Sample records for net confining stress

  1. Wild trout responses to a stress experience following confinement conditions during the spawning season

    Directory of Open Access Journals (Sweden)

    Gilberto Forneris


    Full Text Available Salmo (trutta marmoratus is an endemic specie in the North of Italy, subjected to hybridization with domesticated strains of trout. Native populations are managed by supportive release in the rivers. Wild breeders are captured, confined in facility for short periods and then released in the river after artificial fertilization. Premature mortality during confinement and post release mortality in river have been observed in breeders supporting the view that confinement stress could be the cause. Twenty-six adult individuals of trout were captured from a river by electrofishing and stocked in two tanks, the first one (RF provided with artificial refuges to simulate the natural environment and covered by dark panels; the second tank (TR was only partially covered by dark panels and without artificial refuges. All the other conditions were identical and animals were fed ad libitum with natural food collected in the same river. After 50 days, from a third group of 8 trout (WD captured in the same river by a 5 minute electrofishing session, blood samples were sequentially collected for the assessment of serum cortisol response to serial repeated handlings. With the same sequential method, individuals of the RF and TR experimental groups were sampled. Cortisol levels were compared between groups by ANOVA. Biomass densities decreased during the experiment due to premature mortality of the largest individuals in both the RF (7.69% and TR (30.77% groups. At the end of the experiment, data clearly demonstrated that after a stressing confinement, the TR group shown a reduced poststress response to the successive serial handlings. Vice versa the group RF, that experienced a more careful confinement, responded to the second serial acute stressing manipulation in conformity as the group WD that was not confined. Cortisol data support the hypothesis of impaired cortisol response as a consequence of oversecretion due to uneasiness during the short

  2. Theoretical Studies of Stress Wave Propagation in Laterally Confined Soils

    National Research Council Canada - National Science Library

    Rohani, Behzad


    .... A considerable body of scientific literature on one-dimensional stress wave propagation for such models has been published in recent years by various researchers, both in the United States and abroad...

  3. A novel method for estimating soil precompression stress from uniaxial confined compression tests

    DEFF Research Database (Denmark)

    Lamandé, Mathieu; Schjønning, Per; Labouriau, Rodrigo


    obtained from the new method were linearly related to the maximum stress experienced by the soil samples prior to the uniaxial, confined compression test at each soil condition with a slope close to 1. Precompression stress determined with the new method was not related to soil type or dry bulk density......The concept of precompression stress is used for estimating soil strength of relevance to fieldtraffic. It represents the maximum stress experienced by the soil. The most recently developed fitting method to estimate precompression stress (Gompertz) is based on the assumption of an S-shape stress......-strain curve, which is not always fulfilled. A new simple numerical method was developed to estimate precompression stress from stress-strain curves, based solely on the sharp bend on the stress-strain curve partitioning the curve into an elastic and a plastic section. Our study had three objectives: (i...

  4. Spline Nonparametric Regression Analysis of Stress-Strain Curve of Confined Concrete

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    Tavio Tavio


    Full Text Available Due to enormous uncertainties in confinement models associated with the maximum compressive strength and ductility of concrete confined by rectilinear ties, the implementation of spline nonparametric regression analysis is proposed herein as an alternative approach. The statistical evaluation is carried out based on 128 large-scale column specimens of either normal-or high-strength concrete tested under uniaxial compression. The main advantage of this kind of analysis is that it can be applied when the trend of relation between predictor and response variables are not obvious. The error in the analysis can, therefore, be minimized so that it does not depend on the assumption of a particular shape of the curve. This provides higher flexibility in the application. The results of the statistical analysis indicates that the stress-strain curves of confined concrete obtained from the spline nonparametric regression analysis proves to be in good agreement with the experimental curves available in literatures

  5. How thermal stress alters the confinement of polymers vitrificated in nanopores (United States)

    Teng, Chao; Li, Linling; Wang, Yong; Wang, Rong; Chen, Wei; Wang, Xiaoliang; Xue, Gi


    Understanding and controlling the glass transition temperature (Tg) and dynamics of polymers in confined geometries are of significance in both academia and industry. Here, we investigate how the thermal stress induced by a mismatch in the coefficient of thermal expansion affects the Tg behavior of polystyrene (PS) nanorods located inside cylindrical alumina nanopores. The size effects and molecular weight dependence of the Tg are also studied. A multi-step relaxation process was employed to study the relationship between thermal stress and cooling rate. At fast cooling rates, the imparted thermal stress would overcome the yield stress of PS and peel chains off the pore walls, while at slow cooling rates, chains are kept in contact with the pore walls due to timely dissipation of the produced thermal stress during vitrification. In smaller nanopores, more PS chains closely contact with pore walls, then stronger internal thermal stress would be generated between core and shell of PS nanorod, which results in a larger deviation between two Tgs. The core part of PS shows lower Tg than bulk value, which can induce faster dynamics in the center region. A complex and important role stress plays is supposed in complex confinement condition, e.g., in nanopores, during vitrification.

  6. RNA-seq analysis of early hepatic response to handling and confinement stress in rainbow trout.

    Directory of Open Access Journals (Sweden)

    Sixin Liu

    Full Text Available Fish under intensive rearing conditions experience various stressors which have negative impacts on survival, growth, reproduction and fillet quality. Identifying and characterizing the molecular mechanisms underlying stress responses will facilitate the development of strategies that aim to improve animal welfare and aquaculture production efficiency. In this study, we used RNA-seq to identify transcripts which are differentially expressed in the rainbow trout liver in response to handling and confinement stress. These stressors were selected due to their relevance in aquaculture production. Total RNA was extracted from the livers of individual fish in five tanks having eight fish each, including three tanks of fish subjected to a 3 hour handling and confinement stress and two control tanks. Equal amount of total RNA of six individual fish was pooled by tank to create five RNA-seq libraries which were sequenced in one lane of Illumina HiSeq 2000. Three sequencing runs were conducted to obtain a total of 491,570,566 reads which were mapped onto the previously generated stress reference transcriptome to identify 316 differentially expressed transcripts (DETs. Twenty one DETs were selected for qPCR to validate the RNA-seq approach. The fold changes in gene expression identified by RNA-seq and qPCR were highly correlated (R(2 = 0.88. Several gene ontology terms including transcription factor activity and biological process such as glucose metabolic process were enriched among these DETs. Pathways involved in response to handling and confinement stress were implicated by mapping the DETs to reference pathways in the KEGG database.Raw RNA-seq reads have been submitted to the NCBI Short Read Archive under accession number SRP022881.All customized scripts described in this paper are available from Dr. Guangtu Gao or the corresponding author.

  7. Predicting Nonlinear Behavior and Stress-Strain Relationship of Rectangular Confined Reinforced Concrete Columns with ANSYS

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    A. Tata


    Full Text Available This paper presents a nonlinear finite element modeling and analysis of rectangular normal-strength reinforced concrete columns confined with transverse steel under axial compressive loading. In this study, the columns were modeled as discrete elements using ANSYS nonlinear finite element software. Concrete was modeled with 8-noded SOLID65 elements that can translate either in the x-, y-, or z-axis directions from ANSYS element library. Longitudinal and transverse steels were modeled as discrete elements using 3D-LINK8 bar elements available in the ANSYS element library. The nonlinear constitutive law of each material was also implemented in the model. The results indicate that the stress-strain relationships obtained from the analytical model using ANSYS are in good agreement with the experimental data. This has been confirmed with the insignificant difference between the analytical and experimental, i.e. 5.65 and 2.80 percent for the peak stress and the strain at the peak stress, respectively. The comparison shows that the ANSYS nonlinear finite element program is capable of modeling and predicting the actual nonlinear behavior of confined concrete column under axial loading. The actual stress-strain relationship, the strength gain and ductility improvement have also been confirmed to be satisfactorily.

  8. Whole-body cortisol response of zebrafish to acute net handling stress (United States)

    Ramsay, J.M.; Feist, G.W.; Varga, Z.M.; Westerfield, M.; Kent, M.L.; Schreck, C.B.


    Zebrafish, Danio rerio, are frequently handled during husbandry and experimental procedures in the laboratory, yet little is known about the physiological responses to such stressors. We measured the whole-body cortisol levels of adult zebrafish subjected to net stress and air exposure at intervals over a 24 h period; cortisol recovered to near control levels by about 1 h post-net-stress (PNS). We then measured cortisol at frequent intervals over a 1 h period. Cortisol levels were more than 2-fold higher in net stressed fish at 3 min PNS and continued to increase peaking at 15 min PNS, when cortisol levels were 6-fold greater than the control cortisol. Mean cortisol declined from 15 to 60 min PNS, and at 60 min, net-stressed cortisol was similar to control cortisol. Because the age of fish differed between studies, we examined resting cortisol levels of fish of different ages (3, 7, 13, and 19 months). The resting cortisol values among tanks with the same age fish differed significantly but there was no clear effect of age. Our study is the first to report the response and recovery of cortisol after net handling for laboratory-reared zebrafish. ?? 2009 Elsevier B.V.

  9. A sphingolipid-dependent diffusion barrier confines ER stress to the yeast mother cell (United States)

    Clay, Lori; Caudron, Fabrice; Denoth-Lippuner, Annina; Boettcher, Barbara; Buvelot Frei, Stéphanie; Snapp, Erik Lee; Barral, Yves


    In many cell types, lateral diffusion barriers compartmentalize the plasma membrane and, at least in budding yeast, the endoplasmic reticulum (ER). However, the molecular nature of these barriers, their mode of action and their cellular functions are unclear. Here, we show that misfolded proteins of the ER remain confined into the mother compartment of budding yeast cells. Confinement required the formation of a lateral diffusion barrier in the form of a distinct domain of the ER-membrane at the bud neck, in a septin-, Bud1 GTPase- and sphingolipid-dependent manner. The sphingolipids, but not Bud1, also contributed to barrier formation in the outer membrane of the dividing nucleus. Barrier-dependent confinement of ER stress into the mother cell promoted aging. Together, our data clarify the physical nature of lateral diffusion barriers in the ER and establish the role of such barriers in the asymmetric segregation of proteotoxic misfolded proteins during cell division and aging. DOI: PMID:24843009

  10. Liquefaction Mitigation Using Lateral Confinement Technique

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    W. R. Azzam


    Full Text Available The exploration of a series of shaking tests on circular model footing with and without cellular confinement constructed around the footing with variable depths and diameters under the effect of variable net bearing stress is studied. The effect of the confinement on the liquefaction time, final settlement, excess pore water pressure, and induced building acceleration were studied. The consequences showed that installing the cell with minimum diameter closer to footing and sufficient penetration depth significantly delayed the liquefaction time. It can be considered as an alternative technique to decrease both the lateral spreading and the final settlement below the foundation during the shaking. The results demonstrated that the cell reduced the excess pore water pressure within the confined zone and the pore water pressure migration outside the confined block where the liquefaction is induced. Moreover, the peak foundation acceleration of the confined footing soil system is reduced compared with the case of without cell confinement.

  11. Effect of confinement and starvation on stress parameters in the American lobster (Homarus americanus

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    Edo D'Agaro


    Full Text Available The American lobster (Homarus americanus is one of the most important crustacean resources in North America. In Italy and Europe, this fishery product is available throughout the year and it has a high and increasing commercial demand. American lobsters are traditionally marketed live and stocked, without feed, in temperature controlled recirculating systems for several weeks before being sold in the market places. The current Italian legislation does not fix a maximum length of time for the crustacean confinement and specific welfare requirements. In the present research, a 4-week experiment was carried out using 42 adult H. americanus reared in 4 recirculating aquaculture tanks. After one month of confinement, mean glucose, protein and total haemocyte count levels in the hemolymph of H. americanus were stable and similar (P>0.05 to the values observed at the beginning of the experiment. Results of the proximate analysis of the abdominal muscles of H. americanus showed no significant differences in concentrations of crude protein, lipid and ash during the trial. At the end of the experiment, the sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting analysis revealed a marked degradation of the muscle myofibrillar proteins. A number of fragments, possibly from myosin, were evident in the range between 50 and 220 kDa between time t0 and t28. Results of this study show that the main hemolymphatic variables and degradation analysis of the muscle myofibrillar proteins can be used as sensitive indicators of the crustacean stress response to confinement and starvation.

  12. Elastic stress transmission and transformation (ESTT) by confined liquid: A new mechanics for fracture in elastic lithosphere of the earth (United States)

    Xu, Xing-Wang; Peters, Stephen; Liang, Guang-He; Zhang, Bao-Lin


    We report on a new mechanical principle, which suggests that a confined liquid in the elastic lithosphere has the potential to transmit a maximum applied compressive stress. This stress can be transmitted to the internal contacts between rock and liquid and would then be transformed into a normal compressive stress with tangential tensile stress components. During this process, both effective compressive normal stress and tensile tangential stresses arise along the liquid–rock contact. The minimum effective tensile tangential stress causes the surrounding rock to rupture. Liquid-driven fracture initiates at the point along the rock–liquid boundary where the maximum compressive stress is applied and propagates along a plane that is perpendicular to the minimum effective tensile tangential stress and also is perpendicular to the minimum principal stress.

  13. Evaluation of Narrative Exposure Therapy (NET) for Borderline Personality Disorder with Comorbid Posttraumatic Stress Disorder


    Pabst, Astrid; Schauer, Maggie; Bernhardt, Kristin; Ruf-Leuschner, Martina; Goder, Robert; Elbert, Thomas; Rosentreager, Rotraudt; Robjant, Katy; Aldenhoff, Josef; Seeck-Hirschner, Mareen


    Objective: frequently patients with borderline personality disorder (BPD) report a history of exposure to traumatic stressors and, as a consequence, symptoms of Posttraumatic Stress Disorder (PTSD). BPD and PTSD combined exacerbate suffering beyond a simple additive effect. To assist these complex cases, we have tested the efficacy of Narrative Exposure Therapy (NET), an evidence-based treatment for survivors of different, multiple or continued traumatic stressors and compared the outcome wit...

  14. History of Solitary Confinement Is Associated with Post-Traumatic Stress Disorder Symptoms among Individuals Recently Released from Prison. (United States)

    Hagan, Brian O; Wang, Emily A; Aminawung, Jenerius A; Albizu-Garcia, Carmen E; Zaller, Nickolas; Nyamu, Sylviah; Shavit, Shira; Deluca, Joseph; Fox, Aaron D


    This study assessed the relationship between solitary confinement and post-traumatic stress disorder (PTSD) symptoms in a cohort of recently released former prisoners. The cross-sectional design utilized baseline data from the Transitions Clinic Network, a multi-site prospective longitudinal cohort study of post-incarceration medical care. Our main independent variable was self-reported solitary confinement during the participants' most recent incarceration; the dependent variable was the presence of PTSD symptoms determined by primary care (PC)-PTSD screening when participants initiated primary care in the community. We used multivariable logistic regression to adjust for potential confounders, such as prior mental health conditions, age, and gender. Among 119 participants, 43% had a history of solitary confinement and 28% screened positive for PTSD symptoms. Those who reported a history of solitary confinement were more likely to report PTSD symptoms than those without solitary confinement (43 vs. 16%, p symptoms among individuals accessing primary care following release from prison. Larger studies should confirm these findings.

  15. Confining pressure effects on stress intensity factors: A 3D finite ...

    African Journals Online (AJOL)

    A large number of 3D finite element models were analyzed for investigating the effect of various confining pressure levels on the fracture behaviour of brazilian disc specimen. In the finite element models a uniformly distributed confining pressure in the range of 0 MPa to 20 MPa is applied to all sides of the test specimen.

  16. Relationship Between Diurnal Changes of Net Photosynthetic Rate and Influencing Factors in Rice under Saline Sodic Stress

    Directory of Open Access Journals (Sweden)

    Fu Yang


    Full Text Available The net photosynthetic rate of flag leaves and influencing factors under saline sodic soil conditions were investigated at the full heading stage of rice. The net photosynthetic rate of rice leaves showed a double-peak curve in a day in both non-saline sodic and saline sodic soil treatments. The first peak of the net photosynthetic rate appeared at 9:00–10:00 and 9:00 in the saline sodic and non-saline sodic soil treatments, respectively, whereas the second peak both at 14:00. The midday depression of the net photosynthetic rate always appeared regardless of non-saline sodic or saline sodic soil conditions. In addition, the net photosynthetic rate significantly decreased in all day under saline sodic conditions compared with that under non-saline sodic conditions. Some differences were observed in correlation characters between the net photosynthetic rate and all influencing factors during 9:00–13:00. Under non-saline sodic conditions, the diurnal changes of the net photosynthetic rate in a day were mainly caused by stomatal conductance, and the limitation value and the stomatal factors served as determinants; whereas under saline sodic stress, the diurnal changes of the net photosynthetic rate in a day were mainly caused by non stomatal factors including light intensity and air temperature.

  17. Confining pressure effects on stress intensity factors: A 3D finite ...

    African Journals Online (AJOL)

    and extending artificial fractures in hydraulic fracturing depends strongly on fracture toughness of formation rocks in the petroleum reservoir. These rock masses are usually subjected to very high confining pressures at in situ conditions. (especially in cases with typical depths of. 7000-8000 m). Fracture toughness is an.

  18. The impact of chronic stress burden of 520-d isolation and confinement on the physiological response to subsequent acute stress challenge. (United States)

    Yi, Buqing; Matzel, Sandra; Feuerecker, Matthias; Hörl, Marion; Ladinig, Camilla; Abeln, Vera; Choukèr, Alexander; Schneider, Stefan


    Collective evidence indicates that previous exposure to stressful condition might be able to induce changes in brain structure, HPA axis activity and related neurotransmission, and accordingly affect physiological responses to subsequent challenges. During long-term spaceflight, space travelers have to live under the condition of isolation and confinement in the spacecraft for a long period. It is still largely unknown if this kind of chronic stress burden can induce any long-lasting changes. To address this question, following 520-d isolation and confinement simulating a flight to Mars, the participants and a matched control group were exposed to an acute stress challenge called parabolic flight. Brain cortical activity, HPA axis activity, and sympathetic adrenal-medullary system response were monitored by EEG signal, cortisol secretion, and catecholamine production, respectively. We observed enhanced EEG signals, elevated cortisol levels and increased adrenaline productions. A group effect on cortisol output was revealed showing higher cortisol peak levels in the Mars520 group as compared to the control group, suggesting that HPA axis was to a certain extent more activated in the subjects who had chronic stress experience. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Occupational stress in submariners: the impact of isolated and confined work on psychological well-being. (United States)

    Brasher, Kate S; Dew, Angela B C; Kilminster, Shaun G; Bridger, Robert S


    This study aimed to identify work-related and personal factors associated with occupational stress in submariners. Work and well-being questionnaires were distributed to 219 male submariners (mean age 34 years), as part of a larger cohort study involving a stratified sample of 4951 Royal Navy (RN) personnel. The stress rate in submariners was 40%; significantly higher than the stress rate in the general RN, although once demographic factors were controlled for in a matched control sample, this difference was no longer significant. A summary model accounted for 49% of the variance in submariner stress, with key differences emerging between the occupational factors associated with stress in submariners and in the general RN. The longitudinal nature of this study permits stress in submariners to be monitored over 5 years, which will provide valuable insights into the chronicity of stress in this specialised occupational group. STATEMENT OF RELEVANCE: This paper contributes to the current literature on the negative impact of working in isolated conditions. It is demonstrated that occupational stress in submarines can be partially explained using current theories of stress in the workplace. However, the constraints of a restricted environment introduce additional factors which can also be associated with occupational stress.

  20. Is the effect of alcohol on risk of stroke confined to highly stressed persons?

    DEFF Research Database (Denmark)

    Nielsen, N R; Truelsen, T; Barefoot, J C


    setting. We aimed to examine whether the association between alcohol and stroke depends on level of self-reported stress in a large prospective cohort. METHODS: The 5,373 men and 6,723 women participating in the second examination of the Copenhagen City Heart Study in 1981-1983 were asked at baseline......BACKGROUND: Psychological stress and alcohol are both suggested as risk factors for stroke. Further, there appears to be a close relation between stress and alcohol consumption. Several experimental studies have found alcohol consumption to reduce the immediate effects of stress in a laboratory...... about their self-reported level of stress and their weekly alcohol consumption. The participants were followed-up until 31st of December 1997 during which 880 first ever stroke events occurred. Data were analysed by means of Cox regression modelling. RESULTS: At a high stress level, weekly total...

  1. Cross-Sectional Unification on the Stress-Strain Model of Concrete Subjected to High Passive Confinement by Fiber-Reinforced Polymer

    Directory of Open Access Journals (Sweden)

    Yu-Gui Cao


    Full Text Available The stress-strain behavior of concrete can be improved by providing a lateral passive confining pressure, such as fiber-reinforced polymer (FRP wrapping. Many axial stress-strain models have been proposed for FRP-confined concrete columns. However, few models can predict the stress-strain behavior of confined concrete columns with more than two specified cross-sections. A stress-strain model of FRP-confined concrete columns with cross-sectional unification was developed in this paper based on a database from the existing literature that includes circular, square, rectangular and elliptical concrete columns that are highly confined by FRP jackets. Using the database, the existing theoretical models were evaluated. In addition, the ultimate stress and strain models with cross-sectional unification were proposed using two parameters: the cross-sectional aspect ratio and corner radius ratio. The elliptical cross-section can be considered as a rectangular one with a special corner radius for the model calculations. A simple and accurate model of the equivalent corner radius ratio for elliptical columns was proposed. Compared to the other existing models and experimental data, the proposed models show good performance.

  2. Discovery of Stationary Operation of Quiescent H-mode Plasmas with Net-Zero NBI Torque and High Energy Confinement on DIII-D (United States)

    Burrell, Keith


    Experiments this summer in DIII-D have used edge turbulence control to achieve stationary, high confinement operation without Edge Localized Mode (ELM) instabilities and with no external torque input. Eliminating the ELM-induced heat bursts and controlling plasma stability at low rotation represent two of the great challenges for fusion energy. By exploiting edge turbulence in a novel manner, we achieved outstanding tokamak performance, well above the H98 international tokamak energy confinement scaling (H98 =1.25), thus meeting an additional confinement challenge that is usually difficult at low torque. The new regime is triggered in double null plasmas by ramping the injected torque to zero and then maintaining it there. This lowers ExB rotation shear in the plasma edge, allowing low-k, broadband, electromagnetic turbulence to increase. In the H-mode edge, a narrow transport barrier usually grows until MHD instability (a peeling ballooning mode) leads to the ELM heat burst. However, the increased turbulence reduces the pressure gradient, allowing the development of a broader and thus higher transport barrier. A 60% increase in pedestal pressure and 40% increase in energy confinement result. Strong double-null plasma shaping raises the threshold for the ELM instability, allowing the plasma to reach a transport-limited state near but below the explosive ELM stability boundary. The resulting plasmas have burning-plasma-relevant betan =1.6-1.8 and run without the need for extra torque from 3D magnetic fields. To date, stationary conditions have been produced for 2 s or 12 energy confinement times, limited only by external hardware constraints. Stationary operation with improved pedestal conditions is highly significant for future burning plasma devices, since operation without ELMs at low rotation and good confinement is key for fusion energy production. Supported by the US DOE under DE-FC02-04ER54698.

  3. Urban expansion brought stress to food security in China: Evidence from decreased cropland net primary productivity. (United States)

    He, Chunyang; Liu, Zhifeng; Xu, Min; Ma, Qun; Dou, Yinyin


    Cropland net primary productivity (CNPP) is a crucial indicator of grain productivity and food security. However, assessments of the impact of urban expansion on the CNPP in China have been inadequate owing to data limitations. In this paper, our objective was to assess the impact of urban expansion on the CNPP in China from 1992 to 2015 in a spatially explicit manner. We first obtained the CNPP before urban expansion between 1992 and 2015 in China using the Carnegie-Ames-Stanford Approach (CASA) model. We then assessed the impact of urban expansion on the CNPP from 1992 to 2015 at multiple scales (the whole country, agricultural zones, and urban expansion hotspots) by combining the CNPP before urban expansion with the urban land coverage time series extracted from multi-source remotely sensed data. We found that the total loss of the CNPP due to urban expansion from 1992 to 2015 was 13.77TgC, which accounts for 1.88% of the CNPP before urban expansion in China. This CNPP loss resulted in a 12.45-million-ton decrease in grain production in China, corresponding to a reduction in the mean annual grain self-sufficiency rate of 2%. Therefore, we concluded that rapid urban expansion from 1992 to 2015 caused stress to China's food security. We suggest that it is still vital for China to effectively protect cropland to improve the urbanization level to 60% by 2020. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Effects of methods of confinement during transportation of market pigs on their behavior, stress and injury

    Directory of Open Access Journals (Sweden)

    Pongchan Na-Lampang


    Full Text Available The objective of this study was to compare the effects of transport market pigs in individual crates vs. in groups ontheir behavior, stress and injury. The pigs were transported for 1 h on a distance of 70 km. The stocking densities were 0.35m2/pig and 0.48 m2 for groups and individual crates treatment, respectively. During loading, the group pigs had higher frequencies of climbing, slipping and turning around than the crate pigs. During transport, the group pigs engaged in fightingand agonistic interactions. There were no differences (P>0.05 between the two treatments in rectal temperature, respiratoryrate and saliva cortisol level. Pigs kept in crates had lower (P<0.05 skin bruise scores but higher proportion of nonambulatorypigs than those kept in groups. In conclusion, transport in crates caused less agitation behaviors and injuries than transportin groups, but there was no differences in stress indicators.

  5. [Effects of lead stress on net photosynthetic rate, SPAD value and ginsenoside production in Ginseng (Panax ginseng)]. (United States)

    Liang, Yao; Jiang, Xiao-Li; Yang, Fen-Tuan; Cao, Qing-Jun; Li, Gang


    The paper aimed to evaluate the effects of lead stress on photosynthetic performance and ginsenoside content in ginseng (Panax ginseng). To accomplish this, three years old ginseng were cultivated in pot and in phytotron with different concentrations of lead, ranging from 0 to 1000 mg x kg(-1) soil for a whole growth period (about 150 days). The photosynthetic parameters in leaves and ginsenoside content in roots of ginseng were determined in green fruit stage and before withering stage, respectively. In comparison with the control, net photosynthetic rate and SPAD value in ginseng leaves cultivated with 100 and 250 mg x kg(-1) of lead changed insignificantly, however, ginseng supplied with 500 and 1 000 mg x kg(-1) of lead showed a noticeably decline in the net rate of photosynthesis and SPAD value (P lead, with decline of 57.8%,11.0%, respectively. Total content of ginsenoside in ginseng roots cultivated with 100 mg x kg(-1) of lead showed insignificantly change compared to the control, but the content increased remarkably in treatments supplied with 250, 500, 1 000 mg x kg(-1) of lead (P lead. The net photosynthetic rate and SPAD value in leaves of ginseng both showed significantly negative linear correlations with lead stress level (P lead concentration was also observed (P lead negatively affects photosynthetic performance in ginseng leaves, but benefits for accumulation of secondary metabolism (total content of ginsenoside) in ginseng root.

  6. Effectiveness and feasibility of Narrative Exposure Therapy (NET) in patients with borderline personality disorder and posttraumatic stress disorder - a pilot study

    National Research Council Canada - National Science Library

    Steuwe, Carolin; Rullkötter, Nina; Ertl, Verena; Berg, Michaela; Neuner, Frank; Beblo, Thomas; Driessen, Martin


    ...) and Posttraumatic Stress Disorder (PTSD). Eleven patients (1 male, 10 female) without previous stabilization periods or the absence of intentional self-injury received NET during a ten-week inpatient program...

  7. The causal role of fatigue in the stress-perceived health relationship: a MetroNet study. (United States)

    Maghout-Juratli, Sham; Janisse, James; Schwartz, Kendra; Arnetz, Bengt B


    We conducted a cross-sectional survey of 4 primary care MetroNet centers in metropolitan Detroit. Our objective was to describe the causal role of fatigue in the relationship among stress, stress resiliency, and perceived health in primary care. Fatigue is a public health problem that has been linked to stress and poor health. The causal role of fatigue between stress and perceived health is unknown. Four hundred surveys were distributed to adult patients in 4 primary care centers in metropolitan Detroit between 2006 and 2007. Internal consistency reliabilities and principal factor analyses were calculated for the key psychological scales. Perceived health is the primary outcome. Path models were used to study the relationship among stress, fatigue, and perceived health. We also modeled the impact of select stress resiliency factors including sleep, recovery, and social support. Of the 400 distributed surveys, 315 (78.7%) had a response rate of 70% or more and were included in the analysis. Respondents were predominantly middle aged (median age, 43 years); female (58.7%); and African American (52.0%). The majority worked full time (56.5%); did not have a college degree (77.7%); and were not married (55.2%). Fatigue was reported by 59% of respondents, 42.7% of which was unexplained. The path model supported the causal role of fatigue between stress and perceived health. The positive effects of sleep, recovery, and social support on fatigue, stress, and perceived health were validated. Fatigue was common in this metropolitan primary care environment and completely mediated the relationship between stress and poor perceived health. Therefore, stress, when significant enough to cause fatigue, may lead to poor health.

  8. Use of microarray technology to assess the time course of liver stress response after confinement exposure in gilthead sea bream (Sparus aurata L.

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    Cairns Michael T


    Full Text Available Abstract Background Selection programs for growth and stress traits in cultured fish are fundamental to the improvement of aquaculture production. The gilthead sea bream (Sparus aurata is the main aquacultured species in the Mediterranean area and there is considerable interest in the genetic improvement of this species. With the aim of increasing the genomic resources in gilthead sea bream and identifying genes and mechanisms underlying the physiology of the stress response, we developed a cDNA microarray for gilthead sea bream that is enriched by suppression substractive hybridization with stress and immunorelevant genes. This microarray is used to analyze the dynamics of gilthead sea bream liver expression profile after confinement exposure. Results Groups of confined and control juvenile fish were sampled at 6, 24, 72 and 120 h post exposure. GeneSpring analyses identified 202 annotated genes that appeared differentially expressed at least at one sampling time (P Conclusions Collectively, these findings show the complex nature of the adaptive stress response with a clear indication that the ER is an important control point for homeostatic adjustments. The study also identifies metabolic pathways which could be analyzed in greater detail to provide new insights regarding the transcriptional regulation of the stress response in fish.

  9. Research of the relationship between delayed fluorescence and net photosynthesis rate in spinach under NaCl stress (United States)

    Zhang, Lingrui; Xing, Da


    Under NaCl stress conditions, the relationship between delayed fluorescence (DF) and net photosynthesis rate (Pn) in detached leaves of spinach (Spinacia oleracea L.) was surveyed. Results showed that the changes in DF intensity of the spinach leaves directly exposed to different NaCl concentrations demonstrated considerably high consistency with that in Pn. Incubation of the leaves in 200mmol/L NaCl induced a gradual increase and subsequent decline of the DF intensity and Pu, whereas incubation of the leaves in 300mmol/L NaCl induced a continuous decline of the DF intensity and Pn, suggesting that DF bad the same response to duration of treatment of different NaC1 concentrations with Pn. Both DF and Pn showed maximal Ca 2+ antagonism effects on stress of high concentration NaC1 when the concentration of CaC1 II reached l5mmolfL. All the results demonstrated that DF has an excellent correlation with Pn and can be used as a sensitive test for the state of photosynthetic apparatus under salt stress physiology.

  10. Plasma confinement

    CERN Document Server

    Hazeltine, R D


    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  11. GEM2Net: from gene expression modeling to -omics networks, a new CATdb module to investigate Arabidopsis thaliana genes involved in stress response. (United States)

    Zaag, Rim; Tamby, Jean Philippe; Guichard, Cécile; Tariq, Zakia; Rigaill, Guillem; Delannoy, Etienne; Renou, Jean-Pierre; Balzergue, Sandrine; Mary-Huard, Tristan; Aubourg, Sébastien; Martin-Magniette, Marie-Laure; Brunaud, Véronique


    CATdb ( is a database providing a public access to a large collection of transcriptomic data, mainly for Arabidopsis but also for other plants. This resource has the rare advantage to contain several thousands of microarray experiments obtained with the same technical protocol and analyzed by the same statistical pipelines. In this paper, we present GEM2Net, a new module of CATdb that takes advantage of this homogeneous dataset to mine co-expression units and decipher Arabidopsis gene functions. GEM2Net explores 387 stress conditions organized into 18 biotic and abiotic stress categories. For each one, a model-based clustering is applied on expression differences to identify clusters of co-expressed genes. To characterize functions associated with these clusters, various resources are analyzed and integrated: Gene Ontology, subcellular localization of proteins, Hormone Families, Transcription Factor Families and a refined stress-related gene list associated to publications. Exploiting protein-protein interactions and transcription factors-targets interactions enables to display gene networks. GEM2Net presents the analysis of the 18 stress categories, in which 17,264 genes are involved and organized within 681 co-expression clusters. The meta-data analyses were stored and organized to compose a dynamic Web resource. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  12. Relationship Between Diurnal Changes of Net Photosynthetic Rate and Influencing Factors in Rice under Saline Sodic Stress


    Fu Yang; Zheng-wei Liang; Zhi-chun Wang; Yuan Chen


    The net photosynthetic rate of flag leaves and influencing factors under saline sodic soil conditions were investigated at the full heading stage of rice. The net photosynthetic rate of rice leaves showed a double-peak curve in a day in both non-saline sodic and saline sodic soil treatments. The first peak of the net photosynthetic rate appeared at 9:00–10:00 and 9:00 in the saline sodic and non-saline sodic soil treatments, respectively, whereas the second peak both at 14:00. The midday depr...

  13. Improvements to water use and water stress estimates with the addition of IR and net radiometers to weather stations (United States)

    Evapotranspiration (ET) is often estimated with the Penman-Monteith (P-M) equation. Net radiation (Rn) is a major component of the surface energy balance and an input to the P-M equation, but it is challenging and expensive to measure accurately. For these reasons, most weather stations do not inclu...

  14. Leishmanial lipid affords protection against oxidative stress induced hepatic injury by regulating inflammatory mediators and confining apoptosis progress. (United States)

    Chatterjee, Nabanita; Das, Subhadip; Bose, Dipayan; Banerjee, Somenath; Jha, Tarun; Saha, Krishna Das


    Persistence of liver injury alters the internal milieu, promotes deregulation of inflammatory factors, and leads to dysplastic lesions like fibrosis, cirrhosis to hepatocellular carcinoma. Our previous study revealed that leishmanial lipid (pLLD) exerts potential anti-inflammatory activity in sepsis associated hepatic injury. We now show that pLLD gives protection against chemical induced hepatotoxicity in murine system. The beneficial effect of treatment with pLLD on such hepatic injury in mice was analyzed using different assays including ELISA, FACS, western blot and immunohistochemical analysis. pLLD significantly suppressed serum enzymes and rectified the histopathological alteration to induce the antioxidant level in CCl4 intoxicated liver. Levels of several growth factors including TGF-β, HGF, and EGF were significantly improved in serum and hepatic tissue with consequent reduction of caspase activities and expressions of Bad, Bax, p53, and NF-κBp65. Moreover, pLLD modulated inflammatory responses by decreasing the production of several cytokines and chemokines, thus preventing the infiltration of immune cells to the damaged area. It accelerated the repair process in liver damage with modulation of signalling cascade via alteration of apoptotic factors. Our experimental approaches suggest that pLLD effectively prevents liver injury mainly through down regulation of oxidative stress and inflammatory response towards anti-apoptotic changes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Magnetic confinement

    Energy Technology Data Exchange (ETDEWEB)

    Batistoni, Paola; De Marco, Francesco; Pieroni, Leonardo (ed.)


    The Frascati Tokamak Upgrade (FTU) is a compact, high-magnetic-field tokamak capable of operating at density and magnetic field values similar to, or even encompassing, those of International Thermonuclear Experimental Reactor (ITER) and therefore provides a unique opportunity to explore physics issues that are directly relevant to ITER. During 2004 the experimental activities were focussed on fully exploiting the lower hybrid system (for generating and controlling the plasma current) and the electron cyclotron heating system (joint experiment with the Institute of Plasma Physics of the National Research Council, Milan). With all four gyrotrons in operation, full electron cyclotron power was achieved up to a record level of 1.5 MW. By simultaneously injecting lower hybrid waves, to tailor the plasma current radial profile, and electron cyclotron waves, to heat the plasma centre, good confinement regimes with internal transport barriers were obtained at the highest plasma density values ever achieved for this operation regime (n {approx}1.5X10{sup 20}m{sup -3}). Specific studies were devoted to optimising the coupling of lower hybrid waves to the plasma (by real-time control of the plasma position) and to generating current by electron cyclotron current drive. The new scanning CO{sub 2} interferometer (developed by the Reversed Field Experiment Consortium) for high spatial and time resolution (1 cm/50 {mu}s) density profile measurements was extensively used. The Thomson scattering diagnostic was upgraded and enabled observation of scattered signals associated with the Confinement background plasma dynamics. As for theoretical studies on the dynamics of turbulence in plasmas, the transition from Bohm-like scaling to gyro-Bohm scaling of the local plasma diffusivity was demonstrated on the basis of a generalised four wave model (joint collaboration with Princeton Plasma Physics Laboratory and the University of California at Irvine). The transition from weak to strong

  16. Net Locality

    DEFF Research Database (Denmark)

    de Souza e Silva, Adriana Araujo; Gordon, Eric

    Provides an introduction to the new theory of Net Locality and the profound effect on individuals and societies when everything is located or locatable. Describes net locality as an emerging form of location awareness central to all aspects of digital media, from mobile phones, to Google Maps...... of emerging technologies, from GeoCities to GPS, Wi-Fi, Wiki Me, and Google Android....

  17. Net Neutrality

    DEFF Research Database (Denmark)

    Savin, Andrej


    Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else.......Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else....

  18. A critically appraised topic (CAT) to compare the effects of single and multi-cat housing on physiological and behavioural measures of stress in domestic cats in confined environments (United States)


    Background Domestic cats have evolved from solitary, asocial predators and whilst they may display social behaviours, they can still exist as solitary survivors. Over-population and relinquishment of pet cats are ubiquitous problems worldwide, and rehoming centres (also known as rescues/ shelters) aim to ameliorate this by holding cats in confinement for a variable period until a new home is found. The provision of optimal housing for large numbers of cats in close confinement, such as in rehoming centres, is therefore inherently difficult. Under these conditions there is the potential for individuals to develop signs of physical and psychological ill health, and thus experience compromised welfare. Available information regarding housing practices that maximise welfare currently provides conflicting results, and as a consequence there are no unanimous housing recommendations. The aim of this study was therefore to review the evidence on the impact of single housing compared to multi-cat housing on stress in confined cats, as measured by physiological and/or behavioural outcomes. The review was conducted using a Critically Appraised Topic (CAT) format. A systematic search of electronic databases (CAB Abstracts, Zoological Records and Medline) was carried out to identify peer-reviewed literature comparing single and multi-cat housing in confined environments. Results A total of 959 papers were initially identified, six of which met sufficient criteria based on their relevance to be included within this review. All of the studies had significant limitations in design and methodology, including a lack of information on how groups were assigned, inconsistent handling and enrichment provision between groups, and lack of information on the socialisation status of cats. Conclusions Whilst some studies suggested that single housing may be less stressful for cats, others suggested group housing was less stressful. Several other important factors were however identified as

  19. A critically appraised topic (CAT) to compare the effects of single and multi-cat housing on physiological and behavioural measures of stress in domestic cats in confined environments. (United States)

    Finka, Lauren R; Ellis, Sarah Lh; Stavisky, Jenny


    Domestic cats have evolved from solitary, asocial predators and whilst they may display social behaviours, they can still exist as solitary survivors. Over-population and relinquishment of pet cats are ubiquitous problems worldwide, and rehoming centres (also known as rescues/ shelters) aim to ameliorate this by holding cats in confinement for a variable period until a new home is found. The provision of optimal housing for large numbers of cats in close confinement, such as in rehoming centres, is therefore inherently difficult. Under these conditions there is the potential for individuals to develop signs of physical and psychological ill health, and thus experience compromised welfare. Available information regarding housing practices that maximise welfare currently provides conflicting results, and as a consequence there are no unanimous housing recommendations. The aim of this study was therefore to review the evidence on the impact of single housing compared to multi-cat housing on stress in confined cats, as measured by physiological and/or behavioural outcomes. The review was conducted using a Critically Appraised Topic (CAT) format. A systematic search of electronic databases (CAB Abstracts, Zoological Records and Medline) was carried out to identify peer-reviewed literature comparing single and multi-cat housing in confined environments. A total of 959 papers were initially identified, six of which met sufficient criteria based on their relevance to be included within this review. All of the studies had significant limitations in design and methodology, including a lack of information on how groups were assigned, inconsistent handling and enrichment provision between groups, and lack of information on the socialisation status of cats. Whilst some studies suggested that single housing may be less stressful for cats, others suggested group housing was less stressful. Several other important factors were however identified as potential mediators of stress

  20. Effect of Aluminium Confinement on ANFO Detonation (United States)

    Short, Mark; Jackson, Scott; Kiyanda, Charles; Shinas, Mike; Hare, Steve; Briggs, Matt


    Detonations in confined non-ideal high explosives often have velocities below the confiner sound speed. The effect on detonation propagation of the resulting subsonic flow in the confiner (such as confiner stress waves traveling ahead of the main detonation front or upstream wall deflection into the HE) has yet to be fully understood. Previous work by Sharpe and Bdzil (J. Eng. Math, 2006) has shown that for subsonic confiner flow, there is no limiting thickness for which the detonation dynamics are uninfluenced by further increases in wall thickness. The critical parameters influencing detonation behavior are the wall thickness relative to the HE reaction zone size, and the difference in the detonation velocity and confiner sound speed. Additional possible outcomes of subsonic flow are that for increasing thickness, the confiner is increasingly deflected into the HE upstream of the detonation, and that for sufficiently thick confiners, the detonation speed could be driven up to the sound speed in the confiner. We report here on a further series of experiments in which a mixture of ammonium nitrate and fuel oil (ANFO) is detonated in aluminum confiners with varying HE charge diameter and confiner thickness, and compare the results with the outcomes suggested by Sharpe and Bdzil.

  1. Absence of reptation in highly confined polymers. (United States)

    Srivastava, S; Basu, J K


    We present results of mechanical stress relaxation measurements on polymers confined at the air-water interface in the form of a monolayer. Systematic measurements allow, to our knowledge, for the first time, observation of the scaling of the stress relaxation time of the highly confined polymers as a function of both surface concentration and molecular weight. The observed scaling is found to be very close to that expected for motion of unentangled polymer solutions with hydrodynamic interactions. Our experimental observations thus clearly rule out the possibility of entanglement and hence reptation as a mode of relaxation in such highly confined polymeric systems.

  2. RESTful NET

    CERN Document Server

    Flanders, Jon


    RESTful .NET is the first book that teaches Windows developers to build RESTful web services using the latest Microsoft tools. Written by Windows Communication Foundation (WFC) expert Jon Flanders, this hands-on tutorial demonstrates how you can use WCF and other components of the .NET 3.5 Framework to build, deploy and use REST-based web services in a variety of application scenarios. RESTful architecture offers a simpler approach to building web services than SOAP, SOA, and the cumbersome WS- stack. And WCF has proven to be a flexible technology for building distributed systems not necessa

  3. Mycorrhiza-induced lower oxidative burst is related with higher antioxidant enzyme activities, net H2O2 effluxes, and Ca2+ influxes in trifoliate orange roots under drought stress. (United States)

    Zou, Ying-Ning; Huang, Yong-Ming; Wu, Qiang-Sheng; He, Xin-Hua


    Mechanisms of arbuscular mycorrhiza (AM)-induced lower oxidative burst of host plants under drought stress (DS) are not elucidated. A noninvasive microtest technology (NMT) was used to investigate the effects of Funneliformis mosseae on net fluxes of root hydrogen peroxide (H2O2) and calcium ions (Ca2+) in 5-month-old Poncirus trifoliata, in combination with catalase (CAT) and superoxide dismutase (SOD) activities as well as tissue superoxide radical (O2•-) and H2O2 concentrations under DS and well-watered (WW) conditions. A 2-month DS (55% maximum water holding capacity of growth substrates) significantly inhibited AM fungal root colonization, while AM symbiosis significantly increased plant biomass production, irrespective of water status. F. mosseae inoculation generally increased SOD and CAT activity but decreased O2•- and H2O2 concentrations in leaves and roots under WW and DS. Compared with non-AM seedlings, roots of AM seedlings had significantly higher net H2O2 effluxes and net Ca2+ influxes, especially in the meristem zone, but lower net H2O2 efflux in the elongation zone. Net Ca2+ influxes into roots were significantly positively correlated with root net H2O2 effluxes but negatively with root H2O2 concentrations. Results from this study suggest that AM-induced lower oxidative burst is related with higher antioxidant enzyme activities, root net H2O2 effluxes, and Ca2+ influxes under WW and DS.

  4. Petri Nets

    Indian Academy of Sciences (India)

    Associate Professor of. Computer Science and. Automation at the Indian. Institute of Science,. Bangalore. His research interests are broadly in the areas of stochastic modeling and scheduling methodologies for future factories; and object oriented modeling. GENERAL I ARTICLE. Petri Nets. 1. Overview and Foundations.

  5. Petri Nets

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 8. Petri Nets - Overview and Foundations. Y Narahari. General Article Volume 4 Issue 8 August 1999 pp ... Author Affiliations. Y Narahari1. Department ot Computer Science and Automation, Indian Institute of Science, Bangalore 560 012, India.

  6. Effects of high sound speed confiners on ANFO detonations (United States)

    Kiyanda, Charles; Jackson, Scott; Short, Mark


    The interaction between high explosive (HE) detonations and high sound speed confiners, where the confiner sound speed exceeds the HE's detonation speed, has not been thoroughly studied. The subsonic nature of the flow in the confiner allows stress waves to travel ahead of the main detonation front and influence the upstream HE state. The interaction between the detonation wave and the confiner is also no longer a local interaction, so that the confiner thickness now plays a significant role in the detonation dynamics. We report here on larger scale experiments in which a mixture of ammonium nitrate and fuel oil (ANFO) is detonated in aluminium confiners with varying charge diameter and confiner thickness. The results of these large-scale experiments are compared with previous large-scale ANFO experiments in cardboard, as well as smaller-scale aluminium confined ANFO experiments, to characterize the effects of confiner thickness.

  7. Frictional properties of confined polymers

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, Vladimir N; Persson, Bo N J


    We present molecular dynamics friction calculations for confined hydrocarbon solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: a) polymer sliding against a hard substrate, and b) polymer sliding on polymer. In the first setup the shear stresses are relatively...... independent of molecular length. For polymer sliding on polymer the friction is significantly larger, and dependent on the molecular chain length. In both cases, the shear stresses are proportional to the squeezing pressure and finite at zero load, indicating an adhesional contribution to the friction force...


    Directory of Open Access Journals (Sweden)

    Javad Khazaei


    Full Text Available Helical piles are environmentally friendly and economical deep foundations that, due to environmental considerations, are excellent additions to a variety of deep foundation alternatives available to the practitioner. Helical piles performance depends on soil properties, the pile geometry and soil-pile interaction. Helical piles can be a proper alternative in sensitive environmental sites if their bearing capacity is sufficient to support applied loads. The failure capacity of helical piles in this study was measured via an experimental research program that was carried out by Frustum Confining Vessel (FCV. FCV is a frustum chamber by approximately linear increase in vertical and lateral stresses along depth from top to bottom. Due to special geometry and applied bottom pressure, this apparatus is a proper choice to test small model piles which can simulate field stress conditions. Small scale helical piles are made with either single helix or more helixes and installed in fine grained sand with three various densities. Axial loading tests including compression and tension tests were performed to achieve pile ultimate capacity. The results indicate the helical piles behavior depends essentially on pile geometric characteristics, i.e. helix configuration and soil properties. According to the achievements, axial uplift capacity of helical model piles is about equal to usual steel model piles that have the helixes diameter. Helical pile compression bearing capacity is too sufficient to act as a medium pile, thus it can be substituted other piles in special geoenvironmental conditions. The bearing capacity also depends on spacing ratio, S/D, and helixes diameter.

  9. Heat stress of two tropical seagrass species during low tides - impact on underwater net photosynthesis, dark respiration and diel in situ internal aeration. (United States)

    Pedersen, Ole; Colmer, Timothy D; Borum, Jens; Zavala-Perez, Andrea; Kendrick, Gary A


    Seagrasses grow submerged in aerated seawater but often in low O2 sediments. Elevated temperatures and low O2 are stress factors. Internal aeration was measured in two tropical seagrasses, Thalassia hemprichii and Enhalus acoroides, growing with extreme tides and diel temperature amplitudes. Temperature effects on net photosynthesis (PN ) and dark respiration (RD ) of leaves were evaluated. Daytime low tide was characterized by high pO2 (54 kPa), pH (8.8) and temperature (38°C) in shallow pools. As PN was maximum at 33°C (9.1 and 7.2 μmol O2  m(-2) s(-1) in T. hemprichii and E. acoroides, respectively), the high temperatures and reduced CO2 would have diminished PN , whereas RD increased (Q10 of 2.0-2.7) above that at 33°C (0.45 and 0.33 μmol O2  m(-2)  s(-1) , respectively). During night-time low tides, O2 declined resulting in shoot base anoxia in both species, but incoming water containing c. 20 kPa O2 relieved the anoxia. Shoots exposed to 40°C for 4 h showed recovery of PN and RD , whereas 45°C resulted in leaf damage. These seagrasses are 'living near the edge', tolerant of current diel O2 and temperature extremes, but if temperatures rise both species may be threatened in this habitat. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  10. Plasma cortisol and metabolite level profiles in two isogenic strains of common carp during confinement

    NARCIS (Netherlands)

    Ruane, N.M.; Huisman, E.A.; Komen, J.


    A rapid increase in common carp Cyprinus carpio plasma cortisol levels was noted, in two experiments, after 30 mins of a 3 h net confinement, which was sustained while the fish were held in the nets. After release from the nets, cortisol levels returned to control values in 1 h. Plasma glucose and

  11. Confinement Aquaculture. Final Report. (United States)

    Delaplaine School District, AR.

    The Delaplaine Agriculture Department Confinement Project, begun in June 1988, conducted a confinement aquaculture program by comparing the growth of channel catfish raised in cages in a pond to channel catfish raised in cages in the Black River, Arkansas. The study developed technology that would decrease costs in the domestication of fish, using…

  12. Dynamics in geometrical confinement

    CERN Document Server

    Kremer, Friedrich


    This book describes the dynamics of low molecular weight and polymeric molecules when they are constrained under conditions of geometrical confinement. It covers geometrical confinement in different dimensionalities: (i) in nanometer thin layers or self supporting films (1-dimensional confinement) (ii) in pores or tubes with nanometric diameters (2-dimensional confinement) (iii) as micelles embedded in matrices (3-dimensional) or as nanodroplets.The dynamics under such conditions have been a much discussed and central topic in the focus of intense worldwide research activities within the last two decades. The present book discusses how the resulting molecular mobility is influenced by the subtle counterbalance between surface effects (typically slowing down molecular dynamics through attractive guest/host interactions) and confinement effects (typically increasing the mobility). It also explains how these influences can be modified and tuned, e.g. through appropriate surface coatings, film thicknesses or pore...

  13. Elastic membranes in confinement. (United States)

    Bostwick, J B; Miksis, M J; Davis, S H


    An elastic membrane stretched between two walls takes a shape defined by its length and the volume of fluid it encloses. Many biological structures, such as cells, mitochondria and coiled DNA, have fine internal structure in which a membrane (or elastic member) is geometrically 'confined' by another object. Here, the two-dimensional shape of an elastic membrane in a 'confining' box is studied by introducing a repulsive confinement pressure that prevents the membrane from intersecting the wall. The stage is set by contrasting confined and unconfined solutions. Continuation methods are then used to compute response diagrams, from which we identify the particular membrane mechanics that generate mitochondria-like shapes. Large confinement pressures yield complex response diagrams with secondary bifurcations and multiple turning points where modal identities may change. Regions in parameter space where such behaviour occurs are then mapped. © 2016 The Author(s).

  14. Frost damage of concrete subject to confinement

    DEFF Research Database (Denmark)

    Hasholt, Marianne Tange


    When internal frost damage is observed in real concrete structures, the usual pattern is cracks with a preferred orientation parallel to the exposed surface. When exposing concrete with poor frost resistance to a standardised freeze/thaw test in the laboratory, the orientations of the resulting...... cracks are more or less random. The present study is an experimental study, which aims at investigating the influence of confinement during freeze/thaw action on the developed crack pattern. Confinement is established by mounting hose clamps on cylindrical test specimens, using similar test specimens...... without hose clamps as reference. The results show that confinement can change the outcome of a freeze/thaw test as regards extent of internal cracking, crack orientations, and amount of surface scaling. Thus it seems likely that the difference in confinement (and therefore also in stress state) can...

  15. Mass gap without confinement (United States)

    Faedo, Antón F.; Mateos, David; Pravos, David; Subils, Javier G.


    We revisit a one-parameter family of three-dimensional gauge theories with known supergravity duals. We show that three infrared behaviors are possible. For generic values of the parameter, the theories exhibit a mass gap but no confinement, meaning no linear quark-antiquark potential; for one limiting value of the parameter the theory flows to an infrared fixed point; and for another limiting value it exhibits both a mass gap and confinement. Theories close to these limiting values exhibit quasi-conformal and quasi-confining dynamics, respectively. Eleven-dimensional supergravity provides a simple, geometric explanation of these features.

  16. Frictional properties of confined polymers. (United States)

    Sivebaek, I M; Samoilov, V N; Persson, B N J


    We present molecular dynamics friction calculations for confined hydrocarbon solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: a) polymer sliding against a hard substrate, and b) polymer sliding on polymer. In the first setup the shear stresses are relatively independent of molecular length. For polymer sliding on polymer the friction is significantly larger, and dependent on the molecular chain length. In both cases, the shear stresses are proportional to the squeezing pressure and finite at zero load, indicating an adhesional contribution to the friction force. The friction decreases when the sliding distance is of the order of the molecular length indicating a strong influence of molecular alignment during run-in. The results of our calculations show good correlation with experimental work.

  17. Analysis of thermally-degrading, confined HMX

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, M.L.; Schmitt, R.G.; Renlund, A.M.


    The response of a thermally-degrading, confined HMX pellet is analyzed using a Reactive Elastic-Plastic (REP) constitutive model which is founded on the collapse and growth of internal inclusions resulting from physical and chemical processes such as forced displacement, thermal expansion, and/or decomposition. Axial stress predictions compare adequately to data. Deficiencies in the model and future directions are discussed.

  18. Shearing Nanometer-Thick Confined Hydrocarbon Films: Friction and Adhesion

    DEFF Research Database (Denmark)

    Sivebæk, I. M.; Persson, B. N. J.


    We present molecular dynamics (MD) friction and adhesion calculations for nanometer-thick confined hydrocarbon films with molecular lengths 20, 100 and 1400 carbon atoms. We study the dependency of the frictional shear stress on the confining pressure and sliding speed. We present results...

  19. The ESA Mice in Space (MIS) habitat: effects of cage confinement on neuromusculoskeletal structure and function and stress/behavior using wild-type C57Bl/6JRj mice in a modular science reference model (MSRM) test on ground (United States)

    Blottner, Dieter; Vico, Laurence; Jamon, D. Berckmansp L. Vicop Y. Liup R. Canceddap M.

    Background: Environmental conditions likely affect physiology and behaviour of mice used for Life Sciences Research on Earth and in Space. Thus, mice habitats with sufficient statistical numbers should be developed for adequate life support and care and that should meet all nesces-sary ethical and scientific requirements needed to successfully perform animal experimentation in Space. Aim of study: We here analysed the effects of cage confinement on the weightbear-ing musculoskeletal system, behaviour and stress of wild-type mice (C57BL/6JRj, 30 g b.wt., total n = 24) housed for 25 days in a prototypical ground-based MSRM (modular science ref-erence module) in the frame of breadboard activities for a fully automated life support habitat called "Mice in Space" (MIS) at the Leuven University, Belgium. Results: Compared with control housing (individually ventilated cages, IVC-mice) the MIS mice revealed no significant changes in soleus muscle size and myofiber distribution (type I vs. II) and quality of bone (3-D microarchitecture and mineralisation of calvaria, spine and femur) determined by confocal and micro-computed tomography. Corticosterone metabolism measured non-invasively (faeces) monitored elevated adrenocortical activity at only start of the MIS cage confinement (day 1). Behavioural tests (i.e., grip strength, rotarod, L/D box, elevated plus-maze, open field, ag-gressiveness) performed subsequently revealed only minor changes in motor performance (MIS vs. controls). Conclusions: The MIS habitat will not, on its own, produce major effects that could confound interpretation of data induced by microgravity exposure on orbit as planned for future biosatellite programmes. Sponsors: ESA-ESTEC, Noordwijk, NL

  20. Limits on rock strength under high confinement (United States)

    Renshaw, Carl E.; Schulson, Erland M.


    Understanding of deep earthquake source mechanisms requires knowledge of failure processes active under high confinement. Under low confinement the compressive strength of rock is well known to be limited by frictional sliding along stress-concentrating flaws. Under higher confinement strength is usually assumed limited by power-law creep associated with the movement of dislocations. In a review of existing experimental data, we find that when the confinement is high enough to suppress frictional sliding, rock strength increases as a power-law function only up to a critical normalized strain rate. Within the regime where frictional sliding is suppressed and the normalized strain rate is below the critical rate, both globally distributed ductile flow and localized brittle-like failure are observed. When frictional sliding is suppressed and the normalized strain rate is above the critical rate, failure is always localized in a brittle-like manner at a stress that is independent of the degree of confinement. Within the high-confinement, high-strain rate regime, the similarity in normalized failure strengths across a variety of rock types and minerals precludes both transformational faulting and dehydration embrittlement as strength-limiting mechanisms. The magnitude of the normalized failure strength corresponding to the transition to the high-confinement, high-strain rate regime and the observed weak dependence of failure strength on strain rate within this regime are consistent with a localized Peierls-type strength-limiting mechanism. At the highest strain rates the normalized strengths approach the theoretical limit for crystalline materials. Near-theoretical strengths have previously been observed only in nano- and micro-scale regions of materials that are effectively defect-free. Results are summarized in a new deformation mechanism map revealing that when confinement and strain rate are sufficient, strengths approaching the theoretical limit can be achieved in

  1. Compaction of granular material inside confined geometries

    Directory of Open Access Journals (Sweden)

    Benjy eMarks


    Full Text Available In both nature and the laboratory, loosely packed granular materials are often compacted inside confined geometries. Here, we explore such behaviour in a quasi-two dimensional geometry, where parallel rigid walls provide the confinement. We use the discrete element method to investigate the stress distribution developed within the granular packing as a result of compaction due to the displacement of a rigid piston. We observe that the stress within the packing increases exponentially with the length of accumulated grains, and show an extension to current analytic models which fits the measured stress. The micromechanical behaviour is studied for a range of system parameters, and the limitations of existing analytic models are described. In particular, we show the smallest sized systems which can be treated using existing models. Additionally, the effects of increasing piston rate, and variations of the initial packing fraction, are described.

  2. A flow cytometry-based screen of nuclear envelope transmembrane proteins identifies NET4/Tmem53 as involved in stress-dependent cell cycle withdrawal.

    Directory of Open Access Journals (Sweden)

    Nadia Korfali


    Full Text Available Disruption of cell cycle regulation is one mechanism proposed for how nuclear envelope protein mutation can cause disease. Thus far only a few nuclear envelope proteins have been tested/found to affect cell cycle progression: to identify others, 39 novel nuclear envelope transmembrane proteins were screened for their ability to alter flow cytometry cell cycle/DNA content profiles when exogenously expressed. Eight had notable effects with seven increasing and one decreasing the 4N:2N ratio. We subsequently focused on NET4/Tmem53 that lost its effects in p53(-/- cells and retinoblastoma protein-deficient cells. NET4/TMEM53 knockdown by siRNA altered flow cytometry cell cycle/DNA content profiles in a similar way as overexpression. NET4/TMEM53 knockdown did not affect total retinoblastoma protein levels, unlike nuclear envelope-associated proteins Lamin A and LAP2α. However, a decrease in phosphorylated retinoblastoma protein was observed along with a doubling of p53 levels and a 7-fold increase in p21. Consequently cells withdrew from the cell cycle, which was confirmed in MRC5 cells by a drop in the percentage of cells expressing Ki-67 antigen and an increase in the number of cells stained for ß-galactosidase. The ß-galactosidase upregulation suggests that cells become prematurely senescent. Finally, the changes in retinoblastoma protein, p53, and p21 resulting from loss of NET4/Tmem53 were dependent upon active p38 MAP kinase. The finding that roughly a fifth of nuclear envelope transmembrane proteins screened yielded alterations in flow cytometry cell cycle/DNA content profiles suggests a much greater influence of the nuclear envelope on the cell cycle than is widely held.

  3. Confinement for More Space

    DEFF Research Database (Denmark)

    Kipnusu, Wycliffe K.; Elsayed, Mohamed; Kossack, Wilhelm


    Broadband dielectric spectroscopy and positron annihilation lifetime spectroscopy are employed to study the molecular dynamics and effective free volume of 2-ethyl-1-hexanol (2E1H) in the bulk state and when confined in unidirectional nanopores with average diameters of 4, 6, and 8 nm. Enhanced α...

  4. Confinement at Large Nc

    NARCIS (Netherlands)

    Hooft, G. 't


    A discussion is given of the confinement mechanism in terms of the Abelian projection scheme, for a general number Nc of colors. There is a difficulty in the Nc to infinity limit that requires a careful treatment, as the charges of the condensing magnetic monopoles tend to infinity. We suggest that

  5. Growing instead of confining (United States)

    Sun, Yang-Kook; Yoon, Chong Seung


    Confining sulfur in high-surface-area carbon is a widely adapted approach in Li-S batteries, but it often results in low sulfur utilization and low energy density. Now, controlled nucleation of discrete Li2S particles on a network of low-surface-area carbon fibres provides a possible solution to the endemic problems of Li-S batteries.

  6. Polymers under Cylindrical Confinement (United States)

    Russell, Thomas


    Anodized alumina oxide (AAO) membranes offer a unique platform to investigate polymers under confinement. AAO membranes have been prepared where the diameters of the nanopores in the membrane have been varied from 8 to 50 nm by varying the anodization conditions. Capillary force is sufficiently large to draw high molecular weight polymers into the membrane, producing either nanotubes or nanorods. Polymer solutions can also be used place a thin film on the walls of the nanopores, forming nanotubes. With pore diameters less than the radius of gyration, a quantitative understanding of perturbations to chain dynamics due to geometric constraints was examined. We found a weak molecular weight-dependent mobility of polymers confined within AAO nanopores having diameters smaller than the dimension of the chains in the bulk. The measured mobility of polymers in the confined geometry was much higher than the mobility of the unconfined chain. Rayleigh instabilities in thin polymer films confined within nanoporous alumina membranes were also found where periodic undulations on the film surface were found to increase with time, eventually bridging across the cylindrical nanopore, resulting in the formation of polymer nanorods with a periodic array of encapsulated holes. With microphase separated block copolymers, where the characteristic period of the BCP morphology is comparable to the pore diameter, significant deviations from the bulk morphology as revealed by electron tomography. Small angle neutron scattering was also used to investigate the influence of cylindrical confinement on the order-to-disordered transition. This work was done in collaboration with T. J. McCarthy (UMass), K. Shin (Seoul National University), H. Jinnai (Kyoto University), D. Chen, J. Chen, H. Xiang, T. Kim, and P. Dobriyal, and was supported by the DOE, NSF MRSEC, NSF CHM.

  7. NA-NET numerical analysis net

    Energy Technology Data Exchange (ETDEWEB)

    Dongarra, J. [Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science]|[Oak Ridge National Lab., TN (United States); Rosener, B. [Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science


    This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host ```` at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message ``send index`` to netlib{at} The following report describes the current NA-NET system from both a user`s perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

  8. NA-NET numerical analysis net

    Energy Technology Data Exchange (ETDEWEB)

    Dongarra, J. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science Oak Ridge National Lab., TN (United States)); Rosener, B. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science)


    This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host'' at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message send index'' to netlib{at} The following report describes the current NA-NET system from both a user's perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

  9. Inertial Confinement fusion targets (United States)

    Hendricks, C. D.


    Inertial confinement fusion (ICF) targets are made as simple flat discs, as hollow shells or as complicated multilayer structures. Many techniques were devised for producing the targets. Glass and metal shells are made by using drop and bubble techniques. Solid hydrogen shells are also produced by adapting old methods to the solution of modern problems. Some of these techniques, problems, and solutions are discussed. In addition, the applications of many of the techniques to fabrication of ICF targets is presented.

  10. Confinement for Active Objects


    Florian Kammuller


    In this paper, we provide a formal framework for the security of distributed active objects. Active objects com-municate asynchronously implementing method calls via futures. We base the formal framework on a security model that uses a semi-lattice to enable multi-lateral security crucial for distributed architectures. We further provide a security type system for the programming model ASPfun of functional active objects. Type safety and a confinement property are presented. ASPfun thus reali...

  11. Net Ecosystem Carbon Flux (United States)

    U.S. Geological Survey, Department of the Interior — Net Ecosystem Carbon Flux is defined as the year-over-year change in Total Ecosystem Carbon Stock, or the net rate of carbon exchange between an ecosystem and the...

  12. Stress (United States)

    ... natural disaster. This type of stress can cause post-traumatic stress disorder (PTSD). Different people may feel stress in different ways. Some people experience digestive symptoms. Others may have headaches, sleeplessness, depressed mood, anger, ...

  13. Professional Enterprise NET

    CERN Document Server

    Arking, Jon


    Comprehensive coverage to help experienced .NET developers create flexible, extensible enterprise application code If you're an experienced Microsoft .NET developer, you'll find in this book a road map to the latest enterprise development methodologies. It covers the tools you will use in addition to Visual Studio, including Spring.NET and nUnit, and applies to development with ASP.NET, C#, VB, Office (VBA), and database. You will find comprehensive coverage of the tools and practices that professional .NET developers need to master in order to build enterprise more flexible, testable, and ext

  14. Confinement Contains Condensates

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, Stanley J.; Roberts, Craig D.; Shrock, Robert; Tandy, Peter C.


    Dynamical chiral symmetry breaking and its connection to the generation of hadron masses has historically been viewed as a vacuum phenomenon. We argue that confinement makes such a position untenable. If quark-hadron duality is a reality in QCD, then condensates, those quantities that have commonly been viewed as constant empirical mass-scales that fill all spacetime, are instead wholly contained within hadrons; i.e., they are a property of hadrons themselves and expressed, e.g., in their Bethe-Salpeter or light-front wave functions. We explain that this paradigm is consistent with empirical evidence, and incidentally expose misconceptions in a recent Comment.

  15. Working under confinement (United States)

    Malgaretti, P.; Pagonabarraga, I.; Rubi, J. M.


    We analyze the performance of a Brownian ratchet in the presence of geometrical constraints. A two-state model that describes the kinetics of molecular motors is used to characterize the energetic cost when the motor proceeds under confinement, in the presence of an external force. We show that the presence of geometrical constraints has a strong effect on the performance of the motor. In particular, we show that it is possible to enhance the ratchet performance by a proper tuning of the parameters characterizing the environment. These results open the possibility of engineering entropically-optimized transport devices.

  16. Hadrosynthesis and Quark Confinement

    Directory of Open Access Journals (Sweden)

    Satz Helmut


    Full Text Available Multihadron production in high energy collisions, from e+e− annihilation to heavy ion interactions, shows remarkable thermal behaviour, specified by a universal “Hagedorn” temperature. We argue that this hadronic radiation is formed by tunnelling through the event horizon of colour confinement, i.e., that it is the QCD counterpart of Hawking-Unruh radiation from black holes. It is shown to be emitted at a universal temperature TH ≃ (σ/2π1/2, where σ denotes the string tension. Since the event horizon does not allow information transfer, the radiation is thermal “at birth”.

  17. Confinement and 4-manifolds

    CERN Multimedia

    CERN. Geneva


    In this talk I will survey a connection between two very challenging problems, one in physics and one in math. The physics problem involves quantitative understanding of confinement in a system with least amount of supersymmetry that has been studied so far and that has a wide range of applications, from semi-realistic string models to qualitatively new examples of gauge-gravity duality. Surprisingly, the rich physics of this system translates into incredibly rich mathematics of the only remaining unsolved case of the Poincare conjecture.

  18. Confined compressive strength model of rock for drilling optimization

    Directory of Open Access Journals (Sweden)

    Xiangchao Shi


    Full Text Available The confined compressive strength (CCS plays a vital role in drilling optimization. On the basis of Jizba's experimental results, a new CCS model considering the effects of the porosity and nonlinear characteristics with increasing confining pressure has been developed. Because the confining pressure plays a fundamental role in determining the CCS of bottom-hole rock and because the theory of Terzaghi's effective stress principle is founded upon soil mechanics, which is not suitable for calculating the confining pressure in rock mechanics, the double effective stress theory, which treats the porosity as a weighting factor of the formation pore pressure, is adopted in this study. The new CCS model combined with the mechanical specific energy equation is employed to optimize the drilling parameters in two practical wells located in Sichuan basin, China, and the calculated results show that they can be used to identify the inefficient drilling situations of underbalanced drilling (UBD and overbalanced drilling (OBD.

  19. Polymer Conformation under Confinement

    Directory of Open Access Journals (Sweden)

    Stavros Bollas


    Full Text Available The conformation of polymer chains under confinement is investigated in intercalated polymer/layered silicate nanocomposites. Hydrophilic poly(ethylene oxide/sodium montmorillonite, PEO/Na+-MMT, hybrids were prepared utilizing melt intercalation with compositions where the polymer chains are mostly within the ~1 nm galleries of the inorganic material. The polymer chains are completely amorphous in all compositions even at temperatures where the bulk polymer is highly crystalline. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR is utilized to investigate the conformation of the polymer chains over a broad range of temperatures from below to much higher than the bulk polymer melting temperature. A systematic increase of the gauche conformation relatively to the trans is found with decreasing polymer content both for the C–C and the C–O bonds that exist along the PEO backbone indicating that the severe confinement and the proximity to the inorganic surfaces results in a more disordered state of the polymer.

  20. WaveNet (United States)


    Coastal Inlets Research Program WaveNet WaveNet is a web-based, Graphical-User-Interface ( GUI ) data management tool developed for Corps coastal...generates tabular and graphical information for project planning and design documents. The WaveNet is a web-based GUI designed to provide users with from different sources, and employs a combination of Fortran, Python and Matlab codes to process and analyze data for USACE applications

  1. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt


    This paper describes how Coloured Petri Nets (CP-nets) have been developed — from being a promising theoretical model to being a full-fledged language for the design, specification, simulation, validation and implementation of large software systems (and other systems in which human beings and...... use of CP-nets — because it means that the function representation and the translations (which are a bit mathematically complex) no longer are parts of the basic definition of CP-nets. Instead they are parts of the invariant method (which anyway demands considerable mathematical skills...

  2. Game Coloured Petri Nets

    DEFF Research Database (Denmark)

    Westergaard, Michael


    This paper introduces the notion of game coloured Petri nets. This allows the modeler to explicitly model what parts of the model comprise the modeled system and what parts are the environment of the modeled system. We give the formal definition of game coloured Petri nets, a means of reachability...... analysis of this net class, and an application of game coloured Petri nets to automatically generate easy-to-understand visualizations of the model by exploiting the knowledge that some parts of the model are not interesting from a visualization perspective (i.e. they are part of the environment...

  3. Programming NET Web Services

    CERN Document Server

    Ferrara, Alex


    Web services are poised to become a key technology for a wide range of Internet-enabled applications, spanning everything from straight B2B systems to mobile devices and proprietary in-house software. While there are several tools and platforms that can be used for building web services, developers are finding a powerful tool in Microsoft's .NET Framework and Visual Studio .NET. Designed from scratch to support the development of web services, the .NET Framework simplifies the process--programmers find that tasks that took an hour using the SOAP Toolkit take just minutes. Programming .NET

  4. Annotating Coloured Petri Nets

    DEFF Research Database (Denmark)

    Lindstrøm, Bo; Wells, Lisa Marie


    -net. An example of such auxiliary information is a counter which is associated with a token to be able to do performance analysis. Modifying colour sets and arc inscriptions in a CP-net to support a specific use may lead to creation of several slightly different CP-nets – only to support the different uses...... a method which makes it possible to associate auxiliary information, called annotations, with tokens without modifying the colour sets of the CP-net. Annotations are pieces of information that are not essential for determining the behaviour of the system being modelled, but are rather added to support...

  5. Heat stress of two tropical seagrass species during low tides - impact on underwater net photosynthesis, dark respiration and diel in situ internal aeration

    DEFF Research Database (Denmark)

    Pedersen, Ole; Colmer, Timothy D.; Borum, Jens


    Seagrasses grow submerged in aerated seawater but often in low O2 sediments. Elevated temperatures and low O2 are stress factors. Internal aeration was measured in two tropical seagrasses, Thalassia hemprichii and Enhalus acoroides, growing with extreme tides and diel temperature amplitudes......), the high temperatures and reduced CO2 would have diminished PN, whereas RD increased (Q10 of 2.0-2.7) above that at 33°C (0.45 and 0.33 μmol O2 m-2 s-1, respectively). During night-time low tides, O2 declined resulting in shoot base anoxia in both species, but incoming water containing c. 20 kPa O2...

  6. Using the quantum yields of photosystem II and the rate of net photosynthesis to monitor high irradiance and temperature stress in chrysanthemum (Dendranthema grandiflora)

    DEFF Research Database (Denmark)

    Wakjera, Eshetu Janka; Körner, Oliver; Rosenqvist, Eva


    Under a dynamic greenhouse climate control regime, temperature is adjusted to optimise plant physiological responses to prevailing irradiance levels; thus, both temperature and irradiance are used by the plant to maximise the rate of photosynthesis, assuming other factors are not limiting...... irradiance, the maximum Pn and ETR were reached at 24 °C. Increased irradiance decreased the PSII operating efficiency and increased NPQ, while both high irradiance and temperature had a significant effect on the PSII operating efficiency at temperatures >28 °C. Under high irradiance and temperature, changes...... in the NPQ determined the PSII operating efficiency, with no major change in the fraction of open PSII centres (qL) (indicating a QA redox state). We conclude that 1) chrysanthemum plants cope with excess irradiance by non-radiative dissipation or a reversible stress response, with the effect on the Pn...

  7. Velocity dependence of friction of confined polymers

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, V.N.; Persson, B.N.J.


    We present molecular dynamics friction calculations for confined hydrocarbon solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: (a) polymer sliding against a hard substrate, and (b) polymer sliding on polymer. We discuss the velocity dependence of the frictional...... shear stress for both cases. In our simulations, the polymer films are very thin (approx. 3 nm), and the solid walls are connected to a thermostat at a short distance from the polymer slab. Under these circumstances we find that frictional heating effects are not important, and the effective temperature...... in the polymer film is always close to the thermostat temperature. In the first setup (a), for hydrocarbons with molecular lengths from 60 to 1400 carbon atoms, the shear stresses are nearly independent of molecular length, but for the shortest hydrocarbon C20H42 the frictional shear stress is lower. In all...

  8. Net zero water

    CSIR Research Space (South Africa)

    Lindeque, M


    Full Text Available Is it possible to develop a building that uses a net zero amount of water? In recent years it has become evident that it is possible to have buildings that use a net zero amount of electricity. This is possible when the building is taken off...

  9. SolNet

    DEFF Research Database (Denmark)

    Jordan, Ulrike; Vajen, Klaus; Bales, Chris


    SolNet, founded in 2006, is the first coordinated International PhD education program on Solar Thermal Engineering. The SolNet network is coordinated by the Institute of Thermal Engineering at Kassel University, Germany. The network offers PhD courses on solar heating and cooling, conference...

  10. Kunstige neurale net

    DEFF Research Database (Denmark)

    Hørning, Annette


    Artiklen beskæftiger sig med muligheden for at anvende kunstige neurale net i forbindelse med datamatisk procession af naturligt sprog, specielt automatisk talegenkendelse.......Artiklen beskæftiger sig med muligheden for at anvende kunstige neurale net i forbindelse med datamatisk procession af naturligt sprog, specielt automatisk talegenkendelse....

  11. Degraded Confinement in Tokamak Experiments

    NARCIS (Netherlands)

    Schüller, F. C.


    After a review on the state of tokamak transport theory, the methodology to derive experimental results will be described. Examples of confinement in ohmic plasmas and the deterioration with additional heating will be given. Some examples of improved confinement modes will be discussed. Fluctuation

  12. Velocity Dependence of Friction of Confined Hydrocarbons

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, Vladimir N.; Persson, Bo N. J.


    We present molecular dynamics friction calculations for confined hydrocarbon “polymer” solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: (a) polymer sliding against a hard substrate and (b) polymer sliding on polymer. We discuss the velocity dependence of the f......We present molecular dynamics friction calculations for confined hydrocarbon “polymer” solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: (a) polymer sliding against a hard substrate and (b) polymer sliding on polymer. We discuss the velocity dependence...... of the frictional shear stress for both cases. In our simulations, the polymer films are very thin (∼3 nm), and the solid walls are connected to a thermostat at a short distance from the polymer slab. Under these circumstances we find that frictional heating effects are not important, and the effective temperature...... in the polymer film is always close to the thermostat temperature. In the first setup (a), for hydrocarbons with molecular lengths from 60 to 1400 carbon atoms, the shear stresses are nearly independent of molecular length, but for the shortest hydrocarbon C20H42 the frictional shear stress is lower. In all...

  13. Gravitationally confined relativistic neutrinos (United States)

    Vayenas, C. G.; Fokas, A. S.; Grigoriou, D.


    Combining special relativity, the equivalence principle, and Newton’s universal gravitational law with gravitational rather than rest masses, one finds that gravitational interactions between relativistic neutrinos with kinetic energies above 50 MeV are very strong and can lead to the formation of gravitationally confined composite structures with the mass and other properties of hadrons. One may model such structures by considering three neutrinos moving symmetrically on a circular orbit under the influence of their gravitational attraction, and by assuming quantization of their angular momentum, as in the Bohr model of the H atom. The model contains no adjustable parameters and its solution, using a neutrino rest mass of 0.05 eV/c2, leads to composite state radii close to 1 fm and composite state masses close to 1 GeV/c2. Similar models of relativistic rotating electron - neutrino pairs give a mass of 81 GeV/c2, close to that of W bosons. This novel mechanism of generating mass suggests that the Higgs mass generation mechanism can be modeled as a latent gravitational field which gets activated by relativistic neutrinos.

  14. Inertial confinement fusion

    Energy Technology Data Exchange (ETDEWEB)

    Powers, L.; Condouris, R.; Kotowski, M.; Murphy, P.W. (eds.)


    This issue of the ICF Quarterly contains seven articles that describe recent progress in Lawrence Livermore National Laboratory's ICF program. The Department of Energy recently initiated an effort to design a 1--2 MJ glass laser, the proposed National Ignition Facility (NIF). These articles span various aspects of a program which is aimed at moving forward toward such a facility by continuing to use the Nova laser to gain understanding of NIF-relevant target physics, by developing concepts for an NIF laser driver, and by envisioning a variety of applications for larger ICF facilities. This report discusses research on the following topics: Stimulated Rotational Raman Scattering in Nitrogen; A Maxwell Equation Solver in LASNEX for the Simulation of Moderately Intense Ultrashort Pulse Experiments; Measurements of Radial Heat-Wave Propagation in Laser-Produced Plasmas; Laser-Seeded Modulation Growth on Directly Driven Foils; Stimulated Raman Scattering in Large-Aperture, High-Fluence Frequency-Conversion Crystals; Fission Product Hazard Reduction Using Inertial Fusion Energy; Use of Inertial Confinement Fusion for Nuclear Weapons Effects Simulations.

  15. Effects of Predamaged Level on Confined HSC Columns

    Directory of Open Access Journals (Sweden)

    Ma Chau-Khun


    Full Text Available In the design of repair works for damaged concrete, an accurate and representative stress-strain model is of important. The stress-strain model for damaged high strength concrete (HSC repaired with post-tensioning steel straps confinement yet available, although the confining method has been proven to be effective in improving the performance of non-damaged HSC. A series of experimental test was carried out to investigate the stress-strain relationships of such concrete. A total of 24 HSC cylinders were compressed until certain damaged levels, then repaired by using steel straps. Two important parameters have been identified to have significant effects on the stress-strain relationship of such repaired concrete, namely the confining volumetric ratio and damaged levels. These parameters were incorporated into the development of stressstrain model, which later was shown to correlate well with the experimental results. This paper also has evidenced that existing stressstrain models of damaged concrete are not suitable to be directly applied to the design of repair works using post-tensioning steel straps confinement that produce external lateral stress on damaged columns before subsequent loading applied.

  16. Pro NET Best Practices

    CERN Document Server

    Ritchie, Stephen D


    Pro .NET Best Practices is a practical reference to the best practices that you can apply to your .NET projects today. You will learn standards, techniques, and conventions that are sharply focused, realistic and helpful for achieving results, steering clear of unproven, idealistic, and impractical recommendations. Pro .NET Best Practices covers a broad range of practices and principles that development experts agree are the right ways to develop software, which includes continuous integration, automated testing, automated deployment, and code analysis. Whether the solution is from a free and

  17. Getting to Net Zero

    Energy Technology Data Exchange (ETDEWEB)


    The technology necessary to build net zero energy buildings (NZEBs) is ready and available today, however, building to net zero energy performance levels can be challenging. Energy efficiency measures, onsite energy generation resources, load matching and grid interaction, climatic factors, and local policies vary from location to location and require unique methods of constructing NZEBs. It is recommended that Components start looking into how to construct and operate NZEBs now as there is a learning curve to net zero construction and FY 2020 is just around the corner.

  18. Instant Lucene.NET

    CERN Document Server

    Heydt, Michael


    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. A step-by-step guide that helps you to index, search, and retrieve unstructured data with the help of Lucene.NET.Instant Lucene.NET How-to is essential for developers new to Lucene and Lucene.NET who are looking to get an immediate foundational understanding of how to use the library in their application. It's assumed you have programming experience in C# already, but not that you have experience with search techniques such as information retrieval theory (although there will be a l

  19. Design of the Violence and Stress Assessment (ViStA) study: a randomized controlled trial of care management for PTSD among predominantly Latino patients in safety net health centers. (United States)

    Meredith, Lisa S; Eisenman, David P; Green, Bonnie L; Kaltman, Stacey; Wong, Eunice C; Han, Bing; Cassells, Andrea; Tobin, Jonathan N


    Posttraumatic stress disorder (PTSD) is a common problem in primary care. Although effective treatments are available, little is known about whether such treatments are effective within the context of Federally Qualified Health Centers (FQHCs) that serve as national "safety nets" for providing primary care for low income and underinsured patients. The Violence and Stress Assessment (ViStA) study is the first randomized controlled trial (RCT) to test the impact of a care management intervention for treating PTSD in FQHCs. To develop a PTSD management intervention appropriate for lower resource FQHCs and the predominantly Latino patients they serve, formative work was conducted through a collaborative effort between researchers and an FQHC practice-based research network. This article describes how FQHC stakeholders were convened to review, assess, and prioritize evidence-based strategies for addressing patient, clinician, and system-level barriers to care. This multi-component care management intervention incorporates diagnosis with feedback, patient education and activation; navigation and linkage to community resources; clinician education and medication guidance; and structured cross-disciplinary communication and continuity of care, all facilitated by care managers with FQHC experience. We also describe the evaluation design of this five-year RCT and the characteristics of the 404 English or Spanish speaking patients enrolled in the study and randomized to either the intervention or to usual care. Patients are assessed at baseline, six months, and 12 months to examine intervention effectiveness on PTSD, other mental health symptoms, health-related quality-of-life, health care service use; and perceived barriers to care and satisfaction with care. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. High-Energy Electron Confinement in a Magnetic Cusp Configuration

    Directory of Open Access Journals (Sweden)

    Jaeyoung Park


    Full Text Available We report experimental results validating the concept that plasma confinement is enhanced in a magnetic cusp configuration when β (plasma pressure/magnetic field pressure is of order unity. This enhancement is required for a fusion power reactor based on cusp confinement to be feasible. The magnetic cusp configuration possesses a critical advantage: the plasma is stable to large scale perturbations. However, early work indicated that plasma loss rates in a reactor based on a cusp configuration were too large for net power production. Grad and others theorized that at high β a sharp boundary would form between the plasma and the magnetic field, leading to substantially smaller loss rates. While not able to confirm the details of Grad’s work, the current experiment does validate, for the first time, the conjecture that confinement is substantially improved at high β. This represents critical progress toward an understanding of the plasma dynamics in a high-β cusp system. We hope that these results will stimulate a renewed interest in the cusp configuration as a fusion confinement candidate. In addition, the enhanced high-energy electron confinement resolves a key impediment to progress of the Polywell fusion concept, which combines a high-β cusp configuration with electrostatic fusion for a compact, power-producing nuclear fusion reactor.

  1. Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Bourrelle, Julien S.; Musall, Eike


    and identify possible renewable energy supply options which may be considered in calculations. Finally, the gap between the methodology proposed by each organisation and their respective national building code is assessed; providing an overview of the possible changes building codes will need to undergo......The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...... parameters used in the calculations are discussed and the various renewable supply options considered in the methodologies are summarised graphically. Thus, the paper helps to understand different existing approaches to calculate energy balance in Net ZEBs, highlights the importance of variables selection...

  2. PhysioNet (United States)

    U.S. Department of Health & Human Services — The PhysioNet Resource is intended to stimulate current research and new investigations in the study of complex biomedical and physiologic signals. It offers free...

  3. NetSig

    DEFF Research Database (Denmark)

    Horn, Heiko; Lawrence, Michael S; Chouinard, Candace R


    Methods that integrate molecular network information and tumor genome data could complement gene-based statistical tests to identify likely new cancer genes; but such approaches are challenging to validate at scale, and their predictive value remains unclear. We developed a robust statistic (Net......Sig) that integrates protein interaction networks with data from 4,742 tumor exomes. NetSig can accurately classify known driver genes in 60% of tested tumor types and predicts 62 new driver candidates. Using a quantitative experimental framework to determine in vivo tumorigenic potential in mice, we found that Net......Sig candidates induce tumors at rates that are comparable to those of known oncogenes and are ten-fold higher than those of random genes. By reanalyzing nine tumor-inducing NetSig candidates in 242 patients with oncogene-negative lung adenocarcinomas, we find that two (AKT2 and TFDP2) are significantly amplified...

  4. TideNet (United States)


    query tide data sources in a desired geographic region of USA and its territories (Figure 1). Users can select a tide data source through the Google Map data sources according to the desired geographic region. It uses the Google Map interface to display data from different sources. Recent...Coastal Inlets Research Program TideNet The TideNet is a web-based Graphical User Interface (GUI) that provides users with GIS mapping tools to

  5. Building Neural Net Software


    Neto, João Pedro; Costa, José Félix


    In a recent paper [Neto et al. 97] we showed that programming languages can be translated on recurrent (analog, rational weighted) neural nets. The goal was not efficiency but simplicity. Indeed we used a number-theoretic approach to machine programming, where (integer) numbers were coded in a unary fashion, introducing a exponential slow down in the computations, with respect to a two-symbol tape Turing machine. Implementation of programming languages in neural nets turns to be not only theo...

  6. Interaction Nets in Russian


    Salikhmetov, Anton


    Draft translation to Russian of Chapter 7, Interaction-Based Models of Computation, from Models of Computation: An Introduction to Computability Theory by Maribel Fernandez. "In this chapter, we study interaction nets, a model of computation that can be seen as a representative of a class of models based on the notion of 'computation as interaction'. Interaction nets are a graphical model of computation devised by Yves Lafont in 1990 as a generalisation of the proof structures of linear logic...

  7. Programming NET 35

    CERN Document Server

    Liberty, Jesse


    Bestselling author Jesse Liberty and industry expert Alex Horovitz uncover the common threads that unite the .NET 3.5 technologies, so you can benefit from the best practices and architectural patterns baked into the new Microsoft frameworks. The book offers a Grand Tour" of .NET 3.5 that describes how the principal technologies can be used together, with Ajax, to build modern n-tier and service-oriented applications. "

  8. Stress

    DEFF Research Database (Denmark)

    Keller, Hanne Dauer


    Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb.......Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb....

  9. Confining Strings with Topological Term

    CERN Document Server

    Diamantini, M Cristina; Trugenberger, Carlo Andrea


    We consider several aspects of `confining strings', recently proposed to describe the confining phase of gauge field theories. We perform the exact duality transformation that leads to the confining string action and show that it reduces to the Polyakov action in the semiclassical approximation. In 4D we introduce a `$\\theta$-term' and compute the low-energy effective action for the confining string in a derivative expansion. We find that the coefficient of the extrinsic curvature (stiffness) is negative, confirming previous proposals. In the absence of a $\\theta$-term, the effective string action is only a cut-off theory for finite values of the coupling e, whereas for generic values of $\\theta$, the action can be renormalized and to leading order we obtain the Nambu-Goto action plus a topological `spin' term that could stabilize the system.

  10. Alternative approaches to plasma confinement (United States)

    Roth, J. R.


    The paper discusses 20 plasma confinement schemes each representing an alternative to the tokamak fusion reactor. Attention is given to: (1) tokamak-like devices (TORMAC, Topolotron, and the Extrap concept), (2) stellarator-like devices (Torsatron and twisted-coil stellarators), (3) mirror machines (Astron and reversed-field devices, the 2XII B experiment, laser-heated solenoids, the LITE experiment, the Kaktus-Surmac concept), (4) bumpy tori (hot electron bumpy torus, toroidal minimum-B configurations), (5) electrostatically assisted confinement (electrostatically stuffed cusps and mirrors, electrostatically assisted toroidal confinement), (6) the Migma concept, and (7) wall-confined plasmas. The plasma parameters of the devices are presented and the advantages and disadvantages of each are listed.

  11. Impurities confined in quantum structures

    CERN Document Server

    Holtz, Per Olof


    The introduction of impurities, even in very small concentrations, in a semiconductor can change its optical and electrical properties entirely. This attribute of the semiconductor is utilized in the manifoldness of their applications. In this book, the progress on elucidating the physical properties of impurities confined in quantum structures are reviewed with an emphasis on the experimental aspects. The major results of various kinds of characterization, such as infrared spectroscopy, Raman measurements, luminescence characterization, perturbation spectroscopy and dynamical studies of the confined impurities are reviewed, but also the theoretical basis to calculate the electronic structure of the confined donors and acceptors are presented. This monograph also describes more specific aspects of the confined impurities such as the properties in the high doping regime and the effects of hydrogen passivation.

  12. Multiple-scale turbulence model in confined swirling jet predictions (United States)

    Chen, C. P.


    A recently developed multiple-scale turbulence model which attempts to circumvent the deficiencies of earlier models by taking nonequilibrium spectral energy transfer into account is presented. The model's validity is tested by predicting the confined swirling coaxial jet flow in a sudden expansion. It is noted that, in order to account for anisotropic turbulence, a full Reynolds stress model is required.

  13. Numerical study of high-strength concrete column confined with high-strength stirrups under axial compression (United States)

    Liu, Qinwei; Wang, Nan; Niu, Xin; Cai, Zhe; Wang, Gang


    In order to study the deformation and stress distribution of confined concrete, the axial compression behavior of high-strength concrete column confined with high-strength stirrups is simulated through through nonlinear finite element program. The finite element model reflect the confining effect of high-strength stirrups in specimen. The calculated results shown that the deformation of stirrups is not equivalent in the cross section and the longitudinal section and the confined stress and axial stress of concrete is not uniform in the cross section.

  14. Aerofractures in Confined Granular Media (United States)

    Eriksen, Fredrik K.; Turkaya, Semih; Toussaint, Renaud; Måløy, Knut J.; Flekkøy, Eirik G.


    We will present the optical analysis of experimental aerofractures in confined granular media. The study of this generic process may have applications in industries involving hydraulic fracturing of tight rocks, safe construction of dams, tunnels and mines, and in earth science where phenomena such as mud volcanoes and sand injectites are results of subsurface sediment displacements driven by fluid overpressure. It is also interesting to increase the understanding the flow instability itself, and how the fluid flow impacts the solid surrounding fractures and in the rest of the sample. Such processes where previously studied numerically [Niebling 2012a, Niebling 2012b] or in circular geometries. We will here explore experimentally linear geometries. We study the fracturing patterns that form when air flows into a dense, non-cohesive porous medium confined in a Hele-Shaw cell - i.e. into a packing of dry 80 micron beads placed between two glass plates separated by ~1mm. The cell is rectangular and fitted with a semi-permeable boundary to the atmosphere - blocking beads but not air - on one short edge, while the other three edges are impermeable. The porous medium is packed inside the cell between the semi-permeable boundary and an empty volume at the sealed side where the air pressure can be set and kept at a constant overpressure (1-2bar). Thus, for the air trapped inside the cell to release the overpressure it has to move through the solid. At high enough overpressures the air flow deforms the solid and increase permeability in some regions along the air-solid interface, which results in unstable flow and aerofracturing. Aerofractures are thought to be an analogue to hydrofractures, and an advantage of performing aerofracturing experiments in a Hele-Shaw cell is that the fracturing process can easily be observed in the lab. Our experiments are recorded with a high speed camera with a framerate of 1000 frames per second. In the analysis, by using various image

  15. Reatividade animal Confinement reactivity

    Directory of Open Access Journals (Sweden)

    Walsiara Estanislau Maffei


    Full Text Available A reatividade é definida como a reação do animal quando contido num ambiente de contenção móvel. Ela é quantificada por meio do teste de reatividade animal em ambiente de contenção móvel - REATEST®. Este teste consiste num dispositivo eletrônico acoplado à balança e num software específico. O dispositivo capta a movimentação que o animal provoca na balança, durante 20 segundos e a envia para o software que a processa determinando a reatividade do animal numa escala contínua de pontos. Pontuações maiores são de animais mais reativos (mais agressivo. A reatividade foi criada com os objetivos de solucionar os problemas até então existentes na seleção para temperamento e de permitir estimação de parâmetros genéticos mais confiáveis. Ela é uma característica objetiva que tem grande variabilidade fenotípica e é de quantificação rápida, fácil e segura, além de poder ser quantificada em qualquer tipo de balança, o que permite maior aplicabilidade. Ela não interfere nas práticas de manejo das fazendas porque é quantificada no momento da pesagem dos animais. Sua herdabilidade na raça Nelore é de 0,39 ao ano e 0,23 ao sobreano e suas correlações genéticas com ganho de peso diário são de -0,28 do nascimento até desmama e de -0,49 do desmame até ano. Já suas correlações genéticas com desenvolvimento do perímetro escrotal do ano ao sobreano variam de -0,25 e -0,41.The confinement reactivity (CR has been used as a measure of temperament in Brazil and it is defined as the animal reaction when contained in the scale. It is quantified through the animal reactivity test - REATEST®. This test consists of an electronic device coupled to the scale and of specific software. The device captures the movement that the animal provokes in the scale, during 20 seconds and sends it for the software that processes this movement and determines the animal CR in a continuous scale of points. Higher punctuations belong to

  16. PREFACE: Water in confined geometries (United States)

    Rovere, Mauro


    The study of water confined in complex systems in solid or gel phases and/or in contact with macromolecules is relevant to many important processes ranging from industrial applications such as catalysis and soil chemistry, to biological processes such as protein folding or ionic transport in membranes. Thermodynamics, phase behaviour and the molecular mobility of water have been observed to change upon confinement depending on the properties of the substrate. In particular, polar substrates perturb the hydrogen bond network of water, inducing large changes in the properties upon freezing. Understanding how the connected random hydrogen bond network of bulk water is modified when water is confined in small cavities inside a substrate material is very important for studies of stability and the enzymatic activity of proteins, oil recovery or heterogeneous catalysis, where water-substrate interactions play a fundamental role. The modifications of the short-range order in the liquid depend on the nature of the water-substrate interaction, hydrophilic or hydrophobic, as well as on its spatial range and on the geometry of the substrate. Despite extensive study, both experimentally and by computer simulation, there remain a number of open problems. In the many experimental studies of confined water, those performed on water in Vycor are of particular interest for computer simulation and theoretical studies since Vycor is a porous silica glass characterized by a quite sharp distribution of pore sizes and a strong capability to absorb water. It can be considered as a good candidate for studying the general behaviour of water in hydrophilic nanopores. But there there have been a number of studies of water confined in more complex substrates, where the interpretation of experiments and computer simulation is more difficult, such as in zeolites or in aerogels or in contact with membranes. Of the many problems to consider we can mention the study of supercooled water. It is

  17. Stress


    Jensen, Line Skov; Lova, Lotte; Hansen, Zandra Kulikovsky; Schønemann, Emilie; Larsen, Line Lyngby; Colberg Olsen, Maria Sophia; Juhl, Nadja; Magnussen, Bogi Roin


    Stress er en tilstand som er meget omdiskuteret i samfundet, og dette besværliggør i en vis grad konkretiseringen af mulige løsningsforslag i bestræbelsen på at forebygge den såkaldte folkesygdom. Hovedkonklusionen er, at selv om der bliver gjort meget for at forebygge, er der ikke meget der aktivt kan sættes i værk for at reducere antallet af stressramte, før en fælles forståelse af stressårsager og effektiv stresshåndtering er fremlagt. Problemformuleringen er besvaret gennem en undersø...

  18. La plataforma .NET


    Fornas Estrada, Miquel


    L'aparició de la plataforma .NET Framework ha suposat un canvi molt important en la forma de crear i distribuir aplicacions, degut a que incorpora una sèrie d'innovacions tècniques i productives que simplifiquen molt les tasques necessàries per desenvolupar un projecte. La aparición de la plataforma. NET Framework ha supuesto un cambio muy importante en la forma de crear y distribuir aplicaciones, debido a que incorpora una serie de innovaciones técnicas y productivas que simplifican mucho...

  19. Biological Petri Nets

    CERN Document Server

    Wingender, E


    It was suggested some years ago that Petri nets might be well suited to modeling metabolic networks, overcoming some of the limitations encountered by the use of systems employing ODEs (ordinary differential equations). Much work has been done since then which confirms this and demonstrates the usefulness of this concept for systems biology. Petri net technology is not only intuitively understood by scientists trained in the life sciences, it also has a robust mathematical foundation and provides the required degree of flexibility. As a result it appears to be a very promising approach to mode

  20. Sandpile model with tokamaklike enhanced confinement phenomenology. (United States)

    Chapman, S C; Dendy, R O; Hnat, B


    Confinement phenomenology characteristic of magnetically confined plasmas emerges naturally from a simple sandpile algorithm when the parameter controlling redistribution scale length is varied. Close analogs are found for enhanced confinement, edge pedestals, and edge localized modes (ELMs), and for the qualitative correlations between them. These results suggest that tokamak observations of avalanching transport are deeply linked to the existence of enhanced confinement and ELMs.

  1. Confinement-deconfinement transitions in a model of interacting dislocations (United States)

    Balakrishnan, V.; Bottani, C. E.


    An exact solution is found for the equilibrium dislocation distribution in a continuum model of interacting parallel dislocations moving in a common slip plane, under an external shear σ and a realistic internal stress barrier that is finite everywhere on the slip plane. As functions of σ and the total populations, we find regions of two-component confinement (a compact distribution of dislocations of both signs), stable single-component confinement, and breakaway. Stability properties are summarized and critical lines on the bifurcation surface are identified.

  2. Petri Nets-Applications

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 9. Petri Nets - Applications. Y Narahari. General Article Volume 4 Issue 9 September 1999 pp 44-52. Fulltext. Click here to view fulltext PDF. Permanent link: Author Affiliations. Y Narahari ...

  3. Safety nets or straitjackets?

    DEFF Research Database (Denmark)

    Ilsøe, Anna


    Does regulation of working hours at national and sector level impose straitjackets, or offer safety nets to employees seeking working time flexibility? This article compares legislation and collective agreements in the metal industries of Denmark, Germany and the USA. The industry has historically...

  4. Coloured Petri Nets

    CERN Document Server

    Jensen, Kurt


    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. This book introduces the constructs of the CPN modelling language and presents the related analysis methods. It provides a comprehensive road map for the practical use of CPN.

  5. Boom Booom Net Radio

    DEFF Research Database (Denmark)

    Grimshaw, Mark Nicholas; Yong, Louisa; Dobie, Ian


    of an existing Internet radio station; Boom Booom Net Radio. Whilst necessity dictates some use of technology-related terminology, wherever possible we have endeavoured to keep such jargon to a minimum and to either explain it in the text or to provide further explanation in the appended glossary....

  6. Game Theory .net. (United States)

    Shor, Mikhael


    States making game theory relevant and accessible to students is challenging. Describes the primary goal of is to provide interactive teaching tools. Indicates the site strives to unite educators from economics, political and computer science, and ecology by providing a repository of lecture notes and tests for courses using…

  7. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kristensen, Lars Michael

    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. The development of such systems is particularly challenging because of inherent intricacies like possible nondeterminism...


    Energy Technology Data Exchange (ETDEWEB)



    This is the final report for the project 'Correlations in Confined Quantum Plasmas', NSF-DOE Partnership Grant DE FG02 07ER54946, 8/1/2007 - 7/30/2010. The research was performed in collaboration with a group at Christian Albrechts University (CAU), Kiel, Germany. That collaboration, almost 15 years old, was formalized during the past four years under this NSF-DOE Partnership Grant to support graduate students at the two institutions and to facilitate frequent exchange visits. The research was focused on exploring the frontiers of charged particle physics evolving from new experimental access to unusual states associated with confinement. Particular attention was paid to combined effects of quantum mechanics and confinement. A suite of analytical and numerical tools tailored to the specific inquiry has been developed and employed

  9. Knotted DNA in Nanofluidic Confinement (United States)

    Klotz, Alexander; Doyle, Patrick

    The behavior of topologically simple semiflexible polymers such as DNA has become well-understood in the last several years. Recently, several computational analyses have predicted that certain topological features of a polymer, such as the average size of pseudo-knots and the probability of knot formation, are enhanced by confinement. Here, we extend recent work on the stretching of knotted DNA and examine diffusion, relaxation, and chain statistics of topologically complex linear DNA molecules. Topological phenomena are studied both in the bulk and under nanofluidic confinement to examine the interplay between knotting and confinement in semiflexible polymers, as well as to provide a controlled experimental interrogation of the knotted region of the polymer.

  10. Calculation of confined swirling jets (United States)

    Chen, C. P.


    Computations of a confined coaxial swirling jet are carried out using a standard two-equation (k-epsilon) model and two modifications of this model based on Richardson-number corrections of the length-scale (epsilon) governing equation. To avoid any uncertainty involved in the setting up of inlet boundary conditions, actual measurements are used at the inlet plane of this calculation domain. The results of the numerical investigation indicate that the k-epsilon model is inadequate for the predictions of confined swirling flows. Although marginal improvement of the flow predictions can be achieved by these two corrections, neither can be judged satisfactory.

  11. Analysis of Reinforced Concrete Hollow Piers Behavior: Benefits of FRP Confinement

    Directory of Open Access Journals (Sweden)

    Gian Piero Lignola


    Full Text Available Reliable stress-strain behavior of concrete is necessary particularly when a member is subjected to combine bending and axial load and confinement effects should be accounted for. A unified theory for confinement of circular hollow sections is proposed herein, that can be extended to the case of solid and noncircular sections. The main aim of the model is to trace step-by-step the evolution of the three dimensional stresses in confined concrete and confining devices (i.e. FRP externally bonded jackets. The iterative model is able to estimate confinement effectiveness and to plot stress-strain relationships, which are different in the case of solid and hollow sections. Through the proposed improved model, a simplified closed form solution has been also derived to directly determine ultimate confined concrete properties and stress-strain curves. At present, theoretical results based on the proposed concrete circular hollow sections confinement model, in satisfactory agreement with the experimental data available in scientific literature, show that FRP jacketing can enhance the ultimate load and ductility significantly, also in the case of hollow concrete cross sections.

  12. Turbulent jet in confined counterflow

    Indian Academy of Sciences (India)

    The mean flowfield of a turbulent jet issuing into a confined, uniform counterflow was investigated computationally. Based on dimensional analysis, the jet penetration length was shown to scale with jet-to-counterflow momentum flux ratio. This scaling and the computational results reproduce the well-known correct limit of ...

  13. Turbulent jet in confined counterflow

    Indian Academy of Sciences (India)

    Abstract. The mean flowfield of a turbulent jet issuing into a confined, uniform counterflow was investigated computationally. Based on dimensional analysis, the jet penetration length was shown to scale with jet-to-counterflow momentum flux ratio. This scaling and the computational results reproduce the well-known correct ...

  14. Effective viscosity of confined hydrocarbons

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, V.N.; Persson, B.N.J.


    We present molecular dynamics friction calculations for confined hydrocarbon films with molecular lengths from 20 to 1400 carbon atoms. We find that the logarithm of the effective viscosity ηeff for nanometer-thin films depends linearly on the logarithm of the shear rate: log ηeff=C-nlog γ̇, where...

  15. Unstable vortices do not confine

    NARCIS (Netherlands)

    Achúcarro, A.; Roo, M. de; Huiszoon, L.; Landshoff, P.V.


    Recently, a geometric model for the confinement of magnetic charges in the context of type II string compactifications was constructed. This model assumes the existence of stable magnetic vortices with quantized flux in the low energy theory. However, quantization of flux alone does not imply that

  16. Two flavor QCD and Confinement

    DEFF Research Database (Denmark)

    D'Elia, M.; Di Giacomo, A.; Pica, Claudio


    We argue that the order of the chiral transition for N_f=2 is a sensitive probe of the QCD vacuum, in particular of the mechanism of color confinement. A strategy is developed to investigate the order of the transition by use of finite size scaling analysis. An in-depth numerical investigation...

  17. Food Safety Nets:


    Haggblade, Steven; Diallo, Boubacar; Staatz, John; Theriault, Veronique; Traoré, Abdramane


    Food and social safety nets have a history as long as human civilization. In hunter gatherer societies, food sharing is pervasive. Group members who prove unlucky in the short run, hunting or foraging, receive food from other households in anticipation of reciprocal consideration at a later time (Smith 1988). With the emergence of the first large sedentary civilizations in the Middle East, administrative systems developed specifically around food storage and distribution. The ancient Egyptian...

  18. Net technical assessment


    Wegmann, David G.


    Approved for public release; distribution is unlimited. The present and near term military balance of power between the U.S. and the Soviet Union can be expressed in a variety of net assessments. One can examine the strategic nuclear balance, the conventional balance in Europe, the maritime balance, and many others. Such assessments are essential not only for policy making but for arms control purposes and future force structure planning. However, to project the future military balance, on...

  19. Stress. (United States)

    Chambers, David W


    We all experience stress as a regular, and sometimes damaging and sometimes useful, part of our daily lives. In our normal ups and downs, we have our share of exhaustion, despondency, and outrage--matched with their corresponding positive moods. But burnout and workaholism are different. They are chronic, dysfunctional, self-reinforcing, life-shortening habits. Dentists, nurses, teachers, ministers, social workers, and entertainers are especially susceptible to burnout; not because they are hard-working professionals (they tend to be), but because they are caring perfectionists who share control for the success of what they do with others and perform under the scrutiny of their colleagues (they tend to). Workaholics are also trapped in self-sealing cycles, but the elements are ever-receding visions of control and using constant activity as a barrier against facing reality. This essay explores the symptoms, mechanisms, causes, and successful coping strategies for burnout and workaholism. It also takes a look at the general stress response on the physiological level and at some of the damage American society inflicts on itself.

  20. Using WordNet for Building WordNets

    CERN Document Server

    Farreres, X; Farreres, Xavier; Rodriguez, Horacio; Rigau, German


    This paper summarises a set of methodologies and techniques for the fast construction of multilingual WordNets. The English WordNet is used in this approach as a backbone for Catalan and Spanish WordNets and as a lexical knowledge resource for several subtasks.

  1. Social stress modulates the cortisol response to an acute stressor in rainbow trout (Oncorhynchus mykiss). (United States)

    Jeffrey, J D; Gollock, M J; Gilmour, K M


    In rainbow trout (Oncorhynchus mykiss) of subordinate social status, circulating cortisol concentrations were elevated under resting conditions but the plasma cortisol and glucose responses to an acute stressor (confinement in a net) were attenuated relative to those of dominant trout. An in vitro head kidney preparation, and analysis of the expression of key genes in the stress axis prior to and following confinement in a net were then used to examine the mechanisms underlying suppression of the acute cortisol stress response in trout experiencing chronic social stress. With porcine adrenocorticotropic hormone (ACTH) as the secretagogue, ACTH-stimulated cortisol production was significantly lower for head kidney preparations from subordinate trout than for those from dominant trout. Dominant and subordinate fish did not, however, differ in the relative mRNA abundance of melanocortin-2 receptor (MC2R), steroidogenic acute regulatory protein (StAR) or cytochrome P450 side chain cleavage enzyme (P450scc) within the head kidney, although the relative mRNA abundance of these genes was significantly higher in both dominant and subordinate fish than in sham trout (trout that did not experience social interactions but were otherwise treated identically to the dominant and subordinate fish). The relative mRNA abundance of all three genes was significantly higher in trout exposed to an acute net stressor than under control conditions. Upstream of cortisol production in the stress axis, plasma ACTH concentrations were not affected by social stress, nor was the relative mRNA abundance of the binding protein for corticotropin releasing factor (CRF-BP). The relative mRNA abundance of CRF in the pre-optic area of subordinate fish was significantly higher than that of dominant or sham fish 1h after exposure to the stressor. Collectively, the results indicate that chronic social stress modulates cortisol production at the level of the interrenal cells, resulting in an attenuated

  2. Proof nets for lingusitic analysis

    NARCIS (Netherlands)

    Moot, R.C.A.


    This book investigates the possible linguistic applications of proof nets, redundancy free representations of proofs, which were introduced by Girard for linear logic. We will adapt the notion of proof net to allow the formulation of a proof net calculus which is soundand complete for the

  3. Teaching Tennis for Net Success. (United States)

    Young, Bryce


    A program for teaching tennis to beginners, NET (Net Easy Teaching) is described. The program addresses three common needs shared by tennis students: active involvement in hitting the ball, clearing the net, and positive reinforcement. A sample lesson plan is included. (IAH)

  4. Net4Care Ecosystem Website

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak; Hansen, Klaus Marius; Rasmussen, Morten


    is a tele-monitoring scenario in which Net4Care clients are deployed in a gateway in private homes. Medical devices then connect to these gateways and transmit their observations to a Net4Care server. In turn the Net4Care server creates valid clinical HL7 documents, stores them in a national XDS repository...

  5. Physics of magnetic confinement fusion

    Directory of Open Access Journals (Sweden)

    Wagner F.


    Full Text Available Fusion is the energy source of the universe. The local conditions in the core of the Sun allow the transfer of mass into energy, which is finally released in the form of radiation. Technical fusion melts deuterons and tritons to helium releasing large amounts of energy per fusion process. Because of the conditions for fusion, which will be deduced, the fusion fuel is in the plasma state. Here we report on the confinement of fusion plasmas by magnetic fields. Different confinement concepts — tokamaks and stellarators — will be introduced and described. The first fusion reactor, ITER, and the most modern stellarator, Wendelstein 7-X, are under construction. Their basic features and objectives will be presented.

  6. Master Robotic Net

    Directory of Open Access Journals (Sweden)

    Vladimir Lipunov


    Full Text Available The main goal of the MASTER-Net project is to produce a unique fast sky survey with all sky observed over a single night down to a limiting magnitude of 19-20. Such a survey will make it possible to address a number of fundamental problems: search for dark energy via the discovery and photometry of supernovae (including SNIa, search for exoplanets, microlensing effects, discovery of minor bodies in the Solar System, and space-junk monitoring. All MASTER telescopes can be guided by alerts, and we plan to observe prompt optical emission from gamma-ray bursts synchronously in several filters and in several polarization planes.

  7. Art/Net/Work

    DEFF Research Database (Denmark)

    Andersen, Christian Ulrik; Lindstrøm, Hanne


    The seminar Art|Net|Work deals with two important changes in our culture. On one side, the network has become essential in the latest technological development. The Internet has entered a new phase, Web 2.0, including the occurrence of as ‘Wiki’s’, ‘Peer-2-Peer’ distribution, user controlled...... the praxis of the artist. We see different kinds of interventions and activism (including ‘hacktivism’) using the network as a way of questioning the invisible rules that govern public and semi-public spaces. Who ‘owns’ them? What kind of social relationships do they generate? On what principle...

  8. Confinement of color and geometry

    CERN Document Server

    Di Giacomo, A


    A natural explanation of confinement can be given in terms of symmetry. Since color symmetry is exact, the candidate symmetry is dual and related to homotopy,i.e., in (3+1)d, to magnetic charge conservation. A set of r abelian 'tHooft-like tensors (r = rank of the gauge group) can be defined and the dual charge is a violation of the corresponding Bianchi identities. It is shown that this is equivalently described by non-abelian Bianchi identities.

  9. expansions to and an introduction to (United States)

    Martin, John; Rosa, Bruce A.; Ozersky, Philip; Hallsworth-Pepin, Kymberlie; Zhang, Xu; Bhonagiri-Palsikar, Veena; Tyagi, Rahul; Wang, Qi; Choi, Young-Jun; Gao, Xin; McNulty, Samantha N.; Brindley, Paul J.; Mitreva, Makedonka

    2015-01-01 ( is the new moniker for a collection of databases: and Within this collection we provide services and resources for parasitic roundworms (nematodes) and flatworms (trematodes), collectively known as helminths. For over a decade we have provided resources for studying nematodes via our veteran site ( In this article, (i) we provide an update on the expansions of that hosts omics data from 84 species and provides advanced search tools to the broad scientific community so that data can be mined in a useful and user-friendly manner and (ii) we introduce, a site dedicated to the dissemination of data from flukes, flatworm parasites of the class Trematoda, phylum Platyhelminthes. is an independent component of and currently hosts data from 16 species, with information ranging from genomic, functional genomic data, enzymatic pathway utilization to microbiome changes associated with helminth infections. The databases’ interface, with a sophisticated query engine as a backbone, is intended to allow users to search for multi-factorial combinations of species’ omics properties. This report describes updates to since its last description in NAR, 2012, and also introduces and presents its new sibling site, PMID:25392426


    Directory of Open Access Journals (Sweden)

    Evelia Schettini


    Full Text Available The aim of this paper was to investigate the radiometric properties of coloured nets used to protect a peach cultivation. The modifications of the solar spectral distribution, mainly in the R and FR wavelength band, influence plant photomorphogenesis by means of the phytochrome and cryptochrome. The phytochrome response is characterized in terms of radiation rate in the red wavelengths (R, 600-700 nm to that in the farred radiation (FR, 700-800 nm, i.e. the R/FR ratio. The effects of the blue radiation (B, 400-500 nm is investigated by the ratio between the blue radiation and the far-red radiation, i.e. the B/FR ratio. A BLUE net, a RED net, a YELLOW net, a PEARL net, a GREY net and a NEUTRAL net were tested in Bari (Italy, latitude 41° 05’ N. Peach trees were located in pots inside the greenhouses and in open field. The growth of the trees cultivated in open field was lower in comparison to the growth of the trees grown under the nets. The RED, PEARL, YELLOW and GREY nets increased the growth of the trees more than the other nets. The nets positively influenced the fruit characteristics, such as fruit weight and flesh firmness.

  11. The equivalency between logic Petri workflow nets and workflow nets. (United States)

    Wang, Jing; Yu, ShuXia; Du, YuYue


    Logic Petri nets (LPNs) can describe and analyze batch processing functions and passing value indeterminacy in cooperative systems. Logic Petri workflow nets (LPWNs) are proposed based on LPNs in this paper. Process mining is regarded as an important bridge between modeling and analysis of data mining and business process. Workflow nets (WF-nets) are the extension to Petri nets (PNs), and have successfully been used to process mining. Some shortcomings cannot be avoided in process mining, such as duplicate tasks, invisible tasks, and the noise of logs. The online shop in electronic commerce in this paper is modeled to prove the equivalence between LPWNs and WF-nets, and advantages of LPWNs are presented.

  12. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kristensen, Lars Michael

    studies that illustrate the practical use of CPN modelling and validation for design, specification, simulation, verification and implementation in various application domains. Their presentation primarily aims at readers interested in the practical use of CPN. Thus all concepts and constructs are first......Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. The development of such systems is particularly challenging because of inherent intricacies like possible nondeterminism...... and the immense number of possible execution sequences. In this textbook, Jensen and Kristensen introduce the constructs of the CPN modelling language and present the related analysis methods in detail. They also provide a comprehensive road map for the practical use of CPN by showcasing selected industrial case...

  13. Confined space fatalities in Virginia. (United States)

    Sahli, B P; Armstrong, C W


    To better understand the frequency and characteristics of occupational confined space fatalities in Virginia, we reviewed death certificates, workers' compensation files, a Virginia Occupational Safety and Health Administration listing, and medical examiner records for all 50 fatalities (41 accidents) reported during 1979 to 1986. All fatalities were identified in medical examiner records (50), more than in any other source. The majority of decedents were male craftsmen, operators, or laborers less than 50 years old (mean 38). Drug screens of the 43 decedents tested were negative, with the exception of 2 cases where blood alcohol was detected (greater than or equal to 0.06%). Approximately 5% of "at work" civilian deaths (excluding plane, train, and motor vehicle fatalities) were confined space related. Virginia resident death rates per million employees were highest for shipbuilding and repair facilities (23.2), local government (8.9), and manufacturing other than shipbuilding (5.4%). Multiple fatalities occurred in 4 (10%) of the accidents, with 3 involving 2 fatalities each, and 1 accident involving 7 fatalities. Three fatalities (6%) were rescuers. Fifty nonfatal injuries of rescuers were known to have occurred in these accidents, 15 of co-workers and 35 of community rescue personnel (firefighters and rescue squad members). Approximately half the accidents occurred during the fourth quarter of the year and on a Thursday or Friday, and about one third occurred at night. The leading accident type was atmospheric condition, most commonly oxygen deficiency (33%) or the presence of carbon monoxide (20%). In 6 (40%) of the 15 accidents involving atmospheric condition, the toxic gas or oxygen deficiency was absent in the confined space at the time of entry.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Weak polyelectrolytes in Confined Geometries (United States)

    Whitmer, Jonathan K.; Rathee, Vikramjit S.; Sikora, Benjamin

    Crucial to the behavior of recently designed charge-rejection and mosaic membranes are the conformations of polyelectrolyte brushes and oligomeric grafts used to control the membranes' surface charge. The use of pH-tunable weak polyelectrolytes with associative interactions enables fine tuning of material transport properties. Here, we apply constant-pH molecular dynamics along with free energy sampling algorithms to understand the subtle tug-of-war between pH, salt concentrations, and solvation forces in confined systems, and determine how each of these effects alters transport within the system. We further discuss the implications of our findings for the design of electrolyte separation membranes.

  15. Liquid Spreading under Nanoscale Confinement (United States)

    Checco, Antonio


    Dynamic atomic force microscopy in the noncontact regime is used to study the morphology of a nonvolatile liquid (squalane) as it spreads along wettable nanostripes embedded in a nonwettable surface. Results show that the liquid profile depends on the amount of lateral confinement imposed by the nanostripes, and it is truncated at the microscopic contact line in good qualitative agreement with classical mesoscale hydrodynamics. However, the width of the contact line is found to be significantly larger than expected theoretically. This behavior may originate from small chemical inhomogeneity of the patterned stripes as well as from thermal fluctuations of the contact line.

  16. Spatial variation in tuber depletion by swans explained by differences in net intake rates

    NARCIS (Netherlands)

    Nolet, BA; Langevoord, O; Bevan, RM; Engelaar, KR; Klaassen, M; Mulder, RJW

    We tested whether the spatial variation in resource depletion by Tundra Swans (Cygnus columbianus) foraging on belowground tubers of sage pondweed (Potnmogeton pectinatus) was caused by differences in net energy intake rates. The variation in giving up densities within the confines of one lake was

  17. Spatial variation in tuber depletion by swans explained by differences in net intake rates

    NARCIS (Netherlands)

    Nolet, B.A.; Langevoord, O.; Bevan, R.M.; Engelaar, K.R.; Klaassen, M.R.J.; Mulder, R.J.W.; Van Dijk, S.


    We tested whether the spatial variation in resource depletion by Tundra Swans (Cygnus columbianus) foraging on belowground tubers of sage pondweed (Potnmogeton pectinatus) was caused by differences in net energy intake rates. The variation in giving up densities within the confines of one lake was

  18. Quantum confinement in Si and Ge nanostructures: Theory and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Barbagiovanni, Eric G., E-mail: [Laboratory for Simulation of Physical Systems, Beijing Computational Science Research Centre, Beijing 100084 (China); Lockwood, David J. [National Research Council, Ottawa, Ontario K1A 0R6 (Canada); Simpson, Peter J.; Goncharova, Lyudmila V. [Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada)


    The role of quantum confinement (QC) in Si and Ge nanostructures (NSs) including quantum dots, quantum wires, and quantum wells is assessed under a wide variety of fabrication methods in terms of both their structural and optical properties. Structural properties include interface states, defect states in a matrix material, and stress, all of which alter the electronic states and hence the measured optical properties. We demonstrate how variations in the fabrication method lead to differences in the NS properties, where the most relevant parameters for each type of fabrication method are highlighted. Si embedded in, or layered between, SiO{sub 2}, and the role of the sub-oxide interface states embodies much of the discussion. Other matrix materials include Si{sub 3}N{sub 4} and Al{sub 2}O{sub 3}. Si NSs exhibit a complicated optical spectrum, because the coupling between the interface states and the confined carriers manifests with varying magnitude depending on the dimension of confinement. Ge NSs do not produce well-defined luminescence due to confined carriers, because of the strong influence from oxygen vacancy defect states. Variations in Si and Ge NS properties are considered in terms of different theoretical models of QC (effective mass approximation, tight binding method, and pseudopotential method). For each theoretical model, we discuss the treatment of the relevant experimental parameters.

  19. Magnetic confinement fusion energy research

    Energy Technology Data Exchange (ETDEWEB)

    Grad, H


    Controlled Thermonuclear Fusion offers probably the only relatively clean energy solution with completely inexhaustible fuel and unlimited power capacity. The scientific and technological problem consists in magnetically confining a hot, dense plasma (pressure several to hundreds of atmospheres, temperature 10/sup 8/ degrees or more) for an appreciable fraction of a second. The scientific and mathematical problem is to describe the behavior, such as confinement, stability, flow, compression, heating, energy transfer and diffusion of this medium in the presence of electromagnetic fields just as we now can for air or steam. Some of the extant theory consists of applications, routine or ingenious, of known mathematical structures in the theory of differential equations and in traditional analysis. Other applications of known mathematical structures offer surprises and new insights: the coordination between sub-supersonic and elliptic-hyperbolic is fractured; supersonic propagation goes upstream; etc. Other completely nonstandard mathematical structures with significant theory are being rapidly uncovered (and somewhat less rapidly understood) such as non-elliptic variational equations and new types of weak solutions. It is these new mathematical structures which one should expect to supply the foundation for the next generation's pure mathematics, if history is a guide. Despite the substantial effort over a period of some twenty years, there are still basic and important scintific and mathematical discoveries to be made, lying just beneath the surface.

  20. Three-Dimensional Finite Element Analysis of Compressive Behavior of Circular Steel Tube-Confined Concrete Stub Columns by New Confinement Relationships

    Directory of Open Access Journals (Sweden)

    Akbar Haghinejada

    Full Text Available Abstract This paper presents a nonlinear analysis of axially loaded steel tube-confined concrete (STCC stub columns with new confinement relationships. For this aim, a 3-D finite element model of STCC columns using ABAQUS program is developed and validated against the experimental data. Proper material constitutive models are proposed and the confinement parameters of confined concrete are determined by matching the numerical results via trial and error. The parameters considered for quantitative verification of the FE model include five different factors indicating the behavior of STCC columns: compressive strength corresponding to steel yielding point, initial peak strength and ultimate strength as well as longitudinal to circumferential stress ratio of steel tube at steel yielding point and initial peak point. For the qualitative verification, the axial and lateral stress-strain relationships of STCC columns are taken into account. The comparison results indicate that the model can accurately predict the compressive behavior of STCC stub columns. Finally, a parametric study is also performed to evaluate the effect of tube diameter-to-wall thickness ratio (D/t, concrete compressive strength (fc and steel yield strength (fy on the compressive behavior of STCC columns. According to the results of the parametric study, the interface shear stress and lateral confining pressure are not affected by fc while significantly increase with decreasing D/t.

  1. Effects of Moving Side Walls on Confined Granular Packings

    Directory of Open Access Journals (Sweden)

    Ram Chand


    Full Text Available Granular materials have numerous industrial and geophysical applications. However, many phenomenon exhibited by granular media are not yet fully explained. Nowadays simulation has emerged as an important tool to investigate the complex properties exhibited by granular media. The influence of side walls movement of a granular column is investigated by discrete element, molecular dynamics simulations. The evolution of stress profile and deflection of vertical stresses is due to different bead sizes, coefficient of friction between grains and confining wall is investigated by using large-scale discrete element MD simulations in 3D. In such a configuration, it is found that apparent mass systemically increases with the increase in diameter of granules. As soon as the wall stops moving, the column attains equilibrium. The stress profiles are in good agreement with the Janssen form for high friction coefficient, while some deviations remain for smaller values of friction coefficient. The wall movement augments the number of particle-wall and particle-particle forces at the Coulomb criterion. The results indicate the variation in shielding of vertical stresses in granular column; it can be attributed to the fiction between the beads and the confining walls of the container.

  2. Spatially confined assembly of nanoparticles. (United States)

    Jiang, Lin; Chen, Xiaodong; Lu, Nan; Chi, Lifeng


    an increasingly important role in the controllable assembly of NPs. In this Account, we summarize our approaches and progress in fabricating spatially confined assemblies of NPs that allow for the positioning of NPs with high resolution and considerable throughput. The spatially selective assembly of NPs at the desired location can be achieved by various mechanisms, such as, a controlled dewetting process, electrostatically mediated assembly of particles, and confined deposition and growth of NPs. Three nanofabrication techniques used to produce prepatterns on a substrate are summarized: the Langmuir-Blodgett (LB) patterning technique, e-beam lithography (EBL), and nanoimprint lithography (NPL). The particle density, particle size, or interparticle distance in NP assemblies strongly depends on the geometric parameters of the template structure due to spatial confinement. In addition, with smart design template structures, multiplexed NPs can be assembled into a defined structure, thus demonstrating the structural and functional complexity required for highly integrated and multifunction applications.

  3. Linear Logic on Petri Nets

    DEFF Research Database (Denmark)

    Engberg, Uffe Henrik; Winskel, Glynn

    This article shows how individual Petri nets form models of Girard's intuitionistic linear logic. It explores questions of expressiveness and completeness of linear logic with respect to this interpretation. An aim is to use Petri nets to give an understanding of linear logic and give some apprai...

  4. Reference Guide Microsoft.NET

    NARCIS (Netherlands)

    Zee M van der; Verspaij GJ; Rosbergen S; IMP; NMD


    Developers, administrators and managers can get more understanding of the .NET technology with this report. They can also make better choices how to use this technology. The report describes the results and conclusions of a study of the usability for the RIVM of this new generation .NET development

  5. Net neutrality and audiovisual services

    NARCIS (Netherlands)

    van Eijk, N.; Nikoltchev, S.


    Net neutrality is high on the European agenda. New regulations for the communication sector provide a legal framework for net neutrality and need to be implemented on both a European and a national level. The key element is not just about blocking or slowing down traffic across communication

  6. A Small Universal Petri Net

    Directory of Open Access Journals (Sweden)

    Dmitry A. Zaitsev


    Full Text Available A universal deterministic inhibitor Petri net with 14 places, 29 transitions and 138 arcs was constructed via simulation of Neary and Woods' weakly universal Turing machine with 2 states and 4 symbols; the total time complexity is exponential in the running time of their weak machine. To simulate the blank words of the weakly universal Turing machine, a couple of dedicated transitions insert their codes when reaching edges of the working zone. To complete a chain of a given Petri net encoding to be executed by the universal Petri net, a translation of a bi-tag system into a Turing machine was constructed. The constructed Petri net is universal in the standard sense; a weaker form of universality for Petri nets was not introduced in this work.

  7. Quark Confinement and Force Unification

    Directory of Open Access Journals (Sweden)

    Stone R. A. Jr.


    Full Text Available String theory had to adopt a bi-scale approach in order to produce the weakness of gravity. Taking a bi-scale approach to particle physics along with a spin connection produces 1 the measured proton radius, 2 a resolution of the multiplicity of measured weak angle values 3 a correct theoretical value for the Z 0 4 a reason that h is a constant and 5 a “neutral current” source. The source of the “neutral current” provides 6 an alternate solution to quark confinement, 7 produces an effective r like potential, and 8 gives a reason for the observed but unexplained Regge trajectory like J M 2 behavior seen in quark composite particle spin families.

  8. Dependency of hydromechanical properties of monzonitic granite on confining pressure and fluid pressure under compression (United States)

    Wang, Huanling; Xu, Weiya; Lui, Zaobao; Chao, Zhiming; Meng, Qingxiang


    Monzonitic granite is a low-permeability rock. Monzonitic granite formations are ideal for underground storage of oil due to their low permeability and high mechanical strength. In this study, a series of coupled hydromechanical triaxial tests are carried out using monzonitic granite specimens. The influence of confining and fluid pressures on stress, strain, and permeability is investigated. Failure characteristics under different confining and fluid pressures are discussed based on the analysis of macro fracture planes and micro scanning electron microscopy (SEM). The test results show that the change of permeability with stress and strain reflects the deformation stages of compaction, compression, crack propagation, coalesce, and failure of cracks. Due to the low porosity, the change of permeability is small in the initial phases of compaction and compression, whereas there is a significant increase in permeability when new cracks start to develop and coalesce. Confining pressures have a significant impact on the strength and permeability, particularly the crack damage stress of the rock. Compared with confining pressure, the effect of fluid pressure on rock strength and crack damage stress is small. For the monzonitic granite specimens tested, changing the confining pressure results in different failure modes, whereas the fluid pressure has a relatively small effect on the failure modes.

  9. High-level Petri Nets

    DEFF Research Database (Denmark)

    High-level Petri nets are now widely used in both theoretical analysis and practical modelling of concurrent systems. The main reason for the success of this class of net models is that they make it possible to obtain much more succinct and manageable descriptions than can be obtained by means...... of low-level Petri nets - while, on the other hand, they still offer a wide range of analysis methods and tools. The step from low-level nets to high-level nets can be compared to the step from assembly languages to modern programming languages with an elaborated type concept. In low-level nets...... there is only one kind of token and this means that the state of a place is described by an integer (and in many cases even by a boolean). In high-level nets each token can carry a complex information/data - which, e.g., may describe the entire state of a process or a data base. Today most practical...

  10. Individualized Stress Detection System Project (United States)

    National Aeronautics and Space Administration — Given the extended duration of future missions and the isolated, extreme, and confined environments, there is the possibility that stress-related behavioral...

  11. Individualized Stress Detection System Project (United States)

    National Aeronautics and Space Administration — Given the extended duration of future missions and the isolated, extreme and confined environments, there is the possibility that stress-related behavioral...

  12. Water use efficiency of net primary production in global terrestrial ...

    Indian Academy of Sciences (India)

    Water use efficiency; global terrestrial ecosystems; MODIS; net primary production; evapotranspiration;. Köppen–Geiger climate classification. ... Terrestrial plants fix or trap carbon dioxide via photosynthesis to produce the material ...... S W 2007 Evaluating water stress controls on primary production in biogeochemical and ...

  13. Pro asynchronous programming with .NET

    CERN Document Server

    Blewett, Richard; Ltd, Rock Solid Knowledge


    Pro Asynchronous Programming with .NET teaches the essential skill of asynchronous programming in .NET. It answers critical questions in .NET application development, such as: how do I keep my program responding at all times to keep my users happy how do I make the most of the available hardware how can I improve performanceIn the modern world, users expect more and more from their applications and devices, and multi-core hardware has the potential to provide it. But it takes carefully crafted code to turn that potential into responsive, scalable applications.With Pro Asynchronous Programming

  14. Conformal Nets II: Conformal Blocks (United States)

    Bartels, Arthur; Douglas, Christopher L.; Henriques, André


    Conformal nets provide a mathematical formalism for conformal field theory. Associated to a conformal net with finite index, we give a construction of the `bundle of conformal blocks', a representation of the mapping class groupoid of closed topological surfaces into the category of finite-dimensional projective Hilbert spaces. We also construct infinite-dimensional spaces of conformal blocks for topological surfaces with smooth boundary. We prove that the conformal blocks satisfy a factorization formula for gluing surfaces along circles, and an analogous formula for gluing surfaces along intervals. We use this interval factorization property to give a new proof of the modularity of the category of representations of a conformal net.

  15. Degraded confinement and turbulence in tokamak experiments

    NARCIS (Netherlands)

    Schüller, F. C.


    After a review on the state of tokamak transport theory, the methodology to derive experimental results will be described. Examples of confinement in ohmic plasmas and the deterioration with additional heating will be given. Some examples of improved confinement modes will be discussed. Fluctuation

  16. Degraded confinement and turbulence in tokamak experiments

    NARCIS (Netherlands)

    Hogeweij, G. M. D.


    After a review on the state of tokamak transport theory, the methodology to derive experimental results will be described. Examples of confinement in ohmic plasmas and the deterioration with additional healing will be given. Some examples of improved confinement; modes will be discussed.

  17. Confinement of charge carriers in bilayer graphene

    NARCIS (Netherlands)

    Goossens, A.M.


    In this thesis we investigate the fundamental properties of electronic transport in bilayer graphene. We do this by confining electrons to narrow constrictions and small islands. Our key result is the fabrication and measurement of nanoscale devices that permit confinement with electric fields in

  18. Structure of polymer chains under confinement

    Indian Academy of Sciences (India)

    Single chain form factor was observed both for bulk and confined chains using the condition of zero average contrast. Our measurements on neutral polymer chains are in agreement with the theoretical predictions established by Daoud and de Gennes for chains confined in a cylindrical pore when the chains are entangled ...

  19. Polymer Dynamics under Cylindrical Nano-Confinement (United States)

    Winey, Karen; Tung, Wei-Shao; Riggleman, Robert


    Polymer melts under cylindrical confinement have previously been shown to exhibit chain conformations elongated parallel to the cylinder axis and compressed perpendicular to the cylinder. Further, simulations and theory found that the number of entanglements per chain decreases as the cylinder diameter decreases. This talk presents the local dynamics and polymer diffusion under cylindrical nanoconfinement using simulations and experiments. For the molecular dynamics simulations, an entangled polymer is confined by an amorphous cylindrical confinement. Local dynamics and local packing of monomers are affected by the cylindrical confinement and an anisotropic mean-squared displacement is observed with faster motion along the cylinder axes that increases with increasing confinement. Using elastic recoil detection experiments, polymer diffusion coefficients along cylindrical nanopores were measured for deuterated polystyrene diffusing into nanoporous membranes infiltrated with polystyrene. The tracer diffusion coefficient increased with decreasing pore size, although the increase is less pronounced than found in the simulations. Results will be discussed in terms of the reptation model.

  20. Petri Net Tool Overview 1986

    DEFF Research Database (Denmark)

    Jensen, Kurt; Feldbrugge, Frits


    This paper provides an overview of the characteristics of all currently available net based tools. It is a compilation of information provided by tool authors or contact persons. A concise one page overview is provided as well....

  1. Understanding Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Salom, Jaume; Widén, Joakim; Candanedo, José


    Although several alternative definitions exist, a Net-Zero Energy Building (Net ZEB) can be succinctly described as a grid-connected building that generates as much energy as it uses over a year. The “net-zero” balance is attained by applying energy conservation and efficiency measures...... and by incorporating renewable energy systems. While based on annual balances, a complete description of a Net ZEB requires examining the system at smaller time-scales. This assessment should address: (a) the relationship between power generation and building loads and (b) the resulting interaction with the power grid....... This paper presents and categorizes quantitative indicators suitable to describe both aspects of the building’s performance. These indicators, named LMGI - Load Matching and Grid Interaction indicators, are easily quantifiable and could complement the output variables of existing building simulation tools...

  2. PolicyNet Publication System (United States)

    Social Security Administration — The PolicyNet Publication System project will merge the Oracle-based Policy Repository (POMS) and the SQL-Server CAMP system (MSOM) into a new system with an Oracle...

  3. KM3NeT

    CERN Multimedia

    KM3NeT is a large scale next-generation neutrino telescope located in the deep waters of the Mediterranean Sea, optimized for the discovery of galactic neutrino sources emitting in the TeV energy region.

  4. Net Neutrality: Background and Issues

    National Research Council Canada - National Science Library

    Gilroy, Angele A


    .... The move to place restrictions on the owners of the networks that compose and provide access to the Internet, to ensure equal access and nondiscriminatory treatment, is referred to as "net neutrality...

  5. Fermion Superfluidity And Confining Interactions

    CERN Document Server

    Galal, A A


    We study the pairing of Fermi systems with long-range, confining interparticle interactions. We solve the Cooper problem for a pair of fermions interacting via a regularized harmonic oscillator potential and determine the s-wave spectrum of bound states. Using a model of two interacting species of fermions, we calculate the ground state energy of the normal phase in the Hartree-Fock approximation and find that it is infrared (IR) divergent, due to a combination of the sharpness of the Fermi sea and the long-range nature of the interaction. We calculate the correlation energy in the normal phase using the random phase approximation (RPA) and demonstrate the cancellation of infrared divergences between the Hartree-Fock and RPA contributions. Introducing a variational wavefunction to study the superfluid phase, we solve the BCS equations using a Hartree-Fock-Bogoliubov (HFB) analysis to determine the wave-function, excitation gap, and other parameters of the superfluid phase. We show that the system crosses over...

  6. Petri Nets in Cryptographic Protocols

    DEFF Research Database (Denmark)

    Crazzolara, Federico; Winskel, Glynn


    A process language for security protocols is presented together with a semantics in terms of sets of events. The denotation of process is a set of events, and as each event specifies a set of pre and postconditions, this denotation can be viewed as a Petri net. By means of an example we illustrate...... how the Petri-net semantics can be used to prove security properties....

  7. The Economics of Net Neutrality


    Hahn, Robert W.; Wallsten, Scott


    This essay examines the economics of "net neutrality" and broadband Internet access. We argue that mandating net neutrality would be likely to reduce economic welfare. Instead, the government should focus on creating competition in the broadband market by liberalizing more spectrum and reducing entry barriers created by certain local regulations. In cases where a broadband provider can exercise market power the government should use its antitrust enforcement authority to police anticompetitiv...

  8. An experimental method of measuring the quasi-static and dynamic confined behaviour of PMMA

    Directory of Open Access Journals (Sweden)

    Siad L.


    Full Text Available A testing device is presented for the experimental study of the confined behaviour of PMMA in compression under quasi-static loading or at high strain-rates. The constitutive relation of the material ring (allowing to confine the PMMA being known, transverse gauges glued on its lateral surface allow for the measurement of the lateral confining pressure. The hydrostatic pressure and the Mises stress may be computed. Quasi-static and dynamic tests performed in a strain-rate range of 1e-3/s 1e3/s are processed with the method and compared to results of unconfined compression tests. It is found that the compressive behaviour of PMMA is weakly influenced by the level of pressure and much more sensitive to strain-rate: an elastic brittle behaviour is observed at high strain-rates in unconfined or confined conditions whereas elastoplastic behaviour is noted under quasi-static loading.

  9. 26 CFR 1.904(f)-3 - Allocation of net operating losses and net capital losses. (United States)


    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Allocation of net operating losses and net....904(f)-3 Allocation of net operating losses and net capital losses. For rules relating to the allocation of net operating losses and net capital losses, see § 1.904(g)-3T. ...

  10. 29 CFR 4204.13 - Net income and net tangible assets tests. (United States)


    ... 29 Labor 9 2010-07-01 2010-07-01 false Net income and net tangible assets tests. 4204.13 Section....13 Net income and net tangible assets tests. (a) General. The criteria under this section are that either— (1) Net income test. The purchaser's average net income after taxes for its three most recent...

  11. Kinetics of Phase Separation in Confined Geometries (United States)

    Puri, Sanjay

    We review analytical and numerical results for the kinetics of phase separation in confined geometries. It is often the case that a confining surface has a preferential attraction for one of the components of a segregating mixture. The equilibrium surface morphology is either partially wet or completely wet, depending on the strength of the surface potential. The dynamical interplay of wetting and phase separation is referred to as surface-directed spinodal decomposition (SDSD), and is of considerable technological importance. We discuss the modeling of SDSD at both the microscopic and coarse-grained levels. We also present results for SDSD in both semi-infinite and confined geometries.

  12. Correlation of TEM data with confined phonons to determine strain and size of Ge nanocrystals embedded in SixNy matrix (United States)

    Bahariqushchi, Rahim; Gündoğdu, Sinan; Aydinli, Atilla


    Models that use phonon confinement fail to provide consistent results for nanocrystal sizes in differing dielectric matrices due to varying stress experienced by nanocrystals in different dielectric environments. In cases where direct measurement of stress is difficult, the possibility of stress saturation as a function of size opens up a window for the use of phonon confinement to determine size. We report on a test of this possibility in Ge: SixNy system. Ge nanocrystals (NCs) embedded in silicon nitride matrix have been fabricated using plasma enhanced chemical vapor deposition (PECVD) followed by post annealing in Ar ambient. Nanocrystal size dependence of Raman spectra was studied taking into account associated stress and an improved phonon confinement approach. Our analysis show same stress for NCs which have sizes below 7.0 nm allowing the use of phonon confinement to determine the nanocrystal size. The results are compared with TEM data and good agreement is observed.

  13. Net transport of suspended matter due to tidal straining (United States)

    Jones, S. E.; Jago, C. F.; Simpson, J. H.; Rippeth, T. P.


    Net transport of suspended particulate matter (SPM) is well-known in tidal regions where there is time-velocity asymmetry due to frictional modification of the tide in shallow water. We present here observations which show a new mechanism for net flux of SPM in response to tidal straining in a region of freshwater influence (ROFI). In situ measurements of the particle size of suspended particulate matter (SPM) and turbulent energy dissipation have been made at a site in Liverpool Bay (Irish Sea) where there is significant resuspension of particles from the muddy sand substrate during spring tides. This is a ROFI where tidal straining dominates the temporal development of turbulence. On a spring tide the water column tries to stratify on the ebb and destratify on the flood, but these tendencies are masked by mixing due to tidal stirring. Nevertheless, there is a marked excess of TKE dissipation rate E on the flood, especially in the upper part of the water column. Resuspension occurs on both flood and ebb, but SPM flux is strongly asymmetric with a net shorewards component. Asymmetry is most pronounced for the larger particles which comprise most of the mass. Enhanced ? on the flood mixes large particles upwards into faster flowing water, which increases the flux. Comparable upwards mixing of large particles does not occur on the ebb where enhanced E is confined to slower bottom waters. The net flux is not seen on neap tides because, although there is more stratification due to tidal straining, there is essentially no resuspension. The net flux on springs is undoubtedly an important component of SPM transport (and any comparable particulates) in coastal regions.

  14. Electronic Quantum Confinement in Cylindrical Potential Well

    CERN Document Server

    Baltenkov, A S


    The effects of quantum confinement on the momentum distribution of electrons confined within a cylindrical potential well have been analyzed. The motivation is to understand specific features of the momentum distribution of electrons when the electron behavior is completely controlled by the parameters of a non-isotropic potential cavity. It is shown that studying the solutions of the wave equation for an electron confined in a cylindrical potential well offers the possibility to analyze the confinement behavior of an electron executing one- or two-dimensional motion in the three-dimensional space within the framework of the same mathematical model. Some low-lying electronic states with different symmetries have been considered and the corresponding wave functions have been calculated; the behavior of their nodes and their peak positions with respect to the parameters of the cylindrical well has been analyzed. Additionally, the momentum distributions of electrons in these states have been calculated. The limi...

  15. Plasma confinement system and methods for use

    Energy Technology Data Exchange (ETDEWEB)

    Jarboe, Thomas R.; Sutherland, Derek


    A plasma confinement system is provided that includes a confinement chamber that includes one or more enclosures of respective helicity injectors. The one or more enclosures are coupled to ports at an outer radius of the confinement chamber. The system further includes one or more conductive coils aligned substantially parallel to the one or more enclosures and a further set of one or more conductive coils respectively surrounding portions of the one or more enclosures. Currents may be provided to the sets of conductive coils to energize a gas within the confinement chamber into a plasma. Further, a heat-exchange system is provided that includes an inner wall, an intermediate wall, an outer wall, and pipe sections configured to carry coolant through cavities formed by the walls.

  16. Anisotropic hydrodynamic function of dense confined colloids (United States)

    Nygârd, Kim; Buitenhuis, Johan; Kagias, Matias; Jefimovs, Konstantins; Zontone, Federico; Chushkin, Yuriy


    Dense colloidal dispersions exhibit complex wave-vector-dependent diffusion, which is controlled by both direct particle interactions and indirect nonadditive hydrodynamic interactions mediated by the solvent. In bulk the hydrodynamic interactions are probed routinely, but in confined geometries their studies have been hitherto hindered by additional complications due to confining walls. Here we solve this issue by combining high-energy x-ray photon correlation spectroscopy and small-angle x-ray-scattering experiments on colloid-filled microfluidic channels to yield the confined fluid's hydrodynamic function in the short-time limit. Most importantly, we find the confined fluid to exhibit a strongly anisotropic hydrodynamic function, similar to its anisotropic structure factor. This observation is important in order to guide future theoretical research.

  17. Reorientational dynamics of water confined in zeolites. (United States)

    Fogarty, Aoife C; Coudert, François-Xavier; Boutin, Anne; Laage, Damien


    We present a detailed molecular-dynamics study of water reorientation and hydrogen-bond dynamics in a strong confinement situation, within the narrow pores of an all-silica Linde type A (LTA) zeolite. Two water loadings of the zeolite are compared with the bulk case. Water dynamics are retarded in this extreme hydrophobic confinement and the slowdown is more pronounced at higher water loading. We show that water reorientation proceeds mainly by large-amplitude angular jumps, whose mechanism is similar to that determined in the bulk. The slowdown upon hydrophobic confinement arises predominantly from an excluded-volume effect on the large fraction of water molecules lying at the interface with the zeolite matrix, with an additional minor contribution coming from a structuring effect induced by the confinement. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Group Velocity Engineering of Confined Ultrafast Magnons (United States)

    Chen, Y.-J.; Zakeri, Kh.; Ernst, A.; Qin, H. J.; Meng, Y.; Kirschner, J.


    Quantum confinement permits the existence of multiple terahertz magnon modes in atomically engineered ultrathin magnetic films and multilayers. By means of spin-polarized high-resolution electron energy-loss spectroscopy, we report on the direct experimental detection of all exchange-dominated terahertz confined magnon modes in a 3 ML Co film. We demonstrate that, by tuning the structural and magnetic properties of the Co film, through its epitaxial growth on different surfaces, e.g., Ir(001), Cu(001), and Pt(111), one can achieve entirely different in-plane magnon dispersions, characterized by positive and negative group velocities. Our first-principles calculations show that spin-dependent many-body correlation effects in Co films play an important role in the determination of the energies of confined magnon modes. Our results suggest a pathway towards the engineering of the group velocity of confined ultrafast magnons.

  19. Monte Carlo simulations of confined polymer systems

    NARCIS (Netherlands)

    Vliet, Johannes Henricus van


    This thesis considers confined polymer systems. These systems are of considerable interest, e.g., thin polymer films, chromotography of polymer solutions, drag reduction, enhanced oil recovery, stabilization of colloidal dispersions, lubrication and biolubrication. The method used to study these

  20. TimeNET Optimization Environment

    Directory of Open Access Journals (Sweden)

    Christoph Bodenstein


    Full Text Available In this paper a novel tool for simulation-based optimization and design-space exploration of Stochastic Colored Petri nets (SCPN is introduced. The working title of this tool is TimeNET Optimization Environment (TOE. Targeted users of this tool are people modeling complex systems with SCPNs in TimeNET who want to find parameter sets that are optimal for a certain performance measure (fitness function. It allows users to create and simulate sets of SCPNs and to run different optimization algorithms based on parameter variation. The development of this tool was motivated by the need to automate and speed up tests of heuristic optimization algorithms to be applied for SCPN optimization. A result caching mechanism is used to avoid recalculations.

  1. Aspects of Confinement in Low Dimensions (United States)

    Bhaseen, M. J.; Tsvelik, A. M.

    We briefly review some examples of confinement which arise in condensed matter physics. We focus on two instructive cases: the off-critical Ising model in a magnetic field, and an array of weakly coupled (extended) Hubbard chains in the Wigner crystal phase. In the appropriate regime, the elementary excitations in these 1 + 1 and quasi-one-dimensional systems are confined into `mesons'. Although the models are generically non-integrable, quantum mechanics and form-factor techniques yield valuable information.

  2. Implementing NetScaler VPX

    CERN Document Server

    Sandbu, Marius


    An easy-to-follow guide with detailed step-by step-instructions on how to implement the different key components in NetScaler, with real-world examples and sample scenarios.If you are a Citrix or network administrator who needs to implement NetScaler in your virtual environment to gain an insight on its functionality, this book is ideal for you. A basic understanding of networking and familiarity with some of the different Citrix products such as XenApp or XenDesktop is a prerequisite.

  3. Net4Care PHMR Library

    DEFF Research Database (Denmark)


    The Net4Care PHMR library contains a) A GreenCDA approach for constructing a data object representing a PHMR document: SimpleClinicalDocument, and b) A Builder which can produce a XML document representing a valid Danish PHMR (following the MedCom profile) document from the SimpleClinicalDocument......The Net4Care PHMR library contains a) A GreenCDA approach for constructing a data object representing a PHMR document: SimpleClinicalDocument, and b) A Builder which can produce a XML document representing a valid Danish PHMR (following the MedCom profile) document from the Simple...

  4. Pro DLR in NET 4

    CERN Document Server

    Wu, Chaur


    Microsoft's Dynamic Language Runtime (DLR) is a platform for running dynamic languages such as Ruby and Python on an equal footing with compiled languages such as C#. Furthermore, the runtime is the foundation for many useful software design and architecture techniques you can apply as you develop your .NET applications. Pro DLR in .NET 4 introduces you to the DLR, showing how you can use it to write software that combines dynamic and static languages, letting you choose the right tool for the job. You will learn the core DLR components such as LINQ expressions, call sites, binders, and dynami

  5. Hierarchies in Coloured Petri Nets

    DEFF Research Database (Denmark)

    Huber, Peter; Jensen, Kurt; Shapiro, Robert M.


    The paper shows how to extend Coloured Petri Nets with a hierarchy concept. The paper proposes five different hierarchy constructs, which allow the analyst to structure large CP-nets as a set of interrelated subnets (called pages). The paper discusses the properties of the proposed hierarchy...... constructs, and it illustrates them by means of two examples. The hierarchy constructs can be used for theoretical considerations, but their main use is to describe and analyse large real-world systems. All of the hierarchy constructs are supported by the editing and analysis facilities in the CPN Palette...

  6. Confined Space Evaluation Student Manual, #19613

    Energy Technology Data Exchange (ETDEWEB)

    Wilmot, David Ezekiel [Los Alamos National Laboratory


    Many workplaces contain spaces that are considered to be “confined” because their configuration hinders the activities of employees who must enter into, work in, and exit from them. In general, the permit-required confined spaces (PRCSs) Occupational Safety and Health Administration (OSHA) standard requires that Los Alamos National Laboratory (LANL) evaluate the workplace to determine if any spaces are PRCSs. The standard specifies strict procedures for the evaluation and atmospheric testing of a space before and during an entry by workers. The OSHA PRCS standard provides for alternative (less stringent than full-permit) entry procedures in cases where the only hazard in a space is atmospheric and the hazard can be controlled by forced air. At LANL, all confined spaces or potential confined spaces on LANL-owned or -operated property must be identified and evaluated by a confined space evaluator accompanied by a knowledgeable person. This course provides the information needed by confined space evaluators to make judgements about whether a space is a confined space, and if so, whether the space will require a permit for entry.

  7. Methods for two-dimensional cell confinement. (United States)

    Le Berre, Maël; Zlotek-Zlotkiewicz, Ewa; Bonazzi, Daria; Lautenschlaeger, Franziska; Piel, Matthieu


    Protocols described in this chapter relate to a method to dynamically confine cells in two dimensions with various microenvironments. It can be used to impose on cells a given height, with an accuracy of less than 100 nm on large surfaces (cm(2)). The method is based on the gentle application of a modified glass coverslip onto a standard cell culture. Depending on the preparation, this confinement slide can impose on the cells a given geometry but also an environment of controlled stiffness, controlled adhesion, or a more complex environment. An advantage is that the method is compatible with most optical microscopy technologies and molecular biology protocols allowing advanced analysis of confined cells. In this chapter, we first explain the principle and issues of using these slides to confine cells in a controlled geometry and describe their fabrication. Finally, we discuss how the nature of the confinement slide can vary and provide an alternative method to confine cells with gels of controlled rigidity. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. An Experimental Study of Dynamic Tensile Failure of Rocks Subjected to Hydrostatic Confinement (United States)

    Wu, Bangbiao; Yao, Wei; Xia, Kaiwen


    It is critical to understand the dynamic tensile failure of confined rocks in many rock engineering applications, such as underground blasting in mining projects. To simulate the in situ stress state of underground rocks, a modified split Hopkinson pressure bar system is utilized to load Brazilian disc (BD) samples hydrostatically, and then exert dynamic load to the sample by impacting the striker on the incident bar. The pulse shaper technique is used to generate a slowly rising stress wave to facilitate the dynamic force balance in the tests. Five groups of Laurentian granite BD samples (with static BD tensile strength of 12.8 MPa) under the hydrostatic confinement of 0, 5, 10, 15, and 20 MPa were tested with different loading rates. The result shows that the dynamic tensile strength increases with the hydrostatic confining pressure. It is also observed that under the same hydrostatic pressure, the dynamic tensile strength increases with the loading rate, revealing the so-called rate dependency for engineering materials. Furthermore, the increment of the tensile strength decreases with the hydrostatic confinement, which resembles the static tensile behavior of rock under confining pressure, as reported in the literature. The recovered samples are examined using X-ray micro-computed tomography method and the observed crack pattern is consistent with the experimental result.

  9. Topology of polymer chains under nanoscale confinement. (United States)

    Satarifard, Vahid; Heidari, Maziar; Mashaghi, Samaneh; Tans, Sander J; Ejtehadi, Mohammad Reza; Mashaghi, Alireza


    Spatial confinement limits the conformational space accessible to biomolecules but the implications for bimolecular topology are not yet known. Folded linear biopolymers can be seen as molecular circuits formed by intramolecular contacts. The pairwise arrangement of intra-chain contacts can be categorized as parallel, series or cross, and has been identified as a topological property. Using molecular dynamics simulations, we determine the contact order distributions and topological circuits of short semi-flexible linear and ring polymer chains with a persistence length of lp under a spherical confinement of radius Rc. At low values of lp/Rc, the entropy of the linear chain leads to the formation of independent contacts along the chain and accordingly, increases the fraction of series topology with respect to other topologies. However, at high lp/Rc, the fraction of cross and parallel topologies are enhanced in the chain topological circuits with cross becoming predominant. At an intermediate confining regime, we identify a critical value of lp/Rc, at which all topological states have equal probability. Confinement thus equalizes the probability of more complex cross and parallel topologies to the level of the more simple, non-cooperative series topology. Moreover, our topology analysis reveals distinct behaviours for ring- and linear polymers under weak confinement; however, we find no difference between ring- and linear polymers under strong confinement. Under weak confinement, ring polymers adopt parallel and series topologies with equal likelihood, while linear polymers show a higher tendency for series arrangement. The radial distribution analysis of the topology reveals a non-uniform effect of confinement on the topology of polymer chains, thereby imposing more pronounced effects on the core region than on the confinement surface. Additionally, our results reveal that over a wide range of confining radii, loops arranged in parallel and cross topologies have

  10. D.NET case study

    International Development Research Centre (IDRC) Digital Library (Canada)


    developing products, marketing tools and building capacity of the grass root telecentre workers. D.Net recognized that it had several ideas worth developing into small interventions that would make big differences, but resource constraints were a barrier for scaling-up these initiatives. More demands, limited resources.

  11. Surgery for GEP-NETs

    DEFF Research Database (Denmark)

    Knigge, Ulrich; Hansen, Carsten Palnæs


    Surgery is the only treatment that may cure the patient with gastroentero-pancreatic (GEP) neuroendocrine tumours (NET) and neuroendocrine carcinomas (NEC) and should always be considered as first line treatment if R0/R1 resection can be achieved. The surgical and interventional procedures for GEP...

  12. Net Neutrality in the Netherlands

    NARCIS (Netherlands)

    van Eijk, N.


    The Netherlands is among the first countries that have put specific net neutrality standards in place. The decision to implement specific regulation was influenced by at least three factors. The first was the prevailing social and academic debate, partly due to developments in the United States. The

  13. Complexity Metrics for Workflow Nets

    DEFF Research Database (Denmark)

    Lassen, Kristian Bisgaard; van der Aalst, Wil M.P.


    Process modeling languages such as EPCs, BPMN, flow charts, UML activity diagrams, Petri nets, etc.\\ are used to model business processes and to configure process-aware information systems. It is known that users have problems understanding these diagrams. In fact, even process engineers and system...

  14. Increased asymmetric and multi-daughter cell division in mechanically confined microenvironments.

    Directory of Open Access Journals (Sweden)

    Henry Tat Kwong Tse

    Full Text Available As the microenvironment of a cell changes, associated mechanical cues may lead to changes in biochemical signaling and inherently mechanical processes such as mitosis. Here we explore the effects of confined mechanical environments on cellular responses during mitosis. Previously, effects of mechanical confinement have been difficult to optically observe in three-dimensional and in vivo systems. To address this challenge, we present a novel microfluidic perfusion culture system that allows controllable variation in the level of confinement in a single axis allowing observation of cell growth and division at the single-cell level. The device is capable of creating precise confinement conditions in the vertical direction varying from high (3 µm to low (7 µm confinement while also varying the substrate stiffness (E = 130 kPa and 1 MPa. The Human cervical carcinoma (HeLa model with a known 3N+ karyotype was used for this study. For this cell line, we observe that mechanically confined cell cycles resulted in stressed cell divisions: (i delayed mitosis, (ii multi- daughter mitosis events (from 3 up to 5 daughter cells, (iii unevenly sized daughter cells, and (iv induction of cell death. In the highest confined conditions, the frequency of divisions producing more than two progeny was increased an astounding 50-fold from unconfined environments, representing about one half of all successful mitotic events. Notably, the majority of daughter cells resulting from multipolar divisions were viable after cytokinesis and, perhaps suggesting another regulatory checkpoint in the cell cycle, were in some cases observed to re-fuse with neighboring cells post-cytokinesis. The higher instances of abnormal mitosis that we report in confined mechanically stiff spaces, may lead to increased rates of abnormal, viable, cells in the population. This work provides support to a hypothesis that environmental mechanical cues influences structural mechanisms of mitosis

  15. Increased asymmetric and multi-daughter cell division in mechanically confined microenvironments. (United States)

    Tse, Henry Tat Kwong; Weaver, Westbrook McConnell; Di Carlo, Dino


    As the microenvironment of a cell changes, associated mechanical cues may lead to changes in biochemical signaling and inherently mechanical processes such as mitosis. Here we explore the effects of confined mechanical environments on cellular responses during mitosis. Previously, effects of mechanical confinement have been difficult to optically observe in three-dimensional and in vivo systems. To address this challenge, we present a novel microfluidic perfusion culture system that allows controllable variation in the level of confinement in a single axis allowing observation of cell growth and division at the single-cell level. The device is capable of creating precise confinement conditions in the vertical direction varying from high (3 µm) to low (7 µm) confinement while also varying the substrate stiffness (E = 130 kPa and 1 MPa). The Human cervical carcinoma (HeLa) model with a known 3N+ karyotype was used for this study. For this cell line, we observe that mechanically confined cell cycles resulted in stressed cell divisions: (i) delayed mitosis, (ii) multi- daughter mitosis events (from 3 up to 5 daughter cells), (iii) unevenly sized daughter cells, and (iv) induction of cell death. In the highest confined conditions, the frequency of divisions producing more than two progeny was increased an astounding 50-fold from unconfined environments, representing about one half of all successful mitotic events. Notably, the majority of daughter cells resulting from multipolar divisions were viable after cytokinesis and, perhaps suggesting another regulatory checkpoint in the cell cycle, were in some cases observed to re-fuse with neighboring cells post-cytokinesis. The higher instances of abnormal mitosis that we report in confined mechanically stiff spaces, may lead to increased rates of abnormal, viable, cells in the population. This work provides support to a hypothesis that environmental mechanical cues influences structural mechanisms of mitosis such as

  16. Confined concrete models according to EC 2 and EC 8 and their influence on the RC frame seismic response

    Directory of Open Access Journals (Sweden)

    Radujković Aleksandra


    Full Text Available Seismic design according to European norms implies the design of ductile rc structures. By confining the concrete, the ratio of stress-strain is changing and increases ductility. In Eurocode 2, a model of confined concrete was proposed, and in the Eurocode 8 an improved model was shown. The paper also analyzes the compared values of obtained strengths and ultimate strains for both models of confined concrete, as well as their impact on the global and local seismic response in the case of a six-storey rc frame.

  17. Caught in the Net: Perineuronal Nets and Addiction

    Directory of Open Access Journals (Sweden)

    Megan Slaker


    Full Text Available Exposure to drugs of abuse induces plasticity in the brain and creates persistent drug-related memories. These changes in plasticity and persistent drug memories are believed to produce aberrant motivation and reinforcement contributing to addiction. Most studies have explored the effect drugs of abuse have on pre- and postsynaptic cells and astrocytes; however, more recently, attention has shifted to explore the effect these drugs have on the extracellular matrix (ECM. Within the ECM are unique structures arranged in a net-like manner, surrounding a subset of neurons called perineuronal nets (PNNs. This review focuses on drug-induced changes in PNNs, the molecules that regulate PNNs, and the expression of PNNs within brain circuitry mediating motivation, reward, and reinforcement as it pertains to addiction.

  18. Stress, social support and problem drinking among women in poverty. (United States)

    Mulia, Nina; Schmidt, Laura; Bond, Jason; Jacobs, Laurie; Korcha, Rachael


    Previous studies have found that stress contributes to problem drinking, while social support can buffer its effects. However, these studies are confined largely to middle-class and general populations. We extend what is known by examining how the unique stressors and forms of social support experienced by women in poverty impact alcohol problems over a 4-year time-period. This prospective study used generalized estimating equations (GEE) transition modeling and four annual waves of survey data from 392 American mothers receiving Temporary Assistance for Needy Families (TANF) in a large Northern California county. We examined the effects of neighborhood disorder, stressful life events and economic hardship on psychological distress and problem drinking over time, and whether social support moderated these relationships for women in poverty. Neighborhood disorder and stressful life events increased significantly the risk for problem drinking, largely through their effect on psychological distress. We found little evidence, however, that social support buffers poor women from the effects of these stressors. Women in poverty are exposed to severe, chronic stressors within their communities and immediate social networks which increase vulnerability to psychological distress and problem drinking. The finding that social support does not buffer stress among these women may reflect their high level of exposure to stressors, as well as the hardships and scarce resources within their networks. If the 'private safety net' of the social network fails to provide a strong buffer, more effective environmental interventions that reduce exposure to stressors may be needed to prevent alcohol problems in poor women's lives.

  19. Mechanical confinement regulates cartilage matrix formation by chondrocytes (United States)

    Lee, Hong-Pyo; Gu, Luo; Mooney, David J.; Levenston, Marc E.; Chaudhuri, Ovijit


    Cartilage tissue equivalents formed from hydrogels containing chondrocytes could provide a solution for replacing damaged cartilage. Previous approaches have often utilized elastic hydrogels. However, elastic stresses may restrict cartilage matrix formation and alter the chondrocyte phenotype. Here we investigated the use of viscoelastic hydrogels, in which stresses are relaxed over time and which exhibit creep, for three-dimensional (3D) culture of chondrocytes. We found that faster relaxation promoted a striking increase in the volume of interconnected cartilage matrix formed by chondrocytes. In slower relaxing gels, restriction of cell volume expansion by elastic stresses led to increased secretion of IL-1β, which in turn drove strong up-regulation of genes associated with cartilage degradation and cell death. As no cell-adhesion ligands are presented by the hydrogels, these results reveal cell sensing of cell volume confinement as an adhesion-independent mechanism of mechanotransduction in 3D culture, and highlight stress relaxation as a key design parameter for cartilage tissue engineering.

  20. Army Net Zero Prove Out. Army Net Zero Training Report (United States)


    sensors were strategically placed throughout the installation by magnetically attaching them to water main valve stems. The sensors check sound...Recycle Wrap  Substitutes for Packaging Materials  Re-Use of Textiles and Linens  Setting Printers to Double-Sided Printing Net Zero Waste...can effectively achieve source reduction. Clean and Re-Use Shop Rags - Shop rags represent a large textile waste stream at many installations. As a

  1. Army Net Zero Prove Out. Net Zero Waste Best Practices (United States)


    Anaerobic Digesters – Although anaerobic digestion is not a new technology and has been used on a large-scale basis in wastewater treatment , and has been used on a large-scale basis in wastewater treatment , the use of the technology should be demonstrated with other...approaches can be used for cardboard and cellulose -based packaging materials. This approach is in line with the Net Zero Waste hierarchy in terms of

  2. Characterization of Strength of Intact Brittle Rock Considering Confinement-Dependent Failure Processes (United States)

    Kaiser, Peter K.; Kim, Bo-Hyun


    As technologies for deep underground development such as tunneling underneath mountains or mass mining at great depths (>1,000 m) are implemented, more difficult ground conditions in highly stressed environments are encountered. Moreover, the anticipated stress level at these depths easily exceeds the loading capacity of laboratory testing, so it is difficult to properly characterize what the rock behavior would be under high confinement stress conditions. If rock is expected to fail in a brittle manner, behavior changes associated with the relatively low tensile strength, such as transition from splitting to the shear failure, have to be considered and reflected in the adopted failure criteria. Rock failure in tension takes place at low confinement around excavations due to tensile or extensional failure in heterogeneous rocks. The prospect of tensile-dominant brittle failure diminishes as the confinement increases away from the excavation boundary. Therefore, it must be expected that the transition in the failure mechanism, from tensile to shear, occurs as the confinement level increases and conditions for extensional failure are prevented or strongly diminished. However, conventional failure criteria implicitly consider only the shear failure mechanism (i.e., failure envelopes touching Mohr stress circles), and thus, do not explicitly capture the transition of failure modes from tensile to shear associated with confinement change. This paper examines the methodologies for intact rock strength determination as the basic input data for engineering design of deep excavations. It is demonstrated that published laboratory test data can be reinterpreted and better characterized using an s-shaped failure criterion highlighting the transition of failure modes in brittle failing rock. As a consequence of the bi-modal nature of the failure envelope, intact rock strength data are often misinterpreted. If the intact rock strength is estimated by standard procedures from

  3. Confined catalysis under two-dimensional materials (United States)

    Li, Haobo; Xiao, Jianping; Bao, Xinhe


    Confined microenvironments formed in heterogeneous catalysts have recently been recognized as equally important as catalytically active sites. Understanding the fundamentals of confined catalysis has become an important topic in heterogeneous catalysis. Well-defined 2D space between a catalyst surface and a 2D material overlayer provides an ideal microenvironment to explore the confined catalysis experimentally and theoretically. Using density functional theory calculations, we reveal that adsorption of atoms and molecules on a Pt(111) surface always has been weakened under monolayer graphene, which is attributed to the geometric constraint and confinement field in the 2D space between the graphene overlayer and the Pt(111) surface. A similar result has been found on Pt(110) and Pt(100) surfaces covered with graphene. The microenvironment created by coating a catalyst surface with 2D material overlayer can be used to modulate surface reactivity, which has been illustrated by optimizing oxygen reduction reaction activity on Pt(111) covered by various 2D materials. We demonstrate a concept of confined catalysis under 2D cover based on a weak van der Waals interaction between 2D material overlayers and underlying catalyst surfaces. PMID:28533413

  4. Stiffness and Confinement Ratios of SMA Wire Jackets for Confining Concrete (United States)

    Choi, Eunsoo; Kim, Dong Joo; Youn, Heejung


    This article discusses the effects of the stiffness and confinement ratios of shape memory alloy (SMA) wire jackets on the behavior of confined concrete. SMA wire jackets are an effective confining material to improve concrete behavior; for example, by increasing peak strength and failure strain. The stiffness and confinement ratios of fiber-reinforced polymer jackets have been extensively discussed and their effects are well known. However, assessment of the stiffness and confinement ratios of SMA wire jackets has not previously been conducted. In this study, we investigate the effects of the stiffness and confinement ratios of steel jackets, and then compare the results with those of SMA wire jackets. In general, the stiffness ratios of SMA wire jackets are relatively smaller than those of steel jackets, and most of them have lower stiffness ratios because the Young's moduli of the SMAs are relatively small. The active confining pressure of the SMA wires does not improve the lower stiffness-ratio effect since the amount of active confining pressure is not sufficiently large.

  5. Experimental and Theoretical Research on the Compression Performance of CFRP Sheet Confined GFRP Short Pipe

    Directory of Open Access Journals (Sweden)

    Feng Li


    Full Text Available The axial compressive strength of unidirectional FRP made by pultrusion is generally quite lower than its axial tensile strength. This fact decreases the advantages of FRP as main load bearing member in engineering structure. A theoretical iterative calculation approach was suggested to predict the ultimate axial compressive stress of the combined structure and analyze the influences of geometrical parameters on the ultimate axial compressive stress of the combined structure. In this paper, the experimental and theoretical research on the CFRP sheet confined GFRP short pole was extended to the CFRP sheet confined GFRP short pipe, namely, a hollow section pole. Experiment shows that the bearing capacity of the GFRP short pipe can also be heightened obviously by confining CFRP sheet. The theoretical iterative calculation approach in the previous paper is amended to predict the ultimate axial compressive stress of the CFRP sheet confined GFRP short pipe, of which the results agree with the experiment. Lastly the influences of geometrical parameters on the new combined structure are analyzed.

  6. HANPP Collection: Human Appropriation of Net Primary Productivity as a Percentage of Net Primary Productivity (United States)

    National Aeronautics and Space Administration — The Human Appropriation of Net Primary Productivity (HANPP) as a Percentage of Net Primary Productivity (NPP) portion of the Human Appropriation of Net Primary...

  7. Hydrodynamic characteristics of plane netting used for aquaculture net cages in uniform current

    National Research Council Canada - National Science Library



      The hydrodynamic characteristics of polyethylene (PE) netting and chain link wire netting with different types of twine diameter and mesh size for aquaculture net cages were examined by experiments in a flume tank...

  8. Confined Chemical Etching for Electrochemical Machining with Nanoscale Accuracy. (United States)

    Zhan, Dongping; Han, Lianhuan; Zhang, Jie; Shi, Kang; Zhou, Jian-Zhang; Tian, Zhao-Wu; Tian, Zhong-Qun


    In the past several decades, electrochemical machining (ECM) has enjoyed the reputation of a powerful technique in the manufacturing industry. Conventional ECM methods can be classified as electrolytic machining and electroforming: the former is based on anodic dissolution and the latter is based on cathodic deposition of metallic materials. Strikingly, ECM possesses several advantages over mechanical machining, such as high removal rate, the capability of making complex three-dimensional structures, and the practicability for difficult-to-cut materials. Additionally, ECM avoids tool wear and thermal or mechanical stress on machining surfaces. Thus, ECM is widely used for various industrial applications in the fields of aerospace, automobiles, electronics, etc. Nowadays, miniaturization and integration of functional components are becoming significant in ultralarge scale integration (ULSI) circuits, microelectromechanical systems (MEMS), and miniaturized total analysis systems (μ-TAS). As predicted by Moore's law, the feature size of interconnectors in ULSI circuits are down to several nanometers. In this Account, we present our perseverant research in the last two decades on how to "confine" the ECM processes to occur at micrometer or even nanometer scale, that is, to ensure ECM with nanoscale accuracy. We have been developing the confined etchant layer technique (CELT) to fabricate three-dimensional micro- and nanostructures (3D-MNS) on different metals and semiconductor materials since 1992. In general, there are three procedures in CELT: (1) generating the etchant on the surface of the tool electrode by electrochemical or photoelectrochemical reactions; (2) confining the etchant in a depleted layer with a thickness of micro- or nanometer scale; (3) feeding the tool electrode to etch the workpiece. Scavengers, which can react with the etchant, are usually adopted to form a confined etchant layer. Through the subsequent homogeneous reaction between the scavenger

  9. Inhomogeneous dynamics in confined water nanodroplets (United States)

    Dokter, Adriaan M.; Woutersen, Sander; Bakker, Huib J.


    The effect of confinement on the dynamical properties of liquid water was studied by mid-infrared ultrafast pump–probe spectroscopy on HDO:D2O in reverse micelles. By preparing water-containing reverse micelles of different well defined sizes, we varied the degree of geometric confinement in water nanodroplets with radii ranging from 0.2 to 4.5 nm. We find that water molecules located near the interface confining the droplet exhibit slower vibrational energy relaxation and have a different spectral absorption than those located in the droplet core. As a result, we can measure the orientational dynamics of these different types of water with high selectivity. We observe that the water molecules in the core show similar orientational dynamics as bulk water and that the water layer solvating the interface is highly immobile. PMID:17028175

  10. Jet characteristics in confined swirling flow (United States)

    So, R. M. C.; Ahmed, S. A.; Mongia, H. C.


    Jets in confined swirling flow are investigated in a facility where the swirling flow in the tube is produced by a vane-type swirler. The jet is located centrally in the swirler, and the diameter ratio of the tube to the jet is about 14. Both the jet and the swirling flow are fully turbulent. Results show that the confined jet is highly dissipative in nature. Consequently, the flow in the tube does not resemble a free jet with axial pressure gradient. The presence of swirl increases the rate of dissipation and the jet decays even faster. A fairly isotropic turbulence field is observed in the confined swirling flow. However, the introduction of the jet does not significantly affect this behavior, and near isotropy of the turbulence field is again observed at about 30 jet diameters downstream.

  11. Confined space facilitates G-quadruplex formation (United States)

    Shrestha, Prakash; Jonchhe, Sagun; Emura, Tomoko; Hidaka, Kumi; Endo, Masayuki; Sugiyama, Hiroshi; Mao, Hanbin


    Molecular simulations suggest that the stability of a folded macromolecule increases in a confined space due to entropic effects. However, due to the interactions between the confined molecular structure and the walls of the container, clear-cut experimental evidence for this prediction is lacking. Here, using DNA origami nanocages, we show the pure effect of confined space on the property of individual human telomeric DNA G-quadruplexes. We induce targeted mechanical unfolding of the G-quadruplex while leaving the nanocage unperturbed. We find that the mechanical and thermodynamic stabilities of the G-quadruplex inside the nanocage increase with decreasing cage size. Compared to the case of diluted or molecularly crowded buffer solutions, the G-quadruplex inside the nanocage is significantly more stable, showing a 100 times faster folding rate. Our findings suggest the possibility of co-replicational or co-transcriptional folding of G-quadruplex inside the polymerase machinery in cells.

  12. Transition metal catalysis in confined spaces. (United States)

    Leenders, Stefan H A M; Gramage-Doria, Rafael; de Bruin, Bas; Reek, Joost N H


    Transition metal catalysis plays an important role in both industry and in academia where selectivity, activity and stability are crucial parameters to control. Next to changing the structure of the ligand, introducing a confined space as a second coordination sphere around a metal catalyst has recently been shown to be a viable method to induce new selectivity and activity in transition metal catalysis. In this review we focus on supramolecular strategies to encapsulate transition metal complexes with the aim of controlling the selectivity via the second coordination sphere. As we will discuss, catalyst confinement can result in selective processes that are impossible or difficult to achieve by traditional methods. We will describe the template-ligand approach as well as the host-guest approach to arrive at such supramolecular systems and discuss how the performance of the catalyst is enhanced by confining it in a molecular container.

  13. Density shock waves in confined microswimmers

    CERN Document Server

    Tsang, Alan Cheng Hou


    Motile and driven particles confined in microfluidic channels exhibit interesting emergent behavior from propagating density bands to density shock waves. A deeper understanding of the physical mechanisms responsible for these emergent structures is relevant to a number of physical and biomedical applications. Here, we study the formation of density shock waves in the context of an idealized model of microswimmers confined in a narrow channel and subject to a uniform external flow. Interestingly, these density shock waves exhibit a transition from `subsonic' with compression at the back to `supersonic' with compression at the front of the population as the intensity of the external flow increases. This behavior is the result of a non-trivial interplay between hydrodynamic interactions and geometric confinement, and is confirmed by a novel quasilinear wave model that properly captures the dependence of the shock formation on the external flow. These findings can be used to guide the development of novel mechan...

  14. Confinement in Wendelstein 7-X limiter plasmas (United States)

    Hirsch, M.; Dinklage, A.; Alonso, A.; Fuchert, G.; Bozhenkov, S.; Höfel, U.; Andreeva, T.; Baldzuhn, J.; Beurskens, M.; Bosch, H.-S.; Beidler, C. D.; Biedermann, C.; Blanco, E.; Brakel, R.; Burhenn, R.; Buttenschön, B.; Cappa, A.; Czarnecka, A.; Endler, M.; Estrada, T.; Fornal, T.; Geiger, J.; Grulke, O.; Harris, J. H.; Hartmann, D.; Jakubowski, M.; Klinger, T.; Knauer, J.; Kocsis, G.; König, R.; Kornejew, P.; Krämer-Flecken, A.; Krawczyk, N.; Krychowiak, M.; Kubkowska, M.; Ksiazek, I.; Langenberg, A.; Laqua, H. P.; Lazerson, S.; Maaßberg, H.; Marushchenko, N.; Marsen, S.; Moncada, V.; Moseev, D.; Naujoks, D.; Otte, M.; Pablant, N.; Pasch, E.; Pisano, F.; Rahbarnia, K.; Schröder, T.; Stange, T.; Stephey, L.; Szepesi, T.; Pedersen, T. Sunn; Trimino Mora, H.; Thomsen, H.; Tsuchiya, H.; Turkin, Yu.; Wauters, T.; Weir, G.; Wenzel, U.; Werner, A.; Wolf, R.; Wurden, G. A.; Zhang, D.; the W7-X Team


    Observations on confinement in the first experimental campaign on the optimized Stellarator Wendelstein 7-X are summarized. In this phase W7-X was equipped with five inboard limiters only and thus the discharge length restricted to avoid local overheating. Stationary plasmas are limited to low densities  <2-3 · 1019 m-3. With the available 4.3 MW ECR Heating core T e ~ 8 keV, T i ~ 1-2 keV are achieved routinely resulting in energy confinement time τ E between 80 ms to 150 ms. For these conditions the plasmas show characteristics of core electron root confinement with peaked T e-profiles and positive E r up to about half of the minor radius. Profiles and plasma currents respond to on- and off-axis heating and co- and counter ECCD respectively.

  15. Clays in natural and engineered barriers for radioactive waste confinement

    Energy Technology Data Exchange (ETDEWEB)



    The meeting covers all topics concerning natural argillaceous geological barriers and the clay material based engineered barrier systems, investigated by means of: laboratory experiments on clay samples (new analytical developments), in situ experiments in underground research laboratories, mock-up demonstrations, natural analogues, as well as numerical modelling and global integration approaches (including up-scaling processes and treatment of uncertainties). The works presented deal with: examples of broad research programs (national or international) on the role of natural and artificial clay barriers for radionuclide confinement; clay-based repository concepts: repository designs, including technological and safety issues related to the use of clay for nuclear waste confinement; geology and clay characterisation: mineralogy, sedimentology, paleo-environment, diagenesis, dating techniques, discontinuities in rock clay, fracturing, self sealing processes, role of organic matter and microbiological processes; geochemistry: pore water geochemistry, clay thermodynamics, chemical retention, geochemical modelling, advanced isotopic geochemistry; mass transfer: water status and hydraulic properties in low permeability media, pore space geometry, water, solute and gas transfer processes, colloid mediated transport, large scale movements, long-term diffusion; alteration processes: oxidation effects, hydration-dehydration processes, response to thermal stress, iron-clay interactions, alkaline perturbation; geomechanics: thermo-hydro-mechanical behaviour of clay, rheological models, EDZ characterisation and evolution, coupled behaviour and models (HM, THM, THMC). A particular interest is given to potential contributions coming from fields of activities other than radioactive waste management, which take advantage of the confinement properties of the clay barrier (oil and gas industries, gas geological storage, CO{sub 2} geological sequestration, chemical waste isolation

  16. Isolated unit tests in .Net


    Haukilehto, Tero


    In this thesis isolation in unit testing is studied to get a precise picture of the isolation frameworks available for .Net environment. At the beginning testing is discussed in theory with the benefits and the problems it may have been linked with. The theory includes software development in general in connection with testing. Theory of isolation is also described before the actual isolation frameworks are represented. Common frameworks are described in more detail and comparable informa...

  17. A new model of gluon confinement

    Energy Technology Data Exchange (ETDEWEB)

    Novello, M.; De Lorenci, V.A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Elbaz, E. [Universite Claude Bernard, 69 - Lyon (France). Inst. de Physique Nucleaire


    In this paper we present a model for the dynamics of a gauge field theory such that spin-one particles can be confined in a compact domain. We show that the property of confinement can be associated to the formation of a null surface identified to a horizon. This is due the presence of an effective geometry generated by the self-interaction of the gauge field that guides the wave propagation of the field. This phenomenon has a striking analog to the gravitational back hole in Einstein general theory of relativity, separating two domains of spacetime that can be trespassed only into one direction. (author) 4 refs., 1 fig.

  18. Molecular reactivity dynamics in a confined environment. (United States)

    Khatua, Munmun; Chattaraj, Pratim Kumar


    Time evolution of various reactivity parameters viz. hardness, electrophilicity, chemical potential, polarizability, etc. in a confined environment has been studied through quantum fluid density functional theory formalism during time dependent processes such as proton-molecule collisions and molecule-field interaction. A Dirichlet type boundary condition has been incorporated to confine the systems. Responses in the reactivity parameters of the diatomic molecules, in the dynamical context, in ground state as well as in excited state, have been reported. Harmonic spectra are generated in the cases of the external laser field interacting with H2 and N2 molecules.

  19. Confinement Effect on Material Properties of RC Beams Under Flexure (United States)

    Kulkarni, Sumant; Shiyekar, Mukund Ramchandra; Shiyekar, Sandip Mukund


    In structural analysis, especially in indeterminate structures, it becomes essential to know the material and geometrical properties of members. The codal provisions recommend elastic properties of concrete and steel and these are fairly accurate enough. The stress-strain curve for concrete cylinder or a cube specimen is plotted. The slope of this curve is modulus of elasticity of plain concrete. Another method of determining modulus of elasticity of concrete is by flexural test of a beam specimen. The modulus of elasticity most commonly used for concrete is secant modulus. The modulus of elasticity of steel is obtained by performing a tension test of steel bar. While performing analysis by any software for high rise building, cross area of plain concrete is taken into consideration whereas effects of reinforcement bars and concrete confined by stirrups are neglected. Present aim of study is to determine elastic properties of reinforced cement concrete beam. Two important stiffness properties such as AE and EI play important role in analysis of high rise RCC building idealized as plane frame. The experimental program consists of testing of beams (model size 150 × 150 × 700 mm) with percentage of reinforcement varying from 0.54 to 1.63% which commensurate with existing Codal provisions of IS:456-2000 for flexural member. The effect of confinement is considered in this study. The experimental results are verified by using 3D finite element techniques.

  20. Confinement Effect on Material Properties of RC Beams Under Flexure (United States)

    Kulkarni, Sumant; Shiyekar, Mukund Ramchandra; Shiyekar, Sandip Mukund


    In structural analysis, especially in indeterminate structures, it becomes essential to know the material and geometrical properties of members. The codal provisions recommend elastic properties of concrete and steel and these are fairly accurate enough. The stress-strain curve for concrete cylinder or a cube specimen is plotted. The slope of this curve is modulus of elasticity of plain concrete. Another method of determining modulus of elasticity of concrete is by flexural test of a beam specimen. The modulus of elasticity most commonly used for concrete is secant modulus. The modulus of elasticity of steel is obtained by performing a tension test of steel bar. While performing analysis by any software for high rise building, cross area of plain concrete is taken into consideration whereas effects of reinforcement bars and concrete confined by stirrups are neglected. Present aim of study is to determine elastic properties of reinforced cement concrete beam. Two important stiffness properties such as AE and EI play important role in analysis of high rise RCC building idealized as plane frame. The experimental program consists of testing of beams (model size 150 × 150 × 700 mm) with percentage of reinforcement varying from 0.54 to 1.63% which commensurate with existing Codal provisions of IS:456-2000 for flexural member. The effect of confinement is considered in this study. The experimental results are verified by using 3D finite element techniques.

  1. Event hierarchies in DanNet

    DEFF Research Database (Denmark)

    Pedersen, Bolette Sandford; Nimb, Sanni


    Artiklen omhandler udarbejdelsen af et verbumshierarki i det leksikalsk-semantiske ordnet, DanNet.......Artiklen omhandler udarbejdelsen af et verbumshierarki i det leksikalsk-semantiske ordnet, DanNet....

  2. The Uniframe .Net Web Service Discovery Service

    National Research Council Canada - National Science Library

    Berbeco, Robert W


    Microsoft .NET allows the creation of distributed systems in a seamless manner Within NET small, discrete applications, referred to as Web services, are utilized to connect to each other or larger applications...

  3. Long Term RadNet Quality Data (United States)

    U.S. Environmental Protection Agency — This RadNet Quality Data Asset includes all data since initiation and when ERAMS was expanded to become RadNet, name changed to reflect new mission. This includes...

  4. Fusion energy in an inertial electrostatic confinement device using a magnetically shielded grid

    Energy Technology Data Exchange (ETDEWEB)

    Hedditch, John, E-mail:; Bowden-Reid, Richard, E-mail:; Khachan, Joe, E-mail: [School of Physics, The University of Sydney, Sydney, New South Whales 2006 (Australia)


    Theory for a gridded inertial electrostatic confinement (IEC) fusion system is presented, which shows a net energy gain is possible if the grid is magnetically shielded from ion impact. A simplified grid geometry is studied, consisting of two negatively biased coaxial current-carrying rings, oriented such that their opposing magnetic fields produce a spindle cusp. Our analysis indicates that better than break-even performance is possible even in a deuterium-deuterium system at bench-top scales. The proposed device has the unusual property that it can avoid both the cusp losses of traditional magnetic fusion systems and the grid losses of traditional IEC configurations.

  5. Fusion in a magnetically-shielded-grid inertial electrostatic confinement device

    CERN Document Server

    Hedditch, John; Khachan, Joe


    Theory for a gridded inertial electrostatic confinement (IEC) fusion system is presented that shows a net energy gain is possible if the grid is magnetically shielded from ion impact. A simplified grid geometry is studied, consisting of two negatively-biased coaxial current-carrying rings, oriented such that their opposing magnetic fields produce a spindle cusp. Our analysis indicates that better than break-even performance is possible even in a deuterium-deuterium system at bench-top scales. The proposed device has the unusual property that it can avoid both the cusp losses of traditional magnetic fusion systems and the grid losses of traditional IEC configurations.

  6. PsychoNet: a psycholinguistc commonsense ontology


    Mohtasseb, Haytham; Ahmed, Amr


    Ontologies have been widely accepted as the most advanced knowledge representation model. This paper introduces PsychoNet, a new knowledgebase that forms the link between psycholinguistic taxonomy, existing in LIWC, and its semantic textual representation in the form of commonsense semantic ontology, represented by ConceptNet. The integration of LIWC and ConceptNet and the added functionalities facilitate employing ConceptNet in psycholinguistic studies. Furthermore, it simplifies utilization...

  7. Confinement of light in a polarizable vacuum

    Directory of Open Access Journals (Sweden)

    Avinash Khare


    Full Text Available We show that an electrically polarizable vacuum with space-dependent permeability ε(r = μ−1(rexp(−αr2 can confine light whose quanta acquire a mass through interaction with this vacuum.

  8. Modulus-Pressure Equation for Confined Fluids

    CERN Document Server

    Gor, Gennady Y; Shen, Vincent K; Bernstein, Noam


    Ultrasonic experiments allow one to measure the elastic modulus of bulk solid or fluid samples. Recently such experiments have been carried out on fluid-saturated nanoporous glass to probe the modulus of a confined fluid. In our previous work [J. Chem. Phys., (2015) 143, 194506], using Monte Carlo simulations we showed that the elastic modulus $K$ of a fluid confined in a mesopore is a function of the pore size. Here we focus on modulus-pressure dependence $K(P)$, which is linear for bulk materials, a relation known as the Tait-Murnaghan equation. Using transition-matrix Monte Carlo simulations we calculated the elastic modulus of bulk argon as a function of pressure and argon confined in silica mesopores as a function of Laplace pressure. Our calculations show that while the elastic modulus is strongly affected by confinement and temperature, the slope of the modulus versus pressure is not. Moreover, the calculated slope is in a good agreement with the reference data for bulk argon and experimental data for ...

  9. Non-resonant Nanoscale Extreme Light Confinement

    Energy Technology Data Exchange (ETDEWEB)

    Subramania, Ganapathi Subramanian [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Huber, Dale L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    A wide spectrum of photonics activities Sandia is engaged in such as solid state lighting, photovoltaics, infrared imaging and sensing, quantum sources, rely on nanoscale or ultrasubwavelength light-matter interactions (LMI). The fundamental understanding in confining electromagnetic power and enhancing electric fields into ever smaller volumes is key to creating next generation devices for these programs. The prevailing view is that a resonant interaction (e.g. in microcavities or surface-plasmon polaritions) is necessary to achieve the necessary light confinement for absorption or emission enhancement. Here we propose new paradigm that is non-resonant and therefore broadband and can achieve light confinement and field enhancement in extremely small areas [~(λ/500)^2 ]. The proposal is based on a theoretical work[1] performed at Sandia. The paradigm structure consists of a periodic arrangement of connected small and large rectangular slits etched into a metal film named double-groove (DG) structure. The degree of electric field enhancement and power confinement can be controlled by the geometry of the structure. The key operational principle is attributed to quasistatic response of the metal electrons to the incoming electromagnetic field that enables non-resonant broadband behavior. For this exploratory LDRD we have fabricated some test double groove structures to enable verification of quasistatic electronic response in the mid IR through IR optical spectroscopy. We have addressed some processing challenges in DG structure fabrication to enable future design of complex sensor and detector geometries that can utilize its non-resonant field enhancement capabilities.].

  10. Enhanced heat transfer in confined pool boiling

    NARCIS (Netherlands)

    Rops, C.M.; Lindken, R.; Velthuis, J.F.M.; Westerweel, J.


    We report the results of an experimental investigation of the heat transfer during nucleate boiling on a spatially confined boiling surface. The heat flux as a function of the boiling surface temperature was measured in pool boiling pots with diameters ranging from 15 mm down to 4.5 mm. It was found

  11. Mesoscale simulations of confined Nafion thin films (United States)

    Vanya, P.; Sharman, J.; Elliott, J. A.


    The morphology and transport properties of thin films of the ionomer Nafion, with thicknesses on the order of the bulk cluster size, have been investigated as a model system to explain the anomalous behaviour of catalyst/electrode-polymer interfaces in membrane electrode assemblies. We have employed dissipative particle dynamics (DPD) to investigate the interaction of water and fluorocarbon chains, with carbon and quartz as confining materials, for a wide range of operational water contents and film thicknesses. We found confinement-induced clustering of water perpendicular to the thin film. Hydrophobic carbon forms a water depletion zone near the film interface, whereas hydrophilic quartz results in a zone with excess water. There are, on average, oscillating water-rich and fluorocarbon-rich regions, in agreement with experimental results from neutron reflectometry. Water diffusivity shows increasing directional anisotropy of up to 30% with decreasing film thickness, depending on the hydrophilicity of the confining material. A percolation analysis revealed significant differences in water clustering and connectivity with the confining material. These findings indicate the fundamentally different nature of ionomer thin films, compared to membranes, and suggest explanations for increased ionic resistances observed in the catalyst layer.

  12. Subwavelength light confinement with surface plasmon polaritons

    NARCIS (Netherlands)

    Verhagen, E.


    In free space, the diffraction limit sets a lower bound to the size to which light can be confined. Surface plasmon polaritons (SPPs), which are electromagnetic waves bound to the interface between a metal and a dielectric, allow the control of light on subwavelength length scales. This opens up a

  13. Structure of polymer chains under confinement

    Indian Academy of Sciences (India)

    Abstract. We observe by SANS the structure of neutral polystyrene and charged polystyrene sulphonate chains in semi-dilute solutions confined in a model nanoporous glass, Vycor. The size of the free chains in solution is always larger than the pore di- ameter, 70. The use of a suitable mixture of hydrogenated and ...

  14. Clusters of polyhedra in spherical confinement (United States)

    Teich, Erin G.; van Anders, Greg; Klotsa, Daphne; Dshemuchadse, Julia; Glotzer, Sharon C.


    Dense particle packing in a confining volume remains a rich, largely unexplored problem, despite applications in blood clotting, plasmonics, industrial packaging and transport, colloidal molecule design, and information storage. Here, we report densest found clusters of the Platonic solids in spherical confinement, for up to N=60 constituent polyhedral particles. We examine the interplay between anisotropic particle shape and isotropic 3D confinement. Densest clusters exhibit a wide variety of symmetry point groups and form in up to three layers at higher N. For many N values, icosahedra and dodecahedra form clusters that resemble sphere clusters. These common structures are layers of optimal spherical codes in most cases, a surprising fact given the significant faceting of the icosahedron and dodecahedron. We also investigate cluster density as a function of N for each particle shape. We find that, in contrast to what happens in bulk, polyhedra often pack less densely than spheres. We also find especially dense clusters at so-called magic numbers of constituent particles. Our results showcase the structural diversity and experimental utility of families of solutions to the packing in confinement problem. PMID:26811458

  15. Confined surface plasmons in gold photonic nanocavities

    Energy Technology Data Exchange (ETDEWEB)

    Netti, C.; Coyle, S.; Baumberg, J.J. [Southampton Univ. (United Kingdom). Dept. of Physics and Astronomy; Ghanem, M.A.; Birkin, P.R.; Bartlett, P.N. [Southampton Univ. (United Kingdom). Dept. of Chemistry; Whittaker, D.M. [Toshiba Research Europe Ltd., Cambridge (United Kingdom)


    A simple scheme to produce large-area colored metal surfaces by completely confining surface plasmons inside gold spherical nanocavities has been discovered. The negative nanocavity curvature localizes the electromagnetic fields into small volumes, which can be arranged non-periodically. (orig.)

  16. Spinal cord compression following traditional confinement massage. (United States)

    Sahathevan, R; Tan, H J; Abdullah, Suhail; Shahizon, A M M; Hamidon, B B; Raymond, A A


    We describe a case of tetraparesis in a 33-year-old woman following neck manipulation performed by a traditional confinement mid-wife. An MRI of the cervical spine revealed a fracture of the second cervical vertebra with atlanto-axial subluxation that resulted in cord compression.

  17. Capillary breakup of fluid threads within confinement (United States)

    Hu, Guoqing; Xue, Chundong; Chen, Xiaodong


    Fluid thread breakup is a widespread phenomenon in nature, industry, and daily life. Driven by surface tension (or capillarity) at low flow-rate condition, the breakup scenario is usually called capillary instability or Plateau-Rayleigh instability. Fluid thread deforms under confinement of ambient fluid to form a fluid neck. Thinning of the neck at low flow-rate condition is quasistatic until the interface becomes unstable and collapses to breakup. Underlying mechanisms and universalities of both the stable and unstable thinning remain, however, unclear and even contradictory. Here we conduct new numerical and experimental studies to show that confined interfaces are not only stabilized but also destabilized by capillarity at low flow-rate condition. Capillary stabilization is attributed to confinement-determined internal pressure that is higher than capillary pressure along the neck. Two origins of capillary destabilization are identified: one is confinement-induced gradient of capillary pressure along the interface; the other is the competition between local capillary pressure and internal pressure. This work was supported by National Natural Science Foundation of China (Grant No. 11402274, 11272321, and 11572334).

  18. Ultrafast chemistry in complex and confined systems

    Indian Academy of Sciences (India)

    Self-organized molecular assemblies play a crucial role in many natural and biological processes. Recent applications of ultrafast laser spectroscopy and computer simulations revealed that chemistry in a confined environment is fundamentally different from that in ordinary solutions. Many recent examples of slow dynamics ...

  19. The theory of delamination during drying of confined colloidal suspensions. (United States)

    Wallenstein, K J; Russel, W B


    Recent experiments on the drying of colloidal films in confined thin rectangular geometries show an interesting new phenomenon: the delamination of the colloidal suspension from the cavity wall. The theory developed in this paper explains the phenomenon by applying the Griffith energy criteria to a poroelastic film of Hertzian spheres. Prior to delamination, flow due to drying compresses the film in the direction of flow and generates tension in the transverse direction. Delamination allows relaxation in both the transverse tensile stresses and the axial compression. Preliminary numerical solutions suggest that the elastic energy recovered should increase linearly with the length of the close-packed film. That suggests a simple analytical solution that predicts the advancing of the delamination as the length of the close-packed region increases and explains qualitatively the essential features of the phenomenon.

  20. 78 FR 72451 - Net Investment Income Tax (United States)


    ... Revenue Service 26 CFR Part 1 RIN 1545-BL74 Net Investment Income Tax AGENCY: Internal Revenue Service...). These regulations provide guidance on the computation of net investment income. The regulations affect... lesser of: (A) The individual's net investment income for such taxable year, or (B) the excess (if any...

  1. 47 CFR 69.302 - Net investment. (United States)


    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Net investment. 69.302 Section 69.302... Apportionment of Net Investment § 69.302 Net investment. (a) Investment in Accounts 2001, 1220 and Class B Rural...) Investment in Accounts 2002, 2003 and to the extent such inclusions are allowed by this Commission, Account...

  2. 47 CFR 65.450 - Net income. (United States)


    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Net income. 65.450 Section 65.450... OF RETURN PRESCRIPTION PROCEDURES AND METHODOLOGIES Exchange Carriers § 65.450 Net income. (a) Net income shall consist of all revenues derived from the provision of interstate telecommunications services...

  3. 47 CFR 65.500 - Net income. (United States)


    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Net income. 65.500 Section 65.500... OF RETURN PRESCRIPTION PROCEDURES AND METHODOLOGIES Interexchange Carriers § 65.500 Net income. The net income methodology specified in § 65.450 shall be utilized by all interexchange carriers that are...

  4. NetBeans IDE 8 cookbook

    CERN Document Server

    Salter, David


    If you're a Java developer of any level using NetBeans and want to learn how to get the most out of NetBeans, then this book is for you. Learning how to utilize NetBeans will provide a firm foundation for your Java application development.

  5. Characterizing behavioural congruences for Petri nets

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Priese, Lutz; Sassone, Vladimiro


    We exploit a notion of interface for Petri nets in order to design a set of net combinators. For such a calculus of nets, we focus on the behavioural congruences arising from four simple notions of behaviour, viz., traces, maximal traces, step, and maximal step traces, and from the corresponding...

  6. 27 CFR 4.37 - Net contents. (United States)


    ... the volume of wine within the container, except that the following tolerances shall be allowed: (1... THE TREASURY LIQUORS LABELING AND ADVERTISING OF WINE Labeling Requirements for Wine § 4.37 Net contents. (a) Statement of net contents. The net contents of wine for which a standard of fill is...

  7. Confined Water: Structure, Dynamics, and Thermodynamics. (United States)

    Chakraborty, Sudip; Kumar, Hemant; Dasgupta, Chandan; Maiti, Prabal K


    Understanding the properties of strongly confined water is important for a variety of applications such as fast flow and desalination devices, voltage generation, flow sensing, and nanofluidics. Confined water also plays an important role in many biological processes such as flow through ion channels. Water in the bulk exhibits many unusual properties that arise primarily from the presence of a network of hydrogen bonds. Strong confinement in structures such as carbon nanotubes (CNTs) substantially modifies the structural, thermodynamic, and dynamic (both translational and orientational) properties of water by changing the structure of the hydrogen bond network. In this Account, we provide an overview of the behavior of water molecules confined inside CNTs and slit pores between graphene and graphene oxide (GO) sheets. Water molecules confined in narrow CNTs are arranged in a single file and exhibit solidlike ordering at room temperature due to strong hydrogen bonding between nearest-neighbor molecules. Although molecules constrained to move along a line are expected to exhibit single-file diffusion in contrast to normal Fickian diffusion, we show, from a combination of molecular dynamics simulations and analytic calculations, that water molecules confined in short and narrow CNTs with open ends exhibit Fickian diffusion because of their collective motion as a single unit due to strong hydrogen bonding. Confinement leads to strong anisotropy in the orientational relaxation of water molecules. The time scale of relaxation of the dipolar correlations of water molecules arranged in a single file becomes ultraslow, of the order of several nanoseconds, compared with the value of 2.5 ps for bulk water. In contrast, the relaxation of the vector that joins the two hydrogens in a water molecule is much faster, with a time scale of about 150 fs, which is about 10 times shorter than the corresponding time scale for bulk water. This is a rare example of confinement leading to

  8. NET 40 Generics Beginner's Guide

    CERN Document Server

    Mukherjee, Sudipta


    This is a concise, practical guide that will help you learn Generics in .NET, with lots of real world and fun-to-build examples and clear explanations. It is packed with screenshots to aid your understanding of the process. This book is aimed at beginners in Generics. It assumes some working knowledge of C# , but it isn't mandatory. The following would get the most use out of the book: Newbie C# developers struggling with Generics. Experienced C++ and Java Programmers who are migrating to C# and looking for an alternative to other generic frameworks like STL and JCF would find this book handy.

  9. The Net Reclassification Index (NRI)

    DEFF Research Database (Denmark)

    Pepe, Margaret S.; Fan, Jing; Feng, Ziding


    The Net Reclassification Index (NRI) is a very popular measure for evaluating the improvement in prediction performance gained by adding a marker to a set of baseline predictors. However, the statistical properties of this novel measure have not been explored in depth. We demonstrate the alarming...... marker is proven to erroneously yield a positive NRI. Some insight into this phenomenon is provided. Since large values for the NRI statistic may simply be due to use of poorly fitting risk models, we suggest caution in using the NRI as the basis for marker evaluation. Other measures of prediction...

  10. Cyclic Experimental Studies on Damage Evolution Behaviors of Shale Dependent on Structural Orientations and Confining Pressures

    Directory of Open Access Journals (Sweden)

    Cheng Cheng


    Full Text Available Damage process of shale is of great importance when considering the wellbore stability and reservoir stimulation during the work of shale gas recovery. As shale has typical transversely isotropic structures and may be under different stress states in the reservoir, the damage process should be studied while considering both loading directions and confining pressures. A series of cyclic uniaxial and tri-axial compressive tests have been carried out on the shale samples with different oriented weak planes and confining pressures. The dissipated strain energy and its ratio to the releasable elastic strain energy have been studied comparing with the fracturing patterns of the samples. Based on the strain energy dissipation, damage variable is defined and the damage evolution equation is built to describe the damage process of shale samples dependent on loading directions and confining pressures. The damage equation shows that the damage of the shale samples increases as a power function of the axial stress. Under higher confining pressures, the damage is limited in the early loading stage, while it increases significantly with the formation of macro shear fractures when the peak strength is approaching. The change of increasing rate is weak for the shale samples (β = 60° as the main failure pattern is slip along the weak planes. This study is helpful for understanding the damage process and failure of wellbore, as well as the stimulation effect of the shale gas reservoir.

  11. Structural behavior of supercritical fluids under confinement (United States)

    Ghosh, Kanka; Krishnamurthy, C. V.


    The existence of the Frenkel line in the supercritical regime of a Lennard-Jones (LJ) fluid shown through molecular dynamics (MD) simulations initially and later corroborated by experiments on argon opens up possibilities of understanding the structure and dynamics of supercritical fluids in general and of the Frenkel line in particular. The location of the Frenkel line, which demarcates two distinct physical states, liquidlike and gaslike within the supercritical regime, has been established through MD simulations of the velocity autocorrelation (VACF) and radial distribution function (RDF). We, in this article, explore the changes in the structural features of supercritical LJ fluid under partial confinement using atomistic walls. The study is carried out across the Frenkel line through a series of MD simulations considering a set of thermodynamics states in the supercritical regime (P =5000 bar, 240 K ≤T ≤1500 K ) of argon well above the critical point. Confinement is partial, with atomistic walls located normal to z and extending to "infinity" along the x and y directions. In the "liquidlike" regime of the supercritical phase, particles are found to be distributed in distinct layers along the z axis with layer spacing less than one atomic diameter and the lateral RDF showing amorphous-like structure for specific spacings (packing frustration) and non-amorphous-like structure for other spacings. Increasing the rigidity of the atomistic walls is found to lead to stronger layering and increased structural order. For confinement with reflective walls, layers are found to form with one atomic diameter spacing and the lateral RDF showing close-packed structure for the smaller confinements. Translational order parameter and excess entropy assessment confirms the ordering taking place for atomistic wall and reflective wall confinements. In the "gaslike" regime of the supercritical phase, particle distribution along the spacing and the lateral RDF exhibit features

  12. Extra-dimensional confinement of quantum particles

    CERN Document Server

    Hedin, Eric R


    A basic theoretical framework is developed in which elementary particles have a component of their wave function extending into higher spatial dimensions. This model postulates an extension of the Schrodinger equation to include a 4th and 5th spatial component. A higher-dimensional simple harmonic oscillator confining potential localizes particles into 3-d space, characterizing the brane tension which confines Standard Model particles to the sub-manifold. Quantum effects allow a non-zero probability for a particle's evanescent existence in the higher dimensions, and suggest an experimental test for the validity of this model via particles being temporarily excited into the first excited state of the extra-dimensional potential well, in which their probability of existing in 3-d space transiently drops to zero. Several consistency checks of the outcomes of this extra-dimensional model are included in this paper. Among the outcomes of this model are: a match with the quantum phenomenon of zitterbewegung; the pr...

  13. Influence of confining layers' heterogeneity on the barometric response functions in semi-confined aquifers (United States)

    Redaelli, Marco; Perulero Serrano, Raul


    It has been shown that Barometric Response Functions (BRFs) can provide a useful tool for detecting the occurrence of highly conducive bodies which span across aquifer confining layers and can potentially give rise to pathways for pollutant migration (Hussein et al 2013, Odling et al 2015). Analytical models employed to estimate BRFs from geological system properties assume homogeneity within the aquifer and its confining layer. These assumptions are rarely satisfied in practice. Our study focusses on the impact on predicted BRFs of heterogeneous distribution of high conductivity geomaterials within the confining layer. The work is grounded on a suite of three-dimensional, transient numerical computations of groundwater flow in a confining layer-aquifer system for i) a perfectly homogeneous two-layer setting where a single highly conducive block is fully penetrating the confining layer and ii) a heterogeneous two-layer system where hydraulic conductivity in the confining layer is modelled as a stochastic process. Our numerical results are interpreted through a comparison against those associated with an analytical model which assumes system homogeneity. Monitoring points located in the middle of the modelled aquifer domain, mimicking screened boreholes in field conditions, are used to extract water level records. The output is used to obtain the corresponding BRFs (in terms of gain and phase components) and compared vis-a-vis the selected analytical solution. The results show a wide variety of BRF responses, especially in the gain component, which vary from almost confined to unconfined scenarios. Our simulations show that the BRFs are a viable tool to improve understanding of the degree of spatial continuity within low permeability heterogeneous geological materials such as glacial till which is frequently found overlying water bearing units across the UK and other localities worldwide. As such, it has the potential to improve groundwater vulnerability assessment

  14. Scanning gate imaging in confined geometries


    Steinacher, R.; Kozikov, A. A.; Rössler, C.; Reichl, C.; Wegscheider, W.; Ensslin, K.; Ihn, T.


    This article reports on tunable electron backscattering investigated with the biased tip of a scanning force microscope. Using a channel defined by a pair of Schottky gates, the branched electron flow of ballistic electrons injected from a quantum point contact is guided by potentials of a tunable height well below the Fermi energy. The transition from injection into an open two-dimensional electron gas to a strongly confined channel exhibits three experimentally distinct regimes: one in whic...

  15. Confinement in anti-de Sitter space (United States)

    Aharony, Ofer; Berkooz, Micha; Tong, David; Yankielowicz, Shimon


    Four dimensional gauge theories in anti-de Sitter space, including pure Yang-Mills theory, exhibit a quantum phase transition between a deconfined phase and a confined phase as the gauge coupling is varied. We explore various mechanisms by which this may occur, both in a fixed background and in the presence of gravity. We also make a number of observations on the dynamics of four dimensional supersymmetric gauge theories in anti-de Sitter space.

  16. A dynamical model for plasma confinement transitions (United States)

    Pilarczyk, Paweł; García, Luis; Carreras, Benjamin A.; Llerena, Irene


    A three-equation model describing the evolution of the turbulence level, averaged shear flow and sheared zonal flow is analyzed using topological properties of the asymptotic solutions. An exploration in parameter space is done, identifying the attractor sets, which are fixed points and limit cycles. Then a more detailed analysis of all Morse sets is conducted using topological-combinatorial computations. This model allows the description of different types of transitions to improved plasma confinement regimes.

  17. Rheology of Confined Non-Brownian Suspensions. (United States)

    Fornari, Walter; Brandt, Luca; Chaudhuri, Pinaki; Lopez, Cyan Umbert; Mitra, Dhrubaditya; Picano, Francesco


    We study the rheology of confined suspensions of neutrally buoyant rigid monodisperse spheres in plane-Couette flow using direct numerical simulations. We find that if the width of the channel is a (small) integer multiple of the sphere diameter, the spheres self-organize into two-dimensional layers that slide on each other and the effective viscosity of the suspension is significantly reduced. Each two-dimensional layer is found to be structurally liquidlike but its dynamics is frozen in time.

  18. Engineered barriers for radioactive waste confinement


    Fernández, R


    Nuclear power plants generate long-lived radioactive waste of high toxicity. The security assessment of repositories destined to definitive confinement of radioactive waste has been studied for several decades. Deep geological repositories are technically feasible and begin to be built by some pioneer countries. The scientific evaluation of interactions between the different engineered barriers is studied by laboratory experiments, natural analogues and modeling studies. The three methods are...

  19. The functionality-based application confinement model


    Schreuders, ZC; Payne, C.; Mcgill, T.


    This paper presents the functionality-based application confinement (FBAC) access control model. FBAC is an application-oriented access control model, intended to restrict processes to the behaviour that is authorised by end users, administrators, and processes, in order to limit the damage that can be caused by malicious code, due to software vulnerabilities or malware. FBAC is unique in its ability to limit applications to finely grained access control rules based on high-level easy-to-unde...

  20. Spectral confinement and current for atoms in strong magnetic fields

    DEFF Research Database (Denmark)

    Fournais, Søren


    e study confinement of the ground state of atoms in strong magnetic fields to different subspaces related to the lowest Landau band. Using the results on confinement we can calculate the quantum current in the entire semiclassical region B<3......e study confinement of the ground state of atoms in strong magnetic fields to different subspaces related to the lowest Landau band. Using the results on confinement we can calculate the quantum current in the entire semiclassical region B

  1. Radiolysis of confined water: molecular hydrogen formation

    Energy Technology Data Exchange (ETDEWEB)

    Rotureau, P.; Renault, J.P.; Mialocq, J.C. [CEA/Saclay, DSM/DRECAM/SCM/URA 331 CNRS, 91191 Gif-sur-Yvette Cedex (France); Lebeau, B.; Patarin, J. [Laboratoire de Materiaux a Porosite Controlee, UMR CNRS 7016, ENSCMu-UHA, 3, Rue Alfred Werner, 68093 Mulhouse Cedex (France)


    The formation of molecular hydrogen in the radiolysis of water confined in nanoscale pores of well-characterised porous silica glasses and mesoporous molecular sieves (MCM-41) is examined. The comparison of dihydrogen formation by irradiation of both materials, dry and hydrated, shows that a large part of the H{sub 2} comes from the surface of the material. The radiolytic yields, G(H{sub 2})=(3{+-}0.5) x 10{sup -7} mol J{sup -1}, calculated using the total energy deposited in the material and the water, are only slightly affected by the degree of hydration of the material and by the pore size. These yields are also not modified by the presence of hydroxyl radical scavengers. This observation proves that the back reaction between H{sub 2} and HO{sup .} is inoperative in such confined environments. Furthermore, the large amount of H{sub 2} produced in the presence of different concentrated scavengers of the hydrated electron and its precursor suggests that these two species are far from being the only species responsible for the H{sub 2} formation. Our results show that the radiolytic phenomena that occur in water confined in nanoporous silica are dramatically different to those in bulk water, suggesting the need to investigate further the chemical reactivity in this type of environment. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  2. Radiolysis of confined water: molecular hydrogen formation. (United States)

    Rotureau, P; Renault, J P; Lebeau, B; Patarin, J; Mialocq, J-C


    The formation of molecular hydrogen in the radiolysis of water confined in nanoscale pores of well-characterised porous silica glasses and mesoporous molecular sieves (MCM-41) is examined. The comparison of dihydrogen formation by irradiation of both materials, dry and hydrated, shows that a large part of the H2 comes from the surface of the material. The radiolytic yields, G(H2)=(3+/-0.5)x10(-7) mol J(-1), calculated using the total energy deposited in the material and the water, are only slightly affected by the degree of hydration of the material and by the pore size. These yields are also not modified by the presence of hydroxyl radical scavengers. This observation proves that the back reaction between H2 and HO(.) is inoperative in such confined environments. Furthermore, the large amount of H2 produced in the presence of different concentrated scavengers of the hydrated electron and its precursor suggests that these two species are far from being the only species responsible for the H2 formation. Our results show that the radiolytic phenomena that occur in water confined in nanoporous silica are dramatically different to those in bulk water, suggesting the need to investigate further the chemical reactivity in this type of environment.

  3. Chemical reactions confined within carbon nanotubes. (United States)

    Miners, Scott A; Rance, Graham A; Khlobystov, Andrei N


    In this critical review, we survey the wide range of chemical reactions that have been confined within carbon nanotubes, particularly emphasising how the pairwise interactions between the catalysts, reactants, transition states and products of a particular molecular transformation with the host nanotube can be used to control the yields and distributions of products of chemical reactions. We demonstrate that nanoscale confinement within carbon nanotubes enables the control of catalyst activity, morphology and stability, influences the local concentration of reactants and products thus affecting equilibria, rates and selectivity, pre-arranges the reactants for desired reactions and alters the relative stability of isomeric products. We critically evaluate the relative advantages and disadvantages of the confinement of chemical reactions inside carbon nanotubes from a chemical perspective and describe how further developments in the controlled synthesis of carbon nanotubes and the incorporation of multifunctionality are essential for the development of this ever-expanding field, ultimately leading to the effective control of the pathways of chemical reactions through the rational design of multi-functional carbon nanoreactors.

  4. Confined Tube Crimp Using Portable Hand Tools

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, Joseph James [Los Alamos National Laboratory; Pereyra, R. A. [LANL Retired; Archuleta, Jeffrey Christopher [Los Alamos National Laboratory; Martinez, Isaac P. [Los Alamos National Laboratory; Nelson, A. M. [MST-16 Summer Student (2007); Allen, Ronald Scott [Los Alamos National Laboratory; Page, R. L. [LANL Retired; Freer, Jerry Eugene [Los Alamos National Laboratory; Dozhier, Nathan Gus [Los Alamos National Laboratory


    The Lawrence Radiation Laboratory developed handheld tools that crimp a 1/16 inch OD tube, forming a leak tight seal1 (see Figure 1). The leak tight seal forms by confining the 1/16 inch OD tubing inside a die while applying crimp pressure. Under confined pressure, the tube walls weld at the crimp. The purpose of this study was to determine conditions for fabricating a leak tight tube weld. The equipment was used on a trial-and-error basis, changing the conditions after each attempt until successful welds were fabricated. To better confine the tube, the die faces were polished. Polishing removed a few thousandths of an inch from the die face, resulting in a tighter grip on the tubing wall. Using detergent in an ultrasonic bath, the tubing was cleaned. Also, the time under crimp pressure was increased to 30 seconds. With these modifications, acceptable cold welds were fabricated. After setting the conditions for an acceptable cold weld, the tube was TIG welded across the crimped face.


    Directory of Open Access Journals (Sweden)

    J. M. Maluf


    Full Text Available In order to evaluate the performance and carcass characteristics of cattle cross breeds ½ Aberdeen Angus x ½Nelore and Nelore confined submitted to immunocastration 218 male animals were used, feedlot, averaging 342 kg, divided into three experimental groups, T1: 117 steers ½ Angus x ½ Nelore no castrated (ANC, T2: 51 Nelore steers uncastrated (NNC and T3: 50 Nellore steers immunocastrated (NIC. The experiment lasted 144 days of confinement. The selection of animals for group formation was according to the individual weight, breed, sex condition and age. For immunocastration it wasused Bopriva® vaccine. The rating was finished according to the parameter used by the meatpacking industry ranging from 1 to 5. The experimental design was completely randomized in three groups. For the analyzes the variables studied statistics were submitted to analysis of variance (ANOVA and Tukey test both at the 5% level of significance. The results showed differences (p <0.01 at various features of productive performance and carcass between treatments. For slaughter weight, the ANC animals were higher (with 582.1 kg to Nelore, regardless of sexual condition, and the NNC were in turn heavier than the NIC, 527.4 and 503.7 respectively. Finally, it observed that the use of immunocastration in Nellore animals provided a decrease in productive performance of confined animals, but provided better finish carcass similar to crossbred (ANC.

  6. Water nanodroplets confined in zeolite pores. (United States)

    Coudert, François-Xavier; Cailliez, Fabien; Vuilleumier, Rodolphe; Fuchs, Alain H; Boutin, Anne


    We provide a comprehensive depiction of the behaviour of a nanodroplet of approximately equal to 20 water molecules confined in the pores of a series of 3D-connected isostructural zeolites with varying acidity, by means of molecular simulations. Both grand canonical Monte Carlo simulations using classical interatomic forcefields and first-principles Car-Parrinello molecular dynamics were used in order to characterise the behaviour of confined water by computing a range of properties, from thermodynamic quantities to electronic properties such as dipole moment, including structural and dynamical information. From the thermodynamic point of view, we have identified the all-silica zeolite as hydrophobic, and the cationic zeolites as hydrophilic; the condensation transition in the first case was demonstrated to be of first order. Furthermore, in-depth analysis of the dynamical and electronic properties of water showed that water in the hydrophobic zeolite behaves as a nanodroplet trying to close its hydrogen-bond network onto itself, with a few short-lived dangling OH groups, while water in hydrophilic zeolites "opens up" to form weak hydrogen bonds with the zeolite oxygen atoms. Finally, the dipole moment of confined water is studied and the contributions of water self-polarisation and the zeolite electric field are discussed.

  7. Dynamics of Hyperbranched Polymers under Confinement (United States)

    Androulaki, Krystallenia; Chrissopoulou, Kiriaki; Anastasiadis, Spiros H.; Prevosto, Daniele; Labardi, Massimiliano


    The effect of severe confinement on the dynamics of three different generations of hyperbranched polyesters (Boltorns) is investigated by Dielectric Spectroscopy. The polymers are intercalated within the galleries of natural Na+-MMT, thus, forming 1nm polymer films confined between solid walls. The Tg's of the polymers determined by DSC show a clear dependence on the generation whereas the transition is completely suppressed when all the polymer chains are intercalated. The dynamic investigation of the bulk polymers reveals two sub-Tg processes, with similar behavior for the three polymers with the segmental relaxation observed above the Tg of each. For the nanocomposites, where all polymers are severely confined, the dynamics show significant differences compared to that of the bulk polymers. The sub-Tg processes are similar for the three generations but significantly faster and with weaker temperature dependence than those in the bulk. The segmental process appears at temperatures below the bulk polymer Tg, it exhibits an Arrhenius temperature dependence and shows differences for the three generations. A slow process that appears at higher temperatures is due to interfacial polarization. Co-financed by the EU and Greek funds through the Operational Program ``Education and Lifelong Learning'' of the NSRF-Research Funding Program: THALES-Investing in knowledge society through the Eur. Social Fund (MIS 377278) and COST Action MP0902-COINAPO.

  8. Quantum Confinement at Polar Oxide Interfaces (United States)

    Gariglio, Stefano; Li, Danfeng; Wu, Zhenping; Liu, Wei; Fete, Alexandre; Boselli, Margherita; Lemal, Sebastien; Bristowe, Nicholas; Ghosez, Philippe; Gabay, Marc; Triscone, Jean-Marc

    The discovery of a two-dimensional electron liquid (2DEL), confined at the interface between the two band insulators LaAlO3 (LAO) and SrTiO3 (STO) has generated tremendous research interest. The 2DEL confinement lifts the degeneracy of Ti t2 g orbitals and promotes exotic physical properties. A previous study has demonstrated that a 2DEL is also observed when LAO is alloyed with STO (La,Al)1-x(Sr,Ti)xO3 (LASTO: x). The threshold thickness required for the onset of conductivity scales with x. We present here a study of superconductivity at the (LASTO:0.5)/STO interface. The thickness of the 2DEL, measured using perpendicular and parallel critical fields, is larger than the one at the LAO/STO interface. This change is due to a modification on the confining potential linked to a reduced charge transfer that is scaling as 1 / x . This scenario is also confirmed by a self-consistent Poisson-Schrödinger model and ab initio calculations. These compelling evidences support an intrinsic origin to the formation of the 2DEL in the LAO/STO system.

  9. -Net Approach to Sensor -Coverage

    Directory of Open Access Journals (Sweden)

    Fusco Giordano


    Full Text Available Wireless sensors rely on battery power, and in many applications it is difficult or prohibitive to replace them. Hence, in order to prolongate the system's lifetime, some sensors can be kept inactive while others perform all the tasks. In this paper, we study the -coverage problem of activating the minimum number of sensors to ensure that every point in the area is covered by at least sensors. This ensures higher fault tolerance, robustness, and improves many operations, among which position detection and intrusion detection. The -coverage problem is trivially NP-complete, and hence we can only provide approximation algorithms. In this paper, we present an algorithm based on an extension of the classical -net technique. This method gives an -approximation, where is the number of sensors in an optimal solution. We do not make any particular assumption on the shape of the areas covered by each sensor, besides that they must be closed, connected, and without holes.

  10. Confined Turbulent Swirling Recirculating Flow Predictions. Ph.D. Thesis (United States)

    Abujelala, M. T.


    Turbulent swirling flow, the STARPIC computer code, turbulence modeling of turbulent flows, the k-xi turbulence model and extensions, turbulence parameters deduction from swirling confined flow measurements, extension of the k-xi to confined swirling recirculating flows, and general predictions for confined turbulent swirling flow are discussed.

  11. NETS - Danish participation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Alsen, S. (Grontmij - Carl Bro, Glostrup (Denmark)); Theel, C. (Baltic Sea Solutions, Holeby (Denmark))


    Within the NICe-funded project 'Nordic Environmental Technology Solutions (NETS)' a new type of networking at the Nordic level was organized in order to jointly exploit the rapidly growing market potential in the environmental technology sector. The project aimed at increased and professionalized commercialization of Nordic Cleantech in energy and water business segments through 1) closer cooperation and joint marketing activities, 2) a website, 3) cleantech product information via brochures and publications 4) and participating in relevant trade fairs and other industry events. Facilitating business-to-business activities was another core task for the NETS project partners from Norway, Sweden, Finland and Denmark with the aim to encourage total solutions for combined Cleantech system offers. The project has achieved to establish a Cleantech register of 600 Nordic Cleantech companies, a network of 86 member enterprises, produced several publications and brochures for direct technology promotion and a website for direct access to company profiles and contact data. The project partners have attended 14 relevant international Cleantech trade fairs and conferences and facilitated business-to-business contacts added by capacity building offers through two company workshops. The future challenge for the project partners and Nordic Cleantech will be to coordinate the numerous efforts within the Nordic countries in order to reach concerted action and binding of member companies for reliable services, an improved visibility and knowledge exchange. With Cleantech's growing market influence and public awareness, the need to develop total solutions is increasing likewise. Marketing efforts should be encouraged cross-sectional and cross-border among the various levels of involved actors from both the public and the private sector. (au)

  12. Fault gouge rheology under confined, high-velocity conditions (United States)

    Reches, Z.; Madden, A. S.; Chen, X.


    We recently developed the experimental capability to investigate the shear properties of fine-grain gouge under confined conditions and high-velocity. The experimental system includes a rotary apparatus that can apply large displacements of tens of meters, slip velocity of 0.001- 2.0 m/s, and normal stress of 35 MPa (Reches and Lockner, 2010). The key new component is a Confined ROtary Cell (CROC) that can shear a gouge layer either dry or under pore-pressure. The pore pressure is controlled by two syringe pumps. CROC includes a ring-shape gouge chamber of 62.5 mm inner diameter, 81.25 mm outer diameter, and up to 3 mm thick gouge sample. The lower, rotating part of CROC contains the sample chamber, and the upper, stationary part includes the loading, hollow cylinder and setting for temperature, and dilation measurements, and pore-pressure control. Each side of the gouge chamber has two pairs of industrial, spring-energized, self-lubricating, teflon-graphite seals, built for particle media and can work at temperature up to 250 ded C. The space between each of the two sets of seals is pressurized by nitrogen. This design generates 'zero-differential pressure' on the inner seal (which is in contact with the gouge powder), and prevents gouge leaks. For the preliminary dry experiments, we used ~2.0 mm thick layers of room-dry kaolinite powder. Total displacements were on the order of meters and normal stress up to 4 MPa. The initial shear was accommodated by multiple internal slip surfaces within the kaolinite layer accommodated as oriented Riedel shear structures. Later, the shear was localized within a thin, plate-parallel Y-surface. The kaolinite layer was compacted at a quasi-asymptotic rate, and displayed a steady-state friction coefficient of ~ 0.5 with no clear dependence on slip velocity up to 0.15 m/s. Further experiments with loose quartz sand (grain size ~ 125 micron) included both dry runs and pore-pressure (distilled water) controlled runs. The sand was

  13. Psychological and behavioral changes during confinement in a 520-day simulated interplanetary mission to mars.

    Directory of Open Access Journals (Sweden)

    Mathias Basner

    Full Text Available Behavioral health risks are among the most serious and difficult to mitigate risks of confinement in space craft during long-duration space exploration missions. We report on behavioral and psychological reactions of a multinational crew of 6 healthy males confined in a 550 m(3 chamber for 520 days during the first Earth-based, high-fidelity simulated mission to Mars. Rest-activity of crewmembers was objectively measured throughout the mission with wrist-worn actigraphs. Once weekly throughout the mission crewmembers completed the Beck Depression Inventory-II (BDI-II, Profile of Moods State short form (POMS, conflict questionnaire, the Psychomotor Vigilance Test (PVT-B, and series of visual analogue scales on stress and fatigue. We observed substantial inter-individual differences in the behavioral responses of crewmembers to the prolonged mission confinement and isolation. The crewmember with the highest average POMS total mood disturbance score throughout the mission also reported symptoms of depression in 93% of mission weeks, which reached mild-to-moderate levels in >10% of mission weeks. Conflicts with mission control were reported five times more often than conflicts among crewmembers. Two crewmembers who had the highest ratings of stress and physical exhaustion accounted for 85% of the perceived conflicts. One of them developed a persistent sleep onset insomnia with ratings of poor sleep quality, which resulted in chronic partial sleep deprivation, elevated ratings of daytime tiredness, and frequent deficits in behavioral alertness. Sleep-wake timing was altered in two other crewmembers, beginning in the first few months of the mission and persisting throughout. Two crewmembers showed neither behavioral disturbances nor reports of psychological distress during the 17-month period of mission confinement. These results highlight the importance of identifying behavioral, psychological, and biological markers of characteristics that

  14. Application and Theory of Petri Nets

    DEFF Research Database (Denmark)

    This volume contains the proceedings of the 13th International Conference onApplication and Theory of Petri Nets, held in Sheffield, England, in June 1992. The aim of the Petri net conferences is to create a forum for discussing progress in the application and theory of Petri nets. Typically....... Balbo and W. Reisig, 18 submitted papers, and seven project papers. The submitted papers and project presentations were selectedby the programme committee and a panel of referees from a large number of submissions....

  15. Are You Neutral About Net Neutrality (United States)


    Information Resources Management College National Defense University Are You Neutral About Net Neutrality ? A presentation for Systems & uses Verizon FiOS for phone, TV, and internet service 3 Agenda Net Neutrality —Through 2 Lenses Who Are the Players & What Are They Saying...Medical Treatment Mini-Case Studies Updates Closing Thoughts 4 Working Definitions of Net Neutrality "Network Neutrality" is the concept that

  16. Texture Based Image Analysis With Neural Nets (United States)

    Ilovici, Irina S.; Ong, Hoo-Tee; Ostrander, Kim E.


    In this paper, we combine direct image statistics and spatial frequency domain techniques with a neural net model to analyze texture based images. The resultant optimal texture features obtained from the direct and transformed image form the exemplar pattern of the neural net. The proposed approach introduces an automated texture analysis applied to metallography for determining the cooling rate and mechanical working of the materials. The results suggest that the proposed method enhances the practical applications of neural nets and texture extraction features.

  17. Factors associated with mosquito net use by individuals in households owning nets in Ethiopia

    Directory of Open Access Journals (Sweden)

    Graves Patricia M


    Full Text Available Abstract Background Ownership of insecticidal mosquito nets has dramatically increased in Ethiopia since 2006, but the proportion of persons with access to such nets who use them has declined. It is important to understand individual level net use factors in the context of the home to modify programmes so as to maximize net use. Methods Generalized linear latent and mixed models (GLLAMM were used to investigate net use using individual level data from people living in net-owning households from two surveys in Ethiopia: baseline 2006 included 12,678 individuals from 2,468 households and a sub-sample of the Malaria Indicator Survey (MIS in 2007 included 14,663 individuals from 3,353 households. Individual factors (age, sex, pregnancy; net factors (condition, age, net density; household factors (number of rooms [2006] or sleeping spaces [2007], IRS, women's knowledge and school attendance [2007 only], wealth, altitude; and cluster level factors (rural or urban were investigated in univariate and multi-variable models for each survey. Results In 2006, increased net use was associated with: age 25-49 years (adjusted (a OR = 1.4, 95% confidence interval (CI 1.2-1.7 compared to children U5; female gender (aOR = 1.4; 95% CI 1.2-1.5; fewer nets with holes (Ptrend = 0.002; and increasing net density (Ptrend [all nets in HH good] = 1.6; 95% CI 1.2-2.1; increasing net density (Ptrend [per additional space] = 0.6, 95% CI 0.5-0.7; more old nets (aOR [all nets in HH older than 12 months] = 0.5; 95% CI 0.3-0.7; and increasing household altitude (Ptrend Conclusion In both surveys, net use was more likely by women, if nets had fewer holes and were at higher net per person density within households. School-age children and young adults were much less likely to use a net. Increasing availability of nets within households (i.e. increasing net density, and improving net condition while focusing on education and promotion of net use, especially in school-age children

  18. Pro Agile NET Development with Scrum

    CERN Document Server

    Blankenship, Jerrel; Millett, Scott


    Pro Agile .NET Development with SCRUM guides you through a real-world ASP.NET project and shows how agile methodology is put into practice. There is plenty of literature on the theory behind agile methodologies, but no book on the market takes the concepts of agile practices and applies these in a practical manner to an end-to-end ASP.NET project, especially the estimating, requirements and management aspects of a project. Pro Agile .NET Development with SCRUM takes you through the initial stages of a project - gathering requirements and setting up an environment - through to the development a

  19. Pro ASP.NET MVC 4

    CERN Document Server

    Freeman, Adam


    The ASP.NET MVC 4 Framework is the latest evolution of Microsoft's ASP.NET web platform. It provides a high-productivity programming model that promotes cleaner code architecture, test-driven development, and powerful extensibility, combined with all the benefits of ASP.NET. ASP.NET MVC 4 contains a number of significant advances over previous versions. New mobile and desktop templates (employing adaptive rendering) are included together with support for jQuery Mobile for the first time. New display modes allow your application to select views based on the browser that's making the request whi

  20. Professional Visual Basic 2010 and .NET 4

    CERN Document Server

    Sheldon, Bill; Sharkey, Kent


    Intermediate and advanced coverage of Visual Basic 2010 and .NET 4 for professional developers. If you've already covered the basics and want to dive deep into VB and .NET topics that professional programmers use most, this is your book. You'll find a quick review of introductory topics-always helpful-before the author team of experts moves you quickly into such topics as data access with ADO.NET, Language Integrated Query (LINQ), security, ASP.NET web programming with Visual Basic, Windows workflow, threading, and more. You'll explore all the new features of Visual Basic 2010 as well as all t

  1. NASA Net Zero Energy Buildings Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Pless, S.; Scheib, J.; Torcellini, P.; Hendron, B.; Slovensky, M.


    In preparation for the time-phased net zero energy requirement for new federal buildings starting in 2020, set forth in Executive Order 13514, NASA requested that the National Renewable Energy Laboratory (NREL) to develop a roadmap for NASA's compliance. NASA detailed a Statement of Work that requested information on strategic, organizational, and tactical aspects of net zero energy buildings. In response, this document presents a high-level approach to net zero energy planning, design, construction, and operations, based on NREL's first-hand experience procuring net zero energy construction, and based on NREL and other industry research on net zero energy feasibility. The strategic approach to net zero energy starts with an interpretation of the executive order language relating to net zero energy. Specifically, this roadmap defines a net zero energy acquisition process as one that sets an aggressive energy use intensity goal for the building in project planning, meets the reduced demand goal through energy efficiency strategies and technologies, then adds renewable energy in a prioritized manner, using building-associated, emission- free sources first, to offset the annual energy use required at the building; the net zero energy process extends through the life of the building, requiring a balance of energy use and production in each calendar year.

  2. Towards a Standard for Modular Petri Nets

    DEFF Research Database (Denmark)

    Kindler, Ekkart; Petrucci, Laure


    When designing complex systems, mechanisms for structuring, composing, and reusing system components are crucial. Today, there are many approaches for equipping Petri nets with such mechanisms. In the context of defining a standard interchange format for Petri nets, modular PNML was defined....... Moreover, we present and discuss some more advanced features of modular Petri nets that could be included in the standard. This way, we provide a formal foundation and a basis for a discussion of features to be included in the upcoming standard of a module concept for Petri nets in general and for high...

  3. Energy confinement scaling from the international stellarator database

    Energy Technology Data Exchange (ETDEWEB)

    Stroth, U. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Murakami, M.; Dory, R.A.; Yamada, H.; Okamura, S.; Sano, F.; Obiki, T.


    An international stellarator database on global energy confinement is presented comprising data from the ATF, CHS and Heliotron E heliotron/torsatrons and the W7-A and W7-AS shearless stellarators. Regression expressions for the energy confinement time are given for the individual devices and the combined dataset. A comparison with tokamak L mode confinement is discussed on the basis of various scaling expressions. In order to make this database available to interested colleagues, the structure of the database and the parameter list are explained in detail. More recent confinement results incorporating data from enhanced confinement regimes such as H mode are reported elsewhere. (author).

  4. Generalized inflation and confinement phase transitions in the early universe. (United States)

    Patzelt, H.


    Giving up the restriction ɛ/p = const, the author shows that equations of state with ɛ-3p = Δ > 0 will be driven to the inflationary solution with ɛ = -p after sufficiently long times. Subsequently, he shows that confinement transitions may provide such an equation of state due to a change of degrees of freedom. Depending on the energy scale of the confinement transition inflation may occur during confinement. Numerical results for quark and subquark confinement are given. For QCD-confinement the transition time is too short, compared to the energy density, for a significant deviation of the scale factor to occur.

  5. Generalized inflation and confinement phase transitions in the early universe

    Energy Technology Data Exchange (ETDEWEB)

    Patzelt, H. (Muenchen Univ. (Germany, F.R.). Sektion Physik)


    Giving up the restriction {epsilon}/p=const, we show that equations of state with {epsilon}-3p={Delta}>0 will be driven to the inflationary solution with {epsilon}=-p after sufficiently long times. Subsequently, we show that confinement transitions may provide such an equation of state due to a change of degrees of freedom. Depending on the energy scale of the confinement transition inflation may occur during confinement. Numerical results for quark and subquark confinement are given. For QCD-confinement the transition time is too short, compared to the energy density, for a significant deviation of the scale factor to occur. (orig.).

  6. Experiments and simulation of a net closing mechanism for tether-net capture of space debris (United States)

    Sharf, Inna; Thomsen, Benjamin; Botta, Eleonora M.; Misra, Arun K.


    This research addresses the design and testing of a debris containment system for use in a tether-net approach to space debris removal. The tether-net active debris removal involves the ejection of a net from a spacecraft by applying impulses to masses on the net, subsequent expansion of the net, the envelopment and capture of the debris target, and the de-orbiting of the debris via a tether to the chaser spacecraft. To ensure a debris removal mission's success, it is important that the debris be successfully captured and then, secured within the net. To this end, we present a concept for a net closing mechanism, which we believe will permit consistently successful debris capture via a simple and unobtrusive design. This net closing system functions by extending the main tether connecting the chaser spacecraft and the net vertex to the perimeter and around the perimeter of the net, allowing the tether to actuate closure of the net in a manner similar to a cinch cord. A particular embodiment of the design in a laboratory test-bed is described: the test-bed itself is comprised of a scaled-down tether-net, a supporting frame and a mock-up debris. Experiments conducted with the facility demonstrate the practicality of the net closing system. A model of the net closure concept has been integrated into the previously developed dynamics simulator of the chaser/tether-net/debris system. Simulations under tether tensioning conditions demonstrate the effectiveness of the closure concept for debris containment, in the gravity-free environment of space, for a realistic debris target. The on-ground experimental test-bed is also used to showcase its utility for validating the dynamics simulation of the net deployment, and a full-scale automated setup would make possible a range of validation studies of other aspects of a tether-net debris capture mission.

  7. Improved energy confinement with nonlinear isotope effects in magnetically confined plasmas

    CERN Document Server

    Garcia, J; Jenko, F


    The efficient production of electricity from nuclear fusion in magnetically confined plasmas relies on a good confinement of the thermal energy. For more than thirty years, the observation that such confinement depends on the mass of the plasma isotope and its interaction with apparently unrelated plasma conditions has remained largely unexplained and it has become one of the main unsolved issues. By means of numerical studies based on the gyrokinetic theory, we quantitatively show how the plasma microturbulence depends on the isotope mass through nonlinear multiscale microturbulence effects involving the interplay between zonal flows, electromagnetic effects and the torque applied. This finding has crucial consequences for the design of future reactors since, in spite of the fact that they will be composed by multiple ion species, their extrapolation from present day experiments heavily relies on the knowledge obtained from a long experimental tradition based in single isotope plasmas.

  8. Confinement in a planar waveguide with porous silicon omnidirectional mirrors as confining walls

    Energy Technology Data Exchange (ETDEWEB)

    Xifre-Perez, E. [Departament d' Enginyeria Electronica, Electrica i Automatica, ETSE, Campus Sescelades, Universitat Rovira i Virgili, Avda. Paisos Catalans 26, 43007 Tarragona (Spain); Marsal, L.F. [Departament d' Enginyeria Electronica, Electrica i Automatica, ETSE, Campus Sescelades, Universitat Rovira i Virgili, Avda. Paisos Catalans 26, 43007 Tarragona (Spain)]. E-mail:; Ferre-Borrull, J. [Departament d' Enginyeria Electronica, Electrica i Automatica, ETSE, Campus Sescelades, Universitat Rovira i Virgili, Avda. Paisos Catalans 26, 43007 Tarragona (Spain); Pallares, J. [Departament d' Enginyeria Electronica, Electrica i Automatica, ETSE, Campus Sescelades, Universitat Rovira i Virgili, Avda. Paisos Catalans 26, 43007 Tarragona (Spain)


    We present the design and study of waveguide structures based on porous silicon where the light confinement is not due to the usual total reflection effect but to the use of photonic crystals (PCs) as confining walls. These PC are omnidirectional mirrors (OMs), consisting of the periodic repetition of two porous silicon layers with different refractive indices and thicknesses. They reflect the radiation for all angles of incidence within a frequency range called the omnidirectional band gap (OBG). We have followed the PC formalism to investigate the properties of the OM as a multimode waveguide: the number of modes within the band gap, their field spatial distribution and their confinement as a function of the frequency and the core thickness.

  9. Spherical microwave confinement and ball lightning (United States)

    Robinson, William Richard

    This dissertation presents the results of research done on unconventional energy technologies from 1995 to 2009. The present civilization depends on an infrastructure that was constructed and is maintained almost entirely using concentrated fuels and ores, both of which will run out. Diffuse renewable energy sources rely on this same infrastructure, and hence face the same limitations. I first examined sonoluminescence directed toward fusion, but demonstrated theoretically that this is impossible. I next studied Low Energy Nuclear Reactions and developed methods for improving results, although these have not been implemented. In 2000, I began Spherical Microwave Confinement (SMC), which confines and heats plasma with microwaves in a spherical chamber. The reactor was designed and built to provide the data needed to investigate the possibility of achieving fusion conditions with microwave confinement. A second objective was to attempt to create ball lightning (BL). The reactor featured 20 magnetrons, which were driven by a capacitor bank and operated in a 0.2 s pulse mode at 2.45 GHz. These provided 20 kW to an icosahedral array of 20 antennas. Video of plasmas led to a redesign of the antennas to provide better coupling of the microwaves to the plasma. A second improvement was a grid at the base of the antennas, which provided corona electrons and an electric field to aid quick formation of plasmas. Although fusion conditions were never achieved and ball lightning not observed, experience gained from operating this basic, affordable system has been incorporated in a more sophisticated reactor design intended for future research. This would use magnets that were originally planned. The cusp geometry of the magnetic fields is suitable for electron cyclotron resonance in the same type of closed surface that in existing reactors has generated high-temperature plasmas. Should ball lightning be created, it could be a practical power source with nearly ideal

  10. Statistical Contact Model for Confined Molecules (United States)

    Santamaria, Ruben; de la Paz, Antonio Alvarez; Roskop, Luke; Adamowicz, Ludwik


    A theory that describes in a realistic form a system of atoms under the effects of temperature and confinement is presented. The theory departs from a Lagrangian of the Zwanzig type and contains the main ingredients for describing a system of atoms immersed in a heat bath that is also formed by atoms. The equations of motion are derived according to Lagrangian mechanics. The application of statistical mechanics to describe the bulk effects greatly reduces the complexity of the equations. The resultant equations of motion are of the Langevin type with the viscosity and the temperature of the heat reservoir able to influence the trajectories of the particles. The pressure effects are introduced mechanically by using a container with an atomic structure immersed in the heat bath. The relevant variables that determine the equation of state are included in the formulation. The theory is illustrated by the derivation of the equation of state for a system with 76 atoms confined inside of a 180-atom fullerene-like cage that is immersed in fluid forming the heat bath at a temperature of 350 K and with the friction coefficient of 3.0 {ps}^{-1}. The atoms are of the type believed to form the cores of the Uranus and Neptune planets. The dynamic and the static pressures of the confined system are varied in the 3-5 KBar and 2-30 MBar ranges, respectively. The formulation can be equally used to analyze chemical reactions under specific conditions of pressure and temperature, determine the structure of clusters with their corresponding equation of state, the conditions for hydrogen storage, etc. The theory is consistent with the principles of thermodynamics and it is intrinsically ergodic, of general use, and the first of this kind.

  11. HANPP Collection: Human Appropriation of Net Primary Productivity as a Percentage of Net Primary Productivity (United States)

    National Aeronautics and Space Administration — The Human Appropriation of Net Primary Productivity (HANPP) as a Percentage of Net Primary Product (NPP) portion of the HANPP Collection represents a map identifying...

  12. Electrical charging effects on the sliding friction of a model nano-confined ionic liquid

    Energy Technology Data Exchange (ETDEWEB)

    Capozza, R.; Vanossi, A. [International School for Advanced Studies (SISSA), Via Bonomea 265, 34136 Trieste (Italy); CNR-IOM Democritos National Simulation Center, Via Bonomea 265, 34136 Trieste (Italy); Benassi, A. [CNR-IOM Democritos National Simulation Center, Via Bonomea 265, 34136 Trieste (Italy); Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden (Germany); Tosatti, E. [International School for Advanced Studies (SISSA), Via Bonomea 265, 34136 Trieste (Italy); CNR-IOM Democritos National Simulation Center, Via Bonomea 265, 34136 Trieste (Italy); International Centre for Theoretical Physics (ICTP), Strada Costiera 11, 34014 Trieste (Italy)


    Recent measurements suggest the possibility to exploit ionic liquids (ILs) as smart lubricants for nano-contacts, tuning their tribological and rheological properties by charging the sliding interfaces. Following our earlier theoretical study of charging effects on nanoscale confinement and squeezout of a model IL, we present here molecular dynamics simulations of the frictional and lubrication properties of that model under charging conditions. First, we describe the case when two equally charged plates slide while being held together to a confinement distance of a few molecular layers. The shear sliding stress is found to rise strongly and discontinuously as the number of IL layers decreases stepwise. However, the shear stress shows, within each given number of layers, only a weak dependence upon the precise value of the normal load, a result in agreement with data extracted from recent experiments. We subsequently describe the case of opposite charging of the sliding plates and follow the shear stress when the charging is slowly and adiabatically reversed in the course of time, under fixed load. Despite the fixed load, the number and structure of the confined IL layers change with changing charge, and that in turn drives strong friction variations. The latter involves first of all charging-induced freezing of the IL film, followed by a discharging-induced melting, both made possible by the nanoscale confinement. Another mechanism for charging-induced frictional changes is a shift of the plane of maximum shear from mid-film to the plate-film interface, and vice versa. While these occurrences and results invariably depend upon the parameters of the model IL and upon its specific interaction with the plates, the present study helps identifying a variety of possible behavior, obtained under very simple assumptions, while connecting it to an underlying equilibrium thermodynamics picture.


    Directory of Open Access Journals (Sweden)

    Xiang Zeng


    Full Text Available The strain rate sensitivity of concrete material was discovered approximately one hundred years ago, and it has a marked effect on the behaviour of concrete members subjected to dynamic loadings such as strong earthquake and impact loading. Because of the great importance of the confined reinforced concrete (RC columns in RC structures, the dynamic behaviour of the columns induced by the strain rate effect has been studied, but only few experiments and analyses have been conducted. To investigate the behaviour of overlapping hoop-confined square reinforced normal-strength concrete columns, considering the strain rate effect at a strain rate of 10-5/sec to 10-1/sec induced by earthquake excitation, an explicit dynamic finite element analysis (FEA model was developed in ABAQUS to predict the behaviour of confined RC columns subjected to the rapid concentric loading. A locally modified stress-strain relation of confined concrete with the strain rate sensitivity of the concrete material and the confining effect of overlapping hoops were proposed to complete the simulation of the dynamic behaviour of concrete with the concrete plastic-constitutive model in ABAQUS. The finite element predictions are consistent with the existing test results. Based on the FEA model, a parametric investigation was conducted to capture more information about the behaviour of confined RC columns under varying loading rates.

  14. Dynamics of Liquids Confined in Porous Materials

    DEFF Research Database (Denmark)

    Berg, Marcella Cabrera

    to the understanding of the nature of the hydration in the GIC and can be applied towards the development and improvement of dental restorative materials. Furthermore, two manuscripts regarding water and protein dynamics in confinement probed by quasi-elastic neutron scattering are also included in the thesis, Paper 3...... and Paper 4. In Paper 3 we investigated why two chalk samples display vastly different water uptake, despite the fact that they are known to have similar pore volumes. In Paper 4 we investigated the dynamics of encapsulated Hepatitis B surface antigen in mesoporous silica SBA-15. My knowledge of liquids...

  15. Confining quark condensate model of the nucleon.

    Energy Technology Data Exchange (ETDEWEB)

    Frank, Michael; Tandy, Peter


    We obtain a mean-field solution for the nucleon as a quark-meson soliton obtained from the action of the global color-symmetry model of QCD. All dynamics is generated from an effective interaction of quark currents. At the quark-meson level there are two novel features: (1) absolute confinement is produced from the space-time structure of the dynamical self-energy in the vacuum quark propagator; and (2) the related scalar meson field is an extended q-barq composite that couples nonlocally to quarks. The influence of these features upon the nucleon mass contributions and other nucleon properties is presented.

  16. The Gribov theory of quark confinement

    CERN Document Server


    V N Gribov, one of the founders of modern particle physics, shaped our understanding of QCD as the microscopic dynamics of hadrons. This volume collects his papers on quark confinement, showing the road he followed to arrive at the theory and formulating the theory itself. It begins with papers providing a beautiful physical explanation of asymptotic freedom based on the phenomenon of antiscreening and demonstrating the inconsistency of the standard perturbative treatment of the gluon fields (Gribov copies, Gribov horizon). It continues with papers presenting the Gribov theory according to whi

  17. Isolation and confinement - Considerations for colonization (United States)

    Akins, F. R.


    This paper discusses three types of isolation (sensory/perceptual, temporal, and social) that could adversely affect mankind in space. The literature dealing with laboratory and field experiments relevant to these areas is summarized and suggestions are given for dealing with these problems within the space colony community. Also, consideration is given to the potential effects of physical confinement and the need for usable space. Finally, a modification of Maslow's hierarchy of needs is proposed as a theoretical framework to understand and investigate mankind's psychological needs in space.

  18. Honeycomb optical lattices with harmonic confinement

    DEFF Research Database (Denmark)

    Jacobsen, Jens Kusk Block; Nygaard, Nicolai


    We consider the fate of the Dirac points in the spectrum of a honeycomb optical lattice in the presence of a harmonic confining potential. By numerically solving the tight binding model, we calculate the density of states and find that the energy dependence can be understood from analytical...... arguments. In addition, we show that the density of states of the harmonically trapped lattice system can be understood by application of a local density approximation based on the density of states in the homogeneous lattice. The Dirac points are found to survive locally in the trap as evidenced...

  19. Diamond Ablators for Inertial Confinement Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Biener, J; Mirkarimi, P B; Tringe, J W; Baker, S L; Wang, Y M; Kucheyev, S O; Teslich, N E; Wu, K J; Hamza, A V; Wild, C; Woerner, E; Koidl, P; Bruehne, K; Fecht, H


    Diamond has a unique combination of physical properties for the inertial confinement fusion ablator application, such as appropriate optical properties, high atomic density, high yield strength, and high thermal conductivity. Here, we present a feasible concept to fabricate diamond ablator shells. The fabrication of diamond capsules is a multi-step process, which involves diamond chemical vapor deposition on silicon mandrels followed by polishing, microfabrication of holes, and removing of the silicon mandrel by an etch process. We also discuss the pros and cons of coarse-grained optical quality and nanocrystalline chemical vapor deposition diamond films for the ablator application.

  20. Magnetic confinement of repelling Bloch walls (United States)

    Magyari, E.; Thomas, H.


    In a ferromagnet with orthorhombic magneto-crystalline anisotropy, two repelling 180° domain walls (π kinks) can be pushed together to form a 360° domain wall (2π kink) by applying a magnetic field in the easy direction. We show that such a magnetically confined static 360° plane domain wall with Bloch-like structure, connecting two semi-infinite domains with parallel spin orientation, is linearly stable only below a critical strength Bc of the applied field. At B = Bc it becomes unstable with respect to a mode with spin component along the hard direction.

  1. Price smarter on the Net. (United States)

    Baker, W; Marn, M; Zawada, C


    Companies generally have set prices on the Internet in two ways. Many start-ups have offered untenably low prices in a rush to capture first-mover advantage. Many incumbents have simply charged the same prices on-line as they do off-line. Either way, companies are missing a big opportunity. The fundamental value of the Internet lies not in lowering prices or making them consistent but in optimizing them. After all, if it's easy for customers to compare prices on the Internet, it's also easy for companies to track customers' behavior and adjust prices accordingly. The Net lets companies optimize prices in three ways. First, it lets them set and announce prices with greater precision. Different prices can be tested easily, and customers' responses can be collected instantly. Companies can set the most profitable prices, and they can tap into previously hidden customer demand. Second, because it's so easy to change prices on the Internet, companies can adjust prices in response to even small fluctuations in market conditions, customer demand, or competitors' behavior. Third, companies can use the clickstream data and purchase histories that it collects through the Internet to segment customers quickly. Then it can offer segment-specific prices or promotions immediately. By taking full advantage of the unique possibilities afforded by the Internet to set prices with precision, adapt to changing circumstances quickly, and segment customers accurately, companies can get their pricing right. It's one of the ultimate drivers of e-business success.

  2. Vertical groundwater storage properties and changes in confinement determined using hydraulic head response to atmospheric tides (United States)

    Acworth, R. Ian; Rau, Gabriel C.; Halloran, Landon J. S.; Timms, Wendy A.


    Accurate determination of groundwater state of confinement and compressible storage properties at vertical resolution over depth is notoriously difficult. We use the hydraulic head response to atmospheric tides at 2 cpd frequency as a tracer to quantify barometric efficiency (BE) and specific storage (Ss) over depth. Records of synthesized Earth tides, atmospheric pressure, and hydraulic heads measured in nine piezometers completed at depths between 5 and 55 m into unconsolidated smectitic clay and silt, sand and gravel were examined in the frequency domain. The barometric efficiency increased over depth from ˜0.05 in silty clay to ˜0.15 in sands and gravels. BE for silty clay was confirmed by calculating the loading efficiency as 0.95 using rainfall at the surface. Specific storage was calculated using effective rather than total moisture. The differences in phase between atmospheric pressure and hydraulic heads at 2 cpd were ˜180° below 10 m indicating confined conditions despite the low BE. Heads in the sediment above a fine sand and silt layer at 12 m exhibited a time variable phase difference between 0° and 180° indicating varying confinement. Our results illustrate that the atmospheric tide at 2 cpd is a powerful natural tracer for quantifying groundwater state of confinement and compressible storage properties in layered formations from hydraulic heads and atmospheric pressure records without the need for externally induced hydraulic stress. This approach could significantly improve the development of conceptual hydrogeological model used for groundwater resource development and management.

  3. Magnetic Bion Condensation: A New Mechanism ofConfinement and Mass Gap in Four Dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Unsal, Mithat; /SLAC /Stanford U., Phys. Dept.


    In recent work, we derived the long distance confining dynamics of certain QCD-like gauge theories formulated on small S{sup 1} x R{sup 3} based on symmetries, an index theorem and abelian duality. Here, we give the microscopic derivation. The solution reveals a new mechanism of confinement in QCD(adj) in the regime where we have control over both perturbative and nonperturbative aspects. In particular, consider SU(2) QCD(adj) theory with 1 {le} n{sub f} {le} 4 Majorana fermions, a theory which undergoes gauge symmetry breaking at small S{sup 1}. If the magnetic charge of the BPS monopole is normalized to unity, we show that confinement occurs due to condensation of objects with magnetic charge 2, not 1. Due to index theorems, we know that such an object cannot be a two identical monopole configuration. Its net topological charge must vanish, and hence it must be topologically indistinguishable from the perturbative vacuum. We construct such objects, the magnetically charged, topologically null molecules of a BPS monopole and {bar K}{bar K} antimonopole, which we refer as magnetic bions. An immediate puzzle with this proposal is the apparent Coulomb repulsion between BPS-{bar K}{bar K} pair. An attraction which overcomes the Coulomb repulsion between the two is induced by 2n{sub f} -fermion exchange. Bion condensation is also the mechanism of confinement in N = 1 SYM on the same four-manifold. The SU(N) generalization hints a possible hidden integrability behind nonsupersymmetric QCD of affine Toda type, and allows us to analytically compute the string tensions and thicknesses. We currently do not know the extension to R{sup 4}.

  4. Confinement of Reinforced-Concrete Columns with Non-Code Compliant Confining Reinforcement plus Supplemental Pen-Binder

    Directory of Open Access Journals (Sweden)

    Anang Kristianto


    Full Text Available One of the important requirements for earthquake resistant building related to confinement is the use of seismic hooks in the hoop or confining reinforcement of reinforced-concrete column elements. However, installation of a confining reinforcement with a 135-degree hook is not easy. Therefore, in practice, many construction workers apply a confining reinforcement with a 90-degreehook (non-code compliant. Based on research and records of recent earthquakes in Indonesia, the use of a non-code compliant confining reinforcement for concrete columns produces structures with poor seismic performance. This paper presents a study that introduces an additional element that is expected to improve the effectiveness of concrete columns confined with a non-code compliant confining reinforcement. The additional element, named a pen-binder, is used to keep the non-code compliant confining reinforcement in place. The effectiveness of this element under pure axial concentric loading was investigatedcomprehensively.The specimens tested in this study were 18 concrete columns,with a cross-section of 170 mm x 170 mm and a height of 480 mm. The main test variables were the material type of the pen-binder, the angle of the hook, and the confining reinforcement configuration.The test results indicate that adding pen-binders can effectively improve the strength and ductility of the column specimens confined with a non-code compliant confining reinforcement

  5. 78 FR 72393 - Net Investment Income Tax (United States)


    ... Investment Income Tax; Final and Proposed Rules #0;#0;Federal Register / Vol. 78, No. 231 / Monday, December... Parts 1 and 602 RIN 1545-BK44 Net Investment Income Tax AGENCY: Internal Revenue Service (IRS), Treasury... Investment Income Tax and the computation of Net Investment Income. The regulations affect individuals...

  6. 77 FR 72611 - Net Investment Income Tax (United States)


    ... December 5, 2012 Part V Department of the Treasury Internal Revenue Service 26 CFR Part 1 Net Investment... Investment Income Tax AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice of proposed rulemaking...) the individual's net investment income for such taxable year, or (B) the excess (if any) of (i) the...

  7. Net analyte signal based statistical quality control

    NARCIS (Netherlands)

    Skibsted, E.T.S.; Boelens, H.F.M.; Westerhuis, J.A.; Smilde, A.K.; Broad, N.W.; Rees, D.R.; Witte, D.T.


    Net analyte signal statistical quality control (NAS-SQC) is a new methodology to perform multivariate product quality monitoring based on the net analyte signal approach. The main advantage of NAS-SQC is that the systematic variation in the product due to the analyte (or property) of interest is

  8. Asynchronous stream processing with S-Net

    NARCIS (Netherlands)

    Grelck, C.; Scholz, S.-B.; Shafarenko, A.


    We present the rationale and design of S-Net, a coordination language for asynchronous stream processing. The language achieves a near-complete separation between the application code, written in any conventional programming language, and the coordination/communication code written in S-Net. Our

  9. Using the MVC architecture on . NET platform


    Ježek, David


    This thesis deals with usage of MVC (Model View Controller) technology in web development on ASP.NET platform from Microsoft. Mainly it deals with latest version of framework ASP.NET MVC 3. First part describes MVC architecture and the second describes usage of MVC in certain parts of web application an comparing with PHP.

  10. Analysis of Petri Nets and Transition Systems

    Directory of Open Access Journals (Sweden)

    Eike Best


    Full Text Available This paper describes a stand-alone, no-frills tool supporting the analysis of (labelled place/transition Petri nets and the synthesis of labelled transition systems into Petri nets. It is implemented as a collection of independent, dedicated algorithms which have been designed to operate modularly, portably, extensibly, and efficiently.

  11. 27 CFR 7.27 - Net contents. (United States)


    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Net contents. 7.27 Section 7.27 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF... the net contents are displayed by having the same blown, branded, or burned in the container in...

  12. Petri nets and other models of concurrency

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Sassone, Vladimiro


    This paper retraces, collects, and summarises contributions of the authors - in collaboration with others - on the theme of Petri nets and their categorical relationships to other models of concurrency.......This paper retraces, collects, and summarises contributions of the authors - in collaboration with others - on the theme of Petri nets and their categorical relationships to other models of concurrency....

  13. Delta Semantics Defined By Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kyng, Morten; Madsen, Ole Lehrmann

    This report is identical to an earlier version of May 1978 except that Chapter 5 has been revised. A new paper: "A Petri Net Definition of a System Description Language", DAIMI, April 1979, 20 pages, extends the Petri net model to include a data state representing the program variables. Delta...

  14. Net neutrality and inflation of traffic

    NARCIS (Netherlands)

    Peitz, M.; Schütt, Florian

    Under strict net neutrality Internet service providers (ISPs) are required to carry data without any differentiation and at no cost to the content provider. We provide a simple framework with a monopoly ISP to evaluate the short-run effects of different net neutrality rules. Content differs in its

  15. Net Neutrality and Inflation of Traffic

    NARCIS (Netherlands)

    Peitz, M.; Schütt, F.


    Under strict net neutrality Internet service providers (ISPs) are required to carry data without any differentiation and at no cost to the content provider. We provide a simple framework with a monopoly ISP to evaluate different net neutrality rules. Content differs in its sensitivity to delay.

  16. The Net Neutrality Debate: The Basics (United States)

    Greenfield, Rich


    Rich Greenfield examines the basics of today's net neutrality debate that is likely to be an ongoing issue for society. Greenfield states the problems inherent in the definition of "net neutrality" used by Common Cause: "Network neutrality is the principle that Internet users should be able to access any web content they choose and…

  17. Dynamic response of the thermometric net radiometer (United States)

    J. D. Wilson; W. J. Massman; G. E. Swaters


    We computed the dynamic response of an idealized thermometric net radiometer, when driven by an oscillating net longwave radiation intended roughly to simulate rapid fluctuations of the radiative environment such as might be expected during field use of such devices. The study was motivated by curiosity as to whether non-linearity of the surface boundary conditions...

  18. Teaching and Learning with the Net Generation (United States)

    Barnes, Kassandra; Marateo, Raymond C.; Ferris, S. Pixy


    As the Net Generation places increasingly greater demands on educators, students and teachers must jointly consider innovative ways of teaching and learning. In this, educators are supported by the fact that the Net Generation wants to learn. However, these same educators should not fail to realize that this generation learns differently from…

  19. Verification of Timed-Arc Petri Nets

    DEFF Research Database (Denmark)

    Jacobsen, Lasse; Jacobsen, Morten; Møller, Mikael Harkjær


    Timed-Arc Petri Nets (TAPN) are an extension of the classical P/T nets with continuous time. Tokens in TAPN carry an age and arcs between places and transitions are labelled with time intervals restricting the age of tokens available for transition firing. The TAPN model posses a number...

  20. A Brief Introduction to Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt


    Coloured Petri Nets (CP-nets or CPN) is a graphical oriented language for design, specification, simulation and verification of systems. It is in particular well- suited for systems in which communication, synchronisation and resource sharing are important. Typical examples of application areas a...

  1. Gill net and trammel net selectivity in the northern Aegean Sea, Turkey

    Directory of Open Access Journals (Sweden)

    F. Saadet Karakulak


    Full Text Available Fishing trials were carried out with gill nets and trammel nets in the northern Aegean Sea from March 2004 to February 2005. Four different mesh sizes for the gill nets and the inner panel of trammel nets (16, 18, 20 and 22 mm bar length were used. Selectivity parameters for the five most economically important species, bogue (Boops boops, annular sea bream (Diplodus annularis, striped red mullet (Mullus surmuletus, axillary sea bream (Pagellus acarne and blotched picarel (Spicara maena, caught by the two gears were estimated. The SELECT method was used to estimate the selectivity parameters of a variety of models. Catch composition and catch proportion of several species were different in gill and trammel nets. The length frequency distributions of the species caught by the two gears were significantly different. The bi-modal model selectivity curve gave the best fit for gill net and trammel net data, and there was little difference between the modal lengths of these nets. However, a clear difference was found in catching efficiency. The highest catch rates were obtained with the trammel net. Given that many discard species and small fish are caught by gill nets and trammel nets with a mesh size of 16 mm, it is clear that these nets are not appropriate for fisheries. Consequently, the best mesh size for multispecies fisheries is 18 mm. This mesh size will considerably reduce the numbers of small sized individuals and discard species in the catch.

  2. Discrete, continuous, and hybrid petri nets

    CERN Document Server

    David, René


    Petri nets do not designate a single modeling formalism. In fact, newcomers to the field confess sometimes to be a little puzzled by the diversity of formalisms that are recognized under this "umbrella". Disregarding some extensions to the theoretical modeling capabilities, and looking at the level of abstraction of the formalisms, Condition/Event, Elementary, Place/Transition, Predicate/Transition, Colored, Object Oriented... net systems are frequently encountered in the literature. On the other side, provided with appropriate interpretative extensions, Controled Net Systems, Marking Diagrams (the Petri net generalization of State Diagrams), or the many-many variants in which time can be explicitly incorporated -Time(d), Deterministic, (Generalized) Stochastic, Fuzzy...- are defined. This represents another way to define practical formalisms that can be obtained by the "cro- product" of the two mentioned dimensions. Thus Petri nets constitute a modeling paradigm, understandable in a broad sense as "the total...

  3. Confinement and the supercritical Pomeron in QCD (United States)

    White, Alan R.


    Deep-inelastic diffractive scaling violations have provided fundamental insight into the QCD Pomeron, suggesting a single-gluon inner structure rather than that of a perturbative two-gluon bound state. This paper derives a high-energy, transverse momentum cutoff, confining solution of QCD. The Pomeron, in a first approximation, is a single Reggeized gluon plus a ``wee-parton'' component that compensates for the color and particle properties of the gluon. This solution corresponds to a supercritical phase of Reggeon field theory. Beginning with the multi-Regge behavior of massive quark and gluon amplitudes, Reggeon unitarity is used to derive a Reggeon diagram description of a wide class of multi-Regge amplitudes, including those describing the formation and scattering of bound-state Regge poles. When quark and gluon masses are taken to zero, a logarithmic divergence is produced by helicity-flip Reggeon interactions containing the infrared quark triangle anomaly. With the gauge symmetry partially broken, this divergence selects the bound states and amplitudes of a confining theory. Both the Pomeron and hadrons have an anomalous color-parity wee-parton component. For the Pomeron the wee-parton component determines that it carries negative color charge parity and that the leading singularity is an isolated Regge pole.

  4. Nematode Locomotion in Unconfined and Confined Fluids

    CERN Document Server

    Bilbao, Alejandro; Vanapalli, Siva; Blawzdziewicz, Jerzy


    The millimeter-long soil-dwelling nematode {\\it C. elegans} propels itself by producing undulations that propagate along its body and turns by assuming highly curved shapes. According to our recent study [PLoS ONE \\textbf{7}, e40121 (2012)] all these postures can be accurately described by a piecewise-harmonic-curvature (PHC) model. We combine this curvature-based description with highly accurate hydrodynamic bead models to evaluate the normalized velocity and turning angles for a worm swimming in an unconfined fluid and in a parallel-wall cell. We find that the worm moves twice as fast and navigates more effectively under a strong confinement, due to the large transverse-to-longitudinal resistance-coefficient ratio resulting from the wall-mediated far-field hydrodynamic coupling between body segments. We also note that the optimal swimming gait is similar to the gait observed for nematodes swimming in high-viscosity fluids. Our bead models allow us to determine the effects of confinement and finite thickness...

  5. Coronal Electron Confinement by Double Layers

    CERN Document Server

    Li, T C; Swisdak, M


    In observations of flare-heated electrons in the solar corona, a longstanding problem is the unexplained prolonged lifetime of the electrons compared to their transit time across the source. This suggests confinement. Recent particle-in-cell (PIC) simulations, which explored the transport of pre-accelerated hot electrons through ambient cold plasma, showed that the formation of a highly localized electrostatic potential drop, in the form of a double layer (DL), significantly inhibited the transport of hot electrons (T.C. Li, J.F. Drake, and M. Swisdak, 2012, ApJ, 757, 20). The effectiveness of confinement by a DL is linked to the strength of the DL as defined by its potential drop. In this work, we investigate the scaling of the DL strength with the hot electron temperature by PIC simulations, and find a linear scaling. We demonstrate that the strength is limited by the formation of parallel shocks. Based on this, we analytically determine the maximum DL strength, and find also a linear scaling with the hot e...

  6. Quantum chromodynamics near the confinement limit

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, C.


    These nine lectures deal at an elementary level with the strong interaction between quarks and its implications for the structure of hadrons. Quarkonium systems are studied as a means for measuring the interquark interaction. This is presumably (part of) the answer a solution to QCD must yield, if it is indeed the correct theory of the strong interactions. Some elements of QCD are reviewed, and metaphors for QCD as a confining theory are introduced. The 1/N expansion is summarized as a way of guessing the consequences of QCD for hadron physics. Lattice gauge theory is developed as a means for going beyond perturbation theory in the solution of QCD. The correspondence between statistical mechanics, quantum mechanics, and field theory is made, and simple spin systems are formulated on the lattice. The lattice analog of local gauge invariance is developed, and analytic methods for solving lattice gauge theory are considered. The strong-coupling expansion indicates the existence of a confining phase, and the renormalization group provides a means for recovering the consequences of continuum field theory. Finally, Monte Carlo simulations of lattice theories give evidence for the phase structure of gauge theories, yield an estimate for the string tension characterizing the interquark force, and provide an approximate description of the quarkonium potential in encouraging good agreement with what is known from experiment.

  7. Holographic quenches in a confined phase (United States)

    Myers, Robert C.; Rozali, Moshe; Way, Benson


    We investigate quenches of holographic theories in a confined phase, where the energy injected is insufficient to reach the deconfined phase. In such quenches, thermalization is not associated with gravitational collapse and the formation of a black hole. Nevertheless, we attempt to characterize the late-time state of this scenario. We check a number of notions of thermalization that do not require horizon formation, and find no evidence for thermalization, or even equilibration, for our chosen parameters and initial states. We find that the post-quench behaviour of both local and nonlocal observables exhibit oscillatory behaviour rather than decaying towards equilibrium. We generally find that the response of the nonlocal observables is smoother than that of the local ones. We discuss mechanisms which generate such smoothing, as well as ‘beats’ which appear in the time-dependence of the nonlocal operators for certain classes of quenches. When tuning the quench parameters such that the smoothing is ineffective, we are able to perform ‘entanglement spectroscopy, recovering the spectrum of the confined phase of the theory from the time dependence of the entanglement entropy, as well as other nonlocal observables.

  8. Polymers confined between two parallel plane walls (United States)

    Hsu, Hsiao-Ping; Grassberger, Peter


    Single three-dimensional polymers confined to a slab, i.e., to the region between two parallel plane walls, are studied by Monte Carlo simulations. They are described by N-step walks on a simple cubic lattice confined to the region 1⩽z⩽D. The simulations cover both regions D≪RF and D≫RF (where RF˜Nν is the Flory radius, with ν≈0.587), as well as the cross-over region in between. Chain lengths are up to N=80 000, slab widths up to D=120. In order to test the analysis program and to check for finite size corrections, we actually studied three different models: (a) ordinary random walks (mimicking Θ polymers); (b) self-avoiding walks; and (c) Domb-Joyce walks with the self-repulsion tuned to the point where finite size corrections for free (unrestricted) chains are minimal. For the simulations we employ the pruned-enriched-Rosenbluth method with Markovian anticipation. In addition to the partition sum (which gives us a direct estimate of the forces exerted onto the walls), we measure the density profiles of monomers and of end points transverse to the slab, and the radial extent of the chain parallel to the walls. All scaling laws and some of the universal amplitude ratios are compared to theoretical predictions.

  9. Pro visual C++/CLI and the net 35 platform

    CERN Document Server

    Fraser, Stephen


    Pro Visual C++/CLI and the .NET 3.5 Platform is about writing .NET applications using C++/CLI. While readers are learning the ins and outs of .NET application development, they will also be learning the syntax of C++, both old and new to .NET. Readers will also gain a good understanding of the .NET architecture. This is truly a .NET book applying C++ as its development language not another C++ syntax book that happens to cover .NET.

  10. Experimental Study on the Residual Strength of Coal Under Low Confinement (United States)

    Gao, Fuqiang; Kang, Hongpu


    In underground coal mining, coal rib failure of longwall entries is almost certain due to the relative weakness of coal and the presence of high mining-induced stresses. To maintain the coal's capability of sustaining large loads after failure and substantial deformation, it is crucial to understand its post-peak behavior and subsequently, its residual strength. In this study, triaxial compression tests were performed on a total of 51 coal specimens that were classified into two groups based on the existence of calcite grains. Particular emphasis was given to evaluating the residual strength of the coal specimens. It was found that the presence of calcite grains has significant effect on the brittleness of the coal. Coal specimens containing calcite grains have lower frictional strength than specimens without calcite grains. The tests demonstrated that splitting is completely suppressed when the confinement exceeds 10 % of the coal's unconfined compressive strength. The Coulomb and Hoek-Brown failure criteria satisfactorily fit the coals' the peak strength data over the entire confining stress range. The Hoek-Brown failure criterion satisfactorily fits the residual strength data. The parameter m for residual strength is significantly greater than that of the peak strength for both groups of coal. It was also found that as the confinement increases, the increase in residual strength is greater than the increase in peak strength.

  11. Multiobjective Shape Optimization for Deployment and Adjustment Properties of Cable-Net of Deployable Antenna

    Directory of Open Access Journals (Sweden)

    Guoqiang You


    Full Text Available Based on structural features of cable-net of deployable antenna, a multiobjective shape optimization method is proposed to help to engineer antenna’s cable-net structure that has better deployment and adjustment properties. In this method, the multiobjective optimum mathematical model is built with lower nodes’ locations of cable-net as variables, the average stress ratio of cable elements and strain energy as objectives, and surface precision and natural frequency of cable-net as constraints. Sequential quadratic programming method is used to solve this nonlinear mathematical model in conditions with different weighting coefficients, and the results show the validity and effectiveness of the proposed method and model.

  12. Impurity confinement and transport in high confinement regimes without edge localized modes on DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    Grierson, B. A., E-mail:; Nazikian, R. M.; Solomon, W. M. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Burrell, K. H.; Garofalo, A. M.; Belli, E. A.; Staebler, G. M.; Evans, T. E.; Smith, S. P.; Chrobak, C. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Fenstermacher, M. E. [Lawerence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); McKee, G. R. [Department of Engineering Physics, University of Wisconsin-Madison, Madison, Wisconsin 53796 (United States); Orlov, D. M. [Center for Energy Research, University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0417 (United States); Chrystal, C. [University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0417 (United States)


    Impurity transport in the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] is investigated in stationary high confinement (H-mode) regimes without edge localized modes (ELMs). In plasmas maintained by resonant magnetic perturbation (RMP), ELM-suppression, and QH-mode, the confinement time of fluorine (Z = 9) is equivalent to that in ELMing discharges with 40 Hz ELMs. For selected discharges with impurity injection, the impurity particle confinement time compared to the energy confinement time is in the range of τ{sub p}/τ{sub e}≈2−3. In QH-mode operation, the impurity confinement time is shown to be smaller for intense, coherent magnetic, and density fluctuations of the edge harmonic oscillation than weaker fluctuations. Transport coefficients are derived from the time evolution of the impurity density profile and compared to neoclassical and turbulent transport models NEO and TGLF. Neoclassical transport of fluorine is found to be small compared to the experimental values. In the ELMing and RMP ELM-suppressed plasma, the impurity transport is affected by the presence of tearing modes. For radii larger than the mode radius, the TGLF diffusion coefficient is smaller than the experimental value by a factor of 2–3, while the convective velocity is within error estimates. Low levels of diffusion are observed for radii smaller than the tearing mode radius. In the QH-mode plasma investigated, the TGLF diffusion coefficient is higher inside of ρ=0.4 and lower outside of 0.4 than the experiment, and the TGLF convective velocity is more negative by a factor of approximately 1.7.

  13. Northern pike bycatch in an inland commercial hoop net fishery: effects of water temperature and net tending frequency on injury, physiology, and survival

    Energy Technology Data Exchange (ETDEWEB)

    Colotelo, Alison HA; Raby, Graham D.; Hasler, Caleb T.; Haxton, Tim; Smokorowski, Karen; Blouin-Demers, Gabriel; Cooke, Steven J.


    In lakes and rivers of eastern Ontario (Canada) commercial fishers use hoop nets to target a variety of fishes, but incidentally capture non-target (i.e., bycatch) gamefish species such as northern pike (Esox lucius). Little is known about the consequences of bycatch in inland commercial fisheries, making it difficult to identify regulatory options. Regulations that limit fishing during warmer periods and that require frequent net tending have been proposed as possible strategies to reduce bycatch mortality. Using northern pike as a model, we conducted experiments during two thermal periods (mid-April: 14.45 ± 0.32 °C, and late May: 17.17 ± 0.08 °C) where fish were retained in nets for 2 d and 6 d. A ‘0 d’ control group consisted of northern pike that were angled, immediately sampled and released. We evaluated injury, physiological status and mortality after the prescribed net retention period and for the surviving fish used radio telemetry with manual tracking to monitor delayed post-release mortality. Our experiments revealed that injury levels, in-net mortality, and post-release mortality tended to increase with net set duration and at higher temperatures. Pike exhibited signs of chronic stress and starvation following retention, particularly at higher temperatures. Total mortality rates were negligible for the 2 d holding period at 14 °C, 14% for 6 d holding at 14 °C, 21% for 2 d holding at 17 °C, and 58% for 6 d holding at 17 °C. No mortality was observed in control fish. Collectively, these data reveal that frequent net tending, particularly at warmer temperatures, may be useful for conserving gamefish populations captured as bycatch in inland hoop net fisheries.

  14. [Complex posttraumatic stress disorder]. (United States)

    Green, Tamar; Kotler, Moshe


    The characteristic symptoms resulting from exposure to an extreme trauma include three clusters of symptoms: persistent experience of the traumatic event, persistent avoidance of stimuli associated with the trauma and persistent symptoms of increased arousal. Beyond the accepted clusters of symptoms for posttraumatic stress disorder exists a formation of symptoms related to exposure to extreme or prolonged stress e.g. childhood abuse, physical violence, rape, and confinement within a concentration camp. With accumulated evidence of the existence of these symptoms began a trail to classify a more complex syndrome, which included, but was not confined to the symptoms of posttraumatic stress disorder. This review addresses several subjects for study in complex posttraumatic stress disorder, which is a complicated and controversial topic. Firstly, the concept of complex posttraumatic stress disorder is presented. Secondly, the professional literature relevant to this disturbance is reviewed and finally, the authors present the polemic being conducted between the researchers of posttraumatic disturbances regarding validity, reliability and the need for separate diagnosis for these symptoms.

  15. Alkalinity Enrichment Enhances Net Calcification of a Coral Reef Flat (United States)

    Albright, R.; Caldeira, K.


    Ocean acidification is projected to shift reefs from a state of net accretion to one of net dissolution sometime this century. While retrospective studies show large-scale changes in coral calcification over the last several decades, it is not possible to unequivocally link these results to ocean acidification due to confounding factors of temperature and other environmental parameters. Here, we quantified the calcification response of a coral reef flat to alkalinity enrichment to test whether reef calcification increases when ocean chemistry is restored to near pre-industrial conditions. We used sodium hydroxide (NaOH) to increase the total alkalinity of seawater flowing over a reef flat, with the aim of increasing carbonate ion concentrations [CO32-] and the aragonite saturation state (Ωarag) to values that would have been attained under pre-industrial atmospheric pCO2 levels. We developed a dual tracer regression method to estimate alkalinity uptake (i.e., calcification) in response to alkalinity enrichment. This approach uses the change in ratios between a non-conservative tracer (alkalinity) and a conservative tracer (a non-reactive dye, Rhodamine WT) to assess the fraction of added alkalinity that is taken up by the reef as a result of an induced increase in calcification rate. Using this method, we estimate that an average of 17.3% ± 2.3% of the added alkalinity was taken up by the reef community. In providing results from the first seawater chemistry manipulation experiment performed on a natural coral reef community (without artificial confinement), we demonstrate that, upon increase of [CO32-] and Ωarag to near pre-industrial values, reef calcification increases. Thus, we conclude that, the impacts of ocean acidification are already being felt by coral reefs. This work is the culmination of years of work in the Caldeira lab at the Carnegie Institution for Science, involving many people including Jack Silverman, Kenny Schneider, and Jana Maclaren.

  16. Zooplankton composition along the confinement gradient of the Taranto Sea System (Ionian Sea, south-eastern Italy) (United States)

    Belmonte, Genuario; Vaglio, Irene; Rubino, Fernando; Alabiso, Giorgio


    A 2-year study was conducted on 4 interconnected, progressively more confined coastal basins with the aim of describing zooplankton composition and its dynamics. A total of 346 taxa (175 species) were recorded. 24 species were new records for the Italian fauna. Taxa richness was partly attributed to the intense sampling effort. Using an additional net with narrower mesh sizes enabled to enrich the taxa list, and a correct estimation of the abundances, especially for the smaller species. Regarding spatial partitioning, 87.5% of categories were linked to only 1 or 2 adjacent sampling stations. Regarding time partitioning, 80.6% of categories showed an intermittent presence (seasonality). Distance from the open sea (confinement) was found to be directly correlated with the numerical abundance of specimens and its variability. In contrast, it was inversely correlated with species richness. Cumulative data after 2 years, confirmed the inverse correlation of species number with confinement. However, the final species richness led to less important differences between the four basins. A comparison with data from 1990 to 91 highlighted substantial differences in zooplankton composition. However, in one case it has been demonstrated that the difference was due to the difficulty in correctly estimating species number in confined habitats.

  17. Phenomenological sizes of confinement regions in baryons

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.E.; Klimt, S.; Weise, W.; Rho, M.


    Standard order of magnitude estimates from QCD indicate that the radius of the quark-gluon core in the nucleon is ..lambda../sup -1//sub QCD/ > or approx. 1 fm. However, in work with the chiral bag model, we have found that the effective confinement size for low energy reactions can be as small as approx. = 1/2 fm or smaller. This shrinking of the effective confinement size has been attributed to the pressure of the pion cloud surrounding the quark core. The concept of confinement size is evidently subtle in light-quark systems, due to the chiral vacuum structure. This is indicated by the 'Cheshire Cat' phenomenon, in which physical observables tend to be insensitive to the bag radius R. We suggest that when strange quarks are present, a qualitative change occurs in the Cheshire Cat picture; in particular, we propose that strangeness provides an obstruction to this picture. We present a phenomenological indication that when strange quarks are present, the bag radius R is frozen at a value substantially larger than 0.5 fm by as much as a factor of two. Roughly speaking, the Cheshire Cat picture emerges from a near cancellation between repulsive quark kinetic and attractive pion-cloud energies in the case of the nucleon. In the ..lambda.. and ..sigma.. particles, however, replacement of one up or down quark by a strange quark removes part of the attraction from the coupling of the quarks to the pion cloud. This upsets the balance needed for the Cheshire Cat phenomenon and makes larger strange baryons more favorable energetically than the 0.5 fm ones appropriate for pure u- and d-systems. We find that magnetic moments of strange baryons favor a bag radius R approx. = 1.1 fm. We find that the excited states of the ..lambda..-hyperons favor similarly large bag radii. Somewhat less convincingly, due to perturbative effects - the bag radius appropriate to the lies intermediate between that of the nucleon and of the stran

  18. What confines the rings of Saturn? (United States)

    Tajeddine, Radwan; Nicholson, Philip D.; El Moutamid, Maryame; Longaretti, Pierre-Yves; Burns, Joseph A.


    The viscous spreading of planetary rings is believed to be counteracted by satellite torques, either through an individual resonance or through overlapping resonances (when the satellite is close to the ring edge). For the A ring of Saturn, it has been commonly believed that the satellite Janus alone can prevent the ring from spreading via its 7:6 Lindblad resonance. We discuss this common misconception and show that, in reality, the A ring is confined by the contributions from the group of satellites Pan, Atlas, Prometheus, Pandora, Janus, Epimetheus, and Mimas, whose resonances gradually decrease the angular momentum flux transported outward through the ring via density and bending waves. We further argue that this decrease in angular momentum flux occurs through the mechanism of ‘flux reversal’.We find that the Janus 7:6 torque is relatively feeble, as is the comparable torque of the nearby small satellite Atlas, each amounting to less than one-tenth of the angular momentum transport carried by the A ring. But the cumulative torques of the many other satellite resonances in the A ring sufficiently reduce the angular momentum flux through the rings so that the torques due to Janus and Atlas are effective in confining the outer edge of the ring.Furthermore, we use the magnitude of the satellites’ resonance torques to estimate the effective viscosity profile across the A ring, showing that it decreases from ~50 cm2 s-1 at the inner edge to less than ~11 cm2 s-1 at the outer edge. The gradual estimated decrease of the angular momentum flux and effective viscosity are roughly consistent with results obtained by balancing the shepherding torques from Pan and Daphnis with the viscous torque at the edges of the Encke and Keeler gaps, as well as the edge of the A ring.On the other hand, the Mimas 2:1 Lindblad resonance alone seems to be capable of confining the edge of the B ring, and contrary to the situation in the A ring, we show that the effective viscosity


    Directory of Open Access Journals (Sweden)

    Rhafidilla Vebrynda


    Full Text Available Di dalam artikel ini, peneliti ingin melihat perkembangan teknologi di Indonesia sebagai sebuah peluang untuk menjalankan sebuah program berita berbasis video kiriman masyarakat. Perkembangan teknologi tersebut adalah teknologi penyiaran, teknologi sosial media dan teknologi dalam proses produksi sebuah video. Di Indonesia, jumlah televisi semakin banyak. Setiap stasiun televisi harus bersaing untuk dapat bertahan hidup. Net TV merupakan sebuah stasiun televisi baru di Indonesia yang harus memiliki berbagai program unggulan baru agar dapat bersaing dengan televisi lainnya yang sudah ada. Net TV menggunakan berbagai platform media untuk menjalankan program Net Citizen Journalism (Net CJ. Penggunaan berbagai platform media dikenal dengan istilah multiplatform dan secara teoritis dikenal dengan istilah konvergensi. Konvergensi yaitu saat meleburnya domain-domain dalam berbagai media komunikasi. Artikel ini menggunakan metode studi kasus untuk melihat bagaimana konvergensi terjadi dalam proses pengelolaan program Net CJ. Teknik pengumpulan data adalah dengan wawancara mendalam, observasi dan studi dokumen. Wawancara mendalam dilakukan dari tiga sudut pandang yaitu dari pengelola program, pengguna/audience dan pengamat media. Penelitian ini menemukan bahwa dengan menggunakan berbagai platform media yang fungsinya berbeda, memiliki satu tujuan yang sama yaitu untuk menjalankan program Net CJ. Adapun berbagai platform dalam proses produksi program yaitu tayangan TV konvensional, streaming TV, website, aplikasi Net CJ, facebook, twitter, instagram dan path. Konvergensi media dijalankan dalam dua proses, yaitu proses produksi dan proses promosi program berita.

  20. Net Neutrality: Media Discourses and Public Perception

    Directory of Open Access Journals (Sweden)

    Christine Quail


    Full Text Available This paper analyzes media and public discourses surrounding net neutrality, with particular attention to public utility philosophy, from a critical perspective. The article suggests that further public education about net neutrality would be beneficial. The first portion of this paper provides a survey of the existing literature surrounding net neutrality, highlighting the contentious debate between market-based and public interest perspectives. In order to contextualize the debate, an overview of public utility philosophy is provided, shedding light on how the Internet can be conceptualized as a public good. Following this discussion, an analysis of mainstream media is presented, exploring how the media represents the issue of net neutrality and whether or not the Internet is discussed through the lens of public utility. To further examine how the net neutrality debate is being addressed, and to see the potential impacts of media discourses on the general public, the results of a focus group are reported and analyzed. Finally, a discussion assesses the implications of the net neutrality debate as presented through media discourses, highlighting the future of net neutrality as an important policy issue.

  1. Approximation methods for stochastic petri nets (United States)

    Jungnitz, Hauke Joerg


    Stochastic Marked Graphs are a concurrent decision free formalism provided with a powerful synchronization mechanism generalizing conventional Fork Join Queueing Networks. In some particular cases the analysis of the throughput can be done analytically. Otherwise the analysis suffers from the classical state explosion problem. Embedded in the divide and conquer paradigm, approximation techniques are introduced for the analysis of stochastic marked graphs and Macroplace/Macrotransition-nets (MPMT-nets), a new subclass introduced herein. MPMT-nets are a subclass of Petri nets that allow limited choice, concurrency and sharing of resources. The modeling power of MPMT is much larger than that of marked graphs, e.g., MPMT-nets can model manufacturing flow lines with unreliable machines and dataflow graphs where choice and synchronization occur. The basic idea leads to the notion of a cut to split the original net system into two subnets. The cuts lead to two aggregated net systems where one of the subnets is reduced to a single transition. A further reduction leads to a basic skeleton. The generalization of the idea leads to multiple cuts, where single cuts can be applied recursively leading to a hierarchical decomposition. Based on the decomposition, a response time approximation technique for the performance analysis is introduced. Also, delay equivalence, which has previously been introduced in the context of marked graphs by Woodside et al., Marie's method and flow equivalent aggregation are applied to the aggregated net systems. The experimental results show that response time approximation converges quickly and shows reasonable accuracy in most cases. The convergence of Marie's method and flow equivalent aggregation are applied to the aggregated net systems. The experimental results show that response time approximation converges quickly and shows reasonable accuracy in most cases. The convergence of Marie's is slower, but the accuracy is generally better. Delay

  2. Thermo-diffusion in inertially confined plasmas

    CERN Document Server

    Kagan, Grigory


    In a plasma of multiple ion species, thermodynamic forces such as pressure and temperature gradients can drive ion species separation via inter-species diffusion. Unlike its neutral mix counterpart, plasma thermo-diffusion is found comparable to, or even much larger than, baro-diffusion. It is shown that such a strong effect is due to the long-range nature of the Coulomb potential, as opposed to short-range interactions in neutral gases. A special composition of the tritium and 3He fuel is identified to have vanishing net diffusion during adiabatic compression, and hence provides an experimental test in which yield degradation is minimized during ICF implosions.

  3. Visual Studio 2010 and NET 4 Six-in-One

    CERN Document Server

    Novak, Istvan; Granicz, Adam


    Complete coverage of all key .NET 4 and Visual Studio 2010 languages and technologies. .NET 4 is Microsoft's latest version of their core programming platform, and Visual Studio 2010 is the toolset that helps write .NET 4 applications. This comprehensive resource offers one-stop shopping for all you need to know to get productive with .NET 4. Experienced author and .NET guru Mitchel Sellers reviews all the important new features of .NET 4, including .NET charting and ASP.NET charting, ASP.NET dynamic data and jQuery, and the addition of F# as a supported package language. The expansive coverag

  4. Duality and Confinement in Massive Antisymmetric Tensor Gauge Theories

    CERN Document Server

    Diamantini, M Cristina


    We extend the duality between massive and topologically massive antisymmetric tensor gauge theories in arbitrary space-time dimensions to include topological defects. We show explicitly that the condensation of these defects leads, in 4 dimensions, to confinement of electric strings in the two dual models. The dual phase, in which magnetic strings are confined is absent. The presence of the confinement phase explicitely found in the 4-dimensional case, is generalized, using duality arguments, to arbitrary space-time dimensions.

  5. Net Neutrality: A Fast Lane to Understanding the Trade-offs


    Valletti, T; Peitz, M; Greenstein, S


    The "net neutrality" principle has triggered a heated debate and advocates have proposed policy interventions. In this paper, we provide perspective by framing issues in terms of the positive economic factors at work. We stress the incentives of market participants, and highlight the economic conflicts behind the arguments put forward by the different parties. We also identify several key open questions.

  6. Application and Theory of Petri Nets

    DEFF Research Database (Denmark)

    , the conferences have 150-200 participants, one third of these coming from industry and the rest from universities and research institutions. The 1992 conference was organized by the School of Computing and Management Sciences at Sheffield City Polytechnic, England. The volume contains twoinvited papers, by G......This volume contains the proceedings of the 13th International Conference onApplication and Theory of Petri Nets, held in Sheffield, England, in June 1992. The aim of the Petri net conferences is to create a forum for discussing progress in the application and theory of Petri nets. Typically...

  7. Performance Analysis using Coloured Petri Nets

    DEFF Research Database (Denmark)

    Wells, Lisa Marie

    an explicit separation between modelling the behaviour of a system and monitoring the behaviour of the model. As a result, cleaner and more understandable models can be created. The third paper presents a novel method for adding auxiliary information to coloured Petri net models. Coloured Petri nets models...... in a very limited and predictable manner, and it is easy to enable and disable the auxiliary information. The fourth paper is a case study in which the performance of a web server was analysed using coloured Petri nets. This case study has shown that it is relatively easy to analyse the performance...

  8. The KM3NeT project

    Energy Technology Data Exchange (ETDEWEB)

    Katz, U.F., E-mail: katz@physik.uni-erlangen.d [Erlangen Centre for Astroparticle Physics (ECAP), University of Erlangen-Nuernberg, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany)


    The KM3NeT research infrastructure in the deep Mediterranean Sea will host a multi-cubic-kilometre neutrino telescope and provide connectivity for continuous, long-term measurements of earth and sea sciences, such as geology, marine biology and oceanography. The KM3NeT neutrino telescope will complement the IceCube telescope currently being installed at the South Pole in its field of view and surpass its sensitivity by a substantial factor. In this document the major aspects of the KM3NeT technical design are described and the expected physics sensitivity is discussed. Finally, the expected time line towards construction is presented.

  9. The net neutrality debate on Twitter

    Directory of Open Access Journals (Sweden)

    Wolf J. Schünemann


    Full Text Available The internet has been seen as a medium that empowers individual political actors in relation to established political elites and media gatekeepers. The present article discusses this “net empowerment hypothesis” and tests it empirically by analysing Twitter communication on the regulation of net neutrality. We extracted 503.839 tweets containing #NetNeutrality posted between January and March 2015 and analysed central developments and the network structure of the debate. The empirical results show that traditional actors from media and politics still maintain a central role.

  10. Generalized Lawson Criteria for Inertial Confinement Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Tipton, Robert E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    The Lawson Criterion was proposed by John D. Lawson in 1955 as a general measure of the conditions necessary for a magnetic fusion device to reach thermonuclear ignition. Over the years, similar ignition criteria have been proposed which would be suitable for Inertial Confinement Fusion (ICF) designs. This paper will compare and contrast several ICF ignition criteria based on Lawson’s original ideas. Both analytical and numerical results will be presented which will demonstrate that although the various criteria differ in some details, they are closely related and perform similarly as ignition criteria. A simple approximation will also be presented which allows the inference of each ignition parameter directly from the measured data taken on most shots fired at the National Ignition Facility (NIF) with a minimum reliance on computer simulations. Evidence will be presented which indicates that the experimentally inferred ignition parameters on the best NIF shots are very close to the ignition threshold.

  11. Ultra-Compact Electrostatic Confinement Fusion Device (United States)

    Young, Garrett


    A unique, linear dual-beam configuration with an internal volume of 144 cc was simulated and operated. Deuteron ion paths were simulated using Mathematica and the electric field distribution was optimized relative to convergence density, potential well efficiency, and confinement time. The resulting cathode design is a departure from conventional systems, with gradual conical surfaces. The simulated trajectories correlated well to the observed operation, evidenced by two principle factors. First, the high transparency of the cathode due to the focused beams allowed for >1 kW operation without duration-limiting temperature rise. Second, when compared to inertial electrostatic configurations, the constructed device achieved record steady-state D-D fusion rates per internal volume including 3.7E +4 fusions/sec/cc at 52 kV applied potential and 28 mTorr operating pressure.

  12. Morphogenesis of filaments growing in flexible confinements (United States)

    Vetter, R.; Wittel, F. K.; Herrmann, H. J.


    Space-saving design is a requirement that is encountered in biological systems and the development of modern technological devices alike. Many living organisms dynamically pack their polymer chains, filaments or membranes inside deformable vesicles or soft tissue-like cell walls, chorions and buds. Surprisingly little is known about morphogenesis due to growth in flexible confinements—perhaps owing to the daunting complexity lying in the nonlinear feedback between packed material and expandable cavity. Here we show by experiments and simulations how geometric and material properties lead to a plethora of morphologies when elastic filaments are growing far beyond the equilibrium size of a flexible thin sheet they are confined in. Depending on friction, sheet flexibility and thickness, we identify four distinct morphological phases emerging from bifurcation and present the corresponding phase diagram. Four order parameters quantifying the transitions between these phases are proposed.

  13. A new discipline: Confined Areas Medicine

    Directory of Open Access Journals (Sweden)

    Stefano Agostinis


    Full Text Available The Confined Areas Medicine is a new discipline devoted to a specific branch of the components of emergency services. In it convey the characteristics typical of behavioral intervention in hostile area peculiar of the National Fire Corps and the National Speleological and Alpine Corps. While not considering the natural events that cause the collapse of housing the Italian case reported in the last fifty years about two hundred structural collapses that are charged over a thousand deaths (source: ISTAT 2006. Analysis of the documents accessible to the public today we can say without fear of denials, that 25% of these deaths are due to relief late or ineffective treatment on the spot. In fact, the NFPA (National Fire Protection Association claims that 10% of victims trapped under the rubble can be saved with a location and an early recovery, which can significantly increase this percentage with the health care stabilization directly at the place of discovery.

  14. Modeling collective cell migration in geometric confinement (United States)

    Tarle, Victoria; Gauquelin, Estelle; Vedula, S. R. K.; D'Alessandro, Joseph; Lim, C. T.; Ladoux, Benoit; Gov, Nir S.


    Monolayer expansion has generated great interest as a model system to study collective cell migration. During such an expansion the culture front often develops ‘fingers’, which we have recently modeled using a proposed feedback between the curvature of the monolayer’s leading edge and the outward motility of the edge cells. We show that this model is able to explain the puzzling observed increase of collective cellular migration speed of a monolayer expanding into thin stripes, as well as describe the behavior within different confining geometries that were recently observed in experiments. These comparisons give support to the model and emphasize the role played by the edge cells and the edge shape during collective cell motion.

  15. Confining standing waves in optical corrals. (United States)

    Babayan, Yelizaveta; McMahon, Jeffrey M; Li, Shuzhou; Gray, Stephen K; Schatz, George C; Odom, Teri W


    Near-field scanning optical microscopy images of solid wall, circular, and elliptical microscale corrals show standing wave patterns confined inside the structures with a wavelength close to that of the incident light. The patterns inside the corrals can be tuned by changing the size and material of the walls, the wavelength of incident light, and polarization direction for elliptical corrals. Finite-difference time-domain calculations of the corral structures agree with the experimental observations and reveal that the electric and magnetic field intensities are out of phase inside the corral. A theoretical modal analysis indicates that the fields inside the corrals can be attributed to p- and s-polarized waveguide modes, and that the superposition of the propagating and evanescent modes can explain the phase differences between the fields. These experimental and theoretical results demonstrate that electromagnetic fields on a dielectric surface can be controlled in a predictable manner.

  16. Topological Spin Textures in Confined Geometries (United States)

    Zang, Jiadong

    The magnetic skyrmion is a nanostructured spin texture stabilized by the spin-orbital coupling. Its nontrivial topology enables unique dynamical property and thermal stability, which give out promise on future magnetic memory devise. However, to enable its applications, it is essential to understand the skyrmion properties in confined geometries and tackle key challenges including the creation and detection of skyrmions, preferably without magnetic fields. In this talk, I will present our recent theory-experiment collaboration results, covering studies of skyrmions in nanoribbon, nanodisk, and nanowires. Zero field skyrmions and their polarization switch will be discussed. New skyrmion materials and new topological textures in helimagnet heterostructures will be presented. This work is supported by the Grant DE-SC0016424 funded by the U.S. Department of Energy, Office of Science.

  17. Dancing disclinations in confined active nematics (United States)

    Shendruk, Tyler N.; Doostmohammadi, Amin; Thijssen, Kristian; Yeomans, Julia M.

    The spontaneous emergence of collective flows is a generic property of active fluids and often leads to chaotic flow patterns characterised by swirls, jets, and topological disclinations in their orientation field. However, the ability to achieve structured flows and ordered disclinations is of particular importance in the design and control of active systems. By confining an active nematic fluid within a channel, we find a regular motion of disclinations, in conjunction with a well defined and dynamic vortex lattice. As pairs of moving disclinations travel through the channel, they continually exchange partners producing a dynamic ordered state, reminiscent of Ceilidh dancing. We anticipate that this biomimetic ability to self-assemble organised topological disclinations and dynamically structured flow fields in engineered geometries will pave the road towards establishing new active topological microfluidic devices.

  18. Dancing droplets: Contact angle, drag, and confinement (United States)

    Benusiglio, Adrien; Cira, Nate; Prakash, Manu


    When deposited on a clean glass slide, a mixture of water and propylene glycol forms a droplet of given contact angle, when both pure liquids spread. (Cira, Benusiglio, Prakash: Nature, 2015). The droplet is stabilized by a gradient of surface tension due to evaporation that induces a Marangoni flow from the border to the apex of the droplets. The apparent contact angle of the droplets depends on both their composition and the external humidity as captured by simple models. These droplets present remarkable properties such as lack of a large pinning force. We discuss the drag on these droplets as a function of various parameters. We show theoretical and experimental results of how various confinement geometries change the vapor gradient and the dynamics of droplet attraction.

  19. The theory of toroidally confined plasmas

    CERN Document Server

    White, Roscoe B


    This graduate level textbook develops the theory of magnetically confined plasma, with the aim of bringing the reader to the level of current research in the field of thermonuclear fusion. It begins with the basic concepts of magnetic field description, plasma equilibria and stability, and goes on to derive the equations for guiding center particle motion in an equilibrium field. Topics include linear and nonlinear ideal and resistive modes and particle transport. It is of use to workers in the field of fusion both for its wide-ranging account of tokamak physics and as a kind of handbook or formulary. This edition has been extended in a number of ways. The material on mode-particle interactions has been reformulated and much new information added, including methodology for Monte Carlo implementation of mode destabilization. These results give explicit means of carrying out mode destabilization analysis, in particular for the dangerous fishbone mode. A new chapter on cyclotron motion in toroidal geometry has ...

  20. Structure of charged polymer chains in confined geometry.

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, E. P.; Auvray, L.; Lal, J.


    The intra- and interchain structure of sodium poly(styrenesulphonate) when free and when confined in contrast matched porous Vycor has been investigated by SANS. When confined, a peak is observed whose intensity increases with molecular weight and the 1/q scattering region is extended compared to the bulk. We infer that the chains are sufficiently extended, under the influence of confinement, to highlight the large scale disordered structure of Vycor. The asymptotic behavior of the observed interchain structure factor is = 1/q{sup 2} and = 1/q for free and confined chains respectively.

  1. Cancer cell motility: lessons from migration in confined spaces (United States)

    Paul, Colin D.; Mistriotis, Panagiotis; Konstantopoulos, Konstantinos


    Time-lapse, deep-tissue imaging made possible by advances in intravital microscopy has demonstrated the importance of tumour cell migration through confining tracks in vivo. These tracks may either be endogenous features of tissues or be created by tumour or tumour-associated cells. Importantly, migration mechanisms through confining microenvironments are not predicted by 2D migration assays. Engineered in vitro models have been used to delineate the mechanisms of cell motility through confining spaces encountered in vivo. Understanding cancer cell locomotion through physiologically relevant confining tracks could be useful in developing therapeutic strategies to combat metastasis. PMID:27909339

  2. The cruel and unusual phenomenology of solitary confinement. (United States)

    Gallagher, Shaun


    What happens when subjects are deprived of intersubjective contact? This paper looks closely at the phenomenology and psychology of one example of that deprivation: solitary confinement. It also puts the phenomenology and psychology of solitary confinement to use in the legal context. Not only is there no consensus on whether solitary confinement is a "cruel and unusual punishment," there is no consensus on the definition of the term "cruel" in the use of that legal phrase. I argue that we can find a moral consensus on the meaning of "cruelty" by looking specifically at the phenomenology and psychology of solitary confinement.

  3. High beta and confinement studies on TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Navratil, G.A.; Bhattacharjee, A.; Iacono, R.; Mauel, M.E.; Sabbagh, S.A. (Columbia Univ., New York, NY (United States)); Kesner, J. (Massachusetts Inst. of Tech., Cambridge, MA (United States))


    A new regime of high poloidal beta operation in TFTR was developed in the course of the first two years of this project (9/25/89 to 9/24/91). Our proposal to continue this successful collaboration between Columbia University and the Massachusetts Institute of Technology with the Princeton Plasma Physics Laboratory for a three year period (9/25/91 to 9/24/94) to continue to investigate improved confinement and tokamak performance in high poloidal beta plasmas in TFTR through the DT phase of operation was approved by the DOE and this is a report of our progress during the first 9 month budget period of the three year grant (9/25/91 to 6/24/92). During the approved three year project period we plan to (1) extend and apply the low current, high QDD discharges to the operation of TFTR using Deuterium and Tritium plasma; (2) continue the analysis and plan experiments on high poloidal beta phenomena in TFTR including: stability properties, enhanced global confinement, local transport, bootstrap current, and divertor formation; (3) plan and carry out experiments on TFTR which attempt to elevate the central q to values > 2 where entry to the second stability regime is predicted to occur; and (4) collaborate on high beta experiments using bean-shaped plasmas with a stabilizing conducting shell in PBX-M. In the seven month period covered by this report we have made progress in each of these four areas through the submission of 4 TFTR Experimental Proposals and the partial execution of 3 of these using a total of 4.5 run days during the August 1991 to February 1992 run.

  4. Free Energy of a Polymer in Slit-Like Confinement across the Odijk, moderate confinement, and Bulk Regimes (United States)

    Kamanzi, Albert; Leith, Jason S.; Sean, David; Berard, Daniel; Guthrie, Andrew C.; McFaul, Christopher M. J.; Slater, Gary W.; de Haan, Hendrick W.; Leslie, Sabrina R.; McGill University Team; University of Ottawa, University of Ontario Collaboration

    We directly measure the free energy of confinement for semi-flexible polymers from the nanoscale to bulk regimes in slit-like confinement. We use Convex Lens-induced Confinement (CLiC) microscopy of DNA to load and directly count molecules at equilibrium in a single chamber of smoothly increasing height. CLiC microscopy allows for direct visualization of polymers in free solution over long periods, as a function of tunable vertical confinement - from the millimeter to the nanometer scale, and within a single device. Our direct characterization of the free energy of confinement, across several orders of magnitude of applied confinement, agree with new simulations established in this work. We compare experimental results to the ``de Gennes blob model'', to theory published by Casassa, as well as to simulations by Chen and Sullivan, in appropriate regimes. This work establishes a robust platform for understanding and manipulating polymers at the nanoscale, with a wide range of applications to biomedical technologies.

  5. Reconsidering the effects of poverty and social support on health: a 5-year longitudinal test of the stress-buffering hypothesis. (United States)

    Moskowitz, David; Vittinghoff, Eric; Schmidt, Laura


    Prior research in the general population has found that social support can buffer the adverse effects of stressors on health. However, both stressors and social support may be qualitatively different for those living in urban poverty. We examined the effects of social support and poverty-specific stressors on self-rated health. We used data from the Welfare Client Longitudinal Survey (WCLS), a 5-year longitudinal study of 718 public aid recipients. We measured received social support and "net social support," defined as the difference between support received and that given to others. We used restricted cubic splines to model the stress-buffering effects of social support on self-rated health as a function of stressful life events and neighborhood disorder. Increased exposure to stressors was associated with poorer self-rated health. Evidence of stress buffering was confined to those with the heaviest exposure to stressors, and its effects decreased across increasing levels of social support. Analyses using net social support had generally more modest effects than those using received social support. Social support does not buffer the effects of stressors on health uniformly for individuals living in conditions of urban poverty. Researchers and policymakers should be cautious in overestimating the beneficial effects that social support may have on health for marginalized populations.

  6. Planning long lasting insecticide treated net campaigns: should households' existing nets be taken into account? (United States)

    Yukich, Joshua; Bennett, Adam; Keating, Joseph; Yukich, Rudy K; Lynch, Matt; Eisele, Thomas P; Kolaczinski, Kate


    Mass distribution of long-lasting insecticide treated bed nets (LLINs) has led to large increases in LLIN coverage in many African countries. As LLIN ownership levels increase, planners of future mass distributions face the challenge of deciding whether to ignore the nets already owned by households or to take these into account and attempt to target individuals or households without nets. Taking existing nets into account would reduce commodity costs but require more sophisticated, and potentially more costly, distribution procedures. The decision may also have implications for the average age of nets in use and therefore on the maintenance of universal LLIN coverage over time. A stochastic simulation model based on the NetCALC algorithm was used to determine the scenarios under which it would be cost saving to take existing nets into account, and the potential effects of doing so on the age profile of LLINs owned. The model accounted for variability in timing of distributions, concomitant use of continuous distribution systems, population growth, sampling error in pre-campaign coverage surveys, variable net 'decay' parameters and other factors including the feasibility and accuracy of identifying existing nets in the field. Results indicate that (i) where pre-campaign coverage is around 40% (of households owning at least 1 LLIN), accounting for existing nets in the campaign will have little effect on the mean age of the net population and (ii) even at pre-campaign coverage levels above 40%, an approach that reduces LLIN distribution requirements by taking existing nets into account may have only a small chance of being cost-saving overall, depending largely on the feasibility of identifying nets in the field. Based on existing literature the epidemiological implications of such a strategy is likely to vary by transmission setting, and the risks of leaving older nets in the field when accounting for existing nets must be considered. Where pre-campaign coverage

  7. Planning long lasting insecticide treated net campaigns: should households’ existing nets be taken into account? (United States)


    Background Mass distribution of long-lasting insecticide treated bed nets (LLINs) has led to large increases in LLIN coverage in many African countries. As LLIN ownership levels increase, planners of future mass distributions face the challenge of deciding whether to ignore the nets already owned by households or to take these into account and attempt to target individuals or households without nets. Taking existing nets into account would reduce commodity costs but require more sophisticated, and potentially more costly, distribution procedures. The decision may also have implications for the average age of nets in use and therefore on the maintenance of universal LLIN coverage over time. Methods A stochastic simulation model based on the NetCALC algorithm was used to determine the scenarios under which it would be cost saving to take existing nets into account, and the potential effects of doing so on the age profile of LLINs owned. The model accounted for variability in timing of distributions, concomitant use of continuous distribution systems, population growth, sampling error in pre-campaign coverage surveys, variable net ‘decay’ parameters and other factors including the feasibility and accuracy of identifying existing nets in the field. Results Results indicate that (i) where pre-campaign coverage is around 40% (of households owning at least 1 LLIN), accounting for existing nets in the campaign will have little effect on the mean age of the net population and (ii) even at pre-campaign coverage levels above 40%, an approach that reduces LLIN distribution requirements by taking existing nets into account may have only a small chance of being cost-saving overall, depending largely on the feasibility of identifying nets in the field. Based on existing literature the epidemiological implications of such a strategy is likely to vary by transmission setting, and the risks of leaving older nets in the field when accounting for existing nets must be considered

  8. RadNet Air Quality (Deployable) Data (United States)

    U.S. Environmental Protection Agency — RadNet Deployable Monitoring is designed to collect radiological and meteorological information and data asset needed to establish the impact of radiation levels on...

  9. A Lightweight TwiddleNet Portal

    National Research Council Canada - National Science Library

    Rimikis, Antonios M


    TwiddleNet is a distributed architecture of personal servers that harnesses the power of the mobile devices, enabling real time information and file sharing of multiple data types from commercial-off-the-shelf platforms...

  10. Homology Groups of a Pipeline Petri Net

    Directory of Open Access Journals (Sweden)

    A. A. Husainov


    Full Text Available Petri net is said to be elementary if every place can contain no more than one token. In this paper, it is studied topological properties of the elementary Petri net for a pipeline consisting of n functional devices. If the work of the functional devices is considered continuous, we can come to some topological space of “intermediate” states. In the paper, it is calculated the homology groups of this topological space. By induction on n, using the Addition Sequence for homology groups of semicubical sets, it is proved that in dimension 0 and 1 the integer homology groups of these nets are equal to the group of integers, and in the remaining dimensions are zero. Directed homology groups are studied. A connection of these groups with deadlocks and newsletters is found. This helps to prove that all directed homology groups of the pipeline elementary Petri nets are zeroth.

  11. Stress Compensating Multilayers (United States)

    Broadway, David M.; Ramsey, Brian D.; O'dell, Stephen; Gurgew, Danielle


    We present in-situ stress measurement results for single and multilayer thin-films deposited by magnetron sputtering. In particular, we report on the influence of the material interfaces on the ensuing stress in both the transient and steady-state regimes of film growth. This behavior is used to determine the appropriate thicknesses of the constituent layers that will result in a net tensile stress in multilayers composed of various material combinations. These multilayers can then be used to compensate the compressive integrated stress in single and multilayer EUV and x-ray optical coatings. The use of multilayers to compensate the integrated stress might be advantageous because, unlike single layers of chromium, the roughness is not expected to increase with the total thickness of the multilayer. In this paper, we demonstrate the technique for W/Si and Mo/Si multilayers and discuss its application to other material combinations.

  12. Net accumulation of the Greenland ice sheet

    DEFF Research Database (Denmark)

    Kiilsholm, Sissi; Christensen, Jens Hesselbjerg; Dethloff, Klaus


    improvement compared to the driving OAGCM. Estimates of the regional net balance are also better represented by the RCM. In the future climate the net balance for the Greenland Ice Sheet is reduced in all the simulation, but discrepancies between the amounts when based on ECHAM4/OPYC3 and HIRHAM are found....... In both scenarios, the estimated melt rates are larger in HIRHAM than in the driving model....

  13. CDMA and TDMA based neural nets. (United States)

    Herrero, J C


    CDMA and TDMA telecommunication techniques were established long time ago, but they have acquired a renewed presence due to the rapidly increasing mobile phones demand. In this paper, we are going to see they are suitable for neural nets, if we leave the concept "connection" between processing units and we adopt the concept "messages" exchanged between them. This may open the door to neural nets with a higher number of processing units and flexible configuration.

  14. Mastering AngularJD for .NET developers

    CERN Document Server

    Majid, Mohammad Wadood


    This book is envisioned for traditional developers and programmers who want to develop client-side applications using the AngularJS framework and ASP.NET Web API 2 with Visual Studio. .NET developers who have already built web applications or web services and who have a fundamental knowledge of HTML, JavaScript, and CSS and want to explore single-page applications will also find this guide useful. Basic knowledge of AngularJS would be helpful.

  15. .NET 4.5 parallel extensions

    CERN Document Server

    Freeman, Bryan


    This book contains practical recipes on everything you will need to create task-based parallel programs using C#, .NET 4.5, and Visual Studio. The book is packed with illustrated code examples to create scalable programs.This book is intended to help experienced C# developers write applications that leverage the power of modern multicore processors. It provides the necessary knowledge for an experienced C# developer to work with .NET parallelism APIs. Previous experience of writing multithreaded applications is not necessary.

  16. A Lightweight TwiddleNet Portal (United States)


    designed to exploit the multiple networking modalities available in the current generation of smartphones . TwiddleNet enables well-organized and well...of Sonopia and will have a comprehensive review of the service in the coming weeks [12]. Twango, which was acquired by Nokia in July 2007, is an...EXPERIMENTATION As already mentioned the main purpose of this thesis is the development of a TwiddleNet portal running on a smartphone or a PDA, which can allow

  17. CCS - and its relationship to net theory

    DEFF Research Database (Denmark)

    Nielsen, Mogens


    In this paper we give a short introduction to Milner's Calculus for Communicating Systems - a paradigm for concurrent computation. We put special emphasis on the basic concepts and tools from the underlying "algebraic approach", and their relationship to the approach to concurrency within net...... theory. Furthermore, we provide an operational version of the language CCS with "true concurrency" in the sense of net theory, and a discussion of the possible use of such a marriage of the two theories of concurrency....

  18. Visual Studio 2013 and .NET 4.5 expert cookbook

    CERN Document Server

    Sur, Abhishek


    If you are a Visual Studio 2013 or .NET developer who would like to sharpen your existing skill set and adapt to new .NET technologies, this is the book for you. A basic understanding of .NET and C# is required.

  19. HANPP Collection: Global Patterns in Net Primary Productivity (NPP) (United States)

    National Aeronautics and Space Administration — The Global Patterns in Net Primary Productivity (NPP) portion of the Human Appropriation of Net Primary Productivity (HANPP) Collection maps the net amount of solar...

  20. Dissipation of coherent structures in confined two-dimensional turbulence (United States)

    Clercx, H. J. H.; van Heijst, G. J. F.


    Since the seminal article "Inertial ranges in two-dimensional turbulence" by Kraichnan in 1967, our understanding of the dynamics and transport properties of two-dimensional turbulence is largely built on the assumption of homogeneity and isotropy of statistically steady or decaying turbulence. In the last two decades, more attention has been paid to the presence of lateral walls, either with stress-free or no-slip boundary conditions, and also considering a variety of geometries such as square, rectangular, or circular domains. The impact of confining boundaries on the dynamics of two-dimensional turbulence is important. This is in sharp contrast with three-dimensional turbulence, where homogeneity and isotropy are locally restored due to the cascade process in the inertial range. The impact of confining boundaries is therefore limited in three-dimensional turbulence. The presence of an inverse energy cascade in two-dimensional turbulence, however, will continuously generate large-scale energy-containing eddies, and their vigorous interaction with, in particular, no-slip walls generates large amounts of vorticity and contributes significantly to the dissipation of kinetic energy of the flow. The dissipation is even strongly enhanced compared with the unbounded case. In this review, we will focus on one of the elementary structures observed in two-dimensional turbulent flows: the dipolar vortex. With its self-induced velocity, it propagates easily through the domain and is hence likely to interact with domain boundaries. Standard vortex generation mechanisms allow to create well-defined dipoles and to investigate the collision of such structures with rigid domain boundaries in detail. Relevant aspects of the collision process concern the dynamics and stability of the generated boundary layers, the vorticity, and vorticity gradients contained in these boundary layers, and the dissipation of kinetic energy when dipoles collide with walls. Some of these aspects will

  1. ASP.NET web API build RESTful web applications and services on the .NET framework

    CERN Document Server

    Kanjilal, Joydip


    This book is a step-by-step, practical tutorial with a simple approach to help you build RESTful web applications and services on the .NET framework quickly and efficiently.This book is for ASP.NET web developers who want to explore REST-based services with C# 5. This book contains many real-world code examples with explanations whenever necessary. Some experience with C# and ASP.NET 4 is expected.

  2. DFT reactivity indices in confined many-electron atoms

    Indian Academy of Sciences (India)

    , global hardness and softness are reported for a representative set of spherically confined atoms of IA, IIA, VA and VIIIA series in the periodic table. The atomic electrons are confined within the impenetrable spherical cavity defined by a given ...

  3. Investigation of stress–strain models for confined high strength ...

    Indian Academy of Sciences (India)

    The ascending branch of stress–strain curves depended on the ratio of confinement reinforcement was similar to the modified Kent–Park model and the descending branch similar to the Nagashima model. Keywords. High strength concrete; confined concrete; stress–strain models; ductility toughness. 1. Introduction.

  4. Confinement, average forces, and the Ehrenfest theorem for a one ...

    Indian Academy of Sciences (India)

    The topics of confinement, average forces, and the Ehrenfest theorem are examined for a particle in one spatial dimension. Two specific cases are considered: A free particle moving on the entire real line, which is then permanently confined to a line segment or `a box' (this situation is achieved by taking the limit V 0 → ∞ in ...

  5. Inclusion of biotic stress (consumer pressure) alters predictions from the stress gradient hypothesis

    NARCIS (Netherlands)

    Smit, Christian; Rietkerk, Max; Wassen, Martin J.


    The stress gradient hypothesis (SGH) predicts a shift from net negative interactions in benign environments towards net positive in harsh environments in ecological communities. While several studies found support for the SGH, others found evidence against it, leading to a debate on how nature and

  6. Freeze-out conditions from net-proton and net-charge fluctuations at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Alba, Paolo; Alberico, Wanda [Department of Physics, Torino University and INFN, Sezione di Torino, via P. Giuria 1, 10125 Torino (Italy); Bellwied, Rene [Department of Physics, University of Houston, Houston, TX 77204 (United States); Bluhm, Marcus [Department of Physics, Torino University and INFN, Sezione di Torino, via P. Giuria 1, 10125 Torino (Italy); Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States); Mantovani Sarti, Valentina [Department of Physics, Torino University and INFN, Sezione di Torino, via P. Giuria 1, 10125 Torino (Italy); Nahrgang, Marlene [Department of Physics, Duke University, Durham, NC 27708-0305 (United States); Frankfurt Institute for Advanced Studies (FIAS), Ruth-Moufang-Str. 1, 60438 Frankfurt am Main (Germany); Ratti, Claudia [Department of Physics, Torino University and INFN, Sezione di Torino, via P. Giuria 1, 10125 Torino (Italy)


    We calculate ratios of higher-order susceptibilities quantifying fluctuations in the number of net-protons and in the net-electric charge using the Hadron Resonance Gas (HRG) model. We take into account the effect of resonance decays, the kinematic acceptance cuts in rapidity, pseudo-rapidity and transverse momentum used in the experimental analysis, as well as a randomization of the isospin of nucleons in the hadronic phase. By comparing these results to the latest experimental data from the STAR Collaboration, we determine the freeze-out conditions from net-electric charge and net-proton distributions and discuss their consistency.

  7. Dynamic mechanical properties and anisotropy of synthetic shales with different clay minerals under confining pressure (United States)

    Gong, Fei; Di, Bangrang; Wei, Jianxin; Ding, Pinbo; Shuai, Da


    The presence of clay minerals can alter the elastic behaviour of reservoir rocks significantly as the type of clay minerals, their volume and distribution, and their orientation control the shale's intrinsic anisotropic behaviours. Clay minerals are the most abundant materials in shale, and it has been proven extremely difficult to measure the elastic properties of natural shale by means of a single variable (in this case, the type of clay minerals), due to the influences of multiple factors, including water, TOC content and complex mineral compositions. We used quartz, clay (kaolinite, illite and smectite), carbonate and kerogen extract as the primary materials to construct synthetic shale with different clay minerals. Ultrasonic experiments were conducted to investigate the anisotropy of velocity and mechanical properties in dry synthetic and natural shale as a function of confining pressure. Velocities in synthetic shale are sensitive to the type of clay minerals, possibly due to the different structures of the clay minerals. The velocities increase with confining pressure and show higher rate of velocity increase at low pressures, and P-wave velocity is usually more sensitive than S-wave velocity to confining pressure according to our results. Similarly, the dynamic Young's modulus and Poisson's ratio increase with applied pressure, and the results also reveal that E11 is always larger than E33 and ν31 is smaller than ν12. Velocity and mechanical anisotropy decrease with increasing stress, and are sensitive to stress and the type of clay minerals. However, the changes of mechanical anisotropy with applied stress are larger compared with the velocity anisotropy, indicating that mechanical properties are more sensitive to the change of rock properties.

  8. Dynamical properties of nimodipine molecules confined in SBA-15 matrix (United States)

    Kiwilsza, A.; Pajzderska, A.; Mielcarek, J.; Jenczyk, J.; Wąsicki, J.


    The paper reports results of 13C and 1H ssNMR for nimodipine confined in mesopores of SBA-15 for the samples (i) containing nimodipine molecules inside and on the external surface of silica, (ii) containing nimodipine only inside pores forming an incomplete monolayer on the surface (iii) for bulk nimodipine. The measurements permitted comparison of the dynamics of nimodipine bulk and confined in pores. The confined nimodipine is in an amorphous state and has additional degrees of rotational freedom with respect to the bulk one. The height of the energy barrier related to the rotation of methyl groups in confined nimodipine is lower than in bulk nimodipine. The higher mobility of nimodipine molecules confined in silica pores can explain the higher release rate of nimodipine from silica matrix than dissolution rate of bulk drug.

  9. Confined space entry program for the Westinghouse Hanford Company

    Energy Technology Data Exchange (ETDEWEB)

    Cornell, T.M.


    To comply with anticipated OSHA regulatory requirements concerning Permit-Required Confined Spaces, Westinghouse Hanford Company (WHC) created a Confined Spaces Task Team. The primary focus of the task team was to prepare a formal Confined Space Entry (CSE) Program that would ensure full compliance with the anticipated OSHA requirements. A comprehensive training plan was also prepared and submitted for approval as soon as the new CSE Program was approved and released for implementation. On January 14, 1993, OSHA released their final ruling which contained several further changes, requiring the WHC Confined Space Entry Program and Training Plan to be revised. The revised training manual and lessons learned in establishing a Confined Space Entry Program are presented.

  10. Diffusion of Finite-Size Particles in Confined Geometries

    KAUST Repository

    Bruna, Maria


    The diffusion of finite-size hard-core interacting particles in two- or three-dimensional confined domains is considered in the limit that the confinement dimensions become comparable to the particle\\'s dimensions. The result is a nonlinear diffusion equation for the one-particle probability density function, with an overall collective diffusion that depends on both the excluded-volume and the narrow confinement. By including both these effects, the equation is able to interpolate between severe confinement (for example, single-file diffusion) and unconfined diffusion. Numerical solutions of both the effective nonlinear diffusion equation and the stochastic particle system are presented and compared. As an application, the case of diffusion under a ratchet potential is considered, and the change in transport properties due to excluded-volume and confinement effects is examined. © 2013 Society for Mathematical Biology.

  11. Modest net autotrophy in the oligotrophic ocean (United States)

    Letscher, Robert T.; Moore, J. Keith


    The metabolic state of the oligotrophic subtropical ocean has long been debated. Net community production (NCP) represents the balance of autotrophic carbon fixation with heterotrophic respiration. Many in vitro NCP estimates based on oxygen incubation methods and the corresponding scaling relationships used to predict the ecosystem metabolic balance have suggested the ocean gyres to be net heterotrophic; however, all in situ NCP methods find net autotrophy. Reconciling net heterotrophy requires significant allochthonous inputs of organic carbon to the oligotrophic gyres to sustain a preponderance of respiration over in situ production. Here we use the first global ecosystem-ocean circulation model that contains representation of the three allochthonous carbon sources to the open ocean, to show that the five oligotrophic gyres exhibit modest net autotrophy throughout the seasonal cycle. Annually integrated rates of NCP vary in the range 1.5-2.2 mol O2 m-2 yr-1 across the five gyre systems; however, seasonal NCP rates are as low as 1 ± 0.5 mmol O2 m-2 d-1 for the North Atlantic. Volumetric NCP rates are heterotrophic below the 10% light level; however, they become net autotrophic when integrated over the euphotic zone. Observational uncertainties when measuring these modest autotrophic NCP rates as well as the metabolic diversity encountered across space and time complicate the scaling up of in vitro measurements to the ecosystem scale and may partially explain the previous reports of net heterotrophy. The oligotrophic ocean is autotrophic at present; however, it could shift toward seasonal heterotrophy in the future as rising temperatures stimulate respiration.

  12. Confined zone dispersion flue gas desulfurization demonstration

    Energy Technology Data Exchange (ETDEWEB)


    The confined zone dispersion (CZD) process involves flue gas post-treatment, physically located between a boiler's outlet and its particulate collector, which in the majority of cases is an electrostatic precipitator. The features that distinguish this process from other similar injection processes are: Injection of an alkaline slurry directly into the duct, instead of injection of dry solids into the duct ahead of a fabric filter. Use of an ultrafine calcium/magnesium hydroxide, type S pressure-hydrated dolomitic lime. This commercial product is made from plentiful, naturally occurring dolomite. Low residence time, made possible by the high effective surface area of the Type S lime. Localized dispersion of the reagent. Slurry droplets contact only part of the gas while the droplets are drying, to remove up to 50 percent of the S0{sub 2} and significant amounts of NO{sub x}. The process uses dual fluid rather than rotary atomizers. Improved electrostatic precipitator performance via gas conditioning from the increased water vapor content, and lower temperatures. Supplemental conditioning with S0{sub 3} is not believed necessary for satisfactory removal of particulate matter.

  13. Diagnostics for magnetic confinement fusion research (United States)

    Weller, Arthur


    Significant progress towards the development of an attractive fusion energy source based on magnetic or inertial plasma confinement has been achieved within the international fusion energy program. High-level diagnostics capabilities are required to characterize fusion plasmas and to achieve a sound physics basis to design a fusion power plant. A large variety of different measuring techniques is used, most of them based on the detection of electromagnetic radiation in a wide range of wavelengths or of particles emitted from the plasma. Active probing by laser and particle beams permits to measure local plasma parameters directly, whereas passive measurements and imaging methods require unfolding and tomographic reconstruction techniques in order to obtain the spatial source distribution. Most diagnostics systems are limited in the accessible parameter range, in accuracy, temporal and spatial resolution, energy resolution and hardiness in a harsh environment, so that redundancy and complementarity of different methods is desirable. A considerable synergy exists between plasma diagnostics for fusion and astrophysics research. In particular, novel imaging detectors developed for the observation of astrophysical objects may be applied to fusion devices, too. An overview of diagnostics requirements, measuring techniques and selected results are presented with an emphasis of imaging diagnostics in toroidal magnetic fusion devices.

  14. Confinement Studies in High Temperature Spheromak Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D N; Mclean, H S; Wood, R D; Casper, T A; Cohen, B I; Hooper, E B; LoDestro, L L; Pearlstein, L D; Romero-Talamas, C


    Recent results from the SSPX spheromak experiment demonstrate the potential for obtaining good energy confinement (Te > 350eV and radial electron thermal diffusivity comparable to tokamak L-mode values) in a completely self-organized toroidal plasma. A strong decrease in thermal conductivity with temperature is observed and at the highest temperatures, transport is well below that expected from the Rechester-Rosenbluth model. Addition of a new capacitor bank has produced 60% higher magnetic fields and almost tripled the pulse length to 11ms. For plasmas with T{sub e} > 300eV, it becomes feasible to use modest (1.8MW) neutral beam injection (NBI) heating to significantly change the power balance in the core plasma, making it an effective tool for improving transport analysis. We are now developing detailed designs for adding NBI to SSPX and have developed a new module for the CORSICA transport code to compute the correct fast-ion orbits in SSPX so that we can simulate the effect of adding NBI; initial results predict that such heating can raise the electron temperature and total plasma pressure in the core by a factor of two.

  15. Human Adaptation to Isolated and Confined Environments (United States)

    Evans, Gary W.; Stokols, Daniel; Carrere, Sybil


    A study was conducted over seven months in a winter Antarctic isolated and confined environment (ICE). Physiological and psychological data was collected several times a week. Information was collected on a monthly basis on behavior and the use of physical facilities. Adaptation and information indicated that there was a significant decrease in epinephrine and norepinephrine during the middle trimester of the winter. No vital changes were found for blood pressure. Self reports of hostility and anxiety show a linear increase. There were no significant changes in depression during ICE. The physiological and psychological data do not move in a synchronous fashion over time. The data also suggest that both ambient qualities of an ICE and discrete social environmental events, such as the arrival of the summer crew, have an impact on the outcome measures used. It may be most appropiate to develop a model for ICE's that incorporates not only global chronic stressors common to all ICE's but also the role of discrete environmental effects which can minimize or enhance the influence of more chronic stressors. Behavioral adjustment information highlight the importance of developing schedules which balance work and recreational activities.

  16. Optical properties of matrix confined species (United States)

    Lezhnina, M. M.; Kynast, U. H.


    A majority of optically functional materials can be perceived as a liaison between ionic or molecular guests and a more or less rigid host. The guests exhibit an optical function, whereas the host provides suitable space, both of them synergistically complementing each other. The embracement of guests and hosts is often very intimate, as e.g. in typical phosphors, where luminescent ions even become part of the host. While the host-guest terminology usually is not applied to such marriages, the term becomes appropriate, if the host grants some degrees of spatial freedom, yet giving order and structure to its guests. Zeolites, clays and inverse opals are porous materials naturally providing hospitable cavities, channels or other compartments, and at the same time the guests are often demanded to occupy preassigned positions within these, or to structurally adapt to the interior host topology. Whereas zeolites and clays are merely patient providers of guest space, inverse opals, can actively turn the light on and off. The present article summarises and highlights recent experimental evidence, ongoing research and some envisaged merits resulting from the interaction of matrix confined luminescent ions, complexes and molecules with a focus on the optical properties of rare earth based materials.

  17. Thermalization in a holographic confining gauge theory

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Takaaki [Crete Center for Theoretical Physics, Department of Physics, University of Crete,71003 Heraklion (Greece); Kiritsis, Elias [Crete Center for Theoretical Physics, Department of Physics, University of Crete,71003 Heraklion (Greece); APC, University Paris Diderot, Sorbonne Paris Cité, UMR 7164 CNRS,10, rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13 (France); Rosen, Christopher [Crete Center for Theoretical Physics, Department of Physics, University of Crete,71003 Heraklion (Greece)


    Time dependent perturbations of states in the holographic dual of a 3+1 dimensional confining theory are considered. The perturbations are induced by varying the coupling to the theory’s most relevant operator. The dual gravitational theory belongs to a class of Einstein-dilaton theories which exhibit a mass gap at zero temperature and a first order deconfining phase transition at finite temperature. The perturbation is realized in various thermal bulk solutions by specifying time dependent boundary conditions on the scalar, and we solve the fully backreacted Einstein-dilaton equations of motion subject to these boundary conditions. We compute the characteristic time scale of many thermalization processes, noting that in every case we examine, this time scale is determined by the imaginary part of the lowest lying quasi-normal mode of the final state black brane. We quantify the dependence of this final state on parameters of the quench, and construct a dynamical phase diagram. Further support for a universal scaling regime in the abrupt quench limit is provided.

  18. Fuzzy Dark Matter from Infrared Confining Dynamics (United States)

    Davoudiasl, Hooman; Murphy, Christopher W.


    A very light boson of mass O (10-22) eV may potentially be a viable dark matter (DM) candidate, which can avoid phenomenological problems associated with cold DM. Such "fuzzy DM (FDM)" may naturally be an axion with a decay constant fa˜1 016- 1 018 GeV and a mass ma˜μ2/fa with μ ˜1 02 eV . Here, we propose a concrete model, where μ arises as a dynamical scale from infrared confining dynamics, analogous to QCD. Our model is an alternative to the usual approach of generating μ through string theoretic instanton effects. We outline the features of this scenario that result from various cosmological constraints. We find that those constraints are suggestive of a period of mild of inflation, perhaps from a strong first order phase transition, that reheats the standard model (SM) sector only. A typical prediction of our scenario, broadly speaking, is a larger effective number of neutrinos compared to the SM value Neff≈3 , as inferred from precision measurements of the cosmic microwave background. Some of the new degrees of freedom may be identified as "sterile neutrinos," which may be required to explain certain neutrino oscillation anomalies. Hence, aspects of our scenario could be testable in terrestrial experiments, which is a novelty of our FDM model.

  19. Confined nanoparticle measurement using Bessel Beam Microscopy (United States)

    Chakraborty, Chumki; Snoeyink, Craig


    With the advent of Lab-on-chip technologies, study of near surface phenomenon has gained a lot of importance due to their huge impact on bulk fluid properties. Such studies demand imaging techniques with utmost precision to capture the intricate details of the interface. But, resolution for most of the optical imaging systems is limited due to the light spreading effects of diffraction. This diffraction limited resolution, can be improved by the use of Bessel Beam microscopy. Bessel beam imaging technique when combined with a TIRF (Total Internal Reflection Fluorescence) system can be used for high resolution particle tracking experiments, to reveal detailed information about near surface particle positions and motions with their velocity profile and distribution. With the experimental set up combining these two powerful tools, we plan to present our particle tracking velocimetry results in the interface regime of confined nanoparticles in a binary fluid mixture. Such a study can contribute towards a better understanding of near surface fluid-particle interfaces.

  20. Electrostatically confined trilayer graphene quantum dots (United States)

    Mirzakhani, M.; Zarenia, M.; Vasilopoulos, P.; Peeters, F. M.


    Electrically gating of trilayer graphene (TLG) opens a band gap offering the possibility to electrically engineer TLG quantum dots. We study the energy levels of such quantum dots and investigate their dependence on a perpendicular magnetic field B and different types of stacking of the graphene layers. The dots are modeled as circular and confined by a truncated parabolic potential which can be realized by nanostructured gates or position-dependent doping. The energy spectra exhibit the intervalley symmetry EKe(m ) =-EK'h(m ) for the electron (e ) and hole (h ) states, where m is the angular momentum quantum number and K and K ' label the two valleys. The electron and hole spectra for B =0 are twofold degenerate due to the intervalley symmetry EK(m ) =EK'[-(m +1 ) ] . For both ABC [α =1.5 (1.2) for large (small) R ] and ABA (α =1 ) stackings, the lowest-energy levels show approximately a R-α dependence on the dot radius R in contrast with the 1 /R3 one for ABC-stacked dots with infinite-mass boundary. As functions of the field B , the oscillator strengths for dipole-allowed transitions differ drastically for the two types of stackings.

  1. Nano-confinement-driven enhanced magnetic relaxivity of SPIONs for targeted tumor bioimaging. (United States)

    Nguyen, Tuyen Duong Thanh; Pitchaimani, Arunkumar; Ferrel, Colin; Thakkar, Ravindra; Aryal, Santosh


    Superparamagnetic iron oxide nanoparticles (SPIONs) are highly biocompatible and have a versatile synthetic technique based on coprecipitation, reduction-precipitation, and hydrothermal methods, where Fe3+ and Fe2+ react in aqueous solutions; both these ions are present in our body and have clear metabolic pathways; therefore, they have attracted extensive research interest and development in the field of diagnostic imaging and therapy. However, most SPION-based clinical diagnostic contrast agents are discontinued due to severe pain, low transverse magnetic relaxivity range of 80-180 mM-1 s-1, shorter circulation half-life, and lack of disease specificity. Therefore, in this study, we engineered a bone cancer-targeted hybrid nanoconstruct (HNC) with a high transverse magnetic relaxivity of 625 mM-1 s-1, which was significantly higher than that of clinical contrast agents. The engineered HNC is peripherally decorated with a bone-seeking agent, alendronic acid-conjugated phospholipid, exhibiting a hydrodynamic size of 80 nm with a negative surface potential, -35 mV. The interior skeleton of the HNC is composed of biodegradable and biocompatible poly(l-lactic-co-glycolic acid) (PLGA), in which 5 nm SPIONs are confined. We have successfully tuned the distance between the confined SPIONs from 0.5 to 4 nm, as revealed by transmission electron microscopy (TEM) images and magnetic resonance image (MRI) phantoms. This cluster confinement dramatically enhances magnetic relaxivity possibly due to the increase in net local magnetization due to proximal field inhomogeneity. In an in vitro examination, 80% of HNC is found to bind with hydroxyapatite (HAp), which when characterized by TEM shows a painting of SPIONs over a HAp crystal. HNC is found to accumulate in mouse osteosarcoma tumor (K7M2 tumor model); both MRI and histological examination of the tumor show the potential of HNC as targeting agents for diagnosis of tumor in the bone.


    Directory of Open Access Journals (Sweden)

    Marília Matos Pereira Lopes


    Full Text Available The objective of this assignment was to identify if the University Net of Popular Cooperatives Technological Incubators (PCTIs Net is a social net. The research was an exploratory nature study with descriptive character, the technical procedure of the present research was the case study. The questionnaire was applied in 82% of the incubators belonging to the PCTIs Net, and interviews. The information acquired through the questionnaire was gathered and tabulated to compose the characterization of the net incubators and the social analyzer. With the Pajek program was created the social analyzer and the centralizing box. Was performed to compare the results with previous work Rennó et al. (2010 proposed that the same goal using a different approach. Ending the analysis guided by the characteristics of a social net, it was observed that the PCTIs Net is a social net, however it was emphasized that the existing communication is a point where the net needs to be fortified.

  3. Activation of PAD4 in NET formation

    Directory of Open Access Journals (Sweden)

    Amanda eRohrbach


    Full Text Available Peptidyl arginine deiminases, or PADs, convert arginine residues to the non-ribosomally encoded amino acid citrulline in a variety of protein substrates. PAD4 is expressed in granulocytes and is essential for the formation of neutrophil extracellular traps (NETs via PAD4-mediated histone citrullination. Citrullination of histones is thought to promote NET formation by inducing chromatin decondensation and facilitating the expulsion of chromosomal DNA that is coated with antimicrobial molecules. Numerous stimuli have been reported to lead to PAD4 activation and NET formation. However, how this signaling process proceeds and how PAD4 becomes activated in cells is largely unknown. Herein, we describe the various stimuli and signaling pathways that have been implicated in PAD4 activation and NET formation, including the role of reactive oxygen species generation. To provide a foundation for the above discussion, we first describe PAD4 structure and function, and how these studies led to the development of PAD-specific inhibitors. A comprehensive survey of the receptors and signaling pathways that regulate PAD4 activation will be important for our understanding of innate immunity, and the identification of signaling intermediates in PAD4 activation may also lead to the generation of pharmaceuticals to target NET-related pathogenesis.

  4. The net charge at interfaces between insulators (United States)

    Bristowe, N. C.; Littlewood, P. B.; Artacho, Emilio


    The issue of the net charge at insulating oxide interfaces is briefly reviewed with the ambition of dispelling myths of such charges being affected by covalency and related charge density effects. For electrostatic analysis purposes, the net charge at such interfaces is defined by the counting of discrete electrons and core ion charges, and by the definition of the reference polarization of the separate, unperturbed bulk materials. The arguments are illustrated for the case of a thin film of LaAlO3 over SrTiO3 in the absence of free carriers, for which the net charge is exactly 0.5e per interface formula unit, if the polarization response in both materials is referred to zero bulk values. Further consequences of the argument are extracted for structural and chemical alterations of such interfaces, in which internal rearrangements are distinguished from extrinsic alterations (changes of stoichiometry, redox processes), only the latter affecting the interfacial net charge. The arguments are reviewed alongside the proposal of Stengel and Vanderbilt (2009 Phys. Rev. B 80 241103) of using formal polarization values instead of net interfacial charges, based on the interface theorem of Vanderbilt and King-Smith (1993 Phys. Rev. B 48 4442-55). Implications for non-centrosymmetric materials are discussed, as well as for interfaces for which the charge mismatch is an integer number of polarization quanta.

  5. Automating Ontological Annotation with WordNet

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Tratz, Stephen C.; Gregory, Michelle L.; Chappell, Alan R.; Whitney, Paul D.; Posse, Christian; Paulson, Patrick R.; Baddeley, Bob L.; Hohimer, Ryan E.; White, Amanda M.


    Semantic Web applications require robust and accurate annotation tools that are capable of automating the assignment of ontological classes to words in naturally occurring text (ontological annotation). Most current ontologies do not include rich lexical databases and are therefore not easily integrated with word sense disambiguation algorithms that are needed to automate ontological annotation. WordNet provides a potentially ideal solution to this problem as it offers a highly structured lexical conceptual representation that has been extensively used to develop word sense disambiguation algorithms. However, WordNet has not been designed as an ontology, and while it can be easily turned into one, the result of doing this would present users with serious practical limitations due to the great number of concepts (synonym sets) it contains. Moreover, mapping WordNet to an existing ontology may be difficult and requires substantial labor. We propose to overcome these limitations by developing an analytical platform that (1) provides a WordNet-based ontology offering a manageable and yet comprehensive set of concept classes, (2) leverages the lexical richness of WordNet to give an extensive characterization of concept class in terms of lexical instances, and (3) integrates a class recognition algorithm that automates the assignment of concept classes to words in naturally occurring text. The ensuing framework makes available an ontological annotation platform that can be effectively integrated with intelligence analysis systems to facilitate evidence marshaling and sustain the creation and validation of inference models.

  6. Ontological Annotation with WordNet

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Tratz, Stephen C.; Gregory, Michelle L.; Chappell, Alan R.; Whitney, Paul D.; Posse, Christian; Paulson, Patrick R.; Baddeley, Bob; Hohimer, Ryan E.; White, Amanda M.


    Semantic Web applications require robust and accurate annotation tools that are capable of automating the assignment of ontological classes to words in naturally occurring text (ontological annotation). Most current ontologies do not include rich lexical databases and are therefore not easily integrated with word sense disambiguation algorithms that are needed to automate ontological annotation. WordNet provides a potentially ideal solution to this problem as it offers a highly structured lexical conceptual representation that has been extensively used to develop word sense disambiguation algorithms. However, WordNet has not been designed as an ontology, and while it can be easily turned into one, the result of doing this would present users with serious practical limitations due to the great number of concepts (synonym sets) it contains. Moreover, mapping WordNet to an existing ontology may be difficult and requires substantial labor. We propose to overcome these limitations by developing an analytical platform that (1) provides a WordNet-based ontology offering a manageable and yet comprehensive set of concept classes, (2) leverages the lexical richness of WordNet to give an extensive characterization of concept class in terms of lexical instances, and (3) integrates a class recognition algorithm that automates the assignment of concept classes to words in naturally occurring text. The ensuing framework makes available an ontological annotation platform that can be effectively integrated with intelligence analysis systems to facilitate evidence marshaling and sustain the creation and validation of inference models.

  7. Development of net cage acoustic alarm system (United States)

    Hong, Shih-Wei; Wei, Ruey-Chang


    In recent years, the fishery production has been drastically decreased in Taiwan, mainly due to overfishing and coast pollution; therefore, fishermen and corporations are encouraged by government to invest in ocean net cage aquaculture. However, the high-price fishes in the net cage are often coveted, so incidences of fish stealing and net cage breaking were found occasionally, which cause great economical loss. Security guards or a visual monitoring system has limited effect, especially in the night when these intrusions occur. This study is based on acoustic measure to build a net cage alarm system, which includes the sonobuoy and monitor station on land. The sonobuoy is a passive sonar that collects the sounds near the net cage and transmits the suspected signal to the monitor station. The signals are analyzed by the control program on the personal computer in the monitor station, and the alarms at different stages could be activated by the sound levels and durations of the analyzed data. To insure long hours of surveillance, a solar panel is applied to charge the battery, and a photodetector is used to activate the system.

  8. The NeuroDevNet vision. (United States)

    Goldowitz, Dan; McArthur, Dawn


    The NeuroDevNet Network of Centres of Excellence has created the first trans-Canada effort devoted to the study of brain development from basic to clinical to societal perspectives. NeuroDevNet's vision is to accelerate efforts to (i) understand normal brain development; (ii) enhance our ability to make diagnoses of when normal development goes awry; and (iii) develop interventions to improve or prevent neurodevelopmental disorders. An early diagnosis coupled with the right therapies, The NeuroDevNet Network of Centres of Excellence has created the first trans-Canada effort devoted to the study of brain development from basic to clinical to societal perspectives. NeuroDevNet's vision is to accelerate efforts to (i) understand normal brain development; (ii) enhance our ability to make diagnoses of when normal development goes awry; and (iii) develop interventions to improve or prevent neurodevelopmental disorders. An early diagnosis coupled with the right therapies, Demonstration Projects. Funds were also allocated for an Opportunities Initiative. There is a wide of expertise amongst NeuroDevNet members. Researchers are supported by the management centre, three Platforms (Imaging; Genetics/ Epigenetics; Animal Models) and three Cores (Neuroethics; Neuroinformatics; Knowledge Translation). We emphasize multidisciplinary training of young researchers to advance the understanding of brain disorders that affect children. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. The net charge at interfaces between insulators

    Energy Technology Data Exchange (ETDEWEB)

    Bristowe, N C; Littlewood, P B [Theory of Condensed Matter Group, Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Artacho, Emilio, E-mail: [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ (United Kingdom)


    The issue of the net charge at insulating oxide interfaces is briefly reviewed with the ambition of dispelling myths of such charges being affected by covalency and related charge density effects. For electrostatic analysis purposes, the net charge at such interfaces is defined by the counting of discrete electrons and core ion charges, and by the definition of the reference polarization of the separate, unperturbed bulk materials. The arguments are illustrated for the case of a thin film of LaAlO{sub 3} over SrTiO{sub 3} in the absence of free carriers, for which the net charge is exactly 0.5e per interface formula unit, if the polarization response in both materials is referred to zero bulk values. Further consequences of the argument are extracted for structural and chemical alterations of such interfaces, in which internal rearrangements are distinguished from extrinsic alterations (changes of stoichiometry, redox processes), only the latter affecting the interfacial net charge. The arguments are reviewed alongside the proposal of Stengel and Vanderbilt (2009 Phys. Rev. B 80 241103) of using formal polarization values instead of net interfacial charges, based on the interface theorem of Vanderbilt and King-Smith (1993 Phys. Rev. B 48 4442-55). Implications for non-centrosymmetric materials are discussed, as well as for interfaces for which the charge mismatch is an integer number of polarization quanta. (viewpoint)

  10. Association mapping utilizing diverse barley lines reveals net form net blotch seedling resistance/susceptibility loci (United States)

    Pyrenophora teres f. teres is a necrotrophic fungal pathogen and the causal agent of the economically important foliar disease net form net blotch (NFNB) of barley. The deployment of effective and durable resistance against P. teres f. teres has been hindered by the complexity of quantitative resist...

  11. Towards Self-Managed Executable Petri Nets

    DEFF Research Database (Denmark)

    Hansen, Klaus Marius; Zhang, Weishan; Ingstrup, Mads


    An issue in self-managed systems is that different abstractions and programming models are used on different architectural layers, leading to systems that are harder to build and understand. To alleviate this, we introduce a self-management approach which combines high-level Petri nets...... with the capability of distributed communication among nets. Organized in a three-layer goal management, change management, and component control architecture this allows for self-management in distributed systems. We validate the approach through the Flamenco/CPN middleware that allows for self-management of service......-oriented pervasive computing systems through the runtime interpretation of colored Petri nets. The current work focuses on the change management and component control layers....

  12. Professional ASP.NET MVC 2

    CERN Document Server

    Galloway, Jon; Haack, Phil


    Top-selling MVC book from a top team at Microsoft—now fully updated!. ASP.NET MVC 2.0 is now available and shipping with Visual Studio 2010 and .NET 4. A new update to Microsoft's Model-View-Controller technologies, MVC 2.0 enables developers to build dynamic, data-driven Web sites. This in-depth book shows you step-by-step how to use MVC 2.0. You'll learn both the theory behind MVC 2.0, as well as walk through practical tutorials, where you'll create a real-world application. Topics include transitioning from ASP.NET development, as well as an overview of related tools and technologies, inclu

  13. .net core application lifecycle on Openshift

    CERN Multimedia

    CERN. Geneva


    # .net core application lifecycle on Openshift I will show an example of a lifecycle of an OpenShift application with an emphasis on the continuous integration and deployment. The application compatible with [.net Standard]( can be easily deployed on OpenShift using [Source2Image]( functionality, which doesn't require developers to maintain docker images of the application. I will also present how to efficiently integrate this feature into GitLab pipelines with an automated deployment of the "review" environment, as one its parts.

  14. Application and Theory of Petri Nets

    DEFF Research Database (Denmark)

    This volume contains the proceedings of the 13th International Conference onApplication and Theory of Petri Nets, held in Sheffield, England, in June 1992. The aim of the Petri net conferences is to create a forum for discussing progress in the application and theory of Petri nets. Typically......, the conferences have 150-200 participants, one third of these coming from industry and the rest from universities and research institutions. The 1992 conference was organized by the School of Computing and Management Sciences at Sheffield City Polytechnic, England. The volume contains twoinvited papers, by G....... Balbo and W. Reisig, 18 submitted papers, and seven project papers. The submitted papers and project presentations were selectedby the programme committee and a panel of referees from a large number of submissions....

  15. Chapter 17: Estimating Net Savings: Common Practices

    Energy Technology Data Exchange (ETDEWEB)

    Violette, D. M.; Rathbun, P.


    This chapter focuses on the methods used to estimate net energy savings in evaluation, measurement, and verification (EM&V) studies for energy efficiency (EE) programs. The chapter provides a definition of net savings, which remains an unsettled topic both within the EE evaluation community and across the broader public policy evaluation community, particularly in the context of attribution of savings to particular program. The chapter differs from the measure-specific Uniform Methods Project (UMP) chapters in both its approach and work product. Unlike other UMP resources that provide recommended protocols for determining gross energy savings, this chapter describes and compares the current industry practices for determining net energy savings, but does not prescribe particular methods.

  16. Acoustic Focusing and Energy Confinement Based on Multilateral Metasurfaces (United States)

    Qi, Shuibao; Li, Yong; Assouar, Badreddine


    Metamaterial-based acoustic wave manipulation shows great potential in effective acoustic energy confinement and low-frequency acoustic isolation. We numerically and theoretically propose here a concept based on multilateral metasurfaces for reflected acoustic focusing and energy confinement. The theoretical phase-shift profile required for reflected wave focusing and governed by the generalized Snell's law can be discretely realized by appropriately arraying the labyrinthine units in the right sequences. Based on this design, multilateral metasurfaces for acoustic wave focusing and energy confinement under point-source incidence are considered and sufficiently investigated. The coupling effects and multiple reflections between or among metasurfaces, which play a significant role in the energy confinement, are initially analyzed and discussed. We show that the acoustic focusing and confinement increase with the sides of the multilateral metasurfaces as anticipated. In addition to the contribution of the first reflection, multiple reflections also contribute to the acoustic focusing and energy confinement, especially when the metasurfaces are configured in parallel. The proposed multilateral metasurfaces should have excellent performance in acoustic energy confinement in various situations due to the variable designs and strong acoustic focusing capabilities.

  17. Reynolds stress and shear flow generation

    DEFF Research Database (Denmark)

    Korsholm, Søren Bang; Michelsen, Poul; Naulin, V.


    to the treatment of the pseudo-Reynolds stress, we present analytical and numerical results which demonstrate that the Reynolds stress in a plasma, indeed, generates a poloidal shear flow. The numerical simulations are performed both in a drift wave turbulence regime and a resistive interchange turbulence regime......The so-called Reynolds stress may give a measure of the self-consistent flow generation in turbulent fluids and plasmas by the small-scale turbulent fluctuations. A measurement of the Reynolds stress can thus help to predict flows, e.g. shear flows in plasmas. This may assist the understanding...... of improved confinement scenarios such as H-mode confinement regimes. However, the determination of the Reynolds stress requires measurements of the plasma potential, a task that is difficult in general and nearly impossible in hot plasmas in large devices. In this work we investigate an alternative method...

  18. The transition from No Net Loss to a Net Gain of biodiversity is far from trivial

    DEFF Research Database (Denmark)

    Bull, Joseph William; Brownlie, S.


    The objectives of No Net Loss and Net Gain have emerged as key principles in conservation policy. Both give rise to mechanisms by which certain unavoidable biodiversity losses associated with development are quantified, and compensated with comparable gains (e.g. habitat restoration). The former...... seeks a neutral outcome for biodiversity after losses and gains are accounted for, and the latter seeks an improved outcome. Policy-makers often assume that the transition from one to the other is straightforward and essentially a question of the amount of compensation provided. Consequently, companies...... increasingly favour Net Gain type commitments, and financial institutions make lending conditional on either objective, depending on the habitat involved. We contend, however, that achieving Net Gain is fundamentally different to achieving No Net Loss, and moving from one to the other is less trivial than...

  19. Pattern formation in confined chemical gardens (United States)

    De Wit, Anne; Haudin, Florence; Brau, Fabian; Cartwright, Julyan


    Chemical gardens are plant-like mineral structures first described in the seventeenth century and popularly known from chemistry sets for children. They are classically grown in three-dimensional containers by placing a solid metal-salt seed into a silicate solution. When the metal salt starts dissolving in the silicate solution, a semi-permeable membrane forms by precipitation across which water is pumped by osmosis from the silicate solution into the metal salt solution, further dissolving the salt. Above a given pressure, the membrane breaks. The dissolved metal salt solution being generally less dense than the reservoir silicate solution, it rises as a buoyant jet through the broken membrane and further precipitates in contact with the silicate solution, producing a collection of mineral forms that resemble a garden. Such gardens are the subject of increased interest as a model system to understand pattern formation in sea-ice brinicles and hydrothermal vents on the seafloor, among others. All these self-organized precipitation structures at the interface between chemistry, fluid dynamics and mechanics share indeed common chemical, mechanical and electrical properties. In this framework, we study experimentally spatial patterns resulting from the growth of chemical gardens in confined quasi-two-dimensional (2D) geometries upon radial injection of a metallic salt solution into a silicate solution in a horizontal Hele-Shaw cell. We find a large variety of patterns including spirals, fingers, worms, filiform tubes, and flower-like patterns. By exploring the phase space of reactant concentrations and injection flow rates, we observe transitions between these spatio-temporal structures resulting from a coupling between the precipitation reaction, mechanical effects and hydrodynamic instabilities.

  20. Engineered barriers for radioactive waste confinement

    Directory of Open Access Journals (Sweden)

    Fernández, R.


    Full Text Available Nuclear power plants generate long-lived radioactive waste of high toxicity. The security assessment of repositories destined to definitive confinement of radioactive waste has been studied for several decades. Deep geological repositories are technically feasible and begin to be built by some pioneer countries. The scientific evaluation of interactions between the different engineered barriers is studied by laboratory experiments, natural analogues and modeling studies. The three methods are able to represent and validate the main geochemical processes that take place in the near field. This paper reviews the scientific and technical basis of the concept of geological disposal, with particular focus on the methods of study applied to the evaluation of geochemical stability of the bentonite barrier.

    Las centrales nucleares generan residuos radiactivos de elevada peligrosidad y permanencia en el tiempo. La evaluación de la seguridad de repositorios destinados al alojamiento definitivo de estos residuos lleva estudiándose desde hace varias décadas. El almacenamiento geológico es técnicamente factible y empieza ya a desarrollarse en países pioneros. La evaluación científica de las interacciones entre las distintas barreras de ingeniería se estudia mediante ensayos de laboratorio, análisis de análogos naturales y modelos teóricos. Las tres vías de estudio son capaces de representar y validar los principales procesos geoquímicos que tienen lugar en el campo cercano al repositorio. Este artículo revisa los fundamentos científicos y técnicos del concepto de almacenamiento geológico detallando, en particular, los métodos de estudio aplicados a la evaluación de la estabilidad geoquímica de la barrera de bentonita.

  1. Definition of Ignition in Inertial Confinement Fusion (United States)

    Christopherson, A. R.; Betti, R.


    Defining ignition in inertial confinement fusion (ICF) is an unresolved problem. In ICF, a distinction must be made between the ignition of the hot spot and the propagation of the burn wave in the surrounding dense fuel. Burn propagation requires that the hot spot is robustly ignited and the dense shell exhibits enough areal density. Since most of the energy gain comes from burning the dense shell, in a scale of increasing yields, hot-spot ignition comes before high gains. Identifying this transition from hot-spot ignition to burn-wave propagation is key to defining ignition in general terms applicable to all fusion approaches that use solid DT fuel. Ad hoc definitions such as gain = 1 or doubling the temperature are not generally valid. In this work, we show that it is possible to identify the onset of ignition through a unique value of the yield amplification defined as the ratio of the fusion yield including alpha-particle deposition to the fusion yield without alphas. Since the yield amplification is a function of the fractional alpha energy fα =EαEα 2Ehs 2Ehs (a measurable quantity), it appears possible not only to define ignition but also to measure the onset of ignition by the experimental inference of the fractional alpha energy and yield amplification. This material is based upon work supported by the Department of Energy Office of Fusion Energy Services under Award Number DE-FC02-04ER54789 and National Nuclear Security Administration under Award Number DE-NA0001944.

  2. Effect of confining pressure due to external jacket of steel plate or shape memory alloy wire on bond behavior between concrete and steel reinforcing bars. (United States)

    Choi, Eunsoo; Kim, Dongkyun; Park, Kyoungsoo


    For external jackets of reinforced concrete columns, shape memory alloy (SMA) wires are easy to install, and they provide active and passive confining pressure; steel plates, on the other hand, only provide passive confining pressure, and their installation on concrete is not convenient because of the requirement of a special device. To investigate how SMA wires distinctly impact bond behavior compared with steel plates, this study conducted push-out bond tests of steel reinforcing bars embedded in concrete confined by SMA wires or steel plates. For this purpose, concrete cylinders were prepared with dimensions of 100 mm x 200 mm, and D-22 reinforcing bars were embedded at the center of the concrete cylinders. External jackets of 1.0 mm and 1.5 mm thickness steel plates were used to wrap the concrete cylinders. Additionally, NiTiNb SMA wire with a diameter of 1.0 mm was wound around the concrete cylinders. Slip of the reinforcing bars due to pushing force was measured by using a displacement transducer, while the circumferential deformation of specimens was obtained by using an extensometer. The circumferential deformation was used to calculate the circumferential strains of the specimens. This study assessed the radial confining pressure due to the external jackets on the reinforcing bars at bond strength from bond stress-slip curves and bond stress-circumferential strain curves. Then, the effects of the radial confining pressure on the bond behavior of concrete are investigated, and an equation is suggested to estimate bond strength using the radial confining pressure. Finally, this study focused on how active confining pressure due to recovery stress of the SMA wires influences bond behavior.

  3. Confinement vs. isolation as analogue environments for Mars missions from a human ethology viewpoint. (United States)

    Tafforin, Carole


    This study compares observational data from two situations designed as planetary exploration missions: the Tara expedition and the Mars-500 experiment. We examined the issue of distinct environmental factors, isolation vs. confinement, which may have different or similar impacts on crews' behavioral manifestations for long-term adaptation, such as on a Mars mission. The Tara expedition was a 507-d polar drift of the Tara schooner embedded in the Arctic ice with two successive periods of summer and winter-over in an isolated environment. The Mars-500 experiment took place in Moscow and was a 520-d simulation of a trip to Mars, the Mars landing, and the return trip to Earth in a confined environment. We used the ethological method based on observation, description, and quantification of individual and interindividual behaviors. These events were scored from video recordings made during daily life activities and aggregated according to the summer period and to the outgoing trip for the whole crew (N = 6) for each situation, respectively. We did not observe differences in the frequency of facial expressions and in the duration of body interactions. Conversely, there were differences in the frequency of collateral acts and in the duration of personal actions with the highest levels during the Mars-500 experiment (0.52 /min and 41,799 s); the highest level of visual interactions was observed during the Tara expedition (33,167 s). We found that confinement generates stress manifestations vs. isolation, that isolation enhances social relashionships vs. confinement, and that the crew adapted positively to both environments.

  4. APIs de seguridad en .NET Framework


    Domínguez Ruiz, Abel


    Este trabajo hace un estudio de algunas de las herramientas de seguridad disponibles en .Net Framework así como la forma de usarlas en un desarrollo web bajo la metodología de desarrollo de ASP.NET siguiendo el modelo Vista-Controlador y usando como entorno de desarrollo Visual Studio. Además de repasar las herramientas disponibles y la forma de uso se ha desarrollado también una aplicación de ejemplo: ItemCoteca-Web; en la que se demuestra cómo resolver el registro de usuarios, la autenticac...

  5. An ECNO semantics for Petri nets

    DEFF Research Database (Denmark)

    Kindler, Ekkart


    The Event Coordination Notation (ECNO) allows modelling the behaviour of software on top of structural software models - and to generate program code from these models fully automatically. ECNO distinguishes between the local behaviour of elements (objects) and the global behaviour, which denes t...... work. In this paper, we will show that the ECNO, in turn, can be used for modelling the behaviour of Petri nets in a simple and concise way. What is more, we will show that the ECNO semantics of Place/Transition Systems can easily be extended to so-called signal-event nets....

  6. Introducing NET 40 With Visual Studio 2010

    CERN Document Server

    Mackey, A


    Microsoft is introducing a large number of changes to the way that the .NET Framework operates. Familiar technologies are being altered, best practices replaced, and developer methodologies adjusted. Many developers find it hard to keep up with the pace of change across .NET's ever-widening array of technologies. You may know what's happening in C#, but how about the Azure cloud? How is that going to affect your work? What are the limitations of the new pLINQ syntax? What you need is a roadmap. A guide to help you see the innovations that matter and to give you a head start on the opportunitie

  7. Deep Belief Nets for Topic Modeling

    DEFF Research Database (Denmark)

    Maaløe, Lars; Arngren, Morten; Winther, Ole


    -formative. In this paper we describe large-scale content based collaborative filtering for digital publishing. To solve the digital publishing recommender problem we compare two approaches: latent Dirichlet allocation (LDA) and deep be-lief nets (DBN) that both find low-dimensional latent representations for documents....... Efficient retrieval can be carried out in the latent representation. We work both on public benchmarks and digital media content provided by Issuu, an on-line publishing platform. This article also comes with a newly developed deep belief nets toolbox for topic modeling tailored towards performance...

  8. Performance Analysis Using Coloured Petri Nets

    DEFF Research Database (Denmark)

    Wells, Lisa Marie


    This paper provides an overview of improved facilities for performance analysis using coloured Petri nets. Coloured Petri nets is a formal method that is well suited for modeling and analyzing large and complex systems. The paper describes steps that have been taken to make a distinction between...... modeling the behavior of a system and observing the behavior of a model. Performance-related facilities are discussed, including facilities for collecting data, running multiple simulations, generating statistically reliable simulation output, and comparing alternative system configurations....

  9. Net Gain: A New Method for Preventing Malaria Deaths | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    A finely spun net could prevent as many as one-third of all child deaths in Africa, reports IDRC's new publication, Net Gain. Studies conducted in Gambia, Ghana, and Kenya show that the insecticide-treated mosquito net reduced the mortality rate of children under 5 years of age by up to 63 percent. Net Gain reviews and ...

  10. Superfluid phases of $^3$He in a periodic confined geometry


    Wiman, J. J.; Sauls, J. A.


    Predictions and discoveries of new phases of superfluid $^3$He in confined geometries, as well as novel topological excitations confined to surfaces and edges of near a bounding surface of $^3$He, are driving the fields of superfluid $^3$He infused into porous media, as well as the fabrication of sub-micron to nano-scale devices for controlled studies of quantum fluids. In this report we consider superfluid $^3$He confined in a periodic geometry, specifically a two-dimensional lattice of squa...

  11. Scale testing of a partially confined blast chamber

    CSIR Research Space (South Africa)

    Grundling, W


    Full Text Available at the peak pressure readings from the confined and unconfined graphs, it is clear that in both cases the pressure has increased by partially confining the open side by 65%. Face-on pressure increased from 1 MPa up to 1.7 Mpa, while side-on pressure... readings increased from 0.8 MPa to 0.95 MPa in the confined state. It is recommended that more tests are done within the scaled blast chamber to retrieve repeatability in measurement results. Up-scaling of the pendulum to cover the full-size blast...

  12. Hard-wall confinement of a fractional quantum Hall liquid (United States)

    Macaluso, E.; Carusotto, I.


    We make use of numerical exact diagonalization calculations to explore the physics of ν =1 /2 bosonic fractional quantum Hall droplets in the presence of experimentally realistic cylindrically symmetric hard-wall potentials. This kind of confinement is found to produce very different many-body spectra compared to a harmonic trap or the so-called extremely steep limit. For a relatively weak confinement, the degeneracies are lifted and the low-lying excited states organize themselves in energy branches that can be explained in terms of their Jack polynomial representation. For a strong confinement, a strong spatial deformation of the droplet is found, with an unexpected depletion of its central density.

  13. Mars MetNet Mission Status (United States)

    Harri, Ari-Matti; Aleksashkin, Sergei; Arruego, Ignacio; Schmidt, Walter; Genzer, Maria; Vazquez, Luis; Haukka, Harri


    New kind of planetary exploration mission for Mars is under development in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission is based on a new semi-hard landing vehicle called MetNet Lander (MNL). The scientific payload of the Mars MetNet Precursor [1] mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide significant insights in to the Martian atmospheric behavior. The key technologies of the MetNet Lander have been qualified and the electrical qualification model (EQM) of the payload bay has been built and successfully tested. 1. MetNet Lander The MetNet landing vehicles are using an inflatable entry and descent system instead of rigid heat shields and parachutes as earlier semi-hard landing devices have used. This way the ratio of the payload mass to the overall mass is optimized. The landing impact will burrow the payload container into the Martian soil providing a more favorable thermal environment for the electronics and a suitable orientation of the telescopic boom with external sensors and the radio link antenna. It is planned to deploy several tens of MNLs on the Martian surface operating at least partly at the same time to allow meteorological network science. 2. Scientific Payload The payload of the two MNL precursor models includes the following instruments: Atmospheric instruments: 1. MetBaro Pressure device 2. MetHumi Humidity device 3. MetTemp Temperature sensors Optical devices: 1. PanCam Panoramic 2. MetSIS Solar irradiance sensor with OWLS optical wireless system for data transfer 3. DS Dust sensor The descent processes dynamic properties are monitored by a special 3-axis accelerometer combined with a 3-axis gyrometer. The data will be sent via auxiliary beacon antenna throughout the

  14. Markets, voucher subsidies and free nets combine to achieve high bed net coverage in rural Tanzania

    Directory of Open Access Journals (Sweden)

    Gerrets Rene PM


    Full Text Available Abstract Background Tanzania has a well-developed network of commercial ITN retailers. In 2004, the government introduced a voucher subsidy for pregnant women and, in mid 2005, helped distribute free nets to under-fives in small number of districts, including Rufiji on the southern coast, during a child health campaign. Contributions of these multiple insecticide-treated net delivery strategies existing at the same time and place to coverage in a poor rural community were assessed. Methods Cross-sectional household survey in 6,331 members of randomly selected 1,752 households of 31 rural villages of Demographic Surveillance System in Rufiji district, Southern Tanzania was conducted in 2006. A questionnaire was administered to every consenting respondent about net use, treatment status and delivery mechanism. Findings Net use was 62.7% overall, 87.2% amongst infants (0 to1 year, 81.8% amongst young children (>1 to 5 years, 54.5% amongst older children (6 to 15 years and 59.6% amongst adults (>15 years. 30.2% of all nets had been treated six months prior to interview. The biggest source of nets used by infants was purchase from the private sector with a voucher subsidy (41.8%. Half of nets used by young children (50.0% and over a third of those used by older children (37.2% were obtained free of charge through the vaccination campaign. The largest source of nets amongst the population overall was commercial purchase (45.1% use and was the primary means for protecting adults (60.2% use. All delivery mechanisms, especially sale of nets at full market price, under-served the poorest but no difference in equity was observed between voucher-subsidized and freely distributed nets. Conclusion All three delivery strategies enabled a poor rural community to achieve net coverage high enough to yield both personal and community level protection for the entire population. Each of them reached their relevant target group and free nets only temporarily

  15. Stress and stress counselling.


    Matheson, K. H.


    This is a report by the 1989 National Association of Clinical Tutors Wyeth Travelling Fellow to the United States of America. The stresses of postgraduate training and attempts to modify these are described, including stress counselling. The significance of stress and the relevance of the findings for postgraduate training in the United Kingdom are considered.

  16. The Nurse Entrance Test (NET): an early predictor of academic success. (United States)

    Abdur-Rahman, V; Femea, P L; Gaines, C


    The purpose of this study is to determine whether a relationship exists between beginning nursing students' Nurse Entrance Test (NET) scores and their academic success within the first year of professional study. The major goal is to identify predictors of academic success so that supportive academic strategies could be implemented for the at-risk student. A statistically significant relationship is found between NET reading comprehension, math and composite scores and nursing grades during the first semester. Test-taking skills, social stressors and learning styles were also significantly related to course performance. Successful students had significantly higher reading, math, and composite scores and lower family and social stress scores than unsuccessful students. NET scores were also predictive of nursing grades, accounting for 10-33% of the variance when entered into a multiple regression equation.

  17. Pneumatic fractures in confined granular media (United States)

    Eriksen, Fredrik K.; Toussaint, Renaud; Turquet, Antoine L.; Mâløy, Knut J.; Flekkøy, Eirik G.


    We perform experiments where air is injected at a constant overpressure Pin, ranging from 5 to 250 kPa, into a dry granular medium confined within a horizontal linear Hele-Shaw cell. The setup allows us to explore compacted configurations by preventing decompaction at the outer boundary, i.e., the cell outlet has a semipermeable filter such that beads are stopped while air can pass. We study the emerging patterns and dynamic growth of channels in the granular media due to fluid flow, by analyzing images captured with a high speed camera (1000 images/s). We identify four qualitatively different flow regimes, depending on the imposed overpressure, ranging from no channel formation for Pin below 10 kPa, to large thick channels formed by erosion and fingers merging for high Pin around 200 kPa. The flow regimes where channels form are characterized by typical finger thickness, final depth into the medium, and growth dynamics. The shape of the finger tips during growth is studied by looking at the finger width w as function of distance d from the tip. The tip profile is found to follow w (d ) ∝dβ , where β =0.68 is a typical value for all experiments, also over time. This indicates a singularity in the curvature d2d /d w2˜κ ˜d1 -2 β , but not of the slope d w /d d ˜dβ -1 , i.e., more rounded tips rather than pointy cusps, as they would be for the case β >1 . For increasing Pin, the channels generally grow faster and deeper into the medium. We show that the channel length along the flow direction has a linear growth with time initially, followed by a power-law decay of growth velocity with time as the channel approaches its final length. A closer look reveals that the initial growth velocity v0 is found to scale with injection pressure as v0∝Pin3/2 , while at a critical time tc there is a cross-over to the behavior v (t ) ∝t-α , where α is close to 2.5 for all experiments. Finally, we explore the fractal dimension of the fully developed patterns. For

  18. EVo: Net Shape RTM Production Line


    Sven Torstrick; Felix Kruse; Martin Wiedemann


    EVo research platform is operated by the Center for Lightweight-Production-Technology of the German Aerospace Center in Stade. Its objective is technology demonstration of a fully automated RTM (Resin Transfer Molding) production line for composite parts in large quantities. Process steps include cutting and ply handling, draping, stacking, hot-forming, preform-trimming to net shape, resin injection, curing and demolding.

  19. The Lotto and Expected Net Revenue


    Scoggins, John F.


    A multiperiod model (based on sales from the Florida Lotto) is used to estimate revenue and probability that the grand prize will roll over. Results indicate that allocating a greater percentage of ticket sales to the grand prize increases net revenue.

  20. Integrating phenotype ontologies with PhenomeNET

    KAUST Repository

    Rodriguez-Garcia, Miguel Angel


    Background Integration and analysis of phenotype data from humans and model organisms is a key challenge in building our understanding of normal biology and pathophysiology. However, the range of phenotypes and anatomical details being captured in clinical and model organism databases presents complex problems when attempting to match classes across species and across phenotypes as diverse as behaviour and neoplasia. We have previously developed PhenomeNET, a system for disease gene prioritization that includes as one of its components an ontology designed to integrate phenotype ontologies. While not applicable to matching arbitrary ontologies, PhenomeNET can be used to identify related phenotypes in different species, including human, mouse, zebrafish, nematode worm, fruit fly, and yeast. Results Here, we apply the PhenomeNET to identify related classes from two phenotype and two disease ontologies using automated reasoning. We demonstrate that we can identify a large number of mappings, some of which require automated reasoning and cannot easily be identified through lexical approaches alone. Combining automated reasoning with lexical matching further improves results in aligning ontologies. Conclusions PhenomeNET can be used to align and integrate phenotype ontologies. The results can be utilized for biomedical analyses in which phenomena observed in model organisms are used to identify causative genes and mutations underlying human disease.

  1. Soundness of Timed-Arc Workflow Nets

    DEFF Research Database (Denmark)

    Mateo, Jose Antonio; Srba, Jiri; Sørensen, Mathias Grund


    Analysis of workflow processes with quantitative aspects like timing is of interest in numerous time-critical applications. We suggest a workflow model based on timed-arc Petri nets and study the foundational problems of soundness and strong (time-bounded) soundness. We explore the decidability o...

  2. Dahl: Time ripe for DHS net assessment



    Article review Center for Homeland Defense and Security instructor Erik Dahl urges the Department of Homeland Security to follow a practice of its military counterparts and establish an Office of Net Assessment that would gauge future threats and the nation's ability to mitigate them.

  3. Regular Event Structures and Finite Petri Nets

    DEFF Research Database (Denmark)

    Nielsen, M.; Thiagarajan, P.S.


    We present the notion of regular event structures and conjecture that they correspond exactly to finite 1-safe Petri nets. We show that the conjecture holds for the conflict-free case. Even in this restricted setting, the proof is non-trivial and involves a natural subclass of regular event...

  4. Net escapement of Antartic krill in trawls

    DEFF Research Database (Denmark)

    Krafft, B.A.; Krag, Ludvig Ahm; Herrmann, Bent

    This document describes the aims and methodology of a three year project (commenced in 2012) entitled Net Escapement of Antarctic krill in Trawls (NEAT). The study will include a morphology based mathematical modeling (FISHSELECT) of different sex and maturity groups of Antarctic krill (Euphausia...

  5. BioNet Digital Communications Framework (United States)

    Gifford, Kevin; Kuzminsky, Sebastian; Williams, Shea


    BioNet v2 is a peer-to-peer middleware that enables digital communication devices to talk to each other. It provides a software development framework, standardized application, network-transparent device integration services, a flexible messaging model, and network communications for distributed applications. BioNet is an implementation of the Constellation Program Command, Control, Communications and Information (C3I) Interoperability specification, given in CxP 70022-01. The system architecture provides the necessary infrastructure for the integration of heterogeneous wired and wireless sensing and control devices into a unified data system with a standardized application interface, providing plug-and-play operation for hardware and software systems. BioNet v2 features a naming schema for mobility and coarse-grained localization information, data normalization within a network-transparent device driver framework, enabling of network communications to non-IP devices, and fine-grained application control of data subscription band width usage. BioNet directly integrates Disruption Tolerant Networking (DTN) as a communications technology, enabling networked communications with assets that are only intermittently connected including orbiting relay satellites and planetary rover vehicles.

  6. Programming C# Building NET Applications with C#

    CERN Document Server

    Liberty, Jesse


    Programming C#, the top-selling book on Microsoft's high-performance C# programming language, is now in its fourth edition. Aimed at experienced programmers and web developers, this comprehensive guide focuses on the features and programming patterns that are unique to C#, and fundamental to the programming of web services and web applications on Microsoft's .NET platform.

  7. NetBench. Automated Network Performance Testing

    CERN Document Server

    Cadeddu, Mattia


    In order to evaluate the operation of high performance routers, CERN has developed the NetBench software to run benchmarking tests by injecting various traffic patterns and observing the network devices behaviour in real-time. The tool features a modular design with a Python based console used to inject traffic and collect the results in a database, and a web user

  8. Petri Nets as Models of Linear Logic

    DEFF Research Database (Denmark)

    Engberg, Uffe Henrik; Winskel, Glynn


    The chief purpose of this paper is to appraise the feasibility of Girad's linear logic as a specification language for parallel processes. To this end we propose an interpretation of linear logic in Petri nets, with respect to which we investigate the expressive power of the logic...

  9. OK-Net Arable online knowledge platform

    DEFF Research Database (Denmark)

    Rasmussen, Ilse Ankjær; Jensen, Allan Leck; Jørgensen, Margit Styrbæk


    The complexity of organic farming requires farmers to have a very high level of knowledge and skills, but exchange on organic farming techniques remains limited. In order to increase productivity and quality in organic arable cropping in Europe, the thematic network OK-Net Arable under Horizon 20...

  10. Musings on Sketches, Artists, and Mosquito Nets

    Centers for Disease Control (CDC) Podcasts


    Byron Breedlove reads his essay Musings on Sketches, Artists, and Mosquito Nets about the art of James Whistler and the transmission of vector borne diseases.  Created: 9/23/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 10/20/2014.

  11. Educating College Students of the Net Generation (United States)

    Worley, Karen


    Faculty and administrators of higher education today face a challenge with their student populations, many of whom are part of what is known as the net generation. As students become more technologically advanced, faculty must be technologically ready to meet the needs of students. Many college faculty and administrators are from earlier…

  12. State Space Methods for Timed Petri Nets

    DEFF Research Database (Denmark)

    Christensen, Søren; Jensen, Kurt; Mailund, Thomas


    We present two recently developed state space methods for timed Petri nets. The two methods reconciles state space methods and time concepts based on the introduction of a global clock and associating time stamps to tokens. The first method is based on an equivalence relation on states which makes...

  13. Average Costs versus Net Present Value

    NARCIS (Netherlands)

    E.A. van der Laan (Erwin); R.H. Teunter (Ruud)


    textabstractWhile the net present value (NPV) approach is widely accepted as the right framework for studying production and inventory control systems, average cost (AC) models are more widely used. For the well known EOQ model it can be verified that (under certain conditions) the AC approach gives

  14. Childhood Stress (United States)

    ... Safe Videos for Educators Search English Español Childhood Stress KidsHealth / For Parents / Childhood Stress What's in this ... and feel stress to some degree. Sources of Stress Stress is a function of the demands placed ...

  15. Stress Management (United States)

    Healthy Lifestyle Stress management By Mayo Clinic Staff Stress basics Stress is a normal psychological and physical ... of life. Start practicing stress management techniques today. Stress relief The pace and challenges of modern life ...

  16. Sustained Operations in Confined-Space Military Vehicles

    National Research Council Canada - National Science Library

    Delleman, Nico J; Colaciuri, Véronique; Wiederkehr, Emeric; Valk, Pierre J.L


    This paper reports 2 baseline studies and 1 experiment performed in a confined-space military vehicle concerning the effects on fitness and performance of time in a sitting posture and workstation characteristics...

  17. Confinement of hydrogen at high pressure in carbon nanotubes (United States)

    Lassila, David H [Aptos, CA; Bonner, Brian P [Livermore, CA


    A high pressure hydrogen confinement apparatus according to one embodiment includes carbon nanotubes capped at one or both ends thereof with a hydrogen-permeable membrane to enable the high pressure confinement of hydrogen and release of the hydrogen therethrough. A hydrogen confinement apparatus according to another embodiment includes an array of multi-walled carbon nanotubes each having first and second ends, the second ends being capped with palladium (Pd) to enable the high pressure confinement of hydrogen and release of the hydrogen therethrough as a function of palladium temperature, wherein the array of carbon nanotubes is capable of storing hydrogen gas at a pressure of at least 1 GPa for greater than 24 hours. Additional apparatuses and methods are also presented.

  18. Confined-but-Connected Quantum Solids via Controlled Ligand Displacement

    KAUST Repository

    Baumgardner, William J.


    Confined-but-connected quantum dot solids (QDS) combine the advantages of tunable, quantum-confined energy levels with efficient charge transport through enhanced electronic interdot coupling. We report the fabrication of QDS by treating self-assembled films of colloidal PbSe quantum dots with polar nonsolvents. Treatment with dimethylformamide balances the rates of self-assembly and ligand displacement to yield confined-but-connected QDS structures with cubic ordering and quasi-epitaxial interdot connections through facets of neighboring dots. The QDS structure was analyzed by a combination of transmission electron microscopy and wide-angle and small-angle X-ray scattering. Excitonic absorption signatures in optical spectroscopy confirm that quantum confinement is preserved. Transport measurements show significantly enhanced conductivity in treated films. © 2013 American Chemical Society.

  19. Miniature magnetic bottle confined by circularly polarized laser light

    Energy Technology Data Exchange (ETDEWEB)

    Kolka, E.; Eliezer, S.; Paiss, Y. [Israel Atomic Energy Commission, Yavne (Israel). Soreq Nuclear Research Center


    A new concept of hot plasma confinement in a miniature magnetic bottle induced by circularly polarized laser light is suggested. Magnetic fields generated by circularly polarized laser light may be of the order of megagauss. In this configuration the circularly polarized laser light is used to obtain confinement of a plasma contained in a good conductor vessel. The poloidal magnetic field induced by the circularly polarized laser and the efficiency of laser absorption by the plasma are calculated. The confinement in this scheme is supported by the magnetic forces. The Lawson criterion for a DT plasma might be achieved for number density n = 5``centre dot`` 10{sup 21} cm{sup -3} and confinement time {tau} = 20 ns. The laser and plasma parameters required to obtain an energetic gain are calculated. (Author).

  20. Bounce resonance diffusion coefficients for spatially confined waves

    National Research Council Canada - National Science Library

    Li, Xinxin; Tao, Xin; Lu, Quanmin; Dai, Lei


    ...; therefore, they are not directly applicable to waves that have a finite spatial extent. We theoretically derive and numerically validate a new set of bounce resonance diffusion coefficients for spatially confined waves...

  1. Fatigue cracking of a bare steel first wall in an inertial confinement fusion chamber

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, R. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Abbott, R. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Havstad, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dunne, A. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    Inertial confinement fusion power plants will deposit high energy X-rays onto the outer surfaces of the first wall many times a second for the lifetime of the plant. These X-rays create brief temperature spikes in the first few microns of the wall, which cause an associated highly compressive stress response on the surface of the material. The periodicity of this stress pulse is a concern due to the possibility of fatigue cracking of the wall. We have used finite element analyses to simulate the conditions present on the first wall in order to evaluate the driving force of crack propagation on fusion-facing surface cracks. Analysis results indicate that the X-ray induced plastic compressive stress creates a region of residual tension on the surface between pulses. This tension film will likely result in surface cracking upon repeated cycling. Additionally, the compressive pulse may induce plasticity ahead of the crack tip, leaving residual tension in its wake. However, the stress amplitude decreases dramatically for depths greater than 80–100 μm into the fusion-facing surface. Crack propagation models as well as stress-life estimates agree that even though small cracks may form on the surface of the wall, they are unlikely to propagate further than 100 μm without assistance from creep or grain erosion phenomena.

  2. Enhanced Plasma Confinement in a Magnetic Well by Whistler Waves

    DEFF Research Database (Denmark)

    Balmashnov, A. A.; Juul Rasmussen, Jens


    The propagation of whistler waves in a magnetic field of mirror configuration is investigated experimentally. The strong interaction between waves and particles at the electron-cyclotron resonance leads to enhanced confinement in the magnetic well.......The propagation of whistler waves in a magnetic field of mirror configuration is investigated experimentally. The strong interaction between waves and particles at the electron-cyclotron resonance leads to enhanced confinement in the magnetic well....

  3. Confinement less spectral behavior in hollow-core Bragg fibers

    DEFF Research Database (Denmark)

    Foroni, M.; Passaro, D.; Poli, F.


    The influence of each cross-section geometric parameter on hollow-core Bragg fiber guiding properties has been numerically investigated. Fabricated fibers have been modeled, giving insight into the spectral behavior of the confinement loss. It has been verified that, by changing the amount...... of silica and air in the fiber cladding, it is possible to change the reflection conditions undergone by the field within the core, thus shifting the confinement loss spectrum....

  4. Variational perturbation treatment of the confined hydrogen atom

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, H E Jr, E-mail: [Chemistry Program, Centre College, 600 West Walnut Street, Danville, KY 40422-1394 (United States)


    The Schroedinger equation for the ground state of a hydrogen atom confined at the centre of an impenetrable cavity is treated using variational perturbation theory. Energies calculated from variational perturbation theory are comparable in accuracy to the results from a direct numerical solution. The goal of this exercise is to introduce the student to the effects of confinement on atomic systems using a tractable problem from which insight into variational perturbation theory may be gained.

  5. Understanding quantum confinement in nanowires: basics, applications and possible laws. (United States)

    Mohammad, S Noor


    A comprehensive investigation of quantum confinement in nanowires has been carried out. Though applied to silicon nanowires (SiNWs), it is general and applicable to all nanowires. Fundamentals and applications of quantum confinement in nanowires and possible laws obeyed by these nanowires, have been investigated. These laws may serve as backbones of nanowire science and technology. The relationship between energy band gap and nanowire diameter has been studied. This relationship appears to be universal. A thorough review indicates that the first principles results for quantum confinement vary widely. The possible cause of this variation has been examined. Surface passivation and surface reconstruction of nanowires have been elucidated. It has been found that quantum confinement owes its origin to surface strain resulting from surface passivation and surface reconstruction and hence thin nanowires may actually be crystalline-core/amorphous-shell (c-Si/a-Si) nanowires. Experimental data available in the literature corroborate with the suggestion. The study also reveals an intrinsic relationship between quantum confinement and the surface amorphicity of nanowires. It demonstrates that surface amorphicity may be an important tool to investigate the electronic, optoelectronic and sensorial properties of quantum-confined nanowires.

  6. Modeling safety requirements of an FMS using Petri-nets (United States)

    Hanna, Moheb M.; Buck, A. A.; Smith, R.


    This paper is concerned with the modelling of safety requirements using Petri nets as a tool to model and simulate a Flexible Manufacturing System (FMS). The FMS cell described comprises a pick and place robot, a multi-head drilling machine together with a vision system and illustrates how the hierarchical structure of Petri nets can be used to ensure that all fail- safe requirements are satisfied; block diagrams together with fully detailed example Petri nets are given. The work demonstrates the use of cell and robot control Petro nets together with robot subnets for the x, y and z axes and associated output nets; the control and output nets are linked together with a safety net. Individual machines are linked with the control and safety nets of an FMS at cell level. The paper also illustrates how a Petri net can act as a decision maker during image inspection and identifies the unsafe conditions that can arise within an FMS.

  7. A new variant of Petri net controlled grammars (United States)

    Jan, Nurhidaya Mohamad; Turaev, Sherzod; Fong, Wan Heng; Sarmin, Nor Haniza


    A Petri net controlled grammar is a Petri net with respect to a context-free grammar where the successful derivations of the grammar can be simulated using the occurrence sequences of the net. In this paper, we introduce a new variant of Petri net controlled grammars, called a place-labeled Petri net controlled grammar, which is a context-free grammar equipped with a Petri net and a function which maps places of the net to productions of the grammar. The language consists of all terminal strings that can be obtained by parallelly applying multisets of the rules which are the images of the sets of the input places of transitions in a successful occurrence sequence of the Petri net. We study the effect of the different labeling strategies to the computational power and establish lower and upper bounds for the generative capacity of place-labeled Petri net controlled grammars.

  8. Pneumatic fractures in Confined Granular Media (United States)

    Eriksen, Fredrik K.; Toussaint, Renaud; Jørgen Måløy, Knut; Grude Flekkøy, Eirik; Turkaya, Semih


    We will present our ongoing study of the patterns formed when air flows into a dry, non-cohesive porous medium confined in a horizontal Hele-Shaw cell. This is an optically transparent system consisting of two glass plates separated by 0.5 to 1 mm, containing a packing of dry 80 micron beads in between. The cell is rectangular and has an air-permeable boundary (blocking beads) at one short edge, while the other three edges are completely sealed. The granular medium is loosely packed against the semi-permeable boundary and fills about 80 % of the cell volume. This leaves an empty region at the sealed side, where an inlet allows us to set and maintain the air at a constant overpressure (0.1 - 2 bar). For the air trapped inside the cell to relax its overpressure it has to move through the deformable granular medium. Depending on the applied overpressure and initial density of the medium, we observe a range of different behaviors such as seepage through the pore-network with or without an initial compaction of the solid, formation of low density bubbles with rearrangement of particles, granular fingering/fracturing, and erosion inside formed channels/fractures. The experiments are recorded with a high-speed camera at a framerate of 1000 images/s and a resolution of 1024x1024 pixels. We use various image processing techniques to characterize the evolution of the air invasion patterns and the deformations in the surrounding material. The experiments are similar to deformation processes in porous media which are driven by pore fluid overpressure, such as mud volcanoes and hydraulic or pneumatic (gas-induced) fracturing, and the motivation is to increase the understanding of such processes by optical observations. In addition, this setup is an experimental version of the numerical models analyzed by Niebling et al. [1,2], and is useful for comparison with their results. In a directly related project [3], acoustic emissions from the cell plate are recorded during

  9. One-step electro-spinning/netting technique for controllably preparing polyurethane nano-fiber/net. (United States)

    Hu, Juanping; Wang, Xianfeng; Ding, Bin; Lin, Jinyou; Yu, Jianyong; Sun, Gang


    Electro-spinning/netting (ESN) as a cutting-edge technique evokes much interest because of its ability in the one-step preparation of versatile nano-fiber/net (NFN) membranes. Here, a controllable fabrication of polyurethane (PU) NFN membranes with attractive structures, consisting of common electrospun nanofibers and two-dimensional (2D) soap bubble-like structured nano-nets via an ESN process is reported. The unique nanoscaled NFN architecture can be finely controlled by regulating the solution properties and several ESN process parameters. The versatile PU nano-nets comprising interlinked nanowires with ultrathin diameters (5-40 nm) mean that the NFN structured membranes possess several excellent characteristics, such as an extremely large specific surface area, high porosity and large stacking density, which would be particularly useful for applications in ultrafiltration, special protective clothing, ultrasensitive sensors, catalyst support and so on. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Energy Dependence of Moments of Net-Proton, Net-Kaon, and Net-Charge Multiplicity Distributions at STAR

    CERN Document Server



    One of the main goals of the RHIC Beam Energy Scan (BES) program is to study the QCD phase structure, which includes the search for the QCD critical point, over a wide range of chemical potential. Theoretical calculations predict that fluctuations of conserved quantities, such as baryon number (B), charge (Q), and strangeness (S), are sensitive to the correlation length of the dynamical system. Experimentally, higher moments of multiplicity distributions have been utilized to search for the QCD critical point in heavy-ion collisions. In this paper, we report recent efficiency-corrected cumulants and cumulants ratios of the net- proton, net-kaon, and net-charge multiplicity distributions in Au+Au collisions at 7.7, 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV collected in the years 2010, 2011, and 2014 with STAR at RHIC. The centrality and energy dependence of the cumulants up to the fourth order, as well as their ratios, are presented. Furthermore, the comparisons with baseline calculations (Poisson) and non-c...

  11. A compliant mechanism for inspecting extremely confined spaces (United States)

    Mascareñas, David; Moreu, Fernando; Cantu, Precious; Shields, Daniel; Wadden, Jack; El Hadedy, Mohamed; Farrar, Charles


    We present a novel, compliant mechanism that provides the capability to navigate extremely confined spaces for the purpose of infrastructure inspection. Extremely confined spaces are commonly encountered during infrastructure inspection. Examples of such spaces can include pipes, conduits, and ventilation ducts. Often these infrastructure features go uninspected simply because there is no viable way to access their interior. In addition, it is not uncommon for extremely confined spaces to possess a maze-like architecture that must be selectively navigated in order to properly perform an inspection. Efforts by the imaging sensor community have resulted in the development of imaging sensors on the millimeter length scale. Due to their compact size, they are able to inspect many extremely confined spaces of interest, however, the means to deliver these sensors to the proper location to obtain the desired images are lacking. To address this problem, we draw inspiration from the field of endoscopic surgery. Specifically we consider the work that has already been done to create long flexible needles that are capable of being steered through the human body. These devices are typically referred to as ‘steerable needles.’ Steerable needle technology is not directly applicable to the problem of navigating maze-like arrangements of extremely confined spaces, but it does provide guidance on how this problem should be approached. Specifically, the super-elastic nitinol tubing material that allows steerable needles to operate is also appropriate for the problem of navigating maze-like arrangements of extremely confined spaces. Furthermore, the portion of the mechanism that enters the extremely confined space is completely mechanical in nature. The mechanical nature of the device is an advantage when the extremely confined space features environmental hazards such as radiation that could degrade an electromechanically operated mechanism. Here, we present a compliant mechanism

  12. Bistability in a self-assembling system confined by elastic walls: Exact results in a one-dimensional lattice model

    Energy Technology Data Exchange (ETDEWEB)

    Pȩkalski, J.; Ciach, A. [Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warszawa (Poland); Almarza, N. G. [Instituto de Química Física Rocasolano, CSIC, Serrano 119, E-28006 Madrid (Spain)


    The impact of confinement on self-assembly of particles interacting with short-range attraction and long-range repulsion potential is studied for thermodynamic states corresponding to local ordering of clusters or layers in the bulk. Exact and asymptotic expressions for the local density and for the effective potential between the confining surfaces are obtained for a one-dimensional lattice model introduced by J. Pȩkalski et al. [J. Chem. Phys. 138, 144903 (2013)]. The simple asymptotic formulas are shown to be in good quantitative agreement with exact results for slits containing at least 5 layers. We observe that the incommensurability of the system size and the average distance between the clusters or layers in the bulk leads to structural deformations that are different for different values of the chemical potential μ. The change of the type of defects is reflected in the dependence of density on μ that has a shape characteristic for phase transitions. Our results may help to avoid misinterpretation of the change of the type of defects as a phase transition in simulations of inhomogeneous systems. Finally, we show that a system confined by soft elastic walls may exhibit bistability such that two system sizes that differ approximately by the average distance between the clusters or layers are almost equally probable. This may happen when the equilibrium separation between the soft boundaries of an empty slit corresponds to the largest stress in the confined self-assembling system.

  13. 2006 Net Centric Operations Conference - Facilitating Net Centric Operations and Warfare (United States)


    Moderator: Lt Col Kenneth Lang, USAF, Chief, Net Centric Transformational Operations, C4 Transformation Division (US JFCOM/J69) Panelists...of Interest (US JFCOM/J61) - Mr. Troy Turner, Section Head, C4 Interoperability (ACT) - COL Kelly Mayes, USA, Director, Campaign Planning...Deliverables NCAT NIF SCOPE Net Centric Assessment Tools (includes SCOPE & PFCs evaluation) Conceptual Architecture Framework Standards PFCs: Building Codes

  14. Linking a domain thesaurus to WordNet and conversion to WordNet-LMF


    Toral, Antonio; Monachini, Monica; Soria, Claudia; Cuadros Oller, Montserrat; Rigau Claramunt, German; Bosma, Wauter; Vossen, Piek


    We present a methodology to link domain thesauri to general-domain lexica. This is applied in the framework of the KYOTO project to link the Species2000 thesaurus to the synsets of the English WordNet. Moreover, we study the formalisation of this thesaurus according to the ISO LMF standard and its dialect WordNet-LMF. This conversion will allow Species2000 to communicate with the other resources available in the KYOTO architecture. Peer Reviewed

  15. Effects of lateral confinement in natural and leveed reaches of a gravel-bed river: Snake River, Wyoming, USA (United States)

    Leonard, Christina M.; Legleiter, Carl; Overstreet, Brandon T.


    This study examined the effects of natural and anthropogenic changes in confining margin width by applying remote sensing techniques – fusing LiDAR topography with image-derived bathymetry – over a large spatial extent: 58 km of the Snake River, Wyoming, USA. Fused digital elevation models from 2007 and 2012 were differenced to quantify changes in the volume of stored sediment, develop morphological sediment budgets, and infer spatial gradients in bed material transport. Our study spanned two similar reaches that were subject to different controls on confining margin width: natural terraces versus artificial levees. Channel planform in reaches with similar slope and confining margin width differed depending on whether the margins were natural or anthropogenic. The effects of tributaries also differed between the two reaches. Generally, the natural reach featured greater confining margin widths and was depositional, whereas artificial lateral constriction in the leveed reach produced a sediment budget that was closer to balanced. Although our remote sensing methods provided topographic data over a large area, net volumetric changes were not statistically significant due to the uncertainty associated with bed elevation estimates. We therefore focused on along-channel spatial differences in bed material transport rather than absolute volumes of sediment. To complement indirect estimates of sediment transport derived by morphological sediment budgeting, we collected field data on bed mobility through a tracer study. Surface and subsurface grain size measurements were combined with bed mobility observations to calculate armoring and dimensionless sediment transport ratios, which indicated that sediment supply exceeded transport capacity in the natural reach and vice versa in the leveed reach. We hypothesize that constriction by levees induced an initial phase of incision and bed armoring. Because levees prevented bank erosion, the channel excavated sediment by

  16. Comparative study on the mechanical mechanism of confined concrete supporting arches in underground engineering. (United States)

    Lv, Zhijin; Qin, Qian; Jiang, Bei; Luan, Yingcheng; Yu, Hengchang


    In order to solve the supporting problem in underground engineering with high stress, square steel confined concrete (SQCC) supporting method is adopted to enhance the control on surrounding rocks, and the control effect is remarkable. The commonly used cross section shapes of confined concrete arch are square and circular. At present, designers have no consensus on which kind is more proper. To search for the answer, this paper makes an analysis on the mechanical properties of the two shapes of the cross-sections. A full-scale indoor comparative test was carried out on the commonly used straight-wall semi-circular SQCC arch and circular steel confined concrete arch (CCC arch). This test is based on self-developed full-scale test system for confined concrete arch. Our research, combining with the numerical analysis, shows: (1) SQCC arch is consistent with CCC arch in the deformation and failure mode. The largest damages parts are at the legs of both of them. (2) The SQCC arch's bearing capability is 1286.9 kN, and the CCC arch's ultimate bearing capability is 1072.4kN. Thus, the SQCC arch's bearing capability is 1.2 times that of the CCC arch. (3) The arches are subjected to combined compression and bending, bending moment is the main reason for the arch failure. The section moment of inertia of SQCC arch is 1.26 times of that of CCC arch, and the former is better than the latter in bending performance. The ultimate bearing capacity is positively correlated with the size of the moment of inertia. Based on the above research, the engineering suggestions are as follows: (1) To improve the bearing capacity of the arch, the cross-sectional shape of the chamber should be optimized and the arch bearing mode changed accordingly. (2) The key damaged positions, such as the arch leg, should be reinforced, optimizing the state of force on the arch. SQCC arches should be used for supporting in underground engineering, which is under stronger influence of the bending moment and

  17. Effect of confinement on droplet coalescence in shear flow. (United States)

    Chen, Dongju; Cardinaels, Ruth; Moldenaers, Paula


    The effect of confinement on the coalescence of Newtonian (polydimethylsiloxane) droplets in a Newtonian (polyisobutylene) matrix is investigated experimentally. A counter rotating parallel plate device, equipped with a microscopy setup, is used to visualize two interacting droplets during shear flow. The ratio of droplet-to-matrix viscosity is kept constant at 1.1. Droplet collisions are studied for a range of droplet sizes, both in bulk conditions and for gap spacings that are comparable to the droplet size. As a result, we present the first quantitative experimental data set for the coalescence of two equal-sized droplets in a pure shear flow with varying degrees of confinement. Compared to bulk conditions, for droplets smaller than roughly 0.2 times the gap spacing, a slight degree of confinement only decreases the orientation angle at which the droplets coalesce whereas the critical conditions for coalescence remain unaltered. For more confined conditions, the critical capillary number up to which coalescence can occur, increases. Therefore, confinement clearly promotes coalescence. In addition, the droplet trajectories, the time-dependent orientation angle of the droplet pair, and the droplet deformation prior to the coalescence event are systematically studied, and a comparison between the confined and the unconfined situation is provided. It is shown that the presence of two parallel walls can induce changes in the flow field around the droplet pair, which cause an increase of the interaction time between the droplets. Moreover, for sufficiently confined droplets, the additional force originating from the presence of the walls becomes comparable to the hydrodynamic force on the droplet pair, thus influencing the drainage of the matrix film between the droplet surfaces.

  18. Narrative Exposure Therapy as Treatment for Posttraumatic Stress Disorder: An Intervention Study


    Heilmann, Kristine Rysst; Måkestad, Elida


    Narrative Exposure Therapy (NET) is a treatment method defined as a standardized, short-term intervention for treating posttraumatic stress disorder (PTSD). NET has mainly been applied on victims of organized violence and whose life conditions are threatening and unsafe. There are no published studies of NET applied on PTSD patients living in Norway with another trauma history than war-traumas. Aim of the study: To investigate the effect of NET on diagnosed PTSD symptoms, general psychologica...

  19. Fuzzy net present value for engineering analysis

    Directory of Open Access Journals (Sweden)

    Ali Nazeri


    Full Text Available Cash flow analysis is one of the most popular methods for investigating the outcome of an economical project. The costs and benefits of a construction project are often involved with uncertainty and it is not possible to find a precise value for a particular project. In this paper, we present a simple method to calculate the net present value of a cash flow when both costs and benefits are given as triangular numbers. The proposed model of this paper uses Delphi method to figure out the fair values of all costs and revenues and then using fizzy programming techniques, it calculates the fuzzy net present value. The implementation of the proposed model is demonstrated using a simple example.

  20. Design and evaluation of net radiometers (United States)

    Fritschen, Leo J.; Fritschen, Charles L.

    Net radiometer designs were evaluated with respect to long and short wave sensitivities and to the effect of ambient wind on the signal. The design features of the instrument with the best overall performance include: equal sensitivity to long and short wave radiation, a thermal pile which is thermally isolated from the frame, a white guard ring, pathways for internal circulation between the top and bottom hemispheres, and self-supporting windshields. The windshields have O-ring seals, a ball joint is provided for ease of leveling, and ample desiccant is enclosed in the mounting pipe. Under a high radiant load, the net radiometer signal decreased by 2.5, 3.7, and 4.3 percent at wind speeds of 12.5, 4.6, and 7.5 m/s.