WorldWideScience

Sample records for local approach methods

  1. An Efficient Local Correlation Matrix Decomposition Approach for the Localization Implementation of Ensemble-Based Assimilation Methods

    Science.gov (United States)

    Zhang, Hongqin; Tian, Xiangjun

    2018-04-01

    Ensemble-based data assimilation methods often use the so-called localization scheme to improve the representation of the ensemble background error covariance (Be). Extensive research has been undertaken to reduce the computational cost of these methods by using the localized ensemble samples to localize Be by means of a direct decomposition of the local correlation matrix C. However, the computational costs of the direct decomposition of the local correlation matrix C are still extremely high due to its high dimension. In this paper, we propose an efficient local correlation matrix decomposition approach based on the concept of alternating directions. This approach is intended to avoid direct decomposition of the correlation matrix. Instead, we first decompose the correlation matrix into 1-D correlation matrices in the three coordinate directions, then construct their empirical orthogonal function decomposition at low resolution. This procedure is followed by the 1-D spline interpolation process to transform the above decompositions to the high-resolution grid. Finally, an efficient correlation matrix decomposition is achieved by computing the very similar Kronecker product. We conducted a series of comparison experiments to illustrate the validity and accuracy of the proposed local correlation matrix decomposition approach. The effectiveness of the proposed correlation matrix decomposition approach and its efficient localization implementation of the nonlinear least-squares four-dimensional variational assimilation are further demonstrated by several groups of numerical experiments based on the Advanced Research Weather Research and Forecasting model.

  2. Damage approach: A new method for topology optimization with local stress constraints

    DEFF Research Database (Denmark)

    Verbart, Alexander; Langelaar, Matthijs; van Keulen, Fred

    2016-01-01

    In this paper, we propose a new method for topology optimization with local stress constraints. In this method, material in which a stress constraint is violated is considered as damaged. Since damaged material will contribute less to the overall performance of the structure, the optimizer...... will promote a design with a minimal amount of damaged material. We tested the method on several benchmark problems, and the results show that the method is a viable alternative for conventional stress-based approaches based on constraint relaxation followed by constraint aggregation....

  3. Local Stakeholder Perception on Community Participation in Marine Protected Area Management: A Q-Method Approach

    Science.gov (United States)

    Megat Jamual Fawaeed, P. S.; Daim, M. S.

    2018-02-01

    Local stakeholder involvement in Marine Protected Area (MPA) management can bring to a successful MPA. Generally, participatory research in marine protected area management is exploring the relationship between marine protected area management approach adopted by the management agencies and the level of participation of local stakeholder whom reside within the marine protected areas. However, the scenario of local community participation in MPA management in Malaysia seems discouraging and does not align with the International Aichi Biodiversity Target 2020. In order to achieve the International Aichi Biodiversity Target 2020, this paper attempts to explore the methodology on participatory research towards the local stakeholder of Pulau Perhentian Marine Park (PPMP), Terengganu, Malaysia. A Q-methodology is used to investigate the perspective of local stakeholder who represents different stances on the issues, by having participants rank and sort a series of statements by comply quantitative and qualitative method in collecting the data. A structured questionnaire will be employed across this study by means of face-to-face interview. In total, 210 respondents from Kampung Pasir Hantu are randomly selected. Meanwhile, a workshop with the agency (Department of Marine Park) had been held to discuss about the issues faces on behalf of management that manage the PPMP. Using the Q-method, researcher acknowledged wise viewpoints, reflecting how different stakeholders’ perception and opinion about community participation with highlights the current level of community participation in MPA. Thus, this paper describes the phases involved in this study, methodology and analysis used in making a conclusion .

  4. Mode decomposition methods for flows in high-contrast porous media. Global-local approach

    KAUST Repository

    Ghommem, Mehdi; Presho, Michael; Calo, Victor M.; Efendiev, Yalchin R.

    2013-01-01

    In this paper, we combine concepts of the generalized multiscale finite element method (GMsFEM) and mode decomposition methods to construct a robust global-local approach for model reduction of flows in high-contrast porous media. This is achieved by implementing Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD) techniques on a coarse grid computed using GMsFEM. The resulting reduced-order approach enables a significant reduction in the flow problem size while accurately capturing the behavior of fully-resolved solutions. We consider a variety of high-contrast coefficients and present the corresponding numerical results to illustrate the effectiveness of the proposed technique. This paper is a continuation of our work presented in Ghommem et al. (2013) [1] where we examine the applicability of POD and DMD to derive simplified and reliable representations of flows in high-contrast porous media on fully resolved models. In the current paper, we discuss how these global model reduction approaches can be combined with local techniques to speed-up the simulations. The speed-up is due to inexpensive, while sufficiently accurate, computations of global snapshots. © 2013 Elsevier Inc.

  5. Mode decomposition methods for flows in high-contrast porous media. Global-local approach

    KAUST Repository

    Ghommem, Mehdi

    2013-11-01

    In this paper, we combine concepts of the generalized multiscale finite element method (GMsFEM) and mode decomposition methods to construct a robust global-local approach for model reduction of flows in high-contrast porous media. This is achieved by implementing Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD) techniques on a coarse grid computed using GMsFEM. The resulting reduced-order approach enables a significant reduction in the flow problem size while accurately capturing the behavior of fully-resolved solutions. We consider a variety of high-contrast coefficients and present the corresponding numerical results to illustrate the effectiveness of the proposed technique. This paper is a continuation of our work presented in Ghommem et al. (2013) [1] where we examine the applicability of POD and DMD to derive simplified and reliable representations of flows in high-contrast porous media on fully resolved models. In the current paper, we discuss how these global model reduction approaches can be combined with local techniques to speed-up the simulations. The speed-up is due to inexpensive, while sufficiently accurate, computations of global snapshots. © 2013 Elsevier Inc.

  6. A nonparametric approach to calculate critical micelle concentrations: the local polynomial regression method

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Fontan, J.L.; Costa, J.; Ruso, J.M.; Prieto, G. [Dept. of Applied Physics, Univ. of Santiago de Compostela, Santiago de Compostela (Spain); Sarmiento, F. [Dept. of Mathematics, Faculty of Informatics, Univ. of A Coruna, A Coruna (Spain)

    2004-02-01

    The application of a statistical method, the local polynomial regression method, (LPRM), based on a nonparametric estimation of the regression function to determine the critical micelle concentration (cmc) is presented. The method is extremely flexible because it does not impose any parametric model on the subjacent structure of the data but rather allows the data to speak for themselves. Good concordance of cmc values with those obtained by other methods was found for systems in which the variation of a measured physical property with concentration showed an abrupt change. When this variation was slow, discrepancies between the values obtained by LPRM and others methods were found. (orig.)

  7. A Discrete Element Method Approach to Progressive Localization of Damage in Granular Rocks and Associated Seismicity

    Science.gov (United States)

    Vora, H.; Morgan, J.

    2017-12-01

    Brittle failure in rock under confined biaxial conditions is accompanied by release of seismic energy, known as acoustic emissions (AE). The objective our study is to understand the influence of elastic properties of rock and its stress state on deformation patterns, and associated seismicity in granular rocks. Discrete Element Modeling is used to simulate biaxial tests on granular rocks of defined grain size distribution. Acoustic Energy and seismic moments are calculated from microfracture events as rock is taken to conditions of failure under different confining pressure states. Dimensionless parameters such as seismic b-value and fractal parameter for deformation, D-value, are used to quantify seismic character and distribution of damage in rock. Initial results suggest that confining pressure has the largest control on distribution of induced microfracturing, while fracture energy and seismic magnitudes are highly sensitive to elastic properties of rock. At low confining pressures, localized deformation (low D-values) and high seismic b-values are observed. Deformation at high confining pressures is distributed in nature (high D-values) and exhibit low seismic b-values as shearing becomes the dominant mode of microfracturing. Seismic b-values and fractal D-values obtained from microfracturing exhibit a linear inverse relationship, similar to trends observed in earthquakes. Mode of microfracturing in our simulations of biaxial compression tests show mechanistic similarities to propagation of fractures and faults in nature.

  8. Efficient and accurate local approximations to coupled-electron pair approaches: An attempt to revive the pair natural orbital method.

    Science.gov (United States)

    Neese, Frank; Wennmohs, Frank; Hansen, Andreas

    2009-03-21

    Coupled-electron pair approximations (CEPAs) and coupled-pair functionals (CPFs) have been popular in the 1970s and 1980s and have yielded excellent results for small molecules. Recently, interest in CEPA and CPF methods has been renewed. It has been shown that these methods lead to competitive thermochemical, kinetic, and structural predictions. They greatly surpass second order Moller-Plesset and popular density functional theory based approaches in accuracy and are intermediate in quality between CCSD and CCSD(T) in extended benchmark studies. In this work an efficient production level implementation of the closed shell CEPA and CPF methods is reported that can be applied to medium sized molecules in the range of 50-100 atoms and up to about 2000 basis functions. The internal space is spanned by localized internal orbitals. The external space is greatly compressed through the method of pair natural orbitals (PNOs) that was also introduced by the pioneers of the CEPA approaches. Our implementation also makes extended use of density fitting (or resolution of the identity) techniques in order to speed up the laborious integral transformations. The method is called local pair natural orbital CEPA (LPNO-CEPA) (LPNO-CPF). The implementation is centered around the concepts of electron pairs and matrix operations. Altogether three cutoff parameters are introduced that control the size of the significant pair list, the average number of PNOs per electron pair, and the number of contributing basis functions per PNO. With the conservatively chosen default values of these thresholds, the method recovers about 99.8% of the canonical correlation energy. This translates to absolute deviations from the canonical result of only a few kcal mol(-1). Extended numerical test calculations demonstrate that LPNO-CEPA (LPNO-CPF) has essentially the same accuracy as parent CEPA (CPF) methods for thermochemistry, kinetics, weak interactions, and potential energy surfaces but is up to 500

  9. Enzyme-labeled Antigen Method: Development and Application of the Novel Approach for Identifying Plasma Cells Locally Producing Disease-specific Antibodies in Inflammatory Lesions

    International Nuclear Information System (INIS)

    Mizutani, Yasuyoshi; Shiogama, Kazuya; Onouchi, Takanori; Sakurai, Kouhei; Inada, Ken-ichi; Tsutsumi, Yutaka

    2016-01-01

    In chronic inflammatory lesions of autoimmune and infectious diseases, plasma cells are frequently observed. Antigens recognized by antibodies produced by the plasma cells mostly remain unclear. A new technique identifying these corresponding antigens may give us a breakthrough for understanding the disease from a pathophysiological viewpoint, simply because the immunocytes are seen within the lesion. We have developed an enzyme-labeled antigen method for microscopic identification of the antigen recognized by specific antibodies locally produced in plasma cells in inflammatory lesions. Firstly, target biotinylated antigens were constructed by the wheat germ cell-free protein synthesis system or through chemical biotinylation. Next, proteins reactive to antibodies in tissue extracts were screened and antibody titers were evaluated by the AlphaScreen method. Finally, with the enzyme-labeled antigen method using the biotinylated antigens as probes, plasma cells producing specific antibodies were microscopically localized in fixed frozen sections. Our novel approach visualized tissue plasma cells that produced 1) autoantibodies in rheumatoid arthritis, 2) antibodies against major antigens of Porphyromonas gingivalis in periodontitis or radicular cyst, and 3) antibodies against a carbohydrate antigen, Strep A, of Streptococcus pyogenes in recurrent tonsillitis. Evaluation of local specific antibody responses expectedly contributes to clarifying previously unknown processes in inflammatory disorders

  10. Determinants of eating at local and western fast-food venues in an urban Asian population: a mixed methods approach.

    Science.gov (United States)

    Naidoo, Nasheen; van Dam, Rob M; Ng, Sheryl; Tan, Chuen Seng; Chen, Shiqi; Lim, Jia Yi; Chan, Mei Fen; Chew, Ling; Rebello, Salome A

    2017-05-25

    Like several Southeast Asian countries, Singapore has a complex eating-out environment and a rising eating-out prevalence. However the determinants and drivers of eating-out in urban Asian environments are poorly understood. We examined the socio-demographic characteristics of persons who frequently ate away from home in local eateries called hawker centres and Western fast-food restaurants, using data from 1647 Singaporean adults participating in the National Nutrition Survey (NNS) 2010. We also assessed the underlying drivers of eating out and evaluated if these were different for eating at local eateries compared to Western fast-food restaurants using 18 focus group discussions of women (130 women). Participants reported a high eating-out frequency with 77.3% usually eating either breakfast, lunch or dinner at eateries. Main venues for eating-out included hawker centres (61.1% usually ate at least 1 of 3 daily meals at this venue) and school/workplace canteens (20.4%). A minority of participants (1.9%) reported usually eating at Western fast-food restaurants. Younger participants and those of Chinese and Malay ethnicity compared to Indians were more likely to eat at Western fast-food restaurants. Chinese and employed persons were more likely to eat at hawker centres. The ready availability of a large variety of affordable and appealing foods appeared to be a primary driver of eating out, particularly at hawker centres. Our findings highlight the growing importance of eating-out in an urban Asian population where local eating venues play a more dominant role compared with Western fast-food chains. Interventions focusing on improving the food quality at venues for eating out are important to improve the diet of urban Asian populations.

  11. Design local exhaust ventilation on sieve machine at PT.Perkebunan Nusantara VIII Ciater using design for assembly (DFA) approach with Boothroyd and Dewhurst method

    Science.gov (United States)

    Khalqihi, K. I.; Rahayu, M.; Rendra, M.

    2017-12-01

    PT Perkebunan Nusantara VIII Ciater is a company produced black tea orthodox more or less 4 tons every day. At the production section, PT Perkebunan Nusantara VIII will use local exhaust ventilation specially at sortation area on sieve machine. To maintain the quality of the black tea orthodox, all machine must be scheduled for maintenance every once a month and takes time 2 hours in workhours, with additional local exhaust ventilation, it will increase time for maintenance process, if maintenance takes time more than 2 hours it will caused production process delayed. To support maintenance process in PT Perkebunan Nusantara VIII Ciater, designing local exhaust ventilation using design for assembly approach with Boothroyd and Dewhurst method, design for assembly approach is choosen to simplify maintenance process which required assembly process. There are 2 LEV designs for this research. Design 1 with 94 components, assembly time 647.88 seconds and assembly efficiency level 23.62%. Design 2 with 82 components, assembly time 567.84 seconds and assembly efficiency level 24.83%. Design 2 is choosen for this research based on DFA goals, minimum total part that use, optimization assembly time, and assembly efficiency level.

  12. [Classification of local anesthesia methods].

    Science.gov (United States)

    Petricas, A Zh; Medvedev, D V; Olkhovskaya, E B

    The traditional classification methods of dental local anesthesia must be modified. In this paper we proved that the vascular mechanism is leading component of spongy injection. It is necessary to take into account the high effectiveness and relative safety of spongy anesthesia, as well as versatility, ease of implementation and the growing prevalence in the world. The essence of the proposed modification is to distinguish the methods in diffusive (including surface anesthesia, infiltration and conductive anesthesia) and vascular-diffusive (including intraosseous, intraligamentary, intraseptal and intrapulpal anesthesia). For the last four methods the common term «spongy (intraosseous) anesthesia» may be used.

  13. Design approach to local blockages

    International Nuclear Information System (INIS)

    Roychowdhury, D.G.; Govindarajan, S.; Chetal, S.C.; Bhoje, S.B.

    2000-01-01

    In LMFBR, whole core meltdown accident falls in residual risk category. Propagation of a local fault to whole core, however, needs attention. Subassembly accidents are divided into two categories, Design Basis and Beyond Design Basis accidents. Design Basis is further classified into four categories. All events affecting fuel pin performance are identified and categorised, Total Instantaneous Blockage has been identified as the envelope of all local faults and categorised as BDB event and the safety objective is to demonstrate that no damage will propagate beyond six neighbouring SA. A core catcher has been provided for retention of core debris and cooling it by natural convection. Local blockages may be active and passive. Active blockages can be detected by DND signal. For passive blockages, detection is difficult. Hence, development of a finite volume computer code based on the porous body formulation has been undertaken to define the maximum allowable defect. Experimental programmes have been undertaken to understand blockage mechanism, define maximum credible defect and the thermalhydraulic behaviour of SA with local blockages. Also an experimental programme with a totally blocked SA with a bundle of heated pins has been undertaken to understand the behaviour of the SA. (author)

  14. Local farmers' approach to soil conservation: Lessons from Nigeria ...

    African Journals Online (AJOL)

    This paper explores the indigenous knowledge systems (IKS) approaches to soil conservation in Nigeria. It specifically identifies various indigenous/local and modern methods employed in the process of utilizing an integrated approach to soil conservation by all stakeholders (local farmers, governmental and ...

  15. Local defect correction for boundary integral equation methods

    NARCIS (Netherlands)

    Kakuba, G.; Anthonissen, M.J.H.

    2014-01-01

    The aim in this paper is to develop a new local defect correction approach to gridding for problems with localised regions of high activity in the boundary element method. The technique of local defect correction has been studied for other methods as finite difference methods and finite volume

  16. Approach of simultaneous localization and mapping based on local maps for robot

    Institute of Scientific and Technical Information of China (English)

    CHEN Bai-fan; CAI Zi-xing; HU De-wen

    2006-01-01

    An extended Kalman filter approach of simultaneous localization and mapping(SLAM) was proposed based on local maps.A local frame of reference was established periodically at the position of the robot, and then the observations of the robot and landmarks were fused into the global frame of reference. Because of the independence of the local map, the approach does not cumulate the estimate and calculation errors which are produced by SLAM using Kalman filter directly. At the same time, it reduces the computational complexity. This method is proven correct and feasible in simulation experiments.

  17. Localized Multiple Kernel Learning A Convex Approach

    Science.gov (United States)

    2016-11-22

    data. All the aforementioned approaches to localized MKL are formulated in terms of non-convex optimization problems, and deep the- oretical...learning. IEEE Transactions on Neural Networks, 22(3):433–446, 2011. Jingjing Yang, Yuanning Li, Yonghong Tian, Lingyu Duan, and Wen Gao. Group-sensitive

  18. Experimental and numerical investigations on the applicability of local approach methods on the warm prestress effect; Experimentelle und numerische Untersuchungen zur Anwendbarkeit von Local-Approach-Ansaetzen auf WPS-Effekt

    Energy Technology Data Exchange (ETDEWEB)

    Roos, E; Elsaesser, K [Stuttgart Univ. (Germany). Staatliche Materialpruefungsanstalt

    1998-11-01

    The three materials 10 MnMoNi 5 5, as a welded specimen, 22 NiMoCr 3 7 mod., and 17 MoV 8 4 mod. have been examined as a part of project work. The major known influencing variables with respect to the WPS effect are materials hardening, crack tip blunting, and the developing residual stress field. The project task was to investigate to what extent the finite element method will be able to describe these influencing variables. Using the damaging model of Rousselier it is possible to simulate the processes during warm prestressing at upper-shelf toughness while taking into account the crack growth. Using the parameter derived with the Beremin model with notched specimens and applying these to pre-cracked specimens will not yield accurate results describing the fracture toughness in the area affected by embrittlement. (orig./CB) [Deutsch] Im Rahmen des Forschungsprojektes wurden die drei Werkstoffe 10 MnMoNi 5 5 formgeschweisst, 22 NiMoCr 3 7 mod. und 17 MoV 8 4 mod. untersucht. Als hauptsaechliche Einflussgroessen fuer den WPS-Effekt gelten die Werkstoffverfestigung, die Abstumpfung der Rissspitze (Blunting), sowie das sich ausbildende Eigenspannungsfeld. Es wurde untersucht, inwieweit es mit Hilfe der Methode der Finiten Elemente moeglich ist, die einzelnen Einflussgroessen zu beschreiben. Mit Hilfe des Schaedigungsmodelles von Rousselier koennen die Vorgaenge beim Warmvorbelasten in der Zaehigkeitshochlage auch unter Beruecksichtigung von Risswachstum simuliert werden. Bei Verwendung der an gekerbten Proben ermittelten Parameter des Beremin-Modelles und deren Uebertragung auf angerissene Proben wird die Bruchzaehigkeit im Sproedbruchgebiet nicht zutreffend berechnet. (orig./MM)

  19. Decentralized Cooperative Localization Approach for Autonomous Multirobot Systems

    Directory of Open Access Journals (Sweden)

    Thumeera R. Wanasinghe

    2016-01-01

    Full Text Available This study proposes the use of a split covariance intersection algorithm (Split-CI for decentralized multirobot cooperative localization. In the proposed method, each robot maintains a local cubature Kalman filter to estimate its own pose in a predefined coordinate frame. When a robot receives pose information from neighbouring robots, it employs a Split-CI based approach to fuse this received measurement with its local belief. The computational and communicative complexities of the proposed algorithm increase linearly with the number of robots in the multirobot systems (MRS. The proposed method does not require fully connected synchronous communication channels between robots; in fact, it is applicable for MRS with asynchronous and partially connected communication networks. The pose estimation error of the proposed method is bounded. As the proposed method is capable of handling independent and interdependent information of the estimations separately, it does not generate overconfidence state estimations. The performance of the proposed method is compared with several multirobot localization approaches. The simulation and experiment results demonstrate that the proposed algorithm outperforms the single-robot localization algorithms and achieves approximately the same estimation accuracy as the centralized cooperative localization approach, but with reduced computational and communicative cost.

  20. Local electric dipole moments: A generalized approach.

    Science.gov (United States)

    Groß, Lynn; Herrmann, Carmen

    2016-09-30

    We present an approach for calculating local electric dipole moments for fragments of molecular or supramolecular systems. This is important for understanding chemical gating and solvent effects in nanoelectronics, atomic force microscopy, and intensities in infrared spectroscopy. Owing to the nonzero partial charge of most fragments, "naively" defined local dipole moments are origin-dependent. Inspired by previous work based on Bader's atoms-in-molecules (AIM) partitioning, we derive a definition of fragment dipole moments which achieves origin-independence by relying on internal reference points. Instead of bond critical points (BCPs) as in existing approaches, we use as few reference points as possible, which are located between the fragment and the remainder(s) of the system and may be chosen based on chemical intuition. This allows our approach to be used with AIM implementations that circumvent the calculation of critical points for reasons of computational efficiency, for cases where no BCPs are found due to large interfragment distances, and with local partitioning schemes other than AIM which do not provide BCPs. It is applicable to both covalently and noncovalently bound systems. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. Direct comparison of enzyme histochemical and immunohistochemical methods to localize an enzyme

    NARCIS (Netherlands)

    van Noorden, Cornelis J. F.

    2002-01-01

    Immunohistochemical localization of enzymes is compared directly with localization of enzyme activity with (catalytic) enzyme histochemical methods. The two approaches demonstrate principally different aspects of an enzyme. The immunohistochemical method localizes the enzyme protein whether it is

  2. Local defect correction for boundary integral equation methods

    NARCIS (Netherlands)

    Kakuba, G.; Anthonissen, M.J.H.

    2013-01-01

    This paper presents a new approach to gridding for problems with localised regions of high activity. The technique of local defect correction has been studied for other methods as ¿nite difference methods and ¿nite volume methods. In this paper we develop the technique for the boundary element

  3. An Integrated Approach to Indoor and Outdoor Localization

    Science.gov (United States)

    2017-04-17

    TITLE AND SUBTITLE An Integrated Approach to Indoor and Outdoor Localization 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA9550-12-1-0299 5c.   PROGRAM ELEMENT...Distribution approved for public release. Figure 5: A flowchart of the method of computing an initial position estimate by comparing a single WiFi scan

  4. A Joint Audio-Visual Approach to Audio Localization

    DEFF Research Database (Denmark)

    Jensen, Jesper Rindom; Christensen, Mads Græsbøll

    2015-01-01

    Localization of audio sources is an important research problem, e.g., to facilitate noise reduction. In the recent years, the problem has been tackled using distributed microphone arrays (DMA). A common approach is to apply direction-of-arrival (DOA) estimation on each array (denoted as nodes), a...... time-of-flight cameras. Moreover, we propose an optimal method for weighting such DOA and range information for audio localization. Our experiments on both synthetic and real data show that there is a clear, potential advantage of using the joint audiovisual localization framework....

  5. X-ray spectrum local method

    International Nuclear Information System (INIS)

    Avdonin, S.A.

    1985-01-01

    General characteristic and bases of X-ray spectrum local method used for qualitative and quantitative analyses of the mineral chemical composition with volumetric locality of several cubic micrometers. The method is based on the excitation in a sample of characteristic and bremsstrahlung spectra by means of a narrow electron beam at 5-50 keV accelerating voltage. Application of the method when studying uranium minerals and ores is considered. The method allows to determine the uranium presence forms in the ores, morphological features of the minerals, mineral microstructure, UO 2 and UO 3 ratios for unhydrous uraninites and pitchblendes and also to determine mineralization age

  6. Analysis of Non Local Image Denoising Methods

    Science.gov (United States)

    Pardo, Álvaro

    Image denoising is probably one of the most studied problems in the image processing community. Recently a new paradigm on non local denoising was introduced. The Non Local Means method proposed by Buades, Morel and Coll attracted the attention of other researches who proposed improvements and modifications to their proposal. In this work we analyze those methods trying to understand their properties while connecting them to segmentation based on spectral graph properties. We also propose some improvements to automatically estimate the parameters used on these methods.

  7. Novel approach to assess local market power considering transmission constraints

    International Nuclear Information System (INIS)

    Li, Canbing; Xia, Qing; Kang, Chongqing; Jiang, Jianjian

    2008-01-01

    Market power (MP) assessment and mitigation affect the efficiency of the generation market. The traditional indices such as HHI and Lerner index can not express local market power, which caused by transmission constraints. Transmission constraints divide the market into some smaller parts. Some generators can abuse their MP in one part but not in the whole market. This paper describes a new approach to assess market power. The main contributions of the new method can be summarized as following. First, the concept of local market is developed, and the whole power system is divided into several local markets, as transmission congestions dividing the market. In the local markets, there are no transmission constraints so local market power does not exist. Then the local market power index (LMPI) is calculated according to market concentration, transmission constraints, and demand-supply ratio. Based on LMPI, the integrated local market power index which describes the whole picture of market can be obtained. It has been proved that the new approach can assess market power exactly, and identify the critical factor that results in market power and where generators are easy to exercise market power. The finding in this paper is helpful for market monitoring and mitigating market power. Moreover, the new index can be used to evaluate the power grid availability to generation competition and the power transmission expansion planning. (author)

  8. Local Search Approaches in Stable Matching Problems

    Directory of Open Access Journals (Sweden)

    Toby Walsh

    2013-10-01

    Full Text Available The stable marriage (SM problem has a wide variety of practical applications, ranging from matching resident doctors to hospitals, to matching students to schools or, more generally, to any two-sided market. In the classical formulation, n men and n women express their preferences (via a strict total order over the members of the other sex. Solving an SM problem means finding a stable marriage where stability is an envy-free notion: no man and woman who are not married to each other would both prefer each other to their partners or to being single. We consider both the classical stable marriage problem and one of its useful variations (denoted SMTI (Stable Marriage with Ties and Incomplete lists where the men and women express their preferences in the form of an incomplete preference list with ties over a subset of the members of the other sex. Matchings are permitted only with people who appear in these preference lists, and we try to find a stable matching that marries as many people as possible. Whilst the SM problem is polynomial to solve, the SMTI problem is NP-hard. We propose to tackle both problems via a local search approach, which exploits properties of the problems to reduce the size of the neighborhood and to make local moves efficiently. We empirically evaluate our algorithm for SM problems by measuring its runtime behavior and its ability to sample the lattice of all possible stable marriages. We evaluate our algorithm for SMTI problems in terms of both its runtime behavior and its ability to find a maximum cardinality stable marriage. Experimental results suggest that for SM problems, the number of steps of our algorithm grows only as O(n log(n, and that it samples very well the set of all stable marriages. It is thus a fair and efficient approach to generate stable marriages. Furthermore, our approach for SMTI problems is able to solve large problems, quickly returning stable matchings of large and often optimal size, despite the

  9. Multivariate localization methods for ensemble Kalman filtering

    KAUST Repository

    Roh, S.

    2015-12-03

    In ensemble Kalman filtering (EnKF), the small number of ensemble members that is feasible to use in a practical data assimilation application leads to sampling variability of the estimates of the background error covariances. The standard approach to reducing the effects of this sampling variability, which has also been found to be highly efficient in improving the performance of EnKF, is the localization of the estimates of the covariances. One family of localization techniques is based on taking the Schur (element-wise) product of the ensemble-based sample covariance matrix and a correlation matrix whose entries are obtained by the discretization of a distance-dependent correlation function. While the proper definition of the localization function for a single state variable has been extensively investigated, a rigorous definition of the localization function for multiple state variables that exist at the same locations has been seldom considered. This paper introduces two strategies for the construction of localization functions for multiple state variables. The proposed localization functions are tested by assimilating simulated observations experiments into the bivariate Lorenz 95 model with their help.

  10. Multivariate localization methods for ensemble Kalman filtering

    KAUST Repository

    Roh, S.

    2015-05-08

    In ensemble Kalman filtering (EnKF), the small number of ensemble members that is feasible to use in a practical data assimilation application leads to sampling variability of the estimates of the background error covariances. The standard approach to reducing the effects of this sampling variability, which has also been found to be highly efficient in improving the performance of EnKF, is the localization of the estimates of the covariances. One family of localization techniques is based on taking the Schur (entry-wise) product of the ensemble-based sample covariance matrix and a correlation matrix whose entries are obtained by the discretization of a distance-dependent correlation function. While the proper definition of the localization function for a single state variable has been extensively investigated, a rigorous definition of the localization function for multiple state variables has been seldom considered. This paper introduces two strategies for the construction of localization functions for multiple state variables. The proposed localization functions are tested by assimilating simulated observations experiments into the bivariate Lorenz 95 model with their help.

  11. Multivariate localization methods for ensemble Kalman filtering

    Science.gov (United States)

    Roh, S.; Jun, M.; Szunyogh, I.; Genton, M. G.

    2015-12-01

    In ensemble Kalman filtering (EnKF), the small number of ensemble members that is feasible to use in a practical data assimilation application leads to sampling variability of the estimates of the background error covariances. The standard approach to reducing the effects of this sampling variability, which has also been found to be highly efficient in improving the performance of EnKF, is the localization of the estimates of the covariances. One family of localization techniques is based on taking the Schur (element-wise) product of the ensemble-based sample covariance matrix and a correlation matrix whose entries are obtained by the discretization of a distance-dependent correlation function. While the proper definition of the localization function for a single state variable has been extensively investigated, a rigorous definition of the localization function for multiple state variables that exist at the same locations has been seldom considered. This paper introduces two strategies for the construction of localization functions for multiple state variables. The proposed localization functions are tested by assimilating simulated observations experiments into the bivariate Lorenz 95 model with their help.

  12. Multivariate localization methods for ensemble Kalman filtering

    KAUST Repository

    Roh, S.; Jun, M.; Szunyogh, I.; Genton, Marc G.

    2015-01-01

    In ensemble Kalman filtering (EnKF), the small number of ensemble members that is feasible to use in a practical data assimilation application leads to sampling variability of the estimates of the background error covariances. The standard approach to reducing the effects of this sampling variability, which has also been found to be highly efficient in improving the performance of EnKF, is the localization of the estimates of the covariances. One family of localization techniques is based on taking the Schur (entry-wise) product of the ensemble-based sample covariance matrix and a correlation matrix whose entries are obtained by the discretization of a distance-dependent correlation function. While the proper definition of the localization function for a single state variable has been extensively investigated, a rigorous definition of the localization function for multiple state variables has been seldom considered. This paper introduces two strategies for the construction of localization functions for multiple state variables. The proposed localization functions are tested by assimilating simulated observations experiments into the bivariate Lorenz 95 model with their help.

  13. Epileptogenic focus localization: a new approach

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, Vânia [Institute of Biophysics and Biomedical Engineering, Faculty of Sciences of the University of Lisbon, Lisboa (Portugal); Ribeiro, André Santos [Institute of Biophysics and Biomedical Engineering, Faculty of Sciences of the University of Lisbon, Lisboa (Portugal); Centre for Neuropsychopharmacology, Division of Brain Sciences, Department of Medicine, Imperial College London, London (United Kingdom); Capela, Carlos; Cerqueira, Luís [Department of Neuroradiology, Centro Hospitalar Lisboa Central, Lisbon (Portugal); Ferreira, Hugo Alexandre [Institute of Biophysics and Biomedical Engineering, Faculty of Sciences of the University of Lisbon, Lisboa (Portugal)

    2015-05-18

    Epilepsy is one of the most important chronic neurological disorders worldwide affecting more than 50 million people of all ages. Among these, almost 20% of epilepsy cases are uncontrollable and have an unknown source of this abnormal electrical activity. Present techniques for the detection of epileptogenic foci include electroencephalography (EEG), positron emission tomography, and multimodal EEG/functional magnetic resonance imaging (fMRI), all with limitations in terms of spatial and temporal resolutions. In order to overcome some of those limitations a novel approach using fMRI alone was developed based on the hypotheses that the epileptogenic focus shows Blood Oxygen Level Dependent (BOLD) temporal profiles distinct from the remaining brain parenchyma during interictal activity and that the epileptogenic focus BOLD signals show lower complexity than healthy parenchyma. In this novel approach, bi-dimensional temporal clustering analysis, a data-driven technique, was used to identify brain regions with similar temporal profiles. Then, the BOLD signals of these regions were assessed regarding complexity using detrended fluctuation analysis and also using a modified multiscale entropy algorithm in order to identify which of those regions corresponded to epileptogenic tissue. In order to demonstrate the applicability of the developed method three epileptic patients were analyzed comprising two types of epilepsy: unilateral and bilateral temporal lobe epilepsies. The results showed that this method is able to detect the brain regions associated with epileptogenic tissue. The results also showed that the epileptogenic focus influences the dynamics of related brain networks. This could be a key factor in the applicability of this method to other epilepsy cases. Finally, new perspectives are envisioned concerning the use of this method in the medical care of epilepsy. In particular, by improving this method using simultaneous structural, functional, and metabolic

  14. Epileptogenic focus localization: a new approach

    International Nuclear Information System (INIS)

    Tavares, Vânia; Ribeiro, André Santos; Capela, Carlos; Cerqueira, Luís; Ferreira, Hugo Alexandre

    2015-01-01

    Epilepsy is one of the most important chronic neurological disorders worldwide affecting more than 50 million people of all ages. Among these, almost 20% of epilepsy cases are uncontrollable and have an unknown source of this abnormal electrical activity. Present techniques for the detection of epileptogenic foci include electroencephalography (EEG), positron emission tomography, and multimodal EEG/functional magnetic resonance imaging (fMRI), all with limitations in terms of spatial and temporal resolutions. In order to overcome some of those limitations a novel approach using fMRI alone was developed based on the hypotheses that the epileptogenic focus shows Blood Oxygen Level Dependent (BOLD) temporal profiles distinct from the remaining brain parenchyma during interictal activity and that the epileptogenic focus BOLD signals show lower complexity than healthy parenchyma. In this novel approach, bi-dimensional temporal clustering analysis, a data-driven technique, was used to identify brain regions with similar temporal profiles. Then, the BOLD signals of these regions were assessed regarding complexity using detrended fluctuation analysis and also using a modified multiscale entropy algorithm in order to identify which of those regions corresponded to epileptogenic tissue. In order to demonstrate the applicability of the developed method three epileptic patients were analyzed comprising two types of epilepsy: unilateral and bilateral temporal lobe epilepsies. The results showed that this method is able to detect the brain regions associated with epileptogenic tissue. The results also showed that the epileptogenic focus influences the dynamics of related brain networks. This could be a key factor in the applicability of this method to other epilepsy cases. Finally, new perspectives are envisioned concerning the use of this method in the medical care of epilepsy. In particular, by improving this method using simultaneous structural, functional, and metabolic

  15. Multivariate localization methods for ensemble Kalman filtering

    OpenAIRE

    S. Roh; M. Jun; I. Szunyogh; M. G. Genton

    2015-01-01

    In ensemble Kalman filtering (EnKF), the small number of ensemble members that is feasible to use in a practical data assimilation application leads to sampling variability of the estimates of the background error covariances. The standard approach to reducing the effects of this sampling variability, which has also been found to be highly efficient in improving the performance of EnKF, is the localization of the estimates of the covariances. One family of ...

  16. Approaches to local climate action in Colorado

    Science.gov (United States)

    Huang, Y. D.

    2011-12-01

    Though climate change is a global problem, the impacts are felt on the local scale; it follows that the solutions must come at the local level. Fortunately, many cities and municipalities are implementing climate mitigation (or climate action) policies and programs. However, they face many procedural and institutional barriers to their efforts, such of lack of expertise or data, limited human and financial resources, and lack of community engagement (Krause 2011). To address the first obstacle, thirteen in-depth case studies were done of successful model practices ("best practices") of climate action programs carried out by various cities, counties, and organizations in Colorado, and one outside Colorado, and developed into "how-to guides" for other municipalities to use. Research was conducted by reading documents (e.g. annual reports, community guides, city websites), email correspondence with program managers and city officials, and via phone interviews. The information gathered was then compiled into a series of reports containing a narrative description of the initiative; an overview of the plan elements (target audience and goals); implementation strategies and any indicators of success to date (e.g. GHG emissions reductions, cost savings); and the adoption or approval process, as well as community engagement efforts and marketing or messaging strategies. The types of programs covered were energy action plans, energy efficiency programs, renewable energy programs, and transportation and land use programs. Between the thirteen case studies, there was a range of approaches to implementing local climate action programs, examined along two dimensions: focus on climate change (whether it was direct/explicit or indirect/implicit) and extent of government authority. This benchmarking exercise affirmed the conventional wisdom propounded by Pitt (2010), that peer pressure (that is, the presence of neighboring jurisdictions with climate initiatives), the level of

  17. Adaptive ACMS: A robust localized Approximated Component Mode Synthesis Method

    OpenAIRE

    Madureira, Alexandre L.; Sarkis, Marcus

    2017-01-01

    We consider finite element methods of multiscale type to approximate solutions for two-dimensional symmetric elliptic partial differential equations with heterogeneous $L^\\infty$ coefficients. The methods are of Galerkin type and follows the Variational Multiscale and Localized Orthogonal Decomposition--LOD approaches in the sense that it decouples spaces into multiscale and fine subspaces. In a first method, the multiscale basis functions are obtained by mapping coarse basis functions, based...

  18. Comparison of Localization Methods for a Robot Soccer Team

    Directory of Open Access Journals (Sweden)

    H. Levent Akın

    2008-11-01

    Full Text Available In this work, several localization algorithms that are designed and implemented for Cerberus'05 Robot Soccer Team are analyzed and compared. These algorithms are used for global localization of autonomous mobile agents in the robotic soccer domain, to overcome the uncertainty in the sensors, environment and the motion model. The algorithms are Reverse Monte Carlo Localization (R-MCL, Simple Localization (S-Loc and Sensor Resetting Localization (SRL. R-MCL is a hybrid method based on both Markov Localization (ML and Monte Carlo Localization (MCL where the ML module finds the region where the robot should be and MCL predicts the geometrical location with high precision by selecting samples in this region. S-Loc is another localization method where just one sample per percept is drawn, for global localization. Within this method another novel method My Environment (ME is designed to hold the history and overcome the lack of information due to the drastically decrease in the number of samples in S-Loc. ME together with S-Loc is used in the Technical Challenges in Robocup 2005 and play an important role in ranking the First Place in the Challenges. In this work, these methods together with SRL, which is a widely used successful localization algorithm, are tested with both offline and real-time tests. First they are tested on a challenging data set that is used by many researches and compared in terms of error rate against different levels of noise, and sparsity. Besides time required recovering from kidnapping and speed of the methods are tested and compared. Then their performances are tested with real-time tests with scenarios like the ones in the Technical Challenges in ROBOCUP. The main aim is to find the best method which is very robust and fast and requires less computational power and memory compared to similar approaches and is accurate enough for high level decision making which is vital for robot soccer.

  19. Comparison of Localization Methods for a Robot Soccer Team

    Directory of Open Access Journals (Sweden)

    Hatice Kose

    2006-12-01

    Full Text Available In this work, several localization algorithms that are designed and implemented for Cerberus'05 Robot Soccer Team are analyzed and compared. These algorithms are used for global localization of autonomous mobile agents in the robotic soccer domain, to overcome the uncertainty in the sensors, environment and the motion model. The algorithms are Reverse Monte Carlo Localization (R-MCL, Simple Localization (S-Loc and Sensor Resetting Localization (SRL. R-MCL is a hybrid method based on both Markov Localization (ML and Monte Carlo Localization (MCL where the ML module finds the region where the robot should be and MCL predicts the geometrical location with high precision by selecting samples in this region. S-Loc is another localization method where just one sample per percept is drawn, for global localization. Within this method another novel method My Environment (ME is designed to hold the history and overcome the lack of information due to the drastically decrease in the number of samples in S-Loc. ME together with S-Loc is used in the Technical Challenges in Robocup 2005 and play an important role in ranking the First Place in the Challenges. In this work, these methods together with SRL, which is a widely used successful localization algorithm, are tested with both offline and real-time tests. First they are tested on a challenging data set that is used by many researches and compared in terms of error rate against different levels of noise, and sparsity. Besides time required recovering from kidnapping and speed of the methods are tested and compared. Then their performances are tested with real-time tests with scenarios like the ones in the Technical Challenges in ROBOCUP. The main aim is to find the best method which is very robust and fast and requires less computational power and memory compared to similar approaches and is accurate enough for high level decision making which is vital for robot soccer.

  20. Global approaches and local strategies for phase unwrapping

    International Nuclear Information System (INIS)

    Guerriero, L.; Refice, A.; Stramaglia, S.; Chiaradia, M. T.; Satalino, G.; Veneziani, N.; Blonda, P.; Pasquariello, G.

    2001-01-01

    Phase unwrapping, i.e. the retrieval of absolute phases from wrapped, noisy measures, is a tough problem because of the presence of rotational inconsistencies (residues), randomly generated by noise and undersampling on the principal phase gradient field. These inconsistencies prevent the recovery of the absolute phase field by direct integration of the wrapped gradients. In this paper it is examined the relative merit of known global approaches and then it is presented evidence that the approach based on stochastic annealing can recover the true phase field also in noisy areas with severe undersampling, where other methods fail. Then, some experiments with local approaches are presented. A fast neural filter has been trained to eliminate close residue couples by joining them in a way which takes into account the local phase information. Performances are about 60-70% of the residues. Finally, other experiments have been aimed at designing an automated method for the determination of weight matrices to use in conjunction with local phase unwrapping algorithms. The method, tested with the minimum cost flow algorithm, gives good performances over both simulated and real data

  1. New Approaches for Solving Fokker Planck Equation on Cantor Sets within Local Fractional Operators

    Directory of Open Access Journals (Sweden)

    Hassan Kamil Jassim

    2015-01-01

    Full Text Available We discuss new approaches to handling Fokker Planck equation on Cantor sets within local fractional operators by using the local fractional Laplace decomposition and Laplace variational iteration methods based on the local fractional calculus. The new approaches maintain the efficiency and accuracy of the analytical methods for solving local fractional differential equations. Illustrative examples are given to show the accuracy and reliable results.

  2. Localized-overlap approach to calculations of intermolecular interactions

    Science.gov (United States)

    Rob, Fazle

    Symmetry-adapted perturbation theory (SAPT) based on the density functional theory (DFT) description of the monomers [SAPT(DFT)] is one of the most robust tools for computing intermolecular interaction energies. Currently, one can use the SAPT(DFT) method to calculate interaction energies of dimers consisting of about a hundred atoms. To remove the methodological and technical limits and extend the size of the systems that can be calculated with the method, a novel approach has been proposed that redefines the electron densities and polarizabilities in a localized way. In the new method, accurate but computationally expensive quantum-chemical calculations are only applied for the regions where it is necessary and for other regions, where overlap effects of the wave functions are negligible, inexpensive asymptotic techniques are used. Unlike other hybrid methods, this new approach is mathematically rigorous. The main benefit of this method is that with the increasing size of the system the calculation scales linearly and, therefore, this approach will be denoted as local-overlap SAPT(DFT) or LSAPT(DFT). As a byproduct of developing LSAPT(DFT), some important problems concerning distributed molecular response, in particular, the unphysical charge-flow terms were eliminated. Additionally, to illustrate the capabilities of SAPT(DFT), a potential energy function has been developed for an energetic molecular crystal of 1,1-diamino-2,2-dinitroethylene (FOX-7), where an excellent agreement with the experimental data has been found.

  3. Local Relation Map: A Novel Illumination Invariant Face Recognition Approach

    Directory of Open Access Journals (Sweden)

    Lian Zhichao

    2012-10-01

    Full Text Available In this paper, a novel illumination invariant face recognition approach is proposed. Different from most existing methods, an additive term as noise is considered in the face model under varying illuminations in addition to a multiplicative illumination term. High frequency coefficients of Discrete Cosine Transform (DCT are discarded to eliminate the effect caused by noise. Based on the local characteristics of the human face, a simple but effective illumination invariant feature local relation map is proposed. Experimental results on the Yale B, Extended Yale B and CMU PIE demonstrate the outperformance and lower computational burden of the proposed method compared to other existing methods. The results also demonstrate the validity of the proposed face model and the assumption on noise.

  4. The Dutch Approach to Local Climate Action

    International Nuclear Information System (INIS)

    Schellekens, R.

    2008-01-01

    In the Netherlands we are working with municipalities on the subjects of RES and RUE for over 15 years now. Over the last 4 years we worked with 250 out of 430 municipalities on setting up and executing their local climate policies. For this there was a national climate covenant between the national government, the association of municipalities and the association of provinces. The municipalities and provinces were supported through a subsidy scheme and the help of SenterNovem. Products like the climate menu, the climate scan and an organisational assessment were developed to aid the municipalities in their process. Through involvement of different stake holders within the municipality or a region concerning the climate policy and the execution thereof, production of RES is stimulated and goals on energy saving are more likely to be reached. Through the involvement of stake holders and by making climate change an integral part of the municipal organisation an irreversible process is started. Thus economic competitiveness and innovations are stimulated. The municipality and the region will gain economic strength through this. Results in the Netherlands on a municipal level are inspiring. More and more municipalities are developing long-term strategies at the moment. Goals like energy neutrality, climate neutrality and CO 2 neutrality in a set year are usually the basis of these strategies. Through these strategies Dutch municipalities become increasingly less dependent on energy sources outside their boarders. On a European level the Dutch approach ties in with the Covenant of Mayors which is launched by the EU.(author)

  5. Enhanced Methods for Local Ancestry Assignment in Sequenced Admixed Individuals

    Science.gov (United States)

    Brown, Robert; Pasaniuc, Bogdan

    2014-01-01

    Inferring the ancestry at each locus in the genome of recently admixed individuals (e.g., Latino Americans) plays a major role in medical and population genetic inferences, ranging from finding disease-risk loci, to inferring recombination rates, to mapping missing contigs in the human genome. Although many methods for local ancestry inference have been proposed, most are designed for use with genotyping arrays and fail to make use of the full spectrum of data available from sequencing. In addition, current haplotype-based approaches are very computationally demanding, requiring large computational time for moderately large sample sizes. Here we present new methods for local ancestry inference that leverage continent-specific variants (CSVs) to attain increased performance over existing approaches in sequenced admixed genomes. A key feature of our approach is that it incorporates the admixed genomes themselves jointly with public datasets, such as 1000 Genomes, to improve the accuracy of CSV calling. We use simulations to show that our approach attains accuracy similar to widely used computationally intensive haplotype-based approaches with large decreases in runtime. Most importantly, we show that our method recovers comparable local ancestries, as the 1000 Genomes consensus local ancestry calls in the real admixed individuals from the 1000 Genomes Project. We extend our approach to account for low-coverage sequencing and show that accurate local ancestry inference can be attained at low sequencing coverage. Finally, we generalize CSVs to sub-continental population-specific variants (sCSVs) and show that in some cases it is possible to determine the sub-continental ancestry for short chromosomal segments on the basis of sCSVs. PMID:24743331

  6. Optic disk localization by a robust fusion method

    Science.gov (United States)

    Zhang, Jielin; Yin, Fengshou; Wong, Damon W. K.; Liu, Jiang; Baskaran, Mani; Cheng, Ching-Yu; Wong, Tien Yin

    2013-02-01

    The optic disk localization plays an important role in developing computer-aided diagnosis (CAD) systems for ocular diseases such as glaucoma, diabetic retinopathy and age-related macula degeneration. In this paper, we propose an intelligent fusion of methods for the localization of the optic disk in retinal fundus images. Three different approaches are developed to detect the location of the optic disk separately. The first method is the maximum vessel crossing method, which finds the region with the most number of blood vessel crossing points. The second one is the multichannel thresholding method, targeting the area with the highest intensity. The final method searches the vertical and horizontal region-of-interest separately on the basis of blood vessel structure and neighborhood entropy profile. Finally, these three methods are combined using an intelligent fusion method to improve the overall accuracy. The proposed algorithm was tested on the STARE database and the ORIGAlight database, each consisting of images with various pathologies. The preliminary result on the STARE database can achieve 81.5%, while a higher result of 99% can be obtained for the ORIGAlight database. The proposed method outperforms each individual approach and state-of-the-art method which utilizes an intensity-based approach. The result demonstrates a high potential for this method to be used in retinal CAD systems.

  7. Modelling of ductile and cleavage fracture by local approach

    International Nuclear Information System (INIS)

    Samal, M.K.; Dutta, B.K.; Kushwaha, H.S.

    2000-08-01

    This report describes the modelling of ductile and cleavage fracture processes by local approach. It is now well known that the conventional fracture mechanics method based on single parameter criteria is not adequate to model the fracture processes. It is because of the existence of effect of size and geometry of flaw, loading type and rate on the fracture resistance behaviour of any structure. Hence, it is questionable to use same fracture resistance curves as determined from standard tests in the analysis of real life components because of existence of all the above effects. So, there is need to have a method in which the parameters used for the analysis will be true material properties, i.e. independent of geometry and size. One of the solutions to the above problem is the use of local approaches. These approaches have been extensively studied and applied to different materials (including SA33 Gr.6) in this report. Each method has been studied and reported in a separate section. This report has been divided into five sections. Section-I gives a brief review of the fundamentals of fracture process. Section-II deals with modelling of ductile fracture by locally uncoupled type of models. In this section, the critical cavity growth parameters of the different models have been determined for the primary heat transport (PHT) piping material of Indian pressurised heavy water reactor (PHWR). A comparative study has been done among different models. The dependency of the critical parameters on stress triaxiality factor has also been studied. It is observed that Rice and Tracey's model is the most suitable one. But, its parameters are not fully independent of triaxiality factor. For this purpose, a modification to Rice and Tracery's model is suggested in Section-III. Section-IV deals with modelling of ductile fracture process by locally coupled type of models. Section-V deals with the modelling of cleavage fracture process by Beremins model, which is based on Weibulls

  8. Global/local methods for probabilistic structural analysis

    Science.gov (United States)

    Millwater, H. R.; Wu, Y.-T.

    1993-04-01

    A probabilistic global/local method is proposed to reduce the computational requirements of probabilistic structural analysis. A coarser global model is used for most of the computations with a local more refined model used only at key probabilistic conditions. The global model is used to establish the cumulative distribution function (cdf) and the Most Probable Point (MPP). The local model then uses the predicted MPP to adjust the cdf value. The global/local method is used within the advanced mean value probabilistic algorithm. The local model can be more refined with respect to the g1obal model in terms of finer mesh, smaller time step, tighter tolerances, etc. and can be used with linear or nonlinear models. The basis for this approach is described in terms of the correlation between the global and local models which can be estimated from the global and local MPPs. A numerical example is presented using the NESSUS probabilistic structural analysis program with the finite element method used for the structural modeling. The results clearly indicate a significant computer savings with minimal loss in accuracy.

  9. The Microsociological Approach on Local Development Studies

    Directory of Open Access Journals (Sweden)

    Lic. Domingos António-Lópes

    2015-10-01

    Full Text Available In the past two decades, societies, economies and cultures of the countries developed and developing have lived deep structural changes of marked breadth and impact processes in everyday lives.  Today we are witnessing a new era of technological and organizational restructuring that affects the ways to produce and manage local development. Sociology as a social science has begun to rethink development from the voices of a variety of actors, to strike with them rhythms and intensities of the social and cultural dynamics. This article is a sociological study on local development from the perspective of culture, placing the concepts of social space and socialization practices. An analysis of documentary sources which favoured the systematization of the concepts of development and local development.Keywords:  development, local development, socialization, cultural practices, social space, social capital.

  10. Evaluation Methodology between Globalization and Localization Features Approaches for Skin Cancer Lesions Classification

    Science.gov (United States)

    Ahmed, H. M.; Al-azawi, R. J.; Abdulhameed, A. A.

    2018-05-01

    Huge efforts have been put in the developing of diagnostic methods to skin cancer disease. In this paper, two different approaches have been addressed for detection the skin cancer in dermoscopy images. The first approach uses a global method that uses global features for classifying skin lesions, whereas the second approach uses a local method that uses local features for classifying skin lesions. The aim of this paper is selecting the best approach for skin lesion classification. The dataset has been used in this paper consist of 200 dermoscopy images from Pedro Hispano Hospital (PH2). The achieved results are; sensitivity about 96%, specificity about 100%, precision about 100%, and accuracy about 97% for globalization approach while, sensitivity about 100%, specificity about 100%, precision about 100%, and accuracy about 100% for Localization Approach, these results showed that the localization approach achieved acceptable accuracy and better than globalization approach for skin cancer lesions classification.

  11. Perception approaches and practices of local farming and development: an anthropological approach

    International Nuclear Information System (INIS)

    Hadi, S.A.; Chaudhry, A.G.

    2015-01-01

    The study focused on recognizing the local approaches of farming in designing and implementation of development projects. These approaches are representative of a particular ecological, social, economical, and political system, shaped by the constraints and opportunities associated to the area. Effective and successful development projects must include the local perceptions, their approaches and practices, as the locals are the ones most representative of their issues and have the most workable solution to them. The traditional agriculture has completely been clutched into the nexus of modern farming methods, due to which they are being abandoned by the farmers. Modern farming which is representative of development has increased the competition, transitioning, breaking the community into people experimenting on modern technology and those who are still finding means to adapt their traditional agriculture to the fast changing needs of the societies. The research was carried out in the villages of Ghora Gali and Aruka through qualitative and quantitative methods. Sustainable development in Pakistan thus needs to be reinvented in the local perspective considering approaches and practices and, eradicating the alien chains of development completely. (author)

  12. MFAM: Multiple Frequency Adaptive Model-Based Indoor Localization Method.

    Science.gov (United States)

    Tuta, Jure; Juric, Matjaz B

    2018-03-24

    This paper presents MFAM (Multiple Frequency Adaptive Model-based localization method), a novel model-based indoor localization method that is capable of using multiple wireless signal frequencies simultaneously. It utilizes indoor architectural model and physical properties of wireless signal propagation through objects and space. The motivation for developing multiple frequency localization method lies in the future Wi-Fi standards (e.g., 802.11ah) and the growing number of various wireless signals present in the buildings (e.g., Wi-Fi, Bluetooth, ZigBee, etc.). Current indoor localization methods mostly rely on a single wireless signal type and often require many devices to achieve the necessary accuracy. MFAM utilizes multiple wireless signal types and improves the localization accuracy over the usage of a single frequency. It continuously monitors signal propagation through space and adapts the model according to the changes indoors. Using multiple signal sources lowers the required number of access points for a specific signal type while utilizing signals, already present in the indoors. Due to the unavailability of the 802.11ah hardware, we have evaluated proposed method with similar signals; we have used 2.4 GHz Wi-Fi and 868 MHz HomeMatic home automation signals. We have performed the evaluation in a modern two-bedroom apartment and measured mean localization error 2.0 to 2.3 m and median error of 2.0 to 2.2 m. Based on our evaluation results, using two different signals improves the localization accuracy by 18% in comparison to 2.4 GHz Wi-Fi-only approach. Additional signals would improve the accuracy even further. We have shown that MFAM provides better accuracy than competing methods, while having several advantages for real-world usage.

  13. MFAM: Multiple Frequency Adaptive Model-Based Indoor Localization Method

    Directory of Open Access Journals (Sweden)

    Jure Tuta

    2018-03-01

    Full Text Available This paper presents MFAM (Multiple Frequency Adaptive Model-based localization method, a novel model-based indoor localization method that is capable of using multiple wireless signal frequencies simultaneously. It utilizes indoor architectural model and physical properties of wireless signal propagation through objects and space. The motivation for developing multiple frequency localization method lies in the future Wi-Fi standards (e.g., 802.11ah and the growing number of various wireless signals present in the buildings (e.g., Wi-Fi, Bluetooth, ZigBee, etc.. Current indoor localization methods mostly rely on a single wireless signal type and often require many devices to achieve the necessary accuracy. MFAM utilizes multiple wireless signal types and improves the localization accuracy over the usage of a single frequency. It continuously monitors signal propagation through space and adapts the model according to the changes indoors. Using multiple signal sources lowers the required number of access points for a specific signal type while utilizing signals, already present in the indoors. Due to the unavailability of the 802.11ah hardware, we have evaluated proposed method with similar signals; we have used 2.4 GHz Wi-Fi and 868 MHz HomeMatic home automation signals. We have performed the evaluation in a modern two-bedroom apartment and measured mean localization error 2.0 to 2.3 m and median error of 2.0 to 2.2 m. Based on our evaluation results, using two different signals improves the localization accuracy by 18% in comparison to 2.4 GHz Wi-Fi-only approach. Additional signals would improve the accuracy even further. We have shown that MFAM provides better accuracy than competing methods, while having several advantages for real-world usage.

  14. A new approach for detecting local features

    DEFF Research Database (Denmark)

    Nguyen, Phuong Giang; Andersen, Hans Jørgen

    2010-01-01

    Local features up to now are often mentioned in the meaning of interest points. A patch around each point is formed to compute descriptors or feature vectors. Therefore, in order to satisfy different invariant imaging conditions such as scales and viewpoints, an input image is often represented i...

  15. Remote leak localization approach for fusion machines

    International Nuclear Information System (INIS)

    Durocher, Au.; Bruno, V.; Chantant, M.; Gargiulo, L.; Gherman, T.; Hatchressian, J.-C.; Houry, M.; Le, R.; Mouyon, D.

    2013-01-01

    Highlights: ► Description of leaks issue. ► Selection of leak localization concepts. ► Qualification of leak localization concepts. -- Abstract: Fusion machine operation requires high-vacuum conditions and does not tolerate water or gas leak in the vacuum vessels, even if they are micrometric. Tore Supra, as a fully actively cooled tokamak, has got a large leak management experience; 34 water leaks occurred since the beginning of its operation in 1988. To handle this issue, after preliminary machine protection phases, the current process for leak localization is based on water or helium pressurization network by network. It generally allows the identification of a set of components where the leakage element is located. However, the unique background of CEA-IRFM laboratory points needs of accuracy and promptness out in the leak localization process. Moreover, in-vessel interventions have to be performed trying to minimize time and risks for the persons. They are linked to access conditions, radioactivity, tracer gas high pressure and vessel conditioning. Remote operation will be one of the ways to improve these points on future fusion machines. In this case, leak sensors would have to be light weight devices in order to be integrated on a carrier or to be located outside with a sniffing process set up. A leak localization program is on-going at CEA-IRFM Laboratory with the first goal of identifying and characterizing relevant concepts to localize helium or water leaks on ITER. In the same time, CEA has developed robotic carrier for effective in-vessel intervention in a hostile environment. Three major tests campaigns with the goal to identify leak sensors have been achieved on several CEA test-beds since 2010. Very promising results have been obtained: relevant scenario of leak localization performed, concepts tested in a high volume test-bed called TITAN, and, in several conditions of pressure and temperature (ultrahigh vacuum to atmospheric pressure and 20

  16. Remote leak localization approach for fusion machines

    Energy Technology Data Exchange (ETDEWEB)

    Durocher, Au., E-mail: aurelien.durocher@cea.fr [CEA-IRFM, F-13108 Saint Paul-Lez-Durance (France); Bruno, V.; Chantant, M.; Gargiulo, L. [CEA-IRFM, F-13108 Saint Paul-Lez-Durance (France); Gherman, T. [Floralis UJF Filiale, F-38610 Gières (France); Hatchressian, J.-C.; Houry, M.; Le, R.; Mouyon, D. [CEA-IRFM, F-13108 Saint Paul-Lez-Durance (France)

    2013-10-15

    Highlights: ► Description of leaks issue. ► Selection of leak localization concepts. ► Qualification of leak localization concepts. -- Abstract: Fusion machine operation requires high-vacuum conditions and does not tolerate water or gas leak in the vacuum vessels, even if they are micrometric. Tore Supra, as a fully actively cooled tokamak, has got a large leak management experience; 34 water leaks occurred since the beginning of its operation in 1988. To handle this issue, after preliminary machine protection phases, the current process for leak localization is based on water or helium pressurization network by network. It generally allows the identification of a set of components where the leakage element is located. However, the unique background of CEA-IRFM laboratory points needs of accuracy and promptness out in the leak localization process. Moreover, in-vessel interventions have to be performed trying to minimize time and risks for the persons. They are linked to access conditions, radioactivity, tracer gas high pressure and vessel conditioning. Remote operation will be one of the ways to improve these points on future fusion machines. In this case, leak sensors would have to be light weight devices in order to be integrated on a carrier or to be located outside with a sniffing process set up. A leak localization program is on-going at CEA-IRFM Laboratory with the first goal of identifying and characterizing relevant concepts to localize helium or water leaks on ITER. In the same time, CEA has developed robotic carrier for effective in-vessel intervention in a hostile environment. Three major tests campaigns with the goal to identify leak sensors have been achieved on several CEA test-beds since 2010. Very promising results have been obtained: relevant scenario of leak localization performed, concepts tested in a high volume test-bed called TITAN, and, in several conditions of pressure and temperature (ultrahigh vacuum to atmospheric pressure and 20

  17. Giant monopole transition densities within the local scale ATDHF approach

    International Nuclear Information System (INIS)

    Dimitrova, S.S.; Petkov, I.Zh.; Stoitsov, M.V.

    1986-01-01

    Transition densities for 12 C, 16 O, 28 Si, 32 S, 40 Ca, 48 Ca, 56 Ni, 90 Zr, 208 Pb even-even nuclei corresponding to nuclear glant monopole resonances obtained within a local-scale adiabatic time-dependent Hartree-Fook approach in terms of effective Skyrme-type forces SkM and S3. The approach, the particular form and all necessary coefficients of these transition densities are reported. They are of a simple analytical form and may be directly used for example in analyses of particle inelastic scattering on nuclei by distorted wave method and a such a way allowing a test of the theoretical interpretation of giant monopole resonances

  18. Local Fractional Laplace Variational Iteration Method for Solving Linear Partial Differential Equations with Local Fractional Derivative

    Directory of Open Access Journals (Sweden)

    Ai-Min Yang

    2014-01-01

    Full Text Available The local fractional Laplace variational iteration method was applied to solve the linear local fractional partial differential equations. The local fractional Laplace variational iteration method is coupled by the local fractional variational iteration method and Laplace transform. The nondifferentiable approximate solutions are obtained and their graphs are also shown.

  19. Synthesis of industrial applications of local approach to fracture models

    International Nuclear Information System (INIS)

    Eripret, C.

    1993-03-01

    This report gathers different applications of local approach to fracture models to various industrial configurations, such as nuclear pressure vessel steel, cast duplex stainless steels, or primary circuit welds such as bimetallic welds. As soon as models are developed on the basis of microstructural observations, damage mechanisms analyses, and fracture process, the local approach to fracture proves to solve problems where classical fracture mechanics concepts fail. Therefore, local approach appears to be a powerful tool, which completes the standard fracture criteria used in nuclear industry by exhibiting where and why those classical concepts become unvalid. (author). 1 tab., 18 figs., 25 refs

  20. Solving Local Violence by Cosmopolitan Democracy Approach

    Directory of Open Access Journals (Sweden)

    Muhammad Luthfil Hakim

    2016-05-01

    Full Text Available The implementation of democracy intensified since the fall of the new order era has some failures. One of the factors is violence phenomena still continue in the region. This study aims to discuss the violence in the region by presenting cosmopolitan democracy as a new design of more humane democracy. In addition, this research method uses library research, because library research can understand the problem in-depth to find the pattern and recommendation from the violence problems which happens in Indonesia. This study uses Hannah Arendt observations on the phenomenon of violence. In addition, the concept of cosmopolitan democracy is referred from Daniele Archibugi, David Held, and Ulrich Beck is presented as a draft of new democracy direction which is more inclusive and humane. The result of this study discloses that the occurrence of incidence is triggered by failed implementation of the democratic system in Indonesia.

  1. Local Fractional Adomian Decomposition and Function Decomposition Methods for Laplace Equation within Local Fractional Operators

    Directory of Open Access Journals (Sweden)

    Sheng-Ping Yan

    2014-01-01

    Full Text Available We perform a comparison between the local fractional Adomian decomposition and local fractional function decomposition methods applied to the Laplace equation. The operators are taken in the local sense. The results illustrate the significant features of the two methods which are both very effective and straightforward for solving the differential equations with local fractional derivative.

  2. Multigraph approach to quantum non-locality

    International Nuclear Information System (INIS)

    Rabelo, Rafael; Duarte, Cristhiano; Cunha, Marcelo Terra; López-Tarrida, Antonio J; Cabello, Adán

    2014-01-01

    Non-contextuality (NC) and Bell inequalities can be expressed as bounds Ω for positive linear combinations S of probabilities of events, S⩽Ω. Exclusive events in S can be represented as adjacent vertices of a graph called the exclusivity graph of S. In the case that events correspond to the outcomes of quantum projective measurements, quantum probabilities are intimately related to the Grötschel–Lovász–Schrijver theta body of the exclusivity graph. Then, one can easily compute an upper bound to the maximum quantum violation of any NC or Bell inequality by optimizing S over the theta body and calculating the Lovász number of the corresponding exclusivity graph. In some cases, this upper bound is tight and gives the exact maximum quantum violation. However, in general, this is not the case. The reason is that the exclusivity graph does not distinguish among the different ways exclusivity can occur in Bell-inequality (and similar) scenarios. An interesting question is whether there is a graph-theoretical concept which accounts for this problem. Here we show that, for any given N-partite Bell inequality, an edge-coloured multigraph composed of N single-colour graphs can be used to encode the relationships of exclusivity between each party's parts of the events. Then, the maximum quantum violation of the Bell inequality is exactly given by a refinement of the Lovász number that applies to these edge-coloured multigraphs. We show how to calculate upper bounds for this number using a hierarchy of semi-definite programs and calculate upper bounds for I 3 , I 3322 and the three bipartite Bell inequalities whose exclusivity graph is a pentagon. The multigraph-theoretical approach introduced here may remove some obstacles in the program of explaining quantum correlations from first principles. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘50 years of Bell’s theorem’. (paper)

  3. A novel Monte Carlo approach to hybrid local volatility models

    NARCIS (Netherlands)

    A.W. van der Stoep (Anton); L.A. Grzelak (Lech Aleksander); C.W. Oosterlee (Cornelis)

    2017-01-01

    textabstractWe present in a Monte Carlo simulation framework, a novel approach for the evaluation of hybrid local volatility [Risk, 1994, 7, 18–20], [Int. J. Theor. Appl. Finance, 1998, 1, 61–110] models. In particular, we consider the stochastic local volatility model—see e.g. Lipton et al. [Quant.

  4. Improving mobile robot localization: grid-based approach

    Science.gov (United States)

    Yan, Junchi

    2012-02-01

    Autonomous mobile robots have been widely studied not only as advanced facilities for industrial and daily life automation, but also as a testbed in robotics competitions for extending the frontier of current artificial intelligence. In many of such contests, the robot is supposed to navigate on the ground with a grid layout. Based on this observation, we present a localization error correction method by exploring the geometric feature of the tile patterns. On top of the classical inertia-based positioning, our approach employs three fiber-optic sensors that are assembled under the bottom of the robot, presenting an equilateral triangle layout. The sensor apparatus, together with the proposed supporting algorithm, are designed to detect a line's direction (vertical or horizontal) by monitoring the grid crossing events. As a result, the line coordinate information can be fused to rectify the cumulative localization deviation from inertia positioning. The proposed method is analyzed theoretically in terms of its error bound and also has been implemented and tested on a customary developed two-wheel autonomous mobile robot.

  5. Many-body-localization: strong disorder perturbative approach for the local integrals of motion

    Science.gov (United States)

    Monthus, Cécile

    2018-05-01

    For random quantum spin models, the strong disorder perturbative expansion of the local integrals of motion around the real-spin operators is revisited. The emphasis is on the links with other properties of the many-body-localized phase, in particular the memory in the dynamics of the local magnetizations and the statistics of matrix elements of local operators in the eigenstate basis. Finally, this approach is applied to analyze the many-body-localization transition in a toy model studied previously from the point of view of the entanglement entropy.

  6. Multivariate localization methods for ensemble Kalman filtering

    KAUST Repository

    Roh, S.; Jun, M.; Szunyogh, I.; Genton, Marc G.

    2015-01-01

    the Schur (element-wise) product of the ensemble-based sample covariance matrix and a correlation matrix whose entries are obtained by the discretization of a distance-dependent correlation function. While the proper definition of the localization function

  7. Formulation analysis and computation of an optimization-based local-to-nonlocal coupling method.

    Energy Technology Data Exchange (ETDEWEB)

    D' Elia, Marta [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Computing Research; Bochev, Pavel Blagoveston [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Computing Research

    2017-01-01

    In this paper, we present an optimization-based coupling method for local and nonlocal continuum models. Our approach couches the coupling of the models into a control problem where the states are the solutions of the nonlocal and local equations, the objective is to minimize their mismatch on the overlap of the local and nonlocal problem domains, and the virtual controls are the nonlocal volume constraint and the local boundary condition. We present the method in the context of Local-to-Nonlocal di usion coupling. Numerical examples illustrate the theoretical properties of the approach.

  8. Community-led local development approach principles implementation when forming a regional local development projects support system in Ukraine

    Directory of Open Access Journals (Sweden)

    Y. G. Udod

    2017-03-01

    Full Text Available The article contains a brief description of the Community-led local development approach (local development under the leadership of the community, CLLD and the main purpose of its use in the European Union. The study indicated periods of the major initiatives to support local development in EU. Moreover the article posted CLLD approach principles’ evolution and the basic principles of the LEADER method and its application in CLLD, which can be applied in Ukraine. Subject to the provisions of the European Economic and Social Committee (EESC for further CLLD-approach distribution the five trends were identified that must be considered when forming a Regional local development projects support system in Ukraine: Multi-fund financing; Unification; Networking and collaboration; Extending the approach; Simplifying the process. The characteristic of the present phase of CLLD-approach, in particular, of the European Network for Rural Development (ENRD, which attaches great importance to the dissemination of the most effective CLLD practices and establish partnerships between communities and territories where the approach is implemented. The study found out the relationship between Community-led local development and Community-driven development (CDD supported by the World Bank.

  9. Ex-post evaluation of local energy efficiency and demand-side management operations - State of the art, bottom-up methods, applied examples and approach for the development of an evaluation practical culture

    International Nuclear Information System (INIS)

    Broc, J.S.

    2006-12-01

    Energy end-use Efficiency (EE) is a priority for energy policies to face resources exhaustion and to reduce pollutant emissions. At the same time, in France, local level is increasingly involved into the implementation of EE activities, whose frame is changing (energy market liberalization, new policy instruments). Needs for ex-post evaluation of the local EE activities are thus increasing, for regulation requirements and to support a necessary change of scale. Our thesis focuses on the original issue of the ex-post evaluation of local EE operations in France. The state of the art, through the analysis of the American and European experiences and of the reference guidebooks, gives a substantial methodological material and emphasises the key evaluation issues. Concurrently, local EE operations in France are characterized by an analysis of their environment and a work on their segmentation criteria. The combination of these criteria with the key evaluation issues provides an analysis framework used as the basis for the composition of evaluation methods. This also highlights the specific evaluation needs for local operations. A methodology is then developed to complete and adapt the existing material to design evaluation methods for local operations, so that stakeholders can easily appropriate. Evaluation results thus feed a know-how building process with experience feedback. These methods are to meet two main goals: to determine the operation results, and to detect the success/failure factors. The methodology was validated on concrete cases, where these objectives were reached. (author)

  10. Local Approximation and Hierarchical Methods for Stochastic Optimization

    Science.gov (United States)

    Cheng, Bolong

    In this thesis, we present local and hierarchical approximation methods for two classes of stochastic optimization problems: optimal learning and Markov decision processes. For the optimal learning problem class, we introduce a locally linear model with radial basis function for estimating the posterior mean of the unknown objective function. The method uses a compact representation of the function which avoids storing the entire history, as is typically required by nonparametric methods. We derive a knowledge gradient policy with the locally parametric model, which maximizes the expected value of information. We show the policy is asymptotically optimal in theory, and experimental works suggests that the method can reliably find the optimal solution on a range of test functions. For the Markov decision processes problem class, we are motivated by an application where we want to co-optimize a battery for multiple revenue, in particular energy arbitrage and frequency regulation. The nature of this problem requires the battery to make charging and discharging decisions at different time scales while accounting for the stochastic information such as load demand, electricity prices, and regulation signals. Computing the exact optimal policy becomes intractable due to the large state space and the number of time steps. We propose two methods to circumvent the computation bottleneck. First, we propose a nested MDP model that structure the co-optimization problem into smaller sub-problems with reduced state space. This new model allows us to understand how the battery behaves down to the two-second dynamics (that of the frequency regulation market). Second, we introduce a low-rank value function approximation for backward dynamic programming. This new method only requires computing the exact value function for a small subset of the state space and approximate the entire value function via low-rank matrix completion. We test these methods on historical price data from the

  11. A Local Approach Methodology for the Analysis of Ultimate Strength ...

    African Journals Online (AJOL)

    The local approach methodology in contrast to classical fracture mechanics can be used to predict the onset of tearing fracture, and the effects of geometry in tubular joints. Finite element analysis of T-joints plate geometries, and tubular joints has been done. The parameters of constraint, equivalent stress, plastic strain and ...

  12. Local energy developments based on spatial and systemic approaches

    NARCIS (Netherlands)

    Manickam, Anu

    Local energy developments from a spatial and systemic approach are highlighted using examples from a Dutch case study. Developments in energy systems included interconnectedness of contextual factors and systems responses. The need to explore both the contextual factors and systemic aspects are

  13. Assessment of Constraint Effects based on Local Approach

    International Nuclear Information System (INIS)

    Lee, Tae Rin; Chang, Yoon Suk; Choi, Jae Boong; Seok, Chang Sung; Kim, Young Jin

    2005-01-01

    Traditional fracture mechanics has been used to ensure a structural integrity, in which the geometry independence is assumed in crack tip deformation and fracture toughness. However, the assumption is applicable only within limited conditions. To address fracture covering a broad range of loading and crack geometries, two-parameter global approach and local approach have been proposed. The two-parameter global approach can quantify the load and crack geometry effects by adopting T-stress or Q-parameter but time-consuming and expensive since lots of experiments and finite element (FE) analyses are necessary. On the other hand, the local approach evaluates the load and crack geometry effects based on damage model. Once material specific fitting constants are determined from a few experiments and FE analyses, the fracture resistance characteristics can be obtained by numerical simulation. The purpose of this paper is to investigate constraint effects for compact tension (CT) specimens with different in-plane or out-of-plane size using local approach. Both modified GTN model and Rousselier model are adopted to examine the ductile fracture behavior of SA515 Gr.60 carbon steel at high temperature. The fracture resistance (J-R) curves are estimated through numerical analysis, compared with corresponding experimental results and, then, crack length, thickness and side-groove effects are evaluated

  14. Local density approach to surfaces and adsorbed layers

    International Nuclear Information System (INIS)

    Wimmer, E.; Freeman, A.J.; Weinert, M.

    1986-01-01

    The authors show that the local density problem for the thin film geometry can be solved with high accuracy by employing the all-electron full-potential linearized augmented-plane-wave method. This is achieved by removing all shape approximations in the charge density and the potential and by using a highly flexible variational basis set. Also demonstrated is the fact that for a graphite monolayer, local density total energies give excellent descriptions of equilibrium geometries and discuss the overestimation of local-density cohesive energies due to an incomplete treatment of correlation effects in the free atom

  15. New Methods for Crafting Locally Decision-Relevant Scenarios

    Science.gov (United States)

    Lempert, R. J.

    2015-12-01

    Scenarios can play an important role in helping decision makers to imagine future worlds, both good and bad, different than the one with which we are familiar and to take concrete steps now to address the risks generated by climate change. At their best, scenarios can effectively represent deep uncertainty; integrate over multiple domains; and enable parties with different expectation and values to expand the range of futures they consider, to see the world from different points of view, and to grapple seriously with the potential implications of surprising or inconvenient futures. These attributes of scenario processes can prove crucial in helping craft effective responses to climate change. But traditional scenario methods can also fail to overcome difficulties related to choosing, communicating, and using scenarios to identify, evaluate, and reach consensus on appropriate policies. Such challenges can limit scenario's impact in broad public discourse. This talk will demonstrate how new decision support approaches can employ new quantitative tools that allow scenarios to emerge from a process of deliberation with analysis among stakeholders, rather than serve as inputs to it, thereby increasing the impacts of scenarios on decision making. This talk will demonstrate these methods in the design of a decision support tool to help residents of low lying coastal cities grapple with the long-term risks of sea level rise. In particular, this talk will show how information from the IPCC SSP's can be combined with local information to provide a rich set of locally decision-relevant information.

  16. Local Interaction Simulation Approach for Fault Detection in Medical Ultrasonic Transducers

    Directory of Open Access Journals (Sweden)

    Z. Hashemiyan

    2015-01-01

    Full Text Available A new approach is proposed for modelling medical ultrasonic transducers operating in air. The method is based on finite elements and the local interaction simulation approach. The latter leads to significant reductions of computational costs. Transmission and reception properties of the transducer are analysed using in-air reverberation patterns. The proposed approach can help to provide earlier detection of transducer faults and their identification, reducing the risk of misdiagnosis due to poor image quality.

  17. Evaluation of local corrosion life by statistical method

    International Nuclear Information System (INIS)

    Kato, Shunji; Kurosawa, Tatsuo; Takaku, Hiroshi; Kusanagi, Hideo; Hirano, Hideo; Kimura, Hideo; Hide, Koichiro; Kawasaki, Masayuki

    1987-01-01

    In this paper, for the purpose of achievement of life extension of light water reactor, we examined the evaluation of local corrosion by satistical method and its application of nuclear power plant components. There are many evaluation examples of maximum cracking depth of local corrosion by dowbly exponential distribution. This evaluation method has been established. But, it has not been established that we evaluate service lifes of construction materials by satistical method. In order to establish of service life evaluation by satistical method, we must strive to collect local corrosion dates and its analytical researchs. (author)

  18. A Parzen window-based approach for the detection of locally enriched transcription factor binding sites.

    Science.gov (United States)

    Vandenbon, Alexis; Kumagai, Yutaro; Teraguchi, Shunsuke; Amada, Karlou Mar; Akira, Shizuo; Standley, Daron M

    2013-01-21

    Identification of cis- and trans-acting factors regulating gene expression remains an important problem in biology. Bioinformatics analyses of regulatory regions are hampered by several difficulties. One is that binding sites for regulatory proteins are often not significantly over-represented in the set of DNA sequences of interest, because of high levels of false positive predictions, and because of positional restrictions on functional binding sites with regard to the transcription start site. We have developed a novel method for the detection of regulatory motifs based on their local over-representation in sets of regulatory regions. The method makes use of a Parzen window-based approach for scoring local enrichment, and during evaluation of significance it takes into account GC content of sequences. We show that the accuracy of our method compares favourably to that of other methods, and that our method is capable of detecting not only generally over-represented regulatory motifs, but also locally over-represented motifs that are often missed by standard motif detection approaches. Using a number of examples we illustrate the validity of our approach and suggest applications, such as the analysis of weaker binding sites. Our approach can be used to suggest testable hypotheses for wet-lab experiments. It has potential for future analyses, such as the prediction of weaker binding sites. An online application of our approach, called LocaMo Finder (Local Motif Finder), is available at http://sysimm.ifrec.osaka-u.ac.jp/tfbs/locamo/.

  19. The Approach of Local Firms towards E-Banking

    OpenAIRE

    MSc. Vjosa Mullatahiri; MSc. Lorik Abdullahu; MSc. Ganimete Podvorica

    2015-01-01

    There is a visible demand to increase the awareness for the efficacy and the advantages that e-banking has to offer to small enterprises; however, many other enterprises cannot conceive the possibility of running their business without e-banking. This study on approach of local firms towards e-banking is conducted by applying the Grounded Theory of Barney Glaser and Anselm Strauss and the Critical Incident Technique, in order to identify the factors influencing the satisfaction of the busines...

  20. Local Support Mechanisms for Entrepreneurship: The Approach of Local Development and Innovation Institutions

    Directory of Open Access Journals (Sweden)

    Katimertzopoulos, F.

    2017-03-01

    Full Text Available Purpose: The growth potential of SMEs entrepreneurship is examined at regional and local level, initially on a Global scale and then for the case of Greece. Additionally, the possibility of an economic development policy beyond the macroeconomic approach is examined, focusing on business growth and competitiveness in the light of meso and micro-economic policy approach. Design/methodology/approach: This research leads to the proposal of building knowledge mechanisms and direct and efficient systematic development and innovation at the local level, particularity during a time of economic crisis. The establishment of Institutes of Local Development and Innovation (ITAK is primarily geared towards promoting innovative entrepreneurship and extroversion of locally installed businesses. As part of the proposal for the establishment of ITAK, a questionnaire was developed - a tool to initially measure companies' opinions on the need for outside help in the macro, meso and micro environment, in order to demonstrate that ITAK local-level structures could be developed. Findings: The survey results were accrued via the analysis of questionnaires distributed to companies. The results of the questionnaires in the micro-environment in relation to those in the macro-environment shows a lower tendency to change business, which may be because managers perceive economics several times more in macroeconomic terms rather than in meso and micro economic (terms. Research limitations/implications: The restrictions of this particular research are the small sample of study of businesses in one country (Greece; this is because the approach of study, which is quantitative-qualitative, limits analysis to small data sets in the current phase. Originality/value: The results in the micro-environment, in relation to those at macro-environmental, shows a lower tendency to change business, something which may be because managers perceive economics several times more in

  1. Local Convergence and Radius of Convergence for Modified Newton Method

    Directory of Open Access Journals (Sweden)

    Măruşter Ştefan

    2017-12-01

    Full Text Available We investigate the local convergence of modified Newton method, i.e., the classical Newton method in which the derivative is periodically re-evaluated. Based on the convergence properties of Picard iteration for demicontractive mappings, we give an algorithm to estimate the local radius of convergence for considered method. Numerical experiments show that the proposed algorithm gives estimated radii which are very close to or even equal with the best ones.

  2. Climate change and local pollution effects. An integrated approach

    International Nuclear Information System (INIS)

    Aaheim, H.A.; Kristin, A.; Seip, H.M.

    1999-01-01

    Few studies on measures for mitigation of damage caused by man-made emissions to the environment have tried to consider all major effects. We illustrate the importance of an integrated approach by estimating costs and benefits of a proposed energy saving program for Hungary, originally designed to reduce CO 2 emissions. The dominant benefit of implementing the program is likely to be reduced health damage from local pollutants. Also reduced costs of material damage and to a lesser extent vegetation damage contribute to make the net benefit considerable. Compared to the reduction in these local and regional effects, the benefits from reducing greenhouse gases are likely to be minor. Since local effects in general occur much earlier after measures have been implemented than effects of increased emissions of greenhouse gases, inclusion of local effects makes evaluation of climate policy less dependent on the choice of discount rate. In our opinion, similar results are likely for many measures originally designed to reduce emissions of greenhouse gases particularly in some areas in developing countries with high local pollution levels. Main uncertainties in the analysis, e.g. in the relationships between damage and pollution level, are discussed. 72 refs

  3. Accounting for linkage disequilibrium in genome scans for selection without individual genotypes: The local score approach.

    Science.gov (United States)

    Fariello, María Inés; Boitard, Simon; Mercier, Sabine; Robelin, David; Faraut, Thomas; Arnould, Cécile; Recoquillay, Julien; Bouchez, Olivier; Salin, Gérald; Dehais, Patrice; Gourichon, David; Leroux, Sophie; Pitel, Frédérique; Leterrier, Christine; SanCristobal, Magali

    2017-07-01

    Detecting genomic footprints of selection is an important step in the understanding of evolution. Accounting for linkage disequilibrium in genome scans increases detection power, but haplotype-based methods require individual genotypes and are not applicable on pool-sequenced samples. We propose to take advantage of the local score approach to account for linkage disequilibrium in genome scans for selection, cumulating (possibly small) signals from single markers over a genomic segment, to clearly pinpoint a selection signal. Using computer simulations, we demonstrate that this approach detects selection with higher power than several state-of-the-art single-marker, windowing or haplotype-based approaches. We illustrate this on two benchmark data sets including individual genotypes, for which we obtain similar results with the local score and one haplotype-based approach. Finally, we apply the local score approach to Pool-Seq data obtained from a divergent selection experiment on behaviour in quail and obtain precise and biologically coherent selection signals: while competing methods fail to highlight any clear selection signature, our method detects several regions involving genes known to act on social responsiveness or autistic traits. Although we focus here on the detection of positive selection from multiple population data, the local score approach is general and can be applied to other genome scans for selection or other genomewide analyses such as GWAS. © 2017 John Wiley & Sons Ltd.

  4. Energy-Based Acoustic Source Localization Methods: A Survey

    Directory of Open Access Journals (Sweden)

    Wei Meng

    2017-02-01

    Full Text Available Energy-based source localization is an important problem in wireless sensor networks (WSNs, which has been studied actively in the literature. Numerous localization algorithms, e.g., maximum likelihood estimation (MLE and nonlinear-least-squares (NLS methods, have been reported. In the literature, there are relevant review papers for localization in WSNs, e.g., for distance-based localization. However, not much work related to energy-based source localization is covered in the existing review papers. Energy-based methods are proposed and specially designed for a WSN due to its limited sensor capabilities. This paper aims to give a comprehensive review of these different algorithms for energy-based single and multiple source localization problems, their merits and demerits and to point out possible future research directions.

  5. Geometrical optics in the near field: local plane-interface approach with evanescent waves.

    Science.gov (United States)

    Bose, Gaurav; Hyvärinen, Heikki J; Tervo, Jani; Turunen, Jari

    2015-01-12

    We show that geometrical models may provide useful information on light propagation in wavelength-scale structures even if evanescent fields are present. We apply a so-called local plane-wave and local plane-interface methods to study a geometry that resembles a scanning near-field microscope. We show that fair agreement between the geometrical approach and rigorous electromagnetic theory can be achieved in the case where evanescent waves are required to predict any transmission through the structure.

  6. Estimating the financial resources needed for local public health departments in Minnesota: a multimethod approach.

    Science.gov (United States)

    Riley, William; Briggs, Jill; McCullough, Mac

    2011-01-01

    This study presents a model for determining total funding needed for individual local health departments. The aim is to determine the financial resources needed to provide services for statewide local public health departments in Minnesota based on a gaps analysis done to estimate the funding needs. We used a multimethod analysis consisting of 3 approaches to estimate gaps in local public health funding consisting of (1) interviews of selected local public health leaders, (2) a Delphi panel, and (3) a Nominal Group Technique. On the basis of these 3 approaches, a consensus estimate of funding gaps was generated for statewide projections. The study includes an analysis of cost, performance, and outcomes from 2005 to 2007 for all 87 local governmental health departments in Minnesota. For each of the methods, we selected a panel to represent a profile of Minnesota health departments. The 2 main outcome measures were local-level gaps in financial resources and total resources needed to provide public health services at the local level. The total public health expenditure in Minnesota for local governmental public health departments was $302 million in 2007 ($58.92 per person). The consensus estimate of the financial gaps in local public health departments indicates that an additional $32.5 million (a 10.7% increase or $6.32 per person) is needed to adequately serve public health needs in the local communities. It is possible to make informed estimates of funding gaps for public health activities on the basis of a combination of quantitative methods. There is a wide variation in public health expenditure at the local levels, and methods are needed to establish minimum baseline expenditure levels to adequately treat a population. The gaps analysis can be used by stakeholders to inform policy makers of the need for improved funding of the public health system.

  7. Traditional methods of social control in Afikpo north local ...

    African Journals Online (AJOL)

    Traditional methods of social control in Afikpo north local government area, Ebonyi state south eastern Nigeria. ... Journal of Religion and Human Relations ... simple percentage was used in presenting and interpreting the quantitative data.

  8. An alternative subspace approach to EEG dipole source localization

    Science.gov (United States)

    Xu, Xiao-Liang; Xu, Bobby; He, Bin

    2004-01-01

    In the present study, we investigate a new approach to electroencephalography (EEG) three-dimensional (3D) dipole source localization by using a non-recursive subspace algorithm called FINES. In estimating source dipole locations, the present approach employs projections onto a subspace spanned by a small set of particular vectors (FINES vector set) in the estimated noise-only subspace instead of the entire estimated noise-only subspace in the case of classic MUSIC. The subspace spanned by this vector set is, in the sense of principal angle, closest to the subspace spanned by the array manifold associated with a particular brain region. By incorporating knowledge of the array manifold in identifying FINES vector sets in the estimated noise-only subspace for different brain regions, the present approach is able to estimate sources with enhanced accuracy and spatial resolution, thus enhancing the capability of resolving closely spaced sources and reducing estimation errors. The present computer simulations show, in EEG 3D dipole source localization, that compared to classic MUSIC, FINES has (1) better resolvability of two closely spaced dipolar sources and (2) better estimation accuracy of source locations. In comparison with RAP-MUSIC, FINES' performance is also better for the cases studied when the noise level is high and/or correlations among dipole sources exist.

  9. An alternative subspace approach to EEG dipole source localization

    International Nuclear Information System (INIS)

    Xu Xiaoliang; Xu, Bobby; He Bin

    2004-01-01

    In the present study, we investigate a new approach to electroencephalography (EEG) three-dimensional (3D) dipole source localization by using a non-recursive subspace algorithm called FINES. In estimating source dipole locations, the present approach employs projections onto a subspace spanned by a small set of particular vectors (FINES vector set) in the estimated noise-only subspace instead of the entire estimated noise-only subspace in the case of classic MUSIC. The subspace spanned by this vector set is, in the sense of principal angle, closest to the subspace spanned by the array manifold associated with a particular brain region. By incorporating knowledge of the array manifold in identifying FINES vector sets in the estimated noise-only subspace for different brain regions, the present approach is able to estimate sources with enhanced accuracy and spatial resolution, thus enhancing the capability of resolving closely spaced sources and reducing estimation errors. The present computer simulations show, in EEG 3D dipole source localization, that compared to classic MUSIC, FINES has (1) better resolvability of two closely spaced dipolar sources and (2) better estimation accuracy of source locations. In comparison with RAP-MUSIC, FINES' performance is also better for the cases studied when the noise level is high and/or correlations among dipole sources exist

  10. A Practical, Robust and Fast Method for Location Localization in Range-Based Systems.

    Science.gov (United States)

    Huang, Shiping; Wu, Zhifeng; Misra, Anil

    2017-12-11

    Location localization technology is used in a number of industrial and civil applications. Real time location localization accuracy is highly dependent on the quality of the distance measurements and efficiency of solving the localization equations. In this paper, we provide a novel approach to solve the nonlinear localization equations efficiently and simultaneously eliminate the bad measurement data in range-based systems. A geometric intersection model was developed to narrow the target search area, where Newton's Method and the Direct Search Method are used to search for the unknown position. Not only does the geometric intersection model offer a small bounded search domain for Newton's Method and the Direct Search Method, but also it can self-correct bad measurement data. The Direct Search Method is useful for the coarse localization or small target search domain, while the Newton's Method can be used for accurate localization. For accurate localization, by utilizing the proposed Modified Newton's Method (MNM), challenges of avoiding the local extrema, singularities, and initial value choice are addressed. The applicability and robustness of the developed method has been demonstrated by experiments with an indoor system.

  11. Multilevel local refinement and multigrid methods for 3-D turbulent flow

    Energy Technology Data Exchange (ETDEWEB)

    Liao, C.; Liu, C. [UCD, Denver, CO (United States); Sung, C.H.; Huang, T.T. [David Taylor Model Basin, Bethesda, MD (United States)

    1996-12-31

    A numerical approach based on multigrid, multilevel local refinement, and preconditioning methods for solving incompressible Reynolds-averaged Navier-Stokes equations is presented. 3-D turbulent flow around an underwater vehicle is computed. 3 multigrid levels and 2 local refinement grid levels are used. The global grid is 24 x 8 x 12. The first patch is 40 x 16 x 20 and the second patch is 72 x 32 x 36. 4th order artificial dissipation are used for numerical stability. The conservative artificial compressibility method are used for further improvement of convergence. To improve the accuracy of coarse/fine grid interface of local refinement, flux interpolation method for refined grid boundary is used. The numerical results are in good agreement with experimental data. The local refinement can improve the prediction accuracy significantly. The flux interpolation method for local refinement can keep conservation for a composite grid, therefore further modify the prediction accuracy.

  12. A Variational Level Set Approach Based on Local Entropy for Image Segmentation and Bias Field Correction.

    Science.gov (United States)

    Tang, Jian; Jiang, Xiaoliang

    2017-01-01

    Image segmentation has always been a considerable challenge in image analysis and understanding due to the intensity inhomogeneity, which is also commonly known as bias field. In this paper, we present a novel region-based approach based on local entropy for segmenting images and estimating the bias field simultaneously. Firstly, a local Gaussian distribution fitting (LGDF) energy function is defined as a weighted energy integral, where the weight is local entropy derived from a grey level distribution of local image. The means of this objective function have a multiplicative factor that estimates the bias field in the transformed domain. Then, the bias field prior is fully used. Therefore, our model can estimate the bias field more accurately. Finally, minimization of this energy function with a level set regularization term, image segmentation, and bias field estimation can be achieved. Experiments on images of various modalities demonstrated the superior performance of the proposed method when compared with other state-of-the-art approaches.

  13. MU-LOC: A Machine-Learning Method for Predicting Mitochondrially Localized Proteins in Plants

    DEFF Research Database (Denmark)

    Zhang, Ning; Rao, R Shyama Prasad; Salvato, Fernanda

    2018-01-01

    -sequence or a multitude of internal signals. Compared with experimental approaches, computational predictions provide an efficient way to infer subcellular localization of a protein. However, it is still challenging to predict plant mitochondrially localized proteins accurately due to various limitations. Consequently......, the performance of current tools can be improved with new data and new machine-learning methods. We present MU-LOC, a novel computational approach for large-scale prediction of plant mitochondrial proteins. We collected a comprehensive dataset of plant subcellular localization, extracted features including amino...

  14. Global and Local Sensitivity Analysis Methods for a Physical System

    Science.gov (United States)

    Morio, Jerome

    2011-01-01

    Sensitivity analysis is the study of how the different input variations of a mathematical model influence the variability of its output. In this paper, we review the principle of global and local sensitivity analyses of a complex black-box system. A simulated case of application is given at the end of this paper to compare both approaches.…

  15. Long-term adherence to a local guideline on postoperative body temperature measurement: mixed methods analysis

    NARCIS (Netherlands)

    Storm-Versloot, Marja N.; Knops, Anouk M.; Ubbink, Dirk T.; Goossens, Astrid; Legemate, Dink A.; Vermeulen, Hester

    2012-01-01

    Aim To find out whether a successful multifaceted implementation approach of a local evidence-based guideline on postoperative body temperature measurements (BTM) was persistent over time, and which factors influenced long-term adherence. Methods Mixed methods analysis. Patient records were

  16. A novel approach for the global localization problem

    Directory of Open Access Journals (Sweden)

    Abraham Sánchez

    2012-03-01

    Full Text Available Este artículo describe una metodología de planificación, localización y mapeo simultáneos enfocada en el problema de localización global, el robot explora el ambiente eficientemente y también considera los requisitos de un algoritmo de localización y mapeo simultáneos. El método está basado en la generación aleatoria incremental de una estructura de datos llamada árbol aleatorio basado en sensores, la cual representa un mapa de caminos del área explorada con su región segura asociada. Un procedimiento de localización continuo basado encaracterísticas B-splines de la región segura se integró en el esquema.This paper describes a simultaneous planning localization and mapping (SPLAM methodology focussed on the global localization problem, where the robot explores the environment efficiently and also considers the requisites of the simultaneous localization and mapping algorithm. The method is based on the randomized incremental generation of a data structure called Sensor-based Random Tree, which represents a roadmap of the explored area with an associated safe region. A continuous localization procedure based on B-Splines features of the safe region is integrated in the scheme.

  17. Localization of a Vehicle: A Dynamic Interval Constraint Satisfaction Problem-Based Approach

    Directory of Open Access Journals (Sweden)

    Kangni Kueviakoe

    2018-01-01

    Full Text Available This paper introduces a new interval constraint propagation (ICP approach dealing with the real-time vehicle localization problem. Bayesian methods like extended Kalman filter (EKF are classically used to achieve vehicle localization. ICP is an alternative which provides guaranteed localization results rather than probabilities. Our approach assumes that all models and measurement errors are bounded within known limits without any other hypotheses on the probability distribution. The proposed algorithm uses a low-level consistency algorithm and has been validated with an outdoor vehicle equipped with a GPS receiver, a gyro, and odometers. Results have been compared to EKF and other ICP methods such as hull consistency (HC4 and 3-bound (3B algorithms. Both consistencies of EKF and our algorithm have been experimentally studied.

  18. Non-local currents in 2D QFT: an alternative To - the quantum inverse scattering method

    International Nuclear Information System (INIS)

    Bernard, D.; Leclair, A.; Cornell Univ., Ithaca, NY

    1990-01-01

    The formalism based on non-local charges that we propose provides an alternative to the quantum inverse scattering method for solving integrable quantum field theories in 2D. The content of the paper is: 1. Introduction: historical background. 2. The NLC approach to 2D QFT: a summary. 3 Exchange algebras and on-shell conservation laws: why non-local charges are useful. 4. The lattice construction: the geometrical origin of non-local conserved currents. 5. The continuum construction: how to deal with non-local conserved currents. 6. Examples: Yangian and quantum group currents. 7 Conclusions: open problems. 22 refs., 4 figs

  19. Maintenance Approaches for Different Production Methods

    Directory of Open Access Journals (Sweden)

    Mungani, Dzivhuluwani Simon

    2013-11-01

    Full Text Available Various production methods are used in industry to manufacture or produce a variety of products needed by industry and consumers. The nature of a product determines which production method is most suitable or cost-effective. A continuous process is typically used to produce large volumes of liquids or gases. Batch processing is often used for small volumes, such as pharmaceutical products. This paper discusses a research project to determine the relationship between maintenance approaches and production methods. A survey was done to determine to what extent three maintenance approaches reliability-centred maintenance (RCM, total productive maintenance (TPM, and business-centred maintenance (BCM are used for three different processing methods (continuous process, batch process, and a production line method.

  20. Socratic Method as an Approach to Teaching

    Directory of Open Access Journals (Sweden)

    Haris Delić

    2016-10-01

    Full Text Available In this article we presented the theoretical view of Socrates' life and his method in teaching. After the biographical facts of Socrates and his life, we explained the method he used in teaching and the two main types of his method, Classic and Modern Socratic Method. Since the core of Socrates' approach is the dialogue as a form of teaching we explained how exactly the Socratic dialogue goes. Besides that, we presented two examples of dialogues that Socrates led, Meno and Gorgias. Socratic circle is also one of the aspects that we presented in this paper. It is the form of seminars that is crucial for group discussions of a given theme. At the end, some disadvantages of the Method are explained. With this paper, the reader can get the conception of this approach of teaching and can use Socrates as an example of how successfull teacher leads his students towards the goal.

  1. Measuring Filament Orientation: A New Quantitative, Local Approach

    Energy Technology Data Exchange (ETDEWEB)

    Green, C.-E.; Cunningham, M. R.; Jones, P. A. [School of Physics, University of New South Wales, Sydney, NSW, 2052 (Australia); Dawson, J. R. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710 (Australia); Novak, G. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Fissel, L. M. [National Radio Astronomy Observatory (NRAO), 520 Edgemont Road, Charlottesville, VA, 22903 (United States)

    2017-09-01

    The relative orientation between filamentary structures in molecular clouds and the ambient magnetic field provides insight into filament formation and stability. To calculate the relative orientation, a measurement of filament orientation is first required. We propose a new method to calculate the orientation of the one-pixel-wide filament skeleton that is output by filament identification algorithms such as filfinder. We derive the local filament orientation from the direction of the intensity gradient in the skeleton image using the Sobel filter and a few simple post-processing steps. We call this the “Sobel-gradient method.” The resulting filament orientation map can be compared quantitatively on a local scale with the magnetic field orientation map to then find the relative orientation of the filament with respect to the magnetic field at each point along the filament. It can also be used for constructing radial profiles for filament width fitting. The proposed method facilitates automation in analyses of filament skeletons, which is imperative in this era of “big data.”.

  2. Measuring Filament Orientation: A New Quantitative, Local Approach

    Science.gov (United States)

    Green, C.-E.; Dawson, J. R.; Cunningham, M. R.; Jones, P. A.; Novak, G.; Fissel, L. M.

    2017-09-01

    The relative orientation between filamentary structures in molecular clouds and the ambient magnetic field provides insight into filament formation and stability. To calculate the relative orientation, a measurement of filament orientation is first required. We propose a new method to calculate the orientation of the one-pixel-wide filament skeleton that is output by filament identification algorithms such as filfinder. We derive the local filament orientation from the direction of the intensity gradient in the skeleton image using the Sobel filter and a few simple post-processing steps. We call this the “Sobel-gradient method.” The resulting filament orientation map can be compared quantitatively on a local scale with the magnetic field orientation map to then find the relative orientation of the filament with respect to the magnetic field at each point along the filament. It can also be used for constructing radial profiles for filament width fitting. The proposed method facilitates automation in analyses of filament skeletons, which is imperative in this era of “big data.”

  3. Measuring Filament Orientation: A New Quantitative, Local Approach

    International Nuclear Information System (INIS)

    Green, C.-E.; Cunningham, M. R.; Jones, P. A.; Dawson, J. R.; Novak, G.; Fissel, L. M.

    2017-01-01

    The relative orientation between filamentary structures in molecular clouds and the ambient magnetic field provides insight into filament formation and stability. To calculate the relative orientation, a measurement of filament orientation is first required. We propose a new method to calculate the orientation of the one-pixel-wide filament skeleton that is output by filament identification algorithms such as filfinder. We derive the local filament orientation from the direction of the intensity gradient in the skeleton image using the Sobel filter and a few simple post-processing steps. We call this the “Sobel-gradient method.” The resulting filament orientation map can be compared quantitatively on a local scale with the magnetic field orientation map to then find the relative orientation of the filament with respect to the magnetic field at each point along the filament. It can also be used for constructing radial profiles for filament width fitting. The proposed method facilitates automation in analyses of filament skeletons, which is imperative in this era of “big data.”

  4. 广西地方院校大学生多元文化素质培养途径与方法探讨%Discussion on Approaches and Methods for Multicultural Quality Training of Guangxi Local College Students

    Institute of Scientific and Technical Information of China (English)

    吴声军

    2012-01-01

    In the context of CAFTA,Guangxi local colleges should exert their advantages and features,building the multicultural curriculum system,developing multiculturalism quality teachers, building a national mutual respect and recognition of university culture, implementing various forms of multicultural classroom teaching and strengthening international cooperation exchanges and other methods to strengthen the multicultural education of all ethnic groups in Guangxi and ASEAN countries multicultural education, To enhance the multicultural quality of college students and cultivate the high-quality international talents.%面对CAFTA的背景,广西地方院校应该发挥自身的优势和特点。通过构建多元文化课程体系、培养合理的师资队伍、建设民族互尊与认同的校园文化、实施形式多样的多元文化课堂教学以及加强国际合作交流等途径和方法,加强广西各民族与东盟各国多元文化教育,全面提升在校大学生多元文化素质,培养高素质的国际化人才。

  5. Evaluation and comparison of mammalian subcellular localization prediction methods

    Directory of Open Access Journals (Sweden)

    Fink J Lynn

    2006-12-01

    Full Text Available Abstract Background Determination of the subcellular location of a protein is essential to understanding its biochemical function. This information can provide insight into the function of hypothetical or novel proteins. These data are difficult to obtain experimentally but have become especially important since many whole genome sequencing projects have been finished and many resulting protein sequences are still lacking detailed functional information. In order to address this paucity of data, many computational prediction methods have been developed. However, these methods have varying levels of accuracy and perform differently based on the sequences that are presented to the underlying algorithm. It is therefore useful to compare these methods and monitor their performance. Results In order to perform a comprehensive survey of prediction methods, we selected only methods that accepted large batches of protein sequences, were publicly available, and were able to predict localization to at least nine of the major subcellular locations (nucleus, cytosol, mitochondrion, extracellular region, plasma membrane, Golgi apparatus, endoplasmic reticulum (ER, peroxisome, and lysosome. The selected methods were CELLO, MultiLoc, Proteome Analyst, pTarget and WoLF PSORT. These methods were evaluated using 3763 mouse proteins from SwissProt that represent the source of the training sets used in development of the individual methods. In addition, an independent evaluation set of 2145 mouse proteins from LOCATE with a bias towards the subcellular localization underrepresented in SwissProt was used. The sensitivity and specificity were calculated for each method and compared to a theoretical value based on what might be observed by random chance. Conclusion No individual method had a sufficient level of sensitivity across both evaluation sets that would enable reliable application to hypothetical proteins. All methods showed lower performance on the LOCATE

  6. The Approach of Local Firms towards E-Banking

    Directory of Open Access Journals (Sweden)

    MSc. Vjosa Mullatahiri

    2015-06-01

    Full Text Available There is a visible demand to increase the awareness for the efficacy and the advantages that e-banking has to offer to small enterprises; however, many other enterprises cannot conceive the possibility of running their business without e-banking. This study on approach of local firms towards e-banking is conducted by applying the Grounded Theory of Barney Glaser and Anselm Strauss and the Critical Incident Technique, in order to identify the factors influencing the satisfaction of the business clients when using e-banking services. The empirical data were gathered through interviews. Factual findings establish the foundation for a more extended research aiming to reveal the satisfaction of the business clients with service of e-banking, simultaneously exploring opportunities which banks have to adopt in order to succeed in attracting and retaining the business clients.

  7. Prediction of welding residual distortions of large structures using a local/global approach

    International Nuclear Information System (INIS)

    Duan, Y. G.; Bergheau, J. M.; Vincent, Y.; Boitour, F.; Leblond, J. B.

    2007-01-01

    Prediction of welding residual distortions is more difficult than that of the microstructure and residual stresses. On the one hand, a fine mesh (often 3D) has to be used in the heat affected zone for the sake of the sharp variations of thermal, metallurgical and mechanical fields in this region. On the other hand, the whole structure is required to be meshed for the calculation of residual distortions. But for large structures, a 3D mesh is inconceivable caused by the costs of the calculation. Numerous methods have been developed to reduce the size of models. A local/global approach has been proposed to determine the welding residual distortions of large structures. The plastic strains and the microstructure due to welding are supposed can be determined from a local 3D model which concerns only the weld and its vicinity. They are projected as initial strains into a global 3D model which consists of the whole structure and obviously much less fine in the welded zone than the local model. The residual distortions are then calculated using a simple elastic analysis, which makes this method particularly effective in an industrial context. The aim of this article is to present the principle of the local/global approach then show the capacity of this method in an industrial context and finally study the definition of the local model

  8. Local coding based matching kernel method for image classification.

    Directory of Open Access Journals (Sweden)

    Yan Song

    Full Text Available This paper mainly focuses on how to effectively and efficiently measure visual similarity for local feature based representation. Among existing methods, metrics based on Bag of Visual Word (BoV techniques are efficient and conceptually simple, at the expense of effectiveness. By contrast, kernel based metrics are more effective, but at the cost of greater computational complexity and increased storage requirements. We show that a unified visual matching framework can be developed to encompass both BoV and kernel based metrics, in which local kernel plays an important role between feature pairs or between features and their reconstruction. Generally, local kernels are defined using Euclidean distance or its derivatives, based either explicitly or implicitly on an assumption of Gaussian noise. However, local features such as SIFT and HoG often follow a heavy-tailed distribution which tends to undermine the motivation behind Euclidean metrics. Motivated by recent advances in feature coding techniques, a novel efficient local coding based matching kernel (LCMK method is proposed. This exploits the manifold structures in Hilbert space derived from local kernels. The proposed method combines advantages of both BoV and kernel based metrics, and achieves a linear computational complexity. This enables efficient and scalable visual matching to be performed on large scale image sets. To evaluate the effectiveness of the proposed LCMK method, we conduct extensive experiments with widely used benchmark datasets, including 15-Scenes, Caltech101/256, PASCAL VOC 2007 and 2011 datasets. Experimental results confirm the effectiveness of the relatively efficient LCMK method.

  9. Improving the local wavenumber method by automatic DEXP transformation

    Science.gov (United States)

    Abbas, Mahmoud Ahmed; Fedi, Maurizio; Florio, Giovanni

    2014-12-01

    In this paper we present a new method for source parameter estimation, based on the local wavenumber function. We make use of the stable properties of the Depth from EXtreme Points (DEXP) method, in which the depth to the source is determined at the extreme points of the field scaled with a power-law of the altitude. Thus the method results particularly suited to deal with local wavenumber of high-order, as it is able to overcome its known instability caused by the use of high-order derivatives. The DEXP transformation enjoys a relevant feature when applied to the local wavenumber function: the scaling-law is in fact independent of the structural index. So, differently from the DEXP transformation applied directly to potential fields, the Local Wavenumber DEXP transformation is fully automatic and may be implemented as a very fast imaging method, mapping every kind of source at the correct depth. Also the simultaneous presence of sources with different homogeneity degree can be easily and correctly treated. The method was applied to synthetic and real examples from Bulgaria and Italy and the results agree well with known information about the causative sources.

  10. An online substructure identification method for local structural health monitoring

    International Nuclear Information System (INIS)

    Hou, Jilin; Ou, Jinping; Jankowski, Łukasz

    2013-01-01

    This paper proposes a substructure isolation method, which uses time series of measured local response for online monitoring of substructures. The proposed monitoring process consists of two key steps: construction of the isolated substructure, and its identification. The isolated substructure is an independent virtual structure, which is numerically isolated from the global structure by placing virtual supports on the interface. First, the isolated substructure is constructed by a specific linear combination of time series of its measured local responses. Then, the isolated substructure is identified using its local natural frequencies extracted from the combined responses. The substructure is assumed to be linear; the outside part of the global structure can have any characteristics. The method has no requirements on the initial state of the structure, and so the process can be carried out repetitively for online monitoring. Online isolation and monitoring is illustrated in a numerical example with a frame model, and then verified in a cantilever beam experiment. (paper)

  11. On the applicability of local approaches for the determination of the failure behavior of ductile steels

    International Nuclear Information System (INIS)

    Kussmaul, K.; Eisele, U.; Seidenfuss, M.

    1992-01-01

    The strength and deformation behavior of specimens and components is, on one hand, influenced by the local state of stress and strain and, on the other hand by the chemical composition and the microstructure of the material used. Using two different steels it was investigated in how far it is possible to predict the failure behavior of specimens and components qualitatively and quantitatively by means of local approaches. For this purpose two methods differing considerably from the basic idea were chosen. For the description of the failure behavior so-called damage models were used. These damage models try to describe numerically the process developing microscopically and finally leading to fracture by means of continuum mechanical approaches in order to calculate the macroscopical failure behavior. The results show that for ductile materials the damage models allow a very accurate calculation of smooth and notched specimens and components. The efforts presently required for the calculation are however still very high. Analyses using fracture mechanics approaches (J-Integral) in combination with the local stress states (multiaxiality) were performed to describe the failure behavior. With this approach it was tried to calculate crack initiation and maximum load of precracked specimens and components. The fracture mechanics methods are to be preferred for cracked components if an engineering estimation of crack initiation and maximum load is required only, since the calculational efforts of the fracture mechanics methods are much lower than those of the damage models

  12. Permutation statistical methods an integrated approach

    CERN Document Server

    Berry, Kenneth J; Johnston, Janis E

    2016-01-01

    This research monograph provides a synthesis of a number of statistical tests and measures, which, at first consideration, appear disjoint and unrelated. Numerous comparisons of permutation and classical statistical methods are presented, and the two methods are compared via probability values and, where appropriate, measures of effect size. Permutation statistical methods, compared to classical statistical methods, do not rely on theoretical distributions, avoid the usual assumptions of normality and homogeneity of variance, and depend only on the data at hand. This text takes a unique approach to explaining statistics by integrating a large variety of statistical methods, and establishing the rigor of a topic that to many may seem to be a nascent field in statistics. This topic is new in that it took modern computing power to make permutation methods available to people working in the mainstream of research. This research monograph addresses a statistically-informed audience, and can also easily serve as a ...

  13. A special purpose knowledge-based face localization method

    Science.gov (United States)

    Hassanat, Ahmad; Jassim, Sabah

    2008-04-01

    This paper is concerned with face localization for visual speech recognition (VSR) system. Face detection and localization have got a great deal of attention in the last few years, because it is an essential pre-processing step in many techniques that handle or deal with faces, (e.g. age, face, gender, race and visual speech recognition). We shall present an efficient method for localization human's faces in video images captured on mobile constrained devices, under a wide variation in lighting conditions. We use a multiphase method that may include all or some of the following steps starting with image pre-processing, followed by a special purpose edge detection, then an image refinement step. The output image will be passed through a discrete wavelet decomposition procedure, and the computed LL sub-band at a certain level will be transformed into a binary image that will be scanned by using a special template to select a number of possible candidate locations. Finally, we fuse the scores from the wavelet step with scores determined by color information for the candidate location and employ a form of fuzzy logic to distinguish face from non-face locations. We shall present results of large number of experiments to demonstrate that the proposed face localization method is efficient and achieve high level of accuracy that outperforms existing general-purpose face detection methods.

  14. New approach to local anodic oxidation of semiconductor heterostructures

    International Nuclear Information System (INIS)

    Martaus, Jozef; Gregusova, Dagmar; Cambel, Vladimir; Kudela, Robert; Soltys, Jan

    2008-01-01

    We have experimentally explored a new approach to local anodic oxidation (LAO) of a semiconductor heterostructures by means of atomic force microscopy (AFM). We have applied LAO to an InGaP/AlGaAs/GaAs heterostructure. Although LAO is usually applied to oxidize GaAs/AlGaAs/GaAs-based heterostructures, the use of the InGaP/AlGaAs/GaAs system is more advantageous. The difference lies in the use of different cap layer materials: Unlike GaAs, InGaP acts like a barrier material with respect to the underlying AlGaAs layer and has almost one order of magnitude lower density of surface states than GaAs. Consequently, the InGaP/AlGaAs/GaAs heterostructure had the remote Si-δ doping layer only 6.5 nm beneath the surface and the two-dimensional electron gas (2DEG) was confined only 23.5 nm beneath the surface. Moreover, InGaP unaffected by LAO is a very durable material in various etchants and allows us to repeatedly remove thin portions of the underlying AlGaAs layer via wet etching. This approach influences LAO technology fundamentally: LAO was used only to oxidize InGaP cap layer to define very narrow (∼50 nm) patterns. Subsequent wet etching was used to form very narrow and high-energy barriers in the 2DEG patterns. This new approach is promising for the development of future nano-devices operated both at low and high temperatures

  15. Measuring local autonomy: A decision-making approach

    NARCIS (Netherlands)

    Fleurke, F.; Willemse, R.

    2006-01-01

    In studies on central-local relations it is common to assess local autonomy in a deductive way. The extent of local autonomy is determined by measuring the central legal and financial competence, after which the remaining room for local decision-making is determined. The outcome of this indirect

  16. Ex-post evaluation of local energy efficiency and demand-side management operations - State of the art, bottom-up methods, applied examples and approach for the development of an evaluation practical culture; L'evaluation ex-post des operations locales de maitrise de la demande en energie - Etat de l'art, methodes bottom-up, exemples appliques et approche du developpement d'une culture pratique de l'evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Broc, J S

    2006-12-15

    Energy end-use Efficiency (EE) is a priority for energy policies to face resources exhaustion and to reduce pollutant emissions. At the same time, in France, local level is increasingly involved into the implementation of EE activities, whose frame is changing (energy market liberalization, new policy instruments). Needs for ex-post evaluation of the local EE activities are thus increasing, for regulation requirements and to support a necessary change of scale. Our thesis focuses on the original issue of the ex-post evaluation of local EE operations in France. The state of the art, through the analysis of the American and European experiences and of the reference guidebooks, gives a substantial methodological material and emphasises the key evaluation issues. Concurrently, local EE operations in France are characterized by an analysis of their environment and a work on their segmentation criteria. The combination of these criteria with the key evaluation issues provides an analysis framework used as the basis for the composition of evaluation methods. This also highlights the specific evaluation needs for local operations. A methodology is then developed to complete and adapt the existing material to design evaluation methods for local operations, so that stakeholders can easily appropriate. Evaluation results thus feed a know-how building process with experience feedback. These methods are to meet two main goals: to determine the operation results, and to detect the success/failure factors. The methodology was validated on concrete cases, where these objectives were reached. (author)

  17. Ex-post evaluation of local energy efficiency and demand-side management operations - State of the art, bottom-up methods, applied examples and approach for the development of an evaluation practical culture; L'evaluation ex-post des operations locales de maitrise de la demande en energie - Etat de l'art, methodes bottom-up, exemples appliques et approche du developpement d'une culture pratique de l'evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Broc, J.S

    2006-12-15

    Energy end-use Efficiency (EE) is a priority for energy policies to face resources exhaustion and to reduce pollutant emissions. At the same time, in France, local level is increasingly involved into the implementation of EE activities, whose frame is changing (energy market liberalization, new policy instruments). Needs for ex-post evaluation of the local EE activities are thus increasing, for regulation requirements and to support a necessary change of scale. Our thesis focuses on the original issue of the ex-post evaluation of local EE operations in France. The state of the art, through the analysis of the American and European experiences and of the reference guidebooks, gives a substantial methodological material and emphasises the key evaluation issues. Concurrently, local EE operations in France are characterized by an analysis of their environment and a work on their segmentation criteria. The combination of these criteria with the key evaluation issues provides an analysis framework used as the basis for the composition of evaluation methods. This also highlights the specific evaluation needs for local operations. A methodology is then developed to complete and adapt the existing material to design evaluation methods for local operations, so that stakeholders can easily appropriate. Evaluation results thus feed a know-how building process with experience feedback. These methods are to meet two main goals: to determine the operation results, and to detect the success/failure factors. The methodology was validated on concrete cases, where these objectives were reached. (author)

  18. An integrated approach to model strain localization bands in magnesium alloys

    Science.gov (United States)

    Baxevanakis, K. P.; Mo, C.; Cabal, M.; Kontsos, A.

    2018-02-01

    Strain localization bands (SLBs) that appear at early stages of deformation of magnesium alloys have been recently associated with heterogeneous activation of deformation twinning. Experimental evidence has demonstrated that such "Lüders-type" band formations dominate the overall mechanical behavior of these alloys resulting in sigmoidal type stress-strain curves with a distinct plateau followed by pronounced anisotropic hardening. To evaluate the role of SLB formation on the local and global mechanical behavior of magnesium alloys, an integrated experimental/computational approach is presented. The computational part is developed based on custom subroutines implemented in a finite element method that combine a plasticity model with a stiffness degradation approach. Specific inputs from the characterization and testing measurements to the computational approach are discussed while the numerical results are validated against such available experimental information, confirming the existence of load drops and the intensification of strain accumulation at the time of SLB initiation.

  19. A study of fatigue life prediction for automotive spot weldment using local strain approach

    International Nuclear Information System (INIS)

    Lee, Song In; Yu, Hyo Sun; Na, Sung Hun; Na, Eui Gyun

    2000-01-01

    The fatigue crack initiation life is studied on automotive spot weldment made from cold rolled carbon steel(SPC) sheet by using DCPDM and local strain approach. It can be found that the fatigue crack initiation behavior in spot weldment can be definitely detected by DCPDM system. The local stresses and strains are estimated by elastic-plastic FEM analysis and the alternative approximate method based on Neuber's rule were applied to predict the fatigue life of spot weldment. A satisfactory correlation between the predicted life and experimental life can be found in spot weldment within a factor of 4

  20. Localization of sources of the hyperinsulinism through the image methods

    International Nuclear Information System (INIS)

    Abath, C.G.A.

    1990-01-01

    Pancreatic insulinomas are small tumours, manifested early by the high hormonal production. Microscopic changes, like islet cell hyperplasia or nesidioblastosis, are also sources of hyperinsulinism. The pre-operative localization of the lesions is important, avoiding unnecessary or insufficient blind pancreatectomies. It is presented the experience with 26 patients with hyperinsulinism, of whom six were examined by ultrasound, nine by computed tomography, 25 by angiography and 16 by pancreatic venous sampling for hormone assay, in order to localize the lesions. Percutaneous transhepatic portal and pancreatic vein catheterization with measurement of insuline concentrations was the most reliable and sensitive method for detecting the lesions, including those non-palpable during the surgical exploration (author)

  1. Modeling amorphization of tetrahedral structures under local approaches

    International Nuclear Information System (INIS)

    Jesurum, C.E.; Pulim, V.; Berger, B.; Hobbs, L.W.

    1997-01-01

    Many crystalline ceramics can be topologically disordered (amorphized) by disordering radiation events involving high-energy collision cascades or (in some cases) successive single-atom displacements. The authors are interested in both the potential for disorder and the possible aperiodic structures adopted following the disordering event. The potential for disordering is related to connectivity, and among those structures of interest are tetrahedral networks (such as SiO 2 , SiC and Si 3 N 4 ) comprising corner-shared tetrahedral units whose connectivities are easily evaluated. In order to study the response of these networks to radiation, the authors have chosen to model their assembly according to the (simple) local rules that each corner obeys in connecting to another tetrahedron; in this way they easily erect large computer models of any crystalline polymorphic form. Amorphous structures can be similarly grown by application of altered rules. They have adopted a simple model of irradiation in which all bonds in the neighborhood of a designated tetrahedron are destroyed, and they reform the bonds in this region according to a set of (possibly different) local rules appropriate to the environmental conditions. When a tetrahedron approaches the boundary of this neighborhood, it undergoes an optimization step in which a spring is inserted between two corners of compatible tetrahedra when they are within a certain distance of one another; component forces are then applied that act to minimize the distance between these corners and minimize the deviation from the rules. The resulting structure is then analyzed for the complete adjacency matrix, irreducible ring statistics, and bond angle distributions

  2. A method for spatially resolved local intracellular mechanochemical sensing and organelle manipulation

    NARCIS (Netherlands)

    Shekhar, S.; Cambi, A.; Figdor, Carl; Subramaniam, Vinod; Kanger, Johannes S.

    2012-01-01

    Because both the chemical and mechanical properties of living cells play crucial functional roles, there is a strong need for biophysical methods to address these properties simultaneously. Here we present a novel (to our knowledge) approach to measure local intracellular micromechanical and

  3. A method for spatially resolved local intracellular mechanochemical sensing and organelle manipulation.

    NARCIS (Netherlands)

    Shekhar, S.; Cambi, A.; Figdor, C.G.; Subramaniam, V.; Kanger, J.S.

    2012-01-01

    Because both the chemical and mechanical properties of living cells play crucial functional roles, there is a strong need for biophysical methods to address these properties simultaneously. Here we present a novel (to our knowledge) approach to measure local intracellular micromechanical and

  4. Modelling of bow-tie microstrip antennas using modified locally conformal FDTD method

    NARCIS (Netherlands)

    George, J.

    2000-01-01

    An analysis of bow-tie microstrip antennas is presented based on the use of the modified locally conformal finite-difference time-domain (FDTD) method. This approach enables the number of cells along the antenna length and width to be chosen independently of the antenna central width, which helps to

  5. A novel local learning based approach with application to breast cancer diagnosis

    Science.gov (United States)

    Xu, Songhua; Tourassi, Georgia

    2012-03-01

    In this paper, we introduce a new local learning based approach and apply it for the well-studied problem of breast cancer diagnosis using BIRADS-based mammographic features. To learn from our clinical dataset the latent relationship between these features and the breast biopsy result, our method first dynamically partitions the whole sample population into multiple sub-population groups through stochastically searching the sample population clustering space. Each encountered clustering scheme in our online searching process is then used to create a certain sample population partition plan. For every resultant sub-population group identified according to a partition plan, our method then trains a dedicated local learner to capture the underlying data relationship. In our study, we adopt the linear logistic regression model as our local learning method's base learner. Such a choice is made both due to the well-understood linear nature of the problem, which is compellingly revealed by a rich body of prior studies, and the computational efficiency of linear logistic regression--the latter feature allows our local learning method to more effectively perform its search in the sample population clustering space. Using a database of 850 biopsy-proven cases, we compared the performance of our method with a large collection of publicly available state-of-the-art machine learning methods and successfully demonstrated its performance advantage with statistical significance.

  6. LOCAL PUBLIC 0 EXPENDITURE AUTONOMY – MEASURING APPROACH

    Directory of Open Access Journals (Sweden)

    Irina BILAN

    2013-06-01

    Full Text Available The decentralization process was continuous in Romania starting with 1990, generating the implication of local authorities in local public finance, as a result of exclusives, shared and delegate competences and, so, the necessity of ensuring a good management of resources and expenditures. Therefore, the decentralization of competences / responsibilities from State to local governments was a major Romanian political theme and a first rank component of management of local public finance, as main driving instrument for local development. Specific legal framework of local responsibilities is established both to European and national level. Researchers based on regulation and practice have tried to quantify the responsibilities developing different models to measure local revenue and expenditures autonomy. The paper aims is to identify some models for measuring local expenditure autonomy and to apply for Romania. The study is oriented to measure local expenditure autonomy in Romania using Bell, Ebel, Kaiser and Rojchaichainthorn's model.

  7. A Hartree–Fock study of the confined helium atom: Local and global basis set approaches

    Energy Technology Data Exchange (ETDEWEB)

    Young, Toby D., E-mail: tyoung@ippt.pan.pl [Zakład Metod Komputerowych, Instytut Podstawowych Prolemów Techniki Polskiej Akademia Nauk, ul. Pawińskiego 5b, 02-106 Warszawa (Poland); Vargas, Rubicelia [Universidad Autónoma Metropolitana Iztapalapa, División de Ciencias Básicas e Ingenierías, Departamento de Química, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, D.F. C.P. 09340, México (Mexico); Garza, Jorge, E-mail: jgo@xanum.uam.mx [Universidad Autónoma Metropolitana Iztapalapa, División de Ciencias Básicas e Ingenierías, Departamento de Química, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, D.F. C.P. 09340, México (Mexico)

    2016-02-15

    Two different basis set methods are used to calculate atomic energy within Hartree–Fock theory. The first is a local basis set approach using high-order real-space finite elements and the second is a global basis set approach using modified Slater-type orbitals. These two approaches are applied to the confined helium atom and are compared by calculating one- and two-electron contributions to the total energy. As a measure of the quality of the electron density, the cusp condition is analyzed. - Highlights: • Two different basis set methods for atomic Hartree–Fock theory. • Galerkin finite element method and modified Slater-type orbitals. • Confined atom model (helium) under small-to-extreme confinement radii. • Detailed analysis of the electron wave-function and the cusp condition.

  8. Fluctuating local field method probed for a description of small classical correlated lattices

    Science.gov (United States)

    Rubtsov, Alexey N.

    2018-05-01

    Thermal-equilibrated finite classical lattices are considered as a minimal model of the systems showing an interplay between low-energy collective fluctuations and single-site degrees of freedom. Standard local field approach, as well as classical limit of the bosonic DMFT method, do not provide a satisfactory description of Ising and Heisenberg small lattices subjected to an external polarizing field. We show that a dramatic improvement can be achieved within a simple approach, in which the local field appears to be a fluctuating quantity related to the low-energy degree(s) of freedom.

  9. Simulation-Based Approach for Studying the Balancing of Local Smart Grids with Electric Vehicle Batteries

    Directory of Open Access Journals (Sweden)

    Juhani Latvakoski

    2015-07-01

    Full Text Available Modern society is facing great challenges due to pollution and increased carbon dioxide (CO2 emissions. As part of solving these challenges, the use of renewable energy sources and electric vehicles (EVs is rapidly increasing. However, increased dynamics have triggered problems in balancing energy supply and consumption demand in the power systems. The resulting uncertainty and unpredictability of energy production, consumption, and management of peak loads has caused an increase in costs for energy market actors. Therefore, the means for studying the balancing of local smart grids with EVs is a starting point for this paper. The main contribution is a simulation-based approach which was developed to enable the study of the balancing of local distribution grids with EV batteries in a cost-efficient manner. The simulation-based approach is applied to enable the execution of a distributed system with the simulation of a local distribution grid, including a number of charging stations and EVs. A simulation system has been constructed to support the simulation-based approach. The evaluation has been carried out by executing the scenario related to balancing local distribution grids with EV batteries in a step-by-step manner. The evaluation results indicate that the simulation-based approach is able to facilitate the evaluation of smart grid– and EV-related communication protocols, control algorithms for charging, and functionalities of local distribution grids as part of a complex, critical cyber-physical system. In addition, the simulation system is able to incorporate advanced methods for monitoring, controlling, tracking, and modeling behavior. The simulation model of the local distribution grid can be executed with the smart control of charging and discharging powers of the EVs according to the load situation in the local distribution grid. The resulting simulation system can be applied to the study of balancing local smart grids with EV

  10. Intelligent Resource Management for Local Area Networks: Approach and Evolution

    Science.gov (United States)

    Meike, Roger

    1988-01-01

    The Data Management System network is a complex and important part of manned space platforms. Its efficient operation is vital to crew, subsystems and experiments. AI is being considered to aid in the initial design of the network and to augment the management of its operation. The Intelligent Resource Management for Local Area Networks (IRMA-LAN) project is concerned with the application of AI techniques to network configuration and management. A network simulation was constructed employing real time process scheduling for realistic loads, and utilizing the IEEE 802.4 token passing scheme. This simulation is an integral part of the construction of the IRMA-LAN system. From it, a causal model is being constructed for use in prediction and deep reasoning about the system configuration. An AI network design advisor is being added to help in the design of an efficient network. The AI portion of the system is planned to evolve into a dynamic network management aid. The approach, the integrated simulation, project evolution, and some initial results are described.

  11. A novel approach for SEMG signal classification with adaptive local binary patterns.

    Science.gov (United States)

    Ertuğrul, Ömer Faruk; Kaya, Yılmaz; Tekin, Ramazan

    2016-07-01

    Feature extraction plays a major role in the pattern recognition process, and this paper presents a novel feature extraction approach, adaptive local binary pattern (aLBP). aLBP is built on the local binary pattern (LBP), which is an image processing method, and one-dimensional local binary pattern (1D-LBP). In LBP, each pixel is compared with its neighbors. Similarly, in 1D-LBP, each data in the raw is judged against its neighbors. 1D-LBP extracts feature based on local changes in the signal. Therefore, it has high a potential to be employed in medical purposes. Since, each action or abnormality, which is recorded in SEMG signals, has its own pattern, and via the 1D-LBP these (hidden) patterns may be detected. But, the positions of the neighbors in 1D-LBP are constant depending on the position of the data in the raw. Also, both LBP and 1D-LBP are very sensitive to noise. Therefore, its capacity in detecting hidden patterns is limited. To overcome these drawbacks, aLBP was proposed. In aLBP, the positions of the neighbors and their values can be assigned adaptively via the down-sampling and the smoothing coefficients. Therefore, the potential to detect (hidden) patterns, which may express an illness or an action, is really increased. To validate the proposed feature extraction approach, two different datasets were employed. Achieved accuracies by the proposed approach were higher than obtained results by employed popular feature extraction approaches and the reported results in the literature. Obtained accuracy results were brought out that the proposed method can be employed to investigate SEMG signals. In summary, this work attempts to develop an adaptive feature extraction scheme that can be utilized for extracting features from local changes in different categories of time-varying signals.

  12. A method for improved clustering and classification of microscopy images using quantitative co-localization coefficients

    LENUS (Irish Health Repository)

    Singan, Vasanth R

    2012-06-08

    AbstractBackgroundThe localization of proteins to specific subcellular structures in eukaryotic cells provides important information with respect to their function. Fluorescence microscopy approaches to determine localization distribution have proved to be an essential tool in the characterization of unknown proteins, and are now particularly pertinent as a result of the wide availability of fluorescently-tagged constructs and antibodies. However, there are currently very few image analysis options able to effectively discriminate proteins with apparently similar distributions in cells, despite this information being important for protein characterization.FindingsWe have developed a novel method for combining two existing image analysis approaches, which results in highly efficient and accurate discrimination of proteins with seemingly similar distributions. We have combined image texture-based analysis with quantitative co-localization coefficients, a method that has traditionally only been used to study the spatial overlap between two populations of molecules. Here we describe and present a novel application for quantitative co-localization, as applied to the study of Rab family small GTP binding proteins localizing to the endomembrane system of cultured cells.ConclusionsWe show how quantitative co-localization can be used alongside texture feature analysis, resulting in improved clustering of microscopy images. The use of co-localization as an additional clustering parameter is non-biased and highly applicable to high-throughput image data sets.

  13. A Bayesian network approach for modeling local failure in lung cancer

    International Nuclear Information System (INIS)

    Oh, Jung Hun; Craft, Jeffrey; Al Lozi, Rawan; Vaidya, Manushka; Meng, Yifan; Deasy, Joseph O; Bradley, Jeffrey D; El Naqa, Issam

    2011-01-01

    Locally advanced non-small cell lung cancer (NSCLC) patients suffer from a high local failure rate following radiotherapy. Despite many efforts to develop new dose-volume models for early detection of tumor local failure, there was no reported significant improvement in their application prospectively. Based on recent studies of biomarker proteins' role in hypoxia and inflammation in predicting tumor response to radiotherapy, we hypothesize that combining physical and biological factors with a suitable framework could improve the overall prediction. To test this hypothesis, we propose a graphical Bayesian network framework for predicting local failure in lung cancer. The proposed approach was tested using two different datasets of locally advanced NSCLC patients treated with radiotherapy. The first dataset was collected retrospectively, which comprises clinical and dosimetric variables only. The second dataset was collected prospectively in which in addition to clinical and dosimetric information, blood was drawn from the patients at various time points to extract candidate biomarkers as well. Our preliminary results show that the proposed method can be used as an efficient method to develop predictive models of local failure in these patients and to interpret relationships among the different variables in the models. We also demonstrate the potential use of heterogeneous physical and biological variables to improve the model prediction. With the first dataset, we achieved better performance compared with competing Bayesian-based classifiers. With the second dataset, the combined model had a slightly higher performance compared to individual physical and biological models, with the biological variables making the largest contribution. Our preliminary results highlight the potential of the proposed integrated approach for predicting post-radiotherapy local failure in NSCLC patients.

  14. Comparison and combination of "direct" and fragment based local correlation methods: Cluster in molecules and domain based local pair natural orbital perturbation and coupled cluster theories

    Science.gov (United States)

    Guo, Yang; Becker, Ute; Neese, Frank

    2018-03-01

    Local correlation theories have been developed in two main flavors: (1) "direct" local correlation methods apply local approximation to the canonical equations and (2) fragment based methods reconstruct the correlation energy from a series of smaller calculations on subsystems. The present work serves two purposes. First, we investigate the relative efficiencies of the two approaches using the domain-based local pair natural orbital (DLPNO) approach as the "direct" method and the cluster in molecule (CIM) approach as the fragment based approach. Both approaches are applied in conjunction with second-order many-body perturbation theory (MP2) as well as coupled-cluster theory with single-, double- and perturbative triple excitations [CCSD(T)]. Second, we have investigated the possible merits of combining the two approaches by performing CIM calculations with DLPNO methods serving as the method of choice for performing the subsystem calculations. Our cluster-in-molecule approach is closely related to but slightly deviates from approaches in the literature since we have avoided real space cutoffs. Moreover, the neglected distant pair correlations in the previous CIM approach are considered approximately. Six very large molecules (503-2380 atoms) were studied. At both MP2 and CCSD(T) levels of theory, the CIM and DLPNO methods show similar efficiency. However, DLPNO methods are more accurate for 3-dimensional systems. While we have found only little incentive for the combination of CIM with DLPNO-MP2, the situation is different for CIM-DLPNO-CCSD(T). This combination is attractive because (1) the better parallelization opportunities offered by CIM; (2) the methodology is less memory intensive than the genuine DLPNO-CCSD(T) method and, hence, allows for large calculations on more modest hardware; and (3) the methodology is applicable and efficient in the frequently met cases, where the largest subsystem calculation is too large for the canonical CCSD(T) method.

  15. Rescaled Local Interaction Simulation Approach for Shear Wave Propagation Modelling in Magnetic Resonance Elastography

    Directory of Open Access Journals (Sweden)

    Z. Hashemiyan

    2016-01-01

    Full Text Available Properties of soft biological tissues are increasingly used in medical diagnosis to detect various abnormalities, for example, in liver fibrosis or breast tumors. It is well known that mechanical stiffness of human organs can be obtained from organ responses to shear stress waves through Magnetic Resonance Elastography. The Local Interaction Simulation Approach is proposed for effective modelling of shear wave propagation in soft tissues. The results are validated using experimental data from Magnetic Resonance Elastography. These results show the potential of the method for shear wave propagation modelling in soft tissues. The major advantage of the proposed approach is a significant reduction of computational effort.

  16. Rescaled Local Interaction Simulation Approach for Shear Wave Propagation Modelling in Magnetic Resonance Elastography

    Science.gov (United States)

    Packo, P.; Staszewski, W. J.; Uhl, T.

    2016-01-01

    Properties of soft biological tissues are increasingly used in medical diagnosis to detect various abnormalities, for example, in liver fibrosis or breast tumors. It is well known that mechanical stiffness of human organs can be obtained from organ responses to shear stress waves through Magnetic Resonance Elastography. The Local Interaction Simulation Approach is proposed for effective modelling of shear wave propagation in soft tissues. The results are validated using experimental data from Magnetic Resonance Elastography. These results show the potential of the method for shear wave propagation modelling in soft tissues. The major advantage of the proposed approach is a significant reduction of computational effort. PMID:26884808

  17. A local level set method based on a finite element method for unstructured meshes

    International Nuclear Information System (INIS)

    Ngo, Long Cu; Choi, Hyoung Gwon

    2016-01-01

    A local level set method for unstructured meshes has been implemented by using a finite element method. A least-square weighted residual method was employed for implicit discretization to solve the level set advection equation. By contrast, a direct re-initialization method, which is directly applicable to the local level set method for unstructured meshes, was adopted to re-correct the level set function to become a signed distance function after advection. The proposed algorithm was constructed such that the advection and direct reinitialization steps were conducted only for nodes inside the narrow band around the interface. Therefore, in the advection step, the Gauss–Seidel method was used to update the level set function using a node-by-node solution method. Some benchmark problems were solved by using the present local level set method. Numerical results have shown that the proposed algorithm is accurate and efficient in terms of computational time

  18. A local level set method based on a finite element method for unstructured meshes

    Energy Technology Data Exchange (ETDEWEB)

    Ngo, Long Cu; Choi, Hyoung Gwon [School of Mechanical Engineering, Seoul National University of Science and Technology, Seoul (Korea, Republic of)

    2016-12-15

    A local level set method for unstructured meshes has been implemented by using a finite element method. A least-square weighted residual method was employed for implicit discretization to solve the level set advection equation. By contrast, a direct re-initialization method, which is directly applicable to the local level set method for unstructured meshes, was adopted to re-correct the level set function to become a signed distance function after advection. The proposed algorithm was constructed such that the advection and direct reinitialization steps were conducted only for nodes inside the narrow band around the interface. Therefore, in the advection step, the Gauss–Seidel method was used to update the level set function using a node-by-node solution method. Some benchmark problems were solved by using the present local level set method. Numerical results have shown that the proposed algorithm is accurate and efficient in terms of computational time.

  19. Local Gaussian approximation in the generator coordinate method

    International Nuclear Information System (INIS)

    Onishi, Naoki; Une, Tsutomu.

    1975-01-01

    A transformation from a non-orthogonal representation to an orthogonal representation of wave functions is studied in the generator coordinate method. A differential equation can be obtained by the transformation for a case that the eigenvalue equation of the overlap kernel is solvable. By assuming local Gaussian overlap, we derive a Schroedinger-type equation for the collective motion from the Hill-Wheeler integral equation. (auth.)

  20. Local Gaussian approximation in the generator coordinate method

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, N [Tokyo Univ. (Japan). Coll. of General Education; Une, Tsutomu

    1975-02-01

    A transformation from a non-orthogonal representation to an orthogonal representation of wave functions is studied in the generator coordinate method. A differential equation can be obtained by the transformation for a case that the eigenvalue equation of the overlap kernel is solvable. By assuming local Gaussian overlap, we derive a Schroedinger-type equation for the collective motion from the Hill-Wheeler integral equation.

  1. A unified approach to global and local beam position feedback

    International Nuclear Information System (INIS)

    Chung, Y.

    1994-01-01

    The Advanced Photon Source (APS) will implement both global and local beam position feedback systems to stabilize the particle and X-ray beams for the storage ring. The global feedback system uses 40 BPMs and 40 correctors per plane. Singular value decomposition (SVD) of the response matrix is used for closed orbit correction. The local feedback system uses two X-ray BPMS, two rf BPMS, and the four-magnet local bump to control the angle and displacement of the X-ray beam from a bending magnet or an insertion device. Both the global and local feedback systems are based on digital signal processing (DSP) running at 4-kHz sampling rate with a proportional, integral, and derivative (PID) control algorithm. In this paper, we will discuss resolution of the conflict among multiple local feedback systems due to local bump closure error and decoupling of the global and local feedback systems to maximize correction efficiency. In this scheme, the global feedback system absorbs the local bump closure error and the local feedback systems compensate for the effect of global feedback on the local beamlines. The required data sharing between the global and local feedback systems is done through the fiber-optically networked reflective memory

  2. Exploration of barriers and facilitators to publishing local public health findings: A mixed methods protocol

    OpenAIRE

    Smith, Selina A.; Webb, Nancy C.; Blumenthal, Daniel S.; Willcox, Bobbie; Ballance, Darra; Kinard, Faith; Gates, Madison L.

    2016-01-01

    Background Worldwide, the US accounts for a large proportion of journals related to public health. Although the American Public Health Association (APHA) includes 54 affiliated regional and state associations, little is known about their capacity to support public health scholarship. The aim of this study is to assess barriers and facilitators to operation of state journals for the dissemination of local public health research and practices. Methods A mixed methods approach will be used to co...

  3. Localization of canine brachycephaly using an across breed mapping approach.

    Directory of Open Access Journals (Sweden)

    Danika Bannasch

    2010-03-01

    Full Text Available The domestic dog, Canis familiaris, exhibits profound phenotypic diversity and is an ideal model organism for the genetic dissection of simple and complex traits. However, some of the most interesting phenotypes are fixed in particular breeds and are therefore less tractable to genetic analysis using classical segregation-based mapping approaches. We implemented an across breed mapping approach using a moderately dense SNP array, a low number of animals and breeds carefully selected for the phenotypes of interest to identify genetic variants responsible for breed-defining characteristics. Using a modest number of affected (10-30 and control (20-60 samples from multiple breeds, the correct chromosomal assignment was identified in a proof of concept experiment using three previously defined loci; hyperuricosuria, white spotting and chondrodysplasia. Genome-wide association was performed in a similar manner for one of the most striking morphological traits in dogs: brachycephalic head type. Although candidate gene approaches based on comparable phenotypes in mice and humans have been utilized for this trait, the causative gene has remained elusive using this method. Samples from nine affected breeds and thirteen control breeds identified strong genome-wide associations for brachycephalic head type on Cfa 1. Two independent datasets identified the same genomic region. Levels of relative heterozygosity in the associated region indicate that it has been subjected to a selective sweep, consistent with it being a breed defining morphological characteristic. Genotyping additional dogs in the region confirmed the association. To date, the genetic structure of dog breeds has primarily been exploited for genome wide association for segregating traits. These results demonstrate that non-segregating traits under strong selection are equally tractable to genetic analysis using small sample numbers.

  4. Meshfree Local Radial Basis Function Collocation Method with Image Nodes

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Seung Ki; Kim, Minjae [Pukyong National University, Busan (Korea, Republic of)

    2017-07-15

    We numerically solve two-dimensional heat diffusion problems by using a simple variant of the meshfree local radial-basis function (RBF) collocation method. The main idea is to include an additional set of sample nodes outside the problem domain, similarly to the method of images in electrostatics, to perform collocation on the domain boundaries. We can thereby take into account the temperature profile as well as its gradients specified by boundary conditions at the same time, which holds true even for a node where two or more boundaries meet with different boundary conditions. We argue that the image method is computationally efficient when combined with the local RBF collocation method, whereas the addition of image nodes becomes very costly in case of the global collocation. We apply our modified method to a benchmark test of a boundary value problem, and find that this simple modification reduces the maximum error from the analytic solution significantly. The reduction is small for an initial value problem with simpler boundary conditions. We observe increased numerical instability, which has to be compensated for by a sufficient number of sample nodes and/or more careful parameter choices for time integration.

  5. Biopsy Needle Localization and Tracking Using ROI-RK Method

    Directory of Open Access Journals (Sweden)

    Yue Zhao

    2014-01-01

    Full Text Available ROI-RK method is a biopsy needle localization and tracking method. Previous research work has proved that it has a robust performance on different series of simulated 3D US volumes. Unfortunately, in real situations, because of the strong speckle noise of the ultrasound image and the different echogenic properties of the tissues, the real 3D US volumes have more complex background than the simulated images used previously. In this paper, to adapt the ROI-RK method in real 3D US volumes, a line-filter enhancement calculation only in the ROI is added to increase the contrast between the needle and background tissue, decreasing the phenomenon of expansion of the biopsy needle due to reverberation of ultrasound in the needle. To make the ROI-RK method more stable, a self-correction system is also implemented. Real data have been acquired on an ex vivo heart of lamb. The result of the ROI-RK method shows that it is capable to localize and track the biopsy needle in real situations, and it satisfies the demand of real-time application.

  6. Local to global: a collaborative approach to volcanic risk assessment

    Science.gov (United States)

    Calder, Eliza; Loughlin, Sue; Barsotti, Sara; Bonadonna, Costanza; Jenkins, Susanna

    2017-04-01

    -economic conditions tending to influence longer term well-being and recovery. The volcanological community includes almost 100 Volcano Observatories worldwide, the official institutions responsible for monitoring volcanoes. They may be dedicated institutions, or operate from national institutions (geological surveys, universities, met agencies). They have a key role in early warning, forecasting and long term hazard assessment (often in the form of volcanic hazards maps). The complexity of volcanic systems means that once unrest begins there are multiple potential eruptive outcomes and short term forecasts can change rapidly. This local knowledge of individual volcanoes underpins hazard and risk assessments developed at national, regional and global scales. Combining this local expertise with the knowledge of the international research community (including interdisciplinary perspectives) creates a powerful partnership. A collaborative approach is therefore needed to develop effective volcanic risk assessments at regional to global scale. The World Organisation of Volcano Observatories is a Commission of IAVCEI, alongside other Commissions such as 'Hazard and Risk' (with an active working group on volcanic hazards maps) and the 'Cities and Volcanoes' Commission. The Global Volcano Model network is a collaborative initiative developing hazards and risk information at national to global scales, underpinned by local expertise. Partners include IAVCEI, Smithsonian Institution, International Volcanic Health Hazard Network, VHub and other initiatives and institutions.

  7. Extension of local front reconstruction method with controlled coalescence model

    Science.gov (United States)

    Rajkotwala, A. H.; Mirsandi, H.; Peters, E. A. J. F.; Baltussen, M. W.; van der Geld, C. W. M.; Kuerten, J. G. M.; Kuipers, J. A. M.

    2018-02-01

    The physics of droplet collisions involves a wide range of length scales. This poses a challenge to accurately simulate such flows with standard fixed grid methods due to their inability to resolve all relevant scales with an affordable number of computational grid cells. A solution is to couple a fixed grid method with subgrid models that account for microscale effects. In this paper, we improved and extended the Local Front Reconstruction Method (LFRM) with a film drainage model of Zang and Law [Phys. Fluids 23, 042102 (2011)]. The new framework is first validated by (near) head-on collision of two equal tetradecane droplets using experimental film drainage times. When the experimental film drainage times are used, the LFRM method is better in predicting the droplet collisions, especially at high velocity in comparison with other fixed grid methods (i.e., the front tracking method and the coupled level set and volume of fluid method). When the film drainage model is invoked, the method shows a good qualitative match with experiments, but a quantitative correspondence of the predicted film drainage time with the experimental drainage time is not obtained indicating that further development of film drainage model is required. However, it can be safely concluded that the LFRM coupled with film drainage models is much better in predicting the collision dynamics than the traditional methods.

  8. A strategic approach to workforce development for local public health.

    Science.gov (United States)

    Bryant, Beverley; Ward, Megan

    2017-11-09

    In 2009, Peel Public Health set a vision to transform the work of public health from efficient delivery of public health services as defined by provincial mandate to the robust analysis of the health status of the local population and selection and implementation of programming to achieve best health outcomes. A strategic approach to the workforce was a key enabler. PPH is a public health unit in Ontario that serves 1.4 million people. An organization-wide strategic workforce development program was instituted. It is theory-based, evidence-informed and data-driven. A first step was a conceptual framework, followed by interventions in workforce planning, human resources management, and capacity development. The program was built on evidence reviews, theory, and public health core competencies. Interventions spread across the employee work-life span. Capacity development based on the public health core competencies is a main focus, particularly analytical capacity to support decision-making. Employees gain skill and knowledge in comprehensive population health. Leadership evolves as work shifts to the analysis of health status and development of interventions. Effective human resource processes ensure appropriate job design, recruitment and orientation. Analysis of the workforce leads to vigorous employee development to ensure a strong pool of potential leadership successors. Theory, research evidence, and data provide a robust foundation for workforce development. Competencies are important inputs to job descriptions, recruitment, training, and human resource processes. A comprehensive workforce development strategy enables the development of a skilled workforce capable of responding to the needs of the population it serves.

  9. The modal surface interpolation method for damage localization

    Science.gov (United States)

    Pina Limongelli, Maria

    2017-05-01

    The Interpolation Method (IM) has been previously proposed and successfully applied for damage localization in plate like structures. The method is based on the detection of localized reductions of smoothness in the Operational Deformed Shapes (ODSs) of the structure. The IM can be applied to any type of structure provided the ODSs are estimated accurately in the original and in the damaged configurations. If the latter circumstance fails to occur, for example when the structure is subjected to an unknown input(s) or if the structural responses are strongly corrupted by noise, both false and missing alarms occur when the IM is applied to localize a concentrated damage. In order to overcome these drawbacks a modification of the method is herein investigated. An ODS is the deformed shape of a structure subjected to a harmonic excitation: at resonances the ODS are dominated by the relevant mode shapes. The effect of noise at resonance is usually lower with respect to other frequency values hence the relevant ODS are estimated with higher reliability. Several methods have been proposed to reliably estimate modal shapes in case of unknown input. These two circumstances can be exploited to improve the reliability of the IM. In order to reduce or eliminate the drawbacks related to the estimation of the ODSs in case of noisy signals, in this paper is investigated a modified version of the method based on a damage feature calculated considering the interpolation error relevant only to the modal shapes and not to all the operational shapes in the significant frequency range. Herein will be reported the comparison between the results of the IM in its actual version (with the interpolation error calculated summing up the contributions of all the operational shapes) and in the new proposed version (with the estimation of the interpolation error limited to the modal shapes).

  10. Multiple instance learning tracking method with local sparse representation

    KAUST Repository

    Xie, Chengjun

    2013-10-01

    When objects undergo large pose change, illumination variation or partial occlusion, most existed visual tracking algorithms tend to drift away from targets and even fail in tracking them. To address this issue, in this study, the authors propose an online algorithm by combining multiple instance learning (MIL) and local sparse representation for tracking an object in a video system. The key idea in our method is to model the appearance of an object by local sparse codes that can be formed as training data for the MIL framework. First, local image patches of a target object are represented as sparse codes with an overcomplete dictionary, where the adaptive representation can be helpful in overcoming partial occlusion in object tracking. Then MIL learns the sparse codes by a classifier to discriminate the target from the background. Finally, results from the trained classifier are input into a particle filter framework to sequentially estimate the target state over time in visual tracking. In addition, to decrease the visual drift because of the accumulative errors when updating the dictionary and classifier, a two-step object tracking method combining a static MIL classifier with a dynamical MIL classifier is proposed. Experiments on some publicly available benchmarks of video sequences show that our proposed tracker is more robust and effective than others. © The Institution of Engineering and Technology 2013.

  11. Real-space local polynomial basis for solid-state electronic-structure calculations: A finite-element approach

    International Nuclear Information System (INIS)

    Pask, J.E.; Klein, B.M.; Fong, C.Y.; Sterne, P.A.

    1999-01-01

    We present an approach to solid-state electronic-structure calculations based on the finite-element method. In this method, the basis functions are strictly local, piecewise polynomials. Because the basis is composed of polynomials, the method is completely general and its convergence can be controlled systematically. Because the basis functions are strictly local in real space, the method allows for variable resolution in real space; produces sparse, structured matrices, enabling the effective use of iterative solution methods; and is well suited to parallel implementation. The method thus combines the significant advantages of both real-space-grid and basis-oriented approaches and so promises to be particularly well suited for large, accurate ab initio calculations. We develop the theory of our approach in detail, discuss advantages and disadvantages, and report initial results, including electronic band structures and details of the convergence of the method. copyright 1999 The American Physical Society

  12. Machine-learning approach for local classification of crystalline structures in multiphase systems

    Science.gov (United States)

    Dietz, C.; Kretz, T.; Thoma, M. H.

    2017-07-01

    Machine learning is one of the most popular fields in computer science and has a vast number of applications. In this work we will propose a method that will use a neural network to locally identify crystal structures in a mixed phase Yukawa system consisting of fcc, hcp, and bcc clusters and disordered particles similar to plasma crystals. We compare our approach to already used methods and show that the quality of identification increases significantly. The technique works very well for highly disturbed lattices and shows a flexible and robust way to classify crystalline structures that can be used by only providing particle positions. This leads to insights into highly disturbed crystalline structures.

  13. The Conceptual Approaches to Strategic Management of Region Using the Spatially Localized Agrarian Economic Systems

    Directory of Open Access Journals (Sweden)

    Petrenko Natalia О.

    2017-10-01

    Full Text Available The article is aimed at improving the theoretical and methodical provisions of the cluster approach to development of the spatially localized systems of the agricultural sector of Ukrainian economy at the regional level. Based on generalizing the relevant theoretical provisions, the identified characteristics of formation and development of the spatially localized systems, it has been found that, originating in the form of economic growth zones, they have been transformed into clustered and subclustered forms. It has been indicated that a prospective form of further development of the spatially localized systems is formation of subclustered structures that take account of the established specialization of localities, appropriate infrastructure, resource availability. The possibility of creating a project of developing a cluster formation was discussed on the example of the Central Economic Area. A complex of basic requirements for the intended localization of the cluster has been formulated. Proceeding from the results of the study, practical proposals for strategic management of region have been developed on the basis of development of cluster formations, using the spatially localized agrarian economic systems.

  14. Field theoretic approach to dynamical orbital localization in ab initio molecular dynamics

    International Nuclear Information System (INIS)

    Thomas, Jordan W.; Iftimie, Radu; Tuckerman, Mark E.

    2004-01-01

    Techniques from gauge-field theory are employed to derive an alternative formulation of the Car-Parrinello ab initio molecular-dynamics method that allows maximally localized Wannier orbitals to be generated dynamically as the calculation proceeds. In particular, the Car-Parrinello Lagrangian is mapped onto an SU(n) non-Abelian gauge-field theory and the fictitious kinetic energy in the Car-Parrinello Lagrangian is modified to yield a fully gauge-invariant form. The Dirac gauge-fixing method is then employed to derive a set of equations of motion that automatically maintain orbital locality by restricting the orbitals to remain in the 'Wannier gauge'. An approximate algorithm for integrating the equations of motion that is stable and maintains orbital locality is then developed based on the exact equations of motion. It is shown in a realistic application (64 water molecules plus one hydrogen-chloride molecule in a periodic box) that orbital locality can be maintained with only a modest increase in CPU time. The ability to keep orbitals localized in an ab initio molecular-dynamics calculation is a crucial ingredient in the development of emerging linear scaling approaches

  15. A domain decomposition approach for full-field measurements based identification of local elastic parameters

    KAUST Repository

    Lubineau, Gilles

    2015-03-01

    We propose a domain decomposition formalism specifically designed for the identification of local elastic parameters based on full-field measurements. This technique is made possible by a multi-scale implementation of the constitutive compatibility method. Contrary to classical approaches, the constitutive compatibility method resolves first some eigenmodes of the stress field over the structure rather than directly trying to recover the material properties. A two steps micro/macro reconstruction of the stress field is performed: a Dirichlet identification problem is solved first over every subdomain, the macroscopic equilibrium is then ensured between the subdomains in a second step. We apply the method to large linear elastic 2D identification problems to efficiently produce estimates of the material properties at a much lower computational cost than classical approaches.

  16. Teaching Local Lore in EFL Class: New Approaches

    Science.gov (United States)

    Yarmakeev, Iskander E.; Pimenova, Tatiana S.; Zamaletdinova, Gulyusa R.

    2016-01-01

    This paper is dedicated to the up-to-date educational problem, that is, the role of local lore in teaching EFL to University students. Although many educators admit that local lore knowledge plays a great role in the development of a well-bred and well-educated personality and meets students' needs, the problem has not been thoroughly studied.…

  17. An Odometry-free Approach for Simultaneous Localization and Online Hybrid Map Building

    Directory of Open Access Journals (Sweden)

    Wei Hong Chin

    2016-11-01

    Full Text Available In this paper, a new approach is proposed for mobile robot localization and hybrid map building simultaneously without using any odometry hardware system. The proposed method termed as Genetic Bayesian ARAM which comprises two main components: 1 Steady state genetic algorithm (SSGA for self-localization and occupancy grid map building; 2 Bayesian Adaptive Resonance Associative Memory (ARAM for online topological map building. The model of the explored environment is formed as a hybrid representation, both topological and grid-based, and it is incrementally constructed during the exploration process. During occupancy map building, robot estimated self-position is updated by SSGA. At the same time, robot estimated self position is transmit to Bayesian ARAM for topological map building and localization. The effectiveness of our proposed approach is validated by a number of standardized benchmark datasets and real experimental results carried on mobile robot. Benchmark datasets are used to verify the proposed method capable of generating topological map in different environment conditions. Real robot experiment is to verify the proposed method can be implemented in real world.

  18. Local regression type methods applied to the study of geophysics and high frequency financial data

    Science.gov (United States)

    Mariani, M. C.; Basu, K.

    2014-09-01

    In this work we applied locally weighted scatterplot smoothing techniques (Lowess/Loess) to Geophysical and high frequency financial data. We first analyze and apply this technique to the California earthquake geological data. A spatial analysis was performed to show that the estimation of the earthquake magnitude at a fixed location is very accurate up to the relative error of 0.01%. We also applied the same method to a high frequency data set arising in the financial sector and obtained similar satisfactory results. The application of this approach to the two different data sets demonstrates that the overall method is accurate and efficient, and the Lowess approach is much more desirable than the Loess method. The previous works studied the time series analysis; in this paper our local regression models perform a spatial analysis for the geophysics data providing different information. For the high frequency data, our models estimate the curve of best fit where data are dependent on time.

  19. A Secure Localization Approach against Wormhole Attacks Using Distance Consistency

    Directory of Open Access Journals (Sweden)

    Lou Wei

    2010-01-01

    Full Text Available Wormhole attacks can negatively affect the localization in wireless sensor networks. A typical wormhole attack can be launched by two colluding attackers, one of which sniffs packets at one point in the network and tunnels them through a wired or wireless link to another point, and the other relays them within its vicinity. In this paper, we investigate the impact of the wormhole attack on the localization and propose a novel distance-consistency-based secure localization scheme against wormhole attacks, which includes three phases of wormhole attack detection, valid locators identification and self-localization. The theoretical model is further formulated to analyze the proposed secure localization scheme. The simulation results validate the theoretical results and also demonstrate the effectiveness of our proposed scheme.

  20. A local adaptive method for the numerical approximation in seismic wave modelling

    Directory of Open Access Journals (Sweden)

    Galuzzi Bruno G.

    2017-12-01

    Full Text Available We propose a new numerical approach for the solution of the 2D acoustic wave equation to model the predicted data in the field of active-source seismic inverse problems. This method consists in using an explicit finite difference technique with an adaptive order of approximation of the spatial derivatives that takes into account the local velocity at the grid nodes. Testing our method to simulate the recorded seismograms in a marine seismic acquisition, we found that the low computational time and the low approximation error of the proposed approach make it suitable in the context of seismic inversion problems.

  1. Local Field Response Method Phenomenologically Introducing Spin Correlations

    Science.gov (United States)

    Tomaru, Tatsuya

    2018-03-01

    The local field response (LFR) method is a way of searching for the ground state in a similar manner to quantum annealing. However, the LFR method operates on a classical machine, and quantum effects are introduced through a priori information and through phenomenological means reflecting the states during the computations. The LFR method has been treated with a one-body approximation, and therefore, the effect of entanglement has not been sufficiently taken into account. In this report, spin correlations are phenomenologically introduced as one of the effects of entanglement, by which multiple tunneling at anticrossing points is taken into account. As a result, the accuracy of solutions for a 128-bit system increases by 31% compared with that without spin correlations.

  2. Impact localization on composite structures using time difference and MUSIC approach

    Science.gov (United States)

    Zhong, Yongteng; Xiang, Jiawei

    2017-05-01

    1-D uniform linear array (ULA) has the shortcoming of the half-plane mirror effect, which does not allow discriminating between a target placed above the array and a target placed below the array. This paper presents time difference (TD) and multiple signal classification (MUSIC) based omni-directional impact localization on a large stiffened composite structure using improved linear array, which is able to perform omni-directional 360° localization. This array contains 2M+3 PZT sensors, where 2M+1 PZT sensors are arranged as a uniform linear array, and the other two PZT sensors are placed above and below the array. Firstly, the arrival times of impact signals observed by the other two sensors are determined using the wavelet transform. Compared with each other, the direction range of impact source can be decided in general, 0°to 180° or 180°to 360°. And then, two dimensional multiple signal classification (2D-MUSIC) based spatial spectrum formula using the uniform linear array is applied for impact localization by the general direction range. When the arrival times of impact signals observed by upper PZT is equal to that of lower PZT, the direction can be located in x axis (0°or 180°). And time difference based MUSIC method is present to locate impact position. To verify the proposed approach, the proposed approach is applied to a composite structure. The localization results are in good agreement with the actual impact occurring positions.

  3. LMFBR subassembly response to local pressure loadings: an experimental approach

    International Nuclear Information System (INIS)

    Marciniak, T.J.; Ash, J.E.; Marchertas, A.H.; Cagliostro, D.J.

    1975-01-01

    An experimental program to determine the response of LMFBR-type subassemblies to local subassembly accidents caused by pressure loadings is described. Some results are presented and compared with computer calculations

  4. The Comparative Study Of Local Governance: Towards A Global Approach The Comparative Study Of Local Governance: Towards A Global Approach

    Directory of Open Access Journals (Sweden)

    Gerry Stoker

    2010-12-01

    Full Text Available The comparative study of local governance has been too focused on the institutional arrangements of the Systems of different nation states rather than the more fundamental issue of the societal functions performed by local government. This article focuses attention on four societal roles that local government systems undertake. They can support political identity, underwrite economic development, facilitate social welfare provision or act as a lifestyle co-ordinator through the practice of community governance. Linking our investigation to the embedded societal roles of local government in different systems opens up the opportunity for a more genuinely global comparative perspective. It also helps us to understand the likely forms of politics associated with different systems of local governance. It also enables us to explore the sustainability of different systems of local governance. It is suggested that a strong system of local government is likely to be one that is able to combine societal roles to a substantial degree. A vulnerable local government system is one trapped with one function that in changing societal and economic circumstances could find itself under threat.El estudio comparado de la gobernanza local se ha focalizado excesivamente en los arreglos institucionales de los sistemas de los diferentes Estados-nación en lugar de centrarse en el tema esencial de las funciones sociales que desempeñan los gobiernos locales. Este artículo centra su atención en cuatro roles sociales que desempeñan los sistemas de gobierno local. Pueden proporcionar identidad política, garantizar el desarrollo económico, facilitar la provisión de servicios sociales o actuar como coordinador de la forma de vida mediante la práctica de la gobernanza comunitaria. La vinculación de la investigación a los roles sociales asumidos por los gobiernos locales en los diferentes sistemas proporciona la posibilidad de adoptar una perspectiva global comparada

  5. Evaluating the sensitization potential of surfactants: integrating data from the local lymph node assay, guinea pig maximization test, and in vitro methods in a weight-of-evidence approach.

    Science.gov (United States)

    Ball, Nicholas; Cagen, Stuart; Carrillo, Juan-Carlos; Certa, Hans; Eigler, Dorothea; Emter, Roger; Faulhammer, Frank; Garcia, Christine; Graham, Cynthia; Haux, Carl; Kolle, Susanne N; Kreiling, Reinhard; Natsch, Andreas; Mehling, Annette

    2011-08-01

    An integral part of hazard and safety assessments is the estimation of a chemical's potential to cause skin sensitization. Currently, only animal tests (OECD 406 and 429) are accepted in a regulatory context. Nonanimal test methods are being developed and formally validated. In order to gain more insight into the responses induced by eight exemplary surfactants, a battery of in vivo and in vitro tests were conducted using the same batch of chemicals. In general, the surfactants were negative in the GPMT, KeratinoSens and hCLAT assays and none formed covalent adducts with test peptides. In contrast, all but one was positive in the LLNA. Most were rated as being irritants by the EpiSkin assay with the additional endpoint, IL1-alpha. The weight of evidence based on this comprehensive testing indicates that, with one exception, they are non-sensitizing skin irritants, confirming that the LLNA tends to overestimate the sensitization potential of surfactants. As results obtained from LLNAs are considered as the gold standard for the development of new nonanimal alternative test methods, results such as these highlight the necessity to carefully evaluate the applicability domains of test methods in order to develop reliable nonanimal alternative testing strategies for sensitization testing. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. A Robust Vehicle Localization Approach Based on GNSS/IMU/DMI/LiDAR Sensor Fusion for Autonomous Vehicles.

    Science.gov (United States)

    Meng, Xiaoli; Wang, Heng; Liu, Bingbing

    2017-09-18

    Precise and robust localization in a large-scale outdoor environment is essential for an autonomous vehicle. In order to improve the performance of the fusion of GNSS (Global Navigation Satellite System)/IMU (Inertial Measurement Unit)/DMI (Distance-Measuring Instruments), a multi-constraint fault detection approach is proposed to smooth the vehicle locations in spite of GNSS jumps. Furthermore, the lateral localization error is compensated by the point cloud-based lateral localization method proposed in this paper. Experiment results have verified the algorithms proposed in this paper, which shows that the algorithms proposed in this paper are capable of providing precise and robust vehicle localization.

  7. A Robust Vehicle Localization Approach Based on GNSS/IMU/DMI/LiDAR Sensor Fusion for Autonomous Vehicles

    Directory of Open Access Journals (Sweden)

    Xiaoli Meng

    2017-09-01

    Full Text Available Precise and robust localization in a large-scale outdoor environment is essential for an autonomous vehicle. In order to improve the performance of the fusion of GNSS (Global Navigation Satellite System/IMU (Inertial Measurement Unit/DMI (Distance-Measuring Instruments, a multi-constraint fault detection approach is proposed to smooth the vehicle locations in spite of GNSS jumps. Furthermore, the lateral localization error is compensated by the point cloud-based lateral localization method proposed in this paper. Experiment results have verified the algorithms proposed in this paper, which shows that the algorithms proposed in this paper are capable of providing precise and robust vehicle localization.

  8. Mobile Ground-Based Radar Sensor for Localization and Mapping: An Evaluation of two Approaches

    Directory of Open Access Journals (Sweden)

    Damien Vivet

    2013-08-01

    Full Text Available This paper is concerned with robotic applications using a ground-based radar sensor for simultaneous localization and mapping problems. In mobile robotics, radar technology is interesting because of its long range and the robustness of radar waves to atmospheric conditions, making these sensors well-suited for extended outdoor robotic applications. Two localization and mapping approaches using data obtained from a 360° field of view microwave radar sensor are presented and compared. The first method is a trajectory-oriented simultaneous localization and mapping technique, which makes no landmark assumptions and avoids the data association problem. The estimation of the ego-motion makes use of the Fourier-Mellin transform for registering radar images in a sequence, from which the rotation and translation of the sensor motion can be estimated. The second approach uses the consequence of using a rotating range sensor in high speed robotics. In such a situation, movement combinations create distortions in the collected data. Velocimetry is achieved here by explicitly analysing these measurement distortions. As a result, the trajectory of the vehicle and then the radar map of outdoor environments can be obtained. The evaluation of experimental results obtained by the two methods is presented on real-world data from a vehicle moving at 30 km/h over a 2.5 km course.

  9. A New Method for Local Energy Planning in Developing Countries

    International Nuclear Information System (INIS)

    Van Beeck, N.

    2001-01-01

    Energy planning is an essential tool in the economic development of industrialized as well as developing countries. Energy planning in this paper is restricted to the selection of new energy systems for the production of proper energy forms in order to meet increased energy demand. This demand is actually the desire for certain energy services, which are the starting point of the new decision support method for local energy planning presented in this paper. In the decision making process concerning energy planning at the local level it is important to include context-related issues because the context determines for a large part the viability of the technologies or systems used. The context, in turn, is represented by the aims of the relevant actors, which are translated into measurable indicators to compare the different options. The impact assessment must allow for inclusion of all the indicators, either quantitative or qualitative in order to find the most appropriate technology for a region rather than the technically best or economically most optimal one. Appropriateness is defined by the context and is thus case specific, but the framework described in this paper is generally applicable within the given limitations. Note that the new method described in this paper is a decision support tool, implying that it does not decide for the energy planner which actions to take. The ultimate decision must be made by the planners themselves

  10. Feature Extraction Method for High Impedance Ground Fault Localization in Radial Power Distribution Networks

    DEFF Research Database (Denmark)

    Jensen, Kåre Jean; Munk, Steen M.; Sørensen, John Aasted

    1998-01-01

    A new approach to the localization of high impedance ground faults in compensated radial power distribution networks is presented. The total size of such networks is often very large and a major part of the monitoring of these is carried out manually. The increasing complexity of industrial...... of three phase voltages and currents. The method consists of a feature extractor, based on a grid description of the feeder by impulse responses, and a neural network for ground fault localization. The emphasis of this paper is the feature extractor, and the detection of the time instance of a ground fault...... processes and communication systems lead to demands for improved monitoring of power distribution networks so that the quality of power delivery can be kept at a controlled level. The ground fault localization method for each feeder in a network is based on the centralized frequency broadband measurement...

  11. The behaviour of the local error in splitting methods applied to stiff problems

    International Nuclear Information System (INIS)

    Kozlov, Roman; Kvaernoe, Anne; Owren, Brynjulf

    2004-01-01

    Splitting methods are frequently used in solving stiff differential equations and it is common to split the system of equations into a stiff and a nonstiff part. The classical theory for the local order of consistency is valid only for stepsizes which are smaller than what one would typically prefer to use in the integration. Error control and stepsize selection devices based on classical local order theory may lead to unstable error behaviour and inefficient stepsize sequences. Here, the behaviour of the local error in the Strang and Godunov splitting methods is explained by using two different tools, Lie series and singular perturbation theory. The two approaches provide an understanding of the phenomena from different points of view, but both are consistent with what is observed in numerical experiments

  12. The Robin Hood method - A novel numerical method for electrostatic problems based on a non-local charge transfer

    International Nuclear Information System (INIS)

    Lazic, Predrag; Stefancic, Hrvoje; Abraham, Hrvoje

    2006-01-01

    We introduce a novel numerical method, named the Robin Hood method, of solving electrostatic problems. The approach of the method is closest to the boundary element methods, although significant conceptual differences exist with respect to this class of methods. The method achieves equipotentiality of conducting surfaces by iterative non-local charge transfer. For each of the conducting surfaces, non-local charge transfers are performed between surface elements, which differ the most from the targeted equipotentiality of the surface. The method is tested against analytical solutions and its wide range of application is demonstrated. The method has appealing technical characteristics. For the problem with N surface elements, the computational complexity of the method essentially scales with N α , where α < 2, the required computer memory scales with N, while the error of the potential decreases exponentially with the number of iterations for many orders of magnitude of the error, without the presence of the Critical Slowing Down. The Robin Hood method could prove useful in other classical or even quantum problems. Some future development ideas for possible applications outside electrostatics are addressed

  13. Diffusion Monte Carlo approach versus adiabatic computation for local Hamiltonians

    Science.gov (United States)

    Bringewatt, Jacob; Dorland, William; Jordan, Stephen P.; Mink, Alan

    2018-02-01

    Most research regarding quantum adiabatic optimization has focused on stoquastic Hamiltonians, whose ground states can be expressed with only real non-negative amplitudes and thus for whom destructive interference is not manifest. This raises the question of whether classical Monte Carlo algorithms can efficiently simulate quantum adiabatic optimization with stoquastic Hamiltonians. Recent results have given counterexamples in which path-integral and diffusion Monte Carlo fail to do so. However, most adiabatic optimization algorithms, such as for solving MAX-k -SAT problems, use k -local Hamiltonians, whereas our previous counterexample for diffusion Monte Carlo involved n -body interactions. Here we present a 6-local counterexample which demonstrates that even for these local Hamiltonians there are cases where diffusion Monte Carlo cannot efficiently simulate quantum adiabatic optimization. Furthermore, we perform empirical testing of diffusion Monte Carlo on a standard well-studied class of permutation-symmetric tunneling problems and similarly find large advantages for quantum optimization over diffusion Monte Carlo.

  14. Local and Global Gestalt Laws: A Neurally Based Spectral Approach.

    Science.gov (United States)

    Favali, Marta; Citti, Giovanna; Sarti, Alessandro

    2017-02-01

    This letter presents a mathematical model of figure-ground articulation that takes into account both local and global gestalt laws and is compatible with the functional architecture of the primary visual cortex (V1). The local gestalt law of good continuation is described by means of suitable connectivity kernels that are derived from Lie group theory and quantitatively compared with long-range connectivity in V1. Global gestalt constraints are then introduced in terms of spectral analysis of a connectivity matrix derived from these kernels. This analysis performs grouping of local features and individuates perceptual units with the highest salience. Numerical simulations are performed, and results are obtained by applying the technique to a number of stimuli.

  15. An improved local radial point interpolation method for transient heat conduction analysis

    Science.gov (United States)

    Wang, Feng; Lin, Gao; Zheng, Bao-Jing; Hu, Zhi-Qiang

    2013-06-01

    The smoothing thin plate spline (STPS) interpolation using the penalty function method according to the optimization theory is presented to deal with transient heat conduction problems. The smooth conditions of the shape functions and derivatives can be satisfied so that the distortions hardly occur. Local weak forms are developed using the weighted residual method locally from the partial differential equations of the transient heat conduction. Here the Heaviside step function is used as the test function in each sub-domain to avoid the need for a domain integral. Essential boundary conditions can be implemented like the finite element method (FEM) as the shape functions possess the Kronecker delta property. The traditional two-point difference method is selected for the time discretization scheme. Three selected numerical examples are presented in this paper to demonstrate the availability and accuracy of the present approach comparing with the traditional thin plate spline (TPS) radial basis functions.

  16. An improved local radial point interpolation method for transient heat conduction analysis

    International Nuclear Information System (INIS)

    Wang Feng; Lin Gao; Hu Zhi-Qiang; Zheng Bao-Jing

    2013-01-01

    The smoothing thin plate spline (STPS) interpolation using the penalty function method according to the optimization theory is presented to deal with transient heat conduction problems. The smooth conditions of the shape functions and derivatives can be satisfied so that the distortions hardly occur. Local weak forms are developed using the weighted residual method locally from the partial differential equations of the transient heat conduction. Here the Heaviside step function is used as the test function in each sub-domain to avoid the need for a domain integral. Essential boundary conditions can be implemented like the finite element method (FEM) as the shape functions possess the Kronecker delta property. The traditional two-point difference method is selected for the time discretization scheme. Three selected numerical examples are presented in this paper to demonstrate the availability and accuracy of the present approach comparing with the traditional thin plate spline (TPS) radial basis functions

  17. MAPPING THE SIMILARITIES OF SPECTRA: GLOBAL AND LOCALLY-BIASED APPROACHES TO SDSS GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Lawlor, David [Statistical and Applied Mathematical Sciences Institute (United States); Budavári, Tamás [Dept. of Applied Mathematics and Statistics, The Johns Hopkins University (United States); Mahoney, Michael W. [International Computer Science Institute (United States)

    2016-12-10

    We present a novel approach to studying the diversity of galaxies. It is based on a novel spectral graph technique, that of locally-biased semi-supervised eigenvectors . Our method introduces new coordinates that summarize an entire spectrum, similar to but going well beyond the widely used Principal Component Analysis (PCA). Unlike PCA, however, this technique does not assume that the Euclidean distance between galaxy spectra is a good global measure of similarity. Instead, we relax that condition to only the most similar spectra, and we show that doing so yields more reliable results for many astronomical questions of interest. The global variant of our approach can identify very finely numerous astronomical phenomena of interest. The locally-biased variants of our basic approach enable us to explore subtle trends around a set of chosen objects. The power of the method is demonstrated in the Sloan Digital Sky Survey Main Galaxy Sample, by illustrating that the derived spectral coordinates carry an unprecedented amount of information.

  18. Mapping the Similarities of Spectra: Global and Locally-biased Approaches to SDSS Galaxies

    Science.gov (United States)

    Lawlor, David; Budavári, Tamás; Mahoney, Michael W.

    2016-12-01

    We present a novel approach to studying the diversity of galaxies. It is based on a novel spectral graph technique, that of locally-biased semi-supervised eigenvectors. Our method introduces new coordinates that summarize an entire spectrum, similar to but going well beyond the widely used Principal Component Analysis (PCA). Unlike PCA, however, this technique does not assume that the Euclidean distance between galaxy spectra is a good global measure of similarity. Instead, we relax that condition to only the most similar spectra, and we show that doing so yields more reliable results for many astronomical questions of interest. The global variant of our approach can identify very finely numerous astronomical phenomena of interest. The locally-biased variants of our basic approach enable us to explore subtle trends around a set of chosen objects. The power of the method is demonstrated in the Sloan Digital Sky Survey Main Galaxy Sample, by illustrating that the derived spectral coordinates carry an unprecedented amount of information.

  19. MAPPING THE SIMILARITIES OF SPECTRA: GLOBAL AND LOCALLY-BIASED APPROACHES TO SDSS GALAXIES

    International Nuclear Information System (INIS)

    Lawlor, David; Budavári, Tamás; Mahoney, Michael W.

    2016-01-01

    We present a novel approach to studying the diversity of galaxies. It is based on a novel spectral graph technique, that of locally-biased semi-supervised eigenvectors . Our method introduces new coordinates that summarize an entire spectrum, similar to but going well beyond the widely used Principal Component Analysis (PCA). Unlike PCA, however, this technique does not assume that the Euclidean distance between galaxy spectra is a good global measure of similarity. Instead, we relax that condition to only the most similar spectra, and we show that doing so yields more reliable results for many astronomical questions of interest. The global variant of our approach can identify very finely numerous astronomical phenomena of interest. The locally-biased variants of our basic approach enable us to explore subtle trends around a set of chosen objects. The power of the method is demonstrated in the Sloan Digital Sky Survey Main Galaxy Sample, by illustrating that the derived spectral coordinates carry an unprecedented amount of information.

  20. A new experimental method for determining local airloads on rotor blades in forward flight

    Science.gov (United States)

    Berton, E.; Maresca, C.; Favier, D.

    This paper presents a new approach for determining local airloads on helicopter rotor blade sections in forward flight. The method is based on the momentum equation in which all the terms are expressed by means of the velocity field measured by a laser Doppler velocimeter. The relative magnitude of the different terms involved in the momentum and Bernoulli equations is estimated and the results are encouraging.

  1. The use of mixed-methods research to diagnose the organisational performance of a local government

    Directory of Open Access Journals (Sweden)

    Benjamin H. Olivier

    2017-07-01

    Full Text Available Orientation: The majority of local governments in South Africa are underperforming; a first step to improve their performance is to accurately diagnose their current functioning. The utilisation of a mixed-methods approach for this diagnosis based on a valid model of organisational performance will form a better and holistic understanding of how a local government is performing. Research purpose: The aim of this study is to investigate the utility of mixed-methods research as a diagnostic approach for determining the organisational performance of a local government in South Africa. Motivation for the study: The use of either quantitative or qualitative data gathering in isolation as part of an organisational diagnosis can lead to biased information and not identifying the root causes of problems. The use of mixed-methods research in which both quantitative and qualitative data gathering methods are utilised has been shown to produce numerous benefits, such as confirmation of gathered data, providing richer detail and initiating new lines of thinking. Such multiple methodologies are recognised as an essential component of any organisational diagnosis and can be an effective means of eliminating biases in singular data gathering methods. Research design, approach and method: A concurrent transformative mixed-methods strategy based on the Burke–Litwin model of organisational performance with triangulation of results and findings to determine convergence validity was used. A convenience sample of 116 (N = 203 permanent officials in a rural district municipality in South Africa completed a survey questionnaire and were also individually interviewed. Main findings: Results indicate that mixed-methods research is a valid technique for establishing the integrity of survey data and for providing a better and holistic understanding of the functioning of an organisation. The results also indicate that the Burke–Litwin model is a useful and valid

  2. An approach to the management of locally advanced breast cancer ...

    African Journals Online (AJOL)

    Locally advanced breast cancer (LABC) comprises a heterogeneous group of diseases. It incorporates a subset of stage IIB (T3N0) disease, stage III disease and inflammatory breast cancer. In the developed world, 7% of breast cancer patients have stage III disease at diagnosis. In developing countries, LABC constitutes ...

  3. Laser patterning: A new approach to measure local magneto-transport properties in multifilamentary superconducting tapes

    International Nuclear Information System (INIS)

    Sanchez Valdes, C.F.; Perez-Penichet, C.; Noda, C.; Arronte, M.; Batista-Leyva, A.J.; Haugen, O.; Johansen, T.H.; Han, Z.; Altshuler, E.

    2007-01-01

    The determination of inter- and intra-filament characteristics in superconducting composites such as BSCCO-Ag tapes is of great importance for material evaluation towards applications. Most attempts to separate the two contributions have relied on indirect methods based on magnetic measurements such as SQUID or magneto-optic imaging techniques. Here we show that laser patterning of superconducting BSCCO-Ag tapes constitutes a simple approach to measure local transport properties in a direct way, even able to separate inter- and intra-filament contributions to the overall transport behavior of the sample

  4. The codevelopment of coastal fisheries monitoring methods to support local management

    Directory of Open Access Journals (Sweden)

    Eva Schemmel

    2016-12-01

    Full Text Available Small-scale fisheries across the globe provide critical food security, livelihoods, and human well-being, but are threatened by a combination of local and global stressors, including overexploitation, pollution, and climate change. Participatory approaches to management, especially those that incorporate local communities and customary knowledge can provide meaningful biological information that supports sustainable fisheries management and builds local adaptive capacity to changing ocean conditions. Through a collaboration between fishers, scientists, NGOs, and regulating agencies, we developed a low-cost, low-tech method to assess the seasonal spawning peaks, lunar spawning cycles, and size at maturity (L50 for key targeted reef fish, combining traditional knowledge and practice with modern scientific approaches, including gonadosomatic index (GSI and histology. Two years of community-based monitoring resulted in data from 57 species and 15 families of reef and nearshore fishes (n = 2595, with detailed information for 10 species at 4 locations across the Hawaiian Islands. Comparisons between community-collected GSI data and scientifically (histologically assessed spawning cycles and size at reproductive maturity produced similar results suggesting that these approaches can be applied in data-poor fisheries to assess spawning seasons and size at maturity (L50, both of which are critical needs for effective fisheries management. Semistructured surveys revealed a large body of local knowledge on spawning times and harvest practices based on allowing spawning to occur before harvesting and protecting small and large size classes, but little evidence that fishers understand temporal patterns of spawning. This suggests that monitoring methods that fill key gaps such as this and are congruent with these local knowledge systems and customary harvest practices may be key for local stewardship and adaptive management.

  5. Multicrack Localization in Rotors Based on Proper Orthogonal Decomposition Using Fractal Dimension and Gapped Smoothing Method

    Directory of Open Access Journals (Sweden)

    Zhiwen Lu

    2016-01-01

    Full Text Available Multicrack localization in operating rotor systems is still a challenge today. Focusing on this challenge, a new approach based on proper orthogonal decomposition (POD is proposed for multicrack localization in rotors. A two-disc rotor-bearing system with breathing cracks is established by the finite element method and simulated sensors are distributed along the rotor to obtain the steady-state transverse responses required by POD. Based on the discontinuities introduced in the proper orthogonal modes (POMs at the locations of cracks, the characteristic POM (CPOM, which is sensitive to crack locations and robust to noise, is selected for cracks localization. Instead of using the CPOM directly, due to its difficulty to localize incipient cracks, damage indexes using fractal dimension (FD and gapped smoothing method (GSM are adopted, in order to extract the locations more efficiently. The method proposed in this work is validated to be effective for multicrack localization in rotors by numerical experiments on rotors in different crack configuration cases considering the effects of noise. In addition, the feasibility of using fewer sensors is also investigated.

  6. A new approach for beam hardening correction based on the local spectrum distributions

    International Nuclear Information System (INIS)

    Rasoulpour, Naser; Kamali-Asl, Alireza; Hemmati, Hamidreza

    2015-01-01

    Energy dependence of material absorption and polychromatic nature of x-ray beams in the Computed Tomography (CT) causes a phenomenon which called “beam hardening”. The purpose of this study is to provide a novel approach for Beam Hardening (BH) correction. This approach is based on the linear attenuation coefficients of Local Spectrum Distributions (LSDs) in the various depths of a phantom. The proposed method includes two steps. Firstly, the hardened spectra in various depths of the phantom (or LSDs) are estimated based on the Expectation Maximization (EM) algorithm for arbitrary thickness interval of known materials in the phantom. The performance of LSD estimation technique is evaluated by applying random Gaussian noise to transmission data. Then, the linear attenuation coefficients with regarding to the mean energy of LSDs are obtained. Secondly, a correction function based on the calculated attenuation coefficients is derived in order to correct polychromatic raw data. Since a correction function has been used for the conversion of the polychromatic data to the monochromatic data, the effect of BH in proposed reconstruction must be reduced in comparison with polychromatic reconstruction. The proposed approach has been assessed in the phantoms which involve less than two materials, but the correction function has been extended for using in the constructed phantoms with more than two materials. The relative mean energy difference in the LSDs estimations based on the noise-free transmission data was less than 1.5%. Also, it shows an acceptable value when a random Gaussian noise is applied to the transmission data. The amount of cupping artifact in the proposed reconstruction method has been effectively reduced and proposed reconstruction profile is uniform more than polychromatic reconstruction profile. - Highlights: • A novel Beam Hardening (BH) correction approach was described. • A new concept named Local Spectrum Distributions (LSDs) was used to BH

  7. A new approach for beam hardening correction based on the local spectrum distributions

    Energy Technology Data Exchange (ETDEWEB)

    Rasoulpour, Naser; Kamali-Asl, Alireza, E-mail: a_kamali@sbu.ac.ir; Hemmati, Hamidreza

    2015-09-11

    Energy dependence of material absorption and polychromatic nature of x-ray beams in the Computed Tomography (CT) causes a phenomenon which called “beam hardening”. The purpose of this study is to provide a novel approach for Beam Hardening (BH) correction. This approach is based on the linear attenuation coefficients of Local Spectrum Distributions (LSDs) in the various depths of a phantom. The proposed method includes two steps. Firstly, the hardened spectra in various depths of the phantom (or LSDs) are estimated based on the Expectation Maximization (EM) algorithm for arbitrary thickness interval of known materials in the phantom. The performance of LSD estimation technique is evaluated by applying random Gaussian noise to transmission data. Then, the linear attenuation coefficients with regarding to the mean energy of LSDs are obtained. Secondly, a correction function based on the calculated attenuation coefficients is derived in order to correct polychromatic raw data. Since a correction function has been used for the conversion of the polychromatic data to the monochromatic data, the effect of BH in proposed reconstruction must be reduced in comparison with polychromatic reconstruction. The proposed approach has been assessed in the phantoms which involve less than two materials, but the correction function has been extended for using in the constructed phantoms with more than two materials. The relative mean energy difference in the LSDs estimations based on the noise-free transmission data was less than 1.5%. Also, it shows an acceptable value when a random Gaussian noise is applied to the transmission data. The amount of cupping artifact in the proposed reconstruction method has been effectively reduced and proposed reconstruction profile is uniform more than polychromatic reconstruction profile. - Highlights: • A novel Beam Hardening (BH) correction approach was described. • A new concept named Local Spectrum Distributions (LSDs) was used to BH

  8. Automated local line rolling forming and simplified deformation simulation method for complex curvature plate of ships

    Directory of Open Access Journals (Sweden)

    Y. Zhao

    2017-06-01

    Full Text Available Local line rolling forming is a common forming approach for the complex curvature plate of ships. However, the processing mode based on artificial experience is still applied at present, because it is difficult to integrally determine relational data for the forming shape, processing path, and process parameters used to drive automation equipment. Numerical simulation is currently the major approach for generating such complex relational data. Therefore, a highly precise and effective numerical computation method becomes crucial in the development of the automated local line rolling forming system for producing complex curvature plates used in ships. In this study, a three-dimensional elastoplastic finite element method was first employed to perform numerical computations for local line rolling forming, and the corresponding deformation and strain distribution features were acquired. In addition, according to the characteristics of strain distributions, a simplified deformation simulation method, based on the deformation obtained by applying strain was presented. Compared to the results of the three-dimensional elastoplastic finite element method, this simplified deformation simulation method was verified to provide high computational accuracy, and this could result in a substantial reduction in calculation time. Thus, the application of the simplified deformation simulation method was further explored in the case of multiple rolling loading paths. Moreover, it was also utilized to calculate the local line rolling forming for the typical complex curvature plate of ships. Research findings indicated that the simplified deformation simulation method was an effective tool for rapidly obtaining relationships between the forming shape, processing path, and process parameters.

  9. Local Fractional Variational Iteration and Decomposition Methods for Wave Equation on Cantor Sets within Local Fractional Operators

    Directory of Open Access Journals (Sweden)

    Dumitru Baleanu

    2014-01-01

    Full Text Available We perform a comparison between the fractional iteration and decomposition methods applied to the wave equation on Cantor set. The operators are taken in the local sense. The results illustrate the significant features of the two methods which are both very effective and straightforward for solving the differential equations with local fractional derivative.

  10. A high-resolution computational localization method for transcranial magnetic stimulation mapping.

    Science.gov (United States)

    Aonuma, Shinta; Gomez-Tames, Jose; Laakso, Ilkka; Hirata, Akimasa; Takakura, Tomokazu; Tamura, Manabu; Muragaki, Yoshihiro

    2018-05-15

    Transcranial magnetic stimulation (TMS) is used for the mapping of brain motor functions. The complexity of the brain deters determining the exact localization of the stimulation site using simplified methods (e.g., the region below the center of the TMS coil) or conventional computational approaches. This study aimed to present a high-precision localization method for a specific motor area by synthesizing computed non-uniform current distributions in the brain for multiple sessions of TMS. Peritumoral mapping by TMS was conducted on patients who had intra-axial brain neoplasms located within or close to the motor speech area. The electric field induced by TMS was computed using realistic head models constructed from magnetic resonance images of patients. A post-processing method was implemented to determine a TMS hotspot by combining the computed electric fields for the coil orientations and positions that delivered high motor-evoked potentials during peritumoral mapping. The method was compared to the stimulation site localized via intraoperative direct brain stimulation and navigated TMS. Four main results were obtained: 1) the dependence of the computed hotspot area on the number of peritumoral measurements was evaluated; 2) the estimated localization of the hand motor area in eight non-affected hemispheres was in good agreement with the position of a so-called "hand-knob"; 3) the estimated hotspot areas were not sensitive to variations in tissue conductivity; and 4) the hand motor areas estimated by this proposal and direct electric stimulation (DES) were in good agreement in the ipsilateral hemisphere of four glioma patients. The TMS localization method was validated by well-known positions of the "hand-knob" in brains for the non-affected hemisphere, and by a hotspot localized via DES during awake craniotomy for the tumor-containing hemisphere. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. An approach to the management of locally advanced breast cancer ...

    African Journals Online (AJOL)

    female, aspects surrounding family planning ... surgery and is the current standard of care ... In the developed world, 7% of breast cancer patients have stage III disease at diagnosis. In ... of chemotherapy compared with adjuvant therapy.[6]. Regimens. Historically, regimens based on ... immunohistochemical approach. The.

  12. Periodic local MP2 method employing orbital specific virtuals

    International Nuclear Information System (INIS)

    Usvyat, Denis; Schütz, Martin; Maschio, Lorenzo

    2015-01-01

    We introduce orbital specific virtuals (OSVs) to represent the truncated pair-specific virtual space in periodic local Møller-Plesset perturbation theory of second order (LMP2). The OSVs are constructed by diagonalization of the LMP2 amplitude matrices which correspond to diagonal Wannier-function (WF) pairs. Only a subset of these OSVs is adopted for the subsequent OSV-LMP2 calculation, namely, those with largest contribution to the diagonal pair correlation energy and with the accumulated value of these contributions reaching a certain accuracy. The virtual space for a general (non diagonal) pair is spanned by the union of the two OSV sets related to the individual WFs of the pair. In the periodic LMP2 method, the diagonal LMP2 amplitude matrices needed for the construction of the OSVs are calculated in the basis of projected atomic orbitals (PAOs), employing very large PAO domains. It turns out that the OSVs are excellent to describe short range correlation, yet less appropriate for long range van der Waals correlation. In order to compensate for this bias towards short range correlation, we augment the virtual space spanned by the OSVs by the most diffuse PAOs of the corresponding minimal PAO domain. The Fock and overlap matrices in OSV basis are constructed in the reciprocal space. The 4-index electron repulsion integrals are calculated by local density fitting and, for distant pairs, via multipole approximation. New procedures for determining the fit-domains and the distant-pair lists, leading to higher efficiency in the 4-index integral evaluation, have been implemented. Generally, and in contrast to our previous PAO based periodic LMP2 method, the OSV-LMP2 method does not require anymore great care in the specification of the individual domains (to get a balanced description when calculating energy differences) and is in that sense a black box procedure. Discontinuities in potential energy surfaces, which may occur for PAO-based calculations if one is not

  13. Periodic local MP2 method employing orbital specific virtuals

    Energy Technology Data Exchange (ETDEWEB)

    Usvyat, Denis, E-mail: denis.usvyat@chemie.uni-regensburg.de; Schütz, Martin, E-mail: martin.schuetz@chemie.uni-regensburg.de [Institute for Physical and Theoretical Chemistry, Universität Regensburg, Universitätsstraße 31, D-93040 Regensburg (Germany); Maschio, Lorenzo, E-mail: lorenzo.maschio@unito.it [Dipartimento di Chimica, and Centre of Excellence NIS (Nanostructured Interfaces and Surfaces), Università di Torino, via Giuria 5, I-10125 Torino (Italy)

    2015-09-14

    We introduce orbital specific virtuals (OSVs) to represent the truncated pair-specific virtual space in periodic local Møller-Plesset perturbation theory of second order (LMP2). The OSVs are constructed by diagonalization of the LMP2 amplitude matrices which correspond to diagonal Wannier-function (WF) pairs. Only a subset of these OSVs is adopted for the subsequent OSV-LMP2 calculation, namely, those with largest contribution to the diagonal pair correlation energy and with the accumulated value of these contributions reaching a certain accuracy. The virtual space for a general (non diagonal) pair is spanned by the union of the two OSV sets related to the individual WFs of the pair. In the periodic LMP2 method, the diagonal LMP2 amplitude matrices needed for the construction of the OSVs are calculated in the basis of projected atomic orbitals (PAOs), employing very large PAO domains. It turns out that the OSVs are excellent to describe short range correlation, yet less appropriate for long range van der Waals correlation. In order to compensate for this bias towards short range correlation, we augment the virtual space spanned by the OSVs by the most diffuse PAOs of the corresponding minimal PAO domain. The Fock and overlap matrices in OSV basis are constructed in the reciprocal space. The 4-index electron repulsion integrals are calculated by local density fitting and, for distant pairs, via multipole approximation. New procedures for determining the fit-domains and the distant-pair lists, leading to higher efficiency in the 4-index integral evaluation, have been implemented. Generally, and in contrast to our previous PAO based periodic LMP2 method, the OSV-LMP2 method does not require anymore great care in the specification of the individual domains (to get a balanced description when calculating energy differences) and is in that sense a black box procedure. Discontinuities in potential energy surfaces, which may occur for PAO-based calculations if one is not

  14. An Approach to Teaching Applied GIS: Implementation for Local Organizations.

    Science.gov (United States)

    Benhart, John, Jr.

    2000-01-01

    Describes the instructional method, Client-Life Cycle GIS Project Learning, used in a course at Indiana University of Pennsylvania that enables students to learn with and about geographic information system (GIS). Discusses the course technical issues in GIS and an example project using this method. (CMK)

  15. The morphing method as a flexible tool for adaptive local/non-local simulation of static fracture

    KAUST Repository

    Azdoud, Yan

    2014-04-19

    We introduce a framework that adapts local and non-local continuum models to simulate static fracture problems. Non-local models based on the peridynamic theory are promising for the simulation of fracture, as they allow discontinuities in the displacement field. However, they remain computationally expensive. As an alternative, we develop an adaptive coupling technique based on the morphing method to restrict the non-local model adaptively during the evolution of the fracture. The rest of the structure is described by local continuum mechanics. We conduct all simulations in three dimensions, using the relevant discretization scheme in each domain, i.e., the discontinuous Galerkin finite element method in the peridynamic domain and the continuous finite element method in the local continuum mechanics domain. © 2014 Springer-Verlag Berlin Heidelberg.

  16. Fast approach to evaluate MAP reconstruction for lesion detection and localization

    International Nuclear Information System (INIS)

    Qi, Jinyi; Huesman, Ronald H.

    2004-01-01

    Lesion detection is an important task in emission tomography. Localization ROC (LROC) studies are often used to analyze the lesion detection and localization performance. Most researchers rely on Monte Carlo reconstruction samples to obtain LROC curves, which can be very time-consuming for iterative algorithms. In this paper we develop a fast approach to obtain LROC curves that does not require Monte Carlo reconstructions. We use a channelized Hotelling observer model to search for lesions, and the results can be easily extended to other numerical observers. We theoretically analyzed the mean and covariance of the observer output. Assuming the observer outputs are multivariate Gaussian random variables, an LROC curve can be directly generated by integrating the conditional probability density functions. The high-dimensional integrals are calculated using a Monte Carlo method. The proposed approach is very fast because no iterative reconstruction is involved. Computer simulations show that the results of the proposed method match well with those obtained using the tradition LROC analysis

  17. Rupture Predictions of Notched Ti-6Al-4V Using Local Approaches

    Directory of Open Access Journals (Sweden)

    Mirco Peron

    2018-04-01

    Full Text Available Ti-6Al-4V has been extensively used in structural applications in various engineering fields, from naval to automotive and from aerospace to biomedical. Structural applications are characterized by geometrical discontinuities such as notches, which are widely known to harmfully affect their tensile strength. In recent years, many attempts have been done to define solid criteria with which to reliably predict the tensile strength of materials. Among these criteria, two local approaches are worth mentioning due to the accuracy of their predictions, i.e., the strain energy density (SED approach and the theory of critical distance (TCD method. In this manuscript, the robustness of these two methods in predicting the tensile behavior of notched Ti-6Al-4V specimens has been compared. To this aim, two very dissimilar notch geometries have been tested, i.e., semi-circular and blunt V-notch with a notch root radius equal to 1 mm, and the experimental results have been compared with those predicted by the two models. The experimental values have been estimated with low discrepancies by either the SED approach and the TCD method, but the former results in better predictions. The deviations for the SED are in fact lower than 1.3%, while the TCD provides predictions with errors almost up to 8.5%. Finally, the weaknesses and the strengths of the two models have been reported.

  18. Real-time approaches to the estimation of local wind velocity for a fixed-wing unmanned air vehicle

    International Nuclear Information System (INIS)

    Chan, W L; Lee, C S; Hsiao, F B

    2011-01-01

    Three real-time approaches to estimating local wind velocity for a fixed-wing unmanned air vehicle are presented in this study. All three methods work around the navigation equations with added wind components. The first approach calculates the local wind speed by substituting the ground speed and ascent rate data given by the Global Positioning System (GPS) into the navigation equations. The second and third approaches utilize the extended Kalman filter (EKF) and the unscented Kalman filter (UKF), respectively. The results show that, despite the nonlinearity of the navigation equations, the EKF performance is proven to be on a par with the UKF. A time-varying noise estimation method based on the Wiener filter is also discussed. Results are compared with the average wind speed measured on the ground. All three approaches are proven to be reliable with stated advantages and disadvantages

  19. Local problems; local solutions: an innovative approach to investigating and addressing causes of maternal deaths in Zambia's Copperbelt

    Directory of Open Access Journals (Sweden)

    Hadley Mary B

    2011-05-01

    Full Text Available Abstract Background Maternal mortality in developing countries is high and international targets for reduction are unlikely to be met. Zambia's maternal mortality ratio was 591 per 100,000 live births according to survey data (2007 while routinely collected data captured only about 10% of these deaths. In one district in Zambia medical staff reviewed deaths occurring in the labour ward but no related recommendations were documented nor was there evidence of actions taken to avert further deaths. The Investigate Maternal Deaths and Act (IMDA approach was designed to address these deficiencies and is comprised of four components; identification of maternal deaths; investigation of factors contributing to the deaths; recommendations for action drawn up by multiple stakeholders and monitoring of progress through existing systems. Methods A pilot was conducted in one district of Zambia. Maternal deaths occurring over a period of twelve months were identified and investigated. Data was collected through in-depth interviews with family, focus group discussions and hospital records. The information was summarized and presented at eleven data sharing meetings to key decision makers, during which recommendations for action were drawn up. An output indicator to monitor progress was included in the routine performance assessment tool. High impact interventions were identified using frequency analysis. Results A total of 56 maternal deaths were investigated. Poor communication, existing risk factors, a lack of resources and case management issues were the broad categories under which contributing factors were assigned. Sixty three recommendations were drawn up by key decision-makers of which two thirds were implemented by the end of the pilot period. Potential high impact actions were related to management of AIDS and pregnancy, human resources, referral mechanisms, birth planning at household level and availability of safe blood. Conclusion In resource

  20. Supervisor localization a top-down approach to distributed control of discrete-event systems

    CERN Document Server

    Cai, Kai

    2016-01-01

    This monograph presents a systematic top-down approach to distributed control synthesis of discrete-event systems (DES). The approach is called supervisor localization; its essence is the allocation of external supervisory control action to individual component agents as their internal control strategies. The procedure is: first synthesize a monolithic supervisor, to achieve globally optimal and nonblocking controlled behavior, then decompose the monolithic supervisor into local controllers, one for each agent. The collective behavior of the resulting local controllers is identical to that achieved by the monolithic supervisor. The basic localization theory is first presented in the Ramadge–Wonham language-based supervisory control framework, then demonstrated with distributed control examples of multi-robot formations, manufacturing systems, and distributed algorithms. An architectural approach is adopted to apply localization to large-scale DES; this yields a heterarchical localization procedure, which is...

  1. Real-time prediction of respiratory motion based on local regression methods

    International Nuclear Information System (INIS)

    Ruan, D; Fessler, J A; Balter, J M

    2007-01-01

    Recent developments in modulation techniques enable conformal delivery of radiation doses to small, localized target volumes. One of the challenges in using these techniques is real-time tracking and predicting target motion, which is necessary to accommodate system latencies. For image-guided-radiotherapy systems, it is also desirable to minimize sampling rates to reduce imaging dose. This study focuses on predicting respiratory motion, which can significantly affect lung tumours. Predicting respiratory motion in real-time is challenging, due to the complexity of breathing patterns and the many sources of variability. We propose a prediction method based on local regression. There are three major ingredients of this approach: (1) forming an augmented state space to capture system dynamics, (2) local regression in the augmented space to train the predictor from previous observation data using semi-periodicity of respiratory motion, (3) local weighting adjustment to incorporate fading temporal correlations. To evaluate prediction accuracy, we computed the root mean square error between predicted tumor motion and its observed location for ten patients. For comparison, we also investigated commonly used predictive methods, namely linear prediction, neural networks and Kalman filtering to the same data. The proposed method reduced the prediction error for all imaging rates and latency lengths, particularly for long prediction lengths

  2. RFMix: A Discriminative Modeling Approach for Rapid and Robust Local-Ancestry Inference

    Science.gov (United States)

    Maples, Brian K.; Gravel, Simon; Kenny, Eimear E.; Bustamante, Carlos D.

    2013-01-01

    Local-ancestry inference is an important step in the genetic analysis of fully sequenced human genomes. Current methods can only detect continental-level ancestry (i.e., European versus African versus Asian) accurately even when using millions of markers. Here, we present RFMix, a powerful discriminative modeling approach that is faster (∼30×) and more accurate than existing methods. We accomplish this by using a conditional random field parameterized by random forests trained on reference panels. RFMix is capable of learning from the admixed samples themselves to boost performance and autocorrect phasing errors. RFMix shows high sensitivity and specificity in simulated Hispanics/Latinos and African Americans and admixed Europeans, Africans, and Asians. Finally, we demonstrate that African Americans in HapMap contain modest (but nonzero) levels of Native American ancestry (∼0.4%). PMID:23910464

  3. Modeling local extinction in turbulent combustion using an embedding method

    Science.gov (United States)

    Knaus, Robert; Pantano, Carlos

    2012-11-01

    Local regions of extinction in diffusion flames, called ``flame holes,'' can reduce the efficiency of combustion and increase the production of certain pollutants. At sufficiently high speeds, a flame may also be lifted from the rim of the burner to a downstream location that may be stable. These two phenomena share a common underlying mechanism of propagation related to edge-flame dynamics where chemistry and fluid mechanics are equally important. We present a formulation that describes the formation, propagation, and growth of flames holes on the stoichiometric surface using edge flame dynamics. The boundary separating the flame from the quenched region is modeled using a progress variable defined on the moving stoichiometric surface that is embedded in the three-dimensional space using an extension algorithm. This Cartesian problem is solved using a high-order finite-volume WENO method extended to this nonconservative problem. This algorithm can track the dynamics of flame holes in a turbulent reacting-shear layer and model flame liftoff without requiring full chemistry calculations.

  4. Local linearization methods for the numerical integration of ordinary differential equations: An overview

    International Nuclear Information System (INIS)

    Jimenez, J.C.

    2009-06-01

    Local Linearization (LL) methods conform a class of one-step explicit integrators for ODEs derived from the following primary and common strategy: the vector field of the differential equation is locally (piecewise) approximated through a first-order Taylor expansion at each time step, thus obtaining successive linear equations that are explicitly integrated. Hereafter, the LL approach may include some additional strategies to improve that basic affine approximation. Theoretical and practical results have shown that the LL integrators have a number of convenient properties. These include arbitrary order of convergence, A-stability, linearization preserving, regularity under quite general conditions, preservation of the dynamics of the exact solution around hyperbolic equilibrium points and periodic orbits, integration of stiff and high-dimensional equations, low computational cost, and others. In this paper, a review of the LL methods and their properties is presented. (author)

  5. Determining Coastal Hazards Risk Perception to Enhance Local Mitigation Planning through a Participatory Mapping Approach

    Science.gov (United States)

    Bethel, M.; Braud, D.; Lambeth, T.; Biber, P.; Wu, W.

    2017-12-01

    Coastal community leaders, government officials, and natural resource managers must be able to accurately assess and predict a given coastal landscape's sustainability and/or vulnerability as coastal habitat continues to undergo rapid and dramatic changes associated with natural and anthropogenic activities such as accelerated relative sea level rise (SLR). To help address this information need, a multi-disciplinary project team conducted Sea Grant sponsored research in Louisiana and Mississippi with traditional ecosystem users and natural resource managers to determine a method for producing localized vulnerability and sustainability maps for projected SLR and storm surge impacts, and determine how and whether the results of such an approach can provide more useful information to enhance hazard mitigation planning. The goals of the project are to develop and refine SLR visualization tools for local implementation in areas experiencing subsidence and erosion, and discover the different ways stakeholder groups evaluate risk and plan mitigation strategies associated with projected SLR and storm surge. Results from physical information derived from data and modeling of subsidence, erosion, engineered restoration and coastal protection features, historical land loss, and future land projections under SLR are integrated with complimentary traditional ecological knowledge (TEK) offered by the collaborating local ecosystem users for these assessments. The data analysis involves interviewing stakeholders, coding the interviews for themes, and then converting the themes into vulnerability and sustainability factors. Each factor is weighted according to emphasis by the TEK experts and number of experts who mention it to determine which factors are the highest priority. The priority factors are then mapped with emphasis on the perception of contributing to local community vulnerability or sustainability to SLR and storm surge. The maps are used by the collaborators to benefit

  6. Cloud computing methods and practical approaches

    CERN Document Server

    Mahmood, Zaigham

    2013-01-01

    This book presents both state-of-the-art research developments and practical guidance on approaches, technologies and frameworks for the emerging cloud paradigm. Topics and features: presents the state of the art in cloud technologies, infrastructures, and service delivery and deployment models; discusses relevant theoretical frameworks, practical approaches and suggested methodologies; offers guidance and best practices for the development of cloud-based services and infrastructures, and examines management aspects of cloud computing; reviews consumer perspectives on mobile cloud computing an

  7. Local Analysis Approach for Short Wavelength Geopotential Variations

    Science.gov (United States)

    Bender, P. L.

    2009-12-01

    The value of global spherical harmonic analyses for determining 15 day to 30 day changes in the Earth's gravity field has been demonstrated extensively using data from the GRACE mission and previous missions. However, additional useful information appears to be obtainable from local analyses of the data. A number of such analyses have been carried out by various groups. In the energy approximation, the changes in the height of the satellite altitude geopotential can be determined from the post-fit changes in the satellite separation during individual one-revolution arcs of data from a GRACE-type pair of satellites in a given orbit. For a particular region, it is assumed that short wavelength spatial variations for the arcs crossing that region during a time T of interest would be used to determine corrections to the spherical harmonic results. The main issue in considering higher measurement accuracy in future missions is how much improvement in spatial resolution can be achieved. For this, the shortest wavelengths that can be determined are the most important. And, while the longer wavelength variations are affected by mass distribution changes over much of the globe, the shorter wavelength ones hopefully will be determined mainly by more local changes in the mass distribution. Future missions are expected to have much higher accuracy for measuring changes in the satellite separation than GRACE. However, how large an improvement in the derived results in hydrology will be achieved is still very much a matter of study, particularly because of the effects of uncertainty in the time variations in the atmospheric and oceanic mass distributions. To be specific, it will be assumed that improving the spatial resolution in continental regions away from the coastlines is the objective, and that the satellite altitude is in the range of roughly 290 to 360 km made possible for long missions by drag-free operation. The advantages of putting together the short wavelength

  8. Qualitative Approaches to Mixed Methods Practice

    Science.gov (United States)

    Hesse-Biber, Sharlene

    2010-01-01

    This article discusses how methodological practices can shape and limit how mixed methods is practiced and makes visible the current methodological assumptions embedded in mixed methods practice that can shut down a range of social inquiry. The article argues that there is a "methodological orthodoxy" in how mixed methods is practiced…

  9. Training NOAA Staff on Effective Communication Methods with Local Climate Users

    Science.gov (United States)

    Timofeyeva, M. M.; Mayes, B.

    2011-12-01

    Since 2002 NOAA National Weather Service (NWS) Climate Services Division (CSD) offered training opportunities to NWS staff. As a result of eight-year-long development of the training program, NWS offers three training courses and about 25 online distance learning modules covering various climate topics: climate data and observations, climate variability and change, NWS national and local climate products, their tools, skill, and interpretation. Leveraging climate information and expertise available at all NOAA line offices and partners allows delivery of the most advanced knowledge and is a very critical aspect of the training program. NWS challenges in providing local climate services includes effective communication techniques on provide highly technical scientific information to local users. Addressing this challenge requires well trained, climate-literate workforce at local level capable of communicating the NOAA climate products and services as well as provide climate-sensitive decision support. Trained NWS climate service personnel use proactive and reactive approaches and professional education methods in communicating climate variability and change information to local users. Both scientifically-unimpaired messages and amiable communication techniques such as story telling approach are important in developing an engaged dialog between the climate service providers and users. Several pilot projects NWS CSD conducted in the past year applied the NWS climate services training program to training events for NOAA technical user groups. The technical user groups included natural resources managers, engineers, hydrologists, and planners for transportation infrastructure. Training of professional user groups required tailoring the instructions to the potential applications of each group of users. Training technical user identified the following critical issues: (1) Knowledge of target audience expectations, initial knowledge status, and potential use of climate

  10. Experimental and analytical combined thermal approach for local tribological understanding in metal cutting

    International Nuclear Information System (INIS)

    Artozoul, Julien; Lescalier, Christophe; Dudzinski, Daniel

    2015-01-01

    Metal cutting is a highly complex thermo-mechanical process. The knowledge of temperature in the chip forming zone is essential to understand it. Conventional experimental methods such as thermocouples only provide global information which is incompatible with the high stress and temperature gradients met in the chip forming zone. Field measurements are essential to understand the localized thermo-mechanical problem. An experimental protocol has been developed using advanced infrared imaging in order to measure temperature distribution in both the tool and the chip during an orthogonal or oblique cutting operation. It also provides several information on the chip formation process such as some geometrical characteristics (tool-chip contact length, chip thickness, primary shear angle) and thermo-mechanical information (heat flux dissipated in deformation zone, local interface heat partition ratio). A study is carried out on the effects of cutting conditions i.e. cutting speed, feed and depth of cut on the temperature distribution along the contact zone for an elementary operation. An analytical thermal model has been developed to process experimental data and access more information i.e. local stress or heat flux distribution. - Highlights: • A thermal analytical model is proposed for orthogonal cutting process. • IR thermography is used during cutting tests. • Combined experimental and modeling approaches are applied. • Heat flux and stress distribution at the tool-chip interface are determined. • The decomposition into sticking and sliding zones is defined.

  11. On dynamical systems approaches and methods in f ( R ) cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Alho, Artur [Center for Mathematical Analysis, Geometry and Dynamical Systems, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Carloni, Sante [Centro Multidisciplinar de Astrofisica – CENTRA, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Uggla, Claes, E-mail: aalho@math.ist.utl.pt, E-mail: sante.carloni@tecnico.ulisboa.pt, E-mail: claes.uggla@kau.se [Department of Physics, Karlstad University, S-65188 Karlstad (Sweden)

    2016-08-01

    We discuss dynamical systems approaches and methods applied to flat Robertson-Walker models in f ( R )-gravity. We argue that a complete description of the solution space of a model requires a global state space analysis that motivates globally covering state space adapted variables. This is shown explicitly by an illustrative example, f ( R ) = R + α R {sup 2}, α > 0, for which we introduce new regular dynamical systems on global compactly extended state spaces for the Jordan and Einstein frames. This example also allows us to illustrate several local and global dynamical systems techniques involving, e.g., blow ups of nilpotent fixed points, center manifold analysis, averaging, and use of monotone functions. As a result of applying dynamical systems methods to globally state space adapted dynamical systems formulations, we obtain pictures of the entire solution spaces in both the Jordan and the Einstein frames. This shows, e.g., that due to the domain of the conformal transformation between the Jordan and Einstein frames, not all the solutions in the Jordan frame are completely contained in the Einstein frame. We also make comparisons with previous dynamical systems approaches to f ( R ) cosmology and discuss their advantages and disadvantages.

  12. The active titration method for measuring local hydroxyl radical concentration

    Science.gov (United States)

    Sprengnether, Michele; Prinn, Ronald G.

    1994-01-01

    We are developing a method for measuring ambient OH by monitoring its rate of reaction with a chemical species. Our technique involves the local, instantaneous release of a mixture of saturated cyclic hydrocarbons (titrants) and perfluorocarbons (dispersants). These species must not normally be present in ambient air above the part per trillion concentration. We then track the mixture downwind using a real-time portable ECD tracer instrument. We collect air samples in canisters every few minutes for roughly one hour. We then return to the laboratory and analyze our air samples to determine the ratios of the titrant to dispersant concentrations. The trends in these ratios give us the ambient OH concentration from the relation: dlnR/dt = -k(OH). A successful measurement of OH requires that the trends in these ratios be measureable. We must not perturb ambient OH concentrations. The titrant to dispersant ratio must be spatially invariant. Finally, heterogeneous reactions of our titrant and dispersant species must be negligible relative to the titrant reaction with OH. We have conducted laboratory studies of our ability to measure the titrant to dispersant ratios as a function of concentration down to the few part per trillion concentration. We have subsequently used these results in a gaussian puff model to estimate our expected uncertainty in a field measurement of OH. Our results indicate that under a range of atmospheric conditions we expect to be able to measure OH with a sensitivity of 3x10(exp 5) cm(exp -3). In our most optimistic scenarios, we obtain a sensitivity of 1x10(exp 5) cm(exp -3). These sensitivity values reflect our anticipated ability to measure the ratio trends. However, because we are also using a rate constant to obtain our (OH) from this ratio trend, our accuracy cannot be better than that of the rate constant, which we expect to be about 20 percent.

  13. Integrated approach to improving local CD uniformity in EUV patterning

    Science.gov (United States)

    Liang, Andrew; Hermans, Jan; Tran, Timothy; Viatkina, Katja; Liang, Chen-Wei; Ward, Brandon; Chuang, Steven; Yu, Jengyi; Harm, Greg; Vandereyken, Jelle; Rio, David; Kubis, Michael; Tan, Samantha; Dusa, Mircea; Singhal, Akhil; van Schravendijk, Bart; Dixit, Girish; Shamma, Nader

    2017-03-01

    Extreme ultraviolet (EUV) lithography is crucial to enabling technology scaling in pitch and critical dimension (CD). Currently, one of the key challenges of introducing EUV lithography to high volume manufacturing (HVM) is throughput, which requires high source power and high sensitivity chemically amplified photoresists. Important limiters of high sensitivity chemically amplified resists (CAR) are the effects of photon shot noise and resist blur on the number of photons received and of photoacids generated per feature, especially at the pitches required for 7 nm and 5 nm advanced technology nodes. These stochastic effects are reflected in via structures as hole-to-hole CD variation or local CD uniformity (LCDU). Here, we demonstrate a synergy of film stack deposition, EUV lithography, and plasma etch techniques to improve LCDU, which allows the use of high sensitivity resists required for the introduction of EUV HVM. Thus, to improve LCDU to a level required by 5 nm node and beyond, film stack deposition, EUV lithography, and plasma etch processes were combined and co-optimized to enhance LCDU reduction from synergies. Test wafers were created by depositing a pattern transfer stack on a substrate representative of a 5 nm node target layer. The pattern transfer stack consisted of an atomically smooth adhesion layer and two hardmasks and was deposited using the Lam VECTOR PECVD product family. These layers were designed to mitigate hole roughness, absorb out-of-band radiation, and provide additional outlets for etch to improve LCDU and control hole CD. These wafers were then exposed through an ASML NXE3350B EUV scanner using a variety of advanced positive tone EUV CAR. They were finally etched to the target substrate using Lam Flex dielectric etch and Kiyo conductor etch systems. Metrology methodologies to assess dimensional metrics as well as chip performance and defectivity were investigated to enable repeatable patterning process development. Illumination

  14. Numerical Methods for Stochastic Computations A Spectral Method Approach

    CERN Document Server

    Xiu, Dongbin

    2010-01-01

    The first graduate-level textbook to focus on fundamental aspects of numerical methods for stochastic computations, this book describes the class of numerical methods based on generalized polynomial chaos (gPC). These fast, efficient, and accurate methods are an extension of the classical spectral methods of high-dimensional random spaces. Designed to simulate complex systems subject to random inputs, these methods are widely used in many areas of computer science and engineering. The book introduces polynomial approximation theory and probability theory; describes the basic theory of gPC meth

  15. Radiographic localization of unerupted teeth: further findings about the vertical tube shift method and other localization techniques.

    Science.gov (United States)

    Jacobs, S G

    2000-10-01

    The parallax method (image/tube shift method, Clark's rule, Richards' buccal object rule) is recommended to localize unerupted teeth. Richards' contribution to the development of the parallax method is discussed. The favored method for localization uses a rotational panoramic radiograph in combination with an occlusal radiograph involving a vertical shift of the x-ray tube. The use of this combination when localizing teeth and supernumeraries in the premolar region is illustrated. When taking an occlusal radiograph to localize an unerupted maxillary canine, clinical situations are presented where modification of the vertical angulation of the tube of 70 degrees to 75 degrees or of the horizontal position of the tube is warranted. The limitations of axial (true, cross-sectional, vertex) occlusal radiographs are also explored.

  16. Mixed method approaches to evaluate conservation impact

    DEFF Research Database (Denmark)

    Lund, Jens Friis; Burgess, Neil D.; Chamshama, Shabani A.O.

    2015-01-01

    Nearly 10% of the world's total forest area is formally owned by communities and indigenous groups, yet knowledge of the effects of decentralized forest management approaches on conservation (and livelihood) impacts remains elusive. In this paper, the conservation impact of decentralized forest m...

  17. Fast subcellular localization by cascaded fusion of signal-based and homology-based methods

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2011-10-01

    Full Text Available Abstract Background The functions of proteins are closely related to their subcellular locations. In the post-genomics era, the amount of gene and protein data grows exponentially, which necessitates the prediction of subcellular localization by computational means. Results This paper proposes mitigating the computation burden of alignment-based approaches to subcellular localization prediction by a cascaded fusion of cleavage site prediction and profile alignment. Specifically, the informative segments of protein sequences are identified by a cleavage site predictor using the information in their N-terminal shorting signals. Then, the sequences are truncated at the cleavage site positions, and the shortened sequences are passed to PSI-BLAST for computing their profiles. Subcellular localization are subsequently predicted by a profile-to-profile alignment support-vector-machine (SVM classifier. To further reduce the training and recognition time of the classifier, the SVM classifier is replaced by a new kernel method based on the perturbational discriminant analysis (PDA. Conclusions Experimental results on a new dataset based on Swiss-Prot Release 57.5 show that the method can make use of the best property of signal- and homology-based approaches and can attain an accuracy comparable to that achieved by using full-length sequences. Analysis of profile-alignment score matrices suggest that both profile creation time and profile alignment time can be reduced without significant reduction in subcellular localization accuracy. It was found that PDA enjoys a short training time as compared to the conventional SVM. We advocate that the method will be important for biologists to conduct large-scale protein annotation or for bioinformaticians to perform preliminary investigations on new algorithms that involve pairwise alignments.

  18. A Simple Approach for Local Contact Angle Determination on a Heterogeneous Surface

    KAUST Repository

    Wu, Jinbo; Zhang, Mengying; Wang, Xiang; Li, Shunbo; Wen, Weijia

    2011-01-01

    We report a simple approach for measuring the local contact angle of liquids on a heterogeneous surface consisting of intersected hydrophobic and hydrophilic patch arrays, specifically by employing confocal microscopy and the addition of a very low

  19. Multiple instance learning tracking method with local sparse representation

    KAUST Repository

    Xie, Chengjun; Tan, Jieqing; Chen, Peng; Zhang, Jie; Helg, Lei

    2013-01-01

    as training data for the MIL framework. First, local image patches of a target object are represented as sparse codes with an overcomplete dictionary, where the adaptive representation can be helpful in overcoming partial occlusion in object tracking. Then MIL

  20. Scene Recognition for Indoor Localization Using a Multi-Sensor Fusion Approach

    Directory of Open Access Journals (Sweden)

    Mengyun Liu

    2017-12-01

    Full Text Available After decades of research, there is still no solution for indoor localization like the GNSS (Global Navigation Satellite System solution for outdoor environments. The major reasons for this phenomenon are the complex spatial topology and RF transmission environment. To deal with these problems, an indoor scene constrained method for localization is proposed in this paper, which is inspired by the visual cognition ability of the human brain and the progress in the computer vision field regarding high-level image understanding. Furthermore, a multi-sensor fusion method is implemented on a commercial smartphone including cameras, WiFi and inertial sensors. Compared to former research, the camera on a smartphone is used to “see” which scene the user is in. With this information, a particle filter algorithm constrained by scene information is adopted to determine the final location. For indoor scene recognition, we take advantage of deep learning that has been proven to be highly effective in the computer vision community. For particle filter, both WiFi and magnetic field signals are used to update the weights of particles. Similar to other fingerprinting localization methods, there are two stages in the proposed system, offline training and online localization. In the offline stage, an indoor scene model is trained by Caffe (one of the most popular open source frameworks for deep learning and a fingerprint database is constructed by user trajectories in different scenes. To reduce the volume requirement of training data for deep learning, a fine-tuned method is adopted for model training. In the online stage, a camera in a smartphone is used to recognize the initial scene. Then a particle filter algorithm is used to fuse the sensor data and determine the final location. To prove the effectiveness of the proposed method, an Android client and a web server are implemented. The Android client is used to collect data and locate a user. The web

  1. Geometry optimization of molecules within an LCGTO local-density functional approach

    International Nuclear Information System (INIS)

    Mintmire, J.W.

    1990-01-01

    We describe our implementation of geometry optimization techniques within the linear combination of Gaussian-type orbitals (LCGTO) approach to local-density functional theory. The algorithm for geometry optimization is based on the evaluation of the gradient of the total energy with respect to internal coordinates within the local-density functional scheme. We present optimization results for a range of small molecules which serve as test cases for our approach

  2. Accounting for model error in Bayesian solutions to hydrogeophysical inverse problems using a local basis approach

    Science.gov (United States)

    Irving, J.; Koepke, C.; Elsheikh, A. H.

    2017-12-01

    Bayesian solutions to geophysical and hydrological inverse problems are dependent upon a forward process model linking subsurface parameters to measured data, which is typically assumed to be known perfectly in the inversion procedure. However, in order to make the stochastic solution of the inverse problem computationally tractable using, for example, Markov-chain-Monte-Carlo (MCMC) methods, fast approximations of the forward model are commonly employed. This introduces model error into the problem, which has the potential to significantly bias posterior statistics and hamper data integration efforts if not properly accounted for. Here, we present a new methodology for addressing the issue of model error in Bayesian solutions to hydrogeophysical inverse problems that is geared towards the common case where these errors cannot be effectively characterized globally through some parametric statistical distribution or locally based on interpolation between a small number of computed realizations. Rather than focusing on the construction of a global or local error model, we instead work towards identification of the model-error component of the residual through a projection-based approach. In this regard, pairs of approximate and detailed model runs are stored in a dictionary that grows at a specified rate during the MCMC inversion procedure. At each iteration, a local model-error basis is constructed for the current test set of model parameters using the K-nearest neighbour entries in the dictionary, which is then used to separate the model error from the other error sources before computing the likelihood of the proposed set of model parameters. We demonstrate the performance of our technique on the inversion of synthetic crosshole ground-penetrating radar traveltime data for three different subsurface parameterizations of varying complexity. The synthetic data are generated using the eikonal equation, whereas a straight-ray forward model is assumed in the inversion

  3. New approach to predict photoallergic potentials of chemicals based on murine local lymph node assay.

    Science.gov (United States)

    Maeda, Yosuke; Hirosaki, Haruka; Yamanaka, Hidenori; Takeyoshi, Masahiro

    2018-05-23

    Photoallergic dermatitis, caused by pharmaceuticals and other consumer products, is a very important issue in human health. However, S10 guidelines of the International Conference on Harmonization do not recommend the existing prediction methods for photoallergy because of their low predictability in human cases. We applied local lymph node assay (LLNA), a reliable, quantitative skin sensitization prediction test, to develop a new photoallergy prediction method. This method involves a three-step approach: (1) ultraviolet (UV) absorption analysis; (2) determination of no observed adverse effect level for skin phototoxicity based on LLNA; and (3) photoallergy evaluation based on LLNA. Photoallergic potential of chemicals was evaluated by comparing lymph node cell proliferation among groups treated with chemicals with minimal effect levels of skin sensitization and skin phototoxicity under UV irradiation (UV+) or non-UV irradiation (UV-). A case showing significant difference (P < .05) in lymph node cell proliferation rates between UV- and UV+ groups was considered positive for photoallergic reaction. After testing 13 chemicals, seven human photoallergens tested positive and the other six, with no evidence of causing photoallergic dermatitis or UV absorption, tested negative. Among these chemicals, both doxycycline hydrochloride and minocycline hydrochloride were tetracycline antibiotics with different photoallergic properties, and the new method clearly distinguished between the photoallergic properties of these chemicals. These findings suggested high predictability of our method; therefore, it is promising and effective in predicting human photoallergens. Copyright © 2018 John Wiley & Sons, Ltd.

  4. A "New" Approach to Local Labor Market Analysis: A Feasibility Study.

    Science.gov (United States)

    Goldfarb, Robert; Hamermesh, Daniel

    This report describes research on the New Haven labor market carried out during the summer and fall of 1969 and the spring of 1970. The aims of the research were to develop further the theoretical approach to micro-labor economics in a local labor market and to test the feasibility of collecting data from local firms which could be used to test…

  5. Approaches and methods of risk assessment

    International Nuclear Information System (INIS)

    Rowe, W.D.

    1983-01-01

    The classification system of risk assessment includes the categories: 1) risk comparisons, 2) cost-effectiveness of risk reduction, 3) balancing of costs, risks and benefits against one another, 4. Metasystems. An overview of methods and systems reveals that no single method can be applied to all cases and situations. The visibility of the process and the absolute consideration of all aspects of judging are, however, of first and fore most importance. (DG) [de

  6. Local cell metrics: a novel method for analysis of cell-cell interactions.

    Science.gov (United States)

    Su, Jing; Zapata, Pedro J; Chen, Chien-Chiang; Meredith, J Carson

    2009-10-23

    The regulation of many cell functions is inherently linked to cell-cell contact interactions. However, effects of contact interactions among adherent cells can be difficult to detect with global summary statistics due to the localized nature and noise inherent to cell-cell interactions. The lack of informatics approaches specific for detecting cell-cell interactions is a limitation in the analysis of large sets of cell image data, including traditional and combinatorial or high-throughput studies. Here we introduce a novel histogram-based data analysis strategy, termed local cell metrics (LCMs), which addresses this shortcoming. The new LCM method is demonstrated via a study of contact inhibition of proliferation of MC3T3-E1 osteoblasts. We describe how LCMs can be used to quantify the local environment of cells and how LCMs are decomposed mathematically into metrics specific to each cell type in a culture, e.g., differently-labelled cells in fluorescence imaging. Using this approach, a quantitative, probabilistic description of the contact inhibition effects in MC3T3-E1 cultures has been achieved. We also show how LCMs are related to the naïve Bayes model. Namely, LCMs are Bayes class-conditional probability functions, suggesting their use for data mining and classification. LCMs are successful in robust detection of cell contact inhibition in situations where conventional global statistics fail to do so. The noise due to the random features of cell behavior was suppressed significantly as a result of the focus on local distances, providing sensitive detection of cell-cell contact effects. The methodology can be extended to any quantifiable feature that can be obtained from imaging of cell cultures or tissue samples, including optical, fluorescent, and confocal microscopy. This approach may prove useful in interpreting culture and histological data in fields where cell-cell interactions play a critical role in determining cell fate, e.g., cancer, developmental

  7. A partnership approach to local energy management between European and Asian cities

    International Nuclear Information System (INIS)

    Webber, Peter; Pardo, Manuel; Conway, Stewart; Lack, Don; Ferreira, Vasco; Castanheira, Luis

    2005-01-01

    In Europe, several local areas have a number of years of experience with implementing local energy and greenhouse gas management policies, addressing national and international climate change targets. For example, in the city of Leicester in the UK, local strategies and measures have been implemented over several years to improve the energy efficiency of the Council's own operations and to manage city-wide energy consumption and greenhouse gas emissions. Recently, Leicester has participated in a European Commission funded project, which explores the potential for European local authorities and agencies to use their experience to work with a local area in a developing country where energy demand has been increasing rapidly, addressing climate change and sustainable development issues. The project has aimed to provide support at the local level with developing a framework to minimise energy-related contributions to climate change and air pollution, while giving quality of life benefits. It has used a partnership approach between Leicester, Vila Nova de Gaia municipality in Portugal, and a city in the Gujarat, India. The local level's role in each country in local energy management has been investigated. This has included a baseline assessment of local energy use, renewable energy and climate change issues in each partner city. The most locally relevant energy technologies have been selected and their implementation discussed in the local workshops involving a range of organisations and individuals, with actions being identified to improve the local management of energy, such as raising awareness and ensuring easy access to information

  8. Comparison of methods for genomic localization of gene trap sequences

    Directory of Open Access Journals (Sweden)

    Ferrin Thomas E

    2006-09-01

    Full Text Available Abstract Background Gene knockouts in a model organism such as mouse provide a valuable resource for the study of basic biology and human disease. Determining which gene has been inactivated by an untargeted gene trapping event poses a challenging annotation problem because gene trap sequence tags, which represent sequence near the vector insertion site of a trapped gene, are typically short and often contain unresolved residues. To understand better the localization of these sequences on the mouse genome, we compared stand-alone versions of the alignment programs BLAT, SSAHA, and MegaBLAST. A set of 3,369 sequence tags was aligned to build 34 of the mouse genome using default parameters for each algorithm. Known genome coordinates for the cognate set of full-length genes (1,659 sequences were used to evaluate localization results. Results In general, all three programs performed well in terms of localizing sequences to a general region of the genome, with only relatively subtle errors identified for a small proportion of the sequence tags. However, large differences in performance were noted with regard to correctly identifying exon boundaries. BLAT correctly identified the vast majority of exon boundaries, while SSAHA and MegaBLAST missed the majority of exon boundaries. SSAHA consistently reported the fewest false positives and is the fastest algorithm. MegaBLAST was comparable to BLAT in speed, but was the most susceptible to localizing sequence tags incorrectly to pseudogenes. Conclusion The differences in performance for sequence tags and full-length reference sequences were surprisingly small. Characteristic variations in localization results for each program were noted that affect the localization of sequence at exon boundaries, in particular.

  9. Mathematical models and methods of localized interaction theory

    CERN Document Server

    Bunimovich, AI

    1995-01-01

    The interaction of the environment with a moving body is called "localized" if it has been found or assumed that the force or/and thermal influence of the environment on each body surface point is independent and can be determined by the local geometrical and kinematical characteristics of this point as well as by the parameters of the environment and body-environment interactions which are the same for the whole surface of contact.Such models are widespread in aerodynamics and gas dynamics, covering supersonic and hypersonic flows, and rarefied gas flows. They describe the influence of light

  10. MU-LOC: A Machine-Learning Method for Predicting Mitochondrially Localized Proteins in Plants

    Directory of Open Access Journals (Sweden)

    Ning Zhang

    2018-05-01

    Full Text Available Targeting and translocation of proteins to the appropriate subcellular compartments are crucial for cell organization and function. Newly synthesized proteins are transported to mitochondria with the assistance of complex targeting sequences containing either an N-terminal pre-sequence or a multitude of internal signals. Compared with experimental approaches, computational predictions provide an efficient way to infer subcellular localization of a protein. However, it is still challenging to predict plant mitochondrially localized proteins accurately due to various limitations. Consequently, the performance of current tools can be improved with new data and new machine-learning methods. We present MU-LOC, a novel computational approach for large-scale prediction of plant mitochondrial proteins. We collected a comprehensive dataset of plant subcellular localization, extracted features including amino acid composition, protein position weight matrix, and gene co-expression information, and trained predictors using deep neural network and support vector machine. Benchmarked on two independent datasets, MU-LOC achieved substantial improvements over six state-of-the-art tools for plant mitochondrial targeting prediction. In addition, MU-LOC has the advantage of predicting plant mitochondrial proteins either possessing or lacking N-terminal pre-sequences. We applied MU-LOC to predict candidate mitochondrial proteins for the whole proteome of Arabidopsis and potato. MU-LOC is publicly available at http://mu-loc.org.

  11. Two-Stage Method Based on Local Polynomial Fitting for a Linear Heteroscedastic Regression Model and Its Application in Economics

    Directory of Open Access Journals (Sweden)

    Liyun Su

    2012-01-01

    Full Text Available We introduce the extension of local polynomial fitting to the linear heteroscedastic regression model. Firstly, the local polynomial fitting is applied to estimate heteroscedastic function, then the coefficients of regression model are obtained by using generalized least squares method. One noteworthy feature of our approach is that we avoid the testing for heteroscedasticity by improving the traditional two-stage method. Due to nonparametric technique of local polynomial estimation, we do not need to know the heteroscedastic function. Therefore, we can improve the estimation precision, when the heteroscedastic function is unknown. Furthermore, we focus on comparison of parameters and reach an optimal fitting. Besides, we verify the asymptotic normality of parameters based on numerical simulations. Finally, this approach is applied to a case of economics, and it indicates that our method is surely effective in finite-sample situations.

  12. Dynamical self-arrest in symmetric and asymmetric diblock copolymer melts using a replica approach within a local theory.

    Science.gov (United States)

    Wu, Sangwook

    2009-03-01

    We investigate dynamical self-arrest in a diblock copolymer melt using a replica approach within a self-consistent local method based on dynamical mean-field theory (DMFT). The local replica approach effectively predicts (chiN)_{A} for dynamical self-arrest in a block copolymer melt for symmetric and asymmetric cases. We discuss the competition of the cubic and quartic interactions in the Landau free energy for a block copolymer melt in stabilizing a glassy state depending on the chain length. Our local replica theory provides a universal value for the dynamical self-arrest in block copolymer melts with (chiN)_{A} approximately 10.5+64N;{-3/10} for the symmetric case.

  13. Understanding Global / Local Cultural Leadership : Issues and Methods

    NARCIS (Netherlands)

    Kolsteeg, Johan

    2017-01-01

    Cultural leaders sail between the Scylla and Charibdis of aggregated trans- and supranational cultural-political discourses and the cultural needs of local communities. How do these dynamics influence the work of cultural leaders? How can we understand the work of cultural leaders to connect

  14. Another Method for Localization of Radiolucent Urinary Stones ...

    African Journals Online (AJOL)

    Objectives: 1. To study the feasibility and safety of localization of radiolucent urinary stones during ESWL utilising the refluxing intravesically injected contrast medium along indwelling ureteral stents. 2. To identify the optimum volume of contrast medium and the intravesical pressure at which adequate vesicoureteral reflux ...

  15. Localized atomic basis set in the projector augmented wave method

    DEFF Research Database (Denmark)

    Larsen, Ask Hjorth; Vanin, Marco; Mortensen, Jens Jørgen

    2009-01-01

    We present an implementation of localized atomic-orbital basis sets in the projector augmented wave (PAW) formalism within the density-functional theory. The implementation in the real-space GPAW code provides a complementary basis set to the accurate but computationally more demanding grid...

  16. Bionic Design Methods - A practical approach

    DEFF Research Database (Denmark)

    Kepler, Jørgen Asbøll; Stokholm, Marianne Denise J.

    2004-01-01

    Nature has served as inspiration for product design throughout history. Applications range from poetic translations of form to utilization of primary functional principles. This paper describes a generally applicable design methodology for transforming natural functional principles to feasible...... product design. From a formulation of design demands, which need not necessarily be very precise, the approach continues with a study of natural objects (anaimals, plants) which are subject to the same demands. From this study, the working principle(s) are derived. This (these) are then clarified through...... illustrative models, which should be simplified as much as possible. The simplified principle may now be evaluated and transformed into practical design. The methodology is clarified through examples, taken from a series of extended workshops held atAalborg University ....

  17. A Survey of Sound Source Localization Methods in Wireless Acoustic Sensor Networks

    Directory of Open Access Journals (Sweden)

    Maximo Cobos

    2017-01-01

    Full Text Available Wireless acoustic sensor networks (WASNs are formed by a distributed group of acoustic-sensing devices featuring audio playing and recording capabilities. Current mobile computing platforms offer great possibilities for the design of audio-related applications involving acoustic-sensing nodes. In this context, acoustic source localization is one of the application domains that have attracted the most attention of the research community along the last decades. In general terms, the localization of acoustic sources can be achieved by studying energy and temporal and/or directional features from the incoming sound at different microphones and using a suitable model that relates those features with the spatial location of the source (or sources of interest. This paper reviews common approaches for source localization in WASNs that are focused on different types of acoustic features, namely, the energy of the incoming signals, their time of arrival (TOA or time difference of arrival (TDOA, the direction of arrival (DOA, and the steered response power (SRP resulting from combining multiple microphone signals. Additionally, we discuss methods not only aimed at localizing acoustic sources but also designed to locate the nodes themselves in the network. Finally, we discuss current challenges and frontiers in this field.

  18. Enterprise Engineering Method supporting Six Sigma Approach

    OpenAIRE

    Jochem, Roland

    2007-01-01

    Enterprise Modeling (EM) is currently in operation either as a technique to represent and understand the structure and behavior of the enterprise, or as a technique to analyze business processes, and in many cases as support technique for business process reengineering. However, EM architectures and methodes for Enterprise Engineering can also used to support new management techniques like SIX SIGMA, because these new techniques need a clear, transparent and integrated definition and descript...

  19. (Non-) homomorphic approaches to denoise intensity SAR images with non-local means and stochastic distances

    Science.gov (United States)

    Penna, Pedro A. A.; Mascarenhas, Nelson D. A.

    2018-02-01

    The development of new methods to denoise images still attract researchers, who seek to combat the noise with the minimal loss of resolution and details, like edges and fine structures. Many algorithms have the goal to remove additive white Gaussian noise (AWGN). However, it is not the only type of noise which interferes in the analysis and interpretation of images. Therefore, it is extremely important to expand the filters capacity to different noise models present in li-terature, for example the multiplicative noise called speckle that is present in synthetic aperture radar (SAR) images. The state-of-the-art algorithms in remote sensing area work with similarity between patches. This paper aims to develop two approaches using the non local means (NLM), developed for AWGN. In our research, we expanded its capacity for intensity SAR ima-ges speckle. The first approach is grounded on the use of stochastic distances based on the G0 distribution without transforming the data to the logarithm domain, like homomorphic transformation. It takes into account the speckle and backscatter to estimate the parameters necessary to compute the stochastic distances on NLM. The second method uses a priori NLM denoising with a homomorphic transformation and applies the inverse Gamma distribution to estimate the parameters that were used into NLM with stochastic distances. The latter method also presents a new alternative to compute the parameters for the G0 distribution. Finally, this work compares and analyzes the synthetic and real results of the proposed methods with some recent filters of the literature.

  20. TRANSFER PRICES: MECHANISMS, METHODS AND INTERNATIONAL APPROACHES

    Directory of Open Access Journals (Sweden)

    Pop Cosmina

    2008-05-01

    Full Text Available Transfer prices are considered the prices paid for the goods or services in a cross-border transaction between affiliates companies, often significant reduced or increased in order to avoid the higher imposing rates from one jurisdiction. Presently, over 60% of cross-border transfers are represented by intra-group transfers. The paper presents the variety of methods and mechanisms used by the companies to transfer the funds from one tax jurisdiction to another in order to avoid over taxation.

  1. Microscopic approach to the generator coordinate method

    International Nuclear Information System (INIS)

    Haider, Q.; Gogny, D.; Weiss, M.S.

    1989-01-01

    In this paper, we solve different theoretical problems associated with the calculation of the kernel occurring in the Hill-Wheeler integral equations within the framework of generator coordinate method. In particular, we extend the Wick's theorem to nonorthogonal Bogoliubov states. Expressions for the overlap between Bogoliubov states and for the generalized density matrix are also derived. These expressions are valid even when using an incomplete basis, as in the case of actual calculations. Finally, the Hill-Wheeler formalism is developed for a finite range interaction and the Skyrme force, and evaluated for the latter. 20 refs., 1 fig., 4 tabs

  2. Sumudu transform series expansion method for solving the local fractional Laplace equation in fractal thermal problems

    Directory of Open Access Journals (Sweden)

    Guo Zheng-Hong

    2016-01-01

    Full Text Available In this article, the Sumudu transform series expansion method is used to handle the local fractional Laplace equation arising in the steady fractal heat-transfer problem via local fractional calculus.

  3. Method of center localization for objects containing concentric arcs

    Science.gov (United States)

    Kuznetsova, Elena G.; Shvets, Evgeny A.; Nikolaev, Dmitry P.

    2015-02-01

    This paper proposes a method for automatic center location of objects containing concentric arcs. The method utilizes structure tensor analysis and voting scheme optimized with Fast Hough Transform. Two applications of the proposed method are considered: (i) wheel tracking in video-based system for automatic vehicle classification and (ii) tree growth rings analysis on a tree cross cut image.

  4. Measuring Local Strain Rates In Ductile Shear Zones: A New Approach From Deformed Syntectonic Dykes

    Science.gov (United States)

    Sassier, C.; Leloup, P.; Rubatto, D.; Galland, O.; Yue, Y.; Ding, L.

    2006-12-01

    previous methods. From the less to the most deformed dykes, minimum γ values vary between 0.2 to ~10, respectively. Second, we determined the ages of emplacement of each dyke by ion microprobe U-Pb dating of monazites. We obtained three groups of ages at 22Ma, 24-26Ma and 30Ma. Our geochronological data are in good agreement with our structural data, the most deformed dykes being the oldest. The strain rates deduced from these measurements are on the order of 10^{-14}s-1, that is slower than values previously deduced from indirect methods. However, this value only corresponds to a minimum local strain rate. That new method developed to estimate local minimum strain rates in a major ductile shear zone seems to be reliable and could be applied to other shear zones. Such an approach applied at several locations along a single shear zone could also provide new opportunities to understand the evolution of a whole shear system.

  5. Inverse mass matrix via the method of localized lagrange multipliers

    Czech Academy of Sciences Publication Activity Database

    González, José A.; Kolman, Radek; Cho, S.S.; Felippa, C.A.; Park, K.C.

    2018-01-01

    Roč. 113, č. 2 (2018), s. 277-295 ISSN 0029-5981 R&D Projects: GA MŠk(CZ) EF15_003/0000493; GA ČR GA17-22615S Institutional support: RVO:61388998 Keywords : explicit time integration * inverse mass matrix * localized Lagrange multipliers * partitioned analysis Subject RIV: BI - Acoustics OBOR OECD: Applied mechanics Impact factor: 2.162, year: 2016 https://onlinelibrary.wiley.com/doi/10.1002/nme.5613

  6. Locally linear approximation for Kernel methods : the Railway Kernel

    OpenAIRE

    Muñoz, Alberto; González, Javier

    2008-01-01

    In this paper we present a new kernel, the Railway Kernel, that works properly for general (nonlinear) classification problems, with the interesting property that acts locally as a linear kernel. In this way, we avoid potential problems due to the use of a general purpose kernel, like the RBF kernel, as the high dimension of the induced feature space. As a consequence, following our methodology the number of support vectors is much lower and, therefore, the generalization capab...

  7. Matrix-product-state method with local basis optimization for nonequilibrium electron-phonon systems

    Science.gov (United States)

    Heidrich-Meisner, Fabian; Brockt, Christoph; Dorfner, Florian; Vidmar, Lev; Jeckelmann, Eric

    We present a method for simulating the time evolution of quasi-one-dimensional correlated systems with strongly fluctuating bosonic degrees of freedom (e.g., phonons) using matrix product states. For this purpose we combine the time-evolving block decimation (TEBD) algorithm with a local basis optimization (LBO) approach. We discuss the performance of our approach in comparison to TEBD with a bare boson basis, exact diagonalization, and diagonalization in a limited functional space. TEBD with LBO can reduce the computational cost by orders of magnitude when boson fluctuations are large and thus it allows one to investigate problems that are out of reach of other approaches. First, we test our method on the non-equilibrium dynamics of a Holstein polaron and show that it allows us to study the regime of strong electron-phonon coupling. Second, the method is applied to the scattering of an electronic wave packet off a region with electron-phonon coupling. Our study reveals a rich physics including transient self-trapping and dissipation. Supported by Deutsche Forschungsgemeinschaft (DFG) via FOR 1807.

  8. Bell Operator Method to Classify Local Realistic Theories

    International Nuclear Information System (INIS)

    Nagata, Koji

    2010-01-01

    We review the historical fact of multipartite Bell inequalities with an arbitrary number of settings. An explicit local realistic model for the values of a correlation function, given in a two-setting Bell experiment (two-setting model), works only for the specific set of settings in the given experiment, but cannot construct a local realistic model for the values of a correlation function, given in a continuous-infinite settings Bell experiment (infinite-setting model), even though there exist two-setting models for all directions in space. Hence, the two-setting model does not have the property that the infinite-setting model has. Here, we show that an explicit two-setting model cannot construct a local realistic model for the values of a correlation function, given in an M-setting Bell experiment (M-setting model), even though there exist two-setting models for the M measurement directions chosen in the given M-setting experiment. Hence, the two-setting model does not have the property that the M-setting model has. (general)

  9. SuBSENSE: a universal change detection method with local adaptive sensitivity.

    Science.gov (United States)

    St-Charles, Pierre-Luc; Bilodeau, Guillaume-Alexandre; Bergevin, Robert

    2015-01-01

    Foreground/background segmentation via change detection in video sequences is often used as a stepping stone in high-level analytics and applications. Despite the wide variety of methods that have been proposed for this problem, none has been able to fully address the complex nature of dynamic scenes in real surveillance tasks. In this paper, we present a universal pixel-level segmentation method that relies on spatiotemporal binary features as well as color information to detect changes. This allows camouflaged foreground objects to be detected more easily while most illumination variations are ignored. Besides, instead of using manually set, frame-wide constants to dictate model sensitivity and adaptation speed, we use pixel-level feedback loops to dynamically adjust our method's internal parameters without user intervention. These adjustments are based on the continuous monitoring of model fidelity and local segmentation noise levels. This new approach enables us to outperform all 32 previously tested state-of-the-art methods on the 2012 and 2014 versions of the ChangeDetection.net dataset in terms of overall F-Measure. The use of local binary image descriptors for pixel-level modeling also facilitates high-speed parallel implementations: our own version, which used no low-level or architecture-specific instruction, reached real-time processing speed on a midlevel desktop CPU. A complete C++ implementation based on OpenCV is available online.

  10. Approaches to Mixed Methods Dissemination and Implementation Research: Methods, Strengths, Caveats, and Opportunities.

    Science.gov (United States)

    Green, Carla A; Duan, Naihua; Gibbons, Robert D; Hoagwood, Kimberly E; Palinkas, Lawrence A; Wisdom, Jennifer P

    2015-09-01

    Limited translation of research into practice has prompted study of diffusion and implementation, and development of effective methods of encouraging adoption, dissemination and implementation. Mixed methods techniques offer approaches for assessing and addressing processes affecting implementation of evidence-based interventions. We describe common mixed methods approaches used in dissemination and implementation research, discuss strengths and limitations of mixed methods approaches to data collection, and suggest promising methods not yet widely used in implementation research. We review qualitative, quantitative, and hybrid approaches to mixed methods dissemination and implementation studies, and describe methods for integrating multiple methods to increase depth of understanding while improving reliability and validity of findings.

  11. A sequential mixed methods research approach to investigating HIV ...

    African Journals Online (AJOL)

    2016-09-03

    Sep 3, 2016 ... Sequential mixed methods research is an effective approach for ... show the effectiveness of the research method. ... qualitative data before quantitative datasets ..... whereby both types of data are collected simultaneously.

  12. Modeling of fatigue crack induced nonlinear ultrasonics using a highly parallelized explicit local interaction simulation approach

    Science.gov (United States)

    Shen, Yanfeng; Cesnik, Carlos E. S.

    2016-04-01

    This paper presents a parallelized modeling technique for the efficient simulation of nonlinear ultrasonics introduced by the wave interaction with fatigue cracks. The elastodynamic wave equations with contact effects are formulated using an explicit Local Interaction Simulation Approach (LISA). The LISA formulation is extended to capture the contact-impact phenomena during the wave damage interaction based on the penalty method. A Coulomb friction model is integrated into the computation procedure to capture the stick-slip contact shear motion. The LISA procedure is coded using the Compute Unified Device Architecture (CUDA), which enables the highly parallelized supercomputing on powerful graphic cards. Both the explicit contact formulation and the parallel feature facilitates LISA's superb computational efficiency over the conventional finite element method (FEM). The theoretical formulations based on the penalty method is introduced and a guideline for the proper choice of the contact stiffness is given. The convergence behavior of the solution under various contact stiffness values is examined. A numerical benchmark problem is used to investigate the new LISA formulation and results are compared with a conventional contact finite element solution. Various nonlinear ultrasonic phenomena are successfully captured using this contact LISA formulation, including the generation of nonlinear higher harmonic responses. Nonlinear mode conversion of guided waves at fatigue cracks is also studied.

  13. A demodulating approach based on local mean decomposition and its applications in mechanical fault diagnosis

    International Nuclear Information System (INIS)

    Chen, Baojia; He, Zhengjia; Chen, Xuefeng; Cao, Hongrui; Cai, Gaigai; Zi, Yanyang

    2011-01-01

    Since machinery fault vibration signals are usually multicomponent modulation signals, how to decompose complex signals into a set of mono-components whose instantaneous frequency (IF) has physical sense has become a key issue. Local mean decomposition (LMD) is a new kind of time–frequency analysis approach which can decompose a signal adaptively into a set of product function (PF) components. In this paper, a modulation feature extraction method-based LMD is proposed. The envelope of a PF is the instantaneous amplitude (IA) and the derivative of the unwrapped phase of a purely flat frequency demodulated (FM) signal is the IF. The computed IF and IA are displayed together in the form of time–frequency representation (TFR). Modulation features can be extracted from the spectrum analysis of the IA and IF. In order to make the IF have physical meaning, the phase-unwrapping algorithm and IF processing method of extrema are presented in detail along with a simulation FM signal example. Besides, the dependence of the LMD method on the signal-to-noise ratio (SNR) is also investigated by analyzing synthetic signals which are added with Gaussian noise. As a result, the recommended critical SNRs for PF decomposition and IF extraction are given according to the practical application. Successful fault diagnosis on a rolling bearing and gear of locomotive bogies shows that LMD has better identification capacity for modulation signal processing and is very suitable for failure detection in rotating machinery

  14. An Information-Based Approach to Precision Analysis of Indoor WLAN Localization Using Location Fingerprint

    Directory of Open Access Journals (Sweden)

    Mu Zhou

    2015-12-01

    Full Text Available In this paper, we proposed a novel information-based approach to precision analysis of indoor wireless local area network (WLAN localization using location fingerprint. First of all, by using the Fisher information matrix (FIM, we derive the fundamental limit of WLAN fingerprint-based localization precision considering different signal distributions in characterizing the variation of received signal strengths (RSSs in the target environment. After that, we explore the relationship between the localization precision and access point (AP placement, which can provide valuable suggestions for the design of the highly-precise localization system. Second, we adopt the heuristic simulated annealing (SA algorithm to optimize the AP locations for the sake of approaching the fundamental limit of localization precision. Finally, the extensive simulations and experiments are conducted in both regular line-of-sight (LOS and irregular non-line-of-sight (NLOS environments to demonstrate that the proposed approach can not only effectively improve the WLAN fingerprint-based localization precision, but also reduce the time overhead.

  15. A Least Square-Based Self-Adaptive Localization Method for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Baoguo Yu

    2016-01-01

    Full Text Available In the wireless sensor network (WSN localization methods based on Received Signal Strength Indicator (RSSI, it is usually required to determine the parameters of the radio signal propagation model before estimating the distance between the anchor node and an unknown node with reference to their communication RSSI value. And finally we use a localization algorithm to estimate the location of the unknown node. However, this localization method, though high in localization accuracy, has weaknesses such as complex working procedure and poor system versatility. Concerning these defects, a self-adaptive WSN localization method based on least square is proposed, which uses the least square criterion to estimate the parameters of radio signal propagation model, which positively reduces the computation amount in the estimation process. The experimental results show that the proposed self-adaptive localization method outputs a high processing efficiency while satisfying the high localization accuracy requirement. Conclusively, the proposed method is of definite practical value.

  16. First-principles modeling of localized d states with the GW@LDA+U approach

    Science.gov (United States)

    Jiang, Hong; Gomez-Abal, Ricardo I.; Rinke, Patrick; Scheffler, Matthias

    2010-07-01

    First-principles modeling of systems with localized d states is currently a great challenge in condensed-matter physics. Density-functional theory in the standard local-density approximation (LDA) proves to be problematic. This can be partly overcome by including local Hubbard U corrections (LDA+U) but itinerant states are still treated on the LDA level. Many-body perturbation theory in the GW approach offers both a quasiparticle perspective (appropriate for itinerant states) and an exact treatment of exchange (appropriate for localized states), and is therefore promising for these systems. LDA+U has previously been viewed as an approximate GW scheme. We present here a derivation that is simpler and more general, starting from the static Coulomb-hole and screened exchange approximation to the GW self-energy. Following our previous work for f -electron systems [H. Jiang, R. I. Gomez-Abal, P. Rinke, and M. Scheffler, Phys. Rev. Lett. 102, 126403 (2009)10.1103/PhysRevLett.102.126403] we conduct a systematic investigation of the GW method based on LDA+U(GW@LDA+U) , as implemented in our recently developed all-electron GW code FHI-gap (Green’s function with augmented plane waves) for a series of prototypical d -electron systems: (1) ScN with empty d states, (2) ZnS with semicore d states, and (3) late transition-metal oxides (MnO, FeO, CoO, and NiO) with partially occupied d states. We show that for ZnS and ScN, the GW band gaps only weakly depend on U but for the other transition-metal oxides the dependence on U is as strong as in LDA+U . These different trends can be understood in terms of changes in the hybridization and screening. Our work demonstrates that GW@LDA+U with “physical” values of U provides a balanced and accurate description of both localized and itinerant states.

  17. Signal Processing for Nondifferentiable Data Defined on Cantor Sets: A Local Fractional Fourier Series Approach

    Directory of Open Access Journals (Sweden)

    Zhi-Yong Chen

    2014-01-01

    Full Text Available From the signal processing point of view, the nondifferentiable data defined on the Cantor sets are investigated in this paper. The local fractional Fourier series is used to process the signals, which are the local fractional continuous functions. Our results can be observed as significant extensions of the previously known results for the Fourier series in the framework of the local fractional calculus. Some examples are given to illustrate the efficiency and implementation of the present method.

  18. An ESPRIT-Based Approach for 2-D Localization of Incoherently Distributed Sources in Massive MIMO Systems

    Science.gov (United States)

    Hu, Anzhong; Lv, Tiejun; Gao, Hui; Zhang, Zhang; Yang, Shaoshi

    2014-10-01

    In this paper, an approach of estimating signal parameters via rotational invariance technique (ESPRIT) is proposed for two-dimensional (2-D) localization of incoherently distributed (ID) sources in large-scale/massive multiple-input multiple-output (MIMO) systems. The traditional ESPRIT-based methods are valid only for one-dimensional (1-D) localization of the ID sources. By contrast, in the proposed approach the signal subspace is constructed for estimating the nominal azimuth and elevation direction-of-arrivals and the angular spreads. The proposed estimator enjoys closed-form expressions and hence it bypasses the searching over the entire feasible field. Therefore, it imposes significantly lower computational complexity than the conventional 2-D estimation approaches. Our analysis shows that the estimation performance of the proposed approach improves when the large-scale/massive MIMO systems are employed. The approximate Cram\\'{e}r-Rao bound of the proposed estimator for the 2-D localization is also derived. Numerical results demonstrate that albeit the proposed estimation method is comparable with the traditional 2-D estimators in terms of performance, it benefits from a remarkably lower computational complexity.

  19. A comparative analysis of ecosystem services valuation approaches for application at the local scale and in data scarce regions

    OpenAIRE

    Pandeya, B.; Buytaert, W.; Zulkafli, Z.; Karpouzoglou, T.; Mao, F.; Hannah, D.M.

    2016-01-01

    Despite significant advances in the development of the ecosystem services concept across the science and policy arenas, the valuation of ecosystem services to guide sustainable development remains challenging, especially at a local scale and in data scarce regions. In this paper, we review and compare major past and current valuation approaches and discuss their key strengths and weaknesses for guiding policy decisions. To deal with the complexity of methods used in different valuation approa...

  20. Study of revitalisation methods on anthropogenic soils - Stara Beta locality

    International Nuclear Information System (INIS)

    Svec, J.

    2003-01-01

    Coal mining in Krusne Mts. region is significant anthropogenic pressure. Thus it is necessary to restore land devastated by mining and to bring back its natural functions. Since 2002 locality of Stara Beta, Jan Sverma quarry hopper is being monitored. In 1992 restoration works at Stara Beta were opened. Monitoring is aimed at evaluation development of restoration processes, soil and vegetation caring. Areas where restoration works are realized represent about 60 square kilometres in Most district. The aim is to prepare necessary groundwork for methodology on caring of wood vegetation on restored areas

  1. Predicting protein complexes using a supervised learning method combined with local structural information.

    Science.gov (United States)

    Dong, Yadong; Sun, Yongqi; Qin, Chao

    2018-01-01

    The existing protein complex detection methods can be broadly divided into two categories: unsupervised and supervised learning methods. Most of the unsupervised learning methods assume that protein complexes are in dense regions of protein-protein interaction (PPI) networks even though many true complexes are not dense subgraphs. Supervised learning methods utilize the informative properties of known complexes; they often extract features from existing complexes and then use the features to train a classification model. The trained model is used to guide the search process for new complexes. However, insufficient extracted features, noise in the PPI data and the incompleteness of complex data make the classification model imprecise. Consequently, the classification model is not sufficient for guiding the detection of complexes. Therefore, we propose a new robust score function that combines the classification model with local structural information. Based on the score function, we provide a search method that works both forwards and backwards. The results from experiments on six benchmark PPI datasets and three protein complex datasets show that our approach can achieve better performance compared with the state-of-the-art supervised, semi-supervised and unsupervised methods for protein complex detection, occasionally significantly outperforming such methods.

  2. Improved radiological/nuclear source localization in variable NORM background: An MLEM approach with segmentation data

    Energy Technology Data Exchange (ETDEWEB)

    Penny, Robert D., E-mail: robert.d.penny@leidos.com [Leidos Inc., 10260 Campus Point Road, San Diego, CA (United States); Crowley, Tanya M.; Gardner, Barbara M.; Mandell, Myron J.; Guo, Yanlin; Haas, Eric B.; Knize, Duane J.; Kuharski, Robert A.; Ranta, Dale; Shyffer, Ryan [Leidos Inc., 10260 Campus Point Road, San Diego, CA (United States); Labov, Simon; Nelson, Karl; Seilhan, Brandon [Lawrence Livermore National Laboratory, Livermore, CA (United States); Valentine, John D. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2015-06-01

    A novel approach and algorithm have been developed to rapidly detect and localize both moving and static radiological/nuclear (R/N) sources from an airborne platform. Current aerial systems with radiological sensors are limited in their ability to compensate for variable naturally occurring radioactive material (NORM) background. The proposed approach suppresses the effects of NORM background by incorporating additional information to segment the survey area into regions over which the background is likely to be uniform. The method produces pixelated Source Activity Maps (SAMs) of both target and background radionuclide activity over the survey area. The task of producing the SAMs requires (1) the development of a forward model which describes the transformation of radionuclide activity to detector measurements and (2) the solution of the associated inverse problem. The inverse problem is ill-posed as there are typically fewer measurements than unknowns. In addition the measurements are subject to Poisson statistical noise. The Maximum-Likelihood Expectation-Maximization (MLEM) algorithm is used to solve the inverse problem as it is well suited for under-determined problems corrupted by Poisson noise. A priori terrain information is incorporated to segment the reconstruction space into regions within which we constrain NORM background activity to be uniform. Descriptions of the algorithm and examples of performance with and without segmentation on simulated data are presented.

  3. Finding fossils in new ways: an artificial neural network approach to predicting the location of productive fossil localities.

    Science.gov (United States)

    Anemone, Robert; Emerson, Charles; Conroy, Glenn

    2011-01-01

    Chance and serendipity have long played a role in the location of productive fossil localities by vertebrate paleontologists and paleoanthropologists. We offer an alternative approach, informed by methods borrowed from the geographic information sciences and using recent advances in computer science, to more efficiently predict where fossil localities might be found. Our model uses an artificial neural network (ANN) that is trained to recognize the spectral characteristics of known productive localities and other land cover classes, such as forest, wetlands, and scrubland, within a study area based on the analysis of remotely sensed (RS) imagery. Using these spectral signatures, the model then classifies other pixels throughout the study area. The results of the neural network classification can be examined and further manipulated within a geographic information systems (GIS) software package. While we have developed and tested this model on fossil mammal localities in deposits of Paleocene and Eocene age in the Great Divide Basin of southwestern Wyoming, a similar analytical approach can be easily applied to fossil-bearing sedimentary deposits of any age in any part of the world. We suggest that new analytical tools and methods of the geographic sciences, including remote sensing and geographic information systems, are poised to greatly enrich paleoanthropological investigations, and that these new methods should be embraced by field workers in the search for, and geospatial analysis of, fossil primates and hominins. Copyright © 2011 Wiley-Liss, Inc.

  4. Use of the Local Variation Methods for Nuclear Design Calculations

    International Nuclear Information System (INIS)

    Zhukov, A.I.

    2006-01-01

    A new problem-solving method for steady-state equations, which describe neutron diffusion, is presented. The method bases on a variation principal for steady-state diffusion equations and direct search the minimum of a corresponding functional. Benchmark problem calculation for power of fuel assemblies show ∼ 2% relative accuracy

  5. A machine learning approach for efficient uncertainty quantification using multiscale methods

    Science.gov (United States)

    Chan, Shing; Elsheikh, Ahmed H.

    2018-02-01

    Several multiscale methods account for sub-grid scale features using coarse scale basis functions. For example, in the Multiscale Finite Volume method the coarse scale basis functions are obtained by solving a set of local problems over dual-grid cells. We introduce a data-driven approach for the estimation of these coarse scale basis functions. Specifically, we employ a neural network predictor fitted using a set of solution samples from which it learns to generate subsequent basis functions at a lower computational cost than solving the local problems. The computational advantage of this approach is realized for uncertainty quantification tasks where a large number of realizations has to be evaluated. We attribute the ability to learn these basis functions to the modularity of the local problems and the redundancy of the permeability patches between samples. The proposed method is evaluated on elliptic problems yielding very promising results.

  6. Steepest descent method for set-valued locally accretive mappings

    International Nuclear Information System (INIS)

    Chidume, C.E.

    1993-05-01

    Let E be a real q-uniformly smooth Banach space. Suppose T is a set-valued locally strongly accretive map with open domain D(T) in E and that 0 is an element of Tx has a solution x* in D(T). Then there exists a neighbourhood B in D(T) of x* and a real number r 1 >0 such that for any r>r 1 and some real sequence {c n }, any initial guess x 1 is an element of B and any single-valued selection T 0 of T, the sequence {x n } generated from x 1 by x n+1 =x n -c n T 0 x n , n≥1, remains in D(T) and converges strongly to x* with ||x n -x*|| O(n -(q-1)/ q). A related result deals with iterative approximation of a solution of the equation f is an element of x+Ax when A is a locally accretive map. Our theorems generalize important known results and resolve a problem of interest. (author). 39 refs

  7. Variational local moment approach: From Kondo effect to Mott transition in correlated electron systems

    International Nuclear Information System (INIS)

    Kauch, Anna; Byczuk, Krzysztof

    2012-01-01

    The variational local moment approach (VLMA) solution of the single impurity Anderson model is presented. It generalizes the local moment approach of Logan et al. by invoking the variational principle to determine the lengths of local moments and orbital occupancies. We show that VLMA is a comprehensive, conserving and thermodynamically consistent approximation and treats both Fermi and non-Fermi liquid regimes as well as local moment phases on equal footing. We tested VLMA on selected problems. We solved the single- and multi-orbital impurity Anderson model in various regions of parameters, where different types of Kondo effects occur. The application of VLMA as an impurity solver of the dynamical mean-field theory, used to solve the multi-orbital Hubbard model, is also addressed.

  8. Combination of retrograde superselective intra-arterial chemotherapy and Seldinger method in locally advanced oral cancer

    Directory of Open Access Journals (Sweden)

    Masataka Uehara

    2015-01-01

    Full Text Available The nonsurgical strategies for locally advanced oral cancer are desirable. Superselective intra-arterial infusion with radiotherapy was utilized for this purpose, and there are two types of superselective intra-arterial infusion methods: The Seldinger method and the retrograde superselective intra-arterial chemotherapy (HFT method. In one case, the HFT method was applied to locally advanced tongue cancer, and the Seldinger method was used for additional administration of cisplatin (CDDP to compensate for a lack of drug flow in the HFT method. In another case, the HFT method was applied to locally advanced lower gingival cancer. The Seldinger method was applied to metastatic lymph nodes. In both cases, additional administration of CDDP using the Seldinger method resulted in a complete response. The combination of the HFT and Seldinger methods was useful to eradicate locally advanced oral cancer because each method compensated for the defects of the other.

  9. Method of preliminary localization of the iris in biometric access control systems

    Science.gov (United States)

    Minacova, N.; Petrov, I.

    2015-10-01

    This paper presents a method of preliminary localization of the iris, based on the stable brightness features of the iris in images of the eye. In tests on images of eyes from publicly available databases method showed good accuracy and speed compared to existing methods preliminary localization.

  10. Intergranular brittle fracture of a low alloy steel. Global and local approaches

    International Nuclear Information System (INIS)

    Kantidis, E.

    1993-08-01

    The intergranular brittle fracture of a low alloy steel (A533B.Cl1) is studied: an embrittlement heat treatment is used to develop two brittle 'states' that fail through an intergranular way at low temperatures. This mode of fracture leads to an important shift of the transition temperature (∼ 165 deg C) and a decrease in the fracture toughness. The local approach to fracture, developed for cleavage, is applied to the case of intergranular fracture. Modifications are proposed. The physical supports of these models are verified by biaxial (tension-torsion) tests. From the local approaches developed for intergranular fracture, the static and dynamic fracture toughness of the embrittled steel is predicted. The local approach applied to a structural steel, which presents mixed modes of fracture (cleavage and intergranular), showed that this mode of fracture seems to be controlled by intergranular loss of cohesion

  11. A Feedforward Control Approach to the Local Navigation Problem for Autonomous Vehicles

    Science.gov (United States)

    1994-05-02

    AD-A282 787 " A Feedforward Control Approach to the Local Navigation Problem for Autonomous Vehicles Alonzo Kelly CMU-RI-TR-94-17 The Robotics...follow, or a direction to prefer, it cannot generate its own strategic goals. Therefore, it solves the local planning problem for autonomous vehicles . The... autonomous vehicles . It is intelligent because it uses range images that are generated from either a laser rangefinder or a stereo triangulation

  12. Towards Multi-Method Research Approach in Empirical Software Engineering

    Science.gov (United States)

    Mandić, Vladimir; Markkula, Jouni; Oivo, Markku

    This paper presents results of a literature analysis on Empirical Research Approaches in Software Engineering (SE). The analysis explores reasons why traditional methods, such as statistical hypothesis testing and experiment replication are weakly utilized in the field of SE. It appears that basic assumptions and preconditions of the traditional methods are contradicting the actual situation in the SE. Furthermore, we have identified main issues that should be considered by the researcher when selecting the research approach. In virtue of reasons for weak utilization of traditional methods we propose stronger use of Multi-Method approach with Pragmatism as the philosophical standpoint.

  13. New Keypoint Matching Method Using Local Convolutional Features for Power Transmission Line Icing Monitoring

    Directory of Open Access Journals (Sweden)

    Qiangliang Guo

    2018-02-01

    Full Text Available Power transmission line icing (PTLI problems, which cause tremendous damage to the power grids, has drawn much attention. Existing three-dimensional measurement methods based on binocular stereo vision was recently introduced to measure the ice thickness in PTLI, but failed to meet requirements of practical applications due to inefficient keypoint matching in the complex PTLI scene. In this paper, a new keypoint matching method is proposed based on the local multi-layer convolutional neural network (CNN features, termed Local Convolutional Features (LCFs. LCFs are deployed to extract more discriminative features than the conventional CNNs. Particularly in LCFs, a multi-layer features fusion scheme is exploited to boost the matching performance. Together with a location constraint method, the correspondence of neighboring keypoints is further refined. Our approach achieves 1.5%, 5.3%, 13.1%, 27.3% improvement in the average matching precision compared with SIFT, SURF, ORB and MatchNet on the public Middlebury dataset, and the measurement accuracy of ice thickness can reach 90.9% compared with manual measurement on the collected PTLI dataset.

  14. Local Strategy Combined with a Wavelength Selection Method for Multivariate Calibration

    Directory of Open Access Journals (Sweden)

    Haitao Chang

    2016-06-01

    Full Text Available One of the essential factors influencing the prediction accuracy of multivariate calibration models is the quality of the calibration data. A local regression strategy, together with a wavelength selection approach, is proposed to build the multivariate calibration models based on partial least squares regression. The local algorithm is applied to create a calibration set of spectra similar to the spectrum of an unknown sample; the synthetic degree of grey relation coefficient is used to evaluate the similarity. A wavelength selection method based on simple-to-use interactive self-modeling mixture analysis minimizes the influence of noisy variables, and the most informative variables of the most similar samples are selected to build the multivariate calibration model based on partial least squares regression. To validate the performance of the proposed method, ultraviolet-visible absorbance spectra of mixed solutions of food coloring analytes in a concentration range of 20–200 µg/mL is measured. Experimental results show that the proposed method can not only enhance the prediction accuracy of the calibration model, but also greatly reduce its complexity.

  15. A matrix structured LED backlight system with 2D-DHT local dimming method

    Science.gov (United States)

    Liu, Jia; Li, Yang; Du, Sidan

    To reduce the number of the drivers in the conventional local dimming method for LCDs, a novel LED backlight local dimming system is proposed in this paper. The backlight of this system is generated by 2D discrete Hadamard transform and its matrix structured LED modules. Compared with the conventional 2D local dimming method, the proposed method costs much fewer drivers but with little degradation.

  16. A fast template matching method for LED chip Localization

    Directory of Open Access Journals (Sweden)

    Zhong Fuqiang

    2015-01-01

    Full Text Available Efficiency determines the profits of the semiconductor producers. So the producers spare no effort to enhance the efficiency of every procedure. The purpose of the paper is to present a method to shorten the time to locate the LED chips on wafer. The method consists of 3 steps. Firstly, image segmentation and blob analyzation are used to predict the positions of potential chips. Then predict the orientations of potential chips based on their dominant orientations. Finally, according to the positions and orientations predicted above, locate the chips precisely based on gradient orientation features. Experiments show that the algorithm is faster than the traditional method we choose to locate the LED chips. Besides, even the orientations of the chips on wafer are of big deviation to the orientation of the template, the efficiency of this method won't be affected.

  17. Statistical Genetics Methods for Localizing Multiple Breast Cancer Genes

    National Research Council Canada - National Science Library

    Ott, Jurg

    1998-01-01

    .... For a number of variables measured on a trait, a method, principal components of heritability, was developed that combines these variables in such a way that the resulting linear combination has highest heritability...

  18. Localized surface plasmon resonance mercury detection system and methods

    Science.gov (United States)

    James, Jay; Lucas, Donald; Crosby, Jeffrey Scott; Koshland, Catherine P.

    2016-03-22

    A mercury detection system that includes a flow cell having a mercury sensor, a light source and a light detector is provided. The mercury sensor includes a transparent substrate and a submonolayer of mercury absorbing nanoparticles, e.g., gold nanoparticles, on a surface of the substrate. Methods of determining whether mercury is present in a sample using the mercury sensors are also provided. The subject mercury detection systems and methods find use in a variety of different applications, including mercury detecting applications.

  19. GPU-based local interaction simulation approach for simplified temperature effect modelling in Lamb wave propagation used for damage detection

    International Nuclear Information System (INIS)

    Kijanka, P; Radecki, R; Packo, P; Staszewski, W J; Uhl, T

    2013-01-01

    Temperature has a significant effect on Lamb wave propagation. It is important to compensate for this effect when the method is considered for structural damage detection. The paper explores a newly proposed, very efficient numerical simulation tool for Lamb wave propagation modelling in aluminum plates exposed to temperature changes. A local interaction approach implemented with a parallel computing architecture and graphics cards is used for these numerical simulations. The numerical results are compared with the experimental data. The results demonstrate that the proposed approach could be used efficiently to produce a large database required for the development of various temperature compensation procedures in structural health monitoring applications. (paper)

  20. A NEW APPROACH REGARDING THE EXPENSES IN LOCAL BUDGETS FOR PUBLIC AUTHORITIES

    Directory of Open Access Journals (Sweden)

    CRISTINEL ICHIM

    2013-02-01

    Full Text Available The present study proposes a new approach regarding the expenditures for public authorities covered by localbudgets to streamline their positive impact on the improvment of the financial activitiy of local administrations. Thestudy begins with fixing the place of these expenses within the sphere of public costs from the local budget and continueswith presenting the new legislative framework of their manifestation. In the last part of the study I conceived twoalternatives to reduce the costs involved in the functioning of the local administrative system closely correlated with theterritorial and administrative reorganization of Romania.

  1. IMPACT OF SOCIAL CAPITAL CHARACTERISTICS ON THE EFFECTIVENESS OF COMMUNITY-BASED APPROACH TO LOCAL DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    N. Grazhevska

    2013-10-01

    Full Text Available The article examines the impact of social capital characteristics of local communities on the effectiveness of the community-based approach to economic development. The conclusion that such social capital characteristics as (antipaternalism, solidarity and cooperation have the greatest importance for the economic development is made based on the analysis of UNDP and the European Union project “Community-based approach to local development”. It was hypothesized that the creation of community organizations could be an effective mechanism to actualize the existing social capital of rural communities in Ukraine.

  2. Acoustic emission localization on ship hull structures using a deep learning approach

    DEFF Research Database (Denmark)

    Georgoulas, George; Kappatos, Vassilios; Nikolakopoulos, George

    2016-01-01

    In this paper, deep belief networks were used for localization of acoustic emission events on ship hull structures. In order to avoid complex and time consuming implementations, the proposed approach uses a simple feature extraction module, which significantly reduces the extremely high dimension......In this paper, deep belief networks were used for localization of acoustic emission events on ship hull structures. In order to avoid complex and time consuming implementations, the proposed approach uses a simple feature extraction module, which significantly reduces the extremely high...

  3. Tests of Local Hadron Calibration Approaches in ATLAS Combined Beam Tests

    International Nuclear Information System (INIS)

    Grahn, Karl-Johan; Kiryunin, Andrey; Pospelov, Guennadi

    2011-01-01

    Three ATLAS calorimeters in the region of the forward crack at |η| 3.2 in the nominal ATLAS setup and a typical section of the two barrel calorimeters at |η| = 0.45 of ATLAS have been exposed to combined beam tests with single electrons and pions. Detailed shower shape studies of electrons and pions with comparisons to various Geant4 based simulations utilizing different physics lists are presented for the endcap beam test. The local hadron calibration approach as used in the full Atlas setup has been applied to the endcap beam test data. An extension of it using layer correlations has been tested with the barrel test beam data. Both methods utilize modular correction steps based on shower shape variables to correct for invisible energy inside the reconstructed clusters in the calorimeters (compensation) and for lost energy deposits outside of the reconstructed clusters (dead material and out-of-cluster deposits). Results for both methods and comparisons to Monte Carlo simulations are presented.

  4. Surface temperature and evapotranspiration: application of local scale methods to regional scales using satellite data

    International Nuclear Information System (INIS)

    Seguin, B.; Courault, D.; Guerif, M.

    1994-01-01

    Remotely sensed surface temperatures have proven useful for monitoring evapotranspiration (ET) rates and crop water use because of their direct relationship with sensible and latent energy exchange processes. Procedures for using the thermal infrared (IR) obtained with hand-held radiometers deployed at ground level are now well established and even routine for many agricultural research and management purposes. The availability of IR from meteorological satellites at scales from 1 km (NOAA-AVHRR) to 5 km (METEOSAT) permits extension of local, ground-based approaches to larger scale crop monitoring programs. Regional observations of surface minus air temperature (i.e., the stress degree day) and remote estimates of daily ET were derived from satellite data over sites in France, the Sahel, and North Africa and summarized here. Results confirm that similar approaches can be applied at local and regional scales despite differences in pixel size and heterogeneity. This article analyzes methods for obtaining these data and outlines the potential utility of satellite data for operational use at the regional scale. (author)

  5. An ensemble method for predicting subnuclear localizations from primary protein structures.

    Directory of Open Access Journals (Sweden)

    Guo Sheng Han

    Full Text Available BACKGROUND: Predicting protein subnuclear localization is a challenging problem. Some previous works based on non-sequence information including Gene Ontology annotations and kernel fusion have respective limitations. The aim of this work is twofold: one is to propose a novel individual feature extraction method; another is to develop an ensemble method to improve prediction performance using comprehensive information represented in the form of high dimensional feature vector obtained by 11 feature extraction methods. METHODOLOGY/PRINCIPAL FINDINGS: A novel two-stage multiclass support vector machine is proposed to predict protein subnuclear localizations. It only considers those feature extraction methods based on amino acid classifications and physicochemical properties. In order to speed up our system, an automatic search method for the kernel parameter is used. The prediction performance of our method is evaluated on four datasets: Lei dataset, multi-localization dataset, SNL9 dataset and a new independent dataset. The overall accuracy of prediction for 6 localizations on Lei dataset is 75.2% and that for 9 localizations on SNL9 dataset is 72.1% in the leave-one-out cross validation, 71.7% for the multi-localization dataset and 69.8% for the new independent dataset, respectively. Comparisons with those existing methods show that our method performs better for both single-localization and multi-localization proteins and achieves more balanced sensitivities and specificities on large-size and small-size subcellular localizations. The overall accuracy improvements are 4.0% and 4.7% for single-localization proteins and 6.5% for multi-localization proteins. The reliability and stability of our classification model are further confirmed by permutation analysis. CONCLUSIONS: It can be concluded that our method is effective and valuable for predicting protein subnuclear localizations. A web server has been designed to implement the proposed method

  6. Simplified approaches to some nonoverlapping domain decomposition methods

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jinchao

    1996-12-31

    An attempt will be made in this talk to present various domain decomposition methods in a way that is intuitively clear and technically coherent and concise. The basic framework used for analysis is the {open_quotes}parallel subspace correction{close_quotes} or {open_quotes}additive Schwarz{close_quotes} method, and other simple technical tools include {open_quotes}local-global{close_quotes} and {open_quotes}global-local{close_quotes} techniques, the formal one is for constructing subspace preconditioner based on a preconditioner on the whole space whereas the later one for constructing preconditioner on the whole space based on a subspace preconditioner. The domain decomposition methods discussed in this talk fall into two major categories: one, based on local Dirichlet problems, is related to the {open_quotes}substructuring method{close_quotes} and the other, based on local Neumann problems, is related to the {open_quotes}Neumann-Neumann method{close_quotes} and {open_quotes}balancing method{close_quotes}. All these methods will be presented in a systematic and coherent manner and the analysis for both two and three dimensional cases are carried out simultaneously. In particular, some intimate relationship between these algorithms are observed and some new variants of the algorithms are obtained.

  7. A local environment approach for deep-level defects in semiconductors: Application to the vacancy in silicon

    International Nuclear Information System (INIS)

    Wang Yongliang; Lindefelt, U.

    1987-04-01

    A local environment approach for calculation of the electronic structure of localized defects in semiconductors is described. The method starts out from a description of localized orbitals or tight-binding model for semiconductors and is based on the recursion method of Haydock. A repeated symmetrical supercell containing 686 atoms plus defects is formed, both the translational and point-group symmetry of the crystal are fully exploited. In this paper, we report an application of this approach to an undistorted isolated vacancy by using a self-consistent Hamiltonian. A bound state of T 2 symmetry at 0.87 eV above the valence-band edge and a number of band resonances within the valence-band were extracted using Lanczos algorithm and a continued-fraction representation of the local density of states. It was found that the T 2 symmetry gap state is mainly p-like and most of the wavefunction for one of the A 1 symmetry resonances is concentrated on the vacant site and another concentrated on the first neighbors of the vacancy. From the small shifts of the band edges of silicon with a vacancy, we can conclude that the supercell is big enough and the interaction between the defects of different supercells is negligible. (author). 37 refs, 12 figs

  8. Parallelised Krylov subspace method for reactor kinetics by IQS approach

    International Nuclear Information System (INIS)

    Gupta, Anurag; Modak, R.S.; Gupta, H.P.; Kumar, Vinod; Bhatt, K.

    2005-01-01

    Nuclear reactor kinetics involves numerical solution of space-time-dependent multi-group neutron diffusion equation. Two distinct approaches exist for this purpose: the direct (implicit time differencing) approach and the improved quasi-static (IQS) approach. Both the approaches need solution of static space-energy-dependent diffusion equations at successive time-steps; the step being relatively smaller for the direct approach. These solutions are usually obtained by Gauss-Seidel type iterative methods. For a faster solution, the Krylov sub-space methods have been tried and also parallelised by many investigators. However, these studies seem to have been done only for the direct approach. In the present paper, parallelised Krylov methods are applied to the IQS approach in addition to the direct approach. It is shown that the speed-up obtained for IQS is higher than that for the direct approach. The reasons for this are also discussed. Thus, the use of IQS approach along with parallelised Krylov solvers seems to be a promising scheme

  9. Local Anesthesia in Cataract Surgery-A Comparison of Different Methods

    Institute of Scientific and Technical Information of China (English)

    Nolan; J; Aziz; M; Ahmad; M; Shehata; M; Iqbal; F

    1993-01-01

    Seven groups of thirty patients undergoing cataract extraction under local anesthesia were each given different combinations of local anesthesia. These varied from a maximum approach using supra-orbital, infra-orbital and facial blocks with Hyalase, orbital compression and pre-operative Acetazolamide down to a minimum group receiving purely an infra- orbital and supra-orbital block with a Ugnocaine/Bupivacaine mixture. There was no significant difference in local analgesia or in the complication rates b...

  10. Development of a localized probabilistic sensitivity method to determine random variable regional importance

    International Nuclear Information System (INIS)

    Millwater, Harry; Singh, Gulshan; Cortina, Miguel

    2012-01-01

    There are many methods to identify the important variable out of a set of random variables, i.e., “inter-variable” importance; however, to date there are no comparable methods to identify the “region” of importance within a random variable, i.e., “intra-variable” importance. Knowledge of the critical region of an input random variable (tail, near-tail, and central region) can provide valuable information towards characterizing, understanding, and improving a model through additional modeling or testing. As a result, an intra-variable probabilistic sensitivity method was developed and demonstrated for independent random variables that computes the partial derivative of a probabilistic response with respect to a localized perturbation in the CDF values of each random variable. These sensitivities are then normalized in absolute value with respect to the largest sensitivity within a distribution to indicate the region of importance. The methodology is implemented using the Score Function kernel-based method such that existing samples can be used to compute sensitivities for negligible cost. Numerical examples demonstrate the accuracy of the method through comparisons with finite difference and numerical integration quadrature estimates. - Highlights: ► Probabilistic sensitivity methodology. ► Determines the “region” of importance within random variables such as left tail, near tail, center, right tail, etc. ► Uses the Score Function approach to reuse the samples, hence, negligible cost. ► No restrictions on the random variable types or limit states.

  11. Hooke–Jeeves Method-used Local Search in a Hybrid Global Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    V. D. Sulimov

    2014-01-01

    Full Text Available Modern methods for optimization investigation of complex systems are based on development and updating the mathematical models of systems because of solving the appropriate inverse problems. Input data desirable for solution are obtained from the analysis of experimentally defined consecutive characteristics for a system or a process. Causal characteristics are the sought ones to which equation coefficients of mathematical models of object, limit conditions, etc. belong. The optimization approach is one of the main ones to solve the inverse problems. In the main case it is necessary to find a global extremum of not everywhere differentiable criterion function. Global optimization methods are widely used in problems of identification and computation diagnosis system as well as in optimal control, computing to-mography, image restoration, teaching the neuron networks, other intelligence technologies. Increasingly complicated systems of optimization observed during last decades lead to more complicated mathematical models, thereby making solution of appropriate extreme problems significantly more difficult. A great deal of practical applications may have the problem con-ditions, which can restrict modeling. As a consequence, in inverse problems the criterion functions can be not everywhere differentiable and noisy. Available noise means that calculat-ing the derivatives is difficult and unreliable. It results in using the optimization methods without calculating the derivatives.An efficiency of deterministic algorithms of global optimization is significantly restrict-ed by their dependence on the extreme problem dimension. When the number of variables is large they use the stochastic global optimization algorithms. As stochastic algorithms yield too expensive solutions, so this drawback restricts their applications. Developing hybrid algo-rithms that combine a stochastic algorithm for scanning the variable space with deterministic local search

  12. Integrating scientific and local knowledge to inform risk-based management approaches for climate adaptation

    Directory of Open Access Journals (Sweden)

    Nathan P. Kettle

    2014-01-01

    Full Text Available Risk-based management approaches to climate adaptation depend on the assessment of potential threats, and their causes, vulnerabilities, and impacts. The refinement of these approaches relies heavily on detailed local knowledge of places and priorities, such as infrastructure, governance structures, and socio-economic conditions, as well as scientific understanding of climate projections and trends. Developing processes that integrate local and scientific knowledge will enhance the value of risk-based management approaches, facilitate group learning and planning processes, and support the capacity of communities to prepare for change. This study uses the Vulnerability, Consequences, and Adaptation Planning Scenarios (VCAPS process, a form of analytic-deliberative dialogue, and the conceptual frameworks of hazard management and climate vulnerability, to integrate scientific and local knowledge. We worked with local government staff in an urbanized barrier island community (Sullivan’s Island, South Carolina to consider climate risks, impacts, and adaptation challenges associated with sea level rise and wastewater and stormwater management. The findings discuss how the process increases understanding of town officials’ views of risks and climate change impacts to barrier islands, the management actions being considered to address of the multiple impacts of concern, and the local tradeoffs and challenges in adaptation planning. We also comment on group learning and specific adaptation tasks, strategies, and needs identified.

  13. Water-sanitation-hygiene mapping: an improved approach for data collection at local level.

    Science.gov (United States)

    Giné-Garriga, Ricard; de Palencia, Alejandro Jiménez-Fernández; Pérez-Foguet, Agustí

    2013-10-01

    Strategic planning and appropriate development and management of water and sanitation services are strongly supported by accurate and accessible data. If adequately exploited, these data might assist water managers with performance monitoring, benchmarking comparisons, policy progress evaluation, resources allocation, and decision making. A variety of tools and techniques are in place to collect such information. However, some methodological weaknesses arise when developing an instrument for routine data collection, particularly at local level: i) comparability problems due to heterogeneity of indicators, ii) poor reliability of collected data, iii) inadequate combination of different information sources, and iv) statistical validity of produced estimates when disaggregated into small geographic subareas. This study proposes an improved approach for water, sanitation and hygiene (WASH) data collection at decentralised level in low income settings, as an attempt to overcome previous shortcomings. The ultimate aim is to provide local policymakers with strong evidences to inform their planning decisions. The survey design takes the Water Point Mapping (WPM) as a starting point to record all available water sources at a particular location. This information is then linked to data produced by a household survey. Different survey instruments are implemented to collect reliable data by employing a variety of techniques, such as structured questionnaires, direct observation and water quality testing. The collected data is finally validated through simple statistical analysis, which in turn produces valuable outputs that might feed into the decision-making process. In order to demonstrate the applicability of the method, outcomes produced from three different case studies (Homa Bay District-Kenya-; Kibondo District-Tanzania-; and Municipality of Manhiça-Mozambique-) are presented. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. User involvement in measuring service quality of local authority occupational therapy services: a new approach.

    NARCIS (Netherlands)

    Sixma, H.J.; Calnan, S.; Calnan, M.; Groenewegen, P.P.

    2001-01-01

    The aim of this paper is two-fold: (i) to describe the development of a new measuring instrument for quality of care from the perspective of the users of local authority Occupational Therapy (OT) services, and (ii) to evaluate the potential of the new instrument as a standardized approach for the

  15. International Students' Motivation and Learning Approach: A Comparison with Local Students

    Science.gov (United States)

    Chue, Kah Loong; Nie, Youyan

    2016-01-01

    Psychological factors contribute to motivation and learning for international students as much as teaching strategies. 254 international students and 144 local students enrolled in a private education institute were surveyed regarding their perception of psychological needs support, their motivation and learning approach. The results from this…

  16. Local cell metrics: a novel method for analysis of cell-cell interactions

    Directory of Open Access Journals (Sweden)

    Chen Chien-Chiang

    2009-10-01

    Full Text Available Abstract Background The regulation of many cell functions is inherently linked to cell-cell contact interactions. However, effects of contact interactions among adherent cells can be difficult to detect with global summary statistics due to the localized nature and noise inherent to cell-cell interactions. The lack of informatics approaches specific for detecting cell-cell interactions is a limitation in the analysis of large sets of cell image data, including traditional and combinatorial or high-throughput studies. Here we introduce a novel histogram-based data analysis strategy, termed local cell metrics (LCMs, which addresses this shortcoming. Results The new LCM method is demonstrated via a study of contact inhibition of proliferation of MC3T3-E1 osteoblasts. We describe how LCMs can be used to quantify the local environment of cells and how LCMs are decomposed mathematically into metrics specific to each cell type in a culture, e.g., differently-labelled cells in fluorescence imaging. Using this approach, a quantitative, probabilistic description of the contact inhibition effects in MC3T3-E1 cultures has been achieved. We also show how LCMs are related to the naïve Bayes model. Namely, LCMs are Bayes class-conditional probability functions, suggesting their use for data mining and classification. Conclusion LCMs are successful in robust detection of cell contact inhibition in situations where conventional global statistics fail to do so. The noise due to the random features of cell behavior was suppressed significantly as a result of the focus on local distances, providing sensitive detection of cell-cell contact effects. The methodology can be extended to any quantifiable feature that can be obtained from imaging of cell cultures or tissue samples, including optical, fluorescent, and confocal microscopy. This approach may prove useful in interpreting culture and histological data in fields where cell-cell interactions play a critical

  17. Simulation of air-heated evaporators using a method of local analysis

    International Nuclear Information System (INIS)

    Parise, J.A.R.; Cartwright, W.G.

    1983-01-01

    The development and application of an analytical method for the performance prediction of air-heated evaporators are presented. A local analysis is employed in which the evaporator is considered as a three dimensional matrix of elementary heat transfer modules. For each element, local film coefficients for both air and the evaporating fluid are determined appropriate to the local conditions, including the two-phase flow regime. An application of the method is considered. (Author) [pt

  18. Developing Methods For Linking Surficial Aquifers With Localized Rainfall Data

    Science.gov (United States)

    Lafrenz, W. B.; van Gaalen, J. F.

    2008-12-01

    Water level hydrographs of the surficial aquifer can be evaluated to identify both the cause and consequence of water supply development. Rainfall, as a source of direct recharge and as a source of delayed or compounded recharge, is often the largest influence on surficial aquifer water level responses. It is clear that proximity of the rain gauge to the observation well is a factor in the degree of correlation, but in central Florida, USA, rainfall patterns change seasonally, with latitude, and with distance from the coast . Thus, for a location in central Florida, correlation of rain events with observed hydrograph responses depends on both distance and direction from an observation well to a rain gauge. In this study, we examine the use of extreme value analysis as a method of selecting the best rainfall data set for describing a given surficial aquifer monitor well. A surficial aquifer monitor well with a substantial suite of data is compared to a series of rainfall data sets from gauges ranging from meters to tens of kilometers in distance from the monitor well. The gauges vary in a wide range of directions from the monitor well in an attempt to identify both a method for rainfall gauge selection to be associated with the monitor well. Each rainfall gauge is described by a correlation coefficient with respect to the surficial aquifer water level data.

  19. Global/local methods research using a common structural analysis framework

    Science.gov (United States)

    Knight, Norman F., Jr.; Ransom, Jonathan B.; Griffin, O. H., Jr.; Thompson, Danniella M.

    1991-01-01

    Methodologies for global/local stress analysis are described including both two- and three-dimensional analysis methods. These methods are being developed within a common structural analysis framework. Representative structural analysis problems are presented to demonstrate the global/local methodologies being developed.

  20. Local Fractional Series Expansion Method for Solving Wave and Diffusion Equations on Cantor Sets

    Directory of Open Access Journals (Sweden)

    Ai-Min Yang

    2013-01-01

    Full Text Available We proposed a local fractional series expansion method to solve the wave and diffusion equations on Cantor sets. Some examples are given to illustrate the efficiency and accuracy of the proposed method to obtain analytical solutions to differential equations within the local fractional derivatives.

  1. Solving Fokker-Planck Equations on Cantor Sets Using Local Fractional Decomposition Method

    Directory of Open Access Journals (Sweden)

    Shao-Hong Yan

    2014-01-01

    Full Text Available The local fractional decomposition method is applied to approximate the solutions for Fokker-Planck equations on Cantor sets with local fractional derivative. The obtained results give the present method that is very effective and simple for solving the differential equations on Cantor set.

  2. Agile Service Development: A Rule-Based Method Engineering Approach

    NARCIS (Netherlands)

    dr. Martijn Zoet; Stijn Hoppenbrouwers; Inge van de Weerd; Johan Versendaal

    2011-01-01

    Agile software development has evolved into an increasingly mature software development approach and has been applied successfully in many software vendors’ development departments. In this position paper, we address the broader agile service development. Based on method engineering principles we

  3. Description of the atomic disorder (local order) in crystals by the mixed-symmetry method

    Science.gov (United States)

    Dudka, A. P.; Novikova, N. E.

    2017-11-01

    An approach to the description of local atomic disorder (short-range order) in single crystals by the mixed-symmetry method based on Bragg scattering data is proposed, and the corresponding software is developed. In defect-containing crystals, each atom in the unit cell can be described by its own symmetry space group. The expression for the calculated structural factor includes summation over different sets of symmetry operations for different atoms. To facilitate the search for new symmetry elements, an "atomic disorder expert" was developed, which estimates the significance of tested models. It is shown that the symmetry lowering for some atoms correlates with the existence of phase transitions (in langasite family crystals) and the anisotropy of physical properties (in rare-earth dodecaborides RB12).

  4. Local and accumulated truncation errors in a class of perturbative numerical methods

    International Nuclear Information System (INIS)

    Adam, G.; Adam, S.; Corciovei, A.

    1980-01-01

    The approach to the solution of the radial Schroedinger equation using piecewise perturbative theory with a step function reference potential leads to a class of powerful numerical methods, conveniently abridged as SF-PNM(K), where K denotes the order at which the perturbation series was truncated. In the present paper rigorous results are given for the local truncation errors and bounds are derived for the accumulated truncated errors associated to SF-PNM(K), K = 0, 1, 2. They allow us to establish the smoothness conditions which have to be fulfilled by the potential in order to ensure a safe use of SF-PNM(K), and to understand the experimentally observed behaviour of the numerical results with the step size h. (author)

  5. A Gaussian mixture copula model based localized Gaussian process regression approach for long-term wind speed prediction

    International Nuclear Information System (INIS)

    Yu, Jie; Chen, Kuilin; Mori, Junichi; Rashid, Mudassir M.

    2013-01-01

    Optimizing wind power generation and controlling the operation of wind turbines to efficiently harness the renewable wind energy is a challenging task due to the intermittency and unpredictable nature of wind speed, which has significant influence on wind power production. A new approach for long-term wind speed forecasting is developed in this study by integrating GMCM (Gaussian mixture copula model) and localized GPR (Gaussian process regression). The time series of wind speed is first classified into multiple non-Gaussian components through the Gaussian mixture copula model and then Bayesian inference strategy is employed to incorporate the various non-Gaussian components using the posterior probabilities. Further, the localized Gaussian process regression models corresponding to different non-Gaussian components are built to characterize the stochastic uncertainty and non-stationary seasonality of the wind speed data. The various localized GPR models are integrated through the posterior probabilities as the weightings so that a global predictive model is developed for the prediction of wind speed. The proposed GMCM–GPR approach is demonstrated using wind speed data from various wind farm locations and compared against the GMCM-based ARIMA (auto-regressive integrated moving average) and SVR (support vector regression) methods. In contrast to GMCM–ARIMA and GMCM–SVR methods, the proposed GMCM–GPR model is able to well characterize the multi-seasonality and uncertainty of wind speed series for accurate long-term prediction. - Highlights: • A novel predictive modeling method is proposed for long-term wind speed forecasting. • Gaussian mixture copula model is estimated to characterize the multi-seasonality. • Localized Gaussian process regression models can deal with the random uncertainty. • Multiple GPR models are integrated through Bayesian inference strategy. • The proposed approach shows higher prediction accuracy and reliability

  6. An integrated lean-methods approach to hospital facilities redesign.

    Science.gov (United States)

    Nicholas, John

    2012-01-01

    Lean production methods for eliminating waste and improving processes in manufacturing are now being applied in healthcare. As the author shows, the methods are appropriate for redesigning hospital facilities. When used in an integrated manner and employing teams of mostly clinicians, the methods produce facility designs that are custom-fit to patient needs and caregiver work processes, and reduce operational costs. The author reviews lean methods and an approach for integrating them in the redesign of hospital facilities. A case example of the redesign of an emergency department shows the feasibility and benefits of the approach.

  7. MEG source localization of spatially extended generators of epileptic activity: comparing entropic and hierarchical bayesian approaches.

    Science.gov (United States)

    Chowdhury, Rasheda Arman; Lina, Jean Marc; Kobayashi, Eliane; Grova, Christophe

    2013-01-01

    Localizing the generators of epileptic activity in the brain using Electro-EncephaloGraphy (EEG) or Magneto-EncephaloGraphy (MEG) signals is of particular interest during the pre-surgical investigation of epilepsy. Epileptic discharges can be detectable from background brain activity, provided they are associated with spatially extended generators. Using realistic simulations of epileptic activity, this study evaluates the ability of distributed source localization methods to accurately estimate the location of the generators and their sensitivity to the spatial extent of such generators when using MEG data. Source localization methods based on two types of realistic models have been investigated: (i) brain activity may be modeled using cortical parcels and (ii) brain activity is assumed to be locally smooth within each parcel. A Data Driven Parcellization (DDP) method was used to segment the cortical surface into non-overlapping parcels and diffusion-based spatial priors were used to model local spatial smoothness within parcels. These models were implemented within the Maximum Entropy on the Mean (MEM) and the Hierarchical Bayesian (HB) source localization frameworks. We proposed new methods in this context and compared them with other standard ones using Monte Carlo simulations of realistic MEG data involving sources of several spatial extents and depths. Detection accuracy of each method was quantified using Receiver Operating Characteristic (ROC) analysis and localization error metrics. Our results showed that methods implemented within the MEM framework were sensitive to all spatial extents of the sources ranging from 3 cm(2) to 30 cm(2), whatever were the number and size of the parcels defining the model. To reach a similar level of accuracy within the HB framework, a model using parcels larger than the size of the sources should be considered.

  8. MEG source localization of spatially extended generators of epileptic activity: comparing entropic and hierarchical bayesian approaches.

    Directory of Open Access Journals (Sweden)

    Rasheda Arman Chowdhury

    Full Text Available Localizing the generators of epileptic activity in the brain using Electro-EncephaloGraphy (EEG or Magneto-EncephaloGraphy (MEG signals is of particular interest during the pre-surgical investigation of epilepsy. Epileptic discharges can be detectable from background brain activity, provided they are associated with spatially extended generators. Using realistic simulations of epileptic activity, this study evaluates the ability of distributed source localization methods to accurately estimate the location of the generators and their sensitivity to the spatial extent of such generators when using MEG data. Source localization methods based on two types of realistic models have been investigated: (i brain activity may be modeled using cortical parcels and (ii brain activity is assumed to be locally smooth within each parcel. A Data Driven Parcellization (DDP method was used to segment the cortical surface into non-overlapping parcels and diffusion-based spatial priors were used to model local spatial smoothness within parcels. These models were implemented within the Maximum Entropy on the Mean (MEM and the Hierarchical Bayesian (HB source localization frameworks. We proposed new methods in this context and compared them with other standard ones using Monte Carlo simulations of realistic MEG data involving sources of several spatial extents and depths. Detection accuracy of each method was quantified using Receiver Operating Characteristic (ROC analysis and localization error metrics. Our results showed that methods implemented within the MEM framework were sensitive to all spatial extents of the sources ranging from 3 cm(2 to 30 cm(2, whatever were the number and size of the parcels defining the model. To reach a similar level of accuracy within the HB framework, a model using parcels larger than the size of the sources should be considered.

  9. Approaches to greenhouse gas accounting methods for biomass carbon

    International Nuclear Information System (INIS)

    Downie, Adriana; Lau, David; Cowie, Annette; Munroe, Paul

    2014-01-01

    This investigation examines different approaches for the GHG flux accounting of activities within a tight boundary of biomass C cycling, with scope limited to exclude all other aspects of the lifecycle. Alternative approaches are examined that a) account for all emissions including biogenic CO 2 cycling – the biogenic method; b) account for the quantity of C that is moved to and maintained in the non-atmospheric pool – the stock method; and c) assume that the net balance of C taken up by biomass is neutral over the short-term and hence there is no requirement to include this C in the calculation – the simplified method. This investigation demonstrates the inaccuracies in both emissions forecasting and abatement calculations that result from the use of the simplified method, which is commonly accepted for use. It has been found that the stock method is the most accurate and appropriate approach for use in calculating GHG inventories, however short-comings of this approach emerge when applied to abatement projects, as it does not account for the increase in biogenic CO 2 emissions that are generated when non-CO 2 GHG emissions in the business-as-usual case are offset. Therefore the biogenic method or a modified version of the stock method should be used to accurately estimate GHG emissions abatement achieved by a project. This investigation uses both the derivation of methodology equations from first principles and worked examples to explore the fundamental differences in the alternative approaches. Examples are developed for three project scenarios including; landfill, combustion and slow-pyrolysis (biochar) of biomass. -- Highlights: • Different approaches can be taken to account for the GHG emissions from biomass. • Simplification of GHG accounting methods is useful, however, can lead to inaccuracies. • Approaches used currently are often inadequate for practises that store carbon. • Accounting methods for emissions forecasting can be inadequate for

  10. BAUM: Improving genome assembly by adaptive unique mapping and local overlap-layout-consensus approach.

    Science.gov (United States)

    Wang, Anqi; Wang, Zhanyu; Li, Zheng; Li, Lei M

    2018-01-15

    It is highly desirable to assemble genomes of high continuity and consistency at low cost. The current bottleneck of draft genome continuity using the Second Generation Sequencing (SGS) reads is primarily caused by uncertainty among repetitive sequences. Even though the Single-Molecule Real-Time sequencing technology is very promising to overcome the uncertainty issue, its relatively high cost and error rate add burden on budget or computation. Many long-read assemblers take the overlap-layout-consensus (OLC) paradigm, which is less sensitive to sequencing errors, heterozygosity and variability of coverage. However, current assemblers of SGS data do not sufficiently take advantage of the OLC approach. Aiming at minimizing uncertainty, the proposed method BAUM, breaks the whole genome into regions by adaptive unique mapping; then the local OLC is used to assemble each region in parallel. BAUM can: (1) perform reference-assisted assembly based on the genome of a close species; (2) or improve the results of existing assemblies that are obtained based on short or long sequencing reads. The tests on two eukaryote genomes, a wild rice Oryza longistaminata and a parrot Melopsittacus undulatus, show that BAUM achieved substantial improvement on genome size and continuity. Besides, BAUM reconstructed a considerable amount of repetitive regions that failed to be assembled by existing short read assemblers. We also propose statistical approaches to control the uncertainty in different steps of BAUM. http://www.zhanyuwang.xin/wordpress/index.php/2017/07/21/baum. lilei@amss.ac.cn. Supplementary data are available at Bioinformatics online. © The Author (2018). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  11. local

    Directory of Open Access Journals (Sweden)

    Abílio Amiguinho

    2005-01-01

    Full Text Available The process of socio-educational territorialisation in rural contexts is the topic of this text. The theme corresponds to a challenge to address it having as main axis of discussion either the problem of social exclusion or that of local development. The reasons to locate the discussion in this last field of analysis are discussed in the first part of the text. Theoretical and political reasons are there articulated because the question is about projects whose intentions and practices call for the political both in the theoretical debate and in the choices that anticipate intervention. From research conducted for several years, I use contributions that aim at discuss and enlighten how school can be a potential locus of local development. Its identification and recognition as local institution (either because of those that work and live in it or because of those that act in the surrounding context are crucial steps to progressively constitute school as a partner for development. The promotion of the local values and roots, the reconstruction of socio-personal and local identities, the production of sociabilities and the equation and solution of shared problems were the dimensions of a socio-educative intervention, markedly globalising. This scenario, as it is argued, was also, intentionally, one of transformation and of deliberate change of school and of the administration of the educative territoires.

  12. Practical approaches for assessing local land use change and conservation priorities in the tropics

    Science.gov (United States)

    Rivas, Cassandra J.

    Tropical areas typically support high biological diversity; however, many are experiencing rapid land-use change. The resulting loss, fragmentation, and degradation of habitats place biodiversity at risk. For these reasons, the tropics are frequently identified as global conservation hotspots. Safeguarding tropical biodiversity necessitates successful and efficient conservation planning and implementation at local scales, where land use decisions are made and enforced. Yet, despite considerable agreement on the need for improved practices, planning may be difficult due to limited resources, such as funding, data, and expertise, especially for small conservation organizations in tropical developing countries. My thesis aims to assist small, non-governmental organizations (NGOs), operating in tropical developing countries, in overcoming resource limitations by providing recommendations for improved conservation planning. Following a brief introduction in Chapter 1, I present a literature review of systematic conservation planning (SCP) projects in the developing tropics. Although SCP is considered an efficient, effective approach, it requires substantial data and expertise to conduct the analysis and may present challenges for implementation. I reviewed and synthesized the methods and results of 14 case studies to identify practical ways to implement and overcome limitations for employing SCP. I found that SCP studies in the peer-reviewed literature were primarily implemented by researchers in large organizations or institutions, as opposed to on-the-ground conservation planners. A variety of data types were used in the SCP analyses, many of which data are freely available. Few case studies involved stakeholders and intended to implement the assessment; instead, the case studies were carried out in the context of research and development, limiting local involvement and implementation. Nonetheless, the studies provided valuable strategies for employing each step of

  13. Linearized versus non-linear inverse methods for seismic localization of underground sources

    DEFF Research Database (Denmark)

    Oh, Geok Lian; Jacobsen, Finn

    2013-01-01

    The problem of localization of underground sources from seismic measurements detected by several geophones located on the ground surface is addressed. Two main approaches to the solution of the problem are considered: a beamforming approach that is derived from the linearized inversion problem, a...

  14. Distributed Power Allocation for Wireless Sensor Network Localization: A Potential Game Approach.

    Science.gov (United States)

    Ke, Mingxing; Li, Ding; Tian, Shiwei; Zhang, Yuli; Tong, Kaixiang; Xu, Yuhua

    2018-05-08

    The problem of distributed power allocation in wireless sensor network (WSN) localization systems is investigated in this paper, using the game theoretic approach. Existing research focuses on the minimization of the localization errors of individual agent nodes over all anchor nodes subject to power budgets. When the service area and the distribution of target nodes are considered, finding the optimal trade-off between localization accuracy and power consumption is a new critical task. To cope with this issue, we propose a power allocation game where each anchor node minimizes the square position error bound (SPEB) of the service area penalized by its individual power. Meanwhile, it is proven that the power allocation game is an exact potential game which has one pure Nash equilibrium (NE) at least. In addition, we also prove the existence of an ϵ -equilibrium point, which is a refinement of NE and the better response dynamic approach can reach the end solution. Analytical and simulation results demonstrate that: (i) when prior distribution information is available, the proposed strategies have better localization accuracy than the uniform strategies; (ii) when prior distribution information is unknown, the performance of the proposed strategies outperforms power management strategies based on the second-order cone program (SOCP) for particular agent nodes after obtaining the estimated distribution of agent nodes. In addition, proposed strategies also provide an instructional trade-off between power consumption and localization accuracy.

  15. Total System Performance Assessment-License Application Methods and Approach

    Energy Technology Data Exchange (ETDEWEB)

    J. McNeish

    2002-09-13

    ''Total System Performance Assessment-License Application (TSPA-LA) Methods and Approach'' provides the top-level method and approach for conducting the TSPA-LA model development and analyses. The method and approach is responsive to the criteria set forth in Total System Performance Assessment Integration (TSPAI) Key Technical Issue (KTI) agreements, the ''Yucca Mountain Review Plan'' (CNWRA 2002 [158449]), and 10 CFR Part 63. This introductory section provides an overview of the TSPA-LA, the projected TSPA-LA documentation structure, and the goals of the document. It also provides a brief discussion of the regulatory framework, the approach to risk management of the development and analysis of the model, and the overall organization of the document. The section closes with some important conventions that are utilized in this document.

  16. Total System Performance Assessment - License Application Methods and Approach

    International Nuclear Information System (INIS)

    McNeish, J.

    2003-01-01

    ''Total System Performance Assessment-License Application (TSPA-LA) Methods and Approach'' provides the top-level method and approach for conducting the TSPA-LA model development and analyses. The method and approach is responsive to the criteria set forth in Total System Performance Assessment Integration (TSPAI) Key Technical Issues (KTIs) identified in agreements with the U.S. Nuclear Regulatory Commission, the ''Yucca Mountain Review Plan'' (YMRP), ''Final Report'' (NRC 2003 [163274]), and the NRC final rule 10 CFR Part 63 (NRC 2002 [156605]). This introductory section provides an overview of the TSPA-LA, the projected TSPA-LA documentation structure, and the goals of the document. It also provides a brief discussion of the regulatory framework, the approach to risk management of the development and analysis of the model, and the overall organization of the document. The section closes with some important conventions that are used in this document

  17. Automated delineation and characterization of drumlins using a localized contour tree approach

    Science.gov (United States)

    Wang, Shujie; Wu, Qiusheng; Ward, Dylan

    2017-10-01

    Drumlins are ubiquitous landforms in previously glaciated regions, formed through a series of complex subglacial processes operating underneath the paleo-ice sheets. Accurate delineation and characterization of drumlins are essential for understanding the formation mechanism of drumlins as well as the flow behaviors and basal conditions of paleo-ice sheets. Automated mapping of drumlins is particularly important for examining the distribution patterns of drumlins across large spatial scales. This paper presents an automated vector-based approach to mapping drumlins from high-resolution light detection and ranging (LiDAR) data. The rationale is to extract a set of concentric contours by building localized contour trees and establishing topological relationships. This automated method can overcome the shortcomings of previously manual and automated methods for mapping drumlins, for instance, the azimuthal biases during the generation of shaded relief images. A case study was carried out over a portion of the New York Drumlin Field. Overall 1181 drumlins were identified from the LiDAR-derived DEM across the study region, which had been underestimated in previous literature. The delineation results were visually and statistically compared to the manual digitization results. The morphology of drumlins was characterized by quantifying the length, width, elongation ratio, height, area, and volume. Statistical and spatial analyses were conducted to examine the distribution pattern and spatial variability of drumlin size and form. The drumlins and the morphologic characteristics exhibit significant spatial clustering rather than randomly distributed patterns. The form of drumlins varies from ovoid to spindle shapes towards the downstream direction of paleo ice flows, along with the decrease in width, area, and volume. This observation is in line with previous studies, which may be explained by the variations in sediment thickness and/or the velocity increases of ice flows

  18. Algebraic Verification Method for SEREs Properties via Groebner Bases Approaches

    Directory of Open Access Journals (Sweden)

    Ning Zhou

    2013-01-01

    Full Text Available This work presents an efficient solution using computer algebra system to perform linear temporal properties verification for synchronous digital systems. The method is essentially based on both Groebner bases approaches and symbolic simulation. A mechanism for constructing canonical polynomial set based symbolic representations for both circuit descriptions and assertions is studied. We then present a complete checking algorithm framework based on these algebraic representations by using Groebner bases. The computational experience result in this work shows that the algebraic approach is a quite competitive checking method and will be a useful supplement to the existent verification methods based on simulation.

  19. Preoperative Computed Tomography-Guided Percutaneous Hookwire Localization of Metallic Marker Clips in the Breast with a Radial Approach: Initial Experience

    Energy Technology Data Exchange (ETDEWEB)

    Uematsu, T.; Kasami, M.; Uchida, Y.; Sanuki, J.; Kimura, K.; Tanaka, K.; Takahashi, K. [Dept. of Diagnostic Radiology, Dept. of Pathology, and Dept. of Breast Surgery, Shizuoka Cancer Center Hospital, Naga-izumi, Shizuoka (Japan)

    2007-07-15

    Background: Hookwire localization is the current standard technique for radiological marking of nonpalpable breast lesions. Stereotactic directional vacuum-assisted breast biopsy (SVAB) is of sufficient sensitivity and specificity to replace surgical biopsy. Wire localization for metallic marker clips placed after SVAB is needed. Purpose: To describe a method for performing computed tomography (CT)-guided hookwire localization using a radial approach for metallic marker clips placed percutaneously after SVAB. Material and Methods: Nineteen women scheduled for SVAB with marker-clip placement, CT-guided wire localization of marker clips, and, eventually, surgical excision were prospectively entered into the study. CT-guided wire localization was performed with a radial approach, followed by placement of a localizing marker-clip surgical excision. Feasibility and reliability of the procedure and the incidence of complications were examined. Results: CT-guided wire localization surgical excision was successfully performed in all 19 women without any complications. The mean total procedure time was 15 min. The median distance on CT image from marker clip to hookwire was 2 mm (range 0-3 mm). Conclusion: CT-guided preoperative hookwire localization with a radial approach for marker clips after SVAB is technically feasible.

  20. A Cross-Layer User Centric Vertical Handover Decision Approach Based on MIH Local Triggers

    Science.gov (United States)

    Rehan, Maaz; Yousaf, Muhammad; Qayyum, Amir; Malik, Shahzad

    Vertical handover decision algorithm that is based on user preferences and coupled with Media Independent Handover (MIH) local triggers have not been explored much in the literature. We have developed a comprehensive cross-layer solution, called Vertical Handover Decision (VHOD) approach, which consists of three parts viz. mechanism for collecting and storing user preferences, Vertical Handover Decision (VHOD) algorithm and the MIH Function (MIHF). MIHF triggers the VHOD algorithm which operates on user preferences to issue handover commands to mobility management protocol. VHOD algorithm is an MIH User and therefore needs to subscribe events and configure thresholds for receiving triggers from MIHF. In this regard, we have performed experiments in WLAN to suggest thresholds for Link Going Down trigger. We have also critically evaluated the handover decision process, proposed Just-in-time interface activation technique, compared our proposed approach with prominent user centric approaches and analyzed our approach from different aspects.

  1. Acoustic Source Localization via Subspace Based Method Using Small Aperture MEMS Arrays

    Directory of Open Access Journals (Sweden)

    Xin Zhang

    2014-01-01

    Full Text Available Small aperture microphone arrays provide many advantages for portable devices and hearing aid equipment. In this paper, a subspace based localization method is proposed for acoustic source using small aperture arrays. The effects of array aperture on localization are analyzed by using array response (array manifold. Besides array aperture, the frequency of acoustic source and the variance of signal power are simulated to demonstrate how to optimize localization performance, which is carried out by introducing frequency error with the proposed method. The proposed method for 5 mm array aperture is validated by simulations and experiments with MEMS microphone arrays. Different types of acoustic sources can be localized with the highest precision of 6 degrees even in the presence of wind noise and other noises. Furthermore, the proposed method reduces the computational complexity compared with other methods.

  2. Chemometric approach to evaluate heavy metals’ content in Daucus Carota from different localities in Serbia

    Directory of Open Access Journals (Sweden)

    Mitic Violeta D.

    2015-01-01

    Full Text Available The aim of this study was to evaluate heavy metal content in carrots (Daucus carota from the different localities in Serbia and assess by the cluster analysis (CA and principal components analysis (PCA the heavy metal contamination of carrots from these areas. Carrot was collected at 13 locations in five districts. Chemometric methods (CA and PCA were applied to classify localities according to heavy metal content in carrots. CA separated localities into two statistical significant clusters. PCA permitted the reduction of 12 variables to four principal components explaining 79.94% of the total variance. The first most important principal component was strongly associated with the value of Cu, Sb, Pb and Tl. This study revealed that CA and PCA appear useful tools for differentiation of localities in different districts using the profile of heavy metal in carrot samples. [Projekat Ministarstva nauke Republike Srbije, br. 172051

  3. An age estimation method using brain local features for T1-weighted images.

    Science.gov (United States)

    Kondo, Chihiro; Ito, Koichi; Kai Wu; Sato, Kazunori; Taki, Yasuyuki; Fukuda, Hiroshi; Aoki, Takafumi

    2015-08-01

    Previous statistical analysis studies using large-scale brain magnetic resonance (MR) image databases have examined that brain tissues have age-related morphological changes. This fact indicates that one can estimate the age of a subject from his/her brain MR image by evaluating morphological changes with healthy aging. This paper proposes an age estimation method using local features extracted from T1-weighted MR images. The brain local features are defined by volumes of brain tissues parcellated into local regions defined by the automated anatomical labeling atlas. The proposed method selects optimal local regions to improve the performance of age estimation. We evaluate performance of the proposed method using 1,146 T1-weighted images from a Japanese MR image database. We also discuss the medical implication of selected optimal local regions.

  4. Anchor-Free Localization Method for Mobile Targets in Coal Mine Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Xiao Xu

    2009-04-01

    Full Text Available Severe natural conditions and complex terrain make it difficult to apply precise localization in underground mines. In this paper, an anchor-free localization method for mobile targets is proposed based on non-metric multi-dimensional scaling (Multi-dimensional Scaling: MDS and rank sequence. Firstly, a coal mine wireless sensor network is constructed in underground mines based on the ZigBee technology. Then a non-metric MDS algorithm is imported to estimate the reference nodes’ location. Finally, an improved sequence-based localization algorithm is presented to complete precise localization for mobile targets. The proposed method is tested through simulations with 100 nodes, outdoor experiments with 15 ZigBee physical nodes, and the experiments in the mine gas explosion laboratory with 12 ZigBee nodes. Experimental results show that our method has better localization accuracy and is more robust in underground mines.

  5. Anchor-free localization method for mobile targets in coal mine wireless sensor networks.

    Science.gov (United States)

    Pei, Zhongmin; Deng, Zhidong; Xu, Shuo; Xu, Xiao

    2009-01-01

    Severe natural conditions and complex terrain make it difficult to apply precise localization in underground mines. In this paper, an anchor-free localization method for mobile targets is proposed based on non-metric multi-dimensional scaling (Multi-dimensional Scaling: MDS) and rank sequence. Firstly, a coal mine wireless sensor network is constructed in underground mines based on the ZigBee technology. Then a non-metric MDS algorithm is imported to estimate the reference nodes' location. Finally, an improved sequence-based localization algorithm is presented to complete precise localization for mobile targets. The proposed method is tested through simulations with 100 nodes, outdoor experiments with 15 ZigBee physical nodes, and the experiments in the mine gas explosion laboratory with 12 ZigBee nodes. Experimental results show that our method has better localization accuracy and is more robust in underground mines.

  6. A Pattern-Oriented Approach to a Methodical Evaluation of Modeling Methods

    Directory of Open Access Journals (Sweden)

    Michael Amberg

    1996-11-01

    Full Text Available The paper describes a pattern-oriented approach to evaluate modeling methods and to compare various methods with each other from a methodical viewpoint. A specific set of principles (the patterns is defined by investigating the notations and the documentation of comparable modeling methods. Each principle helps to examine some parts of the methods from a specific point of view. All principles together lead to an overall picture of the method under examination. First the core ("method neutral" meaning of each principle is described. Then the methods are examined regarding the principle. Afterwards the method specific interpretations are compared with each other and with the core meaning of the principle. By this procedure, the strengths and weaknesses of modeling methods regarding methodical aspects are identified. The principles are described uniformly using a principle description template according to descriptions of object oriented design patterns. The approach is demonstrated by evaluating a business process modeling method.

  7. Bending localization of nitrous oxide under anharmonicity and Fermi coupling: the dynamical potential approach

    International Nuclear Information System (INIS)

    Zhang Chi; Wu Guo-Zhen; Fang Chao

    2010-01-01

    This paper studies the vibrational nonlinear dynamics of nitrous oxide with Fermi coupling between the symmetric stretching and bending coordinates by classical dynamical potential approach. This is a global approach in the sense that the overall dynamics is evidenced by the classical nonlinear variables such as the fixed points and the focus are on a set of levels instead of individual ones. The dynamics of nitrous oxide is demonstrated to be not so much dependent on the excitation energy. Moreover, the localized bending mode is shown to be ubiquitous in all the energy range studied

  8. Contribution to the development of a Local Predictive Approach of the boiling crisis

    International Nuclear Information System (INIS)

    Montout, M.

    2009-01-01

    EDF aims at developing a 'Local Predictive Approach' of the boiling crisis for PWR core configurations, i.e. an approach resulting in (empirical) critical heat flux predictors based on local parameters provided by NEPTUNE-CFD code (for boiling bubbly flows, only in a first stage). Within this general framework, this PhD work consisted in assess one modelling of NEPTUNE-CFD code selected to simulate boiling bubble flows, then improve it. The latter objective led us to focus on the mechanistic modelling of subcooled nucleate boiling in forced convection. After a literature review, we identified physical improvements to be accounted for, especially with respect to bubble sliding phenomenon along the heated wall. Subsequently, we developed a force balance model in order to provide needed closure laws related to bubble detachment diameter from the nucleation site and lift-off bubble diameter from the wall. A new boiling model including such developments was eventually proposed, and preliminary assessed. (author)

  9. Fingerprinting Localization Method Based on TOA and Particle Filtering for Mines

    Directory of Open Access Journals (Sweden)

    Boming Song

    2017-01-01

    Full Text Available Accurate target localization technology plays a very important role in ensuring mine safety production and higher production efficiency. The localization accuracy of a mine localization system is influenced by many factors. The most significant factor is the non-line of sight (NLOS propagation error of the localization signal between the access point (AP and the target node (Tag. In order to improve positioning accuracy, the NLOS error must be suppressed by an optimization algorithm. However, the traditional optimization algorithms are complex and exhibit poor optimization performance. To solve this problem, this paper proposes a new method for mine time of arrival (TOA localization based on the idea of comprehensive optimization. The proposed method utilizes particle filtering to reduce the TOA data error, and the positioning results are further optimized with fingerprinting based on the Manhattan distance. This proposed method combines the advantages of particle filtering and fingerprinting localization. It reduces algorithm complexity and has better error suppression performance. The experimental results demonstrate that, as compared to the symmetric double-sided two-way ranging (SDS-TWR method or received signal strength indication (RSSI based fingerprinting method, the proposed method has a significantly improved localization performance, and the environment adaptability is enhanced.

  10. Approaches and methods for econometric analysis of market power

    DEFF Research Database (Denmark)

    Perekhozhuk, Oleksandr; Glauben, Thomas; Grings, Michael

    2017-01-01

    , functional forms, estimation methods and derived estimates of the degree of market power. Thereafter, we use our framework to evaluate several structural models based on PTA and GIM to measure oligopsony power in the Ukrainian dairy industry. The PTA-based results suggest that the estimated parameters......This study discusses two widely used approaches in the New Empirical Industrial Organization (NEIO) literature and examines the strengths and weaknesses of the Production-Theoretic Approach (PTA) and the General Identification Method (GIM) for the econometric analysis of market power...... in agricultural and food markets. We provide a framework that may help researchers to evaluate and improve structural models of market power. Starting with the specification of the approaches in question, we compare published empirical studies of market power with respect to the choice of the applied approach...

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

    Science.gov (United States)

    2005-05-01

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

  12. Approach for safe visualization and localization of catheters during MR-guided intravascular procedures

    International Nuclear Information System (INIS)

    Weiss, S.; Schaeffter, T.; Brinkert, F.; Kuehne, T.; Buecker, A.

    2003-01-01

    The present paper describes a method for the visualization and localization of a catheter during real-time imaging on a clinical magnetic resonance tomograph (MRT). This method includes the use of an opposite catheter hardware equipped with an optically tunable resonant marker on its tip (OptiMa-Catheter). In the tuned state, the marker produces an intense signal spot in the MR image. The signal is modulated by optical detuning controlled by the MRT system, which results in improved visualization of the catheter tip due to flashing. During real-time imaging, additionally, the localization of the tip is precisely detected and the slice tracking automatically performed. Experiments demonstrate that the OptiMa-Catheter does not generate relevant resonance heating during imaging. Consequently, it combines the visualization and localization known from active techniques with the safety of passive techniques. (orig.) [de

  13. New approach to equipment quality evaluation method with distinct functions

    Directory of Open Access Journals (Sweden)

    Milisavljević Vladimir M.

    2016-01-01

    Full Text Available The paper presents new approach for improving method for quality evaluation and selection of equipment (devices and machinery by applying distinct functions. Quality evaluation and selection of devices and machinery is a multi-criteria problem which involves the consideration of numerous parameters of various origins. Original selection method with distinct functions is based on technical parameters with arbitrary evaluation of each parameter importance (weighting. Improvement of this method, presented in this paper, addresses the issue of weighting of parameters by using Delphi Method. Finally, two case studies are provided, which included quality evaluation of standard boilers for heating and evaluation of load-haul-dump (LHD machines, to demonstrate applicability of this approach. Analytical Hierarchical Process (AHP is used as a control method.

  14. Application of Local Fractional Series Expansion Method to Solve Klein-Gordon Equations on Cantor Sets

    Directory of Open Access Journals (Sweden)

    Ai-Min Yang

    2014-01-01

    Full Text Available We use the local fractional series expansion method to solve the Klein-Gordon equations on Cantor sets within the local fractional derivatives. The analytical solutions within the nondifferential terms are discussed. The obtained results show the simplicity and efficiency of the present technique with application to the problems of the liner differential equations on Cantor sets.

  15. Reduced differential transform method for partial differential equations within local fractional derivative operators

    Directory of Open Access Journals (Sweden)

    Hossein Jafari

    2016-04-01

    Full Text Available The non-differentiable solution of the linear and non-linear partial differential equations on Cantor sets is implemented in this article. The reduced differential transform method is considered in the local fractional operator sense. The four illustrative examples are given to show the efficiency and accuracy features of the presented technique to solve local fractional partial differential equations.

  16. An approach to local diagnostic reference levels (DRL's) in the context of national and international DRL's

    International Nuclear Information System (INIS)

    Rogers, A.T.

    2001-01-01

    In recent years there has been a greater focus on the management of patient doses. This effort has been driven by the realisation of both the increasing magnitude of patient doses and their variation both intra- and inter-nationally. Legislators and guidance-issuing bodies have developed the idea of 'Diagnostic Reference Levels' (DRL's). In particular, the European Union, in their Council Directive 97/43/Euratom, required Member States to develop DRL's. The UK Government, when consolidating this EU Directive into UK legislation, extended the concept of DRL's from a national to an employer level. However, the methodologies used for development of national and international DRL's do not translate to a local level and hence a new approach is required. This paper describes one particular approach made by a UK hospital to introduce 'Local DRL's' in such a manner as to aid the optimisation process. This approach utilises a dose index, based on the local patient population, which is monitored for trends. Any trend in patient dose triggers an investigation linked to the clinical audit system within the Clinical Radiology Department. It is the audit cycle that ensures a continuing move towards an optimised situation. Additional triggers may be employed such as large patient dose variations. (author)

  17. A multiparameter chaos control method based on OGY approach

    International Nuclear Information System (INIS)

    Souza de Paula, Aline; Amorim Savi, Marcelo

    2009-01-01

    Chaos control is based on the richness of responses of chaotic behavior and may be understood as the use of tiny perturbations for the stabilization of a UPO embedded in a chaotic attractor. Since one of these UPO can provide better performance than others in a particular situation the use of chaos control can make this kind of behavior to be desirable in a variety of applications. The OGY method is a discrete technique that considers small perturbations promoted in the neighborhood of the desired orbit when the trajectory crosses a specific surface, such as a Poincare section. This contribution proposes a multiparameter semi-continuous method based on OGY approach in order to control chaotic behavior. Two different approaches are possible with this method: coupled approach, where all control parameters influences system dynamics although they are not active; and uncoupled approach that is a particular case where control parameters return to the reference value when they become passive parameters. As an application of the general formulation, it is investigated a two-parameter actuation of a nonlinear pendulum control employing coupled and uncoupled approaches. Analyses are carried out considering signals that are generated by numerical integration of the mathematical model using experimentally identified parameters. Results show that the procedure can be a good alternative for chaos control since it provides a more effective UPO stabilization than the classical single-parameter approach.

  18. A composite experimental dynamic substructuring method based on partitioned algorithms and localized Lagrange multipliers

    Science.gov (United States)

    Abbiati, Giuseppe; La Salandra, Vincenzo; Bursi, Oreste S.; Caracoglia, Luca

    2018-02-01

    Successful online hybrid (numerical/physical) dynamic substructuring simulations have shown their potential in enabling realistic dynamic analysis of almost any type of non-linear structural system (e.g., an as-built/isolated viaduct, a petrochemical piping system subjected to non-stationary seismic loading, etc.). Moreover, owing to faster and more accurate testing equipment, a number of different offline experimental substructuring methods, operating both in time (e.g. the impulse-based substructuring) and frequency domains (i.e. the Lagrange multiplier frequency-based substructuring), have been employed in mechanical engineering to examine dynamic substructure coupling. Numerous studies have dealt with the above-mentioned methods and with consequent uncertainty propagation issues, either associated with experimental errors or modelling assumptions. Nonetheless, a limited number of publications have systematically cross-examined the performance of the various Experimental Dynamic Substructuring (EDS) methods and the possibility of their exploitation in a complementary way to expedite a hybrid experiment/numerical simulation. From this perspective, this paper performs a comparative uncertainty propagation analysis of three EDS algorithms for coupling physical and numerical subdomains with a dual assembly approach based on localized Lagrange multipliers. The main results and comparisons are based on a series of Monte Carlo simulations carried out on a five-DoF linear/non-linear chain-like systems that include typical aleatoric uncertainties emerging from measurement errors and excitation loads. In addition, we propose a new Composite-EDS (C-EDS) method to fuse both online and offline algorithms into a unique simulator. Capitalizing from the results of a more complex case study composed of a coupled isolated tank-piping system, we provide a feasible way to employ the C-EDS method when nonlinearities and multi-point constraints are present in the emulated system.

  19. Exact method for numerically analyzing a model of local denaturation in superhelically stressed DNA

    International Nuclear Information System (INIS)

    Fye, R.M.; Benham, C.J.

    1999-01-01

    Local denaturation, the separation at specific sites of the two strands comprising the DNA double helix, is one of the most fundamental processes in biology, required to allow the base sequence to be read both in DNA transcription and in replication. In living organisms this process can be mediated by enzymes which regulate the amount of superhelical stress imposed on the DNA. We present a numerically exact technique for analyzing a model of denaturation in superhelically stressed DNA. This approach is capable of predicting the locations and extents of transition in circular superhelical DNA molecules of kilobase lengths and specified base pair sequences. It can also be used for closed loops of DNA which are typically found in vivo to be kilobases long. The analytic method consists of an integration over the DNA twist degrees of freedom followed by the introduction of auxiliary variables to decouple the remaining degrees of freedom, which allows the use of the transfer matrix method. The algorithm implementing our technique requires O(N 2 ) operations and O(N) memory to analyze a DNA domain containing N base pairs. However, to analyze kilobase length DNA molecules it must be implemented in high precision floating point arithmetic. An accelerated algorithm is constructed by imposing an upper bound M on the number of base pairs that can simultaneously denature in a state. This accelerated algorithm requires O(MN) operations, and has an analytically bounded error. Sample calculations show that it achieves high accuracy (greater than 15 decimal digits) with relatively small values of M (M<0.05N) for kilobase length molecules under physiologically relevant conditions. Calculations are performed on the superhelical pBR322 DNA sequence to test the accuracy of the method. With no free parameters in the model, the locations and extents of local denaturation predicted by this analysis are in quantitatively precise agreement with in vitro experimental measurements

  20. Fatigue life evaluation of 42CrMo4 nitrided steel by local approach: Equivalent strain-life-time

    International Nuclear Information System (INIS)

    Terres, Mohamed Ali; Sidhom, Habib

    2012-01-01

    Highlights: → Ion nitriding treatment of 42CrMo4 steel improves their fatigue strength by 32% as compared with the untreated state. → This improvement is the result of the beneficial effects of the superficial work- hardening and of the stabilized compressive residual stress. → The notch region is found to be the fatigue crack nucleation site resulting from a stress concentration (Kt = 1.6). → The local equivalent strain-fatigue life method was found to be an interesting predictive fatigue life method for nitrided parts. -- Abstract: In this paper, the fatigue resistance of 42CrMo4 steel in his untreated and nitrided state was evaluated, using both experimental and numerical approaches. The experimental assessment was conducted using three points fatigue flexion tests on notched specimens at R = 0.1. Microstructure analysis, micro-Vickers hardness test, and scanning electron microscope observation were carried out for evaluating experiments. In results, the fatigue cracks of nitrided specimens were initiated at the surface. The fatigue life of nitrided specimens was prolonged compared to that of the untreated. The numerical method used in this study to predict the nucleation fatigue life was developed on the basis of a local approach, which took into account the applied stresses and stabilized residual stresses during the cyclic loading and the low cyclic fatigue characteristics. The propagation fatigue life was calculated using fracture mechanics concepts. It was found that the numerical results were well correlated with the experimental ones.

  1. The regional approach and regional studies method in the process of geography teaching

    Science.gov (United States)

    Dermendzhieva, Stela; Doikov, Martin

    2017-03-01

    We define the regional approach as a manner of relations among the global trends of development of the "Society-man-nature" system and the local differentiating level of knowledge. Conditionally, interactions interlace under the influence of the character of Geography as a science, education, approaches, goals and teaching methods. Global, national and local development differentiates in three concentric circles at the level of knowledge. It is determined as a conception of modern, complex and effective mechanism for young people, through which knowledge develops in regional historical and cultural perspective; self-consciousness for socio-economic and cultural integration is formed as a part of the. historical-geographical image of the native land. This way an attitude to the. native land is formed as a connecting construct between patriotism to the motherland and the same in global aspect. The possibility for integration and cooperation of the educative geographical content with all the local historical-geographical, regional, profession orientating, artistic, municipal and district institutions, is outlined. Contemporary geographical education appears to be a powerful and indispensable mechanism for organization of human sciences, while the regional approach and the application of the regional studies method stimulate and motivate the development and realization of optimal capacities for direct connection with the local structures and environments.

  2. Iterative observer based method for source localization problem for Poisson equation in 3D

    KAUST Repository

    Majeed, Muhammad Usman; Laleg-Kirati, Taous-Meriem

    2017-01-01

    A state-observer based method is developed to solve point source localization problem for Poisson equation in a 3D rectangular prism with available boundary data. The technique requires a weighted sum of solutions of multiple boundary data

  3. RESEARCH ON FEATURE POINTS EXTRACTION METHOD FOR BINARY MULTISCALE AND ROTATION INVARIANT LOCAL FEATURE DESCRIPTOR

    Directory of Open Access Journals (Sweden)

    Hongwei Ying

    2014-08-01

    Full Text Available An extreme point of scale space extraction method for binary multiscale and rotation invariant local feature descriptor is studied in this paper in order to obtain a robust and fast method for local image feature descriptor. Classic local feature description algorithms often select neighborhood information of feature points which are extremes of image scale space, obtained by constructing the image pyramid using certain signal transform method. But build the image pyramid always consumes a large amount of computing and storage resources, is not conducive to the actual applications development. This paper presents a dual multiscale FAST algorithm, it does not need to build the image pyramid, but can extract feature points of scale extreme quickly. Feature points extracted by proposed method have the characteristic of multiscale and rotation Invariant and are fit to construct the local feature descriptor.

  4. A meshless local radial basis function method for two-dimensional incompressible Navier-Stokes equations

    KAUST Repository

    Wang, Zhiheng; Huang, Zhu; Zhang, Wei; Xi, Guang

    2014-01-01

    main advantages of the method. One is that the unstructured nodes generation in the computational domain is quite simple, without much concern about the mesh quality; the other is that the localization of the obtained collocations for the discretization

  5. Network approach for local and community governance of energy: The case of Oxfordshire

    International Nuclear Information System (INIS)

    Parag, Yael; Hamilton, Jo; White, Vicki; Hogan, Bernie

    2013-01-01

    One of the many barriers to the incorporation of local and community actors in emerging energy governance structures and policy delivery mechanisms is the lack of thorough understanding of how they work in practice, and how best to support and develop effective local energy governance. Taking a meso-level perspective and a network approach to governance, this paper sheds some new light on this issue, by focusing on the relation, channels of communication and interactions between low carbon community groups (LCCGs) and other actors. Based on data gathered from LCCGs in Oxfordshire, UK, via network survey and interviews the research maps the relations in terms of the exchanges of information and financial support, and presents a relation-based structure of local energy governance. Analysis reveals the intensity of energy related information exchanges that is taking place at the county level and highlights the centrality of intermediary organization in facilitating information flow. The analysis also identifies actors that are not very dominant in their amount of exchanges, but fill ‘weak-tie’ functions between otherwise disconnected LCCGs or other actors in the network. As an analytical tool the analysis could be useful for various state and non-state actors that want to better understand and support – financially and otherwise – actors that enable energy related local action. - Highlights: • We used social network analysis to examine local and community governance of energy. • We examined information and financial support flow within the network. • Analysis highlights central and peripheral actors in the local governance structure. • The findings highlight the central role intermediary organizations have in local governance structures

  6. Spatially adaptive hp refinement approach for PN neutron transport equation using spectral element method

    International Nuclear Information System (INIS)

    Nahavandi, N.; Minuchehr, A.; Zolfaghari, A.; Abbasi, M.

    2015-01-01

    Highlights: • Powerful hp-SEM refinement approach for P N neutron transport equation has been presented. • The method provides great geometrical flexibility and lower computational cost. • There is a capability of using arbitrary high order and non uniform meshes. • Both posteriori and priori local error estimation approaches have been employed. • High accurate results are compared against other common adaptive and uniform grids. - Abstract: In this work we presented the adaptive hp-SEM approach which is obtained from the incorporation of Spectral Element Method (SEM) and adaptive hp refinement. The SEM nodal discretization and hp adaptive grid-refinement for even-parity Boltzmann neutron transport equation creates powerful grid refinement approach with high accuracy solutions. In this regard a computer code has been developed to solve multi-group neutron transport equation in one-dimensional geometry using even-parity transport theory. The spatial dependence of flux has been developed via SEM method with Lobatto orthogonal polynomial. Two commonly error estimation approaches, the posteriori and the priori has been implemented. The incorporation of SEM nodal discretization method and adaptive hp grid refinement leads to high accurate solutions. Coarser meshes efficiency and significant reduction of computer program runtime in comparison with other common refining methods and uniform meshing approaches is tested along several well-known transport benchmarks

  7. Damage detection of rotating wind turbine blades using local flexibility method and long-gauge fiber Bragg grating sensors

    Science.gov (United States)

    Hsu, Ting-Yu; Shiao, Shen-Yuan; Liao, Wen-I.

    2018-01-01

    Wind turbines are a cost-effective alternative energy source; however, their blades are susceptible to damage. Therefore, damage detection of wind turbine blades is of great importance for condition monitoring of wind turbines. Many vibration-based structural damage detection techniques have been proposed in the last two decades. The local flexibility method, which can determine local stiffness variations of beam-like structures by using measured modal parameters, is one of the most promising vibration-based approaches. The local flexibility method does not require a finite element model of the structure. A few structural modal parameters identified from the ambient vibration signals both before and after damage are required for this method. In this study, we propose a damage detection approach for rotating wind turbine blades using the local flexibility method based on the dynamic macro-strain signals measured by long-gauge fiber Bragg grating (FBG)-based sensors. A small wind turbine structure was constructed and excited using a shaking table to generate vibration signals. The structure was designed to have natural frequencies as close as possible to those of a typical 1.5 MW wind turbine in real scale. The optical fiber signal of the rotating blades was transmitted to the data acquisition system through a rotary joint fixed inside the hollow shaft of the wind turbine. Reversible damage was simulated by aluminum plates attached to some sections of the wind turbine blades. The damaged locations of the rotating blades were successfully detected using the proposed approach, with the extent of damage somewhat over-estimated. Nevertheless, although the specimen of wind turbine blades cannot represent a real one, the results still manifest that FBG-based macro-strain measurement has potential to be employed to obtain the modal parameters of the rotating wind turbines and then locations of wind turbine segments with a change of rigidity can be estimated effectively by

  8. Local Likelihood Approach for High-Dimensional Peaks-Over-Threshold Inference

    KAUST Repository

    Baki, Zhuldyzay

    2018-05-14

    Global warming is affecting the Earth climate year by year, the biggest difference being observable in increasing temperatures in the World Ocean. Following the long- term global ocean warming trend, average sea surface temperatures across the global tropics and subtropics have increased by 0.4–1◦C in the last 40 years. These rates become even higher in semi-enclosed southern seas, such as the Red Sea, threaten- ing the survival of thermal-sensitive species. As average sea surface temperatures are projected to continue to rise, careful study of future developments of extreme temper- atures is paramount for the sustainability of marine ecosystem and biodiversity. In this thesis, we use Extreme-Value Theory to study sea surface temperature extremes from a gridded dataset comprising 16703 locations over the Red Sea. The data were provided by Operational SST and Sea Ice Analysis (OSTIA), a satellite-based data system designed for numerical weather prediction. After pre-processing the data to account for seasonality and global trends, we analyze the marginal distribution of ex- tremes, defined as observations exceeding a high spatially varying threshold, using the Generalized Pareto distribution. This model allows us to extrapolate beyond the ob- served data to compute the 100-year return levels over the entire Red Sea, confirming the increasing trend of extreme temperatures. To understand the dynamics govern- ing the dependence of extreme temperatures in the Red Sea, we propose a flexible local approach based on R-Pareto processes, which extend the univariate Generalized Pareto distribution to the spatial setting. Assuming that the sea surface temperature varies smoothly over space, we perform inference based on the gradient score method over small regional neighborhoods, in which the data are assumed to be stationary in space. This approach allows us to capture spatial non-stationarity, and to reduce the overall computational cost by taking advantage of

  9. A Toolkit Modeling Approach for Sustainable Forest Management Planning: Achieving Balance between Science and Local Needs

    Directory of Open Access Journals (Sweden)

    Brian R. Sturtevant

    2007-12-01

    Full Text Available To assist forest managers in balancing an increasing diversity of resource objectives, we developed a toolkit modeling approach for sustainable forest management (SFM. The approach inserts a meta-modeling strategy into a collaborative modeling framework grounded in adaptive management philosophy that facilitates participation among stakeholders, decision makers, and local domain experts in the meta-model building process. The modeling team works iteratively with each of these groups to define essential questions, identify data resources, and then determine whether available tools can be applied or adapted, or whether new tools can be rapidly created to fit the need. The desired goal of the process is a linked series of domain-specific models (tools that balances generalized "top-down" models (i.e., scientific models developed without input from the local system with case-specific customized "bottom-up" models that are driven primarily by local needs. Information flow between models is organized according to vertical (i.e., between scale and horizontal (i.e., within scale dimensions. We illustrate our approach within a 2.1 million hectare forest planning district in central Labrador, a forested landscape where social and ecological values receive a higher priority than economic values. However, the focus of this paper is on the process of how SFM modeling tools and concepts can be rapidly assembled and applied in new locations, balancing efficient transfer of science with adaptation to local needs. We use the Labrador case study to illustrate strengths and challenges uniquely associated with a meta-modeling approach to integrated modeling as it fits within the broader collaborative modeling framework. Principle advantages of the approach include the scientific rigor introduced by peer-reviewed models, combined with the adaptability of meta-modeling. A key challenge is the limited transparency of scientific models to different participatory groups

  10. Localization Framework for Real-Time UAV Autonomous Landing: An On-Ground Deployed Visual Approach.

    Science.gov (United States)

    Kong, Weiwei; Hu, Tianjiang; Zhang, Daibing; Shen, Lincheng; Zhang, Jianwei

    2017-06-19

    [-5]One of the greatest challenges for fixed-wing unmanned aircraft vehicles (UAVs) is safe landing. Hereafter, an on-ground deployed visual approach is developed in this paper. This approach is definitely suitable for landing within the global navigation satellite system (GNSS)-denied environments. As for applications, the deployed guidance system makes full use of the ground computing resource and feedbacks the aircraft's real-time localization to its on-board autopilot. Under such circumstances, a separate long baseline stereo architecture is proposed to possess an extendable baseline and wide-angle field of view (FOV) against the traditional fixed baseline schemes. Furthermore, accuracy evaluation of the new type of architecture is conducted by theoretical modeling and computational analysis. Dataset-driven experimental results demonstrate the feasibility and effectiveness of the developed approach.

  11. Localization Framework for Real-Time UAV Autonomous Landing: An On-Ground Deployed Visual Approach

    Directory of Open Access Journals (Sweden)

    Weiwei Kong

    2017-06-01

    Full Text Available [-5]One of the greatest challenges for fixed-wing unmanned aircraft vehicles (UAVs is safe landing. Hereafter, an on-ground deployed visual approach is developed in this paper. This approach is definitely suitable for landing within the global navigation satellite system (GNSS-denied environments. As for applications, the deployed guidance system makes full use of the ground computing resource and feedbacks the aircraft’s real-time localization to its on-board autopilot. Under such circumstances, a separate long baseline stereo architecture is proposed to possess an extendable baseline and wide-angle field of view (FOV against the traditional fixed baseline schemes. Furthermore, accuracy evaluation of the new type of architecture is conducted by theoretical modeling and computational analysis. Dataset-driven experimental results demonstrate the feasibility and effectiveness of the developed approach.

  12. Peak Detection Method Evaluation for Ion Mobility Spectrometry by Using Machine Learning Approaches

    DEFF Research Database (Denmark)

    Hauschild, Anne-Christin; Kopczynski, Dominik; D'Addario, Marianna

    2013-01-01

    machine learning methods exist, an inevitable preprocessing step is reliable and robust peak detection without manual intervention. In this work we evaluate four state-of-the-art approaches for automated IMS-based peak detection: local maxima search, watershed transformation with IPHEx, region......-merging with VisualNow, and peak model estimation (PME).We manually generated Metabolites 2013, 3 278 a gold standard with the aid of a domain expert (manual) and compare the performance of the four peak calling methods with respect to two distinct criteria. We first utilize established machine learning methods...

  13. DactyLoc : A minimally geo-referenced WiFi+GSM-fingerprint-based localization method for positioning in urban spaces

    DEFF Research Database (Denmark)

    Cujia, Kristian; Wirz, Martin; Kjærgaard, Mikkel Baun

    2012-01-01

    Fingerprinting-based localization methods relying on WiFi and GSM information provide sufficient localization accuracy for many mobile phone applications. Most of the existing approaches require a training set consisting of geo-referenced fingerprints to build a reference database. We propose...... a collaborative, semi-supervised WiFi+GSM fingerprinting method where only a small fraction of all fingerprints needs to be geo-referenced. Our approach enables indexing of areas in the absence of GPS reception as often found in urban spaces and indoors without manual labeling of fingerprints. The method takes...

  14. 3D spatially-adaptive canonical correlation analysis: Local and global methods.

    Science.gov (United States)

    Yang, Zhengshi; Zhuang, Xiaowei; Sreenivasan, Karthik; Mishra, Virendra; Curran, Tim; Byrd, Richard; Nandy, Rajesh; Cordes, Dietmar

    2018-04-01

    Local spatially-adaptive canonical correlation analysis (local CCA) with spatial constraints has been introduced to fMRI multivariate analysis for improved modeling of activation patterns. However, current algorithms require complicated spatial constraints that have only been applied to 2D local neighborhoods because the computational time would be exponentially increased if the same method is applied to 3D spatial neighborhoods. In this study, an efficient and accurate line search sequential quadratic programming (SQP) algorithm has been developed to efficiently solve the 3D local CCA problem with spatial constraints. In addition, a spatially-adaptive kernel CCA (KCCA) method is proposed to increase accuracy of fMRI activation maps. With oriented 3D spatial filters anisotropic shapes can be estimated during the KCCA analysis of fMRI time courses. These filters are orientation-adaptive leading to rotational invariance to better match arbitrary oriented fMRI activation patterns, resulting in improved sensitivity of activation detection while significantly reducing spatial blurring artifacts. The kernel method in its basic form does not require any spatial constraints and analyzes the whole-brain fMRI time series to construct an activation map. Finally, we have developed a penalized kernel CCA model that involves spatial low-pass filter constraints to increase the specificity of the method. The kernel CCA methods are compared with the standard univariate method and with two different local CCA methods that were solved by the SQP algorithm. Results show that SQP is the most efficient algorithm to solve the local constrained CCA problem, and the proposed kernel CCA methods outperformed univariate and local CCA methods in detecting activations for both simulated and real fMRI episodic memory data. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. A Novel Feature-Level Data Fusion Method for Indoor Autonomous Localization

    Directory of Open Access Journals (Sweden)

    Minxiang Liu

    2013-01-01

    Full Text Available We present a novel feature-level data fusion method for autonomous localization in an inactive multiple reference unknown indoor environment. Since monocular sensors cannot provide the depth information directly, the proposed method incorporates the edge information of images from a camera with homologous depth information received from an infrared sensor. Real-time experimental results demonstrate that the accuracies of position and orientation are greatly improved by using the proposed fusion method in an unknown complex indoor environment. Compared to monocular localization, the proposed method is found to have up to 70 percent improvement in accuracy.

  16. GRAM-CNN: a deep learning approach with local context for named entity recognition in biomedical text.

    Science.gov (United States)

    Zhu, Qile; Li, Xiaolin; Conesa, Ana; Pereira, Cécile

    2018-05-01

    Best performing named entity recognition (NER) methods for biomedical literature are based on hand-crafted features or task-specific rules, which are costly to produce and difficult to generalize to other corpora. End-to-end neural networks achieve state-of-the-art performance without hand-crafted features and task-specific knowledge in non-biomedical NER tasks. However, in the biomedical domain, using the same architecture does not yield competitive performance compared with conventional machine learning models. We propose a novel end-to-end deep learning approach for biomedical NER tasks that leverages the local contexts based on n-gram character and word embeddings via Convolutional Neural Network (CNN). We call this approach GRAM-CNN. To automatically label a word, this method uses the local information around a word. Therefore, the GRAM-CNN method does not require any specific knowledge or feature engineering and can be theoretically applied to a wide range of existing NER problems. The GRAM-CNN approach was evaluated on three well-known biomedical datasets containing different BioNER entities. It obtained an F1-score of 87.26% on the Biocreative II dataset, 87.26% on the NCBI dataset and 72.57% on the JNLPBA dataset. Those results put GRAM-CNN in the lead of the biological NER methods. To the best of our knowledge, we are the first to apply CNN based structures to BioNER problems. The GRAM-CNN source code, datasets and pre-trained model are available online at: https://github.com/valdersoul/GRAM-CNN. andyli@ece.ufl.edu or aconesa@ufl.edu. Supplementary data are available at Bioinformatics online.

  17. Preoperative computed tomography-guided percutaneous hookwire localization of metallic marker clips in the breast with a radial approach: initial experience.

    Science.gov (United States)

    Uematsu, T; Kasami, M; Uchida, Y; Sanuki, J; Kimura, K; Tanaka, K; Takahashi, K

    2007-06-01

    Hookwire localization is the current standard technique for radiological marking of nonpalpable breast lesions. Stereotactic directional vacuum-assisted breast biopsy (SVAB) is of sufficient sensitivity and specificity to replace surgical biopsy. Wire localization for metallic marker clips placed after SVAB is needed. To describe a method for performing computed tomography (CT)-guided hookwire localization using a radial approach for metallic marker clips placed percutaneously after SVAB. Nineteen women scheduled for SVAB with marker-clip placement, CT-guided wire localization of marker clips, and, eventually, surgical excision were prospectively entered into the study. CT-guided wire localization was performed with a radial approach, followed by placement of a localizing marker-clip surgical excision. Feasibility and reliability of the procedure and the incidence of complications were examined. CT-guided wire localization surgical excision was successfully performed in all 19 women without any complications. The mean total procedure time was 15 min. The median distance on CT image from marker clip to hookwire was 2 mm (range 0-3 mm). CT-guided preoperative hookwire localization with a radial approach for marker clips after SVAB is technically feasible.

  18. A hybrid approach for efficient anomaly detection using metaheuristic methods

    Directory of Open Access Journals (Sweden)

    Tamer F. Ghanem

    2015-07-01

    Full Text Available Network intrusion detection based on anomaly detection techniques has a significant role in protecting networks and systems against harmful activities. Different metaheuristic techniques have been used for anomaly detector generation. Yet, reported literature has not studied the use of the multi-start metaheuristic method for detector generation. This paper proposes a hybrid approach for anomaly detection in large scale datasets using detectors generated based on multi-start metaheuristic method and genetic algorithms. The proposed approach has taken some inspiration of negative selection-based detector generation. The evaluation of this approach is performed using NSL-KDD dataset which is a modified version of the widely used KDD CUP 99 dataset. The results show its effectiveness in generating a suitable number of detectors with an accuracy of 96.1% compared to other competitors of machine learning algorithms.

  19. High-precision approach to localization scheme of visible light communication based on artificial neural networks and modified genetic algorithms

    Science.gov (United States)

    Guan, Weipeng; Wu, Yuxiang; Xie, Canyu; Chen, Hao; Cai, Ye; Chen, Yingcong

    2017-10-01

    An indoor positioning algorithm based on visible light communication (VLC) is presented. This algorithm is used to calculate a three-dimensional (3-D) coordinate of an indoor optical wireless environment, which includes sufficient orders of multipath reflections from reflecting surfaces of the room. Leveraging the global optimization ability of the genetic algorithm (GA), an innovative framework for 3-D position estimation based on a modified genetic algorithm is proposed. Unlike other techniques using VLC for positioning, the proposed system can achieve indoor 3-D localization without making assumptions about the height or acquiring the orientation angle of the mobile terminal. Simulation results show that an average localization error of less than 1.02 cm can be achieved. In addition, in most VLC-positioning systems, the effect of reflection is always neglected and its performance is limited by reflection, which makes the results not so accurate for a real scenario and the positioning errors at the corners are relatively larger than other places. So, we take the first-order reflection into consideration and use artificial neural network to match the model of a nonlinear channel. The studies show that under the nonlinear matching of direct and reflected channels the average positioning errors of four corners decrease from 11.94 to 0.95 cm. The employed algorithm is emerged as an effective and practical method for indoor localization and outperform other existing indoor wireless localization approaches.

  20. Systematic approaches to data analysis from the Critical Decision Method

    Directory of Open Access Journals (Sweden)

    Martin Sedlár

    2015-01-01

    Full Text Available The aim of the present paper is to introduce how to analyse the qualitative data from the Critical Decision Method. At first, characterizing the method provides the meaningful introduction into the issue. This method used in naturalistic decision making research is one of the cognitive task analysis methods, it is based on the retrospective semistructured interview about critical incident from the work and it may be applied in various domains such as emergency services, military, transport, sport or industry. Researchers can make two types of methodological adaptation. Within-method adaptations modify the way of conducting the interviews and cross-method adaptations combine this method with other related methods. There are many decsriptions of conducting the interview, but the descriptions how the data should be analysed are rare. Some researchers use conventional approaches like content analysis, grounded theory or individual procedures with reference to the objectives of research project. Wong (2004 describes two approaches to data analysis proposed for this method of data collection, which are described and reviewed in the details. They enable systematic work with a large amount of data. The structured approach organizes the data according to an a priori analysis framework and it is suitable for clearly defined object of research. Each incident is studied separately. At first, the decision chart showing the main decision points and then the incident summary are made. These decision points are used to identify the relevant statements from the transcript, which are analysed in terms of the Recognition-Primed Decision Model. Finally, the results from all the analysed incidents are integrated. The limitation of the structured approach is it may not reveal some interesting concepts. The emergent themes approach helps to identify these concepts while maintaining a systematic framework for analysis and it is used for exploratory research design. It

  1. Experiential Approach to Teaching Statistics and Research Methods ...

    African Journals Online (AJOL)

    Statistics and research methods are among the more demanding topics for students of education to master at both the undergraduate and postgraduate levels. It is our conviction that teaching these topics should be combined with real practical experiences. We discuss an experiential teaching/ learning approach that ...

  2. Book Review: Comparative Education Research: Approaches and Methods

    Directory of Open Access Journals (Sweden)

    Noel Mcginn

    2014-10-01

    Full Text Available Book Review Comparative Education Research: Approaches and Methods (2nd edition By Mark Bray, Bob Adamson and Mark Mason (Eds. (2014, 453p ISBN: 978-988-17852-8-2, Hong Kong: Comparative Education Research Centre and Springer

  3. A sequential mixed methods research approach to investigating HIV ...

    African Journals Online (AJOL)

    Sequential mixed methods research is an effective approach for investigating complex problems, but it has not been extensively used in construction management research. In South Africa, the HIV/AIDS pandemic has seen construction management taking on a vital responsibility since the government called upon the ...

  4. Teaching Psychological Research Methods through a Pragmatic and Programmatic Approach

    Science.gov (United States)

    Rosenkranz, Patrick; Fielden, Amy; Tzemou, Effy

    2014-01-01

    Research methods teaching in psychology is pivotal in preparing students for the transition from student as learner to independent practitioner. We took an action research approach to re-design, implement and evaluate a module guiding students through a programmatic and pragmatic research cycle. These revisions allow students to experience how…

  5. The Feldenkrais Method: A Dynamic Approach to Changing Motor Behavior.

    Science.gov (United States)

    Buchanan, Patricia A.; Ulrich, Beverly D.

    2001-01-01

    Describes the Feldenkrais Method of somatic education, noting parallels with a dynamic systems theory (DST) approach to motor behavior. Feldenkrais uses movement and perception to foster individualized improvement in function. DST explains that a human-environment system continually adapts to changing conditions and assembles behaviors…

  6. Mapping Patterns of Local Recurrence After Pancreaticoduodenectomy for Pancreatic Adenocarcinoma: A New Approach to Adjuvant Radiation Field Design

    Energy Technology Data Exchange (ETDEWEB)

    Dholakia, Avani S.; Kumar, Rachit [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Raman, Siva P. [Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Moore, Joseph A.; Ellsworth, Susannah; McNutt, Todd [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Laheru, Daniel A.; Jaffee, Elizabeth [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Cameron, John L. [Department of Surgery, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Tran, Phuoc T. [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Hobbs, Robert F. [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Wolfgang, Christopher L. [Department of Surgery, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); and others

    2013-12-01

    Purpose: To generate a map of local recurrences after pancreaticoduodenectomy (PD) for patients with resectable pancreatic ductal adenocarcinoma (PDA) and to model an adjuvant radiation therapy planning treatment volume (PTV) that encompasses a majority of local recurrences. Methods and Materials: Consecutive patients with resectable PDA undergoing PD and 1 or more computed tomography (CT) scans more than 60 days after PD at our institution were reviewed. Patients were divided into 3 groups: no adjuvant treatment (NA), chemotherapy alone (CTA), or chemoradiation (CRT). Cross-sectional scans were centrally reviewed, and local recurrences were plotted to scale with respect to the celiac axis (CA), superior mesenteric artery (SMA), and renal veins on 1 CT scan of a template post-PD patient. An adjuvant clinical treatment volume comprising 90% of local failures based on standard expansions of the CA and SMA was created and simulated on 3 post-PD CT scans to assess the feasibility of this planning approach. Results: Of the 202 patients in the study, 40 (20%), 34 (17%), and 128 (63%) received NA, CTA, and CRT adjuvant therapy, respectively. The rate of margin-positive resections was greater in CRT patients than in CTA patients (28% vs 9%, P=.023). Local recurrence occurred in 90 of the 202 patients overall (45%) and in 19 (48%), 22 (65%), and 49 (38%) in the NA, CTA, and CRT groups, respectively. Ninety percent of recurrences were within a 3.0-cm right-lateral, 2.0-cm left-lateral, 1.5-cm anterior, 1.0-cm posterior, 1.0-cm superior, and 2.0-cm inferior expansion of the combined CA and SMA contours. Three simulated radiation treatment plans using these expansions with adjustments to avoid nearby structures were created to demonstrate the use of this treatment volume. Conclusions: Modified PTVs targeting high-risk areas may improve local control while minimizing toxicities, allowing dose escalation with intensity-modulated or stereotactic body radiation therapy.

  7. Mapping Patterns of Local Recurrence After Pancreaticoduodenectomy for Pancreatic Adenocarcinoma: A New Approach to Adjuvant Radiation Field Design

    International Nuclear Information System (INIS)

    Dholakia, Avani S.; Kumar, Rachit; Raman, Siva P.; Moore, Joseph A.; Ellsworth, Susannah; McNutt, Todd; Laheru, Daniel A.; Jaffee, Elizabeth; Cameron, John L.; Tran, Phuoc T.; Hobbs, Robert F.; Wolfgang, Christopher L.

    2013-01-01

    Purpose: To generate a map of local recurrences after pancreaticoduodenectomy (PD) for patients with resectable pancreatic ductal adenocarcinoma (PDA) and to model an adjuvant radiation therapy planning treatment volume (PTV) that encompasses a majority of local recurrences. Methods and Materials: Consecutive patients with resectable PDA undergoing PD and 1 or more computed tomography (CT) scans more than 60 days after PD at our institution were reviewed. Patients were divided into 3 groups: no adjuvant treatment (NA), chemotherapy alone (CTA), or chemoradiation (CRT). Cross-sectional scans were centrally reviewed, and local recurrences were plotted to scale with respect to the celiac axis (CA), superior mesenteric artery (SMA), and renal veins on 1 CT scan of a template post-PD patient. An adjuvant clinical treatment volume comprising 90% of local failures based on standard expansions of the CA and SMA was created and simulated on 3 post-PD CT scans to assess the feasibility of this planning approach. Results: Of the 202 patients in the study, 40 (20%), 34 (17%), and 128 (63%) received NA, CTA, and CRT adjuvant therapy, respectively. The rate of margin-positive resections was greater in CRT patients than in CTA patients (28% vs 9%, P=.023). Local recurrence occurred in 90 of the 202 patients overall (45%) and in 19 (48%), 22 (65%), and 49 (38%) in the NA, CTA, and CRT groups, respectively. Ninety percent of recurrences were within a 3.0-cm right-lateral, 2.0-cm left-lateral, 1.5-cm anterior, 1.0-cm posterior, 1.0-cm superior, and 2.0-cm inferior expansion of the combined CA and SMA contours. Three simulated radiation treatment plans using these expansions with adjustments to avoid nearby structures were created to demonstrate the use of this treatment volume. Conclusions: Modified PTVs targeting high-risk areas may improve local control while minimizing toxicities, allowing dose escalation with intensity-modulated or stereotactic body radiation therapy

  8. An Efficient Approach for Identifying Stable Lobes with Discretization Method

    Directory of Open Access Journals (Sweden)

    Baohai Wu

    2013-01-01

    Full Text Available This paper presents a new approach for quick identification of chatter stability lobes with discretization method. Firstly, three different kinds of stability regions are defined: absolute stable region, valid region, and invalid region. Secondly, while identifying the chatter stability lobes, three different regions within the chatter stability lobes are identified with relatively large time intervals. Thirdly, stability boundary within the valid regions is finely calculated to get exact chatter stability lobes. The proposed method only needs to test a small portion of spindle speed and cutting depth set; about 89% computation time is savedcompared with full discretization method. It spends only about10 minutes to get exact chatter stability lobes. Since, based on discretization method, the proposed method can be used for different immersion cutting including low immersion cutting process, the proposed method can be directly implemented in the workshop to promote machining parameters selection efficiency.

  9. Brain networks, structural realism, and local approaches to the scientific realism debate.

    Science.gov (United States)

    Yan, Karen; Hricko, Jonathon

    2017-08-01

    We examine recent work in cognitive neuroscience that investigates brain networks. Brain networks are characterized by the ways in which brain regions are functionally and anatomically connected to one another. Cognitive neuroscientists use various noninvasive techniques (e.g., fMRI) to investigate these networks. They represent them formally as graphs. And they use various graph theoretic techniques to analyze them further. We distinguish between knowledge of the graph theoretic structure of such networks (structural knowledge) and knowledge of what instantiates that structure (nonstructural knowledge). And we argue that this work provides structural knowledge of brain networks. We explore the significance of this conclusion for the scientific realism debate. We argue that our conclusion should not be understood as an instance of a global structural realist claim regarding the structure of the unobservable part of the world, but instead, as a local structural realist attitude towards brain networks in particular. And we argue that various local approaches to the realism debate, i.e., approaches that restrict realist commitments to particular theories and/or entities, are problematic insofar as they don't allow for the possibility of such a local structural realist attitude. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. A Local Region of Interest Imaging Method for Electrical Impedance Tomography with Internal Electrodes

    Directory of Open Access Journals (Sweden)

    Hyeuknam Kwon

    2013-01-01

    Full Text Available Electrical Impedance Tomography (EIT is a very attractive functional imaging method despite the low sensitivity and resolution. The use of internal electrodes with the conventional reconstruction algorithms was not enough to enhance image resolution and accuracy in the region of interest (ROI. We propose a local ROI imaging method with internal electrodes developed from careful analysis of the sensitivity matrix that is designed to reduce the sensitivity of the voxels outside the local region and optimize the sensitivity of the voxel inside the local region. We perform numerical simulations and physical measurements to demonstrate the localized EIT imaging method. In preliminary results with multiple objects we show the benefits of using an internal electrode and the improved resolution due to the local ROI image reconstruction method. The sensitivity is further increased by allowing the surface electrodes to be unevenly spaced with a higher density of surface electrodes near the ROI. Also, we analyse how much the image quality is improved using several performance parameters for comparison. While these have not yet been studied in depth, it convincingly shows an improvement in local sensitivity in images obtained with an internal electrode in comparison to a standard reconstruction method.

  11. Modeling the thermal behavior of fluid flow inside channels using an artificial locally linear neuro-fuzzy approach

    Directory of Open Access Journals (Sweden)

    Azadeh Hashemian

    2008-06-01

    Full Text Available Enhanced surface heat exchangers are commonly used all worldwide. If applicable, due to their complicated geometry, simulating corrugated plate heat exchangers is a time-consuming process. In the present study, first we simulate the heat transfer in a sharp V-shape corrugation cell with constant temperature walls; then, we use a Locally Linear Neuro-Fuzzy method based on a radial basis function (RBFs to model the temperature field in the whole channel. New approach is developed to deal with fast computational and low memory resources that can be used with the largest available data sets. The purpose of the research is to reveal the advantages of proposed Neuro-Fuzzy model as a powerful modeling system designed for predicting and to make a fair comparison between it and the successful FLUENT simulated approaches in its best structures.

  12. A novel chaotic particle swarm optimization approach using Henon map and implicit filtering local search for economic load dispatch

    International Nuclear Information System (INIS)

    Coelho, Leandro dos Santos; Mariani, Viviana Cocco

    2009-01-01

    Particle swarm optimization (PSO) is a population-based swarm intelligence algorithm driven by the simulation of a social psychological metaphor instead of the survival of the fittest individual. Based on the chaotic systems theory, this paper proposed a novel chaotic PSO combined with an implicit filtering (IF) local search method to solve economic dispatch problems. Since chaotic mapping enjoys certainty, ergodicity and the stochastic property, the proposed PSO introduces chaos mapping using Henon map sequences which increases its convergence rate and resulting precision. The chaotic PSO approach is used to produce good potential solutions, and the IF is used to fine-tune of final solution of PSO. The hybrid methodology is validated for a test system consisting of 13 thermal units whose incremental fuel cost function takes into account the valve-point loading effects. Simulation results are promising and show the effectiveness of the proposed approach.

  13. A comparison of conventional local approach and the short crack approach to fatigue crack initiation at a notch

    Energy Technology Data Exchange (ETDEWEB)

    Ranganathan, Narayanaswami; Leroy, Rene; Tougui, Abdellah [Laboratoire de Mecanique et Rheologie, Universite Francois Rabelais de Tours, Polytech Tours, Departement Mecanique et Conception de Systemes, Tours (France)

    2009-09-15

    Methods to estimate fatigue crack initiation life at a notch tip are compared. The methods used determine the strain amplitudes at the notch tip using Neuber's or Glinka's approximation. In conventional approaches, equivalent-damage levels are determined, using appropriate strain-life relationships coupled with damage-summation models. In the short-crack approach, a crack-like defect is assumed to exist at the notch tip. It is shown that the short-crack concept can be successfully applied to predict crack-initiation behavior at a notch. Model predictions are compared with carefully designed experiments. It is shown that model predictions are very close to experimentally measured lives under an aircraft-wing loading spectrum. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  14. Management of Sustainable Energy Efficient Development at the Local Level: Stakeholder-Oriented Approach

    Directory of Open Access Journals (Sweden)

    Horban Vasylyna B.

    2016-11-01

    Full Text Available There presented a theoretical rationale for the expediency of using the stakeholder-oriented approach to improve the process of management of sustainable energy efficient development at the local level. The evolution of theories by scientific schools that studied the concepts of «stakeholders» and «interested parties» is analyzed and generalized. A classification of types of stakeholders in the context of eighteen typological features is suggested, which allows to more effectively align their interests and contributes to establishing constructive forms of cooperation in order to achieve efficient final results. An algorithm of interaction with interested parties in achieving the goals of sustainable energy efficient development at the local level is elaborated. Typical motivational interests of stakeholders at the local level in the field of sustainable energy efficient development (on the example of Ukraine are identified. Instruments of prioritization of stakeholders depending on the life cycle stages of energy efficiency projects are proposed. The results obtained in the course of the research can be used to develop local energy efficient programs, business plans and feasibility studies for energy efficient projects.

  15. A Low Cost Sensors Approach for Accurate Vehicle Localization and Autonomous Driving Application.

    Science.gov (United States)

    Vivacqua, Rafael; Vassallo, Raquel; Martins, Felipe

    2017-10-16

    Autonomous driving in public roads requires precise localization within the range of few centimeters. Even the best current precise localization system based on the Global Navigation Satellite System (GNSS) can not always reach this level of precision, especially in an urban environment, where the signal is disturbed by surrounding buildings and artifacts. Laser range finder and stereo vision have been successfully used for obstacle detection, mapping and localization to solve the autonomous driving problem. Unfortunately, Light Detection and Ranging (LIDARs) are very expensive sensors and stereo vision requires powerful dedicated hardware to process the cameras information. In this context, this article presents a low-cost architecture of sensors and data fusion algorithm capable of autonomous driving in narrow two-way roads. Our approach exploits a combination of a short-range visual lane marking detector and a dead reckoning system to build a long and precise perception of the lane markings in the vehicle's backwards. This information is used to localize the vehicle in a map, that also contains the reference trajectory for autonomous driving. Experimental results show the successful application of the proposed system on a real autonomous driving situation.

  16. Local adaptive capacity as an alternative approach in dealing with hydrometeorological risk at Depok Peri-Urban City

    Science.gov (United States)

    Fitrinitia, I. S.; Junadi, P.; Sutanto, E.; Nugroho, D. A.; Zubair, A.; Suyanti, E.

    2018-03-01

    Located in a tropical area, cities in Indonesia are vulnerable to hydrometeorological risks such as flood and landslide and thus become prone to the climate change effects. Moreover, peri-urban cities had double burden as the consequences of main city spill over and also lack of urban facilities in overcoming the disaster. In another perspective, the city has many alternative resources to recover, so its create urban resiliency. Depok city becomes a case study of this research regarding with its development following the impact of Jakarta growth. This research purposes to capture how the local city dwellers could anticipate and adaptive with flood and landslide with their own mitigation version. Through mix method and spatial analysis using GIS techniques, it derives the two comparison approach, the normative and alternative that had been done by the city dwellers. It uses a spatial analysis to have a big picture of Depok and its environmental changing. It also divided into 4 local group of communities as a representative of city dwellers regarding the characteristic of a settlement with their level of risk. The result found type or characteristic of settlement which influenced the local adaptive capacity, from the establishment of infrastructure, health fulfillment and social livelihood with different kind of methods.

  17. A versatile method to grow localized arrays of nanowires for highly sensitive capacitive devices

    DEFF Research Database (Denmark)

    Antohe, V.A.; Radu, A.; Yunus, S.

    2008-01-01

    We propose a new approach to increase the detection efficiency of the capacitive sensing devices, by growing vertically aligned nanowires arrays, localized and confined on small interdigited electrodes structures. The metallic tracks are made using optical lithography, and the nanowires are reali...

  18. Institutional Framework for Support of Local Entrepreneurship Within Leader Approach in Slovakia

    Directory of Open Access Journals (Sweden)

    Bumbalová Monika

    2017-12-01

    Full Text Available Current development of rural areas of Slovakia is not fully reflecting the measures taken at the level of the European Union. Contrary, the differences between the territories seem to be deepening. When analysing the critical factors, job creation together with unemployment seem to be among the most pressing ones. The academics believe that the local entrepreneurship and development of small and medium size enterprises (SME in rural areas have significant impact on accelerating the development of these communities, yet, only limited measures are taken to support them. Therefore, the main objective of the paper is to analyze the institutional framework for support of local SME within implementation of the LEADER approach as a direct instrument of the rural development policy. The emphasis was put on the last programming period (2007 – 2013 and the conditions set for the current programming period (2014 – 2020.

  19. Investigation of AA2024-T3 surfaces modified by cerium compounds: A localized approach

    International Nuclear Information System (INIS)

    Paussa, L.; Andreatta, F.; De Felicis, D.; Bemporad, E.; Fedrizzi, L.

    2014-01-01

    Highlights: •The precipitation of cerium compounds occurs on the entire AA2024-T3 surface. •The matrix is less involved in the cerium precipitation. •Cerium intensely precipitates on Mg-rich IM particles. •The electrochemical behavior of Mg-rich IM particles influences the mechanism of cerium precipitation. -- Abstract: The precipitation of cerium compounds on polished AA2024-T3 surfaces was investigated following an electrochemical and microstructural localized approach. It was found that cerium precipitation occurs on the entire surface covering intermetallic particles and the matrix as well. The matrix is the region where the precipitation of cerium is less favoured. The highest amount of cerium was observed on magnesium-rich intermetallic particles. The localized analyses suggest that precipitation of cerium on magnesium-rich intermetallic particles could happen following two mechanisms: the former based on a potential reversal of the intermetallic particles and the latter due to a partial magnesium dissolution

  20. A Simple Approach for Local Contact Angle Determination on a Heterogeneous Surface

    KAUST Repository

    Wu, Jinbo

    2011-05-17

    We report a simple approach for measuring the local contact angle of liquids on a heterogeneous surface consisting of intersected hydrophobic and hydrophilic patch arrays, specifically by employing confocal microscopy and the addition of a very low concentration of Rhodamine-B (RB) (2 × 10 -7 mol/L). Interestingly, RB at that concentration was found to be aggregated at the air-liquid and solid (hydrophobic patch only)-liquid interfaces, which helps us to distinguish the liquid and solid interfaces as well as hydrophobic and hydrophilic patches by their corresponding fluorescent intensities. From the measured local contact angles, the line tension can be easily derived and the value is found to be (-2.06-1.53) × 10-6 J/m. © 2011 American Chemical Society.

  1. Total System Performance Assessment - License Application Methods and Approach

    Energy Technology Data Exchange (ETDEWEB)

    J. McNeish

    2003-12-08

    ''Total System Performance Assessment-License Application (TSPA-LA) Methods and Approach'' provides the top-level method and approach for conducting the TSPA-LA model development and analyses. The method and approach is responsive to the criteria set forth in Total System Performance Assessment Integration (TSPAI) Key Technical Issues (KTIs) identified in agreements with the U.S. Nuclear Regulatory Commission, the ''Yucca Mountain Review Plan'' (YMRP), ''Final Report'' (NRC 2003 [163274]), and the NRC final rule 10 CFR Part 63 (NRC 2002 [156605]). This introductory section provides an overview of the TSPA-LA, the projected TSPA-LA documentation structure, and the goals of the document. It also provides a brief discussion of the regulatory framework, the approach to risk management of the development and analysis of the model, and the overall organization of the document. The section closes with some important conventions that are used in this document.

  2. A PRACTICAL APPROACH TO THE GROUND OSCILLATION VELOCITY MEASUREMENT METHOD

    Directory of Open Access Journals (Sweden)

    Siniša Stanković

    2017-01-01

    Full Text Available The use of an explosive’s energy during blasting includes undesired effects on the environment. The seismic influence of a blast, as a major undesired effect, is determined by many national standards, recommendations and calculations where the main parameter is ground oscillation velocity at the field measurement location. There are a few approaches and methods for calculation of expected ground oscillation velocities according to charge weight per delay and the distance from the blast to the point of interest. Utilizations of these methods and formulas do not provide satisfactory results, thus the measured values on diverse distance from the blast field more or less differ from values given by previous calculations. Since blasting works are executed in diverse geological conditions, the aim of this research is the development of a practical and reliable approach which will give a different model for each construction site where blasting works have been or will be executed. The approach is based on a greater number of measuring points in line from the blast field at predetermined distances. This new approach has been compared with other generally used methods and formulas through the use of measurements taken during research along with measurements from several previously executed projects. The results confirmed that the suggested model gives more accurate values.

  3. Keyframes Global Map Establishing Method for Robot Localization through Content-Based Image Matching

    Directory of Open Access Journals (Sweden)

    Tianyang Cao

    2017-01-01

    Full Text Available Self-localization and mapping are important for indoor mobile robot. We report a robust algorithm for map building and subsequent localization especially suited for indoor floor-cleaning robots. Common methods, for example, SLAM, can easily be kidnapped by colliding or disturbed by similar objects. Therefore, keyframes global map establishing method for robot localization in multiple rooms and corridors is needed. Content-based image matching is the core of this method. It is designed for the situation, by establishing keyframes containing both floor and distorted wall images. Image distortion, caused by robot view angle and movement, is analyzed and deduced. And an image matching solution is presented, consisting of extraction of overlap regions of keyframes extraction and overlap region rebuild through subblocks matching. For improving accuracy, ceiling points detecting and mismatching subblocks checking methods are incorporated. This matching method can process environment video effectively. In experiments, less than 5% frames are extracted as keyframes to build global map, which have large space distance and overlap each other. Through this method, robot can localize itself by matching its real-time vision frames with our keyframes map. Even with many similar objects/background in the environment or kidnapping robot, robot localization is achieved with position RMSE <0.5 m.

  4. Local blur analysis and phase error correction method for fringe projection profilometry systems.

    Science.gov (United States)

    Rao, Li; Da, Feipeng

    2018-05-20

    We introduce a flexible error correction method for fringe projection profilometry (FPP) systems in the presence of local blur phenomenon. Local blur caused by global light transport such as camera defocus, projector defocus, and subsurface scattering will cause significant systematic errors in FPP systems. Previous methods, which adopt high-frequency patterns to separate the direct and global components, fail when the global light phenomenon occurs locally. In this paper, the influence of local blur on phase quality is thoroughly analyzed, and a concise error correction method is proposed to compensate the phase errors. For defocus phenomenon, this method can be directly applied. With the aid of spatially varying point spread functions and local frontal plane assumption, experiments show that the proposed method can effectively alleviate the system errors and improve the final reconstruction accuracy in various scenes. For a subsurface scattering scenario, if the translucent object is dominated by multiple scattering, the proposed method can also be applied to correct systematic errors once the bidirectional scattering-surface reflectance distribution function of the object material is measured.

  5. Multiple Signal Classification Algorithm Based Electric Dipole Source Localization Method in an Underwater Environment

    Directory of Open Access Journals (Sweden)

    Yidong Xu

    2017-10-01

    Full Text Available A novel localization method based on multiple signal classification (MUSIC algorithm is proposed for positioning an electric dipole source in a confined underwater environment by using electric dipole-receiving antenna array. In this method, the boundary element method (BEM is introduced to analyze the boundary of the confined region by use of a matrix equation. The voltage of each dipole pair is used as spatial-temporal localization data, and it does not need to obtain the field component in each direction compared with the conventional fields based localization method, which can be easily implemented in practical engineering applications. Then, a global-multiple region-conjugate gradient (CG hybrid search method is used to reduce the computation burden and to improve the operation speed. Two localization simulation models and a physical experiment are conducted. Both the simulation results and physical experiment result provide accurate positioning performance, with the help to verify the effectiveness of the proposed localization method in underwater environments.

  6. Numerical evaluation of the five sensor probe method for measurement of local interfacial area concentration of cap bubbles

    International Nuclear Information System (INIS)

    Euh, D.J.; Yun, B.J.; Song, C.H.; Kwon, T.S.; Chung, M.K.; Lee, U.C.

    2000-01-01

    The interfacial area concentration (IAC) is one of the most important parameters in the two-fluid model for two-phase flow analysis. The IAC can be measured by a local conductivity probe method that uses the difference of conductivity between water and air/steam. The number of sensors in the conductivity probe may be differently chosen by considering the flow regime of two-phase flow. The four sensor conductivity probe method predicts the IAC without any assumptions of the bubble shape. The local IAC can be obtained by measuring the three dimensional velocity vector elements at the measuring point, and the directional cosines of the sensors. The five sensor conductivity probe method proposed in this study is based on the four sensor probe method. With the five sensor probe, the local IAC for a given referred measuring area of the probe can be predicted more exactly. In this paper, the mathematical approach of the five sensor probe method for measuring the IAC is described, and a numerical simulation is carried out for ideal cap bubbles of which the sizes and locations are determined by a random number generator. (author)

  7. Method for local temperature measurement in a nanoreactor for in situ high-resolution electron microscopy.

    Science.gov (United States)

    Vendelbo, S B; Kooyman, P J; Creemer, J F; Morana, B; Mele, L; Dona, P; Nelissen, B J; Helveg, S

    2013-10-01

    In situ high-resolution transmission electron microscopy (TEM) of solids under reactive gas conditions can be facilitated by microelectromechanical system devices called nanoreactors. These nanoreactors are windowed cells containing nanoliter volumes of gas at ambient pressures and elevated temperatures. However, due to the high spatial confinement of the reaction environment, traditional methods for measuring process parameters, such as the local temperature, are difficult to apply. To address this issue, we devise an electron energy loss spectroscopy (EELS) method that probes the local temperature of the reaction volume under inspection by the electron beam. The local gas density, as measured using quantitative EELS, is combined with the inherent relation between gas density and temperature, as described by the ideal gas law, to obtain the local temperature. Using this method we determined the temperature gradient in a nanoreactor in situ, while the average, global temperature was monitored by a traditional measurement of the electrical resistivity of the heater. The local gas temperatures had a maximum of 56 °C deviation from the global heater values under the applied conditions. The local temperatures, obtained with the proposed method, are in good agreement with predictions from an analytical model. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Budgetary Approach to Project Management by Percentage of Completion Method

    Directory of Open Access Journals (Sweden)

    Leszek Borowiec

    2011-07-01

    Full Text Available Efficient and effective project management process is made possible by the use of methods and techniques of project management. The aim of this paper is to present the problems of project management by using Percentage of Completion method. The research material was gathered based on the experience in implementing this method by the Johnson Controls International Company. The article attempts to demonstrate the validity of the thesis that the POC project management method, allows for effective implementation and monitoring of the project and thus is an effective tool in the managing of companies which exploit the budgetary approach. The study presents planning process of basic parameters affecting the effectiveness of the project (such as costs, revenue, margin and characterized how the primary measurements used to evaluate it. The present theme is illustrating by numerous examples for showing the essence of the raised problems and the results are presenting by using descriptive methods, graphical and tabular.

  9. Assessing and evaluating multidisciplinary translational teams: a mixed methods approach.

    Science.gov (United States)

    Wooten, Kevin C; Rose, Robert M; Ostir, Glenn V; Calhoun, William J; Ameredes, Bill T; Brasier, Allan R

    2014-03-01

    A case report illustrates how multidisciplinary translational teams can be assessed using outcome, process, and developmental types of evaluation using a mixed-methods approach. Types of evaluation appropriate for teams are considered in relation to relevant research questions and assessment methods. Logic models are applied to scientific projects and team development to inform choices between methods within a mixed-methods design. Use of an expert panel is reviewed, culminating in consensus ratings of 11 multidisciplinary teams and a final evaluation within a team-type taxonomy. Based on team maturation and scientific progress, teams were designated as (a) early in development, (b) traditional, (c) process focused, or (d) exemplary. Lessons learned from data reduction, use of mixed methods, and use of expert panels are explored.

  10. A localized in vivo detection method for lactate using zero quantum coherence techniques

    NARCIS (Netherlands)

    van Dijk, J. E.; Bosman, D. K.; Chamuleau, R. A.; Bovee, W. M.

    1991-01-01

    A method is described to selectively measure lactate in vivo using proton zero quantum coherence techniques. The signal from lipids is eliminated. A surface coil and additionally slice selective localization are used. The resulting spectra demonstrate the good performance of the method

  11. Noise source separation of diesel engine by combining binaural sound localization method and blind source separation method

    Science.gov (United States)

    Yao, Jiachi; Xiang, Yang; Qian, Sichong; Li, Shengyang; Wu, Shaowei

    2017-11-01

    In order to separate and identify the combustion noise and the piston slap noise of a diesel engine, a noise source separation and identification method that combines a binaural sound localization method and blind source separation method is proposed. During a diesel engine noise and vibration test, because a diesel engine has many complex noise sources, a lead covering method was carried out on a diesel engine to isolate other interference noise from the No. 1-5 cylinders. Only the No. 6 cylinder parts were left bare. Two microphones that simulated the human ears were utilized to measure the radiated noise signals 1 m away from the diesel engine. First, a binaural sound localization method was adopted to separate the noise sources that are in different places. Then, for noise sources that are in the same place, a blind source separation method is utilized to further separate and identify the noise sources. Finally, a coherence function method, continuous wavelet time-frequency analysis method, and prior knowledge of the diesel engine are combined to further identify the separation results. The results show that the proposed method can effectively separate and identify the combustion noise and the piston slap noise of a diesel engine. The frequency of the combustion noise and the piston slap noise are respectively concentrated at 4350 Hz and 1988 Hz. Compared with the blind source separation method, the proposed method has superior separation and identification effects, and the separation results have fewer interference components from other noise.

  12. New method for the exact determination of the effective conductivity and the local field in RLC networks

    International Nuclear Information System (INIS)

    Zekri, L.; Zekri, N.; Bouamrane, R.

    1999-10-01

    We present a new numerical method for determining exactly the effective conductivity and the local field for random RLC networks. This method is compared to a real space renormalization group method and the Frank and Lobb method. Although our method is slower than the Frank and Lobb method, it also computes exactly the local field for large size systems. We also show that the renormalization group method fails in determining the local field. (author)

  13. A local analytic approach for the fast solution of the Fokker-Planck equation

    International Nuclear Information System (INIS)

    Sajjadi, S.G.; Nicholas, D.J.

    1987-11-01

    In this report we describe a method of obtaining a closed form for the Focker-Planck equation rendering it amenable to solution in time-step with a complete hydrodynamic treatment of a plasma. We present a local expression for the heat flux, by solving the Focker-Planck equation for electrons in one space and two velocity dimensions in the presence of a self consistent electronic field. (author)

  14. Locally self-consistent Green’s function approach to the electronic structure problem

    DEFF Research Database (Denmark)

    Abrikosov, I.A.; Simak, S.I.; Johansson, B.

    1997-01-01

    scattering problem in a local interaction zone (LIZ) embedded in an effective medium judiciously chosen to minimize the size of the, LIZ. The excellent real-space convergence of the LSGF calculations and the reliability of its results are demonstrated for a broad spectrum of metallic alloys with different...... degree of order. The relation of the convergence of our method to fundamental properties of the system, that is, the effective cluster interactions, is discussed....

  15. Quantum group structure and local fields in the algebraic approach to 2D gravity

    CERN Document Server

    Schnittger, Jens

    1994-01-01

    This review contains a summary of work by J.-L. Gervais and the author on the operator approach to 2d gravity. Special emphasis is placed on the construction of local observables -the Liouville exponentials and the Liouville field itself - and the underlying algebra of chiral vertex operators. The double quantum group structure arising from the presence of two screening charges is discussed and the generalized algebra and field operators are derived. In the last part, we show that our construction gives rise to a natural definition of a quantum tau function, which is a noncommutative version of the classical group-theoretic representation of the Liouville fields by Leznov and Saveliev.

  16. Maximum likelihood approach to “informed” Sound Source Localization for Hearing Aid applications

    DEFF Research Database (Denmark)

    Farmani, Mojtaba; Pedersen, Michael Syskind; Tan, Zheng-Hua

    2015-01-01

    Most state-of-the-art Sound Source Localization (SSL) algorithms have been proposed for applications which are "uninformed'' about the target sound content; however, utilizing a wireless microphone worn by a target talker, enables recent Hearing Aid Systems (HASs) to access to an almost noise......-free sound signal of the target talker at the HAS via the wireless connection. Therefore, in this paper, we propose a maximum likelihood (ML) approach, which we call MLSSL, to estimate the Direction of Arrival (DoA) of the target signal given access to the target signal content. Compared with other "informed...

  17. A mixed-methods approach to systematic reviews.

    Science.gov (United States)

    Pearson, Alan; White, Heath; Bath-Hextall, Fiona; Salmond, Susan; Apostolo, Joao; Kirkpatrick, Pamela

    2015-09-01

    There are an increasing number of published single-method systematic reviews that focus on different types of evidence related to a particular topic. As policy makers and practitioners seek clear directions for decision-making from systematic reviews, it is likely that it will be increasingly difficult for them to identify 'what to do' if they are required to find and understand a plethora of syntheses related to a particular topic.Mixed-methods systematic reviews are designed to address this issue and have the potential to produce systematic reviews of direct relevance to policy makers and practitioners.On the basis of the recommendations of the Joanna Briggs Institute International Mixed Methods Reviews Methodology Group in 2012, the Institute adopted a segregated approach to mixed-methods synthesis as described by Sandelowski et al., which consists of separate syntheses of each component method of the review. Joanna Briggs Institute's mixed-methods synthesis of the findings of the separate syntheses uses a Bayesian approach to translate the findings of the initial quantitative synthesis into qualitative themes and pooling these with the findings of the initial qualitative synthesis.

  18. The effect of walking speed on local dynamic stability is sensitive to calculation methods

    DEFF Research Database (Denmark)

    Stenum, Jan; Bruijn, Sjoerd M; Jensen, Bente Rona

    2014-01-01

    Local dynamic stability has been assessed by the short-term local divergence exponent (λS), which quantifies the average rate of logarithmic divergence of infinitesimally close trajectories in state space. Both increased and decreased local dynamic stability at faster walking speeds have been...... reported. This might pertain to methodological differences in calculating λS. Therefore, the aim was to test if different calculation methods would induce different effects of walking speed on local dynamic stability. Ten young healthy participants walked on a treadmill at five speeds (60%, 80%, 100%, 120......% and 140% of preferred walking speed) for 3min each, while upper body accelerations in three directions were sampled. From these time-series, λS was calculated by three different methods using: (a) a fixed time interval and expressed as logarithmic divergence per stride-time (λS-a), (b) a fixed number...

  19. A new approach for peat inventory methods; Turvetutkimusten menetelmaekehitystarkastelu

    Energy Technology Data Exchange (ETDEWEB)

    Laatikainen, M.; Leino, J.; Lerssi, J.; Torppa, J.; Turunen, J. Email: jukka.turunen@gtk.fi

    2011-07-01

    Development of the new peatland inventory method started in 2009. There was a need to investigate whether new methods and tools could be developed cost-effectively so field inventory work would more completely cover the whole peatland area and the quality and liability of the final results would remain at a high level. The old inventory method in place at the Geological Survey of Finland (GTK) is based on the main transect and cross transect approach across a peatland area. The goal of this study was to find a practical grid-based method linked to the geographic information system suitable for field conditions. the triangle-grid method with even distance between the study points was found to be the most suitable approach. A new Ramac-ground penetrating radar was obtained by the GTK in 2009, and it was concluded in the study of new peatland inventory methods. This radar model is relatively light and very suitable, for example, to the forestry drained peatlands, which are often difficult to cross because of the intensive ditch network. the goal was to investigate the best working methods for the ground penetrating radar to optimize its use in the large-scale peatland inventory. Together with the new field inventory methods, a novel interpolation-based method (MITTI) for modelling peat depths was developed. MITTI makes it possible to take advantage of all the available peat-depth data including, at the moment, aerogeophysical and ground penetrating radar measurements, drilling data and the mire outline. The characteristic uncertainties of each data type are taken into account and, in addition to the depth model itself, an uncertainty map of the model is computed. Combined with the grid-based field inventory method, this multi-approach provides better tools to more accurately estimate the peat depths, peat amounts and peat type distributions. The development of the new peatland inventory method was divided into four separate sections: (1) Development of new field

  20. Local resource based approach to maintaining and preserving rural local access roads assets: Siyatentela institutional framework and governance case study discourses

    CSIR Research Space (South Africa)

    Chakwizira, J

    2010-10-01

    Full Text Available and other development agencies focusing on the use of appropriate technologies for civil construction be it in the road, transport, water, agriculture or environmental sectors (World Bank 2001; ILO, 2002; Clegg, 2003). The seminal study conducted... and contribution of local resource based approach to rural and community access roads requires a review of the labour based initiatives in the road, transport and infrastructure sub-sector. An apt statement that captures the essence of building local community...

  1. Accurate 3D Localization Method for Public Safety Applications in Vehicular Ad-hoc Networks

    KAUST Repository

    Ansari, Abdul Rahim

    2018-04-10

    Vehicular ad hoc networks (VANETs) represent a very promising research area because of their ever increasing demand, especially for public safety applications. In VANETs vehicles communicate with each other to exchange road maps and traffic information. In many applications, location-based services are the main service, and localization accuracy is the main problem. VANETs also require accurate vehicle location information in real time. To fulfill this requirement, a number of algorithms have been proposed; however, the location accuracy required for public safety applications in VANETs has not been achieved. In this paper, an improved subspace algorithm is proposed for time of arrival (TOA) measurements in VANETs localization. The proposed method gives a closed-form solution and it is robust for large measurement noise, as it is based on the eigen form of a scalar product and dimensionality. Furthermore, we developed the Cramer-Rao Lower Bound (CRLB) to evaluate the performance of the proposed 3D VANETs localization method. The performance of the proposed method was evaluated by comparison with the CRLB and other localization algorithms available in the literature through numerous simulations. Simulation results show that the proposed 3D VANETs localization method is better than the literature methods especially for fewer anchors at road side units and large noise variance.

  2. ULTRACAVITATION METHOD OF EVALUATION IN THE REDUCTION OF LOCALIZED FAT IN WOMEN

    OpenAIRE

    L. Petraglia; D. R. X. O. Crege; J. L. Dullius; A. E. Bighetti

    2017-01-01

    This study evaluated cosmetic fat reduction methods that cause localized lipolysis and that are not invasive. The use of a differentiated ultrasound called Ultracavitation was evaluated, it causes reduction of localized fat in the infra abdominal region. 30 women aged 30-45 years old, healthy, sedentary were evaluated; they were separated into two groups subjected to 12 treatment sessions in infra abdominal region, once a week, alone or combined with aerobic exercise. Photographic recording w...

  3. Anchor-Free Localization Method for Mobile Targets in Coal Mine Wireless Sensor Networks

    OpenAIRE

    Pei, Zhongmin; Deng, Zhidong; Xu, Shuo; Xu, Xiao

    2009-01-01

    Severe natural conditions and complex terrain make it difficult to apply precise localization in underground mines. In this paper, an anchor-free localization method for mobile targets is proposed based on non-metric multi-dimensional scaling (Multi-dimensional Scaling: MDS) and rank sequence. Firstly, a coal mine wireless sensor network is constructed in underground mines based on the ZigBee technology. Then a non-metric MDS algorithm is imported to estimate the reference nodes’ location. Fi...

  4. Hierarchical Leak Detection and Localization Method in Natural Gas Pipeline Monitoring Sensor Networks

    OpenAIRE

    Ning Yu; Renjian Feng; Jiangwen Wan; Yinfeng Wu; Yang Yu

    2011-01-01

    In light of the problems of low recognition efficiency, high false rates and poor localization accuracy in traditional pipeline security detection technology, this paper proposes a type of hierarchical leak detection and localization method for use in natural gas pipeline monitoring sensor networks. In the signal preprocessing phase, original monitoring signals are dealt with by wavelet transform technology to extract the single mode signals as well as characteristic parameters. In the initia...

  5. An Improved Local Gradient Method for Sea Surface Wind Direction Retrieval from SAR Imagery

    Directory of Open Access Journals (Sweden)

    Lizhang Zhou

    2017-06-01

    Full Text Available Sea surface wind affects the fluxes of energy, mass and momentum between the atmosphere and ocean, and therefore regional and global weather and climate. With various satellite microwave sensors, sea surface wind can be measured with large spatial coverage in almost all-weather conditions, day or night. Like any other remote sensing measurements, sea surface wind measurement is also indirect. Therefore, it is important to develop appropriate wind speed and direction retrieval models for different types of microwave instruments. In this paper, a new sea surface wind direction retrieval method from synthetic aperture radar (SAR imagery is developed. In the method, local gradients are computed in frequency domain by combining the operation of smoothing and computing local gradients in one step to simplify the process and avoid the difference approximation. This improved local gradients (ILG method is compared with the traditional two-dimensional fast Fourier transform (2D FFT method and local gradients (LG method, using interpolating wind directions from the European Centre for Medium-Range Weather Forecast (ECMWF reanalysis data and the Cross-Calibrated Multi-Platform (CCMP wind vector product. The sensitivities to the salt-and-pepper noise, the additive noise and the multiplicative noise are analyzed. The ILG method shows a better performance of retrieval wind directions than the other two methods.

  6. Kinematic Localization for Global Navigation Satellite Systems: A Kalman Filtering Approach

    Science.gov (United States)

    Tabatabaee, Mohammad Hadi

    Use of the Global Positioning System (GNSS) has expanded significantly in the past decade, especially with advances in embedded systems and the emergence of smartphones and the Internet of Things (IoT). The growing demand has stimulated research on development of GNSS techniques and programming tools. The focus of much of the research efforts have been on high-level algorithms and augmentations. This dissertation focuses on the low-level methods at the heart of GNSS systems and proposes a new methods for GNSS positioning problems based on concepts of distance geometry and the use of Kalman filters. The methods presented in this dissertation provide algebraic solutions to problems that have predominantly been solved using iterative methods. The proposed methods are highly efficient, provide accurate estimates, and exhibit a degree of robustness in the presence of unfavorable satellite geometry. The algorithm operates in two stages; an estimation of the receiver clock bias and removal of the bias from the pseudorange observables, followed by the localization of the GNSS receiver. The use of a Kalman filter in between the two stages allows for an improvement of the clock bias estimate with a noticeable impact on the position estimates. The receiver localization step has also been formulated in a linear manner allowing for the direct application of a Kalman filter without any need for linearization. The methodology has also been extended to double differential observables for high accuracy pseudorange and carrier phase position estimates.

  7. A reactive, scalable, and transferable model for molecular energies from a neural network approach based on local information

    Science.gov (United States)

    Unke, Oliver T.; Meuwly, Markus

    2018-06-01

    Despite the ever-increasing computer power, accurate ab initio calculations for large systems (thousands to millions of atoms) remain infeasible. Instead, approximate empirical energy functions are used. Most current approaches are either transferable between different chemical systems, but not particularly accurate, or they are fine-tuned to a specific application. In this work, a data-driven method to construct a potential energy surface based on neural networks is presented. Since the total energy is decomposed into local atomic contributions, the evaluation is easily parallelizable and scales linearly with system size. With prediction errors below 0.5 kcal mol-1 for both unknown molecules and configurations, the method is accurate across chemical and configurational space, which is demonstrated by applying it to datasets from nonreactive and reactive molecular dynamics simulations and a diverse database of equilibrium structures. The possibility to use small molecules as reference data to predict larger structures is also explored. Since the descriptor only uses local information, high-level ab initio methods, which are computationally too expensive for large molecules, become feasible for generating the necessary reference data used to train the neural network.

  8. Methodical approaches to development of classification state methods of regulation business activity in fishery

    OpenAIRE

    She Son Gun

    2014-01-01

    Approaches to development of classification of the state methods of regulation of economy are considered. On the basis of the provided review the complex method of state regulation of business activity is reasonable. The offered principles allow improving public administration and can be used in industry concepts and state programs on support of small business in fishery.

  9. Creative Approaches to Teaching Graduate Research Methods Workshops

    OpenAIRE

    Peter Reilly

    2017-01-01

    Engagement and deeper learning were enhanced by developing several innovative teaching strategies delivered in Research Methods workshops to Graduate Business Students.  Focusing primarily on students adopting a creative approach to formulating a valid research question for undertaking a dissertation successfully. These techniques are applicable to most subject domains to ensure student engagement.  Addressing the various multiple intelligences and learning styles existing within groups while...

  10. Methodical approach to financial stimulation of logistics managers

    OpenAIRE

    Melnykova Kateryna V.

    2014-01-01

    The article offers a methodical approach to financial stimulation of logistics managers, which allows calculation of the incentive amount with consideration of profit obtained from introduction of optimisation logistics solutions. The author generalises measures, which would allow increase of stimulation of labour of logistics managers by the enterprise top managers. The article marks out motivation factors, which exert influence upon relation of logistics managers to execution of optimisatio...

  11. Localism and energy: Negotiating approaches to embedding resilience in energy systems

    International Nuclear Information System (INIS)

    O'Brien, Geoff; Hope, Alex

    2010-01-01

    Tensions are evident in energy policy objectives between centralised top-down interconnected energy systems and localised distributed approaches. Examination of these tensions indicates that a localised approach can address a systemic problem of interconnected systems; namely vulnerability. The challenge for energy policy is to realise the interrelated goals of energy security, climate and environmental targets and social and economic issues such as fuel poverty, whilst mitigating vulnerability. The effectiveness of conventional approaches is debatable. A transition to a low carbon pathway should focus on resilience, counter to vulnerability. This article draws from on-going work which evaluates the energy aspects of a Private Finance Initiative (PFI) project to refurbish and re-build a local authority's entire stock of sheltered accommodation to high environmental standards. Initial findings suggest that whereas more conventional procurement processes tend to increase systemic vulnerability, a user focussed process driven through PFI competitive dialogue is beginning to motivate some developers to adopt innovative approaches to energy system development.

  12. Novel Approach for Prediction of Localized Necking in Case of Nonlinear Strain Paths

    Science.gov (United States)

    Drotleff, K.; Liewald, M.

    2017-09-01

    Rising customer expectations regarding design complexity and weight reduction of sheet metal components alongside with further reduced time to market implicate increased demand for process validation using numerical forming simulation. Formability prediction though often is still based on the forming limit diagram first presented in the 1960s. Despite many drawbacks in case of nonlinear strain paths and major advances in research in the recent years, the forming limit curve (FLC) is still one of the most commonly used criteria for assessing formability of sheet metal materials. Especially when forming complex part geometries nonlinear strain paths may occur, which cannot be predicted using the conventional FLC-Concept. In this paper a novel approach for calculation of FLCs for nonlinear strain paths is presented. Combining an interesting approach for prediction of FLC using tensile test data and IFU-FLC-Criterion a model for prediction of localized necking for nonlinear strain paths can be derived. Presented model is purely based on experimental tensile test data making it easy to calibrate for any given material. Resulting prediction of localized necking is validated using an experimental deep drawing specimen made of AA6014 material having a sheet thickness of 1.04 mm. The results are compared to IFU-FLC-Criterion based on data of pre-stretched Nakajima specimen.

  13. The irradiation embrittlement of two pressure vessel steels -Contribution of local approach

    Energy Technology Data Exchange (ETDEWEB)

    Soulat, P; Marini, B [CEA Centre d` Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Service de Recherches Metallurgiques Appliquees; Miannay, D; Horowitz, H [CEA Centre d` Etudes de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire; Schill, R [CEA Centre d` Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. de Mecanique et de Technologie

    1994-12-31

    Within the IAEA Coordinated Research Programme on ``Optimizing the Reactor Pressure Vessel Surveillance Programmes and their Analyses``, the French participation has been focused on the contribution of the local approach to the determination of the sensitivity to radiation embrittlement of two different pressure vessel steels: a low sensitive French forging steel (FFA) and a high sensitive ``monitor`` Japanese plate steel (JRQ) were irradiated to a fluence of 3.10{sup 19} n/cm{sup 2} at 290 C. The irradiation embrittlement of the two steels measured by the shift of Charpy V transition curves is in good agreement with the estimated shifts given by theoretical prediction. The fracture toughness properties were examined at low temperature with brittle fracture, and at service temperature (290 C), with ductile tearing. The values of K{sub 1C} or K{sub JC} for the brittle fracture and J{sub 1C} for the ductile fracture are compared to predictions established using the local approach of cleavage fracture (Weibull analysis) and the critical rate of void growth respectively. 8 refs., 14 figs., 10 tabs.

  14. First spinning cylinder test analysis by using local approach to fracture

    International Nuclear Information System (INIS)

    Eripret, C.; Rousselier, G.

    1993-01-01

    In recent years, several experimental programs on large scale specimens were organized to evaluate capabilities of the fracture mechanics concepts employed in structural integrity assessment of PWR pressure vessels. During the first spinning cylinder test, a geometry effect was experimentally pointed out and exhibited the problem of transferability of toughness data from small scale to large scale specimens. An original analysis of this test, by means of local approach to fracture is presented in this paper. Both compact tension specimen and spinning cylinder fracture behaviour were computed by using a continuum damage mechanics model developed at EDF. The authors confirmed by numerical analysis that the cylinder's resistance to ductile tearing was considerably larger than in small scale fracture mechanics specimens tests, about 50 percent. The final crack growth predicted by the model was close to the experimental value. Discrepancies in J-R curves seemed to be due to an effect of stress triaxiality and plastic zone evolution. The geometry effect inducing differences in resistance to ductile tearing of the material involved in the specimens can be investigated and explained by using local approach to fracture methodology. 14 refs., 9 figs., 2 tabs

  15. Multimodality therapy approaches, local and systemic treatment, compared with chemotherapy alone in recurrent glioblastoma

    International Nuclear Information System (INIS)

    Scorsetti, Marta; Navarria, Pierina; Pessina, Federico; Ascolese, Anna Maria; D’Agostino, Giuseppe; Tomatis, Stefano; De Rose, Fiorenza; Villa, Elisa; Maggi, Giulia; Simonelli, Matteo; Clerici, Elena; Soffietti, Riccardo; Santoro, Armando; Cozzi, Luca; Bello, Lorenzo

    2015-01-01

    Long-term local control in Glioblastoma is rarely achieved and nearly all patients relapse. In this study we evaluated the clinical effect of different treatment approaches in recurrent patients. Forty-three patients, with median age of 51 years were evaluated for salvage treatment: re-resection and/or re-irradiation plus chemotherapy or chemotherapy alone. Response was recorded using the Response Assessment in Neuro-Oncology criteria. Hematologic and non-hematologic toxicities were graded according to Common Terminology Criteria for Adverse Events 4.0. Twenty-one patients underwent chemotherapy combined with local treatment, surgery and/or radiation therapy, and 22 underwent chemotherapy only. The median follow up was 7 months (range 3–28 months). The 1 and 2-years Progression Free Survival was 65 and 10 % for combined treatment and 22 and 0 % for chemotherapy alone (p < 0.01). The 1 and 2-years overall survival was 69 and 29 % for combined and 26 and 0 % for chemotherapy alone (p < 0.01). No toxicity greater than grade 2 was recorded. These data showed that in glioblastoma recurrence the combination of several approaches in a limited group of patients is more effective than a single treatment alone. This stress the importance of multimodality treatment whenever clinically feasible

  16. Numerical modeling of local scour around hydraulic structure in sandy beds by dynamic mesh method

    Science.gov (United States)

    Fan, Fei; Liang, Bingchen; Bai, Yuchuan; Zhu, Zhixia; Zhu, Yanjun

    2017-10-01

    Local scour, a non-negligible factor in hydraulic engineering, endangers the safety of hydraulic structures. In this work, a numerical model for simulating local scour was constructed, based on the open source code computational fluid dynamics model OpenFOAM. We consider both the bedload and suspended load sediment transport in the scour model and adopt the dynamic mesh method to simulate the evolution of the bed elevation. We use the finite area method to project data between the three-dimensional flow model and the two-dimensional (2D) scour model. We also improved the 2D sand slide method and added it to the scour model to correct the bed bathymetry when the bed slope angle exceeds the angle of repose. Moreover, to validate our scour model, we conducted and compared the results of three experiments with those of the developed model. The validation results show that our developed model can reliably simulate local scour.

  17. A Quantitative Method for Localizing User Interface Problems: The D-TEO Method

    Directory of Open Access Journals (Sweden)

    Juha Lamminen

    2009-01-01

    Full Text Available A large array of evaluation methods have been proposed to identify Website usability problems. In log-based evaluation, information about the performance of users is collected and stored into log files, and used to find problems and deficiencies in Web page designs. Most methods require the programming and modeling of large task models, which are cumbersome processes for evaluators. Also, because much statistical data is collected onto log files, recognizing which Web pages require deeper usability analysis is difficult. This paper suggests a novel quantitative method, called the D-TEO, for locating problematic Web pages. This semiautomated method explores the decomposition of interaction tasks of directed information search into elementary operations, deploying two quantitative usability criteria, search success and search time, to reveal how a user navigates within a web of hypertext.

  18. A Fuzzy Adaptive Tightly-Coupled Integration Method for Mobile Target Localization Using SINS/WSN

    Directory of Open Access Journals (Sweden)

    Wei Li

    2016-11-01

    Full Text Available In recent years, mobile target localization for enclosed environments has been a growing interest. In this paper, we have proposed a fuzzy adaptive tightly-coupled integration (FATCI method for positioning and tracking applications using strapdown inertial navigation system (SINS and wireless sensor network (WSN. The wireless signal outage and severe multipath propagation of WSN often influence the accuracy of measured distance and lead to difficulties with the WSN positioning. Note also that the SINS are known for their drifted error over time. Using as a base the well-known loosely-coupled integration method, we have built a tightly-coupled integrated positioning system for SINS/WSN based on the measured distances between anchor nodes and mobile node. The measured distance value of WSN is corrected with a least squares regression (LSR algorithm, with the aim of decreasing the systematic error for measured distance. Additionally, the statistical covariance of measured distance value is used to adjust the observation covariance matrix of a Kalman filter using a fuzzy inference system (FIS, based on the statistical characteristics. Then the tightly-coupled integration model can adaptively adjust the confidence level for measurement according to the different measured accuracies of distance measurements. Hence the FATCI system is achieved using SINS/WSN. This innovative approach is verified in real scenarios. Experimental results show that the proposed positioning system has better accuracy and stability compared with the loosely-coupled and traditional tightly-coupled integration model for WSN short-term failure or normal conditions.

  19. Unsupervised versus Supervised Identification of Prognostic Factors in Patients with Localized Retroperitoneal Sarcoma: A Data Clustering and Mahalanobis Distance Approach

    Directory of Open Access Journals (Sweden)

    Rita De Sanctis

    2018-01-01

    Full Text Available The aim of this report is to unveil specific prognostic factors for retroperitoneal sarcoma (RPS patients by univariate and multivariate statistical techniques. A phase I-II study on localized RPS treated with high-dose ifosfamide and radiotherapy followed by surgery (ISG-STS 0303 protocol demonstrated that chemo/radiotherapy was safe and increased the 3-year relapse-free survival (RFS with respect to historical controls. Of 70 patients, twenty-six developed local, 10 distant, and 5 combined relapse. Median disease-free interval (DFI was 29.47 months. According to a discriminant function analysis, DFI, histology, relapse pattern, and the first treatment approach at relapse had a statistically significant prognostic impact. Based on scientific literature and clinical expertise, clinicopathological data were analyzed using both a supervised and an unsupervised classification method to predict the prognosis, with similar sample sizes (66 and 65, resp., in casewise approach and 70 in mean-substitution one. This is the first attempt to predict patients’ prognosis by means of multivariate statistics, and in this light, it looks noticable that (i some clinical data have a well-defined prognostic value, (ii the unsupervised model produced comparable results with respect to the supervised one, and (iii the appropriate combination of both models appears fruitful and easily extensible to different clinical contexts.

  20. A Reference Point Construction Method Using Mobile Terminals and the Indoor Localization Evaluation in the Centroid Method

    Directory of Open Access Journals (Sweden)

    Takahiro Yamaguchi

    2015-05-01

    Full Text Available As smartphones become widespread, a variety of smartphone applications are being developed. This paper proposes a method for indoor localization (i.e., positioning that uses only smartphones, which are general-purpose mobile terminals, as reference point devices. This method has the following features: (a the localization system is built with smartphones whose movements are confined to respective limited areas. No fixed reference point devices are used; (b the method does not depend on the wireless performance of smartphones and does not require information about the propagation characteristics of the radio waves sent from reference point devices, and (c the method determines the location at the application layer, at which location information can be easily incorporated into high-level services. We have evaluated the level of localization accuracy of the proposed method by building a software emulator that modeled an underground shopping mall. We have confirmed that the determined location is within a small area in which the user can find target objects visually.

  1. What is new in the local approach of limb sarcomas and desmoid tumours?

    International Nuclear Information System (INIS)

    Bonvalot, S.; Rimareix, F.; Paumier, A.; Roberti, E.; Bouzaiene, H.; Le Pechoux, C.

    2010-01-01

    The treatment of soft tissue sarcomas of limbs should be discussed within an experienced multimodality team. Surgical resection remains the cornerstone of therapy for localized disease and achieves a five years overall survival around 75% and a local recurrence rate as low as 10% in the best series. In complex cases, neo-adjuvant treatments may be used such as systemic chemotherapy, isolated limb perfusion, or radiotherapy to achieve an optimal conservative approach. Molecular genetics of sarcomas and quality of margins are essential to guide diagnosis and therapeutic selection. In case of marginal or incomplete resection, a new enlarged surgical resection should always be discussed before administration of any adjuvant treatments. Many retrospective studies and two randomized studies (one of adjuvant brachytherapy and one of external beam radiotherapy) have shown that adjuvant radiotherapy after complete surgery significantly reduces the risk of local recurrence in extremity soft tissue sarcomas. A randomized study has compared pre- to postoperative radiotherapy. The results in terms of local control are similar in both arms. The risk of surgical complications is higher in the preoperative arm and the risk of late sequelae is higher in the postoperative arm. A randomized study within the French sarcoma group is ongoing evaluating the omission of postoperative radiotherapy in favourable cases. Presently, the role of systematic first-line invasive treatment (including surgery and/or radiotherapy) of desmoids is debated. It is becoming evident that up to 50% of patients with desmoids benefit from a front-line non-aggressive policy, because growth arrest is a common feature of this disease. Additional study of the molecular determinants of desmoid behaviour is needed to guide treatment. (authors)

  2. Using Online Dialogues to Connect Local Leaders and Climate Experts: Methods, Feedback and Lessons Learned from the Resilience Dialogues

    Science.gov (United States)

    Goodwin, M.; Pandya, R.; Weaver, C. P.; Zerbonne, S.; Bennett, N.; Spangler, B.

    2017-12-01

    Inclusive, multi-stakeholder dialogue, participatory planning and actionable science are necessary for just and effective climate resilience outcomes. How can we support that in practice? The Resilience Dialogues launched a public Beta in 2016-2017 to allow scientists and resilience practitioners to engage with local leaders from 10 communities around the US through a series of facilitated, online dialogues. We developed two, one-week dialogues for each community: one to consider ways to respond to observed and anticipated climate impacts through a resilience lens, and one to identify next steps and resources to advance key priorities. We divided the communities into three cohorts and refined the structure and facilitation strategy for these dialogues from one to the next based on participant feedback. This adaptive method helped participants engage in the dialogues more effectively and develop useful results. We distributed a survey to all participants following each cohort to capture feedback on the use and utility of the dialogues. While there was room for improvement in the program's technical interface, survey participants valued the dialogues and the opportunity to engage as equals. Local leaders said the dialogues helped identify new local pathways to approach resilience priorities. They felt they benefited from focused conversation and personalized introductions to best-matched resources. Practitioners learned how local leaders seek to apply climate science, and how to effectively communicate their expertise to community leaders in support of local planning efforts. We learned there is demand for specialized dialogues on issues like communication, financing and extreme weather. Overall, the desire of participants to continue to engage through this program, and others to enter, indicates that facilitated, open conversations between experts and local leaders can break down communication and access barriers between climate services providers and end

  3. Estimation of effective brain connectivity with dual Kalman filter and EEG source localization methods.

    Science.gov (United States)

    Rajabioun, Mehdi; Nasrabadi, Ali Motie; Shamsollahi, Mohammad Bagher

    2017-09-01

    Effective connectivity is one of the most important considerations in brain functional mapping via EEG. It demonstrates the effects of a particular active brain region on others. In this paper, a new method is proposed which is based on dual Kalman filter. In this method, firstly by using a brain active localization method (standardized low resolution brain electromagnetic tomography) and applying it to EEG signal, active regions are extracted, and appropriate time model (multivariate autoregressive model) is fitted to extracted brain active sources for evaluating the activity and time dependence between sources. Then, dual Kalman filter is used to estimate model parameters or effective connectivity between active regions. The advantage of this method is the estimation of different brain parts activity simultaneously with the calculation of effective connectivity between active regions. By combining dual Kalman filter with brain source localization methods, in addition to the connectivity estimation between parts, source activity is updated during the time. The proposed method performance has been evaluated firstly by applying it to simulated EEG signals with interacting connectivity simulation between active parts. Noisy simulated signals with different signal to noise ratios are used for evaluating method sensitivity to noise and comparing proposed method performance with other methods. Then the method is applied to real signals and the estimation error during a sweeping window is calculated. By comparing proposed method results in different simulation (simulated and real signals), proposed method gives acceptable results with least mean square error in noisy or real conditions.

  4. Approaches and Methods of Periodization in Literary History

    Directory of Open Access Journals (Sweden)

    Naser Gholi Sarli

    2013-10-01

    Full Text Available Abstract One of the most fundamental acts of historiography is to classify historical information in diachronic axis. The method of this classification or periodization shows the theoretical approach of the historian and determines the structure and the form of his history. Because of multiple criteria of analysis and various literary genres, periodization in literary history is more complicated than that of general history. We can distinguish two approaches in periodization of literary history, although these can be used together: extrinsic or social-cultural approach (based on criteria extrinsic to literature and intrinsic or formalist approach (based on criteria intrinsic to literature. Then periodization in literary history can be formulated in different methods and may be based upon various criteria: chronological such as century, decade and year organic patterns of evolution great poets and writers literary emblems and evaluations of every period events, concepts and periods of general or political history analogy of literary history and history of ideas or history of arts approaches and styles of language dominant literary norms. These methods actually are used together and everyone has adequacy in special kind of literary history. In periodization of Persian contemporary literature, some methods and models current in periodization of poetry have been applied identically to periodization of prose. Periodization based upon century, decade and year is the simplest and most mechanical method but sometimes certain centuries in some countries have symbolic and stylistic meaning, and decades were used often for subdivisions of literary history, especially nowadays with fast rhythm of literary change. Periodization according to organic patterns of evolution equates the changes of literary history with the life phases of an organism, and offers an account of birth, mature and death (and sometimes re-birth of literary genres, but this method have

  5. Approaches and Methods of Periodization in Literary History

    Directory of Open Access Journals (Sweden)

    Dr. N. Gh. Sarli

    Full Text Available One of the most fundamental acts of historiography is to classify historical information in diachronic axis. The method of this classification or periodization shows the theoretical approach of the historian and determines the structure and the form of his history. Because of multiple criteria of analysis and various literary genres, periodization in literary history is more complicated than that of general history. We can distinguish two approaches in periodization of literary history, although these can be used together: extrinsic or social-cultural approach (based on criteria extrinsic to literature and intrinsic or formalist approach (based on criteria intrinsic to literature. Then periodization in literary history can be formulated in different methods and may be based upon various criteria: chronological such as century, decade and year; organic patterns of evolution; great poets and writers; literary emblems and evaluations of every period; events, concepts and periods of general or political history; analogy of literary history and history of ideas or history of arts; approaches and styles of language; dominant literary norms. These methods actually are used together and everyone has adequacy in special kind of literary history. In periodization of Persian contemporary literature, some methods and models current in periodization of poetry have been applied identically to periodization of prose. Periodization based upon century, decade and year is the simplest and most mechanical method but sometimes certain centuries in some countries have symbolic and stylistic meaning, and decades were used often for subdivisions of literary history, especially nowadays with fast rhythm of literary change.Periodization according to organic patterns of evolution equates the changes of literary history with the life phases of an organism, and offers an account of birth, mature and death (and sometimes re-birth of literary genres, but this method have

  6. Approaches and Methods of Periodization in Literary History

    Directory of Open Access Journals (Sweden)

    Naser Gholi Sarli

    2013-11-01

    Full Text Available Abstract One of the most fundamental acts of historiography is to classify historical information in diachronic axis. The method of this classification or periodization shows the theoretical approach of the historian and determines the structure and the form of his history. Because of multiple criteria of analysis and various literary genres, periodization in literary history is more complicated than that of general history. We can distinguish two approaches in periodization of literary history, although these can be used together: extrinsic or social-cultural approach (based on criteria extrinsic to literature and intrinsic or formalist approach (based on criteria intrinsic to literature. Then periodization in literary history can be formulated in different methods and may be based upon various criteria: chronological such as century, decade and year organic patterns of evolution great poets and writers literary emblems and evaluations of every period events, concepts and periods of general or political history analogy of literary history and history of ideas or history of arts approaches and styles of language dominant literary norms. These methods actually are used together and everyone has adequacy in special kind of literary history. In periodization of Persian contemporary literature, some methods and models current in periodization of poetry have been applied identically to periodization of prose. Periodization based upon century, decade and year is the simplest and most mechanical method but sometimes certain centuries in some countries have symbolic and stylistic meaning, and decades were used often for subdivisions of literary history, especially nowadays with fast rhythm of literary change. Periodization according to organic patterns of evolution equates the changes of literary history with the life phases of an organism, and offers an account of birth, mature and death (and sometimes re-birth of literary genres, but this method have

  7. A statistical-dynamical modeling approach for the simulation of local paleo proxy records using GCM output

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, B.K.; Bengtsson, L. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Aakesson, O. [Sveriges Meteorologiska och Hydrologiska Inst., Norrkoeping (Sweden)

    1998-08-01

    Recent proxy data obtained from ice core measurements, dendrochronology and valley glaciers provide important information on the evolution of the regional or local climate. General circulation models integrated over a long period of time could help to understand the (external and internal) forcing mechanisms of natural climate variability. For a systematic interpretation of in situ paleo proxy records, a combined method of dynamical and statistical modeling is proposed. Local 'paleo records' can be simulated from GCM output by first undertaking a model-consistent statistical downscaling and then using a process-based forward modeling approach to obtain the behavior of valley glaciers and the growth of trees under specific conditions. The simulated records can be compared to actual proxy records in order to investigate whether e.g. the response of glaciers to climatic change can be reproduced by models and to what extent climate variability obtained from proxy records (with the main focus on the last millennium) can be represented. For statistical downscaling to local weather conditions, a multiple linear forward regression model is used. Daily sets of observed weather station data and various large-scale predictors at 7 pressure levels obtained from ECMWF reanalyses are used for development of the model. Daily data give the closest and most robust relationships due to the strong dependence on individual synoptic-scale patterns. For some local variables, the performance of the model can be further increased by developing seasonal specific statistical relationships. The model is validated using both independent and restricted predictor data sets. The model is applied to a long integration of a mixed layer GCM experiment simulating pre-industrial climate variability. The dynamical-statistical local GCM output within a region around Nigardsbreen glacier, Norway is compared to nearby observed station data for the period 1868-1993. Patterns of observed

  8. A Hidden Markov Model Approach for Simultaneously Estimating Local Ancestry and Admixture Time Using Next Generation Sequence Data in Samples of Arbitrary Ploidy.

    Science.gov (United States)

    Corbett-Detig, Russell; Nielsen, Rasmus

    2017-01-01

    Admixture-the mixing of genomes from divergent populations-is increasingly appreciated as a central process in evolution. To characterize and quantify patterns of admixture across the genome, a number of methods have been developed for local ancestry inference. However, existing approaches have a number of shortcomings. First, all local ancestry inference methods require some prior assumption about the expected ancestry tract lengths. Second, existing methods generally require genotypes, which is not feasible to obtain for many next-generation sequencing projects. Third, many methods assume samples are diploid, however a wide variety of sequencing applications will fail to meet this assumption. To address these issues, we introduce a novel hidden Markov model for estimating local ancestry that models the read pileup data, rather than genotypes, is generalized to arbitrary ploidy, and can estimate the time since admixture during local ancestry inference. We demonstrate that our method can simultaneously estimate the time since admixture and local ancestry with good accuracy, and that it performs well on samples of high ploidy-i.e. 100 or more chromosomes. As this method is very general, we expect it will be useful for local ancestry inference in a wider variety of populations than what previously has been possible. We then applied our method to pooled sequencing data derived from populations of Drosophila melanogaster on an ancestry cline on the east coast of North America. We find that regions of local recombination rates are negatively correlated with the proportion of African ancestry, suggesting that selection against foreign ancestry is the least efficient in low recombination regions. Finally we show that clinal outlier loci are enriched for genes associated with gene regulatory functions, consistent with a role of regulatory evolution in ecological adaptation of admixed D. melanogaster populations. Our results illustrate the potential of local ancestry

  9. Calculation methods' comparative analysis of monorail hoist crane local bending effects

    Directory of Open Access Journals (Sweden)

    Cvijović Goran M.

    2016-01-01

    Full Text Available The results of numerical and experimental researches of local bending problems, carried on classic and medium-wide I profiles, were a basis for the adoption of the current standards (EN 15011: 2014 which regulates the action of the local stress caused by the effect of cart wheels. Regarding the fact that IPB (HE-B wide flange profiles are largely used for production of the main carriers of monorail transport systems, this paper presents the results of the action of the local stress caused by the effect of cart wheels on the HE-A flange profile, using the methods and procedures of relevant researchers, the procedures prescribed by the standard EN 15011 as well as the results of calculations using finite element method. It has been revealed, based on comparative analysis of the results, that in the transition zone low flange / rib longitudinal local stress on the lower contour flange, determined using the above mentioned standards have tightening characteristic, while all other methods, including finite element method, give the pressing nature of the considered voltage. In addition, all of these procedures, except for the finite element method, adopt the assumption that absolute value of voltage, caused by local bending on upper and lower contour of the loaded flange, are the same, and there is no physical justification. Bearing in mind the fact that stress identification, caused by the flange local bending, is an extremely important phase proving the strength of monorail beams, we may conclude that the application of standard EN 15011 does not provide reliable results when it comes to wide flange profiles.

  10. Local region power spectrum-based unfocused ship detection method in synthetic aperture radar images

    Science.gov (United States)

    Wei, Xiangfei; Wang, Xiaoqing; Chong, Jinsong

    2018-01-01

    Ships on synthetic aperture radar (SAR) images will be severely defocused and their energy will disperse into numerous resolution cells under long SAR integration time. Therefore, the image intensity of ships is weak and sometimes even overwhelmed by sea clutter on SAR image. Consequently, it is hard to detect the ships from SAR intensity images. A ship detection method based on local region power spectrum of SAR complex image is proposed. Although the energies of the ships are dispersed on SAR intensity images, their spectral energies are rather concentrated or will cause the power spectra of local areas of SAR images to deviate from that of sea surface background. Therefore, the key idea of the proposed method is to detect ships via the power spectra distortion of local areas of SAR images. The local region power spectrum of a moving target on SAR image is analyzed and the way to obtain the detection threshold through the probability density function (pdf) of the power spectrum is illustrated. Numerical P- and L-band airborne SAR ocean data are utilized and the detection results are also illustrated. Results show that the proposed method can well detect the unfocused ships, with a detection rate of 93.6% and a false-alarm rate of 8.6%. Moreover, by comparing with some other algorithms, it indicates that the proposed method performs better under long SAR integration time. Finally, the applicability of the proposed method and the way of parameters selection are also discussed.

  11. Basis set approach in the constrained interpolation profile method

    International Nuclear Information System (INIS)

    Utsumi, T.; Koga, J.; Yabe, T.; Ogata, Y.; Matsunaga, E.; Aoki, T.; Sekine, M.

    2003-07-01

    We propose a simple polynomial basis-set that is easily extendable to any desired higher-order accuracy. This method is based on the Constrained Interpolation Profile (CIP) method and the profile is chosen so that the subgrid scale solution approaches the real solution by the constraints from the spatial derivative of the original equation. Thus the solution even on the subgrid scale becomes consistent with the master equation. By increasing the order of the polynomial, this solution quickly converges. 3rd and 5th order polynomials are tested on the one-dimensional Schroedinger equation and are proved to give solutions a few orders of magnitude higher in accuracy than conventional methods for lower-lying eigenstates. (author)

  12. Ethics, Collaboration, and Presentation Methods for Local and Traditional Knowledge for Understanding Arctic Change

    Science.gov (United States)

    Parsons, M. A.; Gearheard, S.; McNeave, C.

    2009-12-01

    Local and traditional knowledge (LTK) provides rich information about the Arctic environment at spatial and temporal scales that scientific knowledge often does not have access to (e.g. localized observations of fine-scale ecological change potentially from many different communities, or local sea ice and conditions prior to 1950s ice charts and 1970s satellite records). Community-based observations and monitoring are an opportunity for Arctic residents to provide ‘frontline’ observations and measurements that are an early warning system for Arctic change. The Exchange for Local Observations and Knowledge of the Arctic (ELOKA) was established in response to the growing number of community-based and community-oriented research and observation projects in the Arctic. ELOKA provides data management and user support to facilitate the collection, preservation, exchange, and use of local observations and knowledge. Managing these data presents unique ethical challenges in terms of appropriate use of rare human knowledge and ensuring that knowledge is not lost from the local communities and not exploited in ways antithetical to community culture and desires. Local Arctic residents must be engaged as true collaborative partners while respecting their perspectives, which may vary substantially from a western science perspective. At the same time, we seek to derive scientific meaning from the local knowledge that can be used in conjunction with quantitative science data. This creates new challenges in terms of data presentation, knowledge representations, and basic issues of metadata. This presentation reviews these challenges, some initial approaches to addressing them, and overall lessons learned and future directions.

  13. Research on vibration signal analysis and extraction method of gear local fault

    Science.gov (United States)

    Yang, X. F.; Wang, D.; Ma, J. F.; Shao, W.

    2018-02-01

    Gear is the main connection parts and power transmission parts in the mechanical equipment. If the fault occurs, it directly affects the running state of the whole machine and even endangers the personal safety. So it has important theoretical significance and practical value to study on the extraction of the gear fault signal and fault diagnosis of the gear. In this paper, the gear local fault as the research object, set up the vibration model of gear fault vibration mechanism, derive the vibration mechanism of the gear local fault and analyzes the similarities and differences of the vibration signal between the gear non fault and the gears local faults. In the MATLAB environment, the wavelet transform algorithm is used to denoise the fault signal. Hilbert transform is used to demodulate the fault vibration signal. The results show that the method can denoise the strong noise mechanical vibration signal and extract the local fault feature information from the fault vibration signal..

  14. The Rate-Controlled Constrained-Equilibrium Approach to Far-From-Local-Equilibrium Thermodynamics

    Directory of Open Access Journals (Sweden)

    Hameed Metghalchi

    2012-01-01

    Full Text Available The Rate-Controlled Constrained-Equilibrium (RCCE method for the description of the time-dependent behavior of dynamical systems in non-equilibrium states is a general, effective, physically based method for model order reduction that was originally developed in the framework of thermodynamics and chemical kinetics. A generalized mathematical formulation is presented here that allows including nonlinear constraints in non-local equilibrium systems characterized by the existence of a non-increasing Lyapunov functional under the system’s internal dynamics. The generalized formulation of RCCE enables to clarify the essentials of the method and the built-in general feature of thermodynamic consistency in the chemical kinetics context. In this paper, we work out the details of the method in a generalized mathematical-physics framework, but for definiteness we detail its well-known implementation in the traditional chemical kinetics framework. We detail proofs and spell out explicit functional dependences so as to bring out and clarify each underlying assumption of the method. In the standard context of chemical kinetics of ideal gas mixtures, we discuss the relations between the validity of the detailed balance condition off-equilibrium and the thermodynamic consistency of the method. We also discuss two examples of RCCE gas-phase combustion calculations to emphasize the constraint-dependent performance of the RCCE method.

  15. Hybrid Genetic Algorithm - Local Search Method for Ground-Water Management

    Science.gov (United States)

    Chiu, Y.; Nishikawa, T.; Martin, P.

    2008-12-01

    Ground-water management problems commonly are formulated as a mixed-integer, non-linear programming problem (MINLP). Relying only on conventional gradient-search methods to solve the management problem is computationally fast; however, the methods may become trapped in a local optimum. Global-optimization schemes can identify the global optimum, but the convergence is very slow when the optimal solution approaches the global optimum. In this study, we developed a hybrid optimization scheme, which includes a genetic algorithm and a gradient-search method, to solve the MINLP. The genetic algorithm identifies a near- optimal solution, and the gradient search uses the near optimum to identify the global optimum. Our methodology is applied to a conjunctive-use project in the Warren ground-water basin, California. Hi- Desert Water District (HDWD), the primary water-manager in the basin, plans to construct a wastewater treatment plant to reduce future septic-tank effluent from reaching the ground-water system. The treated wastewater instead will recharge the ground-water basin via percolation ponds as part of a larger conjunctive-use strategy, subject to State regulations (e.g. minimum distances and travel times). HDWD wishes to identify the least-cost conjunctive-use strategies that control ground-water levels, meet regulations, and identify new production-well locations. As formulated, the MINLP objective is to minimize water-delivery costs subject to constraints including pump capacities, available recharge water, water-supply demand, water-level constraints, and potential new-well locations. The methodology was demonstrated by an enumerative search of the entire feasible solution and comparing the optimum solution with results from the branch-and-bound algorithm. The results also indicate that the hybrid method identifies the global optimum within an affordable computation time. Sensitivity analyses, which include testing different recharge-rate scenarios, pond

  16. Comparison between continuous and localized methods to evaluate the flow rate through containment concrete structures

    Energy Technology Data Exchange (ETDEWEB)

    Jason, L., E-mail: ludovic.jason@cea.fr [Atomic Energy Commission (CEA), DEN, DANS, DM2S, SEMT, Mechanics and System Simulation Laboratory (LM2S), F-91191 Gif sur Yvette (France); LaMSID, UMR CNRS-EDF-CEA 8193, F-92141 Clamart (France); Masson, B. [Electricité de France (EDF), SEPTEN, F-69628 Villeurbanne (France)

    2014-10-01

    Highlights: • The contribution focuses on the gas transfer through reinforced concrete structures. • A continuous approach with a damage–permeability law is investigated. • It is significant, for this case, only when the damage variable crosses the section. • In this case, two localized approaches are compared. • It helps at evaluating a “reference” crack opening for engineering laws. - Abstract: In this contribution, different techniques are compared to evaluate the gas flow rate through a representative section of a reinforced and prestressed concrete containment structure. A continuous approach is first applied which is based on the evaluation of the gas permeability as a function of the damage variable. The calculations show that the flow rate becomes significant only when the damage variable crosses the section. But in this situation, the continuous approach is no longer fully valid. That is why localized approaches, based on a fine description of the crack openings, are then investigated. A comparison between classical simplified laws (Poiseuille flow) and a more refined model which takes into account the evolution of the crack opening in the depth of the section enables to define the validity domain of the simplified laws and especially the definition of the associated “reference opening”.

  17. The Local Maximum Clustering Method and Its Application in Microarray Gene Expression Data Analysis

    Directory of Open Access Journals (Sweden)

    Chen Yidong

    2004-01-01

    Full Text Available An unsupervised data clustering method, called the local maximum clustering (LMC method, is proposed for identifying clusters in experiment data sets based on research interest. A magnitude property is defined according to research purposes, and data sets are clustered around each local maximum of the magnitude property. By properly defining a magnitude property, this method can overcome many difficulties in microarray data clustering such as reduced projection in similarities, noises, and arbitrary gene distribution. To critically evaluate the performance of this clustering method in comparison with other methods, we designed three model data sets with known cluster distributions and applied the LMC method as well as the hierarchic clustering method, the -mean clustering method, and the self-organized map method to these model data sets. The results show that the LMC method produces the most accurate clustering results. As an example of application, we applied the method to cluster the leukemia samples reported in the microarray study of Golub et al. (1999.

  18. A coarse-to-fine approach for pericardial effusion localization and segmentation in chest CT scans

    Science.gov (United States)

    Liu, Jiamin; Chellamuthu, Karthik; Lu, Le; Bagheri, Mohammadhadi; Summers, Ronald M.

    2018-02-01

    Pericardial effusion on CT scans demonstrates very high shape and volume variability and very low contrast to adjacent structures. This inhibits traditional automated segmentation methods from achieving high accuracies. Deep neural networks have been widely used for image segmentation in CT scans. In this work, we present a two-stage method for pericardial effusion localization and segmentation. For the first step, we localize the pericardial area from the entire CT volume, providing a reliable bounding box for the more refined segmentation step. A coarse-scaled holistically-nested convolutional networks (HNN) model is trained on entire CT volume. The resulting HNN per-pixel probability maps are then threshold to produce a bounding box covering the pericardial area. For the second step, a fine-scaled HNN model is trained only on the bounding box region for effusion segmentation to reduce the background distraction. Quantitative evaluation is performed on a dataset of 25 CT scans of patient (1206 images) with pericardial effusion. The segmentation accuracy of our two-stage method, measured by Dice Similarity Coefficient (DSC), is 75.59+/-12.04%, which is significantly better than the segmentation accuracy (62.74+/-15.20%) of only using the coarse-scaled HNN model.

  19. The Rise and Attenuation of the Basic Education Programme (BEP) in Botswana: A Global-Local Dialectic Approach

    Science.gov (United States)

    Tabulawa, Richard

    2011-01-01

    Using a global-local dialectic approach, this paper traces the rise of the basic education programme in the 1980s and 1990s in Botswana and its subsequent attenuation in the 2000s. Amongst the local forces that led to the rise of BEP were Botswana's political project of nation-building; the country's dire human resources situation in the decades…

  20. Creative Approaches to Teaching Graduate Research Methods Workshops

    Directory of Open Access Journals (Sweden)

    Peter Reilly

    2017-06-01

    Full Text Available Engagement and deeper learning were enhanced by developing several innovative teaching strategies delivered in Research Methods workshops to Graduate Business Students.  Focusing primarily on students adopting a creative approach to formulating a valid research question for undertaking a dissertation successfully. These techniques are applicable to most subject domains to ensure student engagement.  Addressing the various multiple intelligences and learning styles existing within groups while ensuring these sessions are student centred and conducive to a collaborative learning environment.  Blogs, interactive tutorials, online videos, games and posters, are used to develop student’s cognitive and metacognitive abilities.  Using novelty images appeals to a groups’ intellectual curiosity, acting as an interpretive device to explain  the value of adopting a holistic rather than analytic approach towards a topic.

  1. Methods for measuring denitrification: Diverse approaches to a difficult problem

    DEFF Research Database (Denmark)

    Groffman, Peter M.; Altabet, Mark A.; Böhlke, J. K.

    2006-01-01

    , and global scales. Unfortunately, this process is very difficult to measure, and existing methods are problematic for different reasons in different places at different times. In this paper, we review the major approaches that have been taken to measure denitrification in terrestrial and aquatic environments...... based on stable isotopes, (8) in situ gradients with atmospheric environmental tracers, and (9) molecular approaches. Our review makes it clear that the prospects for improved quantification of denitrification vary greatly in different environments and at different scales. While current methodology allows...... for the production of accurate estimates of denitrification at scales relevant to water and air quality and ecosystem fertility questions in some systems (e.g., aquatic sediments, well-defined aquifers), methodology for other systems, especially upland terrestrial areas, still needs development. Comparison of mass...

  2. A finite volume method for cylindrical heat conduction problems based on local analytical solution

    KAUST Repository

    Li, Wang

    2012-10-01

    A new finite volume method for cylindrical heat conduction problems based on local analytical solution is proposed in this paper with detailed derivation. The calculation results of this new method are compared with the traditional second-order finite volume method. The newly proposed method is more accurate than conventional ones, even though the discretized expression of this proposed method is slightly more complex than the second-order central finite volume method, making it cost more calculation time on the same grids. Numerical result shows that the total CPU time of the new method is significantly less than conventional methods for achieving the same level of accuracy. © 2012 Elsevier Ltd. All rights reserved.

  3. A finite volume method for cylindrical heat conduction problems based on local analytical solution

    KAUST Repository

    Li, Wang; Yu, Bo; Wang, Xinran; Wang, Peng; Sun, Shuyu

    2012-01-01

    A new finite volume method for cylindrical heat conduction problems based on local analytical solution is proposed in this paper with detailed derivation. The calculation results of this new method are compared with the traditional second-order finite volume method. The newly proposed method is more accurate than conventional ones, even though the discretized expression of this proposed method is slightly more complex than the second-order central finite volume method, making it cost more calculation time on the same grids. Numerical result shows that the total CPU time of the new method is significantly less than conventional methods for achieving the same level of accuracy. © 2012 Elsevier Ltd. All rights reserved.

  4. A new approach to self-localization for mobile robots using sensor data fusion

    International Nuclear Information System (INIS)

    Moshiri, B.; Asharif, M.; Hoseim Nezhad, R.

    2002-01-01

    This paper proposes a new approach for calibration of dead reckoning process. Using the well-known UMB mark (University of Michigan Benchmark) is not sufficient for a desirable calibration of dead reckoning. Besides, existing calibration methods usually require explicit measurement of actual motion of the robot. Some recent methods use the smart encoder trailer or long range finder sensors such as ultrasonic or laser range finders for automatic calibration. Manual measurement is necessary in the case of the robots that are not equipped with long-range detectors or such smart encoder trailer. Our proposed approach uses an environment map that is created by fusion of proximity data, in order to calibrate the odometry error automatically. In the new approach, the systematic part of the error is adaptively estimated and compensated by an efficient and incremental maximum likelihood algorithm. Actually, environment map data are fused with the odometry and current sensory data in order to acquire the maximum likelihood estimation. The advantages of the proposed approach are demonstrated in some experiments with Khepera robot. It is shown that the amount of pose estimation error is reduced by a percentage of more than 80%

  5. Improved open-sun drying method for local swamp rice in Uganda ...

    African Journals Online (AJOL)

    “Kaiso” and “Supa” are the main local swamp-rice (Oryza Sativa) varieties currently grown in Uganda mainly by smallholder farmers on small gardens (0.5 – 2ha). Due to lack of mechanized drying equipment and owing to the low volumes of their harvests, these farmers use open-sun drying methods, where the paddy is ...

  6. Localization of Simultaneous Moving Sound Sources for Mobile Robot Using a Frequency-Domain Steered Beamformer Approach

    OpenAIRE

    Valin, Jean-Marc; Michaud, François; Hadjou, Brahim; Rouat, Jean

    2016-01-01

    Mobile robots in real-life settings would benefit from being able to localize sound sources. Such a capability can nicely complement vision to help localize a person or an interesting event in the environment, and also to provide enhanced processing for other capabilities such as speech recognition. In this paper we present a robust sound source localization method in three-dimensional space using an array of 8 microphones. The method is based on a frequency-domain implementation of a steered...

  7. Methodical Approaches to Communicative Providing of Retailer Branding

    Directory of Open Access Journals (Sweden)

    Andrey Kataev

    2017-07-01

    Full Text Available The thesis is devoted to the rationalization of methodical approaches for provision of branding of retail trade enterprises. The article considers the features of brand perception by retail consumers and clarifies the specifics of customer reviews of stores for the procedures accompanying brand management. It is proved that besides traditional communication mix, the most important tool of communicative influence on buyers is the store itself as a place for comfortable shopping. The shop should have a stimulating effect on all five human senses, including sight, smell, hearing, touch, and taste, which shall help maximize consumer integration into the buying process.

  8. Reasoning methods in medical consultation systems: artificial intelligence approaches.

    Science.gov (United States)

    Shortliffe, E H

    1984-01-01

    It has been argued that the problem of medical diagnosis is fundamentally ill-structured, particularly during the early stages when the number of possible explanations for presenting complaints can be immense. This paper discusses the process of clinical hypothesis evocation, contrasts it with the structured decision making approaches used in traditional computer-based diagnostic systems, and briefly surveys the more open-ended reasoning methods that have been used in medical artificial intelligence (AI) programs. The additional complexity introduced when an advice system is designed to suggest management instead of (or in addition to) diagnosis is also emphasized. Example systems are discussed to illustrate the key concepts.

  9. An Exploration of Constructive Approach to the Higher Institutions’ MOOC with Chinese Local Characteristics

    Science.gov (United States)

    Liu, Yong

    2017-09-01

    Although the paradigm change led by MOOC in the field of higher education has many supporters, and MOOC has been applied widely for many years in the world. Now, more and more people begin to pay attention to the disputes about disadvantages and advantages of the MOOC. At first, the article indicates that some innate bad genes of MOOC, such as the cultural erosion tendency, the high drop out rate, the low effectiveness of the teaching evaluation and the low reliability of the course credits. And then the article faces the process of Chinese MOOC construction in different colleges and universities, and focuses on how to improve the innate bad genes of MOOC. Finally, the article gives some suggestions to explore a constructive approach to the higher institutions’ MOOC with Chinese local characteristics.

  10. Quantum group structure and local fields in the algebraic approach to 2D gravity

    Science.gov (United States)

    Schnittger, J.

    1995-07-01

    This review contains a summary of the work by J.-L. Gervais and the author on the operator approach to 2d gravity. Special emphasis is placed on the construction of local observables — the Liouville exponentials and the Liouville field itself — and the underlying algebra of chiral vertex operators. The double quantum group structure arising from the presence of two screening charges is discussed and the generalized algebra and field operators are derived. In the last part, we show that our construction gives rise to a natural definition of a quantum tau function, which is a noncommutative version of the classical group-theoretic representation of the Liouville fields by Leznov and Saveliev.

  11. FEM × DEM: a new efficient multi-scale approach for geotechnical problems with strain localization

    Directory of Open Access Journals (Sweden)

    Nguyen Trung Kien

    2017-01-01

    Full Text Available The paper presents a multi-scale modeling of Boundary Value Problem (BVP approach involving cohesive-frictional granular materials in the FEM × DEM multi-scale framework. On the DEM side, a 3D model is defined based on the interactions of spherical particles. This DEM model is built through a numerical homogenization process applied to a Volume Element (VE. It is then paired with a Finite Element code. Using this numerical tool that combines two scales within the same framework, we conducted simulations of biaxial and pressuremeter tests on a cohesive-frictional granular medium. In these cases, it is known that strain localization does occur at the macroscopic level, but since FEMs suffer from severe mesh dependency as soon as shear band starts to develop, the second gradient regularization technique has been used. As a consequence, the objectivity of the computation with respect to mesh dependency is restored.

  12. A state variable approach to the BESSY II local beam-position-feedback system

    International Nuclear Information System (INIS)

    Gilpatrick, J.D.; Khan, S.; Kraemer, D.

    1996-01-01

    At the BESSY II facility, stability of the electron beam position and angle near insertion devices (IDs) is of utmost importance. Disturbances due to ground motion could result in unwanted broad-bandwidth beam-jitter which decreases the electron (and resultant photon) beam's effective brightness. Therefore, feedback techniques must be used. Operating over a frequency range of 100-Hz, a local feedback system will correct these beam-trajectory errors using the four bumps around IDs. This paper reviews how the state-variable feedback approach can be applied to real-time correction of these beam position and angle errors. A frequency-domain solution showing beam jitter reduction is presented. Finally, this paper reports results of a beam-feedback test at BESSY I

  13. Integrative Approaches for the Identification and Localization of Specialized Metabolites in Tripterygium Roots1[OPEN

    Science.gov (United States)

    Fischedick, Justin T.; Lange, Malte F.; Poirier, Brenton C.

    2017-01-01

    Members of the genus Tripterygium are known to contain an astonishing diversity of specialized metabolites. The lack of authentic standards has been an impediment to the rapid identification of such metabolites in extracts. We employed an approach that involves the searching of multiple, complementary chromatographic and spectroscopic data sets against the Spektraris database to speed up the metabolite identification process. Mass spectrometry-based imaging indicated a differential localization of triterpenoids to the periderm and sesquiterpene alkaloids to the cortex layer of Tripterygium roots. We further provide evidence that triterpenoids are accumulated to high levels in cells that contain suberized cell walls, which might indicate a mechanism for storage. To our knowledge, our data provide first insights into the cell type specificity of metabolite accumulation in Tripterygium and set the stage for furthering our understanding of the biological implications of specialized metabolites in this genus. PMID:27864443

  14. [A new approach to clinical and laboratory diagnosis of systemic and local soft tissue infections].

    Science.gov (United States)

    Barkhatova, N A

    2009-01-01

    Dynamic measurements of blood TNF-a, IL-IRA, CRP, oligopeptide, and lactoferrin levels in patients with systemic and local soft tissue infections revealed direct correlation between them which allowed to use these indicators for the diagnosis of systemic infections. Results of clinical and laboratory analyses provided a basis for distinguishing short-term systemic inflammatory response syndrome and sepsis and developing relevant diagnostic criteria. Sepsis combined with systemic inflammatory response syndrome persisting for more than 72 hours after the onset of adequate therapy was characterized by CRP levels > 30 mg/l, oligopeptides > 0.34 U, lactoferrin > 1900 ng/ml, TNF-a > 6 pg/ml, ILL-IRA systemic inflammatory response syndrome for less than 72 hours had lower TNF-a, CRP, oligopeptide, and lactoferrin levels with IL-IRA > 1500 pg/ml. This new approach to early diagnosis of systemic infections makes it possible to optimize their treatment and thereby enhance its efficiency.

  15. A Voxel-Based Approach to Explore Local Dose Differences Associated With Radiation-Induced Lung Damage

    Energy Technology Data Exchange (ETDEWEB)

    Palma, Giuseppe [Institute of Biostructure and Bioimaging, National Research Council, Naples (Italy); Monti, Serena [IRCCS SDN, Naples (Italy); D' Avino, Vittoria [Institute of Biostructure and Bioimaging, National Research Council, Naples (Italy); Conson, Manuel [Institute of Biostructure and Bioimaging, National Research Council, Naples (Italy); Department of Advanced Biomedical Sciences, Federico II University School of Medicine, Naples (Italy); Liuzzi, Raffaele [Institute of Biostructure and Bioimaging, National Research Council, Naples (Italy); Pressello, Maria Cristina [Department of Health Physics, S. Camillo-Forlanini Hospital, Rome (Italy); Donato, Vittorio [Department of Radiation Oncology, S. Camillo-Forlanini Hospital, Rome (Italy); Deasy, Joseph O. [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY (United States); Quarantelli, Mario [Institute of Biostructure and Bioimaging, National Research Council, Naples (Italy); Pacelli, Roberto [Institute of Biostructure and Bioimaging, National Research Council, Naples (Italy); Department of Advanced Biomedical Sciences, Federico II University School of Medicine, Naples (Italy); Cella, Laura, E-mail: laura.cella@cnr.it [Institute of Biostructure and Bioimaging, National Research Council, Naples (Italy)

    2016-09-01

    Purpose: To apply a voxel-based (VB) approach aimed at exploring local dose differences associated with late radiation-induced lung damage (RILD). Methods and Materials: An interinstitutional database of 98 patients who were Hodgkin lymphoma (HL) survivors treated with postchemotherapy supradiaphragmatic radiation therapy was analyzed in the study. Eighteen patients experienced late RILD, classified according to the Radiation Therapy Oncology Group scoring system. Each patient's computed tomographic (CT) scan was normalized to a single reference case anatomy (common coordinate system, CCS) through a log-diffeomorphic approach. The obtained deformation fields were used to map the dose of each patient into the CCS. The coregistration robustness and the dose mapping accuracy were evaluated by geometric and dose scores. Two different statistical mapping schemes for nonparametric multiple permutation inference on dose maps were applied, and the corresponding P<.05 significance lung subregions were generated. A receiver operating characteristic (ROC)-based test was performed on the mean dose extracted from each subregion. Results: The coregistration process resulted in a geometrically robust and accurate dose warping. A significantly higher dose was consistently delivered to RILD patients in voxel clusters near the peripheral medial-basal portion of the lungs. The area under the ROC curves (AUC) from the mean dose of the voxel clusters was higher than the corresponding AUC derived from the total lung mean dose. Conclusions: We implemented a framework including a robust registration process and a VB approach accounting for the multiple comparison problem in dose-response modeling, and applied it to a cohort of HL survivors to explore a local dose–RILD relationship in the lungs. Patients with RILD received a significantly greater dose in parenchymal regions where low doses (∼6 Gy) were delivered. Interestingly, the relation between differences in the high

  16. Renormalization group-theoretic approach to electron localization in disordered systems

    International Nuclear Information System (INIS)

    Kumar, N.; Heinrichs, J.

    1977-06-01

    The localization problem for the Anderson tight-binding model with site-diagonal (gaussian) disorder is studied, using a previously established analogy between this problem and the statistical mechanics of a zero-component classical field. The equivalent free-energy functional turns out to have complex coefficients in the bilinear terms but involves a real repulsive quartic interaction. The averaged one-electron propagator corresponds to the two-point correlation function for the equivalent statistical problem and the critical point gives the mobility edge, which is identified with the (real) fixed point energy of the associated renormalization group. Since for convergence reasons the conventional perturbative treatment of Wilson's formula is invalid, it is resorted to a non-perturbative approach which leads to a physical fixed point corresponding to a repulsive quartic interaction. The results for the mobility edge in three dimensions and for the critical disorder for an Anderson transition in two dimensions agree well with previous detailed predictions. The critical indices describing the approach of the transition at the mobility edge of various physical quantities, within the epsilon-expansion are also discussed. The more general problem where both diagonal and off-diagonal disorder is present in the Anderson hamiltonian is considered. In this case it is shown that the Hamilton function for the equivalent zero-component classical field model involves an additional biquadratic exchange term. From a simple generalization of Wilson's recursion relation and its non-perturbative solution explicit expressions for the mobility edges for weak diagonal and off-diagonal disorder in two and three dimensions are obtained. Our treatment casts doubts on the validity of recent conclusions about electron localization based on the renormalization group study of the nm-component spin model

  17. SozRank: A new approach for localizing the epileptic seizure onset zone.

    Science.gov (United States)

    Murin, Yonathan; Kim, Jeremy; Parvizi, Josef; Goldsmith, Andrea

    2018-01-01

    Epilepsy is one of the most common neurological disorders affecting about 1% of the world population. For patients with focal seizures that cannot be treated with antiepileptic drugs, the common treatment is a surgical procedure for removal of the seizure onset zone (SOZ). In this work we introduce an algorithm for automatic localization of the seizure onset zone (SOZ) in epileptic patients based on electrocorticography (ECoG) recordings. The proposed algorithm builds upon the hypothesis that the abnormal excessive (or synchronous) neuronal activity in the brain leading to seizures starts in the SOZ and then spreads to other areas in the brain. Thus, when this abnormal activity starts, signals recorded at electrodes close to the SOZ should have a relatively large causal influence on the rest of the recorded signals. The SOZ localization is executed in two steps. First, the algorithm represents the set of electrodes using a directed graph in which nodes correspond to recording electrodes and the edges' weights quantify the pair-wise causal influence between the recorded signals. Then, the algorithm infers the SOZ from the estimated graph using a variant of the PageRank algorithm followed by a novel post-processing phase. Inference results for 19 patients show a close match between the SOZ inferred by the proposed approach and the SOZ estimated by expert neurologists (success rate of 17 out of 19).

  18. SozRank: A new approach for localizing the epileptic seizure onset zone.

    Directory of Open Access Journals (Sweden)

    Yonathan Murin

    2018-01-01

    Full Text Available Epilepsy is one of the most common neurological disorders affecting about 1% of the world population. For patients with focal seizures that cannot be treated with antiepileptic drugs, the common treatment is a surgical procedure for removal of the seizure onset zone (SOZ. In this work we introduce an algorithm for automatic localization of the seizure onset zone (SOZ in epileptic patients based on electrocorticography (ECoG recordings. The proposed algorithm builds upon the hypothesis that the abnormal excessive (or synchronous neuronal activity in the brain leading to seizures starts in the SOZ and then spreads to other areas in the brain. Thus, when this abnormal activity starts, signals recorded at electrodes close to the SOZ should have a relatively large causal influence on the rest of the recorded signals. The SOZ localization is executed in two steps. First, the algorithm represents the set of electrodes using a directed graph in which nodes correspond to recording electrodes and the edges' weights quantify the pair-wise causal influence between the recorded signals. Then, the algorithm infers the SOZ from the estimated graph using a variant of the PageRank algorithm followed by a novel post-processing phase. Inference results for 19 patients show a close match between the SOZ inferred by the proposed approach and the SOZ estimated by expert neurologists (success rate of 17 out of 19.

  19. Local interaction simulation approach to modelling nonclassical, nonlinear elastic behavior in solids.

    Science.gov (United States)

    Scalerandi, Marco; Agostini, Valentina; Delsanto, Pier Paolo; Van Den Abeele, Koen; Johnson, Paul A

    2003-06-01

    Recent studies show that a broad category of materials share "nonclassical" nonlinear elastic behavior much different from "classical" (Landau-type) nonlinearity. Manifestations of "nonclassical" nonlinearity include stress-strain hysteresis and discrete memory in quasistatic experiments, and specific dependencies of the harmonic amplitudes with respect to the drive amplitude in dynamic wave experiments, which are remarkably different from those predicted by the classical theory. These materials have in common soft "bond" elements, where the elastic nonlinearity originates, contained in hard matter (e.g., a rock sample). The bond system normally comprises a small fraction of the total material volume, and can be localized (e.g., a crack in a solid) or distributed, as in a rock. In this paper a model is presented in which the soft elements are treated as hysteretic or reversible elastic units connected in a one-dimensional lattice to elastic elements (grains), which make up the hard matrix. Calculations are performed in the framework of the local interaction simulation approach (LISA). Experimental observations are well predicted by the model, which is now ready both for basic investigations about the physical origins of nonlinear elasticity and for applications to material damage diagnostics.

  20. Mitigating Local Natural Disaster through Social Aware Preparedness Using Complexity Approach

    Science.gov (United States)

    Supadli, Irwan; Saputri, Andini; Mawengkang, Herman

    2018-01-01

    During and after natural disaster, such as, eruption of vulcano, many people have to abandon their living place to a temporary shelter. Usually, there could be several time for the occurrence of the eruption. This situation, for example, happened at Sinabung vulcano, located in Karo district of North Sumatera Province, Indonesia. The people in the disaster area have become indifferent. In terms of the society, the local natural disaster problem belong to a complex societal problem. This research is to find a way what should be done to these society to raise their social awareness that they had experienced serious natural disaster and they will be able to live normally and sustainable as before. Societal complexity approach is used to solve the problems. Social studies referred to in this activity are to analyze the social impacts arising from the implementation of the relocation itself. Scope of social impact assessments include are The social impact of the development program of relocation, including the impact of construction activities and long-term impact of construction activity, particularly related to the source and use of clean water, sewerage system, drainage and waste management (solid waste), Social impacts arising associated with occupant relocation sites and the availability of infrastructure (public facilities, include: worship facilities, health and education) in the local environment (pre-existing). Social analysis carried out on the findings of the field, the study related documents and observations of the condition of the existing social environment Siosar settlements.

  1. Noise Localization Method for Model Tests in a Large Cavitation Tunnel Using a Hydrophone Array

    Directory of Open Access Journals (Sweden)

    Cheolsoo Park

    2016-02-01

    Full Text Available Model tests are performed in order to predict the noise level of a full ship and to control its noise signature. Localizing noise sources in the model test is therefore an important research subject along with measuring noise levels. In this paper, a noise localization method using a hydrophone array in a large cavitation tunnel is presented. The 45-channel hydrophone array was designed using a global optimization technique for noise measurement. A set of noise experiments was performed in the KRISO (Korea Research Institute of Ships & Ocean Engineering large cavitation tunnel using scaled models, including a ship with a single propeller, a ship with twin propellers and an underwater vehicle. The incoherent broadband processors defined based on the Bartlett and the minimum variance (MV processors were applied to the measured data. The results of data analysis and localization are presented in the paper. Finally, it is shown that the mechanical noise, as well as the propeller noise can be successfully localized using the proposed localization method.

  2. Impact Localization Method for Composite Plate Based on Low Sampling Rate Embedded Fiber Bragg Grating Sensors

    Directory of Open Access Journals (Sweden)

    Zhuo Pang

    2017-01-01

    Full Text Available Fiber Bragg Grating (FBG sensors have been increasingly used in the field of Structural Health Monitoring (SHM in recent years. In this paper, we proposed an impact localization algorithm based on the Empirical Mode Decomposition (EMD and Particle Swarm Optimization-Support Vector Machine (PSO-SVM to achieve better localization accuracy for the FBG-embedded plate. In our method, EMD is used to extract the features of FBG signals, and PSO-SVM is then applied to automatically train a classification model for the impact localization. Meanwhile, an impact monitoring system for the FBG-embedded composites has been established to actually validate our algorithm. Moreover, the relationship between the localization accuracy and the distance from impact to the nearest sensor has also been studied. Results suggest that the localization accuracy keeps increasing and is satisfactory, ranging from 93.89% to 97.14%, on our experimental conditions with the decrease of the distance. This article reports an effective and easy-implementing method for FBG signal processing on SHM systems of the composites.

  3. Hierarchical leak detection and localization method in natural gas pipeline monitoring sensor networks.

    Science.gov (United States)

    Wan, Jiangwen; Yu, Yang; Wu, Yinfeng; Feng, Renjian; Yu, Ning

    2012-01-01

    In light of the problems of low recognition efficiency, high false rates and poor localization accuracy in traditional pipeline security detection technology, this paper proposes a type of hierarchical leak detection and localization method for use in natural gas pipeline monitoring sensor networks. In the signal preprocessing phase, original monitoring signals are dealt with by wavelet transform technology to extract the single mode signals as well as characteristic parameters. In the initial recognition phase, a multi-classifier model based on SVM is constructed and characteristic parameters are sent as input vectors to the multi-classifier for initial recognition. In the final decision phase, an improved evidence combination rule is designed to integrate initial recognition results for final decisions. Furthermore, a weighted average localization algorithm based on time difference of arrival is introduced for determining the leak point's position. Experimental results illustrate that this hierarchical pipeline leak detection and localization method could effectively improve the accuracy of the leak point localization and reduce the undetected rate as well as false alarm rate.

  4. Hierarchical Leak Detection and Localization Method in Natural Gas Pipeline Monitoring Sensor Networks

    Directory of Open Access Journals (Sweden)

    Ning Yu

    2011-12-01

    Full Text Available In light of the problems of low recognition efficiency, high false rates and poor localization accuracy in traditional pipeline security detection technology, this paper proposes a type of hierarchical leak detection and localization method for use in natural gas pipeline monitoring sensor networks. In the signal preprocessing phase, original monitoring signals are dealt with by wavelet transform technology to extract the single mode signals as well as characteristic parameters. In the initial recognition phase, a multi-classifier model based on SVM is constructed and characteristic parameters are sent as input vectors to the multi-classifier for initial recognition. In the final decision phase, an improved evidence combination rule is designed to integrate initial recognition results for final decisions. Furthermore, a weighted average localization algorithm based on time difference of arrival is introduced for determining the leak point’s position. Experimental results illustrate that this hierarchical pipeline leak detection and localization method could effectively improve the accuracy of the leak point localization and reduce the undetected rate as well as false alarm rate.

  5. Hierarchical Leak Detection and Localization Method in Natural Gas Pipeline Monitoring Sensor Networks

    Science.gov (United States)

    Wan, Jiangwen; Yu, Yang; Wu, Yinfeng; Feng, Renjian; Yu, Ning

    2012-01-01

    In light of the problems of low recognition efficiency, high false rates and poor localization accuracy in traditional pipeline security detection technology, this paper proposes a type of hierarchical leak detection and localization method for use in natural gas pipeline monitoring sensor networks. In the signal preprocessing phase, original monitoring signals are dealt with by wavelet transform technology to extract the single mode signals as well as characteristic parameters. In the initial recognition phase, a multi-classifier model based on SVM is constructed and characteristic parameters are sent as input vectors to the multi-classifier for initial recognition. In the final decision phase, an improved evidence combination rule is designed to integrate initial recognition results for final decisions. Furthermore, a weighted average localization algorithm based on time difference of arrival is introduced for determining the leak point’s position. Experimental results illustrate that this hierarchical pipeline leak detection and localization method could effectively improve the accuracy of the leak point localization and reduce the undetected rate as well as false alarm rate. PMID:22368464

  6. A geologic approach to field methods in fluvial geomorphology

    Science.gov (United States)

    Fitzpatrick, Faith A.; Thornbush, Mary J; Allen, Casey D; Fitzpatrick, Faith A.

    2014-01-01

    A geologic approach to field methods in fluvial geomorphology is useful for understanding causes and consequences of past, present, and possible future perturbations in river behavior and floodplain dynamics. Field methods include characterizing river planform and morphology changes and floodplain sedimentary sequences over long periods of time along a longitudinal river continuum. Techniques include topographic and bathymetric surveying of fluvial landforms in valley bottoms and describing floodplain sedimentary sequences through coring, trenching, and examining pits and exposures. Historical sediment budgets that include floodplain sedimentary records can characterize past and present sources and sinks of sediment along a longitudinal river continuum. Describing paleochannels and floodplain vertical accretion deposits, estimating long-term sedimentation rates, and constructing historical sediment budgets can assist in management of aquatic resources, habitat, sedimentation, and flooding issues.

  7. Compression-RSA: New approach of encryption and decryption method

    Science.gov (United States)

    Hung, Chang Ee; Mandangan, Arif

    2013-04-01

    Rivest-Shamir-Adleman (RSA) cryptosystem is a well known asymmetric cryptosystem and it has been applied in a very wide area. Many researches with different approaches have been carried out in order to improve the security and performance of RSA cryptosystem. The enhancement of the performance of RSA cryptosystem is our main interest. In this paper, we propose a new method to increase the efficiency of RSA by shortening the number of plaintext before it goes under encryption process without affecting the original content of the plaintext. Concept of simple Continued Fraction and the new special relationship between it and Euclidean Algorithm have been applied on this newly proposed method. By reducing the number of plaintext-ciphertext, the encryption-decryption processes of a secret message can be accelerated.

  8. Securing Metering Infrastructure of Smart Grid: A Machine Learning and Localization Based Key Management Approach

    Directory of Open Access Journals (Sweden)

    Imtiaz Parvez

    2016-08-01

    Full Text Available In smart cities, advanced metering infrastructure (AMI of the smart grid facilitates automated metering, control and monitoring of power distribution by employing a wireless network. Due to this wireless nature of communication, there exist potential threats to the data privacy in AMI. Decoding the energy consumption reading, injecting false data/command signals and jamming the networks are some hazardous measures against this technology. Since a smart meter possesses limited memory and computational capability, AMI demands a light, but robust security scheme. In this paper, we propose a localization-based key management system for meter data encryption. Data are encrypted by the key associated with the coordinate of the meter and a random key index. The encryption keys are managed and distributed by a trusted third party (TTP. Localization of the meter is proposed by a method based on received signal strength (RSS using the maximum likelihood estimator (MLE. The received packets are decrypted at the control center with the key mapped with the key index and the meter’s coordinates. Additionally, we propose the k-nearest neighbors (kNN algorithm for node/meter authentication, capitalizing further on data transmission security. Finally, we evaluate the security strength of a data packet numerically for our method.

  9. Improving Signal-to-Noise Ratio in Susceptibility Weighted Imaging: A Novel Multicomponent Non-Local Approach.

    Directory of Open Access Journals (Sweden)

    Pasquale Borrelli

    Full Text Available In susceptibility-weighted imaging (SWI, the high resolution required to obtain a proper contrast generation leads to a reduced signal-to-noise ratio (SNR. The application of a denoising filter to produce images with higher SNR and still preserve small structures from excessive blurring is therefore extremely desirable. However, as the distributions of magnitude and phase noise may introduce biases during image restoration, the application of a denoising filter is non-trivial. Taking advantage of the potential multispectral nature of MR images, a multicomponent approach using a Non-Local Means (MNLM denoising filter may perform better than a component-by-component image restoration method. Here we present a new MNLM-based method (Multicomponent-Imaginary-Real-SWI, hereafter MIR-SWI to produce SWI images with high SNR and improved conspicuity. Both qualitative and quantitative comparisons of MIR-SWI with the original SWI scheme and previously proposed SWI restoring pipelines showed that MIR-SWI fared consistently better than the other approaches. Noise removal with MIR-SWI also provided improvement in contrast-to-noise ratio (CNR and vessel conspicuity at higher factors of phase mask multiplications than the one suggested in the literature for SWI vessel imaging. We conclude that a proper handling of noise in the complex MR dataset may lead to improved image quality for SWI data.

  10. METHODICAL APPROACH TO AN ESTIMATION OF PROFESSIONALISM OF AN EMPLOYEE

    Directory of Open Access Journals (Sweden)

    Татьяна Александровна Коркина

    2013-08-01

    Full Text Available Analysis of definitions of «professionalism», reflecting the different viewpoints of scientists and practitioners, has shown that it is interpreted as a specific property of the people effectively and reliably carry out labour activity in a variety of conditions. The article presents the methodical approach to an estimation of professionalism of the employee from the position as the external manifestations of the reliability and effectiveness of the work and the position of the personal characteristics of the employee, determining the results of his work. This approach includes the assessment of the level of qualification and motivation of the employee for each key job functions as well as the final results of its implementation on the criteria of efficiency and reliability. The proposed methodological approach to the estimation of professionalism of the employee allows to identify «bottlenecks» in the structure of its labour functions and to define directions of development of the professional qualities of the worker to ensure the required level of reliability and efficiency of the obtained results.DOI: http://dx.doi.org/10.12731/2218-7405-2013-6-11

  11. A Bayesian approach to real-time 3D tumor localization via monoscopic x-ray imaging during treatment delivery

    International Nuclear Information System (INIS)

    Li, Ruijiang; Fahimian, Benjamin P.; Xing, Lei

    2011-01-01

    Purpose: Monoscopic x-ray imaging with on-board kV devices is an attractive approach for real-time image guidance in modern radiation therapy such as VMAT or IMRT, but it falls short in providing reliable information along the direction of imaging x-ray. By effectively taking consideration of projection data at prior times and/or angles through a Bayesian formalism, the authors develop an algorithm for real-time and full 3D tumor localization with a single x-ray imager during treatment delivery. Methods: First, a prior probability density function is constructed using the 2D tumor locations on the projection images acquired during patient setup. Whenever an x-ray image is acquired during the treatment delivery, the corresponding 2D tumor location on the imager is used to update the likelihood function. The unresolved third dimension is obtained by maximizing the posterior probability distribution. The algorithm can also be used in a retrospective fashion when all the projection images during the treatment delivery are used for 3D localization purposes. The algorithm does not involve complex optimization of any model parameter and therefore can be used in a ''plug-and-play'' fashion. The authors validated the algorithm using (1) simulated 3D linear and elliptic motion and (2) 3D tumor motion trajectories of a lung and a pancreas patient reproduced by a physical phantom. Continuous kV images were acquired over a full gantry rotation with the Varian TrueBeam on-board imaging system. Three scenarios were considered: fluoroscopic setup, cone beam CT setup, and retrospective analysis. Results: For the simulation study, the RMS 3D localization error is 1.2 and 2.4 mm for the linear and elliptic motions, respectively. For the phantom experiments, the 3D localization error is < 1 mm on average and < 1.5 mm at 95th percentile in the lung and pancreas cases for all three scenarios. The difference in 3D localization error for different scenarios is small and is not

  12. The local quantum-mechanical stress tensor in Thomas-Fermi approximation and gradient expansion method

    International Nuclear Information System (INIS)

    Kaschner, R.; Graefenstein, J.; Ziesche, P.

    1988-12-01

    From the local momentum balance using density functional theory an expression for the local quantum-mechanical stress tensor (or stress field) σ(r) of non-relativistic Coulomb systems is found out within the Thomas-Fermi approximation and its generalizations including gradient expansion method. As an illustration the stress field σ(r) is calculated for the jellium model of the interface K-Cs, containing especially the adhesive force between the two half-space jellia. (author). 23 refs, 1 fig

  13. Nonparametric method for failures detection and localization in the actuating subsystem of aircraft control system

    Science.gov (United States)

    Karpenko, S. S.; Zybin, E. Yu; Kosyanchuk, V. V.

    2018-02-01

    In this paper we design a nonparametric method for failures detection and localization in the aircraft control system that uses the measurements of the control signals and the aircraft states only. It doesn’t require a priori information of the aircraft model parameters, training or statistical calculations, and is based on algebraic solvability conditions for the aircraft model identification problem. This makes it possible to significantly increase the efficiency of detection and localization problem solution by completely eliminating errors, associated with aircraft model uncertainties.

  14. Application of radiotracer method for tightness control and leakage localization in industrial objects

    International Nuclear Information System (INIS)

    Kras, J; Walis, L.; Myczkowski, S.

    2001-01-01

    Application of 82 Br in the form of gaseous CH 3 Br for tightness control and leakage localization in large industrial apparatus as chemical reactors, columns, vessels, pipelines etc. has been presented. The tracer has been prepared at the place of measurements in a specially designed mobile chemical reactor. The paper presents different variants of the method convenient for: tightness control of underground pipelines, leakage control of technological objects working in chemical and petrochemical industry, tightness control of large metal vessels localized underground and on surface. The radiometric devices used in mentioned variants have ben performed as well

  15. Local-scaling density-functional method: Intraorbit and interorbit density optimizations

    International Nuclear Information System (INIS)

    Koga, T.; Yamamoto, Y.; Ludena, E.V.

    1991-01-01

    The recently proposed local-scaling density-functional theory provides us with a practical method for the direct variational determination of the electron density function ρ(r). The structure of ''orbits,'' which ensures the one-to-one correspondence between the electron density ρ(r) and the N-electron wave function Ψ({r k }), is studied in detail. For the realization of the local-scaling density-functional calculations, procedures for intraorbit and interorbit optimizations of the electron density function are proposed. These procedures are numerically illustrated for the helium atom in its ground state at the beyond-Hartree-Fock level

  16. Adaptation Method for Overall and Local Performances of Gas Turbine Engine Model

    Science.gov (United States)

    Kim, Sangjo; Kim, Kuisoon; Son, Changmin

    2018-04-01

    An adaptation method was proposed to improve the modeling accuracy of overall and local performances of gas turbine engine. The adaptation method was divided into two steps. First, the overall performance parameters such as engine thrust, thermal efficiency, and pressure ratio were adapted by calibrating compressor maps, and second, the local performance parameters such as temperature of component intersection and shaft speed were adjusted by additional adaptation factors. An optimization technique was used to find the correlation equation of adaptation factors for compressor performance maps. The multi-island genetic algorithm (MIGA) was employed in the present optimization. The correlations of local adaptation factors were generated based on the difference between the first adapted engine model and performance test data. The proposed adaptation method applied to a low-bypass ratio turbofan engine of 12,000 lb thrust. The gas turbine engine model was generated and validated based on the performance test data in the sea-level static condition. In flight condition at 20,000 ft and 0.9 Mach number, the result of adapted engine model showed improved prediction in engine thrust (overall performance parameter) by reducing the difference from 14.5 to 3.3%. Moreover, there was further improvement in the comparison of low-pressure turbine exit temperature (local performance parameter) as the difference is reduced from 3.2 to 0.4%.

  17. Novel approach in quantitative analysis of shearography method

    International Nuclear Information System (INIS)

    Wan Saffiey Wan Abdullah

    2002-01-01

    The application of laser interferometry in industrial non-destructive testing and material characterization is becoming more prevalent since this method provides non-contact full-field inspection of the test object. However their application only limited to the qualitative analysis, current trend has changed to the development of this method by the introduction of quantitative analysis, which attempts to detail the defect examined. This being the design feature for a ranges of object size to be examined. The growing commercial demand for quantitative analysis for NDT and material characterization is determining the quality of optical and analysis instrument. However very little attention is currently being paid to understanding, quantifying and compensating for the numerous error sources which are a function of interferometers. This paper presents a comparison of measurement analysis using the established theoretical approach and the new approach, taken into account the factor of divergence illumination and other geometrical factors. The difference in the measurement system could be associated in the error factor. (Author)

  18. Fatigue Life Prediction of High Modulus Asphalt Concrete Based on the Local Stress-Strain Method

    Directory of Open Access Journals (Sweden)

    Mulian Zheng

    2017-03-01

    Full Text Available Previously published studies have proposed fatigue life prediction models for dense graded asphalt pavement based on flexural fatigue test. This study focused on the fatigue life prediction of High Modulus Asphalt Concrete (HMAC pavement using the local strain-stress method and direct tension fatigue test. First, the direct tension fatigue test at various strain levels was conducted on HMAC prism samples cut from plate specimens. Afterwards, their true stress-strain loop curves were obtained and modified to develop the strain-fatigue life equation. Then the nominal strain of HMAC course determined using finite element method was converted into local strain using the Neuber method. Finally, based on the established fatigue equation and converted local strain, a method to predict the pavement fatigue crack initiation life was proposed and the fatigue life of a typical HMAC overlay pavement which runs a risk of bottom-up cracking was predicted and validated. Results show that the proposed method was able to produce satisfactory crack initiation life.

  19. Three approaches in the research field of ethnomodeling: emic (local, etic (global, and dialogical (glocal

    Directory of Open Access Journals (Sweden)

    Daniel C. Orey

    2015-07-01

    Full Text Available The acquisition of both emic (local and etic (global knowledge is an alternative goal for the implementation of ethnomodeling research. Emic knowledge is essential for an intuitive and empathic understanding of mathematical ideas, procedures, and practices developed by the members of distinct cultural groups. It is essential for conducting effective ethnographic fieldwork. Furthermore, emic knowledge is a valuable source of inspiration for etic hypotheses. Etic knowledge is essential for cross-cultural comparisons, which are based on the components of ethnology. In this regard, such comparisons demand standard units and categories to facilitate communication. Dialogical (glocal is a third approach for ethnomodeling research that makes use of both emic and etic knowledge traditions through processes of dialogue and interaction. Ethnomodeling is defined as the study of mathematical phenomena within a culture because it is a social construct and is culturally bound. Finally, the objective of this article is to show how we have come to use a combination of emic, etic and dialogical (glocal approaches in our work in the area of ethnomodeling, which contributes to the acquisition of a more complete understanding of mathematical practices developed by the members of distinct cultural groups.

  20. Process planning optimization on turning machine tool using a hybrid genetic algorithm with local search approach

    Directory of Open Access Journals (Sweden)

    Yuliang Su

    2015-04-01

    Full Text Available A turning machine tool is a kind of new type of machine tool that is equipped with more than one spindle and turret. The distinctive simultaneous and parallel processing abilities of turning machine tool increase the complexity of process planning. The operations would not only be sequenced and satisfy precedence constraints, but also should be scheduled with multiple objectives such as minimizing machining cost, maximizing utilization of turning machine tool, and so on. To solve this problem, a hybrid genetic algorithm was proposed to generate optimal process plans based on a mixed 0-1 integer programming model. An operation precedence graph is used to represent precedence constraints and help generate a feasible initial population of hybrid genetic algorithm. Encoding strategy based on data structure was developed to represent process plans digitally in order to form the solution space. In addition, a local search approach for optimizing the assignments of available turrets would be added to incorporate scheduling with process planning. A real-world case is used to prove that the proposed approach could avoid infeasible solutions and effectively generate a global optimal process plan.

  1. MAIN LAND USE PLANNING APPROACHES TO STRUCTURAL ELEMENTS LOCAL ECOLOGICAL NETWORK

    Directory of Open Access Journals (Sweden)

    TretiakV.M.

    2016-08-01

    Full Text Available In modern conditions of social development, changes in land eco-system of economic relations in Ukraine, the problem of providing conditions for the creation of sustainable land use and creation of protected areas get the status of special urgency. Ideology establishment of ecological networks became logical continuation of environmental thought in general. Considering the methodological approach to the establishment of ecological networks we can constitute, that it is an environmental frame of spatial infrastructure, land conservation and environmental areas, major part of land is the basis of the structural elements of ecological network. Designing an ecological network is made through developing regional schemes of Econet formation, regional and local schemes for establishing an ecological network areas, settlements and other areas. Land Management uses design of structural elements of the ecological network in the village council, as a rule, begins with ecological and landscape mikrozonationof the village council, held during the preparatory work for the land drafting and finishing the formation of environmentally homogeneous regions, which represents the tied system components of ecological network, environmental measures in the form of local environmental restrictions (encumbrances to use land and other natural resources. Additionally, there are some project organization and territorial measures that increase the sustainability area, such as: key, binders, buffer areas and renewable ecological network. Land management projects on the formation of structural elements of ecological network as territorial restrictions (encumbrances in land are used within the territories Councils determined the location and size of land: - Protection zones around especially valuable natural objects of cultural heritage, meteorological stations, etc. in order to protect them from adverse human impacts; - Protection zones along telecommunication lines, power

  2. Estimating the Impacts of Local Policy Innovation: The Synthetic Control Method Applied to Tropical Deforestation.

    Science.gov (United States)

    Sills, Erin O; Herrera, Diego; Kirkpatrick, A Justin; Brandão, Amintas; Dickson, Rebecca; Hall, Simon; Pattanayak, Subhrendu; Shoch, David; Vedoveto, Mariana; Young, Luisa; Pfaff, Alexander

    2015-01-01

    Quasi-experimental methods increasingly are used to evaluate the impacts of conservation interventions by generating credible estimates of counterfactual baselines. These methods generally require large samples for statistical comparisons, presenting a challenge for evaluating innovative policies implemented within a few pioneering jurisdictions. Single jurisdictions often are studied using comparative methods, which rely on analysts' selection of best case comparisons. The synthetic control method (SCM) offers one systematic and transparent way to select cases for comparison, from a sizeable pool, by focusing upon similarity in outcomes before the intervention. We explain SCM, then apply it to one local initiative to limit deforestation in the Brazilian Amazon. The municipality of Paragominas launched a multi-pronged local initiative in 2008 to maintain low deforestation while restoring economic production. This was a response to having been placed, due to high deforestation, on a federal "blacklist" that increased enforcement of forest regulations and restricted access to credit and output markets. The local initiative included mapping and monitoring of rural land plus promotion of economic alternatives compatible with low deforestation. The key motivation for the program may have been to reduce the costs of blacklisting. However its stated purpose was to limit deforestation, and thus we apply SCM to estimate what deforestation would have been in a (counterfactual) scenario of no local initiative. We obtain a plausible estimate, in that deforestation patterns before the intervention were similar in Paragominas and the synthetic control, which suggests that after several years, the initiative did lower deforestation (significantly below the synthetic control in 2012). This demonstrates that SCM can yield helpful land-use counterfactuals for single units, with opportunities to integrate local and expert knowledge and to test innovations and permutations on policies

  3. Estimating the Impacts of Local Policy Innovation: The Synthetic Control Method Applied to Tropical Deforestation

    Science.gov (United States)

    Sills, Erin O.; Herrera, Diego; Kirkpatrick, A. Justin; Brandão, Amintas; Dickson, Rebecca; Hall, Simon; Pattanayak, Subhrendu; Shoch, David; Vedoveto, Mariana; Young, Luisa; Pfaff, Alexander

    2015-01-01

    Quasi-experimental methods increasingly are used to evaluate the impacts of conservation interventions by generating credible estimates of counterfactual baselines. These methods generally require large samples for statistical comparisons, presenting a challenge for evaluating innovative policies implemented within a few pioneering jurisdictions. Single jurisdictions often are studied using comparative methods, which rely on analysts’ selection of best case comparisons. The synthetic control method (SCM) offers one systematic and transparent way to select cases for comparison, from a sizeable pool, by focusing upon similarity in outcomes before the intervention. We explain SCM, then apply it to one local initiative to limit deforestation in the Brazilian Amazon. The municipality of Paragominas launched a multi-pronged local initiative in 2008 to maintain low deforestation while restoring economic production. This was a response to having been placed, due to high deforestation, on a federal “blacklist” that increased enforcement of forest regulations and restricted access to credit and output markets. The local initiative included mapping and monitoring of rural land plus promotion of economic alternatives compatible with low deforestation. The key motivation for the program may have been to reduce the costs of blacklisting. However its stated purpose was to limit deforestation, and thus we apply SCM to estimate what deforestation would have been in a (counterfactual) scenario of no local initiative. We obtain a plausible estimate, in that deforestation patterns before the intervention were similar in Paragominas and the synthetic control, which suggests that after several years, the initiative did lower deforestation (significantly below the synthetic control in 2012). This demonstrates that SCM can yield helpful land-use counterfactuals for single units, with opportunities to integrate local and expert knowledge and to test innovations and permutations on

  4. Estimating the Impacts of Local Policy Innovation: The Synthetic Control Method Applied to Tropical Deforestation.

    Directory of Open Access Journals (Sweden)

    Erin O Sills

    Full Text Available Quasi-experimental methods increasingly are used to evaluate the impacts of conservation interventions by generating credible estimates of counterfactual baselines. These methods generally require large samples for statistical comparisons, presenting a challenge for evaluating innovative policies implemented within a few pioneering jurisdictions. Single jurisdictions often are studied using comparative methods, which rely on analysts' selection of best case comparisons. The synthetic control method (SCM offers one systematic and transparent way to select cases for comparison, from a sizeable pool, by focusing upon similarity in outcomes before the intervention. We explain SCM, then apply it to one local initiative to limit deforestation in the Brazilian Amazon. The municipality of Paragominas launched a multi-pronged local initiative in 2008 to maintain low deforestation while restoring economic production. This was a response to having been placed, due to high deforestation, on a federal "blacklist" that increased enforcement of forest regulations and restricted access to credit and output markets. The local initiative included mapping and monitoring of rural land plus promotion of economic alternatives compatible with low deforestation. The key motivation for the program may have been to reduce the costs of blacklisting. However its stated purpose was to limit deforestation, and thus we apply SCM to estimate what deforestation would have been in a (counterfactual scenario of no local initiative. We obtain a plausible estimate, in that deforestation patterns before the intervention were similar in Paragominas and the synthetic control, which suggests that after several years, the initiative did lower deforestation (significantly below the synthetic control in 2012. This demonstrates that SCM can yield helpful land-use counterfactuals for single units, with opportunities to integrate local and expert knowledge and to test innovations and

  5. Laplace transform series expansion method for solving the local fractional heat-transfer equation defined on Cantor sets

    Directory of Open Access Journals (Sweden)

    Sun Huan

    2016-01-01

    Full Text Available In this paper, we use the Laplace transform series expansion method to find the analytical solution for the local fractional heat-transfer equation defined on Cantor sets via local fractional calculus.

  6. The Methodical Approaches to the Research of Informatization of the Global Economic Development

    Directory of Open Access Journals (Sweden)

    Kazakova Nadezhda A.

    2018-03-01

    Full Text Available The article is aimed at researching the identification of global economic development informatization. The complex of issues connected with research of development of informatization of the world countries in the conditions of globalization is considered. The development of informatization in the global economic space, which facilitates opening of new markets for international trade enterprises, international transnational corporations and other organizations, which not only provide exports, but also create production capacities for local producers. The methodical approach which includes three stages together with formation of the input information on the status of informatization of the global economic development of the world countries has been proposed.

  7. Nuclear Enhanced X-ray Maximum Entropy Method Used to Analyze Local Distortions in Simple Structures

    DEFF Research Database (Denmark)

    Christensen, Sebastian; Bindzus, Niels; Christensen, Mogens

    We introduce a novel method for reconstructing pseudo nuclear density distributions (NDDs): Nuclear Enhanced X-ray Maximum Entropy Method (NEXMEM). NEXMEM offers an alternative route to experimental NDDs, exploiting the superior quality of synchrotron X-ray data compared to neutron data. The method...... proposed to result from anharmonic phonon scattering or from local fluctuating dipoles on the Pb site.[1,2] No macroscopic symmetry change are associated with these effects, rendering them invisible to conventional crystallographic techniques. For this reason PbX was until recently believed to adopt...

  8. Determination of the Local Thermal Conductivity of Functionally Graded Materials by a Laser Flash Method

    DEFF Research Database (Denmark)

    Zajas, Jan Jakub; Heiselberg, Per

    2013-01-01

    Determination of thermal conductivity of construction materials is essential to estimate their insulation capabilities. In most cases, homogenous materials are used and well developed methods exist for measurements of their thermal conductivity. The task becomes more challenging when dealing...... by scanning them point by point and determining the thermal conductivity as a function of the spatial dimensions. The method proves to be repeatable and of reasonable accuracy and can be used to determine the local thermal properties on a scale of millimeters. In this study, the method was successfully...... applied to create a map of thermal conductivity of a functionally graded material sample....

  9. A New Spectral Local Linearization Method for Nonlinear Boundary Layer Flow Problems

    Directory of Open Access Journals (Sweden)

    S. S. Motsa

    2013-01-01

    Full Text Available We propose a simple and efficient method for solving highly nonlinear systems of boundary layer flow problems with exponentially decaying profiles. The algorithm of the proposed method is based on an innovative idea of linearizing and decoupling the governing systems of equations and reducing them into a sequence of subsystems of differential equations which are solved using spectral collocation methods. The applicability of the proposed method, hereinafter referred to as the spectral local linearization method (SLLM, is tested on some well-known boundary layer flow equations. The numerical results presented in this investigation indicate that the proposed method, despite being easy to develop and numerically implement, is very robust in that it converges rapidly to yield accurate results and is more efficient in solving very large systems of nonlinear boundary value problems of the similarity variable boundary layer type. The accuracy and numerical stability of the SLLM can further be improved by using successive overrelaxation techniques.

  10. Standardless quantification approach of TXRF analysis using fundamental parameter method

    International Nuclear Information System (INIS)

    Szaloki, I.; Taniguchi, K.

    2000-01-01

    New standardless evaluation procedure based on the fundamental parameter method (FPM) has been developed for TXRF analysis. The theoretical calculation describes the relationship between characteristic intensities and the geometrical parameters of the excitation, detection system and the specimen parameters: size, thickness, angle of the excitation beam to the surface and the optical properties of the specimen holder. Most of the TXRF methods apply empirical calibration, which requires the application of special preparation technique. However, the characteristic lines of the specimen holder (Si Kα,β) present information from the local excitation and geometrical conditions on the substrate surface. On the basis of the theoretically calculation of the substrate characteristic intensity the excitation beam flux can be approximated. Taking into consideration the elements are in the specimen material a system of non-linear equation can be given involving the unknown concentration values and the geometrical and detection parameters. In order to solve this mathematical problem PASCAL software was written, which calculates the sample composition and the average sample thickness by gradient algorithm. Therefore, this quantitative estimation of the specimen composition requires neither external nor internal standard sample. For verification of the theoretical calculation and the numerical procedure, several experiments were carried out using mixed standard solution containing elements of K, Sc, V, Mn, Co and Cu in 0.1 - 10 ppm concentration range. (author)

  11. An infrared small target detection method based on multiscale local homogeneity measure

    Science.gov (United States)

    Nie, Jinyan; Qu, Shaocheng; Wei, Yantao; Zhang, Liming; Deng, Lizhen

    2018-05-01

    Infrared (IR) small target detection plays an important role in the field of image detection area owing to its intrinsic characteristics. This paper presents a multiscale local homogeneity measure (MLHM) for infrared small target detection, which can enhance the performance of IR small target detection system. Firstly, intra-patch homogeneity of the target itself and the inter-patch heterogeneity between target and the local background regions are integrated to enhance the significant of small target. Secondly, a multiscale measure based on local regions is proposed to obtain the most appropriate response. Finally, an adaptive threshold method is applied to small target segmentation. Experimental results on three different scenarios indicate that the MLHM has good performance under the interference of strong noise.

  12. Seismic data two-step recovery approach combining sparsity-promoting and hyperbolic Radon transform methods

    International Nuclear Information System (INIS)

    Wang, Hanchuang; Chen, Shengchang; Ren, Haoran; Liang, Donghui; Zhou, Huamin; She, Deping

    2015-01-01

    In current research of seismic data recovery problems, the sparsity-promoting method usually produces an insufficient recovery result at the locations of null traces. The HRT (hyperbolic Radon transform) method can be applied to problems of seismic data recovery with approximately hyperbolic events. Influenced by deviations of hyperbolic characteristics between real and ideal travel-time curves, some spurious events are usually introduced and the recovery effect of intermediate and far-offset traces is worse than that of near-offset traces. Sparsity-promoting recovery is primarily dependent on the sparsity of seismic data in the sparse transform domain (i.e. on the local waveform characteristics), whereas HRT recovery is severely affected by the global characteristics of the seismic events. Inspired by the above conclusion, a two-step recovery approach combining sparsity-promoting and time-invariant HRT methods is proposed, which is based on both local and global characteristics of the seismic data. Two implementation strategies are presented in detail, and the selection criteria of the relevant strategies is also discussed. Numerical examples of synthetic and real data verify that the new approach can achieve a better recovery effect by simultaneously overcoming the shortcomings of sparsity-promoting recovery and HRT recovery. (paper)

  13. A practical and applied approach to assessing the cross cutting nature of child injury prevention as a basis for policy making at the local level

    Directory of Open Access Journals (Sweden)

    Beatrice Scholtes

    2015-12-01

    Full Text Available Aim: Risk factors for child injury are multi-faceted. Social, environmental and economic factors place responsibility for prevention upon many stakeholders across traditional sectors such as health, justice, environment and education. Multi-sectoral collaboration for injury prevention is thus essential. In addition, co-benefits due to injury prevention initiatives exist. However, multi-sectoral collaboration is often difficult to establish and maintain. We present an applied approach for practitioners and policy makers at the local level to use to explore and address the multi-sectoral nature of child injury. Methods: We combined elements of the Haddon Matrix and the Lens and Telescope model, to develop a new approach for practitioners and policy makers at the local level. Results: The approach offers the opportunity for diverse sectors at the local level to work together to identify their role in child injury prevention. Based on ecological injury prevention and life-course epidemiology it encourages multi-disciplinary team building from the outset. The process has three phases: first, visualising the multi-sectoral responsibilities for child injury prevention in the local area; second,  demonstrating the need for multi-sectoral collaboration and helping plan prevention activities together; and third, visualising potential co-benefits to other sectors and age groups that may arise from child injury prevention initiatives. Conclusion: The approach and process encourages inter-sectoral collaboration for child injury prevention at the local level. It is a useful addition for child injury  prevention at the local level, however testing the practicality of the approach in a real-world setting, and refinement of the process would improve it further.

  14. A novel full-field experimental method to measure the local compressibility of gas diffusion media

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Yeh-Hung; Li, Yongqiang [Electrochemical Energy Research Lab, GM R and D, Honeoye Falls, NY 14472 (United States); Rock, Jeffrey A. [GM Powertrain, Honeoye Falls, NY 14472 (United States)

    2010-05-15

    The gas diffusion medium (GDM) in a proton exchange membrane (PEM) fuel cell needs to simultaneously satisfy the requirements of transporting reactant gases, removing product water, conducting electrons and heat, and providing mechanical support to the membrane electrode assembly (MEA). Concerning the localized over-compression which may force carbon fibers and other conductive debris into the membrane to cause fuel cell failure by electronically shorting through the membrane, we have developed a novel full-field experimental method to measure the local thickness and compressibility of GDM. Applying a uniform air pressure upon a thin polyimide film bonded on the top surface of the GDM with support from the bottom by a flat metal substrate and measuring the thickness change using the 3-D digital image correlation technique with an out-of-plane displacement resolution less than 0.5 {mu}m, we have determined the local thickness and compressive stress/strain behavior in the GDM. Using the local thickness and compressibility data over an area of 11.2 mm x 11.2 mm, we numerically construct the nominal compressive response of a commercial Toray trademark TGP-H-060 based GDM subjected to compression by flat platens. Good agreement in the nominal stress/strain curves from the numerical construction and direct experimental flat-platen measurement confirms the validity of the methodology proposed in this article. The result shows that a nominal pressure of 1.4 MPa compressed between two flat platens can introduce localized compressive stress concentration of more than 3 MPa in up to 1% of the total area at various locations from several hundred micrometers to 1 mm in diameter. We believe that this full-field experimental method can be useful in GDM material and process development to reduce the local hard spots and help to mitigate the membrane shorting failure in PEM fuel cells. (author)

  15. A novel full-field experimental method to measure the local compressibility of gas diffusion media

    Science.gov (United States)

    Lai, Yeh-Hung; Li, Yongqiang; Rock, Jeffrey A.

    The gas diffusion medium (GDM) in a proton exchange membrane (PEM) fuel cell needs to simultaneously satisfy the requirements of transporting reactant gases, removing product water, conducting electrons and heat, and providing mechanical support to the membrane electrode assembly (MEA). Concerning the localized over-compression which may force carbon fibers and other conductive debris into the membrane to cause fuel cell failure by electronically shorting through the membrane, we have developed a novel full-field experimental method to measure the local thickness and compressibility of GDM. Applying a uniform air pressure upon a thin polyimide film bonded on the top surface of the GDM with support from the bottom by a flat metal substrate and measuring the thickness change using the 3-D digital image correlation technique with an out-of-plane displacement resolution less than 0.5 μm, we have determined the local thickness and compressive stress/strain behavior in the GDM. Using the local thickness and compressibility data over an area of 11.2 mm × 11.2 mm, we numerically construct the nominal compressive response of a commercial Toray™ TGP-H-060 based GDM subjected to compression by flat platens. Good agreement in the nominal stress/strain curves from the numerical construction and direct experimental flat-platen measurement confirms the validity of the methodology proposed in this article. The result shows that a nominal pressure of 1.4 MPa compressed between two flat platens can introduce localized compressive stress concentration of more than 3 MPa in up to 1% of the total area at various locations from several hundred micrometers to 1 mm in diameter. We believe that this full-field experimental method can be useful in GDM material and process development to reduce the local hard spots and help to mitigate the membrane shorting failure in PEM fuel cells.

  16. MANAGING THE ACOUSTIC CLIMATE IN LOCAL GOVERNMENT UNITS – A NEW APPROACH

    Directory of Open Access Journals (Sweden)

    Waldemar PASZKOWSKI

    2013-01-01

    Full Text Available The paper presents a new approach to shaping acoustic comfort as a process of managing the acoustic environment in urbanised areas. The research in this area focuses on the psychoacoustic aspect of shaping acoustic comfort in an urban environment. This approach permits, depending on the purpose of land, not only to reduce the noise to the allowable limits but also to evaluate the acoustic quality of sounds originating in different sources. In this context, a review was performed of the research carried out on identifying soundscapes as a way of shaping acoustic comfort in the urban environment. In this paper it is suggested that the entropy method be used for the assessment of auditory sound perception. The research carried out by the author shows that linking the relationship between the quality of perceived sounds with the elements/factors which shape the acoustic environment can be used to valorise soundscapes.

  17. Methods for simultaneously identifying coherent local clusters with smooth global patterns in gene expression profiles

    Directory of Open Access Journals (Sweden)

    Lee Yun-Shien

    2008-03-01

    Full Text Available Abstract Background The hierarchical clustering tree (HCT with a dendrogram 1 and the singular value decomposition (SVD with a dimension-reduced representative map 2 are popular methods for two-way sorting the gene-by-array matrix map employed in gene expression profiling. While HCT dendrograms tend to optimize local coherent clustering patterns, SVD leading eigenvectors usually identify better global grouping and transitional structures. Results This study proposes a flipping mechanism for a conventional agglomerative HCT using a rank-two ellipse (R2E, an improved SVD algorithm for sorting purpose seriation by Chen 3 as an external reference. While HCTs always produce permutations with good local behaviour, the rank-two ellipse seriation gives the best global grouping patterns and smooth transitional trends. The resulting algorithm automatically integrates the desirable properties of each method so that users have access to a clustering and visualization environment for gene expression profiles that preserves coherent local clusters and identifies global grouping trends. Conclusion We demonstrate, through four examples, that the proposed method not only possesses better numerical and statistical properties, it also provides more meaningful biomedical insights than other sorting algorithms. We suggest that sorted proximity matrices for genes and arrays, in addition to the gene-by-array expression matrix, can greatly aid in the search for comprehensive understanding of gene expression structures. Software for the proposed methods can be obtained at http://gap.stat.sinica.edu.tw/Software/GAP.

  18. Electrostatic Discharge Current Linear Approach and Circuit Design Method

    Directory of Open Access Journals (Sweden)

    Pavlos K. Katsivelis

    2010-11-01

    Full Text Available The Electrostatic Discharge phenomenon is a great threat to all electronic devices and ICs. An electric charge passing rapidly from a charged body to another can seriously harm the last one. However, there is a lack in a linear mathematical approach which will make it possible to design a circuit capable of producing such a sophisticated current waveform. The commonly accepted Electrostatic Discharge current waveform is the one set by the IEC 61000-4-2. However, the over-simplified circuit included in the same standard is incapable of producing such a waveform. Treating the Electrostatic Discharge current waveform of the IEC 61000-4-2 as reference, an approximation method, based on Prony’s method, is developed and applied in order to obtain a linear system’s response. Considering a known input, a method to design a circuit, able to generate this ESD current waveform in presented. The circuit synthesis assumes ideal active elements. A simulation is carried out using the PSpice software.

  19. Novel approaches to improve iris recognition system performance based on local quality evaluation and feature fusion.

    Science.gov (United States)

    Chen, Ying; Liu, Yuanning; Zhu, Xiaodong; Chen, Huiling; He, Fei; Pang, Yutong

    2014-01-01

    For building a new iris template, this paper proposes a strategy to fuse different portions of iris based on machine learning method to evaluate local quality of iris. There are three novelties compared to previous work. Firstly, the normalized segmented iris is divided into multitracks and then each track is estimated individually to analyze the recognition accuracy rate (RAR). Secondly, six local quality evaluation parameters are adopted to analyze texture information of each track. Besides, particle swarm optimization (PSO) is employed to get the weights of these evaluation parameters and corresponding weighted coefficients of different tracks. Finally, all tracks' information is fused according to the weights of different tracks. The experimental results based on subsets of three public and one private iris image databases demonstrate three contributions of this paper. (1) Our experimental results prove that partial iris image cannot completely replace the entire iris image for iris recognition system in several ways. (2) The proposed quality evaluation algorithm is a self-adaptive algorithm, and it can automatically optimize the parameters according to iris image samples' own characteristics. (3) Our feature information fusion strategy can effectively improve the performance of iris recognition system.

  20. In silico local structure approach: a case study on outer membrane proteins.

    Science.gov (United States)

    Martin, Juliette; de Brevern, Alexandre G; Camproux, Anne-Claude

    2008-04-01

    The detection of Outer Membrane Proteins (OMP) in whole genomes is an actual question, their sequence characteristics have thus been intensively studied. This class of protein displays a common beta-barrel architecture, formed by adjacent antiparallel strands. However, due to the lack of available structures, few structural studies have been made on this class of proteins. Here we propose a novel OMP local structure investigation, based on a structural alphabet approach, i.e., the decomposition of 3D structures using a library of four-residue protein fragments. The optimal decomposition of structures using hidden Markov model results in a specific structural alphabet of 20 fragments, six of them dedicated to the decomposition of beta-strands. This optimal alphabet, called SA20-OMP, is analyzed in details, in terms of local structures and transitions between fragments. It highlights a particular and strong organization of beta-strands as series of regular canonical structural fragments. The comparison with alphabets learned on globular structures indicates that the internal organization of OMP structures is more constrained than in globular structures. The analysis of OMP structures using SA20-OMP reveals some recurrent structural patterns. The preferred location of fragments in the distinct regions of the membrane is investigated. The study of pairwise specificity of fragments reveals that some contacts between structural fragments in beta-sheets are clearly favored whereas others are avoided. This contact specificity is stronger in OMP than in globular structures. Moreover, SA20-OMP also captured sequential information. This can be integrated in a scoring function for structural model ranking with very promising results. (c) 2007 Wiley-Liss, Inc.