WorldWideScience

Sample records for order-k delineable problems

  1. Sequential versus simultaneous market delineation

    DEFF Research Database (Denmark)

    Haldrup, Niels; Møllgaard, Peter; Kastberg Nielsen, Claus

    2005-01-01

    and geographical markets. Using a unique data setfor prices of Norwegian and Scottish salmon, we propose a methodologyfor simultaneous market delineation and we demonstrate that comparedto a sequential approach conclusions will be reversed.JEL: C3, K21, L41, Q22Keywords: Relevant market, econometric delineation......Delineation of the relevant market forms a pivotal part of most antitrustcases. The standard approach is sequential. First the product marketis delineated, then the geographical market is defined. Demand andsupply substitution in both the product dimension and the geographicaldimension...

  2. The aligned K-center problem

    KAUST Repository

    Braß, Peter

    2011-04-01

    In this paper we study several instances of the aligned k-center problem where the goal is, given a set of points S in the plane and a parameter k ≥ 1, to find k disks with centers on a line ℓ such that their union covers S and the maximum radius of the disks is minimized. This problem is a constrained version of the well-known k-center problem in which the centers are constrained to lie in a particular region such as a segment, a line, or a polygon. We first consider the simplest version of the problem where the line ℓ is given in advance; we can solve this problem in time O(n log2 n). In the case where only the direction of ℓ is fixed, we give an O(n2 log 2 n)-time algorithm. When ℓ is an arbitrary line, we give a randomized algorithm with expected running time O(n4 log2 n). Then we present (1+ε)-approximation algorithms for these three problems. When we denote T(k, ε) = (k/ε2+(k/ε) log k) log(1/ε), these algorithms run in O(n log k + T(k, ε)) time, O(n log k + T(k, ε)/ε) time, and O(n log k + T(k, ε)/ε2) time, respectively. For k = O(n1/3/log n), we also give randomized algorithms with expected running times O(n + (k/ε2) log(1/ε)), O(n+(k/ε3) log(1/ε)), and O(n + (k/ε4) log(1/ε)), respectively. © 2011 World Scientific Publishing Company.

  3. Transit Traffic Analysis Zone Delineating Method Based on Thiessen Polygon

    Directory of Open Access Journals (Sweden)

    Shuwei Wang

    2014-04-01

    Full Text Available A green transportation system composed of transit, busses and bicycles could be a significant in alleviating traffic congestion. However, the inaccuracy of current transit ridership forecasting methods is imposing a negative impact on the development of urban transit systems. Traffic Analysis Zone (TAZ delineating is a fundamental and essential step in ridership forecasting, existing delineating method in four-step models have some problems in reflecting the travel characteristics of urban transit. This paper aims to come up with a Transit Traffic Analysis Zone delineation method as supplement of traditional TAZs in transit service analysis. The deficiencies of current TAZ delineating methods were analyzed, and the requirements of Transit Traffic Analysis Zone (TTAZ were summarized. Considering these requirements, Thiessen Polygon was introduced into TTAZ delineating. In order to validate its feasibility, Beijing was then taken as an example to delineate TTAZs, followed by a spatial analysis of office buildings within a TTAZ and transit station departure passengers. Analysis result shows that the TTAZs based on Thiessen polygon could reflect the transit travel characteristic and is of in-depth research value.

  4. Ordered and Unordered Top-K Range Reporting in Large Data Sets

    DEFF Research Database (Denmark)

    Afshani, Peyman; Brodal, Gerth Stølting; Zeh, Norbert

    2011-01-01

    We study the following problem: Given an array A storing N real numbers, preprocess it to allow fast reporting of the K smallest elements in the subarray A[i, j] in sorted order, for any triple (i, j,K) with 1 ≤ i ≤ j ≤ N and 1 ≤ K ≤ j − i + 1. We are interested in scenarios where the array A is ...

  5. Adaptive sampling based on the cumulative distribution function of order statistics to delineate heavy-metal contaminated soils using kriging

    International Nuclear Information System (INIS)

    Juang, K.-W.; Lee, D.-Y.; Teng, Y.-L.

    2005-01-01

    Correctly classifying 'contaminated' areas in soils, based on the threshold for a contaminated site, is important for determining effective clean-up actions. Pollutant mapping by means of kriging is increasingly being used for the delineation of contaminated soils. However, those areas where the kriged pollutant concentrations are close to the threshold have a high possibility for being misclassified. In order to reduce the misclassification due to the over- or under-estimation from kriging, an adaptive sampling using the cumulative distribution function of order statistics (CDFOS) was developed to draw additional samples for delineating contaminated soils, while kriging. A heavy-metal contaminated site in Hsinchu, Taiwan was used to illustrate this approach. The results showed that compared with random sampling, adaptive sampling using CDFOS reduced the kriging estimation errors and misclassification rates, and thus would appear to be a better choice than random sampling, as additional sampling is required for delineating the 'contaminated' areas. - A sampling approach was derived for drawing additional samples while kriging

  6. Efficient solutions to the NDA-NCA low-order eigenvalue problem

    International Nuclear Information System (INIS)

    Willert, J. A.; Kelley, C. T.

    2013-01-01

    Recent algorithmic advances combine moment-based acceleration and Jacobian-Free Newton-Krylov (JFNK) methods to accelerate the computation of the dominant eigenvalue in a k-eigenvalue calculation. In particular, NDA-NCA [1], builds a sequence of low-order (LO) diffusion-based eigenvalue problems in which the solution converges to the true eigenvalue solution. Within NDA-NCA, the solution to the LO k-eigenvalue problem is computed by solving a system of nonlinear equation using some variant of Newton's method. We show that we can speed up the solution to the LO problem dramatically by abandoning the JFNK method and exploiting the structure of the Jacobian matrix. (authors)

  7. Warehouse order-picking process. Order-picker routing problem

    Directory of Open Access Journals (Sweden)

    E. V. Korobkov

    2015-01-01

    Full Text Available This article continues “Warehouse order-picking process” cycle and describes order-picker routing sub-problem of a warehouse order-picking process. It draws analogies between the orderpickers’ routing problem and traveling salesman’s problem, shows differences between the standard problem statement of a traveling salesman and routing problem of warehouse orderpickers, and gives the particular Steiner’s problem statement of a traveling salesman.Warehouse layout with a typical order is represented by a graph, with some its vertices corresponding to mandatory order-picker’s visits and some other ones being noncompulsory. The paper describes an optimal Ratliff-Rosenthal algorithm to solve order-picker’s routing problem for the single-block warehouses, i.e. warehouses with only two crossing aisles, defines seven equivalent classes of partial routing sub-graphs and five transitions used to have an optimal routing sub-graph of a order-picker. An extension of optimal Ratliff-Rosenthal order-picker routing algorithm for multi-block warehouses is presented and also reasons for using the routing heuristics instead of exact optimal algorithms are given. The paper offers algorithmic description of the following seven routing heuristics: S-shaped, return, midpoint, largest gap, aisle-by-aisle, composite, and combined as well as modification of combined heuristics. The comparison of orderpicker routing heuristics for one- and two-block warehouses is to be described in the next article of the “Warehouse order-picking process” cycle.

  8. The aligned K-center problem

    KAUST Repository

    Braß , Peter; Knauer, Christian; Na, Hyeonsuk; Shin, Chansu; Vigneron, Antoine E.

    2011-01-01

    running time O(n4 log2 n). Then we present (1+ε)-approximation algorithms for these three problems. When we denote T(k, ε) = (k/ε2+(k/ε) log k) log(1/ε), these algorithms run in O(n log k + T(k, ε)) time, O(n log k + T(k, ε)/ε) time, and O(n log k + T(k, ε

  9. Randomized and quantum algorithms for solving initial-value problems in ordinary differential equations of order k

    Directory of Open Access Journals (Sweden)

    Maciej Goćwin

    2008-01-01

    Full Text Available The complexity of initial-value problems is well studied for systems of equations of first order. In this paper, we study the \\(\\varepsilon\\-complexity for initial-value problems for scalar equations of higher order. We consider two models of computation, the randomized model and the quantum model. We construct almost optimal algorithms adjusted to scalar equations of higher order, without passing to systems of first order equations. The analysis of these algorithms allows us to establish upper complexity bounds. We also show (almost matching lower complexity bounds. The \\(\\varepsilon\\-complexity in the randomized and quantum setting depends on the regularity of the right-hand side function, but is independent of the order of equation. Comparing the obtained bounds with results known in the deterministic case, we see that randomized algorithms give us a speed-up by \\(1/2\\, and quantum algorithms by \\(1\\ in the exponent. Hence, the speed-up does not depend on the order of equation, and is the same as for the systems of equations of first order. We also include results of some numerical experiments which confirm theoretical results.

  10. A Dynamic Programming Algorithm for the k-Haplotyping Problem

    Institute of Scientific and Technical Information of China (English)

    Zhen-ping Li; Ling-yun Wu; Yu-ying Zhao; Xiang-sun Zhang

    2006-01-01

    The Minimum Fragments Removal (MFR) problem is one of the haplotyping problems: given a set of fragments, remove the minimum number of fragments so that the resulting fragments can be partitioned into k classes of non-conflicting subsets. In this paper, we formulate the k-MFR problem as an integer linear programming problem, and develop a dynamic programming approach to solve the k-MFR problem for both the gapless and gap cases.

  11. Higher-Order Generalized Invexity in Control Problems

    Directory of Open Access Journals (Sweden)

    S. K. Padhan

    2011-01-01

    Full Text Available We introduce a higher-order duality (Mangasarian type and Mond-Weir type for the control problem. Under the higher-order generalized invexity assumptions on the functions that compose the primal problems, higher-order duality results (weak duality, strong duality, and converse duality are derived for these pair of problems. Also, we establish few examples in support of our investigation.

  12. Recent advances in probabilistic species pool delineations

    Directory of Open Access Journals (Sweden)

    Dirk Nikolaus Karger

    2016-07-01

    Full Text Available A species pool is the set of species that could potentially colonize and establish within a community. It has been a commonly used concept in biogeography since the early days of MacArthur and Wilson’s work on Island Biogeography. Despite their simple and appealing definition, an operational application of species pools is bundled with a multitude of problems, which have often resulted in arbitrary decisions and workarounds when defining species pools. Two recently published papers address the operational problems of species pool delineations, and show ways of delineating them in a probabilistic fashion. In both papers, species pools were delineated using a process-based, mechanistical approach, which opens the door for a multitude of new applications in biogeography. Such applications include detecting the hidden signature of biotic interactions, disentangling the geographical structure of community assembly processes, and incorporating a temporal extent into species pools. Although similar in their conclusions, both ‘probabilistic approaches’ differ in their implementation and definitions. Here I give a brief overview of the differences and similarities of both approaches, and identify the challenges and advantages in their application.

  13. Metal artefact reduction for accurate tumour delineation in radiotherapy

    DEFF Research Database (Denmark)

    Kovacs, David Gergely; Rechner, Laura A.; Appelt, Ane L.

    2018-01-01

    Background and purpose: Two techniques for metal artefact reduction for computed tomography were studied in order to identify their impact on tumour delineation in radiotherapy. Materials and methods: Using specially designed phantoms containing metal implants (dental, spine and hip) as well...... delineation significantly (pmetal implant....... as patient images, we investigated the impact of two methods for metal artefact reduction on (A) the size and severity of metal artefacts and the accuracy of Hounsfield Unit (HU) representation, (B) the visual impact of metal artefacts on image quality and (C) delineation accuracy. A metal artefact reduction...

  14. K-chameleon and the coincidence problem

    International Nuclear Information System (INIS)

    Wei Hao; Cai Ronggen

    2005-01-01

    In this paper we present a hybrid model of k-essence and chameleon, named as k-chameleon. In this model, due to the chameleon mechanism, the directly strong coupling between the k-chameleon field and matters (cold dark matters and baryons) is allowed. In the radiation-dominated epoch, the interaction between the k-chameleon field and background matters can be neglected; the behavior of the k-chameleon therefore is the same as that of the ordinary k-essence. After the onset of matter domination, the strong coupling between the k-chameleon and matters dramatically changes the result of the ordinary k-essence. We find that during the matter-dominated epoch, only two kinds of attractors may exist: one is the familiar K attractor and the other is a completely new, dubbed C attractor. Once the Universe is attracted into the C attractor, the fraction energy densities of the k-chameleon Ω φ and dust matter Ω m are fixed and comparable, and the Universe will undergo a power-law accelerated expansion. One can adjust the model so that the K attractor does not appear. Thus, the k-chameleon model provides a natural solution to the cosmological coincidence problem

  15. A Linear Time Algorithm for the k Maximal Sums Problem

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Jørgensen, Allan Grønlund

    2007-01-01

     k maximal sums problem. We use this algorithm to obtain algorithms solving the two-dimensional k maximal sums problem in O(m 2·n + k) time, where the input is an m ×n matrix with m ≤ n. We generalize this algorithm to solve the d-dimensional problem in O(n 2d − 1 + k) time. The space usage of all......Finding the sub-vector with the largest sum in a sequence of n numbers is known as the maximum sum problem. Finding the k sub-vectors with the largest sums is a natural extension of this, and is known as the k maximal sums problem. In this paper we design an optimal O(n + k) time algorithm for the...... the algorithms can be reduced to O(n d − 1 + k). This leads to the first algorithm for the k maximal sums problem in one dimension using O(n + k) time and O(k) space....

  16. Solving k-Barrier Coverage Problem Using Modified Gravitational Search Algorithm

    Directory of Open Access Journals (Sweden)

    Yanhua Zhang

    2017-01-01

    Full Text Available Coverage problem is a critical issue in wireless sensor networks for security applications. The k-barrier coverage is an effective measure to ensure robustness. In this paper, we formulate the k-barrier coverage problem as a constrained optimization problem and introduce the energy constraint of sensor node to prolong the lifetime of the k-barrier coverage. A novel hybrid particle swarm optimization and gravitational search algorithm (PGSA is proposed to solve this problem. The proposed PGSA adopts a k-barrier coverage generation strategy based on probability and integrates the exploitation ability in particle swarm optimization to update the velocity and enhance the global search capability and introduce the boundary mutation strategy of an agent to increase the population diversity and search accuracy. Extensive simulations are conducted to demonstrate the effectiveness of our proposed algorithm.

  17. ANALYTICAL SOLUTION OF THE K-TH ORDER AUTONOMOUS ORDINARY DIFFERENTIAL EQUATION

    Directory of Open Access Journals (Sweden)

    Ronald Orozco López

    2017-04-01

    Full Text Available The main objective of this paper is to find the analytical solution of the autonomous equation y(k = f (y and prove its convergence using autonomous polynomials of order k, define here in addition of the formula of Faá di Bruno for composition of functions and Bell polynomials. Autonomous polynomials of order k are defined in terms of the boundary values of the equation. Also special values of autonomous polynomials of order 1 are given.

  18. Multimodality Tumor Delineation and Predictive Modelling via Fuzzy-Fusion Deformable Models and Biological Potential Functions

    Science.gov (United States)

    Wasserman, Richard Marc

    The radiation therapy treatment planning (RTTP) process may be subdivided into three planning stages: gross tumor delineation, clinical target delineation, and modality dependent target definition. The research presented will focus on the first two planning tasks. A gross tumor target delineation methodology is proposed which focuses on the integration of MRI, CT, and PET imaging data towards the generation of a mathematically optimal tumor boundary. The solution to this problem is formulated within a framework integrating concepts from the fields of deformable modelling, region growing, fuzzy logic, and data fusion. The resulting fuzzy fusion algorithm can integrate both edge and region information from multiple medical modalities to delineate optimal regions of pathological tissue content. The subclinical boundaries of an infiltrating neoplasm cannot be determined explicitly via traditional imaging methods and are often defined to extend a fixed distance from the gross tumor boundary. In order to improve the clinical target definition process an estimation technique is proposed via which tumor growth may be modelled and subclinical growth predicted. An in vivo, macroscopic primary brain tumor growth model is presented, which may be fit to each patient undergoing treatment, allowing for the prediction of future growth and consequently the ability to estimate subclinical local invasion. Additionally, the patient specific in vivo tumor model will be of significant utility in multiple diagnostic clinical applications.

  19. (AJST) THE LINEAR ORDERING PROBLEM: AN ALGORITHM FOR ...

    African Journals Online (AJOL)

    ABSTRACT:- In this paper we describe and implement an algorithm for the exact ... of the solutions space which grows exponentially with ... terms of the formulation of the problem, these are the ... Definition: A digraph D = (V, A) is called a k-fence if it has the following ... (iv) If two dicycles Ci and Cj, 2k have a node,.

  20. Delineation of Rain Areas with TRMM Microwave Observations Based on PNN

    Directory of Open Access Journals (Sweden)

    Shiguang Xu

    2014-12-01

    Full Text Available False alarm and misdetected precipitation are prominent drawbacks of high-resolution satellite precipitation datasets, and they usually lead to serious uncertainty in hydrological and meteorological applications. In order to provide accurate rain area delineation for retrieving high-resolution precipitation datasets using satellite microwave observations, a probabilistic neural network (PNN-based rain area delineation method was developed with rain gauge observations over the Yangtze River Basin and three parameters, including polarization corrected temperature at 85 GHz, difference of brightness temperature at vertically polarized 37 and 19 GHz channels (termed as TB37V and TB19V, respectively and the sum of TB37V and TB19V derived from the observations of the Tropical Rainfall Measuring Mission (TRMM Microwave Imager (TMI. The PNN method was validated with independent samples, and the performance of this method was compared with dynamic cluster K-means method, TRMM Microwave Imager (TMI Level 2 Hydrometeor Profile Product and the threshold method used in the Scatter Index (SI, a widely used microwave-based precipitation retrieval algorithm. Independent validation indicated that the PNN method can provide more reasonable rain areas than the other three methods. Furthermore, the precipitation volumes estimated by the SI algorithm were significantly improved by substituting the PNN method for the threshold method in the traditional SI algorithm. This study suggests that PNN is a promising way to obtain reasonable rain areas with satellite observations, and the development of an accurate rain area delineation method deserves more attention for improving the accuracy of satellite precipitation datasets.

  1. Nicolaides-Baraitser Syndrome: Delineation of the Phenotype

    NARCIS (Netherlands)

    Sousa, Sérgio B.; Abdul-Rahman, Omar A.; Bottani, Armand; Cormier-Daire, Valérie; Fryer, Alan; Gillessen-Kaesbach, Gabriele; Horn, Denise; Josifova, Dragana; Kuechler, Alma; Lees, Melissa; Macdermot, Kay; Magee, Alex; Morice-Picard, Fanny; Rosser, Elizabeth; Sarkar, Ajoy; Shannon, Nora; Stolte-Dijkstra, Irene; Verloes, Alain; Wakeling, Emma; Wilson, Louise; Hennekam, Raoul C. M.

    2009-01-01

    Nicolaides-Baraitser syndrome (NBS) is an infrequently described condition, thus far reported in five cases. In order to delineate the phenotype and its natural history in more detail, we gathered data on 18 hitherto unreported patients through a multi-center collaborative study, and follow-up data

  2. Nicolaides-Baraitser Syndrome : Delineation of the Phenotype

    NARCIS (Netherlands)

    Sousa, Sergio B.; Abdul-Rahman, Omar A.; Bottani, Armand; Cormier-Daire, Valerie; Fryer, Alan; Gillessen-Kaesbach, Gabriele; Horn, Denise; Josifova, Dragana; Kuechler, Alma; Lees, Melissa; MacDermot, Kay; Magee, Alex; Morice-Picard, Fanny; Rosser, Elizabeth; Sarkar, Ajoy; Shannon, Nora; Stolte-Dijkstra, Irene; Verloes, Alain; Wakeling, Emma; Wilson, Louise; Hennekam, Raoul C. M.

    Nicolaides-Baraitser syndrome (NBS) is an infrequently described condition, thus far reported in five cases. In order to delineate the phenotype and its natural history in more detail, we gathered data on 18 hitherto unreported patients through a multi-center collaborative study, and follow-up data

  3. Fuzzy Kernel k-Medoids algorithm for anomaly detection problems

    Science.gov (United States)

    Rustam, Z.; Talita, A. S.

    2017-07-01

    Intrusion Detection System (IDS) is an essential part of security systems to strengthen the security of information systems. IDS can be used to detect the abuse by intruders who try to get into the network system in order to access and utilize the available data sources in the system. There are two approaches of IDS, Misuse Detection and Anomaly Detection (behavior-based intrusion detection). Fuzzy clustering-based methods have been widely used to solve Anomaly Detection problems. Other than using fuzzy membership concept to determine the object to a cluster, other approaches as in combining fuzzy and possibilistic membership or feature-weighted based methods are also used. We propose Fuzzy Kernel k-Medoids that combining fuzzy and possibilistic membership as a powerful method to solve anomaly detection problem since on numerical experiment it is able to classify IDS benchmark data into five different classes simultaneously. We classify IDS benchmark data KDDCup'99 data set into five different classes simultaneously with the best performance was achieved by using 30 % of training data with clustering accuracy reached 90.28 percent.

  4. Quantum algorithms for the ordered search problem via semidefinite programming

    International Nuclear Information System (INIS)

    Childs, Andrew M.; Landahl, Andrew J.; Parrilo, Pablo A.

    2007-01-01

    One of the most basic computational problems is the task of finding a desired item in an ordered list of N items. While the best classical algorithm for this problem uses log 2 N queries to the list, a quantum computer can solve the problem using a constant factor fewer queries. However, the precise value of this constant is unknown. By characterizing a class of quantum query algorithms for the ordered search problem in terms of a semidefinite program, we find quantum algorithms for small instances of the ordered search problem. Extending these algorithms to arbitrarily large instances using recursion, we show that there is an exact quantum ordered search algorithm using 4 log 605 N≅0.433 log 2 N queries, which improves upon the previously best known exact algorithm

  5. Aspen Delineation - Aspen Delineation Project [ds362

    Data.gov (United States)

    California Natural Resource Agency — The database represents delineations of aspen stands, where aspen assessment data was gathered. Aspen assessment information corresponding to this polygon layer can...

  6. K-State Problem Identification Rating Scales for College Students

    Science.gov (United States)

    Robertson, John M.; Benton, Stephen L.; Newton, Fred B.; Downey, Ronald G.; Marsh, Patricia A.; Benton, Sheryl A.; Tseng, Wen-Chih; Shin, Kang-Hyun

    2006-01-01

    The K-State Problem Identification Rating Scales, a new screening instrument for college counseling centers, gathers information about clients' presenting symptoms, functioning levels, and readiness to change. Three studies revealed 7 scales: Mood Difficulties, Learning Problems, Food Concerns, Interpersonal Conflicts, Career Uncertainties,…

  7. Higher-order techniques for some problems of nonlinear control

    Directory of Open Access Journals (Sweden)

    Sarychev Andrey V.

    2002-01-01

    Full Text Available A natural first step when dealing with a nonlinear problem is an application of some version of linearization principle. This includes the well known linearization principles for controllability, observability and stability and also first-order optimality conditions such as Lagrange multipliers rule or Pontryagin's maximum principle. In many interesting and important problems of nonlinear control the linearization principle fails to provide a solution. In the present paper we provide some examples of how higher-order methods of differential geometric control theory can be used for the study nonlinear control systems in such cases. The presentation includes: nonlinear systems with impulsive and distribution-like inputs; second-order optimality conditions for bang–bang extremals of optimal control problems; methods of high-order averaging for studying stability and stabilization of time-variant control systems.

  8. The linear ordering problem: an algorithm for the optimal solution ...

    African Journals Online (AJOL)

    In this paper we describe and implement an algorithm for the exact solution of the Linear Ordering problem. Linear Ordering is the problem of finding a linear order of the nodes of a graph such that the sum of the weights which are consistent with this order is as large as possible. It is an NP - Hard combinatorial optimisation ...

  9. Ordering alternatives in MCDM problems

    International Nuclear Information System (INIS)

    De Baets, B.

    1994-01-01

    A new approach to the study of a set of alternatives in a multi-criteria decision making problem is presented. Alternatives are described by means of fuzzy sets in the set of criteria, expressing the degrees to which they fulfill the different criteria. The concept of a fuzzy inclusion is introduced and is discussed from an axiomatic point of view. To each implication operator corresponds a fuzzy inclusion. The fuzzy inclusion corresponding to the Goedel operator is used to measure the degree to which the scores of one alternative are contained in the scores of another one. Repeating this for all couples of alternatives yields a fuzzy quasi-order relation in a set of alternatives. The cuts of this fuzzy relation are then classical quasi-order relations: they express orderings of the alternatives, allowing alternatives to be indifferent or incomparable, corresponding to different degrees of confidence

  10. 30 CFR 282.22 - Delineation Plan.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Delineation Plan. 282.22 Section 282.22 Mineral... § 282.22 Delineation Plan. All exploration activities shall be conducted in accordance with a Delineation Plan submitted by the lessee and approved by the Director. The Delineation Plan shall describe the...

  11. A polylogarithmic competitive algorithm for the k-server problem

    NARCIS (Netherlands)

    Bansal, N.; Buchbinder, N.; Madry, A.; Naor, J.

    2011-01-01

    We give the first polylogarithmic-competitive randomized online algorithm for the $k$-server problem on an arbitrary finite metric space. In particular, our algorithm achieves a competitive ratio of O(log^3 n log^2 k log log n) for any metric space on n points. Our algorithm improves upon the

  12. Delineating psychomotor slowing from reduced processing speed in schizophrenia

    NARCIS (Netherlands)

    Morrens, M.; Hulstijn, W.; Matton, C.; Madani, Y.; Bouwel, L. van; Peuskens, J.; Sabbe, B.G.C.

    2008-01-01

    Introduction. Psychomotor slowing is an intrinsic feature of schizophrenia that is poorly delineated from generally reduced processing speed. Although the Symbol Digit Substitution Test (SDST) is widely used to assess psychomotor speed, the task also taps several higher-order cognitive processes.

  13. Myanmar and Y2K problem

    International Nuclear Information System (INIS)

    Kyaw Zwa Soe

    1999-01-01

    Government of Myanmar set up a national committee for steering to overcome the Y2K problem smoothly. The responsibility of this committee is: to survey the governmental and private organizations using the computers or computer controlled machines; to identify whether they are compliant to year 2000 and to give information on the subject to the public through the media. Identification and certification are to be carried out as well

  14. delineating the jurassic to mid-cretaceous part of the pacific ...

    African Journals Online (AJOL)

    Mgina

    paleomagnetic field. This problem was solved by the formulation of the seamount paleomagnetism technique (Talwani 1965,. Plouff 1976, Parker et al. 1987). Following this, Sager and Pringle (1988) using mainly seamount paleomagnetic data delineated a well defined Pacific ... earth's surface and abuts six major and.

  15. The Noether-Lefschetz problem and gauge-group-resolved landscapes: F-theory on K3 × K3 as a test case

    Energy Technology Data Exchange (ETDEWEB)

    Braun, A.P. [Department of Mathematics, King’s College,London WC2R 2LS (United Kingdom); Kimura, Y. [Yukawa Institute for Theoretical Physics, Kyoto University,Kyoto 606-8502 (Japan); Watari, T. [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo,Kashiwano-ha 5-1-5, 277-8583 (Japan)

    2014-04-07

    Four-form flux in F-theory compactifications not only stabilizes moduli, but gives rise to ensembles of string vacua, providing a scientific basis for a stringy notion of naturalness. Of particular interest in this context is the ability to keep track of algebraic information (such as the gauge group) associated with individual vacua while dealing with statistics. In the present work, we aim to clarify conceptual issues and sharpen methods for this purpose, using compactification on KK3 as a test case. Our first approach exploits the connection between the stabilization of complex structure moduli and the Noether-Lefschetz problem. Compactification data for F-theory, however, involve not only a four-fold (with a given complex structure) Y{sub 4} and a flux on it, but also an elliptic fibration morphism Y{sub 4}⟶B{sub 3}, which makes this problem complicated. The heterotic-F-theory duality indicates that elliptic fibration morphisms should be identified modulo isomorphism. Based on this principle, we explain how to count F-theory vacua on KK3 while keeping the gauge group information. Mathematical results reviewed/developed in our companion paper are exploited heavily. With applications to more general four-folds in mind, we also clarify how to use Ashok-Denef-Douglas’ theory of the distribution of flux vacua in order to deal with statistics of sub-ensembles tagged by a given set of algebraic/topological information. As a side remark, we extend the heterotic/F-theory duality dictionary on flux quanta and elaborate on its connection to the semistable degeneration of a K3 surface.

  16. Ordering schemes for parallel processing of certain mesh problems

    International Nuclear Information System (INIS)

    O'Leary, D.

    1984-01-01

    In this work, some ordering schemes for mesh points are presented which enable algorithms such as the Gauss-Seidel or SOR iteration to be performed efficiently for the nine-point operator finite difference method on computers consisting of a two-dimensional grid of processors. Convergence results are presented for the discretization of u /SUB xx/ + u /SUB yy/ on a uniform mesh over a square, showing that the spectral radius of the iteration for these orderings is no worse than that for the standard row by row ordering of mesh points. Further applications of these mesh point orderings to network problems, more general finite difference operators, and picture processing problems are noted

  17. A procrastinator's guide to the Y2K problem.

    Science.gov (United States)

    Deveau, A G

    1999-01-01

    Your workplace has undoubtedly spent a great deal of time and money over the past few years on the Year 2000 (Y2K) problem. The focus of this article, however, is not on Y2K in the health care industry. Frankly, if your organization is not ready by now, it's too late. Your home computer, however, may be another story.

  18. Nonlinear singular perturbation problems of arbitrary real orders

    International Nuclear Information System (INIS)

    Bijura, Angelina M.

    2003-10-01

    Higher order asymptotic solutions of singularly perturbed nonlinear fractional integral and derivatives of order 1/2 are investigated. It is particularly shown that whilst certain asymptotic expansions are applied successfully to linear equations and particular nonlinear problems, the standard formal asymptotic expansion is appropriate for the general class of nonlinear equations. This theory is then generalised to the general equation (of order β, 0 < β < 1). (author)

  19. On the complexity of the balanced vertex ordering problem

    Directory of Open Access Journals (Sweden)

    Jan Kara

    2007-01-01

    Full Text Available We consider the problem of finding a balanced ordering of the vertices of a graph. More precisely, we want to minimise the sum, taken over all vertices v, of the difference between the number of neighbours to the left and right of v. This problem, which has applications in graph drawing, was recently introduced by Biedl et al. [Discrete Applied Math. 148:27--48, 2005]. They proved that the problem is solvable in polynomial time for graphs with maximum degree three, but NP-hard for graphs with maximum degree six. One of our main results is to close the gap in these results, by proving NP-hardness for graphs with maximum degree four. Furthermore, we prove that the problem remains NP-hard for planar graphs with maximum degree four and for 5-regular graphs. On the other hand, we introduce a polynomial time algorithm that determines whetherthere is a vertex ordering with total imbalance smaller than a fixed constant, and a polynomial time algorithm that determines whether a given multigraph with even degrees has an `almost balanced' ordering.

  20. Phase diagram and quantum order by disorder in the Kitaev K1-K2 honeycomb magnet

    Science.gov (United States)

    Rousochatzakis, Ioannis; Reuther, Johannes; Thomale, Ronny; Rachel, Stephan; Perkins, Natalia

    We show that the topological Kitaev spin liquid on the honeycomb lattice is extremely fragile against the second neighbor Kitaev coupling K2, which has been recently identified as the dominant perturbation away from the nearest neighbor model in iridate Na2IrO3, and may also play a role in α-RuCl3. This coupling explains naturally the zig-zag ordering and the special entanglement between real and spin space observed recently in Na2IrO3. The minimal K1-K2 model that we present here holds in addition the unique property that the classical and quantum phase diagrams and their respective order-by-disorder mechanisms are qualitatively different due to their fundamentally different symmetry structure. Nsf DMR-1511768; Freie Univ. Berlin Excellence Initiative of German Research Foundation; European Research Council, ERC-StG-336012; DFG-SFB 1170; DFG-SFB 1143, DFG-SPP 1666, and Helmholtz association VI-521.

  1. Two- and three-index formulations of the minimum cost multicommodity k-splittable flow problem

    DEFF Research Database (Denmark)

    Gamst, Mette; Jensen, Peter Neergaard; Pisinger, David

    2010-01-01

    The multicommodity flow problem (MCFP) considers the efficient routing of commodities from their origins to their destinations subject to capacity restrictions and edge costs. Baier et al. [G. Baier, E. Köhler, M. Skutella, On the k-splittable flow problem, in: 10th Annual European Symposium...... of commodities has to be satisfied at the lowest possible cost. The problem has applications in transportation problems where a number of commodities must be routed, using a limited number of distinct transportation units for each commodity. Based on a three-index formulation by Truffot et al. [J. Truffot, C...... on Algorithms, 2002, 101–113] introduced the maximum flow multicommodity k-splittable flow problem (MCkFP) where each commodity may use at most k paths between its origin and its destination. This paper studies the -hard minimum cost multicommodity k-splittable flow problem (MCMCkFP) in which a given flow...

  2. New Y2K problem for mask making (or, Surviving mask data problems after 2000)

    Science.gov (United States)

    Sturgeon, Roger

    1999-08-01

    The Y2K problem has analogies in the mask-making world. With the Y2K problem where a date field has just two bytes for the year, there are some cases of mask-making data in which the file size cannot exceed 2 gigabytes. Where a two-digit date field can only unambiguously use a limited range of values (00 to 99), design coordinates can only cover a range of about 4 billion values, which is getting a little uncomfortable for all of the new applications. In retrospect, with a degree of foresight and planning the Y2K date problem could have been easily solved if new encodings had been allowed in the two- digit field. Likewise, in the mask-making industry we currently have the opportunity to achieve far superior data compression if we allow some new forms of data encoding in our data. But this will require universal agreement. The correct way to look at the Y2K problem is that some information was left out of the data stream due to common understandings that made the additional information superfluous. But as the year 2000 approaches, it has become widely recognized that missing data needs to be stated explicitly, and any ambiguities in the representation of the data will need to be eliminated with precise specifications. In a similar way, old mask data generation methods have had numerous flaws that we have been able to ignore for a long time. But now is the time to fix theses flaws and provide extended capabilities. What is not yet clear is if the old data generation methods can be modified to meet these developing needs. Unilateral action is not likely to lead to much progress, so some united effort is required by all interested parties if success is to be achieved in the brief time that remains.

  3. The Cauchy problem for higher order abstract differential equations

    CERN Document Server

    Xiao, Ti-Jun

    1998-01-01

    This monograph is the first systematic exposition of the theory of the Cauchy problem for higher order abstract linear differential equations, which covers all the main aspects of the developed theory. The main results are complete with detailed proofs and established recently, containing the corresponding theorems for first and incomplete second order cases and therefore for operator semigroups and cosine functions. They will find applications in many fields. The special power of treating the higher order problems directly is demonstrated, as well as that of the vector-valued Laplace transforms in dealing with operator differential equations and operator families. The reader is expected to have a knowledge of complex and functional analysis.

  4. Delineation, characterization, and classification of topographic eminences

    Science.gov (United States)

    Sinha, Gaurav

    Topographic eminences are defined as upwardly rising, convex shaped topographic landforms that are noticeably distinct in their immediate surroundings. As opposed to everyday objects, the properties of a topographic eminence are dependent not only on how it is conceptualized, but is also intrinsically related to its spatial extent and its relative location in the landscape. In this thesis, a system for automated detection, delineation and characterization of topographic eminences based on an analysis of digital elevation models is proposed. Research has shown that conceptualization of eminences (and other landforms) is linked to the cultural and linguistic backgrounds of people. However, the perception of stimuli from our physical environment is not subject to cultural or linguistic bias. Hence, perceptually salient morphological and spatial properties of the natural landscape can form the basis for generically applicable detection and delineation of topographic eminences. Six principles of cognitive eminence modeling are introduced to develop the philosophical foundation of this research regarding eminence delineation and characterization. The first step in delineating eminences is to automatically detect their presence within digital elevation models. This is achieved by the use of quantitative geomorphometric parameters (e.g., elevation, slope and curvature) and qualitative geomorphometric features (e.g., peaks, passes, pits, ridgelines, and valley lines). The process of eminence delineation follows that of eminence detection. It is posited that eminences may be perceived either as monolithic terrain objects, or as composites of morphological parts (e.g., top, bottom, slope). Individual eminences may also simultaneously be conceived as comprising larger, higher order eminence complexes (e.g., mountain ranges). Multiple algorithms are presented for the delineation of simple and complex eminences, and the morphological parts of eminences. The proposed eminence

  5. Problem-Based Learning in the Physical Science Classroom, K-12

    Science.gov (United States)

    McConnell, Tom J.; Parker, Joyce; Eberhardt, Janet

    2018-01-01

    "Problem-Based Learning in the Physical Science Classroom, K-12" will help your students truly understand concepts such as motion, energy, and magnetism in true-to-life contexts. The book offers a comprehensive description of why, how, and when to implement problem-based learning (PBL) in your curriculum. Its 14 developmentally…

  6. Radiotherapy volume delineation using dynamic [18F]-FDG PET/CT imaging in patients with oropharyngeal cancer: a pilot study.

    Science.gov (United States)

    Silvoniemi, Antti; Din, Mueez U; Suilamo, Sami; Shepherd, Tony; Minn, Heikki

    2016-11-01

    Delineation of gross tumour volume in 3D is a critical step in the radiotherapy (RT) treatment planning for oropharyngeal cancer (OPC). Static [ 18 F]-FDG PET/CT imaging has been suggested as a method to improve the reproducibility of tumour delineation, but it suffers from low specificity. We undertook this pilot study in which dynamic features in time-activity curves (TACs) of [ 18 F]-FDG PET/CT images were applied to help the discrimination of tumour from inflammation and adjacent normal tissue. Five patients with OPC underwent dynamic [ 18 F]-FDG PET/CT imaging in treatment position. Voxel-by-voxel analysis was performed to evaluate seven dynamic features developed with the knowledge of differences in glucose metabolism in different tissue types and visual inspection of TACs. The Gaussian mixture model and K-means algorithms were used to evaluate the performance of the dynamic features in discriminating tumour voxels compared to the performance of standardized uptake values obtained from static imaging. Some dynamic features showed a trend towards discrimination of different metabolic areas but lack of consistency means that clinical application is not recommended based on these results alone. Impact of inflammatory tissue remains a problem for volume delineation in RT of OPC, but a simple dynamic imaging protocol proved practicable and enabled simple data analysis techniques that show promise for complementing the information in static uptake values.

  7. The Ignalina NPP and Y2K Problem

    International Nuclear Information System (INIS)

    Medeliene, D.

    2000-01-01

    Work on preparing the hardware and software of the Ignalina NPP for the year 2000 was started in December 1998. First of all, a Y2K project team was formed comprising 29 specialists. Some of these are the most experienced computer specialist, others co-ordinate work on the Y2K problem at the divisions of the NPP using computers or microprocessors. The project head was appointed and the schedule of work confirmed. In accordance with the schedule, the work was divided into twelve stages. The results showed that the preparations were adequate. On the New Year night the specialists of the Ignalina NPP Emergency Operation Centre worked together with the managers of the plant. Relation with other Lithuanian and international organisations was established. No any Y2K related event happened

  8. Problem-Based Learning in the Life Science Classroom, K-12

    Science.gov (United States)

    McConnell, Tom; Parker, Joyce; Eberhardt, Janet

    2016-01-01

    "Problem-Based Learning in the Life Science Classroom, K-12" offers a great new way to ignite your creativity. Authors Tom McConnell, Joyce Parker, and Janet Eberhardt show you how to engage students with scenarios that represent real-world science in all its messy, thought-provoking glory. The scenarios prompt K-12 learners to immerse…

  9. Normal ordering problem and the extensions of the Stirling grammar

    Science.gov (United States)

    Ma, S.-M.; Mansour, T.; Schork, M.

    2014-04-01

    The purpose of this paper is to investigate the connection between context-free grammars and normal ordered problem, and then to explore various extensions of the Stirling grammar. We present grammatical characterizations of several well known combinatorial sequences, including the generalized Stirling numbers of the second kind related to the normal ordered problem and the r-Dowling polynomials. Also, possible avenues for future research are described.

  10. Matrix interdiction problem

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Feng [Los Alamos National Laboratory; Kasiviswanathan, Shiva [Los Alamos National Laboratory

    2010-01-01

    In the matrix interdiction problem, a real-valued matrix and an integer k is given. The objective is to remove k columns such that the sum over all rows of the maximum entry in each row is minimized. This combinatorial problem is closely related to bipartite network interdiction problem which can be applied to prioritize the border checkpoints in order to minimize the probability that an adversary can successfully cross the border. After introducing the matrix interdiction problem, we will prove the problem is NP-hard, and even NP-hard to approximate with an additive n{gamma} factor for a fixed constant {gamma}. We also present an algorithm for this problem that achieves a factor of (n-k) mUltiplicative approximation ratio.

  11. TOUR CONSTRUCTION HEURISTICS FOR AN ORDER SEQUENCING PROBLEM

    Directory of Open Access Journals (Sweden)

    De Villiers, A. P.

    2012-11-01

    Full Text Available An order picking system that requires pickers to move in a clockwise direction around a picking line with fixed locations is considered. The problem is divided into three tiers. The tier in which orders must be sequenced is addressed. Eight tour construction heuristics are developed and implemented for an order picking system operating in unidirectional picking lines. Two classes of tour construction heuristics the tour construction starting position ( and the tour construction ending position ( are developed to sequence orders in a picking line. All algorithms are tested and compared using real life data sets. The best solution quality was obtained by a heuristic with adaptations.

  12. Maximizing Total Profit in Two-agent Problem of Order Acceptance and Scheduling

    Directory of Open Access Journals (Sweden)

    Mohammad Reisi-Nafchi

    2017-03-01

    Full Text Available In competitive markets, attracting potential customers and keeping current customers is a survival condition for each company. So, paying attention to the requests of customers is important and vital. In this paper, the problem of order acceptance and scheduling has been studied, in which two types of customers or agents compete in a single machine environment. The objective is maximizing sum of the total profit of first agent's accepted orders and the total revenue of second agent. Therefore, only the first agent has penalty and its penalty function is lateness and the second agent's orders have a common due date and this agent does not accept any tardy order. To solve the problem, a mathematical programming, a heuristic algorithm and a pseudo-polynomial dynamic programming algorithm are proposed. Computational results confirm the ability of solving all problem instances up to 70 orders size optimally and also 93.12% of problem instances up to 150 orders size by dynamic programming.

  13. Assessing the Agreement Between Eo-Based Semi-Automated Landslide Maps with Fuzzy Manual Landslide Delineation

    Science.gov (United States)

    Albrecht, F.; Hölbling, D.; Friedl, B.

    2017-09-01

    Landslide mapping benefits from the ever increasing availability of Earth Observation (EO) data resulting from programmes like the Copernicus Sentinel missions and improved infrastructure for data access. However, there arises the need for improved automated landslide information extraction processes from EO data while the dominant method is still manual delineation. Object-based image analysis (OBIA) provides the means for the fast and efficient extraction of landslide information. To prove its quality, automated results are often compared to manually delineated landslide maps. Although there is awareness of the uncertainties inherent in manual delineations, there is a lack of understanding how they affect the levels of agreement in a direct comparison of OBIA-derived landslide maps and manually derived landslide maps. In order to provide an improved reference, we present a fuzzy approach for the manual delineation of landslides on optical satellite images, thereby making the inherent uncertainties of the delineation explicit. The fuzzy manual delineation and the OBIA classification are compared by accuracy metrics accepted in the remote sensing community. We have tested this approach for high resolution (HR) satellite images of three large landslides in Austria and Italy. We were able to show that the deviation of the OBIA result from the manual delineation can mainly be attributed to the uncertainty inherent in the manual delineation process, a relevant issue for the design of validation processes for OBIA-derived landslide maps.

  14. DNR 24K Lakes

    Data.gov (United States)

    Minnesota Department of Natural Resources — Medium scale lake polygons derived from the National Wetlands Inventory (NWI) polygons and MnDOT Basemap lake delineations. Integrated with the DNR 24K Streams...

  15. Minimizing transient influence in WHPA delineation: An optimization approach for optimal pumping rate schemes

    Science.gov (United States)

    Rodriguez-Pretelin, A.; Nowak, W.

    2017-12-01

    For most groundwater protection management programs, Wellhead Protection Areas (WHPAs) have served as primarily protection measure. In their delineation, the influence of time-varying groundwater flow conditions is often underestimated because steady-state assumptions are commonly made. However, it has been demonstrated that temporary variations lead to significant changes in the required size and shape of WHPAs. Apart from natural transient groundwater drivers (e.g., changes in the regional angle of flow direction and seasonal natural groundwater recharge), anthropogenic causes such as transient pumping rates are of the most influential factors that require larger WHPAs. We hypothesize that WHPA programs that integrate adaptive and optimized pumping-injection management schemes can counter transient effects and thus reduce the additional areal demand in well protection under transient conditions. The main goal of this study is to present a novel management framework that optimizes pumping schemes dynamically, in order to minimize the impact triggered by transient conditions in WHPA delineation. For optimizing pumping schemes, we consider three objectives: 1) to minimize the risk of pumping water from outside a given WHPA, 2) to maximize the groundwater supply and 3) to minimize the involved operating costs. We solve transient groundwater flow through an available transient groundwater and Lagrangian particle tracking model. The optimization problem is formulated as a dynamic programming problem. Two different optimization approaches are explored: I) the first approach aims for single-objective optimization under objective (1) only. The second approach performs multiobjective optimization under all three objectives where compromise pumping rates are selected from the current Pareto front. Finally, we look for WHPA outlines that are as small as possible, yet allow the optimization problem to find the most suitable solutions.

  16. Support for solving the Y2K problem in non-IT sector at KAERI.

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Tak; Hwang, In Ah [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-08-01

    An extensive survey is carried out for the Year 2000 (Y2K) problem at Korea Atomic Energy Research Institute. For the non-IT problems, several people have been dispatched to each department and/or research team to do the survey. They analyzed every equipment for possible Y2K problems and compiled a list of the equipments involved. During the survey, the 'No Problem' stickers are pasted on each equipment with no Y2K problems. For equipments with possible problems, we supplied the users with necessary documentations and the contact points for a proper help. For commonly used equipments such as the environmental radiation monitoring systems or the telephone exchanger, we generated specific action items and recommendations to the related departments in charge to do the proper actions. The survey took six months and about 16,000 machines were involved. 1 fig., 8 tabs. (Author)

  17. Vectorial Resilient PC(l) of Order k Boolean Functions from AG-Codes

    Institute of Scientific and Technical Information of China (English)

    Hao CHEN; Liang MA; Jianhua LI

    2011-01-01

    Propagation criteria and resiliency of vectorial Boolean functions are important for cryptographic purpose (see [1- 4, 7, 8, 10, 11, 16]). Kurosawa, Stoh [8] and Carlet [1]gave a construction of Boolean functions satisfying PC(l) of order k from binary linear or nonlinear codes. In this paper, the algebraic-geometric codes over GF(2m) are used to modify the Carlet and Kurosawa-Satoh's construction for giving vectorial resilient Boolean functions satisfying PC(l) of order k criterion. This new construction is compared with previously known results.

  18. Fourth-order discrete anisotropic boundary-value problems

    Directory of Open Access Journals (Sweden)

    Maciej Leszczynski

    2015-09-01

    Full Text Available In this article we consider the fourth-order discrete anisotropic boundary value problem with both advance and retardation. We apply the direct method of the calculus of variations and the mountain pass technique to prove the existence of at least one and at least two solutions. Non-existence of non-trivial solutions is also undertaken.

  19. Automated bond order assignment as an optimization problem.

    Science.gov (United States)

    Dehof, Anna Katharina; Rurainski, Alexander; Bui, Quang Bao Anh; Böcker, Sebastian; Lenhof, Hans-Peter; Hildebrandt, Andreas

    2011-03-01

    Numerous applications in Computational Biology process molecular structures and hence strongly rely not only on correct atomic coordinates but also on correct bond order information. For proteins and nucleic acids, bond orders can be easily deduced but this does not hold for other types of molecules like ligands. For ligands, bond order information is not always provided in molecular databases and thus a variety of approaches tackling this problem have been developed. In this work, we extend an ansatz proposed by Wang et al. that assigns connectivity-based penalty scores and tries to heuristically approximate its optimum. In this work, we present three efficient and exact solvers for the problem replacing the heuristic approximation scheme of the original approach: an A*, an ILP and an fixed-parameter approach (FPT) approach. We implemented and evaluated the original implementation, our A*, ILP and FPT formulation on the MMFF94 validation suite and the KEGG Drug database. We show the benefit of computing exact solutions of the penalty minimization problem and the additional gain when computing all optimal (or even suboptimal) solutions. We close with a detailed comparison of our methods. The A* and ILP solution are integrated into the open-source C++ LGPL library BALL and the molecular visualization and modelling tool BALLView and can be downloaded from our homepage www.ball-project.org. The FPT implementation can be downloaded from http://bio.informatik.uni-jena.de/software/.

  20. Is the K-quantum number conserved in the order-to-chaos transittion region?

    DEFF Research Database (Denmark)

    Benzoni...[], G.; Døssing, T.; Herskind, B.

    2005-01-01

    To study the order-to-chaos transition in nuclei we investigate the validity of the K-quantum number in the excited rapidly rotating 163Er nucleus, analyzing the variance and covariance of the spectrum fluctuations of ¿-cascades feeding into low-K and high-K bands. The data are compared...

  1. ASSESSING THE AGREEMENT BETWEEN EO-BASED SEMI-AUTOMATED LANDSLIDE MAPS WITH FUZZY MANUAL LANDSLIDE DELINEATION

    Directory of Open Access Journals (Sweden)

    F. Albrecht

    2017-09-01

    Full Text Available Landslide mapping benefits from the ever increasing availability of Earth Observation (EO data resulting from programmes like the Copernicus Sentinel missions and improved infrastructure for data access. However, there arises the need for improved automated landslide information extraction processes from EO data while the dominant method is still manual delineation. Object-based image analysis (OBIA provides the means for the fast and efficient extraction of landslide information. To prove its quality, automated results are often compared to manually delineated landslide maps. Although there is awareness of the uncertainties inherent in manual delineations, there is a lack of understanding how they affect the levels of agreement in a direct comparison of OBIA-derived landslide maps and manually derived landslide maps. In order to provide an improved reference, we present a fuzzy approach for the manual delineation of landslides on optical satellite images, thereby making the inherent uncertainties of the delineation explicit. The fuzzy manual delineation and the OBIA classification are compared by accuracy metrics accepted in the remote sensing community. We have tested this approach for high resolution (HR satellite images of three large landslides in Austria and Italy. We were able to show that the deviation of the OBIA result from the manual delineation can mainly be attributed to the uncertainty inherent in the manual delineation process, a relevant issue for the design of validation processes for OBIA-derived landslide maps.

  2. Approaching the Y2K problem, a need for rigorous check, careful solutions and readiness demonstration

    International Nuclear Information System (INIS)

    Hossu, A.D.

    1999-01-01

    The National Commission for Nuclear Activities Control, Bucharest, as a regulatory body adopted the IAEA guide and issued corresponding supplementary requirements for the facilities licensed to perform nuclear activities concerned with the Y2K problem in the area of operation of safeguard facilities and physical protection and control of nuclear materials. After the deadlines for reporting set for the utilities there will be a programmed regulatory body inspection to analyse the reported status in order to evaluate the status and determine the measures to be undertaken

  3. First-order system least-squares for second-order elliptic problems with discontinuous coefficients: Further results

    Energy Technology Data Exchange (ETDEWEB)

    Bloechle, B.; Manteuffel, T.; McCormick, S.; Starke, G.

    1996-12-31

    Many physical phenomena are modeled as scalar second-order elliptic boundary value problems with discontinuous coefficients. The first-order system least-squares (FOSLS) methodology is an alternative to standard mixed finite element methods for such problems. The occurrence of singularities at interface corners and cross-points requires that care be taken when implementing the least-squares finite element method in the FOSLS context. We introduce two methods of handling the challenges resulting from singularities. The first method is based on a weighted least-squares functional and results in non-conforming finite elements. The second method is based on the use of singular basis functions and results in conforming finite elements. We also share numerical results comparing the two approaches.

  4. Interactive Cadastral Boundary Delineation from Uav Data

    Science.gov (United States)

    Crommelinck, S.; Höfle, B.; Koeva, M. N.; Yang, M. Y.; Vosselman, G.

    2018-05-01

    Unmanned aerial vehicles (UAV) are evolving as an alternative tool to acquire land tenure data. UAVs can capture geospatial data at high quality and resolution in a cost-effective, transparent and flexible manner, from which visible land parcel boundaries, i.e., cadastral boundaries are delineable. This delineation is to no extent automated, even though physical objects automatically retrievable through image analysis methods mark a large portion of cadastral boundaries. This study proposes (i) a methodology that automatically extracts and processes candidate cadastral boundary features from UAV data, and (ii) a procedure for a subsequent interactive delineation. Part (i) consists of two state-of-the-art computer vision methods, namely gPb contour detection and SLIC superpixels, as well as a classification part assigning costs to each outline according to local boundary knowledge. Part (ii) allows a user-guided delineation by calculating least-cost paths along previously extracted and weighted lines. The approach is tested on visible road outlines in two UAV datasets from Germany. Results show that all roads can be delineated comprehensively. Compared to manual delineation, the number of clicks per 100 m is reduced by up to 86 %, while obtaining a similar localization quality. The approach shows promising results to reduce the effort of manual delineation that is currently employed for indirect (cadastral) surveying.

  5. Square matrices of order 2 theory, applications, and problems

    CERN Document Server

    Pop, Vasile

    2017-01-01

    This unique and innovative book presents an exciting and complete detail of all the important topics related to the theory of square matrices of order 2. The readers exploring every detailed aspect of matrix theory are gently led toward understanding advanced topics. They will follow every notion of matrix theory with ease, accumulating a thorough understanding of algebraic and geometric aspects of matrices of order 2. The prime jewel of this book is its offering of an unusual collection of problems, theoretically motivated, most of which are new, original, and seeing the light of publication for the first time in the literature. Nearly all of the exercises are presented with detailed solutions and vary in difficulty from easy to more advanced. Many problems are particularly challenging. These, and not only these, invite the reader to unleash their creativity and research capabilities and to discover their own methods of attacking a problem. Matrices have a vast practical importance to mathematics, science, a...

  6. On the formulation and numerical simulation of distributed-order fractional optimal control problems

    Science.gov (United States)

    Zaky, M. A.; Machado, J. A. Tenreiro

    2017-11-01

    In a fractional optimal control problem, the integer order derivative is replaced by a fractional order derivative. The fractional derivative embeds implicitly the time delays in an optimal control process. The order of the fractional derivative can be distributed over the unit interval, to capture delays of distinct sources. The purpose of this paper is twofold. Firstly, we derive the generalized necessary conditions for optimal control problems with dynamics described by ordinary distributed-order fractional differential equations (DFDEs). Secondly, we propose an efficient numerical scheme for solving an unconstrained convex distributed optimal control problem governed by the DFDE. We convert the problem under consideration into an optimal control problem governed by a system of DFDEs, using the pseudo-spectral method and the Jacobi-Gauss-Lobatto (J-G-L) integration formula. Next, we present the numerical solutions for a class of optimal control problems of systems governed by DFDEs. The convergence of the proposed method is graphically analyzed showing that the proposed scheme is a good tool for the simulation of distributed control problems governed by DFDEs.

  7. Computed tomography scout views vs. conventional radiography in body-packers – Delineation of body-packs and radiation dose in a porcine model

    Energy Technology Data Exchange (ETDEWEB)

    Ziegeler, Edvard, E-mail: edvard.ziegeler@campus.lmu.de [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Nussbaumstraße 20, 80336 Munich (Germany); Grimm, Jochen M., E-mail: jochen.grimm@med.lmu.de [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Nussbaumstraße 20, 80336 Munich (Germany); Wirth, Stefan, E-mail: tefan.wirth@med.lmu.de [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Nussbaumstraße 20, 80336 Munich (Germany); Uhl, Michael, E-mail: michael.uhl@polizei.bayern.de [Bavarian State Criminal Police Office, Maillingerstrasse 15, 80636 Munich (Germany); Reiser, Maximilian F., E-mail: Maximilian.Reiser@med.lmu.de [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Nussbaumstraße 20, 80336 Munich (Germany); Scherr, Michael K., E-mail: Michael.Scherr@med.lmu.de [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Nussbaumstraße 20, 80336 Munich (Germany)

    2012-12-15

    Objective: To compare abdominal computed tomography (CT) scout views with conventional radiography regarding radiation dose and delineation of drug packages in a porcine body-packer model. Materials and methods: Nine samples of illicit drugs packed in ovoid plastic containers were consecutively placed in the rectum of a 121.5 kg pig cadaver. Antero-posterior and lateral scout views were obtained at 120 kVp and 80 mA, 150 mA and 200 mA, respectively, using a 64-row MDCT. Scout views were compared with conventional abdominal antero-posterior radiographs (77 kV and 106 ± 13 mAs). Visibility of three body pack characteristics (wrapping, content, shape) was rated independently by two radiologists and summarized to a delineation score ranging from 0 to 9 with a score ≥6 representing sufficient delineation. Mean delineation scores were calculated for each conventional radiography and single plane scout view separately and for a combined rating of antero-posterior and lateral scout views. Results: Even the lowest single plane scout view delineation score (5.3 ± 2.0 for 80 mA lateral; 0.4 mSv; sensitivity = 44%) was significantly higher than for conventional radiographs (3.1 ± 2.5, p < 0.001; 2.4 ± 0.3 mSv; sensitivity = 11%). Combined reading of antero-posterior and lateral scout views 80 mA yielded sufficient delineation (6.2 ± 1.4; 0.8 mSv; sensitivity = 56%). Conclusions: All CT scout views showed significantly better delineation ratings and sensitivity than conventional radiographs. Scout views in two planes at 80 mA provided a sufficient level of delineation and a sensitivity five times higher than conventional radiography at less than one third of the radiation dose. In case of diagnostic insecurity, CT can be performed without additional logistical effort.

  8. Estimates for lower order eigenvalues of a clamped plate problem

    OpenAIRE

    Cheng, Qing-Ming; Huang, Guangyue; Wei, Guoxin

    2009-01-01

    For a bounded domain $\\Omega$ in a complete Riemannian manifold $M^n$, we study estimates for lower order eigenvalues of a clamped plate problem. We obtain universal inequalities for lower order eigenvalues. We would like to remark that our results are sharp.

  9. Order-Constrained Solutions in K-Means Clustering: Even Better than Being Globally Optimal

    Science.gov (United States)

    Steinley, Douglas; Hubert, Lawrence

    2008-01-01

    This paper proposes an order-constrained K-means cluster analysis strategy, and implements that strategy through an auxiliary quadratic assignment optimization heuristic that identifies an initial object order. A subsequent dynamic programming recursion is applied to optimally subdivide the object set subject to the order constraint. We show that…

  10. The Problem of World Order in Western IR Studies

    OpenAIRE

    Maria Victorovna Soljanova

    2016-01-01

    The article "Problem of world order in modern Western studies" is the study of one of the most debated issues in the science of international relations - world order. Discussion of the structure of world order is underway in various countries, both at the state level and in the expert community. Some researchers insist on the fact that after the end of the cold war, the collapse of the bipolar model of international relations, the world has become unipolar. Others argue that the increase in t...

  11. Dealing with the Y2K problem in German nuclear facilities

    International Nuclear Information System (INIS)

    Hagemann, A.

    1999-01-01

    General situation concerning Y2K problem related to german nuclear facilities is presented. Nuclear material used i Germany is owned by EURATOM and Germany is responsible to EURATOM as well as IAEA inspections. Systems of concern are monitoring and control systems, safety related systems and physical protection systems. Present situation is as follows: responsible project teams are formed, Y2K sensitive equipment is identified, designers are contacted, compliance tests specified and schedule of the proof established as of end of August 1999. Experiences obtained in overcoming the Y2K risks are cited

  12. Application of He's variational iteration method to the fifth-order boundary value problems

    International Nuclear Information System (INIS)

    Shen, S

    2008-01-01

    Variational iteration method is introduced to solve the fifth-order boundary value problems. This method provides an efficient approach to solve this type of problems without discretization and the computation of the Adomian polynomials. Numerical results demonstrate that this method is a promising and powerful tool for solving the fifth-order boundary value problems

  13. Data-Driven Model Order Reduction for Bayesian Inverse Problems

    KAUST Repository

    Cui, Tiangang; Youssef, Marzouk; Willcox, Karen

    2014-01-01

    One of the major challenges in using MCMC for the solution of inverse problems is the repeated evaluation of computationally expensive numerical models. We develop a data-driven projection- based model order reduction technique to reduce

  14. K+ and K- potentials in hadronic matter can be observed

    International Nuclear Information System (INIS)

    Sood, Aman D.; Hartnack, Ch.; Aichelin, Joerg

    2011-01-01

    One key question in the analysis of subthreshold kaon production is how to obtain information on the properties of strange mesons in dense nuclear matter. The principal problem for extracting precise information on these properties is, however, that almost all observables depend simultaneously not only on the K - potential but also on several other input quantities which are only vaguely known e.g. life time of Δ and in-medium modification of the cross section. The situation were much better if experiment provides an observable which depends on the K potentials only and which is not spoiled by other little or unknown quantities. Here the aim was to show that the ratio of the K + and K - momentum spectra at small momentum in light systems can be such an observable. In order to study this observable and in order to make sure that it does not depend on other input quantities the K - have been separated into 2 classes (by tracing back K - to its corresponding anti strange partner K + )

  15. A comparison of zero-order, first-order, and Monod biotransformation models

    International Nuclear Information System (INIS)

    Bekins, B.A.; Warren, E.; Godsy, E.M.

    1998-01-01

    Under some conditions, a first-order kinetic model is a poor representation of biodegradation in contaminated aquifers. Although it is well known that the assumption of first-order kinetics is valid only when substrate concentration, S, is much less than the half-saturation constant, K S , this assumption is often made without verification of this condition. The authors present a formal error analysis showing that the relative error in the first-order approximation is S/K S and in the zero-order approximation the error is K S /S. They then examine the problems that arise when the first-order approximation is used outside the range for which it is valid. A series of numerical simulations comparing results of first- and zero-order rate approximations to Monod kinetics for a real data set illustrates that if concentrations observed in the field are higher than K S , it may be better to model degradation using a zero-order rate expression. Compared with Monod kinetics, extrapolation of a first-order rate to lower concentrations under-predicts the biotransformation potential, while extrapolation to higher concentrations may grossly over-predict the transformation rate. A summary of solubilities and Monod parameters for aerobic benzene, toluene, and xylene (BTX) degradation shows that the a priori assumption of first-order degradation kinetics at sites contaminated with these compounds is not valid. In particular, out of six published values of K S for toluene, only one is greater than 2 mg/L, indicating that when toluene is present in concentrations greater than about a part per million, the assumption of first-order kinetics may be invalid. Finally, the authors apply an existing analytical solution for steady-state one-dimensional advective transport with Monod degradation kinetics to a field data set

  16. New high order FDTD method to solve EMC problems

    Directory of Open Access Journals (Sweden)

    N. Deymier

    2015-10-01

    Full Text Available In electromagnetic compatibility (EMC context, we are interested in developing new ac- curate methods to solve efficiently and accurately Maxwell’s equations in the time domain. Indeed, usual methods such as FDTD or FVTD present im- portant dissipative and/or dispersive errors which prevent to obtain a good numerical approximation of the physical solution for a given industrial scene unless we use a mesh with a very small cell size. To avoid this problem, schemes like the Discontinuous Galerkin (DG method, based on higher order spa- tial approximations, have been introduced and stud- ied on unstructured meshes. However the cost of this kind of method can become prohibitive accord- ing to the mesh used. In this paper, we first present a higher order spatial approximation method on carte- sian meshes. It is based on a finite element ap- proach and recovers at the order 1 the well-known Yee’s schema. Next, to deal with EMC problem, a non-oriented thin wire formalism is proposed for this method. Finally, several examples are given to present the benefits of this new method by compar- ison with both Yee’s schema and DG approaches.

  17. Impact of Y2K problem on physical protection system

    International Nuclear Information System (INIS)

    Kumar, R.; Swadia, N.S.; Zanwar, P.S.; Mishra, G.P.; Salunke, A.S.; Nigam, R.K.

    1999-01-01

    Year 2000 related system failures/problems in Physical Protection System pose no threat to general safety and functioning of any nuclear facility. But there can be potential security threats having radiation safety and non-proliferation concern and hence should be given due importance. Reviewing and testing Physical Protection System for Y2K compliance are easier than other systems as it does not directly affect operation of the plant. The existing emergency response capability at the nuclear facilities should be utilizes effectively to mitigate any Y2K induced events on Physical Protection System with dedicated manpower and channeled efforts

  18. Problems with Excessive Residual Lower Leg Length in Pediatric Amputees

    OpenAIRE

    Osebold, William R; Lester, Edward L; Christenson, Donald M

    2001-01-01

    We studied six pediatric amputees with long below-knee residual limbs, in order to delineate their functional and prosthetic situations, specifically in relation to problems with fitting for dynamic-response prosthetic feet. Three patients had congenital pseudoarthrosis of the tibia secondary to neurofibromatosis, one had fibular hemimelia, one had a traumatic amputation, and one had amputation secondary to burns. Five patients had Syme's amputations, one had a Boyd amputation. Ages at amputa...

  19. Slic Superpixels for Object Delineation from Uav Data

    Science.gov (United States)

    Crommelinck, S.; Bennett, R.; Gerke, M.; Koeva, M. N.; Yang, M. Y.; Vosselman, G.

    2017-08-01

    Unmanned aerial vehicles (UAV) are increasingly investigated with regard to their potential to create and update (cadastral) maps. UAVs provide a flexible and low-cost platform for high-resolution data, from which object outlines can be accurately delineated. This delineation could be automated with image analysis methods to improve existing mapping procedures that are cost, time and labor intensive and of little reproducibility. This study investigates a superpixel approach, namely simple linear iterative clustering (SLIC), in terms of its applicability to UAV data. The approach is investigated in terms of its applicability to high-resolution UAV orthoimages and in terms of its ability to delineate object outlines of roads and roofs. Results show that the approach is applicable to UAV orthoimages of 0.05 m GSD and extents of 100 million and 400 million pixels. Further, the approach delineates the objects with the high accuracy provided by the UAV orthoimages at completeness rates of up to 64 %. The approach is not suitable as a standalone approach for object delineation. However, it shows high potential for a combination with further methods that delineate objects at higher correctness rates in exchange of a lower localization quality. This study provides a basis for future work that will focus on the incorporation of multiple methods for an interactive, comprehensive and accurate object delineation from UAV data. This aims to support numerous application fields such as topographic and cadastral mapping.

  20. The Problem of World Order in Western IR Studies

    Directory of Open Access Journals (Sweden)

    Maria Victorovna Soljanova

    2016-01-01

    Full Text Available The article "Problem of world order in modern Western studies" is the study of one of the most debated issues in the science of international relations - world order. Discussion of the structure of world order is underway in various countries, both at the state level and in the expert community. Some researchers insist on the fact that after the end of the cold war, the collapse of the bipolar model of international relations, the world has become unipolar. Others argue that the increase in the number of centers of power and the need for a multilateral approach to solving global problems (terrorism, proliferation of weapons of mass destruction, environmental and climate issues talking about the formation of multipolarity. However, it should be recognized that currently no widely accepted theoretical and conceptual apparatus, which complicates not only the study of the world order, but makes it impossible to search for common approaches of the international community in solving the problems associated with global development, new challenges and threats. The author of this article seeks to research and analyze the various theoretical paradigms (neo-realism, neo-liberalism, institutionalism, neo-marxism, etc. and concepts to form a coherent picture of the structure of the world system, its main features and to offer readers the vision of the concept of "world order". Thus, the article notes that the multidimensional structure of the modern system of international relations established after the end of the cold war is so complex that none of the concepts can claim to accurate interpretation of the world order. The modern system differs from systems of the past centuries. Characteristics inherent in it (on the one hand, the increasing global processes in economy, politics, culture, etc., on the other, the attraction to return to the concept of "nation state", the closure of borders, the disintegration, require new approaches to the study of world

  1. Quadratic third-order tensor optimization problem with quadratic constraints

    Directory of Open Access Journals (Sweden)

    Lixing Yang

    2014-05-01

    Full Text Available Quadratically constrained quadratic programs (QQPs problems play an important modeling role for many diverse problems. These problems are in general NP hard and numerically intractable. Semidenite programming (SDP relaxations often provide good approximate solutions to these hard problems. For several special cases of QQP, e.g., convex programs and trust region subproblems, SDP relaxation provides the exact optimal value, i.e., there is a zero duality gap. However, this is not true for the general QQP, or even the QQP with two convex constraints, but a nonconvex objective.In this paper, we consider a certain QQP where the variable is neither vector nor matrix but a third-order tensor. This problem can be viewed as a generalization of the ordinary QQP with vector or matrix as it's variant. Under some mild conditions, we rst show that SDP relaxation provides exact optimal solutions for the original problem. Then we focus on two classes of homogeneous quadratic tensor programming problems which have no requirements on the constraints number. For one, we provide an easily implemental polynomial time algorithm to approximately solve the problem and discuss the approximation ratio. For the other, we show there is no gap between the SDP relaxation and itself.

  2. Forest Delineation Based on Airborne LIDAR Data

    Directory of Open Access Journals (Sweden)

    Norbert Pfeifer

    2012-03-01

    Full Text Available The delineation of forested areas is a critical task, because the resulting maps are a fundamental input for a broad field of applications and users. Different national and international forest definitions are available for manual or automatic delineation, but unfortunately most definitions lack precise geometrical descriptions for the different criteria. A mandatory criterion in forest definitions is the criterion of crown coverage (CC, which defines the proportion of the forest floor covered by the vertical projection of the tree crowns. For loosely stocked areas, this criterion is especially critical, because the size and shape of the reference area for calculating CC is not clearly defined in most definitions. Thus current forest delineations differ and tend to be non-comparable because of different settings for checking the criterion of CC in the delineation process. This paper evaluates a new approach for the automatic delineation of forested areas, based on airborne laser scanning (ALS data with a clearly defined method for calculating CC. The new approach, the ‘tree triples’ method, is based on defining CC as a relation between the sum of the crown areas of three neighboring trees and the area of their convex hull. The approach is applied and analyzed for two study areas in Tyrol, Austria. The selected areas show a loosely stocked forest at the upper timberline and a fragmented forest on the hillside. The fully automatic method presented for delineating forested areas from ALS data shows promising results with an overall accuracy of 96%, and provides a beneficial tool for operational applications.

  3. SLIC superpixels for object delineation UAV data

    NARCIS (Netherlands)

    Crommelinck, Sophie Charlotte; Bennett, R.M.; Gerke, Markus; Koeva, M.N.; Yang, M.Y.; Vosselman, G.; Stachniss, C.; Förstner, W.; Schneider, J.

    2017-01-01

    Unmanned aerial vehicles (UAV) are increasingly investigated with regard to their potential to create and update (cadastral) maps. UAVs provide a flexible and low-cost platform for high-resolution data, from which object outlines can be accurately delineated. This delineation could be automated with

  4. Data-Driven Model Order Reduction for Bayesian Inverse Problems

    KAUST Repository

    Cui, Tiangang

    2014-01-06

    One of the major challenges in using MCMC for the solution of inverse problems is the repeated evaluation of computationally expensive numerical models. We develop a data-driven projection- based model order reduction technique to reduce the computational cost of numerical PDE evaluations in this context.

  5. Order Reduction in High-Order Runge-Kutta Methods for Initial Boundary Value Problems

    OpenAIRE

    Rosales, Rodolfo Ruben; Seibold, Benjamin; Shirokoff, David; Zhou, Dong

    2017-01-01

    This paper studies the order reduction phenomenon for initial-boundary-value problems that occurs with many Runge-Kutta time-stepping schemes. First, a geometric explanation of the mechanics of the phenomenon is provided: the approximation error develops boundary layers, induced by a mismatch between the approximation error in the interior and at the boundaries. Second, an analysis of the modes of the numerical scheme is conducted, which explains under which circumstances boundary layers pers...

  6. Lowest order Virtual Element approximation of magnetostatic problems

    Science.gov (United States)

    Beirão da Veiga, L.; Brezzi, F.; Dassi, F.; Marini, L. D.; Russo, A.

    2018-04-01

    We give here a simplified presentation of the lowest order Serendipity Virtual Element method, and show its use for the numerical solution of linear magneto-static problems in three dimensions. The method can be applied to very general decompositions of the computational domain (as is natural for Virtual Element Methods) and uses as unknowns the (constant) tangential component of the magnetic field $\\mathbf{H}$ on each edge, and the vertex values of the Lagrange multiplier $p$ (used to enforce the solenoidality of the magnetic induction $\\mathbf{B}=\\mu\\mathbf{H}$). In this respect the method can be seen as the natural generalization of the lowest order Edge Finite Element Method (the so-called "first kind N\\'ed\\'elec" elements) to polyhedra of almost arbitrary shape, and as we show on some numerical examples it exhibits very good accuracy (for being a lowest order element) and excellent robustness with respect to distortions.

  7. Iterative Otsu's method for OCT improved delineation in the aorta wall

    Science.gov (United States)

    Alonso, Daniel; Real, Eusebio; Val-Bernal, José F.; Revuelta, José M.; Pontón, Alejandro; Calvo Díez, Marta; Mayorga, Marta; López-Higuera, José M.; Conde, Olga M.

    2015-07-01

    Degradation of human ascending thoracic aorta has been visualized with Optical Coherence Tomography (OCT). OCT images of the vessel wall exhibit structural degradation in the media layer of the artery, being this disorder the final trigger of the pathology. The degeneration in the vessel wall appears as low-reflectivity areas due to different optical properties of acidic polysaccharides and mucopolysaccharides in contrast with typical ordered structure of smooth muscle cells, elastin and collagen fibers. An OCT dimension indicator of wall degradation can be generated upon the spatial quantification of the extension of degraded areas in a similar way as conventional histopathology. This proposed OCT marker can offer in the future a real-time clinical perception of the vessel status to help cardiovascular surgeons in vessel repair interventions. However, the delineation of degraded areas on the B-scan image from OCT is sometimes difficult due to presence of speckle noise, variable signal to noise ratio (SNR) conditions on the measurement process, etc. Degraded areas can be delimited by basic thresholding techniques taking advantage of disorders evidences in B-scan images, but this delineation is not optimum in the aorta samples and requires complex additional processing stages. This work proposes an optimized delineation of degraded areas within the aorta wall, robust to noisy environments, based on the iterative application of Otsu's thresholding method. Results improve the delineation of wall anomalies compared with the simple application of the algorithm. Achievements could be also transferred to other clinical scenarios: carotid arteries, aorto-iliac or ilio-femoral sections, intracranial, etc.

  8. Fourth generation CP violation effects on B-->Kpi, phiK, and rhoK in next-to-leading-order perturbative QCD.

    Science.gov (United States)

    Hou, Wei-Shu; Li, Hsiang-nan; Mishima, Satoshi; Nagashima, Makiko

    2007-03-30

    We study the effect from a sequential fourth generation quark on penguin-dominated two-body nonleptonic B meson decays in the next-to-leading order perturbative QCD formalism. With an enhancement of the color-suppressed tree amplitude and possibility of a new CP phase in the electroweak penguin amplitude, we can account better for A(CP)(B(0)-->K+ pi-)-A(CP)(B+-->K+ pi0). Taking |V(t's)V(t'b)| approximately 0.02 with a phase just below 90 degrees, which is consistent with the b-->sl+ l- rate and the B(s) mixing parameter Deltam(B)(s), we find a downward shift in the mixing-induced CP asymmetries of B(0)-->K(S)(pi 0) and phi(K)(S). The predicted behavior for B(0)-->rho(0)(K)(S) is opposite.

  9. 12 CFR 228.41 - Assessment area delineation.

    Science.gov (United States)

    2010-01-01

    ... does not evaluate the bank's delineation of its assessment area(s) as a separate performance criterion..., such as those consumer loans on which the bank elects to have its performance assessed). (d... area(s) delineated by a bank in its evaluation of the bank's CRA performance unless the Board...

  10. Local order and concentration fluctuations in K-Pb and Rb-Pb alloys

    International Nuclear Information System (INIS)

    Akinlade, O.

    1992-08-01

    The concentration fluctuations in the long wavelength limit S cc (0), short range order parameter and free energy of mixing of K-Pb and Rb-Pb alloys have been studied within the framework of the quasi-chemical theory. It is observed that the simple model could be used to shed more insight into the nature of chemical ordering that exists in such strongly compound forming binary alloys. (author). 19 refs, 6 figs, 1 tab

  11. Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems

    OpenAIRE

    Ortiz-Bayliss, José Carlos; Amaya, Ivan; Conant-Pablos, Santiago Enrique; Terashima-Marín, Hugo

    2018-01-01

    When solving constraint satisfaction problems (CSPs), it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differen...

  12. Symmetry Reduction and Cauchy Problems for a Class of Fourth-Order Evolution Equations

    International Nuclear Information System (INIS)

    Li Jina; Zhang Shunli

    2008-01-01

    We exploit higher-order conditional symmetry to reduce initial-value problems for evolution equations to Cauchy problems for systems of ordinary differential equations (ODEs). We classify a class of fourth-order evolution equations which admit certain higher-order generalized conditional symmetries (GCSs) and give some examples to show the main reduction procedure. These reductions cannot be derived within the framework of the standard Lie approach, which hints that the technique presented here is something essential for the dimensional reduction of evolution equations

  13. 12 CFR 345.41 - Assessment area delineation.

    Science.gov (United States)

    2010-01-01

    ... the bank's delineation of its assessment area(s) as a separate performance criterion, but the FDIC..., such as those consumer loans on which the bank elects to have its performance assessed). (d... area(s) delineated by a bank in its evaluation of the bank's CRA performance unless the FDIC determines...

  14. Effects of high-order deformation on high-K isomers in superheavy nuclei

    International Nuclear Information System (INIS)

    Liu, H. L.; Bertulani, C. A.; Xu, F. R.; Walker, P. M.

    2011-01-01

    Using, for the first time, configuration-constrained potential-energy-surface calculations with the inclusion of β 6 deformation, we find remarkable effects of the high-order deformation on the high-K isomers in 254 No, the focus of recent spectroscopy experiments on superheavy nuclei. For shapes with multipolarity six, the isomers are more tightly bound and, microscopically, have enhanced deformed shell gaps at N=152 and Z=100. The inclusion of β 6 deformation significantly improves the description of the very heavy high-K isomers.

  15. K. Schwarzschild's problem in radiation transfer theory

    International Nuclear Information System (INIS)

    Rutily, B.; Chevallier, L.; Pelkowski, J.

    2006-01-01

    We solve exactly the problem of a finite slab receiving an isotropic radiation on one side and no radiation on the other side. This problem-to be more precise the calculation of the source function within the slab-was first formulated by K. Schwarzschild in 1914. We first solve it for unspecified albedos and optical thicknesses of the atmosphere, in particular for an albedo very close to 1 and a very large optical thickness in view of some astrophysical applications. Then we focus on the conservative case (albedo=1), which is of great interest for the modeling of grey atmospheres in radiative equilibrium. Ten-figure tables of the conservative source function are given. From the analytical expression of this function, we deduce (1) a simple relation between the effective temperature of a grey atmosphere in radiative equilibrium and the temperature of the black body that irradiates it (2) the temperature at any point of the atmosphere when it is in local thermodynamical equilibrium. This temperature distribution is the counterpart, for a finite slab, of Hopf's distribution in a half-space. Its graphical representation is given for various optical thicknesses of the atmosphere

  16. An algorithm for solving initial value problems of third order ordinary ...

    African Journals Online (AJOL)

    Abstract. We propose an implicit multi-step method for the solution of initial value problems (IVPs) of third order ordinary differential equations (ODE) which does not require reducing the ODE to first order before solving. The development of the method is based on collocation of the differential system and interpolation of the ...

  17. Market delineation and system competition. The 'Bedarfsmarktkonzept' on trial; Marktabgrenzung und Systemwettbewerb. Das Bedarfsmarktkonzept auf dem Pruefstand

    Energy Technology Data Exchange (ETDEWEB)

    Vahrenholt, Oliver

    2011-07-01

    The fundamental research question of this thesis is whether, and under conditions, competitive constraints arising out of competition between systems should be reflected in antitrust market delineation. In order to answer this question, it is necessary to understand the function of market delineation in antitrust law. This is the first research question the thesis addresses. The function of market delineation is intrinsically tied to the concept of market power. Market power and its possible negative effects on total welfare and especially on consumer welfare serve as the central legitimation for governmental intervention into the free play of market forces. In order to see how system competition fits into this free play of market forces and how market power can be established in light of these constraining forces, the central economic mechanism of system competition have to be understood. This leads to the second research question to be answered by this dissertation. The final, central question raised and answered in this thesis is how can market delineation perform its task in the presence of system competition forces, and which concepts are most suitable for accomplishing this end. A concrete concept - devised for the needs of ''everyday'' antitrust practice - is given at the end of this work. And, with this concept, the research goal is achieved: to constructively criticize the Bedarfsmarktkonzept as a market delineation instrument in cases of system competition.

  18. A capacitated vehicle routing problem with order available time in e-commerce industry

    Science.gov (United States)

    Liu, Ling; Li, Kunpeng; Liu, Zhixue

    2017-03-01

    In this article, a variant of the well-known capacitated vehicle routing problem (CVRP) called the capacitated vehicle routing problem with order available time (CVRPOAT) is considered, which is observed in the operations of the current e-commerce industry. In this problem, the orders are not available for delivery at the beginning of the planning period. CVRPOAT takes all the assumptions of CVRP, except the order available time, which is determined by the precedent order picking and packing stage in the warehouse of the online grocer. The objective is to minimize the sum of vehicle completion times. An efficient tabu search algorithm is presented to tackle the problem. Moreover, a Lagrangian relaxation algorithm is developed to obtain the lower bounds of reasonably sized problems. Based on the test instances derived from benchmark data, the proposed tabu search algorithm is compared with a published related genetic algorithm, as well as the derived lower bounds. Also, the tabu search algorithm is compared with the current operation strategy of the online grocer. Computational results indicate that the gap between the lower bounds and the results of the tabu search algorithm is small and the tabu search algorithm is superior to the genetic algorithm. Moreover, the CVRPOAT formulation together with the tabu search algorithm performs much better than the current operation strategy of the online grocer.

  19. The IAEA and Y2K. The Agency's action plan on the year 2000 problem

    International Nuclear Information System (INIS)

    Cherif, H.S.; Winkels, J.

    1999-01-01

    The article describes the aims of it IAEA action plan concerned with Year 2000 (Y2K) problem and the results achieved during four years of work, including the technical documents dealing with the Y2K computer problem, published by IAEA. This include IAEA systems and operations, contingency plans, coordination in the United Nations system. Through the IAEA Internet site, a series of Web pages were developed by the Division of Public Information to co-ordinate the global exchange of information on the IAEA Y2K activities and related topics. The site is open to Member States and international organisations within and outside United Nations system

  20. The Cauchy Problem for a Fifth-Order Dispersive Equation

    OpenAIRE

    Wang, Hongjun; Liu, Yongqi; Chen, Yongqiang

    2014-01-01

    This paper is devoted to studying the Cauchy problem for a fifth-order equation. We prove that it is locally well-posed for the initial data in the Sobolev space ${H}^{s}(\\mathbf{R})$ with $s\\ge 1/4$ . We also establish the ill-posedness for the initial data in ${H}^{s}(\\mathbf{R})$ with $s

  1. Improved business driveway delineation in urban work zones.

    Science.gov (United States)

    2015-04-01

    This report documents the efforts and results of a two-year research project aimed at improving driveway : delineation in work zones. The first year of the project included a closed-course study to identify the most : promising driveway delineation a...

  2. Study on delineation of tumor volume of primary locally advanced nasopharyngeal carcinoma after induction chemotherapy

    International Nuclear Information System (INIS)

    Long Jinhua; Dong Shi; Jin Feng; Wu Weili; Gan Jiaying; Chen Haixia; Li Yuanyuan; Gong Xiuyun

    2012-01-01

    Objective: To investigate the delineation of gross tumor volume (GTV) in locally advanced nasopharyngeal carcinoma (LANC) according to imageological changes before and after induction chemotherapy (IC) in order to decrease high dose area and protect normal tissue better. Methods: Between Mar 2010 to Jan 2011, 11 patients with LANC were enrolled and treated with TPF regimen followed by intensity-modulated radiotherapy (IMRT) with concurrent chemotherapy, target volumes were delineated based on fused CT imaging before and after IC following project determination. Tumor target volumes after and before IC were respectively delineated according to imaging tumor residues and were overlaid by CTV nx in order to ensure radical doses for the imaging tumor volume before IC, the resulting differences of tumor target volumes of IC before and after were measured and analyzed by paired t-test. Results: Before and after IC, the average volumes of GTV nx were respectively 44.72 cm 3 and 28.87 (t=3.89, P=0.003), the average volumes of GTV nd were respectively 32.76 cm 3 and 19.82 cm 3 (t=2.47, P=0.033), the volumes of maximum dose area in brainstem and spinal cord as well as eyeball decreased (t=2.93-4.59, all P<0.05). Conclusions: LANC treated by 3 cycle TPF regimen followed by IMRT with concurrent chemotherapy shows significant shrinkage of tumor volume. The volume of high dose region which caused by normally recovered tissues were decreased by re-delineation of target volume in brainstem and spinal cord as well as eyeball of CT images after IC. (authors)

  3. Variable order one-step methods for initial value problems I ...

    African Journals Online (AJOL)

    A class of variable order one-step integrators is proposed for Initial Value Problems (IVPs) in Ordinary Differential Equations (ODEs). It is based on a rational interpolant. Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 91-96 ...

  4. Rethinking pedagogy for second-order differential equations: a simplified approach to understanding well-posed problems

    Science.gov (United States)

    Tisdell, Christopher C.

    2017-07-01

    Knowing an equation has a unique solution is important from both a modelling and theoretical point of view. For over 70 years, the approach to learning and teaching 'well posedness' of initial value problems (IVPs) for second- and higher-order ordinary differential equations has involved transforming the problem and its analysis to a first-order system of equations. We show that this excursion is unnecessary and present a direct approach regarding second- and higher-order problems that does not require an understanding of systems.

  5. Delineating spring recharge areas in a fractured sandstone aquifer (Luxembourg) based on pesticide mass balance

    Science.gov (United States)

    Farlin, J.; Drouet, L.; Gallé, T.; Pittois, D.; Bayerle, M.; Braun, C.; Maloszewski, P.; Vanderborght, J.; Elsner, M.; Kies, A.

    2013-06-01

    A simple method to delineate the recharge areas of a series of springs draining a fractured aquifer is presented. Instead of solving the flow and transport equations, the delineation is reformulated as a mass balance problem assigning arable land in proportion to the pesticide mass discharged annually in a spring at minimum total transport cost. The approach was applied to the Luxembourg Sandstone, a fractured-rock aquifer supplying half of the drinking water for Luxembourg, using the herbicide atrazine. Predictions of the recharge areas were most robust in situations of strong competition by neighbouring springs while the catchment boundaries for isolated springs were extremely sensitive to the parameter controlling flow direction. Validation using a different pesticide showed the best agreement with the simplest model used, whereas using historical crop-rotation data and spatially distributed soil-leaching data did not improve predictions. The whole approach presents the advantage of integrating objectively information on land use and pesticide concentration in spring water into the delineation of groundwater recharge zones in a fractured-rock aquifer.

  6. Charm quark contribution to K+ ---> pi+ nu anti-nu at next-to-next-to-leading order

    Energy Technology Data Exchange (ETDEWEB)

    Buras, Andrzej J.; /Munich, Tech. U.; Gorbahn, Martin; /Durham U., IPPP /Karlsruhe U., TTP; Haisch, Ulrich; /Fermilab /Zurich U.; Nierste, Ulrich; /Karlsruhe U., TTP

    2006-03-01

    The authors calculate the complete next-to-next-to-leading order QCD corrections to the charm contribution of the rare decay K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}. They encounter several new features, which were absent in lower orders. They discuss them in detail and present the results for the two-loop matching conditions of the Wilson coefficients, the three-loop anomalous dimensions, and the two-loop matrix elements of the relevant operators that enter the next-to-next-to-leading order renormalization group analysis of the Z-penguin and the electroweak box contribution. The inclusion of the next-to-next-to-leading order QCD corrections leads to a significant reduction of the theoretical uncertainty from {+-} 9.8% down to {+-} 2.4% in the relevant parameter P{sub c}(X), implying the leftover scale uncertainties in {Beta}(K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}) and in the determination of |V{sub td}|, sin 2{beta}, and {gamma} from the K {yields} {pi}{nu}{bar {nu}} system to be {+-} 1.3%, {+-} 1.0%, {+-} 0.006, and {+-} 1.2{sup o}, respectively. For the charm quark {ovr MS} mass m{sub c}(m{sub c}) = (1.30 {+-} 0.05) GeV and |V{sub us}| = 0.2248 the next-to-leading order value P{sub c}(X) = 0.37 {+-} 0.06 is modified to P{sub c}(X) = 0.38 {+-} 0.04 at the next-to-next-to-leading order level with the latter error fully dominated by the uncertainty in m{sub c}(m{sub c}). They present tables for P{sub c}(X) as a function of m{sub c}(m{sub c}) and {alpha}{sub s}(M{sub z}) and a very accurate analytic formula that summarizes these two dependences as well as the dominant theoretical uncertainties. Adding the recently calculated long-distance contributions they find {Beta}(K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}) = (8.0 {+-} 1.1) x 10{sup -11} with the present uncertainties in m{sub c}(m{sub c}) and the Cabibbo-Kobayashi-Maskawa elements being the dominant individual sources in the quoted error. They also emphasize that improved calculations of the long

  7. The Y2K problem and management strategies for the individual practitioner.

    Science.gov (United States)

    Alex, J C; Jassin, B M

    1999-01-01

    This article will detail concisely the nature of the Y2K problem, how it could affect your computer systems and your business, and what measures you can institute to minimize and/or eliminate computer failure as you enter the year 2000.

  8. Constructive Solution of Ellipticity Problem for the First Order Differential System

    Directory of Open Access Journals (Sweden)

    Vladimir E. Balabaev

    2017-01-01

    Full Text Available We built first order elliptic systems with any possible number of unknown functions and the maximum possible number of unknowns, i.e, in general. These systems provide the basis for studying the properties of any first order elliptic systems. The study of the Cauchy-Riemann system and its generalizations led to the identification of a class of elliptic systems of first-order of a special structure. An integral representation of solutions is of great importance in the study of these systems. Only by means of a constructive method of integral representations we can solve a number of problems in the theory of elliptic systems related mainly to the boundary properties of solutions. The obtained integral representation could be applied to solve a number of problems that are hard to solve, if you rely only on the non-constructive methods. Some analogues of the theorems of Liouville, Weierstrass, Cauchy, Gauss, Morera, an analogue of Green’s formula are established, as well as an analogue of the maximum principle. The used matrix operators allow the new structural arrangement of the maximum number of linearly independent vector fields on spheres of any possible dimension. Also the built operators allow to obtain a constructive solution of the extended problem ”of the sum of squares” known in algebra. 

  9. Higher-order schemes for the Laplace transformation method for parabolic problems

    KAUST Repository

    Douglas, C.

    2011-01-01

    In this paper we solve linear parabolic problems using the three stage noble algorithms. First, the time discretization is approximated using the Laplace transformation method, which is both parallel in time (and can be in space, too) and extremely high order convergent. Second, higher-order compact schemes of order four and six are used for the the spatial discretization. Finally, the discretized linear algebraic systems are solved using multigrid to show the actual convergence rate for numerical examples, which are compared to other numerical solution methods. © 2011 Springer-Verlag.

  10. N-order Darboux transformation and a spectral problem on semiaxis

    OpenAIRE

    Bagrov, Vladislav G.; Samsonov, Boris F.; Shekoyan, L. A.

    1998-01-01

    N-order Darboux transformation operator is defined on the basis of a general notion of transformation operators. Factorisation properties of this operator are studied. The Darboux transformation operator technique is applied to construct and investigate potentials with bound states at arbitrary energies for the spectral problem on semiaxis.

  11. Spatial 't Hooft loop to cubic order in hot QCD

    CERN Document Server

    Giovannangeli, P.

    2002-01-01

    Spatial 't Hooft loops of strength k measure the qualitative change in the behaviour of electric colour flux in confined and deconfined phase of SU (N) gauge theory. They show an area law in the deconfined phase, known analytica lly to two loop order with a ``k-scaling'' law k(N-k). In this paper we comput e the O(g^3) correction to the tension. It is due to neutral gluon fields that get their mass through interaction with the wall. The simple k-scaling is lost in cubic order. The generic problem of non-convexity shows up in this order an d the cure is provided. The result for large N is explicitely given. We show tha t nonperturbative effects appear at O(g^5).

  12. Heterogeneous quantum computing for satellite constellation optimization: solving the weighted k-clique problem

    Science.gov (United States)

    Bass, Gideon; Tomlin, Casey; Kumar, Vaibhaw; Rihaczek, Pete; Dulny, Joseph, III

    2018-04-01

    NP-hard optimization problems scale very rapidly with problem size, becoming unsolvable with brute force methods, even with supercomputing resources. Typically, such problems have been approximated with heuristics. However, these methods still take a long time and are not guaranteed to find an optimal solution. Quantum computing offers the possibility of producing significant speed-up and improved solution quality. Current quantum annealing (QA) devices are designed to solve difficult optimization problems, but they are limited by hardware size and qubit connectivity restrictions. We present a novel heterogeneous computing stack that combines QA and classical machine learning, allowing the use of QA on problems larger than the hardware limits of the quantum device. These results represent experiments on a real-world problem represented by the weighted k-clique problem. Through this experiment, we provide insight into the state of quantum machine learning.

  13. An adaptive simplex cut-cell method for high-order discontinuous Galerkin discretizations of elliptic interface problems and conjugate heat transfer problems

    Science.gov (United States)

    Sun, Huafei; Darmofal, David L.

    2014-12-01

    In this paper we propose a new high-order solution framework for interface problems on non-interface-conforming meshes. The framework consists of a discontinuous Galerkin (DG) discretization, a simplex cut-cell technique, and an output-based adaptive scheme. We first present a DG discretization with a dual-consistent output evaluation for elliptic interface problems on interface-conforming meshes, and then extend the method to handle multi-physics interface problems, in particular conjugate heat transfer (CHT) problems. The method is then applied to non-interface-conforming meshes using a cut-cell technique, where the interface definition is completely separate from the mesh generation process. No assumption is made on the interface shape (other than Lipschitz continuity). We then equip our strategy with an output-based adaptive scheme for an accurate output prediction. Through numerical examples, we demonstrate high-order convergence for elliptic interface problems and CHT problems with both smooth and non-smooth interface shapes.

  14. Delineating Neural Structures of Developmental Human Brains with Diffusion Tensor Imaging

    Directory of Open Access Journals (Sweden)

    Hao Huang

    2010-01-01

    Full Text Available The human brain anatomy is characterized by dramatic structural changes during fetal development. It is extraordinarily complex and yet its origin is a simple tubular structure. Revealing detailed anatomy at different stages of brain development not only aids in understanding this highly ordered process, but also provides clues to detect abnormalities caused by genetic or environmental factors. However, anatomical studies of human brain development during the fetal period are surprisingly scarce and histology-based atlases have become available only recently. Diffusion tensor imaging (DTI measures water diffusion to delineate the underlying neural structures. The high contrasts derived from DTI can be used to establish the brain atlas. With DTI tractography, coherent neural structures, such as white matter tracts, can be three-dimensionally reconstructed. The primary eigenvector of the diffusion tensor can be further explored to characterize microstructures in the cerebral wall of the developmental brains. In this mini-review, the application of DTI in order to reveal the structures of developmental fetal brains has been reviewed in the above-mentioned aspects. The fetal brain DTI provides a unique insight for delineating the neural structures in both macroscopic and microscopic levels. The resultant DTI database will provide structural guidance for the developmental study of human fetal brains in basic neuroscience, and reference standards for diagnostic radiology of premature newborns.

  15. Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems

    Directory of Open Access Journals (Sweden)

    José Carlos Ortiz-Bayliss

    2018-01-01

    Full Text Available When solving constraint satisfaction problems (CSPs, it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differences among the orderings produced by some commonly used heuristics and the way bad first decisions affect the search cost. One of the most important findings of this work confirms the paramount importance of first decisions. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. We propose a simple method to improve early decisions of heuristics. By using it, performance of heuristics increases.

  16. Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems.

    Science.gov (United States)

    Ortiz-Bayliss, José Carlos; Amaya, Ivan; Conant-Pablos, Santiago Enrique; Terashima-Marín, Hugo

    2018-01-01

    When solving constraint satisfaction problems (CSPs), it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differences among the orderings produced by some commonly used heuristics and the way bad first decisions affect the search cost. One of the most important findings of this work confirms the paramount importance of first decisions. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. We propose a simple method to improve early decisions of heuristics. By using it, performance of heuristics increases.

  17. IRFK2D: a computer program for simulating intrinsic random functions of order k

    Science.gov (United States)

    Pardo-Igúzquiza, Eulogio; Dowd, Peter A.

    2003-07-01

    IRFK2D is an ANSI Fortran-77 program that generates realizations of an intrinsic function of order k (with k equal to 0, 1 or 2) with a permissible polynomial generalized covariance model. The realizations may be non-conditional or conditioned to the experimental data. The turning bands method is used to generate realizations in 2D and 3D from simulations of an intrinsic random function of order k along lines that span the 2D or 3D space. The program generates two output files, the first containing the simulated values and the second containing the theoretical generalized variogram for different directions together with the theoretical model. The experimental variogram is calculated from the simulated values while the theoretical variogram is the specified generalized covariance model. The generalized variogram is used to assess the quality of the simulation as measured by the extent to which the generalized covariance is reproduced by the simulation. The examples given in this paper indicate that IRFK2D is an efficient implementation of the methodology.

  18. Electrocardiogram ST-Segment Morphology Delineation Method Using Orthogonal Transformations.

    Directory of Open Access Journals (Sweden)

    Miha Amon

    Full Text Available Differentiation between ischaemic and non-ischaemic transient ST segment events of long term ambulatory electrocardiograms is a persisting weakness in present ischaemia detection systems. Traditional ST segment level measuring is not a sufficiently precise technique due to the single point of measurement and severe noise which is often present. We developed a robust noise resistant orthogonal-transformation based delineation method, which allows tracing the shape of transient ST segment morphology changes from the entire ST segment in terms of diagnostic and morphologic feature-vector time series, and also allows further analysis. For these purposes, we developed a new Legendre Polynomials based Transformation (LPT of ST segment. Its basis functions have similar shapes to typical transient changes of ST segment morphology categories during myocardial ischaemia (level, slope and scooping, thus providing direct insight into the types of time domain morphology changes through the LPT feature-vector space. We also generated new Karhunen and Lo ève Transformation (KLT ST segment basis functions using a robust covariance matrix constructed from the ST segment pattern vectors derived from the Long Term ST Database (LTST DB. As for the delineation of significant transient ischaemic and non-ischaemic ST segment episodes, we present a study on the representation of transient ST segment morphology categories, and an evaluation study on the classification power of the KLT- and LPT-based feature vectors to classify between ischaemic and non-ischaemic ST segment episodes of the LTST DB. Classification accuracy using the KLT and LPT feature vectors was 90% and 82%, respectively, when using the k-Nearest Neighbors (k = 3 classifier and 10-fold cross-validation. New sets of feature-vector time series for both transformations were derived for the records of the LTST DB which is freely available on the PhysioNet website and were contributed to the LTST DB. The

  19. Sequential Versus Simultaneous Market Delineation: The Relevant Antitrust Market for Salmon

    DEFF Research Database (Denmark)

    Haldrup, Niels; Peter, Møllgaard

    Delineation of the relevant market forms a pivotal part of most antitrust cases. The standard approach is sequential. First the product market is delineated, then the geographical market is defined. Demand andsupply substitution in both the product dimension and the geographical dimension will no...... and geographical markets. Using a unique data set for prices of Norwegian and Scottish salmon, we propose a methodology for simultaneous market delineation and we demonstrate that compared to a sequential approach conclusions will be reversed.......Delineation of the relevant market forms a pivotal part of most antitrust cases. The standard approach is sequential. First the product market is delineated, then the geographical market is defined. Demand andsupply substitution in both the product dimension and the geographical dimension...

  20. Assessment and remedy strategy for year 2000 (Y2K) problems in HANARO

    International Nuclear Information System (INIS)

    Kim, Y. K.; Jung, H. S.; Lee, B. J.; Choi, Y. S.

    1999-06-01

    This report is intended to address the Y2K assessment activities, which is required to evaluate the Y2K compliance for digital computers and microprocessor-based digital equipment currently used in HANARO. The Y2K assessment has been carried out and it indicates that only the radiation monitoring computer system was identified as a non-compliant products. An upgrades to the existing system have been completed by KAERI's own techniques. Through validation and commissioning, the upgraded system proved to be satisfactory and it is now in test operation. As for the programmable controller system, although it has been verified Y2K-compliant, considering its importance in the reactor power control, on-site Y2K test was performed and its compliance was certified. Under the inspection by regulatory body, it has been acknowledged by the integral Y2K simulation test that HANARO have successfully completed the Y2K remediation. A contingency planning was set up to deal with an unexpected situation that may occur at the specific dates and time relative to the Y2K problems. (author). 6 refs., 6 tabs

  1. The geometry of higher-order Lagrange spaces applications to mechanics and physics

    CERN Document Server

    Miron, Radu

    1997-01-01

    This monograph is devoted to the problem of the geometrizing of Lagrangians which depend on higher-order accelerations It presents a construction of the geometry of the total space of the bundle of the accelerations of order k>=1 A geometrical study of the notion of the higher-order Lagrange space is conducted, and the old problem of prolongation of Riemannian spaces to k-osculator manifolds is solved Also, the geometrical ground for variational calculus on the integral of actions involving higher-order Lagrangians is dealt with Applications to higher-order analytical mechanics and theoretical physics are included as well Audience This volume will be of interest to scientists whose work involves differential geometry, mechanics of particles and systems, calculus of variation and optimal control, optimization, optics, electromagnetic theory, and biology

  2. Diversity Controlling Genetic Algorithm for Order Acceptance and Scheduling Problem

    Directory of Open Access Journals (Sweden)

    Cheng Chen

    2014-01-01

    Full Text Available Selection and scheduling are an important topic in production systems. To tackle the order acceptance and scheduling problem on a single machine with release dates, tardiness penalty, and sequence-dependent setup times, in this paper a diversity controlling genetic algorithm (DCGA is proposed, in which a diversified population is maintained during the whole search process through survival selection considering both the fitness and the diversity of individuals. To measure the similarity between individuals, a modified Hamming distance without considering the unaccepted orders in the chromosome is adopted. The proposed DCGA was validated on 1500 benchmark instances with up to 100 orders. Compared with the state-of-the-art algorithms, the experimental results show that DCGA improves the solution quality obtained significantly, in terms of the deviation from upper bound.

  3. M-Adapting Low Order Mimetic Finite Differences for Dielectric Interface Problems

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Duncan A. [Oregon State Univ., Corvallis, OR (United States); Gyrya, Vitaliy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Manzini, Gianmarco [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-07

    We consider a problem of reducing numerical dispersion for electromagnetic wave in the domain with two materials separated by a at interface in 2D with a factor of two di erence in wave speed. The computational mesh in the homogeneous parts of the domain away from the interface consists of square elements. Here the method construction is based on m-adaptation construction in homogeneous domain that leads to fourth-order numerical dispersion (vs. second order in non-optimized method). The size of the elements in two domains also di ers by a factor of two, so as to preserve the same value of Courant number in each. Near the interface where two meshes merge the mesh with larger elements consists of degenerate pentagons. We demonstrate that prior to m-adaptation the accuracy of the method falls from second to rst due to breaking of symmetry in the mesh. Next we develop m-adaptation framework for the interface region and devise an optimization criteria. We prove that for the interface problem m-adaptation cannot produce increase in method accuracy. This is in contrast to homogeneous medium where m-adaptation can increase accuracy by two orders.

  4. Boundary-value problems for first and second order functional differential inclusions

    Directory of Open Access Journals (Sweden)

    Shihuang Hong

    2003-03-01

    Full Text Available This paper presents sufficient conditions for the existence of solutions to boundary-value problems of first and second order multi-valued differential equations in Banach spaces. Our results obtained using fixed point theorems, and lead to new existence principles.

  5. An Adaptive Pseudospectral Method for Fractional Order Boundary Value Problems

    Directory of Open Access Journals (Sweden)

    Mohammad Maleki

    2012-01-01

    Full Text Available An adaptive pseudospectral method is presented for solving a class of multiterm fractional boundary value problems (FBVP which involve Caputo-type fractional derivatives. The multiterm FBVP is first converted into a singular Volterra integrodifferential equation (SVIDE. By dividing the interval of the problem to subintervals, the unknown function is approximated using a piecewise interpolation polynomial with unknown coefficients which is based on shifted Legendre-Gauss (ShLG collocation points. Then the problem is reduced to a system of algebraic equations, thus greatly simplifying the problem. Further, some additional conditions are considered to maintain the continuity of the approximate solution and its derivatives at the interface of subintervals. In order to convert the singular integrals of SVIDE into nonsingular ones, integration by parts is utilized. In the method developed in this paper, the accuracy can be improved either by increasing the number of subintervals or by increasing the degree of the polynomial on each subinterval. Using several examples including Bagley-Torvik equation the proposed method is shown to be efficient and accurate.

  6. m-POINT BOUNDARY VALUE PROBLEM FOR SECOND ORDER IMPULSIVE DIFFERENTIAL EQUATION AT RESONANCE

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    In his paper,we obtain a general theorem concerning the existence of solutions to an m-point boundary value problem for the second-order differential equation with impulses.Moreover,the result can also be applied to study the usual m-point boundary value problem at resonance without impulses.

  7. Numerical Analysis of Forth-Order Boundary Value Problems in Fluid Mechanics and Mathematics

    DEFF Research Database (Denmark)

    Hosseinzadeh, E.; Barari, Amin; Fouladi, F.

    2011-01-01

    In this paper He's variational iteration method is used to solve some examples of linear and non-linear forth-order boundary value problems. The first problem compared with homotopy analysis method solution and the other ones with the exact solution. The results show the high accuracy and speed o...

  8. Numerical analysis of fourth-order boundary value problems in fluid mechanics and mathematics

    DEFF Research Database (Denmark)

    Hosseinzadeh, Elham; Barari, Amin; Fouladi, Fama

    2010-01-01

    In this paper He's variational iteration method is used to solve some examples of linear and non-linear forth-order boundary value problems. The first problem compared with homotopy analysis method solution and the other ones with the exact solution. The results show the high accuracy and speed o...

  9. Comparison of manual and semi-automated delineation of regions of interest for radioligand PET imaging analysis

    International Nuclear Information System (INIS)

    Chow, Tiffany W; Verhoeff, Nicolaas PLG; Takeshita, Shinichiro; Honjo, Kie; Pataky, Christina E; St Jacques, Peggy L; Kusano, Maggie L; Caldwell, Curtis B; Ramirez, Joel; Black, Sandra

    2007-01-01

    As imaging centers produce higher resolution research scans, the number of man-hours required to process regional data has become a major concern. Comparison of automated vs. manual methodology has not been reported for functional imaging. We explored validation of using automation to delineate regions of interest on positron emission tomography (PET) scans. The purpose of this study was to ascertain improvements in image processing time and reproducibility of a semi-automated brain region extraction (SABRE) method over manual delineation of regions of interest (ROIs). We compared 2 sets of partial volume corrected serotonin 1a receptor binding potentials (BPs) resulting from manual vs. semi-automated methods. BPs were obtained from subjects meeting consensus criteria for frontotemporal degeneration and from age- and gender-matched healthy controls. Two trained raters provided each set of data to conduct comparisons of inter-rater mean image processing time, rank order of BPs for 9 PET scans, intra- and inter-rater intraclass correlation coefficients (ICC), repeatability coefficients (RC), percentages of the average parameter value (RM%), and effect sizes of either method. SABRE saved approximately 3 hours of processing time per PET subject over manual delineation (p < .001). Quality of the SABRE BP results was preserved relative to the rank order of subjects by manual methods. Intra- and inter-rater ICC were high (>0.8) for both methods. RC and RM% were lower for the manual method across all ROIs, indicating less intra-rater variance across PET subjects' BPs. SABRE demonstrated significant time savings and no significant difference in reproducibility over manual methods, justifying the use of SABRE in serotonin 1a receptor radioligand PET imaging analysis. This implies that semi-automated ROI delineation is a valid methodology for future PET imaging analysis

  10. Recommendations for the delineation of organs at risk in ENT radiotherapy; Recommandations de delineation des organes a risque en radiotherapie ORL

    Energy Technology Data Exchange (ETDEWEB)

    Ali, D.; Halimi, P.; Berges, O.; Deberne, M.; Botti, M.; Giraud, P. [Hopital europeen Georges-Pompidou, Paris (France); Servagi-Vernat, S. [CHUjean-Minjoz, Besancon (France)

    2011-10-15

    Based on a literature survey, the authors propose recommendations for the delineation of the pharyngeal constrictor muscles, inner ear, larynx, buccal cavity, and temporomandibular joint. These recommendations of delineation of organs at risk are related to the functional anatomy of the considered structures, and correspond to volumes used in published surveys on dose-volume toxicity. They are simple and reproducible. Short communication

  11. Interobserver delineation variation in lung tumour stereotacticbody radiotherapy

    DEFF Research Database (Denmark)

    Persson, G. F.; Nygaard, D. E.; Hollensen, Christian

    2012-01-01

    the interobserver delineation variation for stereotactic body radiotherapy (SBRT) of peripheral lung tumours using a cross-sectional study design. Methods 22 consecutive patients with 26 tumours were included. Positron emission tomography/CT scans were acquired for planning of SBRT. Three oncologists and three......-sectional analysis of delineation variation for peripheral lung tumours referred for SBRT, establishing the evidence that interobserver variation is very small for these tumours....

  12. Delineation of gravel-bed clusters via factorial kriging

    Science.gov (United States)

    Wu, Fu-Chun; Wang, Chi-Kuei; Huang, Guo-Hao

    2018-05-01

    Gravel-bed clusters are the most prevalent microforms that affect local flows and sediment transport. A growing consensus is that the practice of cluster delineation should be based primarily on bed topography rather than grain sizes. Here we present a novel approach for cluster delineation using patch-scale high-resolution digital elevation models (DEMs). We use a geostatistical interpolation method, i.e., factorial kriging, to decompose the short- and long-range (grain- and microform-scale) DEMs. The required parameters are determined directly from the scales of the nested variograms. The short-range DEM exhibits a flat bed topography, yet individual grains are sharply outlined, making the short-range DEM a useful aid for grain segmentation. The long-range DEM exhibits a smoother topography than the original full DEM, yet groupings of particles emerge as small-scale bedforms, making the contour percentile levels of the long-range DEM a useful tool for cluster identification. Individual clusters are delineated using the segmented grains and identified clusters via a range of contour percentile levels. Our results reveal that the density and total area of delineated clusters decrease with increasing contour percentile level, while the mean grain size of clusters and average size of anchor clast (i.e., the largest particle in a cluster) increase with the contour percentile level. These results support the interpretation that larger particles group as clusters and protrude higher above the bed than other smaller grains. A striking feature of the delineated clusters is that anchor clasts are invariably greater than the D90 of the grain sizes even though a threshold anchor size was not adopted herein. The average areal fractal dimensions (Hausdorff-Besicovich dimensions of the projected areas) of individual clusters, however, demonstrate that clusters delineated with different contour percentile levels exhibit similar planform morphologies. Comparisons with a

  13. Infinitely many solutions for a fourth-order boundary-value problem

    Directory of Open Access Journals (Sweden)

    Seyyed Mohsen Khalkhali

    2012-09-01

    Full Text Available In this article we consider the existence of infinitely many solutions to the fourth-order boundary-value problem $$displaylines{ u^{iv}+alpha u''+eta(x u=lambda f(x,u+h(u,quad xin]0,1[cr u(0=u(1=0,cr u''(0=u''(1=0,. }$$ Our approach is based on variational methods and critical point theory.

  14. Reduction of respiratory ghosting motion artifacts in conventional two-dimensional multi-slice Cartesian turbo spin-echo: which k-space filling order is the best?

    Science.gov (United States)

    Inoue, Yuuji; Yoneyama, Masami; Nakamura, Masanobu; Takemura, Atsushi

    2018-06-01

    The two-dimensional Cartesian turbo spin-echo (TSE) sequence is widely used in routine clinical studies, but it is sensitive to respiratory motion. We investigated the k-space orders in Cartesian TSE that can effectively reduce motion artifacts. The purpose of this study was to demonstrate the relationship between k-space order and degree of motion artifacts using a moving phantom. We compared the degree of motion artifacts between linear and asymmetric k-space orders. The actual spacing of ghost artifacts in the asymmetric order was doubled compared with that in the linear order in the free-breathing situation. The asymmetric order clearly showed less sensitivity to incomplete breath-hold at the latter half of the imaging period. Because of the actual number of partitions of the k-space and the temporal filling order, the asymmetric k-space order of Cartesian TSE was superior to the linear k-space order for reduction of ghosting motion artifacts.

  15. A High Performance Computing Approach to Tree Cover Delineation in 1-m NAIP Imagery Using a Probabilistic Learning Framework

    Science.gov (United States)

    Basu, Saikat; Ganguly, Sangram; Michaelis, Andrew; Votava, Petr; Roy, Anshuman; Mukhopadhyay, Supratik; Nemani, Ramakrishna

    2015-01-01

    Tree cover delineation is a useful instrument in deriving Above Ground Biomass (AGB) density estimates from Very High Resolution (VHR) airborne imagery data. Numerous algorithms have been designed to address this problem, but most of them do not scale to these datasets, which are of the order of terabytes. In this paper, we present a semi-automated probabilistic framework for the segmentation and classification of 1-m National Agriculture Imagery Program (NAIP) for tree-cover delineation for the whole of Continental United States, using a High Performance Computing Architecture. Classification is performed using a multi-layer Feedforward Backpropagation Neural Network and segmentation is performed using a Statistical Region Merging algorithm. The results from the classification and segmentation algorithms are then consolidated into a structured prediction framework using a discriminative undirected probabilistic graphical model based on Conditional Random Field, which helps in capturing the higher order contextual dependencies between neighboring pixels. Once the final probability maps are generated, the framework is updated and re-trained by relabeling misclassified image patches. This leads to a significant improvement in the true positive rates and reduction in false positive rates. The tree cover maps were generated for the whole state of California, spanning a total of 11,095 NAIP tiles covering a total geographical area of 163,696 sq. miles. The framework produced true positive rates of around 88% for fragmented forests and 74% for urban tree cover areas, with false positive rates lower than 2% for both landscapes. Comparative studies with the National Land Cover Data (NLCD) algorithm and the LiDAR canopy height model (CHM) showed the effectiveness of our framework for generating accurate high-resolution tree-cover maps.

  16. A High Performance Computing Approach to Tree Cover Delineation in 1-m NAIP Imagery using a Probabilistic Learning Framework

    Science.gov (United States)

    Basu, S.; Ganguly, S.; Michaelis, A.; Votava, P.; Roy, A.; Mukhopadhyay, S.; Nemani, R. R.

    2015-12-01

    Tree cover delineation is a useful instrument in deriving Above Ground Biomass (AGB) density estimates from Very High Resolution (VHR) airborne imagery data. Numerous algorithms have been designed to address this problem, but most of them do not scale to these datasets which are of the order of terabytes. In this paper, we present a semi-automated probabilistic framework for the segmentation and classification of 1-m National Agriculture Imagery Program (NAIP) for tree-cover delineation for the whole of Continental United States, using a High Performance Computing Architecture. Classification is performed using a multi-layer Feedforward Backpropagation Neural Network and segmentation is performed using a Statistical Region Merging algorithm. The results from the classification and segmentation algorithms are then consolidated into a structured prediction framework using a discriminative undirected probabilistic graphical model based on Conditional Random Field, which helps in capturing the higher order contextual dependencies between neighboring pixels. Once the final probability maps are generated, the framework is updated and re-trained by relabeling misclassified image patches. This leads to a significant improvement in the true positive rates and reduction in false positive rates. The tree cover maps were generated for the whole state of California, spanning a total of 11,095 NAIP tiles covering a total geographical area of 163,696 sq. miles. The framework produced true positive rates of around 88% for fragmented forests and 74% for urban tree cover areas, with false positive rates lower than 2% for both landscapes. Comparative studies with the National Land Cover Data (NLCD) algorithm and the LiDAR canopy height model (CHM) showed the effectiveness of our framework for generating accurate high-resolution tree-cover maps.

  17. Analisa Sistem Ordering Material Plastik pada PT XYZ dengan menggunakan Metode Kepner-Tregoe Problem Solving

    Directory of Open Access Journals (Sweden)

    Jonny Lin

    2015-05-01

    Full Text Available PT XYZ has faced a problem related to its plastik material ordering system in which its quantity purchase order calculation result was so different with its manual calculation that its material logictic staff was needed to make a proper correction. Therefore, this research was taken in order to help the staff to analyze its root cause so that the proper improvement could be taken and the quantity purchase order calculation will be equal to its manual calculation. By deploying Kepner-Tregoe problem solving, the staff found that the difference was due to miss-managed algorthim of the system because the quantity purchase order that is still open was not considered in the calculation and after proper improvement was taken, then the quantity purchase order calculation is equal to the manual calculation.

  18. Monomiality principle, Sheffer-type polynomials and the normal ordering problem

    International Nuclear Information System (INIS)

    Penson, K A; Blasiak, P; Dattoli, G; Duchamp, G H E; Horzela, A; Solomon, A I

    2006-01-01

    We solve the boson normal ordering problem for (q(a † )a + v(a † )) n with arbitrary functions q(x) and v(x) and integer n, where a and a † are boson annihilation and creation operators, satisfying [a, a † ] = 1. This consequently provides the solution for the exponential e λ(q(a † )a+v(a † )) generalizing the shift operator. In the course of these considerations we define and explore the monomiality principle and find its representations. We exploit the properties of Sheffer-type polynomials which constitute the inherent structure of this problem. In the end we give some examples illustrating the utility of the method and point out the relation to combinatorial structures

  19. Analisa Sistem Ordering Material Plastik pada PT XYZ dengan Kepner-Tregoe Problem Solving

    OpenAIRE

    Jonny

    2015-01-01

    PT XYZ has faced a problem related to its plastik material ordering system in which its quantity purchase order calculation result was so different with its manual calculation that its material logictic staff was needed to make a proper correction. Therefore, this research was taken in order to help the staff to analyze its root cause so that the proper improvement could be taken and the quantity purchase order calculation will be equal to its manual calculation. By deploying Kepner-Tregoe pr...

  20. Problem-Based Learning in the Earth and Space Science Classroom, K-12

    Science.gov (United States)

    McConnell, Tom J.; Parker, Joyce; Eberhardt, Janet

    2017-01-01

    If you've ever asked yourself whether problem-based learning (PBL) can bring new life to both your teaching and your students' learning, here's your answer: Yes. This all-in-one guide will help you engage your students in scenarios that represent real-world science in all its messy, thought-provoking glory. The scenarios will prompt K-12 students…

  1. A multi-supplier sourcing problem with a preference ordering of suppliers

    NARCIS (Netherlands)

    Honhon, D.B.L.P.; Gaur, V.; Seshadri, S.

    2012-01-01

    We study a sourcing problem faced by a firm that seeks to procure a product or a component from a pool of alternative suppliers. The firm has a preference ordering of the suppliers based on factors such as their past performance, quality, service, geographical location, and financial strength, which

  2. A novel algorithm for delineating wetland depressions and ...

    Science.gov (United States)

    In traditional watershed delineation and topographic modeling, surface depressions are generally treated as spurious features and simply removed from a digital elevation model (DEM) to enforce flow continuity of water across the topographic surface to the watershed outlets. In reality, however, many depressions in the DEM are actual wetland landscape features that are seldom fully filled with water. For instance, wetland depressions in the Prairie Pothole Region (PPR) are seasonally to permanently flooded wetlands characterized by nested hierarchical structures with dynamic filling- spilling-merging surface-water hydrological processes. The objectives of this study were to delineate hierarchical wetland catchments and model their hydrologic connectivity using high-resolution LiDAR data and aerial imagery. We proposed a novel algorithm delineate the hierarchical wetland catchments and characterize their geometric and topological properties. Potential hydrologic connectivity between wetlands and streams were simulated using the least-cost path algorithm. The resulting flow network delineated putative temporary or seasonal flow paths connecting wetland depressions to each other or to the river network at scales finer than available through the National Hydrography Dataset. The results demonstrated that our proposed framework is promising for improving overland flow modeling and hydrologic connectivity analysis. Presentation at AWRA Spring Specialty Conference in Sn

  3. Delineating SPTAN1 associated phenotypes

    DEFF Research Database (Denmark)

    Syrbe, Steffen; Harms, Frederike L; Parrini, Elena

    2017-01-01

    De novo in-frame deletions and duplications in the SPTAN1 gene, encoding the non-erythrocyte αII spectrin, have been associated with severe West syndrome with hypomyelination and pontocerebellar atrophy. We aimed at comprehensively delineating the phenotypic spectrum associated with SPTAN1 mutati...

  4. Delineation of geological facies from poorly differentiated data

    Energy Technology Data Exchange (ETDEWEB)

    Wohlberg, Brendt [Los Alamos National Laboratory; Tartakovsky, Daniel [UCSC

    2008-01-01

    The ability to delineate geologic facies and to estima.te their properties from sparse data is essential for modeling physical and biochemical processes occurring in the 'ubsurface. If such data are poorly differentiated, this challcnrring task is complicated further by the absence of a clear distinction between different hydrofacies even at locations where data. are available. vVe consider three alt mative approaches for analysis of poorly differentiated data: a k-means clU!:iterinrr algorithm, an expectation-maximization algorithm, and a minimum-variance algorithm. Two distinct synthetically generated geological settings are used to r:tnalyze the ability of these algorithmti to as ign accurately the membership of such data in a given geologic facies. On average, the minimum-variance algorithm provides a more robust p rformance than its two counterparts and when combined with a nearest-neighbor algorithm, it also yields the most accurate reconstruction of the boundaries between the facies.

  5. Automatic tumour volume delineation in respiratory-gated PET images

    International Nuclear Information System (INIS)

    Gubbi, Jayavardhana; Palaniswami, Marimuthu; Kanakatte, Aparna; Mani, Nallasamy; Kron, Tomas; Binns, David; Srinivasan, Bala

    2011-01-01

    Positron emission tomography (PET) is a state-of-the-art functional imaging technique used in the accurate detection of cancer. The main problem with the tumours present in the lungs is that they are non-stationary during each respiratory cycle. Tumours in the lungs can get displaced up to 2.5 cm during respiration. Accurate detection of the tumour enables avoiding the addition of extra margin around the tumour that is usually used during radiotherapy treatment planning. This paper presents a novel method to detect and track tumour in respiratory-gated PET images. The approach followed to achieve this task is to automatically delineate the tumour from the first frame using support vector machines. The resulting volume and position information from the first frame is used in tracking its motion in the subsequent frames with the help of level set (LS) deformable model. An excellent accuracy of 97% is obtained using wavelets and support vector machines. The volume calculated as a result of the machine learning (ML) stage is used as a constraint for deformable models and the tumour is tracked in the remaining seven phases of the respiratory cycle. As a result, the complete information about tumour movement during each respiratory cycle is available in relatively short time. The combination of the LS and ML approach accurately delineated the tumour volume from all frames, thereby providing a scope of using PET images towards planning an accurate and effective radiotherapy treatment for lung cancer.

  6. A boundary value problem for a third order hyperbolic equation with degeneration of order inside the domain

    Directory of Open Access Journals (Sweden)

    Ruzanna Kh. Makaova

    2017-12-01

    Full Text Available In this paper we study the boundary value problem for a degenerating third order equation of hyperbolic type in a mixed domain. The equation under consideration in the positive part of the domain coincides with the Hallaire equation, which is a pseudoparabolic type equation. Moreover, in the negative part of the domain it coincides with a degenerating hyperbolic equation of the first kind, the particular case of the Bitsadze–Lykov equation. The existence and uniqueness theorem for the solution is proved. The uniqueness of the solution to the problem is proved with the Tricomi method. Using the functional relationships of the positive and negative parts of the domain on the degeneration line, we arrive at the convolution type Volterra integral equation of the 2nd kind with respect to the desired solution by a derivative trace. With the Laplace transform method, we obtain the solution of the integral equation in its explicit form. At last, the solution to the problem under study is written out explicitly as the solution of the second boundary-value problem in the positive part of the domain for the Hallaire equation and as the solution to the Cauchy problem in the negative part of the domain for a degenerate hyperbolic equation of the first kind.

  7. Uniqueness in some higher order elliptic boundary value problems in n dimensional domains

    Directory of Open Access Journals (Sweden)

    C.-P. Danet

    2011-07-01

    Full Text Available We develop maximum principles for several P functions which are defined on solutions to equations of fourth and sixth order (including a equation which arises in plate theory and bending of cylindrical shells. As a consequence, we obtain uniqueness results for fourth and sixth order boundary value problems in arbitrary n dimensional domains.

  8. Development of Problem Sets for K-12 and Engineering on Pharmaceutical Particulate Systems

    Science.gov (United States)

    Savelski, Mariano J.; Slater, C. Stewart; Del Vecchio, Christopher A.; Kosteleski, Adrian J.; Wilson, Sarah A.

    2010-01-01

    Educational problem sets have been developed on structured organic particulate systems (SOPS) used in pharmaceutical technology. The sets present topics such as particle properties and powder flow and can be integrated into K-12 and college-level curricula. The materials educate students in specific areas of pharmaceutical particulate processing,…

  9. MRI target delineation may reduce long-term toxicity after prostate radiotherapy.

    Science.gov (United States)

    Sander, Lotte; Langkilde, Niels Christian; Holmberg, Mats; Carl, Jesper

    2014-06-01

    Aiming for minimal toxicity after radical prostate cancer (PC) radiotherapy (RT), magnetic resonance imaging (MRI) target delineation could be a possible benefit knowing that clinical target volumes (CTV) are up to 30% smaller, when CTV delineation on MRI is compared to standard computed tomography (CT). This study compares long-term toxicity using CT or MRI delineation before PC RT. Urinary and rectal toxicity assessments 36 months after image-guided RT (78 Gy) using CTC-AE scores in two groups of PC patients. Peak symptom score values were registered. One group of patients (n=72) had standard CT target delineation and gold markers as fiducials. Another group of patients (n=73) had MRI target delineation and a nickel-titanium stent as fiducial. At 36 months no difference in overall survival (92% in both groups, p=0.29) or in PSA-relapse free survival was found between the groups (MRI=89% and CT=94%, p=0.67). A significantly smaller CTV was found in the MRI group (p=0.02). Urinary retention and frequency were significantly reduced in the MRI group (p=0.03 in the matter of both). The overall urinary and rectal toxicity did not differ between the two groups. MRI delineation leads to a significantly reduced CTV. Significantly lower urinary frequency and urinary retention toxicity scores were observed following MRI delineation. The study did not find significant differences in overall urinary or rectal toxicity between the two groups. PSA-relapse survival did not differ between the two groups at 36 months.

  10. Near-census Delineation of Laterally Organized Geomorphic Zones and Associated Sub-width Fluvial Landforms

    Science.gov (United States)

    Pasternack, G. B.; Hopkins, C.

    2017-12-01

    A river channel and its associated riparian corridor exhibit a pattern of nested, geomorphically imprinted, lateral inundation zones (IZs). Each zone plays a key role in fluvial geomorphic processes and ecological functions. Within each zone, distinct landforms (aka geomorphic or morphological units, MUs) reside at the 0.1-10 channel width scale. These features are basic units linking river corridor morphology with local ecosystem services. Objective, automated delineation of nested inundation zones and morphological units remains a significant scientific challenge. This study describes and demonstrates new, objective methods for solving this problem, using the 35-km alluvial lower Yuba River as a testbed. A detrended, high-resolution digital elevation model constructed from near-census topographic and bathymetric data was produced and used in a hypsograph analysis, a commonly used method in oceanographic studies capable of identifying slope breaks at IZ transitions. Geomorphic interpretation mindful of the river's setting was required to properly describe each IZ identified by the hypsograph analysis. Then, a 2D hydrodynamic model was used to determine what flow yields the wetted area that most closely matches each IZ domain. The model also provided meter-scale rasters of depth and velocity useful for MU mapping. Even though MUs are discharge-independent landforms, they can be revealed by analyzing their overlying hydraulics at low flows. Baseflow depth and velocity rasters are used along with a hydraulic landform classification system to quantitatively delineate in-channel bed MU types. In-channel bar and off-channel flood and valley MUs are delineated using a combination of hydraulic and geomorphic indicators, such as depth and velocity rasters for different discharges, topographic contours, NAIP imagery, and a raster of vegetation. The ability to objectively delineate inundation zones and morphological units in tandem allows for better informed river management

  11. The Y2K Problem: Will It Just Be Another New Year's Eve?

    Science.gov (United States)

    Iwanowski, Jay

    1998-01-01

    Potential problems for college and university computing functions posed by arrival of the year 2000 (Y2K) are discussed, including arithmetic calculations and sorting functions based on two-digit year dates, embedding of two-digit dates in archival data, system coordination for data exchange, unique number generation, and leap year calculations. A…

  12. Multi-level nonlinear diffusion acceleration method for multigroup transport k-Eigenvalue problems

    International Nuclear Information System (INIS)

    Anistratov, Dmitriy Y.

    2011-01-01

    The nonlinear diffusion acceleration (NDA) method is an efficient and flexible transport iterative scheme for solving reactor-physics problems. This paper presents a fast iterative algorithm for solving multigroup neutron transport eigenvalue problems in 1D slab geometry. The proposed method is defined by a multi-level system of equations that includes multigroup and effective one-group low-order NDA equations. The Eigenvalue is evaluated in the exact projected solution space of smallest dimensionality, namely, by solving the effective one- group eigenvalue transport problem. Numerical results that illustrate performance of the new algorithm are demonstrated. (author)

  13. A comparison of high-order polynomial and wave-based methods for Helmholtz problems

    Science.gov (United States)

    Lieu, Alice; Gabard, Gwénaël; Bériot, Hadrien

    2016-09-01

    The application of computational modelling to wave propagation problems is hindered by the dispersion error introduced by the discretisation. Two common strategies to address this issue are to use high-order polynomial shape functions (e.g. hp-FEM), or to use physics-based, or Trefftz, methods where the shape functions are local solutions of the problem (typically plane waves). Both strategies have been actively developed over the past decades and both have demonstrated their benefits compared to conventional finite-element methods, but they have yet to be compared. In this paper a high-order polynomial method (p-FEM with Lobatto polynomials) and the wave-based discontinuous Galerkin method are compared for two-dimensional Helmholtz problems. A number of different benchmark problems are used to perform a detailed and systematic assessment of the relative merits of these two methods in terms of interpolation properties, performance and conditioning. It is generally assumed that a wave-based method naturally provides better accuracy compared to polynomial methods since the plane waves or Bessel functions used in these methods are exact solutions of the Helmholtz equation. Results indicate that this expectation does not necessarily translate into a clear benefit, and that the differences in performance, accuracy and conditioning are more nuanced than generally assumed. The high-order polynomial method can in fact deliver comparable, and in some cases superior, performance compared to the wave-based DGM. In addition to benchmarking the intrinsic computational performance of these methods, a number of practical issues associated with realistic applications are also discussed.

  14. Variational Iteration Method for Fifth-Order Boundary Value Problems Using He's Polynomials

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam Noor

    2008-01-01

    Full Text Available We apply the variational iteration method using He's polynomials (VIMHP for solving the fifth-order boundary value problems. The proposed method is an elegant combination of variational iteration and the homotopy perturbation methods and is mainly due to Ghorbani (2007. The suggested algorithm is quite efficient and is practically well suited for use in these problems. The proposed iterative scheme finds the solution without any discritization, linearization, or restrictive assumptions. Several examples are given to verify the reliability and efficiency of the method. The fact that the proposed technique solves nonlinear problems without using Adomian's polynomials can be considered as a clear advantage of this algorithm over the decomposition method.

  15. K-Minimax Stochastic Programming Problems

    Science.gov (United States)

    Nedeva, C.

    2007-10-01

    The purpose of this paper is a discussion of a numerical procedure based on the simplex method for stochastic optimization problems with partially known distribution functions. The convergence of this procedure is proved by the condition on dual problems.

  16. The Application of the Weighted k-Partite Graph Problem to the Multiple Alignment for Metabolic Pathways.

    Science.gov (United States)

    Chen, Wenbin; Hendrix, William; Samatova, Nagiza F

    2017-12-01

    The problem of aligning multiple metabolic pathways is one of very challenging problems in computational biology. A metabolic pathway consists of three types of entities: reactions, compounds, and enzymes. Based on similarities between enzymes, Tohsato et al. gave an algorithm for aligning multiple metabolic pathways. However, the algorithm given by Tohsato et al. neglects the similarities among reactions, compounds, enzymes, and pathway topology. How to design algorithms for the alignment problem of multiple metabolic pathways based on the similarity of reactions, compounds, and enzymes? It is a difficult computational problem. In this article, we propose an algorithm for the problem of aligning multiple metabolic pathways based on the similarities among reactions, compounds, enzymes, and pathway topology. First, we compute a weight between each pair of like entities in different input pathways based on the entities' similarity score and topological structure using Ay et al.'s methods. We then construct a weighted k-partite graph for the reactions, compounds, and enzymes. We extract a mapping between these entities by solving the maximum-weighted k-partite matching problem by applying a novel heuristic algorithm. By analyzing the alignment results of multiple pathways in different organisms, we show that the alignments found by our algorithm correctly identify common subnetworks among multiple pathways.

  17. Peak-valley-peak pattern of histone modifications delineates active regulatory elements and their directionality

    DEFF Research Database (Denmark)

    Pundhir, Sachin; Bagger, Frederik Otzen; Lauridsen, Felicia Kathrine Bratt

    2016-01-01

    Formation of nucleosome free region (NFR) accompanied by specific histone modifications at flanking nucleosomes is an important prerequisite for enhancer and promoter activity. Due to this process, active regulatory elements often exhibit a distinct shape of histone signal in the form of a peak......-valley-peak (PVP) pattern. However, different features of PVP patterns and their robustness in predicting active regulatory elements have never been systematically analyzed. Here, we present PARE, a novel computational method that systematically analyzes the H3K4me1 or H3K4me3 PVP patterns to predict NFRs. We show...... four ENCODE cell lines and four hematopoietic differentiation stages, we identified several enhancers whose regulatory activity is stage specific and correlates positively with the expression of proximal genes in a particular stage. In conclusion, our results demonstrate that PVP patterns delineate...

  18. Semi-automatic delineation using weighted CT-MRI registered images for radiotherapy of nasopharyngeal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Fitton, I. [European Georges Pompidou Hospital, Department of Radiology, 20 rue Leblanc, 75015, Paris (France); Cornelissen, S. A. P. [Image Sciences Institute, UMC, Department of Radiology, P.O. Box 85500, 3508 GA Utrecht (Netherlands); Duppen, J. C.; Rasch, C. R. N.; Herk, M. van [The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Radiotherapy, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Steenbakkers, R. J. H. M. [University Medical Center Groningen, Department of Radiation Oncology, Hanzeplein 1, 9713 GZ Groningen (Netherlands); Peeters, S. T. H. [UZ Gasthuisberg, Herestraat 49, 3000 Leuven, Belgique (Belgium); Hoebers, F. J. P. [Maastricht University Medical Center, Department of Radiation Oncology (MAASTRO clinic), GROW School for Oncology and Development Biology Maastricht, 6229 ET Maastricht (Netherlands); Kaanders, J. H. A. M. [UMC St-Radboud, Department of Radiotherapy, Geert Grooteplein 32, 6525 GA Nijmegen (Netherlands); Nowak, P. J. C. M. [ERASMUS University Medical Center, Department of Radiation Oncology,Groene Hilledijk 301, 3075 EA Rotterdam (Netherlands)

    2011-08-15

    Purpose: To develop a delineation tool that refines physician-drawn contours of the gross tumor volume (GTV) in nasopharynx cancer, using combined pixel value information from x-ray computed tomography (CT) and magnetic resonance imaging (MRI) during delineation. Methods: Operator-guided delineation assisted by a so-called ''snake'' algorithm was applied on weighted CT-MRI registered images. The physician delineates a rough tumor contour that is continuously adjusted by the snake algorithm using the underlying image characteristics. The algorithm was evaluated on five nasopharyngeal cancer patients. Different linear weightings CT and MRI were tested as input for the snake algorithm and compared according to contrast and tumor to noise ratio (TNR). The semi-automatic delineation was compared with manual contouring by seven experienced radiation oncologists. Results: A good compromise for TNR and contrast was obtained by weighing CT twice as strong as MRI. The new algorithm did not notably reduce interobserver variability, it did however, reduce the average delineation time by 6 min per case. Conclusions: The authors developed a user-driven tool for delineation and correction based a snake algorithm and registered weighted CT image and MRI. The algorithm adds morphological information from CT during the delineation on MRI and accelerates the delineation task.

  19. Polyharmonic boundary value problems positivity preserving and nonlinear higher order elliptic equations in bounded domains

    CERN Document Server

    Gazzola, Filippo; Sweers, Guido

    2010-01-01

    This monograph covers higher order linear and nonlinear elliptic boundary value problems in bounded domains, mainly with the biharmonic or poly-harmonic operator as leading principal part. Underlying models and, in particular, the role of different boundary conditions are explained in detail. As for linear problems, after a brief summary of the existence theory and Lp and Schauder estimates, the focus is on positivity or - since, in contrast to second order equations, a general form of a comparison principle does not exist - on “near positivity.” The required kernel estimates are also presented in detail. As for nonlinear problems, several techniques well-known from second order equations cannot be utilized and have to be replaced by new and different methods. Subcritical, critical and supercritical nonlinearities are discussed and various existence and nonexistence results are proved. The interplay with the positivity topic from the first part is emphasized and, moreover, a far-reaching Gidas-Ni-Nirenbe...

  20. REVIEWS OF TOPICAL PROBLEMS: Order-disorder transformations and phase equilibria in strongly nonstoichiometric compounds

    Science.gov (United States)

    Gusev, Aleksandr I.

    2000-01-01

    Data on order-disorder phase transformations in strongly nonstoichiometric carbides and nitrides MXy (X=C, N) of Group IV and V transition metals at temperatures below 1300-1400 K are reviewed. The order-parameter functional method as applied to atomic and vacancy ordering in strongly nonstoichiometric MXy compounds and to phase equilibrium calculations for M-X systems is discussed. Phase diagram calculations for the Ti-C, Zr-C, Hf-C, V-C, Nb-C, Ta-C, Ti-N, and Ti-B-C systems (with the inclusion of the ordering of nonstoichiometric carbides and nitrides) and those for pseudobinary carbide M(1)C-M(2)C systems are presented. Heat capacity, electrical resistivity and magnetic susceptibility changes at reversible order-disorder phase transformations in nonstoichiometric carbides are considered.

  1. No-Go Theorem for k-Essence Dark Energy

    International Nuclear Information System (INIS)

    Bonvin, Camille; Caprini, Chiara; Durrer, Ruth

    2006-01-01

    We demonstrate that if k-essence can solve the coincidence problem and play the role of dark energy in the Universe, the fluctuations of the field have to propagate superluminally at some stage. We argue that this implies that successful k-essence models violate causality. It is not possible to define a time ordered succession of events in a Lorentz invariant way. Therefore, k-essence cannot arise as a low energy effective field theory of a causal, consistent high energy theory

  2. Analysis of the NEACRP PWR rod ejection benchmark problems with DIF3D-K

    International Nuclear Information System (INIS)

    Kim, M.H.

    1994-01-01

    Analyses of the NEACRP PWR rod ejection transient benchmark problems with the DIF3D-K nodal kinetics code are presented. The DIF3D-K results are shown to be in generally good agreement with results obtained using other codes, in particular reference results previously generated with the PANTHER code. The sensitivity of the transient results to the DIF3D-K input parameters (such as time step size, radial and axial node sizes, and the mesh structure employed for fuel pin heat conduction calculation) are evaluated and discussed. In addition, the potential in reducing computational effort by application of the improved quasistatic scheme (IQS) to these rod ejection transients, which involve very significant flux shape changes and thermal-hydraulic feedback is evaluated

  3. Coupling of structure to magnetic and superconducting orders in quasi-one-dimensional K2Cr3As3

    Science.gov (United States)

    Taddei, K. M.; Zheng, Q.; Sefat, A. S.; de la Cruz, C.

    2017-11-01

    Quasi-one-dimensional A2Cr3As3 (with A =K , Cs, Rb) is an intriguing new family of superconductors which exhibit many similar features to the cuprate and iron-based unconventional superconductor families. Yet, in contrast to these systems, no charge or magnetic ordering has been observed which could provide the electronic correlations presumed necessary for an unconventional superconducting pairing mechanism—an absence which defies predictions of first-principles models. We report the results of neutron scattering experiments on polycrystalline K2Cr3As3 (Tc˜7 K ) which probed the low-temperature dynamics near Tc. Neutron diffraction data evidence a subtle response of the nuclear lattice to the onset of superconductivity while inelastic scattering reveals a highly dispersive column of intensity at the commensurate wave vector q =(00 1/2 ) which loses intensity beneath Tc—indicative of short-range magnetic fluctuations. Using linear spin-wave theory, we model the observed scattering and suggest a possible structure to the short-range magnetic order. These observations suggest that K2Cr3As3 is in close proximity to a magnetic instability and that the incipient magnetic order both couples strongly to the lattice and competes with superconductivity, in direct analogy with the iron-based superconductors.

  4. The Significance of Land Cover Delineation on Soil Erosion Assessment.

    Science.gov (United States)

    Efthimiou, Nikolaos; Psomiadis, Emmanouil

    2018-04-25

    The study aims to evaluate the significance of land cover delineation on soil erosion assessment. To that end, RUSLE (Revised Universal Soil Loss Equation) was implemented at the Upper Acheloos River catchment, Western Central Greece, annually and multi-annually for the period 1965-92. The model estimates soil erosion as the linear product of six factors (R, K, LS, C, and P) considering the catchment's climatic, pedological, topographic, land cover, and anthropogenic characteristics, respectively. The C factor was estimated using six alternative land use delineations of different resolution, namely the CORINE Land Cover (CLC) project (2000, 2012 versions) (1:100,000), a land use map conducted by the Greek National Agricultural Research Foundation (NAGREF) (1:20,000), a land use map conducted by the Greek Payment and Control Agency for Guidance and Guarantee Community Aid (PCAGGCA) (1:5,000), and the Landsat 8 16-day Normalized Difference Vegetation Index (NDVI) dataset (30 m/pixel) (two approximations) based on remote sensing data (satellite image acquired on 07/09/2016) (1:40,000). Since all other factors remain unchanged per each RUSLE application, the differences among the yielded results are attributed to the C factor (thus the land cover pattern) variations. Validation was made considering the convergence between simulated (modeled) and observed sediment yield. The latter was estimated based on field measurements conducted by the Greek PPC (Public Power Corporation). The model performed best at both time scales using the Landsat 8 (Eq. 13) dataset, characterized by a detailed resolution and a satisfactory categorization, allowing the identification of the most susceptible to erosion areas.

  5. Dose due to 40K

    International Nuclear Information System (INIS)

    Escareno J, E.; Vega C, H. R.

    2011-10-01

    The dose due to 40 K has been estimated. Potassium is one of the most abundant elements in nature, being approximately 2% of the Earth's crust. Potassium has three isotopes 39 K, 40 K and 41 K, two are stable while 40 K is radioactive with a half life of 1.2x10 9 years; there is 0.0117% 40 K-to-K ratio. Potassium plays an important role in plants, animals and humans growth and reproduction. Due to the fact that K is an essential element for humans, 40 K is the most abundant radioisotope in human body. In order to keep good health conditions K must be intake at daily basis trough food and beverages, however when K in ingested above the requirements produce adverse health effects in persons with renal, cardiac and hypertension problems or suffering diabetes. In 89.3% 40 K decays to 40 C through β-decay, in 10.3% decays through electronic capture and emitting 1.46 MeV γ-ray. K is abundant in soil, construction materials, sand thus γ-rays produced during 40 K decay contribute to external dose. For K in the body practically all 40 K decaying energy is absorbed by the body; thus 40 K contributes to total dose in humans and it is important to evaluate its contribution. In this work a set of 40 K sources were prepared using different amounts of KCl salt, a γ-ray spectrometer with a NaI(Tl) was characterized to standardized the sources in order to evaluate the dose due to 40 K. Using thermoluminescent dosemeters the dose due to 40 K was measured and related to the amount of 40 K γ-ray activity. (Author)

  6. K-dron, its mathematical modeling and applications

    Directory of Open Access Journals (Sweden)

    Janusz Kapusta

    2016-01-01

    Full Text Available In this paper we present the definition of K-dron, new geometrical form discovered by Janusz Kapusta in 1985 in New York, its history and connection between geometry and symmetry of a cube. It is worth to emphasize that the authors have derived new formulae for the surface of K-dron using the Laplaceatransform in order to obtain the solution of the boundary-value problem for the partial differential equation describing the vibration of the string. The formula proved by us in this paper is clearer and understandable in view of this structure. The solution obtained in this paper describes in general manner the surface of K-dron and more general surfaces named by us n-K-drons. The formula for the surface of K-dron was derived by the method of Laplacea transform having clear geometrical and physical interpretation because it is presented in linear combination of the equation of planes with the coefficients of directions described by suitable combinations of Heavisides functions. Also wide range and different applications of K-dron are presented.[b]Słowa kluczowe[/b]: K-dron, Laplace’a transform, partial differential of string equation of vibration, initial-boundary value problems

  7. Aspen Delineation - Inyo National Forest [ds366

    Data.gov (United States)

    California Natural Resource Agency — The database represents delineations of known aspen stands where aspen assessments were collected in the Inyo National Forest, Inyo County, California. The Inyo...

  8. Efficient algorithms for analyzing the singularly perturbed boundary value problems of fractional order

    Science.gov (United States)

    Sayevand, K.; Pichaghchi, K.

    2018-04-01

    In this paper, we were concerned with the description of the singularly perturbed boundary value problems in the scope of fractional calculus. We should mention that, one of the main methods used to solve these problems in classical calculus is the so-called matched asymptotic expansion method. However we shall note that, this was not achievable via the existing classical definitions of fractional derivative, because they do not obey the chain rule which one of the key elements of the matched asymptotic expansion method. In order to accommodate this method to fractional derivative, we employ a relatively new derivative so-called the local fractional derivative. Using the properties of local fractional derivative, we extend the matched asymptotic expansion method to the scope of fractional calculus and introduce a reliable new algorithm to develop approximate solutions of the singularly perturbed boundary value problems of fractional order. In the new method, the original problem is partitioned into inner and outer solution equations. The reduced equation is solved with suitable boundary conditions which provide the terminal boundary conditions for the boundary layer correction. The inner solution problem is next solved as a solvable boundary value problem. The width of the boundary layer is approximated using appropriate resemblance function. Some theoretical results are established and proved. Some illustrating examples are solved and the results are compared with those of matched asymptotic expansion method and homotopy analysis method to demonstrate the accuracy and efficiency of the method. It can be observed that, the proposed method approximates the exact solution very well not only in the boundary layer, but also away from the layer.

  9. Three symmetric positive solutions of fourth-order singular nonlocal boundary value problems

    Directory of Open Access Journals (Sweden)

    Fuyi Xu

    2011-12-01

    Full Text Available In this paper, we study the existence of three positive solutions of fourth-order singular nonlocal boundary value problems. We show that there exist triple symmetric positive solutions by using Leggett-Williams fixed-point theorem. The conclusions in this paper essentially extend and improve some known results.

  10. Aspen Delineation - Sierra State Parks [ds380

    Data.gov (United States)

    California Natural Resource Agency — The database represents delineations of aspen stands associated with stand assessment data (SIERRA_SP_PTS) collected in aspen stands on lands administered by the...

  11. Aspen Delineation - Sequoia National Forest [ds378

    Data.gov (United States)

    California Natural Resource Agency — The database represents delineations of aspen stands associated with stand assessment data (SEQUOIA_NF_PTS) collected in aspen stands in the Cannell Meadows Ranger...

  12. Initial-value problems for first-order differential recurrence equations with auto-convolution

    Directory of Open Access Journals (Sweden)

    Mircea Cirnu

    2011-01-01

    Full Text Available A differential recurrence equation consists of a sequence of differential equations, from which must be determined by recurrence a sequence of unknown functions. In this article, we solve two initial-value problems for some new types of nonlinear (quadratic first order homogeneous differential recurrence equations, namely with discrete auto-convolution and with combinatorial auto-convolution of the unknown functions. In both problems, all initial values form a geometric progression, but in the second problem the first initial value is exempted and has a prescribed form. Some preliminary results showing the importance of the initial conditions are obtained by reducing the differential recurrence equations to algebraic type. Final results about solving the considered initial value problems, are shown by mathematical induction. However, they can also be shown by changing the unknown functions, or by the generating function method. So in a remark, we give a proof of the first theorem by the generating function method.

  13. The MLH1 c.1852_1853delinsGC (p.K618A variant in colorectal cancer: genetic association study in 18,723 individuals.

    Directory of Open Access Journals (Sweden)

    Anna Abulí

    Full Text Available Colorectal cancer is one of the most frequent neoplasms and an important cause of mortality in the developed world. Mendelian syndromes account for about 5% of the total burden of CRC, being Lynch syndrome and familial adenomatous polyposis the most common forms. Lynch syndrome tumors develop mainly as a consequence of defective DNA mismatch repair associated with germline mutations in MLH1, MSH2, MSH6 and PMS2. A significant proportion of variants identified by screening these genes correspond to missense or noncoding changes without a clear pathogenic consequence, and they are designated as "variants of uncertain significance", being the c.1852_1853delinsGC (p.K618A variant in the MLH1 gene a clear example. The implication of this variant as a low-penetrance risk variant for CRC was assessed in the present study by performing a case-control study within a large cohort from the COGENT consortium-COST Action BM1206 including 18,723 individuals (8,055 colorectal cancer cases and 10,668 controls and a case-only genotype-phenotype correlation with several clinical and pathological characteristics restricted to the Epicolon cohort. Our results showed no involvement of this variant as a low-penetrance variant for colorectal cancer genetic susceptibility and no association with any clinical and pathological characteristics including family history for this neoplasm or Lynch syndrome.

  14. An Augmented Lagrangian Method for the Optimal H∞ Model Order Reduction Problem

    Directory of Open Access Journals (Sweden)

    Hongli Yang

    2017-01-01

    Full Text Available This paper treats the computational method of the optimal H∞ model order reduction (MOR problem of linear time-invariant (LTI systems. Optimal solution of MOR problem of LTI systems can be obtained by solving the LMIs feasibility coupling with a rank inequality constraint, which makes the solutions much harder to be obtained. In this paper, we show that the rank inequality constraint can be formulated as a linear rank function equality constraint. Properties of the linear rank function are discussed. We present an iterative algorithm based on augmented Lagrangian method by replacing the rank inequality with the linear rank function. Convergence analysis of the algorithm is given, which is distinct to the now available heuristic methods. Numerical experiments for the MOR problems of continuous LTI system illustrate the practicality of our method.

  15. Problems And Prospects Of The European Regional Order

    Directory of Open Access Journals (Sweden)

    L. A. Dymova

    2017-01-01

    Full Text Available For the last few decades, the system of international relations continues to change. One of the key components of the emerging international order is the European regional order, which currently goes through deep transformations associated with changes of the international system and structural reconstruction of the European communities. The formation of the European regional system is a complex international political process, which is based on various political, social, economic, cultural, historical and other factors. Since the end of the World war II the European Union constitutes a political and institutional basis of relations both between member states and with the rest of the world. However, today the European Union runs through a systemic crisis embodied by ongoing economic and financial downturn as well as a crisis of socio-political structures and models of governance that now threaten the existence of the Union itself. Institutional problems are aggravated against the background of crises in highly sensitive areas such as economy and security, as well as uncertainties in the external international environment. All these factors undermine the ability of the EU to play a decisive role in building a European regional order. The emphasis is shifting towards particular countries, with the greater potential in shaping the international agenda and giving an effective response to modern challenges and threats. Building a stable architecture of the European security system is one of the essential conditions of the European regional order, however contradicting approaches of the parties acknowledge that political and ideological barriers between the East and the West continue to exist. In the context of increasing security threats transatlantic partnership does not lose the relevance though the tough course of the US and its desire to reinforce its leadership in Europe often meets the extreme disapproval on the part of the Europeans. Russian

  16. An algorithm for determining the K-best solutions of the one-dimensional Knapsack problem

    Directory of Open Access Journals (Sweden)

    Horacio Hideki Yanasse

    2000-06-01

    Full Text Available In this work we present an enumerative scheme for determining the K-best solutions (K > 1 of the one dimensional knapsack problem. If n is the total number of different items and b is the knapsack's capacity, the computational complexity of the proposed scheme is bounded by O(Knb with memory requirements bounded by O(nb. The algorithm was implemented in a workstation and computational tests for varying values of the parameters were performed.Neste trabalho apresenta-se um esquema enumerativo para se determinar as K-melhores (K > 1 soluções para o problema da mochila unidimensional. Se n é o número total de itens diferentes e b é a capacidade da mochila, a complexidade computacional do esquema proposto é limitado por O(Knb. O algoritmo foi implementado em uma estação de trabalho e testes computacionais foram realizados variando-se diferentes parâmetros do problema.

  17. Aspen Delineation - Lassen National Forest [ds372

    Data.gov (United States)

    California Natural Resource Agency — The database represents delineations of aspen stands associated with stand assessment data (LASSEN_NF_EAGLELAKE_PTS) collected in aspen stands in the in the Eagle...

  18. Automated delineation of stroke lesions using brain CT images

    Directory of Open Access Journals (Sweden)

    Céline R. Gillebert

    2014-01-01

    Full Text Available Computed tomographic (CT images are widely used for the identification of abnormal brain tissue following infarct and hemorrhage in stroke. Manual lesion delineation is currently the standard approach, but is both time-consuming and operator-dependent. To address these issues, we present a method that can automatically delineate infarct and hemorrhage in stroke CT images. The key elements of this method are the accurate normalization of CT images from stroke patients into template space and the subsequent voxelwise comparison with a group of control CT images for defining areas with hypo- or hyper-intense signals. Our validation, using simulated and actual lesions, shows that our approach is effective in reconstructing lesions resulting from both infarct and hemorrhage and yields lesion maps spatially consistent with those produced manually by expert operators. A limitation is that, relative to manual delineation, there is reduced sensitivity of the automated method in regions close to the ventricles and the brain contours. However, the automated method presents a number of benefits in terms of offering significant time savings and the elimination of the inter-operator differences inherent to manual tracing approaches. These factors are relevant for the creation of large-scale lesion databases for neuropsychological research. The automated delineation of stroke lesions from CT scans may also enable longitudinal studies to quantify changes in damaged tissue in an objective and reproducible manner.

  19. A Modular Low-Complexity ECG Delineation Algorithm for Real-Time Embedded Systems.

    Science.gov (United States)

    Bote, Jose Manuel; Recas, Joaquin; Rincon, Francisco; Atienza, David; Hermida, Roman

    2018-03-01

    This work presents a new modular and low-complexity algorithm for the delineation of the different ECG waves (QRS, P and T peaks, onsets, and end). Involving a reduced number of operations per second and having a small memory footprint, this algorithm is intended to perform real-time delineation on resource-constrained embedded systems. The modular design allows the algorithm to automatically adjust the delineation quality in runtime to a wide range of modes and sampling rates, from a ultralow-power mode when no arrhythmia is detected, in which the ECG is sampled at low frequency, to a complete high-accuracy delineation mode, in which the ECG is sampled at high frequency and all the ECG fiducial points are detected, in the case of arrhythmia. The delineation algorithm has been adjusted using the QT database, providing very high sensitivity and positive predictivity, and validated with the MIT database. The errors in the delineation of all the fiducial points are below the tolerances given by the Common Standards for Electrocardiography Committee in the high-accuracy mode, except for the P wave onset, for which the algorithm is above the agreed tolerances by only a fraction of the sample duration. The computational load for the ultralow-power 8-MHz TI MSP430 series microcontroller ranges from 0.2% to 8.5% according to the mode used.

  20. PLASTIC AND GLASS GREENHOUSES DETECTION AND DELINEATION FROM WORLDVIEW-2 SATELLITE IMAGERY

    Directory of Open Access Journals (Sweden)

    D. Koc-San

    2016-06-01

    Full Text Available Greenhouse detection using remote sensing technologies is an important research area for yield estimation, sustainable development, urban and rural planning and management. An approach was developed in this study for the detection and delineation of greenhouse areas from high resolution satellite imagery. Initially, the candidate greenhouse patches were detected using supervised classification techniques. For this purpose, Maximum Likelihood (ML, Random Forest (RF, and Support Vector Machines (SVM classification techniques were applied and compared. Then, sieve filter and morphological operations were performed for improving the classification results. Finally, the obtained candidate plastic and glass greenhouse areas were delineated using boundary tracing and Douglas Peucker line simplification algorithms. The proposed approach was implemented in the Kumluca district of Antalya, Turkey utilizing pan-sharpened WorldView-2 satellite imageries. Kumluca is the prominent district of Antalya with greenhouse cultivation and includes both plastic and glass greenhouses intensively. When the greenhouse classification results were analysed, it can be stated that the SVM classification provides most accurate results and RF classification follows this. The SVM classification overall accuracy was obtained as 90.28%. When the greenhouse boundary delineation results were considered, the plastic greenhouses were delineated with 92.11% accuracy, while glass greenhouses were delineated with 80.67% accuracy. The obtained results indicate that, generally plastic and glass greenhouses can be detected and delineated successfully from WorldView-2 satellite imagery.

  1. High-order multi-implicit spectral deferred correction methods for problems of reactive flow

    International Nuclear Information System (INIS)

    Bourlioux, Anne; Layton, Anita T.; Minion, Michael L.

    2003-01-01

    Models for reacting flow are typically based on advection-diffusion-reaction (A-D-R) partial differential equations. Many practical cases correspond to situations where the relevant time scales associated with each of the three sub-processes can be widely different, leading to disparate time-step requirements for robust and accurate time-integration. In particular, interesting regimes in combustion correspond to systems in which diffusion and reaction are much faster processes than advection. The numerical strategy introduced in this paper is a general procedure to account for this time-scale disparity. The proposed methods are high-order multi-implicit generalizations of spectral deferred correction methods (MISDC methods), constructed for the temporal integration of A-D-R equations. Spectral deferred correction methods compute a high-order approximation to the solution of a differential equation by using a simple, low-order numerical method to solve a series of correction equations, each of which increases the order of accuracy of the approximation. The key feature of MISDC methods is their flexibility in handling several sub-processes implicitly but independently, while avoiding the splitting errors present in traditional operator-splitting methods and also allowing for different time steps for each process. The stability, accuracy, and efficiency of MISDC methods are first analyzed using a linear model problem and the results are compared to semi-implicit spectral deferred correction methods. Furthermore, numerical tests on simplified reacting flows demonstrate the expected convergence rates for MISDC methods of orders three, four, and five. The gain in efficiency by independently controlling the sub-process time steps is illustrated for nonlinear problems, where reaction and diffusion are much stiffer than advection. Although the paper focuses on this specific time-scales ordering, the generalization to any ordering combination is straightforward

  2. DISPL-1, 2. Order Nonlinear Partial Differential Equation System Solution for Kinetics Diffusion Problems

    International Nuclear Information System (INIS)

    Leaf, G.K.; Minkoff, M.

    1982-01-01

    1 - Description of problem or function: DISPL1 is a software package for solving second-order nonlinear systems of partial differential equations including parabolic, elliptic, hyperbolic, and some mixed types. The package is designed primarily for chemical kinetics- diffusion problems, although not limited to these problems. Fairly general nonlinear boundary conditions are allowed as well as inter- face conditions for problems in an inhomogeneous medium. The spatial domain is one- or two-dimensional with rectangular Cartesian, cylindrical, or spherical (in one dimension only) geometry. 2 - Method of solution: The numerical method is based on the use of Galerkin's procedure combined with the use of B-Splines (C.W.R. de-Boor's B-spline package) to generate a system of ordinary differential equations. These equations are solved by a sophisticated ODE software package which is a modified version of Hindmarsh's GEAR package, NESC Abstract 592. 3 - Restrictions on the complexity of the problem: The spatial domain must be rectangular with sides parallel to the coordinate geometry. Cross derivative terms are not permitted in the PDE. The order of the B-Splines is at most 12. Other parameters such as the number of mesh points in each coordinate direction, the number of PDE's etc. are set in a macro table used by the MORTRAn2 preprocessor in generating the object code

  3. Higher-order probabilistic perceptrons as Bayesian inference engines

    International Nuclear Information System (INIS)

    Clark, J.W.; Ristig, M.L.

    1994-08-01

    This letter makes explicit a structural connection between the Bayes optimal classifier operating on K binary input variables and corresponding two-layer perceptron having normalized output activities and couplings from input to output units of all orders up to K. Given a large and unbiased training set and an effective learning algorithm, such a neural network should be able to learn the statistics of the classification problem and match the a posteriori probabilities given by the Bayes optimal classifier. (author). 18 refs

  4. Tools to analyse and display variations in anatomical delineation

    International Nuclear Information System (INIS)

    Ebert, Martin A.; McDermott, L.N.; Haworth, A; Van der Wath, E.; Hooton, B.

    2012-01-01

    Variations in anatomical delineation, principally due to a combination of inter-observer contributions and image-specificity, remain one of the most significant impediments to geometrically-accurate radiotherapy. Quantification of spatial variability of the delineated contours comprising a structure can be made with a variety of metrics, and the availability of software tools to apply such metrics to data collected during inter-observer or repeat-imaging studies would allow their validation. A suite of such tools have been developed which use an Extensible Markup Language format for the exchange of delineated 3D structures with radiotherapy planning or review systems. These tools provide basic operations for manipulating and operating on individual structures and related structure sets, and for deriving statistics on spatial variations of contours that can be mapped onto the surface of a reference structure. Use of these tools on a sample dataset is demonstrated together with import and display of results in the SWAN treatment plan review system.

  5. Magnetic ordering of quasi-1 D S=1/2 Heisenberg antiferromagnet Cu benzoate at sub-mK temperatures

    International Nuclear Information System (INIS)

    Karaki, Y.; Masutomi, R.; Kubota, M.; Ishimoto, H.; Asano, T.; Ajiro, Y.

    2003-01-01

    We have measured the AC susceptibility of quasi-1D S=1/2 Heisenberg antiferromagnet Cu benzoate at temperatures down to 0.2 mK. A sharp susceptibility peak is observed at 0.8 mK under an earth field. This fact indicates a 3D ordering of linear chains coupled by a weak magnetic interaction between chains

  6. The radio galaxy K-z relation to z ~ 4.5

    OpenAIRE

    Jarvis, Matt J.; Rawlings, Steve; Eales, Steve; Blundell, Katherine M.; Willott, Chris J.

    2001-01-01

    Using a new radio sample, 6C* designed to find radio galaxies at z > 4 along with the complete 3CRR and 6CE sample we extend the radio galaxy K-z relation to z~4.5. The 6C* K-z data significantly improve delineation of the K-z relation for radio galaxies at high redshift (z > 2). Accounting for non-stellar contamination, and for correlations between radio luminosity and estimates of stellar mass, we find little support for previous claims that the underlying scatter in the stellar luminosity ...

  7. Using analytic element models to delineate drinking water source protection areas.

    Science.gov (United States)

    Raymond, Heather A; Bondoc, Michael; McGinnis, John; Metropulos, Kathy; Heider, Pat; Reed, Allison; Saines, Steve

    2006-01-01

    Since 1999, Ohio EPA hydrogeologists have used two analytic element models (AEMs), the proprietary software GFLOW and U.S. EPA's WhAEM, to delineate protection areas for 535 public water systems. Both models now use the GFLOW2001 solution engine, integrate well with Geographic Information System (GIS) technology, have a user-friendly graphical interface, are capable of simulating a variety of complex hydrogeologic settings, and do not rely upon a model grid. These features simplify the modeling process and enable AEMs to bridge the gap between existing simplistic delineation methods and more complex numerical models. Ohio EPA hydrogeologists demonstrated that WhAEM2000 and GFLOW2000 were capable of producing capture zones similar to more widely accepted models by applying the AEMs to eight sites that had been previously delineated using other methods. After the Ohio EPA delineated protection areas using AEMs, more simplistic delineation methods used by other states (volumetric equation and arbitrary fixed radii) were applied to the same water systems to compare the differences between various methods. GIS software and two-tailed paired t-tests were used to quantify the differences in protection areas and analyze the data. The results of this analysis demonstrate that AEMs typically produce significantly different protection areas than the most simplistic delineation methods, in terms of total area and shape. If the volumetric equation had been used instead of AEMs, Ohio would not have protected 265 km2 of critical upgradient area and would have overprotected 269 km2 of primarily downgradient land. Since an increasing number of land-use restrictions are being tied to drinking water protection areas, this analysis has broad policy implications.

  8. High Order Finite Element Method for the Lambda modes problem on hexagonal geometry

    International Nuclear Information System (INIS)

    Gonzalez-Pintor, S.; Ginestar, D.; Verdu, G.

    2009-01-01

    A High Order Finite Element Method to approximate the Lambda modes problem for reactors with hexagonal geometry has been developed. This method is based on the expansion of the neutron flux in terms of the modified Dubiner's polynomials on a triangular mesh. This mesh is fixed and the accuracy of the method is improved increasing the degree of the polynomial expansions without the necessity of remeshing. The performance of method has been tested obtaining the dominant Lambda modes of different 2D reactor benchmark problems.

  9. Rethinking Pedagogy for Second-Order Differential Equations: A Simplified Approach to Understanding Well-Posed Problems

    Science.gov (United States)

    Tisdell, Christopher C.

    2017-01-01

    Knowing an equation has a unique solution is important from both a modelling and theoretical point of view. For over 70 years, the approach to learning and teaching "well posedness" of initial value problems (IVPs) for second- and higher-order ordinary differential equations has involved transforming the problem and its analysis to a…

  10. Mixed problem with integral boundary condition for a high order mixed type partial differential equation

    OpenAIRE

    M. Denche; A. L. Marhoune

    2003-01-01

    In this paper, we study a mixed problem with integral boundary conditions for a high order partial differential equation of mixed type. We prove the existence and uniqueness of the solution. The proof is based on energy inequality, and on the density of the range of the operator generated by the considered problem.

  11. Analisa Sistem Ordering Material Plastik pada PT XYZ dengan menggunakan Metode Kepner-Tregoe Problem Solving

    OpenAIRE

    Jonny Lin

    2015-01-01

    PT XYZ has faced a problem related to its plastik material ordering system in which its quantity purchase order calculation result was so different with its manual calculation that its material logictic staff was needed to make a proper correction. Therefore, this research was taken in order to help the staff to analyze its root cause so that the proper improvement could be taken and the quantity purchase order calculation will be equal to its manual calculation. By deploying Kepner-Tregoe pr...

  12. Transient flow conditions in probabilistic wellhead protection: importance and ways to manage spatial and temporal uncertainty in capture zone delineation

    Science.gov (United States)

    Enzenhoefer, R.; Rodriguez-Pretelin, A.; Nowak, W.

    2012-12-01

    "From an engineering standpoint, the quantification of uncertainty is extremely important not only because it allows estimating risk but mostly because it allows taking optimal decisions in an uncertain framework" (Renard, 2007). The most common way to account for uncertainty in the field of subsurface hydrology and wellhead protection is to randomize spatial parameters, e.g. the log-hydraulic conductivity or porosity. This enables water managers to take robust decisions in delineating wellhead protection zones with rationally chosen safety margins in the spirit of probabilistic risk management. Probabilistic wellhead protection zones are commonly based on steady-state flow fields. However, several past studies showed that transient flow conditions may substantially influence the shape and extent of catchments. Therefore, we believe they should be accounted for in the probabilistic assessment and in the delineation process. The aim of our work is to show the significance of flow transients and to investigate the interplay between spatial uncertainty and flow transients in wellhead protection zone delineation. To this end, we advance our concept of probabilistic capture zone delineation (Enzenhoefer et al., 2012) that works with capture probabilities and other probabilistic criteria for delineation. The extended framework is able to evaluate the time fraction that any point on a map falls within a capture zone. In short, we separate capture probabilities into spatial/statistical and time-related frequencies. This will provide water managers additional information on how to manage a well catchment in the light of possible hazard conditions close to the capture boundary under uncertain and time-variable flow conditions. In order to save computational costs, we take advantage of super-positioned flow components with time-variable coefficients. We assume an instantaneous development of steady-state flow conditions after each temporal change in driving forces, following

  13. Description of the ππ → ππ, ππ → K anti K and K anti KK anti K process in the framework of the N/D method

    International Nuclear Information System (INIS)

    Khenner, V.K.

    1978-01-01

    On the basis of the dispersion model the ππ → ππ, ππ → K anti K and K anti KK anti K processes in the state with I=J=.0 are studied. The processes are considered using the N/D matrix method, permitting to solve precisely the related system of dispersion ratios for the partial amplitudes. It is shown that the discovery of the inelastic channel can be effectively taken into account by the introduction of the CDD (Castillejo-Dality-Dyson) term into the elastic scattering amplitude. It is established, that at a given ππ → ππ amplitude the transition from the complete multichannel problem, considered by the matrix method, to the linear problem leads to the solution, where all arbitrary constants are fixed in the case when zeros of the ππ → K anti K and ππ → ππ amplitudes coincide. In this case the ππ → K anti K amplitude coincides with that obtained by the Omnes-Muskhelishvili method. Other processes, where the interaction in the initial or final state is insignificant, can be also studied by such a method not resulting in the appearance of additional arbitrary parameters. The consideration of the problem of a resonance position in various channels has shown, that the matrix method does not obligatorily result in the appearance of the resonance with the permitted quantum numbers in all the interconnected channels

  14. Delineating organs at risk in radiation therapy

    CERN Document Server

    Ausili Cèfaro, Giampiero; Perez, Carlos A

    2014-01-01

    This book offers an invaluable guide to the delineation of organs at risk of toxicity in patients undergoing radiotherapy. It details the radiological anatomy of organs at risk as seen on typical radiotherapy planning CT scans.

  15. Numerical solution of sixth-order boundary-value problems using Legendre wavelet collocation method

    Science.gov (United States)

    Sohaib, Muhammad; Haq, Sirajul; Mukhtar, Safyan; Khan, Imad

    2018-03-01

    An efficient method is proposed to approximate sixth order boundary value problems. The proposed method is based on Legendre wavelet in which Legendre polynomial is used. The mechanism of the method is to use collocation points that converts the differential equation into a system of algebraic equations. For validation two test problems are discussed. The results obtained from proposed method are quite accurate, also close to exact solution, and other different methods. The proposed method is computationally more effective and leads to more accurate results as compared to other methods from literature.

  16. Mixed FEM for Second Order Elliptic Problems on Polygonal Meshes with BEM-Based Spaces

    KAUST Repository

    Efendiev, Yalchin

    2014-01-01

    We present a Boundary Element Method (BEM)-based FEM for mixed formulations of second order elliptic problems in two dimensions. The challenge, we would like to address, is a proper construction of H(div)-conforming vector valued trial functions on arbitrary polygonal partitions of the domain. The proposed construction generates trial functions on polygonal elements which inherit some of the properties of the unknown solution. In the numerical realization, the relevant local problems are treated by means of boundary integral formulations. We test the accuracy of the method on two model problems. © 2014 Springer-Verlag.

  17. Measurement Invariance of Second-Order Factor Model of the Multifactor Leadership Questionnaire (MLQ) across K-12 Principal Gender

    Science.gov (United States)

    Xu, Lihua; Wubbena, Zane; Stewart, Trae

    2016-01-01

    Purpose: The purpose of this paper is to investigate the factor structure and the measurement invariance of the Multifactor Leadership Questionnaire (MLQ) across gender of K-12 school principals (n=6,317) in the USA. Design/methodology/approach: Nine first-order factor models and four second-order factor models were tested using confirmatory…

  18. Dose due to {sup 40}K

    Energy Technology Data Exchange (ETDEWEB)

    Escareno J, E.; Vega C, H. R., E-mail: edmundoej@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2011-10-15

    The dose due to {sup 40}K has been estimated. Potassium is one of the most abundant elements in nature, being approximately 2% of the Earth's crust. Potassium has three isotopes {sup 39}K, {sup 40}K and {sup 41}K, two are stable while {sup 40}K is radioactive with a half life of 1.2x10{sup 9} years; there is 0.0117% {sup 40}K-to-K ratio. Potassium plays an important role in plants, animals and humans growth and reproduction. Due to the fact that K is an essential element for humans, {sup 40}K is the most abundant radioisotope in human body. In order to keep good health conditions K must be intake at daily basis trough food and beverages, however when K in ingested above the requirements produce adverse health effects in persons with renal, cardiac and hypertension problems or suffering diabetes. In 89.3% {sup 40}K decays to {sup 40}C through {beta}-decay, in 10.3% decays through electronic capture and emitting 1.46 MeV {gamma}-ray. K is abundant in soil, construction materials, sand thus {gamma}-rays produced during {sup 40}K decay contribute to external dose. For K in the body practically all {sup 40}K decaying energy is absorbed by the body; thus {sup 40}K contributes to total dose in humans and it is important to evaluate its contribution. In this work a set of {sup 40}K sources were prepared using different amounts of KCl salt, a {gamma}-ray spectrometer with a NaI(Tl) was characterized to standardized the sources in order to evaluate the dose due to {sup 40}K. Using thermoluminescent dosemeters the dose due to {sup 40}K was measured and related to the amount of {sup 40}K {gamma}-ray activity. (Author)

  19. Y2K

    OpenAIRE

    Schmitt-Grohe, Stephanie; Uribe, Martin

    1998-01-01

    As the millennium draws to an end, the threat posed by the Year 2000 (Y2K) problem is inducing vast private and public spending on its remediation. In this paper, we model the Y2K problem as an anticipated, permanent loss in output whose magnitude can be lessened by investing resources in advance. We embed the Y2K problem into a dynamic general equilibrium framework and show that our model replicates three observed characteristics of the dynamics triggered by the Y2K bug: (1) Precautionary in...

  20. Determination of Equilibrium Constant and Relative Brightness in FRET-FCS by Including the Third-Order Correlations.

    Science.gov (United States)

    Meng, Lingyi; He, Shanshan; Zhao, Xin Sheng

    2017-12-21

    Fluorescence correlation spectroscopy (FCS) encodes the information on the equilibrium constant (K), the relative fluorescence brightness of fluorophore (Q), and the forward and backward reaction rate constants (k + and k - ) on a physical or chemical relaxation. However, it has been a long-standing problem to completely resolve the FCS data to get the thermodynamic and kinetic information. Recently, we have solved the problem for fluorescence autocorrelation spectroscopy (FACS). Here, we extend the method to fluorescence cross-correlation spectroscopy (FCCS), which appears when FCS is coupled with fluorescence resonance energy transfer (FRET). Among 12 total second-order and third-order pre-exponential factors in a relaxation process probed by the FRET-FCS technique, 3 are independent. We presented and discussed 3 sets of explicit solutions to use these pre-exponential factors to calculate K and Q. Together with the relaxation time, the acquired K will allow people to obtain k + and k - , so that the goal of deciphering the FRET-FCS data will be fully reached. The theory is verified by extensive computer simulations and tested experimentally on a system of oligonucleotide hybridization.

  1. The 'final order' problem

    NARCIS (Netherlands)

    Teunter, RH; Haneveld, WKK

    1998-01-01

    When the service department of a company selling machines stops producing and supplying spare parts for certain machines, customers are offered an opportunity to place a so-called final order for these spare parts. We focus on one customer with one machine. The customer plans to use this machine up

  2. Elliptic boundary value problems with fractional regularity data the first order approach

    CERN Document Server

    Amenta, Alex

    2018-01-01

    In this monograph the authors study the well-posedness of boundary value problems of Dirichlet and Neumann type for elliptic systems on the upper half-space with coefficients independent of the transversal variable and with boundary data in fractional Hardy-Sobolev and Besov spaces. The authors use the so-called "first order approach" which uses minimal assumptions on the coefficients and thus allows for complex coefficients and for systems of equations. This self-contained exposition of the first order approach offers new results with detailed proofs in a clear and accessible way and will become a valuable reference for graduate students and researchers working in partial differential equations and harmonic analysis.

  3. Novel Numerical Methods for Optimal Control Problems Involving Fractional-Order Differential Equations

    Science.gov (United States)

    2018-03-14

    UNIVERSITY OF TECHNOLOGY Final Report 03/14/2018 DISTRIBUTION A: Distribution approved for public release. AF Office Of Scientific Research (AFOSR...optimal control problems involving fractional-order differential equations Wang, Song Curtin University of Technology Kent Street, Bentley WA6102...Article history : Received 3 October 2016 Accepted 26 March 2017 Available online 29 April 2017 Keywords: Hamilton–Jacobi–Bellman equation Financial

  4. The Curve Number Concept as a Driver for Delineating Hydrological Response Units

    Directory of Open Access Journals (Sweden)

    Eleni Savvidou

    2018-02-01

    Full Text Available In this paper, a new methodology for delineating Hydrological Response Units (HRUs, based on the Curve Number (CN concept, is presented. Initially, a semi-automatic procedure in a GIS environment is used to produce basin maps of distributed CN values as the product of the three classified layers, soil permeability, land use/land cover characteristics and drainage capacity. The map of CN values is used in the context of model parameterization, in order to identify the essential number and spatial extent of HRUs and, consequently, the number of control variables of the calibration problem. The new approach aims at reducing the subjectivity introduced by the definition of HRUs and providing parsimonious modelling schemes. In particular, the CN-based parameterization (1 allows the user to assign as many parameters as can be supported by the available hydrological information, (2 associates the model parameters with anticipated basin responses, as quantified in terms of CN classes across HRUs, and (3 reduces the effort for model calibration, simultaneously ensuring good predictive capacity. The advantages of the proposed approach are demonstrated in the hydrological simulation of the Nedontas River Basin, Greece, where parameterizations of different complexities are employed in a recently improved version of the HYDROGEIOS model. A modelling experiment with a varying number of HRUs, where the parameter estimation problem was handled through automatic optimization, showed that the parameterization with three HRUs, i.e., equal to the number of flow records, ensured the optimal performance. Similarly, tests with alternative HRU configurations confirmed that the optimal scores, both in calibration and validation, were achieved by the CN-based approach, also resulting in parameters values across the HRUs that were in agreement with their physical interpretation.

  5. K-dron, its mathematical modeling and applications

    OpenAIRE

    Janusz Kapusta; Jerzy Gawinecki; Jarosław Łazuka; Józef Rafa

    2016-01-01

    In this paper we present the definition of K-dron, new geometrical form discovered by Janusz Kapusta in 1985 in New York, its history and connection between geometry and symmetry of a cube. It is worth to emphasize that the authors have derived new formulae for the surface of K-dron using the Laplaceatransform in order to obtain the solution of the boundary-value problem for the partial differential equation describing the vibration of the string. The formula proved by us in this paper is cle...

  6. 139La and 63Cu NMR investigation of charge order in La2CuO4 +y (Tc=42 K)

    Science.gov (United States)

    Imai, T.; Lee, Y. S.

    2018-03-01

    We report 139La and 63Cu NMR investigation of the successive charge order, spin order, and superconducting transitions in superoxygenated La2CuO4 +y single crystal with stage-4 excess oxygen order at Tstage≃290 K. We show that the stage-4 order induces tilting of CuO6 octahedra below Tstage, which in turn causes 139La NMR line broadening. The structural distortion continues to develop far below Tstage, and completes at Tcharge≃60 K, where charge order sets in. This sequence is reminiscent of the the charge-order transition in Nd codoped La1.88Sr0.12CuO4 that sets in once the low-temperature tetragonal phase is established. We also show that the paramagnetic 63Cu NMR signals are progressively wiped out below Tcharge due to enhanced low-frequency spin fluctuations in charge-ordered domains, but the residual 63Cu NMR signals continue to exhibit the characteristics expected for optimally doped superconducting CuO2 planes. This indicates that charge order in La2CuO4 +y does not take place uniformly in space. In addition, unlike the typical second-order magnetic phase transitions, low-frequency Cu spin fluctuations as probed by 139La nuclear spin-lattice relaxation rate do not exhibit critical divergence at Tspin(≃Tc ) =42 K. These findings, including the spatially inhomogeneous nature of the charge-ordered state, are qualitatively similar to the case of La1.885Sr0.115CuO4 [Imai et al., Phys. Rev. B 96, 224508 (2017), 10.1103/PhysRevB.96.224508 and Arsenault et al., Phys. Rev. B 97, 064511 (2018), 10.1103/PhysRevB.97.064511], but both charge and spin order take place more sharply in the present case.

  7. Non-integrability of the generalized spring-pendulum problem

    International Nuclear Information System (INIS)

    Maciejewski, Andrzej J; Przybylska, Maria; Weil, Jacques-Arthur

    2004-01-01

    We investigate a generalization of the three-dimensional spring-pendulum system. The problem depends on two real parameters (k, a), where k is the Young modulus of the spring and a describes the nonlinearity of elastic forces. We show that this system is not integrable when k ≠ -a. We carefully investigated the case k = -a when the necessary condition for integrability given by the Morales-Ruiz-Ramis theory is satisfied. We discuss an application of the higher order variational equations for proving the non-integrability in this case

  8. Upgrade of RMS computers for Y2K problems in RX and related building of HANARO

    International Nuclear Information System (INIS)

    Kim, Jung Taek; Kim, J. T.; Ham, C. S.; Kim, C. H.; Lee, Bong Jae; Jae, Yoo Kyung

    2000-08-01

    The Objectives of this Project are as follows : - To resolve the problems of Y2k and operation and maintenance of RMS Computers in RX and related Building of HANARO - To upgrade 486 PC to Pentium II PC - To make Windows NT-Based platform for aspects of user - To make an information structure for radiation using ireless and network devices The Contents of the Project are as follows : - To make Windows NT-Based platform for Radiation Monitoring System - To make Software Platform and Environment for the developing the application program - To design and implement Database Structure - To implement RS232c communication program between local indicators and scanning computers - To implement IEEE 802.3 ethernet communication program between scanning computers and RMTs - To implement user interface for radiation monitoring - To test and inspect Y2k problems

  9. Upgrade of RMS computers for Y2K problems in RX and related building of HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Taek; Kim, J. T.; Ham, C. S.; Kim, C. H.; Lee, Bong Jae; Jae, Yoo Kyung

    2000-08-01

    The Objectives of this Project are as follows : - To resolve the problems of Y2k and operation and maintenance of RMS Computers in RX and related Building of HANARO - To upgrade 486 PC to Pentium II PC - To make Windows NT-Based platform for aspects of user - To make an information structure for radiation using ireless and network devices The Contents of the Project are as follows : - To make Windows NT-Based platform for Radiation Monitoring System - To make Software Platform and Environment for the developing the application program - To design and implement Database Structure - To implement RS232c communication program between local indicators and scanning computers - To implement IEEE 802.3 ethernet communication program between scanning computers and RMTs - To implement user interface for radiation monitoring - To test and inspect Y2k problems.

  10. Singularity-free next-to-leading order ΔS=1 renormalization group evolution and ϵ{sub K}{sup ′}/ϵ{sub K} in the Standard Model and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Kitahara, Teppei [Institute for Theoretical Particle Physics (TTP), Karlsruhe Institute of Technology,Engesserstraße 7, Karlsruhe, D-76128 (Germany); Institute for Nuclear Physics (IKP), Karlsruhe Institute of Technology,Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen, D-76344 (Germany); Nierste, Ulrich; Tremper, Paul [Institute for Theoretical Particle Physics (TTP), Karlsruhe Institute of Technology,Engesserstraße 7, Karlsruhe, D-76128 (Germany)

    2016-12-16

    The standard analytic solution of the renormalization group (RG) evolution for the ΔS=1 Wilson coefficients involves several singularities, which complicate analytic solutions. In this paper we derive a singularity-free solution of the next-to-leading order (NLO) RG equations, which greatly facilitates the calculation of ϵ{sub K}{sup ′}, the measure of direct CP violation in K→ππ decays. Using our new RG evolution and the latest lattice results for the hadronic matrix elements, we calculate the ratio ϵ{sub K}{sup ′}/ϵ{sub K} (with ϵ{sub K} quantifying indirect CP violation) in the Standard Model (SM) at NLO to ϵ{sub K}{sup ′}/ϵ{sub K}=(1.06±5.07)×10{sup −4}, which is 2.8 σ below the experimental value. We also present the evolution matrix in the high-energy regime for calculations of new physics contributions and derive easy-to-use approximate formulae. We find that the RG amplification of new-physics contributions to Wilson coefficients of the electroweak penguin operators is further enhanced by the NLO corrections: if the new contribution is generated at the scale of 1–10 TeV, the RG evolution between the new-physics scale and the electroweak scale enhances these coefficients by 50–100%. Our solution contains a term of order α{sub EM}{sup 2}/α{sub s}{sup 2}, which is numerically unimportant for the SM case but should be included in studies of high-scale new-physics.

  11. Aspen Delineation - Klamath National Forest, EUI [ds368

    Data.gov (United States)

    California Natural Resource Agency — The database represents delineations of known aspen stands where aspen assessments were collected in the Klamath National Forest, Siskiyou County, California. The...

  12. Second-Order Necessary Optimality Conditions for Some State-Constrained Control Problems of Semilinear Elliptic Equations

    International Nuclear Information System (INIS)

    Casas, E.; Troeltzsch, F.

    1999-01-01

    In this paper we are concerned with some optimal control problems governed by semilinear elliptic equations. The case of a boundary control is studied. We consider pointwise constraints on the control and a finite number of equality and inequality constraints on the state. The goal is to derive first- and second-order optimality conditions satisfied by locally optimal solutions of the problem

  13. Target volume delineation variation in radiotherapy for early stage rectal cancer in the Netherlands

    International Nuclear Information System (INIS)

    Nijkamp, Jasper; Haas-Kock, Danielle F.M. de; Beukema, Jannet C.; Neelis, Karen J.; Woutersen, Dankert; Ceha, Heleen; Rozema, Tom; Slot, Annerie; Vos-Westerman, Hanneke; Intven, Martijn; Spruit, Patty H.; Linden, Yvette van der; Geijsen, Debby; Verschueren, Karijn; Herk, Marcel B. van; Marijnen, Corrie A.M.

    2012-01-01

    Purpose: The aim of this study was to measure and improve the quality of target volume delineation by means of national consensus on target volume definition in early-stage rectal cancer. Methods and materials: The CTV’s for eight patients were delineated by 11 radiation oncologists in 10 institutes according to local guidelines (phase 1). After observer variation analysis a workshop was organized to establish delineation guidelines and a digital atlas, with which the same observers re-delineated the dataset (phase 2). Variation in volume, most caudal and cranial slice and local surface distance variation were analyzed. Results: The average delineated CTV volume decreased from 620 to 460 cc (p < 0.001) in phase 2. Variation in the caudal CTV border was reduced significantly from 1.8 to 1.2 cm SD (p = 0.01), while it remained 0.7 cm SD for the cranial border. The local surface distance variation (cm SD) reduced from 1.02 to 0.74 for anterior, 0.63 to 0.54 for lateral, 0.33 to 0.25 for posterior and 1.22 to 0.46 for the sphincter region, respectively. Conclusions: The large variation in target volume delineation could significantly be reduced by use of consensus guidelines and a digital delineation atlas. Despite the significant reduction there is still a need for further improvement.

  14. Aspen Delineation - Plumas National Forest, FRRD [ds376

    Data.gov (United States)

    California Natural Resource Agency — The database represents delineations of aspen stands associated with stand assessment data (PLUMAS_NF_FEATHERRIVER_PTS) collected in aspen stands in the Plumas...

  15. Delineating Urban Fringe Area by Land Cover Information Entropy—An Empirical Study of Guangzhou-Foshan Metropolitan Area, China

    Directory of Open Access Journals (Sweden)

    Junyi Huang

    2016-05-01

    Full Text Available Rapid urbanization has caused many environmental problems, such as the heat island effect, intensifying air pollution, pollution from runoff, loss of wildlife habitat, etc. Accurate evaluations of these problems demand an accurate delineation of the spatial extent of the urban fringe. Conceptual and analytical ambiguity of the urban fringe and a general lack of consensus among researchers have made its measurement very difficult. This study reports a compound and reliable method to delineate the urban fringe area using a case study. Based on the 'fringe effect' theory in landscape ecology, the existing land cover information entropy model for defining the urban fringe is renewed by incorporating scale theory, cartography and urban geography theory. Results show that the urban fringe area of Guangzhou and Foshan metropolitan area covers an area of 2031 km2, and it occupies over 31% of the total study area. Result evaluation by industry structure data shows satisfactory correspondence with different land cover types. This paper reports the method and outcome of an attempt to provide an objective, repeatable and generally applicable method for mapping its spatial extent from remote sensing imageries, and could be beneficial to relevant urban studies and urban fringe management projects.

  16. Recommendations for the delineation of organs at risk in ENT radiotherapy

    International Nuclear Information System (INIS)

    Ali, D.; Halimi, P.; Berges, O.; Deberne, M.; Botti, M.; Giraud, P.; Servagi-Vernat, S.

    2011-01-01

    Based on a literature survey, the authors propose recommendations for the delineation of the pharyngeal constrictor muscles, inner ear, larynx, buccal cavity, and temporomandibular joint. These recommendations of delineation of organs at risk are related to the functional anatomy of the considered structures, and correspond to volumes used in published surveys on dose-volume toxicity. They are simple and reproducible. Short communication

  17. Experimental pavement delineation treatments

    Science.gov (United States)

    Bryden, J. E.; Lorini, R. A.

    1981-06-01

    Visibility and durability of materials used to delineate shoulders and medians adjacent to asphalt pavements were evaluated. Materials evaluated were polysulfide and coal tar epoxies, one and two component polyesters, portland cement, acrylic paints, modified-alkyd traffic paint, preformed plastic tape, and thermoplastic markings. Neat applications, sand mortars, and surface treatments were installed in several geometric patterns including cross hatches, solid median treatments, and various widths of edge lines. Thermoplastic pavement markings generally performed very well, providing good visibility under adverse viewing conditions for at least 4 years. Thermoplastic 4 in. wide edge lines appear to provide adequate visibility for most conditions.

  18. Mixed FEM for Second Order Elliptic Problems on Polygonal Meshes with BEM-Based Spaces

    KAUST Repository

    Efendiev, Yalchin; Galvis, Juan; Lazarov, Raytcho; Weiß er, Steffen

    2014-01-01

    We present a Boundary Element Method (BEM)-based FEM for mixed formulations of second order elliptic problems in two dimensions. The challenge, we would like to address, is a proper construction of H(div)-conforming vector valued trial functions

  19. Existence of positive solutions for a multi-point four-order boundary-value problem

    Directory of Open Access Journals (Sweden)

    Le Xuan Truong

    2011-10-01

    Full Text Available The article shows sufficient conditions for the existence of positive solutions to a multi-point boundary-value problem for a fourth-order differential equation. Our main tools are the Guo-Krasnoselskii fixed point theorem and the monotone iterative technique. We also show that the set of positive solutions is compact.

  20. Remark on periodic boundary-value problem for second-order linear ordinary differential equations

    Czech Academy of Sciences Publication Activity Database

    Dosoudilová, M.; Lomtatidze, Alexander

    2018-01-01

    Roč. 2018, č. 13 (2018), s. 1-7 ISSN 1072-6691 Institutional support: RVO:67985840 Keywords : second-order linear equation * periodic boundary value problem * unique solvability Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 0.954, year: 2016 https://ejde.math.txstate.edu/Volumes/2018/13/abstr.html

  1. Recent Development of Multigrid Algorithms for Mixed and Noncomforming Methods for Second Order Elliptical Problems

    Science.gov (United States)

    Chen, Zhangxin; Ewing, Richard E.

    1996-01-01

    Multigrid algorithms for nonconforming and mixed finite element methods for second order elliptic problems on triangular and rectangular finite elements are considered. The construction of several coarse-to-fine intergrid transfer operators for nonconforming multigrid algorithms is discussed. The equivalence between the nonconforming and mixed finite element methods with and without projection of the coefficient of the differential problems into finite element spaces is described.

  2. The nonlocal boundary value problems for strongly singular higher-order nonlinear functional-differential equations

    Czech Academy of Sciences Publication Activity Database

    Mukhigulashvili, Sulkhan

    -, č. 35 (2015), s. 23-50 ISSN 1126-8042 Institutional support: RVO:67985840 Keywords : higher order functional differential equations * Dirichlet boundary value problem * strong singularity Subject RIV: BA - General Mathematics http://ijpam.uniud.it/online_issue/201535/03-Mukhigulashvili.pdf

  3. Target volume delineation in external beam partial breast irradiation: less inter-observer variation with preoperative- compared to postoperative delineation

    NARCIS (Netherlands)

    Leij, F. van der; Elkhuizen, P.H.M.; Janssen, T.M.; Poortmans, P.M.P.; Sangen, M. van der; Scholten, A.N.; Vliet-Vroegindeweij, C. van; Boersma, L.J.

    2014-01-01

    The challenge of adequate target volume definition in external beam partial breast irradiation (PBI) could be overcome with preoperative irradiation, due to less inter-observer variation. We compared the target volume delineation for external beam PBI on preoperative versus postoperative CT scans of

  4. Perturbative expansion and the initial value problem of the K.d.V. equations

    International Nuclear Information System (INIS)

    Turchetti, G.

    1980-01-01

    For the potential K.d.V. equation is considered a perturbation expansion in which the initial condition is imposed on the zeroth order term. The N soliton solutions turn out to be rational functions in the expansion parameter so that the perturbation series can be exactly summed by the [N-1/N] Pade approximants; moreover the [n-1/n] and [n/n] Pade approximants for n [pt

  5. Mixed problem with nonlocal boundary conditions for a third-order partial differential equation of mixed type

    OpenAIRE

    Denche, M.; Marhoune, A. L.

    2001-01-01

    We study a mixed problem with integral boundary conditions for a third-order partial differential equation of mixed type. We prove the existence and uniqueness of the solution. The proof is based on two-sided a priori estimates and on the density of the range of the operator generated by the considered problem.

  6. Multiple positive solutions for second order impulsive boundary value problems in Banach spaces

    Directory of Open Access Journals (Sweden)

    Zhi-Wei Lv

    2010-06-01

    Full Text Available By means of the fixed point index theory of strict set contraction operators, we establish new existence theorems on multiple positive solutions to a boundary value problem for second-order impulsive integro-differential equations with integral boundary conditions in a Banach space. Moreover, an application is given to illustrate the main result.

  7. Quality assurance tool for organ at risk delineation in radiation therapy using a parametric statistical approach.

    Science.gov (United States)

    Hui, Cheukkai B; Nourzadeh, Hamidreza; Watkins, William T; Trifiletti, Daniel M; Alonso, Clayton E; Dutta, Sunil W; Siebers, Jeffrey V

    2018-02-26

    To develop a quality assurance (QA) tool that identifies inaccurate organ at risk (OAR) delineations. The QA tool computed volumetric features from prior OAR delineation data from 73 thoracic patients to construct a reference database. All volumetric features of the OAR delineation are computed in three-dimensional space. Volumetric features of a new OAR are compared with respect to those in the reference database to discern delineation outliers. A multicriteria outlier detection system warns users of specific delineation outliers based on combinations of deviant features. Fifteen independent experimental sets including automatic, propagated, and clinically approved manual delineation sets were used for verification. The verification OARs included manipulations to mimic common errors. Three experts reviewed the experimental sets to identify and classify errors, first without; and then 1 week after with the QA tool. In the cohort of manual delineations with manual manipulations, the QA tool detected 94% of the mimicked errors. Overall, it detected 37% of the minor and 85% of the major errors. The QA tool improved reviewer error detection sensitivity from 61% to 68% for minor errors (P = 0.17), and from 78% to 87% for major errors (P = 0.02). The QA tool assists users to detect potential delineation errors. QA tool integration into clinical procedures may reduce the frequency of inaccurate OAR delineation, and potentially improve safety and quality of radiation treatment planning. © 2018 American Association of Physicists in Medicine.

  8. Automatic Delineation of On-Line Head-And-Neck Computed Tomography Images: Toward On-Line Adaptive Radiotherapy

    International Nuclear Information System (INIS)

    Zhang Tiezhi; Chi Yuwei; Meldolesi, Elisa; Yan Di

    2007-01-01

    Purpose: To develop and validate a fully automatic region-of-interest (ROI) delineation method for on-line adaptive radiotherapy. Methods and Materials: On-line adaptive radiotherapy requires a robust and automatic image segmentation method to delineate ROIs in on-line volumetric images. We have implemented an atlas-based image segmentation method to automatically delineate ROIs of head-and-neck helical computed tomography images. A total of 32 daily computed tomography images from 7 head-and-neck patients were delineated using this automatic image segmentation method. Manually drawn contours on the daily images were used as references in the evaluation of automatically delineated ROIs. Two methods were used in quantitative validation: (1) the dice similarity coefficient index, which indicates the overlapping ratio between the manually and automatically delineated ROIs; and (2) the distance transformation, which yields the distances between the manually and automatically delineated ROI surfaces. Results: Automatic segmentation showed agreement with manual contouring. For most ROIs, the dice similarity coefficient indexes were approximately 0.8. Similarly, the distance transformation evaluation results showed that the distances between the manually and automatically delineated ROI surfaces were mostly within 3 mm. The distances between two surfaces had a mean of 1 mm and standard deviation of <2 mm in most ROIs. Conclusion: With atlas-based image segmentation, it is feasible to automatically delineate ROIs on the head-and-neck helical computed tomography images in on-line adaptive treatments

  9. K Basin sludge packaging design criteria (PDC) and safety analysis report for packaging (SARP) approval plan

    International Nuclear Information System (INIS)

    Brisbin, S.A.

    1996-01-01

    This document delineates the plan for preparation, review, and approval of the Packaging Design Crieteria for the K Basin Sludge Transportation System and the Associated on-site Safety Analysis Report for Packaging. The transportation system addressed in the subject documents will be used to transport sludge from the K Basins using bulk packaging

  10. Tumor delineation: The weakest link in the search for accuracy in radiotherapy

    Directory of Open Access Journals (Sweden)

    Njeh C

    2008-01-01

    Full Text Available Radiotherapy is one of the most effective modalities for the treatment of cancer. However, there is a high degree of uncertainty associated with the target volume of most cancer sites. The sources of these uncertainties include, but are not limited to, the motion of the target, patient setup errors, patient movements, and the delineation of the target volume. Recently, many imaging techniques have been introduced to track the motion of tumors. The treatment delivery using these techniques is collectively called image-guided radiation therapy (IGRT. Ultimately, IGRT is only as good as the accuracy with which the target is known. There are reports of interobserver variability in tumor delineation across anatomical sites, but the widest ranges of variations have been reported for the delineation of head and neck tumors as well as esophageal and lung carcinomas. Significant interobserver variability in target delineation can be attributed to many factors including the impact of imaging and the influence of the observer (specialty, training, and personal bias. The visibility of the target can be greatly improved with the use of multimodality imaging by co-registration of CT with a second modality such as magnetic resonance imaging (MRI and/or positron emission tomography. Also, continuous education, training, and cross-collaboration of the radiation oncologist with other specialties can reduce the degree of variability in tumor delineation.

  11. On Existence of Solutions to the Caputo Type Fractional Order Three-Point Boundary Value Problems

    Directory of Open Access Journals (Sweden)

    B.M.B. Krushna

    2016-10-01

    Full Text Available In this paper, we establish the existence of solutions to the fractional order three-point boundary value problems by utilizing Banach contraction principle and Schaefer's fixed point theorem.

  12. A Damped Gauss-Newton Method for the Second-Order Cone Complementarity Problem

    International Nuclear Information System (INIS)

    Pan Shaohua; Chen, J.-S.

    2009-01-01

    We investigate some properties related to the generalized Newton method for the Fischer-Burmeister (FB) function over second-order cones, which allows us to reformulate the second-order cone complementarity problem (SOCCP) as a semismooth system of equations. Specifically, we characterize the B-subdifferential of the FB function at a general point and study the condition for every element of the B-subdifferential at a solution being nonsingular. In addition, for the induced FB merit function, we establish its coerciveness and provide a weaker condition than Chen and Tseng (Math. Program. 104:293-327, 2005) for each stationary point to be a solution, under suitable Cartesian P-properties of the involved mapping. By this, a damped Gauss-Newton method is proposed, and the global and superlinear convergence results are obtained. Numerical results are reported for the second-order cone programs from the DIMACS library, which verify the good theoretical properties of the method

  13. Crowdsourcing for error detection in cortical surface delineations.

    Science.gov (United States)

    Ganz, Melanie; Kondermann, Daniel; Andrulis, Jonas; Knudsen, Gitte Moos; Maier-Hein, Lena

    2017-01-01

    With the recent trend toward big data analysis, neuroimaging datasets have grown substantially in the past years. While larger datasets potentially offer important insights for medical research, one major bottleneck is the requirement for resources of medical experts needed to validate automatic processing results. To address this issue, the goal of this paper was to assess whether anonymous nonexperts from an online community can perform quality control of MR-based cortical surface delineations derived by an automatic algorithm. So-called knowledge workers from an online crowdsourcing platform were asked to annotate errors in automatic cortical surface delineations on 100 central, coronal slices of MR images. On average, annotations for 100 images were obtained in less than an hour. When using expert annotations as reference, the crowd on average achieves a sensitivity of 82 % and a precision of 42 %. Merging multiple annotations per image significantly improves the sensitivity of the crowd (up to 95 %), but leads to a decrease in precision (as low as 22 %). Our experiments show that the detection of errors in automatic cortical surface delineations generated by anonymous untrained workers is feasible. Future work will focus on increasing the sensitivity of our method further, such that the error detection tasks can be handled exclusively by the crowd and expert resources can be focused on error correction.

  14. Uniqueness for inverse problems of determining orders of multi-term time-fractional derivatives of diffusion equation

    OpenAIRE

    Li, Zhiyuan; Yamamoto, Masahiro

    2014-01-01

    This article proves the uniqueness for two kinds of inverse problems of identifying fractional orders in diffusion equations with multiple time-fractional derivatives by pointwise observation. By means of eigenfunction expansion and Laplace transform, we reduce the uniqueness for our inverse problems to the uniqueness of expansions of some special function and complete the proof.

  15. Boundary value problems for the 2nd-order Seiberg-Witten equations

    Directory of Open Access Journals (Sweden)

    Celso Melchiades Doria

    2005-02-01

    Full Text Available It is shown that the nonhomogeneous Dirichlet and Neuman problems for the 2nd-order Seiberg-Witten equation on a compact 4-manifold X admit a regular solution once the nonhomogeneous Palais-Smale condition ℋ is satisfied. The approach consists in applying the elliptic techniques to the variational setting of the Seiberg-Witten equation. The gauge invariance of the functional allows to restrict the problem to the Coulomb subspace 𝒞αℭ of configuration space. The coercivity of the 𝒮𝒲α-functional, when restricted into the Coulomb subspace, imply the existence of a weak solution. The regularity then follows from the boundedness of L∞-norms of spinor solutions and the gauge fixing lemma.

  16. Positive Solutions of Three-Order Delayed Periodic Boundary Value Problems

    Directory of Open Access Journals (Sweden)

    Na Wang

    2017-01-01

    Full Text Available Our main purpose is to consider the existence of positive solutions for three-order two-point boundary value problem in the following form: u′′′(t+ρ3u(t=f(t,u(t-τ,  0≤t≤2π,  u(i(0=u(i(2π,  i=1,2,  u(t=σ,  -τ≤t≤0, where σ,ρ, and τ are given constants satisfying τ∈(0,π/2. Some inequality conditions on ρ3u-f(t,u guaranteeing the existence and nonexistence of positive solutions are presented. Our discussion is based on the fixed point theorem in cones.

  17. 76 FR 36951 - In the Matter of Animal Cloning Sciences, Inc. (n/k/a Bancorp Energy, Inc.): Order of Suspension...

    Science.gov (United States)

    2011-06-23

    ... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] In the Matter of Animal Cloning Sciences, Inc. (n/k/a Bancorp Energy, Inc.): Order of Suspension of Trading June 21, 2011. It appears to the... securities of Animal Cloning Sciences, Inc. (n/k/a Bancorp Energy, Inc.) because it has not filed any...

  18. Delineating Concept Meanings: The Case of Terrorism.

    Science.gov (United States)

    Kleg, Milton; Mahlios, Marc

    1990-01-01

    Presents a teacher-initiated model for reaching class consensus on the meaning of confusing or interchangeable concepts in social studies classrooms. Illustrates the model by delineating terrorism. Shows procedural steps that involve students in self and small group interviews where definitions are clarified until consensus is reached. Suggests…

  19. Triple solutions for a Dirichlet boundary value problem involving a perturbed discrete p(k-Laplacian operator

    Directory of Open Access Journals (Sweden)

    Khaleghi Moghadam Mohsen

    2017-08-01

    Full Text Available Triple solutions are obtained for a discrete problem involving a nonlinearly perturbed one-dimensional p(k-Laplacian operator and satisfying Dirichlet boundary conditions. The methods for existence rely on a Ricceri-local minimum theorem for differentiable functionals. Several examples are included to illustrate the main results.

  20. Y2K

    OpenAIRE

    Stephanie Schmitt-Grohe; Martin Uribe

    1999-01-01

    This paper studies, within a general equilibrium model, the dynamics of Y2K-type shocks: anticipated, permanent losses in output whose magnitude can be lessened by investing resources in advance. The implied dynamics replicate three observed characteristics of those triggered by the Y2K bug: (1) Precautionary investment: investment in solving the Y2K problem begins before the year 2000; (2) Investment delay: although economic agents have been aware of the Y2K problem since the 1960s, investme...

  1. Analysis of the OECD main steam line break benchmark using ANC-K/MIDAC code

    International Nuclear Information System (INIS)

    Aoki, Shigeaki; Tahara, Yoshihisa; Suemura, Takayuki; Ogawa, Junto

    2004-01-01

    A three-dimensional (3D) neutronics and thermal-and-hydraulics (T/H) coupling code ANC-K/MIDAC has been developed. It is the combination of the 3D nodal kinetic code ANC-K and the 3D drift flux thermal hydraulic code MIDAC. In order to verify the adequacy of this code, we have performed several international benchmark problems. In this paper, we show the calculation results of ''OECD Main Steam Line Break Benchmark (MSLB benchmark)'', which gives the typical local power peaking problem. And we calculated the return-to-power scenario of the Phase II problem. The comparison of the results shows the very good agreement of important core parameters between the ANC-K/MIDAC and other participant codes. (author)

  2. A wavelet-based ECG delineation algorithm for 32-bit integer online processing.

    Science.gov (United States)

    Di Marco, Luigi Y; Chiari, Lorenzo

    2011-04-03

    Since the first well-known electrocardiogram (ECG) delineator based on Wavelet Transform (WT) presented by Li et al. in 1995, a significant research effort has been devoted to the exploitation of this promising method. Its ability to reliably delineate the major waveform components (mono- or bi-phasic P wave, QRS, and mono- or bi-phasic T wave) would make it a suitable candidate for efficient online processing of ambulatory ECG signals. Unfortunately, previous implementations of this method adopt non-linear operators such as root mean square (RMS) or floating point algebra, which are computationally demanding. This paper presents a 32-bit integer, linear algebra advanced approach to online QRS detection and P-QRS-T waves delineation of a single lead ECG signal, based on WT. The QRS detector performance was validated on the MIT-BIH Arrhythmia Database (sensitivity Se = 99.77%, positive predictive value P+ = 99.86%, on 109010 annotated beats) and on the European ST-T Database (Se = 99.81%, P+ = 99.56%, on 788050 annotated beats). The ECG delineator was validated on the QT Database, showing a mean error between manual and automatic annotation below 1.5 samples for all fiducial points: P-onset, P-peak, P-offset, QRS-onset, QRS-offset, T-peak, T-offset, and a mean standard deviation comparable to other established methods. The proposed algorithm exhibits reliable QRS detection as well as accurate ECG delineation, in spite of a simple structure built on integer linear algebra.

  3. Target volume delineation in external beam partial breast irradiation: Less inter-observer variation with preoperative- compared to postoperative delineation

    International Nuclear Information System (INIS)

    Leij, Femke van der; Elkhuizen, Paula H.M.; Janssen, Tomas M.; Poortmans, Philip; Sangen, Maurice van der; Scholten, Astrid N.; Vliet-Vroegindeweij, Corine van; Boersma, Liesbeth J.

    2014-01-01

    The challenge of adequate target volume definition in external beam partial breast irradiation (PBI) could be overcome with preoperative irradiation, due to less inter-observer variation. We compared the target volume delineation for external beam PBI on preoperative versus postoperative CT scans of twenty-four breast cancer patients

  4. An evaluation of automated GIS tools for delineating karst sinkholes and closed depressions from 1-meter LIDAR-derived digital elevation data

    Science.gov (United States)

    Doctor, Daniel H.; Young, John A.

    2013-01-01

    LiDAR (Light Detection and Ranging) surveys of karst terrains provide high-resolution digital elevation models (DEMs) that are particularly useful for mapping sinkholes. In this study, we used automated processing tools within ArcGIS (v. 10.0) operating on a 1.0 m resolution LiDAR DEM in order to delineate sinkholes and closed depressions in the Boyce 7.5 minute quadrangle located in the northern Shenandoah Valley of Virginia. The results derived from the use of the automated tools were then compared with depressions manually delineated by a geologist. Manual delineation of closed depressions was conducted using a combination of 1.0 m DEM hillshade, slopeshade, aerial imagery, and Topographic Position Index (TPI) rasters. The most effective means of visualizing depressions in the GIS was using an overlay of the partially transparent TPI raster atop the slopeshade raster at 1.0 m resolution. Manually identified depressions were subsequently checked using aerial imagery to screen for false positives, and targeted ground-truthing was undertaken in the field. The automated tools that were utilized include the routines in ArcHydro Tools (v. 2.0) for prescreening, evaluating, and selecting sinks and depressions as well as thresholding, grouping, and assessing depressions from the TPI raster. Results showed that the automated delineation of sinks and depressions within the ArcHydro tools was highly dependent upon pre-conditioning of the DEM to produce "hydrologically correct" surface flow routes. Using stream vectors obtained from the National Hydrologic Dataset alone to condition the flow routing was not sufficient to produce a suitable drainage network, and numerous artificial depressions were generated where roads, railways, or other manmade structures acted as flow barriers in the elevation model. Additional conditioning of the DEM with drainage paths across these barriers was required prior to automated 2delineation of sinks and depressions. In regions where the DEM

  5. Fermat collocation method for the solutions of nonlinear system of second order boundary value problems

    Directory of Open Access Journals (Sweden)

    Salih Yalcinbas

    2016-01-01

    Full Text Available In this study, a numerical approach is proposed to obtain approximate solutions of nonlinear system of second order boundary value problem. This technique is essentially based on the truncated Fermat series and its matrix representations with collocation points. Using the matrix method, we reduce the problem system of nonlinear algebraic equations. Numerical examples are also given to demonstrate the validity and applicability of the presented technique. The method is easy to implement and produces accurate results.

  6. Value of 18F-FDG PET-CT in nasopharyngeal carcinoma target delineation and radiotherapy boost

    International Nuclear Information System (INIS)

    Wang Ying; Feng Yanlin

    2011-01-01

    18 F-FDG PET-CT has widely used in nasopharyngeal carcinoma diagnosis and staging in recent years, it's effecten target volume delineation has received great attention. The article lays stress on the clinical research progress of 18 F-FDG PET-CT in the radiotherapy of nasopharyngeal carcinoma improve the accuracy of target delineation, reduce the difference of target delineation, guide the dose painting and boost. (authors)

  7. Tumour bed delineation for partial breast/breast boost radiotherapy: What is the optimal number of implanted markers?

    International Nuclear Information System (INIS)

    Kirby, Anna NM.; Jena, Rajesh; Harris, Emma J.; Evans, Phil M.; Crowley, Clare; Gregory, Deborah L.; Coles, Charlotte E.

    2013-01-01

    Purpose: International consensus has not been reached regarding the optimal number of implanted tumour bed (TB) markers for partial breast/breast boost radiotherapy target volume delineation. Four common methods are: insertion of 6 clips (4 radial, 1 deep and 1 superficial), 5 clips (4 radial and 1 deep), 1 clip at the chest wall, and no clips. We compared TB volumes delineated using 6, 5, 1 and 0 clips in women who have undergone wide-local excision (WLE) of breast cancer (BC) with full-thickness closure of the excision cavity, in order to determine the additional margin required for breast boost or partial breast irradiation (PBI) when fewer than 6 clips are used. Methods: Ten patients with invasive ductal BC who had undergone WLE followed by implantation of six fiducial markers (titanium clips) each underwent CT imaging for radiotherapy planning purposes. Retrospective processing of the DICOM image datasets was performed to remove markers and associated imaging artefacts, using an in-house software algorithm. Four observers outlined TB volumes on four different datasets for each case: (1) all markers present (CT 6M ); (2) the superficial marker removed (CT 5M ); (3) all but the chest wall marker removed (CT CW ); (4) all markers removed (CT 0M ). For each observer, the additional margin required around each of TB 0M , TB CW , and TB 5M in order to encompass TB 6M was calculated. The conformity level index (CLI) and differences in centre-of-mass (COM) between observers were quantified for CT 0M , CT CW , CT 5M , CT 6M . Results: The overall median additional margins required to encompass TB 6M were 8 mm (range 0–28 mm) for TB 0M , 5 mm (range 1–13 mm) for TB CW , and 2 mm (range 0–7 mm) for TB 5M . CLI were higher for TB volumes delineated using CT 6M (0.31) CT 5M (0.32) than for CT CW (0.19) and CT 0M (0.15). Conclusions: In women who have undergone WLE of breast cancer with full-thickness closure of the excision cavity and who are proceeding to PBI or

  8. Seasonally-managed wetland footprint delineation using Landsat ETM+ satellite imagery

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, Nigel W. T. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Epshtein, Olga [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Arizona State Univ., Tempe, AZ (United States). School of Sustainable Engineering and the Built Environment

    2014-01-09

    One major challenge in water resource management is the estimation of evapotranspiration losses from seasonally managed wetlands. Quantifying these losses is complicated by the dynamic nature of the wetlands' areal footprint during the periods of flood-up and drawdown. In this paper, we present a data-lean solution to this problem using an example application in the San Joaquin Basin, California. Through analysis of high-resolution Landsat Enhanced Thematic Mapper Plus (ETM+) satellite imagery, we develop a metric to better capture the extent of total flooded wetland area. The procedure is validated using year-long, continuously-logged field datasets for two wetlands within the study area. The proposed classification which uses a Landsat ETM + Band 5 (mid-IR wavelength) to Band 2 (visible green wavelength) ratio improves estimates by 30–50% relative to previous wetland delineation studies. Finally, requiring modest ancillary data, the study results provide a practical and efficient option for wetland management in data-sparse regions or un-gauged watersheds.

  9. Artificial Bee Colony Algorithm Based on K-Means Clustering for Multiobjective Optimal Power Flow Problem

    Directory of Open Access Journals (Sweden)

    Liling Sun

    2015-01-01

    Full Text Available An improved multiobjective ABC algorithm based on K-means clustering, called CMOABC, is proposed. To fasten the convergence rate of the canonical MOABC, the way of information communication in the employed bees’ phase is modified. For keeping the population diversity, the multiswarm technology based on K-means clustering is employed to decompose the population into many clusters. Due to each subcomponent evolving separately, after every specific iteration, the population will be reclustered to facilitate information exchange among different clusters. Application of the new CMOABC on several multiobjective benchmark functions shows a marked improvement in performance over the fast nondominated sorting genetic algorithm (NSGA-II, the multiobjective particle swarm optimizer (MOPSO, and the multiobjective ABC (MOABC. Finally, the CMOABC is applied to solve the real-world optimal power flow (OPF problem that considers the cost, loss, and emission impacts as the objective functions. The 30-bus IEEE test system is presented to illustrate the application of the proposed algorithm. The simulation results demonstrate that, compared to NSGA-II, MOPSO, and MOABC, the proposed CMOABC is superior for solving OPF problem, in terms of optimization accuracy.

  10. Delineating demographic units of woodland caribou (Rangifer tarandus caribou in Ontario: cautions and insights

    Directory of Open Access Journals (Sweden)

    Jennifer L. Shuter

    2012-03-01

    Full Text Available Delineating demographic structure across an organism’s range can reveal the extent to which population dynamics in different geographic areas are driven by local or external factors and can be crucial for effective conservation and management. Obtaining optimal data for such analyses can be time and resource-intensive and impending development and resource extraction pressures may necessitate the examination of existing data, even when they are less than ideal. We analyzed a historic telemetry dataset containing satellite radio-collar locations of 73 forest-dwelling woodland caribou in northern Ontario to determine demographic structure. We applied several clustering methods (i.e., agglomerative, divisive and fuzzy k-means to median seasonal locations. Results were used to distinguish demographic units and minimum convex polygons and fixed-kernel density estimates were used to delineate unit boundaries and core areas. For areas where sampling was considered representative of the distribution of caribou on the landscape, we assessed demographic distinctness by evaluating intra-individual variation in cluster membership, membership strength and distance between boundaries and core areas of adjacent units. The number and composition of clusters identified was similar among methods and caribou were grouped into 6 general clusters. The distinctions between the three clusters identified in the central portion of the province (i.e., Lac Seul, Wabakimi, Geraldton and the two clusters identified in the eastern portion of the province (i.e., Cochrane and Cochrane-Quebec were determined to represent demographic structuring. Additional distinctions in other areas (i.e., between The Red Lake and Lac Seul clusters in the west and between the central and eastern clusters may just be artifacts of the original sampling effort. Amongst demographic units, there was no evidence of individual flexibility in cluster membership and average membership strength was

  11. The condition, problems, and outlook on Ukraine accounting and control system of nuclear materials

    International Nuclear Information System (INIS)

    Galasun, O.

    1999-01-01

    There are 5 NPPs with 14 operating units in Ukraine as well as scientific facilities which are all under the IAEA safeguards. Although a number of important state laws concerning the use of nuclear energy and radiation safety there are still problems on computer processing of current information on accounting and control. The Y2K problem exists in relation to control and operating systems. Ukraine is ready to accept any recommendations in order to eliminate this problem. Some working groups were organised for solving the Y2K problem, each starting from different directions towards the common aim

  12. Our love-hate relationship with DNA barcodes, the Y2K problem, and the search for next generation barcodes

    Directory of Open Access Journals (Sweden)

    Jeffrey M. Marcus

    2018-01-01

    Full Text Available DNA barcodes are very useful for species identification especially when identification by traditional morphological characters is difficult. However, the short mitochondrial and chloroplast barcodes currently in use often fail to distinguish between closely related species, are prone to lateral transfer, and provide inadequate phylogenetic resolution, particularly at deeper nodes. The deficiencies of short barcode identifiers are similar to the deficiencies of the short year identifiers that caused the Y2K problem in computer science. The resolution of the Y2K problem was to increase the size of the year identifiers. The performance of conventional mitochondrial COI barcodes for phylogenetics was compared with the performance of complete mitochondrial genomes and nuclear ribosomal RNA repeats obtained by genome skimming for a set of caddisfly taxa (Insect Order Trichoptera. The analysis focused on Trichoptera Family Hydropsychidae, the net-spinning caddisflies, which demonstrates many of the frustrating limitations of current barcodes. To conduct phylogenetic comparisons, complete mitochondrial genomes (15 kb each and nuclear ribosomal repeats (9 kb each from six caddisfly species were sequenced, assembled, and are reported for the first time. These sequences were analyzed in comparison with eight previously published trichopteran mitochondrial genomes and two triochopteran rRNA repeats, plus outgroup sequences from sister clade Lepidoptera (butterflies and moths. COI trees were not well-resolved, had low bootstrap support, and differed in topology from prior phylogenetic analyses of the Trichoptera. Phylogenetic trees based on mitochondrial genomes or rRNA repeats were well-resolved with high bootstrap support and were largely congruent with each other. Because they are easily sequenced by genome skimming, provide robust phylogenetic resolution at various phylogenetic depths, can better distinguish between closely related species, and (in the

  13. Radio-anatomy Atlas for delineation SIRIADE web site: features and 1 year results

    International Nuclear Information System (INIS)

    Denisa, F.; Pointreau, Y.

    2010-01-01

    3-D conformal radiotherapy is based on accurate target volumes delineation. Radio-anatomy knowledge's are useful but sometimes difficult to obtain. Moreover, the sources of recommendations for volume definition are disparate. We thus developed a free radio-anatomy web site dedicated to volumes delineation for radiation-oncologists (www.siriade.org). This web site is a search engine allowing to access to delineation characteristics of main tumours illustrated with clinical cases. It does not aim to provide guidelines. Its main purpose is to provide an iconographic training support with frequent up-datings. We present the features of this web site and one year connexion statistics. (authors)

  14. Phantom study on three-dimensional target volume delineation by PET/CT-based auto-contouring

    International Nuclear Information System (INIS)

    Zhang, Tiejiao; Sakaguchi, Yuichi; Mitsumoto, Katsuhiko; Mitsumoto, Tatsuya; Sasaki, Masayuki; Tachiya, Yosuke; Ohya, Nobuyoshi

    2010-01-01

    The aim of this study was to determine an appropriate threshold value for delineation of the target volume in positron emission tomography (PET)/CT and to investigate whether we could delineate a target volume by phantom studies. A phantom consisted of six spheres (φ10-37 mm) filled with 18 F solution. Data acquisition was performed PET/CT in non-motion and motion status with high 18 F solution and in non-motion status with low 18 F solution. In non-motion phantom experiments, we determined two types of threshold value, an absolute SUV (T SUV ) and a percentage of the maximum SUV (T % ). Delineation using threshold values was applied for all spheres and for selected large spheres (a diameter of 22 mm or larger). In motion phantom experiments, data acquisition was performed in a static mode (sPET) and a gated mode (gPET). CT scanning was performed with helical CT (HCT) and 4-dimentional CT (4DCT). The appropriate threshold values were aT % =27% and aT SUV =2.4 for all spheres, and sT % =30% and sT SUV =4.3 for selected spheres. For all spheres in sPET/HCT in motion, the delineated volumes were 84%-129% by the aT % and 34%-127% by the aT SUV . In gPET/4DCT in motion, the delineated volumes were 94-103% by the aT % and 51-131% by the aT SUV . For low radioactivity spheres, the delineated volumes were all underestimated. A threshold value of T % =27% was proposed for auto-contouring of lung tumors. Our results also suggested that the respiratory gated data acquisition should be performed in both PET and CT for target volume delineation. (author)

  15. Stable Galerkin versus equal-order Galerkin least-squares elements for the stokes flow problem

    International Nuclear Information System (INIS)

    Franca, L.P.; Frey, S.L.; Sampaio, R.

    1989-11-01

    Numerical experiments are performed for the stokes flow problem employing a stable Galerkin method and a Galerkin/Least-squares method with equal-order elements. Error estimates for the methods tested herein are reviewed. The numerical results presented attest the good stability properties of all methods examined herein. (A.C.A.S.) [pt

  16. Observer variation in target volume delineation of lung cancer related to radiation oncologist-computer interaction: A 'Big Brother' evaluation

    International Nuclear Information System (INIS)

    Steenbakkers, Roel J.H.M.; Duppen, Joop C.; Fitton, Isabelle; Deurloo, Kirsten E.I.; Zijp, Lambert; Uitterhoeve, Apollonia L.J.; Rodrigus, Patrick T.R.; Kramer, Gijsbert W.P.; Bussink, Johan; Jaeger, Katrien De; Belderbos, Jose S.A.; Hart, Augustinus A.M.; Nowak, Peter J.C.M.; Herk, Marcel van; Rasch, Coen R.N.

    2005-01-01

    Background and purpose: To evaluate the process of target volume delineation in lung cancer for optimization of imaging, delineation protocol and delineation software. Patients and methods: Eleven radiation oncologists (observers) from five different institutions delineated the Gross Tumor Volume (GTV) including positive lymph nodes of 22 lung cancer patients (stages I-IIIB) on CT only. All radiation oncologist-computer interactions were recorded with a tool called 'Big Brother'. For each radiation oncologist and patient the following issues were analyzed: delineation time, number of delineated points and corrections, zoom levels, level and window (L/W) settings, CT slice changes, use of side windows (coronal and sagittal) and software button use. Results: The mean delineation time per GTV was 16 min (SD 10 min). The mean delineation time for lymph node positive patients was on average 3 min larger (P=0.02) than for lymph node negative patients. Many corrections (55%) were due to L/W change (e.g. delineating in mediastinum L/W and then correcting in lung L/W). For the lymph node region, a relatively large number of corrections was found (3.7 corr/cm 2 ), indicating that it was difficult to delineate lymph nodes. For the tumor-atelectasis region, a relative small number of corrections was found (1.0 corr/cm 2 ), indicating that including or excluding atelectasis into the GTV was a clinical decision. Inappropriate use of L/W settings was frequently found (e.g. 46% of all delineated points in the tumor-lung region were delineated in mediastinum L/W settings). Despite a large observer variation in cranial and caudal direction of 0.72 cm (1 SD), the coronal and sagittal side windows were not used in 45 and 60% of the cases, respectively. For the more difficult cases, observer variation was smaller when the coronal and sagittal side windows were used. Conclusions: With the 'Big Brother' tool a method was developed to trace the delineation process. The differences between

  17. Dynamics of second order rational difference equations with open problems and conjectures

    CERN Document Server

    Kulenovic, Mustafa RS

    2001-01-01

    This self-contained monograph provides systematic, instructive analysis of second-order rational difference equations. After classifying the various types of these equations and introducing some preliminary results, the authors systematically investigate each equation for semicycles, invariant intervals, boundedness, periodicity, and global stability. Of paramount importance in their own right, the results presented also offer prototypes towards the development of the basic theory of the global behavior of solutions of nonlinear difference equations of order greater than one. The techniques and results in this monograph are also extremely useful in analyzing the equations in the mathematical models of various biological systems and other applications. Each chapter contains a section of open problems and conjectures that will stimulate further research interest in working towards a complete understanding of the dynamics of the equation and its functional generalizations-many of them ideal for research project...

  18. Radio-anatomy Atlas for delineation SIRIADE web site: features and 1 year results; Site de radio-anatomie et d'aide a la delineation (SIRIADE): presentation et bilan a un an

    Energy Technology Data Exchange (ETDEWEB)

    Denisa, F. [Centre Jean-Bernard, Clinique Victor-Hugo, 72 - Le Mans (France); Pointreau, Y. [Clinique d' oncologie radiotherapie, Centre Henry-S.-Kaplan, CHU Bretonneau, 37 - Tours (France)

    2010-07-01

    3-D conformal radiotherapy is based on accurate target volumes delineation. Radio-anatomy knowledge's are useful but sometimes difficult to obtain. Moreover, the sources of recommendations for volume definition are disparate. We thus developed a free radio-anatomy web site dedicated to volumes delineation for radiation-oncologists (www.siriade.org). This web site is a search engine allowing to access to delineation characteristics of main tumours illustrated with clinical cases. It does not aim to provide guidelines. Its main purpose is to provide an iconographic training support with frequent up-datings. We present the features of this web site and one year connexion statistics. (authors)

  19. EVALUATION OF CATROSAT 1PAN STEREO AND RESOURCESAT LISS 4 MSS MERGED DATA FOR MORPHOMETRIC ANALYSIS, DELINEATION OF DRAINAGE BASINS AND CODIFICATION IN TAMIL NADU, INDIA AND AUSTRALIA

    Directory of Open Access Journals (Sweden)

    G. S. Mohamed

    2012-07-01

    Full Text Available The Topographic maps and Aerial Photographs are used for morphometric analysis of drainage basins and mapping contours with drainage. The stereo pairs of 2.5 m resolution Cartosat 1, Indian satellite 2 and merged data with 5.5 m resolution P6 Resourcesat 1 LISS 4 Indian satellite of 2001 is used to map, rills, gullies, and streams of first order to evaluate part of drainage basin of Cooum and Poondi Reservoir in Thiruvallur taluk of Tamil Nadu state. The Geo Eye latest 2011data is also used with Catrosat 1Stereo data to study present morphology of tiny micro watersheds to study the use of High resolution data for delineation and codification of watersheds. This study area is in an inter fluvial drainage basin of Cooum and Kusasthalai rivers. Kusasthalai river drains in Poondi reservoir which is about 50 km from Chennai. The excess water from Kosasthalai is also diverted through Kesawaram weir to Cooum river which passes through Thiruvallur and Chennai city before it's confluence with Bay of Benegal in the east. As Cooum basin is at higher elevation, water for irrigation is again diverted through chain of tanks to Kusasthalai river basin to drain in Poondi reservoir. Delineation of water sheds in this fluvial basin is difficult by manual survey as man made irrigation channels, natural drainage streams etc., have to be clearly identified. The streams of various orders are identified based on Strahler stream order hierarchy of tributaries, slops and contours using large scale satellite data. The micro water sheds are delinated identifying the ridges from Catrosat data for this interfluves basin which has mild slop. To illustrate this research, parts of two micro watersheds which were delineated using 1:50000 data for Tamil Nadu watershed Atlas up to 7th order streams are taken up for a detailed study using high resolution data. 19 Micro watersheds with streams up to 10th order are mapped. The capability of high resolution satellite data for digital

  20. Topological regularizations of the triple collision singularity in the 3-vortex problem

    International Nuclear Information System (INIS)

    Hiraoka, Yasuaki

    2008-01-01

    The triple collision singularity in the 3-vortex problem is studied in this paper. Under the necessary condition k 1 -1 +k 2 -1 +k 3 -1 =0 for vorticities to have the triple collision, the main results are summarized as follows: (i) For k 1 = k 2 , the triple collision singularity is topologically regularizable. (ii) For 0 1 − k 2 | < ε with a sufficiently small ε, the triple collision singularity is not topologically regularizable. First of all, in order to prove these statements, all singularities in the 3-vortex problem are classified. Then, we introduce a dynamical system by blowing up the triple collision singularity with an appropriate time scaling. Roughly speaking, it corresponds to pasting an invariant manifold at the triple collision singularity on the original phase space. This technique is well known as McGehee's collision manifold (1974 Inventions Math. 27 191–227) in the N-body problem of celestial mechanics. Finally, by adopting the viewpoint of Easton (1971 J. Diff. Eqns 10 92–9), topological regularizations of the triple collision singularity are studied in detail

  1. Modular Transformations, Order-Chaos Transitions and Pseudo-Random Number Generation

    Science.gov (United States)

    Bonelli, Antonio; Ruffo, Stefano

    Successive pairs of pseudo-random numbers generated by standard linear congruential transformations display ordered patterns of parallel lines. We study the "ordered" and "chaotic" distribution of such pairs by solving the eigenvalue problem for two-dimensional modular transformations over integers. We conjecture that the optimal uniformity for pair distribution is obtained when the slope of linear modular eigenspaces takes the value n opt =maxint (p/√ {p-1}), where p is a prime number. We then propose a new generator of pairs of independent pseudo-random numbers, which realizes an optimal uniform distribution (in the "statistical" sense) of points on the unit square (0, 1] × (0, 1]. The method can be easily generalized to the generation of k-tuples of random numbers (with k>2).

  2. Using aquatic invertebrates to delineate seasonal and temporary wetlands in the Prairie Pothole Region of North America

    Science.gov (United States)

    Euliss, Ned H.; Mushet, David M.; Johnson, Douglas H.

    2002-01-01

    Tillage can destroy or greatly disturb indicators of hydric soils and hydrophytic vegetation, making delineation of tilled wetlands difficult. The remains of aquatic invertebrates (e.g., shells, drought-resistant eggs, and trichopteran cases) are easily identifiable and persist in wetland substrates even when wetlands are dry. Additionally, these remains are not easily destroyed by mechanical tillage. To test the feasibility of using invertebrate remains to delineate wetlands, we used two methods to identify the wetland edge of ten seasonal and ten temporary wetlands, evenly divided between grassland and cropland landscapes. First, we identified the wetland edge using hydric soil and vegetation indicators along six evenly spaced transects in each wetland (our “standard” delineation). We then identified the wetland edge along the same transects using aquatic invertebrate remains as our indicator. In grassland landscapes, delineations of the wetland edge made using invertebrate remains were consistently at the same location or closer to the wetland center as the standard delineations for both seasonal and temporary wetlands. In cropland landscapes, however, many of our invertebrate delineations of seasonal and temporary wetlands were on the upland side of our standard delineations. We attribute the differences to movement of remains during tillage, increased maximum pool levels in cropland wetlands, and disturbance of hydric soils and plants. We found that the elevations of the wetland edge indicated by invertebrate remains were more consistent within a wetland than elevations determined by standard delineations. Aquatic invertebrate remains can be useful in delineating wetlands when other indicators have been destroyed or severely disturbed by tillage.

  3. The focal boundary value problem for strongly singular higher-order nonlinear functional-differential equations

    Czech Academy of Sciences Publication Activity Database

    Mukhigulashvili, Sulkhan; Půža, B.

    2015-01-01

    Roč. 2015, January (2015), s. 17 ISSN 1687-2770 Institutional support: RVO:67985840 Keywords : higher order nonlinear functional-differential equations * two-point right-focal boundary value problem * strong singularity Subject RIV: BA - General Mathematics Impact factor: 0.642, year: 2015 http://link.springer.com/article/10.1186%2Fs13661-014-0277-1

  4. Monotone methods for solving a boundary value problem of second order discrete system

    Directory of Open Access Journals (Sweden)

    Wang Yuan-Ming

    1999-01-01

    Full Text Available A new concept of a pair of upper and lower solutions is introduced for a boundary value problem of second order discrete system. A comparison result is given. An existence theorem for a solution is established in terms of upper and lower solutions. A monotone iterative scheme is proposed, and the monotone convergence rate of the iteration is compared and analyzed. The numerical results are given.

  5. Automated volume of interest delineation and rendering of cone beam CT images in interventional cardiology

    Science.gov (United States)

    Lorenz, Cristian; Schäfer, Dirk; Eshuis, Peter; Carroll, John; Grass, Michael

    2012-02-01

    Interventional C-arm systems allow the efficient acquisition of 3D cone beam CT images. They can be used for intervention planning, navigation, and outcome assessment. We present a fast and completely automated volume of interest (VOI) delineation for cardiac interventions, covering the whole visceral cavity including mediastinum and lungs but leaving out rib-cage and spine. The problem is addressed in a model based approach. The procedure has been evaluated on 22 patient cases and achieves an average surface error below 2mm. The method is able to cope with varying image intensities, varying truncations due to the limited reconstruction volume, and partially with heavy metal and motion artifacts.

  6. Enhancing students' higher order thinking skills through computer-based scaffolding in problem-based learning

    Science.gov (United States)

    Kim, Nam Ju

    This multiple paper dissertation addressed several issues in Problem-based learning (PBL) through conceptual analysis, meta-analysis, and empirical research. PBL is characterized by ill-structured tasks, self-directed learning process, and a combination of individual and cooperative learning activities. Students who lack content knowledge and problem-solving skills may struggle to address associated tasks that are beyond their current ability levels in PBL. This dissertation addressed a) scaffolding characteristics (i.e., scaffolding types, delivery method, customization) and their effects on students' perception of optimal challenge in PBL, b) the possibility of virtual learning environments for PBL, and c) the importance of information literacy for successful PBL learning. Specifically, this dissertation demonstrated the effectiveness of scaffolding customization (i.e., fading, adding, and fading/adding) to enhance students' self-directed learning in PBL. Moreover, the effectiveness of scaffolding was greatest when scaffolding customization is self-selected than based on fixed-time interval and their performance. This suggests that it might be important for students to take responsibility for their learning in PBL and individualized and just-in-time scaffolding can be one of the solutions to address K-12 students' difficulties in improving problem-solving skills and adjusting to PBL.

  7. Uniqueness of global quasi-classical solutions of the Cauchy problems for first-order nonlinear partial differential equations

    International Nuclear Information System (INIS)

    Tran Duc Van

    1994-01-01

    The notion of global quasi-classical solutions of the Cauchy problems for first-order nonlinear partial differential equations is presented, some uniqueness theorems and a stability result are established by the method based on the theory of differential inclusions. In particular, the answer to an open problem of S.N. Kruzhkov is given. (author). 10 refs, 1 fig

  8. An automatic, stagnation point based algorithm for the delineation of Wellhead Protection Areas

    Science.gov (United States)

    Tosco, Tiziana; Sethi, Rajandrea; di Molfetta, Antonio

    2008-07-01

    Time-related capture areas are usually delineated using the backward particle tracking method, releasing circles of equally spaced particles around each well. In this way, an accurate delineation often requires both a very high number of particles and a manual capture zone encirclement. The aim of this work was to propose an Automatic Protection Area (APA) delineation algorithm, which can be coupled with any model of flow and particle tracking. The computational time is here reduced, thanks to the use of a limited number of nonequally spaced particles. The particle starting positions are determined coupling forward particle tracking from the stagnation point, and backward particle tracking from the pumping well. The pathlines are postprocessed for a completely automatic delineation of closed perimeters of time-related capture zones. The APA algorithm was tested for a two-dimensional geometry, in homogeneous and nonhomogeneous aquifers, steady state flow conditions, single and multiple wells. Results show that the APA algorithm is robust and able to automatically and accurately reconstruct protection areas with a very small number of particles, also in complex scenarios.

  9. K/AR dating of clinoptilolite, mordenite, and associated clays from Yucca Mountains, Nevada

    International Nuclear Information System (INIS)

    WoldeGabriel, G.

    1993-01-01

    Zeolites are abundant in the geologic record in both continental and marine environments. The purpose of the present study is to evaluate the utility of K-bearing zeolites for dating by the K/Ar method to determine the time of zeolite diagenesis at Yucca Mountain, Nevada (Fig. 1). At Yucca Mountain, K-rich clinoptilolite and possibly mordenite are the only potentially K/Ar dateable secondary minerals present in the zeolite-rich tuffs except for some illite/smectites (≥10% illite layers) associated with these minerals. Direct dating of K-rich clinoptilolite, the most abundant zeolite in the altered tuffs, is important to delineate zeolite chronology as part of the site characterization of Yucca Mountain

  10. Image-Based Delineation and Classification of Built Heritage Masonry

    Directory of Open Access Journals (Sweden)

    Noelia Oses

    2014-02-01

    Full Text Available Fundación Zain is developing new built heritage assessment protocols. The goal is to objectivize and standardize the analysis and decision process that leads to determining the degree of protection of built heritage in the Basque Country. The ultimate step in this objectivization and standardization effort will be the development of an information and communication technology (ICT tool for the assessment of built heritage. This paper presents the ground work carried out to make this tool possible: the automatic, image-based delineation of stone masonry. This is a necessary first step in the development of the tool, as the built heritage that will be assessed consists of stone masonry construction, and many of the features analyzed can be characterized according to the geometry and arrangement of the stones. Much of the assessment is carried out through visual inspection. Thus, this process will be automated by applying image processing on digital images of the elements under inspection. The principal contribution of this paper is the automatic delineation the framework proposed. The other contribution is the performance evaluation of this delineation as the input to a classifier for a geometrically characterized feature of a built heritage object. The element chosen to perform this evaluation is the stone arrangement of masonry walls. The validity of the proposed framework is assessed on real images of masonry walls.

  11. Colourings of (k-r,k-trees

    Directory of Open Access Journals (Sweden)

    M. Borowiecki

    2017-01-01

    Full Text Available Trees are generalized to a special kind of higher dimensional complexes known as \\((j,k\\-trees ([L. W. Beineke, R. E. Pippert, On the structure of \\((m,n\\-trees, Proc. 8th S-E Conf. Combinatorics, Graph Theory and Computing, 1977, 75-80], and which are a natural extension of \\(k\\-trees for \\(j=k-1\\. The aim of this paper is to study\\((k-r,k\\-trees ([H. P. Patil, Studies on \\(k\\-trees and some related topics, PhD Thesis, University of Warsaw, Poland, 1984], which are a generalization of \\(k\\-trees (or usual trees when \\(k=1\\. We obtain the chromatic polynomial of \\((k-r,k\\-trees and show that any two \\((k-r,k\\-trees of the same order are chromatically equivalent. However, if \\(r\

  12. Delineation of wetland areas from high resolution WorldView-2 data by object-based method

    International Nuclear Information System (INIS)

    Hassan, N; Hamid, J R A; Adnan, N A; Jaafar, M

    2014-01-01

    Various classification methods are available that can be used to delineate land cover types. Object-based is one of such methods for delineating the land cover from satellite imageries. This paper focuses on the digital image processing aspects of discriminating wetland areas via object-based method using high resolution satellite multispectral WorldView-2 image data taken over part of Penang Island region. This research is an attempt to improve the wetland area delineation in conjunction with a range of classification techniques which can be applied to satellite data with high spatial and spectral resolution such as World View 2. The intent is to determine a suitable approach to delineate and map these wetland areas more appropriately. There are common parameters to take into account that are pivotal in object-based method which are the spatial resolution and the range of spectral channels of the imaging sensor system. The preliminary results of the study showed object-based analysis is capable of delineating wetland region of interest with an accuracy that is acceptable to the required tolerance for land cover classification

  13. On Some Pursuit and Evasion Differential Game Problems for an Infinite Number of First-Order Differential Equations

    Directory of Open Access Journals (Sweden)

    Abbas Badakaya Ja'afaru

    2012-01-01

    Full Text Available We study pursuit and evasion differential game problems described by infinite number of first-order differential equations with function coefficients in Hilbert space l2. Problems involving integral, geometric, and mix constraints to the control functions of the players are considered. In each case, we give sufficient conditions for completion of pursuit and for which evasion is possible. Consequently, strategy of the pursuer and control function of the evader are constructed in an explicit form for every problem considered.

  14. A study of prostate delineation referenced against a gold standard created from the visible human data

    International Nuclear Information System (INIS)

    Gao Zhanrong; Wilkins, David; Eapen, Libni; Morash, Christopher; Wassef, Youssef; Gerig, Lee

    2007-01-01

    Purpose: To measure inter- and intra-observer variation and systematic error in CT based prostate delineation, where individual delineations are referenced against a gold standard produced from photographic anatomical images from the Visible Human Project (VHP). Materials and methods: The CT and anatomical images of the VHP male form the basic data set for this study. The gold standard was established based on 1 mm thick anatomical photographic images. These were registered against the 3 mm thick CT images that were used for target delineation. A total of 120 organ delineations were performed by six radiation oncologists. Results: The physician delineated prostate volume was on average 30% larger than the 'true' prostate volume, but on average included only 84% of the gold standard volume. Our study found a systematic delineation error such that posterior portions of the prostate were always missed while anteriorly some normal tissue was always defined as target. Conclusions: Our data suggest that radiation oncologists are more concerned with the unintentional inclusion of rectal tissue than they are in missing prostate volume. In contrast, they are likely to overextend the anterior boundary of the prostate to encompass normal tissue such as the bladder

  15. Development of Open-Ended Problems for Measuring The Higher-Order-Thinking-Skills of High School Students on Global Warming Phenomenon

    Science.gov (United States)

    Fianti; Najwa, F. L.; Linuwih, S.

    2017-04-01

    Higher-order-thinking-skills can not be developed directly, except by training which is employing open-ended problems for measuring and developing critics, creativeness, and problem-solving thinking-skills of students. This study is a research and development producing open-ended problems. The purpose of this study is to measure the properness and effectiveness of the developed product and to observe the profile of higher-order-thinking-skills of students on global warming phenomenon. The result of properness test of open-ended problems according to the experts is 92,59% on the first stage and 97,53% on the second stage, so we can assume that the product isvery proper. The result of effectiveness test shows the coefficient of correlation between student’s midterm test scores and open-ended questions is 0,634 which is in the category of strong. Higher-order-thinking-skills of SMA Negeri 1 Salatiga students is in the category of good with the average achievement scores 61,28.

  16. Delineating Hydrofacies Spatial Distribution by Integrating Ensemble Data Assimilation and Indicator Geostatistics

    Energy Technology Data Exchange (ETDEWEB)

    Song, Xuehang [Florida State Univ., Tallahassee, FL (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chen, Xingyuan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ye, Ming [Florida State Univ., Tallahassee, FL (United States); Dai, Zhenxue [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hammond, Glenn Edward [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-07-01

    This study develops a new framework of facies-based data assimilation for characterizing spatial distribution of hydrofacies and estimating their associated hydraulic properties. This framework couples ensemble data assimilation with transition probability-based geostatistical model via a parameterization based on a level set function. The nature of ensemble data assimilation makes the framework efficient and flexible to be integrated with various types of observation data. The transition probability-based geostatistical model keeps the updated hydrofacies distributions under geological constrains. The framework is illustrated by using a two-dimensional synthetic study that estimates hydrofacies spatial distribution and permeability in each hydrofacies from transient head data. Our results show that the proposed framework can characterize hydrofacies distribution and associated permeability with adequate accuracy even with limited direct measurements of hydrofacies. Our study provides a promising starting point for hydrofacies delineation in complex real problems.

  17. Phylogenetic reconstruction in the order Nymphaeales: ITS2 secondary structure analysis and in silico testing of maturase k (matK) as a potential marker for DNA bar coding.

    Science.gov (United States)

    Biswal, Devendra Kumar; Debnath, Manish; Kumar, Shakti; Tandon, Pramod

    2012-01-01

    The Nymphaeales (waterlilly and relatives) lineage has diverged as the second branch of basal angiosperms and comprises of two families: Cabombaceae and Nymphaceae. The classification of Nymphaeales and phylogeny within the flowering plants are quite intriguing as several systems (Thorne system, Dahlgren system, Cronquist system, Takhtajan system and APG III system (Angiosperm Phylogeny Group III system) have attempted to redefine the Nymphaeales taxonomy. There have been also fossil records consisting especially of seeds, pollen, stems, leaves and flowers as early as the lower Cretaceous. Here we present an in silico study of the order Nymphaeales taking maturaseK (matK) and internal transcribed spacer (ITS2) as biomarkers for phylogeny reconstruction (using character-based methods and Bayesian approach) and identification of motifs for DNA barcoding. The Maximum Likelihood (ML) and Bayesian approach yielded congruent fully resolved and well-supported trees using a concatenated (ITS2+ matK) supermatrix aligned dataset. The taxon sampling corroborates the monophyly of Cabombaceae. Nuphar emerges as a monophyletic clade in the family Nymphaeaceae while there are slight discrepancies in the monophyletic nature of the genera Nymphaea owing to Victoria-Euryale and Ondinea grouping in the same node of Nymphaeaceae. ITS2 secondary structures alignment corroborate the primary sequence analysis. Hydatellaceae emerged as a sister clade to Nymphaeaceae and had a basal lineage amongst the water lilly clades. Species from Cycas and Ginkgo were taken as outgroups and were rooted in the overall tree topology from various methods. MatK genes are fast evolving highly variant regions of plant chloroplast DNA that can serve as potential biomarkers for DNA barcoding and also in generating primers for angiosperms with identification of unique motif regions. We have reported unique genus specific motif regions in the Order Nymphaeles from matK dataset which can be further validated for

  18. Geometrical Comparison Measures for Tumor Delineation, what do they mean for the Actual Dosis Plan?

    DEFF Research Database (Denmark)

    Hollensen, Christian; Persson, G.; Højgaard, L.

    2012-01-01

    Purpose/Objective: Gross tumour volume (GTV) delineation is central for radiotherapy planning. It provides the basis of the clinical target volume and finally the planning target volume (PTV) which is used for dose optimization. GTV delineations are prone to intermethod and inter......observer variation. In clinical studies this variation is commonly represented by geometrical volume comparison measures (GVCMs) as volume assessment, centre of mass and overlap. The correlation between these measures and the radiotherapy plan are however unclear. The aim of the present study is to investigate...... the correlation between GVCMs and the radiotherapy plans of patients with peripheral lung tumours. Materials and Methods: Peripheral lung tumours of 10 patients referred for stereotactic body radiotherapy in 2008 were delineated by 3 radiologists and 3 oncologists. From these GTV delineations 6 different...

  19. Differences in delineation guidelines for head and neck cancer result in inconsistent reported dose and corresponding NTCP

    International Nuclear Information System (INIS)

    Brouwer, Charlotte L.; Steenbakkers, Roel J.H.M.; Gort, Elske; Kamphuis, Marije E.; Laan, Hans Paul van der; Veld, Aart A. van’t; Sijtsema, Nanna M.; Langendijk, Johannes A.

    2014-01-01

    Purpose: To test the hypothesis that delineation of swallowing organs at risk (SWOARs) based on different guidelines results in differences in dose–volume parameters and subsequent normal tissue complication probability (NTCP) values for dysphagia-related endpoints. Materials and methods: Nine different SWOARs were delineated according to five different delineation guidelines in 29 patients. Reference delineation was performed according to the guidelines and NTCP-models of Christianen et al. Concordance Index (CI), dosimetric consequences, as well as differences in the subsequent NTCPs were calculated. Results: The median CI of the different delineation guidelines with the reference guidelines was 0.54 for the pharyngeal constrictor muscles, 0.56 for the laryngeal structures and 0.07 for the cricopharyngeal muscle and esophageal inlet muscle. The average difference in mean dose to the SWOARs between the guidelines with the largest difference (maxΔD) was 3.5 ± 3.2 Gy. A mean ΔNTCP of 2.3 ± 2.7% was found. For two patients, ΔNTCP exceeded 10%. Conclusions: The majority of the patients showed little differences in NTCPs between the different delineation guidelines. However, large NTCP differences >10% were found in 7% of the patients. For correct use of NTCP models in individual patients, uniform delineation guidelines are of great importance

  20. An interior-point method for the Cartesian P*(k-linear complementarity problem over symmetric cones

    Directory of Open Access Journals (Sweden)

    B Kheirfam

    2014-06-01

    Full Text Available A novel primal-dual path-following interior-point algorithm for the Cartesian P*(k-linear complementarity problem over symmetric cones is presented. The algorithm is based on a reformulation of the central path for finding the search directions. For a full Nesterov-Todd step feasible interior-point algorithm based on the new search directions, the complexity bound of the algorithm with small-update approach is the best-available bound.

  1. Application of power series to the solution of the boundary value problem for a second order nonlinear differential equation

    International Nuclear Information System (INIS)

    Semenova, V.N.

    2016-01-01

    A boundary value problem for a nonlinear second order differential equation has been considered. A numerical method has been proposed to solve this problem using power series. Results of numerical experiments have been presented in the paper [ru

  2. Delineating social network data anonymization via random edge perturbation

    KAUST Repository

    Xue, Mingqiang; Karras, Panagiotis; Raï ssi, Chedy; Kalnis, Panos; Pung, Hungkeng

    2012-01-01

    study of the probability of success of any}structural attack as a function of the perturbation probability. Our analysis provides a powerful tool for delineating the identification risk of perturbed social network data; our extensive experiments

  3. On sign constant solutions of certain boundary value problems for second-order functional differential equations

    Czech Academy of Sciences Publication Activity Database

    Lomtatidze, Alexander; Vodstrčil, Petr

    2005-01-01

    Roč. 84, č. 2 (2005), s. 197-209 ISSN 0003-6811 Institutional research plan: CEZ:AV0Z10190503 Keywords : second order linear functional differential equations * nonnegative solution * two-point boundary value problem Subject RIV: BA - General Mathematics http://www.tandfonline.com/doi/full/10.1080/00036810410001724427

  4. A Third-Order p-Laplacian Boundary Value Problem Solved by an SL(3,ℝ Lie-Group Shooting Method

    Directory of Open Access Journals (Sweden)

    Chein-Shan Liu

    2013-01-01

    Full Text Available The boundary layer problem for power-law fluid can be recast to a third-order p-Laplacian boundary value problem (BVP. In this paper, we transform the third-order p-Laplacian into a new system which exhibits a Lie-symmetry SL(3,ℝ. Then, the closure property of the Lie-group is used to derive a linear transformation between the boundary values at two ends of a spatial interval. Hence, we can iteratively solve the missing left boundary conditions, which are determined by matching the right boundary conditions through a finer tuning of r∈[0,1]. The present SL(3,ℝ Lie-group shooting method is easily implemented and is efficient to tackle the multiple solutions of the third-order p-Laplacian. When the missing left boundary values can be determined accurately, we can apply the fourth-order Runge-Kutta (RK4 method to obtain a quite accurate numerical solution of the p-Laplacian.

  5. Polarized-neutron-scattering study of the spin-wave excitations in the 3-k ordered phase of uranium antimonide.

    Science.gov (United States)

    Magnani, N; Caciuffo, R; Lander, G H; Hiess, A; Regnault, L-P

    2010-03-24

    The anisotropy of magnetic fluctuations propagating along the [1 1 0] direction in the ordered phase of uranium antimonide has been studied using polarized inelastic neutron scattering. The observed polarization behavior of the spin waves is a natural consequence of the longitudinal 3-k magnetic structure; together with recent results on the 3-k-transverse uranium dioxide, these findings establish this technique as an important tool to study complex magnetic arrangements. Selected details of the magnon excitation spectra of USb have also been reinvestigated, indicating the need to revise the currently accepted theoretical picture for this material.

  6. Maximum Principles and Boundary Value Problems for First-Order Neutral Functional Differential Equations

    Directory of Open Access Journals (Sweden)

    Domoshnitsky Alexander

    2009-01-01

    Full Text Available We obtain the maximum principles for the first-order neutral functional differential equation where , and are linear continuous operators, and are positive operators, is the space of continuous functions, and is the space of essentially bounded functions defined on . New tests on positivity of the Cauchy function and its derivative are proposed. Results on existence and uniqueness of solutions for various boundary value problems are obtained on the basis of the maximum principles.

  7. LSODE, 1. Order Stiff or Non-Stiff Ordinary Differential Equations System Initial Value Problems

    International Nuclear Information System (INIS)

    Hindmarsh, A.C.; Petzold, L.R.

    2005-01-01

    1 - Description of program or function: LSODE (Livermore Solver for Ordinary Differential Equations) solves stiff and non-stiff systems of the form dy/dt = f. In the stiff case, it treats the Jacobian matrix df/dy as either a dense (full) or a banded matrix, and as either user-supplied or internally approximated by difference quotients. It uses Adams methods (predictor-corrector) in the non-stiff case, and Backward Differentiation Formula (BDF) methods (the Gear methods) in the stiff case. The linear systems that arise are solved by direct methods (LU factor/solve). The LSODE source is commented extensively to facilitate modification. Both a single-precision version and a double-precision version are available. 2 - Methods: It is assumed that the ODEs are given explicitly, so that the system can be written in the form dy/dt = f(t,y), where y is the vector of dependent variables, and t is the independent variable. LSODE contains two variable-order, variable- step (with interpolatory step-changing) integration methods. The first is the implicit Adams or non-stiff method, of orders one through twelve. The second is the backward differentiation or stiff method (or BDF method, or Gear's method), of orders one through five. 3 - Restrictions on the complexity of the problem: The differential equations must be given in explicit form, i.e., dy/dt = f(y,t). Problems with intermittent high-speed transients may cause inefficient or unstable performance

  8. PURA syndrome: clinical delineation and genotype-phenotype study in 32 individuals with review of published literature

    Science.gov (United States)

    Reijnders, Margot R F; Janowski, Robert; Alvi, Mohsan; Self, Jay E; van Essen, Ton J; Vreeburg, Maaike; Rouhl, Rob P W; Stevens, Servi J C; Stegmann, Alexander P A; Schieving, Jolanda; Pfundt, Rolph; van Dijk, Katinke; Smeets, Eric; Stumpel, Connie T R M; Bok, Levinus A; Cobben, Jan Maarten; Engelen, Marc; Mansour, Sahar; Whiteford, Margo; Chandler, Kate E; Douzgou, Sofia; Cooper, Nicola S; Tan, Ene-Choo; Foo, Roger; Lai, Angeline H M; Rankin, Julia; Green, Andrew; Lönnqvist, Tuula; Isohanni, Pirjo; Williams, Shelley; Ruhoy, Ilene; Carvalho, Karen S; Dowling, James J; Lev, Dorit L; Sterbova, Katalin; Lassuthova, Petra; Neupauerová, Jana; Waugh, Jeff L; Keros, Sotirios; Clayton-Smith, Jill; Smithson, Sarah F; Brunner, Han G; van Hoeckel, Ceciel; Anderson, Mel; Clowes, Virginia E; Siu, Victoria Mok; DDD study, The; Selber, Paulo; Leventer, Richard J; Nellaker, Christoffer; Niessing, Dierk; Hunt, David; Baralle, Diana

    2018-01-01

    Background De novo mutations in PURA have recently been described to cause PURA syndrome, a neurodevelopmental disorder characterised by severe intellectual disability (ID), epilepsy, feeding difficulties and neonatal hypotonia. Objectives To delineate the clinical spectrum of PURA syndrome and study genotype-phenotype correlations. Methods Diagnostic or research-based exome or Sanger sequencing was performed in individuals with ID. We systematically collected clinical and mutation data on newly ascertained PURA syndrome individuals, evaluated data of previously reported individuals and performed a computational analysis of photographs. We classified mutations based on predicted effect using 3D in silico models of crystal structures of Drosophila-derived Pur-alpha homologues. Finally, we explored genotype-phenotype correlations by analysis of both recurrent mutations as well as mutation classes. Results We report mutations in PURA (purine-rich element binding protein A) in 32 individuals, the largest cohort described so far. Evaluation of clinical data, including 22 previously published cases, revealed that all have moderate to severe ID and neonatal-onset symptoms, including hypotonia (96%), respiratory problems (57%), feeding difficulties (77%), exaggerated startle response (44%), hypersomnolence (66%) and hypothermia (35%). Epilepsy (54%) and gastrointestinal (69%), ophthalmological (51%) and endocrine problems (42%) were observed frequently. Computational analysis of facial photographs showed subtle facial dysmorphism. No strong genotype-phenotype correlation was identified by subgrouping mutations into functional classes. Conclusion We delineate the clinical spectrum of PURA syndrome with the identification of 32 additional individuals. The identification of one individual through targeted Sanger sequencing points towards the clinical recognisability of the syndrome. Genotype-phenotype analysis showed no significant correlation between mutation classes and

  9. ESTRO consensus guideline on target volume delineation for elective radiation therapy of early stage breast cancer

    International Nuclear Information System (INIS)

    Offersen, Birgitte V.; Boersma, Liesbeth J.; Kirkove, Carine; Hol, Sandra; Aznar, Marianne C.; Biete Sola, Albert; Kirova, Youlia M.; Pignol, Jean-Philippe; Remouchamps, Vincent; Verhoeven, Karolien; Weltens, Caroline; Arenas, Meritxell; Gabrys, Dorota; Kopek, Neil; Krause, Mechthild; Lundstedt, Dan; Marinko, Tanja

    2015-01-01

    Background and purpose: Delineation of clinical target volumes (CTVs) is a weak link in radiation therapy (RT), and large inter-observer variation is seen in breast cancer patients. Several guidelines have been proposed, but most result in larger CTVs than based on conventional simulator-based RT. The aim was to develop a delineation guideline obtained by consensus between a broad European group of radiation oncologists. Material and methods: During ESTRO teaching courses on breast cancer, teachers sought consensus on delineation of CTV through dialogue based on cases. One teacher delineated CTV on CT scans of 2 patients, followed by discussion and adaptation of the delineation. The consensus established between teachers was sent to other teams working in the same field, both locally and on a national level, for their input. This was followed by developing a broad consensus based on discussions. Results: Borders of the CTV encompassing a 5 mm margin around the large veins, running through the regional lymph node levels were agreed, and for the breast/thoracic wall other vessels were pointed out to guide delineation, with comments on margins for patients with advanced breast cancer. Conclusion: The ESTRO consensus on CTV for elective RT of breast cancer, endorsed by a broad base of the radiation oncology community, is presented to improve consistency

  10. High-order Path Integral Monte Carlo methods for solving strongly correlated fermion problems

    Science.gov (United States)

    Chin, Siu A.

    2015-03-01

    In solving for the ground state of a strongly correlated many-fermion system, the conventional second-order Path Integral Monte Carlo method is plagued with the sign problem. This is due to the large number of anti-symmetric free fermion propagators that are needed to extract the square of the ground state wave function at large imaginary time. In this work, I show that optimized fourth-order Path Integral Monte Carlo methods, which uses no more than 5 free-fermion propagators, in conjunction with the use of the Hamiltonian energy estimator, can yield accurate ground state energies for quantum dots with up to 20 polarized electrons. The correlations are directly built-in and no explicit wave functions are needed. This work is supported by the Qatar National Research Fund NPRP GRANT #5-674-1-114.

  11. Optimising delineation accuracy of tumours in PET for radiotherapy planning using blind deconvolution

    International Nuclear Information System (INIS)

    Guvenis, A.; Koc, A.

    2015-01-01

    Positron emission tomography (PET) imaging has been proven to be useful in radiotherapy planning for the determination of the metabolically active regions of tumours. Delineation of tumours, however, is a difficult task in part due to high noise levels and the partial volume effects originating mainly from the low camera resolution. The goal of this work is to study the effect of blind deconvolution on tumour volume estimation accuracy for different computer-aided contouring methods. The blind deconvolution estimates the point spread function (PSF) of the imaging system in an iterative manner in a way that the likelihood of the given image being the convolution output is maximised. In this way, the PSF of the imaging system does not need to be known. Data were obtained from a NEMA NU-2 IQ-based phantom with a GE DSTE-16 PET/CT scanner. The artificial tumour diameters were 13, 17, 22, 28 and 37 mm with a target/background ratio of 4:1. The tumours were delineated before and after blind deconvolution. Student's two-tailed paired t-test showed a significant decrease in volume estimation error ( p < 0.001) when blind deconvolution was used in conjunction with computer-aided delineation methods. A manual delineation confirmation demonstrated an improvement from 26 to 16 % for the artificial tumour of size 37 mm while an improvement from 57 to 15 % was noted for the small tumour of 13 mm. Therefore, it can be concluded that blind deconvolution of reconstructed PET images may be used to increase tumour delineation accuracy. (authors)

  12. Reduced-Order Direct Numerical Simulation of Solute Transport in Porous Media

    Science.gov (United States)

    Mehmani, Yashar; Tchelepi, Hamdi

    2017-11-01

    Pore-scale models are an important tool for analyzing fluid dynamics in porous materials (e.g., rocks, soils, fuel cells). Current direct numerical simulation (DNS) techniques, while very accurate, are computationally prohibitive for sample sizes that are statistically representative of the porous structure. Reduced-order approaches such as pore-network models (PNM) aim to approximate the pore-space geometry and physics to remedy this problem. Predictions from current techniques, however, have not always been successful. This work focuses on single-phase transport of a passive solute under advection-dominated regimes and delineates the minimum set of approximations that consistently produce accurate PNM predictions. Novel network extraction (discretization) and particle simulation techniques are developed and compared to high-fidelity DNS simulations for a wide range of micromodel heterogeneities and a single sphere pack. Moreover, common modeling assumptions in the literature are analyzed and shown that they can lead to first-order errors under advection-dominated regimes. This work has implications for optimizing material design and operations in manufactured (electrodes) and natural (rocks) porous media pertaining to energy systems. This work was supported by the Stanford University Petroleum Research Institute for Reservoir Simulation (SUPRI-B).

  13. Perioperative Clinical Nurse Specialist Role Delineation: A Systematic Review

    National Research Council Canada - National Science Library

    Cole, Lisa M; Walker, Theodore J; Nader, Kelly C; Glover, Dennis E; Newkirk, Laura E

    2006-01-01

    A clearly defined role of the Perioperative Clinical Nurse Specialist (PONS) is not identified. The purpose of this study was to provide recommendations for a delineated role of the PONS that will provide role clarity and practice guidance...

  14. Closed form solution to a second order boundary value problem and its application in fluid mechanics

    International Nuclear Information System (INIS)

    Eldabe, N.T.; Elghazy, E.M.; Ebaid, A.

    2007-01-01

    The Adomian decomposition method is used by many researchers to investigate several scientific models. In this Letter, the modified Adomian decomposition method is applied to construct a closed form solution for a second order boundary value problem with singularity

  15. SU-E-J-07: A Functional MR Protocol for the Pancreatic Tumor Delineation

    International Nuclear Information System (INIS)

    Andreychenko, A; Heerkens, H; Meijer, G; Vulpen, M van; Lagendijk, J; Berg, C van den

    2014-01-01

    Purpose: Pancreatic cancer is one of the cancers with the poorest survival prognosis. At the time of diagnosis most of pancreatic cancers are unresectable and those patients can be treated by radiotherapy. Radiotherapy for pancreatic cancer is limited due to uncertainties in CT-based delineations. MRI provides an excellent soft tissue contrast. Here, an MR protocol is developed to improve delineations for radiotherapy treatment of pancreatic cancer. In a later stage this protocol can also be used for on-line visualization of the pancreas during MRI guided treatments. Methods: Nine pancreatic cancer patients were included. The MR protocol included T2 weighted(T2w), T1 weighted(T1w), diffusion weighted(DWI) and dynamic contrast enhanced(DCE) techniques. The tumor was delineated on T2w and T1w MRI by an experienced radiation oncologist. Healthy pancreas or pancreatitis (assigned by the oncologist based on T2w) areas were also delineated. Apparent diffusion coefficient(ADC), and area under the curve(AUC)/time to peak(TTP) maps were obtained from DWI and DCE scans, respectively. Results: A clear demarcation of tumor area was visible on b800 DWI images in 5 patients. ADC maps of those patients characterized tumor as an area with restricted water diffusion. Tumor delineations based on solely DCE were possible in 7 patients. In 6 of those patients AUC maps demonstrated tumor heterogeneity: a hypointense area with a hyperintense ring. TTP values clearly discriminated the tumor and the healthy pancreas but could not distinguish tumor and the pancreatitis accurately. Conclusion: MR imaging results in a more pronounced tumor contrast than contrast enhanced CT. The addition of quantitative, functional MRI provides valuable, additional information to the radiation oncologist on the spatial tumor extent by discriminating tumor from the healthy pancreas(TTP, DWI) and characterizing the tumor(ADC). Our findings indicate that tumor delineation in pancreatic cancer can greatly

  16. SU-E-J-07: A Functional MR Protocol for the Pancreatic Tumor Delineation

    Energy Technology Data Exchange (ETDEWEB)

    Andreychenko, A; Heerkens, H; Meijer, G; Vulpen, M van; Lagendijk, J; Berg, C van den [UMC Utrecht, Utrecht, Utrecht (Netherlands)

    2014-06-01

    Purpose: Pancreatic cancer is one of the cancers with the poorest survival prognosis. At the time of diagnosis most of pancreatic cancers are unresectable and those patients can be treated by radiotherapy. Radiotherapy for pancreatic cancer is limited due to uncertainties in CT-based delineations. MRI provides an excellent soft tissue contrast. Here, an MR protocol is developed to improve delineations for radiotherapy treatment of pancreatic cancer. In a later stage this protocol can also be used for on-line visualization of the pancreas during MRI guided treatments. Methods: Nine pancreatic cancer patients were included. The MR protocol included T2 weighted(T2w), T1 weighted(T1w), diffusion weighted(DWI) and dynamic contrast enhanced(DCE) techniques. The tumor was delineated on T2w and T1w MRI by an experienced radiation oncologist. Healthy pancreas or pancreatitis (assigned by the oncologist based on T2w) areas were also delineated. Apparent diffusion coefficient(ADC), and area under the curve(AUC)/time to peak(TTP) maps were obtained from DWI and DCE scans, respectively. Results: A clear demarcation of tumor area was visible on b800 DWI images in 5 patients. ADC maps of those patients characterized tumor as an area with restricted water diffusion. Tumor delineations based on solely DCE were possible in 7 patients. In 6 of those patients AUC maps demonstrated tumor heterogeneity: a hypointense area with a hyperintense ring. TTP values clearly discriminated the tumor and the healthy pancreas but could not distinguish tumor and the pancreatitis accurately. Conclusion: MR imaging results in a more pronounced tumor contrast than contrast enhanced CT. The addition of quantitative, functional MRI provides valuable, additional information to the radiation oncologist on the spatial tumor extent by discriminating tumor from the healthy pancreas(TTP, DWI) and characterizing the tumor(ADC). Our findings indicate that tumor delineation in pancreatic cancer can greatly

  17. Using sequential indicator simulation to assess the uncertainty of delineating heavy-metal contaminated soils

    International Nuclear Information System (INIS)

    Juang, Kai-Wei; Chen, Yue-Shin; Lee, Dar-Yuan

    2004-01-01

    Mapping the spatial distribution of soil pollutants is essential for delineating contaminated areas. Currently, geostatistical interpolation, kriging, is increasingly used to estimate pollutant concentrations in soils. The kriging-based approach, indicator kriging (IK), may be used to model the uncertainty of mapping. However, a smoothing effect is usually produced when using kriging in pollutant mapping. The detailed spatial patterns of pollutants could, therefore, be lost. The local uncertainty of mapping pollutants derived by the IK technique is referred to as the conditional cumulative distribution function (ccdf) for one specific location (i.e. single-location uncertainty). The local uncertainty information obtained by IK is not sufficient as the uncertainty of mapping at several locations simultaneously (i.e. multi-location uncertainty or spatial uncertainty) is required to assess the reliability of the delineation of contaminated areas. The simulation approach, sequential indicator simulation (SIS), which has the ability to model not only single, but also multi-location uncertainties, was used, in this study, to assess the uncertainty of the delineation of heavy metal contaminated soils. To illustrate this, a data set of Cu concentrations in soil from Taiwan was used. The results show that contour maps of Cu concentrations generated by the SIS realizations exhausted all the spatial patterns of Cu concentrations without the smoothing effect found when using the kriging method. Based on the SIS realizations, the local uncertainty of Cu concentrations at a specific location of x', refers to the probability of the Cu concentration z(x') being higher than the defined threshold level of contamination (z c ). This can be written as Prob SIS [z(x')>z c ], representing the probability of contamination. The probability map of Prob SIS [z(x')>z c ] can then be used for delineating contaminated areas. In addition, the multi-location uncertainty of an area A,delineated

  18. 1:100,000 Papermap Quadrangle Index of Louisiana, Geographic NAD83, USGS (1999) [quad100K_papermaps_USGS_1999

    Data.gov (United States)

    Louisiana Geographic Information Center — This is a double precision polygon dataset delineating the geographic footprint of the 100k series map sheets published by the USGS. Because most of these map sheets...

  19. Algorithms and ordering heuristics for distributed constraint satisfaction problems

    CERN Document Server

    Wahbi , Mohamed

    2013-01-01

    DisCSP (Distributed Constraint Satisfaction Problem) is a general framework for solving distributed problems arising in Distributed Artificial Intelligence.A wide variety of problems in artificial intelligence are solved using the constraint satisfaction problem paradigm. However, there are several applications in multi-agent coordination that are of a distributed nature. In this type of application, the knowledge about the problem, that is, variables and constraints, may be logically or geographically distributed among physical distributed agents. This distribution is mainly due to p

  20. 78 FR 23969 - Ewan 1, INC. n/k/a AccessKey IP, Inc.; Order of Suspension of Trading

    Science.gov (United States)

    2013-04-23

    ... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] Ewan 1, INC. n/k/a AccessKey IP, Inc.; Order of Suspension of Trading April 19, 2013. It appears to the Securities and Exchange Commission that... AccessKey IP, Inc. (``AccessKey'') because it has not filed a periodic report since it filed its...

  1. In situ removal of carbon contamination from a chromium-coated mirror: ideal optics to suppress higher-order harmonics in the carbon K-edge region.

    Science.gov (United States)

    Toyoshima, Akio; Kikuchi, Takashi; Tanaka, Hirokazu; Mase, Kazuhiko; Amemiya, Kenta

    2015-11-01

    Carbon-free chromium-coated optics are ideal in the carbon K-edge region (280-330 eV) because the reflectivity of first-order light is larger than that of gold-coated optics while the second-order harmonics (560-660 eV) are significantly suppressed by chromium L-edge and oxygen K-edge absorption. Here, chromium-, gold- and nickel-coated mirrors have been adopted in the vacuum ultraviolet and soft X-ray branch beamline BL-13B at the Photon Factory in Tsukuba, Japan. Carbon contamination on the chromium-coated mirror was almost completely removed by exposure to oxygen at a pressure of 8 × 10(-2) Pa for 1 h under irradiation of non-monochromated synchrotron radiation. The pressure in the chamber recovered to the order of 10(-7) Pa within a few hours. The reflectivity of the chromium-coated mirror of the second-order harmonics in the carbon K-edge region (560-660 eV) was found to be a factor of 0.1-0.48 smaller than that of the gold-coated mirror.

  2. EXISTENCE OF POSITIVE SOLUTION TO TWO-POINT BOUNDARY VALUE PROBLEM FOR A SYSTEM OF SECOND ORDER ORDINARY DIFFERENTIAL EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, we consider a two-point boundary value problem for a system of second order ordinary differential equations. Under some conditions, we show the existence of positive solution to the system of second order ordinary differential equa-tions.

  3. Applications of ordered weighted averaging (OWA operators in environmental problems

    Directory of Open Access Journals (Sweden)

    Carlos Llopis-Albert

    2017-04-01

    Full Text Available This paper presents an application of a prioritized weighted aggregation operator based on ordered weighted averaging (OWA to deal with stakeholders' constructive participation in water resources projects. They have different degree of acceptance or preference regarding the measures and policies to be carried out, which lead to different environmental and socio-economic outcomes, and hence, to different levels of stakeholders’ satisfaction. The methodology establishes a prioritization relationship upon the stakeholders, which preferences are aggregated by means of weights depending on the satisfaction of the higher priority policy maker. The methodology establishes a prioritization relationship upon the stakeholders, which preferences are aggregated by means of weights depending on the satisfaction of the higher priority policy maker. The methodology has been successfully applied to a Public Participation Project (PPP in watershed management, thus obtaining efficient environmental measures in conflict resolution problems under actors’ preference uncertainties.

  4. The Y2K problem; assessment of the safety of nuclear facilities by IPSN (France)

    International Nuclear Information System (INIS)

    Henry, J.Y.

    1999-01-01

    The millennium bug (or Y2K problem) could lead to a common cause failure of the Nuclear Power Plant computer based systems. This report discusses Y2K related issues with respect to the safety of the nuclear power plants. The consequences of failures must be estimated to assess the impact on the safety of the installation, taking into account that these installations were designed with due allowance for the possibility of failure of equipment or components. The main objective of the work done by operators and licensees is aimed at ensuring the millennium bug could not cause failure or unavailability of equipment or components which are needed for the safety of the installation. The obvious solution is to correct the sensitive systems so that the potential failures could not occur. Moreover, the risk of a loss of grid should be taken into account as the safety of nuclear power plants depends upon plant resources and consequently the delay necessary to recover external electrical sources. Safety authority (DSIN) has issued recommendations asking for reporting periodically the progress and results of the Y2K plan the licensees and operators have to implement for Y2K readiness. The analysis done by IPSN the technical support of the safety authority, is presented as the majority of the Y2K related activities have been done by the licensee (EDF). Up to now, France is on the tracks. If some works are still ahead, the results shown today are rather reflecting the readiness of the nuclear installations in due time. (author)

  5. Early prediction of lung cancer recurrence after stereotactic radiotherapy using second order texture statistics

    Science.gov (United States)

    Mattonen, Sarah A.; Palma, David A.; Haasbeek, Cornelis J. A.; Senan, Suresh; Ward, Aaron D.

    2014-03-01

    Benign radiation-induced lung injury is a common finding following stereotactic ablative radiotherapy (SABR) for lung cancer, and is often difficult to differentiate from a recurring tumour due to the ablative doses and highly conformal treatment with SABR. Current approaches to treatment response assessment have shown limited ability to predict recurrence within 6 months of treatment. The purpose of our study was to evaluate the accuracy of second order texture statistics for prediction of eventual recurrence based on computed tomography (CT) images acquired within 6 months of treatment, and compare with the performance of first order appearance and lesion size measures. Consolidative and ground-glass opacity (GGO) regions were manually delineated on post-SABR CT images. Automatic consolidation expansion was also investigated to act as a surrogate for GGO position. The top features for prediction of recurrence were all texture features within the GGO and included energy, entropy, correlation, inertia, and first order texture (standard deviation of density). These predicted recurrence with 2-fold cross validation (CV) accuracies of 70-77% at 2- 5 months post-SABR, with energy, entropy, and first order texture having leave-one-out CV accuracies greater than 80%. Our results also suggest that automatic expansion of the consolidation region could eliminate the need for manual delineation, and produced reproducible results when compared to manually delineated GGO. If validated on a larger data set, this could lead to a clinically useful computer-aided diagnosis system for prediction of recurrence within 6 months of SABR and allow for early salvage therapy for patients with recurrence.

  6. Strongly coupled single-phase flow problems: Effects of density variation, hydrodynamic dispersion, and first order decay

    Energy Technology Data Exchange (ETDEWEB)

    Oldenburg, C.M.; Pruess, K. [Lawrence Berkeley Laboratory, Berkeley, CA (United States)

    1995-03-01

    We have developed TOUGH2 modules for strongly coupled flow and transport that include full hydrodynamic dispersion. T2DM models tow-dimensional flow and transport in systems with variable salinity, while T32DMR includes radionuclide transport with first-order decay of a parent-daughter chain of radionuclide components in variable salinity systems. T2DM has been applied to a variety of coupled flow problems including the pure solutal convection problem of Elder and the mixed free and forced convection salt-dome flow problem. In the Elder and salt-dome flow problems, density changes of up to 20% caused by brine concentration variations lead to strong coupling between the velocity and brine concentration fields. T2DM efficiently calculates flow and transport for these problems. We have applied T2DMR to the dispersive transport and decay of radionuclide tracers in flow fields with permeability heterogeneities and recirculating flows. Coupling in these problems occurs by velocity-dependent hydrodynamic dispersion. Our results show that the maximum daughter species concentration may occur fully within a recirculating or low-velocity region. In all of the problems, we observe very efficient handling of the strongly coupled flow and transport processes.

  7. A New Method Based On Modified Shuffled Frog Leaping Algorithm In Order To Solve Nonlinear Large Scale Problem

    Directory of Open Access Journals (Sweden)

    Aliasghar Baziar

    2015-03-01

    Full Text Available Abstract In order to handle large scale problems this study has used shuffled frog leaping algorithm. This algorithm is an optimization method based on natural memetics that uses a new two-phase modification to it to have a better search in the problem space. The suggested algorithm is evaluated by comparing to some well known algorithms using several benchmark optimization problems. The simulation results have clearly shown the superiority of this algorithm over other well-known methods in the area.

  8. Gaming disorder: Its delineation as an important condition for diagnosis, management, and prevention.

    Science.gov (United States)

    Saunders, John B; Hao, Wei; Long, Jiang; King, Daniel L; Mann, Karl; Fauth-Bühler, Mira; Rumpf, Hans-Jürgen; Bowden-Jones, Henrietta; Rahimi-Movaghar, Afarin; Chung, Thomas; Chan, Elda; Bahar, Norharlina; Achab, Sophia; Lee, Hae Kook; Potenza, Marc; Petry, Nancy; Spritzer, Daniel; Ambekar, Atul; Derevensky, Jeffrey; Griffiths, Mark D; Pontes, Halley M; Kuss, Daria; Higuchi, Susumu; Mihara, Satoko; Assangangkornchai, Sawitri; Sharma, Manoj; Kashef, Ahmad El; Ip, Patrick; Farrell, Michael; Scafato, Emanuele; Carragher, Natacha; Poznyak, Vladimir

    2017-09-01

    Online gaming has greatly increased in popularity in recent years, and with this has come a multiplicity of problems due to excessive involvement in gaming. Gaming disorder, both online and offline, has been defined for the first time in the draft of 11th revision of the International Classification of Diseases (ICD-11). National surveys have shown prevalence rates of gaming disorder/addiction of 10%-15% among young people in several Asian countries and of 1%-10% in their counterparts in some Western countries. Several diseases related to excessive gaming are now recognized, and clinics are being established to respond to individual, family, and community concerns, but many cases remain hidden. Gaming disorder shares many features with addictions due to psychoactive substances and with gambling disorder, and functional neuroimaging shows that similar areas of the brain are activated. Governments and health agencies worldwide are seeking for the effects of online gaming to be addressed, and for preventive approaches to be developed. Central to this effort is a need to delineate the nature of the problem, which is the purpose of the definitions in the draft of ICD-11.

  9. Delineating wetland catchments and modeling hydrologic connectivity using lidar data and aerial imagery

    Directory of Open Access Journals (Sweden)

    Q. Wu

    2017-07-01

    Full Text Available In traditional watershed delineation and topographic modeling, surface depressions are generally treated as spurious features and simply removed from a digital elevation model (DEM to enforce flow continuity of water across the topographic surface to the watershed outlets. In reality, however, many depressions in the DEM are actual wetland landscape features with seasonal to permanent inundation patterning characterized by nested hierarchical structures and dynamic filling–spilling–merging surface-water hydrological processes. Differentiating and appropriately processing such ecohydrologically meaningful features remains a major technical terrain-processing challenge, particularly as high-resolution spatial data are increasingly used to support modeling and geographic analysis needs. The objectives of this study were to delineate hierarchical wetland catchments and model their hydrologic connectivity using high-resolution lidar data and aerial imagery. The graph-theory-based contour tree method was used to delineate the hierarchical wetland catchments and characterize their geometric and topological properties. Potential hydrologic connectivity between wetlands and streams were simulated using the least-cost-path algorithm. The resulting flow network delineated potential flow paths connecting wetland depressions to each other or to the river network on scales finer than those available through the National Hydrography Dataset. The results demonstrated that our proposed framework is promising for improving overland flow simulation and hydrologic connectivity analysis.

  10. 1:24,000 Papermap Quadrangle Index of Louisiana, Geographic NAD83, USGS (1999) [quad24K_papermaps_USGS_1999

    Data.gov (United States)

    Louisiana Geographic Information Center — This is a polygon dataset delineating the geographic footprint of the 24k (7.5') series map sheets published by the USGS. Because most of these map sheets have also...

  11. Maritime zones delimitation - Problems and solutions

    Science.gov (United States)

    Kastrisios, Christos; Tsoulos, Lysandros

    2018-05-01

    The delimitation of maritime zones and boundaries foreseen by the United Nations Convention on the Law of the Sea (UNCLOS) is a factor of economic growth, effective management of the coastal and ocean environment and the cornerstone for maritime spatial planning. Maritime zones and boundaries form the outermost limits of coastal states and their accurate delineation and cartographic portrayal is a matter of national priority. Although UNCLOS is a legal document, its implementation -at first place- is purely technical and requires -amongst others- theoretical and applied background on Geodesy, Cartography and Geographic Information Systems (GIS) for those involved. This paper provides a brief historical background of the evolution of the UNCLOS, presents the various concepts of the Convention and identifies the problems inherent in the maritime delimitation process. Furthermore, it presents solutions that will facilitate the cartographer's work in order to achieve unquestionable results. Through the paper it becomes evident that the role of the cartographer and the GIS expert is critical for the successful implementation of maritime delimitation.

  12. Explicit higher order symplectic integrator for s-dependent magnetic field

    International Nuclear Information System (INIS)

    Wu, Y.; Forest, E.; Robin, D.S.

    2001-01-01

    We derive second and higher order explicit symplectic integrators for the charged particle motion in an s-dependent magnetic field with the paraxial approximation. The Hamiltonian of such a system takes the form of H (summation) k (p k - a k (rvec q), s) 2 + V((rvec q), s). This work solves a long-standing problem for modeling s-dependent magnetic elements. Important applications of this work include the studies of the charged particle dynamics in a storage ring with strong field wigglers, arbitrarily polarized insertion devices,and super-conducting magnets with strong fringe fields. Consequently, this work will have a significant impact on the optimal use of the above magnetic devices in the light source rings as well as in next generation linear collider damping rings

  13. Incommensurate antiferromagnetic order in the manifoldly-frustrated SrTb2O4 with transition temperature up to 4.28 K

    Directory of Open Access Journals (Sweden)

    Haifeng eLi

    2014-07-01

    Full Text Available The Neel temperature of the new frustrated family of SrRE2O4 (RE = rare earth compounds is yet limited to 0.9 K, which more or less hampers a complete understanding of the magnetic frustrations and spin interactions. Here we report on a new frustrated member to the family, SrTb2O4 with a record TN = 4.28(2 K, and an experimental study of the magnetic interacting and frustrating mechanisms by polarized and unpolarized neutron scattering. The compound of SrTb2O4 displays an incommensurate antiferromagnetic (AFM order with a transverse wave vector Q = (0.5924(1, 0.0059(1, 0 albeit with partially-ordered moments, 1.92(6 uB at 0.5 K, stemming from only one of the two inequivalent Tb sites by virtue of their different octahedral distortions. The localized moments are confined to the bc plane, 11.9(66 degree away from the b axis by single-ion anisotropy. We reveal that this AFM order is dominated mainly by dipole-dipole interactions and disclose that the octahedral distortion, nearest-neighbour (NN ferromagnetic (FM arrangement, different next NN FM and AFM configurations, and in-plane anisotropic spin correlations are vital to the magnetic structure and associated multiple frustrations. The discovery of the thus far highest AFM transition temperature renders SrTb2O4 a new friendly frustrated platform in the family for exploring the nature of magnetic interactions and frustrations.

  14. Objective and subjective image quality of primary and recurrent squamous cell carcinoma on head and neck low-tube-voltage 80-kVp computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Scholtz, Jan-Erik; Kaup, Moritz; Kraft, Johannes; Noeske, Eva-Maria; Schulz, Boris; Burck, Iris; Kerl, J.M.; Bauer, Ralf W.; Lehnert, Thomas; Vogl, Thomas J.; Wichmann, Julian L. [University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Scheerer, Friedrich [University Hospital Frankfurt, Department of Cranio-Maxillofacial and Plastic Facial Surgery, Frankfurt (Germany); Wagenblast, Jens [University Hospital Frankfurt, Department of Otolaryngology, Head and Neck Surgery, Frankfurt (Germany)

    2015-03-26

    To investigate low-tube-voltage 80-kVp computed tomography (CT) of head and neck primary and recurrent squamous cell carcinoma (SCC) regarding objective and subjective image quality. We retrospectively evaluated 65 patients (47 male, 18 female; mean age: 62.1 years) who underwent head and neck dual-energy CT (DECT) due to biopsy-proven primary (n = 50) or recurrent (n = 15) SCC. Eighty peak kilovoltage and standard blended 120-kVp images were compared. Attenuation and noise of malignancy and various soft tissue structures were measured. Tumor signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Subjective image quality was rated by three reviewers using 5-point grading scales regarding overall image quality, lesion delineation, image sharpness, and image noise. Radiation dose was assessed as CT dose index volume (CTDI{sub vol}). Interobserver agreement was calculated using intraclass correlation coefficient (ICC). Mean tumor attenuation (153.8 Hounsfield unit (HU) vs. 97.1 HU), SNR (10.7 vs. 8.3), CNR (8.1 vs. 4.8), and subjective tumor delineation (score, 4.46 vs. 4.13) were significantly increased (all P < 0.001) with 80-kVp acquisition compared to standard blended 120-kVp images. Noise of all measured structures was increased in 80-kVp acquisition (P < 0.001). Overall interobserver agreement was good (ICC, 0.86; 95 % confidence intervals: 0.82-0.89). CTDI{sub vol} was reduced by 48.7 % with 80-kVp acquisition compared to standard DECT (4.85 ± 0.51 vs. 9.94 ± 0.81 mGy cm, P < 0.001). Head and neck CT with low-tube-voltage 80-kVp acquisition provides increased tumor delineation, SNR, and CNR for CT imaging of primary and recurrent SCC compared to standard 120-kVp acquisition with an accompanying significant reduction of radiation exposure. (orig.)

  15. Online Appendix to Y2K

    OpenAIRE

    Stephanie Schmitt-Grohe; Martin Uribe

    1998-01-01

    As the millenium draws to an end, the threat posed by the Year 2000 (Y2K) problem is inducing vast private and public spending on its remediation. In this paper, we embed the Y2K problem into a dynamic general equilibrium framework. We model the Y2K problem as an anticipated, permanent loss to output whose magnitude can be lessened by investing resources in advance. Our model replicates three observed characteristics of the dynamics triggered by the Y2K bug: (1) Precautionary investment: inve...

  16. Target volume delineation for head and neck cancer intensity-modulated radiotherapy; Delineation des volumes cibles des cancers des voies aerodigestives superieures en radiotherapie conformationnelle avec modulation d'intensite

    Energy Technology Data Exchange (ETDEWEB)

    Lapeyre, M.; Toledano, I.; Bourry, N. [Departement de radiotherapie, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1 (France); Bailly, C. [Unite de radiodiagnostic, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1 (France); Cachin, F. [Unite de medecine nucleaire, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1 (France)

    2011-10-15

    This article describes the determination and the delineation of the target volumes for head-and-neck cancers treated with intensity-modulated radiotherapy (IMRT). The delineation of the clinical target volumes (CTV) on the computerized tomography scanner (CT scan) requires a rigorous methodology due to the complexity of head-and-neck anatomy. The clinical examination with a sketch of pretreatment tumour extension, the surgical and pathological reports and the adequate images (CT scan, magnetic resonance imaging and fluorodeoxyglucose positron emission tomography) are necessary for the delineation. The target volumes depend on the overall strategy: sequential IMRT or simultaneous integrated boost-IMRT (SIB-IMRT). The concept of selectivity of the potential subclinical disease near the primary tumor and the selection of neck nodal targets are described according to the recommendations and the literature. The planing target volume (PTV), mainly reflecting setup errors (random and systematic), results from a uniform 4-5 mm expansion around the CTV. We propose the successive delineation of: (1) the gross volume tumour (GTV); (2) the 'high risk' CTV1 around the GTV or including the postoperative tumour bed in case of positive margins or nodal extra-capsular spread (65-70 Gy in 30-35 fractions); (3) the CTV2 'intermediate risk' around the CTV1 for SIB-IMRT (59-63 Gy in 30-35 fractions); (4) the 'low-risk' CTV3 (54-56 Gy in 30-35 fractions); (5) the PTVs. (authors)

  17. Layer potentials and boundary-value problems for second order elliptic operators with data in Besov spaces

    CERN Document Server

    Barton, Ariel

    2016-01-01

    This monograph presents a comprehensive treatment of second order divergence form elliptic operators with bounded measurable t-independent coefficients in spaces of fractional smoothness, in Besov and weighted L^p classes. The authors establish: (1) Mapping properties for the double and single layer potentials, as well as the Newton potential; (2) Extrapolation-type solvability results: the fact that solvability of the Dirichlet or Neumann boundary value problem at any given L^p space automatically assures their solvability in an extended range of Besov spaces; (3) Well-posedness for the non-homogeneous boundary value problems. In particular, the authors prove well-posedness of the non-homogeneous Dirichlet problem with data in Besov spaces for operators with real, not necessarily symmetric, coefficients.

  18. Analiticity in fourth-order wave equations

    International Nuclear Information System (INIS)

    Bollini, C.G.; Giambiagi, J.J.

    1987-01-01

    In this paper it is presented, through a familiar example (δ-function potential in one dimension), the analytic properties of Jost functions associated with fourth-order equations. It is shown how to construct the Jost functions and the two discontinuity matrices associated with the line of singularities. The latter divide the complex k-plane in eight regions of analiticity. One of these matrices is related to the asymptotic behaviour of the scattering state. The other is not. Both are necessary to solve the inverse problem. Besides the usual poles related to bound states there are also other poles associated with total reflexion

  19. Analiticity in fourth order wave equations

    International Nuclear Information System (INIS)

    Bollini, C.G.

    1987-01-01

    Through a familiar example (δ-function potential in one dimension) the analytic properties of Jost functions associated with fourth order equations are presented. It is shown how to construct the Jost functions and the two discontinuities matrices associated to the line of singularities. The latter divide the complex k-plane in eight regions of analiticity. One of these matrices is related to the asymptotic behaviour of scattering state. The other is not. Both being necessary to solve the inverse problem. Besides the usual poles related to bound states there are also other poles associated with total reflexion. (Author) [pt

  20. A multilevel cost-space approach to solving the balanced long transportation problem

    Science.gov (United States)

    Cavanaugh, Kevin J.; Henson, Van Emden

    1993-01-01

    We develop a multilevel scheme for solving the balanced long transportation problem, that is, given a set (c(sub kj)) of shipping costs from a set of M supply nodes S(sub k) to a set of N demand nodes D(sub j), we seek to find a set of flows, (x(sub kj)), that minimizes the total cost Sigma(sub k=1)(exp M) Sigma(sub j=1)(exp N) x(sub kj)c(sub kj). We require that the problem be balanced, that is, the total demand must equal the total supply. Solution techniques for this problem are well known from optimization and linear programming. We examine this problem, however, in order to develop principles that can then be applied to more intractible problems of optimization. We develop a multigrid scheme for solving the problem, defining the grids, relaxation, and intergrid operators. Numerical experimentation shows that this line of research may prove fruitful. Further research directions are suggested.

  1. Application of Geophysical Techniques for 3D Geohazard Mapping to Delineate Cavities and Potential Sinkholes in the Northern Part of Kuala Lumpur, Malaysia

    Directory of Open Access Journals (Sweden)

    Zeinab Bakhshipour

    2013-01-01

    Full Text Available This work describes the application of the electrical resistivity (ER method to delineating subsurface structures and cavities in Kuala Lumpur Limestone within the Batu Cave area of Selangor Darul Ehsan, Malaysia. In all, 17 ER profiles were measured by using a Wenner electrode configuration with 2 m spacing. The field survey was accompanied by laboratory work, which involves taking resistivity measurements of rock, soil, and water samples taken from the field to obtain the formation factor. The relationship between resistivity and the formation factor and porosity for all the samples was established. The porosity values were plotted and contoured. A 2-dimensional and 3-dimensional representation of the subsurface topography of the area was prepared through use of commercial computer software. The results show the presence of cavities and sinkholes in some parts of the study area. This work could help engineers and environmental managers by providing the information necessary to produce a sustainable management plan in order to prevent catastrophic collapses of structures and other related geohazard problems.

  2. Remote sensing application for delineating coastal vegetation - A case study

    Digital Repository Service at National Institute of Oceanography (India)

    Kunte, P.D.; Wagle, B.G.

    Remote sensing data has been used for mapping coastal vegetation along the Goa Coast, India. The study envisages the use of digital image processing techniques for delineating geomorphic features and associated vegetation, including mangrove, along...

  3. Delineating Biophysical Environments of the Sunda Banda Seascape, Indonesia

    Directory of Open Access Journals (Sweden)

    Mingshu Wang

    2015-01-01

    Full Text Available The Sunda Banda Seascape (SBS, located in the center of the Coral Triangle, is a global center of marine biodiversity and a conservation priority. We proposed the first biophysical environmental delineation of the SBS using globally available satellite remote sensing and model-assimilated data to categorize this area into unique and meaningful biophysical classes. Specifically, the SBS was partitioned into eight biophysical classes characterized by similar sea surface temperature, chlorophyll a concentration, currents, and salinity patterns. Areas within each class were expected to have similar habitat types and ecosystem functions. Our work supplemented prevailing global marine management schemes by focusing in on a regional scale with finer spatial resolution. It also provided a baseline for academic research, ecological assessments and will facilitate marine spatial planning and conservation activities in the area. In addition, the framework and methods of delineating biophysical environments we presented can be expanded throughout the whole Coral Triangle to support research and conservation activities in this important region.

  4. Delineating Individual Trees from Lidar Data: A Comparison of Vector- and Raster-based Segmentation Approaches

    Directory of Open Access Journals (Sweden)

    Maggi Kelly

    2013-08-01

    Full Text Available Light detection and ranging (lidar data is increasingly being used for ecosystem monitoring across geographic scales. This work concentrates on delineating individual trees in topographically-complex, mixed conifer forest across the California’s Sierra Nevada. We delineated individual trees using vector data and a 3D lidar point cloud segmentation algorithm, and using raster data with an object-based image analysis (OBIA of a canopy height model (CHM. The two approaches are compared to each other and to ground reference data. We used high density (9 pulses/m2, discreet lidar data and WorldView-2 imagery to delineate individual trees, and to classify them by species or species types. We also identified a new method to correct artifacts in a high-resolution CHM. Our main focus was to determine the difference between the two types of approaches and to identify the one that produces more realistic results. We compared the delineations via tree detection, tree heights, and the shape of the generated polygons. The tree height agreement was high between the two approaches and the ground data (r2: 0.93–0.96. Tree detection rates increased for more dominant trees (8–100 percent. The two approaches delineated tree boundaries that differed in shape: the lidar-approach produced fewer, more complex, and larger polygons that more closely resembled real forest structure.

  5. K Basins Spent Nuclear Fuel (SNF) Project Safety Analysis Report for Packaging (SARP) approval plan

    International Nuclear Information System (INIS)

    1995-01-01

    This document delineates the plan for preparation, review, and approval of the K Basins Spent Nuclear Fuel (SNF) Packaging Design Criteria (PDC) document and the on-site Safety Analysis Report for Packaging (SARP). The packaging addressed in these documents is used to transport SNF in a Multi- canister Overpack (MCO) configuration

  6. Magnetic ordering in TmGa

    DEFF Research Database (Denmark)

    Cadogan, J.M.; Stewart, G.A.; Muños Pérez, S.

    2014-01-01

    We have determined the magnetic structure of the intermetallic compound TmGa by high-resolution neutron powder diffraction and 169Tm Mössbauer spectroscopy. This compound crystallizes in the orthorhombic (Cmcm) CrB-type structure and its magnetic structure is characterized by magnetic order...... of the Tm sublattice along the a-axis. The initial magnetic ordering occurs at 15(1) K and yields an incommensurate antiferromagnetic structure described by the propagation vector k1 = [0 0.275(2) 0]. At 12 K the dominant ferromagnetic ordering of the Tm sublattice along the a-axis develops in what appears...... to be a first-order transition. At 3 K the magnetic structure of TmGa is predominantly ferromagnetic but a weakened incommensurate component remains. The ferromagnetic Tm moment reaches 6.7(2) μB at 3 K and the amplitude of the remaining incommensurate component is 2.7(4) μB. The 169Tm hyperfine magnetic field...

  7. Recovery of point defects, created by neutron irradiation at 20 K, in ordered and disordered FeCo and FeCo2V alloys

    International Nuclear Information System (INIS)

    Dinhut, J.F.; Riviere, J.P.

    1978-01-01

    Samples of FeCo and FeCo2V ordered and disordered alloys were irradiated by fission neutrons at liquid hydrogen temperature up to an integrated dose of 7 x 10 17 n/cm 2 (E > 1 MeV), and then annealed. During the two first important recovery stages below 200 K, the annealing of about 60% of the radiation induced resistivity occurs. These two steps are respectively assigned to close pair recombination and rearrangement and detrapping of interstitials. During the annealing of the two other stages observed above 200 K, the migration and elimination of interstitials and vacancies involves ordering phenomena. These results and their interpretations are discussed in relation to those of pure metals and to those previously found in ordered and disordered alloys of the same type. (author)

  8. Sufficient condition for existence of solutions for higher-order resonance boundary value problem with one-dimensional p-Laplacian

    Directory of Open Access Journals (Sweden)

    Liu Yang

    2007-10-01

    Full Text Available By using coincidence degree theory of Mawhin, existence results for some higher order resonance multipoint boundary value problems with one dimensional p-Laplacian operator are obtained.

  9. How large is the Upper Indus Basin? The pitfalls of auto-delineation using DEMs

    Science.gov (United States)

    Khan, Asif; Richards, Keith S.; Parker, Geoffrey T.; McRobie, Allan; Mukhopadhyay, Biswajit

    2014-02-01

    Extraction of watershed areas from Digital Elevation Models (DEMs) is increasingly required in a variety of environmental analyses. It is facilitated by the availability of DEMs based on remotely sensed data, and by Geographical Information System (GIS) software. However, accurate delineation depends on the quality of the DEM and the methodology adopted. This paper considers automated and supervised delineation in a case study of the Upper Indus Basin (UIB), Pakistan, for which published estimates of the basin area show significant disagreement, ranging from 166,000 to 266,000 km2. Automated delineation used ArcGIS Archydro and hydrology tools applied to three good quality DEMs (two from SRTM data with 90m resolution, and one from 30m resolution ASTER data). Automatic delineation defined a basin area of c.440,000 km2 for the UIB, but included a large area of internal drainage in the western Tibetan Plateau. It is shown that discrepancies between different estimates reflect differences in the initial extent of the DEM used for watershed delineation, and the unchecked effect of iterative pit-filling of the DEM (going beyond the filling of erroneous pixels to filling entire closed basins). For the UIB we have identified critical points where spurious addition of catchment area has arisen, and use Google Earth to examine the geomorphology adjacent to these points, and also examine the basin boundary data provided by the HydroSHEDS database. We show that the Pangong Tso watershed and some other areas in the western Tibetan plateau are not part of the UIB, but are areas of internal drainage. Our best estimate of the area of the Upper Indus Basin (at Besham Qila) is 164,867 km2 based on the SRTM DEM, and 164,853 km2 using the ASTER DEM). This matches the catchment area measured by WAPDA SWHP. An important lesson from this investigation is that one should not rely on automated delineation, as iterative pit-filling can produce spurious drainage networks and basins, when

  10. A high-order integral solver for scalar problems of diffraction by screens and apertures in three-dimensional space

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Oscar P., E-mail: obruno@caltech.edu; Lintner, Stéphane K.

    2013-11-01

    We present a novel methodology for the numerical solution of problems of diffraction by infinitely thin screens in three-dimensional space. Our approach relies on new integral formulations as well as associated high-order quadrature rules. The new integral formulations involve weighted versions of the classical integral operators related to the thin-screen Dirichlet and Neumann problems as well as a generalization to the open-surface problem of the classical Calderón formulae. The high-order quadrature rules we introduce for these operators, in turn, resolve the multiple Green function and edge singularities (which occur at arbitrarily close distances from each other, and which include weakly singular as well as hypersingular kernels) and thus give rise to super-algebraically fast convergence as the discretization sizes are increased. When used in conjunction with Krylov-subspace linear algebra solvers such as GMRES, the resulting solvers produce results of high accuracy in small numbers of iterations for low and high frequencies alike. We demonstrate our methodology with a variety of numerical results for screen and aperture problems at high frequencies—including simulation of classical experiments such as the diffraction by a circular disc (featuring in particular the famous Poisson spot), evaluation of interference fringes resulting from diffraction across two nearby circular apertures, as well as solution of problems of scattering by more complex geometries consisting of multiple scatterers and cavities.

  11. subsurface sequence delineation and saline water mapping of lagos

    African Journals Online (AJOL)

    A subsurface sequence delineation and saline water mapping of Lagos State was carried out. Ten (10) deep boreholes with average depth of 300 m were drilled within the sedimentary basin. The boreholes were lithologically and geophysically logged. The driller's lithological logs aided by gamma and resistivity logs, ...

  12. Difference method for solving a nonlocal boundary value problem for a degenerating third-order pseudo-parabolic equation with variable coefficients

    Science.gov (United States)

    Beshtokov, M. Kh.

    2016-10-01

    A nonlocal boundary value problem for a degenerating third-order pseudo-parabolic equation with variable coefficients is considered. For solving this problem, a priori estimates in the differential and difference forms are obtained. The a priori estimates imply the uniqueness and stability of the solution on a layer with respect to the initial data and the right-hand side and the convergence of the solution of the difference problem to the solution of the differential problem.

  13. PET functional volume delineation: a robustness and repeatability study

    International Nuclear Information System (INIS)

    Hatt, Mathieu; Cheze-le Rest, Catherine; Albarghach, Nidal; Pradier, Olivier; Visvikis, Dimitris

    2011-01-01

    Current state-of-the-art algorithms for functional uptake volume segmentation in PET imaging consist of threshold-based approaches, whose parameters often require specific optimization for a given scanner and associated reconstruction algorithms. Different advanced image segmentation approaches previously proposed and extensively validated, such as among others fuzzy C-means (FCM) clustering, or fuzzy locally adaptive bayesian (FLAB) algorithm have the potential to improve the robustness of functional uptake volume measurements. The objective of this study was to investigate robustness and repeatability with respect to various scanner models, reconstruction algorithms and acquisition conditions. Robustness was evaluated using a series of IEC phantom acquisitions carried out on different PET/CT scanners (Philips Gemini and Gemini Time-of-Flight, Siemens Biograph and GE Discovery LS) with their associated reconstruction algorithms (RAMLA, TF MLEM, OSEM). A range of acquisition parameters (contrast, duration) and reconstruction parameters (voxel size) were considered for each scanner model, and the repeatability of each method was evaluated on simulated and clinical tumours and compared to manual delineation. For all the scanner models, acquisition parameters and reconstruction algorithms considered, the FLAB algorithm demonstrated higher robustness in delineation of the spheres with low mean errors (10%) and variability (5%), with respect to threshold-based methodologies and FCM. The repeatability provided by all segmentation algorithms considered was very high with a negligible variability of <5% in comparison to that associated with manual delineation (5-35%). The use of advanced image segmentation algorithms may not only allow high accuracy as previously demonstrated, but also provide a robust and repeatable tool to aid physicians as an initial guess in determining functional volumes in PET. (orig.)

  14. A Study of Fixed-Order Mixed Norm Designs for a Benchmark Problem in Structural Control

    Science.gov (United States)

    Whorton, Mark S.; Calise, Anthony J.; Hsu, C. C.

    1998-01-01

    This study investigates the use of H2, p-synthesis, and mixed H2/mu methods to construct full-order controllers and optimized controllers of fixed dimensions. The benchmark problem definition is first extended to include uncertainty within the controller bandwidth in the form of parametric uncertainty representative of uncertainty in the natural frequencies of the design model. The sensitivity of H2 design to unmodelled dynamics and parametric uncertainty is evaluated for a range of controller levels of authority. Next, mu-synthesis methods are applied to design full-order compensators that are robust to both unmodelled dynamics and to parametric uncertainty. Finally, a set of mixed H2/mu compensators are designed which are optimized for a fixed compensator dimension. These mixed norm designs recover the H, design performance levels while providing the same levels of robust stability as the u designs. It is shown that designing with the mixed norm approach permits higher levels of controller authority for which the H, designs are destabilizing. The benchmark problem is that of an active tendon system. The controller designs are all based on the use of acceleration feedback.

  15. Using Cut-off grade isograms to delineate ore body and calculate parameter

    International Nuclear Information System (INIS)

    Yu Yongfeng; Zhu Xiaobing; Deng Yonghui

    2014-01-01

    Taking a uranium mine for an example, using cut-off grade isograms to achieve automatic delineation of ore body and calculation of parameters are explored. With center line of catalog sampling as baseline, the number of sampling and length of sampling constructing rectangular grid and grade as elevation value, isograms of cut-off grade were drawn, thus achieving the delineation of the ore body. Then, the other parameters of the ore body can be calculated. Compared with the traditional hand drawing method, the work efficiency was greatly improved, and the material inquiry was more convenient. (authors)

  16. Homotopy Algorithm for Optimal Control Problems with a Second-order State Constraint

    International Nuclear Information System (INIS)

    Hermant, Audrey

    2010-01-01

    This paper deals with optimal control problems with a regular second-order state constraint and a scalar control, satisfying the strengthened Legendre-Clebsch condition. We study the stability of structure of stationary points. It is shown that under a uniform strict complementarity assumption, boundary arcs are stable under sufficiently smooth perturbations of the data. On the contrary, nonreducible touch points are not stable under perturbations. We show that under some reasonable conditions, either a boundary arc or a second touch point may appear. Those results allow us to design an homotopy algorithm which automatically detects the structure of the trajectory and initializes the shooting parameters associated with boundary arcs and touch points.

  17. Small Water System Management Program: 100 K Area

    International Nuclear Information System (INIS)

    Hunacek, G.S. Jr.

    1995-01-01

    Purposes of this document are: to provide an overview of the service and potable water system presently in service at the Hanford Site's 100 K Area; to provide future system forecasts based on anticipated DOE activities and programs; to delineate performance, design, and operations criteria; and to describe planned improvements. The objective of the small water system management program is to assure the water system is properly and reliably managed and operated, and continues to exist as a functional and viable entity in accordance with WAC 246-290-410

  18. On a second order of accuracy stable difference scheme for the solution of a source identification problem for hyperbolic-parabolic equations

    Science.gov (United States)

    Ashyralyyeva, Maral; Ashyraliyev, Maksat

    2016-08-01

    In the present paper, a second order of accuracy difference scheme for the approximate solution of a source identification problem for hyperbolic-parabolic equations is constructed. Theorem on stability estimates for the solution of this difference scheme and their first and second order difference derivatives is presented. In applications, this abstract result permits us to obtain the stability estimates for the solutions of difference schemes for approximate solutions of two source identification problems for hyperbolic-parabolic equations.

  19. Delineation of seismic source zones based on seismicity parameters ...

    Indian Academy of Sciences (India)

    In the present study, an attempt has been made to delineate seismic source zones in the study area (south India) based on the seismicity parameters. Seismicity parameters and the maximum probable earthquake for these source zones were evaluated and were used in the hazard evaluation. The probabilistic evaluation of ...

  20. On a k-Order System of Lyness-Type Difference Equations

    Directory of Open Access Journals (Sweden)

    G. Papaschinopoulos

    2007-07-01

    Full Text Available We consider the following system of Lyness-type difference equations: x1(n+1=(akxk(n+bk/xk−1(n−1, x2(n+1=(a1x1(n+b1/xk(n−1, xi(n+1=(ai−1xi−1(n+bi−1/xi−2(n−1, i=3,4,…,k, where ai, bi, i=1,2,…,k, are positive constants, k≥3 is an integer, and the initial values are positive real numbers. We study the existence of invariants, the boundedness, the persistence, and the periodicity of the positive solutions of this system.

  1. Existence of solutions for a fourth-order boundary value problem on the half-line via critical point theory

    Directory of Open Access Journals (Sweden)

    Mabrouk Briki

    2016-05-01

    Full Text Available In this paper, a fourth-order boundary value problem on the half-line is considered and existence of solutions is proved using a minimization principle and the mountain pass theorem.

  2. Risky procedures by nurses in hospitals: problems and (contemplated) refusals of orders by physicians, and views of physicians and nurses

    NARCIS (Netherlands)

    de Bie, J.; Cuperus-Bosma, J.M.; van der Jagt, M.A.; Gevers, J.K.M.; van der Wal, G.

    2005-01-01

    Occurrence of problems with, refusals of orders and contemplated refusals of orders for risky procedures by nurses in Dutch hospitals and views on the safety of performance was studied using postal questionnaires (600 physicians and 3200 nurses, response 60-71%). Of the respondents, 11-30%

  3. High-Order Hyperbolic Residual-Distribution Schemes on Arbitrary Triangular Grids

    Science.gov (United States)

    2015-06-22

    for efficient CFD calculations in high-order methods,3 because the grid adaptation almost necessarily introduces irregularity in the grid. In fact...problems. References 1P.A. Gnoffo. Multi-dimensional, inviscid flux reconstruction for simulation of hypersonic heating on tetrahedral grids. In Proc. of...Kitamura, E. Shima, Y. Nakamura, and P.L. Roe. Evaluation of euler fluxes for hypersonic heating computations. AIAA J., 48(4):763–776, 2010. 3Z.J. Wang, K

  4. Assessment of various strategies for 18F-FET PET-guided delineation of target volumes in high-grade glioma patients.

    Science.gov (United States)

    Vees, Hansjörg; Senthamizhchelvan, Srinivasan; Miralbell, Raymond; Weber, Damien C; Ratib, Osman; Zaidi, Habib

    2009-02-01

    The purpose of the study is to assess the contribution of (18)F-fluoro-ethyl-tyrosine ((18)F-FET) positron emission tomography (PET) in the delineation of gross tumor volume (GTV) in patients with high-grade gliomas compared with magnetic resonance imaging (MRI) alone. The study population consisted of 18 patients with high-grade gliomas. Seven image segmentation techniques were used to delineate (18)F-FET PET GTVs, and the results were compared to the manual MRI-derived GTV (GTV(MRI)). PET image segmentation techniques included manual delineation of contours (GTV(man)), a 2.5 standardized uptake value (SUV) cutoff (GTV(2.5)), a fixed threshold of 40% and 50% of the maximum signal intensity (GTV(40%) and GTV(50%)), signal-to-background ratio (SBR)-based adaptive thresholding (GTV(SBR)), gradient find (GTV(GF)), and region growing (GTV(RG)). Overlap analysis was also conducted to assess geographic mismatch between the GTVs delineated using the different techniques. Contours defined using GTV(2.5) failed to provide successful delineation technically in three patients (18% of cases) as SUV(max) segmentation algorithm is crucial, since it impacts both the volume and shape of the resulting GTV. The 2.5 SUV isocontour and GF segmentation techniques performed poorly and should not be used for GTV delineation. With adequate setting, the SBR-based PET technique may add considerably to conventional MRI-guided GTV delineation.

  5. On Advice Complexity of the k-server Problem under Sparse Metrics

    DEFF Research Database (Denmark)

    Gupta, S.; Kamali, S.; López-Ortiz, A.

    2013-01-01

    O (n(log μ +log logN)) bits of advice. Among other results, this gives a 3-competitive algorithm for planar graphs, provided with O (n log log N) bits of advice. On the other side, we show that an advice of size Ω (n) is required to obtain a 1-competitive algorithm for sequences of size n even......We consider the k-Server problem under the advice model of computation when the underlying metric space is sparse. On one side, we introduce Θ (1)-competitive algorithms for a wide range of sparse graphs, which require advice of (almost) linear size. Namely, we show that for graphs of size N...... and treewidth α, there is an online algorithm which receives O (n(log α +log log N))1 bits of advice and optimally serves a sequence of length n. With a different argument, we show that if a graph admits a system of μ collective tree (q, r)- spanners, then there is a (q + r)-competitive algorithm which receives...

  6. Psychological profile: the problem of modeling the unknown criminal personality

    Directory of Open Access Journals (Sweden)

    Г. М. Гетьман

    2013-10-01

    Full Text Available The article investigates the problem of modeling an unknown person in the preparation of criminal psychological profile. Some approaches to the concept of "psychological profile" and "psychological portrait", in particular the proposed delineation of these terms. We consider the system steps in the development of the psychological profile of an unknown perpetrator.

  7. Group theoretic derivation of angular functions for the non-relativistic A-body problem in the K-harmonics approach

    International Nuclear Information System (INIS)

    Alcaras, J.A.C.; Ferreira, J.L.

    1975-01-01

    A derivation of an angular basis for the A-body problem, suitable for the K-harmonics method, is presented. Those angular functions are obtained from homogeneous and harmonic polynomials, which are completely specified by labels associated to eigenvalues of the Casimir invariants of subgroups of the 3(A-1)-dimensional orthogonal group, among them, the total angular momentum and its z-projection [pt

  8. Robust, fully automatic delineation of the head contour by stereotactical normalization for attenuation correction according to Chang in dopamine transporter scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Lange, Catharina; Brenner, Winfried; Buchert, Ralph [Charite - Universitaetsmedizin Berlin, Department of Nuclear Medicine, Berlin (Germany); Kurth, Jens; Schwarzenboeck, Sarah; Krause, Bernd J. [Universitaetsmedizin Rostock, Department of Nuclear Medicine, Rostock (Germany); Seese, Anita; Steinhoff, Karen; Sabri, Osama; Hesse, Swen [Universitaetsklinikum Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Umland-Seidler, Bert [GE Healthcare Buchler GmbH and Co. KG, Munich (Germany)

    2015-09-15

    Chang's method, the most widely used attenuation correction (AC) in brain single-photon emission computed tomography (SPECT), requires delineation of the outer contour of the head. Manual and automatic threshold-based methods are prone to errors due to variability of tracer uptake in the scalp. The present study proposes a new method for fully automated delineation of the head based on stereotactical normalization. The method was validated for SPECT with I-123-ioflupane. The new method was compared to threshold-based delineation in 62 unselected patients who had received I-123-ioflupane SPECT at one of 3 centres. The impact on diagnostic power was tested for semi-quantitative analysis and visual reading of the SPECT images (six independent readers). The two delineation methods produced highly consistent semi-quantitative results. This was confirmed by receiver operating characteristic analyses in which the putamen specific-to-background ratio achieved highest area under the curve with negligible effect of the delineation method: 0.935 versus 0.938 for stereotactical normalization and threshold-based delineation, respectively. Visual interpretation of DVR images was also not affected by the delineation method. Delineation of the head contour by stereotactical normalization appears useful for Chang AC in I-123-ioflupane SPECT. It is robust and does not require user interaction. (orig.)

  9. Characterization of spin-on-glass very-low-k polymethylsiloxane with copper metallization

    International Nuclear Information System (INIS)

    Aw, K.C.; Salim, N.T.; Gao, W.; Li, Z.

    2006-01-01

    Cu diffusion is one major problem that inhibits low-k dielectric to be integrated with existing fabrication technology effectively. This paper demonstrates the effects of surface modification towards polymethylsiloxane low-k dielectric (LKD 5109) from JSR Micro using gas mixture of H 2 + N 2 plasma in order to improve Cu diffusion barrier. C-V plots indirectly indicated that plasma treatment reduces Cu + ions penetration during Cu deposition using magnetron sputtering. XPS confirmed that short duration (10 to 30 s) of H 2 + N 2 plasma treatment could cause surface densification of LKD 5109 low-k thin film through formation of N-C bonds. However, the negative effect of plasma treatment is the increment of dielectric constant (k) due to possible surface densification

  10. A generalized methodology for identification of threshold for HRU delineation in SWAT model

    Science.gov (United States)

    M, J.; Sudheer, K.; Chaubey, I.; Raj, C.

    2016-12-01

    The distributed hydrological model, Soil and Water Assessment Tool (SWAT) is a comprehensive hydrologic model widely used for making various decisions. The simulation accuracy of the distributed hydrological model differs due to the mechanism involved in the subdivision of the watershed. Soil and Water Assessment Tool (SWAT) considers sub-dividing the watershed and the sub-basins into small computing units known as 'hydrologic response units (HRU). The delineation of HRU is done based on unique combinations of land use, soil types, and slope within the sub-watersheds, which are not spatially defined. The computations in SWAT are done at HRU level and are then aggregated up to the sub-basin outlet, which is routed through the stream system. Generally, the HRUs are delineated by considering a threshold percentage of land use, soil and slope are to be given by the modeler to decrease the computation time of the model. The thresholds constrain the minimum area for constructing an HRU. In the current HRU delineation practice in SWAT, the land use, soil and slope of the watershed within a sub-basin, which is less than the predefined threshold, will be surpassed by the dominating land use, soil and slope, and introduce some level of ambiguity in the process simulations in terms of inappropriate representation of the area. But the loss of information due to variation in the threshold values depends highly on the purpose of the study. Therefore this research studies the effects of threshold values of HRU delineation on the hydrological modeling of SWAT on sediment simulations and suggests guidelines for selecting the appropriate threshold values considering the sediment simulation accuracy. The preliminary study was done on Illinois watershed by assigning different thresholds for land use and soil. A general methodology was proposed for identifying an appropriate threshold for HRU delineation in SWAT model that considered computational time and accuracy of the simulation

  11. Delineating active faults by using integrated geophysical data at northeastern part of Cairo, Egypt

    Directory of Open Access Journals (Sweden)

    Sultan Awad Sultan Araffa

    2012-06-01

    Full Text Available Geophysical techniques such as gravity, magnetic and seismology are perfect tools for detecting subsurface structures of local, regional as well as of global scales. The study of the earthquake records can be used for differentiating the active and non active fault elements. In the current study more than 2200 land magnetic stations have been measured by using two proton magnetometers. The data is corrected for diurnal variations and then reduced by IGRF. The corrected data have been interpreted by different techniques after filtering the data to separate shallow sources (basaltic sheet from the deep sources (basement complex. Both Euler deconvolution and 3-D magnetic modeling have been carried out. The results of our interpretation have indicated that the depth to the upper surface of basaltic sheet ranges from less than 10–600 m, depth to the lower surface ranges from 60 to 750 m while the thickness of the basaltic sheet varies from less than 10–450 m. Moreover, gravity measurements have been conducted at the 2200 stations using a CG-3 gravimeter. The measured values are corrected to construct a Bouguer anomaly map. The least squares technique is then applied for regional residual separation. The third order of least squares is found to be the most suitable to separate the residual anomalies from the regional one. The resultant third order residual gravity map is used to delineate the structural fault systems of different characteristic trends. The trends are a NW–SE trend parallel to that of Gulf of Suez, a NE–SW trend parallel to the Gulf of Aqaba and an E–W trend parallel to the trend of Mediterranean Sea. Taking seismological records into consideration, it is found that most of 24 earthquake events recorded in the study area are located on fault elements. This gives an indication that the delineated fault elements are active.

  12. An Optimal Order Nonnested Mixed Multigrid Method for Generalized Stokes Problems

    Science.gov (United States)

    Deng, Qingping

    1996-01-01

    A multigrid algorithm is developed and analyzed for generalized Stokes problems discretized by various nonnested mixed finite elements within a unified framework. It is abstractly proved by an element-independent analysis that the multigrid algorithm converges with an optimal order if there exists a 'good' prolongation operator. A technique to construct a 'good' prolongation operator for nonnested multilevel finite element spaces is proposed. Its basic idea is to introduce a sequence of auxiliary nested multilevel finite element spaces and define a prolongation operator as a composite operator of two single grid level operators. This makes not only the construction of a prolongation operator much easier (the final explicit forms of such prolongation operators are fairly simple), but the verification of the approximate properties for prolongation operators is also simplified. Finally, as an application, the framework and technique is applied to seven typical nonnested mixed finite elements.

  13. Solving the linearized forward-speed radiation problem using a high-order finite difference method on overlapping grids

    DEFF Research Database (Denmark)

    Amini Afshar, Mostafa; Bingham, Harry B.

    2017-01-01

    . Frequency-domain results are then obtained from a Fourier transform of the force and motion signals. In order to make a robust Fourier transform, and capture the response around the critical frequency, the tail of the force signal is asymptotically extrapolated assuming a linear decay rate. Fourth......The linearized potential flow approximation for the forward speed radiation problem is solved in the time domain using a high-order finite difference method. The finite-difference discretization is developed on overlapping, curvilinear body-fitted grids. To ensure numerical stability...

  14. Positive solutions for a fourth order boundary value problem

    Directory of Open Access Journals (Sweden)

    Bo Yang

    2005-02-01

    Full Text Available We consider a boundary value problem for the beam equation, in which the boundary conditions mean that the beam is embedded at one end and free at the other end. Some new estimates to the positive solutions to the boundary value problem are obtained. Some sufficient conditions for the existence of at least one positive solution for the boundary value problem are established. An example is given at the end of the paper to illustrate the main results.

  15. On generalized operator quasi-equilibrium problems

    Science.gov (United States)

    Kum, Sangho; Kim, Won Kyu

    2008-09-01

    In this paper, we will introduce the generalized operator equilibrium problem and generalized operator quasi-equilibrium problem which generalize the operator equilibrium problem due to Kazmi and Raouf [K.R. Kazmi, A. Raouf, A class of operator equilibrium problems, J. Math. Anal. Appl. 308 (2005) 554-564] into multi-valued and quasi-equilibrium problems. Using a Fan-Browder type fixed point theorem in [S. Park, Foundations of the KKM theory via coincidences of composites of upper semicontinuous maps, J. Korean Math. Soc. 31 (1994) 493-519] and an existence theorem of equilibrium for 1-person game in [X.-P. Ding, W.K. Kim, K.-K. Tan, Equilibria of non-compact generalized games with L*-majorized preferences, J. Math. Anal. Appl. 164 (1992) 508-517] as basic tools, we prove new existence theorems on generalized operator equilibrium problem and generalized operator quasi-equilibrium problem which includes operator equilibrium problems.

  16. Methods for Delineating Degraded Land at Citarum Watershed, West Java, Indonesia

    Directory of Open Access Journals (Sweden)

    Suria Darma Tarigan

    2012-09-01

    Full Text Available Accurate information on the extent and spatial location of degraded lands is very important to plan their rehabilitation.So far, various institutions issue different estimation on the extent of degraded land in Indonesia led to big confusion for rehabilitation planning. Ministry of Forestry estimates around 30.2 million ha of degraded land both inside and outside forestry area throughout Indonesia based on data released in 2007. Ministry of Forestry implementes the socalled scoring method in delineating degraded land. Criteria used in the scoring methods are: land cover, slope steepness, erosion, and management. Scoring method applies different weight to each of those criteria. This study aimed to analyze accuracy of scoring method and to compare it to propose alternative methods in delineating degraded land such as: a Inconsistency of land use, and b Combination of Inconsistency of land use and scoring method. The accuracy of these methods were obtained by comparing to the field observation. The slope map was derived from SRTM 30 m, soil map was obtained from Soil Research Institute and land cover/land use from Ministry for Environment. Using GIS analysis, those maps were used to compose land capability classification (LCC and inconsistency of land use. The study showed that scoring method had 66% accuracy in delineating degraded land. When scoring method was combined with Inconsistency method the accuracy increased about 7%.

  17. A scheme to calculate higher-order homogenization as applied to micro-acoustic boundary value problems

    Science.gov (United States)

    Vagh, Hardik A.; Baghai-Wadji, Alireza

    2008-12-01

    Current technological challenges in materials science and high-tech device industry require the solution of boundary value problems (BVPs) involving regions of various scales, e.g. multiple thin layers, fibre-reinforced composites, and nano/micro pores. In most cases straightforward application of standard variational techniques to BVPs of practical relevance necessarily leads to unsatisfactorily ill-conditioned analytical and/or numerical results. To remedy the computational challenges associated with sub-sectional heterogeneities various sophisticated homogenization techniques need to be employed. Homogenization refers to the systematic process of smoothing out the sub-structural heterogeneities, leading to the determination of effective constitutive coefficients. Ordinarily, homogenization involves a sophisticated averaging and asymptotic order analysis to obtain solutions. In the majority of the cases only zero-order terms are constructed due to the complexity of the processes involved. In this paper we propose a constructive scheme for obtaining homogenized solutions involving higher order terms, and thus, guaranteeing higher accuracy and greater robustness of the numerical results. We present

  18. Electromagnetic mass splittings of π, a1, K, K1(1400), and K* (892)

    International Nuclear Information System (INIS)

    Gao, D.; Li, B.A.; Yan, M.

    1997-01-01

    To one-loop order and O(α EM ), the electromagnetic mass splittings of π, a 1 , K, K 1 (1400), and K * (892) are calculated in the framework of U(3) L xU(3) R chiral field theory. The logarithmic divergences emerging in the Feynman integrations of the mesonic loops are factorized by using an intrinsic parameter g of this theory. No other additional parameters or counterterms are introduced to absorb the mesonic loop divergences. When f π , m ρ , and m a are taken as inputs, the parameter g will be determined and all the physical results are finite and fixed. Dashen's theorem is satisfied in the chiral SU(3) limit of this theory and a rather large violation of the theorem is revealed at the order of m s or m K 2 . Mass ratios of light quarks have been determined. A relation for electromagnetic corrections to masses of axial-vector mesons is obtained. It could be regarded as a generalization of Dashen's theorem. Comparing with data, it is found that the nonelectromagnetic mass difference of K * is in agreement with the estimation of Schechter, Subbaraman, and Weigel. copyright 1997 The American Physical Society

  19. Geographic object-based delineation of neighborhoods of Accra, Ghana using QuickBird satellite imagery.

    Science.gov (United States)

    Stow, Douglas A; Lippitt, Christopher D; Weeks, John R

    2010-08-01

    The objective was to test GEographic Object-based Image Analysis (GEOBIA) techniques for delineating neighborhoods of Accra, Ghana using QuickBird multispectral imagery. Two approaches to aggregating census enumeration areas (EAs) based on image-derived measures of vegetation objects were tested: (1) merging adjacent EAs according to vegetation measures and (2) image segmentation. Both approaches exploit readily available functions within commercial GEOBIA software. Image-derived neighborhood maps were compared to a reference map derived by spatial clustering of slum index values (from census data), to provide a relative assessment of potential map utility. A size-constrained iterative segmentation approach to aggregation was more successful than standard image segmentation or feature merge techniques. The segmentation approaches account for size and shape characteristics, enabling more realistic neighborhood boundaries to be delineated. The percentage of vegetation patches within each EA yielded more realistic delineation of potential neighborhoods than mean vegetation patch size per EA.

  20. SENSMG: First-Order Sensitivities of Neutron Reaction Rates, Reaction-Rate Ratios, Leakage, keff, and α Using PARTISN

    Energy Technology Data Exchange (ETDEWEB)

    Favorite, Jeffrey A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-21

    SENSMG is a tool for computing first-order sensitivities of neutron reaction rates, reaction-rate ratios, leakage, keff, and α using the PARTISN multigroup discrete-ordinates code. SENSMG computes sensitivities to all of the transport cross sections and data (total, fission, nu, chi, and all scattering moments), two edit cross sections (absorption and capture), and the density for every isotope and energy group. It also computes sensitivities to the mass density for every material and derivatives with respect to all interface locations. The tool can be used for one-dimensional spherical (r) and two-dimensional cylindrical (r-z) geometries. The tool can be used for fixed-source and eigenvalue problems. The tool implements Generalized Perturbation Theory (GPT) as discussed by Williams and Stacey. Section II of this report describes the theory behind adjoint-based sensitivities, gives the equations that SENSMG solves, and defines the sensitivities that are output. Section III describes the user interface, including the input file and command line options. Section IV describes the output. Section V gives some notes about the coding that may be of interest. Section VI discusses verification, which is ongoing. Section VII lists needs and ideas for future work. Appendix A lists all of the input files whose results are presented in Sec. VI.

  1. On a kind of Noether symmetries and conservation laws in k-cosymplectic field theory

    International Nuclear Information System (INIS)

    Marrero, Juan Carlos; Roman-Roy, Narciso; Salgado, Modesto; Vilarino, Silvia

    2011-01-01

    This paper is devoted to studying symmetries of certain kinds of k-cosymplectic Hamiltonian systems in first-order classical field theories. Thus, we introduce a particular class of symmetries and study the problem of associating conservation laws to them by means of a suitable generalization of Noether's theorem.

  2. Magnetic short range order in Gd

    International Nuclear Information System (INIS)

    Child, H.R.

    1976-01-01

    Quasielastic neutron scattering has been used to investigate magnetic short range order in Gd for 80 0 K 0 K. Short range order exists throughout this range from well below T/sub C/ = 291 0 K to well above it and can be reasonably well described by an anisotropic Orstein-Zernike form for chi

  3. A local contrast based approach to threshold segmentation for PET target volume delineation

    International Nuclear Information System (INIS)

    Drever, Laura; Robinson, Don M.; McEwan, Alexander; Roa, Wilson

    2006-01-01

    Current radiation therapy techniques, such as intensity modulated radiation therapy and three-dimensional conformal radiotherapy rely on the precise delivery of high doses of radiation to well-defined volumes. CT, the imaging modality that is most commonly used to determine treatment volumes cannot, however, easily distinguish between cancerous and normal tissue. The ability of positron emission tomography (PET) to more readily differentiate between malignant and healthy tissues has generated great interest in using PET images to delineate target volumes for radiation treatment planning. At present the accurate geometric delineation of tumor volumes is a subject open to considerable interpretation. The possibility of using a local contrast based approach to threshold segmentation to accurately delineate PET target cross sections is investigated using well-defined cylindrical and spherical volumes. Contrast levels which yield correct volumetric quantification are found to be a function of the activity concentration ratio between target and background, target size, and slice location. Possibilities for clinical implementation are explored along with the limits posed by this form of segmentation

  4. Air Traffic ControL : FAA Order 7110.65K

    Science.gov (United States)

    1997-07-17

    This order prescribes air traffic control procedures and phraseology for use by : personnel providing air traffic control services. Controllers are required to : be familiar with the provisions of this order that pertain to their operational : respon...

  5. Differential and Difference Boundary Value Problem for Loaded Third-Order Pseudo-Parabolic Differential Equations and Difference Methods for Their Numerical Solution

    Science.gov (United States)

    Beshtokov, M. Kh.

    2017-12-01

    Boundary value problems for loaded third-order pseudo-parabolic equations with variable coefficients are considered. A priori estimates for the solutions of the problems in the differential and difference formulations are obtained. These a priori estimates imply the uniqueness and stability of the solution with respect to the initial data and the right-hand side on a layer, as well as the convergence of the solution of each difference problem to the solution of the corresponding differential problem.

  6. Enhancing Higher Order Thinking Skills In A Marine Biology Class Through Problem-Based Learning

    Directory of Open Access Journals (Sweden)

    Richard M. Magsino

    2014-10-01

    Full Text Available The purpose of this research was to examine students' perspectives of their learning in marine biology in the collaborative group context of Problem-based Learning (PBL. Students’ higher order thinking skills (HOTS using PBL involves the development of their logical thinking and reasoning abilities which stimulates their curiosity and associative thinking. This study aimed to investigate how critical thinking skills, particularly analysis, synthesis and evaluation were enhanced in a marine biology class through PBL. Qualitative research approach was used to examine student responses in a questionnaire involving 10 open-ended questions that target students’ HOTS on a problem presented in a marine biology class for BS Biology students. Using axial coding as a qualitative data analysis technique by which grounded theory can be performed, the study was able to determine how students manifest their higher reasoning abilities when confronted with a marine biology situation. Results show student responses yielding affirmative remarks on the 10 questions intended to know their level of analysis (e.g., analyzing, classifying, inferring, discriminating and relating or connecting, synthesis (e.g., synthesizing and collaborating, and evaluation (e.g., comparing, criticizing, and convincing of information from the presented marine biology problem. Consequently, students were able to effectively design experiments to address the presented issue through problem-based learning. Results of the study show that PBL is an efficient instructional strategy embedded within a conventional curriculum used to develop or enhance critical thinking in marine biology.

  7. Sensitivity of Optimal Solutions to Control Problems for Second Order Evolution Subdifferential Inclusions.

    Science.gov (United States)

    Bartosz, Krzysztof; Denkowski, Zdzisław; Kalita, Piotr

    In this paper the sensitivity of optimal solutions to control problems described by second order evolution subdifferential inclusions under perturbations of state relations and of cost functionals is investigated. First we establish a new existence result for a class of such inclusions. Then, based on the theory of sequential [Formula: see text]-convergence we recall the abstract scheme concerning convergence of minimal values and minimizers. The abstract scheme works provided we can establish two properties: the Kuratowski convergence of solution sets for the state relations and some complementary [Formula: see text]-convergence of the cost functionals. Then these two properties are implemented in the considered case.

  8. Perturbation on diffusion problems in domain with interfaces

    International Nuclear Information System (INIS)

    Watson, F.V.

    1985-01-01

    A perturbative type algorithm for the solution of linear diffusion equation at two dimensions, in domain with interfaces is presented. The perturbative scheme should be assembled in the weak formulation of diffusion equation, even if the strong solution exists, and when it is taken in terms superiors to first order, it should be calculated analytically, in one of the dimensions to avoid problems of slow convergence. (M.C.K.) [pt

  9. Clinical target volume delineation including elective nodal irradiation in preoperative and definitive radiotherapy of pancreatic cancer

    Directory of Open Access Journals (Sweden)

    Caravatta Luciana

    2012-06-01

    Full Text Available Abstract Background Radiotherapy (RT is widely used in the treatment of pancreatic cancer. Currently, recommendation has been given for the delineation of the clinical target volume (CTV in adjuvant RT. Based on recently reviewed pathologic data, the aim of this study is to propose criteria for the CTV definition and delineation including elective nodal irradiation (ENI in the preoperative and definitive treatment of pancreatic cancer. Methods The anatomical structures of interest, as well as the abdominal vasculature were identified on intravenous contrast-enhanced CT scans of two different patients with pancreatic cancer of the head and the body. To delineate the lymph node area, a margin of 10 mm was added to the arteries. Results We proposed a set of guidelines for elective treatment of high-risk nodal areas and CTV delineation. Reference CT images were provided. Conclusions The proposed guidelines could be used for preoperative or definitive RT for carcinoma of the head and body of the pancreas. Further clinical investigations are needed to validate the defined CTVs.

  10. Target volume delineation and field setup. A practical guide for conformal and intensity-modulated radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Nancy Y. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States). Radiation Oncology; Lu, Jiade J. (eds.) [National Univ. Health System, Singapore (Singapore). Dept. of Radiation Oncology; National Univ. of Singapore (Singapore). Dept. of Medicine

    2013-03-01

    Practical handbook on selection and delineation of tumor volumes and fields for conformal radiation therapy, including IMRT. Helpful format facilitating use on a step-by-step basis in daily practice. Designed to ensure accurate coverage of commonly encountered tumors along their routes of spread. This handbook is designed to enable radiation oncologists to appropriately and confidently delineate tumor volumes/fields for conformal radiation therapy, including intensity-modulated radiation therapy (IMRT), in patients with commonly encountered cancers. The orientation of this handbook is entirely practical, in that the focus is on the illustration of clinical target volume (CTV) delineation for each major malignancy. Each chapter provides guidelines and concise knowledge on CTV selection for a particular disease, explains how the anatomy of lymphatic drainage shapes the selection of the target volume, and presents detailed illustrations of volumes, slice by slice, on planning CT images. While the emphasis is on target volume delineation for three-dimensional conformal therapy and IMRT, information is also provided on conventional radiation therapy field setup and planning for certain malignancies for which IMRT is not currently suitable.

  11. Renormalization as an extension problem on the Count our ordered formalism in FFTF

    Energy Technology Data Exchange (ETDEWEB)

    Franco, D.H.T. [Centro de Estudos de Fisica Teorica (CEFT), Belo Horizonte, MG (Brazil); Acebal, J.L. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas; Grupo de Fisica Teorica Jose Leite Lopes (GFT-JLL), Petropolis, RJ (Brazil)

    2003-06-01

    From a distributional-theoretical framework, we make efforts in order to fill a gap in the series of studies which discuss the inheritance of the renormalization behaviour of a finite temperature field theory (FTFT) from the analogous version in quantum field theory (QFT) at T=0. Renormalization is treated as a distributional extension problem having the mathematical structure disentangled as much as possible from the physical aspects. The purely technical details essential for the discussion are briefly reviewed in a handle manner for further theoretical physics applications. The analysis elucidates some qualitative and quantitative distinctions concerning the divergences in the perturbation series when it is considered the FTFT version associated to a given QFT. Despite the differences, it turns clear the reason why the leading ultraviolet behaviour keeps unaffected when it is considered the FTFT version associated to a given QFT. The study is model independent and the approach allows one to consider the FTFT both imaginary and real time formalism at once in a unified way in the contour ordered formalism. (author)

  12. An adaptive singular ES-FEM for mechanics problems with singular field of arbitrary order

    OpenAIRE

    Nguyen-Xuan, H.; Liu, G. R.; Bordas, Stéphane; Natarajan, S.; Rabczuk, T.

    2013-01-01

    This paper presents a singular edge-based smoothed finite element method (sES-FEM) for mechanics problems with singular stress fields of arbitrary order. The sES-FEM uses a basic mesh of three-noded linear triangular (T3) elements and a special layer of five-noded singular triangular elements (sT5) connected to the singular-point of the stress field. The sT5 element has an additional node on each of the two edges connected to the singular-point. It allows us to represent simple and efficient ...

  13. Positive solutions with changing sign energy to a nonhomogeneous elliptic problem of fourth order

    Directory of Open Access Journals (Sweden)

    M.Talbi

    2011-01-01

    Full Text Available In this paper, we study the existence for two positive solutions toa nonhomogeneous elliptic equation of fourth order with a parameter lambda such tha 0 < lambda < lambda^. The first solution has a negative energy while the energy of the second one is positive for 0 < lambda < lambda_0 and negative for lambda_0 < lambda < lambda^. The values lambda_0 and lambda^ are given under variational form and we show that every corresponding critical point is solution of the nonlinear elliptic problem (with a suitable multiplicative term.

  14. Bayesian Simultaneous Estimation for Means in k Sample Problems

    OpenAIRE

    Imai, Ryo; Kubokawa, Tatsuya; Ghosh, Malay

    2017-01-01

    This paper is concerned with the simultaneous estimation of k population means when one suspects that the k means are nearly equal. As an alternative to the preliminary test estimator based on the test statistics for testing hypothesis of equal means, we derive Bayesian and minimax estimators which shrink individual sample means toward a pooled mean estimator given under the hypothesis. Interestingly, it is shown that both the preliminary test estimator and the Bayesian minimax shrinkage esti...

  15. Classical solutions of mixed problems for quasilinear first order PFDEs on a cylindrical domain

    Directory of Open Access Journals (Sweden)

    Wojciech Czernous

    2014-01-01

    Full Text Available We abandon the setting of the domain as a Cartesian product of real intervals, customary for first order PFDEs (partial functional differential equations with initial boundary conditions. We give a new set of conditions on the possibly unbounded domain \\(\\Omega\\ with Lipschitz differentiable boundary. Well-posedness is then reliant on a variant of the normal vector condition. There is a neighbourhood of \\(\\partial\\Omega\\ with the property that if a characteristic trajectory has a point therein, then its every earlier point lies there as well. With local assumptions on coefficients and on the free term, we prove existence and Lipschitz dependence on data of classical solutions on \\((0,c\\times\\Omega\\ to the initial boundary value problem, for small \\(c\\. Regularity of solutions matches this domain, and the proof uses the Banach fixed-point theorem. Our general model of functional dependence covers problems with deviating arguments and integro-differential equations.

  16. Pattern-Guided k-Anonymity

    Directory of Open Access Journals (Sweden)

    Rolf Niedermeier

    2013-10-01

    Full Text Available We suggest a user-oriented approach to combinatorial data anonymization. A data matrix is called k-anonymous if every row appears at least k times—the goal of the NP-hard k-ANONYMITY problem then is to make a given matrix k-anonymous by suppressing (blanking out as few entries as possible. Building on previous work and coping with corresponding deficiencies, we describe an enhanced k-anonymization problem called PATTERN-GUIDED k-ANONYMITY, where the users specify in which combinations suppressions may occur. In this way, the user of the anonymized data can express the differing importance of various data features. We show that PATTERN-GUIDED k-ANONYMITY is NP-hard. We complement this by a fixed-parameter tractability result based on a “data-driven parameterization” and, based on this, develop an exact integer linear program (ILP-based solution method, as well as a simple, but very effective, greedy heuristic. Experiments on several real-world datasets show that our heuristic easily matches up to the established “Mondrian” algorithm for k-ANONYMITY in terms of the quality of the anonymization and outperforms it in terms of running time.

  17. Some aspects of the inverse problem for general first order systems

    International Nuclear Information System (INIS)

    Sarlet, W.; Cantrijn, F.

    1978-01-01

    In this paper we investigate the most general systems of first-order ordinary differential equations which satisfy the integrability conditions of the inverse problem for canonical formulations, i.e., are derivable from a variational principle. It is shown that they have a structure which is invariant under arbitrary coordinate-transformations. A special class of transformations, called identity-isotopic transformations, is described. It is illustrated how these transformations share all properties with classical canonical transformations except one: the solutions of the system, viewed as transformations from the set of initial values, generally are not identity-isotopic. This failure is shown to be due to the explicit time-dependence of the functions which characterise the system, and the special role of this time-dependence is further clarified using the possibility of a reduction to conventional Hamiltonian systems. All properties are derived here within the framework of an analytic treatment of a system of differential equations

  18. The Ordered Capacitated Multi-Objective Location-Allocation Problem for Fire Stations Using Spatial Optimization

    Directory of Open Access Journals (Sweden)

    Samira Bolouri

    2018-01-01

    Full Text Available Determining the positions of facilities, and allocating demands to them, is a vitally important problem. Location-allocation problems are optimization NP-hard procedures. This article evaluates the ordered capacitated multi-objective location-allocation problem for fire stations, using simulated annealing and a genetic algorithm, with goals such as minimizing the distance and time as well as maximizing the coverage. After tuning the parameters of the algorithms using sensitivity analysis, they were used separately to process data for Region 11, Tehran. The results showed that the genetic algorithm was more efficient than simulated annealing, and therefore, the genetic algorithm was used in later steps. Next, we increased the number of stations. Results showed that the model can successfully provide seven optimal locations and allocate high demands (280,000 to stations in a discrete space in a GIS, assuming that the stations’ capacities are known. Following this, we used a weighting program so that in each repetition, we could allot weights to each target randomly. Finally, by repeating the model over 10 independent executions, a set of solutions with the least sum and the highest number of non-dominated solutions was selected from among many non-dominated solutions as the best set of optimal solutions.

  19. Increasing participation in the Earth sciences through engagement of K-12 educators in Earth system science analysis, inquiry and problem- based learning and teaching

    Science.gov (United States)

    Burrell, S.

    2012-12-01

    Given low course enrollment in geoscience courses, retention in undergraduate geoscience courses, and granting of BA and advanced degrees in the Earth sciences an effective strategy to increase participation in this field is necessary. In response, as K-12 education is a conduit to college education and the future workforce, Earth science education at the K-12 level was targeted with the development of teacher professional development around Earth system science, inquiry and problem-based learning. An NSF, NOAA and NASA funded effort through the Institute for Global Environmental Strategies led to the development of the Earth System Science Educational Alliance (ESSEA) and dissemination of interdisciplinary Earth science content modules accessible to the public and educators. These modules formed the basis for two teacher workshops, two graduate level courses for in-service teachers and two university course for undergraduate teacher candidates. Data from all three models will be presented with emphasis on the teacher workshop. Essential components of the workshop model include: teaching and modeling Earth system science analysis; teacher development of interdisciplinary, problem-based academic units for implementation in the classroom; teacher collaboration; daily workshop evaluations; classroom observations; follow-up collaborative meetings/think tanks; and the building of an on-line professional community for continued communication and exchange of best practices. Preliminary data indicate increased understanding of Earth system science, proficiency with Earth system science analysis, and renewed interest in innovative delivery of content amongst teachers. Teacher-participants reported increased student engagement in learning with the implementation of problem-based investigations in Earth science and Earth system science thinking in the classroom, however, increased enthusiasm of the teacher acted as a contributing factor. Teacher feedback on open

  20. Production of charged sigma-hyperons in 4.2 GeV/c K-p interactions

    International Nuclear Information System (INIS)

    Groot, A.J. de

    1975-01-01

    Results from a 4.2 GeV/c K - p experiment are presented. In a general review of the experiment particular attention is paid to the scanning procedure. Problems connected with charged decays (kinks) are dealt with. Modifications are treated that have been implemented in the kinematical fitting programme in order to improve the pass rate of events with a straight hyperon-track. Geometrical losses for kinks and ways to correct for them are discussed. Reactions of the type K - p→0 - 1/2 + are considered and Veneziano models for K - p→Σ + π - and K - p→Σ + π - π 0 . A new B 5 -approach is made to the reaction K - p→Σ + π - π 0 , using a five-point function. (V.J.C.)

  1. Detection and delineation of underground septic tanks in sandy terrain using ground penetrating radar

    Science.gov (United States)

    Omolaiye, Gabriel Efomeh; Ayolabi, Elijah A.

    2010-09-01

    A ground penetrating radar (GPR) survey was conducted on the Lekki Peninsula, Lagos State, Nigeria. The primary target of the survey was the delineation of underground septic tanks (ST). A total of four GPR profiles were acquired on the survey site using Ramac X3M GPR equipment with a 250MHz antenna, chosen based on the depth of interest and resolution. An interpretable depth of penetration of 4.5m below the surface was achieved after processing. The method accurately delineated five underground ST. The tops of the ST were easily identified on the radargram based on the strong-amplitude anomalies, the length and the depths to the base of the ST were estimated with 99 and 73 percent confidence respectively. The continuous vertical profiles provide uninterrupted subsurface data along the lines of traverse, while the non-intrusive nature makes it an ideal tool for the accurate mapping and delineation of underground utilities.

  2. 11C-methionine PET improves the target volume delineation of meningiomas treated with stereotactic fractionated radiotherapy

    International Nuclear Information System (INIS)

    Grosu, Anca-Ligia; Weber, Wolfgang A.; Astner, Sabrina T.; Adam, Markus; Krause, Bernd J.; Schwaiger, Markus; Molls, Michael; Nieder, Carsten

    2006-01-01

    Purpose: To evaluate the role of 11 C-methionine positron emission tomography (MET-PET) in target volume delineation for meningiomas and to determine the interobserver variability. Methods and Materials: Two independent observers performed treatment planning in 10 patients according to a prospective written protocol. In the first step, they used coregistered computed tomography (CT) and magnetic resonance imaging (MRI). In the second step, MET-PET was added to CT/MRI (image fusion based on mutual information). Results: The correlation between gross tumor volume (GTVs) delineated by the two observers based on CT/MRI was r = 0.855 (Spearman's correlation coefficient, p = 0.002) and r = 0.988 (p = 0.000) when MET-PET/CT/MRI were used. The number of patients with agreement in more then 80% of the outlined volume increased with the availability of MET-PET from 1 in 10 to 5 in 10. The median volume of intersection between the regions delineated by two observers increased significantly from 69% (from the composite volume) to 79%, by the addition of MET-PET (p = 0.005). The information of MET-PET was useful to delineate GTV in the area of cavernous sinus, orbit, and base of the skull. Conclusions: The hypothesis-generating findings of potential normal tissue sparing and reduced interobserver variability provide arguments for invasive studies of the correlation between MET-PET images and histologic tumor extension and for prospective trials of target volume delineation with CT/MRI/MET-PET image fusion

  3. Optimizing landslide susceptibility zonation: Effects of DEM spatial resolution and slope unit delineation on logistic regression models

    Science.gov (United States)

    Schlögel, R.; Marchesini, I.; Alvioli, M.; Reichenbach, P.; Rossi, M.; Malet, J.-P.

    2018-01-01

    We perform landslide susceptibility zonation with slope units using three digital elevation models (DEMs) of varying spatial resolution of the Ubaye Valley (South French Alps). In so doing, we applied a recently developed algorithm automating slope unit delineation, given a number of parameters, in order to optimize simultaneously the partitioning of the terrain and the performance of a logistic regression susceptibility model. The method allowed us to obtain optimal slope units for each available DEM spatial resolution. For each resolution, we studied the susceptibility model performance by analyzing in detail the relevance of the conditioning variables. The analysis is based on landslide morphology data, considering either the whole landslide or only the source area outline as inputs. The procedure allowed us to select the most useful information, in terms of DEM spatial resolution, thematic variables and landslide inventory, in order to obtain the most reliable slope unit-based landslide susceptibility assessment.

  4. The Effectiveness of Problem Based Learning Integrated With Islamic Values Based on ICT on Higher Order Thinking Skill and Students’ Character

    Directory of Open Access Journals (Sweden)

    Chairul Anwar

    2017-02-01

    Full Text Available The focus of this research is to known the influence of Problem Based Learning (PBL model application, that intergrated with Islamic values based on ICT, toward the ability of higher-order thinkingskill and the strenghtening of students’ characters. This research is quasy experiment type with group design pretest-postest. The research was conducted in SMA.Sampling by means of random sampling, to determine the control class and experimentalclass.Data analysis technique used is the t-test, based on the value of significance, as well as test-effect size. The research data shows that the model of problem based learning integrates Islamic values based on ICThas positive influence towards the increasing of higher-order thinking skill and the strenghtening of students’ characters compared to the students that use conventional method.The result of effect size test on experimental class in on medium category. It means that the learning which use problem based learning (PBL model, integrated with Islamic values based on ICT, can be said effective on increasing higher order thinking skillof students.

  5. Services for prisoners with alcohol-related problems: a survey of U.K. prisons.

    Science.gov (United States)

    McMurran, M; Baldwin, S

    1989-09-01

    Offenders have been identified as heavy drinkers who admit to a relationship between drinking and offending. Many prisoners express a desire to reduce their alcohol consumption. The extent of alcohol interventions in U.K. prisons was unknown and so a postal survey was conducted to gather basic information about current work. Of all responding establishments, 91% claimed to provide services for prisoners with alcohol-related problems and 58% gave details of these services. Services are provided mainly by probation officers/social workers, prison officers and Alcoholics Anonymous. Group and individual interventions are described. Service development has been haphazard, lacking central co-ordination. A case is made for appointment of a central facilitator responsible for staff training, establishing a communications network, encouraging new interventions to match clients' needs, encouraging closer links with community workers and guiding evaluative research.

  6. 18F-fluorocholine PET-guided target volume delineation techniques for partial prostate re-irradiation in local recurrent prostate cancer

    International Nuclear Information System (INIS)

    Wang Hui; Vees, Hansjoerg; Miralbell, Raymond; Wissmeyer, Michael; Steiner, Charles; Ratib, Osman; Senthamizhchelvan, Srinivasan; Zaidi, Habib

    2009-01-01

    Background and purpose: We evaluate the contribution of 18 F-choline PET/CT in the delineation of gross tumour volume (GTV) in local recurrent prostate cancer after initial irradiation using various PET image segmentation techniques. Materials and methods: Seventeen patients with local-only recurrent prostate cancer (median = 5.7 years) after initial irradiation were included in the study. Rebiopsies were performed in 10 patients that confirmed the local recurrence. Following injection of 300 MBq of 18 F-fluorocholine, dynamic PET frames (3 min each) were reconstructed from the list-mode acquisition. Five PET image segmentation techniques were used to delineate the 18 F-choline-based GTVs. These included manual delineation of contours (GTV man ) by two teams consisting of a radiation oncologist and a nuclear medicine physician each, a fixed threshold of 40% and 50% of the maximum signal intensity (GTV 40% and GTV 50% ), signal-to-background ratio-based adaptive thresholding (GTV SBR ), and a region growing (GTV RG ) algorithm. Geographic mismatches between the GTVs were also assessed using overlap analysis. Results: Inter-observer variability for manual delineation of GTVs was high but not statistically significant (p = 0.459). In addition, the volumes and shapes of GTVs delineated using semi-automated techniques were significantly higher than those of GTVs defined manually. Conclusions: Semi-automated segmentation techniques for 18 F-choline PET-guided GTV delineation resulted in substantially higher GTVs compared to manual delineation and might replace the latter for determination of recurrent prostate cancer for partial prostate re-irradiation. The selection of the most appropriate segmentation algorithm still needs to be determined.

  7. 18F-fluorocholine PET-guided target volume delineation techniques for partial prostate re-irradiation in local recurrent prostate cancer.

    Science.gov (United States)

    Wang, Hui; Vees, Hansjörg; Miralbell, Raymond; Wissmeyer, Michael; Steiner, Charles; Ratib, Osman; Senthamizhchelvan, Srinivasan; Zaidi, Habib

    2009-11-01

    We evaluate the contribution of (18)F-choline PET/CT in the delineation of gross tumour volume (GTV) in local recurrent prostate cancer after initial irradiation using various PET image segmentation techniques. Seventeen patients with local-only recurrent prostate cancer (median=5.7 years) after initial irradiation were included in the study. Rebiopsies were performed in 10 patients that confirmed the local recurrence. Following injection of 300 MBq of (18)F-fluorocholine, dynamic PET frames (3 min each) were reconstructed from the list-mode acquisition. Five PET image segmentation techniques were used to delineate the (18)F-choline-based GTVs. These included manual delineation of contours (GTV(man)) by two teams consisting of a radiation oncologist and a nuclear medicine physician each, a fixed threshold of 40% and 50% of the maximum signal intensity (GTV(40%) and GTV(50%)), signal-to-background ratio-based adaptive thresholding (GTV(SBR)), and a region growing (GTV(RG)) algorithm. Geographic mismatches between the GTVs were also assessed using overlap analysis. Inter-observer variability for manual delineation of GTVs was high but not statistically significant (p=0.459). In addition, the volumes and shapes of GTVs delineated using semi-automated techniques were significantly higher than those of GTVs defined manually. Semi-automated segmentation techniques for (18)F-choline PET-guided GTV delineation resulted in substantially higher GTVs compared to manual delineation and might replace the latter for determination of recurrent prostate cancer for partial prostate re-irradiation. The selection of the most appropriate segmentation algorithm still needs to be determined.

  8. A One-Dimensional Thermoelastic Problem due to a Moving Heat Source under Fractional Order Theory of Thermoelasticity

    Directory of Open Access Journals (Sweden)

    Tianhu He

    2014-01-01

    Full Text Available The dynamic response of a one-dimensional problem for a thermoelastic rod with finite length is investigated in the context of the fractional order theory of thermoelasticity in the present work. The rod is fixed at both ends and subjected to a moving heat source. The fractional order thermoelastic coupled governing equations for the rod are formulated. Laplace transform as well as its numerical inversion is applied to solving the governing equations. The variations of the considered temperature, displacement, and stress in the rod are obtained and demonstrated graphically. The effects of time, velocity of the moving heat source, and fractional order parameter on the distributions of the considered variables are of concern and discussed in detail.

  9. Robust K-Median and K-Means Clustering Algorithms for Incomplete Data

    Directory of Open Access Journals (Sweden)

    Jinhua Li

    2016-01-01

    Full Text Available Incomplete data with missing feature values are prevalent in clustering problems. Traditional clustering methods first estimate the missing values by imputation and then apply the classical clustering algorithms for complete data, such as K-median and K-means. However, in practice, it is often hard to obtain accurate estimation of the missing values, which deteriorates the performance of clustering. To enhance the robustness of clustering algorithms, this paper represents the missing values by interval data and introduces the concept of robust cluster objective function. A minimax robust optimization (RO formulation is presented to provide clustering results, which are insensitive to estimation errors. To solve the proposed RO problem, we propose robust K-median and K-means clustering algorithms with low time and space complexity. Comparisons and analysis of experimental results on both artificially generated and real-world incomplete data sets validate the robustness and effectiveness of the proposed algorithms.

  10. Vessel based delineation guidelines for the elective lymph node regions in breast cancer radiation therapy – PROCAB guidelines

    International Nuclear Information System (INIS)

    Verhoeven, Karolien; Weltens, Caroline; Remouchamps, Vincent; Mahjoubi, Khalil; Veldeman, Liv; Lengele, Benoit; Hortobagyi, Eszter; Kirkove, Carine

    2015-01-01

    Objective: A national project to improve the quality of breast radiation therapy was started, named PROCAB (PROject on CAncer of the Breast). One of the objectives was to reach a national consensus guideline for the delineation of the regional lymph node areas in breast radiation therapy. Methods: The realization of the new guidelines was a step by step process that started with multiple expert meetings where the existing guidelines were analyzed and the delineations of the lymph node regions were performed together with a surgeon, specialized in the anatomy of the drainage of the breast. Results: The delineation guidelines are vessel-based. Since the occurrence of pathological lymph nodes is typically around the veins, the cranial and caudal borders of all different nodal regions are based on a 5 mm margin around the veins, except for the parasternal lymph node area. Compared to the existing guidelines there are some major changes. Conclusion: With this project a national as well as a European (ESTRO) consensus guideline for the delineation of the regional lymph node areas in breast RT is reached. The new delineation atlas is vessel-based and no longer field-based

  11. On vector equilibrium problem

    Indian Academy of Sciences (India)

    [G] Giannessi F, Theorems of alternative, quadratic programs and complementarity problems, in: Variational Inequalities and Complementarity Problems (eds) R W Cottle, F Giannessi and J L Lions (New York: Wiley) (1980) pp. 151±186. [K1] Kazmi K R, Existence of solutions for vector optimization, Appl. Math. Lett. 9 (1996).

  12. High-K isomers in {sup 176}W and mechanisms of K-violation

    Energy Technology Data Exchange (ETDEWEB)

    Crowell, B.; Janssens, R.V.F.; Blumenthal, D.J. [and others

    1995-08-01

    K-isomers are states in deformed nuclei whose {gamma}-decay is hindered by selection rules involving K, the projection of the angular momentum along the axis of symmetry of the nucleus. Previous work with the Argonne Notre Dame BGO Array delineated the existence of two K-isomers in {sup 176}W, one of which had a very unusual pattern of decay. A short description of this work was published as a letter, and a more complete account is being readied for submission. These results provided evidence that quantum-mechanical fluctuations in the nuclear shape may be responsible for some of the observed K-violating transitions. In addition, hints were present in the data of the existence of another K-isomer with an even higher in. An experiment was performed in September 1994 to observe this isomer, using the reaction {sup 50}Ti({sup 130}Te,4n), and a technique in which recoiling {sup 176}W nuclei were created 17-cm upstream of the center of the array and caught on a Pb catcher foil at the center. Intense ({approximately} 3 pnA) beams of {sup 130}Te were supplied by the ECR source using a new sputtering technique. The recoil-shadow geometry was highly successful at removing the background from non-isomeric decays, allowing the weakly populated K-isomers to be detected cleanly. In addition, the availability of pulsed beams from ATLAS and the timing data from the BGO array provided a second technique for isolating the decays of interest, by selecting events in which a given number of BGO detectors fired between beam pulses. This method was used in the previous experiment, and was also applied in this experiment as a second level of selection. As a result, gamma-ray transitions were detected in the present experiment with intensities as small as {approximately} 0.02 % of the {sup 176}W reaction channel. The existence of the new isomer was confirmed, and a partial level-scheme was constructed.

  13. Solving math and science problems in the real world with a computational mind

    Directory of Open Access Journals (Sweden)

    Juan Carlos Olabe

    2014-07-01

    Full Text Available This article presents a new paradigm for the study of Math and Sciences curriculum during primary and secondary education. A workshop for Education undergraduates at four different campuses (n=242 was designed to introduce participants to the new paradigm. In order to make a qualitative analysis of the current school methodologies in mathematics, participants were introduced to a taxonomic tool for the description of K-12 Math problems. The tool allows the identification, decomposition and description of Type-A problems, the characteristic ones in the traditional curriculum, and of Type-B problems in the new paradigm. The workshops culminated with a set of surveys where participants were asked to assess both the current and the new proposed paradigms. The surveys in this study revealed that according to the majority of participants: (i The K-12 Mathematics curricula are designed to teach students exclusively the resolution of Type-A problems; (ii real life Math problems respond to a paradigm of Type-B problems; and (iii the current Math curriculum should be modified to include this new paradigm.

  14. Optical system for object detection and delineation in space

    Science.gov (United States)

    Handelman, Amir; Shwartz, Shoam; Donitza, Liad; Chaplanov, Loran

    2018-01-01

    Object recognition and delineation is an important task in many environments, such as in crime scenes and operating rooms. Marking evidence or surgical tools and attracting the attention of the surrounding staff to the marked objects can affect people's lives. We present an optical system comprising a camera, computer, and small laser projector that can detect and delineate objects in the environment. To prove the optical system's concept, we show that it can operate in a hypothetical crime scene in which a pistol is present and automatically recognize and segment it by various computer-vision algorithms. Based on such segmentation, the laser projector illuminates the actual boundaries of the pistol and thus allows the persons in the scene to comfortably locate and measure the pistol without holding any intermediator device, such as an augmented reality handheld device, glasses, or screens. Using additional optical devices, such as diffraction grating and a cylinder lens, the pistol size can be estimated. The exact location of the pistol in space remains static, even after its removal. Our optical system can be fixed or dynamically moved, making it suitable for various applications that require marking of objects in space.

  15. The Regionalization of Africa: Delineating Africa's Subregions Using Airline Data

    Science.gov (United States)

    Good, Pieter R.; Derudder, Ben; Witlox, Frank J.

    2011-01-01

    Current regionalizations of Africa have limitations in that they are attribute-based and regions are delineated according to national boundaries. Taking the world city network approach as starting point, it is possible to use relational data (i.e., information about the relationships between cities) rather than attribute data, and moreover, it…

  16. Factorization of Constrained Energy K-Network Reliability with Perfect Nodes

    OpenAIRE

    Burgos, Juan Manuel

    2013-01-01

    This paper proves a new general K-network constrained energy reliability global factorization theorem. As in the unconstrained case, beside its theoretical mathematical importance the theorem shows how to do parallel processing in exact network constrained energy reliability calculations in order to reduce the processing time of this NP-hard problem. Followed by a new simple factorization formula for its calculation, we propose a new definition of constrained energy network reliability motiva...

  17. Variations Method to Solve Terminal Problems for the Second Order Systems of Canonical Form with State Constraints

    Directory of Open Access Journals (Sweden)

    T. S. Kasatkina

    2015-01-01

    Full Text Available Terminal control problem with fixed finite time for the second order affine systems with state constraints is considered. A solution of such terminal problem is suggested for the systems with scalar control of regular canonical form.In this article it is shown that the initial terminal problem is equivalent to the problem of auxiliary function search. This function should satisfy some conditions. Such function design consists of two stages. The first stage includes search of function which corresponds the solution of the terminal control problem without state constraints. This function is designed as polynom of the fifth power which depends on time variable. Coefficients of the polynom are defined by boundary conditions. The second stage includes modification of designed function if corresponding to that function trajectory is not satisfied constraints. Modification process is realized by adding to the current function supplementary polynom. Influence of that polynom handles by variation of a parameter value. Modification process can include a few iterations. After process termination continuous control is found. This control is the solution of the initial terminal prUsing presented scheme the terminal control problem for system, which describes oscillations of the mathematical pendulum, is solved. This approach can be used for the solution of terminal control problems with state constraints for affine systems with multi-dimensional control.

  18. High-Order Analytic Expansion of Disturbing Function for Doubly Averaged Circular Restricted Three-Body Problem

    Directory of Open Access Journals (Sweden)

    Takashi Ito

    2016-01-01

    Full Text Available Terms in the analytic expansion of the doubly averaged disturbing function for the circular restricted three-body problem using the Legendre polynomial are explicitly calculated up to the fourteenth order of semimajor axis ratio (α between perturbed and perturbing bodies in the inner case (α1. The expansion outcome is compared with results from numerical quadrature on an equipotential surface. Comparison with direct numerical integration of equations of motion is also presented. Overall, the high-order analytic expansion of the doubly averaged disturbing function yields a result that agrees well with the numerical quadrature and with the numerical integration. Local extremums of the doubly averaged disturbing function are quantitatively reproduced by the high-order analytic expansion even when α is large. Although the analytic expansion is not applicable in some circumstances such as when orbits of perturbed and perturbing bodies cross or when strong mean motion resonance is at work, our expansion result will be useful for analytically understanding the long-term dynamical behavior of perturbed bodies in circular restricted three-body systems.

  19. Warehouse Order-Picking Process. Review

    Directory of Open Access Journals (Sweden)

    E. V. Korobkov

    2015-01-01

    Full Text Available This article describes basic warehousing activities, namely: movement, information storage and transfer, as well as connections between typical warehouse operations (reception, transfer, assigning storage position and put-away, order-picking, hoarding and sorting, cross-docking, shipping. It presents a classification of the warehouse order-picking systems in terms of manual labor on offer as well as external (marketing channels, consumer’s demand structure, supplier’s replenishment structure and inventory level, total production demand, economic situation and internal (mechanization level, information accessibility, warehouse dimensionality, method of dispatch for shipping, zoning, batching, storage assignment method, routing method factors affecting the designing systems complexity. Basic optimization considerations are described. There is a literature review on the following sub-problems of planning and control of orderpicking processes.A layout design problem has been taken in account at two levels — external (facility layout problem and internal (aisle configuration problem. For a problem of distributing goods or stock keeping units the following methods are emphasized: random, nearest open storage position, and dedicated (COI-based, frequency-based distribution, as well as class-based and familygrouped (complimentary- and contact-based one. Batching problem can be solved by two main methods, i.e. proximity order batching (seed and saving algorithms and time-window order batching. There are two strategies for a zoning problem: progressive and synchronized, and also a special case of zoning — bucket brigades method. Hoarding/sorting problem is briefly reviewed. Order-picking routing problem will be thoroughly described in the next article of the cycle “Warehouse order-picking process”.

  20. Benchmark of Client and Server-Side Catchment Delineation Approaches on Web-Based Systems

    Science.gov (United States)

    Demir, I.; Sermet, M. Y.; Sit, M. A.

    2016-12-01

    Recent advances in internet and cyberinfrastructure technologies have provided the capability to acquire large scale spatial data from various gauges and sensor networks. The collection of environmental data increased demand for applications which are capable of managing and processing large-scale and high-resolution data sets. With the amount and resolution of data sets provided, one of the challenging tasks for organizing and customizing hydrological data sets is delineation of watersheds on demand. Watershed delineation is a process for creating a boundary that represents the contributing area for a specific control point or water outlet, with intent of characterization and analysis of portions of a study area. Although many GIS tools and software for watershed analysis are available on desktop systems, there is a need for web-based and client-side techniques for creating a dynamic and interactive environment for exploring hydrological data. In this project, we demonstrated several watershed delineation techniques on the web with various techniques implemented on the client-side using JavaScript and WebGL, and on the server-side using Python and C++. We also developed a client-side GPGPU (General Purpose Graphical Processing Unit) algorithm to analyze high-resolution terrain data for watershed delineation which allows parallelization using GPU. The web-based real-time analysis of watershed segmentation can be helpful for decision-makers and interested stakeholders while eliminating the need of installing complex software packages and dealing with large-scale data sets. Utilization of the client-side hardware resources also eliminates the need of servers due its crowdsourcing nature. Our goal for future work is to improve other hydrologic analysis methods such as rain flow tracking by adapting presented approaches.

  1. Engineering the path to higher-order thinking in elementary education: A problem-based learning approach for STEM integration

    Science.gov (United States)

    Rehmat, Abeera Parvaiz

    As we progress into the 21st century, higher-order thinking skills and achievement in science and math are essential to meet the educational requirement of STEM careers. Educators need to think of innovative ways to engage and prepare students for current and future challenges while cultivating an interest among students in STEM disciplines. An instructional pedagogy that can capture students' attention, support interdisciplinary STEM practices, and foster higher-order thinking skills is problem-based learning. Problem-based learning embedded in the social constructivist view of teaching and learning (Savery & Duffy, 1995) promotes self-regulated learning that is enhanced through exploration, cooperative social activity, and discourse (Fosnot, 1996). This quasi-experimental mixed methods study was conducted with 98 fourth grade students. The study utilized STEM content assessments, a standardized critical thinking test, STEM attitude survey, PBL questionnaire, and field notes from classroom observations to investigate the impact of problem-based learning on students' content knowledge, critical thinking, and their attitude towards STEM. Subsequently, it explored students' experiences of STEM integration in a PBL environment. The quantitative results revealed a significant difference between groups in regards to their content knowledge, critical thinking skills, and STEM attitude. From the qualitative results, three themes emerged: learning approaches, increased interaction, and design and engineering implementation. From the overall data set, students described the PBL environment to be highly interactive that prompted them to employ multiple approaches, including design and engineering to solve the problem.

  2. The study of target delineation and target movement of whole breast assisted by active breathing control in intensity modulated radiotherapy after breast conservative surgery

    International Nuclear Information System (INIS)

    Li Jianbing; Yu Jinming; Ma Zhifang; Lu Jie; Sun Tao; Guo Shoufang; Wang Jingguo

    2009-01-01

    Objective: To explore the influence of different delineators and different delineating time on target determination of the whole breast and to explore intrafraction and interfraction target displacements of the breast on moderate deep inspiration breathing hold (mDIBH) assisted by active breathing control (ABC) alter breast conservative surgery. Methods: Twenty patients received primary CT-simulation assisted by ABC to get five sets of CT image on the three breathing condition which included one set from free breath (FB), two sets from mDIBH and two sets from deep expiration breathing control (DEBH). After radiotherapy with ten to fifteen fractions, the repeat CT-simulation was carried out to get the same five sets of CT image as the primary CT- simulation. The whole breast target were delineated at different time by the same delineator and delineated respectively by five delineators on the first set of CT images got with mDIBH from the primary CT-simulation, and to compare the influence of delineator and delineating time on the whole breast target. The total silver clips in the cavity were marked respectively on the two sets of CT images got with mDIBH from the primary CT-simulation, and to compare the intrafraction displacement of geometric body structured by the total of silver clips. The two ribs near the isocentric plane of the breast target were delineated respectively on two sets of the mDIBH CT image from the primary CT-simulation and on one set of the mDIBH CT image from the repeat CT-simulation, and comparing the movement of the point of interest (POI) of the ribs delineated to get the value of intrafraction and interfraction thoracic expansion. Results: There was not statistically significant between the four volumes of whole breast targets delineated by the same delineator at different time, but with statistics significant between the volumes of whole breast target delineated by the different delineators ( F=19.681, P=0.000). There was not statistically

  3. A HIGH ORDER SOLUTION OF THREE DIMENSIONAL TIME DEPENDENT NONLINEAR CONVECTIVE-DIFFUSIVE PROBLEM USING MODIFIED VARIATIONAL ITERATION METHOD

    Directory of Open Access Journals (Sweden)

    Pratibha Joshi

    2014-12-01

    Full Text Available In this paper, we have achieved high order solution of a three dimensional nonlinear diffusive-convective problem using modified variational iteration method. The efficiency of this approach has been shown by solving two examples. All computational work has been performed in MATHEMATICA.

  4. French 400 kV network

    Energy Technology Data Exchange (ETDEWEB)

    Pelissier, R

    1965-11-01

    A 400 kV transmission network has been constructed to carry hydroelectric power from the Alps and the Massif Central to Paris at peak hours and to carry power in the reverse direction in off-peak hours. A double circuit-ring at 400 kV encircling the Paris region is also nearing completion. Measures have to be taken to counter the very high short-circuit currents in such a network. A 730 kV network will eventually become necessary. The consequent multiplicity of transmission voltages will give rise to further problems. Collaboration with neighboring countries is envisaged. The problems of stability and synchronization posed by the new system are described and solutions suggested. The new circuit-breaking requirements are discussed, and details of tower design for 400 kV and 730 kV are given.

  5. The Psychometrics of the Mini-K.

    Science.gov (United States)

    Richardson, George B; Chen, Ching-Chen; Dai, Chia-Liang; Brubaker, Michael D; Nedelec, Joseph L

    2017-01-01

    Many published studies have employed the Mini-K to measure a single fast-slow life history dimension. However, the internal structure of the Mini-K has not been determined and it is not clear that a single higher order K-factor fits the data. It is also not clear that the Mini-K is measurement invariant across groups such as the sexes. To establish the construct validity of K as well as the broader usefulness of applying life history theory to humans, it is crucial that these psychometric issues are addressed as a part of measure validation efforts. Here we report on three studies that used latent variable modeling and data drawn from two college student samples ( ns = 361 and 300) to elucidate the psychometrics of the Mini-K. We found that (a) the Mini-K had a six dimensional first-order structure, (b) the K-factor provided a parsimonious explanation of the associations among the lower order factors at no significant cost to fit, (c) the Mini-K measured the same K-factor across the sexes, (d) K-factor means did not have the same meaning across the sexes and thus the first-order factors should be used in studies of mean sex differences, and finally, (e) the K-factor was only associated with environment and aspects of mating competition in females. Implications and future directions for life history research are discussed.

  6. The global kernel k-means algorithm for clustering in feature space.

    Science.gov (United States)

    Tzortzis, Grigorios F; Likas, Aristidis C

    2009-07-01

    Kernel k-means is an extension of the standard k -means clustering algorithm that identifies nonlinearly separable clusters. In order to overcome the cluster initialization problem associated with this method, we propose the global kernel k-means algorithm, a deterministic and incremental approach to kernel-based clustering. Our method adds one cluster at each stage, through a global search procedure consisting of several executions of kernel k-means from suitable initializations. This algorithm does not depend on cluster initialization, identifies nonlinearly separable clusters, and, due to its incremental nature and search procedure, locates near-optimal solutions avoiding poor local minima. Furthermore, two modifications are developed to reduce the computational cost that do not significantly affect the solution quality. The proposed methods are extended to handle weighted data points, which enables their application to graph partitioning. We experiment with several data sets and the proposed approach compares favorably to kernel k -means with random restarts.

  7. Assessment of various strategies for 18F-FET PET-guided delineation of target volumes in high-grade glioma patients

    International Nuclear Information System (INIS)

    Vees, Hansjoerg; Senthamizhchelvan, Srinivasan; Ratib, Osman; Miralbell, Raymond; Weber, Damien C.; Zaidi, Habib

    2009-01-01

    The purpose of the study is to assess the contribution of 18 F-fluoro-ethyl-tyrosine ( 18 F-FET) positron emission tomography (PET) in the delineation of gross tumor volume (GTV) in patients with high-grade gliomas compared with magnetic resonance imaging (MRI) alone. The study population consisted of 18 patients with high-grade gliomas. Seven image segmentation techniques were used to delineate 18 F-FET PET GTVs, and the results were compared to the manual MRI-derived GTV (GTV MRI ). PET image segmentation techniques included manual delineation of contours (GTV man ), a 2.5 standardized uptake value (SUV) cutoff (GTV 2.5 ), a fixed threshold of 40% and 50% of the maximum signal intensity (GTV 40% and GTV 50% ), signal-to-background ratio (SBR)-based adaptive thresholding (GTV SBR ), gradient find (GTV GF ), and region growing (GTV RG ). Overlap analysis was also conducted to assess geographic mismatch between the GTVs delineated using the different techniques. Contours defined using GTV 2.5 failed to provide successful delineation technically in three patients (18% of cases) as SUV max MRI (67% of cases). Yet, PET detected frequently tumors that are not visible on MRI and added substantially tumor extension outside the GTV MRI in six patients (33% of cases). The selection of the most appropriate 18 F-FET PET-based segmentation algorithm is crucial, since it impacts both the volume and shape of the resulting GTV. The 2.5 SUV isocontour and GF segmentation techniques performed poorly and should not be used for GTV delineation. With adequate setting, the SBR-based PET technique may add considerably to conventional MRI-guided GTV delineation. (orig.)

  8. Cascade calculation of K--p and K--d atoms

    International Nuclear Information System (INIS)

    Koike, T.; Harada, T.; Akaishi, Y.

    1995-09-01

    X-ray yields of K - -p and K - -d atoms are calculated as a function of the target density in order to find an optimum condition for experiments. The dependence of the yields on the energy level shift and absorption width due to the strong interaction is systematically investigated. (author)

  9. Inter-observer delineation uncertainty in radiotherapy of peripheral lung tumours

    DEFF Research Database (Denmark)

    Persson, Gitte Fredberg; Nygaard, Ditte Eklund; Roed, Anders Peter

    was included in the study. In our clinical protocol the contrast enhanced PET/CT scan is primarily analysed by a specialist in nuclear medicine and a radiologists together. The PET positive volume is delineated by the specialist in nuclear medicine and only the CT scan and this contour is imported to Eclipse...

  10. Mind over matter? I: philosophical aspects of the mind-brain problem.

    Science.gov (United States)

    Schimmel, P

    2001-08-01

    To conceptualize the essence of the mind-body or mind-brain problem as one of metaphysics rather than science, and to propose a formulation of the problem in the context of current scientific knowledge and its limitations. The background and conceptual parameters of the mind-body problem are delineated, and the limitations of brain research in formulating a solution identified. The problem is reformulated and stated in terms of two propositions. These constitute a 'double aspect theory'. The problem appears to arise as a consequence of the conceptual limitations of the human mind, and hence remains essentially a metaphysical one. A 'double aspect theory' recognizes the essential unity of mind and brain, while remaining consistent with the dualism inherent in human experience.

  11. Existence of Positive Solutions for a Coupled System of (p, q-Laplacian Fractional Higher Order Boundary Value Problems

    Directory of Open Access Journals (Sweden)

    K.R. Prasad

    2015-11-01

    Full Text Available In this paper, we establish the existence of at least three positive solutions for a system of (p,q-Laplacian fractional order two-point boundary value problems by applying five functionals fixed point theorem under suitable conditions on a cone in a Banach space.

  12. Variability in prostate and seminal vesicle delineations defined on magnetic resonance images, a multi-observer, -center and -sequence study

    DEFF Research Database (Denmark)

    Nyholm, Tufve; Jonsson, Joakim; Söderström, Karin

    2013-01-01

    and approximately equal for the prostate and seminal vesicles. Large differences in variability were observed for individual patients, and also for individual imaging sequences used at the different centers. There was however no indication of decreased variability with higher field strength. CONCLUSION: The overall......BACKGROUND: The use of magnetic resonance (MR) imaging as a part of preparation for radiotherapy is increasing. For delineation of the prostate several publications have shown decreased delineation variability using MR compared to computed tomography (CT). The purpose of the present work....... Two physicians from each center delineated the prostate and the seminal vesicles on each of the 25 image sets. The variability between the delineations was analyzed with respect to overall, intra- and inter-physician variability, and dependence between variability and origin of the MR images, i...

  13. Inequalities for the Modified k-Bessel Function

    Directory of Open Access Journals (Sweden)

    Saiful Rahman Mondal

    2017-07-01

    Full Text Available The article considers the generalized k-Bessel functions and represents it as Wright functions. Then we study the monotonicity properties of the ratio of two different orders k- Bessel functions, and the ratio of the k-Bessel and the k-Bessel functions. The log-convexity with respect to the order of the k-Bessel also given. An investigation regarding the monotonicity of the ratio of the k-Bessel and k-confluent hypergeometric functions are discussed.

  14. Cleanup Verification Package for the 100-K-55:1 and 100-K-56:1 Pipelines and the 116-KW-4 and 116-KE-5 Heat Recovery Stations

    International Nuclear Information System (INIS)

    Capron, J.M.

    2005-01-01

    This cleanup verification package documents completion of remedial action for the 100-K-55:1 and 100-K-56:1 reactor cooling effluent underground pipelines and for the 116-KW-4 and 116-KE-5 heat recovery stations. The 100-K-55 and 100-K-56 sites consisted of those process effluent pipelines that serviced the 105-KW and 105-KE Reactors. This cleanup verification package documents completion of remedial action for the 100-K-55: 1 and 100-K-56: 1 reactor cooling effluent underground pipelines, referred to herein as the 100-K-55:1 and 100-K-56:l sites, as well as for the 116-KW-4 and 116-KE-5 heat recovery stations, referred to herein as the 116-KW-4 and 116-KE-5 sites. The 116-KW-4 and 116-KE-5 heat recovery stations were co-located and remediated with the 100-K-55:1 and 100-K-56:1 pipelines, respectively. These sites are located in the 100-KR-2 Operable Unit in the 100-K Area of the Hanford Site in southeastern Washington State. The 100-K-55 and 100-K-56 sites consisted of those process effluent pipelines that serviced the 105-KW and 105-KE Reactors, respectively. Both of these sites have been administratively divided into subunits based on the current extent of remediation. Portions of the pipelines remaining within the reactor security fencing and in proximity to active utility features have been delineated as the 100-K-55:2 and 100-K-56:2 pipelines, with the portions of the pipelines excluded from these boundaries identified as the 100-K-55:1 and 100-K-56:1 pipelines. This cleanup verification package addresses only the 100-K-55:1 and 100-K-56:I subunits; the 100-K-55:2 and 100-K-56:2 subunits will be addressed within a separate cleanup verification package. Site excavation and waste disposal are complete, and the exposed surfaces have been sampled and analyzed to verify attainment of the remedial action goals. Results of the sampling, laboratory analyses, and data evaluations for the 100-K-55:1, 100-K-56:1, 116-KW-4, and 116-KE-5 sites indicate that all remedial

  15. Combined reflectance confocal microscopy-optical coherence tomography for delineation of basal cell carcinoma margins: an ex vivo study

    Science.gov (United States)

    Iftimia, Nicusor; Peterson, Gary; Chang, Ernest W.; Maguluri, Gopi; Fox, William; Rajadhyaksha, Milind

    2016-01-01

    We present a combined reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) approach, integrated within a single optical layout, for diagnosis of basal cell carcinomas (BCCs) and delineation of margins. While RCM imaging detects BCC presence (diagnoses) and its lateral spreading (margins) with measured resolution of ˜1 μm, OCT imaging delineates BCC depth spreading (margins) with resolution of ˜7 μm. When delineating margins in 20 specimens of superficial and nodular BCCs, depth could be reliably determined down to ˜600 μm, and agreement with histology was within about ±50 μm.

  16. Structural studies of some bacterial capsular polysaccharides from the family enterobacteriaceae: Klebsiella serotypes K79 and K35 and Escherichia coli serotype K44

    Energy Technology Data Exchange (ETDEWEB)

    Lim, A.V.S.

    1986-01-01

    The techniques of sugar analysis, methylation, chromic acid oxidation, deamination, base-catalyzed uronic acid degradation, Smith degradation and partial hydrolysis were used in the structural elucidation of bacterial capsular polysaccharides. Methods such as gas-liquid chromatography, gas chromatography-mass spectrometry, gel permeation, ion-exchange and paper-chromatography were used to isolate and characterize oligosaccharides obtained from degradative procedures. N.m.r. spectroscopy (/sup 1/H and /sup 13/C) was widely used in the characterization of the polysaccharides and of derived poly- and oligo-saccharides. In a few instances, n.m.r. spectroscopy and mass spectrometry were used to delineate the sequence of the sugars in the structure of the poly- and oligo-saccharides. The bacteriophage-induced depolymerizations of the capsular polysaccharides of Klebsiella K79 and E. coli K44 are also reported in this thesis. The sum of these experiments demonstrated that the endoglycanase associated with Klebsiella Phi 79 had ..beta..-galactosidase activity. The endoglycanase from E. coli Phi 44 exhibited ..beta..-N-acetyl-galactosaminidase activity which is novel, in that it is the first reported action of this nature in the bacteriophages isolated for the species E. coli.

  17. Problems in the K-Ar dating of Quaternary volcanic rocks younger than 1 Ma

    International Nuclear Information System (INIS)

    Takaoka, Nobuo

    1989-01-01

    The assumption that the 40 Ar/ 36 Ar ratio of Ar trapped in volcanic rocks at eruption is atmospheric often gives a large systematic error in the K-Ar dating of Quaternary volcanic rocks younger than 1 Ma. There are two possible sources of error, the existence of excess Ar and mass-fractionated, initial Ar. The major source of excess Ar is supposed to be magma. The 40 Ar/ 36 Ar ratio for magmatic Ar in the North-East Japan arc is tentatively estimated to be 340±10 from measurements of Ar in large phenocrysts separated from Quaternary volcanic rocks. Separation of phenocrysts is the most effective to decrease the systematic error caused by excess Ar. The mass-fractionation of initial Ar should give the 38 Ar/ 36 Ar ratio which was changed from the atmospheric ratio. This can be checked by determining the 38 Ar/ 36 Ar ratio in samples. Since the systematic error caused by the mass-fractionated, initial Ar increases greatly with the increasing atmospheric Ar correction, it is important to correct the result for the mass-fractionation. Correction formulae are given. The error sources other than those mentioned above are uncertainty in the blank correction and instabilities in the sensitivity of spectrometer and the Ar isotopic ratio measurement. In order to increase accuracy of the K-Ar age obtained, to check the systematic errors by measuring samples together with standard samples is of great importance in the K-Ar dating of very young volcanic rocks. (author)

  18. Multiple-correction hybrid k-exact schemes for high-order compressible RANS-LES simulations on fully unstructured grids

    Science.gov (United States)

    Pont, Grégoire; Brenner, Pierre; Cinnella, Paola; Maugars, Bruno; Robinet, Jean-Christophe

    2017-12-01

    A Godunov's type unstructured finite volume method suitable for highly compressible turbulent scale-resolving simulations around complex geometries is constructed by using a successive correction technique. First, a family of k-exact Godunov schemes is developed by recursively correcting the truncation error of the piecewise polynomial representation of the primitive variables. The keystone of the proposed approach is a quasi-Green gradient operator which ensures consistency on general meshes. In addition, a high-order single-point quadrature formula, based on high-order approximations of the successive derivatives of the solution, is developed for flux integration along cell faces. The proposed family of schemes is compact in the algorithmic sense, since it only involves communications between direct neighbors of the mesh cells. The numerical properties of the schemes up to fifth-order are investigated, with focus on their resolvability in terms of number of mesh points required to resolve a given wavelength accurately. Afterwards, in the aim of achieving the best possible trade-off between accuracy, computational cost and robustness in view of industrial flow computations, we focus more specifically on the third-order accurate scheme of the family, and modify locally its numerical flux in order to reduce the amount of numerical dissipation in vortex-dominated regions. This is achieved by switching from the upwind scheme, mostly applied in highly compressible regions, to a fourth-order centered one in vortex-dominated regions. An analytical switch function based on the local grid Reynolds number is adopted in order to warrant numerical stability of the recentering process. Numerical applications demonstrate the accuracy and robustness of the proposed methodology for compressible scale-resolving computations. In particular, supersonic RANS/LES computations of the flow over a cavity are presented to show the capability of the scheme to predict flows with shocks

  19. Effects of data resolution and stream delineation threshold area on ...

    African Journals Online (AJOL)

    The results also indicate that peak flow and slope of the hydrograph rising limb obtained from the SRTM DEM at different threshold areas (ranging from 0.25% to 3%) are greater than that for the TOPO DEM. Investigating the effects of stream network delineation threshold area on the simulated peak flow shows that the ...

  20. Basic problems solving for two-dimensional discrete 3 × 4 order hidden markov model

    International Nuclear Information System (INIS)

    Wang, Guo-gang; Gan, Zong-liang; Tang, Gui-jin; Cui, Zi-guan; Zhu, Xiu-chang

    2016-01-01

    A novel model is proposed to overcome the shortages of the classical hypothesis of the two-dimensional discrete hidden Markov model. In the proposed model, the state transition probability depends on not only immediate horizontal and vertical states but also on immediate diagonal state, and the observation symbol probability depends on not only current state but also on immediate horizontal, vertical and diagonal states. This paper defines the structure of the model, and studies the three basic problems of the model, including probability calculation, path backtracking and parameters estimation. By exploiting the idea that the sequences of states on rows or columns of the model can be seen as states of a one-dimensional discrete 1 × 2 order hidden Markov model, several algorithms solving the three questions are theoretically derived. Simulation results further demonstrate the performance of the algorithms. Compared with the two-dimensional discrete hidden Markov model, there are more statistical characteristics in the structure of the proposed model, therefore the proposed model theoretically can more accurately describe some practical problems.

  1. Sampling problems for randomly broken sticks

    Energy Technology Data Exchange (ETDEWEB)

    Huillet, Thierry [Laboratoire de Physique Theorique et Modelisation, CNRS-UMR 8089 et Universite de Cergy-Pontoise, 5 mail Gay-Lussac, 95031, Neuville sur Oise (France)

    2003-04-11

    Consider the random partitioning model of a population (represented by a stick of length 1) into n species (fragments) with identically distributed random weights (sizes). Upon ranking the fragments' weights according to ascending sizes, let S{sub m:n} be the size of the mth smallest fragment. Assume that some observer is sampling such populations as follows: drop at random k points (the sample size) onto this stick and record the corresponding numbers of visited fragments. We shall investigate the following sampling problems: (1) what is the sample size if the sampling is carried out until the first visit of the smallest fragment (size S{sub 1:n})? (2) For a given sample size, have all the fragments of the stick been visited at least once or not? This question is related to Feller's random coupon collector problem. (3) In what order are new fragments being discovered and what is the random number of samples separating the discovery of consecutive new fragments until exhaustion of the list? For this problem, the distribution of the size-biased permutation of the species' weights, as the sequence of their weights in their order of appearance is needed and studied.

  2. Second-Order Science of Interdisciplinary Research

    DEFF Research Database (Denmark)

    Alrøe, Hugo Fjelsted; Noe, Egon

    2014-01-01

    require and challenge interdisciplinarity. Problem: The conventional methods of interdisciplinary research fall short in the case of wicked problems because they remain first-order science. Our aim is to present workable methods and research designs for doing second-order science in domains where...... there are many different scientific knowledges on any complex problem. Method: We synthesize and elaborate a framework for second-order science in interdisciplinary research based on a number of earlier publications, experiences from large interdisciplinary research projects, and a perspectivist theory...... of science. Results: The second-order polyocular framework for interdisciplinary research is characterized by five principles. Second-order science of interdisciplinary research must: 1. draw on the observations of first-order perspectives, 2. address a shared dynamical object, 3. establish a shared problem...

  3. Nuclear magnetic ordering in PrNi5

    International Nuclear Information System (INIS)

    Kubota, M.

    1980-11-01

    The specific heat of the hyperfine enhanced nuclear magnetic system PrNi 5 has been measured from 0.2 mK to 100 mK and in magnetic fields up to 6 T. The system was found to order at (0.40+-0.02) mK. From the study of the measured thermodynamic quantities in various magnetic fields, we obtain various information, the order at T=0 K is ferromagnetic, the hyperfine enhancement factor 1+K=(12.2+-0.5), the enhanced nuclear magnetic moment is (0.027+-0.004)μsub(B) and a nuclear exchange parameter μsub(j)Ksup(N)sub(ij)/ksub(B)=(0.20+-0.04) mK. The nature of the interactions which cause the ordering is discussed, together with the magnetic properties of the system deduced from the analysis. (orig.)

  4. Atlas-based delineation of lymph node levels in head and neck computed tomography images

    International Nuclear Information System (INIS)

    Commowick, Olivier; Gregoire, Vincent; Malandain, Gregoire

    2008-01-01

    Purpose: Radiotherapy planning requires accurate delineations of the tumor and of the critical structures. Atlas-based segmentation has been shown to be very efficient to automatically delineate brain critical structures. We therefore propose to construct an anatomical atlas of the head and neck region. Methods and materials: Due to the high anatomical variability of this region, an atlas built from a single image as for the brain is not adequate. We address this issue by building a symmetric atlas from a database of manually segmented images. First, we develop an atlas construction method and apply it to a database of 45 Computed Tomography (CT) images from patients with node-negative pharyngo-laryngeal squamous cell carcinoma manually delineated for radiotherapy. Then, we qualitatively and quantitatively evaluate the results generated by the built atlas based on Leave-One-Out framework on the database. Results: We present qualitative and quantitative results using this atlas construction method. The evaluation was performed on a subset of 12 patients among the original CT database of 45 patients. Qualitative results depict visually well delineated structures. The quantitative results are also good, with an error with respect to the best achievable results ranging from 0.196 to 0.404 with a mean of 0.253. Conclusions: These results show the feasibility of using such an atlas for radiotherapy planning. Many perspectives are raised from this work ranging from extensive validation to the construction of several atlases representing sub-populations, to account for large inter-patient variabilities, and populations with node-positive tumors

  5. Imaging of odor perception delineates functional disintegration of the limbic circuits in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Ciumas, Carolina; Lindström, Per; Aoun, Bernard; Savic, Ivanka

    2008-01-15

    Metabolic and neuro-receptor abnormalities within the extrafocal limbic circuits are established in mesial temporal lobe epilepsy (MTLE). However, very little is known about how these circuits process external stimuli. We tested whether odor activation can help delineate limbic functional disintegration in MTLE, and measured cerebral blood flow with PET during birhinal smelling of familiar and unfamiliar odors, using smelling of odorless air as the baseline condition. Patients with MTLE (13 left-sided, 10 right-sided) and 21 controls were investigated. In addition to odor activation, the analysis included functional connectivity, using right and left piriform cortex as seed regions. Healthy controls activated the amygdala, piriform, anterior insular, and cingulate cortices on both sides. Smelling of familiar odors engaged, in addition, the right parahippocampus, and the left Brodmann Area (BA) 44, 45, 47. Patients failed to activate the amygdala, piriform and the anterior insular cortex in the epileptogenic hemisphere. Furthermore, those with left MTLE did not activate the left BA 44, 45 and 47 with familiar odors, which they perceived as less familiar than controls. Congruent with the activation data each seed region was in patients functionally disconnected with the contralateral amygdala+piriform+insular cortex. The functional disintegration in patients exceeded the reduced activation, and included the contralateral temporal neocortex, and in subjects with right MTLE also the right orbitofrontal cortex. Imaging of odor perception may be used to delineate functional disintegration of the limbic networks in MTLE. It shows an altered response in several regions, which may underlie some interictal behavioral problems associated with this condition.

  6. A Trigonometrically Fitted Block Method for Solving Oscillatory Second-Order Initial Value Problems and Hamiltonian Systems

    OpenAIRE

    Ngwane, F. F.; Jator, S. N.

    2017-01-01

    In this paper, we present a block hybrid trigonometrically fitted Runge-Kutta-Nyström method (BHTRKNM), whose coefficients are functions of the frequency and the step-size for directly solving general second-order initial value problems (IVPs), including Hamiltonian systems such as the energy conserving equations and systems arising from the semidiscretization of partial differential equations (PDEs). Four discrete hybrid formulas used to formulate the BHTRKNM are provided by a continuous one...

  7. Almost all k-cop-win graphs contain a dominating set of cardinality k

    OpenAIRE

    Pralat, Pawel

    2013-01-01

    We consider $k$-cop-win graphs in the binomial random graph $G(n,1/2).$ It is known that almost all cop-win graphs contain a universal vertex. We generalize this result and prove that for every $k \\in N$, almost all $k$-cop-win graphs contain a dominating set of cardinality $k$. From this it follows that the asymptotic number of labelled $k$-cop-win graphs of order $n$ is equal to $(1+o(1)) (1-2^{-k})^{-k} {n \\choose k} 2^{n^2/2 - (1/2-\\log_2(1-2^{-k})) n}$.

  8. Riparian ecotone: A functional definition and delineation for resource assessment

    Science.gov (United States)

    E. S Verry; C. A Dolloff; M. E. Manning

    2004-01-01

    We propose a geomorphic basis for defining riparian areas using the term: riparian ecotone, discuss how past definitions fall short, and illustrate how a linked sequence of definition, delineation, and riparian sampling are used to accurately assess riparian resources on the ground. Our riparian ecotone is based on the width of the valley (its floodprone area width)...

  9. Dark energy and bouncing universe from k-fields

    International Nuclear Information System (INIS)

    Kang, Jin U

    2009-01-01

    In this thesis we consider some cosmological implications of k-fields, which are general scalar fields with non-canonical kinetic terms in the action. Cosmological scenarios with k-essence are invoked in order to explain the observed late-time acceleration of the universe. These scenarios avoid the need for fine-tuned initial conditions (the ''coincidence problem'') because of the attractor-like dynamics of the k-essence field φ. We carry out a comprehensive study of attractor-like cosmological solutions (''trackers'') involving a k-essence scalar field φ and another matter component. The result of this study is a complete classification of k-essence Lagrangians that admit asymptotically stable tracking solutions, among all Lagrangians of the form p=K(φ)L(X). Using this classification, we select the class of models that describe the late-time acceleration and avoid the coincidence problem through the tracking mechanism. In the context of k-essence cosmology, the superluminal epoch does not lead to causality violations. We discuss the implications of superluminal signal propagation for possible causality violations in Lorentz-invariant field theories. Another application of k-fields was made in the new ekpyrotic scenario that attempts to solve the big-bang singularity problem by involving violation of the null energy condition in a model which combines the ekpyrotic/cyclic scenario with the ghost condensate theory and the curvation mechanism of production of adiabatic perturbations of metric. The Lagrangian of this theory, as well as of the ghost condensate model, contains a term with higher derivatives, which was added to the theory to stabilize its vacuum state. We find that this term may affect the dynamics of the cosmological evolution. Moreover, after a proper quantization, this term results in the existence of a new ghost field with negative energy, which leads to a catastrophic vacuum instability. We explain why one cannot treat this dangerous term as a

  10. Dark energy and bouncing universe from k-fields

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jin U

    2009-09-11

    In this thesis we consider some cosmological implications of k-fields, which are general scalar fields with non-canonical kinetic terms in the action. Cosmological scenarios with k-essence are invoked in order to explain the observed late-time acceleration of the universe. These scenarios avoid the need for fine-tuned initial conditions (the ''coincidence problem'') because of the attractor-like dynamics of the k-essence field {phi}. We carry out a comprehensive study of attractor-like cosmological solutions (''trackers'') involving a k-essence scalar field {phi} and another matter component. The result of this study is a complete classification of k-essence Lagrangians that admit asymptotically stable tracking solutions, among all Lagrangians of the form p=K({phi})L(X). Using this classification, we select the class of models that describe the late-time acceleration and avoid the coincidence problem through the tracking mechanism. In the context of k-essence cosmology, the superluminal epoch does not lead to causality violations. We discuss the implications of superluminal signal propagation for possible causality violations in Lorentz-invariant field theories. Another application of k-fields was made in the new ekpyrotic scenario that attempts to solve the big-bang singularity problem by involving violation of the null energy condition in a model which combines the ekpyrotic/cyclic scenario with the ghost condensate theory and the curvation mechanism of production of adiabatic perturbations of metric. The Lagrangian of this theory, as well as of the ghost condensate model, contains a term with higher derivatives, which was added to the theory to stabilize its vacuum state. We find that this term may affect the dynamics of the cosmological evolution. Moreover, after a proper quantization, this term results in the existence of a new ghost field with negative energy, which leads to a catastrophic vacuum instability. We explain

  11. Attainment of 40.5 pm spatial resolution using 300 kV scanning transmission electron microscope equipped with fifth-order aberration corrector.

    Science.gov (United States)

    Morishita, Shigeyuki; Ishikawa, Ryo; Kohno, Yuji; Sawada, Hidetaka; Shibata, Naoya; Ikuhara, Yuichi

    2018-02-01

    The achievement of a fine electron probe for high-resolution imaging in scanning transmission electron microscopy requires technological developments, especially in electron optics. For this purpose, we developed a microscope with a fifth-order aberration corrector that operates at 300 kV. The contrast flat region in an experimental Ronchigram, which indicates the aberration-free angle, was expanded to 70 mrad. By using a probe with convergence angle of 40 mrad in the scanning transmission electron microscope at 300 kV, we attained the spatial resolution of 40.5 pm, which is the projected interatomic distance between Ga-Ga atomic columns of GaN observed along [212] direction.

  12. Detection of Crossing White Matter Fibers with High-Order Tensors and Rank-k Decompositions

    KAUST Repository

    Jiao, Fangxiang; Gur, Yaniv; Johnson, Chris R.; Joshi, Sarang

    2011-01-01

    Fundamental to high angular resolution diffusion imaging (HARDI), is the estimation of a positive-semidefinite orientation distribution function (ODF) and extracting the diffusion properties (e.g., fiber directions). In this work we show that these two goals can be achieved efficiently by using homogeneous polynomials to represent the ODF in the spherical deconvolution approach, as was proposed in the Cartesian Tensor-ODF (CT-ODF) formulation. Based on this formulation we first suggest an estimation method for positive-semidefinite ODF by solving a linear programming problem that does not require special parameterization of the ODF. We also propose a rank-k tensor decomposition, known as CP decomposition, to extract the fibers information from the estimated ODF. We show that this decomposition is superior to the fiber direction estimation via ODF maxima detection as it enables one to reach the full fiber separation resolution of the estimation technique. We assess the accuracy of this new framework by applying it to synthetic and experimentally obtained HARDI data. © 2011 Springer-Verlag.

  13. An A Posteriori Error Analysis of Mixed Finite Element Galerkin Approximations to Second Order Linear Parabolic Problems

    KAUST Repository

    Memon, Sajid; Nataraj, Neela; Pani, Amiya Kumar

    2012-01-01

    In this article, a posteriori error estimates are derived for mixed finite element Galerkin approximations to second order linear parabolic initial and boundary value problems. Using mixed elliptic reconstructions, a posteriori error estimates in L∞(L2)- and L2(L2)-norms for the solution as well as its flux are proved for the semidiscrete scheme. Finally, based on a backward Euler method, a completely discrete scheme is analyzed and a posteriori error bounds are derived, which improves upon earlier results on a posteriori estimates of mixed finite element approximations to parabolic problems. Results of numerical experiments verifying the efficiency of the estimators have also been provided. © 2012 Society for Industrial and Applied Mathematics.

  14. Urban Environmental Problems

    International Nuclear Information System (INIS)

    Situma, F.D.P.

    1999-01-01

    The rapid urbanization and resultant heavy concentration of population in urban centres have led to many urban areas failing to provide the necessary infrastructure and amenities as the demands placed on them have overwhelmed their financial and institutional capacities. In many urban areas, the capacity for resource mobilization and delivery of social services has either broken down completely or tethers on breaking point. Although in 1986 the GoK launched a new strategy for the balanced development of rural and urban areas aimed at avoiding excessive concentration of population in urban areas, the fruits of this strategy are yet to be realized. As a result, developments in urban areas have been unsustainable and environmentally unsound. The general quality of the environment has deteriorated so much so that urgent policy intervention is required. Appropriate environmental management measures and practices are needed to address the current trend of spiralling environmental problems in the context of the existing legal and institutional frameworks and makes some proposals for reform to address these problems in order to make urban areas environmentally

  15. Target delineation in radiosurgery for cerebral arteriovenous malformations

    International Nuclear Information System (INIS)

    Guo, W.Y.; Nordell, B.; Karlsson, B.; Soederman, M.; Lindqvist, M.; Ericson, K.; Franck, A.; Lax, I.; Lindquist, C.

    1993-01-01

    A study of 6 selected arteriovenous malformation (AVM) patients was performed to investigate the feasibility of delineating an AVM on MR images and to compare the AVM volume outlined on different images. Conventional stereotaxic angiograms, stereotaxic MR images and MR angiograms using several different pulse sequences were obtained prior to radiosurgery. Treatment plans were made from the conventional stereotaxic angiograms. These plans were then transferred to a separate dose planning computer which displayed the MR images with the superimposed isodose lines. The radiated volumes of AVM and brain tissue were measured from these MR images. Last, an assessment was made of the radiation volume needed for an appropriate treatment of the AVM if the treatment plan was made from the MR images rather than from the conventional stereotaxic angiogram. It was possible to delineate medium and large size AVM nidi on stereotaxic MR images based on an integration of information obtained from various pulse sequences. The estimated volumes of the AVM nidi were found to be larger on the conventional stereotaxic angiograms than on the stereotaxic MR images. Consequently, a dose plan based on a conventional stereotaxic angiogram would result in a higher integral dose to the brain with the same target dose. By using reliable MR information it is expected that the volume of brain exposed to radiation could be decreased and the adverse effects of stereotactic radiosurgery for AVM thereby minimized. (orig.)

  16. Automatic delineation of functional lung volumes with 68Ga-ventilation/perfusion PET/CT.

    Science.gov (United States)

    Le Roux, Pierre-Yves; Siva, Shankar; Callahan, Jason; Claudic, Yannis; Bourhis, David; Steinfort, Daniel P; Hicks, Rodney J; Hofman, Michael S

    2017-10-10

    Functional volumes computed from 68 Ga-ventilation/perfusion (V/Q) PET/CT, which we have shown to correlate with pulmonary function test parameters (PFTs), have potential diagnostic utility in a variety of clinical applications, including radiotherapy planning. An automatic segmentation method would facilitate delineation of such volumes. The aim of this study was to develop an automated threshold-based approach to delineate functional volumes that best correlates with manual delineation. Thirty lung cancer patients undergoing both V/Q PET/CT and PFTs were analyzed. Images were acquired following inhalation of Galligas and, subsequently, intravenous administration of 68 Ga-macroaggreted-albumin (MAA). Using visually defined manual contours as the reference standard, various cutoff values, expressed as a percentage of the maximal pixel value, were applied. The average volume difference and Dice similarity coefficient (DSC) were calculated, measuring the similarity of the automatic segmentation and the reference standard. Pearson's correlation was also calculated to compare automated volumes with manual volumes, and automated volumes optimized to PFT indices. For ventilation volumes, mean volume difference was lowest (- 0.4%) using a 15%max threshold with Pearson's coefficient of 0.71. Applying this cutoff, median DSC was 0.93 (0.87-0.95). Nevertheless, limits of agreement in volume differences were large (- 31.0 and 30.2%) with differences ranging from - 40.4 to + 33.0%. For perfusion volumes, mean volume difference was lowest and Pearson's coefficient was highest using a 15%max threshold (3.3% and 0.81, respectively). Applying this cutoff, median DSC was 0.93 (0.88-0.93). Nevertheless, limits of agreement were again large (- 21.1 and 27.8%) with volume differences ranging from - 18.6 to + 35.5%. Using the 15%max threshold, moderate correlation was demonstrated with FEV1/FVC (r = 0.48 and r = 0.46 for ventilation and perfusion images, respectively

  17. Hypergeometric Series Solution to a Class of Second-Order Boundary Value Problems via Laplace Transform with Applications to Nanofluids

    Science.gov (United States)

    Ebaid, Abdelhalim; Wazwaz, Abdul-Majid; Alali, Elham; Masaedeh, Basem S.

    2017-03-01

    Very recently, it was observed that the temperature of nanofluids is finally governed by second-order ordinary differential equations with variable coefficients of exponential orders. Such coefficients were then transformed to polynomials type by using new independent variables. In this paper, a class of second-order ordinary differential equations with variable coefficients of polynomials type has been solved analytically. The analytical solution is expressed in terms of a hypergeometric function with generalized parameters. Moreover, applications of the present results have been applied on some selected nanofluids problems in the literature. The exact solutions in the literature were derived as special cases of our generalized analytical solution.

  18. Harnessing genomics for delineating conservation units.

    Science.gov (United States)

    Funk, W Chris; McKay, John K; Hohenlohe, Paul A; Allendorf, Fred W

    2012-09-01

    Genomic data have the potential to revolutionize the delineation of conservation units (CUs) by allowing the detection of adaptive genetic variation, which is otherwise difficult for rare, endangered species. In contrast to previous recommendations, we propose that the use of neutral versus adaptive markers should not be viewed as alternatives. Rather, neutral and adaptive markers provide different types of information that should be combined to make optimal management decisions. Genetic patterns at neutral markers reflect the interaction of gene flow and genetic drift that affects genome-wide variation within and among populations. This population genetic structure is what natural selection operates on to cause adaptive divergence. Here, we provide a new framework to integrate data on neutral and adaptive markers to protect biodiversity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. A higher-order nonlinear Schrödinger equation with variable coefficients

    OpenAIRE

    Carvajal, X.; Linares, F.

    2003-01-01

    We study the initial value problem (IVP) associated to a higher-order nonlinear Schrödinger equation with variable coefficients. Under some regularity on its coefficients we establish local well-posedness for the IVP for data in $H^s(\\mathbb R)$, $s\\ge1/4$, improving previous results [22]. The main ingredient in our proof is an estimate of the maximal function associated to the linear solution similar to the sharp one obtained for linear solutions of the Schrödinger and K...

  20. K-Means Clustering for Problems with Periodic Attributes

    Czech Academy of Sciences Publication Activity Database

    Vejmelka, Martin; Musílek, P.; Paluš, Milan; Pelikán, Emil

    2009-01-01

    Roč. 23, č. 4 (2009), s. 721-743 ISSN 0218-0014 R&D Projects: GA AV ČR 1ET400300513 EU Projects: European Commission(XE) 517133 - BRACCIA Institutional research plan: CEZ:AV0Z10300504 Keywords : clustering algorithms * similarity measures * K- means * periodic attributes Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.512, year: 2009

  1. Validation of simple quantification methods for 18F FP CIT PET Using Automatic Delineation of volumes of interest based on statistical probabilistic anatomical mapping and isocontour margin setting

    International Nuclear Information System (INIS)

    Kim, Yong Il; Im, Hyung Jun; Paeng, Jin Chul; Lee, Jae Sung; Eo, Jae Seon; Kim, Dong Hyun; Kim, Euishin E.; Kang, Keon Wook; Chung, June Key; Lee Dong Soo

    2012-01-01

    18 F FP CIT positron emission tomography (PET) is an effective imaging for dopamine transporters. In usual clinical practice, 18 F FP CIT PET is analyzed visually or quantified using manual delineation of a volume of interest (VOI) fir the stratum. in this study, we suggested and validated two simple quantitative methods based on automatic VOI delineation using statistical probabilistic anatomical mapping (SPAM) and isocontour margin setting. Seventy five 18 F FP CIT images acquired in routine clinical practice were used for this study. A study-specific image template was made and the subject images were normalized to the template. afterwards, uptakes in the striatal regions and cerebellum were quantified using probabilistic VOI based on SPAM. A quantitative parameter, Q SPAM, was calculated to simulate binding potential. additionally, the functional volume of each striatal region and its uptake were measured in automatically delineated VOI using isocontour margin setting. Uptake volume product(Q UVP) was calculated for each striatal region. Q SPAMa nd Q UVPw as calculated for each visual grading and the influence of cerebral atrophy on the measurements was tested. Image analyses were successful in all the cases. Both the Q SPAMa nd Q UVPw ere significantly different according to visual grading (0.001). The agreements of Q UVPa nd Q SPAMw ith visual grading were slight to fair for the caudate nucleus (K= 0.421 and 0.291, respectively) and good to prefect to the putamen (K=0.663 and 0.607, respectively). Also, Q SPAMa nd Q UVPh ad a significant correlation with each other (0.001). Cerebral atrophy made a significant difference in Q SPAMa nd Q UVPo f the caudate nuclei regions with decreased 18 F FP CIT uptake. Simple quantitative measurements of Q SPAMa nd Q UVPs howed acceptable agreement with visual grad-ing. although Q SPAMi n some group may be influenced by cerebral atrophy, these simple methods are expected to be effective in the quantitative analysis of F FP

  2. Historical Delineation of Landscape Units Using Physical Geographic Characteristics and Land Use/Cover Change

    Science.gov (United States)

    Campos-Campos, Oswaldo; Cruz-Cárdenas, Gustavo; Aquino, Roque Juan Carrasco; Moncayo-Estrada, Rodrigo; Machuca, Martha Alicia Velázquez; Meléndez, Luis Arturo Ávila

    2018-03-01

    Landscape units are conceived as a part of the territory that share similar physical and geographic characteristics. Their delineation can contribute to identify the physical and social dynamics that emerge in the spatial environment and to propose strategies of planning and management of the territory. The main objective was to make a historical delineation of landscape units in the Duero river basin that demonstrate the dynamics of changes in the territory, the description of the actors involved, and the affectations in the natural and social environment. We analyzed the vegetation change and urban growth from 1983 to 2014, incorporating climatic, edaphic, and topographic variables. A Principal Component Analysis was performed with the information and results were used in Maximum Likelihood procedure to define different clusters based on environmental characteristics. We defined five categories from the Landsat images. Results showed landscape units with homogeneous environmental characteristics and some differences in the units' delineation were mainly influenced by political and socioeconomic factors. Temporally there was an increased tendency of landscape units, three in 1983, nine in 1990, 1995, 2000 and 2011, and eight in 2014. This increase resulted from territory fragmentation because of berries and avocado cultivars expansion over wooded area.

  3. By-passing the sign-problem in Fermion Path Integral Monte Carlo simulations by use of high-order propagators

    Science.gov (United States)

    Chin, Siu A.

    2014-03-01

    The sign-problem in PIMC simulations of non-relativistic fermions increases in serverity with the number of fermions and the number of beads (or time-slices) of the simulation. A large of number of beads is usually needed, because the conventional primitive propagator is only second-order and the usual thermodynamic energy-estimator converges very slowly from below with the total imaginary time. The Hamiltonian energy-estimator, while more complicated to evaluate, is a variational upper-bound and converges much faster with the total imaginary time, thereby requiring fewer beads. This work shows that when the Hamiltonian estimator is used in conjunction with fourth-order propagators with optimizable parameters, the ground state energies of 2D parabolic quantum-dots with approximately 10 completely polarized electrons can be obtain with ONLY 3-5 beads, before the onset of severe sign problems. This work was made possible by NPRP GRANT #5-674-1-114 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the author.

  4. Third-order-accurate numerical methods for efficient, large time-step solutions of mixed linear and nonlinear problems

    Energy Technology Data Exchange (ETDEWEB)

    Cobb, J.W.

    1995-02-01

    There is an increasing need for more accurate numerical methods for large-scale nonlinear magneto-fluid turbulence calculations. These methods should not only increase the current state of the art in terms of accuracy, but should also continue to optimize other desired properties such as simplicity, minimized computation, minimized memory requirements, and robust stability. This includes the ability to stably solve stiff problems with long time-steps. This work discusses a general methodology for deriving higher-order numerical methods. It also discusses how the selection of various choices can affect the desired properties. The explicit discussion focuses on third-order Runge-Kutta methods, including general solutions and five examples. The study investigates the linear numerical analysis of these methods, including their accuracy, general stability, and stiff stability. Additional appendices discuss linear multistep methods, discuss directions for further work, and exhibit numerical analysis results for some other commonly used lower-order methods.

  5. MR-based automatic delineation of volumes of interest in human brain PET images using probability maps

    DEFF Research Database (Denmark)

    Svarer, Claus; Madsen, Karina; Hasselbalch, Steen G.

    2005-01-01

    subjects' MR-images, where VOI sets have been defined manually. High-resolution structural MR-images and 5-HT(2A) receptor binding PET-images (in terms of (18)F-altanserin binding) from 10 healthy volunteers and 10 patients with mild cognitive impairment were included for the analysis. A template including...... 35 VOIs was manually delineated on the subjects' MR images. Through a warping algorithm template VOI sets defined from each individual were transferred to the other subjects MR-images and the voxel overlap was compared to the VOI set specifically drawn for that particular individual. Comparisons were...... delineation of the VOI set. The approach was also shown to work equally well in individuals with pronounced cerebral atrophy. Probability-map-based automatic delineation of VOIs is a fast, objective, reproducible, and safe way to assess regional brain values from PET or SPECT scans. In addition, the method...

  6. Analisis Kemampuan Berpikir Tingkat Tinggi Mahasiswa (Higher Order Thinking dalam Menyelesaikan Soal Konsep Optika melalui Model Problem Based Learning

    Directory of Open Access Journals (Sweden)

    Nurhayati Nurhayati

    2017-12-01

    Full Text Available Abstract This study aims to describe the ability of higher order thinking students in solving the problem of the concept of optics after given the learning with problem-based learning model. This research uses a descriptive method with quantitative approach. The subjects of the research are students of the second semester of physics education study program, amounting to 19 people. Data collection techniques used are two tier multiple choice shaped test consisting of eight questions include the level of analyzing, evaluating and creating. Based on the results of data analysis, it is known that the ability of high-level thinking of students in optical learning has enough categories with the following details: (1 The percentage of students who have excellent high-level thinking skills is 15.79%, good category of 31.58%, enough category of 42.11%, and category less than 10.53%; (2 The percentage of student ability in answer about level of analyze equal to 68.42%, student ability in answer about evaluation level 57.89% and equal to 53.51% for student ability in answer level question create. Keywords: higher order thinking, optics, problem-based learning model Abstrak Penelitian ini bertujuan untuk mendeskripsikan kemampuan berpikir tingkat tinggi mahasiswa (higher order thinking dalam menyelesaikan soal konsep optika setelah diberikan pembelajaran dengan model problem based learning. Metode penelitian yang digunakan adalah metode deskriptif dengan pendekatan kuantitatif. Subjek penelitian yaitu mahasiswa semester II program studi pendidikan fisika yang berjumlah 19 orang. Teknik pengumpulan data yang digunakan adalah tes berbentuk two tier multiple choice yang terdiri dari delapan soal meliputi tingkatan menganalisis, mengevaluasi dan mencipta. Berdasarkan hasil analisis data, diketahui bahwa kemampuan berpikir tingkat tinggi mahasiswa dalam pembelajaran optika memiliki kategori cukup dengan rincian sebagai berikut: (1 Persentase mahasiswa yang

  7. High order methods for the integration of the Bateman equations and other problems of the form of y‧ = F(y,t)y

    Science.gov (United States)

    Josey, C.; Forget, B.; Smith, K.

    2017-12-01

    This paper introduces two families of A-stable algorithms for the integration of y‧ = F (y , t) y: the extended predictor-corrector (EPC) and the exponential-linear (EL) methods. The structure of the algorithm families are described, and the method of derivation of the coefficients presented. The new algorithms are then tested on a simple deterministic problem and a Monte Carlo isotopic evolution problem. The EPC family is shown to be only second order for systems of ODEs. However, the EPC-RK45 algorithm had the highest accuracy on the Monte Carlo test, requiring at least a factor of 2 fewer function evaluations to achieve a given accuracy than a second order predictor-corrector method (center extrapolation / center midpoint method) with regards to Gd-157 concentration. Members of the EL family can be derived to at least fourth order. The EL3 and the EL4 algorithms presented are shown to be third and fourth order respectively on the systems of ODE test. In the Monte Carlo test, these methods did not overtake the accuracy of EPC methods before statistical uncertainty dominated the error. The statistical properties of the algorithms were also analyzed during the Monte Carlo problem. The new methods are shown to yield smaller standard deviations on final quantities as compared to the reference predictor-corrector method, by up to a factor of 1.4.

  8. On k-summability of formal solutions for certain partial differential operators with polynomial coefficients

    Directory of Open Access Journals (Sweden)

    Kunio Ichinobe

    2015-01-01

    Full Text Available We study the \\(k\\-summability of divergent formal solutions for the Cauchy problem of certain linear partial differential operators with coefficients which are polynomial in \\(t\\. We employ the method of successive approximation in order to construct the formal solutions and to obtain the properties of analytic continuation of the solutions of convolution equations and their exponential growth estimates.

  9. Tumor and target delineation: current research and future challenges

    International Nuclear Information System (INIS)

    Austin-Seymour, Mary; Chen, George T.Y.; Rosenman, Julian; Michalski, Jeff; Lindsley, Karen; Goitein, Michael

    1995-01-01

    In the past decade, significant progress has been made in the imaging of tumors, three dimensional (3D) treatment planning, and radiation treatment delivery. At this time one of the greatest challenges for conformal radiation therapy is the accurate delineation of tumor and target volumes. The physician encounters many uncertainties in the process of defining both tumor and target. The sources of these uncertainties are discussed, as well as the issues requiring study to reduce these uncertainties

  10. A component of DNA double-strand break repair is dependent on the spatial orientation of the lesions within the higher-order structures of chromatin

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, P.J.; Bryant, P.E. (Saint Andrews Univ. (United Kingdom))

    1994-11-01

    By the use of a modified neutral filter elution procedure variations in the repair of DNA dsb have been observed between the ionising radiation sensitive mutant xrs-5 and the parent cell line CHO-K1. Conventional neutral filter elution requires harsh lysis conditions to remove higher-order chromatin structures which interfere with elution of DNA containing dsb. By lysing cells with non-ionic detergent in the presence of 2 mol dm[sup -3] salt, histone-depleted structures that retain the higher-order nuclear matrix organization, including chromatin loops, can be produced. Elution from these structures will only occur if two or more dsb lie within a single-looped domain delineated by points of attachment to the nuclear matrix. Repair experiments indicate that in CHO cells repair of dsb in loops containing multiple dsb are repaired with slow kinetics whilst dsb occurring in loops containing single dsb are repaired with fast kinetics. Xrs-5 cells are defective in the repair of multiply damaged loops. This work indicates that the spatial orientation of dsb in the higher-order structures of chromatin are a possible factor in the repair of these lesions. (Author).

  11. A component of DNA double-strand break repair is dependent on the spatial orientation of the lesions within the higher-order structures of chromatin

    International Nuclear Information System (INIS)

    Johnston, P.J.; Bryant, P.E.

    1994-01-01

    By the use of a modified neutral filter elution procedure variations in the repair of DNA dsb have been observed between the ionising radiation sensitive mutant xrs-5 and the parent cell line CHO-K1. Conventional neutral filter elution requires harsh lysis conditions to remove higher-order chromatin structures which interfere with elution of DNA containing dsb. By lysing cells with non-ionic detergent in the presence of 2 mol dm -3 salt, histone-depleted structures that retain the higher-order nuclear matrix organization, including chromatin loops, can be produced. Elution from these structures will only occur if two or more dsb lie within a single-looped domain delineated by points of attachment to the nuclear matrix. Repair experiments indicate that in CHO cells repair of dsb in loops containing multiple dsb are repaired with slow kinetics whilst dsb occurring in loops containing single dsb are repaired with fast kinetics. Xrs-5 cells are defective in the repair of multiply damaged loops. This work indicates that the spatial orientation of dsb in the higher-order structures of chromatin are a possible factor in the repair of these lesions. (Author)

  12. Existence of Triple Positive Solutions for Second-Order Discrete Boundary Value Problems

    Directory of Open Access Journals (Sweden)

    Yanping Guo

    2007-01-01

    Full Text Available By using a new fixed-point theorem introduced by Avery and Peterson (2001, we obtain sufficient conditions for the existence of at least three positive solutions for the equation Δ2x(k−1+q(kf(k,x(k,Δx(k=0, for k∈{1,2,…,n−1}, subject to the following two boundary conditions: x(0=x(n=0 or x(0=Δx(n−1=0, where n≥3.

  13. Existence of positive solutions for nonlocal second-order boundary value problem with variable parameter in Banach spaces

    Directory of Open Access Journals (Sweden)

    Zhang Peiguo

    2011-01-01

    Full Text Available Abstract By obtaining intervals of the parameter λ, this article investigates the existence of a positive solution for a class of nonlinear boundary value problems of second-order differential equations with integral boundary conditions in abstract spaces. The arguments are based upon a specially constructed cone and the fixed point theory in cone for a strict set contraction operator. MSC: 34B15; 34B16.

  14. A comparison of latent class, K-means, and K-median methods for clustering dichotomous data.

    Science.gov (United States)

    Brusco, Michael J; Shireman, Emilie; Steinley, Douglas

    2017-09-01

    The problem of partitioning a collection of objects based on their measurements on a set of dichotomous variables is a well-established problem in psychological research, with applications including clinical diagnosis, educational testing, cognitive categorization, and choice analysis. Latent class analysis and K-means clustering are popular methods for partitioning objects based on dichotomous measures in the psychological literature. The K-median clustering method has recently been touted as a potentially useful tool for psychological data and might be preferable to its close neighbor, K-means, when the variable measures are dichotomous. We conducted simulation-based comparisons of the latent class, K-means, and K-median approaches for partitioning dichotomous data. Although all 3 methods proved capable of recovering cluster structure, K-median clustering yielded the best average performance, followed closely by latent class analysis. We also report results for the 3 methods within the context of an application to transitive reasoning data, in which it was found that the 3 approaches can exhibit profound differences when applied to real data. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Non-Gaussianity from self-ordering scalar fields

    International Nuclear Information System (INIS)

    Figueroa, Daniel G.; Caldwell, Robert R.; Kamionkowski, Marc

    2010-01-01

    The Universe may harbor relics of the post-inflationary epoch in the form of a network of self-ordered scalar fields. Such fossils, while consistent with current cosmological data at trace levels, may leave too weak an imprint on the cosmic microwave background and the large-scale distribution of matter to allow for direct detection. The non-Gaussian statistics of the density perturbations induced by these fields, however, permit a direct means to probe for these relics. Here we calculate the bispectrum that arises in models of self-ordered scalar fields. We find a compact analytic expression for the bispectrum, evaluate it numerically, and provide a simple approximation that may be useful for data analysis. The bispectrum is largest for triangles that are aligned (have edges k 1 ≅2k 2 ≅2k 3 ) as opposed to the local-model bispectrum, which peaks for squeezed triangles (k 1 ≅k 2 >>k 3 ), and the equilateral bispectrum, which peaks at k 1 ≅k 2 ≅k 3 . We estimate that this non-Gaussianity should be detectable by the Planck satellite if the contribution from self-ordering scalar fields to primordial perturbations is near the current upper limit.

  16. Cytotoxic activity of vitamins K1, K2 and K3 against human oral tumor cell lines.

    Science.gov (United States)

    Okayasu, H; Ishihara, M; Satoh, K; Sakagami, H

    2001-01-01

    Vitamin K1, K2 and K3 were compared for their cytotoxic activity, radical generation and O2- scavenging activity. Among these compounds, vitamin K3 showed the highest cytotoxic activity against human oral tumor cell lines (HSC-2, HSG), human promyelocytic leukemic cell line (HL-60) and human gingival fibroblast (HGF). Vitamin K3 induced internucleosomal DNA fragmentation in HL-60 cells, but not in HSC-2 or HSG cells. The cytotoxic activity of vitamins K2 and K1 was one and two orders lower, respectively, than K3. Vitamin K2, but not vitamin K3, showed tumor-specific cytotoxic action. ESR spectroscopy showed that only vitamin K3 produced radical(s) under alkaline condition and most potently enhanced the radical intensity of sodium ascorbate and scavenged O2- (generated by hypoxanthine-xanthine oxidase reaction system); vitamin K2 was much less active whereas vitamin K1 was inactive. These data suggest that the cytotoxic activity of vitamin K3 is generated by radical-mediated oxidation mechanism and that this vitamin has two opposing actions (that is, antioxidant and prooxidant), depending on the experimental conditions.

  17. Lhx6 delineates a pathway mediating innate reproductive behaviors from the amygdala to the hypothalamus.

    Science.gov (United States)

    Choi, Gloria B; Dong, Hong-Wei; Murphy, Andrew J; Valenzuela, David M; Yancopoulos, George D; Swanson, Larry W; Anderson, David J

    2005-05-19

    In mammals, innate reproductive and defensive behaviors are mediated by anatomically segregated connections between the amygdala and hypothalamus. This anatomic segregation poses the problem of how the brain integrates activity in these circuits when faced with conflicting stimuli eliciting such mutually exclusive behaviors. Using genetically encoded and conventional axonal tracers, we have found that the transcription factor Lhx6 delineates the reproductive branch of this pathway. Other Lhx proteins mark neurons in amygdalar nuclei implicated in defense. We have traced parallel projections from the posterior medial amygdala, activated by reproductive or defensive olfactory stimuli, respectively, to a point of convergence in the ventromedial hypothalamus. The opposite neurotransmitter phenotypes of these convergent projections suggest a "gate control" mechanism for the inhibition of reproductive behaviors by threatening stimuli. Our data therefore identify a potential neural substrate for integrating the influences of conflicting behavioral cues and a transcription factor family that may contribute to the development of this substrate.

  18. Tumor bed delineation for external beam accelerated partial breast irradiation: A systematic review

    International Nuclear Information System (INIS)

    Yang, T. Jonathan; Tao, Randa; Elkhuizen, Paula H.M.; Vliet-Vroegindeweij, Corine van; Li, Guang; Powell, Simon N.

    2013-01-01

    In recent years, accelerated partial breast irradiation (APBI) has been considered an alternative to whole breast irradiation for patients undergoing breast-conserving therapy. APBI delivers higher doses of radiation in fewer fractions to the post-lumpectomy tumor bed with a 1–2 cm margin, targeting the area at the highest risk of local recurrence while sparing normal breast tissue. However, there are inherent challenges in defining accurate target volumes for APBI. Studies have shown that significant interobserver variation exists among radiation oncologists defining the lumpectomy cavity, which raises the question of how to improve the accuracy and consistency in the delineation of tumor bed volumes. The combination of standardized guidelines and surgical clips significantly improves an observer’s ability in delineation, and it is the standard in multiple ongoing external-beam APBI trials. However, questions about the accuracy of the clips to mark the lumpectomy cavity remain, as clips only define a few points at the margin of the cavity. This paper reviews the techniques that have been developed so far to improve target delineation in APBI delivered by conformal external beam radiation therapy, including the use of standardized guidelines, surgical clips or fiducial markers, pre-operative computed tomography imaging, and additional imaging modalities, including magnetic resonance imaging, ultrasound imaging, and positron emission tomography/computed tomography. Alternatives to post-operative APBI, future directions, and clinical recommendations were also discussed

  19. Discontinuous finite element treatment of duct problems in transport calculations

    International Nuclear Information System (INIS)

    Mirza, A. M.; Qamar, S.

    1998-01-01

    A discontinuous finite element approach is presented to solve the even-parity Boltzmann transport equation for duct problems. Presence of ducts in a system results in the streaming of particles and hence requires the employment of higher order angular approximations to model the angular flux. Conventional schemes based on the use of continuous trial functions require the same order of angular approximations to be used everywhere in the system, resulting in wastage of computational resources. Numerical investigations for the test problems presented in this paper indicate that the discontinuous finite elements eliminate the above problems and leads to computationally efficient and economical methods. They are also found to be more suitable for treating the sharp changes in the angular flux at duct-observer interfaces. The new approach provides a single-pass alternate to extrapolation and interactive schemes which need multiple passes of the solution strategy to acquire convergence. The method has been tested with the help of two case studies, namely straight and dog-leg duct problems. All results have been verified against those obtained from Monte Carlo simulations and K/sup +/ continuous finite element method. (author)

  20. Risky procedures by nurses in hospitals: problems and (contemplated) refusals of orders by physicians, and views of physicians and nurses: a questionnaire survey

    NARCIS (Netherlands)

    de Bie, J.; Cuperus-Bosma, J.M.; van der Jagt, M.A.; Gevers, J.K.M.; van der Wal, G.

    2005-01-01

    Occurrence of problems with, refusals of orders and contemplated refusals of orders for risky procedures by nurses in Dutch hospitals and views on the safety of performance was studied using postal questionnaires (600 physicians and 3200 nurses, response 60-71%). Of the respondents, 11-30%

  1. Interobserver variability in gross tumor volume delineation for hepatocellular carcinoma. Results of Korean Radiation Oncology Group 1207 study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Suk [Jeju National University School of Medicine, Department of Radiation Oncology, Jeju National University Hospital, Jeju (Korea, Republic of); Kim, Jun Won; Lee, Ik Jae [Yonsei University College of Medicine, Department of Radiation Oncology, Gangnam Severance Hospital, Seoul (Korea, Republic of); Yoon, Won Sup [Korea University Medical Center, Department of Radiation Oncology, Ansan Hospital, Ansan (Korea, Republic of); Kang, Min Kyu [Kyungpook National University School of Medicine, Department of Radiation Oncology, Daegu (Korea, Republic of); Kim, Tae Hyun [National Cancer Center, Center for Liver Cancer, Goyang (Korea, Republic of); Kim, Jin Hee [Keimyung University School of Medicine, Department of Radiation Oncology, Dongsan Medical Center, Daegu (Korea, Republic of); Lee, Hyung-Sik [Dong-A University College of Medicine, Department of Radiation Oncology, Busan (Korea, Republic of); Park, Hee Chul [Sungkyunkwan University School of Medicine, Department of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of); Jang, Hong Seok; Kay, Chul Seung [The Catholic University of Korea College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of); Yoon, Sang Min [University of Ulsan College of Medicine, Department of Radiation Oncology, Asan Medical Center, Seoul (Korea, Republic of); Kim, Mi-Sook [Korea Institute of Radiological and Medical Sciences, Department of Radiation Oncology, Seoul (Korea, Republic of); Seong, Jinsil [Yonsei University College of Medicine, Department of Radiation Oncology, Severance Hospital, Seodaemun-gu, Seoul (Korea, Republic of)

    2016-10-15

    There has been increasing use of external beam radiotherapy for localized treatment of hepatocellular carcinoma (HCC) with both palliative and curative intent. Quality control of target delineation in primary HCC is essential to deliver adequate doses of radiation to the primary tumor while preserving adjacent healthy organs. We analyzed interobserver variability in gross tumor volume (GTV) delineation for HCC. Twelve radiation oncologists specializing in liver malignancy participated in a multi-institutional contouring dummy-run study of nine HCC cases and independently delineated GTV on the same set of provided computed tomography images. Quantitative analysis was performed using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE) with kappa statistics calculating agreement between physicians. To quantify the interobserver variability of GTV delineations, the ratio of the actual delineated volume to the estimated consensus volume (STAPLE), the ratio of the common and encompassing volumes, and the coefficient of variation were calculated. The median kappa agreement level was 0.71 (range 0.28-0.86). The ratio of the actual delineated volume to the estimated consensus volume ranged from 0.19 to 1.93 (median 0.94) for all cases. The ratio of the common and encompassing volumes ranged from 0.001 to 0.56 (median 0.25). The coefficient of variation for GTV delineation ranged from 8 to 57 % (median 26 %). The interobserver variability in target delineation of HCC GTV in this study is noteworthy. Multi-institution studies involving radiotherapy for HCC require appropriate quality assurance programs for target delineation. (orig.) [German] Die externe kurative Strahlentherapie ist zunehmend bei der lokalisierten Behandlung hepatozellulaerer Karzinome (HCC) in palliativer und kurativer Absicht in Gebrauch. Eine Qualitaetskontrolle der Zielabgrenzung beim primaeren HCC ist entscheidend, um die passende Dosis fuer die

  2. AC transmission, with very high voltages and the 750 kV line

    Energy Technology Data Exchange (ETDEWEB)

    Bocker, H

    1964-01-01

    The economic case for adoption of extra-high voltages for transmitting electric power over distances of the order of 1000 km is discussed. Some special technical developments for solving the problems attached to such high voltages are briefly discussed, particularly in the fields of switching and transients suppression. The first 750-kV projects in Canada and Russia are mentioned. Equipment, e.g., bushings, transformers, etc., operating at such voltages are illustrated.

  3. Inter-observer variation in delineation of the heart and left anterior descending coronary artery in radiotherapy for breast cancer

    DEFF Research Database (Denmark)

    Laugaard Lorenzen, Ebbe; Taylor, C. W.; Maraldo, M.

    2013-01-01

    receiving left breast radiotherapy. The delineations were carried out twice, first without guidelines and then with a set of common guidelines. RESULTS: For the heart, most spatial variation in delineation was near the base of the heart whereas for the LADCA most variation was in its length at the apex...

  4. Definition and delineation of the clinical target volume for rectal cancer

    International Nuclear Information System (INIS)

    Roels, Sarah; Duthoy, Wim; Haustermans, Karin; Penninckx, Freddy; Vandecaveye, Vincent; Boterberg, Tom; Neve, Wilfried de

    2006-01-01

    Purpose: Optimization of radiation techniques to maximize local tumor control and to minimize small bowel toxicity in locally advanced rectal cancer requires proper definition and delineation guidelines for the clinical target volume (CTV). The purpose of this investigation was to analyze reported data on the predominant locations and frequency of local recurrences and lymph node involvement in rectal cancer, to propose a definition of the CTV for rectal cancer and guidelines for its delineation. Methods and Materials: Seven reports were analyzed to assess the incidence and predominant location of local recurrences in rectal cancer. The distribution of lymphatic spread was analyzed in another 10 reports to record the relative frequency and location of metastatic lymph nodes in rectal cancer, according to the stage and level of the primary tumor. Results: The mesorectal, posterior, and inferior pelvic subsites are most at risk for local recurrences, whereas lymphatic tumor spread occurs mainly in three directions: upward into the inferior mesenteric nodes; lateral into the internal iliac lymph nodes; and, in a few cases, downward into the external iliac and inguinal lymph nodes. The risk for recurrence or lymph node involvement is related to the stage and the level of the primary lesion. Conclusion: Based on a review of articles reporting on the incidence and predominant location of local recurrences and the distribution of lymphatic spread in rectal cancer, we defined guidelines for CTV delineation including the pelvic subsites and lymph node groups at risk for microscopic involvement. We propose to include the primary tumor, the mesorectal subsite, and the posterior pelvic subsite in the CTV in all patients. Moreover, the lateral lymph nodes are at high risk for microscopic involvement and should also be added in the CTV

  5. Dynamics of a two-dimensional order-disorder transition

    International Nuclear Information System (INIS)

    Sahni, P.S.; Dee, G.; Gunton, J.D.; Phani, M.; Lebowitz, J.L.; Kalos, M.

    1981-01-01

    We present results of a Monte Carlo study of the time development of a two-dimensional order-disorder model binary alloy following a quench to low temperature from a disordered, high-temperature state. The behavior is qualitatively quite similar to that seen in a recent study of a three-dimensional system. The structure function exhibits a scaling of the form K 2 (t)S(k,t) = G(k/K(t)) where the moment K(t) decreases with time approximately like t/sup -1/2/. If one interprets this moment as being inversely proportional to the domain size, the characteristic domain growth rate is proportional to t/sup -1/2/. Additional insight into this time evolution is obtained from studying the development of the short-range order, as well as from monitoring the growth of a compact ordered domain embedded in a region of opposite order. All these results are consistent with the picture of domain growth as proposed by Lifshitz and by Cahn and Allen

  6. Preliminary assessment of clinoptilolite K/Ar results from Yucca Mountain, Nevada: A potential high-level radioactive waste repository site

    International Nuclear Information System (INIS)

    WoldeGabriel, G.; Bish, D.L.; Broxton, D.E.; Chipera, S.J.

    1992-01-01

    At Yucca Mountain, evidence for at least three distinct temporal groups of clinoptilolites can be delineated from the preliminary K/Ar dates (2--3 Ma; 4--5 Ma; 7--11 Ma). The older K/Ar dates that are similar to published illite/smectite ages (9--12 Ma) may be crystallization ages, whereas the younger dates probably represent continued diagenetic reactions of older clinoptilolites with percolating fluids. The K/Ar dates increase with depth, suggesting minimal argon loss in the deeper samples. Internal consistency of the clinoptilolite K/Ar results at different levels within the drill holes suggest that dating of K-rich zeolites may provide useful information for assessing the zeolitization at Yucca Mountain. Variations in the K/Ar dates are probably related to Ar loss during dissolution of older clinoptilolites and to contamination by finely crystalline feldspars

  7. The Application of Problem-Based Learning Strategy to Increase High Order Thinking Skills of Senior Vocational School Students

    Science.gov (United States)

    Suprapto, Edy; Fahrizal; Priyono; Basri, K.

    2017-01-01

    This research is to apply and develop a strategy of problem-based learning to increase the ability of higher order thinking skills of senior vocational schools students. The research was done due to a fact that the quality of outputs of the senior vocational schools has not met the competency needed by the stakeholders in the field, that has made…

  8. Quantifying the performance of automated GIS-based geomorphological approaches for riparian zone delineation using digital elevation models

    OpenAIRE

    D. Fernández; J. Barquín; M. Álvarez-Cabria; F. J. Peñas

    2012-01-01

    Riparian zone delineation is a central issue for managing rivers and adjacent areas; however, criteria used to delineate them are still under debate. The area inundated by a 50-yr flood has been indicated as an optimal hydrological descriptor for riparian areas. This detailed hydrological information is usually only available for populated areas at risk of flooding. In this work we created several floodplain surfaces by means of two different GIS-based geomorphological appro...

  9. Nuclear order in copper

    DEFF Research Database (Denmark)

    Annila, A.J.; Clausen, K.N.; Lindgård, P-A.

    1990-01-01

    A new ordering vector k=(2π/a)(0, 2/3, 2/3) for fcc antiferromagnets has been found by neutron-diffraction experiments at nanokelvin temperatures in the nuclear-spin system of a 65Cu single crystal. The corresponding reflection together with the previously observed (100) Bragg peak show the prese......A new ordering vector k=(2π/a)(0, 2/3, 2/3) for fcc antiferromagnets has been found by neutron-diffraction experiments at nanokelvin temperatures in the nuclear-spin system of a 65Cu single crystal. The corresponding reflection together with the previously observed (100) Bragg peak show...

  10. K- and L-shell ionization cross sections for deuterons calculated in the ECPSSR theory

    International Nuclear Information System (INIS)

    Cohen, D.D.

    1989-01-01

    Ionization cross sections for K and L subshells are tabulated according to target atomic number and incident deuteron energy. Deuteron energies between 100 keV and 10 MeV and selected targets between C and Am for the K shell and between Ar and Am for the L subshells are used. The cross sections have been calculated in the plane-wave Born approximation (PWBA) with corrections for energy loss (E), Coulomb deflection (C), perturbed stationary states (PSS), and relativistic (R) effects (ECPSSR). Differences between the computational approach of Cohen and Harrigan and that of Brandt and Lapicki are delineated, and the ratios of the resulting cross sections are tabulated. Copyright 1989 Academic Press, Inc

  11. Molecular epidemiology of Klebsiella pneumoniae K1 and K2 isolates in Japan.

    Science.gov (United States)

    Harada, Sohei; Ishii, Yoshikazu; Saga, Tomoo; Aoki, Kotaro; Tateda, Kazuhiro

    2018-03-20

    Although severe infections caused by hypervirulent Klebsiella pneumoniae isolates, such as K1 isolates belonging to sequence type (ST) 23, have been a significant problem in Asian countries, epidemiology of these isolates in Japan remains unclear. We performed a nationwide molecular epidemiological study of K. pneumoniae K1 and K2 isolates in Japan. Of the 259K. pneumoniae isolates collected, 14 and 16 isolates were identified as capsular genotypes K1 and K2, respectively. All K1 isolates were ST23 or its closely related clones and showed high genetic similarity by pulsed-field gel electrophoresis (PFGE) and the DiversiLab system (DL). K2 isolates, belonging to ST14, ST25, ST65, ST86, and ST110, were more genetically diverse than K1 isolates. Isolates belonging to a specific ST showed identical virulence gene profiles with a few exceptions. PFGE and DL results using K1 and K2 isolates were generally in agreement. Copyright © 2018. Published by Elsevier Inc.

  12. Segmentation of Brain Lesions in MRI and CT Scan Images: A Hybrid Approach Using k-Means Clustering and Image Morphology

    Science.gov (United States)

    Agrawal, Ritu; Sharma, Manisha; Singh, Bikesh Kumar

    2018-04-01

    Manual segmentation and analysis of lesions in medical images is time consuming and subjected to human errors. Automated segmentation has thus gained significant attention in recent years. This article presents a hybrid approach for brain lesion segmentation in different imaging modalities by combining median filter, k means clustering, Sobel edge detection and morphological operations. Median filter is an essential pre-processing step and is used to remove impulsive noise from the acquired brain images followed by k-means segmentation, Sobel edge detection and morphological processing. The performance of proposed automated system is tested on standard datasets using performance measures such as segmentation accuracy and execution time. The proposed method achieves a high accuracy of 94% when compared with manual delineation performed by an expert radiologist. Furthermore, the statistical significance test between lesion segmented using automated approach and that by expert delineation using ANOVA and correlation coefficient achieved high significance values of 0.986 and 1 respectively. The experimental results obtained are discussed in lieu of some recently reported studies.

  13. Field Biogeochemical Measurements in Support of Remote Sensing Signatures and Characterization of Permafrost Terrain: Integrated Technologies for Delineating Permafrost and Ground-State Conditions

    Science.gov (United States)

    2015-03-01

    Characterization of Permafrost Terrain Integrated Technologies for Delineating Permafrost and Ground-State Conditions En gi ne er R es ea rc h an d...Signatures and Characterization of Permafrost Terrain Integrated Technologies for Delineating Permafrost and Ground-State Conditions Robyn A. Barbato...Center-Directed Research Project, “Integrated Technologies for Delineating Permafrost and Ground-State Conditions” ERDC TR-15-1 ii Abstract This

  14. Historical Delineation of Landscape Units Using Physical Geographic Characteristics and Land Use/Cover Change

    Directory of Open Access Journals (Sweden)

    Campos-Campos Oswaldo

    2018-03-01

    Full Text Available Landscape units are conceived as a part of the territory that share similar physical and geographic characteristics. Their delineation can contribute to identify the physical and social dynamics that emerge in the spatial environment and to propose strategies of planning and management of the territory. The main objective was to make a historical delineation of landscape units in the Duero river basin that demonstrate the dynamics of changes in the territory, the description of the actors involved, and the affectations in the natural and social environment. We analyzed the vegetation change and urban growth from 1983 to 2014, incorporating climatic, edaphic, and topographic variables. A Principal Component Analysis was performed with the information and results were used in Maximum Likelihood procedure to define different clusters based on environmental characteristics. We defined five categories from the Landsat images. Results showed landscape units with homogeneous environmental characteristics and some differences in the units’ delineation were mainly influenced by political and socioeconomic factors. Temporally there was an increased tendency of landscape units, three in 1983, nine in 1990, 1995, 2000 and 2011, and eight in 2014. This increase resulted from territory fragmentation because of berries and avocado cultivars expansion over wooded area.

  15. An approach to delineate groundwater recharge potential sites in Ambalantota, Sri Lanka using GIS techniques

    Directory of Open Access Journals (Sweden)

    I.P. Senanayake

    2016-01-01

    Full Text Available The demand for fresh water in Hambantota District, Sri Lanka is rapidly increasing with the enormous amount of ongoing development projects in the region. Nevertheless, the district experiences periodic water stress conditions due to seasonal precipitation patterns and scarcity of surface water resources. Therefore, management of available groundwater resources is critical, to fulfil potable water requirements in the area. However, exploitation of groundwater should be carried out together with artificial recharging in order to maintain the long term sustainability of water resources. In this study, a GIS approach was used to delineate potential artificial recharge sites in Ambalantota area within Hambantota. Influential thematic layers such as rainfall, lineament, slope, drainage, land use/land cover, lithology, geomorphology and soil characteristics were integrated by using a weighted linear combination method. Results of the study reveal high to moderate groundwater recharge potential in approximately 49% of Ambalantota area.

  16. New Dilated LMI Characterization for the Multiobjective Full-Order Dynamic Output Feedback Synthesis Problem

    Directory of Open Access Journals (Sweden)

    Zrida Jalel

    2010-01-01

    Full Text Available This paper introduces new dilated LMI conditions for continuous-time linear systems which not only characterize stability and performance specifications, but also, performance specifications. These new conditions offer, in addition to new analysis tools, synthesis procedures that have the advantages of keeping the controller parameters independent of the Lyapunov matrix and offering supplementary degrees of freedom. The impact of such advantages is great on the multiobjective full-order dynamic output feedback control problem as the obtained dilated LMI conditions always encompass the standard ones. It follows that much less conservatism is possible in comparison to the currently used standard LMI based synthesis procedures. A numerical simulation, based on an empirically abridged search procedure, is presented and shows the advantage of the proposed synthesis methods.

  17. Heavy Metal Pollution Delineation Based on Uncertainty in a Coastal Industrial City in the Yangtze River Delta, China

    Directory of Open Access Journals (Sweden)

    Bifeng Hu

    2018-04-01

    Full Text Available Assessing heavy metal pollution and delineating pollution are the bases for evaluating pollution and determining a cost-effective remediation plan. Most existing studies are based on the spatial distribution of pollutants but ignore related uncertainty. In this study, eight heavy-metal concentrations (Cr, Pb, Cd, Hg, Zn, Cu, Ni, and Zn were collected at 1040 sampling sites in a coastal industrial city in the Yangtze River Delta, China. The single pollution index (PI and Nemerow integrated pollution index (NIPI were calculated for every surface sample (0–20 cm to assess the degree of heavy metal pollution. Ordinary kriging (OK was used to map the spatial distribution of heavy metals content and NIPI. Then, we delineated composite heavy metal contamination based on the uncertainty produced by indicator kriging (IK. The results showed that mean values of all PIs and NIPIs were at safe levels. Heavy metals were most accumulated in the central portion of the study area. Based on IK, the spatial probability of composite heavy metal pollution was computed. The probability of composite contamination in the central core urban area was highest. A probability of 0.6 was found as the optimum probability threshold to delineate polluted areas from unpolluted areas for integrative heavy metal contamination. Results of pollution delineation based on uncertainty showed the proportion of false negative error areas was 6.34%, while the proportion of false positive error areas was 0.86%. The accuracy of the classification was 92.80%. This indicated the method we developed is a valuable tool for delineating heavy metal pollution.

  18. Heavy Metal Pollution Delineation Based on Uncertainty in a Coastal Industrial City in the Yangtze River Delta, China.

    Science.gov (United States)

    Hu, Bifeng; Zhao, Ruiying; Chen, Songchao; Zhou, Yue; Jin, Bin; Li, Yan; Shi, Zhou

    2018-04-10

    Assessing heavy metal pollution and delineating pollution are the bases for evaluating pollution and determining a cost-effective remediation plan. Most existing studies are based on the spatial distribution of pollutants but ignore related uncertainty. In this study, eight heavy-metal concentrations (Cr, Pb, Cd, Hg, Zn, Cu, Ni, and Zn) were collected at 1040 sampling sites in a coastal industrial city in the Yangtze River Delta, China. The single pollution index (PI) and Nemerow integrated pollution index (NIPI) were calculated for every surface sample (0-20 cm) to assess the degree of heavy metal pollution. Ordinary kriging (OK) was used to map the spatial distribution of heavy metals content and NIPI. Then, we delineated composite heavy metal contamination based on the uncertainty produced by indicator kriging (IK). The results showed that mean values of all PIs and NIPIs were at safe levels. Heavy metals were most accumulated in the central portion of the study area. Based on IK, the spatial probability of composite heavy metal pollution was computed. The probability of composite contamination in the central core urban area was highest. A probability of 0.6 was found as the optimum probability threshold to delineate polluted areas from unpolluted areas for integrative heavy metal contamination. Results of pollution delineation based on uncertainty showed the proportion of false negative error areas was 6.34%, while the proportion of false positive error areas was 0.86%. The accuracy of the classification was 92.80%. This indicated the method we developed is a valuable tool for delineating heavy metal pollution.

  19. Heavy Metal Pollution Delineation Based on Uncertainty in a Coastal Industrial City in the Yangtze River Delta, China

    Science.gov (United States)

    Zhao, Ruiying; Chen, Songchao; Zhou, Yue; Jin, Bin; Li, Yan

    2018-01-01

    Assessing heavy metal pollution and delineating pollution are the bases for evaluating pollution and determining a cost-effective remediation plan. Most existing studies are based on the spatial distribution of pollutants but ignore related uncertainty. In this study, eight heavy-metal concentrations (Cr, Pb, Cd, Hg, Zn, Cu, Ni, and Zn) were collected at 1040 sampling sites in a coastal industrial city in the Yangtze River Delta, China. The single pollution index (PI) and Nemerow integrated pollution index (NIPI) were calculated for every surface sample (0–20 cm) to assess the degree of heavy metal pollution. Ordinary kriging (OK) was used to map the spatial distribution of heavy metals content and NIPI. Then, we delineated composite heavy metal contamination based on the uncertainty produced by indicator kriging (IK). The results showed that mean values of all PIs and NIPIs were at safe levels. Heavy metals were most accumulated in the central portion of the study area. Based on IK, the spatial probability of composite heavy metal pollution was computed. The probability of composite contamination in the central core urban area was highest. A probability of 0.6 was found as the optimum probability threshold to delineate polluted areas from unpolluted areas for integrative heavy metal contamination. Results of pollution delineation based on uncertainty showed the proportion of false negative error areas was 6.34%, while the proportion of false positive error areas was 0.86%. The accuracy of the classification was 92.80%. This indicated the method we developed is a valuable tool for delineating heavy metal pollution. PMID:29642623

  20. Basic problems and solution methods for two-dimensional continuous 3 × 3 order hidden Markov model

    International Nuclear Information System (INIS)

    Wang, Guo-gang; Tang, Gui-jin; Gan, Zong-liang; Cui, Zi-guan; Zhu, Xiu-chang

    2016-01-01

    A novel model referred to as two-dimensional continuous 3 × 3 order hidden Markov model is put forward to avoid the disadvantages of the classical hypothesis of two-dimensional continuous hidden Markov model. This paper presents three equivalent definitions of the model, in which the state transition probability relies on not only immediate horizontal and vertical states but also immediate diagonal state, and in which the probability density of the observation relies on not only current state but also immediate horizontal and vertical states. The paper focuses on the three basic problems of the model, namely probability density calculation, parameters estimation and path backtracking. Some algorithms solving the questions are theoretically derived, by exploiting the idea that the sequences of states on rows or columns of the model can be viewed as states of a one-dimensional continuous 1 × 2 order hidden Markov model. Simulation results further demonstrate the performance of the algorithms. Because there are more statistical characteristics in the structure of the proposed new model, it can more accurately describe some practical problems, as compared to two-dimensional continuous hidden Markov model.

  1. Delineation in thoracic oncology: a prospective study of the effect of training on contour variability and dosimetric consequences

    International Nuclear Information System (INIS)

    Dewas, Sylvain; Bibault, Jean-Emmanuel; Blanchard, Pierre; Vautravers-Dewas, Claire; Pointreau, Yoann; Denis, Fabrice; Brauner, Michel; Giraud, Philippe

    2011-01-01

    As part of French residents' radiotherapy training, delineation workstations were available at a national teaching course. We report a prospective comparative study of a non small cell lung cancer (NSCLC) case delineated by 120 residents before and after a radioanatomy/radiotherapy lecture. The case of a patient with right upper lobe non small cell lung cancer (NSCLC) was provided for delineation to 32 groups of residents before and after a radiation therapy lecture about thoracic delineation. GTV, CTV and PTV was asked to each group. In a second step, the GTV, CTV and PTV were compared with those of 9 groups of senior physicians. Finally the consequences for treatment planning between each group before and after the course were explored. The expert's average GTV, CTV and PTV were 89.1 cm 3 , 242.3 cm 3 and 293.9 cm 3 respectively. For residents, those volumes were 103.4 cm 3 , 242.3 cm 3 and 457.9 cm 3 before teaching, compared to 99.5 cm 3 , 224.2 cm 3 and 412.5 cm 3 after teaching. The overlap (OV) and kappa (KI) indices before and after education were respectively 0.58 and 0.73. Compared to senior physicians, OV and KI indices were lower in the residents group (p = 0.039 and p = 0.043). An increased dose to the lung is noted for the residents' dosimetry compared to the experts' (V20: 23.2% versus 36.5%) due to the larger PTV delineated. No significant difference was observed for other organs at risk. There were no significant differences for the delineation of the GTV and CTV before and after the course, although the differences tended to decrease after the course. The good initial quality of the contours could explain the lack of difference. V20 for lung was higher in the residents group compared to the experts group (23.2% vs 36.5%). No other treatment planning consequences were observed for other critical organs

  2. Delineation in thoracic oncology: a prospective study of the effect of training on contour variability and dosimetric consequences

    Directory of Open Access Journals (Sweden)

    Vautravers-Dewas Claire

    2011-09-01

    Full Text Available Abstract Introduction As part of French residents' radiotherapy training, delineation workstations were available at a national teaching course. We report a prospective comparative study of a non small cell lung cancer (NSCLC case delineated by 120 residents before and after a radioanatomy/radiotherapy lecture. Materials and methods The case of a patient with right upper lobe non small cell lung cancer (NSCLC was provided for delineation to 32 groups of residents before and after a radiation therapy lecture about thoracic delineation. GTV, CTV and PTV was asked to each group. In a second step, the GTV, CTV and PTV were compared with those of 9 groups of senior physicians. Finally the consequences for treatment planning between each group before and after the course were explored. Results The expert's average GTV, CTV and PTV were 89.1 cm3, 242.3 cm3 and 293.9 cm3 respectively. For residents, those volumes were 103.4 cm3, 242.3 cm3 and 457.9 cm3 before teaching, compared to 99.5 cm3, 224.2 cm3 and 412.5 cm3 after teaching. The overlap (OV and kappa (KI indices before and after education were respectively 0.58 and 0.73. Compared to senior physicians, OV and KI indices were lower in the residents group (p = 0.039 and p = 0.043. An increased dose to the lung is noted for the residents' dosimetry compared to the experts' (V20: 23.2% versus 36.5% due to the larger PTV delineated. No significant difference was observed for other organs at risk. Conclusion There were no significant differences for the delineation of the GTV and CTV before and after the course, although the differences tended to decrease after the course. The good initial quality of the contours could explain the lack of difference. V20 for lung was higher in the residents group compared to the experts group (23.2% vs 36.5%. No other treatment planning consequences were observed for other critical organs.

  3. Positive solutions of boundary value problem for singular positone and semi-positone third-order difference equations

    Directory of Open Access Journals (Sweden)

    Gai Gongqi

    2011-01-01

    Full Text Available Abstract This article studies the boundary value problems for the third-order nonlinear singular difference equations Δ 3 u ( i - 2 + λ a ( i f ( i , u ( i = 0 , i ∈ [ 2 , T + 2 ] , satisfying five kinds of different boundary value conditions. This article shows the existence of positive solutions for positone and semi-positone type. The nonlinear term may be singular. Two examples are also given to illustrate the main results. The arguments are based upon fixed point theorems in a cone. MSC [2008]: 34B15; 39A10.

  4. Combining project based learning with exercises in problem solving in order to train analytical mathematical skills

    DEFF Research Database (Denmark)

    Friesel, Anna

    2013-01-01

    This paper presents the contents and the teaching methods used in the fourth semester course - REG4E - an important subject in engineering, namely Control Theory and Dynamical Systems. Control Theory courses in engineering education are usually related to exercises in the laboratory or to projects....... However, in order to understand complexity of control systems, the students need to possess an analytical understanding of abstract mathematical problems. Our main goal is to illustrate the theory through the robot project, but at the same time we force our students to train their analytical skills...

  5. On a fourth order superlinear elliptic problem

    Directory of Open Access Journals (Sweden)

    M. Ramos

    2001-01-01

    Full Text Available We prove the existence of a nonzero solution for the fourth order elliptic equation $$Delta^2u= mu u +a(xg(u$$ with boundary conditions $u=Delta u=0$. Here, $mu$ is a real parameter, $g$ is superlinear both at zero and infinity and $a(x$ changes sign in $Omega$. The proof uses a variational argument based on the argument by Bahri-Lions cite{BL}.

  6. Photoproduction of the K= K0-(1750)

    International Nuclear Information System (INIS)

    Mitchell, Ryan Edward

    2003-01-01

    While photoproduction has often been advertised as an important environment in which to study light meson spectroscopy, solid experimental results are sparse. In fact, beyond the relatively straightforward photoproduction of the ρ, ω, and ψ mesons, the few results of exclusive photoproduction that do exist are poorly understood, and several, perhaps, have even been misinterpreted. After extensively reviewing the sometimes tenuous history of the exclusive photoproduction of the ''p'(1600),'' the ''ωπ 0 (1250),'' the ''ω(1650),'' and the ''K + K - (1750),'' new results from the E831/FOCUS photoproduction experiment at Fermilab are presented which address the interpretation of the K + K - (1750). This enhancement in low-p T K + K - pairs at a mass near 1750 MeV/c 2 has been observed by several previous photoproduction experiments, but, despite several apparent inconsistencies, it has always been interpreted as the J PC = 1 -- ψ(1680) meson. With nearly two orders of magnitude more events than any previous observation of the K + K - (1750), and based on precise measurements of its mass and width, and its absence from the K*K final state, the FOCUS data can finally render this interpretation implausible. In addition, several steps have been taken towards establishing a new interpretation. Based on limited angular analyses of its decay and the beam energy dependence of its production, they argue that, in the absence of any wild interference scenarios, the K + K - (1750) has J PC ≠ 1 -- , and, in fact, the most likely assignment appears to be 2 ++ . It is hoped that this work can help set the stage for future reevaluations and new insights in photoproduction

  7. Quality assessment of delineation and dose planning of early breast cancer patients included in the randomized Skagen Trial 1

    DEFF Research Database (Denmark)

    Francolini, Giulio; Thomsen, Mette S; Yates, Esben S

    2017-01-01

    , Dmax, D98%, D95% and D2%) from randomly selected dose plans were assessed. Target volume delineation according to ESTRO guidelines was obtained through atlas based automated segmentation and centrally approved as gold standard (GS). Dice similarity scores (DSC) with original delineations were measured....... No deviations in the dosimetric outcome were found in 76% of the patients, 82% and 95% of the patients had successful coverage of breast/chestwall and CTVn_L2-4-interpectoral. Dosimetric outcomes of original delineation and GS were comparable. CONCLUSIONS: QA showed high protocol compliance and adequate dose...... coverage in most patients. Inter-observer variability in contouring was low. Dose parameters were in harmony with protocol regardless original or GS segmentation....

  8. Internal and external validation of an ESTRO delineation guideline

    DEFF Research Database (Denmark)

    Eldesoky, Ahmed R.; Yates, Esben Svitzer; Nyeng, Tine B

    2016-01-01

    Background and purpose To internally and externally validate an atlas based automated segmentation (ABAS) in loco-regional radiation therapy of breast cancer. Materials and methods Structures of 60 patients delineated according to the ESTRO consensus guideline were included in four categorized...... and axillary nodal levels and poor agreement for interpectoral, internal mammary nodal regions and LADCA. Correcting ABAS significantly improved all the results. External validation of ABAS showed comparable results. Conclusions ABAS is a clinically useful tool for segmenting structures in breast cancer loco...

  9. A teaching intervention in a contouring dummy run improved target volume delineation in locally advanced non-small cell lung cancer: Reducing the interobserver variability in multicentre clinical studies.

    Science.gov (United States)

    Schimek-Jasch, Tanja; Troost, Esther G C; Rücker, Gerta; Prokic, Vesna; Avlar, Melanie; Duncker-Rohr, Viola; Mix, Michael; Doll, Christian; Grosu, Anca-Ligia; Nestle, Ursula

    2015-06-01

    Interobserver variability in the definition of target volumes (TVs) is a well-known confounding factor in (multicentre) clinical studies employing radiotherapy. Therefore, detailed contouring guidelines are provided in the prospective randomised multicentre PET-Plan (NCT00697333) clinical trial protocol. This trial compares strictly FDG-PET-based TV delineation with conventional TV delineation in patients with locally advanced non-small cell lung cancer (NSCLC). Despite detailed contouring guidelines, their interpretation by different radiation oncologists can vary considerably, leading to undesirable discrepancies in TV delineation. Considering this, as part of the PET-Plan study quality assurance (QA), a contouring dummy run (DR) consisting of two phases was performed to analyse the interobserver variability before and after teaching. In the first phase of the DR (DR1), radiation oncologists from 14 study centres were asked to delineate TVs as defined by the study protocol (gross TV, GTV; and two clinical TVs, CTV-A and CTV-B) in a test patient. A teaching session was held at a study group meeting, including a discussion of the results focussing on discordances in comparison to the per-protocol solution. Subsequently, the second phase of the DR (DR2) was performed in order to evaluate the impact of teaching. Teaching after DR1 resulted in a reduction of absolute TVs in DR2, as well as in better concordance of TVs. The Overall Kappa(κ) indices increased from 0.63 to 0.71 (GTV), 0.60 to 0.65 (CTV-A) and from 0.59 to 0.63 (CTV-B), demonstrating improvements in overall interobserver agreement. Contouring DRs and study group meetings as part of QA in multicentre clinical trials help to identify misinterpretations of per-protocol TV delineation. Teaching the correct interpretation of protocol contouring guidelines leads to a reduction in interobserver variability and to more consistent contouring, which should consequently improve the validity of the overall study

  10. A teaching intervention in a contouring dummy run improved target volume delineation in locally advanced non-small cell lung cancer. Reducing the interobserver variability in multicentre clinical studies

    International Nuclear Information System (INIS)

    Schimek-Jasch, Tanja; Prokic, Vesna; Doll, Christian; Grosu, Anca-Ligia; Nestle, Ursula; Troost, Esther G.C.; Ruecker, Gerta; Avlar, Melanie; Duncker-Rohr, Viola; Mix, Michael

    2015-01-01

    Interobserver variability in the definition of target volumes (TVs) is a well-known confounding factor in (multicentre) clinical studies employing radiotherapy. Therefore, detailed contouring guidelines are provided in the prospective randomised multicentre PET-Plan (NCT00697333) clinical trial protocol. This trial compares strictly FDG-PET-based TV delineation with conventional TV delineation in patients with locally advanced non-small cell lung cancer (NSCLC). Despite detailed contouring guidelines, their interpretation by different radiation oncologists can vary considerably, leading to undesirable discrepancies in TV delineation. Considering this, as part of the PET-Plan study quality assurance (QA), a contouring dummy run (DR) consisting of two phases was performed to analyse the interobserver variability before and after teaching. In the first phase of the DR (DR1), radiation oncologists from 14 study centres were asked to delineate TVs as defined by the study protocol (gross TV, GTV; and two clinical TVs, CTV-A and CTV-B) in a test patient. A teaching session was held at a study group meeting, including a discussion of the results focussing on discordances in comparison to the per-protocol solution. Subsequently, the second phase of the DR (DR2) was performed in order to evaluate the impact of teaching. Teaching after DR1 resulted in a reduction of absolute TVs in DR2, as well as in better concordance of TVs. The Overall Kappa(κ) indices increased from 0.63 to 0.71 (GTV), 0.60 to 0.65 (CTV-A) and from 0.59 to 0.63 (CTV-B), demonstrating improvements in overall interobserver agreement. Contouring DRs and study group meetings as part of QA in multicentre clinical trials help to identify misinterpretations of per-protocol TV delineation. Teaching the correct interpretation of protocol contouring guidelines leads to a reduction in interobserver variability and to more consistent contouring, which should consequently improve the validity of the overall study

  11. Higher Order Thinking Skills as Effect of Problem Based Learning in the 21st Century Learning

    Directory of Open Access Journals (Sweden)

    Leni Widiawati

    2018-03-01

    Full Text Available This study aims to determine the responses of learners to learning using a scientific approach in Problem Based Learning integrated with the inculcation of critical thinking, communicative, collaboration; and creative (4C skills in 21st century learning. The design of this study is true experiment by using posttest only control design. The sample of the research is vocational school students selected by using cluster random sampling technique in Surakarta, Indonesia. The techniques of collecting data are using tests whose validity, reliability, level of difficulty, and the discrimination index have been tested. The data obtained are then tested using t test. The result of the research shows that higher order thinking skills of experimental class students learning using scientific approach in Problem Based Learning which is integrated with the inculcation of 4C skills are higher than those of the control class that are learning using scientific approach in Think-Pair-Share which is integrated with the inculcation of 4C skills.

  12. Improving superficial target delineation in radiation therapy with endoscopic tracking and registration

    Energy Technology Data Exchange (ETDEWEB)

    Weersink, R. A.; Qiu, J.; Hope, A. J.; Daly, M. J.; Cho, B. C. J.; DaCosta, R. S.; Sharpe, M. B.; Breen, S. L.; Chan, H.; Jaffray, D. A. [Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada) and Ontario Cancer Institute, University Health Network, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada) and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9, Canada and Ontario Cancer Institute, University Health Network, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada) and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5G 2M9 (Canada) and Ontario Cancer Institute, University Health Network, Toronto, Ontario M5G 2M9 (Canada)

    2011-12-15

    Purpose: Target delineation within volumetric imaging is a critical step in the planning process of intensity modulated radiation therapy. In endoluminal cancers, endoscopy often reveals superficial areas of visible disease beyond what is seen on volumetric imaging. Quantitatively relating these findings to the volumetric imaging is prone to human error during the recall and contouring of the target. We have developed a method to improve target delineation in the radiation therapy planning process by quantitatively registering endoscopic findings contours traced on endoscopic images to volumetric imaging. Methods: Using electromagnetic sensors embedded in an endoscope, 2D endoscopic images were registered to computed tomography (CT) volumetric images by tracking the position and orientation of the endoscope relative to a CT image set. Regions-of-interest (ROI) in the 2D endoscopic view were delineated. A mesh created within the boundary of the ROI was projected onto the 3D image data, registering the ROI with the volumetric image. This 3D ROI was exported to clinical radiation treatment planning software. The precision and accuracy of the procedure was tested on two solid phantoms with superficial markings visible on both endoscopy and CT images. The first phantom was T-shaped tube with X-marks etched on the interior. The second phantom was an anatomically correct skull phantom with a phantom superficial lesion placed on the pharyngeal surface. Markings were contoured on the endoscope images and compared with contours delineated in the treatment planning system based on the CT images. Clinical feasibility was tested on three patients with early stage glottic cancer. Image-based rendering using manually identified landmarks was used to improve the registration. Results: Using the T-shaped phantom with X-markings, the 2D to 3D registration accuracy was 1.5-3.5 mm, depending on the endoscope position relative to the markings. Intraobserver standard variation was 0

  13. The depression of a graph and k-kernels

    Directory of Open Access Journals (Sweden)

    Schurch Mark

    2014-05-01

    Full Text Available An edge ordering of a graph G is an injection f : E(G → R, the set of real numbers. A path in G for which the edge ordering f increases along its edge sequence is called an f-ascent ; an f-ascent is maximal if it is not contained in a longer f-ascent. The depression of G is the smallest integer k such that any edge ordering f has a maximal f-ascent of length at most k. A k-kernel of a graph G is a set of vertices U ⊆ V (G such that for any edge ordering f of G there exists a maximal f-ascent of length at most k which neither starts nor ends in U. Identifying a k-kernel of a graph G enables one to construct an infinite family of graphs from G which have depression at most k. We discuss various results related to the concept of k-kernels, including an improved upper bound for the depression of trees.

  14. Target Volume Delineation in Oropharyngeal Cancer: Impact of PET, MRI, and Physical Examination

    International Nuclear Information System (INIS)

    Thiagarajan, Anuradha; Caria, Nicola; Schöder, Heiko; Iyer, N. Gopalakrishna; Wolden, Suzanne; Wong, Richard J.; Sherman, Eric; Fury, Matthew G.; Lee, Nancy

    2012-01-01

    Introduction: Sole utilization of computed tomography (CT) scans in gross tumor volume (GTV) delineation for head-and-neck cancers is subject to inaccuracies. This study aims to evaluate contributions of magnetic resonance imaging (MRI), positron emission tomography (PET), and physical examination (PE) to GTV delineation in oropharyngeal cancer (OPC). Methods: Forty-one patients with OPC were studied. All underwent contrast-enhanced CT simulation scans (CECTs) that were registered with pretreatment PETs and MRIs. For each patient, three sets of primary and nodal GTV were contoured. First, reference GTVs (GTVref) were contoured by the treating radiation oncologist (RO) using CT, MRI, PET, and PE findings. Additional GTVs were created using fused CT/PET scans (GTVctpet) and CT/MRI scans (GTVctmr) by two other ROs blinded to GTVref. To compare GTVs, concordance indices (CI) were calculated by dividing the respective overlap volumes by overall volumes. To evaluate the contribution of PE, composite GTVs derived from CT, MRI, and PET (GTVctpetmr) were compared with GTVref. Results: For primary tumors, GTVref was significantly larger than GTVctpet and GTVctmr (p 0.75), indicating that although the modalities were complementary, the added benefit was small in the context of CECTs. In addition, PE did not aid greatly in nodal GTV delineation. Conclusion: PET and MRI are complementary and combined use is ideal. However, the low CI (ctpetmr vs. ref) particularly for primary tumors underscores the limitations of defining GTVs using imaging alone. PE is invaluable and must be incorporated.

  15. Instructor Strategic Ambiguity: Delineation of the Construct and Development of a Measure

    Science.gov (United States)

    Klyukovski, Andrei A.; Medlock-Klyukovski, Amanda L.

    2016-01-01

    This article presents research to delineate the construct of instructor strategic ambiguity (ISA) and develop a measure. The first study analyzed instructor uses of ambiguity, identified 18 strategies, and classified them into four categories. The second study developed an Instructor Strategic Ambiguity Measure (ISAM) for the college classroom.…

  16. The second-order S-matrix element for the elastic scattering of photons by K-shell bound electrons: the nonrelativistic limit

    Energy Technology Data Exchange (ETDEWEB)

    Costescu, A [Department of Physics, University of Bucharest, MG11, Bucharest-Magurele 76900 (Romania); Spanulescu, S [Department of Physics, University of Bucharest, MG11, Bucharest-Magurele 76900 (Romania); Stoica, C [Department of Physics, University of Bucharest, MG11, Bucharest-Magurele 76900 (Romania)

    2007-08-14

    The right expressions of the nonrelativistic K-shell Rayleigh scattering amplitudes and cross-sections are obtained by using the Coulomb Green's function method. Our analytical result does not have the spurious poles that occur in the old nonrelativistic result with retardation (Gavrila and Costescu 1970 Phys. Rev. A 2 1752). Starting from the expression of the second-order S-matrix element for the case of the elastic scattering of photons by K-shell bound electrons, we obtain the correct nonrelativistic Rayleigh angular distribution (valid for photon energies {omega} up to {alpha}Zm) by removing the relativistic higher order terms in {alpha}Z and {omega}/m. The imaginary part of the Rayleigh amplitudes is obtained for any scattering angles in a closed form in terms of elementary functions. Thereby a simple formula for the exact nonrelativistic photoeffect total cross-section is obtained via the optical theorem, giving significantly better predictions than Fischer's nonrelativistic photoeffect formula. Comparing the predictions given by our formulae with the full relativistic numerical calculations of Kissel et al (Phys. Rev. 1980 A 22 1970), and with experimental results, a fairly good agreement within 10% is found for the angular distribution of Rayleigh scattering for photon energies up to 200 keV and both below and above the first resonance.

  17. Detection and delineation of waste trenches by geophysical methods at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Selfridge, R.J.

    1987-01-01

    Detection and delineation of waste trenches at hazardous waste sites are needed before actual implementation of site corrective measures. In a field study conducted in Solid Waste Storage Area 4 (SWSA4) at Oak Ridge National Laboratory (ORNL), surface geophysical techniques were used to assist in the delineation of waste trenches. A magnetometer/gradiometer survey was used to detect ferrous metals buried at the site. An electromagnetic ground conductivity survey was used to measure the electrical conductivity of the subsurface and aided in supporting the magnetometer/gradiometer results. Results from the two techniques were complimentary and easily integrated into a final interpretation. The reliability, efficiency, and worker safety benefits of these techniques offer a nondestructive surface technique for locating buried waste trenches

  18. Appreciation of learning environment and development of higher-order learning skills in a problem-based learning medical curriculum.

    Science.gov (United States)

    Mala-Maung; Abdullah, Azman; Abas, Zoraini W

    2011-12-01

    This cross-sectional study determined the appreciation of the learning environment and development of higher-order learning skills among students attending the Medical Curriculum at the International Medical University, Malaysia which provides traditional and e-learning resources with an emphasis on problem based learning (PBL) and self-directed learning. Of the 708 participants, the majority preferred traditional to e-resources. Students who highly appreciated PBL demonstrated a higher appreciation of e-resources. Appreciation of PBL is positively and significantly correlated with higher-order learning skills, reflecting the inculcation of self-directed learning traits. Implementers must be sensitive to the progress of learners adapting to the higher education environment and innovations, and to address limitations as relevant.

  19. Numerical Solutions of Fifth Order Boundary Value Problems Using

    African Journals Online (AJOL)

    Dr A.B.Ahmed

    1Department of Mathematics Delta State University, Abraka, Nigeria. 2Department of ..... International Journal of Computational. Mathematics and ... Value Problems using Power Series Approximation Method.Applied. Mathematics,. 7,. 1215-.

  20. Bayesian linkage and segregation analysis: factoring the problem.

    Science.gov (United States)

    Matthysse, S

    2000-01-01

    Complex segregation analysis and linkage methods are mathematical techniques for the genetic dissection of complex diseases. They are used to delineate complex modes of familial transmission and to localize putative disease susceptibility loci to specific chromosomal locations. The computational problem of Bayesian linkage and segregation analysis is one of integration in high-dimensional spaces. In this paper, three available techniques for Bayesian linkage and segregation analysis are discussed: Markov Chain Monte Carlo (MCMC), importance sampling, and exact calculation. The contribution of each to the overall integration will be explicitly discussed.