Miller, Robert W
2004-04-01
Review of the literature reveals that environmental hazards cause adverse health effects that include sterility, infertility, embryotoxicity, low birth weight, skin lesions, neurodevelopmental defects, immunologic disorders, cancer, and fear of late effects. They have been identified mostly by astute practitioners but also by a bacteriologist, an animal experimentalist, 5 factory workers in childless marriages, and a tipsy bystander in an economically impoverished area of Baltimore. Dust on a parent's work clothes has transported a hazard at work to a hazard at home (lead, asbestos, and chlordecone). Causality is established by showing a dose-response effect and reproducing the effect in studies of other exposed groups or by using another epidemiologic method, eg, prospective instead of retrospective study. Also, the findings should be biologically plausible and not attributable to a concomitant variable such as cigarette smoking. Contrary to front-page newspaper headlines, incidence rates for childhood leukemia are not rising. Preserving specimens for future studies has been valuable: blood from people who were exposed to dioxin in Seveso, Italy; mummified umbilical cords containing methyl mercury at Minamata Bay, Japan; and Guthrie dried blood spots to screen retrospectively for 43 genetic disorders and a specific prenatal cytogenetic abnormality in some children with 1 form of leukemia. Recommendations are given for enhancing interest in environmental hazards and their discovery by clinicians.
Slotkin, Theodore A; Seidler, Frederic J
2010-09-24
Unrelated developmental neurotoxicants can produce similar neurobehavioral outcomes. We examined whether disparate agents affect neuromodulators that control numerous neurotransmitters and circuits, employing PC12 cells to explore the targeting of neuroactive peptides by organophosphates (chlorpyrifos, diazinon), an organochlorine (dieldrin) and a metal (Ni(2+)); we utilized microarrays to profile gene expression for the peptides and their receptors. Chlorpyrifos evoked robust upregulation of cholecystokinin, corticotropin releasing hormone, galanin, neuropeptide Y, neurotensin, preproenkephalin and tachykinin 1; this involved a critical period at the commencement of neurodifferentiation, since the effects were much less notable in undifferentiated PC12 cells. Diazinon targeted a similar but smaller repertoire of neuropeptide genes and the magnitude of the effects was also generally less. Surprisingly, dieldrin shared many of the same neuropeptide targets as the organophosphates and concordance analysis showed significant overlap among all three pesticides. However, dieldrin had more notable effects on neuropeptide receptors, and overlap between diazinon and dieldrin for the receptors led to a stronger resemblance of these two agents than of chlorpyrifos and dieldrin. Ni(2+) was unique, evoking upregulation of only one of the peptides affected by the other agents, while causing downregulation of several others. Nevertheless, there was still significant concordance between Ni(2+) and either diazinon or dieldrin, reflecting similarities toward the receptors. Our results show that neuropeptides are likely to be a prominent target for the developmental neurotoxicity of organophosphates and other neurotoxicants, and further, that the convergence of disparate agents on the same genes and pathways may contribute to similar neurobehavioral outcomes. Copyright 2010 Elsevier B.V. All rights reserved.
Convergence between science and environmental education
Wals, A.E.J.; Brody, M.; Dillon, J.; Stevenson, R.B.
2014-01-01
Urgent issues such as climate change, food scarcity, malnutrition, and loss of biodiversity are highly complex and contested in both science and society (1). To address them, environmental educators and science educators seek to engage people in what are commonly referred to as sustainability challe
Convergent spray process for environmentally friendly coatings
Scarpa, Jack
1995-01-01
Conventional spray application processes have poor transfer efficiencies, resulting in an exorbitant loss in materials, solvents, and time. Also, with ever tightening Environmental Protection Agency (EPA) regulations and Occupational Safety and Health Administration requirements, the low transfer efficiencies have a significant impact on the quantities of materials and solvents that are released into the environment. High solids spray processes are also limited by material viscosities, thus requiring many passes over the surface to achieve a thickness in the 0.125 -inch range. This results in high application costs and a negative impact on the environment. Until recently, requirements for a 100 percent solid sprayable, environmentally friendly, lightweight thermal protection system that can be applied in a thick (greater than 0.125 inch) single-pass operation exceeded the capability of existing systems. Such coatings must be applied by hand lay-up techniques, especially for thermal and/or fire protection systems. The current formulation of these coatings has presented many problems such as worker safety, environmental hazards, waste, high cost, and application constraints. A system which can apply coatings without using hazardous materials would alleviate many of these problems. Potential applications include the aerospace thermal protective specialty coatings, chemical and petroleum industries that require fire-protection coatings that resist impact, chemicals, and weather. These markets can be penetrated by offering customized coatings applied by automated processes that are environmentally friendly.
Organizational frame of environmental policy convergence of Ukraine with EU
Orlovska Juliia Valeriivna
2014-12-01
Full Text Available The aim of the article. The aim of the article is to elaborate organizational frame of environmental policy convergence of Ukraine with EU. The emphasis was placed on one of the goals of Ukraine-European Union Association Agreement, in particular: “to establish conditions for strengthening economic and trade relations, which will lead to the gradual integration Ukraine in the EU internal market”. It has been revealed that the primary constraints that hinder deepening trade relationships between Ukraine and the EU are factors, which by their nature relate to structural and technological aspects of Ukrainian economy. The results of the analysis. The effectiveness of harmonization process can be tracked through the progress in implementing the priorities agenda EU-Ukraine Association. The data of 2013 evidence that Ukraine is gradually moving towards the implementation of the international conventions. A considerable attention should be paid to the progress in diffusion process, because it greatly contributes to the development and applying innovations. The latter is on the agenda for Ukraine as it can solve both the problems concerning technology and environmental effectiveness. Another fundamental problem of poor ecological condition in Ukraine could be seen in uneven spatial concentration of production. Indeed, the present conditions of sector entities activities create significant anthropogenic environmental change, its degradation and destruction due to a combination of large amounts of industrial and agricultural production in some areas and the same. It should be noted that the influence of public on environmental decision-making is absent. Thus, the Law “On regulation of urban development” doesn't realize compliance with the relevant legal procedures by which public participation would be determined in the decision-making on urban development, that in turn eliminates the provisions of the Aarhus Convention “On Access to
Madsen, Ole Brun; Nielsen, Jens Frederik Dalsgaard; Schiøler, Henrik
2002-01-01
Convergence trends between the WAN Internet area, characterized by best effort service provision, and the real time LAN domain, with requirements for guaranteed services, are identified and discussed. A bilateral evolution is identified, where typical bulk service applications from WAN...
Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.
2005-09-01
Call for Papers: Convergence The Journal of Optical Networking (JON) invites submissions to a special issue on Convergence. Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and
Camarero, Mariam [Departamento de Economia. Universidad Jaume I. Campus del Riu Sec. 12071 Castellon (Spain); Picazo-Tadeo, Andres J. [Departamento de Economia Aplicada II. Universidad de Valencia. Avda. dels Tarongers s/n. 46022 Valencia (Spain); Tamarit, Cecilio [Departamento de Economia Aplicada II. Universidad de Valencia. Avda dels Tarongers s/n. 46022 Valencia (Spain)
2008-07-15
In this paper, we test for convergence in the environmental performance of a sample of OECD countries, with data ranging from 1971 to 2002. First, we use Data Envelopment Analysis (DEA) to compute two environmental performance indicators (EPIs) in the production theory framework. Second, we propose the use of a sequential multivariate approach to test for convergence in environmental performance. These tests allow us to reconcile the time series literature with the cross-sectional dimension, which is basic when testing for convergence in regional blocs. The SURE technique is used, which allows for the existence of correlations across the series without imposing a common speed of mean reversion. The empirical results show that the group of countries as a whole, as well as the majority of countries considered on an individual basis (results for some countries vary between EPIs), are catching-up with Switzerland (the benchmark country). (author)
Prasad, Ramjee
2009-01-01
This paper presents the main conclusions which can be drawn from the discussions on Future Communication Systems and lessons on Unpredictable Future of Wireless Communication Systems. Future systems beyond the third generation are already under discussions in international bodies, such as ITU, WW...... and R&D programmes worldwide. The incoming era is characterized by the convergence of networks and access technology and the divergence of applications. Future mobile communication systems should bring something more than only faster data or wireless internet access....
Environmental Policy Convergence in Europe : the impact of international institutions and trade
Holzinger, K.; Knill, C.; Arts, B.
2008-01-01
Abstract Has globalisation led to a convergence in policy-making across nations and, if so, what are the causal mechanisms? This book analyses the extent to which the environmental policies of nation states have converged over the last thirty years and whether this convergence led to a strengthening
Liefländer, Anne K.; Bogner, Franz X.; Kibbe, Alexandra; Kaiser, Florian G.
2015-01-01
One aim of environmental education is fostering sustainable environmental action. Some environmental behaviour models suggest that this can be accomplished in part by improving people's knowledge. Recent studies have identified a distinct, psychometrically supported environmental knowledge structure consisting of system, action-related and…
Liefländer, Anne K.; Bogner, Franz X.; Kibbe, Alexandra; Kaiser, Florian G.
2015-01-01
One aim of environmental education is fostering sustainable environmental action. Some environmental behaviour models suggest that this can be accomplished in part by improving people's knowledge. Recent studies have identified a distinct, psychometrically supported environmental knowledge structure consisting of system, action-related and…
Chun, H S; Gibson, G E; DeGiorgio, L A; Zhang, H; Kidd, V J; Son, J H
2001-02-01
Recent etiological study in twins (Tanner et al. 1999) strongly suggests that environmental factors play an important role in typical, non-familial Parkinson's disease (PD), beginning after age 50. Epidemiological risk factor analyses of typical PD cases have identified several neurotoxicants, including MPP(+) (the active metabolite of MPTP), paraquat, dieldrin, manganese and salsolinol. Here, we tested the hypothesis that these neurotoxic agents might induce cell death in our nigral dopaminergic cell line, SN4741 (Son et al. 1999) through a common molecular mechanism. Our initial experiments revealed that treatment with both MPP(+) and the other PD-related neurotoxicants induced apoptotic cell death in SN4741 cells, following initial increases of H(2)O(2)-related ROS activity and subsequent activation of JNK1/2 MAP kinases. Moreover, we have demonstrated that during dopaminergic cell death cascades, MPP(+), the neurotoxicants and an oxidant, H(2)O(2) equally induce the ROS-dependent events. Remarkably, the oxidant treatment alone induced similar sequential molecular events: ROS increase, activation of JNK MAP kinases, activation of the PITSLRE kinase, p110, by both Caspase-1 and Caspase-3-like activities and apoptotic cell death. Pharmacological intervention using the combination of the antioxidant Trolox and a pan-caspase inhibitor Boc-(Asp)-fmk (BAF) exerted significant neuroprotection against ROS-induced dopaminergic cell death. Finally, the high throughput cDNA microarray screening using the current model identified downstream response genes, such as heme oxygenase-1, a constituent of Lewy bodies, that can be the useful biomarkers to monitor the pathological conditions of dopaminergic neurons under neurotoxic insult.
A Murine Model of Genetic and Environmental Neurotoxicant Action
2001-09-01
Weston for behavior measurements, Brian Rahm and Lisa Bennice for excellent technical assistance. This work was supported by the Department of Defense...Richfield, et al. 23. Lee, M.K., Qiu, D., Sterling, W., Li, W.X., Price, D.L., Copeland , N., and Jenkins, N. (2000) Neuronal and behavioral pathology in
Hoffbauer, Andreas; Ramos, Howard
2014-08-01
This paper examines how and when newspapers, environmental nongovernmental organizations, businesses, and the government converge on environmental events. Using data on the 2010 BP Oil Spill from newspaper articles in the United States, Canada, and the United Kingdom, press releases by Greenpeace and Sierra Club, press releases by BP, Halliburton, Transocean, ExxonMobil, and Shell, and press statements by the White House Press Secretary, we examine an event's potential to trigger convergence of social and political action. By treating events as political actants, we examine arguments from the agenda-setting and social movement literatures on timing, simplicity, and visuality to understand when political actors converge. We find that convergence is related to temporal cycles but not simplicity or visuality.
Slotkin, Theodore A; Seidler, Frederic J
2009-03-31
Unrelated developmental neurotoxicants can elicit similar functional outcomes, whereas agents in the same class may differ. We compared two organophosphate insecticides (chlorpyrifos, diazinon) with an organochlorine (dieldrin) and a metal (Ni(2+)) for similarities and differences in their effects on gene expression encoding subtypes of protein kinase C and their modulators, a cell signaling cascade that integrates the actions of neurotrophic factors involved in brain development. We conducted evaluations in PC12 cells, a model for neuronal development, with each agent introduced at 30 microM for 24 or 72 h, treatments devoid of cytotoxicity. Chlorpyrifos evoked by far the largest effect, with widespread upregulation of multiple genes; the effects were greater during neurodifferentiation than when cells were exposed prior to differentiation. Diazinon had smaller and less widespread effects, consistent with its lesser long-term impact on synaptic function and behavior noted for in vivo exposures in developing rats. Surprisingly, the effects of diazinon, dieldrin and Ni(2+) showed basic similarities despite the fact that all three come from different classes of toxicants. Our findings provide some of the first evidence for a specific mechanistic cascade contributing to the cholinesterase-independent developmental neurotoxicant actions of chlorpyrifos and its differences from diazinon, while at the same time identifying mechanistic convergence between otherwise unrelated toxicants that provides predictions about common neurodevelopmental outcomes. These results further show how combined use of cell cultures and microarray technology can guide future in vivo work on diverse developmental neurotoxicants.
赵若聪; 刘琼; 何晓阳
2013-01-01
线粒体动力学指细胞中的线粒体不断进行分裂融合的一种动态变化,是维持胞内物质与能量运输的重要保障,发动蛋白相关GTP酶1、Fis1、线粒体分裂因子、线粒体融合蛋白1/2和视神经萎缩蛋白1等蛋白为这一过程的直接参与者,它们受到磷酸化、S-亚硝基化、泛素化、小泛素化和蛋白酶解等信号的精密调控.神经细胞的突触形态与功能维持极度依赖线粒体正常分布与功能,而体内外神经毒性物质可能通过干扰线粒体动力学平衡引发神经元能量代谢障碍,活性氧释放增多,并可加速细胞凋亡.越来越多研究表明,线粒体动力学失衡是阿尔兹海默综合征早期病理进程中的关键事件之一.%Mitochondrial dynamics refers to the morphological changes of mitochondria undergoing continuous fission and fusion. Dynamin related GTPase 1, Fis1, mitochondrial fission factor, mitofusin 1/2, and optic atrophy protein 1 have been found to play key roles in this process. They are subject to upstream regulations including phosphorylation, S-ni-trosylation, ubiquitination, sumoylation and proteolysis. Normal mitochondrial functioning is an indispensible part of the maintenance of synapses morphology and function. Neurotoxicants may affect mitochondrial dynamics and then result in the dysfunction of oxidative phosphorylation and increas reactive oxygen species production and neuron apoptosis. More and more researches suggest that the imbalance of mitochondrial dynamics is a key pathological event in the early stage of Alzheimer disease.
AbstractTITLE: A MULTIPLEXED ASSAY FOR DETERMINATION OF NEUROTOXICANT EFFECTS ON SPONTANEOUS NETWORK ACTIVITY AND CELL VIABILITY FROM MICROELECTRODE ARRAYSABSTRACT BODY: Microelectrode array (MEA) recordings are increasingly being used as an in vitro method to detect and characte...
Zhou, Xiaoying
The purpose of this study is to integrate the quantitative environmental performance assessment tools and the theory of multi-objective optimization within the boundary of electronic product systems to support the selection among design alternatives in terms of environmental impact, technical criteria, and economic feasibility. To meet with the requirements that result from emerging environmental legislation targeting electronics products, the research addresses an important analytical methodological approach to facilitate environmentally conscious design and end-of-life management with a life cycle viewpoint. A synthesis of diverse assessment tools is applied on a set of case studies: lead-free solder materials selection, cellular phone design, and desktop display technology assessment. In the first part of this work, an in-depth industrial survey of the status and concerns of the U.S. electronics industry on the elimination of lead (Pb) in solders is described. The results show that the trade-offs among environmental consequences, technology challenges, business risks, legislative compliance and stakeholders' preferences must be explicitly, simultaneously, and systematically addressed in the decision-making process used to guide multi-faceted planning of environmental solutions. In the second part of this work, the convergent optimization of the technical cycle, economic cycle and environmental cycle is addressed in a coherent and systematic way using the application of environmentally conscious design of cellular phones. The technical understanding of product structure, components analysis, and materials flow facilitates the development of "Design for Disassembly" guidelines. A bottom-up disassembly analysis on a "bill of materials" based structure at a micro-operational level is utilized to select optimal end-of-life strategies on the basis of economic feasibility. A macro-operational level life cycle model is used to investigate the environmental consequences
Baek, Dae Hyun; Kim, Tae Gyun; Lim, Hwa Kyung; Kang, Jin Wook; Seong, Su Kyoung; Choi, Seung Eun; Lim, So Yun; Park, Sung Hee; Nam, Bong-hyun; Kim, Eun Hee; Kim, Mun Sin; Park, Kui Lea
2012-08-01
The embryonic stem cell test (EST) is a validated in vitro embryotoxicity test; however, as the inhibition of cardiac differentiation alone is used as a differentiation endpoint in the EST, it may not be a useful test to screen embryotoxic chemicals that affect the differentiation of noncardiac tissues. Previously, methylmercury (MeHg), cadmium and arsenic compounds, which are heavy metals that induce developmental neurotoxicity in vivo, were misclassified as nonembryotoxic with the EST. The aim of this study was to improve the EST to correctly screen such developmental neurotoxicants. We developed a neuronal endpoint (Tuj-1 ID₅₀) using flow cytometry analysis of Tuj-1-positive cells to screen developmental neurotoxicants (MeHg, valproic acid, sodium arsenate and sodium arsenite) correctly using an adherent monoculture differentiation method. Using Tuj-1 ID₅₀ in the EST instead of cardiac ID₅₀, all of the tested chemicals were classified as embryotoxic, while the negative controls were correctly classified as nonembryotoxic. To support the validity of Tuj-1 ID₅₀) , we compared the results from two experimenters who independently tested MeHg using our modified EST. An additional neuronal endpoint (MAP2 ID₅₀), obtained by analyzing the relative quantity of MAP2 mRNA, was used to classify the same chemicals. There were no significant differences in the three endpoint values of the two experimenters or in the classification results, except for isoniazid. In conclusion, our results indicate that Tuj-1 ID₅₀ can be used as a surrogate endpoint of the traditional EST to screen developmental neurotoxicants correctly and it can also be applied to other chemicals.
Slotkin, Theodore A; Seidler, Frederic J
2008-12-01
Developmental exposure to organophosphates (OP) produces long-term changes in serotonin (5HT) synaptic function and associated behaviors, but there are disparities among the different OPs. We contrasted effects of chlorpyrifos and diazinon, as well as non-OP neurotoxicants (dieldrin, Ni(2+)) using undifferentiated and differentiating PC12 cells, a well-established neurodevelopmental model. Agents were introduced at 30 microM for 24 or 72 h, treatments devoid of cytotoxicity, and we evaluated the mRNAs encoding the proteins for 5HT biosynthesis, storage and degradation, as well as 5HT receptors. Chlorpyrifos and diazinon both induced tryptophan hydroxylase, the rate-limiting enzyme for 5HT biosynthesis, but chlorpyrifos had a greater effect, and both agents suppressed expression of 5HT transporter genes, effects that would tend to augment extracellular 5HT. However, whereas chlorpyrifos enhanced the expression of most 5HT receptor subtypes, diazinon evoked overall suppression. Dieldrin evoked even stronger induction of tryptophan hydroxylase, and displayed a pattern of receptor effects similar to that of diazinon, even though they come from different pesticide classes. In contrast, Ni(2+) had completely distinct actions, suppressing tryptophan hydroxylase and enhancing the vesicular monoamine transporter, while also reducing 5HT receptor gene expression, effects that would tend to lower net 5HT function. Our findings provide some of the first evidence connecting the direct, initial mechanisms of developmental neurotoxicant action on specific transmitter pathways with their long-term effects on synaptic function and behavior, while also providing support for in vitro test systems as tools for establishing mechanisms and outcomes of related and unrelated neurotoxicants.
Sumit Sarkar
2014-04-01
Full Text Available Neuronal and vascular brain components are interrelated morphologically, physiologically and developmentally. Due to this close interrelationship, it is often difficult to understand the cause and effect relationship between neuronal vs. vascular dysfunction and pathology. This review will discuss four of the more promising recent developments for detecting vascular pathology, and will compare them with the labeling pattern seen with markers of glial and neuronal pathology; following exposure to well characterized neurotoxicants. To detect the vascular dysfunction in the brain, we recently developed a Fluoro-Turquoise gelatin conjugate (FT-gel, a fluorescent probe that helps to delineate between healthy vs. sclerotic vessels. Similarly, we have investigated the potential for Fluoro-Gold to label in vivo all the endothelial cells in the brain as they co-localize with RECA, an endothelial cell marker. We have also developed Amylo-Glo, a fluorescent tracer that can detect neurotoxic A-beta aggregates in the brain. In this article, we will discuss the potential use of these novel histochemical markers to study the neurotoxicant induced brain. We will also discuss neurovascular strategies that may offer novel therapeutic opportunities for neurodegenerative disorders.
Hansen, Kasper Lage; Greenway, Steven C.; Rosenfeld, Jill A.
2012-01-01
in protein networks driving the development of specific anatomical structures (e.g., outflow tract, ventricular septum, and atrial septum) that are malformed by CHD. This integrative analysis of CHD risk factors and responses suggests a complex pattern of functional interactions between genomic variation...... CHD risk factors and responses, we compiled and integrated comprehensive datasets from studies of CHD in humans and model organisms. We examined two alternative models of potential functional relationships between genes in these datasets: direct convergence, in which CHD risk factors significantly...... and directly impact the same genes and molecules and functional convergence, in which risk factors significantly impact different molecules that participate in a discrete heart development network. We observed no evidence for direct convergence. In contrast, we show that CHD risk factors functionally converge...
... from convergence insufficiency? Symptoms of convergence insufficiency include diplopia (double vision) and headaches when reading. Many patients ... another time or simply watched for symptoms of diplopia or headaches with near work. A patient who ...
Simkins, Tyrell J.; Janis, Kelly L.; McClure, Alison K.; Behrouz, Bahareh; Pappas, Samuel S.; Lehner, Andreas; Kaminski, Norbert E.; Goudreau, John L.; Lookingland, Keith J.; Kaplan, Barbara L. F.
2012-01-01
Motor dysfunctions of Parkinson Disease (PD) are due to the progressive loss of midbrain nigrostriatal dopamine (NSDA) neurons. Evidence suggests a role for cannabinoid receptors in the neurodegeneration of these neurons following neurotoxicant-induced injury. This work evaluates NSDA neurons in CB1/CB2 knockout (KO) mice and tests the hypothesis that CB1/CB2 KO mice are more susceptible to neurotoxicant exposure. NSDA neuronal indices were assessed using unbiased stereological cell counting,...
Kodavanti, Prasada Rao S., E-mail: kodavanti.prasada@epa.gov [Neurotoxicology Branch, NHEERL, ORD, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina (United States); Osorio, Cristina [Systems Proteomics Center, University of North Carolina at Chapel Hill, North Carolina (United States); Program on Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, North Carolina (United States); Royland, Joyce E.; Ramabhadran, Ram [Genetic and Cellular Toxicology Branch, NHEERL, ORD, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina (United States); Alzate, Oscar [Department of Cellular and Developmental Biology, University of North Carolina at Chapel Hill, North Carolina (United States); Systems Proteomics Center, University of North Carolina at Chapel Hill, North Carolina (United States); Program on Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, North Carolina (United States)
2011-11-15
The vast literature on the mode of action of polychlorinated biphenyls (PCBs) indicates that PCBs are a unique model for understanding the mechanisms of toxicity of environmental mixtures of persistent chemicals. PCBs have been shown to adversely affect psychomotor function and learning and memory in humans. Although the molecular mechanisms for PCB effects are unclear, several studies indicate that the disruption of Ca{sup 2+}-mediated signal transduction plays significant roles in PCB-induced developmental neurotoxicity. Culminating events in signal transduction pathways include the regulation of gene and protein expression, which affects the growth and function of the nervous system. Our previous studies showed changes in gene expression related to signal transduction and neuronal growth. In this study, protein expression following developmental exposure to PCB is examined. Pregnant rats (Long Evans) were dosed with 0.0 or 6.0 mg/kg/day of Aroclor-1254 from gestation day 6 through postnatal day (PND) 21, and the cerebellum and hippocampus from PND14 animals were analyzed to determine Aroclor 1254-induced differential protein expression. Two proteins were found to be differentially expressed in the cerebellum following PCB exposure while 18 proteins were differentially expressed in the hippocampus. These proteins are related to energy metabolism in mitochondria (ATP synthase, sub unit {beta} (ATP5B), creatine kinase, and malate dehydrogenase), calcium signaling (voltage-dependent anion-selective channel protein 1 (VDAC1) and ryanodine receptor type II (RyR2)), and growth of the nervous system (dihydropyrimidinase-related protein 4 (DPYSL4), valosin-containing protein (VCP)). Results suggest that Aroclor 1254-like persistent chemicals may alter energy metabolism and intracellular signaling, which might result in developmental neurotoxicity. -- Highlights: Black-Right-Pointing-Pointer We performed brain proteomic analysis of rats exposed to the neurotoxicant
Weak Convergence and Weak Convergence
Narita Keiko
2015-09-01
Full Text Available In this article, we deal with weak convergence on sequences in real normed spaces, and weak* convergence on sequences in dual spaces of real normed spaces. In the first section, we proved some topological properties of dual spaces of real normed spaces. We used these theorems for proofs of Section 3. In Section 2, we defined weak convergence and weak* convergence, and proved some properties. By RNS_Real Mizar functor, real normed spaces as real number spaces already defined in the article [18], we regarded sequences of real numbers as sequences of RNS_Real. So we proved the last theorem in this section using the theorem (8 from [25]. In Section 3, we defined weak sequential compactness of real normed spaces. We showed some lemmas for the proof and proved the theorem of weak sequential compactness of reflexive real Banach spaces. We referred to [36], [23], [24] and [3] in the formalization.
Fišer, Cene; Luštrik, Roman; Sarbu, Serban; Flot, Jean-François; Trontelj, Peter
2015-01-01
Phenotypically similar species coexisting in extreme environments like sulfidic water are subject to two opposing eco-evolutionary processes: those favoring similarity of environment-specific traits, and those promoting differences of traits related to resource use. The former group of processes includes ecological filtering and convergent or parallel evolution, the latter competitive exclusion, character displacement and divergent evolution. We used a unique eco-evolutionary study system composed of two independent pairs of coexisting amphipod species (genus Niphargus) from the sulfidic caves Movile in Romania and Frasassi in Italy to study the relative contribution and interaction of both processes. We looked at the shape of the multifunctional ventral channel as a trait ostensibly related to oxygenation and sulfide detoxification, and at body size as a resource-related trait. Phylogenetic analysis suggests that the sulfidic caves were colonized separately by ancestors of each species. Species within pairs were more dissimilar in their morphology than expected according to a null model based on regional species pool. This might indicate competitive interactions shaping the morphology of these amphipod species. Moreover, our results suggest that the shape of the ventral channel is not subject to long-term convergent selection or to the process of environmental filtering, and as such probably does not play a role in sulfide tolerance. Nevertheless, the ancestral conditions reconstructed using the comparative method tended to be more similar than null-model expectations. This shift in patterns may reflect a temporal hierarchy of eco-evolutionary processes, in which initial environmental filtering became later on superseded by character displacement or other competition-driven divergent evolutionary processes.
Pradas, Marc; Pumir, Alain; Huber, Greg; Wilkinson, Michael
2017-07-01
Chaos is widely understood as being a consequence of sensitive dependence upon initial conditions. This is the result of an instability in phase space, which separates trajectories exponentially. Here, we demonstrate that this criterion should be refined. Despite their overall intrinsic instability, trajectories may be very strongly convergent in phase space over extremely long periods, as revealed by our investigation of a simple chaotic system (a realistic model for small bodies in a turbulent flow). We establish that this strong convergence is a multi-facetted phenomenon, in which the clustering is intense, widespread and balanced by lacunarity of other regions. Power laws, indicative of scale-free features, characterize the distribution of particles in the system. We use large-deviation and extreme-value statistics to explain the effect. Our results show that the interpretation of the ‘butterfly effect’ needs to be carefully qualified. We argue that the combination of mixing and clustering processes makes our specific model relevant to understanding the evolution of simple organisms. Lastly, this notion of convergent chaos, which implies the existence of conditions for which uncertainties are unexpectedly small, may also be relevant to the valuation of insurance and futures contracts.
Port, Russell G.; Gandal, Michael J.; Roberts, Timothy P. L.; Siegel, Steven J.; Carlson, Gregory C.
2014-01-01
Most recent estimates indicate that 1 in 68 children are affected by an autism spectrum disorder (ASD). Though decades of research have uncovered much about these disorders, the pathological mechanism remains unknown. Hampering efforts is the seeming inability to integrate findings over the micro to macro scales of study, from changes in molecular, synaptic and cellular function to large-scale brain dysfunction impacting sensory, communicative, motor and cognitive activity. In this review, we describe how studies focusing on neuronal circuit function provide unique context for identifying common neurobiological disease mechanisms of ASD. We discuss how recent EEG and MEG studies in subjects with ASD have repeatedly shown alterations in ensemble population recordings (both in simple evoked related potential latencies and specific frequency subcomponents). Because these disease-associated electrophysiological abnormalities have been recapitulated in rodent models, studying circuit differences in these models may provide access to abnormal circuit function found in ASD. We then identify emerging in vivo and ex vivo techniques, focusing on how these assays can characterize circuit level dysfunction and determine if these abnormalities underlie abnormal clinical electrophysiology. Such circuit level study in animal models may help us understand how diverse genetic and environmental risks can produce a common set of EEG, MEG and anatomical abnormalities found in ASD. PMID:25538564
Port, Russell G; Gandal, Michael J; Roberts, Timothy P L; Siegel, Steven J; Carlson, Gregory C
2014-01-01
Most recent estimates indicate that 1 in 68 children are affected by an autism spectrum disorder (ASD). Though decades of research have uncovered much about these disorders, the pathological mechanism remains unknown. Hampering efforts is the seeming inability to integrate findings over the micro to macro scales of study, from changes in molecular, synaptic and cellular function to large-scale brain dysfunction impacting sensory, communicative, motor and cognitive activity. In this review, we describe how studies focusing on neuronal circuit function provide unique context for identifying common neurobiological disease mechanisms of ASD. We discuss how recent EEG and MEG studies in subjects with ASD have repeatedly shown alterations in ensemble population recordings (both in simple evoked related potential latencies and specific frequency subcomponents). Because these disease-associated electrophysiological abnormalities have been recapitulated in rodent models, studying circuit differences in these models may provide access to abnormal circuit function found in ASD. We then identify emerging in vivo and ex vivo techniques, focusing on how these assays can characterize circuit level dysfunction and determine if these abnormalities underlie abnormal clinical electrophysiology. Such circuit level study in animal models may help us understand how diverse genetic and environmental risks can produce a common set of EEG, MEG and anatomical abnormalities found in ASD.
Russell G Port
2014-12-01
Full Text Available Most recent estimates indicate that 1 in 68 children are affected by an autism spectrum disorder (ASD. Though decades of research have uncovered much about these disorders, the pathological mechanism remains unknown. Hampering efforts is the seeming inability to integrate findings over the micro to macro scales of study, from changes in molecular, synaptic and cellular function to large-scale brain dysfunction impacting sensory, communicative, motor and cognitive activity. In this review, we describe how studies focusing on neuronal circuit function provide unique context for identifying common neurobiological disease mechanisms of ASD. We discuss how recent EEG and MEG studies in subjects with ASD have repeatedly shown alterations in ensemble population recordings (both in simple evoked related potential latencies and specific frequency subcomponents. Because these disease-associated electrophysiological abnormalities have been recapitulated in rodent models, studying circuit differences in these models may provide access to abnormal circuit function found in ASD. We then identify emerging in-vivo and ex-vivo techniques, focusing on how these assays can characterize circuit level dysfunction and determine if these abnormalities underlie abnormal clinical electrophysiology. Such circuit level study in animal models may help us understand how diverse genetic and environmental risks can produce a common set of EEG, MEG and anatomical abnormalities found in ASD.
Wei, Min; Yamada, Takanori; Yamano, Shotaro; Kato, Minoru; Kakehashi, Anna; Fujioka, Masaki; Tago, Yoshiyuki; Kitano, Mistuaki; Wanibuchi, Hideki, E-mail: wani@med.osaka-cu.ac.jp
2013-11-15
Diphenylarsinic acid (DPAA), a chemical warfare-related neurotoxic organic arsenical, is present in the groundwater and soil in some regions of Japan due to illegal dumping after World War II. Inorganic arsenic is carcinogenic in humans and its organic arsenic metabolites are carcinogenic in animal studies, raising serious concerns about the carcinogenicity of DPAA. However, the carcinogenic potential of DPAA has not yet been evaluated. In the present study we found that DPAA significantly enhanced the development of diethylnitrosamine-induced preneoplastic lesions in the liver in a medium-term rat liver carcinogenesis assay. Evaluation of the expression of cytochrome P450 (CYP) enzymes in the liver revealed that DPAA induced the expression of CYP1B1, but not any other CYP1, CYP2, or CYP3 enzymes, suggesting that CYP1B1 might be the enzyme responsible for the metabolic activation of DPAA. We also found increased oxidative DNA damage, possibly due to elevated CYP1B1 expression. Induction of CYP1B1 has generally been linked with the activation of AhR, and we found that DPAA activates the aryl hydrocarbon receptor (AhR). Importantly, the promotion effect of DPAA was observed only at a dose that activated the AhR, suggesting that activation of AhR and consequent induction of AhR target genes and oxidative DNA damage plays a vital role in the promotion effects of DPAA. The present study provides, for the first time, evidence regarding the carcinogenicity of DPAA and indicates the necessity of comprehensive evaluation of its carcinogenic potential using long-term carcinogenicity studies. - Highlights: • DPAA, an environmental neurotoxicant, promotes liver carcinogenesis in rats. • DPAA is an activator of AhR signaling pathway. • DPAA promoted oxidative DNA damage in rat livers. • AhR target gene CYP 1B1 might be involved in the metabolism of DPAA.
Simkins, Tyrell J; Janis, Kelly L; McClure, Alison K; Behrouz, Bahareh; Pappas, Samuel S; Lehner, Andreas; Kaminski, Norbert E; Goudreau, John L; Lookingland, Keith J; Kaplan, Barbara L F
2012-09-01
Motor dysfunctions of Parkinson Disease (PD) are due to the progressive loss of midbrain nigrostriatal dopamine (NSDA) neurons. Evidence suggests a role for cannabinoid receptors in the neurodegeneration of these neurons following neurotoxicant-induced injury. This work evaluates NSDA neurons in CB1/CB2 knockout (KO) mice and tests the hypothesis that CB1/CB2 KO mice are more susceptible to neurotoxicant exposure. NSDA neuronal indices were assessed using unbiased stereological cell counting, high pressure liquid chromatography coupled with electrochemical detection or mass spectrometry, and Western blot. Results reveal that CB1 and CB2 cannabinoid receptor signaling is not necessary for the maintenance of a normally functioning NSDA neuronal system. Mice lacking CB1 and CB2 receptors were found to be equally susceptible to the neurotoxicant 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP). These studies support the use of CB1/CB2 KO mice for investigating the cannabinoid receptor-mediated regulation of the NSDA neuronal system in models of PD.
Lucio G. Costa
2014-01-01
Full Text Available In addition to increased morbidity and mortality caused by respiratory and cardiovascular diseases, air pollution may also negatively affect the brain and contribute to central nervous system diseases. Air pollution is a mixture comprised of several components, of which ultrafine particulate matter (UFPM; <100 nm is of much concern, as these particles can enter the circulation and distribute to most organs, including the brain. A major constituent of ambient UFPM is represented by traffic-related air pollution, mostly ascribed to diesel exhaust (DE. Human epidemiological studies and controlled animal studies have shown that exposure to air pollution may lead to neurotoxicity. In addition to a variety of behavioral abnormalities, two prominent effects caused by air pollution are oxidative stress and neuroinflammation, which are seen in both humans and animals and are confirmed by in vitro studies. Among factors which can affect neurotoxic outcomes, age is considered the most relevant. Human and animal studies suggest that air pollution (and DE may cause developmental neurotoxicity and may contribute to the etiology of neurodevelopmental disorders, including autistic spectrum disorders. In addition, air pollution exposure has been associated with increased expression of markers of neurodegenerative disease pathologies.
Strong path convergence from Loewner driving convergence
Sheffield, Scott
2010-01-01
We show that, under mild assumptions on the limiting curve, a sequence of simple chordal planar curves converges uniformly whenever certain Loewner driving functions converge. We extend this result to random curves. The random version applies in particular to random lattice paths that have chordal SLE as a scaling limit, with kappa less than 8 (non-space-filling). Existing SLE convergence proofs often begin by showing that the Loewner driving functions of these paths (viewed from infinity) converge to Brownian motion. Unfortunately, this is not sufficient, and additional arguments are required to complete the proofs. We show that driving function convergence is sufficient if it can be established for both parametrization directions and a generic target.
Crespo Cuaresma, Jesus; Klasen, Stephan; Wacker, Konstantin M.
2016-01-01
Martin Ravallion ("Why Don't We See Poverty Convergence?" American Economic Review, 102(1): 504-23; 2012) presents evidence against the existence of convergence in global poverty rates despite convergence in household mean income levels and the close linkage between income growth and poverty reduction. We show that this finding is driven by a specification that demands more than simple convergence in poverty headcount rates and assumes a growth elasticity of poverty reduction, which is well-k...
Convergence S-compactifications
Bernd Losert
2014-07-01
Full Text Available Properties of continuous actions on convergence spaces are investigated. The primary focus is the characterization as to when a continuous action on a convergence space can be continuously extended to an action on a compactification of the convergence space. The largest and smallest such compactifications are studied.
Manganese (Mn) is a nutrient and neurotoxicant sometimes associated with mood, motor and neurological effects. Reports of health effects from occupational exposure to Mn are well known, but the reported links to environmental airborne Mn (Mn-Air) are less conclusive. Marietta, OH...
Manganese (Mn) is a nutrient and neurotoxicant sometimes associated with mood, motor and neurological effects. Reports of health effects from occupational exposure to Mn are well known, but the reported links to environmental airborne Mn (Mn-Air) are less conclusive. Marietta, OH...
Converged Registries Solution (CRS)
Department of Veterans Affairs — The Converged Registries platform is a hardware and software architecture designed to host individual patient registries and eliminate duplicative development effort...
袁亚湘
1995-01-01
The DFP method is one of the most famous numerical algorithms for unconstrained optimization. For uniformly convex objective functions convergence properties of the DFP method are studied. Several conditions that can ensure the global convergence of the DFP method are given.
Convergence of Fuzzy Set Sequences
FENG Yu-hu
2002-01-01
There are more than one mode of convergence with respect to the fuzzy set sequences. In this paper,common six modes of convergence and their relationships are discussed. These six modes are convergence in uniform metric D, convergence in separable metric Dp or D*p, 1 ≤ p ＜∞, convergence in level set, strong convergence in level set and weak convergence. Suitable counterexamples are given. The necessary and sufficient conditions of convergence in uniform metric D are described. Some comme nts on the convergence of LRfuzzy number sequences are represented.
R. Siriram
2012-01-01
Full Text Available
ENGLISH ABSTRACT: Technology is a catalyst for competitive advantage. However, it is how technology is used that leads to a firm’s improved performance. In this article, an investigative framework is constructed to understand better what strategically drives new technology adoption. The strategic drivers include technology and business strategy alignment, better technology planning and selection of new technologies, the effects on a firm’s culture and climate, links to a firm’s organisational and environmental evolution, and benefits through convergence and collaboration. Using an investigative framework, it is shown how the strategic drivers link to improve a firm’s performance, producing competitive advantage. The investigative framework is tested using structural equation modelling. Various hypotheses are formed, and recommendations for further research are made.
AFRIKAANSE OPSOMMING: Tegnologie is ‘n katalisator vir mededingende voordeel. Dit is egter hoe tegnologie aangewend word wat aanleiding gee tot ‘n onderneming se verbeterde prestasie. In hierdie artikel word ‘n ondersoekende raamwerk gekonstrueer om insig te kry in dit wat die aanvaarding van nuwe tegnologie strategies dryf. Die strategiese dryfvere sluit in die belyning van tegnologie en ondernemingstrategie, beter tegnologiebeplanning en seleksie van nuwe tegnologieë, die effek op ‘n onderneming se kultuur en klimaat, koppeling na ‘n onderneming se organisatoriese en omgewingsevolusie, en voordele verkry deur konvergensie en samewerking. Deur ‘n ondersoekende raamwerk te gebruik, word daar getoon dat die strategiese dryfvere koppel om ‘n onderneming se prestasie te verbeter en sodoende ‘n mededingende voordeel te skep. Die raamwerk word getoets en hipoteses geformuleer waarna aanbevelings oor verdere navorsing aan die hand gedoen word.
Helen Kopnina
2015-11-01
Full Text Available While the original objective of environmental education (EE and education for sustainable development (ESD acquired an awareness of the natural world and its current plight, animal welfare (AW, animal rights (AR, and deep ecology (DE have often been absent within EE and ESD. AW and AR focus their attention on individual animals, while the DE perspective recognizes the intrinsic value of the environment. In this article, we shall discuss how the integration of these three approaches within EE/ESD can and should be improved, with particular reference to the ethical underpinnings of educational scholarship and practice. This article will argue that these three positions are well placed to enhance the democratic practices of EE/ESD through the adoption of an inclusive pluralism that embraces representation of non-human species and recognizes their interests.
Yang, Sarah; Sung, Joohon; Kim, Ji-Hae; Song, Yun-Mi; Lee, Kayoung; Kim, Han-Na; Kim, Hyung-Lae; Cloninger, C Robert
2015-04-01
Temperament and Character Inventory (TCI) is a comprehensive personality inventory that is widely used in behavioral genetics. The original theory suggested that temperament traits were under genetic influences, whereas character traits were gradually built by an interaction between temperaments and environment until early adulthood. This study attempted to evaluate TCI by examining the genetic and environmental contributions to personality with particular attention to spousal effects. From 687 families, a total of 3459 Korean adult individuals completed the survey. Among them, there were 542 Monozygotic (MZ) twin pairs and 122 Dizygotic twin pairs. Intraclass correlation coefficients (ICCs) and heritability were calculated to examine the genetic and shared environmental contributions to personality. Moderate genetic contributions (0.17-0.43) were found for all TCI traits along with the evidence of shared environment (0.11-0.31) for harm avoidance (HA) and all characters. The ICCs of TCI in MZ pairs ranged 0.36-0.46. Spouses' had little resemblance for temperament, whereas for character dimensions, spouses (0.27-0.38) were more similar than first degree relatives (0.10-0.29). Resemblance between spouses increased with duration of marriage for most characters and HA. When the growing similarities between spouses were compared with their MZ cotwins' for subgroup of 81 trios, self-directedness (SD) of character showed even more similarities toward their spouses than cotwins as partnership duration increased (r = 0.32). Our findings with regard to change in SD into late adulthood support the psychobiological theory of temperament and character, which suggests that both personality domains have distinct developmental trajectories despite equally large genetic influences.
Nonaccommodative convergence excess.
von Noorden, G K; Avilla, C W
1986-01-15
Nonaccommodative convergence excess is a condition in which a patient has orthotropia or a small-angle esophoria or esotropia at distance and a large-angle esotropia at near, not significantly reduced by the addition of spherical plus lenses. The AC/A ratio, determined with the gradient method, is normal or subnormal. Tonic convergence is suspected of causing the convergence excess in these patients. Nonaccommodative convergence excess must be distinguished from esotropia with a high AC/A ratio and from hypoaccommodative esotropia. In 24 patients treated with recession of both medial recti muscles with and without posterior fixation or by posterior fixation alone, the mean correction of esotropia was 7.4 prism diopters at distance and 17 prism diopters at near.
Convergent Aeronautics Solutions Project
National Aeronautics and Space Administration — The Convergent Aeronautics Solutions (CAS) Project uses short-duration activities to establish early-stage concept and technology feasibility for high-potential...
Fixed mobile convergence handbook
Ahson, Syed A
2010-01-01
From basic concepts to future directions, this handbook provides technical information on all aspects of fixed-mobile convergence (FMC). The book examines such topics as integrated management architecture, business trends and strategic implications for service providers, personal area networks, mobile controlled handover methods, SIP-based session mobility, and supervisory and notification aggregator service. Case studies are used to illustrate technical and systematic implementation of unified and rationalized internet access by fixed-mobile network convergence. The text examines the technolo
Subsequential Convergence Conditions
Dik Mehmet
2007-01-01
Full Text Available Let be a sequence of real numbers and let be any regular limitable method. We prove that, under some assumptions, if a sequence or its generator sequence generated regularly by a sequence in a class of sequences is a subsequential convergence condition for , then for any integer , the repeated arithmetic means of , , generated regularly by a sequence in the class , is also a subsequential convergence condition for .
NONE
2012-12-15
This book explains IT-BT convergence technology as the future technology, which includes a prolog, easy IT-BT convergence technology that has infinite potentials for new value, policy of IT-BT convergence technology showing the potential of smart Korea, IT-BT convergence opening happy future, for the new future of IT powerful nation Korea with IT-BT convergence technology and an epilogue. This book reveals the conception, policy, performance and future of IT-BT convergence technology.
Dishaw, Laura V. [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States); Powers, Christina M. [Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710 (United States); Ryde, Ian T.; Roberts, Simon C. [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States); Seidler, Frederic J.; Slotkin, Theodore A. [Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710 (United States); Stapleton, Heather M., E-mail: heather.stapleton@duke.edu [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States)
2011-11-15
Organophosphate flame retardants (OPFRs) are used as replacements for the commercial PentaBDE mixture that was phased out in 2004. OPFRs are ubiquitous in the environment and detected at high concentrations in residential dust, suggesting widespread human exposure. OPFRs are structurally similar to neurotoxic organophosphate pesticides, raising concerns about exposure and toxicity to humans. This study evaluated the neurotoxicity of tris (1,3-dichloro-2-propyl) phosphate (TDCPP) compared to the organophosphate pesticide, chlorpyrifos (CPF), a known developmental neurotoxicant. We also tested the neurotoxicity of three structurally similar OPFRs, tris (2-chloroethyl) phosphate (TCEP), tris (1-chloropropyl) phosphate (TCPP), and tris (2,3-dibromopropyl) phosphate (TDBPP), and 2,2 Prime ,4,4 Prime -tetrabromodiphenyl ether (BDE-47), a major component of PentaBDE. Using undifferentiated and differentiating PC12 cells, changes in DNA synthesis, oxidative stress, differentiation into dopaminergic or cholinergic neurophenotypes, cell number, cell growth and neurite growth were assessed. TDCPP displayed concentration-dependent neurotoxicity, often with effects equivalent to or greater than equimolar concentrations of CPF. TDCPP inhibited DNA synthesis, and all OPFRs decreased cell number and altered neurodifferentiation. Although TDCPP elevated oxidative stress, there was no adverse effect on cell viability or growth. TDCPP and TDBPP promoted differentiation into both neuronal phenotypes, while TCEP and TCPP promoted only the cholinergic phenotype. BDE-47 had no effect on cell number, cell growth or neurite growth. Our results demonstrate that different OPFRs show divergent effects on neurodifferentiation, suggesting the participation of multiple mechanisms of toxicity. Additionally, these data suggest that OPFRs may affect neurodevelopment with similar or greater potency compared to known and suspected neurotoxicants.
Gale, R. W.
1997-05-01
The likelihood of convergence in the electric power industry in Canada and the United Sates was examined, and the impact of such a development with respect to electricity and natural gas was explored. Based on developments to date, convergence between gas and electric utilities was considered an inevitable step towards the ultimate consolidation of the energy industry as a whole. Characteristics shared by gas and electric utilities were described, and likely developments leading to convergence of the two industries were reviewed. According to this author the competition between the opposing utilities will lead to price wars, loss leaders and other marketing strategies. Prices will be set by supply and demand principles. While users will be able to select customized, money-saving energy solutions, for suppliers, the new utility market will be a Darwinian battle royale, where only the most viable will survive. The end result will be a larger market dominated by a few super players.
Abdul Hameed Q. A. Al-Tai
2011-01-01
Full Text Available The aim of this paper is to introduce and study the fuzzy neighborhood, the limit fuzzy number, the convergent fuzzy sequence, the bounded fuzzy sequence, and the Cauchy fuzzy sequence on the base which is adopted by Abdul Hameed (every real number r is replaced by a fuzzy number r¯ (either triangular fuzzy number or singleton fuzzy set (fuzzy point. And then, we will consider that some results respect effect of the upper sequence on the convergent fuzzy sequence, the bounded fuzzy sequence, and the Cauchy fuzzy sequence.
Prasad, Ramjee; Ruggieri, Marina
2008-01-01
The paper focuses on the revolutionary changes that could characterise the future of networks. Those changes involve many aspects in the conceivement and exploitation of networks: architecture, services, technologies and modeling. The convergence of wired and wireless technologies along...... with the integration of system componennts and the convergence of services (e.g. communications and navigation) are only some of the elements that shape the perpsected mosaic. Authors delineate this vision, highlighting the presence of the space and stratospheric components and the related services as building block...
The convergence of chaotic integrals
Bauer, O; Bauer, Oliver; Mainieri, Ronnie
1995-01-01
We review the convergence of chaotic integrals computed by Monte Carlo simulation, the trace method, dynamical zeta function, and Fredholm determinant on a simple one-dimensional example: the parabola repeller. There is a dramatic difference in convergence between these approaches. The convergence of the Monte Carlo method follows an inverse power law, whereas the trace method and dynamical zeta function converge exponentially, and the Fredholm determinant converges faster than any exponential.
Kolodzy, Janet; Grant, August E.; DeMars, Tony R.; Wilkinson, Jeffrey S.
2014-01-01
The emergence of the Internet, social media, and digital technologies in the twenty-first century accelerated an evolution in journalism and communication that fit under the broad term of convergence. That evolution changed the relationship between news producers and consumers. It broke down the geographical boundaries in defining our communities,…
Coghetto Roland
2015-01-01
We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres) and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections).
Prasad, Ramjee; Ruggieri, Marina
2008-01-01
with the integration of system componennts and the convergence of services (e.g. communications and navigation) are only some of the elements that shape the perpsected mosaic. Authors delineate this vision, highlighting the presence of the space and stratospheric components and the related services as building block...
Coghetto Roland
2015-09-01
Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.
Language Convergence Infrastructure
V. Zaytsev (Vadim); J.M. Fernandes; R. Lämmel (Ralf); J.M.W. Visser (Joost); J. Saraiva
2011-01-01
htmlabstractThe process of grammar convergence involves grammar extraction and transformation for structural equivalence and contains a range of technical challenges. These need to be addressed in order for the method to deliver useful results. The paper describes a DSL and the infrastructure behind
Nevanlinna, O. [Helsinki Univ. of Technology, Espoo (Finland)
1994-12-31
This note summarizes some results on (a monitored version of) the Arnoldi method in Hilbert spaces. The interest in working in infinite dimensional spaces comes partly from the fact that only then can one have meaningful asymptotical statements (which hopefully give some light to the convergence of Arnoldi in large dimensional problems with iteration indices far less than the dimension).
Kolodzy, Janet; Grant, August E.; DeMars, Tony R.; Wilkinson, Jeffrey S.
2014-01-01
The emergence of the Internet, social media, and digital technologies in the twenty-first century accelerated an evolution in journalism and communication that fit under the broad term of convergence. That evolution changed the relationship between news producers and consumers. It broke down the geographical boundaries in defining our communities,…
Species divergence and trait convergence in experimental plant community assembly
Fukami, T.; Bezemer, T.M.; Mortimer, S.R.; Van der Putten, W.H.
2005-01-01
Despite decades of research, it remains controversial whether ecological communities converge towards a common structure determined by environmental conditions irrespective of assembly history. Here, we show experimentally that the answer depends on the level of community organization considered. In
Summable series and convergence factors
Moore, Charles N
1938-01-01
Fairly early in the development of the theory of summability of divergent series, the concept of convergence factors was recognized as of fundamental importance in the subject. One of the pioneers in this field was C. N. Moore, the author of the book under review.... Moore classifies convergence factors into two types. In type I he places the factors which have only the property that they preserve convergence for a convergent series or produce convergence for a summable series. In type II he places the factors which not only maintain or produce convergence but have the additional property that
The Convergent Learning Space:
Kjærgaard, Hanne Wacher; Kjeldsen, Lars Peter; Asmussen, Jørgen Bering
2013-01-01
is described as well as the theoretical construct and hypotheses surrounding the emergence of the concept in technology-rich classrooms, where students bring their own devices and involve their personal learning spaces and networks. The need for new ways of approaching concepts like choice, learning resources......This paper describes the concept of “The Convergent Learning Space” as it is being explored in an ongoing action research project carried out at undergraduate level in select bachelor programs at a Danish University College. The background nature, design, and beginning of this work in progress......, trajectories of participation etc. calls for new action and new pedagogies by teachers in order to secure alignment between students’ worlds and expectations and aims and plans of the teacher. Action research methods are being used to define and test the constituents and variables of the convergent learning...
Subsequential Convergence Conditions
İbrahim Çanak
2007-10-01
Full Text Available Let (un be a sequence of real numbers and let L be any (C,1 regular limitable method. We prove that, under some assumptions, if a sequence (un or its generator sequence (Vn(0(ÃŽÂ”u generated regularly by a sequence in a class Ã°ÂÂ’Âœ of sequences is a subsequential convergence condition for L, then for any integer mÃ¢Â‰Â¥1, the mth repeated arithmetic means of (Vn(0(ÃŽÂ”u, (Vn(m(ÃŽÂ”u, generated regularly by a sequence in the class Ã°ÂÂ’Âœ(m, is also a subsequential convergence condition for L.
无
2006-01-01
Competition has been playing a dominant role among telecommunication equipment manufacturers. In 2006, however, merger overwhelmed competition. In the tide of converging, a large number of equipment manufacturers were involved in mergers. At the same time, telecommunication equipment manufacturers, the most innovative community in the world, drive 3G technology fast in line with its technical roadmap. In addition, Chinese equipment manufacturers cut a figure in world-class telecommunication markets, whic...
IT Convergence and Security 2012
Chung, Kyung-Yong
2013-01-01
The proceedings approaches the subject matter with problems in technical convergence and convergences of security technology. This approach is new because we look at new issues that arise from techniques converging. The general scope of the proceedings content is convergence security and the latest information technology. The intended readership are societies, enterprises, and research institutes, and intended content level is mid- to highly educated personals. The most important features and benefits of the proceedings are the introduction of the most recent information technology and its related ideas, applications and problems related to technology convergence, and its case studies and finally an introduction of converging existing security techniques through convergence security. Overall, through the proceedings, authors will be able to understand the most state of the art information strategies and technologies of convergence security.
Knowledge Convergence and Collaborative Learning
Jeong, Heisawn; Chi, Michelene T. H.
2007-01-01
This paper operationalized the notion of knowledge convergence and assessed quantitatively how much knowledge convergence occurred during collaborative learning. Knowledge convergence was defined as an increase in common knowledge where common knowledge referred to the knowledge that all collaborating partners had. Twenty pairs of college students…
Convergence Patterns in Latin America
Quiroga, Paola Andrea Barrientos
Literature on convergence among Latin American countries is still scarce compared to other regions. Moreover, almost none of the research connects convergence to the economic history of Latin America and the usual finding is one speed of convergence. In this paper I analyze 32 countries and 108...... years, more observations than any other study. This long span of data allows me to use economic history to explain, analyze, validate, and understand the results of convergence patterns in the region. I find more than one speed of convergence (clubs) related to the known historical background, country...
Medialogy - convergence and transdisciplinarity
Nordahl, Rolf
2007-01-01
for changes in society, developments in taste etc. However, it certainly seems fair to say, that available technology makes a great difference to the development of any art form or practice. With the up rise of new educations such as Medialogy, new aspects of convergence and different forms...... of interdisciplinarity and transdisciplinarity is a pre-requisite for both researchers and students. In this talk we will demonstrate our approach through concrete examples of student productions and projects. We will also display the pedagogical method (problem based learning), that enables students to bridge gaps...... between art and science....
Harrison, Yannick Nehemiah Antonio; Risager, Bjarke Skærlund
2016-01-01
. The article is based on participant observation of the Blockupy event and interviews with a group of Danish activists who also participated. The article constructs sociospatial narrative that unfolds through three different scales of organization: the Blockupy coalition, the participating formal and informal...... organizations, and the activist subject. This narrative explicates the mode of organization as a ‘convergence space’ (cf. Routledge, 2003), with different ‘roots’ and ‘routes’ of organization (cf. Davies, 2012). Thus, through an analysis of the modes of organization constituting this mass protest event......, this article restates the relevance of the concept of organization, which have recently been ignored or understated in favour of master-narratives of networks or the dichotomy of horizontalism and verticality. It concludes by posing a set of questions for further discussion among both activists...
Homology, convergence and parallelism.
Ghiselin, Michael T
2016-01-05
Homology is a relation of correspondence between parts of parts of larger wholes. It is used when tracking objects of interest through space and time and in the context of explanatory historical narratives. Homologues can be traced through a genealogical nexus back to a common ancestral precursor. Homology being a transitive relation, homologues remain homologous however much they may come to differ. Analogy is a relationship of correspondence between parts of members of classes having no relationship of common ancestry. Although homology is often treated as an alternative to convergence, the latter is not a kind of correspondence: rather, it is one of a class of processes that also includes divergence and parallelism. These often give rise to misleading appearances (homoplasies). Parallelism can be particularly hard to detect, especially when not accompanied by divergences in some parts of the body. © 2015 The Author(s).
Notermans Ton
2015-02-01
Full Text Available As economic stagnation continues to mark the EU in the fifth year of the euro zone crisis, political support for integration is waning. The European Parliament elections of 2014 returned a hitherto unparalleled number of Eurosceptic MEPs, with EU-critical parties becoming the largest ones in several Member States. Much of this Euroscepticism is driven by economic polarisation between core and peripheral countries. While an increasing number of voters in the northwestern creditor countries resent having to foot the bill for what they consider economic mismanagement in the periphery, voters in peripheral countries increasingly rebel against what they deem to be an economically catastrophic Diktat from Germany and its allies. Continued political support for European integration will hinge on successful income convergence in the EU but the current dilemma is that such policies might not be politically feasible. Periods of rapid convergence would seem to suggest that success depends on two main policy strategies. First, a monetary policy that promotes credit for productive purposes, leaves inflation control to other instruments, and employs selective credit rationing to prevent asset booms. Second, a vertical industrial policy prioritising selected industrial sectors. The first policy conflicts with the present framework of euro zone monetary policy, but that framework was only installed in the first place because many peripheral countries were desperately in search of an external constraint on domestic distributional conflict. Industrial policies, in turn, require a sufficient degree of state autonomy from business elites in order to be effective, but it is highly questionable whether most states in the EU possess such autonomy. Though there are, as yet hesitant, signs of a reorientation of both monetary and cohesion policy in the EU, the question of the institutional and political preconditions for their successful implementation has been largely
The Convergence in Spatial Tasks
Vladimir P. Kulagin; Victor Y. Tsvetkov; Maiya V. Maksimova
2013-01-01
The article reveals the problem of convergence of direct and inverse problems in Earth Sciences, describes the features and application of these problems, discloses analytical features of direct and inverse problems. The convergence criteria and conditions for convergence were presented. This work is supported by the Grant of the Government of the Russian Federation for support of scientific research, implemented under the supervision of leading scientists in Russian institutions of higher ed...
Molecular mechanisms involved in convergent crop domestication.
Lenser, Teresa; Theißen, Günter
2013-12-01
Domestication has helped to understand evolution. We argue that, vice versa, novel insights into evolutionary principles could provide deeper insights into domestication. Molecular analyses have demonstrated that convergent phenotypic evolution is often based on molecular changes in orthologous genes or pathways. Recent studies have revealed that during plant domestication the causal mutations for convergent changes in key traits are likely to be located in particular genes. These insights may contribute to defining candidate genes for genetic improvement during the domestication of new plant species. Such efforts may help to increase the range of arable crops available, thus increasing crop biodiversity and food security to help meet the predicted demands of the continually growing global population under rapidly changing environmental conditions.
Giant lobelias exemplify convergent evolution.
Givnish, Thomas J
2010-01-14
Giant lobeliads on tropical mountains in East Africa and Hawaii have highly unusual, giant-rosette growth forms that appear to be convergent on each other and on those of several independently evolved groups of Asteraceae and other families. A recent phylogenetic analysis by Antonelli, based on sequencing the widest selection of lobeliads to date, raises doubts about this paradigmatic example of convergent evolution. Here I address the kinds of evidence needed to test for convergent evolution and argue that the analysis by Antonelli fails on four points. Antonelli's analysis makes several important contributions to our understanding of lobeliad evolution and geographic spread, but his claim regarding convergence appears to be invalid. Giant lobeliads in Hawaii and Africa represent paradigmatic examples of convergent evolution.
Giant lobelias exemplify convergent evolution
Givnish Thomas J
2010-01-01
Full Text Available Abstract Giant lobeliads on tropical mountains in East Africa and Hawaii have highly unusual, giant-rosette growth forms that appear to be convergent on each other and on those of several independently evolved groups of Asteraceae and other families. A recent phylogenetic analysis by Antonelli, based on sequencing the widest selection of lobeliads to date, raises doubts about this paradigmatic example of convergent evolution. Here I address the kinds of evidence needed to test for convergent evolution and argue that the analysis by Antonelli fails on four points. Antonelli's analysis makes several important contributions to our understanding of lobeliad evolution and geographic spread, but his claim regarding convergence appears to be invalid. Giant lobeliads in Hawaii and Africa represent paradigmatic examples of convergent evolution.
Notes on Some Convergences in Riesz Space
CHEN Zhi-jie; AI Fu-ju
2007-01-01
An equivalent description of u-uniform convergence is presented first. Then the relations among the order convergence,u-uniform convergence and norm convergence of sequences are discussed in Riesz spaces. An equivalence of the three convergences is brought forward; namely, {fn} is a u-uniform Cauchy sequence. Finally the relations among the three convergences of sequences am also extended to the relations among the convergences of nets in Riesz spaces.
Stochastic Engine Convergence Diagnostics
Glaser, R
2001-12-11
;'burn-in'' period. The MCMC process begins at a particular state, which is selected at random or by design, according to the wish of the user of the engine. After the burn-in period, the chain has essentially forgotten where it started. Moreover, the sample x{sup (t{sub 0})}, x{sup (T{sub 0}+1)},... can be used for most purposes as a random sample from f, even though the x{sup (T{sub 0}+t)}, because of Markovian dependency, are not independent. For example, averages involving x{sup (t{sub 0})}, x{sup (t{sub 0}+1)},... may have an approximate normal distribution. The purpose of this note is to discuss the monitoring techniques currently in place in the stochastic engine software that addresses the issues of burn-in, stationarity, and normality. They are loosely termed ''convergence diagnostics'', in reference to the underlying Markov chains, which converge asymptotically to the desired posterior distribution.
The Convergence of Intelligences
Diederich, Joachim
Minsky (1985) argued an extraterrestrial intelligence may be similar to ours despite very different origins. ``Problem- solving'' offers evolutionary advantages and individuals who are part of a technical civilisation should have this capacity. On earth, the principles of problem-solving are the same for humans, some primates and machines based on Artificial Intelligence (AI) techniques. Intelligent systems use ``goals'' and ``sub-goals'' for problem-solving, with memories and representations of ``objects'' and ``sub-objects'' as well as knowledge of relations such as ``cause'' or ``difference.'' Some of these objects are generic and cannot easily be divided into parts. We must, therefore, assume that these objects and relations are universal, and a general property of intelligence. Minsky's arguments from 1985 are extended here. The last decade has seen the development of a general learning theory (``computational learning theory'' (CLT) or ``statistical learning theory'') which equally applies to humans, animals and machines. It is argued that basic learning laws will also apply to an evolved alien intelligence, and this includes limitations of what can be learned efficiently. An example from CLT is that the general learning problem for neural networks is intractable, i.e. it cannot be solved efficiently for all instances (it is ``NP-complete''). It is the objective of this paper to show that evolved intelligences will be constrained by general learning laws and will use task-decomposition for problem-solving. Since learning and problem-solving are core features of intelligence, it can be said that intelligences converge despite very different origins.
Latchoumycandane, Calivarathan; Anantharam, Vellareddy; Jin, Huajun; Kanthasamy, Anumantha; Kanthasamy, Arthi, E-mail: arthik@iastate.edu
2011-11-15
The neurotoxicant 6-hydroxydopamine (6-OHDA) is used to investigate the cellular and molecular mechanisms underlying selective degeneration of dopaminergic neurons in Parkinson's disease (PD). Oxidative stress and caspase activation contribute to the 6-OHDA-induced apoptotic cell death of dopaminergic neurons. In the present study, we sought to systematically characterize the key downstream signaling molecule involved in 6-OHDA-induced dopaminergic degeneration in cell culture and animal models of PD. Treatment of mesencephalic dopaminergic neuronal N27 cells with 6-OHDA (100 {mu}M) for 24 h significantly reduced mitochondrial activity and increased cytosolic cytochrome c, followed by sequential activation of caspase-9 and caspase-3. Co-treatment with the free radical scavenger MnTBAP (10 {mu}M) significantly attenuated 6-OHDA-induced caspase activities. Interestingly, 6-OHDA induced proteolytic cleavage and activation of protein kinase C delta (PKC{delta}) was completely suppressed by treatment with a caspase-3-specific inhibitor, Z-DEVD-FMK (50 {mu}M). Furthermore, expression of caspase-3 cleavage site-resistant mutant PKC{delta}{sup D327A} and kinase dead PKC{delta}{sup K376R} or siRNA-mediated knockdown of PKC{delta} protected against 6-OHDA-induced neuronal cell death, suggesting that caspase-3-dependent PKC{delta} promotes oxidative stress-induced dopaminergic degeneration. Suppression of PKC{delta} expression by siRNA also effectively protected N27 cells from 6-OHDA-induced apoptotic cell death. PKC{delta} cleavage was also observed in the substantia nigra of 6-OHDA-injected C57 black mice but not in control animals. Viral-mediated delivery of PKC{delta}{sup D327A} protein protected against 6-OHDA-induced PKC{delta} activation in mouse substantia nigra. Collectively, these results strongly suggest that proteolytic activation of PKC{delta} is a key downstream event in dopaminergic degeneration, and these results may have important translational value for
The Convergence in Spatial Tasks
Vladimir P. Kulagin
2013-01-01
Full Text Available The article reveals the problem of convergence of direct and inverse problems in Earth Sciences, describes the features and application of these problems, discloses analytical features of direct and inverse problems. The convergence criteria and conditions for convergence were presented. This work is supported by the Grant of the Government of the Russian Federation for support of scientific research, implemented under the supervision of leading scientists in Russian institutions of higher education in the field "Space Research and Technologies" in 2011–2013.
WEAK CONVERGENCE OF SOME SERIES
2000-01-01
This paper continues the study of [1] on weak functions.The weak convergence theory is investigated in complex analysis,Fourier transform and Mellin transform.A Mobius inverse formula of weak functions is obtained.
Dynamical Convergence Trajectory in Networks
TAN Ning; ZHANG Yun-Jun; OUYANG Qi; GENG Zhi
2005-01-01
@@ It is well known that topology and dynamics are two major aspects to determine the function of a network. We study one of the dynamic properties of a network: trajectory convergence, i.e. how a system converges to its steady state. Using numerical and analytical methods, we show that in a logical-like dynamical model, the occurrence of convergent trajectory in a network depends mainly on the type of the fixed point and the ratio between activation and inhibition links. We analytically proof that this property is induced by the competition between two types of state transition structures in phase space: tree-like transition structure and star-like transition structure. We show that the biological networks, such as the cell cycle network in budding yeast, prefers the tree-like transition structures and suggest that this type of convergence trajectories may be universal.
Spaces of Ideal Convergent Sequences
M. Mursaleen
2014-01-01
Full Text Available In the present paper, we introduce some sequence spaces using ideal convergence and Musielak-Orlicz function ℳ=Mk. We also examine some topological properties of the resulting sequence spaces.
Weak entropy inequalities and entropic convergence
GAO FuQing; LI LiNa
2008-01-01
A criterion for algebraic convergence of the entropy is presented and an algebraic convergence result for the entropy of an exclusion process is improved.A weak entropy inequality is considered and its relationship to entropic convergence is discussed.
Weak entropy inequalities and entropic convergence
2008-01-01
A criterion for algebraic convergence of the entropy is presented and an algebraic convergence result for the entropy of an exclusion process is improved. A weak entropy inequality is considered and its relationship to entropic convergence is discussed.
Periodic Convergences: Dance and Computers
deLahunta, Scott
2002-01-01
Published in German and English, this chapter is one of deLahunta's major outputs to emerge from a group of related research outputs, concerning "dance and technology". In it he explores the history of the convergence between dance and computers from the 1960s to the 1990s, arguing that this convergence has been periodic, involving particular artists at particular times, rather than producing a genre of work (as others have speculated). As the mainstream of contemporary dance evolved alongsid...
Needham, C.; McPherson, K.
2004-03-10
We contacted 125 scientists, ethicists, legal scholars, social scientists and informal science educators to participate in a short survey designed to identify critical issues related to nanotechnology. Fifty-six (45%) responded positively, and 46 completed the survey. We then conducted a series of interviews and site visits based on scientific area, and regional representation. Key points are summarized in the attached table. Based on the results of our surveys, we were able to construct three strong areas of ethical, legal, social, and environmental issues around which to build socratic dialogs in a standard Fred Friendly Seminar format. We were also able to identify 4 science center/museum partnerships and a proposal has been submitted to NSF's NISE Program. We are preparing to submit proposals to other agencies and foundations for support.
Needham, C.; McPherson, K.
2004-03-10
We contacted 125 scientists, ethicists, legal scholars, social scientists and informal science educators to participate in a short survey designed to identify critical issues related to nanotechnology. Fifty-six (45%) responded positively, and 46 completed the survey. We then conducted a series of interviews and site visits based on scientific area, and regional representation. Key points are summarized in the attached table. Based on the results of our surveys, we were able to construct three strong areas of ethical, legal, social, and environmental issues around which to build socratic dialogs in a standard Fred Friendly Seminar format. We were also able to identify 4 science center/museum partnerships and a proposal has been submitted to NSF's NISE Program. We are preparing to submit proposals to other agencies and foundations for support.
Measure theory of statistical convergence
CHENG LiXin; LIN GuoChen; LAN YongYi; LIU Hui
2008-01-01
The question of establishing measure theory for statistical convergence has been moving closer to center stage, since a kind of reasonable theory is not only fundamental for unifying various kinds of statistical convergence, but also a bridge linking the studies of statistical convergence across measure theory, integration theory, probability and statistics. For this reason, this paper, in terms of subdifferential, first shows a representation theorem for all finitely additive probability measures defined on the σ-algebra of all subsets of N, and proves that every such measure can be uniquely decomposed into a convex combination of a countably additive probability measure and a statistical measure (i.e. a finitely additive probability measure μ with μ(k) = 0 for all singletons {k}). This paper also shows that classical statistical measures have many nice properties, such as: The set of all such measures endowed with the topology of point-wise convergence on forms a compact convex Hausdorff space; every classical statistical measure is of continuity type (hence, atomless), and every specific class of statistical measures fits a complementation minimax rule for every subset in N. Finally, this paper shows that every kind of statistical convergence can be unified in convergence of statistical measures.
Measure theory of statistical convergence
2008-01-01
The question of establishing measure theory for statistical convergence has been moving closer to center stage, since a kind of reasonable theory is not only fundamental for unifying various kinds of statistical convergence, but also a bridge linking the studies of statistical convergence across measure theory, integration theory, probability and statistics. For this reason, this paper, in terms of subdifferential, first shows a representation theorem for all finitely additive probability measures defined on the σ-algebra A of all subsets of N, and proves that every such measure can be uniquely decomposed into a convex combination of a countably additive probability measure and a statistical measure (i.e. a finitely additive probability measure μ with μ(k) = 0 for all singletons {k}). This paper also shows that classical statistical measures have many nice properties, such as: The set S of all such measures endowed with the topology of point-wise convergence on A forms a compact convex Hausdorff space; every classical statistical measure is of continuity type (hence, atomless), and every specific class of statistical measures fits a complementation minimax rule for every subset in N. Finally, this paper shows that every kind of statistical convergence can be unified in convergence of statistical measures.
Trophic convergence drives morphological convergence in marine tetrapods.
Kelley, Neil P; Motani, Ryosuke
2015-01-01
Marine tetrapod clades (e.g. seals, whales) independently adapted to marine life through the Mesozoic and Caenozoic, and provide iconic examples of convergent evolution. Apparent morphological convergence is often explained as the result of adaptation to similar ecological niches. However, quantitative tests of this hypothesis are uncommon. We use dietary data to classify the feeding ecology of extant marine tetrapods and identify patterns in skull and tooth morphology that discriminate trophic groups across clades. Mapping these patterns onto phylogeny reveals coordinated evolutionary shifts in diet and morphology in different marine tetrapod lineages. Similarities in morphology between species with similar diets-even across large phylogenetic distances-are consistent with previous hypotheses that shared functional constraints drive convergent evolution in marine tetrapods.
Digital Convergence and Content Regulation
Michael John Starks
2014-12-01
Full Text Available Broadcasting, Press and Internet journalism systems of distribution are converging: the same infrastructure can deliver all three historically separate services. Reception devices mirror this: the Connected TV, the tablet and the smart phone overlap in their functionality. Service overlaps are evident too, with broadcasters providing online and on-demand services and newspapers developing electronic versions. Does this mean that media regulation policies must converge too?My argument is that they should, though only where historically different communications are now fulfilling a similar function, e.g. broadcaster online services and electronic versions of newspapers. Convergence requires a degree of harmonisation and, to this end, I advocate a review of UK broadcasting's 'due impartiality' requirement and of the UK's application of the public service concept. I also argue for independent self-regulation (rather than state-based regulation of non-public-service broadcasting journalism.
Order Handling in Convergent Environments
Vrtanoski, Jordan
2012-01-01
The rapid development of IT&T technology had big impact on the traditional telecommunications market, transforming it from monopolistic market to highly competitive high-tech market where new services are required to be created frequently. This paper aims to describe a design approach that puts order management process (as part of enterprise application integration) in function of rapid service creation. In the text we will present a framework for collaborative order handling supporting convergent services. The design splits the order handling processes in convergent environments in three business process groups: order capture, order management and order fulfillment. The paper establishes abstract framework for order handling and provides design guidelines for transaction handling implementation based on the checkpoint and inverse command strategy. The proposed design approach is based in a convergent telecommunication environment. Same principles are applicable in solving problems of collaboration in fun...
Are China and Europe converging?
Bastianin; Andrea; Cattanceo; Cristina; Markandya; Anil
2009-01-01
This analysis aims at giving a flavour of what is happening between the European and Chinese markets with reference to selected energy indicators and economic variables. More precisely the analysis is concerned with the convergence between European countries (EU15 + Norway) and China in terms of both per capita GDP and "sustainability indicators". The variables we refer to as "sustainability indicators" are two: energy intensity (EI) and carbon intensity (CI). The paths of such variables will be investigated both looking at the economy as a whole and by analysing what is happening in three sectors of economic activity, namely industry, agriculture and services. It finds strong evidence of convergence in energy intensity and carbon intensity between the EU and China, with rates fast enough to achieve 90% convergence in a matter of two decades.
Converging Information and Communication Systems
Øst, Alexander
2003-01-01
This Ph.D.-project investigates the process of convergence between television and computers. Identifying three “promises of convergence”: interoperability, quality and interactivity, the project examines the key properties of the computer and television sectors, which have had - or are expected...... in the future to have - significant importance to the process and consequences of the convergence. The project focuses on the appliances, i.e. the TV sets, the computers and their peripheral equipment. It also takes into account the infrastructure and signals, which contain and deliver the information...... and communication, as well as the nature of the content and the usage scenarios of consumers....
Statistical convergence of order $\\alpha$ in probability
Pratulananda Das; Sanjoy Ghosal; Sumit Som
2016-01-01
In this paper ideas of different types of convergence of a sequence of random variables in probability, namely, statistical convergence of order $\\alpha$ in probability, strong $p$-Ces$\\grave{\\mbox{a}}$ro summability of order $\\alpha$ in probability, lacunary statistical convergence or $S_{\\theta}$-convergence of order $\\alpha$ in probability, ${N_{\\theta}}$-convergence of order $\\alpha$ in probability have been introduced and their certain basic properties have been studied.
Digital Convergence and Content Regulation
Starks, Michael John
2014-01-01
abstractBroadcasting, Press and Internet journalism systems of distribution are converging: the same infrastructure can deliver all three historically separate services. Reception devices mirror this: the Connected TV, the tablet and the smart phone overlap in their functionality. Service overlaps a
Industrial Evolution Through Complementary Convergence
Frøslev Christensen, Jens
2011-01-01
The article addresses the dynamics through which product markets become derailed from early product life cycle (PLC)-tracks and engaged in complementary convergence with other product markets or industries. We compare and contrast the theories that can explain, respectively, the PLC...
System Convergence in Transport Modelling
Rich, Jeppe; Nielsen, Otto Anker; Cantarella, Guilio E.
2010-01-01
-of-successive-averages (MSA) have been proposed. Convergence of the MSA under fairly weak regularity conditions was shown in Robbins and Monro (1951). The iteration between demand and assignment ? the external equilibrium ? are in many models either decoupled or follow a very simple iteration pattern. However, as demand...
Convergence of a Catalan Series
Koshy, Thomas; Gao, Zhenguang
2012-01-01
This article studies the convergence of the infinite series of the reciprocals of the Catalan numbers. We extract the sum of the series as well as some related ones, illustrating the power of the calculus in the study of the Catalan numbers.
Lotfi Tadj
1993-01-01
Full Text Available Although intended for college teachers/students, Converge presents a feature that may interest all scientists: it allows an easy export of graphic files to most known word processors, specifically to the ℙ, Version 2.1, a powerful WYSIWYG mathematical word processor.
Exponential convergence rate in entropy
Mu-Fa Chen
2007-01-01
The exponential convergence rate in entropy is studied for symmetric forms, with a specia! attention to the Markov chain with a state space having two points only. Some upper and lower bounds of the rate are obtained and five examples with precise or qualitatively exact estimates are presented.
Convergence analysis of cautious control
ZHANG Yanxia; GUO Lei
2006-01-01
In this paper, we present a theoretical analysis on stability and convergence of the cautious control, which has advantages over the traditional certainty equivalence adaptive control, since it takes the parameter estimation error into account in the design,and is also one-step-ahead optimal in the mean square sense under Gaussian assumptions.
Privatization, convergence, and institutional autonomy
Rooijen, van M.
2011-01-01
Some of the trends incoming for 2011 – greater institutional autonomy, public/private convergence, entrepreneurial management, civic engagement – suggest innovation for hard times, with socio-economic and political rationales increasingly driving borderless developments. Others – open learning and h
Financial Development and Convergence Clubs
N. Basturk (Nalan); R. Paap (Richard); D.J.C. van Dijk (Dick)
2010-01-01
textabstractThis paper studies the economic development process, measured by Gross Domestic Product (GDP), for a large panel of countries. We propose a methodology that identifies groups of countries (convergence clubs) that show similar GDP structures, while allowing for changes in club membersh
Digital Convergence and Content Regulation
Starks, Michael John
2014-01-01
abstractBroadcasting, Press and Internet journalism systems of distribution are converging: the same infrastructure can deliver all three historically separate services. Reception devices mirror this: the Connected TV, the tablet and the smart phone overlap in their functionality. Service overlaps
Madsen, Ole Brun; Nielsen, Jens Frederik Dalsgaard; Schiøler, Henrik
2002-01-01
with the emergence of remote service provision, such as supervision and control of decentralized heating facilities and wind based electrical power production. The reliability issue is addressed from a structural viewpoint, where the concept of Structural QoS (SQoS) is defined to support reliability modelling...... in communication infrastructures. A graph theoretical approach is presented as an approach to reliability management in complex communication infrastructures. Real life examples are provided and specific problems are presented and discussed. Wireless technologies are discussed as a complement, providing not only...
Nikolai Kolev
2003-01-01
placing n labeled balls into N labeled cells. We study the asymptotic behavior of the number of empty cells when (n,N belongs to the right and left domain of attraction. An application to the estimation of characteristics of agreement among a set of raters which independently classify subjects into one of two categories is also indicated. The case when a large number of raters acts following the zero-inflated binomial law with small probability for positive diagnosis is treated using the zero-inflated Poisson approximation.
Quantifying convergence in the sciences
Sara Lumbreras
2016-02-01
Full Text Available Traditional epistemological models classify knowledge into separate disciplines with different objects of study and specific techniques, with some frameworks even proposing hierarchies (such as Comte’s. According to thinkers such as John Holland or Teilhard de Chardin, the advancement of science involves the convergence of disciplines. This proposed convergence can be studied in a number of ways, such as how works impact research outside a specific area (citation networks or how authors collaborate with other researchers in different fields (collaboration networks. While these studies are delivering significant new insights, they cannot easily show the convergence of different topics within a body of knowledge. This paper attempts to address this question in a quantitative manner, searching for evidence that supports the idea of convergence in the content of the sciences themselves (that is, whether the sciences are dealing with increasingly the same topics. We use Latent Dirichlet Analysis (LDA, a technique that is able to analyze texts and estimate the relative contributions of the topics that were used to generate them. We apply this tool to the corpus of the Santa Fe Institute (SFI working papers, which spans research on Complexity Science from 1989 to 2015. We then analyze the relatedness of the different research areas, the rise and demise of these sub-disciplines over time and, more broadly, the convergence of the research body as a whole. Combining the topic structure obtained from the collected publication history of the SFI community with techniques to infer hierarchy and clustering, we reconstruct a picture of a dynamic community which experiences trends, periodically recurring topics, and shifts in the closeness of scholarship over time. We find that there is support for convergence, and that the application of quantitative methods such as LDA to the study of knowledge can provide valuable insights that can help
Proliferating Connections and Communicating Convergence
Aylish Wood
2008-01-01
Full Text Available In this paper I use the work of Niklas Luhmann to explore what pressure the concept of convergence exerts over how we communicate about the changing expressive practices of digital games following the emergence of digital technologies. My claim will be that in its current form, convergence privileges either the human users of technological platforms, or the combination of aesthetic conventions from different media what connects is either the user or the aesthetic code. While neither of these two positions would be likely to deny a reliance on the interplay between humans and technologies, such an interplay is taken for granted rather than explored. By using Luhmann’s version of systems theory, I argue that we can more effectively grasp the interplay of human and technological participants by understanding their combined roles in changing expressive practices.
Concept Convergence in Empirical Domains
Ontañón, Santiago; Plaza, Enric
How to achieve shared meaning is a significant issue when more than one intelligent agent is involved in the same domain. We define the task of concept convergence, by which intelligent agents can achieve a shared, agreed-upon meaning of a concept (restricted to empirical domains). For this purpose we present a framework that, integrating computational argumentation and inductive concept learning, allows a pair of agents to (1) learn a concept in an empirical domain, (2) argue about the concept's meaning, and (3) reach a shared agreed-upon concept definition. We apply this framework to marine sponges, a biological domain where the actual definitions of concepts such as orders, families and species are currently open to discussion. An experimental evaluation on marine sponges shows that concept convergence is achieved, within a reasonable number of interchanged arguments, and reaching short and accurate definitions (with respect to precision and recall).
Optimality Functions and Lopsided Convergence
2015-03-16
Problems involving functions defined in terms of integrals or optimization problems (as the maxi - mization in Example 3), functions defined on infinite...optimization methods in finite time. The key technical challenge associate with the above scheme is to establish ( weak ) consistency. In the next...Theorem 4.3. In view of this result, it is clear that ( weak ) consistency will be ensured by epi-convergence of the approximating objective functions and
ACCOUNTING CONVERGENCE ON ECONOMIC CRISIS
HOLBAN ONCIOIU IONICA
2010-12-01
Full Text Available If normalization accounting is the process of harmonizing the presentation of financial statements, accounting methods and terminology, accounting convergence is the process by which accounting standards are developed in a way that is able to lead to the same fact or purpose, by highlighting the similarity of national - regional - international. This paper put in light the importance of the normalization and harmonization process, what its done in and what we have to do for that in Romania.
Surface meshing with curvature convergence
Li, Huibin
2014-06-01
Surface meshing plays a fundamental role in graphics and visualization. Many geometric processing tasks involve solving geometric PDEs on meshes. The numerical stability, convergence rates and approximation errors are largely determined by the mesh qualities. In practice, Delaunay refinement algorithms offer satisfactory solutions to high quality mesh generations. The theoretical proofs for volume based and surface based Delaunay refinement algorithms have been established, but those for conformal parameterization based ones remain wide open. This work focuses on the curvature measure convergence for the conformal parameterization based Delaunay refinement algorithms. Given a metric surface, the proposed approach triangulates its conformal uniformization domain by the planar Delaunay refinement algorithms, and produces a high quality mesh. We give explicit estimates for the Hausdorff distance, the normal deviation, and the differences in curvature measures between the surface and the mesh. In contrast to the conventional results based on volumetric Delaunay refinement, our stronger estimates are independent of the mesh structure and directly guarantee the convergence of curvature measures. Meanwhile, our result on Gaussian curvature measure is intrinsic to the Riemannian metric and independent of the embedding. In practice, our meshing algorithm is much easier to implement and much more efficient. The experimental results verified our theoretical results and demonstrated the efficiency of the meshing algorithm. © 2014 IEEE.
Convergences and divergences in mortality
2004-04-01
Full Text Available Abdel Omran's 1971 theory of "Epidemiologic Transition" was the first attempt to account for the extraordinary advances in health care made in industrialized countries since the 18th century. In the framework of the Demographic Transition, it implied a general convergence of life expectancies toward a limit imposed by the new epidemiological features of modern societies. However, important failures, occurred in the past decades (mainly the health crisis in Eastern Europe and AIDS in Africa, seem to have stopped that process of convergence. In fact such failures do not really contradict the theory. The latter is much more ruined by the unexpected dramatic improvement in the field of cardiovascular disease experienced since the seventies, which results in a new step of a more general process. On the basis of the broader concept of "Health Transition" initiated by Julio Frenk et al., the present paper tries to rethink the full process in term of divergence/convergence sequences inferred by successive major changes in health technologies and strategies.
CONVERGENCE THEOREMS FOR THE AOR METHOD
黄廷祝; 王广彬
2002-01-01
Practical sufficient conditions for the convergence of the AOR method and a practical sufficient condition for H-matrices are studied. The obtained convergence conditions suited to matrices which need not to be diagonally dominant.
User Configurations and Convergence in Consumer Electronics
Jørgensen, Ulrik
2000-01-01
Convergence has been a technical fix motivated by the digital developments in media technologies.......Convergence has been a technical fix motivated by the digital developments in media technologies....
Fiscal Convergence in an Enlarged European Union
Georgeta VINTILĂ
2014-02-01
Full Text Available Taxation convergence in the European Union has always been a heatedly debated issue, and it has constantly resurfaced to the limelight as more and more fiscal directive proposals are being discussed. The current study is an analysis of the evolution of taxation convergence tendencies within the European Union in recent years, using sigma-convergence and cluster analysis. Our goal is to analyze the fiscal convergence trends in the context of European Union enlargement over the last two decades.
Convergence of barycentric coordinates to barycentric kernels
Kosinka, Jiří
2016-02-12
We investigate the close correspondence between barycentric coordinates and barycentric kernels from the point of view of the limit process when finer and finer polygons converge to a smooth convex domain. We show that any barycentric kernel is the limit of a set of barycentric coordinates and prove that the convergence rate is quadratic. Our convergence analysis extends naturally to barycentric interpolants and mappings induced by barycentric coordinates and kernels. We verify our theoretical convergence results numerically on several examples.
Convergence analysis of combinations of different methods
Kang, Y. [Clarkson Univ., Potsdam, NY (United States)
1994-12-31
This paper provides a convergence analysis for combinations of different numerical methods for solving systems of differential equations. The author proves that combinations of two convergent linear multistep methods or Runge-Kutta methods produce a new convergent method of which the order is equal to the smaller order of the two original methods.
TAUBERIAN THEOREMS FOR WEAK ALMOST CONVERGENT FUNCTIONS
Meng-Kuang Kuo
2011-01-01
The almost convergent function which was introduced by Raimi [6] and dis- cussed by Ho [4], Das and Nanda [2, 3], is the continuous analogue of almost convergent sequences (see [5]). In this paper, we establish the Tauberian conditions and the Cauchy criteria for weak almost convergent functions on R2+.
Ecomorphological convergence in planktivorous surgeonfishes
Friedman, S. T.
2016-01-26
© 2016 European Society For Evolutionary Biology. Morphological convergence plays a central role in the study of evolution. Often induced by shared ecological specialization, homoplasy hints at underlying selective pressures and adaptive constraints that deterministically shape the diversification of life. Although midwater zooplanktivory has arisen in adult surgeonfishes (family Acanthuridae) at least four independent times, it represents a clearly specialized state, requiring the capacity to swiftly swim in midwater locating and sucking small prey items. Whereas this diet has commonly been associated with specific functional adaptations in fishes, acanthurids present an interesting case study as all nonplanktivorous species feed by grazing on benthic algae and detritus, requiring a vastly different functional morphology that emphasizes biting behaviours. We examined the feeding morphology in 30 acanthurid species and, combined with a pre-existing phylogenetic tree, compared the fit of evolutionary models across two diet regimes: zooplanktivores and nonzooplanktivorous grazers. Accounting for phylogenetic relationships, the best-fitting model indicates that zooplanktivorous species are converging on a separate adaptive peak from their grazing relatives. Driving this bimodal landscape, zooplanktivorous acanthurids tend to develop a slender body, reduced facial features, smaller teeth and weakened jaw adductor muscles. However, despite these phenotypic changes, model fitting suggests that lineages have not yet reached the adaptive peak associated with plankton feeding even though some transitions appear to be over 10 million years old. These findings demonstrate that the selective demands of pelagic feeding promote repeated - albeit very gradual - ecomorphological convergence within surgeonfishes, while allowing local divergences between closely related species, contributing to the overall diversity of the clade. Journal of Evolutionary Biology
Weak* convergence of operator means
Romanov, Alexandr V [Moscow State Institute of Electronics and Mathematics (Technical University), Moscow (Russian Federation)
2011-12-31
For a linear operator U with ||U'n||{<=}const on a Banach space X we discuss conditions for the convergence of ergodic operator nets T{sub {alpha}} corresponding to the adjoint operator U* of U in the W*O-topology of the space EndX*. The accumulation points of all possible nets of this kind form a compact convex set L in EndX*, which is the kernel of the operator, where {Gamma}{sub 0}={l_brace}U{sub n}*, n{>=}0{r_brace}. It is proved that all ergodic nets T{sub {alpha}} weakly* converge if and only if the kernel L consists of a single element. In the case of X=C({Omega}) and the shift operator U generated by a continuous transformation {phi} of a metrizable compactum {Omega} we trace the relationships among the ergodic properties of U, the structure of the operator semigroups L, G and {Gamma}={Gamma}-bar{sub 0}, and the dynamical characteristics of the semi-cascade ({phi},{Omega}). In particular, if cardL=1, then a) for any {omega} element of {Omega} the closure of the trajectory {l_brace}{phi}{sup n}{omega}, n{>=}0{r_brace} contains precisely one minimal set m, and b) the restriction ({phi},m) is strictly ergodic. Condition a) implies the W*O-convergence of any ergodic sequence of operators T{sub n} element of EndX* under the additional assumption that the kernel of the enveloping semigroup E({phi},{Omega}) contains elements obtained from the 'basis' family of transformations {l_brace}{phi}{sup n}, n{>=}0{r_brace} of the compact set {Omega} by using some transfinite sequence of sequential passages to the limit.
SCORE DIGITAL TECHNOLOGY: THE CONVERGENCE
Chernyshov Alexander V.
2013-12-01
Full Text Available Explores the role of digital scorewriters in today's culture, education, and music industry and media environment. The main principle of the development of software is not only publishing innovation (relating to the sheet music, and integration into the area of composition, arrangement, education, creative process for works based on digital technology (films, television and radio broadcasting, Internet, audio and video art. Therefore the own convergence of musically-computer technology is a total phenomenon: notation program combined with means MIDI-sequencer, audio and video editor. The article contains the unique interview with the creator of music notation processors.
Pointwise convergence of Fourier series
Arias de Reyna, Juan
2002-01-01
This book contains a detailed exposition of Carleson-Hunt theorem following the proof of Carleson: to this day this is the only one giving better bounds. It points out the motivation of every step in the proof. Thus the Carleson-Hunt theorem becomes accessible to any analyst.The book also contains the first detailed exposition of the fine results of Hunt, Sjölin, Soria, etc on the convergence of Fourier Series. Its final chapters present original material. With both Fefferman's proof and the recent one of Lacey and Thiele in print, it becomes more important than ever to understand and compare these two related proofs with that of Carleson and Hunt. These alternative proofs do not yield all the results of the Carleson-Hunt proof. The intention of this monograph is to make Carleson's proof accessible to a wider audience, and to explain its consequences for the pointwise convergence of Fourier series for functions in spaces near $äcal Lü^1$, filling a well-known gap in the literature.
Sustainability and Convergence: The Future of Corporate Governance Systems?
Daniela M. Salvioni
2016-11-01
Full Text Available In today’s world, a sustainable approach to corporate governance can be a source of competitive advantage and a long-term success factor for any firm. Sustainable governance requires that the board of directors considers economic, social and environmental expectations in an integrated way, no matter what ownership structure and formal rules of corporate governance apply to the company: this mitigates the traditional differences between insider and outsider systems of corporate governance. Previous studies failed to consider the contribution of sustainability in the process of corporate governance convergence. Therefore, the aim of this article is to fill the gap in the existing literature by means of a qualitative analysis, supporting the international debate about convergence of corporate governance systems. The article describes the evolution of outsider and insider systems in the light of the increasing importance of sustainability in the board’s decision-making and firm’s operation to satisfy the needs of all the company’s stakeholders. According to this, a qualitative content analysis developed with a directed approach completes the theoretical discussion, demonstrating that sustainability can bring de facto convergence between outsider and insider corporate governance systems. The article aims to be a theoretical starting point for future research, the findings of which could also have practical implications: the study encourages the policy makers to translate the sustainable business best practices into laws and recommendations, strengthening the mutual influence between formal and substantial convergence.
Convergent Validity of the PUTS
Valerie Cathérine Brandt
2016-04-01
Full Text Available Premonitory urges are a cardinal feature in Gilles de la Tourette syndrome. Severity of premonitory urges can be assessed with the Premonitory Urge for Tic Disorders Scale (PUTS. However, convergent validity of the measure has been difficult to assess due to the lack of other urge measures.We investigated the relationship between average real-time urge intensity assessed by an in-house developed real-time urge monitor, measuring urge intensity continuously for 5mins on a visual analogue scale, and general urge intensity assessed by the PUTS in 22 adult Tourette patients (mean age 29.8+/- 10.3; 19 male. Additionally, underlying factors of premonitory urges assessed by the PUTS were investigated in the adult sample using factor analysis and were replicated in 40 children and adolescents diagnosed with Tourette syndrome (mean age 12.05 +/- 2.83 SD, 31 male.Cronbach’s alpha for the PUTS10 was acceptable (α = .79 in the adult sample. Convergent validity between average real-time urge intensity scores (as assessed with the real-time urge monitor and the 10-item version of the PUTS (r = .64 and the 9-item version of the PUTS (r = .66 was good. A factor analysis including the 10 items of the PUTS and average real-time urge intensity scores revealed three factors. One factor included the average real-time urge intensity score and appeared to measure urge intensity, while the other two factors can be assumed to reflect the (sensory quality of urges and subjective control, respectively. The factor structure of the 10 PUTS items alone was replicated in a sample of children and adolescents.The results indicate that convergent validity between the PUTS and the real-time urge assessment monitor is good. Furthermore, the results suggest that the PUTS might assess more than one dimension of urges and it may be worthwhile developing different sub-scales of the PUTS assessing premonitory urges in terms of intensity and quality, as well as subjectively
NBIC-Convergence of Machinery and Basic Technologies as the Ecological Factor of Wellbeing
Zhironkin, S. A.; Kolotov, K. A.; Genin, A. E.; Agafonov, F. V.; Kovalevsky, S. A.
2017-01-01
The development of science and technology in the XXI century is on the way of the extensive use of natural resources. As a result, the scientific and technical progress does not initiate the reduction of environmental damage but encourages its cumulative growth. So the environmental problems have become a serious threat to social wellbeing of all mankind. The development of the core technologies doesn’t allow creating the situation in which the new knowledge would generate positive changes in the environment. Therefore, among the issues that define the future of advanced environmental technologies, and potentially significant for the understanding of the humanities, there is the phenomenon of technological convergence and, in particular, the predicted convergence of the nano-, bio-, information and cognitive technologies (NBIC). The consequence of NBIC-convergence may be the transformation of the humanity into a single global mind, which can be linked into a solid set of technologies, establishing united standards for social wellbeing and environmental technologies.
Professional convergence in forensic practice.
Mercer, D; Mason, T; Richman, J
2001-06-01
This paper outlines the development and convergence of forensic science and secure psychiatric services in the UK, locating the professionalization of forensic nursing within a complex web of political, economic, and ideological structures. It is suggested that a stagnation of the therapeutic enterprise in high and medium security provision has witnessed an intrusion of medical power into the societal body. Expanding technologies of control and surveillance are discussed in relation to the move from modernity to postmodernity and the ongoing dynamic of medicalized offending. Four aspects of globalization are identified as impacting upon the organization and application of forensic practice: (i) organized capitalism and the exhaustion of the welfare state; (ii) security versus danger and trust versus risk; (iii) science as a meta-language; and (iv) foreclosure as a mechanism of censorship. Finally, as a challenge for the profession, some predictions are offered about the future directions or demise of forensic nursing.
Mosaic Convergence of Rodent Dentitions
Lazzari, Vincent; Charles, Cyril; Tafforeau, Paul; Vianey-Liaud, Monique; Aguilar, Jean-Pierre; Jaeger, Jean-Jacques; Michaux, Jacques; Viriot, Laurent
2008-01-01
Background Understanding mechanisms responsible for changes in tooth morphology in the course of evolution is an area of investigation common to both paleontology and developmental biology. Detailed analyses of molar tooth crown shape have shown frequent homoplasia in mammalian evolution, which requires accurate investigation of the evolutionary pathways provided by the fossil record. The necessity of preservation of an effective occlusion has been hypothesized to functionally constrain crown morphological changes and to also facilitate convergent evolution. The Muroidea superfamily constitutes a relevant model for the study of molar crown diversification because it encompasses one third of the extant mammalian biodiversity. Methodology/Principal Findings Combined microwear and 3D-topographic analyses performed on fossil and extant muroid molars allow for a first quantification of the relationships between changes in crown morphology and functionality of occlusion. Based on an abundant fossil record and on a well resolved phylogeny, our results show that the most derived functional condition associates longitudinal chewing and non interlocking of cusps. This condition has been reached at least 7 times within muroids via two main types of evolutionary pathways each respecting functional continuity. In the first type, the flattening of tooth crown which induces the removal of cusp interlocking occurs before the rotation of the chewing movement. In the second type however, flattening is subsequent to rotation of the chewing movement which can be associated with certain changes in cusp morphology. Conclusion/Significance The reverse orders of the changes involved in these different pathways reveal a mosaic evolution of mammalian dentition in which direction of chewing and crown shape seem to be partly decoupled. Either can change in respect to strong functional constraints affecting occlusion which thereby limit the number of the possible pathways. Because convergent
Mosaic convergence of rodent dentitions.
Vincent Lazzari
Full Text Available BACKGROUND: Understanding mechanisms responsible for changes in tooth morphology in the course of evolution is an area of investigation common to both paleontology and developmental biology. Detailed analyses of molar tooth crown shape have shown frequent homoplasia in mammalian evolution, which requires accurate investigation of the evolutionary pathways provided by the fossil record. The necessity of preservation of an effective occlusion has been hypothesized to functionally constrain crown morphological changes and to also facilitate convergent evolution. The Muroidea superfamily constitutes a relevant model for the study of molar crown diversification because it encompasses one third of the extant mammalian biodiversity. METHODOLOGY/PRINCIPAL FINDINGS: Combined microwear and 3D-topographic analyses performed on fossil and extant muroid molars allow for a first quantification of the relationships between changes in crown morphology and functionality of occlusion. Based on an abundant fossil record and on a well resolved phylogeny, our results show that the most derived functional condition associates longitudinal chewing and non interlocking of cusps. This condition has been reached at least 7 times within muroids via two main types of evolutionary pathways each respecting functional continuity. In the first type, the flattening of tooth crown which induces the removal of cusp interlocking occurs before the rotation of the chewing movement. In the second type however, flattening is subsequent to rotation of the chewing movement which can be associated with certain changes in cusp morphology. CONCLUSION/SIGNIFICANCE: The reverse orders of the changes involved in these different pathways reveal a mosaic evolution of mammalian dentition in which direction of chewing and crown shape seem to be partly decoupled. Either can change in respect to strong functional constraints affecting occlusion which thereby limit the number of the possible
Cosmic Convergence: Art and Science
Mayo, Elizabeth A.; Zisholtz, E.; Hilton, H.
2010-01-01
The I.P. Stanback Museum and Planetarium is a major educational and teaching resource for South Carolina State University, K-12 schools, other universities and the community of Orangeburg and well beyond. The concept of creating a museum with a planetarium on the campus of SC State was ahead of its time. Today scholars are writing about the unity of creative disciplines. Through its integration of the arts, humanities and sciences, the Stanback, the only art museum with a planetarium at any of the Historically Black Colleges and Universities and one of the few in the nation, stands in the forefront of modern thinking. Cosmic Convergence: Art and Science, opening at the I.P. Stanback Museum and Planetarium in February 2010, will feature the works of Mildred Thompson (1936-2003), a prominent African American artist who worked in the media of painting, drawing, print making, sculpture, and photography. Thompson’s artwork shows the strong influences of her interest in physics, astronomy, and metaphysics as well as music and spiritualism. “My work in the visual arts is, and has always been, a continuous search for understanding. It is an expression of purpose and reflects a personal interpretation of the Universe.” Cosmic Convergence will explore the meeting of Art and Science through Mildred Thompson's work and the scientific basis of that work. The paintings and sculptures of the exhibit will be combined with astronomical images showing both the reality and interpretation of the surrounding Universe. Support for this work was provided by the NSF PAARE program to South Carolina State University under award AST-0750814.
Vadose zone flow convergence test suite
Butcher, B. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2017-06-05
Performance Assessment (PA) simulations for engineered disposal systems at the Savannah River Site involve highly contrasting materials and moisture conditions at and near saturation. These conditions cause severe convergence difficulties that typically result in unacceptable convergence or long simulation times or excessive analyst effort. Adequate convergence is usually achieved in a trial-anderror manner by applying under-relaxation to the Saturation or Pressure variable, in a series of everdecreasing RELAxation values. SRNL would like a more efficient scheme implemented inside PORFLOW to achieve flow convergence in a more reliable and efficient manner. To this end, a suite of test problems that illustrate these convergence problems is provided to facilitate diagnosis and development of an improved convergence strategy. The attached files are being transmitted to you describing the test problem and proposed resolution.
Regional Convergence and Sustainable Development in China
Fang Yang
2016-01-01
Full Text Available Based on the convergence theory of economic growth, this paper extends this concept to the human development index and carries out an empirical analysis of regional development in China between 1997 and 2006. Our research shows that the conditional convergence has been identified. Investment in fixed assets, government expenditure on education, health and infrastructure construction have positive effects on regional convergence of social development. Population weighted analysis of human development index provides support for weak convergence amongst provinces. Analysis of dynamics of regional distribution reveals the club convergence, which indicate two different convergence states. Central China is in the shade and lags behind, giving rise to the so-called “central downfall”. To solve this problem, the “Rise of Central China” Plan is necessary to promote the connection between coastal and inland regions of China and reduce the regional development gap.
A FAST CONVERGENT METHOD OF ITERATED REGULARIZATION
Huang Xiaowei; Wu Chuansheng; Wu Di
2009-01-01
This article presents a fast convergent method of iterated regularization based on the idea of Landweber iterated regularization, and a method for a-posteriori choice by the Morozov discrepancy principle and the optimum asymptotic convergence order of the regularized solution is obtained. Numerical test shows that the method of iterated regu-larization can quicken the convergence speed and reduce the calculation burden efficiently.
WEAK CONVERGENCE OF HENSTOCK INTEGRABLE SEQUENCES
LuisaDiPiazza
1994-01-01
Some relationships between pointwise and weak convergence of a sequence of Henstock integrable functions are studied, In particular it is provided an example of a sequence of Henstock integrable functions whose pointwise limit is different from the weak one. By introducing an asymptotic version of the Henstock equiintegrability notion it is given a necessary and sufficient condition in order that a pointwisely convergent sequence of Henstock integrable functions is weakly convergent to its pointwise limit.
Marital assortment and phenotypic convergence: longitudinal evidence.
Caspi, A; Herbener, E S
1993-01-01
This study provides a direct test of whether the observed similarity of spouses is due to initial assortment rather than to convergence of phenotypes. With data from three well-known longitudinal studies, phenotypic convergence is examined using both variable- and person-centered analyses. The longitudinal evidence does not support the hypothesis that couples increasingly resemble each other with time. Spouse correlations most likely reflect initial assortment at marriage and not the convergence of phenotypes.
Scalar Curvature and Intrinsic Flat Convergence
Sormani, Christina
2016-01-01
Herein we present open problems and survey examples and theorems concerning sequences of Riemannian manifolds with uniform lower bounds on scalar curvature and their limit spaces. Examples of Gromov and of Ilmanen which naturally ought to have certain limit spaces do not converge with respect to smooth or Gromov-Hausdorff convergence. Thus we focus here on the notion of Intrinsic Flat convergence, developed jointly with Wenger. This notion has been applied successfully to study sequences that arise in General Relativity. Gromov has suggested it should be applied in other settings as well. We first review intrinsic flat convergence, its properties, and its compactness theorems, before presenting the applications and the open problems.
Increasing dominance of IT in ICT convergence
Henten, Anders; Tadayoni, Reza
The aim of the paper is to examine the increasing dominance of IT companies in the converging ICT industry and, on the basis of this development, to contribute to extending the theoretical understanding of market and industry convergence in the ICT area.......The aim of the paper is to examine the increasing dominance of IT companies in the converging ICT industry and, on the basis of this development, to contribute to extending the theoretical understanding of market and industry convergence in the ICT area....
Increasing dominance of IT in ICT convergence
Henten, Anders; Tadayoni, Reza
The aim of the paper is to examine the increasing dominance of IT companies in the converging ICT industry and, on the basis of this development, to contribute to extending the theoretical understanding of market and industry convergence in the ICT area.......The aim of the paper is to examine the increasing dominance of IT companies in the converging ICT industry and, on the basis of this development, to contribute to extending the theoretical understanding of market and industry convergence in the ICT area....
Explaining convergence of oecd welfare states
Schmitt, C.; Starke, Peter
2011-01-01
Existing studies have found only limited empirical evidence of welfare state convergence. Moreover, although there are good theoretical reasons both for and against welfare state convergence, there are virtually no studies that have explicitly tested the assumed effects. We argue that the concept....... First, we show that there is very strong evidence of convergence across all categories of social expenditure when conditional factors are taken into account. Second, we demonstrate that the speed of convergence is highly driven by globalization and European Union membership and shaped by existing...... welfare state structures. © The Author(s) 2011....
Marshall Convergent Coating Development Team: An Aerospace Success Story
Lester, Carl N.
2000-01-01
The external thermal insulation systems for the Space Shuttle solid rocket boosters and the Air Force Titan IV payload fairings were in jeopardy due to EPA regulatory problems, endangering the flight status of both vehicles. The Marshall Convergent Coating (MCC-1) Development Team was formed in February 1994 to develop and implement an EPA-compliant external thermal insulation system for both systems. MCC-1 made use of a process known as Convergent Spray Technology (CST), a solventless, sprayable process that eliminated the environmentally hazardous chemicals involved with the old methods. Implemented in record time, the new insulation was so successful that it was selected for two additional flight vehicles, Boeing's Sea Launch and Delta TV. The activity also led to commercial spin-off pilot projects. The team continues today to share data between the various production sites, resolve production issues, expand the material's use, and consider potential improvements for the future.
Vidal-García, M; Keogh, J S
2015-12-01
Animals from different clades but subject to similar environments often evolve similar body shapes and physiological adaptations due to convergent evolution, but this has been rarely tested at the transcontinental level and across entire classes of animal. Australia's biome diversity, isolation and aridification history provide excellent opportunities for comparative analyses on broad-scale macroevolutionary patterns. We collected morphological and environmental data on eighty-four (98%) Australian hylid frog species and categorized them into ecotypes. Using a phylogenetic framework, we tested the hypothesis that frogs from the same ecotype display similar body shape patterns: (i) across all the Australian hylids, and (ii) through comparison with a similar previous study on 127 (97%) Australian myobatrachid species. Body size and shape variation did not follow a strong phylogenetic pattern and was not tightly correlated with environment, but there was a stronger association between morphotype and ecotype. Both arboreal and aquatic frogs had long limbs, whereas limbs of fossorial species were shorter. Other terrestrial species were convergent on the more typical frog body shape. We quantified the strength of morphological convergence at two levels: (i) between fossorial myobatrachid and hylid frogs, and (ii) in each ecomorph within the hylids. We found strong convergence within ecotypes, especially in fossorial species. Ecotypes were also reflected in physiological adaptations: both arboreal and cocooned fossorial frogs tend to have higher rates of evaporative water loss. Our results illustrate how adaptation to different ecological niches plays a crucial role in morphological evolution, boosting phenotypic diversity within a clade. Despite phylogenetic conservatism, morphological adaptation to repeatedly emerging new environments can erase the signature of ancestral morphotypes, resulting in phenotypic diversification and convergence both within and between diverse
Temporal Convergence for Knowledge Management
Christopher Phillip Martin
2008-05-01
Full Text Available Time and knowledge have tended to be conceptualised in conventional knowledge management systems as either ‘timeless’ recordings of procedures, or time-stamped records of past events and states. The concept of temporal convergence was previously developed to help apply knowledge-management theory to complex military processes such as commander’s intent, shared situation awareness, and self-synchronisation. This paper clarifies the concept and introduces several others in forming a framework to assist discussion and exploration of the types of knowledge required for complex endeavours, such as warfighting, characterised by opposition and uncertainty. The approach is grounded in a pragmatist philosophy and constructivist epistemology. Argument proceeds along mathematical lines from a basis that the types of knowledge most valuable to goal-directed agents in uncertain environments can be modelled as directed graph topologies. The framework is shown to be useful in describing and reasoning about the knowledge requirements and prerequisites for distributed decision-making through the sharing of situational knowledge and common intentions, with practical application to the planning and execution of operations. To the designers of knowledge management systems seeking to address this space, it presents a challenge that cannot be addressed merely by construction, storage, search and retrieval of documents and records pertaining to the past.
Media and democracy: false convergences
Francisco C. P. Fonseca
2006-01-01
Full Text Available This article discusses the false convergence between the role of the media in promoting democracy and political theories of democracy. With this purpose in mind, we propose critical reflections on arguments that: 1 naturalize the fact that "the news" is a commodity; b focus on the (supposedly public goals of the media, in spite of the reality that their agencies are largely private; c link these agencies to liberal- democratic values. Thus, the text attempts to show both the absence of and need for shields - personified in the theories of weights and counterbalances - against the powers that be, particularly those of the media. We point to the paradox involved in the media's role as intermediary between public and private spheres and question the degree to which the media permit fulfillment of the idea that those have control should be controlled, particularly in a world in which communication has extended its action to the planetary level. We conclude that democracy can only be made effective if democratic controls over the media are exercised; this means the creation of national and international level public information media that would be neither privately nor state owned and managed.
The long road to convergence and back. Convergence and crossmedia journalism at Dutch Newsmedia
Tameling, Klaske; Broersma, Marcel
2012-01-01
KLASKE TAMELING & MARCEL BROERSMA The long road to convergence and back. Convergence and crossmedia journalism at Dutch Newsmedia Since the end of the twentieth century, convergence and cross-media journalism are concepts that are widely used to guide the future of journalism world wide. This study
Convergence of a Linear Recursive Sequence
Tay, E. G.; Toh, T. L.; Dong, F. M.; Lee, T. Y.
2004-01-01
A necessary and sufficient condition is found for a linear recursive sequence to be convergent, no matter what initial values are given. Its limit is also obtained when the sequence is convergent. Methods from various areas of mathematics are used to obtain the results.
ON A GENERALIZED GAUSS CONVERGENCE CRITERION
ILEANA BUCUR
2015-07-01
Full Text Available In this paper we combine the well known Raabe-Duhamel, Kummer, Bertrand . . . criterions of convergence for series with positive terms and we obtain a new one which is more powerful than those cited before. Even the famous Gauss criterion,which was in fact our starting point, is a consequence of this new convergence test.
ON LACUNARY STATISTICAL CONVERGENCE OF ORDER α
Hacer SENGUL; Mikail ET
2014-01-01
In this article, we introduce the concept of lacunary statistical convergence of orderαof real number sequences and give some inclusion relations between the sets of lacu-nary statistical convergence of order α and strong Nαθ (p)-summability. Furthermore, some relations between the spaces Nαθ (p) and Sαθ are examined.
Numerical simulation of converging shock waves
Yee, Seokjune; Abe, Kanji
We can achieve the high pressure and high temperature state of gas if the shock wave converges stably. In order to check the stability of the converging shock wave, we introduce two kinds of perturbed initial conditions. The Euler equations of conservation form are integrated by using explicit Non-Muscl TVD finite difference scheme.
CONVERGENCE RATE OFDISTRIBUTIONS OF TRIMMED SUMS
QIYONGCHENG; CHENGSHIHONG
1996-01-01
The authors first derive the normal expansion of the joint density function of two orderstatistics from the uniform distribution and then, using the approximation, establish a wayto estimate the normal convergence rate for trimmed sums. For applications, the convergence rates for the intermediately trimmed sums and heavily trimmed sums are found out.
Convergence of Symmetric Diffusions on Wiener Spaces
A.Posilicano; T.S.Zhang
2004-01-01
In this paper,we study the distorted Ornstein-Uhlenbeck processes associated with given densities on an abstract Wiener space.We prove that the laws of distorted Ornstein-Uhlenbeck processes converge in total variation norm if the densities converge in Sobolev space D 1/2.
New concurrent iterative methods with monotonic convergence
Yao, Qingchuan [Michigan State Univ., East Lansing, MI (United States)
1996-12-31
This paper proposes the new concurrent iterative methods without using any derivatives for finding all zeros of polynomials simultaneously. The new methods are of monotonic convergence for both simple and multiple real-zeros of polynomials and are quadratically convergent. The corresponding accelerated concurrent iterative methods are obtained too. The new methods are good candidates for the application in solving symmetric eigenproblems.
Alassane Drabo
2010-03-01
Full Text Available This paper examines the link between health indicators, environmental variables and economic development, and th e consequences of this relationship on economic convergence for a large sample of rich and poor countries. While in economic literature income and environment are seen to have an inverted-U shaped relationship (Environment Kuznets Curve hypothesis, it is also well established that an improvement in environmental quality is positively related to health. Our study focuses on the implications of this relationship for economic convergence. In the early stage of economic development, the gain from income growth could be cancelled or mitigated by environmental degradation through populations' health (and other channels and create a vicious circle in economic activity unlike in developed countries. This in turn could slow down economic convergence. To empirically assess these issues, we proceeded to an econometric analysis through three equations: a growth equation, a health equation and an environment equation. We found that health is a channel through which environment impacts economic growth. When we take into account the effect of environment quality on economic growth, the speed of convergence tends to increase slightly. This shows that environmental quality could be considered as a constraint for economic convergence.
On the convergence of finite state mean-field games through Γ-convergence
Ferreira, Rita C.
2014-10-01
In this study, we consider the long-term convergence (trend toward an equilibrium) of finite state mean-field games using Γ-convergence. Our techniques are based on the observation that an important class of mean-field games can be viewed as the Euler-Lagrange equation of a suitable functional. Therefore, using a scaling argument, one can convert a long-term convergence problem into a Γ-convergence problem. Our results generalize previous results related to long-term convergence for finite state problems. © 2014 Elsevier Inc.
Convergence of Corporate and Information Security
Syed,; Donahue, Shannon E
2010-01-01
As physical and information security boundaries have become increasingly blurry many organizations are experiencing challenges with how to effectively and efficiently manage security within the corporate. There is no current standard or best practice offered by the security community regarding convergence; however many organizations such as the Alliance for Enterprise Security Risk Management (AESRM) offer some excellent suggestions for integrating a converged security program. This paper reports on how organizations have traditionally managed asset protection, why that is changing and how to establish convergence to optimize security value to the business within an enterprise.
Strategic business transformation through technology convergence
Agarwal, Nivedita; Brem, Alexander
2015-01-01
-time intelligence. This paper presents the case of General Electric (GE) and studies the various transitional phases and transformation dimensions that GE is experiencing, to manage this technology convergence. The evaluation of GE's experience indicates that convergence-related business transformation is nonlinear......Technology adoption is crucial for an organisation to remain competitive in the marketplace. Traditionally, two technologies - operational technology (OT) and information technology (IT) - have operated independently from one another; however, technological advancements that businesses......, and that some dimensions and stages of transformation previously thought to be relevant may not be pertinent for successful business transformations through technology convergence....
Strategic business transformation through technology convergence
Agarwal, Nivedita; Brem, Alexander
2015-01-01
-time intelligence. This paper presents the case of General Electric (GE) and studies the various transitional phases and transformation dimensions that GE is experiencing, to manage this technology convergence. The evaluation of GE's experience indicates that convergence-related business transformation is nonlinear......Technology adoption is crucial for an organisation to remain competitive in the marketplace. Traditionally, two technologies - operational technology (OT) and information technology (IT) - have operated independently from one another; however, technological advancements that businesses......, and that some dimensions and stages of transformation previously thought to be relevant may not be pertinent for successful business transformations through technology convergence....
Convergence of Attitudes among College Students
Whatley, Alice E.; Appel, Victor H.
1973-01-01
Attempts to determine whether the intersex convergence phenomenon could be applicable to the measured attitudes of collegiate samples. Both sexes seemed to be moving toward a more liberal view on issues related to marriage and the family. (Author)
Cultivate technology convergence for product innovation.
Wilkinson, J Malcolm
2006-04-01
Technologies from diverse scientific disciplines are being combined to drive innovation in medical devices. How technology convergence and innovation could be further stimulated is explored here using developments in imaging and point-of-care devices as examples.
Morphological and molecular convergences in mammalian phylogenetics.
Zou, Zhengting; Zhang, Jianzhi
2016-09-02
Phylogenetic trees reconstructed from molecular sequences are often considered more reliable than those reconstructed from morphological characters, in part because convergent evolution, which confounds phylogenetic reconstruction, is believed to be rarer for molecular sequences than for morphologies. However, neither the validity of this belief nor its underlying cause is known. Here comparing thousands of characters of each type that have been used for inferring the phylogeny of mammals, we find that on average morphological characters indeed experience much more convergences than amino acid sites, but this disparity is explained by fewer states per character rather than an intrinsically higher susceptibility to convergence for morphologies than sequences. We show by computer simulation and actual data analysis that a simple method for identifying and removing convergence-prone characters improves phylogenetic accuracy, potentially enabling, when necessary, the inclusion of morphologies and hence fossils for reliable tree inference.
Convergence of Distance Education and Conventional Learning ...
Convergence of Distance Education and Conventional Learning: Innovations ... using various blended learning media including print, ICTs, electronic platforms, ... Admittedly, the blending of offline and online learning enhances significantly ...
A Convergent Total Synthesis of Methoxatin
Hendrickson, James B.; Vries, Johannes G. de
1982-01-01
We report a convergent total synthesis of the coenzyme methoxatin (1) by linking a pyrrole subunit with an uvitonic acid derivative and oxidative photocyclization to a deoxymethoxatin triester, followed by seven refunctionalization steps to 1.
On Convergence Results for Lipschitz Pseudocontractive Mappings
Shin Min Kang
2012-01-01
Full Text Available We establish the strong convergence for the Ishikawa iteration scheme associated with Lipschitz pseudocontractive mappings in real Banach spaces. Moreover, our technique of proofs is of independent interest.
On Paranorm Zweier -Convergent Sequence Spaces
Vakeel A. Khan
2013-01-01
Full Text Available In this paper, we introduce the paranorm Zweier -convergent sequence spaces , , and , a sequence of positive real numbers. We study some topological properties, prove the decomposition theorem, and study some inclusion relations on these spaces.
Regional disparities and convergences in America
Petr Blížkovský
2012-01-01
Full Text Available This paper analyses the levels and trends of regional disparity and convergence in the two American macro-regions, NAFTA and MERCOSUR. In the case of NAFTA, 95 micro-regions were analysed (12 in Canada; 32 in Mexico; 51 states in the US. In MERCOSUR, the regions are represented by four countries (Argentina, Brazil, Paraguay and Uruguay. The analysis covers the period 2000–2008 (or rather 2000 to 2005 for Mexico. The regional disparities were calculated with the Gini coefficient based on nominal GDP, GDP per capita and GDP per capita PPS. Convergence analysis was done with the Disparity Range Coefficient (DRC, the Average Disparity Range Coefficient (ADRC, σ- convergence and β-convergence. The results of regional disparity were as follows. Based on the nominal GDP, it was at high levels in both macro-regions, with a Gini coefficient above 0.55. With the disparities calculated on GDP per capita, the level of regional disparity in both macro-regions was lower at 0.36 in NAFTA and 0.28 in MERCOSUR in 2000. Based on GDP per capita in PPP, the levels were lower than based on the GDP per capita analysis starting at 0.31 in NAFTA and 0.16 in MERCOSUR. The disparities further decreased by half in NAFTA while slightly increasing in MERSCOSUR. The convergence analysis results based on the DRC analysis showed that neither NAFTA nor MERCOSUR regions converged. The speed of divergence varied significantly. The disparities among the richest and poorest regions in GDP per capita increased 6.26 times more than the average GDP per capita in PPP in NAFTA as a whole. It was only 0.52 in MERCOSUR. The ADRC analysis also resulted in divergence trends for both macro-regions but with lower rates. Convergence calculated with the σ- convergence analysis confirmed that both macro-regions diverged. The divergence rate for NAFTA was 1.41% and for MERCOSUR 0.74. Calculated with the β-convergence analysis, the NAFTA region showed a status quo (convergence of 0.01% and a
Convergence of random zeros on complex manifolds
Bernard SHIFFMAN
2008-01-01
We show that the zeros of random sequences of Gaussian systems of polynomials of in-creasing degree almost surely converge to the expected limit distribution under very general hypotheses.In particular,the normalized distribution of zeros of systems of m polynomials of degree N,orthonor-malized on a regular compact set K(∪)Cm,almost surely converge to the equilibrium measure on K as N →∞.
Convergence of random zeros on complex manifolds
Bernard; SHIFFMAN
2008-01-01
We show that the zeros of random sequences of Gaussian systems of polynomials of in- creasing degree almost surely converge to the expected limit distribution under very general hypotheses. In particular,the normalized distribution of zeros of systems of m polynomials of degree N,orthonor- malized on a regular compact set K(?)C~m,almost surely converge to the equilibrium measure on K as N→∞.
International Convergence on Geoscience Cyberinfrastructure
Allison, M. L.; Atkinson, R.; Arctur, D. K.; Cox, S.; Jackson, I.; Nativi, S.; Wyborn, L. A.
2012-04-01
There is growing international consensus on addressing the challenges to cyber(e)-infrastructure for the geosciences. These challenges include: Creating common standards and protocols; Engaging the vast number of distributed data resources; Establishing practices for recognition of and respect for intellectual property; Developing simple data and resource discovery and access systems; Building mechanisms to encourage development of web service tools and workflows for data analysis; Brokering the diverse disciplinary service buses; Creating sustainable business models for maintenance and evolution of information resources; Integrating the data management life-cycle into the practice of science. Efforts around the world are converging towards de facto creation of an integrated global digital data network for the geosciences based on common standards and protocols for data discovery and access, and a shared vision of distributed, web-based, open source interoperable data access and integration. Commonalities include use of Open Geospatial Consortium (OGC) and ISO specifications and standardized data interchange mechanisms. For multidisciplinarity, mediation, adaptation, and profiling services have been successfully introduced to leverage the geosciences standards which are commonly used by the different geoscience communities -introducing a brokering approach which extends the basic SOA archetype. Principal challenges are less technical than cultural, social, and organizational. Before we can make data interoperable, we must make people interoperable. These challenges are being met by increased coordination of development activities (technical, organizational, social) among leaders and practitioners in national and international efforts across the geosciences to foster commonalities across disparate networks. In doing so, we will 1) leverage and share resources, and developments, 2) facilitate and enhance emerging technical and structural advances, 3) promote
Welfare state: Convergence: Downward versus upward
Josifidis Kosta
2010-01-01
Full Text Available The aim of this paper is to contribute, in the theoretical and empirical sense, to better understanding the challenges of the EU welfare regimes and how particular regimes react on them. Despite significant differences among the EU welfare regimes, it is real to expect that they will converge because of the common challenges confronting them. In this paper, using the model of sigma and beta convergence, we are trying to predict the possible direction of convergence in the sense that Europe will go toward to more or less generosity or in other words it will converge downward or upward. The downward convergence means the strengthen competition among existing welfare regimes, in order to maintain and/or attract capital, that could reduce the social spending generosity. On the other hand, the upward convergence above involves the strengthening of coordination among existing welfare regimes according to the values of solidarity and social justice, which characterise not only the most developed EU countries but also the supranational European social model. .
Fixing convergence of Gaussian belief propagation
Johnson, Jason K [Los Alamos National Laboratory; Bickson, Danny [IBM RESEARCH LAB; Dolev, Danny [HEBREW UNIV
2009-01-01
Gaussian belief propagation (GaBP) is an iterative message-passing algorithm for inference in Gaussian graphical models. It is known that when GaBP converges it converges to the correct MAP estimate of the Gaussian random vector and simple sufficient conditions for its convergence have been established. In this paper we develop a double-loop algorithm for forcing convergence of GaBP. Our method computes the correct MAP estimate even in cases where standard GaBP would not have converged. We further extend this construction to compute least-squares solutions of over-constrained linear systems. We believe that our construction has numerous applications, since the GaBP algorithm is linked to solution of linear systems of equations, which is a fundamental problem in computer science and engineering. As a case study, we discuss the linear detection problem. We show that using our new construction, we are able to force convergence of Montanari's linear detection algorithm, in cases where it would originally fail. As a consequence, we are able to increase significantly the number of users that can transmit concurrently.
Auto convergence for stereoscopic 3D cameras
Zhang, Buyue; Kothandaraman, Sreenivas; Batur, Aziz Umit
2012-03-01
Viewing comfort is an important concern for 3-D capable consumer electronics such as 3-D cameras and TVs. Consumer generated content is typically viewed at a close distance which makes the vergence-accommodation conflict particularly pronounced, causing discomfort and eye fatigue. In this paper, we present a Stereo Auto Convergence (SAC) algorithm for consumer 3-D cameras that reduces the vergence-accommodation conflict on the 3-D display by adjusting the depth of the scene automatically. Our algorithm processes stereo video in realtime and shifts each stereo frame horizontally by an appropriate amount to converge on the chosen object in that frame. The algorithm starts by estimating disparities between the left and right image pairs using correlations of the vertical projections of the image data. The estimated disparities are then analyzed by the algorithm to select a point of convergence. The current and target disparities of the chosen convergence point determines how much horizontal shift is needed. A disparity safety check is then performed to determine whether or not the maximum and minimum disparity limits would be exceeded after auto convergence. If the limits would be exceeded, further adjustments are made to satisfy the safety limits. Finally, desired convergence is achieved by shifting the left and the right frames accordingly. Our algorithm runs real-time at 30 fps on a TI OMAP4 processor. It is tested using an OMAP4 embedded prototype stereo 3-D camera. It significantly improves 3-D viewing comfort.
Convergence of functional areas in information operations
Brett van Niekerk
2015-02-01
Full Text Available Background: Contemporary technology and its rapid rise to a ubiquitous nature are affecting the way in which technology is used. This holds implications for military information operations and information warfare concepts as the previously separate functional areas are increasingly overlapping due to the increased convergence of information technology.Objective: The aim of the article is to illustrate the convergence of the functional areas of information operations through the use of reported examples and descriptive models. Methods: A qualitative review and analysis of practitioner documents, academic publications, and other reports is conducted. The diverse views of this phenomenon are contrasted and discussed. The possible implications of the convergence and possible management techniques are proposed and discussed. Results: There is strong opinion that the domains are not converging, however practice shows that there is an increasing overlap of operational considerations and organisational structure. Conclusion: It is concluded that the domains are not converging, but the operations and management of the information operations functional areas may converge, and this has an impact across all functional areas that needs to be taken into consideration.
Qunying Wu
2016-06-01
Full Text Available Abstract In this paper, we study the complete convergence and complete moment convergence for negatively associated sequences of random variables with E X = 0 $\\mathbb{E}X=0$ , E exp ( ln α | X | 1 $\\alpha>1$ . As a result, we extend some complete convergence and complete moment convergence theorems for independent random variables to the case of negatively associated random variables without necessarily imposing any extra conditions. Our results generalize corresponding results obtained by Gut and Stadtmüller (Stat. Probab. Lett. 81:1486-1492, 2011 and Qiu and Chen (Stat. Probab. Lett. 91:76-82, 2014.
Possibilities for global governance of converging technologies
Roco, Mihail C.
2008-01-01
The convergence of nanotechnology, modern biology, the digital revolution and cognitive sciences will bring about tremendous improvements in transformative tools, generate new products and services, enable opportunities to meet and enhance human potential and social achievements, and in time reshape societal relationships. This paper focuses on the progress made in governance of such converging, emerging technologies and suggests possibilities for a global approach. Specifically, this paper suggests creating a multidisciplinary forum or a consultative coordinating group with members from various countries to address globally governance of converging, emerging technologies. The proposed framework for governance of converging technologies calls for four key functions: supporting the transformative impact of the new technologies; advancing responsible development that includes health, safety and ethical concerns; encouraging national and global partnerships; and establishing commitments to long-term planning and investments centered on human development. Principles of good governance guiding these functions include participation of all those who are forging or affected by the new technologies, transparency of governance strategies, responsibility of each participating stakeholder, and effective strategic planning. Introduction and management of converging technologies must be done with respect for immediate concerns, such as privacy, access to medical advancements, and potential human health effects. At the same time, introduction and management should also be done with respect for longer-term concerns, such as preserving human integrity, dignity and welfare. The suggested governance functions apply to four levels of governance: (a) adapting existing regulations and organizations; (b) establishing new programs, regulations and organizations specifically to handle converging technologies; (c) building capacity for addressing these issues into national policies and
EVALUATION OF CONVERGENT SPRAY TECHNOLOGYTM SPRAY PROCESS FOR ROOF COATING APPLICATION
The overall goal of this project was to demonstrate the feasibility of Convergent Spray TechnologyTM for the roofing industry. This was accomplished by producing an environmentally compliant coating utilizing recycled materials, a CSTTM spray process portable application cart, a...
Regional disparities and convergences in Asia
Petr Blížkovský
2012-01-01
Full Text Available This paper analyses the disparity and convergence between the 10 and 11 countries of ASEAN and the Commonwealth of Independent States (CIS respectively and the 31 sub-national regions (provinces in China.The regional disparity levels and trends were analysed using the Gini coefficient between the regions (nominal GDP, GDP per capita and GDP per capita in Purchasing Parity Power, PPP. The convergence analysis was evaluated using the Disparity Range Coefficient (DRC, the Average Disparity Range Coefficient (ADRC, and the σ- and b-convergence. The time period covered was 2000–2008 (ASEAN and CIS and 2000–2006 (China.The results show a relatively high regional disparity between the Asian macro-regions of ASEAN and CIS and much lower disparities between the China sub-regions. The disparities were highest if based on the nominal GDP and lower if based on the DGP per capita. The GDP per capita was lower, between 0.30 to 0.4 for the CIS and China, and around 0.7 in ASEAN. The convergence analysis showed mixed results. Based on the DRC analysis, none of the Asian macro-regions converged. All three macro-regions diverged 1.4 to 12.68 times quicker than the average macro-regional GDP per capita grew, ASEAN being at the divergence top and China at the bottom. Based on the ADRC analysis, all macro-regions also proved to diverge. However, the divergence rates were much lower. For macro-regions China and CIS, the divergence was slower than macro-regional growth, thus their divergence was moderate. On the other side, if the macro-region was calculated using the σ-convergence analysis, the converging macro-regions were ASEAN and China, with 2.13% and 0.47% respectively. CIS was diverging at the speed of 1.25% per year. Based on b-convergence, ASEAN and China were converging (1.54% and 1.32%, and a slow divergence trend was registered for CIS, 1.01%.
Noise can speed convergence in Markov chains.
Franzke, Brandon; Kosko, Bart
2011-10-01
A new theorem shows that noise can speed convergence to equilibrium in discrete finite-state Markov chains. The noise applies to the state density and helps the Markov chain explore improbable regions of the state space. The theorem ensures that a stochastic-resonance noise benefit exists for states that obey a vector-norm inequality. Such noise leads to faster convergence because the noise reduces the norm components. A corollary shows that a noise benefit still occurs if the system states obey an alternate norm inequality. This leads to a noise-benefit algorithm that requires knowledge of the steady state. An alternative blind algorithm uses only past state information to achieve a weaker noise benefit. Simulations illustrate the predicted noise benefits in three well-known Markov models. The first model is a two-parameter Ehrenfest diffusion model that shows how noise benefits can occur in the class of birth-death processes. The second model is a Wright-Fisher model of genotype drift in population genetics. The third model is a chemical reaction network of zeolite crystallization. A fourth simulation shows a convergence rate increase of 64% for states that satisfy the theorem and an increase of 53% for states that satisfy the corollary. A final simulation shows that even suboptimal noise can speed convergence if the noise applies over successive time cycles. Noise benefits tend to be sharpest in Markov models that do not converge quickly and that do not have strong absorbing states.
Gene Acquisition Convergence between Entomopoxviruses and Baculoviruses
Julien Thézé
2015-04-01
Full Text Available Organisms from diverse phylogenetic origins can thrive within the same ecological niches. They might be induced to evolve convergent adaptations in response to a similar landscape of selective pressures. Their genomes should bear the signature of this process. The study of unrelated virus lineages infecting the same host panels guarantees a clear identification of phyletically independent convergent adaptation. Here, we investigate the evolutionary history of genes in the accessory genome shared by unrelated insect large dsDNA viruses: the entomopoxviruses (EPVs, Poxviridae and the baculoviruses (BVs. EPVs and BVs have overlapping ecological niches and have independently evolved similar infection processes. They are, in theory, subjected to the same selective pressures from their host’s immune responses. Their accessory genomes might, therefore, bear analogous genomic signatures of convergent adaption and could point out key genomic mechanisms of adaptation hitherto undetected in viruses. We uncovered 32 homologous, yet independent acquisitions of genes originating from insect hosts, different eukaryotes, bacteria and viruses. We showed different evolutionary levels of gene acquisition convergence in these viruses, underlining a continuous evolutionary process. We found both recent and ancient gene acquisitions possibly involved to the adaptation to both specific and distantly related hosts. Multidirectional and multipartite gene exchange networks appear to constantly drive exogenous gene assimilations, bringing key adaptive innovations and shaping the life histories of large DNA viruses. This evolutionary process might lead to genome level adaptive convergence.
Yongfeng Wu
2014-01-01
Full Text Available The authors first present a Rosenthal inequality for sequence of extended negatively dependent (END random variables. By means of the Rosenthal inequality, the authors obtain some complete moment convergence and mean convergence results for arrays of rowwise END random variables. The results in this paper extend and improve the corresponding theorems by Hu and Taylor (1997.
Societal response to nanotechnology: converging technologies–converging societal response research?
Ronteltap, A.; Fischer, A.R.H.; Tobi, H.
2011-01-01
Nanotechnology is an emerging technology particularly vulnerable to societal unrest, which may hinder its further development. With the increasing convergence of several technological domains in the field of nanotechnology, so too could convergence of social science methods help to anticipate societ
Regional Convergence in Knowledge-based Economy
Maryam Fattahi
2011-01-01
Full Text Available Nowadays, the world economies are rapidly moving towards being more Knowledge-based Economy (KBE and supporting the force of knowledge as a vital component of economic growth. This recent acceleration in the transition to Knowledge-based Economy in the world, has affected regional economic performance. In this paper, we surveyed the regional convergence in Knowledge-based Economy for selected Asia and pacific countries. We used a growth model in Barro and Sala-i-Martin framework (1995 for the period of 1995-2009. It includes a panel data set consisting of the annual growth rate of GDP per capita for selected Asia and pacific countries and a group of indicators that define the situation of Knowledge-based Economy in countries. The empirical results indicate that the absolute and the conditional convergence are not rejected for selected countries. The investigation on robustness of the model results confirms the existence of regional convergence for studied countries.
Convergence Time Evaluation of Algorithms in MANETs
Patil, Annapurna P; Chunhaviriyakul, Krittaya
2009-01-01
Since the advent of wireless communication, the need for mobile ad hoc networks has been growing exponentially. This has opened up a Pandoras Box of algorithms for dealing with mobile ad hoc networks, or MANETs, as they are generally referred to. Most attempts made at evaluating these algorithms so far have focused on parameters such as throughput, packet delivery ratio, overhead etc. An analysis of the convergence times of these algorithms is still an open issue. The work carried out fills this gap by evaluating the algorithms on the basis of convergence time. Algorithms for MANETs can be classified into three categories: reactive, proactive, and hybrid protocols. In this project, we compare the convergence times of representative algorithms in each category, namely Ad hoc On Demand Distance Vector (AODV) reactive, Destination Sequence Distance Vector protocol (DSDV) proactive, and Temporally Ordered Routing Algorithm (TORA) hybrid. The algorithm performances are compared by simulating them in ns2. Tcl is us...
Divergence and Convergence in Education and Work
Are the educational systems in Europe becoming more similar or more different? This book deals with the issue ofdivergence and convergence in relation to systems, learning environments, and learners in vocational educational training (VET). 18 VET researchers from eight countries contribute...... to the examination of 'divergence and convergence' at three levels: At the national level this volume deals with the following questions: What are the consequences of the European policies that aim at converging the VET systems in Europe? What is the impact of globalization on the national systems? At the level...... of institutions the central issue concerns the relation between learning environments. What is the coherence between school-based education and learning in the work-place, and how can they connect? Finally at the third level of the learners and their identities the focus is on the role of vocational educational...
Convergence of Hybrid Space Mapping Algorithms
Madsen, Kaj; Søndergaard, Jacob
2004-01-01
\\$mapsto \\$\\backslash\\$dR\\$ is convex and \\$f: \\$\\backslash\\$dR\\^n \\$\\backslash\\$mapsto \\$\\backslash\\$dR\\^m\\$ is smooth. Experience indicates that the combined method maintains the initial efficiency of the space mapping technique. We prove that the global convergence property of the classical technique is also......The space mapping technique is intended for optimization of engineering models which involve very expensive function evaluations. It may be considered a preprocessing method which often provides a very efficient initial phase of an optimization procedure. However, the ultimate rate of convergence...... may be poor, or the method may even fail to converge to a stationary point. We consider a convex combination of the space mapping technique with a classical optimization technique. The function to be optimized has the form \\$H \\$\\backslash\\$circ f\\$ where \\$H: \\$\\backslash\\$dR\\^m \\$\\backslash...
International Accounting Convergences Related to EU Admitance
Niculae Feleaga
2006-05-01
Full Text Available Starting from January 1, 2005, member countries of the European Union began the obligatory or optional application of the international standards IAS/IFRS for consolidated accounts, what means a revolution in financial reporting of the enterprises. In regards to the individual accounts (generally based on the national book-keeping standards these will converge gradually to referential international book-keeper on short and medium term. At the world level the process which dominates the accounting systems is the convergence between american and international reference system, followed immediatly more or less by the convergence between national accounting systems and the international one. Where Romania and its specialists are situated confronting this process? A reflection subject which finalises this article.
Convergence of coupled cluster perturbation theory
Eriksen, Janus Juul; Matthews, Devin A; Jørgensen, Poul; Olsen, Jeppe
2016-01-01
The convergence of a recently proposed coupled cluster (CC) family of perturbation series [Eriksen et al., J. Chem. Phys. 140, 064108 (2014)], in which the energetic difference between a parent and a target CC model is expanded in orders of the M{\\o}ller-Plesset (MP) fluctuation potential, is investigated for four prototypical closed-shell systems (Ne, singlet methylene, distorted HF, and the fluoride anion) in standard and augmented basis sets. In these investigations, energy corrections of the various series have been calculated to high orders and their convergence radii determined by probing for possible front- and back-door intruder states. In summary, we conclude how it is primarily the choice of target state, and not the choice of parent state, which ultimately governs the convergence behavior of a given series. For example, restricting the target state to, say, triple or quadruple excitations might remove intruders present in series that target the full configuration interaction (FCI) limit, such as th...
EVALUATION OF ECONOMIC CONVERGENCE IN ROMANIA
CUCO PAULA – ROXANA,
2016-10-01
Full Text Available This article aims to highlight the process of regional convergence (regarding income wage per capita or on the contrary, the process of regional divergence, between the 42 counties as reference territorial units in Romania, within the period 2005-2014. In the econometric analyze, the models that were developed had the aim to assess the role of macroeconomic determinants on the average net income per capita, exactly the possibility of a more dynamic growth of wages in poorer counties. The results showed a clear trend towards wage convergence, under the impact of multidimensional factors of influence. Our findings confirm the literature on regional convergence, pointing out the importance of economic development level, quality of human capital, technical progress and intensity of innovation activity, improving labor market integration and even a dynamic entrepreneurial activity.
International Accounting Convergences Related to EU Admitance
Liliana Feleaga
2006-03-01
Full Text Available Starting from January 1, 2005, member countries of the European Union began the obligatory or optional application of the international standards IAS/IFRS for consolidated accounts, what means a revolution in financial reporting of the enterprises. In regards to the individual accounts (generally based on the national book-keeping standards these will converge gradually to referential international book-keeper on short and medium term. At the world level the process which dominates the accounting systems is the convergence between american and international reference system, followed immediatly more or less by the convergence between national accounting systems and the international one. Where Romania and its specialists are situated confronting this process? A reflection subject which finalises this article.
Core Backbone Convergence Mechanisms and Microloops Analysis
Abdelali Ala
2012-07-01
Full Text Available In this article we study approaches that can be used to minimise the convergence time, we also make a focus on microloops phenomenon, analysis and means to mitigate them. The convergence time reflects the time required by a network to react to a failure of a link or a router failure itself. When all nodes (routers have updated their respective routing and forwarding databases, we can say the network has converged. This study will help in building real-time and resilient network infrastructure, the goal is to make any evenement in the core network, as transparent as possible to any sensitive and real-time flows. This study is also, a deepening of earlier works presented in [10] and [11].
Convergence of Hybrid Space Mapping Algorithms
Madsen, Kaj; Søndergaard, Jacob
2004-01-01
\\$mapsto \\$\\backslash\\$dR\\$ is convex and \\$f: \\$\\backslash\\$dR\\^n \\$\\backslash\\$mapsto \\$\\backslash\\$dR\\^m\\$ is smooth. Experience indicates that the combined method maintains the initial efficiency of the space mapping technique. We prove that the global convergence property of the classical technique is also......The space mapping technique is intended for optimization of engineering models which involve very expensive function evaluations. It may be considered a preprocessing method which often provides a very efficient initial phase of an optimization procedure. However, the ultimate rate of convergence...... may be poor, or the method may even fail to converge to a stationary point. We consider a convex combination of the space mapping technique with a classical optimization technique. The function to be optimized has the form \\$H \\$\\backslash\\$circ f\\$ where \\$H: \\$\\backslash\\$dR\\^m \\$\\backslash...
Plurality or convergence in sustainability reporting standards?
Nadia Albu
2013-11-01
Full Text Available Over the last years an increasing number of companies issued Corporate Social Responsibility (CSR or Sustainability Reports to complement their traditional financial reporting. Companies use various sustainability reporting standards or develop their own reporting frameworks starting from the existing ones. This variation of practices pointed out by empirical research raises questions about the quality and comparability of sustainability reporting, its role in the sustainable development, and also about the suitability of accepting the plurality of reporting frameworks or the need for convergence. This study aims to investigate the issues of plurality and convergence in sustainability reporting standards, by mobilizing the discourses on regulation and the case of a group of companies in the IT industry in order to shed some light on the current challenges in this area. We frame a discussion on the opportunities and pitfalls of convergence in sustainability reporting regulations and contribute to a better understanding of this issue by academics, preparers, users and standard setters
Science and technology convergence: with emphasis for nanotechnology-inspired convergence
Bainbridge, William S.; Roco, Mihail C.
2016-07-01
Convergence offers a new universe of discovery, innovation, and application opportunities through specific theories, principles, and methods to be implemented in research, education, production, and other societal activities. Using a holistic approach with shared goals, convergence seeks to transcend existing human limitations to achieve improved conditions for work, learning, aging, physical, and cognitive wellness. This paper outlines ten key theories that offer complementary perspectives on this complex dynamic. Principles and methods are proposed to facilitate and enhance science and technology convergence. Several convergence success stories in the first part of the 21st century—including nanotechnology and other emerging technologies—are discussed in parallel with case studies focused on the future. The formulation of relevant theories, principles, and methods aims at establishing the convergence science.
Convergence of Wavelet Expansions in the Orlicz Space
Chang Mei TAN
2011-01-01
In this paper we study the convergence in norm and pointwise convergence of wavelet expansion in the Orlicz spaces, and prove that, under certain conditions on the wavelet, the wavelet expansion converges in the Orlicz-norm and also converges almost everywhere.
Specialisation and Convergence in European Regions
Enrico Marelli
2007-09-01
Full Text Available The purpose of this paper was to analyze specialization and convergence of European countries and regions, within the framework of integration in the EU. This is important not only for long-term real convergence processes, but also for a proper functioning of the monetary union (in the line of research on the OCA's criteria, asymmetry of shocks and synchronization of business cycles. The position of new member states is particularly delicate, also considering the forthcoming adoption of the euro by some of them. As indicated by the EU Treaty, economic growth should be balanced with economic and social cohesion that includes a careful consideration of regional disparities. Our empirical investigation focuses on the regions of EU25, further broken up into other relevant groupings (EU15, EMU, and the new members' EU10 group, over the period from 1980 (or 1990 for EU10 to 2005. This paper considers a rather fine regional disaggregation (NUTS-2 level, counting 250 regions. The analysis of different indices of specialisation point to a prevalent increase of homogeneity of sector structures across European regions, although in some cases (especially in the industrial sector and in some services specialisation has increased. For convergence, a sigma convergence's analysis confirms a reduction of disparities, both at a country and regional level. However, a trade-off between fast national growth and internal distribution has emerged in the early stages of development, as in the case of new members. Moreover, beta convergence has also been established - regarding per capita income, employment and productivity - for almost all territorial aggregates (excluding the new members since 1999. The addition of structural variables, following a beta-conditional approach, indicates a positive role for services and a negative impact of agriculture. Finally, some preliminary results have been obtained by the innovative inclusion of specialisation indices within
Moen, Daniel S; Morlon, Hélène; Wiens, John J
2016-01-01
Striking evolutionary convergence can lead to similar sets of species in different locations, such as in cichlid fishes and Anolis lizards, and suggests that evolution can be repeatable and predictable across clades. Yet, most examples of convergence involve relatively small temporal and/or spatial scales. Some authors have speculated that at larger scales (e.g., across continents), differing evolutionary histories will prevent convergence. However, few studies have compared the contrasting roles of convergence and history, and none have done so at large scales. Here we develop a two-part approach to test the scale over which convergence can occur, comparing the relative importance of convergence and history in macroevolution using phylogenetic models of adaptive evolution. We apply this approach to data from morphology, ecology, and phylogeny from 167 species of anuran amphibians (frogs) from 10 local sites across the world, spanning ~160 myr of evolution. Mapping ecology on the phylogeny revealed that similar microhabitat specialists (e.g., aquatic, arboreal) have evolved repeatedly across clades and regions, producing many evolutionary replicates for testing for morphological convergence. By comparing morphological optima for clades and microhabitat types (our first test), we find that convergence associated with microhabitat use dominates frog morphological evolution, producing recurrent ecomorphs that together encompass all sampled species in each community in each region. However, our second test, which examines whether and how much species differ from their inferred optima, shows that convergence is incomplete: that is, phenotypes of most species are still somewhat distant from the estimated optimum for each microhabitat, seemingly because of insufficient time for more complete adaptation (an effect of history). Yet, these effects of history are related to past ecologies, and not clade membership. Overall, our study elucidates the dominant drivers of
Large Field Cutoffs Make Perturbative Series Converge
Meurice, Y
2002-01-01
For lambda phi^4 problems, convergent perturbative series can be obtained by cutting off the large field configurations. The modified series converge to values exponentially close to the exact ones. For lambda larger than some critical value, the method outperforms Pade approximants and Borel summations. We discuss some aspects of the semi-classical methods used to calculate the modified Feynman rules and estimate the error associated with the procedure. We provide a simple numerical example where the procedure works despite the fact that the Borel sum has singularities on the positive real axis.
Large field cutoffs make perturbative series converge
Meurice, Yannick
2002-03-01
For λφ 4 problems, convergent perturbative series can be obtained by cutting off the large field configurations. The modified series converge to values exponentially close to the exact ones. For λ larger than some critical value, the method outperforms Padé approximants and Borel summations. We discuss some aspects of the semi-classical methods used to calculate the modified Feynman rules and estimate the error associated with the procedure. We provide a simple numerical example where the procedure works despite the fact that the Borel sum has singularities on the positive real axis.
ON CONVERGENCE OF WAVELET PACKET EXPANSIONS
Morten Nielsen
2002-01-01
It is well known that the-Walsh-Fourier expansion of a function from the block space ([0, 1 ) ), 1 ＜q≤∞, converges pointwise a.e. We prove that the same result is true for the expansion of a function from in certain periodixed smooth periodic non-stationary wavelet packets bases based on the Haar filters. We also consider wavelet packets based on the Shannon filters and show that the expansion of Lp-functions, 1＜p＜∞, converges in norm and pointwise almost everywhere.
ON THE CONVERGENCE OF COMPLEX SOR
无
2001-01-01
In order to solve the linear algebraic system AX=b in complex domain, where A is a weakly cyclic of index p= 3 matrix (p-cyclic matrix), the convergence properties of SOR are stud ied in the paper. In section 1, we give some definitions. In section 2, the necessary conditions for convergent complex SOR are given moreover the necessary and su fficient conditions in some special situations are also presented. In section 3, we expand the techniques applied by R.S. Varga et al., and it is established that the results of R.S. Varga et. al. are special cases of our work.
Extended Global Convergence Framework for Unconstrained Optimization
(A)rpád B(U)RMEN; Franc BRATKOVI(C); Janez PUHAN; Iztok FAJFAR; Tadej TUMA
2004-01-01
An extension of the global convergence framework for unconstrained derivative-free optimization methods is presented. The extension makes it possible for the framework to include optimization methods with varying cardinality of the ordered direction set. Grid-based search methods are shown to be a special case of the more general extended global convergence framework. Furthermore,the required properties of the sequence of ordered direction sets listed in the definition of grid-based methods are re]axed and simplified by removing the requirement of structural equivalence.
FDI, Human Capital and Income Convergence
Völlmecke, Dominik; Jindra, Björn; Marek, Philipp
2016-01-01
This study examines income convergence in regional GDP per capita for a sample of 269 regions within the European Union (EU) between 2003 and 2010. We use an endogenous broad capital model based on foreign direct investment (FDI) induced agglomeration economies and human capital. By applying...... a Markov chain approach to a new dataset that exploits micro-aggregated sub-national FDI statistics, the analysis provides insights into regional income growth dynamics within the EU. Our results indicate a weak process of overall income convergence across EU regions. This does not apply to the dynamics...
On Conditions for Convergence to Consensus
Lorenz, Jan
2008-01-01
A new theorem on conditions for convergence to consensus of a multiagent time-dependent time-discrete dynamical system is presented. The theorem is build up on the notion of averaging maps. We compare this theorem to Moreau's Theorem and his proposed set-valued Lyapunov theory (IEEE Transactions on Automatic Control, vol. 50, no. 2, 2005). We give examples that point out differences of approaches including examples where Moreau's theorem is not applicable but ours is. Further on, we give examples that demonstrate that the theory of convergence to consensus is still not complete.
CONVERGENCE OF REAL WAGES IN RURAL AREAS IN POLAND
Piotr Adamczyk
2016-01-01
The article concerns the spatial diversity of rural areas. The aim of the article is to evaluate whether the process of convergence of real wages in rural areas in Poland can be observed. The author focuses on two concepts of convergence: absolute (unconditional) beta convergence and sigma convergence. The analysis regards rural districts at NUTS-4 level for 2002–2014. It was stated that rural areas in Poland became similar (converge) in terms of real wages what can help reducing the di...
Testing for convergence from the micro-level
Giorgio Fazio; Davide Piacentino
2011-01-01
In the growth literature, researchers are typically concerned with macro convergence. However, to the extent that macro dynamics result from the underlying microeconomic relations, convergence should also be investigated at the micro-level. In this paper, we suggest an approach that allows exploiting large micro panels to test for convergence. Compared to the traditional convergence analysis, this approach allows obtaining, at the same time, β and σ like convergence parameters for both the mi...
Professional Communication and Translation in Convergence
Gnecci, Marusca; Maylath, Bruce; Mousten, Birthe;
2008-01-01
As translation of technical documents becomes commonplace, and as translation becomes more automated, the roles of translator and technical communicator appear to be converging. This paper examines the trend revealed from recent surveys, and it suggests further research to determine if the trend ...... is likely to continue. The paper also provides recommendations for academic programs interested in adjusting to the trend....
Convergence of some asynchronous nonlinear multisplitting methods
Szyld, Daniel B.; Xu, Jian-Jun
2000-09-01
Frommer's nonlinear multisplitting methods for solving nonlinear systems of equations are extended to the asynchronous setting. Block methods are extended to include overlap as well. Several specific cases are discussed. Sufficient conditions to guarantee their local convergence are given. A numerical example is presented illustrating the performance of the new approach.
China's Macroeconomic Development: Stages and Nonlinear Convergence
Pingyao Lai
2006-01-01
The central theme of this paper is that China's macroeconomic development can be divided into three distinct stages with significant trend changes. Market-oriented reform and opening to the outside world provide main driving forces for the convergence. However, the gradual reform and some inappropriate policies have caused serious ups and downs in China's macroeconomic performance.
Convergence of zeta functions of graphs
Clair, Bryan; Mokhtari-Sharghi, Shahriar
2000-01-01
The $L^2$-zeta function of an infinite graph Y (defined previously in a ball around zero) has an analytic extension. For a tower of finite graphs covered by Y, the normalized zeta functions of the finite graphs converge to the $L^2$-zeta function of Y.
Culture and Social Psychology: Converging Perspectives
Dimaggio, Paul; Markus, Hazel Rose
2010-01-01
Views of culture in psychology and sociology have converged markedly in the past two decades. Both have rejected what Adams and Markus (2004) refer to as the "entity" conception of culture--the view that culture is coherent, stable, and located in the heads of collectivities' members--in favor of more supple and dynamic constructs. Culture, in…
1-Convergence of Complex Double Fourier Series
Kulwinder Kaur; S S Bhatia; Babu Ram
2003-11-01
It is proved that the complex double Fourier series of an integrable function (, ) with coefficients {} satisfying certain conditions, will converge in 1-norm. The conditions used here are the combinations of Tauberian condition of Hardy–Karamata kind and its limiting case. This paper extends the result of Bray [1] to complex double Fourier series.
Phonological Convergence in a Contracting Language Variety
Bullock, Barbara E.; Gerfen, Chip
2004-01-01
Most work investigating the role of convergence in situations of language attrition has focused on the morpho-syntactic restructuring of the dying language variety. A central concern of such research has been untangling the factors driving the restructuring with an eye towards establishing whether the changes observed are best viewed as externally…
Two convergence results for continuous descent methods
Simeon Reich
2003-03-01
Full Text Available We consider continuous descent methods for the minimization of convex functionals defined on general Banach space. We establish two convergence results for methods which are generated by regular vector fields. Since the complement of the set of regular vector fields is $sigma$-porous, we conclude that our results apply to most vector fields in the sense of Baire's categories.
Convergence of approximations of monotone gradient systems
Zambotti, Lorenzo
2006-01-01
We consider stochastic differential equations in a Hilbert space, perturbed by the gradient of a convex potential. We investigate the problem of convergence of a sequence of such processes. We propose applications of this method to reflecting O.U. processes in infinite dimension, to stochastic partial differential equations with reflection of Cahn-Hilliard type and to interface models.
Strong Ideal Convergence in Probabilistic Metric Spaces
Celaleddin Şençimen; Serpil Pehlivan
2009-06-01
In the present paper we introduce the concepts of strongly ideal convergent sequence and strong ideal Cauchy sequence in a probabilistic metric (PM) space endowed with the strong topology, and establish some basic facts. Next, we define the strong ideal limit points and the strong ideal cluster points of a sequence in this space and investigate some properties of these concepts.
Strong convergence results for hemivariational inequalities
LIU Zhenhai; ZOU Jiezhong
2006-01-01
The purpose of this paper is to study a regularization method of solutions of ill-posed problems involving hemivariational inequalities in Banach spaces. Under the assumption that the hemivariational inequality is solvable, a strongly convergent approximation procedure is designed by means of the so-called Browder-Tikhonov regularization method. Our results generalize and extend the previously known theorems.
Convergent evolution in plant specialized metabolism.
Pichersky, Eran; Lewinsohn, Efraim
2011-01-01
Plants synthesize a multitude of compounds that contribute to adaptation to their ecological niches. Such compounds serve as attractants of other living organisms beneficial to the plants or as defense against other biotic as well as abiotic agents. Selection for increased fitness, a never-ending process, has resulted in each plant lineage synthesizing a distinct set of specialized metabolites appropriate for its environment. The total number of specialized metabolites found in the plant kingdom far exceeds the capacity of any one plant genome to encode the necessary enzymes, and just as a plant lineage acquires the ability to make new specialized compounds during evolution, it also loses the ability to make others. Although the ability of plants to make novel, specialized metabolites continues to evolve, there are also many examples in which different plants have independently evolved the ability to make compounds already present in other plant lineages or to make different compounds that fulfill the same role-both are examples of convergent evolution. Here, we discuss many examples of convergent evolution in specialized metabolism. There are many genetic and biochemical mechanisms that can give rise to convergent evolution, and we conclude that, overall, convergent evolution in plant specialized metabolism is surprisingly common.
[Conservative and surgical treatment of convergence excess].
Ehrt, O
2016-07-01
Convergence excess is a common finding especially in pediatric strabismus. A detailed diagnostic approach has to start after full correction of any hyperopia measured in cycloplegia. It includes measurements of manifest and latent deviation at near and distance fixation, near deviation after relaxation of accommodation with addition of +3 dpt, assessment of binocular function with and without +3 dpt as well as the accommodation range. This diagnostic approach is important for the classification into three types of convergence excess, which require different therapeutic approaches: 1) hypo-accommodative convergence excess is treated with permanent bifocal glasses, 2) norm-accommodative patients should be treated with bifocals which can be weaned over years, especially in patients with good stereopsis and 3) non-accommodative convergence excess and patients with large distance deviations need a surgical approach. The most effective operations include those which reduce the muscle torque, e. g. bimedial Faden operations or Y‑splitting of the medial rectus muscles.
Improving Results on Convergence of AOR Method
Guangbin Wang
2012-01-01
Full Text Available We present some sufficient conditions on convergence of AOR method for solving Ax=b with A being a strictly doubly α diagonally dominant matrix. Moreover, we give two numerical examples to show the advantage of the new results.
World health inequality: convergence, divergence, and development.
Clark, Rob
2011-02-01
Recent studies characterize the last half of the twentieth century as an era of cross-national health convergence, with some attributing welfare gains in the developing world to economic growth. In this study, I examine the extent to which welfare outcomes have actually converged and the extent to which economic development is responsible for the observed trends. Drawing from estimates covering 195 nations during the 1955-2005 period, I find that life expectancy averages converged during this time, but that infant mortality rates continuously diverged. I develop a narrative that implicates economic development in these contrasting trends, suggesting that health outcomes follow a "welfare Kuznets curve." Among poor countries, economic development improves life expectancy more than it reduces infant mortality, whereas the situation is reversed among wealthier nations. In this way, development has contributed to both convergence in life expectancy and divergence in infant mortality. Drawing from 674 observations across 163 countries during the 1980-2005 period, I find that the positive effect of GDP PC on life expectancy attenuates at higher levels of development, while the negative effect of GDP PC on infant mortality grows stronger.
Intermediates and Generic Convergence to Equilibria
Freitas, Michael Marcondes de; Wiuf, Carsten; Feliu, Elisenda
2016-01-01
Known graphical conditions for the generic or global convergence to equilibria of the dynamical system arising from a reaction network are shown to be invariant under the so-called successive removal of intermediates, a systematic procedure to simplify the network, making the graphical conditions...
Professionalization in Universities and European Convergence
Vivas, Amparo Jimenez; Hevia, David Menendez Alvarez
2009-01-01
The constant assessment of the quality of higher education within the framework of European convergence is a challenge for all those universities that wish their degrees and diplomas to reflect a unified Europe. As is the case in any assessment, change and review process, the quest to improve quality implies measuring achievement of the objectives…
Converging technologies: shaping the future of medicine
Iraj nabipour
2015-01-01
Full Text Available The miniaturization and virtualization processes drive converging technologies from interactions between the NBIC (Nano, Bio, Info, and Cogno technologies. The converging technologies stimulate innovation, promote research and development in different fields and produce revolutionary progresses in medicine. These technologies enable us to create contacts between brains and machines, the growth in molecular nanotechnology, the construction of respirocytes, chromallocytes, clottocytes, nanorobotic phagocytes, and nanobots. Nanobots would enter the nucleus of a cell and extract all of the genetic material and replace it with a synthetically produced copy of the original that has been manufactured in a laboratory to contain only non-defective base-pairs. It is predicted that “the regenerative medicine”, as a megatrend, will have an enormous effect on medical technologies and clinical sciences. Regenerative medicine is an application field of converging technologies in translational medicine. It attempts to translate the results of tissue engineering to construct 3D tissues and organs. Regenerative medicine is also an exciting field for induced pluripotent stem cell (iPSC and promises to bring about a paradigm shift to health care. Accumulating evidence indicates that converging technologies will offer great potentials for regenerative medicine to create innovative treatments for diseases that the traditional therapies have not been effective yet.
Sweet! Generation "D" Takes on Media Convergence.
Tarpenning, David; Schaub, Laura
2002-01-01
Notes that professional journalists continually emphasize the need for developing skills for all delivery systems. Proposes that students interested in journalism should learn about technology and develop projects without the guidance of a teacher or advisor. Describes students' experience with media convergence in a summer journalism workshop.…
RNA polymerase II collision interrupts convergent transcription
Hobson, David J; Wei, Wu; Steinmetz, Lars M
2012-01-01
Antisense noncoding transcripts, genes-within-genes, and convergent gene pairs are prevalent among eukaryotes. The existence of such transcription units raises the question of what happens when RNA polymerase II (RNAPII) molecules collide head-to-head. Here we use a combination of biochemical...
Biogeochemical drivers of microbial community convergence across actively retreating glaciers
Castle, Sarah C.; Nemergut, Diana R.; Grandy, A. Stuart; Leff, Jonathan W.; Graham, Emily B.; Hood, Eran; Schmidt, Steven K.; Wickings, Kyle; Cleveland, Cory C.
2016-10-01
The ecological processes that influence biogeographical patterns of microorganisms are actively debated. To investigate how such patterns emerge during ecosystem succession, we examined the biogeochemical drivers of bacterial community assembly in soils over two environmentally distinct, recently deglaciated chronosequences separated by a distance of more than 1,300 kilometers. Our results show that despite different geographic, climatic, and soil chemical and physical characteristics at the two sites, soil bacterial community structure and decomposer function converged during plant succession. In a comparative analysis, we found that microbial communities in early succession soils were compositionally distinct from a group of diverse, mature forest soils, but that the differences between successional soils and mature soils decreased from early to late stages of succession. Differences in bacterial community composition across glacial sites were largely explained by pH. However, successional patterns and community convergence across sites were more consistently related to soil organic carbon and organic matter chemistry, which appeared to be tightly coupled with bacterial community structure across both young and mature soils.
Multidimensional Convergence in Future 5G Networks
Ruffini, Marco
2017-02-01
Future 5G services are characterised by unprecedented need for high rate, ubiquitous availability, ultra-low latency and high reliability. The fragmented network view that is widespread in current networks will not stand the challenge posed by next generations of users. A new vision is required, and this paper provides an insight on how network convergence and application-centric approaches will play a leading role towards enabling the 5G vision. The paper, after expressing the view on the need for an end-to-end approach to network design, brings the reader into a journey on the expected 5G network requirements and outlines some of the work currently carried out by main standardisation bodies. It then proposes the use of the concept of network convergence for providing the overall architectural framework to bring together all the different technologies within a unifying and coherent network ecosystem. The novel interpretation of multi-dimensional convergence we introduce leads us to the exploration of aspects of node consolidation and converged network architectures, delving into details of optical-wireless integration and future convergence of optical data centre and access-metro networks. We then discuss how ownership models enabling network sharing will be instrumental in realising the 5G vision. The paper concludes with final remarks on the role SDN will play in 5G and on the need for new business models that reflect the application-centric view of the network. Finally, we provide some insight on growing research areas in 5G networking.
Edward Khawam; Bachir Abiad; Alaa Boughannam; Joanna Saade; Ramzi Alameddine
2015-01-01
Great discrepancies are often encountered between the distance fixation and the near-fixation esodeviations and exodeviations. They are all attributed to either anomalies of the AC/A ratio or anomalies of the fusional convergence or divergence amplitudes. We report a case with pseudoconvergence insufficiency and another one with pseudoaccommodative convergence excess. In both cases, conv./div. excess and insufficiency were erroneously attributed to anomalies of the AC/A ratio or to anomalies ...
DOES THE MAASTRICHT CONVERGENCE CRITERIA WORK?
Karsai ZoltÃ¡n-KrisztiÃ¡n
2012-12-01
Full Text Available During its 13 year history, the euro area experienced the most severe economic downturn in the late 2000s as a result of the 2007 financial-economic crisis stemming from the US banking sector. The crisis in the monetary union, besides posting a significant economic and social cost, revealed several weaknesses not just of the currency block as a whole, but also of its constituting members, which were masked by the prosperous economic environment characteristic for the 2000s. These conditions have put to the test the solidarity among the euro zone members, or in other words the existence of the currency block. One important problem of the currency block is the lack of harmony between the fiscal and economic policies of the member states, creating several and occasionally very divergent parts of the currency block. The aim of this research is to enhance the Maastricht convergence criteriaâ€™s and the Stability and Growth Pactâ€™s role as a monitoring mechanism, allowing them to become more informative tools for the policy makers. For this, based on the relevant literature, we propose new potential explanatory variables which could enhance the role of the Maastricht convergence criteria and the Stability and Growth Pact. Some of the studied variables, like indebtedness of the private sector, capital flow compared to the size of the economy, government revenue compared to total public debt and current account balance help in enforcing the nominal convergence, while others (real labour productivity contribute to the real convergence. The explanatory power of the proposed variables are investigated in the case of France, Germany, Greece, Ireland, Italy, Portugal and Spain for the period comprised between 2000Q1-2011Q4. Results of the research show that with the exception of government revenue compared to total public debt, all proposed variables have significant explanatory power regarding the evolution of the state of the economy in all
Convergence, divergence and realignment in British macroeconomics
D. COBHAM
2013-12-01
Full Text Available In this paper the author argues that the still frequent and simplistic distinction between Keynesians and monetarists that makes up a large part of the British popular economic debate has become seriously misleading. Changes that have taken place in British macroeconomics since the early 1970s are thus indicated and some of the theoretical and empirical factors responsible for these changes are suggested. The author presents a brief characterisation of British Keynesianism and monetarism as of late 1960s/early 1970s, arguing that there have been important elements of convergence. He proceeds to discuss some of the theoretical developments and some of the experiences of UK macroeconomic policy which have contributed to this convergence. Finally, he considers whether the labels “Keynesian” and “monetarist” continue to be relevant.
Neural networks convergence using physicochemical data.
Karelson, Mati; Dobchev, Dimitar A; Kulshyn, Oleksandr V; Katritzky, Alan R
2006-01-01
An investigation of the neural network convergence and prediction based on three optimization algorithms, namely, Levenberg-Marquardt, conjugate gradient, and delta rule, is described. Several simulated neural networks built using the above three algorithms indicated that the Levenberg-Marquardt optimizer implemented as a back-propagation neural network converged faster than the other two algorithms and provides in most of the cases better prediction. These conclusions are based on eight physicochemical data sets, each with a significant number of compounds comparable to that usually used in the QSAR/QSPR modeling. The superiority of the Levenberg-Marquardt algorithm is revealed in terms of functional dependence of the change of the neural network weights with respect to the gradient of the error propagation as well as distribution of the weight values. The prediction of the models is assessed by the error of the validation sets not used in the training process.
Invited paper: A Review of Thresheld Convergence
Stephen Chen
2015-07-01
Full Text Available A multi-modal search space can be defined as having multiple attraction basins – each basin has a single local optimum which is reached from all points in that basin when greedy local search is used. Optimization in multi-modal search spaces can then be viewed as a two-phase process. The first phase is exploration in which the most promising attraction basin is identified. The second phase is exploitation in which the best solution (i.e. the local optimum within the previously identified attraction basin is attained. The goal of thresheld convergence is to improve the performance of search techniques during the first phase of exploration. The effectiveness of thresheld convergence has been demonstrated through applications to existing metaheuristics such as particle swarm optimization and differential evolution, and through the development of novel metaheuristics such as minimum population search and leaders and followers.
Flow over convergent and divergent wall riblets
Koeltzsch, K.; Dinkelacker, A.; Grundmann, R. [Institut fuer Luft- und Raumfahrttechnik, Technische Universitaet Dresden, 36460 Merkers (Germany)
2002-08-01
Fast swimming sharks have small riblets on their skin, which are assumed to improve the swimming performance of the fish. Fluid dynamic experiments in water as well as in air confirm this assumption. With riblet surfaces as compared to smooth surfaces, drag reductions up to about 10% were measured. The overall riblet pattern on sharks shows parallel riblets directed from head to tail, but besides this overall pattern fast swimming sharks have also small areas with converging riblets and others with diverging riblets. In the present study the velocity field over convergent and divergent riblet patterns is investigated by hot-wire measurements in turbulent pipe flow. Significant changes in the near wall velocity field were found. (orig.)
Stability of spherical converging shock wave
Murakami, M., E-mail: murakami-m@ile.osaka-u.ac.jp [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Sanz, J. [ETSI Aeronauticos, Universidad Politecnica de Madrid, Madrid 28040 (Spain); Iwamoto, Y. [Graduate School of Science and Engineering, Ehime University, Ehime 790-8577 (Japan)
2015-07-15
Based on Guderley's self-similar solution, stability of spherical converging shock wave is studied. A rigorous linear perturbation theory is developed, in which the growth rate of perturbation is given as a function of the spherical harmonic number ℓ and the specific heats ratio γ. Numerical calculation reveals the existence of a γ-dependent cut-off mode number ℓ{sub c}, such that all the eigenmode perturbations for ℓ > ℓ{sub c} are smeared out as the shock wave converges at the center. The analysis is applied to partially spherical geometries to give significant implication for different ignition schemes of inertial confinement fusion. Two-dimensional hydrodynamic simulations are performed to verify the theory.
Rousseau and Marx: Convergence or divergence?
Lošonc Alpar
2012-01-01
Full Text Available Rousseau and Marx represent two paradigmatic variants of a radical opposition to the world. Without a doubt, there are significant moments of convergence between these thinkers, for instance in terms of division of labour, or in respect to the self-commandment. However, it is our contention that despite certain currents in literature, the tendencies of divergence are stronger than convergence, therefore, we argue that these thinkers signify two different variants of radical thought. We base these differences in a reading of Rousseau that focuses on collective authenticity, justice, self-presentation of people and protest against envy. Marx cannot be read from the perspective of the intensified crisis of non-authenticity, in fact, his critique of political economy generates a reflexive field (overcoming of the wage labour, etc., which is deeply divergent compared to Rousseau.
The genetic causes of convergent evolution.
Stern, David L
2013-11-01
The evolution of phenotypic similarities between species, known as convergence, illustrates that populations can respond predictably to ecological challenges. Convergence often results from similar genetic changes, which can emerge in two ways: the evolution of similar or identical mutations in independent lineages, which is termed parallel evolution; and the evolution in independent lineages of alleles that are shared among populations, which I call collateral genetic evolution. Evidence for parallel and collateral evolution has been found in many taxa, and an emerging hypothesis is that they result from the fact that mutations in some genetic targets minimize pleiotropic effects while simultaneously maximizing adaptation. If this proves correct, then the molecular changes underlying adaptation might be more predictable than has been appreciated previously.
Generalized functions, convergence structures, and their applications
Pap, Endre; Pilipović, Stevan; Vladimirov, Vasilij; International Conference "Generalized functions, convergence structures and their applications" (GFCA-87)
1988-01-01
This Proceedings consists of a collection of papers presented at the International Conference "Generalized functions, convergence structures and their applications" held from June 23-27, 1987 in Dubrovnik, Yugoslavia (GFCA-87): 71 participants from 21 countr~es from allover the world took part in the Conference. Proceedings reflects the work of the Conference. Plenary lectures of J. Burzyk, J. F. Colombeau, W. Gahler, H. Keiter, H. Komatsu, B. Stankovic, H. G. Tillman, V. S. Vladimirov provide an up-to-date account of the cur rent state of the subject. All these lectures, except H. G. Tillman's, are published in this volume. The published communications give the contemporary problems and achievements in the theory of generalized functions, in the theory of convergence structures and in their applications, specially in the theory of partial differential equations and in the mathematical physics. New approaches to the theory of generalized functions are presented, moti vated by concrete problems of applicat...
Service Creation and Deployment in Converged Networks
Soler, José
This monograph (Early Experiences related to Service Creation & Deployment in Converged Networks) presents different experiences related to architectures and mechanisms for deployment of telephony services, understood as especial features complementing the basic voice service. The context...... for these experiences is the transition of telecommunication (telephony) networks from circuit switched based systems towards packet based ones. The text of this monograph proceeds, unaltered for the most, from the author’s PhD thesis “Framework for Deployment of Advanced Telecommunication Services in Current...... and Future Converged Networks”, carried out at the Technical University of Denmark in the period [April 2002-April 2005]. Even though the technologies presented in the text have evolved from that period until now, the presented scenarios and setups are still valid as interesting initial steps in the realm....
Convergent designs for electrogenesis and electroreception.
Hopkins, C D
1995-12-01
New- and old-world tropical electric fish lack a common electrical ancestor, suggesting that the mechanisms of signal generation and recognition evolved independently in the two groups. Recent research on convergent designs for electrogenesis and electroreception has focused on the structure of electric organs, the neural circuitry controlling the pacemaker driving the electric organ, and the neural circuitry underlying time coding of electric waveforms.
Design calculations for NIF convergent ablator experiments
Olson R.E.
2013-11-01
Full Text Available The NIF convergent ablation tuning effort is underway. In the early experiments, we have discovered that the design code simulations over-predict the capsule implosion velocity and shock flash ρr, but under-predict the hohlraum x-ray flux measurements. The apparent inconsistency between the x-ray flux and radiography data implies that there are important unexplained aspects of the hohlraum and/or capsule behavior.
CONVERGENCE OF NONLINEAR CONJUGATE GRADIENT METHODS
Yu-hong Dai
2001-01-01
This paper proves that a simplified Armijo-type line search can ensure the global con vergences of the Fletcher-Reeves method and the Polak-Ribiére-Polyak method for un constrained optimization. Although it seems not possible to verify that the PRP method using the generalized Armijo line search converges globally for generally problems, it can be shown that in this case the PRP method always solves uniformly convex problems.
Arieti and Bowlby: convergence and direct influence.
Bacciagaluppi, Marco
2015-09-01
Arieti was a great specialist of schizophrenia and Bowlby was the initiator of attachment theory. Working independently on the two sides of the Atlantic, they converged on a range of topics, such as evolutionary theory, mourning, trauma, violence, and therapy as art and science. Later, Bowlby exerted a direct influence on Arieti, which Arieti acknowledged in his Love Can Be Found. Finally, the two authors cooperated in the second edition of the American Handbook of Psychiatry.
Wage sensitivity rankings and temporal convergence
Jones, Ronald W.; Neary, J. Peter
1988-01-01
This paper examines the two-sector general equilibrium model under a variety of labor-market distortions, including minimum wages and factor price differentials (both absolute and proportional). We introduce a new concept - the "wage sensitivity" ranking between sectors - and show that a necessary and sufficient condition for temporal convergence locally is that the physically labor-intensive sector be the wage-sensitive sector.
Economic Convergence : the East Asia evidence
Joian, Aref
2002-01-01
Summary "Economic Convergence, The East Asia evidence" generally includes a theoretical and an empirical part.. Part one present the neoclassical growth model, i.e., the so-called Solow-Swan model. We start from simple form, growth model with exogenous saving rate, no technical progress. As we know, Solow model is based on some assumptions, such as one-sector production, closed economy where output equals income, investment equals saving and constant rate of population growth and...
Convergence creates opportunities across health care system.
Fox, Brent I; Felkey, Bill G
2014-04-01
Industrial design students at Auburn do a creativity exercise where they are asked to combine a common household appliance with an animal. Have you seen a snake light? In health technology, we have a similar opportunity. In the connection between jewelry and vital sign monitoring technology or household security and health status monitoring, we are witnessing active convergence that will benefit patients, providers, and health systems.
COMPARATIVE FINANCIAL STATEMENTS. CONVERGENCE VERSUS DIVERGENCE
Nicolae ECOBICI
2010-09-01
Full Text Available In this paper I compared the Romanian financial statements with the US GAAP financial statements in terms of two criteria: first the reference period and secondly the shape, structure and content of financial statements. Nowadays the two accounting systems, the French and Anglo-Saxon, tend to harmonize. I will present the convergences and the divergences between the financial statements of Romania, subject to OMFP 3055/2009, in parallel with the Anglo-Saxon accounting system.
Curvature and bubble convergence of harmonic maps
Kokarev, Gerasim
2010-01-01
We explore geometric aspects of bubble convergence for harmonic maps. More precisely, we show that the formation of bubbles is characterised by the local excess of curvature on the target manifold. We give a universal estimate for curvature concentration masses at each bubble point and show that there is no curvature loss in the necks. Our principal hypothesis is that the target manifold is Kaehler.
Convergences in the diversification of bats
M. Brock Fenton
2010-01-01
Twenty-five characters or suites of characters from bats are considered in light of changes in bat classification. The characters include some associated with flower-visiting (two), echolocation (12), roosting (six), reproduction (two) and three are of unknown adaptive function. In both the 1998 and 2006 classifications of bats into suborders (Megachiroptera and Microchiroptera versus Yinpterochiroptera and Yangochiroptera, respectively), some convergences between suborders are the same (e.g....
Design calculations for NIF convergent ablator experiments
Olson R.E.; Hicks D.G.; Meezan N.B.; Callahan D.A.; Landen O.L.; Jones O.S.; Langer S.H.; Kline J.L.; Wilson D.C.; Rinderknecht H.; Zylstra A.; Petrasso R.D.
2013-01-01
The NIF convergent ablation tuning effort is underway. In the early experiments, we have discovered that the design code simulations over-predict the capsule implosion velocity and shock flash ρr, but under-predict the hohlraum x-ray flux measurements. The apparent inconsistency between the x-ray flux and radiography data implies that there are important unexplained aspects of the hohlraum and/or capsule behavior.
Bandlimited image extrapolation with faster convergence
Cahana, D.; Stark, H.
1981-08-01
Techniques for increasing the convergence rate of the extrapolation algorithm proposed by Gerchberg (1974) and Papoulis (1975) for image restoration applications are presented. The techniques involve the modification of the Gerchberg-Papoulis algorithm to include additional a priori data such as the low-pass projection of the image either by the inclusion of the data at the start of the recursion to reduce the starting-point error, or by use of the low-pass image in each iteration to correct twice in the frequency domain. The performance of the GP algorithm and the two modifications presented in the restorations of a signal consisting of widely separated spectral components of equal magnitude and a signal with spectral components grouped in passbands is compared, and it is found that while both modifications reduced the starting point error, the convergence rate of the second technique was not substantially greater than that of the first despite the additional iterative frequency-plane correction. A significant improvement in the starting-point errors and convergence rates of both modified algorithms is obtained, however, when they are combined with adaptive thresholding in the presence of low noise levels and a signal with relatively well spaced impulse-type spectral components.
Automatic Convergence Adjustment for Stereoscopy using Eye Tracking
Fisker, Martin; Gram, Kristoffer; Kronborg Thomsen, Kasper
When using stereoscopic displays, decoupling between convergence and accommodation can cause eyestrain. This paper proposes an adjustment method to automatically fit convergence at user fixation depth to accommodation by using eye tracking. Two different adjustment methods are proposed: one...
Theoretical analysis on convergence behavior of rank filters
YE; Wanzhou
2004-01-01
This paper systematically studies the convergence behavior of rank filters. The problem of convergence behavior of rank filters has been solved completely for bounded sequences. Moreover, some properties of its limiting sequences and recurrent sequences are obtained.
Convergence of a Moran model to Eigen's quasispecies model.
Dalmau, Joseba
2017-03-02
We prove that a Moran model converges in probability to Eigen's quasispecies model in the infinite population limit. We show further that the invariant probability measure of the Moran model converges to the unique stationary solution of Eigen's quasispecies model.
Probabilistic norms and statistical convergence of random variables
Mohamad Rafi Segi Rahmat
2009-03-01
Full Text Available The paper extends certain stochastic convergence of sequences of Rk -valued random variables (namely, the convergence in probability, in Lp and almost surely to the context of E-valued random variables.
Stamou, Marianna; Streifel, Karin M; Goines, Paula E; Lein, Pamela J
2013-01-01
Evidence implicates environmental factors in the pathogenesis of Autism Spectrum Disorders (ASD). However, the identity of specific environmental chemicals that influence ASD risk, severity or treatment outcome remains elusive. The impact of any given environmental exposure likely varies across a population according to individual genetic substrates, and this increases the difficulty of identifying clear associations between exposure and ASD diagnoses. Heritable genetic vulnerabilities may amplify adverse effects triggered by environmental exposures if genetic and environmental factors converge to dysregulate the same signaling systems at critical times of development. Thus, one strategy for identifying environmental risk factors for ASD is to screen for environmental factors that modulate the same signaling pathways as ASD susceptibility genes. Recent advances in defining the molecular and cellular pathology of ASD point to altered patterns of neuronal connectivity in the developing brain as the neurobiological basis of these disorders. Studies of syndromic ASD and rare highly penetrant mutations or CNVs in ASD suggest that ASD risk genes converge on several major signaling pathways linked to altered neuronal connectivity in the developing brain. This review briefly summarizes the evidence implicating dysfunctional signaling via Ca(2+)-dependent mechanisms, extracellular signal-regulated kinases (ERK)/phosphatidylinositol-3-kinases (PI3K) and neuroligin-neurexin-SHANK as convergent molecular mechanisms in ASD, and then discusses examples of environmental chemicals for which there is emerging evidence of their potential to interfere with normal neuronal connectivity via perturbation of these signaling pathways.
Convergence Analysis for the Multiplicative Schwarz Preconditioned Inexact Newton Algorithm
Liu, Lulu
2016-10-26
The multiplicative Schwarz preconditioned inexact Newton (MSPIN) algorithm, based on decomposition by field type rather than by subdomain, was recently introduced to improve the convergence of systems with unbalanced nonlinearities. This paper provides a convergence analysis of the MSPIN algorithm. Under reasonable assumptions, it is shown that MSPIN is locally convergent, and desired superlinear or even quadratic convergence can be obtained when the forcing terms are picked suitably.
Convergence in the EU related to the Maastricht criteria
Magdaléna DRASTICHOVÁ
2013-01-01
Regarding the entry into the euro area, the convergence of the EU economies can be monitored in several dimensions. One of them is the convergence represented by the Maastricht criteria, which are the only official conditions of joining the euro area for the EU countries. The aim of this paper is to detect the development of convergence related to these criteria in the EU and to draw mutual relations between the convergence criteria and the impact of compliance with these criteria...
The Mackey convergence condition for spaces with webs
Thomas E. Gilsdorf
1988-01-01
Full Text Available If each sequence converging to 0 in a locally convex space is also Mackey convergent to 0, that space is said to satisfy the Mackey convergence condition. The problem of characterizing those locally convex spaces with this property is still open. In this paper, spaces with compatible webs are used to construct both a necessary and a sufficient condition for a locally convex space to satisfy the Mackey convergence condition.
Modular Filter Convergence Theorems for Urysohn Integral Operators and Applications
Antonio BOCCUTO; Xenofon DIMITRIOU
2013-01-01
We prove some versions of modular convergence theorems for nonlinear Urysohn-type integral operators with respect to filter convergence.We consider pointwise filter convergence of functions giving also some applications to linear and nonlinear Mellin operators.We show that our results are strict extensions of the classical ones.
Convergent variational calculation of positronium-hydrogen-atom scattering lengths
Adhikari, S K; Adhikari, Sadhan K.; Mandal, Puspajit
2001-01-01
We present a convergent variational basis-set calculational scheme for elastic scattering of positronium atom by hydrogen atom in S wave. Highly correlated trial functions with appropriate symmetry are needed for achieving convergence. We report convergent results for scattering lengths in atomic units for both singlet ($=3.49\\pm 0.20$) and triplet ($=2.46\\pm 0.10$) states.
Evaluation of Convergent Spray Technology(TM) Spray Process for Roof Coating Application
Scarpa, J.; Creighton, B.; Hall, T.; Hamlin, K.; Howard, T.
1998-01-01
The overall goal of this project was to demonstrate the feasibility of(CST) Convergent Spray Technology (Trademark) for the roofing industry. This was accomplished by producing an environmentally compliant coating utilization recycled materials, a CST(Trademark) spray process portable application cart, and hand-held applicator with a CST(Trademark) spray process nozzle. The project culminated with application of this coating to a nine hundred sixty square foot metal for NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama.
A Globally Convergent Matrix-Free Method for Constrained Equations and Its Linear Convergence Rate
Min Sun
2014-01-01
Full Text Available A matrix-free method for constrained equations is proposed, which is a combination of the well-known PRP (Polak-Ribière-Polyak conjugate gradient method and the famous hyperplane projection method. The new method is not only derivative-free, but also completely matrix-free, and consequently, it can be applied to solve large-scale constrained equations. We obtain global convergence of the new method without any differentiability requirement on the constrained equations. Compared with the existing gradient methods for solving such problem, the new method possesses linear convergence rate under standard conditions, and a relax factor γ is attached in the update step to accelerate convergence. Preliminary numerical results show that it is promising in practice.
Bainbridge, William; Tonn, Bruce; Whitesides, George
2013-01-01
Convergence of knowledge and technology for the benefit of society (CKTS) is the core opportunity for progress in the 21st century, based on five principles: (1) the interdependence of all components of nature and society, (2) enhancement of creativity and innovation through evolutionary processes of convergence that combine existing principles, and divergence that generates new ones, (3) decision analysis for research and development based on system-logic deduction, (4) higher-level cross-domain languages to generate new solutions and support transfer of new knowledge, and (5) vision-inspired basic research embodied in grand challenges. Solutions are outlined for key societal challenges, including creating new industries and jobs, improving lifelong wellness and human potential, achieving personalized and integrated healthcare and education, and securing a sustainable quality of life for all. This report provides a ten-year “NBIC2” vision within a longer-term framework for converging technology and human...
Is the convergence of the manufacturing sector unconditional?
Juliano Assunção
2015-09-01
Full Text Available In Unconditional Convergence, Rodrik (2011b documented that manufacturing industries exhibit unconditional convergence in labor productivity. We provide a novel semi-parametric specification for convergence equations and show that the speed of convergence varies systematically with country-specific characteristics. We consider the flexible smooth transition model with multiple transition variables, which allows each group to have distinct dynamics controlled by a linear combination of known variables. We found evidence that the laws of motion for industry productivity growth are different across countries, varying with political institutions. The speed of convergence also has a non-monotonic relationship with trade openness and education.
Rapid convergent evolution in wild crickets.
Pascoal, Sonia; Cezard, Timothee; Eik-Nes, Aasta; Gharbi, Karim; Majewska, Jagoda; Payne, Elizabeth; Ritchie, Michael G; Zuk, Marlene; Bailey, Nathan W
2014-06-16
The earliest stages of convergent evolution are difficult to observe in the wild, limiting our understanding of the incipient genomic architecture underlying convergent phenotypes. To address this, we capitalized on a novel trait, flatwing, that arose and proliferated at the start of the 21st century in a population of field crickets (Teleogryllus oceanicus) on the Hawaiian island of Kauai. Flatwing erases sound-producing structures on male forewings. Mutant males cannot sing to attract females, but they are protected from fatal attack by an acoustically orienting parasitoid fly (Ormia ochracea). Two years later, the silent morph appeared on the neighboring island of Oahu. We tested two hypotheses for the evolutionary origin of flatwings in Hawaii: (1) that the silent morph originated on Kauai and subsequently introgressed into Oahu and (2) that flatwing originated independently on each island. Morphometric analysis of male wings revealed that Kauai flatwings almost completely lack typical derived structures, whereas Oahu flatwings retain noticeably more wild-type wing venation. Using standard genetic crosses, we confirmed that the mutation segregates as a single-locus, sex-linked Mendelian trait on both islands. However, genome-wide scans using RAD-seq recovered almost completely distinct markers linked with flatwing on each island. The patterns of allelic association with flatwing on either island reveal different genomic architectures consistent with the timing of two mutational events on the X chromosome. Divergent wing morphologies linked to different loci thus cause identical behavioral outcomes--silence--illustrating the power of selection to rapidly shape convergent adaptations from distinct genomic starting points. Copyright © 2014 Elsevier Ltd. All rights reserved.
Electrospinning versus fibre production methods: from specifics to technological convergence.
Luo, C J; Stoyanov, Simeon D; Stride, E; Pelan, E; Edirisinghe, M
2012-07-07
Academic and industrial research on nanofibres is an area of increasing global interest, as seen in the continuously multiplying number of research papers and patents and the broadening range of chemical, medical, electrical and environmental applications. This in turn expands the size of the market opportunity and is reflected in the significant rise of entrepreneurial activities and investments in the field. Electrospinning is probably the most researched top-down method to form nanofibres from a remarkable range of organic and inorganic materials. It is well known and discussed in many comprehensive studies, so why this review? As we read about yet another "novel" method producing multifunctional nanomaterials in grams or milligrams in the laboratory, there is hardly any research addressing how these methods can be safely, consistently and cost-effectively up-scaled. Despite two decades of governmental and private investment, the productivity of nanofibre forming methods is still struggling to meet the increasing demand. This hinders the further integration of nanofibres into practical large-scale applications and limits current uses to niche-markets. Looking into history, this large gap between supply and demand of synthetic fibres was seen and addressed in conventional textile production a century ago. The remarkable achievement was accomplished via extensive collaborative research between academia and industry, applying ingenious solutions and technological convergence from polymer chemistry, physical chemistry, materials science and engineering disciplines. Looking into the present, current advances in electrospinning and nanofibre production are showing similar interdisciplinary technological convergence, and knowledge of industrial textile processing is being combined with new developments in nanofibre forming methods. Moreover, many important parameters in electrospinning and nanofibre spinning methods overlap parameters extensively studied in industrial
Rates of Convergence of Recursively Defined Sequences
Lambov, Branimir Zdravkov
2005-01-01
This paper gives a generalization of a result by Matiyasevich which gives explicit rates of convergence for monotone recursively defined sequences. The generalization is motivated by recent developments in fixed point theory and the search for applications of proof mining to the field. It relaxes...... the requirement for monotonicity to the form xn+1 ≤ (1+an)xn+bn where the parameter sequences have to be bounded in sum, and also provides means to treat computational errors. The paper also gives an example result, an application of proof mining to fixed point theory, that can be achieved by the means discussed...
Convergence Analysis of a Domain Decomposition Paradigm
Bank, R E; Vassilevski, P S
2006-06-12
We describe a domain decomposition algorithm for use in several variants of the parallel adaptive meshing paradigm of Bank and Holst. This algorithm has low communication, makes extensive use of existing sequential solvers, and exploits in several important ways data generated as part of the adaptive meshing paradigm. We show that for an idealized version of the algorithm, the rate of convergence is independent of both the global problem size N and the number of subdomains p used in the domain decomposition partition. Numerical examples illustrate the effectiveness of the procedure.
ON SEMILOCAL CONVERGENCE OF INEXACT NEWTON METHODS
Xueping Guo
2007-01-01
Inexact Newton methods are constructed by combining Newton's method with another iterative method that is used to solve the Newton equations inexactly. In this paper, we establish two semilocal convergence theorems for the inexact Newton methods. When these two theorems are specified to Newton's method, we obtain a different Newton-Kantorovich theorem about Newton's method. When the iterative method for solving the Newton equations is specified to be the splitting method, we get two estimates about the iteration steps for the special inexact Newton methods.
Converging posterior distributions in space debris monitoring
Lasanen, Sari [Department of Mathematical Sciences, University of Oulu, 90014 University of Oulu (Finland)], E-mail: sari.lasanen@oulu.fi
2008-11-01
Ground-based radars monitor the falling space debris in order to prevent collisions with spacecrafts and satellites. Experiments with European Incoherent Scatter (EISCAT) Scientific Association radars using new data acquisition equipment suitable for space debris detection have raised a question what happens to a Bayesian solution when the sampling frequency of the reflected signal is increased. Assuming slightly idealized measurements, we show that the posterior densities converge in this case. This shows that the sampling method suits well for the statistical inverse problem.
Exponentially Convergent Algorithms for Abstract Differential Equations
Gavrilyuk, Ivan; Vasylyk, Vitalii
2011-01-01
This book presents new accurate and efficient exponentially convergent methods for abstract differential equations with unbounded operator coefficients in Banach space. These methods are highly relevant for the practical scientific computing since the equations under consideration can be seen as the meta-models of systems of ordinary differential equations (ODE) as well as the partial differential equations (PDEs) describing various applied problems. The framework of functional analysis allows one to obtain very general but at the same time transparent algorithms and mathematical results which
Strategies for fast convergence in semiotic dynamics
Baronchelli, A; Dall'Asta, L; Loreto, V; Asta, Luca Dall'; Baronchelli, Andrea; Barrat, Alain; Loreto, Vittorio
2005-01-01
Semiotic dynamics is a novel field that studies how semiotic conventions spread and stabilize in a population of agents. This is a central issue both for theoretical and technological reasons since large system made up of communicating agents, like web communities or artificial embodied agents teams, are getting widespread. In this paper we discuss a recently introduced simple multi-agent model which is able to account for the emergence of a shared vocabulary in a population of agents. In particular we introduce a new deterministic agents' playing strategy that strongly improves the performance of the game in terms of faster convergence and reduced cognitive effort for the agents.
Blind image deconvolution methods and convergence
Chaudhuri, Subhasis; Rameshan, Renu
2014-01-01
Blind deconvolution is a classical image processing problem which has been investigated by a large number of researchers over the last four decades. The purpose of this monograph is not to propose yet another method for blind image restoration. Rather the basic issue of deconvolvability has been explored from a theoretical view point. Some authors claim very good results while quite a few claim that blind restoration does not work. The authors clearly detail when such methods are expected to work and when they will not. In order to avoid the assumptions needed for convergence analysis in the
Convergent and Divergent Adaptations of Subterranean Rodents
Fang, Xiaodong
) have evolved convergent and divergent traits in many of their morphological, physiological, and/or behavioral characteristics, which facilitate their adaptions to a similar underground burrowing life style. For example, all these three rodents show degenerate visual acuity and advanced sensory systems...... in the dark; they display remarkable tolerance to a living environment with an excess of carbon dioxide and ammonia, but lack of oxygen; they exhibit extraordinarily long lives, and keep a fantastic resistance to cancer and other aging-associated diseases. In this study, we reported the genomic...
Characterization of convergence in fuzzy topological spaces
E. Lowen
1985-01-01
Full Text Available In a fuzzy topology on a set X, the limit of a prefilter (i.e. a filter in the lattice [0,1]X is calculated from the fuzzy closure. In this way convergence is derived from a fuzzy topology. In our paper we start with any rule lim which to any prefilter on X assigns, a function lim∈[0,1]X. We give necessary and sufficient conditions for the function →lim in order that it can be derived from a fuzzy topology.
Convergent algorithms for protein structural alignment
Martínez José
2007-08-01
Full Text Available Abstract Background Many algorithms exist for protein structural alignment, based on internal protein coordinates or on explicit superposition of the structures. These methods are usually successful for detecting structural similarities. However, current practical methods are seldom supported by convergence theories. In particular, although the goal of each algorithm is to maximize some scoring function, there is no practical method that theoretically guarantees score maximization. A practical algorithm with solid convergence properties would be useful for the refinement of protein folding maps, and for the development of new scores designed to be correlated with functional similarity. Results In this work, the maximization of scoring functions in protein alignment is interpreted as a Low Order Value Optimization (LOVO problem. The new interpretation provides a framework for the development of algorithms based on well established methods of continuous optimization. The resulting algorithms are convergent and increase the scoring functions at every iteration. The solutions obtained are critical points of the scoring functions. Two algorithms are introduced: One is based on the maximization of the scoring function with Dynamic Programming followed by the continuous maximization of the same score, with respect to the protein position, using a smooth Newtonian method. The second algorithm replaces the Dynamic Programming step by a fast procedure for computing the correspondence between Cα atoms. The algorithms are shown to be very effective for the maximization of the STRUCTAL score. Conclusion The interpretation of protein alignment as a LOVO problem provides a new theoretical framework for the development of convergent protein alignment algorithms. These algorithms are shown to be very reliable for the maximization of the STRUCTAL score, and other distance-dependent scores may be optimized with same strategy. The improved score optimization
Species convergence into life-forms in a hyperseasonal cerrado in central Brazil.
Silva, I A; Batalha, M A
2008-05-01
Whether the functional structure of ecological communities is deterministic or historically contingent is still quite controversial. However, recent experimental tests did not find effects of species composition variation on trait convergence and therefore the environmental constraints should play the major role on community convergence into functional groups. Seasonal cerrados are characterized by a sharp seasonality, in which the water shortage defines the community functioning. Hyperseasonal cerrados experience additionally waterlogging in the rainy season. Here, we asked whether waterlogging modifies species convergences into life-forms in a hyperseasonal cerrado. We studied a hyperseasonal cerrado, comparing it with a nearby seasonal cerrado, never waterlogged, in Emas National Park, central Brazil. In each area, we sampled all vascular plants by placing 40 plots of 1 m(2) plots in four surveys. We analyzed the species convergences into life-forms in both cerrados using the Raunkiaer's life-form spectrum and the index of divergence from species to life-form diversity (IDD). The overall life-form spectra and IDDs were not different, indicating that waterlogging did not affect the composition of functional groups in the hyperseasonal cerrado. However, there was a seasonal variation in IDD values only in the hyperseasonal cerrado. As long as we did not find a seasonal variation in life-form diversity, the seasonal variation of convergence into life-forms in the hyperseasonal cerrado was a consequence of the seasonal variation of species diversity. Because of high functional redundancy of cerrado plants, waterlogging promoted a floristic replacement without major changes in functional groups. Thus, waterlogging in the hyperseasonal cerrado promoted seasonal changes in species convergence into life-forms by reducing species diversity.
Characteristic analysis and prevention on premature convergence in genetic algorithms
徐宗本; 高勇
1997-01-01
The identification and characteristics of premature convergence in genetic algorithms (GAs) are investigated Through a detailed quantitative analysis on the search capability and the degree of population diversity, the cause of premature convergence in GAs is recognized, and attributed to the maturation effect of the GAs: The minimum schema deduced from current population, which is the largest search space of a GA, converges to a homogeneous population in probability 1 ( so the search capability of the GA decreases and premature convergence occurs). It is shown that, as quantitative features of the maturation effect, the degree of population diversity converges to zero with probability 1, and the tendency for premature convergence is inversely proportional to the population size and directly proportional to the variance of the fitness ratio of zero allele at any gene position of the current population. Based on the theoretical analysis, several strategies for preventing premature convergence are suggest
Geophysical constraints on geodynamical processes at convergent margins
Artemieva, Irina; Thybo, Hans; Shulgin, Alexey
2016-01-01
Convergent margins, being the boundaries between colliding lithospheric plates, form the most disastrous areas in the world due to intensive, strong seismicity and volcanism. We review global geophysical data in order to illustrate the effects of the plate tectonic processes at convergent margins...... on the crustal and upper mantle structure, seismicity, and geometry of subducting slab. We present global maps of free-air and Bouguer gravity anomalies, heat flow, seismicity, seismic Vs anomalies in the upper mantle, and plate convergence rate, as well as 20 profiles across different convergent margins....... A global analysis of these data for three types of convergent margins, formed by ocean-ocean, ocean-continent, and continent-continent collisions, allows us to recognize the following patterns. (1) Plate convergence rate depends on the type of convergent margins and it is significantly larger when...
CONVERGENCE OF REAL WAGES IN RURAL AREAS IN POLAND
Piotr Adamczyk
2016-06-01
Full Text Available The article concerns the spatial diversity of rural areas. The aim of the article is to evaluate whether the process of convergence of real wages in rural areas in Poland can be observed. The author focuses on two concepts of convergence: absolute (unconditional beta convergence and sigma convergence. The analysis regards rural districts at NUTS-4 level for 2002–2014. It was stated that rural areas in Poland became similar (converge in terms of real wages what can help reducing the diff erences in living standard of inhabitants. An estimated regression function confi rms the existence of absolute beta convergence process. The growth rate of real wages was relatively higher in the districts with lower initial level. Moreover, the research carried out by the author indicates a decreasing dispersion of wages among rural districts. It shows the existence of sigma convergence process.
OpenMC In Situ Source Convergence Detection
Aldrich, Garrett Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of California, Davis, CA (United States); Dutta, Soumya [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); The Ohio State Univ., Columbus, OH (United States); Woodring, Jonathan Lee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-05-07
We designed and implemented an in situ version of particle source convergence for the OpenMC particle transport simulator. OpenMC is a Monte Carlo based-particle simulator for neutron criticality calculations. For the transport simulation to be accurate, source particles must converge on a spatial distribution. Typically, convergence is obtained by iterating the simulation by a user-settable, fixed number of steps, and it is assumed that convergence is achieved. We instead implement a method to detect convergence, using the stochastic oscillator for identifying convergence of source particles based on their accumulated Shannon Entropy. Using our in situ convergence detection, we are able to detect and begin tallying results for the full simulation once the proper source distribution has been confirmed. Our method ensures that the simulation is not started too early, by a user setting too optimistic parameters, or too late, by setting too conservative a parameter.
Convergent evolution of the genomes of marine mammals
Foote, Andrew D.; Liu, Yue; Thomas, Gregg W.C.; Vinař, Tomáš; Alföldi, Jessica; Deng, Jixin; Dugan, Shannon; van Elk, Cornelis E.; Hunter, Margaret; Joshi, Vandita; Khan, Ziad; Kovar, Christie; Lee, Sandra L.; Lindblad-Toh, Kerstin; Mancia, Annalaura; Nielsen, Rasmus; Qin, Xiang; Qu, Jiaxin; Raney, Brian J.; Vijay, Nagarjun; Wolf, Jochen B. W.; Hahn, Matthew W.; Muzny, Donna M.; Worley, Kim C.; Gilbert, M. Thomas P.; Gibbs, Richard A.
2015-01-01
Marine mammals from different mammalian orders share several phenotypic traits adapted to the aquatic environment and therefore represent a classic example of convergent evolution. To investigate convergent evolution at the genomic level, we sequenced and performed de novo assembly of the genomes of three species of marine mammals (the killer whale, walrus and manatee) from three mammalian orders that share independently evolved phenotypic adaptations to a marine existence. Our comparative genomic analyses found that convergent amino acid substitutions were widespread throughout the genome and that a subset of these substitutions were in genes evolving under positive selection and putatively associated with a marine phenotype. However, we found higher levels of convergent amino acid substitutions in a control set of terrestrial sister taxa to the marine mammals. Our results suggest that, whereas convergent molecular evolution is relatively common, adaptive molecular convergence linked to phenotypic convergence is comparatively rare.
A network convergence zone in the hippocampus.
Bratislav Mišić
2014-12-01
Full Text Available The hippocampal formation is a key structure for memory function in the brain. The functional anatomy of the brain suggests that the hippocampus may be a convergence zone, as it receives polysensory input from distributed association areas throughout the neocortex. However, recent quantitative graph-theoretic analyses of the static large-scale connectome have failed to demonstrate the centrality of the hippocampus; in the context of the whole brain, the hippocampus is not among the most connected or reachable nodes. Here we show that when communication dynamics are taken into account, the hippocampus is a key hub in the connectome. Using a novel computational model, we demonstrate that large-scale brain network topology is organized to funnel and concentrate information flow in the hippocampus, supporting the long-standing hypothesis that this region acts as a critical convergence zone. Our results indicate that the functional capacity of the hippocampus is shaped by its embedding in the large-scale connectome.
The Origin of Weak Lensing Convergence Peaks
Liu, Jia
2016-01-01
Weak lensing convergence peaks are a promising tool to probe nonlinear structure evolution at late times, providing additional cosmological information beyond second-order statistics. Previous theoretical and observational studies have shown that the cosmological constraints on $\\Omega_m$ and $\\sigma_8$ are improved by a factor of up to ~ 2 when peak counts and second-order statistics are combined, compared to using the latter alone. We study the origin of lensing peaks using observational data from the 154 deg$^2$ Canada-France-Hawaii Telescope Lensing Survey. We found that while high peaks (with height $\\kappa$ >3.5 $\\sigma_\\kappa$, where $\\sigma_\\kappa$ is the r.m.s. of the convergence $\\kappa$) are typically due to one single massive halo of ~$10^{15}M_\\odot$, low peaks ($\\kappa$ ~ their virial radii), compared with ~0.25 virial radii for halos linked with high peaks, hinting that low peaks are more immune to baryonic processes whose impact is confined to the inner regions of the dark matter halos. Our fi...
CONVERGENCE IN THE EUROPEAN SOCIAL POLICY
Mariana Iovitu
2012-07-01
Full Text Available The European Union has developed a series of strategies that aim to limit the consequences of non-employment (due to the continuing crisis. These strategies aim by the objectives and mechanisms specific to the eco-social area, to improve the access to employment, social services, professional education and a more efficient European fund management. All this are subordinated to the coupling policy public-private in terms of partnerships both at a national level and European level. The problem is related to differences manifested between the social objectives at the national level and those imposed by the European context. The differences come from different degrees of economic development of the member states, economic development which is reflected on the living standards. The convergence between the social policies is based on the economic convergence, which represents the only way to ameliorate the discrepancies between the united nations of Europe. Social Europe dream or certainty? The answer can be found in the words of Jean Monnet: â€œwe are not bringing together states, we are uniting peopleâ€. The efforts to define the four types of actions regarding the free movement of labor force and the correlation of the social security schemes, ensuring equal opportunities, respecting labor rights and the fight against discrimination can be found in the results obtained on these priorities.
Instability and Tsunamigenic Potential at Convergent Margins
von Huene, R.; Ranero, C. R.; Watts, P.
2001-12-01
Along many convergent margins multibeam echosounding navigated with GPS has revealed large slope failures that were probably tsunamigenic. Bathymetric data combined with seismic reflection imaging indicate multiple causes. The 55-km wide Nicoya Slump resulted from the steepening slope above an underthrusting seamount on the subducting oceanic plate. This slump may have generated a 27-m high wave. Several 5-7 km wide mid-slope slides off central Nicaragua probably resulted from steepening of the continental slope by tectonic erosion. They may have generated waves 6-7 m high. A 30 km wide mid-slope slump off northern Peru may have generated a 5 m high wave. Its cause will not be understood without better seismic reflection imaging but considerable fluid venting was observed across its headwall. In the Gulf of Alaska a large slide appears to have resulted from rapid sedimentation. Tsunamigenic slope failure along convergent margins is only beginning to be resolved and the causes vary. Subducted ocean floor relief, tectonically steepened slopes, and sites of rapid sedimentation can help target potential failure and possible future tsunami hazards.
Polyclonal clustering algorithm and its convergence
MA Li; JIAO Li-cheng; BAI Lin; CHEN Chang-guo
2008-01-01
Being characteristic of non-teacher learning, self-organization, memory, and noise resistance, the artificial immune system is a research focus in the field of intelligent information processing. Based on the basic principles of organism immune and clonal selection, this article presents a polyclonal clustering algorithm characteristic of self-adaptation. According to the core idea of the algorithm, various immune operators in the artificial immune system are employed in the clustering process; moreover, clustering numbers are adjusted in accordance with the affinity function. Introduction of the recombination operator can effectively enhance the diversity of the individual antibody in a generation population, so that the searching scope for solutions is enlarged and the premature phenomenon of the algorithm is avoided. Besides, introduction of the inconsistent mutation operator enhances the adaptability and optimizes the performance of local solution seeking. Meanwhile, the convergence of the algorithm is accelerated. In addition, the article also proves the convergence of the algorithm by employing the Markov chain. Results of the data simulation experiment show that the algorithm is capable of obtaining reasonable and effective cluster.
Convergences in the diversification of bats
M. Brock FENTON
2010-08-01
Full Text Available Twenty-five characters or suites of characters from bats are considered in light of changes in bat classification. The characters include some associated with flower-visiting (two, echolocation (12, roosting (six, reproduction (two and three are of unknown adaptive function. In both the 1998 and 2006 classifications of bats into suborders (Megachiroptera and Microchiroptera versus Yinpterochiroptera and Yangochiroptera, respectively, some convergences between suborders are the same (e.g., foliage roosting, tent building, but others associated with echolocation differ substantially. In the 1998 phylogeny convergences associated with echolocation (high duty cycle echolocation, nasal emission of echolocation calls occurred among the Microchiroptera. In the 2006 phylogeny, they occur between Yinpterochiroptera and Yangochiroptera. While some traits apparently arose independently in two suborders (e.g., foliage-roosting, tent building, low intensity echolocation calls, noseleafs, nasal emission of echolocation calls, high duty cycle echolocation behaviour, others appear to have been ancestral (roosting in narrow spaces, laryngeal echolocation, stylohyal-tympanic contact, oral emission of echolocation calls, and small litter size. A narrow profile through the chest is typical of bats reflecting the thoracic skeleton. This feature suggests that the ancestors of bats spent the day in small crevices. Features associated with laryngeal echolocation appear to be ancestral, suggesting that echolocation evolved early in bats but was subsequently lost in one yinpterochiropteran lineage [Current Zoology 56 (4: 454–468, 2010].
Symbolic convergence and the hydrogen economy
Sovacool, Benjamin K. [Lee Kuan Yew School of Public Policy, 469C Bukit Timah Road, National University of Singapore, Singapore 259772 (Singapore); Brossmann, Brent [Tim Russert Department of Communication and Theatre Arts, O' Malley Center Room 59, John Carroll University, 20700 North Park Boulevard, Cleveland, OH 44118 (United States)
2010-04-15
This article documents that the hydrogen economy continues to attract significant attention among politicians, the media, and some academics. We believe that an explanation lies in the way that the hydrogen economy fulfills psychological and cultural needs related to a future world where energy is abundant, cheap, and pollution-free, a 'fantasy' that manifests itself with the idea that society can continue to operate without limits imposed by population growth and the destruction of the environment. The article begins by explaining its research methodology consisting of two literature reviews, research interviews of energy experts, and the application of symbolic convergence theory, a general communications theory about the construction of rhetorical fantasies. We then identify a host of socio-technical challenges to explain why the creation of a hydrogen economy would present immense (and possibly intractable) obstacles, an argument supplemented by our research interviews. Next, we employ symbolic convergence theory to identify five prevalent fantasy themes and rhetorical visions - independence, patriotism, progress, democratization, and inevitability - in academic and public discussions in favor of the hydrogen economy. We conclude by offering implications for scholarship relating to energy policy more broadly. (author)
Simulations of 2-shock Convergence Scan Shots
Bradley, Paul; Olson, R. E.; Kline, J. L.; MacLaren, S. A.; Ma, T.; Salmonson, J. D.; Kyrala, G. A.; Pino, J.; Dewald, E.; Khan, S.; Sayre, D.; Ralph, J.; Turnbull, D.
2016-10-01
The 2-shock campaign is a joint Los Alamos/Livermore project to investigate the role of shock timing, asymmetry, and shock convergence on the performance of ignition relevant capsules. This campaign uses a simple two step pulse that makes it easier to correlate the effect of changing the laser pulse on the performance of the capsule. The 680 micron outer radius capsule has a CH +1 at% Si ablator approximately 175 microns thick surrounding a DD or HT gas region with fill densities between 0.0085 and 0.00094 g/cc. The capsules are indirectly driven inside a gold hohlraum that is 9.2 mm long by 5.75 mm in diameter. Some capsules had about 3 microns of CD on the inner surface. The CD inner surface capsules utilized HT fuel so that the DT yield arises from mixing of CD shell material into the tritium of the gas region. Our simulated results compare well to the experimental yield, ion temperature, burn width, x-ray size, convergence ratio, and radius versus time data. Work performed by Los Alamos National Laboratory under contract DE-AC52-06NA25396 for the National Nuclear Security Administration of the U.S. Department of Energy.
Surgery for residual convergence excess esotropia.
Patel, Himanshu I; Dawson, Emma; Lee, John
2011-12-01
The outcome of bilateral medial rectus posterior fixation sutures +/- central tenotomy was assessed as a secondary procedure for residual convergence excess esotropia in 11 patients. Ten had previously undergone bilateral medial rectus recessions. One had recess/resect surgery on the deviating eye. The average preoperative near angle was 30 prism diopters with a range of 16 to 45 prism diopters. Eight patients underwent bilateral medial rectus posterior fixation sutures with central tenotomy. Two had bilateral medial rectus posterior fixation sutures only, and one had bilateral medial rectus posterior fixation suture, a lateral rectus resection, and an inferior oblique disinsertion. The postoperative near angle ranged from 4-30 prism diopters, with mean of 12 prism diopters. Five patients demonstrated some stereopsis preoperatively, all needing bifocals. Postoperatively, nine patients demonstrated an improvement in stereopsis, none needing bifocals. Two showed smaller near angles and better control without bifocals. Final stereopsis ranged from 30 seconds of arc to 800 seconds of arc. We feel that bilateral medial rectus posterior fixation sutures with or without central tenotomy is a viable secondary procedure for residual convergence excess esotropia.
Convergence of some leader election algorithms
Janson, Svante; Louchard, Guy
2008-01-01
We start with a set of n players. With some probability P(n,k), we kill n-k players; the other ones stay alive, and we repeat with them. What is the distribution of the number X_n of phases (or rounds) before getting only one player? We present a probabilistic analysis of this algorithm under some conditions on the probability distributions P(n,k), including stochastic monotonicity and the assumption that roughly a fixed proportion alpha of the players survive in each round. We prove a kind of convergence in distribution for X_n-log_a n, where the basis a=1/alpha; as in many other similar problems there are oscillations and no true limit distribution, but suitable subsequences converge, and there is an absolutely continuous random variable Z such that the distribution of X_n can be approximated by Z+log_a n rounded to the nearest larger integer. Applications of the general result include the leader election algorithm where players are eliminated by independent coin tosses and a variation of the leader electio...
Convergence of some leader election algorithms
Svante Janson
2008-08-01
Full Text Available We start with a set of n players. With some probability P(n,k, we kill n-k players; the other ones stay alive, and we repeat with them. What is the distribution of the number X n of phases (or rounds before getting only one player? We present a probabilistic analysis of this algorithm under some conditions on the probability distributions P(n,k, including stochastic monotonicity and the assumption that roughly a fixed proportion α of the players survive in each round. We prove a kind of convergence in distribution for X n - log 1/α n; as in many other similar problems there are oscillations and no true limit distribution, but suitable subsequences converge, and there is an absolutely continuous random variable Z such that d(X n, ⌈Z+ log 1/α n⌉→0, where d is either the total variation distance or the Wasserstein distance. Applications of the general result include the leader election algorithm where players are eliminated by independent coin tosses and a variation of the leader election algorithm proposed by W.R. Franklin 1982. We study the latter algorithm further, including numerical results.
Posterior fixation suture and convergence excess esotropia.
Steffen; Auffarth; Kolling
1998-09-01
The present study investigates the results of Cuppers' 'Fadenoperation' in patients with non-accommodative convergence excess esotropia. Particular attention is given to postoperative eye alignment at distance fixation. Group 1 (n=96) included patients with a 'normal' convergence excess. The manifest near angles (mean ET 16.73 degrees +/- 6.33 degrees, range 4 degrees -33 degrees ) were roughly twice the size of the distance angles (mean ET 6.50 degrees +/- 3.62 degrees, range 0 degrees -14 degrees ). These patients were treated with a bilateral fadenoperation of the medial recti without additional eye muscle surgery. Three months after surgery, the mean postoperative angles were XT 0.5 degrees +/- 3.3 degrees (range XT 11 degrees -ET 5 degrees ) for distance fixation, and ET 2.7 degrees +/- 3.6 degrees (range XT 5 degrees -ET 14 degrees ) for near fixation, respectively. Postoperative convergent angles at near fixation >ET 10 degrees were present in two patients (1.9%). Group 2 (n=21) included patients with a mean preoperative distance angle of ET 9.2 degrees +/- 3.7 degrees (range 6 degrees -16 degrees ) and a mean preoperative near angle of ET 23.4 degrees +/- 3.1 degrees (range 16 degrees -31 degrees ). These patients were operated on with a bilateral fadenoperation of the medial recti and a simultaneous recession of one or both medial rectus muscles. Mean postoperative angles were XT 0.5 degrees +/- 4.6 degrees (range XT 12 degrees -ET 7 degrees ) for distance fixation and ET 1.4 degrees +/- 4.5 degrees (range XT 8 degrees -ET 13 degrees ) for near fixation, respectively. In this group, 2 patients (10.6%) had a postoperative exotropia >XT 5 degrees at distance fixation, and two patients had residual esotropia>ET 10 degrees at near fixation. Group 3 (n=17) included patients with a pronounced non-accommodative convergence excess. Near angle values (mean of 17.8 degrees +/- 5.3 degrees, range ET 7 degrees -26 degrees ) were several times higher than the distance
Stayton, C. Tristan
2015-01-01
Convergent evolution is central to the study of life's evolutionary history. Researchers have documented the ubiquity of convergence and have used this ubiquity to make inferences about the nature of limits on evolution. However, these inferences are compromised by unrecognized inconsistencies in the definitions, measures, significance tests and inferred causes of convergent evolution. I review these inconsistencies and provide recommendations for standardizing studies of convergence. A fundamental dichotomy exists between definitions that describe convergence as a pattern and those that describe it as a pattern caused by a particular process. When this distinction is not acknowledged it becomes easy to assume that a pattern of convergence indicates that a particular process has been active, leading researchers away from alternative explanations. Convergence is not necessarily caused by limits to evolution, either adaptation or constraint; even substantial amounts of convergent evolution can be generated by a purely stochastic process. In the absence of null models, long lists of examples of convergent events do not necessarily indicate that convergence or any evolutionary process is ubiquitous throughout the history of life. Pattern-based definitions of convergence, coupled with quantitative measures and null models, must be applied before drawing inferences regarding large-scale limits to evolution. PMID:26640646
Real Economic Convergence in Western Europe from 1995 to 2013
Dzenita Siljak
2016-05-01
Full Text Available The aim of the paper is to analyze the economic convergence of real per capita GDP in the Western European countries with two types of measurement methodology. The first is sigma convergence, based on the coefficient of variation of real per capita GDP. The second is beta convergence, absolute/unconditional and conditional, including economic and socio-political variables, based on the neoclassical growth theory. The hypothesis of the paper is that there has been real economic convergence in Western Europe in at least one analyzed sub-period. The relationships between selected macroeconomic variables and the rate of economic growth are econometrically tested. Both sigma and beta convergence are estimated for the period 1995-2013 and four sub-periods: 1995-2003, 2004-2013, pre-crisis sub-period 2004-2008 and the crisis sub-period 2009-2013. The empirical findings support the hypothesis of economic convergence, i.e. that the poorer countries tend to grow faster than the rich ones in per capita terms, for some periods. However, the countries had a tendency to diverge, confiriming the negative effects of the crisis on per capita GDP growth. Sigma convergence is consistent with beta convergence. According to the results, the half-life of real convergence may take from 12 to 1078 years. Significant dissimilarities between the growth patterns among individual countries show the considerable heterogeneity of growth, i.e. the convergence clubs.
Converging shocks in elastic-plastic solids.
Ortega, A López; Lombardini, M; Hill, D J
2011-11-01
We present an approximate description of the behavior of an elastic-plastic material processed by a cylindrically or spherically symmetric converging shock, following Whitham's shock dynamics theory. Originally applied with success to various gas dynamics problems, this theory is presently derived for solid media, in both elastic and plastic regimes. The exact solutions of the shock dynamics equations obtained reproduce well the results obtained by high-resolution numerical simulations. The examined constitutive laws share a compressible neo-Hookean structure for the internal energy e=e(s)(I(1))+e(h)(ρ,ς), where e(s) accounts for shear through the first invariant of the Cauchy-Green tensor, and e(h) represents the hydrostatic contribution as a function of the density ρ and entropy ς. In the strong-shock limit, reached as the shock approaches the axis or origin r=0, we show that compression effects are dominant over shear deformations. For an isothermal constitutive law, i.e., e(h)=e(h)(ρ), with a power-law dependence e(h) is proportional to ρ(α), shock dynamics predicts that for a converging shock located at r=R(t) at time t, the Mach number increases as M is proportional to [log(1/R)](α), independently of the space index s, where s=2 in cylindrical geometry and 3 in spherical geometry. An alternative isothermal constitutive law with p(ρ) of the arctanh type, which enforces a finite density in the strong-shock limit, leads to M is proportional to R(-(s-1)) for strong shocks. A nonisothermal constitutive law, whose hydrostatic part e(h) is that of an ideal gas, is also tested, recovering the strong-shock limit M is proportional to R(-(s-1)/n(γ)) originally derived by Whitham for perfect gases, where γ is inherently related to the maximum compression ratio that the material can reach, (γ+1)/(γ-1). From these strong-shock limits, we also estimate analytically the density, radial velocity, pressure, and sound speed immediately behind the shock. While the
Converging shocks in elastic-plastic solids
López Ortega, A.; Lombardini, M.; Hill, D. J.
2011-11-01
We present an approximate description of the behavior of an elastic-plastic material processed by a cylindrically or spherically symmetric converging shock, following Whitham's shock dynamics theory. Originally applied with success to various gas dynamics problems, this theory is presently derived for solid media, in both elastic and plastic regimes. The exact solutions of the shock dynamics equations obtained reproduce well the results obtained by high-resolution numerical simulations. The examined constitutive laws share a compressible neo-Hookean structure for the internal energy e=es(I1)+eh(ρ,ς), where es accounts for shear through the first invariant of the Cauchy-Green tensor, and eh represents the hydrostatic contribution as a function of the density ρ and entropy ς. In the strong-shock limit, reached as the shock approaches the axis or origin r=0, we show that compression effects are dominant over shear deformations. For an isothermal constitutive law, i.e., eh=eh(ρ), with a power-law dependence eh∝ρα, shock dynamics predicts that for a converging shock located at r=R(t) at time t, the Mach number increases as M∝[log(1/R)]α, independently of the space index s, where s=2 in cylindrical geometry and 3 in spherical geometry. An alternative isothermal constitutive law with p(ρ) of the arctanh type, which enforces a finite density in the strong-shock limit, leads to M∝R-(s-1) for strong shocks. A nonisothermal constitutive law, whose hydrostatic part eh is that of an ideal gas, is also tested, recovering the strong-shock limit M∝R-(s-1)/n(γ) originally derived by Whitham for perfect gases, where γ is inherently related to the maximum compression ratio that the material can reach, (γ+1)/(γ-1). From these strong-shock limits, we also estimate analytically the density, radial velocity, pressure, and sound speed immediately behind the shock. While the hydrostatic part of the energy essentially commands the strong-shock behavior, the shear
A MATHEMATICAL THEORY FOR LES CONVERGENCE
H. Lim; B. Plohr; T. Kaman; Y. Yu; V. Mahadeo; Y. Xu; H. Zhang; J. Glimm; S. Dutta; D. H. Sharp
2012-01-01
Practical simulations of turbulent processes are generally cutoff,with a grid resolution that stops within the inertial range,meaning that multiple active regions and length scales occur below the grid level and are not resolved.This is the regime of large eddy simulations (LES),in which the larger but not the smaller of the turbulent length scales are resolved.Solutions of the fluid Navier-Stokes equations,when considered in the inertial regime,are conventionally regarded as solutions of the Euler equations.In other words,the viscous and diffusive transport terms in the Navier-Stokes equations can be neglected in the inertial regime and in LES simulations,while the Euler equation becomes fundamental.For such simulations,significant new solution details emerge as the grid is refined. It follows that conventional notions of grid convergence are at risk of failure,and that a new,and weaker notion of convergence may be appropriate.It is generally understood that the LES or inertial regime is inherently fluctuating and its description must be statistical in nature.Here we develop such a point of view systematically,based on Young measures,which are measures depending on or indexed by space time points.In the Young measure dv(ξ)x,t,the random variable ξ of the measure is a solution state variable,i.e.,a solution dependent variable,representing momentum,density,energy and species concentrations,while the space time coordinates,x,t,serve to index the measure.Theoretical evidence suggests that convergence via Young measures is sufficiently weak to encompass the LES/inertial regime; numerical and theoretical evidence suggests that this notion may be required for passive scalar concentration and thermal degrees of freedom.Our objective in this research is twofold:turbulent simulations without recourse to adjustable parameters (calibration) and extension to more complex physics,without use of additional models or parameters,in both cases with validation through comparison
Distributed Beamforming with Feedback: Convergence Analysis
Lin, C; Meyn, S
2008-01-01
The focus of this work is on the analysis of transmit beamforming schemes with a low-rate feedback link in wireless sensor/relay networks, where nodes in the network need to implement beamforming in a distributed manner. Specifically, the problem of distributed phase alignment is considered, where neither the transmitters nor the receiver has perfect channel state information, but there is a low-rate feedback link from the receiver to the transmitters. In this setting, a framework for systematically analyzing the performance of a general set of distributed beamforming schemes is proposed. To illustrate the advantage of this framework, a simple adaptive distributed beamforming scheme that was recently proposed by Mudambai et al. is studied. Two important properties for the received signal magnitude function are derived. Using these properties and the systematic framework, it is shown that the adaptive distributed beamforming scheme converges both in probability and in mean. Furthermore, it is established that ...
Convergence of recursive functions on computers
Erivelton Geraldo Nepomuceno
2014-10-01
Full Text Available A theorem is presented which has applications in the numerical computation of fixed points of recursive functions. If a sequence of functions {f(n} is convergent on a metric space I ⊆ ℝ, then it is possible to observe this behaviour on the set ⊂ ℚ of all numbers represented in a computer. However, as is not complete, the representation of f(n on is subject to an error. Then f(n and f(m are considered equal when its differences computed on are equal or lower than the sum of error of each f(n and f(m. An example is given to illustrate the use of the theorem.
Recorded Step Directional Mutation for Faster Convergence
Dunning, Ted
2008-01-01
Two meta-evolutionary optimization strategies described in this paper accelerate the convergence of evolutionary programming algorithms while still retaining much of their ability to deal with multi-modal problems. The strategies, called directional mutation and recorded step in this paper, can operate independently but together they greatly enhance the ability of evolutionary programming algorithms to deal with fitness landscapes characterized by long narrow valleys. The directional mutation aspect of this combined method uses correlated meta-mutation but does not introduce a full covariance matrix. These new methods are thus much more economical in terms of storage for problems with high dimensionality. Additionally, directional mutation is rotationally invariant which is a substantial advantage over self-adaptive methods which use a single variance per coordinate for problems where the natural orientation of the problem is not oriented along the axes.
Exploring Media Convergence: Evidence from Italy
Debora Bettiga
2013-12-01
Full Text Available The evolution of media and devices is enabling the ubiquitous and multi-device access to media and information, so that a media mutual contamination is in play. New forms of user interactions with media, in which different devices are used simultaneously in different contexts, have emerged. These new interactions are significantly impacting on users’ attitudes towards the media and their way of searching and generating content. Such a change, called “media convergence”, has a strong potential impact on marketing and communication processes, but as yet has not been deeply analysed in the literature. This paper presents the outcomes of several studies aimed at exploring media convergence on the demand-side to advance possible implications for marketers and managers.
Positive Cardiovascular Health: A Timely Convergence.
Labarthe, Darwin R; Kubzansky, Laura D; Boehm, Julia K; Lloyd-Jones, Donald M; Berry, Jarett D; Seligman, Martin E P
2016-08-23
Two concepts, positive health and cardiovascular health, have emerged recently from the respective fields of positive psychology and preventive cardiology. These parallel constructs are converging to foster positive cardiovascular health and a growing collaboration between psychologists and cardiovascular scientists to achieve significant improvements in both individual and population cardiovascular health. We explore these 2 concepts and note close similarities in the measures that define them, the health states that they aim to produce, and their intended long-term clinical and public health outcomes. We especially examine subjective health assets, such as optimism, that are a core focus of positive psychology, but have largely been neglected in preventive cardiology. We identify research to date on positive cardiovascular health, discuss its strengths and limitations thus far, and outline directions for further engagement of cardiovascular scientists with colleagues in positive psychology to advance this new field.
Weak Convergence Theorems for Nonself Mappings
Liu Yong-quan; Guo Wei-ping; Ji You-qing
2015-01-01
Let E be a real uniformly convex and smooth Banach space, and K be a nonempty closed convex subset of E with P as a sunny nonexpansive retrac-tion. Let T1, T2 : K → E be two weakly inward nonself asymptotically nonexpan-sive mappings with respect to P with a sequence {k(i)n } ⊂ [1,∞) (i = 1, 2), and F := F (T1)∩F (T2) = ∅. An iterative sequence for approximation common fixed points of the two nonself asymptotically nonexpansive mappings is discussed. If E has also a Fr´echet differentiable norm or its dual E∗ has Kadec-Klee property, then weak convergence theorems are obtained.
Reliability and Security - Convergence or Divergence
Emil BURTESCU
2010-01-01
Full Text Available Reliability, as every technical field, must adapt to the new demands imposed by reality. Started initially as a field designed to control and ensure the smooth functionality of an element or technical system, reliability has reached the stage where the discussion is about the reliability management, similar to the other top-level fields. Security has its own contribution to the reliability of a system; a reliable system is a system with reliable security. In order for a system to be reliable, that means clear and safe, all its components must be reliable. In the following pages we will talk about the two main facts - reliability and security - to determine both the convergence and the divergence points.
Biomedical engineering frontier research and converging technologies
Jun, Ho-Wook; Shin, Jennifer; Lee, SangHoon
2016-01-01
This book provides readers with an integrative overview of the latest research and developments in the broad field of biomedical engineering. Each of the chapters offers a timely review written by leading biomedical engineers and aims at showing how the convergence of scientific and engineering fields with medicine has created a new basis for practically solving problems concerning human health, wellbeing and disease. While some of the latest frontiers of biomedicine, such as neuroscience and regenerative medicine, are becoming increasingly dependent on new ideas and tools from other disciplines, the paradigm shift caused by technological innovations in the fields of information science, nanotechnology, and robotics is opening new opportunities in healthcare, besides dramatically changing the ways we actually practice science. At the same time, a new generation of engineers, fluent in many different scientific “languages,” is creating entirely new fields of research that approach the “old” questions f...
Convergent evolution in primates and an insectivore
Boffelli, Dario; Cheng, Jan-Fang; Rubin, Edward M.
2003-04-16
The cardiovascular risk factor apolipoprotein(a) (apo(a)) has a puzzling distribution among mammals, its presence being limited to a subset of primates and a member of the insectivore lineage, the hedgehog. To explore the evolutionary history of apo(a), we performed extensive genomic sequence comparisons of multiple species with and without an apo(a) gene product, such as human, baboon, hedgehog, lemurand mouse. This analysis indicated that apo(a) arose independently in a subset of primates, including baboon and human, and an insectivore, the hedgehog, and was not simply lost by species lacking it. The similar structural domains shared by the hedgehog and primate apo(a) indicate that they were formed by a unique molecular mechanism involving the convergent evolution of paralogous genes in these distantspecies.
Evolution and disease converge in the mitochondrion.
Mishmar, D; Zhidkov, I
2010-01-01
Mitochondrial DNA (mtDNA) mutations are long known to cause diseases but also underlie tremendous population divergence in humans. It was assumed that the two types of mutations differ in one major trait: functionality. However, evidence from disease association studies, cell culture and animal models support the functionality of common mtDNA genetic variants, leading to the hypothesis that disease-causing mutations and mtDNA genetic variants share considerable common features. Here we provide evidence showing that the two types of mutations obey the rules of evolution, including random genetic drift and natural selection. This similarity does not only converge at the principle level; rather, disease-causing mutations could recapitulate the ancestral DNA sequence state. Thus, the very same mutations could either mark ancient evolutionary changes or cause disease.
The CERN accelerators controls convergence project
Van den Eynden, Marc
1999-01-01
Summary form only given. The CERN PS and SL Accelerators controls groups have started in March 1998 a convergence effort aimed at building a common controls infrastructure for year 2001. The first activities concentrated on the definition of an object oriented Accelerator Device Model and Application Programming Interface (API) aimed at offering to high level application software developers a narrow and coherent view of the accelerator components. Efforts have also started to build the underlying middleware architecture that will support this model, including services based on the publish- subscribe paradigm. This presentation will highlight some aspects of this Accelerator Device model as seen form the application software level. A logical view of the associated middleware architecture that will transport Accelerator device data will also be discussed.
Divergence and Convergence in Education and Work
of institutions the central issue concerns the relation between learning environments. What is the coherence between school-based education and learning in the work-place, and how can they connect? Finally at the third level of the learners and their identities the focus is on the role of vocational educational...... training in the formation of biographies and identities.The book thus covers the central issues on the agenda in relation to future vocational education.......Are the educational systems in Europe becoming more similar or more different? This book deals with the issue ofdivergence and convergence in relation to systems, learning environments, and learners in vocational educational training (VET). 18 VET researchers from eight countries contribute...
TECHNOLOGICAL CONVERGENCE AND THE NEW JOURNALIST
David Renault
2013-12-01
Full Text Available Beginning in the 1990s, Brazilian means of communication have experienced a (still ongoing transformation process in the treadmill of technological advances, which have allowed for broad media convergence and for a single journalistic group to offer diverse products across various digital platforms. These transformations have impacted profoundly the routines of journalistic newsrooms and their professionals, from whom more and more agility is expected in order to meet the demands of the new era. This study seeks to demonstrate how the new reality affects the routines of newsrooms and journalists at the Brasilia offices of four of the most prominent newspaper groups in the country: O Estado de S. Paulo, Folha de S. Paulo, Valor Econômico and O Globo.
Convergence and fluctuations of Regularized Tyler estimators
Kammoun, Abla
2015-10-26
This article studies the behavior of regularized Tyler estimators (RTEs) of scatter matrices. The key advantages of these estimators are twofold. First, they guarantee by construction a good conditioning of the estimate and second, being a derivative of robust Tyler estimators, they inherit their robustness properties, notably their resilience to the presence of outliers. Nevertheless, one major problem that poses the use of RTEs in practice is represented by the question of setting the regularization parameter p. While a high value of p is likely to push all the eigenvalues away from zero, it comes at the cost of a larger bias with respect to the population covariance matrix. A deep understanding of the statistics of RTEs is essential to come up with appropriate choices for the regularization parameter. This is not an easy task and might be out of reach, unless one considers asymptotic regimes wherein the number of observations n and/or their size N increase together. First asymptotic results have recently been obtained under the assumption that N and n are large and commensurable. Interestingly, no results concerning the regime of n going to infinity with N fixed exist, even though the investigation of this assumption has usually predated the analysis of the most difficult N and n large case. This motivates our work. In particular, we prove in the present paper that the RTEs converge to a deterministic matrix when n → ∞ with N fixed, which is expressed as a function of the theoretical covariance matrix. We also derive the fluctuations of the RTEs around this deterministic matrix and establish that these fluctuations converge in distribution to a multivariate Gaussian distribution with zero mean and a covariance depending on the population covariance and the parameter.
Cooperative target convergence using multiple agents
Kwok, K.S.; Driessen, B.J.
1997-10-01
This work considers the problem of causing multiple (100`s) autonomous mobile robots to converge to a target and provides a follow-the-leader approach to the problem. Each robot has only a limited-range sensor for sending the target and also larger but also limited-range robot-to-robot communication capability. Because of the small amount of information available to the robots, a practical approach to improve convergence to the target is to have a robot follow the robot with the best quality of information. Specifically, each robot emits a signal that informs in-range robots what its status is. A robot has a status value of 0 if it is itself in range of the target. A robot has a status of 1 if it is not in range of the target but is in communication range of a robot that is in range of the target. A robot has a status of 2 if it is not in range of the target but is within range of another robot that has status 1, and so on. Of all the mobile robots that any given robot is in range of, it follows the one with the best status. The emergent behavior is the ant-like trails of robots following each other toward the target. If the robot is not in range of another robot that is either in range of the target or following another robot, the robot will assign-1 to its quality-of-information, and will execute an exhaustive search. The exhaustive search will continue until it encounters either the target or another robot with a nonnegative quality-of-information. The quality of information approach was extended to the case where each robot only has two-bit signals informing it of distance to in-range robots.
Modelling of temperatures in continental convergence zones
Toksoz, M.N.; Bird, P.
1977-08-03
The thermal histories of continent-continent convergence zones are modelled by a finite-difference technique in an attempt to explain geologic observations of heating and melting in such zones. The suture zone between two converging continents divides a passively heated overriding plate from a quiet continental margin which is suddenly deformed in the collision. Both regions may be metamorphosed and intruded. On the continental-shelf side where mountains are formed by underthrusting within the crust, it was found that adiabatic and radioactive heating are negligible during the orogeny. Shear-strain heating may raise the fault zones to about 500/sup 0/C. At higher temperatures, dislocation creep of crustal rocks would be expected from laboratory results. Even high crustal radioactivity will not produce melting in less than 40 m.y. Thus any plutons in this zone (the granites of the Zagros, Urals, and Himalayas) probably result indirectly by melting of crust that is heated by deep asthenospheric intrusions, which may reach the crust at the time of detachment of the oceanic slab, combined with the effects of friction and water along the subduction plane. Across the suture, the thermal history begins before the collision during the oceanic subduction phase. The sinking slab creates asthenospheric circulations, which warm the passive plate from below and intrude it in an Andean-type arc along the suture (Zagros and Himalayan region). If total subduction exceeds about 3000 km the slow warming has time to weaken the plate and extensive crustal shortening may follow the collision. Crustal shortening and thickening is accompanied by differentiation and volcanism (Tibetan and Grenville orogenies). Thermal modelling of Tibet shows that volcanism cannot be produced in the available time by crustal thickening alone, but requires the initial warming phase as well.
On A Rapidly Converging Series For The Riemann Zeta Function
Pichler, Alois
2012-01-01
To evaluate Riemann's zeta function is important for many investigations related to the area of number theory, and to have quickly converging series at hand in particular. We investigate a class of summation formulae and find, as a special case, a new proof of a rapidly converging series for the Riemann zeta function. The series converges in the entire complex plane, its rate of convergence being significantly faster than comparable representations, and so is a useful basis for evaluation algorithms. The evaluation of corresponding coefficients is not problematic, and precise convergence rates are elaborated in detail. The globally converging series obtained allow to reduce Riemann's hypothesis to similar properties on polynomials. And interestingly, Laguerre's polynomials form a kind of leitmotif through all sections.
Revisiting world energy intensity convergence for regional differences
Liddle, Brantley [Centre for Strategic Economic Studies, Victoria University, Melbourne, VIC 8001 (Australia)
2010-10-15
World convergence in energy intensity is revisited using two new large data sets: a 111-country sample spanning 1971-2006, and a 134-country sample spanning 1990-2006. Both data sets confirm continued convergence. However, the larger data set, which adds the former Soviet Union republics and additional Balkan countries, indicates greater convergence over its more recent time-frame. Further investigation of geographical differences reveals that the OECD and Eurasian countries have shown considerable, continued convergence, while the Sub-Saharan African countries have converged amongst themselves, but at a slower rate than the OECD and Eurasian countries; by contrast, Latin American and Caribbean and Middle East and North African countries have exhibited no convergence to divergence in energy intensity. (author)
On Ideal Convergence of Double Sequences in Probabilistic Normed Spaces
Vijay KUMAR; Bernardo LAFUERZA-GUILL(E)N
2012-01-01
The notion of ideal convergence is a generalization of statistical convergence which has been intensively investigated in last few years.For an admissible ideal ∮ (∈) N × N,the aim of the present paper is to introduce the concepts of ∮-convergence and ∮*-convergence for double sequences on probabilistic normed spaces (PN spaces for short).We give some relations related to these notions and find condition on the ideal ∮ for which both the notions coincide.We also define ∮-Cauchy and ∮*-Cauchy double sequences on PN spaces and show that ∮-convergent double sequences are ∮-Cauchy on these spaces.We establish example which shows that our method of convergence for double sequences on PN spaces is more general.
Gasdynamic characteristics of toroidal shock and detonation wave converging
TENG; Honghui; JIANG; Zonglin
2005-01-01
The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.
Exponential convergence rates for weighted sums in noncommutative probability space
Choi, Byoung Jin; Ji, Un Cig
2016-11-01
We study exponential convergence rates for weighted sums of successive independent random variables in a noncommutative probability space of which the weights are in a von Neumann algebra. Then we prove a noncommutative extension of the result for the exponential convergence rate by Baum, Katz and Read. As applications, we first study a large deviation type inequality for weighted sums in a noncommutative probability space, and secondly we study exponential convergence rates for weighted free additive convolution sums of probability measures.
Linear perturbations of a Schwarzschild blackhole by thin disc - convergence
Čížek, P.; Semerák, O.
2012-07-01
In order to find the perturbation of a Schwarzschild space-time due to a rotating thin disc, we try to adjust the method used by [4] in the case of perturbation by a one-dimensional ring. This involves solution of stationary axisymmetric Einstein's equations in terms of spherical-harmonic expansions whose convergence however turned out questionable in numerical examples. Here we show, analytically, that the series are almost everywhere convergent, but in some regions the convergence is not absolute.
Cosmological constraints from the convergence 1-point probability distribution
Patton, Kenneth; Blazek, Jonathan; Honscheid, Klaus; Huff, Eric; Melchior, Peter; Ross, Ashley J.; Suchyta, Eric
2016-01-01
We examine the cosmological information available from the 1-point probability distribution (PDF) of the weak-lensing convergence field, utilizing fast L-PICOLA simulations and a Fisher analysis. We find competitive constraints in the $\\Omega_m$-$\\sigma_8$ plane from the convergence PDF with $188\\ arcmin^2$ pixels compared to the cosmic shear power spectrum with an equivalent number of modes ($\\ell < 886$). The convergence PDF also partially breaks the degeneracy cosmic shear exhibits in that...
Moore-Smith Convergence in L-Fuzzifying Topological Spaces
Wei YAO; Ling Xia LU
2011-01-01
This paper presents a definition of L-fuzzifying nets and the related L-fuzzifying generalized convergence spaces.The Moore-Smith convergence is established in L-fuzzifying topology.It is shown that the category of L-fuzzifying generalized convergence spaces is a cartesianclosed topological category which embeds the category of L-fuzzifying topological spaces as a reflective subcategory.
Abscissas of weak convergence of vector valued Dirichlet series
2015-01-01
The abscissas of convergence, uniform convergence and absolute convergence of vector valued Dirichlet series with respect to the original topology and with respect to the weak topology $\\sigma(X,X')$ of a locally convex space $X$, in particular of a Banach space $X$, are compared. The relation of their coincidence with geometric or topological properties of the underlying space $X$ is investigated. Cotype in the context of Banach spaces, and nuclearity and certain topological invariants for F...
Strong Convergence of Stochastic Approximation Without Lyapunov Functions
1995-01-01
We prove convergence with probability one of a multivariate Markov stochastic approximation procedure of the Robbins-Monro type with several roots. The argument exploits convergence of the corresponding system of ordinary differential equations to its stationary points. If the points are either linearly stable or linearly unstable, we prove convergence with probability 1 of the procedure to a random vector whose distribution concentrates on the set of stable stationary points. This generalize...
A Convergent Iterative Algorithm for Solving Elastic Waveform Inversion
张剑锋
1994-01-01
The numerical method for elastic waveform inversion is studied and a convergent iterative algorithm is achieved by designing vinual source and altering objective function of the optimization solution in the computational process, which enables the solutions to converge to the real values and improves the convergence rate by changing the property of curved surface of the objective function, thus opening a new way for further developing the optimization solution of inverse problems.
O'Brien, Haley D; Faith, J Tyler; Jenkins, Kirsten E; Peppe, Daniel J; Plummer, Thomas W; Jacobs, Zenobia L; Li, Bo; Joannes-Boyau, Renaud; Price, Gilbert; Feng, Yue-Xing; Tryon, Christian A
2016-02-22
The fossil record provides tangible, historical evidence for the mode and operation of evolution across deep time. Striking patterns of convergence are some of the strongest examples of these operations, whereby, over time, similar environmental and/or behavioral pressures precipitate similarity in form and function between disparately related taxa. Here we present fossil evidence for an unexpected convergence between gregarious plant-eating mammals and dinosaurs. Recent excavations of Late Pleistocene deposits on Rusinga Island, Kenya, have uncovered a catastrophic assemblage of the wildebeest-like bovid Rusingoryx atopocranion. Previously known from fragmentary material, these new specimens reveal large, hollow, osseous nasal crests: a craniofacial novelty for mammals that is remarkably comparable to the nasal crests of lambeosaurine hadrosaur dinosaurs. Using adult and juvenile material from this assemblage, as well as computed tomographic imaging, we investigate this convergence from morphological, developmental, functional, and paleoenvironmental perspectives. Our detailed analyses reveal broad parallels between R. atopocranion and basal Lambeosaurinae, suggesting that osseous nasal crests may require a highly specific combination of ontogeny, evolution, and environmental pressures in order to develop. Copyright © 2016 Elsevier Ltd. All rights reserved.
SOME RESEARCHES ON WEAK CONVERGENCE OF KERGIN INTERPOLATION
Cui Lihong; Zhang Jielin; Liang Xuezhang
2005-01-01
The aim of this paper is to study the weak integral convergence of Kergin interpolation. The results of the weighted integral convergence and the weighted (partial) derivatives integral convergence of Kergin interpolation polynomial for the smooth functions on the unit disk were obtained in the paper. Those generalized Liang's main results were acquired in 1998 to the more extensive situation. At the same time, the estimation of convergence rate of Kergin interpolation polynomial is given by means of introducing a new kind of smooth norm.
Institutional and Socio-Economic Convergence in the European Union
Jordi López-Tamayo
2014-12-01
Full Text Available The objective of this paper is to analyze convergence in institutional, social, and macroeconomic conditions between EU member states. Our analysis covers the period 1995-2013 and considers the potential impact of the Great Recession. With this aim, we use a composite indicator that combines information from 51 hard and soft indicators, and we estimate convergence equations for the composite indicator and its seven dimensions considering different country groups. The obtained results show evidence of conditional convergence among EU member states but limited evidence of unconditional convergence over the considered period.
A hierarchical view of convergent evolution in microbial eukaryotes.
Leander, Brian S
2008-01-01
Distinguishing convergent evolution from other causes of similarity in organisms is necessary for reconstructing phylogenetic relationships, inferring patterns of character evolution, and investigating the forces of natural selection. In contrast to animals and land plants, the pervasiveness and adaptive significance of convergent evolution in microbes has yet to be systematically explored or articulated. Convergent evolution in microbial eukaryotes, for instance, often involves very distantly related lineages with relatively limited repertoires of morphological features. These large phylogenetic distances weaken the role of ancestral developmental programs on the subsequent evolution of morphological characters, making convergent evolution between very distantly related lineages fundamentally different from convergent evolution between closely related lineages. This suggests that examples of convergence at different levels in the phylogenetic hierarchy offer different clues about the causes and processes of macroevolutionary diversification. Accordingly (and despite opinions to the contrary), I recognize three broad and overlapping categories of phenotypic convergence-"parallel", "proximate" and "ultimate"-that represent either (1) subcellular analogues, (2) subcellular analogues to multicellular systems (and vice versa), or (3) multicellular analogues. Microbial eukaryotes living in planktonic environments, interstitial environments, and the intestinal environments of metazoan hosts provide compelling examples of ultimate convergence. After describing selected examples in microbial eukaryotes, I suggest some future directions needed to more fully understand the hierarchical structure of convergent evolution and the overall history of life.
Stability of Doob-Meyer Decomposition Under Extended Convergence
Jean Mémin
2003-01-01
In what follows, we consider the relation between Aldous's extended convergence and weak convergence of filtrations. We prove that, for a sequence (Xn) of Gnt)-special semimartingales, with canonicaldecomposition Xn = Mn + An, if the extended convergence (Xn, Fn) → (X, F.) holds with a quasi-left continuous (Ft)-special semimartingale X = M + A, then, under an additional assumption of uniform integrability,we get the convergence in probability under the Skorokhod topology: Mn →P M and An →P A.
Fractal aspects and convergence of Newton`s method
Drexler, M. [Oxford Univ. Computing Lab. (United Kingdom)
1996-12-31
Newton`s Method is a widely established iterative algorithm for solving non-linear systems. Its appeal lies in its great simplicity, easy generalization to multiple dimensions and a quadratic local convergence rate. Despite these features, little is known about its global behavior. In this paper, we will explain a seemingly random global convergence pattern using fractal concepts and show that the behavior of the residual is entirely explicable. We will also establish quantitative results for the convergence rates. Knowing the mechanism of fractal generation, we present a stabilization to the orthodox Newton method that remedies the fractal behavior and improves convergence.
Time dependent ethnic convergence in colorectal cancer survival in hawaii
Hundahl Scott A
2003-02-01
Full Text Available Abstract Background Although colorectal cancer death rates have been declining, this trend is not consistent across all ethnic groups. Biological, environmental, behavioral and socioeconomic explanations exist, but the reason for this discrepancy remains inconclusive. We examined the hypothesis that improved cancer screening across all ethnic groups will reduce ethnic differences in colorectal cancer survival. Methods Through the Hawaii Tumor Registry 16,424 patients diagnosed with colorectal cancer were identified during the years 1960–2000. Cox regression analyses were performed for each of three cohorts stratified by ethnicity (Caucasian, Japanese, Hawaiian, Filipino, and Chinese. The models included stage of diagnosis, year of diagnosis, age, and sex as predictors of survival. Results Mortality rates improved significantly for all ethnic groups. Moreover, with the exception of Hawaiians, rates for all ethnic groups converged over time. Persistently lower survival for Hawaiians appeared linked with more cancer treatment. Conclusion Ethnic disparities in colorectal cancer mortality rates appear primarily the result of differential utilization of health care. If modern screening procedures can be provided equally to all ethnic groups, ethnic outcome differences can be virtually eliminated.
Energy efficiency and social equity in South Africa: seeking convergence
Van Horen, C.; Simmonds, G. [University of Cape Town, Rondebosch (South Africa). Energy and Development Research Centre
1998-09-01
A key challenge facing post-apartheid South Africa is to achieve a balance between equity and efficiency goals. On the one hand, the democratic government wishes to improve the quality of life of the majority of the population, whilst on the other, the country needs an efficient and internationally competitive economy. At the more specific level of household energy policy, this efficiency-equity linkage represents a key challenge for policy-making and implementation: it is essential that convergence is sought between household energy strategies aimed at improving energy efficiency, and those strategies which improve the living conditions of the poor. This paper begins by reviewing developments in South Africa`s household energy sector in the early-1990s, most notably the national electrification plan which was launched in 1991. A second development, in 1994, was the establishment of the National Electricity Regulator. Despite the attention given to energy efficiency in the government`s new energy policy, energy efficiency considerations have not yet emerged as a major force in the energy sector. Electricity prices underestimated the environmental and other impacts of coal and nuclear-generated electricity. A range of economic and institutional reasons for this are identified and considered. Finally, two interventions on which some progress has been made, are described: these include insulation and thermal performance projects in new lost-cost houses, and a compact fluorescent lighting programme. 37 refs., 4 figs.
Khawam, Edward; Abiad, Bachir; Boughannam, Alaa; Saade, Joanna; Alameddine, Ramzi
2015-01-01
Great discrepancies are often encountered between the distance fixation and the near-fixation esodeviations and exodeviations. They are all attributed to either anomalies of the AC/A ratio or anomalies of the fusional convergence or divergence amplitudes. We report a case with pseudoconvergence insufficiency and another one with pseudoaccommodative convergence excess. In both cases, conv./div. excess and insufficiency were erroneously attributed to anomalies of the AC/A ratio or to anomalies of the fusional amplitudes. Our purpose is to show that numerous factors, other than anomalies in the AC/A ratio or anomalies in the fusional conv. or divergence amplitudes, can contaminate either the distance or the near deviations. This results in significant discrepancies between the distance and the near deviations despite a normal AC/A ratio and normal fusional amplitudes, leading to erroneous diagnoses and inappropriate treatment models.
Edward Khawam
2015-01-01
Full Text Available Great discrepancies are often encountered between the distance fixation and the near-fixation esodeviations and exodeviations. They are all attributed to either anomalies of the AC/A ratio or anomalies of the fusional convergence or divergence amplitudes. We report a case with pseudoconvergence insufficiency and another one with pseudoaccommodative convergence excess. In both cases, conv./div. excess and insufficiency were erroneously attributed to anomalies of the AC/A ratio or to anomalies of the fusional amplitudes. Our purpose is to show that numerous factors, other than anomalies in the AC/A ratio or anomalies in the fusional conv. or divergence amplitudes, can contaminate either the distance or the near deviations. This results in significant discrepancies between the distance and the near deviations despite a normal AC/A ratio and normal fusional amplitudes, leading to erroneous diagnoses and inappropriate treatment models.
Patel, Anil K.; Meeks, C.
1998-01-01
This paper discusses the application of Convergent Spray Technologies (TM) Spray Process to the development and successful implementation of Marshall Convergent Coating (MCC-1) as a primary Thermal Protection System (TPS) for the Space Shuttle Solid Rocket Boosters (SRBs). This paper discusses the environmental and process benefits of the MCC-1 technology, shows the systematic steps taken in developing the technology, including statistical sensitivity studies of about 35 variables. Based on the process and post-flight successes on the SRB, it will be seen that the technology is "field-proven". Application of this technology to other aerospace and commercial programs is summarized to illustrate the wide range of possibilities.
2013-01-01
With increasing numbers and quantities of chemicals in commerce and use, scientific attention continues to focus on the environmental and public health consequences of chemical production processes and exposures. Concerns about environmental stewardship have been gaining broader traction through emphases on sustainability and “green chemistry” principles. Occupational safety and health has not been fully promoted as a component of environmental sustainability. However, there is a natural convergence of green chemistry/sustainability and occupational safety and health efforts. Addressing both together can have a synergistic effect. Failure to promote this convergence could lead to increasing worker hazards and lack of support for sustainability efforts. The National Institute for Occupational Safety and Health has made a concerted effort involving multiple stakeholders to anticipate and identify potential hazards associated with sustainable practices and green jobs for workers. Examples of potential hazards are presented in case studies with suggested solutions such as implementing the hierarchy of controls and prevention through design principles in green chemistry and green building practices. Practical considerations and strategies for green chemistry, and environmental stewardship could benefit from the incorporation of occupational safety and health concepts which in turn protect affected workers. PMID:23587312
Schulte, Paul A; McKernan, Lauralynn T; Heidel, Donna S; Okun, Andrea H; Dotson, Gary Scott; Lentz, Thomas J; Geraci, Charles L; Heckel, Pamela E; Branche, Christine M
2013-04-15
With increasing numbers and quantities of chemicals in commerce and use, scientific attention continues to focus on the environmental and public health consequences of chemical production processes and exposures. Concerns about environmental stewardship have been gaining broader traction through emphases on sustainability and "green chemistry" principles. Occupational safety and health has not been fully promoted as a component of environmental sustainability. However, there is a natural convergence of green chemistry/sustainability and occupational safety and health efforts. Addressing both together can have a synergistic effect. Failure to promote this convergence could lead to increasing worker hazards and lack of support for sustainability efforts. The National Institute for Occupational Safety and Health has made a concerted effort involving multiple stakeholders to anticipate and identify potential hazards associated with sustainable practices and green jobs for workers. Examples of potential hazards are presented in case studies with suggested solutions such as implementing the hierarchy of controls and prevention through design principles in green chemistry and green building practices. Practical considerations and strategies for green chemistry, and environmental stewardship could benefit from the incorporation of occupational safety and health concepts which in turn protect affected workers.
Stayton, C Tristan
2015-08-01
Convergent evolution is an important phenomenon in the history of life. Despite this, there is no common definition of convergence used by biologists. Instead, several conceptually different definitions are employed. The primary dichotomy is between pattern-based definitions, where independently evolved similarity is sufficient for convergence, and process-based definitions, where convergence requires a certain process to produce this similarity. The unacknowledged diversity of definitions can lead to problems in evolutionary research. Process-based definitions may bias researchers away from studying or recognizing other sources of independently evolved similarity, or lead researchers to interpret convergent patterns as necessarily caused by a given process. Thus, pattern-based definitions are recommended. Existing measures of convergence are reviewed, and two new measures are developed. Both are pattern based and conceptually minimal, quantifying nothing but independently evolved similarity. One quantifies the amount of phenotypic distance between two lineages that is closed by subsequent evolution; the other simply counts the number of lineages entering a region of phenotypic space. The behavior of these measures is explored in simulations; both show acceptable Type I and Type II error. The study of convergent evolution will be facilitated if researchers are explicit about working definitions of convergence and adopt a standard toolbox of convergence measures. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.
Sustained fixation induced changes in phoria and convergence peak velocity.
Eun H Kim
Full Text Available PURPOSE: This study sought to investigate the influence of phoria adaptation on convergence peak velocity from responses located at different initial vergence positions. METHODS: Symmetrical 4° convergence step responses and near dissociated phoria (measured at 40 cm from the subject's midline were recorded from six subjects with normal binocular vision using an infrared limbus tracking system with a haploscope. Two different sustained fixations (1° and 16° convergent rotation along the subject's midline were used to study whether phoria had an influence on the peak velocity of convergence responses located at two initial vergence positions (1° or 'far' steps and 12° or 'near' steps. RESULTS: Phoria was significantly adapted after a sustained fixation task at near (16° and far (1° (p<0.002. A repeated measures ANOVA showed that convergence far steps were significantly faster than the near steps (p<0.03. When comparing convergence steps with the same initial vergence position, steps measured after near phoria adaptation were faster than responses after far adaptation (p<0.02. A regression analysis demonstrated that the change in phoria and the change in convergence peak velocity were significantly correlated for the far convergence steps (r = 0.97, p = 0.001. A weaker correlation was observed for the near convergence steps (r = 0.59, p = 0.20. CONCLUSION: As a result of sustained fixation, phoria was adapted and the peak velocity of the near and far convergence steps was modified. This study has clinical considerations since prisms, which evoke phoria adaptation, can be prescribed to help alleviate visual discomfort. Future investigations should include a systematic study of how prisms may influence convergence and divergence eye movements for those prescribed with prisms within their spectacles.
Genome-wide signatures of convergent evolution in echolocating mammals.
Parker, Joe; Tsagkogeorga, Georgia; Cotton, James A; Liu, Yuan; Provero, Paolo; Stupka, Elia; Rossiter, Stephen J
2013-10-10
Evolution is typically thought to proceed through divergence of genes, proteins and ultimately phenotypes. However, similar traits might also evolve convergently in unrelated taxa owing to similar selection pressures. Adaptive phenotypic convergence is widespread in nature, and recent results from several genes have suggested that this phenomenon is powerful enough to also drive recurrent evolution at the sequence level. Where homoplasious substitutions do occur these have long been considered the result of neutral processes. However, recent studies have demonstrated that adaptive convergent sequence evolution can be detected in vertebrates using statistical methods that model parallel evolution, although the extent to which sequence convergence between genera occurs across genomes is unknown. Here we analyse genomic sequence data in mammals that have independently evolved echolocation and show that convergence is not a rare process restricted to several loci but is instead widespread, continuously distributed and commonly driven by natural selection acting on a small number of sites per locus. Systematic analyses of convergent sequence evolution in 805,053 amino acids within 2,326 orthologous coding gene sequences compared across 22 mammals (including four newly sequenced bat genomes) revealed signatures consistent with convergence in nearly 200 loci. Strong and significant support for convergence among bats and the bottlenose dolphin was seen in numerous genes linked to hearing or deafness, consistent with an involvement in echolocation. Unexpectedly, we also found convergence in many genes linked to vision: the convergent signal of many sensory genes was robustly correlated with the strength of natural selection. This first attempt to detect genome-wide convergent sequence evolution across divergent taxa reveals the phenomenon to be much more pervasive than previously recognized.
Converging cylindrical shocks in ideal magnetohydrodynamics
Pullin, D. I.
2014-09-01
We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R = √μ0/p0 I/(2π) where I is the current, μ0 is the permeability, and p0 is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The diverging magnetic field then
Converging cylindrical shocks in ideal magnetohydrodynamics
Pullin, D. I.; Mostert, W.; Wheatley, V.; Samtaney, R.
2014-09-01
We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R=sqrt{μ _0/p_0} I/(2 π ) where I is the current, μ0 is the permeability, and p0 is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The diverging magnetic field
5G: The Convergence of Wireless Communications.
Chávez-Santiago, Raúl; Szydełko, Michał; Kliks, Adrian; Foukalas, Fotis; Haddad, Yoram; Nolan, Keith E; Kelly, Mark Y; Masonta, Moshe T; Balasingham, Ilangko
As the rollout of 4G mobile communication networks takes place, representatives of industry and academia have started to look into the technological developments toward the next generation (5G). Several research projects involving key international mobile network operators, infrastructure manufacturers, and academic institutions, have been launched recently to set the technological foundations of 5G. However, the architecture of future 5G systems, their performance, and mobile services to be provided have not been clearly defined. In this paper, we put forth the vision for 5G as the convergence of evolved versions of current cellular networks with other complementary radio access technologies. Therefore, 5G may not be a single radio access interface but rather a "network of networks". Evidently, the seamless integration of a variety of air interfaces, protocols, and frequency bands, requires paradigm shifts in the way networks cooperate and complement each other to deliver data rates of several Gigabits per second with end-to-end latency of a few milliseconds. We provide an overview of the key radio technologies that will play a key role in the realization of this vision for the next generation of mobile communication networks. We also introduce some of the research challenges that need to be addressed.
Convergence of Corporate and Public Governance
Gérard Hirigoyen
2013-06-01
Full Text Available By analyzing the differences between the corporate and public governance, theoretical and empirical research seems to indicate that the two domains of governance are far too different to share any common aspect. However, in this particular research, it has been argued that public governance is an application of corporate governance. Thus, the research question entails the description and analysis of this possible convergence of the two. Extensive research from literature on corporate governance has been undertaken to establish a relationship between the boards process and the roles that acts as a framework to bridge the gap separating corporate governance from public governance. Corporate governance, at a global level, exists in the for-profit as well as nonprofit organizations. Thus, the definition of this concept needs to be viewed from “an innovative” eye, considering the relationship between the process of the board and roles as characteristic of the public organization and private ones. As the private as well as public organizations are an application of corporate governance, the difference between the two gets narrowed. For the purpose of this research, the case of the French hospitals’ board has been taken into consideration. The members of the public board have been considered for the board process to perform their roles.
Convergent evolution of anti-bat sounds.
Corcoran, Aaron J; Hristov, Nickolay I
2014-09-01
Bats and their insect prey rely on acoustic sensing in predator prey encounters--echolocation in bats, tympanic hearing in moths. Some insects also emit sounds for bat defense. Here, we describe a previously unknown sound-producing organ in Geometrid moths--a prothoracic tymbal in the orange beggar moth (Eubaphe unicolor) that generates bursts of ultrasonic clicks in response to tactile stimulation and playback of a bat echolocation attack sequence. Using scanning electron microscopy and high-speed videography, we demonstrate that E. unicolor and phylogenetically distant tiger moths have evolved serially homologous thoracic tymbal organs with fundamentally similar functional morphology, a striking example of convergent evolution. We compared E. unicolor clicks to that of five sympatric tiger moths and found that 9 of 13 E. unicolor clicking parameters were within the range of sympatric tiger moths. Remaining differences may result from the small size of the E. unicolor tymbal. Four of the five sympatric clicking tiger moth species were unpalatable to bats (0-20% eaten), whereas E. unicolor was palatable to bats (86% eaten). Based on these results, we hypothesize that E. unicolor evolved tymbal organs that mimic the sounds produced by toxic tiger moths when attacked by echolocating bats.
Value Creation Through Integrated Networks and Convergence
De Martini, Paul; Taft, Jeffrey D.
2015-04-01
Customer adoption of distributed energy resources and public policies are driving changes in the uses of the distribution system. A system originally designed and built for one-way energy flows from central generating facilities to end-use customers is now experiencing injections of energy from customers anywhere on the grid and frequent reversals in the direction of energy flow. In response, regulators and utilities are re-thinking the design and operations of the grid to create more open and transactive electric networks. This evolution has the opportunity to unlock significant value for customers and utilities. Alternatively, failure to seize this potential may instead lead to an erosion of value if customers seek to defect and disconnect from the system. This paper will discuss how current grid modernization investments may be leveraged to create open networks that increase value through the interaction of intelligent devices on the grid and prosumerization of customers. Moreover, even greater value can be realized through the synergistic effects of convergence of multiple networks. This paper will highlight examples of the emerging nexus of non-electric networks with electricity.
Pollen and sperm heteromorphism: convergence across kingdoms?
Till-Bottraud, I; Joly, D; Lachaise, D; Snook, R R
2005-01-01
Sperm competition theory predicts that males should produce many, similar sperm. However, in some species of animals and plants, males exhibit a heteromorphism that results in the production of at least two different types of sperm or pollen grains. In animals, sperm heteromorphism typically corresponds to the production of one fertile morph and one (or more) sterile morph(s), whereas in plants two or more pollen morphs (one of which can be either sterile or fertile) are produced in all flowers but sometimes in different anthers. Heteromorphism has arisen independently several times across phyla and at different phylogenetic levels. Here, we compare and contrast sperm and pollen heteromorphism and discuss the evolutionary hypotheses suggested to explain heteromorphism in these taxa. These hypotheses include facilitation, nutritive contribution, blocking, cheap filler, sperm flushing or killing for animals; outcrossing and precise cross-pollen transfer or bet-hedging strategy for plants; cryptic female choice for both. We conclude that heteromorphism in the two phyla is most likely linked to a general evolutionary response to sexual selection, either to increase one male's sperm or pollen success in competition with other males, or mediate male/female interactions. Therefore, although sperm and pollen are not homologous, we suggest that heteromorphism represents an example of convergence across kingdoms.
Vergence adaptation in subjects with convergence excess.
Nilsson, Maria; Brautaset, Rune L
2011-03-01
The main purpose of this study was to evaluate the vergence adaptive ability in subjects diagnosed with convergence excess (CE) phoria (ie, subjects with an esophoric shift from distance to near but without an intermittent tropia at near). Vergence adaptation was measured at far and near with both base-in and base-out prisms using a "flashed" Maddox rod technique in 20 control subjects and 16 subjects with CE. In addition, accommodative adaptation and the stimulus AC/A and CA/C cross-links were measured. The AC/A and CA/C ratios were found to be high and low, respectively, and accommodative adaptation was found to be reduced in CE subjects as compared with the controls (P<0.005), all as predicted by the present theory. However, vergence adaptive ability was found to be reduced in the CE subjects at both distance and near and in response to both base-in and base-out prisms (P=0.002). This finding is not in accordance with and is difficult to reconcile with the present theory of CE.
Convergence and scatter of cluster density profiles
Diemand, J; Stadel, J; Diemand, Juerg; Moore, Ben; Stadel, Joachim
2004-01-01
We present new results from a series of $\\Lambda$CDM simulations of cluster mass halos resolved with high force and mass resolution. These results are compared with recently published simulations from groups using various codes including PKDGRAV, ART, TPM, GRAPE and GADGET. Careful resolution tests show that with 25 million particles within the high resolution region we can resolve to about 0.3\\% of the virial radius and that convergence in radius is proportional to the mean interparticle separation. The density profiles of 28 high resolution clusters obtained with the different codes and from different initial conditions agree very well. The average logarithmic slope at one percent of the virial radius is $\\gamma = 1.29$ with a scatter of $\\pm 0.16$ at all radii. Over the entire resolved regions the density profiles are well fitted by a smooth function that asymptotes to a central cusp $\\rho \\propto r^{-\\gamma}$, where we find $\\gamma=1.16\\pm 0.14$ from the mean of the fits to our six highest resolution clus...
Conformal mapping and convergence of Krylov iterations
Driscoll, T.A.; Trefethen, L.N. [Cornell Univ., Ithaca, NY (United States)
1994-12-31
Connections between conformal mapping and matrix iterations have been known for many years. The idea underlying these connections is as follows. Suppose the spectrum of a matrix or operator A is contained in a Jordan region E in the complex plane with 0 not an element of E. Let {phi}(z) denote a conformal map of the exterior of E onto the exterior of the unit disk, with {phi}{infinity} = {infinity}. Then 1/{vert_bar}{phi}(0){vert_bar} is an upper bound for the optimal asymptotic convergence factor of any Krylov subspace iteration. This idea can be made precise in various ways, depending on the matrix iterations, on whether A is finite or infinite dimensional, and on what bounds are assumed on the non-normality of A. This paper explores these connections for a variety of matrix examples, making use of a new MATLAB Schwarz-Christoffel Mapping Toolbox developed by the first author. Unlike the earlier Fortran Schwarz-Christoffel package SCPACK, the new toolbox computes exterior as well as interior Schwarz-Christoffel maps, making it easy to experiment with spectra that are not necessarily symmetric about an axis.
Influence of Role-Switching on Phonetic Convergence in Conversation
Pardo, Jennifer S.; Jay, Isabel Cajori; Hoshino, Risa; Hasbun, Sara Maria; Sowemimo-Coker, Chantal; Krauss, Robert M.
2013-01-01
The current study examined phonetic convergence when talkers alternated roles during conversational interaction. The talkers completed a map navigation task in which they alternated instruction Giver and Receiver roles across multiple map pairs. Previous studies found robust effects of the role of a talker on phonetic convergence, and it was…
Measuring Convergence using Dynamic Equilibrium Models: Evidence from Chinese Provinces
Pan, Lei; Posch, Olaf; van der Wel, Michel
We propose a model to study economic convergence in the tradition of neoclassical growth theory. We employ a novel stochastic set-up of the Solow (1956) model with shocks to both capital and labor. Our novel approach identifies the speed of convergence directly from estimating the parameters which...
Developing Administrative Law in Europe: Natural Convergence or imposed Uniformity?
Widdershoven, Rob
2014-01-01
In this contribution, the growing convergence between the administrative laws of the EU Member States and of the EU itself is discussed. Section 2 will deal with the top-down and bottom-up judge-made influences, which have already enhanced the process of convergence since the end of the fifties in t
Convergence analysis for column-action methods in image reconstruction
Elfving, Tommy; Hansen, Per Christian; Nikazad, Touraj
2016-01-01
. We present a convergence analysis of the column algorithms, we discuss two techniques (loping and flagging) for reducing the work, and we establish some convergence results for methods that utilize these techniques. The performance of the algorithms is illustrated with numerical examples from...
Dimensionality of civic participation in a convergent media environment
Ohme, Jakob; Albæk, Erik; de Vreese, Claes Holger
With the digitalization of information, subsequently leading to a fragmentation of audiences (Benett & Iyengar, 2008) and a change in the prevailing media logic (Schulz, 2014), a convergent media environment has developed. Nowadays, social media offer a platform for converging streams of informat...
On the premature convergence of particle swarm optimization
Larsen, Rie B.; Jouffroy, Jerome; Lassen, Benny
2016-01-01
This paper discusses convergence issues of the basic particle swarm optimization algorithm for different pa- rameters. For the one-dimensional case, it is shown that, for a specific range of parameters, the particles will converge prematurely, i.e. away from the actual minimum of the objective...
Thermal and mechanical modelling of convergent plate margins
van den Beukel, P.J.
1990-01-01
In this thesis, the thermal and mechanical structure of convergent plate margins will be investigated by means of numerical modelling. In addition, we will discuss the implications of modelling results for geological processes such as metamorphism or the break-up of a plate at a convergent plate
Compact Sets without Converging Sequences in the Random Real Model
D. Fremlin
2007-10-01
Full Text Available It is shown that in the model obtained by adding any number of random reals to a model of CH, there is a compact Hausdorff space of weight w1 which contains no non-trivial converging sequences. It is shown that for certain spaces with noconverging sequences, the addition of random reals will not add any converging sequences.
Convergence Rates of Finite Difference Stochastic Approximation Algorithms
2016-06-01
examine the rates of convergence for the Kiefer-Wolfowitz algorithm and the mirror descent algorithm , under various updating schemes using finite...dfferences as gradient approximations. It is shown that the convergence of these algorithms can be accelerated by controlling the implementation of the...Kiefer-Wolfowitz algorithm , mirror descent algorithm , finite-difference approximation, Monte Carlo methods REPORT DOCUMENTATION PAGE 11. SPONSOR
CONVERGENCE PROPERTIES OF THE DEPENDENT PRP CONJUGATE GRADIENT METHODS
Shujun LIAN; Changyu WANG; Lixia CAO
2006-01-01
In this paper, a new region of βκ with respect to βPRPκ is given. With two Armijo-type line searches, the authors investigate the global convergence properties of the dependent PRP conjugate gradient methods, which extend the global convergence results of PRP conjugate gradient method proved by Grippo and Lucidi (1997) and Dai and Yuan (2002).
EU Internet Law in the Era of Convergence
Jakobsen, Søren Sandfeld
2014-01-01
An analysis of the demarcation and interplay between EU's Internet, Telecoms and Media regulation in light of the growing convergence......An analysis of the demarcation and interplay between EU's Internet, Telecoms and Media regulation in light of the growing convergence...
Convergence of algorithms used for principal component analysis
张俊华; 陈翰馥
1997-01-01
The convergence of algorithms used for principal component analysis is analyzed. The algorithms are proved to converge to eigenvectors and eigenvalues of a matrix A which is the expectation of observed random samples. The conditions required here are considerably weaker than those used in previous work.
Ideal Convergence of k-Positive Linear Operators
Akif Gadjiev
2012-01-01
Full Text Available We study some ideal convergence results of k-positive linear operators defined on an appropriate subspace of the space of all analytic functions on a bounded simply connected domain in the complex plane. We also show that our approximation results with respect to ideal convergence are more general than the classical ones.
Influence of Role-Switching on Phonetic Convergence in Conversation
Pardo, Jennifer S.; Jay, Isabel Cajori; Hoshino, Risa; Hasbun, Sara Maria; Sowemimo-Coker, Chantal; Krauss, Robert M.
2013-01-01
The current study examined phonetic convergence when talkers alternated roles during conversational interaction. The talkers completed a map navigation task in which they alternated instruction Giver and Receiver roles across multiple map pairs. Previous studies found robust effects of the role of a talker on phonetic convergence, and it was…
ON CONVERGENCE OF MULTIGRID METHOD FOR NONNEGATIVE DEFINITE SYSTEMS
Qian-shun Chang; Wei-wei Sun
2005-01-01
In this paper, we consider multigrid methods for solving symmetric nonnegative definite matrix equations. We present some interesting features of the multigrid method and prove that the method is convergent in L2 space and the convergent solution is unique for such nonnegative definite system and given initial guess.
Convergence of adaptive finite element methods for eigenvalue problems
Garau, Eduardo M.; Morin, Pedro; Zuppa, Carlos
2008-01-01
In this article we prove convergence of adaptive finite element methods for second order elliptic eigenvalue problems. We consider Lagrange finite elements of any degree and prove convergence for simple as well as multiple eigenvalues under a minimal refinement of marked elements, for all reasonable marking strategies, and starting from any initial triangulation.
A note on the convergence of the direct collocation boundary
Juhl, Peter Møller
1998-01-01
An overview of the literature dealing with convergence of boundary element formulations is presented, and an intuitive account of the results is given. The convergence of an axisymmetric boundary element formulation is studied using linear, quadratic or superparametric elements. It is demonstrate...
Strong Convergence Properties for Asymptotically Almost Negatively Associated Sequence
Xueping Hu
2012-01-01
Full Text Available By applying the moment inequality for asymptotically almost negatively associated (in short AANA random sequence and truncated method, we get the three series theorems for AANA random variables. Moreover, a strong convergence property for the partial sums of AANA random sequence is obtained. In addition, we also study strong convergence property for weighted sums of AANA random sequence.
Thermal and mechanical modelling of convergent plate margins
van den Beukel, P.J.
1990-01-01
In this thesis, the thermal and mechanical structure of convergent plate margins will be investigated by means of numerical modelling. In addition, we will discuss the implications of modelling results for geological processes such as metamorphism or the break-up of a plate at a convergent plate mar
Confidence building on Euro convergence: evidence from currency options
Driessen, J.; Perotti, E.
2011-01-01
We study the evolution of investor confidence in 1992-1998 over the chance of individual currencies to converge to the Euro, using data on currency option prices. Convergence risk, which may reflect uncertainty over policy commitment as well as exogenous fundamentals, induces a level of implied vola
CONVERGENCE RATE OF A GENERALIZED ADDITIVE SCHWARZ ALGORITHM
Jin-ping Zeng; Gao-jie Chen
2006-01-01
The convergence rate of a generalized additive Schwarz algorithm for solving boundary value problems of elliptic partial differential equations is studied. A quantitative analysis of the convergence rate is given for the model Dirichlet problem. It will be shown that a greater acceleration of the algorithm can be obtained by choosing the parameter suitably.Some numerical tests are also presented in this paper.
Confidence building on Euro convergence: evidence from currency options
Driessen, J.; Perotti, E.
2011-01-01
We study the evolution of investor confidence in 1992-1998 over the chance of individual currencies to converge to the Euro, using data on currency option prices. Convergence risk, which may reflect uncertainty over policy commitment as well as exogenous fundamentals, induces a level of implied
Weak Convergence and Uniform Normalization in Infinitary Rewriting
Simonsen, Jakob Grue
2010-01-01
We study infinitary term rewriting systems containing finitely many rules. For these, we show that if a weakly convergent reduction is not strongly convergent, it contains a term that reduces to itself in one step (but the step itself need not be part of the reduction). Using this result, we prov...
Ω-CONVERGENCE AND Ω-COMPACTNESSOF THE TOPOLOGICAL SPACES
辛玉梅; 谢鸿政
2001-01-01
This paper defined Ω-convergence and Ω-compactness of the topological spaces, and gave some properties and equivalent form of the Ω-convergence and Ω-compactness. It also proved Ω-compactly topological spaces between countable compactly topological space and subset compactly topological spaces.
Convergence of p-series revisited with applications
Elom K. Abalo
2006-01-01
Full Text Available We construct two adjacent sequences that converge to the sum of a given convergent p-series. In case of a divergent p-series, lower and upper bounds of the (knth partial sum are constructed. In either case, we extend the results obtained by Hansheng and Lu (2005 to any integer k≥2. Some numerical examples are given.
Thermal and mechanical modelling of convergent plate margins
Beukel, P.J. van den
1990-01-01
In this thesis, the thermal and mechanical structure of convergent plate margins will be investigated by means of numerical modelling. In addition, we will discuss the implications of modelling results for geological processes such as metamorphism or the break-up of a plate at a convergent plate mar
Development of the Scale for "Convergence Thinking" in Engineering
Park, Sungmi
2016-01-01
Purpose: The purpose of this paper is to define the concept of "convergence thinking" as a trading zone for knowledge fusion in the engineering field, and develops its measuring scale. Design/ Methodology/Approach: Based on results from literature review, this study clarifies a theoretical ground for "convergence thinking."…
Are codes fostering convergence in corporate governance? An institutional perspective
Haxhi, I.; Aguilera, R.V.; Rasheed, A.A.; Yoshikawa, T.
2012-01-01
This chapter discusses the role of corporate governance codes in the context of pressures for corporate governance convergence across countries. We show that there is a diverging convergence as corporate governance practices continually evolve. Further, given that codes are non-mandatory in most cou
Convergent evolution as natural experiment: the tape of life reconsidered.
Powell, Russell; Mariscal, Carlos
2015-12-06
Stephen Jay Gould argued that replaying the 'tape of life' would result in radically different evolutionary outcomes. Recently, biologists and philosophers of science have paid increasing attention to the theoretical importance of convergent evolution-the independent origination of similar biological forms and functions-which many interpret as evidence against Gould's thesis. In this paper, we examine the evidentiary relevance of convergent evolution for the radical contingency debate. We show that under the right conditions, episodes of convergent evolution can constitute valid natural experiments that support inferences regarding the deep counterfactual stability of macroevolutionary outcomes. However, we argue that proponents of convergence have problematically lumped causally heterogeneous phenomena into a single evidentiary basket, in effect treating all convergent events as if they are of equivalent theoretical import. As a result, the 'critique from convergent evolution' fails to engage with key claims of the radical contingency thesis. To remedy this, we develop ways to break down the heterogeneous set of convergent events based on the nature of the generalizations they support. Adopting this more nuanced approach to convergent evolution allows us to differentiate iterated evolutionary outcomes that are probably common among alternative evolutionary histories and subject to law-like generalizations, from those that do little to undermine and may even support, the Gouldian view of life.
Photoacoustic-guided convergence of light through optically diffusive media.
Kong, Fanting; Silverman, Ronald H; Liu, Liping; Chitnis, Parag V; Lee, Kotik K; Chen, Y C
2011-06-01
We demonstrate that laser beams can be converged toward a light-absorbing target through optically diffusive media by using photoacoustic-guided interferometric focusing. The convergence of light is achieved by shaping the wavefront of the incident light with a deformable mirror to maximize the photoacoustic signal, which is proportional to the scattered light intensity at the light absorber.
On complete moment convergence for nonstationary negatively associated random variables
Mi-Hwa Ko
2016-05-01
Full Text Available Abstract The purpose of this paper is to establish the complete moment convergence for nonstationary negatively associated random variables satisfying the weak mean domination condition. The result is an improvement of complete convergence in Marcinkiewicz-Zygmund-type SLLN for negatively associated random variables in Kuczmaszewska (Acta Math. Hung. 128:116-130, 2010.
Weak convergence and uniform normalization in infinitary rewriting
Simonsen, Jakob Grue
2010-01-01
We study infinitary term rewriting systems containing finitely many rules. For these, we show that if a weakly convergent reduction is not strongly convergent, it contains a term that reduces to itself in one step (but the step itself need not be part of the reduction). Using this result, we prov...
Convergence Properties of Kemp's q-Binomial Distribution
Gerhold, Stefan; Zeiner, Martin
2008-01-01
We consider Kemp's q-analogue of the binomial distribution. Several convergence results involving the classical binomial, the Heine, the discrete normal, and the Poisson distribution are established. Some of them are q-analogues of classical convergence properties. Besides elementary estimates, we apply Mellin transform asymptotics.
A note on the convergence of the direct collocation boundary
Juhl, Peter Møller
1998-01-01
An overview of the literature dealing with convergence of boundary element formulations is presented, and an intuitive account of the results is given. The convergence of an axisymmetric boundary element formulation is studied using linear, quadratic or superparametric elements. It is demonstrate...
The analysis of the convergence of ant colony optimization algorithm
ZHU Qingbao; WANG Lingling
2007-01-01
The ant colony optimization algorithm has been widely studied and many important results have been obtained.Though this algorithm has been applied to many fields.the analysis about its convergence is much less,which will influence the improvement of this algorithm.Therefore,the convergence of this algorithm applied to the traveling salesman problem(TSP)was analyzed in detail.The conclusion that this algorithm will definitely converge to the optimal solution under the condition of 0＜q0＜1 was proved true.In addition,the influence on its convergence caused by the properties of the closed path,heuristic functions,the pheromone and q0 was analyzed.Based on the above-mentioned,some conclusions about how to improve the speed of its convergence are obtained.
Convergence of Romanian accounting regulations with IFRS. A longitudinal analysis
Ioana PĂLĂRIE
2016-06-01
Full Text Available In this paper we analyse the evolution in the level of convergence of the Romanian accounting regulations with IFRS in the last decade. We focus our study on the accounting topics covered by IAS16, IAS17, IAS 41 and SIC15. We find that in 2005 the regulations exhibit a good level of convergence for property, plant and equipment, a medium level of convergence for lease accounting and divergence for accounting for the agricultural activity. The overall convergence level improved over time for all the topics analysed. These results indicate that the companies with dual reporting may incur lower costs in applying IFRS. Moreover, the national regulations offer the opportunity for a higher level of comparability in Romania of the financial statements prepared under IFRS with those prepared under national regulations. However, we underline that the institutional factors (such as the tax influence over accounting might negatively affect the convergence of practices.
Convergence and Rate Analysis of Neural Networks for Sparse Approximation
Balavoine, Aurèle; Rozell, Christopher J
2011-01-01
We present an analysis of the Locally Competitive Algorithm (LCA), a Hopfield-style neural network that solves sparse approximation problems (e.g., approximating a vector from a dictionary using just a few non-zero coefficients). This class of problems plays a significant role in both theories of neural coding and applications in signal processing, but traditional analysis approaches are difficult because the objective functions are non-smooth. Specifically, we characterize the convergence properties of this system by showing that the LCA is globally convergent to a fixed point corresponding to the exact solution of the objective function, and (under some mild conditions) this solution is reached in finite time. Furthermore, we characterize the convergence rate of the system by showing that the LCA converges exponentially fast with an analytically bounded convergence rate (that depends on the specifics of a given problem). We support our analysis with several illustrative simulations.
Cosmic Reionization On Computers: Numerical and Physical Convergence
Gnedin, Nickolay Y
2016-01-01
In this paper I show that simulations of reionization performed under the Cosmic Reionization On Computers (CROC) project do converge in space and mass, albeit rather slowly. A fully converged solution (for a given star formation and feedback model) can be determined at a level of precision of about 20%, but such a solution is useless in practice, since achieving it in production-grade simulations would require a large set of runs at various mass and spatial resolutions, and computational resources for such an undertaking are not yet readily available. In order to make progress in the interim, I introduce a weak convergence correction factor in the star formation recipe, which allows one to approximate the fully converged solution with finite resolution simulations. The accuracy of weakly converged simulations approaches a comparable, ~20% level of precision for star formation histories of individual galactic halos and other galactic properties that are directly related to star formation rates, like stellar m...
On the Convergence of Iterative Receiver Algorithms Utilizing Hard Decisions
Jürgen F. Rößler
2009-01-01
Full Text Available The convergence of receivers performing iterative hard decision interference cancellation (IHDIC is analyzed in a general framework for ASK, PSK, and QAM constellations. We first give an overview of IHDIC algorithms known from the literature applied to linear modulation and DS-CDMA-based transmission systems and show the relation to Hopfield neural network theory. It is proven analytically that IHDIC with serial update scheme always converges to a stable state in the estimated values in course of iterations and that IHDIC with parallel update scheme converges to cycles of length 2. Additionally, we visualize the convergence behavior with the aid of convergence charts. Doing so, we give insight into possible errors occurring in IHDIC which turn out to be caused by locked error situations. The derived results can directly be applied to those iterative soft decision interference cancellation (ISDIC receivers whose soft decision functions approach hard decision functions in course of the iterations.
Convergence of Wachspress coordinates: from polygons to curved domains
Kosinka, Jiří
2014-08-08
Given a smooth, strictly convex planar domain, we investigate point-wise convergence of the sequence of Wachspress coordinates defined over finer and finer inscribed polygonal approximations of the domain. Based on a relation between the discrete Wachspress case and the limit smooth case given by the Wachspress kernel defined by Warren et al., we show that the corresponding sequences of Wachspress interpolants and mappings converge as 𝓞(h2) for a sampling step size h of the boundary curve of the domain as h → 0. Several examples are shown to numerically validate the results and to visualise the behaviour of discrete interpolants and mappings as they converge to their smooth counterparts. Empirically, the same convergence order is observed also for mean value coordinates. Moreover, our numerical tests suggest that the convergence of interpolants and mappings is uniform both in the Wachspress and mean value cases. © 2014 Springer Science+Business Media New York.
Some Implications for Regulation of ICT and Media Convergence
Henten, Anders; Falch, Morten; Tadayoni, Reza
The term convergence in the areas of ICT and media means the coming together of IT, telecommunications, broadcasting and other media, technologically, market and policy wise. It is the sectoral convergence of the hitherto more separate ICT and media areas, which is in focus, even though......, but also the reverse implications of policy and regulatory frameworks on technology and market developments. The paper analyses the convergence tendencies at a technological, market level and policy and regulatory level. It is, however, the policy level, which is the centre of attention in the paper....... The paper is intended to establish a useful framework for understanding convergence issues, raising questions and fostering discussion. Consequently, the outcome of the paper is not an firm conclusion putting forward a specific model for convergence regulation. It is rather a set of open questions...
Segment-specific adhesion as a driver of convergent extension.
Renske M A Vroomans
2015-02-01
Full Text Available Convergent extension, the simultaneous extension and narrowing of tissues, is a crucial event in the formation of the main body axis during embryonic development. It involves processes on multiple scales: the sub-cellular, cellular and tissue level, which interact via explicit or intrinsic feedback mechanisms. Computational modelling studies play an important role in unravelling the multiscale feedbacks underlying convergent extension. Convergent extension usually operates in tissue which has been patterned or is currently being patterned into distinct domains of gene expression. How such tissue patterns are maintained during the large scale tissue movements of convergent extension has thus far not been investigated. Intriguingly, experimental data indicate that in certain cases these tissue patterns may drive convergent extension rather than requiring safeguarding against convergent extension. Here we use a 2D Cellular Potts Model (CPM of a tissue prepatterned into segments, to show that convergent extension tends to disrupt this pre-existing segmental pattern. However, when cells preferentially adhere to cells of the same segment type, segment integrity is maintained without any reduction in tissue extension. Strikingly, we demonstrate that this segment-specific adhesion is by itself sufficient to drive convergent extension. Convergent extension is enhanced when we endow our in silico cells with persistence of motion, which in vivo would naturally follow from cytoskeletal dynamics. Finally, we extend our model to confirm the generality of our results. We demonstrate a similar effect of differential adhesion on convergent extension in tissues that can only extend in a single direction (as often occurs due to the inertia of the head region of the embryo, and in tissues prepatterned into a sequence of domains resulting in two opposing adhesive gradients, rather than alternating segments.
Divergent and Convergent Evolution of Fungal Pathogenicity.
Shang, Yanfang; Xiao, Guohua; Zheng, Peng; Cen, Kai; Zhan, Shuai; Wang, Chengshu
2016-05-12
Fungal pathogens of plants and animals have multifarious effects; they cause devastating damages to agricultures, lead to life-threatening diseases in humans, or induce beneficial effects by reducing insect pest populations. Many virulence factors have been determined in different fungal pathogens; however, the molecular determinants contributing to fungal host selection and adaptation are largely unknown. In this study, we sequenced the genomes of seven ascomycete insect pathogens and performed the genome-wide analyses of 33 species of filamentous ascomycete pathogenic fungi that infect insects (12 species), plants (12), and humans (9). Our results revealed that the genomes of plant pathogens encode more proteins and protein families than the insect and human pathogens. Unexpectedly, more common orthologous protein groups are shared between the insect and plant pathogens than between the two animal group pathogens. We also found that the pathogenicity of host-adapted fungi evolved multiple times, and that both divergent and convergent evolutions occurred during pathogen-host cospeciation thus resulting in protein families with similar features in each fungal group. However, the role of phylogenetic relatedness on the evolution of protein families and therefore pathotype formation could not be ruled out due to the effect of common ancestry. The evolutionary correlation analyses led to the identification of different protein families that correlated with alternate pathotypes. Particularly, the effector-like proteins identified in plant and animal pathogens were strongly linked to fungal host adaptation, suggesting the existence of similar gene-for-gene relationships in fungus-animal interactions that has not been established before. These results well advance our understanding of the evolution of fungal pathogenicity and the factors that contribute to fungal pathotype formation. © The Author 2016. Published by Oxford University Press on behalf of the Society for
Convergence phonétique en interaction Phonetic convergence in interaction
Lelong, Amélie
2012-01-01
The work presented in this manuscript is based on the study of a phenomenon called phonetic convergence which postulates that two people in interaction will tend to adapt how they talk to their partner in a communicative purpose. We have developed a paradigm called “Verbal Dominoes“ to collect a large corpus to characterize this phenomenon, the ultimate goal being to fill a conversational agent of this adaptability in order to improve the quality of human-machine interactions.We have done sev...
Financial Convergence Analysis: Implication for Insurance and Pension Markets
Natalia P. Kuznetsova
2016-06-01
Full Text Available The proposed paper is one of a set of articles dedicated to the new phenomenon in the global and national financial markets – financial convergence – and is focused on theoretical issues. The hypothesis of the article is to argue whether the financial convergence determines the directions of financial market (namely, insurance and pension sectors development. Adequately the goal of this paper is to analyze the existence of convergence processes in the insurance and pension markets. Methods of systematic and logical analysis are used. In the first part authors give brief history of the convergence phenomenon research. Then the paper analyses influence of financial convergence on insurance and pension markets, manifested in the following effects: mix of financial institutions functions; distribution channels advantages, increase of insurance and pension funds companies’ competitiveness; governance models convergence. The major results of the study are: demographic shifts in different developed and emerging markets countries caused the need to reform the social security systems and public pension schemes and refocus them to the market-based financial convergence model; pension funds, acting as institutional investors, are the leading players in the contemporary global financial market; competition at the financial market causes the expansion of a number of services offered by various organizations: banks, insurance companies, pension funds and so on, which offer a wide range of services not directly related to their core businesses; the mixing of financial institutions functions from the insurance, pension and banking sectors, increased competition for customers at the national and global financial market.
Turbulent boundary layer over a divergent convergent superhydrophobic surface
Jalalabadi, Razieh; Hwang, Jinyul; Nadeem, Muhammad; Yoon, Min; Sung, Hyung Jin
2017-08-01
A direct numerical simulation of a spatially developing turbulent boundary layer over a divergent and convergent superhydrophobic surface (SHS) was performed over the range 800 < Reθ < 1200. The surface patterns were aligned along the streamwise direction. The SHS was modeled as a pattern of free-slip and no-slip surfaces. The gas fraction of the divergent and convergent SHS was the same as that for the straight SHS for a given slip area. The divergent and convergent SHS gave 21% more drag reduction than the straight SHS. Although the maximum value of the streamwise slip velocity was larger over the divergent and convergent SHS, the average slip velocity (Uslip/U∞) was larger over the straight SHS. The greater drag reduction was attributed to the manipulation of the secondary flow in the y-z plane and the changes in the turbulence structure. The streamwise vortices generated by the secondary flow over the divergent and convergent SHS were diminished which reduced drag relative to the flow over the straight SHS. The ejection and sweep motions were weak, and the vortical structure was attenuated near the wall over the divergent and convergent SHS. The skin friction contributions were explored using the velocity-vorticity correlation. The vortex stretching contribution dominated the skin friction budget. The reduced skin friction over the divergent and convergent SHS resulted mainly from reduced vortex stretching.
Convergent evolution within an adaptive radiation of cichlid fishes.
Muschick, Moritz; Indermaur, Adrian; Salzburger, Walter
2012-12-18
The recurrent evolution of convergent forms is a widespread phenomenon in adaptive radiations (e.g., [1-9]). For example, similar ecotypes of anoles lizards have evolved on different islands of the Caribbean, benthic-limnetic species pairs of stickleback fish emerged repeatedly in postglacial lakes, equivalent sets of spider ecomorphs have arisen on Hawaiian islands, and a whole set of convergent species pairs of cichlid fishes evolved in East African Lakes Malawi and Tanganyika. In all these cases, convergent phenotypes originated in geographic isolation from each other. Recent theoretical models, however, predict that convergence should be common within species-rich communities, such as species assemblages resulting from adaptive radiations. Here, we present the most extensive quantitative analysis to date of an adaptive radiation of cichlid fishes, discovering multiple instances of convergence in body and trophic morphology. Moreover, we show that convergent morphologies are associated with adaptations to specific habitats and resources and that Lake Tanganyika's cichlid communities are characterized by the sympatric occurrence of convergent forms. This prevalent coexistence of distantly related yet ecomorphologically similar species offers an explanation for the greatly elevated species numbers in cichlid species flocks. Copyright © 2012 Elsevier Ltd. All rights reserved.
Convergência local de renda no Brasil
Erika Cristina Barbosa de Almeida Ribeiro
2012-09-01
Full Text Available Diversos trabalhos verificam a hipótese de convergência de renda para as regiões brasileiras. Contudo, a persistência da desigualdade de renda ainda é verificada entre as regiões. Nesse contexto, utilizando a metodologia de Regressões Ponderadas Geograficamente (RPG, o presente trabalho busca analisar a hipótese de convergência local para as áreas mínimas comparáveis (AMCs. Os principais resultados confirmam a hipótese de múltiplos equilíbrios. Entretanto, de maneira mais sofisticada que a análise de clubes de convergência, os resultados da análise local indicam que cada AMC estaria convergindo para o seu específico estado estacionário.Several works verify the hypothesis of income convergence for Brazilian regions. However, income inequality's persistence can still be verified. In this context, using the methodology of Geographically Weighted Regression (GWR, this study aims to analyze the local income convergence among the Brazilians areas (AMCs. The main results indicate multiple equilibria hypotheses. But, in a more sophisticated manner than convergence clubs analysis, local analysis results indicate that each AMC would be converging to its specific steady state.
Implementing Environmental Management Accounting: Status and Challenges
: Visualizing the Policy Challenges of Environmental Management Accounting; Dick Osborn. Section 2 Exploring EMA implementation issues. 6. Environmental Performance and the Quality of Corporate Environmental Reports: The Role of Environmental Management Accounting; Marcus Wagner. 7. Environmental Risk......Table of contents Preface. 1. Environmental Management Accounting: Innovation or Managerial Fad?; Pall Rikhardsson, Martin Bennett, Jan Jaap Bouma and Stefan Schaltegger. Section 1 Progress. 2. Challenges for Environmental Management Accounting; Roger L. Burritt 3. Current Trends in Environmental...... Cost Accounting - and its Interaction with Eco-Efficiency Performance Measurement and Indicators; Stefan Schaltegger and Marcus Wagner. 4. Environmental Accounting Dimensions: Pros and Cons of Trajectory Convergence and Increased Efficiency; Pontus Cerin and Staffan Laestadius. 5. Process and Content...
Collar, David C; Reece, Joshua S; Alfaro, Michael E; Wainwright, Peter C; Mehta, Rita S
2014-06-01
Convergence is central to the study of evolution because it demonstrates the power of natural selection to deterministically shape phenotypic diversity. However, the conditions under which a common morphology repeatedly evolves may be restrictive. Many factors, such as differing genetic and environmental backgrounds and many-to-one mapping of form to function, contribute to variability in responses to selection. Nevertheless, lineages may evolve similar, even if not identical, forms given a shared selective regime, providing opportunities to examine the relative importance of natural selection, constraint, and contingency. Here, we show that following 10 transitions to durophagy (eating hard-shelled prey) in moray eels (Muraenidae), cranial morphology repeatedly evolved toward a novel region of morphological space indicative of enhanced feeding performance on hard prey. Disparity among the resulting 15 durophagous species, however, is greater than disparity among ancestors that fed on large evasive prey, contradicting the pattern expected under convergence. This elevated disparity is a consequence of lineage-specific responses to durophagy, in which independent transitions vary in the suites of traits exhibiting the largest changes. Our results reveal a pattern of imperfect convergence, which suggests shared selection may actually promote diversification because lineages often differ in their phenotypic responses to similar selective demands.
Stochastic Convergence in Per Capita Carbon Dioxide (CO2 Emissions: Evidence from OECD Countries
Burcu OZCAN
2016-11-01
Full Text Available This study analyzes the validity of stochastic convergence hypothesis in relative per capita CO2 emissions in OECD (Organization for Economic Cooperation and Development countries for the period 1960-2013. In other words, it is aimed to reveal the nature of shocks to relative per capita CO2 emissions. As such, divergence holds if shocks are permanent, whereas convergence holds if shocks are temporary. To that aim, the two-break LM (Lagrange multiplier and three-step RALS-LM (residual augmented least squares Lagrange multiplier unit root tests are employed. The results mostly provide evidence of convergence in case of two breaks. However, when structural breaks are not taken into consideration, divergence gains empirical validity. From the viewpoint of government policy, these results indicate that energy usage or environmental protection policies of OECD countries have not long-run impacts on the relative per capita emissions series of the sample countries. Concerning the break dates, the first breaks mostly cumulated around the two energy crises period, whereas the second breaks generally occurred in the 1990s
SUPERLINEAR CONVERGENCE OF THE DFP ALGORITHM WITHOUT EXACT LINE SEARCH
濮定国
2001-01-01
@@ Broyden algorithms are very efficient methods for solving the nonlinear programming problem: min {f(x); x ∈ Rn}. (1) With exact line search, Powell[1] proved that the rate of convergence of these algorithms is one-step Q-superlinear for a twice continuously differentiable and uniformly convex function,and pu[2] extended this result for LC1 function. Pu and Yu[3] proved that if the points which are given by these algorithms are convergent they are globally convergent for continuously differentiable functions without convexity.
Convergence properties of the softassign quadratic assignment algorithm.
Rangarajan, A; Vuille, A; Mjolsness, E
1999-08-15
The softassign quadratic assignment algorithm is a discrete-time, continuous-state, synchronous updating optimizing neural network. While its effectiveness has been shown in the traveling salesman problem, graph matching, and graph partitioning in thousands of simulations, its convergence properties have not been studied. Here, we construct discrete-time Lyapunov functions for the cases of exact and approximate doubly stochastic constraint satisfaction, which show convergence to a fixed point. The combination of good convergence properties and experimental success makes the softassign algorithm an excellent choice for neural quadratic assignment optimization.
Semi-convergence properties of Kaczmarz’s method
Elfving, Tommy; Hansen, Per Christian; Nikazad, Touraj
2014-01-01
Kaczmarz’s method—sometimes referred to as the algebraic reconstruction technique—is an iterative method that is widely used in tomographic imaging due to its favorable semi-convergence properties. Specifically, when applied to a problem with noisy data, during the early iterations it converges......-convergence of Kaczmarz’s method as well as its projected counterpart (and their block versions). To do this we study how the data errors propagate into the iteration vectors and we derive upper bounds for this noise propagation. Our bounds are compared with numerical results obtained from tomographic imaging....
Rapidly converging multigrid reconstruction of cone-beam tomographic data
Myers, Glenn R.; Kingston, Andrew M.; Latham, Shane J.; Recur, Benoit; Li, Thomas; Turner, Michael L.; Beeching, Levi; Sheppard, Adrian P.
2016-10-01
In the context of large-angle cone-beam tomography (CBCT), we present a practical iterative reconstruction (IR) scheme designed for rapid convergence as required for large datasets. The robustness of the reconstruction is provided by the "space-filling" source trajectory along which the experimental data is collected. The speed of convergence is achieved by leveraging the highly isotropic nature of this trajectory to design an approximate deconvolution filter that serves as a pre-conditioner in a multi-grid scheme. We demonstrate this IR scheme for CBCT and compare convergence to that of more traditional techniques.
IS THERE CONVERGENCE ACROSS COUNTRIES? A SPATIAL APPROACH
Berry, Heather; Guillen, Mauro F.; Hendi, Arun S.
2014-01-01
We analyze convergence across countries over the last half century as a result of globalizing forces. Drawing on theories of modernization, dependency, the world-system, political trade blocs, and the world-society, we consider economic, demographic, knowledge, financial, and political dimensions of convergence. Using a new methodology, we calculate the minimum volume ellipsoid encompassing different groupings of countries, finding that during the 1960–2009 period, countries have not evolved significantly closer or similar to one another, although groups of countries based on their core-periphery status or membership in trade blocs exhibit increasing internal convergence and divergence between one another. PMID:25580035
Comparative Convergence Analysis of Nonlinear AMLI-Cycle Multigrid
Hu, Xiaozhe [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mathematics; Vassilevski, Panayot S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Xu, Jinchao [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mathematics
2013-04-30
The purpose of our paper is to provide a comprehensive convergence analysis of the nonlinear algebraic multilevel iteration (AMLI)-cycle multigrid (MG) method for symmetric positive definite problems. We show that the nonlinear AMLI-cycle MG method is uniformly convergent, based on classical assumptions for approximation and smoothing properties. Furthermore, under only the assumption that the smoother is convergent, we show that the nonlinear AMLI-cycle method is always better (or not worse) than the respective V-cycle MG method. Finally, numerical experiments are presented to illustrate the theoretical results.
Statistical Λ-Convergence in Probabilistic Normed Spaces
M. Aldhaifallah
2017-01-01
Full Text Available The main objective of the study was to understand the notion of Λ-convergence and to study the notion of probabilistic normed (PN spaces. The study has also aimed to define the statistical Λ-convergence and statistical Λ-Cauchy in PN-spaces. The concepts of these approaches have been defined by some examples, which have demonstrated the concepts of statistical Λ-convergence and statistical Λ-Cauchy in PN-spaces. Previous studies have also been used to understand similar terminologies and notations for the extraction of outcomes.
On the Convergence of Collaboration and Knowledge Management
yahia, Nesrine Ben; Ghézala, Henda Ben
2012-01-01
Collaboration technology typically focuses on collaboration and group processes (cooperation, communication, coordination and coproduction). Knowledge Management (KM) technology typically focuses on content (creation, storage, sharing and use of data, information and knowledge). Yet, to achieve their common goals, teams and organizations need both KM and collaboration technology to make that more effective and efficient. This paper is interested in knowledge management and collaboration regarding their convergence and their integration. First, it contributes to a better understanding of the knowledge management and collaboration concepts. Second, it focuses on KM and collaboration convergence by presenting the different interpretation of this convergence. Third, this paper proposes a generic framework of collaborative knowledge management.
Method-independent, Computationally Frugal Convergence Testing for Sensitivity Analysis Techniques
Mai, Juliane; Tolson, Bryan
2017-04-01
The increasing complexity and runtime of environmental models lead to the current situation that the calibration of all model parameters or the estimation of all of their uncertainty is often computationally infeasible. Hence, techniques to determine the sensitivity of model parameters are used to identify most important parameters or model processes. All subsequent model calibrations or uncertainty estimation procedures focus then only on these subsets of parameters and are hence less computational demanding. While the examination of the convergence of calibration and uncertainty methods is state-of-the-art, the convergence of the sensitivity methods is usually not checked. If any, bootstrapping of the sensitivity results is used to determine the reliability of the estimated indexes. Bootstrapping, however, might as well become computationally expensive in case of large model outputs and a high number of bootstraps. We, therefore, present a Model Variable Augmentation (MVA) approach to check the convergence of sensitivity indexes without performing any additional model run. This technique is method- and model-independent. It can be applied either during the sensitivity analysis (SA) or afterwards. The latter case enables the checking of already processed sensitivity indexes. To demonstrate the method independency of the convergence testing method, we applied it to three widely used, global SA methods: the screening method known as Morris method or Elementary Effects (Morris 1991, Campolongo et al., 2000), the variance-based Sobol' method (Solbol' 1993, Saltelli et al. 2010) and a derivative-based method known as Parameter Importance index (Goehler et al. 2013). The new convergence testing method is first scrutinized using 12 analytical benchmark functions (Cuntz & Mai et al. 2015) where the true indexes of aforementioned three methods are known. This proof of principle shows that the method reliably determines the uncertainty of the SA results when different
Henryka Langauer-Lewowicka 1
2016-06-01
Full Text Available The incidence of infantile autism due to developmental brain disorders has been permanently increasing in many parts of the world. Autism is characterized by impairments of communication and reciprocal social interaction and by restricted repetitive behaviours or interests. The causes of these disorders are not yet known. Experimental studies and clinical observation suggest that genetic and environmental factors could converge to result in neurotoxic mechanisms. These may lead to the development of autistic spectrum disorders (ASD. Several recent studies have indicated that perinatal exposure to environmental toxins may be the risk factor for ASD, among them: polybrominated diphenyl, esters, phthalates, bisphenol A, tetrabrombisphenol A, solvents, pesticides, and heavy metals. They can easily pass the placental and blood brain barriers and affect brain development.
Hillslope-scale experiment demonstrates role of convergence during two-step saturation
Gevaert, A. I.; Teuling, A. J.; Uijlenhoet, R.; DeLong, Stephen B.; Huxman, T. E.; Pangle, L. A.; Breshears, David D.; Chorover, J.; Pelletier, John D.; Saleska, S. R.; Zeng, X.; Troch, Peter A.
2014-01-01
Subsurface flow and storage dynamics at hillslope scale are difficult to ascertain, often in part due to a lack of sufficient high-resolution measurements and an incomplete understanding of boundary conditions, soil properties, and other environmental aspects. A continuous and extreme rainfall experiment on an artificial hillslope at Biosphere 2's Landscape Evolution Observatory (LEO) resulted in saturation excess overland flow and gully erosion in the convergent hillslope area. An array of 496 soil moisture sensors revealed a two-step saturation process. First, the downward movement of the wetting front brought soils to a relatively constant but still unsaturated moisture content. Second, soils were brought to saturated conditions from below in response to rising water tables. Convergent areas responded faster than upslope areas, due to contributions from lateral subsurface flow driven by the topography of the bottom boundary, which is comparable to impermeable bedrock in natural environments. This led to the formation of a groundwater ridge in the convergent area, triggering saturation excess runoff generation. This unique experiment demonstrates, at very high spatial and temporal resolution, the role of convergence on subsurface storage and flow dynamics. The results bring into question the representation of saturation excess overland flow in conceptual rainfall-runoff models and land-surface models, since flow is gravity-driven in many of these models and upper layers cannot become saturated from below. The results also provide a baseline to study the role of the co-evolution of ecological and hydrological processes in determining landscape water dynamics during future experiments in LEO.
Field convergence between technical writers and technical translators
Gnecchi, M.; Maylath, B.; Mousten, Birthe
2011-01-01
As translation of technical documents continues to grow rapidly and translation becomes more automated, the roles of professional communicators and translators appear to be converging. This paper updates preliminary findings first presented at the 2008 International Professional Communication...
Cosmological constraints from the convergence 1-point probability distribution
Patton, Kenneth; Honscheid, Klaus; Huff, Eric; Melchior, Peter; Ross, Ashley J; Suchyta, Eric
2016-01-01
We examine the cosmological information available from the 1-point probability distribution (PDF) of the weak-lensing convergence field, utilizing fast L-PICOLA simulations and a Fisher analysis. We find competitive constraints in the $\\Omega_m$-$\\sigma_8$ plane from the convergence PDF with $188\\ arcmin^2$ pixels compared to the cosmic shear power spectrum with an equivalent number of modes ($\\ell < 886$). The convergence PDF also partially breaks the degeneracy cosmic shear exhibits in that parameter space. A joint analysis of the convergence PDF and shear 2-point function also reduces the impact of shape measurement systematics, to which the PDF is less susceptible, and improves the total figure of merit by a factor of $2-3$, depending on the level of systematics. Finally, we present a correction factor necessary for calculating the unbiased Fisher information from finite differences using a limited number of cosmological simulations.
Convergence Analysis of a Class of Computational Intelligence Approaches
Junfeng Chen
2013-01-01
Full Text Available Computational intelligence approaches is a relatively new interdisciplinary field of research with many promising application areas. Although the computational intelligence approaches have gained huge popularity, it is difficult to analyze the convergence. In this paper, a computational model is built up for a class of computational intelligence approaches represented by the canonical forms of generic algorithms, ant colony optimization, and particle swarm optimization in order to describe the common features of these algorithms. And then, two quantification indices, that is, the variation rate and the progress rate, are defined, respectively, to indicate the variety and the optimality of the solution sets generated in the search process of the model. Moreover, we give four types of probabilistic convergence for the solution set updating sequences, and their relations are discussed. Finally, the sufficient conditions are derived for the almost sure weak convergence and the almost sure strong convergence of the model by introducing the martingale theory into the Markov chain analysis.
ON THE ROLE OF ECONOMIC HISTORY IN THE CONVERGENCE DEBATE
Michael W. Brandl
2000-01-01
Full Text Available For over a decade and a half macroeconomists who study economic growth have been embroiled in a debate over the issue of economic convergence. That is, for similar economies do poorer economies tend to catch-up to richer economies? The answer to the question goes to the very core of how economists explain economic growth. Macro theorists have developed scores of economic growth models to address this question. In addition, numerous econometric tests have been conducted attempting to answer this convergence question. Yet one group of economists that have not had much impact on this issue are economic historians. However when economic history is used to augment the theoretical and empirical investigations of the convergence question, the results can be striking. This paper seeks to stimulate economic historians interest in the convergence debate by illustrating the impact economic historical research can have on this important topic.
Strong Convergence of Modified Ishikawa Iterations for Nonlinear Mappings
Yongfu Su; Xiaolong Qin
2007-02-01
In this paper, we prove a strong convergence theorem of modified Ishikawa iterations for relatively asymptotically nonexpansive mappings in Banach space. Our results extend and improve the recent results by Nakajo, Takahashi, Kim, $Xu$, Matsushita and some others.
Convergent sequence evolution between echolocating bats and dolphins.
Liu, Yang; Cotton, James A; Shen, Bin; Han, Xiuqun; Rossiter, Stephen J; Zhang, Shuyi
2010-01-26
Cases of convergent evolution - where different lineages have evolved similar traits independently - are common and have proven central to our understanding of selection. Yet convincing examples of adaptive convergence at the sequence level are exceptionally rare [1]. The motor protein Prestin is expressed in mammalian outer hair cells (OHCs) and is thought to confer high frequency sensitivity and selectivity in the mammalian auditory system [2]. We previously reported that the Prestin gene has undergone sequence convergence among unrelated lineages of echolocating bat [3]. Here we report that this gene has also undergone convergent amino acid substitutions in echolocating dolphins, which group with echolocating bats in a phylogenetic tree of Prestin. Furthermore, we find evidence that these changes were driven by natural selection.
Convergence of the natural approximations of piecewise monotone interval maps.
Haydn, Nicolai
2004-06-01
We consider piecewise monotone interval mappings which are topologically mixing and satisfy the Markov property. It has previously been shown that the invariant densities of the natural approximations converge exponentially fast in uniform pointwise topology to the invariant density of the given map provided its derivative is piecewise Lipshitz continuous. We provide an example of a map which is Lipshitz continuous and for which the densities converge in the bounded variation norm at a logarithmic rate. This shows that in general one cannot expect exponential convergence in the bounded variation norm. Here we prove that if the derivative of the interval map is Holder continuous and its variation is well approximable (gamma-uniform variation for gamma>0), then the densities converge exponentially fast in the norm.
A cylindrical converging shock tube for shock-interface studies.
Luo, Xisheng; Si, Ting; Yang, Jiming; Zhai, Zhigang
2014-01-01
A shock tube facility for generating a cylindrical converging shock wave is developed in this work. Based on the shock dynamics theory, a specific wall profile is designed for the test section of the shock tube to transfer a planar shock into a cylindrical one. The shock front in the converging part obtained from experiment presents a perfect circular shape, which proves the feasibility and reliability of the method. The time variations of the shock strength obtained from numerical simulation, experiment, and theoretical estimation show the desired converging effect in the shock tube test section. Particular emphasis is then placed on the problem of shock-interface interaction induced by cylindrical converging shock waves. For this purpose, membrane-less gas cylinder is adopted to form the interface between two different fluids while the laser sheet technique to visualize the flow field. The result shows that it is convenient to perform such experiments in this facility.
Challenges and opportunities of convergence in building a knowledge economy
Jolliffe, B
2006-08-01
Full Text Available Slides include: What is the knowledge economy? Drivers; Will it contribute to development? Development as freedom; Knowledge Economy, ICTs, convergence etc; Ducks to put in a row; Patents and knowledge economy; South Africa? Threat to local...
Linearly convergent inexact proximal point algorithm for minimization. Revision 1
Zhu, C.
1993-08-01
In this paper, we propose a linearly convergent inexact PPA for minimization, where the inner loop stops when the relative reduction on the residue (defined as the objective value minus the optimal value) of the inner loop subproblem meets some preassigned constant. This inner loop stopping criterion can be achieved in a fixed number of iterations if the inner loop algorithm has a linear rate on the regularized subproblems. Therefore the algorithm is able to avoid the computationally expensive process of solving the inner loop subproblems exactly or asymptotically accurately; a process required by most of the other linearly convergent PPAs. As applications of this inexact PPA, we develop linearly convergent iteration schemes for minimizing functions with singular Hessian matrices, and for solving hemiquadratic extended linear-quadratic programming problems. We also prove that Correa-Lemarechal`s ``implementable form`` of PPA converges linearly under mild conditions.
Convergence results on iteration algorithms to linear systems.
Wang, Zhuande; Yang, Chuansheng; Yuan, Yubo
2014-01-01
In order to solve the large scale linear systems, backward and Jacobi iteration algorithms are employed. The convergence is the most important issue. In this paper, a unified backward iterative matrix is proposed. It shows that some well-known iterative algorithms can be deduced with it. The most important result is that the convergence results have been proved. Firstly, the spectral radius of the Jacobi iterative matrix is positive and the one of backward iterative matrix is strongly positive (lager than a positive constant). Secondly, the mentioned two iterations have the same convergence results (convergence or divergence simultaneously). Finally, some numerical experiments show that the proposed algorithms are correct and have the merit of backward methods.
Romania's Agriculture and its Role in the Convergence Process
CONSTANTIN POSTOIU
2015-05-01
Full Text Available The importance of agriculture in Romania is linked to the fact that 45% of its population is in the rural area, mostly dependent on agricultural activities. This paper aims to determine in what extent agriculture influences the convergence process of Romania with the euro area. The structural convergence index is computed in order to assess the degree in which the structure of the Romanian economy resembles the one of the euro area in terms of both gross value added and employment. Research indicates that Romania has the lowest score in terms of structural convergence with the euro area. The main reason is the oversized agricultural sector which employs almost a third of the active population. The productivity of the Romanian agriculture is then assessed in order to identify its possible effect on the country’s overall competitiveness and on the whole convergence process.
Convergence of posteriors for discretized log Gaussian Cox processes
Waagepetersen, Rasmus Plenge
2004-01-01
In Markov chain Monte Carlo posterior computation for log Gaussian Cox processes (LGCPs) a discretization of the continuously indexed Gaussian field is required. It is demonstrated that approximate posterior expectations computed from discretized LGCPs converge to the exact posterior expectations...
Total Factor Productivity Convergence in Africa: Panel Unit Root ...
PROF. O. E. OSUAGWU
2013-09-01
Sep 1, 2013 ... ... were made. Keywords: Total factor productivity, Convergence, Panel Unit Root. .... variable or labour quality variable. Mankiw et al [31] ... America are increasing in their economic growth rate ... This line of argument centers.
VERIFYING OF BETA CONVERGENCE FOR SOUTH EAST COUNTRIES OF ASIA
Michaela Blaško
2017-05-01
Full Text Available The convergence means the process of balancing disparities in chosen indicators of homogeneous economic groups. β-convergence and is based on the assumption, where less developed economy grows faster than advanced ones, so GDP per capita has higher speed in less developed economy. In this article is verified β convergence based on dependency between the growth of real GDP per capita and the initial level of real GDP per capita (in PPP and by modifications of this relationship by using of Least Squares Method for 9 countries of South East Asia in different samples since 2000 till 2015. For completely explanation of dependency and calculation of consistent, minimal estimator are used dummies and created a structural parameter, which eliminate shocks and possible disparities between chosen countries. Based on reached results was proved convergence just in sample since 2004 till 2008 between chosen nine countries of South East Countries of Asia.
Sensitivity Analysis and Statistical Convergence of a Saltating Particle Model
Maldonado, S
2016-01-01
Saltation models provide considerable insight into near-bed sediment transport. This paper outlines a simple, efficient numerical model of stochastic saltation, which is validated against previously published experimental data on saltation in a channel of nearly horizontal bed. Convergence tests are systematically applied to ensure the model is free from statistical errors emanating from the number of particle hops considered. Two criteria for statistical convergence are derived; according to the first criterion, at least $10^3$ hops appear to be necessary for convergent results, whereas $10^4$ saltations seem to be the minimum required in order to achieve statistical convergence in accordance with the second criterion. Two empirical formulae for lift force are considered: one dependent on the slip (relative) velocity of the particle multiplied by the vertical gradient of the horizontal flow velocity component; the other dependent on the difference between the squares of the slip velocity components at the to...
OPTIMAL CONVERGENCE RATE OF THE LANDAU EQUATION WITH FRICTIONAL FORCE
Liu Shuangqian; Liu Hongxia
2012-01-01
The Cauchy problem of the Landau equation with frictional force is investigated.Based on Fourier analysis and nonlinear energy estimates,the optimal convergence rate to the steady state is obtained under some conditions on initial data.
Converging technologies and de-perimeterisation: towards risky active insulation
Pieters, Wolter
In converging technologies (Roco and Bainbridge, 2003), boundaries between previously separated technologies become permeable. A similar process is also taking place within information technology. In what is called de-perimeterisation (Jericho Forum, 2005), the boundaries of the information
Learning by Investing, Embodiment, and Speed of Convergence
Groth, Christian; Wendner, Ronald
This paper sets up a dynamic general equilibrium model to study how the composition of technical progress affects the asymptotic speed of convergence. The following questions are addressed: Will endogenizing a fraction of the productivity increases as coming from learning by investing help...... to generate a low asymptotic speed of convergence in accordance with the empirical evidence? Does it matter whether learning originates in gross or net investment? The answers to both questions turn out to be: yes, a lot. The third question addressed is: Does the speed of convergence significantly depend...... on the degree to which learning by investing takes the embodied form rather than the disembodied form? The answer turns out to be: no. These results point to a speed of convergence on the small side of 2% per year and possibly tending to a lower level in the future due to the rising importance of investment...
Using Publicly Available Data to Anticipate Converging Industries
Curran, C.S.; Bröring, S.; Leker, J.
2010-01-01
Industry convergence, described as the blurring of boundaries between industries, plays an increasingly pivotal role in shaping markets and industries. Traditionally, this phenomenon has been discussed in respect to telecommunications, information technologies and electronics, but more recently also
Converging technologies and de-perimeterisation: towards risky active insulation
Pieters, W.
2009-01-01
In converging technologies (Roco and Bainbridge, 2003), boundaries between previously separated technologies become permeable. A similar process is also taking place within information technology. In what is called de-perimeterisation (Jericho Forum, 2005), the boundaries of the information infrastr
Convergent landscape. 39 and a half as (multi promotional intertext
Katarzyna Kopecka- Piech
2010-12-01
Full Text Available The purpose of this article is to provide a broader characterisation of the media convergence strategy applied by producers of the Polish commercial television station (TVN series 39 and a half (39 i pół. In order to examine the convergence strategies of production, distribution, promotion and media usage, this paper analyzes metaphors of landscape, terrain, map and simulacrum. Moreover the concept of convergent (intertext is proposed. In the case study of 39 and a half the author examines three main strategies implemented by the creators: the promotional virtualisation of reality, making virtual reality more real, and multiplied fiction. Transmedial and synergetic brands illustrate the hybridisation of the convergent and integrated media landscape.
On the Convergence of Broyden-Like Methods
Ioannis K. ARGYROS
2007-01-01
The author provides a finer local as well as semilocal convergence analysis of a certain class of Broyden-like methods for solving equations containing a nondifferentiable term on the m-dimensional Euclidean space (m≥1 a natural number).
Convergence to equilibrium in competitive Lotka-Volterra equations
Champagnat, Nicolas; Raoul, Gael
2010-01-01
We study a generalized system of ODE's modeling a finite number of biological populations in a competitive interaction. We adapt the techniques in two previous articles to prove the convergence to a unique stable equilibrium.
Using Publicly Available Data to Anticipate Converging Industries
Curran, C.S.; Bröring, S.; Leker, J.
2010-01-01
Industry convergence, described as the blurring of boundaries between industries, plays an increasingly pivotal role in shaping markets and industries. Traditionally, this phenomenon has been discussed in respect to telecommunications, information technologies and electronics, but more recently also
Beyond division: convergences between postmodern qualitative research and family therapy.
De Haene, Lucia
2010-01-01
Starting from examples of postmodern research and therapeutic practice, we raise the question on the role of the research-therapy dichotomy within these approaches. The article aims to show the profound convergence between postmodern ethnographic research and constructionist, collaborative therapeutic approaches on a double, epistemological and practice level. First, we point out their converging development toward narrative and constructionist epistemologies. Second, an inquiry into the core features of these disciplinary activities' goal, process, and expert role reveals their profound convergence into a dialogical practice in which the boundaries between research and therapy are radically transgressed. We conclude by questioning the implications and acceptability of this convergence for researchers' and therapists' understanding of their practices.
Effectiveness of vision therapy in school children with symptomatic convergence insufficiency
Jung Un Jang
2017-01-01
Conclusion: Among convergence insufficiency symptoms, the following improved in particular: near point of convergence, exophoria, and near positive fusional vergence. These findings suggest that vision therapy is very effective to recover from symptomatic convergence insufficiency.
Convergence of Composition Operators on Hardy-Smirnov Space
Xiang Dong YANG
2011-01-01
We consider the convergence of composition operators on Hardy-Smirnov space over a simply connected domain properly contained in the complex plane.The convergence of the power of a composition operator is also considered.Our approach is a method from Joel H.Shapiro and Wayne Smith's celebrated work (Journal of Functional Analysis 205 (2003) 62-89).The resulting space is usually not the one obtained from the classical Hardy space of the unit disc by conformal mapping.
Phonetic convergence in the speech of Polish learners of English
Zając, Magdalena
2015-01-01
This dissertation examines variability in the phonetic performance of L2 users of English and concentrates on speech convergence as a result of exposure to native and non-native pronunciation. The term speech convergence refers to a process during which speakers adapt their linguistic behaviour according to who they are talking or listening to. Previous studies show that the phenomenon may take place both in a speaker’s L1 (e.g. Giles, 1973; Coupland, 1984; Gregory and Webster,...
Sandwiched R\\'enyi Convergence for Quantum Evolutions
Müller-Hermes, Alexander; Franca, Daniel Stilck
2016-01-01
We study the speed of convergence of a primitive quantum time evolution towards its fixed point in the distance of sandwiched R\\'enyi divergences. For each of these distance measures the convergence is typically exponentially fast and the best exponent is given by a constant (similar to a logarithmic Sobolev constant) depending only on the generator of the time evolution. We establish relations between these constants and the logarithmic Sobolev constants as well as the spectral gap. An impor...
Generation of High Pressure and Temperature by Converging Detonation Waves
V. P. Singh
1987-07-01
Full Text Available Generation of high pressure and temperature has various applications in defence. Several techniques, viz flying plate method, collapsing of linear, convergence of detonation waves in solid explosives, have been established in this connection. In the present paper, converging detonation waves in solid explosives, where variable heat of detonation is being added to the front, is studied, by using Whitham's characteristics rule. Results are compared with those reported elsewhere.
Generation of High Pressure and Temperature by Converging Detonation Waves
Singh, V. P.; Shukla, S K
1987-01-01
Generation of high pressure and temperature has various applications in defence. Several techniques, viz flying plate method, collapsing of linear, convergence of detonation waves in solid explosives, have been established in this connection. In the present paper, converging detonation waves in solid explosives, where variable heat of detonation is being added to the front, is studied, by using Whitham's characteristics rule. Results are compared with those reported elsewhere.
Generation of high pressure and temperature by converging detonation waves
Singh, V. P.; Shukla, S. K.
1987-07-01
Generation of high pressure and temperature has various applications in defense. Several techniques, viz flying plate method, collapsing of linear, convergence of detonation waves in solid explosives, have been established in this connection. In this paper, converging detonation waves in solid explosives, where variable heat of detonation is being added to the front, are studied by using Whitham's characteristics rule. Results are compared with those reported elsewhere.
Bayesian Optimization Algorithm, Population Sizing, and Time to Convergence
Pelikan, M.; Goldberg, D.E.; Cantu-Paz, E.
2000-01-19
This paper analyzes convergence properties of the Bayesian optimization algorithm (BOA). It settles the BOA into the framework of problem decomposition used frequently in order to model and understand the behavior of simple genetic algorithms. The growth of the population size and the number of generations until convergence with respect to the size of a problem is theoretically analyzed. The theoretical results are supported by a number of experiments.
The Moment Convergence Rates for Largest Eigenvalues of β Ensembles
Jun Shan XIE
2013-01-01
The paper focuses on the largest eigenvalues of the β-Hermite ensemble and theβ-Laguerre ensemble.In particular,we obtain the precise moment convergence rates of their largest eigenvalues.The results are motivated by the complete convergence for partial sums of i.i.d.random variables,and the proofs depend on the small deviations for largest eigenvalues of the β ensembles and tail inequalities of the general β Tracy-Widom law.
A technique for accelerating the convergence of restarted GMRES
Baker, A H; Jessup, E R; Manteuffel, T
2004-03-09
We have observed that the residual vectors at the end of each restart cycle of restarted GMRES often alternate direction in a cyclic fashion, thereby slowing convergence. We present a new technique for accelerating the convergence of restarted GMRES by disrupting this alternating pattern. The new algorithm resembles a full conjugate gradient method with polynomial preconditioning, and its implementation requires minimal changes to the standard restarted GMRES algorithm.
CONVERGENCE ARTE FOR INTERATES OF q-BERNSTEIN POLYNOMIALS
无
2007-01-01
Recently, q-Bernstein polynomials have been intensively investigated by a number of authors. Their results show that for q ≠ 1, q-Bernstein polynomials possess of many interesting properties. In this paper, the convergence rate for iterates of both q-Bernstein when n →∞ and convergence rate of Bn(f,q;x) when f ∈ Cn-1[0, 1], q →∞ are also presented.
Tests of the 'Convergence Hypothesis': Some Further Results
Cohen, Daniel
1995-01-01
This paper offers new tests of the `convergence hypothesis'. It first analyses the pattern of growth of measured inputs (human and physical capital conventionally measured by an inventory method) and shows that these tests sustain the hypothesis. On the other hand, when the pattern of growth of revealed inputs (physical capital and Solow residual) is analysed, one is led to reject the convergence theory. In order to understand what lies at the heart of this discrepancy, the paper shows that t...
Convergence analysis of a proximal Gauss-Newton method
Salzo, Saverio
2011-01-01
An extension of the Gauss-Newton algorithm is proposed to find local minimizers of penalized nonlinear least squares problems, under generalized Lipschitz assumptions. Convergence results of local type are obtained, as well as an estimate of the radius of the convergence ball. Some applications for solving constrained nonlinear equations are discussed and the numerical performance of the method is assessed on some significant test problems.
Widespread convergence in toxin resistance by predictable molecular evolution
Ujvari, Beata; Casewell, Nicholas R.; Sunagar, Kartik; Arbuckle, Kevin; Wüster, Wolfgang; Lo, Nathan; O’Meally, Denis; Beckmann, Christa; King, Glenn F.; Deplazes, Evelyne; Madsen, Thomas
2015-01-01
Convergence has strong bearing on the fundamental debate about whether evolution is stochastic and unpredictable or subject to constraints. Here we show that, in certain circumstances, evolution can be highly predictable. We demonstrate that several lineages of insects, amphibians, reptiles, and mammals have utilized the same molecular solution, via the process of convergence, to evolve resistance to toxic cardiac glycosides produced defensively by plants and bufonid toads. The repeatability ...
Information technology convergence security, robotics, automations and communication
Barolli, Leonard; Xhafa, Fatos; Jeong, Hwa-Young
2013-01-01
Information technology and its convergence issue is emerging rapidly as an exciting new paradigm with user-centric environment to provide computing and communication services. This area will be the most comprehensive topics with various aspects of advances in information technology and its convergence services. This book covers all topics as computational science and applications, electronics engineering, manufacturing technology, services, technical skill to control the robot, automatic operation and application, simulation and testing communication and many more.
Convergence analysis of Strang splitting for Vlasov-type equations
Einkemmer, Lukas
2012-01-01
A rigorous convergence analysis of the Strang splitting algorithm for Vlasov-type equations in the setting of abstract evolution equations is provided. It is shown that under suitable assumptions the convergence is of second order in the time step h. As an example, it is verified that the Vlasov-Poisson equation in 1+1 dimensions fits into the framework of this analysis. Also, numerical experiments for the latter case are presented.
A convergent series for the QED effective action.
Cho, Y M; Pak, D G
2001-03-05
The one-loop effective action of QED obtained by Heisenberg and Euler and by Schwinger has been expressed by an asymptotic perturbative series which is divergent. In this Letter we present a nonperturbative but convergent series of the effective action. With the convergent series we establish the existence of the manifest electric-magnetic duality in the one-loop effective action of QED.
Complete Convergence for Weighted Sums of WOD Random Variables
ZHANG Ying; ZHANG Yu; SHEN Ai-ting
2016-01-01
In this article, we study the complete convergence for weighted sums of widely orthant dependent random variables. By using the exponential probability inequality, we establish a complete convergence result for weighted sums of widely orthant dependent ran-dom variables under mild conditions of weights and moments. The result obtained in the paper generalizes the corresponding ones for independent random variables and negatively dependent random variables.
Numerical Optimization of converging diverging miniature cavitating nozzles
Chavan, Kanchan; Bhingole, B.; Raut, J.; Pandit, A. B.
2015-12-01
The work focuses on the numerical optimization of converging diverging cavitating nozzles through nozzle dimensions and wall shape. The objective is to develop design rules for the geometry of cavitating nozzles for desired end-use. Two main aspects of nozzle design which affects the cavitation have been studied i.e. end dimensions of the geometry (i.e. angle and/or curvature of the inlet, outlet and the throat and the lengths of the converging and diverging sections) and wall curvatures(concave or convex). Angle of convergence at the inlet was found to control the cavity growth whereas angle of divergence of the exit controls the collapse of cavity. CFD simulations were carried out for the straight line converging and diverging sections by varying converging and diverging angles to study its effect on the collapse pressure generated by the cavity. Optimized geometry configurations were obtained on the basis of maximum Cavitational Efficacy Ratio (CER)i.e. cavity collapse pressure generated for a given permanent pressure drop across the system. With increasing capabilities in machining and fabrication, it is possible to exploit the effect of wall curvature to create nozzles with further increase in the CER. Effect of wall curvature has been studied for the straight, concave and convex shapes. Curvature has been varied and effect of concave and convex wall curvatures vis-à-vis straight walls studied for fixed converging and diverging angles.It is concluded that concave converging-diverging nozzles with converging angle of 20° and diverging angle of 5° with the radius of curvature 0.03 m and 0.1530 m respectively gives maximum CER. Preliminary experiments using optimized geometry are indicating similar trends and are currently being carried out. Refinements of the CFD technique using two phase flow simulations are planned.
A technique for accelerating the convergence of restarted GMRES
Baker, A H; Jessup, E R; Manteuffel, T
2004-03-09
We have observed that the residual vectors at the end of each restart cycle of restarted GMRES often alternate direction in a cyclic fashion, thereby slowing convergence. We present a new technique for accelerating the convergence of restarted GMRES by disrupting this alternating pattern. The new algorithm resembles a full conjugate gradient method with polynomial preconditioning, and its implementation requires minimal changes to the standard restarted GMRES algorithm.
Convergence clubs in cross-country life expectancy dynamics
Mayer-Foulkes, David
2001-01-01
I model life expectancy in terms of physical and human capital and technology, the fundamental economic variables described by economic growth theories. For concreteness, the Solow model and a convergence club growth model by Howitt and Mayer (2001) are used as examples. I discuss how a multiple convergence club structure can be used to define states of development and show that it must be reflected in the life expectancy dynamics. I then show by visual examination and by using mis-specificat...
COSMIC REIONIZATION ON COMPUTERS: NUMERICAL AND PHYSICAL CONVERGENCE
Gnedin, Nickolay Y., E-mail: gnedin@fnal.gov [Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States); Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States)
2016-04-10
In this paper I show that simulations of reionization performed under the Cosmic Reionization On Computers project do converge in space and mass, albeit rather slowly. A fully converged solution (for a given star formation and feedback model) can be determined at a level of precision of about 20%, but such a solution is useless in practice, since achieving it in production-grade simulations would require a large set of runs at various mass and spatial resolutions, and computational resources for such an undertaking are not yet readily available. In order to make progress in the interim, I introduce a weak convergence correction factor in the star formation recipe, which allows one to approximate the fully converged solution with finite-resolution simulations. The accuracy of weakly converged simulations approaches a comparable, ∼20% level of precision for star formation histories of individual galactic halos and other galactic properties that are directly related to star formation rates, such as stellar masses and metallicities. Yet other properties of model galaxies, for example, their H i masses, are recovered in the weakly converged runs only within a factor of 2.
Filopodial-Tension Model of Convergent-Extension of Tissues.
Julio M Belmonte
2016-06-01
Full Text Available In convergent-extension (CE, a planar-polarized epithelial tissue elongates (extends in-plane in one direction while shortening (converging in the perpendicular in-plane direction, with the cells both elongating and intercalating along the converging axis. CE occurs during the development of most multicellular organisms. Current CE models assume cell or tissue asymmetry, but neglect the preferential filopodial activity along the convergent axis observed in many tissues. We propose a cell-based CE model based on asymmetric filopodial tension forces between cells and investigate how cell-level filopodial interactions drive tissue-level CE. The final tissue geometry depends on the balance between external rounding forces and cell-intercalation traction. Filopodial-tension CE is robust to relatively high levels of planar cell polarity misalignment and to the presence of non-active cells. Addition of a simple mechanical feedback between cells fully rescues and even improves CE of tissues with high levels of polarity misalignments. Our model extends easily to three dimensions, with either one converging and two extending axes, or two converging and one extending axes, producing distinct tissue morphologies, as observed in vivo.
The IASB and FASB Convergence Process: Current Developments
Saher Aqel
2012-04-01
Full Text Available The importance of harmonization of accounting atandards is now widely accepted all over the world. The increased international movement of investments has strongly forces the harmonization of the various national accounting standards in a uniform financial reporting system accepted worldwide. Recently the Securities and Exchange Commission has agreed to remove the requirement international firms reporting under International Financial Reporting Standards (IFRS and listed in the U.S to provide reconciliation to U.S. Generally Accepted Accounting Principles (GAAP. This recent move of the Securities and Exchange Commission indicate that U.S. financial reporting is likely to converge with IFRS in the near future. The International Accounting Standards Board (IASB and the Financial Accounting Standards Board (FASB are currently working together so as to converge their existing accounting standards into a common set of international accounting standards. The objective of this paper is to discuss the FASB and IASB convergence process by addressing current developments regarding significant topics that were deemed critical to this convergence. The convergence of GAAP and IFRS seems inevitable. Mixed opinions have been voiced about this convergence process. Many have begun to consider obstacles that is possible to lay ahead as well as the possible costs and benefits of such a move to the IFRS .
Hungary: Political transformation and environmental challenge
O'Toole Jr, Laurence J.; Hanf, Kenneth
1998-01-01
Hungary is undergoing both radical economic transformation and political change. Presently a number of challenges converge and compete simultaneously for attention and resources. Hungarian environmental policy and administration are part and parcel of these changes and the competing demands they mak
Scenario Archetypes: Converging Rather than Diverging Themes
Jon P. Sadler
2012-04-01
Full Text Available Future scenarios provide challenging, plausible and relevant stories about how the future could unfold. Urban Futures (UF research has identified a substantial set (>450 of seemingly disparate scenarios published over the period 1997–2011 and within this research, a sub-set of >160 scenarios has been identified (and categorized based on their narratives according to the structure first proposed by the Global Scenario Group (GSG in 1997; three world types (Business as Usual, Barbarization, and Great Transitions and six scenarios, two for each world type (Policy Reform—PR, Market Forces—MF, Breakdown—B, Fortress World—FW, Eco-Communalism—EC and New Sustainability Paradigm—NSP. It is suggested that four of these scenario archetypes (MF, PR, NSP and FW are sufficiently distinct to facilitate active stakeholder engagement in futures thinking. Moreover they are accompanied by a well-established, internally consistent set of narratives that provide a deeper understanding of the key fundamental drivers (e.g., STEEP—Social, Technological, Economic, Environmental and Political that could bring about realistic world changes through a push or a pull effect. This is testament to the original concept of the GSG scenarios and their development and refinement over a 16 year period.
Svabo, Connie; Ekelund, Kathrine
2015-01-01
The philosophical subfield environmental aesthetics can contribute to the design of sustainable futures. Environmental aesthetics provides a conceptual framework for understanding the relationship between nature and culture. Current positions in environmental aesthetics are lined out and used...
Svabo, Connie; Lindelof, Anja Mølle
from the perspective of time and liveness as experienced in art on environmental performance discussing how environmental performances frame the temporality of the world. The paper engages with contemporary examples of environmental performances from various disciplines (sound, video, television...
Convergent transcription confers a bistable switch in Enterococcus faecalis conjugation.
Chatterjee, Anushree; Johnson, Christopher M; Shu, Che-Chi; Kaznessis, Yiannis N; Ramkrishna, Doraiswami; Dunny, Gary M; Hu, Wei-Shou
2011-06-07
Convergent gene pairs with head-to-head configurations are widespread in both eukaryotic and prokaryotic genomes and are speculated to be involved in gene regulation. Here we present a unique mechanism of gene regulation due to convergent transcription from the antagonistic prgX/prgQ operon in Enterococcus faecalis controlling conjugative transfer of the antibiotic resistance plasmid pCF10 from donor cells to recipient cells. Using mathematical modeling and experimentation, we demonstrate that convergent transcription in the prgX/prgQ operon endows the system with the properties of a robust genetic switch through premature termination of elongating transcripts due to collisions between RNA polymerases (RNAPs) transcribing from opposite directions and antisense regulation between complementary counter-transcripts. Evidence is provided for the presence of truncated RNAs resulting from convergent transcription from both the promoters that are capable of sense-antisense interactions. A mathematical model predicts that both RNAP collision and antisense regulation are essential for a robust bistable switch behavior in the control of conjugation initiation by prgX/prgQ operons. Moreover, given that convergent transcription is conserved across species, the mechanism of coupling RNAP collision and antisense interaction is likely to have a significant regulatory role in gene expression.
The Road to Convergence in Earthquake Frequency-Magnitude Statistics
Naylor, M.; Bell, A. F.; Main, I. G.
2013-12-01
The Gutenberg-Richter frequency-magnitude relation is a fundamental empirical law of seismology, but its form remains uncertain for rare extreme events. Convergence trends can be diagnostic of the nature of an underlying distribution and its sampling even before convergence has occurred. We examine the evolution of an information criteria metric applied to earthquake magnitude time series, in order to test whether the Gutenberg-Richter law can be rejecting in various earthquake catalogues. This would imply that the catalogue is starting to sample roll-off in the tail though it cannot yet identify the form of the roll-off. We compare bootstrapped synthetic Gutenberg-Richter and synthetic modified Gutenberg-Richter catalogues with the convergence trends observed in real earthquake data e.g. the global CMT catalogue, Southern California and mining/geothermal data. Whilst convergence in the tail remains some way off, we show that the temporal evolution of model likelihoods and parameters for the frequency-magnitude distribution of the global Harvard Centroid Moment Tensor catalogue is inconsistent with an unbounded GR relation, despite it being the preferred model at the current time. Bell, A. F., M. Naylor, and I. G. Main (2013), Convergence of the frequency-size distribution of global earthquakes, Geophys. Res. Lett., 40, 2585-2589, doi:10.1002/grl.50416.
Indirectly driven, high-convergence implosions (HEP1)
Hatchett, S.P.; Cable, M.D.; Caird, J.A. [and others
1996-06-01
High-gain inertial confinement fusion will most readily be achieved with hot-spot ignition, in which a relatively small mass of gaseous fuel at the center of the target is heated to 5-10 keV, igniting a larger surrounding mass of approximately isobaric fuel at higher density but lower temperature. Existing lasers are too low in energy to achieve thermonuclear gain, but hydrodynamically equivalent implosions using these lasers can demonstrate that the important, scalable parameters of ignition capsules are scientifically and technologically achievable. The experiments described in this article used gas-filled glass shells driven by x rays produced in a surrounding cavity, or hohlraum. These implosions achieved convergence ratios (initial capsule radius/ final fuel radius) high enough to fall in the range required for ignition-scale capsules, and they produced an imploded configuration (high-density glass with hot gas fill) that is equivalent to the hot-spot configuration of an ignition-scale capsule. Other recent laser-driven implosions have achieved high shell density but at lower convergences and without a well defined hot spot. Still other experiments have used very-low-density gas fill to reach high convergence with unshaped drive, but that approach results in a relatively low shell density. Moreover, even at the highest convergence ratios the implosions described here had neutron yields averaging 8% of that calculated for an idealized, clean, spherically symmetric implosion - much higher than previous high-convergence experiments.
Weak convergence theorems for a countable family of Lipschitzian mappings
Nilsrakoo, Weerayuth; Saejung, Satit
2009-08-01
This paper is concerned with convergence of an approximating common fixed point sequence of countable Lipschitzian mappings in a uniformly convex Banach space. We also establish weak convergence theorems for finding a common element of the set of fixed points, the set of solutions of an equilibrium problem, and the set of solutions of a variational inequality. With an appropriate setting, we obtain and improve the corresponding results recently proved by Moudafi [A. Moudafi, Weak convergence theorems for nonexpansive mappings and equilibrium problems. J. Nonlinear Convex Anal. 9 (2008) 37-43], Tada-Takahashi [A. Tada and W. Takahashi, Weak and strong convergence theorems for a nonexpansive mapping and an equilibrium problem. J. Optim. Theory Appl. 133 (2007) 359-370], and Plubtieng-Kumam [S. Plubtieng and P. Kumam, Weak convergence theorem for monotone mappings and a countable family of nonexpansive mappings. J. Comput. Appl. Math. (2008) doi:10.1016/j.cam.2008.05.045]. Some of our results are established with weaker assumptions.
Convergence of logistics planning and execution in outsourcing
Angela A. D’amato
2015-02-01
Full Text Available Background: Logistics service providers (LSPs are becoming increasingly involved in their clients’ businesses. Beyond just providing vehicles and buildings, LSPs are now becoming involved with knowledge-related work that is connected to the traditional services provided.Objectives: To investigate the likelihood and potential value of LSPs extending their range of services to their clients by means of a convergence of planning and execution activities.Method: In the research through a literature review and empirical study presented here, attention is given to the practical impact that convergence planning and execution functions have on business success, as well as how selected clients of an LSP (referred to in this article as logistics company A or LCA perceive the impact of increased integration of LCA within its businesses. The results should assist LCA and other LSPs considering the same objective to ascertain the opportunities and key requirements associated with a strategy to converge planning and execution activities for their clients.Results: The study found that the vast majority of respondents see value in the convergence of planning and execution activities.Conclusion: Such convergence will be challenging, owing to the importance of the planning function for clients, as well as key collaborative and measurement requirements that will have to be put in place for successful business integration.
Adaptive processes drive ecomorphological convergent evolution in antwrens (Thamnophilidae).
Bravo, Gustavo A; Remsen, J V; Brumfield, Robb T
2014-10-01
Phylogenetic niche conservatism (PNC) and convergence are contrasting evolutionary patterns that describe phenotypic similarity across independent lineages. Assessing whether and how adaptive processes give origin to these patterns represent a fundamental step toward understanding phenotypic evolution. Phylogenetic model-based approaches offer the opportunity not only to distinguish between PNC and convergence, but also to determine the extent that adaptive processes explain phenotypic similarity. The Myrmotherula complex in the Neotropical family Thamnophilidae is a polyphyletic group of sexually dimorphic small insectivorous forest birds that are relatively homogeneous in size and shape. Here, we integrate a comprehensive species-level molecular phylogeny of the Myrmotherula complex with morphometric and ecological data within a comparative framework to test whether phenotypic similarity is described by a pattern of PNC or convergence, and to identify evolutionary mechanisms underlying body size and shape evolution. We show that antwrens in the Myrmotherula complex represent distantly related clades that exhibit adaptive convergent evolution in body size and divergent evolution in body shape. Phenotypic similarity in the group is primarily driven by their tendency to converge toward smaller body sizes. Differences in body size and shape across lineages are associated to ecological and behavioral factors. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.
Evolution of parasitism along convergent lines: from ecology to genomics.
Poulin, Robert; Randhawa, Haseeb S
2015-02-01
SUMMARY From hundreds of independent transitions from a free-living existence to a parasitic mode of life, separate parasite lineages have converged over evolutionary time to share traits and exploit their hosts in similar ways. Here, we first summarize the evidence that, at a phenotypic level, eukaryotic parasite lineages have all converged toward only six general parasitic strategies: parasitoid, parasitic castrator, directly transmitted parasite, trophically transmitted parasite, vector-transmitted parasite or micropredator. We argue that these strategies represent adaptive peaks, with the similarities among unrelated taxa within any strategy extending to all basic aspects of host exploitation and transmission among hosts and transcending phylogenetic boundaries. Then, we extend our examination of convergent patterns by looking at the evolution of parasite genomes. Despite the limited taxonomic coverage of sequenced parasite genomes currently available, we find some evidence of parallel evolution among unrelated parasite taxa with respect to genome reduction or compaction, and gene losses or gains. Matching such changes in parasite genomes with the broad phenotypic traits that define the convergence of parasites toward only six strategies of host exploitation is not possible at present. Nevertheless, as more parasite genomes become available, we may be able to detect clear trends in the evolution of parasitic genome architectures representing true convergent adaptive peaks, the genomic equivalents of the phenotypic strategies used by all parasites.
Short-term time step convergence in a climate model.
Wan, Hui; Rasch, Philip J; Taylor, Mark A; Jablonowski, Christiane
2015-03-01
This paper evaluates the numerical convergence of very short (1 h) simulations carried out with a spectral-element (SE) configuration of the Community Atmosphere Model version 5 (CAM5). While the horizontal grid spacing is fixed at approximately 110 km, the process-coupling time step is varied between 1800 and 1 s to reveal the convergence rate with respect to the temporal resolution. Special attention is paid to the behavior of the parameterized subgrid-scale physics. First, a dynamical core test with reduced dynamics time steps is presented. The results demonstrate that the experimental setup is able to correctly assess the convergence rate of the discrete solutions to the adiabatic equations of atmospheric motion. Second, results from full-physics CAM5 simulations with reduced physics and dynamics time steps are discussed. It is shown that the convergence rate is 0.4-considerably slower than the expected rate of 1.0. Sensitivity experiments indicate that, among the various subgrid-scale physical parameterizations, the stratiform cloud schemes are associated with the largest time-stepping errors, and are the primary cause of slow time step convergence. While the details of our findings are model specific, the general test procedure is applicable to any atmospheric general circulation model. The need for more accurate numerical treatments of physical parameterizations, especially the representation of stratiform clouds, is likely common in many models. The suggested test technique can help quantify the time-stepping errors and identify the related model sensitivities.
Independent Molecular Basis of Convergent Highland Adaptation in Maize
Takuno, Shohei; Ralph, Peter; Swarts, Kelly; Elshire, Rob J.; Glaubitz, Jeffrey C.; Buckler, Edward S.; Hufford, Matthew B.; Ross-Ibarra, Jeffrey
2015-01-01
Convergent evolution is the independent evolution of similar traits in different species or lineages of the same species; this often is a result of adaptation to similar environments, a process referred to as convergent adaptation. We investigate here the molecular basis of convergent adaptation in maize to highland climates in Mesoamerica and South America, using genome-wide SNP data. Taking advantage of archaeological data on the arrival of maize to the highlands, we infer demographic models for both populations, identifying evidence of a strong bottleneck and rapid expansion in South America. We use these models to then identify loci showing an excess of differentiation as a means of identifying putative targets of natural selection and compare our results to expectations from recently developed theory on convergent adaptation. Consistent with predictions across a wide parameter space, we see limited evidence for convergent evolution at the nucleotide level in spite of strong similarities in overall phenotypes. Instead, we show that selection appears to have predominantly acted on standing genetic variation and that introgression from wild teosinte populations appears to have played a role in highland adaptation in Mexican maize. PMID:26078279
Berens, Ali J; Hunt, James H; Toth, Amy L
2015-03-01
An area of great interest in evolutionary genomics is whether convergently evolved traits are the result of convergent molecular mechanisms. The presence of queen and worker castes in insect societies is a spectacular example of convergent evolution and phenotypic plasticity. Multiple insect lineages have evolved environmentally induced alternative castes. Given multiple origins of eusociality in Hymenoptera (bees, ants, and wasps), it has been proposed that insect castes evolved from common genetic "toolkits" consisting of deeply conserved genes. Here, we combine data from previously published studies on fire ants and honey bees with new data for Polistes metricus paper wasps to assess the toolkit idea by presenting the first comparative transcriptome-wide analysis of caste determination among three major hymenopteran social lineages. Overall, we found few shared caste differentially expressed transcripts across the three social lineages. However, there is substantially more overlap at the levels of pathways and biological functions. Thus, there are shared elements but not on the level of specific genes. Instead, the toolkit appears to be relatively "loose," that is, different lineages show convergent molecular evolution involving similar metabolic pathways and molecular functions but not the exact same genes. Additionally, our paper wasp data do not support a complementary hypothesis that "novel" taxonomically restricted genes are related to caste differences. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Convergence of AMR and SPH simulations - I. Hydrodynamical resolution and convergence tests
Hubber, D A; Goodwin, S P
2013-01-01
We compare the results for a set of hydrodynamical tests performed with the AMR finite volume code, MG and the SPH code, SEREN. The test suite includes shock tube tests, with and without cooling, the non-linear thin-shell instability and the Kelvin-Helmholtz instability. The main conclusions are : (i) the two methods converge in the limit of high resolution and accuracy in most cases. All tests show good agreement when numerical effects (e.g. discontinuities in SPH) are properly treated. (ii) Both methods can capture adiabatic shocks and well-resolved cooling shocks perfectly well with standard prescriptions. However, they both have problems when dealing with under-resolved cooling shocks, or strictly isothermal shocks, at high Mach numbers. The finite volume code only works well at 1st order and even then requires some additional artificial viscosity. SPH requires either a larger value of the artificial viscosity parameter, alpha_AV, or a modified form of the standard artificial viscosity term using the harm...
Convergent evolution of vocal cooperation without convergent evolution of brain size.
Borjon, Jeremy I; Ghazanfar, Asif A
2014-01-01
One pragmatic underlying successful vocal communication is the ability to take turns. Taking turns - a form of cooperation - facilitates the transmission of signals by reducing the amount of their overlap. This allows vocalizations to be better heard. Until recently, non-human primates were not thought of as particularly cooperative, especially in the vocal domain. We recently demonstrated that common marmosets (Callithrix jacchus), a small New World primate species, take turns when they exchange vocalizations with both related and unrelated conspecifics. As the common marmoset is distantly related to humans (and there is no documented evidence that Old World primates exhibit vocal turn taking), we argue that this ability arose as an instance of convergent evolution, and is part of a suite of prosocial behavioral tendencies. Such behaviors seem to be, at least in part, the outcome of the cooperative breeding strategy adopted by both humans and marmosets. Importantly, this suite of shared behaviors occurs without correspondence in encephalization. Marmoset vocal turn taking demonstrates that a large brain size and complex cognitive machinery is not needed for vocal cooperation to occur. Consistent with this idea, the temporal structure of marmoset vocal exchanges can be described in terms of coupled oscillator dynamics, similar to quantitative descriptions of human conversations. We propose a simple neural circuit mechanism that may account for these dynamics and, at its core, involves vocalization-induced reductions of arousal. Such a mechanism may underlie the evolution of vocal turn taking in both marmoset monkeys and humans. © 2014 S. Karger AG, Basel.
Convergent series for lattice models with polynomial interactions
Ivanov, Aleksandr S.; Sazonov, Vasily K.
2017-01-01
The standard perturbative weak-coupling expansions in lattice models are asymptotic. The reason for this is hidden in the incorrect interchange of the summation and integration. However, substituting the Gaussian initial approximation of the perturbative expansions by a certain interacting model or regularizing original lattice integrals, one can construct desired convergent series. In this paper we develop methods, which are based on the joint and separate utilization of the regularization and new initial approximation. We prove, that the convergent series exist and can be expressed as re-summed standard perturbation theory for any model on the finite lattice with the polynomial interaction of even degree. We discuss properties of such series and study their applicability to practical computations on the example of the lattice ϕ4-model. We calculate expectation value using the convergent series, the comparison of the results with the Borel re-summation and Monte Carlo simulations shows a good agreement between all these methods.
A fast algorithm for nonnegative matrix factorization and its convergence.
Li, Li-Xin; Wu, Lin; Zhang, Hui-Sheng; Wu, Fang-Xiang
2014-10-01
Nonnegative matrix factorization (NMF) has recently become a very popular unsupervised learning method because of its representational properties of factors and simple multiplicative update algorithms for solving the NMF. However, for the common NMF approach of minimizing the Euclidean distance between approximate and true values, the convergence of multiplicative update algorithms has not been well resolved. This paper first discusses the convergence of existing multiplicative update algorithms. We then propose a new multiplicative update algorithm for minimizing the Euclidean distance between approximate and true values. Based on the optimization principle and the auxiliary function method, we prove that our new algorithm not only converges to a stationary point, but also does faster than existing ones. To verify our theoretical results, the experiments on three data sets have been conducted by comparing our proposed algorithm with other existing methods.
Romania’s Accession to Second Modernity. Potential of Convergence
Marin Dinu
2006-06-01
Full Text Available This paper analyses Romanian economy facing with European integration process at 2007. The Romanian economy advanced the development prudent macroeconomics policies and implement structural reforms in the market for goods, labor and financial products. We identify in this study the principal conditionalities for the admittance in European Union. The nominal and real convergence must be touched faster because this process supposes stability prices, the financial soundness indicators, the need to stabilize exchange rate. In addition, the real convergence with European Union is very important. First, we analyze the strategic errors of the Romanian authorities in transition period. Second, our study focuses on current challenges and makes suggestions for change the modernization process. Can Romanian economy obtain a grow faster convergence? Is the strategy of Romanian economy optimal?
Optimization and Convergence of Observation Channels in Stochastic Control
Yüksel, Serdar
2010-01-01
This paper studies the optimization of observation channels (stochastic kernels) in partially observed stochastic control problems. In particular, existence, continuity, and convexity properties are investigated. Continuity properties of the optimal cost in channels are explored under total variation, setwise convergence and weak convergence. Sufficient conditions for sequential compactness under total variation and setwise convergence are presented. It is shown that the optimization is concave in observation channels. This implies that the optimization problem is non-convex in quantization/coding policies for a class of networked control problems. Applications in optimal quantizer/coder design and robust control are presented, where new results on the existence of optimal quantizers are obtained. Furthermore, the paper explains why a class of decentralized control problems, under the non-classical information structure, is non-convex when {\\em signaling} is present. Finally, empirical con sistency of a class...
Sliding mode control method having terminal convergence in finite time
Venkataraman, Subramanian T. (Inventor); Gulati, Sandeep (Inventor)
1994-01-01
An object of this invention is to provide robust nonlinear controllers for robotic operations in unstructured environments based upon a new class of closed loop sliding control methods, sometimes denoted terminal sliders, where the new class will enforce closed-loop control convergence to equilibrium in finite time. Improved performance results from the elimination of high frequency control switching previously employed for robustness to parametric uncertainties. Improved performance also results from the dependence of terminal slider stability upon the rate of change of uncertainties over the sliding surface rather than the magnitude of the uncertainty itself for robust control. Terminal sliding mode control also yields improved convergence where convergence time is finite and is to be controlled. A further object is to apply terminal sliders to robot manipulator control and benchmark performance with the traditional computed torque control method and provide for design of control parameters.
Convergence of the frequency-size distribution of global earthquakes
Bell, Andrew F.; Naylor, Mark; Main, Ian G.
2013-06-01
The Gutenberg-Richter (GR) frequency-magnitude relation is a fundamental empirical law of seismology, but its form remains uncertain for rare extreme events. Here, we show that the temporal evolution of model likelihoods and parameters for the frequency-magnitude distribution of the global Harvard Centroid Moment Tensor catalog is inconsistent with an unbounded GR relation, despite if being the preferred model at the current time. During the recent spate of 12 great earthquakes in the last 8 years, record-breaking events result in profound steps in favor of the unbounded GR relation. However, between such events the preferred model gradually converges to the tapered GR relation, and the form of the convergence cannot be explained by random sampling of an unbounded GR distribution. The convergence properties are consistent with a global catalog composed of superposed randomly-sampled regional catalogs, each with different upper bounds, many of which have not yet sampled their largest event.
Convergent series for lattice models with polynomial interactions
Ivanov, Aleksandr S
2016-01-01
The standard perturbative weak-coupling expansions in lattice models are asymptotic. The reason for this is hidden in the incorrect interchange of the summation and integration. However, substituting the Gaussian initial approximation of the perturbative expansions by a certain interacting model or regularizing original lattice integrals, one can construct desired convergent series. In this paper we develop methods, which are based on the joint and separate utilization of the regularization and new initial approximation. We prove, that the convergent series exist and can be expressed as the re-summed standard perturbation theory for any model on the finite lattice with the polynomial interaction of even degree. We discuss properties of such series and make them applicable to practical computations. The workability of the methods is demonstrated on the example of the lattice $\\phi^4$-model. We calculate the operator $\\langle\\phi_n^2\\rangle$ using the convergent series, the comparison of the results with the Bo...
‘The Schneiderverse’: Nickelodeon, Convergent Television and Transmedia Storytelling
Helena Louise Dare-Edwards
2014-12-01
Full Text Available This article will analyse the textual features of two recent and successful Nickelodeon shows, both of which incorporate digital and social technologies into their sitcom-style format. Aimed at a tween-girl audience, these ‘convergence comedies’ complicate traditional notions of media spectatorship and the distinctions between media producers and consumers as audiences are invited to participate in the processes of production. While media convergence is built into the visual style of both shows, the shows themselves converge to create a shared fictional world, dubbed the ‘Schneiderverse’, which traverses the boundary between the real and the fictional. It will be considered how the audience’s media experience could be enriched through immersion in the online spaces associated with the texts.
Optimality Conditions and Finite Convergence of Lasserre's Hierarchy
Nie, Jiawang
2012-01-01
Lasserre's hierarchy is a sequence of semidefinite relaxations for solving polynomial optimization problems globally. This paper studies the relationship between optimality conditions in nonlinear programming theory and finite convergence of Lasserre's hierarchy. Our main results are: i) Lasserre's hierarchy has finite convergence when the constraint qualification, strict complementarity and second order sufficiency conditions hold at every global minimizer, under the standard archimedean assumption; ii) these optimality conditions are all satisfied at every local minimizer if a finite set of polynomials, which are in the coefficients of input polynomials, do not vanish at the input data (i.e., they hold in a Zariski open set). This implies that Lasserre's hierarchy has finite convergence generically.
The Learning Convergence of CMAC in Cyclic Learning
姚殊; 张钹
1994-01-01
In this paper we discuss the learning convergence of the cerebellar model articulation controller (CMAC) in cyclic learning.We prove the following results.First,if the training samples are noiseless,the training algorithm converges if and only if the learning rate is chosen from (0,2).Second,when the training samples have noises,the learning algorithm will converge with a probability of one if the learning rate is dynamically decreased.Third,in the case with noises,with a small but fixed learning rate ε the mean square error of the weight sequences generated by the CMAC learning algorithm will be bounded by O(ε).Some simulation experiments are carried out to test these results.
Converging spherical wave propagation in a hemispherical solid lens
Zhang, Yaoju; Ye, Xuehua; Chen, Junfeng
2006-06-01
The propagation of converging spherical waves through a hemispherical solid lens (HSL) is studied, and the multiple reflections inside the HSL are considered. It is found that the reflectivity and transmissivity have an oscillatory behaviour related to the optical radius of the HSL. When the refractive index of the HSL is smaller than that of the sample, the small mismatch in refractive indices is preferable for transmission-mode microscopy. But when the refractive index of the HSL is larger than that of the sample, the reflectivity increases rapidly as the mismatch in refractive indices and the converging angle of incident light increase, the larger mismatch and converging angle are useful for reflection-mode microscopy. The magnitude of the whole reflectivity and its modulation depth are strongly sensitive to the incident polarization, which is also discussed.
International Accounting Convergence in the Field of Fair Value Measurement
Diana Cozma Ighian
2015-09-01
Full Text Available The investors’ desire for high-quality, internationally comparable financial information that is useful for decision-making in increasingly global capital markets imposed an international convergence, the ultimate goal of which is a single set of international accounting standards that companies worldwide would use for both domestic and cross-border financial reporting. The guidance, set out in IFRS 13 Fair Value Measurement and the update to Topic 820 (formerly referred to as SFAS 157, completes a major project of the boards’ joint work to improve IFRSs and US GAAP and to bring about their convergence. This article describes the controversial history of fair value measurement and the main novelties in the field of fair value measurement, arising from the international convergence process.
Uniform convergence of Vapnik--Chervonenkis classes under ergodic sampling
Adams, Terrence M; 10.1214/09-AOP511
2010-01-01
We show that if $\\mathcal{X}$ is a complete separable metric space and $\\mathcal{C}$ is a countable family of Borel subsets of $\\mathcal{X}$ with finite VC dimension, then, for every stationary ergodic process with values in $\\mathcal{X}$, the relative frequencies of sets $C\\in\\mathcal{C}$ converge uniformly to their limiting probabilities. Beyond ergodicity, no assumptions are imposed on the sampling process, and no regularity conditions are imposed on the elements of $\\mathcal{C}$. The result extends existing work of Vapnik and Chervonenkis, among others, who have studied uniform convergence for i.i.d. and strongly mixing processes. Our method of proof is new and direct: it does not rely on symmetrization techniques, probability inequalities or mixing conditions. The uniform convergence of relative frequencies for VC-major and VC-graph classes of functions under ergodic sampling is established as a corollary of the basic result for sets.
Convergence of the discrete dipole approximation. I. Theoretical analysis
Yurkin, Maxim A; Hoekstra, Alfons G
2006-01-01
We performed a rigorous theoretical convergence analysis of the discrete dipole approximation (DDA). We prove that errors in any measured quantity are bounded by a sum of a linear and quadratic term in the size of a dipole d, when the latter is in the range of DDA applicability. Moreover, the linear term is significantly smaller for cubically than for non-cubically shaped scatterers. Therefore, for small d errors for cubically shaped particles are much smaller than for non-cubically shaped. The relative importance of the linear term decreases with increasing size, hence convergence of DDA for large enough scatterers is quadratic in the common range of d. Extensive numerical simulations were carried out for a wide range of d. Finally we discuss a number of new developments in DDA and their consequences for convergence.
Romania’s Accession to Second Modernity. Potential of Convergence
Marin Dinu
2006-04-01
Full Text Available This paper analyses Romanian economy facing with European integration process at 2007. The Romanian economy advanced the development prudent macroeconomics policies and implement structural reforms in the market for goods, labor and financial products. We identify in this study the principal conditionalities for the admittance in European Union. The nominal and real convergence must be touched faster because this process supposes stability prices, the financial soundness indicators, the need to stabilize exchange rate. In addition, the real convergence with European Union is very important. First, we analyze the strategic errors of the Romanian authorities in transition period. Second, our study focuses on current challenges and makes suggestions for change the modernization process. Can Romanian economy obtain a grow faster convergence? Is the strategy of Romanian economy optimal?
Modelling Iteration Convergence Condition for Single SAR Image Geocoding
Dong, Yuting; Liao, Minghsheng; Zhang, Lu; Shi, Xuguo
2014-11-01
Single SAR image geocoding is to determine the ground coordinate for each pixel in the SAR image assisted with an external DEM. Due to the uncertainty of the elevation of each pixel in SAR image, an iterative procedure is needed, which suffers from the problem of divergence in some difficult areas such as shaded and serious layover areas. This paper aims at theoretically analysing the convergence conditions that has not been intensively studied till now. To make the discussion easier, the Range-Doppler (RD) model is simplified and then the general surface is simplified into a planar surface. Mathematical deduction is carried out to derive the convergence conditions and the impact factors for the convergence speed are analysed. The theoretical findings are validated by experiments for both simulated and real surfaces.