WorldWideScience

Sample records for set partition sizes

  1. Seasonal and particle size-dependent variations in gas/particle partitioning of PCDD/Fs

    International Nuclear Information System (INIS)

    Lee, Se-Jin; Ale, Debaki; Chang, Yoon-Seok; Oh, Jeong-Eun; Shin, Sun Kyoung

    2008-01-01

    This study monitored particle size-dependent variations in atmospheric polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Two gas/particle partitioning models, the subcooled liquid vapor pressure (P L 0 ) and the octanol-air partition coefficient (K OA ) model, were applied to each particle sizes. The regression coefficients of each fraction against the gas/particle partition coefficient (K P ) were similar for separated particles within the same sample set but differed for particles collected during different periods. Gas/particle partitioning calculated from the integral of fractions was similar to that of size-segregated particles and previously measured bulk values. Despite the different behaviors and production mechanisms of atmospheric particles of different sizes, PCDD/F partitioning of each size range was controlled by meteorological conditions such as atmospheric temperature, O 3 and UV, which reflects no source related with certain particle size ranges but mixed urban sources within this city. Our observations emphasize that when assessing environmental and health effects, the movement of PCDD/Fs in air should be considered in conjunction with particle size in addition to the bulk aerosol. - Gas/particle partitioning of atmospheric PCDD/Fs for different particle sizes reflects the impacts of emitters of different size ranges

  2. The rank of the semigroup of transformations stabilising a partition of a finite set

    OpenAIRE

    Araujo, Joao; Bentz, Wolfram; Mitchell, J. D.; Schneider, Csaba

    2014-01-01

    Let $\\mathcal{P}$ be a partition of a finite set $X$. We say that a full transformation $f:X\\to X$ preserves (or stabilizes) the partition $\\mathcal{P}$ if for all $P\\in \\mathcal{P}$ there exists $Q\\in \\mathcal{P}$ such that $Pf\\subseteq Q$. Let $T(X,\\mathcal{P})$ denote the semigroup of all full transformations of $X$ that preserve the partition $\\mathcal{P}$. In 2005 Huisheng found an upper bound for the minimum size of the generating sets of $T(X,\\mathcal{P})$, when $\\mathcal{P}$ is a part...

  3. Partitioning the vertices of a graph into two total dominating sets ...

    African Journals Online (AJOL)

    A total dominating set in a graph G is a set S of vertices of G such that every vertex in G is adjacent to a vertex of S. We study graphs whose vertex set can be partitioned into two total dominating sets. In particular, we develop several sufficient conditions for a graph to have a vertex partition into two total dominating sets.

  4. Balanced partitions of 3-colored geometric sets in the plane

    NARCIS (Netherlands)

    Bereg, S.; Hurtado, F.; Kano, M.; Korman, M.; Lara, D.; Seara, C.; Silveira, R.I.; Urrutia, J.; Verbeek, K.A.B.

    2015-01-01

    Let SS be a finite set of geometric objects partitioned into classes or colors . A subset S'¿SS'¿S is said to be balanced if S'S' contains the same amount of elements of SS from each of the colors. We study several problems on partitioning 33-colored sets of points and lines in the plane into two

  5. Set Partitions and the Multiplication Principle

    Science.gov (United States)

    Lockwood, Elise; Caughman, John S., IV

    2016-01-01

    To further understand student thinking in the context of combinatorial enumeration, we examine student work on a problem involving set partitions. In this context, we note some key features of the multiplication principle that were often not attended to by students. We also share a productive way of thinking that emerged for several students who…

  6. Introducing Meta-Partition, a Useful Methodology to Explore Factors That Influence Ecological Effect Sizes.

    Directory of Open Access Journals (Sweden)

    Zaida Ortega

    Full Text Available The study of the heterogeneity of effect sizes is a key aspect of ecological meta-analyses. Here we propose a meta-analytic methodology to study the influence of moderators in effect sizes by splitting heterogeneity: meta-partition. To introduce this methodology, we performed a meta-partition of published data about the traits that influence species sensitivity to habitat loss, that have been previously analyzed through meta-regression. Thus, here we aim to introduce meta-partition and to make an initial comparison with meta-regression. Meta-partition algorithm consists of three steps. Step 1 is to study the heterogeneity of effect sizes under the assumption of fixed effect model. If heterogeneity is found, we perform step 2, that is, to partition the heterogeneity by the moderator that minimizes heterogeneity within a subset while maximizing heterogeneity between subsets. Then, if effect sizes of the subset are still heterogeneous, we repeat step 1 and 2 until we reach final subsets. Finally, step 3 is to integrate effect sizes of final subsets, with fixed effect model if there is homogeneity, and with random effects model if there is heterogeneity. Results show that meta-partition is valuable to assess the importance of moderators in explaining heterogeneity of effect sizes, as well as to assess the directions of these relations and to detect possible interactions between moderators. With meta-partition we have been able to evaluate the importance of moderators in a more objective way than with meta-regression, and to visualize the complex relations that may exist between them. As ecological issues are often influenced by several factors interacting in complex ways, ranking the importance of possible moderators and detecting possible interactions would make meta-partition a useful exploration tool for ecological meta-analyses.

  7. Fast parallel DNA-based algorithms for molecular computation: the set-partition problem.

    Science.gov (United States)

    Chang, Weng-Long

    2007-12-01

    This paper demonstrates that basic biological operations can be used to solve the set-partition problem. In order to achieve this, we propose three DNA-based algorithms, a signed parallel adder, a signed parallel subtractor and a signed parallel comparator, that formally verify our designed molecular solutions for solving the set-partition problem.

  8. Two castes sizes of leafcutter ants in task partitioning in foraging activity

    Directory of Open Access Journals (Sweden)

    Marcelo Arruda de Toledo

    Full Text Available ABSTRACT: Task partitioning in eusocial animals is most likely an evolutionary adaptation that optimizes the efficiency of the colony to grow and reproduce. It was investigated indirect task partitioning in two castes sizes; this involves task partitioning in which the material transported is not transferred directly from one individual to another, but where it is dropped by one ant to be picked up by another. In two separate approaches, it was confirmed previous results pertaining to leaf caching activities among Atta colombica with task partitioning activities involving leaf dropping among Atta sexdens rubropilosa , in which there is a correlation between the size of an individual ant and the leaf fragment it transports. It was also suggested that this correlation exists only in individual ants that cut and transport (CaT the same fragment to the nest. When task partitioning occurs and individual ants transporting (T leaf fragments cut by other ants, the correlation becomes looser or disappears. We also observed that CaT ants are smaller than T ants.

  9. Optimisation-Based Solution Methods for Set Partitioning Models

    DEFF Research Database (Denmark)

    Rasmussen, Matias Sevel

    The scheduling of crew, i.e. the construction of work schedules for crew members, is often not a trivial task, but a complex puzzle. The task is complicated by rules, restrictions, and preferences. Therefore, manual solutions as well as solutions from standard software packages are not always su......_cient with respect to solution quality and solution time. Enhancement of the overall solution quality as well as the solution time can be of vital importance to many organisations. The _elds of operations research and mathematical optimisation deal with mathematical modelling of di_cult scheduling problems (among...... other topics). The _elds also deal with the development of sophisticated solution methods for these mathematical models. This thesis describes the set partitioning model which has been widely used for modelling crew scheduling problems. Integer properties for the set partitioning model are shown...

  10. Size-exclusion partitioning of neutral solutes in crosslinked polymer networks: A Monte Carlo simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Quesada-Pérez, Manuel; Maroto-Centeno, José Alberto [Departamento de Física, Escuela Politécnica Superior de Linares, Universidad de Jaén, 23700 Linares, Jaén (Spain); Adroher-Benítez, Irene [Grupo de Física de Fluidos y Biocoloides, Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Granada, 18071 Granada (Spain)

    2014-05-28

    In this work, the size-exclusion partitioning of neutral solutes in crosslinked polymer networks has been studied through Monte Carlo simulations. Two models that provide user-friendly expressions to predict the partition coefficient have been tested over a wide range of volume fractions: Ogston's model (especially devised for fibrous media) and the pore model. The effects of crosslinking and bond stiffness have also been analyzed. Our results suggest that the fiber model can acceptably account for size-exclusion effects in crosslinked gels. Its predictions are good for large solutes if the fiber diameter is assumed to be the effective monomer diameter. For solutes sizes comparable to the monomer dimensions, a smaller fiber diameter must be used. Regarding the pore model, the partition coefficient is poorly predicted when the pore diameter is estimated as the distance between adjacent crosslinker molecules. On the other hand, our results prove that the pore sizes obtained from the pore model by fitting partitioning data of swollen gels are overestimated.

  11. Size-exclusion partitioning of neutral solutes in crosslinked polymer networks: A Monte Carlo simulation study

    International Nuclear Information System (INIS)

    Quesada-Pérez, Manuel; Maroto-Centeno, José Alberto; Adroher-Benítez, Irene

    2014-01-01

    In this work, the size-exclusion partitioning of neutral solutes in crosslinked polymer networks has been studied through Monte Carlo simulations. Two models that provide user-friendly expressions to predict the partition coefficient have been tested over a wide range of volume fractions: Ogston's model (especially devised for fibrous media) and the pore model. The effects of crosslinking and bond stiffness have also been analyzed. Our results suggest that the fiber model can acceptably account for size-exclusion effects in crosslinked gels. Its predictions are good for large solutes if the fiber diameter is assumed to be the effective monomer diameter. For solutes sizes comparable to the monomer dimensions, a smaller fiber diameter must be used. Regarding the pore model, the partition coefficient is poorly predicted when the pore diameter is estimated as the distance between adjacent crosslinker molecules. On the other hand, our results prove that the pore sizes obtained from the pore model by fitting partitioning data of swollen gels are overestimated

  12. Polycyclic aromatic hydrocarbons in urban atmosphere of Guangzhou, China: Size distribution characteristics and size-resolved gas-particle partitioning

    Science.gov (United States)

    Yu, Huan; Yu, Jian Zhen

    2012-07-01

    Size distributions of thirteen polycyclic aromatic hydrocarbons (PAHs), elemental carbon (EC), and organic carbon (OC) in the range of 0.01-18 μm were measured using a nano Micro-Orifice Uniform Deposit Impactor (nano-MOUDI) in an urban location in Guangzhou, China in July 2006. PAH size distributions were fit with five modes and the respective mass median aerodynamic diameters (MMAD) are: Aitken mode (MMAD: ˜0.05 μm), three accumulation modes AMI, AMII, AMIII (MMAD: 0.13-0.17 μm, 0.4-0.45 μm, and 0.9-1.2 μm, respectively), and coarse mode (MMAD: 4-6 μm). Seven-ring PAH was mainly in AMII and AMIII. Five- and six-ring PAHs were found to be abundant in all the three AM. Three- and four-ring PAHs had a significant presence in the coarse mode in addition to the three AM. Size-resolved gas-particle partition coefficients of PAHs (Kp) were estimated using measured EC and OC data. The Kp values of a given PAH could differ by a factor of up to ˜7 on particles in different size modes, with the highest Kp associated with the AMI particles and the lowest Kp associated with the coarse mode particles. Comparison of calculated overall Kp with measured Kp values in Guangzhou by Yang et al. (2010) shows that adsorption on EC appeared to be the dominant mechanism driving the gas-particle partitioning of three- and four-ring PAHs while absorption in OM played a dominant role for five- and six-ring PAHs. The calculated equilibrium timescales of repartitioning indicate that five- to seven-ring PAHs could not achieve equilibrium partitioning within their typical residence time in urban atmospheres, while three- and four-ring PAHs could readily reach new equilibrium states in particles of all sizes. A partitioning flux is therefore proposed to replace the equilibrium assumption in modeling PAH transport and fate.

  13. Equilibrium partitioning of macromolecules in confining geometries: Improved universality with a new molecular size parameter

    DEFF Research Database (Denmark)

    Wang, Yanwei; Peters, Günther H.J.; Hansen, Flemming Yssing

    2008-01-01

    structures (CABS), allows the computation of equilibrium partition coefficients as a function of confinement size solely based on a single sampling of the configuration space of a macromolecule in bulk. Superior in computational speed to previous computational methods, CABS is capable of handling slits...... parameter for characterization of spatial confinement effects on macromolecules. Results for the equilibrium partition coefficient in the weak confinement regime depend only on the ratio ofR-s to the confinement size regardless of molecular details....

  14. Autocatalytic sets in a partitioned biochemical network.

    Science.gov (United States)

    Smith, Joshua I; Steel, Mike; Hordijk, Wim

    2014-01-01

    In previous work, RAF theory has been developed as a tool for making theoretical progress on the origin of life question, providing insight into the structure and occurrence of self-sustaining and collectively autocatalytic sets within catalytic polymer networks. We present here an extension in which there are two "independent" polymer sets, where catalysis occurs within and between the sets, but there are no reactions combining polymers from both sets. Such an extension reflects the interaction between nucleic acids and peptides observed in modern cells and proposed forms of early life. We present theoretical work and simulations which suggest that the occurrence of autocatalytic sets is robust to the partitioned structure of the network. We also show that autocatalytic sets remain likely even when the molecules in the system are not polymers, and a low level of inhibition is present. Finally, we present a kinetic extension which assigns a rate to each reaction in the system, and show that identifying autocatalytic sets within such a system is an NP-complete problem. Recent experimental work has challenged the necessity of an RNA world by suggesting that peptide-nucleic acid interactions occurred early in chemical evolution. The present work indicates that such a peptide-RNA world could support the spontaneous development of autocatalytic sets and is thus a feasible alternative worthy of investigation.

  15. Integrated Berth Allocation and Quay Crane Assignment Problem: Set partitioning models and computational results

    DEFF Research Database (Denmark)

    Iris, Cagatay; Pacino, Dario; Røpke, Stefan

    2015-01-01

    Most of the operational problems in container terminals are strongly interconnected. In this paper, we study the integrated Berth Allocation and Quay Crane Assignment Problem in seaport container terminals. We will extend the current state-of-the-art by proposing novel set partitioning models....... To improve the performance of the set partitioning formulations, a number of variable reduction techniques are proposed. Furthermore, we analyze the effects of different discretization schemes and the impact of using a time-variant/invariant quay crane allocation policy. Computational experiments show...

  16. Probable relationship between partitions of the set of codons and the origin of the genetic code.

    Science.gov (United States)

    Salinas, Dino G; Gallardo, Mauricio O; Osorio, Manuel I

    2014-03-01

    Here we study the distribution of randomly generated partitions of the set of amino acid-coding codons. Some results are an application from a previous work, about the Stirling numbers of the second kind and triplet codes, both to the cases of triplet codes having four stop codons, as in mammalian mitochondrial genetic code, and hypothetical doublet codes. Extending previous results, in this work it is found that the most probable number of blocks of synonymous codons, in a genetic code, is similar to the number of amino acids when there are four stop codons, as well as it could be for a primigenious doublet code. Also it is studied the integer partitions associated to patterns of synonymous codons and it is shown, for the canonical code, that the standard deviation inside an integer partition is one of the most probable. We think that, in some early epoch, the genetic code might have had a maximum of the disorder or entropy, independent of the assignment between codons and amino acids, reaching a state similar to "code freeze" proposed by Francis Crick. In later stages, maybe deterministic rules have reassigned codons to amino acids, forming the natural codes, such as the canonical code, but keeping the numerical features describing the set partitions and the integer partitions, like a "fossil numbers"; both kinds of partitions about the set of amino acid-coding codons. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  17. Coding Partitions

    Directory of Open Access Journals (Sweden)

    Fabio Burderi

    2007-05-01

    Full Text Available Motivated by the study of decipherability conditions for codes weaker than Unique Decipherability (UD, we introduce the notion of coding partition. Such a notion generalizes that of UD code and, for codes that are not UD, allows to recover the ``unique decipherability" at the level of the classes of the partition. By tacking into account the natural order between the partitions, we define the characteristic partition of a code X as the finest coding partition of X. This leads to introduce the canonical decomposition of a code in at most one unambiguouscomponent and other (if any totally ambiguouscomponents. In the case the code is finite, we give an algorithm for computing its canonical partition. This, in particular, allows to decide whether a given partition of a finite code X is a coding partition. This last problem is then approached in the case the code is a rational set. We prove its decidability under the hypothesis that the partition contains a finite number of classes and each class is a rational set. Moreover we conjecture that the canonical partition satisfies such a hypothesis. Finally we consider also some relationships between coding partitions and varieties of codes.

  18. Lost in the supermarket: Quantifying the cost of partitioning memory sets in hybrid search.

    Science.gov (United States)

    Boettcher, Sage E P; Drew, Trafton; Wolfe, Jeremy M

    2018-01-01

    The items on a memorized grocery list are not relevant in every aisle; for example, it is useless to search for the cabbage in the cereal aisle. It might be beneficial if one could mentally partition the list so only the relevant subset was active, so that vegetables would be activated in the produce section. In four experiments, we explored observers' abilities to partition memory searches. For example, if observers held 16 items in memory, but only eight of the items were relevant, would response times resemble a search through eight or 16 items? In Experiments 1a and 1b, observers were not faster for the partition set; however, they suffered relatively small deficits when "lures" (items from the irrelevant subset) were presented, indicating that they were aware of the partition. In Experiment 2 the partitions were based on semantic distinctions, and again, observers were unable to restrict search to the relevant items. In Experiments 3a and 3b, observers attempted to remove items from the list one trial at a time but did not speed up over the course of a block, indicating that they also could not limit their memory searches. Finally, Experiments 4a, 4b, 4c, and 4d showed that observers were able to limit their memory searches when a subset was relevant for a run of trials. Overall, observers appear to be unable or unwilling to partition memory sets from trial to trial, yet they are capable of restricting search to a memory subset that remains relevant for several trials. This pattern is consistent with a cost to switching between currently relevant memory items.

  19. Allometry, sexual size dimorphism, and niche partitioning in the Mediterranean gecko (Hemidactylus turcicus)

    Science.gov (United States)

    James B. Johnson; Lance D. McBrayer; Daniel Saenz

    2005-01-01

    Hemidactylus tucrius is a small gekkonid lizard native to the Middle East and Asia that is known to exhibit sexual dimorphism in head size. Several potential explanations exist for the evolution and maintenance of sexual dimorphism in lizards. We tested 2 of these competing hypotheses concerning diet partitioning and differential growth. We found no...

  20. Wavelet compression of multichannel ECG data by enhanced set partitioning in hierarchical trees algorithm.

    Science.gov (United States)

    Sharifahmadian, Ershad

    2006-01-01

    The set partitioning in hierarchical trees (SPIHT) algorithm is very effective and computationally simple technique for image and signal compression. Here the author modified the algorithm which provides even better performance than the SPIHT algorithm. The enhanced set partitioning in hierarchical trees (ESPIHT) algorithm has performance faster than the SPIHT algorithm. In addition, the proposed algorithm reduces the number of bits in a bit stream which is stored or transmitted. I applied it to compression of multichannel ECG data. Also, I presented a specific procedure based on the modified algorithm for more efficient compression of multichannel ECG data. This method employed on selected records from the MIT-BIH arrhythmia database. According to experiments, the proposed method attained the significant results regarding compression of multichannel ECG data. Furthermore, in order to compress one signal which is stored for a long time, the proposed multichannel compression method can be utilized efficiently.

  1. Pesticides in the atmosphere: a comparison of gas-particle partitioning and particle size distribution of legacy and current-use pesticides

    Science.gov (United States)

    Degrendele, C.; Okonski, K.; Melymuk, L.; Landlová, L.; Kukučka, P.; Audy, O.; Kohoutek, J.; Čupr, P.; Klánová, J.

    2016-02-01

    This study presents a comparison of seasonal variation, gas-particle partitioning, and particle-phase size distribution of organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in air. Two years (2012/2013) of weekly air samples were collected at a background site in the Czech Republic using a high-volume air sampler. To study the particle-phase size distribution, air samples were also collected at an urban and rural site in the area of Brno, Czech Republic, using a cascade impactor separating atmospheric particulates according to six size fractions. Major differences were found in the atmospheric distribution of OCPs and CUPs. The atmospheric concentrations of CUPs were driven by agricultural activities while secondary sources such as volatilization from surfaces governed the atmospheric concentrations of OCPs. Moreover, clear differences were observed in gas-particle partitioning; CUP partitioning was influenced by adsorption onto mineral surfaces while OCPs were mainly partitioning to aerosols through absorption. A predictive method for estimating the gas-particle partitioning has been derived and is proposed for polar and non-polar pesticides. Finally, while OCPs and the majority of CUPs were largely found on fine particles, four CUPs (carbendazim, isoproturon, prochloraz, and terbuthylazine) had higher concentrations on coarse particles ( > 3.0 µm), which may be related to the pesticide application technique. This finding is particularly important and should be further investigated given that large particles result in lower risks from inhalation (regardless the toxicity of the pesticide) and lower potential for long-range atmospheric transport.

  2. Pesticides in the atmosphere: a comparison of gas-particle partitioning and particle size distribution of legacy and current-use pesticides

    Directory of Open Access Journals (Sweden)

    C. Degrendele

    2016-02-01

    Full Text Available This study presents a comparison of seasonal variation, gas-particle partitioning, and particle-phase size distribution of organochlorine pesticides (OCPs and current-use pesticides (CUPs in air. Two years (2012/2013 of weekly air samples were collected at a background site in the Czech Republic using a high-volume air sampler. To study the particle-phase size distribution, air samples were also collected at an urban and rural site in the area of Brno, Czech Republic, using a cascade impactor separating atmospheric particulates according to six size fractions. Major differences were found in the atmospheric distribution of OCPs and CUPs. The atmospheric concentrations of CUPs were driven by agricultural activities while secondary sources such as volatilization from surfaces governed the atmospheric concentrations of OCPs. Moreover, clear differences were observed in gas-particle partitioning; CUP partitioning was influenced by adsorption onto mineral surfaces while OCPs were mainly partitioning to aerosols through absorption. A predictive method for estimating the gas-particle partitioning has been derived and is proposed for polar and non-polar pesticides. Finally, while OCPs and the majority of CUPs were largely found on fine particles, four CUPs (carbendazim, isoproturon, prochloraz, and terbuthylazine had higher concentrations on coarse particles ( >  3.0 µm, which may be related to the pesticide application technique. This finding is particularly important and should be further investigated given that large particles result in lower risks from inhalation (regardless the toxicity of the pesticide and lower potential for long-range atmospheric transport.

  3. Searching for optimal integer solutions to set partitioning problems using column generation

    OpenAIRE

    Bredström, David; Jörnsten, Kurt; Rönnqvist, Mikael

    2007-01-01

    We describe a new approach to produce integer feasible columns to a set partitioning problem directly in solving the linear programming (LP) relaxation using column generation. Traditionally, column generation is aimed to solve the LP relaxation as quick as possible without any concern of the integer properties of the columns formed. In our approach we aim to generate the columns forming the optimal integer solution while simultaneously solving the LP relaxation. By this we can re...

  4. Partitioning an object-oriented terminology schema.

    Science.gov (United States)

    Gu, H; Perl, Y; Halper, M; Geller, J; Kuo, F; Cimino, J J

    2001-07-01

    Controlled medical terminologies are increasingly becoming strategic components of various healthcare enterprises. However, the typical medical terminology can be difficult to exploit due to its extensive size and high density. The schema of a medical terminology offered by an object-oriented representation is a valuable tool in providing an abstract view of the terminology, enhancing comprehensibility and making it more usable. However, schemas themselves can be large and unwieldy. We present a methodology for partitioning a medical terminology schema into manageably sized fragments that promote increased comprehension. Our methodology has a refinement process for the subclass hierarchy of the terminology schema. The methodology is carried out by a medical domain expert in conjunction with a computer. The expert is guided by a set of three modeling rules, which guarantee that the resulting partitioned schema consists of a forest of trees. This makes it easier to understand and consequently use the medical terminology. The application of our methodology to the schema of the Medical Entities Dictionary (MED) is presented.

  5. Classification algorithms using adaptive partitioning

    KAUST Repository

    Binev, Peter; Cohen, Albert; Dahmen, Wolfgang; DeVore, Ronald

    2014-01-01

    © 2014 Institute of Mathematical Statistics. Algorithms for binary classification based on adaptive tree partitioning are formulated and analyzed for both their risk performance and their friendliness to numerical implementation. The algorithms can be viewed as generating a set approximation to the Bayes set and thus fall into the general category of set estimators. In contrast with the most studied tree-based algorithms, which utilize piecewise constant approximation on the generated partition [IEEE Trans. Inform. Theory 52 (2006) 1335.1353; Mach. Learn. 66 (2007) 209.242], we consider decorated trees, which allow us to derive higher order methods. Convergence rates for these methods are derived in terms the parameter - of margin conditions and a rate s of best approximation of the Bayes set by decorated adaptive partitions. They can also be expressed in terms of the Besov smoothness β of the regression function that governs its approximability by piecewise polynomials on adaptive partition. The execution of the algorithms does not require knowledge of the smoothness or margin conditions. Besov smoothness conditions are weaker than the commonly used Holder conditions, which govern approximation by nonadaptive partitions, and therefore for a given regression function can result in a higher rate of convergence. This in turn mitigates the compatibility conflict between smoothness and margin parameters.

  6. Classification algorithms using adaptive partitioning

    KAUST Repository

    Binev, Peter

    2014-12-01

    © 2014 Institute of Mathematical Statistics. Algorithms for binary classification based on adaptive tree partitioning are formulated and analyzed for both their risk performance and their friendliness to numerical implementation. The algorithms can be viewed as generating a set approximation to the Bayes set and thus fall into the general category of set estimators. In contrast with the most studied tree-based algorithms, which utilize piecewise constant approximation on the generated partition [IEEE Trans. Inform. Theory 52 (2006) 1335.1353; Mach. Learn. 66 (2007) 209.242], we consider decorated trees, which allow us to derive higher order methods. Convergence rates for these methods are derived in terms the parameter - of margin conditions and a rate s of best approximation of the Bayes set by decorated adaptive partitions. They can also be expressed in terms of the Besov smoothness β of the regression function that governs its approximability by piecewise polynomials on adaptive partition. The execution of the algorithms does not require knowledge of the smoothness or margin conditions. Besov smoothness conditions are weaker than the commonly used Holder conditions, which govern approximation by nonadaptive partitions, and therefore for a given regression function can result in a higher rate of convergence. This in turn mitigates the compatibility conflict between smoothness and margin parameters.

  7. Nudging physician prescription decisions by partitioning the order set: results of a vignette-based study.

    Science.gov (United States)

    Tannenbaum, David; Doctor, Jason N; Persell, Stephen D; Friedberg, Mark W; Meeker, Daniella; Friesema, Elisha M; Goldstein, Noah J; Linder, Jeffrey A; Fox, Craig R

    2015-03-01

    Healthcare professionals are rapidly adopting electronic health records (EHRs). Within EHRs, seemingly innocuous menu design configurations can influence provider decisions for better or worse. The purpose of this study was to examine whether the grouping of menu items systematically affects prescribing practices among primary care providers. We surveyed 166 primary care providers in a research network of practices in the greater Chicago area, of whom 84 responded (51% response rate). Respondents and non-respondents were similar on all observable dimensions except that respondents were more likely to work in an academic setting. The questionnaire consisted of seven clinical vignettes. Each vignette described typical signs and symptoms for acute respiratory infections, and providers chose treatments from a menu of options. For each vignette, providers were randomly assigned to one of two menu partitions. For antibiotic-inappropriate vignettes, the treatment menu either listed over-the-counter (OTC) medications individually while grouping prescriptions together, or displayed the reverse partition. For antibiotic-appropriate vignettes, the treatment menu either listed narrow-spectrum antibiotics individually while grouping broad-spectrum antibiotics, or displayed the reverse partition. The main outcome was provider treatment choice. For antibiotic-inappropriate vignettes, we categorized responses as prescription drugs or OTC-only options. For antibiotic-appropriate vignettes, we categorized responses as broad- or narrow-spectrum antibiotics. Across vignettes, there was an 11.5 percentage point reduction in choosing aggressive treatment options (e.g., broad-spectrum antibiotics) when aggressive options were grouped compared to when those same options were listed individually (95% CI: 2.9 to 20.1%; p = .008). Provider treatment choice appears to be influenced by the grouping of menu options, suggesting that the layout of EHR order sets is not an arbitrary exercise

  8. Heurísticas, planos secantes y optimización subgradiente para set partitioning

    OpenAIRE

    Barceló, Jaume; Fernández, E.

    1988-01-01

    En este artículo se estudian los problemas de Set Partitioning (SP) desde una perspectiva algorítmica. El diseño de un procedimiento heurístico permite no sólo disponer de soluciones posibles para los mismos, sino también obtener desigualdades válidas que sean violadas por las soluciones posibles a partir de las que se obtienen. La incorporación a los problemas originales de las desigualdades válidas obtenidas proporcionan unos problemas ampliados (SPA) para los que también se propone un proc...

  9. The partition dimension of cycle books graph

    Science.gov (United States)

    Santoso, Jaya; Darmaji

    2018-03-01

    Let G be a nontrivial and connected graph with vertex set V(G), edge set E(G) and S ⊆ V(G) with v ∈ V(G), the distance between v and S is d(v,S) = min{d(v,x)|x ∈ S}. For an ordered partition ∏ = {S 1, S 2, S 3,…, Sk } of V(G), the representation of v with respect to ∏ is defined by r(v|∏) = (d(v, S 1), d(v, S 2),…, d(v, Sk )). The partition ∏ is called a resolving partition of G if all representations of vertices are distinct. The partition dimension pd(G) is the smallest integer k such that G has a resolving partition set with k members. In this research, we will determine the partition dimension of Cycle Books {B}{Cr,m}. Cycle books graph {B}{Cr,m} is a graph consisting of m copies cycle Cr with the common path P 2. It is shown that the partition dimension of cycle books graph, pd({B}{C3,m}) is 3 for m = 2, 3, and m for m ≥ 4. pd({B}{C4,m}) is 3 + 2k for m = 3k + 2, 4 + 2(k ‑ 1) for m = 3k + 1, and 3 + 2(k ‑ 1) for m = 3k. pd({B}{C5,m}) is m + 1.

  10. Plasma membrane partitioning: from macro-domains to new views on plasmodesmata

    Directory of Open Access Journals (Sweden)

    Yohann eBoutté

    2014-04-01

    Full Text Available Compartmentalization of cellular functions relies on partitioning of domains of diverse sizes within the plasma membrane (PM. Macro-domains measure several micrometers and contain specific proteins concentrated to specific sides (apical, basal and lateral of the PM conferring a polarity to the cell. Cell polarity is one of the driving forces in tissue and growth patterning. To maintain macro-domains within the PM, eukaryotic cells exert diverse mechanisms to counteract the free lateral diffusion of proteins. Protein activation/inactivation, endocytosis, PM recycling of transmembrane proteins and the role of diffusion barriers in macro-domains partitioning at PM will be discussed. Moreover, as plasmodesmata (PDs are domains inserted within the PM which also mediate tissue and growth patterning, it is essential to understand how segregation of specific set of proteins is maintained at PDs while PDs domains are smaller in size compared to macro-domains. Here, we will present mechanisms allowing restriction of proteins at PM macrodomains, but for which molecular components have been found in PDs proteome. We will explore the hypothesis that partitioning of macro-domains and PDs may be ruled by similar mechanisms.

  11. Adaptively loaded IM/DD optical OFDM based on set-partitioned QAM formats.

    Science.gov (United States)

    Zhao, Jian; Chen, Lian-Kuan

    2017-04-17

    We investigate the constellation design and symbol error rate (SER) of set-partitioned (SP) quadrature amplitude modulation (QAM) formats. Based on the SER analysis, we derive the adaptive bit and power loading algorithm for SP QAM based intensity-modulation direct-detection (IM/DD) orthogonal frequency division multiplexing (OFDM). We experimentally show that the proposed system significantly outperforms the conventional adaptively-loaded IM/DD OFDM and can increase the data rate from 36 Gbit/s to 42 Gbit/s in the presence of severe dispersion-induced spectral nulls after 40-km single-mode fiber. It is also shown that the adaptive algorithm greatly enhances the tolerance to fiber nonlinearity and allows for more power budget.

  12. New Linear Partitioning Models Based on Experimental Water: Supercritical CO2 Partitioning Data of Selected Organic Compounds.

    Science.gov (United States)

    Burant, Aniela; Thompson, Christopher; Lowry, Gregory V; Karamalidis, Athanasios K

    2016-05-17

    Partitioning coefficients of organic compounds between water and supercritical CO2 (sc-CO2) are necessary to assess the risk of migration of these chemicals from subsurface CO2 storage sites. Despite the large number of potential organic contaminants, the current data set of published water-sc-CO2 partitioning coefficients is very limited. Here, the partitioning coefficients of thiophene, pyrrole, and anisole were measured in situ over a range of temperatures and pressures using a novel pressurized batch-reactor system with dual spectroscopic detectors: a near-infrared spectrometer for measuring the organic analyte in the CO2 phase and a UV detector for quantifying the analyte in the aqueous phase. Our measured partitioning coefficients followed expected trends based on volatility and aqueous solubility. The partitioning coefficients and literature data were then used to update a published poly parameter linear free-energy relationship and to develop five new linear free-energy relationships for predicting water-sc-CO2 partitioning coefficients. A total of four of the models targeted a single class of organic compounds. Unlike models that utilize Abraham solvation parameters, the new relationships use vapor pressure and aqueous solubility of the organic compound at 25 °C and CO2 density to predict partitioning coefficients over a range of temperature and pressure conditions. The compound class models provide better estimates of partitioning behavior for compounds in that class than does the model built for the entire data set.

  13. An Association-Oriented Partitioning Approach for Streaming Graph Query

    Directory of Open Access Journals (Sweden)

    Yun Hao

    2017-01-01

    Full Text Available The volumes of real-world graphs like knowledge graph are increasing rapidly, which makes streaming graph processing a hot research area. Processing graphs in streaming setting poses significant challenges from different perspectives, among which graph partitioning method plays a key role. Regarding graph query, a well-designed partitioning method is essential for achieving better performance. Existing offline graph partitioning methods often require full knowledge of the graph, which is not possible during streaming graph processing. In order to handle this problem, we propose an association-oriented streaming graph partitioning method named Assc. This approach first computes the rank values of vertices with a hybrid approximate PageRank algorithm. After splitting these vertices with an adapted variant affinity propagation algorithm, the process order on vertices in the sliding window can be determined. Finally, according to the level of these vertices and their association, the partition where the vertices should be distributed is decided. We compare its performance with a set of streaming graph partition methods and METIS, a widely adopted offline approach. The results show that our solution can partition graphs with hundreds of millions of vertices in streaming setting on a large collection of graph datasets and our approach outperforms other graph partitioning methods.

  14. The Train Driver Recovery Problem - a Set Partitioning Based Model and Solution Method

    DEFF Research Database (Denmark)

    Rezanova, Natalia Jurjevna; Ryan, David

    2010-01-01

    The need to recover a train driver schedule occurs during major disruptions in the daily railway operations. Based on data from the Danish passenger railway operator DSB S-tog A/S, a solution method to the train driver recovery problem (TDRP) is developed. The TDRP is formulated as a set...... branching strategy using the depth-first search of the Branch & Bound tree. The LP relaxation of the TDRP possesses strong integer properties. We present test scenarios generated from the historical real-life operations data of DSB S-tog A/S. The numerical results show that all but one tested instances...... partitioning problem. We define a disruption neighbourhood by identifying a small set of drivers and train tasks directly affected by the disruption. Based on the disruption neighbourhood, the TDRP model is formed and solved. If the TDRP solution provides a feasible recovery for the drivers within...

  15. Shell use and partitioning of two sympatric species of hermit crabs on a tropical mudflat

    Science.gov (United States)

    Teoh, Hong Wooi; Chong, Ving Ching

    2014-02-01

    Shell use and partitioning of two sympatric hermit crab species (Diogenes moosai and Diogenes lopochir), as determined by shell shape, size and availability, were examined from August 2009 to March 2011 in a tropical mudflat (Malaysia). Shells of 14 gastropod species were used but > 85% comprised shells of Cerithidea cingulata, Nassarius cf. olivaceus, Nassarius jacksonianus, and Thais malayensis. Shell partitioning between hermit crab species, sexes, and developmental stages was evident from occupied shells of different species, shapes, and sizes. Extreme bias in shell use pattern by male and female of both species of hermit crabs suggests that shell shape, which depends on shell species, is the major determinant of shell use. The hermit crab must however fit well into the shell so that compatibility between crab size and shell size becomes crucial. Although shell availability possibly influenced shell use and hermit crab distribution, this is not critical in a tropical setting of high gastropod diversity and abundance.

  16. Lift of dilogarithm to partition identities

    International Nuclear Information System (INIS)

    Terhoeven, M.

    1992-11-01

    For the whole set of dilogarithm identities found recently using the thermodynamic Bethe-Ansatz for the ADET series of purely elastic scattering theories we give partition identities which involve characters of those conformal field theories which correspond to the UV-limits of the scattering theories. These partition identities in turn allow to derive the dilogarithm identities using modular invariance and a saddle point approximation. We conjecture on possible generalizations of this correspondance, namely, a lift from dilogarithm to partition identities. (orig.)

  17. The prediction of blood-tissue partitions, water-skin partitions and skin permeation for agrochemicals.

    Science.gov (United States)

    Abraham, Michael H; Gola, Joelle M R; Ibrahim, Adam; Acree, William E; Liu, Xiangli

    2014-07-01

    There is considerable interest in the blood-tissue distribution of agrochemicals, and a number of researchers have developed experimental methods for in vitro distribution. These methods involve the determination of saline-blood and saline-tissue partitions; not only are they indirect, but they do not yield the required in vivo distribution. The authors set out equations for gas-tissue and blood-tissue distribution, for partition from water into skin and for permeation from water through human skin. Together with Abraham descriptors for the agrochemicals, these equations can be used to predict values for all of these processes. The present predictions compare favourably with experimental in vivo blood-tissue distribution where available. The predictions require no more than simple arithmetic. The present method represents a much easier and much more economic way of estimating blood-tissue partitions than the method that uses saline-blood and saline-tissue partitions. It has the added advantages of yielding the required in vivo partitions and being easily extended to the prediction of partition of agrochemicals from water into skin and permeation from water through skin. © 2013 Society of Chemical Industry.

  18. Limit Shapes and Fluctuations of Bounded Random Partitions

    DEFF Research Database (Denmark)

    Beltoft, Dan

    Random partitions of integers, bounded both in the number of summands and the size of each summand are considered, subject to the probability measure which assigns a probability proportional to some fixed positive number to the power of the number being partitioned. This corresponds to considering...

  19. The Benefits of Adaptive Partitioning for Parallel AMR Applications

    Energy Technology Data Exchange (ETDEWEB)

    Steensland, Johan [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Advanced Software Research and Development

    2008-07-01

    Parallel adaptive mesh refinement methods potentially lead to realistic modeling of complex three-dimensional physical phenomena. However, the dynamics inherent in these methods present significant challenges in data partitioning and load balancing. Significant human resources, including time, effort, experience, and knowledge, are required for determining the optimal partitioning technique for each new simulation. In reality, scientists resort to using the on-board partitioner of the computational framework, or to using the partitioning industry standard, ParMetis. Adaptive partitioning refers to repeatedly selecting, configuring and invoking the optimal partitioning technique at run-time, based on the current state of the computer and application. In theory, adaptive partitioning automatically delivers superior performance and eliminates the need for repeatedly spending valuable human resources for determining the optimal static partitioning technique. In practice, however, enabling frameworks are non-existent due to the inherent significant inter-disciplinary research challenges. This paper presents a study of a simple implementation of adaptive partitioning and discusses implied potential benefits from the perspective of common groups of users within computational science. The study is based on a large set of data derived from experiments including six real-life, multi-time-step adaptive applications from various scientific domains, five complementing and fundamentally different partitioning techniques, a large set of parameters corresponding to a wide spectrum of computing environments, and a flexible cost function that considers the relative impact of multiple partitioning metrics and diverse partitioning objectives. The results show that even a simple implementation of adaptive partitioning can automatically generate results statistically equivalent to the best static partitioning. Thus, it is possible to effectively eliminate the problem of determining the

  20. Study of energy partitioning using a set of related explosive formulations

    Science.gov (United States)

    Lieber, Mark; Foster, Joseph C.; Stewart, D. Scott

    2012-03-01

    Condensed phase high explosives convert potential energy stored in the electro-magnetic field structure of complex molecules to high power output during the detonation process. Historically, the explosive design problem has focused on intramolecular energy storage. The molecules of interest are derived via molecular synthesis providing near stoichiometric balance on the physical scale of the molecule. This approach provides prompt reactions based on transport physics at the molecular scale. Modern material design has evolved to approaches that employ intermolecular ingredients to alter the spatial and temporal distribution of energy release. State of the art continuum methods have been used to study this approach to the materials design. Cheetah has been used to produce data for a set of fictitious explosive formulations based on C-4 to study the partitioning of the available energy between internal and kinetic energy in the detonation. The equation of state information from Cheetah has been used in ALE3D to develop an understanding of the relationship between variations in the formulation parameters and the internal energy cycle in the products.

  1. Inside-sediment partitioning of PAH, PCB and organochlorine compounds and inferences on sampling and normalization methods

    International Nuclear Information System (INIS)

    Opel, Oliver; Palm, Wolf-Ulrich; Steffen, Dieter; Ruck, Wolfgang K.L.

    2011-01-01

    Comparability of sediment analyses for semivolatile organic substances is still low. Neither screening of the sediments nor organic-carbon based normalization is sufficient to obtain comparable results. We are showing the interdependency of grain-size effects with inside-sediment organic-matter distribution for PAH, PCB and organochlorine compounds. Surface sediment samples collected by Van-Veen grab were sieved and analyzed for 16 PAH, 6 PCB and 18 organochlorine pesticides (OCP) as well as organic-matter content. Since bulk concentrations are influenced by grain-size effects themselves, we used a novel normalization method based on the sum of concentrations in the separate grain-size fractions of the sediments. By calculating relative normalized concentrations, it was possible to clearly show underlying mechanisms throughout a heterogeneous set of samples. Furthermore, we were able to show that, for comparability, screening at <125 μm is best suited and can be further improved by additional organic-carbon normalization. - Research highlights: → New method for the comparison of heterogeneous sets of sediment samples. → Assessment of organic pollutants partitioning mechanisms in sediments. → Proposed method for more comparable sediment sampling. - Inside-sediment partitioning mechanisms are shown using a new mathematical approach and discussed in terms of sediment sampling and normalization.

  2. PERFORMANCE ANALYSIS OF SET PARTITIONING IN HIERARCHICAL TREES (SPIHT ALGORITHM FOR A FAMILY OF WAVELETS USED IN COLOR IMAGE COMPRESSION

    Directory of Open Access Journals (Sweden)

    A. Sreenivasa Murthy

    2014-11-01

    Full Text Available With the spurt in the amount of data (Image, video, audio, speech, & text available on the net, there is a huge demand for memory & bandwidth savings. One has to achieve this, by maintaining the quality & fidelity of the data acceptable to the end user. Wavelet transform is an important and practical tool for data compression. Set partitioning in hierarchal trees (SPIHT is a widely used compression algorithm for wavelet transformed images. Among all wavelet transform and zero-tree quantization based image compression algorithms SPIHT has become the benchmark state-of-the-art algorithm because it is simple to implement & yields good results. In this paper we present a comparative study of various wavelet families for image compression with SPIHT algorithm. We have conducted experiments with Daubechies, Coiflet, Symlet, Bi-orthogonal, Reverse Bi-orthogonal and Demeyer wavelet types. The resulting image quality is measured objectively, using peak signal-to-noise ratio (PSNR, and subjectively, using perceived image quality (human visual perception, HVP for short. The resulting reduction in the image size is quantified by compression ratio (CR.

  3. PAQ: Partition Analysis of Quasispecies.

    Science.gov (United States)

    Baccam, P; Thompson, R J; Fedrigo, O; Carpenter, S; Cornette, J L

    2001-01-01

    The complexities of genetic data may not be accurately described by any single analytical tool. Phylogenetic analysis is often used to study the genetic relationship among different sequences. Evolutionary models and assumptions are invoked to reconstruct trees that describe the phylogenetic relationship among sequences. Genetic databases are rapidly accumulating large amounts of sequences. Newly acquired sequences, which have not yet been characterized, may require preliminary genetic exploration in order to build models describing the evolutionary relationship among sequences. There are clustering techniques that rely less on models of evolution, and thus may provide nice exploratory tools for identifying genetic similarities. Some of the more commonly used clustering methods perform better when data can be grouped into mutually exclusive groups. Genetic data from viral quasispecies, which consist of closely related variants that differ by small changes, however, may best be partitioned by overlapping groups. We have developed an intuitive exploratory program, Partition Analysis of Quasispecies (PAQ), which utilizes a non-hierarchical technique to partition sequences that are genetically similar. PAQ was used to analyze a data set of human immunodeficiency virus type 1 (HIV-1) envelope sequences isolated from different regions of the brain and another data set consisting of the equine infectious anemia virus (EIAV) regulatory gene rev. Analysis of the HIV-1 data set by PAQ was consistent with phylogenetic analysis of the same data, and the EIAV rev variants were partitioned into two overlapping groups. PAQ provides an additional tool which can be used to glean information from genetic data and can be used in conjunction with other tools to study genetic similarities and genetic evolution of viral quasispecies.

  4. Random skew plane partitions with a piecewise periodic back wall

    DEFF Research Database (Denmark)

    Boutillier, Cedric; Mkrtchyan, Sevak; Reshetikhin, Nicolai

    Random skew plane partitions of large size distributed according to an appropriately scaled Schur process develop limit shapes. In the present work we consider the limit of large random skew plane partitions where the inner boundary approaches a piecewise linear curve with non-lattice slopes. Muc...

  5. Sharing-Aware Horizontal Partitioning for Exploiting Correlations during Query Processing

    DEFF Research Database (Denmark)

    Tzoumas, Kostas; Deshpande, Amol; Jensen, Christian Søndergaard

    2010-01-01

    Optimization of join queries based on average selectivities is suboptimal in highly correlated databases. In such databases, relations are naturally divided into partitions, each partition having substantially different statistical characteristics. It is very compelling to discover such data...... partitions during query optimization and create multiple plans for a given query, one plan being optimal for a particular combination of data partitions. This scenario calls for the sharing of state among plans, so that common intermediate results are not recomputed. We study this problem in a setting...

  6. Sea urchins in a high-CO2 world: partitioned effects of body size, ocean warming and acidification on metabolic rate.

    Science.gov (United States)

    Carey, Nicholas; Harianto, Januar; Byrne, Maria

    2016-04-15

    Body size and temperature are the major factors explaining metabolic rate, and the additional factor of pH is a major driver at the biochemical level. These three factors have frequently been found to interact, complicating the formulation of broad models predicting metabolic rates and hence ecological functioning. In this first study of the effects of warming and ocean acidification, and their potential interaction, on metabolic rate across a broad range in body size (two to three orders of magnitude difference in body mass), we addressed the impact of climate change on the sea urchin ITALIC! Heliocidaris erythrogrammain context with climate projections for southeast Australia, an ocean warming hotspot. Urchins were gradually introduced to two temperatures (18 and 23°C) and two pH levels (7.5 and 8.0), at which they were maintained for 2 months. Identical experimental trials separated by several weeks validated the fact that a new physiological steady state had been reached, otherwise known as acclimation. The relationship between body size, temperature and acidification on the metabolic rate of ITALIC! H. erythrogrammawas strikingly stable. Both stressors caused increases in metabolic rate: 20% for temperature and 19% for pH. Combined effects were additive: a 44% increase in metabolism. Body size had a highly stable relationship with metabolic rate regardless of temperature or pH. None of these diverse drivers of metabolism interacted or modulated the effects of the others, highlighting the partitioned nature of how each influences metabolic rate, and the importance of achieving a full acclimation state. Despite these increases in energetic demand there was very limited capacity for compensatory modulating of feeding rate; food consumption increased only in the very smallest specimens, and only in response to temperature, and not pH. Our data show that warming, acidification and body size all substantially affect metabolism and are highly consistent and

  7. The position value for partition function form network games

    NARCIS (Netherlands)

    Nouweland, van den C.G.A.M.; Slikker, M.

    We use the axiomatization of the position value for network situations in van den Nouweland and Slikker (2012) to define a position value for partition function form network situations. We do this by generalizing the axioms to the partition function form value function setting as studied in Navarro

  8. Intersexual Trophic Niche Partitioning in an Ant-Eating spider (Araneae: Zodariidae)

    DEFF Research Database (Denmark)

    Pekár, Stanislav; Martisová, Martina; Bilde, T.

    2011-01-01

    lead to higher energy demands in females driven by fecundity selection, while males invest in mate searching. We tested predictions of the two hypotheses underlying intersexual trophic niche partitioning in a natural population of spiders. Zodarion jozefienae spiders specialize on Messor barbarus ants...... that are polymorphic in body size and hence comprise potential trophic niches for the spider, making this system well-suited to study intersexual trophic niche partitioning. Methodology/Principal Findings Comparative analysis of trophic morphology (the chelicerae) and body size of males, females and juveniles...... demonstrated highly female biased SSD (Sexual Size Dimorphism) in body size, body weight, and in the size of chelicerae, the latter arising from sex-specific growth patterns in trophic morphology. In the field, female spiders actively selected ant sub-castes that were larger than the average prey size...

  9. Hypergraph partitioning implementation for parallelizing matrix-vector multiplication using CUDA GPU-based parallel computing

    Science.gov (United States)

    Murni, Bustamam, A.; Ernastuti, Handhika, T.; Kerami, D.

    2017-07-01

    Calculation of the matrix-vector multiplication in the real-world problems often involves large matrix with arbitrary size. Therefore, parallelization is needed to speed up the calculation process that usually takes a long time. Graph partitioning techniques that have been discussed in the previous studies cannot be used to complete the parallelized calculation of matrix-vector multiplication with arbitrary size. This is due to the assumption of graph partitioning techniques that can only solve the square and symmetric matrix. Hypergraph partitioning techniques will overcome the shortcomings of the graph partitioning technique. This paper addresses the efficient parallelization of matrix-vector multiplication through hypergraph partitioning techniques using CUDA GPU-based parallel computing. CUDA (compute unified device architecture) is a parallel computing platform and programming model that was created by NVIDIA and implemented by the GPU (graphics processing unit).

  10. BKP plane partitions

    International Nuclear Information System (INIS)

    Foda, Omar; Wheeler, Michael

    2007-01-01

    Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another

  11. BKP plane partitions

    Energy Technology Data Exchange (ETDEWEB)

    Foda, Omar; Wheeler, Michael [Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria 3010 (Australia)

    2007-01-15

    Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another.

  12. Set size and culture influence children's attention to number.

    Science.gov (United States)

    Cantrell, Lisa; Kuwabara, Megumi; Smith, Linda B

    2015-03-01

    Much research evidences a system in adults and young children for approximately representing quantity. Here we provide evidence that the bias to attend to discrete quantity versus other dimensions may be mediated by set size and culture. Preschool-age English-speaking children in the United States and Japanese-speaking children in Japan were tested in a match-to-sample task where number was pitted against cumulative surface area in both large and small numerical set comparisons. Results showed that children from both cultures were biased to attend to the number of items for small sets. Large set responses also showed a general attention to number when ratio difficulty was easy. However, relative to the responses for small sets, attention to number decreased for both groups; moreover, both U.S. and Japanese children showed a significant bias to attend to total amount for difficult numerical ratio distances, although Japanese children shifted attention to total area at relatively smaller set sizes than U.S. children. These results add to our growing understanding of how quantity is represented and how such representation is influenced by context--both cultural and perceptual. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Partitional clustering algorithms

    CERN Document Server

    2015-01-01

    This book summarizes the state-of-the-art in partitional clustering. Clustering, the unsupervised classification of patterns into groups, is one of the most important tasks in exploratory data analysis. Primary goals of clustering include gaining insight into, classifying, and compressing data. Clustering has a long and rich history that spans a variety of scientific disciplines including anthropology, biology, medicine, psychology, statistics, mathematics, engineering, and computer science. As a result, numerous clustering algorithms have been proposed since the early 1950s. Among these algorithms, partitional (nonhierarchical) ones have found many applications, especially in engineering and computer science. This book provides coverage of consensus clustering, constrained clustering, large scale and/or high dimensional clustering, cluster validity, cluster visualization, and applications of clustering. Examines clustering as it applies to large and/or high-dimensional data sets commonly encountered in reali...

  14. A novel partitioning method for block-structured adaptive meshes

    Science.gov (United States)

    Fu, Lin; Litvinov, Sergej; Hu, Xiangyu Y.; Adams, Nikolaus A.

    2017-07-01

    We propose a novel partitioning method for block-structured adaptive meshes utilizing the meshless Lagrangian particle concept. With the observation that an optimum partitioning has high analogy to the relaxation of a multi-phase fluid to steady state, physically motivated model equations are developed to characterize the background mesh topology and are solved by multi-phase smoothed-particle hydrodynamics. In contrast to well established partitioning approaches, all optimization objectives are implicitly incorporated and achieved during the particle relaxation to stationary state. Distinct partitioning sub-domains are represented by colored particles and separated by a sharp interface with a surface tension model. In order to obtain the particle relaxation, special viscous and skin friction models, coupled with a tailored time integration algorithm are proposed. Numerical experiments show that the present method has several important properties: generation of approximately equal-sized partitions without dependence on the mesh-element type, optimized interface communication between distinct partitioning sub-domains, continuous domain decomposition which is physically localized and implicitly incremental. Therefore it is particularly suitable for load-balancing of high-performance CFD simulations.

  15. A novel partitioning method for block-structured adaptive meshes

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Lin, E-mail: lin.fu@tum.de; Litvinov, Sergej, E-mail: sergej.litvinov@aer.mw.tum.de; Hu, Xiangyu Y., E-mail: xiangyu.hu@tum.de; Adams, Nikolaus A., E-mail: nikolaus.adams@tum.de

    2017-07-15

    We propose a novel partitioning method for block-structured adaptive meshes utilizing the meshless Lagrangian particle concept. With the observation that an optimum partitioning has high analogy to the relaxation of a multi-phase fluid to steady state, physically motivated model equations are developed to characterize the background mesh topology and are solved by multi-phase smoothed-particle hydrodynamics. In contrast to well established partitioning approaches, all optimization objectives are implicitly incorporated and achieved during the particle relaxation to stationary state. Distinct partitioning sub-domains are represented by colored particles and separated by a sharp interface with a surface tension model. In order to obtain the particle relaxation, special viscous and skin friction models, coupled with a tailored time integration algorithm are proposed. Numerical experiments show that the present method has several important properties: generation of approximately equal-sized partitions without dependence on the mesh-element type, optimized interface communication between distinct partitioning sub-domains, continuous domain decomposition which is physically localized and implicitly incremental. Therefore it is particularly suitable for load-balancing of high-performance CFD simulations.

  16. Exact Cover Problem in Milton Babbitt's All-partition Array

    OpenAIRE

    Bemman, Brian; Meredith, David

    2015-01-01

    One aspect of analyzing Milton Babbitt’s (1916–2011) all- partition arrays requires finding a sequence of distinct, non-overlapping aggregate regions that completely and exactly covers an irregular matrix of pitch class integers. This is an example of the so-called exact cover problem. Given a set, A, and a collection of distinct subsets of this set, S, then a subset of S is an exact cover of A if it exhaustively and exclu- sively partitions A. We provide a backtracking algorithm for solving ...

  17. Partition wall structure in spent fuel storage pool and construction method for the partition wall

    International Nuclear Information System (INIS)

    Izawa, Masaaki

    1998-01-01

    A partitioning wall for forming cask pits as radiation shielding regions by partitioning inside of a spent fuel storage pool is prepared by covering both surface of a concrete body by shielding metal plates. The metal plate comprises opposed plate units integrated by welding while sandwiching a metal frame as a reinforcing material for the concrete body, the lower end of the units is connected to a floor of a pool by fastening members, and concrete is set while using the metal plate of the units as a frame to form the concrete body. The shielding metal plate has a double walled structure formed by welding a lining plate disposed on the outer surface of the partition wall and a shield plate disposed to the inner side. Then the term for construction can be shortened, and the capacity for storing spent fuels can be increased. (N.H.)

  18. Intersexual trophic niche partitioning in an ant-eating spider (Araneae: Zodariidae.

    Directory of Open Access Journals (Sweden)

    Stano Pekár

    2011-01-01

    Full Text Available Divergence in trophic niche between the sexes may function to reduce competition between the sexes ("intersexual niche partitioning hypothesis", or may be result from differential selection among the sexes on maximizing reproductive output ("sexual selection hypothesis". The latter may lead to higher energy demands in females driven by fecundity selection, while males invest in mate searching. We tested predictions of the two hypotheses underlying intersexual trophic niche partitioning in a natural population of spiders. Zodarion jozefienae spiders specialize on Messor barbarus ants that are polymorphic in body size and hence comprise potential trophic niches for the spider, making this system well-suited to study intersexual trophic niche partitioning.Comparative analysis of trophic morphology (the chelicerae and body size of males, females and juveniles demonstrated highly female biased SSD (Sexual Size Dimorphism in body size, body weight, and in the size of chelicerae, the latter arising from sex-specific growth patterns in trophic morphology. In the field, female spiders actively selected ant sub-castes that were larger than the average prey size, and larger than ants captured by juveniles and males. Female fecundity was highly positively correlated with female body mass, which reflects foraging success during the adult stage. Females in laboratory experiments preferred the large ant sub-castes and displayed higher capture efficiency. In contrast, males occupied a different trophic niche and showed reduced foraging effort and reduced prey capture and feeding efficiency compared with females and juveniles.Our data indicate that female-biased dimorphism in trophic morphology and body size correlate with sex-specific reproductive strategies. We propose that intersexual trophic niche partitioning is shaped primarily by fecundity selection in females, and results from sex-differences in the route to successful reproduction where females are

  19. Consistent Estimation of Partition Markov Models

    Directory of Open Access Journals (Sweden)

    Jesús E. García

    2017-04-01

    Full Text Available The Partition Markov Model characterizes the process by a partition L of the state space, where the elements in each part of L share the same transition probability to an arbitrary element in the alphabet. This model aims to answer the following questions: what is the minimal number of parameters needed to specify a Markov chain and how to estimate these parameters. In order to answer these questions, we build a consistent strategy for model selection which consist of: giving a size n realization of the process, finding a model within the Partition Markov class, with a minimal number of parts to represent the process law. From the strategy, we derive a measure that establishes a metric in the state space. In addition, we show that if the law of the process is Markovian, then, eventually, when n goes to infinity, L will be retrieved. We show an application to model internet navigation patterns.

  20. Hashing for Statistics over K-Partitions

    DEFF Research Database (Denmark)

    Dahlgaard, Soren; Knudsen, Mathias Baek Tejs; Rotenberg, Eva

    2015-01-01

    In this paper we analyze a hash function for k-partitioning a set into bins, obtaining strong concentration bounds for standard algorithms combining statistics from each bin. This generic method was originally introduced by Flajolet and Martin [FOCS'83] in order to save a factor Ω(k) of time per...... concentration bounds on the most popular applications of k-partitioning similar to those we would get using a truly random hash function. The analysis is very involved and implies several new results of independent interest for both simple and double tabulation, e.g. A simple and efficient construction...

  1. Unique Path Partitions

    DEFF Research Database (Denmark)

    Bessenrodt, Christine; Olsson, Jørn Børling; Sellers, James A.

    2013-01-01

    We give a complete classification of the unique path partitions and study congruence properties of the function which enumerates such partitions.......We give a complete classification of the unique path partitions and study congruence properties of the function which enumerates such partitions....

  2. Utility Independent Privacy Preserving Data Mining - Horizontally Partitioned Data

    Directory of Open Access Journals (Sweden)

    E Poovammal

    2010-06-01

    Full Text Available Micro data is a valuable source of information for research. However, publishing data about individuals for research purposes, without revealing sensitive information, is an important problem. The main objective of privacy preserving data mining algorithms is to obtain accurate results/rules by analyzing the maximum possible amount of data without unintended information disclosure. Data sets for analysis may be in a centralized server or in a distributed environment. In a distributed environment, the data may be horizontally or vertically partitioned. We have developed a simple technique by which horizontally partitioned data can be used for any type of mining task without information loss. The partitioned sensitive data at 'm' different sites are transformed using a mapping table or graded grouping technique, depending on the data type. This transformed data set is given to a third party for analysis. This may not be a trusted party, but it is still allowed to perform mining operations on the data set and to release the results to all the 'm' parties. The results are interpreted among the 'm' parties involved in the data sharing. The experiments conducted on real data sets prove that our proposed simple transformation procedure preserves one hundred percent of the performance of any data mining algorithm as compared to the original data set while preserving privacy.

  3. Analyzing ROC curves using the effective set-size model

    Science.gov (United States)

    Samuelson, Frank W.; Abbey, Craig K.; He, Xin

    2018-03-01

    The Effective Set-Size model has been used to describe uncertainty in various signal detection experiments. The model regards images as if they were an effective number (M*) of searchable locations, where the observer treats each location as a location-known-exactly detection task with signals having average detectability d'. The model assumes a rational observer behaves as if he searches an effective number of independent locations and follows signal detection theory at each location. Thus the location-known-exactly detectability (d') and the effective number of independent locations M* fully characterize search performance. In this model the image rating in a single-response task is assumed to be the maximum response that the observer would assign to these many locations. The model has been used by a number of other researchers, and is well corroborated. We examine this model as a way of differentiating imaging tasks that radiologists perform. Tasks involving more searching or location uncertainty may have higher estimated M* values. In this work we applied the Effective Set-Size model to a number of medical imaging data sets. The data sets include radiologists reading screening and diagnostic mammography with and without computer-aided diagnosis (CAD), and breast tomosynthesis. We developed an algorithm to fit the model parameters using two-sample maximum-likelihood ordinal regression, similar to the classic bi-normal model. The resulting model ROC curves are rational and fit the observed data well. We find that the distributions of M* and d' differ significantly among these data sets, and differ between pairs of imaging systems within studies. For example, on average tomosynthesis increased readers' d' values, while CAD reduced the M* parameters. We demonstrate that the model parameters M* and d' are correlated. We conclude that the Effective Set-Size model may be a useful way of differentiating location uncertainty from the diagnostic uncertainty in medical

  4. The heavy metal partition in size-fractions of the fine particles in agricultural soils contaminated by waste water and smelter dust

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Haibo, E-mail: hbzhang@yic.ac.cn [Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China); Luo, Yongming, E-mail: ymluo@yic.ac.cn [Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China); Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Makino, Tomoyuki [National Institute for Agro-Environmental Sciences, Tsukuba 3058604 (Japan); Wu, Longhua [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Nanzyo, Masami [Tohoku University, Sendai 9808576 (Japan)

    2013-03-15

    Highlights: ► A continuous flow ultra-centrifugation method has been developed to obtain fine particles from polluted agricultural soil. ► Pollution source affected the heavy metal fractionation in size-fractions by changing soil particle properties. ► The iron oxides affected the distribution of lead species more than other metals in the smelter dust polluted particles. -- Abstract: The partitioning of pollutant in the size-fractions of fine particles is particularly important to its migration and bioavailability in soil environment. However, the impact of pollution sources on the partitioning was seldom addressed in the previous studies. In this study, the method of continuous flow ultra-centrifugation was developed to separate three size fractions (<1 μm, <0.6 μm and <0.2 μm) of the submicron particles from the soil polluted by wastewater and smelter dust respectively. The mineralogy and physicochemical properties of each size-fraction were characterized by X-ray diffraction, transmission electron microscope etc. Total content of the polluted metals and their chemical speciation were measured. A higher enrichment factor of the metals in the fractions of <1 μm or less were observed in the soil contaminated by wastewater than by smelter dust. The organic substance in the wastewater and calcite from lime application were assumed to play an important role in the metal accumulation in the fine particles of the wastewater polluted soil. While the metal accumulation in the fine particles of the smelter dust polluted soil is mainly associated with Mn oxides. Cadmium speciation in both soils is dominated by dilute acid soluble form and lead speciation in the smelter dust polluted soil is dominated by reducible form in all particles. This implied that the polluted soils might be a high risk to human health and ecosystem due to the high bioaccessblity of the metals as well as the mobility of the fine particles in soil.

  5. The heavy metal partition in size-fractions of the fine particles in agricultural soils contaminated by waste water and smelter dust

    International Nuclear Information System (INIS)

    Zhang, Haibo; Luo, Yongming; Makino, Tomoyuki; Wu, Longhua; Nanzyo, Masami

    2013-01-01

    Highlights: ► A continuous flow ultra-centrifugation method has been developed to obtain fine particles from polluted agricultural soil. ► Pollution source affected the heavy metal fractionation in size-fractions by changing soil particle properties. ► The iron oxides affected the distribution of lead species more than other metals in the smelter dust polluted particles. -- Abstract: The partitioning of pollutant in the size-fractions of fine particles is particularly important to its migration and bioavailability in soil environment. However, the impact of pollution sources on the partitioning was seldom addressed in the previous studies. In this study, the method of continuous flow ultra-centrifugation was developed to separate three size fractions (<1 μm, <0.6 μm and <0.2 μm) of the submicron particles from the soil polluted by wastewater and smelter dust respectively. The mineralogy and physicochemical properties of each size-fraction were characterized by X-ray diffraction, transmission electron microscope etc. Total content of the polluted metals and their chemical speciation were measured. A higher enrichment factor of the metals in the fractions of <1 μm or less were observed in the soil contaminated by wastewater than by smelter dust. The organic substance in the wastewater and calcite from lime application were assumed to play an important role in the metal accumulation in the fine particles of the wastewater polluted soil. While the metal accumulation in the fine particles of the smelter dust polluted soil is mainly associated with Mn oxides. Cadmium speciation in both soils is dominated by dilute acid soluble form and lead speciation in the smelter dust polluted soil is dominated by reducible form in all particles. This implied that the polluted soils might be a high risk to human health and ecosystem due to the high bioaccessblity of the metals as well as the mobility of the fine particles in soil

  6. Effects of Group Size on Students Mathematics Achievement in Small Group Settings

    Science.gov (United States)

    Enu, Justice; Danso, Paul Amoah; Awortwe, Peter K.

    2015-01-01

    An ideal group size is hard to obtain in small group settings; hence there are groups with more members than others. The purpose of the study was to find out whether group size has any effects on students' mathematics achievement in small group settings. Two third year classes of the 2011/2012 academic year were selected from two schools in the…

  7. Nitrogen deficiency in maize. I. Effects on crop growth, development, dry matter partitioning, and kernel set

    International Nuclear Information System (INIS)

    Uhart, S.A.; Andrade, F.H.

    1995-01-01

    Variations in N availability affect growth and development of maize (Zea mays L.) and may lead to changes in crop physiological conditions at flowering and in kernel set. The objectives of this study were (i) to establish the effect of N availability on crop development, crop radiation interception, radiation use efficiency, and dry matter partitioning; and (ii) to study the relationship between kernel number and crop growth at flowering and between kernel number and crop N accumulation at flowering. Three experiments with a commercial hybrid (DK636) were carried out under field conditions at the INTA Balcarce Experimental Station, Argentina, without water limitations. The treatments consisted of different radiation levels, obtained by shading, combined with different levels of N availability obtained by the addition of N fertilizer or organic matter to immobilize N. Nitrogen deficiencies delayed both vegetative and reproductive phenological development, slightly reduced leaf emergence rate, and strongly diminished leaf expansion rate and leaf area duration. Nitrogen deficiencies reduced radiation interception as much as radiation use efficiency and their effects on the ear dry mater/total dry matter ratio at harvest were associated with crop growth rate reductions at flowering. Dry matter partitioning to reproductive sinks at flowering and the ear dry matter/total dry matter ratio at harvest were reduced by N shortages. Significant relationships between kernel number and N accumulation rate or crop growth rate at flowering were fitted by linear + plateau functions with thresholds above which kernel number and grain yield did not increase

  8. Information overload or search-amplified risk? Set size and order effects on decisions from experience.

    Science.gov (United States)

    Hills, Thomas T; Noguchi, Takao; Gibbert, Michael

    2013-10-01

    How do changes in choice-set size influence information search and subsequent decisions? Moreover, does information overload influence information processing with larger choice sets? We investigated these questions by letting people freely explore sets of gambles before choosing one of them, with the choice sets either increasing or decreasing in number for each participant (from two to 32 gambles). Set size influenced information search, with participants taking more samples overall, but sampling a smaller proportion of gambles and taking fewer samples per gamble, when set sizes were larger. The order of choice sets also influenced search, with participants sampling from more gambles and taking more samples overall if they started with smaller as opposed to larger choice sets. Inconsistent with information overload, information processing appeared consistent across set sizes and choice order conditions, reliably favoring gambles with higher sample means. Despite the lack of evidence for information overload, changes in information search did lead to systematic changes in choice: People who started with smaller choice sets were more likely to choose gambles with the highest expected values, but only for small set sizes. For large set sizes, the increase in total samples increased the likelihood of encountering rare events at the same time that the reduction in samples per gamble amplified the effect of these rare events when they occurred-what we call search-amplified risk. This led to riskier choices for individuals whose choices most closely followed the sample mean.

  9. Selective partitioning of cholesterol and a model drug into liposomes of varying size

    DEFF Research Database (Denmark)

    Decker, Christiane; Fahr, Alfred; Kuntsche, Judith

    2012-01-01

    The resistance of a lipid bilayer with respect to a bending deformation generally depends on the presence of membrane additives such as sterols, cosurfactants, peptides, and drugs. As a consequence, the partitioning of membrane additives into liposomes becomes selective with respect to liposome s...

  10. Partitioning of the variance in the growth parameters of Erwinia carotovora on vegetable products.

    Science.gov (United States)

    Shorten, P R; Membré, J-M; Pleasants, A B; Kubaczka, M; Soboleva, T K

    2004-06-01

    The objective of this paper was to estimate and partition the variability in the microbial growth model parameters describing the growth of Erwinia carotovora on pasteurised and non-pasteurised vegetable juice from laboratory experiments performed under different temperature-varying conditions. We partitioned the model parameter variance and covariance components into effects due to temperature profile and replicate using a maximum likelihood technique. Temperature profile and replicate were treated as random effects and the food substrate was treated as a fixed effect. The replicate variance component was small indicating a high level of control in this experiment. Our analysis of the combined E. carotovora growth data sets used the Baranyi primary microbial growth model along with the Ratkowsky secondary growth model. The variability in the microbial growth parameters estimated from these microbial growth experiments is essential for predicting the mean and variance through time of the E. carotovora population size in a product supply chain and is the basis for microbiological risk assessment and food product shelf-life estimation. The variance partitioning made here also assists in the management of optimal product distribution networks by identifying elements of the supply chain contributing most to product variability. Copyright 2003 Elsevier B.V.

  11. Phylogenetic systematics and biogeography of hummingbirds: Bayesian and maximum likelihood analyses of partitioned data and selection of an appropriate partitioning strategy.

    Science.gov (United States)

    McGuire, Jimmy A; Witt, Christopher C; Altshuler, Douglas L; Remsen, J V

    2007-10-01

    Hummingbirds are an important model system in avian biology, but to date the group has been the subject of remarkably few phylogenetic investigations. Here we present partitioned Bayesian and maximum likelihood phylogenetic analyses for 151 of approximately 330 species of hummingbirds and 12 outgroup taxa based on two protein-coding mitochondrial genes (ND2 and ND4), flanking tRNAs, and two nuclear introns (AK1 and BFib). We analyzed these data under several partitioning strategies ranging between unpartitioned and a maximum of nine partitions. In order to select a statistically justified partitioning strategy following partitioned Bayesian analysis, we considered four alternative criteria including Bayes factors, modified versions of the Akaike information criterion for small sample sizes (AIC(c)), Bayesian information criterion (BIC), and a decision-theoretic methodology (DT). Following partitioned maximum likelihood analyses, we selected a best-fitting strategy using hierarchical likelihood ratio tests (hLRTS), the conventional AICc, BIC, and DT, concluding that the most stringent criterion, the performance-based DT, was the most appropriate methodology for selecting amongst partitioning strategies. In the context of our well-resolved and well-supported phylogenetic estimate, we consider the historical biogeography of hummingbirds using ancestral state reconstructions of (1) primary geographic region of occurrence (i.e., South America, Central America, North America, Greater Antilles, Lesser Antilles), (2) Andean or non-Andean geographic distribution, and (3) minimum elevational occurrence. These analyses indicate that the basal hummingbird assemblages originated in the lowlands of South America, that most of the principle clades of hummingbirds (all but Mountain Gems and possibly Bees) originated on this continent, and that there have been many (at least 30) independent invasions of other primary landmasses, especially Central America.

  12. Generalised twisted partition functions

    CERN Document Server

    Petkova, V B

    2001-01-01

    We consider the set of partition functions that result from the insertion of twist operators compatible with conformal invariance in a given 2D Conformal Field Theory (CFT). A consistency equation, which gives a classification of twists, is written and solved in particular cases. This generalises old results on twisted torus boundary conditions, gives a physical interpretation of Ocneanu's algebraic construction, and might offer a new route to the study of properties of CFT.

  13. Inference of boundaries in causal sets

    Science.gov (United States)

    Cunningham, William J.

    2018-05-01

    We investigate the extrinsic geometry of causal sets in (1+1) -dimensional Minkowski spacetime. The properties of boundaries in an embedding space can be used not only to measure observables, but also to supplement the discrete action in the partition function via discretized Gibbons–Hawking–York boundary terms. We define several ways to represent a causal set using overlapping subsets, which then allows us to distinguish between null and non-null bounding hypersurfaces in an embedding space. We discuss algorithms to differentiate between different types of regions, consider when these distinctions are possible, and then apply the algorithms to several spacetime regions. Numerical results indicate the volumes of timelike boundaries can be measured to within 0.5% accuracy for flat boundaries and within 10% accuracy for highly curved boundaries for medium-sized causal sets with N  =  214 spacetime elements.

  14. Estimation of octanol/water partition coefficients using LSER parameters

    Science.gov (United States)

    Luehrs, Dean C.; Hickey, James P.; Godbole, Kalpana A.; Rogers, Tony N.

    1998-01-01

    The logarithms of octanol/water partition coefficients, logKow, were regressed against the linear solvation energy relationship (LSER) parameters for a training set of 981 diverse organic chemicals. The standard deviation for logKow was 0.49. The regression equation was then used to estimate logKow for a test of 146 chemicals which included pesticides and other diverse polyfunctional compounds. Thus the octanol/water partition coefficient may be estimated by LSER parameters without elaborate software but only moderate accuracy should be expected.

  15. Schmidt games and Markov partitions

    International Nuclear Information System (INIS)

    Tseng, Jimmy

    2009-01-01

    Let T be a C 2 -expanding self-map of a compact, connected, C ∞ , Riemannian manifold M. We correct a minor gap in the proof of a theorem from the literature: the set of points whose forward orbits are nondense has full Hausdorff dimension. Our correction allows us to strengthen the theorem. Combining the correction with Schmidt games, we generalize the theorem in dimension one: given a point x 0 in M, the set of points whose forward orbit closures miss x 0 is a winning set. Finally, our key lemma, the no matching lemma, may be of independent interest in the theory of symbolic dynamics or the theory of Markov partitions

  16. Summer–winter concentrations and gas-particle partitioning of short chain chlorinated paraffins in the atmosphere of an urban setting

    International Nuclear Information System (INIS)

    Wang Thanh; Han Shanlong; Yuan Bo; Zeng Lixi; Li Yingming; Wang Yawei; Jiang Guibin

    2012-01-01

    Short chain chlorinated paraffins (SCCPs) are semi-volatile chemicals that are considered persistent in the environment, potential toxic and subject to long-range transport. This study investigates the concentrations and gas-particle partitioning of SCCPs at an urban site in Beijing during summer and wintertime. The total atmospheric SCCP levels ranged 1.9–33.0 ng/m 3 during wintertime. Significantly higher levels were found during the summer (range 112–332 ng/m 3 ). The average fraction of total SCCPs in the particle phase (φ) was 0.67 during wintertime but decreased significantly during the summer (φ = 0.06). The ten and eleven carbon chain homologues with five to eight chlorine atoms were the predominant SCCP formula groups in air. Significant linear correlations were found between the gas-particle partition coefficients and the predicted subcooled vapor pressures and octanol–air partition coefficients. The gas-particle partitioning of SCCPs was further investigated and compared with both the Junge–Pankow adsorption and K oa -based absorption models. - Highlights: ► Short chain chlorinated paraffins were investigated in air samples from Beijing. ► Higher levels of SCCPs were found in air during summertime than wintertime. ► Relevant physical–chemical properties were estimated by SPARC and EPI Suite. ► Obtained data were used to model the gas-particle partitioning of SCCPs. - Atmospheric levels and gas-particle partitioning of SCCPs in Beijing, China.

  17. Nested partitions method, theory and applications

    CERN Document Server

    Shi, Leyuan

    2009-01-01

    There is increasing need to solve large-scale complex optimization problems in a wide variety of science and engineering applications, including designing telecommunication networks for multimedia transmission, planning and scheduling problems in manufacturing and military operations, or designing nanoscale devices and systems. Advances in technology and information systems have made such optimization problems more and more complicated in terms of size and uncertainty. Nested Partitions Method, Theory and Applications provides a cutting-edge research tool to use for large-scale, complex systems optimization. The Nested Partitions (NP) framework is an innovative mix of traditional optimization methodology and probabilistic assumptions. An important feature of the NP framework is that it combines many well-known optimization techniques, including dynamic programming, mixed integer programming, genetic algorithms and tabu search, while also integrating many problem-specific local search heuristics. The book uses...

  18. A Timing-Driven Partitioning System for Multiple FPGAs

    Directory of Open Access Journals (Sweden)

    Kalapi Roy

    1996-01-01

    Full Text Available Field-programmable systems with multiple FPGAs on a PCB or an MCM are being used by system designers when a single FPGA is not sufficient. We address the problem of partitioning a large technology mapped FPGA circuit onto multiple FPGA devices of a specific target technology. The physical characteristics of the multiple FPGA system (MFS pose additional constraints to the circuit partitioning algorithms: the capacity of each FPGA, the timing constraints, the number of I/Os per FPGA, and the pre-designed interconnection patterns of each FPGA and the package. Existing partitioning techniques which minimize just the cut sizes of partitions fail to satisfy the above challenges. We therefore present a timing driven N-way partitioning algorithm based on simulated annealing for technology-mapped FPGA circuits. The signal path delays are estimated during partitioning using a timing model specific to a multiple FPGA architecture. The model combines all possible delay factors in a system with multiple FPGA chips of a target technology. Furthermore, we have incorporated a new dynamic net-weighting scheme to minimize the number of pin-outs for each chip. Finally, we have developed a graph-based global router for pin assignment which can handle the pre-routed connections of our MFS structure. In order to reduce the time spent in the simulated annealing phase of the partitioner, clusters of circuit components are identified by a new linear-time bottom-up clustering algorithm. The annealing-based N-way partitioner executes four times faster using the clusters as opposed to a flat netlist with improved partitioning results. For several industrial circuits, our approach outperforms the recursive min-cut bi-partitioning algorithm by 35% in terms of nets cut. Our approach also outperforms an industrial FPGA partitioner by 73% on average in terms of unroutable nets. Using the performance optimization capabilities in our approach we have successfully partitioned the

  19. Matrix-vector multiplication using digital partitioning for more accurate optical computing

    Science.gov (United States)

    Gary, C. K.

    1992-01-01

    Digital partitioning offers a flexible means of increasing the accuracy of an optical matrix-vector processor. This algorithm can be implemented with the same architecture required for a purely analog processor, which gives optical matrix-vector processors the ability to perform high-accuracy calculations at speeds comparable with or greater than electronic computers as well as the ability to perform analog operations at a much greater speed. Digital partitioning is compared with digital multiplication by analog convolution, residue number systems, and redundant number representation in terms of the size and the speed required for an equivalent throughput as well as in terms of the hardware requirements. Digital partitioning and digital multiplication by analog convolution are found to be the most efficient alogrithms if coding time and hardware are considered, and the architecture for digital partitioning permits the use of analog computations to provide the greatest throughput for a single processor.

  20. Zeta Function Expression of Spin Partition Functions on Thermal AdS3

    Directory of Open Access Journals (Sweden)

    Floyd L.Williams

    2015-07-01

    Full Text Available We find a Selberg zeta function expression of certain one-loop spin partition functions on three-dimensional thermal anti-de Sitter space. Of particular interest is the partition function of higher spin fermionic particles. We also set up, in the presence of spin, a Patterson-type formula involving the logarithmic derivative of zeta.

  1. Differential Evolution and Particle Swarm Optimization for Partitional Clustering

    DEFF Research Database (Denmark)

    Krink, Thiemo; Paterlini, Sandra

    2006-01-01

    for numerical optimisation, which are hardly known outside the search heuristics field, are particle swarm optimisation (PSO) and differential evolution (DE). The performance of GAs for a representative point evolution approach to clustering is compared with PSO and DE. The empirical results show that DE......Many partitional clustering algorithms based on genetic algorithms (GA) have been proposed to tackle the problem of finding the optimal partition of a data set. Very few studies considered alternative stochastic search heuristics other than GAs or simulated annealing. Two promising algorithms...

  2. A Discrete Dynamical Model of Signed Partitions

    Directory of Open Access Journals (Sweden)

    G. Chiaselotti

    2013-01-01

    Full Text Available We use a discrete dynamical model with three evolution rules in order to analyze the structure of a partially ordered set of signed integer partitions whose main properties are actually not known. This model is related to the study of some extremal combinatorial sum problems.

  3. Partitioning of Nanoparticles into Organic Phases and Model Cells

    Energy Technology Data Exchange (ETDEWEB)

    Posner, J.D.; Westerhoff, P.; Hou, W-C.

    2011-08-25

    There is a recognized need to understand and predict the fate, transport and bioavailability of engineered nanoparticles (ENPs) in aquatic and soil ecosystems. Recent research focuses on either collection of empirical data (e.g., removal of a specific NP through water or soil matrices under variable experimental conditions) or precise NP characterization (e.g. size, degree of aggregation, morphology, zeta potential, purity, surface chemistry, and stability). However, it is almost impossible to transition from these precise measurements to models suitable to assess the NP behavior in the environment with complex and heterogeneous matrices. For decades, the USEPA has developed and applies basic partitioning parameters (e.g., octanol-water partition coefficients) and models (e.g., EPI Suite, ECOSAR) to predict the environmental fate, bioavailability, and toxicity of organic pollutants (e.g., pesticides, hydrocarbons, etc.). In this project we have investigated the hypothesis that NP partition coefficients between water and organic phases (octanol or lipid bilayer) is highly dependent on their physiochemical properties, aggregation, and presence of natural constituents in aquatic environments (salts, natural organic matter), which may impact their partitioning into biological matrices (bioaccumulation) and human exposure (bioavailability) as well as the eventual usage in modeling the fate and bioavailability of ENPs. In this report, we use the terminology "partitioning" to operationally define the fraction of ENPs distributed among different phases. The mechanisms leading to this partitioning probably involve both chemical force interactions (hydrophobic association, hydrogen bonding, ligand exchange, etc.) and physical forces that bring the ENPs in close contact with the phase interfaces (diffusion, electrostatic interactions, mixing turbulence, etc.). Our work focuses on partitioning, but also provides insight into the relative behavior of ENPs as either "more like

  4. Photosynthate partitioning in alfalfa before harvest and during regrowth

    International Nuclear Information System (INIS)

    Cralle, H.T.; Heichel, G.H.

    1988-01-01

    During the harvest regrowth cycle of alfalfa (Medicago sativa L.) plants, factors such as source to sink distance, sink size, and inter-organ competition continually change. However, consequent changes in the pattern of photosynthate partitioning from leaves to other organs are poorly understood. The authors objective was to examine photosynthate partitioning from upper and lower alfalfa leaves at intervals before herbage harvest and during regrowth after harvest. The uppermost or lowest fully expanded leaf on the longest or dominant stem was labeled with 14 CO 2 . After a 24-h translocation period, the plants were divided into various organs to determine distribution of the radiocarbon. At that time, the upper leaf preferentially partitioned photosynthate to the shoot apex, unexpanded leaves and auxillary shoots of the dominant shoot, whereas the lower leaf preferentially distributed photosynthate to the crown shoots, crown, root, and nodules. Expressions of 14 C partitioning were affected differently by organ mass. While the smallest organs such as nodules and unexpanded leaves always ranked higher for 14 C based on relative specific activity, the largest organs such as roots and crown shoots accumulated the largest percentage of total plant recovered radioactivity. The results illustrate the importance of growth stage and leaf position in photosynthate partitioning in alfalfa and the dominance of herbage meristems for current photosynthate during regrowth

  5. Improving small RNA-seq by using a synthetic spike-in set for size-range quality control together with a set for data normalization.

    Science.gov (United States)

    Locati, Mauro D; Terpstra, Inez; de Leeuw, Wim C; Kuzak, Mateusz; Rauwerda, Han; Ensink, Wim A; van Leeuwen, Selina; Nehrdich, Ulrike; Spaink, Herman P; Jonker, Martijs J; Breit, Timo M; Dekker, Rob J

    2015-08-18

    There is an increasing interest in complementing RNA-seq experiments with small-RNA (sRNA) expression data to obtain a comprehensive view of a transcriptome. Currently, two main experimental challenges concerning sRNA-seq exist: how to check the size distribution of isolated sRNAs, given the sensitive size-selection steps in the protocol; and how to normalize data between samples, given the low complexity of sRNA types. We here present two separate sets of synthetic RNA spike-ins for monitoring size-selection and for performing data normalization in sRNA-seq. The size-range quality control (SRQC) spike-in set, consisting of 11 oligoribonucleotides (10-70 nucleotides), was tested by intentionally altering the size-selection protocol and verified via several comparative experiments. We demonstrate that the SRQC set is useful to reproducibly track down biases in the size-selection in sRNA-seq. The external reference for data-normalization (ERDN) spike-in set, consisting of 19 oligoribonucleotides, was developed for sample-to-sample normalization in differential-expression analysis of sRNA-seq data. Testing and applying the ERDN set showed that it can reproducibly detect differential expression over a dynamic range of 2(18). Hence, biological variation in sRNA composition and content between samples is preserved while technical variation is effectively minimized. Together, both spike-in sets can significantly improve the technical reproducibility of sRNA-seq. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. LRSim: A Linked-Reads Simulator Generating Insights for Better Genome Partitioning

    Directory of Open Access Journals (Sweden)

    Ruibang Luo

    Full Text Available Linked-read sequencing, using highly-multiplexed genome partitioning and barcoding, can span hundreds of kilobases to improve de novo assembly, haplotype phasing, and other applications. Based on our analysis of 14 datasets, we introduce LRSim that simulates linked-reads by emulating the library preparation and sequencing process with fine control over variants, linked-read characteristics, and the short-read profile. We conclude from the phasing and assembly of multiple datasets, recommendations on coverage, fragment length, and partitioning when sequencing genomes of different sizes and complexities. These optimizations improve results by orders of magnitude, and enable the development of novel methods. LRSim is available at https://github.com/aquaskyline/LRSIM. Keywords: Linked-read, Molecular barcoding, Reads partitioning, Phasing, Reads simulation, Genome assembly, 10X Genomics

  7. Canonical partition functions: ideal quantum gases, interacting classical gases, and interacting quantum gases

    Science.gov (United States)

    Zhou, Chi-Chun; Dai, Wu-Sheng

    2018-02-01

    In statistical mechanics, for a system with a fixed number of particles, e.g. a finite-size system, strictly speaking, the thermodynamic quantity needs to be calculated in the canonical ensemble. Nevertheless, the calculation of the canonical partition function is difficult. In this paper, based on the mathematical theory of the symmetric function, we suggest a method for the calculation of the canonical partition function of ideal quantum gases, including ideal Bose, Fermi, and Gentile gases. Moreover, we express the canonical partition functions of interacting classical and quantum gases given by the classical and quantum cluster expansion methods in terms of the Bell polynomial in mathematics. The virial coefficients of ideal Bose, Fermi, and Gentile gases are calculated from the exact canonical partition function. The virial coefficients of interacting classical and quantum gases are calculated from the canonical partition function by using the expansion of the Bell polynomial, rather than calculated from the grand canonical potential.

  8. Summer-winter concentrations and gas-particle partitioning of short chain chlorinated paraffins in the atmosphere of an urban setting.

    Science.gov (United States)

    Wang, Thanh; Han, Shanlong; Yuan, Bo; Zeng, Lixi; Li, Yingming; Wang, Yawei; Jiang, Guibin

    2012-12-01

    Short chain chlorinated paraffins (SCCPs) are semi-volatile chemicals that are considered persistent in the environment, potential toxic and subject to long-range transport. This study investigates the concentrations and gas-particle partitioning of SCCPs at an urban site in Beijing during summer and wintertime. The total atmospheric SCCP levels ranged 1.9-33.0 ng/m(3) during wintertime. Significantly higher levels were found during the summer (range 112-332 ng/m(3)). The average fraction of total SCCPs in the particle phase (ϕ) was 0.67 during wintertime but decreased significantly during the summer (ϕ = 0.06). The ten and eleven carbon chain homologues with five to eight chlorine atoms were the predominant SCCP formula groups in air. Significant linear correlations were found between the gas-particle partition coefficients and the predicted subcooled vapor pressures and octanol-air partition coefficients. The gas-particle partitioning of SCCPs was further investigated and compared with both the Junge-Pankow adsorption and K(oa)-based absorption models. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Chains, antichains, and complements in infinite partition lattices

    DEFF Research Database (Denmark)

    Avery, James Emil; Moyen, Jean-Yves; Ruzicka, Pavel

    2018-01-01

    We consider the partition lattice $\\Pi_\\kappa$ on any set of transfinite cardinality $\\kappa$, and properties of $\\Pi_\\kappa$ whose analogues do not hold for finite cardinalities. Assuming the Axiom of Choice we prove: (I) the cardinality of any maximal well-ordered chain is between the cofinalit...

  10. QSPR modeling of octanol/water partition coefficient for vitamins by optimal descriptors calculated with SMILES.

    Science.gov (United States)

    Toropov, A A; Toropova, A P; Raska, I

    2008-04-01

    Simplified molecular input line entry system (SMILES) has been utilized in constructing quantitative structure-property relationships (QSPR) for octanol/water partition coefficient of vitamins and organic compounds of different classes by optimal descriptors. Statistical characteristics of the best model (vitamins) are the following: n=17, R(2)=0.9841, s=0.634, F=931 (training set); n=7, R(2)=0.9928, s=0.773, F=690 (test set). Using this approach for modeling octanol/water partition coefficient for a set of organic compounds gives a model that is statistically characterized by n=69, R(2)=0.9872, s=0.156, F=5184 (training set) and n=70, R(2)=0.9841, s=0.179, F=4195 (test set).

  11. Safety-Critical Partitioned Software Architecture: A Partitioned Software Architecture for Robotic

    Science.gov (United States)

    Horvath, Greg; Chung, Seung H.; Cilloniz-Bicchi, Ferner

    2011-01-01

    The flight software on virtually every mission currently managed by JPL has several major flaws that make it vulnerable to potentially fatal software defects. Many of these problems can be addressed by recently developed partitioned operating systems (OS). JPL has avoided adopting a partitioned operating system on its flight missions, primarily because doing so would require significant changes in flight software design, and the risks associated with changes of that magnitude cannot be accepted by an active flight project. The choice of a partitioned OS can have a dramatic effect on the overall system and software architecture, allowing for realization of benefits far beyond the concerns typically associated with the choice of OS. Specifically, we believe that a partitioned operating system, when coupled with an appropriate architecture, can provide a strong infrastructure for developing systems for which reusability, modifiability, testability, and reliability are essential qualities. By adopting a partitioned OS, projects can gain benefits throughout the entire development lifecycle, from requirements and design, all the way to implementation, testing, and operations.

  12. Cluster analysis of rural, urban, and curbside atmospheric particle size data.

    Science.gov (United States)

    Beddows, David C S; Dall'Osto, Manuel; Harrison, Roy M

    2009-07-01

    Particle size is a key determinant of the hazard posed by airborne particles. Continuous multivariate particle size data have been collected using aerosol particle size spectrometers sited at four locations within the UK: Harwell (Oxfordshire); Regents Park (London); British Telecom Tower (London); and Marylebone Road (London). These data have been analyzed using k-means cluster analysis, deduced to be the preferred cluster analysis technique, selected from an option of four partitional cluster packages, namelythe following: Fuzzy; k-means; k-median; and Model-Based clustering. Using cluster validation indices k-means clustering was shown to produce clusters with the smallest size, furthest separation, and importantly the highest degree of similarity between the elements within each partition. Using k-means clustering, the complexity of the data set is reduced allowing characterization of the data according to the temporal and spatial trends of the clusters. At Harwell, the rural background measurement site, the cluster analysis showed that the spectra may be differentiated by their modal-diameters and average temporal trends showing either high counts during the day-time or night-time hours. Likewise for the urban sites, the cluster analysis differentiated the spectra into a small number of size distributions according their modal-diameter, the location of the measurement site, and time of day. The responsible aerosol emission, formation, and dynamic processes can be inferred according to the cluster characteristics and correlation to concurrently measured meteorological, gas phase, and particle phase measurements.

  13. Polymers as reference partitioning phase: polymer calibration for an analytically operational approach to quantify multimedia phase partitioning

    DEFF Research Database (Denmark)

    Gilbert, Dorothea; Witt, Gesine; Smedes, Foppe

    2016-01-01

    Polymers are increasingly applied for the enrichment of hydrophobic organic chemicals (HOCs) from various types of samples and media in many analytical partitioning-based measuring techniques. We propose using polymers as a reference partitioning phase and introduce polymer-polymer partitioning......-air) and multimedia partition coefficients (lipid-water, air-water) were calculated by applying the new concept of a polymer as reference partitioning phase and by using polymer-polymer partition coefficients as conversion factors. The present study encourages the use of polymer-polymer partition coefficients...

  14. Cylindric partitions, {{\\boldsymbol{ W }}}_{r} characters and the Andrews-Gordon-Bressoud identities

    Science.gov (United States)

    Foda, O.; Welsh, T. A.

    2016-04-01

    We study the Andrews-Gordon-Bressoud (AGB) generalisations of the Rogers-Ramanujan q-series identities in the context of cylindric partitions. We recall the definition of r-cylindric partitions, and provide a simple proof of Borodin’s product expression for their generating functions, that can be regarded as a limiting case of an unpublished proof by Krattenthaler. We also recall the relationships between the r-cylindric partition generating functions, the principal characters of {\\hat{{sl}}}r algebras, the {{\\boldsymbol{ M }}}r r,r+d minimal model characters of {{\\boldsymbol{ W }}}r algebras, and the r-string abaci generating functions, providing simple proofs for each. We then set r = 2, and use two-cylindric partitions to re-derive the AGB identities as follows. Firstly, we use Borodin’s product expression for the generating functions of the two-cylindric partitions with infinitely long parts, to obtain the product sides of the AGB identities, times a factor {(q;q)}∞ -1, which is the generating function of ordinary partitions. Next, we obtain a bijection from the two-cylindric partitions, via two-string abaci, into decorated versions of Bressoud’s restricted lattice paths. Extending Bressoud’s method of transforming between restricted paths that obey different restrictions, we obtain sum expressions with manifestly non-negative coefficients for the generating functions of the two-cylindric partitions which contains a factor {(q;q)}∞ -1. Equating the product and sum expressions of the same two-cylindric partitions, and canceling a factor of {(q;q)}∞ -1 on each side, we obtain the AGB identities.

  15. Minimum nonuniform graph partitioning with unrelated weights

    Science.gov (United States)

    Makarychev, K. S.; Makarychev, Yu S.

    2017-12-01

    We give a bi-criteria approximation algorithm for the Minimum Nonuniform Graph Partitioning problem, recently introduced by Krauthgamer, Naor, Schwartz and Talwar. In this problem, we are given a graph G=(V,E) and k numbers ρ_1,\\dots, ρ_k. The goal is to partition V into k disjoint sets (bins) P_1,\\dots, P_k satisfying \\vert P_i\\vert≤ ρi \\vert V\\vert for all i, so as to minimize the number of edges cut by the partition. Our bi-criteria algorithm gives an O(\\sqrt{log \\vert V\\vert log k}) approximation for the objective function in general graphs and an O(1) approximation in graphs excluding a fixed minor. The approximate solution satisfies the relaxed capacity constraints \\vert P_i\\vert ≤ (5+ \\varepsilon)ρi \\vert V\\vert. This algorithm is an improvement upon the O(log \\vert V\\vert)-approximation algorithm by Krauthgamer, Naor, Schwartz and Talwar. We extend our results to the case of 'unrelated weights' and to the case of 'unrelated d-dimensional weights'. A preliminary version of this work was presented at the 41st International Colloquium on Automata, Languages and Programming (ICALP 2014). Bibliography: 7 titles.

  16. Polyacrylate–water partitioning of biocidal compounds: Enhancing the understanding of biocide partitioning between render and water

    DEFF Research Database (Denmark)

    Bollmann, Ulla E.; Ou, Yi; Mayer, Philipp

    2014-01-01

    -N-octylisothiazolinone). The correlation of the polyacrylate-water partition constants with the octanol-water partition constants is significant, but the polyacrylate-water partition constants were predominantly below octanol-water partition constants (Kow). The comparison with render-water distribution constants showed that estimating...

  17. RNA graph partitioning for the discovery of RNA modularity: a novel application of graph partition algorithm to biology.

    Directory of Open Access Journals (Sweden)

    Namhee Kim

    Full Text Available Graph representations have been widely used to analyze and design various economic, social, military, political, and biological networks. In systems biology, networks of cells and organs are useful for understanding disease and medical treatments and, in structural biology, structures of molecules can be described, including RNA structures. In our RNA-As-Graphs (RAG framework, we represent RNA structures as tree graphs by translating unpaired regions into vertices and helices into edges. Here we explore the modularity of RNA structures by applying graph partitioning known in graph theory to divide an RNA graph into subgraphs. To our knowledge, this is the first application of graph partitioning to biology, and the results suggest a systematic approach for modular design in general. The graph partitioning algorithms utilize mathematical properties of the Laplacian eigenvector (µ2 corresponding to the second eigenvalues (λ2 associated with the topology matrix defining the graph: λ2 describes the overall topology, and the sum of µ2's components is zero. The three types of algorithms, termed median, sign, and gap cuts, divide a graph by determining nodes of cut by median, zero, and largest gap of µ2's components, respectively. We apply these algorithms to 45 graphs corresponding to all solved RNA structures up through 11 vertices (∼ 220 nucleotides. While we observe that the median cut divides a graph into two similar-sized subgraphs, the sign and gap cuts partition a graph into two topologically-distinct subgraphs. We find that the gap cut produces the best biologically-relevant partitioning for RNA because it divides RNAs at less stable connections while maintaining junctions intact. The iterative gap cuts suggest basic modules and assembly protocols to design large RNA structures. Our graph substructuring thus suggests a systematic approach to explore the modularity of biological networks. In our applications to RNA structures, subgraphs

  18. Study of energy conversion and partitioning in the magnetic reconnection layer of a laboratory plasma

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masaaki; Yoo, Jongsoo; Jara-Almonte, Jonathan; Ji, Hantao; Kulsrud, Russell M.; Myers, Clayton E. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Daughton, William [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2015-05-15

    While the most important feature of magnetic reconnection is that it energizes plasma particles by converting magnetic energy to particle energy, the exact mechanisms by which this happens are yet to be determined despite a long history of reconnection research. Recently, we have reported our results on the energy conversion and partitioning in a laboratory reconnection layer in a short communication [Yamada et al., Nat. Commun. 5, 4474 (2014)]. The present paper is a detailed elaboration of this report together with an additional dataset with different boundary sizes. Our experimental study of the reconnection layer is carried out in the two-fluid physics regime where ions and electrons move quite differently. We have observed that the conversion of magnetic energy occurs across a region significantly larger than the narrow electron diffusion region. A saddle shaped electrostatic potential profile exists in the reconnection plane, and ions are accelerated by the resulting electric field at the separatrices. These accelerated ions are then thermalized by re-magnetization in the downstream region. A quantitative inventory of the converted energy is presented in a reconnection layer with a well-defined, variable boundary. We have also carried out a systematic study of the effects of boundary conditions on the energy inventory. This study concludes that about 50% of the inflowing magnetic energy is converted to particle energy, 2/3 of which is ultimately transferred to ions and 1/3 to electrons. Assisted by another set of magnetic reconnection experiment data and numerical simulations with different sizes of monitoring box, it is also observed that the observed features of energy conversion and partitioning do not depend on the size of monitoring boundary across the range of sizes tested from 1.5 to 4 ion skin depths.

  19. COSPEDTree: COuplet Supertree by Equivalence Partitioning of Taxa Set and DAG Formation.

    Science.gov (United States)

    Bhattacharyya, Sourya; Mukherjee, Jayanta

    2015-01-01

    From a set of phylogenetic trees with overlapping taxa set, a supertree exhibits evolutionary relationships among all input taxa. The key is to resolve the contradictory relationships with respect to input trees, between individual taxa subsets. Formulation of this NP hard problem employs either local search heuristics to reduce tree search space, or resolves the conflicts with respect to fixed or varying size subtree level decompositions. Different approximation techniques produce supertrees with considerable performance variations. Moreover, the majority of the algorithms involve high computational complexity, thus not suitable for use on large biological data sets. Current study presents COSPEDTree, a novel method for supertree construction. The technique resolves source tree conflicts by analyzing couplet (taxa pair) relationships for each source trees. Subsequently, individual taxa pairs are resolved with a single relation. To prioritize the consensus relations among individual taxa pairs for resolving them, greedy scoring is employed to assign higher score values for the consensus relations among a taxa pair. Selected set of relations resolving individual taxa pairs is subsequently used to construct a directed acyclic graph (DAG). Vertices of DAG represents a taxa subset inferred from the same speciation event. Thus, COSPEDTree can generate non-binary supertrees as well. Depth first traversal on this DAG yields final supertree. According to the performance metrics on branch dissimilarities (such as FP, FN and RF), COSPEDTree produces mostly conservative, well resolved supertrees. Specifically, RF metrics are mostly lower compared to the reference approaches, and FP values are lower apart from only strictly conservative (or veto) approaches. COSPEDTree has worst case time and space complexities of cubic and quadratic order, respectively, better or comparable to the reference approaches. Such high performance and low computational costs enable COSPEDTree to be

  20. The complex formation-partition and partition-association models of solvent extraction of ions

    International Nuclear Information System (INIS)

    Siekierski, S.

    1976-01-01

    Two models of the extraction process have been proposed. In the first model it is assumed that the partitioning neutral species is at first formed in the aqueous phase and then transferred into the organic phase. The second model is based on the assumption that equivalent amounts of cations are at first transferred from the aqueous into the organic phase and then associated to form a neutral molecule. The role of the solubility parameter in extraction and the relation between the solubility of liquid organic substances in water and the partition of complexes have been discussed. The extraction of simple complexes and complexes with organic ligands has been discussed using the first model. Partition coefficients have been calculated theoretically and compared with experimental values in some very simple cases. The extraction of ion pairs has been discussed using the partition-association model and the concept of single-ion partition coefficients. (author)

  1. Optimization of Solar Water Heating System under Time and Spatial Partition Heating in Rural Dwellings

    Directory of Open Access Journals (Sweden)

    Yanfeng Liu

    2017-10-01

    Full Text Available This paper proposes the application of time and spatial partition heating to a solar water heating system. The heating effect and system performance were analyzed under the continuous and whole space heating and time and spatial partition heating using TRNSYS. The results were validated by comparing with the test results of the demonstration building. Compared to continuous and whole space heating, the use of time and spatial partition heating increases the solar fraction by 16.5%, reduces the auxiliary heating by 7390 MJ, and reduces the annual operation cost by 2010 RMB. Under time and spatial partition heating, optimization analyses were conducted for the two system capacity parameters of the solar collector area and tank volume and the one operation parameter of auxiliary heater setting outlet temperature. The results showed that a reasonable choice of the solar collector area can reduce the dynamic annual cost, the increased tank volume is advantageous to heat storage, and the auxiliary heater setting outlet temperature have greater influence on the indoor heating effect. The advanced opening of solar water heating system and the normal opening of passive air vents are recommended. Based on the comparison of the two modes, the time and spatial partition heating technology is a better choice for rural dwellings.

  2. COMPUTING VERTICES OF INTEGER PARTITION POLYTOPES

    Directory of Open Access Journals (Sweden)

    A. S. Vroublevski

    2015-01-01

    Full Text Available The paper describes a method of generating vertices of the polytopes of integer partitions that was used by the authors to calculate all vertices and support vertices of the partition polytopes for all n ≤ 105 and all knapsack partitions of n ≤ 165. The method avoids generating all partitions of n. The vertices are determined with the help of sufficient and necessary conditions; in the hard cases, the well-known program Polymake is used. Some computational aspects are exposed in more detail. These are the algorithm for checking the criterion that characterizes partitions that are convex combinations of two other partitions; the way of using two combinatorial operations that transform the known vertices to the new ones; and employing the Polymake to recognize a limited number (for small n of partitions that need three or more other partitions for being convexly expressed. We discuss the computational results on the numbers of vertices and support vertices of the partition polytopes and some appealing problems these results give rise to.

  3. Exact Cover Problem in Milton Babbitt's All-partition Array

    DEFF Research Database (Denmark)

    Bemman, Brian; Meredith, David

    2015-01-01

    One aspect of analyzing Milton Babbitt’s (1916–2011) all- partition arrays requires finding a sequence of distinct, non-overlapping aggregate regions that completely and exactly covers an irregular matrix of pitch class integers. This is an example of the so-called exact cover problem. Given a set...

  4. Combining the role of convenience and consideration set size in explaining fish consumption in Norway.

    Science.gov (United States)

    Rortveit, Asbjorn Warvik; Olsen, Svein Ottar

    2009-04-01

    The purpose of this study is to explore how convenience orientation, perceived product inconvenience and consideration set size are related to attitudes towards fish and fish consumption. The authors present a structural equation model (SEM) based on the integration of two previous studies. The results of a SEM analysis using Lisrel 8.72 on data from a Norwegian consumer survey (n=1630) suggest that convenience orientation and perceived product inconvenience have a negative effect on both consideration set size and consumption frequency. Attitude towards fish has the greatest impact on consumption frequency. The results also indicate that perceived product inconvenience is a key variable since it has a significant impact on attitude, and on consideration set size and consumption frequency. Further, the analyses confirm earlier findings suggesting that the effect of convenience orientation on consumption is partially mediated through perceived product inconvenience. The study also confirms earlier findings suggesting that the consideration set size affects consumption frequency. Practical implications drawn from this research are that the seafood industry would benefit from developing and positioning products that change beliefs about fish as an inconvenient product. Future research for other food categories should be done to enhance the external validity.

  5. The total position-spread tensor: Spin partition

    International Nuclear Information System (INIS)

    El Khatib, Muammar; Evangelisti, Stefano; Leininger, Thierry; Brea, Oriana; Fertitta, Edoardo; Bendazzoli, Gian Luigi

    2015-01-01

    The Total Position Spread (TPS) tensor, defined as the second moment cumulant of the position operator, is a key quantity to describe the mobility of electrons in a molecule or an extended system. In the present investigation, the partition of the TPS tensor according to spin variables is derived and discussed. It is shown that, while the spin-summed TPS gives information on charge mobility, the spin-partitioned TPS tensor becomes a powerful tool that provides information about spin fluctuations. The case of the hydrogen molecule is treated, both analytically, by using a 1s Slater-type orbital, and numerically, at Full Configuration Interaction (FCI) level with a V6Z basis set. It is found that, for very large inter-nuclear distances, the partitioned tensor growths quadratically with the distance in some of the low-lying electronic states. This fact is related to the presence of entanglement in the wave function. Non-dimerized open chains described by a model Hubbard Hamiltonian and linear hydrogen chains H n (n ≥ 2), composed of equally spaced atoms, are also studied at FCI level. The hydrogen systems show the presence of marked maxima for the spin-summed TPS (corresponding to a high charge mobility) when the inter-nuclear distance is about 2 bohrs. This fact can be associated to the presence of a Mott transition occurring in this region. The spin-partitioned TPS tensor, on the other hand, has a quadratical growth at long distances, a fact that corresponds to the high spin mobility in a magnetic system

  6. Partitioning of Iron and Scandium in Soils Having Water Drainage Limitations

    International Nuclear Information System (INIS)

    Aide, M.; Braden, I.; Mueller, W.

    2010-01-01

    Soil chemistry of Fe includes weathering reactions, adsorption, hydrolysis, complexation, and oxidation-reduction reactions. Soil chemistry for scandium (Sc) is similar, but Sc does not include oxidation-reduction reactions. To determine if geochemical analysis may be used to identify Sc partitioning with respect to Fe among the particle size fractions, two Alfisol and two Ultisol soils were assessed using an aqua-regia digestion to estimate Sc and Fe concentrations for whole soil and particle size separates. Aqua-regia digestion data showed Sc depletion relative to Fe in sand separate. Sand separate is largely composed on quartz sand and Fe-Mn-bearing nodules, which are redoximorphic features produced by alternating oxic and suboxic/anoxic conditions associated with seasonally fluctuating water tables. Relative partitioning of Fe and Sc in these soils warrants further study to assess if selective extractions could quantify the extent of modern or ancestral oxidation-reduction processes responsible in some soil features involved in soil genesis.

  7. The prevalence of terraced treescapes in analyses of phylogenetic data sets.

    Science.gov (United States)

    Dobrin, Barbara H; Zwickl, Derrick J; Sanderson, Michael J

    2018-04-04

    The pattern of data availability in a phylogenetic data set may lead to the formation of terraces, collections of equally optimal trees. Terraces can arise in tree space if trees are scored with parsimony or with partitioned, edge-unlinked maximum likelihood. Theory predicts that terraces can be large, but their prevalence in contemporary data sets has never been surveyed. We selected 26 data sets and phylogenetic trees reported in recent literature and investigated the terraces to which the trees would belong, under a common set of inference assumptions. We examined terrace size as a function of the sampling properties of the data sets, including taxon coverage density (the proportion of taxon-by-gene positions with any data present) and a measure of gene sampling "sufficiency". We evaluated each data set in relation to the theoretical minimum gene sampling depth needed to reduce terrace size to a single tree, and explored the impact of the terraces found in replicate trees in bootstrap methods. Terraces were identified in nearly all data sets with taxon coverage densities tree. Terraces found during bootstrap resampling reduced overall support. If certain inference assumptions apply, trees estimated from empirical data sets often belong to large terraces of equally optimal trees. Terrace size correlates to data set sampling properties. Data sets seldom include enough genes to reduce terrace size to one tree. When bootstrap replicate trees lie on a terrace, statistical support for phylogenetic hypotheses may be reduced. Although some of the published analyses surveyed were conducted with edge-linked inference models (which do not induce terraces), unlinked models have been used and advocated. The present study describes the potential impact of that inference assumption on phylogenetic inference in the context of the kinds of multigene data sets now widely assembled for large-scale tree construction.

  8. Space-partition method for the variance-based sensitivity analysis: Optimal partition scheme and comparative study

    International Nuclear Information System (INIS)

    Zhai, Qingqing; Yang, Jun; Zhao, Yu

    2014-01-01

    Variance-based sensitivity analysis has been widely studied and asserted itself among practitioners. Monte Carlo simulation methods are well developed in the calculation of variance-based sensitivity indices but they do not make full use of each model run. Recently, several works mentioned a scatter-plot partitioning method to estimate the variance-based sensitivity indices from given data, where a single bunch of samples is sufficient to estimate all the sensitivity indices. This paper focuses on the space-partition method in the estimation of variance-based sensitivity indices, and its convergence and other performances are investigated. Since the method heavily depends on the partition scheme, the influence of the partition scheme is discussed and the optimal partition scheme is proposed based on the minimized estimator's variance. A decomposition and integration procedure is proposed to improve the estimation quality for higher order sensitivity indices. The proposed space-partition method is compared with the more traditional method and test cases show that it outperforms the traditional one

  9. Determinants of Awareness, Consideration, and Choice Set Size in University Choice.

    Science.gov (United States)

    Dawes, Philip L.; Brown, Jennifer

    2002-01-01

    Developed and tested a model of students' university "brand" choice using five individual-level variables (ethnic group, age, gender, number of parents going to university, and academic ability) and one situational variable (duration of search) to explain variation in the sizes of awareness, consideration, and choice decision sets. (EV)

  10. Determination of size-specific exposure settings in dental cone-beam CT

    International Nuclear Information System (INIS)

    Pauwels, Ruben; Jacobs, Reinhilde; Bogaerts, Ria; Bosmans, Hilde; Panmekiate, Soontra

    2017-01-01

    To estimate the possible reduction of tube output as a function of head size in dental cone-beam computed tomography (CBCT). A 16 cm PMMA phantom, containing a central and six peripheral columns filled with PMMA, was used to represent an average adult male head. The phantom was scanned using CBCT, with 0-6 peripheral columns having been removed in order to simulate varying head sizes. For five kV settings (70-90 kV), the mAs required to reach a predetermined image noise level was determined, and corresponding radiation doses were derived. Results were expressed as a function of head size, age, and gender, based on growth reference charts. The use of 90 kV consistently resulted in the largest relative dose reduction. A potential mAs reduction ranging from 7 % to 50 % was seen for the different simulated head sizes, showing an exponential relation between head size and mAs. An optimized exposure protocol based on head circumference or age/gender is proposed. A considerable dose reduction, through reduction of the mAs rather than the kV, is possible for small-sized patients in CBCT, including children and females. Size-specific exposure protocols should be clinically implemented. (orig.)

  11. Determination of size-specific exposure settings in dental cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Pauwels, Ruben [Chulalongkorn University, Department of Radiology, Faculty of Dentistry, Patumwan, Bangkok (Thailand); University of Leuven, OMFS-IMPATH Research Group, Department of Imaging and Pathology, Biomedical Sciences Group, Leuven (Belgium); Jacobs, Reinhilde [University of Leuven, OMFS-IMPATH Research Group, Department of Imaging and Pathology, Biomedical Sciences Group, Leuven (Belgium); Bogaerts, Ria [University of Leuven, Laboratory of Experimental Radiotherapy, Department of Oncology, Biomedical Sciences Group, Leuven (Belgium); Bosmans, Hilde [University of Leuven, Medical Physics and Quality Assessment, Department of Imaging and Pathology, Biomedical Sciences Group, Leuven (Belgium); Panmekiate, Soontra [Chulalongkorn University, Department of Radiology, Faculty of Dentistry, Patumwan, Bangkok (Thailand)

    2017-01-15

    To estimate the possible reduction of tube output as a function of head size in dental cone-beam computed tomography (CBCT). A 16 cm PMMA phantom, containing a central and six peripheral columns filled with PMMA, was used to represent an average adult male head. The phantom was scanned using CBCT, with 0-6 peripheral columns having been removed in order to simulate varying head sizes. For five kV settings (70-90 kV), the mAs required to reach a predetermined image noise level was determined, and corresponding radiation doses were derived. Results were expressed as a function of head size, age, and gender, based on growth reference charts. The use of 90 kV consistently resulted in the largest relative dose reduction. A potential mAs reduction ranging from 7 % to 50 % was seen for the different simulated head sizes, showing an exponential relation between head size and mAs. An optimized exposure protocol based on head circumference or age/gender is proposed. A considerable dose reduction, through reduction of the mAs rather than the kV, is possible for small-sized patients in CBCT, including children and females. Size-specific exposure protocols should be clinically implemented. (orig.)

  12. Region-based Image Segmentation by Watershed Partition and DCT Energy Compaction

    Directory of Open Access Journals (Sweden)

    Chi-Man Pun

    2012-02-01

    Full Text Available An image segmentation approach by improved watershed partition and DCT energy compaction has been proposed in this paper. The proposed energy compaction, which expresses the local texture of an image area, is derived by exploiting the discrete cosine transform. The algorithm is a hybrid segmentation technique which is composed of three stages. First, the watershed transform is utilized by preprocessing techniques: edge detection and marker in order to partition the image in to several small disjoint patches, while the region size, mean and variance features are used to calculate region cost for combination. Then in the second merging stage the DCT transform is used for energy compaction which is a criterion for texture comparison and region merging. Finally the image can be segmented into several partitions. The experimental results show that the proposed approach achieved very good segmentation robustness and efficiency, when compared to other state of the art image segmentation algorithms and human segmentation results.

  13. Determination of partition behavior of organic surrogates between paperboard packaging materials and air.

    Science.gov (United States)

    Triantafyllou, V I; Akrida-Demertzi, K; Demertzis, P G

    2005-06-03

    The suitability of recycled paperboard packaging materials for direct food contact applications is a major area of investigation. Chemical contaminants (surrogates) partitioning between recycled paper packaging and foods may affect the safety and health of the consumer. The partition behavior of all possible organic compounds between cardboards and individual foodstuffs is difficult and too time consuming for being fully investigated. Therefore it may be more efficient to determine these partition coefficients indirectly through experimental determination of the partitioning behavior between cardboard samples and air. In this work, the behavior of organic pollutants present in a set of two paper and board samples intended to be in contact with foods was studied. Adsorption isotherms have been plotted and partition coefficients between paper and air have been calculated as a basis for the estimation of their migration potential into food. Values of partition coefficients (Kpaper/air) from 47 to 1207 were obtained at different temperatures. For the less volatile surrogates such as dibutyl phthalate and methyl stearate higher Kpaper/air values were obtained. The adsorption curves showed that the more volatile substances are partitioning mainly in air phase and increasing the temperature from 70 to 100 degrees C their concentrations in air (Cair) have almost doubled. The analysis of surrogates was performed with a method based on solvent extraction and gas chromatographic-flame ionization detection (GC-FID) quantification.

  14. Partitioned based approach for very large scale database in Indian nuclear power plants

    International Nuclear Information System (INIS)

    Tiwari, Sachin; Upadhyay, Pushp; Sengupta, Nabarun; Bhandarkar, S.G.; Agilandaeswari

    2012-01-01

    This paper presents a partition based approach for handling very large tables with size running in giga-bytes to tera-bytes. The scheme is developed from our experience in handling large signal storage which is required in various computer based data acquisition and control room operator information systems such as Distribution Recording System (DRS) and Computerised Operator Information System (COIS). Whenever there is a disturbance in an operating nuclear power plant, it triggers an action where a large volume of data from multiple sources is generated and this data needs to be stored. Concurrency issues as data is from multiple sources and very large amount of data are the problems which are addressed in this paper by applying partition based approach. Advantages of partition based approach with other techniques are discussed. (author)

  15. Auditory proactive interference in monkeys: the roles of stimulus set size and intertrial interval.

    Science.gov (United States)

    Bigelow, James; Poremba, Amy

    2013-09-01

    We conducted two experiments to examine the influences of stimulus set size (the number of stimuli that are used throughout the session) and intertrial interval (ITI, the elapsed time between trials) in auditory short-term memory in monkeys. We used an auditory delayed matching-to-sample task wherein the animals had to indicate whether two sounds separated by a 5-s retention interval were the same (match trials) or different (nonmatch trials). In Experiment 1, we randomly assigned stimulus set sizes of 2, 4, 8, 16, 32, 64, or 192 (trial-unique) for each session of 128 trials. Consistent with previous visual studies, overall accuracy was consistently lower when smaller stimulus set sizes were used. Further analyses revealed that these effects were primarily caused by an increase in incorrect "same" responses on nonmatch trials. In Experiment 2, we held the stimulus set size constant at four for each session and alternately set the ITI at 5, 10, or 20 s. Overall accuracy improved when the ITI was increased from 5 to 10 s, but it was the same across the 10- and 20-s conditions. As in Experiment 1, the overall decrease in accuracy during the 5-s condition was caused by a greater number of false "match" responses on nonmatch trials. Taken together, Experiments 1 and 2 showed that auditory short-term memory in monkeys is highly susceptible to proactive interference caused by stimulus repetition. Additional analyses of the data from Experiment 1 suggested that monkeys may make same-different judgments on the basis of a familiarity criterion that is adjusted by error-related feedback.

  16. Constraint Programming Approach to the Problem of Generating Milton Babbitt's All-partition Arrays

    DEFF Research Database (Denmark)

    Tanaka, Tsubasa; Bemman, Brian; Meredith, David

    2016-01-01

    elements and corresponding to a distinct integer partition of 12. Constraint programming (CP) is a tool for solving such combinatorial and constraint satisfaction problems. In this paper, we use CP for the first time to formalize this problem in generating an all-partition array. Solving the whole...... of this problem is difficult and few known solutions exist. Therefore, we propose solving two sub-problems and joining these to form a complete solution. We conclude by presenting a solution found using this method. Our solution is the first we are aware of to be discovered automatically using a computer......Milton Babbitt (1916–2011) was a composer of twelve-tone serial music noted for creating the all-partition array. One part of the problem in generating an all-partition array requires finding a covering of a pitch-class matrix by a collection of sets, each forming a region containing 12 distinct...

  17. Partitioning in P-T concept

    International Nuclear Information System (INIS)

    Zhang Peilu; Qi Zhanshun; Zhu Zhixuan

    2000-01-01

    Comparison of dry- and water-method for partitioning fission products and minor actinides from the spent fuels, and description of advance of dry-method were done. Partitioning process, some typical concept and some results of dry-method were described. The problems fond in dry-method up to now were pointed out. The partitioning study program was suggested

  18. Coexistence via resource partitioning fails to generate an increase in community function.

    Directory of Open Access Journals (Sweden)

    John P DeLong

    Full Text Available Classic ecological theory suggests that resource partitioning facilitates the coexistence of species by reducing inter-specific competition. A byproduct of this process is an increase in overall community function, because a greater spectrum of resources can be used. In contrast, coexistence facilitated by neutral mechanisms is not expected to increase function. We studied coexistence in laboratory microcosms of the bactivorous ciliates Paramecium aurelia and Colpidium striatum to understand the relationship between function and coexistence mechanism. We quantified population and community-level function (biomass and oxygen consumption, competitive interactions, and resource partitioning. The two ciliates partitioned their bacterial resource along a size axis, with the larger ciliate consuming larger bacteria than the smaller ciliate. Despite this, there was no gain in function at the community level for either biomass or oxygen consumption, and competitive effects were symmetrical within and between species. Because other potential coexistence mechanisms can be ruled out, it is likely that inter-specific interference competition diminished the expected gain in function generated by resource partitioning, leading to a system that appeared competitively neutral even when structured by niche partitioning. We also analyzed several previous studies where two species of protists coexisted and found that the two-species communities showed a broad range of biomass levels relative to the single-species states.

  19. The reconstruction of choice value in the brain: a look into the size of consideration sets and their affective consequences.

    Science.gov (United States)

    Kim, Hye-Young; Shin, Yeonsoon; Han, Sanghoon

    2014-04-01

    It has been proposed that choice utility exhibits an inverted U-shape as a function of the number of options in the choice set. However, most researchers have so far only focused on the "physically extant" number of options in the set while disregarding the more important psychological factor, the "subjective" number of options worth considering to choose-that is, the size of the consideration set. To explore this previously ignored aspect, we examined how variations in the size of a consideration set can produce different affective consequences after making choices and investigated the underlying neural mechanism using fMRI. After rating their preferences for art posters, participants made a choice from a presented set and then reported on their level of satisfaction with their choice and the level of difficulty experienced in choosing it. Our behavioral results demonstrated that enlarged assortment set can lead to greater choice satisfaction only when increases in both consideration set size and preference contrast are involved. Moreover, choice difficulty is determined based on the size of an individual's consideration set rather than on the size of the assortment set, and it decreases linearly as a function of the level of contrast among alternatives. The neuroimaging analysis of choice-making revealed that subjective consideration set size was encoded in the striatum, the dACC, and the insula. In addition, the striatum also represented variations in choice satisfaction resulting from alterations in the size of consideration sets, whereas a common neural specificity for choice difficulty and consideration set size was shown in the dACC. These results have theoretical and practical importance in that it is one of the first studies investigating the influence of the psychological attributes of choice sets on the value-based decision-making process.

  20. Covariance Partition Priors: A Bayesian Approach to Simultaneous Covariance Estimation for Longitudinal Data.

    Science.gov (United States)

    Gaskins, J T; Daniels, M J

    2016-01-02

    The estimation of the covariance matrix is a key concern in the analysis of longitudinal data. When data consists of multiple groups, it is often assumed the covariance matrices are either equal across groups or are completely distinct. We seek methodology to allow borrowing of strength across potentially similar groups to improve estimation. To that end, we introduce a covariance partition prior which proposes a partition of the groups at each measurement time. Groups in the same set of the partition share dependence parameters for the distribution of the current measurement given the preceding ones, and the sequence of partitions is modeled as a Markov chain to encourage similar structure at nearby measurement times. This approach additionally encourages a lower-dimensional structure of the covariance matrices by shrinking the parameters of the Cholesky decomposition toward zero. We demonstrate the performance of our model through two simulation studies and the analysis of data from a depression study. This article includes Supplementary Material available online.

  1. Determining an Estimate of an Equivalence Relation for Moderate and Large Sized Sets

    Directory of Open Access Journals (Sweden)

    Leszek Klukowski

    2017-01-01

    Full Text Available This paper presents two approaches to determining estimates of an equivalence relation on the basis of pairwise comparisons with random errors. Obtaining such an estimate requires the solution of a discrete programming problem which minimizes the sum of the differences between the form of the relation and the comparisons. The problem is NP hard and can be solved with the use of exact algorithms for sets of moderate size, i.e. about 50 elements. In the case of larger sets, i.e. at least 200 comparisons for each element, it is necessary to apply heuristic algorithms. The paper presents results (a statistical preprocessing, which enable us to determine the optimal or a near-optimal solution with acceptable computational cost. They include: the development of a statistical procedure producing comparisons with low probabilities of errors and a heuristic algorithm based on such comparisons. The proposed approach guarantees the applicability of such estimators for any size of set. (original abstract

  2. Partitioning planning studies: Preliminary evaluation of metal and radionuclide partitioning the high-temperature thermal treatment systems

    International Nuclear Information System (INIS)

    Liekhus, K.; Grandy, J.; Chambers, A.

    1997-03-01

    A preliminary study of toxic metals and radionuclide partitioning during high-temperature processing of mixed waste has been conducted during Fiscal Year 1996 within the Environmental Management Technology Evaluation Project. The study included: (a) identification of relevant partitioning mechanisms that cause feed material to be distributed between the solid, molten, and gas phases within a thermal treatment system; (b) evaluations of existing test data from applicable demonstration test programs as a means to identify and understand elemental and species partitioning; and, (c) evaluation of theoretical or empirical partitioning models for use in predicting elemental or species partitioning in a thermal treatment system. This preliminary study was conducted to identify the need for and the viability of developing the tools capable of describing and predicting toxic metals and radionuclide partitioning in the most applicable mixed waste thermal treatment processes. This document presents the results and recommendations resulting from this study that may serve as an impetus for developing and implementing these predictive tools

  3. Partitioning planning studies: Preliminary evaluation of metal and radionuclide partitioning the high-temperature thermal treatment systems

    Energy Technology Data Exchange (ETDEWEB)

    Liekhus, K.; Grandy, J.; Chambers, A. [and others

    1997-03-01

    A preliminary study of toxic metals and radionuclide partitioning during high-temperature processing of mixed waste has been conducted during Fiscal Year 1996 within the Environmental Management Technology Evaluation Project. The study included: (a) identification of relevant partitioning mechanisms that cause feed material to be distributed between the solid, molten, and gas phases within a thermal treatment system; (b) evaluations of existing test data from applicable demonstration test programs as a means to identify and understand elemental and species partitioning; and, (c) evaluation of theoretical or empirical partitioning models for use in predicting elemental or species partitioning in a thermal treatment system. This preliminary study was conducted to identify the need for and the viability of developing the tools capable of describing and predicting toxic metals and radionuclide partitioning in the most applicable mixed waste thermal treatment processes. This document presents the results and recommendations resulting from this study that may serve as an impetus for developing and implementing these predictive tools.

  4. The Euler–Riemann gases, and partition identities

    International Nuclear Information System (INIS)

    Chair, Noureddine

    2013-01-01

    The Euler theorem in partition theory and its generalization are derived from a non-interacting quantum field theory in which each bosonic mode with a given frequency is equivalent to a sum of bosonic mode whose frequency is twice (s-times) as much, and a fermionic (parafermionic) mode with the same frequency. Explicit formulas for the graded parafermionic partition functions are obtained, and the inverse of the graded partition function (IGPPF), turns out to be bosonic (fermionic) partition function depending on the parity of the order s of the parafermions. It is also shown that these partition functions are generating functions of partitions of integers with restrictions, the Euler generating function is identified with the inverse of the graded parafermionic partition function of order 2. As a result we obtain new sequences of partitions of integers with given restrictions. If the parity of the order s is even, then mixing a system of parafermions with a system whose partition function is (IGPPF), results in a system of fermions and bosons. On the other hand, if the parity of s is odd, then, the system we obtain is still a mixture of fermions and bosons but the corresponding Fock space of states is truncated. It turns out that these partition functions are given in terms of the Jacobi theta function θ 4 , and generate sequences in partition theory. Our partition functions coincide with the overpartitions of Corteel and Lovejoy, and jagged partitions in conformal field theory. Also, the partition functions obtained are related to the Ramond characters of the superconformal minimal models, and in the counting of the Moore–Read edge spectra that appear in the fractional quantum Hall effect. The different partition functions for the Riemann gas that are the counter parts of the Euler gas are obtained by a simple change of variables. In particular the counter part of the Jacobi theta function is (ζ(2t))/(ζ(t) 2 ) . Finally, we propose two formulas which brings

  5. Some application of the model of partition points on a one-dimensional lattice

    International Nuclear Information System (INIS)

    Mejdani, R.

    1991-07-01

    We have shown that by using a model of the gas of partition points on one-dimensional lattice, we can find some results about the enzyme kinetics or the average domain-size, which we have obtained before by using a correlated Walks' theory or a probabilistic (combinatoric) way. We have discussed also the problem related with the spread of an infection of disease and the stochastic model of partition points. We think that this model, as a very simple model and mathematically transparent, can be advantageous for other theoretical investigations in chemistry or modern biology. (author). 14 refs, 6 figs, 1 tab

  6. Hawk: A Runtime System for Partitioned Objects

    NARCIS (Netherlands)

    Ben Hassen, S.; Bal, H.E.; Tanenbaum, A.S.

    1997-01-01

    Hawk is a language-independent runtime system for writing data-parallel programs using partitioned objects. A partitioned object is a multidimensional array of elements that can be partitioned and distributed by the programmer. The Hawk runtime system uses the user-defined partitioning of objects

  7. Conformal partition functions of critical percolation from D 3 thermodynamic Bethe Ansatz equations

    Science.gov (United States)

    Morin-Duchesne, Alexi; Klümper, Andreas; Pearce, Paul A.

    2017-08-01

    Using the planar Temperley-Lieb algebra, critical bond percolation on the square lattice can be reformulated as a loop model. In this form, it is incorporated as {{ L}}{{ M}}(2, 3) in the Yang-Baxter integrable family of logarithmic minimal models {{ L}}{{ M}}( p, p\\prime) . We consider this model of percolation in the presence of boundaries and with periodic boundary conditions. Inspired by Kuniba, Sakai and Suzuki, we rewrite the recently obtained infinite Y-system of functional equations. In this way, we obtain nonlinear integral equations in the form of a closed finite set of TBA equations described by a D 3 Dynkin diagram. Following the methods of Klümper and Pearce, we solve the TBA equations for the conformal finite-size corrections. For the ground states of the standard modules on the strip, these agree with the known central charge c  =  0 and conformal weights Δ1, s for \\renewcommand≥≥slant} s\\in {{ Z}≥slant 1} with Δr, s=\\big((3r-2s){\\hspace{0pt}}^2-1\\big)/24 . For the periodic case, the finite-size corrections agree with the conformal weights Δ0, s , Δ1, s with \\renewcommand{≥{≥slant} s\\in\\frac{1}{2}{{ Z}≥slant 0} . These are obtained analytically using Rogers dilogarithm identities. We incorporate all finite excitations by formulating empirical selection rules for the patterns of zeros of all the eigenvalues of the standard modules. We thus obtain the conformal partition functions on the cylinder and the modular invariant partition function (MIPF) on the torus. By applying q-binomial and q-Narayana identities, it is shown that our refined finitized characters on the strip agree with those of Pearce, Rasmussen and Zuber. For percolation on the torus, the MIPF is a non-diagonal sesquilinear form in affine u(1) characters given by the u(1) partition function Z2, 3(q)=Z2, 3{Circ}(q) . The u(1) operator content is {{ N}}Δ, \\barΔ=1 for Δ=\\barΔ=-\\frac{1}{24}, \\frac{35}{24} and {{ N}}Δ, \\barΔ=2 for

  8. [On the partition of acupuncture academic schools].

    Science.gov (United States)

    Yang, Pengyan; Luo, Xi; Xia, Youbing

    2016-05-01

    Nowadays extensive attention has been paid on the research of acupuncture academic schools, however, a widely accepted method of partition of acupuncture academic schools is still in need. In this paper, the methods of partition of acupuncture academic schools in the history have been arranged, and three typical methods of"partition of five schools" "partition of eighteen schools" and "two-stage based partition" are summarized. After adeep analysis on the disadvantages and advantages of these three methods, a new method of partition of acupuncture academic schools that is called "three-stage based partition" is proposed. In this method, after the overall acupuncture academic schools are divided into an ancient stage, a modern stage and a contemporary stage, each schoolis divided into its sub-school category. It is believed that this method of partition can remedy the weaknesses ofcurrent methods, but also explore a new model of inheritance and development under a different aspect through thedifferentiation and interaction of acupuncture academic schools at three stages.

  9. Cation solvation with quantum chemical effects modeled by a size-consistent multi-partitioning quantum mechanics/molecular mechanics method.

    Science.gov (United States)

    Watanabe, Hiroshi C; Kubillus, Maximilian; Kubař, Tomáš; Stach, Robert; Mizaikoff, Boris; Ishikita, Hiroshi

    2017-07-21

    In the condensed phase, quantum chemical properties such as many-body effects and intermolecular charge fluctuations are critical determinants of the solvation structure and dynamics. Thus, a quantum mechanical (QM) molecular description is required for both solute and solvent to incorporate these properties. However, it is challenging to conduct molecular dynamics (MD) simulations for condensed systems of sufficient scale when adapting QM potentials. To overcome this problem, we recently developed the size-consistent multi-partitioning (SCMP) quantum mechanics/molecular mechanics (QM/MM) method and realized stable and accurate MD simulations, using the QM potential to a benchmark system. In the present study, as the first application of the SCMP method, we have investigated the structures and dynamics of Na + , K + , and Ca 2+ solutions based on nanosecond-scale sampling, a sampling 100-times longer than that of conventional QM-based samplings. Furthermore, we have evaluated two dynamic properties, the diffusion coefficient and difference spectra, with high statistical certainty. Furthermore the calculation of these properties has not previously been possible within the conventional QM/MM framework. Based on our analysis, we have quantitatively evaluated the quantum chemical solvation effects, which show distinct differences between the cations.

  10. Analysis of load balance in hybrid partitioning | Talib | Botswana ...

    African Journals Online (AJOL)

    In information retrieval systems, there are three types of index partitioning schemes - term partitioning, document partitioning, and hybrid partitioning. The hybrid-partitioning scheme combines both term and document partitioning schemes. Term partitioning provides high concurrency, which means that queries can be ...

  11. Radioactivity partitioning in incinerators for miscellaneous low-level wastes

    International Nuclear Information System (INIS)

    Kyle, S.; Bellinger, E.

    1988-03-01

    Her Majesty's Inspectorate of Pollution (HMIP) authorises the use of hospital, university and Local Authority incinerators for the disposal of solid radioactive wastes. At present these authorisations are calculated on ''worst case'' assumptions, this report aims to review the experimental data on radioactivity partitioning in these incinerators, in order to improve the accuracy of HMIP predictions. The types of radionuclides used in medicine were presented and it is noted there is no literature on the composition of university waste. The different types of incinerators are detailed, with diagrams. Major differences in design are apparent, particularly the offgas cleaning equipment in nuclear incinerators which hinders comparisons with institutional incinerators. A comprehensive literature review revealed 17 references on institutional radioactive waste incineration, 11 of these contained data sets. The partitioning experiments were described and show a wide range of methodology from incinerating guinea pigs to filter papers. In general, only ash composition data were presented, with no details of emissions or plating out in the incinerator. Thus the data sets were incomplete, often with a poor degree of accuracy. The data sets contained information on 40 elements; those were compared and general trends were apparent such as the absence of H-3, C-14 and I-125 in the ash in contrast to the high retention of Sc-46. Large differences between data sets were noted for P-32, Sr-85 and Sn-113 and within one experiment for S-35. (author)

  12. Unpartitioned versus incompletely partitioned cochleae: radiologic differentiation.

    Science.gov (United States)

    Sennaroglu, Levent; Saatci, Isil

    2004-07-01

    In the process of evaluating our patients, we realized that the term "Mondini deformity" was being used to describe two different types of incomplete partition of the cochlea. THE First one consisted of an unpartitioned, completely empty cochlea where the interscalar septum and entire modiolus were absent, giving the cochlea a cystic appearance; a grossly dilated vestibule accompanied this lesion. The second pathology fitted the classic description of Mondini deformity, consisting of a normal basal turn and cystic apex (where the middle and apical turns form a cystic cavity), dilated vestibule, and enlarged vestibular aqueduct. This study was planned to investigate the differences between the two types of incomplete partition for inner ear malformations based on radiologic features. We conducted a retrospective review of temporal bone computed tomography (CT) findings. The subjects were 18 patients with profound bilateral sensorineural hearing loss who had high-resolution CT with contiguous 1-mm thick images obtained through the petrous bone in axial sections. The CT results were reviewed as incomplete partition type I (IP-I) and type II (IP-II). Incomplete partition type I (unpartitioned cochlea, cystic cochleovestibular malformation) is defined as a malformation in which the cochlea lacks the entire modiolus and interscalar septa, resulting in a cystic appearance and there is an accompanying grossly dilated vestibule. In incomplete partition type II (incompletely partitioned cochlea, the Mondini deformity), there is a cochlea comprised of a normal basal turn and cystic apex accompanied by a minimally dilated vestibule and enlarged vestibular aqueduct (VA). Measurements involving the cochlea, vestibule, vestibular aqueduct, and internal auditory canal (IAC) were done to determine the characteristic features of these pathologies. : Thirteen ears had IP-I and 18 ears had IP-II anomaly. The size of the cochleae in both anomalies showed no significant difference from

  13. Explicit Constructions and Bounds for Batch Codes with Restricted Size of Reconstruction Sets

    OpenAIRE

    Thomas, Eldho K.; Skachek, Vitaly

    2017-01-01

    Linear batch codes and codes for private information retrieval (PIR) with a query size $t$ and a restricted size $r$ of the reconstruction sets are studied. New bounds on the parameters of such codes are derived for small values of $t$ or of $r$ by providing corresponding constructions. By building on the ideas of Cadambe and Mazumdar, a new bound in a recursive form is derived for batch codes and PIR codes.

  14. Impact of sample size on principal component analysis ordination of an environmental data set: effects on eigenstructure

    Directory of Open Access Journals (Sweden)

    Shaukat S. Shahid

    2016-06-01

    Full Text Available In this study, we used bootstrap simulation of a real data set to investigate the impact of sample size (N = 20, 30, 40 and 50 on the eigenvalues and eigenvectors resulting from principal component analysis (PCA. For each sample size, 100 bootstrap samples were drawn from environmental data matrix pertaining to water quality variables (p = 22 of a small data set comprising of 55 samples (stations from where water samples were collected. Because in ecology and environmental sciences the data sets are invariably small owing to high cost of collection and analysis of samples, we restricted our study to relatively small sample sizes. We focused attention on comparison of first 6 eigenvectors and first 10 eigenvalues. Data sets were compared using agglomerative cluster analysis using Ward’s method that does not require any stringent distributional assumptions.

  15. ADME evaluation in drug discovery. 1. Applications of genetic algorithms to the prediction of blood-brain partitioning of a large set of drugs.

    Science.gov (United States)

    Hou, Tingjun; Xu, Xiaojie

    2002-12-01

    In this study, the relationships between the brain-blood concentration ratio of 96 structurally diverse compounds with a large number of structurally derived descriptors were investigated. The linear models were based on molecular descriptors that can be calculated for any compound simply from a knowledge of its molecular structure. The linear correlation coefficients of the models were optimized by genetic algorithms (GAs), and the descriptors used in the linear models were automatically selected from 27 structurally derived descriptors. The GA optimizations resulted in a group of linear models with three or four molecular descriptors with good statistical significance. The change of descriptor use as the evolution proceeds demonstrates that the octane/water partition coefficient and the partial negative solvent-accessible surface area multiplied by the negative charge are crucial to brain-blood barrier permeability. Moreover, we found that the predictions using multiple QSPR models from GA optimization gave quite good results in spite of the diversity of structures, which was better than the predictions using the best single model. The predictions for the two external sets with 37 diverse compounds using multiple QSPR models indicate that the best linear models with four descriptors are sufficiently effective for predictive use. Considering the ease of computation of the descriptors, the linear models may be used as general utilities to screen the blood-brain barrier partitioning of drugs in a high-throughput fashion.

  16. Partitioning sparse rectangular matrices for parallel processing

    Energy Technology Data Exchange (ETDEWEB)

    Kolda, T.G.

    1998-05-01

    The authors are interested in partitioning sparse rectangular matrices for parallel processing. The partitioning problem has been well-studied in the square symmetric case, but the rectangular problem has received very little attention. They will formalize the rectangular matrix partitioning problem and discuss several methods for solving it. They will extend the spectral partitioning method for symmetric matrices to the rectangular case and compare this method to three new methods -- the alternating partitioning method and two hybrid methods. The hybrid methods will be shown to be best.

  17. A brief history of partitions of numbers, partition functions and their modern applications

    Science.gov (United States)

    Debnath, Lokenath

    2016-04-01

    'Number rules the universe.' The Pythagoras 'If you wish to forsee the future of mathematics our course is to study the history and present conditions of the science.' Henri Poincaré 'The primary source (Urqell) of all mathematics are integers.' Hermann Minkowski This paper is written to commemorate the centennial anniversary of the Mathematical Association of America. It deals with a short history of different kinds of natural numbers including triangular, square, pentagonal, hexagonal and k-gonal numbers, and their simple properties and their geometrical representations. Included are Euclid's and Pythagorean's main contributions to elementary number theory with the main contents of the Euclid Elements of the 13-volume masterpiece of mathematical work. This is followed by Euler's new discovery of the additive number theory based on partitions of numbers. Special attention is given to many examples, Euler's theorems on partitions of numbers with geometrical representations of Ferrers' graphs, Young's diagrams, Lagrange's four-square theorem and the celebrated Waring problem. Included are Euler's generating functions for the partitions of numbers, Euler's pentagonal number theorem, Gauss' triangular and square number theorems and the Jacobi triple product identity. Applications of the theory of partitions of numbers to different statistics such as the Bose- Einstein, Fermi- Dirac, Gentile, and Maxwell- Boltzmann statistics are briefly discussed. Special attention is given to pedagogical information through historical approach to number theory so that students and teachers at the school, college and university levels can become familiar with the basic concepts of partitions of numbers, partition functions and their modern applications, and can pursue advanced study and research in analytical and computational number theory.

  18. A Comparison of Heuristics with Modularity Maximization Objective using Biological Data Sets

    Directory of Open Access Journals (Sweden)

    Pirim Harun

    2016-01-01

    Full Text Available Finding groups of objects exhibiting similar patterns is an important data analytics task. Many disciplines have their own terminologies such as cluster, group, clique, community etc. defining the similar objects in a set. Adopting the term community, many exact and heuristic algorithms are developed to find the communities of interest in available data sets. Here, three heuristic algorithms to find communities are compared using five gene expression data sets. The heuristics have a common objective function of maximizing the modularity that is a quality measure of a partition and a reflection of objects’ relevance in communities. Partitions generated by the heuristics are compared with the real ones using the adjusted rand index, one of the most commonly used external validation measures. The paper discusses the results of the partitions on the mentioned biological data sets.

  19. Molecular Descriptors Family on Structure Activity Relationships 6. Octanol-Water Partition Coefficient of Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    Lorentz JÄNTSCHI

    2006-01-01

    Full Text Available Octanol-water partition coefficient of two hundred and six polychlorinated biphenyls was model by the use of an original method based on complex information obtained from compounds structure. The regression analysis shows that best results are obtained in four-varied model (r2 = 0.9168. The prediction ability of the model was studied through leave-one-out analysis (r2cv(loo = 0.9093 and in training and test sets analysis. Modeling the octanol-water partition coefficient of polychlorinated biphenyls by integration of complex structural information provide a stable and performing four-varied model, allowing us to make remarks about relationship between structure of polychlorinated biphenyls and associated octanol-water partition coefficients.

  20. A Theoretical Study of the Separation Principle in Size Exclusion Chromatography

    DEFF Research Database (Denmark)

    Wang, Yanwei; Teraoka, Iwao; Hansen, Flemming Yssing

    2010-01-01

    as a function of the retention volume, results for both linear and branched polyethylene molecules lie nearly on the master curve determined by linear polystyrene standards. Our findings support the equilibrium thermodynamic separation principle in SEC. Since the mean span dimension is a purely geometric size......The principle of polymer separation in size exclusion chromatography (SEC) is studied based on a classical equilibrium partitioning theory. The task is to examine the correlation between the mean span dimension of polymer chains and their equilibrium partition coefficients with confining pores...

  1. Consolidated Incineration Facility metals partitioning test

    International Nuclear Information System (INIS)

    Burns, D.B.

    1993-01-01

    Test burns were conducted at Energy and Environmental Research Corporation's rotary kiln simulator, the Solid Waste Incineration Test Facility, using surrogate CIF wastes spiked with hazardous metals and organics. The primary objective for this test program was measuring heavy metals partition between the kiln bottom ash, scrubber blowdown solution, and incinerator stack gas. Also, these secondary waste streams were characterized to determine waste treatment requirements prior to final disposal. These tests were designed to investigate the effect of several parameters on metals partitioning: incineration temperature; waste chloride concentration; waste form (solid or liquid); and chloride concentration in the scrubber water. Tests were conducted at three kiln operating temperatures. Three waste simulants were burned, two solid waste mixtures (paper, plastic, latex, and one with and one without PVC), and a liquid waste mixture (containing benzene and chlorobenzene). Toxic organic and metal compounds were spiked into the simulated wastes to evaluate their fate under various combustion conditions. Kiln offgases were sampled for volatile organic compounds (VOC), semi-volatile organic compounds (SVOC), polychlorinated dibenz[p]dioxins and polychlorinated dibenzofurans (PCDD/PCDF), metals, particulate loading and size distribution, HCl, and combustion products. Stack gas sampling was performed to determine additional treatment requirements prior to final waste disposal. Significant test results are summarized below

  2. Development of partitioning method : cold experiment with partitioning test facility in NUCEF (I)

    International Nuclear Information System (INIS)

    Yamaguchi, Isoo; Morita, Yasuji; Kondo, Yasuo

    1996-03-01

    A test facility in which about 1.85 x 10 14 Bq of high-level liquid waste can be treated has been completed in 1994 at Nuclear Fuel Cycle Safety Engineering Research Facility (NUCEF) for research and development of Partitioning Method. The outline of the partitioning test facility and support equipments for it which were design terms, constructions, arrangements, functions and inspections were given in JAERI-Tech 94-030. The present report describes the results of the water transfer test and partitioning tests, which are methods of precipitation by denitration, oxalate precipitation, solvent extraction, and adsorption with inorganic ion exchanger, using nitric acid to master operation method of the test facility. As often as issues related to equipments occurred during the tests, they were improved. As to issues related to processes such as being stopped up of columns, their measures of solution were found by testing in laboratories. They were reflected in operation of the Partitioning Test Facility. Their particulars and improving points were described in this report. (author)

  3. Purification of biomaterials by phase partitioning

    Science.gov (United States)

    Harris, J. M.

    1984-01-01

    A technique which is particularly suited to microgravity environments and which is potentially more powerful than electrophoresis is phase partitioning. Phase partitioning is purification by partitioning between the two immiscible aqueous layers formed by solution of the polymers poly(ethylene glycol) and dextran in water. This technique proved to be very useful for separations in one-g but is limited for cells because the cells are more dense than the phase solutions thus tend to sediment to the bottom of the container before reaching equilibrium with the preferred phase. There are three phases to work in this area: synthesis of new polymers for affinity phase partitioning; development of automated apparatus for ground-based separations; and design of apparatus for performing simple phase partitioning space experiments, including examination of mechanisms for separating phases in the absence of gravity.

  4. Betweenness-based algorithm for a partition scale-free graph

    International Nuclear Information System (INIS)

    Zhang Bai-Da; Wu Jun-Jie; Zhou Jing; Tang Yu-Hua

    2011-01-01

    Many real-world networks are found to be scale-free. However, graph partition technology, as a technology capable of parallel computing, performs poorly when scale-free graphs are provided. The reason for this is that traditional partitioning algorithms are designed for random networks and regular networks, rather than for scale-free networks. Multilevel graph-partitioning algorithms are currently considered to be the state of the art and are used extensively. In this paper, we analyse the reasons why traditional multilevel graph-partitioning algorithms perform poorly and present a new multilevel graph-partitioning paradigm, top down partitioning, which derives its name from the comparison with the traditional bottom—up partitioning. A new multilevel partitioning algorithm, named betweenness-based partitioning algorithm, is also presented as an implementation of top—down partitioning paradigm. An experimental evaluation of seven different real-world scale-free networks shows that the betweenness-based partitioning algorithm significantly outperforms the existing state-of-the-art approaches. (interdisciplinary physics and related areas of science and technology)

  5. Toxicologically important trace elements and organic compounds investigated in size-fractionated urban particulate matter collected near the Prague highway

    Czech Academy of Sciences Publication Activity Database

    Sysalová, J.; Sýkorová, Ivana; Havelcová, Martina; Száková, J.; Trejtnarová, Hana; Kotlík, B.

    2012-01-01

    Roč. 437, October (2012), s. 127-136 ISSN 0048-9697 R&D Projects: GA ČR GA205/09/1162 Institutional support: RVO:67985891 Keywords : urban particulate matter * grain- size partitioning * grain- size partitioning Subject RIV: DI - Air Pollution ; Quality Impact factor: 3.258, year: 2012

  6. Gas-particle partitioning of semivolatile organic compounds (SOCs) on mixtures of aerosols in a smog chamber.

    Science.gov (United States)

    Chandramouli, Bharadwaj; Jang, Myoseon; Kamens, Richard M

    2003-09-15

    The partitioning behavior of a set of diverse SOCs on two and three component mixtures of aerosols from different sources was studied using smog chamber experimental data. A set of SOCs of different compound types was introduced into a system containing a mixture of aerosols from two or more sources. Gas and particle samples were taken using a filter-filter-denuder sampling system, and a partitioning coefficient Kp was estimated using Kp = Cp/(CgTSP). Particle size distributions were measured using a differential mobility analyzer and a light scattering detector. Gas and particle samples were analyzed using GCMS. The aerosol composition in the chamber was tracked chemically using a combination of signature compounds and the organic matter mass fraction (f(om)) of the individual aerosol sources. The physical nature of the aerosol mixture in the chamber was determined using particle size distributions, and an aggregate Kp was estimated from theoretically calculated Kp on the individual sources. Model fits for Kp showed that when the mixture involved primary sources of aerosol, the aggregate Kp of the mixture could be successfully modeled as an external mixture of the Kp on the individual aerosols. There were significant differences observed for some SOCs between modeling the system as an external and as an internal mixture. However, when one of the aerosol sources was secondary, the aggregate model Kp required incorporation of the secondary aerosol products on the preexisting aerosol for adequate model fits. Modeling such a system as an external mixture grossly overpredicted the Kp of alkanes in the mixture. Indirect evidence of heterogeneous, acid-catalyzed reactions in the particle phase was also seen, leading to a significant increase in the polarity of the resulting aerosol mix and a resulting decrease in the observed Kp of alkanes in the chamber. The model was partly consistent with this decrease but could not completely explain the reduction in Kp because of

  7. Plane partition vesicles

    International Nuclear Information System (INIS)

    Rensburg, E J Janse van; Ma, J

    2006-01-01

    We examine partitions and their natural three-dimensional generalizations, plane partitions, as models of vesicles undergoing an inflation-deflation transition. The phase diagrams of these models include a critical point corresponding to an inflation-deflation transition, and exhibits multicritical scaling in the vicinity of a multicritical point located elsewhere on the critical curve. We determine the locations of the multicritical points by analysing the generating functions using analytic and numerical means. In addition, we determine the numerical values of the multicritical scaling exponents associated with the multicritical scaling regimes in these models

  8. The importance of applying an appropriate data partitioning

    CERN Document Server

    Dimitrov, Gancho; The ATLAS collaboration

    2015-01-01

    In this presentation are described specific technical solutions put in place in various database applications of the ATLAS experiment at LHC where we make use of several partitioning techniques available in Oracle 11g. With the broadly used range partitioning and its option of automatic interval partitioning we add our own logic in PLSQL procedures and scheduler jobs to sustain data sliding windows in order to enforce various data retention policies. We also make use of the new Oracle 11g reference partitioning in the ATLAS Nightly Build System to achieve uniform data segmentation. However the most challenging was to segment the data of the new ATLAS Distributed Data Management system, which resulted in tens of thousands list type partitions and sub-partitions. Partition and sub-partition management, index strategy, statistics gathering and queries execution plan stability are important factors when choosing an appropriate physical model for the application data management. The so-far accumulated knowledge wi...

  9. Word length, set size, and lexical factors: Re-examining what causes the word length effect.

    Science.gov (United States)

    Guitard, Dominic; Gabel, Andrew J; Saint-Aubin, Jean; Surprenant, Aimée M; Neath, Ian

    2018-04-19

    The word length effect, better recall of lists of short (fewer syllables) than long (more syllables) words has been termed a benchmark effect of working memory. Despite this, experiments on the word length effect can yield quite different results depending on set size and stimulus properties. Seven experiments are reported that address these 2 issues. Experiment 1 replicated the finding of a preserved word length effect under concurrent articulation for large stimulus sets, which contrasts with the abolition of the word length effect by concurrent articulation for small stimulus sets. Experiment 2, however, demonstrated that when the short and long words are equated on more dimensions, concurrent articulation abolishes the word length effect for large stimulus sets. Experiment 3 shows a standard word length effect when output time is equated, but Experiments 4-6 show no word length effect when short and long words are equated on increasingly more dimensions that previous demonstrations have overlooked. Finally, Experiment 7 compared recall of a small and large neighborhood words that were equated on all the dimensions used in Experiment 6 (except for those directly related to neighborhood size) and a neighborhood size effect was still observed. We conclude that lexical factors, rather than word length per se, are better predictors of when the word length effect will occur. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  10. Set discrimination of quantum states

    International Nuclear Information System (INIS)

    Zhang Shengyu; Ying Mingsheng

    2002-01-01

    We introduce a notion of set discrimination, which is an interesting extension of quantum state discrimination. A state is secretly chosen from a number of quantum states, which are partitioned into some disjoint sets. A set discrimination is required to identify which set the given state belongs to. Several essential problems are addressed in this paper, including the condition of perfect set discrimination, unambiguous set discrimination, and in the latter case, the efficiency of the discrimination. This generalizes some important results on quantum state discrimination in the literature. A combination of state and set discrimination and the efficiency are also studied

  11. Present status of partitioning developments

    International Nuclear Information System (INIS)

    Nakamura, Haruto; Kubota, Masumitsu; Tachimori, Shoichi

    1978-09-01

    Evolution and development of the concept of partitioning of high-level liquid wastes (HLLW) in nuclear fuel reprocessing are reviewed historically from the early phase of separating useful radioisotopes from HLLW to the recent phase of eliminating hazardous nuclides such as transuranium elements for safe waste disposal. Since the criteria in determining the nuclides for elimination and the respective decontamination factors are important in the strategy of partitioning, current views on the criteria are summarized. As elimination of the transuranium is most significant in the partitioning, various methods available of separating them from fission products are evaluated. (auth.)

  12. Fast Graph Partitioning Active Contours for Image Segmentation Using Histograms

    Directory of Open Access Journals (Sweden)

    Nath SumitK

    2009-01-01

    Full Text Available Abstract We present a method to improve the accuracy and speed, as well as significantly reduce the memory requirements, for the recently proposed Graph Partitioning Active Contours (GPACs algorithm for image segmentation in the work of Sumengen and Manjunath (2006. Instead of computing an approximate but still expensive dissimilarity matrix of quadratic size, , for a 2D image of size and regular image tiles of size , we use fixed length histograms and an intensity-based symmetric-centrosymmetric extensor matrix to jointly compute terms associated with the complete dissimilarity matrix. This computationally efficient reformulation of GPAC using a very small memory footprint offers two distinct advantages over the original implementation. It speeds up convergence of the evolving active contour and seamlessly extends performance of GPAC to multidimensional images.

  13. Resource partitioning of sonar frequency bands in rhinolophoid bats.

    Science.gov (United States)

    Heller, Klaus-Gerhard; Helversen, Otto V

    1989-08-01

    In the Constant Frequency portions of the orientation calls of various Rhinolophus and Hipposideros species, the frequency with the strongest amplitude was studied comparatively. (1) In the five European species of the genus Rhinolophus call frequencies are either species-specific (R. ferrumequinum, R. blasii and R. euryale) or they overlap (R. hipposideros and R. mehelyi). The call frequency distributions are approximately 5-9 kHz wide, thus their ranges spead less than ±5% from the mean (Fig. 1). Frequency distributions are considerably narrower within smaller geographic areas. (2) As in other bat groups, call frequencies of the Rhinolophoidea are negatively correlated with body size (Fig. 3). Regression lines for the genera Rhinolophus and Rhinolophus, species from dryer climates have on the average higher call frequencies than species from tropical rain forests. (4) The Krau Game Reserve, a still largely intact rain forest area in Malaysia, harbours at least 12 syntopic Rhinolophus and Hipposiderso species. Their call frequencies lie between 40 and 200 kHz (Fig. 2). Distribution over the available frequency range is significantly more even than could be expected from chance alone. Two different null hypotheses to test for random character distribution were derived from frequency-size-relations and by sampling species assemblages from a species pool (Monte Carlo method); both were rejected. In particular, call frequencies lying close together are avoided (Figs. 4, 5). Conversely, the distribution of size ratios complied with a corresponding null hypothesis. This even distribution may be a consequence of resource partitioning with respect to prey type. Alternatively, the importance of these calls as social signals (e.g. recognition of conspecifics) might have necessitated a communication channel partitioning.

  14. Optimality Bounds for a Variational Relaxation of the Image Partitioning Problem

    KAUST Repository

    Lellmann, Jan

    2012-11-09

    We consider a variational convex relaxation of a class of optimal partitioning and multiclass labeling problems, which has recently proven quite successful and can be seen as a continuous analogue of Linear Programming (LP) relaxation methods for finite-dimensional problems. While for the latter several optimality bounds are known, to our knowledge no such bounds exist in the infinite-dimensional setting. We provide such a bound by analyzing a probabilistic rounding method, showing that it is possible to obtain an integral solution of the original partitioning problem from a solution of the relaxed problem with an a priori upper bound on the objective. The approach has a natural interpretation as an approximate, multiclass variant of the celebrated coarea formula. © 2012 Springer Science+Business Media New York.

  15. Implementation of a partitioned algorithm for simulation of large CSI problems

    Science.gov (United States)

    Alvin, Kenneth F.; Park, K. C.

    1991-01-01

    The implementation of a partitioned numerical algorithm for determining the dynamic response of coupled structure/controller/estimator finite-dimensional systems is reviewed. The partitioned approach leads to a set of coupled first and second-order linear differential equations which are numerically integrated with extrapolation and implicit step methods. The present software implementation, ACSIS, utilizes parallel processing techniques at various levels to optimize performance on a shared-memory concurrent/vector processing system. A general procedure for the design of controller and filter gains is also implemented, which utilizes the vibration characteristics of the structure to be solved. Also presented are: example problems; a user's guide to the software; the procedures and algorithm scripts; a stability analysis for the algorithm; and the source code for the parallel implementation.

  16. Comparison of Hounsfield units by changing in size of physical area and setting size of region of interest by using the CT phantom made with a 3D printer

    International Nuclear Information System (INIS)

    Seung, Youl Hun

    2015-01-01

    In this study, we have observed the change of the Hounsfield (HU) in the alteration of by changing in size of physical area and setting size of region of interest (ROI) at focus on kVp and mAs. Four-channel multi-detector computed tomography was used to get transverse axial scanning images and HU. Three dimensional printer which is type of fused deposition modeling (FDM) was used to produce the Phantom. The structure of the phantom was designed to be a type of cylinder that contains 33 mm, 24 mm, 19 mm, 16 mm, 9 mm size of circle holes that are symmetrically located. It was charged with mixing iodine contrast agent and distilled water in the holes. The images were gained with changing by 90 kVp, 120 kVp, 140 kVp and 50 mAs, 100 mAs, 150 mAs, respectively. The ‘image J’ was used to get the HU measurement of gained images of ROI. As a result, it was confirmed that kVp affects to HU more than mAs. And it is suggested that the smaller size of physical area, the more decreasing HU even in material of a uniform density and the smaller setting size of ROI, the more increasing HU. Therefore, it is reason that to set maximum ROI within 5 HU is the best way to minimize in the alteration of by changing in size of physical area and setting size of region of interest

  17. Comparison of Hounsfield units by changing in size of physical area and setting size of region of interest by using the CT phantom made with a 3D printer

    Energy Technology Data Exchange (ETDEWEB)

    Seung, Youl Hun [Dept. of Radiological Science, Cheongju University, Cheongju (Korea, Republic of)

    2015-12-15

    In this study, we have observed the change of the Hounsfield (HU) in the alteration of by changing in size of physical area and setting size of region of interest (ROI) at focus on kVp and mAs. Four-channel multi-detector computed tomography was used to get transverse axial scanning images and HU. Three dimensional printer which is type of fused deposition modeling (FDM) was used to produce the Phantom. The structure of the phantom was designed to be a type of cylinder that contains 33 mm, 24 mm, 19 mm, 16 mm, 9 mm size of circle holes that are symmetrically located. It was charged with mixing iodine contrast agent and distilled water in the holes. The images were gained with changing by 90 kVp, 120 kVp, 140 kVp and 50 mAs, 100 mAs, 150 mAs, respectively. The ‘image J’ was used to get the HU measurement of gained images of ROI. As a result, it was confirmed that kVp affects to HU more than mAs. And it is suggested that the smaller size of physical area, the more decreasing HU even in material of a uniform density and the smaller setting size of ROI, the more increasing HU. Therefore, it is reason that to set maximum ROI within 5 HU is the best way to minimize in the alteration of by changing in size of physical area and setting size of region of interest.

  18. Gentile statistics and restricted partitions

    Indian Academy of Sciences (India)

    The partition function of Gentile statistics also has the property that it nicely interpolates between the ... We now construct the partition function for such a system which also incorporates the property of interpolation ... As in [4], we however keep s arbitrary even though for s > 2 there are no quadratic. Hamiltonian systems.

  19. The importance of having an appropriate data segmentation (partitioning)

    CERN Document Server

    Dimitrov, Gancho; The ATLAS collaboration

    2014-01-01

    In this presentation will be shown real life examples from database applications in the ATLAS experiment @ LHC where we make use of many Oracle partitioning techniques available in Oracle 11g. With the broadly used range partitioning and its option of automatic interval partitioning we add our own logic in PLSQL for sustaining data sliding windows in order to enforce various data retention policies. We also make use of the reference partitioning in some use cases, however the most challenging was to segment the data of a large bookkeeping system which resulted in tens of thousands list partitions and list sub-partitions. Partition and sub-partition management, index strategy, statistics gathering and queries execution plan stability are important factors when choosing an appropriate for the use case data management model. The gained experience with all of those will be shared with the audience.

  20. A detailed aerosol mixing state model for investigating interactions between mixing state, semivolatile partitioning, and coagulation

    Directory of Open Access Journals (Sweden)

    J. Lu

    2010-04-01

    Full Text Available A new method for describing externally mixed particles, the Detailed Aerosol Mixing State (DAMS representation, is presented in this study. This novel method classifies aerosols by both composition and size, using a user-specified mixing criterion to define boundaries between compositional populations. Interactions between aerosol mixing state, semivolatile partitioning, and coagulation are investigated with a Lagrangian box model that incorporates the DAMS approach. Model results predict that mixing state affects the amount and types of semivolatile organics that partition to available aerosol phases, causing external mixtures to produce a more size-varying composition than internal mixtures. Both coagulation and condensation contribute to the mixing of emitted particles, producing a collection of multiple compositionally distinct aerosol populations that exists somewhere between the extremes of a strictly external or internal mixture. The selection of mixing criteria has a significant impact on the size and type of individual populations that compose the modeled aerosol mixture. Computational demands for external mixture modeling are significant and can be controlled by limiting the number of aerosol populations used in the model.

  1. Generating Milton Babbitt's all-partition arrays

    OpenAIRE

    Bemman, Brian; Meredith, David

    2016-01-01

    In most of Milton Babbitt's (1916–2011) works written since the early 1960s, both the pitch and rhythmic content is organized according to a highly constrained structure known as the all-partition array. The all-partition array provides a framework that ensures that as many different forms of a tone row as possible (generated by any combination of transposition, inversion or reversal) are expressed 'horizontally' and that each integer partition of 12 whose cardinality is no greater than the n...

  2. Comparison of modeling approaches for carbon partitioning: Impact on estimates of global net primary production and equilibrium biomass of woody vegetation from MODIS GPP

    Science.gov (United States)

    Ise, Takeshi; Litton, Creighton M.; Giardina, Christian P.; Ito, Akihiko

    2010-12-01

    Partitioning of gross primary production (GPP) to aboveground versus belowground, to growth versus respiration, and to short versus long-lived tissues exerts a strong influence on ecosystem structure and function, with potentially large implications for the global carbon budget. A recent meta-analysis of forest ecosystems suggests that carbon partitioning to leaves, stems, and roots varies consistently with GPP and that the ratio of net primary production (NPP) to GPP is conservative across environmental gradients. To examine influences of carbon partitioning schemes employed by global ecosystem models, we used this meta-analysis-based model and a satellite-based (MODIS) terrestrial GPP data set to estimate global woody NPP and equilibrium biomass, and then compared it to two process-based ecosystem models (Biome-BGC and VISIT) using the same GPP data set. We hypothesized that different carbon partitioning schemes would result in large differences in global estimates of woody NPP and equilibrium biomass. Woody NPP estimated by Biome-BGC and VISIT was 25% and 29% higher than the meta-analysis-based model for boreal forests, with smaller differences in temperate and tropics. Global equilibrium woody biomass, calculated from model-specific NPP estimates and a single set of tissue turnover rates, was 48 and 226 Pg C higher for Biome-BGC and VISIT compared to the meta-analysis-based model, reflecting differences in carbon partitioning to structural versus metabolically active tissues. In summary, we found that different carbon partitioning schemes resulted in large variations in estimates of global woody carbon flux and storage, indicating that stand-level controls on carbon partitioning are not yet accurately represented in ecosystem models.

  3. Heavy metal partitioning of suspended particulate matter-water and sediment-water in the Yangtze Estuary.

    Science.gov (United States)

    Feng, Chenghong; Guo, Xiaoyu; Yin, Su; Tian, Chenhao; Li, Yangyang; Shen, Zhenyao

    2017-10-01

    The partitioning of ten heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, and Zn) between the water, suspended particulate matter (SPM), and sediments in seven channel sections during three hydrologic seasons in the Yangtze Estuary was comprehensively investigated. Special attention was paid to the role of tides, influential factors (concentrations of SPM and dissolved organic carbon, and particle size), and heavy metal speciation. The SPM-water and sediment-water partition coefficients (K p ) of the heavy metals exhibited similar changes along the channel sections, though the former were larger throughout the estuary. Because of the higher salinity, the K p values of most of the metals were higher in the north branch than in the south branch. The K p values of Cd, Co, and As generally decreased from the wet season to the dry season. Both the diagonal line method and paired samples t-test showed that no specific phase transfer of heavy metals existed during the flood and ebb tides, but the sediment-water K p was more concentrated for the diagonal line method, owing to the relatively smaller tidal influences on the sediment. The partition coefficients (especially the K p for SPM-water) had negative correlations with the dissolved organic carbon (DOC) but positive correlations were noted with the particle size for most of the heavy metals in sediment. Two types of significant correlations were observed between K p and metal speciation (i.e., exchangeable, carbonate, reducible, organic, and residual fractions), which can be used to identify the dominant phase-partition mechanisms (e.g., adsorption or desorption) of heavy metals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. A partition enhanced mining algorithm for distributed association rule mining systems

    Directory of Open Access Journals (Sweden)

    A.O. Ogunde

    2015-11-01

    Full Text Available The extraction of patterns and rules from large distributed databases through existing Distributed Association Rule Mining (DARM systems is still faced with enormous challenges such as high response times, high communication costs and inability to adapt to the constantly changing databases. In this work, a Partition Enhanced Mining Algorithm (PEMA is presented to address these problems. In PEMA, the Association Rule Mining Coordinating Agent receives a request and decides the appropriate data sites, partitioning strategy and mining agents to use. The mining process is divided into two stages. In the first stage, the data agents horizontally segment the databases with small average transaction length into relatively smaller partitions based on the number of available sites and the available memory. On the other hand, databases with relatively large average transaction length were vertically partitioned. After this, Mobile Agent-Based Association Rule Mining-Agents, which are the mining agents, carry out the discovery of the local frequent itemsets. At the second stage, the local frequent itemsets were incrementally integrated by the from one data site to another to get the global frequent itemsets. This reduced the response time and communication cost in the system. Results from experiments conducted on real datasets showed that the average response time of PEMA showed an improvement over existing algorithms. Similarly, PEMA incurred lower communication costs with average size of messages exchanged lower when compared with benchmark DARM systems. This result showed that PEMA could be efficiently deployed for efficient discovery of valuable knowledge in distributed databases.

  5. Data Partitioning Technique for Improved Video Prioritization

    Directory of Open Access Journals (Sweden)

    Ismail Amin Ali

    2017-07-01

    Full Text Available A compressed video bitstream can be partitioned according to the coding priority of the data, allowing prioritized wireless communication or selective dropping in a congested channel. Known as data partitioning in the H.264/Advanced Video Coding (AVC codec, this paper introduces a further sub-partition of one of the H.264/AVC codec’s three data-partitions. Results show a 5 dB improvement in Peak Signal-to-Noise Ratio (PSNR through this innovation. In particular, the data partition containing intra-coded residuals is sub-divided into data from: those macroblocks (MBs naturally intra-coded, and those MBs forcibly inserted for non-periodic intra-refresh. Interactive user-to-user video streaming can benefit, as then HTTP adaptive streaming is inappropriate and the High Efficiency Video Coding (HEVC codec is too energy demanding.

  6. Partitioning behaviour of natural radionuclides during combustion of coal in thermal power plants

    International Nuclear Information System (INIS)

    Sahu, S.K.; Tiwari, M.; Bhangare, R.C.; Ajmal, P.Y.; Pandit, G.G.

    2014-01-01

    All fossil fuels contain low levels of naturally occurring radioactive substances. The environmental impact of radionuclide-containing waste products from coal combustion is an important issue. These radionuclides vaporize in the hot portions of the coal combustor and then return to the solid phase in cooler downstream zones. Indian coal used in power plants generally has high ash yield (35-45%) and is of low quality. In the burning process of coal, minerals undergo thermal decomposition, fusion, disintegration, and agglomeration. A major portion of elements in the boiler enter into slag or bottom ash, and the rest of the inorganic materials find their way into the flue gas, in fly ash or vapor. Fly and bottom ash are significant sources of exposure to these radionuclides. In the present study, coal and ash samples collected from six thermal power stations were analyzed to determine their natural radioactivity content and the partitioning behavior of these radionuclides was carried out by tracing their activities in fly and bottom ashes. The partitioning of radionuclides is strongly dependent on the size of associated ash particle. Polonium-210 was mostly associated with the finest fraction and showed large variation with particle size whereas 232 Th showed least dependence on the particle size. The high activities of all radionuclides in fly ashes than that of bottom ashes thus may be due to strong affinity of the nuclides towards the finer particle fractions. All the radionuclide distribution favored small particle sizes

  7. EXTENSION OF FORMULAS FOR PARTITION FUNCTIONS

    African Journals Online (AJOL)

    Ladan et al.

    2Department of Mathematics, Ahmadu Bello University, Zaria. ... 2 + 1 + 1. = 1 + 1 + 1 + 1. Partition function ( ). Andrew and Erikson (2004) stated that the ..... Andrews, G.E., 1984, The Theory of Partitions, Cambridge ... Pure Appl. Math.

  8. A physically based catchment partitioning method for hydrological analysis

    Science.gov (United States)

    Menduni, Giovanni; Riboni, Vittoria

    2000-07-01

    We propose a partitioning method for the topographic surface, which is particularly suitable for hydrological distributed modelling and shallow-landslide distributed modelling. The model provides variable mesh size and appears to be a natural evolution of contour-based digital terrain models. The proposed method allows the drainage network to be derived from the contour lines. The single channels are calculated via a search for the steepest downslope lines. Then, for each network node, the contributing area is determined by means of a search for both steepest upslope and downslope lines. This leads to the basin being partitioned into physically based finite elements delimited by irregular polygons. In particular, the distributed computation of local geomorphological parameters (i.e. aspect, average slope and elevation, main stream length, concentration time, etc.) can be performed easily for each single element. The contributing area system, together with the information on the distribution of geomorphological parameters provide a useful tool for distributed hydrological modelling and simulation of environmental processes such as erosion, sediment transport and shallow landslides.

  9. Quantum Dilogarithms and Partition q-Series

    Science.gov (United States)

    Kato, Akishi; Terashima, Yuji

    2015-08-01

    In our previous work (Kato and Terashima, Commun Math Phys. arXiv:1403.6569, 2014), we introduced the partition q-series for mutation loop γ—a loop in exchange quiver. In this paper, we show that for a certain class of mutation sequences, called reddening sequences, the graded version of partition q-series essentially coincides with the ordered product of quantum dilogarithm associated with each mutation; the partition q-series provides a state-sum description of combinatorial Donaldson-Thomas invariants introduced by Keller.

  10. On structure-property relationship in nanostructured bainitic steel subjected to the quenching and partitioning process

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Ping [Material Science & Engineering Research Center, School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Gao, Guhui, E-mail: gaogh@bjtu.edu.cn [Material Science & Engineering Research Center, School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Zhang, Han [Max-Planck-Institut für Eisenforschung, Max-Planck-Str. 1, 40237 Düsseldorf (Germany); Tan, Zhunli [Material Science & Engineering Research Center, School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Misra, R.DK. [Laboratory for Excellence in Advanced Steel Research, Department of Metallurgical, Materials and Biomedical Engineering, University of Texas at El Paso, TX 79968-0520 (United States); Bai, Bingzhe [Material Science & Engineering Research Center, School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Tsinghua University, Key Laboratory of Advanced Material, School of Material Science and Engineering, Beijing 100084 (China)

    2016-04-20

    We elucidate here the mechanistic contribution of the application of quenching and partitioning (Q&P) concept to a high carbon Mn-Si-Cr steel in obtaining a multiphase microstructure comprising of martensite/austenite and nanostructured bainite (bainitic ferrite and nanometer-sized film-like retained austenite) that exhibited tensile strength of 1923 MPa and total elongation of 18.3%. The excellent mechanical properties are attributed to the enhanced refinement of blocky austenite islands obtained by the Q&P process. The austenite was stabilized by both carbon partitioning from martensite and bainite transformation. Compared with conventional heat treatment to produce nanostructured bainite, the total time is significantly reduced without degradation of mechanical properties.

  11. Distributed Sleep Scheduling in Wireless Sensor Networks via Fractional Domatic Partitioning

    Science.gov (United States)

    Schumacher, André; Haanpää, Harri

    We consider setting up sleep scheduling in sensor networks. We formulate the problem as an instance of the fractional domatic partition problem and obtain a distributed approximation algorithm by applying linear programming approximation techniques. Our algorithm is an application of the Garg-Könemann (GK) scheme that requires solving an instance of the minimum weight dominating set (MWDS) problem as a subroutine. Our two main contributions are a distributed implementation of the GK scheme for the sleep-scheduling problem and a novel asynchronous distributed algorithm for approximating MWDS based on a primal-dual analysis of Chvátal's set-cover algorithm. We evaluate our algorithm with ns2 simulations.

  12. A statistical mechanical approach to restricted integer partition functions

    Science.gov (United States)

    Zhou, Chi-Chun; Dai, Wu-Sheng

    2018-05-01

    The main aim of this paper is twofold: (1) suggesting a statistical mechanical approach to the calculation of the generating function of restricted integer partition functions which count the number of partitions—a way of writing an integer as a sum of other integers under certain restrictions. In this approach, the generating function of restricted integer partition functions is constructed from the canonical partition functions of various quantum gases. (2) Introducing a new type of restricted integer partition functions corresponding to general statistics which is a generalization of Gentile statistics in statistical mechanics; many kinds of restricted integer partition functions are special cases of this restricted integer partition function. Moreover, with statistical mechanics as a bridge, we reveal a mathematical fact: the generating function of restricted integer partition function is just the symmetric function which is a class of functions being invariant under the action of permutation groups. Using this approach, we provide some expressions of restricted integer partition functions as examples.

  13. Spatially Partitioned Embedded Runge--Kutta Methods

    KAUST Repository

    Ketcheson, David I.

    2013-10-30

    We study spatially partitioned embedded Runge--Kutta (SPERK) schemes for partial differential equations (PDEs), in which each of the component schemes is applied over a different part of the spatial domain. Such methods may be convenient for problems in which the smoothness of the solution or the magnitudes of the PDE coefficients vary strongly in space. We focus on embedded partitioned methods as they offer greater efficiency and avoid the order reduction that may occur in nonembedded schemes. We demonstrate that the lack of conservation in partitioned schemes can lead to nonphysical effects and propose conservative additive schemes based on partitioning the fluxes rather than the ordinary differential equations. A variety of SPERK schemes are presented, including an embedded pair suitable for the time evolution of fifth-order weighted nonoscillatory spatial discretizations. Numerical experiments are provided to support the theory.

  14. Spatially Partitioned Embedded Runge--Kutta Methods

    KAUST Repository

    Ketcheson, David I.; MacDonald, Colin B.; Ruuth, Steven J.

    2013-01-01

    We study spatially partitioned embedded Runge--Kutta (SPERK) schemes for partial differential equations (PDEs), in which each of the component schemes is applied over a different part of the spatial domain. Such methods may be convenient for problems in which the smoothness of the solution or the magnitudes of the PDE coefficients vary strongly in space. We focus on embedded partitioned methods as they offer greater efficiency and avoid the order reduction that may occur in nonembedded schemes. We demonstrate that the lack of conservation in partitioned schemes can lead to nonphysical effects and propose conservative additive schemes based on partitioning the fluxes rather than the ordinary differential equations. A variety of SPERK schemes are presented, including an embedded pair suitable for the time evolution of fifth-order weighted nonoscillatory spatial discretizations. Numerical experiments are provided to support the theory.

  15. Partial Key Grouping: Load-Balanced Partitioning of Distributed Streams

    OpenAIRE

    Nasir, Muhammad Anis Uddin; Morales, Gianmarco De Francisci; Garcia-Soriano, David; Kourtellis, Nicolas; Serafini, Marco

    2015-01-01

    We study the problem of load balancing in distributed stream processing engines, which is exacerbated in the presence of skew. We introduce PARTIAL KEY GROUPING (PKG), a new stream partitioning scheme that adapts the classical “power of two choices” to a distributed streaming setting by leveraging two novel techniques: key splitting and local load estimation. In so doing, it achieves better load balancing than key grouping while being more scalable than shuffle grouping. We test PKG on severa...

  16. Partitioning of a scaled shallow-buried near-field blast load

    CSIR Research Space (South Africa)

    Reinecke, J David

    2015-07-01

    Full Text Available and target force response to a shallow and deep buried blast loads and the initial loading phase contribution to the blast load were quantified. There is no separate precursor air shock for shallow buried blast load and the initial loading phase impulse... stream_source_info Reinecke_2015.pdf.txt stream_content_type text/plain stream_size 24459 Content-Encoding UTF-8 stream_name Reinecke_2015.pdf.txt Content-Type text/plain; charset=UTF-8 Partitioning of a Scaled Shallow...

  17. Gas-particle partitioning of semi-volatile organics on organic aerosols using a predictive activity coefficient model: analysis of the effects of parameter choices on model performance

    Science.gov (United States)

    Chandramouli, Bharadwaj; Jang, Myoseon; Kamens, Richard M.

    The partitioning of a diverse set of semivolatile organic compounds (SOCs) on a variety of organic aerosols was studied using smog chamber experimental data. Existing data on the partitioning of SOCs on aerosols from wood combustion, diesel combustion, and the α-pinene-O 3 reaction was augmented by carrying out smog chamber partitioning experiments on aerosols from meat cooking, and catalyzed and uncatalyzed gasoline engine exhaust. Model compositions for aerosols from meat cooking and gasoline combustion emissions were used to calculate activity coefficients for the SOCs in the organic aerosols and the Pankow absorptive gas/particle partitioning model was used to calculate the partitioning coefficient Kp and quantitate the predictive improvements of using the activity coefficient. The slope of the log K p vs. log p L0 correlation for partitioning on aerosols from meat cooking improved from -0.81 to -0.94 after incorporation of activity coefficients iγ om. A stepwise regression analysis of the partitioning model revealed that for the data set used in this study, partitioning predictions on α-pinene-O 3 secondary aerosol and wood combustion aerosol showed statistically significant improvement after incorporation of iγ om, which can be attributed to their overall polarity. The partitioning model was sensitive to changes in aerosol composition when updated compositions for α-pinene-O 3 aerosol and wood combustion aerosol were used. The octanol-air partitioning coefficient's ( KOA) effectiveness as a partitioning correlator over a variety of aerosol types was evaluated. The slope of the log K p- log K OA correlation was not constant over the aerosol types and SOCs used in the study and the use of KOA for partitioning correlations can potentially lead to significant deviations, especially for polar aerosols.

  18. Multiaxial creep-fatigue life analysis using strainrange partitioning

    International Nuclear Information System (INIS)

    Manson, S.S.; Halford, G.R.

    1976-01-01

    Strain-Range Partitioning is a recently developed method for treating creep-fatigue interaction at elevated temperature. Most of the work to date has been on uniaxially loaded specimens, whereas practical applications often involve load multiaxiality. This paper shows how the method can be extended to treat multiaxiality through a set of rules for combining the strain components in the three principal directions. Closed hysteresis loops, as well as plastic and creep strain ratcheting, are included. An application to hold-time tests in torsion is used to illustrate the approach

  19. Dynamics of vacuum-sealed, double-leaf partitions

    Science.gov (United States)

    Kavanaugh, Joshua Stephen

    The goal of this research is to investigate the feasibility and potential effectiveness of using vacuum-sealed, double-leaf partitions for applications in noise control. Substantial work has been done previously on double-leaf partitions where the acoustics of the inner chamber and mechanical vibrations of structural supports are passively and actively controlled. The work presented here is unique in that the proposed system aims to eliminate the need for active acoustic control of transmitted acoustic energy by removing all the air between the two panels of the double partition. Therefore, the only remaining energy paths would be along the boundary and at the points where there are intermediate structural supports connecting the two panels. The eventual goal of the research is to develop a high-loss double-leaf partition that simplifies active control by removing the need for control of the air cavity and channeling all the energy into discrete structural paths. The work presented here is a first step towards the goal of designing a high-loss, actively-controlled double-leaf partition with an air-evacuated inner chamber. One experiment is conducted to investigate the effects of various levels of vacuum on the response of a double-leaf partition whose panels are mechanically coupled only at the boundary. Another experiment is conducted which investigates the effect of changing the stiffness of an intermediate support coupling the two panels of a double-leaf partition in which a vacuum has been applied to the inner cavity. The available equipment was able to maintain a 99% vacuum between the panels. Both experiments are accompanied by analytical models used to investigate the importance of various dynamic parameters. Results show that the vacuum-sealed system shows some potential for increased transmission loss, primarily by the changing the natural frequencies of the double-leaf partition.

  20. Does the oviparity-viviparity transition alter the partitioning of yolk in embryonic snakes?

    Science.gov (United States)

    Wu, Yan-Qing; Qu, Yan-Fu; Wang, Xue-Ji; Gao, Jian-Fang; Ji, Xiang

    2017-11-29

    The oviparity-viviparity transition is a major evolutionary event, likely altering the reproductive process of the organisms involved. Residual yolk, a portion of yolk remaining unutilized at hatching or birth as parental investment in care, has been investigated in many oviparous amniotes but remained largely unknown in viviparous species. Here, we used data from 20 (12 oviparous and 8 viviparous) species of snakes to see if the oviparity-viviparity transition alters the partitioning of yolk in embryonic snakes. We used ANCOVA to test whether offspring size, mass and components at hatching or birth differed between the sexes in each species. We used both ordinary least squares and phylogenetic generalized least squares regressions to test whether relationships between selected pairs of offspring components were significant. We used phylogenetic ANOVA to test whether offspring components differed between oviparous and viviparous species and, more specifically, the hypothesis that viviparous snakes invest more in the yolk as parental investment in embryogenesis to produce more well developed offspring that are larger in linear size. In none of the 20 species was sex a significant source of variation in any offspring component examined. Newborn viviparous snakes on average contained proportionally more water and, after accounting for body dry mass, had larger carcasses but smaller residual yolks than did newly hatched oviparous snakes. The rates at which carcass dry mass (CDM) and fat body dry mass (FDM) increased with residual yolk dry mass (YDM) did not differ between newborn oviparous and viviparous snakes. Neither CDM nor FDM differed between newborn oviparous and viviparous snakes after accounting for YDM. Our results are not consistent with the hypothesis that the partitioning of yolk between embryonic and post-embryonic stages differs between snakes that differ in parity mode, but instead show that the partitioning of yolk in embryonic snakes is species

  1. Common y-intercept and single compound regressions of gas-particle partitioning data vs 1/T

    Science.gov (United States)

    Pankow, James F.

    Confidence intervals are placed around the log Kp vs 1/ T correlation equations obtained using simple linear regressions (SLR) with the gas-particle partitioning data set of Yamasaki et al. [(1982) Env. Sci. Technol.16, 189-194]. The compounds and groups of compounds studied include the polycylic aromatic hydrocarbons phenanthrene + anthracene, me-phenanthrene + me-anthracene, fluoranthene, pyrene, benzo[ a]fluorene + benzo[ b]fluorene, chrysene + benz[ a]anthracene + triphenylene, benzo[ b]fluoranthene + benzo[ k]fluoranthene, and benzo[ a]pyrene + benzo[ e]pyrene (note: me = methyl). For any given compound, at equilibrium, the partition coefficient Kp equals ( F/ TSP)/ A where F is the particulate-matter associated concentration (ng m -3), A is the gas-phase concentration (ng m -3), and TSP is the concentration of particulate matter (μg m -3). At temperatures more than 10°C from the mean sampling temperature of 17°C, the confidence intervals are quite wide. Since theory predicts that similar compounds sorbing on the same particulate matter should possess very similar y-intercepts, the data set was also fitted using a special common y-intercept regression (CYIR). For most of the compounds, the CYIR equations fell inside of the SLR 95% confidence intervals. The CYIR y-intercept value is -18.48, and is reasonably close to the type of value that can be predicted for PAH compounds. The set of CYIR regression equations is probably more reliable than the set of SLR equations. For example, the CYIR-derived desorption enthalpies are much more highly correlated with vaporization enthalpies than are the SLR-derived desorption enthalpies. It is recommended that the CYIR approach be considered whenever analysing temperature-dependent gas-particle partitioning data.

  2. Partitions in languages and parallel computations

    Energy Technology Data Exchange (ETDEWEB)

    Burgin, M S; Burgina, E S

    1982-05-01

    Partitions of entries (linguistic structures) are studied that are intended for parallel data processing. The representations of formal languages with the aid of such structures is examined, and the relationships are considered between partitions of entries and abstract families of languages and automata. 18 references.

  3. 13 CFR 121.412 - What are the size procedures for partial small business set-asides?

    Science.gov (United States)

    2010-01-01

    ... Requirements for Government Procurement § 121.412 What are the size procedures for partial small business set... portion of a procurement, and is not required to qualify as a small business for the unrestricted portion. ...

  4. Scheduling Driven Partitioning of Heterogeneous Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    1998-01-01

    In this paper we present an algorithm for system level hardware/software partitioning of heterogeneous embedded systems. The system is represented as an abstract graph which captures both data-flow and the flow of control. Given an architecture consisting of several processors, ASICs and shared...... busses, our partitioning algorithm finds the partitioning with the smallest hardware cost and is able to predict and guarantee the performance of the system in terms of worst case delay....

  5. The wave function behavior of the open topological string partition function on the conifold

    International Nuclear Information System (INIS)

    Kashani-Poor, Amir-Kian

    2007-01-01

    We calculate the topological string partition function to all genus on the conifold, in the presence of branes. We demonstrate that the partition functions for different brane backgrounds (smoothly connected along a quantum corrected moduli space) can be interpreted as the same wave function in different polarizations. This behavior has a natural interpretation in the Chern-Simons target space description of the topological theory. Our detailed analysis however indicates that non-perturbatively, a modification of real Chern-Simons theory is required to capture the correct target space theory of the topological string. We perform our calculations in the framework of a free fermion representation of the open topological string, demonstrating that this framework extends beyond the simple C 3 geometry. The notion of a fermionic brane creation operator arises in this setting, and we study to what extent the wave function properties of the partition function can be extended to this operator

  6. Partition functions for supersymmetric black holes

    NARCIS (Netherlands)

    Manschot, J.

    2008-01-01

    This thesis presents a number of results on partition functions for four-dimensional supersymmetric black holes. These partition functions are important tools to explain the entropy of black holes from a microscopic point of view. Such a microscopic explanation was desired after the association of a

  7. Details Matter: Noise and Model Structure Set the Relationship between Cell Size and Cell Cycle Timing

    Directory of Open Access Journals (Sweden)

    Felix Barber

    2017-11-01

    Full Text Available Organisms across all domains of life regulate the size of their cells. However, the means by which this is done is poorly understood. We study two abstracted “molecular” models for size regulation: inhibitor dilution and initiator accumulation. We apply the models to two settings: bacteria like Escherichia coli, that grow fully before they set a division plane and divide into two equally sized cells, and cells that form a bud early in the cell division cycle, confine new growth to that bud, and divide at the connection between that bud and the mother cell, like the budding yeast Saccharomyces cerevisiae. In budding cells, delaying cell division until buds reach the same size as their mother leads to very weak size control, with average cell size and standard deviation of cell size increasing over time and saturating up to 100-fold higher than those values for cells that divide when the bud is still substantially smaller than its mother. In budding yeast, both inhibitor dilution or initiator accumulation models are consistent with the observation that the daughters of diploid cells add a constant volume before they divide. This “adder” behavior has also been observed in bacteria. We find that in bacteria an inhibitor dilution model produces adder correlations that are not robust to noise in the timing of DNA replication initiation or in the timing from initiation of DNA replication to cell division (the C+D period. In contrast, in bacteria an initiator accumulation model yields robust adder correlations in the regime where noise in the timing of DNA replication initiation is much greater than noise in the C + D period, as reported previously (Ho and Amir, 2015. In bacteria, division into two equally sized cells does not broaden the size distribution.

  8. Aspects of system modelling in Hardware/Software partitioning

    DEFF Research Database (Denmark)

    Knudsen, Peter Voigt; Madsen, Jan

    1996-01-01

    This paper addresses fundamental aspects of system modelling and partitioning algorithms in the area of Hardware/Software Codesign. Three basic system models for partitioning are presented and the consequences of partitioning according to each of these are analyzed. The analysis shows...... the importance of making a clear distinction between the model used for partitioning and the model used for evaluation It also illustrates the importance of having a realistic hardware model such that hardware sharing can be taken into account. Finally, the importance of integrating scheduling and allocation...

  9. Geometric measures of multipartite entanglement in finite-size spin chains

    Energy Technology Data Exchange (ETDEWEB)

    Blasone, M; Dell' Anno, F; De Siena, S; Giampaolo, S M; Illuminati, F, E-mail: illuminati@sa.infn.i [Dipartimento di Matematica e Informatica, Universita degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy)

    2010-09-01

    We investigate the behaviour of multipartite entanglement in finite-size quantum spin systems, resorting to a hierarchy of geometric measures of multipartite entanglement recently introduced in the literature. In particular, we investigate the ground-state entanglement in the XY model defined on finite chains of N sites with periodic boundary conditions. We analyse the behaviour of the geometric measures of (N- 1)-partite and (N/2)-partite entanglement and compare them with the Wei-Goldbart geometric measure of global entanglement.

  10. Geometric measures of multipartite entanglement in finite-size spin chains

    International Nuclear Information System (INIS)

    Blasone, M; Dell'Anno, F; De Siena, S; Giampaolo, S M; Illuminati, F

    2010-01-01

    We investigate the behaviour of multipartite entanglement in finite-size quantum spin systems, resorting to a hierarchy of geometric measures of multipartite entanglement recently introduced in the literature. In particular, we investigate the ground-state entanglement in the XY model defined on finite chains of N sites with periodic boundary conditions. We analyse the behaviour of the geometric measures of (N- 1)-partite and (N/2)-partite entanglement and compare them with the Wei-Goldbart geometric measure of global entanglement.

  11. Generating Milton Babbitt's all-partition arrays

    DEFF Research Database (Denmark)

    Bemman, Brian; Meredith, David

    2016-01-01

    In most of Milton Babbitt's (1916–2011) works written since the early 1960s, both the pitch and rhythmic content is organized according to a highly constrained structure known as the all-partition array. The all-partition array provides a framework that ensures that as many different forms...

  12. Dynamically heterogenous partitions and phylogenetic inference: an evaluation of analytical strategies with cytochrome b and ND6 gene sequences in cranes.

    Science.gov (United States)

    Krajewski, C; Fain, M G; Buckley, L; King, D G

    1999-11-01

    ki ctes over whether molecular sequence data should be partitioned for phylogenetic analysis often confound two types of heterogeneity among partitions. We distinguish historical heterogeneity (i.e., different partitions have different evolutionary relationships) from dynamic heterogeneity (i.e., different partitions show different patterns of sequence evolution) and explore the impact of the latter on phylogenetic accuracy and precision with a two-gene, mitochondrial data set for cranes. The well-established phylogeny of cranes allows us to contrast tree-based estimates of relevant parameter values with estimates based on pairwise comparisons and to ascertain the effects of incorporating different amounts of process information into phylogenetic estimates. We show that codon positions in the cytochrome b and NADH dehydrogenase subunit 6 genes are dynamically heterogenous under both Poisson and invariable-sites + gamma-rates versions of the F84 model and that heterogeneity includes variation in base composition and transition bias as well as substitution rate. Estimates of transition-bias and relative-rate parameters from pairwise sequence comparisons were comparable to those obtained as tree-based maximum likelihood estimates. Neither rate-category nor mixed-model partitioning strategies resulted in a loss of phylogenetic precision relative to unpartitioned analyses. We suggest that weighted-average distances provide a computationally feasible alternative to direct maximum likelihood estimates of phylogeny for mixed-model analyses of large, dynamically heterogenous data sets. Copyright 1999 Academic Press.

  13. Partition function zeros for the one-dimensional ordered plasma in Dirichlet boundary conditions

    International Nuclear Information System (INIS)

    Roumeliotis, J.; Smith, E.R.

    1992-01-01

    The authors consider the grand canonical partition function for the ordered one-dimensional, two-component plasma at fugacity ζ in an applied electric field E with Dirichlet boundary conditions. The system has a phase transition from a low-coupling phase with equally spaced particles to a high-coupling phase with particles clustered into dipolar pairs. An exact expression for the partition function is developed. In zero applied field the zeros in the ζ plane occupy the imaginary axis from -i∞ to -iζ c and iζ c to i∞ for some ζ c . They also occupy the diamond shape of four straight lines from ±iζ c to ζ c and from ±iζ c to -ζ c . The fugacity ζ acts like a temperature or coupling variable. The symmetry-breaking field is the applied electric field E. A finite-size scaling representation for the partition in scaled coupling and scaled electric field is developed. It has standard mean field form. When the scaled coupling is real, the zeros in the scaled field lie on the imaginary axis and pinch the real scaled field axis as the scaled coupling increases. The scaled partition function considered as a function of two complex variables, scaled coupling and scaled field, has zeros on a two-dimensional surface in a domain of four real variables. A numerical discussion of some of the properties of this surface is presented

  14. Matrix string partition function

    CERN Document Server

    Kostov, Ivan K; Kostov, Ivan K.; Vanhove, Pierre

    1998-01-01

    We evaluate quasiclassically the Ramond partition function of Euclidean D=10 U(N) super Yang-Mills theory reduced to a two-dimensional torus. The result can be interpreted in terms of free strings wrapping the space-time torus, as expected from the point of view of Matrix string theory. We demonstrate that, when extrapolated to the ultraviolet limit (small area of the torus), the quasiclassical expressions reproduce exactly the recently obtained expression for the partition of the completely reduced SYM theory, including the overall numerical factor. This is an evidence that our quasiclassical calculation might be exact.

  15. Partitioning and desorption behavior of polycyclic aromatic hydrocarbons from disparate sources

    International Nuclear Information System (INIS)

    Reeves, W.R.; McDonald, T.J.; Cizmas, L.; Donnelly, K.C.

    2004-01-01

    Contaminated sediments pose a unique challenge for risk assessment or remediation because the overlying water column may transport contaminants offsite or to ecological receptors. This research compares the behavior of polycyclic aromatic hydrocarbons (PAHs) on marine sediments from two sites. The first site was affected by shipping activities and the second was impacted by a creosote seep. Organic carbon:water partitioning coefficients (K oc values) were measured with three solutions. Desorption was measured using Tenax beads. PAHs from the ship channel had lower K oc values than those from the creosote facility. For example, the average log K oc value of ship channel pyrene was significantly lower than that of creosote facility pyrene (4.39±0.35 and 5.29±0.09, respectively, when tested in 5 mM calcium chloride). These results were consistent with the greater desorption of pyrene, phenanthrene and benzo(a)pyrene from the ship channel than from the creosote facility sediments. Organic compound desorption from sediments can be considered to be a two-stage process, with a labile fraction that desorbs quickly and a refractory fraction that desorbs much more slowly. In both sediments, more than 75% of the benzo(a)pyrene was found to have partitioned into the refractory phase. The amounts of phenanthrene and pyrene that partitioned into the refractory phase were lower. Linear correlations of log K oc with log (C R /C L ) (where C R and C L are the fractions of the compound in the refractory and labile phases, respectively, at time zero) showed that partitioning measurements made with the US EPA's Toxicity Characteristic Leaching Procedure fluid (US EPA, 1996) most closely matched predictions of desorption behavior. The data imply that with a larger data set, it may be possible to relate simple partitioning measurements to desorption behavior. Partitioning measurements were used to predict water concentrations. Despite having higher concentrations of carcinogenic PAHs

  16. Combinatorics of finite sets

    CERN Document Server

    Anderson, Ian

    2011-01-01

    Coherent treatment provides comprehensive view of basic methods and results of the combinatorial study of finite set systems. The Clements-Lindstrom extension of the Kruskal-Katona theorem to multisets is explored, as is the Greene-Kleitman result concerning k-saturated chain partitions of general partially ordered sets. Connections with Dilworth's theorem, the marriage problem, and probability are also discussed. Each chapter ends with a helpful series of exercises and outline solutions appear at the end. ""An excellent text for a topics course in discrete mathematics."" - Bulletin of the Ame

  17. Role of crucible partition in improving Czochralski melt conditions

    Science.gov (United States)

    Jafri, I. H.; Prasad, V.; Anselmo, A. P.; Gupta, K. P.

    1995-09-01

    Many of the inhomogeneities and defects in the crystal grown from a pool of melt are because of the inherent unsteady growth kinetics and flow instabilities of the process. A scaled up version of the Czochralski process induces oscillatory and turbulent conditions in the melt, thereby resulting in the production of non-uniform silicon crystals. This numerical study reveals that a crucible partition shorter than the melt height can significantly improve the melt conditions. The obstruction at the bottom of the crucible is helpful but the variations in heat flux and flow patterns remain random. However, when the obstruction is introduced at the top of the melt, the flow conditions become much more desirable and oscillations are greatly suppressed. It is also found that a full-melt height partition or a double-crucible may not be a good choice. An optimal size of the blockage and its location to produce the most desirable process conditions will depend on the growth parameters including the melt height and the crucible diameter. These findings should be particularly useful in designing a solid polysilicon pellets-feed continuous Czochralski process for Si crystals.

  18. Size distribution of rare earth elements in coal ash

    Science.gov (United States)

    Scott, Clinton T.; Deonarine, Amrika; Kolker, Allan; Adams, Monique; Holland, James F.

    2015-01-01

    Rare earth elements (REEs) are utilized in various applications that are vital to the automotive, petrochemical, medical, and information technology industries. As world demand for REEs increases, critical shortages are expected. Due to the retention of REEs during coal combustion, coal fly ash is increasingly considered a potential resource. Previous studies have demonstrated that coal fly ash is variably enriched in REEs relative to feed coal (e.g, Seredin and Dai, 2012) and that enrichment increases with decreasing size fractions (Blissett et al., 2014). In order to further explore the REE resource potential of coal ash, and determine the partitioning behavior of REE as a function of grain size, we studied whole coal and fly ash size-fractions collected from three U.S commercial-scale coal-fired generating stations burning Appalachian or Powder River Basin coal. Whole fly ash was separated into , 5 um, to 5 to 10 um and 10 to 100 um particle size fractions by mechanical shaking using trace-metal clean procedures. In these samples REE enrichments in whole fly ash ranges 5.6 to 18.5 times that of feedcoals. Partitioning results for size separates relative to whole coal and whole fly ash will also be reported. 

  19. Pattern-set generation algorithm for the one-dimensional multiple stock sizes cutting stock problem

    Science.gov (United States)

    Cui, Yaodong; Cui, Yi-Ping; Zhao, Zhigang

    2015-09-01

    A pattern-set generation algorithm (PSG) for the one-dimensional multiple stock sizes cutting stock problem (1DMSSCSP) is presented. The solution process contains two stages. In the first stage, the PSG solves the residual problems repeatedly to generate the patterns in the pattern set, where each residual problem is solved by the column-generation approach, and each pattern is generated by solving a single large object placement problem. In the second stage, the integer linear programming model of the 1DMSSCSP is solved using a commercial solver, where only the patterns in the pattern set are considered. The computational results of benchmark instances indicate that the PSG outperforms existing heuristic algorithms and rivals the exact algorithm in solution quality.

  20. Multivariate modeling of complications with data driven variable selection: Guarding against overfitting and effects of data set size

    International Nuclear Information System (INIS)

    Schaaf, Arjen van der; Xu Chengjian; Luijk, Peter van; Veld, Aart A. van’t; Langendijk, Johannes A.; Schilstra, Cornelis

    2012-01-01

    Purpose: Multivariate modeling of complications after radiotherapy is frequently used in conjunction with data driven variable selection. This study quantifies the risk of overfitting in a data driven modeling method using bootstrapping for data with typical clinical characteristics, and estimates the minimum amount of data needed to obtain models with relatively high predictive power. Materials and methods: To facilitate repeated modeling and cross-validation with independent datasets for the assessment of true predictive power, a method was developed to generate simulated data with statistical properties similar to real clinical data sets. Characteristics of three clinical data sets from radiotherapy treatment of head and neck cancer patients were used to simulate data with set sizes between 50 and 1000 patients. A logistic regression method using bootstrapping and forward variable selection was used for complication modeling, resulting for each simulated data set in a selected number of variables and an estimated predictive power. The true optimal number of variables and true predictive power were calculated using cross-validation with very large independent data sets. Results: For all simulated data set sizes the number of variables selected by the bootstrapping method was on average close to the true optimal number of variables, but showed considerable spread. Bootstrapping is more accurate in selecting the optimal number of variables than the AIC and BIC alternatives, but this did not translate into a significant difference of the true predictive power. The true predictive power asymptotically converged toward a maximum predictive power for large data sets, and the estimated predictive power converged toward the true predictive power. More than half of the potential predictive power is gained after approximately 200 samples. Our simulations demonstrated severe overfitting (a predicative power lower than that of predicting 50% probability) in a number of small

  1. A Group Theoretic Approach to Metaheuristic Local Search for Partitioning Problems

    Science.gov (United States)

    2005-05-01

    Tabu Search. Mathematical and Computer Modeling 39: 599-616. 107 Daskin , M.S., E. Stern. 1981. A Hierarchical Objective Set Covering Model for EMS... A Group Theoretic Approach to Metaheuristic Local Search for Partitioning Problems by Gary W. Kinney Jr., B.G.S., M.S. Dissertation Presented to the...DISTRIBUTION STATEMENT A Approved for Public Release Distribution Unlimited The University of Texas at Austin May, 2005 20050504 002 REPORT

  2. QSPR modeling of octanol/water partition coefficient of antineoplastic agents by balance of correlations.

    Science.gov (United States)

    Toropov, Andrey A; Toropova, Alla P; Raska, Ivan; Benfenati, Emilio

    2010-04-01

    Three different splits into the subtraining set (n = 22), the set of calibration (n = 21), and the test set (n = 12) of 55 antineoplastic agents have been examined. By the correlation balance of SMILES-based optimal descriptors quite satisfactory models for the octanol/water partition coefficient have been obtained on all three splits. The correlation balance is the optimization of a one-variable model with a target function that provides both the maximal values of the correlation coefficient for the subtraining and calibration set and the minimum of the difference between the above-mentioned correlation coefficients. Thus, the calibration set is a preliminary test set. Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.

  3. Prediction of Partition Coefficients of Organic Compounds for SPME/PDMS

    Directory of Open Access Journals (Sweden)

    Liao Hsuan-Yu

    2016-01-01

    Full Text Available The partition coefficients of 51 organic compounds between SPME/PDMS and gas were compiled from the literature sources in this study. The effect of physicochemical properties and descriptors on the partitioning process of partition coefficients was explicated by the correlation analysis. The PDMS-gas partition coefficients were well correlated to the molecular weight of organic compounds (r = 0.832, p < 0.05. An empirical model, consisting of the molecular weight and the polarizability, was developed to appropriately predict the partition coefficients of organic compounds. The empirical model for estimating the PDMS-gas partition coefficient will contribute to the practical applications of the SPME technique.

  4. Generating a taxonomy of spatially cued attention for visual discrimination: Effects of judgment precision and set size on attention

    Science.gov (United States)

    Hetley, Richard; Dosher, Barbara Anne; Lu, Zhong-Lin

    2014-01-01

    Attention precues improve the performance of perceptual tasks in many but not all circumstances. These spatial attention effects may depend upon display set size or workload, and have been variously attributed to external noise filtering, stimulus enhancement, contrast gain, or response gain, or to uncertainty or other decision effects. In this study, we document systematically different effects of spatial attention in low- and high-precision judgments, with and without external noise, and in different set sizes in order to contribute to the development of a taxonomy of spatial attention. An elaborated perceptual template model (ePTM) provides an integrated account of a complex set of effects of spatial attention with just two attention factors: a set-size dependent exclusion or filtering of external noise and a narrowing of the perceptual template to focus on the signal stimulus. These results are related to the previous literature by classifying the judgment precision and presence of external noise masks in those experiments, suggesting a taxonomy of spatially cued attention in discrimination accuracy. PMID:24939234

  5. Generating a taxonomy of spatially cued attention for visual discrimination: effects of judgment precision and set size on attention.

    Science.gov (United States)

    Hetley, Richard; Dosher, Barbara Anne; Lu, Zhong-Lin

    2014-11-01

    Attention precues improve the performance of perceptual tasks in many but not all circumstances. These spatial attention effects may depend upon display set size or workload, and have been variously attributed to external noise filtering, stimulus enhancement, contrast gain, or response gain, or to uncertainty or other decision effects. In this study, we document systematically different effects of spatial attention in low- and high-precision judgments, with and without external noise, and in different set sizes in order to contribute to the development of a taxonomy of spatial attention. An elaborated perceptual template model (ePTM) provides an integrated account of a complex set of effects of spatial attention with just two attention factors: a set-size dependent exclusion or filtering of external noise and a narrowing of the perceptual template to focus on the signal stimulus. These results are related to the previous literature by classifying the judgment precision and presence of external noise masks in those experiments, suggesting a taxonomy of spatially cued attention in discrimination accuracy.

  6. Submatrices of character tables and basic sets

    DEFF Research Database (Denmark)

    Bessenrodt, Christine; Olsson, Jørn Børling

    2012-01-01

    In this investigation of character tables of nite groups we study basic sets and associated representation theoretic data for complementary sets of conjugacy lasses. For the symmetric groups we nd unexpected properties of characters on restricted sets of conjugacy classes, like beautiful...... combinatorial determinant formulae for submatrices of the character table and Cartan matrices with respect to basic sets; we observe that similar phenomena occur for the transition matrices between power sum symmetric functions to bounded partitions and the k-Schur functions dened by Lapointe and Morse...

  7. Understanding who benefits at each step in an internet-based diabetes self-management program: application of a recursive partitioning approach.

    Science.gov (United States)

    Glasgow, Russell E; Strycker, Lisa A; King, Diane K; Toobert, Deborah J

    2014-02-01

    Efforts to predict success in chronic disease management programs have been generally unsuccessful. To identify patient subgroups associated with success at each of 6 steps in a diabetes self-management (DSM) program. Using data from a randomized trial, recursive partitioning with signal detection analysis was used to identify subgroups associated with 6 sequential steps of program success: agreement to participate, completion of baseline, initial website engagement, 4-month behavior change, later engagement, and longer-term maintenance. The study was conducted in 5 primary care clinics within Kaiser Permanente Colorado. Different numbers of patients participated in each step, including 2076, 544, 270, 219, 127, and 89. All measures available were used to address success at each step. Intervention. Participants were randomized to receive either enhanced usual care or 1 of 2 Internet-based DSM programs: 1) self-administered, computer-assisted self-management and 2) the self-administered program with the addition of enhanced social support. Two sets of potential predictor variables and 6 dichotomous outcomes were created. Signal detection analysis differentiated successful and unsuccessful subgroups at all but the final step. Different patient subgroups were associated with success at these different steps. Demographic factors (education, ethnicity, income) were associated with initial participation but not with later steps, and the converse was true of health behavior variables. Analyses were limited to one setting, and the sample sizes for some of the steps were modest. Signal detection and recursive partitioning methods may be useful for identifying subgroups that are more or less successful at different steps of intervention and may aid in understanding variability in outcomes.

  8. Combined spectroscopic imaging and chemometric approach for automatically partitioning tissue types in human prostate tissue biopsies

    Science.gov (United States)

    Haka, Abigail S.; Kidder, Linda H.; Lewis, E. Neil

    2001-07-01

    We have applied Fourier transform infrared (FTIR) spectroscopic imaging, coupling a mercury cadmium telluride (MCT) focal plane array detector (FPA) and a Michelson step scan interferometer, to the investigation of various states of malignant human prostate tissue. The MCT FPA used consists of 64x64 pixels, each 61 micrometers 2, and has a spectral range of 2-10.5 microns. Each imaging data set was collected at 16-1 resolution, resulting in 512 image planes and a total of 4096 interferograms. In this article we describe a method for separating different tissue types contained within FTIR spectroscopic imaging data sets of human prostate tissue biopsies. We present images, generated by the Fuzzy C-Means clustering algorithm, which demonstrate the successful partitioning of distinct tissue type domains. Additionally, analysis of differences in the centroid spectra corresponding to different tissue types provides an insight into their biochemical composition. Lastly, we demonstrate the ability to partition tissue type regions in a different data set using centroid spectra calculated from the original data set. This has implications for the use of the Fuzzy C-Means algorithm as an automated technique for the separation and examination of tissue domains in biopsy samples.

  9. Variable length adjacent partitioning for PTS based PAPR reduction of OFDM signal

    International Nuclear Information System (INIS)

    Ibraheem, Zeyid T.; Rahman, Md. Mijanur; Yaakob, S. N.; Razalli, Mohammad Shahrazel; Kadhim, Rasim A.

    2015-01-01

    Peak-to-Average power ratio (PAPR) is a major drawback in OFDM communication. It leads the power amplifier into nonlinear region operation resulting into loss of data integrity. As such, there is a strong motivation to find techniques to reduce PAPR. Partial Transmit Sequence (PTS) is an attractive scheme for this purpose. Judicious partitioning the OFDM data frame into disjoint subsets is a pivotal component of any PTS scheme. Out of the existing partitioning techniques, adjacent partitioning is characterized by an attractive trade-off between cost and performance. With an aim of determining effects of length variability of adjacent partitions, we performed an investigation into the performances of a variable length adjacent partitioning (VL-AP) and fixed length adjacent partitioning in comparison with other partitioning schemes such as pseudorandom partitioning. Simulation results with different modulation and partitioning scenarios showed that fixed length adjacent partition had better performance compared to variable length adjacent partitioning. As expected, simulation results showed a slightly better performance of pseudorandom partitioning technique compared to fixed and variable adjacent partitioning schemes. However, as the pseudorandom technique incurs high computational complexities, adjacent partitioning schemes were still seen as favorable candidates for PAPR reduction

  10. Variable length adjacent partitioning for PTS based PAPR reduction of OFDM signal

    Energy Technology Data Exchange (ETDEWEB)

    Ibraheem, Zeyid T.; Rahman, Md. Mijanur; Yaakob, S. N.; Razalli, Mohammad Shahrazel; Kadhim, Rasim A. [School of Computer and Communication Engineering, Universiti Malaysia Perlis, 02600 Arau, Perlis (Malaysia)

    2015-05-15

    Peak-to-Average power ratio (PAPR) is a major drawback in OFDM communication. It leads the power amplifier into nonlinear region operation resulting into loss of data integrity. As such, there is a strong motivation to find techniques to reduce PAPR. Partial Transmit Sequence (PTS) is an attractive scheme for this purpose. Judicious partitioning the OFDM data frame into disjoint subsets is a pivotal component of any PTS scheme. Out of the existing partitioning techniques, adjacent partitioning is characterized by an attractive trade-off between cost and performance. With an aim of determining effects of length variability of adjacent partitions, we performed an investigation into the performances of a variable length adjacent partitioning (VL-AP) and fixed length adjacent partitioning in comparison with other partitioning schemes such as pseudorandom partitioning. Simulation results with different modulation and partitioning scenarios showed that fixed length adjacent partition had better performance compared to variable length adjacent partitioning. As expected, simulation results showed a slightly better performance of pseudorandom partitioning technique compared to fixed and variable adjacent partitioning schemes. However, as the pseudorandom technique incurs high computational complexities, adjacent partitioning schemes were still seen as favorable candidates for PAPR reduction.

  11. Neuromuscular partitioning, architectural design, and myosin fiber types of the M. vastus lateralis of the llama (Lama glama).

    Science.gov (United States)

    Graziotti, Guillermo H; Palencia, Pablo; Delhon, Gustavo; Rivero, José-Luis L

    2004-11-01

    The llama (Lama glama) is one of the few mammals of relatively large body size in which three fast myosin heavy chain isoforms (i.e., IIA, IIX, IIB) are extensively expressed in their locomotory muscles. This study was designed to gain insight into the morphological and functional organization of skeletal musculature in this peculiar animal model. The neuromuscular partitioning, architectural design, and myosin fiber types were systematically studied in the M. vastus lateralis of adult llamas (n = 15). Four nonoverlapping neuromuscular partitions or compartments were identified macroscopically (using a modified Sihler's technique for muscle depigmentation), although they did not conform strictly to the definitions of "neuromuscular compartments." Each neuromuscular partition was innervated by primary branches of the femoral nerve and was arranged within the muscle as paired partitions, two in parallel (deep-superficial compartmentalization) and the other two in-series (proximo-distal compartmentalization). These neuromuscular partitions of the muscle varied in their respective architectural designs (studied after partial digestion with diluted nitric acid) and myosin fiber type characteristics (identified immunohistochemically with specific anti-myosin monoclonal antibodies, then examined by quantitative histochemistry and image analysis). The deep partitions of the muscle had longer fibers, with lower angles of pinnation, and higher percentages of fast-glycolytic fibers than the superficial partitions of the muscle. These differences clearly suggest a division of labor in the whole M. vastus lateralis of llamas, with deep partitions exhibiting features well adapted for dynamic activities in the extension of stifle, whereas superficial portions seem to be related to the antigravitational role of the muscle in preserving the extension of the stifle during standing and stance phase of the stride. This peculiar structural and functional organization of the llama M

  12. Phase Grouping Line Extraction Algorithm Using Overlapped Partition

    Directory of Open Access Journals (Sweden)

    WANG Jingxue

    2015-07-01

    Full Text Available Aiming at solving the problem of fracture at the discontinuities area and the challenges of line fitting in each partition, an innovative line extraction algorithm is proposed based on phase grouping using overlapped partition. The proposed algorithm adopted dual partition steps, which will generate overlapped eight partitions. Between the two steps, the middle axis in the first step coincides with the border lines in the other step. Firstly, the connected edge points that share the same phase gradients are merged into the line candidates, and fitted into line segments. Then to remedy the break lines at the border areas, the break segments in the second partition steps are refitted. The proposed algorithm is robust and does not need any parameter tuning. Experiments with various datasets have confirmed that the method is not only capable of handling the linear features, but also powerful enough in handling the curve features.

  13. A Full-size High Temperature Superconducting Coil Employed in a Wind Turbine Generator Set-up

    DEFF Research Database (Denmark)

    Song, Xiaowei (Andy); Mijatovic, Nenad; Kellers, Jürgen

    2016-01-01

    A full-size stationary experimental set-up, which is a pole pair segment of a 2 MW high temperature superconducting (HTS) wind turbine generator, has been built and tested under the HTS-GEN project in Denmark. The performance of the HTS coil is crucial to the set-up, and further to the development...... is tested in LN2 first, and then tested in the set-up so that the magnetic environment in a real generator is reflected. The experimental results are reported, followed by a finite element simulation and a discussion on the deviation of the results. The tested and estimated Ic in LN2 are 148 A and 143 A...

  14. Analytical model for macromolecular partitioning during yeast cell division

    International Nuclear Information System (INIS)

    Kinkhabwala, Ali; Khmelinskii, Anton; Knop, Michael

    2014-01-01

    Asymmetric cell division, whereby a parent cell generates two sibling cells with unequal content and thereby distinct fates, is central to cell differentiation, organism development and ageing. Unequal partitioning of the macromolecular content of the parent cell — which includes proteins, DNA, RNA, large proteinaceous assemblies and organelles — can be achieved by both passive (e.g. diffusion, localized retention sites) and active (e.g. motor-driven transport) processes operating in the presence of external polarity cues, internal asymmetries, spontaneous symmetry breaking, or stochastic effects. However, the quantitative contribution of different processes to the partitioning of macromolecular content is difficult to evaluate. Here we developed an analytical model that allows rapid quantitative assessment of partitioning as a function of various parameters in the budding yeast Saccharomyces cerevisiae. This model exposes quantitative degeneracies among the physical parameters that govern macromolecular partitioning, and reveals regions of the solution space where diffusion is sufficient to drive asymmetric partitioning and regions where asymmetric partitioning can only be achieved through additional processes such as motor-driven transport. Application of the model to different macromolecular assemblies suggests that partitioning of protein aggregates and episomes, but not prions, is diffusion-limited in yeast, consistent with previous reports. In contrast to computationally intensive stochastic simulations of particular scenarios, our analytical model provides an efficient and comprehensive overview of partitioning as a function of global and macromolecule-specific parameters. Identification of quantitative degeneracies among these parameters highlights the importance of their careful measurement for a given macromolecular species in order to understand the dominant processes responsible for its observed partitioning

  15. Body size mediated coexistence of consumers competing for resources in space

    Science.gov (United States)

    Basset, A.; Angelis, D.L.

    2007-01-01

    Body size is a major phenotypic trait of individuals that commonly differentiates co-occurring species. We analyzed inter-specific competitive interactions between a large consumer and smaller competitors, whose energetics, selection and giving-up behaviour on identical resource patches scaled with individual body size. The aim was to investigate whether pure metabolic constraints on patch behaviour of vagile species can determine coexistence conditions consistent with existing theoretical and experimental evidence. We used an individual-based spatially explicit simulation model at a spatial scale defined by the home range of the large consumer, which was assumed to be parthenogenic and semelparous. Under exploitative conditions, competitive coexistence occurred in a range of body size ratios between 2 and 10. Asymmetrical competition and the mechanism underlying asymmetry, determined by the scaling of energetics and patch behaviour with consumer body size, were the proximate determinant of inter-specific coexistence. The small consumer exploited patches more efficiently, but searched for profitable patches less effectively than the larger competitor. Therefore, body-size related constraints induced niche partitioning, allowing competitive coexistence within a set of conditions where the large consumer maintained control over the small consumer and resource dynamics. The model summarises and extends the existing evidence of species coexistence on a limiting resource, and provides a mechanistic explanation for decoding the size-abundance distribution patterns commonly observed at guild and community levels. ?? Oikos.

  16. Calibration sets and the accuracy of vibrational scaling factors: A case study with the X3LYP hybrid functional

    Science.gov (United States)

    Teixeira, Filipe; Melo, André; Cordeiro, M. Natália D. S.

    2010-09-01

    A linear least-squares methodology was used to determine the vibrational scaling factors for the X3LYP density functional. Uncertainties for these scaling factors were calculated according to the method devised by Irikura et al. [J. Phys. Chem. A 109, 8430 (2005)]. The calibration set was systematically partitioned according to several of its descriptors and the scaling factors for X3LYP were recalculated for each subset. The results show that the scaling factors are only significant up to the second digit, irrespective of the calibration set used. Furthermore, multivariate statistical analysis allowed us to conclude that the scaling factors and the associated uncertainties are independent of the size of the calibration set and strongly suggest the practical impossibility of obtaining vibrational scaling factors with more than two significant digits.

  17. Effects of Single Nucleotide Polymorphism Marker Density on Haplotype Block Partition

    Directory of Open Access Journals (Sweden)

    Sun Ah Kim

    2016-12-01

    Full Text Available Many researchers have found that one of the most important characteristics of the structure of linkage disequilibrium is that the human genome can be divided into non-overlapping block partitions in which only a small number of haplotypes are observed. The location and distribution of haplotype blocks can be seen as a population property influenced by population genetic events such as selection, mutation, recombination and population structure. In this study, we investigate the effects of the density of markers relative to the full set of all polymorphisms in the region on the results of haplotype partitioning for five popular haplotype block partition methods: three methods in Haploview (confidence interval, four gamete test, and solid spine, MIG++ implemented in PLINK 1.9 and S-MIG++. We used several experimental datasets obtained by sampling subsets of single nucleotide polymorphism (SNP markers of chromosome 22 region in the 1000 Genomes Project data and also the HapMap phase 3 data to compare the results of haplotype block partitions by five methods. With decreasing sampling ratio down to 20% of the original SNP markers, the total number of haplotype blocks decreases and the length of haplotype blocks increases for all algorithms. When we examined the marker-independence of the haplotype block locations constructed from the datasets of different density, the results using below 50% of the entire SNP markers were very different from the results using the entire SNP markers. We conclude that the haplotype block construction results should be used and interpreted carefully depending on the selection of markers and the purpose of the study.

  18. Spatial partitions systematize visual search and enhance target memory.

    Science.gov (United States)

    Solman, Grayden J F; Kingstone, Alan

    2017-02-01

    Humans are remarkably capable of finding desired objects in the world, despite the scale and complexity of naturalistic environments. Broadly, this ability is supported by an interplay between exploratory search and guidance from episodic memory for previously observed target locations. Here we examined how the environment itself may influence this interplay. In particular, we examined how partitions in the environment-like buildings, rooms, and furniture-can impact memory during repeated search. We report that the presence of partitions in a display, independent of item configuration, reliably improves episodic memory for item locations. Repeated search through partitioned displays was faster overall and was characterized by more rapid ballistic orienting in later repetitions. Explicit recall was also both faster and more accurate when displays were partitioned. Finally, we found that search paths were more regular and systematic when displays were partitioned. Given the ubiquity of partitions in real-world environments, these results provide important insights into the mechanisms of naturalistic search and its relation to memory.

  19. Partitioning and interfacial tracers for differentiating NAPL entrapment configuration: column-scale investigation.

    Science.gov (United States)

    Dai, D; Barranco, F T; Illangasekare, T H

    2001-12-15

    Research on the use of partitioning and interfacial tracers has led to the development of techniques for estimating subsurface NAPL amount and NAPL-water interfacial area. Although these techniques have been utilized with some success at field sites, current application is limited largely to NAPL at residual saturation, such as for the case of post-remediation settings where mobile NAPL has been removed through product recovery. The goal of this study was to fundamentally evaluate partitioning and interfacial tracer behavior in controlled column-scale test cells for a range of entrapment configurations varying in NAPL saturation, with the results serving as a determinant of technique efficacy (and design protocol) for use with complexly distributed NAPLs, possibly at high saturation, in heterogeneous aquifers. Representative end members of the range of entrapment configurations observed under conditions of natural heterogeneity (an occurrence with residual NAPL saturation [discontinuous blobs] and an occurrence with high NAPL saturation [continuous free-phase LNAPL lens]) were evaluated. Study results indicated accurate prediction (using measured tracer retardation and equilibrium-based computational techniques) of NAPL amount and NAPL-water interfacial area for the case of residual NAPL saturation. For the high-saturation LNAPL lens, results indicated that NAPL-water interfacial area, but not NAPL amount (underpredicted by 35%), can be reasonably determined using conventional computation techniques. Underprediction of NAPL amount lead to an erroneous prediction of NAPL distribution, as indicated by the NAPL morphology index. In light of these results, careful consideration should be given to technique design and critical assumptions before applying equilibrium-based partitioning tracer methodology to settings where NAPLs are complexly entrapped, such as in naturally heterogeneous subsurface formations.

  20. Experiments and Recommendations for Partitioning Systems of Equations

    Directory of Open Access Journals (Sweden)

    Mafteiu-Scai Liviu Octavian

    2014-06-01

    Full Text Available Partitioning the systems of equations is a very important process when solving it on a parallel computer. This paper presents some criteria which leads to more efficient parallelization, that must be taken into consideration. New criteria added to preconditioning process by reducing average bandwidth are pro- posed in this paper. These new criteria lead to a combination between preconditioning and partitioning of systems equations, so no need two distinct algorithms/processes. In our proposed methods - where the preconditioning is done by reducing the average bandwidth- two directions were followed in terms of partitioning: for a given preconditioned system determining the best partitioning (or one as close and the second consist in achieving an adequate preconditioning, depending on a given/desired partitioning. A mixed method it is also proposed. Experimental results, conclusions and recommendations, obtained after parallel implementation of conjugate gradient on IBM BlueGene /P supercomputer- based on a synchronous model of parallelization- are also presented in this paper.

  1. The impact of mass transfer limitations on size distributions of particle associated SVOCs in outdoor and indoor environments

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Cong; Zhang, Yinping [Department of Building Science, Tsinghua University, Beijing (China); Weschler, Charles J., E-mail: weschlch@rwjms.rutgers.edu [Department of Building Science, Tsinghua University, Beijing (China); Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ (United States); International Center for Indoor Environment and Energy, Technical University of Denmark, Lyngby (Denmark)

    2014-11-01

    Semi-volatile organic compounds (SVOCs) partition between the gas phase and airborne particles. The size distribution of particle-associated SVOCs impacts their fate in outdoor and indoor environments, as well as human exposure to these compounds and subsequent health risks. Allen et al. (1996) previously proposed that the rate of mass transfer can impact polycyclic aromatic hydrocarbon (PAH) partitioning among different sized particles, especially for time scales relevant to urban aerosols. The present study quantitatively builds on this idea, presenting a model that incorporates dynamic SVOC/particle interaction and applying this model to typical outdoor and indoor scenarios. The model indicates that the impact of mass transfer limitations on the size distribution of a particle-associated SVOC can be evaluated by the ratio of the time to achieve gas–particle equilibrium relative to the residence time of particles. The higher this ratio, the greater the influence of mass transfer limitations on the size distribution of particle-associated SVOCs. The influence of such constraints is largest on the fraction of particle-associated SVOCs in the coarse mode (> 2 μm). Predictions from the model have been found to be in reasonable agreement with size distributions measured for PAHs at roadside and suburban locations in Japan. The model also quantitatively explains shifts in the size distributions of particle associated SVOCs compared to those for particle mass, and the manner in which these shifts vary with temperature and an SVOC's molecular weight. - Highlights: • Rate of mass transfer can impact SVOC partitioning among different sized particles. • Model was developed that incorporates dynamic SVOC/particle sorption. • Key parameters: mass-transfer coefficients, partition coefficient, residence time • Model explains observed SVOC size distribution shifts with temperature and MW. • Largest impact of mass transfer constraints: SVOC sorption to coarse

  2. Topological string partition functions as polynomials

    International Nuclear Information System (INIS)

    Yamaguchi, Satoshi; Yau Shingtung

    2004-01-01

    We investigate the structure of the higher genus topological string amplitudes on the quintic hypersurface. It is shown that the partition functions of the higher genus than one can be expressed as polynomials of five generators. We also compute the explicit polynomial forms of the partition functions for genus 2, 3, and 4. Moreover, some coefficients are written down for all genus. (author)

  3. Partitioning of selected antioxidants in mayonnaise

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Schwarz, K.; Stockmann, H.

    1999-01-01

    This study examined partitioning of alpha-, beta-, and gamma- tocopherol and six polar antioxidants (Trolox, ferulic acid, caffeic acid, propyl gallate, gallic acid, and catechin) in mayonnaise. Partitioning of antioxidants between different phases was determined after separation of mayonnaise...... acid and catechin) to 83% (Trolox). Accordingly, proportions of 6% (Trolox) to 80% (gallic acid and catechin) were found in the aqueous phase. Similar trends were observed after dialysis. After ultracentrifugation, large proportions of polar antioxidants were found in the "emulsion phase...... by either (a) centrifugation + ultracentrifugation or (b) centrifugation + dialysis. Antioxidants partitioned in accordance with their chemical structure and polarity: Tocopherols were concentrated in the oil phase (93-96%), while the proportion of polar antioxidants in the oil phase ranged from 0% (gallic...

  4. Partitioning of resveratrol between pentane and DMSO

    DEFF Research Database (Denmark)

    Shen, Chen; Stein, Paul C.; Klösgen-Buchkremer, Beate Maria

    2015-01-01

    Partitioning of trans-3,5,4′-trihydroxy-stilbene (resveratrol) between n-pentane and DMSO was investigated as a contribution to understand the interaction between resveratrol and biomembranes. In order to determine the partition coefficient P* of resveratrol between pentane and DMSO, resveratrol ...

  5. Fat polygonal partitions with applications to visualization and embeddings

    Directory of Open Access Journals (Sweden)

    Mark de Berg

    2013-12-01

    Full Text Available Let T be a rooted and weighted tree, where the weight of any node is equal to the sum of the weights of its children. The popular Treemap algorithm visualizes such a tree as a hierarchical partition of a square into rectangles, where the area of the rectangle corresponding to any node in T is equal to the weight of that node. The aspect ratio of the rectangles in such a rectangular partition necessarily depends on the weights and can become arbitrarily high.We introduce a new hierarchical partition scheme, called a polygonal partition, which uses convex polygons rather than just rectangles. We present two methods for constructing polygonal partitions, both having guarantees on the worst-case aspect ratio of the constructed polygons; in particular, both methods guarantee a bound on the aspect ratio that is independent of the weights of the nodes.We also consider rectangular partitions with slack, where the areas of the rectangles may differ slightly from the weights of the corresponding nodes. We show that this makes it possible to obtain partitions with constant aspect ratio. This result generalizes to hyper-rectangular partitions in ℝd. We use these partitions with slack for embedding ultrametrics into d-dimensional Euclidean space:  we give a polylog(Δ-approximation algorithm for embedding n-point ultrametrics into ℝd with minimum distortion, where Δ denotes the spread of the metric. The previously best-known approximation ratio for this problem was polynomial in n. This is the first algorithm for embedding a non-trivial family of weighted-graph metrics into a space of constant dimension that achieves polylogarithmic approximation ratio.

  6. High Pressure/Temperature Metal Silicate Partitioning of Tungsten

    Science.gov (United States)

    Shofner, G. A.; Danielson, L.; Righter, K.; Campbell, A. J.

    2010-01-01

    The behavior of chemical elements during metal/silicate segregation and their resulting distribution in Earth's mantle and core provide insight into core formation processes. Experimental determination of partition coefficients allows calculations of element distributions that can be compared to accepted values of element abundances in the silicate (mantle) and metallic (core) portions of the Earth. Tungsten (W) is a moderately siderophile element and thus preferentially partitions into metal versus silicate under many planetary conditions. The partitioning behavior has been shown to vary with temperature, silicate composition, oxygen fugacity, and pressure. Most of the previous work on W partitioning has been conducted at 1-bar conditions or at relatively low pressures, i.e. pressure. Predictions based on extrapolation of existing data and parameterizations suggest an increased pressured dependence on metal/ silicate partitioning of W at higher pressures 5. However, the dependence on pressure is not as well constrained as T, fO2, and silicate composition. This poses a problem because proposed equilibration pressures for core formation range from 27 to 50 GPa, falling well outside the experimental range, therefore requiring exptrapolation of a parametereized model. Higher pressure data are needed to improve our understanding of W partitioning at these more extreme conditions.

  7. Transfer and partitioning of energy and mass through seafloor hydrothermal systems: comparative studies at the Ridge2000 Integrated Study Sites (ISS) (Invited)

    Science.gov (United States)

    Tivey, M. K.

    2010-12-01

    temperature-composition paths taken by fluids, and the extent to which some elements (e.g., Cu, Fe, Zn, Ba, S) are partitioned between deposits and plumes. Precipitation efficiency differs depending on the vigor of venting and fluid composition (e.g., pH), which (in part) determines the prevalence of black smoker activity versus flow through diffusers and flanges (e.g., review in Tivey, Oceanography, 2007). Quantification of this partitioning is further complicated by apparent differences in ages of accumulated deposits in different vent fields. An unknown at many vent fields is the length of time and duration of activity responsible for forming the existing deposits, and the extent to which large size is a result of efficient precipitation versus time. For biota, the different styles of fluid flow through the substrate and different parts of deposits affect thermal and chemical environments in plumes, as well as on, and just inside, deposit exteriors. As with our understanding of mass and energy transfer to the ocean, we can make significant advances in our understanding of this partitioning of energy and mass through comparative studies of hydrothermal systems in a diverse range of geologic settings (e.g., at the three Ridge2000 ISS).

  8. Optimization of the size and shape of the set-in nozzle for a PWR reactor pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Murtaza, Usman Tariq, E-mail: maniiut@yahoo.com; Javed Hyder, M., E-mail: hyder@pieas.edu.pk

    2015-04-01

    Highlights: • The size and shape of the set-in nozzle of the RPV have been optimized. • The optimized nozzle ensure the reduction of the mass around 198 kg per nozzle. • The mass of the RPV should be minimized for better fracture toughness. - Abstract: The objective of this research work is to optimize the size and shape of the set-in nozzle for a typical reactor pressure vessel (RPV) of a 300 MW pressurized water reactor. The analysis was performed by optimizing the four design variables which control the size and shape of the nozzle. These variables are inner radius of the nozzle, thickness of the nozzle, taper angle at the nozzle-cylinder intersection, and the point where taper of the nozzle starts from. It is concluded that the optimum design of the nozzle is the one that minimizes the two conflicting state variables, i.e., the stress intensity (Tresca yield criterion) and the mass of the RPV.

  9. Gas-particle phase partitioning and particle size distribution of chlorinated and brominated polycyclic aromatic hydrocarbons in haze.

    Science.gov (United States)

    Jin, Rong; Zheng, Minghui; Yang, Hongbo; Yang, Lili; Wu, Xiaolin; Xu, Yang; Liu, Guorui

    2017-12-01

    Chlorinated and brominated polycyclic aromatic hydrocarbons (Cl/Br-PAHs) are emerging semi-volatile organic pollutants in haze-associated particulate matter (PM). Their gas-particle phase partitioning and distribution among PM fractions have not been clarified. Clarification would increase understanding of atmospheric behavior and health risks of Cl/Br-PAHs. In this study, samples of the gas phase and 4 PM phases (aerodynamic diameters (d ae ) > 10 μm, 2.5-10 μm, 1.0-2.5 μm, and <1.0 μm) were collected simultaneously during haze events in Beijing and analyzed. Normalized histogram distribution indicated that the Cl/Br-PAHs tended to adhere to fine particles. Over 80% of the Cl-PAHs and 70% of the Br-PAHs were associated with fine PM (d ae  < 2.5 μm). The gas-particle phase partitioning and PM distribution of Cl/Br-PAHs when heating of buildings was required, which was associated with haze events, were obviously different from those when heating was not required. The relationship between the logarithmic geometric mean diameters of the Cl/Br-PAH congeners and reciprocal of the temperature (1/T) suggested that low air temperatures during the heating period could lead to high proportions of Cl/Br-PAHs in the fine particles. Increased coal burning during the heating period also contributed to high Cl/Br-PAH loads in the fine particles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Efficient Algorithms for Searching the Minimum Information Partition in Integrated Information Theory

    Science.gov (United States)

    Kitazono, Jun; Kanai, Ryota; Oizumi, Masafumi

    2018-03-01

    The ability to integrate information in the brain is considered to be an essential property for cognition and consciousness. Integrated Information Theory (IIT) hypothesizes that the amount of integrated information ($\\Phi$) in the brain is related to the level of consciousness. IIT proposes that to quantify information integration in a system as a whole, integrated information should be measured across the partition of the system at which information loss caused by partitioning is minimized, called the Minimum Information Partition (MIP). The computational cost for exhaustively searching for the MIP grows exponentially with system size, making it difficult to apply IIT to real neural data. It has been previously shown that if a measure of $\\Phi$ satisfies a mathematical property, submodularity, the MIP can be found in a polynomial order by an optimization algorithm. However, although the first version of $\\Phi$ is submodular, the later versions are not. In this study, we empirically explore to what extent the algorithm can be applied to the non-submodular measures of $\\Phi$ by evaluating the accuracy of the algorithm in simulated data and real neural data. We find that the algorithm identifies the MIP in a nearly perfect manner even for the non-submodular measures. Our results show that the algorithm allows us to measure $\\Phi$ in large systems within a practical amount of time.

  11. Enumerating set partitions according to the number of descents of ...

    Indian Academy of Sciences (India)

    ) according to the number of descents of size or more, where ≥ 1 is fixed. An explicit expression in terms of Stirling numbers of the second kind may be given for the total number of such descents in all the members of (,). We also ...

  12. Gas-liquid partitioning of halogenated volatile organic compounds in aqueous cyclodextrin solutions

    Energy Technology Data Exchange (ETDEWEB)

    Ondo, Daniel; Barankova, Eva [Department of Physical Chemistry, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic); Dohnal, Vladimir, E-mail: dohnalv@vscht.cz [Department of Physical Chemistry, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic)

    2011-08-15

    Highlights: > Binding of halogenated VOCs with cyclodextrins examined through g-l partitioning. > Complex stabilities reflect host-guest size matching and hydrophobic interaction. > Presence of halogens in the guest molecule stabilizes the binding. > Thermodynamic origin of the binding varies greatly among the systems studied. > Results obey the guest-CD global enthalpy-entropy compensation relationship. - Abstract: Gas-liquid partitioning coefficients (K{sub GL}) were measured for halogenated volatile organic compounds (VOCs), namely 1-chlorobutane, methoxyflurane, pentafluoropropan-1-ol, heptafluorobutan-1-ol, {alpha},{alpha},{alpha}-trifluorotoluene, and toluene in aqueous solutions of natural {alpha}-, {beta}-, and {gamma}-cyclodextrins (CDs) at temperatures from (273.35 to 326.35) K employing the techniques of headspace gas chromatography and inert gas stripping. The binding constants of the 1:1 inclusion complex formation between the VOCs and CDs were evaluated from the depression of the VOCs volatility as a function of CD concentration. The host-guest size matching and the hydrophobic interaction concept were used to rationalize the observed widely different affinity of the VOC-CD pairs to form the inclusion complex. The enthalpic and entropic component of the standard Gibbs free energy of complex formation as derived from the temperature dependence of the binding constant indicate the thermodynamic origin of the binding to vary greatly among the systems studied, but follow the global enthalpy-entropy compensation relationships reported previously in the literature.

  13. Analysis of Noise Mechanisms in Cell-Size Control.

    Science.gov (United States)

    Modi, Saurabh; Vargas-Garcia, Cesar Augusto; Ghusinga, Khem Raj; Singh, Abhyudai

    2017-06-06

    At the single-cell level, noise arises from multiple sources, such as inherent stochasticity of biomolecular processes, random partitioning of resources at division, and fluctuations in cellular growth rates. How these diverse noise mechanisms combine to drive variations in cell size within an isoclonal population is not well understood. Here, we investigate the contributions of different noise sources in well-known paradigms of cell-size control, such as adder (division occurs after adding a fixed size from birth), sizer (division occurs after reaching a size threshold), and timer (division occurs after a fixed time from birth). Analysis reveals that variation in cell size is most sensitive to errors in partitioning of volume among daughter cells, and not surprisingly, this process is well regulated among microbes. Moreover, depending on the dominant noise mechanism, different size-control strategies (or a combination of them) provide efficient buffering of size variations. We further explore mixer models of size control, where a timer phase precedes/follows an adder, as has been proposed in Caulobacter crescentus. Although mixing a timer and an adder can sometimes attenuate size variations, it invariably leads to higher-order moments growing unboundedly over time. This results in a power-law distribution for the cell size, with an exponent that depends inversely on the noise in the timer phase. Consistent with theory, we find evidence of power-law statistics in the tail of C. crescentus cell-size distribution, although there is a discrepancy between the observed power-law exponent and that predicted from the noise parameters. The discrepancy, however, is removed after data reveal that the size added by individual newborns in the adder phase itself exhibits power-law statistics. Taken together, this study provides key insights into the role of noise mechanisms in size homeostasis, and suggests an inextricable link between timer-based models of size control and

  14. Inference of Boundaries in Causal Sets

    OpenAIRE

    Cunningham, William

    2017-01-01

    We investigate the extrinsic geometry of causal sets in $(1+1)$-dimensional Minkowski spacetime. The properties of boundaries in an embedding space can be used not only to measure observables, but also to supplement the discrete action in the partition function via discretized Gibbons-Hawking-York boundary terms. We define several ways to represent a causal set using overlapping subsets, which then allows us to distinguish between null and non-null bounding hypersurfaces in an embedding space...

  15. Portfolio of automated trading systems: complexity and learning set size issues.

    Science.gov (United States)

    Raudys, Sarunas

    2013-03-01

    In this paper, we consider using profit/loss histories of multiple automated trading systems (ATSs) as N input variables in portfolio management. By means of multivariate statistical analysis and simulation studies, we analyze the influences of sample size (L) and input dimensionality on the accuracy of determining the portfolio weights. We find that degradation in portfolio performance due to inexact estimation of N means and N(N - 1)/2 correlations is proportional to N/L; however, estimation of N variances does not worsen the result. To reduce unhelpful sample size/dimensionality effects, we perform a clustering of N time series and split them into a small number of blocks. Each block is composed of mutually correlated ATSs. It generates an expert trading agent based on a nontrainable 1/N portfolio rule. To increase the diversity of the expert agents, we use training sets of different lengths for clustering. In the output of the portfolio management system, the regularized mean-variance framework-based fusion agent is developed in each walk-forward step of an out-of-sample portfolio validation experiment. Experiments with the real financial data (2003-2012) confirm the effectiveness of the suggested approach.

  16. Choosing the best partition of the output from a large-scale simulation

    Energy Technology Data Exchange (ETDEWEB)

    Challacombe, Chelsea Jordan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Casleton, Emily Michele [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-26

    Data partitioning becomes necessary when a large-scale simulation produces more data than can be feasibly stored. The goal is to partition the data, typically so that every element belongs to one and only one partition, and store summary information about the partition, either a representative value plus an estimate of the error or a distribution. Once the partitions are determined and the summary information stored, the raw data is discarded. This process can be performed in-situ; meaning while the simulation is running. When creating the partitions there are many decisions that researchers must make. For instance, how to determine once an adequate number of partitions have been created, how are the partitions created with respect to dividing the data, or how many variables should be considered simultaneously. In addition, decisions must be made for how to summarize the information within each partition. Because of the combinatorial number of possible ways to partition and summarize the data, a method of comparing the different possibilities will help guide researchers into choosing a good partitioning and summarization scheme for their application.

  17. Set size influences the relationship between ANS acuity and math performance: a result of different strategies?

    Science.gov (United States)

    Dietrich, Julia Felicitas; Nuerk, Hans-Christoph; Klein, Elise; Moeller, Korbinian; Huber, Stefan

    2017-08-29

    Previous research has proposed that the approximate number system (ANS) constitutes a building block for later mathematical abilities. Therefore, numerous studies investigated the relationship between ANS acuity and mathematical performance, but results are inconsistent. Properties of the experimental design have been discussed as a potential explanation of these inconsistencies. In the present study, we investigated the influence of set size and presentation duration on the association between non-symbolic magnitude comparison and math performance. Moreover, we focused on strategies reported as an explanation for these inconsistencies. In particular, we employed a non-symbolic magnitude comparison task and asked participants how they solved the task. We observed that set size was a significant moderator of the relationship between non-symbolic magnitude comparison and math performance, whereas presentation duration of the stimuli did not moderate this relationship. This supports the notion that specific design characteristics contribute to the inconsistent results. Moreover, participants reported different strategies including numerosity-based, visual, counting, calculation-based, and subitizing strategies. Frequencies of these strategies differed between different set sizes and presentation durations. However, we found no specific strategy, which alone predicted arithmetic performance, but when considering the frequency of all reported strategies, arithmetic performance could be predicted. Visual strategies made the largest contribution to this prediction. To conclude, the present findings suggest that different design characteristics contribute to the inconsistent findings regarding the relationship between non-symbolic magnitude comparison and mathematical performance by inducing different strategies and additional processes.

  18. Why partition nuclear waste

    International Nuclear Information System (INIS)

    Cohen, J.J.

    1976-01-01

    A cursory review of literature dealing with various separatory processes involved in the handling of high-level liquid nuclear waste discloses that, for the most part, discussion centers on separation procedures and methodology for handling the resulting fractions, particularly the actinide wastes. There appears to be relatively little discussion on the incentives or motivations for performing these separations in the first place. Discussion is often limited to the assumption that we must separate out ''long-term'' from our ''short-term'' management problems. This paper deals with that assumption and devotes primary attention to the question of ''why partition waste'' rather than the question of ''how to partition waste'' or ''what to do with the segregated waste.''

  19. Combinatorics and complexity of partition functions

    CERN Document Server

    Barvinok, Alexander

    2016-01-01

    Partition functions arise in combinatorics and related problems of statistical physics as they encode in a succinct way the combinatorial structure of complicated systems. The main focus of the book is on efficient ways to compute (approximate) various partition functions, such as permanents, hafnians and their higher-dimensional versions, graph and hypergraph matching polynomials, the independence polynomial of a graph and partition functions enumerating 0-1 and integer points in polyhedra, which allows one to make algorithmic advances in otherwise intractable problems. The book unifies various, often quite recent, results scattered in the literature, concentrating on the three main approaches: scaling, interpolation and correlation decay. The prerequisites include moderate amounts of real and complex analysis and linear algebra, making the book accessible to advanced math and physics undergraduates. .

  20. Structural partitioning of complex structures in the medium-frequency range. An application to an automotive vehicle

    Science.gov (United States)

    Kassem, M.; Soize, C.; Gagliardini, L.

    2011-02-01

    In a recent work [ Journal of Sound and Vibration 323 (2009) 849-863] the authors presented an energy-density field approach for the vibroacoustic analysis of complex structures in the low and medium frequency ranges. In this approach, a local vibroacoustic energy model as well as a simplification of this model were constructed. In this paper, firstly an extension of the previous theory is performed in order to include the case of general input forces and secondly, a structural partitioning methodology is presented along with a set of tools used for the construction of a partitioning. Finally, an application is presented for an automotive vehicle.

  1. The Concepts of Pseudo Compound Poisson and Partition Representations in Discrete Probability

    Directory of Open Access Journals (Sweden)

    Werner Hürlimann

    2015-01-01

    Full Text Available The mathematical/statistical concepts of pseudo compound Poisson and partition representations in discrete probability are reviewed and clarified. A combinatorial interpretation of the convolution of geometric distributions in terms of a variant of Newton’s identities is obtained. The practical use of the twofold convolution leads to an improved goodness-of-fit for a data set from automobile insurance that was up to now not fitted satisfactorily.

  2. Colour-independent partition functions in coloured vertex models

    Energy Technology Data Exchange (ETDEWEB)

    Foda, O., E-mail: omar.foda@unimelb.edu.au [Dept. of Mathematics and Statistics, University of Melbourne, Parkville, VIC 3010 (Australia); Wheeler, M., E-mail: mwheeler@lpthe.jussieu.fr [Laboratoire de Physique Théorique et Hautes Energies, CNRS UMR 7589 (France); Université Pierre et Marie Curie – Paris 6, 4 place Jussieu, 75252 Paris cedex 05 (France)

    2013-06-11

    We study lattice configurations related to S{sub n}, the scalar product of an off-shell state and an on-shell state in rational A{sub n} integrable vertex models, n∈{1,2}. The lattice lines are colourless and oriented. The state variables are n conserved colours that flow along the line orientations, but do not necessarily cover every bond in the lattice. Choosing boundary conditions such that the positions where the colours flow into the lattice are fixed, and where they flow out are summed over, we show that the partition functions of these configurations, with these boundary conditions, are n-independent. Our results extend to trigonometric A{sub n} models, and to all n. This n-independence explains, in vertex-model terms, results from recent studies of S{sub 2} (Caetano and Vieira, 2012, [1], Wheeler, (arXiv:1204.2089), [2]). Namely, 1.S{sub 2}, which depends on two sets of Bethe roots, {b_1} and {b_2}, and cannot (as far as we know) be expressed in single determinant form, degenerates in the limit {b_1}→∞, and/or {b_2}→∞, into a product of determinants, 2. Each of the latter determinants is an A{sub 1} vertex-model partition function.

  3. Colour-independent partition functions in coloured vertex models

    International Nuclear Information System (INIS)

    Foda, O.; Wheeler, M.

    2013-01-01

    We study lattice configurations related to S n , the scalar product of an off-shell state and an on-shell state in rational A n integrable vertex models, n∈{1,2}. The lattice lines are colourless and oriented. The state variables are n conserved colours that flow along the line orientations, but do not necessarily cover every bond in the lattice. Choosing boundary conditions such that the positions where the colours flow into the lattice are fixed, and where they flow out are summed over, we show that the partition functions of these configurations, with these boundary conditions, are n-independent. Our results extend to trigonometric A n models, and to all n. This n-independence explains, in vertex-model terms, results from recent studies of S 2 (Caetano and Vieira, 2012, [1], Wheeler, (arXiv:1204.2089), [2]). Namely, 1.S 2 , which depends on two sets of Bethe roots, {b 1 } and {b 2 }, and cannot (as far as we know) be expressed in single determinant form, degenerates in the limit {b 1 }→∞, and/or {b 2 }→∞, into a product of determinants, 2. Each of the latter determinants is an A 1 vertex-model partition function

  4. The influence of hydrogen bonding on partition coefficients

    Science.gov (United States)

    Borges, Nádia Melo; Kenny, Peter W.; Montanari, Carlos A.; Prokopczyk, Igor M.; Ribeiro, Jean F. R.; Rocha, Josmar R.; Sartori, Geraldo Rodrigues

    2017-02-01

    This Perspective explores how consideration of hydrogen bonding can be used to both predict and better understand partition coefficients. It is shown how polarity of both compounds and substructures can be estimated from measured alkane/water partition coefficients. When polarity is defined in this manner, hydrogen bond donors are typically less polar than hydrogen bond acceptors. Analysis of alkane/water partition coefficients in conjunction with molecular electrostatic potential calculations suggests that aromatic chloro substituents may be less lipophilic than is generally believed and that some of the effect of chloro-substitution stems from making the aromatic π-cloud less available to hydrogen bond donors. Relationships between polarity and calculated hydrogen bond basicity are derived for aromatic nitrogen and carbonyl oxygen. Aligned hydrogen bond acceptors appear to present special challenges for prediction of alkane/water partition coefficients and this may reflect `frustration' of solvation resulting from overlapping hydration spheres. It is also shown how calculated hydrogen bond basicity can be used to model the effect of aromatic aza-substitution on octanol/water partition coefficients.

  5. Compactified webs and domain wall partition functions

    Energy Technology Data Exchange (ETDEWEB)

    Shabbir, Khurram [Government College University, Department of Mathematics, Lahore (Pakistan)

    2017-04-15

    In this paper we use the topological vertex formalism to calculate a generalization of the ''domain wall'' partition function of M-strings. This generalization allows calculation of partition function of certain compactified webs using a simple gluing algorithm similar to M-strings case. (orig.)

  6. Structural analysis of the ParR/parC plasmid partition complex

    DEFF Research Database (Denmark)

    Møller-Jensen, Jakob; Ringgaard, Simon; Mercogliano, Christopher P

    2007-01-01

    Accurate DNA partition at cell division is vital to all living organisms. In bacteria, this process can involve partition loci, which are found on both chromosomes and plasmids. The initial step in Escherichia coli plasmid R1 partition involves the formation of a partition complex between the DNA...

  7. Interfacial thermodynamics and electrochemistry of protein partitioning in two-phase systems

    NARCIS (Netherlands)

    Fraaije, J.G.E.M.

    1987-01-01

    The subject of this thesis is protein partition between an aqueous salt solution and a surface or an apolair liquid and the concomitant co-partition of small ions. The extent of co-partitioning determines the charge regulation in the protein partitioning process.

    Chapters 2 and 3

  8. Partitioning of organochlorine pesticides from water to polyethylene passive samplers

    International Nuclear Information System (INIS)

    Hale, Sarah E.; Martin, Timothy J.; Goss, Kai-Uwe; Arp, Hans Peter H.; Werner, David

    2010-01-01

    The mass transfer rates and equilibrium partitioning behaviour of 14 diverse organochlorine pesticides (OCP) between water and polyethylene (PE) passive samplers, cut from custom made PE sheets and commercial polyethylene plastic bags, were quantified. Overall mass transfer coefficients, k O , estimated PE membrane diffusion coefficients, D PE , and PE-water partitioning coefficients, K PE-water, are reported. In addition, the partitioning of three polycyclic aromatic hydrocarbons (PAHs) from water to PE is quantified and compared with literature values. K PE-water values agreed mostly within a factor of two for both passive samplers and also with literature values for the reference PAHs. As PE is expected to exhibit similar sorption behaviour to long-chain alkanes, PE-water partitioning coefficients were compared to hexadecane-water partitioning coefficients estimated with the SPARC online calculator, COSMOtherm and a polyparameter linear free energy relationship based on the Abraham approach. The best correlation for all compounds tested was with COSMOtherm estimated hexadecane-water partitioning coefficients. - The partitioning of organochlorine pesticides between single phase polyethylene passive samplers and water is quantified.

  9. GASDRA: Galaxy Spectrum Dynamic Range Analysis for Photometric Redshift Filter Partition Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Vicente, J. de; Sanchez, E.; Sevilla, I.; Castilla, J.; Ponce, R.; Sanchez, F. J.

    2012-04-11

    The photometric redshift is an active area of research. It is becoming the preferred method for redshift measurement above spectroscopy one for large surveys. In these surveys, the requirement in redshift precision is relaxed in benefit of obtaining the measurements of large number of galaxies. One of the more relevant decisions to be taken in the design of a photometric redshift experiment is the number of filters since it affects deeply to the precision and survey time. Currently, there is not a clear method for evaluating the impact in both precision and exposure time of a determined filter partition set and usually it is determined by detailed simulations on the behavior of photo-z algorithms. In this note we describe GASDRA, a new method for extracting the minimal signal to noise requirement, depending on the number of filters needed for preserving the filtered spectrum shape, and hence to make feasible the spectrum identification. The application of this requirement guaranties a determined precision in the spectrum measurement. Although it cannot be translated directly to absolute photometric redshift error, it does provide a method for comparing the relative precision achieved in the spectrum representation by different sets of filters. We foresee that this relative precision is close related to photo-z error. In addition, we can evaluate the impact in the exposure time of any filter partition set with respect to other. (Author) 11 refs.

  10. GASDRA: Galaxy Spectrum Dynamic Range Analysis for Photometric Redshift Filter Partition Optimization

    International Nuclear Information System (INIS)

    Vicente, J. de; Sanchez, E.; Sevilla, I.; Castilla, J.; Ponce, R.; Sanchez, F. J.

    2012-01-01

    The photometric redshift is an active area of research. It is becoming the preferred method for redshift measurement above spectroscopy one for large surveys. In these surveys, the requirement in redshift precision is relaxed in benefit of obtaining the measurements of large number of galaxies. One of the more relevant decisions to be taken in the design of a photometric redshift experiment is the number of filters since it affects deeply to the precision and survey time. Currently, there is not a clear method for evaluating the impact in both precision and exposure time of a determined filter partition set and usually it is determined by detailed simulations on the behavior of photo-z algorithms. In this note we describe GASDRA, a new method for extracting the minimal signal to noise requirement, depending on the number of filters needed for preserving the filtered spectrum shape, and hence to make feasible the spectrum identification. The application of this requirement guaranties a determined precision in the spectrum measurement. Although it cannot be translated directly to absolute photometric redshift error, it does provide a method for comparing the relative precision achieved in the spectrum representation by different sets of filters. We foresee that this relative precision is close related to photo-z error. In addition, we can evaluate the impact in the exposure time of any filter partition set with respect to other. (Author) 11 refs.

  11. Time and Space Partitioning the EagleEye Reference Misson

    Science.gov (United States)

    Bos, Victor; Mendham, Peter; Kauppinen, Panu; Holsti, Niklas; Crespo, Alfons; Masmano, Miguel; de la Puente, Juan A.; Zamorano, Juan

    2013-08-01

    We discuss experiences gained by porting a Software Validation Facility (SVF) and a satellite Central Software (CSW) to a platform with support for Time and Space Partitioning (TSP). The SVF and CSW are part of the EagleEye Reference mission of the European Space Agency (ESA). As a reference mission, EagleEye is a perfect candidate to evaluate practical aspects of developing satellite CSW for and on TSP platforms. The specific TSP platform we used consists of a simulated LEON3 CPU controlled by the XtratuM separation micro-kernel. On top of this, we run five separate partitions. Each partition runs its own real-time operating system or Ada run-time kernel, which in turn are running the application software of the CSW. We describe issues related to partitioning; inter-partition communication; scheduling; I/O; and fault-detection, isolation, and recovery (FDIR).

  12. Prediction of Partition Coefficients of Organic Compounds for SPME/PDMS

    OpenAIRE

    Liao Hsuan-Yu; Huang Miao-Ling; Lu Yu-Ting; Chao Keh-Ping

    2016-01-01

    The partition coefficients of 51 organic compounds between SPME/PDMS and gas were compiled from the literature sources in this study. The effect of physicochemical properties and descriptors on the partitioning process of partition coefficients was explicated by the correlation analysis. The PDMS-gas partition coefficients were well correlated to the molecular weight of organic compounds (r = 0.832, p < 0.05). An empirical model, consisting of the molecular weight and the polarizability, was ...

  13. Construction of Scaling Partitions of Unity

    Directory of Open Access Journals (Sweden)

    Ole Christensen

    2017-11-01

    Full Text Available Partitions of unity in ℝd formed by (matrix scales of a fixed function appear in many parts of harmonic analysis, e.g., wavelet analysis and the analysis of Triebel-Lizorkin spaces. We give a simple characterization of the functions and matrices yielding such a partition of unity. For expanding matrices, the characterization leads to easy ways of constructing appropriate functions with attractive properties like high regularity and small support. We also discuss a class of integral transforms that map functions having the partition of unity property to functions with the same property. The one-dimensional version of the transform allows a direct definition of a class of nonuniform splines with properties that are parallel to those of the classical B-splines. The results are illustrated with the construction of dual pairs of wavelet frames.

  14. Application of radial basis function neural network to predict soil sorption partition coefficient using topological descriptors.

    Science.gov (United States)

    Sabour, Mohammad Reza; Moftakhari Anasori Movahed, Saman

    2017-02-01

    The soil sorption partition coefficient logK oc is an indispensable parameter that can be used in assessing the environmental risk of organic chemicals. In order to predict soil sorption partition coefficient for different and even unknown compounds in a fast and accurate manner, a radial basis function neural network (RBFNN) model was developed. Eight topological descriptors of 800 organic compounds were used as inputs of the model. These 800 organic compounds were chosen from a large and very diverse data set. Generalized Regression Neural Network (GRNN) was utilized as the function in this neural network model due to its capability to adapt very quickly. Hence, it can be used to predict logK oc for new chemicals, as well. Out of total data set, 560 organic compounds were used for training and 240 to test efficiency of the model. The obtained results indicate that the model performance is very well. The correlation coefficients (R2) for training and test sets were 0.995 and 0.933, respectively. The root-mean square errors (RMSE) were 0.2321 for training set and 0.413 for test set. As the results for both training and test set are extremely satisfactory, the proposed neural network model can be employed not only to predict logK oc of known compounds, but also to be adaptive for prediction of this value precisely for new products that enter the market each year. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Probabilistic Decision Based Block Partitioning for Future Video Coding

    KAUST Repository

    Wang, Zhao

    2017-11-29

    In the latest Joint Video Exploration Team development, the quadtree plus binary tree (QTBT) block partitioning structure has been proposed for future video coding. Compared to the traditional quadtree structure of High Efficiency Video Coding (HEVC) standard, QTBT provides more flexible patterns for splitting the blocks, which results in dramatically increased combinations of block partitions and high computational complexity. In view of this, a confidence interval based early termination (CIET) scheme is proposed for QTBT to identify the unnecessary partition modes in the sense of rate-distortion (RD) optimization. In particular, a RD model is established to predict the RD cost of each partition pattern without the full encoding process. Subsequently, the mode decision problem is casted into a probabilistic framework to select the final partition based on the confidence interval decision strategy. Experimental results show that the proposed CIET algorithm can speed up QTBT block partitioning structure by reducing 54.7% encoding time with only 1.12% increase in terms of bit rate. Moreover, the proposed scheme performs consistently well for the high resolution sequences, of which the video coding efficiency is crucial in real applications.

  16. Development of the four group partitioning process at JAERI

    International Nuclear Information System (INIS)

    Kubota, Masumitsu; Morita, Yasuji; Yamaguchi, Isoo; Yamagishi, Isao; Fujiwara, T.; Watanabe, Masayuki; Mizoguchi, Kenichi; Tatsugae, Ryozo

    1999-01-01

    At JAERI, development of a partitioning method started about 24 years ago. From 1973 to 1984, a partitioning process was developed for separating elements in HLLW into 3 groups; TRU, Sr-Cs and others. The partitioning process consisted of three steps; solvent extraction of U and Pu with TBP, solvent extraction of Am and Cm with DIDPA, and adsorption of Sr and Cs with inorganic ion exchangers. The process was demonstrated with real HLLW. Since 1985, a four group partitioning process has been developed, in which a step for separating the Tc-PGM group was developed in addition to the three group separation. Effective methods for separating TRU, especially Np, and Tc have been developed. In this paper, the flow sheet of the four group partitioning and the results of tests with simulated and real HLLW in NUCEF hot-cell are shown. (J.P.N.)

  17. The influence of spatial grain size on the suitability of the higher-taxon approach in continental priority-setting

    DEFF Research Database (Denmark)

    Larsen, Frank Wugt; Rahbek, Carsten

    2005-01-01

    The higher-taxon approach may provide a pragmatic surrogate for the rapid identification of priority areas for conservation. To date, no continent-wide study has examined the use of higher-taxon data to identify complementarity-based networks of priority areas, nor has the influence of spatial gr...... grain size been assessed. We used data obtained from 939 sub-Saharan mammals to analyse the performance of higher-taxon data for continental priority-setting and to assess the influence of spatial grain sizes in terms of the size of selection units (1°× 1°, 2°× 2° and 4°× 4° latitudinal...... as effectively as species-based priority areas, genus-based areas perform considerably less effectively than species-based areas for the 1° and 2° grain size. Thus, our results favour the higher-taxon approach for continental priority-setting only when large grain sizes (= 4°) are used.......The higher-taxon approach may provide a pragmatic surrogate for the rapid identification of priority areas for conservation. To date, no continent-wide study has examined the use of higher-taxon data to identify complementarity-based networks of priority areas, nor has the influence of spatial...

  18. Chaos synchronization basing on symbolic dynamics with nongenerating partition.

    Science.gov (United States)

    Wang, Xingyuan; Wang, Mogei; Liu, Zhenzhen

    2009-06-01

    Using symbolic dynamics and information theory, we study the information transmission needed for synchronizing unidirectionally coupled oscillators. It is found that when sustaining chaos synchronization with nongenerating partition, the synchronization error will be larger than a critical value, although the required coupled channel capacity can be smaller than the case of using a generating partition. Then we show that no matter whether a generating or nongenerating partition is in use, a high-quality detector can guarantee the lead of the response oscillator, while the lag responding can make up the low precision of the detector. A practicable synchronization scheme basing on a nongenerating partition is also proposed in this paper.

  19. The Partition of Multi-Resolution LOD Based on Qtm

    Science.gov (United States)

    Hou, M.-L.; Xing, H.-Q.; Zhao, X.-S.; Chen, J.

    2011-08-01

    The partition hierarch of Quaternary Triangular Mesh (QTM) determine the accuracy of spatial analysis and application based on QTM. In order to resolve the problem that the partition hierarch of QTM is limited by the level of the computer hardware, the new method that Multi- Resolution LOD (Level of Details) based on QTM will be discussed in this paper. This method can make the resolution of the cells varying with the viewpoint position by partitioning the cells of QTM, selecting the particular area according to the viewpoint; dealing with the cracks caused by different subdivisions, it satisfies the request of unlimited partition in part.

  20. THE PARTITION OF MULTI-RESOLUTION LOD BASED ON QTM

    Directory of Open Access Journals (Sweden)

    M.-L. Hou

    2012-08-01

    Full Text Available The partition hierarch of Quaternary Triangular Mesh (QTM determine the accuracy of spatial analysis and application based on QTM. In order to resolve the problem that the partition hierarch of QTM is limited by the level of the computer hardware, the new method that Multi- Resolution LOD (Level of Details based on QTM will be discussed in this paper. This method can make the resolution of the cells varying with the viewpoint position by partitioning the cells of QTM, selecting the particular area according to the viewpoint; dealing with the cracks caused by different subdivisions, it satisfies the request of unlimited partition in part.

  1. LHCb: Optimising query execution time in LHCb Bookkeeping System using partition pruning and partition wise joins

    CERN Multimedia

    Mathe, Z

    2013-01-01

    The LHCb experiment produces a huge amount of data which has associated metadata such as run number, data taking condition (detector status when the data was taken), simulation condition, etc. The data are stored in files, replicated on the Computing Grid around the world. The LHCb Bookkeeping System provides methods for retrieving datasets based on their metadata. The metadata is stored in a hybrid database model, which is a mixture of Relational and Hierarchical database models and is based on the Oracle Relational Database Management System (RDBMS). The database access has to be reliable and fast. In order to achieve a high timing performance, the tables are partitioned and the queries are executed in parallel. When we store large amounts of data the partition pruning is essential for database performance, because it reduces the amount of data retrieved from the disk and optimises the resource utilisation. This research presented here is focusing on the extended composite partitioning strategy such as rang...

  2. Open software tools for eddy covariance flux partitioning

    Science.gov (United States)

    Agro-ecosystem management and assessment will benefit greatly from the development of reliable techniques for partitioning evapotranspiration (ET) into evaporation (E) and transpiration (T). Among other activities, flux partitioning can aid in evaluating consumptive vs. non-consumptive agricultural...

  3. Partitioning a macroscopic system into independent subsystems

    Science.gov (United States)

    Delle Site, Luigi; Ciccotti, Giovanni; Hartmann, Carsten

    2017-08-01

    We discuss the problem of partitioning a macroscopic system into a collection of independent subsystems. The partitioning of a system into replica-like subsystems is nowadays a subject of major interest in several fields of theoretical and applied physics. The thermodynamic approach currently favoured by practitioners is based on a phenomenological definition of an interface energy associated with the partition, due to a lack of easily computable expressions for a microscopic (i.e. particle-based) interface energy. In this article, we outline a general approach to derive sharp and computable bounds for the interface free energy in terms of microscopic statistical quantities. We discuss potential applications in nanothermodynamics and outline possible future directions.

  4. Using Patient Demographics and Statistical Modeling to Predict Knee Tibia Component Sizing in Total Knee Arthroplasty.

    Science.gov (United States)

    Ren, Anna N; Neher, Robert E; Bell, Tyler; Grimm, James

    2018-06-01

    Preoperative planning is important to achieve successful implantation in primary total knee arthroplasty (TKA). However, traditional TKA templating techniques are not accurate enough to predict the component size to a very close range. With the goal of developing a general predictive statistical model using patient demographic information, ordinal logistic regression was applied to build a proportional odds model to predict the tibia component size. The study retrospectively collected the data of 1992 primary Persona Knee System TKA procedures. Of them, 199 procedures were randomly selected as testing data and the rest of the data were randomly partitioned between model training data and model evaluation data with a ratio of 7:3. Different models were trained and evaluated on the training and validation data sets after data exploration. The final model had patient gender, age, weight, and height as independent variables and predicted the tibia size within 1 size difference 96% of the time on the validation data, 94% of the time on the testing data, and 92% on a prospective cadaver data set. The study results indicated the statistical model built by ordinal logistic regression can increase the accuracy of tibia sizing information for Persona Knee preoperative templating. This research shows statistical modeling may be used with radiographs to dramatically enhance the templating accuracy, efficiency, and quality. In general, this methodology can be applied to other TKA products when the data are applicable. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Yoink: An interaction-based partitioning API.

    Science.gov (United States)

    Zheng, Min; Waller, Mark P

    2018-05-15

    Herein, we describe the implementation details of our interaction-based partitioning API (application programming interface) called Yoink for QM/MM modeling and fragment-based quantum chemistry studies. Interactions are detected by computing density descriptors such as reduced density gradient, density overlap regions indicator, and single exponential decay detector. Only molecules having an interaction with a user-definable QM core are added to the QM region of a hybrid QM/MM calculation. Moreover, a set of molecule pairs having density-based interactions within a molecular system can be computed in Yoink, and an interaction graph can then be constructed. Standard graph clustering methods can then be applied to construct fragments for further quantum chemical calculations. The Yoink API is licensed under Apache 2.0 and can be accessed via yoink.wallerlab.org. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  6. Off-diagonal series expansion for quantum partition functions

    Science.gov (United States)

    Hen, Itay

    2018-05-01

    We derive an integral-free thermodynamic perturbation series expansion for quantum partition functions which enables an analytical term-by-term calculation of the series. The expansion is carried out around the partition function of the classical component of the Hamiltonian with the expansion parameter being the strength of the off-diagonal, or quantum, portion. To demonstrate the usefulness of the technique we analytically compute to third order the partition functions of the 1D Ising model with longitudinal and transverse fields, and the quantum 1D Heisenberg model.

  7. Experimental constraints on partitioning and zoning of phosphorus in igneous olivine

    Science.gov (United States)

    Ersoy, Ö.; Nikogosian, I.; Mason, P. R. D.; Van Westrenen, W.; van Bergen, M.

    2017-12-01

    Fast diffusion and homogenization of divalent cations hamper the preservation of original chemical compositions and zoning patterns of igneous olivine phenocrysts. Sluggish intracrystalline diffusion of phosphorus in igneous olivine on the other hand allows the complex zoning patterns to be retained, making it a crucial element for reconstruction of cooling histories and evolution of the host magma. Crystallization rate variations, diffusion controlled growth or compositional controls on melt-mineral partitioning have been put forward as mechanisms controlling zoning of igneous olivine in phosphorus. Here, we investigate partitioning and zoning of phosphorus in igneous olivines by a comparison of natural and experimentally grown olivines. We explore the importance of variable degrees of undercooling and cooling rates in crystallizing melt (M1) with a starting composition equivalent to that of an Italian high-potassium basalt (Tliq=1274 °C). We examine the extent of compositional control on partitioning by varying the amount of alkali enrichment in starting compositions that are otherwise equivalent to melt M1. Olivine crystallization experiments were conducted in rhenium capsules suspended in a vertical 1-atm gas-mixing furnace at Vrije Universiteit Amsterdam (VUA) with fO2 buffered at 1.4 to 1.7 log units below the Ni-NiO buffer. Sets of dynamic crystallization experiments with various degrees of undercooling and controlled cooling rate experiments with varying cooling rates were performed. We compare the results with our extensive EPMA and LA-ICPMS dataset on olivines from Italian K-rich mafic lavas and olivine hosted primitive melt inclusions (MIs). Phosphorus concentrations in the natural olivines reach 435 ppm P and MIs contain up to 2.2 wt.% P2O5. High resolution (1-4 µm per pixel) element maps show both fine oscillatory, patchy and large scale sector zoning in P, uncorrelated with zoning in any other element. The MIs are almost always found in P-poor zones

  8. On an edge partition and root graphs of some classes of line graphs

    Directory of Open Access Journals (Sweden)

    K Pravas

    2017-04-01

    Full Text Available The Gallai and the anti-Gallai graphs of a graph $G$ are complementary pairs of spanning subgraphs of the line graph of $G$. In this paper we find some structural relations between these graph classes by finding a partition of the edge set of the line graph of a graph $G$ into the edge sets of the Gallai and anti-Gallai graphs of $G$. Based on this, an optimal algorithm to find the root graph of a line graph is obtained. Moreover, root graphs of diameter-maximal, distance-hereditary, Ptolemaic and chordal graphs are also discussed.

  9. Trophic niche partitioning between two native and two exotic carnivores in SW Portugal

    Directory of Open Access Journals (Sweden)

    M. J. Santos

    2007-05-01

    Full Text Available The introduction of exotic species is one of the most pervasive consequences of the increased human mobility. The most known negative effects are the decrease or extinction of natives. The common-genet, Genetta genetta, and the Egyptian mongoose, Herpestes ichneumon, were introduced in the Iberian Peninsula in the 15th and 19th centuries, respectively. The competitive exclusion principle defines that two ecologically similar species cannot coexist. Thus, some degree of partitioning has to occur in species realized niche, which can occur at the trophic level. To test this hypothesis of partitioning we compared the diet of these two exotic species with that of two native species (stone marten, Martes foina, and red fox, Vulpes vulpes. The results show a high degree of overlap (>45% between the diets of species similar in their feeding strategies (arboreal and ground feeding. Nonetheless, at the finer scale of prey consumed at the species level some differences are found between the native and exotic species. These results suggest that if coexistence is due to trophic niche partitioning it only occurs at the level of the consumed species. However, coexistence may also be due to a combination of different strategies (home-range size, time and space use that structured the different realized niches of each species.

  10. Modeling water and hydrogen networks with partitioning regeneration units

    Directory of Open Access Journals (Sweden)

    W.M. Shehata

    2015-03-01

    Full Text Available Strict environment regulations in chemical and refinery industries lead to minimize resource consumption by designing utility networks within industrial process plants. The present study proposed a superstructure based optimization model for the synthesis of water and hydrogen networks with partitioning regenerators without mixing the regenerated sources. This method determines the number of partitioning regenerators needed for the regeneration of the sources. The number of the regenerators is based on the number of sources required to be treated for recovery. Each source is regenerated in an individual partitioning regenerator. Multiple regeneration systems can be employed to achieve minimum flowrate and costs. The formulation is linear in the regenerator balance equations. The optimized model is applied for two systems, partitioning regeneration systems of the fixed outlet impurity concentration and partitioning regeneration systems of the fixed impurity load removal ratio (RR for water and hydrogen networks. Several case studies from the literature are solved to illustrate the ease and applicability of the proposed method.

  11. A layer model of ethanol partitioning into lipid membranes.

    Science.gov (United States)

    Nizza, David T; Gawrisch, Klaus

    2009-06-01

    The effect of membrane composition on ethanol partitioning into lipid bilayers was assessed by headspace gas chromatography. A series of model membranes with different compositions have been investigated. Membranes were exposed to a physiological ethanol concentration of 20 mmol/l. The concentration of membranes was 20 wt% which roughly corresponds to values found in tissue. Partitioning depended on the chemical nature of polar groups at the lipid/water interface. Compared to phosphatidylcholine, lipids with headgroups containing phosphatidylglycerol, phosphatidylserine, and sphingomyelin showed enhanced partitioning while headgroups containing phosphatidylethanolamine resulted in a lower partition coefficient. The molar partition coefficient was independent of a membrane's hydrophobic volume. This observation is in agreement with our previously published NMR results which showed that ethanol resides almost exclusively within the membrane/water interface. At an ethanol concentration of 20 mmol/l in water, ethanol concentrations at the lipid/water interface are in the range from 30-15 mmol/l, corresponding to one ethanol molecule per 100-200 lipids.

  12. Dominant partition method. [based on a wave function formalism

    Science.gov (United States)

    Dixon, R. M.; Redish, E. F.

    1979-01-01

    By use of the L'Huillier, Redish, and Tandy (LRT) wave function formalism, a partially connected method, the dominant partition method (DPM) is developed for obtaining few body reductions of the many body problem in the LRT and Bencze, Redish, and Sloan (BRS) formalisms. The DPM maps the many body problem to a fewer body one by using the criterion that the truncated formalism must be such that consistency with the full Schroedinger equation is preserved. The DPM is based on a class of new forms for the irreducible cluster potential, which is introduced in the LRT formalism. Connectivity is maintained with respect to all partitions containing a given partition, which is referred to as the dominant partition. Degrees of freedom corresponding to the breakup of one or more of the clusters of the dominant partition are treated in a disconnected manner. This approach for simplifying the complicated BRS equations is appropriate for physical problems where a few body reaction mechanism prevails.

  13. Vertical partitioning of relational OLTP databases using integer programming

    DEFF Research Database (Denmark)

    Amossen, Rasmus Resen

    2010-01-01

    A way to optimize performance of relational row store databases is to reduce the row widths by vertically partition- ing tables into table fractions in order to minimize the number of irrelevant columns/attributes read by each transaction. This pa- per considers vertical partitioning algorithms...... for relational row- store OLTP databases with an H-store-like architecture, meaning that we would like to maximize the number of single-sited transactions. We present a model for the vertical partitioning problem that, given a schema together with a vertical partitioning and a workload, estimates the costs...... applied to the TPC-C benchmark and the heuristic is shown to obtain solutions with costs close to the ones found using the quadratic program....

  14. Metric Structures on Fibered Manifolds Through Partitions of Unity

    Directory of Open Access Journals (Sweden)

    Hulya Kadioglu

    2016-05-01

    Full Text Available The notion of partitions of unity is extremely useful as it allows one to extend local constructions on Euclidean patches to global ones. It is widely used in many fields in mathematics. Therefore, prolongation of this useful tool to another manifold may help constructing many geometric structures. In this paper, we construct a partition of unity on a fiber bundle by using a given partition of unity on the base manifold. On the other hand we show that the converse is also possible if it is a vector bundle. As an application, we define a Riemannian metric on the fiber bundle by using induced partition of unity on the fiber bundle.

  15. Scanning Auger microscopy study of lanthanum partitioning in sphene-based glass-ceramics

    International Nuclear Information System (INIS)

    Hocking, W.H.; Hayward, P.J.; Watson, D.G.; Allen, G.C.

    1984-01-01

    Glass-ceramics are being investigated as possible hosts for the radioactive wastes that would result from recycling irradiated nuclear fuels. The partitioning of lanthanum in sphene-based glass-ceramics has been studied by scanning Auger electron microscopy for lanthanum concentrations from 0.2 to 2.0 mol.%. Sphene crystals (CaTiSiO 5 ) were located in the silica-rich glass matrix by recording digital Auger images of the calcium and titanium distributions. The sphene crystals were typically 0.5 to 5 μm in size and occupied approximately 40% of the total specimen volume. Auger spot analyses revealed that lanthanum was strongly partitioned into the sphene phase of phosphorus-free glass-ceramics; however, when a small amount of phosphorus was included in the glass-ceramic composition as a crystal nucleating agent, the lanthanum was concentrated in a third minor phase which also contained calcium, phosphorus and oxygen. Chemical shift effects in the Auger spectra of silicon, titanium and phosphorus showed evidence for electron-stimulated desorption of oxygen. (author)

  16. setsApp for Cytoscape: Set operations for Cytoscape Nodes and Edges [v2; ref status: indexed, http://f1000r.es/5lz

    Directory of Open Access Journals (Sweden)

    John H. Morris

    2015-08-01

    Full Text Available setsApp (http://apps.cytoscape.org/apps/setsapp is a relatively simple Cytoscape 3 app for users to handle groups of nodes and/or edges. It supports several important biological workflows and enables various set operations. setsApp provides basic tools to create sets of nodes or edges, import or export sets, and perform standard set operations (union, difference, intersection on those sets. Automatic set partitioning and layout functions are also provided. The sets functionality is also exposed to users and app developers in the form of a set of commands that can be used for scripting purposes or integrated in other Cytoscape apps.

  17. Actinide and fission product partitioning and transmutation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    The fourth international information exchange meeting on actinide and fission product partitioning and transmutation, took place in Mito City in Japan, on 111-13 September 1996. The proceedings are presented in six sessions: the major programmes and international cooperation, the partitioning and transmutation programs, feasibility studies, particular separation processes, the accelerator driven transmutation, and the chemistry of the fuel cycle. (A.L.B.)

  18. VLSI PARTITIONING ALGORITHM WITH ADAPTIVE CONTROL PARAMETER

    Directory of Open Access Journals (Sweden)

    P. N. Filippenko

    2013-03-01

    Full Text Available The article deals with the problem of very large-scale integration circuit partitioning. A graph is selected as a mathematical model describing integrated circuit. Modification of ant colony optimization algorithm is presented, which is used to solve graph partitioning problem. Ant colony optimization algorithm is an optimization method based on the principles of self-organization and other useful features of the ants’ behavior. The proposed search system is based on ant colony optimization algorithm with the improved method of the initial distribution and dynamic adjustment of the control search parameters. The experimental results and performance comparison show that the proposed method of very large-scale integration circuit partitioning provides the better search performance over other well known algorithms.

  19. Summer co-existence of small-sized cyprinid and percid individuals in natural and impounded stretches of a lowland river: food niche partitioning among fishes.

    Science.gov (United States)

    Lik, J; Dukowska, M; Grzybkowska, M; Leszczyńska, J

    2017-04-01

    Due to changes of discharge regime downstream of a dam reservoir, an alluvial natural stretch of the Warta River changed to a macrophyte-dominated ecosystem. Large patches of submersed, aquatic macrophytes appeared in summer and their effect is analysed in this study. These patches contained enriched macroinvertebrate assemblages (epiphyton and benthos) and they were refuge for both zooplankton and young fishes released from the reservoir. Despite these altered conditions in this stretch, roach Rutilus rutilus, perch Perca fluviatilis and ruffe Gymnocephalus cernua dominated, as they did in the natural backwater. Fishes were sampled every 2 weeks from June to August, together with their food resources to assess the partitioning of the diet among small individuals of the three species in both stretches (the natural and affected ones). The aim of the analysis was to answer how animal food associated with water plants was partitioned between the species. In both stretches, G. cernua were primarily benthivorous, but epiphytic fauna, zooplankton and large-sized benthic chironomid larvae replaced lack of many large, benthic insects in the tailwater. Levins' food breath index decreased from 0·36 in the backwater to 0·29 in the tailwater. An opposite trend was observed for P. fluviatilis occurring among macrophytes. Perca fluviatilis were competitors of R. rutilus and took food not only in or on the river bed, but also in the water column. They ate zooplankton and epiphytic fauna and Levins' index increased from 0·32 to 0·44 in the tailwater. Rutilus rutilus fed on adult insects, algae and plant fragments in the natural stretch. In the tailwater, these food types were chiefly complemented by zooplankton. Despite this, the niche breadth of R. rutilus was similar at the two sites. Abundance of food associated with the macrophytes appeared to facilitate cohabitation in the abundant fish populations, but P. fluviatilis appeared to benefit the most in the altered river

  20. Generalization of some hidden subgroup algorithms for input sets of arbitrary size

    Science.gov (United States)

    Poslu, Damla; Say, A. C. Cem

    2006-05-01

    We consider the problem of generalizing some quantum algorithms so that they will work on input domains whose cardinalities are not necessarily powers of two. When analyzing the algorithms we assume that generating superpositions of arbitrary subsets of basis states whose cardinalities are not necessarily powers of two perfectly is possible. We have taken Ballhysa's model as a template and have extended it to Chi, Kim and Lee's generalizations of the Deutsch-Jozsa algorithm and to Simon's algorithm. With perfectly equal superpositions of input sets of arbitrary size, Chi, Kim and Lee's generalized Deutsch-Jozsa algorithms, both for evenly-distributed and evenly-balanced functions, worked with one-sided error property. For Simon's algorithm the success probability of the generalized algorithm is the same as that of the original for input sets of arbitrary cardinalities with equiprobable superpositions, since the property that the measured strings are all those which have dot product zero with the string we search, for the case where the function is 2-to-1, is not lost.

  1. Correlations for the partition behavior of proteins in aqueous two-phase systems

    DEFF Research Database (Denmark)

    Schmidt, A.S.; Andrews, B.A.; Asenjo, J.A.

    1996-01-01

    to its high hydrophilicity. In the case of subtilisin and trypsin inhibitor, their high concentrations in the top phase were due to their hydrophobic nature (hydrophobic interaction with PEG) and small size (negligible steric exclusion). The maximum concentration in the bottom phase for trypsin inhibitor...... of the overall protein concentration, by the ratio between the ''saturation'' equations of the two individual phases. Better correlations were obtained when an empirical sigmoidal Boltzmann equation was fitted to the data, since in virtually all cases the partition coefficient is constant at low protein...

  2. Experimental investigation on the influence of instrument settings on pixel size and nonlinearity in SEM image formation

    DEFF Research Database (Denmark)

    Carli, Lorenzo; Genta, Gianfranco; Cantatore, Angela

    2010-01-01

    The work deals with an experimental investigation on the influence of three Scanning Electron Microscope (SEM) instrument settings, accelerating voltage, spot size and magnification, on the image formation process. Pixel size and nonlinearity were chosen as output parameters related to image...... quality and resolution. A silicon grating calibrated artifact was employed to investigate qualitatively and quantitatively, through a designed experiment approach, the parameters relevance. SEM magnification was found to account by far for the largest contribution on both parameters under consideration...

  3. 10 Management Controller for Time and Space Partitioning Architectures

    Science.gov (United States)

    Lachaize, Jerome; Deredempt, Marie-Helene; Galizzi, Julien

    2015-09-01

    The Integrated Modular Avionics (IMA) has been industrialized in aeronautical domain to enable the independent qualification of different application softwares from different suppliers on the same generic computer, this latter computer being a single terminal in a deterministic network. This concept allowed to distribute efficiently and transparently the different applications across the network, sizing accurately the HW equipments to embed on the aircraft, through the configuration of the virtual computers and the virtual network. , This concept has been studied for space domain and requirements issued [D04],[D05]. Experiments in the space domain have been done, for the computer level, through ESA and CNES initiatives [D02] [D03]. One possible IMA implementation may use Time and Space Partitioning (TSP) technology. Studies on Time and Space Partitioning [D02] for controlling resources access such as CPU and memories and studies on hardware/software interface standardization [D01] showed that for space domain technologies where I/O components (or IP) do not cover advanced features such as buffering, descriptors or virtualization, CPU overhead in terms of performances is mainly due to shared interface management in the execution platform, and to the high frequency of I/O accesses, these latter leading to an important number of context switches. This paper will present a solution to reduce this execution overhead with an open, modular and configurable controller.

  4. Skeletonization and Partitioning of Digital Images Using Discrete Morse Theory.

    Science.gov (United States)

    Delgado-Friedrichs, Olaf; Robins, Vanessa; Sheppard, Adrian

    2015-03-01

    We show how discrete Morse theory provides a rigorous and unifying foundation for defining skeletons and partitions of grayscale digital images. We model a grayscale image as a cubical complex with a real-valued function defined on its vertices (the voxel values). This function is extended to a discrete gradient vector field using the algorithm presented in Robins, Wood, Sheppard TPAMI 33:1646 (2011). In the current paper we define basins (the building blocks of a partition) and segments of the skeleton using the stable and unstable sets associated with critical cells. The natural connection between Morse theory and homology allows us to prove the topological validity of these constructions; for example, that the skeleton is homotopic to the initial object. We simplify the basins and skeletons via Morse-theoretic cancellation of critical cells in the discrete gradient vector field using a strategy informed by persistent homology. Simple working Python code for our algorithms for efficient vector field traversal is included. Example data are taken from micro-CT images of porous materials, an application area where accurate topological models of pore connectivity are vital for fluid-flow modelling.

  5. OPERATOR NORM INEQUALITIES BETWEEN TENSOR UNFOLDINGS ON THE PARTITION LATTICE.

    Science.gov (United States)

    Wang, Miaoyan; Duc, Khanh Dao; Fischer, Jonathan; Song, Yun S

    2017-05-01

    Interest in higher-order tensors has recently surged in data-intensive fields, with a wide range of applications including image processing, blind source separation, community detection, and feature extraction. A common paradigm in tensor-related algorithms advocates unfolding (or flattening) the tensor into a matrix and applying classical methods developed for matrices. Despite the popularity of such techniques, how the functional properties of a tensor changes upon unfolding is currently not well understood. In contrast to the body of existing work which has focused almost exclusively on matricizations, we here consider all possible unfoldings of an order- k tensor, which are in one-to-one correspondence with the set of partitions of {1, …, k }. We derive general inequalities between the l p -norms of arbitrary unfoldings defined on the partition lattice. In particular, we demonstrate how the spectral norm ( p = 2) of a tensor is bounded by that of its unfoldings, and obtain an improved upper bound on the ratio of the Frobenius norm to the spectral norm of an arbitrary tensor. For specially-structured tensors satisfying a generalized definition of orthogonal decomposability, we prove that the spectral norm remains invariant under specific subsets of unfolding operations.

  6. A detailed aerosol mixing state model for investigating interactions between mixing state, semivolatile partitioning, and coagulation

    OpenAIRE

    J. Lu; F. M. Bowman

    2010-01-01

    A new method for describing externally mixed particles, the Detailed Aerosol Mixing State (DAMS) representation, is presented in this study. This novel method classifies aerosols by both composition and size, using a user-specified mixing criterion to define boundaries between compositional populations. Interactions between aerosol mixing state, semivolatile partitioning, and coagulation are investigated with a Lagrangian box model that incorporates the DAMS approach. Model results predict th...

  7. Partitioning of fissile and radio-toxic materials from spent nuclear fuel

    International Nuclear Information System (INIS)

    Bychkov, A.V.; Skiba, O.V.; Kormilitsyn, M.V.

    2007-01-01

    Full text of publication follows. The term ''partitioning'' means separation of one group of radwaste components from another. Such technological approaches are mainly applied to extraction of long-lived fission products (Tc, I) and minor actinides (Np, Am, Cm) from the waste arising from spent nuclear fuel reprocessing. Transmutation of the extracted minor actinides should be performed in a reactor or some accelerated systems. The combination of these technologies, partitioning and transmutation (P and T), will reduce the radiotoxicity of radwaste. In recent decades, partitioning has been directly linked to spent fuel reprocessing. Therefore, the basic investigations have been focused on the partitioning of liquid wastes arising from the PUREX process. These subjects have been the most developed ones, but the processes of fine aqueous separation generates an extra amount of liquid waste. This fact has an effect on the nuclear fuel cycle economy. Therefore, some other advanced compact methods have also been studied. These are dry methods involving molten chlorides and fluorides, the methods based on a supercritical movable phase, etc. The report provides a brief review of information on the basic partitioning process flow-sheets developed in France, Japan, Russia and other countries. Recent approaches to partitioning have been mostly directed towards radio-toxic hazard reduction and ecology. In the future, partitioning should be closely bound up with reprocessing and other spent nuclear fuel management processes. Reprocessing/partitioning should also be aimed at solving the problems of safety (non-proliferation) and economy in a closed fuel cycle. It is necessary to change a future ''technological philosophy'' of reprocessing and partitioning. The basic spent fuel components (U, Pu, Th) are to be extracted only for recycling in a closed nuclear fuel cycle. If these elements are regarded as a waste, additional expenses are required for transmutation. If we consider

  8. Mesh Partitioning Algorithm Based on Parallel Finite Element Analysis and Its Actualization

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2013-01-01

    Full Text Available In parallel computing based on finite element analysis, domain decomposition is a key technique for its preprocessing. Generally, a domain decomposition of a mesh can be realized through partitioning of a graph which is converted from a finite element mesh. This paper discusses the method for graph partitioning and the way to actualize mesh partitioning. Relevant softwares are introduced, and the data structure and key functions of Metis and ParMetis are introduced. The writing, compiling, and testing of the mesh partitioning interface program based on these key functions are performed. The results indicate some objective law and characteristics to guide the users who use the graph partitioning algorithm and software to write PFEM program, and ideal partitioning effects can be achieved by actualizing mesh partitioning through the program. The interface program can also be used directly by the engineering researchers as a module of the PFEM software. So that it can reduce the application of the threshold of graph partitioning algorithm, improve the calculation efficiency, and promote the application of graph theory and parallel computing.

  9. Clinical evaluation of the partition model for estimating radiation doses from yttrium-90 microspheres in the treatment of hepatic cancer

    International Nuclear Information System (INIS)

    Ho, S.; Lau, W.Y.; Leung, T.W.T.; Chan, M.; Johnson, P.J.; Li, A.K.C.

    1997-01-01

    Radiation doses to the tumour and non-tumorous liver compartments from yttrium-90 microspheres in the treatment of hepatic cancer, as estimated by a partition model, have been verified by correlation with the actual doses measured with a beta probe at open surgery. The validity of the doses to the lungs, the tumour and non-tumours liver compartment as estimated by the partition model was further evaluated in clinical settings. On the basis of the observation that one of three patients who received more than 30 Gy from a single treatment and one of two patients who received more than 50 Gy from multiple treatments developed radiation pneumonitis, it was deduced that an estimated lung dose 30 Gy as estimated by the partition model and were predicted to develop radiation pneumonitis, did so despite the use of partial hepatic embolization to reduce the degree of lung shunting. Furthermore, a higher radiological response rate and prolonged survival were found in the group of patients who received higher tumour doses, as estimated by the partition model, than in the group with lower estimated tumour doses. Thus the radiation doses estimated by the partition model can be used to predict (a) complication rate, (b) response rate and (c) duration of survival in the same manner as the actual radiation doses measured with a beta probe at open surgery. The partition model has made selective internal radiation therapy using 90 Y microspheres safe and repeatable without laparotomy. (orig.)

  10. Polyhedral Computations for the Simple Graph Partitioning Problem

    DEFF Research Database (Denmark)

    Sørensen, Michael Malmros

    The simple graph partitioning problem is to partition an edge-weighted graph into mutually disjoint subgraphs, each containing no more than b nodes, such that the sum of the weights of all edges in the subgraphs is maximal. In this paper we present a branch-and-cut algorithm for the problem that ...

  11. On the partition dimension of two-component graphs

    Indian Academy of Sciences (India)

    D O Haryeni

    2017-11-17

    Nov 17, 2017 ... Partition dimension; disconnected graph; component. 2010 Mathematics Subject Classification. 05C12, 05C15. 1. Introduction. The study of the partition dimension for graphs was initiated by Chartrand et al. [2] aimed at finding a new way to solve the problem in metric dimensions of graphs. Many results.

  12. Probabilistic Decision Based Block Partitioning for Future Video Coding

    KAUST Repository

    Wang, Zhao; Wang, Shiqi; Zhang, Jian; Wang, Shanshe; Ma, Siwei

    2017-01-01

    , the mode decision problem is casted into a probabilistic framework to select the final partition based on the confidence interval decision strategy. Experimental results show that the proposed CIET algorithm can speed up QTBT block partitioning structure

  13. Optimum sample length for estimating anchovy size distribution and the proportion of juveniles per fishing set for the Peruvian purse-seine fleet

    Directory of Open Access Journals (Sweden)

    Rocío Joo

    2017-04-01

    Full Text Available The length distribution of catches represents a fundamental source of information for estimating growth and spatio-temporal dynamics of cohorts. The length distribution of caught is estimated based on samples of catched individuals. This work studies the optimum sample size of individuals at each fishing set in order to obtain a representative sample of the length and the proportion of juveniles in the fishing set. For that matter, we use anchovy (Engraulis ringens length data from different fishing sets recorded by observers at-sea from the On-board Observers Program from the Peruvian Marine Research Institute. Finally, we propose an optimum sample size for obtaining robust size and juvenile estimations. Though the application of this work corresponds to the anchovy fishery, the procedure can be applied to any fishery, either for on board or inland biometric measurements.

  14. Prediction of air-to-blood partition coefficients of volatile organic compounds using genetic algorithm and artificial neural network

    International Nuclear Information System (INIS)

    Konoz, Elahe; Golmohammadi, Hassan

    2008-01-01

    An artificial neural network (ANN) was constructed and trained for the prediction of air-to-blood partition coefficients of volatile organic compounds. The inputs of this neural network are theoretically derived descriptors that were chosen by genetic algorithm (GA) and multiple linear regression (MLR) features selection techniques. These descriptors are: R maximal autocorrelation of lag 1 weighted by atomic Sanderson electronegativities (R1E+), electron density on the most negative atom in molecule (EDNA), maximum partial charge for C atom (MXPCC), surface weighted charge partial surface area (WNSA1), fractional charge partial surface area (FNSA2) and atomic charge weighted partial positive surface area (PPSA3). The standard errors of training, test and validation sets for the ANN model are 0.095, 0.148 and 0.120, respectively. Result obtained showed that nonlinear model can simulate the relationship between structural descriptors and the partition coefficients of the molecules in data set accurately

  15. Partitioning of unstructured meshes for load balancing

    International Nuclear Information System (INIS)

    Martin, O.C.; Otto, S.W.

    1994-01-01

    Many large-scale engineering and scientific calculations involve repeated updating of variables on an unstructured mesh. To do these types of computations on distributed memory parallel computers, it is necessary to partition the mesh among the processors so that the load balance is maximized and inter-processor communication time is minimized. This can be approximated by the problem, of partitioning a graph so as to obtain a minimum cut, a well-studied combinatorial optimization problem. Graph partitioning algorithms are discussed that give good but not necessarily optimum solutions. These algorithms include local search methods recursive spectral bisection, and more general purpose methods such as simulated annealing. It is shown that a general procedure enables to combine simulated annealing with Kernighan-Lin. The resulting algorithm is both very fast and extremely effective. (authors) 23 refs., 3 figs., 1 tab

  16. Managing Network Partitions in Structured P2P Networks

    Science.gov (United States)

    Shafaat, Tallat M.; Ghodsi, Ali; Haridi, Seif

    Structured overlay networks form a major class of peer-to-peer systems, which are touted for their abilities to scale, tolerate failures, and self-manage. Any long-lived Internet-scale distributed system is destined to face network partitions. Consequently, the problem of network partitions and mergers is highly related to fault-tolerance and self-management in large-scale systems. This makes it a crucial requirement for building any structured peer-to-peer systems to be resilient to network partitions. Although the problem of network partitions and mergers is highly related to fault-tolerance and self-management in large-scale systems, it has hardly been studied in the context of structured peer-to-peer systems. Structured overlays have mainly been studied under churn (frequent joins/failures), which as a side effect solves the problem of network partitions, as it is similar to massive node failures. Yet, the crucial aspect of network mergers has been ignored. In fact, it has been claimed that ring-based structured overlay networks, which constitute the majority of the structured overlays, are intrinsically ill-suited for merging rings. In this chapter, we motivate the problem of network partitions and mergers in structured overlays. We discuss how a structured overlay can automatically detect a network partition and merger. We present an algorithm for merging multiple similar ring-based overlays when the underlying network merges. We examine the solution in dynamic conditions, showing how our solution is resilient to churn during the merger, something widely believed to be difficult or impossible. We evaluate the algorithm for various scenarios and show that even when falsely detecting a merger, the algorithm quickly terminates and does not clutter the network with many messages. The algorithm is flexible as the tradeoff between message complexity and time complexity can be adjusted by a parameter.

  17. Parallel clustering algorithm for large-scale biological data sets.

    Science.gov (United States)

    Wang, Minchao; Zhang, Wu; Ding, Wang; Dai, Dongbo; Zhang, Huiran; Xie, Hao; Chen, Luonan; Guo, Yike; Xie, Jiang

    2014-01-01

    Recent explosion of biological data brings a great challenge for the traditional clustering algorithms. With increasing scale of data sets, much larger memory and longer runtime are required for the cluster identification problems. The affinity propagation algorithm outperforms many other classical clustering algorithms and is widely applied into the biological researches. However, the time and space complexity become a great bottleneck when handling the large-scale data sets. Moreover, the similarity matrix, whose constructing procedure takes long runtime, is required before running the affinity propagation algorithm, since the algorithm clusters data sets based on the similarities between data pairs. Two types of parallel architectures are proposed in this paper to accelerate the similarity matrix constructing procedure and the affinity propagation algorithm. The memory-shared architecture is used to construct the similarity matrix, and the distributed system is taken for the affinity propagation algorithm, because of its large memory size and great computing capacity. An appropriate way of data partition and reduction is designed in our method, in order to minimize the global communication cost among processes. A speedup of 100 is gained with 128 cores. The runtime is reduced from serval hours to a few seconds, which indicates that parallel algorithm is capable of handling large-scale data sets effectively. The parallel affinity propagation also achieves a good performance when clustering large-scale gene data (microarray) and detecting families in large protein superfamilies.

  18. Partitioning net ecosystem carbon exchange into net assimilation and respiration using 13CO2 measurements: A cost-effective sampling strategy

    Science.gov (United States)

    OgéE, J.; Peylin, P.; Ciais, P.; Bariac, T.; Brunet, Y.; Berbigier, P.; Roche, C.; Richard, P.; Bardoux, G.; Bonnefond, J.-M.

    2003-06-01

    The current emphasis on global climate studies has led the scientific community to set up a number of sites for measuring the long-term biosphere-atmosphere net CO2 exchange (net ecosystem exchange, NEE). Partitioning this flux into its elementary components, net assimilation (FA), and respiration (FR), remains necessary in order to get a better understanding of biosphere functioning and design better surface exchange models. Noting that FR and FA have different isotopic signatures, we evaluate the potential of isotopic 13CO2 measurements in the air (combined with CO2 flux and concentration measurements) to partition NEE into FR and FA on a routine basis. The study is conducted at a temperate coniferous forest where intensive isotopic measurements in air, soil, and biomass were performed in summer 1997. The multilayer soil-vegetation-atmosphere transfer model MuSICA is adapted to compute 13CO2 flux and concentration profiles. Using MuSICA as a "perfect" simulator and taking advantage of the very dense spatiotemporal resolution of the isotopic data set (341 flasks over a 24-hour period) enable us to test each hypothesis and estimate the performance of the method. The partitioning works better in midafternoon when isotopic disequilibrium is strong. With only 15 flasks, i.e., two 13CO2 nighttime profiles (to estimate the isotopic signature of FR) and five daytime measurements (to perform the partitioning) we get mean daily estimates of FR and FA that agree with the model within 15-20%. However, knowledge of the mesophyll conductance seems crucial and may be a limitation to the method.

  19. Constructing ordinal partition transition networks from multivariate time series.

    Science.gov (United States)

    Zhang, Jiayang; Zhou, Jie; Tang, Ming; Guo, Heng; Small, Michael; Zou, Yong

    2017-08-10

    A growing number of algorithms have been proposed to map a scalar time series into ordinal partition transition networks. However, most observable phenomena in the empirical sciences are of a multivariate nature. We construct ordinal partition transition networks for multivariate time series. This approach yields weighted directed networks representing the pattern transition properties of time series in velocity space, which hence provides dynamic insights of the underling system. Furthermore, we propose a measure of entropy to characterize ordinal partition transition dynamics, which is sensitive to capturing the possible local geometric changes of phase space trajectories. We demonstrate the applicability of pattern transition networks to capture phase coherence to non-coherence transitions, and to characterize paths to phase synchronizations. Therefore, we conclude that the ordinal partition transition network approach provides complementary insight to the traditional symbolic analysis of nonlinear multivariate time series.

  20. Microstructure and partitioning behavior characteristics in low carbon steels treated by hot-rolling direct quenching and dynamical partitioning processes

    International Nuclear Information System (INIS)

    Li, Yun-jie; Li, Xiao-lei; Yuan, Guo; Kang, Jian; Chen, Dong; Wang, Guo-dong

    2016-01-01

    In this work, a new process and composition design are proposed for “quenching and partitioning” or Q&P treatment. Three low carbon steels were treated by hot-rolling direct quenching and dynamical partitioning processes (DQ&P). The effects of proeutectoid ferrite and carbon concentration on microstructure evolution and mechanical properties were investigated. The present work obtained DQ&P prototype steels with good mechanical properties and established a new notion on compositions for Q&P processing. Microstructures were characterized by means of electro probe microanalyzer (EPMA), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) and X-ray diffraction (XRD), especially the morphology and size of retained austenite. Mechanical properties were measured by uniaxial tensile tests. The results indicated that introducing proeutectoid ferrite can increase the volume fraction of retained austenite and thus improve mechanical properties. TEM observation showed that retained austenite included the film-like inter-lath austenite and blocky austenite located in martensite/ferrite interfaces or surrounded by ferrites. It was interesting that when the carbon concentration is as low as ~ 0.078%, the film-like inter-lath untransformed austenite cannot be stabilized to room temperature and almost all of them transformed into twin martensite. The blocky retained austenite strengthened the interfaces and transformed into twin martensite during the tensile deformation process. The PSEs of specimens all exceeded 20 GPa.%. - Highlights: •This study focused on a new process: Q&P process applying dynamical partitioning. •Ferrite can increase the volume fraction of retained austenite. •The film-like austenite and the blocky austenite were observed. •The low carbon steels treated by new process reached PSEs higher than 20 GPa.%.

  1. Spatio-temporal evaluation of emerging contaminants and their partitioning along a Brazilian watershed.

    Science.gov (United States)

    de Sousa, Diana Nara Ribeiro; Mozeto, Antonio Aparecido; Carneiro, Renato Lajarim; Fadini, Pedro Sergio

    2018-02-01

    The occurrence, partitioning, and spatio-temporal distribution of seven pharmaceuticals for human use, three steroid hormones and one personal care product were determined in surface water, suspended particulate matter (SPM), and sediment of Piraí Creek and Jundiaí River (Jundiaí River Basin, São Paulo, Brazil). The maximum average detected concentrations of the compounds in the Piraí River samples were contaminants most frequently detected in sediment and SPM samples. Triclosan had the highest average proportion of SPM as opposed to in the aqueous phase (> 75%). Contaminants with acid functional groups showed, in general, a lower tendency to bind to particulate matter and sediments. In addition, hydrophobicity had an important effect on their environmental partitioning. The spatial distribution of contaminants along the Jundiaí River was mainly affected by the higher concentration of contaminants in water samples collected downstream from a sewage treatment plant (STP). The results obtained here clearly showed the importance of the analysis of some contaminants in the whole water, meaning both dissolved and particulate compartments in the water, and that the partitioning is ruled by a set of parameters associated to the physicochemical characteristics of contaminants and the matrix properties of the studied, which need be considered in an integrated approach to understand the fate of emerging chemical contaminants in aquatic environments.

  2. Phylogenetic relationships in Asarum: Effect of data partitioning and a revised classification.

    Science.gov (United States)

    Sinn, Brandon T; Kelly, Lawrence M; Freudenstein, John V

    2015-05-01

    Generic boundaries and infrageneric relationships among the charismatic temperate magnoliid Asarum sensu lato (Aristolochiaceae) have long been uncertain. Previous molecular phylogenetic analyses used either plastid or nuclear loci alone and varied greatly in their taxonomic implications for the genus. We analyzed additional molecular markers from the nuclear and plastid genomes, reevaluated the possibility of a derived loss of autonomous self-pollination, and investigated the topological effects of matrix-partitioning-scheme choice. We sequenced seven plastid regions and the nuclear ITS1-ITS2 region of 58 individuals representing all previously recognized Asarum s.l. segregate genera and the monotypic genus Saruma. Matrices were partitioned using common a priori partitioning schemes and PartitionFinder. Topologies that were recovered using a priori partitioning of matrices differed from those recovered using a PartitionFinder-selected scheme, and by analysis method. We recovered six monophyletic groups that we circumscribed into three subgenera and six sections. Putative fungal mimic characters served as synapomorphies only for subgenus Heterotropa. Subgenus Geotaenium, a new subgenus, was recovered as sister to the remainder of Asarum by ML analyses of highly partitioned datasets. Section Longistylis, also newly named, is sister to section Hexastylis. Our analyses do not unambiguously support a single origin for all fungal-mimicry characters. Topologies recovered through the analysis of PartitionFinder-optimized matrices can differ drastically from those inferred from a priori partitioned matrices, and by analytical method. We recommend that investigators evaluate the topological effects of matrix partitioning using multiple methods of phylogenetic reconstruction. © 2015 Botanical Society of America, Inc.

  3. Metal/silicate partitioning of Pt and the origin of the "late veneer"

    Science.gov (United States)

    Ertel, W.; Walter, M. J.; Drake, M. J.; Sylvester, P. J.

    2002-12-01

    Highly siderophile elements (HSEs) are perfect tools for investigating core forming processes in planetary bodies due to their Fe-loving (siderophile) geochemical behavior. Tremendous scientific effort was invested into this field during the past 10 years - mostly in 1 atm experiments. However, little is known about their high-pressure geochemistry and partitioning behavior between core and mantle forming phases. This knowledge is essential to distinguish between equilibrium (Magma Ocean) and non-equilibrium (heterogeneous accretion, late veneer) models for the accretion history for the early Earth. We therefore chose to investigate the partitioning behavior of Pt up to pressures of 140 kbar (14 GPa) and temperatures of 1950°C. The used melt composition - identical to melt systems used in 1 atm experiments - is the eutectic composition of Anorthite-Diopside (AnDi), a pseudo-basalt. A series of runs were performed which were internaly buffered by the piston cylinder apparatus, and were followed by duplicate experiments buffered in the AnDi-C-CO2 system. These experiments constitute reversals since they approach equilibrium from an initially higher and lower Pt solubility (8 ppm in the non-buffered runs, and essentially Pt free in the buffered runs). Experimental charges were encapsulated in Pt capsules which served as source for Pt. Experiments up to 20 kbar were performed in a Quickpress piston cylinder apparatus, while experiments at higher pressures were performed in a Walker-type (Tucson, AZ) and a Kawai-type (Misasa, Japan) multi anvil apparatus. Time series experiments were performed in piston-cylinder runs to determine minimum run durations for the achievement of equilibrium, and to guarantee high-quality partitioning data. 6 hours was found to be sufficient to obtain equilibrium. In practice, all experiments exceeded 12 hours to assure equilibrium. In a second set of runs the temperature dependence of the partitioning behavior of Pt was investigated between

  4. Partitioning of polar and non-polar neutral organic chemicals into human and cow milk.

    Science.gov (United States)

    Geisler, Anett; Endo, Satoshi; Goss, Kai-Uwe

    2011-10-01

    The aim of this work was to develop a predictive model for milk/water partition coefficients of neutral organic compounds. Batch experiments were performed for 119 diverse organic chemicals in human milk and raw and processed cow milk at 37°C. No differences (milk were observed. The polyparameter linear free energy relationship model fit the calibration data well (SD=0.22 log units). An experimental validation data set including hormones and hormone active compounds was predicted satisfactorily by the model. An alternative modelling approach based on log K(ow) revealed a poorer performance. The model presented here provides a significant improvement in predicting enrichment of potentially hazardous chemicals in milk. In combination with physiologically based pharmacokinetic modelling this improvement in the estimation of milk/water partitioning coefficients may allow a better risk assessment for a wide range of neutral organic chemicals. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Metal partitioning and uptake in central Ontario forests

    International Nuclear Information System (INIS)

    Watmough, Shaun A.; Dillon, Peter J.; Epova, Ekaterina N.

    2005-01-01

    Evaluation of the potential environmental risk posed by metals depends to a great extent on modeling the fate and mobility of metals with soil-solution partitioning coefficients (K d ). However, the effect of biological cycling on metal partitioning is rarely considered in standard risk assessments. We determined soil-solution partitioning coefficients for 5 metals (Cd, Zn, Pb, Co and Ni) at 46 forested sites that border the Precambrian Shield in central Ontario, where soil pH aq varied from 3.9 to 8.1. Foliage from the dominant tree species and forest floor samples were also collected from each site to compare their metal levels with K d predictions. Analogous to other studies, log K d values for all metals were predicted by empirical linear regression with soil pH (r 2 = 0.66-0.72), demonstrating that metal partitioning between soil and soil solution can be reliably predicted for relatively unpolluted forest mineral soils by soil pH. In contrast, whereas the so-called bioavailable water-soluble metal fraction could be predicted from soil pH, metal concentrations in foliage and the forest floor at each site were not consistently related to pH. Risk assessment of metals should take into account the role of biota in metal cycling and partitioning in forests, particularly if metal bio-accumulation and chronic toxicity in the food chain, rather than metal mobility in soils, are of primary concern. - Metal cycling by plants should be considered in risk assessment studies

  6. PACE: A dynamic programming algorithm for hardware/software partitioning

    DEFF Research Database (Denmark)

    Knudsen, Peter Voigt; Madsen, Jan

    1996-01-01

    This paper presents the PACE partitioning algorithm which is used in the LYCOS co-synthesis system for partitioning control/dataflow graphs into hardware and software parts. The algorithm is a dynamic programming algorithm which solves both the problem of minimizing system execution time...

  7. Selection of the Maximum Spatial Cluster Size of the Spatial Scan Statistic by Using the Maximum Clustering Set-Proportion Statistic.

    Science.gov (United States)

    Ma, Yue; Yin, Fei; Zhang, Tao; Zhou, Xiaohua Andrew; Li, Xiaosong

    2016-01-01

    Spatial scan statistics are widely used in various fields. The performance of these statistics is influenced by parameters, such as maximum spatial cluster size, and can be improved by parameter selection using performance measures. Current performance measures are based on the presence of clusters and are thus inapplicable to data sets without known clusters. In this work, we propose a novel overall performance measure called maximum clustering set-proportion (MCS-P), which is based on the likelihood of the union of detected clusters and the applied dataset. MCS-P was compared with existing performance measures in a simulation study to select the maximum spatial cluster size. Results of other performance measures, such as sensitivity and misclassification, suggest that the spatial scan statistic achieves accurate results in most scenarios with the maximum spatial cluster sizes selected using MCS-P. Given that previously known clusters are not required in the proposed strategy, selection of the optimal maximum cluster size with MCS-P can improve the performance of the scan statistic in applications without identified clusters.

  8. Disk partition function and oscillatory rolling tachyons

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  9. Temperature dependence of the particle/gas partition coefficient: An application to predict indoor gas-phase concentrations of semi-volatile organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Wenjuan, E-mail: Wenjuan.Wei@cstb.fr [University of Paris-Est, Scientific and Technical Center for Building (CSTB), Health and Comfort Department, French Indoor Air Quality Observatory (OQAI), 84 Avenue Jean Jaurès, Champs sur Marne, 77447 Marne la Vallée Cedex 2 (France); Mandin, Corinne [University of Paris-Est, Scientific and Technical Center for Building (CSTB), Health and Comfort Department, French Indoor Air Quality Observatory (OQAI), 84 Avenue Jean Jaurès, Champs sur Marne, 77447 Marne la Vallée Cedex 2 (France); INSERM-U1085, Irset-Research Institute for Environmental and Occupational Health, Rennes (France); LERES-Environment and Health Research Laboratory (Irset and EHESP Technologic Platform), Rennes (France); Blanchard, Olivier [EHESP-School of Public Health, Sorbonne Paris Cité, Rennes (France); INSERM-U1085, Irset-Research Institute for Environmental and Occupational Health, Rennes (France); Mercier, Fabien [EHESP-School of Public Health, Sorbonne Paris Cité, Rennes (France); LERES-Environment and Health Research Laboratory (Irset and EHESP Technologic Platform), Rennes (France); INSERM-U1085, Irset-Research Institute for Environmental and Occupational Health, Rennes (France); Pelletier, Maud [EHESP-School of Public Health, Sorbonne Paris Cité, Rennes (France); INSERM-U1085, Irset-Research Institute for Environmental and Occupational Health, Rennes (France); Le Bot, Barbara [EHESP-School of Public Health, Sorbonne Paris Cité, Rennes (France); LERES-Environment and Health Research Laboratory (Irset and EHESP Technologic Platform), Rennes (France); INSERM-U1085, Irset-Research Institute for Environmental and Occupational Health, Rennes (France); and others

    2016-09-01

    The indoor gas-phase concentrations of semi-volatile organic compounds (SVOCs) can be predicted from their respective concentrations in airborne particles by applying the particle/gas partitioning equilibrium. The temperature used for partitioning is often set to 25 °C. However, indoor temperatures frequently differ from this reference value. This assumption may result in errors in the predicted equilibrium gas-phase SVOC concentrations. To improve the prediction model, the temperature dependence of the particle/gas partition coefficient must be addressed. In this paper, a theoretical relationship between the particle/gas partition coefficient and temperature was developed based on the SVOC absorptive mechanism. The SVOC particle/gas partition coefficients predicted by employing the derived theoretical relationship agree well with the experimental data retrieved from the literature (R > 0.93). The influence of temperature on the equilibrium gas-phase SVOC concentration was quantified by a dimensionless analysis of the derived relationship between the SVOC particle/gas partition coefficient and temperature. The predicted equilibrium gas-phase SVOC concentration decreased by between 31% and 53% when the temperature was lowered by 6 °C, while it increased by up to 750% when the indoor temperature increased from 15 °C to 30 °C. - Highlights: • A theoretical relationship between K{sub p} and temperature was developed. • The relationship was based on the SVOC absorptive mechanism. • The temperature impact was quantified by a dimensionless analysis.

  10. European Europart integrated project on actinide partitioning

    International Nuclear Information System (INIS)

    Madic, C.; Hudson, M.J.

    2005-01-01

    This poster presents the objectives of EUROPART, a scientific integrated project between 24 European partners, mostly funded by the European Community within the FP6. EUROPART aims at developing chemical partitioning processes for the so-called minor actinides (MA) contained in nuclear wastes, i.e. from Am to Cf. In the case of dedicated spent fuels or targets, the actinides to be separated also include U, Pu and Np. The techniques considered for the separation of these radionuclides belong to the fields of hydrometallurgy and pyrometallurgy, as in the previous FP5 programs named PARTNEW and PYROREP. The two main axes of research within EUROPART will be: The partitioning of MA (from Am to Cf) from high burn-up UO x fuels and multi-recycled MOx fuels; the partitioning of the whole actinide family for recycling, as an option for advanced dedicated fuel cycles (and in connection with the studies to be performed in the EUROTRANS integrated project). In hydrometallurgy, the research is organised into five Work Packages (WP). Four WP are dedicated to the study of partitioning methods mainly based on the use of solvent extraction methods, one WP is dedicated to the development of actinide co-conversion methods for fuel or target preparation. The research in pyrometallurgy is organized into four WP, listed hereafter: development of actinide partitioning methods, study of the basic chemistry of trans-curium elements in molten salts, study of the conditioning of the wastes, some system studies. Moreover, a strong management team will be concerned not only with the technical and financial issues arising from EUROPART, but also with information, communication and benefits for Europe. Training and education of young researchers will also pertain to the project. EUROPART has also established collaboration with US DOE and Japanese CRIEPI. (authors)

  11. The partitioning of uranium and neptunium onto hydrothermally altered concrete

    International Nuclear Information System (INIS)

    Zhao, P.; Allen, P.G.; Sylwester, E.R.; Viani, B.E.

    2000-01-01

    Partition coefficients (K d ) of U(VI) and Np(V) on untreated and hydrothermally altered concrete were measured in 0.01 M NaCl and 0.01 M NaHCO 3 solutions as functions of concentration of the radionuclides, pH, and time. The partition coefficients for both U(VI) and Np(V) on hydrothermally altered concrete are significantly lower than those on untreated concrete. The partition of both U(VI) and Np(V) are pH dependent, although the pH dependence does not appear to reflect precipitation of U and Np-bearing phases. Both sorption and precipitation are likely processes controlling partitioning of U to concrete; sorption is the most likely process controlling the partitioning of Np to concrete. The presence of 0.01 M carbonate species in solution decreases K d of U(VI) for both hydrothermally altered and untreated concrete from ≥ 10 4 mL/g to ∝ 400 to 1000 mL/g indicating a significant impact on U(VI) sorption. In contrast, the presence of carbonate only reduced the K d of Np(V) by one order of magnitude or less. X-ray absorption spectroscopy analysis of U/concrete mixtures at different pHs and times indicate that uranyl ions are partitioned as monomeric species on untreated concrete, but oligomeric species on hydrothermally altered concrete. Similar analysis of Np/concrete mixtures shows that about half of the partitioned Np(V) is reduced to Np(IV) over a period of 6 months. (orig.)

  12. Trace Element Partitioning Between low-Ca Pyroxene and Ultracalcic Liquids.

    Science.gov (United States)

    Pertermann, M.; Schmidt, M. W.; Pettke, T.

    2003-12-01

    Low-Ca pyroxene or pigeonite ( ˜0.25-0.35 Ca per formula unit, pfu) is an important residual phase during high temperature melting of refractory mantle (e.g., ankaramite formation). High-Ca cpx (>0.6-0.7 Ca pfu) may be residual to relatively low temperature melting of fertile mantle (MOR and OI), but the opx-cpx solvus narrows considerably at higher temperatures (>1330-1350° C), leading to coexisting opx and low-Ca cpx. Little is known about the trace element partitioning of such low-Ca cpx at upper mantle conditions. Our new partitioning experiments investigate the role of low-Ca cpx during melting of depleted peridotite. Nominally anhydrous experiments with graphite-lined Pt-capsules were conducted at 1.4 GPa and 1360-1370° C. The synthetic starting material is close in composition to an ultracalcic liquid saturated in opx+pigeonite+olivine+spinel. The experiments yielded assemblages of glass, low-Ca cpx, ol, and minor Cr-spinel; opx is absent. The low-Ca clinopyroxenes have 0.20 and 0.32 Ca pfu at 1370 and 1360° C, respectively, and tetrahedral Al of 0.046 and 0.067 pfu. The liquids have ˜50 wt% SiO2, ˜12.5 wt% CaO and CaO/Al2O3 of 1.44-1.54. Pyroxenes and glasses were analyzed for trace elements (La, Ce, Nd, Sm, Eu, Gd, Dy, Er Yb, Lu, Sc, Y, Sr, Zr, Hf, V, Cr, Mn, Co, Zn) by LA-ICP-MS using a 193 nm ArF excimer laser coupled to an Elan 6100 mass spectrometer. Ablation occurred in He, and ablation spot sizes were 15-30 μ m for minerals and 50 μ m for glasses. Trace element concentrations in pyroxenes were low for most 3+ and 4+ cations. This resulted in small mineral/melt partition coefficients (D-values), approximately an order of magnitude lower than those for high-Ca cpx associated with peridotite melting, thus making the low-Ca cpx partitioning behavior rather similar to the behavior of peridotitic opx. Cpx with 0.32 Ca pfu has slightly elevated D-values for 3+ cations when compared to the 0.20 Ca pfu cpx: DSc = 0.45, DY = 0.11, DSm = 0.054 and DYb

  13. Monotonicity Conditions for Multirate and Partitioned Explicit Runge-Kutta Schemes

    KAUST Repository

    Hundsdorfer, Willem; Mozartova, Anna; Savcenco, Valeriu

    2013-01-01

    of partitioned Runge-Kutta methods. It will also be seen that the incompatibility of consistency and mass-conservation holds for ‘genuine’ multirate schemes, but not for general partitioned methods.

  14. PuLP/XtraPuLP : Partitioning Tools for Extreme-Scale Graphs

    Energy Technology Data Exchange (ETDEWEB)

    2017-09-21

    PuLP/XtraPulp is software for partitioning graphs from several real-world problems. Graphs occur in several places in real world from road networks, social networks and scientific simulations. For efficient parallel processing these graphs have to be partitioned (split) with respect to metrics such as computation and communication costs. Our software allows such partitioning for massive graphs.

  15. Periodic Schur process, cylindric partitions and N=2* theory

    International Nuclear Information System (INIS)

    Iqbal, Amer; Kozcaz, Can; Sohail, Tanweer

    2011-01-01

    Type IIA string theory compactified on an elliptic CY3-fold gives rise to N=2U(1) gauge theory with an adjoint hypermultiplet. We study the refined open and closed topological string partition functions of this geometry using the refined topological vertex. We show that these partition functions, open and closed, are examples of periodic Schur process and are related to the generating function of the cylindric partitions if the Kaehler parameters are quantized in units of string coupling. The level-rank duality appears as the exchange symmetry of the two Kaehler parameters of the elliptic CY3-fold.

  16. Radio Wave Propagation Scene Partitioning for High-Speed Rails

    Directory of Open Access Journals (Sweden)

    Bo Ai

    2012-01-01

    Full Text Available Radio wave propagation scene partitioning is necessary for wireless channel modeling. As far as we know, there are no standards of scene partitioning for high-speed rail (HSR scenarios, and therefore we propose the radio wave propagation scene partitioning scheme for HSR scenarios in this paper. Based on our measurements along the Wuhan-Guangzhou HSR, Zhengzhou-Xian passenger-dedicated line, Shijiazhuang-Taiyuan passenger-dedicated line, and Beijing-Tianjin intercity line in China, whose operation speeds are above 300 km/h, and based on the investigations on Beijing South Railway Station, Zhengzhou Railway Station, Wuhan Railway Station, Changsha Railway Station, Xian North Railway Station, Shijiazhuang North Railway Station, Taiyuan Railway Station, and Tianjin Railway Station, we obtain an overview of HSR propagation channels and record many valuable measurement data for HSR scenarios. On the basis of these measurements and investigations, we partitioned the HSR scene into twelve scenarios. Further work on theoretical analysis based on radio wave propagation mechanisms, such as reflection and diffraction, may lead us to develop the standard of radio wave propagation scene partitioning for HSR. Our work can also be used as a basis for the wireless channel modeling and the selection of some key techniques for HSR systems.

  17. Dynamic State Space Partitioning for External Memory Model Checking

    DEFF Research Database (Denmark)

    Evangelista, Sami; Kristensen, Lars Michael

    2009-01-01

    We describe a dynamic partitioning scheme usable by model checking techniques that divide the state space into partitions, such as most external memory and distributed model checking algorithms. The goal of the scheme is to reduce the number of transitions that link states belonging to different...

  18. Efficient Partitioning of Large Databases without Query Statistics

    Directory of Open Access Journals (Sweden)

    Shahidul Islam KHAN

    2016-11-01

    Full Text Available An efficient way of improving the performance of a database management system is distributed processing. Distribution of data involves fragmentation or partitioning, replication, and allocation process. Previous research works provided partitioning based on empirical data about the type and frequency of the queries. These solutions are not suitable at the initial stage of a distributed database as query statistics are not available then. In this paper, I have presented a fragmentation technique, Matrix based Fragmentation (MMF, which can be applied at the initial stage as well as at later stages of distributed databases. Instead of using empirical data, I have developed a matrix, Modified Create, Read, Update and Delete (MCRUD, to partition a large database properly. Allocation of fragments is done simultaneously in my proposed technique. So using MMF, no additional complexity is added for allocating the fragments to the sites of a distributed database as fragmentation is synchronized with allocation. The performance of a DDBMS can be improved significantly by avoiding frequent remote access and high data transfer among the sites. Results show that proposed technique can solve the initial partitioning problem of large distributed databases.

  19. Molecular-based recursive partitioning analysis model for glioblastoma in the temozolomide era a correlative analysis based on nrg oncology RTOG 0525

    NARCIS (Netherlands)

    Bell, Erica Hlavin; Pugh, Stephanie L.; McElroy, Joseph P.; Gilbert, Mark R.; Mehta, Minesh; Klimowicz, Alexander C.; Magliocco, Anthony; Bredel, Markus; Robe, Pierre; Grosu, Anca L.; Stupp, Roger; Curran, Walter; Becker, Aline P.; Salavaggione, Andrea L.; Barnholtz-Sloan, Jill S.; Aldape, Kenneth; Blumenthal, Deborah T.; Brown, Paul D.; Glass, Jon; Souhami, Luis; Lee, R. Jeffrey; Brachman, David; Flickinger, John; Won, Minhee; Chakravarti, Arnab

    2017-01-01

    IMPORTANCE: There is a need for a more refined, molecularly based classification model for glioblastoma (GBM) in the temozolomide era. OBJECTIVE: To refine the existing clinically based recursive partitioning analysis (RPA) model by incorporating molecular variables. DESIGN, SETTING, AND

  20. Decomposing a planar graph of girth 5 into an independent set and a forest

    DEFF Research Database (Denmark)

    Kawarabayashi, Ken-ichi; Thomassen, Carsten

    2009-01-01

    We use a list-color technique to extend the result of Borodin and Glebov that the vertex set of every planar graph of girth at least 5 can be partitioned into an independent set and a set which induces a forest. We apply this extension to also extend Grötzsch's theorem that every planar triangle-...

  1. Modeling response of species to microcontaminants: comparative ecotoxicology by (sub)lethal body burdens as a function of species size and partition ratio of chemicals.

    Science.gov (United States)

    Hendriks, A J

    1995-11-01

    A model was designed and calibrated with accumulation data to calculate the internal concentrations of microcontaminants in organisms as a function of a few constants and variables. The main factors are the exposure time, the external exposure concentration, the partition ratio of the compound, and the size of the taxon concerned. The model was applied to calculate the lethal and sublethal body burdens of several priority compounds and some major taxa. Estimations were generally confirmed at the order of magnitude level by measured residues and applied doses if available. According to the estimations, most priority compounds chosen were critical for most taxa above internal concentrations of 0.1 mmol.kg-1 wet wt. Trichloromethane, 1,2,4-trichlorobenzene, and hexachlorobenzene were lethal above this level only, whereas other organic microcontaminants affected at least some taxa at lower body burdens. The log(Kow) of the organic compounds ranged from 2.0 to 7.0. Keeping in mind that bioconcentration and -magnification ratios for metals may be quite variable, the lowest critical residues estimated were just below the value of 0.1 mmol.kg-1 wet wt. Here, external concentrations encountered in natural habitats seem to be a promising tool for predictive comparative ecotoxicology. The critical body burdens for plants and invertebrates may have been overestimated due to uncertainty about the parameters. Among the different taxa, however, the fish families chosen (Salmonidae and Cyprinidae) seem to be most sensitive to most compounds. Internal response concentrations of the herbicide atrazine were the lowest in micro- and macrophytes, whereas parathion affected invertebrates at low levels. The database that provided the external response concentrations was also consulted to estimate so-called extrapolation or safety factors. On average, long-term no effect concentrations in water are estimated to be about 10-30 times below short-term median lethal levels. In general, short

  2. Partitioning and transmutation. Annual Report 1997

    Energy Technology Data Exchange (ETDEWEB)

    Enarsson, Aa; Landgren, A; Liljenzin, J O; Skaalberg, M; Spjuth, L [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Nuclear Chemistry

    1997-12-01

    The current research project on partitioning and transmutation at the Dept. of Nuclear Chemistry, CTH, has the primary objective to investigate separation processes useful in connection with transmutation of long-lived radionuclides in high level nuclear waste. Partitioning is necessary in order to recover and purify the elements before and after each irradiation in a P and T treatment. In order to achieve a high transmutation efficiency the chemical separation process used must have small losses to various waste streams. At present, only aqueous based separation processes are known to be able to achieve the high recovery and separation efficiencies necessary for a useful P and T process. Refs, figs, tabs.

  3. Using measured octanol-air partition coefficients to explain environmental partitioning of organochlorine pesticides.

    Science.gov (United States)

    Shoeib, Mahiba; Harner, Tom

    2002-05-01

    Octanol-air partition coefficients (Koa) were measured directly for 19 organochlorine (OC) pesticides over the temperature range of 5 to 35 degrees C. Values of log Koa at 25 degrees C ranged over three orders of magnitude, from 7.4 for hexachlorobenzene to 10.1 for 1,1-dichloro-2,2-bis(p-chlorophenyl) ethane. Measured values were compared to values calculated as KowRT/H (where R is the ideal gas constant [8.314 J mol(-1) K(-1)], T is absolute temperature, and H is Henry's law constant) were, in general, larger. Discrepancies of up to three orders of magnitude were observed, highlighting the need for direct measurements of Koa. Plots of Koa versus inverse absolute temperature exhibited a log-linear correlation. Enthalpies of phase transition between octanol and air (deltaHoa) were determined from the temperature slopes and were in the range of 56 to 105 kJ mol(-1) K(-1). Activity coefficients in octanol (gamma(o)) were determined from Koa and reported supercooled liquid vapor pressures (pL(o)), and these were in the range of 0.3 to 12, indicating near-ideal solution behavior. Differences in Koa values for structural isomers of hexachlorocyclohexane were also explored. A Koa-based model was described for predicting the partitioning of OC pesticides to aerosols and used to calculate particulate fractions at 25 and -10 degrees C. The model also agreed well with experimental results for several OC pesticides that were equilibrated with urban aerosols in the laboratory. A log-log regression of the particle-gas partition coefficient versus Koa had a slope near unity, indicating that octanol is a good surrogate for the aerosol organic matter.

  4. Surface Modifications of Support Partitions for Stabilizing Biomimetic Membrane Arrays

    DEFF Research Database (Denmark)

    Perry, Mark; Hansen, Jesper Schmidt; Jensen, Karin Bagger Stibius

    2011-01-01

    with a high signal-to-noise (s/n) ratio. We demonstratesd this by reconstituting gA and α-hemolysin (α-HL) into BLM arrays. The improvement in membrane array lifetime and s/n ratio demonstrates that surface plasma polymerization of the supporting partition can be used to increase the stability of biomimetic......Black lipid membrane (BLM) formation across apertures in an ethylene tetra-fluoroethylene (ETFE) partition separating two aqueous compartments is an established technique for the creation of biomimetic membranes. Recently multi-aperture BLM arrays have attracted interest and in order to increase...... BLM array stability we studied the effect of covalently modifying the partition substrate using surface plasma polymerization with hydrophobic n-hexene, 1-decene and hexamethyldisiloxane (HMDSO) as modification groups. Average lifetimes across singlesided HMDSO modified partitions or using 1-decene...

  5. Multimedia environmental chemical partitioning from molecular information

    International Nuclear Information System (INIS)

    Martinez, Izacar; Grifoll, Jordi; Giralt, Francesc; Rallo, Robert

    2010-01-01

    The prospect of assessing the environmental distribution of chemicals directly from their molecular information was analyzed. Multimedia chemical partitioning of 455 chemicals, expressed in dimensionless compartmental mass ratios, was predicted by SimpleBox 3, a Level III Fugacity model, together with the propagation of reported uncertainty for key physicochemical and transport properties, and degradation rates. Chemicals, some registered in priority lists, were selected according to the availability of experimental property data to minimize the influence of predicted information in model development. Chemicals were emitted in air or water in a fixed geographical scenario representing the Netherlands and characterized by five compartments (air, water, sediments, soil and vegetation). Quantitative structure-fate relationship (QSFR) models to predict mass ratios in different compartments were developed with support vector regression algorithms. A set of molecular descriptors, including the molecular weight and 38 counts of molecular constituents were adopted to characterize the chemical space. Out of the 455 chemicals, 375 were used for training and testing the QSFR models, while 80 were excluded from model development and were used as an external validation set. Training and test chemicals were selected and the domain of applicability (DOA) of the QSFRs established by means of self-organizing maps according to structural similarity. Best results were obtained with QSFR models developed for chemicals belonging to either the class [C] and [C; O], or the class with at least one heteroatom different than oxygen in the structure. These two class-specific models, with respectively 146 and 229 chemicals, showed a predictive squared coefficient of q 2 ≥ 0.90 both for air and water, which respectively dropped to q 2 ∼ 0.70 and 0.40 for outlying chemicals. Prediction errors were of the same order of magnitude as the deviations associated to the uncertainty of the

  6. Exact partition functions for gauge theories on Rλ3

    Directory of Open Access Journals (Sweden)

    Jean-Christophe Wallet

    2016-11-01

    Full Text Available The noncommutative space Rλ3, a deformation of R3, supports a 3-parameter family of gauge theory models with gauge-invariant harmonic term, stable vacuum and which are perturbatively finite to all orders. Properties of this family are discussed. The partition function factorizes as an infinite product of reduced partition functions, each one corresponding to the reduced gauge theory on one of the fuzzy spheres entering the decomposition of Rλ3. For a particular sub-family of gauge theories, each reduced partition function is exactly expressible as a ratio of determinants. A relation with integrable 2-D Toda lattice hierarchy is indicated.

  7. b-tree facets for the simple graph partitioning polytope

    DEFF Research Database (Denmark)

    Sørensen, Michael Malmros

    2004-01-01

    The simple graph partitioning problem is to partition an edge-weighted graph into mutually disjoint subgraphs, each consisting of no more than b nodes, such that the sum of the weights of all edges in the subgraphs is maximal. In this paper we introduce a large class of facet defining inequalities...... for the simple graph partitioning polytopes P_n(b), b >= 3, associated with the complete graph on n nodes. These inequalities are induced by a graph configuration which is built upon trees of cardinality b. We provide a closed-form theorem that states all necessary and sufficient conditions for the facet...... defining property of the inequalities. Udgivelsesdato: JUN...

  8. Factorisations for partition functions of random Hermitian matrix models

    International Nuclear Information System (INIS)

    Jackson, D.M.; Visentin, T.I.

    1996-01-01

    The partition function Z N , for Hermitian-complex matrix models can be expressed as an explicit integral over R N , where N is a positive integer. Such an integral also occurs in connection with random surfaces and models of two dimensional quantum gravity. We show that Z N can be expressed as the product of two partition functions, evaluated at translated arguments, for another model, giving an explicit connection between the two models. We also give an alternative computation of the partition function for the φ 4 -model.The approach is an algebraic one and holds for the functions regarded as formal power series in the appropriate ring. (orig.)

  9. REE Partition Coefficients from Synthetic Diogenite-Like Enstatite and the Implications of Petrogenetic Modeling

    Science.gov (United States)

    Schwandt, C. S.; McKay, G. A.

    1996-01-01

    Determining the petrogenesis of eucrites (basaltic achondrites) and diogenites (orthopyroxenites) and the possible links between the meteorite types was initiated 30 years ago by Mason. Since then, most investigators have worked on this question. A few contrasting theories have emerged, with the important distinction being whether or not there is a direct genetic link between eucrites and diogenites. One theory suggests that diogenites are cumulates resulting from the fractional crystallization of a parent magma with the eucrites crystallizing, from the residual magma after separation from the diogenite cumulates. Another model proposes that diogenites are cumulates formed from partial melts derived from a source region depleted by the prior generation of eucrite melts. It has also been proposed that the diogenites may not be directly linked to the eucrites and that they are cumulates derived from melts that are more orthopyroxene normative than the eucrites. This last theory has recently received more analytical and experimental support. One of the difficulties with petrogenetic modeling is that it requires appropriate partition coefficients for modeling because they are dependent on temperature, pressure, and composition. For this reason, we set out to determine minor- and trace-element partition coefficients for diogenite-like orthopyroxene. We have accomplished this task and now have enstatite/melt partition coefficients for Al, Cr, Ti, La, Ce, Nd, Sm, Eu, Dy, Er, Yb, and La.

  10. Hierarchical sets: analyzing pangenome structure through scalable set visualizations

    Science.gov (United States)

    2017-01-01

    Abstract Motivation: The increase in available microbial genome sequences has resulted in an increase in the size of the pangenomes being analyzed. Current pangenome visualizations are not intended for the pangenome sizes possible today and new approaches are necessary in order to convert the increase in available information to increase in knowledge. As the pangenome data structure is essentially a collection of sets we explore the potential for scalable set visualization as a tool for pangenome analysis. Results: We present a new hierarchical clustering algorithm based on set arithmetics that optimizes the intersection sizes along the branches. The intersection and union sizes along the hierarchy are visualized using a composite dendrogram and icicle plot, which, in pangenome context, shows the evolution of pangenome and core size along the evolutionary hierarchy. Outlying elements, i.e. elements whose presence pattern do not correspond with the hierarchy, can be visualized using hierarchical edge bundles. When applied to pangenome data this plot shows putative horizontal gene transfers between the genomes and can highlight relationships between genomes that is not represented by the hierarchy. We illustrate the utility of hierarchical sets by applying it to a pangenome based on 113 Escherichia and Shigella genomes and find it provides a powerful addition to pangenome analysis. Availability and Implementation: The described clustering algorithm and visualizations are implemented in the hierarchicalSets R package available from CRAN (https://cran.r-project.org/web/packages/hierarchicalSets) Contact: thomasp85@gmail.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:28130242

  11. Utilizing Maximal Independent Sets as Dominating Sets in Scale-Free Networks

    Science.gov (United States)

    Derzsy, N.; Molnar, F., Jr.; Szymanski, B. K.; Korniss, G.

    Dominating sets provide key solution to various critical problems in networked systems, such as detecting, monitoring, or controlling the behavior of nodes. Motivated by graph theory literature [Erdos, Israel J. Math. 4, 233 (1966)], we studied maximal independent sets (MIS) as dominating sets in scale-free networks. We investigated the scaling behavior of the size of MIS in artificial scale-free networks with respect to multiple topological properties (size, average degree, power-law exponent, assortativity), evaluated its resilience to network damage resulting from random failure or targeted attack [Molnar et al., Sci. Rep. 5, 8321 (2015)], and compared its efficiency to previously proposed dominating set selection strategies. We showed that, despite its small set size, MIS provides very high resilience against network damage. Using extensive numerical analysis on both synthetic and real-world (social, biological, technological) network samples, we demonstrate that our method effectively satisfies four essential requirements of dominating sets for their practical applicability on large-scale real-world systems: 1.) small set size, 2.) minimal network information required for their construction scheme, 3.) fast and easy computational implementation, and 4.) resiliency to network damage. Supported by DARPA, DTRA, and NSF.

  12. Effect of Strain, Region, and Tissue Composition on Glucose Partitioning in Meniscus Fibrocartilage.

    Science.gov (United States)

    Kleinhans, Kelsey L; Jackson, Alicia R

    2017-03-01

    A nearly avascular tissue, the knee meniscus relies on diffusive transport for nutritional supply to cells. Nutrient transport depends on solute partitioning in the tissue, which governs the amount of nutrients that can enter a tissue. The purpose of the present study was to investigate the effects of mechanical strain, tissue region, and tissue composition on the partition coefficient of glucose in meniscus fibrocartilage. A simple partitioning experiment was employed to measure glucose partitioning in porcine meniscus tissues from two regions (horn and central), from both meniscal components (medial and lateral), and at three levels of compression (0%, 10%, and 20%). Partition coefficient values were correlated to strain level, water volume fraction, and glycosaminoglycan (GAG) content of tissue specimens. Partition coefficient values ranged from 0.47 to 0.91 (n = 48). Results show that glucose partition coefficient is significantly (p < 0.001) affected by compression, decreasing with increasing strain. Furthermore, we did not find a statistically significant effect of tissue when comparing medial versus lateral (p = 0.181) or when comparing central and horn regions (p = 0.837). There were significant positive correlations between tissue water volume fraction and glucose partitioning for all groups. However, the correlation between GAG content and partitioning was only significant in the lateral horn group. Determining how glucose partitioning is affected by tissue composition and loading is necessary for understanding nutrient availability and related tissue health and/or degeneration. Therefore, this study is important for better understanding the transport and nutrition-related mechanisms of meniscal degeneration.

  13. Partitioning of copy-number genotypes in pedigrees

    Directory of Open Access Journals (Sweden)

    Andelfinger Gregor U

    2010-05-01

    Full Text Available Abstract Background Copy number variations (CNVs and polymorphisms (CNPs have only recently gained the genetic community's attention. Conservative estimates have shown that CNVs and CNPs might affect more than 10% of the genome and that they may be at least as important as single nucleotide polymorphisms in assessing human variability. Widely used tools for CNP analysis have been implemented in Birdsuite and PLINK for the purpose of conducting genetic association studies based on the unpartitioned total number of CNP copies provided by the intensities from Affymetrix's Genome-Wide Human SNP Array. Here, we are interested in partitioning copy number variations and polymorphisms in extended pedigrees for the purpose of linkage analysis on familial data. Results We have developed CNGen, a new software for the partitioning of copy number polymorphism using the integrated genotypes from Birdsuite with the Affymetrix platform. The algorithm applied to familial trios or extended pedigrees can produce partitioned copy number genotypes with distinct parental alleles. We have validated the algorithm using simulations on a complex pedigree structure using frequencies calculated from a real dataset of 300 genotyped samples from 42 pedigrees segregating a congenital heart defect phenotype. Conclusions CNGen is the first published software for the partitioning of copy number genotypes in pedigrees, making possible the use CNPs and CNVs for linkage analysis. It was implemented with the Python interpreter version 2.5.2. It was successfully tested on current Linux, Windows and Mac OS workstations.

  14. SAMPL5: 3D-RISM partition coefficient calculations with partial molar volume corrections and solute conformational sampling

    Science.gov (United States)

    Luchko, Tyler; Blinov, Nikolay; Limon, Garrett C.; Joyce, Kevin P.; Kovalenko, Andriy

    2016-11-01

    Implicit solvent methods for classical molecular modeling are frequently used to provide fast, physics-based hydration free energies of macromolecules. Less commonly considered is the transferability of these methods to other solvents. The Statistical Assessment of Modeling of Proteins and Ligands 5 (SAMPL5) distribution coefficient dataset and the accompanying explicit solvent partition coefficient reference calculations provide a direct test of solvent model transferability. Here we use the 3D reference interaction site model (3D-RISM) statistical-mechanical solvation theory, with a well tested water model and a new united atom cyclohexane model, to calculate partition coefficients for the SAMPL5 dataset. The cyclohexane model performed well in training and testing (R=0.98 for amino acid neutral side chain analogues) but only if a parameterized solvation free energy correction was used. In contrast, the same protocol, using single solute conformations, performed poorly on the SAMPL5 dataset, obtaining R=0.73 compared to the reference partition coefficients, likely due to the much larger solute sizes. Including solute conformational sampling through molecular dynamics coupled with 3D-RISM (MD/3D-RISM) improved agreement with the reference calculation to R=0.93. Since our initial calculations only considered partition coefficients and not distribution coefficients, solute sampling provided little benefit comparing against experiment, where ionized and tautomer states are more important. Applying a simple pK_{ {a}} correction improved agreement with experiment from R=0.54 to R=0.66, despite a small number of outliers. Better agreement is possible by accounting for tautomers and improving the ionization correction.

  15. SAMPL5: 3D-RISM partition coefficient calculations with partial molar volume corrections and solute conformational sampling.

    Science.gov (United States)

    Luchko, Tyler; Blinov, Nikolay; Limon, Garrett C; Joyce, Kevin P; Kovalenko, Andriy

    2016-11-01

    Implicit solvent methods for classical molecular modeling are frequently used to provide fast, physics-based hydration free energies of macromolecules. Less commonly considered is the transferability of these methods to other solvents. The Statistical Assessment of Modeling of Proteins and Ligands 5 (SAMPL5) distribution coefficient dataset and the accompanying explicit solvent partition coefficient reference calculations provide a direct test of solvent model transferability. Here we use the 3D reference interaction site model (3D-RISM) statistical-mechanical solvation theory, with a well tested water model and a new united atom cyclohexane model, to calculate partition coefficients for the SAMPL5 dataset. The cyclohexane model performed well in training and testing ([Formula: see text] for amino acid neutral side chain analogues) but only if a parameterized solvation free energy correction was used. In contrast, the same protocol, using single solute conformations, performed poorly on the SAMPL5 dataset, obtaining [Formula: see text] compared to the reference partition coefficients, likely due to the much larger solute sizes. Including solute conformational sampling through molecular dynamics coupled with 3D-RISM (MD/3D-RISM) improved agreement with the reference calculation to [Formula: see text]. Since our initial calculations only considered partition coefficients and not distribution coefficients, solute sampling provided little benefit comparing against experiment, where ionized and tautomer states are more important. Applying a simple [Formula: see text] correction improved agreement with experiment from [Formula: see text] to [Formula: see text], despite a small number of outliers. Better agreement is possible by accounting for tautomers and improving the ionization correction.

  16. Mutually unbiased bases and trinary operator sets for N qutrits

    International Nuclear Information System (INIS)

    Lawrence, Jay

    2004-01-01

    A compete orthonormal basis of N-qutrit unitary operators drawn from the Pauli group consists of the identity and 9 N -1 traceless operators. The traceless ones partition into 3 N +1 maximally commuting subsets (MCS's) of 3 N -1 operators each, whose joint eigenbases are mutually unbiased. We prove that Pauli factor groups of order 3 N are isomorphic to all MCS's and show how this result applies in specific cases. For two qutrits, the 80 traceless operators partition into 10 MCS's. We prove that 4 of the corresponding basis sets must be separable, while 6 must be totally entangled (and Bell-like). For three qutrits, 728 operators partition into 28 MCS's with less rigid structure, allowing for the coexistence of separable, partially entangled, and totally entangled (GHZ-like) bases. However a minimum of 16 GHZ-like bases must occur. Every basis state is described by an N-digit trinary number consisting of the eigenvalues of N observables constructed from the corresponding MCS

  17. Evidence of niche partitioning under ontogenetic influences among three morphologically similar siluriformes in small subtropical streams.

    Directory of Open Access Journals (Sweden)

    Karine Orlandi Bonato

    Full Text Available Ontogenetic influences in patterns of niche breadth and feeding overlap were investigated in three species of Siluriformes (Heptapterus sp., Rhamdia quelen and Trichomycterus poikilos aiming at understanding the species coexistence. Samplings were conducted bimonthly by electrofishing technique from June/2012 to June/2013 in ten streams of the northwestern state of Rio Grande do Sul, Brazil. The stomach contents of 1,948 individuals were analyzed by volumetric method, with 59 food items identified. In general Heptapterus sp. consumed a high proportion of Aegla sp., terrestrial plant remains and Megaloptera; R. quelen consumed fish, and Oligochaeta, followed by Aegla sp.; while the diet of T. poikilos was based on Simuliidae, Ephemeroptera and Trichoptera. Specie segregation was observed in the NMDS. Through PERMANOVA analysis feeding differences among species, and between a combination of species plus size classes were observed. IndVal showed which items were indicators of these differences. Niche breadth values were high for all species. The niche breadth values were low only for the larger size of R. quelen and Heptapterus sp. while T. poikilos values were more similar. Overall the species were a low feeding overlap values. The higher frequency of high feeding overlap was observed for interaction between Heptapterus sp. and T. poikilos. The null model confirmed the niche partitioning between the species. The higher frequency of high and intermediate feeding overlap values were reported to smaller size classes. The null model showed resource sharing between the species/size class. Therefore, overall species showed a resource partitioning because of the use of occasional items. However, these species share resources mainly in the early ontogenetic stages until the emphasized change of morphological characteristics leading to trophic niche expansion and the apparent segregation observed.

  18. Sound Diffraction Around Movable Partitions in Teaching Spaces. Education Building Report 1.

    Science.gov (United States)

    Choudhury, N. K. D.

    This study concerns the diffraction of sound around flexible partitions used in teaching spaces. It includes a comprehensive study of the acoustical conditions in several school buildings in India, Malaysia, Singapore, and Sri Lanka. The noise reduction properties of some typical partitions the minimum height of the partition between two teaching…

  19. The reference frame for encoding and retention of motion depends on stimulus set size.

    Science.gov (United States)

    Huynh, Duong; Tripathy, Srimant P; Bedell, Harold E; Öğmen, Haluk

    2017-04-01

    The goal of this study was to investigate the reference frames used in perceptual encoding and storage of visual motion information. In our experiments, observers viewed multiple moving objects and reported the direction of motion of a randomly selected item. Using a vector-decomposition technique, we computed performance during smooth pursuit with respect to a spatiotopic (nonretinotopic) and to a retinotopic component and compared them with performance during fixation, which served as the baseline. For the stimulus encoding stage, which precedes memory, we found that the reference frame depends on the stimulus set size. For a single moving target, the spatiotopic reference frame had the most significant contribution with some additional contribution from the retinotopic reference frame. When the number of items increased (Set Sizes 3 to 7), the spatiotopic reference frame was able to account for the performance. Finally, when the number of items became larger than 7, the distinction between reference frames vanished. We interpret this finding as a switch to a more abstract nonmetric encoding of motion direction. We found that the retinotopic reference frame was not used in memory. Taken together with other studies, our results suggest that, whereas a retinotopic reference frame may be employed for controlling eye movements, perception and memory use primarily nonretinotopic reference frames. Furthermore, the use of nonretinotopic reference frames appears to be capacity limited. In the case of complex stimuli, the visual system may use perceptual grouping in order to simplify the complexity of stimuli or resort to a nonmetric abstract coding of motion information.

  20. The part-frequency matrices of a partition

    Directory of Open Access Journals (Sweden)

    William J. Keith

    2016-09-01

    Full Text Available A new combinatorial object is introduced, the part-frequency matrix sequence of a partition, whichis elementary to describe and is naturally motivated by Glaisher’s bijection. We prove results thatsuggest surprising usefulness for such a simple tool, including the existence of a related statistic thatrealizes every possible Ramanujan-type congruence for the partition function. To further exhibit itsresearch utility, we give an easy generalization of a theorem of Andrews, Dixit and Yee [1] on the mocktheta functions. Throughout, we state a number of observations and questions that can motivate anarray of investigations.

  1. Development of a test system for high level liquid waste partitioning

    OpenAIRE

    Duan Wu H.; Chen Jing; Wang Jian C.; Wang Shu W.; Wang Xing H.

    2015-01-01

    The partitioning and transmutation strategy has increasingly attracted interest for the safe treatment and disposal of high level liquid waste, in which the partitioning of high level liquid waste is one of the critical technical issues. An improved total partitioning process, including a tri-alkylphosphine oxide process for the removal of actinides, a crown ether strontium extraction process for the removal of strontium, and a calixcrown ether cesium extra...

  2. Siderophile Volatile Element Partitioning during Core Formation.

    Science.gov (United States)

    Loroch, D. C.; Hackler, S.; Rohrbach, A.; Klemme, S.

    2017-12-01

    Since the nineteen sixties it is known, that the Earth's mantle is depleted relative to CI chondrite in numerous elements as a result of accretion and core-mantle differentiation. Additionally, if we take the chondritic composition as the initial solar nebular element abundances, the Earth lacks 85 % of K and up to 98 % of other volatiles. However one potentially very important group of elements has received considerably less attention in this context and these elements are the siderophile but volatile elements (SVEs). SVEs perhaps provide important information regarding the timing of volatile delivery to Earth. Especially for the SVEs the partitioning between metal melt and silicate melt (Dmetal/silicate) at core formation conditions is poorly constrained, never the less they are very important for most of the core formation models. This study is producing new metal-silicate partitioning data for a wide range of SVEs (S, Se, Te, Tl, Ag, As, Au, Cd, Bi, Pb, Sn, Cu, Ge, Zn, In and Ga) with a focus on the P, T and fO2dependencies. The initial hypothesis that we are aiming to test uses the accretion of major portions of volatile elements while the core formation was still active. The key points of this study are: - What are the effects of P, T and fO2 on SVE metal-silicate partioning? - What is the effect of compositional complexity on SVE metal-silicate partioning? - How can SVE's D-values fit into current models of core formation? The partitioning experiments will be performed using a Walker type multi anvil apparatus in a pressure range between 10 and 20 GPa and temperatures of 1700 up to 2100 °C. To determine the Dmetal/silicate values we are using a field emission high-resolution JEOL JXA-8530F EPMA for major elements and a Photon Machines Analyte G2 Excimer laser (193 nm) ablation system coupled to a Thermo Fisher Element 2 single-collector ICP-MS (LA-ICP-MS) for the trace elements. We recently finished the first sets of experiments and can provide the

  3. Food and disturbance effects on Arctic benthic biomass and production size spectra

    Science.gov (United States)

    Górska, Barbara; Włodarska-Kowalczuk, Maria

    2017-03-01

    Body size is a fundamental biological unit that is closely coupled to key ecological properties and processes. At the community level, changes in size distributions may influence energy transfer pathways in benthic food webs and ecosystem carbon cycling; nevertheless they remain poorly explored in benthic systems, particularly in the polar regions. Here, we present the first assessment of the patterns of benthic biomass size spectra in Arctic coastal sediments and explore the effects of glacial disturbance and food availability on the partitioning of biomass and secondary productivity among size-defined components of benthic communities. The samples were collected in two Arctic fjords off west Spitsbergen (76 and 79°N), at 6 stations that represent three regimes of varying food availability (indicated by chlorophyll a concentration in the sediments) and glacial sedimentation disturbance intensity (indicated by sediment accumulation rates). The organisms were measured using image analysis to assess the biovolume, biomass and the annual production of each individual. The shape of benthic biomass size spectra at most stations was bimodal, with the location of a trough and peaks similar to those previously reported in lower latitudes. In undisturbed sediments macrofauna comprised 89% of the total benthic biomass and 56% of the total production. The lower availability of food resources seemed to suppress the biomass and secondary production across the whole size spectra (a 6-fold decrease in biomass and a 4-fold decrease in production in total) rather than reshape the spectrum. At locations where poor nutritional conditions were coupled with disturbance, the biomass was strongly reduced in selected macrofaunal size classes (class 10 and 11), while meiofaunal biomass and production were much higher, most likely due to a release from macrofaunal predation and competition pressure. As a result, the partitioning of benthic biomass and production shifted towards meiofauna

  4. Anion and cation partitioning between olivine, plagioclase phenocrysts and the host magma

    International Nuclear Information System (INIS)

    Yurimoto, Hisayoshi; Sueno, Shigeho

    1984-01-01

    Partition coefficients for -1, -2, -3, +1, +2, +3, +4 and +5 valent ions between the groundmass of tholeiite basalt and coexisting olivine and plagioclase phenocrysts from the Mid-Atlantic Ridge have been determined by secondary ion mass spectrometry. The present cation partitioning strongly supports the 'crystal structure control' mechanism. The partition coefficient for an anion is also under control of the crystal structure, so that each of the cation and anion positions in the crystal structure gives rise to a parabola-shaped peak on the partition coefficient vs. ionic radius diagram. (author)

  5. Basic plan of partitioning and transmutation technology development

    International Nuclear Information System (INIS)

    Ikegami, Tetsuo; Ozawa, Masaki

    2003-04-01

    Basic plan of partitioning and transmutation technology development has been made in more detail and concrete manner in terms of development goal, nuclides to be portioned and to be transmuted, and development schedule, based on the pre-evaluation results of the Research Evaluation Committee on Research and development of partitioning and transmutation technology for long life nuclides' held in August 2000. A step by step approach, consists of three steps, to reach the goal of partitioning and transmutation technology has been adopted under the recognition that the partitioning and transmutation technology development should be progressed steadily as a long term them. The first step is supposed to be able to attain within about 5 years by the present technology and on the extension of it. Such researches as collective separation of TRU, MA/Ln effective separation, and irradiation experiment of iodine and technetium. The second step is such a goal that is expected to be able to realize the engineering feasibility, within about 15 years, through the progress of science technology in future, although the engineering feasibility is not sufficiently foreseen at present. It will need revolutionary technology or breakthrough. Nuclides to be partitioned and to be transmuted have been selected in view points of 'radioactivity and radio-toxicity', 'geological repository', and 'effective utilization', corresponding to the each step of the development goal. Collaboration with other research organizations and with universities in the world should be pursued. Especially, such collaborations with France, with which information exchange on JOYO/PHENIX irradiation experiments is progressing, and with USA, which has recently developed positive activities in this field, are strongly expected. (author)

  6. Partitioning of monomethylmercury between freshwater algae and water.

    Science.gov (United States)

    Miles, C J; Moye, H A; Phlips, E J; Sargent, B

    2001-11-01

    Phytoplankton-water monomethylmercury (MeHg) partition constants (KpI) have been determined in the laboratory for two green algae Selenastrum capricornutum and Cosmarium botrytis, the blue-green algae Schizothrix calcicola, and the diatom Thallasiosira spp., algal species that are commonly found in natural surface waters. Two methods were used to determine KpI, the Freundlich isotherm method and the flow-through/dialysis bag method. Both methods yielded KpI values of about 10(6.6) for S. capricornutum and were not significantly different. The KpI for the four algae studied were similar except for Schizothrix, which was significantly lower than S. capricornutum. The KpI for MeHg and S. capricornutum (exponential growth) was not significantly different in systems with predominantly MeHgOH or MeHgCl species. This is consistent with other studies that show metal speciation controls uptake kinetics, but the reactivity with intracellular components controls steady-state concentrations. Partitioning constants determined with exponential and stationary phase S. capricornutum cells at the same conditions were not significantly different, while the partitioning constant for exponential phase, phosphorus-limited cells was significantly lower, suggesting that P-limitation alters the ecophysiology of S. capricornutum sufficiently to impact partitioning, which may then ultimately affect mercury levels in higher trophic species.

  7. Reproductive Interference and Niche Partitioning in Aphidophagous Insects

    Directory of Open Access Journals (Sweden)

    Suzuki Noriyuki

    2016-01-01

    Full Text Available The range and quality of prey species differ greatly among closely related species of predators. However, the factors responsible for this diversified niche utilization are unclear. This is because the predation and resource competition do not always prevent species coexistence. In this paper, we present evidence in support of reproductive interference as a driver of niche partitioning, focusing on aphidophagous insect. Firstly, we present closely related generalist and specialist species pairs in aphidophagous lacewings to compare the reproductive interference hypothesis with two other hypotheses that have been proposed to explain niche partitioning in lacewings and sympatric speciation through host race formation and sexual selection. Secondly, we present a case study that shows how reproductive interference can drive niche partitioning in sibling ladybird species. Thirdly, we show that many ladybird genera include species inhabiting the same region but having different food and habitat preferences, raising the possibility that reproductive interference might occur in these groups. Finally, we show that intraguild predation cannot always explain the niche partitioning in aphidophagous insects including hoverflies and parasitoids. On the basis of the evidence presented, we urge that future studies investigating predator communities should take account of the role of reproductive interference.

  8. Time Domain Partitioning of Electricity Production Cost Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Barrows, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hummon, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jones, W. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hale, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-01-01

    Production cost models are often used for planning by simulating power system operations over long time horizons. The simulation of a day-ahead energy market can take several weeks to compute. Tractability improvements are often made through model simplifications, such as: reductions in transmission modeling detail, relaxation of commitment variable integrality, reductions in cost modeling detail, etc. One common simplification is to partition the simulation horizon so that weekly or monthly horizons can be simulated in parallel. However, horizon partitions are often executed with overlap periods of arbitrary and sometimes zero length. We calculate the time domain persistence of historical unit commitment decisions to inform time domain partitioning of production cost models. The results are implemented using PLEXOS production cost modeling software in an HPC environment to improve the computation time of simulations while maintaining solution integrity.

  9. Item Anomaly Detection Based on Dynamic Partition for Time Series in Recommender Systems.

    Science.gov (United States)

    Gao, Min; Tian, Renli; Wen, Junhao; Xiong, Qingyu; Ling, Bin; Yang, Linda

    2015-01-01

    In recent years, recommender systems have become an effective method to process information overload. However, recommendation technology still suffers from many problems. One of the problems is shilling attacks-attackers inject spam user profiles to disturb the list of recommendation items. There are two characteristics of all types of shilling attacks: 1) Item abnormality: The rating of target items is always maximum or minimum; and 2) Attack promptness: It takes only a very short period time to inject attack profiles. Some papers have proposed item anomaly detection methods based on these two characteristics, but their detection rate, false alarm rate, and universality need to be further improved. To solve these problems, this paper proposes an item anomaly detection method based on dynamic partitioning for time series. This method first dynamically partitions item-rating time series based on important points. Then, we use chi square distribution (χ2) to detect abnormal intervals. The experimental results on MovieLens 100K and 1M indicate that this approach has a high detection rate and a low false alarm rate and is stable toward different attack models and filler sizes.

  10. Item Anomaly Detection Based on Dynamic Partition for Time Series in Recommender Systems

    Science.gov (United States)

    Gao, Min; Tian, Renli; Wen, Junhao; Xiong, Qingyu; Ling, Bin; Yang, Linda

    2015-01-01

    In recent years, recommender systems have become an effective method to process information overload. However, recommendation technology still suffers from many problems. One of the problems is shilling attacks-attackers inject spam user profiles to disturb the list of recommendation items. There are two characteristics of all types of shilling attacks: 1) Item abnormality: The rating of target items is always maximum or minimum; and 2) Attack promptness: It takes only a very short period time to inject attack profiles. Some papers have proposed item anomaly detection methods based on these two characteristics, but their detection rate, false alarm rate, and universality need to be further improved. To solve these problems, this paper proposes an item anomaly detection method based on dynamic partitioning for time series. This method first dynamically partitions item-rating time series based on important points. Then, we use chi square distribution (χ2) to detect abnormal intervals. The experimental results on MovieLens 100K and 1M indicate that this approach has a high detection rate and a low false alarm rate and is stable toward different attack models and filler sizes. PMID:26267477

  11. Handling Data Skew in MapReduce Cluster by Using Partition Tuning

    Directory of Open Access Journals (Sweden)

    Yufei Gao

    2017-01-01

    Full Text Available The healthcare industry has generated large amounts of data, and analyzing these has emerged as an important problem in recent years. The MapReduce programming model has been successfully used for big data analytics. However, data skew invariably occurs in big data analytics and seriously affects efficiency. To overcome the data skew problem in MapReduce, we have in the past proposed a data processing algorithm called Partition Tuning-based Skew Handling (PTSH. In comparison with the one-stage partitioning strategy used in the traditional MapReduce model, PTSH uses a two-stage strategy and the partition tuning method to disperse key-value pairs in virtual partitions and recombines each partition in case of data skew. The robustness and efficiency of the proposed algorithm were tested on a wide variety of simulated datasets and real healthcare datasets. The results showed that PTSH algorithm can handle data skew in MapReduce efficiently and improve the performance of MapReduce jobs in comparison with the native Hadoop, Closer, and locality-aware and fairness-aware key partitioning (LEEN. We also found that the time needed for rule extraction can be reduced significantly by adopting the PTSH algorithm, since it is more suitable for association rule mining (ARM on healthcare data.

  12. Genus two partition functions of extremal conformal field theories

    International Nuclear Information System (INIS)

    Gaiotto, Davide; Yin Xi

    2007-01-01

    Recently Witten conjectured the existence of a family of 'extremal' conformal field theories (ECFTs) of central charge c = 24k, which are supposed to be dual to three-dimensional pure quantum gravity in AdS 3 . Assuming their existence, we determine explicitly the genus two partition functions of k = 2 and k = 3 ECFTs, using modular invariance and the behavior of the partition function in degenerating limits of the Riemann surface. The result passes highly nontrivial tests and in particular provides a piece of evidence for the existence of the k = 3 ECFT. We also argue that the genus two partition function of ECFTs with k ≤ 10 are uniquely fixed (if they exist)

  13. ParABS Systems of the Four Replicons of Burkholderia cenocepacia: New Chromosome Centromeres Confer Partition Specificity†

    Science.gov (United States)

    Dubarry, Nelly; Pasta, Franck; Lane, David

    2006-01-01

    Most bacterial chromosomes carry an analogue of the parABS systems that govern plasmid partition, but their role in chromosome partition is ambiguous. parABS systems might be particularly important for orderly segregation of multipartite genomes, where their role may thus be easier to evaluate. We have characterized parABS systems in Burkholderia cenocepacia, whose genome comprises three chromosomes and one low-copy-number plasmid. A single parAB locus and a set of ParB-binding (parS) centromere sites are located near the origin of each replicon. ParA and ParB of the longest chromosome are phylogenetically similar to analogues in other multichromosome and monochromosome bacteria but are distinct from those of smaller chromosomes. The latter form subgroups that correspond to the taxa of their hosts, indicating evolution from plasmids. The parS sites on the smaller chromosomes and the plasmid are similar to the “universal” parS of the main chromosome but with a sequence specific to their replicon. In an Escherichia coli plasmid stabilization test, each parAB exhibits partition activity only with the parS of its own replicon. Hence, parABS function is based on the independent partition of individual chromosomes rather than on a single communal system or network of interacting systems. Stabilization by the smaller chromosome and plasmid systems was enhanced by mutation of parS sites and a promoter internal to their parAB operons, suggesting autoregulatory mechanisms. The small chromosome ParBs were found to silence transcription, a property relevant to autoregulation. PMID:16452432

  14. Partitioning of TRU elements from Chinese HLLW

    International Nuclear Information System (INIS)

    Song Chongli; Zhu Yongjun

    1994-04-01

    The partitioning of TRU elements from the Chinese HLLW is feasible. The required D.F. values for producing a waste suitable for land disposal are given. The TRPO process developed in China could be used for this purpose. The research and development of the TRPO process is summarized and the general flowsheet is given. The Chinese HLLW has very high salt concentration. It causes the formation of third phase when contacted with TRPO extractant. The third phase would disappear by diluting the Chinese HLLW to 2∼3 times before extraction. The preliminary experiment shows very attractive results. The separation of Sr and Cs from the Chinese HLLW is also possible. The process is being studied. The partitioning of TRU elements and long lived ratio-nuclides from the Chinese HLLW provides an alternative method for its disposal. The partitioning of the Chinese HLLW could greatly reduce the waste volume, that is needed to be vitrified and to be disposed in to the deep repository, and then would drastically save the overall waste disposal cost

  15. Radionuclide Partitioning in an Underground Nuclear Test Cavity

    Energy Technology Data Exchange (ETDEWEB)

    Rose, T P; Hu, Q; Zhao, P; Conrado, C L; Dickerson, R; Eaton, G F; Kersting, A B; Moran, J E; Nimz, G; Powell, B A; Ramon, E C; Ryerson, F J; Williams, R W; Wooddy, P T; Zavarin, M

    2009-01-09

    In 2004, a borehole was drilled into the 1983 Chancellor underground nuclear test cavity to investigate the distribution of radionuclides within the cavity. Sidewall core samples were collected from a range of depths within the re-entry hole and two sidetrack holes. Upon completion of drilling, casing was installed and a submersible pump was used to collect groundwater samples. Test debris and groundwater samples were analyzed for a variety of radionuclides including the fission products {sup 99}Tc, {sup 125}Sb, {sup 129}I, {sup 137}Cs, and {sup 155}Eu, the activation products {sup 60}Co, {sup 152}Eu, and {sup 154}Eu, and the actinides U, Pu, and Am. In addition, the physical and bulk chemical properties of the test debris were characterized using Scanning Electron Microscopy (SEM) and Electron Microprobe measurements. Analytical results were used to evaluate the partitioning of radionuclides between the melt glass, rubble, and groundwater phases in the Chancellor test cavity. Three comparative approaches were used to calculate partitioning values, though each method could not be applied to every nuclide. These approaches are based on: (1) the average Area 19 inventory from Bowen et al. (2001); (2) melt glass, rubble, and groundwater mass estimates from Zhao et al. (2008); and (3) fission product mass yield data from England and Rider (1994). The U and Pu analyses of the test debris are classified and partitioning estimates for these elements were calculated directly from the classified Miller et al. (2002) inventory for the Chancellor test. The partitioning results from this study were compared to partitioning data that were previously published by the IAEA (1998). Predictions of radionuclide distributions from the two studies are in agreement for a majority of the nuclides under consideration. Substantial differences were noted in the partitioning values for {sup 99}Tc, {sup 125}Sb, {sup 129}I, and uranium. These differences are attributable to two factors

  16. Sigma set scattering equations in nuclear reaction theory

    International Nuclear Information System (INIS)

    Kowalski, K.L.; Picklesimer, A.

    1982-01-01

    The practical applications of partially summed versions of the Rosenberg equations involving only special subsets (sigma sets) of the physical amplitudes are investigated with special attention to the Pauli principle. The requisite properties of the transformations from the pair labels to the set of partitions labeling the sigma set of asymptotic channels are established. New, well-defined, scattering integral equations for the antisymmetrized transition operators are found which possess much less coupling among the physically distinct channels than hitherto expected for equations with kernels of equal complexity. In several cases of physical interest in nuclear physics, a single connected-kernel equation is obtained for the relevant antisymmetrized elastic scattering amplitude

  17. Developing Key Parameters for Green Performance of Partition Wall Blocks

    Directory of Open Access Journals (Sweden)

    Goh Cheng Siew

    2016-01-01

    Full Text Available To promote sustainable construction, it is important to consider green performance of construction materials throughout the life cycle. Selecting inappropriate materials could not only affect the functional performance but also preclude the achievement of green building performance as a whole. Green performance of construction materials has therefore been one of the primary considerations of green building assessment systems. Using partition wall blocks as an example, this paper examines green performance of building materials primarily from the cradle to gate boundaries. Nine key parameters are proposed for the green performance of partition wall blocks. Apart from environmental features, technical performance of partition wall blocks is also taken into consideration since it is the determinant of the lifecycle performance. This paper offers a roadmap to decision makers to make environmentally responsible choices for their materials of internal walls and partitions, and hence provides a potential sustainable solution for green buildings.

  18. Partition functions. I. Improved partition functions and thermodynamic quantities for normal, equilibrium, and ortho and para molecular hydrogen

    Science.gov (United States)

    Popovas, A.; Jørgensen, U. G.

    2016-11-01

    Context. Hydrogen is the most abundant molecule in the Universe. Its thermodynamic quantities dominate the physical conditions in molecular clouds, protoplanetary disks, etc. It is also of high interest in plasma physics. Therefore thermodynamic data for molecular hydrogen have to be as accurate as possible in a wide temperature range. Aims: We here rigorously show the shortcomings of various simplifications that are used to calculate the total internal partition function. These shortcomings can lead to errors of up to 40 percent or more in the estimated partition function. These errors carry on to calculations of thermodynamic quantities. Therefore a more complicated approach has to be taken. Methods: Seven possible simplifications of various complexity are described, together with advantages and disadvantages of direct summation of experimental values. These were compared to what we consider the most accurate and most complete treatment (case 8). Dunham coefficients were determined from experimental and theoretical energy levels of a number of electronically excited states of H2. Both equilibrium and normal hydrogen was taken into consideration. Results: Various shortcomings in existing calculations are demonstrated, and the reasons for them are explained. New partition functions for equilibrium, normal, and ortho and para hydrogen are calculated and thermodynamic quantities are reported for the temperature range 1-20 000 K. Our results are compared to previous estimates in the literature. The calculations are not limited to the ground electronic state, but include all bound and quasi-bound levels of excited electronic states. Dunham coefficients of these states of H2 are also reported. Conclusions: For most of the relevant astrophysical cases it is strongly advised to avoid using simplifications, such as a harmonic oscillator and rigid rotor or ad hoc summation limits of the eigenstates to estimate accurate partition functions and to be particularly careful when

  19. Predicting solute partitioning in lipid bilayers: Free energies and partition coefficients from molecular dynamics simulations and COSMOmic

    Science.gov (United States)

    Jakobtorweihen, S.; Zuniga, A. Chaides; Ingram, T.; Gerlach, T.; Keil, F. J.; Smirnova, I.

    2014-07-01

    Quantitative predictions of biomembrane/water partition coefficients are important, as they are a key property in pharmaceutical applications and toxicological studies. Molecular dynamics (MD) simulations are used to calculate free energy profiles for different solutes in lipid bilayers. How to calculate partition coefficients from these profiles is discussed in detail and different definitions of partition coefficients are compared. Importantly, it is shown that the calculated coefficients are in quantitative agreement with experimental results. Furthermore, we compare free energy profiles from MD simulations to profiles obtained by the recent method COSMOmic, which is an extension of the conductor-like screening model for realistic solvation to micelles and biomembranes. The free energy profiles from these molecular methods are in good agreement. Additionally, solute orientations calculated with MD and COSMOmic are compared and again a good agreement is found. Four different solutes are investigated in detail: 4-ethylphenol, propanol, 5-phenylvaleric acid, and dibenz[a,h]anthracene, whereby the latter belongs to the class of polycyclic aromatic hydrocarbons. The convergence of the free energy profiles from biased MD simulations is discussed and the results are shown to be comparable to equilibrium MD simulations. For 5-phenylvaleric acid the influence of the carboxyl group dihedral angle on free energy profiles is analyzed with MD simulations.

  20. Predicting solute partitioning in lipid bilayers: Free energies and partition coefficients from molecular dynamics simulations and COSMOmic

    International Nuclear Information System (INIS)

    Jakobtorweihen, S.; Ingram, T.; Gerlach, T.; Smirnova, I.; Zuniga, A. Chaides; Keil, F. J.

    2014-01-01

    Quantitative predictions of biomembrane/water partition coefficients are important, as they are a key property in pharmaceutical applications and toxicological studies. Molecular dynamics (MD) simulations are used to calculate free energy profiles for different solutes in lipid bilayers. How to calculate partition coefficients from these profiles is discussed in detail and different definitions of partition coefficients are compared. Importantly, it is shown that the calculated coefficients are in quantitative agreement with experimental results. Furthermore, we compare free energy profiles from MD simulations to profiles obtained by the recent method COSMOmic, which is an extension of the conductor-like screening model for realistic solvation to micelles and biomembranes. The free energy profiles from these molecular methods are in good agreement. Additionally, solute orientations calculated with MD and COSMOmic are compared and again a good agreement is found. Four different solutes are investigated in detail: 4-ethylphenol, propanol, 5-phenylvaleric acid, and dibenz[a,h]anthracene, whereby the latter belongs to the class of polycyclic aromatic hydrocarbons. The convergence of the free energy profiles from biased MD simulations is discussed and the results are shown to be comparable to equilibrium MD simulations. For 5-phenylvaleric acid the influence of the carboxyl group dihedral angle on free energy profiles is analyzed with MD simulations

  1. Experimental study of radium partitioning between anorthite and melt at 1 atm

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S; Burnett, D; Asimow, P; Phinney, D; Hutcheon, I

    2007-03-08

    We present the first experimental radium mineral/melt partitioning data, specifically between anorthite and a CMAS melt at atmospheric pressure. Ion microprobe measurement of coexisting anorthite and glass phases produces a molar D{sub Ra} = 0.040 {+-} 0.006 and D{sub Ra}/D{sub Ba} = 0.23 {+-} 0.05 at 1400 C. Our results indicate that lattice strain partitioning models fit the divalent (Ca, Sr, Ba, Ra) partition coefficient data of this study well, supporting previous work on crustal melting and magma chamber dynamics that has relied on such models to approximate radium partitioning behavior in the absence of experimentally determined values.

  2. Development of long-lived radionuclide partitioning technology

    International Nuclear Information System (INIS)

    Lee, Eil Hee; Kwon, S. G.; Yang, H. B.

    2001-04-01

    This project was aimed at the development of an optimal process that could get recovery yields of 99% for Am and Np and 90% for Tc from a simulated radioactive waste and the improvements of unit processes. The performed works are summarized, as follows. 1) The design and the establishment of a laboratory-scale partitioning process were accomplished, and the interfacial conditions between each unit process were determined. An optimal flow diagram for long-lived radionuclide partitioning process was suggested. 2) In improvements of unit processes, a) Behaviors of the co-extraction and sequential separation for residual U, Np and Tc(/Re) by chemical and electrochemical methods were examined. b) Conditions for co-extraction of Am/RE, and selective stripping of Am with metal containing extractant and a mixed extractant were decided. c) Characteristics of adsorption and elution by ion exchange chromatography and extraction chromatography methods were analysed. d) The simulation codes for long-lived radionuclide partitioning were gathered. and reaction equations were numerically formulated. 3) An existing γ-lead cell was modified the α-γ cells for treatment of long-lived radioactive materials. 4) As the applications of new separation technologies, a) Behaviors of photo reductive precipitation for Am/RE were investigated, b) Conditions for selective extraction and stripping of Am with pyridine series extractants were established. All results will be used as the fundamental data for establishment of partitioning process and radiochemical test of long-lived radionuclides recovery technology to be performed in the next stage

  3. Spatial and Temporal Variations in Slip Partitioning During Oblique Convergence Experiments

    Science.gov (United States)

    Beyer, J. L.; Cooke, M. L.; Toeneboehn, K.

    2017-12-01

    Physical experiments of oblique convergence in wet kaolin demonstrate the development of slip partitioning, where two faults accommodate strain via different slip vectors. In these experiments, the second fault forms after the development of the first fault. As one strain component is relieved by one fault, the local stress field then favors the development of a second fault with different slip sense. A suite of physical experiments reveals three styles of slip partitioning development controlled by the convergence angle and presence of a pre-existing fault. In experiments with low convergence angles, strike-slip faults grow prior to reverse faults (Type 1) regardless of whether the fault is precut or not. In experiments with moderate convergence angles, slip partitioning is dominantly controlled by the presence of a pre-existing fault. In all experiments, the primarily reverse fault forms first. Slip partitioning then develops with the initiation of strike-slip along the precut fault (Type 2) or growth of a secondary reverse fault where the first fault is steepest. Subsequently, the slip on the first fault transitions to primarily strike-slip (Type 3). Slip rates and rakes along the slip partitioned faults for both precut and uncut experiments vary temporally, suggesting that faults in these slip-partitioned systems are constantly adapting to the conditions produced by slip along nearby faults in the system. While physical experiments show the evolution of slip partitioning, numerical simulations of the experiments provide information about both the stress and strain fields, which can be used to compute the full work budget, providing insight into the mechanisms that drive slip partitioning. Preliminary simulations of precut experiments show that strain energy density (internal work) can be used to predict fault growth, highlighting where fault growth can reduce off-fault deformation in the physical experiments. In numerical simulations of uncut experiments with a

  4. Review of partitioning proposals for spent nuclear fuels

    International Nuclear Information System (INIS)

    Bowersox, D.F.

    1976-07-01

    The initial phase of a study about recovery of valuable fission products from spent nuclear fuels has been to review various partitioning proposals. This report briefly describes the aqueous Purex process, the salt transport process, melt refining, fluoride volatility process, and gravimetric separations. All these processes appear to be possible technically, but further research will be necessary to determine which are most feasible. This review includes general recommendations for experimental research and development of several partitioning options

  5. Assimilate partitioning in avocado, Persea americana

    International Nuclear Information System (INIS)

    Finazzo, S.; Davenport, T.L.

    1986-01-01

    Assimilate partitioning is being studied in avocado, Persea americana cv. Millborrow in relation to fruit set. Single leaves on girdled branches of 10 year old trees were radiolabeled for 1 hr with 13μCi of 14 CO 2 . The source leaves were sampled during the experiment to measure translocation rates. At harvest the sink tissues were dissected and the incorporated radioactivity was measured. The translocation of 14 C-labelled compounds to other leaves was minimal. Incorporation of label into fruitlets varied with the tissue and the stage of development. Sink (fruitlets) nearest to the labelled leaf and sharing the same phyllotaxy incorporated the most 14 C. Source leaves for single non-abscising fruitlets retained 3X more 14 C-labelled compounds than did source leaves for 2 or more fruitlets at 31 hrs. post-labelling. Export of label decreased appreciably when fruitlets abscised. If fruitlets abscised within 4 days of labeling then the translocation pattern was similar to the pattern for single fruitlets. If the fruitlet abscised later, the translocation pattern was intermediate between the single and double fruitlet pattern

  6. Tall swards and small grazers : competition, facilitation and coexistence of different-sized grazers

    NARCIS (Netherlands)

    Heuermann, N.

    2007-01-01

    Differences in body mass are assumed to be a major factor leading to resource partitioning and the reduction of competition between species within a guild. To study the effects of body mass on foraging behaviour of grazers independently of morphological adaptations we used intra-specific size

  7. Active control of sound transmission through a double panel partition

    Science.gov (United States)

    Sas, P.; Bao, C.; Augusztinovicz, F.; Desmet, W.

    1995-03-01

    The feasibility of improving the insertion loss of lightweight double panel partitions by using small loudspeakers as active noise control sources inside the air gap between both panels of the partition is investigated analytically, numerically and experimentally in this paper. A theoretical analysis of the mechanisms of the fluid-structure interaction of double panel structures is presented in order to gain insight into the physical phenomena underlying the behaviour of a coupled vibro-acoustic system controlled by active methods. The analysis, based on modal coupling theory, enables one to derive some qualitative predictions concerning the potentials and limitations of the proposed approach. The theoretical analysis is valid only for geometrically simple structures. For more complex geometries, numerical simulations are required. Therefore the potential use of active noise control inside double panel structures has been analyzed by using coupled finite element and boundary element methods. To verify the conclusions drawn from the theoretical analysis and the numerical calculation and, above all, to demonstrate the potential of the proposed approach, experiments have been conducted with a laboratory set-up. The performance of the proposed approach was evaluated in terms of relative insertion loss measurements. It is shown that a considerable improvement of the insertion loss has been achieved around the lightly damped resonances of the system for the frequency range investigated (60-220 Hz).

  8. Development of a test system for high level liquid waste partitioning

    Directory of Open Access Journals (Sweden)

    Duan Wu H.

    2015-01-01

    Full Text Available The partitioning and transmutation strategy has increasingly attracted interest for the safe treatment and disposal of high level liquid waste, in which the partitioning of high level liquid waste is one of the critical technical issues. An improved total partitioning process, including a tri-alkylphosphine oxide process for the removal of actinides, a crown ether strontium extraction process for the removal of strontium, and a calixcrown ether cesium extraction process for the removal of cesium, has been developed to treat Chinese high level liquid waste. A test system containing 72-stage 10-mm-diam annular centrifugal contactors, a remote sampling system, a rotor speed acquisition-monitoring system, a feeding system, and a video camera-surveillance system was successfully developed to carry out the hot test for verifying the improved total partitioning process. The test system has been successfully used in a 160 hour hot test using genuine high level liquid waste. During the hot test, the test system was stable, which demonstrated it was reliable for the hot test of the high level liquid waste partitioning.

  9. Maximal independent set graph partitions for representations of body-centered cubic lattices

    DEFF Research Database (Denmark)

    Erleben, Kenny

    2009-01-01

    corresponding to the leaves of a quad-tree thus has a smaller memory foot-print. The adjacency information in the graph relieves one from going up and down the quad-tree when searching for neighbors. This results in constant time complexities for refinement and coarsening operations.......A maximal independent set graph data structure for a body-centered cubic lattice is presented. Refinement and coarsening operations are defined in terms of set-operations resulting in robust and easy implementation compared to a quad-tree-based implementation. The graph only stores information...

  10. Particle size dependence of biogenic secondary organic aerosol molecular composition

    Science.gov (United States)

    Tu, Peijun; Johnston, Murray V.

    2017-06-01

    Formation of secondary organic aerosol (SOA) is initiated by the oxidation of volatile organic compounds (VOCs) in the gas phase whose products subsequently partition to the particle phase. Non-volatile molecules have a negligible evaporation rate and grow particles at their condensation rate. Semi-volatile molecules have a significant evaporation rate and grow particles at a much slower rate than their condensation rate. Particle phase chemistry may enhance particle growth if it transforms partitioned semi-volatile molecules into non-volatile products. In principle, changes in molecular composition as a function of particle size allow non-volatile molecules that have condensed from the gas phase (a surface-limited process) to be distinguished from those produced by particle phase reaction (a volume-limited process). In this work, SOA was produced by β-pinene ozonolysis in a flow tube reactor. Aerosol exiting the reactor was size-selected with a differential mobility analyzer, and individual particle sizes between 35 and 110 nm in diameter were characterized by on- and offline mass spectrometry. Both the average oxygen-to-carbon (O / C) ratio and carbon oxidation state (OSc) were found to decrease with increasing particle size, while the relative signal intensity of oligomers increased with increasing particle size. These results are consistent with oligomer formation primarily in the particle phase (accretion reactions, which become more favored as the volume-to-surface-area ratio of the particle increases). Analysis of a series of polydisperse SOA samples showed similar dependencies: as the mass loading increased (and average volume-to-surface-area ratio increased), the average O / C ratio and OSc decreased, while the relative intensity of oligomer ions increased. The results illustrate the potential impact that particle phase chemistry can have on biogenic SOA formation and the particle size range where this chemistry becomes important.

  11. Particle size dependence of biogenic secondary organic aerosol molecular composition

    Directory of Open Access Journals (Sweden)

    P. Tu

    2017-06-01

    Full Text Available Formation of secondary organic aerosol (SOA is initiated by the oxidation of volatile organic compounds (VOCs in the gas phase whose products subsequently partition to the particle phase. Non-volatile molecules have a negligible evaporation rate and grow particles at their condensation rate. Semi-volatile molecules have a significant evaporation rate and grow particles at a much slower rate than their condensation rate. Particle phase chemistry may enhance particle growth if it transforms partitioned semi-volatile molecules into non-volatile products. In principle, changes in molecular composition as a function of particle size allow non-volatile molecules that have condensed from the gas phase (a surface-limited process to be distinguished from those produced by particle phase reaction (a volume-limited process. In this work, SOA was produced by β-pinene ozonolysis in a flow tube reactor. Aerosol exiting the reactor was size-selected with a differential mobility analyzer, and individual particle sizes between 35 and 110 nm in diameter were characterized by on- and offline mass spectrometry. Both the average oxygen-to-carbon (O ∕ C ratio and carbon oxidation state (OSc were found to decrease with increasing particle size, while the relative signal intensity of oligomers increased with increasing particle size. These results are consistent with oligomer formation primarily in the particle phase (accretion reactions, which become more favored as the volume-to-surface-area ratio of the particle increases. Analysis of a series of polydisperse SOA samples showed similar dependencies: as the mass loading increased (and average volume-to-surface-area ratio increased, the average O ∕ C ratio and OSc decreased, while the relative intensity of oligomer ions increased. The results illustrate the potential impact that particle phase chemistry can have on biogenic SOA formation and the particle size range where this chemistry becomes

  12. Approximation methods for the partition functions of anharmonic systems

    International Nuclear Information System (INIS)

    Lew, P.; Ishida, T.

    1979-07-01

    The analytical approximations for the classical, quantum mechanical and reduced partition functions of the diatomic molecule oscillating internally under the influence of the Morse potential have been derived and their convergences have been tested numerically. This successful analytical method is used in the treatment of anharmonic systems. Using Schwinger perturbation method in the framework of second quantization formulism, the reduced partition function of polyatomic systems can be put into an expression which consists separately of contributions from the harmonic terms, Morse potential correction terms and interaction terms due to the off-diagonal potential coefficients. The calculated results of the reduced partition function from the approximation method on the 2-D and 3-D model systems agree well with the numerical exact calculations

  13. Timing Analysis of Mixed-Criticality Hard Real-Time Applications Implemented on Distributed Partitioned Architectures

    DEFF Research Database (Denmark)

    Marinescu, Sorin Ovidiu; Tamas-Selicean, Domitian; Acretoaie, Vlad

    In this paper we are interested in the timing analysis of mixed-criticality embedded real-time applications mapped on distributed heterogeneous architectures. Mixedcriticality tasks can be integrated onto the same architecture only if there is enough spatial and temporal separation among them. We...... in partitions using fixedpriority preemptive scheduling. We have extended the stateof- the-art algorithms for schedulability analysis to take into account the partitions. The proposed algorithm has been evaluated using several synthetic and real-life benchmarks....... consider that the separation is provided by partitioning, such that applications run in separate partitions, and each partition is allocated several time slots on a processor. Each partition can have its own scheduling policy. We are interested to determine the worst-case response times of tasks scheduled...

  14. A conjugate gradient method for the spectral partitioning of graphs

    NARCIS (Netherlands)

    Kruyt, Nicolaas P.

    1997-01-01

    The partitioning of graphs is a frequently occurring problem in science and engineering. The spectral graph partitioning method is a promising heuristic method for this class of problems. Its main disadvantage is the large computing time required to solve a special eigenproblem. Here a simple and

  15. Field determination and QSPR prediction of equilibrium-status soil/vegetation partition coefficient of PCDD/Fs.

    Science.gov (United States)

    Li, Li; Wang, Qiang; Qiu, Xinghua; Dong, Yian; Jia, Shenglan; Hu, Jianxin

    2014-07-15

    Characterizing pseudo equilibrium-status soil/vegetation partition coefficient KSV, the quotient of respective concentrations in soil and vegetation of a certain substance at remote background areas, is essential in ecological risk assessment, however few previous attempts have been made for field determination and developing validated and reproducible structure-based estimates. In this study, KSV was calculated based on measurements of seventeen 2,3,7,8-substituted PCDD/F congeners in soil and moss (Dicranum angustum), and rouzi grass (Thylacospermum caespitosum) of two background sites, Ny-Ålesund of the Arctic and Zhangmu-Nyalam region of the Tibet Plateau, respectively. By both fugacity modeling and stepwise regression of field data, the air-water partition coefficient (KAW) and aqueous solubility (SW) were identified as the influential physicochemical properties. Furthermore, validated quantitative structure-property relationship (QSPR) model was developed to extrapolate the KSV prediction to all 210 PCDD/F congeners. Molecular polarizability, molecular size and molecular energy demonstrated leading effects on KSV. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Helium-air exchange flows through partitioned opening and two-opening

    International Nuclear Information System (INIS)

    Kang, T. I.

    1997-01-01

    This paper describes experimental investigations of helium-air exchange flows through partitioned opening and two-opening. Such exchange flows may occur following rupture accident of stand pipe in high temperature engineering test reactor. A test vessel with the two types of small opening on top of test cylinder is used for experiments. An estimation method of mass increment is developed to measure the exchange flow rate. Upward flow of the helium and downward flow of the air in partitioned opening system interact out of entrance and exit of the opening. Therefore, an experiment with two-opening system is made to investigate effect of the fluids interaction of partitioned opening system. As a result of comparison of the exchange flow rates between two types of the opening system, it is demonstrated that the exchange flow rate of the two-opening system is larger than that of the partitioned opening system because of absence of the effect of fluids interaction. (author)

  17. An Efficient Technique for Hardware/Software Partitioning Process in Codesign

    Directory of Open Access Journals (Sweden)

    Imene Mhadhbi

    2016-01-01

    Full Text Available Codesign methodology deals with the problem of designing complex embedded systems, where automatic hardware/software partitioning is one key issue. The research efforts in this issue are focused on exploring new automatic partitioning methods which consider only binary or extended partitioning problems. The main contribution of this paper is to propose a hybrid FCMPSO partitioning technique, based on Fuzzy C-Means (FCM and Particle Swarm Optimization (PSO algorithms suitable for mapping embedded applications for both binary and multicores target architecture. Our FCMPSO optimization technique has been compared using different graphical models with a large number of instances. Performance analysis reveals that FCMPSO outperforms PSO algorithm as well as the Genetic Algorithm (GA, Simulated Annealing (SA, Ant Colony Optimization (ACO, and FCM standard metaheuristic based techniques and also hybrid solutions including PSO then GA, GA then SA, GA then ACO, ACO then SA, FCM then GA, FCM then SA, and finally ACO followed by FCM.

  18. The impact of aerosol composition on the particle to gas partitioning of reactive mercury.

    Science.gov (United States)

    Rutter, Andrew P; Schauer, James J

    2007-06-01

    A laboratory system was developed to study the gas-particle partitioning of reactive mercury (RM) as a function of aerosol composition in synthetic atmospheric particulate matter. The collection of RM was achieved by filter- and sorbent-based methods. Analyses of the RM collected on the filters and sorbents were performed using thermal extraction combined with cold vapor atomic fluorescence spectroscopy (CVAFS), allowing direct measurement of the RM load on the substrates. Laboratory measurements of the gas-particle partitioning coefficients of RM to atmospheric aerosol particles revealed a strong dependence on aerosol composition, with partitioning coefficients that varied by orders of magnitude depending on the composition of the particles. Particles of sodium nitrate and the chlorides of potassium and sodium had high partitioning coefficients, shifting the RM partitioning toward the particle phase, while ammonium sulfate, levoglucosan, and adipic acid caused the RM to partition toward the gas phase and, therefore, had partitioning coefficients that were lower by orders of magnitude.

  19. Optimizing Distributed Machine Learning for Large Scale EEG Data Set

    Directory of Open Access Journals (Sweden)

    M Bilal Shaikh

    2017-06-01

    Full Text Available Distributed Machine Learning (DML has gained its importance more than ever in this era of Big Data. There are a lot of challenges to scale machine learning techniques on distributed platforms. When it comes to scalability, improving the processor technology for high level computation of data is at its limit, however increasing machine nodes and distributing data along with computation looks as a viable solution. Different frameworks   and platforms are available to solve DML problems. These platforms provide automated random data distribution of datasets which miss the power of user defined intelligent data partitioning based on domain knowledge. We have conducted an empirical study which uses an EEG Data Set collected through P300 Speller component of an ERP (Event Related Potential which is widely used in BCI problems; it helps in translating the intention of subject w h i l e performing any cognitive task. EEG data contains noise due to waves generated by other activities in the brain which contaminates true P300Speller. Use of Machine Learning techniques could help in detecting errors made by P300 Speller. We are solving this classification problem by partitioning data into different chunks and preparing distributed models using Elastic CV Classifier. To present a case of optimizing distributed machine learning, we propose an intelligent user defined data partitioning approach that could impact on the accuracy of distributed machine learners on average. Our results show better average AUC as compared to average AUC obtained after applying random data partitioning which gives no control to user over data partitioning. It improves the average accuracy of distributed learner due to the domain specific intelligent partitioning by the user. Our customized approach achieves 0.66 AUC on individual sessions and 0.75 AUC on mixed sessions, whereas random / uncontrolled data distribution records 0.63 AUC.

  20. Real-Time Measurements of Gas/Particle Partitioning of Semivolatile Organic Compounds into Different Probe Particles in a Teflon Chamber

    Science.gov (United States)

    Liu, X.; Day, D. A.; Ziemann, P. J.; Krechmer, J. E.; Jimenez, J. L.

    2017-12-01

    The partitioning of semivolatile organic compounds (SVOCs) into and out of particles plays an essential role in secondary organic aerosol (SOA) formation and evolution. Most atmospheric models treat the gas/particle partitioning as an equilibrium between bulk gas and particle phases, despite potential kinetic limitations and differences in thermodynamics as a function of SOA and pre-existing OA composition. This study directly measures the partitioning of oxidized compounds in a Teflon chamber in the presence of single component seeds of different phases and polarities, including oleic acid, squalane, dioctyl sebacate, pentaethylene glycol, dry/wet ammonium sulfate, and dry/wet sucrose. The oxidized compounds are generated by a fast OH oxidation of a series of alkanols under high nitric oxide conditions. The observed SOA mass enhancements are highest with oleic acid, and lowest with wet ammonium sulfate and sucrose. A chemical ionization mass spectrometer (CIMS) was used to measure the decay of gas-phase organic nitrates, which reflects uptake by particles and chamber walls. We observed clear changes in equilibrium timescales with varying seed concentrations and in equilibrium gas-phase concentrations across different seeds. In general, the gas evolution can be reproduced by a kinetic box model that considers partitioning and evaporation with particles and chamber walls, except for the wet sucrose system. The accommodation coefficient and saturation mass concentration of each species in the presence of each seed are derived using the model. The changes in particle size distributions and composition monitored by a scanning mobility particle sizer (SMPS) and a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) are investigated to probe the SOA formation mechanism. Based on these results, the applicability of partitioning theory to these systems and the relevant quantitative parameters, including the dependencies on seed particle composition, will

  1. Parallel file system with metadata distributed across partitioned key-value store c

    Science.gov (United States)

    Bent, John M.; Faibish, Sorin; Grider, Gary; Torres, Aaron

    2017-09-19

    Improved techniques are provided for storing metadata associated with a plurality of sub-files associated with a single shared file in a parallel file system. The shared file is generated by a plurality of applications executing on a plurality of compute nodes. A compute node implements a Parallel Log Structured File System (PLFS) library to store at least one portion of the shared file generated by an application executing on the compute node and metadata for the at least one portion of the shared file on one or more object storage servers. The compute node is also configured to implement a partitioned data store for storing a partition of the metadata for the shared file, wherein the partitioned data store communicates with partitioned data stores on other compute nodes using a message passing interface. The partitioned data store can be implemented, for example, using Multidimensional Data Hashing Indexing Middleware (MDHIM).

  2. Integer Programming Formulation of the Problem of Generating Milton Babbitt's All-partition Arrays

    DEFF Research Database (Denmark)

    Tanaka, Tsubasa; Bemman, Brian; Meredith, David

    2016-01-01

    Milton Babbitt (1916–2011) was a composer of twelve-tone serial music noted for creating the all-partition array. The problem of generating an all-partition array involves finding a rectangular array of pitch-class integers that can be partitioned into regions, each of which represents a distinct...

  3. Accelerating SPARQL queries by exploiting hash-based locality and adaptive partitioning

    KAUST Repository

    Al-Harbi, Razen; Abdelaziz, Ibrahim; Kalnis, Panos; Mamoulis, Nikos; Ebrahim, Yasser; Sahli, Majed

    2016-01-01

    State-of-the-art distributed RDF systems partition data across multiple computer nodes (workers). Some systems perform cheap hash partitioning, which may result in expensive query evaluation. Others try to minimize inter-node communication, which

  4. Resource partitioning among top predators in a Miocene food web.

    Science.gov (United States)

    Domingo, M Soledad; Domingo, Laura; Badgley, Catherine; Sanisidro, Oscar; Morales, Jorge

    2013-01-07

    The exceptional fossil sites of Cerro de los Batallones (Madrid Basin, Spain) contain abundant remains of Late Miocene mammals. From these fossil assemblages, we have inferred diet, resource partitioning and habitat of three sympatric carnivorous mammals based on stable isotopes. The carnivorans include three apex predators: two sabre-toothed cats (Felidae) and a bear dog (Amphicyonidae). Herbivore and carnivore carbon isotope (δ(13)C) values from tooth enamel imply the presence of a woodland ecosystem dominated by C(3) plants. δ(13)C values and mixing-model analyses suggest that the two sabre-toothed cats, one the size of a leopard and the other the size of a tiger, consumed herbivores with similar δ(13)C values from a more wooded portion of the ecosystem. The two sabre-toothed cats probably hunted prey of different body sizes, and the smaller species could have used tree cover to avoid encounters with the larger felid. For the bear dog, δ(13)C values are higher and differ significantly from those of the sabre-toothed cats, suggesting a diet that includes prey from more open woodland. Coexistence of the sabre-toothed cats and the bear dog was likely facilitated by prey capture in different portions of the habitat. This study demonstrates the utility of stable isotope analysis for investigating the behaviour and ecology of members of past carnivoran guilds.

  5. The influence of negative training set size on machine learning-based virtual screening.

    Science.gov (United States)

    Kurczab, Rafał; Smusz, Sabina; Bojarski, Andrzej J

    2014-01-01

    The paper presents a thorough analysis of the influence of the number of negative training examples on the performance of machine learning methods. The impact of this rather neglected aspect of machine learning methods application was examined for sets containing a fixed number of positive and a varying number of negative examples randomly selected from the ZINC database. An increase in the ratio of positive to negative training instances was found to greatly influence most of the investigated evaluating parameters of ML methods in simulated virtual screening experiments. In a majority of cases, substantial increases in precision and MCC were observed in conjunction with some decreases in hit recall. The analysis of dynamics of those variations let us recommend an optimal composition of training data. The study was performed on several protein targets, 5 machine learning algorithms (SMO, Naïve Bayes, Ibk, J48 and Random Forest) and 2 types of molecular fingerprints (MACCS and CDK FP). The most effective classification was provided by the combination of CDK FP with SMO or Random Forest algorithms. The Naïve Bayes models appeared to be hardly sensitive to changes in the number of negative instances in the training set. In conclusion, the ratio of positive to negative training instances should be taken into account during the preparation of machine learning experiments, as it might significantly influence the performance of particular classifier. What is more, the optimization of negative training set size can be applied as a boosting-like approach in machine learning-based virtual screening.

  6. Partitioning and Transmutation: IAEA Activities

    International Nuclear Information System (INIS)

    Basak, U.; Monti, S.; )

    2015-01-01

    Full text of publication follows: The importance of partitioning and transmutation (P and T) processes for sustaining nuclear energy growth in the world has been realised in several countries across the world. P and T processes aim at separation and recycling of actinides including minor actinides (MAs) from the spent fuel or high-level liquid waste. The objective of these processes include reuse of separated fissile materials from spent nuclear fuels to obtain energy, enhance resource utilisation, reduce the disposal of toxic radio-nuclides and improve long-term performance of geological repositories. R and D programmes have been launched in many of the Member States to develop advanced partitioning process based on either aqueous or pyro to recover MAs along with other actinides as well as automated and remote techniques for manufacturing fuels containing MAs for the purpose of transmuting them either in fast reactors or accelerator driven hybrids. A number of Member States have been also developing such transmutation systems with the aim to construct and operate demo plants and prototypes in the next decade. The International Atomic Energy Agency has a high priority for the activities on partitioning and transmutation and regularly organises conferences, workshops, seminars and technical meetings in the areas of P and T as a part of information exchange and knowledge sharing at the international level. In the recent past, the Agency organised two technical meetings on advanced partitioning processes and actinide recycle technologies with the objective of providing a common platform for the scientists and engineers working in the areas of separation of actinides along with MAs from spent nuclear fuels and manufacturing of advanced fuels containing MAs in order to bridge the technological gap between them. In 2010, the Agency concluded a Coordinated Research Project (CRP) related to Assessment of Partitioning Processes. The Agency also conducted a first CRP on

  7. Partitioning and Transmutation - Physics, Technology and Politics

    International Nuclear Information System (INIS)

    Gudowski, W.

    2002-01-01

    Nuclear reactions can be effectively used to destroy radio toxic isotopes through transmutation processes transforming those isotopes into less radio toxic or stable ones Spent nuclear fuel, a mixture of many isotopes with some of them being highly radio toxic for many hundred thousands of years, may be effectively transmuted through nuclear reactions with neutrons. In a dedicated, well designed transmutation system one can, in principle, reduce the radiotoxicity of the spent nuclear fuel to a level, which will require isolation from the biosphere for the period of time for which engineered barriers can be constructed and licensed (not more than 1-2 thousands of years). En effective transmutation process can not be achieved without a suitable partitioning. Only partitioning of the spent nuclear fuel into predetermined groups of elements makes possible an effective use of neutrons to transmute long-lived radioactive isotopes into short-lived or stable one. However, most of the chemical separation/partitioning processes are element- not isotope-specific, therefore the transmutation of the elements with an existing isotope composition is a typical alternative for transmutation processes. Isotope-specific separation is possible but still very expensive and technologically not matured

  8. Constraining Aggregate-Scale Solar Energy Partitioning in Arctic Sea Ice Through Synthesis of Remote Sensing and Autonomous In-Situ Observations.

    Science.gov (United States)

    Wright, N.; Polashenski, C. M.; Deeb, E. J.; Morriss, B. F.; Song, A.; Chen, J.

    2015-12-01

    One of the key processes controlling sea ice mass balance in the Arctic is the partitioning of solar energy between reflection back to the atmosphere and absorption into the ice and upper ocean. We investigate the solar energy balance in the ice-ocean system using in-situ data collected from Arctic Observing Network (AON) sea ice sites and imagery from high resolution optical satellites. AON assets, including ice mass balance buoys and ice tethered profilers, monitor the storage and fluxes of heat in the ice-ocean system. High resolution satellite imagery, processed using object-based image classification techniques, allows us to quantify the evolution of surrounding ice conditions, including melt pond coverage and floe size distribution, at aggregate scale. We present results from regionally representative sites that constrain the partitioning of absorbed solar energy between ice melt and ocean storage, and quantify the strength of the ice-albedo feedback. We further demonstrate how the results can be used to validate model representations of the physical processes controlling ice-albedo feedbacks. The techniques can be extended to understand solar partitioning across the Arctic basin using additional sites and model based data integration.

  9. Determining the Variability of Lesion Size Measurements from CT Patient Data Sets Acquired under “No Change” Conditions

    Directory of Open Access Journals (Sweden)

    Michael F. McNitt-Gray

    2015-02-01

    Full Text Available PURPOSE: To determine the variability of lesion size measurements in computed tomography data sets of patients imaged under a “no change” (“coffee break” condition and to determine the impact of two reading paradigms on measurement variability. METHOD AND MATERIALS: Using data sets from 32 non-small cell lung cancer patients scanned twice within 15 minutes (“no change”, measurements were performed by five radiologists in two phases: (1 independent reading of each computed tomography dataset (timepoint: (2 a locked, sequential reading of datasets. Readers performed measurements using several sizing methods, including one-dimensional (1D longest in-slice dimension and 3D semi-automated segmented volume. Change in size was estimated by comparing measurements performed on both timepoints for the same lesion, for each reader and each measurement method. For each reading paradigm, results were pooled across lesions, across readers, and across both readers and lesions, for each measurement method. RESULTS: The mean percent difference (±SD when pooled across both readers and lesions for 1D and 3D measurements extracted from contours was 2.8 ± 22.2% and 23.4 ± 105.0%, respectively, for the independent reads. For the locked, sequential reads, the mean percent differences (±SD reduced to 2.52 ± 14.2% and 7.4 ± 44.2% for the 1D and 3D measurements, respectively. CONCLUSION: Even under a “no change” condition between scans, there is variation in lesion size measurements due to repeat scans and variations in reader, lesion, and measurement method. This variation is reduced when using a locked, sequential reading paradigm compared to an independent reading paradigm.

  10. Task Mapping and Partition Allocation for Mixed-Criticality Real-Time Systems

    DEFF Research Database (Denmark)

    Tamas-Selicean, Domitian; Pop, Paul

    2012-01-01

    In this paper we address the mapping of mixedcriticality hard real-time applications on distributed embedded architectures. We assume that the architecture provides both spatial and temporal partitioning, thus enforcing enough separation between applications. With temporal partitioning, each...

  11. Partition-based discrete-time quantum walks

    Science.gov (United States)

    Konno, Norio; Portugal, Renato; Sato, Iwao; Segawa, Etsuo

    2018-04-01

    We introduce a family of discrete-time quantum walks, called two-partition model, based on two equivalence-class partitions of the computational basis, which establish the notion of local dynamics. This family encompasses most versions of unitary discrete-time quantum walks driven by two local operators studied in literature, such as the coined model, Szegedy's model, and the 2-tessellable staggered model. We also analyze the connection of those models with the two-step coined model, which is driven by the square of the evolution operator of the standard discrete-time coined walk. We prove formally that the two-step coined model, an extension of Szegedy model for multigraphs, and the two-tessellable staggered model are unitarily equivalent. Then, selecting one specific model among those families is a matter of taste not generality.

  12. Effects of display set size and its variability on the event-related potentials during a visual search task

    OpenAIRE

    Miyatani, Makoto; Sakata, Sumiko

    1999-01-01

    This study investigated the effects of display set size and its variability on the event-related potentials (ERPs) during a visual search task. In Experiment 1, subjects were required to respond if a visual display, which consisted of two, four, or six alphabets, contained one of two members of memory set. In Experiment 2, subjects detected the change of the shape of a fixation stimulus, which was surrounded by the same alphabets as in Experiment 1. In the search task (Experiment 1), the incr...

  13. The Optimization of In-Memory Space Partitioning Trees for Cache Utilization

    Science.gov (United States)

    Yeo, Myung Ho; Min, Young Soo; Bok, Kyoung Soo; Yoo, Jae Soo

    In this paper, a novel cache conscious indexing technique based on space partitioning trees is proposed. Many researchers investigated efficient cache conscious indexing techniques which improve retrieval performance of in-memory database management system recently. However, most studies considered data partitioning and targeted fast information retrieval. Existing data partitioning-based index structures significantly degrade performance due to the redundant accesses of overlapped spaces. Specially, R-tree-based index structures suffer from the propagation of MBR (Minimum Bounding Rectangle) information by updating data frequently. In this paper, we propose an in-memory space partitioning index structure for optimal cache utilization. The proposed index structure is compared with the existing index structures in terms of update performance, insertion performance and cache-utilization rate in a variety of environments. The results demonstrate that the proposed index structure offers better performance than existing index structures.

  14. Evaluation of the performance and limitations of empirical partition-relations and process based multisurface models to predict trace element solubility in soils

    Energy Technology Data Exchange (ETDEWEB)

    Groenenberg, J.E.; Bonten, L.T.C. [Alterra, Wageningen UR, P.O. Box 47, 6700 AA Wageningen (Netherlands); Dijkstra, J.J. [Energy research Centre of the Netherlands ECN, P.O. Box 1, 1755 ZG Petten (Netherlands); De Vries, W. [Department of Environmental Systems Analysis, Wageningen University, Wageningen UR, P.O. Box 47, 6700 AA Wageningen (Netherlands); Comans, R.N.J. [Department of Soil Quality, Wageningen University, Wageningen UR, P.O. Box 47, 6700 AA Wageningen (Netherlands)

    2012-07-15

    Here we evaluate the performance and limitations of two frequently used model-types to predict trace element solubility in soils: regression based 'partition-relations' and thermodynamically based 'multisurface models', for a large set of elements. For this purpose partition-relations were derived for As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, Se, V, Zn. The multi-surface model included aqueous speciation, mineral equilibria, sorption to organic matter, Fe/Al-(hydr)oxides and clay. Both approaches were evaluated by their application to independent data for a wide variety of conditions. We conclude that Freundlich-based partition-relations are robust predictors for most cations and can be used for independent soils, but within the environmental conditions of the data used for their derivation. The multisurface model is shown to be able to successfully predict solution concentrations over a wide range of conditions. Predicted trends for oxy-anions agree well for both approaches but with larger (random) deviations than for cations.

  15. Actinide and fission product partitioning and transmutation. Status and assessment report

    International Nuclear Information System (INIS)

    1999-01-01

    Implementation and partitioning technology is intended to reduce the inventory of actinides and long-lived fission products in nuclear waste. Such technology can decrease hazards of pre-disposal waste management and of physical disturbance of a waste repository. An authoritative analysis is given of the technical, radiological and economic consequences of the proposed partitioning and transmutation operations on the present and future fuel cycle options. The report is subdivided to a general part for non-specialist readers, and to a technical systems analysis discussing issues on partitioning, transmutation and long-term waste management. (R.P.)

  16. Linking nitrogen partitioning and species abundance to invasion resistance in the Great Basin

    Science.gov (United States)

    J. J. James; K. W. Davies; R. L. Sheley; Z. T. Aanderud

    2008-01-01

    Resource partitioning has been suggested as an important mechanism of invasion resistance. The relative importance of resource partitioning for invasion resistance, however, may depend on how species abundance is distributed in the plant community. This study had two objectives. First, we quantified the degree to which one resource, nitrogen (N), is partitioned by time...

  17. Indoor Place Categorization based on Adaptive Partitioning of Texture Histograms

    Directory of Open Access Journals (Sweden)

    Sven Eberhardt

    2014-12-01

    Full Text Available How can we localize ourselves within a building solely using visual information, i.e., when no data about prior location or movement are available? Here, we define place categorization as a set of three distinct image classification tasks for view matching, location matching, and room matching. We present a novel image descriptor built on texture statistics and dynamic image partitioning that can be used to solve all tested place classification tasks. We benchmark the descriptor by assessing performance of regularization on our own dataset as well as the established Indoor Environment under Changing conditionS dataset, which varies lighting condition, location, and viewing angle on photos taken within an office building. We show improvement on both the datasets against a number of baseline algorithms.

  18. Metals partitioning resulting from rotary kiln incineration of hazardous waste

    International Nuclear Information System (INIS)

    Richards, M.K.; Fournier, D.J. Jr.

    1992-01-01

    In response to the need for date on the partitioning of trace metals from hazardous waste incinerators, an extensive series of test was conducted in the summer of 1991 at the USEPA Incineration Research Facility (IRF) in Jefferson, Arkansas. These tests were conducted in the IRF's rotary kiln incinerator system (RKS) equipped with a pilot-scale Calvert Flux-Force/Condensation scrubber as the primary air pollution control system (APCS). The purpose of this test series was to extend the data base on trace metal partitioning and to investigate the effects of variations in incinerator operation on metal partitioning. Another objective was to evaluate the effectiveness of the scrubber for collecting flue gas metals. This series is a continuation of an ongoing IRF research program investigating trace metal partitioning and APCS collection efficiencies. Two previous test series were conducted using the RKS equipped with a venturi/packed-column scrubber and a single-state ionizing wet scrubber. The primary objective of this test series was to determine the fate of six hazardous and four nonhazardous trace metals fed to the RKS in a synthetic, organic-contaminated solid waste matrix. The six hazardous trace metals used were arsenic, barium, cadmium, chromium, mercury, and lead. The four nonhazardous trace metals--bismuth, copper, magnesium, and strontium--were included primarily to supply data to evaluate their potential for use as surrogates. The temperature, waste feed chlorine content, and scrubber pressure drop. The test program objectives were to identify. The partitioning of metals among kiln ash, scrubber liquor, and flue gas. Changes in metal partitioning related to variations in kiln exit gas temperature and waste feed chlorine content. The efficiency of the Calvert scrubber for collecting flue gas metals. The effects of scrubber pressure drop on metal collection efficiencies. 2 figs., 2 tabs

  19. Strong ion exchange in centrifugal partition extraction (SIX-CPE): effect of partition cell design and dimensions on purification process efficiency.

    Science.gov (United States)

    Hamzaoui, Mahmoud; Hubert, Jane; Reynaud, Romain; Marchal, Luc; Foucault, Alain; Renault, Jean-Hugues

    2012-07-20

    The aim of this article was to evaluate the influence of the column design of a hydrostatic support-free liquid-liquid chromatography device on the process efficiency when the strong ion-exchange (SIX) development mode is used. The purification of p-hydroxybenzylglucosinolate (sinalbin) from a crude aqueous extract of white mustard seeds (Sinapis alba L.) was achieved on two types of devices: a centrifugal partition chromatograph (CPC) and a centrifugal partition extractor (CPE). They differ in the number, volume and geometry of their partition cells. The SIX-CPE process was evaluated in terms of productivity and sinalbin purification capability as compared to previously optimized SIX-CPC protocols that were carried out on columns of 200 mL and 5700 mL inner volume, respectively. The objective was to determine whether the decrease in partition cell number, the increase in their volume and the use of a "twin cell" design would induce a significant increase in productivity by applying higher mobile phase flow rate while maintaining a constant separation quality. 4.6g of sinalbin (92% recovery) were isolated from 25 g of a crude white mustard seed extract, in only 32 min and with a purity of 94.7%, thus corresponding to a productivity of 28 g per hour and per liter of column volume (g/h/LV(c)). Therefore, the SIX-CPE process demonstrates promising industrial technology transfer perspectives for the large-scale isolation of ionized natural products. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Influence of biochar on isoproturon partitioning and bioaccessibility in soil.

    Science.gov (United States)

    Reid, B J; Pickering, F L; Freddo, A; Whelan, M J; Coulon, F

    2013-10-01

    The influence of biochar (5%) on the loss, partitioning and bioaccessibility of (14)C-isoproturon ((14)C-IPU) was evaluated. Results indicated that biochar had a dramatic effect upon (14)C-IPU partitioning: (14)C-IPU extractability (0.01 M CaCl2) in biochar-amended treatments was reduced to <2% while, (14)C-IPU extractability in biochar free treatments decreased with ageing from 90% to 40%. A partitioning model was constructed to derive an effective partition coefficient for biochar:water (KBW of 7.82 × 10(4) L kg(-1)). This was two orders of magnitude greater than the apparent Kfoc value of the soil organic carbon:water (631 L kg(-1)). (14)C-radiorespirometry assays indicated high competence of microorganisms to mineralise (14)C-IPU in the absence of biochar (40.3 ± 0.9%). Where biochar was present (14)C-IPU mineralisation never exceeded 2%. These results indicate reduced herbicide bioaccessibility. Increasing IPU application to ×10 its recommended dose was ineffective at redressing IPU sequestration and its low bioaccessibility. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. The calculation of isotopic partition function ratios by a perturbation theory technique

    International Nuclear Information System (INIS)

    Singh, G.; Wolfsberg, M.

    1975-01-01

    The vibrational Hamiltonian of a molecule in the harmonic approximation, H = (1/2) Σ (g/subi/jp/subi/p/subj/ + f/subi/jq/subi/q/subj/), has been divided into a diagonal part (terms with i=j) and an off-diagonal part (inot-equalj), which is regarded as the perturbation. The vibrational partition function of the molecule is then calculated by Schwinger perturbation theory as the partition function of the unperturbed problem, corresponding to a collection of oscillators with frequencies 2πν/subi/' = (f/subi/ig/subi/i)/sup 1 / 2 /, plus perturbation correction terms which are calculated to second order. With the usual assumptions of isotope effect calculations that the molecular translations and rotations are classical and separable from the vibrations, the perturbation formulation of the vibrational partition function is easily transformed into a perturbation theory formulation of (reduced) isotopic partition function ratios. If, for example, the molecular potential function is expressed in terms of the displacements of bond stretches and bond angle bends from their respective equilibrium values, the unperturbed partition function ratio corresponds to the isotope effect expected for noninteracting bond-stretch and bond-angle-bend oscillators. Detailed comparison is made for a number of molecular systems of perturbation theory calculations of partition functions and isotopic partition function ratios with exact calculations carried out by actually obtaining the normal mode vibrational frequencies of the vibrational Hamiltonian. Good agreement is found. The utility of the perturbation theory formulation resides in the fact that it permits one to look at isotope effects in a very simple manner; some demonstrations are given

  2. The Influence of Oxygen and Sulfur on Uranium Partitioning Into the Core

    Science.gov (United States)

    Moore, R. D., Jr.; Van Orman, J. A.; Hauck, S. A., II

    2017-12-01

    Uranium, along with K and Th, may provide substantial long-term heating in planetary cores, depending on the magnitude of their partitioning into the metal during differentiation. In general, non-metallic light elements are known to have a large influence on the partitioning of trace elements, and the presence of sulfur is known to enhance the partitioning of uranium into the metal. Data from the steelmaking literature indicate that oxygen also enhances the solubility of oxygen in liquid iron alloys. Here we present experimental data on the partitioning of U between immiscible liquids in the Fe-S-O system, and use these data along with published metal-silicate partitioning data to calibrate a quantitative activity model for U in the metal. We also determined partition coefficients for Th, K, Nb, Nd, Sm, and Yb, but were unable to fully constrain activity models for these elements with available data. A Monte Carlo fitting routine was used to calculate U-S, U-O, and U-S-O interaction coefficients, and their associated uncertainties. We find that the combined interaction of uranium with sulfur and oxygen is predominant, with S and O together enhancing the solubility of uranium to a far greater degree than either element in isolation. This suggests that uranium complexes with sulfite or sulfate species in the metal. For a model Mars core composition containing 14 at% S and 5 at% O, the metal/silicate partition coefficient for U is predicted to be an order of magnitude larger than for a pure Fe-Ni core.

  3. The French partitioning-transmutation programme, assets and prospects

    International Nuclear Information System (INIS)

    Viala, M.; Salvatores, M.; Mouney, H.

    1997-01-01

    Partitioning-transmutation studies are covered by the 1991 French law concerning radioactive waste management. The programme is progressing with a dual approach: - What can be done in partitioning-transmutation? At what cost? In what timescale? - How can long-term gains and short-term disadvantages be qualified and quantified? The first approach concerns technical know-how. The studies based on today's technologies are continuing (reactors, fuels and targets, separation of radionuclides by solvents). The second approach involves an assessment activity, based firstly on studies of scenarios. Pertinent assessment criteria must be brought out. (authors)

  4. Marginal Consistency: Upper-Bounding Partition Functions over Commutative Semirings.

    Science.gov (United States)

    Werner, Tomás

    2015-07-01

    Many inference tasks in pattern recognition and artificial intelligence lead to partition functions in which addition and multiplication are abstract binary operations forming a commutative semiring. By generalizing max-sum diffusion (one of convergent message passing algorithms for approximate MAP inference in graphical models), we propose an iterative algorithm to upper bound such partition functions over commutative semirings. The iteration of the algorithm is remarkably simple: change any two factors of the partition function such that their product remains the same and their overlapping marginals become equal. In many commutative semirings, repeating this iteration for different pairs of factors converges to a fixed point when the overlapping marginals of every pair of factors coincide. We call this state marginal consistency. During that, an upper bound on the partition function monotonically decreases. This abstract algorithm unifies several existing algorithms, including max-sum diffusion and basic constraint propagation (or local consistency) algorithms in constraint programming. We further construct a hierarchy of marginal consistencies of increasingly higher levels and show than any such level can be enforced by adding identity factors of higher arity (order). Finally, we discuss instances of the framework for several semirings, including the distributive lattice and the max-sum and sum-product semirings.

  5. Transfer functions for solid solution partitioning of cadmium for Australian soils

    NARCIS (Netherlands)

    Vries, de W.; Mc Laughlin, M.J.; Groenenberg, J.E.

    2011-01-01

    To assess transport and ecotoxicological risks of metals, such as cadmium (Cd) in soils, models are needed for partitioning and speciation. We derived regression-based “partition-relations” based on adsorption and desorption experiments for main Australian soil types. First, batch adsorption

  6. Many-body formalism for fermions: The partition function

    Science.gov (United States)

    Watson, D. K.

    2017-09-01

    The partition function, a fundamental tenet in statistical thermodynamics, contains in principle all thermodynamic information about a system. It encapsulates both microscopic information through the quantum energy levels and statistical information from the partitioning of the particles among the available energy levels. For identical particles, this statistical accounting is complicated by the symmetry requirements of the allowed quantum states. In particular, for Fermi systems, the enforcement of the Pauli principle is typically a numerically demanding task, responsible for much of the cost of the calculations. The interplay of these three elements—the structure of the many-body spectrum, the statistical partitioning of the N particles among the available levels, and the enforcement of the Pauli principle—drives the behavior of mesoscopic and macroscopic Fermi systems. In this paper, we develop an approach for the determination of the partition function, a numerically difficult task, for systems of strongly interacting identical fermions and apply it to a model system of harmonically confined, harmonically interacting fermions. This approach uses a recently introduced many-body method that is an extension of the symmetry-invariant perturbation method (SPT) originally developed for bosons. It uses group theory and graphical techniques to avoid the heavy computational demands of conventional many-body methods which typically scale exponentially with the number of particles. The SPT application of the Pauli principle is trivial to implement since it is done "on paper" by imposing restrictions on the normal-mode quantum numbers at first order in the perturbation. The method is applied through first order and represents an extension of the SPT method to excited states. Our method of determining the partition function and various thermodynamic quantities is accurate and efficient and has the potential to yield interesting insight into the role played by the Pauli

  7. Modular invariant partition functions for toroidally compactified bosonic string

    International Nuclear Information System (INIS)

    Ardalan, F.; Arfaei, H.

    1988-06-01

    We systematically find all the modular invariant partition functions for the toroidally compactified closed bosonic string defined on a subset of a simply laced simple Lie algebra lattice, or equivalently for the closed bosonic string moving on a group manifold with the WZW coefficient k=1. We examine the relation between modular invariance of partition function and the possibility of describing it by an even Lorentzian self dual lattice in our context. (author). 23 refs

  8. Study and obtention of exact, and approximation, algorithms and heuristics for a mesh partitioning problem under memory constraints

    International Nuclear Information System (INIS)

    Morais, Sebastien

    2016-01-01

    In many scientific areas, the size and the complexity of numerical simulations lead to make intensive use of massively parallel runs on High Performance Computing (HPC) architectures. Such computers consist in a set of processing units (PU) where memory is distributed. Distribution of simulation data is therefore crucial: it has to minimize the computation time of the simulation while ensuring that the data allocated to every PU can be locally stored in memory. For most of the numerical simulations, the physical and numerical data are based on a mesh. The computations are then performed at the cell level (for example within triangles and quadrilaterals in 2D, or within tetrahedrons and hexahedrons in 3D). More specifically, computing and memory cost can be associated to each cell. In our context, where the mathematical methods used are finite elements or finite volumes, the realization of the computations associated with a cell may require information carried by neighboring cells. The standard implementation relies to locally store useful data of this neighborhood on the PU, even if cells of this neighborhood are not locally computed. Such non computed but stored cells are called ghost cells, and can have a significant impact on the memory consumption of a PU. The problem to solve is thus not only to partition a mesh on several parts by affecting each cell to one and only one part while minimizing the computational load assigned to each part. It is also necessary to keep into account that the memory load of both the cells where the computations are performed and their neighbors has to fit into PU memory. This leads to partition the computations while the mesh is distributed with overlaps. Explicitly taking these data overlaps into account is the problem that we propose to study. (author) [fr

  9. Hemisphere partition function and monodromy

    Energy Technology Data Exchange (ETDEWEB)

    Erkinger, David; Knapp, Johanna [Institute for Theoretical Physics, TU Wien,Wiedner Hauptstrasse 8-10, 1040 Vienna (Austria)

    2017-05-29

    We discuss D-brane monodromies from the point of view of the gauged linear sigma model. We give a prescription on how to extract monodromy matrices directly from the hemisphere partition function. We illustrate this procedure by recomputing the monodromy matrices associated to one-parameter Calabi-Yau hypersurfaces in weighted projected space.

  10. SVOC partitioning between the gas phase and settled dust indoors

    Science.gov (United States)

    Weschler, Charles J.; Nazaroff, William W.

    2010-09-01

    Semivolatile organic compounds (SVOCs) are a major class of indoor pollutants. Understanding SVOC partitioning between the gas phase and settled dust is important for characterizing the fate of these species indoors and the pathways by which humans are exposed to them. Such knowledge also helps in crafting measurement programs for epidemiological studies designed to probe potential associations between exposure to these compounds and adverse health effects. In this paper, we analyze published data from nineteen studies that cumulatively report measurements of dustborne and airborne SVOCs in more than a thousand buildings, mostly residences, in seven countries. In aggregate, measured median data are reported in these studies for 66 different SVOCs whose octanol-air partition coefficients ( Koa) span more than five orders of magnitude. We use these data to test a simple equilibrium model for estimating the partitioning of an SVOC between the gas phase and settled dust indoors. The results demonstrate, in central tendency, that a compound's octanol-air partition coefficient is a strong predictor of its abundance in settled dust relative to its gas phase concentration. Using median measured results for each SVOC in each study, dustborne mass fractions predicted using Koa and gas-phase concentrations correlate reasonably well with measured dustborne mass fractions ( R2 = 0.76). Combined with theoretical understanding of SVOC partitioning kinetics, the empirical evidence also suggests that for SVOCs with high Koa values, the mass fraction in settled dust may not have sufficient time to equilibrate with the gas phase concentration.

  11. COMPARISON OF THE OCTANOL-AIR PARTITION COEFFICIENT AND LIQUID-PHASE VAPOR PRESSURE AS DESCRIPTORS FOR PARTICLE/GAS PARTITIONING USING LABORATORY AND FIELD DATA FOR PCBS AND PCNS

    Science.gov (United States)

    The conventional Junge-Pankow adsorption model uses the sub-cooled liquid vapor pressure (pLo) as a correlation parameter for gas/particle interactions. An alternative is the octanol-air partition coefficient (Koa) absorption model. Log-log plots of the particle-gas partition c...

  12. An approach to develop chemical intuition for atomistic electron transport calculations using basis set rotations

    Energy Technology Data Exchange (ETDEWEB)

    Borges, A.; Solomon, G. C. [Department of Chemistry and Nano-Science Center, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø (Denmark)

    2016-05-21

    Single molecule conductance measurements are often interpreted through computational modeling, but the complexity of these calculations makes it difficult to directly link them to simpler concepts and models. Previous work has attempted to make this connection using maximally localized Wannier functions and symmetry adapted basis sets, but their use can be ambiguous and non-trivial. Starting from a Hamiltonian and overlap matrix written in a hydrogen-like basis set, we demonstrate a simple approach to obtain a new basis set that is chemically more intuitive and allows interpretation in terms of simple concepts and models. By diagonalizing the Hamiltonians corresponding to each atom in the molecule, we obtain a basis set that can be partitioned into pseudo-σ and −π and allows partitioning of the Landuaer-Büttiker transmission as well as create simple Hückel models that reproduce the key features of the full calculation. This method provides a link between complex calculations and simple concepts and models to provide intuition or extract parameters for more complex model systems.

  13. Rotational partition functions for linear molecules

    International Nuclear Information System (INIS)

    McDowell, R.S.

    1988-01-01

    An accurate closed-form expression for the rotational partition function of linear polyatomic molecules in 1 summation electronic states is derived, including the effect of nuclear spin (significant at very low temperatures) and of quartic and sextic centrifugal distortion terms (significant at moderate and high temperatures). The proper first-order quantum correction to the classical rigid-rotator partition function is shown to yield Q/sub r/ ≅β -1 exp(β/3), where βequivalenthcB/kT and B is the rotational constant in cm -1 ; for β≥0.2 additional power-series terms in β are necessary. Comparison between the results of this treatment and exact summations are made for HCN and C 2 H 2 at temperatures from 2 to 5000 K, including separate evaluation of the contributions of nuclear spin and centrifugal distortion

  14. Hydrology and empire: the Nile, water imperialism and the partition of Africa.

    Science.gov (United States)

    Tvedt, Terje

    2011-01-01

    Why did the British march up the Nile in the 1890s? The answers to this crucial question of imperial historiography have direct relevance for narratives and theories about imperialism, in general, and the partition of Africa in the nineteenth century, in particular. They will also influence our understanding of some of the main issues in the modern history of the whole region, including state developments and resource utilisation. This article presents an alternative to dominant interpretations of the partition of Africa and the role of British Nile policies in this context. It differs from mainstream diplomatic history, which dominates this research field, in its emphasis on how geographical factors and the hydrological characteristics of the Nile influenced and framed British thinking and actions in the region. Realising the importance of such factors and the specific character of the regional water system does not imply less attention to traditional diplomatic correspondence or to the role of individual imperial entrepreneurs. The strength of this analytical approach theoretically is that it makes it possible to locate the intentions and acts of historical subjects within specific geographical contexts. Empirically, it opens up a whole new set of source material, embedding the reconstruction of the British Nile discourse in a world of Nile plans, water works and hydrological discourses.

  15. A homeostatic clock sets daughter centriole size in flies

    Science.gov (United States)

    Aydogan, Mustafa G.; Steinacker, Thomas L.; Novak, Zsofia A.; Baumbach, Janina; Muschalik, Nadine

    2018-01-01

    Centrioles are highly structured organelles whose size is remarkably consistent within any given cell type. New centrioles are born when Polo-like kinase 4 (Plk4) recruits Ana2/STIL and Sas-6 to the side of an existing “mother” centriole. These two proteins then assemble into a cartwheel, which grows outwards to form the structural core of a new daughter. Here, we show that in early Drosophila melanogaster embryos, daughter centrioles grow at a linear rate during early S-phase and abruptly stop growing when they reach their correct size in mid- to late S-phase. Unexpectedly, the cartwheel grows from its proximal end, and Plk4 determines both the rate and period of centriole growth: the more active the centriolar Plk4, the faster centrioles grow, but the faster centriolar Plk4 is inactivated and growth ceases. Thus, Plk4 functions as a homeostatic clock, establishing an inverse relationship between growth rate and period to ensure that daughter centrioles grow to the correct size. PMID:29500190

  16. Equilibrium Partitioning Sediment Benchmarks (ESBs) for the ...

    Science.gov (United States)

    This document describes procedures to determine the concentrations of nonionic organic chemicals in sediment interstitial waters. In previous ESB documents, the general equilibrium partitioning (EqP) approach was chosen for the derivation of sediment benchmarks because it accounts for the varying bioavailability of chemicals in different sediments and allows for the incorporation of the appropriate biological effects concentration. This provides for the derivation of benchmarks that are causally linked to the specific chemical, applicable across sediments, and appropriately protective of benthic organisms.  This equilibrium partitioning sediment benchmark (ESB) document was prepared by scientists from the Atlantic Ecology Division, Mid-Continent Ecology Division, and Western Ecology Division, the Office of Water, and private consultants. The document describes procedures to determine the interstitial water concentrations of nonionic organic chemicals in contaminated sediments. Based on these concentrations, guidance is provided on the derivation of toxic units to assess whether the sediments are likely to cause adverse effects to benthic organisms. The equilibrium partitioning (EqP) approach was chosen because it is based on the concentrations of chemical(s) that are known to be harmful and bioavailable in the environment.  This document, and five others published over the last nine years, will be useful for the Program Offices, including Superfund, a

  17. Effects of shading on dry matter partitioning and yield of field-grown sunflower

    International Nuclear Information System (INIS)

    Villalobos, F.J.; Soriano, A.; Fereres, E.

    1992-01-01

    Crop simulation models require quantitative descriptions of the effects of irradiance on dry matter partition and yield. The objective of this work was to quantify the effects of reduced radiation intensity during different phenological stages on the growth, dry matter partitioning and grain numbers of sunflower (Helianthus annuus, L.). A field experiment was carried out in 1990 with 50 per cent shading treatments. The earliest treatment began at crop emergence while the latest ended at first anthesis. Shading had little effect on plant leaf area growth but reduced biomass and yield. The dry matter: radiation quotient and specific leaf area increased with shading. Grain number per head was decreased by shading, with the greatest effect occurring when shading was applied prior to anthesis. All shading treatments increased dry matter partitioning to stems, decreased assimilate partitioning to the heads and had no effect on the partitioning to leaves. (author)

  18. Gentile statistics and restricted partitions

    Indian Academy of Sciences (India)

    In a recent paper (Tran et al, Ann. Phys. 311, 204 (2004)), some asymptotic number theoretical results on the partitioning of an integer were derived exploiting its connection to the quantum density of states of a many-particle system. We generalise these results to obtain an asymptotic formula for the restricted or coloured ...

  19. Dissipative particle dynamics: Systematic parametrization using water-octanol partition coefficients

    Science.gov (United States)

    Anderson, Richard L.; Bray, David J.; Ferrante, Andrea S.; Noro, Massimo G.; Stott, Ian P.; Warren, Patrick B.

    2017-09-01

    We present a systematic, top-down, thermodynamic parametrization scheme for dissipative particle dynamics (DPD) using water-octanol partition coefficients, supplemented by water-octanol phase equilibria and pure liquid phase density data. We demonstrate the feasibility of computing the required partition coefficients in DPD using brute-force simulation, within an adaptive semi-automatic staged optimization scheme. We test the methodology by fitting to experimental partition coefficient data for twenty one small molecules in five classes comprising alcohols and poly-alcohols, amines, ethers and simple aromatics, and alkanes (i.e., hexane). Finally, we illustrate the transferability of a subset of the determined parameters by calculating the critical micelle concentrations and mean aggregation numbers of selected alkyl ethoxylate surfactants, in good agreement with reported experimental values.

  20. Assimilate partitioning in avocado, Persea americana

    Energy Technology Data Exchange (ETDEWEB)

    Finazzo, S.; Davenport, T.L.

    1986-04-01

    Assimilate partitioning is being studied in avocado, Persea americana cv. Millborrow in relation to fruit set. Single leaves on girdled branches of 10 year old trees were radiolabeled for 1 hr with 13..mu..Ci of /sup 14/CO/sub 2/. The source leaves were sampled during the experiment to measure translocation rates. At harvest the sink tissues were dissected and the incorporated radioactivity was measured. The translocation of /sup 14/C-labelled compounds to other leaves was minimal. Incorporation of label into fruitlets varied with the tissue and the stage of development. Sink (fruitlets) nearest to the labelled leaf and sharing the same phyllotaxy incorporated the most /sup 14/C. Source leaves for single non-abscising fruitlets retained 3X more /sup 14/C-labelled compounds than did source leaves for 2 or more fruitlets at 31 hrs. post-labelling. Export of label decreased appreciably when fruitlets abscised. If fruitlets abscised within 4 days of labeling then the translocation pattern was similar to the pattern for single fruitlets. If the fruitlet abscised later, the translocation pattern was intermediate between the single and double fruitlet pattern.

  1. Origin of Asymmetric Charge Partitioning in the Dissociation of Gas-Phase Protein Homodimers

    OpenAIRE

    Jurchen, John C.; Williams, Evan R.

    2003-01-01

    The origin of asymmetric charge and mass partitioning observed for gas-phase dissociation of multiply charged macromolecular complexes has been hotly debated. These experiments hold the potential to provide detailed information about the interactions between the macromolecules within the complex. Here, this unusual phenomenon of asymmetric charge partitioning is investigated for several protein homodimers. Asymmetric charge partitioning in these ions depends on a number of factors, including ...

  2. Local recurrence after surgery for non-small cell lung cancer: a recursive partitioning analysis of multi-institutional data.

    Science.gov (United States)

    Kelsey, Chris R; Higgins, Kristin A; Peterson, Bercedis L; Chino, Junzo P; Marks, Lawrence B; D'Amico, Thomas A; Varlotto, John M

    2013-10-01

    To define subgroups at high risk of local recurrence (LR) after surgery for non-small cell lung cancer using a recursive partitioning analysis (RPA). This Institutional Review Board-approved study included patients who underwent upfront surgery for I-IIIA non-small cell lung cancer at Duke Cancer Institute (primary set) or at other participating institutions (validation set). The 2 data sets were analyzed separately and identically. Disease recurrence at the surgical margin, ipsilateral hilum, and/or mediastinum was considered an LR. Recursive partitioning was used to build regression trees for the prediction of local recurrence-free survival (LRFS) from standard clinical and pathological factors. LRFS distributions were estimated with the Kaplan-Meier method. The 1411 patients in the primary set had a 5-year LRFS rate of 77% (95% confidence interval [CI], 0.74-0.81), and the 889 patients in the validation set had a 5-year LRFS rate of 76% (95% CI, 0.72-0.80). The RPA of the primary data set identified 3 terminal nodes based on stage and histology. These nodes and their 5-year LRFS rates were as follows: (1) stage I/adenocarcinoma, 87% (95% CI, 0.83-0.90); (2) stage I/squamous or large cell, 72% (95% CI, 0.65-0.79); and (3) stage II-IIIA, 62% (95% CI, 0.55-0.69). The validation RPA identified 3 terminal nodes based on lymphovascular invasion (LVI) and stage: (1) no LVI/stage IA, 82% (95% CI, 0.76-0.88); (2) no LVI/stage IB-IIIA, 73% (95% CI, 0.69-0.80); and (3) LVI, 58% (95% CI, 0.47-0.69). The risk of LR was similar in the primary and validation patient data sets. There was discordance between the 2 data sets regarding the clinical factors that best segregate patients into risk groups. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  3. Partition of some key regulating services in terrestrial ecosystems: Meta-analysis and review

    Energy Technology Data Exchange (ETDEWEB)

    Viglizzo, E.F., E-mail: evigliz@cpenet.com.ar [INTA, EEA Anguil, Grupo de Investigaciones en Gestión Ambiental (GIGA), Av. Spinetto 785, 6300 Santa Rosa, La Pampa (Argentina); INCITAP-CONICET, Ruta 35, km 335, 6300 Santa Rosa, La Pampa (Argentina); UNLPam, Facultad de Ciencias Exactas y Naturales, Av. Uruguay 151, 6300 Santa Rosa, La Pampa (Argentina); Jobbágy, E.G. [CONICET, Andes 950, 5700 San Luis, San Luis (Argentina); Grupo de Estudios Ambientales IMASL, Ejército de los, Andes 950, 5700 San Luis, San Luis (Argentina); Ricard, M.F. [INCITAP-CONICET, Ruta 35, km 335, 6300 Santa Rosa, La Pampa (Argentina); UNLPam, Facultad de Ciencias Exactas y Naturales, Av. Uruguay 151, 6300 Santa Rosa, La Pampa (Argentina); Paruelo, J.M. [Laboratorio de Análisis Regional y Teledetección, Departamento de Métodos Cuantitativos Sistemas de información, Facultad de Agronomía and IFEVA, Universidad de Buenos Aires and CONICET, Av. San Martín 4453, 1417 Buenos Aires (Argentina)

    2016-08-15

    Our knowledge about the functional foundations of ecosystem service (ES) provision is still limited and more research is needed to elucidate key functional mechanisms. Using a simplified eco-hydrological scheme, in this work we analyzed how land-use decisions modify the partition of some essential regulatory ES by altering basic relationships between biomass stocks and water flows. A comprehensive meta-analysis and review was conducted based on global, regional and local data from peer-reviewed publications. We analyzed five datasets comprising 1348 studies and 3948 records on precipitation (PPT), aboveground biomass (AGB), AGB change, evapotranspiration (ET), water yield (WY), WY change, runoff (R) and infiltration (I). The conceptual framework was focused on ES that are associated with the ecological functions (e.g., intermediate ES) of ET, WY, R and I. ES included soil protection, carbon sequestration, local climate regulation, water-flow regulation and water recharge. To address the problem of data normality, the analysis included both parametric and non-parametric regression analysis. Results demonstrate that PPT is a first-order biophysical factor that controls ES release at the broader scales. At decreasing scales, ES are partitioned as result of PPT interactions with other biophysical and anthropogenic factors. At intermediate scales, land-use change interacts with PPT modifying ES partition as it the case of afforestation in dry regions, where ET and climate regulation may be enhanced at the expense of R and water-flow regulation. At smaller scales, site-specific conditions such as topography interact with PPT and AGB displaying different ES partition formats. The probable implications of future land-use and climate change on some key ES production and partition are discussed. - Highlights: • The partition of regulatory services in ecosystems poses a major policy challenge. • We examined how partitions occur at the hydrosphere

  4. Partition of some key regulating services in terrestrial ecosystems: Meta-analysis and review

    International Nuclear Information System (INIS)

    Viglizzo, E.F.; Jobbágy, E.G.; Ricard, M.F.; Paruelo, J.M.

    2016-01-01

    Our knowledge about the functional foundations of ecosystem service (ES) provision is still limited and more research is needed to elucidate key functional mechanisms. Using a simplified eco-hydrological scheme, in this work we analyzed how land-use decisions modify the partition of some essential regulatory ES by altering basic relationships between biomass stocks and water flows. A comprehensive meta-analysis and review was conducted based on global, regional and local data from peer-reviewed publications. We analyzed five datasets comprising 1348 studies and 3948 records on precipitation (PPT), aboveground biomass (AGB), AGB change, evapotranspiration (ET), water yield (WY), WY change, runoff (R) and infiltration (I). The conceptual framework was focused on ES that are associated with the ecological functions (e.g., intermediate ES) of ET, WY, R and I. ES included soil protection, carbon sequestration, local climate regulation, water-flow regulation and water recharge. To address the problem of data normality, the analysis included both parametric and non-parametric regression analysis. Results demonstrate that PPT is a first-order biophysical factor that controls ES release at the broader scales. At decreasing scales, ES are partitioned as result of PPT interactions with other biophysical and anthropogenic factors. At intermediate scales, land-use change interacts with PPT modifying ES partition as it the case of afforestation in dry regions, where ET and climate regulation may be enhanced at the expense of R and water-flow regulation. At smaller scales, site-specific conditions such as topography interact with PPT and AGB displaying different ES partition formats. The probable implications of future land-use and climate change on some key ES production and partition are discussed. - Highlights: • The partition of regulatory services in ecosystems poses a major policy challenge. • We examined how partitions occur at the hydrosphere

  5. Probabilistic Analysis of Combinatorial Optimization Problems on Hypergraph Matchings

    Science.gov (United States)

    2012-02-01

    cliques, !.G/ < k. Let B D f1; : : : ; kg be the index set of partites in G, V D S b2B Vb , and BS denote the set of partites that have a node in S : BS D...CS D [ b2BS CS;b; where BS D B n BS , and CS;b Vb is given by CS;b D [ s2S .Vb \\N.s//; with N.s/ being the set of nodes adjacent to node s. At the...to a partite Vb in G: Zt D [ b2B Zt;b; t D 1; : : : ; k: The sets Zt;b are represented by bitsets of size jVbj. Let Zt;b;i be the i -th bit in Zt;b

  6. One-loop partition functions of 3D gravity

    International Nuclear Information System (INIS)

    Giombi, Simone; Yin Xi; Maloney, Alexander

    2008-01-01

    We consider the one-loop partition function of free quantum field theory in locally Anti-de Sitter space-times. In three dimensions, the one loop determinants for scalar, gauge and graviton excitations are computed explicitly using heat kernel techniques. We obtain precisely the result anticipated by Brown and Henneaux: the partition function includes a sum over 'boundary excitations' of AdS 3 , which are the Virasoro descendants of empty Anti-de Sitter space. This result also allows us to compute the one-loop corrections to the Euclidean action of the BTZ black hole as well its higher genus generalizations.

  7. Identifying finite-time coherent sets from limited quantities of Lagrangian data

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Matthew O. [Program in Applied and Computational Mathematics, Princeton University, New Jersey 08544 (United States); Rypina, Irina I. [Department of Physical Oceanography, Woods Hole Oceanographic Institute, Massachusetts 02543 (United States); Rowley, Clarence W. [Department of Mechanical and Aerospace Engineering, Princeton University, New Jersey 08544 (United States)

    2015-08-15

    A data-driven procedure for identifying the dominant transport barriers in a time-varying flow from limited quantities of Lagrangian data is presented. Our approach partitions state space into coherent pairs, which are sets of initial conditions chosen to minimize the number of trajectories that “leak” from one set to the other under the influence of a stochastic flow field during a pre-specified interval in time. In practice, this partition is computed by solving an optimization problem to obtain a pair of functions whose signs determine set membership. From prior experience with synthetic, “data rich” test problems, and conceptually related methods based on approximations of the Perron-Frobenius operator, we observe that the functions of interest typically appear to be smooth. We exploit this property by using the basis sets associated with spectral or “mesh-free” methods, and as a result, our approach has the potential to more accurately approximate these functions given a fixed amount of data. In practice, this could enable better approximations of the coherent pairs in problems with relatively limited quantities of Lagrangian data, which is usually the case with experimental geophysical data. We apply this method to three examples of increasing complexity: The first is the double gyre, the second is the Bickley Jet, and the third is data from numerically simulated drifters in the Sulu Sea.

  8. Identifying finite-time coherent sets from limited quantities of Lagrangian data

    International Nuclear Information System (INIS)

    Williams, Matthew O.; Rypina, Irina I.; Rowley, Clarence W.

    2015-01-01

    A data-driven procedure for identifying the dominant transport barriers in a time-varying flow from limited quantities of Lagrangian data is presented. Our approach partitions state space into coherent pairs, which are sets of initial conditions chosen to minimize the number of trajectories that “leak” from one set to the other under the influence of a stochastic flow field during a pre-specified interval in time. In practice, this partition is computed by solving an optimization problem to obtain a pair of functions whose signs determine set membership. From prior experience with synthetic, “data rich” test problems, and conceptually related methods based on approximations of the Perron-Frobenius operator, we observe that the functions of interest typically appear to be smooth. We exploit this property by using the basis sets associated with spectral or “mesh-free” methods, and as a result, our approach has the potential to more accurately approximate these functions given a fixed amount of data. In practice, this could enable better approximations of the coherent pairs in problems with relatively limited quantities of Lagrangian data, which is usually the case with experimental geophysical data. We apply this method to three examples of increasing complexity: The first is the double gyre, the second is the Bickley Jet, and the third is data from numerically simulated drifters in the Sulu Sea

  9. Identifying finite-time coherent sets from limited quantities of Lagrangian data.

    Science.gov (United States)

    Williams, Matthew O; Rypina, Irina I; Rowley, Clarence W

    2015-08-01

    A data-driven procedure for identifying the dominant transport barriers in a time-varying flow from limited quantities of Lagrangian data is presented. Our approach partitions state space into coherent pairs, which are sets of initial conditions chosen to minimize the number of trajectories that "leak" from one set to the other under the influence of a stochastic flow field during a pre-specified interval in time. In practice, this partition is computed by solving an optimization problem to obtain a pair of functions whose signs determine set membership. From prior experience with synthetic, "data rich" test problems, and conceptually related methods based on approximations of the Perron-Frobenius operator, we observe that the functions of interest typically appear to be smooth. We exploit this property by using the basis sets associated with spectral or "mesh-free" methods, and as a result, our approach has the potential to more accurately approximate these functions given a fixed amount of data. In practice, this could enable better approximations of the coherent pairs in problems with relatively limited quantities of Lagrangian data, which is usually the case with experimental geophysical data. We apply this method to three examples of increasing complexity: The first is the double gyre, the second is the Bickley Jet, and the third is data from numerically simulated drifters in the Sulu Sea.

  10. Ocean surface partitioning strategies using ocean colour remote Sensing: A review

    Science.gov (United States)

    Krug, Lilian Anne; Platt, Trevor; Sathyendranath, Shubha; Barbosa, Ana B.

    2017-06-01

    The ocean surface is organized into regions with distinct properties reflecting the complexity of interactions between environmental forcing and biological responses. The delineation of these functional units, each with unique, homogeneous properties and underlying ecosystem structure and dynamics, can be defined as ocean surface partitioning. The main purposes and applications of ocean partitioning include the evaluation of particular marine environments; generation of more accurate satellite ocean colour products; assimilation of data into biogeochemical and climate models; and establishment of ecosystem-based management practices. This paper reviews the diverse approaches implemented for ocean surface partition into functional units, using ocean colour remote sensing (OCRS) data, including their purposes, criteria, methods and scales. OCRS offers a synoptic, high spatial-temporal resolution, multi-decadal coverage of bio-optical properties, relevant to the applications and value of ocean surface partitioning. In combination with other biotic and/or abiotic data, OCRS-derived data (e.g., chlorophyll-a, optical properties) provide a broad and varied source of information that can be analysed using different delineation methods derived from subjective, expert-based to unsupervised learning approaches (e.g., cluster, fuzzy and empirical orthogonal function analyses). Partition schemes are applied at global to mesoscale spatial coverage, with static (time-invariant) or dynamic (time-varying) representations. A case study, the highly heterogeneous area off SW Iberian Peninsula (NE Atlantic), illustrates how the selection of spatial coverage and temporal representation affects the discrimination of distinct environmental drivers of phytoplankton variability. Advances in operational oceanography and in the subject area of satellite ocean colour, including development of new sensors, algorithms and products, are among the potential benefits from extended use, scope and

  11. Organic Carbon/Water and Dissolved Organic Carbon/Water Partitioning of Cyclic Volatile Methylsiloxanes: Measurements and Polyparameter Linear Free Energy Relationships.

    Science.gov (United States)

    Panagopoulos, Dimitri; Jahnke, Annika; Kierkegaard, Amelie; MacLeod, Matthew

    2015-10-20

    The sorption of cyclic volatile methyl siloxanes (cVMS) to organic matter has a strong influence on their fate in the aquatic environment. We report new measurements of the partition ratios between freshwater sediment organic carbon and water (KOC) and between Aldrich humic acid dissolved organic carbon and water (KDOC) for three cVMS, and for three polychlorinated biphenyls (PCBs) that were used as reference chemicals. Our measurements were made using a purge-and-trap method that employs benchmark chemicals to calibrate mass transfer at the air/water interface in a fugacity-based multimedia model. The measured log KOC of octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) were 5.06, 6.12, and 7.07, and log KDOC were 5.05, 6.13, and 6.79. To our knowledge, our measurements for KOC of D6 and KDOC of D4 and D6 are the first reported. Polyparameter linear free energy relationships (PP-LFERs) derived from training sets of empirical data that did not include cVMS generally did not predict our measured partition ratios of cVMS accurately (root-mean-squared-error (RMSE) for logKOC 0.76 and for logKDOC 0.73). We constructed new PP-LFERs that accurately describe partition ratios for the cVMS as well as for other chemicals by including our new measurements in the existing training sets (logKOC RMSEcVMS: 0.09, logKDOC RMSEcVMS: 0.12). The PP-LFERs we have developed here should be further evaluated and perhaps recalibrated when experimental data for other siloxanes become available.

  12. Intuitionistic uncertain linguistic partitioned Bonferroni means and their application to multiple attribute decision-making

    Science.gov (United States)

    Liu, Zhengmin; Liu, Peide

    2017-04-01

    The Bonferroni mean (BM) was originally introduced by Bonferroni and generalised by many other researchers due to its capacity to capture the interrelationship between input arguments. Nevertheless, in many situations, interrelationships do not always exist between all of the attributes. Attributes can be partitioned into several different categories and members of intra-partition are interrelated while no interrelationship exists between attributes of different partitions. In this paper, as complements to the existing generalisations of BM, we investigate the partitioned Bonferroni mean (PBM) under intuitionistic uncertain linguistic environments and develop two linguistic aggregation operators: intuitionistic uncertain linguistic partitioned Bonferroni mean (IULPBM) and its weighted form (WIULPBM). Then, motivated by the ideal of geometric mean and PBM, we further present the partitioned geometric Bonferroni mean (PGBM) and develop two linguistic geometric aggregation operators: intuitionistic uncertain linguistic partitioned geometric Bonferroni mean (IULPGBM) and its weighted form (WIULPGBM). Some properties and special cases of these proposed operators are also investigated and discussed in detail. Based on these operators, an approach for multiple attribute decision-making problems with intuitionistic uncertain linguistic information is developed. Finally, a practical example is presented to illustrate the developed approach and comparison analyses are conducted with other representative methods to verify the effectiveness and feasibility of the developed approach.

  13. Countering oversegmentation in partitioning-based connectivities

    NARCIS (Netherlands)

    Ouzounis, Georgios K.; Wilkinson, Michael H.F.

    2005-01-01

    A new theoretical development is presented for handling the over-segmentation problem in partitioning-based connected openings. The definition we propose treats singletons generated with the earlier method, as elements of a larger connected component. Unlike the existing formalism, this new method

  14. Protium, an infrastructure for partitioned applications

    NARCIS (Netherlands)

    Young, Cliff; Lakshman, Y.N.; Szymanski, Tom; Reppy, John; Presotto, David; Pike, Rob; Narlikar, Girija; Mullender, Sape; Grosse, Eric

    Remote access feels different from local access. The major issues are consistency (machines vary in GUIs, applications, and devices) and responsiveness (the user must wait for network and server delays). Protium attacks these by partitioning programs into local viewers that connect to remote

  15. A dynamic re-partitioning strategy based on the distribution of key in Spark

    Science.gov (United States)

    Zhang, Tianyu; Lian, Xin

    2018-05-01

    Spark is a memory-based distributed data processing framework, has the ability of processing massive data and becomes a focus in Big Data. But the performance of Spark Shuffle depends on the distribution of data. The naive Hash partition function of Spark can not guarantee load balancing when data is skewed. The time of job is affected by the node which has more data to process. In order to handle this problem, dynamic sampling is used. In the process of task execution, histogram is used to count the key frequency distribution of each node, and then generate the global key frequency distribution. After analyzing the distribution of key, load balance of data partition is achieved. Results show that the Dynamic Re-Partitioning function is better than the default Hash partition, Fine Partition and the Balanced-Schedule strategy, it can reduce the execution time of the task and improve the efficiency of the whole cluster.

  16. Influence of biochar on isoproturon partitioning and bioaccessibility in soil

    International Nuclear Information System (INIS)

    Reid, B.J.; Pickering, F.L.; Freddo, A.; Whelan, M.J.; Coulon, F.

    2013-01-01

    The influence of biochar (5%) on the loss, partitioning and bioaccessibility of 14 C-isoproturon ( 14 C-IPU) was evaluated. Results indicated that biochar had a dramatic effect upon 14 C-IPU partitioning: 14 C-IPU extractability (0.01 M CaCl 2 ) in biochar-amended treatments was reduced to 14 C-IPU extractability in biochar free treatments decreased with ageing from 90% to 40%. A partitioning model was constructed to derive an effective partition coefficient for biochar:water (K BW of 7.82 × 10 4 L kg −1 ). This was two orders of magnitude greater than the apparent K foc value of the soil organic carbon:water (631 L kg −1 ). 14 C-radiorespirometry assays indicated high competence of microorganisms to mineralise 14 C-IPU in the absence of biochar (40.3 ± 0.9%). Where biochar was present 14 C-IPU mineralisation never exceeded 2%. These results indicate reduced herbicide bioaccessibility. Increasing IPU application to ×10 its recommended dose was ineffective at redressing IPU sequestration and its low bioaccessibility. Highlights: •Biochar had a dramatic effect on IPU partitioning. •IPU extractability was reduced to BW ) was 7.82 × 10 4 L kg −1 . •K BW was 124 times greater than the apparent K foc value of the control. •Biochar precluded microbial bioaccessibility – no catabolic response was observed. -- Biochar dramatically reduced 14 C-IPU extractability ( BW being ×123 greater than the apparent K foc . Correspondingly, microbial bioaccessibility of IPU was negligible

  17. Deformation Partitioning: The Missing Link Between Outcrop-Scale Observations And Orogen-Scale Processes

    Science.gov (United States)

    Attia, S.; Paterson, S. R.; Jiang, D.; Miller, R. B.

    2017-12-01

    Structural studies of orogenic deformation fields are mostly based on small-scale structures ubiquitous in field exposures, hand samples, and under microscopes. Relating deformation histories derived from such structures to changing lithospheric-scale deformation and boundary conditions is not trivial due to vast scale separation (10-6 107 m) between characteristic lengths of small-scale structures and lithospheric plates. Rheological heterogeneity over the range of orogenic scales will lead to deformation partitioning throughout intervening scales of structural development. Spectacular examples of structures documenting deformation partitioning are widespread within hot (i.e., magma-rich) orogens such as the well-studied central Sierra Nevada and Cascades core of western North America: (1) deformation partitioned into localized, narrow, triclinic shear zones separated by broad domains of distributed pure shear at micro- to 10 km scales; (2) deformation partitioned between plutons and surrounding metamorphic host rocks as shown by pluton-wide magmatic fabrics consistently oriented differently than coeval host rock fabrics; (3) partitioning recorded by different fabric intensities, styles, and orientations established from meter-scale grid mapping to 100 km scale domainal analyses; and (4) variations in the causes of strain and kinematics within fold-dominated domains. These complex, partitioned histories require synthesized mapping, geochronology, and structural data at all scales to evaluate partitioning and in the absence of correct scaling can lead to incorrect interpretations of histories. Forward modeling capable of addressing deformation partitioning in materials containing multiple scales of rheologically heterogeneous elements of varying characteristic lengths provides the ability to upscale the large synthesized datasets described above to plate-scale tectonic processes and boundary conditions. By comparing modeling predictions from the recently developed

  18. Dual little strings and their partition functions

    Science.gov (United States)

    Bastian, Brice; Hohenegger, Stefan; Iqbal, Amer; Rey, Soo-Jong

    2018-05-01

    We study the topological string partition function of a class of toric, double elliptically fibered Calabi-Yau threefolds XN ,M at a generic point in the Kähler moduli space. These manifolds engineer little string theories in five dimensions or lower and are dual to stacks of M5-branes probing a transverse orbifold singularity. Using the refined topological vertex formalism, we explicitly calculate a generic building block which allows us to compute the topological string partition function of XN ,M as a series expansion in different Kähler parameters. Using this result, we give further explicit proof for a duality found previously in the literature, which relates XN ,M˜XN',M' for N M =N'M' and gcd (N ,M )=gcd (N',M') .

  19. Parallel Processing of Big Point Clouds Using Z-Order Partitioning

    Science.gov (United States)

    Alis, C.; Boehm, J.; Liu, K.

    2016-06-01

    As laser scanning technology improves and costs are coming down, the amount of point cloud data being generated can be prohibitively difficult and expensive to process on a single machine. This data explosion is not only limited to point cloud data. Voluminous amounts of high-dimensionality and quickly accumulating data, collectively known as Big Data, such as those generated by social media, Internet of Things devices and commercial transactions, are becoming more prevalent as well. New computing paradigms and frameworks are being developed to efficiently handle the processing of Big Data, many of which utilize a compute cluster composed of several commodity grade machines to process chunks of data in parallel. A central concept in many of these frameworks is data locality. By its nature, Big Data is large enough that the entire dataset would not fit on the memory and hard drives of a single node hence replicating the entire dataset to each worker node is impractical. The data must then be partitioned across worker nodes in a manner that minimises data transfer across the network. This is a challenge for point cloud data because there exist different ways to partition data and they may require data transfer. We propose a partitioning based on Z-order which is a form of locality-sensitive hashing. The Z-order or Morton code is computed by dividing each dimension to form a grid then interleaving the binary representation of each dimension. For example, the Z-order code for the grid square with coordinates (x = 1 = 012, y = 3 = 112) is 10112 = 11. The number of points in each partition is controlled by the number of bits per dimension: the more bits, the fewer the points. The number of bits per dimension also controls the level of detail with more bits yielding finer partitioning. We present this partitioning method by implementing it on Apache Spark and investigating how different parameters affect the accuracy and running time of the k nearest neighbour algorithm

  20. Optimization of Time-Partitions for Mixed-Criticality Real-Time Distributed Embedded Systems

    DEFF Research Database (Denmark)

    Tamas-Selicean, Domitian; Pop, Paul

    2011-01-01

    In this paper we are interested in mixed-criticality embedded real-time applications mapped on distributed heterogeneous architectures. The architecture provides both spatial and temporal partitioning, thus enforcing enough separation for the critical applications. With temporal partitioning, each...

  1. Quenching and partitioning treatment of a low-carbon martensitic stainless steel

    International Nuclear Information System (INIS)

    Tsuchiyama, Toshihiro; Tobata, Junya; Tao, Teruyuki; Nakada, Nobuo; Takaki, Setsuo

    2012-01-01

    Highlights: ► The amount of retained austenite was increased by Q and P treatment in 12Cr–0.1C steel. ► Ideal carbon concentrations in austenite and ferrite were calculated assuming CCE condition. ► The optimum partitioning treatment condition for 12Cr–0.1C steel was found. ► The strength–ductility balance of 12Cr–0.1C steel was improved by TRIP effect. - Abstract: Quenching and partitioning (Q and P) treatment was applied to a commercial low-carbon martensitic stainless steel, AISI Type 410 (Fe–12Cr–0.1C). The quench interruption temperature was optimized with consideration of the ideal carbon concentration in untransformed austenite after partitioning to lower the Ms temperature to room temperature. After partitioning at an appropriate temperature, a significant fraction of austenite was retained through the enrichment of carbon into the untransformed austenite. It was also suggested that the addition of silicon is not necessarily required for the Q and P treatment of 12Cr steel because of the retardation of carbide precipitation at the partitioning temperature owing to the large amount of chromium. Tensile testing revealed that the Q and P-treated material exhibited a significantly improved strength–ductility balance compared with conventional quench-and-tempered materials due to the transformation-induced plasticity (TRIP) effect by the retained austenite.

  2. Quenching and partitioning treatment of a low-carbon martensitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchiyama, Toshihiro, E-mail: toshi@zaiko.kyushu-u.ac.jp [Department of Materials Science and Engineering, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Tobata, Junya; Tao, Teruyuki [Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Nakada, Nobuo; Takaki, Setsuo [Department of Materials Science and Engineering, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer The amount of retained austenite was increased by Q and P treatment in 12Cr-0.1C steel. Black-Right-Pointing-Pointer Ideal carbon concentrations in austenite and ferrite were calculated assuming CCE condition. Black-Right-Pointing-Pointer The optimum partitioning treatment condition for 12Cr-0.1C steel was found. Black-Right-Pointing-Pointer The strength-ductility balance of 12Cr-0.1C steel was improved by TRIP effect. - Abstract: Quenching and partitioning (Q and P) treatment was applied to a commercial low-carbon martensitic stainless steel, AISI Type 410 (Fe-12Cr-0.1C). The quench interruption temperature was optimized with consideration of the ideal carbon concentration in untransformed austenite after partitioning to lower the Ms temperature to room temperature. After partitioning at an appropriate temperature, a significant fraction of austenite was retained through the enrichment of carbon into the untransformed austenite. It was also suggested that the addition of silicon is not necessarily required for the Q and P treatment of 12Cr steel because of the retardation of carbide precipitation at the partitioning temperature owing to the large amount of chromium. Tensile testing revealed that the Q and P-treated material exhibited a significantly improved strength-ductility balance compared with conventional quench-and-tempered materials due to the transformation-induced plasticity (TRIP) effect by the retained austenite.

  3. Supersymmetric partition functions and the three-dimensional A-twist

    Energy Technology Data Exchange (ETDEWEB)

    Closset, Cyril [Theory Department, CERN,CH-1211, Geneva 23 (Switzerland); Kim, Heeyeon [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, N2L 2Y5, Ontario (Canada); Willett, Brian [Kavli Institute for Theoretical Physics, University of California,Santa Barbara, CA 93106 (United States)

    2017-03-14

    We study three-dimensional N=2 supersymmetric gauge theories on M{sub g,p}, an oriented circle bundle of degree p over a closed Riemann surface, Σ{sub g}. We compute the M{sub g,p} supersymmetric partition function and correlation functions of supersymmetric loop operators. This uncovers interesting relations between observables on manifolds of different topologies. In particular, the familiar supersymmetric partition function on the round S{sup 3} can be understood as the expectation value of a so-called “fibering operator” on S{sup 2}×S{sup 1} with a topological twist. More generally, we show that the 3d N=2 supersymmetric partition functions (and supersymmetric Wilson loop correlation functions) on M{sub g,p} are fully determined by the two-dimensional A-twisted topological field theory obtained by compactifying the 3d theory on a circle. We give two complementary derivations of the result. We also discuss applications to F-maximization and to three-dimensional supersymmetric dualities.

  4. Aqueous-gas phase partitioning and hydrolysis of organic iodides

    International Nuclear Information System (INIS)

    Glowa, G.A.; Wren, J.C.

    2003-01-01

    The volatility and decomposition of organic iodides in a reactor containment building are important parameters to consider when assessing the potential consequences of a nuclear reactor accident. However, there are few experimental data available for the volatilities (often reported as partition coefficients) or few rate constants regarding the decomposition (via hydrolysis) of organic iodides. The partition coefficients and hydrolysis rate constants of eight organic iodides, having a range of molecular structures, have been measured in the current studies. This data, and data accumulated in the literature, have been reviewed and discussed to provide guidelines for appropriate organization of organic iodides for the purpose of modelling iodine behaviour under postulated nuclear reactor accident conditions. After assessment of the partition coefficients and their temperature dependences of many classes of organic compounds, it was found that organic iodides could be divided into two categories based upon their volatility relative to molecular iodine. Similarly, hydrolysis rates and their temperature dependences are assigned to the two categories of organic iodides. (author)

  5. Gate-tunable current partition in graphene-based topological zero lines

    Science.gov (United States)

    Wang, Ke; Ren, Yafei; Deng, Xinzhou; Yang, Shengyuan A.; Jung, Jeil; Qiao, Zhenhua

    2017-06-01

    We demonstrate new mechanisms for gate-tunable current partition at topological zero-line intersections in a graphene-based current splitter. Based on numerical calculations of the nonequilibrium Green's functions and Landauer-Büttiker formula, we show that the presence of a perpendicular magnetic field on the order of a few Teslas allows for carrier sign dependent current routing. In the zero-field limit the control on current routing and partition can be achieved within a range of 10-90 % of the total incoming current by tuning the carrier density at tilted intersections or by modifying the relative magnitude of the bulk band gaps via gate voltage. We discuss the implications of our findings in the design of topological zero-line networks where finite orbital magnetic moments are expected when the current partition is asymmetric.

  6. Domain wall partition functions and KP

    International Nuclear Information System (INIS)

    Foda, O; Wheeler, M; Zuparic, M

    2009-01-01

    We observe that the partition function of the six-vertex model on a finite square lattice with domain wall boundary conditions is (a restriction of) a KP τ function and express it as an expectation value of charged free fermions (up to an overall normalization)

  7. The role of consumer satisfaction, consideration set size, variety seeking and convenience orientation in explaining seafood consumption in Vietnam

    OpenAIRE

    Ninh, Thi Kim Anh

    2010-01-01

    The study examines the relationship betweens convenience food and seafood consumption in Vietnam through a replication and an extension of studies of Rortveit and Olsen (2007; 2009). The main purpose of this study is to give an understanding of the role of consumers’ satisfaction, consideration set size, variety seeking, and convenience in explaining seafood consumption behavior in Vietnam.

  8. Partitioning-transmutation technology: a potential future nuclear waste management option

    International Nuclear Information System (INIS)

    Nakayama, S.; Morita, Y.; Nishihara, K.; Oigawa, H.

    2005-01-01

    Partitioning-transmutation technology (PT) will produce radioactive wastes of different physical and chemical properties and in different amounts from those generated in the current nuclear fuel cycle. To assess quantitatively the effects of PT on waste disposal, we first analyzed the amounts of the PT wastes, assumed conditioning for each type of the waste, and then made an attempt to estimate the repository area for disposal of the PT wastes. The properties of the hot Sr-Cs waste form are controlling factors in determining the size of the geologic repository. The disposal area could be reduced if the Sr-Cs fraction is disposed in a different subsurface repository or by long-term storage of the waste under institutional control. Disposal in a subsurface repository was found to comply with the Japanese law in terms of radioactivity constraint, through a performance assessment for disposal of the Sr-Cs fraction. (authors)

  9. EUROPART: an European integrated project on actinide partitioning

    International Nuclear Information System (INIS)

    Madic, C.; Baron, P.; Hudson, M.J.

    2006-01-01

    Full text of publication follows: The EUROPART project is a scientific integrated project between 24 European partners, from 10 countries, mostly funded by the European Community within the FP6, together with CRIEPI from Japan and ANSTO from Australia. EUROPART aims at developing chemical partitioning processes for the so-called minor actinides (MA) contained in nuclear wastes, i.e. from Am to Cf. In the case of the treatment of dedicated spent fuels or targets, the actinides to be separated also include U, Pu and Np. The techniques considered for the separation of these radionuclides belong to the fields of hydrometallurgy and pyrometallurgy, as in the previous European FP5 programs named PARTNEW, CALIXPART and PYROREP, respectively. The two main axes of research within EUROPART are: 1/ the partitioning of MA (from Am to Cf) from wastes issuing from the reprocessing of high burn-up UOX fuels and multi-recycled MOX fuels, 2/ the partitioning of the whole actinide family of elements for recycling, as an option for advanced dedicated fuel cycles (this work will be connected to the studies to be performed within the EUROTRANS European integrated project). In hydrometallurgy, the research is organized in five Work Packages (WP). Four are dedicated to the study of partitioning methods mainly based on the use of solvent extraction methods and of solid extractants, one WP is dedicated to the development of actinide co-conversion methods for fuel or target preparations. The research in pyrometallurgy is organized into four WPs, listed hereafter: (i) study of the basic chemistry of transuranium elements and of some fission products in molten salts (chlorides, fluorides), (ii) development of actinide partitioning methods, (iii) study of the conditioning of the salt wastes, (iv) system studies. Moreover, a strong management team is concerned not only with the technical and financial issues arising from EUROPART, but also with information, communication and benefits for Europe

  10. Comparison of Heuristics for Generating All-partition Arrays in the Style of Milton Babbitt

    DEFF Research Database (Denmark)

    Bemman, Brian; Meredith, David

    2015-01-01

    aggregate or an incomplete one that can be made complete by adding OARPs. It is noteworthy that, when constructing an all-partition array, Babbitt started out with a non-self-contained sequence of partitions. In this paper, we use a known self-contained sequence as a basis for forming two heuristics...... that select integer partitions likely to have been chosen by Babbitt. We suggest these heuristics will select integer partitions more likely to produce a self-contained sequence and we present it as a means for efficiently searching the space of possible sequences. We apply our heuristics to both types...

  11. Nitro-polycyclic aromatic hydrocarbons - gas-particle partitioning, mass size distribution, and formation along transport in marine and continental background air

    Science.gov (United States)

    Lammel, Gerhard; Mulder, Marie D.; Shahpoury, Pourya; Kukučka, Petr; Lišková, Hana; Přibylová, Petra; Prokeš, Roman; Wotawa, Gerhard

    2017-05-01

    Nitro-polycyclic aromatic hydrocarbons (NPAH) are ubiquitous in polluted air but little is known about their abundance in background air. NPAHs were studied at one marine and one continental background site, i.e. a coastal site in the southern Aegean Sea (summer 2012) and a site in the central Great Hungarian Plain (summer 2013), together with the parent compounds, PAHs. A Lagrangian particle dispersion model was used to track air mass history. Based on Lagrangian particle statistics, the urban influence on samples was quantified for the first time as a fractional dose to which the collected volume of air had been exposed. At the remote marine site, the 3-4-ring NPAH (sum of 11 targeted species) concentration was 23.7 pg m-3 while the concentration of 4-ring PAHs (6 species) was 426 pg m-3. The most abundant NPAHs were 2-nitrofluoranthene (2NFLT) and 3-nitrophenanthrene. Urban fractional doses in the range of air are the lowest ever reported and remarkably lower, by more than 1 order of magnitude, than 1 decade before. Day-night variation of NPAHs at the continental site reflected shorter lifetime during the day, possibly because of photolysis of some NPAHs. The yields of formation of 2NFLT and 2-nitropyrene (2NPYR) in marine air seem to be close to the yields for OH-initiated photochemistry observed in laboratory experiments under high NOx conditions. Good agreement is found for the prediction of NPAH gas-particle partitioning using a multi-phase poly-parameter linear free-energy relationship. Sorption to soot is found to be less significant for gas-particle partitioning of NPAHs than for PAHs. The NPAH levels determined in the south-eastern outflow of Europe confirm intercontinental transport potential.

  12. Monomial Crystals and Partition Crystals

    Science.gov (United States)

    Tingley, Peter

    2010-04-01

    Recently Fayers introduced a large family of combinatorial realizations of the fundamental crystal B(Λ0) for ^sln, where the vertices are indexed by certain partitions. He showed that special cases of this construction agree with the Misra-Miwa realization and with Berg's ladder crystal. Here we show that another special case is naturally isomorphic to a realization using Nakajima's monomial crystal.

  13. Partitioning,Automation and Error Recovery in the Control and Monitoring System of an LHC Experiment

    Institute of Scientific and Technical Information of China (English)

    C.Gaspar

    2001-01-01

    The Joint Controls Project(JCOP)is a collaboration between CERN and the four LHC experiments to find and implement common solutions for their control and monitoring systems.As part of this project and Architecture Working Group was set up in order to study the requirements and devise an architectural model that would suit the four experiments.Many issues were studied by this working group:Alarm handling,Access Control,Hierarchical Control,etc.This paper will report on the specific issue of hierarchical control and in particular partitioning,automation and error recovery.

  14. Equilibrium thermodynamics of the partitioning of non-steroidal anti-inflammatory drugs into human erythrocyte ghost membranes

    International Nuclear Information System (INIS)

    Omran, Ahmed A.

    2013-01-01

    Graphical abstract: Bar diagram representing thermodynamic parameters obtained for the partitioning of NSAIDs into human erythrocyte ghost membranes at physiological pH; 7.4. Highlights: • Partition coefficients of NSAIDs into HEG membranes were determined. • Thermodynamic parameters were evaluated and successfully analyzed. • Partitioning of NSAIDs into HEG membranes was exothermic. • Partitioning of NSAIDs into HEG is spontaneous with negative free energy values. • Identical partitioning enthalpy–entropy driven compensation mechanism was shown. -- Abstract: In this work,second derivative spectrophotometry was applied for determining the partition coefficients (K p s) of four non-steroidal anti-inflammatory drugs (NSAIDs; flufenamic, meclofenamic, mefenamic and niflumic acids) into human erythrocyte ghost (HEG) membranes over a temperature range from (283.2 to 313.2) K. The proposed method allowed the evaluation and direct analyses of thermodynamic parameters; enthalpy (ΔH W→M ), Gibbs energy (ΔG W→M ) and entropy (ΔS W→M ) changes of the partitioning of NSAIDs into HEG membranes. The partitioning of NSAIDs between polar aqueous phase and non-polar lipid bilayer HEG membrane phase was exothermic with negative (ΔH W→M ) which compensated for the changes in (ΔS W→M ). The negative values of (ΔG W→M ) revealed that the partitioning of NSAIDs into HEG, owing to their transfer from polar aqueous phase and non-polar HEG phase is spontaneous. The enthalpy–entropy correlation analysis resulted in a good linearity that suggests an identical partitioning enthalpy–entropy driven compensation mechanism for the studied NSAIDs

  15. Gait Partitioning Methods: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Juri Taborri

    2016-01-01

    Full Text Available In the last years, gait phase partitioning has come to be a challenging research topic due to its impact on several applications related to gait technologies. A variety of sensors can be used to feed algorithms for gait phase partitioning, mainly classifiable as wearable or non-wearable. Among wearable sensors, footswitches or foot pressure insoles are generally considered as the gold standard; however, to overcome some inherent limitations of the former, inertial measurement units have become popular in recent decades. Valuable results have been achieved also though electromyography, electroneurography, and ultrasonic sensors. Non-wearable sensors, such as opto-electronic systems along with force platforms, remain the most accurate system to perform gait analysis in an indoor environment. In the present paper we identify, select, and categorize the available methodologies for gait phase detection, analyzing advantages and disadvantages of each solution. Finally, we comparatively examine the obtainable gait phase granularities, the usable computational methodologies and the optimal sensor placements on the targeted body segments.

  16. Gait Partitioning Methods: A Systematic Review

    Science.gov (United States)

    Taborri, Juri; Palermo, Eduardo; Rossi, Stefano; Cappa, Paolo

    2016-01-01

    In the last years, gait phase partitioning has come to be a challenging research topic due to its impact on several applications related to gait technologies. A variety of sensors can be used to feed algorithms for gait phase partitioning, mainly classifiable as wearable or non-wearable. Among wearable sensors, footswitches or foot pressure insoles are generally considered as the gold standard; however, to overcome some inherent limitations of the former, inertial measurement units have become popular in recent decades. Valuable results have been achieved also though electromyography, electroneurography, and ultrasonic sensors. Non-wearable sensors, such as opto-electronic systems along with force platforms, remain the most accurate system to perform gait analysis in an indoor environment. In the present paper we identify, select, and categorize the available methodologies for gait phase detection, analyzing advantages and disadvantages of each solution. Finally, we comparatively examine the obtainable gait phase granularities, the usable computational methodologies and the optimal sensor placements on the targeted body segments. PMID:26751449

  17. Partitioning and transmutation. Annual Report 1999

    Energy Technology Data Exchange (ETDEWEB)

    Ekberg, C.; Enarsson, Aa.; Gustavsson, C.; Landgren, A.; Liljenzin, J.O.; Spjuth, L. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Nuclear Chemistry

    2000-05-01

    The current research project on partitioning and transmutation at the Dept. of Nuclear Chemistry, CTH, has the primary objective to investigate separation processes useful in connection with transmutation of long-lived radionuclides in high level nuclear waste. Partitioning is necessary in order to recover and purify the elements before and after each irradiation in a P and T treatment. In order to achieve a high transmutation efficiency the chemical separation process used must have small losses to various waste streams. At present, only aqueous based separation processes are known to be able to achieve the high recovery and separation efficiencies necessary for a useful P and T process. During 1999 two of the three PhD students in this project have finalised their dissertations. Lena Spjuth has been working with oligo pyridines, triazines and malonamides; Anders Landgren has studied Aliquat-336 and redox kinetics. Two papers, included as appendices in the report, have been separately indexed.

  18. Partitioning and transmutation. Annual Report 1999

    International Nuclear Information System (INIS)

    Ekberg, C.; Enarsson, Aa.; Gustavsson, C.; Landgren, A.; Liljenzin, J.O.; Spjuth, L.

    2000-05-01

    The current research project on partitioning and transmutation at the Dept. of Nuclear Chemistry, CTH, has the primary objective to investigate separation processes useful in connection with transmutation of long-lived radionuclides in high level nuclear waste. Partitioning is necessary in order to recover and purify the elements before and after each irradiation in a P and T treatment. In order to achieve a high transmutation efficiency the chemical separation process used must have small losses to various waste streams. At present, only aqueous based separation processes are known to be able to achieve the high recovery and separation efficiencies necessary for a useful P and T process. During 1999 two of the three PhD students in this project have finalised their dissertations. Lena Spjuth has been working with oligo pyridines, triazines and malonamides; Anders Landgren has studied Aliquat-336 and redox kinetics. Two papers, included as appendices in the report, have been separately indexed

  19. Coupled metal partitioning dynamics and toxicodynamics at biointerfaces: a theory beyond the biotic ligand model framework.

    Science.gov (United States)

    Duval, Jérôme F L

    2016-04-14

    A mechanistic understanding of the processes governing metal toxicity to microorganisms (bacteria, algae) calls for an adequate formulation of metal partitioning at biointerfaces during cell exposure. This includes the account of metal transport dynamics from bulk solution to biomembrane and the kinetics of metal internalisation, both potentially controlling the intracellular and surface metal fractions that originate cell growth inhibition. A theoretical rationale is developed here for such coupled toxicodynamics and interfacial metal partitioning dynamics under non-complexing medium conditions with integration of the defining cell electrostatic properties. The formalism explicitly considers intertwined metal adsorption at the biointerface, intracellular metal excretion, cell growth and metal depletion from bulk solution. The theory is derived under relevant steady-state metal transport conditions on the basis of coupled Nernst-Planck equation and continuous logistic equation modified to include metal-induced cell growth inhibition and cell size changes. Computational examples are discussed to identify limitations of the classical Biotic Ligand Model (BLM) in evaluating metal toxicity over time. In particular, BLM is shown to severely underestimate metal toxicity depending on cell exposure time, metal internalisation kinetics, cell surface electrostatics and initial cell density. Analytical expressions are provided for the interfacial metal concentration profiles in the limit where cell-growth is completely inhibited. A rigorous relationship between time-dependent cell density and metal concentrations at the biosurface and in bulk solution is further provided, which unifies previous equations formulated by Best and Duval under constant cell density and cell size conditions. The theory is sufficiently flexible to adapt to toxicity scenarios with involved cell survival-death processes.

  20. An Adaptation of the Kernighan-Lin Heuristic to the Simple Graph Partitioning Problem

    DEFF Research Database (Denmark)

    Sørensen, Michael Malmros

    1999-01-01

    to this problem of the Kernighan-Lin exchange heuristic, which was originally developed for the closely related 2-partition problem. The evaluation is carried out on problem instances on graphs with up to 50 nodes for which the optimal partition values are known or upper bounds are available. The computational...... results show that among all instances with known optimal values the best partition values found by a randomized version of this heuristic lie well within 1% off the optimum....

  1. The influence of ration size on energetics and nitrogen retention in tilapia (Oreochromis niloticus)

    DEFF Research Database (Denmark)

    Skov, Peter Vilhelm; Duodu, Collins Prah; Adjei-Boateng, Daniel

    2017-01-01

    with ration size, feed conversion and protein retention were most efficient at ration sizes of 3%. Although the magnitude of the SDA response following feeding also increased with ration size, this was not proportionate to meal size. Therefore the metabolic cost of meal processing (SDA coefficient) was found......Proper nutrient management is essential for the environmental sustainability of aquaculture. While increasing daily rations generally may lead to improved growth rates, this does not necessarily mean that nutrients are utilized more efficiently. To investigate how ration size affects partitioning...... of dietary nutrient intake, the effects of meal size on growth and metabolism were examined in triplicate groups of adult Nile tilapia (Oreochromis niloticus) receiving daily rations corresponding to 1, 2, 3, or 4% of their biomass. While biomass gain and specific growth rates were positively correlated...

  2. Partitioning of L-methionine in aqueous two-phase systems containing poly(propylene glycol) and sodium phosphate salts

    International Nuclear Information System (INIS)

    Salabat, Alireza; Sadeghi, Rahmat; Moghadam, Somayeh Tiani; Jamehbozorg, Bahman

    2011-01-01

    Highlights: → Thermodynamics parameters for partitioning of L-methionine in ATPS. → Investigation of different effects on partition coefficient of the amino acid. → Propose the best condition for L-methionine partitioning. - Abstract: The partitioning behavior of L-methionine has been studied in aqueous two-phase systems of (poly(propylene glycol) + sodium phosphate salts + H 2 O) at different temperatures. The salts used were sodium di-hydrogen phosphate (NaH 2 PO 4 ), di-sodium hydrogen phosphate (Na 2 HPO 4 ) and tri-sodium phosphate (Na 3 PO 4 ). The effects of tie line length, salt type, and temperature on the partition coefficient of this amino acid have been studied. In addition, thermodynamic parameters (ΔH o , ΔS o and ΔG o ) as a function of temperature were calculated. The results showed that increasing tie line length led to decreasing of the partition coefficient. We also showed that the partition coefficients of the amino acid in the systems containing Na 3 PO 4 are greater than the other two salts. Moreover, it is verified that increasing temperature led to decreasing the partition coefficient. The experimental partition coefficient data are correlated using a modified virial-type model.

  3. Impact of partitioning and transmutation on the high level waste management

    International Nuclear Information System (INIS)

    Gonzalez-Romero, Enrique-Miguel

    2010-01-01

    The contribution is structured as follows: (i) Background on partitioning and transmutation; (ii) FP6 projects: RED-IMPACT; (iii) Advanced fuel cycle scenarios; (iv) Partitioning and transmutation expected performance; (v) Impact on the HLW thermal load; (vi) Impact on the deep geological disposal; and (vii) Impact on the performance assessment of deep geological disposal. (P.A.)

  4. Partitioning inter annual variability in net ecosystem exchange between climatic variability and functional change

    International Nuclear Information System (INIS)

    Hui, D.; Luo, Y.; Katul, G.

    2003-01-01

    Inter annual variability in net ecosystem exchange of carbon is investigated using a homogeneity-of-slopes model to identify the function change contributing to inter annual variability, net ecosystem carbon exchange, and night-time ecosystem respiration. Results of employing this statistical approach to a data set collected at the Duke Forest AmeriFlux site from August 1997 to December 2001 are discussed. The results demonstrate that it is feasible to partition the variation in ecosystem carbon fluxes into direct effects of seasonal and inter annual climatic variability and functional change. 51 refs., 4 tabs., 5 figs

  5. On the time evolution of holographic n-partite information

    International Nuclear Information System (INIS)

    Alishahiha, Mohsen; Mozaffar, M. Reza Mohammadi; Tanhayi, Mohammad Reza

    2015-01-01

    We study various scaling behaviors of n-partite information during a process of thermalization for n disjoint system consisting of n parallel strips whose widths are much larger than the separation between them. By making use of the holographic description for entanglement entropy we explore holographic description of the n-partite information by which we show that it has a definite sign: it is positive for even n and negative for odd n. This might thought of as an intrinsic property of a field theory which has gravity dual.

  6. Spatial distribution and partitioning behavior of selected poly- and perfluoroalkyl substances in freshwater ecosystems: A French nationwide survey

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, Gabriel; Giraudel, Jean-Luc [University of Bordeaux, EPOC, UMR 5805, LPTC, 351 Cours de la Libération, F-33400 Talence, France. (France); Botta, Fabrizio; Lestremau, François [INERIS, Parc Technologique Alata, BP2, 60550 Verneuil-en-Halatte, France. (France); Dévier, Marie-Hélène [University of Bordeaux, EPOC, UMR 5805, LPTC, 351 Cours de la Libération, F-33400 Talence, France. (France); Budzinski, Hélène [CNRS, EPOC, UMR 5805, LPTC, 351 Cours de la Libération, F-33400 Talence, France. (France); Labadie, Pierre, E-mail: pierre.labadie@u-bordeaux.fr [CNRS, EPOC, UMR 5805, LPTC, 351 Cours de la Libération, F-33400 Talence, France. (France)

    2015-06-01

    The spatial distribution and partitioning of 22 poly- and perfluoroalkyl substances (PFASs) in 133 selected rivers and lakes were investigated at a nationwide scale in mainland France. ΣPFASs was in the range < LOD–725 ng L{sup −1} in the dissolved phase (median: 7.9 ng L{sup −1}) and < LOD–25 ng g{sup −1} dry weight (dw) in the sediment (median: 0.48 ng g{sup −1} dw); dissolved PFAS levels were significantly lower at “reference” sites than at urban, rural or industrial sites. Although perfluorooctane sulfonate (PFOS) was found to be the prevalent compound on average, a multivariate analysis based on neural networks revealed noteworthy trends for other compounds at specific locations and, in some cases, at watershed scale. For instance, several sites along the Rhône River displayed a peculiar PFAS signature, perfluoroalkyl carboxylates (PFCAs) often dominating the PFAS profile (e.g., PFCAs > 99% of ΣPFASs in the sediment, likely as a consequence of industrial point source discharge). Several treatments for data below detection limits (non-detects) were used to compute descriptive statistics, differences among groups, and correlations between congeners, as well as log K{sub d} and log K{sub oc} partition coefficients; in that respect, the Regression on Order Statistics (robust ROS) method was preferred for descriptive statistics computation while the Akritas–Theil–Sen estimator was used for regression and correlation analyses. Multiple regression results suggest that PFAS levels in the dissolved phase and sediment characteristics (organic carbon fraction and grain size) may be significant controlling factors of PFAS levels in the sediment. - Highlights: • A large-scale survey of PFASs in 133 French rivers and lakes is reported. • Descriptive statistics, correlations and partitioning coefficients were determined. • Non-detects were taken into account using functions from the NADA R-package. • Hot spots of PFAS contamination were found

  7. Kinetic modeling of solid-state partitioning phase transformation with simultaneous misfit accommodation

    International Nuclear Information System (INIS)

    Song, Shaojie; Liu, Feng

    2016-01-01

    Considering a spherical misfitting precipitate growing into a finite elastic-perfectly plastic supersaturated matrix, a kinetic modeling for such solid-state partitioning phase transformation is presented, where the interactions of interface migration, solute diffusion and misfit accommodation are analyzed. The linkage between interface migration and solute diffusion proceeds through interfacial composition and interface velocity; their effects on misfit accommodation are mainly manifested in an effective transformation strain, which depends on instantaneous composition field and precipitate size. Taking γ to α transformation of a binary Fe-0.5 at.% C alloy under both isothermal and continuous cooling conditions as examples, the effects of misfit accommodation on the coupling interface migration and solute diffusion are well evaluated and discussed. For the isothermal transformation, a counterbalancing influence between mechanical and chemical driving forces is found so that the mixed-mode transformation kinetics is not sensitive with respect to the elastic–plastic accommodation of the effective misfit strain. Different from the isothermal process, during the continuous cooling condition, the effects of misfit accommodation on the kinetics of solid-state partitioning phase transformation are mainly manifested in the great decrease of the transformation starting temperature and the thermodynamic equilibrium composition. The present kinetic modeling was applied to predict the experimentally measured γ/α transformation of Fe-0.47 at.% C alloy conducted with a cooling rate of 10 K min −1 and a good agreement was achieved.

  8. Partition thermodynamics of ionic surfactants between phosphatidylcholine vesicle and water phases

    Science.gov (United States)

    Chu, Shin-Chi; Hung, Chia-Hui; Wang, Shun-Cheng; Tsao, Heng-Kwong

    2003-08-01

    The partition of ionic surfactants (sodium alkyl sulfate and alkyl trimethyl ammonium bromide) between phosphatidylcholine vesicles and aqueous phase is investigated by simple conductometry under different temperatures. The experimental results can be well represented by the proposed regular solution theory and the thermodynamic parameters satisfy the thermodynamic consistency. The deviation from ideal partition is manifested through the effective interaction energy between lipid and surfactant wb, which is O(kT) large. It is found that wb rises as the alkyl chain is decreased for a specified head group. This is attributed to significant mismatch of chain lengths between surfactant and lipid molecules. The partition coefficient K declines with increasing temperature. The energy barrier from bilayer to aqueous phase, Δμ/kT∝ln K, is in the range of 16-26 kJ/mol. As the alkyl chain length is decreased for a given head group, Δμ is lowered by 1.3-1.5 kJ/mol per methylene group. Two independent analyses are employed to confirm this result. Using the thermodynamic parameters determined from experiments, the internal energy, entropy, and free energy of the partition process can be derived. Partition is essentially driven by the internal energy gain. The solubilizing ability, which is represented by the maximum surfactant-lipid ratio in the bilayer, Reb also decreases in accord with the K parameter. It is because the change in temperature influences the surfactant incorporation into the bilayer more than the formation of micelles.

  9. 1-loop partition function in AdS{sub 3}/CFT{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Bin [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter,5 Yiheyuan Rd, Beijing 100871 (China); Center for High Energy Physics, Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Wu, Jie-qiang [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,5 Yiheyuan Rd, Beijing 100871 (China)

    2015-12-16

    The 1-loop partition function of the handlebody solutions in the AdS{sub 3} gravity have been derived some years ago using the heat kernel techniques and the method of images. In the semiclassical limit, such partition function should correspond to the order O(c{sup 0}) part in the partition function of dual conformal field theory(CFT) on the boundary Riemann surface. The higher genus partition function could be computed by the multi-point functions in the Riemann sphere via sewing prescription. In the large central charge limit, the CFT is effectively free in the sense that to the leading order of c the multi-point function is further simplified to be a summation over the products of two-point functions of single-particle states. Correspondingly in the bulk, the graviton is freely propagating without interaction. Furthermore the product of the two-point functions may define the links, each of which is in one-to-one correspondence with the conjugacy class of the Schottky group of the Riemann surface. Moreover, the value of a link is determined by the multiplier of the element in the conjugacy class. This allows us to reproduce exactly the gravitational 1-loop partition function. The proof can be generalized to the higher spin gravity and its dual CFT.

  10. INVESTIGATION INTO THE RATE OF TRIOCTYLAMINE PARTITIONING INTO THE MCU AQUEOUS PHASES

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T.; Couture, A.

    2013-07-16

    The Savannah River National Laboratory (SRNL) has examined the issue of trioctylamine (TOA) losses at the Modular Caustic-Side Solvent Extraction Unit (MCU) solvent. For this study, SRNL used partitioning and radiolysis data from the Oak Ridge National Laboratory (ORNL) as well as actual MCU operational data. From the radiolysis data, SRNL prepared a model on the rate of TOA degradation. From the combined sets of data, SRNL has calculated the largest possible value of TOA (although this value is not credible) in the Strip Effluent (SE) and also calculated two different conservative, more realistic values for TOA in the SE. Even under conservative assumptions, such as all of the TOA losses partitioning solely into the Strip Effluent (SE), the MCU operational data suggests that the maximum realistic TOA concentration in the SE is < 0.6 mg/L. Furthermore, from understanding the chemical differences between the old and new strip solutions, SRNL does not believe that the TOA will deplete from the blended BOBCalixC6 – Next Generation Solvent (NGS-MCU) at a rate higher than previously experienced. Finally, SRNL recommends pursuing analytical development of a method for TOA with a superior precision compared to the current method. However, as the TOA in the blended solvent will continuously decline during MCU operations, further improvements in the development of the understanding of TOA losses may not be cost effective.

  11. Partition function zeros of the one-dimensional Potts model: the recursive method

    International Nuclear Information System (INIS)

    Ghulghazaryan, R G; Ananikian, N S

    2003-01-01

    The Yang-Lee, Fisher and Potts zeros of the one-dimensional Q-state Potts model are studied using the theory of dynamical systems. An exact recurrence relation for the partition function is derived. It is shown that zeros of the partition function may be associated with neutral fixed points of the recurrence relation. Further, a general equation for zeros of the partition function is found and a classification of the Yang-Lee, Fisher and Potts zeros is given. It is shown that the Fisher zeros in a nonzero magnetic field are located on several lines in the complex temperature plane and that the number of these lines depends on the value of the magnetic field. Analytical expressions for the densities of the Yang-Lee, Fisher and Potts zeros are derived. It is shown that densities of all types of zeros of the partition function are singular at the edge singularity points with the same critical exponent

  12. Quantum corrections to Bekenstein–Hawking black hole entropy and gravity partition functions

    International Nuclear Information System (INIS)

    Bytsenko, A.A.; Tureanu, A.

    2013-01-01

    Algebraic aspects of the computation of partition functions for quantum gravity and black holes in AdS 3 are discussed. We compute the sub-leading quantum corrections to the Bekenstein–Hawking entropy. It is shown that the quantum corrections to the classical result can be included systematically by making use of the comparison with conformal field theory partition functions, via the AdS 3 /CFT 2 correspondence. This leads to a better understanding of the role of modular and spectral functions, from the point of view of the representation theory of infinite-dimensional Lie algebras. Besides, the sum of known quantum contributions to the partition function can be presented in a closed form, involving the Patterson–Selberg spectral function. These contributions can be reproduced in a holomorphically factorized theory whose partition functions are associated with the formal characters of the Virasoro modules. We propose a spectral function formulation for quantum corrections to the elliptic genus from supergravity states

  13. Complimentary analysis of metacommunity nestedness and diversity partitioning highlights the need for a holistic conservation strategy for highland lake fish assemblages

    Directory of Open Access Journals (Sweden)

    Jun Xu

    2015-01-01

    Full Text Available Metacommunity nestedness can be affected by both idiosyncratic species and species turnover, and diversity partitioning allows one to separate turnover and nested components within β-diversity. Thus, complimentary analysis of metacommunity nestedness and diversity partitioning allows for the identification of the underlying changes at both local and regional scales. We examined changes of fish assemblages in metacommunity nestedness and α-, β-, and γ-diversities resulting from the intense loss of native species and the invasion of nonnative species in Chinese highland lakes over the past 60 years. We found metacommunity nestedness rose markedly over time, following the loss of both β- and γ-diversity resulting from the loss of native species, and the increase of α diversity by the addition of nonnative species. This pattern is contradictory to the selective extinction leading to larger nestedness in natural ecosystems and indicates the human-induced negative effects on the metacommunity. However, β-diversity partitioning showed that the turnover component due to species replacement among lakes still contributes more than the nested component, suggesting the importance of avoiding setting conservation priorities based exclusively on metacommunity nestedness theory, but taking a more holistic metacommunity-approach to conservation instead.

  14. New polymers for low-gravity purification of cells by phase partitioning

    Science.gov (United States)

    Harris, J. M.

    1983-01-01

    A potentially powerful technique for separating different biological cell types is based on the partitioning of these cells between the immiscible aqueous phases formed by solution of certain polymers in water. This process is gravity-limited because cells sediment rather than associate with the phase most favored on the basis of cell-phase interactions. In the present contract we have been involved in the synthesis of new polymers both to aid in understanding the partitioning process and to improve the quality of separations. The prime driving force behind the design of these polymers is to produce materials which will aid in space experiments to separate important cell types and to study the partitioning process in the absence of gravity (i.e., in an equilibrium state).

  15. Partitioning of L-methionine in aqueous two-phase systems containing poly(propylene glycol) and sodium phosphate salts

    Energy Technology Data Exchange (ETDEWEB)

    Salabat, Alireza, E-mail: a-salabat@araku.ac.ir [Chemistry Department, Arak University, P.O. Box 38156-879, Arak (Iran, Islamic Republic of); Sadeghi, Rahmat [Department of Chemistry, University of Kurdistan, Sanandaj, Kurdistan 66135 (Iran, Islamic Republic of); Moghadam, Somayeh Tiani [Chemistry Department, Arak University, P.O. Box 38156-879, Arak (Iran, Islamic Republic of); Jamehbozorg, Bahman [Department of Chemistry, University of Kurdistan, Sanandaj, Kurdistan 66135 (Iran, Islamic Republic of)

    2011-10-15

    Highlights: > Thermodynamics parameters for partitioning of L-methionine in ATPS. > Investigation of different effects on partition coefficient of the amino acid. > Propose the best condition for L-methionine partitioning. - Abstract: The partitioning behavior of L-methionine has been studied in aqueous two-phase systems of (poly(propylene glycol) + sodium phosphate salts + H{sub 2}O) at different temperatures. The salts used were sodium di-hydrogen phosphate (NaH{sub 2}PO{sub 4}), di-sodium hydrogen phosphate (Na{sub 2}HPO{sub 4}) and tri-sodium phosphate (Na{sub 3}PO{sub 4}). The effects of tie line length, salt type, and temperature on the partition coefficient of this amino acid have been studied. In addition, thermodynamic parameters ({Delta}H{sup o}, {Delta}S{sup o} and {Delta}G{sup o}) as a function of temperature were calculated. The results showed that increasing tie line length led to decreasing of the partition coefficient. We also showed that the partition coefficients of the amino acid in the systems containing Na{sub 3}PO{sub 4} are greater than the other two salts. Moreover, it is verified that increasing temperature led to decreasing the partition coefficient. The experimental partition coefficient data are correlated using a modified virial-type model.

  16. In-situ ductile metal/bulk metallic glass matrix composites formed by chemical partitioning

    Science.gov (United States)

    Kim, Choong Paul; Hays, Charles C.; Johnson, William L.

    2004-03-23

    A composite metal object comprises ductile crystalline metal particles in an amorphous metal matrix. An alloy is heated above its liquidus temperature. Upon cooling from the high temperature melt, the alloy chemically partitions, forming dendrites in the melt. Upon cooling the remaining liquid below the glass transition temperature it freezes to the amorphous state, producing a two-phase microstructure containing crystalline particles in an amorphous metal matrix. The ductile metal particles have a size in the range of from 0.1 to 15 micrometers and spacing in the range of from 0.1 to 20 micrometers. Preferably, the particle size is in the range of from 0.5 to 8 micrometers and spacing is in the range of from 1 to 10 micrometers. The volume proportion of particles is in the range of from 5 to 50% and preferably 15 to 35%. Differential cooling can produce oriented dendrites of ductile metal phase in an amorphous matrix. Examples are given in the Zr--Ti--Cu--Ni--Be alloy bulk glass forming system with added niobium.

  17. A novel method for the determination of adsorption partition coefficients of minor gases in a shale sample by headspace gas chromatography.

    Science.gov (United States)

    Zhang, Chun-Yun; Hu, Hui-Chao; Chai, Xin-Sheng; Pan, Lei; Xiao, Xian-Ming

    2013-10-04

    A novel method has been developed for the determination of adsorption partition coefficient (Kd) of minor gases in shale. The method uses samples of two different sizes (masses) of the same material, from which the partition coefficient of the gas can be determined from two independent headspace gas chromatographic (HS-GC) measurements. The equilibrium for the model gas (ethane) was achieved in 5h at 120°C. The method also involves establishing an equation based on the Kd at higher equilibrium temperature, from which the Kd at lower temperature can be calculated. Although the HS-GC method requires some time and effort, it is simpler and quicker than the isothermal adsorption method that is in widespread use today. As a result, the method is simple and practical and can be a valuable tool for shale gas-related research and applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Numerical simulation of ventilation air movement in partitioned offices

    Energy Technology Data Exchange (ETDEWEB)

    Plett, E.G.; Soultogiannis, A.A.; Jouini, D.B. (Department of Mechanical and Aerospace Engineering, Carleton University, Ottawa, Ontario (Canada))

    1993-01-01

    Good air quality can only be assured throughout an office complex if each workspace receives an adequate supply of ventilation air. The likelihood of achieving this situation would be increased if the building engineer had a means of easily predicting the air movement in each office configuration. A simple computer-based solution to this need is proposed. To this end, the development and validation testing of a numerical solution technique to simulate the ventilation air movement in a room or office is described. The predictions of the two-dimensional, isothermal, inviscid formulation are seen to be in good agreement with experimentally measured airflows in configurations of interest. The computer code is then used to illustrate the airflow in offices served by a single row of supply air diffusers, when partitions are used to divide the space into smaller workspaces. It is observed that the partitions distort the airflow patterns to the extent that it would be difficult to provide desirable ventilation airflows to all the workspaces formed by the partitions. (au) (26 refs.)

  19. Commuting quantum circuits and complexity of Ising partition functions

    International Nuclear Information System (INIS)

    Fujii, Keisuke; Morimae, Tomoyuki

    2017-01-01

    Instantaneous quantum polynomial-time (IQP) computation is a class of quantum computation consisting only of commuting two-qubit gates and is not universal. Nevertheless, it has been shown that if there is a classical algorithm that can simulate IQP efficiently, the polynomial hierarchy collapses to the third level, which is highly implausible. However, the origin of the classical intractability is still less understood. Here we establish a relationship between IQP and computational complexity of calculating the imaginary-valued partition functions of Ising models. We apply the established relationship in two opposite directions. One direction is to find subclasses of IQP that are classically efficiently simulatable by using exact solvability of certain types of Ising models. Another direction is applying quantum computational complexity of IQP to investigate (im)possibility of efficient classical approximations of Ising partition functions with imaginary coupling constants. Specifically, we show that a multiplicative approximation of Ising partition functions is #P-hard for almost all imaginary coupling constants even on planar lattices of a bounded degree. (paper)

  20. Actinide Partitioning and Transmutation Program. Progress report, April 1--June 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Tedder, D. W.; Blomeke, J. O. [comps.

    1977-10-01

    Experimental work on the 16 tasks comprising the Actinide Partitioning and Transmutation Program was continued. Summaries of work are given on Purex Process modifications, actinide recovery, Am-Cm recovery, radiation effects on ion exchangers, LMFBR transmutation studies, thermal reactor transmutation studies, fuel cycle studies, and partitioning-transmutation evaluation. (JRD)

  1. Gas/particle partitioning behaviour of azaarenes in an urban atmosphere.

    Science.gov (United States)

    Chen, H Y; Preston, M R

    1997-01-01

    The gas/particle partitioning of azaarenes in the Liverpool urban atmosphere was measured from May 1995 to April 1996. This period included one of the hottest summers and coldest winters recorded in the UK. The changes of the relative proportions of particulate and vapour phases showed a strong seasonal variation in which over 80% of azaarene compounds are associated with the particles in the winter and over 60% of azaarene compounds exist as vapour phase during the summer. The results are fitted into a gas/particle partitioning equation. Calculated vapour pressures, vaporization and desorption enthalpies are also given. Azaarene partitioning behaviour is modelled at a variety of aerosol concentrations and over a temperature range which includes normal ambient temperatures. It is hypothesised that three ring azaarene species are more likely to undergo changes in the relative proportions of particle and vapour phase material than either two or four ring compounds.

  2. Uncertain Henry's law constants compromise equilibrium partitioning calculations of atmospheric oxidation products

    Directory of Open Access Journals (Sweden)

    C. Wang

    2017-06-01

    Full Text Available Gas–particle partitioning governs the distribution, removal, and transport of organic compounds in the atmosphere and the formation of secondary organic aerosol (SOA. The large variety of atmospheric species and their wide range of properties make predicting this partitioning equilibrium challenging. Here we expand on earlier work and predict gas–organic and gas–aqueous phase partitioning coefficients for 3414 atmospherically relevant molecules using COSMOtherm, SPARC Performs Automated Reasoning in Chemistry (SPARC, and poly-parameter linear free-energy relationships. The Master Chemical Mechanism generated the structures by oxidizing primary emitted volatile organic compounds. Predictions for gas–organic phase partitioning coefficients (KWIOM/G by different methods are on average within 1 order of magnitude of each other, irrespective of the numbers of functional groups, except for predictions by COSMOtherm and SPARC for compounds with more than three functional groups, which have a slightly higher discrepancy. Discrepancies between predictions of gas–aqueous partitioning (KW/G are much larger and increase with the number of functional groups in the molecule. In particular, COSMOtherm often predicts much lower KW/G for highly functionalized compounds than the other methods. While the quantum-chemistry-based COSMOtherm accounts for the influence of intra-molecular interactions on conformation, highly functionalized molecules likely fall outside of the applicability domain of the other techniques, which at least in part rely on empirical data for calibration. Further analysis suggests that atmospheric phase distribution calculations are sensitive to the partitioning coefficient estimation method, in particular to the estimated value of KW/G. The large uncertainty in KW/G predictions for highly functionalized organic compounds needs to be resolved to improve the quantitative treatment of SOA formation.

  3. Partitioning Behavior of Organic Contaminants in Carbon Storage Environments: A Critical Review

    Energy Technology Data Exchange (ETDEWEB)

    Burant, Aniela; Lowry, Gregory V; Karamalidis, Athanasios K

    2012-12-04

    Carbon capture and storage is a promising strategy for mitigating the CO{sub 2} contribution to global climate change. The large scale implementation of the technology mandates better understanding of the risks associated with CO{sub 2} injection into geologic formations and the subsequent interactions with groundwater resources. The injected supercritical CO{sub 2} (sc-CO{sub 2}) is a nonpolar solvent that can potentially mobilize organic compounds that exist at residual saturation in the formation. Here, we review the partitioning behavior of selected organic compounds typically found in depleted oil reservoirs in the residual oil–brine–sc-CO{sub 2} system under carbon storage conditions. The solubility of pure phase organic compounds in sc-CO{sub 2} and partitioning of organic compounds between water and sc-CO{sub 2} follow trends predicted based on thermodynamics. Compounds with high volatility and low aqueous solubility have the highest potential to partition to sc-CO{sub 2}. The partitioning of low volatility compounds to sc-CO{sub 2} can be enhanced by co-solvency due to the presence of higher volatility compounds in the sc-CO{sub 2}. The effect of temperature, pressure, salinity, pH, and dissolution of water molecules into sc-CO{sub 2} on the partitioning behavior of organic compounds in the residual oil-brine-sc-CO{sub 2} system is discussed. Data gaps and research needs for models to predict the partitioning of organic compounds in brines and from complex mixtures of oils are presented. Models need to be able to better incorporate the effect of salinity and co-solvency, which will require more experimental data from key classes of organic compounds.

  4. Scalable Partitioning Algorithms for FPGAs With Heterogeneous Resources

    National Research Council Canada - National Science Library

    Selvakkumaran, Navaratnasothie; Ranjan, Abhishek; Raje, Salil; Karypis, George

    2004-01-01

    As FPGA densities increase, partitioning-based FPGA placement approaches are becoming increasingly important as they can be used to provide high-quality and computationally scalable placement solutions...

  5. Kinetics of Solute Partitioning During Intercritical Annealing of a Medium-Mn Steel

    Science.gov (United States)

    Kamoutsi, H.; Gioti, E.; Haidemenopoulos, Gregory N.; Cai, Z.; Ding, H.

    2015-11-01

    The evolution of austenite fraction and solute partitioning (Mn, Al, and C) during intercritical annealing was calculated for a medium-Mn steel containing 11 pct Mn. Austenite growth takes place in three stages. The first stage is growth under non-partitioning local equilibrium (NPLE) controlled by carbon diffusion in ferrite. The second stage is growth under partitioning local equilibrium (PLE) controlled by diffusion of Mn in ferrite. The third stage is shrinkage of austenite under PLE controlled by diffusion of Mn in austenite. During PLE growth, the austenite is progressively enriched in Mn. Compositional spikes evolve early during NPLE growth and broaden with annealing temperature and time.

  6. Fuzzy 2-partition entropy threshold selection based on Big Bang–Big Crunch Optimization algorithm

    Directory of Open Access Journals (Sweden)

    Baljit Singh Khehra

    2015-03-01

    Full Text Available The fuzzy 2-partition entropy approach has been widely used to select threshold value for image segmenting. This approach used two parameterized fuzzy membership functions to form a fuzzy 2-partition of the image. The optimal threshold is selected by searching an optimal combination of parameters of the membership functions such that the entropy of fuzzy 2-partition is maximized. In this paper, a new fuzzy 2-partition entropy thresholding approach based on the technology of the Big Bang–Big Crunch Optimization (BBBCO is proposed. The new proposed thresholding approach is called the BBBCO-based fuzzy 2-partition entropy thresholding algorithm. BBBCO is used to search an optimal combination of parameters of the membership functions for maximizing the entropy of fuzzy 2-partition. BBBCO is inspired by the theory of the evolution of the universe; namely the Big Bang and Big Crunch Theory. The proposed algorithm is tested on a number of standard test images. For comparison, three different algorithms included Genetic Algorithm (GA-based, Biogeography-based Optimization (BBO-based and recursive approaches are also implemented. From experimental results, it is observed that the performance of the proposed algorithm is more effective than GA-based, BBO-based and recursion-based approaches.

  7. Human Rights and Peace Audit on Partition in South Asia - Phase I ...

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

    Human Rights and Peace Audit on Partition in South Asia - Phase I ... the South Asia Forum for Human Rights (SAFHR) to examine the efficacy of partition as a method ... Call for new OWSD Fellowships for Early Career Women Scientists now open ... IWRA/IDRC webinar on climate change and adaptive water management.

  8. Organic Matter Quality and Partitioning of Polychlorinated Biphenyls

    National Research Council Canada - National Science Library

    Brannon, James

    1997-01-01

    ...). Equilibrium partitioning of neutral organic chemicals between the organic carbon fraction of bedded sediments and the interstitial water of the sediments provides the theoretical basis for the most...

  9. Accelerating SPARQL queries by exploiting hash-based locality and adaptive partitioning

    KAUST Repository

    Al-Harbi, Razen

    2016-02-08

    State-of-the-art distributed RDF systems partition data across multiple computer nodes (workers). Some systems perform cheap hash partitioning, which may result in expensive query evaluation. Others try to minimize inter-node communication, which requires an expensive data preprocessing phase, leading to a high startup cost. Apriori knowledge of the query workload has also been used to create partitions, which, however, are static and do not adapt to workload changes. In this paper, we propose AdPart, a distributed RDF system, which addresses the shortcomings of previous work. First, AdPart applies lightweight partitioning on the initial data, which distributes triples by hashing on their subjects; this renders its startup overhead low. At the same time, the locality-aware query optimizer of AdPart takes full advantage of the partitioning to (1) support the fully parallel processing of join patterns on subjects and (2) minimize data communication for general queries by applying hash distribution of intermediate results instead of broadcasting, wherever possible. Second, AdPart monitors the data access patterns and dynamically redistributes and replicates the instances of the most frequent ones among workers. As a result, the communication cost for future queries is drastically reduced or even eliminated. To control replication, AdPart implements an eviction policy for the redistributed patterns. Our experiments with synthetic and real data verify that AdPart: (1) starts faster than all existing systems; (2) processes thousands of queries before other systems become online; and (3) gracefully adapts to the query load, being able to evaluate queries on billion-scale RDF data in subseconds.

  10. Estimating the Partition Function Zeros by Using the Wang-Landau Monte Carlo Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung-Yeon [Korea National University of Transportation, Chungju (Korea, Republic of)

    2017-03-15

    The concept of the partition function zeros is one of the most efficient methods for investigating the phase transitions and the critical phenomena in various physical systems. Estimating the partition function zeros requires information on the density of states Ω(E) as a function of the energy E. Currently, the Wang-Landau Monte Carlo algorithm is one of the best methods for calculating Ω(E). The partition function zeros in the complex temperature plane of the Ising model on an L × L square lattice (L = 10 ∼ 80) with a periodic boundary condition have been estimated by using the Wang-Landau Monte Carlo algorithm. The efficiency of the Wang-Landau Monte Carlo algorithm and the accuracies of the partition function zeros have been evaluated for three different, 5%, 10%, and 20%, flatness criteria for the histogram H(E).

  11. Criteria for genuine N -partite continuous-variable entanglement and Einstein-Podolsky-Rosen steering

    Science.gov (United States)

    Teh, R. Y.; Reid, M. D.

    2014-12-01

    Following previous work, we distinguish between genuine N -partite entanglement and full N -partite inseparability. Accordingly, we derive criteria to detect genuine multipartite entanglement using continuous-variable (position and momentum) measurements. Our criteria are similar but different to those based on the van Loock-Furusawa inequalities, which detect full N -partite inseparability. We explain how the criteria can be used to detect the genuine N -partite entanglement of continuous variable states generated from squeezed and vacuum state inputs, including the continuous-variable Greenberger-Horne-Zeilinger state, with explicit predictions for up to N =9 . This makes our work accessible to experiment. For N =3 , we also present criteria for tripartite Einstein-Podolsky-Rosen (EPR) steering. These criteria provide a means to demonstrate a genuine three-party EPR paradox, in which any single party is steerable by the remaining two parties.

  12. Two-loop superstring partition function

    International Nuclear Information System (INIS)

    Morozov, A.Y.

    1988-01-01

    Is it possible to choose the odd moduli on super-Riemann surfaces of genus p≥2 in such a way that the corresponding contributions to the superstring partition function vanish before the integration over the space of the moduli? It is shown that, at least for p = 2, the answer to this question is affirmative, and in this case the odd moduli should be localized at branch points

  13. Determination of octanol-water partition coefficients of polar polycyclic aromatic compounds (N-PAC) by high performance liquid chromatography

    DEFF Research Database (Denmark)

    Helweg, C.; Nielsen, T.; Hansen, P.E.

    1997-01-01

    Prediction of 1-octanol water partition coefficients for a range of polar N-PAC from HPLC capacity coefficients has been investigated. Two commercially available columns, an ODS column and a Diol column were tested with water-methanol eluents. The best prediction of log K-ow for N-PAC was achieve...... with size and log K-ow for N-PAC was 1.1-1.3 lower than log K-ow for the equivalent PAH. Shielding of the nitrogen atom in the N-PAC compounds caused an increase in log K-ow. (C) 1997 Elsevier Science Ltd....

  14. Orality and the Archive: Teaching the Partition of India through Oral Histories

    Directory of Open Access Journals (Sweden)

    Gaana Jayagopalan

    2016-07-01

    Full Text Available This article is a reflection on how select oral histories and witness accounts about the partition of India and Pakistan, especially those by Urvashi Butalia and Veena Das were used in a graduate seminar in Bengaluru. The article explores the strength of oral archives as repositories of radical enquiry that may be used in classrooms to understand the complex nature of history, historiography, and interrogate the State’s archival processes. The article explores how students began to see the potency in oral archives as a space that embodies the victimhood of partition victims as opposed to an effacement of the sufferers in most state archives of the event. It observes how the memorialisation of Partition is different in the State’s construction of partition: to the victims who recount their stories, it is the ‘everyday’ that becomes predominant as opposed to State archives that seek to represent the differences between the two nations as paramount in its processes of memorialisation. The note concludes by emphasising the need to put such oral histories to use in classroom, especially to understand the nature of suffering. Through a reading of such stories, it is proposed, an affective literacy is enabled in students’ modes of enquiry about trauma, memory and suffering.   Keywords: Partition of India, affective literacy, archives, oral histories, witness narratives.

  15. Structuring heterogeneous biological information using fuzzy clustering of k-partite graphs

    Directory of Open Access Journals (Sweden)

    Theis Fabian J

    2010-10-01

    Full Text Available Abstract Background Extensive and automated data integration in bioinformatics facilitates the construction of large, complex biological networks. However, the challenge lies in the interpretation of these networks. While most research focuses on the unipartite or bipartite case, we address the more general but common situation of k-partite graphs. These graphs contain k different node types and links are only allowed between nodes of different types. In order to reveal their structural organization and describe the contained information in a more coarse-grained fashion, we ask how to detect clusters within each node type. Results Since entities in biological networks regularly have more than one function and hence participate in more than one cluster, we developed a k-partite graph partitioning algorithm that allows for overlapping (fuzzy clusters. It determines for each node a degree of membership to each cluster. Moreover, the algorithm estimates a weighted k-partite graph that connects the extracted clusters. Our method is fast and efficient, mimicking the multiplicative update rules commonly employed in algorithms for non-negative matrix factorization. It facilitates the decomposition of networks on a chosen scale and therefore allows for analysis and interpretation of structures on various resolution levels. Applying our algorithm to a tripartite disease-gene-protein complex network, we were able to structure this graph on a large scale into clusters that are functionally correlated and biologically meaningful. Locally, smaller clusters enabled reclassification or annotation of the clusters' elements. We exemplified this for the transcription factor MECP2. Conclusions In order to cope with the overwhelming amount of information available from biomedical literature, we need to tackle the challenge of finding structures in large networks with nodes of multiple types. To this end, we presented a novel fuzzy k-partite graph partitioning

  16. PARALLEL PROCESSING OF BIG POINT CLOUDS USING Z-ORDER-BASED PARTITIONING

    Directory of Open Access Journals (Sweden)

    C. Alis

    2016-06-01

    Full Text Available As laser scanning technology improves and costs are coming down, the amount of point cloud data being generated can be prohibitively difficult and expensive to process on a single machine. This data explosion is not only limited to point cloud data. Voluminous amounts of high-dimensionality and quickly accumulating data, collectively known as Big Data, such as those generated by social media, Internet of Things devices and commercial transactions, are becoming more prevalent as well. New computing paradigms and frameworks are being developed to efficiently handle the processing of Big Data, many of which utilize a compute cluster composed of several commodity grade machines to process chunks of data in parallel. A central concept in many of these frameworks is data locality. By its nature, Big Data is large enough that the entire dataset would not fit on the memory and hard drives of a single node hence replicating the entire dataset to each worker node is impractical. The data must then be partitioned across worker nodes in a manner that minimises data transfer across the network. This is a challenge for point cloud data because there exist different ways to partition data and they may require data transfer. We propose a partitioning based on Z-order which is a form of locality-sensitive hashing. The Z-order or Morton code is computed by dividing each dimension to form a grid then interleaving the binary representation of each dimension. For example, the Z-order code for the grid square with coordinates (x = 1 = 012, y = 3 = 112 is 10112 = 11. The number of points in each partition is controlled by the number of bits per dimension: the more bits, the fewer the points. The number of bits per dimension also controls the level of detail with more bits yielding finer partitioning. We present this partitioning method by implementing it on Apache Spark and investigating how different parameters affect the accuracy and running time of the k nearest

  17. The partition coefficients of 133Xe between blood and bone

    International Nuclear Information System (INIS)

    Lahtinen, T.; Karjalainen, P.; Vaeaenaenen, A.; Lahtinen, R.; Alhava, E.M.

    1981-01-01

    The partition coefficients of 133 Xe between blood and haematopoietic bone marrow and homogenised bone have been determined in vitro. The partition coefficient lambda 1 corresponding to haematopoietic marrow was 0.95 ml g -1 while that corresponding to homogenised bone was a function of age, lambda 2 = 3.11 + 0.049(age)(ml g -1 ). These data can be used for calculating regional blood flow in healthy human femur by means of a simple 133 Xe radionuclide method. (author)

  18. Covering sets in R{sup m}

    Energy Technology Data Exchange (ETDEWEB)

    Filimonov, V P [Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow Region (Russian Federation)

    2014-08-31

    The paper investigates questions related to Borsuk's classical problem of partitioningset in Euclidean space into subsets of smaller diameter, as well as to the well-known Nelson-Erdős-Hadwiger problem on the chromatic number of a Euclidean space. The results of the work are obtained using combinatorial and geometric methods alike. A new approach to the investigation of such problems is suggested; it leads to a collection of results which significantly improve all results known so far. Bibliography: 58 titles.

  19. Human Rights and Peace Audit on Partition in South Asia - Phase II ...

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

    3 févr. 2009 ... Human Rights and Peace Audit on Partition in South Asia - Phase II. In South Asia, people's social, political and cultural aspirations often get articulated as movements for territorially defined political change. Very often, these movements find resolution in partition or in an ethnic group/nationality getting ...

  20. Sample size allocation in multiregional equivalence studies.

    Science.gov (United States)

    Liao, Jason J Z; Yu, Ziji; Li, Yulan

    2018-06-17

    With the increasing globalization of drug development, the multiregional clinical trial (MRCT) has gained extensive use. The data from MRCTs could be accepted by regulatory authorities across regions and countries as the primary sources of evidence to support global marketing drug approval simultaneously. The MRCT can speed up patient enrollment and drug approval, and it makes the effective therapies available to patients all over the world simultaneously. However, there are many challenges both operationally and scientifically in conducting a drug development globally. One of many important questions to answer for the design of a multiregional study is how to partition sample size into each individual region. In this paper, two systematic approaches are proposed for the sample size allocation in a multiregional equivalence trial. A numerical evaluation and a biosimilar trial are used to illustrate the characteristics of the proposed approaches. Copyright © 2018 John Wiley & Sons, Ltd.