third Age

    Science.gov (United States)

    Ostlund, Britt

    2008-01-01

    This article provides evidence that it is worthwhile to reconsider the traditional research circle method as a means of involving people in the third age in fulfilling their needs to participate in learning activities and make their voices heard. The findings are based on three cases of research circles consistently driven by the interests of the…

  7. Defining Leadership: Collegiate Women's Learning Circles: A Qualitative Approach

    Science.gov (United States)

    Preston-Cunningham, Tammie; Elbert, Chanda D.; Dooley, Kim E.

    2017-01-01

    The researchers employed qualitative methods to evaluate first-year female students' definition of "leadership" through involvement in the Women's Learning Circle. The findings revealed that students defined leadership in two dimensions: traits and behaviors. The qualitative findings explore a multidimensional approach to the voices of…

  8. Circle activity of quality assurance in construction

    International Nuclear Information System (INIS)

    1982-05-01

    This book explains purpose, introduction 10 things to keep in mind, management and role of QC activity, TQC and QC circle activity in construction, introduction of the case of QC circle activity in a company like QC circle activity as TQC activity and QC circle for the bright future, case of experience of QC circle activity such as decreasing concrete loss, improvement of sleeve sticking on the ps wooden floor, overcoming handicap in field where one person works and point of QC 7 tools and order of improvement and management.

  9. Rolling Shutter Motion Deblurring

    KAUST Repository

    Su, Shuochen

    2015-06-07

    Although motion blur and rolling shutter deformations are closely coupled artifacts in images taken with CMOS image sensors, the two phenomena have so far mostly been treated separately, with deblurring algorithms being unable to handle rolling shutter wobble, and rolling shutter algorithms being incapable of dealing with motion blur. We propose an approach that delivers sharp and undis torted output given a single rolling shutter motion blurred image. The key to achieving this is a global modeling of the camera motion trajectory, which enables each scanline of the image to be deblurred with the corresponding motion segment. We show the results of the proposed framework through experiments on synthetic and real data.

  10. On a conjecture concerning helly circle graphs

    Directory of Open Access Journals (Sweden)

    Durán Guillermo

    2003-01-01

    Full Text Available We say that G is an e-circle graph if there is a bijection between its vertices and straight lines on the cartesian plane such that two vertices are adjacent in G if and only if the corresponding lines intersect inside the circle of radius one. This definition suggests a method for deciding whether a given graph G is an e-circle graph, by constructing a convenient system S of equations and inequations which represents the structure of G, in such a way that G is an e-circle graph if and only if S has a solution. In fact, e-circle graphs are exactly the circle graphs (intersection graphs of chords in a circle, and thus this method provides an analytic way for recognizing circle graphs. A graph G is a Helly circle graph if G is a circle graph and there exists a model of G by chords such that every three pairwise intersecting chords intersect at the same point. A conjecture by Durán (2000 states that G is a Helly circle graph if and only if G is a circle graph and contains no induced diamonds (a diamond is a graph formed by four vertices and five edges. Many unsuccessful efforts - mainly based on combinatorial and geometrical approaches - have been done in order to validate this conjecture. In this work, we utilize the ideas behind the definition of e-circle graphs and restate this conjecture in terms of an equivalence between two systems of equations and inequations, providing a new, analytic tool to deal with it.

  11. "Take Me to the Mathematical Circle!"

    OpenAIRE

    Veilande, Ingrida

    2012-01-01

    Preparing the students for various mathematical contests are the key goals of mathematical circles in Latvian schools. The reason why mathematical circles for students of primary schools are organised rather seldom is that problem sets of Olympiads are mainly created for students of 5th to 12th grades. The young participants of circles have to be introduced with the basic principles of Olimpiads mathematics too.

  12. Extrachromosomal circles of satellite repeats and 5S ribosomal DNA in human cells

    Directory of Open Access Journals (Sweden)

    Cohen Sarit

    2010-03-01

    Full Text Available Abstract Background Extrachomosomal circular DNA (eccDNA is ubiquitous in eukaryotic organisms and was detected in every organism tested, including in humans. A two-dimensional gel electrophoresis facilitates the detection of eccDNA in preparations of genomic DNA. Using this technique we have previously demonstrated that most of eccDNA consists of exact multiples of chromosomal tandemly repeated DNA, including both coding genes and satellite DNA. Results Here we report the occurrence of eccDNA in every tested human cell line. It has heterogeneous mass ranging from less than 2 kb to over 20 kb. We describe eccDNA homologous to human alpha satellite and the SstI mega satellite. Moreover, we show, for the first time, circular multimers of the human 5S ribosomal DNA (rDNA, similar to previous findings in Drosophila and plants. We further demonstrate structures that correspond to intermediates of rolling circle replication, which emerge from the circular multimers of 5S rDNA and SstI satellite. Conclusions These findings, and previous reports, support the general notion that every chromosomal tandem repeat is prone to generate eccDNA in eukryoric organisms including humans. They suggest the possible involvement of eccDNA in the length variability observed in arrays of tandem repeats. The implications of eccDNA on genome biology may include mechanisms of centromere evolution, concerted evolution and homogenization of tandem repeats and genomic plasticity.

  13. Ship Roll Damping Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2012-01-01

    limitations and large variations of the spectral characteristics of wave-induced roll motion. This tutorial paper presents an account of the development of various ship roll motion control systems together with the challenges associated with their design. It discusses the assessment of performance...

  14. Cosmology with rolling tachyon

    Indian Academy of Sciences (India)

    Email: sami@iucaa.ernet.in. Abstract. We examine the possibility of rolling tachyon to play the dual role of inflaton at early epochs and dark matter at late times. We argue that enough inflation can be generated with the rolling tachyon either by invoking the large number of branes or brane world assisted inflation. However ...

  15. Origins of Rolling Friction

    Science.gov (United States)

    Cross, Rod

    2017-01-01

    When a hard object rolls on a soft surface, or vice versa, rolling friction arises from deformation of the soft object or the soft surface. The friction force can be described in terms of an offset in the normal reaction force or in terms of energy loss arising from the deformation. The origin of the friction force itself is not entirely clear. It…

  16. Fairy circle landscapes under the sea

    KAUST Repository

    Ruiz-Reynés, Daniel

    2017-08-03

    Short-scale interactions yield large-scale vegetation patterns that, in turn, shape ecosystem function across landscapes. Fairy circles, which are circular patches bare of vegetation within otherwise continuous landscapes, are characteristic features of semiarid grasslands. We report the occurrence of submarine fairy circle seascapes in seagrass meadows and propose a simple model that reproduces the diversity of seascapes observed in these ecosystems as emerging from plant interactions within the meadow. These seascapes include two extreme cases, a continuous meadow and a bare landscape, along with intermediate states that range from the occurrence of persistent but isolated fairy circles, or solitons, to seascapes with multiple fairy circles, banded vegetation, and

  17. Locating a circle on a sphere

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schöbel, Anita

    2007-01-01

    We consider the problem of locating a spherical circle with respect to existing facilities on a sphere, such that the sum of distances between the circle and the facilities is minimized or such that the maximum distance is minimized. The problem properties are analyzed, and we give solution...... procedures. When the circle to be located is restricted to be a great circle, some simplifications are possible. The models may be used in preliminary studies on the location of large linear facilities on the earth's surface, such as superhighways, pipelines, and transmission lines, or in totally different...

  18. Information flow through the disaster circle

    DEFF Research Database (Denmark)

    Egedorf, Maren Marie; Villanueva Holm-Nielsen, Pablo

    The traditional view of the disaster circle is phase based. Disaster and development professionals recognize that the actions carried out in the various phases of the disaster management cycle are overlapping and build upon each other, having resilience as the overall goal. However information does...... not necessarily flow across the phases of the circle in an effective manner. This is particularly true for the information that crosses the disaster point of the circle. Organisations carry out assessments, surveys and baselines for various purposes, at various points of time in the disaster circle. Output...

  19. Fairy circle landscapes under the sea

    KAUST Repository

    Ruiz-Reyné s, Daniel; Gomila, Damià ; Sintes, Tomà s; Herná ndez-Garcí a, Emilio; Marbà , Nú ria; Duarte, Carlos M.

    2017-01-01

    Short-scale interactions yield large-scale vegetation patterns that, in turn, shape ecosystem function across landscapes. Fairy circles, which are circular patches bare of vegetation within otherwise continuous landscapes, are characteristic features of semiarid grasslands. We report the occurrence of submarine fairy circle seascapes in seagrass meadows and propose a simple model that reproduces the diversity of seascapes observed in these ecosystems as emerging from plant interactions within the meadow. These seascapes include two extreme cases, a continuous meadow and a bare landscape, along with intermediate states that range from the occurrence of persistent but isolated fairy circles, or solitons, to seascapes with multiple fairy circles, banded vegetation, and

  20. Cold rolling precision forming of shaft parts theory and technologies

    CERN Document Server

    Song, Jianli; Li, Yongtang

    2017-01-01

    This book presents in detail the theory, processes and equipment involved in cold rolling precision forming technologies, focusing on spline and thread shaft parts. The main topics discussed include the status quo of research on cold rolling precision forming technologies; the design and calculation of process parameters; the numerical simulation of cold rolling forming processes; and the equipment used in cold rolling forming. The mechanism of cold rolling forming is extremely complex, and research on the processes, theory and mechanical analysis of spline cold rolling forming has remained very limited to date. In practice, the forming processes and production methods used are mainly chosen on the basis of individual experience. As such, there is a marked lack of both systematic, theory-based guidelines, and of specialized books covering theoretical analysis, numerical simulation, experiments and equipment used in spline cold rolling forming processes – all key points that are included in this book and ill...

  1. Rolled-up nanotechnology: 3D photonic materials by design

    International Nuclear Information System (INIS)

    Böttner, Stefan; Jorgensen, Matthew R.; Schmidt, Oliver G.

    2016-01-01

    Rolled-up nanotechnology involves the deposition of strained material layers for subsequent release and relaxation into functional structures with applications spanning several disciplines. Originally developed for use with semiconductor materials, over the last decade the processes involved in rolled-up nanotechnology have been applied across a wide palette of materials resulting in applications (among others) in micro robotics, energy storage, electronics, and photonics. Here we highlight the key advancements and future directions in rolled-up photonics, focusing on the diverse demonstrations of rolled-up three-dimensional microresonators which enable integrated sensing, micro-lasing, and out-of-plane routing of light.

  2. A round robin study of flexible large-area roll-to-roll processed polymer solar cell modules

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Gevorgyan, Suren; Gholamkhass, Bobak

    2009-01-01

    A round robin for the performance of roll-to-roll coated flexible large-area polymer solar-cell modules involving 18 different laboratories in Northern America, Europe and Middle East is presented. The study involved the performance measurement of the devices at one location (Risø DTU) followed b...

  3. Activity know-how and doctrine of QC circle

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1976-09-15

    This books introduces activity know-how of QC circle giving descriptions of basic of QC circle activities, introduction operation and development and mind of QC circle activities, method for beginning of QC circle activity like, way order, motivation of introduction of QC circle activity, propel method of QC circle activities, such as leadership, brain storming, and rule of QC circle activity, management and propel method for improvement, development of QC circle activities. It also deals with doctrine of basic of QC circle, purpose, self improvement and group activity.

  4. Activity know-how and doctrine of QC circle

    International Nuclear Information System (INIS)

    1976-09-01

    This books introduces activity know-how of QC circle giving descriptions of basic of QC circle activities, introduction operation and development and mind of QC circle activities, method for beginning of QC circle activity like, way order, motivation of introduction of QC circle activity, propel method of QC circle activities, such as leadership, brain storming, and rule of QC circle activity, management and propel method for improvement, development of QC circle activities. It also deals with doctrine of basic of QC circle, purpose, self improvement and group activity.

  5. Direct and precise measurement of displacement and velocity of flexible web in roll-to-roll manufacturing systems

    International Nuclear Information System (INIS)

    Kang, Dongwoo; Lee, Eonseok; Choi, Young-Man; Lee, Taik-Min; Kim, Duk Young; Kim, Dongmin

    2013-01-01

    Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accurate as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm

  6. Direct and precise measurement of displacement and velocity of flexible web in roll-to-roll manufacturing systems

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dongwoo; Lee, Eonseok; Choi, Young-Man; Lee, Taik-Min [Advanced Manufacturing Systems Research Division, Korea Institute of Machinery and Materials, 156 Gajeongbuk-Ro, Yuseong-Gu, Daejeon 305-343 (Korea, Republic of); Kim, Duk Young [Nano-Opto-Mechatronics Lab., Dept. of Mechanical Eng., KAIST, 335 Gwahangno, Yuseong-Gu, Daejeon 305-701 (Korea, Republic of); Kim, Dongmin [Korea Research Institute of Standards and Science, 267 Gajeong-Ro, Yuseong-Gu, Daejeon 305-340 (Korea, Republic of)

    2013-12-15

    Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accurate as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm.

  7. Darboux cyclides and webs from circles

    KAUST Repository

    Pottmann, Helmut; Shi, Ling; Skopenkov, Mikhail

    2012-01-01

    to these surfaces based on the spherical model of 3D Möbius geometry, we provide computational tools for the identification of circle families on a given cyclide and for the direct design of those. In particular, we show that certain triples of circle families may

  8. The circle equation over finite fields

    DEFF Research Database (Denmark)

    Aabrandt, Andreas; Hansen, Vagn Lundsgaard

    2017-01-01

    Interesting patterns in the geometry of a plane algebraic curve C can be observed when the defining polynomial equation is solved over the family of finite fields. In this paper, we examine the case of C the classical unit circle defined by the circle equation x2 + y2 = 1. As a main result, we es...

  9. Beyond Quality Circles: Self-Managing Teams.

    Science.gov (United States)

    Sims, Henry P., Jr.; Dean, James W., Jr.

    1985-01-01

    This article reviews the quality circle concept, shows why its characteristics appeal to American executives, and examines some of its limitations. It looks at self-managing teams and discusses the reasons that adoptions have been relatively few. It then shows what organizational conditions are necessary for quality circles to evolve into teams.…

  10. Developing Soft Skills Using "Literature Circles"

    Science.gov (United States)

    Azmi, Mohd Nazri Bin Latiff

    2013-01-01

    This study investigates the impact of the implementation of "Literature Circles" in an Active Learning classroom in relations to developing soft skills among university students. The use of Literature Circles is a well-known strategy in teaching the students to be more creative, independent, and think out of the box. A group of…

  11. Roll force prediction of high strength steel using foil rolling theory in cold skin pass rolling

    International Nuclear Information System (INIS)

    Song, Gil Ho; Jung, Jae Chook

    2013-01-01

    Skin pass rolling is a very important process for applying a certain elongation to a strip in the cold rolling and annealing processes, which play an important role in preventing the stretching of the yield point when the material is processed. The exact prediction of the rolling force is essential for obtaining a given elongation with the steel grade and strip size. Unlike hot rolling and cold rolling, skin pass rolling is used to apply an elongation of within 2% to the strip. Under a small reduction, it is difficult to predict the rolling force because the elastic deformation behavior of the rolls is complicated and a model for predicting the rolling force has not yet been established. Nevertheless, the exact prediction of the rolling force in skin pass rolling has gained increasing importance in recent times with the rapid development of high strength steels for use in automobiles. In this study, the possibility of predicting the rolling force in skin pass rolling for producing various steel grades was examined using foil rolling theory, which is known to have similar elastic deformation behavior of rolls in the roll bite. It was found that a noncircular arc model is more accurate than a circular model in predicting the roll force of high strength steel below TS 980 MPa in skin pass rolling

  12. Towards roll-to-roll manufacturing of polymer photonic devices

    Science.gov (United States)

    Subbaraman, Harish; Lin, Xiaohui; Ling, Tao; Guo, L. Jay; Chen, Ray T.

    2014-03-01

    Traditionally, polymer photonic devices are fabricated using clean-room processes such as photolithography, e-beam lithography, reactive ion etching (RIE) and lift-off methods etc, which leads to long fabrication time, low throughput and high cost. We have utilized a novel process for fabricating polymer photonic devices using a combination of imprinting and ink jet printing methods, which provides high throughput on a variety of rigid and flexible substrates with low cost. We discuss the manufacturing challenges that need to be overcome in order to realize true implementation of roll-to-roll manufacturing of flexible polymer photonic systems. Several metrology and instrumentation challenges involved such as availability of particulate-free high quality substrate, development and implementation of high-speed in-line and off-line inspection and diagnostic tools with adaptive control for patterned and unpatterned material films, development of reliable hardware, etc need to be addressed and overcome in order to realize a successful manufacturing process. Due to extreme resolution requirements compared to print media, the burden of software and hardware tools on the throughput also needs to be carefully determined. Moreover, the effect of web wander and variations in web speed need to accurately be determined in the design of the system hardware and software. In this paper, we show the realization of solutions for few challenges, and utilizing these solutions for developing a high-rate R2R dual stage ink-jet printer that can provide alignment accuracy of web speed of 5m/min. The development of a roll-to-roll manufacturing system for polymer photonic systems opens limitless possibilities for the deployment of high performance components in a variety of applications including communication, sensing, medicine, agriculture, energy, lighting etc.

  13. Lengthening the lifetime of roll-to-roll produced polymer solar cells

    DEFF Research Database (Denmark)

    Madsen, Morten Vesterager

    the knowledge of the degradation mechanisms involved in roll-to-roll coated polymer solar cells. While only a part of the experiments have directly involved roll-to-roll coated devices, most of the work is applicable to coated devices. The first part of the dissertation is devoted to the study of in......The field of polymer solar cells is a field with an exponential growth in the number of published papers. It is a field defined by a set of challenges including; efficiency, stability and processability. Before all of these challenges have been addressed; polymer solar cells...... will not be a commercial success. This dissertation is devoted primarily to the study of the stability of polymer solar cells, and more specifically to designing and verifying experimental techniques, procedures, and automated solutions to stability tests and characterization. The goal of the project was to expand...

  14. Circles of quality in radiological safety

    International Nuclear Information System (INIS)

    Gonzalez F, J.A.

    1991-01-01

    The concept of Circles of quality arose in Japan like an option to capitalize the enormous potential that the workers had developed as a result of its training in the statistical tools of quality. There are presented a series of steps that could be given with the purpose of implementing a program of ALARA circles. The radiological safety is in it finishes instance responsibility of each hard-working one and there won't be a protection program that can work among apathetic people, it is in this sense where the ALARA circles can provide its maximum contribution creating a conscience of responsibility and participation

  15. NUMERICAL EVALUATION OF TEMPERATURE DISTRIBUTION IN THE ROLLING MILL ROLLS

    Directory of Open Access Journals (Sweden)

    José Claudino de Lira Júnior

    2013-06-01

    Full Text Available In hot rolling processes occur changes in the profile of the rolling mill rolls (expansion and contraction and constant wear due to mechanical stress and continuous thermal cycles of heating/cooling caused by contact rolled material- working roll and the cooling system by water jets in their surface, decreasing their lifetime. This paper presents a computational model to simulate the thermal performance of rolling mill rolls. The model was developed using the finite volume method for a transient two-dimensional system and allows calculating the temperature distribution of the rolling mill rolls under various conditions of service. Here it is investigated the influence of flow rate and temperature of the cooling water on the temperature distribution. The results show that the water temperature has greater influence than the water flow to control the surface temperature of the cylinders.

  16. Assessing the roll stability of heavy vehicles in South Africa

    CSIR Research Space (South Africa)

    Benade, R

    2016-07-01

    Full Text Available of these crashes involve heavy vehicle rollover. The regulations in the National Road Traffic Act of South Africa that govern heavy vehicle design do not directly address the roll stability of heavy vehicles. The internationally accepted method of regulating roll...

  17. Robust Circle Detection Using Harmony Search

    Directory of Open Access Journals (Sweden)

    Jaco Fourie

    2017-01-01

    Full Text Available Automatic circle detection is an important element of many image processing algorithms. Traditionally the Hough transform has been used to find circular objects in images but more modern approaches that make use of heuristic optimisation techniques have been developed. These are often used in large complex images where the presence of noise or limited computational resources make the Hough transform impractical. Previous research on the use of the Harmony Search (HS in circle detection showed that HS is an attractive alternative to many of the modern circle detectors based on heuristic optimisers like genetic algorithms and simulated annealing. We propose improvements to this work that enables our algorithm to robustly find multiple circles in larger data sets and still work on realistic images that are heavily corrupted by noisy edges.

  18. Area of Common Overlap of Three Circles

    National Research Council Canada - National Science Library

    Fewell, M. P

    2006-01-01

    .... The results presented here have general significance in the corpus of menstruation formulae, and could be of specific use in any quantitative application of the three-circle Venn diagram such as for...

  19. Darboux cyclides and webs from circles

    KAUST Repository

    Pottmann, Helmut

    2012-01-01

    Motivated by potential applications in architecture, we study Darboux cyclides. These algebraic surfaces of order ≤4 are a superset of Dupin cyclides and quadrics, and they carry up to six real families of circles. Revisiting the classical approach to these surfaces based on the spherical model of 3D Möbius geometry, we provide computational tools for the identification of circle families on a given cyclide and for the direct design of those. In particular, we show that certain triples of circle families may be arranged as so-called hexagonal webs, and we provide a complete classification of all possible hexagonal webs of circles on Darboux cyclides. © 2011 Elsevier B.V. All rights reserved.

  20. The magic circle and the puzzle piece

    OpenAIRE

    Juul, Jesper

    2008-01-01

    In a common description, to play a game is to step inside a concrete or metaphorical magic circle where special rules apply. In video game studies, this description has received an inordinate amount of criticism which the paper argues has two primary sources: 1. a misreading of the basic concept of the magic circle and 2. a somewhat rushed application of traditional theoretical concerns onto games. The paper argues that games studies must move beyond conventional criticisms of binary distinct...

  1. Person og Rolle

    DEFF Research Database (Denmark)

    Szatkowski, Janek

    2011-01-01

    Distinktionen mellem person og rolle forslås som grundlag for et præcist og anlytisk anvendeligt begreb om performativitet. Begrebet tager sigte på at beskrive enkeltindividers og gruppers kommunikation med henblik på hvordan kommunikation etableres. Performativitet gør det muligt at iagttage den...

  2. Ship Roll Motion Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2010-01-01

    . This tutorial paper presents an account of the development of various ship roll motion control systems and the challenges associated with their design. The paper discusses how to assess performance, the applicability of dierent models, and control methods that have been applied in the past....

  3. Rolling Cylinder Phase 1

    DEFF Research Database (Denmark)

    Margheritini, Lucia; Taraborrelli, Valeria Taraborrelli

    Margheritini and Valeria Taraborrelli(valeria.taraborrelli@hotmail.it) with a total of 3 day visit from the developers. Laboratory tests in irregular waves will be performed by Lucia Margheritini. The report is aimed at the first stage testing of the Rolling Cylinder wave energy device. This phase includes...

  4. Shock circle model for ejector performance evaluation

    International Nuclear Information System (INIS)

    Zhu, Yinhai; Cai, Wenjian; Wen, Changyun; Li, Yanzhong

    2007-01-01

    In this paper, a novel shock circle model for the prediction of ejector performance at the critical mode operation is proposed. By introducing the 'shock circle' at the entrance of the constant area chamber, a 2D exponential expression for velocity distribution is adopted to approximate the viscosity flow near the ejector inner wall. The advantage of the 'shock circle' analysis is that the calculation of ejector performance is independent of the flows in the constant area chamber and diffuser. Consequently, the calculation is even simpler than many 1D modeling methods and can predict the performance of critical mode operation ejectors much more accurately. The effectiveness of the method is validated by two experimental results reported earlier. The proposed modeling method using two coefficients is shown to produce entrainment ratio, efficiency and coefficient of performance (COP) accurately and much closer to experimental results than those of 1D analysis methods

  5. Students’ Scientific Circle of Obstetrics and Gynaecology

    Directory of Open Access Journals (Sweden)

    Ivan Polishchuk

    2017-06-01

    Full Text Available The students’ scientific circle is the kind of teaching obstetrics and gynaecology in a higher medical institution. The circle is an elective form of learning that allows the students to get deeper knowledge of a subject and to perfect themselves in the issues of diagnostics in obstetrics and gynaecology as well as to acquaint themselves with basic medical techniques. It helps identify students who are capable of scientific research and allows the students to improve their ability to analytical perception of professional information, the ability to present it to the audience, ask and answer the questions publicly. The article presents the results of practical and research activities of obstetric and gynaecologic section of the students’ scientific circle of Ivano-Frankivsk National Medical University.

  6. Orthogonal polynomials on the unit circle part 2 spectral theory

    CERN Document Server

    Simon, Barry

    2013-01-01

    This two-part book is a comprehensive overview of the theory of probability measures on the unit circle, viewed especially in terms of the orthogonal polynomials defined by those measures. A major theme involves the connections between the Verblunsky coefficients (the coefficients of the recurrence equation for the orthogonal polynomials) and the measures, an analog of the spectral theory of one-dimensional Schrödinger operators. Among the topics discussed along the way are the asymptotics of Toeplitz determinants (Szegő's theorems), limit theorems for the density of the zeros of orthogonal po

  7. Orthogonal polynomials on the unit circle part 1 classical theory

    CERN Document Server

    2009-01-01

    This two-part book is a comprehensive overview of the theory of probability measures on the unit circle, viewed especially in terms of the orthogonal polynomials defined by those measures. A major theme involves the connections between the Verblunsky coefficients (the coefficients of the recurrence equation for the orthogonal polynomials) and the measures, an analog of the spectral theory of one-dimensional Schrodinger operators. Among the topics discussed along the way are the asymptotics of Toeplitz determinants (Szegő's theorems), limit theorems for the density of the zeros of orthogonal po

  8. Rolling bearing analysis

    CERN Document Server

    Harris, Tedric A

    2001-01-01

    One of the most well-known experts in the field brings cutting-edge research to practitioners in the new edition of this important reference. Covers the improved mathematical calculations for rolling bearing endurance developed by the American Society of Mechanical Engineers and the Society of Lubrication and Tribology Engineers. Updated with new material on Condition-Based Maintenance, new testing methods, and new bearing materials.

  9. Roll of honour

    Energy Technology Data Exchange (ETDEWEB)

    Moxon, Suzanne

    1999-07-01

    This article gives details of the design and construction of dams selected by members of the dam construction industry for praise as feats of construction. The dams covered in the roll of honour include the dam at the Guri hydroelectric power station in Venezuela on the Caroni river, the Contra dam on the Verzrasca river in Switzerland, and the double curvature arc Ertan dam on the Yalong river in China. (UK)

  10. Shear Roll Mill Reactivation

    Science.gov (United States)

    2012-09-13

    pneumatically operated paste dumper and belt conveyor system, the loss in weight feeder system, the hydraulically operated shear roll mill, the pellet...out feed belt conveyor , and the pack out system comprised of the metal detector, scale, and pack out empty and full drum roller conveyors . Page | 4...feed hopper and conveyor supplying the loss in weight feeder were turned on, and it was verified that these items functioned as designed . The

  11. Ring rolling process simulation for geometry optimization

    Science.gov (United States)

    Franchi, Rodolfo; Del Prete, Antonio; Donatiello, Iolanda; Calabrese, Maurizio

    2017-10-01

    Ring Rolling is a complex hot forming process where different rolls are involved in the production of seamless rings. Since each roll must be independently controlled, different speed laws must be set; usually, in the industrial environment, a milling curve is introduced to monitor the shape of the workpiece during the deformation in order to ensure the correct ring production. In the present paper a ring rolling process has been studied and optimized in order to obtain anular components to be used in aerospace applications. In particular, the influence of process input parameters (feed rate of the mandrel and angular speed of main roll) on geometrical features of the final ring has been evaluated. For this purpose, a three-dimensional finite element model for HRR (Hot Ring Rolling) has been implemented in SFTC DEFORM V11. The FEM model has been used to formulate a proper optimization problem. The optimization procedure has been implemented in the commercial software DS ISight in order to find the combination of process parameters which allows to minimize the percentage error of each obtained dimension with respect to its nominal value. The software allows to find the relationship between input and output parameters applying Response Surface Methodology (RSM), by using the exact values of output parameters in the control points of the design space explored through FEM simulation. Once this relationship is known, the values of the output parameters can be calculated for each combination of the input parameters. After the calculation of the response surfaces for the selected output parameters, an optimization procedure based on Genetic Algorithms has been applied. At the end, the error between each obtained dimension and its nominal value has been minimized. The constraints imposed were the maximum values of standard deviations of the dimensions obtained for the final ring.

  12. Movement patterns of limb coordination in infant rolling.

    Science.gov (United States)

    Kobayashi, Yoshio; Watanabe, Hama; Taga, Gentaro

    2016-12-01

    Infants must perform dynamic whole-body movements to initiate rolling, a key motor skill. However, little is known regarding limb coordination and postural control in infant rolling. To address this lack of knowledge, we examined movement patterns and limb coordination during rolling in younger infants (aged 5-7 months) that had just begun to roll and in older infants (aged 8-10 months) with greater rolling experience. Due to anticipated difficulty in obtaining measurements over the second half of the rolling sequence, we limited our analysis to the first half. Ipsilateral and contralateral limbs were identified on the basis of rolling direction and were classified as either a stationary limb used for postural stability or a moving limb used for controlled movement. We classified the observed movement patterns by identifying the number of stationary limbs and the serial order of combinational limb movement patterns. Notably, older infants performed more movement patterns that involved a lower number of stationary limbs than younger infants. Despite the wide range of possible movement patterns, a small group of basic patterns dominated in both age groups. Our results suggest that the fundamental structure of limb coordination during rolling in the early acquisition stages remains unchanged until at least 8-10 months of age. However, compared to younger infants, older infants exhibited a greater ability to select an effective rotational movement by positioning themselves with fewer stationary limbs and performing faster limb movements.

  13. Quality circles: the nurse executive as mentor.

    Science.gov (United States)

    Flarey, D L

    1991-12-01

    Changes within and around the health care environment are forcing health care executives to reexamine their managerial and leadership styles to confront the resulting turbulence. The nurse executive is charged with the profound responsibility of directing the delivery of nursing care throughout the organization. Care delivered today must be of high quality. Declining financial resources as well as personnel shortages cause the executive to be an effective innovator in meeting the increasing demands. Quality circles offer the nurse executive an avenue of recourse. Circles have been effectively implemented in the health care setting, as has been consistently documented over time. By way of a participative management approach, quality circles may lead to increased employee morale and productivity, cost savings, and decreased employee turnover rates, as well as realization of socialization and self-actualization needs. A most effective approach to their introduction would be implementation at the first-line manager level. This promotes an acceptance of the concept at the management level as well as a training course for managers to implement the process at the unit level. The nurse executive facilitates the process at the first-line manager level. This facilitation will cause a positive outcome to diffuse throughout the entire organization. Quality circles offer the nurse executive the opportunity to challenge the existing environmental turmoil and effect a positive and lasting change.

  14. Everything within a Circle Is One Thing

    Centers for Disease Control (CDC) Podcasts

    2017-12-19

    Byron Breedlove, EID managing editor, discuses and reads his December 2017 cover essay, Everything within a Circle is One Thing.  Created: 12/19/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 12/19/2017.

  15. The Prague Linguistic Circle and Dialectics

    Czech Academy of Sciences Publication Activity Database

    Sládek, Ondřej

    -, č. 19 (2017), s. 352-357 E-ISSN 2037-2426 Institutional support: RVO:68378068 Keywords : The Prague Linguistic Circle * Jan Mukařovský * Structuralism * Structural Poetics * Dialectics Subject RIV: AJ - Letters, Mass-media, Audiovision OBOR OECD: Specific literatures

  16. Dynamics and bifurcations of random circle diffeomorphisms

    NARCIS (Netherlands)

    Zmarrou, H.; Homburg, A.J.

    2008-01-01

    We discuss iterates of random circle diffeomorphisms with identically distributed noise, where the noise is bounded and absolutely continuous. Using arguments of B. Deroin, V.A. Kleptsyn and A. Navas, we provide precise conditions under which random attracting fixed points or random attracting

  17. On circle map coupled map lattice

    CERN Document Server

    Ahmed, E

    2002-01-01

    Circle map in one and two dimensions is studied. Both its stability, synchronization using bounded control and persistence is discussed. This work is expected to be applicable in ecology where spatial effects are known to be important. Also it will be relevant to systems where delay effects are not negligible.

  18. Spray rolling aluminum alloy strip

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, Kevin M.; Delplanque, J.-P.; Johnson, S.B.; Lavernia, E.J.; Zhou, Y.; Lin, Y

    2004-10-10

    Spray rolling combines spray forming with twin-roll casting to process metal flat products. It consists of atomizing molten metal with a high velocity inert gas, cooling the resultant droplets in flight and directing the spray between mill rolls. In-flight convection heat transfer from atomized droplets teams with conductive cooling at the rolls to rapidly remove the alloy's latent heat. Hot deformation of the semi-solid material in the rolls results in fully consolidated, rapidly solidified product. While similar in some ways to twin-roll casting, spray rolling has the advantage of being able to process alloys with broad freezing ranges at high production rates. This paper describes the process and summarizes microstructure and tensile properties of spray-rolled 2124 and 7050 aluminum alloy strips. A Lagrangian/Eulerian poly-dispersed spray flight and deposition model is described that provides some insight into the development of the spray rolling process. This spray model follows droplets during flight toward the rolls, through impact and spreading, and includes oxide film formation and breakup when relevant.

  19. Rapid Identification of Emerging Human-Pathogenic Sporothrix Species with Rolling Circle Amplification

    NARCIS (Netherlands)

    Rodrigues, Anderson M; Najafzadeh, Mohammad J; de Hoog, G Sybren; de Camargo, Zoilo P

    2015-01-01

    Sporothrix infections are emerging as an important human and animal threat among otherwise healthy patients, especially in Brazil and China. Correct identification of sporotrichosis agents is beneficial for epidemiological surveillance, enabling implementation of adequate public-health policies and

  20. Rapid screening for human-pathogenic Mucorales using rolling circle amplification

    NARCIS (Netherlands)

    Dolatabadi, S; Najafzadeh, M J; de Hoog, G S

    2014-01-01

    Mucormycosis has emerged as a relatively common severe mycosis in patients with haematological and allogeneic stem cell transplantation. Source of transmission is from unidentified sources in the environment. Early diagnosis of infection and its source of contamination are paramount for rapid and

  1. The newest miracle drug: quality circles in hospitals.

    Science.gov (United States)

    McKinney, M M

    1984-01-01

    In recent years, a number of hospitals throughout the United States have been exploring the use of Japanese-style quality circles to reduce their operating expenses, improve productivity, and enhance the quality of work life for hospital employees. This article examines the organizational climate necessary for quality circles, methods used to implement quality circles, and management's role in guiding and responding to circle activities. Ideas for building and maintaining staff support are presented along with a cost/benefit analysis of quality circle programs. The author concludes that quality circles are most successful in hospitals where they are part of a larger organizational development effort. When administrators believe in their employees' ability to contribute to the institution and are willing to invest necessary time and resources in employee education and the measurement of quality circle achievements, quality circles can produce creative solutions to perplexing institutional problems.

  2. Locating a circle on the plane using the minimax criterion

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schoebel, Anita

    2006-01-01

    We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed.......We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed....

  3. The Acoustic Reality of the Kachruvian Circles: A Rhythmic Perspective

    Science.gov (United States)

    Low, Ee Ling

    2010-01-01

    This paper investigates whether the rhythmic properties of varieties of English found in each of the concentric circles of Kachru's model can, in any way, be elucidated by the "Three Circles" model. A measurement and comparison of the rhythm of three varieties of English: British English (from the Inner Circle), Singapore English (from…

  4. Circles of Support and Personalization: Exploring the Economic Case

    Science.gov (United States)

    Wistow, Gerald; Perkins, Margaret; Knapp, Martin; Bauer, Annette; Bonin, Eva-Maria

    2016-01-01

    Circles of Support aim to enable people with learning disabilities (and others) to live full lives as part of their communities. As part of a wider study of the economic case for community capacity building conducted from 2012 to 2014, we conducted a mixed methods study of five Circles in North West England. Members of these Circles were…

  5. The "Us" in Discuss: Grouping in Literature Circles

    Science.gov (United States)

    Batchelor, Katherine

    2012-01-01

    This article describes one middle school teacher's use of literature circles using heterogeneous grouping. It begins with a brief rationale for using literature circles in the language arts classroom. Next, it describes techniques to form literature circles. Then, it shares how to build and establish a supportive environment within each group. It…

  6. Forming Circle Formations of Anonymous Mobile Agents With Order Preservation

    NARCIS (Netherlands)

    Wang, Chen; Xie, Guangming; Cao, Ming

    2013-01-01

    We propose distributed control laws for a group of anonymous mobile agents to form desired circle formations when the agents move in the one-dimensional space of a circle. The agents are modeled by kinematic points. They share the common knowledge of the orientation of the circle, but are oblivious

  7. Roll back malaria update.

    Science.gov (United States)

    1999-10-01

    This article presents the activities under WHO's Roll Back Malaria (RBM) program in Asia, particularly in Nepal, Indonesia, India, Bangladesh, Sri Lanka and the Philippines. In India, the RBM program will start in 5 districts with a major malaria problem. A national committee has been formed by researchers, which will be able to provide operational and strategic support and research expertise in relation to malaria. In Bangladesh, the RBM program was initiated in the sparsely populated hill tract areas of Banderban and Chittagong where access to health care is very poor. At the district level, effective partnerships with private practitioners, politicians, community leaders, school teachers, the press and district Ministry of Health officials are operating to plan for rolling back malaria. In Myanmar, Cambodia, Lao People's Democratic Republic, Yunnan province of China, Vietnam, and Thailand, the focus of the RBM program was to move health care closer to the malaria-infected communities. WHO¿s Global Health Leadership Fellowship Programme, supported by the UN Foundation and Rockefeller Foundation, enables potential leaders to experience the work of UN agencies and contribute to the work of the organization for 2 years. Three out of four persons appointed to the RBM program received prestigious awards: Dr. Paola Marchesini of Brazil; Dr. Tieman Diarra of Mali; and Dr. Bob Taylor of the UK.

  8. Roll-to-roll UV imprint lithography for flexible electronics

    NARCIS (Netherlands)

    Maury, P.; Turkenburg, D.H.; Stroeks, N.; Giesen, P.; Barbu, I.; Meinders, E.R.; Bremen, A. van; Iosad, N.; Werf, R. van der; Onvlee, H.

    2011-01-01

    We propose a roll-to-roll UV imprint lithography tool as a way to pattern flexible PET foil with µm-resolution. As a way to overcome dimensional instability of the foil and its effect on overlay, a self-align approach was investigated, that permits to make several layers in a single lithography

  9. RELATIONSHIP BETWEEN ROLLING AND SLIP RESISTANCE IN ROLLING BEARINGS

    Directory of Open Access Journals (Sweden)

    L. M. Bondarenko

    2016-06-01

    Full Text Available Purpose. About one of the causes of slip rolling is known from the second half of the 19th century, it was believed that the slip resistance appears at the place of contact due to different speeds on the arc of contact. Only in the mid-20th century it was proved that this resistance is negligible in rolling resistance. However (for some unknown reason it is ignored the fact that in practice in rolling bearings may rotate both the inner ring with a stationary outer one, and vice versa almost in equal relations. It is not taken into account the fact that the ball or roller in the rolling bearings runs the different distance along the roller path of the outer and inner bearing cages in one revolution. This fact is not taken into account in determining the calculated values for the friction coefficient of a rolling bearing reduced to the shaft. Therefore, the aim of this work is to determine the influence of path length on the track riding the outer and inner race of the bearing on the determination of the calculated value of the coefficient of friction of rolling bearings is given to the shaft. Methodology. The solution technique is based on the theory of plane motion of a rigid body, the theory of Hertzian contact deformation and the analytical dependencies for determination of coefficient of rolling friction. Findings. The obtained dependences on determination of rolling resistance of the balls or rollers along the bearing tracks of inner and outer bearing cages as well as path difference metering of the rolling on them allows to analytically obtain the rolling resistance and slipping for any size of bearings and different devices of bearing units. It is also possible at the design stage of rolling nodes to handle not only the design but also the content of the node. Originality. Using the analytical dependences for determination of the rolling resistance of bodies at point and line contacts, and also account for the difference in the path of the

  10. CHARACTERISTICS OF HYDROCARBON EXPLOITATION IN ARCTIC CIRCLE

    Directory of Open Access Journals (Sweden)

    Vanja Lež

    2013-12-01

    Full Text Available The existence of large quantities of hydrocarbons is supposed within the Arctic Circle. Assumed quantities are 25% of the total undiscovered hydrocarbon reserves on Earth, mostly natural gas. Over 500 major and minor gas accumulations within the Arctic Circle were discovered so far, but apart from Snøhvit gas field, there is no commercial exploitation of natural gas from these fields. Arctic gas projects are complicated, technically hard to accomplish, and pose a great threat to the return of investment, safety of people and equipment and for the ecosystem. Russia is a country that is closest to the realization of the Arctic gas projects that are based on the giant gas fields. The most extreme weather conditions in the seas around Greenland are the reason why this Arctic region is the least explored and furthest from the realization of any gas project (the paper is published in Croatian .

  11. A vicious circle in chronic lymphoedema pathophysiology?

    DEFF Research Database (Denmark)

    Cucchi, F; Rossmeislova, L; Simonsen, L

    2017-01-01

    Chronic lymphoedema is a disease caused by a congenital or acquired damage to the lymphatic system and characterized by complex chains of pathophysiologic events such as lymphatic fluid stasis, chronic inflammation, lymphatic vessels impairment, adipose tissue deposition and fibrosis. These event....... Together, these observations indicate strong reciprocal relationship between lymphatics and adipose tissue and suggest a possible key role of the adipocyte in the pathophysiology of chronic lymphoedema's vicious circle....

  12. Stone circles: form and soil kinematics.

    Science.gov (United States)

    Hallet, Bernard

    2013-01-01

    Distinct surface patterns are ubiquitous and diverse in soils of polar and alpine regions, where the ground temperature oscillates about 0°C. They constitute some of the most striking examples of clearly visible, abiotic self-organization in nature. This paper outlines the interplay of frost-related physical processes that produce these patterns spontaneously and presents unique data documenting subsurface soil rotational motion and surface displacement spanning 20 years in well-developed circles of soil outlined by gravel ridges. These sorted circles are particularly attractive research targets for a number of reasons that provide focus for this paper: (i) their exceptional geometric regularity captures the attention of any observer; (ii) they are currently forming and evolving, hence the underlying processes can be monitored readily, especially because they are localized near the ground surface on a scale of metres, which facilitates comprehensive characterization; and (iii) a recent, highly successful numerical model of sorted circle development helps to draw attention to particular field observations that can be used to assess the model, its assumptions and parameter choices, and to the considerable potential for synergetic field and modelling studies.

  13. LEDs are on a roll

    NARCIS (Netherlands)

    Blom, P.W.M.; Mol, A.M.B. van

    2011-01-01

    Light-emitting diodes are more efficient than conventional lighting, but high production costs limit their uptake. Organic versions that can be produced using a cheap newspaper-style 'roll-to-roll' printing process are likely to revolutionize our lighting and signage, say Paul Blom and Ton van Mol.

  14. Anisotropic constant-roll inflation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Asuka; Soda, Jiro [Kobe University, Department of Physics, Kobe (Japan)

    2018-01-15

    We study constant-roll inflation in the presence of a gauge field coupled to an inflaton. By imposing the constant anisotropy condition, we find new exact anisotropic constant-roll inflationary solutions which include anisotropic power-law inflation as a special case. We also numerically show that the new anisotropic solutions are attractors in the phase space. (orig.)

  15. Rolling up a Graphene Sheet

    NARCIS (Netherlands)

    Calvaresi, Matteo; Quintana, Mildred; Rudolf, Petra; Zerbetto, Francesco; Prato, Maurizio

    2013-01-01

    Carbon Nanotubes, CNTs, have been described as rolled-up graphene layers. Matching this concept to experiments has been a great experimental challenge for it requires a method to exfoliate graphite, generate ordered and stable dangling carbon bonds, and roll up the layer without affecting the

  16. Rudder roll stabilization for ships

    NARCIS (Netherlands)

    van Amerongen, J.; van der Klugt, P.G.M.; van Nauta lemke, H.R.

    1990-01-01

    This paper describes the design of an autopilot for rudder roll stabilization for ships. This autopilot uses the rudder not only for course keeping but also for reduction of the roll. The system has a series of properties which make the controller design far from straightforward: the process has

  17. Computational design of rolling bearings

    CERN Document Server

    Nguyen-Schäfer, Hung

    2016-01-01

    This book comprehensively presents the computational design of rolling bearings dealing with many interdisciplinary difficult working fields. They encompass elastohydrodynamics (EHD), Hertzian contact theory, oil-film thickness in elastohydrodynamic lubrication (EHL), bearing dynamics, tribology of surface textures, fatigue failure mechanisms, fatigue lifetimes of rolling bearings and lubricating greases, Weibull distribution, rotor balancing, and airborne noises (NVH) in the rolling bearings. Furthermore, the readers are provided with hands-on essential formulas based on the up-to-date DIN ISO norms and helpful examples for computational design of rolling bearings. The topics are intended for undergraduate and graduate students in mechanical and material engineering, research scientists, and practicing engineers who want to understand the interactions between these working fields and to know how to design the rolling bearings for automotive industry and many other industries.

  18. Inkjet printing as a roll-to-roll compatible technology for the production of large area electronic devices on a pre-industrial scale

    NARCIS (Netherlands)

    Teunissen, P.; Rubingh, E.; Lammeren, T. van; Abbel, R.J.; Groen, P.

    2014-01-01

    Inkjet printing is a promising approach towards the solution processing of electronic devices on an industrial scale. Of particular interest is the production of high-end applications such as large area OLEDs on flexible substrates. Roll-to-roll (R2R) processing technologies involving inkjet

  19. Introducing Nine-Point Circle to Junior High School Students

    Science.gov (United States)

    Fiangga, S.; Azizah, M. A. N.; Rini, R. N. K.; Hidayanti, A. N.

    2018-01-01

    The concept of circles is an ancient concept that has appeared since Ancient Egypt from which this concept gives many significant contributions in mathematics’ development until now. Nevertheless, the concept of circles hides many uncover mysterious features that are of applications in mathematics. One of the mysterious features is the Nine-Point Circle. This Nine-point circle is also known as Euler’s circle, six-point circle, Feuerbach’s circle, the twelve-point circle, and many others. Because of these different names, there have been misunderstand among mathematicians about the Nine-Point Circle’s history. Besides, the discussion of Nine-Point Circle can be used to be an initial material to explain elementary geometry topic in junior high school’s level curriculum of 2013. Therefore, this concept needs to be delivered to the students as a geometry introduction. A possible form of the integration historical aspect of Nine-point circle is suggested in this paper as well as its importance in the curriculum of 2013.

  20. Stress and accidental defect detection on rolling mill rolls

    International Nuclear Information System (INIS)

    Auzas, J.-D.

    1999-01-01

    During the rolling mill process, rolls are submitted to high pressures that can lead to local decohesion or metallurgical changes. Both these cracks or softened areas must be detected as soon as they appear because of the risk of spalling, marks on the product, and mill wreck. These defects can be detected using the eddy current method, and particularly sensors specially developed for micro-defects detection. These sensors must be adapted to the environment of a roll grinding machine on which they must be installed. Users' schedule of conditions also require them to be attached to a wide range of eddy current generator and automatic computerized interpretation. Mill requirements for new high tech roll grades and quality lead to continuous development and improvement of the tools that will provide immediate 'go - no go' information. This paper is an update of these developments. (author)

  1. Roll bonding of strained aluminium

    DEFF Research Database (Denmark)

    Staun, Jakob M.

    2003-01-01

    This report investigates roll bonding of pre-strained (å ~ 4) aluminium sheets to produce high strain material from high purity aluminium (99.996%) and commercial pure aluminium (99.6%). The degree of bonding is investigated by optical microscopy and ultrasonic scanning. Under the right...... of the cross rolled volume fraction is found. To further asses this effect, and the anisotropy, it is necessary to acquire knowledge about both texture and microstructure, e.g. by TEM. Roll bonding of pre-strained aluminium is found to be a possible alternative to ARB in the quest for ultra-fine grained...

  2. Circle Maps and C*-algebras

    DEFF Research Database (Denmark)

    Schmidt, Thomas Lundsgaard; Thomsen, Klaus

    2015-01-01

    We consider a construction of $C^*$-algebras from continuous piecewise monotone maps on the circle which generalizes the crossed product construction for homeomorphisms and more generally the construction of Renault, Deaconu and Anantharaman-Delaroche for local homeomorphisms. Assuming that the map...... is surjective and not locally injective we give necessary and sufficient conditions for the simplicity of the $C^*$-algebra and show that it is then a Kirchberg algebra. We provide tools for the calculation of the K-theory groups and turn them into an algorithmic method for Markov maps....

  3. Rolling Process Modeling Report: Finite-Element Prediction of Roll Separating Force and Rolling Defects

    Energy Technology Data Exchange (ETDEWEB)

    Soulami, Ayoub [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Paxton, Dean M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Burkes, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-04-23

    Pacific Northwest National Laboratory (PNNL) has been investigating manufacturing processes for the uranium-10% molybdenum (U-10Mo) alloy plate-type fuel for the U.S. high-performance research reactors. This work supports the Convert Program of the U.S. Department of Energy’s National Nuclear Security Administration (DOE/NNSA) Global Threat Reduction Initiative. This report documents modeling results of PNNL’s efforts to perform finite-element simulations to predict roll separating forces and rolling defects. Simulations were performed using a finite-element model developed using the commercial code LS-Dyna. Simulations of the hot rolling of U-10Mo coupons encapsulated in low-carbon steel have been conducted following two different schedules. Model predictions of the roll-separation force and roll-pack thicknesses at different stages of the rolling process were compared with experimental measurements. This report discusses various attributes of the rolled coupons revealed by the model (e.g., dog-boning and thickness non-uniformity).

  4. Systematics of constant roll inflation

    Science.gov (United States)

    Anguelova, Lilia; Suranyi, Peter; Wijewardhana, L. C. R.

    2018-02-01

    We study constant roll inflation systematically. This is a regime, in which the slow roll approximation can be violated. It has long been thought that this approximation is necessary for agreement with observations. However, recently it was understood that there can be inflationary models with a constant, and not necessarily small, rate of roll that are both stable and compatible with the observational constraint ns ≈ 1. We investigate systematically the condition for such a constant-roll regime. In the process, we find a whole new class of inflationary models, in addition to the known solutions. We show that the new models are stable under scalar perturbations. Finally, we find a part of their parameter space, in which they produce a nearly scale-invariant scalar power spectrum, as needed for observational viability.

  5. In the vicious circle of fear

    International Nuclear Information System (INIS)

    Zischka, A.

    1980-01-01

    Fear is the great driving force, the basic effect, without which there would be no adaption to new living conditions, and no provision for the future. But fear has a positive influence only as long as it does not gain the upper hand, for then it makes human beings blind and stifles activity. What is important, and will remain so, is the equilibrium between fear and courage, caution and the desire for action, optimism und pessimism. This equilibrium has now been disturbed in the western countries - and only here. Our present fears give rise to hardly any positive measures, but prevent provision for the future. We are threatened with failure due to the manipulated conversion of fear from the maintenance of life to an effect which destroys life. In this way we got into a vicious circle of fear: we must try to weaken the imagined dangers by emphasising the true conditions. The author discusses how the viscious circle can be broken. (orig.) 891 UA/orig. 892 MKO [de

  6. Grease lubrication in rolling bearings

    CERN Document Server

    Lugt, Piet M

    2012-01-01

    The definitive book on the science of grease lubrication for roller and needle bearings in industrial and vehicle engineering. Grease Lubrication in Rolling Bearings provides an overview of the existing knowledge on the various aspects of grease lubrication (including lubrication systems) and the state of the art models that exist today. The book reviews the physical and chemical aspects of grease lubrication, primarily directed towards lubrication of rolling bearings. The first part of the book covers grease composition, properties and rheology, including thermal

  7. Rolling Resistance Measurement and Model Development

    DEFF Research Database (Denmark)

    Andersen, Lasse Grinderslev; Larsen, Jesper; Fraser, Elsje Sophia

    2015-01-01

    There is an increased focus worldwide on understanding and modeling rolling resistance because reducing the rolling resistance by just a few percent will lead to substantial energy savings. This paper reviews the state of the art of rolling resistance research, focusing on measuring techniques, s......, surface and texture modeling, contact models, tire models, and macro-modeling of rolling resistance...

  8. Empirical Evaluation of Different Feature Representations for Social Circles Detection

    Science.gov (United States)

    2015-06-16

    study and compare the performance on the available labelled Facebook data from the Kaggle competition on learning social circles in networks . We...Kaggle competition on learning social circles in networks [5]. The data consist of hand- labelled friendship egonets from Facebook and a set of 57...16. SECURITY CLASSIFICATION OF: Social circles detection is a special case of community detection in social network that is currently attracting a

  9. Locating a circle on the plane using the minimax criterion

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schöbel, Anita

    2009-01-01

    We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circumference of the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed......We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circumference of the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed...

  10. Locating a general minisum 'circle' on a plane

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Körner, Mark-Christoph

    2011-01-01

    We approximate a set of given points in the plane by the boundary of a convex and symmetric set which is the unit circle of some norm. This generalizes previous work on the subject which considers Euclidean circles only. More precisely, we examine the problem of locating and scaling the unit circle...... of some given norm k with respect to given points on the plane such that the sum of weighted distances (as measured by the same norm k) between the circumference of the circle and the points is minimized. We present general results and are able to identify a finite dominating set in the case that k...

  11. CircleBoard-Pro: Concrete manipulative-based learning cycle unit for learning geometry

    Science.gov (United States)

    Jamhari, Wongkia, Wararat

    2018-01-01

    Currently, a manipulative is commonly used in mathematics education as a supported tool for teaching and learning. With engaging natural interaction of a concrete manipulative and advantages of a learning cycle approach, we proposed the concrete manipulative-based learning cycle unit to promote mathematics learning. Our main objectives are to observe possibilities on the use of a concrete manipulative in learning geometry, and to assess students' understanding of a specific topic, angle properties in a circle, of secondary level students. To meet the first objective, the concrete manipulative, called CricleBoard-Pro, was designed. CircleBoard-Pro is built for easy to writing on or deleting from, accurate angle measurement, and flexible movement. Besides, learning activities and worksheets were created for helping students to learn angle properties in a circle. Twenty eighth graders on a lower secondary school in Indonesia were voluntarily involved to learn mathematics using CircleBoard-Pro with the designed learning activities and worksheets. We informally observed students' performance by focusing on criteria of using manipulative tools in learning mathematics while the learning activities were also observed in terms of whether they work and which step of activities need to be improved. The results of this part showed that CircleBoard-Pro complied the criteria of the use of the manipulative in learning mathematics. Nevertheless, parts of learning activities and worksheets need to be improved. Based on the results of the observation, CircleBoard-Pro, learning activities, and worksheets were merged together and became the CircleBoardPro embedded on 5E (Engage - Explore - Explain - Elaborate - Evaluate) learning cycle unit. Then, students understanding were assessed to reach the second objective. Six ninth graders from an Indonesian school in Thailand were recruited to participate in this study. Conceptual tests for both pre-and post-test, and semi

  12. The National Shipbuilding Research Program. Proceedings of the IREAPS Technical Symposium. Paper No. 20: The Utility of Quality Circles and Productivity Teams in U.S. Shipbuilding

    National Research Council Canada - National Science Library

    Harper, Stephen E

    1982-01-01

    .... The average return on investment for quality circles is 6 to 1. QC's are a simple, but effective, technique for problem solving which involves employees and increases motivation, communication, and productivity...

  13. Enhancing roll stability of heavy vehicle by LQR active anti-roll bar control using electronic servo-valve hydraulic actuators

    Science.gov (United States)

    Vu, Van Tan; Sename, Olivier; Dugard, Luc; Gaspar, Peter

    2017-09-01

    Rollover of heavy vehicle is an important road safety problem world-wide. Although rollovers are relatively rare events, they are usually deadly accidents when they occur. The roll stability loss is the main cause of rollover accidents in which heavy vehicles are involved. In order to improve the roll stability, most of modern heavy vehicles are equipped with passive anti-roll bars to reduce roll motion during cornering or riding on uneven roads. However these may be not sufficient to overcome critical situations. This paper introduces the active anti-roll bars made of four electronic servo-valve hydraulic actuators, which are modelled and integrated in a yaw-roll model of a single unit heavy vehicle. The control signal is the current entering the electronic servo-valve and the output is the force generated by the hydraulic actuator. The active control design is achieved solving a linear optimal control problem based on the linear quadratic regulator (LQR) approach. A comparison of several LQR controllers is provided to allow for tackling the considered multi-objective problems. Simulation results in frequency and time domains show that the use of two active anti-roll bars (front and rear axles) drastically improves the roll stability of the single unit heavy vehicle compared with the passive anti-roll bar.

  14. Quality Circles: Determination of Significant Factors for Success an a General Model for Implementing a Quality Circle Process.

    Science.gov (United States)

    1981-06-01

    receive for contributions to quality and productivity /4:Apdx-47. The initiative for the Quality Circle concept came from Dr Kaoru Ishikawa , a...eloquently summarized by the "Father of Quality Circles", Dr Kaoru Ishikawa . He sees that, although Japan started with the worst quality reputation among...Perceptions of Influence, Academy of Management Journal. December 1974, pp 649-bz. 49. Ishikawa , Kaoru . S.C. Circle Activities. Union of Japanese Scientists and

  15. Meromorphic Vector Fields and Circle Packings

    DEFF Research Database (Denmark)

    Dias, Kealey

    The objective of the Ph.D. project is to initiate a classification of bifurcations of meromorphic vector fields and to clarify their relation to circle packings. Technological applications are to image analysis and to effective grid generation using discrete conformal mappings. The two branches...... of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions or meromorphic (allowing poles...... as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic vector fields. Restricting...

  16. Squaring the circle of healthcare supplies.

    Science.gov (United States)

    Böhme, Tillmann; Williams, Sharon; Childerhouse, Paul; Deakins, Eric; Towill, Denis

    2014-01-01

    The purpose of this paper is to use a systems lens to assess the comparative performance of healthcare supply chains and provide guidance for their improvement. A well-established and rigorous multi-method audit methodology, based on the uncertainty circle model, yields an objective assessment of value stream performance in eight Australasian public sector hospitals. Cause-effect analysis identifies the major barriers to achieving smooth, seamless flows. Potentially high-leverage remedial actions identified using systems thinking are examined with the aid of an exemplar case. The majority of the healthcare value streams studied are underperforming compared with those in the European automotive industry. Every public hospital appears to be caught in the grip of vicious circles of system uncertainty, in large part being caused by problems of their own making. The single exception is making good progress towards seamless functional integration, which has been achieved by elevating supply chain management to a core competence; having a clearly articulated supply chain vision; adopting a systems approach; and, managing supplies with accurate information. The small number of cases limits the generalisability of the findings at this time. Hospital supply chain managers endeavouring to achieve smooth and seamless supply flows should attempt to elevate the status of supplies management within their organisation to that of a core competence, and should use accurate information to manage their value streams holistically as a set of interwoven processes. A four-level prism model is proposed as a useful framework for thus improving healthcare supply delivery systems. Material flow concepts originally developed to provide objective assessments of value stream performance in commercial settings are adapted for use in a healthcare setting. The ability to identify exemplar organisations via a context-free uncertainty measure, and to use systems thinking to identify high

  17. The effect of roll gap geometry on microstructure in cold-rolled aluminum

    DEFF Research Database (Denmark)

    Mishin, Oleg; Bay, B.; Winther, G.

    2004-01-01

    Microstructure and texture are analyzed through the thickness of two aluminum plates cold-rolled 40% with different roll gap geometries. It is found that both texture and microstructure are strongly affected by the rolling geometry. After rolling with intermediate-size draughts a rolling-type tex......Microstructure and texture are analyzed through the thickness of two aluminum plates cold-rolled 40% with different roll gap geometries. It is found that both texture and microstructure are strongly affected by the rolling geometry. After rolling with intermediate-size draughts a rolling...... layers. In these layers, extended planar dislocation boundaries are frequently found to be inclined closely to the rolling direction. The subsurface and central layers of this plate exhibit microstructures similar to those in the plate rolled with intermediate draughts. It is suggested...

  18. Quality Circles in Higher Education: Quality, Satisfaction, and Climate.

    Science.gov (United States)

    Kay, Carol; Healy, Margaret

    The effect of quality circles at Iowa State University on absenteeism, performance evaluation, perceptions of the organization climate, job satisfaction, and perceived opportunities for professional and personal growth was measured in this study. The process of quality circles is designed to promote job fulfillment and organizational productivity…

  19. D'Nealian Handwriting versus Circle-Stick Print.

    Science.gov (United States)

    Thurber, Donald N.

    This paper argues against teaching children to make letters using circle-stick writing. It contends that the circle-stick method requires continued pen/pencil lifts hindering rhythm or flow in the writing process and that there is little carry-over value into cursive writing as the two scripts are totally different. D'Nealian print, one type of…

  20. An Effective Time and Management Strategy in Quality Circles.

    Science.gov (United States)

    Halverson, Don E.

    Contending that participation in quality circles enhances effective time management by school administrators and teachers, this guide provides both a theoretical briefing and practical recommendations for better time management. A pre- posttest prefaces a review of basic concepts of quality circles with reference to the work of Abraham Maslow,…

  1. Building quality into academic programmes using quality circles | Ivy ...

    African Journals Online (AJOL)

    The use of teams or quality circles is a relatively new approach to quality improvement in higher education in South Africa. This article describes some of the advantages in using the approach and some of the pitfalls that need to be considered. The debate of the "quality circle life cycle", which culminates in the demise of the ...

  2. Growing a Circle of Courage Culture: One School's Journey

    Science.gov (United States)

    Espiner, Deborah; Guild, Diane

    2010-01-01

    Mt. Richmond Special School is the first Circle of Courage school in New Zealand. The school reflects the richness of the cultural and learning diversity found in many New Zealand schools. Located in the heart of South Auckland, the school's 130 students represent a wide range of ethnic backgrounds. The universal values in the Circle of Courage…

  3. Finding the Maximal Area of Bounded Polygons in a Circle

    Science.gov (United States)

    Rokach, Arie

    2005-01-01

    The article deals with the area of polygons that are inscribed in a given circle. Naturally, the following question arises: Among all n-polygons that are inscribed in a given circle, which one has the biggest area? Intuitively, it may be guessed that is suitable for secondary students, and without any use id calculus, but only using very…

  4. Robust Rudder Roll Damping Control

    DEFF Research Database (Denmark)

    Yang, C.

    The results of a systematic research to solve a specific ship motion control problem, simultaneous roll damping and course keeping using the rudder are presented in this thesis. The fundamental knowledge a priori is that rudder roll damping is highly sensitive to the model uncertainty, therefore H-infinity...... theory is used to deal with the problem. The necessary mathematical tools and the H-Infinity theory as the basis of controller design are presented in Chapter 2 and 3. The mu synthesis and the D-K iteration are introduced in Chapter 3. The ship dynamics and modeling technology are discussed in Chapter 4...

  5. Isotropic compression of cohesive-frictional particles with rolling resistance

    NARCIS (Netherlands)

    Luding, Stefan; Benz, Thomas; Nordal, Steinar

    2010-01-01

    Cohesive-frictional and rough powders are the subject of this study. The behavior under isotropic compression is examined for different material properties involving Coulomb friction, rolling-resistance and contact-adhesion. Under isotropic compression, the density continuously increases according

  6. Rolling motion in moving droplets

    Indian Academy of Sciences (India)

    motions. The two limits of a thin sheet-like drop in sliding motion on a surface, and a spherical drop in roll, have been extensively .... rigid body rotation. The solid body rotation makes sense in the context of small Reynolds. (Re) number flows ...

  7. The Prague Linguistic Circle and Dialectics

    Directory of Open Access Journals (Sweden)

    Ondřej Sládek

    2017-12-01

    Full Text Available The study deals with dialectics in the context of the Prague Linguistic Circle, particularly in the context of Jan Mukařovský’s thinking. The essay presents 1 main sources of Mukařovský’s dialectics, and outlines 2 Mukařovský’s dialectical method. The notion of dialectics appears in Mukařovský’s scholarly work in a set of connections. He applied dialectics as a method, manner or form of rationality. It served as a means of gaining knowledge about the world, specific phenomena and objects, their essence, interconnectedness as well as development. Mukařovský also used it as a procedure for resolving contradictions (antinomies that he encountered in his scientific explorations and in ordinary practical activities. He understood dialectical thinking as dynamic, open, and pluralist thinking striving to reflect reality as a constant process. Gradual coming together of dialectics and materialism, evident in Mukařovský’s scholarly works from the mid-1930s, resulted, ten years later, in a public adoption of dialectical materialism.

  8. Quality circles--new wave or fad?

    Science.gov (United States)

    Herkimer, A G

    1984-07-01

    The American healthcare industry must avoid the dangers of commitment to bureaucratic organizational thinking and be willing to experiment with Theory Z and quality circles. Productivity depends on trust, subtlety and intimacy. The industry must acknowledge that management style and organizational form are nothing more than facets of the larger organization of society. The ultimate goal should be to understand how the structure of society and the management of healthcare organizations can be coordinated. The common thread in Japanese life is intimacy. The caring, support, and disciplined unselfishness which makes life possible come through close social relationships. Accordingly, there is (or at least, there should be) a common thread in this nation's healthcare industry--the desire to render quality health care in an effective and efficient manner. The underlying messages are many, but they are not overwhelming. Perhaps the first message to healthcare managers is that a healthcare delivery system can realize the full potential of its employees only if it invests in their training and then shares with them the power to influence decisions. Without training, the invitation to participate in decision making will lead only to frustration and conflict. Without a sharing of decision-making power, an investment in training will be both frustrating and wasteful.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Geršgorin and his circles

    CERN Document Server

    Varga, Richard S

    2004-01-01

    TheGer? sgorin CircleTheorem, averywell-known resultin linear algebra today, stems from the paper of S. Ger? sgorin in 1931 (which is reproduced in AppendixD)where,givenanarbitraryn×ncomplexmatrix,easyarithmetic operationsontheentriesofthematrixproducendisks,inthecomplexplane, whose union contains all eigenvalues of the given matrix. The beauty and simplicity of Ger? sgorin’s Theorem has undoubtedly inspired further research in this area, resulting in hundreds of papers in which the name “Ger? sgorin” appears. The goal of this book is to give a careful and up-to-date treatment of various aspects of this topic. The author ?rst learned of Ger? sgorin’s results from friendly conversations with Olga Taussky-Todd and John Todd, which inspired me to work in this area.Olgawasclearlypassionateaboutlinearalgebraandmatrixtheory,and her path-?nding results in these areas were like a magnet to many, including this author! It is the author’s hope that the results, presented here on topics related to Ger? sgorin...

  10. Androgen circle of polycystic ovary syndrome.

    Science.gov (United States)

    Homburg, Roy

    2009-07-01

    Although the aetiology of polycystic ovary syndrome (PCOS) is still not known and the search for causative genes is proving elusive, it is generally agreed that hyperandrogenism is at the heart of the syndrome. Here, it is proposed that excess androgens are the root cause of PCOS starting from their influence on the female fetus in programming gene expression, producing the characteristic signs and symptoms which are then exacerbated by a propagation of excess ovarian androgen production from multiple small follicles, anovulation and insulin resistance in the reproductive life-span, thus setting up a vicious perpetual circle of androgen excess. This opinion paper, rather than being a full-scale review, is intentionally biased in support of this hypothesis that androgen excess is the 'root of all evil' in PCOS; in the hope that its acceptance could lead to more direct treatment of the syndrome in all its facets rather than the symptomatic treatment of side effects of androgen excess that we are addressing today.

  11. Nonlinear roll damping of a barge with and without liquid cargo in spherical tanks

    Directory of Open Access Journals (Sweden)

    Wenhua Zhao

    2016-01-01

    Full Text Available Damping plays a significant role on the maximum amplitude of a vessel's roll motion, in particular near the resonant frequency. It is a common practice to predict roll damping using a linear radiation–diffraction code and add that to a linearized viscous damping component, which can be obtained through empirical, semi-empirical equations or free decay tests in calm water. However, it is evident that the viscous roll damping is nonlinear with roll velocity and amplitude. Nonlinear liquid cargo motions inside cargo tanks also contribute to roll damping, which when ignored impedes the accurate prediction of maximum roll motions. In this study, a series of free decay model tests is conducted on a barge-like vessel with two spherical tanks, which allows a better understanding of the nonlinear roll damping components considering the effects of the liquid cargo motion. To examine the effects of the cargo motion on the damping levels, a nonlinear model is adopted to calculate the damping coefficients. The liquid cargo motion is observed to affect both the linear and the quadratic components of the roll damping. The flow memory effect on the roll damping is also studied. The nonlinear damping coefficients of the vessel with liquid cargo motions in spherical tanks are obtained, which are expected to contribute in configurations involving spherical tanks.

  12. Age and personal values: Similar value circles with shifting priorities.

    Science.gov (United States)

    Borg, Ingwer; Hertel, Guido; Hermann, Dieter

    2017-11-01

    This study examined the relationship of personal values to age using data from two representative surveys. We hypothesized that individuals organize personal values, regardless of their age, as a circle with the same order of values on this circle but that older persons are closer to conservation and more remote from openness to change and closer to self-transcendence and more distant from self-enhancement. The structural stability of the value circle over age was largely confirmed across and within individuals. Different age groups exhibited a tendency to more strongly cluster those values that they rated as relatively important. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Geometric fit of a point set by generalized circles

    DEFF Research Database (Denmark)

    Körner, Mark-Christopher; Brimberg, Jack; Juel, Henrik

    2010-01-01

    In our paper we approximate a set of given points by a general circle. More precisely, given two norms k 1 and k 2 and a set of points in the plane, we consider the problem of locating and scaling the unit circle of norm k 1 such that the sum of weighted distances between the circumference...... of the circle and the given points is minimized, where the distance is measured by a norm k 2. We present results for the general case. In the case that k 1 and k 2 are both polyhedral norms, we are able to solve the problem by investigating a finite candidate set....

  14. Maintenance Appointments in Railway Rolling Stock Rescheduling

    NARCIS (Netherlands)

    J.C. Wagenaar (Joris); L.G. Kroon (Leo); M.E. Schmidt (Marie)

    2016-01-01

    textabstractThis paper addresses the Rolling Stock Rescheduling Problem (RSRP), while taking maintenance appointments into account. After a disruption, the rolling stock of the disrupted passenger trains has to be rescheduled in order to restore a feasible rolling stock circulation. Usually, a

  15. Rolling block mazes are PSPACE-complete

    NARCIS (Netherlands)

    Buchin, K.; Buchin, M.

    2012-01-01

    In a rolling block maze, one or more blocks lie on a rectangular board with square cells. In most mazes, the blocks have size k × m × n where k, m, n are integers that determine the size of the block in terms of units of the size of the board cells. The task of a rolling block maze is to roll a

  16. Efficient Circulation of Railway Rolling Stock

    NARCIS (Netherlands)

    Alfieri, A.; Groot, R.; Kroon, L.G.; Schrijver, A.

    2006-01-01

    Railway rolling stock (locomotives, carriages, and train units) is one of the most significant cost sources for operatorsof passenger trains, both public and private. Rolling stock costsare due to material acquisition, power supply, and material maintenance. The efficient circulation of rolling

  17. Peer Evaluation of Master Programs: Closing the Quality Circle of the CDIO Approach?

    DEFF Research Database (Denmark)

    Hussmann, Peter Munkebo; Bisi, Anita; Malmqvist, Johan

    2012-01-01

    programs within their field at another N5T institution. The article describes the quality enhancement tool in detail, its contribution to the development of the involved programs, and how international peer evaluation can contribute to closing the quality circle. Finally, it assesses the value......A quality assurance project was conducted within the framework of the Nordic Five Tech Alliance (N5T), a strategic alliance of the five leading technical universities in Denmark, Finland, Norway, and Sweden. The project concerned the development of a common quality enhancement tool for conducting...... peer evaluations of educational programs to enable their further development and close the quality circle. In addition, the project will contribute to the consolidation of the N5T alliance by facilitating contacts between faculty members and providing them with an in-depth knowledge of the study...

  18. Design of a Small Scale Roll to Roll Device

    OpenAIRE

    Pereira, Amon A; White, Edward; Kramer, Rebecca Krone

    2014-01-01

    In the soft robotics field, hyperelastic polymer films are used in conjunction with eutectic gallium indium to create flexible strain gages. However, rapid large scale manufacturing methods of such sensors have yet to be developed. Developing new manufacturing methods will allow for researchers to build and test new soft sensor concepts faster but also pave the way for future mass-production of these sensors for consumer or industrial consumption. One of those methods would be a Roll to...

  19. Perovskite solar cells for roll-to-roll fabrication

    Directory of Open Access Journals (Sweden)

    Uddin Ashraf

    2017-01-01

    Full Text Available Perovskite solar cell (PSCs is considered as the game changer in emerging photovoltaics technology. The highest certified efficiency is 22% with high temperature processed (∼500 °C TiO2 based electron transport layer (ETL. High temperature process is a rudimentary hindrance towards roll-to-roll processing of PSCs on flexible substrates. Low temperature solution process (<150 °C ZnO based ETL is one of the most promising candidate for large scale roll-to-roll fabrication of cells as it has nearly identical electron affinity (4.2 eV of TiO2. The mixed organic perovskite (MA0.6FA0.4PbI3 devices with Al doped ZnO (AZO ETL demonstrate average cell efficiency over 16%, which is the highest ever reported efficiency for this device configuration. The energy level alignment and related interfacial charge transport dynamics at the interface of ZnO and perovskite films and the adjacent charge transport layers are investigated. Significantly improved device stability, hysteresis free device photocurrent have been observed in MA0.6FA0.4PbI3 cells. A systematic electrochemical impedance spectroscopy, frequency dependent capacitance spectra, surface morphology and topography characterization have been conducted to understand the role of interfacial electronic properties between perovskite and neighbouring layers in perovskite device. A standardized degradation study, interfacial electronic property and capacitive spectra analysis of aged device, have been measured to understand the enhanced device stability in mixed MA0.6FA0.4PbI3 cells. Slow perovskite material decomposition rate and augmented device lifetime with AZO based devices have been found to be correlated with the more hydrophobic and acidic nature of AZO surface compared to pristine ZnO film.

  20. Parhelic-like circle from light scattering in Plateau borders

    Energy Technology Data Exchange (ETDEWEB)

    Tufaile, A., E-mail: tufaile@usp.br; Tufaile, A.P.B.

    2015-03-06

    We are reporting a new simple optical element to generate halos. We have observed interesting patterns of light scattering in Plateau borders in foams. In analogy to the atmospheric phenomena known as parhelic circle, sun dogs, and sun pillars, we have named the features of the patterns observed as parlaseric circle, laser dogs, and laser pillars. The triangular symmetry of the Plateau borders is analogous to the hexagonal symmetry of ice crystals which produce these atmospheric phenomena. Working with one Plateau border at a time, we have observed wave optics phenomena that are not perceived in the atmospheric phenomena, such as diffraction and interference. - Highlights: • We obtained halo formation from light scattering in a Plateau border using an experiment. • We explained halo formation using geometrical theory of diffraction. • An optical element based on a Plateau border is proposed. • We compared some aspects of the parhelic circle with the parlaseric circle.

  1. Quality Productivity Circle in Manufacture | Achi | Nigerian Journal of ...

    African Journals Online (AJOL)

    A brief history of quality control and productivity is hereby traced. ... Circle management technique are discussed in its relationship with productivity. ... so should be made sound in body (and spirit) through appropriate training and motivation.

  2. Research Circles - a method for developing guidance practices

    DEFF Research Database (Denmark)

    2012-01-01

    This video reports on our work with using research circles to improve our understanding of how to provide guidance and counseling to help young people in danger of dropping out of school. The video is based on the paper: Research Circles -- a method for developing guidance practices, and was pres......This video reports on our work with using research circles to improve our understanding of how to provide guidance and counseling to help young people in danger of dropping out of school. The video is based on the paper: Research Circles -- a method for developing guidance practices......, and was presented at the Conference for Social Justice, Prosperity and Sustainable Employment 2012 by assistant professor Helle Merete Nordentoft from DPU (http://edu.au.dk/). The film communicating the research paper was created by Mie Nørgaard...

  3. Squaring the Circle: Attempting Peace in Northern Ireland

    National Research Council Canada - National Science Library

    Marchi, Gina

    1997-01-01

    Finding a political framework for self-government in Northern Ireland that will be supported by both nationalists and unionists is referred to as a modern day attempt to do the impossible-to 'square the circle...

  4. On the constant-roll inflation

    Science.gov (United States)

    Yi, Zhu; Gong, Yungui

    2018-03-01

    The primordial power spectra of scalar and tensor perturbations during slow-roll inflation are usually calculated with the method of Bessel function approximation. For constant-roll or ultra slow-roll inflation, the method of Bessel function approximation may be invalid. We compare the numerical results with the analytical results derived from the Bessel function approximation, and we find that they differ significantly on super-horizon scales if the constant slow-roll parameter ηH is not small. More accurate method is needed for calculating the primordial power spectrum for constant-roll inflation.

  5. Improved Dutch Roll Approximation for Hypersonic Vehicle

    Directory of Open Access Journals (Sweden)

    Liang-Liang Yin

    2014-06-01

    Full Text Available An improved dutch roll approximation for hypersonic vehicle is presented. From the new approximations, the dutch roll frequency is shown to be a function of the stability axis yaw stability and the dutch roll damping is mainly effected by the roll damping ratio. In additional, an important parameter called roll-to-yaw ratio is obtained to describe the dutch roll mode. Solution shows that large-roll-to-yaw ratio is the generate character of hypersonic vehicle, which results the large error for the practical approximation. Predictions from the literal approximations derived in this paper are compared with actual numerical values for s example hypersonic vehicle, results show the approximations work well and the error is below 10 %.

  6. Membandingkan Bilangan Pecahan Menggunakan Fraction Circle terhadap Pemahaman Konsep Siswa

    Directory of Open Access Journals (Sweden)

    Renny Sendra Wahyuni

    2017-03-01

    Full Text Available Penelitian bertujuan untuk mendeskripsikan lintasan belajar siswa dalam memahami konsep pembelajaran membandingkan bilangan pecahan dengan menggunakan fraction circle melalui pendekatan PMRI. Penelitian dilaksanakan di SD Negeri 146 Palembang. Metode yang digunakan adalah design research melalui tahap-tahap preparing for the experiment, teaching experiment, dan retrospective analysis. Penelitian ini menunjukkan peranan fraction circle sebagai model yang mendorong peserta didik menemukan pemahaman konsep membandingkan bilangan pecahan dengan menggunakan pendekatan PMRI. Kata Kunci: pecahan, fraction circle, design research, PMRI This study aims to design a learning trajectory to help students understand the concept of rational numbers through fashion context. The study aims to describe students learning trajectory in understanding the concept of comparing fractions through fraction circle with PMRI approach. The research was conducted in SD Negeri 146 Palembang. The method used in this research is design research which consists of three stages: preparing for the experiment, teaching experiment, and retrospective analysis. The result shows the role fraction circle as a model to encourage students to understand the concept of comparing fractions using PMRI approach. Keywords: fractions, fraction circle, design research, PMRI

  7. Circles South East: the first 10 years 2002-2012.

    Science.gov (United States)

    Bates, Andrew; Williams, Dominic; Wilson, Chris; Wilson, Robin J

    2014-07-01

    This article describes the first 10 years of the implementation of Circles of Support and Accountability (Circles) in the management of sexual offenders in South-East England by Circles South East (CSE). The Circles of 71 core members are reviewed in detail, with reference to demographic data, offense and sentencing histories, risk assessment data, and considerations regarding Multi-Agency Public Protection Arrangements. A group of 71 comparison subjects who were referred to CSE and deemed suitable for but did not receive the service was identified. Follow-up behaviors of both groups are examined (including all forms of reconviction, breach of orders, and prison recall). Over a comparable follow-up period of 55 months, the incidence of violent and contact sexual reconviction in the comparison group was significantly higher than for the Circles cohort. Comparisons are made between expected and actual levels of sexual reconviction, with the Circles cohort showing lower than expected rate of sexual reconviction but not to a statistically significant degree. © The Author(s) 2013.

  8. Tachyon constant-roll inflation

    Science.gov (United States)

    Mohammadi, A.; Saaidi, Kh.; Golanbari, T.

    2018-04-01

    The constant-roll inflation is studied where the inflaton is taken as a tachyon field. Based on this approach, the second slow-roll parameter is taken as a constant which leads to a differential equation for the Hubble parameter. Finding an exact solution for the Hubble parameter is difficult and leads us to a numerical solution for the Hubble parameter. On the other hand, since in this formalism the slow-roll parameter η is constant and could not be assumed to be necessarily small, the perturbation parameters should be reconsidered again which, in turn, results in new terms appearing in the amplitude of scalar perturbations and the scalar spectral index. Utilizing the numerical solution for the Hubble parameter, we estimate the perturbation parameter at the horizon exit time and compare it with observational data. The results show that, for specific values of the constant parameter η , we could have an almost scale-invariant amplitude of scalar perturbations. Finally, the attractor behavior for the solution of the model is presented, and we determine that the feature could be properly satisfied.

  9. Three Concentric Circles: Young Chinese English Learners' Perceptions of Purposeful Audiences

    Science.gov (United States)

    Liu, Jack Jinghui

    2015-01-01

    English learners have more access to communicate with different purposeful audiences across the Three Concentric Circles of English (Kachu, 1985): the Inner Circle, the Outer Circle and the Expanding Circle. However, young language learners' purposeful audience as a focus of communication has not been emphasized as much as other linguistic…

  10. Impact of a learning circle intervention across academic and service contexts on developing a learning culture.

    Science.gov (United States)

    Walker, Rachel; Henderson, Amanda; Cooke, Marie; Creedy, Debra

    2011-05-01

    Partnerships between university schools of nursing and health services lead to successful learning experiences for students and staff. A purposive sample of academics and students from a university school of nursing and clinicians from three health institutions involved in clinical learning (n=73) actively participated in a learning circles intervention conducted over 5 months in south east Queensland. Learning circle discussions resulted in enhanced communication and shared understanding regarding: (1) staff attitudes towards students, expectations and student assessment; (2) strategies enhancing preparation of students, mechanisms for greater support of and recognition of clinicians; (3) challenges faced by staff in the complex processes of leadership in clinical nursing education; (4) construction of learning, ideas for improving communication, networking and sharing; and (5) questioning routine practices that may not enhance student learning. Pre-post surveys of hospital staff (n=310) revealed significant differences across three sub-scales of 'accomplishment' (t=-3.98, pLearning circles can positively enhance organisational learning culture. The intervention enabled participants to recognise mutual goals. Further investigation around staff perception of their influence on their workplace is required. Copyright © 2010 Elsevier Ltd. All rights reserved.

  11. Three-charge black holes on a circle

    International Nuclear Information System (INIS)

    Harmark, Troels; Obers, Niels A.; Roenne, Peter B.; Kristjansson, Kristjan R.

    2007-01-01

    We study phases of five-dimensional three-charge black holes with a circle in their transverse space. In particular, when the black hole is localized on the circle we compute the corrections to the metric and corresponding thermodynamics in the limit of small mass. When taking the near-extremal limit, this gives the corrections to the finite entropy of the extremal three-charge black hole as a function of the energy above extremality. For the partial extremal limit with two charges sent to infinity and one finite we show that the first correction to the entropy is in agreement with the microscopic entropy by taking into account that the number of branes shift as a consequence of the interactions across the transverse circle. Beyond these analytical results, we also numerically obtain the entire phase of non- and near-extremal three- and two-charge black holes localized on a circle. More generally, we find in this paper a rich phase structure, including a new phase of three-charge black holes that are non-uniformly distributed on the circle. All these three-charge black hole phases are found via a map that relates them to the phases of five-dimensional neutral Kaluza-Klein black holes

  12. Talking Circles for Adolescent Girls in an Urban High School

    Directory of Open Access Journals (Sweden)

    Ann Schumacher

    2014-10-01

    Full Text Available Restorative Practices (RP in schools is a new and emerging field. Meeting in Circles to build friendships, develop emotional literacy skills, resolve conflict, or learn interactively are some of the core components of these programs. This article describes a 2-year study of 12 weekly Talking Circles organized under the auspices of a RP program in an urban high school with 60 adolescent girls. Primary data sources included 257 hr of participant observations in Talking Circles and individual, semi-structured interviews with 31 students. The Relational Cultural model, rooted in the work of Jean Baker Miller, served as the conceptual framework for understanding teens’ interactions within the Circle’s unique set of social conditions in a school environment. Findings demonstrated that Talking Circles provided a safe space for peers helping peers, and that the girls improved their listening, anger management, and empathic skills, which led to greater self-efficacy. It appears that Talking Circles could provide another venue for developing social-emotional literacy skills and growth-fostering relationships in schools.

  13. [A design of refractometer based on blur circle].

    Science.gov (United States)

    Zhang, Yikui; Huang, Shenghai; Ye, Huifang; Zou, Ruitao; Tong, Gengmin; Zhuo, Ran

    2011-03-01

    Design a convenient and stable eye refractometer based on the theory of blur circle. Analyze the retinal blur circle in both Emsly reduced eye model and Liou & Brennan 1997 eye model by ZEMAX. Design the coefficients including PD (pupil diameter) and NO' (length between node point and fovea) with the purpose of improving the accuracy. At last, compare the clinical optometry data from this refractor with the data obtained from optometry hospital in Wenzhou. The blur circle diameters are nearly the same in both reduced eye model and the Liou & Brennan 1997 eye model. With the PD = 4 mm and NO' = 20 mm, the refractor shows a fine accuracy in optometry. The paired t test shows that the myopia group and the astigmatism axial direction group have no statistical difference between the data from the blur circle refractor and the hospital (P > 0.05), while the astigmatism degree group has the result of P = 0.41 which may be caused by the poor cooperation of pediatric patients. 80% of the astigmatism degree data differ from the data from the hospital in less than 0.75D. The blur circle refractor, with the features of convenience and fine accuracy, is promised to be a new style of refractometer in the future.

  14. Effect of stern hull shape on turning circle of ships

    Science.gov (United States)

    Jaswar, Maimun, A.; Wahid, M. A.; Priyanto, A.; Zamani, Pauzi, Saman

    2012-06-01

    Many factors such as: stern hull shape, length, draught, trim, propulsion system and external forces affecting the drift angle influence rate of turn and size of turning circle of ships. This paper discusses turning circle characteristics of U and V stern hull shape of Very Large Crude Oil Carrier (VLCC) ships. The ships have same principal dimension such as length, beam, and draught. The turning circle characteristics of the VLCC ships are simulated at 35 degree of rudder angle. In the analysis, firstly, turning circle performance of U-type VLCC ship is simulated. In the simulation, initial ship speed is determined using given power and rpm. Hydrodynamic derivatives coefficients are determined by including effect of fullness of aft run. Using the obtained, speed and hydrodynamic coefficients, force and moment acting on hull, force and moment induced by propeller, force and moment induced by rudder are determined. Finally, ship trajectory, ratio of speed, yaw angle and drift angle are determined. Results of simulation results of the VLCC ship are compared with the experimental one as validation. Using the same method, V-type VLCC is simulated and the simulation results are compared with U-type VLCC ship. Results shows the turning circle of U-type is larger than V-type due to effect stern hul results of simulation are.

  15. Fluid management in roll-to-roll nanoimprint lithography

    Science.gov (United States)

    Jain, A.; Bonnecaze, R. T.

    2013-06-01

    The key process parameters of UV roll-to-roll nanoimprint lithography are identified from an analysis of the fluid, curing, and peeling dynamics. The process includes merging of droplets of imprint material, curing of the imprint material from a viscous liquid to elastic solid resist, and pattern replication and detachment of the resist from template. The time and distances on the web or rigid substrate over which these processes occur are determined as function of the physical properties of the uncured liquid, the cured solid, and the roller configuration. The upper convected Maxwell equation is used to model the viscoelastic liquid and to calculate the force on the substrate and the torque on the roller. The available exposure time is found to be the rate limiting parameter and it is O(√Rho /uo), where R is the radius of the roller, ho is minimum gap between the roller and web, and uo is the velocity of the web. The residual layer thickness of the resist should be larger than the gap between the roller and the substrate to ensure complete feature filling and optimal pattern replication. For lower residual layer thickness, the droplets may not merge to form a continuous film for pattern transfer.

  16. The real time rolling shutter

    OpenAIRE

    Monaghan, David; O'Connor, Noel E.; Cleary, Anne; Connolly, Denis

    2015-01-01

    From an early age children are often told either, you are creative you should do art but stay away from science and maths. Or that you are mathematical you should do science but you're not that creative. Compounding this there also exist some traditional barriers of artistic rhetoric that say, "don't touch, don't think and don't be creative, we've already done that for you, you can just look...". The Real Time Rolling Shutter is part of a collaborative Art/Science partnership whose core tenet...

  17. Grooved tube plug rolls in

    International Nuclear Information System (INIS)

    Krausser, P.

    1991-01-01

    The removable plugs used to date by the Power Generation Group (KWU) of Siemens to seal defective steam generator tubes have a good track record. Their sealing principle is based on the elastic tensioning of three seal disks against the inside wall of the tube. Now a further removable plug is available -a roll-in plug with a metal-coated surface. It is particularly suitable for use in the roller-expanded zone of the tubes at the tube sheet. The plugs can be used in both Siemens-KWU steam generators and in steam generators manufactured in compliance with the guidelines of the ASME Code. (author)

  18. ROLL OUT THE TALENT : Final project report

    OpenAIRE

    Eerola, Tuomas; Tuominen, Pirjo; Hakkarainen, Riitta-Liisa; Laurikainen, Marja; Mero, Niina

    2014-01-01

    The ROLL OUT THE TALENT project was born out of the desire to recognise and support the strengths of vocational students and to develop new and innovative operating models. ROLL OUT THE TALENT promoted regional cooperation between institutes and companies. The project produced operating and study path models that take into consideration the individual strengths of vocational students and the principles of lifelong learning. This is the final report of the ROLL OUT THE TALENT project, and ...

  19. Interlayer adhesion in roll-to-roll processed flexible inverted polymer solar cells

    KAUST Repository

    Dupont, Stephanie R.; Oliver, Mark; Krebs, Frederik C.; Dauskardt, Reinhold H.

    2012-01-01

    The interlayer adhesion of roll-to-roll processed flexible inverted P3HT:PCBM bulk heterojunction (BHJ) polymer solar cells is reported. Poor adhesion between adjacent layers may result in loss of device performance from delamination driven

  20. Radiometric study of creep in ingot rolling

    International Nuclear Information System (INIS)

    Kubicek, P.; Zamyslovsky, Z.; Uherek, J.

    The radiometric study of creep during ingot rolling performed in the rolling mill of the Vitkovice Iron and Steel Works and the first results are described. Selected sites in 3 to 8 ton ingots were labelled with 2 to 3.7x10 5 Bq of 60 Co and after rolling into blocks, the transposition of the labelled sites of the ingots was investigated. The results indicate creep during rolling, local extension in certain sites under study and help to determine the inevitable bottom crop incurred in the forming. Finally, the requirements put on the radiometric apparatus for the next stages of technological research are presented. (author)

  1. METHOD OF HOT ROLLING URANIUM METAL

    Science.gov (United States)

    Kaufmann, A.R.

    1959-03-10

    A method is given for quickly and efficiently hot rolling uranium metal in the upper part of the alpha phase temperature region to obtain sound bars and sheets possessing a good surface finish. The uranium metal billet is heated to a temperature in the range of 1000 deg F to 1220 deg F by immersion iii a molten lead bath. The heated billet is then passed through the rolls. The temperature is restored to the desired range between successive passes through the rolls, and the rolls are turned down approximately 0.050 inch between successive passes.

  2. A comparative study of roll compaction of free-flowing and cohesive pharmaceutical powders.

    Science.gov (United States)

    Yu, Shen; Gururajan, Bindhu; Reynolds, Gavin; Roberts, Ron; Adams, Michael J; Wu, Chuan-Yu

    2012-05-30

    Roll compaction is widely adopted as a dry granulation method in the pharmaceutical industry. The roll compaction behaviour of feed powders is primarily governed by two parameters: the maximum pressure and the nip angle. Although the maximum pressure can be measured directly using pressure sensors fitted in the rolls, it is not a trivial task to determine the nip angle, which is a measure of the size of the compaction zone and hence the degree of compression. Thus a robust approach based upon the calculation of the pressure gradient, which can be obtained directly from experiments using an instrumented roll compactor, was developed. It has been shown that the resulting nip angles are comparable to those obtained using the methods reported in literature. Nevertheless, the proposed approach has distinctive advantages including (1) it is based on the intrinsic features of slip and no-slip interactions between the powder and roll surface and (2) it is not necessary to carry out wall friction measurements that involve plates that may not be representative of the roll compactor in terms of the surface topography and surface energy. The method was evaluated by investigating the effect of roll speed for two pharmaceutical excipients with distinctive material properties: microcrystalline cellulose (MCC) and di-calcium phosphate dihydrate (DCPD). It was found that the maximum pressure and nip angle for DCPD, which is a cohesive powder, decrease sharply with increasing roll speed whereas they are essentially independent of roll speed for MCC, which is an easy flowing powder. The roll compaction behaviour of MCC-DCPD mixtures with various compositions was also investigated in order to evaluate the effect of flowability. It was found that the nip angle and maximum pressure generally increased with improved flowability of the feed powders. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Fabrication of cold-rolled bands of the alloy-ehi 702 in rolls

    International Nuclear Information System (INIS)

    Zhuchin, V.N.; Gindin, A.Sh.; Shaburov, V.E.; Vladimirov, S.M.; Sokolov, V.A.; Shavkun, V.V.; Perepelitsa, I.V.; Markov, V.V.; Naymov, E.P.; Evstaf'ev, P.P.

    1977-01-01

    The questions are discussed, connected with the manufacture of cold-rolled strip of alloy EI702 in reels from strip blanks. It has been established that in the manufacture of hot-rolled stock from EI702 slabs it is necessary to use powerful rolling equipment because of high resistance to deformation. The reel method for manufacturing EI702 alloy improves the rolled stock and increases percentage of serviceable stock, as well as the output

  4. Rolling into spatial disorientation: Simulator demonstration of the post-roll (Gillingham) illusion

    NARCIS (Netherlands)

    Nooij, S.A.E.; Groen, E.L.

    2011-01-01

    Introduction: Spatial disorientation (SD) is still a contributing factor in many aviation accidents, stressing the need for adequate SD training scenarios. In this article we focused on the post-roll effect (the sensation of rolling back after a roll maneuver, such as an entry of a coordinated turn)

  5. Circles Disturbed The Interplay of Mathematics and Narrative

    CERN Document Server

    Doxiadis, Apostolos

    2012-01-01

    Circles Disturbed brings together important thinkers in mathematics, history, and philosophy to explore the relationship between mathematics and narrative. The book's title recalls the last words of the great Greek mathematician Archimedes before he was slain by a Roman soldier--"Don't disturb my circles"--words that seem to refer to two radically different concerns: that of the practical person living in the concrete world of reality, and that of the theoretician lost in a world of abstraction. Stories and theorems are, in a sense, the natural languages of these two worlds--stories represent

  6. The core of C*-algebras associated with circle maps

    DEFF Research Database (Denmark)

    Johannesen, Benjamin Randeris

    2017-01-01

    The relationship between dynamical systems and operator algebras is one that has been fruitful and mutually beneficial and is by now both well-established, -aged and -matured. This thesis contribute in developing the relationship between dynamical systems, groupoids and operator algebra for circle...... dynamics. Another aspect of this thesis are the results solely about dynamics on the unit circle. The reader is supposed to be well versed in C*-algebras and K-theory (and classification). The reader is not assumed to be familiar with dynamical system theory nor with groupoids....

  7. The Existence and Structure of Rotational Systems in the Circle

    OpenAIRE

    Ramanathan, Jayakumar

    2018-01-01

    By a rotational system, we mean a closed subset X of the circle, T=R/Z, together with a continuous transformation f:X→X with the requirements that the dynamical system (X,f) be minimal and that f respect the standard orientation of T. We show that infinite rotational systems (X,f), with the property that map f has finite preimages, are extensions of irrational rotations of the circle. Such systems have been studied when they arise as invariant subsets of certain specific mappings, F:T→T. Beca...

  8. CP violation in Z circle → τ+τ-

    International Nuclear Information System (INIS)

    Lopez, J.M.

    1998-01-01

    Test of CP invariance in the reaction Z circle → τ + τ - on the Z circle peak is performed using the data sample recorded by the four Collaboration at LEP and SLD. From the non-observation of CP violation upper limits on the real (vertical stroke Re(d r W ) vertical stroke) and imaginary (vertical stroke Im(d r W ) vertical stroke) parts of the weak dipole moment of the τ lepton at 95% C.L. are derived. Results on measurements on weak magnetic moment is also reported. (orig.)

  9. A simple algorithm for computing the smallest enclosing circle

    DEFF Research Database (Denmark)

    Skyum, Sven

    1991-01-01

    Presented is a simple O(n log n) algorithm for computing the smallest enclosing circle of a convex polygon. It can be easily extended to algorithms that compute the farthest-and the closest-point Voronoi diagram of a convex polygon within the same time bound.......Presented is a simple O(n log n) algorithm for computing the smallest enclosing circle of a convex polygon. It can be easily extended to algorithms that compute the farthest-and the closest-point Voronoi diagram of a convex polygon within the same time bound....

  10. Environmental Assessment: Disposition of Chiefs’ Circle Residential Structures

    Science.gov (United States)

    2012-04-27

    five structures ranged from Page 4 of 5  $200,000 (with bricks removed) to $500,000 (with bricks intact). Mike Ford, CEO of NewTown Macon, echoed Mr...feasibility 25-Jul-08 and practicality of moving the Chief’s Circle duplexes Mike Ford NewTown Macon 23-Jul-08 478-722-9909 President of NewTown Macon...Daniel.Chavira@ Gave a tour of Chiefs’ Circle huntcompanies.com Not interested in using the houses Bob Sharples RAFB 26-Oct-10 robert.sharples

  11. The "Dot in Circle" Sign on MRI in Maduramycosis: A Characteristic Finding

    Directory of Open Access Journals (Sweden)

    Vikash Jain

    2012-01-01

    Full Text Available Mycetoma or Maduramycosis is a localized chronic suppurative infection characterized by exuberant granulation tissue, discharging sinuses, and bone involvement later in the course of the disease. Early clinical diagnosis before the appearance of sinuses and grains (aggregates of organism surrounded by granulation tissue, which are discharged from the draining sinuses is difficult. Delay in diagnosis may lead to amputation of the affected part. Definitive diagnosis is through biopsy and microbiological examination. However, at times diagnosis may still be difficult. The recently described "dot in circle" sign on magnetic resonance imaging (MRI is easy to recognize and highly specific. We present a case of mycetoma foot with characteristic MRI features.

  12. Quantification of rolling circle amplified DNA using magnetic nanobeads and a Blu-ray optical pick-up unit

    DEFF Research Database (Denmark)

    Donolato, Marco; Antunes, Paula Soares Martins; Gómez del a Torre, Teresa Zardán

    2015-01-01

    the optimum magnetic bead concentration to 0.1 mg/mL and have measured the response vs. concentration of DNA coils formed from Escherichia Coli. We have found a limit of detection of 10 pM and a dynamic range of about two orders of magnitude, which is comparable to the performance obtained using costly...

  13. On-Particle Rolling Circle Amplification-Based Core-Satellite Magnetic Superstructures for MicroRNA Detection

    DEFF Research Database (Denmark)

    Tian, Bo; Qiu, Zhen; Ma, Jing

    2018-01-01

    -specific nuclease in the presence of target microRNA, resulting in a release of MNPs that can be quantified in an optomagnetic sensor. The proposed biosensor has a simple mix-separate-measure strategy. For let-7b detection, the proposed biosensor offers a wide linear detection range of approximately 5 orders...

  14. Deformation in Micro Roll Forming of Bipolar Plate

    Science.gov (United States)

    Zhang, P.; Pereira, M.; Rolfe, B.; Daniel, W.; Weiss, M.

    2017-09-01

    Micro roll forming is a new processing technology to produce bipolar plates for Proton Exchange Membrane Fuel Cells (PEMFC) from thin stainless steel foil. To gain a better understanding of the deformation of the material in this process, numerical studies are necessary before experimental implementation. In general, solid elements with several layers through the material thickness are required to analyse material thinning in processes where the deformation mode is that of bending combined with tension, but this results in high computational costs. This pure solid element approach is especially time-consuming when analysing roll forming processes which generally involves feeding a long strip through a number of successive roll stands. In an attempt to develop a more efficient modelling approach without sacrificing accuracy, two solutions are numerically analysed with ABAQUS/Explicit in this paper. In the first, a small patch of solid elements over the strip width and in the centre of the “pre-cut” sheet is coupled with shell elements while in the second approach pure shell elements are used to discretize the full sheet. In the first approach, the shell element enables accounting for the effect of material being held in the roll stands on material flow while solid elements can be applied to analyse material thinning in a small discrete area of the sheet. Experimental micro roll forming trials are performed to prove that the coupling of solid and shell elements can give acceptable model accuracy while using shell elements alone is shown to result in major deviations between numerical and experimental results.

  15. Types of the cerebral arterial circle (circle of Willis in a Sri Lankan Population

    Directory of Open Access Journals (Sweden)

    Gunasekera WSL

    2011-01-01

    Full Text Available Abstract Background The variations of the circle of Willis (CW are clinically important as patients with effective collateral circulations have a lower risk of transient ischemic attack and stroke than those with ineffective collaterals. The aim of the present cadaveric study was to investigate the anatomical variations of the CW and to compare the frequency of prevalence of the different variations with previous autopsy studies as variations in the anatomy of the CW as a whole have not been studied in the Indian subcontinent. Methods The external diameter of all the arteries forming the CW in 225 normal Sri Lankan adult cadaver brains was measured using a calibrated grid to determine the prevalence in the variation in CW. Chisquared tests and a correspondence analysis were performed to compare the relative frequencies of prevalence of anatomical variations in the CW across 6 studies of diverse ethnic populations. Results We report 15 types of variations of CW out of 22 types previously described and one additional type: hypoplastic precommunicating part of the anterior cerebral arteries (A1 and contralateral posterior communicating arteries (PcoA 5(2%. Statistically significant differences (p Conclusion The present study reveals that there are significant variations in the CW among intra and inter ethnic groups (Caucasian, African and Asian: Iran and Sri Lanka dominant populations, and warrants further studies keeping the methods of measurements, data assessment, and the definitions of hypoplasia the same.

  16. Roll forming of eco-friendly stud

    Science.gov (United States)

    Keum, Y. T.; Lee, S. Y.; Lee, T. H.; Sim, J. K.

    2013-12-01

    In order to manufacture an eco-friendly stud, the sheared pattern is designed by the Taguchi method and expanded by the side rolls. The seven geometrical shape of sheared pattern are considered in the structural and thermal analyses to select the best functional one in terms of the durability and fire resistance of dry wall. For optimizing the size of the sheared pattern chosen, the L9 orthogonal array and smaller-the-better characteristics of the Taguchi method are used. As the roll gap causes forming defects when the upper-and-lower roll type is adopted for expanding the sheared pattern, the side roll type is introduced. The stress and strain distributions obtained by the FEM simulation of roll-forming processes are utilized for the design of expanding process. The expanding process by side rolls shortens the length of expanding process and minimizes the cost of dies. Furthermore, the stud manufactured by expanding the sheared pattern of the web is an eco-friend because of the scrapless roll-forming process. In addition, compared to the conventionally roll-formed stud, the material cost is lessened about 13.6% and the weight is lightened about 15.5%.

  17. Pipe Rolling from Continuous Cast Metal

    International Nuclear Information System (INIS)

    Zhordania, I.; Chkhartishvili, I.; Lordkipanidze, J.; Melashvili, Z.; Papava, K.; Khundadze, K.

    2007-01-01

    The approach to manufacturing of high quality pipes as a result of solid and hollow billet rolling from continuous cast metal is shown. Optimal parameters of piercing, temperature of piercing and piercing rolling mill rollers speed have been experimentally established. (author)

  18. Numerical analysis of Swiss roll metamaterials

    International Nuclear Information System (INIS)

    Demetriadou, A; Pendry, J B

    2009-01-01

    A Swiss roll metamaterial is a resonant magnetic medium, with a negative magnetic permeability for a range of frequencies, due to its self-inductance and self-capacitance components. In this paper, we discuss the band structure, S-parameters and effective electromagnetic parameters of Swiss roll metamaterials, with both analytical and numerical results, which show an exceptional convergence.

  19. Efficient Circulation of Railway Rolling Stock

    NARCIS (Netherlands)

    A. Alfieri (Arianna); R. Groot (Rutger); L.G. Kroon (Leo); A. Schrijver (Lex)

    2002-01-01

    textabstractRailway rolling stock (locomotives, carriages, and train units) is one of the most significant cost sources for operatorsof passenger trains, both public and private. Rolling stock costsare due to material acquisition, power supply, and material maintenance. The efficient circulation of

  20. [Does implementation of benchmarking in quality circles improve the quality of care of patients with asthma and reduce drug interaction?].

    Science.gov (United States)

    Kaufmann-Kolle, Petra; Szecsenyi, Joachim; Broge, Björn; Haefeli, Walter Emil; Schneider, Antonius

    2011-01-01

    The purpose of this cluster-randomised controlled trial was to evaluate the efficacy of quality circles (QCs) working either with general data-based feedback or with an open benchmark within the field of asthma care and drug-drug interactions. Twelve QCs, involving 96 general practitioners from 85 practices, were randomised. Six QCs worked with traditional anonymous feedback and six with an open benchmark. Two QC meetings supported with feedback reports were held covering the topics "drug-drug interactions" and "asthma"; in both cases discussions were guided by a trained moderator. Outcome measures included health-related quality of life and patient satisfaction with treatment, asthma severity and number of potentially inappropriate drug combinations as well as the general practitioners' satisfaction in relation to the performance of the QC. A significant improvement in the treatment of asthma was observed in both trial arms. However, there was only a slight improvement regarding inappropriate drug combinations. There were no relevant differences between the group with open benchmark (B-QC) and traditional quality circles (T-QC). The physicians' satisfaction with the QC performance was significantly higher in the T-QCs. General practitioners seem to take a critical perspective about open benchmarking in quality circles. Caution should be used when implementing benchmarking in a quality circle as it did not improve healthcare when compared to the traditional procedure with anonymised comparisons. Copyright © 2011. Published by Elsevier GmbH.

  1. Constant-roll (quasi-)linear inflation

    Science.gov (United States)

    Karam, A.; Marzola, L.; Pappas, T.; Racioppi, A.; Tamvakis, K.

    2018-05-01

    In constant-roll inflation, the scalar field that drives the accelerated expansion of the Universe is rolling down its potential at a constant rate. Within this framework, we highlight the relations between the Hubble slow-roll parameters and the potential ones, studying in detail the case of a single-field Coleman-Weinberg model characterised by a non-minimal coupling of the inflaton to gravity. With respect to the exact constant-roll predictions, we find that assuming an approximate slow-roll behaviour yields a difference of Δ r = 0.001 in the tensor-to-scalar ratio prediction. Such a discrepancy is in principle testable by future satellite missions. As for the scalar spectral index ns, we find that the existing 2-σ bound constrains the value of the non-minimal coupling to ξphi ~ 0.29–0.31 in the model under consideration.

  2. Analytical method for establishing indentation rolling resistance

    Directory of Open Access Journals (Sweden)

    Gładysiewicz Lech

    2018-01-01

    Full Text Available Belt conveyors are highly reliable machines able to work in special operating conditions. Harsh environment, long distance of transporting and great mass of transported martials are cause of high energy usage. That is why research in the field of belt conveyor transportation nowadays focuses on reducing the power consumption without lowering their efficiency. In this paper, previous methods for testing rolling resistance are described, and new method designed by authors was presented. New method of testing rolling resistance is quite simple and inexpensive. Moreover it allows to conduct the experimental tests of the impact of different parameters on the value of indentation rolling resistance such as core design, cover thickness, ambient temperature, idler travel frequency, or load value as well. Finally results of tests of relationship between rolling resistance and idler travel frequency and between rolling resistance and idler travel speed was presented.

  3. Analytical method for establishing indentation rolling resistance

    Science.gov (United States)

    Gładysiewicz, Lech; Konieczna, Martyna

    2018-01-01

    Belt conveyors are highly reliable machines able to work in special operating conditions. Harsh environment, long distance of transporting and great mass of transported martials are cause of high energy usage. That is why research in the field of belt conveyor transportation nowadays focuses on reducing the power consumption without lowering their efficiency. In this paper, previous methods for testing rolling resistance are described, and new method designed by authors was presented. New method of testing rolling resistance is quite simple and inexpensive. Moreover it allows to conduct the experimental tests of the impact of different parameters on the value of indentation rolling resistance such as core design, cover thickness, ambient temperature, idler travel frequency, or load value as well. Finally results of tests of relationship between rolling resistance and idler travel frequency and between rolling resistance and idler travel speed was presented.

  4. New perspectives on constant-roll inflation

    Science.gov (United States)

    Cicciarella, Francesco; Mabillard, Joel; Pieroni, Mauro

    2018-01-01

    We study constant-roll inflation using the β-function formalism. We show that the constant rate of the inflaton roll is translated into a first order differential equation for the β-function which can be solved easily. The solutions to this equation correspond to the usual constant-roll models. We then construct, by perturbing these exact solutions, more general classes of models that satisfy the constant-roll equation asymptotically. In the case of an asymptotic power law solution, these corrections naturally provide an end to the inflationary phase. Interestingly, while from a theoretical point of view (in particular in terms of the holographic interpretation) these models are intrinsically different from standard slow-roll inflation, they may have phenomenological predictions in good agreement with present cosmological data.

  5. Upscaling of polymer solar cell fabrication using full roll-to-roll processing

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Tromholt, Thomas; Jørgensen, Mikkel

    2010-01-01

    factors (excluding bus bars) of 50, 67 and 75% respectively. In addition modules with lengths of 6, 10, 20, 22.5 and 25 cm were explored. The devices were prepared by full roll-to-roll solution processing in a web width of 305 mm and roll lengths of up to 200 m. The devices were encapsulated...... with a barrier material in a full roll-to-roll process using standard adhesives giving the devices excellent stability during storage and operation. The total area of processed polymer solar cell was around 60 m2 per run. The solar cells were characterised using a roll-to-roll system comprising a solar simulator...... to the cost for electricity using existing technologies the levelized cost of electricity (LCOE) is expected to be significantly higher than the existing technologies due to the inferior operational lifetime. The presented devices are thus competitive for consumer electronics but ill-suited for on...

  6. Inclusive Teaching Circles: Mechanisms for Creating Welcoming Classrooms

    Science.gov (United States)

    Moore, Sharon; Wallace, Sherri L.; Schack, Gina; Thomas, M. Shelley; Lewis, Linda; Wilson, Linda; Miller, Shawnise; D'Antoni, Joan

    2010-01-01

    This essay examines the Inclusive Teaching Circle (ITC) as a mechanism for faculty development in creating instructional tools that embrace an inclusive pedagogy reflecting diversity, cultural competence and social justice. We describe one group's year-long participation in an ITC at a large, metropolitan research university in the south. Next, we…

  7. Scaling laws for mode lockings in circle maps

    International Nuclear Information System (INIS)

    Cvitanovic, P.; Shraiman, B.; Soederberg, B.

    1985-06-01

    The self-similar structure of mode lockings for circle maps is studied by means of the associated Farey trees. We investigate numerically several classes of scaling relations implicit in the Farey organization of mode lockings and discuss the extent to which they lead to universal scaling laws. (orig.)

  8. Penerapan Model Beyond Centers and Circle Tme SD Kelas Satu

    OpenAIRE

    FITRIA, EVY

    2014-01-01

    Penelitian bertujuan mengkaji pelaksanaan penerapan model pembelajaran Sentra Model pembelajaran sentra (Beyond Centers and Circle Time) dilaksanakan pada siswa kelas satu SD Islam Jayawinata Kota Tangerang 2013. Penelitian menggunakan metode kualitatitf dengan analisis model Miles and Huberman. Hasil penelitian mengungkapkan bahwa kegiatan SD kelas satu menggunakan model pembelajaran sentra atau BCCT pada tahun ajaran baru sehingga guru memiliki panduan ketika membuat rencana pembelajaran; p...

  9. Uncertainty budget for optical coordinate measurements of circle diameter

    DEFF Research Database (Denmark)

    Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2004-01-01

    An uncertainty analysis for circle diameter measurements using a coordinate measuring machine (CMM) equipped with an optical probe is presented in this paper. A mathematical model for data evaluation and uncertainty assessment was formulated in accordance with Guide to the Expression of Uncertain...

  10. Full circle? Renato Amato's literary antipodes 1 | Hill | Italian Studies ...

    African Journals Online (AJOL)

    Il titolo stesso dell'opera di Amato The Full Circle of the Travelling Cuckoo (1967) rivela il senso di dislocazione dello scrittore migrante ma, al contempo, ne indica la capacità di riconciliarsi con il proprio difficile passato e di adattarsi alla sua patria adottiva, la Nuova Zelanda. Amato (1928-1964) ha dato un contribuito ...

  11. The Quality Control Circle: Is It for Education?

    Science.gov (United States)

    Land, Arthur J.

    From its start in Japan after World War II, the Quality Control Circle (Q.C.) approach to management and organizational operation evolved into what it is today: people doing similar work meeting regularly to identify, objectively analyze, and develop solutions to problems. The Q.C. approach meets Maslow's theory of motivation by inviting…

  12. Revisiting Cyberbullying in Schools Using the Quality Circle Approach

    Science.gov (United States)

    Paul, Simone; Smith, Peter K.; Blumberg, Herbert H.

    2012-01-01

    An earlier study reported the use of Quality Circles (QC) in a UK school in the context of understanding and reducing bullying and cyberbullying. Here, we report further work in the same school setting. The QC approach allows explorative analysis of problems in school settings, whereby students embark on a problem-solving exercise over a period of…

  13. Is Russell's vicious circle principle false or meaningless?

    NARCIS (Netherlands)

    Fleischhacker, L.E.

    1979-01-01

    P. Vardy asserts the thesis that the vicious circle principle has the same structure as Russell's paradox. But structure is not the thing itself. It is the thing objectivated from the wiewpoint of a mathematician. So this structure can be expressed in a mathematical formalism, e. g. the Λ-calculus.

  14. Random walks of a quantum particle on a circle

    International Nuclear Information System (INIS)

    Fjeldsoe, N.; Midtdal, J.; Ravndal, F.

    1987-07-01

    When the quantum planar rotor is put on a lattice, its dynamics can be approximated by random walks on a circle. This allows for fast and accurate Monto Carlo simulations to determine the topological charge of different configurations of the system and thereby the Θ-dependency of the lowest energy levels

  15. Come together – research circles as learning arenas

    DEFF Research Database (Denmark)

    Skovhus, Randi Boelskifte

    A presentation of an example of training through research circles. A training project that include teachers in compulsory school and researchers from Aarhus University and VIA University College. The presentation is based on a practice development project. First a short presentation of the projec...

  16. Circle Maps and the Devil's Staircase in a Chemical Oscillator

    DEFF Research Database (Denmark)

    Brøns, Morten; Gross, P.; Bar-Eli, K.

    1996-01-01

    We explain numerical results on a periodically perturbed Oregonator by Markman and Bar-Eli (J. Phys. Chem. 98 12248 (1994)). If the dynamics of the system is governed by a family of diffeomorphisms of a circle with a Devil's staircase one will expect the observed behavior, i.e. (1) Only periodic...

  17. Evolution of microstructure, macrotexture and microtexture during hot rolling of Ti-6Al-4V

    International Nuclear Information System (INIS)

    Ari-Gur, P.; Semiatin, S.L.

    1998-01-01

    The evolution of microstructure, macrotexture and microtexture during subtransus hot working of Ti-6Al-4V with two different types of transformed β starting microstructures (lamellar colony, acicular martensitic α) was investigated. Globularization of the transformed microstructures required heavy rolling reductions or moderate reductions coupled with near transus post-rolling heat treatment. Despite the sluggish dynamic globularization kinetics, noticeable macrotexture changes were noted after low reductions, an effect ascribed to the rotations associated with kinking and bending of the lamellar acicular plates. Noticeable microtextures, noted in samples with an initial lamellar colony microstructure, persisted through hot rolling suggesting that dynamic globularization does not involve recrystallization. In contrast, hot rolled material with a starting acicular α microstructure exhibited weak microtextures and strong macrotextures. The absence of microtexture in these latter cases was explained on the basis of multiple transformation variants within each colony/prior β grain following the β-annealing-and-water-quenching process used to obtain the microstructure. (orig.)

  18. How to square the CTBT circle

    International Nuclear Information System (INIS)

    Balachandran, G.

    2001-01-01

    The US pressure on India to at least sign the Comprehensive Test Ban Treaty (CTBT), if not ratify it, continues, and is unlikely to diminish. Those in India who suggest an unconditional acceptance of the CTBT, base it on the argument that having demonstrated its nuclear capability and thereby ensured its national security, India can sign the CTBT without holding out for the gains that may accrue from the act of signing. Those who are opposed to India signing the treaty base their objections on their doubts about the existence/reliability of the Indian nuclear deterrent. The third group comprises those who believe that India's current nuclear deterrent capability is satisfactory and India should sign the CTBT subject to certain gains in return. What is needed is a consensus in the country on signing the CTBT and the time is now appropriate for laying the groundwork for a national consensus without sacrificing the national interests. This article analyses the issues involved in India's signing the CTBT. (author)

  19. Inflation with a constant rate of roll

    International Nuclear Information System (INIS)

    Motohashi, Hayato; Starobinsky, Alexei A.; Yokoyama, Jun'ichi

    2015-01-01

    We consider an inflationary scenario where the rate of inflaton roll defined by ·· φ/H φ-dot remains constant. The rate of roll is small for slow-roll inflation, while a generic rate of roll leads to the interesting case of 'constant-roll' inflation. We find a general exact solution for the inflaton potential required for such inflaton behaviour. In this model, due to non-slow evolution of background, the would-be decaying mode of linear scalar (curvature) perturbations may not be neglected. It can even grow for some values of the model parameter, while the other mode always remains constant. However, this always occurs for unstable solutions which are not attractors for the given potential. The most interesting particular cases of constant-roll inflation remaining viable with the most recent observational data are quadratic hilltop inflation (with cutoff) and natural inflation (with an additional negative cosmological constant). In these cases even-order slow-roll parameters approach non-negligible constants while the odd ones are asymptotically vanishing in the quasi-de Sitter regime

  20. Design and analysis of roll cage

    Science.gov (United States)

    Angadi, Gurusangappa; Chetan, S.

    2018-04-01

    Wildlife fire fighting vehicles are used to extinguish fires in forests, in this process vehicles face falling objects like rocks, tree branches and other objects. Also due to uneven conditions of the terrain like cliff edges, uneven surfaces etc. makes the vehicle to roll over and these can cause injuries to both the driver and the operator. Roll over of a vehicle is a common incident which makes fatal injuries to the operator and also stands next to the crash accidents. In order to reduce the injury level and continuous roll over of the vehicle it is necessary to equip suitable roll cage according to standards of vehicle. In this present work roll cage for pump operator in wildfire fighting vehicle is designed and analysis is carried out in computer simulated environment when seating position of operator seated outside of the cabin. According to NFPA 1906 standards wildlife fire apparatus, Design and Test procedures that are carried out in Hyperworks maintaining SAE J1194.1983 standards. G load case, roof crush analysis and pendulum impact analysis tests are carried out on roll cage to ensure the saftey of design. These load cases are considerd to satisfy the situation faced in forest terrain. In these test procedures roll cage is analysed for stresses and deformation in various load cases. After recording results these are compared with standards mentioned in SAE J1194.1983.

  1. Inflationary dynamics with a smooth slow-roll to constant-roll era transition

    Energy Technology Data Exchange (ETDEWEB)

    Odintsov, S.D. [ICREA, Passeig Luis Companys, 23, 08010 Barcelona (Spain); Oikonomou, V.K., E-mail: odintsov@ieec.uab.es, E-mail: v.k.oikonomou1979@gmail.com [Laboratory for Theoretical Cosmology, Tomsk State University of Control Systems and Radioelectronics (TUSUR), Lenin Avenue 40, 634050 Tomsk (Russian Federation)

    2017-04-01

    In this paper we investigate the implications of having a varying second slow-roll index on the canonical scalar field inflationary dynamics. We shall be interested in cases that the second slow-roll can take small values and correspondingly large values, for limiting cases of the function that quantifies the variation of the second slow-roll index. As we demonstrate, this can naturally introduce a smooth transition between slow-roll and constant-roll eras. We discuss the theoretical implications of the mechanism we introduce and we use various illustrative examples in order to better understand the new features that the varying second slow-roll index introduces. In the examples we will present, the second slow-roll index has exponential dependence on the scalar field, and in one of these cases, the slow-roll era corresponds to a type of α-attractor inflation. Finally, we briefly discuss how the combination of slow-roll and constant-roll may lead to non-Gaussianities in the primordial perturbations.

  2. Innovation and Organizational Communication in Corporate America: The Rhetorical Visions of Managers, Facilitators, and Employees on Quality Circles.

    Science.gov (United States)

    Eyo, Bassey A.

    1992-01-01

    Examines the dynamics of organizational communication following corporate implementation of quality circles. Describes the rhetorical visions of people at three organizational levels closely associated with quality circles: (1) managers; (2) facilitators who organize the quality circles; and (3) employees. (SR)

  3. Are Namibian "fairy circles" the consequence of self-organizing spatial vegetation patterning?

    Directory of Open Access Journals (Sweden)

    Michael D Cramer

    Full Text Available Causes of over-dispersed barren "fairy circles" that are often surrounded by ca. 0.5 m tall peripheral grasses in a matrix of shorter (ca. 0.2 m tall grasses in Namibian grasslands remain mysterious. It was hypothesized that the fairy circles are the consequence of self-organizing spatial vegetation patterning arising from resource competition and facilitation. We examined the edaphic properties of fairy circles and variation in fairy circle size, density and landscape occupancy (% land surface with edaphic properties and water availability at a local scale (<50 km and with climate and vegetation characteristics at a regional scale. Soil moisture in the barren fairy circles declines from the center towards the periphery and is inversely correlated with soil organic carbon, possibly indicating that the peripheral grass roots access soil moisture that persists into the dry season within fairy circles. Fairy circle landscape occupancy is negatively correlated with precipitation and soil [N], consistent with fairy circles being the product of resource-competition. Regional fairy circle presence/absence is highly predictable using an empirical model that includes narrow ranges of vegetation biomass, precipitation and temperature seasonality as predictor variables, indicating that fairy circles are likely a climate-dependent emergent phenomenon. This dependence of fairy circle occurrence on climate explains why fairy circles in some locations may appear and disappear over time. Fairy circles are only over-dispersed at high landscape occupancies, indicating that inter-circle competition may determine their spacing. We conclude that fairy circles are likely to be an emergent arid-grassland phenomenon that forms as a consequence of peripheral grass resource-competition and that the consequent barren circle may provide a resource-reservoir essential for the survival of the larger peripheral grasses and provides a habitat for fossicking fauna.

  4. Look! It's Rock'n'roll!

    DEFF Research Database (Denmark)

    Lindelof, Anja

    2007-01-01

    , and dates. Consult your library or click here for more information on citing sources. -------------------------------------------------------------------------------- Anja Mølle Lindelof. (2007). Look! it's rock'n'roll! how television participated in shaping the visual genre conventions of popular music...... to personal names, capitalization, and dates. Consult your library or click here for more information on citing sources. -------------------------------------------------------------------------------- Anja Mølle Lindelof. "Look! It's Rock'n'roll! How television participated in shaping the visual genre....... Pay special attention to personal names, capitalization, and dates. Consult your library or click here for more information on citing sources. -------------------------------------------------------------------------------- TY - JOUR T1 - Look! It's Rock'n'roll! How television participated in shaping...

  5. Replication of nanopits and nanopillars by roll-to-roll extrusion coating using a structured cooling roll

    DEFF Research Database (Denmark)

    Murthy, Swathi; Pranov, Henrik; Pedersen, Henrik Chresten

    2016-01-01

    This paper investigates a novel, very high throughput, roll-to-roll (R2R) process for nanostructuring of polymer foils, called R2R extrusion coating. It has the potential to accelerate the integration of nanostructured materials in consumer products for a variety of applications, including optical....../height of 100 nm. The best replication was achieved in polypropylene, by running at high roller line-speed of 60 m/min, and high cooling roller temperature of 70°C. Replication in other common polymers like polyethylene and polystyrene was not possible for the parameter range used for the investigation......., technical, and functional surfaces and devices. In roll-to-roll extrusion coating, a molten polymer film is extruded through a flat die forming a melt curtain, and then laminated onto a carrier foil. The lamination occurs as the melt curtain is pressed between a cooling roller and a counter roller...

  6. Multivariable control of a rolling spider drone

    Science.gov (United States)

    Lyu, Haifeng

    The research and application of Unmanned Aerial Vehicles (UAVs) has been a hot topic recently. A UAV is dened as an aircraft which is designed not to carry a human pilot or operated with remote electronic input by the flight controller. In this thesis, the design of a control system for a quadcopter named Rolling Spider Drone is conducted. The thesis work presents the design of two kinds of controllers that can control the Drone to keep it balanced and track different kinds of input trajectories. The nonlinear mathematical model for the Drone is derived by the Newton-Euler method. The rotational subsystem and translational system are derived to describe the attitude and position motion of Drone. Techniques from linear control theory are employed to linearize the highly coupled and nonlinear quadcopter plant around equilibrium points and apply the linear feedback controller to stabilize the system. The controller is a digital tracking system that deploys LQR for system stability design. Fixed gain and adaptive gain scheduled controllers are developed and compared with different LQR weights. Step references and reference trajectories involving signicant variation for the yaw angle in the xy-plane and three-dimensional spaces are tracked in the simulation. The physical implementation and an output feedback controller are considered for future work.

  7. A localization algorithm of adaptively determining the ROI of the reference circle in image

    Science.gov (United States)

    Xu, Zeen; Zhang, Jun; Zhang, Daimeng; Liu, Xiaomao; Tian, Jinwen

    2018-03-01

    Aiming at solving the problem of accurately positioning the detection probes underwater, this paper proposed a method based on computer vision which can effectively solve this problem. The theory of this method is that: First, because the shape information of the heat tube is similar to a circle in the image, we can find a circle which physical location is well known in the image, we set this circle as the reference circle. Second, we calculate the pixel offset between the reference circle and the probes in the picture, and adjust the steering gear through the offset. As a result, we can accurately measure the physical distance between the probes and the under test heat tubes, then we can know the precise location of the probes underwater. However, how to choose reference circle in image is a difficult problem. In this paper, we propose an algorithm that can adaptively confirm the area of reference circle. In this area, there will be only one circle, and the circle is the reference circle. The test results show that the accuracy of the algorithm of extracting the reference circle in the whole picture without using ROI (region of interest) of the reference circle is only 58.76% and the proposed algorithm is 95.88%. The experimental results indicate that the proposed algorithm can effectively improve the efficiency of the tubes detection.

  8. Guided Discovery of the Nine-Point Circle Theorem and Its Proof

    Science.gov (United States)

    Buchbinder, Orly

    2018-01-01

    The nine-point circle theorem is one of the most beautiful and surprising theorems in Euclidean geometry. It establishes an existence of a circle passing through nine points, all of which are related to a single triangle. This paper describes a set of instructional activities that can help students discover the nine-point circle theorem through…

  9. The Value of the Math Circle for Gifted Middle School Students

    Science.gov (United States)

    Burns, Barbara; Henry, Julie; McCarthy, Dianne; Tripp, Jennifer

    2017-01-01

    Math Circles are designed to allow students to explore mathematics using a problem-solving/inquiry approach. Many of the students attending our Math Circle are mathematically talented and curious. This study examines the perspectives of the students and their families in determining why students attend Math Circle, what they enjoy about Math…

  10. The Chicken and the Egg: Inviting Response and Talk through Socratic Circles

    Science.gov (United States)

    Styslinger, Mary E.; Pollock, Timothy

    2010-01-01

    This collaborative inquiry answers the following questions: 1) What is the nature of talk during Socratic Circles? 2) What is student response to talk? 3) How might knowing more about student response to talk and the nature of talk improve teaching during Socratic Circles? The article first describes the process of implementing Socratic Circles,…

  11. Circling motion and screen edges as an alternative input method for on-screen target manipulation.

    Science.gov (United States)

    Ka, Hyun W; Simpson, Richard C

    2017-04-01

    To investigate a new alternative interaction method, called circling interface, for manipulating on-screen objects. To specify a target, the user makes a circling motion around the target. To specify a desired pointing command with the circling interface, each edge of the screen is used. The user selects a command before circling the target. To evaluate the circling interface, we conducted an experiment with 16 participants, comparing the performance on pointing tasks with different combinations of selection method (circling interface, physical mouse and dwelling interface) and input device (normal computer mouse, head pointer and joystick mouse emulator). A circling interface is compatible with many types of pointing devices, not requiring physical activation of mouse buttons, and is more efficient than dwell-clicking. Across all common pointing operations, the circling interface had a tendency to produce faster performance with a head-mounted mouse emulator than with a joystick mouse. The performance accuracy of the circling interface outperformed the dwelling interface. It was demonstrated that the circling interface has the potential as another alternative pointing method for selecting and manipulating objects in a graphical user interface. Implications for Rehabilitation A circling interface will improve clinical practice by providing an alternative pointing method that does not require physically activating mouse buttons and is more efficient than dwell-clicking. The Circling interface can also work with AAC devices.

  12. Absent collateral function of the circle of Willis as risk factor for ischemic stroke

    NARCIS (Netherlands)

    Hoksbergen, A. W. J.; Legemate, D. A.; Csiba, L.; Csáti, G.; Síró, P.; Fülesdi, B.

    2003-01-01

    Background. Autopsy studies show a higher prevalence of circle of Willis anomalies in brains with signs of ischemic infarction. Our goal was to examine the collateral function of the circle of Willis in ischemic stroke patients and to assess in a case-control study if a collateral deficient circle

  13. Roll paper pilot. [mathematical model for predicting pilot rating of aircraft in roll task

    Science.gov (United States)

    Naylor, F. R.; Dillow, J. D.; Hannen, R. A.

    1973-01-01

    A mathematical model for predicting the pilot rating of an aircraft in a roll task is described. The model includes: (1) the lateral-directional aircraft equations of motion; (2) a stochastic gust model; (3) a pilot model with two free parameters; and (4) a pilot rating expression that is a function of rms roll angle and the pilot lead time constant. The pilot gain and lead time constant are selected to minimize the pilot rating expression. The pilot parameters are then adjusted to provide a 20% stability margin and the adjusted pilot parameters are used to compute a roll paper pilot rating of the aircraft/gust configuration. The roll paper pilot rating was computed for 25 aircraft/gust configurations. A range of actual ratings from 2 to 9 were encountered and the roll paper pilot ratings agree quite well with the actual ratings. In addition there is good correlation between predicted and measured rms roll angle.

  14. Plasmonic color metasurfaces fabricated by a high speed roll-to-roll method

    DEFF Research Database (Denmark)

    Murthy, Swathi; Pranov, Henrik; Feidenhans'l, Nikolaj Agentoft

    2017-01-01

    Lab-scale plasmonic color printing using nano-structured and subsequently metallized surfaces have been demonstrated to provide vivid colors. However, upscaling these structures for large area manufacturing is extremely challenging due to the requirement of nanometer precision of metal thickness....... In this study, we have investigated a plasmonic color meta-surface design that can be easily upscaled. We have demonstrated the feasibility of fabrication of these plasmonic color surfaces by a high-speed roll-to-roll method, comprising roll-to-roll extrusion coating at 10 m min-1 creating a polymer foil having...... 100 nm deep pits of varying sub-wavelength diameter and pitch length. Subsequently this polymer foil was metallized and coated also by high-speed roll-to-roll methods. The perceived colors have high tolerance towards the thickness of the metal layer, when this thickness exceeds the depths of the pits...

  15. Calculation of locomotive traction force in transient rolling contact

    Directory of Open Access Journals (Sweden)

    Voltr P.

    2017-06-01

    Full Text Available To represent thewheel-rail contact in numerical simulations of rail vehicles, simplified models (Fastsim, Pola´ch etc. are usually employed. These models are designed for steady rolling only, which is perfectly suitable in many cases. However, it is shown to be limiting for simulations at very low vehicle speeds, and therefore it does not actually allow simulation of vehicle running at arbitrarily variable speed. The simplified model of transient rolling, which involves calculation of the stress distribution in the discretised contact area, overcomes this disadvantage but might be unnecessarily complex for more simple simulations. In this paper, an approximative creep force computation method for transient rolling is presented. Its purpose is not to study the transient phenomena themselves but provide a simple and readily available way to prevent incorrect results of the numerical simulation when the vehicle speed approaches zero. The proper function of the proposed method is demonstrated by a simulation of start-up and interrupted sliding of a four-axle locomotive.

  16. Optimal weights for circle fitting with discrete granular data

    International Nuclear Information System (INIS)

    Chernov, N.; Kolganova, E.; Ososkov, G.

    1995-01-01

    The problem of the data approximation measured along a circle by modern detectors in high energy physics, as for example, RICH (Ring Imaging Cherenkov) is considered. Such detectors having the discrete cell structure register the energy dissipation produced by a passing elementary particle not in a single point, but in several adjacent cells where all this energy is distributed. The presence of background hits makes inapplicable circle fitting methods based on the least square fit due to their noise sensitivity. In this paper it's shown that the efficient way to overcome these problems of the curve fitting is the robust fitting technique based on a reweighted least square method with optimally chosen weights, obtained by the use of maximum likelihood estimates. Results of numerical experiments are given proving the high efficiency of the suggested method. 9 refs., 5 figs., 1 tab

  17. Handwriting: three-dimensional kinetic synergies in circle drawing movements.

    Science.gov (United States)

    Hooke, Alexander W; Karol, Sohit; Park, Jaebum; Kim, Yoon Hyuk; Shim, Jae Kun

    2012-07-01

    The purpose of this study was to investigate central nervous system (CNS) strategies for controlling multifinger forces during a circle-drawing task. Subjects drew 30 concentric, discontinuous clockwise and counter clockwise circles, at self and experimenter-set paces. The three-dimensional trajectory of the pen's center of mass and the three-dimensional forces and moments of force at each contact between the hand and the pen were recorded. Uncontrolled Manifold Analysis was used to quantify the synergies between pen-hand contact forces in radial, tangential and vertical directions. Results showed that synergies in the radial and tangential components were significantly stronger than in the vertical component. Synergies in the clockwise direction were significantly stronger than the counterclockwise direction in the radial and vertical components. Pace was found to be insignificant under any condition.

  18. Co-Constructing Knowledge through NGO-Driven Circle Work

    DEFF Research Database (Denmark)

    Agerbæk, Jonas

    This presentation revolves around the question of what degree of control, if any, the users participating in NGO-driven development programs may have over their own development. Based on a multi-sited ethnography of NGO organizing and communication that I conducted in the period of 2010 to 2015......, and with a special analytical focus on the facilitating role of frontline NGO workers in rural East Africa, this presentation discusses enabling and constraining aspects of using circle work to co-produce knowledge in international development. More particularly I am focusing an approach to circle work called......, then participatory approaches such as REFLECT can be used not only to drive changes locally but also bolster the global participatory agenda of defining development practices and politics from the bottom and up...

  19. Rolling of molybdenum and niobium tubes on cold-rolling mill with high stiff stand

    Energy Technology Data Exchange (ETDEWEB)

    Potapov, I N; Shejkh-Ali, A D; Filimonov, G V; Lunev, A G

    1984-03-01

    To develop the technique of tube production the process of rolling is studied and comparative evaluation of the structure formed is carried out. It is shown that billets of rods deformed by screw rolling have the improved plastic properties and are deformed on cold-rolling mill (CRM) with a high degree of reduction without defect formation. High stiff stand of the CRM permits to produce high-quality molybdenum tubes.

  20. Decision Support for the Rolling Stock Dispatcher

    DEFF Research Database (Denmark)

    Groth, Julie Jespersen

    Real-time recovery is receiving a fast growing interest in an increasingly competitive railway operation market. This thesis considers the area of rolling stock dispatching which is one of the typical real-time railway dispatching problems. All work of the thesis is based on the network...... and planning processes of the railway operator DSB S-tog a/s. In the thesis the problems existing in the railway planning process from the strategic to real-time level are briefly sketched. Network planning, line planning, timetabling, crew and rolling stock planning is outlined and relevant references...... are given. Specifically the thesis references the operation research studies based on the railway operation of DSB S-tog a/s. Subsequently the process of dispatching is outlined with a specific emphasis on rolling stock. The rolling stock recovery problem is the problem of assigning train units to train...

  1. Terras: NATO õppuste roll Euroopas kasvab

    Index Scriptorium Estoniae

    2013-01-01

    Kaitseväe juhataja kindralmajor Riho Terrase sõnul suureneb lähiaastatel NATO õppuste roll Euroopas, sest Afganistanis sõdides saadud kogemust on vaja säilitada ning kasutada seda kollektiivkaitse tugevdamiseks

  2. Content-aware photo collage using circle packing.

    Science.gov (United States)

    Yu, Zongqiao; Lu, Lin; Guo, Yanwen; Fan, Rongfei; Liu, Mingming; Wang, Wenping

    2014-02-01

    In this paper, we present a novel approach for automatically creating the photo collage that assembles the interest regions of a given group of images naturally. Previous methods on photo collage are generally built upon a well-defined optimization framework, which computes all the geometric parameters and layer indices for input photos on the given canvas by optimizing a unified objective function. The complex nonlinear form of optimization function limits their scalability and efficiency. From the geometric point of view, we recast the generation of collage as a region partition problem such that each image is displayed in its corresponding region partitioned from the canvas. The core of this is an efficient power-diagram-based circle packing algorithm that arranges a series of circles assigned to input photos compactly in the given canvas. To favor important photos, the circles are associated with image importances determined by an image ranking process. A heuristic search process is developed to ensure that salient information of each photo is displayed in the polygonal area resulting from circle packing. With our new formulation, each factor influencing the state of a photo is optimized in an independent stage, and computation of the optimal states for neighboring photos are completely decoupled. This improves the scalability of collage results and ensures their diversity. We also devise a saliency-based image fusion scheme to generate seamless compositive collage. Our approach can generate the collages on nonrectangular canvases and supports interactive collage that allows the user to refine collage results according to his/her personal preferences. We conduct extensive experiments and show the superiority of our algorithm by comparing against previous methods.

  3. Quantum mechanics on the circle and W1+∞

    International Nuclear Information System (INIS)

    Floreanini, R.; Percacci, R.; Sezgin, E.

    1991-08-01

    The algebra W 1+∞ , with central charge c = 0, can be identified with the algebra of quantum observables of a particle moving on a circle. Mathematically, it is the universal enveloping algebra of the Euclidean algebra in two dimensions. Similarly, the super-W ∞ algebra is found to be the universal enveloping algebra of the super-Euclidean algebra in two dimensions. (author). 14 refs

  4. High accurate time system of the Low Latitude Meridian Circle.

    Science.gov (United States)

    Yang, Jing; Wang, Feng; Li, Zhiming

    In order to obtain the high accurate time signal for the Low Latitude Meridian Circle (LLMC), a new GPS accurate time system is developed which include GPS, 1 MC frequency source and self-made clock system. The second signal of GPS is synchronously used in the clock system and information can be collected by a computer automatically. The difficulty of the cancellation of the time keeper can be overcomed by using this system.

  5. Normal Isocurvature Surfaces and Special Isocurvature Circles (SIC)

    Science.gov (United States)

    Manoussakis, Gerassimos; Delikaraoglou, Demitris

    2010-05-01

    An isocurvature surface of a gravity field is a surface on which the value of the plumblines' curvature is constant. Here we are going to study the isocurvature surfaces of the Earth's normal gravity field. The normal gravity field is a symmetric gravity field therefore the isocurvature surfaces are surfaces of revolution. But even in this case the necessary relations for their study are not simple at all. Therefore to study an isocurvature surface we make special assumptions to form a vector equation which will hold only for a small coordinate patch of the isocurvature surface. Yet from the definition of the isocurvature surface and the properties of the normal gravity field is possible to express very interesting global geometrical properties of these surfaces without mixing surface differential calculus. The gradient of the plumblines' curvature function is vertical to an isocurvature surface. If P is a point of an isocurvature surface and "Φ" is the angle of the gradient of the plumblines' curvature with the equatorial plane then this direction points to the direction along which the curvature of the plumbline decreases / increases the most, and therefore is related to the strength of the normal gravity field. We will show that this direction is constant along a line of curvature of the isocurvature surface and this line is an isocurvature circle. In addition we will show that at each isocurvature surface there is at least one isocurvature circle along which the direction of the maximum variation of the plumblines' curvature function is parallel to the equatorial plane of the ellipsoid of revolution. This circle is defined as a Special Isocurvature Circle (SIC). Finally we shall prove that all these SIC lye on a special surface of revolution, the so - called SIC surface. That is to say, a SIC is not an isolated curve in the three dimensional space.

  6. CS Circles: An In-Browser Python Course for Beginners

    OpenAIRE

    Pritchard, David; Vasiga, Troy

    2012-01-01

    Computer Science Circles is a free programming website for beginners that is designed to be fun, easy to use, and accessible to the broadest possible audience. We teach Python since it is simple yet powerful, and the course content is well-structured but written in plain language. The website has over one hundred exercises in thirty lesson pages, plus special features to help teachers support their students. It is available in both English and French. We discuss the philosophy behind the cour...

  7. BANQUET SPEECH Full Circle: Star Ferry to Stardust

    Science.gov (United States)

    Matthews, Clifford N.

    2008-10-01

    Good evening. I'd like to invite you to join me on a journey that could be entitled “Full Circle: Star Ferry to Stardust”. “Star Ferry” represents Hong Kong, my home town, and especially its university - Hong Kong University - as I knew it during the years of World War II. “Stardust” refers to our gathering here to report on our research on possible organic chemistry in space.

  8. Social Circles Detection from Ego Network and Profile Information

    Science.gov (United States)

    2014-12-19

    way of organizing contacts in personal networks . They are therefore currently implemented in the major social net- working systems, such as Facebook ...0704-0188 3. DATES COVERED (From - To) - UU UU UU UU Approved for public release; distribution is unlimited. Social Circles Detection from Ego Network ...structural network information but also the contents of social interactions, with the aim to detect copying communities. The views, opinions and/or findings

  9. Discovering Social Circles in Ego Networks (Author’s Manuscript)

    Science.gov (United States)

    2013-01-10

    refer to as social cir- cles. Practically all major social networks provide such functionality, for example, ‘circles’ on Google+, and ‘lists’ on Facebook ...Discovering Social Circles in Ego Networks Julian McAuley and Jure Leskovec Stanford jmcauley@cs.stanford.edu, jure@cs.stanford.edu January 11, 2013...Abstract People’s personal social networks are big and cluttered, and currently there is no good way to automatically organize them. Social networking

  10. Truncated Calogero-Sutherland models on a circle

    Science.gov (United States)

    Tummuru, Tarun R.; Jain, Sudhir R.; Khare, Avinash

    2017-12-01

    We investigate a quantum many-body system with particles moving in a circle and subject to two-body and three-body potentials. This class of models, in which the range of interaction r can be set to a certain number of neighbors, extrapolates from a system with interactions up to next-to-nearest neighbors and the celebrated Calogero-Sutherland model. The exact ground state energy and a part of the excitation spectrum have been obtained.

  11. Ghost circles in lattice Aubry-Mather theory

    Science.gov (United States)

    Mramor, Blaz; Rink, Bob

    Monotone lattice recurrence relations such as the Frenkel-Kontorova lattice, arise in Hamiltonian lattice mechanics, as models for ferromagnetism and as discretization of elliptic PDEs. Mathematically, they are a multi-dimensional counterpart of monotone twist maps. Such recurrence relations often admit a variational structure, so that the solutions x:Z→R are the stationary points of a formal action function W(x). Given any rotation vector ω∈R, classical Aubry-Mather theory establishes the existence of a large collection of solutions of ∇W(x)=0 of rotation vector ω. For irrational ω, this is the well-known Aubry-Mather set. It consists of global minimizers and it may have gaps. In this paper, we study the parabolic gradient flow {dx}/{dt}=-∇W(x) and we will prove that every Aubry-Mather set can be interpolated by a continuous gradient-flow invariant family, the so-called 'ghost circle'. The existence of these ghost circles is known in dimension d=1, for rational rotation vectors and Morse action functions. The main technical result of this paper is therefore a compactness theorem for lattice ghost circles, based on a parabolic Harnack inequality for the gradient flow. This implies the existence of lattice ghost circles of arbitrary rotation vectors and for arbitrary actions. As a consequence, we can give a simple proof of the fact that when an Aubry-Mather set has a gap, then this gap must be filled with minimizers, or contain a non-minimizing solution.

  12. Disk partition function and oscillatory rolling tachyons

    International Nuclear Information System (INIS)

    Jokela, Niko; Jaervinen, Matti; Keski-Vakkuri, Esko; Majumder, Jaydeep

    2008-01-01

    An exact cubic open string field theory rolling tachyon solution was recently found by Kiermaier et al and Schnabl. This oscillatory solution has been argued to be related by a field redefinition to the simple exponential rolling tachyon deformation of boundary conformal theory. In the latter approach, the disk partition function takes a simple form. Out of curiosity, we compute the disk partition function for an oscillatory tachyon profile, and find that the result is nevertheless almost the same

  13. Maintenance in Railway Rolling Stock Rescheduling for Passenger Railways

    NARCIS (Netherlands)

    J.C. Wagenaar (Joris); L.G. Kroon (Leo)

    2015-01-01

    textabstractThis paper addresses the Rolling Stock Rescheduling Problem (RSRP), while taking maintenance appointments into account. After a disruption, the rolling stock of passenger trains has to be rescheduled in order to maintain a feasible rolling stock circulation. A limited number of rolling

  14. Sphalerons of O(3) nonlinear sigma model on a circle

    International Nuclear Information System (INIS)

    Funakubo, Koichi; Otsuki, Shoichiro; Toyoda, Fumihiko.

    1989-09-01

    A series of saddle point solutions of O(3) nonlinear sigma model with symmetry breaking term in 1 + 1 dimensions are obtained by imposing boundary condition either periodic or partially antiperiodic (O(3) sphalerons on a circle). Under the periodic boundary condition, classical features of the O(3) sphalerons are similar to scalar sphalerons of φ 4 model on a circle by Manton and Samols. Under the partially antiperiodic boundary condition, the lowest of the O(3) sphalerons coincides in the limit of infinite spatial domain with the O(3) sphaleron by Mottola and Wipf. In particular, zero and negative modes of them are examined in detail. An estimate of transition rate over the lowest O(3) sphaleron at finite temperature is made, and some remarks on simulating the transition on a lattice are given. One to one correspondence between these O(3) sphalerons on a circle and a series of (possible) classical solutions of SU(2) gauge-Higgs model, to which the electroweak sphaleron S and new sphaleron S* belong, is discussed. (author)

  15. [Data supporting quality circle management of inpatient depression treatment].

    Science.gov (United States)

    Brand, S; Härter, M; Sitta, P; van Calker, D; Menke, R; Heindl, A; Herold, K; Kudling, R; Luckhaus, C; Rupprecht, U; Sanner, Dirk; Schmitz, D; Schramm, E; Berger, M; Gaebel, W; Schneider, F

    2005-07-01

    Several quality assurance initiatives in health care have been undertaken during the past years. The next step consists of systematically combining single initiatives in order to built up a strategic quality management. In a German multicenter study, the quality of inpatient depression treatment was measured in ten psychiatric hospitals. Half of the hospitals received comparative feedback on their individual results in comparison to the other hospitals (bench marking). Those bench markings were used by each hospital as a statistic basis for in-house quality work, to improve the quality of depression treatment. According to hospital differences concerning procedure and outcome, different goals were chosen. There were also differences with respect to structural characteristics, strategies, and outcome. The feedback from participants about data-based quality circles in general and the availability of bench-marking data was positive. The necessity of carefully choosing quality circle members and professional moderation became obvious. Data-based quality circles including bench-marking have proven to be useful for quality management in inpatient depression care.

  16. Walt Disney World`s utility efficiency awards and environmental circles of excellence

    Energy Technology Data Exchange (ETDEWEB)

    Allen, P.J.; Kivler, W.B.

    1996-05-01

    This paper describes an innovative approach to energy conservation that has been started at WALT DISNEY WORLD. The program that was established was designed to heighten the awareness of energy usage in our Management and Cast Members, establish a method for recognizing and rewarding positive energy conservation efforts and, most importantly, keeping the effort simple and fun. Two programs work together to meet this goal: Utility Efficiency Awards and the Environmental Circles of Excellence. The Utility Efficiency Awards are given to the top areas that have demonstrated a reduction in utility consumption relative to the same period in prior years. More importantly, a report is generated that shows a best-to-worst ranking. Relying on the idea that {open_quotes}nobody wants to be on the bottom of the list{close_quotes}, conservation is enhanced by focusing attention on improving efficiency. To encourage direct cast member involvement in our environmental program, the Environmental Circles of Excellence were created. These groups, made up of hourly and salaried cast members, discuss their location`s environmental commitments, set goals and implement programs. This paper describes these initiatives in detail and presents some initial results that have heightened the awareness of energy conservation at WALT DISNEY WORLD.

  17. The Effect of Rolling As-Cast and Homogenized U-10Mo Samples on the Microstructure Development and Recovery Curves

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Vineet V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Paxton, Dean M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Burkes, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-07-30

    Over the past several years Pacific Northwest National Laboratory (PNNL) has been actively involved in supporting the U.S. Department of Energy National Nuclear Security Administration Office of Material Management and Minimization (formerly Global Threat Reduction Initiative). The U.S. High- Power Research Reactor (USHPRR) project is developing alternatives to existing highly enriched uranium alloy fuel to reduce the proliferation threat. One option for a high-density metal fuel is uranium alloyed with 10 wt% molybdenum (U-10Mo). Forming the U-10Mo fuel plates/foils via rolling is an effective technique and is actively being pursued as part of the baseline manufacturing process. The processing of these fuel plates requires systematic investigation/understanding of the pre- and post-rolling microstructure, end-state mechanical properties, residual stresses, and defects, their effect on the mill during processing, and eventually, their in-reactor performance. In the work documented herein, studies were conducted to determine the effect of cold and hot rolling the as-cast and homogenized U-10Mo on its microstructure and hardness. The samples were homogenized at 900°C for 48 h, then later annealed for several durations and temperatures to investigate the effect on the material’s microstructure and hardness. The rolling of the as-cast plate, both hot and cold, was observed to form a molybdenum-rich and -lean banded structure. The cold rolling was ineffective, and in some cases exacerbated the as-cast defects. The grains elongated along the rolling direction and formed a pancake shape, while the carbides fractured perpendicularly to the rolling direction and left porosity between fractured particles of UC. The subsequent annealing of these samples at sub-eutectoid temperatures led to rapid precipitation of the ' lamellar phase, mainly in the molybdenum-lean regions. Annealing the samples above the eutectoid temperature did not refine the grain size or the banded

  18. Roll-to-roll printed silver nanowires for increased stability of flexible ITO-free organic solar cell modules

    DEFF Research Database (Denmark)

    Benatto, Gisele Alves dos Reis; Roth, Bérenger; Corazza, Michael

    2016-01-01

    We report the use of roll-to-roll printed silver nanowire networks as front electrodes for fully roll-to-roll processed flexible indium-tin-oxide (ITO) free OPV modules. We prepared devices with two types of back electrodes, a simple PEDOT:PSS back electrode and a PEDOT:PSS back electrode...

  19. 75 FR 42782 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    Science.gov (United States)

    2010-07-22

    ...)] Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia AGENCY: United... Brazil and Japan, and the suspended investigation on hot-rolled steel from Russia. SUMMARY: The... Japan, and the suspended investigation on hot-rolled steel from Russia would be likely to lead to...

  20. 75 FR 62566 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    Science.gov (United States)

    2010-10-12

    ...)] Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia AGENCY: United... antidumping duty investigation on hot-rolled steel from Russia. SUMMARY: The Commission hereby gives notice of... suspended investigation on hot-rolled steel from Russia would be likely to lead to continuation or...

  1. Experimental study of circle grid fractal pattern on turbulent intensity in pipe flow

    International Nuclear Information System (INIS)

    Manshoor, B; Zaman, I; Othman, M F; Khalid, Amir

    2013-01-01

    Fractal turbulence is deemed much more efficient than grid turbulence in terms of a turbulence generation. In this paper, the hotwire experimental results for the circle grids fractal pattern as a turbulent generator will be presented. The self-similar edge characteristic of the circle grid fractal pattern is thought to play a vital role in the enhancement of turbulent intensity. Three different beta ratios of perforated plates based on circle grids fractal pattern were used in the experimental work and each paired with standard circle grids with similar porosity. The objectives were to study the fractal scaling influence on the flow and also to explore the potential of the circle grids fractal pattern in enhancing the turbulent intensity. The results provided an excellent insight of the fractal generated turbulence and the fractal flow physics. Across the circle grids fractal pattern, the pressure drop was lower but the turbulent intensity was higher than those across the paired standard circle grids

  2. Rolled lawn as tool for industrial barren remediation

    Science.gov (United States)

    Gorbacheva, T. T.; Ivanova, L. A.; Kikuchi, R.; Gerardo, R.

    2009-04-01

    Fast development of the industrial and urban territories during last century has led to great disturbance of natural ecosystems in a lot of regions of the world. In the Far North the risk resulted from technogenic influence involves essentially more expressed negative consequences for the nature comparing to a regions of averages and southern latitudes due to higher sensitivity of northern ecosystems. Since thirtieth years of last century industrial complexes on extraction and processing of nonferrous metals ores are functioned on Kola peninsula territory. They are powerful sources of emissions of acidifying substances and heavy metals. Long term influence of these emissions resulted in deep degradation of terrestrial ecosystems up to industrial barren arising in immediate proximity to industrial centre Monchegorsk. The most radical way of disturbed territories rehabilitation is biological remediation. In 2006-2008 innovative methods of high-quality grass cover performance was developed in local enterprise «VIPON» in Apatity. Vermiculite trademark «VIPON» is characterized by not broken structure of minerals combined with week reactance, high mechanical durability, favorable рН equal 6.5-7.0, valuable absorptive and ion exchange properties. Final product of proposed technology was rolled lawn which successfully applied for remediation of disturbed sites in urban territories as such as industrial plots with low contamination. One of abstract authors namely L.Ivanova is one of technology implementators. During 2008 the field test was performed near the smelter complex (67°51'N, 32°48'E) to estimate suitability of proposed method for site remediation in more severe conditions such as in industrial barren. The method is based on cultivation of perennial grasses using hydroponics with thermally inflated vermiculite from local deposit (Kovdor) followed by rolled lawn placement on very contaminated sites near Monchegorsk. Great advantage of rolled lawn is short

  3. Analysis of flat rolling of superconducting silver/ceramic composites

    DEFF Research Database (Denmark)

    Bech, Jakob Ilsted; Nielsen, Morten Storgård; Eriksen, Morten

    2001-01-01

    The flat rolling process from wire to tape is presumably the most crucial link in the chain of mechanical processes leading from loose powder and silver tubes to the final superconducting Ag/BSCCO tape. In order to improve the critical current density of the superconducting filaments, one must...... process these to the highest possible density without at the same time introducing failures as large cracks and macroscopic shear bands. In order to analyse and optimise the process, the interaction between the involved materials and their very different mechanical properties must be taken into account...

  4. Characterizing the stretch-flangeability of hot rolled multiphase steels

    International Nuclear Information System (INIS)

    Pathak, N.; Butcher, C.; Worswick, M.; Gao, J.

    2013-01-01

    Hole expansion tests are commonly used to characterize the edge stretching limit of a material. Traditionally, a conical punch is used to expand a punched hole until a through-thickness crack appears. However, many automotive stretch flanging operations involve in-plane edge stretching that is best captured with a flat punch. In this paper, hole expansion tests were carried out on two different hot-rolled multiphase steels using both flat and conical punches. The fracture mechanisms for both punch types were investigated using scanning electron microscopy (SEM)

  5. Preorganization of Nanostructured Inks for Roll-to-Roll-Coated Polymer Solar Cells

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Senkovskyy, Volodymyr; Kiriy, Anton

    2010-01-01

    , a preorganized ink was obtained that was used to make polymer solar cell modules in a full roll-to-roll coating and printing process operating in ambient air. The polymer solar cells were thus prepared by a mixture of slot die and flat-bed screen printing. Various polymer solar cell modules were prepared ranging...

  6. Technology development for roll-to-roll production of organic photovoltaics

    NARCIS (Netherlands)

    Galagan, Y.O.; Vries, I.G. de; Langen, A.P.; Andriessen, H.A.J.M.; Verhees, W.J.H.; Veenstra, S.C.; Kroon, J.M.

    2011-01-01

    In order to reach the objective of low-cost, large area organic photovoltaic systems, we build up a knowledge base concerning the influence of process conditions on the performance of polymer solar cells. A large area solar cell module, with roll-to-roll coated PEDOT:PSS and photoactive layers

  7. Material-Process-Performance Relationships for Roll-to-Roll Coated PEM Electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Mauger, Scott; Neyerlin, K.C.; Stickel, Jonathan; Ulsh, Michael; More, Karren; Wood, David

    2017-04-26

    Roll-to-roll (R2R) coating is the most economical and highest throughput method for producing fuel cell electrodes. R2R coating encompasses many different methodologies to create uniform films on a moving web substrate. Here we explore two coating methods, gravure and slot die, to understand the impacts of each on film uniformity and performance.

  8. Roll-to-roll paper sensors (ROPAS); Wireless communicating sensors on paper in the logistic chain

    NARCIS (Netherlands)

    Rentrop, C.; Rubingh, J.E.J.M.; Lelieveld, R.; Sandberg, H.

    2014-01-01

    The ROPAS project (Roll-to-roll paper sensors) combines high end electronics and wireless sensors with low cost paper substrates and processing techniques that can be applied on a large scale. Paper is the next step in the printed electronics roadmap of utilising cheaper substrate materials as a

  9. A Coupled Model for Work Roll Thermal Contour with Subsectional Cooling in Aluminum Strip Cold Rolling

    Directory of Open Access Journals (Sweden)

    Shao Jian

    2014-10-01

    Full Text Available Little attention had been given to the evaluation of subsectional cooling control ability under complicated working conditions. In this paper, heat generation was calculated by using finite difference method. Strip hardening, work roll elastic deformation and elastic recovery of strip were taken into account. The mean coefficient of convective heat transfer on work roll surface was simulated by FLUENT. Calculation model had used the alternative finite difference scheme, which improved the model stability and computing speed. The simulation result shows that subsectional cooling control ability is different between different rolling passes. Positive and negative control abilities are roughly the same in the same pass. The increase of rolled length, working pressure of header and friction coefficient has positive effect on subsectional cooling control ability, and the rolling speed is on the contrary. On the beginning of the pass, when work roll surface has not reached the stable temperature, control ability of subsectional cooling is mainly affected by rolled length. The effect of mean coefficient of convective heat transfer and coefficient of friction is linear. When rolling speed is over 500 m/min, control ability of subsectional cooling becomes stable.

  10. Influences of rolling method on deformation force in cold roll-beating forming process

    Science.gov (United States)

    Su, Yongxiang; Cui, Fengkui; Liang, Xiaoming; Li, Yan

    2018-03-01

    In process, the research object, the gear rack was selected to study the influence law of rolling method on the deformation force. By the mean of the cold roll forming finite element simulation, the variation regularity of radial and tangential deformation was analysed under different rolling methods. The variation of deformation force of the complete forming racks and the single roll during the steady state under different rolling modes was analyzed. The results show: when upbeating and down beating, radial single point average force is similar, the tangential single point average force gap is bigger, the gap of tangential single point average force is relatively large. Add itionally, the tangential force at the time of direct beating is large, and the dire ction is opposite with down beating. With directly beating, deformation force loading fast and uninstall slow. Correspondingly, with down beating, deformat ion force loading slow and uninstall fast.

  11. Research on the rolling moment in the symmetrical and asymmetrical rolling process

    Science.gov (United States)

    Alexa, V.; Raţiu, S. A.; Kiss, I.; Cioată, C. G.

    2017-01-01

    Research distribution the rolling moments symmetrical and asymmetrical report presents great importance both in theory and to introduce clarifications to the calculation of rolling resistance line assemblies. Clarifying individuals of metallic material deformation between the rolls single cylinder diameters act of any difference of work and analysis of advance and delay phenomena. Torque drive value for each of the rolling cylinders was done by reducing the thickness of the laminate samples, an experimental facility located in the laboratory of plastic deformation of the Faculty of Engineering Hunedoara. The analysis of research results show that in terms of power consumption for deformation and safety equipment in operation is rational for mills which require such a difference between the work rolls to execute about one cylinder operated.

  12. Dimensional ranges and rolling efficiency in a tandem cold rolling mill

    Energy Technology Data Exchange (ETDEWEB)

    Larkiola, J.

    1997-12-31

    In this work, physical models and a neural network theory have been combined in order to predict the properties of a steel strip and to optimise the process parameters in cold rolling. The prediction of the deformation resistance of the material and the friction parameter is based on the physical model presented by Bland, Ford and Ellis and artificial neural network computing (ANN). The accuracy of these models has been tested and proved by using a large amount of the measured data. With the aid of these models it has been shown that (a) the small change to the relative reduction distribution can have a clear effect upon the rolling efficiency, (b) the dimensional ranges of the tandem cold roll mill can be determined and optimised and (c) the possibility to cold roll a new product of new width, strength or thickness can be determined and the parameters of the tandem cold rolling process can be optimised. (orig.) 43 refs.

  13. Fundamentals of Rolling Contact Fatigue

    NARCIS (Netherlands)

    Grabulov, A.

    2010-01-01

    In the mechanical industry there is a need for continuous development towards increasing performance of various types of machinery. Critical components in such machines are exposed to gradually harsher operating environments involving higher cyclic stresses and operating temperatures. Examples of

  14. Magnon inflation: slow roll with steep potentials

    Energy Technology Data Exchange (ETDEWEB)

    Adshead, Peter [Department of Physics, University of Illinois at Urbana-Champaign,Urbana, IL 61801 (United States); Blas, Diego [Theoretical Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); Burgess, C.P.; Hayman, Peter [Physics & Astronomy, McMaster University,Hamilton, ON, L8S 4M1 (Canada); Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada); Patil, Subodh P. [Department of Theoretical Physics, University of Geneva,24 Quai Ansermet, Geneva, CH-1211 (Switzerland)

    2016-11-04

    We find multi-scalar effective field theories (EFTs) that can achieve a slow inflationary roll despite having a scalar potential that does not satisfy G{sup ab}∂{sub a}V∂{sub b}V≪V{sup 2}/M{sub p}{sup 2} (where G{sub ab} is the target-space metric). They evade the usual slow-roll conditions on V because their kinetic energies are dominated by single-derivative terms rather than the usual two-derivative terms. Single derivatives dominate during slow roll and so do not require a breakdown of the usual derivative expansion that underpins calculational control in much of cosmology. The presence of such terms requires some sort of UV Lorentz-symmetry breaking during inflation (besides the usual cosmological breaking). Chromo-natural inflation provides one particular example of a UV theory that can generate the multi-field single-derivative terms we consider, and we argue that the EFT we find indeed captures the slow-roll conditions for its background evolution. We also show that our EFT can be understood as a multi-field generalization of the single-field Cuscuton models. The multi-field case introduces a new feature, however: the scalar kinetic terms define a target-space 2-form, F{sub ab}, whose antisymmetry gives new ways for slow roll to be achieved.

  15. Magnon Inflation: Slow Roll with Steep Potentials

    CERN Document Server

    Adshead, Peter; Burgess, C P; Hayman, Peter; Patil, Subodh P

    2016-01-01

    We find multi-scalar effective field theories (EFTs) that can achieve a slow inflationary roll despite having a scalar potential that does not satisfy the usual slow-roll condition (d V)^2 << V^2/Mp^2. They evade the usual slow-roll conditions on $V$ because their kinetic energies are dominated by single-derivative terms rather than the usual two-derivative terms. Single derivatives dominate during slow roll and so do not require a breakdown of the usual derivative expansion that underpins calculational control in much of cosmology. The presence of such terms requires some sort of UV Lorentz-symmetry breaking during inflation (besides the usual cosmological breaking). Chromo-natural inflation provides an example of a UV theory that can generate the multi-field single-derivative terms we consider, and we argue that the EFT we find indeed captures the slow-roll conditions for the background evolution for Chromo-natural inflation. We also show that our EFT can be understood as a multi-field generalization ...

  16. Stereoscopic Machine-Vision System Using Projected Circles

    Science.gov (United States)

    Mackey, Jeffrey R.

    2010-01-01

    A machine-vision system capable of detecting obstacles large enough to damage or trap a robotic vehicle is undergoing development. The system includes (1) a pattern generator that projects concentric circles of laser light forward onto the terrain, (2) a stereoscopic pair of cameras that are aimed forward to acquire images of the circles, (3) a frame grabber and digitizer for acquiring image data from the cameras, and (4) a single-board computer that processes the data. The system is being developed as a prototype of machine- vision systems to enable robotic vehicles ( rovers ) on remote planets to avoid craters, large rocks, and other terrain features that could capture or damage the vehicles. Potential terrestrial applications of systems like this one could include terrain mapping, collision avoidance, navigation of robotic vehicles, mining, and robotic rescue. This system is based partly on the same principles as those of a prior stereoscopic machine-vision system in which the cameras acquire images of a single stripe of laser light that is swept forward across the terrain. However, this system is designed to afford improvements over some of the undesirable features of the prior system, including the need for a pan-and-tilt mechanism to aim the laser to generate the swept stripe, ambiguities in interpretation of the single-stripe image, the time needed to sweep the stripe across the terrain and process the data from many images acquired during that time, and difficulty of calibration because of the narrowness of the stripe. In this system, the pattern generator does not contain any moving parts and need not be mounted on a pan-and-tilt mechanism: the pattern of concentric circles is projected steadily in the forward direction. The system calibrates itself by use of data acquired during projection of the concentric-circle pattern onto a known target representing flat ground. The calibration- target image data are stored in the computer memory for use as a

  17. Autonomous Supervision and Control of Parametric Roll Resonance

    DEFF Research Database (Denmark)

    Galeazzi, Roberto

    therefore two objectives. The first is to develop methods for detection of the inception of parametric roll resonance. The second is to develop control strategies to stabilize the motion after parametric roll has started. Stabilisation of parametric roll resonance points to two possible courses of action...... strategies are then combined to stabilise parametric roll resonance within few roll cycles. Limitations on the maximum stabilisable roll angle are analysed and linked to the ii slew rate saturation and hydrodynamic stall characteristics of the fin stabilisers. The study on maximum stabilisable roll angle...... leads to the requirements for early detection. Two novel detectors are proposed, which work within a shorttime prediction horizon, and issue early warnings of parametric roll inception within few roll cycles from its onset. The main idea behind these detection schemes is that of exploiting the link...

  18. Voice of the voiceless: The legacy of the Circle of Concerned African Women Theologians

    Directory of Open Access Journals (Sweden)

    Hazel O. Ayanga

    2016-07-01

    Full Text Available The Circle of Concerned African Women Theologians (the Circle formally came into existence in 1989 in Accra, Ghana. Under the charismatic leadership of Mercy Amba Oduyoye, the Circle sought to be the voice of African Christian women at the grass roots level. To this end research and publication was and still is one of the major pillars and activities of the Circle. The main objective of the Circle is �to write and publish theological literature written by African women from their own experience of religion and culture on this continent�. In this regard the Circle has been and continues to be the voice for and on behalf of the African woman in religion, culture and theology. However, 25 years down the line there is need for an evaluation of the legacy of the Circle. How has the Circle been a voice for the voiceless, a mentoring instrument for women venturing into the academia? This article seeks to do this evaluation by examining the activities of the Circle including research publication.Intradisciplinary and/or interdisciplinary implications: This article seeks to evaluate the achievements of the Circle of Concerned African Women Theologians in relation to the Circle�s stated objectives. The article picks up the notion of the Circle theologians as the voice of the voiceless women of Africa. The general approach of the article brings together discussions on social issues like gender, poverty and marginalisation as well as language. Theological and religious perspectives on these issues are understood from a Circle point of view.Keywords: women; voice; voicelessness; poverty; gender; The Circle; theology

  19. The Function of Love in Solzhenitsyn's The First Circle

    Directory of Open Access Journals (Sweden)

    John Schillinger

    1977-01-01

    Full Text Available Aleksander Solzhenitsyn, like Boris Pasternak before him, insists upon the primacy of life over any socio-political system. To lead truly meaningful lives, his characters must comprehend that they are responsible for their own actions; that they are engaged in an existential struggle which pits individual freedom against the will of authority. In The First Circle , this struggle is clearly reflected in the theme of love which, when analyzed in terms of the suppression or triumph of its four basic elements ( sex, eros, philia, and agape , offers a convincing allegory of man's existential self-definition by free choice.

  20. Social Circles: A 3D User Interface for Facebook

    Science.gov (United States)

    Rodrigues, Diego; Oakley, Ian

    Online social network services are increasingly popular web applications which display large amounts of rich multimedia content: contacts, status updates, photos and event information. Arguing that this quantity of information overwhelms conventional user interfaces, this paper presents Social Circles, a rich interactive visualization designed to support real world users of social network services in everyday tasks such as keeping up with friends and organizing their network. It achieves this by using 3D UIs, fluid animations and a spatial metaphor to enable direct manipulation of a social network.

  1. Quality control circles: will they work at Sandia. Findings from a review of 66 sources

    Energy Technology Data Exchange (ETDEWEB)

    Jeys, G.H.

    1982-01-01

    Quality Control Circles (QCC's) meet regularly to solve limited, but important, problems related directly to their work. The QCC is organized so that the worker becomes involved in problem solving and quality awareness in meaningful and creative ways. Participation is voluntary. This concept has been successfully used in Japan for two decades. QCC's are now being implemented at an accelerating rate world-wide. There are questions as to QCC's applicability in the United States and in particular with respect to an R and D facility such as Sandia. This paper summarizes information about the QCC concept with respect to its implementation and applicability to Sandia. Information was extracted from 66 sources as noted in an Annotated Bibliography. Analysis techniques used by QCC's were utilized in the construction of this paper, especially with the Annotated Bibliography.

  2. A novel function for spumaretrovirus integrase: an early requirement for integrase-mediated cleavage of 2 LTR circles

    Directory of Open Access Journals (Sweden)

    Mouscadet Jean-François

    2005-05-01

    Full Text Available Abstract Retroviral integration is central to viral persistence and pathogenesis, cancer as well as host genome evolution. However, it is unclear why integration appears essential for retrovirus production, especially given the abundance and transcriptional potential of non-integrated viral genomes. The involvement of retroviral endonuclease, also called integrase (IN, in replication steps apart from integration has been proposed, but is usually considered to be accessory. We observe here that integration of a retrovirus from the spumavirus family depends mainly on the quantity of viral DNA produced. Moreover, we found that IN directly participates to linear DNA production from 2-LTR circles by specifically cleaving the conserved palindromic sequence found at LTR-LTR junctions. These results challenge the prevailing view that integrase essential function is to catalyze retroviral DNA integration. Integrase activity upstream of this step, by controlling linear DNA production, is sufficient to explain the absolute requirement for this enzyme. The novel role of IN over 2-LTR circle junctions accounts for the pleiotropic effects observed in cells infected with IN mutants. It may explain why 1 2-LTR circles accumulate in vivo in mutants carrying a defective IN while their linear and integrated DNA pools decrease; 2 why both LTRs are processed in a concerted manner. It also resolves the original puzzle concerning the integration of spumaretroviruses. More generally, it suggests to reassess 2-LTR circles as functional intermediates in the retrovirus cycle and to reconsider the idea that formation of the integrated provirus is an essential step of retrovirus production.

  3. f(R) constant-roll inflation

    Energy Technology Data Exchange (ETDEWEB)

    Motohashi, Hayato [Universidad de Valencia-CSIC, Instituto de Fisica Corpuscular (IFIC), Valencia (Spain); Starobinsky, Alexei A. [L.D. Landau Institute for Theoretical Physics, RAS, Moscow (Russian Federation); National Research University Higher School of Economics, Moscow (Russian Federation)

    2017-08-15

    The previously introduced class of two-parametric phenomenological inflationary models in general relativity in which the slow-roll assumption is replaced by the more general, constant-roll condition is generalized to the case of f(R) gravity. A simple constant-roll condition is defined in the original Jordan frame, and exact expressions for a scalaron potential in the Einstein frame, for a function f(R) (in the parametric form) and for inflationary dynamics are obtained. The region of the model parameters permitted by the latest observational constraints on the scalar spectral index and the tensor-to-scalar ratio of primordial metric perturbations generated during inflation is determined. (orig.)

  4. Influence of Surge on Extreme Roll Amplitudes

    DEFF Research Database (Denmark)

    Vidic-Perunovic, Jelena; Rognebakke, Olav; Pedersen, Preben Terndrup

    2008-01-01

    Interference of the wave-induced ship surge motion with roll dynamics has been studied. The surge motion has been included in a previously derived hydrodynamic roll prediction model in order to account for the ship speed variation due to the longitudinal incident wave pressure force. Depending...... balanced in order to determine the added thrust term that would represent actions to maintain speed The resulting forward speed variation affects the frequency of encounter and the parametric roll resonant condition is directly influenced by this speed variation. The analysis procedure is demonstrated...... for an example containership sailing mainly in head sea condition and higher sea states. Sensitivity of the results to the added thrust model and vertical motion calculation is discussed....

  5. Study of rolled uranium annealing process

    International Nuclear Information System (INIS)

    Cabane, G.

    1954-06-01

    The dilatometric study of rolled uranium clearly shows not only the expansions or contractions induced by stress relief or diffusion of vacancies, but also the slope variations of the cooling curves, which are the best evidence of a texture change. Under the microscope, hard-rolled sheets appear as a mixture of two distinct structures; it is also possible by intermediate annealing to prepare homogeneous sheets of either structure, i.e. twinned or untwinned. All these sheets which have similar textures, undergo at first a primary recrystallization beginning at 320 deg C, then a texture change without any apparent crystal growth, at about 430 deg C. (author) [fr

  6. Generalized slow roll for noncanonical kinetic terms

    International Nuclear Information System (INIS)

    Hu, Wayne

    2011-01-01

    We show that the generalized slow roll approach for calculating the power spectrum where the inflationary slow roll parameters are neither small nor slowly varying can be readily extended to models with noncanonical kinetic terms in the inflaton action. For example, rapid sound speed variations can arise in Dirac-Born-Infeld models with features in the warp factor leading to features in the power spectrum. Nonetheless there remains a single source function for deviations that is simply related to the power spectrum. Empirical constraints on this source function can be readily interpreted in the context of features in the inflaton potential or sound speed.

  7. Computer-aided roll pass design in rolling of airfoil shapes

    Science.gov (United States)

    Akgerman, N.; Lahoti, G. D.; Altan, T.

    1980-01-01

    This paper describes two computer-aided design (CAD) programs developed for modeling the shape rolling process for airfoil sections. The first program, SHPROL, uses a modular upper-bound method of analysis and predicts the lateral spread, elongation, and roll torque. The second program, ROLPAS, predicts the stresses, roll separating force, the roll torque and the details of metal flow by simulating the rolling process, using the slab method of analysis. ROLPAS is an interactive program; it offers graphic display capabilities and allows the user to interact with the computer via a keyboard, CRT, and a light pen. The accuracy of the computerized models was evaluated by (a) rolling a selected airfoil shape at room temperature from 1018 steel and isothermally at high temperature from Ti-6Al-4V, and (b) comparing the experimental results with computer predictions. The comparisons indicated that the CAD systems, described here, are useful for practical engineering purposes and can be utilized in roll pass design and analysis for airfoil and similar shapes.

  8. Inflation with a smooth constant-roll to constant-roll era transition

    Science.gov (United States)

    Odintsov, S. D.; Oikonomou, V. K.

    2017-07-01

    In this paper, we study canonical scalar field models, with a varying second slow-roll parameter, that allow transitions between constant-roll eras. In the models with two constant-roll eras, it is possible to avoid fine-tunings in the initial conditions of the scalar field. We mainly focus on the stability of the resulting solutions, and we also investigate if these solutions are attractors of the cosmological system. We shall calculate the resulting scalar potential and, by using a numerical approach, we examine the stability and attractor properties of the solutions. As we show, the first constant-roll era is dynamically unstable towards linear perturbations, and the cosmological system is driven by the attractor solution to the final constant-roll era. As we demonstrate, it is possible to have a nearly scale-invariant power spectrum of primordial curvature perturbations in some cases; however, this is strongly model dependent and depends on the rate of the final constant-roll era. Finally, we present, in brief, the essential features of a model that allows oscillations between constant-roll eras.

  9. "Pursuing a Lifetime of Healthful Physical Activity" through Falling and Rolling

    Science.gov (United States)

    Kozub, Francis M.; Hogan, John T.

    2013-01-01

    The basic movement concepts associated with falling and rolling are needed for many dynamic adult activities. This is the case any time the activity, either by intent or accident, involves safely transitioning from a standing position to the ground quickly. Failure to teach these skills in school physical education could result in a barrier to…

  10. R3D3 : The Rolling Receptionist Robot with Double Dutch Dialogue

    NARCIS (Netherlands)

    Linssen, Jeroen; Theune, Mariet

    We discuss the design of R3D3, a rolling receptionist robot with the ability to conduct 'double Dutch dialogues': dialogues (in Dutch) that involve, besides a human user, both a robot and a virtual human. R3D3 is intended to assist people when they visit shops, museums, or other establishments by

  11. R3D3: The Rolling Receptionist Robot with Double Dutch Dialogue

    NARCIS (Netherlands)

    Linssen, Jeroen; Theune, Mariet

    We discuss the design of R3D3, a rolling receptionist robot with the ability to conduct 'double Dutch dialogues': dialogues (in Dutch) that involve, besides a human user, both a robot and a virtual human. R3D3 is intended to assist people when they visit shops, museums, or other establishments by

  12. 78 FR 26110 - Kicking Cars and Going Between Rolling Equipment During Flat Switching Operations

    Science.gov (United States)

    2013-05-03

    ... Cars and Going Between Rolling Equipment During Flat Switching Operations AGENCY: Federal Railroad... occurred during a railroad switching operation that involved a railroad employee kicking cars and... make recommendations to railroads regarding the adoption of car-handling procedures during flat...

  13. Pre-big-bang cosmology and circles in the cosmic microwave background

    International Nuclear Information System (INIS)

    Nelson, William; Wilson-Ewing, Edward

    2011-01-01

    We examine the possibility that circles in the cosmic microwave background could be formed by the interaction of a gravitational wave pulse emitted in some pre-big-bang phase of the universe with the last scattering surface. We derive the expected size distribution of such circles, as well as their typical ring width and (for concentric circles) angular separation. We apply these results, in particular, to conformal cyclic cosmology, ekpyrotic cosmology as well as loop quantum cosmology with and without inflation in order to determine how the predicted geometric properties of these circles would vary from one model to the other, and thus, if detected, could allow us to differentiate between various pre-big-bang cosmological models. We also obtain a relation between the angular ring width and the angular radius of such circles that can be used in order to determine whether or not circles observed in the cosmic microwave background are due to energetic pre-big-bang events.

  14. Drawing Euler Diagrams with Circles: The Theory of Piercings.

    Science.gov (United States)

    Stapleton, Gem; Leishi Zhang; Howse, John; Rodgers, Peter

    2011-07-01

    Euler diagrams are effective tools for visualizing set intersections. They have a large number of application areas ranging from statistical data analysis to software engineering. However, the automated generation of Euler diagrams has never been easy: given an abstract description of a required Euler diagram, it is computationally expensive to generate the diagram. Moreover, the generated diagrams represent sets by polygons, sometimes with quite irregular shapes that make the diagrams less comprehensible. In this paper, we address these two issues by developing the theory of piercings, where we define single piercing curves and double piercing curves. We prove that if a diagram can be built inductively by successively adding piercing curves under certain constraints, then it can be drawn with circles, which are more esthetically pleasing than arbitrary polygons. The theory of piercings is developed at the abstract level. In addition, we present a Java implementation that, given an inductively pierced abstract description, generates an Euler diagram consisting only of circles within polynomial time.

  15. Foam Rolling for Delayed-Onset Muscle Soreness and Recovery of Dynamic Performance Measures

    Science.gov (United States)

    Pearcey, Gregory E. P.; Bradbury-Squires, David J.; Kawamoto, Jon-Erik; Drinkwater, Eric J.; Behm, David G.; Button, Duane C.

    2015-01-01

    Context: After an intense bout of exercise, foam rolling is thought to alleviate muscle fatigue and soreness (ie, delayed-onset muscle soreness [DOMS]) and improve muscular performance. Potentially, foam rolling may be an effective therapeutic modality to reduce DOMS while enhancing the recovery of muscular performance. Objective: To examine the effects of foam rolling as a recovery tool after an intense exercise protocol through assessment of pressure-pain threshold, sprint time, change-of-direction speed, power, and dynamic strength-endurance. Design: Controlled laboratory study. Setting: University laboratory. Patients or Other Participants: A total of 8 healthy, physically active males (age = 22.1 ± 2.5 years, height = 177.0 ± 7.5 cm, mass = 88.4 ± 11.4 kg) participated. Intervention(s): Participants performed 2 conditions, separated by 4 weeks, involving 10 sets of 10 repetitions of back squats at 60% of their 1-repetition maximum, followed by either no foam rolling or 20 minutes of foam rolling immediately, 24, and 48 hours postexercise. Main Outcome Measure(s): Pressure-pain threshold, sprint speed (30-m sprint time), power (broad-jump distance), change-of-direction speed (T-test), and dynamic strength-endurance. Results: Foam rolling substantially improved quadriceps muscle tenderness by a moderate to large amount in the days after fatigue (Cohen d range, 0.59 to 0.84). Substantial effects ranged from small to large in sprint time (Cohen d range, 0.68 to 0.77), power (Cohen d range, 0.48 to 0.87), and dynamic strength-endurance (Cohen d = 0.54). Conclusions: Foam rolling effectively reduced DOMS and associated decrements in most dynamic performance measures. PMID:25415413

  16. Calculation and experimental technique of determination of rolling procedure for cold-rolling tube mills

    International Nuclear Information System (INIS)

    Igoshin, V.F.; Aleshin, V.A.; Khoroshikh, Yu.G.; Bogatov, A.A.; Mizhiritskij, O.I.

    1983-01-01

    Calculation and experimental technique of determination of tube cold rolling procedure has been developed. Rolling procedure based on the usage of regression equation epsilon=1.24 psi, where psi is the relative reduction of area, delta-permissible reduction during rolling, has been tested on 08Kh18N10T steel. The effect of tube geometry, tool calibration parameters, lubrication conditions etc. on metal deformability in taking into account experimentally. The use of the technique proposed has allowed to shorten the time of mastering of the production of tubes from different steels

  17. Circle of willis and its variations; morphometric study in adult human cadavers

    OpenAIRE

    Raghavendra, Shirol VS, Daksha Dixit, Anil Kumar Reddy Y, Desai SP

    2014-01-01

    Background and Objectives: Circle of Willis plays a vital role in collateral circulation and redistribution of blood to all areas of the brain. Variation in circle of Willis is known to cause grave disorders like cerebrovascular disorders, subarachnoid haemorrhage, cerebral aneurysm and schizophrenia. The objectives of the present study are to study the formation and branching pattern of circle of Willis and also to study the distribution of variations. MATERIALS & Methods: The study was cond...

  18. Edges and vertices in a unique signed circle in a signed graph

    Directory of Open Access Journals (Sweden)

    Richard Behr

    2017-12-01

    Full Text Available We examine the conditions under which a signed graph contains an edge or a vertex that is contained in a unique negative circle or a unique positive circle. For an edge in a unique signed circle, the positive and negative case require the same structure on the underlying graph, but the requirements on the signature are different. We characterize the structure of the underlying graph necessary to support such an edge in terms of bridges of a circle. We then use the results from the edge version of the problem to help solve the vertex version.

  19. Measurement of Normal and Friction Forces in a Rolling Process

    DEFF Research Database (Denmark)

    Henningsen, Poul; Arentoft, Mogens; Wanheim, Tarras

    2004-01-01

    by the fric-tion conditions. To achieve this important informa-tion, measurements of the normal pressure and friction stresses in the deformation zone are re-quested. The direction of the friction stresses is changing during the rolling gap. At the entrance of the de-formation zone, the peripherical velocity...... of the roll is higher than for the incoming material, which causes frictional stresses at the material acting in the rolling direction. At the outlet of the rolling gap, the velocity of the deformed material exceeds the velocity of the roll, generating frictional stresses contrary to the direction of rolling....... In a narrow area in the deformation zone, the velocity of the de-formed material is equal to the velocity of the rolls. This area or line is named “neutral line”. The posi-tion of the neutral line depends on friction, reduc-tion ratio, diameter of the rolls, and width of the sheet....

  20. NON-CENTRAL ROLLING OF FLAT WORKS WITH TAPERED THICKNESS

    Directory of Open Access Journals (Sweden)

    I. A. Isaevich

    2010-01-01

    Full Text Available The way of forming of variable shape strips with rolling in non-drive waves with rounding by the movable arbor strip is analyzed. The way of rolling with derivation of speeds of deforming instruments is offered.

  1. Rolling Friction on a Wheeled Laboratory Cart

    Science.gov (United States)

    Mungan, Carl E.

    2012-01-01

    A simple model is developed that predicts the coefficient of rolling friction for an undriven laboratory cart on a track that is approximately independent of the mass loaded onto the cart and of the angle of inclination of the track. The model includes both deformation of the wheels/track and frictional torque at the axles/bearings. The concept of…

  2. 9 CFR 381.159 - Poultry rolls.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Poultry rolls. 381.159 Section 381.159... ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition § 381...

  3. The riddles of rock and roll

    NARCIS (Netherlands)

    L.J.M. d' Anjou (Leo)

    2003-01-01

    textabstractRock and roll has often been equated with rebellion. The genre, though, is just a form of popular music and many of the important players in the game of promoting it were, like the saying goes, only in it for the money. As a rule, music like that will be supportive of the social order

  4. Statistical prediction of parametric roll using FORM

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Choi, Ju-hyuck; Nielsen, Ulrik Dam

    2017-01-01

    Previous research has shown that the First Order Reliability Method (FORM) can be an efficient method for estimation of outcrossing rates and extreme value statistics for stationary stochastic processes. This is so also for bifurcation type of processes like parametric roll of ships. The present...

  5. Crowdsourcing rock n' roll multimedia retrieval

    NARCIS (Netherlands)

    Snoek, Cees G.M.; Freiburg, Bauke; Oomen, Johan; Ordelman, Roeland J.F.

    2010-01-01

    In this technical demonstration, we showcase a multimedia search engine that facilitates semantic access to archival rock n' roll concert video. The key novelty is the crowdsourcing mechanism, which relies on online users to improve, extend, and share, automatically detected results in video

  6. Detection of Parametric Roll on Ships

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Blanke, Mogens; Poulsen, Niels Kjølstad

    2012-01-01

    phenomenon could make the navigator change ship’s speed and heading, and these remedial actions could make the vessel escape the bifurcation. This chapter proposes non-parametric methods to detect the onset of parametric roll resonance. Theoretical conditions for parametric resonance are re...... on experimental data from towing tank tests and data from a container ship passing an Atlantic storm....

  7. Developing a medication communication framework across continuums of care using the Circle of Care Modeling approach

    Science.gov (United States)

    2013-01-01

    Background Medication errors are a common type of preventable errors in health care causing unnecessary patient harm, hospitalization, and even fatality. Improving communication between providers and between providers and patients is a key aspect of decreasing medication errors and improving patient safety. Medication management requires extensive collaboration and communication across roles and care settings, which can reduce (or contribute to) medication-related errors. Medication management involves key recurrent activities (determine need, prescribe, dispense, administer, and monitor/evaluate) with information communicated within and between each. Despite its importance, there is a lack of conceptual models that explore medication communication specifically across roles and settings. This research seeks to address that gap. Methods The Circle of Care Modeling (CCM) approach was used to build a model of medication communication activities across the circle of care. CCM positions the patient in the centre of his or her own healthcare system; providers and other roles are then modeled around the patient as a web of relationships. Recurrent medication communication activities were mapped to the medication management framework. The research occurred in three iterations, to test and revise the model: Iteration 1 consisted of a literature review and internal team discussion, Iteration 2 consisted of interviews, observation, and a discussion group at a Community Health Centre, and Iteration 3 consisted of interviews and a discussion group in the larger community. Results Each iteration provided further detail to the Circle of Care medication communication model. Specific medication communication activities were mapped along each communication pathway between roles and to the medication management framework. We could not map all medication communication activities to the medication management framework; we added Coordinate as a separate and distinct recurrent activity

  8. Developing a medication communication framework across continuums of care using the Circle of Care Modeling approach.

    Science.gov (United States)

    Kitson, Nicole A; Price, Morgan; Lau, Francis Y; Showler, Grey

    2013-10-17

    Medication errors are a common type of preventable errors in health care causing unnecessary patient harm, hospitalization, and even fatality. Improving communication between providers and between providers and patients is a key aspect of decreasing medication errors and improving patient safety. Medication management requires extensive collaboration and communication across roles and care settings, which can reduce (or contribute to) medication-related errors. Medication management involves key recurrent activities (determine need, prescribe, dispense, administer, and monitor/evaluate) with information communicated within and between each. Despite its importance, there is a lack of conceptual models that explore medication communication specifically across roles and settings. This research seeks to address that gap. The Circle of Care Modeling (CCM) approach was used to build a model of medication communication activities across the circle of care. CCM positions the patient in the centre of his or her own healthcare system; providers and other roles are then modeled around the patient as a web of relationships. Recurrent medication communication activities were mapped to the medication management framework. The research occurred in three iterations, to test and revise the model: Iteration 1 consisted of a literature review and internal team discussion, Iteration 2 consisted of interviews, observation, and a discussion group at a Community Health Centre, and Iteration 3 consisted of interviews and a discussion group in the larger community. Each iteration provided further detail to the Circle of Care medication communication model. Specific medication communication activities were mapped along each communication pathway between roles and to the medication management framework. We could not map all medication communication activities to the medication management framework; we added Coordinate as a separate and distinct recurrent activity. We saw many examples of

  9. Distinctive serum protein profiles involving abundant proteins in lung cancer patients based upon antibody microarray analysis

    Directory of Open Access Journals (Sweden)

    Rom William N

    2005-08-01

    Full Text Available Abstract Background Cancer serum protein profiling by mass spectrometry has uncovered mass profiles that are potentially diagnostic for several common types of cancer. However, direct mass spectrometric profiling has a limited dynamic range and difficulties in providing the identification of the distinctive proteins. We hypothesized that distinctive profiles may result from the differential expression of relatively abundant serum proteins associated with the host response. Methods Eighty-four antibodies, targeting a wide range of serum proteins, were spotted onto nitrocellulose-coated microscope slides. The abundances of the corresponding proteins were measured in 80 serum samples, from 24 newly diagnosed subjects with lung cancer, 24 healthy controls, and 32 subjects with chronic obstructive pulmonary disease (COPD. Two-color rolling-circle amplification was used to measure protein abundance. Results Seven of the 84 antibodies gave a significant difference (p Conclusion Our results suggest that a distinctive serum protein profile involving abundant proteins may be observed in lung cancer patients relative to healthy subjects or patients with chronic disease and may have utility as part of strategies for detecting lung cancer.

  10. Design of Experiment as a powerful tool when applying Finite Element Method: a case study on prediction of hot rolling process parameters

    Directory of Open Access Journals (Sweden)

    Giancarlo G. Bordonaro

    2018-04-01

    Full Text Available The ultimate goal in hot roll pass design is to manufacture a rolled product with the required dimensional accuracy, defect free surface, and mechanical properties. The proper selection of process parameters is crucial to meet increasing requirements for desired quality and geometrical properties of rolled products. Due to the complex behavior of the metal flow at high temperatures and the severe plastic deformations in shape rolling, most efforts that have been made so far only rely upon the practical experience gained by operators. The large number of variables involved and the difficulty in investigating the process characteristics, make the use of finite element (FE tools an effective and attractive opportunity towards a thorough understanding of the rolling process. In this work, Design of Experiment (DOE is proposed as a powerful and viable method for the prediction of rolling process parameters while reducing the computational effort. Nonlinear 3D FE models of the hot rolling process are developed for a large set of complex cross-section shapes and validated against experimental evidences provided by real plant products at each stage of the deformation sequence. Based on the accuracy of the validated FE models, DOE is applied to investigate the flat rolling process under a series of many parameters and scenarios. Effects of main roll forming variables are analyzed on material flow behavior and geometrical features of a rolled product. The selected DOE factors are the workpiece temperature, diameter size, diameter reduction (draught, and rolls angular velocity. The selected DOE responses are workpiece spread, effective stresses, contact stresses, and rolls reaction loads. Eventually, the application of Pareto optimality (a Multi-Criteria Decision Making method allows to detect an optimal combination of design factors which respect desired target requirements for the responses.

  11. Effect of Rolling Resistance in Dem Models With Spherical Bodies

    Directory of Open Access Journals (Sweden)

    Dubina Radek

    2016-12-01

    Full Text Available The rolling resistance is an artificial moment arising on the contact of two discrete elements which mimics resistance of two grains of complex shape in contact rolling relatively to each other. The paper investigates the influence of rolling resistance on behaviour of an assembly of spherical discrete elements. Besides the resistance to rolling, the contacts between spherical particles obey the Hertzian law in normal straining and Coulomb model of friction in shear.

  12. Roll-to-Roll fabrication of large area functional organic materials

    DEFF Research Database (Denmark)

    Søndergaard, Roar R.; Hösel, Markus; Krebs, Frederik C

    2013-01-01

    With the prospect of extremely fast manufacture of very low cost devices, organic electronics prepared by thin film processing techniques that are compatible with roll-to-roll (R2R) methods are presently receiving an increasing interest. Several technologies using organic thin films...... research fields such as organic photovoltaics, organic thin film transistors, light-emitting diodes, polymer electrolyte membrane fuel cells, and electrochromic devices. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 000: 000–000, 2012...

  13. Using Light-Induced Thermocleavage in a Roll-to-Roll Process for Polymer Solar Cells

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Norrman, Kion

    2010-01-01

    We report on the use of intense visible light with a narrow spectral distribution matched to the region where the conjugated polymer material absorbs to selectively heat the active material and induce thermocleavage. We show a full roll-to-roll process, leading to complete large-area polymer solar...... ion mass spectrometry, attenuated total reflectance infrared, and transmission/reflection UV−vis techniques....

  14. Roll-to-roll coated PBI membranes for high temperature PEM fuel cells

    DEFF Research Database (Denmark)

    Steenberg, Thomas; Hjuler, Hans Aage; Terkelsen, Carina

    2012-01-01

    We employed roll-to-roll coating in the preparation of 40 μm thick poly[2,2′(m-phenylene)-5,5′bibenzimidazole] (PBI) films for fuel cells using both knife-coating (KC) and slot-die (SD) coating. The films were coated directly from a 9% (w/w) solution of PBI in dimethylacetamide onto a sacrificial...

  15. Up-scaling perovskite solar cell manufacturing from sheet-to-sheet to roll-to-roll: challenges and solutions

    Science.gov (United States)

    Di Giacomo, Francesco; Galagan, Yulia; Shanmugam, Santhosh; Gorter, Harrie; van den Bruele, Fieke; Kirchner, Gerwin; de Vries, Ike; Fledderus, Henri; Lifka, Herbert; Veenstra, Sjoerd; Aernouts, Tom; Groen, Pim; Andrissen, Ronn

    2017-08-01

    Organometallic halide perovskite solar cells (PSCs) are extremely promising novel materials for thin-film photovoltaics, exhibiting efficiencies over 22% on glass and over 17% on foil 1, 2 . First, a sheet-to-sheet (S2S) production of PSCs and modules on 152x152 mm2 substrates was established, using a combination of sputtering, e-beam evaporation, slot die coating and thermal evaporation (average PCE of 14.6 +/- 1.3 % over 64 devices, more than 10% initial PCE on modules). Later the steps towards a roll-to-roll production will be investigated, starting from the optimization of the stack to make it compatible with a faster production at low temperature. A water based SnOx nanoparticles dispersion was used as solution processable ETL, and the deposition process was scaled-up from spin coating to R2R slot die coating on a 300 mm wide roll of PET/ITO. R2R production is often carried out in ambient atmosphere and involve the use of large volumes of materials, thus a first point is the development of a green solvent and precursor system for the perovskite layer to prevent the emission of toxic compound in the environment. The first results on device fabrication are encouraging, which allow partial R2R manufacturing of flexible PSC (R2R coating of SnOx and perovskite, S2S for Spiro-OMeTAD and gold) with stabilized PCE of 12.6%, a remarkable value for these novel devices. This result can be considered an important milestone towards the production of efficient, low cost, lightweight, flexible PSC on large area.

  16. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Milk bread, rolls, and buns. 136.130 Section 136.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns conforms...

  17. Lubrication in cold rolling : Numerical simulation using multigrid techniques

    NARCIS (Netherlands)

    Lugt, Pieter Martin

    1992-01-01

    In the cold rolling process a lubricant is applied on the rolls and/or the strip mate­rial. Due to the velocities of the rolls and the strip, part of the lubricant is sheared into the contact causing, amongst others, a reduction of the friction. In this thesis a physical-mathematical model is

  18. Metallurgical analysis of spalled work roll of hot strip mill

    International Nuclear Information System (INIS)

    Khan, M.M.; Khan, M.A.

    1993-01-01

    In this study failure analysis of four work roll of the Hot Strip Mill is carried out. The microstructure is correlated with the chemical composition of shell and roll-life. It was concluded that for the longer service of the roll, cementite, graphite and martensite should be balanced (as per working requirement of the mill). (author)

  19. Roll compaction and granulation system for nuclear fuel material

    International Nuclear Information System (INIS)

    Goldmann, L.H. Jr.; Holley, C.C.

    1981-01-01

    A roll compaction and roll granulation system has been designed and fabricated to replace conventional preslugging and crushing operations typically used in the fabrication of mixed oxide nuclear fuel pellets. This equipment will be of maintenance advantage with only the compaction and granulation rolls inside containment. The prototype is being tested and the results will be reported within a year

  20. Chaotic travelling rolls in Rayleigh–Bénard convection

    Indian Academy of Sciences (India)

    The lateral shift of the rolls may lead to a global flow reversal of the convective motion. The chaotic travelling rolls are observed in simulations with free-slip as well as no-slip boundary conditions on the velocity field. We show that the travelling rolls and the flow reversal are due to an interplay between the real and imaginary ...

  1. 14 CFR 27.493 - Braked roll conditions.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Braked roll conditions. 27.493 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Ground Loads § 27.493 Braked roll conditions. Under braked roll conditions with the shock absorbers in their static positions— (a) The limit...

  2. 14 CFR 23.493 - Braked roll conditions.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Braked roll conditions. 23.493 Section 23.493 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT....493 Braked roll conditions. Under braked roll conditions, with the shock absorbers and tires in their...

  3. 14 CFR 29.493 - Braked roll conditions.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Braked roll conditions. 29.493 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Ground Loads § 29.493 Braked roll conditions. Under braked roll conditions with the shock absorbers in their static positions— (a) The limit...

  4. Rolling Force Prediction in Heavy Plate Rolling Based on Uniform Differential Neural Network

    Directory of Open Access Journals (Sweden)

    Fei Zhang

    2016-01-01

    Full Text Available Accurate prediction of the rolling force is critical to assuring the quality of the final product in steel manufacturing. Exit thickness of plate for each pass is calculated from roll gap, mill spring, and predicted roll force. Ideal pass scheduling is dependent on a precise prediction of the roll force in each pass. This paper will introduce a concept that allows obtaining the material model parameters directly from the rolling process on an industrial scale by the uniform differential neural network. On the basis of the characteristics that the uniform distribution can fully characterize the solution space and enhance the diversity of the population, uniformity research on differential evolution operator is made to get improved crossover with uniform distribution. When its original function is transferred with a transfer function, the uniform differential evolution algorithms can quickly solve complex optimization problems. Neural network structure and weights threshold are optimized by uniform differential evolution algorithm, and a uniform differential neural network is formed to improve rolling force prediction accuracy in process control system.

  5. Roll-to-Roll Nanoforming of Metals Using Laser-Induced Superplasticity.

    Science.gov (United States)

    Goswami, Debkalpa; Munera, Juan C; Pal, Aniket; Sadri, Behnam; Scarpetti, Caio Lui P G; Martinez, Ramses V

    2018-05-24

    This Letter describes a low-cost, scalable nanomanufacturing process that enables the continuous forming of thin metallic layers with nanoscale accuracy using roll-to-roll, laser-induced superplasticity (R2RLIS). R2RLIS uses a laser shock to induce the ultrahigh-strain-rate deformation of metallic films at room temperature into low-cost polymeric nanomolds, independently of the original grain size of the metal. This simple and inexpensive nanoforming method does not require access to cleanrooms and associated facilities, and can be easily implemented on conventional CO 2 lasers, enabling laser systems commonly used for rapid prototyping or industrial cutting and engraving to fabricate uniform and three-dimensional crystalline metallic nanostructures over large areas. Tuning the laser power during the R2RLIS process enables the control of the aspect ratio and the mechanical and optical properties of the fabricated nanostructures. This roll-to-roll technique successfully fabricates mechanically strengthened gold plasmonic nanostructures with aspect ratios as high as 5 that exhibit high oxidation resistance and strong optical field enhancements. The CO 2 laser used in R2RLIS can also integrate the fabricated nanostructures on transparent flexible substrates with robust interfacial contact. The ability to fabricate ultrasmooth metallic nanostructures using roll-to-roll manufacturing enables the large scale production, at a relatively low-cost, of flexible plasmonic devices toward emerging applications.

  6. Circle Hough transform implementation for dots recognition in braille cells

    Science.gov (United States)

    Jacinto Gómez, Edwar; Montiel Ariza, Holman; Martínez Sarmiento, Fredy Hernán.

    2017-02-01

    This paper shows a technique based on CHT (Circle Hough Transform) to achieve the optical Braille recognition (OBR). Unlike other papers developed around the same topic, this one is made by using Hough Transform to process the recognition and transcription of Braille cells, proving CHT to be an appropriate technique to go over different non-systematics factors who can affect the process, as the paper type where the text to traduce is placed, some lightning factors, input image resolution and some flaws derived from the capture process, which is realized using a scanner. Tests are performed with a local database using text generated by visual nondisabled people and some transcripts by sightless people; all of this with the support of National Institute for Blind People (INCI for their Spanish acronym) placed in Colombia.

  7. Asymptotically stable phase synchronization revealed by autoregressive circle maps

    Science.gov (United States)

    Drepper, F. R.

    2000-11-01

    A specially designed of nonlinear time series analysis is introduced based on phases, which are defined as polar angles in spaces spanned by a finite number of delayed coordinates. A canonical choice of the polar axis and a related implicit estimation scheme for the potentially underlying autoregressive circle map (next phase map) guarantee the invertibility of reconstructed phase space trajectories to the original coordinates. The resulting Fourier approximated, invertibility enforcing phase space map allows us to detect conditional asymptotic stability of coupled phases. This comparatively general synchronization criterion unites two existing generalizations of the old concept and can successfully be applied, e.g., to phases obtained from electrocardiogram and airflow recordings characterizing cardiorespiratory interaction.

  8. Training of students’ special endurance in ping pong sport circles

    Directory of Open Access Journals (Sweden)

    V.M. Grinko

    2017-04-01

    Full Text Available Urpose: to test experimentally influence of aerobic trainings (cross country training and basic aerobic on students’ special endurance in sport oriented groups (sport circles, ping pong. Material: 106 first year students (n=53 - control group and n=53 - experimental participated in experiment. For determination of temporal series’ trends R-S analysis was used. Prognostication of mistakes’ quantity per one set was fulfilled with the help of exponential smoothing method. Results: it was shown that exponential smoothing method permits to prognosticate by one set ahead with rather high accuracy. As initial predictor we found mean quantity of mistakes in all sets. It permits to average all internal and external factors, which influence on the next predicting indicators. Such approach increases confidence of mistakes’ calculation in prognostication. Criteria of prognostication methodic for possible indicators’ values were also determined. Conclusions: the recommended time distribution in program is as follows: ping pong - 75%; cross country training and basic aerobic - 25%.

  9. G2 cubic transition between two circles with shape control

    Science.gov (United States)

    Habib, Zulfiqar; Sakai, Manabu

    2009-01-01

    This paper describes a method for joining two circles with an S-shaped or with a broken back C-shaped transition curve, composed of at most two spiral segments. In highway and railway route design or car-like robot path planning, it is often desirable to have such a transition. It is shown that a single cubic curve can be used for blending or for a transition curve preserving G2 continuity with local shape control parameter and more flexible constraints. Provision of the shape parameter and flexibility provide freedom to modify the shape in a stable manner which is an advantage over previous work by Meek, Walton, Sakai and Habib.

  10. Foucault dissipation in a rolling cylinder: a webcam quantitative study

    International Nuclear Information System (INIS)

    Bonanno, A; Bozzo, G; Camarca, M; Sapia, P

    2011-01-01

    In this paper we present an experimental strategy to measure the micro power dissipation due to Foucault 'eddy' currents in a copper cylinder rolling on two parallel conductive rails in the presence of a magnetic field. Foucault power dissipation is obtained from kinematical measurements carried out by using a common PC webcam and video analysis done by means of software tools freely available within Windows operating system (Paint and Movie Maker). The proposed method allows us to experimentally discern the contribution to dissipation due to the velocity-independent rolling friction from that owed to the viscous-like friction emerging from complex electrodynamic interactions among eddy currents and the external magnetic field. In this way a microdissipation of some tens of μW is measured. The easily reproducible experimental setup, the simple implementation of data analysis and the discussion on various experimental approaches and strategies make the proposed activity highly significant for university undergraduates, since involved crucial skills can be efficiently strengthened.

  11. Foucault dissipation in a rolling cylinder: a webcam quantitative study

    Energy Technology Data Exchange (ETDEWEB)

    Bonanno, A; Bozzo, G; Camarca, M; Sapia, P, E-mail: sapia@fis.unical.it [Physics Department, University of Calabria, I-87036 Rende, CS (Italy)

    2011-03-15

    In this paper we present an experimental strategy to measure the micro power dissipation due to Foucault 'eddy' currents in a copper cylinder rolling on two parallel conductive rails in the presence of a magnetic field. Foucault power dissipation is obtained from kinematical measurements carried out by using a common PC webcam and video analysis done by means of software tools freely available within Windows operating system (Paint and Movie Maker). The proposed method allows us to experimentally discern the contribution to dissipation due to the velocity-independent rolling friction from that owed to the viscous-like friction emerging from complex electrodynamic interactions among eddy currents and the external magnetic field. In this way a microdissipation of some tens of {mu}W is measured. The easily reproducible experimental setup, the simple implementation of data analysis and the discussion on various experimental approaches and strategies make the proposed activity highly significant for university undergraduates, since involved crucial skills can be efficiently strengthened.

  12. The Virtuous Circles of Clinical Information Systems: a Modern Utopia.

    Science.gov (United States)

    Degoulet, P

    2016-11-10

    Clinical information systems (CIS) are developed with the aim of improving both the efficiency and the quality of care. This position paper is based on the hypothesis that such vision is partly a utopian view of the emerging eSociety. Examples are drawn from 15 years of experience with the fully integrated Georges Pompidou University Hospital (HEGP) CIS and temporal data series extracted from the data warehouses of Assistance Publique - Hôpitaux de Paris (AP-HP) acute care hospitals which share the same administrative organization as HEGP. Three main virtuous circles are considered: user satisfaction vs. system use, system use vs. cost efficiency, and system use vs quality of care. In structural equation models (SEM), the positive bidirectional relationship between user satisfaction and use was only observed in the early HEGP CIS deployment phase (first four years) but disappeared in late post-adoption (≥8 years). From 2009 to 2013, financial efficiency of 20 AP-HP hospitals evaluated with stochastic frontier analysis (SFA) models diminished by 0.5% per year. The lower decrease of efficiency observed between the three hospitals equipped with a more mature CIS and the 17 other hospitals was of the same order of magnitude than the difference observed between pediatric and non-pediatric hospitals. Outcome quality benefits that would bring evidence to the system use vs. quality loop are unlikely to be obtained in a near future since they require integration with population-based outcome measures including mortality, morbidity, and quality of life that may not be easily available. Barriers to making the transformation of the utopian part of the CIS virtuous circles happen should be overcome to actually benefit the emerging eSociety.

  13. Differences in daily disposable circle lens performance characteristics

    Directory of Open Access Journals (Sweden)

    Schafer JM

    2014-04-01

    Full Text Available Jeffery M Schafer, William T Reindel, Marjorie J Rah, Osbert Chan, Lening Zhang Bausch & Lomb Incorporated, Rochester, NY, USA Purpose: The purpose of this evaluation was to compare the performance characteristics of two cosmetically tinted contact lenses in the circle lens category that differ in lens design, lens material, and pigment print pattern: etafilcon A (1-Day Acuvue Define; Johnson & Johnson Vision Care and hilafilcon B (Naturelle; Bausch & Lomb Incorporated. Methods: Two hundred Asian subjects (400 eyes were enrolled in this 1-month parallel, bilateral, randomized study at ten investigative sites. Study lenses were dispensed at a screening/dispensing visit, and follow-up visits occurred at 2 weeks and 1 month. Lenses were worn on a daily disposable basis. Fit characteristics were evaluated at each visit, and slit-lamp evaluations were completed at each follow-up visit. Results: Of the 200 patients enrolled, 172 (344 eyes completed the study. The proportion of eyes with fully centered lenses was statistically significantly higher for the hilafilcon B group at the 2-week and 1-month visits, P<0.05. Over all visits, 0.6% of hilafilcon B eyes demonstrated incomplete corneal coverage, whereas for the etafilcon A group, 8.5% of eyes demonstrated incomplete corneal coverage and/or edge lift. The proportion of eyes with adequate lens movement was statistically significantly higher for the hilafilcon B group, P<0.05. Over all visits, none of the hilafilcon B eyes was reported to have excessive movement, whereas for etafilcon A lenses, 10.2% of eyes were reported to have excessive movement. Conclusions: Etafilcon A lenses were significantly less likely to be fully centered and significantly more likely to have incomplete corneal coverage and/or edge lift compared with the hilafilcon B lenses. Keywords: cosmetic contact lens, circle contact lens

  14. Scalable, ambient atmosphere roll-to-roll manufacture of encapsulated large area, flexible organic tandem solar cell modules

    DEFF Research Database (Denmark)

    Andersen, Thomas Rieks; Dam, Henrik Friis; Hösel, Markus

    2014-01-01

    the manufacture of completely functional devices in exceptionally high yields. Critical to the ink and process development is a carefully chosen technology transfer to industry method where first a roll coater is employed enabling contactless stack build up, followed by a small roll-to-roll coater fitted to an X...

  15. Literature Circles in 18. Century; As a Cultural Centers of Istanbul: The Role of "Literature Circles" in the Transmission of The Cultural Heritage

    Directory of Open Access Journals (Sweden)

    Zehra ÖKSÜZ

    2015-08-01

    Full Text Available The aim of this study is to explore the particular examples of literature circles which were seen as wisdom centre and were influential in 18th century Ottoman social and cultural life. This study foc uses on the literature circles in the capital of Ottomans and examines their roles in the transmission of cultural heritage. Mahfil, which means the meeting place, became the centre of literature activities which are performed in a particular place. This li terature circles gained the status of being a prestigious literature and art centre which witnessed the creation of significant works in 18th. They functioned as a transmitter of culture in terms of the works studied and role model literary figures. Patron age tradition promoted the progress of literary activities in the circles. With regard to their significant contribution to the Ottoman culture and civilization, literature circles emerged at the patronage of Sultan III. Ahmed, Sultan III. Selim, Sadrazam Nevşehirli Damad İbrahim Paşa, Sadrazam Koca Râgıb Paşa, Hoca Neş’et Efendi, Şeyh Gâlib, Hoca Süleyman Vahyî. Therefore, it is essential to study these circles in terms of its importance as being home to important literary figures with a sophisticated sen se of art.

  16. LHC gets the ball rolling

    CERN Multimedia

    2007-01-01

    A technique involving a small ball with a transmitter embedded inside it has been successfully tested in Sector 7-8. The ball is sent through the LHC beam pipes to check the LHC interconnections. The multidisciplinary team responsible for the RF ball project to check the interconnections. From left to right: Rhodri Jones (AB/BI), Eva Calvo (AB/BI), Francesco Bertinelli (AT/MCS), Sonia Bartolome Jimenez (TS/IC), Sylvain Weisz (TS/IC), Paul Cruikshank (AT/VAC), Willemjan Maan (AT/VAC), Alain Poncet (AT/MCS), Marek Gasior (AB/BI). During the tests the ball is inserted very carefully into the vacuum chamber.A game of ping-pong at the LHC? On 13 September a rather unusual test was carried out in Sector 7-8 of the accelerator. A ball just a bit smaller than a ping-pong ball was carefully introduced into one of the accelerator’s two vacuum pipes, where it travelled 800 metres in the space of a few mi...

  17. On the minimal travel time needed to collect n items on a circle

    NARCIS (Netherlands)

    Litvak, Nelly; van Zwet, Willem R.

    2004-01-01

    Consider n items located randomly on a circle of length 1. The locations of the items are assumed to be independent and uniformly distributed on [0,1). A picker starts at point 0 and has to collect all n items by moving along the circle at unit speed in either direction. In this paper we study the

  18. On the minimal travel time needed to collect $n$ items on a circle

    NARCIS (Netherlands)

    Litvak, Nelli; van Zwet, Willem R.; van der Geer, Sarah; Wegkamp, Marten

    2012-01-01

    Consider $n$ items located randomly on a circle of length 1. The locations of the items are assumed to be independent and uniformly distributed on $[0,1)$. A picker starts at point 0 and has to collect all n items by moving along the circle at unit speed in either direction. In this paper we study

  19. On the minimal travel time needed to collect n items on a circle

    NARCIS (Netherlands)

    Litvak, Nelli; van Zwet, W.R.

    2002-01-01

    Consider n items located randomly on a circle of length 1. The locations of the items are assumed to be independent and uniformly distributed on [0, 1). A picker starts at point 0, and he has to collect all n items by moving along the circle at unit speed in either direction. In this paper we study

  20. Providing a Full Circle of Support to Teachers in an Inclusive Elementary School

    Science.gov (United States)

    Waldron, Nancy L.; Redd, Lacy

    2011-01-01

    Providing a full circle of support to teachers in an inclusive elementary school, the Newberry Elementary School (NES) principal and staff have worked for 5 years to ensure the inclusion of students with disabilities in general education classrooms. The authors would like to share their perceptions of how this full circle (the multiple systems) of…

  1. Quality Circles: How Effective Are They in Improving Employee Performance and Attitudes?

    Science.gov (United States)

    Buch, Kimberly; Raban, Amiram

    1990-01-01

    Used a quasi-experimental design to assess the effect of a quality circle intervention on behavior and attitudes of 88 employees at a large Midwestern organization. Results provide mixed support for the purported ability of circles to improve work behavior with no change for absenteeism and productivity but positive change for quality of work.…

  2. A surface containing a line and a circle through each point is a quadric

    KAUST Repository

    Nilov, Fedor K.; Skopenkov, Mikhail

    2012-01-01

    We prove that a surface in 3-dimensional Euclidean space containing a line and a circle through each point is a quadric. We also give some particular results on the classification of surfaces containing several circles through each point. © 2012 Springer Science+Business Media B.V.

  3. Exploring Writing Circles as Innovative, Collaborative Writing Structures with Teacher Candidates

    Science.gov (United States)

    Roberts, Sherron Killingsworth; Blanch, Norine; Gurjar, Nandita

    2017-01-01

    Writing circles are "small groups... meeting regularly to share drafts, choose common writing topics, practice positive response, and in general, help each other become better writers" (Vopat, 2009, p. 6). In this exploratory study, writing circles were employed with elementary teacher candidates in hopes of enhancing their perceptions…

  4. Comparing Interactions in Literature Circles in Both Online and in Class Discussions

    Science.gov (United States)

    Skeen, Christel Ghrist

    2014-01-01

    Discourse analysis of literature circles can lead educators to understand the different types of interactions taking place as students talk about text. Social and academic interactions exist in both face-to-face and online discussions of reading material. This study examines two different settings of literature circles and compares interactions of…

  5. 77 FR 55691 - Establishment of Class E Airspace; Circle Town, MT

    Science.gov (United States)

    2012-09-11

    ... (RNAV) Global Positioning System (GPS) standard instrument approach procedures at Circle Town County..., at Circle Town County Airport, to accommodate IFR aircraft executing new RNAV (GPS) standard..., Washington on August 30, 2012. Steven L. Vale, Acting Manager, Operations Support Group, Western Service...

  6. A surface containing a line and a circle through each point is a quadric

    KAUST Repository

    Nilov, Fedor K.

    2012-06-20

    We prove that a surface in 3-dimensional Euclidean space containing a line and a circle through each point is a quadric. We also give some particular results on the classification of surfaces containing several circles through each point. © 2012 Springer Science+Business Media B.V.

  7. Linearly Recurrent Circle Map Subshifts and an Application to Schrödinger Operators

    CERN Document Server

    Adamczewski, B

    2001-01-01

    We discuss circle map sequences and subshifts generated by them. We give a characterization of those sequences among them which are linearly recurrent. As an application we deduce zero-measure spectrum for a class of discrete one-dimensional Schrödinger operators with potentials generated by circle maps.

  8. Migraine without aura is not associated with incomplete circle of Willis

    DEFF Research Database (Denmark)

    Ezzatian-Ahar, Shabnam; Amin, Faisal Mohammad; Obaid, Hayder Ghani

    2014-01-01

    the prevalence of incomplete circle of Willis in migraineurs and controls. In the present study we compared the prevalence of incomplete circle of Willis in female migraine patients without aura to female healthy non-migraine controls.Using 3-Tesla magnetic resonance angiography we recorded three...

  9. Constant-roll tachyon inflation and observational constraints

    Science.gov (United States)

    Gao, Qing; Gong, Yungui; Fei, Qin

    2018-05-01

    For the constant-roll tachyon inflation, we derive the analytical expressions for the scalar and tensor power spectra, the scalar and tensor spectral tilts and the tensor to scalar ratio to the first order of epsilon1 by using the method of Bessel function approximation. The derived ns-r results are compared with the observations, we find that only the constant-roll inflation with ηH being a constant is consistent with the observations and observations constrain the constant-roll inflation to be slow-roll inflation. The tachyon potential is also reconstructed for the constant-roll inflation which is consistent with the observations.

  10. Fully Roll-to-Roll Gravure Printable Wireless (13.56 MHz) Sensor-Signage Tags for Smart Packaging

    Science.gov (United States)

    Kang, Hwiwon; Park, Hyejin; Park, Yongsu; Jung, Minhoon; Kim, Byung Chul; Wallace, Gordon; Cho, Gyoujin

    2014-06-01

    Integration of sensing capabilities with an interactive signage through wireless communication is enabling the development of smart packaging wherein wireless (13.56 MHz) power transmission is used to interlock the smart packaging with a wireless (13.56 MHz) reader or a smart phone. Assembly of the necessary componentry for smart packaging on plastic or paper foils is limited by the manufacturing costs involved with Si based technologies. Here, the issue of manufacturing cost for smart packaging has been obviated by materials that allow R2R (roll-to-roll) gravure in combination with R2R coating processes to be employed. R2R gravure was used to print the wireless power transmission device, called rectenna (antenna, diode and capacitor), and humidity sensor on poly(ethylene terephtalate) (PET) films while electrochromic signage units were fabricated by R2R coating. The signage units were laminated with the R2R gravure printed rectenna and sensor to complete the prototype smart packaging.

  11. Circles of Support and Accountability for Sex Offenders: A Systematic Review of Outcomes.

    Science.gov (United States)

    Clarke, Martin; Brown, Susan; Völlm, Birgit

    2017-08-01

    We conducted a systematic review of studies reporting on the effectiveness of Circles of Support and Accountability (Circles). Circles use volunteers to provide support for sex offenders living in the community. We searched 10 databases up to the end of 2013 and identified 3 relevant outcome studies. An additional 12 papers or reports were identified by searching reference lists, Google, and contacting key authors and Circles providers to obtain unpublished data. These 15 studies comprised one randomized controlled trial, three retrospective cohorts with matched controls, and 11 case series. The majority reported measures of recidivism, particularly reconviction. The 4 studies with controls generally reported that participation in Circles was associated with lower recidivism although there were few statistically significant differences. Few studies examined changes in risk or psychosocial outcomes. A number of methodological issues are discussed. Longer term, prospective follow-up studies with control groups are required to address these issues.

  12. Finite-element model to predict roll-separation force and defects during rolling of U-10Mo alloys

    Science.gov (United States)

    Soulami, Ayoub; Burkes, Douglas E.; Joshi, Vineet V.; Lavender, Curt A.; Paxton, Dean

    2017-10-01

    A major goal of the Convert Program of the U.S. Department of Energy's National Nuclear Security Administration (DOE/NNSA) is to enable high-performance research reactors to operate with low-enriched uranium rather than the high-enriched uranium currently used. To this end, uranium alloyed with 10 wt% molybdenum (U-10Mo) represents an ideal candidate because of its stable gamma phase, low neutron caption cross section, acceptable swelling response, and predictable irradiation behavior. However, because of the complexities of the fuel design and the need for rolled monolithic U-10Mo foils, new developments in processing and fabrication are necessary. This study used a finite-element code, LS-DYNA, as a predictive tool to optimize the rolling process. Simulations of the hot rolling of U-10Mo coupons encapsulated in low-carbon steel were conducted following two different schedules. Model predictions of the roll-separation force and roll pack thicknesses at different stages of the rolling process were compared with experimental measurements. The study reported here discussed various attributes of the rolled coupons revealed by the model (e.g., waviness and thickness non-uniformity like dog-boning). To investigate the influence of the cladding material on these rolling defects, other cases were simulated: hot rolling with alternative can materials, namely, 304 stainless steel and Zircaloy-2, and bare-rolling. Simulation results demonstrated that reducing the mismatch in strength between the coupon and can material improves the quality of the rolled sheet. Bare-rolling simulation results showed a defect-free rolled coupon. The finite-element model developed and presented in this study can be used to conduct parametric studies of several process parameters (e.g., rolling speed, roll diameter, can material, and reduction).

  13. 75 FR 64246 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Correction to Notice of...

    Science.gov (United States)

    2010-10-19

    ...-Rolled Carbon-Quality Steel Products From Brazil: Correction to Notice of Antidumping Duty Order AGENCY... certain hot-rolled flat-rolled carbon-quality steel products from Brazil. See Antidumping Duty Order: Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, 67 FR 11093 (March 12, 2002...

  14. Troll, a Language for specifying Dice-rolls

    DEFF Research Database (Denmark)

    Mogensen, Torben Ægidius

    2009-01-01

    Dice are used in many games, and often in fairly complex ways that make it difficult to unambiguously describe the dice-roll mechanism in plain language. Many role-playing games, such as Dungeons & Dragons, use a formalised notation for some instances of dice-rolls. This notation, once explained...... natural language to describe rolls. Even Dungeons & Dragons use formal notation only for some of the dice-roll methods used in the game. Hence, a more complete notation is in this paper proposed, and a tool for pseudo-random rolls and (nearly) exact probability calculations is described. The notation...... is called "Troll", combining the initial of the Danish word for dice ("terninger") with the English word "roll". It is a development of the language Roll described in an earlier paper. The present paper describes the most important features of Troll and its implementation....

  15. ROLLING PROCESS WITH OHSAS AND TEXTURE FORMATION– A REVIEW

    Directory of Open Access Journals (Sweden)

    P. CHANDRAMOHAN

    2009-03-01

    Full Text Available Rolling is a mechanical treatment, which plays an important part in the processing of ferrous and nonferrous alloys. Texturing is an important phenomenon that occurs after rolling process. Preferred orientation increases the strength of the material enormously. Hence the research is focused on the rolling studies and the texture formation, which occurs after rolling process. This review mainly focuses on rolling process carried out in different alloys. It also highlights the analysis made on various rolling parameters for improving the mechanical properties. Texture studies carried on various ferrous and non-ferrous alloys; particularly in nitrogen alloyed duplex stainless steel is discussed. Finally the need for implementation of occupational health and safety during a thermomechanical treatment is also discussed. The state of art in this field is encouraging and showing positive signs of commercializing rolled nitrogen alloyed duplex stainless steel after proper texture control.

  16. DESIGN OF PARTICULATE MATERIAL COMPACTOR ROLLS DIAMETER

    Directory of Open Access Journals (Sweden)

    Peter Peciar

    2017-09-01

    Full Text Available At present, in a period of an industrial expansion great emphasis is placed on the environment. That means aiming for a reduced energy consumption, and also lessening dustiness from very fine powder material. This category also includes particulate material agglomeration processes. Because this process is very energy-intensive, it is necessary to correctly design these devices. The aim of this paper is to focus on a theoretical design of a production compactor with the rolls diameter for an experimental particulate material, based on Johanson’s theory and experimentally measured material properties. The material used for experimental measurements was an NPK-based industrial fertilizer consisting of several components. The results of this paper is the dependence of the ratio of the maximum compression pressure to the initial compression pressure from the rolls diameter of the proposed compactor.

  17. Contact conditions in skin-pass rolling

    DEFF Research Database (Denmark)

    Kijima, Hideo; Bay, Niels

    2007-01-01

    The special contact conditions in skin-pass rolling of steel strip is analysed by studying plane strain upsetting of thin sheet with low reduction applying long narrow tools and dry friction conditions. An extended sticking region is estimated by an elasto-plastic FEM analysis of the plane strain...... upsetting. This sticking region causes a highly inhomogeneous elasto-plastic deformation with large influence of work-hardening and friction. A numerical analysis of skin-pass rolling shows the same contact conditions, i.e. an extended sticking region around the center of the contact zone. The calculated...... size of the sticking region with varying contact length and pressure/reduction is experimentally verified by plane strain upsetting tests measuring the local surface deformation of the work pieces after unloading....

  18. A NOVEL ROLLING BASED DNA CRYPTOGRAPHY

    Directory of Open Access Journals (Sweden)

    Rejwana Haque

    2017-05-01

    Full Text Available DNA Cryptography can be defined as a hiding data in terms of DNA Sequence. In this paper we propose a new DNA Encryption Technique where three different types of ordering is use to make binary data into cipher text. The main stages of this encryption technique are: Key Analysis, Data and Key Arrangement, Roll in encoding, Secondary Arrangement and Shifting. Decryption process has six main steps to obtain the original binary data from the encrypted data and key. Decryption steps are: Key Analysis, Shifting, Secondary Arrangement, Key Arrangement, Roll-out decoding, Data Arrangement. Here key size is half of binary data and the key is varies from data to data so key are used as one time pad. In this paper we also discuss about the implementation from sample data and security analysis for this given method.

  19. Slipping and rolling on an inclined plane

    International Nuclear Information System (INIS)

    Aghamohammadi, Cina; Aghamohammadi, Amir

    2011-01-01

    In the first part of the paper, using a direct calculation two-dimensional motion of a particle sliding on an inclined plane is investigated for general values of friction coefficient (μ). A parametric equation for the trajectory of the particle is also obtained. In the second part of the paper, the motion of a sphere on the inclined plane is studied. It is shown that the evolution equation for the contact point of a sliding sphere is similar to that of a point particle sliding on an inclined plane whose friction coefficient is 7/2 μ. If μ > 2/7 tan θ, for any arbitrary initial velocity and angular velocity, the sphere will roll on the inclined plane after some finite time. In other cases, it will slip on the inclined plane. In the case of rolling, the centre of the sphere moves on a parabola. Finally the velocity and angular velocity of the sphere are exactly computed.

  20. Properties of hot rolled steels for enamelling

    International Nuclear Information System (INIS)

    Gavrilovski, Dragica; Gavrilovski, Milorad

    2003-01-01

    The results of an investigation of the structure and properties of experimental produced hot rolled steels suitable for enamelling are presented in the paper. Hot rolled steels for enamelling represent a special group of the steels for conventional enamelling. Their quality has to be adapted to the method and conditions of enamelling. Therefore, these steels should meet some specific requirements. In addition to usual investigation of the chemical composition and mechanical properties, microstructure and quality of the steel surface also were investigated. The basic aim was to examine steels capability for enamelling, i. e. steels resistance to the fish scales phenomena, by trial enamelling, as well as quality of the steel - enamel contact surface, to evaluate the binding. Also, the changes of the mechanical properties, especially the yield point, during thermal treatment, as a very specific requirement, were investigated, by simplified method. Good results were obtained confirming the steels capability for enamelling. (Original)

  1. Dynamics and Stability of Rolling Viscoelastic Tires

    Energy Technology Data Exchange (ETDEWEB)

    Potter, Trevor [Univ. of California, Berkeley, CA (United States)

    2013-04-30

    Current steady state rolling tire calculations often do not include treads because treads destroy the rotational symmetry of the tire. We describe two methodologies to compute time periodic solutions of a two-dimensional viscoelastic tire with treads: solving a minimization problem and solving a system of equations. We also expand on work by Oden and Lin on free spinning rolling elastic tires in which they disovered a hierachy of N-peak steady state standing wave solutions. In addition to discovering a two-dimensional hierarchy of standing wave solutions that includes their N-peak hiearchy, we consider the eects of viscoelasticity on the standing wave solutions. Finally, a commonplace model of viscoelasticity used in our numerical experiments led to non-physical elastic energy growth for large tire speeds. We show that a viscoelastic model of Govindjee and Reese remedies the problem.

  2. Heritability of circle of Willis variations in families with intracranial aneurysms.

    Directory of Open Access Journals (Sweden)

    Mayte Sánchez van Kammen

    Full Text Available Intracranial aneurysms more often occur in the same arterial territory within families. Several aneurysm locations are associated with specific circle of Willis variations. We investigated whether the same circle of Willis variations are more likely to occur in first-degree relatives than in unrelated individuals.We assessed four circle of Willis variations (classical, A1-asymmetry, incomplete posterior communicating artery and fetal circulation in two independent groups of families with familial aneurysms and ≥2 first-degree relatives with circle of Willis imaging on MRA/CTA. In each (index family we determined the proportion of first-degree relatives with the same circle of Willis variation as the proband and compared it to the proportion of first-degree relatives of a randomly selected unrelated (comparison family who had the same circle of Willis variation as the index family's proband. Concordance in index families and comparison families was compared with a conditional logistic events/trials model. The analysis was simulated 1001 times; we report the median concordances, odds ratios (ORs, and 95% confidence intervals (95%CI. The groups were analysed separately and together by meta-analysis.We found a higher overall concordance in circle of Willis configuration in index families than in comparison families (meta-analysis, 244 families: OR 2.2, 95%CI 1.6-3.0 mostly attributable to a higher concordance in incomplete posterior communicating artery (meta-analysis: OR 2.8, 95%CI 1.8-4.3. No association was found for the other three circle of Willis variations.In two independent groups of families with familial aneurysms, the incomplete PcomA variation occurred more often within than between families suggesting heritability of this circle of Willis variation. Further studies should investigate genetic variants associated with circle of Willis formation.

  3. A Model of Active Roll Vehicle Suspension

    Directory of Open Access Journals (Sweden)

    I. Čech

    2010-01-01

    Full Text Available This paper describes active suspension with active roll for four-wheel vehicle (bus by means of an in-series pump actuator with doubled hydropneumatic springs. It also gives full control law with no sky-craping. Lateral stiffness and solid axle geometry in the mechanical model are not neglected. Responses to lateral input as well as responses to statistical unevennesses show considerable improvement of passengers comfort and safety when cornering.

  4. Extreme chirality in Swiss roll metamaterials

    International Nuclear Information System (INIS)

    Demetriadou, A; Pendry, J B

    2009-01-01

    The chiral Swiss roll metamaterial is a resonant, magnetic medium that exhibits a negative refractive band for one-wave polarization. Its unique structure facilitates huge chiral effects: a plane polarized wave propagating through this system can change its polarization by 90 deg. in less than a wavelength. Such chirality is at least 100 times greater than previous structures have achieved. In this paper, we discuss this extreme chiral behaviour with both numerical and analytical results.

  5. Contact fatigue in rolling-element bearings

    CSIR Research Space (South Africa)

    Fernandes, PJL

    1997-06-01

    Full Text Available to the "cyclone pitting effect" also observed in gear teeth \\[1\\]. The initiation of surface cracks under rollin~sliding contact can be significantly accelerated by the presence of stress concentration sites on the contact surf... formed by rolling and rollin~sliding contact fatigue may progress to form a more severe form of damage known as flaking \\[3\\]. This results in the formation of large, irregular pits which cause rapid deterioration...

  6. Rapid roll inflation with conformal coupling

    International Nuclear Information System (INIS)

    Kofman, Lev; Mukohyama, Shinji

    2008-01-01

    Usual inflation is realized with a slow rolling scalar field minimally coupled to gravity. In contrast, we consider dynamics of a scalar with a flat effective potential, conformally coupled to gravity. Surprisingly, it contains an attractor inflationary solution with the rapidly rolling inflaton field. We discuss models with the conformal inflaton with a flat potential (including hybrid inflation). There is no generation of cosmological fluctuations from the conformally coupled inflaton. We consider realizations of modulated (inhomogeneous reheating) or curvaton cosmological fluctuations in these models. We also implement these unusual features for the popular string-theoretic warped inflationary scenario, based on the interacting D3-D3 branes. The original warped brane inflation suffers a large inflaton mass due to conformal coupling to 4-dimensional gravity. Instead of considering this as a problem and trying to cure it with extra engineering, we show that warped inflation with the conformally coupled, rapidly rolling inflaton is yet possible with N=37 efoldings, which requires low-energy scales 1-100 TeV of inflation. Coincidentally, the same warping numerology can be responsible for the hierarchy. It is shown that the scalars associated with angular isometries of the warped geometry of compact manifold (e.g. S 3 of Klebanov-Strassler (KS) geometry) have solutions identical to conformally coupled modes and also cannot be responsible for cosmological fluctuations. We discuss other possibilities

  7. Rapid roll inflation with conformal coupling

    Science.gov (United States)

    Kofman, Lev; Mukohyama, Shinji

    2008-02-01

    Usual inflation is realized with a slow rolling scalar field minimally coupled to gravity. In contrast, we consider dynamics of a scalar with a flat effective potential, conformally coupled to gravity. Surprisingly, it contains an attractor inflationary solution with the rapidly rolling inflaton field. We discuss models with the conformal inflaton with a flat potential (including hybrid inflation). There is no generation of cosmological fluctuations from the conformally coupled inflaton. We consider realizations of modulated (inhomogeneous reheating) or curvaton cosmological fluctuations in these models. We also implement these unusual features for the popular string-theoretic warped inflationary scenario, based on the interacting D3-D¯3 branes. The original warped brane inflation suffers a large inflaton mass due to conformal coupling to 4-dimensional gravity. Instead of considering this as a problem and trying to cure it with extra engineering, we show that warped inflation with the conformally coupled, rapidly rolling inflaton is yet possible with N=37 efoldings, which requires low-energy scales 1 100 TeV of inflation. Coincidentally, the same warping numerology can be responsible for the hierarchy. It is shown that the scalars associated with angular isometries of the warped geometry of compact manifold (e.g. S3 of Klebanov-Strassler (KS) geometry) have solutions identical to conformally coupled modes and also cannot be responsible for cosmological fluctuations. We discuss other possibilities.

  8. Swiss roll operation for giant fibroadenoma.

    Science.gov (United States)

    Soomro, Saleem A; Memon, Sohail A; Mohammad, Noor; Maher, Mumtaz

    2009-01-01

    Fibroadenoma 5 cm or more is called giant fibroadenoma. Giant fibroadenoma can distort the shape of breast and causes asymmetry, so it should be excised. There are several techniques for excision of giant fibroadenoma. In our technique we remove them through cosmetically acceptable circumareolar incision to maintain the shape and symmetry of breast. The objectives were to assess the cosmetic results of Swiss roll operation for giant fibroadenoma. The study was conducted for six years from January, 2002 to December, 2007. Seventy patients of giant fibroadenoma were included in this study. They were diagnosed on history and clinical examination supported by ultrasound and postoperative histopathological examination. Data were collected from outpatient department and operation theatre. Swiss roll operation was performed under general anaesthesia. Mean tumor size was 6.38 cm. Three cm and 4 cm incisions were used for tumour 6 cm in size respectively. Skin closed with Vicryl 3/0 subcuticular stitches. Sixteen out of 70 patients had no scar while others hadminimal scar. All patients had normal shape and symmetry of breast. On histopathology fibroadenoma was confirmed. Giant fibroadenoma should be removed through cosmetically acceptable cicumareolar incision especially in unmarried young females who have small breast. Swiss-roll operation is superior in maintaining the shape and symmetry of breast. No major complication was found in our series except seroma formation in 10 patients.

  9. Bi-Hamiltonian systems on the dual of the Lie algebra of vector fields of the circle and periodic shallow water equations

    OpenAIRE

    Kolev, Boris

    2006-01-01

    23 pages; International audience; This paper is a survey article on bi-Hamiltonian systems on the dual of the Lie algebra of vector fields on the circle. We investigate the special case where one of the structures is the canonical Lie-Poisson structure and the second one is constant. These structures called affine or modified Lie-Poisson structures are involved in the integrability of certain Euler equations that arise as models of shallow water waves.

  10. The role of Circle women in curbing violence against women and girls in Africa

    Directory of Open Access Journals (Sweden)

    Sylvia Owusu-Ansah

    2016-07-01

    Full Text Available The article looks at the role Circle of Concerned African Women Theologians (the Circle have played in the struggle to end or reduce the rate at which violence against women and girls occurs in West Africa by highlighting the contributions of older Circle women, especially the initiator of the Circle, Mercy Amba Oduyoye. The initiator of the Circle and other older Circle women have left a remarkable legacy that needs to continue by the current and future generations of the Circle. The background information examines the leadership and mentorship of Mercy Amba Oduyoye and the impact she has made in the lives of African women. The essay then looks at the types of violence that women face in West Africa with the specific contributions of Circle women in the struggle to end violence against women and girls. It then argues that Circle women have played very significant roles both in setting the pace and giving the platform for women activities to minimise gender-based violence against women and girls. Circle women have written and presented papers that have addressed many challenges including HIV and/or AIDS, Girl Child trafficking, Marriage of Minors, and almost all kinds of violence against women and girls. Currently, religious violence threatens the fabric of African nations causing insecurity and panic, women and girls being the most vulnerable. The challenge to the present and future Circle members is to contribute in significant ways towards religious harmony in Africa and beyond. The Circle acknowledges the leadership role of women and encourages them to spearhead the liberation of women as well as empower them to be able to aspire to get to the top or become independent. No one understands what someone else feels better than the person experiencing the ordeal. Women can better understand what they go through and also have the passion to strive towards liberation.Intradisciplinary and/or interdisciplinary implications: In this article, the

  11. Rolls-Royce digital Rod Control System

    International Nuclear Information System (INIS)

    Pouillot, M.

    2010-01-01

    Full text of publication follows: Rolls-Royce has developed a new generation of Rod Control System, based on 40 years of experience. The fifth-generation Rod Control System (RCS) from Rolls-Royce offers a reliable, modular design with adaptability to your preferred platform, for modernization projects or new reactors. Flexible implementation provides the option for you to keep existing cabinets, which permits you to optimize installation approach. Main features for the power part: - Control Rod Drive Mechanism (CRDM) type: 3-coil. - Independent control of each sub-bank. - Each sub-bank is controlled by a cycler unit and 3 identical power racks, each including 4 identical power modules and a common power-supply module. - Coil-per-coil digital control: each power module embeds power-conversion, current-control, and current-monitoring functions for one coil. Control and monitoring are carried out by separate electronics in the module. Current is digitized and fully monitored by means of min-max templates. - A double-hold function is included: a power module assigned to a gripper will activate its coil if a fault risking to cause a reactor trip occurs. - Power modules are standardized, hot-pluggable and self-configured: a power module includes a set of parameters for each type of coil SG, MG, LC. The module recognizes the rack it is plugged in, and chooses automatically parameters to be used. Main benefits: - Reduced operational, maintenance, training, and inventory costs: standardization of power modules and integration of control and monitoring on the same PC-card lead to a drastic reduction of spare part types, and simplification of the system. - Easy maintenance: - Replacement of a power module solves nearly all failures due to current control or monitoring for a coil. It is done instantly thanks to hot-plug capability. - On the front plate of power-modules, LEDs provide useful information for diagnostic: current setpoint from cycler, output current bar

  12. Voltage and Thermally Driven Roll-to-Roll Organic Printed Transistor Made in Ambient Air Conditions

    DEFF Research Database (Denmark)

    Pastorelli, Francesco

    of the organic semiconductor poly3hexylthiophene and the dielectric material polyvinylphenol before the gate was applied by screen printing. All the processing was realized in ambient air on a PET flexible substrate. We explore the footprint and the practically accessible geometry of such devices with a special......Resume: Organic thin film transistors offer great potential for use in flexible electronics. Much of this potential lies in the solution processability of the organic polymers enabling both roll coating and printing on flexible substrates and thus greatly reducing the material and fabrication costs....... We present flexible organic power transistors prepared by fast (20 m min−1) roll-to-roll flexographic printing of the drain and source electrode structures, with an interspace below 50 um, directly on polyester foil[1]. The devices have top gate architecture and were completed by slotdie coating...

  13. A new transducer for local load measurements of friction and roll pressure in cold flat rolling

    DEFF Research Database (Denmark)

    Lagergren, J.; Wanheim, Tarras; Precz, W.

    2006-01-01

    The only way to establish the true rolling pressure and the true friction condition in cold rolling is to conduct measurements in the roll bite. A new transducer design is therefore proposed, in order to overcome problems in previous measurements in the past 70 years. The new idea is to increase ...... and able to avoid signal disturbance. The pressure and friction stress distribution results was as expected by the authors and showed good reproducibility, together with a proven agreement between recorded and simulated signals....... selected from a steady state with no disturbance from the material flow. The transducer was able to simultaneously measure both the normal pressure and the friction stress. An estimation of the coefficient of friction was accordingly performed. The new transducer works very well, it was seen to be robust...

  14. ANALYSIS OF ENERGY SAVING AND ENERGY EFFICIENCY ISSUES DURING OPERATION OF THE METRO ROLLING STOCK

    Directory of Open Access Journals (Sweden)

    A. V. Donchenko

    2016-06-01

    Full Text Available Purpose.Nowadays a problem of significant power consumption of the rolling stock during its operation is a current issue. In connection with staged electricity rates increase further development of the rail electric transport, including metro rolling stock is impossible without a use of modern energy saving solutions and energy-efficient systems. To solve the specified problem it is necessary to carry out analysis of measures and determine prospective directions in energy saving and increase of energy efficiency on the metro rolling stock. Methodology. Using methods of scientific analysis, generalization, comparative analysis, forecasting and using results of experimental studies, the authors determined main ways for reduction of energy consumption during operation of the metro rolling stock. Energy cost analysis for metro rolling stock of the public utility (PU «Kiev Metro» was carried out. A great number of research works of native and foreign authors concerning the above mentioned problem were analyzed. Findings. Principal directions in energy saving and increase of energy efficiency of the metro rolling stock are implementation of recuperation systems, energy storage systems and energy-efficient control systems. It was determined that implementation of recuperation and energy storage systems helps to save a considerable amount of energy, consumed for traction, but it involves substantial investments. It is pointed out that in current complicated conditions of economic development of Ukraine, use of energy-efficient control systems is a perspective direction in energy saving. Main advantage of this direction is the economic effect obtaining without significant investments. Originality. For the first time was performed potential assessment for energy saving as a result of energy-efficient control systems use at type routine rolling stock operation modes on sections «Khreschatik –Teatralnaya – Khreschatik» and «Shulyavskaya

  15. The Wigner semi-circle law in quantum electro dynamics

    International Nuclear Information System (INIS)

    Accardi, L.; Nagoya Univ.; Lu, Y.G.; Nagoya Univ.

    1996-01-01

    In the present paper, the basic ideas of the stochastic limit of quantum theory are applied to quantum electro-dynamics. This naturally leads to the study of a new type of quantum stochastic calculus on a Hilbert module. Our main result is that in the weak coupling limit of a system composed of a free particle (electron, atom,..) interacting, via the minimal coupling, with the quantum electromagnetic field, a new type of quantum noise arises, living on a Hilbert module rather than a Hilbert space. Moreover we prove that the vacuum distribution of the limiting field operator is not Gaussian, as usual, but a nonlinear deformation of the Wigner semi-circle law. A third new object arising from the present theory, is the so-called interacting Fock space. A kind of Fock space in which the n quanta, in the n-particle space, are not independent, but interact. The origin of all these new features is that we do not introduce the dipole approximation, but we keep the exponential response term, coupling the electron to the quantum electromagnetic field. This produces a nonlinear interaction among all the modes of the limit master field (quantum noise) whose explicit expression, that we find, can be considered as a nonlinear generalization of the Fermi golden rule. (orig.)

  16. End of the line to build a circle

    CERN Multimedia

    2006-01-01

    The installation of the cryogenic distribution line in the LHC tunnel is finally finished! All the sectors have undergone pressure and helium leak tests at room temperature, and one complete sector was cold tested in cryogenic conditions. Some of the QRL team in UJ22 of the LHC tunnel, where the last sector of the cryogenic distribution line was installed.It must have been a joyous moment in UJ22 of the LHC tunnel (near Point 2, Saint Genis Pouilly) on 19 October. This was where the last external weld of the cryogenic distribution line, also known as QRL, was made, thus completing the full distribution ring. The QRL is a circle built in 8 sectors, each approximately 3 km in length. It will circulate helium in liquid and gas phases, at different temperatures and pressures, to provide the cryogenic conditions for the superconducting magnets in the LHC tunnel. The last sector installed (sector 1-2) passed the pressure and helium leak tests at room temperature on 28 October. As part of the warm test, each sector...

  17. Kastor-Traschen black holes, null geodesics and conformal circles

    International Nuclear Information System (INIS)

    Casey, Stephen

    2012-01-01

    The Kastor-Traschen metric is a time-dependent solution of the Einstein-Maxwell equations with positive cosmological constant Λ which can be used to describe an arbitrary number of charged dynamical black holes. In this paper, we consider the null geodesic structure of this solution, in particular, focusing on the projection to the space of orbits of the timelike conformal retraction. It is found that these projected light rays arise as integral curves of a system of third-order ordinary differential equations. This system is not uniquely defined, however, and we use the inherent freedom to construct a new system whose integral curves coincide with the projection of distinguished null curves of Kastor-Traschen arising from a magnetic flow. We discuss our results in the one-centre case and demonstrate a link to conformal circles in the limit Λ → 0. We also show how to construct analytic expressions for the projected null geodesics of this metric by exploiting a well-known diffeomorphism between the K-T metric and extremal Reissner-Nordstrom-de Sitter. We make some remarks about the two-centre solution and demonstrate a link with the one-centre case. (paper)

  18. Large-scale roll-to-roll photonic sintering of flexo printed silver nanoparticle electrodes

    DEFF Research Database (Denmark)

    Hösel, Markus; Krebs, Frederik C

    2012-01-01

    In this report we employ static and roll-to-roll (R2R) photonic sintering processes on flexo printed silver nanoparticle-based electrode structures with a heat-sensitive 60 mm thin barrier foil as a substrate. We use large area electrode structures to visualize the increased optical footprint...... as the nanoparticles are already sintered. The advantage of single exposure is the ability to produce higher R2R processing speeds without overlapping, which is shown in the form of theoretical calculations....

  19. Interlayer adhesion in roll-to-roll processed flexible inverted polymer solar cells

    DEFF Research Database (Denmark)

    Dupont, Stephanie R.; Oliver, Mark; Krebs, Frederik C

    2012-01-01

    demonstrate how a thin-film adhesion technique can be applied to flexible organic solar cells to obtain quantitative adhesion values. For the P3HT:PCBM-based BHJ polymer solar cells, the interface of the BHJ with the conductive polymer layer PEDOT:PSS was found to be the weakest. The adhesion fracture energy......The interlayer adhesion of roll-to-roll processed flexible inverted P3HT:PCBM bulk heterojunction (BHJ) polymer solar cells is reported. Poor adhesion between adjacent layers may result in loss of device performance from delamination driven by the thermomechanical stresses in the device. We...... energies was observed....

  20. High throughput in situ scattering of roll-to-roll coated functional polymer films

    DEFF Research Database (Denmark)

    Andreasen, Jens Wenzel

    2017-01-01

    The development of conjugated polymers for organic electronics and photovoltaics has relied heavily on advanced X-ray scattering techniques almost since the earliest studies in the field. Almost from the beginning, structural studies focused on how the polymers self-organize in thin films......, and the relation between chemical configuration of the polymer, structure and performance. This chapter presents the latest developments where structural analysis is applied as in situ characterization of structure formation during roll-to-roll coating of photoactive layers for solar cells....

  1. Roll-to-roll processed polymer tandem solar cells partially processed from water

    DEFF Research Database (Denmark)

    Larsen-Olsen, Thue Trofod; Andersen, Thomas Rieks; Andreasen, Birgitta

    2012-01-01

    Large area polymer tandem solar cells completely processed using roll-to-roll (R2R) coating and printing techniques are demonstrated. A stable tandem structure was achieved by the use of orthogonal ink solvents for the coating of all layers, including both active layers. Processing solvents...... included water, alcohols and chlorobenzene. Open-circuit voltages close to the expected sum of sub cell voltages were achieved, while the overall efficiency of the tandem cells was found to be limited by the low yielding back cell, which was processed from water based ink. Many of the challenges associated...

  2. Quality control of roll-to-roll processed polymer solar modules by complementary imaging methods

    DEFF Research Database (Denmark)

    Rösch, R.; Krebs, Frederik C; Tanenbaum, D.M.

    2012-01-01

    We applied complementary imaging methods to investigate processing failures of roll-to-roll solution processed polymer solar modules based on polymer:fullerene bulk heterojunctions. For investigation of processing deficiencies in solar modules we employed dark lock-in thermography (DLIT......), electroluminescence (ELI) and photoluminescence/reflection imaging (PLI/RI) complemented by optical imaging (OI). The combination of all high resolution images allowed us to allocate the origin of processing errors to a specific deposition process, i.e. the insufficient coverage of an electrode interlayer...

  3. The theory and technique of yamuna body rolling.

    Science.gov (United States)

    Suzuki, Satoshi

    2013-09-01

    [Purpose] This paper provides information about the theory and technique of Yamuna Body Rolling. In order to treat physical problems, using the specialized Yamuna Body Rolling balls, people can target superficial skin, fasciae, muscle fibers, tendons, ligaments, bones, internal organs, and the nervous system by themselves. The extraordinary effect of Yamuna Body Rolling is its multidimensional elongation of muscle fibers. In addition to the regular longitudinal elongation by the conventional stretch method, Yamuna Body Rolling enables the transversal and diagonal expansion of muscle fibers in order to move the body more dynamically. Hamstring, abdominal, and sideline routines are presented as examples for techniques of Yamuna Body Rolling. Yamuna Body Rolling can be applied to functional evaluation and therapeutic uses; therefore, it could provide many benefits in the treatment of different conditions in the medical field.

  4. Plastic anisotropy of straight and cross rolled molybdenum sheets

    International Nuclear Information System (INIS)

    Oertel, C.-G.; Huensche, I.; Skrotzki, W.; Knabl, W.; Lorich, A.; Resch, J.

    2008-01-01

    The microstructure, texture and mechanical properties of molybdenum sheets produced by different rolling processes were investigated by orientation imaging in the scanning electron microscope, X-ray diffraction and tensile tests, respectively. For comparable recrystallization degree of the sheets investigated, straight rolling with low reduction ratio produces α-fiber textures with a maximum at {100} . At higher rolling degrees the maximum shifts to {112} . Cross rolling increases the rotated cube component {100} . The strong differences in the texture measured are reflected in the plastic anisotropy characterized by differences in the yield stress and Lankford parameter which were measured along directions in the rolling plane at angles of 0 deg., 45 deg. and 90 deg. with the rolling direction. The Taylor-Bishop-Hill theory is used successfully to qualitatively explain the plastic anisotropy

  5. Prediction of Parametric Roll Resonance by Multilayer Perceptron Neural Network

    DEFF Research Database (Denmark)

    Míguez González, M; López Peña, F.; Díaz Casás, V.

    2011-01-01

    Parametric roll resonance is a ship stability related phenomenon that generates sudden large amplitude oscillations up to 30-40 degrees of roll. This can cause severe damage, and it can put the crew in serious danger. The need for a parametric rolling real time prediction system has been acknowle......Parametric roll resonance is a ship stability related phenomenon that generates sudden large amplitude oscillations up to 30-40 degrees of roll. This can cause severe damage, and it can put the crew in serious danger. The need for a parametric rolling real time prediction system has been...... acknowledged in the last few years. This work proposes a prediction system based on a multilayer perceptron (MP) neural network. The training and testing of the MP network is accomplished by feeding it with simulated data of a three degrees-of-freedom nonlinear model of a fishing vessel. The neural network...

  6. Manufacture of thin-walled clad tubes by pressure welding of roll bonded sheets

    Science.gov (United States)

    Schmidt, Hans Christian; Grydin, Olexandr; Stolbchenko, Mykhailo; Homberg, Werner; Schaper, Mirko

    2017-10-01

    Clad tubes are commonly manufactured by fusion welding of roll bonded metal sheets or, mechanically, by hydroforming. In this work, a new approach towards the manufacture of thin-walled tubes with an outer diameter to wall thickness ratio of about 12 is investigated, involving the pressure welding of hot roll bonded aluminium-steel strips. By preparing non-welded edges during the roll bonding process, the strips can be zip-folded and (cold) pressure welded together. This process routine could be used to manufacture clad tubes in a continuous process. In order to investigate the process, sample tube sections with a wall thickness of 2.1 mm were manufactured by U-and O-bending from hot roll bonded aluminium-stainless steel strips. The forming and welding were carried out in a temperature range between RT and 400°C. It was found that, with the given geometry, a pressure weld is established at temperatures starting above 100°C. The tensile tests yield a maximum bond strength at 340°C. Micrograph images show a consistent weld of the aluminium layer over the whole tube section.

  7. Behavioural evidence for a visual and proprioceptive control of head roll in hoverflies (Episyrphus balteatus).

    Science.gov (United States)

    Goulard, Roman; Julien-Laferriere, Alice; Fleuriet, Jérome; Vercher, Jean-Louis; Viollet, Stéphane

    2015-12-01

    The ability of hoverflies to control their head orientation with respect to their body contributes importantly to their agility and their autonomous navigation abilities. Many tasks performed by this insect during flight, especially while hovering, involve a head stabilization reflex. This reflex, which is mediated by multisensory channels, prevents the visual processing from being disturbed by motion blur and maintains a consistent perception of the visual environment. The so-called dorsal light response (DLR) is another head control reflex, which makes insects sensitive to the brightest part of the visual field. In this study, we experimentally validate and quantify the control loop driving the head roll with respect to the horizon in hoverflies. The new approach developed here consisted of using an upside-down horizon in a body roll paradigm. In this unusual configuration, tethered flying hoverflies surprisingly no longer use purely vision-based control for head stabilization. These results shed new light on the role of neck proprioceptor organs in head and body stabilization with respect to the horizon. Based on the responses obtained with male and female hoverflies, an improved model was then developed in which the output signals delivered by the neck proprioceptor organs are combined with the visual error in the estimated position of the body roll. An internal estimation of the body roll angle with respect to the horizon might explain the extremely accurate flight performances achieved by some hovering insects. © 2015. Published by The Company of Biologists Ltd.

  8. Engineering of rolled constructional microalloyed steel products

    International Nuclear Information System (INIS)

    Adamczyk, J.

    2003-01-01

    Flexibility of the microalloyed steels on manufacturing of products with high mechanical and technological properties at not exaggerated production costs, it caused of their application for different constructions and machines in many branches of economy. It is a reason of the big interest of this steel group and the improvement of metallurgical and technological processing. In the work the examples of applications of C-Mn microalloyed steels with V and N microadditions for production of long shape products of R p0.2 > 650 MPa and KCU2 > 57 Jcm -2 are presented. They are manufactured in the controlled rolling process. Moreover this work presents liquid metal treatment in ladlemann process and influence of ingots solidification conditions, controlled rolling of weldable plates with Nb, Ti, V and B microadditions which after quenching and tempering have R p0.2 > 870 MPa, KV -50 o C > 27 J and plastic strain ratio equals 1.2. This work also presents the energy saving rolling technology with controlled recrystallization (method of thermomechanical treatment) of improved Weldox 960 steel plates with Mb, Ti, V and B microadditions which have after high-temperature tempering R p0.2 > 100 MPa, KV -50 o C >90 J and plastic strain ratio is less than 1.2. The introduction of microalloyed constructional steels and the appropriate technology in the domestic industry will contribute to high-processed products with properties competitive to products manufactured in high-industrialized countries. Thanks to that it will be possible to increase the technical level as well as to reduce production costs and import. (author)

  9. Overlay accuracy on a flexible web with a roll printing process based on a roll-to-roll system.

    Science.gov (United States)

    Chang, Jaehyuk; Lee, Sunggun; Lee, Ki Beom; Lee, Seungjun; Cho, Young Tae; Seo, Jungwoo; Lee, Sukwon; Jo, Gugrae; Lee, Ki-yong; Kong, Hyang-Shik; Kwon, Sin

    2015-05-01

    For high-quality flexible devices from printing processes based on Roll-to-Roll (R2R) systems, overlay alignment during the patterning of each functional layer poses a major challenge. The reason is because flexible substrates have a relatively low stiffness compared with rigid substrates, and they are easily deformed during web handling in the R2R system. To achieve a high overlay accuracy for a flexible substrate, it is important not only to develop web handling modules (such as web guiding, tension control, winding, and unwinding) and a precise printing tool but also to control the synchronization of each unit in the total system. A R2R web handling system and reverse offset printing process were developed in this work, and an overlay between the 1st and 2nd layers of ±5μm on a 500 mm-wide film was achieved at a σ level of 2.4 and 2.8 (x and y directions, respectively) in a continuous R2R printing process. This paper presents the components and mechanisms used in reverse offset printing based on a R2R system and the printing results including positioning accuracy and overlay alignment accuracy.

  10. Spoilers for roll control of light airplanes

    Science.gov (United States)

    Roskam, J.; Kohlman, D. L.; Wentz, W. H.

    1974-01-01

    The paper presents an overview of the state-of-the-art of roll control spoilers for light airplanes. Reasons for using spoilers on light airplanes are presented. Several classical objections to the use of spoilers of such airplanes are critically examined. It is shown that mechanically driven spoiler systems can be designed. Flight test results of a new mechanically driven spoiler on the Redhawk airplane are discussed. Tunnel data of spoilers on the new general aviation airfoil GA(W)-1 are presented. Finally, a bibliography on spoiler data is included.

  11. Rolling Bearing Life Prediction, Theory, and Application

    Science.gov (United States)

    Zaretsky, Erwin V.

    2016-01-01

    A tutorial is presented outlining the evolution, theory, and application of rolling-element bearing life prediction from that of A. Palmgren, 1924; W. Weibull, 1939; G. Lundberg and A. Palmgren, 1947 and 1952; E. Ioannides and T. Harris, 1985; and E. Zaretsky, 1987. Comparisons are made between these life models. The Ioannides-Harris model without a fatigue limit is identical to the Lundberg-Palmgren model. The Weibull model is similar to that of Zaretsky if the exponents are chosen to be identical. Both the load-life and Hertz stress-life relations of Weibull, Lundberg and Palmgren, and Ioannides and Harris reflect a strong dependence on the Weibull slope. The Zaretsky model decouples the dependence of the critical shear stress-life relation from the Weibull slope. This results in a nominal variation of the Hertz stress-life exponent. For 9th- and 8th-power Hertz stress-life exponents for ball and roller bearings, respectively, the Lundberg-Palmgren model best predicts life. However, for 12th- and 10th-power relations reflected by modern bearing steels, the Zaretsky model based on the Weibull equation is superior. Under the range of stresses examined, the use of a fatigue limit would suggest that (for most operating conditions under which a rolling-element bearing will operate) the bearing will not fail from classical rolling-element fatigue. Realistically, this is not the case. The use of a fatigue limit will significantly overpredict life over a range of normal operating Hertz stresses. (The use of ISO 281:2007 with a fatigue limit in these calculations would result in a bearing life approaching infinity.) Since the predicted lives of rolling-element bearings are high, the problem can become one of undersizing a bearing for a particular application. Rules had been developed to distinguish and compare predicted lives with those actually obtained. Based upon field and test results of 51 ball and roller bearing sets, 98 percent of these bearing sets had acceptable

  12. Entry Strategies to Indonesian Market Case: MoveaRoll

    OpenAIRE

    Islam, Zahedul

    2013-01-01

    MoveRoll Oy, an internationally growing and expanding Finnish company located in Porvoo, has invented a unique technology to produce a paper roll conveyor which the company believes will revolutionise the paper roll handling industry. Moreover, after establishing itself in the Finnish market, the company has started expanding its business to countries like Sweden, USA, and China. Likewise, the process of expanding to the Russian market is currently underway and the company has recently launch...

  13. Adaptive attenuation of aliased ground roll using the shearlet transform

    Science.gov (United States)

    Hosseini, Seyed Abolfazl; Javaherian, Abdolrahim; Hassani, Hossien; Torabi, Siyavash; Sadri, Maryam

    2015-01-01

    Attenuation of ground roll is an essential step in seismic data processing. Spatial aliasing of the ground roll may cause the overlap of the ground roll with reflections in the f-k domain. The shearlet transform is a directional and multidimensional transform that separates the events with different dips and generates subimages in different scales and directions. In this study, the shearlet transform was used adaptively to attenuate aliased and non-aliased ground roll. After defining a filtering zone, an input shot record is divided into segments. Each segment overlaps adjacent segments. To apply the shearlet transform on each segment, the subimages containing aliased and non-aliased ground roll, the locations of these events on each subimage are selected adaptively. Based on these locations, mute is applied on the selected subimages. The filtered segments are merged together, using the Hanning function, after applying the inverse shearlet transform. This adaptive process of ground roll attenuation was tested on synthetic data, and field shot records from west of Iran. Analysis of the results using the f-k spectra revealed that the non-aliased and most of the aliased ground roll were attenuated using the proposed adaptive attenuation procedure. Also, we applied this method on shot records of a 2D land survey, and the data sets before and after ground roll attenuation were stacked and compared. The stacked section after ground roll attenuation contained less linear ground roll noise and more continuous reflections in comparison with the stacked section before the ground roll attenuation. The proposed method has some drawbacks such as more run time in comparison with traditional methods such as f-k filtering and reduced performance when the dip and frequency content of aliased ground roll are the same as those of the reflections.

  14. Effect of rolling reduction on the development of rolling and recrystallization textures in Al-Mg alloys

    Energy Technology Data Exchange (ETDEWEB)

    Endou, S; Inagaki, H [Shonan Inst. of Tech., Fujisawashi (Japan)

    2002-07-01

    In order to investigate the effect of Mg content on the development of the rolling textures in Al pure Al, Al-3% Mg alloy and Al-5% Mg alloy were cold rolled by varying rolling reductions up to 97%. Their rolling textures were investigated by the orientation distribution function analysis. The extent of work hardening introduced by cold rolling was estimated by the hardness measurements. It was found that, at all rolling reductions, the main orientations of the rolling textures depended strongly on the Mg content. In pure Al, {l_brace}123{r_brace} left angle 634 right angle was always the main orientation, whereas {l_brace}112{r_brace} left angle 111 right angle was most strong in the Al-3%Mg alloy. In the Al-5% Mg alloy, the development of both {l_brace}123{r_brace} left angle 634 right angle and {l_brace}112{r_brace} left angle 111 right angle were strongly suppressed, whereas {l_brace}110{r_brace} left angle 112 right angle developed remarkably. In pure Al, most of the texture development occurred at the later half of work hardening, i.e. at rolling reductions above 70%. With increasing Mg content, rolling texture tended to develop already at lower rolling reductions. Dynamic recovery, which occurred at very high rolling reductions, suppressed the development of the rolling textures. All these results strongly suggested that the formation of dislocation cell structures and shear banding are origins of the formation of these rolling textures. On annealing these specimens at 450 C for 30 min, recrystallization textures developed only in specimens having strong rolling textures, i. e. in the specimens cold rolled more than 70%. {l_brace}100{r_brace} left angle 001 right angle developed only in pure Al and in the Al-3% Mg ally, in which {l_brace}123{r_brace} left angle 634 right angle and {l_brace}112{r_brace} left angle 111 right angle were strong in the rolling textures. Recrystallization textures of the Al-5% Mg alloy was wather random. Its main orientation, {l

  15. Superhydrophobic Properties of Nanotextured Polypropylene Foils Fabricated by Roll-to-Roll Extrusion Coating

    DEFF Research Database (Denmark)

    Telecka, Agnieszka; Murthy, Swathi; Sun, Ling

    2016-01-01

    etching with different processing gas flow rates. We provide a systematic study of the wetting properties for the fabricated surfaces and show that a controlled texture stretching effect in the R2R-EC process is instrumental to yield the superhydrophobic surfaces with water contact angles approaching 160......° and droplet roll-off angles below 10°....

  16. Thermal Characteristics of Plastic Film Tension in Roll-to-Roll Gravure Printed Electronics

    Directory of Open Access Journals (Sweden)

    Kui He

    2018-02-01

    Full Text Available In the printing section of a roll-to-roll gravure printed electronics machine, the plastic film tension is directly associated with the product quality. The temperature distribution of the plastic film in the printing section is non-uniform, because of the higher drying temperature and the lower room temperature. Furthermore, the drying temperature and the room temperature are not constants in industrial production. As the plastic film is sensitive to temperature, the temperature of the plastic film will affects the web tension in the printing section. In this paper, the thermal characteristics of the plastic film tension in roll-to-roll gravure printed electronics are studied in order to help to improve the product quality. First, the tension model including the factor of temperature is derived based on the law of mass conservation. Then, some simulations and experiments are carried out in order to in-depth research the effects of the drying temperature and room temperature based on the relations between system inputs and outputs. The results show that the drying temperature and room temperature have significant influences on the web tension. The research on the thermal characteristics of plastic film tension would benefit the tension control accuracy for further study.

  17. Self-Aligned Metal Electrodes in Fully Roll-to-Roll Processed Organic Transistors

    Directory of Open Access Journals (Sweden)

    Marja Vilkman

    2016-01-01

    Full Text Available We demonstrate the production of organic bottom gate transistors with self-aligned electrodes, using only continuous roll-to-roll (R2R techniques. The self-alignment allows accurate <5 µm layer-to-layer registration, which is usually a challenge in high-speed R2R environments as the standard registration methods are limited to the millimeter range—or, at best, to tens of µm if online cameras and automatic web control are utilized. The improved registration enables minimizing the overlap between the source/drain electrodes and the gate electrode, which is essential for minimizing the parasitic capacitance. The complete process is a combination of several techniques, including evaporation, reverse gravure, flexography, lift-off, UV exposure and development methods—all transferred to a continuous R2R pilot line. Altogether, approximately 80 meters of devices consisting of thousands of transistors were manufactured in a roll-to-roll fashion. Finally, a cost analysis is presented in order to ascertain the main costs and to predict whether the process would be feasible for the industrial production of organic transistors.

  18. Development of an aerostatic bearing system for roll-to-roll printed electronics

    Science.gov (United States)

    Chen, Shasha; Chen, Weihai; Liu, Jingmeng; Chen, Wenjie; Jin, Yan

    2018-06-01

    Roll-to-roll printed electronics is proved to be an effective way to fabricate electrical devices on various substrates. High precision overlay alignment plays a key role to create multi-layer electrical devices. Multiple rollers are adopted to support and transport the substrate web. In order to eliminate the negative effect of the machining error and assembling error of the roller, a whole roll-to-roll system including two aerostatic bearing devices with arrayed restrictors is proposed in this paper. Different to the conventional roller, the aerostatic bearing device can create a layer of air film between the web and the device to realize non-contact support and transport. Based on simplified Navier–Stokes equations, the theoretical model of the air film is established. Moreover, the pressure distribution of the whole flow field and single restrictor in different positions are modeled by conducting numerical simulation with computational fluid dynamics (CFD) software FLUENT. The load capacity curves and stiffness curves are generated to provide guidance for optimizing the structure of the device. A prototype of the aerostatic bearing system is set up and the experiment tests are carried out. For the proposed aerostatic bearing roller with a diameter of 100 mm and length of 200 mm, the experimental results show the aerostatic bearing method can achieve the position accuracy in a range of 1 μm in the vertical direction of the web, which is much better than that using existing methods.

  19. Multi-level approach for parametric roll analysis

    Science.gov (United States)

    Kim, Taeyoung; Kim, Yonghwan

    2011-03-01

    The present study considers multi-level approach for the analysis of parametric roll phenomena. Three kinds of computation method, GM variation, impulse response function (IRF), and Rankine panel method, are applied for the multi-level approach. IRF and Rankine panel method are based on the weakly nonlinear formulation which includes nonlinear Froude- Krylov and restoring forces. In the computation result of parametric roll occurrence test in regular waves, IRF and Rankine panel method show similar tendency. Although the GM variation approach predicts the occurrence of parametric roll at twice roll natural frequency, its frequency criteria shows a little difference. Nonlinear roll motion in bichromatic wave is also considered in this study. To prove the unstable roll motion in bichromatic waves, theoretical and numerical approaches are applied. The occurrence of parametric roll is theoretically examined by introducing the quasi-periodic Mathieu equation. Instability criteria are well predicted from stability analysis in theoretical approach. From the Fourier analysis, it has been verified that difference-frequency effects create the unstable roll motion. The occurrence of unstable roll motion in bichromatic wave is also observed in the experiment.

  20. Development of a Minimally Actuated Jumping-Rolling Robot

    Directory of Open Access Journals (Sweden)

    Thanhtam Ho

    2015-04-01

    Full Text Available This paper presents development of a hybrid mobile robot in order to take advantage of both rolling and jumping locomotion on the ground. According to the unique design of the mechanism, the robot is able to execute both jumping and rolling skilfully by using only one DC motor. Changing the centre of gravity enables rolling of the robot and storage of energy is utilized for jumping. Mechanism design and control logic are validated by computer simulation. Simulation results show that the robot can jump nearly 1.3 times its diameter and roll at the speed of 3.3 times its diameter per second.

  1. Early Detection of Parametric Roll Resonance on Container Ships

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Blanke, Mogens; Poulsen, Niels Kjølstad

    2013-01-01

    Parametric roll resonance on ships is a nonlinear phenomenon where waves encountered at twice the natural roll frequency can bring the vessel dynamics into a bifurcation mode and lead to extreme values of roll. Recent years have seen several incidents with dramatic damage to container vessels...... the ship's speed and course, to escape from the bifurcation condition. This paper proposes nonparametric methods to detect the onset of roll resonance and demonstrates their performance. Theoretical conditions for parametric resonance are revisited and are used to develop efficient methods to detect its...... on experimental data from model tests and on data from a container ship crossing the Atlantic during a storm....

  2. An advanced dissymmetric rolling model for online regulation

    Science.gov (United States)

    Cao, Trong-Son

    2017-10-01

    Roll-bite model is employed to predict the rolling force, torque as well as to estimate the forward slip for preset or online regulation at industrial rolling mills. The rolling process is often dissymmetric in terms of work-rolls rotation speeds and diameters as well as the friction conditions at upper and lower contact surfaces between work-rolls and the strip. The roll-bite model thus must be able to account for these dissymmetries and in the same time has to be accurate and fast enough for online applications. In the present study, a new method, namely Adapted Discretization Slab Method (ADSM) is proposed to obtain a robust roll-bite model, which can take into account the aforementioned dissymmetries and has a very short response time, lower than one millisecond. This model is based on the slab method, with an adaptive discretization and a global Newton-Raphson procedure to improve the convergence speed. The model was validated by comparing with other dissymmetric models proposed in the literature, as well as Finite Element simulations and industrial pilot trials. Furthermore, back-calculation tool was also constructed for friction management for both offline and online applications. With very short CPU time, the ADSM-based model is thus attractive for all online applications, both for cold and hot rolling.

  3. Rolling induced size effects in elastic–viscoplastic sheet metals

    DEFF Research Database (Denmark)

    Nielsen, Kim Lau

    2015-01-01

    sheet rolling, where a non-homogeneous material deformation takes place between the rollers. Large strain gradients develop where the rollers first come in contact with the sheet, and a higher order plasticity model is employed to illustrate their influence at small scales. The study reveals...... presented revolves around the rolling induced effect of visco-plasticity (ranging hot and cold rolling) in combination with strain gradient hardening – including both dissipative and energetic contributions. To bring out first order effects on rolling at small scale, the modeling efforts are limited to flat...

  4. Annuitants Added to the Annuity Roll Processing System (ARPS)

    Data.gov (United States)

    Office of Personnel Management — Small table showing the total Civil Service Retirement System (CSRS) and Federal Employees Retirement System (FERS) Annuitants added to the Annuity Roll Processing...

  5. Rolling Deck to Repository II: Getting Control of Provenance and Quality

    Science.gov (United States)

    Miller, S. P.; Arko, R.; Chandler, C. L.; Clark, P. D.; Neiswender, C.

    2008-12-01

    Data are now being re-used by a far wider circle of researchers and students than ever before, across a broader range of disciplines. Before, during, and after a field program, the exchange and merging of information is a dynamic, iterative and sometimes anonymous process that may occur years, or decades, after the data were initially acquired. Collaborative steps are currently being taken toward a prototype data discovery system that can be extended to the entire NSF-supported academic research fleet, including both large and small operations. With emerging shipboard Internet capabilities, near real-time transport of selected data from the rolling deck to a repository can become a reality. Much of the effort is being devoted to data preservation and access, to the identification of standard products, and to the generation of appropriate metadata, with a streamlined methodology that can be adopted by a wide range of vessel operating institutions. Beyond the challenge of just finding data, currently researchers and students struggle repeatedly to make sense of downloaded data objects. Across institutions there are wide variations in quality control procedures, most commonly none, and virtually no external communication of the history of transformations applied to a data set. For example, the status of corrections for sound velocity or roll-bias, or beampoint editing for multibeam swath seafloor mapping sonar systems are often challenging to experts and baffling to users from other disciplines. With greater re-use of data comes the greater likelihood of interpretation of artifacts as features. Tracking data provenance and quality is a problem today, and the situation will become more critical as data are more widely and rapidly disseminated. We will identify quality control criteria for standard shipboard data products, and existing tools for quality assessment with automation potential (or lack thereof). We invite discussion of an XML institutional quality

  6. METHODOLOGICAL FUNDAMENTALS OF DETERMINATION OF UNPOWERED ROLLING STOCK MAINTENANCE CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    L. A. Muradian

    2016-02-01

    Full Text Available Purpose. The paper involves: 1 confirmation of the technical characteristics of cars and their modifications, as well as indicators of unfailing work probability during the time between overhauls or service hours; 2 improving the methodological approaches to assess the maintenance characteristics of new and modernized equipment of rail transport on the example of not self-propelled rolling stock, namely, railway freight cars; 3 solution of scientific and applied problems in assessment the maintenance characteristics of the new and modernized railway equipment. Methodology. The basic methodological approaches to the assessment of the maintenance characteristics on the example of not self-propelled rolling stock, namely, railway freight cars were considered. The analysis of the reliability of the car, which is considered as a complex mechanical system, where all system elements are connected in series, wherein each element includes m is serially connected parts. The failure of each part of the calculation will result in refusal of the car. Thus, the car is a system without redundancy. Findings. The evaluation technic of the maintenance characteristics of freight cars in controlled operation with taking into account the features of the new generation of cars was improved. Specified: the duration of the tests, the frequency of inspection of the control group of cars controlled by the parameters of the car, the reasons for the early termination of controlled operation. Identified failures in the process of controlled operation are divided according to their nature. Originality. The authors proposed a method of assessing the maintenance characteristics of railway equipment in trial operation as an example of a new generation of freight cars. Practical value. The results allow assessing the maintenance characteristics of new and modernized rail transport equipment during the maintenance test.

  7. Fabrication of Superhydrophobic Metallic Surface by Wire Electrical Discharge Machining for Seamless Roll-to-Roll Printing

    Directory of Open Access Journals (Sweden)

    Jin-Young So

    2018-04-01

    Full Text Available This paper presents a proposal of a direct one-step method to fabricate a multi-scale superhydrophobic metallic seamless roll mold. The mold was fabricated using the wire electrical discharge machining (WEDM technique for a roll-to-roll imprinting application to produce a large superhydrophobic surface. Taking advantage of the exfoliating characteristic of the metallic surface, nano-sized surface roughness was spontaneously formed while manufacturing the micro-sized structure: that is, a dual-scale hierarchical structure was easily produced in a simple one-step fabrication with a large area on the aluminum metal surface. This hierarchical structure showed superhydrophobicity without chemical coating. A roll-type seamless mold for the roll-to-roll process was fabricated through engraving the patterns on the cylindrical substrate, thereby enabling to make a continuous film with superhydrophobicity.

  8. Study Circles in Online Learning Environment in the Spirit of Learning-Centered Approach

    Directory of Open Access Journals (Sweden)

    Simándi Szilvia

    2017-08-01

    Full Text Available Introduction: In the era of information society and knowledge economy, learning in non-formal environments gets a highlighted role: it can supplement, replace or raise the knowledge and skills gained in the school system to a higher level (Forray & Juhász, 2008, as the so-called “valid” knowledge significantly changes due to the acceleration of development. With the appearance of information technology means and their booming development, the possibilities of gaining information have widened and, according to the forecasts, the role of learning communities will grow. Purpose: Our starting point is that today, with the involvement of community sites (e.g. Google+, Facebook etc. there is a new possibility for inspiring learning communities: by utilizing the power of community and the possibilities of network-based learning (Ollé & Lévai, 2013. Methods: We intend to make a synthesis based on former research and literature focusing on the learning-centered approach, online learning environment, learning communities and study circles (Noesgaard & Ørngreen, 2015; Biggs & Tang, 2007; Kindström, 2010 Conclusions: The online learning environment can be well utilized for community learning. In the online learning environment, the process of learning is built on activity-oriented work for which active participation, and an intensive, initiative communication are necessary and cooperative and collaborative learning get an important role.

  9. "Let the Circle be Unbroken" helps African-Americans prevent teen pregnancy.

    Science.gov (United States)

    Okwumabua, T M; Okwumabua, J O; Elliott, V

    1998-01-01

    Strategies must be developed to address the high rate of adolescent pregnancy among Blacks in the US and the adverse consequences of premature parenting. A number of programs and strategies have been developed and are being implemented in various sites across the US. The "Let the Circle Be Unbroken: Rites of Passage" program is an effort to incorporate an Afrocentric conceptual model into a prevention program. It involves adapting socialization processes often observed in African cultures, which openly acknowledge the need to formally help adolescents during their transition from childhood to adulthood. That socialization process tends to be a cultural experience which requires that ideology, education, training, and culture be taught before an activity or celebration marking the successful transition from one stage of development to another. The "Rites of Passage" approach follows these basic premises to teach adolescents the knowledge and skills needed to become responsible community members and spiritually mature adults. It is specifically designed to help young people build self-esteem; enhance self-image; develop leadership skills, cultural awareness, and appreciation; and make healthy, productive, and self-affirming life choices.

  10. Transverse self-fields within an electron bunch moving in an arc of a circle

    International Nuclear Information System (INIS)

    Geloni, G.; Botman, J.; Luiten, J.; Wiel, M. van der; Yurkov, M.V.

    2002-04-01

    As a consequence of motions driven by external forces, self-fields (which are different from the static case) originate within an electron bunch. In the case of magnetic external forces acting on an ultrarelativistic beam, the longitudinal self-interactions are responsible for CSR (coherent synchrotron radiation)-related phenomena, which have been studied extensively. On the other hand, transverse self-interactions are present too. At the time being, existing theoretical analysis of transverse self-forces deal with the case of a bunch moving along a circular orbit only, without considering the situation of a bending magnet with a finite length. In this paper we propose an electrodynamical analysis of transverse self-fields which originate, at the position of a test particle, from an ultrarelativistic electron bunch moving in an arc of a circle. The problem will be first addressed within a two-particle system. We then extend our consideration to a line bunch with a stepped density distribution, a situation which can be easily generalized to the case of an arbitrary density distribution. Our approach turns out to be also useful in order to get a better insight in the physics involved in the case of simple circular motion and in order to address the well known issue of the partial compensation of transverse self-force. (orig.)

  11. Axial Force Analysis and Roll Contour Configuration of Four-High CVC Mill

    Directory of Open Access Journals (Sweden)

    Guang-ming Liu

    2018-01-01

    Full Text Available In order to analyze the influence of technical parameters on work roll axial force of four-high continuous variable crown (CVC mill, the deformation analyzing model with top roll system and strip was established based on influence function method. Then a CVC work roll curve designing scheme was proposed and it was carried out on some cold rolling mill considering the requirement of comprehensive work roll axial force minimization. The status of comprehensive work roll axial force is improved considering the rolling schedule that is beneficial to the roller bearing. Corresponding to the newly designed work roll contour, the backup roll end chamfer was designed considering comprehensive performance of interroll stress concentration, comprehensive work roll axial force, and strip shape control ability. The distribution of roll wear with newly designed backup roll contour is more even according to the field application data. The newly established roll configuration scheme is beneficial to four-high CVC mill.

  12. Rich services in interoperable Learning Designs: can the circle be squared?

    OpenAIRE

    Griffiths, David

    2009-01-01

    Griffiths, D. (2009). Rich services in interoperable Learning Designs: Can the circle be squared?. Presented at Opening Up Learning Design, European LAMS and Learning Design Conference 2009. July, 6-9, 2009, Milton Keynes, United Kingdom.

  13. Pied de pulse: packing embroidered circles and coil actuators in pied de poule (houndstooth)

    NARCIS (Netherlands)

    Feijs, L.M.G.; Toeters, M.J.; Torrence, E.; Torrence, B.; Sequin, C.; McKenna, D.; Fenyvesi, K.; Sarhangi, R.

    2016-01-01

    We report on the integration of fractal-like structures inspired by Appolonian circles with pied de poule (houndstooth) fabric patterns, and on the use of electric actuators in garments made with digital embroidery techniques.

  14. Visual Thinking, Algebraic Thinking, and a Full Unit-Circle Diagram.

    Science.gov (United States)

    Shear, Jonathan

    1985-01-01

    The study of trigonometric functions in terms of the unit circle offer an example of how students can learn algebraic relations and operations while using visually oriented thinking. Illustrations are included. (MNS)

  15. College geometry an introduction to the modern geometry of the triangle and the circle

    CERN Document Server

    Altshiller-Court, Nathan

    2007-01-01

    The standard university-level text for decades, this volume offers exercises in construction problems, harmonic division, circle and triangle geometry, and other areas. 1952 edition, revised and enlarged by the author.

  16. Interference of guiding modes in 'traffic' circle waveguides composed of dielectric spherical particles

    International Nuclear Information System (INIS)

    Polishchuk, I.Ya.; Gozman, M.I.; Samoylova, O.M.; Burin, A.L.

    2009-01-01

    The interference of guiding polariton modes propagating through the waveguide composed of dielectric spherical particles forming a 'traffic' circle docked by two linear entrance and exit chains is investigated. The dependence of intensity of the polariton wave on the position of the particle on the circle was studied using the multisphere Mie scattering formalism. We show that, if the frequency of light belongs to the pass-band of the circular part of this waveguide, the electromagnetic waves may be considered as two optical beams running along the circle in opposite directions and interfering with each other. Indeed, the obtained intensity behavior can be represented as a simple superposition of two waves propagating along the circle in opposite directions. The applications of this interference are discussed

  17. Violence in the eye of adolescents: education intervention with Culture Circles.

    Science.gov (United States)

    Brandão Neto, Waldemar; Silva, Marta Angélica Iossi; de Aquino, Jael Maria; de Lima, Luciane Soares; Monteiro, Estela Maria Leite Meirelles

    2015-01-01

    to apply the methodology of Culture Circles on adolescents as a strategy for health education of nurses in the construction of the collective knowledge of the thematic violence. action research type and qualitative study. Participants were 11 adolescents from a public school in Recife, PE, Brazil. Data production in Culture Circles included the participant observation with field diary, photographic recording and filming, as well as the photovoice technique. The analysis was performed by triangulating data in dialogue with the literature. it was shown that the problematizing action provided by the Culture Circle made possible to create situations in which adolescents felt invited to critically refl ect on the phenomenon of violence in all its complexity. the health education intervention, performed by Culture Circles, added learning and mutual growth subsidizing nursing care actions that excel at leadership and autonomy of adolescents.

  18. Collateral Circles in Carotid Artery Occlusion. A Comparative Study between CW Doppler and contrast angiography

    Energy Technology Data Exchange (ETDEWEB)

    Giraldi, C; Marconi, F; Parenti, G; Lenzi, B; Canapicchi, R; Padolecchia, R

    1986-01-01

    In order to evaluate the presence and efficacy of the different collateral circles, 98 patients with occlusion of the internal carotid artery between its origin and the origin of the ophtalmic artery, has been examined. Before contrast angiography, each patients was submitted to a Doppler examination with test of compression on the exsternal and common carotid arteries. The information on the collateral circles (Willis and pre-Willis) deriving from the Doppler examination seems to be interesting and more accurate. On the contrary, angiography allows a better visualisation of the extention of intercranial circles. These data show that the Doppler and angiographic techniques are complementary one to the other in the study of the collateral circles.

  19. Fermi Coordinates of an Observer Moving in a Circle in Minkowski Space: Apparent Behavior of Clocks

    National Research Council Canada - National Science Library

    Bahder, Thomas

    2000-01-01

    Space-time coordinate transformations valid for arbitrarily long coordinate time are derived from global Minkowski coordinates to the Fermi coordinates of an observer moving in a circle in three-dimensional space...

  20. Quasi-human seniority-order algorithm for unequal circles packing

    International Nuclear Information System (INIS)

    Zhu, Dingju

    2016-01-01

    In the existing methods for solving unequal circles packing problems, the initial configuration is given arbitrarily or randomly, but the impact of different initial configurations for existing packing algorithm to the speed of existing packing algorithm solving unequal circles packing problems is very large. The quasi-human seniority-order algorithm proposed in this paper can generate a better initial configuration for existing packing algorithm to accelerate the speed of existing packing algorithm solving unequal circles packing problems. In experiments, the quasi-human seniority-order algorithm is applied to generate better initial configurations for quasi-physical elasticity methods to solve the unequal circles packing problems, and the experimental results show that the proposed quasi-human seniority-order algorithm can greatly improve the speed of solving the problem.

  1. Citizenship as individual responsibility through personal investment - an ethnographic study in a study circle

    Directory of Open Access Journals (Sweden)

    Annika Pastuhov

    2017-05-01

    Full Text Available The aim of this article is to shed light on how the democratic ideal of institutionalised Nordic popular education is realised through an ethnographic field study in an English as a foreign language study circle. The study focuses on how participants express their citizenship when taking part in the study circle. Citizenship is viewed as a dynamic concept comprising the aspects of 'being' and 'acting' and constructed in and through social interaction. The study circle is arranged as a classroom practice: The study circle leader organises the activities, while the participants engage in exercises and attempt to learn correct usage. Through their participation, the participants take individual responsibility for what they see as their lack of sufficient knowledge of English. The participants describe their participation as a personal and voluntary investment in themselves. In light of the study, the individual stance is discussed as limiting possibilities for responsibility and thus expressions of citizenship.

  2. Reactive boundary layers in metallic rolling contacts

    Energy Technology Data Exchange (ETDEWEB)

    Burbank, John

    2016-05-01

    of the treated materials. The second pre-conditioning method involved the targeted generation of chemically reactive tribolayers (tribofilms) on twin disk testing rigs. The lubrication strategies were based on: a. CaCO{sub 3}, which is predominant in engine oils, and b. MoDTC, which is commonly used in engine and gear oils. The films generated in pre-conditioning were analyzed by SEM-EDX with Element-Mapping, Raman spectroscopy, and XPS to elucidate their molecular composition and concentration on the sample surfaces. The combination of these methods of analysis gave a clear indication that 10{sup 4} cycles were sufficient to generate stable and lasting tribofilms. CaO and CaCO{sub 3} were the main components of the tribofilm from the first lubricant package, while MoS{sub 2}, MoO{sub 2} and MoO{sub 3} were the main components from the second lubricant package. Finally, slip-rolling endurance testing (T = +120 C, 10{sup 7} cycles, approximately 19 days in a factory fill engine oil) was carried out on all materials. It was shown that both pre-conditioning methods could achieve significant reductions in friction and wear during testing at up to and including P{sub 0Mean} =1.94 GPa (P{sub 0Max} = 2.91 GPa, F{sub N} = 2,000 N). Ultimately, this research showed that: 1. non-case-hardened high-performance steels offer competitive wear performance and better friction behaviour than the case-hardened 20MnCr5. 2. pre-conditioning led to COF reductions to under 7/10 and wear coefficient reductions to an astonishing 1/10 of the original values for the untreated steels under mixed/boundary lubrication. 3. the observed improvements to friction behaviour and wear performance are indicative of a technically simple, cost- and energy-efficient pre-conditioning strategy that may prove an appropriate substitute for existing thermochemical treatments for steel alloys.

  3. Reactive boundary layers in metallic rolling contacts

    International Nuclear Information System (INIS)

    Burbank, John

    2016-01-01

    treated materials. The second pre-conditioning method involved the targeted generation of chemically reactive tribolayers (tribofilms) on twin disk testing rigs. The lubrication strategies were based on: a. CaCO 3 , which is predominant in engine oils, and b. MoDTC, which is commonly used in engine and gear oils. The films generated in pre-conditioning were analyzed by SEM-EDX with Element-Mapping, Raman spectroscopy, and XPS to elucidate their molecular composition and concentration on the sample surfaces. The combination of these methods of analysis gave a clear indication that 10 4 cycles were sufficient to generate stable and lasting tribofilms. CaO and CaCO 3 were the main components of the tribofilm from the first lubricant package, while MoS 2 , MoO 2 and MoO 3 were the main components from the second lubricant package. Finally, slip-rolling endurance testing (T = +120 C, 10 7 cycles, approximately 19 days in a factory fill engine oil) was carried out on all materials. It was shown that both pre-conditioning methods could achieve significant reductions in friction and wear during testing at up to and including P 0Mean =1.94 GPa (P 0Max = 2.91 GPa, F N = 2,000 N). Ultimately, this research showed that: 1. non-case-hardened high-performance steels offer competitive wear performance and better friction behaviour than the case-hardened 20MnCr5. 2. pre-conditioning led to COF reductions to under 7/10 and wear coefficient reductions to an astonishing 1/10 of the original values for the untreated steels under mixed/boundary lubrication. 3. the observed improvements to friction behaviour and wear performance are indicative of a technically simple, cost- and energy-efficient pre-conditioning strategy that may prove an appropriate substitute for existing thermochemical treatments for steel alloys.

  4. Progress in cold roll bonding of metals

    International Nuclear Information System (INIS)

    Li Long; Nagai, Kotobu; Yin Fuxing

    2008-01-01

    Layered composite materials have become an increasingly interesting topic in industrial development. Cold roll bonding (CRB), as a solid phase method of bonding same or different metals by rolling at room temperature, has been widely used in manufacturing large layered composite sheets and foils. In this paper, we provide a brief overview of a technology using layered composite materials produced by CRB and discuss the suitability of this technology in the fabrication of layered composite materials. The effects of process parameters on bonding, mainly including process and surface preparation conditions, have been analyzed. Bonding between two sheets can be realized when deformation reduction reaches a threshold value. However, it is essential to remove surface contamination layers to produce a satisfactory bond in CRB. It has been suggested that the degreasing and then scratch brushing of surfaces create a strong bonding between the layers. Bonding mechanisms, in which the film theory is expressed as the major mechanism in CRB, as well as bonding theoretical models, have also been reviewed. It has also been showed that it is easy for fcc structure metals to bond compared with bcc and hcp structure metals. In addition, hardness on bonding same metals plays an important part in CRB. Applications of composites produced by CRB in industrial fields are briefly reviewed and possible developments of CRB in the future are also described. Corrections were made to the abstract and conclusion of this article on 18 June 2008. The corrected electronic version is identical to the print version. (topical review)

  5. Advanced cold rolled steels for automotive applications

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, Harald; Mattissen, Dorothea; Schaumann, Thomas Wilhelm [ThyssenKrupp Steel AG, Center of Materials Excellence, Dortmund (Germany)

    2009-01-15

    Advanced high-strength steels offer a great potential for the further development of automobile bodies-in-white due to their combined mechanical properties of high formability and strength. They represent the first choice in material selection for strength and crash-relevant parts with challenging geometries. The intensive development of multiphase steels by ThyssenKrupp Steel has led to hot dip galvanizing concepts with an outstanding forming potential. Hot rolled, hot dip galvanized complex-phase steels are currently produced in addition to cold rolled dual phase (DP) and retained austenite (RA) or transformation induced plasticity (TRIP) steels. New continuously annealed grades of steel are being developed with tensile strength levels of up to 1000 MPa in combination with sufficient ductility for the high demands of structural automobile components. These steels make use of the classic advantages of microalloying as well as the principles of DP steels and RA / TRIP steels. Further improvement of properties will be reached by the new class of high manganese alloyed steels. (orig.)

  6. Wear of rolling element bearings in sodium

    International Nuclear Information System (INIS)

    Campbell, C.S.

    1976-01-01

    Rolling element bearings and related mechanisms are attractive for service in liquid sodium but it is not clear what minimum wear rate can be anticipated. For axially loaded angular contact bearings rotation is incompatible with pure rolling on both races and wear arises from the resulting ball spin. The initial pressure distributions and sizes of the contact ellipses can be calculated but will change with bearing wear. However, the most effective distribution for producing wear would be for the full loads to be borne on the tips of the contact areas, whose maximum length is given by examination of the race wear tracks. A calculation on such a basis should set a lower limit for the wear coefficient. Both the torque and instantaneous wear rate of a bearing will be similar functions of the integral over the contact areas of the product of contact pressure and radius from the ball spin axis. A better estimate of wear coefficient should be obtained by relating the average torque, the average wear, the initial torque and the initial wear where the conditions are known. Analysis of tests in sodium at 400 0 C of high speed steel and Stellite bearings by these methods indicates specific wear rates of the order of 10 -15 m 3 /N-m, not unduly out of line with the range of values found in conventional sliding tests

  7. Complex motion of elevators in piecewise map model combined with circle map

    Science.gov (United States)

    Nagatani, Takashi

    2013-11-01

    We study the dynamic behavior in the elevator traffic controlled by capacity when the inflow rate of passengers into elevators varies periodically with time. The dynamics of elevators is described by the piecewise map model combined with the circle map. The motion of the elevators depends on the inflow rate, its period, and the number of elevators. The motion in the piecewise map model combined with the circle map shows a complex behavior different from the motion in the piecewise map model.

  8. Discriminants and functional equations for polynomials orthogonal on the unit circle

    International Nuclear Information System (INIS)

    Ismail, M.E.H.; Witte, N.S.

    2000-01-01

    We derive raising and lowering operators for orthogonal polynomials on the unit circle and find second order differential and q-difference equations for these polynomials. A general functional equation is found which allows one to relate the zeros of the orthogonal polynomials to the stationary values of an explicit quasi-energy and implies recurrences on the orthogonal polynomial coefficients. We also evaluate the discriminants and quantized discriminants of polynomials orthogonal on the unit circle

  9. Multimodal determination of Rayleigh dispersion and attenuation curves using the circle fit method

    Science.gov (United States)

    Verachtert, R.; Lombaert, G.; Degrande, G.

    2018-03-01

    This paper introduces the circle fit method for the determination of multi-modal Rayleigh dispersion and attenuation curves as part of a Multichannel Analysis of Surface Waves (MASW) experiment. The wave field is transformed to the frequency-wavenumber (fk) domain using a discretized Hankel transform. In a Nyquist plot of the fk-spectrum, displaying the imaginary part against the real part, the Rayleigh wave modes correspond to circles. The experimental Rayleigh dispersion and attenuation curves are derived from the angular sweep of the central angle of these circles. The method can also be applied to the analytical fk-spectrum of the Green's function of a layered half-space in order to compute dispersion and attenuation curves, as an alternative to solving an eigenvalue problem. A MASW experiment is subsequently simulated for a site with a regular velocity profile and a site with a soft layer trapped between two stiffer layers. The performance of the circle fit method to determine the dispersion and attenuation curves is compared with the peak picking method and the half-power bandwidth method. The circle fit method is found to be the most accurate and robust method for the determination of the dispersion curves. When determining attenuation curves, the circle fit method and half-power bandwidth method are accurate if the mode exhibits a sharp peak in the fk-spectrum. Furthermore, simulated and theoretical attenuation curves determined with the circle fit method agree very well. A similar correspondence is not obtained when using the half-power bandwidth method. Finally, the circle fit method is applied to measurement data obtained for a MASW experiment at a site in Heverlee, Belgium. In order to validate the soil profile obtained from the inversion procedure, force-velocity transfer functions were computed and found in good correspondence with the experimental transfer functions, especially in the frequency range between 5 and 80 Hz.

  10. Pengaruh Penerapan Metode Socratic Circles Disertai Media Gambar Terhadap Kemampuan Berpikir Kreatif Siswa

    OpenAIRE

    Afidah, Ihda Nuria; Santosa, Slamet; Indrowati, Meti

    2012-01-01

    - This research aims to ascertain whether or not the application Socratic Circles method with images media affects the student's creative thinking skill.This research is considered quasi-experiment research. The research was designed using Posttest-Only Control Group Design by applying Socratic Circles method with images media in experimental group and lectures methods, discussions, and presentations in control group. The population of this research were all strudents in X grade of SMA Nege...

  11. Finite-element model to predict roll-separation force and defects during rolling of U-10Mo alloys

    Energy Technology Data Exchange (ETDEWEB)

    Soulami, Ayoub; Burkes, Douglas E.; Joshi, Vineet V.; Lavender, Curt A.; Paxton, Dean

    2017-10-01

    This study used a finite element code, LSDYNA, as a predictive tool to optimize the rolling process. Simulations of the hot rolling of U-10Mo coupons encapsulated in low-carbon steel were conducted following two different schedules. Model predictions of the roll-separation force and roll pack thicknesses at different stages of the rolling process were compared with experimental measurements. The study reported here discussed various attributes of the rolled coupons revealed by the model (e.g., waviness and thickness non-uniformity like dog boning). To investigate the influence of the cladding material on these rolling defects, other cases were simulated:  hot rolling with alternative can materials, namely, 304 stainless steel and Zircaloy-2, and bare-rolling.

  12. A Study of the Batch Annealing of Cold-Rolled HSLA Steels Containing Niobium or Titanium

    Science.gov (United States)

    Fang, Chao; Garcia, C. Isaac; Choi, Shi-Hoon; DeArdo, Anthony J.

    2015-08-01

    The batch annealing behavior of two cold-rolled, microalloyed HSLA steels has been studied in this program. One steel was microalloyed with niobium while the other with titanium. A successfully batch annealed steel will exhibit minimum variation in properties along the length of the coil, even though the inner and outer wraps experience faster heating and cooling rates and lower soaking temperatures, i.e., the so-called "cold spot" areas, than the mid-length portion of the coil, i.e., the so-called "hot spot" areas. The variation in strength and ductility is caused by differences in the extent of annealing in the different areas. It has been known for 30 years that titanium-bearing HSLA steels show more variability after batch annealing than do the niobium-bearing steels. One of the goals of this study was to try to explain this observation. In this study, the annealing kinetics of the surface and center layers of the cold-rolled sheet were compared. The surface and center layers of the niobium steel and the surface layer of the titanium steel all showed similar annealing kinetics, while the center layer of the titanium steel exhibited much slower kinetics. Metallographic results indicate that the stored energy of the cold-rolled condition, as revealed by grain center sub-grain boundary density, appeared to strongly influence the annealing kinetics. The kinetics were followed by the Kernel Average Misorientation reconstruction of the microstructure at different stages on annealing. Possible pinning effects caused by microalloy precipitates were also considered. Methods of improving uniformity and increasing kinetics, involving optimizing both hot-rolled and cold-rolled microstructure, are suggested.

  13. Safety, dose optimisation and security: the quadrature of the circle

    Energy Technology Data Exchange (ETDEWEB)

    Hardeman, Frank; Vermeersch, Fernand [Belgian Nuclear Research Centre (SCK.CEN), Boeretang 200, BE-2400 Mol (Belgium)

    2010-07-01

    The growing concern for potential terrorist acts has lead to a number of new ideas about storing radiological and nuclear materials that are not always compatible with existing practices or infrastructures. This is valid in routine circumstances, but especially poses problems in case of accidents. As such, the management of nuclear safety, radiological protection and security within an evolving world such as a nuclear research centre sometimes looks like implementing the quadrature of the circle. International guidance exists, but is not always easily converted into an adequate policy comprehensible to all levels in a plant, from management to the work floor. Some examples. 1. infrastructure related problems: from a security point of view, fuels are better stored in the heart of a protected zone, while in case of criticality, fire... a more peripheral location is appropriate. 2. Safety related problems: Protection infrastructure may lead to difficulties of evacuation in case of emergencies; access limitations may be a burden in the management of safety interventions, maintenance... 3. Administrative contradictions: inventories of fuel storages and high active sealed sources are a cornerstone of inspections and verifications; yet, this information is a treasure for terrorists aiming at actions to obtain special materials. 4. Dose management: measures taken to secure sources may lead to a dose increase (e.g. labelling of old sources). However, the main difficulty is related to the 'cultural' aspect. There are synergies between safety culture, 'ALARA' culture and security culture. An individual aspect of desirable behaviour (e.g. questioning attitude), complemented with an organisational dimension (e.g. training, raising awareness) are obviously common. The objective is also in line: to avoid reduction of well-being of people, to protect the environment, to prevent damage to facilities. The main difficulties arise however because of the fundamental

  14. Experimental study of hemodynamics in the Circle of Willis.

    Science.gov (United States)

    Zhu, Guangyu; Yuan, Qi; Yang, Jian; Yeo, Joon

    2015-01-01

    The Circle of Willis (CoW) is an important collateral pathway of the cerebral blood flow. An experimental study of the cerebral blood flow (CBF) distribution in different anatomical variations may help to a better understanding of the collateral mechanism of the CoW. An in-vitro test rig was developed to simulate the physiological cerebral blood flow in the CoW. Ten anatomical variations were considered in this study, include a set of different degrees of stenosis in L-ICA and L-ICA occlusion coexist with common anatomical variations. Volume flow rates of efferent arteries and pressure signals at the end of communicating arteries of each case were recorded. Physiological pressure waveforms were applied as inlet boundary condition. In the development of L-ICA stenosis, the total CBF decreases with the increase of stenosis degree. The blood supply of ipsilateral middle cerebral artery (MCA) was affected most by the stenosis of L-ICA. Anterior communicating artery (ACoA) and ipsilateral posterior communicating artery (PCoA) function as important collateral pathways of cerebral collateral circulation when unilateral stenosis occurred. The blood supply of anterior cerebral circulation was compensated by the posterior cerebral circulation through ipsilateral PCoA when L-ICA stenosis degree is greater than 40% and the affected side was compensated immediately by the unaffected side through ACoA. Blood flow of the anterior circulation and the total CBF reached the minimum among all cases studied when L-ICA occlusion coexist with the absence of PCoA. The results demonstrated the flow distribution patterns of the CoW under anatomical variations and clarified the collateral mechanism of the CoW. The flow ACoA is the most sensitive indexes to the morphology change of ipsilateral ICA. The relative independence of the circulation in anterior and posterior sections of the CoW is not broken and the function of ipsilateral PCoA is not activated until a severe stenosis of unilateral

  15. Safety, dose optimisation and security: the quadrature of the circle

    International Nuclear Information System (INIS)

    Hardeman, Frank; Vermeersch, Fernand

    2010-01-01

    The growing concern for potential terrorist acts has lead to a number of new ideas about storing radiological and nuclear materials that are not always compatible with existing practices or infrastructures. This is valid in routine circumstances, but especially poses problems in case of accidents. As such, the management of nuclear safety, radiological protection and security within an evolving world such as a nuclear research centre sometimes looks like implementing the quadrature of the circle. International guidance exists, but is not always easily converted into an adequate policy comprehensible to all levels in a plant, from management to the work floor. Some examples. 1. infrastructure related problems: from a security point of view, fuels are better stored in the heart of a protected zone, while in case of criticality, fire... a more peripheral location is appropriate. 2. Safety related problems: Protection infrastructure may lead to difficulties of evacuation in case of emergencies; access limitations may be a burden in the management of safety interventions, maintenance... 3. Administrative contradictions: inventories of fuel storages and high active sealed sources are a cornerstone of inspections and verifications; yet, this information is a treasure for terrorists aiming at actions to obtain special materials. 4. Dose management: measures taken to secure sources may lead to a dose increase (e.g. labelling of old sources). However, the main difficulty is related to the 'cultural' aspect. There are synergies between safety culture, 'ALARA' culture and security culture. An individual aspect of desirable behaviour (e.g. questioning attitude), complemented with an organisational dimension (e.g. training, raising awareness) are obviously common. The objective is also in line: to avoid reduction of well-being of people, to protect the environment, to prevent damage to facilities. The main difficulties arise however because of the fundamental differences being

  16. 75 FR 77828 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Extension of Time Limit...

    Science.gov (United States)

    2010-12-14

    ...-Rolled Carbon-Quality Steel Products From Brazil: Extension of Time Limit for Final Results of...-Rolled Carbon Quality Steel Products From Brazil: Preliminary Results of Countervailing Duty... administrative review of the countervailing duty order on certain hot-rolled flat-rolled carbon- quality steel...

  17. Truck Roll Stability Data Collection and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, SS

    2001-07-02

    The principal objective of this project was to collect and analyze vehicle and highway data that are relevant to the problem of truck rollover crashes, and in particular to the subset of rollover crashes that are caused by the driver error of entering a curve at a speed too great to allow safe completion of the turn. The data are of two sorts--vehicle dynamic performance data, and highway geometry data as revealed by vehicle behavior in normal driving. Vehicle dynamic performance data are relevant because the roll stability of a tractor trailer depends both on inherent physical characteristics of the vehicle and on the weight and distribution of the particular cargo that is being carried. Highway geometric data are relevant because the set of crashes of primary interest to this study are caused by lateral acceleration demand in a curve that exceeds the instantaneous roll stability of the vehicle. An analysis of data quality requires an evaluation of the equipment used to collect the data because the reliability and accuracy of both the equipment and the data could profoundly affect the safety of the driver and other highway users. Therefore, a concomitant objective was an evaluation of the performance of the set of data-collection equipment on the truck and trailer. The objective concerning evaluation of the equipment was accomplished, but the results were not entirely positive. Significant engineering apparently remains to be done before a reliable system can be fielded. Problems were identified with the trailer to tractor fiber optic connector used for this test. In an over-the-road environment, the communication between the trailer instrumentation and the tractor must be dependable. In addition, the computer in the truck must be able to withstand the rigors of the road. The major objective--data collection and analysis--was also accomplished. Using data collected by instruments on the truck, a ''bad-curve'' database can be generated. Using

  18. Conceptualizing Rolling Motion through an Extreme Case Reasoning Approach

    Science.gov (United States)

    Hasovic, Elvedin; Mešic, Vanes; Erceg, Nataša

    2017-01-01

    In this paper we are going to show how learning about some counterintuitive aspects of rolling motion can be facilitated by combining the use of analogies with extreme case reasoning. Specifically, the intuitively comprehensible examples of "rolling" polygonal prisms are used as an analogical anchor that is supposed to help the students…

  19. Hot-rolling metals in vacuum. Information circular

    International Nuclear Information System (INIS)

    Beall, R.A.; Worthington, R.B.; Blickensderfer, R.

    1979-01-01

    The process of hot-rolling metals, alloys, and composites in vacuum is studied. First, a comprehensive review of the literature is presented, including the advantages and disadvantages of using vacuum. Next, details of hot-rolling titanium, chromium, and molybdenum-iron bimetal are given. Finally, the design of new equipment is described

  20. Disruption Management of Rolling Stock in Passenger Railway Transportation

    NARCIS (Netherlands)

    L.K. Nielsen (Lars Kjaer); G. Maróti (Gábor)

    2009-01-01

    textabstractThis paper deals with real-time disruption management of rolling stock in passenger railway transportation. We present a generic framework for modeling disruptions in railway rolling stock schedules. The framework is presented as an online combinatorial decision problem where the

  1. Photosynthetic characterization of a rolled leaf mutant of rice ( Oryza ...

    African Journals Online (AJOL)

    A new rolling leaf rice mutant was identified which showed an apparently straighter longitudinal shape normal transverse rolling characters at all developing stages. The chlorophyll contents per fresh weight of this mutant leaves were lower than those of wild-type. The electron transfer rate (ETR) and photochemical ...

  2. Estimation of Parametric Roll in a Stochastic Seaway

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Pedersen, Preben Terndrup; Vidic-Perunovic, Jelena

    2008-01-01

    -degree of freedom (roll and heave) time domain model [10]. In the present paper the effect of the increased added resistance when the bow heaves and pitches down in a wave crest is introduced. Due to the resulting forward speed variation the roll resonance condition will be changed. The influence of ship speed...

  3. Study of Hydroplaning Risk on Rolling and Sliding Passenger Car

    NARCIS (Netherlands)

    Kumar, S.S.; Anupam, K.; Scarpas, A.; Kasbergen, C.

    2012-01-01

    Hydroplaning speed is known to vary over a range of tire slipping conditions from free rolling to completely skidding. An attempt has been made to simulate two extreme conditions of hydroplaning i.e. when the tire is completely rolling (0% slip) and a completely locked tire (100% slip). ASTM

  4. Determination of residual stresses in roll compacted titanium strips

    CSIR Research Space (South Africa)

    Mothosi, KL

    2017-01-01

    Full Text Available residual stresses using x-ray diffraction (XRD) surface probing technique. Preliminary results were obtained for the surface residual stress at the center of the titanium strips for the 100 and 325 mesh strips rolled at 0.1 roll gap for 20 and 50 mm set...

  5. 14 CFR 25.493 - Braked roll conditions.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Braked roll conditions. 25.493 Section 25.493 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.493 Braked roll conditions. (a...

  6. Anatomical variations of the circle of Willis and cerebrovascular accidents in transitional Albania

    Directory of Open Access Journals (Sweden)

    Edlira Harizi (Shemsi

    2015-12-01

    Full Text Available Aim: The purpose of this study was twofold: i in a case-control design, to determine the relationship between anatomical variations of the circle of Willis and cerebrovascular accidents; ii to assess the association between anatomical variations of the circle of Willis and aneurisms among patients with subarachnoid hemorrhage. Methods: A case-control study was conducted in Albania in 2013-2014, including 100 patients with subarachnoid hemorrhage and 100 controls (individuals without cerebrovascular accidents. Patients with subarachnoid hemorrhage underwent a CT angiography procedure, whereas individuals in the control group underwent a magnetic resonance angiography procedure. Binary logistic regression was used to assess the association between cerebrovascular accidents and the anatomical variations of the circle of Willis. Conversely, Fisher’s exact test was used to compare the prevalence of aneurisms between subarachnoid hemorrhage patients with and without anatomical variations of the circle of Willis. Results: Among patients, there were 22 (22% cases with anatomical variations of the circle of Willis compared with 10 (10% individuals in the control group (P=0.033. There was no evidence of a statistically significant difference in the types of the anatomical variations of the circle of Willis between patients and controls (P=0.402. In age- and-sex adjusted logistic regression models, there was evidence of a significant positive association between cerebrovascular accidents and the anatomical variations of the circle of Willis (OR=1.87, 95%CI=1.03-4.68, P=0.048. Within the patients’ group, of the 52 cases with aneurisms, there were 22 (42.3% individuals with anatomical variations of the circle of Willis compared with no individuals with anatomical variations among the 48 patients without aneurisms (P<0.001. Conclusion: This study provides useful evidence on the association between anatomical variations of the circle of Willis and

  7. Measurement by a cylinder test stand and tyre rolling resistance

    Directory of Open Access Journals (Sweden)

    A. Dávid

    2006-03-01

    Full Text Available Sometimes it is necessary to test how repair affects the properties of the car. These tests are carried out using a cylinder test stand. During the test the tyre is rolling between two cylinders of a small diameter. The question arises whether the rolling resistance of the tyre is the same as the rolling resistance when the wheel is rolling on the plane. If it is not the same what is the reliation between tyre resistances in these two cases? It is an important answer because the change of rolling resistance can affect consumption, the highest speed, engine power and other results of measurement. The paper gives the answer to these questions and describes the method of getting this information.

  8. Diagnostic capability of 100-mm roll film digitizer system

    International Nuclear Information System (INIS)

    Kono, M.; Yamasaki, K.; Ikeda, M.

    1988-01-01

    The authors recently developed a roll film digitizer system. The sampling pitch is 100 μm. a scientific image study (Barger phantom, Hawlet chart, and modulation transfer function), receiver operating characteristic (ROC) study, and clinical evaluation were performed. For the ROC study, a chest phantom with simulated nodule and hairline was used. Differences in accuracy between readings of cathode ray tube (CRT) images and roll film images were not statistically significant for hairline and coin lesions, P<.05). As a clinical evaluation, eight radiologists evaluated predetermined radiologic findings on a five-point rating scale compared with original roll film images. Scores for CRT images were equal to those for the original roll film images. In conclusion, CRT images (1,000 x 1,000) were found to be sufficient for diagnostic accuracy of chest images compared with roll film images (100 x 100 mm)

  9. Spring-back of flexible roll forming bending process

    International Nuclear Information System (INIS)

    Zhang, Y; Kim, D H; Jung, D W

    2015-01-01

    Simulations are now widely used in the field of roll forming because of their convenience. Simulations provide a low cost, secure and fast analysis tool. Flexible roll forming provides the desired shapes with a one time forming process. For roll forming, the velocity of the sheet and friction are important factors to attain an ideal shape. Because it is a complicated process, simulations provide a better understanding of the roll forming process. Simulations were peformed using ABAQUS software linked to elastic-plastic modules which we developed taking into account of interactions between these fields [1]. The application of this method makes it possible to highlight the strain-stress and mechanical behaviour laws and the spring-back. Thus, the flexible roll forming and bending process can be well described by the simulation software and guide the actual machine. (paper)

  10. Parametric roll resonance monitoring using signal-based detection

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Blanke, Mogens; Falkenberg, Thomas

    2015-01-01

    Extreme roll motion of ships can be caused by several phenomena, one of which is parametric roll resonance. Several incidents occurred unexpectedly around the millennium and caused vast fiscal losses on large container vessels. The phenomenon is now well understood and some consider parametric roll...... algorithms in real conditions, and to evaluate the frequency of parametric roll events on the selected vessels. Detection performance is scrutinised through the validation of the detected events using owners’ standard methods, and supported by available wave radar data. Further, a bivariate statistical...... analysis of the outcome of the signal-based detectors is performed to assess the real life false alarm probability. It is shown that detection robustness and very low false warning rates are obtained. The study concludes that small parametric roll events are occurring, and that the proposed signal...

  11. Rolling motions in an inner spiral arm

    International Nuclear Information System (INIS)

    Strauss, F.M.; Poeppel, W.

    1976-01-01

    Hydrogen line observations made at low galactic latitudes for l=318degree, 326degree, 334degree, and 337degree show the presence of velocity gradients in latitude in the nearest inner spiral arm, similar to those found by other observations in different regions. Maximum velocity change is about 10 km s -1 for l=337degree. By generating synthetic line profiles constructed from a model spiral arm, several possible causes of these ''rolling motions'' were studied, such as a vertical displacement or a tilt of the arm (which failed to account for the observations) and rotation or shearing in the arm. It was futher shown that a typical arm can maintain such a motion (approx. =75 km s -1 kpc -1 ) with its own gravitational potential. The results are used to study the origin and tilt of Gould's Belt

  12. Annealing texture of rolled nickel alloys

    International Nuclear Information System (INIS)

    Meshchaninov, I.V.; Khayutin, S.G.

    1976-01-01

    A texture of pure nickel and binary alloys after the 95% rolling and annealing has been studied. Insoluble additives (Mg, Zr) slacken the cubic texture in nickel and neral slackening of the texture (Zr). In the case of alloying with silicium (up to 2%) the texture practically coinsides with that of a technical-grade nickel. The remaining soluble additives either do not change the texture of pure nickel (C, Nb) or enhance the sharpness and intensity of the cubic compontnt (Al, Cu, Mn, Cr, Mo, W, Co -at their content 0.5 to 2.0%). A model is proposed by which variation of the annealing texture upon alloying is caused by dissimilar effect of the alloying elements on the mobility of high- and low-angle grain boundaries

  13. Low Band Gap Polymers for Roll-to-Roll Coated Polymer Solar Cells

    DEFF Research Database (Denmark)

    Bundgaard, Eva; Hagemann, Ole; Manceau, Matthieu

    2010-01-01

    connected cells were prepared with a total module active area of 96 cm2. The devices were tested for operational stability under simulated sunlight (AM1.5G) and natural sunlight, and the photochemical stability of the polymer was examined using a combination of UV−vis and IR spectroscopy.......We present the synthesis of a low band gap copolymer based on dithienothiophene and dialkoxybenzothiadiazole (poly(dithienothiophene-co-dialkoxybenzothiadiazole), PDTTDABT). The optical properties of the polymer showed a band gap of 1.6 eV and a sky-blue color in solid films. The polymer...... around a 1:2 mixing ratio. Roll-to-roll coated polymer solar cell devices were prepared under ambient conditions employing solution processing in all steps including the metallic back electrode that was printed as a grid giving semitransparent solar cell devices. Solar cell modules comprising 16 serially...

  14. Roll-to-roll production of spray coated N-doped carbon nanotube electrodes for supercapacitors

    Science.gov (United States)

    Karakaya, Mehmet; Zhu, Jingyi; Raghavendra, Achyut J.; Podila, Ramakrishna; Parler, Samuel G.; Kaplan, James P.; Rao, Apparao M.

    2014-12-01

    Although carbon nanomaterials are being increasingly used in energy storage, there has been a lack of inexpensive, continuous, and scalable synthesis methods. Here, we present a scalable roll-to-roll (R2R) spray coating process for synthesizing randomly oriented multi-walled carbon nanotubes electrodes on Al foils. The coin and jellyroll type supercapacitors comprised such electrodes yield high power densities (˜700 mW/cm3) and energy densities (1 mW h/cm3) on par with Li-ion thin film batteries. These devices exhibit excellent cycle stability with no loss in performance over more than a thousand cycles. Our cost analysis shows that the R2R spray coating process can produce supercapacitors with 10 times the energy density of conventional activated carbon devices at ˜17% lower cost.

  15. Development of polymers for large scale roll-to-roll processing of polymer solar cells

    DEFF Research Database (Denmark)

    Carlé, Jon Eggert

    Development of polymers for large scale roll-to-roll processing of polymer solar cells Conjugated polymers potential to both absorb light and transport current as well as the perspective of low cost and large scale production has made these kinds of material attractive in solar cell research....... The research field of polymer solar cells (PSCs) is rapidly progressing along three lines: Improvement of efficiency and stability together with the introduction of large scale production methods. All three lines are explored in this work. The thesis describes low band gap polymers and why these are needed....... Polymer of this type display broader absorption resulting in better overlap with the solar spectrum and potentially higher current density. Synthesis, characterization and device performance of three series of polymers illustrating how the absorption spectrum of polymers can be manipulated synthetically...

  16. Roll-to-roll printed resistive WORM memory on a flexible substrate

    International Nuclear Information System (INIS)

    Leppäniemi, Jaakko; Mattila, Tomi; Suhonen, Mika; Alastalo, Ari; Kololuoma, Terho

    2012-01-01

    The fabrication process and the operation characteristics of a fully roll-to-roll printed resistive write-once-read-many memory on a flexible substrate are presented. The low-voltage (<10 V) write operation of the memories from a high resistivity ‘0’ state to a low resistivity ‘1’ state is based on the rapid electrical sintering of bits containing silver nanoparticles. The bit ink is formulated by mixing two commercially available silver nanoparticle inks in order to tune the initial square resistance of the bits and to create a self-organized network of percolating paths. The electrical performance of the memories, including read and write characteristics, is described and the long-term stability of the less stable ‘0’ state is studied in different environmental conditions. The memories can find use in low-cost mass printing applications. (paper)

  17. Roll-to-roll printed resistive WORM memory on a flexible substrate

    Science.gov (United States)

    Leppäniemi, Jaakko; Mattila, Tomi; Kololuoma, Terho; Suhonen, Mika; Alastalo, Ari

    2012-08-01

    The fabrication process and the operation characteristics of a fully roll-to-roll printed resistive write-once-read-many memory on a flexible substrate are presented. The low-voltage (memories from a high resistivity ‘0’ state to a low resistivity ‘1’ state is based on the rapid electrical sintering of bits containing silver nanoparticles. The bit ink is formulated by mixing two commercially available silver nanoparticle inks in order to tune the initial square resistance of the bits and to create a self-organized network of percolating paths. The electrical performance of the memories, including read and write characteristics, is described and the long-term stability of the less stable ‘0’ state is studied in different environmental conditions. The memories can find use in low-cost mass printing applications.

  18. Roll-to-Roll Manufacturing of Robust Superhydrophobic Coating on Metallic Engineering Materials.

    Science.gov (United States)

    Dong, Shuliang; Wang, Zhenlong; Wang, Yukui; Bai, Xuelin; Fu, Yong Qing; Guo, Bin; Tan, Chaoliang; Zhang, Jia; Hu, PingAn

    2018-01-17

    Creating a robust superhydrophobic surface on the conventional engineering materials at mass production is of great importance for a self-cleaning, anti-icing, nonwetting surface and low flow resistance in industrial applications. Herein, we report a roll-to-roll strategy to create durable and robust superhydrophobic surfaces with designed micro-/nanoscale hierarchical structures on many conventional engineering materials by combining electrical discharge machining and coating of carbon nanoparticles, followed by oil penetration and drying. The treated surface shows good superhydrophobic properties with a static water contact angle of 170 ± 2° and slide angle of 3 ± 1°. The treated surface also exhibits good resilience and maintains the performance after being tested in various harsh conditions, including water flushing for several days, sand abrasion, scratching with sandpapers, and corrosive solution. Significantly, the superhydrophobic surfaces also show a high efficiency of self-cleaning properties even after oil contamination during applications.

  19. Roll-to-Roll Fabricated Polymer Solar Cells: Towards Low Environmental Impact and Reporting Consensus

    DEFF Research Database (Denmark)

    Larsen-Olsen, Thue Trofod

    The sun is by far the largest source of renewable energy available; consequently solar cells, which are able to convert light into electricity, have the technical potential to cover the global energy needs. Polymer solar cells (PSCs) on flexible plastic substrate have a low embodied energy and can...... be processed by fast roll-to-roll (R2R) methods, using earth abundant materials, and thus deliver the prospects to fulfil this potential. A strong polarization in PSC research efforts have led to diverging and non-comparable results: While very high power conversion efficiencies (PCEs) above 10% have been......, through R2R processing of tandem PSCs. A final focus area of the thesis is the investigation into the extrinsic variability in standard J-V characterizations done on PSCs, and towards ways to minimize it. Organic solvents are predominant process solvents used for fabricating the active layer of a PSC...

  20. Advanced cold rolled steels for automotive applications

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, H. [ThyssenKrupp Steel AG, Eberhardstrasse 12, 44145 Dortmund (Germany); Mattissen, D.; Schaumann, T.W. [ThyssenKrupp Steel AG, Duisburg (Germany)

    2006-09-15

    Advanced multiphase steels offer a great potential for bodies-in-white through their combination of formability and achievable component strength levels. They are first choice for strength and crash-relevant parts of challenging geometry. The intensive development of high-strength multiphase steels by ThyssenKrupp has led to hot dip galvanizing concepts with an outstanding forming potential. Hot rolled, hot dip galvanized complex phase steels are currently produced in addition to cold rolled DP and RA steels. New continuously annealed grades with tensile strength levels of up to 1000 MPa in combination with sufficient ductility for applications mainly in the field of structural automobile elements make use of the classic advantages of microalloying as well as the principles of DP and TRIP steels. Further improvement of properties will be reached by the new class of high manganese alloyed steels. (Abstract Copyright [2006], Wiley Periodicals, Inc.) [German] Fortschrittliche Multiphasen-Staehle eroeffnen wegen der inzwischen erreichbaren Kombination aus Umformbarkeit und Bauteilfestigkeit ein enormes Potenzial fuer Rohkarosserien. Sie stellen eine erste Wahl dar, wenn es um Festigkeit und um Crashsicherheit geht und besondere Anforderungen an die Bauteilgeometrien gestellt werden. Bei ThyssenKrupp hat die Entwicklung hochfester Multiphasen-Staehle in Verbindung mit dem Feuerverzinken zur Realisierung von Blechhalbzeugen gefuehrt, die hervorragend formbar sind. Es werden heute feuerverzinkte Komplexphasenstaehle neben den bewaehrten kaltgewalzten Dualphasen(DP) - und Retained Austenit(RA)-Staehlen produziert. Die neuen kontinuierlich gegluehten Stahlvarianten mit Festigkeiten bis zu 1000 MPa in Kombination mit der bei Strukturbauteilen im Automobilbau geforderten Duktilitaet nutzen sowohl die klassischen Vorteile des Mikrolegierens aus und dazu die Prinzipien, die man bei DP- und TRIP-Staehlen anwendet. Eine weitere Verbesserung des Eigenschaftsprofils wird mit dem