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Sample records for partially segmented block

  1. Optimization of a partially segmented block detector for MR-compatible small animal PET

    International Nuclear Information System (INIS)

    Hwang, Ji Yeon; Chung, Yong Hyun; Baek, Cheol-Ha; An, Su Jung; Kim, Hyun-Il; Kim, Kwang Hyun

    2011-01-01

    In recent years, there has been an increasing interest in the magnetic resonance (MR)-compatible positron emission tomography (PET) scanners for both clinical and preclinical practice. The aim of this study was to design a novel PET detector module using a segmented block crystal readout with an array of multi-pixel photon counters (MPPCs). A 16.5x16.5x10.0 mm 3 LSO block was segmented into an 11x11 array, and reflective material was used to fill in the cuts to optically isolate the elements. The block was attached to a 4x4 MPPC array (Hamamatsu S11064) of 3.0x3.0 mm 2 detectors to give a total effective area of 144 mm 2 . To visualize all the individual detector elements in this 11x11 detector module, the depth of the cuts was optimized by DETECT2000 simulations. The depth of the cuts determines the spread of scintillation light onto the MPPC array. The accuracy of positioning was evaluated by varying the depth of the cuts from 0.0 to 10.0 mm in steps of 0.5 mm. A spatial resolution of 1.5 mm was achieved using the optimized partially segmented block detector. The simulation results of this study can be used effectively as a guide for parameter optimization for the development of a partially segmented block detector for high-resolution MR-compatible PET scanners.

  2. Segmented block copolymers with monodisperse aramide end-segments

    NARCIS (Netherlands)

    Araichimani, A.; Gaymans, R.J.

    2008-01-01

    Segmented block copolymers were synthesized using monodisperse diaramide (TT) as hard segments and PTMO with a molecular weight of 2 900 g · mol-1 as soft segments. The aramide: PTMO segment ratio was increased from 1:1 to 2:1 thereby changing the structure from a high molecular weight multi-block

  3. Hydrophilic segmented block copolymers based on poly(ethylene oxide) and monodisperse amide segments

    NARCIS (Netherlands)

    Husken, D.; Feijen, Jan; Gaymans, R.J.

    2007-01-01

    Segmented block copolymers based on poly(ethylene oxide) (PEO) flexible segments and monodisperse crystallizable bisester tetra-amide segments were made via a polycondensation reaction. The molecular weight of the PEO segments varied from 600 to 4600 g/mol and a bisester tetra-amide segment (T6T6T)

  4. Partial transpose of two disjoint blocks in XY spin chains

    International Nuclear Information System (INIS)

    Coser, Andrea; Tonni, Erik; Calabrese, Pasquale

    2015-01-01

    We consider the partial transpose of the spin reduced density matrix of two disjoint blocks in spin chains admitting a representation in terms of free fermions, such as XY chains. We exploit the solution of the model in terms of Majorana fermions and show that such partial transpose in the spin variables is a linear combination of four Gaussian fermionic operators. This representation allows to explicitly construct and evaluate the integer moments of the partial transpose. We numerically study critical XX and Ising chains and we show that the asymptotic results for large blocks agree with conformal field theory predictions if corrections to the scaling are properly taken into account. (paper)

  5. Partial lesions of the intratemporal segment of the facial nerve: graft versus partial reconstruction.

    Science.gov (United States)

    Bento, Ricardo F; Salomone, Raquel; Brito, Rubens; Tsuji, Robinson K; Hausen, Mariana

    2008-09-01

    In cases of partial lesions of the intratemporal segment of the facial nerve, should the surgeon perform an intraoperative partial reconstruction, or partially remove the injured segment and place a graft? We present results from partial lesion reconstruction on the intratemporal segment of the facial nerve. A retrospective study on 42 patients who presented partial lesions on the intratemporal segment of the facial nerve was performed between 1988 and 2005. The patients were divided into 3 groups based on the procedure used: interposition of the partial graft on the injured area of the nerve (group 1; 12 patients); keeping the preserved part and performing tubulization (group 2; 8 patients); and dividing the parts of the injured nerve (proximal and distal) and placing a total graft of the sural nerve (group 3; 22 patients). Fracture of the temporal bone was the most frequent cause of the lesion in all groups, followed by iatrogenic causes (p lesion of the facial nerve is still questionable. Among these 42 patients, the best results were those from the total graft of the facial nerve.

  6. Partial segmental thrombosis of the corpus cavernosum: imaging findings.

    Science.gov (United States)

    Moya-Sánchez, E; Medina-Benítez, A; Medina-Salas, V; Fernández-Navarro, L

    2018-03-05

    Partial segmental thrombosis of the corpus cavernosum is an unusual clinical condition of unknown origin that mainly affects young males, whose characteristic presentation is the appearance of unexplained perineal pain associated with a palpable perineal mass. This entity consists of thrombosis in the perineal portion of the corpus cavernosum, usually unilateral and it is associated with underlying malignant pathologies and predisposing factors such as microtrauma. After the adequate adherence to conservative treatment, the appearance of complications such as erectile dysfunction is very uncommon. Copyright © 2018 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Compatibilization of low-density polyethylene/polystyrene blends by segmented EB(PS-block-EB)(n) block copolymers

    NARCIS (Netherlands)

    Kroeze, E; ten Brinke, G.; Hadziioannou, G

    Hydrogenated segmented poly[butadiene-block-(styrene-block-butadiene)(n)] block copolymers, which were developed by use of a polymeric iniferter technique, were tested on their compatibilizing effectiveness for (10/90) LDPE/PS blends. They were found to be effective compatibilizers for this mixture,

  8. Tri-block copolymers with mono-disperse crystallizable diamide segments: synthesis, analysis and rheological properties

    NARCIS (Netherlands)

    Araichimani, A.; Gaymans, R.J.

    2008-01-01

    Tri-block copolymers with polyether mid-segments and mono-disperse amide end segments were synthesized, analyzed and some properties studied. The end segment was an aromatic diamide (diaramide, TΦB). The polyether mid-segment was a difunctional poly(tetramethylene oxide) (PTMO, 1000 and 2900 g/mol).

  9. Partially-Functionalized Isotactic Polystyrene with Blocky Comonomer Segments

    Science.gov (United States)

    Siegel, Ariel; Powers, Wayne; Ryu, Chang Y.

    2012-02-01

    Isotactic polystyrenes (iPSs) have been functionalized in solution, while the accessibility of functionalizing agent is limited by the formation of crystalline domains at various temperatures. The chemical system used is the borylated isotactic polystyrene system, and we investigated the temperature effects on reaction kinetics to ultimately control the blockiness of borylated segments in the resulting copolymer. The chemical composition of partially borylated iPS reaches a steady state that is dependent on temperature. This synthesis has been performed at many different temperatures, with different steady states being reached at different temperatures. Further analysis by differential scanning calorimetry (DSC) has shown that the higher temperature reactions have greater effect on breaking down the crystal lattice structure of the isotactic polystyrene. As a result, the lower temperature reactions affect the crystalline structure less, and the resulting copolymer has more blockiness.

  10. CO2 permeation properties of poly(ethylene oxide)-based segmented block copolymers

    NARCIS (Netherlands)

    Husken, D.; Visser, Tymen; Wessling, Matthias; Gaymans, R.J.

    2010-01-01

    This paper discusses the gas permeation properties of poly(ethylene oxide) (PEO)-based segmented block copolymers containing monodisperse amide segments. These monodisperse segments give rise to a well phase-separated morphology, comprising a continuous PEO phase with dispersed crystallised amide

  11. The melt rheological behavior of AB, ABA, BAB, and (AB)n block copolymers with monodisperse aramide segments

    NARCIS (Netherlands)

    Araichimani, A.; Dullaert, Konraad; Gaymans, R.J.

    2009-01-01

    The melt rheological behavior of segmented block copolymers with high melting diamide (A) hard segments (HS) and polyether (B) soft segments was studied. The block copolymers can be classified as B (monoblock), AB (diblock), ABA (triblock, diamide end segment), BAB (triblock, diamide mid-segment)

  12. NeuroBlocks – Visual Tracking of Segmentation and Proofreading for Large Connectomics Projects

    KAUST Repository

    Al-Awami, Ali; Beyer, Johanna; Haehn, Daniel; Kasthuri, Narayanan; Lichtman, Jeff; Pfister, Hanspeter; Hadwiger, Markus

    2015-01-01

    set, providing crucial support for the management, provenance, accountability, and auditing of large-scale segmentations. We describe the design of NeuroBlocks, starting with an analysis of the domain-specific tasks, their inherent challenges, and our

  13. Influence of chemical crosslinks on the elastic behavior of segmented block copolymers

    NARCIS (Netherlands)

    van der Schuur, J.M.; Gaymans, R.J.

    2005-01-01

    Polyether(ester–amide)s (PEEA) segmented block copolymers with di- and tri-functional poly(propylene oxide)s and amide segments were synthesized and the elastic properties studied. The difunctional polyether used had a molecular weight of 2300 g/mol end capped with 20 wt% ethylene oxide. The

  14. Hitchhiker'S Guide to Voxel Segmentation for Partial Volume Correction of in Vivo Magnetic Resonance Spectroscopy

    Directory of Open Access Journals (Sweden)

    Scott Quadrelli

    2016-01-01

    Full Text Available Partial volume effects have the potential to cause inaccuracies when quantifying metabolites using proton magnetic resonance spectroscopy (MRS. In order to correct for cerebrospinal fluid content, a spectroscopic voxel needs to be segmented according to different tissue contents. This article aims to detail how automated partial volume segmentation can be undertaken and provides a software framework for researchers to develop their own tools. While many studies have detailed the impact of partial volume correction on proton magnetic resonance spectroscopy quantification, there is a paucity of literature explaining how voxel segmentation can be achieved using freely available neuroimaging packages.

  15. Performance Evaluation of Frequency Transform Based Block Classification of Compound Image Segmentation Techniques

    Science.gov (United States)

    Selwyn, Ebenezer Juliet; Florinabel, D. Jemi

    2018-04-01

    Compound image segmentation plays a vital role in the compression of computer screen images. Computer screen images are images which are mixed with textual, graphical, or pictorial contents. In this paper, we present a comparison of two transform based block classification of compound images based on metrics like speed of classification, precision and recall rate. Block based classification approaches normally divide the compound images into fixed size blocks of non-overlapping in nature. Then frequency transform like Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) are applied over each block. Mean and standard deviation are computed for each 8 × 8 block and are used as features set to classify the compound images into text/graphics and picture/background block. The classification accuracy of block classification based segmentation techniques are measured by evaluation metrics like precision and recall rate. Compound images of smooth background and complex background images containing text of varying size, colour and orientation are considered for testing. Experimental evidence shows that the DWT based segmentation provides significant improvement in recall rate and precision rate approximately 2.3% than DCT based segmentation with an increase in block classification time for both smooth and complex background images.

  16. Gravel Image Segmentation in Noisy Background Based on Partial Entropy Method

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Because of wide variation in gray levels and particle dimensions and the presence of many small gravel objects in the background, as well as corrupting the image by noise, it is difficult o segment gravel objects. In this paper, we develop a partial entropy method and succeed to realize gravel objects segmentation. We give entropy principles and fur calculation methods. Moreover, we use minimum entropy error automaticly to select a threshold to segment image. We introduce the filter method using mathematical morphology. The segment experiments are performed by using different window dimensions for a group of gravel image and demonstrates that this method has high segmentation rate and low noise sensitivity.

  17. [Pharmacology of local anesthetics and clinical aspects of segmental blocking. II. Spinal anesthesia].

    Science.gov (United States)

    Kozlov, S P; Svetlov, V A; Luk'ianov, M V

    1998-01-01

    Clinical picture of development of segmental blocking after subarachnoidal injection of hyperbaric solutions of 0.75% bupivacaine, 5% ultracaine, and isobaric 0.5% bupivacaine is studied. A total of 152 patients operated on the lower part of the body and the lower limbs were examined under conditions of single, prolonged subarachnoidal, and combined spinal epidural anesthesia. Ultracaine and bupivacaine in different concentrations with different barism provided anesthesia equivalent by the efficacy, depth, and dissemination of sensory block. Segmental blocking with 5% ultracaine was characterized by the shortest latent period (3.14 +/- 0.16 min, p anesthesia in comparison with a single injection, and combined spinal epidural anesthesia shortened the latent period of segmental blocking and ensured intraoperative anesthesia and postoperative analgesia at the expense of the epidural component.

  18. [Evaluation of Image Quality of Readout Segmented EPI with Readout Partial Fourier Technique].

    Science.gov (United States)

    Yoshimura, Yuuki; Suzuki, Daisuke; Miyahara, Kanae

    Readout segmented EPI (readout segmentation of long variable echo-trains: RESOLVE) segmented k-space in the readout direction. By using the partial Fourier method in the readout direction, the imaging time was shortened. However, the influence on image quality due to insufficient data sampling is concerned. The setting of the partial Fourier method in the readout direction in each segment was changed. Then, we examined signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and distortion ratio for changes in image quality due to differences in data sampling. As the number of sampling segments decreased, SNR and CNR showed a low value. In addition, the distortion ratio did not change. The image quality of minimum sampling segments is greatly different from full data sampling, and caution is required when using it.

  19. Poly(ether amide) segmented block copolymers with adipicacid based tetra amide segments

    NARCIS (Netherlands)

    Biemond, G.J.E.; Feijen, Jan; Gaymans, R.J.

    2007-01-01

    Poly(tetramethylene oxide)-based poly(ether ester amide)s with monodisperse tetraamide segments were synthesized. The tetraamide segment was based on adipic acid, terephthalic acid, and hexamethylenediamine. The synthesis method of the copolymers and the influence of the tetraamide concentration,

  20. Diagnostic lumbosacral segmental nerve blocks with local anesthetics: a prospective double-blind study on the variability and interpretation of segmental effects.

    NARCIS (Netherlands)

    Wolff, A.P.; Groen, G.J.; Crul, B.J.P.

    2001-01-01

    BACKGROUND AND OBJECTIVES: Selective spinal nerve infiltration blocks are used diagnostically in patients with chronic low back pain radiating into the leg. Generally, a segmental nerve block is considered successful if the pain is reduced substantially. Hypesthesia and elicited paresthesias

  1. Intradomain phase transitions in flexible block copolymers with self-aligning segments

    Science.gov (United States)

    Burke, Christopher J.; Grason, Gregory M.

    2018-05-01

    We study a model of flexible block copolymers (BCPs) in which there is an enlthalpic preference for orientational order, or local alignment, among like-block segments. We describe a generalization of the self-consistent field theory of flexible BCPs to include inter-segment orientational interactions via a Landau-de Gennes free energy associated with a polar or nematic order parameter for segments of one component of a diblock copolymer. We study the equilibrium states of this model numerically, using a pseudo-spectral approach to solve for chain conformation statistics in the presence of a self-consistent torque generated by inter-segment alignment forces. Applying this theory to the structure of lamellar domains composed of symmetric diblocks possessing a single block of "self-aligning" polar segments, we show the emergence of spatially complex segment order parameters (segment director fields) within a given lamellar domain. Because BCP phase separation gives rise to spatially inhomogeneous orientation order of segments even in the absence of explicit intra-segment aligning forces, the director fields of BCPs, as well as thermodynamics of lamellar domain formation, exhibit a highly non-linear dependence on both the inter-block segregation (χN) and the enthalpy of alignment (ɛ). Specifically, we predict the stability of new phases of lamellar order in which distinct regions of alignment coexist within the single mesodomain and spontaneously break the symmetries of the lamella (or smectic) pattern of composition in the melt via in-plane tilt of the director in the centers of the like-composition domains. We further show that, in analogy to Freedericksz transition confined nematics, the elastic costs to reorient segments within the domain, as described by the Frank elasticity of the director, increase the threshold value ɛ needed to induce this intra-domain phase transition.

  2. NeuroBlocks – Visual Tracking of Segmentation and Proofreading for Large Connectomics Projects

    KAUST Repository

    Al-Awami, Ali

    2015-08-12

    In the field of connectomics, neuroscientists acquire electron microscopy volumes at nanometer resolution in order to reconstruct a detailed wiring diagram of the neurons in the brain. The resulting image volumes, which often are hundreds of terabytes in size, need to be segmented to identify cell boundaries, synapses, and important cell organelles. However, the segmentation process of a single volume is very complex, time-intensive, and usually performed using a diverse set of tools and many users. To tackle the associated challenges, this paper presents NeuroBlocks, which is a novel visualization system for tracking the state, progress, and evolution of very large volumetric segmentation data in neuroscience. NeuroBlocks is a multi-user web-based application that seamlessly integrates the diverse set of tools that neuroscientists currently use for manual and semi-automatic segmentation, proofreading, visualization, and analysis. NeuroBlocks is the first system that integrates this heterogeneous tool set, providing crucial support for the management, provenance, accountability, and auditing of large-scale segmentations. We describe the design of NeuroBlocks, starting with an analysis of the domain-specific tasks, their inherent challenges, and our subsequent task abstraction and visual representation. We demonstrate the utility of our design based on two case studies that focus on different user roles and their respective requirements for performing and tracking the progress of segmentation and proofreading in a large real-world connectomics project.

  3. Segmentation, Inference and Classification of Partially Overlapping Nanoparticles

    KAUST Repository

    Chiwoo Park,

    2013-03-01

    This paper presents a method that enables automated morphology analysis of partially overlapping nanoparticles in electron micrographs. In the undertaking of morphology analysis, three tasks appear necessary: separate individual particles from an agglomerate of overlapping nano-objects; infer the particle\\'s missing contours; and ultimately, classify the particles by shape based on their complete contours. Our specific method adopts a two-stage approach: the first stage executes the task of particle separation, and the second stage conducts simultaneously the tasks of contour inference and shape classification. For the first stage, a modified ultimate erosion process is developed for decomposing a mixture of particles into markers, and then, an edge-to-marker association method is proposed to identify the set of evidences that eventually delineate individual objects. We also provided theoretical justification regarding the separation capability of the first stage. In the second stage, the set of evidences become inputs to a Gaussian mixture model on B-splines, the solution of which leads to the joint learning of the missing contour and the particle shape. Using twelve real electron micrographs of overlapping nanoparticles, we compare the proposed method with seven state-of-the-art methods. The results show the superiority of the proposed method in terms of particle recognition rate.

  4. Small-angle neutron scattering of short-segment block polymers

    International Nuclear Information System (INIS)

    Cooper, S.L.; Miller, J.A.; Homan, J.G.

    1988-01-01

    Small-angle neutron scattering has been used to investigate the chain conformation of the hard and soft segments in short-segment polyether-polyester and polyether-polyurethane materials. The method of phase-contrast matching was used to eliminate the coherent neutron scattering due to the two-phase microstructure in these materials. The partial deutero-labelling necessary for this technique also provides a neutron scattering contrast between labelled and unlabelled segments. The structure factor for each segment type is determined from the coherent scattering from such deuterolabelled materials. In all of the materials examined, the poly(tetramethylene oxide) (PTMO) soft segment was found to be in a slightly extended conformation relative to bulk PTMO at room temperature. Upon heating, the PTMO segments contracted to a more relaxed conformation. In one polyether-polyurethane sample, the radius of gyration of the PTMO segment increased again at high temperatures, indicating phase mixing. The hardsegment radii of gyration in the polyether-polyester materials were found to increase with temperature, indicating a transition from a chain-folded conformation at room temperature to a more extended conformation at higher temperatures. The radius of gyration of the whole polyether-polyester chain first decreased then increased with temperature, indicative of the combined effects of the component hard- and soft-segment chain conformation changes. The hard-segment radius of gyration in a polyether-polyurethane was observed to decrease with temperature. (orig.)

  5. Minimal Blocking Sets in PG(2, 8) and Maximal Partial Spreads in PG(3, 8)

    DEFF Research Database (Denmark)

    Barat, Janos

    2004-01-01

    We prove that PG(2, 8) does not contain minimal blocking sets of size 14. Using this result we prove that 58 is the largest size for a maximal partial spread of PG(3, 8). This supports the conjecture that q2-q+ 2 is the largest size for a maximal partial spread of PG(3, q), q>7....

  6. Staining pattern classification of antinuclear autoantibodies based on block segmentation in indirect immunofluorescence images.

    Directory of Open Access Journals (Sweden)

    Jiaqian Li

    Full Text Available Indirect immunofluorescence based on HEp-2 cell substrate is the most commonly used staining method for antinuclear autoantibodies associated with different types of autoimmune pathologies. The aim of this paper is to design an automatic system to identify the staining patterns based on block segmentation compared to the cell segmentation most used in previous research. Various feature descriptors and classifiers are tested and compared in the classification of the staining pattern of blocks and it is found that the technique of the combination of the local binary pattern and the k-nearest neighbor algorithm achieve the best performance. Relying on the results of block pattern classification, experiments on the whole images show that classifier fusion rules are able to identify the staining patterns of the whole well (specimen image with a total accuracy of about 94.62%.

  7. Adaptive block online learning target tracking based on super pixel segmentation

    Science.gov (United States)

    Cheng, Yue; Li, Jianzeng

    2018-04-01

    Video target tracking technology under the unremitting exploration of predecessors has made big progress, but there are still lots of problems not solved. This paper proposed a new algorithm of target tracking based on image segmentation technology. Firstly we divide the selected region using simple linear iterative clustering (SLIC) algorithm, after that, we block the area with the improved density-based spatial clustering of applications with noise (DBSCAN) clustering algorithm. Each sub-block independently trained classifier and tracked, then the algorithm ignore the failed tracking sub-block while reintegrate the rest of the sub-blocks into tracking box to complete the target tracking. The experimental results show that our algorithm can work effectively under occlusion interference, rotation change, scale change and many other problems in target tracking compared with the current mainstream algorithms.

  8. Teenage patients with ingrown toenails: Treatment with partial matrix excision or segmental phenolization

    Directory of Open Access Journals (Sweden)

    Murat Korkmaz

    2013-01-01

    Full Text Available Background: Ingrown toenails (IT is a very common problem leading to significant associated morbidity. The articles related to phenolization for matrix removal in teenagers with IT are not enough in the foot surgery literature. Aims: To compare the postoperative recovery periods, complication rate, and tolerability of partial matrix excision and segmental phenolization in teenagers with IT. Materials and Methods: Thirty-nine patients (13-17 years with 48 IT were randomly divided into two groups and were treated with partial matrix excision (Group I and segmental phenolization (Group II. We assessed the recurrence rates, postoperative complications, duration of analgesic usage, and time to return to daily activities. Results: There was no significant difference between the demographic and clinical data of the two groups. Three patients in Group I and two patients in Group II experienced moderate pain postoperatively. These patients used analgesics for 3 days. The rates of postoperative complications and recurrences between the two groups showed no statistically significant difference ( P = 0.688. The time to return to normal daily activities was significantly shorter in Group II patients than in Group I patients ( P < 0.05. Conclusions: Partial matrix excision is a very safe model of therapy in the surgical treatment of teenagers with IT. It has low recurrence rate and minimal postoperative morbidity. We concluded that segmental phenolization is also as safe as partial matrix excision in the treatment of IT and patients return to their daily activities in less time with this treatment modality.

  9. H-Seda: Partial Packet Recovery with Heterogeneous Block Sizes for Wireless Sensor Networks

    KAUST Repository

    Meer, Ammar M.

    2012-12-08

    Wireless sensor networks (WSN) have been largely used in various applications due to its ease of deployment and scalability. The throughput of such networks, however, suffers from high bit error rates mainly because of medium characteristics. Maximizing bandwidth utilization while maintaining low frame error rate has been an interesting problem. Frame fragmentation into small blocks with dedicated error detection codes per block can reduce the unnecessary retransmission of the correctly received blocks. The optimal block size, however, varies based on the wireless channel conditions. In addition, blocks within a frame can have different optimal sizes based on the variations on interference patterns. This thesis studies two dynamic partial packet recovery approaches experimentally over several interference intensities with various transmission-power levels. It also proposes a dynamic data link layer protocol: Hybrid Seda (H-Seda). H-Seda effectively addresses the challenges associated with dynamic partitioning of blocks while taking the observed error patterns into consideration. The design of H-Seda is discussed in details and compared to other previous approaches, namely Seda+ and Seda. The implementation of H-Seda shows substantial enhancements over fixed-size partial packet recovery protocols, achieving up to 2.5x improvement in throughput when the channel condition is noisy, while delay experienced decreases to only 14 % of the delay observed in Seda. On average, it shows 35% gain in goodput across all channel conditions used in our experiments. This significant improvement is due to the selective nature of H-Seda which minimizes retransmission overhead by selecting the appropriate number of blocks in each data frame. Additionally, H-Seda successfully reduces block overhead by 50% through removing block number field reaching to better performance when channel conditions are identical.

  10. Three-dimensional renal CT angiography for guiding segmental renal artery clamping during laparoscopic partial nephrectomy

    International Nuclear Information System (INIS)

    Xu, Yi; Shao, Pengfei; Zhu, Xiaomei; Lv, Qiang; Liu, Wangyan; Xu, Hai; Zhu, Yinsu; Yang, Guangyu; Tang, Lijun; Yin, Changjun

    2013-01-01

    Aim: To evaluate the effectiveness of three-dimensional (3D) renal computed tomography angiography (CTA) in guiding segmental renal artery clamping during laparoscopic partial nephrectomy (LPN). Materials and methods: Forty-three patients with renal tumours undergoing renal CTA before LPN were retrospectively enrolled in this study. 3D arteriogram reconstructed images were created to identify the renal tumour-supplying arteries. The number and location of these targeted vessels were annotated on 3D images preoperatively and compared with the clamped vessels during LPN. The consistency between target vessels annotated at CTA and clamped arteries at LPN was compared both using a patient-based analysis and vessel-based analysis. The χ 2 test was applied to analyse the influence of tumour size, location, and growth pattern on the number of clamped segmental renal branches. Results: On patient-based analysis, the number of targeted vessels was consistent with the clamped vessels during LPN in 33 of 43 patients. On vessel-based analysis, 56 of 65 target vessels annotated at CTA were clamped during LPN. More segmental renal branches (p = 0.04) were clamped in patients with tumours of larger size. Tumour location and growth pattern had no association with the number of clamped segmental branches during LPN. Conclusion: High-quality CTA images and 3D reconstruction images can detect detailed information of tumour-supplying arteries to renal tumours. 3D renal CTA is an effective way to guide segmental renal artery clamping during LPN

  11. Influence of needle position on lumbar segmental nerve root block selectivity.

    Science.gov (United States)

    Wolff, André P; Groen, Gerbrand J; Wilder-Smith, Oliver H

    2006-01-01

    In patients with chronic low back pain radiating to the leg, segmental nerve root blocks (SNRBs) are performed to predict surgical outcome and identify the putative symptomatic spinal nerve. Epidural spread may lead to false interpretation, affecting clinical decision making. Systematic fluoroscopic analysis of epidural local anesthetic spread and its relationship to needle tip location has not been published to date. Study aims include assessment of epidural local anesthetic spread and its relationship to needle position during fluoroscopy-assisted blocks. Patients scheduled for L4, L5, and S1 blocks were included in this prospective observational study. Under fluoroscopy and electrostimulation, they received 0.5 mL of a mixture containing lidocaine 5 mg and iohexol 75 mg. X-rays with needle tip and contrast were scored for no epidural spread (grade 0), local spread epidurally (grade 1), or to adjacent nerve roots (grade 2). Sixty-five patients were analyzed for epidural spread, 62 for needle position. Grade 1 epidural spread occurred in 47% of L4 and 28% of L5 blocks and grade 2 spread in 3 blocks (5%; L5 n = 1, S1 n = 2). For lumbar blocks, the needle was most frequently found in the lateral upper half of the intervertebral foramen. Epidural spread occurred more frequently with medial needle positions (P = .06). The findings suggest (P = .06) that the risk of grade 1 and 2 lumbar epidural spread, which results in decreased SNRB selectivity, is greater with medial needle positions in the intervertebral foramen. The variability in anatomic position of the dorsal root ganglion necessitates electrostimulation to guide SNRB in addition to fluoroscopy.

  12. A Partial Proportional Odds Model for Pedestrian Crashes at Mid-Blocks in Melbourne Metropolitan Area

    Directory of Open Access Journals (Sweden)

    Toran Pour Alireza

    2016-01-01

    Full Text Available Pedestrian crashes account for 11% of all reported traffic crashes in Melbourne metropolitan area between 2004 and 2013. There are very limited studies on pedestrian accidents at mid-blocks. Mid-block crashes account for about 46% of the total pedestrian crashes in Melbourne metropolitan area. Meanwhile, about 50% of all pedestrian fatalities occur at mid-blocks. In this research, Partial Proportional Odds (PPO model is applied to examine vehicle-pedestrian crash severity at mid-blocks in Melbourne metropolitan area. The PPO model is a logistic regression model that allows the covariates that meet the proportional odds assumption to affect different crash severity levels with the same magnitude; whereas the covariates that do not meet the proportional odds assumption can have different effects on different severity levels. In this research vehicle-pedestrian crashes at mid-blocks are analysed for first time. In addition, some factors such as distance of crashes to public transport stops, average road slope and some social characteristics are considered to develop the model in this research for first time. Results of PPO model show that speed limit, light condition, pedestrian age and gender, and vehicle type are the most significant factors that influence vehicle-pedestrian crash severity at mid-blocks.

  13. Robustness, Death of Spiral Wave in the Network of Neurons under Partial Ion Channel Block

    International Nuclear Information System (INIS)

    Jun, Ma; Long, Huang; Chun-Ni, Wang; Zhong-Sheng, Pu

    2013-01-01

    The development of spiral wave in a two-dimensional square array due to partial ion channel block (Potassium, Sodium) is investigated, the dynamics of the node is described by Hodgkin—Huxley neuron and these neurons are coupled with nearest neighbor connection. The parameter ratio x Na (and x K ), which defines the ratio of working ion channel number of sodium (potassium) to the total ion channel number of sodium (and potassium), is used to measure the shift conductance induced by channel block. The distribution of statistical variable R in the two-parameter phase space (parameter ratio vs. poisoning area) is extensively calculated to mark the parameter region for transition of spiral wave induced by partial ion channel block, the area with smaller factors of synchronization R is associated the parameter region that spiral wave keeps alive and robust to the channel poisoning. Spiral wave keeps alive when the poisoned area (potassium or sodium) and degree of intoxication are small, distinct transition (death, several spiral waves coexist or multi-arm spiral wave emergence) occurs under moderate ratio x Na (and x K ) when the size of blocked area exceeds certain thresholds. Breakup of spiral wave occurs and multi-arm of spiral waves are observed when the channel noise is considered. (interdisciplinary physics and related areas of science and technology)

  14. [Effects of gap junction blocking on the oxygen partial pressure in acupoints of the bladder meridian].

    Science.gov (United States)

    Wang, Qi; Yu, Wei-Chang; Jiang, Hong-Zhi; Chen, Sheng-Li; Zhang, Ming-Min; Kong, E-Sheng; Huang, Guang-Ying

    2010-12-01

    To explore the relation between gap junction and meridian phenomenon. The oxygen partial pressure in acupoints [see text for formula] and in their corresponding non-acupoints of the Bladder Meridian was observed with the needle-type tissue oxygen tension sensor in the gap junction blocking goats by 1-Heptanol injection and the Connexin 43 (Cx43) gene knockout mice. (1) The oxygen partial pressure in acupoints of Bladder Meridian on goats was higher than that in non-acupoints after 1-Heptanol injection with significant differences between them (both P oxygen partial pressure in acupoints of Bladder Meridian on goats increased significantly after injecting 1-Heptanol as compare with that either injecting normal saline or injecting nothing with significant differences between them (all P oxygen partial pressure in acupoints of the Bladder Meridian was significantly higher than that in the non-acupoint controls in Cx43 wild type (WT) mice (all P oxygen partial pressure between acupoints and non-acupoint controls showed no significant differences (all P > 0.05). (4) In acupoints, the oxygen partial pressure in Cx43 WT mice was significantly higher than that in Cx43 HT mice (all P 0.05). Gap junction maybe the essential factor in signal transduction of acupuncture.

  15. Partial PIC-MRC Receiver Design for Single Carrier Block Transmission System over Multipath Fading Channels

    Directory of Open Access Journals (Sweden)

    Juinn-Horng Deng

    2012-01-01

    Full Text Available Single carrier block transmission (SCBT system has become one of the most popular modulation systems due to its low peak-to-average power ratio (PAPR, and it is gradually considered to be used for uplink wireless communication systems. In this paper, a low complexity partial parallel interference cancellation (PIC with maximum ratio combining (MRC technology is proposed to use for receiver to combat the intersymbol interference (ISI problem over multipath fading channel. With the aid of MRC scheme, the proposed partial PIC technique can effectively perform the interference cancellation and acquire the benefit of time diversity gain. Finally, the proposed system can be extended to use for multiple antenna systems to provide excellent performance. Simulation results reveal that the proposed low complexity partial PIC-MRC SIMO system can provide robust performance and outperform the conventional PIC and the iterative frequency domain decision feedback equalizer (FD-DFE systems over multipath fading channel environment.

  16. Simulation-based partial volume correction for dopaminergic PET imaging. Impact of segmentation accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Rong, Ye; Winz, Oliver H. [University Hospital Aachen (Germany). Dept. of Nuclear Medicine; Vernaleken, Ingo [University Hospital Aachen (Germany). Dept. of Psychiatry, Psychotherapy and Psychosomatics; Goedicke, Andreas [University Hospital Aachen (Germany). Dept. of Nuclear Medicine; High Tech Campus, Philips Research Lab., Eindhoven (Netherlands); Mottaghy, Felix M. [University Hospital Aachen (Germany). Dept. of Nuclear Medicine; Maastricht University Medical Center (Netherlands). Dept. of Nuclear Medicine; Rota Kops, Elena [Forschungszentrum Juelich (Germany). Inst. of Neuroscience and Medicine-4

    2015-07-01

    Partial volume correction (PVC) is an essential step for quantitative positron emission tomography (PET). In the present study, PVELab, a freely available software, is evaluated for PVC in {sup 18}F-FDOPA brain-PET, with a special focus on the accuracy degradation introduced by various MR-based segmentation approaches. Methods Four PVC algorithms (M-PVC; MG-PVC; mMG-PVC; and R-PVC) were analyzed on simulated {sup 18}F-FDOPA brain-PET images. MR image segmentation was carried out using FSL (FMRIB Software Library) and SPM (Statistical Parametric Mapping) packages, including additional adaptation for subcortical regions (SPM{sub L}). Different PVC and segmentation combinations were compared with respect to deviations in regional activity values and time-activity curves (TACs) of the occipital cortex (OCC), caudate nucleus (CN), and putamen (PUT). Additionally, the PVC impact on the determination of the influx constant (K{sub i}) was assessed. Results Main differences between tissue-maps returned by three segmentation algorithms were found in the subcortical region, especially at PUT. Average misclassification errors in combination with volume reduction was found to be lowest for SPM{sub L} (PUT < 30%) and highest for FSL (PUT > 70%). Accurate recovery of activity data at OCC is achieved by M-PVC (apparent recovery coefficient varies between 0.99 and 1.10). The other three evaluated PVC algorithms have demonstrated to be more suitable for subcortical regions with MG-PVC and mMG-PVC being less prone to the largest tissue misclassification error simulated in this study. Except for M-PVC, quantification accuracy of K{sub i} for CN and PUT was clearly improved by PVC. Conclusions The regional activity value of PUT was appreciably overcorrected by most of the PVC approaches employing FSL or SPM segmentation, revealing the importance of accurate MR image segmentation for the presented PVC framework. The selection of a PVC approach should be adapted to the anatomical

  17. Multiblock copolymers with highly sulfonated blocks containing di- and tetrasulfonated arylene sulfone segments for proton exchange membrane fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Takamuku, Shogo; Jannasch, Patric [Polymer and Materials Chemistry, Department of Chemistry, Lund University (Sweden)

    2012-01-15

    Multiblock copoly(arylene ether sulfone)s with different block lengths and ionic contents are tailored for durable and proton-conducting electrolyte membranes. Two series of fully aromatic copolymers are prepared by coupling reactions between non-sulfonated hydrophobic precursor blocks and highly sulfonated hydrophilic precursor blocks containing either fully disulfonated diarylsulfone or fully tetrasulfonated tetraaryldisulfone segments. The sulfonic acid groups are exclusively introduced in ortho positions to the sulfone bridges to impede desulfonation reactions and give the blocks ion exchange capacities (IECs) of 4.1 and 4.6 meq. g{sup -1}, respectively. Solvent cast block copolymer membranes show well-connected hydrophilic nanophase domains for proton transport and high decomposition temperatures above 310 C under air. Despite higher IEC values, membranes containing tetrasulfonated tetraaryldisulfone segments display a markedly lower water uptake than the corresponding ones with disulfonated diarylsulfone segments when immersed in water at 100 C, presumably because of the much higher chain stiffness and glass transition temperature of the former segments. The former membranes have proton conductivities in level of a perfluorosulfonic acid membrane (NRE212) under fully humidified conditions. A membrane with an IEC of 1.83 meq. g{sup -1} reaches above 6 mS cm{sup -1} under 30% relative humidity at 80 C, to be compared with 10 mS cm{sup -1} for NRE212 under the same conditions. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Diagnostic lumbosacral segmental nerve blocks with local anesthetics: a prospective double-blind study on the variability and interpretation of segmental effects.

    Science.gov (United States)

    Wolff, A P; Groen, G J; Crul, B J

    2001-01-01

    Selective spinal nerve infiltration blocks are used diagnostically in patients with chronic low back pain radiating into the leg. Generally, a segmental nerve block is considered successful if the pain is reduced substantially. Hypesthesia and elicited paresthesias coinciding with the presumed segmental level are used as controls. The interpretation depends on a standard dermatomal map. However, it is not clear if this interpretation is reliable enough, because standard dermatomal maps do not show the overlap of neighboring dermatomes. The goal of the present study is to establish if dissimilarities exist between areas of hypesthesia, spontaneous pain reported by the patient, pain reduction by local anesthetics, and paresthesias elicited by sensory electrostimulation. A secondary goal is to determine to what extent the interpretation is improved when the overlaps of neighboring dermatomes are taken into account. Patients suffering from chronic low back pain with pain radiating into the leg underwent lumbosacral segmental nerve root blocks at subsequent levels on separate days. Lidocaine (2%, 0.5 mL) mixed with radiopaque fluid (0.25 mL) was injected after verifying the target location using sensory and motor electrostimulation. Sensory changes (pinprick method), paresthesias (reported by the patient), and pain reduction (Numeric Rating Scale) were reported. Hypesthesia and paresthesias were registered in a standard dermatomal map and in an adapted map which included overlap of neighboring dermatomes. The relationships between spinal level of injection, extent of hypesthesia, location of paresthesias, and corresponding dermatome were assessed quantitatively. Comparison of the results between both dermatomal maps was done by paired t-tests. After inclusion, data were processed for 40 segmental nerve blocks (L2-S1) performed in 29 patients. Pain reduction was achieved in 43%. Hypesthetic areas showed a large variability in size and location, and also in comparison to

  19. Effects of fuel relocation on reflood in a partially-blocked rod bundle

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byoung Jae [School of Mechanical Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134 (Korea, Republic of); Kim, Jongrok; Kim, Kihwan; Bae, Sung Won [Thermal-Hydraulic Safety Research Division, Korea Atomic Energy Research Division, 111 Daedeok-daero, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Moon, Sang-Ki, E-mail: skmoon@kaeri.re.kr [Thermal-Hydraulic Safety Research Division, Korea Atomic Energy Research Division, 111 Daedeok-daero, Yuseong-gu, Daejeon 34057 (Korea, Republic of)

    2017-02-15

    Ballooning of the fuel rods has been an important issue, since it can influence the coolability of the rod bundle in a large-break loss-of-coolant accident (LBLOCA). Numerous past studies have investigated the effect of blockage geometry on the heat transfer in a partially blocked rod bundle. However, they did not consider the occurrence of fuel relocation and the corresponding effect on two-phase heat transfer. Some fragmented fuel particles located above the ballooned region may drop into the enlarged volume of the balloon. Accordingly, the fuel relocation brings in a local power increase in the ballooned region. The present study’s objective is to investigate the effect of the fuel relocation on the reflood under a LBLOCA condition. Toward this end, experiments were performed in a 5 × 5 partially-blocked rod bundle. Two power profiles were tested: one is a typical cosine shape and the other is the modified shape considering the effect of the fuel relocation. For a typical power shape, the peak temperature in the ballooned rods was lower than that in the intact rods. On the other hand, for the modified power shape, the peak temperature in the ballooned rods was higher than that in the intact rods. Numerical simulations were also performed using the MARS code. The tendencies of the peak clad temperatures were well predicted.

  20. Repair of segmental load-bearing bone defect by autologous mesenchymal stem cells and plasma-derived fibrin impregnated ceramic block results in early recovery of limb function.

    Science.gov (United States)

    Ng, Min Hwei; Duski, Suryasmi; Tan, Kok Keong; Yusof, Mohd Reusmaazran; Low, Kiat Cheong; Rose, Isa Mohamed; Mohamed, Zahiah; Bin Saim, Aminuddin; Idrus, Ruszymah Bt Hj

    2014-01-01

    Calcium phosphate-based bone substitutes have not been used to repair load-bearing bone defects due to their weak mechanical property. In this study, we reevaluated the functional outcomes of combining ceramic block with osteogenic-induced mesenchymal stem cells and platelet-rich plasma (TEB) to repair critical-sized segmental tibial defect. Comparisons were made with fresh marrow-impregnated ceramic block (MIC) and partially demineralized allogeneic bone block (ALLO). Six New Zealand White female rabbits were used in each study group and three rabbits with no implants were used as negative controls. By Day 90, 4/6 rabbits in TEB group and 2/6 in ALLO and MIC groups resumed normal gait pattern. Union was achieved significantly faster in TEB group with a radiological score of 4.50 ± 0.78 versus ALLO (1.06 ± 0.32), MIC (1.28 ± 0.24), and negative controls (0). Histologically, TEB group scored the highest percentage of new bone (82% ± 5.1%) compared to ALLO (5% ± 2.5%) and MIC (26% ± 5.2%). Biomechanically, TEB-treated tibiae achieved the highest compressive strength (43.50 ± 12.72 MPa) compared to those treated with ALLO (15.15 ± 3.57 MPa) and MIC (23.28 ± 6.14 MPa). In conclusion, TEB can repair critical-sized segmental load-bearing bone defects and restore limb function.

  1. CFD analysis of blockage length on a partially blocked fuel rod

    International Nuclear Information System (INIS)

    Scuro, Nikolas Lymberis; Andrade, Delvonei Alves de; Angelo, Gabriel; Angelo, Edvaldo

    2017-01-01

    In LOCA accidents, fuel rods may balloon by the increasing of pressure difference between fuel rod and core vessel. With the balloon effect, the swelling can partially block the flow channel, affecting the coolability during reflood phase. In order to analyze the influence of blockage length after LOCA events, many numerical simulations using Ansys-CFX code have been done in steady state condition, characterizing the final phase of reflood. Peaks of temperature are observed in the middle of the fuel rod, followed by a temperature drop. This effect is justified by the increasing of heat transfer coefficient, originated from the high turbulence effects. Therefore, this paper considers a radial blockage of 90%, varying just the blockage length. This study observed that, for the same boundary conditions, the longer the blockage length originated after LOCA events, the higher are the central temperatures in the fuel rod. (author)

  2. CFD analysis of blockage length on a partially blocked fuel rod

    Energy Technology Data Exchange (ETDEWEB)

    Scuro, Nikolas Lymberis; Andrade, Delvonei Alves de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Engenharia Nuclear; Angelo, Gabriel [Centro Universitário FEI (UNIFEI), São Paulo, SP (Brazil). Dept. de Engenharia Mecânica; Angelo, Edvaldo, E-mail: nikolas.scuro@gmail.com, E-mail: delvonei@ipen.br, E-mail: gangelo@fei.edu.br, E-mail: eangelo@mackenzie.br [Universidade Presbiteriana Mackenzie, São Paulo, SP (Brazil). Escola da Engenharia. Grupo de Simulação Numérica

    2017-07-01

    In LOCA accidents, fuel rods may balloon by the increasing of pressure difference between fuel rod and core vessel. With the balloon effect, the swelling can partially block the flow channel, affecting the coolability during reflood phase. In order to analyze the influence of blockage length after LOCA events, many numerical simulations using Ansys-CFX code have been done in steady state condition, characterizing the final phase of reflood. Peaks of temperature are observed in the middle of the fuel rod, followed by a temperature drop. This effect is justified by the increasing of heat transfer coefficient, originated from the high turbulence effects. Therefore, this paper considers a radial blockage of 90%, varying just the blockage length. This study observed that, for the same boundary conditions, the longer the blockage length originated after LOCA events, the higher are the central temperatures in the fuel rod. (author)

  3. Computation of 3D thermohydraulics in partially blocked bundles during the reflood phase of a LOCA

    International Nuclear Information System (INIS)

    Cicero, G.M.; Briere, E.; Fornaciari, G.

    1994-06-01

    In Pressurized Water Reactors (PWR), ballooning of the fuel rod claddings may occur during a LOCA, since the fuel rod claddings are heated up, and the system pressure is low. The severe blockages that may result induce cross-flow diversion and three-dimensional effects on thermohydraulics in the core bundle, during the reflood phase. To improve the knowledge of these phenomena and their physical modelling in the code CATHARE, 3D computer codes are needed. In 1990, EDF has started up a development and validation program of the 3D THYC computer code to analyze the thermohydraulics of the flow during the reflood phase, in partially blocked bundles. The main objective is to calculate the temperatures of the rods above the quench front, when they are cooled by superheated steam with saturated droplets. First, this paper introduces the THYC model developed for reflood studies. Secondly, we report the first qualification results on a Flooding Experiments with Blocked Array (FEBA) test. Thirdly, we analyze the model predictions on a large break LOCA transient, in a 900 MW PWR 11x11 core area with a 3x3 central blockage. THYC simulates the transient in the bundle around and above the blockage, until the quench front enters the computational domain. Previously, a 1D CATHARE simulation gives the boundary conditions and, in the reactor core case, the deformation of the blocked fuel rods. The results analysis focused on the time evolution of the clad temperatures in the blocked and in the bypass region. In the FEBA test simulation, the main observations are properly predicted within the blockage. Temperatures are lower in blocked rod sleeves than in unblocked rod claddings since the steam gap reduces the power transmitted by the heater rod to the sleeve. In the core case, the model predicts the opposite result. Within the blockage, ballooned rod temperatures are higher than non-ballooned rod ones. We show by sensitivity studies that these behaviour difference between FEBA rods

  4. A fast direct method for block triangular Toeplitz-like with tri-diagonal block systems from time-fractional partial differential equations

    Science.gov (United States)

    Ke, Rihuan; Ng, Michael K.; Sun, Hai-Wei

    2015-12-01

    In this paper, we study the block lower triangular Toeplitz-like with tri-diagonal blocks system which arises from the time-fractional partial differential equation. Existing fast numerical solver (e.g., fast approximate inversion method) cannot handle such linear system as the main diagonal blocks are different. The main contribution of this paper is to propose a fast direct method for solving this linear system, and to illustrate that the proposed method is much faster than the classical block forward substitution method for solving this linear system. Our idea is based on the divide-and-conquer strategy and together with the fast Fourier transforms for calculating Toeplitz matrix-vector multiplication. The complexity needs O (MNlog2 ⁡ M) arithmetic operations, where M is the number of blocks (the number of time steps) in the system and N is the size (number of spatial grid points) of each block. Numerical examples from the finite difference discretization of time-fractional partial differential equations are also given to demonstrate the efficiency of the proposed method.

  5. High-degree atrioventricular block complicating ST-segment elevation myocardial infarction in the era of primary percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Gang, Uffe Jakob Ortved; Hvelplund, Anders; Pedersen, Sune

    2012-01-01

    Primary percutaneous coronary intervention (pPCI) has replaced thrombolysis as treatment-of-choice for ST-segment elevation myocardial infarction (STEMI). However, the incidence and prognostic significance of high-degree atrioventricular block (HAVB) in STEMI patients in the pPCI era has been only...... sparsely investigated. The objective of this study was to assess the incidence, predictors and prognostic significance of HAVB in STEMI patients treated with pPCI....

  6. A Virtual Reality System for PTCD Simulation Using Direct Visuo-Haptic Rendering of Partially Segmented Image Data.

    Science.gov (United States)

    Fortmeier, Dirk; Mastmeyer, Andre; Schröder, Julian; Handels, Heinz

    2016-01-01

    This study presents a new visuo-haptic virtual reality (VR) training and planning system for percutaneous transhepatic cholangio-drainage (PTCD) based on partially segmented virtual patient models. We only use partially segmented image data instead of a full segmentation and circumvent the necessity of surface or volume mesh models. Haptic interaction with the virtual patient during virtual palpation, ultrasound probing and needle insertion is provided. Furthermore, the VR simulator includes X-ray and ultrasound simulation for image-guided training. The visualization techniques are GPU-accelerated by implementation in Cuda and include real-time volume deformations computed on the grid of the image data. Computation on the image grid enables straightforward integration of the deformed image data into the visualization components. To provide shorter rendering times, the performance of the volume deformation algorithm is improved by a multigrid approach. To evaluate the VR training system, a user evaluation has been performed and deformation algorithms are analyzed in terms of convergence speed with respect to a fully converged solution. The user evaluation shows positive results with increased user confidence after a training session. It is shown that using partially segmented patient data and direct volume rendering is suitable for the simulation of needle insertion procedures such as PTCD.

  7. Repair of Segmental Load-Bearing Bone Defect by Autologous Mesenchymal Stem Cells and Plasma-Derived Fibrin Impregnated Ceramic Block Results in Early Recovery of Limb Function

    Directory of Open Access Journals (Sweden)

    Min Hwei Ng

    2014-01-01

    Full Text Available Calcium phosphate-based bone substitutes have not been used to repair load-bearing bone defects due to their weak mechanical property. In this study, we reevaluated the functional outcomes of combining ceramic block with osteogenic-induced mesenchymal stem cells and platelet-rich plasma (TEB to repair critical-sized segmental tibial defect. Comparisons were made with fresh marrow-impregnated ceramic block (MIC and partially demineralized allogeneic bone block (ALLO. Six New Zealand White female rabbits were used in each study group and three rabbits with no implants were used as negative controls. By Day 90, 4/6 rabbits in TEB group and 2/6 in ALLO and MIC groups resumed normal gait pattern. Union was achieved significantly faster in TEB group with a radiological score of 4.50 ± 0.78 versus ALLO (1.06 ± 0.32, MIC (1.28 ± 0.24, and negative controls (0. Histologically, TEB group scored the highest percentage of new bone (82% ± 5.1% compared to ALLO (5% ± 2.5% and MIC (26% ± 5.2%. Biomechanically, TEB-treated tibiae achieved the highest compressive strength (43.50 ± 12.72 MPa compared to those treated with ALLO (15.15 ± 3.57 MPa and MIC (23.28 ± 6.14 MPa. In conclusion, TEB can repair critical-sized segmental load-bearing bone defects and restore limb function.

  8. H-Seda: Partial Packet Recovery with Heterogeneous Block Sizes for Wireless Sensor Networks

    KAUST Repository

    Meer, Ammar M.

    2012-01-01

    . Maximizing bandwidth utilization while maintaining low frame error rate has been an interesting problem. Frame fragmentation into small blocks with dedicated error detection codes per block can reduce the unnecessary retransmission of the correctly received

  9. Avian skull morphological evolution: exploring exo- and endocranial covariation with two-block partial least squares.

    Science.gov (United States)

    Marugán-Lobón, Jesús; Buscalioni, Angela D

    2006-01-01

    While rostral variation has been the subject of detailed avian evolutionary research, avian skull organization, characterized by a flexed or extended appearance of the skull, has eventually become neglected by mainstream evolutionary inquiries. This study aims to recapture its significance, evaluating possible functional, phylogenetic and developmental factors that may be underlying it. In order to estimate which, and how, elements of the skull intervene in patterning the skull we tested the statistical interplay between a series of old mid-sagittal angular measurements (mostly endocranial) in combination with newly obtained skull metrics based on landmark superimposition methods (exclusively exocranial shape), by means of the statistic-morphometric technique of two-block partial least squares. As classic literature anticipated, we found that the external appearance of the skull corresponds to the way in which the plane of the caudal cranial base is oriented, in connection with the orientations of the plane of the foramen magnum and of the lateral semicircular canal. The pattern of covariation found between metrics conveys flexed or extended appearances of the skull implicitly within a single and statistically significant dimension of covariation. Marked shape changes with which angles covary concentrate at the supraoccipital bone, the cranial base and the antorbital window, whereas the plane measuring the orientation of the anterior portion of the rostrum does not intervene. Statistical covariance between elements of the caudal cranial base and the occiput inplies that morphological integration underlies avian skull macroevolutionary organization as a by-product of the regional concordance of such correlated elements within the early embryonic chordal domain of mesodermic origin.

  10. Lumbar segmental nerve blocks with local anesthetics, pain relief, and motor function: a prospective double-blind study between lidocaine and ropivacaine.

    Science.gov (United States)

    Wolff, André P; Wilder Smith, Oliver H G; Crul, Ben J P; van de Heijden, Marc P; Groen, Gerbrand J

    2004-08-01

    Selective segmental nerve blocks with local anesthetics are applied for diagnostic purposes in patients with chronic back pain to determine the segmental level of the pain. We performed this study to establish myotomal motor effects after L4 spinal nerve blocks by lidocaine and ropivacaine and to evaluate the relationship with pain. Therefore, 20 patients, of which 19 finished the complete protocol, with chronic lumbosacral radicular pain without neurological deficits underwent segmental nerve blocks at L4 with both lidocaine and ropivacaine. Pain intensity scores (verbal numeric rating scale; VNRS) and the maximum voluntary muscle force (MVMF; using a dynamometer expressed in newtons) of the tibialis anterior and quadriceps femoris muscles were measured on the painful side and on the control side. The median VNRS decrease was 4.0 (P segmental nerve (L4) block is associated with increased quadriceps femoris and tibialis anterior MVMF, without differences for lidocaine and ropivacaine.

  11. Markov random field and Gaussian mixture for segmented MRI-based partial volume correction in PET

    International Nuclear Information System (INIS)

    Bousse, Alexandre; Thomas, Benjamin A; Erlandsson, Kjell; Hutton, Brian F; Pedemonte, Stefano; Ourselin, Sébastien; Arridge, Simon

    2012-01-01

    In this paper we propose a segmented magnetic resonance imaging (MRI) prior-based maximum penalized likelihood deconvolution technique for positron emission tomography (PET) images. The model assumes the existence of activity classes that behave like a hidden Markov random field (MRF) driven by the segmented MRI. We utilize a mean field approximation to compute the likelihood of the MRF. We tested our method on both simulated and clinical data (brain PET) and compared our results with PET images corrected with the re-blurred Van Cittert (VC) algorithm, the simplified Guven (SG) algorithm and the region-based voxel-wise (RBV) technique. We demonstrated our algorithm outperforms the VC algorithm and outperforms SG and RBV corrections when the segmented MRI is inconsistent (e.g. mis-segmentation, lesions, etc) with the PET image. (paper)

  12. Construction of carrier state viruses with partial genomes of the segmented dsRNA bacteriophages

    International Nuclear Information System (INIS)

    Sun Yang; Qiao Xueying; Mindich, Leonard

    2004-01-01

    The cystoviridae are bacteriophages with genomes of three segments of dsRNA enclosed within a polyhedral capsid. Two members of this family, PHI6 and PHI8, have been shown to form carrier states in which the virus replicates as a stable episome in the host bacterium while expressing reporter genes such as kanamycin resistance or lacα. The carrier state does not require the activity of all the genes necessary for phage production. It is possible to generate carrier states by infecting cells with virus or by electroporating nonreplicating plasmids containing cDNA copies of the viral genomes into the host cells. We have found that carrier states in both PHI6 and PHI8 can be formed at high frequency with all three genomic segments or with only the large and small segments. The large genomic segment codes for the proteins that constitute the inner core of the virus, which is the structure responsible for the packaging and replication of the genome. In PHI6, a carrier state can be formed with the large and middle segment if mutations occur in the gene for the major structural protein of the inner core. In PHI8, carrier state formation requires the activity of genes 8 and 12 of segment S

  13. Does segmental overlap help or hurt? Evidence from blocked cyclic naming in spoken and written production.

    Science.gov (United States)

    Breining, Bonnie; Nozari, Nazbanou; Rapp, Brenda

    2016-04-01

    Past research has demonstrated interference effects when words are named in the context of multiple items that share a meaning. This interference has been explained within various incremental learning accounts of word production, which propose that each attempt at mapping semantic features to lexical items induces slight but persistent changes that result in cumulative interference. We examined whether similar interference-generating mechanisms operate during the mapping of lexical items to segments by examining the production of words in the context of others that share segments. Previous research has shown that initial-segment overlap amongst a set of target words produces facilitation, not interference. However, this initial-segment facilitation is likely due to strategic preparation, an external factor that may mask underlying interference. In the present study, we applied a novel manipulation in which the segmental overlap across target items was distributed unpredictably across word positions, in order to reduce strategic response preparation. This manipulation led to interference in both spoken (Exp. 1) and written (Exp. 2) production. We suggest that these findings are consistent with a competitive learning mechanism that applies across stages and modalities of word production.

  14. Anatomically guided voxel-based partial volume effect correction in brain PET : Impact of MRI segmentation

    NARCIS (Netherlands)

    Gutierrez, Daniel; Montandon, Marie-Louise; Assal, Frederic; Allaoua, Mohamed; Ratib, Osman; Loevblad, Karl-Olof; Zaidi, Habib

    2012-01-01

    Partial volume effect is still considered one of the main limitations in brain PET imaging given the limited spatial resolution of current generation PET scanners. The accuracy of anatomically guided partial volume effect correction (PVC) algorithms in brain PET is largely dependent on the

  15. A new venous conduit utilizing the recipient portal vein branches for segment V in adult partial liver transplantation.

    Science.gov (United States)

    Moon, I S; Kim, D G; Lee, M D; Hong, S K; Park, S C; Oh, D Y; Ahn, S T; Lee, Y J

    2005-03-01

    Right anterior-medial lobe congestion due to temporary clamping of segment V and/or VIII is common in the operative theater during adult donor right lobe liver transplantation, the most common procedure in our institute. We have used an autogenous saphenous vein conduit to recipient portal vein tributaries in 15 cases, as a "Y-to-I venoplasty" since January 2004. The recipient portal vein is transected 5 mm proximal to its bifurcation and extended to both sides with partial hepatic dissection. The "Y-to-I venoplasty" is made by suture closure of the portal vein transversely to form a tube. The average length is 7.5 cm with a 1.3 cm width. One end of "Y-to-I venoplasty" conduit is anastomosed to the donor segment V branch on the back table. And the other end is anastomosed directly to the IVC via a new window or the middle hepatic vein stump in recipient. The phase distension of the conduit with respiration is noted in the operative field. A 6/15 (40%) patency rate, was observed by CT angiography at the second postoperative week. All-patient conduits showed good flow on serial examinations at the 60th postoperative day. This new venous graft, made of recipient portal vein is a good conduit for segment V decongestion in adult right lobe partial liver transplantation.

  16. Synthesis and Self-Assembly of Block Copolymers Containing Temperature Sensitive and Degradable Chain Segments.

    Science.gov (United States)

    Gong, Hong-Liang; Lei, Lei; Shi, Shu-Xian; Xia, Yu-Zheng; Chen, Xiao-Nong

    2018-05-01

    In this work, polylactide-b-poly(N-isopropylacrylamide) were synthesized by the combination of controlled ring-opening polymerization and reversible addition fragmentation chain transfer polymerization. These block copolymers with molecular weight range from 7,900 to 12,000 g/mol and narrow polydispersity (≤1.19) can self-assemble into micelles (polylactide core, poly(N-isopropylacrylamide) shell) in water at certain temperature range, which have been evidenced by laser particle size analyzer proton nuclear magnetic resonance and transmission electron microscopy. Such micelles exhibit obvious thermo-responsive properties: (1) Poly(N-isopropylacrylamide) blocks collapse on the polylactide core as system temperature increase, leading to reduce of micelle size. (2) Micelles with short poly(N-isopropylacrylamide) blocks tend to aggregate together when temperature increased, which is resulted from the reduction of the system hydrophilicity and the decreased repulsive force between micelles.

  17. Automatic Craniomaxillofacial Landmark Digitization via Segmentation-guided Partially-joint Regression Forest Model and Multi-scale Statistical Features

    Science.gov (United States)

    Zhang, Jun; Gao, Yaozong; Wang, Li; Tang, Zhen; Xia, James J.; Shen, Dinggang

    2016-01-01

    Objective The goal of this paper is to automatically digitize craniomaxillofacial (CMF) landmarks efficiently and accurately from cone-beam computed tomography (CBCT) images, by addressing the challenge caused by large morphological variations across patients and image artifacts of CBCT images. Methods We propose a Segmentation-guided Partially-joint Regression Forest (S-PRF) model to automatically digitize CMF landmarks. In this model, a regression voting strategy is first adopted to localize each landmark by aggregating evidences from context locations, thus potentially relieving the problem caused by image artifacts near the landmark. Second, CBCT image segmentation is utilized to remove uninformative voxels caused by morphological variations across patients. Third, a partially-joint model is further proposed to separately localize landmarks based on the coherence of landmark positions to improve the digitization reliability. In addition, we propose a fast vector quantization (VQ) method to extract high-level multi-scale statistical features to describe a voxel's appearance, which has low dimensionality, high efficiency, and is also invariant to the local inhomogeneity caused by artifacts. Results Mean digitization errors for 15 landmarks, in comparison to the ground truth, are all less than 2mm. Conclusion Our model has addressed challenges of both inter-patient morphological variations and imaging artifacts. Experiments on a CBCT dataset show that our approach achieves clinically acceptable accuracy for landmark digitalization. Significance Our automatic landmark digitization method can be used clinically to reduce the labor cost and also improve digitalization consistency. PMID:26625402

  18. A Simple Differential Modulation Scheme for Quasi-Orthogonal Space-Time Block Codes with Partial Transmit Diversity

    Directory of Open Access Journals (Sweden)

    Lingyang Song

    2007-04-01

    Full Text Available We report a simple differential modulation scheme for quasi-orthogonal space-time block codes. A new class of quasi-orthogonal coding structures that can provide partial transmit diversity is presented for various numbers of transmit antennas. Differential encoding and decoding can be simplified for differential Alamouti-like codes by grouping the signals in the transmitted matrix and decoupling the detection of data symbols, respectively. The new scheme can achieve constant amplitude of transmitted signals, and avoid signal constellation expansion; in addition it has a linear signal detector with very low complexity. Simulation results show that these partial-diversity codes can provide very useful results at low SNR for current communication systems. Extension to more than four transmit antennas is also considered.

  19. Ab interno management of blocked Ahmed valve in the posterior segment.

    Science.gov (United States)

    Odrich, Steven; Wald, Kenneth; Sperber, Laurence

    2013-01-01

    To report a case of late failure of a posterior segment placed Ahmed valve in a uveitic eye with a corneal graft and a minimally invasive, ab interno approach in restoring valve function, pressure control, and preservation of vision. Case report. A 25 gauge trans-conjunctival 3-port pars plana vitrectomy was performed to inspect and clean the ostium of the Ahmed valve of any vitreous debris. The Ahmed valve was not disturbed externally and conjunctival dissection was not performed. A 27-gauge blunt cannula was introduced through the vitrector site and used to cannulate the tube and flush it with balanced salt solution. A bleb was immediately re-established and all instruments were removed requiring no sutures. Intraocular pressure returned to target levels and a filtration bleb was re-established. Corneal graft clarity was restored with resolution of preoperative microcystic edema. Postoperative inflammation was minimal and vision was restored. A nonfunctioning tube shunt residing in the vitreous cavity may be revised ab interno without disturbing the shunt placement or the conjunctiva under which it resides to re-establish filtration.

  20. Analysis of Hansen's Inferior and Superior Partial Anomalies and the Division of the Elliptic Orbit into Two Segments

    Science.gov (United States)

    Sharaf, M. A.; Saad, A. S.

    2017-10-01

    In this paper, a novel analysis was established to prove how Hansen's inferior and superior partial anomalies k and k_1 can divide the elliptic orbit into two segments. The analysis depends on the departures of r (for k) and 1/r (for k1) from their minima. By these departures, we can find: (i) Transformations relating the eccentric anomaly to k and the true anomaly to k1. (ii) Expressions for k and k_1 in terms of the orbital elements. (iii) The interpretation and the intervals of definition of two moduli (X, S) related to k and k_1. (iv) The extreme values of r and the elliptic equations in terms of k and k1. (v) For r' and r'', the modulus X as a measure of the asymmetry of r' (or r'') from r'' (or r'), and the modulus S12 as a measure of the asymmetry of r' and r'' from the minimum value of r. (vi) A description of the segments represented by k and k1. (vii) The relative position of the radius vector at k0° and k1=180°.

  1. Comparison of anterior segment measurements using rotating Scheimpflug imaging and partial coherence interferometry

    Directory of Open Access Journals (Sweden)

    Akbar Fotouhi

    2013-08-01

    Full Text Available METHODS:As part of the first phase of Shahroud Eye Cohort Study with 5 190 subjects of 40 to 64 years of age, CCT and ACD were measured using Scheimpflug imaging with the Pentacam (Oculus, Inc., Lynnwood, WA, USA and partial coherence interferometry with the Allegro BioGraph (Wavelight, Erlangen, Germany.RESULTS:After applying exclusion criteria, we had data of 4 387 subjects with a mean age of 50.7±6.2 years. Mean CCT with Pentacam and BioGraph were 528.6±33.2μm and 525.6±32μm respectively; the difference was statistically significant (PPCONCLUSION:For both CCT and ACD, the BioGraph gave significantly lower values than the Pentacam (P<0.05. Despite the high inter-device correlation, the 95% limits of agreements were wide, and this may limit their interchangeability in measuring the CCT and ACD.

  2. Comparing blends and blocks: Synthesis of partially fluorinated diblock polythiophene copolymers to investigate the thermal stability of optical and morphological properties

    Directory of Open Access Journals (Sweden)

    Pierre Boufflet

    2016-10-01

    Full Text Available The microstructure of the active blend layer has been shown to be a critically important factor in the performance of organic solar devices. Block copolymers provide a potentially interesting avenue for controlling this active layer microstructure in solar cell blends. Here we explore the impact of backbone fluorination in block copolymers of poly(3-octyl-4-fluorothiophenes and poly(3-octylthiophene (F-P3OT-b-P3OT. Two block co-polymers with varying block lengths were prepared via sequential monomer addition under Kumada catalyst transfer polymerisation (KCTP conditions. We compare the behavior of the block copolymer to that of the corresponding homopolymer blends. In both types of system, we find the fluorinated segments tend to dominate the UV–visible absorption and molecular vibrational spectral features, as well as the thermal behavior. In the block copolymer case, non-fluorinated segments appear to slightly frustrate the aggregation of the more fluorinated block. However, in situ temperature dependent Raman spectroscopy shows that the intramolecular order is more thermally stable in the block copolymer than in the corresponding blend, suggesting that such materials may be interesting for enhanced thermal stability of organic photovoltaic active layers based on similar systems.

  3. Manipulation of partially oriented hydroxyapatite building blocks to form flowerlike bundles without acid-base regulation.

    Science.gov (United States)

    Wen, Zhenliang; Wang, Zihao; Chen, Jingdi; Zhong, Shengnan; Hu, Yimin; Wang, Jianhua; Zhang, Qiqing

    2016-06-01

    The application of hydroxyapatite (HAP) in different fields depends greatly on its morphology, composition and structure. Besides, the main inorganic building blocks of human bones and teeth are also HAP. Therefore, accurate shape and aggregation control and of hydroxyapatite particles will be of great interest. Herein, oriented bundles of flowerlike HAP nanorods were successfully prepared through hydrothermal treatment without acid-base regulation, with the mono-alkyl phosphate (MAP) and sodium citrate as surfactant and chelating agent, respectively. The prepared samples were characterized by the X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and zeta potential, the pH value and conductivity value of suspension were characterized by pH meter and conductivity measurement. The results showed that the MAP and citrate play an important role in assembly of HAP nanorods without acid-base regulation. Citrate calcium complex could decompose slowly and release citrate ions at hydrothermal conditions. Besides, the further decomposition of citrate ions could release aconitic acid as the reaction time prolongs. Moreover, the possible scheme for the formation process was discussed in detail. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. A novel exploratory chemometric approach to environmental monitorring by combining block clustering with Partial Least Square (PLS) analysis

    Science.gov (United States)

    2013-01-01

    Background Given the serious threats posed to terrestrial ecosystems by industrial contamination, environmental monitoring is a standard procedure used for assessing the current status of an environment or trends in environmental parameters. Measurement of metal concentrations at different trophic levels followed by their statistical analysis using exploratory multivariate methods can provide meaningful information on the status of environmental quality. In this context, the present paper proposes a novel chemometric approach to standard statistical methods by combining the Block clustering with Partial least square (PLS) analysis to investigate the accumulation patterns of metals in anthropized terrestrial ecosystems. The present study focused on copper, zinc, manganese, iron, cobalt, cadmium, nickel, and lead transfer along a soil-plant-snai food chain, and the hepatopancreas of the Roman snail (Helix pomatia) was used as a biological end-point of metal accumulation. Results Block clustering deliniates between the areas exposed to industrial and vehicular contamination. The toxic metals have similar distributions in the nettle leaves and snail hepatopancreas. PLS analysis showed that (1) zinc and copper concentrations at the lower trophic levels are the most important latent factors that contribute to metal accumulation in land snails; (2) cadmium and lead are the main determinants of pollution pattern in areas exposed to industrial contamination; (3) at the sites located near roads lead is the most threatfull metal for terrestrial ecosystems. Conclusion There were three major benefits by applying block clustering with PLS for processing the obtained data: firstly, it helped in grouping sites depending on the type of contamination. Secondly, it was valuable for identifying the latent factors that contribute the most to metal accumulation in land snails. Finally, it optimized the number and type of data that are best for monitoring the status of metallic

  5. A novel exploratory chemometric approach to environmental monitorring by combining block clustering with Partial Least Square (PLS) analysis.

    Science.gov (United States)

    Nica, Dragos V; Bordean, Despina Maria; Pet, Ioan; Pet, Elena; Alda, Simion; Gergen, Iosif

    2013-08-30

    Given the serious threats posed to terrestrial ecosystems by industrial contamination, environmental monitoring is a standard procedure used for assessing the current status of an environment or trends in environmental parameters. Measurement of metal concentrations at different trophic levels followed by their statistical analysis using exploratory multivariate methods can provide meaningful information on the status of environmental quality. In this context, the present paper proposes a novel chemometric approach to standard statistical methods by combining the Block clustering with Partial least square (PLS) analysis to investigate the accumulation patterns of metals in anthropized terrestrial ecosystems. The present study focused on copper, zinc, manganese, iron, cobalt, cadmium, nickel, and lead transfer along a soil-plant-snai food chain, and the hepatopancreas of the Roman snail (Helix pomatia) was used as a biological end-point of metal accumulation. Block clustering deliniates between the areas exposed to industrial and vehicular contamination. The toxic metals have similar distributions in the nettle leaves and snail hepatopancreas. PLS analysis showed that (1) zinc and copper concentrations at the lower trophic levels are the most important latent factors that contribute to metal accumulation in land snails; (2) cadmium and lead are the main determinants of pollution pattern in areas exposed to industrial contamination; (3) at the sites located near roads lead is the most threatfull metal for terrestrial ecosystems. There were three major benefits by applying block clustering with PLS for processing the obtained data: firstly, it helped in grouping sites depending on the type of contamination. Secondly, it was valuable for identifying the latent factors that contribute the most to metal accumulation in land snails. Finally, it optimized the number and type of data that are best for monitoring the status of metallic contamination in terrestrial ecosystems

  6. Soliton wave model for simulating the slug formation in vertical-to-horizontal partially blocked pipes

    International Nuclear Information System (INIS)

    Nihan Onder; Alberto Teyssedou; Danila Roubtsov

    2005-01-01

    Full text of publication follows: In CANDU reactors the fuel channels are connected to inlet and outlet headers by feeder-pipes that consist of vertical and horizontal legs. In some feeders, orifices are installed for flow adjustment. During a postulated Loss of Coolant Accidents, the emergency cooling water injected into the inlet and outlet headers enters the fuel channels through the feeder pipes. Steam produced in the feeders and in the fuel channels may flow in the direction opposite to that of the water, thereby creating vertical to horizontal Counter-Current Flow (CCF). The rate at which the cooling water enters the fuel channel may be substantially limited by the flooding phenomena that entrains the water in the same direction as the steam flow. Steam flowing in the direction opposite to the cooling water can bring about the formation of slug flow. Long slugs of liquid moving at relatively high speed are transported back towards the headers by the steam. This phenomenon substantially reduces the amount of cooling water that can reach the reactor core. We conducted CCF experiments using a vertical-to-horizontal test section connected by 90 deg. elbows, with an orifice installed in the horizontal leg. Four different orifices were used to carry out the experiments. We have observed that soliton-type waves generated close to the elbow propagate in the horizontal leg towards the orifice, where a partial reflection takes place. Without an orifice, the soliton waves are reflected from the second elbow. The reflected waves move in the opposite direction to that of the incident wave. Since soliton-type waves are periodically generated, the incident and reflected waves interfere at some place in the horizontal leg. If the amplitude of the interference wave is high enough, the bridging of the tubes occur, which generates the slugs. During the experiments the water and air flow rates, pressures and void fraction distributions were measured. The slug propagation

  7. Structural Behavior of a Long-Span Partially Earth-Anchored Cable-Stayed Bridge during Installation of a Key Segment by Thermal Prestressing

    Directory of Open Access Journals (Sweden)

    Sang-Hyo Kim

    2016-08-01

    Full Text Available This study investigated structural behavior of long-span partially earth-anchored cable-stayed bridges with a main span length of 810 m that use a new key segment closing method based on a thermal prestressing technique. A detailed construction sequence analysis matched with the free cantilever method (FCM was performed using a three-dimensional finite element (FE model of a partially earth-anchored cable-stayed bridge. The new method offers an effective way of connecting key segments by avoiding large movements resulting from the removal of the longitudinal restraint owing to the asymmetry of axial forces in the girders near the pylons. The new method develops new member forces through the process of heating the cantilever system before installing the key segment and cooling the system continuously after installing key segments. The resulting forces developed by the thermal process enhance the structural behavior of partially earth-anchored cable-stayed bridges owing to decreased axial forces in the girders.

  8. Brain extraction in partial volumes T2*@7T by using a quasi-anatomic segmentation with bias field correction.

    Science.gov (United States)

    Valente, João; Vieira, Pedro M; Couto, Carlos; Lima, Carlos S

    2018-02-01

    Poor brain extraction in Magnetic Resonance Imaging (MRI) has negative consequences in several types of brain post-extraction such as tissue segmentation and related statistical measures or pattern recognition algorithms. Current state of the art algorithms for brain extraction work on weighted T1 and T2, being not adequate for non-whole brain images such as the case of T2*FLASH@7T partial volumes. This paper proposes two new methods that work directly in T2*FLASH@7T partial volumes. The first is an improvement of the semi-automatic threshold-with-morphology approach adapted to incomplete volumes. The second method uses an improved version of a current implementation of the fuzzy c-means algorithm with bias correction for brain segmentation. Under high inhomogeneity conditions the performance of the first method degrades, requiring user intervention which is unacceptable. The second method performed well for all volumes, being entirely automatic. State of the art algorithms for brain extraction are mainly semi-automatic, requiring a correct initialization by the user and knowledge of the software. These methods can't deal with partial volumes and/or need information from atlas which is not available in T2*FLASH@7T. Also, combined volumes suffer from manipulations such as re-sampling which deteriorates significantly voxel intensity structures making segmentation tasks difficult. The proposed method can overcome all these difficulties, reaching good results for brain extraction using only T2*FLASH@7T volumes. The development of this work will lead to an improvement of automatic brain lesions segmentation in T2*FLASH@7T volumes, becoming more important when lesions such as cortical Multiple-Sclerosis need to be detected. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Application and analysis of retroperitoneal laparoscopic partial nephrectomy with sequential segmental renal artery clamping for patients with multiple renal tumor: initial experience.

    Science.gov (United States)

    Zhu, Jundong; Jiang, Fan; Li, Pu; Shao, Pengfei; Liang, Chao; Xu, Aiming; Miao, Chenkui; Qin, Chao; Wang, Zengjun; Yin, Changjun

    2017-09-11

    To explore the feasibility and safety of retroperitoneal laparoscopic partial nephrectomy with sequential segmental renal artery clamping for the patients with multiple renal tumor of who have solitary kidney or contralateral kidney insufficiency. Nine patients who have undergone retroperitoneal laparoscopic partial nephrectomy with sequential segmental renal artery clamping between October 2010 and January 2017 were retrospectively analyzed. Clinical materials and parameters during and after the operation were summarized. Nineteen tumors were resected in nine patients and the operations were all successful. The operation time ranged from 100 to 180 min (125 min); clamping time of segmental renal artery was 10 ~ 30 min (23 min); the amount of blood loss during the operation was 120 ~ 330 ml (190 ml); hospital stay after the operation is 3 ~ 6d (5d). There was no complication during the perioperative period, and the pathology diagnosis after the surgery showed that there were 13 renal clear cell carcinomas, two papillary carcinoma and four perivascular epithelioid cell tumors with negative margins from the 19 tumors. All patients were followed up for 3 ~ 60 months, and no local recurrence or metastasis was detected. At 3-month post-operation follow-up, the mean serum creatinine was 148.6 ± 28.1 μmol/L (p = 0.107), an increase of 3.0 μmol/L from preoperative baseline. For the patients with multiple renal tumors and solitary kidney or contralateral kidney insufficiency, retroperitoneal laparoscopic partial nephrectomy with sequential segmental renal artery clamping was feasible and safe, which minimized the warm ischemia injury to the kidney and preserved the renal function effectively.

  10. Intrinsic spatial resolution evaluation of the X'tal cube PET detector based on a 3D crystal block segmented by laser processing.

    Science.gov (United States)

    Yoshida, Eiji; Tashima, Hideaki; Inadama, Naoko; Nishikido, Fumihiko; Moriya, Takahiro; Omura, Tomohide; Watanabe, Mitsuo; Murayama, Hideo; Yamaya, Taiga

    2013-01-01

    The X'tal cube is a depth-of-interaction (DOI)-PET detector which is aimed at obtaining isotropic resolution by effective readout of scintillation photons from the six sides of a crystal block. The X'tal cube is composed of the 3D crystal block with isotropic resolution and arrays of multi-pixel photon counters (MPPCs). In this study, to fabricate the 3D crystal block efficiently and precisely, we applied a sub-surface laser engraving (SSLE) technique to a monolithic crystal block instead of gluing segmented small crystals. The SSLE technique provided micro-crack walls which carve a groove into a monolithic scintillator block. Using the fabricated X'tal cube, we evaluated its intrinsic spatial resolution to show a proof of concept of isotropic resolution. The 3D grids of 2 mm pitch were fabricated into an 18 × 18 × 18 mm(3) monolithic lutetium yttrium orthosilicate (LYSO) crystal by the SSLE technique. 4 × 4 MPPCs were optically coupled to each surface of the crystal block. The X'tal cube was uniformly irradiated by (22)Na gamma rays, and all of the 3D grids on the 3D position histogram were separated clearly by an Anger-type calculation from the 96-channel MPPC signals. Response functions of the X'tal cube were measured by scanning with a (22)Na point source. The gamma-ray beam with a 1.0 mm slit was scanned in 0.25 mm steps by positioning of the X'tal cube at vertical and 45° incident angles. The average FWHM resolution at both incident angles was 2.1 mm. Therefore, we confirmed the isotropic spatial resolution performance of the X'tal cube.

  11. Role of ultrasound guided transversus abdominis plane block as a component of multimodal analgesic regimen for lower segment caesarean section: a randomized double blind clinical study.

    Science.gov (United States)

    Jadon, Ashok; Jain, Priyanka; Chakraborty, Swastika; Motaka, Mayur; Parida, Sudhansu Sekhar; Sinha, Neelam; Agrawal, Amit; Pati, Asit Kumar

    2018-05-14

    While opioids are the mainstay for post-operative analgesia after lower segment caesarean section, they are associated with various untoward effects. Ultrasound guided transversus abdominis plane (TAP) block has been postulated to provide effective analgesia for caesarean section. We evaluated the analgesic efficacy of this block for post caesarean analgesia in a randomised controlled trial. One hundred thirty-nine mothers undergoing caesarean delivery were randomised to receive TAP block with either 20 ml 0.375% ropivacaine or 20 ml saline after obtaining informed consent. All the subjects received a standard spinal anaesthetic and diclofenac was administered for post-operative pain. Breakthrough pain was treated with tramadol. Post-operatively, all the subjects were assessed at 0, 2, 4, 6, 8, 10, 12, 18 & 24 h. The primary outcome was the time to first analgesic request. The secondary measures of outcome were pain, nausea, sedation, number of doses of tramadol administered and satisfaction with the pain management. The median (interquartile range) time to first analgesic request was prolonged in the TAP group compared to the control group (p consumption when used for multimodal analgesia for pain relief after caesarean section. However, the risk of local anaesthetic systemic toxicity remains unknown with this block. Hence larger safety trials and measures to limit this complication need to be ascertained. The trial was registered with the Clinical Trial Registry of India ( CTRI/2017/03/008194 ) on 23/03/2017 (trial registered retrospectively).

  12. Analysis of the coding potential of the partially overlapping 3' ORF in segment 5 of the plant fijiviruses

    Directory of Open Access Journals (Sweden)

    Atkins John F

    2009-03-01

    Full Text Available Abstract The plant-infecting members of the genus Fijivirus (family Reoviridae have linear dsRNA genomes divided into 10 segments, two of which contain two substantial and non-overlapping ORFs, while the remaining eight are apparently monocistronic. However, one of these – namely segment 5 – contains a second long ORF (~200+ codons that overlaps the 3' end of the major ORF (~920–940 codons in the +1 reading frame. In this report, we use bioinformatic techniques to analyze the pattern of base variations across an alignment of fijivirus segment 5 sequences, and show that this 3' ORF has a strong coding signature. Possible translation mechanisms for this unusually positioned ORF are discussed.

  13. Synthesis of DNA block copolymers with extended nucleic acid segments by enzymatic ligation : cut and paste large hybrid architectures

    NARCIS (Netherlands)

    Ayaz, Meryem S.; Kwak, Minseok; Alemdaroglu, Fikri E.; Wang, Jie; Berger, Ruediger; Herrmann, Andreas; Berger, Rüdiger

    2011-01-01

    Ultra-high molecular weight DNA/polymer hybrid materials were prepared employing molecular biology techniques. Nucleic acid restriction and ligation enzymes were used to generate linear DNA di- and triblock copolymers that contain up to thousands of base pairs in the DNA segments.

  14. Neogene tectonic block rotations and margin curvature at the Pampean flat slab segment (28º-33º SL, Argentina

    Directory of Open Access Journals (Sweden)

    M.S Japas

    2012-06-01

    Full Text Available Available paleomagnetic data from the Pampean flat slab segment reveal a heterogeneous rotation pattern that is interpreted herein as the result of the overprinting of late NNW-WNW left-lateral brittle-ductile megashear zones that would be also responsible for the continental margin bending.La base de datos paleomagnéticos disponible para el segmento de losa plana Pampeano revela un patrón de rotaciones heterogéneo como resultado de la sobreimposición de zonas de cizalla frágil-dúctiles regionales, de desplazamiento lateral izquierdo y rumbo NNO a ONO, las que habrían producido además la curvatura del margen continental.

  15. Partial volume correction and image segmentation for accurate measurement of standardized uptake value of grey matter in the brain.

    Science.gov (United States)

    Bural, Gonca; Torigian, Drew; Basu, Sandip; Houseni, Mohamed; Zhuge, Ying; Rubello, Domenico; Udupa, Jayaram; Alavi, Abass

    2015-12-01

    Our aim was to explore a novel quantitative method [based upon an MRI-based image segmentation that allows actual calculation of grey matter, white matter and cerebrospinal fluid (CSF) volumes] for overcoming the difficulties associated with conventional techniques for measuring actual metabolic activity of the grey matter. We included four patients with normal brain MRI and fluorine-18 fluorodeoxyglucose (F-FDG)-PET scans (two women and two men; mean age 46±14 years) in this analysis. The time interval between the two scans was 0-180 days. We calculated the volumes of grey matter, white matter and CSF by using a novel segmentation technique applied to the MRI images. We measured the mean standardized uptake value (SUV) representing the whole metabolic activity of the brain from the F-FDG-PET images. We also calculated the white matter SUV from the upper transaxial slices (centrum semiovale) of the F-FDG-PET images. The whole brain volume was calculated by summing up the volumes of the white matter, grey matter and CSF. The global cerebral metabolic activity was calculated by multiplying the mean SUV with total brain volume. The whole brain white matter metabolic activity was calculated by multiplying the mean SUV for the white matter by the white matter volume. The global cerebral metabolic activity only reflects those of the grey matter and the white matter, whereas that of the CSF is zero. We subtracted the global white matter metabolic activity from that of the whole brain, resulting in the global grey matter metabolism alone. We then divided the grey matter global metabolic activity by grey matter volume to accurately calculate the SUV for the grey matter alone. The brain volumes ranged between 1546 and 1924 ml. The mean SUV for total brain was 4.8-7. Total metabolic burden of the brain ranged from 5565 to 9617. The mean SUV for white matter was 2.8-4.1. On the basis of these measurements we generated the grey matter SUV, which ranged from 8.1 to 11.3. The

  16. Phylogenetic analysis of partial RNA-polymerase blocks II and III of Rabies virus isolated from the main rabies reservoirs in Brazil.

    Science.gov (United States)

    Carnieli, Pedro; de Novaes Oliveira, Rafael; de Oliveira Fahl, Willian; de Carvalho Ruthner Batista, Helena Beatriz; Scheffer, Karin Corrêa; Iamamoto, Keila; Castilho, Juliana Galera

    2012-08-01

    This study describes the results of the sequencing and analysis of segments of Blocks II and III of the RNA polymerase L gene of Rabies virus isolates from different reservoir species of Brazil. The phylogenetic relations of the virus were determined and a variety of species-specific nucleotides were found in the analyzed areas, but the majority of these mutations were found to be synonymous. However, an analysis of the putative amino acid sequences were shown to have some characteristic mutations between some reservoir species of Brazil, indicating that there was positive selection in the RNA polymerase L gene of Rabies virus. On comparing the putative viral sequences obtained from the Brazilian isolates and other Lyssavirus, it was determined that amino acid mutations occurred in low-restriction areas. This study of the L gene of Rabies virus is the first to be conducted with samples of virus isolates from Brazil, and the results obtained will help in the determination of the phylogenetic relations of the virus.

  17. Quantitative Analysis of Adulterations in Oat Flour by FT-NIR Spectroscopy, Incomplete Unbalanced Randomized Block Design, and Partial Least Squares

    Directory of Open Access Journals (Sweden)

    Ning Wang

    2014-01-01

    Full Text Available This paper developed a rapid and nondestructive method for quantitative analysis of a cheaper adulterant (wheat flour in oat flour by NIR spectroscopy and chemometrics. Reflectance FT-NIR spectra in the range of 4000 to 12000 cm−1 of 300 oat flour objects adulterated with wheat flour were measured. The doping levels of wheat flour ranged from 5% to 50% (w/w. To ensure the generalization performance of the method, both the oat and the wheat flour samples were collected from different producing areas and an incomplete unbalanced randomized block (IURB design was performed to include the significant variations that may be encountered in future samples. Partial least squares regression (PLSR was used to develop calibration models for predicting the levels of wheat flour. Different preprocessing methods including smoothing, taking second-order derivative (D2, and standard normal variate (SNV transformation were investigated to improve the model accuracy of PLS. The root mean squared error of Monte Carlo cross-validation (RMSEMCCV and root mean squared error of prediction (RMSEP were 1.921 and 1.975 (%, w/w by D2-PLS, respectively. The results indicate that NIR and chemometrics can provide a rapid method for quantitative analysis of wheat flour in oat flour.

  18. Self-assembly of graft polyurethanes having both crystallizable poly({epsilon}-caprolactone) blocks and soft poly(n-butyl acrylate) segments

    Energy Technology Data Exchange (ETDEWEB)

    Ibarboure, E.; Baron, A.; Papon, E. [Laboratoire de Chimie des Polymeres Organiques (LCPO), CNRS, Universite Bordeaux I. 16, Avenue Pey Berland, 33607, Pessac-Cedex (France); Rodriguez-Hernandez, J., E-mail: jrodriguez@enscpb.f [Laboratoire de Chimie des Polymeres Organiques (LCPO), CNRS, Universite Bordeaux I. 16, Avenue Pey Berland, 33607, Pessac-Cedex (France)

    2009-04-02

    We report the self-assembly behavior of graft polyurethanes combining in its structure soft lateral poly(n-butyl acrylate) (PnBuA) chains with rigid and crystallizable polycaprolactone (PCL) segments. Segmented polyurethanes microphase separated into high-glass transition temperature PCL hard and low-glass transition temperature PnBuA soft domains. The variation of the microstructure as a function of the hard segment content (ratio hard to soft segments) within the structure has been studied by using atomic force microscopy. Additionally, the crystallization mechanism appeared to be directly related to the properties of the substrates forming parallel lamellar structures on hydrophilic substrates and perpendicular lamellae with hydrophobic substrates.

  19. Poly(ethylene oxide)/poly(butylene terephthalate) segmented block copolymers: the effect of copolymer composition on physical properties and degradation behavior

    NARCIS (Netherlands)

    Deschamps, A.A.; Grijpma, Dirk W.; Feijen, Jan

    2001-01-01

    In this study, the influence of copolymer composition on the physical properties and the degradation behavior of thermoplastic elastomers based on poly(ethylene oxide) (PEO) and poly(butylene terephthalate) (PBT) segments is investigated. These materials are intended to be used in medical

  20. Operating characteristics of a partial-block randomized crossover bioequivalence study for dutasteride, a drug with a long half-life: investigation through simulation and comparison with final results.

    Science.gov (United States)

    Cai, Gengqian; Thiessen, Jake J; Baidoo, Charlotte A; Fossler, Michael J

    2010-10-01

    Studies to establish bioequivalence (BE) of a drug are important elements in support of drug applications. A typical BE study is conducted as a single dose, randomized, 2-period crossover design. For drugs with long half lives (≥ 48 hours) and evaluation of multiple BE objectives in 1 trial, this design may not be adequate. A parallel design may then be a more appropriate choice. However, parallel designs require increased sample size, which can become substantial. One option that is a compromise between the complete randomized block design and the parallel design is a partial-block crossover design. This approach came about during the development of a combination of dutasteride and tamsulosin. Previous experience with performing single-dose dutasteride studies suggested that 28 days of washout is needed between treatments because of its half-life of 7-9 days. Simulations were performed to assess the operating characteristics of this design using a previously developed PK model. Four scenarios were developed, and each scenario was simulated 500 times. The results showed that this design demonstrated acceptable consumer and producer risk. Partial-block crossover designs should be considered for studies when the half-life of the drug is long and there are more than 2 periods.

  1. Coronal View Ultrasound Imaging of Movement in Different Segments of the Tongue during Paced Recital: Findings from Four Normal Speakers and a Speaker with Partial Glossectomy

    Science.gov (United States)

    Bressmann, Tim; Flowers, Heather; Wong, Willy; Irish, Jonathan C.

    2010-01-01

    The goal of this study was to quantitatively describe aspects of coronal tongue movement in different anatomical regions of the tongue. Four normal speakers and a speaker with partial glossectomy read four repetitions of a metronome-paced poem. Their tongue movement was recorded in four coronal planes using two-dimensional B-mode ultrasound…

  2. Nerve Blocks

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Nerve Blocks A nerve block is an injection to ... the limitations of Nerve Block? What is a Nerve Block? A nerve block is an anesthetic and/ ...

  3. Status of the segment interconnect, cable segment ancillary logic, and the cable segment hybrid driver projects

    International Nuclear Information System (INIS)

    Swoboda, C.; Barsotti, E.; Chappa, S.; Downing, R.; Goeransson, G.; Lensy, D.; Moore, G.; Rotolo, C.; Urish, J.

    1985-01-01

    The FASTBUS Segment Interconnect (SI) provides a communication path between two otherwise independent, asynchronous bus segments. In particular, the Segment Interconnect links a backplane crate segment to a cable segment. All standard FASTBUS address and data transactions can be passed through the SI or any number of SIs and segments in a path. Thus systems of arbitrary connection complexity can be formed, allowing simultaneous independent processing, yet still permitting devices associated with one segment to be accessed from others. The model S1 Segment Interconnect and the Cable Segment Ancillary Logic covered in this report comply with all the mandatory features stated in the FASTBUS specification document DOE/ER-0189. A block diagram of the SI is shown

  4. Segmentation of complex document

    Directory of Open Access Journals (Sweden)

    Souad Oudjemia

    2014-06-01

    Full Text Available In this paper we present a method for segmentation of documents image with complex structure. This technique based on GLCM (Grey Level Co-occurrence Matrix used to segment this type of document in three regions namely, 'graphics', 'background' and 'text'. Very briefly, this method is to divide the document image, in block size chosen after a series of tests and then applying the co-occurrence matrix to each block in order to extract five textural parameters which are energy, entropy, the sum entropy, difference entropy and standard deviation. These parameters are then used to classify the image into three regions using the k-means algorithm; the last step of segmentation is obtained by grouping connected pixels. Two performance measurements are performed for both graphics and text zones; we have obtained a classification rate of 98.3% and a Misclassification rate of 1.79%.

  5. Effect of a blockage length on the coolability during reflood in a 2 × 2 rod bundle with a 90% partially blocked region

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kihwan, E-mail: kihwankim@kaeri.re.kr [Korea Atomic Energy Research Institute, Daeduk-daero 989-111, Yuseong-Gu, Daejeon 34057 (Korea, Republic of); Kim, Byung-Jae, E-mail: byoungjae@kaeri.re.kr [School of Mechanical Engineering, Chungnam National University, 99 Daehak-ro, Yuseoung-Gu, Daejeon 34134 (Korea, Republic of); Choi, Hae-Seob, E-mail: hschoi@kaeri.re.kr [Korea Atomic Energy Research Institute, Daeduk-daero 989-111, Yuseong-Gu, Daejeon 34057 (Korea, Republic of); Moon, Sang-Ki, E-mail: skmoon@kaeri.re.kr [Korea Atomic Energy Research Institute, Daeduk-daero 989-111, Yuseong-Gu, Daejeon 34057 (Korea, Republic of); Song, Chul-Hwa, E-mail: chsong@kaeri.re.kr [Korea Atomic Energy Research Institute, Daeduk-daero 989-111, Yuseong-Gu, Daejeon 34057 (Korea, Republic of)

    2017-02-15

    Highlights: • This test was conducted to understand the effect of blockage length on the coolability. • Reflood tests were conducted with blockage simulators for various reflood rates. • The coolability in the downstream of the blockage region is significantly enhanced. - Abstract: If fuel rods are ballooned or rearranged during the reflood phase of a large break loss-of-coolant accident (LBLOCA) in a pressurized-water reactor (PWR), the transient heat transfer behavior is entirely different with those of the intact fuel rods owing to the deformed blockage region. The coolability in the blocked region depends on a complex two-phase heat transfer with various thermal hydraulic conditions. In addition, the blockage characteristics, such as the blockage ratio, length, shape, and configurations, are also significant factors affecting the coolability. In the present study, reflood experiments were carried out to understand the effect of the blockage length upon the coolability by varying the reflooding rates. The experiments were performed in electrically heated 2 × 2 rod bundles with blockage simulators having the same blockage ratio but different blockage lengths. The characteristics of quenching and heat transfer were evaluated to investigate the influence of the blockage region on the coolability. The droplet behaviors were also observed by measuring the droplets velocity and size near the blockage region. The coolability in the downstream region of the blockage was significantly enhanced, owing to the reduced flow area of the sub-channel, intensification of turbulence, and the entrained droplets in the blockage region.

  6. Partial Least Squares with Structured Output for Modelling the Metabolomics Data Obtained from Complex Experimental Designs: A Study into the Y-Block Coding

    Directory of Open Access Journals (Sweden)

    Yun Xu

    2016-10-01

    Full Text Available Partial least squares (PLS is one of the most commonly used supervised modelling approaches for analysing multivariate metabolomics data. PLS is typically employed as either a regression model (PLS-R or a classification model (PLS-DA. However, in metabolomics studies it is common to investigate multiple, potentially interacting, factors simultaneously following a specific experimental design. Such data often cannot be considered as a “pure” regression or a classification problem. Nevertheless, these data have often still been treated as a regression or classification problem and this could lead to ambiguous results. In this study, we investigated the feasibility of designing a hybrid target matrix Y that better reflects the experimental design than simple regression or binary class membership coding commonly used in PLS modelling. The new design of Y coding was based on the same principle used by structural modelling in machine learning techniques. Two real metabolomics datasets were used as examples to illustrate how the new Y coding can improve the interpretability of the PLS model compared to classic regression/classification coding.

  7. Neutral complexes as oxidants for the reduced form of parsley (Petroselinum crispum) [2Fe--2S] ferredoxin. Evidence for partial blocking by redox-inactive Cr(III) complexes.

    Science.gov (United States)

    Adzamli, I K; Kim, H O; Sykes, A G

    1982-01-01

    The 1 : 1 reactions of three neutral Co(III) oxidants, Co(acac)3, Co(NH3)3(NO2)3 and Co(acac)2(NH3)(NO2), with reduced parsley (Petroselinum crispum) [2Fe--2S] ferredoxin (which carries a substantial negative charge), have been studied at 25 degrees C, pH 8.0 (Tris/HCl), I0.10 (NaCl). Whereas it has previously been demonstrated that with Co(NH3)6+ as oxidant the reaction if completely blocked by redox-inactive Cr(NH3)63+, the neutral oxidants are only partially blocked by this same complex. The effects of three Cr(III) complexes, Cr(NH3)63+%, Cr(en)33+ and (en)2Cr . mu(OH,O2CCH3) . CR(en)24+ have been investigated. Kinetic data for the response of 3+, neutral, as well as 1--oxidants to the presence of 3+ (and 4+) Cr(III) complexes can now be rationalized in terms of a single functional site on the protein for electron transfer. Electrostatics have a significant influence on association at this site. PMID:7115307

  8. Polyether based segmented copolymers with uniform aramid units

    NARCIS (Netherlands)

    Niesten, M.C.E.J.

    2000-01-01

    Segmented copolymers with short, glassy or crystalline hard segments and long, amorphous soft segments (multi-block copolymers) are thermoplastic elastomers (TPE’s). The hard segments form physical crosslinks for the amorphous (rubbery) soft segments. As a result, this type of materials combines

  9. Quadratus lumborum block for post-operative pain relief in patient with Prune belly syndrome.

    Science.gov (United States)

    Garg, Chitra; Khanna, Sangeeta; Mehta, Yatin

    2017-10-01

    Abdominal field blocks are commonly used as part of multimodal analgesia for post-operative pain relief in patients undergoing abdominal surgery. Conventionally, transversus abdominis plane block is used, but has the disadvantage of limited spread only to T10-T12 segments, providing only partial pain relief. The new quadratus lumborum (QL) block has the advantage of providing wider sensory block from T6 to L1 and thus has an evolving role in opioid-free anaesthesia. Opioid-induced cough depression, urinary retention, and drowsiness can be problematic in patients with Prune belly syndrome, who have deficient abdominal muscles and myriad of genitourinary problems. We report a case of a young male with Prune belly syndrome, who had a pain-free post-operative period after high inguinal orchidectomy with unilateral QL block.

  10. Quadratus lumborum block for post-operative pain relief in patient with Prune belly syndrome

    Directory of Open Access Journals (Sweden)

    Chitra Garg

    2017-01-01

    Full Text Available Abdominal field blocks are commonly used as part of multimodal analgesia for post-operative pain relief in patients undergoing abdominal surgery. Conventionally, transversus abdominis plane block is used, but has the disadvantage of limited spread only to T10–T12 segments, providing only partial pain relief. The new quadratus lumborum (QL block has the advantage of providing wider sensory block from T6 to L1 and thus has an evolving role in opioid-free anaesthesia. Opioid-induced cough depression, urinary retention, and drowsiness can be problematic in patients with Prune belly syndrome, who have deficient abdominal muscles and myriad of genitourinary problems. We report a case of a young male with Prune belly syndrome, who had a pain-free post-operative period after high inguinal orchidectomy with unilateral QL block.

  11. Minimum Description Length Block Finder, a Method to Identify Haplotype Blocks and to Compare the Strength of Block Boundaries

    OpenAIRE

    Mannila, H.; Koivisto, M.; Perola, M.; Varilo, T.; Hennah, W.; Ekelund, J.; Lukk, M.; Peltonen, L.; Ukkonen, E.

    2003-01-01

    We describe a new probabilistic method for finding haplotype blocks that is based on the use of the minimum description length (MDL) principle. We give a rigorous definition of the quality of a segmentation of a genomic region into blocks and describe a dynamic programming algorithm for finding the optimal segmentation with respect to this measure. We also describe a method for finding the probability of a block boundary for each pair of adjacent markers: this gives a tool for evaluating the ...

  12. Active Segmentation.

    Science.gov (United States)

    Mishra, Ajay; Aloimonos, Yiannis

    2009-01-01

    The human visual system observes and understands a scene/image by making a series of fixations. Every fixation point lies inside a particular region of arbitrary shape and size in the scene which can either be an object or just a part of it. We define as a basic segmentation problem the task of segmenting that region containing the fixation point. Segmenting the region containing the fixation is equivalent to finding the enclosing contour- a connected set of boundary edge fragments in the edge map of the scene - around the fixation. This enclosing contour should be a depth boundary.We present here a novel algorithm that finds this bounding contour and achieves the segmentation of one object, given the fixation. The proposed segmentation framework combines monocular cues (color/intensity/texture) with stereo and/or motion, in a cue independent manner. The semantic robots of the immediate future will be able to use this algorithm to automatically find objects in any environment. The capability of automatically segmenting objects in their visual field can bring the visual processing to the next level. Our approach is different from current approaches. While existing work attempts to segment the whole scene at once into many areas, we segment only one image region, specifically the one containing the fixation point. Experiments with real imagery collected by our active robot and from the known databases 1 demonstrate the promise of the approach.

  13. Epidural block

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000484.htm Epidural block - pregnancy To use the sharing features on this page, please enable JavaScript. An epidural block is a numbing medicine given by injection (shot) ...

  14. Population Blocks.

    Science.gov (United States)

    Smith, Martin H.

    1992-01-01

    Describes an educational game called "Population Blocks" that is designed to illustrate the concept of exponential growth of the human population and some potential effects of overpopulation. The game material consists of wooden blocks; 18 blocks are painted green (representing land), 7 are painted blue (representing water); and the remaining…

  15. Segmentation: Identification of consumer segments

    DEFF Research Database (Denmark)

    Høg, Esben

    2005-01-01

    It is very common to categorise people, especially in the advertising business. Also traditional marketing theory has taken in consumer segments as a favorite topic. Segmentation is closely related to the broader concept of classification. From a historical point of view, classification has its...... origin in other sciences as for example biology, anthropology etc. From an economic point of view, it is called segmentation when specific scientific techniques are used to classify consumers to different characteristic groupings. What is the purpose of segmentation? For example, to be able to obtain...... a basic understanding of grouping people. Advertising agencies may use segmentation totarget advertisements, while food companies may usesegmentation to develop products to various groups of consumers. MAPP has for example investigated the positioning of fish in relation to other food products...

  16. Segmental Vitiligo.

    Science.gov (United States)

    van Geel, Nanja; Speeckaert, Reinhart

    2017-04-01

    Segmental vitiligo is characterized by its early onset, rapid stabilization, and unilateral distribution. Recent evidence suggests that segmental and nonsegmental vitiligo could represent variants of the same disease spectrum. Observational studies with respect to its distribution pattern point to a possible role of cutaneous mosaicism, whereas the original stated dermatomal distribution seems to be a misnomer. Although the exact pathogenic mechanism behind the melanocyte destruction is still unknown, increasing evidence has been published on the autoimmune/inflammatory theory of segmental vitiligo. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Joint shape segmentation with linear programming

    KAUST Repository

    Huang, Qixing

    2011-01-01

    We present an approach to segmenting shapes in a heterogenous shape database. Our approach segments the shapes jointly, utilizing features from multiple shapes to improve the segmentation of each. The approach is entirely unsupervised and is based on an integer quadratic programming formulation of the joint segmentation problem. The program optimizes over possible segmentations of individual shapes as well as over possible correspondences between segments from multiple shapes. The integer quadratic program is solved via a linear programming relaxation, using a block coordinate descent procedure that makes the optimization feasible for large databases. We evaluate the presented approach on the Princeton segmentation benchmark and show that joint shape segmentation significantly outperforms single-shape segmentation techniques. © 2011 ACM.

  18. Minimum description length block finder, a method to identify haplotype blocks and to compare the strength of block boundaries.

    Science.gov (United States)

    Mannila, H; Koivisto, M; Perola, M; Varilo, T; Hennah, W; Ekelund, J; Lukk, M; Peltonen, L; Ukkonen, E

    2003-07-01

    We describe a new probabilistic method for finding haplotype blocks that is based on the use of the minimum description length (MDL) principle. We give a rigorous definition of the quality of a segmentation of a genomic region into blocks and describe a dynamic programming algorithm for finding the optimal segmentation with respect to this measure. We also describe a method for finding the probability of a block boundary for each pair of adjacent markers: this gives a tool for evaluating the significance of each block boundary. We have applied the method to the published data of Daly and colleagues. The results expose some problems that exist in the current methods for the evaluation of the significance of predicted block boundaries. Our method, MDL block finder, can be used to compare block borders in different sample sets, and we demonstrate this by applying the MDL-based method to define the block structure in chromosomes from population isolates.

  19. Joint shape segmentation with linear programming

    KAUST Repository

    Huang, Qixing; Koltun, Vladlen; Guibas, Leonidas

    2011-01-01

    program is solved via a linear programming relaxation, using a block coordinate descent procedure that makes the optimization feasible for large databases. We evaluate the presented approach on the Princeton segmentation benchmark and show that joint shape

  20. Mixed segmentation

    DEFF Research Database (Denmark)

    Hansen, Allan Grutt; Bonde, Anders; Aagaard, Morten

    content analysis and audience segmentation in a single-source perspective. The aim is to explain and understand target groups in relation to, on the one hand, emotional response to commercials or other forms of audio-visual communication and, on the other hand, living preferences and personality traits...

  1. Market segmentation: Venezuelan ADRs

    Directory of Open Access Journals (Sweden)

    Urbi Garay

    2012-12-01

    Full Text Available The control on foreign exchange imposed by Venezuela in 2003 constitute a natural experiment that allows researchers to observe the effects of exchange controls on stock market segmentation. This paper provides empirical evidence that although the Venezuelan capital market as a whole was highly segmented before the controls were imposed, the shares in the firm CANTV were, through their American Depositary Receipts (ADRs, partially integrated with the global market. Following the imposition of the exchange controls this integration was lost. Research also documents the spectacular and apparently contradictory rise experienced by the Caracas Stock Exchange during the serious economic crisis of 2003. It is argued that, as it happened in Argentina in 2002, the rise in share prices occurred because the depreciation of the Bolívar in the parallel currency market increased the local price of the stocks that had associated ADRs, which were negotiated in dollars.

  2. Optimization of partial search

    International Nuclear Information System (INIS)

    Korepin, Vladimir E

    2005-01-01

    A quantum Grover search algorithm can find a target item in a database faster than any classical algorithm. One can trade accuracy for speed and find a part of the database (a block) containing the target item even faster; this is partial search. A partial search algorithm was recently suggested by Grover and Radhakrishnan. Here we optimize it. Efficiency of the search algorithm is measured by the number of queries to the oracle. The author suggests a new version of the Grover-Radhakrishnan algorithm which uses a minimal number of such queries. The algorithm can run on the same hardware that is used for the usual Grover algorithm. (letter to the editor)

  3. Anatomic partial nephrectomy: technique evolution.

    Science.gov (United States)

    Azhar, Raed A; Metcalfe, Charles; Gill, Inderbir S

    2015-03-01

    Partial nephrectomy provides equivalent long-term oncologic and superior functional outcomes as radical nephrectomy for T1a renal masses. Herein, we review the various vascular clamping techniques employed during minimally invasive partial nephrectomy, describe the evolution of our partial nephrectomy technique and provide an update on contemporary thinking about the impact of ischemia on renal function. Recently, partial nephrectomy surgical technique has shifted away from main artery clamping and towards minimizing/eliminating global renal ischemia during partial nephrectomy. Supported by high-fidelity three-dimensional imaging, novel anatomic-based partial nephrectomy techniques have recently been developed, wherein partial nephrectomy can now be performed with segmental, minimal or zero global ischemia to the renal remnant. Sequential innovations have included early unclamping, segmental clamping, super-selective clamping and now culminating in anatomic zero-ischemia surgery. By eliminating 'under-the-gun' time pressure of ischemia for the surgeon, these techniques allow an unhurried, tightly contoured tumour excision with point-specific sutured haemostasis. Recent data indicate that zero-ischemia partial nephrectomy may provide better functional outcomes by minimizing/eliminating global ischemia and preserving greater vascularized kidney volume. Contemporary partial nephrectomy includes a spectrum of surgical techniques ranging from conventional-clamped to novel zero-ischemia approaches. Technique selection should be tailored to each individual case on the basis of tumour characteristics, surgical feasibility, surgeon experience, patient demographics and baseline renal function.

  4. Detection block

    International Nuclear Information System (INIS)

    Bezak, A.

    1987-01-01

    A diagram is given of a detection block used for monitoring burnup of nuclear reactor fuel. A shielding block is an important part of the detection block. It stabilizes the fuel assembly in the fixing hole in front of a collimator where a suitable gamma beam is defined for gamma spectrometry determination of fuel burnup. The detector case and a neutron source case are placed on opposite sides of the fixing hole. For neutron measurement for which the water in the tank is used as a moderator, the neutron detector-fuel assembly configuration is selected such that neutrons from spontaneous fission and neutrons induced with the neutron source can both be measured. The patented design of the detection block permits longitudinal travel and rotation of the fuel assembly to any position, and thus more reliable determination of nuclear fuel burnup. (E.S.). 1 fig

  5. Raquianestesia contínua em paciente submetido à gastrectomia parcial: relato de caso Raquianestesia continua en paciente sometido a la gastrectomía parcial: relato de caso Continuous spinal block in a patient undergoing partial gastrectomy: case report

    Directory of Open Access Journals (Sweden)

    Patrícia Falcão Pitombo

    2009-08-01

    , continuous spinal blocks were not performed for several years. With the advent of intermediate catheters the technique has been used more often and gaining acceptance among anesthesiologists. The objective of this report was to demonstrate the usefulness of the technique as a viable alternative for medium and major size surgeries. CASE REPORT: This is a 58 years old female patient, weighing 62 kg, physical status ASA I, with a history of migraines, low back pain, and prior surgeries under spinal block without intercurrence. The patient was scheduled for exploratory laparotomy for a probable pelvic tumor. After venoclysis with an 18G catheter, monitoring with cardioscope, non-invasive blood pressure and pulse oximetry was instituted; she was sedated with 2 mg of midazolam and 100 ¼g of fentanyl, and placed in left lateral decubitus. The patient underwent continuous spinal block through the median approach in L3-L4; 9 mg of 0.5% hyperbaric bupivacaine and 120 ¼g of morphine sulfate were administered. Inspection of the abdominal cavity revealed a gastric stromal tumor that required an increase in the incision for a partial gastrectomy. A small dose of hyperbaric solution was required for the entire procedure, which was associated with complete hemodynamic stability. Postoperative admission to the ICU was not necessary; the patient presented a good evolution without complaints and with a high degree of satisfaction. She was discharged from the hospital after 72 hours without intercurrence. CONCLUSIONS: Intermediate catheters used in continuous spinal blocks have shown the potential to turn it an attractive and useful technique in medium and large size surgeries and it can even be an effective alternative in the management of critical patients to whom hemodynamic repercussions can be harmful.

  6. Brookhaven segment interconnect

    International Nuclear Information System (INIS)

    Morse, W.M.; Benenson, G.; Leipuner, L.B.

    1983-01-01

    We have performed a high energy physics experiment using a multisegment Brookhaven FASTBUS system. The system was composed of three crate segments and two cable segments. We discuss the segment interconnect module which permits communication between the various segments

  7. Blocking sets in Desarguesian planes

    NARCIS (Netherlands)

    Blokhuis, A.; Miklós, D.; Sós, V.T.; Szönyi, T.

    1996-01-01

    We survey recent results concerning the size of blocking sets in desarguesian projective and affine planes, and implications of these results and the technique to prove them, to related problemis, such as the size of maximal partial spreads, small complete arcs, small strong representative systems

  8. Immediate haemodynamic effects of a novel partial agonist, beta 1-adrenoceptor blocking drug ICI 141,292 after intravenous administration to healthy young volunteers and patients with ischaemic heart disease

    DEFF Research Database (Denmark)

    Bonde, J; Svendsen, T L; Lyngborg, K

    1987-01-01

    administration of four sequential doses (0.5, 0.5, 1.0 and 2.0 mg) of ICI 141,292 was examined. HR decreased 7% (P less than 0.05) following ICI 141,292 1 mg with no further decrease following the succeeding doses. Cardiac output decreased 5.2% (P less than 0.05) following a cumulative dose of 4 mg...... as atenolol) beta 1-adrenoceptor blocking agent possessing moderate intrinsic sympathomimetic activity....

  9. Ameliorative Effects of Neurolytic Celiac Plexus Block on Stress and ...

    African Journals Online (AJOL)

    Keywords: Neurolytic celiac plexus block, Cytokine, Nuclear translocation, Partial hepatectomy, Stress, ... International Pharmaceutical Abstract, Chemical Abstracts, Embase, Index ... inflammatory reactions, leading to over-activation.

  10. Partial Cancellation

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Partial Cancellation. Full Cancellation is desirable. But complexity requirements are enormous. 4000 tones, 100 Users billions of flops !!! Main Idea: Challenge: To determine which cross-talker to cancel on what “tone” for a given victim. Constraint: Total complexity is ...

  11. Partial processing

    International Nuclear Information System (INIS)

    1978-11-01

    This discussion paper considers the possibility of applying to the recycle of plutonium in thermal reactors a particular method of partial processing based on the PUREX process but named CIVEX to emphasise the differences. The CIVEX process is based primarily on the retention of short-lived fission products. The paper suggests: (1) the recycle of fission products with uranium and plutonium in thermal reactor fuel would be technically feasible; (2) it would, however, take ten years or more to develop the CIVEX process to the point where it could be launched on a commercial scale; (3) since the majority of spent fuel to be reprocessed this century will have been in storage for ten years or more, the recycling of short-lived fission products with the U-Pu would not provide an effective means of making refabrication fuel ''inaccessible'' because the radioactivity associated with the fission products would have decayed. There would therefore be no advantage in partial processing

  12. Partial gigantism

    Directory of Open Access Journals (Sweden)

    М.М. Karimova

    2017-05-01

    Full Text Available A girl with partial gigantism (the increased I and II fingers of the left foot is being examined. This condition is a rare and unresolved problem, as the definite reason of its development is not determined. Wait-and-see strategy is recommended, as well as correcting operations after closing of growth zones, and forming of data pool for generalization and development of schemes of drug and radial therapeutic methods.

  13. An efficient, block-by-block algorithm for inverting a block tridiagonal, nearly block Toeplitz matrix

    International Nuclear Information System (INIS)

    Reuter, Matthew G; Hill, Judith C

    2012-01-01

    We present an algorithm for computing any block of the inverse of a block tridiagonal, nearly block Toeplitz matrix (defined as a block tridiagonal matrix with a small number of deviations from the purely block Toeplitz structure). By exploiting both the block tridiagonal and the nearly block Toeplitz structures, this method scales independently of the total number of blocks in the matrix and linearly with the number of deviations. Numerical studies demonstrate this scaling and the advantages of our method over alternatives.

  14. Unsupervised motion-based object segmentation refined by color

    Science.gov (United States)

    Piek, Matthijs C.; Braspenning, Ralph; Varekamp, Chris

    2003-06-01

    For various applications, such as data compression, structure from motion, medical imaging and video enhancement, there is a need for an algorithm that divides video sequences into independently moving objects. Because our focus is on video enhancement and structure from motion for consumer electronics, we strive for a low complexity solution. For still images, several approaches exist based on colour, but these lack in both speed and segmentation quality. For instance, colour-based watershed algorithms produce a so-called oversegmentation with many segments covering each single physical object. Other colour segmentation approaches exist which somehow limit the number of segments to reduce this oversegmentation problem. However, this often results in inaccurate edges or even missed objects. Most likely, colour is an inherently insufficient cue for real world object segmentation, because real world objects can display complex combinations of colours. For video sequences, however, an additional cue is available, namely the motion of objects. When different objects in a scene have different motion, the motion cue alone is often enough to reliably distinguish objects from one another and the background. However, because of the lack of sufficient resolution of efficient motion estimators, like the 3DRS block matcher, the resulting segmentation is not at pixel resolution, but at block resolution. Existing pixel resolution motion estimators are more sensitive to noise, suffer more from aperture problems or have less correspondence to the true motion of objects when compared to block-based approaches or are too computationally expensive. From its tendency to oversegmentation it is apparent that colour segmentation is particularly effective near edges of homogeneously coloured areas. On the other hand, block-based true motion estimation is particularly effective in heterogeneous areas, because heterogeneous areas improve the chance a block is unique and thus decrease the

  15. Analysis of Block OMP using Block RIP

    OpenAIRE

    Wang, Jun; Li, Gang; Zhang, Hao; Wang, Xiqin

    2011-01-01

    Orthogonal matching pursuit (OMP) is a canonical greedy algorithm for sparse signal reconstruction. When the signal of interest is block sparse, i.e., it has nonzero coefficients occurring in clusters, the block version of OMP algorithm (i.e., Block OMP) outperforms the conventional OMP. In this paper, we demonstrate that a new notion of block restricted isometry property (Block RIP), which is less stringent than standard restricted isometry property (RIP), can be used for a very straightforw...

  16. Comparação da anestesia geral e bloqueio do plexo cervical superficial em tireoidectomias parciais Comparison between general anesthesia and superficial cervical plexus block in partial thyroidectomies

    Directory of Open Access Journals (Sweden)

    Rui Celso Martins Mamede

    2008-02-01

    Full Text Available Tireoidectomia sob efeito de bloqueio do plexo cervical superficial (BPCS tem sofrido resistência. OBJETIVO: Comparar variáveis cirúrgicas e anestésicas, custos do tratamento e grau de satisfação de pacientes submetidos à hemitireoidectomia sob efeito de anestesia geral e BPCS. CASUÍSTICA E MÉTODOS: Foram 21 pacientes submetidos à anestesia geral (AG e outro tanto ao BPCS. Após sedação, no grupo com BPCS, usou-se marcaína com vasoconstritor, e quando necessário, lidocaína a 2% com vasoconstritor. Sedação intra-operatória com diazepam endovenoso e metoprolol para controle da PA e FC eram administradas quando necessário. Usou-se anestesia geral (AG segundo padronização do serviço. RESULTADOS: Foram significantes (pThyroidectomy under the effect of superficial cervical plexus block (SCPB has met resistance. AIM: to compare variables in patients submitted to hemithyroidectomy under the effect of general anesthesia (GA and SCPB. CASE REPORT AND METHODS: GA was used in 21 patients, and SCPB was used in another 21 patients. Following sedation, marcaine 0.5% with vasoconstrictor was used in the SCPB group. Intraoperative sedation with diazepam and metoprolol to control arterial pressure and cardiac frequency was given as needed. GA followed the standard method in the unit. RESULTS: We found significant results (p<0.05, Student’s t-test for surgery time (GA - 111.4 min; SCPB - 125.5 min, anesthesia time (GA - 154.1 min; SCPB - 488.6 min, time in the surgery room (GA - 15 min; SCPB - 1 min, treatment costs (GA - R$203.2; SCPB - R$87.4, presence of bradycardia (GA - 0; SCPB - 23.8% and laryngotracheal injury (GA - 51; SCPB - 0 %. We also found the following non-significant results: hospitalization time (GA - 17.3; SCPB - 15.1 hours; bleeding volume (GA - 41,9 g; SCPB - 47.6 g, size of the operative specimen (GA - 52.1 cm3; SCPB - 93.69 cm3 and patient satisfaction level (GA - 3.8; SCPB - 3.9. CONCLUSION: Although the incidence of

  17. Isostatic compression of buffer blocks. Middle scale

    International Nuclear Information System (INIS)

    Ritola, J.; Pyy, E.

    2012-01-01

    Manufacturing of buffer components using isostatic compression method has been studied in small scale in 2008 (Laaksonen 2010). These tests included manufacturing of buffer blocks using different bentonite materials and different compression pressures. Isostatic mould technology was also tested, along with different methods to fill the mould, such as vibration and partial vacuum, as well as a stepwise compression of the blocks. The development of manufacturing techniques has continued with small-scale (30 %) blocks (diameter 600 mm) in 2009. This was done in a separate project: Isostatic compression, manufacturing and testing of small scale (D = 600 mm) buffer blocks. The research on the isostatic compression method continued in 2010 in a project aimed to test and examine the isostatic manufacturing process of buffer blocks at 70 % scale (block diameter 1200 to 1300 mm), and the aim was to continue in 2011 with full-scale blocks (diameter 1700 mm). A total of nine bentonite blocks were manufactured at 70 % scale, of which four were ring-shaped and the rest were cylindrical. It is currently not possible to manufacture full-scale blocks, because there is no sufficiently large isostatic press available. However, such a compression unit is expected to be possible to use in the near future. The test results of bentonite blocks, produced with an isostatic pressing method at different presses and at different sizes, suggest that the technical characteristics, for example bulk density and strength values, are somewhat independent of the size of the block, and that the blocks have fairly homogenous characteristics. Water content and compression pressure are the two most important properties determining the characteristics of the compressed blocks. By adjusting these two properties it is fairly easy to produce blocks at a desired density. The commonly used compression pressure in the manufacturing of bentonite blocks is 100 MPa, which compresses bentonite to approximately

  18. Isostatic compression of buffer blocks. Middle scale

    Energy Technology Data Exchange (ETDEWEB)

    Ritola, J.; Pyy, E. [VTT Technical Research Centre of Finland, Espoo (Finland)

    2012-01-15

    Manufacturing of buffer components using isostatic compression method has been studied in small scale in 2008 (Laaksonen 2010). These tests included manufacturing of buffer blocks using different bentonite materials and different compression pressures. Isostatic mould technology was also tested, along with different methods to fill the mould, such as vibration and partial vacuum, as well as a stepwise compression of the blocks. The development of manufacturing techniques has continued with small-scale (30 %) blocks (diameter 600 mm) in 2009. This was done in a separate project: Isostatic compression, manufacturing and testing of small scale (D = 600 mm) buffer blocks. The research on the isostatic compression method continued in 2010 in a project aimed to test and examine the isostatic manufacturing process of buffer blocks at 70 % scale (block diameter 1200 to 1300 mm), and the aim was to continue in 2011 with full-scale blocks (diameter 1700 mm). A total of nine bentonite blocks were manufactured at 70 % scale, of which four were ring-shaped and the rest were cylindrical. It is currently not possible to manufacture full-scale blocks, because there is no sufficiently large isostatic press available. However, such a compression unit is expected to be possible to use in the near future. The test results of bentonite blocks, produced with an isostatic pressing method at different presses and at different sizes, suggest that the technical characteristics, for example bulk density and strength values, are somewhat independent of the size of the block, and that the blocks have fairly homogenous characteristics. Water content and compression pressure are the two most important properties determining the characteristics of the compressed blocks. By adjusting these two properties it is fairly easy to produce blocks at a desired density. The commonly used compression pressure in the manufacturing of bentonite blocks is 100 MPa, which compresses bentonite to approximately

  19. Segmented trapped vortex cavity

    Science.gov (United States)

    Grammel, Jr., Leonard Paul (Inventor); Pennekamp, David Lance (Inventor); Winslow, Jr., Ralph Henry (Inventor)

    2010-01-01

    An annular trapped vortex cavity assembly segment comprising includes a cavity forward wall, a cavity aft wall, and a cavity radially outer wall there between defining a cavity segment therein. A cavity opening extends between the forward and aft walls at a radially inner end of the assembly segment. Radially spaced apart pluralities of air injection first and second holes extend through the forward and aft walls respectively. The segment may include first and second expansion joint features at distal first and second ends respectively of the segment. The segment may include a forward subcomponent including the cavity forward wall attached to an aft subcomponent including the cavity aft wall. The forward and aft subcomponents include forward and aft portions of the cavity radially outer wall respectively. A ring of the segments may be circumferentially disposed about an axis to form an annular segmented vortex cavity assembly.

  20. Pavement management segment consolidation

    Science.gov (United States)

    1998-01-01

    Dividing roads into "homogeneous" segments has been a major problem for all areas of highway engineering. SDDOT uses Deighton Associates Limited software, dTIMS, to analyze life-cycle costs for various rehabilitation strategies on each segment of roa...

  1. Speaker segmentation and clustering

    OpenAIRE

    Kotti, M; Moschou, V; Kotropoulos, C

    2008-01-01

    07.08.13 KB. Ok to add the accepted version to Spiral, Elsevier says ok whlile mandate not enforced. This survey focuses on two challenging speech processing topics, namely: speaker segmentation and speaker clustering. Speaker segmentation aims at finding speaker change points in an audio stream, whereas speaker clustering aims at grouping speech segments based on speaker characteristics. Model-based, metric-based, and hybrid speaker segmentation algorithms are reviewed. Concerning speaker...

  2. Spinal segmental dysgenesis

    Directory of Open Access Journals (Sweden)

    N Mahomed

    2009-06-01

    Full Text Available Spinal segmental dysgenesis is a rare congenital spinal abnormality , seen in neonates and infants in which a segment of the spine and spinal cord fails to develop normally . The condition is segmental with normal vertebrae above and below the malformation. This condition is commonly associated with various abnormalities that affect the heart, genitourinary, gastrointestinal tract and skeletal system. We report two cases of spinal segmental dysgenesis and the associated abnormalities.

  3. Ultrasound guided supraclavicular block.

    LENUS (Irish Health Repository)

    Hanumanthaiah, Deepak

    2013-09-01

    Ultrasound guided regional anaesthesia is becoming increasingly popular. The supraclavicular block has been transformed by ultrasound guidance into a potentially safe superficial block. We reviewed the techniques of performing supraclavicular block with special focus on ultrasound guidance.

  4. Cochlea Segmentation using Iterated Random Walks with Shape Prior

    DEFF Research Database (Denmark)

    Ruiz Pujadas, Esmeralda; Kjer, Hans Martin; Vera, Sergio

    2016-01-01

    Cochlear implants can restore hearing to deaf or partially deaf patients. In order to plan the intervention, a model from high resolution μCT images is to be built from accurate cochlea segmentations and then, adapted to a patient-specific model. Thus, a precise segmentation is required to build...

  5. Automatic Melody Segmentation

    NARCIS (Netherlands)

    Rodríguez López, Marcelo

    2016-01-01

    The work presented in this dissertation investigates music segmentation. In the field of Musicology, segmentation refers to a score analysis technique, whereby notated pieces or passages of these pieces are divided into “units” referred to as sections, periods, phrases, and so on. Segmentation

  6. Segmentation and Location Computation of Bin Objects

    Directory of Open Access Journals (Sweden)

    C.R. Hema

    2008-11-01

    Full Text Available In this paper we present a stereo vision based system for segmentation and location computation of partially occluded objects in bin picking environments. Algorithms to segment partially occluded objects and to find the object location [midpoint,x, y and z coordinates] with respect to the bin area are proposed. The z co ordinate is computed using stereo images and neural networks. The proposed algorithms is tested using two neural network architectures namely the Radial Basis Function nets and Simple Feedforward nets. The training results fo feedforward nets are found to be more suitable for the current application.The proposed stereo vision system is interfaced with an Adept SCARA Robot to perform bin picking operations. The vision system is found to be effective for partially occluded objects, in the absence of albedo effects. The results are validated through real time bin picking experiments on the Adept Robot.

  7. The diagnosis of blocked pulmonary abscess

    International Nuclear Information System (INIS)

    Vinner, M.G.; Khudyakov, L.M.; Mezentsev, I.A.

    1992-01-01

    Only spot bronchography, and if its results are negative, transthoracal puncture permit a correct diagnosis of blocked or partially blocked pulmonary abscess in 2/3 of cases. This result is of importance for the choice of the treatment strategy, in such patients. Use of thin or super-thin needles for puncture helped do without serious complications and obtain reliable diagnostic information in 90 % of cases

  8. Bayesian automated cortical segmentation for neonatal MRI

    Science.gov (United States)

    Chou, Zane; Paquette, Natacha; Ganesh, Bhavana; Wang, Yalin; Ceschin, Rafael; Nelson, Marvin D.; Macyszyn, Luke; Gaonkar, Bilwaj; Panigrahy, Ashok; Lepore, Natasha

    2017-11-01

    Several attempts have been made in the past few years to develop and implement an automated segmentation of neonatal brain structural MRI. However, accurate automated MRI segmentation remains challenging in this population because of the low signal-to-noise ratio, large partial volume effects and inter-individual anatomical variability of the neonatal brain. In this paper, we propose a learning method for segmenting the whole brain cortical grey matter on neonatal T2-weighted images. We trained our algorithm using a neonatal dataset composed of 3 fullterm and 4 preterm infants scanned at term equivalent age. Our segmentation pipeline combines the FAST algorithm from the FSL library software and a Bayesian segmentation approach to create a threshold matrix that minimizes the error of mislabeling brain tissue types. Our method shows promising results with our pilot training set. In both preterm and full-term neonates, automated Bayesian segmentation generates a smoother and more consistent parcellation compared to FAST, while successfully removing the subcortical structure and cleaning the edges of the cortical grey matter. This method show promising refinement of the FAST segmentation by considerably reducing manual input and editing required from the user, and further improving reliability and processing time of neonatal MR images. Further improvement will include a larger dataset of training images acquired from different manufacturers.

  9. Partial avascular necrosis after talar neck fracture.

    Science.gov (United States)

    Babu, Nina; Schuberth, John M

    2010-09-01

    Recently, it has been shown that avascular necrosis of the talus can occur in only a portion of the talar body. There is little information regarding the geographic location of the avascular segment and the clinical significance of an incomplete avascular process. Seven patients with partial avascular necrosis after Hawkins type II or III fracture dislocations were evaluated with magnetic resonance scans. The precise anatomic location of the avascular segment was determined and assigned to a specific quadrant of the talar body. The operative exposure, incidence of collapse, and time to operative intervention was recorded. The avascular segment of the talar body was located predominantly in the anterior lateral and superior portion in six of the seven patients. Collapse occurred in three of the patients in the area of avascular process. There were no observable trends with regard to operative exposure, Hawkins classification, incidence of collapse, or time to operative intervention to the location of the avascular segment. Partial avascular necrosis can occur after fracture dislocation of the talus. The predominant location of the avascular segment was the anterior lateral and superior portion of the talar body. This observation corresponds to regional damage to the blood supply of the talus and may help clarify the pathogenesis of partial avascular process.

  10. Segmentation, Inference and Classification of Partially Overlapping Nanoparticles

    KAUST Repository

    Chiwoo Park,; Huang, J. Z.; Ji, J. X.; Yu Ding,

    2013-01-01

    an agglomerate of overlapping nano-objects; infer the particle's missing contours; and ultimately, classify the particles by shape based on their complete contours. Our specific method adopts a two-stage approach: the first stage executes the task of particle

  11. 3D Reasoning from Blocks to Stability.

    Science.gov (United States)

    Zhaoyin Jia; Gallagher, Andrew C; Saxena, Ashutosh; Chen, Tsuhan

    2015-05-01

    Objects occupy physical space and obey physical laws. To truly understand a scene, we must reason about the space that objects in it occupy, and how each objects is supported stably by each other. In other words, we seek to understand which objects would, if moved, cause other objects to fall. This 3D volumetric reasoning is important for many scene understanding tasks, ranging from segmentation of objects to perception of a rich 3D, physically well-founded, interpretations of the scene. In this paper, we propose a new algorithm to parse a single RGB-D image with 3D block units while jointly reasoning about the segments, volumes, supporting relationships, and object stability. Our algorithm is based on the intuition that a good 3D representation of the scene is one that fits the depth data well, and is a stable, self-supporting arrangement of objects (i.e., one that does not topple). We design an energy function for representing the quality of the block representation based on these properties. Our algorithm fits 3D blocks to the depth values corresponding to image segments, and iteratively optimizes the energy function. Our proposed algorithm is the first to consider stability of objects in complex arrangements for reasoning about the underlying structure of the scene. Experimental results show that our stability-reasoning framework improves RGB-D segmentation and scene volumetric representation.

  12. Homogeneous bilateral block shifts

    Indian Academy of Sciences (India)

    Douglas class were classified in [3]; they are unilateral block shifts of arbitrary block size (i.e. dim H(n) can be anything). However, no examples of irreducible homogeneous bilateral block shifts of block size larger than 1 were known until now.

  13. Light extraction block with curved surface

    Science.gov (United States)

    Levermore, Peter; Krall, Emory; Silvernail, Jeffrey; Rajan, Kamala; Brown, Julia J.

    2016-03-22

    Light extraction blocks, and OLED lighting panels using light extraction blocks, are described, in which the light extraction blocks include various curved shapes that provide improved light extraction properties compared to parallel emissive surface, and a thinner form factor and better light extraction than a hemisphere. Lighting systems described herein may include a light source with an OLED panel. A light extraction block with a three-dimensional light emitting surface may be optically coupled to the light source. The three-dimensional light emitting surface of the block may includes a substantially curved surface, with further characteristics related to the curvature of the surface at given points. A first radius of curvature corresponding to a maximum principal curvature k.sub.1 at a point p on the substantially curved surface may be greater than a maximum height of the light extraction block. A maximum height of the light extraction block may be less than 50% of a maximum width of the light extraction block. Surfaces with cross sections made up of line segments and inflection points may also be fit to approximated curves for calculating the radius of curvature.

  14. Testing block subdivision algorithms on block designs

    Science.gov (United States)

    Wiseman, Natalie; Patterson, Zachary

    2016-01-01

    Integrated land use-transportation models predict future transportation demand taking into account how households and firms arrange themselves partly as a function of the transportation system. Recent integrated models require parcels as inputs and produce household and employment predictions at the parcel scale. Block subdivision algorithms automatically generate parcel patterns within blocks. Evaluating block subdivision algorithms is done by way of generating parcels and comparing them to those in a parcel database. Three block subdivision algorithms are evaluated on how closely they reproduce parcels of different block types found in a parcel database from Montreal, Canada. While the authors who developed each of the algorithms have evaluated them, they have used their own metrics and block types to evaluate their own algorithms. This makes it difficult to compare their strengths and weaknesses. The contribution of this paper is in resolving this difficulty with the aim of finding a better algorithm suited to subdividing each block type. The proposed hypothesis is that given the different approaches that block subdivision algorithms take, it's likely that different algorithms are better adapted to subdividing different block types. To test this, a standardized block type classification is used that consists of mutually exclusive and comprehensive categories. A statistical method is used for finding a better algorithm and the probability it will perform well for a given block type. Results suggest the oriented bounding box algorithm performs better for warped non-uniform sites, as well as gridiron and fragmented uniform sites. It also produces more similar parcel areas and widths. The Generalized Parcel Divider 1 algorithm performs better for gridiron non-uniform sites. The Straight Skeleton algorithm performs better for loop and lollipop networks as well as fragmented non-uniform and warped uniform sites. It also produces more similar parcel shapes and patterns.

  15. SEGMENTAL EPIDURAL ANAESTHESIA FOR INGUINAL HERNIA REPAIR

    Directory of Open Access Journals (Sweden)

    Sachidanand

    2015-09-01

    Full Text Available BACKGROUND: Epidural anaesthesia is suitable as a sole agent for lower abdominal surgery and surgery on lower limbs. It has some definite advantages over spinal anaesthesia like avoidance of post spinal headache, minimal chances of meningitis, and minimal chances of nausea and vomiting in postoperative period. But administration of conventional dosage of local epidural anaesthetics (15ml and above for surgical anaesthesia frequently results in multiple hemodynamic changes, including decreases in chronotropism, inotro pism, dromotropism, systemic vascular resistance, cardiac output, and myocardial oxygen consumption. The segmental epidural block denotes the use of a small volume enough to block only the segments involved in the field of surgery. AIM: To study the effect iveness of segmental epidural anaesthesia for inguinal hernia repair. DESIGN: R andomized control study. METHODS: 100 pts belonging to ASA PS I & II posted for inguinal hernia repair given 5ml of 0.5% bupivacaine through epidural route at L1 - L2 level and a fter conforming the adequacy and level of analgesia, the surgery was commenced. If the patient complained of pain during needle prick, then injected local anaesthetic (0.5% Bupivacaine with an incremental dosage of 1ml at a time, till the complete onset o f analgesia Pulse Rate and Blood Pressure were recorded at an interval of 1 minute for first 5 minutes and then every 5 minutes till the end of the surgery. Oxygen saturation and ECG monitoring was done continuously. Onset of analgesia, level of analgesia ( P re & post operatively, duration of analgesia, total dosage of local anaesthetic used were recorded. Complications like bradycardia, hypotension, respiratory depression, shivering, nausea and vomiting, sweating and inadvertent dural puncture were recorde d. RESULTS: 53% of patients had excellent quality of analgesia and relaxation. 34% patients had good quality analgesia and relaxation, mild discomfort while handling sac

  16. Poly(ferrocenylsilane)-block-Polylactide Block Copolymers

    NARCIS (Netherlands)

    Roerdink, M.; van Zanten, Thomas S.; Hempenius, Mark A.; Zhong, Zhiyuan; Feijen, Jan; Vancso, Gyula J.

    2007-01-01

    A PFS/PLA block copolymer was studied to probe the effect of strong surface interactions on pattern formation in PFS block copolymer thin films. Successful synthesis of PFS-b-PLA was demonstrated. Thin films of these polymers show phase separation to form PFS microdomains in a PLA matrix, and

  17. Phase Separation and Elastic Properties of Poly(Trimethylene Terephthalate)-block-poly(Ethylene Oxide) Copolymers

    OpenAIRE

    Elżbieta Piesowicz; Sandra Paszkiewicz; Anna Szymczyk

    2016-01-01

    A series of poly(trimethylene terephthalate)-block-poly(ethylene oxide) (PTT-b-PEOT) copolymers with different compositions of rigid PTT and flexible PEOT segments were synthesized via condensation in the melt. The influence of the block length and the block ratio on the micro-separated phase structure and elastic properties of the synthesized multiblock copolymers was studied. The PEOT segments in these copolymers were kept constant at 1130, 2130 or 3130 g/mol, whereas the PTT content varied...

  18. Underwater Object Segmentation Based on Optical Features

    Directory of Open Access Journals (Sweden)

    Zhe Chen

    2018-01-01

    Full Text Available Underwater optical environments are seriously affected by various optical inputs, such as artificial light, sky light, and ambient scattered light. The latter two can block underwater object segmentation tasks, since they inhibit the emergence of objects of interest and distort image information, while artificial light can contribute to segmentation. Artificial light often focuses on the object of interest, and, therefore, we can initially identify the region of target objects if the collimation of artificial light is recognized. Based on this concept, we propose an optical feature extraction, calculation, and decision method to identify the collimated region of artificial light as a candidate object region. Then, the second phase employs a level set method to segment the objects of interest within the candidate region. This two-phase structure largely removes background noise and highlights the outline of underwater objects. We test the performance of the method with diverse underwater datasets, demonstrating that it outperforms previous methods.

  19. A conserved segmental duplication within ELA.

    Science.gov (United States)

    Brinkmeyer-Langford, C L; Murphy, W J; Childers, C P; Skow, L C

    2010-12-01

    The assembled genomic sequence of the horse major histocompatibility complex (MHC) (equine lymphocyte antigen, ELA) is very similar to the homologous human HLA, with the notable exception of a large segmental duplication at the boundary of ELA class I and class III that is absent in HLA. The segmental duplication consists of a ∼ 710 kb region of at least 11 repeated blocks: 10 blocks each contain an MHC class I-like sequence and the helicase domain portion of a BAT1-like sequence, and the remaining unit contains the full-length BAT1 gene. Similar genomic features were found in other Perissodactyls, indicating an ancient origin, which is consistent with phylogenetic analyses. Reverse-transcriptase PCR (RT-PCR) of mRNA from peripheral white blood cells of healthy and chronically or acutely infected horses detected transcription from predicted open reading frames in several of the duplicated blocks. This duplication is not present in the sequenced MHCs of most other mammals, although a similar feature at the same relative position is present in the feline MHC (FLA). Striking sequence conservation throughout Perissodactyl evolution is consistent with a functional role for at least some of the genes included within this segmental duplication. © 2010 The Authors, Journal compilation © 2010 Stichting International Foundation for Animal Genetics.

  20. Segmentation of knee injury swelling on infrared images

    Science.gov (United States)

    Puentes, John; Langet, Hélène; Herry, Christophe; Frize, Monique

    2011-03-01

    Interpretation of medical infrared images is complex due to thermal noise, absence of texture, and small temperature differences in pathological zones. Acute inflammatory response is a characteristic symptom of some knee injuries like anterior cruciate ligament sprains, muscle or tendons strains, and meniscus tear. Whereas artificial coloring of the original grey level images may allow to visually assess the extent inflammation in the area, their automated segmentation remains a challenging problem. This paper presents a hybrid segmentation algorithm to evaluate the extent of inflammation after knee injury, in terms of temperature variations and surface shape. It is based on the intersection of rapid color segmentation and homogeneous region segmentation, to which a Laplacian of a Gaussian filter is applied. While rapid color segmentation enables to properly detect the observed core of swollen area, homogeneous region segmentation identifies possible inflammation zones, combining homogeneous grey level and hue area segmentation. The hybrid segmentation algorithm compares the potential inflammation regions partially detected by each method to identify overlapping areas. Noise filtering and edge segmentation are then applied to common zones in order to segment the swelling surfaces of the injury. Experimental results on images of a patient with anterior cruciate ligament sprain show the improved performance of the hybrid algorithm with respect to its separated components. The main contribution of this work is a meaningful automatic segmentation of abnormal skin temperature variations on infrared thermography images of knee injury swelling.

  1. Fast processing of foreign fiber images by image blocking

    Directory of Open Access Journals (Sweden)

    Yutao Wu

    2014-08-01

    Full Text Available In the textile industry, it is always the case that cotton products are constitutive of many types of foreign fibers which affect the overall quality of cotton products. As the foundation of the foreign fiber automated inspection, image process exerts a critical impact on the process of foreign fiber identification. This paper presents a new approach for the fast processing of foreign fiber images. This approach includes five main steps, image block, image pre-decision, image background extraction, image enhancement and segmentation, and image connection. At first, the captured color images were transformed into gray-scale images; followed by the inversion of gray-scale of the transformed images ; then the whole image was divided into several blocks. Thereafter, the subsequent step is to judge which image block contains the target foreign fiber image through image pre-decision. Then we segment the image block via OSTU which possibly contains target images after background eradication and image strengthening. Finally, we connect those relevant segmented image blocks to get an intact and clear foreign fiber target image. The experimental result shows that this method of segmentation has the advantage of accuracy and speed over the other segmentation methods. On the other hand, this method also connects the target image that produce fractures therefore getting an intact and clear foreign fiber target image.

  2. Segmentation, advertising and prices

    NARCIS (Netherlands)

    Galeotti, Andrea; Moraga González, José

    This paper explores the implications of market segmentation on firm competitiveness. In contrast to earlier work, here market segmentation is minimal in the sense that it is based on consumer attributes that are completely unrelated to tastes. We show that when the market is comprised by two

  3. Sipunculans and segmentation

    DEFF Research Database (Denmark)

    Wanninger, Andreas; Kristof, Alen; Brinkmann, Nora

    2009-01-01

    mechanisms may act on the level of gene expression, cell proliferation, tissue differentiation and organ system formation in individual segments. Accordingly, in some polychaete annelids the first three pairs of segmental peripheral neurons arise synchronously, while the metameric commissures of the ventral...

  4. Block That Pain!

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues Block That Pain! Past Issues / Fall 2007 Table of ... contrast, most pain relievers used for surgical procedures block activity in all types of neurons. This can ...

  5. Bundle Branch Block

    Science.gov (United States)

    ... known cause. Causes can include: Left bundle branch block Heart attacks (myocardial infarction) Thickened, stiffened or weakened ... myocarditis) High blood pressure (hypertension) Right bundle branch block A heart abnormality that's present at birth (congenital) — ...

  6. Polybenzimidazole block copolymers for fuel cell: synthesis and studies of block length effects on nanophase separation, mechanical properties, and proton conductivity of PEM.

    Science.gov (United States)

    Maity, Sudhangshu; Jana, Tushar

    2014-05-14

    A series of meta-polybenzimidazole-block-para-polybenzimidazole (m-PBI-b-p-PBI), segmented block copolymers of PBI, were synthesized with various structural motifs and block lengths by condensing the diamine terminated meta-PBI (m-PBI-Am) and acid terminated para-PBI (p-PBI-Ac) oligomers. NMR studies and existence of two distinct glass transition temperatures (Tg), obtained from dynamical mechanical analysis (DMA) results, unequivocally confirmed the formation of block copolymer structure through the current polymerization methodology. Appropriate and careful selection of oligomers chain length enabled us to tailor the block length of block copolymers and also to make varieties of structural motifs. Increasingly distinct Tg peaks with higher block length of segmented block structure attributed the decrease in phase mixing between the meta-PBI and para-PBI blocks, which in turn resulted into nanophase segregated domains. The proton conductivities of proton exchange membrane (PEM) developed from phosphoric acid (PA) doped block copolymer membranes were found to be increasing substantially with increasing block length of copolymers even though PA loading of these membranes did not alter appreciably with varying block length. For example when molecular weight (Mn) of blocks were increased from 1000 to 5500 then the proton conductivities at 160 °C of resulting copolymers increased from 0.05 to 0.11 S/cm. Higher block length induced nanophase separation between the blocks by creating less morphological barrier within the block which facilitated the movement of the proton in the block and hence resulting higher proton conductivity of the PEM. The structural varieties also influenced the phase separation and proton conductivity. In comparison to meta-para random copolymers reported earlier, the current meta-para segmented block copolymers were found to be more suitable for PBI-based PEM.

  7. Pancreas and cyst segmentation

    Science.gov (United States)

    Dmitriev, Konstantin; Gutenko, Ievgeniia; Nadeem, Saad; Kaufman, Arie

    2016-03-01

    Accurate segmentation of abdominal organs from medical images is an essential part of surgical planning and computer-aided disease diagnosis. Many existing algorithms are specialized for the segmentation of healthy organs. Cystic pancreas segmentation is especially challenging due to its low contrast boundaries, variability in shape, location and the stage of the pancreatic cancer. We present a semi-automatic segmentation algorithm for pancreata with cysts. In contrast to existing automatic segmentation approaches for healthy pancreas segmentation which are amenable to atlas/statistical shape approaches, a pancreas with cysts can have even higher variability with respect to the shape of the pancreas due to the size and shape of the cyst(s). Hence, fine results are better attained with semi-automatic steerable approaches. We use a novel combination of random walker and region growing approaches to delineate the boundaries of the pancreas and cysts with respective best Dice coefficients of 85.1% and 86.7%, and respective best volumetric overlap errors of 26.0% and 23.5%. Results show that the proposed algorithm for pancreas and pancreatic cyst segmentation is accurate and stable.

  8. Generalized Block Failure

    DEFF Research Database (Denmark)

    Jönsson, Jeppe

    2015-01-01

    Block tearing is considered in several codes as a pure block tension or a pure block shear failure mechanism. However in many situations the load acts eccentrically and involves the transfer of a substantial moment in combination with the shear force and perhaps a normal force. A literature study...... shows that no readily available tests with a well-defined substantial eccentricity have been performed. This paper presents theoretical and experimental work leading towards generalized block failure capacity methods. Simple combination of normal force, shear force and moment stress distributions along...... yield lines around the block leads to simple interaction formulas similar to other interaction formulas in the codes....

  9. Segmentation of consumer's markets and evaluation of market's segments

    OpenAIRE

    ŠVECOVÁ, Iveta

    2013-01-01

    The goal of this bachelor thesis was to explain a possibly segmentation of consumer´s markets for a chosen company, and to present a suitable goods offer, so it would be suitable to the needs of selected segments. The work is divided into theoretical and practical part. First part describes marketing, segmentation, segmentation of consumer's markets, consumer's market, market's segments a other terms. Second part describes an evaluation of questionnaire survey, discovering of market's segment...

  10. Segmental tuberculosis verrucosa cutis

    Directory of Open Access Journals (Sweden)

    Hanumanthappa H

    1994-01-01

    Full Text Available A case of segmental Tuberculosis Verrucosa Cutis is reported in 10 year old boy. The condition was resembling the ascending lymphangitic type of sporotrichosis. The lesions cleared on treatment with INH 150 mg daily for 6 months.

  11. Chromosome condensation and segmentation

    International Nuclear Information System (INIS)

    Viegas-Pequignot, E.M.

    1981-01-01

    Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs [fr

  12. International EUREKA: Initialization Segment

    International Nuclear Information System (INIS)

    1982-02-01

    The Initialization Segment creates the starting description of the uranium market. The starting description includes the international boundaries of trade, the geologic provinces, resources, reserves, production, uranium demand forecasts, and existing market transactions. The Initialization Segment is designed to accept information of various degrees of detail, depending on what is known about each region. It must transform this information into a specific data structure required by the Market Segment of the model, filling in gaps in the information through a predetermined sequence of defaults and built in assumptions. A principal function of the Initialization Segment is to create diagnostic messages indicating any inconsistencies in data and explaining which assumptions were used to organize the data base. This permits the user to manipulate the data base until such time the user is satisfied that all the assumptions used are reasonable and that any inconsistencies are resolved in a satisfactory manner

  13. Cache-Oblivious Red-Blue Line Segment Intersection

    DEFF Research Database (Denmark)

    Arge, Lars; Mølhave, Thomas; Zeh, Norbert

    2008-01-01

    We present an optimal cache-oblivious algorithm for finding all intersections between a set of non-intersecting red segments and a set of non-intersecting blue segments in the plane. Our algorithm uses $O(\\frac{N}{B}\\log_{M/B}\\frac{N}{B}+T/B)$ memory transfers, where N is the total number...... of segments, M and B are the memory and block transfer sizes of any two consecutive levels of any multilevel memory hierarchy, and T is the number of intersections....

  14. Thermal degradation of polymer systems having liquid crystalline oligoester segment

    Directory of Open Access Journals (Sweden)

    Renato Matroniani

    Full Text Available Abstract Block copolymers and blends comprised by liquid crystalline oligoester and polystyrene were prepared and their thermal stability were characterized by thermogravimetric analysis (TGA. The samples have shown three main decomposition temperatures due to (1 lost of flexible chain and decomposition of mesogenic segment, (2 decomposition of polystyrene and (3 final decomposition of oligoester rigid segment. Both copolymers and polymer blends presented lower thermal stability compared to polystyrene and oligoester. The residual mass after heating at 600 °C in copolymers and polymer blends were lower than those found in the oligoesters. A degradative process of aromatic segments of oligoester induced by decomposition of polystyrene is suggested.

  15. Segmentation in reading and film comprehension.

    Science.gov (United States)

    Zacks, Jeffrey M; Speer, Nicole K; Reynolds, Jeremy R

    2009-05-01

    When reading a story or watching a film, comprehenders construct a series of representations in order to understand the events depicted. Discourse comprehension theories and a recent theory of perceptual event segmentation both suggest that comprehenders monitor situational features such as characters' goals, to update these representations at natural boundaries in activity. However, the converging predictions of these theories had previously not been tested directly. Two studies provided evidence that changes in situational features such as characters, their locations, their interactions with objects, and their goals are related to the segmentation of events in both narrative texts and films. A 3rd study indicated that clauses with event boundaries are read more slowly than are other clauses and that changes in situational features partially mediate this relation. A final study suggested that the predictability of incoming information influences reading rate and possibly event segmentation. Taken together, these results suggest that processing situational changes during comprehension is an important determinant of how one segments ongoing activity into events and that this segmentation is related to the control of processing during reading. (c) 2009 APA, all rights reserved.

  16. Blocked Randomization with Randomly Selected Block Sizes

    Directory of Open Access Journals (Sweden)

    Jimmy Efird

    2010-12-01

    Full Text Available When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of individuals may be assigned to each arm of the study and thus decrease the power to detect statistically significant differences between groups. Block randomization is a commonly used technique in clinical trial design to reduce bias and achieve balance in the allocation of participants to treatment arms, especially when the sample size is small. This method increases the probability that each arm will contain an equal number of individuals by sequencing participant assignments by block. Yet still, the allocation process may be predictable, for example, when the investigator is not blind and the block size is fixed. This paper provides an overview of blocked randomization and illustrates how to avoid selection bias by using random block sizes.

  17. 31 CFR 595.301 - Blocked account; blocked property.

    Science.gov (United States)

    2010-07-01

    ... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY TERRORISM SANCTIONS REGULATIONS General Definitions § 595.301 Blocked account; blocked property. The terms blocked account and blocked...

  18. Block Copolymers: Synthesis and Applications in Nanotechnology

    Science.gov (United States)

    Lou, Qin

    This study is focused on the synthesis and study of (block) copolymers using reversible deactivation radical polymerizations (RDRPs), including atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. In particular, two primary areas of study are undertaken: (1) a proof-of-concept application of lithographic block copolymers, and (2) the mechanistic study of the deposition of titania into block copolymer templates for the production of well-ordered titania nanostructures. Block copolymers have the ability to undergo microphase separation, with an average size of each microphase ranging from tens to hundreds of nanometers. As such, block copolymers have been widely considered for nanotechnological applications over the past two decades. The development of materials for various nanotechnologies has become an increasingly studied area as improvements in many applications, such as those found in the semiconductor and photovoltaic industries are constantly being sought. Significant growth in developments of new synthetic methods ( i.e. RDRPs) has allowed the production of block copolymers with molecular (and sometimes atomic) definition. In turn, this has greatly expanded the use of block copolymers in nanotechnology. Herein, we describe the synthesis of statistical and block copolymers of 193 nm photolithography methacrylate and acrylate resist monomers with norbornyl and adamantyl moieties using RAFT polymerization.. For these resist (block) copolymers, the phase separation behaviors were examined by atomic force microscopy (AFM). End groups were removed from the polymers to avoid complications during the photolithography since RAFT end groups absorb visible light. Poly(glycidyl methacrylate-block-polystyrene) (PGMA-b-PS) was synthesize by ATRP and demonstrated that this block copolymer acts as both a lithographic UV (365 nm) photoresist and a self-assembly material. The PGMA segments can undergo cationic

  19. Fluence map segmentation

    International Nuclear Information System (INIS)

    Rosenwald, J.-C.

    2008-01-01

    The lecture addressed the following topics: 'Interpreting' the fluence map; The sequencer; Reasons for difference between desired and actual fluence map; Principle of 'Step and Shoot' segmentation; Large number of solutions for given fluence map; Optimizing 'step and shoot' segmentation; The interdigitation constraint; Main algorithms; Conclusions on segmentation algorithms (static mode); Optimizing intensity levels and monitor units; Sliding window sequencing; Synchronization to avoid the tongue-and-groove effect; Accounting for physical characteristics of MLC; Importance of corrections for leaf transmission and offset; Accounting for MLC mechanical constraints; The 'complexity' factor; Incorporating the sequencing into optimization algorithm; Data transfer to the treatment machine; Interface between R and V and accelerator; and Conclusions on fluence map segmentation (Segmentation is part of the overall inverse planning procedure; 'Step and Shoot' and 'Dynamic' options are available for most TPS (depending on accelerator model; The segmentation phase tends to come into the optimization loop; The physical characteristics of the MLC have a large influence on final dose distribution; The IMRT plans (MU and relative dose distribution) must be carefully validated). (P.A.)

  20. Gamifying Video Object Segmentation.

    Science.gov (United States)

    Spampinato, Concetto; Palazzo, Simone; Giordano, Daniela

    2017-10-01

    Video object segmentation can be considered as one of the most challenging computer vision problems. Indeed, so far, no existing solution is able to effectively deal with the peculiarities of real-world videos, especially in cases of articulated motion and object occlusions; limitations that appear more evident when we compare the performance of automated methods with the human one. However, manually segmenting objects in videos is largely impractical as it requires a lot of time and concentration. To address this problem, in this paper we propose an interactive video object segmentation method, which exploits, on one hand, the capability of humans to identify correctly objects in visual scenes, and on the other hand, the collective human brainpower to solve challenging and large-scale tasks. In particular, our method relies on a game with a purpose to collect human inputs on object locations, followed by an accurate segmentation phase achieved by optimizing an energy function encoding spatial and temporal constraints between object regions as well as human-provided location priors. Performance analysis carried out on complex video benchmarks, and exploiting data provided by over 60 users, demonstrated that our method shows a better trade-off between annotation times and segmentation accuracy than interactive video annotation and automated video object segmentation approaches.

  1. Strategic market segmentation

    Directory of Open Access Journals (Sweden)

    Maričić Branko R.

    2015-01-01

    Full Text Available Strategic planning of marketing activities is the basis of business success in modern business environment. Customers are not homogenous in their preferences and expectations. Formulating an adequate marketing strategy, focused on realization of company's strategic objectives, requires segmented approach to the market that appreciates differences in expectations and preferences of customers. One of significant activities in strategic planning of marketing activities is market segmentation. Strategic planning imposes a need to plan marketing activities according to strategically important segments on the long term basis. At the same time, there is a need to revise and adapt marketing activities on the short term basis. There are number of criteria based on which market segmentation is performed. The paper will consider effectiveness and efficiency of different market segmentation criteria based on empirical research of customer expectations and preferences. The analysis will include traditional criteria and criteria based on behavioral model. The research implications will be analyzed from the perspective of selection of the most adequate market segmentation criteria in strategic planning of marketing activities.

  2. Preparation and development of block copolypeptide vesicles and hydrogels for biological and medical applications

    OpenAIRE

    Deming, TJ

    2014-01-01

    There have been many recent advances in the controlled polymerization of α-amino acid-N-carboxyanhydride (NCA) monomers into well-defined block copolypeptides. Transition metal initiating systems allow block copolypeptide synthesis with excellent control over number and lengths of block segments, chain length distribution, and chain-end functionality. Using this and other methods, block copolypeptides of controlled dimensions have been prepared and their self-assembly into organized structure...

  3. Inferior vena cava segmentation with parameter propagation and graph cut.

    Science.gov (United States)

    Yan, Zixu; Chen, Feng; Wu, Fa; Kong, Dexing

    2017-09-01

    The inferior vena cava (IVC) is one of the vital veins inside the human body. Accurate segmentation of the IVC from contrast-enhanced CT images is of great importance. This extraction not only helps the physician understand its quantitative features such as blood flow and volume, but also it is helpful during the hepatic preoperative planning. However, manual delineation of the IVC is time-consuming and poorly reproducible. In this paper, we propose a novel method to segment the IVC with minimal user interaction. The proposed method performs the segmentation block by block between user-specified beginning and end masks. At each stage, the proposed method builds the segmentation model based on information from image regional appearances, image boundaries, and a prior shape. The intensity range and the prior shape for this segmentation model are estimated based on the segmentation result from the last block, or from user- specified beginning mask if at first stage. Then, the proposed method minimizes the energy function and generates the segmentation result for current block using graph cut. Finally, a backward tracking step from the end of the IVC is performed if necessary. We have tested our method on 20 clinical datasets and compared our method to three other vessel extraction approaches. The evaluation was performed using three quantitative metrics: the Dice coefficient (Dice), the mean symmetric distance (MSD), and the Hausdorff distance (MaxD). The proposed method has achieved a Dice of [Formula: see text], an MSD of [Formula: see text] mm, and a MaxD of [Formula: see text] mm, respectively, in our experiments. The proposed approach can achieve a sound performance with a relatively low computational cost and a minimal user interaction. The proposed algorithm has high potential to be applied for the clinical applications in the future.

  4. Block Cipher Analysis

    DEFF Research Database (Denmark)

    Miolane, Charlotte Vikkelsø

    ensurethat no attack violatesthe securitybounds specifiedbygeneric attack namely exhaustivekey search and table lookup attacks. This thesis contains a general introduction to cryptography with focus on block ciphers and important block cipher designs, in particular the Advanced Encryption Standard(AES...... on small scale variants of AES. In the final part of the thesis we present a new block cipher proposal Present and examine its security against algebraic and differential cryptanalysis in particular....

  5. Rediscovering market segmentation.

    Science.gov (United States)

    Yankelovich, Daniel; Meer, David

    2006-02-01

    In 1964, Daniel Yankelovich introduced in the pages of HBR the concept of nondemographic segmentation, by which he meant the classification of consumers according to criteria other than age, residence, income, and such. The predictive power of marketing studies based on demographics was no longer strong enough to serve as a basis for marketing strategy, he argued. Buying patterns had become far better guides to consumers' future purchases. In addition, properly constructed nondemographic segmentations could help companies determine which products to develop, which distribution channels to sell them in, how much to charge for them, and how to advertise them. But more than 40 years later, nondemographic segmentation has become just as unenlightening as demographic segmentation had been. Today, the technique is used almost exclusively to fulfill the needs of advertising, which it serves mainly by populating commercials with characters that viewers can identify with. It is true that psychographic types like "High-Tech Harry" and "Joe Six-Pack" may capture some truth about real people's lifestyles, attitudes, self-image, and aspirations. But they are no better than demographics at predicting purchase behavior. Thus they give corporate decision makers very little idea of how to keep customers or capture new ones. Now, Daniel Yankelovich returns to these pages, with consultant David Meer, to argue the case for a broad view of nondemographic segmentation. They describe the elements of a smart segmentation strategy, explaining how segmentations meant to strengthen brand identity differ from those capable of telling a company which markets it should enter and what goods to make. And they introduce their "gravity of decision spectrum", a tool that focuses on the form of consumer behavior that should be of the greatest interest to marketers--the importance that consumers place on a product or product category.

  6. Quantum partial search for uneven distribution of multiple target items

    Science.gov (United States)

    Zhang, Kun; Korepin, Vladimir

    2018-06-01

    Quantum partial search algorithm is an approximate search. It aims to find a target block (which has the target items). It runs a little faster than full Grover search. In this paper, we consider quantum partial search algorithm for multiple target items unevenly distributed in a database (target blocks have different number of target items). The algorithm we describe can locate one of the target blocks. Efficiency of the algorithm is measured by number of queries to the oracle. We optimize the algorithm in order to improve efficiency. By perturbation method, we find that the algorithm runs the fastest when target items are evenly distributed in database.

  7. Partial tooth gear bearings

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  8. Scorpion image segmentation system

    Science.gov (United States)

    Joseph, E.; Aibinu, A. M.; Sadiq, B. A.; Bello Salau, H.; Salami, M. J. E.

    2013-12-01

    Death as a result of scorpion sting has been a major public health problem in developing countries. Despite the high rate of death as a result of scorpion sting, little report exists in literature of intelligent device and system for automatic detection of scorpion. This paper proposed a digital image processing approach based on the floresencing characteristics of Scorpion under Ultra-violet (UV) light for automatic detection and identification of scorpion. The acquired UV-based images undergo pre-processing to equalize uneven illumination and colour space channel separation. The extracted channels are then segmented into two non-overlapping classes. It has been observed that simple thresholding of the green channel of the acquired RGB UV-based image is sufficient for segmenting Scorpion from other background components in the acquired image. Two approaches to image segmentation have also been proposed in this work, namely, the simple average segmentation technique and K-means image segmentation. The proposed algorithm has been tested on over 40 UV scorpion images obtained from different part of the world and results obtained show an average accuracy of 97.7% in correctly classifying the pixel into two non-overlapping clusters. The proposed 1system will eliminate the problem associated with some of the existing manual approaches presently in use for scorpion detection.

  9. Essays on partial retirement

    NARCIS (Netherlands)

    Kantarci, T.

    2012-01-01

    The five essays in this dissertation address a range of topics in the micro-economic literature on partial retirement. The focus is on the labor market behavior of older age groups. The essays examine the economic and non-economic determinants of partial retirement behavior, the effect of partial

  10. Optimal Goodwill Model with Consumer Recommendations and Market Segmentation

    OpenAIRE

    Bogusz, Dominika; Górajski, Mariusz

    2014-01-01

    We propose a new dynamic model of product goodwill where a product is sold in many market segments, and where the segments are indicated by the usage experience of consumers. The dynamics of product goodwill is described by a partial differential equation of the Lotka–Sharpe– McKendrick type. The main novelty of this model is that the product goodwill in a segment of new consumers depends not only on advertising effort, but also on consumer recommendations, for which we introduce a mathematic...

  11. Intradomain Textures in Block Copolymers: Multizone Alignment and Biaxiality

    Science.gov (United States)

    Prasad, Ishan; Seo, Youngmi; Hall, Lisa M.; Grason, Gregory M.

    2017-06-01

    Block copolymer (BCP) melt assembly has been studied for decades, focusing largely on self-organized spatial patterns of periodically ordered segment density. Here, we demonstrate that underlying the well-known composition profiles (i.e., ordered lamella, cylinders, spheres, and networks) are generic and heterogeneous patterns of segment orientation that couple strongly to morphology, even in the absence of specific factors that promote intra or interchain segment alignment. We employ both self-consistent field theory and coarse-grained simulation methods to measure polar and nematic order parameters of segments in a freely jointed chain model of diblock melts. We show that BCP morphologies have a multizone texture, with segments predominantly aligned normal and parallel to interdomain interfaces in the respective brush and interfacial regions of the microdomain. Further, morphologies with anisotropically curved interfaces (i.e., cylinders and networks) exhibit biaxial order that is aligned to the principal curvature axes of the interface.

  12. Related Drupal Nodes Block

    NARCIS (Netherlands)

    Van der Vegt, Wim

    2010-01-01

    Related Drupal Nodes Block This module exposes a block that uses Latent Semantic Analysis (Lsa) internally to suggest three nodes that are relevant to the node a user is viewing. This module performs three tasks. 1) It periodically indexes a Drupal site and generates a Lsa Term Document Matrix.

  13. Designers Block 2002

    DEFF Research Database (Denmark)

    Dickson, Thomas

    2002-01-01

    Artiklen indleder med: ved siden aaf Londons etablerede designmesse '100% Design', er der vokset et undergrundsmiljø af designudstillinger op. Det dominerende og mest kendte initiativ er Designers Block, der i år udstillede to steder i byen. Designers Block er et mere uformelt udstillingsforum...

  14. Connecting textual segments

    DEFF Research Database (Denmark)

    Brügger, Niels

    2017-01-01

    history than just the years of the emergence of the web, the chapter traces the history of how segments of text have deliberately been connected to each other by the use of specific textual and media features, from clay tablets, manuscripts on parchment, and print, among others, to hyperlinks on stand......In “Connecting textual segments: A brief history of the web hyperlink” Niels Brügger investigates the history of one of the most fundamental features of the web: the hyperlink. Based on the argument that the web hyperlink is best understood if it is seen as another step in a much longer and broader...

  15. Recurrent Partial Words

    Directory of Open Access Journals (Sweden)

    Francine Blanchet-Sadri

    2011-08-01

    Full Text Available Partial words are sequences over a finite alphabet that may contain wildcard symbols, called holes, which match or are compatible with all letters; partial words without holes are said to be full words (or simply words. Given an infinite partial word w, the number of distinct full words over the alphabet that are compatible with factors of w of length n, called subwords of w, refers to a measure of complexity of infinite partial words so-called subword complexity. This measure is of particular interest because we can construct partial words with subword complexities not achievable by full words. In this paper, we consider the notion of recurrence over infinite partial words, that is, we study whether all of the finite subwords of a given infinite partial word appear infinitely often, and we establish connections between subword complexity and recurrence in this more general framework.

  16. Multichannel conformal blocks for scattering amplitudes

    Science.gov (United States)

    Belitsky, A. V.

    2018-05-01

    By performing resummation of small fermion-antifermion pairs within the pentagon form factor program to scattering amplitudes in planar N = 4 superYang-Mills theory, we construct multichannel conformal blocks within the flux-tube picture for N-sided NMHV polygons. This procedure is equivalent to summation of descendants of conformal primaries in the OPE framework. The resulting conformal partial waves are determined by multivariable hypergeometric series of Lauricella-Saran type.

  17. Segmentation in cinema perception.

    Science.gov (United States)

    Carroll, J M; Bever, T G

    1976-03-12

    Viewers perceptually segment moving picture sequences into their cinematically defined units: excerpts that follow short film sequences are recognized faster when the excerpt originally came after a structural cinematic break (a cut or change in the action) than when it originally came before the break.

  18. Dictionary Based Image Segmentation

    DEFF Research Database (Denmark)

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2015-01-01

    We propose a method for weakly supervised segmentation of natural images, which may contain both textured or non-textured regions. Our texture representation is based on a dictionary of image patches. To divide an image into separated regions with similar texture we use an implicit level sets...

  19. Unsupervised Image Segmentation

    Czech Academy of Sciences Publication Activity Database

    Haindl, Michal; Mikeš, Stanislav

    2014-01-01

    Roč. 36, č. 4 (2014), s. 23-23 R&D Projects: GA ČR(CZ) GA14-10911S Institutional support: RVO:67985556 Keywords : unsupervised image segmentation Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/2014/RO/haindl-0434412.pdf

  20. Metrics for image segmentation

    Science.gov (United States)

    Rees, Gareth; Greenway, Phil; Morray, Denise

    1998-07-01

    An important challenge in mapping image-processing techniques onto applications is the lack of quantitative performance measures. From a systems engineering perspective these are essential if system level requirements are to be decomposed into sub-system requirements which can be understood in terms of algorithm selection and performance optimization. Nowhere in computer vision is this more evident than in the area of image segmentation. This is a vigorous and innovative research activity, but even after nearly two decades of progress, it remains almost impossible to answer the question 'what would the performance of this segmentation algorithm be under these new conditions?' To begin to address this shortcoming, we have devised a well-principled metric for assessing the relative performance of two segmentation algorithms. This allows meaningful objective comparisons to be made between their outputs. It also estimates the absolute performance of an algorithm given ground truth. Our approach is an information theoretic one. In this paper, we describe the theory and motivation of our method, and present practical results obtained from a range of state of the art segmentation methods. We demonstrate that it is possible to measure the objective performance of these algorithms, and to use the information so gained to provide clues about how their performance might be improved.

  1. Predictability of blocking

    International Nuclear Information System (INIS)

    Tosi, E.; Ruti, P.; Tibaldi, S.; D'Andrea, F.

    1994-01-01

    Tibaldi and Molteni (1990, hereafter referred to as TM) had previously investigated operational blocking predictability by the ECMWF model and the possible relationships between model systematic error and blocking in the winter season of the Northern Hemisphere, using seven years of ECMWF operational archives of analyses and day 1 to 10 forecasts. They showed that fewer blocking episodes than in the real atmosphere were generally simulated by the model, and that this deficiency increased with increasing forecast time. As a consequence of this, a major contribution to the systematic error in the winter season was shown to derive from the inability of the model to properly forecast blocking. In this study, the analysis performed in TM for the first seven winter seasons of the ECMWF operational model is extended to the subsequent five winters, during which model development, reflecting both resolution increases and parametrisation modifications, continued unabated. In addition the objective blocking index developed by TM has been applied to the observed data to study the natural low frequency variability of blocking. The ability to simulate blocking of some climate models has also been tested

  2. 47 CFR 52.20 - Thousands-block number pooling.

    Science.gov (United States)

    2010-10-01

    ... aligned with any particular telecommunication industry segment, and shall comply with the same neutrality... 47 Telecommunication 3 2010-10-01 2010-10-01 false Thousands-block number pooling. 52.20 Section 52.20 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES...

  3. Gas-permeation properties of poly(ethylene oxide) poly(butylene terephthalate block copolymers

    NARCIS (Netherlands)

    Metz, S.J.; Mulder, M.H.V.; Wessling, Matthias

    2004-01-01

    This paper reports the gas-permeation properties of poly(ethylene oxide) (PEO) poly(butylene terephthalate) (PBT) segmented multiblock copolymers. These block copolymers allow a precise structural modification by the amount of PBT and the PEO segment length, enabling a systematic study of the

  4. 31 CFR 594.301 - Blocked account; blocked property.

    Science.gov (United States)

    2010-07-01

    ... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY GLOBAL TERRORISM SANCTIONS REGULATIONS General Definitions § 594.301 Blocked account; blocked property. The terms blocked account and...

  5. RX for Writer's Block.

    Science.gov (United States)

    Tompkins, Gail E.; Camp, Donna J.

    1988-01-01

    Describes four prewriting techniques that elementary and middle grade students can use to gather and organize ideas for writing, and by so doing, cure writer's block. Techniques discussed are: (1) brainstorming; (2) clustering; (3) freewriting; and (4) cubing.

  6. Block copolymer battery separator

    Science.gov (United States)

    Wong, David; Balsara, Nitash Pervez

    2016-04-26

    The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.

  7. Blocking in Category Learning

    OpenAIRE

    Bott, Lewis; Hoffman, Aaron B.; Murphy, Gregory L.

    2007-01-01

    Many theories of category learning assume that learning is driven by a need to minimize classification error. When there is no classification error, therefore, learning of individual features should be negligible. We tested this hypothesis by conducting three category learning experiments adapted from an associative learning blocking paradigm. Contrary to an error-driven account of learning, participants learned a wide range of information when they learned about categories, and blocking effe...

  8. Genetic determinants of P wave duration and PR segment

    NARCIS (Netherlands)

    Verweij, Niek; Mateo Leach, Irene; van den Boogaard, Malou; van Veldhuisen, Dirk J.; Christoffels, Vincent M.; Hillege, Hans L.; van Gilst, Wiek H.; Barnett, Phil; de Boer, Rudolf A.; van der Harst, Pim

    2014-01-01

    The PR interval on the ECG reflects atrial depolarization and atrioventricular nodal delay which can be partially differentiated by P wave duration and PR segment, respectively. Genome-wide association studies have identified several genetic loci for PR interval, but it remains to be determined

  9. Genetic Determinants of P Wave Duration and PR Segment

    NARCIS (Netherlands)

    Verweij, Niek; Mateo Leach, Irene; van den Boogaard, Malou; van Veldhuisen, Dirk J.; Christoffels, Vincent M.; Hillege, Hans L.; van Gilst, Wiek H.; Barnett, Phil; de Boer, Rudolf A.; van der Harst, Pim

    Background-The PR interval on the ECG reflects atrial depolarization and atrioventricular nodal delay which can be partially differentiated by P wave duration and PR segment, respectively. Genome-wide association studies have identified several genetic loci for PR interval, but it remains to be

  10. Scintillation counter, segmented shield

    International Nuclear Information System (INIS)

    Olson, R.E.; Thumim, A.D.

    1975-01-01

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into radiation-responsive areas. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (U.S.)

  11. Head segmentation in vertebrates

    OpenAIRE

    Kuratani, Shigeru; Schilling, Thomas

    2008-01-01

    Classic theories of vertebrate head segmentation clearly exemplify the idealistic nature of comparative embryology prior to the 20th century. Comparative embryology aimed at recognizing the basic, primary structure that is shared by all vertebrates, either as an archetype or an ancestral developmental pattern. Modern evolutionary developmental (Evo-Devo) studies are also based on comparison, and therefore have a tendency to reduce complex embryonic anatomy into overly simplified patterns. Her...

  12. Video segmentation using keywords

    Science.gov (United States)

    Ton-That, Vinh; Vong, Chi-Tai; Nguyen-Dao, Xuan-Truong; Tran, Minh-Triet

    2018-04-01

    At DAVIS-2016 Challenge, many state-of-art video segmentation methods achieve potential results, but they still much depend on annotated frames to distinguish between background and foreground. It takes a lot of time and efforts to create these frames exactly. In this paper, we introduce a method to segment objects from video based on keywords given by user. First, we use a real-time object detection system - YOLOv2 to identify regions containing objects that have labels match with the given keywords in the first frame. Then, for each region identified from the previous step, we use Pyramid Scene Parsing Network to assign each pixel as foreground or background. These frames can be used as input frames for Object Flow algorithm to perform segmentation on entire video. We conduct experiments on a subset of DAVIS-2016 dataset in half the size of its original size, which shows that our method can handle many popular classes in PASCAL VOC 2012 dataset with acceptable accuracy, about 75.03%. We suggest widely testing by combining other methods to improve this result in the future.

  13. Market segmentation in behavioral perspective.

    OpenAIRE

    Wells, V.K.; Chang, S.W.; Oliveira-Castro, J.M.; Pallister, J.

    2010-01-01

    A segmentation approach is presented using both traditional demographic segmentation bases (age, social class/occupation, and working status) and a segmentation by benefits sought. The benefits sought in this case are utilitarian and informational reinforcement, variables developed from the Behavioral Perspective Model (BPM). Using data from 1,847 consumers and from a total of 76,682 individual purchases, brand choice and price and reinforcement responsiveness were assessed for each segment a...

  14. Shape-Tailored Features and their Application to Texture Segmentation

    KAUST Repository

    Khan, Naeemullah

    2014-04-01

    Texture Segmentation is one of the most challenging areas of computer vision. One reason for this difficulty is the huge variety and variability of textures occurring in real world, making it very difficult to quantitatively study textures. One of the key tools used for texture segmentation is local invariant descriptors. Texture consists of textons, the basic building block of textures, that may vary by small nuisances like illumination variation, deformations, and noise. Local invariant descriptors are robust to these nuisances making them beneficial for texture segmentation. However, grouping dense descriptors directly for segmentation presents a problem: existing descriptors aggregate data from neighborhoods that may contain different textured regions, making descriptors from these neighborhoods difficult to group, leading to significant errors in segmentation. This work addresses this issue by proposing dense local descriptors, called Shape-Tailored Features, which are tailored to an arbitrarily shaped region, aggregating data only within the region of interest. Since the segmentation, i.e., the regions, are not known a-priori, we propose a joint problem for Shape-Tailored Features and the regions. We present a framework based on variational methods. Extensive experiments on a new large texture dataset, which we introduce, show that the joint approach with Shape-Tailored Features leads to better segmentations over the non-joint non Shape-Tailored approach, and the method out-performs existing state-of-the-art.

  15. Síntese e caracterização de poliuretanos segmentados contendo blocos de peso molecular controlado: parte 1 preparação e caracterização dos materiais Synthesis and characterization of segmented polyurethanes containing blocks of controlled molecular weight: 1. Materials preparation and characterization

    Directory of Open Access Journals (Sweden)

    C. L. Almeida

    1999-06-01

    Full Text Available Um novo método de síntese de poliuretanos segmentados foi desenvolvido, no qual segmentos de características bem definidas foram preparados separadamente e acoplados em uma etapa seguinte. O segmento flexível (SS foi preparado a partir da reação entre glicol polipropilênico comercial de peso molecular 3800 e diisocianato de 1,6 hexametileno (HDI. O peso molecular destes blocos variou de acordo com a razão NCO/OH usada nas sínteses, que foi sempre maior do que a unidade, fornecendo blocos com terminação NCO. O HDI não reagido foi removido à vácuo (10-6-10-8mbar. O peso molecular dos produtos SS foi determinado por GPC. O segmento rígido (HS foi preparado a partir da reação de HDI e 1,4 butanodiol (BDO usando-se razão NCO/OH igual à unidade. Ao término desta reação os produtos foram funcionalizados pela adição de um excesso de BDO, fornecendo segmentos com terminação -OH. O BDO não reagido foi removido por extração com solvente. O peso molecular dos produtos correspondentes aos segmentos HS foi determinado através da técnica de dessorção à laser (MALDI - Matrix Assisted Laser Desorption. O acoplamento dos segmentos flexíveis com os rígidos fornecendo os produtos SPU foi feito em solução de DMF. Um poliuretano convencional foi preparado pela técnica em duas etapas (produto PU para comparação de efeitos estrutura-propriedades. A espectroscopia no infravermelho foi usada com o intuito de se observar diferenças em interações intermoleculares referentes aos produtos PU e SPU, mas estas diferenças só foram acessíveis através de estudos morfológicos que serão publicados em continuação a este estudo.A new method for segmented polyurethanes synthesis (SPU was developed, in which segments of well-defined characteristics were prepared separately and coupled together in a further step. The soft segment was prepared from the reaction of commercially available anionic polyol-polyether, with an average

  16. Self-sorting of guests and hard blocks in bisurea-based thermoplastic elastomers

    NARCIS (Netherlands)

    Botterhuis, N.E.; Karthikeyan, S.; Spiering, A.J.H.; Sijbesma, R.P.

    2010-01-01

    Self-sorting in thermoplastic elastomers was studied using bisurea-based thermoplastic elastomers (TPEs) which are known to form hard blocks via hierarchical aggregation of bisurea segments into ribbons and of ribbons into fibers. Self-sorting of different bisurea hard blocks in mixtures of polymers

  17. Synthesis and properties of lyotropic poly(amide-block-aramid) copolymers

    NARCIS (Netherlands)

    De Ruijter, C.

    2006-01-01

    This thesis describes the synthesis and properties of liquid crystalline block copolymers comprised of alternating rigid and flexible blocks for the preparation of self-reinforcing materials. The incentive for this work was the expectation that the rigid segments would phase separate on a

  18. Multi-block sulfonated poly(phenylene) copolymer proton exchange membranes

    Science.gov (United States)

    Fujimoto, Cy H [Albuquerque, NM; Hibbs, Michael [Albuquerque, NM; Ambrosini, Andrea [Albuquerque, NM

    2012-02-07

    Improved multi-block sulfonated poly(phenylene) copolymer compositions, methods of making the same, and their use as proton exchange membranes (PEM) in hydrogen fuel cells, direct methanol fuel cells, in electrode casting solutions and electrodes. The multi-block architecture has defined, controllable hydrophobic and hydrophilic segments. These improved membranes have better ion transport (proton conductivity) and water swelling properties.

  19. Segmenting the Adult Education Market.

    Science.gov (United States)

    Aurand, Tim

    1994-01-01

    Describes market segmentation and how the principles of segmentation can be applied to the adult education market. Indicates that applying segmentation techniques to adult education programs results in programs that are educationally and financially satisfying and serve an appropriate population. (JOW)

  20. Market Segmentation for Information Services.

    Science.gov (United States)

    Halperin, Michael

    1981-01-01

    Discusses the advantages and limitations of market segmentation as strategy for the marketing of information services made available by nonprofit organizations, particularly libraries. Market segmentation is defined, a market grid for libraries is described, and the segmentation of information services is outlined. A 16-item reference list is…

  1. Right bundle branch block and anterior wall ST elevation myocardial infarction.

    Science.gov (United States)

    Trofin, Monica; Israel, Carsten W; Barold, S Serge

    2017-09-01

    We report the case of an acute anterior wall ST elevation myocardial infarction with new left anterior fascicular block and pre-existing right bundle branch block. Due to a wide right bundle branch block, no ST segment elevation was visible in lead V1. The left anterior fascicular block was caused by proximal occlusion of the left artery descending and disappeared after acute revascularization. However, also the R' of the right bundle branch block became significantly shorter after revascularization, dismanteling a minor ST segment elevation. The ST elevation in lead V1 in anterior wall infarction and right bundle branch block may merge with the R' and cause a further QRS widening as an "equivalent" to the ST elevation.

  2. Uniaxial backfill block compaction

    International Nuclear Information System (INIS)

    Koskinen, V.

    2012-05-01

    The main parts of the project were: to make a literature survey of the previous uniaxial compaction experiments; do uniaxial compaction tests in laboratory scale; and do industrial scale production tests. Object of the project was to sort out the different factors affecting the quality assurance chain of the backfill block uniaxial production and solve a material sticking to mould problem which appeared during manufacturing the blocks of bentonite and cruched rock mixture. The effect of mineralogical and chemical composition on the long term functionality of the backfill was excluded from the project. However, the used smectite-rich clays have been tested for mineralogical consistency. These tests were done in B and Tech OY according their SOPs. The objective of the Laboratory scale tests was to find right material- and compaction parameters for the industrial scale tests. Direct comparison between the laboratory scale tests and industrial scale tests is not possible because the mould geometry and compaction speed has a big influence for the compaction process. For this reason the selected material parameters were also affected by the previous compaction experiments. The industrial scale tests were done in summer of 2010 in southern Sweden. Blocks were done with uniaxial compaction. A 40 tons of the mixture of bentonite and crushed rock blocks and almost 50 tons of Friedland-clay blocks were compacted. (orig.)

  3. Impression block with orientator

    International Nuclear Information System (INIS)

    Brilin, V I; Ulyanova, O S

    2015-01-01

    Tool review, namely the impression block, applied to check the shape and size of the top of fish as well as to determine the appropriate tool for fishing operation was realized. For multiple application and obtaining of the impress depth of 3 cm and more, the standard volumetric impression blocks with fix rods are used. However, the registered impress of fish is not oriented in space and the rods during fishing are in the extended position. This leads to rods deformation and sinking due to accidental impacts of impression block over the borehole irregularity and finally results in faulty detection of the top end of fishing object in hole. The impression blocks with copy rods and fixed magnetic needle allow estimating the object configuration and fix the position of magnetic needle determining the position of the top end of object in hole. However, the magnetic needle fixation is realized in staged and the rods are in extended position during fishing operations as well as it is in standard design. The most efficient tool is the impression block with copy rods which directs the examined object in the borehole during readings of magnetic needles data from azimuth plate and averaging of readings. This significantly increases the accuracy of fishing toll direction. The rods during fishing are located in the body and extended only when they reach the top of fishing object

  4. Electrorheological Properties of Suspensions Prepared from Polystyrene- Block- Polyisoprene Copolymer

    OpenAIRE

    YAVUZ, Mustafa

    2014-01-01

    Considerable scientific and industrial interest is currently being focused on a class of materials known as electrorheological (ER) fluids, which display remarkable rheological behaviour, being able to convert rapidly and repeatedly from a liquid to solid when an electric field (E) is applied or removed. In this article, the synthesis, characterization, partial hydrolysis and ER properties of polystyrene- block}-polyisoprene copolymer (COP) were investigated. The block copolymer was ...

  5. Integral-fuel blocks

    International Nuclear Information System (INIS)

    Cunningham, C.; Simpkin, S.D.

    1975-01-01

    A prismatic moderator block is described which has fuel-containing channels and coolant channels disposed parallel to each other and to edge faces of the block. The coolant channels are arranged in rows on an equilateral triangular lattice pattern and the fuel-containing channels are disposed in a regular lattice pattern with one fuel-containing channel between and equidistant from each of the coolant channels in each group of three mutually adjacent coolant channels. The edge faces of the block are parallel to the rows of coolant channels and the channels nearest to each edge face are disposed in two rows parallel thereto, with one of the rows containing only coolant channels and the other row containing only fuel-containing channels. (Official Gazette)

  6. Right bundle branch block

    DEFF Research Database (Denmark)

    Bussink, Barbara E; Holst, Anders Gaarsdal; Jespersen, Lasse

    2013-01-01

    AimsTo determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population.Methods and resultsWe followed 18 441 participants included...... in the Copenhagen City Heart Study examined in 1976-2003 free from previous myocardial infarction (MI), chronic heart failure, and left bundle branch block through registry linkage until 2009 for all-cause mortality and cardiovascular outcomes. The prevalence of RBBB/IRBBB was higher in men (1.4%/4.7% in men vs. 0.......5%/2.3% in women, P block was associated with significantly...

  7. Albedo estimation for scene segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C H; Rosenfeld, A

    1983-03-01

    Standard methods of image segmentation do not take into account the three-dimensional nature of the underlying scene. For example, histogram-based segmentation tacitly assumes that the image intensity is piecewise constant, and this is not true when the scene contains curved surfaces. This paper introduces a method of taking 3d information into account in the segmentation process. The image intensities are adjusted to compensate for the effects of estimated surface orientation; the adjusted intensities can be regarded as reflectivity estimates. When histogram-based segmentation is applied to these new values, the image is segmented into parts corresponding to surfaces of constant reflectivity in the scene. 7 references.

  8. ["Habitual" left branch block alternating with 2 "disguised" bracnch block].

    Science.gov (United States)

    Lévy, S; Jullien, G; Mathieu, P; Mostefa, S; Gérard, R

    1976-10-01

    Two cases of alternating left bundle branch block and "masquerading block" (with left bundle branch morphology in the stnadard leads and right bundle branch block morphology in the precordial leads) were studied by serial tracings and his bundle electrocardiography. In case 1 "the masquerading" block was associated with a first degree AV block related to a prolongation of HV interval. This case is to our knowledge the first cas of alternating bundle branch block in which his bundle activity was recorded in man. In case 2, the patient had atrial fibrilation and His bundle recordings were performed while differents degrees of left bundle branch block were present: The mechanism of the alternation and the concept of "masquerading" block are discussed. It is suggested that this type of block represents a right bundle branch block associated with severe lesions of the "left system".

  9. Hyperbolic partial differential equations

    CERN Document Server

    Witten, Matthew

    1986-01-01

    Hyperbolic Partial Differential Equations III is a refereed journal issue that explores the applications, theory, and/or applied methods related to hyperbolic partial differential equations, or problems arising out of hyperbolic partial differential equations, in any area of research. This journal issue is interested in all types of articles in terms of review, mini-monograph, standard study, or short communication. Some studies presented in this journal include discretization of ideal fluid dynamics in the Eulerian representation; a Riemann problem in gas dynamics with bifurcation; periodic M

  10. Successful removable partial dentures.

    Science.gov (United States)

    Lynch, Christopher D

    2012-03-01

    Removable partial dentures (RPDs) remain a mainstay of prosthodontic care for partially dentate patients. Appropriately designed, they can restore masticatory efficiency, improve aesthetics and speech, and help secure overall oral health. However, challenges remain in providing such treatments, including maintaining adequate plaque control, achieving adequate retention, and facilitating patient tolerance. The aim of this paper is to review the successful provision of RPDs. Removable partial dentures are a successful form of treatment for replacing missing teeth, and can be successfully provided with appropriate design and fabrication concepts in mind.

  11. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2011-01-01

    A rigorous, yet accessible, introduction to partial differential equations-updated in a valuable new edition Beginning Partial Differential Equations, Second Edition provides a comprehensive introduction to partial differential equations (PDEs) with a special focus on the significance of characteristics, solutions by Fourier series, integrals and transforms, properties and physical interpretations of solutions, and a transition to the modern function space approach to PDEs. With its breadth of coverage, this new edition continues to present a broad introduction to the field, while also addres

  12. FRAMEWORK FOR COMPARING SEGMENTATION ALGORITHMS

    Directory of Open Access Journals (Sweden)

    G. Sithole

    2015-05-01

    Full Text Available The notion of a ‘Best’ segmentation does not exist. A segmentation algorithm is chosen based on the features it yields, the properties of the segments (point sets it generates, and the complexity of its algorithm. The segmentation is then assessed based on a variety of metrics such as homogeneity, heterogeneity, fragmentation, etc. Even after an algorithm is chosen its performance is still uncertain because the landscape/scenarios represented in a point cloud have a strong influence on the eventual segmentation. Thus selecting an appropriate segmentation algorithm is a process of trial and error. Automating the selection of segmentation algorithms and their parameters first requires methods to evaluate segmentations. Three common approaches for evaluating segmentation algorithms are ‘goodness methods’, ‘discrepancy methods’ and ‘benchmarks’. Benchmarks are considered the most comprehensive method of evaluation. This paper shortcomings in current benchmark methods are identified and a framework is proposed that permits both a visual and numerical evaluation of segmentations for different algorithms, algorithm parameters and evaluation metrics. The concept of the framework is demonstrated on a real point cloud. Current results are promising and suggest that it can be used to predict the performance of segmentation algorithms.

  13. The Use of Treatment Concurrences to Assess Robustness of Binary Block Designs Against the Loss of Whole Blocks

    OpenAIRE

    Godolphin, JD; Godolphin, EJ

    2015-01-01

    © 2015 Australian Statistical Publishing Association Inc. Criteria are proposed for assessing the robustness of a binary block design against the loss of whole blocks, based on summing entries of selected upper non-principal sections of the concurrence matrix. These criteria improve on the minimal concurrence concept that has been used previously and provide new conditions for measuring the robustness status of a design. The robustness properties of two-associate partially balanced designs ar...

  14. Fully convolutional networks (FCNs)-based segmentation method for colorectal tumors on T2-weighted magnetic resonance images.

    Science.gov (United States)

    Jian, Junming; Xiong, Fei; Xia, Wei; Zhang, Rui; Gu, Jinhui; Wu, Xiaodong; Meng, Xiaochun; Gao, Xin

    2018-06-01

    Segmentation of colorectal tumors is the basis of preoperative prediction, staging, and therapeutic response evaluation. Due to the blurred boundary between lesions and normal colorectal tissue, it is hard to realize accurate segmentation. Routinely manual or semi-manual segmentation methods are extremely tedious, time-consuming, and highly operator-dependent. In the framework of FCNs, a segmentation method for colorectal tumor was presented. Normalization was applied to reduce the differences among images. Borrowing from transfer learning, VGG-16 was employed to extract features from normalized images. We conducted five side-output blocks from the last convolutional layer of each block of VGG-16 along the network, these side-output blocks can deep dive multiscale features, and produced corresponding predictions. Finally, all of the predictions from side-output blocks were fused to determine the final boundaries of the tumors. A quantitative comparison of 2772 colorectal tumor manual segmentation results from T2-weighted magnetic resonance images shows that the average Dice similarity coefficient, positive predictive value, specificity, sensitivity, Hammoude distance, and Hausdorff distance were 83.56, 82.67, 96.75, 87.85%, 0.2694, and 8.20, respectively. The proposed method is superior to U-net in colorectal tumor segmentation (P colorectal tumor segmentation (P > 0.05). The results indicate that the introduction of FCNs contributed to accurate segmentation of colorectal tumors. This method has the potential to replace the present time-consuming and nonreproducible manual segmentation method.

  15. E-Block: A Tangible Programming Tool with Graphical Blocks

    OpenAIRE

    Danli Wang; Yang Zhang; Shengyong Chen

    2013-01-01

    This paper designs a tangible programming tool, E-Block, for children aged 5 to 9 to experience the preliminary understanding of programming by building blocks. With embedded artificial intelligence, the tool defines the programming blocks with the sensors as the input and enables children to write programs to complete the tasks in the computer. The symbol on the programming block's surface is used to help children understanding the function of each block. The sequence information is transfer...

  16. Statistical segmentation of multidimensional brain datasets

    Science.gov (United States)

    Desco, Manuel; Gispert, Juan D.; Reig, Santiago; Santos, Andres; Pascau, Javier; Malpica, Norberto; Garcia-Barreno, Pedro

    2001-07-01

    This paper presents an automatic segmentation procedure for MRI neuroimages that overcomes part of the problems involved in multidimensional clustering techniques like partial volume effects (PVE), processing speed and difficulty of incorporating a priori knowledge. The method is a three-stage procedure: 1) Exclusion of background and skull voxels using threshold-based region growing techniques with fully automated seed selection. 2) Expectation Maximization algorithms are used to estimate the probability density function (PDF) of the remaining pixels, which are assumed to be mixtures of gaussians. These pixels can then be classified into cerebrospinal fluid (CSF), white matter and grey matter. Using this procedure, our method takes advantage of using the full covariance matrix (instead of the diagonal) for the joint PDF estimation. On the other hand, logistic discrimination techniques are more robust against violation of multi-gaussian assumptions. 3) A priori knowledge is added using Markov Random Field techniques. The algorithm has been tested with a dataset of 30 brain MRI studies (co-registered T1 and T2 MRI). Our method was compared with clustering techniques and with template-based statistical segmentation, using manual segmentation as a gold-standard. Our results were more robust and closer to the gold-standard.

  17. Medical image segmentation using improved FCM

    Institute of Scientific and Technical Information of China (English)

    ZHANG XiaoFeng; ZHANG CaiMing; TANG WenJing; WEI ZhenWen

    2012-01-01

    Image segmentation is one of the most important problems in medical image processing,and the existence of partial volume effect and other phenomena makes the problem much more complex. Fuzzy Cmeans,as an effective tool to deal with PVE,however,is faced with great challenges in efficiency.Aiming at this,this paper proposes one improved FCM algorithm based on the histogram of the given image,which will be denoted as HisFCM and divided into two phases.The first phase will retrieve several intervals on which to compute cluster centroids,and the second one will perform image segmentation based on improved FCM algorithm.Compared with FCM and other improved algorithms,HisFCM is of much higher efficiency with satisfying results.Experiments on medical images show that HisFCM can achieve good segmentation results in less than 0.1 second,and can satisfy real-time requirements of medical image processing.

  18. Robust Throughput Boosting for Low Latency Dynamic Partial Reconfiguration

    DEFF Research Database (Denmark)

    Nannarelli, Alberto; Re, M.; Cardarilli, Gian Carlo

    2017-01-01

    Reducing the configuration time of portions of an FPGA at run time is crucial in contemporary FPGA-based accelerators. In this work, we propose a method to increase the throughput for FPGA dynamic partial reconfiguration by using standard IP blocks. The throughput is increased by over-clocking th......Reducing the configuration time of portions of an FPGA at run time is crucial in contemporary FPGA-based accelerators. In this work, we propose a method to increase the throughput for FPGA dynamic partial reconfiguration by using standard IP blocks. The throughput is increased by over...

  19. Partial knee replacement - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series—Normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited ...

  20. Microlaparoscopic technique for partial salpingectomy using bipolar electrocoagulation.

    Science.gov (United States)

    Siegle, J C; Cartmell, L W; Rayburn, W F

    2001-07-01

    To describe a technique of performing a partial salpingectomy using a small-diameter (2-mm) laparoscope and bipolar electrocoagulation. Sixty consecutive women desiring permanent sterilization underwent laparoscopic partial salpingectomy using a 2-mm transumbilical laparoscope and secondary midline sites suprapubically and midway above the pubis. A midportion of the tube was coagulated using Kleppinger forceps, transected with scissors and removed using grasping forceps. Additional time to remove both coagulated tubal segments averaged 4 minutes (range, 3-10). Each segment (mean, 1.5 cm; range, 0.9-2.4 cm) was confirmed in the operating room, then histologically. The transected tubal edges were separated with no thermal injury to nearby structures and with no mesosalpingeal hemorrhage. No cases required conversion from microlaparoscopy to a traditional method, and recovery time was not prolonged. The puncture sites healed well without sutures. Successful removal of electrocoagulated tubal segments with histologic confirmation was undertaken microlaparoscopically, with minimal additional operative time.

  1. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2014-01-01

    A broad introduction to PDEs with an emphasis on specialized topics and applications occurring in a variety of fields Featuring a thoroughly revised presentation of topics, Beginning Partial Differential Equations, Third Edition provides a challenging, yet accessible,combination of techniques, applications, and introductory theory on the subjectof partial differential equations. The new edition offers nonstandard coverageon material including Burger's equation, the telegraph equation, damped wavemotion, and the use of characteristics to solve nonhomogeneous problems. The Third Edition is or

  2. Linoleum Block Printing Revisited.

    Science.gov (United States)

    Chetelat, Frank J.

    1980-01-01

    The author discusses practical considerations of teaching linoleum block printing in the elementary grades (tool use, materials, motivation) and outlines a sequence of design concepts in this area for the primary, intermediate and junior high grades. A short list of books and audiovisual aids is appended. (SJL)

  3. Spice Blocks Melanoma Growth

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    Curcumin, the pungent yellow spice found in both turmeric and curry powders, blocks a key biological pathway needed for development of melanoma and other cancers, according to a study that appears in the journal Cancer. Researchers from The University of Texas M. D. Anderson Cancer Center demonstrate how curcumin stops laboratory strains of…

  4. Contaminated soil concrete blocks

    NARCIS (Netherlands)

    de Korte, A.C.J.; Brouwers, Jos; Limbachiya, Mukesh C.; Kew, Hsein Y.

    2009-01-01

    According to Dutch law the contaminated soil needs to be remediated or immobilised. The main focus in this article is the design of concrete blocks, containing contaminated soil, that are suitable for large production, financial feasible and meets all technical and environmental requirements. In

  5. Optimally segmented magnetic structures

    DEFF Research Database (Denmark)

    Insinga, Andrea Roberto; Bahl, Christian; Bjørk, Rasmus

    We present a semi-analytical algorithm for magnet design problems, which calculates the optimal way to subdivide a given design region into uniformly magnetized segments.The availability of powerful rare-earth magnetic materials such as Nd-Fe-B has broadened the range of applications of permanent...... is not available.We will illustrate the results for magnet design problems from different areas, such as electric motors/generators (as the example in the picture), beam focusing for particle accelerators and magnetic refrigeration devices.......We present a semi-analytical algorithm for magnet design problems, which calculates the optimal way to subdivide a given design region into uniformly magnetized segments.The availability of powerful rare-earth magnetic materials such as Nd-Fe-B has broadened the range of applications of permanent...... magnets[1][2]. However, the powerful rare-earth magnets are generally expensive, so both the scientific and industrial communities have devoted a lot of effort into developing suitable design methods. Even so, many magnet optimization algorithms either are based on heuristic approaches[3...

  6. Segmentation of the Infant Food Market

    OpenAIRE

    Hrůzová, Daniela

    2015-01-01

    The theoretical part covers general market segmentation, namely the marketing importance of differences among consumers, the essence of market segmentation, its main conditions and the process of segmentation, which consists of four consecutive phases - defining the market, determining important criteria, uncovering segments and developing segment profiles. The segmentation criteria, segmentation approaches, methods and techniques for the process of market segmentation are also described in t...

  7. Lithium-drifted silicon detector with segmented contacts

    Science.gov (United States)

    Tindall, Craig S.; Luke, Paul N.

    2006-06-13

    A method and apparatus for creating both segmented and unsegmented radiation detectors which can operate at room temperature. The devices include a metal contact layer, and an n-type blocking contact formed from a thin layer of amorphous semiconductor. In one embodiment the material beneath the n-type contact is n-type material, such as lithium compensated silicon that forms the active region of the device. The active layer has been compensated to a degree at which the device may be fully depleted at low bias voltages. A p-type blocking contact layer, or a p-type donor material can be formed beneath a second metal contact layer to complete the device structure. When the contacts to the device are segmented, the device is capable of position sensitive detection and spectroscopy of ionizing radiation, such as photons, electrons, and ions.

  8. Quality-based fingerprint segmentation

    CSIR Research Space (South Africa)

    Mngenge, NA

    2012-06-01

    Full Text Available is block-wise, it utilizes the auto-correlation matrix of gradients and its eigenvalue to compute the score quality measure of each block. The score quality measures both local contrast and orientation in each block. The threshold is computed by taking...

  9. Report on ISS Oxygen Production, Resupply, and Partial Pressure Management

    Science.gov (United States)

    Schaezler, Ryan; Ghariani, Ahmed; Leonard, Daniel; Lehman, Daniel

    2011-01-01

    The majority of oxygen used on International Space Station (ISS) is for metabolic support and denitrogenation procedures prior to Extra-Vehicular Activities. Oxygen is supplied by various visiting vehicles such as the Progress and Shuttle in addition to oxygen production capability on both the United States On-Orbit Segment (USOS) and Russian Segment (RS). To maintain a habitable atmosphere the oxygen partial pressure is controlled between upper and lower bounds. The full range of the allowable oxygen partial pressure along with the increased ISS cabin volume is utilized as a buffer allowing days to pass between oxygen production or direct addition of oxygen to the atmosphere from reserves. This paper summarizes amount of oxygen supplied and produced from all of the sources and describes past experience of managing oxygen partial pressure along with the range of management options available to the ISS.

  10. Phasing multi-segment undulators

    International Nuclear Information System (INIS)

    Chavanne, J.; Elleaume, P.; Vaerenbergh, P. Van

    1996-01-01

    An important issue in the manufacture of multi-segment undulators as a source of synchrotron radiation or as a free-electron laser (FEL) is the phasing between successive segments. The state of the art is briefly reviewed, after which a novel pure permanent magnet phasing section that is passive and does not require any current is presented. The phasing section allows the introduction of a 6 mm longitudinal gap between each segment, resulting in complete mechanical independence and reduced magnetic interaction between segments. The tolerance of the longitudinal positioning of one segment with respect to the next is found to be 2.8 times lower than that of conventional phasing. The spectrum at all gaps and useful harmonics is almost unchanged when compared with a single-segment undulator of the same total length. (au) 3 refs

  11. The LOFT Ground Segment

    DEFF Research Database (Denmark)

    Bozzo, E.; Antonelli, A.; Argan, A.

    2014-01-01

    targets per orbit (~90 minutes), providing roughly ~80 GB of proprietary data per day (the proprietary period will be 12 months). The WFM continuously monitors about 1/3 of the sky at a time and provides data for about ~100 sources a day, resulting in a total of ~20 GB of additional telemetry. The LOFT...... Burst alert System additionally identifies on-board bright impulsive events (e.g., Gamma-ray Bursts, GRBs) and broadcasts the corresponding position and trigger time to the ground using a dedicated system of ~15 VHF receivers. All WFM data are planned to be made public immediately. In this contribution...... we summarize the planned organization of the LOFT ground segment (GS), as established in the mission Yellow Book 1 . We describe the expected GS contributions from ESA and the LOFT consortium. A review is provided of the planned LOFT data products and the details of the data flow, archiving...

  12. Segmented heat exchanger

    Science.gov (United States)

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  13. International EUREKA: Market Segment

    International Nuclear Information System (INIS)

    1982-03-01

    The purpose of the Market Segment of the EUREKA model is to simultaneously project uranium market prices, uranium supply and purchasing activities. The regional demands are extrinsic. However, annual forward contracting activities to meet these demands as well as inventory requirements are calculated. The annual price forecast is based on relatively short term, forward balances between available supply and desired purchases. The forecasted prices and extrapolated price trends determine decisions related to exploration and development, new production operations, and the operation of existing capacity. Purchasing and inventory requirements are also adjusted based on anticipated prices. The calculation proceeds one year at a time. Conditions calculated at the end of one year become the starting conditions for the calculation in the subsequent year

  14. Probabilistic retinal vessel segmentation

    Science.gov (United States)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  15. OASIS is Automated Statistical Inference for Segmentation, with applications to multiple sclerosis lesion segmentation in MRI.

    Science.gov (United States)

    Sweeney, Elizabeth M; Shinohara, Russell T; Shiee, Navid; Mateen, Farrah J; Chudgar, Avni A; Cuzzocreo, Jennifer L; Calabresi, Peter A; Pham, Dzung L; Reich, Daniel S; Crainiceanu, Ciprian M

    2013-01-01

    Magnetic resonance imaging (MRI) can be used to detect lesions in the brains of multiple sclerosis (MS) patients and is essential for diagnosing the disease and monitoring its progression. In practice, lesion load is often quantified by either manual or semi-automated segmentation of MRI, which is time-consuming, costly, and associated with large inter- and intra-observer variability. We propose OASIS is Automated Statistical Inference for Segmentation (OASIS), an automated statistical method for segmenting MS lesions in MRI studies. We use logistic regression models incorporating multiple MRI modalities to estimate voxel-level probabilities of lesion presence. Intensity-normalized T1-weighted, T2-weighted, fluid-attenuated inversion recovery and proton density volumes from 131 MRI studies (98 MS subjects, 33 healthy subjects) with manual lesion segmentations were used to train and validate our model. Within this set, OASIS detected lesions with a partial area under the receiver operating characteristic curve for clinically relevant false positive rates of 1% and below of 0.59% (95% CI; [0.50%, 0.67%]) at the voxel level. An experienced MS neuroradiologist compared these segmentations to those produced by LesionTOADS, an image segmentation software that provides segmentation of both lesions and normal brain structures. For lesions, OASIS out-performed LesionTOADS in 74% (95% CI: [65%, 82%]) of cases for the 98 MS subjects. To further validate the method, we applied OASIS to 169 MRI studies acquired at a separate center. The neuroradiologist again compared the OASIS segmentations to those from LesionTOADS. For lesions, OASIS ranked higher than LesionTOADS in 77% (95% CI: [71%, 83%]) of cases. For a randomly selected subset of 50 of these studies, one additional radiologist and one neurologist also scored the images. Within this set, the neuroradiologist ranked OASIS higher than LesionTOADS in 76% (95% CI: [64%, 88%]) of cases, the neurologist 66% (95% CI: [52%, 78

  16. SU-G-BRA-02: Development of a Learning Based Block Matching Algorithm for Ultrasound Tracking in Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, A; Bednarz, B [University of Wisconsin, Madison, WI (United States)

    2016-06-15

    Purpose: To develop an ultrasound learning-based tracking algorithm with the potential to provide real-time motion traces of anatomy-based fiducials that may aid in the effective delivery of external beam radiation. Methods: The algorithm was developed in Matlab R2015a and consists of two main stages: reference frame selection, and localized block matching. Immediately following frame acquisition, a normalized cross-correlation (NCC) similarity metric is used to determine a reference frame most similar to the current frame from a series of training set images that were acquired during a pretreatment scan. Segmented features in the reference frame provide the basis for the localized block matching to determine the feature locations in the current frame. The boundary points of the reference frame segmentation are used as the initial locations for the block matching and NCC is used to find the most similar block in the current frame. The best matched block locations in the current frame comprise the updated feature boundary. The algorithm was tested using five features from two sets of ultrasound patient data obtained from MICCAI 2014 CLUST. Due to the lack of a training set associated with the image sequences, the first 200 frames of the image sets were considered a valid training set for preliminary testing, and tracking was performed over the remaining frames. Results: Tracking of the five vessel features resulted in an average tracking error of 1.21 mm relative to predefined annotations. The average analysis rate was 15.7 FPS with analysis for one of the two patients reaching real-time speeds. Computations were performed on an i5-3230M at 2.60 GHz. Conclusion: Preliminary tests show tracking errors comparable with similar algorithms at close to real-time speeds. Extension of the work onto a GPU platform has the potential to achieve real-time performance, making tracking for therapy applications a feasible option. This work is partially funded by NIH grant R01CA

  17. SU-G-BRA-02: Development of a Learning Based Block Matching Algorithm for Ultrasound Tracking in Radiotherapy

    International Nuclear Information System (INIS)

    Shepard, A; Bednarz, B

    2016-01-01

    Purpose: To develop an ultrasound learning-based tracking algorithm with the potential to provide real-time motion traces of anatomy-based fiducials that may aid in the effective delivery of external beam radiation. Methods: The algorithm was developed in Matlab R2015a and consists of two main stages: reference frame selection, and localized block matching. Immediately following frame acquisition, a normalized cross-correlation (NCC) similarity metric is used to determine a reference frame most similar to the current frame from a series of training set images that were acquired during a pretreatment scan. Segmented features in the reference frame provide the basis for the localized block matching to determine the feature locations in the current frame. The boundary points of the reference frame segmentation are used as the initial locations for the block matching and NCC is used to find the most similar block in the current frame. The best matched block locations in the current frame comprise the updated feature boundary. The algorithm was tested using five features from two sets of ultrasound patient data obtained from MICCAI 2014 CLUST. Due to the lack of a training set associated with the image sequences, the first 200 frames of the image sets were considered a valid training set for preliminary testing, and tracking was performed over the remaining frames. Results: Tracking of the five vessel features resulted in an average tracking error of 1.21 mm relative to predefined annotations. The average analysis rate was 15.7 FPS with analysis for one of the two patients reaching real-time speeds. Computations were performed on an i5-3230M at 2.60 GHz. Conclusion: Preliminary tests show tracking errors comparable with similar algorithms at close to real-time speeds. Extension of the work onto a GPU platform has the potential to achieve real-time performance, making tracking for therapy applications a feasible option. This work is partially funded by NIH grant R01CA

  18. Segmented rail linear induction motor

    Science.gov (United States)

    Cowan, Jr., Maynard; Marder, Barry M.

    1996-01-01

    A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces.

  19. Structure-properties relationships of novel poly(carbonate-co-amide) segmented copolymers with polyamide-6 as hard segments and polycarbonate as soft segments

    Science.gov (United States)

    Yang, Yunyun; Kong, Weibo; Yuan, Ye; Zhou, Changlin; Cai, Xufu

    2018-04-01

    Novel poly(carbonate-co-amide) (PCA) block copolymers are prepared with polycarbonate diol (PCD) as soft segments, polyamide-6 (PA6) as hard segments and 4,4'-diphenylmethane diisocyanate (MDI) as coupling agent through reactive processing. The reactive processing strategy is eco-friendly and resolve the incompatibility between polyamide segments and PCD segments in preparation processing. The chemical structure, crystalline properties, thermal properties, mechanical properties and water resistance were extensively studied by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Differential scanning calorimetry (DSC), Thermal gravity analysis (TGA), Dynamic mechanical analysis (DMA), tensile testing, water contact angle and water absorption, respectively. The as-prepared PCAs exhibit obvious microphase separation between the crystalline hard PA6 phase and amorphous PCD soft segments. Meanwhile, PCAs showed outstanding mechanical with the maximum tensile strength of 46.3 MPa and elongation at break of 909%. The contact angle and water absorption results indicate that PCAs demonstrate outstanding water resistance even though possess the hydrophilic surfaces. The TGA measurements prove that the thermal stability of PCA can satisfy the requirement of multiple-processing without decomposition.

  20. Abdominal wall blocks in adults

    DEFF Research Database (Denmark)

    Børglum, Jens; Gögenür, Ismail; Bendtsen, Thomas F

    2016-01-01

    been introduced with success. Future research should also investigate the effect of specific abdominal wall blocks on neuroendocrine and inflammatory stress response after surgery.  Summary USG abdominal wall blocks in adults are commonplace techniques today. Most abdominal wall blocks are assigned......Purpose of review Abdominal wall blocks in adults have evolved much during the last decade; that is, particularly with the introduction of ultrasound-guided (USG) blocks. This review highlights recent advances of block techniques within this field and proposes directions for future research.......  Recent findings Ultrasound guidance is now considered the golden standard for abdominal wall blocks in adults, even though some landmark-based blocks are still being investigated. The efficiency of USG transversus abdominis plane blocks in relation to many surgical procedures involving the abdominal wall...

  1. SNUPPS power block engineering

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, C A [Bechtel Power Corp., San Francisco, Calif. (USA)

    1975-11-01

    The Standard Power Block is based on a modular concept and consists of the following: turbine building, auxiliary building, fuel building, control building, radwaste building, diesel generators building, and outside storage tanks and transformers. Each power block unit includes a Westinghouse pressurized water reactor and has a thermal power rating of 3425 MW(t). The corresponding General Electric turbine generator net electrical output is 1188 MW(e). This standardization approach results in not only a reduction in the costs of engineering, licensing, procurement, and project planning, but should also result in additional savings by the application of experience gained in the construction of the first unit to the following units and early input of construction data to design.

  2. Segmentation-DrivenTomographic Reconstruction

    DEFF Research Database (Denmark)

    Kongskov, Rasmus Dalgas

    such that the segmentation subsequently can be carried out by use of a simple segmentation method, for instance just a thresholding method. We tested the advantages of going from a two-stage reconstruction method to a one stage segmentation-driven reconstruction method for the phase contrast tomography reconstruction......The tomographic reconstruction problem is concerned with creating a model of the interior of an object from some measured data, typically projections of the object. After reconstructing an object it is often desired to segment it, either automatically or manually. For computed tomography (CT...

  3. Automated medical image segmentation techniques

    Directory of Open Access Journals (Sweden)

    Sharma Neeraj

    2010-01-01

    Full Text Available Accurate segmentation of medical images is a key step in contouring during radiotherapy planning. Computed topography (CT and Magnetic resonance (MR imaging are the most widely used radiographic techniques in diagnosis, clinical studies and treatment planning. This review provides details of automated segmentation methods, specifically discussed in the context of CT and MR images. The motive is to discuss the problems encountered in segmentation of CT and MR images, and the relative merits and limitations of methods currently available for segmentation of medical images.

  4. ADVANCED CLUSTER BASED IMAGE SEGMENTATION

    Directory of Open Access Journals (Sweden)

    D. Kesavaraja

    2011-11-01

    Full Text Available This paper presents efficient and portable implementations of a useful image segmentation technique which makes use of the faster and a variant of the conventional connected components algorithm which we call parallel Components. In the Modern world majority of the doctors are need image segmentation as the service for various purposes and also they expect this system is run faster and secure. Usually Image segmentation Algorithms are not working faster. In spite of several ongoing researches in Conventional Segmentation and its Algorithms might not be able to run faster. So we propose a cluster computing environment for parallel image Segmentation to provide faster result. This paper is the real time implementation of Distributed Image Segmentation in Clustering of Nodes. We demonstrate the effectiveness and feasibility of our method on a set of Medical CT Scan Images. Our general framework is a single address space, distributed memory programming model. We use efficient techniques for distributing and coalescing data as well as efficient combinations of task and data parallelism. The image segmentation algorithm makes use of an efficient cluster process which uses a novel approach for parallel merging. Our experimental results are consistent with the theoretical analysis and practical results. It provides the faster execution time for segmentation, when compared with Conventional method. Our test data is different CT scan images from the Medical database. More efficient implementations of Image Segmentation will likely result in even faster execution times.

  5. Change Around the Block?

    Science.gov (United States)

    Berlin, Joey

    2017-04-01

    Proponents of a block grant or per-capita cap trumpet them as vehicles for the federal government to give the states a capped amount of funding for Medicaid that legislatures would effectively distribute how they see fit. Questions abound as to what capped Medicaid funding would look like, and what effect it would have on the current Medicaid-eligible population, covered services, and physician payments.

  6. SUPERFICIAL CERVICAL PLEXUS BLOCK

    Directory of Open Access Journals (Sweden)

    Komang Mega Puspadisari

    2014-01-01

    Full Text Available Superficial cervical plexus block is one of the regional anesthesia in  neck were limited to thesuperficial fascia. Anesthesia is used to relieve pain caused either during or after the surgery iscompleted. This technique can be done by landmark or with ultrasound guiding. The midpointof posterior border of the Sternocleidomastoid was identified and the prosedure done on thatplace or on the level of cartilage cricoid.

  7. Partial differential equations

    CERN Document Server

    Evans, Lawrence C

    2010-01-01

    This text gives a comprehensive survey of modern techniques in the theoretical study of partial differential equations (PDEs) with particular emphasis on nonlinear equations. The exposition is divided into three parts: representation formulas for solutions; theory for linear partial differential equations; and theory for nonlinear partial differential equations. Included are complete treatments of the method of characteristics; energy methods within Sobolev spaces; regularity for second-order elliptic, parabolic, and hyperbolic equations; maximum principles; the multidimensional calculus of variations; viscosity solutions of Hamilton-Jacobi equations; shock waves and entropy criteria for conservation laws; and, much more.The author summarizes the relevant mathematics required to understand current research in PDEs, especially nonlinear PDEs. While he has reworked and simplified much of the classical theory (particularly the method of characteristics), he primarily emphasizes the modern interplay between funct...

  8. Compressive Strength Of Rice Husk Ash-Cement Sandcrete Blocks ...

    African Journals Online (AJOL)

    There is growing demand for alternative, low-cost building material in developing countries. The effect of partial substitution of ordinary Portland cement with Rice Husk Ash (RHA) on the compressive strength of hollow sandcrete block was investigated through laboratory experimental procedures. The specific gravity, initial ...

  9. Ameliorative Effects of Neurolytic Celiac Plexus Block on Stress and ...

    African Journals Online (AJOL)

    Purpose: To investigate effects of neurolytic celiac plexus block (NCPB) on stress and inflammation in rats with partial hepatectomy (PH). Methods: A model of PH rat was established, and serum C-reactive protein (CRP); corticosterone (GC); adrenocorticotropin (ACTH); noradrenaline (NA); adrenalin (AD); aspartate ...

  10. E-Block: A Tangible Programming Tool with Graphical Blocks

    Directory of Open Access Journals (Sweden)

    Danli Wang

    2013-01-01

    Full Text Available This paper designs a tangible programming tool, E-Block, for children aged 5 to 9 to experience the preliminary understanding of programming by building blocks. With embedded artificial intelligence, the tool defines the programming blocks with the sensors as the input and enables children to write programs to complete the tasks in the computer. The symbol on the programming block's surface is used to help children understanding the function of each block. The sequence information is transferred to computer by microcomputers and then translated into semantic information. The system applies wireless and infrared technologies and provides user with feedbacks on both screen and programming blocks. Preliminary user studies using observation and user interview methods are shown for E-Block's prototype. The test results prove that E-Block is attractive to children and easy to learn and use. The project also highlights potential advantages of using single chip microcomputer (SCM technology to develop tangible programming tools for children.

  11. Uranium City radiation reduction program: further studies on remedial measures and radon infiltration routes for houses with block walls

    International Nuclear Information System (INIS)

    Leung, M.K.

    1980-01-01

    This report describes the results of tests of partial sealing of concrete block walls to prevent radon infiltration into houses in Uranium City, and gives the results of studies of radon migration through concrete block walls. Results of some laboratory tests on the effectiveness of concrete blocks as a radon barrier are included

  12. Phase Separation and Elastic Properties of Poly(Trimethylene Terephthalate-block-poly(Ethylene Oxide Copolymers

    Directory of Open Access Journals (Sweden)

    Elżbieta Piesowicz

    2016-06-01

    Full Text Available A series of poly(trimethylene terephthalate-block-poly(ethylene oxide (PTT-b-PEOT copolymers with different compositions of rigid PTT and flexible PEOT segments were synthesized via condensation in the melt. The influence of the block length and the block ratio on the micro-separated phase structure and elastic properties of the synthesized multiblock copolymers was studied. The PEOT segments in these copolymers were kept constant at 1130, 2130 or 3130 g/mol, whereas the PTT content varied from 30 up to 50 wt %. The phase separation was assessed using differential scanning calorimetry (DSC and dynamic mechanical thermal analysis (DMTA. The crystal structure of the synthesised block copolymers and their microstructure on the manometer scale was evaluated by using WAXS and SAXS analysis. Depending on the PTT/PEOT ratio, but also on the rigid and flexible segment length in PTT-b-PEO copolymers, four different domains were observed i.e.,: a crystalline PTT phase, a crystalline PEO phase (which exists for the whole series based on three types of PEOT segments, an amorphous PTT phase (only at 50 wt % content of PTT rigid segments and an amorphous PEO phase. Moreover, the elastic deformability and reversibility of PTT-b-PEOT block copolymers were studied during a cyclic tensile test. Determined values of permanent set resultant from maximum attained stain (100% and 200% for copolymers were used to evaluate their elastic properties.

  13. Block and sub-block boundary strengthening in lath martensite

    NARCIS (Netherlands)

    Du, C.; Hoefnagels, J.P.M.; Vaes, R.; Geers, M.G.D.

    2016-01-01

    Well-defined uniaxial micro-tensile tests were performed on lath martensite single block specimens and multi-block specimens with different number of block boundaries parallel to the loading direction. Detailed slip trace analyses consistently revealed that in the {110}<111> slip system with the

  14. Segmented abutting fields irradiation using multileaf collimators

    International Nuclear Information System (INIS)

    Nishimura, Tetsuo

    1998-01-01

    The object of this study is to evaluate the clinical feasibility of segmented abutting fields irradiation (SAFI) using multileaf collimators (MLCs), in which the target volume is divided into several segments to create complex irregular field without use of alloy blocks. A linear accelerator with 26 pairs of roundly ended MLCs of 1 cm in width was tested in this study. In SAFI, radiation leakage occurs at the abutment sites with these MLCs. Film dosimetry was used to determine the optimal length of the MLC overlap to minimize dose profile variation in abutting fields. A mantle field was investigated as a clinical application. Without overlapping the MLCs, radiation leakage at the abutments appeared as a peak of the dose profile. With more overlapping, the profile exhibited a minimized variation with a two-peak pattern. With excessive overlapping, the peak was reversed due to decreased dose. Variation of the profile was minimized with an overlap of 2.0-2.2 mm. The level of variation and the optimal length of overlap were found to be independent of the sites of measurement. Reproducibility was confirmed by repeated measurements. With the mantle field, SAFI using MLCs revealed an profile equivalent to use of alloy blocking fields in all respects other than the variations at the abutting sites. If the length of the MLC abutment overlap differs by site, clinical application of SAFI using MLCs would be quite complicated. The optimal length of the overlap was found to be 2.0 mm and to be independent of the sites of abutment. Therefore, we conclude that SAFI using MLCs of 1 cm in width is feasible for clinical use. (author)

  15. Auxiliary partial liver transplantation

    NARCIS (Netherlands)

    C.B. Reuvers (Cornelis Bastiaan)

    1986-01-01

    textabstractIn this thesis studies on auxiliary partial liver transplantation in the dog and the pig are reported. The motive to perform this study was the fact that patients with acute hepatic failure or end-stage chronic liver disease are often considered to form too great a risk for successful

  16. Partial Remission Definition

    DEFF Research Database (Denmark)

    Andersen, Marie Louise Max; Hougaard, Philip; Pörksen, Sven

    2014-01-01

    OBJECTIVE: To validate the partial remission (PR) definition based on insulin dose-adjusted HbA1c (IDAA1c). SUBJECTS AND METHODS: The IDAA1c was developed using data in 251 children from the European Hvidoere cohort. For validation, 129 children from a Danish cohort were followed from the onset...

  17. Fundamental partial compositeness

    DEFF Research Database (Denmark)

    Sannino, Francesco; Strumia, Alessandro; Tesi, Andrea

    2016-01-01

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Unde...

  18. Partially ordered models

    NARCIS (Netherlands)

    Fernandez, R.; Deveaux, V.

    2010-01-01

    We provide a formal definition and study the basic properties of partially ordered chains (POC). These systems were proposed to model textures in image processing and to represent independence relations between random variables in statistics (in the later case they are known as Bayesian networks).

  19. Partially Hidden Markov Models

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Rissanen, Jorma

    1996-01-01

    Partially Hidden Markov Models (PHMM) are introduced. They differ from the ordinary HMM's in that both the transition probabilities of the hidden states and the output probabilities are conditioned on past observations. As an illustration they are applied to black and white image compression where...

  20. Honesty in partial logic

    NARCIS (Netherlands)

    W. van der Hoek (Wiebe); J.O.M. Jaspars; E. Thijsse

    1995-01-01

    textabstractWe propose an epistemic logic in which knowledge is fully introspective and implies truth, although truth need not imply epistemic possibility. The logic is presented in sequential format and is interpreted in a natural class of partial models, called balloon models. We examine the

  1. Habitat Blocks and Wildlife Corridors

    Data.gov (United States)

    Vermont Center for Geographic Information — Habitat blocks are areas of contiguous forest and other natural habitats that are unfragmented by roads, development, or agriculture. Vermonts habitat blocks are...

  2. Atrioventricular block, ECG tracing (image)

    Science.gov (United States)

    ... an abnormal rhythm (arrhythmia) called an atrioventricular (AV) block. P waves show that the top of the ... wave (and heart contraction), there is an atrioventricular block, and a very slow pulse (bradycardia).

  3. Region segmentation along image sequence

    International Nuclear Information System (INIS)

    Monchal, L.; Aubry, P.

    1995-01-01

    A method to extract regions in sequence of images is proposed. Regions are not matched from one image to the following one. The result of a region segmentation is used as an initialization to segment the following and image to track the region along the sequence. The image sequence is exploited as a spatio-temporal event. (authors). 12 refs., 8 figs

  4. Market segmentation using perceived constraints

    Science.gov (United States)

    Jinhee Jun; Gerard Kyle; Andrew Mowen

    2008-01-01

    We examined the practical utility of segmenting potential visitors to Cleveland Metroparks using their constraint profiles. Our analysis identified three segments based on their scores on the dimensions of constraints: Other priorities--visitors who scored the highest on 'other priorities' dimension; Highly Constrained--visitors who scored relatively high on...

  5. Market Segmentation: An Instructional Module.

    Science.gov (United States)

    Wright, Peter H.

    A concept-based introduction to market segmentation is provided in this instructional module for undergraduate and graduate transportation-related courses. The material can be used in many disciplines including engineering, business, marketing, and technology. The concept of market segmentation is primarily a transportation planning technique by…

  6. IFRS 8 – OPERATING SEGMENTS

    Directory of Open Access Journals (Sweden)

    BOCHIS LEONICA

    2009-05-01

    Full Text Available Segment reporting in accordance with IFRS 8 will be mandatory for annual financial statements covering periods beginning on or after 1 January 2009. The standards replaces IAS 14, Segment Reporting, from that date. The objective of IFRS 8 is to require

  7. Reduplication Facilitates Early Word Segmentation

    Science.gov (United States)

    Ota, Mitsuhiko; Skarabela, Barbora

    2018-01-01

    This study explores the possibility that early word segmentation is aided by infants' tendency to segment words with repeated syllables ("reduplication"). Twenty-four nine-month-olds were familiarized with passages containing one novel reduplicated word and one novel non-reduplicated word. Their central fixation times in response to…

  8. The Importance of Marketing Segmentation

    Science.gov (United States)

    Martin, Gillian

    2011-01-01

    The rationale behind marketing segmentation is to allow businesses to focus on their consumers' behaviors and purchasing patterns. If done effectively, marketing segmentation allows an organization to achieve its highest return on investment (ROI) in turn for its marketing and sales expenses. If an organization markets its products or services to…

  9. Essays in international market segmentation

    NARCIS (Netherlands)

    Hofstede, ter F.

    1999-01-01

    The primary objective of this thesis is to develop and validate new methodologies to improve the effectiveness of international segmentation strategies. The current status of international market segmentation research is reviewed in an introductory chapter, which provided a number of

  10. APPLICATION SEGMENT ANALYSISFOR THE DEVELOPMENT STRATEGYEDUCATIONAL INSTITUTION

    Directory of Open Access Journals (Sweden)

    G. V. Alekseev

    2015-01-01

    Full Text Available Summary. Applicable at present methods of the shaping to strategies of the development of the educational institutions not always objective take into account the mutual influence and receivership separate structured and organizing block to organizations of the scholastic process, in particular work with applicant. The Article is dedicated to discussing the possibilities of the using the segment analysis for development of the strategies of the development of the educational institutions for the reason increasing produced specialist on the market of the labour real sector economy. In her is described possibility to formalize the choice of the marketing methods within the framework of approach of the stochastic programming, as section of the ill-defined logic (fuzzy logic, which is a generalizations classical theory of sets and classical formal logic. The Main reason of the using of such approach became presence ill-defined and drawn near discourses at description of the preferences applicant, quality of the formation, but consequently and missions of the educational institution. The Decision of the specified problems in significant measure promotes the ill-defined approach to modeling of the complex systems, which has obtained recognition all over the world for use the most most important factors and methods of the determination to value of the balance marketing approach on the base of the segment analysis and base expert estimation, for what is formed corresponding to about-gram for COMPUTER realizing specified approaches.

  11. Algebraic partial Boolean algebras

    International Nuclear Information System (INIS)

    Smith, Derek

    2003-01-01

    Partial Boolean algebras, first studied by Kochen and Specker in the 1960s, provide the structure for Bell-Kochen-Specker theorems which deny the existence of non-contextual hidden variable theories. In this paper, we study partial Boolean algebras which are 'algebraic' in the sense that their elements have coordinates in an algebraic number field. Several of these algebras have been discussed recently in a debate on the validity of Bell-Kochen-Specker theorems in the context of finite precision measurements. The main result of this paper is that every algebraic finitely-generated partial Boolean algebra B(T) is finite when the underlying space H is three-dimensional, answering a question of Kochen and showing that Conway and Kochen's infinite algebraic partial Boolean algebra has minimum dimension. This result contrasts the existence of an infinite (non-algebraic) B(T) generated by eight elements in an abstract orthomodular lattice of height 3. We then initiate a study of higher-dimensional algebraic partial Boolean algebras. First, we describe a restriction on the determinants of the elements of B(T) that are generated by a given set T. We then show that when the generating set T consists of the rays spanning the minimal vectors in a real irreducible root lattice, B(T) is infinite just if that root lattice has an A 5 sublattice. Finally, we characterize the rays of B(T) when T consists of the rays spanning the minimal vectors of the root lattice E 8

  12. suitability of electric arc furnace (eaf) slag as partial replacement for ...

    African Journals Online (AJOL)

    Administrator

    investigated for use as a partial replacement for cement in sandcrete blocks. The tests ... some economic benefit and as well mitigate the negative impact of this waste on the environment. ... course of production of steel typically in the ratio.

  13. Fermion-scalar conformal blocks

    Energy Technology Data Exchange (ETDEWEB)

    Iliesiu, Luca [Joseph Henry Laboratories, Princeton University,Washington Road, Princeton, NJ 08544 (United States); Kos, Filip [Department of Physics, Yale University,217 Prospect Street, New Haven, CT 06520 (United States); Poland, David [Department of Physics, Yale University,217 Prospect Street, New Haven, CT 06520 (United States); School of Natural Sciences, Institute for Advanced Study,1 Einstein Dr, Princeton, New Jersey 08540 (United States); Pufu, Silviu S. [Joseph Henry Laboratories, Princeton University,Washington Road, Princeton, NJ 08544 (United States); Simmons-Duffin, David [School of Natural Sciences, Institute for Advanced Study,1 Einstein Dr, Princeton, New Jersey 08540 (United States); Yacoby, Ran [Joseph Henry Laboratories, Princeton University,Washington Road, Princeton, NJ 08544 (United States)

    2016-04-13

    We compute the conformal blocks associated with scalar-scalar-fermion-fermion 4-point functions in 3D CFTs. Together with the known scalar conformal blocks, our result completes the task of determining the so-called ‘seed blocks’ in three dimensions. Conformal blocks associated with 4-point functions of operators with arbitrary spins can now be determined from these seed blocks by using known differential operators.

  14. Powder wastes confinement block and manufacturing process of this block

    International Nuclear Information System (INIS)

    Dagot, L.; Brunel, G.

    1996-01-01

    This invention concerns a powder wastes containment block and a manufacturing process of this block. In this block, the waste powder is encapsulated in a thermo hardening polymer as for example an epoxy resin, the encapsulated resin being spread into cement. This block can contain between 45 and 55% in mass of wastes, between 18 and 36% in mass of polymer and between 14 and 32% in mass of cement. Such a containment block can be used for the radioactive wastes storage. (O.M.). 4 refs

  15. Role of loop L5-6 connecting transmembrane segments M5 and M6 in biogenesis and functioning of yeast Pma1 H+-ATPase.

    Science.gov (United States)

    Petrov, V V

    2015-01-01

    The L5-6 loop is a short extracytoplasmic stretch (714-DNSLDID) connecting transmembrane segments M5 and M6 and forming along with segments M4 and M8 the core through which cations are transported by H+-, Ca2+-, K+,Na+-, H+,K+-, and other P2-ATPases. To study structure-function relationships within this loop of the yeast plasma membrane Pma1 H+-ATPase, alanine- and cysteine-scanning mutagenesis has been employed. Ala and Cys substitutions for the most conserved residue (Leu717) led to complete block in biogenesis preventing the enzyme from reaching secretory vesicles. The Ala replacement at Asp714 led to five-fold decrease in the mutant expression and loss of its activity, while the Cys substitution blocked biogenesis completely. Replacements of other residues did not lead to loss of enzymatic activity. Additional replacements were made for Asp714 and Asp720 (Asp®Asn/Glu). Of the substitutions made at Asp714, only D714N partially restored the mutant enzyme biogenesis and functioning. However, all mutant enzymes with substituted Asp720 were active. The expressed mutants (34-95% of the wild-type level) showed activity high enough (35-108%) to be analyzed in detail. One of the mutants (I719A) had three-fold reduced coupling ratio between ATP hydrolysis and H+ transport; however, the I719C mutation was rather indistinguishable from the wild-type enzyme. Thus, substitutions at two of the seven positions seriously affected biogenesis and/or functioning of the enzyme. Taken together, these results suggest that the M5-M6 loop residues play an important role in protein stability and function, and they are probably responsible for proper arrangement of transmembrane segments M5 and M6 and other domains of the enzyme. This might also be important for the regulation of the enzyme.

  16. Fully Aromatic Block Copolymers for Fuel Cell Membranes with Densely Sulfonated Nanophase Domains

    DEFF Research Database (Denmark)

    Takamuku, Shogo; Jannasch, Patrick; Lund, Peter Brilner

    Two multiblock copoly(arylene ether sulfone)s with similar block lengths and ion exchange capacities (IECs) were prepared by a coupling reaction between a non-sulfonated precursor block and a highly sulfonated precursor block containing either fully disulfonated diarylsulfone or fully...... tetrasulfonated tetraaryldisulfone segments. The latter two precursor blocks were sulfonated via lithiation-sulfination reactions whereby the sulfonic acid groups were exclu- sively placed in ortho positions to the many sulfone bridges, giving these locks IECs of 4.1 and 4.6 meqg1, respectively. Copolymer...

  17. Infrared Image Segmentation by Combining Fractal Geometry with Wavelet Transformation

    Directory of Open Access Journals (Sweden)

    Xionggang Tu

    2014-11-01

    Full Text Available An infrared image is decomposed into three levels by discrete stationary wavelet transform (DSWT. Noise is reduced by wiener filter in the high resolution levels in the DSWT domain. Nonlinear gray transformation operation is used to enhance details in the low resolution levels in the DSWT domain. Enhanced infrared image is obtained by inverse DSWT. The enhanced infrared image is divided into many small blocks. The fractal dimensions of all the blocks are computed. Region of interest (ROI is extracted by combining all the blocks, which have similar fractal dimensions. ROI is segmented by global threshold method. The man-made objects are efficiently separated from the infrared image by the proposed method.

  18. Segmentation of urinary bladder in CT Urography (CTU) using CLASS

    Science.gov (United States)

    Hadjiiski, Lubomir; Chan, Heang-Ping; Law, Yuen; Cohan, Richard H.; Caoili, Elaine M.; Cho, Hyun-Chong; Zhou, Chuan; Wei, Jun

    2012-03-01

    We are developing a computerized system for bladder segmentation on CTU, as a critical component for computer aided diagnosis of bladder cancer. A challenge for bladder segmentation is the presence of regions without contrast (NC) and filled with IV contrast (C). We are developing a Conjoint Level set Analysis and Segmentation System (CLASS) specifically for this application. CLASS performs a series of image processing tasks: preprocessing, initial segmentation, and 3D and 2D level set segmentation and post-processing, designed according to the characteristics of the bladder in CTU. The NC and the C regions of the bladder were segmented separately in CLASS. The final contour is obtained in the post-processing stage by the union of the NC and C contours. Seventy bladders (31 containing lesions, 24 containing wall thickening, and 15 normal) were segmented. The performance of CLASS was assessed by rating the quality of the contours on a 5-point scale (1= "very poor", 3= "fair", 5 = "excellent"). For the 53 partially contrast-filled bladders, the average quality ratings for the 53 NC and 53 C regions were 4.0+/-0.7 and 4.0+/-1.0, respectively. 46 NC and 41 C regions were given quality ratings of 4 or above. Only 2 NC and 5 C regions had ratings under 3. The average quality ratings for the remaining 12 completely no contrast (NC) and 5 completely contrast-filled (C) bladder contours were 3.3+/-1.0 and 3.4+/-0.5, respectively. After combining the NC and C contours for each of the 70 bladders, 46 had quality ratings of 4 or above. Only 4 had ratings under 3. The average quality rating was 3.8+/-0.7. The results demonstrate the potential of CLASS for automated segmentation of the bladder.

  19. Building Curriculum during Block Play

    Science.gov (United States)

    Andrews, Nicole

    2015-01-01

    Blocks are not just for play! In this article, Nicole Andrews describes observing the interactions of three young boys enthusiastically engaged in the kindergarten block center of their classroom, using blocks in a building project that displayed their ability to use critical thinking skills, physics exploration, and the development of language…

  20. Isotope heating block

    International Nuclear Information System (INIS)

    Wenk, E.

    1976-01-01

    A suggestion is made not to lead the separated nuclear 'waste' from spent nuclear fuel elements directly to end storage, but to make use of the heat produced from the remaining radiation, e.g. for seawater desalination. According to the invention, the activated fission products are to be processed, e.g. by calcination or vitrification, so that one can handle them. They should then be arranged in layers alternately with plate-shaped heat conducting pipes to form a homogeneous block; the heat absorbed by the thermal plates should be further passed on to evaporators or heat exchangers. (UWI) [de

  1. Blocking the Hawking radiation

    DEFF Research Database (Denmark)

    Autzen, M.; Kouvaris, C.

    2014-01-01

    grows after its formation (and eventually destroys the star) instead of evaporating. The fate of the black hole is dictated by the two opposite mechanics, i.e., accretion of nuclear matter from the center of the star and Hawking radiation that tends to decrease the mass of the black hole. We study how...... the assumptions for the accretion rate can in fact affect the critical mass beyond which a black hole always grows. We also study to what extent degenerate nuclear matter can impede Hawking radiation due to the fact that emitted particles can be Pauli blocked at the core of the star....

  2. Segmentation of Connective Tissue in Meat from Microtomography Using a Grating Interferometer

    DEFF Research Database (Denmark)

    Einarsdottir, Hildur; Ersbøll, Bjarne Kjær; Larsen, Rasmus

    microtomography provides high resolution, the thin structures of the connective tissues are difficult to segment. This is mainly due to partial object voxels, image noise and artifacts. The segmentation of connective tissue is important for quantitative analysis purposes. Factors such as the surface area......, relative volume and the statistics of the electron density of the connective tissue could prove useful for understanding the structural changes occurring in the meat sample due to heat treatment. In this study a two step segmentation algorithm was implemented in order to segment connective tissue from...... the a priori probability of neighborhood dependencies, and the field can either be isotropic or anisotropic. For the segmentation of connective tissue, the local information of the structure orientation and coherence is extracted to steer the smoothing (anisotropy) of the final segmentation. The results show...

  3. Learning of perceptual grouping for object segmentation on RGB-D data.

    Science.gov (United States)

    Richtsfeld, Andreas; Mörwald, Thomas; Prankl, Johann; Zillich, Michael; Vincze, Markus

    2014-01-01

    Object segmentation of unknown objects with arbitrary shape in cluttered scenes is an ambitious goal in computer vision and became a great impulse with the introduction of cheap and powerful RGB-D sensors. We introduce a framework for segmenting RGB-D images where data is processed in a hierarchical fashion. After pre-clustering on pixel level parametric surface patches are estimated. Different relations between patch-pairs are calculated, which we derive from perceptual grouping principles, and support vector machine classification is employed to learn Perceptual Grouping. Finally, we show that object hypotheses generation with Graph-Cut finds a globally optimal solution and prevents wrong grouping. Our framework is able to segment objects, even if they are stacked or jumbled in cluttered scenes. We also tackle the problem of segmenting objects when they are partially occluded. The work is evaluated on publicly available object segmentation databases and also compared with state-of-the-art work of object segmentation.

  4. Segmental vitiligo with segmental morphea: An autoimmune link?

    Directory of Open Access Journals (Sweden)

    Pravesh Yadav

    2014-01-01

    Full Text Available An 18-year old girl with segmental vitiligo involving the left side of the trunk and left upper limb with segmental morphea involving the right side of trunk and right upper limb without any deeper involvement is illustrated. There was no history of preceding drug intake, vaccination, trauma, radiation therapy, infection, or hormonal therapy. Family history of stable vitiligo in her brother and a history of type II diabetes mellitus in the father were elicited. Screening for autoimmune diseases and antithyroid antibody was negative. An autoimmune link explaining the co-occurrence has been proposed. Cutaneous mosiacism could explain the presence of both the pathologies in a segmental distribution.

  5. Segmentation Toolbox for Tomographic Image Data

    DEFF Research Database (Denmark)

    Einarsdottir, Hildur

    , techniques to automatically analyze such data becomes ever more important. Most segmentation methods for large datasets, such as CT images, deal with simple thresholding techniques, where intensity values cut offs are predetermined and hard coded. For data where the intensity difference is not sufficient......Motivation: Image acquisition has vastly improved over the past years, introducing techniques such as X-ray computed tomography (CT). CT images provide the means to probe a sample non-invasively to investigate its inner structure. Given the wide usage of this technique and massive data amounts......, and partial volume voxels occur frequently, thresholding methods do not suffice and more advanced methods are required. Contribution: To meet these requirements a toolbox has been developed, combining well known methods within the image analysis field. The toolbox includes cluster-based methods...

  6. Frictionless segmented mechanics for controlled space closure.

    Science.gov (United States)

    Andrade, Ildeu

    2017-02-01

    Extraction spaces may be needed to achieve specific orthodontic goals of positioning the dentition in harmony with the craniofacial complex. However, the fundamental reality that determines the occlusion final position is the control exerted by the orthodontist while closing the extraction spaces. A specific treatment objective may require the posterior teeth to remain in a constant position anteroposteriorly as well as vertically, while the anterior teeth occupy the entire extraction site. Another treatment objective may require the opposite, or any number of intentional alternatives of extraction site closure. The present case report describes a simple controlled segmented mechanic system that permitted definable and predictable force systems to be applied and allowed to predict the treatment outcome with confidence. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) in partial fulfillment of the requirements for Diplomate certification.

  7. Frictionless segmented mechanics for controlled space closure

    Directory of Open Access Journals (Sweden)

    Ildeu Andrade Jr

    Full Text Available ABSTRACT Extraction spaces may be needed to achieve specific orthodontic goals of positioning the dentition in harmony with the craniofacial complex. However, the fundamental reality that determines the occlusion final position is the control exerted by the orthodontist while closing the extraction spaces. A specific treatment objective may require the posterior teeth to remain in a constant position anteroposteriorly as well as vertically, while the anterior teeth occupy the entire extraction site. Another treatment objective may require the opposite, or any number of intentional alternatives of extraction site closure. The present case report describes a simple controlled segmented mechanic system that permitted definable and predictable force systems to be applied and allowed to predict the treatment outcome with confidence. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO in partial fulfillment of the requirements for Diplomate certification.

  8. A standard graphite block

    Energy Technology Data Exchange (ETDEWEB)

    Ivkovic, M; Zdravkovic, Z; Sotic, O [Department of Reactor Physics and Dynamics, Boris Kidric Institute of nuclear sciences Vinca, Belgrade (Yugoslavia)

    1966-04-15

    A graphite block was calibrated for the thermal neutron flux of the Ra-Be source using indium foils as detectors. Experimental values of the thermal neutron flux along the central vertical axis of the system were corrected for the self-shielding effect and depression of flux in the detector. The experimental values obtained were compared with the values calculated on the basis of solving the conservation neutron equation by the continuous slowing-down theory. In this theoretical calculation of the flux the Ra-Be source was divided into three resonance energy regions. The measurement of the thermal neutron diffusion length in the standard graphite block is described. The measurements were performed in the thermal neutron region of the system. The experimental results were interpreted by the diffusion theory for point thermal neutron source in the finite system. The thermal neutron diffusion length was calculated to be L= 50.9 {+-}3.1 cm for the following graphite characteristics: density = 1.7 g/cm{sup 3}; boron content = 0.1 ppm; absorption cross section = 3.7 mb.

  9. A standard graphite block

    International Nuclear Information System (INIS)

    Ivkovic, M.; Zdravkovic, Z.; Sotic, O.

    1966-04-01

    A graphite block was calibrated for the thermal neutron flux of the Ra-Be source using indium foils as detectors. Experimental values of the thermal neutron flux along the central vertical axis of the system were corrected for the self-shielding effect and depression of flux in the detector. The experimental values obtained were compared with the values calculated on the basis of solving the conservation neutron equation by the continuous slowing-down theory. In this theoretical calculation of the flux the Ra-Be source was divided into three resonance energy regions. The measurement of the thermal neutron diffusion length in the standard graphite block is described. The measurements were performed in the thermal neutron region of the system. The experimental results were interpreted by the diffusion theory for point thermal neutron source in the finite system. The thermal neutron diffusion length was calculated to be L= 50.9 ±3.1 cm for the following graphite characteristics: density = 1.7 g/cm 3 ; boron content = 0.1 ppm; absorption cross section = 3.7 mb

  10. Segmentation of the geographic atrophy in spectral-domain optical coherence tomography and fundus autofluorescence images.

    Science.gov (United States)

    Hu, Zhihong; Medioni, Gerard G; Hernandez, Matthias; Hariri, Amirhossein; Wu, Xiaodong; Sadda, Srinivas R

    2013-12-30

    Geographic atrophy (GA) is the atrophic late-stage manifestation of age-related macular degeneration (AMD), which may result in severe vision loss and blindness. The purpose of this study was to develop a reliable, effective approach for GA segmentation in both spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF) images using a level set-based approach and to compare the segmentation performance in the two modalities. To identify GA regions in SD-OCT images, three retinal surfaces were first segmented in volumetric SD-OCT images using a double-surface graph search scheme. A two-dimensional (2-D) partial OCT projection image was created from the segmented choroid layer. A level set approach was applied to segment the GA in the partial OCT projection image. In addition, the algorithm was applied to FAF images for the GA segmentation. Twenty randomly chosen macular SD-OCT (Zeiss Cirrus) volumes and 20 corresponding FAF (Heidelberg Spectralis) images were obtained from 20 subjects with GA. The algorithm-defined GA region was compared with consensus manual delineation performed by certified graders. The mean Dice similarity coefficients (DSC) between the algorithm- and manually defined GA regions were 0.87 ± 0.09 in partial OCT projection images and 0.89 ± 0.07 in registered FAF images. The area correlations between them were 0.93 (P segment GA regions in both SD-OCT and FAF images. This approach demonstrated good agreement between the algorithm- and manually defined GA regions within each single modality. The GA segmentation in FAF images performed better than in partial OCT projection images. Across the two modalities, the GA segmentation presented reasonable agreement.

  11. Partially composite Higgs models

    DEFF Research Database (Denmark)

    Alanne, Tommi; Buarque Franzosi, Diogo; Frandsen, Mads T.

    2018-01-01

    We study the phenomenology of partially composite-Higgs models where electroweak symmetry breaking is dynamically induced, and the Higgs is a mixture of a composite and an elementary state. The models considered have explicit realizations in terms of gauge-Yukawa theories with new strongly...... interacting fermions coupled to elementary scalars and allow for a very SM-like Higgs state. We study constraints on their parameter spaces from vacuum stability and perturbativity as well as from LHC results and find that requiring vacuum stability up to the compositeness scale already imposes relevant...... constraints. A small part of parameter space around the classically conformal limit is stable up to the Planck scale. This is however already strongly disfavored by LHC results. in different limits, the models realize both (partially) composite-Higgs and (bosonic) technicolor models and a dynamical extension...

  12. Synthesis of amphiphilic poly(ε-caprolactone)-b-poly( N-vinylcaprolactam) block copolymers via the combination of RAFT polymerization and click chemistry

    International Nuclear Information System (INIS)

    Assis, Paulo Henrique; Aguiar, Graziele Aparecida de Jesus; Moraes, Rodolfo Minto de; Medeiros, Simone de Fatima; Santos, Amilton Martins

    2016-01-01

    Full text: In recent years, well-defined block copolymers composed of a hydrophilic and hydrophobic segments have gained much interest as drug carriers, because of their enhanced solubility and sustained release of the drug in controlled delivery systems [1]. The development of strategies to obtain block copolymers has attracted considerable attention, due to the possibility to combine characteristic properties of the homopolymers. A wide variety of well-defined block copolymers have been successfully synthesized by combining the efficiency and selectivity of click chemistry with the powerful RAFT polymerization mechanism. In the present work, well-defined amphiphilic, biocompatible, partially biodegradable, and thermosensitive poly(ε-caprolactone)-b-poly(N-vinylcaprolactam) (PCL-b-PNVCL) block copolymers were synthesized by combining ring opening polymerization (ROP), reversible addition-fragmentation chain transfer (RAFT) polymerization and subsequent click chemistry reaction. Alkyne-terminated poly(ε-caprolactone) (alkyne-PCL) was obtained by the ring opening polymerization of ε-caprolactone (ε-CL) using propargyl alcohol as initiator and stannous-2-ethylhexanoate [Sn(Oct) 2 ] as catalyst. The azide end-capped-poly(N-vinylcaprolactam) (PNVCL-N 3 ) was synthesized by reversible addition-fragmentation chain transfer/macromolecular design via interchange of xanthates (RAFT/MADIX) polymerization of the N-vinylcaprolactam (NVCL) mediated by a novel chain transfer agent comprising an azide function , 2-azidoethyl[(ethoxycarbonothioyl)thio](phenyl)acetate. These functionalized homopolymers, alkyne-PCL and PNVCL-N 3 , were coupled by the 1,3 dipolar cycloaddition reaction in order to obtain the corresponding block copolymers. These (co)polymers were characterized by FTIR, 1 H NMR and GPC measurements. Reference: 1. RAMESH, K., SINGH, S., MITRA, K., CHATTOPADHYAY, D., MISRA, N., & RAY, B. (2015). Colloid and Polymer Science, 1-9. (author)

  13. Using Predictability for Lexical Segmentation.

    Science.gov (United States)

    Çöltekin, Çağrı

    2017-09-01

    This study investigates a strategy based on predictability of consecutive sub-lexical units in learning to segment a continuous speech stream into lexical units using computational modeling and simulations. Lexical segmentation is one of the early challenges during language acquisition, and it has been studied extensively through psycholinguistic experiments as well as computational methods. However, despite strong empirical evidence, the explicit use of predictability of basic sub-lexical units in models of segmentation is underexplored. This paper presents an incremental computational model of lexical segmentation for exploring the usefulness of predictability for lexical segmentation. We show that the predictability cue is a strong cue for segmentation. Contrary to earlier reports in the literature, the strategy yields state-of-the-art segmentation performance with an incremental computational model that uses only this particular cue in a cognitively plausible setting. The paper also reports an in-depth analysis of the model, investigating the conditions affecting the usefulness of the strategy. Copyright © 2016 Cognitive Science Society, Inc.

  14. Photogenic partial seizures.

    Science.gov (United States)

    Hennessy, M J; Binnie, C D

    2000-01-01

    To establish the incidence and symptoms of partial seizures in a cohort of patients investigated on account of known sensitivity to intermittent photic stimulation and/or precipitation of seizures by environmental visual stimuli such as television (TV) screens or computer monitors. We report 43 consecutive patients with epilepsy, who had exhibited a significant EEG photoparoxysmal response or who had seizures precipitated by environmental visual stimuli and underwent detailed assessment of their photosensitivity in the EEG laboratory, during which all were questioned concerning their ictal symptoms. All patients were considered on clinical grounds to have an idiopathic epilepsy syndrome. Twenty-eight (65%) patients reported visually precipitated attacks occurring initially with maintained consciousness, in some instances evolving to a period of confusion or to a secondarily generalized seizure. Visual symptoms were most commonly reported and included positive symptoms such as coloured circles or spots, but also blindness and subjective symptoms such as "eyes going funny." Other symptoms described included nonspecific cephalic sensations, deja-vu, auditory hallucinations, nausea, and vomiting. No patient reported any clear spontaneous partial seizures, and there were no grounds for supposing that any had partial epilepsy excepting the ictal phenomenology of some or all of the visually induced attacks. These findings provide clinical support for the physiological studies that indicate that the trigger mechanism for human photosensitivity involves binocularly innervated cells located in the visual cortex. Thus the visual cortex is the seat of the primary epileptogenic process, and the photically triggered discharges and seizures may be regarded as partial with secondary generalization.

  15. Arthroscopic partial medial meniscectomy

    Directory of Open Access Journals (Sweden)

    Dašić Žarko

    2011-01-01

    Full Text Available Background/Aim. Meniscal injuries are common in professional or recreational sports as well as in daily activities. If meniscal lesions lead to physical impairment they usually require surgical treatment. Arthroscopic treatment of meniscal injuries is one of the most often performed orthopedic operative procedures. Methods. The study analyzed the results of arthroscopic partial medial meniscectomy in 213 patients in a 24-month period, from 2006, to 2008. Results. In our series of arthroscopically treated medial meniscus tears we noted 78 (36.62% vertical complete bucket handle lesions, 19 (8.92% vertical incomplete lesions, 18 (8.45% longitudinal tears, 35 (16.43% oblique tears, 18 (8.45% complex degenerative lesions, 17 (7.98% radial lesions and 28 (13.14% horisontal lesions. Mean preoperative International Knee Documentation Committee (IKDC score was 49.81%, 1 month after the arthroscopic partial medial meniscectomy the mean IKDC score was 84.08%, and 6 months after mean IKDC score was 90.36%. Six months after the procedure 197 (92.49% of patients had good or excellent subjective postoperative clinical outcomes, while 14 (6.57% patients subjectively did not notice a significant improvement after the intervention, and 2 (0.93% patients had no subjective improvement after the partial medial meniscectomy at all. Conclusion. Arthroscopic partial medial meniscetomy is minimally invasive diagnostic and therapeutic procedure and in well selected cases is a method of choice for treatment of medial meniscus injuries when repair techniques are not a viable option. It has small rate of complications, low morbidity and fast rehabilitation.

  16. Hierarchical partial order ranking

    International Nuclear Information System (INIS)

    Carlsen, Lars

    2008-01-01

    Assessing the potential impact on environmental and human health from the production and use of chemicals or from polluted sites involves a multi-criteria evaluation scheme. A priori several parameters are to address, e.g., production tonnage, specific release scenarios, geographical and site-specific factors in addition to various substance dependent parameters. Further socio-economic factors may be taken into consideration. The number of parameters to be included may well appear to be prohibitive for developing a sensible model. The study introduces hierarchical partial order ranking (HPOR) that remedies this problem. By HPOR the original parameters are initially grouped based on their mutual connection and a set of meta-descriptors is derived representing the ranking corresponding to the single groups of descriptors, respectively. A second partial order ranking is carried out based on the meta-descriptors, the final ranking being disclosed though average ranks. An illustrative example on the prioritisation of polluted sites is given. - Hierarchical partial order ranking of polluted sites has been developed for prioritization based on a large number of parameters

  17. The wild tapered block bootstrap

    DEFF Research Database (Denmark)

    Hounyo, Ulrich

    In this paper, a new resampling procedure, called the wild tapered block bootstrap, is introduced as a means of calculating standard errors of estimators and constructing confidence regions for parameters based on dependent heterogeneous data. The method consists in tapering each overlapping block...... of the series first, the applying the standard wild bootstrap for independent and heteroscedastic distrbuted observations to overlapping tapered blocks in an appropriate way. Its perserves the favorable bias and mean squared error properties of the tapered block bootstrap, which is the state-of-the-art block......-order asymptotic validity of the tapered block bootstrap as well as the wild tapered block bootstrap approximation to the actual distribution of the sample mean is also established when data are assumed to satisfy a near epoch dependent condition. The consistency of the bootstrap variance estimator for the sample...

  18. Studies on microphase-separated structures of block copolymers by neutron reflectivity measurement

    International Nuclear Information System (INIS)

    Torikai, Naoya; Noda, Ichiro; Matsushita, Yushu; Karim, A.; Satija, S.K.; Han, C.C.; Ebisawa, Toru.

    1996-01-01

    Segmental distributions of block copolymer chains in lamellar microphase-separated structure and those of homopolymers in block copolymer/homopolymer blends also with lamellar structures were studied by neutron reflectivity measurements. It was revealed that polystyrene and poly(2-vinylpyridine) lamellae were alternately stacked within the thin films of pure block copolymers spin-coated on silicon wafers, and they were preferentially oriented along the direction parallel to film surface. Polystyrene lamella appeared at air surfaces of the films, while poly(2-vinylpyridine) lamella did on silicon surfaces. Segment distribution at lamellar interface was well described by an error function, and the width of the lamellar interface, defined by a full-width half-maximum value of interfacial profile, was estimated to be about 4.5 nm. Segments of block chains adjacent to the chemical junction points connecting different block chains were strongly localized near the lamellar interfaces, while those on the free ends of block chains were distributed all over the lamellar microdomains with their distribution maxima at the centers of lamellae. On the other hand, it was clarified that homopolymers dissolved in the corresponding lamellar microdomains of block copolymers were also distributed throughout the microdomains with their concentration maxima at the centers of the lamellae. (author)

  19. A segmentation approach for a delineation of terrestrial ecoregions

    Science.gov (United States)

    Nowosad, J.; Stepinski, T.

    2017-12-01

    Terrestrial ecoregions are the result of regionalization of land into homogeneous units of similar ecological and physiographic features. Terrestrial Ecoregions of the World (TEW) is a commonly used global ecoregionalization based on expert knowledge and in situ observations. Ecological Land Units (ELUs) is a global classification of 250 meters-sized cells into 4000 types on the basis of the categorical values of four environmental variables. ELUs are automatically calculated and reproducible but they are not a regionalization which makes them impractical for GIS-based spatial analysis and for comparison with TEW. We have regionalized terrestrial ecosystems on the basis of patterns of the same variables (land cover, soils, landform, and bioclimate) previously used in ELUs. Considering patterns of categorical variables makes segmentation and thus regionalization possible. Original raster datasets of the four variables are first transformed into regular grids of square-sized blocks of their cells called eco-sites. Eco-sites are elementary land units containing local patterns of physiographic characteristics and thus assumed to contain a single ecosystem. Next, eco-sites are locally aggregated using a procedure analogous to image segmentation. The procedure optimizes pattern homogeneity of all four environmental variables within each segment. The result is a regionalization of the landmass into land units characterized by uniform pattern of land cover, soils, landforms, climate, and, by inference, by uniform ecosystem. Because several disjoined segments may have very similar characteristics, we cluster the segments to obtain a smaller set of segment types which we identify with ecoregions. Our approach is automatic, reproducible, updatable, and customizable. It yields the first automatic delineation of ecoregions on the global scale. In the resulting vector database each ecoregion/segment is described by numerous attributes which make it a valuable GIS resource for

  20. The Hierarchy of Segment Reports

    Directory of Open Access Journals (Sweden)

    Danilo Dorović

    2015-05-01

    Full Text Available The article presents an attempt to find the connection between reports created for managers responsible for different business segments. With this purpose, the hierarchy of the business reporting segments is proposed. This can lead to better understanding of the expenses under common responsibility of more than one manager since these expenses should be in more than one report. The structure of cost defined per business segment hierarchy with the aim of new, unusual but relevant cost structure for management can be established. Both could potentially bring new information benefits for management in the context of profit reporting.

  1. Segmental dilatation of the ileum

    Directory of Open Access Journals (Sweden)

    Tune-Yie Shih

    2017-01-01

    Full Text Available A 2-year-old boy was sent to the emergency department with the chief problem of abdominal pain for 1 day. He was just discharged from the pediatric ward with the diagnosis of mycoplasmal pneumonia and paralytic ileus. After initial examinations and radiographic investigations, midgut volvulus was impressed. An emergency laparotomy was performed. Segmental dilatation of the ileum with volvulus was found. The operative procedure was resection of the dilated ileal segment with anastomosis. The postoperative recovery was uneventful. The unique abnormality of gastrointestinal tract – segmental dilatation of the ileum, is described in details and the literature is reviewed.

  2. Block-based wavelet transform coding of mammograms with region-adaptive quantization

    Science.gov (United States)

    Moon, Nam Su; Song, Jun S.; Kwon, Musik; Kim, JongHyo; Lee, ChoongWoong

    1998-06-01

    To achieve both high compression ratio and information preserving, it is an efficient way to combine segmentation and lossy compression scheme. Microcalcification in mammogram is one of the most significant sign of early stage of breast cancer. Therefore in coding, detection and segmentation of microcalcification enable us to preserve it well by allocating more bits to it than to other regions. Segmentation of microcalcification is performed both in spatial domain and in wavelet transform domain. Peak error controllable quantization step, which is off-line designed, is suitable for medical image compression. For region-adaptive quantization, block- based wavelet transform coding is adopted and different peak- error-constrained quantizers are applied to blocks according to the segmentation result. In view of preservation of microcalcification, the proposed coding scheme shows better performance than JPEG.

  3. Effect of Partial Replacement of Sand With Quarry Dust on the ...

    African Journals Online (AJOL)

    This work investigated the effect of partial replacement of sand with quarry dust on the compressive strength, flexural strength, split tensile strength and water absorption of sandcrete blocks. River sand was replaced with quarry dust at percentages ranging from 0 to 40 at cement/combined aggregate ratio of 1: 6. The blocks ...

  4. Random walks with statistical shape prior for cochlea and inner ear segmentation in micro-CT images

    DEFF Research Database (Denmark)

    Ruiz Pujadas, Esmeralda; Piella, Gemma; Kjer, Hans Martin

    2017-01-01

    A cochlear implant is an electronic device which can restore sound to completely or partially deaf patients. For surgical planning, a patient-specific model of the inner ear must be built using high-resolution images accurately segmented. We propose a new framework for segmentation of micro-CT...

  5. Accounting for segment correlations in segmented gamma-ray scans

    International Nuclear Information System (INIS)

    Sheppard, G.A.; Prettyman, T.H.; Piquette, E.C.

    1994-01-01

    In a typical segmented gamma-ray scanner (SGS), the detector's field of view is collimated so that a complete horizontal slice or segment of the desired thickness is visible. Ordinarily, the collimator is not deep enough to exclude gamma rays emitted from sample volumes above and below the segment aligned with the collimator. This can lead to assay biases, particularly for certain radioactive-material distributions. Another consequence of the collimator's low aspect ratio is that segment assays at the top and bottom of the sample are biased low because the detector's field of view is not filled. This effect is ordinarily countered by placing the sample on a low-Z pedestal and scanning one or more segment thicknesses below and above the sample. This takes extra time, however, We have investigated a number of techniques that both account for correlated segments and correct for end effects in SGS assays. Also, we have developed an algorithm that facilitates estimates of assay precision. Six calculation methods have been compared by evaluating the results of thousands of simulated, assays for three types of gamma-ray source distribution and ten masses. We will report on these computational studies and their experimental verification

  6. Photovoltaic building blocks

    DEFF Research Database (Denmark)

    Hanberg, Peter Jesper; Jørgensen, Anders Michael

    2014-01-01

    efficiency of about 15% for commercial Silicon solar cells there is still much to gain. DTU Danchip provides research facilities, equipment and expertise for the building blocks that comprises fabricating the efficient solar cell. In order to get more of the sun light into the device we provide thin film......Photovoltaics (PV), better known as solar cells, are now a common day sight on many rooftops in Denmark.The installed capacity of PV systems worldwide is growing exponentially1 and is the third most importantrenewable energy source today. The cost of PV is decreasing fast with ~10%/year but to make...... it directcompetitive with fossil energy sources a further reduction is needed. By increasing the efficiency of the solar cells one gain an advantage through the whole chain of cost. So that per produced Watt of power less material is spent, installation costs are lower, less area is used etc. With an average...

  7. Celiac ganglia block

    International Nuclear Information System (INIS)

    Akinci, Devrim; Akhan, Okan

    2005-01-01

    Pain occurs frequently in patients with advanced cancers. Tumors originating from upper abdominal viscera such as pancreas, stomach, duodenum, proximal small bowel, liver and biliary tract and from compressing enlarged lymph nodes can cause severe abdominal pain, which do not respond satisfactorily to medical treatment or radiotherapy. Percutaneous celiac ganglia block (CGB) can be performed with high success and low complication rates under imaging guidance to obtain pain relief in patients with upper abdominal malignancies. A significant relationship between pain relief and degree of tumoral celiac ganglia invasion according to CT features was described in the literature. Performing the procedure in the early grades of celiac ganglia invasion on CT can increase the effectiveness of the CGB, which is contrary to World Health Organization criteria stating that CGB must be performed in patients with advanced stage cancer. CGB may also be effectively performed in patients with chronic pancreatitis for pain palliation

  8. Atomic Basic Blocks

    Science.gov (United States)

    Scheler, Fabian; Mitzlaff, Martin; Schröder-Preikschat, Wolfgang

    Die Entscheidung, einen zeit- bzw. ereignisgesteuerten Ansatz für ein Echtzeitsystem zu verwenden, ist schwierig und sehr weitreichend. Weitreichend vor allem deshalb, weil diese beiden Ansätze mit äußerst unterschiedlichen Kontrollflussabstraktionen verknüpft sind, die eine spätere Migration zum anderen Paradigma sehr schwer oder gar unmöglich machen. Wir schlagen daher die Verwendung einer Zwischendarstellung vor, die unabhängig von der jeweils verwendeten Kontrollflussabstraktion ist. Für diesen Zweck verwenden wir auf Basisblöcken basierende Atomic Basic Blocks (ABB) und bauen darauf ein Werkzeug, den Real-Time Systems Compiler (RTSC) auf, der die Migration zwischen zeit- und ereignisgesteuerten Systemen unterstützt.

  9. What are Segments in Google Analytics

    Science.gov (United States)

    Segments find all sessions that meet a specific condition. You can then apply this segment to any report in Google Analytics (GA). Segments are a way of identifying sessions and users while filters identify specific events, like pageviews.

  10. Some Blocks from Heliopolis

    Directory of Open Access Journals (Sweden)

    dr.Nageh Omar

    2005-01-01

    Full Text Available These group of Architectural Fragments have been discovered during Excavations at Souq el – Khamees Site at the end of Mostorod Street in el – Matarya Area by the Supreme Council of Antiquities Mission Season 2003 and none published before . The Site of Excavations is Situated about 500 metres to the west Obelisk of the King Senusert I According to the inscriptions on the block (pl.1.a,fig.1 represents the coronation name of the king Senusret III, the fifth king of the twelfth dynasty within the cartouche .Through This recent discover and his Sphinx statue we Suggest that the king Senusret III built a shrine or Temple at Heliopols which was possibly a part of the great Temple of the universal God of Heliopolis . For block dating to the king Akhenaten and many monuments are discovered in Heliopolis at the same period emphasized that the king Akhenaten built temple for the god Aten in Heliopolis and through Studies about the king Akhenaten, we suggest that the king Akhenaten take his new principles from Heliopolis . The king Ramesses II mentioned from stela which discovered at Manshyt el- Sader, in the second horizontal line that he erected oblesk and some statues at the great Temple in Heliopolis , this recent Discover about Statue of the king Ramesses II emphasized site of excavations perhaps a shrine or open court from temple of the king Ramesses II at the great Temple in Heliopolis For nbt – htpt, we could show that the goddess Hathor take a forward position in Heliopolis and become the Lady of Hetepet in Heliopolis since Eighteenth dynasty at least

  11. Image segmentation by hierarchial agglomeration of polygons using ecological statistics

    Science.gov (United States)

    Prasad, Lakshman; Swaminarayan, Sriram

    2013-04-23

    A method for rapid hierarchical image segmentation based on perceptually driven contour completion and scene statistics is disclosed. The method begins with an initial fine-scale segmentation of an image, such as obtained by perceptual completion of partial contours into polygonal regions using region-contour correspondences established by Delaunay triangulation of edge pixels as implemented in VISTA. The resulting polygons are analyzed with respect to their size and color/intensity distributions and the structural properties of their boundaries. Statistical estimates of granularity of size, similarity of color, texture, and saliency of intervening boundaries are computed and formulated into logical (Boolean) predicates. The combined satisfiability of these Boolean predicates by a pair of adjacent polygons at a given segmentation level qualifies them for merging into a larger polygon representing a coarser, larger-scale feature of the pixel image and collectively obtains the next level of polygonal segments in a hierarchy of fine-to-coarse segmentations. The iterative application of this process precipitates textured regions as polygons with highly convolved boundaries and helps distinguish them from objects which typically have more regular boundaries. The method yields a multiscale decomposition of an image into constituent features that enjoy a hierarchical relationship with features at finer and coarser scales. This provides a traversable graph structure from which feature content and context in terms of other features can be derived, aiding in automated image understanding tasks. The method disclosed is highly efficient and can be used to decompose and analyze large images.

  12. Extended abstract: Partial row projection methods

    Energy Technology Data Exchange (ETDEWEB)

    Bramley, R.; Lee, Y. [Indiana Univ., Bloomington, IN (United States)

    1996-12-31

    Accelerated row projection (RP) algorithms for solving linear systems Ax = b are a class of iterative methods which in theory converge for any nonsingular matrix. RP methods are by definition ones that require finding the orthogonal projection of vectors onto the null space of block rows of the matrix. The Kaczmarz form, considered here because it has a better spectrum for iterative methods, has an iteration matrix that is the product of such projectors. Because straightforward Kaczmarz method converges slowly for practical problems, typically an outer CG acceleration is applied. Definiteness, symmetry, or localization of the eigenvalues, of the coefficient matrix is not required. In spite of this robustness, work has generally been limited to structured systems such as block tridiagonal matrices because unlike many iterative solvers, RP methods cannot be implemented by simply supplying a matrix-vector multiplication routine. Finding the orthogonal projection of vectors onto the null space of block rows of the matrix in practice requires accessing the actual entries in the matrix. This report introduces a new partial RP algorithm which retains advantages of the RP methods.

  13. CLG for Automatic Image Segmentation

    OpenAIRE

    Christo Ananth; S.Santhana Priya; S.Manisha; T.Ezhil Jothi; M.S.Ramasubhaeswari

    2017-01-01

    This paper proposes an automatic segmentation method which effectively combines Active Contour Model, Live Wire method and Graph Cut approach (CLG). The aim of Live wire method is to provide control to the user on segmentation process during execution. Active Contour Model provides a statistical model of object shape and appearance to a new image which are built during a training phase. In the graph cut technique, each pixel is represented as a node and the distance between those nodes is rep...

  14. Market segmentation, targeting and positioning

    OpenAIRE

    Camilleri, Mark Anthony

    2017-01-01

    Businesses may not be in a position to satisfy all of their customers, every time. It may prove difficult to meet the exact requirements of each individual customer. People do not have identical preferences, so rarely does one product completely satisfy everyone. Many companies may usually adopt a strategy that is known as target marketing. This strategy involves dividing the market into segments and developing products or services to these segments. A target marketing strategy is focused on ...

  15. Recognition Using Classification and Segmentation Scoring

    National Research Council Canada - National Science Library

    Kimball, Owen; Ostendorf, Mari; Rohlicek, Robin

    1992-01-01

    .... We describe an approach to connected word recognition that allows the use of segmental information through an explicit decomposition of the recognition criterion into classification and segmentation scoring...

  16. Partially ordered algebraic systems

    CERN Document Server

    Fuchs, Laszlo

    2011-01-01

    Originally published in an important series of books on pure and applied mathematics, this monograph by a distinguished mathematician explores a high-level area in algebra. It constitutes the first systematic summary of research concerning partially ordered groups, semigroups, rings, and fields. The self-contained treatment features numerous problems, complete proofs, a detailed bibliography, and indexes. It presumes some knowledge of abstract algebra, providing necessary background and references where appropriate. This inexpensive edition of a hard-to-find systematic survey will fill a gap i

  17. Infinite partial summations

    International Nuclear Information System (INIS)

    Sprung, D.W.L.

    1975-01-01

    This paper is a brief review of those aspects of the effective interaction problem that can be grouped under the heading of infinite partial summations of the perturbation series. After a brief mention of the classic examples of infinite summations, the author turns to the effective interaction problem for two extra core particles. Their direct interaction is summed to produce the G matrix, while their indirect interaction through the core is summed in a variety of ways under the heading of core polarization. (orig./WL) [de

  18. On universal partial words

    OpenAIRE

    Chen, Herman Z. Q.; Kitaev, Sergey; Mütze, Torsten; Sun, Brian Y.

    2016-01-01

    A universal word for a finite alphabet $A$ and some integer $n\\geq 1$ is a word over $A$ such that every word in $A^n$ appears exactly once as a subword (cyclically or linearly). It is well-known and easy to prove that universal words exist for any $A$ and $n$. In this work we initiate the systematic study of universal partial words. These are words that in addition to the letters from $A$ may contain an arbitrary number of occurrences of a special `joker' symbol $\\Diamond\

  19. Partial differential equations

    CERN Document Server

    Agranovich, M S

    2002-01-01

    Mark Vishik's Partial Differential Equations seminar held at Moscow State University was one of the world's leading seminars in PDEs for over 40 years. This book celebrates Vishik's eightieth birthday. It comprises new results and survey papers written by many renowned specialists who actively participated over the years in Vishik's seminars. Contributions include original developments and methods in PDEs and related fields, such as mathematical physics, tomography, and symplectic geometry. Papers discuss linear and nonlinear equations, particularly linear elliptic problems in angles and gener

  20. Partial differential equations

    CERN Document Server

    Levine, Harold

    1997-01-01

    The subject matter, partial differential equations (PDEs), has a long history (dating from the 18th century) and an active contemporary phase. An early phase (with a separate focus on taut string vibrations and heat flow through solid bodies) stimulated developments of great importance for mathematical analysis, such as a wider concept of functions and integration and the existence of trigonometric or Fourier series representations. The direct relevance of PDEs to all manner of mathematical, physical and technical problems continues. This book presents a reasonably broad introductory account of the subject, with due regard for analytical detail, applications and historical matters.

  1. Partial differential equations

    CERN Document Server

    Sloan, D; Süli, E

    2001-01-01

    /homepage/sac/cam/na2000/index.html7-Volume Set now available at special set price ! Over the second half of the 20th century the subject area loosely referred to as numerical analysis of partial differential equations (PDEs) has undergone unprecedented development. At its practical end, the vigorous growth and steady diversification of the field were stimulated by the demand for accurate and reliable tools for computational modelling in physical sciences and engineering, and by the rapid development of computer hardware and architecture. At the more theoretical end, the analytical insight in

  2. Elliptic partial differential equations

    CERN Document Server

    Han, Qing

    2011-01-01

    Elliptic Partial Differential Equations by Qing Han and FangHua Lin is one of the best textbooks I know. It is the perfect introduction to PDE. In 150 pages or so it covers an amazing amount of wonderful and extraordinary useful material. I have used it as a textbook at both graduate and undergraduate levels which is possible since it only requires very little background material yet it covers an enormous amount of material. In my opinion it is a must read for all interested in analysis and geometry, and for all of my own PhD students it is indeed just that. I cannot say enough good things abo

  3. Generalized Partial Volume

    DEFF Research Database (Denmark)

    Darkner, Sune; Sporring, Jon

    2011-01-01

    Mutual Information (MI) and normalized mutual information (NMI) are popular choices as similarity measure for multimodal image registration. Presently, one of two approaches is often used for estimating these measures: The Parzen Window (PW) and the Generalized Partial Volume (GPV). Their theoret...... of view as well as w.r.t. computational complexity. Finally, we present algorithms for both approaches for NMI which is comparable in speed to Sum of Squared Differences (SSD), and we illustrate the differences between PW and GPV on a number of registration examples....

  4. Seismotectonics of Bhutan: Evidence for segmentation of the Eastern Himalayas and link to foreland deformation

    Science.gov (United States)

    Diehl, Tobias; Singer, Julia; Hetényi, György; Grujic, Djordje; Clinton, John; Giardini, Domenico; Kissling, Edi; Gansser Working Group

    2017-08-01

    The instrumental record of Bhutan is characterized by a lower seismicity compared to other parts of the Himalayan arc. To understand this low activity and its impact on the seismic hazard, a seismic network was installed in Bhutan for 22 months between 2013 and 2014. Recorded seismicity, earthquake moment tensors and local earthquake tomography reveal along-strike variations in structure and crustal deformation regime. A thickened crust imaged in western Bhutan suggests lateral differences in stresses on the Main Himalayan Thrust (MHT), potentially affecting the interseismic coupling and deformation regime. Sikkim, western Bhutan and its foreland are characterized by strike-slip faulting in the Indian basement. Strain is particularly localized along a NW-SE striking mid-crustal fault zone reaching from Chungthang in northeast Sikkim to Dhubri at the northwestern edge of the Shillong Plateau in the foreland. The dextral Dhubri-Chungthang fault zone (DCF) causes segmentation of the Indian basement and the MHT between eastern Nepal and western Bhutan and connects the deformation front of the Himalaya with the Shillong Plateau by forming the western boundary of the Shillong block. The Kopili fault, the proposed eastern boundary of this block, appears to be a diffuse zone of mid-crustal seismicity in the foreland. In eastern Bhutan we image a seismogenic, flat portion of the MHT, which might be either related to a partially creeping segment or to increased background seismicity originating from the 2009 MW 6.1 earthquake. In western-central Bhutan clusters of micro-earthquakes at the front of the High-Himalayas indicate the presence of a mid-crustal ramp and stress buildup on a fully coupled MHT. The area bounded by the DCF in the west and the seismogenic MHT in the east has the potential for M7-8 earthquakes in Bhutan. Similarly, the DCF has the potential to host M7 earthquakes as documented by the 2011 Sikkim and the 1930 Dhubri earthquakes, which were potentially

  5. An improved method for pancreas segmentation using SLIC and interactive region merging

    Science.gov (United States)

    Zhang, Liyuan; Yang, Huamin; Shi, Weili; Miao, Yu; Li, Qingliang; He, Fei; He, Wei; Li, Yanfang; Zhang, Huimao; Mori, Kensaku; Jiang, Zhengang

    2017-03-01

    Considering the weak edges in pancreas segmentation, this paper proposes a new solution which integrates more features of CT images by combining SLIC superpixels and interactive region merging. In the proposed method, Mahalanobis distance is first utilized in SLIC method to generate better superpixel images. By extracting five texture features and one gray feature, the similarity measure between two superpixels becomes more reliable in interactive region merging. Furthermore, object edge blocks are accurately addressed by re-segmentation merging process. Applying the proposed method to four cases of abdominal CT images, we segment pancreatic tissues to verify the feasibility and effectiveness. The experimental results show that the proposed method can make segmentation accuracy increase to 92% on average. This study will boost the application process of pancreas segmentation for computer-aided diagnosis system.

  6. Scala vestibuli cochlear implantation in patients with partially ossified cochleas.

    Science.gov (United States)

    Berrettini, Stefano; Forli, Francesca; Neri, Emanuele; Segnini, Giovanni; Franceschini, Stefano Sellari

    2002-11-01

    Partial cochlear obstruction is a relatively common finding in candidates for cochlear implants and frequently involves the inferior segment of the scala tympani in the basal turn of the cochlea. In such patients, the scala vestibuli is often patent and offers an alternative site for implantation. The current report describes two patients with such partial obstruction of the inferior segment of the basal cochlear turn, caused in one case by systemic vasculitis (Takayasu's disease) and in the other by obliterative otosclerosis. A scala vestibuli implantation allowed for complete insertion of the electrode array. No problems were encountered during the surgical procedures and the good post-operative hearing and communicative outcomes achieved were similar to those reported in patients without cochlear ossification. The importance of accurate pre-operative radiological study of the inner ear is underscored, to disclose the presence and define the features of the cochlear ossification and ultimately to properly plan the surgical approach.

  7. Morphological studies on block copolymer modified PA 6 blends

    Energy Technology Data Exchange (ETDEWEB)

    Poindl, M., E-mail: marcus.poindl@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de; Bonten, C., E-mail: marcus.poindl@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de [Institut für Kunststofftechnik, University of Stuttgart (Germany)

    2014-05-15

    Recent studies show that compounding polyamide 6 (PA 6) with a PA 6 polyether block copolymers made by reaction injection molding (RIM) or continuous anionic polymerization in a reactive extrusion process (REX) result in blends with high impact strength and high stiffness compared to conventional rubber blends. In this paper, different high impact PA 6 blends were prepared using a twin screw extruder. The different impact modifiers were an ethylene propylene copolymer, a PA PA 6 polyether block copolymer made by reaction injection molding and one made by reactive extrusion. To ensure good particle matrix bonding, the ethylene propylene copolymer was grafted with maleic anhydride (EPR-g-MA). Due to the molecular structure of the two block copolymers, a coupling agent was not necessary. The block copolymers are semi-crystalline and partially cross-linked in contrast to commonly used amorphous rubbers which are usually uncured. The combination of different analysis methods like atomic force microscopy (AFM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) gave a detailed view in the structure of the blends. Due to the partial cross-linking, the particles of the block copolymers in the blends are not spherical like the ones of ethylene propylene copolymer. The differences in molecular structure, miscibility and grafting of the impact modifiers result in different mechanical properties and different blend morphologies.

  8. Segmentation of Handwritten Chinese Character Strings Based on improved Algorithm Liu

    Directory of Open Access Journals (Sweden)

    Zhihua Cai

    2014-09-01

    Full Text Available Algorithm Liu attracts high attention because of its high accuracy in segmentation of Japanese postal address. But the disadvantages, such as complexity and difficult implementation of algorithm, etc. have an adverse effect on its popularization and application. In this paper, the author applies the principles of algorithm Liu to handwritten Chinese character segmentation according to the characteristics of the handwritten Chinese characters, based on deeply study on algorithm Liu.In the same time, the author put forward the judgment criterion of Segmentation block classification and adhering mode of the handwritten Chinese characters.In the process of segmentation, text images are seen as the sequence made up of Connected Components (CCs, while the connected components are made up of several horizontal itinerary set of black pixels in image. The author determines whether these parts will be merged into segmentation through analyzing connected components. And then the author does image segmentation through adhering mode based on the analysis of outline edges. Finally cut the text images into character segmentation. Experimental results show that the improved Algorithm Liu obtains high segmentation accuracy and produces a satisfactory segmentation result.

  9. Two-Segment Foot Model for the Biomechanical Analysis of Squat

    OpenAIRE

    Panero, E.; Gastaldi, L.; Rapp, W.

    2017-01-01

    Squat exercise is acquiring interest in many fields, due to its benefits in improving health and its biomechanical similarities to a wide range of sport motions and the recruitment of many body segments in a single maneuver. Several researches had examined considerable biomechanical aspects of lower limbs during squat, but not without limitations. The main goal of this study focuses on the analysis of the foot contribution during a partial body weight squat, using a two-segment foot model tha...

  10. Unilateral removable partial dentures.

    Science.gov (United States)

    Goodall, W A; Greer, A C; Martin, N

    2017-01-27

    Removable partial dentures (RPDs) are widely used to replace missing teeth in order to restore both function and aesthetics for the partially dentate patient. Conventional RPD design is frequently bilateral and consists of a major connector that bridges both sides of the arch. Some patients cannot and will not tolerate such an extensive appliance. For these patients, bridgework may not be a predictable option and it is not always possible to provide implant-retained restorations. This article presents unilateral RPDs as a potential treatment modality for such patients and explores indications and contraindications for their use, including factors relating to patient history, clinical presentation and patient wishes. Through case examples, design, material and fabrication considerations will be discussed. While their use is not widespread, there are a number of patients who benefit from the provision of unilateral RPDs. They are a useful treatment to have in the clinician's armamentarium, but a highly-skilled dental team and a specific patient presentation is required in order for them to be a reasonable and predictable prosthetic option.

  11. Quantum Partial Searching Algorithm of a Database with Several Target Items

    International Nuclear Information System (INIS)

    Pu-Cha, Zhong; Wan-Su, Bao; Yun, Wei

    2009-01-01

    Choi and Korepin [Quantum Information Processing 6(2007)243] presented a quantum partial search algorithm of a database with several target items which can find a target block quickly when each target block contains the same number of target items. Actually, the number of target items in each target block is arbitrary. Aiming at this case, we give a condition to guarantee performance of the partial search algorithm to be performed and the number of queries to oracle of the algorithm to be minimized. In addition, by further numerical computing we come to the conclusion that the more uniform the distribution of target items, the smaller the number of queries

  12. Common blocks for ASQS(12

    Directory of Open Access Journals (Sweden)

    Lorenzo Milazzo

    1997-05-01

    Full Text Available An ASQS(v is a particular Steiner system featuring a set of v vertices and two separate families of blocks, B and G, whose elements have a respective cardinality of 4 and 6. It has the property that any three vertices of X belong either to a B-block or to a G-block. The parameter cb is the number of common blocks in two separate ASQSs, both defined on the same set of vertices X . In this paper it is shown that cb ≤ 29 for any pair of ASQSs(12.

  13. Clean drinking water as a sustainable development goal: Fair, universal access with increasing block tariffs

    OpenAIRE

    von Hirschhausen, Christian; Flekstad, Maya; Meran, Georg

    2017-01-01

    One focus of the G20 Summit in Hamburg in July 2017 was the United Nations' sustainable development goals, including those set for the water sector. Despite progress, around 800 million people worldwide do not have adequate access to drinking water. Increasing block tariffs are an instrument widely used to support access to drinking water for poorer segments of the population. With this system, the price of water progressively increases with the volume consumed. An affordable first block ensu...

  14. Thermal stress analysis of HTGR fuel and control rod fuel blocks in the HTGR in-block carbonization and annealing furnace

    International Nuclear Information System (INIS)

    Gwaltney, R.C.; McAfee, W.J.

    1977-01-01

    A new approach that utilizes the equivalent solid plate method has been applied to the thermal stress analysis of HTGR fuel and control rod fuel blocks. Cases were considered where these blocks, loaded with reprocessed HTGR fuel pellets, were being cured at temperatures up to 1800 0 C. A two-dimensional segment of a fuel block cross section including fuel, coolant holes, and graphite matrix was analyzed using the ORNL HEATING3 heat transfer code to determine the temperature-dependent effective thermal conductivity for the perforated region of the block. Using this equivalent conductivity to calculate the temperature distributions through different cross sections of the blocks, two-dimensional thermal-stress analyses were performed through application of the equivalent solid plate method. In this approach, the perforated material is replaced by solid homogeneous material of the same external dimensions but whose material properties have been modified to account for the perforations

  15. Adductor Canal Block versus Femoral Nerve Block and Quadriceps Strength

    DEFF Research Database (Denmark)

    Jæger, Pia Therese; Nielsen, Zbigniew Jerzy Koscielniak; Henningsen, Lene Marianne

    2013-01-01

    : The authors hypothesized that the adductor canal block (ACB), a predominant sensory blockade, reduces quadriceps strength compared with placebo (primary endpoint, area under the curve, 0.5-6 h), but less than the femoral nerve block (FNB; secondary endpoint). Other secondary endpoints were...

  16. Tutorial on Online Partial Evaluation

    Directory of Open Access Journals (Sweden)

    William R. Cook

    2011-09-01

    Full Text Available This paper is a short tutorial introduction to online partial evaluation. We show how to write a simple online partial evaluator for a simple, pure, first-order, functional programming language. In particular, we show that the partial evaluator can be derived as a variation on a compositionally defined interpreter. We demonstrate the use of the resulting partial evaluator for program optimization in the context of model-driven development.

  17. The block transfer system

    International Nuclear Information System (INIS)

    Bradish, G.J. III; Reid, A.E.

    1986-01-01

    The central instrumentation control and data acquisition (CICADA) computer system is comprised of a functionally distributed hierarchical network of thirteen (13) 32-bit mini-computers that are the heart of the control, monitoring, data collection and data analysis for the tokamak fusion test reactor (TFTR). The CICADA system was designed with the goal of providing complete control, monitoring, and data acquisition for TFTR, which includes the acquisition and storage of 20M points of data within a five-minute shot cycle. It was realized early in the system design that in order to meet this goal an ancillary system would have to be provided to supplement the subsystem CAMAC systems that, due to the relatively slow throughput of the serial highways and the overhead of relaying data to the central facilities within a star network, would not provide the necessary throughput. The authors discuss how the block transfer system provided a means of moving data directly from the CAMAC crate to the application running on the central facility computers

  18. Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML...

  19. Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML of ...

  20. Methods of evaluating segmentation characteristics and segmentation of major faults

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kie Hwa; Chang, Tae Woo; Kyung, Jai Bok [Seoul National Univ., Seoul (Korea, Republic of)] (and others)

    2000-03-15

    Seismological, geological, and geophysical studies were made for reasonable segmentation of the Ulsan fault and the results are as follows. One- and two- dimensional electrical surveys revealed clearly the fault fracture zone enlarges systematically northward and southward from the vicinity of Mohwa-ri, indicating Mohwa-ri is at the seismic segment boundary. Field Geological survey and microscope observation of fault gouge indicates that the Quaternary faults in the area are reactivated products of the preexisting faults. Trench survey of the Chonbuk fault Galgok-ri revealed thrust faults and cumulative vertical displacement due to faulting during the late Quaternary with about 1.1-1.9 m displacement per event; the latest event occurred from 14000 to 25000 yrs. BP. The seismic survey showed the basement surface os cut by numerous reverse faults and indicated the possibility that the boundary between Kyeongsangbukdo and Kyeongsannamdo may be segment boundary.

  1. Segmentation by Large Scale Hypothesis Testing - Segmentation as Outlier Detection

    DEFF Research Database (Denmark)

    Darkner, Sune; Dahl, Anders Lindbjerg; Larsen, Rasmus

    2010-01-01

    a microscope and we show how the method can handle transparent particles with significant glare point. The method generalizes to other problems. THis is illustrated by applying the method to camera calibration images and MRI of the midsagittal plane for gray and white matter separation and segmentation......We propose a novel and efficient way of performing local image segmentation. For many applications a threshold of pixel intensities is sufficient but determine the appropriate threshold value can be difficult. In cases with large global intensity variation the threshold value has to be adapted...... locally. We propose a method based on large scale hypothesis testing with a consistent method for selecting an appropriate threshold for the given data. By estimating the background distribution we characterize the segment of interest as a set of outliers with a certain probability based on the estimated...

  2. Methods of evaluating segmentation characteristics and segmentation of major faults

    International Nuclear Information System (INIS)

    Lee, Kie Hwa; Chang, Tae Woo; Kyung, Jai Bok

    2000-03-01

    Seismological, geological, and geophysical studies were made for reasonable segmentation of the Ulsan fault and the results are as follows. One- and two- dimensional electrical surveys revealed clearly the fault fracture zone enlarges systematically northward and southward from the vicinity of Mohwa-ri, indicating Mohwa-ri is at the seismic segment boundary. Field Geological survey and microscope observation of fault gouge indicates that the Quaternary faults in the area are reactivated products of the preexisting faults. Trench survey of the Chonbuk fault Galgok-ri revealed thrust faults and cumulative vertical displacement due to faulting during the late Quaternary with about 1.1-1.9 m displacement per event; the latest event occurred from 14000 to 25000 yrs. BP. The seismic survey showed the basement surface os cut by numerous reverse faults and indicated the possibility that the boundary between Kyeongsangbukdo and Kyeongsannamdo may be segment boundary

  3. Applied partial differential equations

    CERN Document Server

    Logan, J David

    2004-01-01

    This primer on elementary partial differential equations presents the standard material usually covered in a one-semester, undergraduate course on boundary value problems and PDEs. What makes this book unique is that it is a brief treatment, yet it covers all the major ideas: the wave equation, the diffusion equation, the Laplace equation, and the advection equation on bounded and unbounded domains. Methods include eigenfunction expansions, integral transforms, and characteristics. Mathematical ideas are motivated from physical problems, and the exposition is presented in a concise style accessible to science and engineering students; emphasis is on motivation, concepts, methods, and interpretation, rather than formal theory. This second edition contains new and additional exercises, and it includes a new chapter on the applications of PDEs to biology: age structured models, pattern formation; epidemic wave fronts, and advection-diffusion processes. The student who reads through this book and solves many of t...

  4. Inductance loop and partial

    CERN Document Server

    Paul, Clayton R

    2010-01-01

    "Inductance is an unprecedented text, thoroughly discussing "loop" inductance as well as the increasingly important "partial" inductance. These concepts and their proper calculation are crucial in designing modern high-speed digital systems. World-renowned leader in electromagnetics Clayton Paul provides the knowledge and tools necessary to understand and calculate inductance." "With the present and increasing emphasis on high-speed digital systems and high-frequency analog systems, it is imperative that system designers develop an intimate understanding of the concepts and methods in this book. Inductance is a much-needed textbook designed for senior and graduate-level engineering students, as well as a hands-on guide for working engineers and professionals engaged in the design of high-speed digital and high-frequency analog systems."--Jacket.

  5. Fundamental partial compositeness

    CERN Document Server

    Sannino, Francesco

    2016-11-07

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Successful models exist because gauge quantum numbers of Standard Model fermions admit a minimal enough 'square root'. Furthermore, right-handed SM fermions have an SU(2)$_R$-like structure, yielding a custodially-protected composite Higgs. Baryon and lepton numbers arise accidentally. Standard Model fermions acquire mass at tree level, while the Higgs potential and flavor violations are generated by quantum corrections. We further discuss accidental symmetries and other dynamical features stemming from the new strongly interacting scalars. If the same phenomenology can be obtained from models without our elementary scalars, they would reappear as composite states.

  6. Fundamental partial compositeness

    International Nuclear Information System (INIS)

    Sannino, Francesco; Strumia, Alessandro; Tesi, Andrea; Vigiani, Elena

    2016-01-01

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Under certain assumptions on the dynamics of the scalars, successful models exist because gauge quantum numbers of Standard Model fermions admit a minimal enough ‘square root’. Furthermore, right-handed SM fermions have an SU(2)_R-like structure, yielding a custodially-protected composite Higgs. Baryon and lepton numbers arise accidentally. Standard Model fermions acquire mass at tree level, while the Higgs potential and flavor violations are generated by quantum corrections. We further discuss accidental symmetries and other dynamical features stemming from the new strongly interacting scalars. If the same phenomenology can be obtained from models without our elementary scalars, they would reappear as composite states.

  7. Evaluation of partial beta-adrenoceptor agonist activity.

    Science.gov (United States)

    Lipworth, B J; Grove, A

    1997-01-01

    A partial beta-adrenoceptor (beta-AR) agonist will exhibit opposite agonist and antagonist activity depending on the prevailing degree of adrenergic tone or the presence of a beta-AR agonist with higher intrinsic activity. In vivo partial beta-AR agonist activity will be evident at rest with low endogenous adrenergic tone, as for example with chronotropicity (beta 1/beta 2), inotropicity (beta 1) or peripheral vasodilatation and finger tremor (beta 2). beta-AR blocking drugs which have partial agonist activity may exhibit a better therapeutic profile when used for hypertension because of maintained cardiac output without increased systemic vascular resistance, along with an improved lipid profile. In the presence of raised endogenous adrenergic tone such as exercise or an exogenous full agonist, beta-AR subtype antagonist activity will become evident in terms of effects on exercise induced heart rate (beta 1) and potassium (beta 2) responses. Reduction of exercise heart rate will occur to a lesser degree in the case of a beta-adrenoceptor blocker with partial beta 1-AR agonist activity compared with a beta-adrenoceptor blocker devoid of partial agonist activity. This may result in reduced therapeutic efficacy in the treatment of angina on effort when using beta-AR blocking drugs with partial beta 1-AR agonist activity. Effects on exercise hyperkalaemia are determined by the balance between beta 2-AR partial agonist activity and endogenous adrenergic activity. For predominantly beta 2-AR agonist such as salmeterol and salbutamol, potentiation of exercise hyperkalaemia occurs. For predominantly beta 2-AR antagonists such as carteolol, either potentiation or attenuation of exercise hyperkalaemia occurs at low and high doses respectively. beta 2-AR partial agonist activity may also be expressed as antagonism in the presence of an exogenous full agonist, as for example attenuation of fenoterol induced responses by salmeterol. Studies are required to investigate whether

  8. Automatic segmentation of psoriasis lesions

    Science.gov (United States)

    Ning, Yang; Shi, Chenbo; Wang, Li; Shu, Chang

    2014-10-01

    The automatic segmentation of psoriatic lesions is widely researched these years. It is an important step in Computer-aid methods of calculating PASI for estimation of lesions. Currently those algorithms can only handle single erythema or only deal with scaling segmentation. In practice, scaling and erythema are often mixed together. In order to get the segmentation of lesions area - this paper proposes an algorithm based on Random forests with color and texture features. The algorithm has three steps. The first step, the polarized light is applied based on the skin's Tyndall-effect in the imaging to eliminate the reflection and Lab color space are used for fitting the human perception. The second step, sliding window and its sub windows are used to get textural feature and color feature. In this step, a feature of image roughness has been defined, so that scaling can be easily separated from normal skin. In the end, Random forests will be used to ensure the generalization ability of the algorithm. This algorithm can give reliable segmentation results even the image has different lighting conditions, skin types. In the data set offered by Union Hospital, more than 90% images can be segmented accurately.

  9. Partial oxidation process

    International Nuclear Information System (INIS)

    Najjar, M.S.

    1987-01-01

    A process is described for the production of gaseous mixtures comprising H/sub 2/+CO by the partial oxidation of a fuel feedstock comprising a heavy liquid hydrocarbonaceous fuel having a nickel, iron, and vanadium-containing ash or petroleum coke having a nickel, iron, and vanadium-containing ash, or mixtures thereof. The feedstock includes a minimum of 0.5 wt. % of sulfur and the ash includes a minimum of 5.0 wt. % vanadium, a minimum of 0.5 ppm nickel, and a minimum of 0.5 ppm iron. The process comprises: (1) mixing together a copper-containing additive with the fuel feedstock; wherein the weight ratio of copper-containing additive to ash in the fuel feedstock is in the range of about 1.0-10.0, and there is at least 10 parts by weight of copper for each part by weight of vanadium; (2) reacting the mixture from (1) at a temperature in the range of 2200 0 F to 2900 0 F and a pressure in the range of about 5 to 250 atmospheres in a free-flow refactory lined partial oxidation reaction zone with a free-oxygen containing gas in the presence of a temperature moderator and in a reducing atmosphere to produce a hot raw effluent gas stream comprising H/sub 2/+CO and entrained molten slag; and where in the reaction zone and the copper-containing additive combines with at least a portion of the nickel and iron constituents and sulfur found in the feedstock to produce a liquid phase washing agent that collects and transports at least a portion of the vanadium-containing oxide laths and spinels and other ash components and refractory out of the reaction zone; and (3) separating nongaseous materials from the hot raw effluent gas stream

  10. Microsurgical replantation and postoperative leech treatment of a large severed nasal segment

    DEFF Research Database (Denmark)

    Stemann Andersen, Peter; Elberg, Jens Jørgen

    2012-01-01

    The survival of a microsurgically replanted segment of nose in a 41-year-old woman was facilitated by the assistance of the medicinal leech Hirudo medicinalis. An arterial microanastomosis was made to a severed partial segment of nose with no possibility of recreating a venous anastomosis. The re....... The resulting venous congestion was treated with nine days of treatment with a medical leech until venous neovascularisation had been achieved. At follow-up six months after discharge there was a well-heeled nasal segment and a satisfying functional - as well as cosmetic - result....

  11. Shape-tailored local descriptors and their application to segmentation and tracking

    KAUST Repository

    Khan, Naeemullah; Algarni, Marei Saeed Mohammed; Yezzi, Anthony; Sundaramoorthi, Ganesh

    2015-01-01

    We propose new dense descriptors for texture segmentation. Given a region of arbitrary shape in an image, these descriptors are formed from shape-dependent scale spaces of oriented gradients. These scale spaces are defined by Poisson-like partial differential equations. A key property of our new descriptors is that they do not aggregate image data across the boundary of the region, in contrast to existing descriptors based on aggregation of oriented gradients. As an example, we show how the descriptor can be incorporated in a Mumford-Shah energy for texture segmentation. We test our method on several challenging datasets for texture segmentation and textured object tracking. Experiments indicate that our descriptors lead to more accurate segmentation than non-shape dependent descriptors and the state-of-the-art in texture segmentation.

  12. Shape-tailored local descriptors and their application to segmentation and tracking

    KAUST Repository

    Khan, Naeemullah

    2015-06-07

    We propose new dense descriptors for texture segmentation. Given a region of arbitrary shape in an image, these descriptors are formed from shape-dependent scale spaces of oriented gradients. These scale spaces are defined by Poisson-like partial differential equations. A key property of our new descriptors is that they do not aggregate image data across the boundary of the region, in contrast to existing descriptors based on aggregation of oriented gradients. As an example, we show how the descriptor can be incorporated in a Mumford-Shah energy for texture segmentation. We test our method on several challenging datasets for texture segmentation and textured object tracking. Experiments indicate that our descriptors lead to more accurate segmentation than non-shape dependent descriptors and the state-of-the-art in texture segmentation.

  13. Skip segment Hirschsprung disease and Waardenburg syndrome

    Directory of Open Access Journals (Sweden)

    Erica R. Gross

    2015-04-01

    Full Text Available Skip segment Hirschsprung disease describes a segment of ganglionated bowel between two segments of aganglionated bowel. It is a rare phenomenon that is difficult to diagnose. We describe a recent case of skip segment Hirschsprung disease in a neonate with a family history of Waardenburg syndrome and the genetic profile that was identified.

  14. U.S. Army Custom Segmentation System

    Science.gov (United States)

    2007-06-01

    segmentation is individual or intergroup differences in response to marketing - mix variables. Presumptions about segments: •different demands in a...product or service category, •respond differently to changes in the marketing mix Criteria for segments: •The segments must exist in the environment

  15. Skip segment Hirschsprung disease and Waardenburg syndrome

    OpenAIRE

    Gross, Erica R.; Geddes, Gabrielle C.; McCarrier, Julie A.; Jarzembowski, Jason A.; Arca, Marjorie J.

    2015-01-01

    Skip segment Hirschsprung disease describes a segment of ganglionated bowel between two segments of aganglionated bowel. It is a rare phenomenon that is difficult to diagnose. We describe a recent case of skip segment Hirschsprung disease in a neonate with a family history of Waardenburg syndrome and the genetic profile that was identified.

  16. OPAL Various Lead Glass Blocks

    CERN Multimedia

    These lead glass blocks were part of a CERN detector called OPAL (one of the four experiments at the LEP particle detector). OPAL uses some 12 000 blocks of glass like this to measure particle energies in the electromagnetic calorimeter. This detector measured the energy deposited when electrons and photons were slowed down and stopped.

  17. Writing Blocks and Tacit Knowledge.

    Science.gov (United States)

    Boice, Robert

    1993-01-01

    A review of the literature on writing block looks at two kinds: inability to write in a timely, fluent fashion, and reluctance by academicians to assist others in writing. Obstacles to fluent writing are outlined, four historical trends in treating blocks are discussed, and implications are examined. (MSE)

  18. Block storage subsystem performance analysis

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    You feel that your service is slow because of the storage subsystem? But there are too many abstraction layers between your software and the raw block device for you to debug all this pile... Let's dive on the platters and check out how the block storage sees your I/Os! We can even figure out what those patterns are meaning.

  19. Region 9 Census Block 2010

    Science.gov (United States)

    Geography:The TIGER Line Files are feature classes and related database files (.) that are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER Line File is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Census Blocks are statistical areas bounded on all sides by visible features, such as streets, roads, streams, and railroad tracks, and/or by non visible boundaries such as city, town, township, and county limits, and short line-of-sight extensions of streets and roads. Census blocks are relatively small in area; for example, a block in a city bounded by streets. However, census blocks in remote areas are often large and irregular and may even be many square miles in area. A common misunderstanding is that data users think census blocks are used geographically to build all other census geographic areas, rather all other census geographic areas are updated and then used as the primary constraints, along with roads and water features, to delineate the tabulation blocks. As a result, all 2010 Census blocks nest within every other 2010 Census geographic area, so that Census Bureau statistical data can be tabulated at the block level and aggregated up t

  20. Selecting salient frames for spatiotemporal video modeling and segmentation.

    Science.gov (United States)

    Song, Xiaomu; Fan, Guoliang

    2007-12-01

    We propose a new statistical generative model for spatiotemporal video segmentation. The objective is to partition a video sequence into homogeneous segments that can be used as "building blocks" for semantic video segmentation. The baseline framework is a Gaussian mixture model (GMM)-based video modeling approach that involves a six-dimensional spatiotemporal feature space. Specifically, we introduce the concept of frame saliency to quantify the relevancy of a video frame to the GMM-based spatiotemporal video modeling. This helps us use a small set of salient frames to facilitate the model training by reducing data redundancy and irrelevance. A modified expectation maximization algorithm is developed for simultaneous GMM training and frame saliency estimation, and the frames with the highest saliency values are extracted to refine the GMM estimation for video segmentation. Moreover, it is interesting to find that frame saliency can imply some object behaviors. This makes the proposed method also applicable to other frame-related video analysis tasks, such as key-frame extraction, video skimming, etc. Experiments on real videos demonstrate the effectiveness and efficiency of the proposed method.

  1. REVIEW ON HARD SEGMENT INFLUENCESON THE PHYSICALPROPERTIES OF THERMOPLASTICPOLYURETHANES

    Directory of Open Access Journals (Sweden)

    Nurul Hidayati Fithriyah

    2012-04-01

    Full Text Available Thermoplastic polyurethanes (TPUs are the fastest growing market in polyurethane technology mainly due to their easy process ability, versatile properties and recyclable nature. They find applications in high performance materials like coatings, adhesives, fibres and foams in a variety of industries ranging from automotive and footwear to medical implants. TPUs are linear block copolymers comprising of alternating soft and hard segments. The versatile properties of TPUs are usually attributed to their phase-separated morphologies. Different parameters are known to affect TPUs physical properties. One of those is their chemical architecture that is the statistical arrangement of hard segments (HS and soft segments (SS.In particular the architecture of the HS will influence the molecular structure and intermolecular interaction. Its role as physical crosslink sites will govern thermal, mechanical and morphological properties. Hence a modification of HS chemical architecture might adjust the ultimate properties of TPU. This implication is important in process control of production and design of application. Therefore this paper will review various studies to understand the effect of different architecture to the properties of TPU.   Keywords: thermoplasticpolyurethanes, hard segment architecture, physical properties

  2. Detection of white spot lesions by segmenting laser speckle images using computer vision methods.

    Science.gov (United States)

    Gavinho, Luciano G; Araujo, Sidnei A; Bussadori, Sandra K; Silva, João V P; Deana, Alessandro M

    2018-05-05

    This paper aims to develop a method for laser speckle image segmentation of tooth surfaces for diagnosis of early stages caries. The method, applied directly to a raw image obtained by digital photography, is based on the difference between the speckle pattern of a carious lesion tooth surface area and that of a sound area. Each image is divided into blocks which are identified in a working matrix by their χ 2 distance between block histograms of the analyzed image and the reference histograms previously obtained by K-means from healthy (h_Sound) and lesioned (h_Decay) areas, separately. If the χ 2 distance between a block histogram and h_Sound is greater than the distance to h_Decay, this block is marked as decayed. The experiments showed that the method can provide effective segmentation for initial lesions. We used 64 images to test the algorithm and we achieved 100% accuracy in segmentation. Differences between the speckle pattern of a sound tooth surface region and a carious region, even in the early stage, can be evidenced by the χ 2 distance between histograms. This method proves to be more effective for segmenting the laser speckle image, which enhances the contrast between sound and lesioned tissues. The results were obtained with low computational cost. The method has the potential for early diagnosis in a clinical environment, through the development of low-cost portable equipment.

  3. Tsunami impact to Washington and northern Oregon from segment ruptures on the southern Cascadia subduction zone

    Science.gov (United States)

    Priest, George R.; Zhang, Yinglong; Witter, Robert C.; Wang, Kelin; Goldfinger, Chris; Stimely, Laura

    2014-01-01

    This paper explores the size and arrival of tsunamis in Oregon and Washington from the most likely partial ruptures of the Cascadia subduction zone (CSZ) in order to determine (1) how quickly tsunami height declines away from sources, (2) evacuation time before significant inundation, and (3) extent of felt shaking that would trigger evacuation. According to interpretations of offshore turbidite deposits, the most frequent partial ruptures are of the southern CSZ. Combined recurrence of ruptures extending ~490 km from Cape Mendocino, California, to Waldport, Oregon (segment C) and ~320 km from Cape Mendocino to Cape Blanco, Oregon (segment D), is ~530 years. This recurrence is similar to frequency of full-margin ruptures on the CSZ inferred from paleoseismic data and to frequency of the largest distant tsunami sources threatening Washington and Oregon, ~Mw 9.2 earthquakes from the Gulf of Alaska. Simulated segment C and D ruptures produce relatively low-amplitude tsunamis north of source areas, even for extreme (20 m) peak slip on segment C. More than ~70 km north of segments C and D, the first tsunami arrival at the 10-m water depth has an amplitude of earthquake. MM V–VI shaking could trigger evacuation of educated populaces as far north as Newport, Oregon for segment D events and Grays Harbor, Washington for segment C events. The NOAA and local warning systems will be the only warning at greater distances from sources.

  4. A Novel Iris Segmentation Scheme

    Directory of Open Access Journals (Sweden)

    Chen-Chung Liu

    2014-01-01

    Full Text Available One of the key steps in the iris recognition system is the accurate iris segmentation from its surrounding noises including pupil, sclera, eyelashes, and eyebrows of a captured eye-image. This paper presents a novel iris segmentation scheme which utilizes the orientation matching transform to outline the outer and inner iris boundaries initially. It then employs Delogne-Kåsa circle fitting (instead of the traditional Hough transform to further eliminate the outlier points to extract a more precise iris area from an eye-image. In the extracted iris region, the proposed scheme further utilizes the differences in the intensity and positional characteristics of the iris, eyelid, and eyelashes to detect and delete these noises. The scheme is then applied on iris image database, UBIRIS.v1. The experimental results show that the presented scheme provides a more effective and efficient iris segmentation than other conventional methods.

  5. Results of the mock-up experiment on partial LOCA

    International Nuclear Information System (INIS)

    Dreier, J.; Winkler, H.

    1985-01-01

    A mockup experiment has been performed to verify the heat transfer model for a partial loss of coolant accident in the swimming pool reactor SAPHIR. Three coolant channels with the same dimensions as in a SAPHIR fuel element were simulated using four electrically heated plates. For a water level such that the heated plates are partially submerged, plate temperatures remain below 160 deg. C for plate powers of up to 650 W. For water levels low enough to just block the channels, plate temperatures of 400 deg. C are reached for plate powers as low as 60 W. Details of the experiment and further results are discussed. (author)

  6. Results of the mockup experiment on partial LOCA

    International Nuclear Information System (INIS)

    Dreier, J.; Winkler, H.

    1985-01-01

    A mockup experiment has been performed to verify the heat transfer model for a partial loss of coolant accident in the swimming pool reactor SAPHIR. Three coolant channels with the same dimensions as in a SAPHIR fuel element were simulated using four electrically heated plates. For a water level such that the heated plates are partially submerged, plate temperatures remain below 160 0 C for plate powers of up to 650 W. For water levels low enough to just block the channels, plate temperatures of 400 0 C are reached for plate powers as low as 60 W. Details of the experiment and further results are discussed

  7. LETTER TO THE EDITOR: Optimization of partial search

    Science.gov (United States)

    Korepin, Vladimir E.

    2005-11-01

    A quantum Grover search algorithm can find a target item in a database faster than any classical algorithm. One can trade accuracy for speed and find a part of the database (a block) containing the target item even faster; this is partial search. A partial search algorithm was recently suggested by Grover and Radhakrishnan. Here we optimize it. Efficiency of the search algorithm is measured by the number of queries to the oracle. The author suggests a new version of the Grover-Radhakrishnan algorithm which uses a minimal number of such queries. The algorithm can run on the same hardware that is used for the usual Grover algorithm.

  8. Document segmentation via oblique cuts

    Science.gov (United States)

    Svendsen, Jeremy; Branzan-Albu, Alexandra

    2013-01-01

    This paper presents a novel solution for the layout segmentation of graphical elements in Business Intelligence documents. We propose a generalization of the recursive X-Y cut algorithm, which allows for cutting along arbitrary oblique directions. An intermediate processing step consisting of line and solid region removal is also necessary due to presence of decorative elements. The output of the proposed segmentation is a hierarchical structure which allows for the identification of primitives in pie and bar charts. The algorithm was tested on a database composed of charts from business documents. Results are very promising.

  9. Optimally segmented permanent magnet structures

    DEFF Research Database (Denmark)

    Insinga, Andrea Roberto; Bjørk, Rasmus; Smith, Anders

    2016-01-01

    We present an optimization approach which can be employed to calculate the globally optimal segmentation of a two-dimensional magnetic system into uniformly magnetized pieces. For each segment the algorithm calculates the optimal shape and the optimal direction of the remanent flux density vector......, with respect to a linear objective functional. We illustrate the approach with results for magnet design problems from different areas, such as a permanent magnet electric motor, a beam focusing quadrupole magnet for particle accelerators and a rotary device for magnetic refrigeration....

  10. Intercalary bone segment transport in treatment of segmental tibial defects

    International Nuclear Information System (INIS)

    Iqbal, A.; Amin, M.S.

    2002-01-01

    Objective: To evaluate the results and complications of intercalary bone segment transport in the treatment of segmental tibial defects. Design: This is a retrospective analysis of patients with segmental tibial defects who were treated with intercalary bone segment transport method. Place and Duration of Study: The study was carried out at Combined Military Hospital, Rawalpindi from September 1997 to April 2001. Subjects and methods: Thirteen patients were included in the study who had developed tibial defects either due to open fractures with bone loss or subsequent to bone debridement of infected non unions. The mean bone defect was 6.4 cms and there were eight associated soft tissue defects. Locally made unilateral 'Naseer-Awais' (NA) fixator was used for bone segment transport. The distraction was done at the rate of 1mm/day after 7-10 days of osteotomy. The patients were followed-up fortnightly during distraction and monthly thereafter. The mean follow-up duration was 18 months. Results: The mean time in external fixation was 9.4 months. The m ean healing index' was 1.47 months/cm. Satisfactory union was achieved in all cases. Six cases (46.2%) required bone grafting at target site and in one of them grafting was required at the level of regeneration as well. All the wounds healed well with no residual infection. There was no residual leg length discrepancy of more than 20 mm nd one angular deformity of more than 5 degrees. The commonest complication encountered was pin track infection seen in 38% of Shanz Screws applied. Loosening occurred in 6.8% of Shanz screws, requiring re-adjustment. Ankle joint contracture with equinus deformity and peroneal nerve paresis occurred in one case each. The functional results were graded as 'good' in seven, 'fair' in four, and 'poor' in two patients. Overall, thirteen patients had 31 (minor/major) complications with a ratio of 2.38 complications per patient. To treat the bone defects and associated complications, a mean of

  11. Reusing Ceramic Tile Polishing Waste In Paving Block Manufacturing

    OpenAIRE

    Giordano Penteado; Carmenlucia Santos; de Carvalho; Eduardo Viviani; Cecche Lintz; Rosa Cristina

    2016-01-01

    Ceramic companies worldwide produce large amounts of polishing tile waste, which are piled up in the open air or disposed of in landfills. These wastes have such characteristics that make them potential substitutes for cement and sand in the manufacturing of concrete products. This paper investigates the use of ceramic tile polishing waste as a partial substitute for cement and sand in the manufacturer of concrete paving blocks. A concrete mix design was defined and then the sand was replaced...

  12. SPAM-assisted partial volume correction algorithm for PET

    International Nuclear Information System (INIS)

    Cho, Sung Il; Kang, Keon Wook; Lee, Jae Sung; Lee, Dong Soo; Chung, June Key; Soh, Kwang Sup; Lee, Myung Chul

    2000-01-01

    A probabilistic atlas of the human brain (Statistical Probability Anatomical Maps: SPAM) was developed by the International Consortium for Brain Mapping (ICBM). It will be a good frame for calculating volume of interest (VOI) according to statistical variability of human brain in many fields of brain images. We show that we can get more exact quantification of the counts in VOI by using SPAM in the correlation of partial volume effect for simulated PET image. The MRI of a patient with dementia was segmented into gray matter and white matter, and then they were smoothed to PET resolution. Simulated PET image was made by adding one third of the smoothed white matter to the smoothed gray matter. Spillover effect and partial volume effect were corrected for this simulated PET image with the aid of the segmented and smoothed MR images. The images were spatially normalized to the average brain MRI atlas of ICBM, and were multiplied by the probablities of 98 VOIs of SPAM images of Montreal Neurological Institute. After the correction of partial volume effect, the counts of frontal, partietal, temporal, and occipital lobes were increased by 38±6%, while those of hippocampus and amygdala by 4±3%. By calculating the counts in VOI using the product of probability of SPAM images and counts in the simulated PET image, the counts increase and become closer to the true values. SPAM-assisted partial volume correction is useful for quantification of VOIs in PET images

  13. SPAM-assisted partial volume correction algorithm for PET

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Sung Il; Kang, Keon Wook; Lee, Jae Sung; Lee, Dong Soo; Chung, June Key; Soh, Kwang Sup; Lee, Myung Chul [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2000-07-01

    A probabilistic atlas of the human brain (Statistical Probability Anatomical Maps: SPAM) was developed by the International Consortium for Brain Mapping (ICBM). It will be a good frame for calculating volume of interest (VOI) according to statistical variability of human brain in many fields of brain images. We show that we can get more exact quantification of the counts in VOI by using SPAM in the correlation of partial volume effect for simulated PET image. The MRI of a patient with dementia was segmented into gray matter and white matter, and then they were smoothed to PET resolution. Simulated PET image was made by adding one third of the smoothed white matter to the smoothed gray matter. Spillover effect and partial volume effect were corrected for this simulated PET image with the aid of the segmented and smoothed MR images. The images were spatially normalized to the average brain MRI atlas of ICBM, and were multiplied by the probablities of 98 VOIs of SPAM images of Montreal Neurological Institute. After the correction of partial volume effect, the counts of frontal, partietal, temporal, and occipital lobes were increased by 38{+-}6%, while those of hippocampus and amygdala by 4{+-}3%. By calculating the counts in VOI using the product of probability of SPAM images and counts in the simulated PET image, the counts increase and become closer to the true values. SPAM-assisted partial volume correction is useful for quantification of VOIs in PET images.

  14. Facile synthesis of main-chain degradable block copolymers for performance enhanced dismantlable adhesion.

    Science.gov (United States)

    Sato, Eriko; Hagihara, Takashi; Matsumoto, Akikazu

    2012-04-01

    Block copolymers consisting of readily degradable polyperoxides and non-degradable vinyl polymers as the block segments were successfully synthesized by reversible chain transfer catalyzed polymerization, which is one of living radical polymerization techniques. The block copolymers showed characteristic morphology and wettability being different from the polymer blends. When block copolymers containing polyperoxide and polymethacrylate blocks were heated below 150 °C, the polyperoxide blocks were completely degraded and the polymethacrylate blocks were recovered without degradation. Block copolymers containing a poly(2-ethylhexyl methacrylate) block were then investigated as a dismantlable adhesion material, which requires adequate bonding strength during use and easy debonding on demand. Among the several block copolymers, the one consisting of poly(2-ethylhexyl methacrylate) and polyperoxide from methyl sorbate (PPMS) (M(n) = 4900) exhibited good performance as a pressure-sensitive adhesive (PSA). After heating the test specimens in a temperature range from 60 to 100 °C, PSA performance, which was evaluated by 180° peel strength and shear holding power measurements, was significantly diminished. Especially, after heating at 100 °C for 1 h, spontaneous debonding of some test specimens was observed because of the evolution of volatile acetaldehyde from PPMS.

  15. Experts' understanding of partial derivatives using the Partial Derivative Machine

    OpenAIRE

    Roundy, David; Dorko, Allison; Dray, Tevian; Manogue, Corinne A.; Weber, Eric

    2014-01-01

    Partial derivatives are used in a variety of different ways within physics. Most notably, thermodynamics uses partial derivatives in ways that students often find confusing. As part of a collaboration with mathematics faculty, we are at the beginning of a study of the teaching of partial derivatives, a goal of better aligning the teaching of multivariable calculus with the needs of students in STEM disciplines. As a part of this project, we have performed a pilot study of expert understanding...

  16. Properties of Fly Ash Blocks Made from Adobe Mould

    Science.gov (United States)

    Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

    2018-06-01

    Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

  17. Properties of Fly Ash Blocks Made from Adobe Mould

    Science.gov (United States)

    Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

    2018-02-01

    Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

  18. Immunoglobulins of patients with idiopathic Addison's disease block the in vitro action of adrenocorticotropin

    NARCIS (Netherlands)

    Wulffraat, N. M.; Drexhage, H. A.; Bottazzo, G. F.; Wiersinga, W. M.; Jeucken, P.; van der Gaag, R.

    1989-01-01

    The presence of serum immunoglobulins (Ig) blocking ACTH-induced adrenal DNA synthesis and/or cortisol production was studied in 25 patients with idiopathic Addison's disease. For this purpose guinea pig adrenal segments kept in organ culture were exposed to ACTH and graded concentrations of patient

  19. Dictionary Based Segmentation in Volumes

    DEFF Research Database (Denmark)

    Emerson, Monica Jane; Jespersen, Kristine Munk; Jørgensen, Peter Stanley

    Method for supervised segmentation of volumetric data. The method is trained from manual annotations, and these annotations make the method very flexible, which we demonstrate in our experiments. Our method infers label information locally by matching the pattern in a neighborhood around a voxel ...... to a dictionary, and hereby accounts for the volume texture....

  20. Multiple Segmentation of Image Stacks

    DEFF Research Database (Denmark)

    Smets, Jonathan; Jaeger, Manfred

    2014-01-01

    We propose a method for the simultaneous construction of multiple image segmentations by combining a recently proposed “convolution of mixtures of Gaussians” model with a multi-layer hidden Markov random field structure. The resulting method constructs for a single image several, alternative...

  1. Segmenting Trajectories by Movement States

    NARCIS (Netherlands)

    Buchin, M.; Kruckenberg, H.; Kölzsch, A.; Timpf, S.; Laube, P.

    2013-01-01

    Dividing movement trajectories according to different movement states of animals has become a challenge in movement ecology, as well as in algorithm development. In this study, we revisit and extend a framework for trajectory segmentation based on spatio-temporal criteria for this purpose. We adapt

  2. Segmental Colitis Complicating Diverticular Disease

    Directory of Open Access Journals (Sweden)

    Guido Ma Van Rosendaal

    1996-01-01

    Full Text Available Two cases of idiopathic colitis affecting the sigmoid colon in elderly patients with underlying diverticulosis are presented. Segmental resection has permitted close review of the histopathology in this syndrome which demonstrates considerable similarity to changes seen in idiopathic ulcerative colitis. The reported experience with this syndrome and its clinical features are reviewed.

  3. Leaf segmentation in plant phenotyping

    NARCIS (Netherlands)

    Scharr, Hanno; Minervini, Massimo; French, Andrew P.; Klukas, Christian; Kramer, David M.; Liu, Xiaoming; Luengo, Imanol; Pape, Jean Michel; Polder, Gerrit; Vukadinovic, Danijela; Yin, Xi; Tsaftaris, Sotirios A.

    2016-01-01

    Image-based plant phenotyping is a growing application area of computer vision in agriculture. A key task is the segmentation of all individual leaves in images. Here we focus on the most common rosette model plants, Arabidopsis and young tobacco. Although leaves do share appearance and shape

  4. Conformal Nets II: Conformal Blocks

    Science.gov (United States)

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

    2017-08-01

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

  5. Harmony of spinning conformal blocks

    Energy Technology Data Exchange (ETDEWEB)

    Schomerus, Volker [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Sobko, Evgeny [Stockholm Univ. (Sweden); Nordita, Stockholm (Sweden); Isachenkov, Mikhail [Weizmann Institute of Science, Rehovoth (Israel). Dept. of Particle Physics and Astrophysics

    2016-12-07

    Conformal blocks for correlation functions of tensor operators play an increasingly important role for the conformal bootstrap programme. We develop a universal approach to such spinning blocks through the harmonic analysis of certain bundles over a coset of the conformal group. The resulting Casimir equations are given by a matrix version of the Calogero-Sutherland Hamiltonian that describes the scattering of interacting spinning particles in a 1-dimensional external potential. The approach is illustrated in several examples including fermionic seed blocks in 3D CFT where they take a very simple form.

  6. Harmony of spinning conformal blocks

    Energy Technology Data Exchange (ETDEWEB)

    Schomerus, Volker [DESY Hamburg, Theory Group,Notkestraße 85, 22607 Hamburg (Germany); Sobko, Evgeny [Nordita and Stockholm University,Roslagstullsbacken 23, SE-106 91 Stockholm (Sweden); Isachenkov, Mikhail [Department of Particle Physics and Astrophysics, Weizmann Institute of Science,Rehovot 7610001 (Israel)

    2017-03-15

    Conformal blocks for correlation functions of tensor operators play an increasingly important role for the conformal bootstrap programme. We develop a universal approach to such spinning blocks through the harmonic analysis of certain bundles over a coset of the conformal group. The resulting Casimir equations are given by a matrix version of the Calogero-Sutherland Hamiltonian that describes the scattering of interacting spinning particles in a 1-dimensional external potential. The approach is illustrated in several examples including fermionic seed blocks in 3D CFT where they take a very simple form.

  7. Comparison of extent of sensory block following posterior and subcostal approaches to ultrasound-guided transversus abdominis plane block.

    Science.gov (United States)

    Lee, T H W; Barrington, M J; Tran, T M N; Wong, D; Hebbard, P D

    2010-05-01

    Transversus abdominis plane block provides postoperative analgesia following abdominal surgery by targeting thoracolumbar nerves between the internal oblique and transversus abdominis muscles. Posterior and subcostal approaches using ultrasound guidance have been described. However there have been inconsistent results in relation to the extent of the sensory block. This observational study evaluated the distributions of sensory block following either a posterior or subcostal approach and the quality of analgesia achieved. Following ethics committee approval, 50 patients undergoing minimally invasive and major abdominal surgery were recruited. A total of 81 transversus abdominis plane blocks were performed preoperatively under real-time ultrasound guidance. Postoperatively, patients received multimodal analgesia including morphine via patient-controlled pumps. Ninety-eight percent of patients had some degree of demonstrable sensory block and the dermatomal spread differed between posterior and subcostal approaches (P interquartile range 2 to 4), the most cephalad being T10 (interquartile range T9 to T10), while the subcostal approach blocked a median of four segments (interquartile range 3 to 5), the most cephalad being T8 (interquartile range T7 to T9, P interquartile range 17 to 50 mg) at 24 hours. Median pain scores at rest and with coughing were 20 (interquartile range 10 to 35) and 50 (interquartile range 29 to 67) respectively at 24 hours. The posterior approach appears to be more appropriate for lower abdominal surgery and the subcostal approach better suited to upper abdominal surgery. Whichever approach is used, transversus abdominis plane block is only one component of a multimodal analgesic technique.

  8. [Partial replantation following proximal limb injury].

    Science.gov (United States)

    Dubert, T; Malikov, S A; Dinh, A; Kupatadze, D D; Oberlin, C; Alnot, J Y; Nabokov, B B

    2000-11-01

    Proximal replantation is a technically feasible but life-threatening procedure. Indications must be restricted to patients in good condition with a good functional prognosis. The goal of replantation must be focused not only on reimplanting the amputated limb but also on achieving a good functional outcome. For the lower limb, simple terminalization remains the best choice in many cases. When a proximal amputation is not suitable for replantation, the main aim of the surgical procedure must be to reconstruct a stump long enough to permit fitting a prosthesis preserving the function of the adjacent joint. If the proximal stump beyond the last joint is very short, it may be possible to restore some length by partial replantation of spared tissues from the amputated part. We present here the results we obtained following this policy. This series included 16 cases of partial replantations, 14 involving the lower limb and 2 the upper limb. All were osteocutaneous microsurgical transfers. For the lower limb, all transfers recovered protective sensitivity following tibial nerve repair. The functional calcaeoplantar unit was used in 13 cases. The transfer of this specialized weight bearing tissue provided a stable distal surface making higher support unnecessary. In one case, we raised a 13-cm vascularized tibial segment covered with foot skin for additional length. For the upper limb, the osteocutaneous transfer, based on the radial artery, was not reinnervated, but this lack of sensitivity did not impair prosthesis fitting. One vascular failure was finally amputated. This was the only unsuccessful result. For all other patients, the surgical procedure facilitated prosthesis fitting and preserved the proximal joint function despite an initially very proximal amputation. The advantages of partial replantation are obvious compared with simple terminalization or secondary reconstruction. There is no secondary donor site and, because there is no major muscle mass in the

  9. Joint Graph Layouts for Visualizing Collections of Segmented Meshes

    KAUST Repository

    Ren, Jing; Schneider, Jens; Ovsjanikov, Maks; Wonka, Peter

    2017-01-01

    We present a novel and efficient approach for computing joint graph layouts and then use it to visualize collections of segmented meshes. Our joint graph layout algorithm takes as input the adjacency matrices for a set of graphs along with partial, possibly soft, correspondences between nodes of different graphs. We then use a two stage procedure, where in the first step, we extend spectral graph drawing to include a consistency term so that a collection of graphs can be handled jointly. Our second step extends metric multi-dimensional scaling with stress majorization to the joint layout setting, while using the output of the spectral approach as initialization. Further, we discuss a user interface for exploring a collection of graphs. Finally, we show multiple example visualizations of graphs stemming from collections of segmented meshes and we present qualitative and quantitative comparisons with previous work.

  10. Joint Graph Layouts for Visualizing Collections of Segmented Meshes

    KAUST Repository

    Ren, Jing

    2017-09-12

    We present a novel and efficient approach for computing joint graph layouts and then use it to visualize collections of segmented meshes. Our joint graph layout algorithm takes as input the adjacency matrices for a set of graphs along with partial, possibly soft, correspondences between nodes of different graphs. We then use a two stage procedure, where in the first step, we extend spectral graph drawing to include a consistency term so that a collection of graphs can be handled jointly. Our second step extends metric multi-dimensional scaling with stress majorization to the joint layout setting, while using the output of the spectral approach as initialization. Further, we discuss a user interface for exploring a collection of graphs. Finally, we show multiple example visualizations of graphs stemming from collections of segmented meshes and we present qualitative and quantitative comparisons with previous work.

  11. Partial Actions and Power Sets

    Directory of Open Access Journals (Sweden)

    Jesús Ávila

    2013-01-01

    Full Text Available We consider a partial action (X,α with enveloping action (T,β. In this work we extend α to a partial action on the ring (P(X,Δ,∩ and find its enveloping action (E,β. Finally, we introduce the concept of partial action of finite type to investigate the relationship between (E,β and (P(T,β.

  12. Algorithms over partially ordered sets

    DEFF Research Database (Denmark)

    Baer, Robert M.; Østerby, Ole

    1969-01-01

    in partially ordered sets, answer the combinatorial question of how many maximal chains might exist in a partially ordered set withn elements, and we give an algorithm for enumerating all maximal chains. We give (in § 3) algorithms which decide whether a partially ordered set is a (lower or upper) semi......-lattice, and whether a lattice has distributive, modular, and Boolean properties. Finally (in § 4) we give Algol realizations of the various algorithms....

  13. Partial order infinitary term rewriting

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2014-01-01

    We study an alternative model of infinitary term rewriting. Instead of a metric on terms, a partial order on partial terms is employed to formalise convergence of reductions. We consider both a weak and a strong notion of convergence and show that the metric model of convergence coincides with th...... to the metric setting -- orthogonal systems are both infinitarily confluent and infinitarily normalising in the partial order setting. The unique infinitary normal forms that the partial order model admits are Böhm trees....

  14. Rolling block mazes are PSPACE-complete

    NARCIS (Netherlands)

    Buchin, K.; Buchin, M.

    2012-01-01

    In a rolling block maze, one or more blocks lie on a rectangular board with square cells. In most mazes, the blocks have size k × m × n where k, m, n are integers that determine the size of the block in terms of units of the size of the board cells. The task of a rolling block maze is to roll a

  15. Left bundle-branch block

    DEFF Research Database (Denmark)

    Risum, Niels; Strauss, David; Sogaard, Peter

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  16. Recursion Relations for Conformal Blocks

    CERN Document Server

    Penedones, João; Yamazaki, Masahito

    2016-09-12

    In the context of conformal field theories in general space-time dimension, we find all the possible singularities of the conformal blocks as functions of the scaling dimension $\\Delta$ of the exchanged operator. In particular, we argue, using representation theory of parabolic Verma modules, that in odd spacetime dimension the singularities are only simple poles. We discuss how to use this information to write recursion relations that determine the conformal blocks. We first recover the recursion relation introduced in 1307.6856 for conformal blocks of external scalar operators. We then generalize this recursion relation for the conformal blocks associated to the four point function of three scalar and one vector operator. Finally we specialize to the case in which the vector operator is a conserved current.

  17. Defying gravity using Jenga™ blocks

    Science.gov (United States)

    Tan, Yin-Soo; Yap, Kueh-Chin

    2007-11-01

    This paper describes how Jenga™ blocks can be used to demonstrate the physics of an overhanging tower that appears to defy gravity. We also propose ideas for how this demonstration can be adapted for the A-level physics curriculum.

  18. Risking Aggression: Reply to Block

    Directory of Open Access Journals (Sweden)

    Kris Borer

    2010-05-01

    Full Text Available In his paper, “Is There an ‘Anomalous’ Section of the Laffer Curve?”, Walter Block describes some situations in which it appears that a libertarian should violate the non-aggression principle. To rectify this, Block proposes a different perspective on libertarianism which he calls punishment theory. This paper argues that no new theory is needed, as the non-aggression principle can be used to resolve theapparent conundrums.

  19. Risking Aggression: Reply to Block

    OpenAIRE

    Kris Borer

    2010-01-01

    In his paper, “Is There an ‘Anomalous’ Section of the Laffer Curve?”, Walter Block describes some situations in which it appears that a libertarian should violate the non-aggression principle. To rectify this, Block proposes a different perspective on libertarianism which he calls punishment theory. This paper argues that no new theory is needed, as the non-aggression principle can be used to resolve theapparent conundrums.

  20. A Novel Tetrathiafulvalene Building Block

    DEFF Research Database (Denmark)

    Jeppesen, Jan Oskar; Takimiya, Kazuo; Thorup, Niels

    1999-01-01

    Efficient synthesis of a novel tetrathiafulvalene building block. 2,3-bis(2-cyanoethylthio)-6,7-bis(thiocyanato-methyl)tetrathiafulv alene (7) useful for stepwise and asymmetrical bis-function-alization is reported.......Efficient synthesis of a novel tetrathiafulvalene building block. 2,3-bis(2-cyanoethylthio)-6,7-bis(thiocyanato-methyl)tetrathiafulv alene (7) useful for stepwise and asymmetrical bis-function-alization is reported....

  1. Traces of warping subsided tectonic blocks on Miranda, Enceladus, Titan

    Science.gov (United States)

    Kochemasov, G.

    2007-08-01

    Icy satellites of the outer Solar system have very large range of sizes - from kilometers to thousands of kilometers. Bodies less than 400-500 km across have normally irregular shapes , often presenting simple Plato's polyhedrons woven by standing inertiagravity waves (see an accompanying abstract of Kochemasov). Larger bodies with enhanced gravity normally are rounded off and have globular shapes but far from ideal spheres. This is due to warping action of inertia-gravity waves of various wavelengths origin of which is related to body movements in elliptical keplerian orbits with periodically changing accelerations (alternating accelerations cause periodically changing forces acting upon a body what means oscillations of its spheres in form of standing warping waves). The fundamental wave 1 and its first overtone wave 2 produce ubiquitous tectonic dichotomy - two segmental structure and tectonic sectoring superimposed on this dichotomy. Two kinds of tectonic blocks (segments and sectors) are formed: uplifted (+) and subsided (-). Uplifting means increasing planetary radius of blocks, subsiding - decreasing radius (as a sequence subsiding blocks diminishing their surfaces must be warped, folded, wrinkled; uplifting blocks increasing their surfaces tend to be deeply cracked, fallen apart). To level changing angular momenta of blocks subsided areas are filled with denser material than uplifted ones (one of the best examples is Earth with its oceanic basins filled with dense basalts and uplifted continents built of less dense on average andesitic material). Icy satellites follow the same rule. Their warped surfaces show differing chemistries or structures of constructive materials. Uplifted blocks are normally built with light (by color and density) water ice. Subsided blocks - depressions, "seas', "lakes", coronas - by somewhat denser material differing in color from water ice (very sharply - Iapetus, moderately - Europa, slightly - many saturnian satellites). A very

  2. Image segmentation-based robust feature extraction for color image watermarking

    Science.gov (United States)

    Li, Mianjie; Deng, Zeyu; Yuan, Xiaochen

    2018-04-01

    This paper proposes a local digital image watermarking method based on Robust Feature Extraction. The segmentation is achieved by Simple Linear Iterative Clustering (SLIC) based on which an Image Segmentation-based Robust Feature Extraction (ISRFE) method is proposed for feature extraction. Our method can adaptively extract feature regions from the blocks segmented by SLIC. This novel method can extract the most robust feature region in every segmented image. Each feature region is decomposed into low-frequency domain and high-frequency domain by Discrete Cosine Transform (DCT). Watermark images are then embedded into the coefficients in the low-frequency domain. The Distortion-Compensated Dither Modulation (DC-DM) algorithm is chosen as the quantization method for embedding. The experimental results indicate that the method has good performance under various attacks. Furthermore, the proposed method can obtain a trade-off between high robustness and good image quality.

  3. Dynamic segment shared protection for multicast traffic in meshed wavelength-division-multiplexing optical networks

    Science.gov (United States)

    Liao, Luhua; Li, Lemin; Wang, Sheng

    2006-12-01

    We investigate the protection approach for dynamic multicast traffic under shared risk link group (SRLG) constraints in meshed wavelength-division-multiplexing optical networks. We present a shared protection algorithm called dynamic segment shared protection for multicast traffic (DSSPM), which can dynamically adjust the link cost according to the current network state and can establish a primary light-tree as well as corresponding SRLG-disjoint backup segments for a dependable multicast connection. A backup segment can efficiently share the wavelength capacity of its working tree and the common resources of other backup segments based on SRLG-disjoint constraints. The simulation results show that DSSPM not only can protect the multicast sessions against a single-SRLG breakdown, but can make better use of the wavelength resources and also lower the network blocking probability.

  4. Fault segmentation: New concepts from the Wasatch Fault Zone, Utah, USA

    Science.gov (United States)

    Duross, Christopher; Personius, Stephen F.; Crone, Anthony J.; Olig, Susan S.; Hylland, Michael D.; Lund, William R.; Schwartz, David P.

    2016-01-01

    The question of whether structural segment boundaries along multisegment normal faults such as the Wasatch fault zone (WFZ) act as persistent barriers to rupture is critical to seismic hazard analyses. We synthesized late Holocene paleoseismic data from 20 trench sites along the central WFZ to evaluate earthquake rupture length and fault segmentation. For the youngest (segment boundaries, especially for the most recent earthquakes on the north-central WFZ, are consistent with segment-controlled ruptures. However, broadly constrained earthquake times, dissimilar event times along the segments, the presence of smaller-scale (subsegment) boundaries, and areas of complex faulting permit partial-segment and multisegment (e.g., spillover) ruptures that are shorter (~20–40 km) or longer (~60–100 km) than the primary segment lengths (35–59 km). We report a segmented WFZ model that includes 24 earthquakes since ~7 ka and yields mean estimates of recurrence (1.1–1.3 kyr) and vertical slip rate (1.3–2.0 mm/yr) for the segments. However, additional rupture scenarios that include segment boundary spatial uncertainties, floating earthquakes, and multisegment ruptures are necessary to fully address epistemic uncertainties in rupture length. We compare the central WFZ to paleoseismic and historical surface ruptures in the Basin and Range Province and central Italian Apennines and conclude that displacement profiles have limited value for assessing the persistence of segment boundaries but can aid in interpreting prehistoric spillover ruptures. Our comparison also suggests that the probabilities of shorter and longer ruptures on the WFZ need to be investigated.

  5. An explicit statistical model of learning lexical segmentation using multiple cues

    NARCIS (Netherlands)

    Çöltekin, Ça ̆grı; Nerbonne, John; Lenci, Alessandro; Padró, Muntsa; Poibeau, Thierry; Villavicencio, Aline

    2014-01-01

    This paper presents an unsupervised and incremental model of learning segmentation that combines multiple cues whose use by children and adults were attested by experimental studies. The cues we exploit in this study are predictability statistics, phonotactics, lexical stress and partial lexical

  6. Oral rehabilitation of segmental mandibulectomy patient with osseointegrated dental implant

    Directory of Open Access Journals (Sweden)

    Archana Singh

    2014-01-01

    Full Text Available Surgical management of oral cancer lesions results in explicit aesthetic and functional disfigurement, including facial deformity, loss of hard and soft tissue, impaired speech, swallowing and mastication, which modify the patient′s self-image and quality-of-life. Recent advances in head and neck reconstruction techniques and dental implant based prosthetic rehabilitation may significantly improve the quality-of-life and self-esteem for such post-surgery patients. This clinical report describes rehabilitation of oral cancer patient having segmental mandibulectomy with implant-supported fixed partial denture.

  7. Sparse multi-block PLSR for biomarker discovery when integrating data from LC-MS and NMR metabolomics

    DEFF Research Database (Denmark)

    Karaman, Ibrahim; Nørskov, Natalja; Yde, Christian Clement

    2015-01-01

    The objective of this study was to implement a multivariate method which analyzes multi-block metabolomics data and performs variable selection in order to discover potential biomarkers, simultaneously. We call this method sparse multi-block partial least squares regression (Sparse MBPLSR). To ac...

  8. Comparative study between ultrasound guided TAP block and paravertebral block in upper abdominal surgeries

    Directory of Open Access Journals (Sweden)

    Ruqaya M Elsayed Goda

    2017-01-01

    Conclusion: We concluded that ultrasound guided transverses abdominis plane block and thoracic paravertebral block were safe and effective anesthetic technique for upper abdominal surgery with longer and potent postoperative analgesia in thoracic paravertebral block than transverses abdominis block.

  9. On Degenerate Partial Differential Equations

    OpenAIRE

    Chen, Gui-Qiang G.

    2010-01-01

    Some of recent developments, including recent results, ideas, techniques, and approaches, in the study of degenerate partial differential equations are surveyed and analyzed. Several examples of nonlinear degenerate, even mixed, partial differential equations, are presented, which arise naturally in some longstanding, fundamental problems in fluid mechanics and differential geometry. The solution to these fundamental problems greatly requires a deep understanding of nonlinear degenerate parti...

  10. [Acrylic resin removable partial dentures

    NARCIS (Netherlands)

    Baat, C. de; Witter, D.J.; Creugers, N.H.J.

    2011-01-01

    An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of

  11. Partial Epilepsy with Auditory Features

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-07-01

    Full Text Available The clinical characteristics of 53 sporadic (S cases of idiopathic partial epilepsy with auditory features (IPEAF were analyzed and compared to previously reported familial (F cases of autosomal dominant partial epilepsy with auditory features (ADPEAF in a study at the University of Bologna, Italy.

  12. Dictionary Based Segmentation in Volumes

    DEFF Research Database (Denmark)

    Emerson, Monica Jane; Jespersen, Kristine Munk; Jørgensen, Peter Stanley

    2015-01-01

    We present a method for supervised volumetric segmentation based on a dictionary of small cubes composed of pairs of intensity and label cubes. Intensity cubes are small image volumes where each voxel contains an image intensity. Label cubes are volumes with voxelwise probabilities for a given...... label. The segmentation process is done by matching a cube from the volume, of the same size as the dictionary intensity cubes, to the most similar intensity dictionary cube, and from the associated label cube we get voxel-wise label probabilities. Probabilities from overlapping cubes are averaged...... and hereby we obtain a robust label probability encoding. The dictionary is computed from labeled volumetric image data based on weighted clustering. We experimentally demonstrate our method using two data sets from material science – a phantom data set of a solid oxide fuel cell simulation for detecting...

  13. Compliance with Segment Disclosure Initiatives

    DEFF Research Database (Denmark)

    Arya, Anil; Frimor, Hans; Mittendorf, Brian

    2013-01-01

    Regulatory oversight of capital markets has intensified in recent years, with a particular emphasis on expanding financial transparency. A notable instance is efforts by the Financial Accounting Standards Board that push firms to identify and report performance of individual business units...... (segments). This paper seeks to address short-run and long-run consequences of stringent enforcement of and uniform compliance with these segment disclosure standards. To do so, we develop a parsimonious model wherein a regulatory agency promulgates disclosure standards and either permits voluntary...... by increasing transparency and leveling the playing field. However, our analysis also demonstrates that in the long run, if firms are unable to use discretion in reporting to maintain their competitive edge, they may seek more destructive alternatives. Accounting for such concerns, in the long run, voluntary...

  14. Segmental osteotomies of the maxilla.

    Science.gov (United States)

    Rosen, H M

    1989-10-01

    Multiple segment Le Fort I osteotomies provide the maxillofacial surgeon with the capabilities to treat complex dentofacial deformities existing in all three planes of space. Sagittal, vertical, and transverse maxillomandibular discrepancies as well as three-dimensional abnormalities within the maxillary arch can be corrected simultaneously. Accordingly, optimal aesthetic enhancement of the facial skeleton and a functional, healthy occlusion can be realized. What may be perceived as elaborate treatment plans are in reality conservative in terms of osseous stability and treatment time required. The close cooperation of an orthodontist well-versed in segmental orthodontics and orthognathic surgery is critical to the success of such surgery. With close attention to surgical detail, the complication rate inherent in such surgery can be minimized and the treatment goals achieved in a timely and predictable fashion.

  15. Partial twisting for scalar mesons

    International Nuclear Information System (INIS)

    Agadjanov, Dimitri; Meißner, Ulf-G.; Rusetsky, Akaki

    2014-01-01

    The possibility of imposing partially twisted boundary conditions is investigated for the scalar sector of lattice QCD. According to the commonly shared belief, the presence of quark-antiquark annihilation diagrams in the intermediate state generally hinders the use of the partial twisting. Using effective field theory techniques in a finite volume, and studying the scalar sector of QCD with total isospin I=1, we however demonstrate that partial twisting can still be performed, despite the fact that annihilation diagrams are present. The reason for this are delicate cancellations, which emerge due to the graded symmetry in partially quenched QCD with valence, sea and ghost quarks. The modified Lüscher equation in case of partial twisting is given

  16. Segmented fuel and moderator rod

    International Nuclear Information System (INIS)

    Doshi, P.K.

    1987-01-01

    This patent describes a continuous segmented fuel and moderator rod for use with a water cooled and moderated nuclear fuel assembly. The rod comprises: a lower fuel region containing a column of nuclear fuel; a moderator region, disposed axially above the fuel region. The moderator region has means for admitting and passing the water moderator therethrough for moderating an upper portion of the nuclear fuel assembly. The moderator region is separated from the fuel region by a water tight separator

  17. Segmentation of sows in farrowing pens

    DEFF Research Database (Denmark)

    Tu, Gang Jun; Karstoft, Henrik; Pedersen, Lene Juul

    2014-01-01

    The correct segmentation of a foreground object in video recordings is an important task for many surveillance systems. The development of an effective and practical algorithm to segment sows in grayscale video recordings captured under commercial production conditions is described...

  18. Segmentation in local hospital markets.

    Science.gov (United States)

    Dranove, D; White, W D; Wu, L

    1993-01-01

    This study examines evidence of market segmentation on the basis of patients' insurance status, demographic characteristics, and medical condition in selected local markets in California in the years 1983 and 1989. Substantial differences exist in the probability patients may be admitted to particular hospitals based on insurance coverage, particularly Medicaid, and race. Segmentation based on insurance and race is related to hospital characteristics, but not the characteristics of the hospital's community. Medicaid patients are more likely to go to hospitals with lower costs and fewer service offerings. Privately insured patients go to hospitals offering more services, although cost concerns are increasing. Hispanic patients also go to low-cost hospitals, ceteris paribus. Results indicate little evidence of segmentation based on medical condition in either 1983 or 1989, suggesting that "centers of excellence" have yet to play an important role in patient choice of hospital. The authors found that distance matters, and that patients prefer nearby hospitals, moreso for some medical conditions than others, in ways consistent with economic theories of consumer choice.

  19. Various semiclassical limits of torus conformal blocks

    Energy Technology Data Exchange (ETDEWEB)

    Alkalaev, Konstantin [I.E. Tamm Department of Theoretical Physics, P.N. Lebedev Physical Institute,Leninsky ave. 53, Moscow, 119991 (Russian Federation); Department of General and Applied Physics, Moscow Institute of Physics and Technology,Institutskiy per. 7, Dolgoprudnyi, Moscow region, 141700 (Russian Federation); Geiko, Roman [Mathematics Department, National Research University Higher School of Economics,Usacheva str. 6, Moscow, 119048 (Russian Federation); Rappoport, Vladimir [I.E. Tamm Department of Theoretical Physics, P.N. Lebedev Physical Institute,Leninsky ave. 53, Moscow, 119991 (Russian Federation); Department of Quantum Physics, Institute for Information Transmission Problems,Bolshoy Karetny per. 19, Moscow, 127994 (Russian Federation)

    2017-04-12

    We study four types of one-point torus blocks arising in the large central charge regime. There are the global block, the light block, the heavy-light block, and the linearized classical block, according to different regimes of conformal dimensions. It is shown that the blocks are not independent being connected to each other by various links. We find that the global, light, and heavy-light blocks correspond to three different contractions of the Virasoro algebra. Also, we formulate the c-recursive representation of the one-point torus blocks which is relevant in the semiclassical approximation.

  20. Roentgenological diagnoss of central segmental lung cancer

    International Nuclear Information System (INIS)

    Gurevich, L.A.; Fedchenko, G.G.

    1984-01-01

    Basing on an analysis of the results of clinicoroentgenological examination of 268 patments roentgenological semiotics of segmental lung cancer is presented. Some peculiarities of the X-ray picture of cancer of different segments of the lungs were revealed depending on tumor site and growth type. For the syndrome of segmental darkening the comprehensive X-ray methods where the chief method is tomography of the segmental bronchi are proposed

  1. Review of segmentation process in consumer markets

    OpenAIRE

    Veronika Jadczaková

    2013-01-01

    Although there has been a considerable debate on market segmentation over five decades, attention was merely devoted to single stages of the segmentation process. In doing so, stages as segmentation base selection or segments profiling have been heavily covered in the extant literature, whereas stages as implementation of the marketing strategy or market definition were of a comparably lower interest. Capitalizing on this shortcoming, this paper strives to close the gap and provide each step...

  2. Image segmentation with a novel regularized composite shape prior based on surrogate study

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Tingting, E-mail: tingtingzhao@mednet.ucla.edu; Ruan, Dan, E-mail: druan@mednet.ucla.edu [The Department of Radiation Oncology, University of California, Los Angeles, California 90095 (United States)

    2016-05-15

    Purpose: Incorporating training into image segmentation is a good approach to achieve additional robustness. This work aims to develop an effective strategy to utilize shape prior knowledge, so that the segmentation label evolution can be driven toward the desired global optimum. Methods: In the variational image segmentation framework, a regularization for the composite shape prior is designed to incorporate the geometric relevance of individual training data to the target, which is inferred by an image-based surrogate relevance metric. Specifically, this regularization is imposed on the linear weights of composite shapes and serves as a hyperprior. The overall problem is formulated in a unified optimization setting and a variational block-descent algorithm is derived. Results: The performance of the proposed scheme is assessed in both corpus callosum segmentation from an MR image set and clavicle segmentation based on CT images. The resulted shape composition provides a proper preference for the geometrically relevant training data. A paired Wilcoxon signed rank test demonstrates statistically significant improvement of image segmentation accuracy, when compared to multiatlas label fusion method and three other benchmark active contour schemes. Conclusions: This work has developed a novel composite shape prior regularization, which achieves superior segmentation performance than typical benchmark schemes.

  3. Image segmentation with a novel regularized composite shape prior based on surrogate study

    International Nuclear Information System (INIS)

    Zhao, Tingting; Ruan, Dan

    2016-01-01

    Purpose: Incorporating training into image segmentation is a good approach to achieve additional robustness. This work aims to develop an effective strategy to utilize shape prior knowledge, so that the segmentation label evolution can be driven toward the desired global optimum. Methods: In the variational image segmentation framework, a regularization for the composite shape prior is designed to incorporate the geometric relevance of individual training data to the target, which is inferred by an image-based surrogate relevance metric. Specifically, this regularization is imposed on the linear weights of composite shapes and serves as a hyperprior. The overall problem is formulated in a unified optimization setting and a variational block-descent algorithm is derived. Results: The performance of the proposed scheme is assessed in both corpus callosum segmentation from an MR image set and clavicle segmentation based on CT images. The resulted shape composition provides a proper preference for the geometrically relevant training data. A paired Wilcoxon signed rank test demonstrates statistically significant improvement of image segmentation accuracy, when compared to multiatlas label fusion method and three other benchmark active contour schemes. Conclusions: This work has developed a novel composite shape prior regularization, which achieves superior segmentation performance than typical benchmark schemes.

  4. Market Segmentation from a Behavioral Perspective

    Science.gov (United States)

    Wells, Victoria K.; Chang, Shing Wan; Oliveira-Castro, Jorge; Pallister, John

    2010-01-01

    A segmentation approach is presented using both traditional demographic segmentation bases (age, social class/occupation, and working status) and a segmentation by benefits sought. The benefits sought in this case are utilitarian and informational reinforcement, variables developed from the Behavioral Perspective Model (BPM). Using data from 1,847…

  5. Parallel fuzzy connected image segmentation on GPU

    OpenAIRE

    Zhuge, Ying; Cao, Yong; Udupa, Jayaram K.; Miller, Robert W.

    2011-01-01

    Purpose: Image segmentation techniques using fuzzy connectedness (FC) principles have shown their effectiveness in segmenting a variety of objects in several large applications. However, one challenge in these algorithms has been their excessive computational requirements when processing large image datasets. Nowadays, commodity graphics hardware provides a highly parallel computing environment. In this paper, the authors present a parallel fuzzy connected image segmentation algorithm impleme...

  6. LIFE-STYLE SEGMENTATION WITH TAILORED INTERVIEWING

    NARCIS (Netherlands)

    KAMAKURA, WA; WEDEL, M

    The authors present a tailored interviewing procedure for life-style segmentation. The procedure assumes that a life-style measurement instrument has been designed. A classification of a sample of consumers into life-style segments is obtained using a latent-class model. With these segments, the

  7. The Process of Marketing Segmentation Strategy Selection

    OpenAIRE

    Ionel Dumitru

    2007-01-01

    The process of marketing segmentation strategy selection represents the essence of strategical marketing. We present hereinafter the main forms of the marketing statategy segmentation: undifferentiated marketing, differentiated marketing, concentrated marketing and personalized marketing. In practice, the companies use a mix of these marketing segmentation methods in order to maximize the proffit and to satisfy the consumers’ needs.

  8. Cast Partial Denture versus Acrylic Partial Denture for Replacement of Missing Teeth in Partially Edentulous Patients

    Directory of Open Access Journals (Sweden)

    Pramita Suwal

    2017-03-01

    Full Text Available Aim: To compare the effects of cast partial denture with conventional all acrylic denture in respect to retention, stability, masticatory efficiency, comfort and periodontal health of abutments. Methods: 50 adult partially edentulous patient seeking for replacement of missing teeth having Kennedy class I and II arches with or without modification areas were selected for the study. Group-A was treated with cast partial denture and Group-B with acrylic partial denture. Data collected during follow-up visit of 3 months, 6 months, and 1 year by evaluating retention, stability, masticatory efficiency, comfort, periodontal health of abutment. Results: Chi-square test was applied to find out differences between the groups at 95% confidence interval where p = 0.05. One year comparison shows that cast partial denture maintained retention and stability better than acrylic partial denture (p< 0.05. The masticatory efficiency was significantly compromising from 3rd month to 1 year in all acrylic partial denture groups (p< 0.05. The comfort of patient with cast partial denture was maintained better during the observation period (p< 0.05. Periodontal health of abutment was gradually deteriorated in all acrylic denture group (p

  9. High-speed MRF-based segmentation algorithm using pixonal images

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Hassanpour, H.; Naimi, H. M.

    2013-01-01

    Segmentation is one of the most complicated procedures in the image processing that has important role in the image analysis. In this paper, an improved pixon-based method for image segmentation is proposed. In proposed algorithm, complex partial differential equations (PDEs) is used as a kernel...... function to make pixonal image. Using this kernel function causes noise on images to reduce and an image not to be over-segment when the pixon-based method is used. Utilising the PDE-based method leads to elimination of some unnecessary details and results in a fewer pixon number, faster performance...... and more robustness against unwanted environmental noises. As the next step, the appropriate pixons are extracted and eventually, we segment the image with the use of a Markov random field. The experimental results indicate that the proposed pixon-based approach has a reduced computational load...

  10. Climatological features of blocking anticyclones

    International Nuclear Information System (INIS)

    Lupo, A.R.; Smith, P.J.; Oglesby, R.J.

    1994-01-01

    Several climatological studies have been previously performed using large observational data sets (i.e., 10 years or longer) in order to determine the predominant characteristics of blocking anticyclones, including favored development regions, duration, preferred seasonal occurrence, and frequency of occurrence. These studies have shown that blocking anticyclones occur most frequently from October to April over the eastern Atlantic and Pacific oceans downstream from both the North American and Asian continental regions and the storm track regions to the east of these continents. Some studies have also revealed the presence of a third region block formation in western Russia near 40 degrees E which is associated with another storm track region over the Mediterranean and western Asia

  11. Block ground interaction of rockfalls

    Science.gov (United States)

    Volkwein, Axel; Gerber, Werner; Kummer, Peter

    2016-04-01

    During a rockfall the interaction of the falling block with the ground is one of the most important factors that define the evolution of a rockfall trajectory. It steers the rebound, the rotational movement, possibly brake effects, friction losses and damping effects. Therefore, if most reliable rockfall /trajectory simulation software is sought a good understanding of the block ground interaction is necessary. Today's rockfall codes enable the simulation of a fully 3D modelled block within a full 3D surface . However, the details during the contact, i.e. the contact duration, the penetration depth or the dimension of the marks in the ground are usually not part of the simulation. Recent field tests with rocks between 20 and 80 kg have been conducted on a grassy slope in 2014 [1]. A special rockfall sensor [2] within the blocks measured the rotational velocity and the acting accelerations during the tests. External video records and a so-called LocalPositioningSystem deliver information on the travel velocity. With these data not only the flight phases of the trajectories but also the contacts with the ground can be analysed. During the single jumps of a block the flight time, jump length, the velocity, and the rotation are known. During the single impacts their duration and the acting accelerations are visible. Further, the changes of rotational and translational velocity influence the next jump of the block. The change of the rotational velocity over the whole trajectory nicely visualizes the different phases of a rockfall regarding general acceleration and deceleration in respect to the inclination and the topography of the field. References: [1] Volkwein A, Krummenacher B, Gerber W, Lardon J, Gees F, Brügger L, Ott T (2015) Repeated controlled rockfall trajectory testing. [Abstract] Geophys. Res. Abstr. 17: EGU2015-9779. [2] Volkwein A, Klette J (2014) Semi-Automatic Determination of Rockfall Trajectories. Sensors 14: 18187-18210.

  12. Cryptanalysis of Selected Block Ciphers

    DEFF Research Database (Denmark)

    Alkhzaimi, Hoda A.

    , pseudorandom number generators, and authenticated encryption designs. For this reason a multitude of initiatives over the years has been established to provide a secure and sound designs for block ciphers as in the calls for Data Encryption Standard (DES) and Advanced Encryption Standard (AES), lightweight...... ciphers initiatives, and the Competition for Authenticated Encryption: Security, Applicability, and Robustness (CAESAR). In this thesis, we first present cryptanalytic results on different ciphers. We propose attack named the Invariant Subspace Attack. It is utilized to break the full block cipher...

  13. Automatic segmentation of vertebrae from radiographs

    DEFF Research Database (Denmark)

    Mysling, Peter; Petersen, Peter Kersten; Nielsen, Mads

    2011-01-01

    Segmentation of vertebral contours is an essential task in the design of automatic tools for vertebral fracture assessment. In this paper, we propose a novel segmentation technique which does not require operator interaction. The proposed technique solves the segmentation problem in a hierarchical...... is constrained by a conditional shape model, based on the variability of the coarse spine location estimates. The technique is evaluated on a data set of manually annotated lumbar radiographs. The results compare favorably to the previous work in automatic vertebra segmentation, in terms of both segmentation...

  14. Color image Segmentation using automatic thresholding techniques

    International Nuclear Information System (INIS)

    Harrabi, R.; Ben Braiek, E.

    2011-01-01

    In this paper, entropy and between-class variance based thresholding methods for color images segmentation are studied. The maximization of the between-class variance (MVI) and the entropy (ME) have been used as a criterion functions to determine an optimal threshold to segment images into nearly homogenous regions. Segmentation results from the two methods are validated and the segmentation sensitivity for the test data available is evaluated, and a comparative study between these methods in different color spaces is presented. The experimental results demonstrate the superiority of the MVI method for color image segmentation.

  15. MOVING WINDOW SEGMENTATION FRAMEWORK FOR POINT CLOUDS

    Directory of Open Access Journals (Sweden)

    G. Sithole

    2012-07-01

    Full Text Available As lidar point clouds become larger streamed processing becomes more attractive. This paper presents a framework for the streamed segmentation of point clouds with the intention of segmenting unstructured point clouds in real-time. The framework is composed of two main components. The first component segments points within a window shifting over the point cloud. The second component stitches the segments within the windows together. In this fashion a point cloud can be streamed through these two components in sequence, thus producing a segmentation. The algorithm has been tested on airborne lidar point cloud and some results of the performance of the framework are presented.

  16. Segmentation of hepatic artery in multi-phase liver CT using directional dilation and connectivity analysis

    Science.gov (United States)

    Wang, Lei; Schnurr, Alena-Kathrin; Zidowitz, Stephan; Georgii, Joachim; Zhao, Yue; Razavi, Mohammad; Schwier, Michael; Hahn, Horst K.; Hansen, Christian

    2016-03-01

    Segmentation of hepatic arteries in multi-phase computed tomography (CT) images is indispensable in liver surgery planning. During image acquisition, the hepatic artery is enhanced by the injection of contrast agent. The enhanced signals are often not stably acquired due to non-optimal contrast timing. Other vascular structure, such as hepatic vein or portal vein, can be enhanced as well in the arterial phase, which can adversely affect the segmentation results. Furthermore, the arteries might suffer from partial volume effects due to their small diameter. To overcome these difficulties, we propose a framework for robust hepatic artery segmentation requiring a minimal amount of user interaction. First, an efficient multi-scale Hessian-based vesselness filter is applied on the artery phase CT image, aiming to enhance vessel structures with specified diameter range. Second, the vesselness response is processed using a Bayesian classifier to identify the most probable vessel structures. Considering the vesselness filter normally performs not ideally on the vessel bifurcations or the segments corrupted by noise, two vessel-reconnection techniques are proposed. The first technique uses a directional morphological operator to dilate vessel segments along their centerline directions, attempting to fill the gap between broken vascular segments. The second technique analyzes the connectivity of vessel segments and reconnects disconnected segments and branches. Finally, a 3D vessel tree is reconstructed. The algorithm has been evaluated using 18 CT images of the liver. To quantitatively measure the similarities between segmented and reference vessel trees, the skeleton coverage and mean symmetric distance are calculated to quantify the agreement between reference and segmented vessel skeletons, resulting in an average of 0:55+/-0:27 and 12:7+/-7:9 mm (mean standard deviation), respectively.

  17. Segmentation of urinary bladder in CT urography (CTU) using CLASS with enhanced contour conjoint procedure

    Science.gov (United States)

    Cha, Kenny; Hadjiiski, Lubomir; Chan, Heang-Ping; Cohan, Richard H.; Caoili, Elaine M.; Zhou, Chuan

    2014-03-01

    We are developing a computerized method for bladder segmentation in CT urography (CTU) for computeraided diagnosis of bladder cancer. A challenge for computerized bladder segmentation in CTU is that the bladder often contains regions filled with intravenous (IV) contrast and without contrast. Previously, we proposed a Conjoint Level set Analysis and Segmentation System (CLASS) consisting of four stages: preprocessing and initial segmentation, 3D and 2D level set segmentation, and post-processing. In case the bladder is partially filled with contrast, CLASS segments the non-contrast (NC) region and the contrast (C) filled region separately and conjoins the contours with a Contour Conjoint Procedure (CCP). The CCP is not trivial. Inaccuracies in the NC and C contours may cause CCP to exclude portions of the bladder. To alleviate this problem, we implemented model-guided refinement to propagate the C contour if the level set propagation in the region stops prematurely due to substantial non-uniformity of the contrast. An enhanced CCP with regularized energies further propagates the conjoint contours to the correct bladder boundary. Segmentation performance was evaluated using 70 cases. For all cases, 3D hand segmented contours were obtained as reference standard, and computerized segmentation accuracy was evaluated in terms of average volume intersection %, average % volume error, and average minimum distance. With enhanced CCP, those values were 84.4±10.6%, 8.3±16.1%, 3.4±1.8 mm, respectively. With CLASS, those values were 74.6±13.1%, 19.6±18.6%, 4.4±2.2 mm, respectively. The enhanced CCP improved bladder segmentation significantly (p<0.001) for all three performance measures.

  18. Fully-automated approach to hippocampus segmentation using a graph-cuts algorithm combined with atlas-based segmentation and morphological opening.

    Science.gov (United States)

    Kwak, Kichang; Yoon, Uicheul; Lee, Dong-Kyun; Kim, Geon Ha; Seo, Sang Won; Na, Duk L; Shim, Hack-Joon; Lee, Jong-Min

    2013-09-01

    The hippocampus has been known to be an important structure as a biomarker for Alzheimer's disease (AD) and other neurological and psychiatric diseases. However, it requires accurate, robust and reproducible delineation of hippocampal structures. In this study, an automated hippocampal segmentation method based on a graph-cuts algorithm combined with atlas-based segmentation and morphological opening was proposed. First of all, the atlas-based segmentation was applied to define initial hippocampal region for a priori information on graph-cuts. The definition of initial seeds was further elaborated by incorporating estimation of partial volume probabilities at each voxel. Finally, morphological opening was applied to reduce false positive of the result processed by graph-cuts. In the experiments with twenty-seven healthy normal subjects, the proposed method showed more reliable results (similarity index=0.81±0.03) than the conventional atlas-based segmentation method (0.72±0.04). Also as for segmentation accuracy which is measured in terms of the ratios of false positive and false negative, the proposed method (precision=0.76±0.04, recall=0.86±0.05) produced lower ratios than the conventional methods (0.73±0.05, 0.72±0.06) demonstrating its plausibility for accurate, robust and reliable segmentation of hippocampus. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Segmentation of head magnetic resonance image using self-mapping characteristic

    International Nuclear Information System (INIS)

    Madokoro, Hirokazu; Sato, Kazuhito; Ishii, Masaki; Kadowaki, Sakura

    2004-01-01

    In this paper, we proposed a segmentation method, for head magnetic resonance (MR) images. Our method used self mapping characteristic of a self-organization map (SOM), and it does not need the setting of the representative point by the operator. We considered the continuity and boundary in the brain tissues by the definition of the local block. In the evaluation experiment, we obtained the segmentation result of matching anatomical structure information. In addition, our method applied the clinical MR images, it was possible to obtain the effective and objective result for supporting the diagnosis of the brain atrophy by the doctor. (author)

  20. Influence of Chirality in Ordered Block Copolymer Phases

    Science.gov (United States)

    Prasad, Ishan; Grason, Gregory

    2015-03-01

    Block copolymers are known to assemble into rich spectrum of ordered phases, with many complex phases driven by asymmetry in copolymer architecture. Despite decades of study, the influence of intrinsic chirality on equilibrium mesophase assembly of block copolymers is not well understood and largely unexplored. Self-consistent field theory has played a major role in prediction of physical properties of polymeric systems. Only recently, a polar orientational self-consistent field (oSCF) approach was adopted to model chiral BCP having a thermodynamic preference for cholesteric ordering in chiral segments. We implement oSCF theory for chiral nematic copolymers, where segment orientations are characterized by quadrupolar chiral interactions, and focus our study on the thermodynamic stability of bi-continuous network morphologies, and the transfer of molecular chirality to mesoscale chirality of networks. Unique photonic properties observed in butterfly wings have been attributed to presence of chiral single-gyroid networks, this has made it an attractive target for chiral metamaterial design.

  1. Block design reconstruction skills: not a good candidate for an endophenotypic marker in autism research.

    Science.gov (United States)

    de Jonge, Maretha; Kemner, Chantal; Naber, Fabienne; van Engeland, Herman

    2009-04-01

    Superior performance on block design tasks is reported in autistic individuals, although it is not consistently found in high-functioning individuals or individuals with Asperger Syndrome. It is assumed to reflect weak central coherence: an underlying cognitive deficit, which might also be part of the genetic makeup of the disorder. We assessed block design reconstruction skills in high-functioning individuals with autism spectrum disorders (ASD) from multi-incidence families and in their parents. Performance was compared to relevant matched control groups. We used a task that was assumed to be highly sensitive to subtle performance differences. We did not find individuals with ASD to be significantly faster on this task than the matched control group, not even when the difference between reconstruction time of segmented and pre-segmented designs was compared. However, we found individuals with ASD to make fewer errors during the process of reconstruction which might indicate some dexterity in mental segmentation. However, parents of individuals with ASD did not perform better on the task than control parents. Therefore, based on our data, we conclude that mental segmentation ability as measured with a block design reconstruction task is not a neurocognitive marker or endophenotype useful in genetic studies.

  2. Physics of partially ionized plasmas

    CERN Document Server

    Krishan, Vinod

    2016-01-01

    Plasma is one of the four fundamental states of matter; the other three being solid, liquid and gas. Several components, such as molecular clouds, diffuse interstellar gas, the solar atmosphere, the Earth's ionosphere and laboratory plasmas, including fusion plasmas, constitute the partially ionized plasmas. This book discusses different aspects of partially ionized plasmas including multi-fluid description, equilibrium and types of waves. The discussion goes on to cover the reionization phase of the universe, along with a brief description of high discharge plasmas, tokomak plasmas and laser plasmas. Various elastic and inelastic collisions amongst the three particle species are also presented. In addition, the author demonstrates the novelty of partially ionized plasmas using many examples; for instance, in partially ionized plasma the magnetic induction is subjected to the ambipolar diffusion and the Hall effect, as well as the usual resistive dissipation. Also included is an observation of kinematic dynam...

  3. Partially massless fields during inflation

    Science.gov (United States)

    Baumann, Daniel; Goon, Garrett; Lee, Hayden; Pimentel, Guilherme L.

    2018-04-01

    The representation theory of de Sitter space allows for a category of partially massless particles which have no flat space analog, but could have existed during inflation. We study the couplings of these exotic particles to inflationary perturbations and determine the resulting signatures in cosmological correlators. When inflationary perturbations interact through the exchange of these fields, their correlation functions inherit scalings that cannot be mimicked by extra massive fields. We discuss in detail the squeezed limit of the tensor-scalar-scalar bispectrum, and show that certain partially massless fields can violate the tensor consistency relation of single-field inflation. We also consider the collapsed limit of the scalar trispectrum, and find that the exchange of partially massless fields enhances its magnitude, while giving no contribution to the scalar bispectrum. These characteristic signatures provide clean detection channels for partially massless fields during inflation.

  4. Scale-space for empty catheter segmentation in PCI fluoroscopic images.

    Science.gov (United States)

    Bacchuwar, Ketan; Cousty, Jean; Vaillant, Régis; Najman, Laurent

    2017-07-01

    In this article, we present a method for empty guiding catheter segmentation in fluoroscopic X-ray images. The guiding catheter, being a commonly visible landmark, its segmentation is an important and a difficult brick for Percutaneous Coronary Intervention (PCI) procedure modeling. In number of clinical situations, the catheter is empty and appears as a low contrasted structure with two parallel and partially disconnected edges. To segment it, we work on the level-set scale-space of image, the min tree, to extract curve blobs. We then propose a novel structural scale-space, a hierarchy built on these curve blobs. The deep connected component, i.e. the cluster of curve blobs on this hierarchy, that maximizes the likelihood to be an empty catheter is retained as final segmentation. We evaluate the performance of the algorithm on a database of 1250 fluoroscopic images from 6 patients. As a result, we obtain very good qualitative and quantitative segmentation performance, with mean precision and recall of 80.48 and 63.04% respectively. We develop a novel structural scale-space to segment a structured object, the empty catheter, in challenging situations where the information content is very sparse in the images. Fully-automatic empty catheter segmentation in X-ray fluoroscopic images is an important and preliminary step in PCI procedure modeling, as it aids in tagging the arrival and removal location of other interventional tools.

  5. Segmental Adenomyomatosis of Gallbladder: CT Assessment of the Patterns of Cholecystolithiasis

    International Nuclear Information System (INIS)

    Yoo, Yeon Hwa; Yu, Jeong Sik; Chung, Jae Joon; Kim, Joo Hee; Cho, Eun Suk; Kim, Dae Jung; Ahn, Jhii Hyun; Kim, Ki Whang

    2011-01-01

    To clarify the relationship between the pattern of cholecystolithiasis and the gross features of segmental adenomyomatosis of the gallbladder. Fifty-five consecutive patients with segmental adenomyomatosis with calcified gallbladder stones defined on CT were retrospectively analyzed in terms of (i) stone location (fundal vs. neck compartment) and (ii) size of the largest stone as a function of the extent of segmental mural thickening (type A, limited at the narrow segment; type B, partially extended in the fundal direction; type C, involving the entire fundal compartment). The extent of segmental mural thickening in patients with cholecystolithiasis was compared with a control group (n = 48) lacking stones. Stones were found more frequently in the fundal compartment in 48 patients compared to the neck compartment in 12 patients (p<0.001). The mean size of the largest stone in type C (5.4 ± 4.9 mm) was larger than in type A (2.3 ± 2.2 mm) (p=0.033). In patients with cholecystolithiasis, type C segmental thickening was predominant (69%) compared to the control group (42%) (p=0.012). In addition to a higher prevalence of stones, a wide extent of mural thickening combined with large stone size in the fundal compartment suggests the contribution of segmental adenomyomatosis to stone formation and chronic inflammation.

  6. Partial segmental thrombosis of the corpus cavernosum presenting with perineal pain.

    Science.gov (United States)

    Christodoulidou, Michelle; Parnham, Arie; Ramachandran, Navin; Muneer, Asif

    2016-11-22

    We describe the case of a man aged 43 years who presented with a 2-week history of a palpable lump in the right proximal penile shaft. This was preceded by a 6-month history of perineal pain, accompanied by erectile dysfunction. An urgent MRI scan of his penis identified a thrombus within the right crus and corpus of the penis. His thrombophilia screen was normal. The patient was started on oral anticoagulation and a phosphodiesterase inhibitor (PDE-5i) to prevent thrombus progression and maintain erectile function. At 5 months, the patients' symptoms had resolved and an MRI showed a reduction in the thrombus size. MRI is a useful imaging modality to diagnose a thrombus within the corpus cavernosum in patients presenting with a history of penile and perineal pain together with a palpable lump. The non-enhancement of the lesion helps to differentiate this from alternative rare lesions within the penis and perineum. 2016 BMJ Publishing Group Ltd.

  7. Unsupervised Performance Evaluation of Image Segmentation

    Directory of Open Access Journals (Sweden)

    Chabrier Sebastien

    2006-01-01

    Full Text Available We present in this paper a study of unsupervised evaluation criteria that enable the quantification of the quality of an image segmentation result. These evaluation criteria compute some statistics for each region or class in a segmentation result. Such an evaluation criterion can be useful for different applications: the comparison of segmentation results, the automatic choice of the best fitted parameters of a segmentation method for a given image, or the definition of new segmentation methods by optimization. We first present the state of art of unsupervised evaluation, and then, we compare six unsupervised evaluation criteria. For this comparative study, we use a database composed of 8400 synthetic gray-level images segmented in four different ways. Vinet's measure (correct classification rate is used as an objective criterion to compare the behavior of the different criteria. Finally, we present the experimental results on the segmentation evaluation of a few gray-level natural images.

  8. Efficient graph-cut tattoo segmentation

    Science.gov (United States)

    Kim, Joonsoo; Parra, Albert; Li, He; Delp, Edward J.

    2015-03-01

    Law enforcement is interested in exploiting tattoos as an information source to identify, track and prevent gang-related crimes. Many tattoo image retrieval systems have been described. In a retrieval system tattoo segmentation is an important step for retrieval accuracy since segmentation removes background information in a tattoo image. Existing segmentation methods do not extract the tattoo very well when the background includes textures and color similar to skin tones. In this paper we describe a tattoo segmentation approach by determining skin pixels in regions near the tattoo. In these regions graph-cut segmentation using a skin color model and a visual saliency map is used to find skin pixels. After segmentation we determine which set of skin pixels are connected with each other that form a closed contour including a tattoo. The regions surrounded by the closed contours are considered tattoo regions. Our method segments tattoos well when the background includes textures and color similar to skin.

  9. Metric Learning for Hyperspectral Image Segmentation

    Science.gov (United States)

    Bue, Brian D.; Thompson, David R.; Gilmore, Martha S.; Castano, Rebecca

    2011-01-01

    We present a metric learning approach to improve the performance of unsupervised hyperspectral image segmentation. Unsupervised spatial segmentation can assist both user visualization and automatic recognition of surface features. Analysts can use spatially-continuous segments to decrease noise levels and/or localize feature boundaries. However, existing segmentation methods use tasks-agnostic measures of similarity. Here we learn task-specific similarity measures from training data, improving segment fidelity to classes of interest. Multiclass Linear Discriminate Analysis produces a linear transform that optimally separates a labeled set of training classes. The defines a distance metric that generalized to a new scenes, enabling graph-based segmentation that emphasizes key spectral features. We describe tests based on data from the Compact Reconnaissance Imaging Spectrometer (CRISM) in which learned metrics improve segment homogeneity with respect to mineralogical classes.

  10. The FRJ-1 (MERLIN) research reactor: its main activity inventory has been removed by successful demolition of the reactor block

    International Nuclear Information System (INIS)

    Stahn, B.; Printz, R.; Matela, K.; Zehbe, C.; Poeppinghaus, J.; Cremer, J.

    2004-01-01

    The FRJ-1 (MERLIN) research reactor was decommissioned in 1985 after twenty-three years of operation. Demolition of the plant was begun in 1996. The article contains a survey of the demolition steps carried out so far within the framework of three partial permits. The main activity is the demolition of the reactor core structures as a precondition for subsequent measures to ensure clearance measurements of the building. The core structures are demolished which were exposed to high neutron fluxes during reactor operation and now show the highest activity and dose rate levels, except for the core internals. For demolition and disassembly of the metal structures in this part of the plant, the tools specially designed and made include a remotely operated sawing system and a pipe cutting system for internal segmentation of the beam lines. The universal demolition tool for use also above and beyond the concrete structures has been found to be a remotely controlled electrohydraulic demolition shovel. Spreading contamination in the course of the demolition work was avoided. One major reason for this success was the fact that no major airborne contamination existed at any time as a consequence of the quality of the material demolished and also of the consistent use of technical tools. While the reactor block was being demolished, an application for clearance measurement of the reactor hall and subsequent release from the scope of the Atomic Energy Act was filed as early as in mid-2003. The fourth partial permit covering these activities is expected to be issued in the spring of 2004. (orig.)

  11. Introduction to partial differential equations

    CERN Document Server

    Greenspan, Donald

    2000-01-01

    Designed for use in a one-semester course by seniors and beginning graduate students, this rigorous presentation explores practical methods of solving differential equations, plus the unifying theory underlying the mathematical superstructure. Topics include basic concepts, Fourier series, second-order partial differential equations, wave equation, potential equation, heat equation, approximate solution of partial differential equations, and more. Exercises appear at the ends of most chapters. 1961 edition.

  12. Adaptive local thresholding for robust nucleus segmentation utilizing shape priors

    Science.gov (United States)

    Wang, Xiuzhong; Srinivas, Chukka

    2016-03-01

    This paper describes a novel local thresholding method for foreground detection. First, a Canny edge detection method is used for initial edge detection. Then, tensor voting is applied on the initial edge pixels, using a nonsymmetric tensor field tailored to encode prior information about nucleus size, shape, and intensity spatial distribution. Tensor analysis is then performed to generate the saliency image and, based on that, the refined edge. Next, the image domain is divided into blocks. In each block, at least one foreground and one background pixel are sampled for each refined edge pixel. The saliency weighted foreground histogram and background histogram are then created. These two histograms are used to calculate a threshold by minimizing the background and foreground pixel classification error. The block-wise thresholds are then used to generate the threshold for each pixel via interpolation. Finally, the foreground is obtained by comparing the original image with the threshold image. The effective use of prior information, combined with robust techniques, results in far more reliable foreground detection, which leads to robust nucleus segmentation.

  13. Interferon Induced Focal Segmental Glomerulosclerosis

    Directory of Open Access Journals (Sweden)

    Yusuf Kayar

    2016-01-01

    Full Text Available Behçet’s disease is an inflammatory disease of unknown etiology which involves recurring oral and genital aphthous ulcers and ocular lesions as well as articular, vascular, and nervous system involvement. Focal segmental glomerulosclerosis (FSGS is usually seen in viral infections, immune deficiency syndrome, sickle cell anemia, and hyperfiltration and secondary to interferon therapy. Here, we present a case of FSGS identified with kidney biopsy in a patient who had been diagnosed with Behçet’s disease and received interferon-alpha treatment for uveitis and presented with acute renal failure and nephrotic syndrome associated with interferon.

  14. A contrario line segment detection

    CERN Document Server

    von Gioi, Rafael Grompone

    2014-01-01

    The reliable detection of low-level image structures is an old and still challenging problem in computer vision. This?book leads a detailed tour through the LSD algorithm, a line segment detector designed to be fully automatic. Based on the a contrario framework, the algorithm works efficiently without the need of any parameter tuning. The design criteria are thoroughly explained and the algorithm's good and bad results are illustrated on real and synthetic images. The issues involved, as well as the strategies used, are common to many geometrical structure detection problems and some possible

  15. Did Globalization Lead to Segmentation?

    DEFF Research Database (Denmark)

    Di Vaio, Gianfranco; Enflo, Kerstin Sofia

    Economic historians have stressed that income convergence was a key feature of the 'OECD-club' and that globalization was among the accelerating forces of this process in the long-run. This view has however been challenged, since it suffers from an ad hoc selection of countries. In the paper......, a mixture model is applied to a sample of 64 countries to endogenously analyze the cross-country growth behavior over the period 1870-2003. Results show that growth patterns were segmented in two worldwide regimes, the first one being characterized by convergence, and the other one denoted by divergence...

  16. Asymmetric PS-block-(PS-co-PB)-block-PS block copolymers: morphology formation and deformation behaviour

    International Nuclear Information System (INIS)

    Adhikari, Rameshwar; Huy, Trinh An; Buschnakowski, Matthias; Michler, Goerg H; Knoll, Konrad

    2004-01-01

    Morphology formation and deformation behaviour of asymmetric styrene/butadiene triblock copolymers (total polystyrene (PS) content ∼70%) consisting of PS outer blocks held apart by a styrene-co-butadiene random copolymer block (PS-co-PB) each were investigated. The techniques used were differential scanning calorimetry, transmission electron microscopy, uniaxial tensile testing and Fourier-transform infrared spectroscopy. A significant shift of the phase behaviour relative to that of a neat symmetric triblock copolymer was observed, which can be attributed to the asymmetric architecture and the presence of PS-co-PB as a soft block. The mechanical properties and the microdeformation phenomena were mainly controlled by the nature of their solid-state morphology. Independent of morphology type, the soft phase was found to deform to a significantly higher degree of orientation when compared with the hard phase

  17. Effect of image scaling and segmentation in digital rock characterisation

    Science.gov (United States)

    Jones, B. D.; Feng, Y. T.

    2016-04-01

    Digital material characterisation from microstructural geometry is an emerging field in computer simulation. For permeability characterisation, a variety of studies exist where the lattice Boltzmann method (LBM) has been used in conjunction with computed tomography (CT) imaging to simulate fluid flow through microscopic rock pores. While these previous works show that the technique is applicable, the use of binary image segmentation and the bounceback boundary condition results in a loss of grain surface definition when the modelled geometry is compared to the original CT image. We apply the immersed moving boundary (IMB) condition of Noble and Torczynski as a partial bounceback boundary condition which may be used to better represent the geometric definition provided by a CT image. The IMB condition is validated against published work on idealised porous geometries in both 2D and 3D. Following this, greyscale image segmentation is applied to a CT image of Diemelstadt sandstone. By varying the mapping of CT voxel densities to lattice sites, it is shown that binary image segmentation may underestimate the true permeability of the sample. A CUDA-C-based code, LBM-C, was developed specifically for this work and leverages GPU hardware in order to carry out computations.

  18. Associations between Family Adversity and Brain Volume in Adolescence: Manual vs. Automated Brain Segmentation Yields Different Results

    OpenAIRE

    Lyden, Hannah; Gimbel, Sarah I.; Del Piero, Larissa; Tsai, A. Bryna; Sachs, Matthew E.; Kaplan, Jonas T.; Margolin, Gayla; Saxbe, Darby

    2016-01-01

    Associations between brain structure and early adversity have been inconsistent in the literature. These inconsistencies may be partially due to methodological differences. Different methods of brain segmentation may produce different results, obscuring the relationship between early adversity and brain volume. Moreover, adolescence is a time of significant brain growth and certain brain areas have distinct rates of development, which may compromise the accuracy of automated segmentation appr...

  19. [Acrylic resin removable partial dentures].

    Science.gov (United States)

    de Baat, C; Witter, D J; Creugers, N H J

    2011-01-01

    An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of removable partial dentures, the acrylic resin removable partial denture has 3 favourable aspects: the economic aspect, its aesthetic quality and the ease with which it can be extended and adjusted. Disadvantages are an increased risk of caries developing, gingivitis, periodontal disease, denture stomatitis, alveolar bone reduction, tooth migration, triggering of the gag reflex and damage to the acrylic resin base. Present-day indications are ofa temporary or palliative nature or are motivated by economic factors. Special varieties of the acrylic resin removable partial denture are the spoon denture, the flexible denture fabricated of non-rigid acrylic resin, and the two-piece sectional denture. Furthermore, acrylic resin removable partial dentures can be supplied with clasps or reinforced by fibers or metal wires.

  20. Ultrasound-Guided Multiple Peripheral Nerve Blocks in a Superobese Patient

    Directory of Open Access Journals (Sweden)

    Alper Kilicaslan

    2014-01-01

    Full Text Available The number of obese patients has increased dramatically worldwide. Morbid obesity is associated with an increased incidence of medical comorbidities and restricts the application choices in anesthesiology. We report a successfully performed combined ultrasound-guided blockade of the femoral, tibial, and common peroneal nerve in a superobese patient. We present a case report of a 31-year-old, ASA-PS II, super obese man (190 kg, 180 cm, BMI: 58 kg/m2 admitted to the emergency department with a type II segmental tibia shaft fracture and ankle dislocation after a vehicle accident. After two failed spinal anesthesia attempts, we decided to apply a femoral block combined with a sciatic block. Femoral blocks were successfully performed with US guided in-plane technique. Separate blocks of the tibial and common peroneal nerves were planned after the sciatic nerve could not be located due to the thick subcutaneous tissue. We performed a tibial nerve block at 2 cm above the popliteal crease and common peroneal nerve at the level of the fibular head with US guided in-plane technique. The blocks were successful and no block-related complications were noted. Ultrasound guidance allows new approaches for multiple peripheral nerve blocks with low local anesthetic doses in obese patients.

  1. Synthesis of Fluorinated Amphiphilic Block Copolymers Based on PEGMA, HEMA, and MMA via ATRP and CuAAC Click Chemistry

    OpenAIRE

    Erol, Fatime Eren; Sinirlioglu, Deniz; Cosgun, Sedat; Muftuoglu, Ali Ekrem

    2014-01-01

    Synthesis of fluorinated amphiphilic block copolymers via atom transfer radical polymerization (ATRP) and Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition (CuAAC) was demonstrated. First, a PEGMA and MMA based block copolymer carrying multiple side-chain acetylene moieties on the hydrophobic segment for postfunctionalization was carried out. This involves the synthesis of a series of P(HEMA-co-MMA) random copolymers to be employed as macroinitiators in the controlled synthesis of P(HEMA-co-M...

  2. Main-chain supramolecular block copolymers.

    Science.gov (United States)

    Yang, Si Kyung; Ambade, Ashootosh V; Weck, Marcus

    2011-01-01

    Block copolymers are key building blocks for a variety of applications ranging from electronic devices to drug delivery. The material properties of block copolymers can be tuned and potentially improved by introducing noncovalent interactions in place of covalent linkages between polymeric blocks resulting in the formation of supramolecular block copolymers. Such materials combine the microphase separation behavior inherent to block copolymers with the responsiveness of supramolecular materials thereby affording dynamic and reversible materials. This tutorial review covers recent advances in main-chain supramolecular block copolymers and describes the design principles, synthetic approaches, advantages, and potential applications.

  3. Smart ampholytic ABC block copolypeptide

    Czech Academy of Sciences Publication Activity Database

    Schlaad, H.; Sun, J.; Černoch, Peter; Ruokolainen, J.

    2017-01-01

    Roč. 254, 20 August (2017), s. 79 ISSN 0065-7727. [ACS National Meeting & Exposition /254./. 20.08.2017-24.08.2017, Washington] Institutional support: RVO:61389013 Keywords : block copolypeptide * smart ampholytic Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science

  4. First Degree Pacemaker Exit Block

    Directory of Open Access Journals (Sweden)

    Johnson Francis

    2016-10-01

    Full Text Available Usually atrial and ventricular depolarizations follow soon after the pacemaker stimulus (spike on the ECG. But there can be an exit block due to fibrosis at the electrode - tissue interface at the lead tip. This can increase the delay between the spike and atrial or ventricular depolarization.

  5. Building Blocks for Personal Brands

    Science.gov (United States)

    Thomas, Lisa Carlucci

    2011-01-01

    In this article, the author discusses the four essential building blocks for personal brands: (1) name; (2) message; (3) channels; and (4) bridges. However, outstanding building materials can only take a person so far. The author emphasizes that vision, determination, faith, a sense of humor, and humility are also required.

  6. Thermo-responsive block copolymers

    NARCIS (Netherlands)

    Mocan Cetintas, Merve

    2017-01-01

    Block copolymers (BCPs) are remarkable materials because of their self-assembly behavior into nano-sized regular structures and high tunable properties. BCPs are in used various applications such as surfactants, nanolithography, biomedicine and nanoporous membranes. In these thesis, we aimed to

  7. Cervical plexus block for thyroidectomy

    African Journals Online (AJOL)

    Adele

    RESEARCH. Southern African Journal of Anaesthesia & Analgesia - November 2003 ... Cervical plexus block has also been found useful for thy- .... lar, transverse cervical and supraclavicular nerves. ... administration of midazolam and pentazocine as required. ... find out if there were postoperative complications specific to.

  8. [Correlation between the inspired fraction of oxygen, maternal partial oxygen pressure, and fetal partial oxygen pressure during cesarean section of normal pregnancies].

    Science.gov (United States)

    Castro, Carlos Henrique Viana de; Cruvinel, Marcos Guilherme Cunha; Carneiro, Fabiano Soares; Silva, Yerkes Pereira; Cabral, Antônio Carlos Vieira; Bessa, Roberto Cardoso

    2009-01-01

    Despite changes in pulmonary function, maternal oxygenation is maintained during obstetric regional blocks. But in those situations, the administration of supplementary oxygen to parturients is a common practice. Good fetal oxygenation is the main justification; however, this has not been proven. The objective of this randomized, prospective study was to test the hypothesis of whether maternal hyperoxia is correlated with an increase in fetal gasometric parameters in elective cesarean sections. Arterial blood gases of 20 parturients undergoing spinal block with different inspired fractions of oxygen were evaluated and correlated with fetal arterial blood gases. An increase in maternal inspired fraction of oxygen did not show any correlation with an increase of fetal partial oxygen pressure. Induction of maternal hyperoxia by the administration of supplementary oxygen did not increase fetal partial oxygen pressure. Fetal gasometric parameters did not change even when maternal parameters changed, induced by hyperoxia, during cesarean section under spinal block.

  9. Pathogenesis of Focal Segmental Glomerulosclerosis

    Directory of Open Access Journals (Sweden)

    Beom Jin Lim

    2016-11-01

    Full Text Available Focal segmental glomerulosclerosis (FSGS is characterized by focal and segmental obliteration of glomerular capillary tufts with increased matrix. FSGS is classified as collapsing, tip, cellular, perihilar and not otherwise specified variants according to the location and character of the sclerotic lesion. Primary or idiopathic FSGS is considered to be related to podocyte injury, and the pathogenesis of podocyte injury has been actively investigated. Several circulating factors affecting podocyte permeability barrier have been proposed, but not proven to cause FSGS. FSGS may also be caused by genetic alterations. These genes are mainly those regulating slit diaphragm structure, actin cytoskeleton of podocytes, and foot process structure. The mode of inheritance and age of onset are different according to the gene involved. Recently, the role of parietal epithelial cells (PECs has been highlighted. Podocytes and PECs have common mesenchymal progenitors, therefore, PECs could be a source of podocyte repopulation after podocyte injury. Activated PECs migrate along adhesion to the glomerular tuft and may also contribute to the progression of sclerosis. Markers of activated PECs, including CD44, could be used to distinguish FSGS from minimal change disease. The pathogenesis of FSGS is very complex; however, understanding basic mechanisms of podocyte injury is important not only for basic research, but also for daily diagnostic pathology practice.

  10. Laparoscopic Partial Hepatectomy of Focal Nodular Hyperplasia

    Directory of Open Access Journals (Sweden)

    Mayu Sakata

    2012-11-01

    Full Text Available Focal nodular hyperplasia is a benign liver lesion incidentally discovered with increasing frequency because of the proliferation of imaging studies. Radiographic characterization can diagnose this pathologic lesion and nonoperative therapy is the standard of care. However, surgical resection may be required for diagnostic reasons or symptomatic patients. Depending on the anatomic location of the lesion, biopsy and/or resection can be performed laparoscopically. We herein report the case of a 26-year-old Japanese woman with a hepatic tumor who required a medical examination. Her medical history was negative for alcohol abuse, oral contraceptive administration and trauma. Clinical examination showed no significant symptoms. Ultrasonography, computed tomography and magnetic resonance imaging showed a mass located in the left lateral segment of the liver with a diameter of about 40 mm. It was difficult to diagnose the tumor definitively from these imaging studies, so we performed laparoscopic partial hepatectomy with successive firing of endoscopic staplers. The histopathological diagnosis was focal nodular hyperplasia. Surgical procedures and postoperative course were uneventful and the patient was discharged from the hospital on postoperative day 5.

  11. Biologic comparison of partial breast irradiation protocols

    International Nuclear Information System (INIS)

    Rosenstein, Barry S.; Lymberis, Stella C.; Formenti, Silvia C.

    2004-01-01

    Purpose: To analyze the dose/fractionation schedules currently used in ongoing clinical trials of partial breast irradiation (PBI) by comparing their biologically effective dose (BED) values to those of three standard whole breast protocols commonly used after segmental mastectomy in the treatment of breast cancer. Methods and materials: The BED equation derived from the linear-quadratic model for radiation-induced cell killing was used to calculate the BEDs for three commonly used whole breast radiotherapy regimens, in addition to a variety of external beam radiotherapy, as well as high-dose-rate and low-dose-rate brachytherapy, PBI protocols. Results: The BED values of most PBI protocols resulted in tumor control BEDs roughly equivalent to a 50-Gy standard treatment, but consistently lower than the BEDs for regimens in which the tumor bed receives a total dose of either 60 Gy or 66 Gy. The BED values calculated for the acute radiation responses of erythema and desquamation were nearly all lower for the PBI schedules, and the late-response BEDs for most PBI regimens were in a similar range to the BEDs for the standard treatments. Conclusion: Biologically effective dose modeling raises the concern that inadequate doses might be delivered by PBI to ensure optimal in-field tumor control

  12. Optimal transformation for correcting partial volume averaging effects in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Soltanian-Zadeh, H.; Windham, J.P.; Yagle, A.E.

    1993-01-01

    Segmentation of a feature of interest while correcting for partial volume averaging effects is a major tool for identification of hidden abnormalities, fast and accurate volume calculation, and three-dimensional visualization in the field of magnetic resonance imaging (MRI). The authors present the optimal transformation for simultaneous segmentation of a desired feature and correction of partial volume averaging effects, while maximizing the signal-to-noise ratio (SNR) of the desired feature. It is proved that correction of partial volume averaging effects requires the removal of the interfering features from the scene. It is also proved that correction of partial volume averaging effects can be achieved merely by a linear transformation. It is finally shown that the optimal transformation matrix is easily obtained using the Gram-Schmidt orthogonalization procedure, which is numerically stable. Applications of the technique to MRI simulation, phantom, and brain images are shown. They show that in all cases the desired feature is segmented from the interfering features and partial volume information is visualized in the resulting transformed images

  13. Topology and Shape Control for Assemblies of Block Copolymer Blends in Solution

    KAUST Repository

    Moreno Chaparro, Nicolas; Nunes, Suzana Pereira; Peinemann, Klaus-Viktor; Calo, Victor M.

    2015-01-01

    We study binary blends of asymmetric diblock copolymers (AB/AC) in selective solvents with a mesoscale model. We investigate the morphological transitions induced by the concentration of the AC block copolymer and the difference in molecular weight between the AB and AC copolymers, when segments B and C exhibit hydrogen-bonding interactions. To the best of our knowledge, this is the first work modeling mixtures of block copolymers with large differences in molecular weight. The coassembly mechanism localizes the AC molecules at the interface of A and B domains and induces the swelling of the B-rich domains. The coil size of the large molecular weight block copolymer depends only on the concentration of the short block copolymer (AC or AB), regardless of the B–C interactions. However, the B–C interactions control the morphological transitions that occur in these blends.

  14. Topology and Shape Control for Assemblies of Block Copolymer Blends in Solution

    KAUST Repository

    Moreno Chaparro, Nicolas

    2015-10-27

    We study binary blends of asymmetric diblock copolymers (AB/AC) in selective solvents with a mesoscale model. We investigate the morphological transitions induced by the concentration of the AC block copolymer and the difference in molecular weight between the AB and AC copolymers, when segments B and C exhibit hydrogen-bonding interactions. To the best of our knowledge, this is the first work modeling mixtures of block copolymers with large differences in molecular weight. The coassembly mechanism localizes the AC molecules at the interface of A and B domains and induces the swelling of the B-rich domains. The coil size of the large molecular weight block copolymer depends only on the concentration of the short block copolymer (AC or AB), regardless of the B–C interactions. However, the B–C interactions control the morphological transitions that occur in these blends.

  15. Cutaneous Sensory Block Area, Muscle-Relaxing Effect, and Block Duration of the Transversus Abdominis Plane Block

    DEFF Research Database (Denmark)

    Støving, Kion; Rothe, Christian; Rosenstock, Charlotte V

    2015-01-01

    BACKGROUND AND OBJECTIVES: The transversus abdominis plane (TAP) block is a widely used nerve block. However, basic block characteristics are poorly described. The purpose of this study was to assess the cutaneous sensory block area, muscle-relaxing effect, and block duration. METHODS: Sixteen...... healthy volunteers were randomized to receive an ultrasound-guided unilateral TAP block with 20 mL 7.5 mg/mL ropivacaine and placebo on the contralateral side. Measurements were performed at baseline and 90 minutes after performing the block. Cutaneous sensory block area was mapped and separated...... into a medial and lateral part by a vertical line through the anterior superior iliac spine. We measured muscle thickness of the 3 lateral abdominal muscle layers with ultrasound in the relaxed state and during maximal voluntary muscle contraction. The volunteers reported the duration of the sensory block...

  16. Brain Tumor Image Segmentation in MRI Image

    Science.gov (United States)

    Peni Agustin Tjahyaningtijas, Hapsari

    2018-04-01

    Brain tumor segmentation plays an important role in medical image processing. Treatment of patients with brain tumors is highly dependent on early detection of these tumors. Early detection of brain tumors will improve the patient’s life chances. Diagnosis of brain tumors by experts usually use a manual segmentation that is difficult and time consuming because of the necessary automatic segmentation. Nowadays automatic segmentation is very populer and can be a solution to the problem of tumor brain segmentation with better performance. The purpose of this paper is to provide a review of MRI-based brain tumor segmentation methods. There are number of existing review papers, focusing on traditional methods for MRI-based brain tumor image segmentation. this paper, we focus on the recent trend of automatic segmentation in this field. First, an introduction to brain tumors and methods for brain tumor segmentation is given. Then, the state-of-the-art algorithms with a focus on recent trend of full automatic segmentaion are discussed. Finally, an assessment of the current state is presented and future developments to standardize MRI-based brain tumor segmentation methods into daily clinical routine are addressed.

  17. A new framework for interactive images segmentation

    International Nuclear Information System (INIS)

    Ashraf, M.; Sarim, M.; Shaikh, A.B.

    2017-01-01

    Image segmentation has become a widely studied research problem in image processing. There exist different graph based solutions for interactive image segmentation but the domain of image segmentation still needs persistent improvements. The segmentation quality of existing techniques generally depends on the manual input provided in beginning, therefore, these algorithms may not produce quality segmentation with initial seed labels provided by a novice user. In this work we investigated the use of cellular automata in image segmentation and proposed a new algorithm that follows a cellular automaton in label propagation. It incorporates both the pixel's local and global information in the segmentation process. We introduced the novel global constraints in automata evolution rules; hence proposed scheme of automata evolution is more effective than the automata based earlier evolution schemes. Global constraints are also effective in deceasing the sensitivity towards small changes made in manual input; therefore proposed approach is less dependent on label seed marks. It can produce the quality segmentation with modest user efforts. Segmentation results indicate that the proposed algorithm performs better than the earlier segmentation techniques. (author)

  18. Method to produce fuel element blocks for HTR reactors

    International Nuclear Information System (INIS)

    Hrovat, M.; Rachor, L.

    1977-01-01

    The patent claim relates to one partial step of the multi-stage pressing process in the production of fuel elements. A binder resin with a softening point at least 15 0 C but preferably 25-40 0 C above the melting point of the lubricant is proposed. The pressed block is expelled from the forging die in the temperature interval between the melting point of the lubricant and the softening point of the binder resin. The purpose of the invention is that the pressed fuel element blocks are expelled from the machine tool without damage at a pressure low enough to protect the mechanical integrity of the coated fuel particles or fertile particles. (UA) [de

  19. Heat-transfer in a partially-blocked sodium-cooled rod bundle

    International Nuclear Information System (INIS)

    Han, J.T.

    1979-01-01

    Heat transfer coefficients were experimentally determined for 31-rod sodium-cooled bundle with a 6-subchannel central blockage. The Nusselt number is presented as a function of the Peclet number for both the free flow region undisturbed by the blockage and the wake region immediately downstream of the blockage. Results are compared with the existing correlations for liquid metals. The heat transfer coefficient was generally higher in the unblocked free flow region than in the wake region. A leak at the blockage improved the heat transfer coefficient in the wake region

  20. Thermal-hydraulic of partially blocked fuel subassembly with porous media

    International Nuclear Information System (INIS)

    Nagata, Takemitsu; Ohshima, Hiroyuki

    2000-10-01

    The analysis code for investigations of local subassembly phenomena, which has been recognized as an issue of local subassembly accidents, has been required and developed at JNC. It is desirable for the analysis code to be applicable to various blockage conditions and random position of the blockage formation and to evaluate conservatively on the safety assessment with high accuracy. In this study, for the purpose of verifying the application and issues of the subchannel analysis code ASFRE-IV which evaluates thermal hydraulic phenomena in the porous blockage regions, the ASFRE-IV validation analysis was carried out on the basis of the data of an experiment investigation on a local porous blockage in a fuel subassembly performed by Reactor Engineering Groop, O-arai Engineering Center, JNC. Calculational results indicated that ASFRE-IV could reproduce the coolant temperature profile in a fuel subassembly and the peak temperature in the local subchannel conservatively. (author)

  1. A new user-assisted segmentation and tracking technique for an object-based video editing system

    Science.gov (United States)

    Yu, Hong Y.; Hong, Sung-Hoon; Lee, Mike M.; Choi, Jae-Gark

    2004-03-01

    This paper presents a semi-automatic segmentation method which can be used to generate video object plane (VOP) for object based coding scheme and multimedia authoring environment. Semi-automatic segmentation can be considered as a user-assisted segmentation technique. A user can initially mark objects of interest around the object boundaries and then the user-guided and selected objects are continuously separated from the unselected areas through time evolution in the image sequences. The proposed segmentation method consists of two processing steps: partially manual intra-frame segmentation and fully automatic inter-frame segmentation. The intra-frame segmentation incorporates user-assistance to define the meaningful complete visual object of interest to be segmentation and decides precise object boundary. The inter-frame segmentation involves boundary and region tracking to obtain temporal coherence of moving object based on the object boundary information of previous frame. The proposed method shows stable efficient results that could be suitable for many digital video applications such as multimedia contents authoring, content based coding and indexing. Based on these results, we have developed objects based video editing system with several convenient editing functions.

  2. Evaluation of Seismic Behaviors of Partially Deteriorated Reinforced Concrete Circular Columns Retrofitted with CFRP

    Directory of Open Access Journals (Sweden)

    Dongxu Hou

    2014-01-01

    Full Text Available Deficiency of the concrete strength in some regions of reinforced concrete (RC columns in practice may weaken the seismic behaviors of columns. Its effects on RC columns should be well understood. This paper aims to investigate the influences of deteriorated segment on the seismic behaviors of partially deteriorated RC columns and attempts to recover the seismic behaviors of partially deteriorated columns with Carbon Fiber Reinforced Polymer (CFRP composites. A finite element analysis was carried out to simulate the seismic behaviors of CFRP-confined partially deteriorated RC columns. The numerical results were verified by the laboratory tests of six specimens. Based on the finite element results, the failure location of partially deteriorated columns in an earthquake was predicted, and the effectiveness of CFRP retrofitted on partially deteriorated columns was evaluated.

  3. On the Eigenvalues and Eigenvectors of Block Triangular Preconditioned Block Matrices

    KAUST Repository

    Pestana, Jennifer

    2014-01-01

    Block lower triangular matrices and block upper triangular matrices are popular preconditioners for 2×2 block matrices. In this note we show that a block lower triangular preconditioner gives the same spectrum as a block upper triangular preconditioner and that the eigenvectors of the two preconditioned matrices are related. © 2014 Society for Industrial and Applied Mathematics.

  4. Parachute technique for partial penectomy

    Directory of Open Access Journals (Sweden)

    Fernando Korkes

    2010-04-01

    Full Text Available PURPOSE: Penile carcinoma is a rare but mutilating malignancy. In this context, partial penectomy is the most commonly applied approach for best oncological results. We herein propose a simple modification of the classic technique of partial penectomy, for better cosmetic and functional results. TECHNIQUE: If partial penectomy is indicated, the present technique can bring additional benefits. Different from classical technique, the urethra is spatulated only ventrally. An inverted "V" skin flap with 0.5 cm of extension is sectioned ventrally. The suture is performed with vicryl 4-0 in a "parachute" fashion, beginning from the ventral portion of the urethra and the "V" flap, followed by the "V" flap angles and than by the dorsal portion of the penis. After completion of the suture, a Foley catheter and light dressing are placed for 24 hours. CONCLUSIONS: Several complex reconstructive techniques have been previously proposed, but normally require specific surgical abilities, adequate patient selection and staged procedures. We believe that these reconstructive techniques are very useful in some specific subsets of patients. However, the technique herein proposed is a simple alternative that can be applied to all men after a partial penectomy, and takes the same amount of time as that in the classic technique. In conclusion, the "parachute" technique for penile reconstruction after partial amputation not only improves the appearance of the penis, but also maintains an adequate function.

  5. Locally excitatory, globally inhibitory oscillator networks: theory and application to scene segmentation

    Science.gov (United States)

    Wang, DeLiang; Terman, David

    1995-01-01

    A novel class of locally excitatory, globally inhibitory oscillator networks (LEGION) is proposed and investigated analytically and by computer simulation. The model of each oscillator corresponds to a standard relaxation oscillator with two time scales. The network exhibits a mechanism of selective gating, whereby an oscillator jumping up to its active phase rapidly recruits the oscillators stimulated by the same pattern, while preventing other oscillators from jumping up. We show analytically that with the selective gating mechanism the network rapidly achieves both synchronization within blocks of oscillators that are stimulated by connected regions and desynchronization between different blocks. Computer simulations demonstrate LEGION's promising ability for segmenting multiple input patterns in real time. This model lays a physical foundation for the oscillatory correlation theory of feature binding, and may provide an effective computational framework for scene segmentation and figure/ground segregation.

  6. Cooperative Interactions between 480 kDa Ankyrin-G and EB proteins assemble the axon initial segment

    NARCIS (Netherlands)

    Fréal, Amélie|info:eu-repo/dai/nl/412516721; Fassier, Coralie; Le Bras, Barbara; Bullier, Erika; de Gois, Stéphanie; Hazan, Jamilé; Hoogenraad, Casper C.|info:eu-repo/dai/nl/227263502; Couraud, François

    2016-01-01

    The axon initial segment (AIS) is required for generating action potentials and maintaining neuronal polarity. Significant progress has been made in deciphering the basic building blocks composing the AIS, but the underlying mechanisms required for AIS formation remains unclear. The scaffolding

  7. Whole vertebral bone segmentation method with a statistical intensity-shape model based approach

    Science.gov (United States)

    Hanaoka, Shouhei; Fritscher, Karl; Schuler, Benedikt; Masutani, Yoshitaka; Hayashi, Naoto; Ohtomo, Kuni; Schubert, Rainer

    2011-03-01

    An automatic segmentation algorithm for the vertebrae in human body CT images is presented. Especially we focused on constructing and utilizing 4 different statistical intensity-shape combined models for the cervical, upper / lower thoracic and lumbar vertebrae, respectively. For this purpose, two previously reported methods were combined: a deformable model-based initial segmentation method and a statistical shape-intensity model-based precise segmentation method. The former is used as a pre-processing to detect the position and orientation of each vertebra, which determines the initial condition for the latter precise segmentation method. The precise segmentation method needs prior knowledge on both the intensities and the shapes of the objects. After PCA analysis of such shape-intensity expressions obtained from training image sets, vertebrae were parametrically modeled as a linear combination of the principal component vectors. The segmentation of each target vertebra was performed as fitting of this parametric model to the target image by maximum a posteriori estimation, combined with the geodesic active contour method. In the experimental result by using 10 cases, the initial segmentation was successful in 6 cases and only partially failed in 4 cases (2 in the cervical area and 2 in the lumbo-sacral). In the precise segmentation, the mean error distances were 2.078, 1.416, 0.777, 0.939 mm for cervical, upper and lower thoracic, lumbar spines, respectively. In conclusion, our automatic segmentation algorithm for the vertebrae in human body CT images showed a fair performance for cervical, thoracic and lumbar vertebrae.

  8. Emplacement of small and large buffer blocks

    International Nuclear Information System (INIS)

    Saari, H.; Nikula, M.; Suikki, M.

    2010-05-01

    The report describes emplacement of a buffer structure encircling a spent fuel canister to be deposited in a vertical hole. The report deals with installability of various size blocks and with an emplacement gear, as well as evaluates the achieved quality of emplacement and the time needed for installing the buffer. Two block assembly of unequal size were chosen for examination. A first option involved small blocks, the use of which resulted in a buffer structure consisting of small sector blocks 200 mm in height. A second option involved large blocks, resulting in a buffer structure which consists of eight blocks. In these tests, the material chosen for both block options was concrete instead of bentonite. The emplacement test was a three-phase process. A first phase included stacking a two meter high buffer structure with small blocks for ensuring the operation of test equipment and blocks. A second phase included installing buffer structures with both block options to a height matching that of a canister-encircling cylindrical component. A third phase included testing also the installability of blocks to be placed above the canister by using small blocks. In emplacement tests, special attention was paid to the installability of blocks as well as to the time required for emplacement. Lifters for both blocks worked well. Due to the mass to be lifted, the lifter for large blocks had a more heavy-duty frame structure (and other lifting gear). The employed lifters were suspended in the tests on a single steel wire rope. Stacking was managed with both block sizes at adequate precision and stacked-up towers were steady. The stacking of large blocks was considerably faster. Therefore it is probably that the overall handling of the large blocks will be more convenient at a final disposal site. From the standpoint of reliability in lifting, the small blocks were safer to install above the canister. In large blocks, there are strict shape-related requirements which are

  9. Molecular Mobility in Phase Segregated Bottlebrush Block Copolymer Melts

    Science.gov (United States)

    Yavitt, Benjamin; Gai, Yue; Song, Dongpo; Winter, H. Henning; Watkins, James

    We investigate the linear viscoelastic behavior of poly(styrene)-block-poly(ethylene oxide) (PS-b-PEO) brush block copolymer (BBCP) materials over a range of vol. fractions and with side chain lengths below the entanglement molecular weights. The high chain mobility of the brush architecture results in rapid micro-phase segregation of the brush copolymer segments, which occurs during thermal annealing at mild temperatures. Master curves of the dynamic moduli were obtained by time-temperature superposition. The reduced degree of chain entanglements leads to a unique liquid-like rheology similar to that of bottlebrush homopolymers, even in the phase segregated state. We also explore the alignment of phase segregated domains at exceptionally low strain amplitudes (γ = 0.01) and mild processing temperatures using small angle X-ray scattering (SAXS). Domain orientation occurred readily at strains within the linear viscoelastic regime without noticeable effect on the moduli. This interplay of high molecular mobility and rapid phase segregation that are exhibited simultaneously in BBCPs is in contrast to the behavior of conventional linear block copolymer (LBCP) analogs and opens up new possibilities for processing BBCP materials for a wide range of nanotechnology applications. NSF Center for Hierarchical Manufacturing at the University of Massachusetts, Amherst (CMMI-1025020).

  10. A framework for automatic segmentation in three dimensions of microstructural tomography data

    DEFF Research Database (Denmark)

    Jørgensen, Peter Stanley; Hansen, Karin Vels; Larsen, Rasmus

    2010-01-01

    Routine use of quantitative three dimensional analysis of material microstructure by in particular, focused ion beam (FIB) serial sectioning is generally restricted by the time consuming task of manually delineating structures within each image slice or the quality of manual and automatic...... segmentation schemes. We present here a framework for performing automatic segmentation of complex microstructures using a level set method. The technique is based on numerical approximations to partial differential equations to evolve a 3D surface to capture the phase boundaries. Vector fields derived from...

  11. Hierarchical image segmentation for learning object priors

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Lakshman [Los Alamos National Laboratory; Yang, Xingwei [TEMPLE UNIV.; Latecki, Longin J [TEMPLE UNIV.; Li, Nan [TEMPLE UNIV.

    2010-11-10

    The proposed segmentation approach naturally combines experience based and image based information. The experience based information is obtained by training a classifier for each object class. For a given test image, the result of each classifier is represented as a probability map. The final segmentation is obtained with a hierarchial image segmentation algorithm that considers both the probability maps and the image features such as color and edge strength. We also utilize image region hierarchy to obtain not only local but also semi-global features as input to the classifiers. Moreover, to get robust probability maps, we take into account the region context information by averaging the probability maps over different levels of the hierarchical segmentation algorithm. The obtained segmentation results are superior to the state-of-the-art supervised image segmentation algorithms.

  12. Image Segmentation Using Minimum Spanning Tree

    Science.gov (United States)

    Dewi, M. P.; Armiati, A.; Alvini, S.

    2018-04-01

    This research aim to segmented the digital image. The process of segmentation is to separate the object from the background. So the main object can be processed for the other purposes. Along with the development of technology in digital image processing application, the segmentation process becomes increasingly necessary. The segmented image which is the result of the segmentation process should accurate due to the next process need the interpretation of the information on the image. This article discussed the application of minimum spanning tree on graph in segmentation process of digital image. This method is able to separate an object from the background and the image will change to be the binary images. In this case, the object that being the focus is set in white, while the background is black or otherwise.

  13. Linked supramolecular building blocks for enhanced cluster formation

    DEFF Research Database (Denmark)

    McLellan, Ross; Palacios, Maria A.; Beavers, Christine M.

    2015-01-01

    the complex assembly process. The ability to covalently link calix[4]arenes at the methylene bridge provides significantly improved control over the introduction of different metal centres to resulting cluster motifs. Clusters assembled from bis-calix[4]-arenes and transition metal ions or 3d-4 f combinations......(Figure Presented). Methylene-bridged calix[4]arenes have emerged as extremely versatile ligand supports in the formation of new polymetallic clusters possessing fascinating magnetic properties. Metal ion binding rules established for this building block allow one to partially rationalise...

  14. Partial Transposition on Bipartite System

    International Nuclear Information System (INIS)

    Xi-Jun, Ren; Yong-Jian, Han; Yu-Chun, Wu; Guang-Can, Guo

    2008-01-01

    Many properties of partial transposition are unclear as yet. Here we carefully consider the number of the negative eigenvalues of ρ T (ρ's partial transposition) when ρ is a two-partite state. There is strong evidence to show that the number of negative eigenvalues of ρ T is N(N − 1)/2 at most when ρ is a state in Hilbert space C N C N . For the special case, the 2 × 2 system, we use this result to give a partial proof of the conjecture |ρ T | T ≥ 0. We find that this conjecture is strongly connected with the entanglement of the state corresponding to the negative eigenvalue of ρ T or the negative entropy of ρ

  15. Partial volume effect in MRI

    International Nuclear Information System (INIS)

    Maeda, Munehiro; Yoshiya, Kazuhiko; Suzuki, Eiji

    1989-01-01

    According to the direction and the thickness of the imaging slice in tomography, the border between the tissues becomes unclear (partial volume effect). In the present MRI experiment, we examined border area between fat and water components using phantom in order to investigate the partial volume effect in MRI. In spin echo sequences, the intensity of the border area showed a linear relationship with composition of fat and water. Whereas, in inversion recovery and field echo sequences, we found the parameters to produce an extremely low intensity area at the border region between fat and water. This low intensity area was explained by cancellation of NMR signals from fat and water due to the difference in the direction of magnetic vectors. Clinically, partial volume effect can cause of mis-evaluation of walls, small nodules, tumor capsules and the tumor invasion in the use of inversion recovery and field echo sequences. (author)

  16. Partially composite Goldstone Higgs boson

    DEFF Research Database (Denmark)

    Alanne, Tommi; Franzosi, Diogo Buarque; Frandsen, Mads T.

    2017-01-01

    We consider a model of dynamical electroweak symmetry breaking with a partially composite Goldstone Higgs boson. The model is based on a strongly interacting fermionic sector coupled to a fundamental scalar sector via Yukawa interactions. The SU(4)×SU(4) global symmetry of these two sectors...... is broken to a single SU(4) via Yukawa interactions. Electroweak symmetry breaking is dynamically induced by condensation due to the strong interactions in the new fermionic sector which further breaks the global symmetry SU(4)→Sp(4). The Higgs boson arises as a partially composite state which is an exact...... Goldstone boson in the limit where SM interactions are turned off. Terms breaking the SU(4) global symmetry explicitly generate a mass for the Goldstone Higgs boson. The model realizes in different limits both (partially) composite Higgs and (bosonic) technicolor models, thereby providing a convenient...

  17. Landsliding in partially saturated materials

    Science.gov (United States)

    Godt, J.W.; Baum, R.L.; Lu, N.

    2009-01-01

    [1] Rainfall-induced landslides are pervasive in hillslope environments around the world and among the most costly and deadly natural hazards. However, capturing their occurrence with scientific instrumentation in a natural setting is extremely rare. The prevailing thinking on landslide initiation, particularly for those landslides that occur under intense precipitation, is that the failure surface is saturated and has positive pore-water pressures acting on it. Most analytic methods used for landslide hazard assessment are based on the above perception and assume that the failure surface is located beneath a water table. By monitoring the pore water and soil suction response to rainfall, we observed shallow landslide occurrence under partially saturated conditions for the first time in a natural setting. We show that the partially saturated shallow landslide at this site is predictable using measured soil suction and water content and a novel unified effective stress concept for partially saturated earth materials. Copyright 2009 by the American Geophysical Union.

  18. Toxic Anterior Segment Syndrome (TASS

    Directory of Open Access Journals (Sweden)

    Özlem Öner

    2011-12-01

    Full Text Available Toxic anterior segment syndrome (TASS is a sterile intraocular inflammation caused by noninfectious substances, resulting in extensive toxic damage to the intraocular tissues. Possible etiologic factors of TASS include surgical trauma, bacterial endotoxin, intraocular solutions with inappropriate pH and osmolality, preservatives, denatured ophthalmic viscosurgical devices (OVD, inadequate sterilization, cleaning and rinsing of surgical devices, intraocular lenses, polishing and sterilizing compounds which are related to intraocular lenses. The characteristic signs and symptoms such as blurred vision, corneal edema, hypopyon and nonreactive pupil usually occur 24 hours after the cataract surgery. The differential diagnosis of TASS from infectious endophthalmitis is important. The main treatment for TASS formation is prevention. TASS is a cataract surgery complication that is more commonly seen nowadays. In this article, the possible underlying causes as well as treatment and prevention methods of TASS are summarized. (Turk J Oph thal mol 2011; 41: 407-13

  19. UAV PHOTOGRAMMETRY: BLOCK TRIANGULATION COMPARISONS

    Directory of Open Access Journals (Sweden)

    R. Gini

    2013-08-01

    Full Text Available UAVs systems represent a flexible technology able to collect a big amount of high resolution information, both for metric and interpretation uses. In the frame of experimental tests carried out at Dept. ICA of Politecnico di Milano to validate vector-sensor systems and to assess metric accuracies of images acquired by UAVs, a block of photos taken by a fixed wing system is triangulated with several software. The test field is a rural area included in an Italian Park ("Parco Adda Nord", useful to study flight and imagery performances on buildings, roads, cultivated and uncultivated vegetation. The UAV SenseFly, equipped with a camera Canon Ixus 220HS, flew autonomously over the area at a height of 130 m yielding a block of 49 images divided in 5 strips. Sixteen pre-signalized Ground Control Points, surveyed in the area through GPS (NRTK survey, allowed the referencing of the block and accuracy analyses. Approximate values for exterior orientation parameters (positions and attitudes were recorded by the flight control system. The block was processed with several software: Erdas-LPS, EyeDEA (Univ. of Parma, Agisoft Photoscan, Pix4UAV, in assisted or automatic way. Results comparisons are given in terms of differences among digital surface models, differences in orientation parameters and accuracies, when available. Moreover, image and ground point coordinates obtained by the various software were independently used as initial values in a comparative adjustment made by scientific in-house software, which can apply constraints to evaluate the effectiveness of different methods of point extraction and accuracies on ground check points.

  20. Communication with market segments - travel agencies' perspective

    OpenAIRE

    Lorena Bašan; Jasmina Dlačić; Željko Trezner

    2013-01-01

    Purpose – The purpose of this paper is to research the travel agencies’ communication with market segments. Communication with market segments takes into account marketing communication means as well as the implementation of different business orientations. Design – Special emphasis is placed on the use of different marketing communication means and their efficiency. Research also explores business orientation adaptation when approaching different market segments. Methodology – In explo...