Reminiscences Of The First His Bundle Electrography In India
2002-01-01
We spent two hectic years in AIIMS in 1972 and ''73 while undergoing our training for DM Cardiology. Dr Rajan Manjuran and myself were the two candidates and we worked day and night, but thoroughly enjoyed it as it was so exciting and educative. The cutting edge remarks by the inimitable Professor Sujoy B Roy, the meticulous precision of Prof M.L.Bhatia and the tender auscultatory sessions on infants with Prof Raj Tandon all are still fresh in mind. Another fascinating aspect of those days w...
[Experience with ablation of the bundle of His using electrical discharge].
Lukl, J; Cernosek, B; Heinc, P
1990-01-01
Ablation of the bundle of His by an electric discharge was made in 10 patients (average age 64 years, range 48-80) unsuccessfully treated with 3-14 antiarrhythmic drugs or their combinations (average 8.7) on account of supraventricular tachycardia occurring repeatedly for 3-44 years (average 12.5 years). By means of a bipolar electrode inserted into the area of the bundle of His a nonsynchronized defibrillation discharge with a mean energy of 323 J (40-380) was administered. On average 2.9 discharges were used (1-9) per patient, in 1-3 sessions. The patients were followed up for a period of 15.3 months (10-19). Permanent complete a-v block was achieved in 6 patients, the remaining 4 patients are also free from complaints with have antiarrhythmic treatment. To all patients a pacemaker was implanted, four times "physiological" stimulation was used. One month after the operation the authors observed once the development of a transient phatic disorder and once the slow development of cardiac tamponade in conjunction with anticoagulant treatment, resolved by pericardial puncture. Ablation of the bundle of His by a defibrillation discharge is thus in carefully selected patients a highly effective method of treatment of stubborn supraventricular tachycardias. PMID:2327082
Intra-His bundle block: clinical, electrocardiographic, and electrophysiologic characteristics
Andréa Eduardo M.; Atié Jacob; Maciel Washington A.; Oliveira Jr Nilson A. de; Camanho Luiz Eduardo; Belo Luís Gustavo; Carvalho Hecio Affonso de; Siqueira Leonardo; Saad Eduardo; Venancio Ana Claudia
2002-01-01
OBJECTIVE: To assess the clinical, electrocardiographic, and electrophysiologic characteristics of patients (pt) with intra-His bundle block undergoing an electrophysiologic study (EPS). METHODS: We analyzed the characteristics of 16 pt with second-degree atrioventricular block and symptoms of syncope or dyspnea, or both, undergoing conventional EPS. RESULTS: Intra-His bundle block was documented in 16 pt during an EPS. In 15 (94%) pt, the atrioventricular block was recorded in sinus rhythm; ...
International Nuclear Information System (INIS)
The increase of bundle supply has become widespread in several sectors (for instance in telecommunications and energy fields). This paper review relates strategic aspects of bundling. The main purpose of this paper is to analyze profitability of bundling strategies according to the degree of competition and the characteristics of goods. Moreover, bundling can be used as price discrimination tool, screening device or entry barriers. In monopoly case bundling strategy is efficient to sort consumers in different categories in order to capture a maximum of surplus. However, when competition increases, the profitability on bundling strategies depends on correlation of consumers' reservations values. (author)
Restrictions of stable bundles
Balaji, V
2011-01-01
The Mehta-Ramanathan theorem ensures that the restriction of a stable vector bundle to a sufficiently high degree complete intersection curve is again stable. We improve the bounds for the "sufficiently high degree" and propose a possibly optimal conjecture.
Dynamics of flagellar bundling
Janssen, Pieter; Graham, Michael
2010-11-01
Flagella are long thin appendages of microscopic organisms used for propulsion in low-Reynolds environments. For E. coli the flagella are driven by a molecular motor, which rotates the flagella in a counter-clockwise motion (CCM). When in a forward swimming motion, all flagella bundle up. If a motor reverses rotation direction, the flagella unbundle and the cell makes a tumbling motion. When all motors turn in the same CC direction again, the flagella bundle up, and forward swimming continues. To investigate the bundling, we consider two flexible helices next to each other, as well as several flagella attached to a spherical body. Each helix is modeled as several prolate spheroids connected at the tips by springs. For hydrodynamic interactions, we consider the flagella to made up of point forces, while the finite size of the body is incorporated via Fax'en's laws. We show that synchronization occurs quickly relative to the bundling process. For flagella next to each other, the initial deflection is generated by rotlet interactions generated by the rotating helices. At longer times, simulations show the flagella only wrap once around each other, but only for flagella that are closer than about 4 helix radii. Finally, we show a run-and-tumble motion of the body with attached flagella.
Directory of Open Access Journals (Sweden)
D. A. Robbins
1994-12-01
Full Text Available We study bundles of Banach algebras ÃÂ€:AÃ¢Â†Â’X, where each fiber Ax=ÃÂ€Ã¢ÂˆÂ’1({x} is a Banach algebra and X is a compact Hausdorff space. In the case where all fibers are commutative, we investigate how the Gelfand representation of the section space algebra ÃŽÂ“(ÃÂ€ relates to the Gelfand representation of the fibers. In the general case, we investigate how adjoining an identity to the bundle ÃÂ€:AÃ¢Â†Â’X relates to the standard adjunction of identities to the fibers.
Cassou-Nogues, Ph.; Erez, B.; Taylor, M. J.
2004-01-01
We establish comparison results between the Hasse-Witt invariants w_t(E) of a symmetric bundle E over a scheme and the invariants of one of its twists E_{\\alpha}. For general twists we describe the difference between w_t(E) and w_t(E_{\\alpha}) up to terms of degree 3. Next we consider a special kind of twist, which has been studied by A. Fr\\"ohlich. This arises from twisting by a cocycle obtained from an orthogonal representation. We show how to explicitly describe the twist for representatio...
Structure of the acrosomal bundle.
Schmid, Michael F; Sherman, Michael B; Matsudaira, Paul; Chiu, Wah
2004-09-01
In the unactivated Limulus sperm, a 60- micro m-long bundle of actin filaments crosslinked by the protein scruin is bent and twisted into a coil around the base of the nucleus. At fertilization, the bundle uncoils and fully extends in five seconds to support a finger of membrane known as the acrosomal process. This biological spring is powered by stored elastic energy and does not require the action of motor proteins or actin polymerization. In a 9.5-A electron cryomicroscopic structure of the extended bundle, we show that twist, tilt and rotation of actin-scruin subunits deviate widely from a 'standard' F-actin filament. This variability in structural organization allows filaments to pack into a highly ordered and rigid bundle in the extended state and suggests a mechanism for storing and releasing energy between coiled and extended states without disassembly. PMID:15343340
Cohomology of line bundles: Applications
Blumenhagen, Ralph; Jurke, Benjamin; Rahn, Thorsten; Roschy, Helmut
2012-01-01
Massless modes of both heterotic and Type II string compactifications on compact manifolds are determined by vector bundle valued cohomology classes. Various applications of our recent algorithm for the computation of line bundle valued cohomology classes over toric varieties are presented. For the heterotic string, the prime examples are so-called monad constructions on Calabi-Yau manifolds. In the context of Type II orientifolds, one often needs to compute cohomology for line bundles on finite group action coset spaces, necessitating us to generalize our algorithm to this case. Moreover, we exemplify that the different terms in Batyrev's formula and its generalizations can be given a one-to-one cohomological interpretation. Furthermore, we derive a combinatorial closed form expression for two Hodge numbers of a codimension two Calabi-Yau fourfold.
Failure properties of fiber bundle models
Pradhan, Srutarshi; Chakrabarti, Bikas K.
2003-01-01
We study the failure properties of fiber bundles when continuous rupture goes on due to the application of external load on the bundles. We take the two extreme models: equal load sharing model (democratic fiber bundles) and local load sharing model. The strength of the fibers are assumed to be distributed randomly within a finite interval. The democratic fiber bundles show a solvable phase transition at a critical stress (load per fiber). The dynamic critical behavior is obtained analyticall...
On Volumes of Arithmetic Line Bundles
Yuan, Xinyi
2008-01-01
We show an arithmetic generalization of the recent work of Lazarsfeld-Mustata which uses Okounkov bodies to study linear series of line bundles. As applications, we derive a log-concavity inequality on volumes of arithmetic line bundles and an arithmetic Fujita approximation theorem for big line bundles.
Strategic and welfare implications of bundling
DEFF Research Database (Denmark)
Martin, Stephen
1999-01-01
A standard oligopoly model of bundling shows that bundling by a firm with a monopoly over one product has a strategic effect because it changes the substitution relationships between the goods among which consumers choose. Bundling in appropriate proportions is privately profitable, reduces rivals...
Model of turbine blades bundles
Czech Academy of Sciences Publication Activity Database
Půst, Ladislav; Pešek, Luděk
Prague : Institute of Thermomechanics, Academy of Sciences of the Czech Republic, v. v. i., 2013 - (Zolotarev, I.), s. 467-477 ISBN 978-80-87012-47-5. ISSN 1805-8256. [Engineering Mechanics 2013 /19./. Svratka (CZ), 13.05.2013-16.05.2013] R&D Projects: GA ČR GA101/09/1166 Institutional support: RVO:61388998 Keywords : free and forced vibrations * eigenmodes * mathematical model * bundle of blades Subject RIV: BI - Acoustics
Model of turbine blades bundles
Czech Academy of Sciences Publication Activity Database
Půst, Ladislav; Pešek, Luděk
Praha : Insitute of Thermomechanics ASCR, v. v. i., 2013 - (Zolotarev, I.). s. 125-126 ISBN 978-80-87012-46-8. ISSN 1805-8248. [Engineering Mechanics 2013 /19./. 13.05.2013-16.05.2013, Svratka] R&D Projects: GA ČR GA101/09/1166 Institutional support: RVO:61388998 Keywords : free and forced vibrations * eigenmodes * bundle of blades Subject RIV: BI - Acoustics
Damping Properties of the Hair Bundle
Baumgart, Johannes; Kozlov, Andrei S.; Risler, Thomas; Hudspeth, A. James
2015-01-01
The viscous liquid surrounding a hair bundle dissipates energy and dampens oscillations, which poses a fundamental physical challenge to the high sensitivity and sharp frequency selectivity of hearing. To identify the mechanical forces at play, we constructed a detailed finite-element model of the hair bundle. Based on data from the hair bundle of the bullfrog's sacculus, this model treats the interaction of stereocilia both with the surrounding liquid and with the liquid in the narrow gaps b...
Static stress analysis of CANFLEX fuel bundles
International Nuclear Information System (INIS)
The static stress analysis of CANFLEX bundles is performed to evaluate the fuel structural integrity during the refuelling service. The structure analysis is carried out by predicting the drag force, stress and displacements of the fuel bundle. By the comparison of strength tests and analysis results, the displacement values are well agreed within 15%. The analysis shows that the CANFLEX fuel bundle keep its structural integrity. 24 figs., 6 tabs., 12 refs. (Author) .new
Statistical Constitutive Equation of Aramid Fiber Bundles
Institute of Scientific and Technical Information of China (English)
熊杰; 顾伯洪; 王善元
2003-01-01
Tensile impact tests of aramid (Twaron) fiber bundles were carried om under high strain rates with a wide range of 0. 01/s～1000/s by using MTS and bar-bar tensile impact apparatus. Based on the statistical constitutive model of fiber bundles, statistical constitutive equations of aramid fiber bundles are derived from statistical analysis of test data at different strain rates. Comparison between the theoretical predictions and experimental data indicates statistical constitutive equations fit well with the experimental data, and statistical constitutive equations of fiber bundles at different strain rates are valid.
Hydraulic characteristics of HANARO fuel bundles
Energy Technology Data Exchange (ETDEWEB)
Cho, S.; Chung, H. J.; Chun, S. Y.; Yang, S. K.; Chung, M. K. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)
1997-12-31
This paper presents the hydraulic characteristics measured by using LDV (Laser Doppler Velocimetry) in subchannels of HANARO, KAERI research reactor, fuel bundle. The fuel bundle consists of 18 axially finned rods with 3 spacer grids, which are arranged in cylindrical configuration. The effects of the spacer grids on the turbulent flow were investigated by the experimental results. Pressure drops for each component of the fuel bundle were measured, and the friction factors of fuel bundle and loss coefficients for the spacer grids were estimated from the measured pressure drops. Implications regarding the turbulent thermal mixing were discussed. Vibration test results measured by using laser vibrometer were presented. 9 refs., 12 figs. (Author)
Extension of holomorphic bundles to the disc (and Serre's Problem on Stein bundles)
Rosay, Jean-Pierre
2006-01-01
We show how to extend some holomorphic bundles with fifer C^2 and base an open set in C, to bundles on the Riemann Sphere, by an extremely simple technique. In particular, it applies to examples of non-Stein bundles constructed by Skoda and Demailly. It gives an example on C, with polynomial transition automorphisms.
Damping Properties of the Hair Bundle
Baumgart, Johannes; Kozlov, Andrei S.; Risler, Thomas; Hudspeth, A. J.
2011-11-01
The viscous liquid surrounding a hair bundle dissipates energy and dampens oscillations, which poses a fundamental physical challenge to the high sensitivity and sharp frequency selectivity of hearing. To identify the mechanical forces at play, we constructed a detailed finite-element model of the hair bundle. Based on data from the hair bundle of the bullfrog's sacculus, this model treats the interaction of stereocilia both with the surrounding liquid and with the liquid in the narrow gaps between the individual stereocilia. The investigation revealed that grouping stereocilia in a bundle dramatically reduces the total drag. During hair-bundle deflections, the tip links potentially induce drag by causing small but very dissipative relative motions between stereocilia; this effect is offset by the horizontal top connectors that restrain such relative movements at low frequencies. For higher frequencies the coupling liquid is sufficient to assure that the hair bundle moves as a unit with a low total drag. This work reveals the mechanical characteristics originating from hair-bundle morphology and shows quantitatively how a hair bundle is adapted for sensitive mechanotransduction.
Fingal, Diana
2009-01-01
Technology has changed for the past three decades, but the issues have not. Educators still face barriers to incorporating technology into their lessons. In the past, Dave Moursund, the first executive director of International Society for Technology in Education, wrote editorials predicting technology's impact on education. In this article, the…
Effect of bundle size on BWR fuel bundle critical power performance
International Nuclear Information System (INIS)
Effect of the bundle size on the BWR fuel bundle critical power performance was studied. For this purpose, critical power tests were conducted with both 6 x 6 (36 heater rods) and 12 x 12 (144 heater rods) size bundles in the GE ATLAS heat transfer test facility located in San Jose, California. All the bundle geometries such as rod diameter, rod pitch and rod space design are the same except size of flow channel. Two types of critical power tests were performed. One is the critical power test with uniform local peaking pattern for direct comparison of the small and large bundle critical power. Other is the critical power test for lattice positions in the bundle. In this test, power of a group of four rods (2 x 2 array) in a lattice region was peaked higher to probe the critical power of that lattice position in the bundle. In addition, the test data were compared to the COBRAG calculations. COBRAG is a detailed subchannel analysis code for BWR fuel bundle developed by GE Nuclear Energy. Based on these comparisons the subchannel model was refined to accurately predict the data obtained in this test program, thus validating the code capability of handling the effects of bundle size on bundle critical power for use in the study of the thermal hydraulic performance of the future advance BWR fuel bundle design. The author describes the experimental portion of the study program
Deformations of the generalised Picard bundle
International Nuclear Information System (INIS)
Let X be a nonsingular algebraic curve of genus g ≥ 3, and let Mξ denote the moduli space of stable vector bundles of rank n ≥ 2 and degree d with fixed determinant ξ over X such that n and d are coprime. We assume that if g = 3 then n ≥ 4 and if g = 4 then n ≥ 3, and suppose further that n0, d0 are integers such that n0 ≥ 1 and nd0 + n0d > nn0(2g - 2). Let E be a semistable vector bundle over X of rank n0 and degree d0. The generalised Picard bundle Wξ(E) is by definition the vector bundle over Mξ defined by the direct image pMξ *(Uξ x pX*E) where Uξ is a universal vector bundle over X x Mξ. We obtain an inversion formula allowing us to recover E from Wξ(E) and show that the space of infinitesimal deformations of Wξ(E) is isomorphic to H1(X, End(E)). This construction gives a locally complete family of vector bundles over Mξ parametrised by the moduli space M(n0,d0) of stable bundles of rank n0 and degree d0 over X. If (n0,d0) = 1 and Wξ(E) is stable for all E is an element of M(n0,d0), the construction determines an isomorphism from M(n0,d0) to a connected component M0 of a moduli space of stable sheaves over Mξ. This applies in particular when n0 = 1, in which case M0 is isomorphic to the Jacobian J of X as a polarised variety. The paper as a whole is a generalisation of results of Kempf and Mukai on Picard bundles over J, and is also related to a paper of Tyurin on the geometry of moduli of vector bundles. (author)
Geometry of quantum principal bundles, 1
Durdevic, M
1995-01-01
A theory of principal bundles possessing quantum structure groups and classical base manifolds is presented. Structural analysis of such quantum principal bundles is performed. A differential calculus is constructed, combining differential forms on the base manifold with an appropriate differential calculus on the structure quantum group. Relations between the calculus on the group and the calculus on the bundle are investigated. A concept of (pseudo)tensoriality is formulated. The formalism of connections is developed. In particular, operators of horizontal projection, covariant derivative and curvature are constructed and analyzed. Generalizations of the first structure equation and of the Bianchi identity are found. Illustrative examples are presented.
Weak equivalence classes of complex vector bundles
Hông-Vân Lê
2006-01-01
For any complex vector bundle Ek of rank k over a manifold Mm with Chern classes ci Î H2i(Mm, Z) and any non-negative integers l1, . . ., lk we show the existence of a positive number p(m, k) and the existence of a complex vector bundle Êk over Mm whose Chern classes are p(m, k) × li × ci Î H2i(Mm, Z). We also discuss a version of this statement for holomorphic vector bundles over projective algebraic manifolds.
Quantum Bundle Description of Quantum Projective Spaces
Ó Buachalla, Réamonn
2012-12-01
We realise Heckenberger and Kolb's canonical calculus on quantum projective ( N - 1)-space C q [ C p N-1] as the restriction of a distinguished quotient of the standard bicovariant calculus for the quantum special unitary group C q [ SU N ]. We introduce a calculus on the quantum sphere C q [ S 2 N-1] in the same way. With respect to these choices of calculi, we present C q [ C p N-1] as the base space of two different quantum principal bundles, one with total space C q [ SU N ], and the other with total space C q [ S 2 N-1]. We go on to give C q [ C p N-1] the structure of a quantum framed manifold. More specifically, we describe the module of one-forms of Heckenberger and Kolb's calculus as an associated vector bundle to the principal bundle with total space C q [ SU N ]. Finally, we construct strong connections for both bundles.
Evaluation on BDI of large diameter pin bundles by out-of-pile bundle compression test
International Nuclear Information System (INIS)
Bundle-duct interaction (BDI) in core fuel subassemblies in fast reactors (FRs) is a limiting factor for fuel burnup. Since the large diameter fuel pin is generally believed to be a measure to improve FR fuel performance, the out-of-pile bundle compression test with large diameter pins (φ8.5mm and (φ 10.4mm) was performed to evaluate BDI in these bundles. In the compression test, bundle cross-sectional images (CT images) under BDI condition were obtained by using the X-ray computer tomography. In the main study, the CT images were numerically analyzed to evaluate deformation of the large diameter pin bundle due to BDI. The CT image analysis results revealed that pin-to-duct contact did not occur when the flat-to-flat bundle compression level reached one wire diameter (BDI level of 1dw), which indicates that BDI in large diameter pin bundles was mitigated similarly to the currently used small diameter pin bundles. In addition, the mitigation mechanism for BDI, which delays initiation of pin-to-duct contact, was investigated by using the computer code analysis. The code analysis results showed that cladding oval-distortion acted as a major mitigation mechanism for BDI as in the case of small pin diameter bundles. (author)
Self-mapping degrees of torus bundles and torus semi-bundles
Sun, Hongbin; Wang, Shicheng; Wu, Jianchun
2010-01-01
Each closed oriented 3-manifold $M$ is naturally associated with a set of integers $D(M)$, the degrees of all self-maps on $M$. $D(M)$ is determined for each torus bundle and torus semi-bundle $M$. The structure of torus semi-bundle is studied in detail. The paper is a part of a project to determine $D(M)$ for all 3-manifolds in Thurston's picture.
Institute of Scientific and Technical Information of China (English)
YU Wei-dong; YAN Hao-jing; Ron Postle; Yang Shouren
2002-01-01
Due to the effects of samples and testing conditions on fibre-bundle tensile behaviour, it is necessary to investigate the relationships between experimental factors and tensile properties for the fibre-bumdle tensile tester (TENSOR). The effects of bundle sample preparation, fibre bundle mass and fibre alignment have been tested. The experimental results indicated that (1) the low damage in combing and no free-end fibres in the cut bundle are most important for the sample preparation; (2) the reasonable bundle mass is 400- 700tex, but the tensile properties measured should bemodified with the bundle mass because a small amount of bundle mass causes the scatter results, while the larger is the bundle mass, the more difficult to comb fibres parallel and to clamp fibre evenly; and (3) the fibre irregular arrangement forms a slack bundle resulting in interaction between fibres, which will affect the reproducibility and accuracy of the tensile testing.
Mechanism of Actin Filament Bundling by Fascin
Energy Technology Data Exchange (ETDEWEB)
Jansen, Silvia; Collins, Agnieszka; Yang, Changsong; Rebowski, Grzegorz; Svitkina, Tatyana; Dominguez, Roberto (UPENN); (UPENN-MED)
2013-03-07
Fascin is the main actin filament bundling protein in filopodia. Because of the important role filopodia play in cell migration, fascin is emerging as a major target for cancer drug discovery. However, an understanding of the mechanism of bundle formation by fascin is critically lacking. Fascin consists of four {beta}-trefoil domains. Here, we show that fascin contains two major actin-binding sites, coinciding with regions of high sequence conservation in {beta}-trefoil domains 1 and 3. The site in {beta}-trefoil-1 is located near the binding site of the fascin inhibitor macroketone and comprises residue Ser-39, whose phosphorylation by protein kinase C down-regulates actin bundling and formation of filopodia. The site in {beta}-trefoil-3 is related by pseudo-2-fold symmetry to that in {beta}-trefoil-1. The two sites are {approx}5 nm apart, resulting in a distance between actin filaments in the bundle of {approx}8.1 nm. Residue mutations in both sites disrupt bundle formation in vitro as assessed by co-sedimentation with actin and electron microscopy and severely impair formation of filopodia in cells as determined by rescue experiments in fascin-depleted cells. Mutations of other areas of the fascin surface also affect actin bundling and formation of filopodia albeit to a lesser extent, suggesting that, in addition to the two major actin-binding sites, fascin makes secondary contacts with other filaments in the bundle. In a high resolution crystal structure of fascin, molecules of glycerol and polyethylene glycol are bound in pockets located within the two major actin-binding sites. These molecules could guide the rational design of new anticancer fascin inhibitors.
Johan Kommers
2014-01-01
The founder of the Keswick Convention (KC) once was asked to put in a sentence that has brought such a joy into his life and made the name of Keswick fragrant over the whole world. The answer was in the words of the Psalm 16:8, ‘I have set the Lord always before me’. Keswick theology, emphasising sanctification, arose within the concept of the holiness tradition in America with the higher Christian life movement in England during the second part of the 19th century. The merging of several the...
International Nuclear Information System (INIS)
PNC has been developing a computer code 'BAMBOO' to analyze the wire spaced FBR fuel pin bundle deformation under the BDI (Bundle Duct Interaction) condition by means of the three dimensional F.E.M. This code analyzes fuel pins' bowing and oval deformations which are dominant deformation behaviors of the fuel pin bundle under the BDI condition. In this study the 'BAMBOO' code is validated on the out-of-pile compression test of the FBR bundle (compression test) by comparing the results of the code analysis with the compression test results, and the highly irradiated (≥2.1x1027 n/m2, E > 0.1 MeV) bundle deformation behaviors are investigated from the viewpoint of the similarity to those in the compression test based on the analytical results of the code. (1) The calculated pin-to-duct minimum clearances as a function of the BDI levels in the compression test analysis agree with the experimental values evaluated from the CT image analysis of the bundle cross-section in the compression test within ±0.2 mm. And the calculated values of the fuel pins' oval deformations agree with the experimental values based on the pin diameter measurements done after the compression test within ±0.05 mm. (2) By comparing the irradiation induced bundle deformation with the bundle deformation in the compression test based on the code analysis, it is confirmed that the changes of the pin-to-duct minimum clearances with the BDI levels show equivalent trends between the both bundle deformations. And in this code analysis of the irradiation induced bundle deformation, contact loads between the fuel pins and the pacer wires are extremely small (below 10 kgf) even at about 3 dw of the BDI level compared to those in the compression test analysis. (J.P.N.)
A bundle of sticks in my garden
Farran, Sue
2012-01-01
The English law of property is often described as a ‘bundle of sticks’ in which each ‘stick’ represents a particular right. Gardens challenge these rights and wreak havoc on the ‘bundle of sticks’. This paper looks at the twenty-first century manifestations of community engagement with ground and explores how ‘gardening’ is undermining concepts of ownership, possession and management of land and how the fence between what is private and what is public is being encroached and challenged by com...
Characteristic classes of quantum principal bundles
Durdevic, M
1995-01-01
A noncommutative-geometric generalization of classical Weil theory of characteristic classes is presented, in the conceptual framework of quantum principal bundles. A particular care is given to the case when the bundle does not admit regular connections. A cohomological description of the domain of the Weil homomorphism is given. Relations between universal characteristic classes for the regular and the general case are analyzed. In analogy with classical geometry, a natural spectral sequence is introduced and investigated. The appropriate counterpart of the Chern character is constructed, for structures admitting regular connections. Illustrative examples and constructions are presented.
Josef Steindl: An Economist of His Times
Directory of Open Access Journals (Sweden)
Nina Shapiro
2012-09-01
Full Text Available This paper discusses the life and work of Josef Steindl. It examines the development of his thought from his early writings on firm size and industrial concentration to his late work on the post-war problems of capitalist economies. Special attention is given to his seminal work on the Great Depression: Maturity and Stagnation in American Capitalism (1952. His work, which covered all the critical economic developments of the 20th century, greatly illuminated the problems of his times, and is as relevant to the problems of our own as it was to his.
Directory of Open Access Journals (Sweden)
Johan Kommers
2014-03-01
Full Text Available The founder of the Keswick Convention (KC once was asked to put in a sentence that has brought such a joy into his life and made the name of Keswick fragrant over the whole world. The answer was in the words of the Psalm 16:8, ‘I have set the Lord always before me’. Keswick theology, emphasising sanctification, arose within the concept of the holiness tradition in America with the higher Christian life movement in England during the second part of the 19th century. The merging of several theological traditions formed a way of expressing oneself and a way of life, which was determined as typical ‘Keswickian’. It also found expression in other theological (conservative movements, in new founded institutions and gave a boost to missionary enterprise. The language and the teaching of Keswick until today clarify the pattern of evangelical piety of the 20th century.
Capacity efficiency of recovery request bundling
DEFF Research Database (Denmark)
Ruepp, Sarah Renée; Dittmann, Lars; Berger, Michael Stübert; Stidsen, Thomas Riis; Lagakos, Stephen; Perlovsky, Leonid; Jha, Manoi; Covaci, Brindusa; Zaharim, Azarni; Mastorakis, Nikos
2010-01-01
This paper presents a comparison of recovery methods in terms of capacity efficiency. In particular, a method where recovery requests are bundled towards the destination (Shortcut Span Protection) is evaluated against traditional recovery methods. Our simulation results show that Shortcut Span Pr...... Protection uses more capacity than the unbundled related methods, but this is compensated by easier control and management of the recovery actions....
Optimization of a bundle divertor for FED
International Nuclear Information System (INIS)
Optimal double-T bundle divertor configurations have been obtained for the Fusion Engineering Device (FED). On-axis ripple is minimized, while satisfying a series of engineering constraints. The ensuing non-linear optimization problem is solved via a sequence of quadratic programming subproblems, using the VMCON algorithm. The resulting divertor designs are substantially improved over previous configurations
Capacity efficiency of recovery request bundling
DEFF Research Database (Denmark)
Ruepp, Sarah Renée; Dittmann, Lars; Berger, Michael Stübert; Stidsen, Thomas Riis; Lagakos, Stephen; Perlovsky, Leonid; Jha, Manoi; Covaci, Brindusa; Zaharim, Azarni; Mastorakis, Nikos
2010-01-01
This paper presents a comparison of recovery methods in terms of capacity efficiency. In particular, a method where recovery requests are bundled towards the destination (Shortcut Span Protection) is evaluated against traditional recovery methods. Our simulation results show that Shortcut Span...
Impact of bundle deformation on CHF: ASSERT-PV assessment of extended burnup Bruce B bundle G85159W
International Nuclear Information System (INIS)
This paper presents a subchannel thermalhydraulic analysis of the effect on critical heat flux (CHF) of bundle deformation such as element bow and diametral creep. The bundle geometry is based on the post-irradiation examination (PIE) data of a single bundle from the Bruce B Nuclear Generating Station, Bruce B bundle G85159W, which was irradiated for more than two years in the core during reactor commissioning. The subchannel code ASSERT-PV IST is used to assess changes in CHF and dryout power due to bundle deformation, compared to the reference, undeformed bundle. (author)
Compactifications of reductive groups as moduli stacks of bundles
DEFF Research Database (Denmark)
Martens, Johan; Thaddeus, Michael
Let G be a reductive group. We introduce the moduli problem of "bundle chains" parametrizing framed principal G-bundles on chains of lines. Any fan supported in a Weyl chamber determines a stability condition on bundle chains. Its moduli stack provides an equivariant toroidal compactification of ...
Stability of Picard Bundle Over Moduli Space of Stable Vector Bundles of Rank Two Over a Curve
Indian Academy of Sciences (India)
Indranil Biswas; Tomás L Gómez
2001-08-01
Answering a question of [BV] it is proved that the Picard bundle on the moduli space of stable vector bundles of rank two, on a Riemann surface of genus at least three, with fixed determinant of odd degree is stable.
In-pile test of Qinshan PWR fuel bundle
International Nuclear Information System (INIS)
In-pile test of Qinshan Nuclear Power Plant PWR fuel bundle has been conducted in HWRR HTHP Test loop at CIAE. The test fuel bundle was irradiated to an average burnup of 25000 Mwd/tU. The authors describe the structure of (3 x 3-2) test fuel bundle, structure of irradiation rig, fuel fabrication, irradiation conditions, power and fuel burnup. Some comments on the in-pile performance for fuel bundle, fuel rod and irradiation rig were made
Existence of vector bundles and global resolutions for singular surfaces
Vezzosi, G; S. SCHROER
2002-01-01
Abstract- We prove two results about vector bundles on singular algebraic surfaces. First, on proper surfaces there are vector bundles of rank two with arbitrarily large second Chern number and fixed determinant. Second, on separated normal surfaces any coherent sheaf is the quotient of a vector bundle. As a consequence, for such surfaces the Quillen K-theory of vector bundles coincides with the Waldhausen K-theory of perfect complexes. Examples show that, on non-separated schemes, usually...
Geometry of torus bundles in integrable Hamiltonian systems
Lukina, Olga
2008-01-01
Thesis is concerned with global properties of Lagrangian bundles, i.e. symplectic n-torus bundles, as these occur in integrable Hamiltonian systems. It treats obstructions to triviality and concerns with classification of such bundles, as well as with manifestations of global invariants in real-worl
Laser cutting for dismantling of PHWR fuel bundles
International Nuclear Information System (INIS)
Detailed investigation was carried out on laser cutting of zircaloy-2 PHWR fuel pin bundles. Initially, trials were done to standardize ten parameters for cutting of tie plates to which individual fuel pins are welded in a bundle. Using these parameters, the tie plates were cut into several pieces so that each fuel pin is individually separated out from the bundle. (author)
Energy Technology Data Exchange (ETDEWEB)
Kaipainen, H.; Seppaenen, V.; Rinne, S.
1996-12-31
The conditions on which the bundling of the harvesting residues from spruce regeneration fellings would become profitable were studied. The calculations showed that one of the most important features was sufficient compaction of the bundle, so that the portion of the wood in the unit volume of the bundle has to be more than 40 %. The tests showed that the timber grab loader of farm tractor was insufficient for production of dense bundles. The feeding and compression device of the prototype bundler was constructed in the research and with this device the required density was obtained.The rate of compaction of the dry spruce felling residues was about 40 % and that of the fresh residues was more than 50 %. The comparison between the bundles showed that the calorific value of the fresh bundle per unit volume was nearly 30 % higher than that of the dry bundle. This means that the treatment of the bundles should be done of fresh felling residues. Drying of the bundles succeeded well, and the crushing and chipping tests showed that the processing of the bundles at the plant is possible. The treatability of the bundles was also excellent. By using the prototype, developed in the research, it was possible to produce a bundle of the fresh spruce harvesting residues, the diameter of which was about 50 cm and the length about 3 m, and the rate of compaction over 50 %. By these values the reduction target of the costs is obtainable
Productivity and costs of slash bundling in Nordic conditions
Energy Technology Data Exchange (ETDEWEB)
Kaerhae, K.; Vartiamaeki, T. [Metsaeteho Oy, P.O. Box 101, FI-00171 Helsinki (Finland)
2006-12-15
The number of slash bundlers and the volume of slash bundling have been rapidly increasing during the last few years in Finland. However, no comprehensive time or follow-up studies have been carried out on slash bundling technology in Finland or in any other country. Metsateho Oy carried out studies on the productivity and costs of slash bundling in different Nordic recovering conditions. The study methods included both time and follow-up studies. Data were collected during the summer and winter period primarily in Norway spruce (Picea abies L. Karst.) dominated clear cutting sites. The bundling techniques performed by different types of bundler (Fiberpac 370, Timberjack 1490D, Pika RS 2000, Valmet WoodPac) were studied. The average productivity of slash bundling was 18.1 bundles per operating (E{sub 15}, including delays shorter than 15min) hour with the Timberjack 1490D and Fiberpac 370 bundlers in the follow-up study. The operator of the slash bundler had the greatest effect on the productivity of bundling. The prerequisite for increased bundling volumes is a reduction in the costs of the most expensive sub-stage of the bundling supply chain, i.e. bundling itself. This requires improved recovery conditions at bundling sites, increased bundling productivity, larger sized bundles, and the execution of bundling operations in two work shifts using an efficient bundler and effective operator working methods. Implementation of these development measures will bring the bundling supply chain up to a speed that makes it the most competitive supply chain for forest chips in terms of total supply costs for long-distance transportation distances of more than 60km. (author)
A fibre bundle formulation of quantum geometry
International Nuclear Information System (INIS)
Quantum geometries whose points are stochastic and serve as seats for quantum space-time excitons are formulated as fibre bundles over base spaces of mean values with a Minkowski or general relativistic structure. The fibres contain the proper wave functions of all exciton states in a given model. The notion of covariance and propagation in quantum space-times constituting such fibre bundles is investigated. Maxwell and Yang-Mills gauge degrees of freedom are introduced by appropriately enlarging the structure group, which in all cases contains phase-space representations of the Poincare group corresponding to the exciton wave function sample space specific to a given model. It is shown that these formulations give rise in a natural manner to certain realizations of the relativistic canonical commutation relations in terms of covariant derivatives involving internal as well as external degrees of freedom of space-time excitons
Effective freeness of adjoint line bundles
Heier, Gordon
2001-01-01
In this note we establish a new Fujita-type effective bound for the base point freeness of adjoint line bundles on a compact complex projective manifold of complex dimension $n$. The bound we obtain (approximately) differs from the linear bound conjectured by Fujita only by a factor of the cube root of $n$. As an application, a new effective statement for pluricanonical embeddings is derived.
Reactor application of an improved bundle divertor
International Nuclear Information System (INIS)
A Bundle Divertor was chosen as the impurity control and plasma exhaust system for the beam driven Demonstration Tokamak Hybrid Reactor - DTHR. In the context of a preconceptual design study of the reactor and associated facility a bundle divertor concept was developed and integrated into the reactor system. The overall system was found feasible and scalable for reactors with intermediate torodial field strengths on axis. The important design characteristics are: the overall average current density of the divertor coils is 0.73 kA for each tesla of toroidal field on axis; the divertor windings are made from super-conducting cables supported by steel structures and are designed to be maintainable; the particle collection assembly and auxiliary cryosorption vacuum pump are dual systems designed such that they can be reactivated alterntively to allow for continuous reactor operation; and the power requirement for energizing and operating the divertor is about 5 MW
Effectiveness of Hair Bundle Motility as the Cochlear Amplifier
Sul, Bora; Iwasa, Kuni H.
2009-01-01
The effectiveness of hair bundle motility in mammalian and avian ears is studied by examining energy balance for a small sinusoidal displacement of the hair bundle. The condition that the energy generated by a hair bundle must be greater than energy loss due to the shear in the subtectorial gap per hair bundle leads to a limiting frequency that can be supported by hair-bundle motility. Limiting frequencies are obtained for two motile mechanisms for fast adaptation, the channel re-closure mode...
Andrei Siniavskii. A hero of his time?
Markesinis, E. F.
2010-01-01
This thesis is an artistic biography of Andrei Siniavskii (1925-1997) as a writer in and of his time, showing how this subtle and complex author found his way in a society polarised into heroes and villains, patriots and traitors; how he progresses from identification with the value system and ideology of his time to reaction against it, his dissidence expressed in literary terms. Beyond this, I hope to show how he moves to a new conception of the writer in the fusion of his...
Compression of a bundle of light rays.
Marcuse, D
1971-03-01
The performance of ray compression devices is discussed on the basis of a phase space treatment using Liouville's theorem. It is concluded that the area in phase space of the input bundle of rays is determined solely by the required compression ratio and possible limitations on the maximum ray angle at the output of the device. The efficiency of tapers and lenses as ray compressors is approximately equal. For linear tapers and lenses the input angle of the useful rays must not exceed the compression ratio. The performance of linear tapers and lenses is compared to a particular ray compressor using a graded refractive index distribution. PMID:20094478
A man of his country and his time: Jewish influences on Lev Semionovich Vygotsky's world view.
Kotik-Friedgut, Bella; Friedgut, Theodore H
2008-02-01
Lev Semionovich Vygotsky created the cultural-historical school of psychology, yet all too few of those writing about his work take into account the family, education, and cultural tradition from which he came. The authors contend that the Jewish nature of these elements was of some importance in forming his personality and his consciousness. The 1st part of the article traces his early upbringing, describes the Jewishness of his environment, notes 3 instances in which his "otherness" was imprinted on his consciousness, and points to the sources of his determination to forge a harmonious synthesis with his environment. The 2nd part examines his writings, both earlier journalistic and mature psychological, and points to evidence of the influence of his Jewish upbringing and environment on his work. PMID:19048956
Systematic Bundle Adjustment of HRSC Image Data
Bostelmann, J.; Schmidt, R.; Heipke, C.
2012-07-01
The European Mars Express mission was launched in June 2003 and sent into orbit around Mars. On board the orbiter is the German High Resolution Stereo Camera (HRSC). This multi-line sensor images the Martian surface with a resolution of up to 12m per pixel in three dimensions and provides RGB and infra-red color information. The usage of the stereoscopic image information for the improvement of the observed position and attitude information via bundle adjustment is important to derive high quality 3D surface models, color orthoimages and other data products. In many cases overlapping image strips of different orbits can be used to form photogrammetric blocks, thus allowing the simultaneous adjustment of the exterior orientation data. This reduces not only local, but also regional inconsistencies in the data. With the growing number of HRSC image strips in this ongoing mission, the size and complexity of potential blocks is increasing. Therefore, a workflow has been built up for the systematic improvement of the exterior orientation using single orbit strips and regional blocks. For a successful bundle adjustment of blocks using multiple image strips a sufficient number of tie points in the overlapping area is needed. The number of tie points depends mainly on the geometric and radiometric quality of the images. This is considered by detailed analysis of the tie point accuracy and distribution. The combination of methods for image pre-processing, tie point matching, bundle adjustment and evaluation of the results in an automated workflow allows for all HRSC images a global assessment of the quality and a systematic selection of data for larger blocks.
Hydrodynamic behavior of a bare rod bundle
International Nuclear Information System (INIS)
The temperature distribution within the rod bundle of a nuclear reactor is of major importance in nuclear reactor design. However temperature information presupposes knowledge of the hydrodynamic behavior of the coolant which is the most difficult part of the problem due to complexity of the turbulence phenomena. In the present work a 2-equation turbulence model--a strong candidate for analyzing actual three dimensional turbulent flows--has been used to predict fully developed flow of infinite bare rod bundle of various aspect ratios (P/D). The model has been modified to take into account anisotropic effects of eddy viscosity. Secondary flow calculations have been also performed although the model seems to be too rough to predict the secondary flow correctly. Heat transfer calculations have been performed to confirm the importance of anisotropic viscosity in temperature predictions. All numerical calculations for flow and heat have been performed by two computer codes based on the TEACH code. Experimental measurements of the distribution of axial velocity, turbulent axial velocity, turbulent kinetic energy and radial Reynolds stresses were performed in the developing and fully developed regions. A 2-channel Laser Doppler Anemometer working on the Reference mode with forward scattering was used to perform the measurements in a simulated interior subchannel of a triangular rod array with P/D = 1.124. Comparisons between the analytical results and the results of this experiment as well as other experimental data in rod bundle array available in literature are presented. The predictions are in good agreement with the results for the high Reynolds numbers
Adsorption of Argon on Carbon nanotube bundles and its influence on the bundle lattice parameter
International Nuclear Information System (INIS)
We report experimental studies of the adsorption characteristics and structure of both Ar36 and Ar40 on single-wall carbon nanotube bundles. The structural studies make use of the large difference in coherent neutron scattering cross section for the two Ar isotopes to explore the influence of the adsorbate on the nanotube lattice parameter. We observe no dilation of the nanotube lattice with Ar40, and explain the apparent expansion of this lattice upon Ar36 adsorption by the location of the adsorbed Ar atoms on the outer bundle surface
Differential geometry of complex vector bundles
Kobayashi, Shoshichi
2014-01-01
Holomorphic vector bundles have become objects of interest not only to algebraic and differential geometers and complex analysts but also to low dimensional topologists and mathematical physicists working on gauge theory. This book, which grew out of the author's lectures and seminars in Berkeley and Japan, is written for researchers and graduate students in these various fields of mathematics. Originally published in 1987. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeto
Numerical simulations of square arrayed rod bundles
International Nuclear Information System (INIS)
Highlights: ► CFD simulations with square arrayed rod bundles. ► Mesh dependency and turbulence model study by comparison with experiments. ► Gibson and Launder Reynolds stress model shows good agreement with experiments. ► Effect of pitch to diameter ratio and Reynolds number is correctly captured. - Abstract: Computational fluid dynamics (CFD) simulations were performed with square arrayed rod bundles featuring pitch to diameter (P/D) ratio of 1.194 and 1.326 in order to find an optimal mesh and turbulence model for simulations with more complex geometries in the future. With the tighter lattice a mesh sensitivity and turbulence model study were accomplished and the post processed turbulence quantities, velocity field and wall shear stress were compared with experimental data ( Developed single phase turbulent flow through a square-pitch rod cluster. Nuclear Engineering and Design 60, 365–379.). The comparisons show that Reynolds-Averaged Navier–Stokes method with the Reynolds stress model of Gibson and Launder in conjunction with an appropriate mesh can provide reasonable agreement with the experiment for this lattice. For pure bundle simulations the body fitted structured meshes are suggested, since slightly better agreement can be captured considering all quantities with the same number of cells. Based on the drawn conclusions the procession was repeated for P/D = 1.326, where, due to lack of experiment, just the correct tendencies of the turbulence quantities and velocity field were established. The results show Reynolds number independency correctly and the increase of P/D issues in more similar flow to axisymmetric pipe flow.
Bohr's Creation of his Quantum Atom
Heilbron, John
2013-04-01
Fresh letters throw new light on the content and state of Bohr's mind before and during his creation of the quantum atom. His mental furniture then included the atomic models of the English school, the quantum puzzles of Continental theorists, and the results of his own studies of the electron theory of metals. It also included the poetry of Goethe, plays of Ibsen and Shakespeare, novels of Dickens, and rhapsodies of Kierkegaard and Carlyle. The mind that held these diverse ingredients together oscillated between enthusiasm and dejection during the year in which Bohr took up the problem of atomic structure. He spent most of that year in England, which separated him for extended periods from his close-knit family and friends. Correspondence with his fianc'ee, Margrethe Nørlund, soon to be published, reports his ups and downs as he adjusted to J.J. Thomson, Ernest Rutherford, the English language, and the uneven course of his work. In helping to smooth out his moods, Margrethe played an important and perhaps an enabling role in his creative process.
Amplitude death of coupled hair bundles with stochastic channel noise
Kim, Kyung-Joong
2014-01-01
Hair cells conduct auditory transduction in vertebrates. In lower vertebrates such as frogs and turtles, due to the active mechanism in hair cells, hair bundles(stereocilia) can be spontaneously oscillating or quiescent. Recently, the amplitude death phenomenon has been proposed [K.-H. Ahn, J. R. Soc. Interface, {\\bf 10}, 20130525 (2013)] as a mechanism for auditory transduction in frog hair-cell bundles, where sudden cessation of the oscillations arises due to the coupling between non-identical hair bundles. The gating of the ion channel is intrinsically stochastic due to the stochastic nature of the configuration change of the channel. The strength of the noise due to the channel gating can be comparable to the thermal Brownian noise of hair bundles. Thus, we perform stochastic simulations of the elastically coupled hair bundles. In spite of stray noisy fluctuations due to its stochastic dynamics, our simulation shows the transition from collective oscillation to amplitude death as inter-bundle coupling str...
A Tannakian approach to dimensional reduction of principal bundles
Álvarez-Cónsul, Luis; García-Prada, Oscar
2016-01-01
Let $P$ be a parabolic subgroup of a connected simply connected complex semisimple Lie group $G$. Given a compact K\\"ahler manifold $X$, the dimensional reduction of $G$-equivariant holomorphic vector bundles over $X\\times G/P$ was carried out by the first and third authors. This raises the question of dimensional reduction of holomorphic principal bundles over $X\\times G/P$. The method used for equivariant vector bundles does not generalize to principal bundles. In this paper, we adapt to equivariant principal bundles the Tannakian approach of Nori, to describe the dimensional reduction of $G$-equivariant principal bundles over $X\\times G/P$, and to establish a Hitchin--Kobayashi type correspondence. In order to be able to apply the Tannakian theory, we need to assume that $X$ is a complex projective manifold.
Contacting single bundles of carbon nanotubes with alternating electric fields
Krupke, R.; Hennrich, F.; Weber, H. B.; Beckmann, D.; Hampe, O.; Malik, S.; Kappes, M. M.; Löhneysen, H. v.
2002-01-01
Single bundles of carbon nanotubes have been selectively deposited from suspensions onto sub-micron electrodes with alternating electric fields. We explore the resulting contacts using several solvents and delineate the differences between Au and Ag as electrode materials. Alignment of the bundles between electrodes occurs at frequencies above 1 kHz. Control over the number of trapped bundles is achieved by choosing an electrode material which interacts strongly with the chemical functional g...
Robust Mapping of Incoherent Fiber-Optic Bundles
Roberts, Harry E.; Deason, Brent E.; DePlachett, Charles P.; Pilgrim, Robert A.; Sanford, Harold S.
2007-01-01
A method and apparatus for mapping between the positions of fibers at opposite ends of incoherent fiber-optic bundles have been invented to enable the use of such bundles to transmit images in visible or infrared light. The method is robust in the sense that it provides useful mapping even for a bundle that contains thousands of narrow, irregularly packed fibers, some of which may be defective. In a coherent fiber-optic bundle, the input and output ends of each fiber lie at identical positions in the input and output planes; therefore, the bundle can be used to transmit images without further modification. Unfortunately, the fabrication of coherent fiber-optic bundles is too labor-intensive and expensive for many applications. An incoherent fiber-optic bundle can be fabricated more easily and at lower cost, but it produces a scrambled image because the position of the end of each fiber in the input plane is generally different from the end of the same fiber in the output plane. However, the image transmitted by an incoherent fiber-optic bundle can be unscrambled (or, from a different perspective, decoded) by digital processing of the output image if the mapping between the input and output fiber-end positions is known. Thus, the present invention enables the use of relatively inexpensive fiber-optic bundles to transmit images.
Enthalpy and void distributions in subchannels of PHWR fuel bundles
Energy Technology Data Exchange (ETDEWEB)
Park, J. W.; Choi, H.; Rhee, B. W. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)
1998-12-31
Two different types of the CANDU fuel bundles have been modeled for the ASSERT-IV code subchannel analysis. From calculated values of mixture enthalpy and void fraction distribution in the fuel bundles, it is found that net buoyancy effect is pronounced in the central region of the DUPIC fuel bundle when compared with the standard CANDU fuel bundle. It is also found that the central region of the DUPIC fuel bundle can be cooled more efficiently than that of the standard fuel bundle. From the calculated mixture enthalpy distribution at the exit of the fuel channel, it is found that the mixture enthalpy and void fraction can be highest in the peripheral region of the DUPIC fuel bundle. On the other hand, the enthalpy and the void fraction were found to be highest in the central region of the standard CANDU fuel bundle at the exit of the fuel channel. This study shows that the subchannel analysis is very useful in assessing thermal behavior of the fuel bundle that could be used in CANDU reactors. 10 refs., 4 figs., 2 tabs. (Author)
Steady-flow characteristics of bundle fluid in drawing
Energy Technology Data Exchange (ETDEWEB)
Huh, You; Kim, Jong Seong [Kyunghee University, Suwon (Korea, Republic of)
2006-07-15
Drawing is a mechanical operation attenuating material thickness to an appropriate level for the next processing or end usage. When the input material has a form of bundle or bundles made of very thin and long shaped wires or fibers, this attenuation operation is called 'bundle drawing' or 'drafting'. Bundle drawing is being used widely in manufacturing micro sized wires or staple yarns. However, the bundle processed by this operation has more or less defects in the evenness of linear density. Such irregularities cause many problems not only for the product quality but also for the efficiency of the next successive processes. In this research a mathematical model for the dynamic behavior of the bundle fluid is to be set up on the basis of general physical laws containing physical variables, i.e. linear density and velocity as the dynamic state variables of the bundle fluid. The governing equations resulting from the modeling show that they appear in a slightly different form from what they do in a continuum fluid. Then, the governing equations system is simplified in a steady state and the bundle dynamics is simulated, showing that the shape of the velocity profiles depends on two model parameters. Experiments confirm that the model parameters are to be well adjusted to show a coincidence with the theoretical analysis. The higher the drawing ratio and drawing speed are, the more sensitive becomes the bundle flow to exogenous disturbances.
On the Classification of Complex Vector Bundles of Stable Rank
Indian Academy of Sciences (India)
Constantin Bǎnicǎ; Mihai Putinar
2006-08-01
One describes, using a detailed analysis of Atiyah–Hirzebruch spectral sequence, the tuples of cohomology classes on a compact, complex manifold, corresponding to the Chern classes of a complex vector bundle of stable rank. This classification becomes more effective on generalized flag manifolds, where the Lie algebra formalism and concrete integrability conditions describe in constructive terms the Chern classes of a vector bundle.
Victor Henri: 111 years of his equation.
Cornish-Bowden, Athel; Mazat, Jean-Pierre; Nicolas, Serge
2014-12-01
Victor Henri's great contribution to the understanding of enzyme kinetics and mechanism is not always given the credit that it deserves. In addition, his earlier work in experimental psychology is totally unknown to biochemists, and his later work in spectroscopy and photobiology almost equally so. Applying great rigour to his analysis he succeeded in obtaining a model of enzyme action that explained all of the observations available to him, and he showed why the considerable amount of work done in the preceding decade had not led to understanding. His view was that only physical chemistry could explain the behaviour of enzymes, and that models should be judged in accordance with their capacity not only to explain previously known facts but also to predict new observations against which they could be tested. The kinetic equation usually attributed to Michaelis and Menten was in reality due to him. His thesis of 1903 is now available in English. PMID:25252213
Development of nuclear fuel. Development of CANDU advanced fuel bundle
International Nuclear Information System (INIS)
In order to develop CANDU advanced fuel, the agreement of the joint research between KAERI and AECL was made on February 19, 1991. AECL conceptual design of CANFLEX bundle for Bruce reactors was analyzed and then the reference design and design drawing of the advanced fuel bundle with natural uranium fuel for CANDU-6 reactor were completed. The CANFLEX fuel cladding was preliminarily investigated. The fabricability of the advanced fuel bundle was investigated. The design and purchase of the machinery tools for the bundle fabrication for hydraulic scoping tests were performed. As a result of CANFLEX tube examination, the tubes were found to be meet the criteria proposed in the technical specification. The dummy bundles for hydraulic scoping tests have been fabricated by using the process and tools, where the process parameters and tools have been newly established. (Author)
Subanalytic Bundles and Tubular Neighbourhoods of Zero-Loci
Indian Academy of Sciences (India)
Vishwambhar Pati
2003-08-01
We introduce the natural and fairly general notion of a subanalytic bundle (with a finite dimensional vector space of sections) on a subanalytic subset of a real analytic manifold , and prove that when is compact, there is a Baire subset of sections in whose zero-loci in have tubular neighbourhoods, homeomorphic to the restriction of the given bundle to these zero-loci.
Geometries and applications of active fiber bundles
Giglmayr, Josef
2001-10-01
Active fiber bundles (FBs) are aimed to model photonic switching and processing in 3-D without the restrictions of the photonic technology. The 2-D photonic architectures are assumed to be implemented by networks of directional couplers (DCs) and Mach-Zehnder interferometers (MZIs), respectively. For the implementation several crucial problems are expected: (1) proper operation of the spatial couplers/switches (nonblocking interconnections) and (2) coupling in the interstage interconnection section mainly caused by parallel and crossing fibers/waveguides (WGs). For the design of proper operating switches (refinement of couplers) the application of decoupling concepts of modern control theory is proposed. The final goal is to translate the refined couplers into integrated photonic architectures rather than into additional lightwave circuits (LWCs) which simply would increase the coupling. The decoupling concepts are reviewed. The paper is an attempt to prepare for applying well-known system engineering concepts to the upcoming technology of photonics.
The behaviour of Phenix fuel pin bundle under irradiation
International Nuclear Information System (INIS)
An entire Phenix sub-assembly has been mounted and sectioned after irradiation. The examination of cross-sections revealed the effects of mechanical interaction in the bundle (ovalisations and contacts between clads). According to analysis of the sodium channels, cooling of the pin bundle remained uniform. (author)
Extendability of parallel sections in vector bundles
Kirschner, Tim
2016-01-01
I address the following question: Given a differentiable manifold M, what are the open subsets U of M such that, for all vector bundles E over M and all linear connections ∇ on E, any ∇-parallel section in E defined on U extends to a ∇-parallel section in E defined on M? For simply connected manifolds M (among others) I describe the entirety of all such sets U which are, in addition, the complement of a C1 submanifold, boundary allowed, of M. This delivers a partial positive answer to a problem posed by Antonio J. Di Scala and Gianni Manno (2014). Furthermore, in case M is an open submanifold of Rn, n ≥ 2, I prove that the complement of U in M, not required to be a submanifold now, can have arbitrarily large n-dimensional Lebesgue measure.
Introduction to the theory of fiber bundles and connections I
International Nuclear Information System (INIS)
In lectures 1 and 2 we discuss basic concepts of topology and differential geometry: definition of a topological space and of Hausdorff, compact, connected and paracompact spaces; topological groups and actions of groups on spaces; differentiable manifolds, tangent vectors and 1 forms; partitions of unity and Lie groups. In lecture 3 we present the concept of a fiber bundle and discuss vector bundles and principal bundles. The concept of a connection on a smooth vector bundle is defined in lecture 4, together with the associated concepts of curvature and parallel transport; as an illustration we present the Levi-Civita connection on a Riemannian manifold. Finally, in lecture 5 we define connections on principal bundles and present examples with the Lie groups U(1) and SU(2). For reasons of space the present article only includes lectures 1, 2 and 3. Lectures 4 and 5 will be published in a forthcoming paper. (Author)
Directory of Open Access Journals (Sweden)
Masataka Deie
2015-01-01
Full Text Available Background. Posterior cruciate ligament (PCL injuries are not rare in acute knee injuries, and several recent anatomical studies of the PCL and reconstructive surgical techniques have generated improved patient results. Now, we have evaluated PCL reconstructions performed by either the single-bundle or double-bundle technique in a patient group followed up retrospectively for more than 10 years. Methods. PCL reconstructions were conducted using the single-bundle (27 cases or double-bundle (13 cases method from 1999 to 2002. The mean age at surgery was 34 years in the single-bundle group and 32 years in the double-bundle group. The mean follow-up period was 12.5 years. Patients were evaluated by Lysholm scoring, the gravity sag view, and knee arthrometry. Results. The Lysholm score after surgery was 89.1±5.6 points for the single-bundle group and 91.9±4.5 points for the double-bundle group. There was no significant difference between the methods in the side-to-side differences by gravity sag view or knee arthrometer evaluation, although several cases in both groups showed a side-to-side difference exceeding 5 mm by the latter evaluation method. Conclusions. We found no significant difference between single- and double-bundle PCL reconstructions during more than 10 years of follow-up.
Phase Space Reduction of Star Products on Cotangent Bundles.
N. Kowalzig; N. Neumaier; M. Pflaum
2005-01-01
In this paper we construct star products on Marsden-Weinstein reduced spaces in case both the original phase space and the reduced phase space are (symplectomorphic to) cotangent bundles. Under the assumption that the original cotangent bundle $T^*Q$ carries a symplectic structure of form $\\omega_{B
The 2-Hilbert Space of a Prequantum Bundle Gerbe
Bunk, Severin; Szabo, Richard J
2016-01-01
We construct a prequantum 2-Hilbert space for any line bundle gerbe whose Dixmier-Douady class is torsion. Analogously to usual prequantisation, this 2-Hilbert space has the category of sections of the line bundle gerbe as its underlying 2-vector space. These sections are obtained as certain morphism categories in Waldorf's version of the 2-category of line bundle gerbes. We show that these morphism categories carry a monoidal structure under which they are semisimple and abelian. We introduce a dual functor on the sections, which yields a closed structure on the morphisms between bundle gerbes and turns the category of sections into a 2-Hilbert space. We discuss how these 2-Hilbert spaces fit various expectations from higher prequantisation. We then extend the transgression functor to the full 2-category of bundle gerbes and demonstrate its compatibility with the additional structures introduced. We discuss various aspects of Kostant-Souriau prequantisation in this setting, including its dimensional reductio...
Crosstalk analysis of carbon nanotube bundle interconnects
Zhang, Kailiang; Tian, Bo; Zhu, Xiaosong; WANG, FANG; Wei, Jun
2012-01-01
Carbon nanotube (CNT) has been considered as an ideal interconnect material for replacing copper for future nanoscale IC technology due to its outstanding current carrying capability, thermal conductivity, and mechanical robustness. In this paper, crosstalk problems for single-walled carbon nanotube (SWCNT) bundle interconnects are investigated; the interconnect parameters for SWCNT bundle are calculated first, and then the equivalent circuit has been developed to perform the crosstalk analys...
An experimental assessment of cooling of a 54-rod bundle by in-bundle injection
International Nuclear Information System (INIS)
Highlights: ► Rewetting of a 54-rod bundle assembled with a central coolant tube is investigated. ► The coolant tube injects the coolant radially outwards at different axial levels. ► Above a minimum flow rate, coolant quenches all the rods throughout their length. ► Rapid cooling of rods occurs up to around 100 °C of the rod surface temperature. ► Counter current flow of steam–water gets generated which affects cooling adversely. - Abstract: The performance of an in-bundle coolant injection system for the quenching of dry heated rods has been experimentally investigated. The rod bundle contains 54 fuel rods of 11.2 mm diameter, 3700 mm long, arranged in three concentric rings with a central coolant supply tube. The coolant tube supplies the coolant in the form of jets through a series of circumferential holes at different axial levels inside the rod bundle. Visualization during cold state injection tests ensures that the liquid spray can reach different levels of all the rods above a certain flow rate of water through the coolant tube. Extensive cooling experiments were done to assess the suitability of the proposed scheme of in-bundle coolant injection. Time–temperature curves have been derived from rods at different locations, from different heights of the rods, over a range of coolant flow rate as well as for different rod temperatures. The effect of the presence of the spacers on local cooling has also been investigated. The cooling curves follow a general trend of a rapid temperature drop up to almost 100 °C of the rod surface temperature irrespective of the operating parameters and the location of the rod. Thereafter, the temperature falls slowly reaching the coolant temperature almost asymptotically. Moreover, the second phase of cooling is often marked by temperature fluctuations of random nature. It was also observed that a large volume of steam generates during cooling and comes out through the top of the test section expelling a
Effect of Reynolds number and bundle geometry on the turbulent flow in tight lattice bundle
International Nuclear Information System (INIS)
The flow structure in tight lattice is still of great interest to nuclear industry. The accurate prediction of flow parameter in subchannels of tight lattice is likable. Unsteady Reynolds Averaged Navier Stokes (URANS) is a promising approach to achieve this goal. The implementation of URANS (Unsteady Reynolds Averaged Navier Stokes) approach will be validated by comparing computational results with the experimental data of Krauss (1998). In this paper, the turbulent flow with different Reynolds number (5000~215000) and different P/D(1.005~1.2) are simulated with CFD code CFX12.The effects of the Reynolds number and the bundle geometry(P/D) on wall shear stress, turbulent kinetic energy, turbulent mixing and large scale coherent structure in tight lattice are analyzed in details. It is hoped that the present work will contribute to the understanding of these important flow phenomena and facilitate the prediction and design of rod bundles. (author)
Simon Newcomb, Other Aspects of His Career
Corbin, Brenda G.
2014-01-01
Simon Newcomb (1835-1909) is perhaps the best known American astronomer of the late 19th century. Among the many aspects of his long career, he was one of the founders and the first president of what later became the American Astronomical Society. However, he wrote widely on subjects other than astronomy, even producing works of fiction. He was especially interested in economics and published such titles as A critical examination of our financial policy during the Southern rebellion, A plain man's talk on the labor question, Principles of political economy and others. The very interesting title, A statistical inquiry into the probability of causes of the production of sex in human offspring was written in 1904. Newcomb even produced a work of science fiction, His Wisdom, the Defender: a story, published in 1900. William Alvord, President of the Astronomical Society of the Pacific, on awarding Newcomb the Bruce Medal stated “The essential quality of his mind is that of a philosopher rather than that of a mathematician or an astronomer merely.” It has been suggested (Bradley Schaefer and others) that Arthur Conan Doyle used Newcomb as the model for Prof. Moriarty in his Sherlock Holmes novels. He had close friendships with many scientists of his time including Alexander Graham Bell. On the other hand, it has been reported that he also had contentious relationships with some scientists and could be intimidating. A devoted family man, he encouraged his three daughters in their intellectual pursuits. Newcomb, who held naval rank in the Corps of Professors of Mathematics, was buried in Arlington National Cemetery with full military honors. His funeral was attended by many noted scientists and other dignitaries including President William Howard Taft.
On separation axioms of uniform bundles and sheaves
Clara M. Neira U.; Januario Varela
2004-01-01
In the context of the theory of uniform bundles in the sense of J. Dauns and K. H. Hofmann, the topology of the fiber space of a uniform bundle depends on the assumption of upper semicontinuity of its defining set of pseudometrics when composed with local sections. In this paper we show that the additional hypothesis of lower semicontinuity of these functions secures that the fiber space of the uniform bundle is Hausdorff, regular or completely regular provided that the base space has the cor...
The Geometry of Tangent Bundles: Canonical Vector Fields
Directory of Open Access Journals (Sweden)
Tongzhu Li
2013-01-01
Full Text Available A canonical vector field on the tangent bundle is a vector field defined by an invariant coordinate construction. In this paper, a complete classification of canonical vector fields on tangent bundles, depending on vector fields defined on their bases, is obtained. It is shown that every canonical vector field is a linear combination with constant coefficients of three vector fields: the variational vector field (canonical lift, the Liouville vector field, and the vertical lift of a vector field on the base of the tangent bundle.
On the existence of n-dimensional indecomposable vector bundles
International Nuclear Information System (INIS)
Let X be an arbitrary smooth irreducible complex projective curve of genus g with g ≥ 4. In this paper we extend the existence theorem of special divisors to high dimensional indecomposable vector bundles. We give a necessary and sufficient condition on the existence of n-dimensional indecomposable vector bundles E with deg(E) = d, dimH0(X,E) ≥ h. We also determine under what condition the set of all such vector bundles will be finite and how many elements it contains. (author). 9 refs
The Assurance of CHRIST to His followers
Asumadu-Sarkodie, Samuel
2012-01-01
The Assurance of CHRIST to His followers. Assurance: grk. Hupostasis meaning: full and sustained confidence and trust; unwavering conviction. There is a favourite Ghanaian proverb which says "if a naked man says he will clothe you, listen to him quietly". Before someone could assure you of something, he must be self-reliant or independent. Christ Jesus has assured His followers because He is capable, has done it before, continues to do it and will do it. Isaiah 50:4-9a; talks about the qualif...
Eugene Garfield-Glimpses of his writings
Directory of Open Access Journals (Sweden)
B K Sen
2014-01-01
Full Text Available Garfield in his active life used to contribute one article every week which appeared in Current Contents and some renowned journals. The articles thus contributed total around 1500. All these articles had finally appeared in the book called Essays of an Information Scientist in 15 volumes. The present article is based on the first five volumes of his Essays wherein the articles by Garfield have been initially grouped under broad subject headings like Awards, Bibliometric studies, Highly cited articles, etc and then a very brief description has been provided.
Deformation Quantization of Principal Fibre Bundles and Classical Gauge Theories
Wei\\ss, Stefan
2010-01-01
In this dissertation the notion of deformation quantization of principal fibre bundles is established and investigated in order to find a geometric formulation of classical gauge theories on noncommutative space-times. As a generalization, the notion of deformation quantization of surjective submersions is also discussed. It is shown that deformation quantizations of surjective submersions and principal fibre bundles always exist and are unique up to equivalence. These statements concerning complex-valued functions are moreover formulated and proved for sections of arbitrary vector bundles over the total space, in particular equivariant vector bundles. The commutants of the deformed right module structures within the differential operators, playing an inportant role with regard to the infinitesimal gauge transformations, are computed explicitly in each case. Depending on the choice of specific covariant derivatives and connections the commutants are isomorphic to the formal power series of the respective vert...
Steric effects induce geometric remodeling of actin bundles in filopodia
Dobramysl, Ulrich; Erban, Radek
2016-01-01
Filopodia are ubiquitous fingerlike protrusions, spawned by many eukaryotic cells, to probe and interact with their environments. Polymerization dynamics of actin filaments, comprising the structural core of filopodia, largely determine their instantaneous lengths and overall lifetimes. The polymerization reactions at the filopodial tip require transport of G-actin, which enter the filopodial tube from the filopodial base and diffuse toward the filament barbed ends near the tip. Actin filaments are mechanically coupled into a tight bundle by cross-linker proteins. Interestingly, many of these proteins are relatively short, restricting the free diffusion of cytosolic G-actin throughout the bundle and, in particular, its penetration into the bundle core. To investigate the effect of steric restrictions on G-actin diffusion by the porous structure of filopodial actin filament bundle, we used a particle-based stochastic simulation approach. We discovered that excluded volume interactions result in partial and the...
Mechanical Models of Microtubule Bundle Collapse in Alzheimer's Disease
Sendek, Austin; Singh, Rajiv; Cox, Daniel
2013-03-01
Amyloid-beta aggregates initiate Alzheimer's disease, and downstream trigger degradation of tau proteins that act as microtubule bundle stabilizers and mechanical spacers. Currently it is unclear which of tau cutting by proteases, tau phosphorylation, or tau aggregation are responsible for cytoskeleton degradation., We construct a percolation simulation of the microtubule bundle using a molecular spring model for the taus and including depletion force attraction between microtubules and membrane/actin cytoskeletal surface tension. The simulation uses a fictive molecular dynamics to model the motion of the individual microtubules within the bundle as a result of random tau removal, and calculates the elastic modulus of the bundle as the tau concentration falls. We link the tau removal steps to kinetic tau steps in various models of tau degradation. Supported by US NSF Grant DMR 1207624
Design and verification of the 'GURI 01' bundle model
International Nuclear Information System (INIS)
This work presents a general description of the 'GURI 01' bundle model, designed by INVAP S.E., under international radioactive material transportation regulations, as a B(U) type bundle for international transportation up to a maximum of 350000 Ci of Co60. Moreover, the methodologies used and the results obtained from the structural evaluation of the mechanic essay and from the evaluation of the thermal behaviour under normal or accident conditions are briefly discussed. (Author)
Design and synthesis of DNA four-helix bundles
Energy Technology Data Exchange (ETDEWEB)
Rangnekar, Abhijit; Gothelf, Kurt V [Department of Chemistry, Centre for DNA Nanotechnology (CDNA) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C (Denmark); LaBean, Thomas H, E-mail: kvg@chem.au.dk, E-mail: thl@cs.duke.edu [Department of Chemistry, Duke University, Durham, NC 27708 (United States)
2011-06-10
The field of DNA nanotechnology has evolved significantly in the past decade. Researchers have succeeded in synthesizing tile-based structures and using them to form periodic lattices in one, two and three dimensions. Origami-based structures have also been used to create nanoscale structures in two and three dimensions. Design and construction of DNA bundles with fixed circumference has added a new dimension to the field. Here we report the design and synthesis of a DNA four-helix bundle. It was found to be extremely rigid and stable. When several such bundles were assembled using appropriate sticky-ends, they formed micrometre-long filaments. However, when creation of two-dimensional sheet-like arrays of the four-helix bundles was attempted, nanoscale rings were observed instead. The exact reason behind the nanoring formation is yet to be ascertained, but it provides an exciting prospect for making programmable circular nanostructures using DNA.
Analysis of CHF experiment data for finned fuel bundle
International Nuclear Information System (INIS)
The HANARO uses finned-element fuel bundles. For thermal-hydraulic safety analysis, used is the MATRA-h code which is a modified version of KAERI's MATRA-α. The subchannel analysis model was determined by using the in-core irradiation test results and hydraulic experiment results for fuel bundle. The validity of the analysis model was investigated by comparing the MATRA-h predictions with the experimental results from several bundle CHF tests. The comparison showed that the code predictions for the CHF power were very close to or less than the experimental results. Thus, it was confirmed that the subchannel analysis using MATRA-h is to be applicable to the prediction of CHF phenomenon in HANARO fuel bundle
Bundles of Norms About Teen Sex and Pregnancy.
Mollborn, Stefanie; Sennott, Christie
2015-09-01
Teen pregnancy is a cultural battleground in struggles over morality, education, and family. At its heart are norms about teen sex, contraception, pregnancy, and abortion. Analyzing 57 interviews with college students, we found that "bundles" of related norms shaped the messages teens hear. Teens did not think their communities encouraged teen sex or pregnancy, but normative messages differed greatly, with either moral or practical rationalizations. Teens readily identified multiple norms intended to regulate teen sex, contraception, abortion, childbearing, and the sanctioning of teen parents. Beyond influencing teens' behavior, norms shaped teenagers' public portrayals and post hoc justifications of their behavior. Although norm bundles are complex to measure, participants could summarize them succinctly. These bundles and their conflicting behavioral prescriptions create space for human agency in negotiating normative pressures. The norm bundles concept has implications for teen pregnancy prevention policies and can help revitalize social norms for understanding health behaviors. PMID:25387911
Optimal Bundle of Multimedia Services in Emerging Mobile Markets
Lee, ChanGi; Lee, SeongCheol; Lee, DeockHee; Lee, HyeongJik
2006-01-01
Although various emerging technologies have been launched, they present limitations as far as offering full-scale ubiquitous services independently is concerned. In view of this fact, service providers are likely to provide bundled services among possible combinations of services. Indeed, making a timely decision regarding the value maximization of bundled service is directly related to service providers' future growth and success in the turbulent market environment. This paper aims to find t...
A classification of fibre bundles over 2-dimensional spaces
Kubyshin, Yu. A.
1999-01-01
The classification problem for principal fibre bundles over two-dimensional CW-complexes is considered. Using the Postnikov factorization for the base space of a universal bundle a Puppe sequence that gives an implicit solution for the classification problem is constructed. In cases, when the structure group $G$ is path-connected or $\\pi_{1}(G) = 0$, the classification can be given in terms of cohomology groups.
Design and fabrication of a remote fuel bundle welding system
International Nuclear Information System (INIS)
A remote fuel bundle welding system in the hot-cell was designed and fabricated. To achieve this, a preliminary investigation of a hands-on fuel fabrication outside the hot-cell was conducted with a consideration of the constraints caused by welding in the hot-cell. Some basic experiments were also carried out to improve the end-plate welding process for fuel bundle manufacturing. The resistance welding system using the end-plate welding was also improved. It was found that resistance welding was more suitable for joining and end-plate to end caps in the hot-cell. The optimum conditions for end-plate welding for remote operation were also obtained. Preliminary performances to improve the resistance welding process were also examined, and the resistance welding process was determined to be the best in the hot-cell environment for fuel bundle manufacturing. The greatest advantage of fuel bundle welding system would be a qualified process for resistance welding in which there is extensive production experience. This paper presents an outline of the developed welding system for fuel bundle manufacturing and reviews the conceptual design of remote welding system using a master-slave manipulator. The design of a remote welding system using the 3-dimensional modeling method was also designed. Furthermore the mechanical considerations and the mock-up simulation test were described. Finally, its performance test results were presented for a mock-up of a remote fuel bundle welding system. (Author)
Fuel temperature characteristics of the 37-element and CANFLEX fuel bundle
International Nuclear Information System (INIS)
This report describes the fuel temperature characteristics of CANFLEX fuel bundles and 37-element fuel bundles for a different burnup of fuel. The program was consisted for seeking the fuel temperature of fuel bundles of CANFLEX fuel bundles and 37-element fuel bundles by using the method in NUCIRC. Fuel temperature has an increasing pattern with the burnup of fuel for CANFLEX fuel bundles and 37-element fuel bundles. For all the case of burnup, the fuel temperature of CANFLEX fuel bundles has a lower value than that of 37-element fuel bundles. Especially, for the high power channel, the CANFLEX fuel bundles show a lower fuel temperature as much as about 75 degree, and the core averaged fuel temperature has a lower fuel temperature of about 50 degree than that of 37-element fuel bundles. The lower fuel temperature of CANFLEX fuel bundles is expected to enhance the safety by reducing the fuel temperature coefficient. Finally, for each burnup of CANFLEX fuel bundles and 37-element fuel bundles, the equation was present for predicting the fuel temperature of a bundle in terms of a coolant temperature and bundle power
How Buyers Evaluate Product Bundles: A Model of Anchoring and Adjustment.
Yadav, Manjit S
1994-01-01
Bundling, the joint offering of two or more items, is a common selling strategy, yet little research has been conducted on buyers' evaluation of bundle offers. We developed and tested a model of bundle evaluation in which the buyers anchored their evaluation on the item perceived as most important and then made adjustments on the basis of their evaluations of the remaining bundle items. The results of two computerized laboratory experiments suggested that people tend to examine bundle items i...
Thermal hydraulics of rod bundles: The effect of eccentricity
International Nuclear Information System (INIS)
Highlights: • Present CFD investigation explores, whole bundle eccentricity for the first time. • Fluid flow and thermal characteristics in various subchannels are analyzed. • Mass flux distribution is particularly analyzed to study eccentricity effect. • Higher eccentricity resulted in a shoot up in rod surface temperature distribution. • Both tangential and radial flow in rod bundles has resulted due to eccentricity. -- Abstract: The effect of eccentricity on the fluid flow and heat transfer through a 19-rod bundle is numerically carried out. When the whole bundle shifts downwards with respect to the outer (pressure) tube, flow redistribution happens. This in turn is responsible for changes in mass flux, pressure and differential flow development in various subchannels. The heat flux imposed on the surface of the fuel rods and the mass flux through the subchannels determines the coolant outlet temperatures. The simulations are performed for a coolant flow Reynolds number of 4 × 105. For an eccentricity value of 0.7, the mass flux in the bottom most subchannel (l) was found to decrease by 10%, while the surface temperature of the fuel rod in the vicinity of this subchannel increased by 250% at the outlet section. Parameters of engineering interest including skin friction coefficient, Nusselt number, etc., have been systematically explored to study the effect of eccentricity on the rod bundle
Jacobi Matthias; Magnussen Robert A; Villa Vincent; Demey Guillaume; Neyret Philippe
2012-01-01
Abstract Background There is significant interest in the restoration of the double-bundle anatomy of the native ACL when performing ACL reconstruction. Possible techniques include those utilizing two separate grafts with independent tunnels and those that attempt to mimic this anatomy with a single graft and fewer tunnels. Many of the latter techniques require specific instrumentation and are technically challenging. We demonstrate that the double-bundle anatomy of the native ACL can theoreti...
Hagg, Heather (Woodward); El-Harit, Jamie; Vanni, Chris; Scott, Penny
2007-01-01
Within healthcare, clinical practice bundles have been used to implement standardized, nursing driven protocols resulting in standardized patient care and improved patient outcomes. Examples of these types of bundles include clinical practices shown through evidence based medicine to reduce occurrences of Ventilator Associated Pneumonia – VAP bundle; those shown to reduce the occurrences of central line infections – CL bundle; and those shown to significantly improve the outcomes of patients...
Failure process of a bundle of plastic fibers
F. Raischel; Kun, F; Herrmann, H. J.
2006-01-01
We present an extension of fiber bundle models considering that failed fibers still carry a fraction $0 \\leq \\alpha \\leq 1$ of their failure load. The value of $\\alpha$ interpolates between the perfectly brittle failure $(\\alpha = 0)$ and perfectly plastic behavior $(\\alpha=1)$ of fibers. We show that the finite load bearing capacity of broken fibers has a substantial effect on the failure process of the bundle. In the case of global load sharing it is found that for $\\alpha \\to 1$ the macros...
Modelling of transient dynamic bundle deformation using time integration scheme
International Nuclear Information System (INIS)
The BOW code has been examined whether its modeling capability can be extended to the simulation of interactions (i.e., fretting) between neighbouring fuel elements in a fuel bundle and between the fuel bundle and the pressure tube in a fuel channel. The current BOW code is specialized in simulating the static problems, such as the deflection of each element and interactions between neighbouring elements in a fuel bundle, and interactions between neighbouring bundles and between a bundle and the pressure tube in a fuel channel. The Wilson θ time integration scheme has been implemented in the BOW code, for the extension of its capability to modelling dynamic contact problems. As part of verification to ensure that the modification in the code functions exactly as designed, the dynamic-modelling capability of the BOW code has been applied to simple support beam cases subjected to a uniform step load at the middle of the beam. The calculation results confirmed that the modified BOW code, where the contact algorithm is implemented in the step-by-step integration manner using the Wilson θ time integration scheme, can solve the dynamic problem with unconditional convergence. This paper describes the theory and models for the new capabilities of the BOW code. (author)
Location of test bundle instrumentation and anticipated experimental values for the CFTL AG-1 bundle
International Nuclear Information System (INIS)
The placement of instrumentation within the Core Flow Test Loop (CFTL) AG-1 test section to meet the following objectives is described. The objectives are threefold: (1) to provide values for the evaluation of the performance of the test section, (2) to compare the experimental data with value determined by pretest calulations to indicate the approach to conditions that can lead to a bundle failure, and (3) to acquire data during testing that will form a data base for subsequent use in the verification of computational procedures used in the licensing of the Gas-Cooled Fast Reactor. Anticipated values for the various instruments have been determined using the computational procedure SAGAPO modified for the AG-1 geometry. These results are used as the basis for the specification of differential pressure cells and the range of readings anticipated from the thermocouples. Part of the results for the full-flow, full-power case is presented
Experimental study for convective heat transfer of staged tube bundles
International Nuclear Information System (INIS)
The lack of potable water is one of the most serious problems the world is facing at present. SMART which is a 330 MWt advanced integral PWR, was developed by the KAERI for electricity generation and seawater desalination. SMART adopted a passive system to enhance its safety. The passive system can passively remove a decay heat from a reactor core to an emergency cooldown tank through the heat exchanger. Tube bundles of the heat exchanger, which is submerged in an emergency cooldown tank, transfer heat to an emergency cooldown tank by natural circulation. Heat transfer tests for the upward straight tube bundle were performed to confirm the capability of the SMART design under natural circulation conditions. The heat transfer at the tube bundle was affected by the fluid temperature in the emergency cooldown tank and the radial location of tube bundle. However, it had nearly the same value at the inlet region regardless of the tube location. The average heat transfer at the tube bundle was slightly higher than that at the single tube. (author)
Multi-scale strain-stiffening of semiflexible bundle networks
Piechocka, I K; Broedersz, C P; Kurniawan, N A; MacKintosh, F C; Koenderink, G H
2015-01-01
Bundles of polymer filaments are responsible for the rich and unique mechanical behaviors of many biomaterials, including cells and extracellular matrices. In fibrin biopolymers, whose nonlinear elastic properties are crucial for normal blood clotting, protofibrils self-assemble and bundle to form networks of semiflexible fibers. Here we show that the extraordinary strain-stiffening response of fibrin networks is a direct reflection of the hierarchical architecture of the fibrin fibers. We measure the rheology of networks of unbundled protofibrils and find excellent agreement with an affine model of extensible wormlike polymers. By direct comparison with these data, we show that physiological fibrin networks composed of thick fibers can be modeled as networks of tight protofibril bundles. We demonstrate that the tightness of coupling between protofibrils in the fibers can be tuned by the degree of enzymatic intermolecular crosslinking by the coagulation Factor XIII. Furthermore, at high stress, the protofibri...
Study Of The PWR Fuel Bundle Characteristic With Borated Water
International Nuclear Information System (INIS)
Study of the PWR fuel bundle characteristic with 2,4, 2,6, 2,8, 3,0, 3,2 and 3,4 enrichment also with borated water 150 and 200 ppm has been done. The fuel bundle contained 264 fuel elements and water (no fuel elements) are arranged as 17 x 17 matrix and 30,294 cm. The fuel bundle characteristic can be seen from their group constants and the infinite multiplication factor whether more or less than one. The fuel bundle parameters can be found from cell calculation with WIMS PC version program. From the cell calculation shown that the infinite multiplication factor of the fuel bundle with 2,4% enrichment and 200 ppm borated water is 1, 01672, its shown that infinite multiplication factor will less than one with increasing borated water more than 200 ppm. From these result if we would like to design the reactor core with 2,4% minimum enrichment then the maximum borated water is 200 ppm
Magnetic Propulsion of Microswimmers with DNA-Based Flagellar Bundles.
Maier, Alexander M; Weig, Cornelius; Oswald, Peter; Frey, Erwin; Fischer, Peer; Liedl, Tim
2016-02-10
We show that DNA-based self-assembly can serve as a general and flexible tool to construct artificial flagella of several micrometers in length and only tens of nanometers in diameter. By attaching the DNA flagella to biocompatible magnetic microparticles, we provide a proof of concept demonstration of hybrid structures that, when rotated in an external magnetic field, propel by means of a flagellar bundle, similar to self-propelling peritrichous bacteria. Our theoretical analysis predicts that flagellar bundles that possess a length-dependent bending stiffness should exhibit a superior swimming speed compared to swimmers with a single appendage. The DNA self-assembly method permits the realization of these improved flagellar bundles in good agreement with our quantitative model. DNA flagella with well-controlled shape could fundamentally increase the functionality of fully biocompatible nanorobots and extend the scope and complexity of active materials. PMID:26821214
Symposium on Singularities, Representation of Algebras, and Vector Bundles
Trautmann, Günther
1987-01-01
It is well known that there are close relations between classes of singularities and representation theory via the McKay correspondence and between representation theory and vector bundles on projective spaces via the Bernstein-Gelfand-Gelfand construction. These relations however cannot be considered to be either completely understood or fully exploited. These proceedings document recent developments in the area. The questions and methods of representation theory have applications to singularities and to vector bundles. Representation theory itself, which had primarily developed its methods for Artinian algebras, starts to investigate algebras of higher dimension partly because of these applications. Future research in representation theory may be spurred by the classification of singularities and the highly developed theory of moduli for vector bundles. The volume contains 3 survey articles on the 3 main topics mentioned, stressing their interrelationships, as well as original research papers.
Directory of Open Access Journals (Sweden)
Мирко Обрадовић
2011-12-01
Full Text Available This paper examines the tradition about Bias of Priene, one of the Seven Wise Men of Greece about whom many stories were told, his background and the meaning of his name. In the absence of reliable historical sources, testimonia mostly come from a variety of disparate sources compiled in Hellenistic times or later and we may only suppose that local anecdotes, proverbs and short sayings reflect historical events. The paper provides detailed treatment of the several conflicting traditions about Bias of Priene. Nevertheless, the surviving biographical information about Bias point to the period of the reign of King Croesus and the Persian conquest of Asia Minor (ca. 560–540 BC, as the best time of his political activity. For this reason he might be designated as the sixth-century philosopher and statesman who was a generation younger than most others from among the Seven Sages (e.g. Solon of Athens, Thales of Miletus, Pittacus of Mytilene, Periander of Corinth. In the second part of the paper the possible meaning of the name Bias has been examined. This name as a personal name was almost certainly taken from the heroic repertoire of Greek names with an intention of connecting Bias’s family, who obviously belonged to the aristocracy of Priene, with the world of heroes, and through them, with the world of gods. The most famous mythical bearer of the name Bias was the hero Bias, the son of Amythaon and the brother of the legendary seer and healer Melampus. This Bias married Pero, the daughter of Neleus, the founder of Pylos in Messenia, and he had with her glorious offspring, before he settled in Argos. The choice of that heroic name as a personal name in the family of the wise Prienian might not be by chance, and it can be best explained with possible Neleid and Messenian connections generally existing among the local aristocracy in the Ionian poleis of the Archaic period. These connections were quite expected because the Neleids were ubiquitous
A vector bundle proof of Poncelet theorem
Vallès, Jean
2012-01-01
In the town of Saratov where he was prisonner, Poncelet, continuing the work of Euler and Steiner on polygons simultaneously inscribed in a circle and circumscribed around an other circle, proved the following generalization : "Let C and D be two smooth conics in the projective complex plane. If D passes through the n(n-1)/2 vertices of a complete polygon with n sides tangent to C then D passes through the vertices of infinitely many such polygons." According to Marcel Berger this theorem is the nicest result about the geometry of conics. Even if it is, there are few proofs of it. To my knowledge there are only three. The first proof, published in 1822 and based on infinitesimal deformations, is due to Poncelet. Later, Jacobi proposed a new proof based on finite order points on elliptic curves; his proof, certainly the most famous, is explained in a modern way and in detail by Griffiths and Harris. In 1870 Weyr proved a Poncelet theorem in space (more precisely for two quadrics) that implies the one above whe...
Simulation of bundle test Quench-12 with integral code MELCOR
International Nuclear Information System (INIS)
The past NRI analyses cover the Quench-01, Quench-03 and Quench-06 with version MELCOR 1.8.5 (including reflood model), and Quench-01 and Quench-11 tests with the latest version MELCOR 1.8.6. The Quench-12 test is specific, because it has different bundle configuration related to the VVER bundle configuration with hexagonal grid of pins and also used E110 cladding material. Specificity of Quench-12 test is also in the used material of fuel rod cladding - E110. The test specificities are a reason for the highest concern, because the VVER reactors are operated in the Czech Republic. The new input model was developed with the taking into account all experience from previous simulations of the Quench bundle tests. The recent version MELCOR 1.8.6 YU2911 was used for the simulation with slightly modified ELHEAT package. Sensitivity studies on input parameters and oxidation kinetics were performed. (author)
Directory of Open Access Journals (Sweden)
Sandra Umeda Sasaki
2008-01-01
Full Text Available INTRODUCTION: Anterior cruciate ligament ruptures are frequent, especially in sports. Surgical reconstruction with autologous grafts is widely employed in the international literature. Controversies remain with respect to technique variations as continuous research for improvement takes place. One of these variations is the anatomical double bundle technique, which is performed instead of the conventional single bundle technique. More recently, there has been a tendency towards positioning the two bundles through double bone tunnels in the femur and tibia (anatomical reconstruction. OBJECTIVES: To compare, through biomechanical tests, the practice of anatomical double bundle anterior cruciate ligament reconstruction with a patellar graft to conventional single bundle reconstruction with the same amount of patellar graft in a paired experimental cadaver study. METHODS: Nine pairs of male cadaver knees ranging in age from 44 to 63 years were randomized into two groups: group A (single bundle and group B (anatomical reconstruction. Each knee was biomechanically tested under three conditions: intact anterior cruciate ligament, reconstructed anterior cruciate ligament, and injured anterior cruciate ligament. Maximum anterior dislocation, rigidity, and passive internal tibia rotation were recorded with knees submitted to a 100 N horizontal anterior dislocation force applied to the tibia with the knees at 30, 60 and 90 degrees of flexion. RESULTS: There were no differences between the two techniques for any of the measurements by ANOVA tests. CONCLUSION: The technique of anatomical double bundle reconstruction of the anterior cruciate ligament with bone-patellar tendon-bone graft has a similar biomechanical behavior with regard to anterior tibial dislocation, rigidity, and passive internal tibial rotation.
Stable bundles of rank 2 with 4 sections
Grzegorczyk, I; Newstead, P E
2010-01-01
This paper contains results on stable bundles of rank $2$ with space of sections of dimension $4$ on a smooth irreducible projective algebraic curve $C$. There is a known lower bound on the degree for the existence of such bundles; the main result of the paper is a geometric criterion for this bound to be attained. For a general curve $C$ of genus $10$, we show that the bound cannot be attained, but that there exist Petri curves of this genus for which the bound is sharp. We interpret the main results for various curves and in terms of Clifford indices and coherent systems.
Evaluation of phenomenological DNB models for rod bundle geometries
International Nuclear Information System (INIS)
Seven phenomenological DNB models based on the liquid sublayer dryout and the bubble crowding mechanisms have been evaluated for the square array rod bundles at PWR conditions. The local thermal hydraulic conditions were calculated by the COBRA-IV-I code, and it was assumed that the enthalpy and mass velocity distribution in the test bundle would not be changed at different power levels. A simplified method, which has been proposed for the prediction of CHF in rod bundles from round tube CHF correlations without detailed subchannel analyses, was also applied with the phenomenological models. In view of the prediction accuracy and the applicable range, Lin model shows the best result among phenomenological DNB models assessed in this study. The parametric trends of phenomenological DNB models, however are somewhat abnormal comparing to experimental data. So it can be argued that the existing phenomenological DNB models are rather empirical than theoretical so far
Stable bundles of rank 2 with 4 sections
Grzegorczyk, I.; Mercat, V.; Newstead, P. E.
2010-01-01
This paper contains results on stable bundles of rank 2 with space of sections of dimension 4 on a smooth irreducible projective algebraic curve $C$. There is a known lower bound on the degree for the existence of such bundles; the main result of the paper is a geometric criterion for this bound to be attained. For a general curve $C$ of genus 10, we show that the bound cannot be attained, but that there exist Petri curves of this genus for which the bound is sharp. We interpret the main resu...
Bohr--Sommerfeld Lagrangians of moduli spaces of Higgs bundles
DEFF Research Database (Denmark)
Biswas, Indranil; Gammelgaard, Niels Leth; Logares, Marina
Let $X$ be a compact connected Riemann surface of genus at least two. Let $M_H(r,d)$ denote the moduli space of semistable Higgs bundles on $X$ of rank $r$ and degree $d$. We prove that the compact complex Bohr-Sommerfeld Lagrangians of $M_H(r,d)$ are precisely the irreducible components of the n...
ASSERT and COBRA predictions of flow distribution in vertical bundles
International Nuclear Information System (INIS)
COBRA and ASSERT are subchannel codes which compute flow and enthalpy distributions in rod bundles. COBRA is a well known code, ASSERT is under development at CRNL. This paper gives a comparison of the two codes with boiling experiments in vertical seven rod bundles. ASSERT predictions of the void distribution are shown to be in good agreement with reported experimental results, while COBRA predictions are unsatisfactory. The mixing models in both COBRA and ASSERT are briefly discussed. The reasons for the failure of COBRA-IV and the success of ASSERT in simulating the experiments are highlighted
The effect of radial power profile of DUPIC bundle on CHF
International Nuclear Information System (INIS)
The axial and ring power profiles of DUPIC bundle are much different from those of reference 37-element fuel bundle since a DUPIC fuel bundle is re-fabricated using spent PWR fuel and 2-bundle shift refuelling scheme is proposed to CANDU-6 reactor. In case that the ring power profile of a fuel bundle is altered, the flow and enthalpy distribution of subchannels and the radial position of CHF occurrence will be changed. Similarly, the axial power profile of a fuel channel affects CHF and axial position of CHF occurrence as well as axial enthalpy, quality and pressure distribution. The ring power profile of the DUPIC bundle as increasing burnup is altered and flattened compared to 37-element bundle and each fuel bundle in a fuel channel has a different ring power profile from the other bundles at different axial position in the same fuel channel. Therefore, how to consider the burnup or ring power effect on CHF is very important to DUPIC thermalhydraulic analysis. At present study, thermalhydraulic analysis of the DUPIC bundle was performed in consideration of ring power profile effect on CHF. The subchannel enthalpy, mass flux and CHF distribution for 0 burnup to discharged burnup (18,000 MWD/THM) of DUPIC bundle were evaluated using ASSERT subchannel code. The results were compared to those of 37-element bundle and the compatability of DUPIC bundle with an existing CANDU-6 was presented in a CHF point of view
Validation of SOCRAT-BN code on rod bundle experiments
International Nuclear Information System (INIS)
SOCRAT-BN code is developed for the analysis of design and beyond design basis accidents at NPPs with liquid sodium as a coolant. To simulate the behavior of the coolant in the reactor core heat transfer and friction in rod bundle geometry are required to consider. The code SOCRAT-BN uses specialized closing relations to simulate rod bundles. The article describes the validation of the code SOCRAT-BN on experiments with fuel rod imitators in the triangular geometry with a wire-wound. (author)
Reaction–diffusion model of hair-bundle morphogenesis
Jacobo, Adrian; Hudspeth, A. J.
2014-01-01
Our senses of hearing and balance rest upon the activity of hair cells, the ear’s sensory receptors. Each hair cell detects mechanical stimuli with its hair bundle, an organelle comprising 10–300 cylindrical, actin-filled stereocilia. A bundle’s structure is highly stereotyped: the stereocilia stand erect in a regular, hexagonal array and display a monotonic gradient in length along one axis. This precise organization is key to the operation of the hair bundle: mutations that disturb the morp...
The Determinant Bundle on the Moduli Space of Stable Triples over a Curve
Indian Academy of Sciences (India)
Indranil Biswas; N Raghavendra
2002-08-01
We construct a holomorphic Hermitian line bundle over the moduli space of stable triples of the form (1, 2, ), where 1 and 2 are holomorphic vector bundles over a fixed compact Riemann surface , and : 2 → 1 is a holomorphic vector bundle homomorphism. The curvature of the Chern connection of this holomorphic Hermitian line bundle is computed. The curvature is shown to coincide with a constant scalar multiple of the natural Kähler form on the moduli space. The construction is based on a result of Quillen on the determinant line bundle over the space of Dolbeault operators on a fixed ∞ Hermitian vector bundle over a compact Riemann surface.
Cohomology of line bundles: Proof of the algorithm
International Nuclear Information System (INIS)
We present a proof of the algorithm for computing line bundle valued cohomology classes over toric varieties conjectured by Blumenhagen et al. [e-print arXiv:cond-mat/1003.5217] and suggest a kind of Serre duality for combinatorial Betti numbers that we observed when computing examples.
Phase Space Reduction of Star Products on Cotangent Bundles
Kowalzig, Niels; Neumaier, Nikolai; Pflaum, Markus J.
2004-01-01
In this paper we construct star products on Marsden-Weinstein reduced spaces in case both the original phase space and the reduced phase space are (symplectomorphic to) cotangent bundles. Under the assumption that the original cotangent bundle $T^*Q$ carries a symplectique structure of form $\\omega_{B_0}=\\omega_0 + \\pi^*B_0$ with $B_0$ a closed two-form on $Q$, is equipped by the cotangent lift of a proper and free Lie group action on $Q$ and by an invariant star product that admits a $G$-equ...
Quillen Bundle and Geometric Prequantization of Non-Abelian Vortices on a Riemann Surface
Indian Academy of Sciences (India)
Rukmini Dey; Samir K Paul
2011-02-01
In this paper we prequantize the moduli space of non-abelian vortices. We explicitly calculate the symplectic form arising from 2 metric and we construct a prequantum line bundle whose curvature is proportional to this symplectic form. The prequantum line bundle turns out to be Quillen’s determinant line bundle with a modified Quillen metric. Next, as in the case of abelian vortices, we construct line bundles over the moduli space whose curvatures form a family of symplectic forms which are parametrized by $\\Psi_0$, a section of a certain bundle. The equivalence of these prequantum bundles are discussed.
Assembly and operation experience of EVA II steam reforming bundle
International Nuclear Information System (INIS)
The main test component of the experimental facility EVA-II/ADAM-II is a helium heated steam reformer bundle with 30 tubes. The tubes are filled with a catalyst of raschig ring type. The main test of the component were related to the power dependence. A series of experiment dealt with the influence of steam/methane ratio on the carbon deposit formation
A Method of Assembling Compact Coherent Fiber-Optic Bundles
Martin, Stefan; Liu, Duncan; Levine, Bruce Martin; Shao, Michael; Wallace, James
2007-01-01
A method of assembling coherent fiber-optic bundles in which all the fibers are packed together as closely as possible is undergoing development. The method is based, straightforwardly, on the established concept of hexagonal close packing; hence, the development efforts are focused on fixtures and techniques for practical implementation of hexagonal close packing of parallel optical fibers.
On Liftings of Local Torus Actions to Fiber Bundles
Yoshida, Takahiko
2007-01-01
In this note we define a lifting of a local torus action modeled on the standard representation (we call it a local torus action for simplicity) to a principal torus bundle, and show that there is an obstruction class for the existence of liftings in the first cohomology of the fundamental group of the orbit space with coefficients in a certain module.
Coupling Systems of Five CARA Fuel Bundles for Atucha I
International Nuclear Information System (INIS)
This paper describe the mechanical design of two options for the coupling systems of five CARA fuel bundles, to be used in the Atucha I nuclear power plant. These systems will be hydraulic tested in a low pressure loop to know their hydraulic loss of pressure
Moduli of Parabolic Higgs Bundles and Atiyah Algebroids
DEFF Research Database (Denmark)
Logares, Marina; Martens, Johan
2010-01-01
. By considering the case of full flags, we get a Grothendieck–Springer resolution for all other flag types, in particular for the moduli spaces of twisted Higgs bundles, as studied by Markman and Bottacin and used in the recent work of Laumon–Ngô. We discuss the Hitchin system, and demonstrate that...
Multicell slug flow heat transfer analysis of finite LMFBR bundles
Energy Technology Data Exchange (ETDEWEB)
Yeung, M.K.; Wolf, L.
1978-12-01
An analytical two-dimensional, multi-region, multi-cell technique has been developed for the thermal analysis of LMFBR rod bundles. Local temperature fields of various unit cells were obtained for 7, 19, and 37-rod bundles of different geometries and power distributions. The validity of the technique has been verified by its excellent agreement with the THTB calculational result. By comparing the calculated fully-developed circumferential clad temperature distribution with those of the experimental measurements, an axial correction factor has been derived to account for the entrance effect for practical considerations. Moreover, the knowledge of the local temperature field of the rod bundle leads to the determination of the effective mixing lengths L/sub ij/ for adjacent subchannels of various geometries. It was shown that the implementation of the accurately determined L/sub ij/ into COBRA-IIIC calculations has fairly significant effects on intersubchannel mixing. In addition, a scheme has been proposed to couple the 2-D distributed and lumped parameter calculation by COBRA-IIIC such that the entrance effect can be implanted into the distributed parameter analysis. The technique has demonstrated its applicability for a 7-rod bundle and the results of calculation were compared to those of three-dimensional analyses and experimental measurements.
Self-adjointness of the Gaffney Laplacian on Vector Bundles
International Nuclear Information System (INIS)
We study the Gaffney Laplacian on a vector bundle equipped with a compatible metric and connection over a Riemannian manifold that is possibly geodesically incomplete. Under the hypothesis that the Cauchy boundary is polar, we demonstrate the self-adjointness of this Laplacian. Furthermore, we show that negligible boundary is a necessary and sufficient condition for the self-adjointness of this operator
Heat transfer and fluid friction in bundles of twisted tubes
Dzyubenko, B. V.; Dreitser, G. A.
1986-06-01
The results of heat-transfer and friction studies in bundles of twisted tubes and rods with spiral wire-wrap spacers are analyzed, and recommendations are given for calculating the heat-transfer coefficient in heat exchangers using twisted tubes.
Self-adjointness of the Gaffney Laplacian on Vector Bundles
Energy Technology Data Exchange (ETDEWEB)
Bandara, Lashi, E-mail: lashi.bandara@chalmers.se [Chalmers University of Technology and University of Gothenburg, Mathematical Sciences (Sweden); Milatovic, Ognjen, E-mail: omilatov@unf.edu [University of North Florida, Department of Mathematics and Statistics (United States)
2015-12-15
We study the Gaffney Laplacian on a vector bundle equipped with a compatible metric and connection over a Riemannian manifold that is possibly geodesically incomplete. Under the hypothesis that the Cauchy boundary is polar, we demonstrate the self-adjointness of this Laplacian. Furthermore, we show that negligible boundary is a necessary and sufficient condition for the self-adjointness of this operator.
An extension theorem of Ohsawa-Takegoshi type for sections of a vector bundle
Raufi, Hossein
2014-01-01
Using $L^2$-methods for the $\\bar\\partial$-equation we prove that the Ohsawa-Takegoshi extension theorem also holds for holomorphic sections of a vector bundle, over compact K\\"ahler manifolds. We then proceed to show that the conditions that are needed are more liberal than the ones one would need if one instead reduced the extension problem to line bundles through the usual algebraic geometric procedure of studying the projective bundle associated with the vector bundle.
Vibrations of turbine blades bundles model with rubber damping elements
Czech Academy of Sciences Publication Activity Database
Půst, Ladislav; Pešek, Luděk
2014-01-01
Roč. 21, č. 1 (2014), s. 45-52. ISSN 1802-1484 R&D Projects: GA ČR GA101/09/1166 Institutional support: RVO:61388998 Keywords : mathematical model * bundle of five blades * rubber damping elements * eigenmodes Subject RIV: BI - Acoustics http://www.engineeringmechanics.cz/obsahy.html?R=21&C=1
Rigidity of Minimal Submanifolds with Flat Normal Bundle
Indian Academy of Sciences (India)
Hai-Ping Fu
2010-09-01
Let $M^n(n≥ 3)$ be an -dimensional complete immersed $\\frac{n-2}{n}$-superstable minimal submanifold in an $(n+p)$-dimensional Euclidean space $\\mathbb{R}^{n+p}$ with flat normal bundle. We prove that if the second fundamental form of satisfies some decay conditions, then is an affine plane or a catenoid in some Euclidean subspace.
An evaluation on the cutting technologies for decommissioning of the tube bundles in the RPV of NPPs
International Nuclear Information System (INIS)
Highlights: • This paper is to evaluate an optimal cutting technology of the tube bundles in the RPV of NPPs. • Characteristics of the tube bundles were analyzed and alternative cutting technologies of the tube bundles were evaluated. • An optimal cutting technology of the tube bundles was suggested. - Abstract: This paper is to evaluate an optimal cutting technology of the tube bundles in the reactor pressure vessel of nuclear power plants. Characteristics of the tube bundles were analyzed and alternative cutting technologies of the tube bundles were evaluated. The optimal cutting technology of the tube bundles was suggested
Compressive force generation by a bundle of living biofilaments
Ramachandran, Sanoop; Ryckaert, Jean-Paul
2013-08-01
To study the compressional forces exerted by a bundle of living stiff filaments pressing on a surface, akin to the case of an actin bundle in filopodia structures, we have performed particulate molecular dynamics simulations of a grafted bundle of parallel living (self-assembling) filaments, in chemical equilibrium with a solution of their constitutive monomers. Equilibrium is established as these filaments, grafted at one end to a wall of the simulation box, grow at their chemically active free end, and encounter the opposite confining wall of the simulation box. Further growth of filaments requires bending and thus energy, which automatically limit the populations of longer filaments. The resulting filament sizes distribution and the force exerted by the bundle on the obstacle are analyzed for different grafting densities and different sub- or supercritical conditions, these properties being compared with the predictions of the corresponding ideal confined bundle model. In this analysis, non-ideal effects due to interactions between filaments and confinement effects are singled out. For all state points considered at the same temperature and at the same gap width between the two surfaces, the force per filament exerted on the opposite wall appears to be a function of a rescaled free monomer density hat{ρ }_1^eff. This quantity can be estimated directly from the characteristic length of the exponential filament size distribution P observed in the size domain where these grafted filaments are not in direct contact with the wall. We also analyze the dynamics of the filament contour length fluctuations in terms of effective polymerization (U) and depolymerization (W) rates, where again it is possible to disentangle non-ideal and confinement effects.
A comprehensive comparison on vibration and heat transfer of two elastic heat transfer tube bundles
Institute of Scientific and Technical Information of China (English)
闫柯; 葛培琪; 翟强
2015-01-01
Elastic heat transfer tube bundles are widely used in the field of flow-induced vibration heat transfer enhancement. Two types of mainly used tube bundles, the planar elastic tube bundle and the conical spiral tube bundle were comprehensively compared in the condition of the same shell side diameter. The natural mode characteristics, the effect of fluid−structure interaction, the stress distribution, the comprehensive heat transfer performance and the secondary fluid flow of the two elastic tube bundles were all concluded and compared. The results show that the natural frequency and the critical velocity of vibration buckling of the planar elastic tube bundle are larger than those of the conical spiral tube bundle, while the stress distribution and the comprehensive heat transfer performance of the conical spiral tube bundle are relatively better.
Semistability of Certain Bundles on Second Symmetric Power of a Curve
Dan, Krishanu; Pal, Sarbeswar
2015-01-01
Let $C$ be a smooth irreducible projective curve and $E$ be a rank 2 stable vector bundle on $C$. Then one can associate a rank 4 vector bundle $\\mathcal{F}_2(E)$ on $S^2(C)$, second symmetric power of $C$. Our goal in this article is to study semistability of this bundle.
Fuel bundle loss of cooling inside the fuelling machine at CANDU6 PHWR
International Nuclear Information System (INIS)
This article describes the that loss of forced circulation cooling flow of induce spent fuel bundle loss of cooling and fission product releasing, analyzes the effect of reactor building and environment due to the fuel bundle rupturing, discusses the countermeasure to deal with the event of loss of cooling of spent fuel bundle. (authors)
Twisted Partial Actions, A Classification of Stable C*-Algebraic Bundles (Preliminary Version)
Exel, Ruy
1994-01-01
We introduce the notion of continuous twisted partial actions of a locally compact group on a C*-algebra. With such, we construct an associated C*-algebraic bundle called the semidirect product bundle. Our main theorem shows that, given any C*-algebraic bundle which is second countable and whose unit fiber algebra is stable, there is a continuous twisted partial action of the base group on the unit fiber algebra, whose associated semidirect product bundle is isomorphic to the given one.
Equilibrium Bundle Size of Rodlike Polyelectrolytes with Counterion-Induced Attractive Interactions
Henle, Mark L.; Pincus, Philip A.
2004-01-01
Multivalent counterions can induce an effective attraction between like-charged rodlike polyelectrolytes, leading to the formation of polelectrolyte bundles. In this paper, we calculate the equilibrium bundle size using a simple model in which the attraction between polyelectrolytes (assumed to be pairwise additive) is treated phenomenologically. If the counterions are point-like, they almost completely neutralize the charge of the bundle, and the equilibrium bundle size diverges. When the co...
Effect of left bundle branch block on TIMI frame count
Hatice Tolunay; Ahmet Kasapkara; İsa Öner Yüksel; Nurcan Başar; Ayşe Saatcı Yaşar; Mehmet Bilge
2010-01-01
Aim: Left bundle branch block is an independent risk factorfor cardiac mortality. In this study we aimed to evaluatecoronary blood flow with TIMI frame count in patients with left bundle branch block and angiographically proven normal coronary arteries.Materials and methods: We retrospectively studied 17 patients with left bundle branch block and as a control group 16 patients without left bundle branch block. All patientshad angiographically proven normal coronary arteries.Left bundle branch...
The existence of a kind of bundle map
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
3 By means of the theory of Postnikov resolution, a sufficient condition for the existence of a kind of bundle maps is obtained. Some applications of the result are given. Particularly, it is proven that the deleted products as well as configuration spaces of two simply connected manifolds with suitable dimension have the same homotopy type when the original manifolds are homotopically equivalent.
On the Topology of Real Bundle Pairs over Nodal Symmetric Surfaces
Georgieva, Penka
2015-01-01
We give an alternative argument for the classification of real bundle pairs over smooth symmetric surfaces and extend this classification to nodal symmetric surfaces. We also classify the homotopy classes of automorphisms of real bundle pairs over symmetric surfaces. The two statements together describe the isomorphisms between real bundle pairs over symmetric surfaces up to deformation.
Persistence Length and Nanomechanics of Random Bundles of Nanotubes
Energy Technology Data Exchange (ETDEWEB)
Yakobson, Boris I. [Rice University, Department of Mechanical Engineering and Materials Science, Department of Chemistry, and Center for Nanoscale Science and Technology (United States)], E-mail: biy@rice.edu; Couchman, Luise S. [Naval Research Laboratory, Code 7130 (United States)
2006-02-15
A connection between the stiffness of carbon nanotubes (CNT) and their mesoscopic physical behaviour is presented. Persistence lengths of CNT and bundles are calculated and shown to be in macroscopic range (0.03-1 mm for an individual tube), exceeding by many orders of magnitude the typical diameters (around 1-3 nm). Consequently, thermal fluctuations can be neglected when scaling analysis is applied to randomly packed (as produced) CNT network, leading to an approximate equation of state for such material. Beyond the linear elasticity, the outmost CNT are shown to gradually split from the bent bundles; this permits access of solvent or reacting species to the CNT walls, an important mechanism promoting solubilization and chemical functionalization of nanotubes.
Standardization of Type 2 Diabetes Outpatient Expenditure with Bundled Payment Method in China
Directory of Open Access Journals (Sweden)
Guo-Chao Xu
2016-01-01
Conclusions: We argued that it is feasible to implement bundled payment on type 2 diabetes outpatient services. Bundled payment is effective to control the increase of outpatient expenditure. Further improvements are needed for the implementation of bundled payment reimbursement standards, together with relevant policies and measures.
Walker Calhoun: Master of His Art, Keeper of Traditions.
Hoffman, Carl
1993-01-01
During the 1920s, Walker Calhoun learned traditional songs and dances from his uncle, Will West Long, spiritual leader of the Big Cove Cherokees. Nine years ago, Calhoun began teaching them to his grandchildren and other young people. Calhoun has received numerous honors for his work to preserve Cherokee culture. (LP)
Murray, Michael K; Stevenson, Danny; Vozzo, Raymond F
2015-01-01
We develop the theory of simplicial extensions for bundle gerbes and their characteristic classes. This formalism is used to study descent problems and equivariance for bundle gerbes. We consider in detail two examples: the basic bundle gerbe on a unitary group and a string structure for a principal bundle. We show that the basic bundle gerbe is equivariant for the conjugation action and calculate its characteristic class and that a string structure gives rise to a bundle gerbe which is equivariant for a natural action of the String 2-group.
Nikolai N. Anichkov and His Theory of Atherosclerosis
Konstantinov, Igor E.; Mejevoi, Nicolai; Anichkov, Nikolai M.
2006-01-01
Nikolai N. Anichkov (1885–1964) first demonstrated the role of cholesterol in the development of atherosclerosis. His classic experiments in 1913 paved the way to our current understanding of the role of cholesterol in cardiovascular disease. Anichkov's research is often cited among the greatest discoveries of the 20th century; however, little is known about Anichkov and his team. Herein, we give a detailed historical account of Anichkov's work, his personality, his research team, and their p...
Chen, Yongmin; Li, Jianpei
2015-01-01
When procuring multiple products from competing firms, a buyer may choose separate purchase, pure bundling, or mixed bundling. We show that pure bundling will generate higher buyer surplus than both separate purchase and mixed bundling, provided that trade for each good is likely to be efficient. Pure bundling is superior because it intensifies the competition between firms by reducing their cost asymmetry. Mixed bundling is inferior because it allows firms to coordinate to ...
Linear duals of graded bundles and higher analogues of (Lie) algebroids
Bruce, Andrew James; Grabowska, Katarzyna; Grabowski, Janusz
2016-03-01
Graded bundles are a class of graded manifolds which represent a natural generalisation of vector bundles and include the higher order tangent bundles as canonical examples. We present and study the concept of the linearisation of graded bundle which allows us to define the notion of the linear dual of a graded bundle. They are examples of double structures, graded-linear (GL) bundles, including double vector bundles as a particular case. On GL-bundles we define what we shall call weighted algebroids, which are to be understood as algebroids in the category of graded bundles. They can be considered as a geometrical framework for higher order Lagrangian mechanics. Canonical examples are reductions of higher tangent bundles of Lie groupoids. Weighted algebroids represent also a generalisation of VB-algebroids as defined by Gracia-Saz & Mehta and the LA-bundles of Mackenzie. The resulting structures are strikingly similar to Voronov's higher Lie algebroids, however our approach does not require the initial structures to be defined on supermanifolds.
Frobenius Pull Backs of Vector Bundles in Higher Dimensions
Indian Academy of Sciences (India)
V Trivedi
2012-11-01
We prove that for a smooth projective variety of arbitrary dimension and for a vector bundle over , the Harder–Narasimhan filtration of a Frobenius pull back of is a refinement of the Frobenius pull back of the Harder–Narasimhan filtration of , provided there is a lower bound on the characteristic (in terms of rank of and the slope of the destabilizing sheaf of the cotangent bundle of ). We also recall some examples, due to Raynaud and Monsky, to show that some lower bound on is necessary. We also give a bound on the instability degree of the Frobenius pull back of in terms of the instability degree of and well defined invariants of .
Radical power profile effect of DUPIC bundle on critical heat flux
International Nuclear Information System (INIS)
The axial and ring power profiles of DUPIC bundle are much different from those of reference 37-element fuel bundle since a DUPIC fuel bundle is -re-fabricated under proliferation resistance using spent PWR fuel and 2-bundle shift refuelling scheme of DUPIC bundle is proposed to CANDU-6 reactor. In case that the ring power porfile of a fuel bundle is altered, the flow and enthalpy distribution of subchannels and the radial position of CHF occurrence will be changed. Similarly, the axial power profile of a fuel channel affects CHF, axial position of CHF occurrence, axial enthalpy, quality and pressure distribution. The ring power profile of the DUPIC bundle as increasing burnup is much altered and flattened at high burnup, compared to 37-element bundle. It caused that one fuel bundle has a different ring power profile from the other fuel bundles at the different axial positions even in the same fuel channel. Therefore, how to consider burnup or ring power effect on CHF is very important to DUPIC thermalhydraulic analysis. At present study, thermalhydraulic analysis of a DUPIC bundles was performed in order to evaluate the ring power profile effect on CHF. The subchannel enthalpy, mass flux and CHF distribution from 0 burnup to discharged burnup (18,000 MWd/tHM) of DUPIC bundle were evaluated using ASSERT-PV subchannel code. The results of DUPIC bundles were compared to those of 37-elemental bundle and the comparability of DUPIC bundle with an existing CANDU-6 was presented in a CHF point of view
Nuclear spin relaxation due to random motion of vortex bundles
International Nuclear Information System (INIS)
The dependence of nuclear-spin-relaxation rate T1 on NMR resonant frequency for a layered superconducting sample has been analyzed theoretically. In the considered arrangement the Zeeman field has been applied in the plane of superconducting layers while the relaxation was due to interactions between the spin systems and moving flux bundles, created by the transport current flowing along superconducting layers. It has been found that the functional form of a dependence of spin-relaxation rate on the Zeeman field has two components, a Lorentzian and an oscillatory one. The characteristic rolloff frequency of the Lorentzian component depends on the pinning properties of the sample. The period of oscillations of the oscillatory component is of the order of the inverse of interaction time of flowing flux bundles with a probe nucleus. copyright 1996 The American Physical Society
Diffeological Clifford algebras and pseudo-bundles of Clifford modules
Pervova, Ekaterina
2015-01-01
We consider the diffeological version of the Clifford algebra of a (diffeological) finite-dimensional vector space; we start by commenting on the notion of a diffeological algebra (which is the expected analogue of the usual one) and that of a diffeological module (also an expected counterpart of the usual notion). After considering the natural diffeology of the Clifford algebra, and its expected properties, we turn to our main interest, which is constructing pseudo-bundles of diffeological C...
Integral Canonical Models for Automorphic Vector Bundles of Abelian Type
Lovering, Tom
2016-01-01
We define and construct integral canonical models for automorphic vector bundles over Shimura varieties of abelian type. More precisely, we first build on Kisin's work to construct integral canonical models over rings of integers of number fields with finitely many primes inverted for Shimura varieties of abelian type with hyperspecial level at all primes we do not invert, compatible with Kisin's construction. We then define a notion of an integral canonical model for the standard principal b...
Seismic analysis and test of model steam generator tube bundle
International Nuclear Information System (INIS)
The seismic response analysis and experimental study of a model PWR steam generator tube bundle has been completed. A planar tube mathematical model of linear FEM (finite element method) and simplified model tube bundle on the scale of 1:4.4 are used in the study. White noise sweep test shows that the effect of clearance and contact constraint between tube and anti-vibration bar is insignificant, the global fundamental frequency component is absolutely dominant, and the higher frequency components only affect the local vibration in different locations. The experimental results indicate that fundamental frequency component is dominant in seismic acceleration response spectrum. The second, third and fourth frequency components appear in the kind of frequency bands. The experimental data are in good agreement with the linear FEM results. The effectiveness of simplified mathematical model is verified
Multiplexed holographic memory by use of fiber bundle referencing
Zhang, Jiasen; Aruga, Tadashi
2005-04-01
We propose a volume holographic storage technique, in which a fiber bundle is used to guide the reference beam. Multiplexing is implemented by changing the incident direction of the laser beam upon the fiber bundle in the reference arm. In the technique, we make the system more compact by using a wedge prism to change the direction of the laser beam. This method has a large accessible angular scanning range and a large geometric storage bandwidth. Multiple images are stored in a LiNbO3:Fe crystal with an angular separation of 0.05° between successive holograms using a wedge prism with a deviation angle of 8°. This method is useful as a new image storage technique because of its compactness and simplicity.
CFD analysis of flow field in a triangular rod bundle
International Nuclear Information System (INIS)
The flow field was investigated in subchannels of VVER-440 pressurized water cooled reactors' fuel assemblies (triangular lattice, P/D = 1.35). Impacts of the mesh resolution and turbulence model were studied in order to obtain guidelines for CFD calculations of VVER-440 rod bundles. Results were compared to measurement data published by Trupp and Azad in 1975. The study pointed out that RANS method with BSL Reynolds stress model using a sufficient fine grid can provide an accurate prediction for the turbulence quantities in this lattice. Applying the experiences of the sensitivity study thermal hydraulic processes were investigated in VVER-440 rod bundle sections. Based on the examinations the spacer grids have important effects on the cross flows, axial velocity and outlet temperature distribution of subchannels therefore they have to be modeled satisfactorily in CFD calculations.
On phenomena of turbulent flow through rod bundles
International Nuclear Information System (INIS)
Experimental studies have shown that the axial and azimuthal turbulence intensities in the gap regions of rod bundles increase strongly with decreasing rod spacing; the fluctuating velocities in the axial and azimuthal directions have a quasi-periodic behavior. To determine the origin of this phenomenon and its characteristic as a function of the geometry and the Reynolds number, an experimental investigation was performed on the turbulent flow in several rod bundles with different aspect ratios (P/D, W/D). Hot-wires and microphones were used for the measurements of velocity and wall pressure fluctuations. The data were evaluated to obtain spectra as well as auto and cross correlations. Based on the results, a phenomenological model is proposed to explain this phenomenon. By means of the model, the mass exchange between neighbouring subchannels is explained. (orig.)
Lateral mechanical coupling of stereocilia in cochlear hair bundles.
Langer, M G; Fink, S.; Koitschev, A; Rexhausen, U; Hörber, J K; Ruppersberg, J P
2001-01-01
For understanding the gating process of transduction channels in the inner ear it is essential to characterize and examine the functional properties of the ultrastructure of stereociliary bundles. There is strong evidence that transduction channels in hair cells are gated by directly pulling at the so-called tip links. In addition to these tip links a second class of filamentous structures was identified in the scanning and transmission electron microscope: the side-to-side links. These links...
Universality Class of Fiber Bundle Model on Complex Networks
Kim, Dong-Hee; Kim, Beom Jun; Jeong, Hawoong
2004-01-01
We investigate the failure characteristics of complex networks within the framework of the fiber bundle model subject to the local load sharing rule in which the load of the broken fiber is transferred only to its neighbor fibers. Although the load sharing is strictly local, it is found that the critical behavior belongs to the universality class of the global load sharing where the load is transferred equally to all fibers in the system. From the numerical simulations and the analytical appr...
Infinitesimal moduli of G2 holonomy manifolds with instanton bundles
de la Ossa, Xenia; Svanes, Eirik Eik
2016-01-01
We describe the infinitesimal moduli space of pairs $(Y, V)$ where $Y$ is a manifold with $G_2$ holonomy, and $V$ is a vector bundle on $Y$ with an instanton connection. These structures arise in connection to the moduli space of heterotic string compactifications on compact and non-compact seven dimensional spaces, e.g. domain walls. Employing the canonical $G_2$ cohomology $H^*_{{\\check{\\rm d}}_E}(Y,E)$ developed by Reyes-Carri\\'on and Fern\\'andez and Ugarte, we show that the moduli space decomposes into the sum of the bundle moduli $H^1_{{\\check{\\rm d}}_A}(Y,{\\rm End}(V))$ plus the moduli of the $G_2$ structure preserving the instanton condition. The latter piece is contained in $H^1_{{\\check{\\rm d}}_\
CAT reconstruction and potting comparison of a LMFBR fuel bundle
International Nuclear Information System (INIS)
A standard Liquid Metal Fast Breeder Reactor (LMFBR) subassembly used in the Experimental Breeder Reactor II (EBR-II) was investigated, by remote techniques, for fuel bundle distortion by both nondestructive and destructive methods, and the results from both methods were compared. The non-destructive method employed neutron tomography to reconstruct the locations of fuel elements through the use of a maximum entropy reconstruction algorithm known as MENT. The destructive method consisted of ''potting'' (a technique that embeds and permanently fixes the fuel elements in a solid matrix) the subassembly, and then cutting and polishing the individual sections. The comparison indicated that the tomography reconstruction provided good results in describing the bundle geometry and spacer-wire locations, with the overall resolution being on the order of a spacer-wire diameter. A dimensional consistency check indicated that the element and spacer-wire dimensions were accurately reproduced in the reconstruction
Cellulosic Fibers: Effect of Processing on Fiber Bundle Strength
DEFF Research Database (Denmark)
Thygesen, Anders; Madsen, Bo; Thomsen, Anne Belinda; Lilholt, Hans
2011-01-01
A range of differently processed cellulosic fibers from flax and hemp plants were investigated to study the relation between processing of cellulosic fibers and fiber bundle strength. The studied processing methods are applied for yarn production and include retting, scutching, carding, and...... cottonization. There was a monotonically decreasing relationship between the strength and the number of processing steps, which was well fitted by an exponential regression line. The reduction factor was determined to be 0.27, indicating that the fiber bundle strength was on average reduced by 27% per...... processing step at the applied conditions. No large changes in cellulose content and crystallinity were observed, so the reduction in strength must be explained by other changes in the fiber ultrastructure. Altogether, the study presents a quantitative basis for reduction in strength of cellulosic fibers due...
Wrap groups of fiber bundles over quaternions and octonions
Ludkovsky, S. V.
2008-01-01
This article is devoted to the investigation of wrap groups of connected fiber bundles over the fields of real $\\bf R$, complex $\\bf C$ numbers, the quaternion skew field $\\bf H$ and the octonion algebra $\\bf O$. These groups are constructed with mild conditions on fibers. Their examples are given. It is shown, that these groups exist and for differentiable fibers have the infinite dimensional Lie groups structure, that is, they are continuous or differentiable manifolds and the composition $...
Darwin on the Treatment of Animals: His Thoughts Then and His Influence Now
Directory of Open Access Journals (Sweden)
Dr. Donna Yarri
2013-06-01
Full Text Available Charles Darwin’s theory of evolution has seriously challenged traditional religious views on the origins of life, as well as on our human-animal similarities. Darwin is often referenced in literature on animal ethics with regard to his contention that the difference between humans and other animals is one of degree rather than of kind. This paper posits that Darwin’s writings and theory make more positive contributions to the contemporary debate on animal ethics than for which he has previously been given credit. This paper addresses important aspects of Darwin’s theory for understanding our relationship with other animals and the implications for their subsequent treatment. First, this paper considers themes in Darwin’s original writings regarding relationships among different species; second, enhancements to his theory in support of these themes; and third, recommendations for how these themes can and should inform our moral reasoning and successive treatment of other animals.
Ab initio study of MoS2 nanotube bundles
Verstraete, Matthieu; Charlier, Jean-Christophe
2003-07-01
Recently, the synthesis of a new phase of MoS2I1/3 stoichiometry was reported [M. Remskar, A. Mrzel, Z. Skraba, A. Jesih, M. Ceh, J. Demšar, P. Stadelmann, F. Lévy, and D. Mihailovic, Science 292, 479 (2001)]. Electron microscope images and diffraction data were interpreted to indicate bundles of sub-nanometer-diameter single-wall MoS2 nanotubes. After experimental characterization, the structure was attributed to an assembly of “armchair” nanotubes with interstitial iodine. Using first-principles total-energy calculations, bundles of MoS2 nanotubes with different topologies and stoichiometries are investigated. All of the systems are strongly metallic. Configurations with “zigzag” structures are found to be more stable energetically than the “armchair” ones, though all of the structures have similar stabilities. After relaxation, there remain several candidates which give a lattice parameter in relative agreement with experiment. Further, spin-polarized calculations indicate that a structure with armchair tubes iodine atoms in their center acquires a very large spontaneous magnetic moment of 12μB, while the other structures are nonmagnetic. Our ab initio calculations show that in most of the other structures, the tubes are very strongly bound together, and that the compounds should be considered as a crystal, rather than as a bundle of tubes in the habitual sense.
The stages of atrioventricular bundle formation in the human embryonic heart
Directory of Open Access Journals (Sweden)
Silkina Yu.V.
2009-01-01
Full Text Available The origin, stages and histogenetic processes in atrioventricular bundle were investigated. We studied the human embryonic heart from 5 to 12 week of development. Antibodies to neurofilaments, Ki-67, MSA, α-SMA and neuregulin were used. Formation of the primordia of the atrioventricular bundle depends on the chamber formation in early heart. The first morphologic reconstruction in the atrioventricular bundle starts from 5 week of gestational age. In this time we studied proximal and distal primordias, which formed general tract at 7 week. The early human heart was characterized by strong connections with atrioventricular fibrous tissue, left and right septal cuspes of mitral and tricuspidal valves. Formation of the atrioventricular bundle branches has two stages: primary and repeated growth. Median fibers are blind-ended. We suppose that atrioventricular bundle and bundle branches have extracardiac origin. Histogenesis of the atrioventricular bundle contin-ues after 12 week of human development.
Bagger-Witten line bundles on moduli spaces of elliptic curves
Gu, W
2016-01-01
In this paper we discuss Bagger-Witten line bundles over moduli spaces of SCFTs. We review how in general they are `fractional' line bundles, not honest line bundles, twisted on triple overlaps. We discuss the special case of moduli spaces of elliptic curves in detail. There, the Bagger-Witten line bundles does not exist as an ordinary line bundle, but rather is necessarily fractional. As a fractional line bundle, it is nontrivial (though torsion) over the uncompactified moduli stack, and its restriction to the interior, excising corners with enhanced stabilizers, is also fractional. We review and compare to results of recent work arguing that well-definedness of the worldsheet metric implies that the Bagger-Witten line bundle is torsion, and give general arguments on the existence of universal structures on moduli spaces of SCFTs, in which superconformal deformation parameters are promoted to nondynamical fields ranging over the SCFT moduli space.
Improving the useful life of a 37-element fuel bundle
International Nuclear Information System (INIS)
Preliminary results indicate that CANDU burnup using 37-element fuel bundle with a slight enrichment can improve the useful life in the core. A slight enrichment in this study is increasing U-235 from 0.72 to 0.9 mass percent. A parametric study on criticality using Atomic Energy of Canada Limited’s WIMSAECL 3.1 and the Monte Carlo code, MCNP 5, developed by Los Alamos National Laboratory, is presented in this paper. (author)
The effects of fee bundling on dental utilization.
Porter, J.; Coyte, P. C.; Barnsley, J.; Croxford, R.
1999-01-01
OBJECTIVE: To examine dental utilization following an adjustment to the provincial fee schedule in which preventive maintenance (recall) services were bundled at lower fees. DATA SOURCES/STUDY SETTING: Blue Cross dental insurance claims for claimants associated with four major Ontario employers using a common insurance plan over the period 1987-1990. STUDY DESIGN: This before-and-after design analyzes the dental claims experience over a four-year period for 4,455 individuals 18 years of age a...
Separation and re-adhesion processes of two adhered single-walled carbon nanotube bundles
International Nuclear Information System (INIS)
Carbon nanotubes are desirable components of nanoelectromechanical (NEM) devices due to their excellent mechanical and electrical properties. In this study, dielectrophoresis, a potential high-rate nanomanufacturing process, was used to assemble single-walled carbon nanotube (SWCNT) bundles suspended over a trench. The intent was to assemble a single SWCNT bundle between two electrodes. However, it was observed that when two or more SWCNT bundles assembled across the trench, the bundles were attached together in a portion of the suspended section. This study models the separation and re-adhesion processes of two adhered SWCNT bundles as their internal tensions are varied using an atomic force microscope (AFM) tip. Two devices were selected with distinct SWCNT bundles. Observation of the force–distance measurements through applying an AFM tip at the middle of the suspended SWCNT bundles, in conjunction with continuum mechanics modelling, allowed the work of adhesion between the two nanotube bundles to be determined. As the force was applied by the AFM tip, the tension induced in each bundle increases sufficiently to partially overcome the adhesion between the bundles, thereby decreasing the adhesive length. The adhesive length then recovers due to the decrease in the induced tension during the unloading process. The average value of the work of adhesion between two adhered SWCNT bundles was determined to be 0.37 J m−2 according to the experimental data and modelling results. (paper)
Bundling in Telecommunications
Begoña García-Mariñoso; Xavier Martinez-Giralt; Pau Olivella
2008-01-01
The paper offers an overview of the literature on bundling in the telecommunications sector and its application in the Spanish market. We argue that the use of bundling in the provision of services is associated to technological reasons. Therefore, there appears no need to regulate bundling activities. However, this is not to say that other related telecom markets should not be scrutinized and regulated, or that the regulator should not pay attention to other bundling-related anticompetitive ...
Investigations on flow induced vibration of simulated CANDU fuel bundles in a pipe
International Nuclear Information System (INIS)
In this paper, vibration of a two-bundle string consisting of simulated CANDU fuel bundles subjected to turbulent liquid flow is investigated through numerical simulations and experiments. Large eddy simulation is used to solve the three-dimensional turbulent flow surrounding the fuel bundles for determining fluid excitations. The CFD model includes pipe flow, flow through the inlet fuel bundle along with its two endplates, half of the second bundle and its upstream endplate. The fluid excitation obtained from the fluid model is subsequently fed into a fuel bundle vibration code written in FORTRAN. Fluid structure interaction terms for the fuel elements are approximated using the slender body theory. Simulation results are compared to measurements conducted on the simulated fuel bundles in a testing hydraulic loop. (author)
Compactifications of the Heterotic string with unitary bundles
Energy Technology Data Exchange (ETDEWEB)
Weigand, T.
2006-05-23
In this thesis we investigate a large new class of four-dimensional supersymmetric string vacua defined as compactifications of the E{sub 8} x E{sub 8} and the SO(32) heterotic string on smooth Calabi-Yau threefolds with unitary gauge bundles and heterotic five-branes. The first part of the thesis discusses the implementation of this idea into the E{sub 8} x E{sub 8} heterotic string. After specifying a large class of group theoretic embeddings featuring unitary bundles, we analyse the effective four-dimensional N=1 supergravity upon compactification. From the gauge invariant Kaehler potential for the moduli fields we derive a modification of the Fayet-Iliopoulos D-terms arising at one-loop in string perturbation theory. From this we conjecture a one-loop deformation of the Hermitian Yang-Mills equation and introduce the idea of {lambda}-stability as the perturbatively correct stability concept generalising the notion of Mumford stability valid at tree-level. We then proceed to a definition of SO(32) heterotic vacua with unitary gauge bundles in the presence of heterotic five-branes and find agreement of the resulting spectrum with the S-dual framework of Type I/Type IIB orientifolds. A similar analysis of the effective four-dimensional supergravity is performed. Further evidence for the proposed one-loop correction to the stability condition is found by identifying the heterotic corrections as the S-dual of the perturbative part of {pi}-stability as the correct stability concept in Type IIB theory. After reviewing the construction of holomorphic stable vector bundles on elliptically fibered Calabi-Yau manifolds via spectral covers, we provide semi-realistic examples for SO(32) heterotic vacua with Pati-Salam and MSSM-like gauge sectors. We finally discuss the construction of realistic vacua with flipped SU(5) GUT and MSSM gauge group within the E{sub 8} x E{sub 8} framework, based on the embedding of line bundles into both E{sub 8} factors. Some of the appealing
Lateral mechanical coupling of stereocilia in cochlear hair bundles.
Langer, M G; Fink, S; Koitschev, A; Rexhausen, U; Hörber, J K; Ruppersberg, J P
2001-06-01
For understanding the gating process of transduction channels in the inner ear it is essential to characterize and examine the functional properties of the ultrastructure of stereociliary bundles. There is strong evidence that transduction channels in hair cells are gated by directly pulling at the so-called tip links. In addition to these tip links a second class of filamentous structures was identified in the scanning and transmission electron microscope: the side-to-side links. These links laterally connect stereocilia of the same row of a hair bundle. This study concentrates on mechanical coupling of stereocilia of the tallest row connected by side-to-side links. Atomic Force microscopy (AFM) was used to investigate hair bundles of outer hair cells (OHCs) from postnatal rats (day 4). Although hair bundles of postnatal rats are still immature at day 4 and interconnecting cross-links do not show preferential direction yet, hair bundles of investigated OHCs already showed the characteristic V-shape of mature hair cells. In a first experiment, the stiffness of stereocilia was investigated scanning individual stereocilia with an AFM tip. The spring constant for the excitatory direction was 2.5 +/- 0.6 x 10(-3) N/m whereas a higher spring constant (3.1 +/- 1.5 x 10(-3) N/m) was observed in the inhibitory direction. In a second set of experiments, the force transmission between stereocilia of the tallest row was measured using AFM in combination with a thin glass fiber. This fiber locally displaced a stereocilium while the force laterally transmitted to the neighboring untouched taller stereocilia was measured by AFM. The results show a weak force interaction between tallest stereocilia of postnatal rats. The force exerted to an individual stereocilium declines to 36% at the nearest adjacent stereocilium of the same row not touched with the fiber. It is suggested that the amount of force transmitted from a taller stereocilium to an adjacent one of the same row depends
Effect of Candu Fuel Bundle Modeling on Sever Accident Analysis
Energy Technology Data Exchange (ETDEWEB)
Dupleac, D.; Prisecaru, I. [Power Plant Engineering Faculty, Politehnica University, 313 Splaiul Independentei, 060042, sect. 6, Bucharest (Romania); Mladin, M. [Institute for Nuclear Research, Pitesti-Mioveni, 115400 (Romania)
2009-06-15
In a Candu 6 nuclear power reactor fuel bundles are located in horizontal Zircaloy pressure tubes through which the heavy-water coolant flows. Each pressure tube is surrounded by a concentric calandria tube. Outside the calandria tubes is the heavy-water moderator contained in the calandria itself. The moderator is maintained at a temperature of 70 deg. C by a separate cooling circuit. The moderator surrounding the calandria tubes provides a potential heat sink following a loss of core heat removal. The calandria vessel is in turn contained within a shield tank (or reactor vault), which provides biological shielding during normal operation and maintenance. It is a large concrete tank filled with ordinary water. During normal operation, about 0.4% of the core's thermal output is deposited in the shield tank and end shields, through heat transfer from the calandria structure and fission heating. In a severe accident scenario, the shield tank could provide an external calandria vessel cooling which can be maintained until the shield tank water level drops below the debris level. The Candu system design has specific features which are important to severe accidents progression and requires selective consideration of models, methods and techniques of severe accident evaluation. Moreover, it should be noted that the mechanistic models for severe accident in Candu system are largely less well validated and as the result the level of uncertainty remains high in many instances. Unlike the light water reactors, for which are several developed computer codes to analyze severe accidents, for Candu severe accidents analysis two codes were developed: MAAP4-Candu and ISAAC. However, both codes started by using MAAP4/PWR as reference code and implemented Candu 6 specific models. Thus, these two codes had many common features. Recently, a joint project involving Romanian nuclear organizations and coordinated by Politehnica University of Bucharest has been started. The purpose
Comparison of ASSERT subchannel code with Marviken bundle data
International Nuclear Information System (INIS)
In this paper ASSERT predictions are compared with the Marviken 6-rod bundle and 36+1 rod bundle. The predictions are presented for two experiments in the 6-rod bundle and four experiments in the 36+1 rod bundle. For low inlet subcooling, the void predictions are in good agreement with the experimental data. For high inlet subcooling, however, the agreement is not as good. This is attributed to the fact that in the high inlet subcooling experiments, single phase turbulent mixing plays a more important role in determining flow conditions in the bundle
The value of the abnormalities of bronchovascular bundles in the diagnosis of diffused lung diseases
International Nuclear Information System (INIS)
To evaluate the abnormalities of bronchovascular bundles in the differential diagnosis of the diffuse lung disease, seventy-two patients with diffuse lung diseases were evaluated, 15 of 72 patients were pathologically proven and the others clinically proven. Of these 72 patients, there were 33 patients with diffuse pulmonary interstitial disease, 5 patients with pulmonary parenchymal disease, 14 patients with bronchial disease, and 20 patients with disseminated disease. All patients had conventional CT scan of the chest, some also had HRCT scan. All CT images were jointly reviewed by two radiologists. The features of the abnormalities of bronchovascular bundles included: (1) Thinning of bronchovascular bundles, predominantly seen in diffuse interstitial disease of lung and chronic bronchitis; (2) thickening of bronchovascular bundles, predominantly seen in interstitial diseases and disseminated lung diseases such as sarcoidosis and lymphangitis carcinomatosis with beaded appearance of bronchovascular bundles; (3) Increased visibility of bronchovascular bundles, predominantly seen in bronchiolitis and disseminated lung diseases. CT features of the abnormalities of bronchovascular bundles are present in 80% of diffuse lung diseases. The features are not specific, but the beaded bronchovascular bundles are always seen in sarcoidosis and lymphangitis carcinomatosis. In making a distinction between idiopathic pulmonary fibrosis and chronic bronchitis complicated with interstitial fibrosis, the position of diaphragm is of value in differential diagnosis, normal or elevated diaphragm is usually seen in the former, while low and flattened diaphragm in the latter. Change of the appearance of bronchovascular bundles from normality to abnormality reflects the process of development of the lung disease
Darwin on the Treatment of Animals: His Thoughts Then and His Influence Now
Dr. Donna Yarri; Dr. Spencer S. Stober
2013-01-01
Charles Darwin’s theory of evolution has seriously challenged traditional religious views on the origins of life, as well as on our human-animal similarities. Darwin is often referenced in literature on animal ethics with regard to his contention that the difference between humans and other animals is one of degree rather than of kind. This paper posits that Darwin’s writings and theory make more positive contributions to the contemporary debate on animal ethics than for which he has previous...
Double-bundle depiction of the anterior cruciate ligament at 3 Tesla
International Nuclear Information System (INIS)
Magnetic resonance imaging on 3 Tesla (3T MRI) with arthroscopic correlation has proven to adequately identify the anteromedial bundle (AMB) and posterolateral bundle (PLB) in cadaver knees. The purpose of this study was to describe the depiction of ACL bundle anatomy on 3T MRI in daily practice. In a retrospective cohort study, we included 50 consecutive patients who underwent standard 3T MRI of the knee and had an intact ACL. Two musculoskeletal radiologists independently reviewed all scans for depiction of ACL bundle anatomy using standardized forms. Descriptive statistics were used. Twenty-three right knees (46%) and 27 left knees (54%) were included in the study. Mean age of the patients was 35 years (range 12 to 68 years); 37 patients were male (74%). ACL bundle anatomy was best depicted in the axial plane in 44 knees (88%) and in the coronal plane in six knees (12%). Two bundles were seen in 47 knees (94%). The AMB was completely seen in 45 knees (90%). The PLB was completely seen in 40 knees (80%). Both bundles were completely seen in 37 knees (76%). The double-bundle anatomy of the ACL is visualized in 94% of patients on 3T MRI. Because of potentially associated clinical benefits, we advocate to report separately on the anteromedial bundle and posterolateral bundle in case of anterior cruciate ligament injury of the knee. (orig.)
Double-bundle depiction of the anterior cruciate ligament at 3 Tesla
Energy Technology Data Exchange (ETDEWEB)
Adriaensen, M.E.A.P.M. [Atrium Medical Center Parkstad, Department of Radiology, Heerlen (Netherlands); Hogan, B. [Sports Surgery Clinic, Department of Radiology, Dublin (Ireland); Al-Bulushi, H.I.J. [Armed Forces Hospital, Department of Radiology, Muscat (Oman); Kavanagh, E.C. [Mater Misericordiae Hospital, Department of Radiology, Dublin (Ireland)
2012-07-15
Magnetic resonance imaging on 3 Tesla (3T MRI) with arthroscopic correlation has proven to adequately identify the anteromedial bundle (AMB) and posterolateral bundle (PLB) in cadaver knees. The purpose of this study was to describe the depiction of ACL bundle anatomy on 3T MRI in daily practice. In a retrospective cohort study, we included 50 consecutive patients who underwent standard 3T MRI of the knee and had an intact ACL. Two musculoskeletal radiologists independently reviewed all scans for depiction of ACL bundle anatomy using standardized forms. Descriptive statistics were used. Twenty-three right knees (46%) and 27 left knees (54%) were included in the study. Mean age of the patients was 35 years (range 12 to 68 years); 37 patients were male (74%). ACL bundle anatomy was best depicted in the axial plane in 44 knees (88%) and in the coronal plane in six knees (12%). Two bundles were seen in 47 knees (94%). The AMB was completely seen in 45 knees (90%). The PLB was completely seen in 40 knees (80%). Both bundles were completely seen in 37 knees (76%). The double-bundle anatomy of the ACL is visualized in 94% of patients on 3T MRI. Because of potentially associated clinical benefits, we advocate to report separately on the anteromedial bundle and posterolateral bundle in case of anterior cruciate ligament injury of the knee. (orig.)
On the permeability of fractal tube bundles
Zinovik, I
2011-01-01
The permeability of a porous medium is strongly affected by its local geometry and connectivity, the size distribution of the solid inclusions and the pores available for flow. Since direct measurements of the permeability are time consuming and require experiments that are not always possible, the reliable theoretical assessment of the permeability based on the medium structural characteristics alone is of importance. When the porosity approaches unity, the permeability-porosity relationships represented by the Kozeny-Carman equations and Archie's law predict that permeability tends to infinity and thus they yield unrealistic results if specific area of the porous media does not tend to zero. The goal of this paper is an evaluation of the relationships between porosity and permeability for a set of fractal models with porosity approaching unity and a finite permeability. It is shown that the two-dimensional foams generated by finite iterations of the corresponding geometric fractals can be used to model poro...
Signature modulo 8 of fibre bundles
Rovi, Carmen
2015-01-01
Lay summary Topology studies the geometric properties of spaces that are preserved by continuous deformations. Manifolds are the main examples of topological spaces, with the local properties of Euclidean space in an arbitrary dimension n. They are the higher dimensional analogs of curves and surfaces. For example a circle is a one-dimensional manifold. Balloons and doughnuts are examples of two-dimensional manifolds. A balloon cannot be deformed continuously into a doughnut...
Interconnection of bundled solid oxide fuel cells
Brown, Michael; Bessette, II, Norman F; Litka, Anthony F; Schmidt, Douglas S
2014-01-14
A system and method for electrically interconnecting a plurality of fuel cells to provide dense packing of the fuel cells. Each one of the plurality of fuel cells has a plurality of discrete electrical connection points along an outer surface. Electrical connections are made directly between the discrete electrical connection points of adjacent fuel cells so that the fuel cells can be packed more densely. Fuel cells have at least one outer electrode and at least one discrete interconnection to an inner electrode, wherein the outer electrode is one of a cathode and and anode and wherein the inner electrode is the other of the cathode and the anode. In tubular solid oxide fuel cells the discrete electrical connection points are spaced along the length of the fuel cell.
International Nuclear Information System (INIS)
To model thermal mechanical bundle deformation behaviour under high temperature conditions, several factors need to be considered. These are the sources of loads, deformation mechanisms, interactions within bundle components, bundle and pressure tube (PT) interaction, and boundary constraints on the fuel bundles under in-reactor conditions. This paper describes the modelling of the following three processes: Bundle slumping due to high temperature creep-sag of individual elements and endplates; Differential element expansion and fuel element bowing; and, Bundle distortion under axial loads. To model these processes, a number of key mechanisms for bundle deformation must be considered, which include: 1) Interaction of fuel elements in a bundle with their neighbours, 2) Endplate deformation, 3) Fuel elements lateral deformation under various loads and mechanisms, 4) Interaction within a fuel element, 5) Material property change at high temperatures, 6) Transient response of a bundle, and 7) Bundle configuration change. This paper summarises the new models needed for the mechanistic modelling of the key mechanisms mentioned above and provides an example to show how an endplate plasticity model is developed with results. (author)
Paul Dirac and the Pervasiveness of His Thinking
Olive, David I.
2003-01-01
I shall use a few personal reminiscences of my time as a student and colleague of Dirac in Cambridge to introduce some reflections on the nature of research in theoretical physics. I shall discuss and illustrate the approach of Dirac to his own research and the pervasiveness of the influence his example has provided. I shall discuss how ideas produced at all stages of his career have proved to be extraordinarily visionary, still motivating and exerting an influence on research many years afte...
Black-and-White Bundles of Joy
Institute of Scientific and Technical Information of China (English)
2007-01-01
Panda cubs pose with sponsors of the Wolong Giant Panda Protection and Research Center in southwest China’s Sichuan Province before they were moved outdoors in early February.The 18 weanling coddles, all about six months old, will live together in a garden at the Wolong center for half a year before they are separated. They will then be trained and selected for an experimental program designed to release captive-bredpandas to the wild. The Wolong center saw births of 19 panda cubs in 12 deliveries last year, with 17 survivals, a historical record. In addition, it saved and bred a cub delivered by a wild panda last August. Giant pandas, only found in China, are known as “living fossils” and about 1,590 still live in the wilds of Sichuan, Shaanxi and Gansu provinces.Currently, about 200 pandas are being bred in captivity worldwide, over half of which are living at the Wolong center.
Clifford Malcolm: Glimpses of His South African Legacy of Hope
Govender, Nadaraj; Ramsuran, Anitha; Dhunpath, Rubby
2008-01-01
This article reviews the contributions of Cliff Malcolm while in South Africa during the period 1997-2005. It focuses on his contribution to the fields of science education, teacher education, learner-centered education, transformational outcomes-based education and HIV/AIDS education. In this paper we provide snapshots of his work as an academic,…
Parameter design and optimization of tight-lattice rod bundles
International Nuclear Information System (INIS)
Thin rod bundles with tight lattice are arranged according to the equilateral triangle grid, as the proportion of fuel is large, and the power density of core is high. Based on the analysis of the performance of core, the ABV-6M reactor is taken as the example, and two objective functions, power density and flow rate of coolant are proposed for optimization calculation. Diameter and pitch of rod are optimized by using GA method respectively. The results, which are considered to be safety in security checking, show that tight lattice is effective for improving the power density and other performances of the reactor core. (author)
Hydrodynamic behavior of a bare rod bundle. [LMFBR
Energy Technology Data Exchange (ETDEWEB)
Bartzis, J.G.; Todreas, N.E.
1977-06-01
The temperature distribution within the rod bundle of a nuclear reactor is of major importance in nuclear reactor design. However temperature information presupposes knowledge of the hydrodynamic behavior of the coolant which is the most difficult part of the problem due to complexity of the turbulence phenomena. In the present work a 2-equation turbulence model--a strong candidate for analyzing actual three dimensional turbulent flows--has been used to predict fully developed flow of infinite bare rod bundle of various aspect ratios (P/D). The model has been modified to take into account anisotropic effects of eddy viscosity. Secondary flow calculations have been also performed although the model seems to be too rough to predict the secondary flow correctly. Heat transfer calculations have been performed to confirm the importance of anisotropic viscosity in temperature predictions. All numerical calculations for flow and heat have been performed by two computer codes based on the TEACH code. Experimental measurements of the distribution of axial velocity, turbulent axial velocity, turbulent kinetic energy and radial Reynolds stresses were performed in the developing and fully developed regions. A 2-channel Laser Doppler Anemometer working on the Reference mode with forward scattering was used to perform the measurements in a simulated interior subchannel of a triangular rod array with P/D = 1.124. Comparisons between the analytical results and the results of this experiment as well as other experimental data in rod bundle array available in literature are presented. The predictions are in good agreement with the results for the high Reynolds numbers.
The bundles of algebraic and Dirac-Hestenes spinor fields
International Nuclear Information System (INIS)
Our main objective in this paper is to clarify the ontology of Dirac-Hestenes spinor fields (DHSF) and its relationship with even multivector fields, on a Riemann-Cartan spacetime (RCST) M=(M,g,∇,τg,↑) admitting a spin structure, and to give a mathematically rigorous derivation of the so-called Dirac-Hestenes equation (DHE) in the case where M is a Lorentzian spacetime (the general case when M is a RCST will be discussed in another publication). To this aim we introduce the Clifford bundle of multivector fields (Cl(M,g)) and the left (ClSpin1,3el(M)) and right (ClSpin1,3er(M)) spin-Clifford bundles on the spin manifold (M,g). The relation between left ideal algebraic spinor fields (LIASF) and Dirac-Hestenes spinor fields (both fields are sections of ClSpin1,3el(M)) is clarified. We study in detail the theory of covariant derivatives of Clifford fields as well as that of left and right spin-Clifford fields. A consistent Dirac equation for a DHSF Ψ is a member of sec ClSpin1,3el(M) (denoted DECll) on a Lorentzian spacetime is found. We also obtain a representation of the DECll in the Clifford bundle Cl(M,g). It is such equation that we call the DHE and it is satisfied by Clifford fields ψΞ is a member of sec Cl(M,g). This means that to each DHSF Ψ is a member of sec ClSpin1,3el(M) and spin frame Ξ is a member of sec PSpin1,3e(M), there is a well-defined sum of even multivector fields ψΞ isa member of sec Cl(M,g) (EMFS) associated with Ψ. Such an EMFS is called a representative of the DHSF on the given spin frame. And, of course, such a EMFS (the representative of the DHSF) is not a spinor field. With this crucial distinction between a DHSF and its representatives on the Clifford bundle, we provide a consistent theory for the covariant derivatives of Clifford and spinor fields of all kinds. We emphasize that the DECll and the DHE, although related, are equations of different mathematical natures. We study also the local Lorentz invariance and the
On bundles of rank 3 computing Clifford indices
Lange, H
2012-01-01
Let $C$ be a smooth irreducible projective algebraic curve defined over the complex numbers. The notion of the Clifford index of $C$ was extended a few years ago to semistable bundles of any rank. Recent work has been focussed mainly on the rank-2 Clifford index, although interesting results have also been obtained for the case of rank 3. In this paper we extend this work, obtaining improved lower bounds for the rank-3 Clifford index. This allows the first computations of the rank-3 index in non-trivial cases and examples for which the rank-3 index is greater than the rank-2 index.
Heal, Geoffrey
2002-01-01
Biodiversity provides essential services to human societies. Many of these services are provided as public goods, so that they will typically be underprovided both by market mechanisms (because of the impossibility of excluding non-payers from using the services) and by government-run systems (because of the free rider problem). I suggest here that in some cases the public goods provided by biodiversity conservation can be bundled with private goods and their value to consumers captured in th...
Numerical simulation of turbulent flow in a rod bundle geometry
International Nuclear Information System (INIS)
This paper presents predictions of turbulent flows in a rod bundle geometry by using the k-ε turbulence model and the Reynolds stress model. Significant difference was not found in the predicted turbulence properties by the two models. The secondary flow predicted by the Reynolds stress model, which was nearly 1.2% of axial bulk velocity, changed the distribution of mean axial velocity, turbulence intensities and Reynolds shear stresses. The Reynolds stress model was unable to estimate the flow pulsation which is the main contribution of turbulent interchange mixing between subchannels. (author)
Quantum Bundle Description of the Quantum Projective Spaces
Buachalla, Réamonn Ó
2011-01-01
We realise Heckenberger and Kolb's canonical calculus on quantum projective (n-1)-space as the restriction of a distinguished quotient of the standard bicovariant calculus for Cq[SUn]. We introduce a calculus on the quantum (2n-1)-sphere in the same way. With respect to these choices of calculi, we present quantum projective (N-1)-space as the base space of two different quantum principal bundles, one with total space Cq[SUn], and the other with total space Cq[S^(2n-1)]. We go on to give Cq[C...
Visualization of the medial forebrain bundle using diffusion tensor imaging
Directory of Open Access Journals (Sweden)
Ardian Hana
2015-10-01
Full Text Available Diffusion tensor imaging is a technique that enables physicians the portrayal of white matter tracts in vivo. We used this technique in order to depict the medial forebrain bundle in 15 consecutive patients between 2012 and 2015. Men and women of all ages were included. There were 6 women and 9 men. The mean age was 58,6 years (39-77. Nine patients were candidates for an eventual deep brain stimulation. Eight of them suffered from Parkinson`s disease and one had multiple sclerosis. The remaining 6 patients suffered from different lesions which were situated in the frontal lobe. These were 2 metastasis, 2 meningiomas, 1 cerebral bleeding and 1 glioblastoma. We used a 3DT1-sequence for the navigation. Furthermore T2- and DTI- sequences were performed. The FOV was 200 x 200 mm², slice thickness 2 mm, and an acquisition matrix of 96 x 96 yielding nearly isotropic voxels of 2 x 2 x 2 mm. 3-Tesla-MRI was carried out strictly axial using 32 gradient directions and one b0-image. We used Echo-Planar-Imaging (EPI and ASSET parallel imaging with an acceleration factor of 2. b-value was 800 s/mm². The maximal angle was 50°. Additional scanning time was less than 9 minutes. We were able to visualize the medial forebrain bundle in 12 of our patients bilaterally and in the remaining 3 patients we depicted the medial forebrain bundle on one side. It was the contralateral side of the lesion. These were 2 meningiomas and one metastasis. Portrayal of the medial forebrain bundle is possible for everyday routine for neurosurgical interventions. As part of the reward circuitry it might be of substantial importance for neurosurgeons during deep brain stimulation in patients with psychiatric disorders. Furthermore it might explain at a certain extent character changes in patients with lesions in the frontal lobe. Surgery in this part of the brain should always take the preservation of this white matter tract into account.
Padilla-Gamiño, J. L.; Weatherby, T. M.; Waller, R. G.; Gates, R. D.
2011-06-01
The majority of scleractinian corals are hermaphrodites that broadcast spawn their gametes separately or packaged as egg-sperm bundles during spawning events that are timed to the lunar cycle. The egg-sperm bundle is an efficient way of transporting gametes to the ocean surface where fertilization takes place, while minimizing sperm dilution and maximizing the opportunity for gamete encounters during a spawning event. To date, there are few studies that focus on the formation and structure of egg-sperm bundle. This study explores formation, ultrastructure, and longevity of the egg-sperm bundle in Montipora capitata, a major reef building coral in Hawai`i. Our results show that the egg-sperm bundle is formed by a mucus layer secreted by the oocytes. The sperm package is located at the center of each bundle, possibly reflecting the development of male and female gametes in different mesenteries. Once the egg-sperm bundle has reached the ocean surface, it breaks open within 10-35 min, depending on the environmental conditions (i.e., wind, water turbulence). Although the bundle has an ephemeral life span, the formation of an egg-sperm bundle is a fundamental part of the reproductive process that could be strongly influenced by climate change and deterioration of water quality (due to anthropogenic effects) and thus requires further investigation.
Thermohydraulic tests of 3x3-rod bundle maquette
International Nuclear Information System (INIS)
The results of a 3x3-rod bundle thermohydraulic research program, performed in the Thermohydraulics Laboratory of NUCLEBRAS' Nuclear Technology Development Center, are briefly described. This program included measurements of pressure drops in one and two-phase flows, heat transfer coefficients, mixing between interconnected subchannels in one-phase flow conditions and critical heat fluxes. The measurements covered the following parameter ranges: heat fluxes from zero to the critical values, pressure ranging from 1 to 15 ata, inlet temperature from 25 to 150 sup(0)C and flow rate from 20 to 300l/min. (author)
Numerical simulation of flow-induced vibrations in tube bundles
International Nuclear Information System (INIS)
Full text of publication follows: In many industrial components mechanical structures like rod cluster control assembly, fuel assembly and heat exchanger tube bundles are submitted to complex flows causing possible vibrations and damage. Fluid forces are usually split into two parts: structure motion independent forces and fluid-elastic forces coupled with tube motion and responsible for possible dynamic instability development leading to possible short term failures through high amplitude vibrations. Most classical fluid force identification methods rely on structure response experimental measurements associated with convenient data processes. Owing to recent improvements in Computational Fluid Dynamics (C.F.D.), numerical fluid force identification is now practicable in the presence of industrial configurations. The present paper is devoted to numerical simulation of flow-induced vibrations of tube bundles submitted to single-phase cross flows by using C.F.D. codes. Direct Numerical Simulation (D.N.S.), Arbitrary Lagrange Euler formulation (A.L.E.) and code coupling process are involved to predict fluid forces responsible for tube bundle vibrations in the presence of fluid structure and fluid-elastic coupling effects. In the presence of strong multi-physics coupling, simulation of flow-induced vibrations requires a fluid structure code coupling process. The methodology consists in solving in the same time thermohydraulics and mechanics problems by using an A.L.E. formulation for the fluid computation. The purpose is to take into account coupling between flow and structure motions in order to be able to capture coupling effects. From a numerical point of view, there are three steps in the computation: the fluid problem is solved on the computational domain; fluid forces acting on the moving tube are estimated; finally they are introduced in the structure solver providing the tube displacement that is used to actualize the fluid computational domain. Specific
Foliation, jet bundle and quantization of Einstein gravity
Park, I Y
2015-01-01
With the Hamiltonian and Lagrangian analyses in the ADM setup, it was observed in \\cite{Park:2014tia} that the physical configuration space of the 4D Einstein-Hilbert action admits a three-dimensional description. Subsequently, a more mathematical picture of the reduction based on foliation theory was presented in \\cite{Park:2014qoa}. In this work, we expand \\cite{Park:2014qoa} by adding another mathematical ingredient - an element of jet bundle theory - and present a more systematic and refined account thereof.
Mohammadi, Morteza; Foroutan, Masumeh
2013-02-21
In this work, the two mixtures of ionic liquid 1-n-propyl-4-amino-1,2,4-triazolium bromide and each type of the aggregated single-walled carbon nanotubes (SWCNTs), i.e. bundled SWCNTs and non-bundled, were investigated using molecular dynamics (MD) simulations. The structural characteristics of a SWCNT in the ionic liquid (IL) were examined by analyzing the radial distribution functions and the results show that the nearest IL cations to the SWCNT surface can approach it from three different positions. Also, the possibility of the dispersion of the bundled SWCNTs containing three and seven carbon nanotubes was investigated. The obtained results showed that under the investigated conditions, the IL cannot disperse the bundled SWCNTs, but it can disperse six and seven aggregated non-bundled ones. Moreover, we investigated the underlying dispersion mechanism of the aggregated SWCNTs in the IL, using MD simulations. The self diffusion coefficients and transport numbers of the cations and anions were computed in the systems containing pure IL, the mixtures of IL and one, six and seven non-bundled SWCNTs and the systems containing IL and bundled SWCNTs with three and seven carbon nanotubes. The obtained results showed that the diffusion coefficients and the transport numbers of the cations are more than anions in all mentioned systems. PMID:23318467
Semistable vector bundles and Tannaka duality from a computational point of view
Kaid, Almar
2011-01-01
We develop a semistability algorithm for vector bundles which are given as a kernel of a surjective morphism between splitting bundles on the projective space over an algebraically closed field K. This class of bundles is a generalization of syzygy bundles. We show how to implement this algorithm in a computer algebra system. Further we give applications, mainly concerning the computation of Tannaka dual groups of stable vector bundles of degree 0 on the projective space and on certain smooth complete intersection curves. We also use our algorithm to close a gap in a recent work of L. Costa, P. Macias Marques and R. M. Miro-Roig regarding the stability of the syzygy bundle of general forms. Finally, we apply our algorithm to provide a computational approach to tight closure. All algorithms are implemented in the computer algebra system CoCoA
Study of O’Neill’s Tragic View in the Light of his Life Experience
Institute of Scientific and Technical Information of China (English)
杨宝珍; 杨巳炜
2013-01-01
O’Neill’s tragedy deeply rooted in his own life experience and his family heredity. He is an offspring of Irish immi-grants, his homelessness as a child, his early education in the catholic school and his later break with religion, his foreign expedi-tion, life on the sea and his three marriages all influenced his life and his career and his theme decisively.
Leo Kanner's Mention of 1938 in His Report on Autism Refers to His First Patient
Olmsted, Dan; Blaxill, Mark
2016-01-01
Leo Kanner begins his landmark 1943 case series on autistic children by stating the condition was first brought to his attention in 1938. Recent letters to "JADD" have described this reference as "mysterious" and speculated it refers to papers published that year by Despert or Asperger. In fact, as Kanner goes on to state, 1938…
Vadim Kuznetsov. Informal Biography by Eyes of His First Adviser
Directory of Open Access Journals (Sweden)
Igor V. Komarov
2007-06-01
Full Text Available The paper is dedicated to the memory of prominent theoretical physicist and mathematician Dr. Vadim Kuznetsov who worked, in particular, in the fields of the nonlinear dynamics, separation of variables, integrability theory, special functions. It includes his short research biography, an account of the start of his research career and the list of publications.
Studying the vibrations of rod bundles under asymmetrical flow-round
International Nuclear Information System (INIS)
The results of experimental invesigation into vibrations of peripheral tubes in a rod bundle initiated by coolant flow are presented. Conditions of flowing around the rod bundles with different deflections in the channel geometry and hydrodynamics of coolant flow are simulated on special models. Data characterizing the dependence of the rod vibration amplitudes on the value of the gap between the bundle and the channel as well as the effect of the transverse constituent of the coolant overflow from the centre of the bundle to periphery on the rod vibration amplitude in one- and two-phase flows are obtained
Review of Ordered Anarchy: Jasay and his Surroundings
Directory of Open Access Journals (Sweden)
Aschwin de Wolf
2009-02-01
Full Text Available Anthony de Jasay is among the most important social thinkers of our time. His oeuvre offers a sustained critique of government and its defenders. In the book Ordered Anarchy: Jasay and His Surroundings, colleagues and friends pay tribute to the man in the form of an inspiring collection of essays.
Tanner, J; Kiernan, M; Hilliam, R; Davey, S; Collins, E; Wood, T; Ball, J; Leaper, D
2016-04-01
Introduction In 2010 a care bundle was introduced by the Department of Health (DH) to reduce surgical site infections (SSIs) in England. To date, use of the care bundle has not been evaluated despite incorporating interventions with resource implications. The aim of this study was to evaluate the DH SSI care bundle in open colorectal surgery. Methods A prospective cohort design was used at two teaching hospitals in England. The baseline group consisted of 127 consecutive patients having colorectal surgery during a 6-month period while the intervention group comprised 166 patients in the subsequent 6 months. SSI and care bundle compliance data were collected using dedicated surveillance staff. Results Just under a quarter (24%) of the patients in the baseline group developed a SSI compared with just over a quarter (28%) in the care bundle group (p>0.05). However, compliance rates with individual interventions, both before and after the implementation of the bundle, were similar. Interestingly, in only 19% of cases was there compliance with the total care bundle. The single intervention that showed an associated reduction in SSI was preoperative warming (p=0.032). Conclusions The DH care bundle did not reduce SSIs after open colorectal surgery. Despite this, it is not possible to state that the bundle is ineffective as compliance rates before and after bundle implementation were similar. All studies evaluating the effectiveness of care bundles must include data for compliance with interventions both before and after implementation of the care bundle; poor compliance may be one of the reasons for the lower than expected reduction of SSIs. PMID:26924481
Application of artificial neural network in bundle critical heat flux prediction
International Nuclear Information System (INIS)
A bundle critical heat flux (CHF) database based on subchannel local condition is obtained by analyzing existing bundle experimental database with COBRA-IV code. Artificial neural network is then applied to train the database and a bundle CHF prediction model is finally obtained. The prediction accuracy of the obtained model is much better than that from general empiric formula, and the root-mean-square of predicated value is 5.63%. (authors)
Redesign and replacement of Connecticut Yankee moisture separator/reheater (MSR) tube bundles
International Nuclear Information System (INIS)
This paper describes the various aspects of the tube bundle redesign and replacement coordinated by Northeast Utilities Service Company for the Connecticut Yankee Atomic Power Company during the plant's 1980 refueling outage. The main objective of the replacement was to improve the operating reliability along with secondary plant chemistry through the use of new bundle design and tube material. The considerations leading to the selection of material and design of the new bundles, the highlights of fabrication and bundle change-out, and the eddy current test experience and performance monitoring techniques and results are presented. 6 refs
Guido of Arezzo and His Influence on Music Learning
Directory of Open Access Journals (Sweden)
Anna J. Reisenweaver
2012-05-01
Full Text Available Throughout the history of Western music, Guido of Arezzo stands out as one of the most influential theorists and pedagogues of the Middle Ages. His developments of the hexachord system, solmization syllables, and music notation revolutionized the teaching and learning of music during his time and laid the foundation for our modern system of music. While previous theorists were interested in the philosophical and mathematical nature of music, Guido’s desire to aid singers in the learning process was practical. Through his innovations, students were able to classify, sight-sing, and visualize the music they were learning, ultimately resulting in an easier, simpler, and more efficient way to learn music. By building upon the theories of those before him, Guido expanded and reshaped the musical system of his day, transformed the way music was taught, and established his ideas as a vital part of our musical heritage.
A Mathematical Base for Fibre Bundle Formulation of Lagrangian Quantum Field Theory
International Nuclear Information System (INIS)
The paper contains a differential-geometric foundations for an attempt to formulate Lagrangian (canonical) quantum field theory on fibre bundles. In it the standard Hilbert space of quantum field theory is replace with a Hilbert bundle; the former playing a role of a (typical) fibre of the letter one. Suitable sections of that bundle replace the ordinary state vectors and the operators on the system's Hilbert space are transformed into morphisms of the same bundle. In particular, the field operators are mapped into corresponding field morphisms.
Hydraulic reinforcement of channel at lower tie-plate in BWR fuel bundle
International Nuclear Information System (INIS)
This patent describes an apparatus in a fuel bundle for confining fuel rods for the generation of steam in a steam water mixture passing interior of the fuel bundle. The fuel bundle includes: a lower tie-plate for supporting the fuel rods and permitting flow from the lower exterior portion of the fuel bundle into the interior portion of the fuel bundle; a plurality of fuel rods. The fuel rods supported on the lower tie-plate extending upwardly to and towards the upper portion of the fuel bundle for the generation of steam in a passing steam and water mixture interior of the fuel bundle; an upper tie-plate for maintaining the fuel rods in side-by-side relation and permitting a threaded connection between a plurality of the fuel rods with the threaded connection being at the upper and lower tie-plate. The upper tie-plate permitting escape of a steam water mixture from the top of the fuel bundle; a fuel bundle channel; and a labyrinth seal configured in the lower tie-plate
Dislodgement of carbon nanotube bundles under pressure driven flow.
Baowan, Duangkamon; Cox, Barry J; Hill, James M
2010-04-16
Experimental and predicted flow rates through carbon nanotubes vary considerably but generally are reported to be well in excess of that predicted by the conventional Poiseuille flow, and therefore nanotubes embedded in a matrix might provide membranes with exceptional mass transport properties. In this paper, applied mathematical modelling is undertaken to estimate the three forces acting on a nanotube bundle, namely the molecular interaction force, the viscous force, and the static pressure force. In deducing estimates of these forces we introduce a modification of the notion of the effective dead area for a carbon nanotube membrane, and we calculate the total forces necessary to push one or more of the nanotubes out of the bundle, thus creating a channel through which further enhancement of flow may take place. However, careful analysis shows that the nett dislodgement force is entirely independent on the useable flow area, but rather depends only on the total cross-sectional area perpendicular to the flow. This rather surprising result is a consequence of the flow being steady and a balance of the viscous and pressure forces. PMID:20332554
An assessment of thermal behavior of the DUPIC fuel bundle by subchannel analysis
International Nuclear Information System (INIS)
Thermal behavior of the standard DUPIC fuel has been assessed. The DUPIC fuel bundle has been modeled for a subchannel analysis using the ASSERT-IV code which was developed by AECL. From the calculated mixture enthalpy, equilibrium quality and void fraction distributions of the DUPIC fuel bundle, it is found that net buoyancy effect is pronounced in the central region of the DUPIC fuel bundle when compared with the standard CANDU fuel bundle. It is also found that the central region of the DUPIC fuel bundle can be cooled more efficiently than that of the standard fuel bundle. Based upon the subchannel modeling used in this study, the location of minimum CHFR in the DUPIC fuel bundle has been found to be very similar to that of the standard fuel. From the calculated mixture enthalpy distribution at the exit of the fuel channel, it is found that the mixture enthalpy and void fraction can be highest in the peripheral region of the DUPIC fuel bundle. On the other hand, the enthalpy and the void fraction was found to be highest in the central region of the standard CANDU fuel bundle at the exit of the fuel channel. Since the transverse interchange model between subchannels is important for the behavior of these variables, it is needed to put more effort in validating the transverse interchange model. For the purpose of investigating influence of thermal-hydraulic parameter variations of the DUPIC fuel bundle, four different values of the channel flow rates were used in the subchannel analysis. The effect of the channel flow reduction on thermal-hydraulic parameters have been presented. This study shows that the subchannel analysis is very useful in assessing thermal behavior of the fuel bundles in CANDU reactors. (author). 12 refs., 3 tabs., 17 figs
The Abilities of a Musical Savant and His Family.
Young, R. L.; Nettelbeck, T.
1995-01-01
Evaluation of a 12-year-old autistic musical savant revealed that the boy had idiosyncratic levels of cognitive functioning and perfect pitch recognition. His ability to recall and perform musical pieces after listening to a tape recording were found to be exceptional, but dependent upon his familiarity with musical structure and therefore…
Post-irradiation examination of the 37M fuel bundle at Chalk River Laboratories (AECL)
Energy Technology Data Exchange (ETDEWEB)
Armstrong, J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Daniels, T. [Ontario Power Generation, Pickering, Ontario (Canada); Montin, J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)
2014-03-15
The modified (-element (37M) fuel bundle was designed by Ontario Power Generation (OPG) to improve Critical Heat Flux (CHF) performance in ageing pressure tubes. A modification of the conventional 37-element fuel bundle design, the 37M fuel bundle allows more coolant flow through the interior sub-channels by way of a smaller central element. A demonstration irradiation (DI) of thirty-two fuel bundles was completed in 2011 at OPG's Darlington Nuclear Generating Station to confirm the suitability of the 37M fuel bundles for full core implementation. In support of the DI, fuel elements were examined in the Chalk River Laboratories Hot Cells. Inspection activities included: Bundle and element visual examination; Bundle and element dimensional measurements; Verification of bundle and element integrity; and Internal Gas Volume Measurements. The inspection results for 37M were comparable to that of conventional 37-element CANDU fuel. Fuel performance parameters of the 37M DI fuel bundle and fuel elements were within the range observed for similarly operated conventional 37-element CANDU fuel. Based on these Post Irradiation Examination (PIE) results, 37M fuel performed satisfactorily. (author)
Numerical model for thermal and mechanical behaviour of a CANDU 37-element bundle
International Nuclear Information System (INIS)
Prediction of transient fuel bundle deformations is important for assessing the integrity of fuel and the surrounding structural components under different operating conditions including accidents. For numerical simulation of the interactions between fuel bundle and pressure tube, a reliable numerical bundle model is required to predict thermal and mechanical behaviour of the fuel bundle assembly under different thermal loading conditions. To ensure realistic representations of the bundle behaviour, this model must include all of the important thermal and mechanical features of the fuel bundle, such as temperature-dependent material properties, thermal viscoplastic deformation in sheath, fuel-to-sheath interactions, endplate constraints and contacts between fuel elements. In this paper, we present a finite element based numerical model for predicting macroscopic transient thermal-mechanical behaviour of a complete 37-element CANDU nuclear fuel bundle under accident conditions and demonstrate its potential for being used to investigate fuel bundle to pressure tube interaction in future nuclear safety analyses. This bundle model has been validated against available experimental and numerical solutions and applied to various simulations involving steady-state and transient loading conditions. (author)
Development of an advanced LMR steam generator free from SWR with a double tube bundle configuration
International Nuclear Information System (INIS)
This paper describes the activities made at KAERI to develop an advanced LMR(Liquid Metal Reactor) steam generator which is free from SWR (Sodium Water Reaction) to resolve the concern of the SWR possibility and improve the economic feature of an LMR. The steam generator design houses two tube bundles that are functionally different and its tube bundle zone is radially or vertically divided into two regions. The SG is equipped with hot and cold fluid tube bundles, medium fluid and a pump. It prevents the occurrence of a sodium water reaction while sodium is still being used as the coolant for the primary heat transport system. The feasibility of using the SG with a double tube bundle for an actual use in a LMR plant is evaluated by setting up the skeleton of the NSSS for various possible configurations of the SG tube bundles. Analysis was made for various types of the new steam generator with a double tube bundle. Since the heat transfer in the SG is made among the three different fluids, it comes to have its unique heat transfer characteristics. The analysis showed the possibility for the occurrence of an undesirable reversed heat transfer not only in the integrated single-region bundle type but also in the integrated double-region bundle type. The performance analysis revealed practical performance characteristics for the various bundle configurations. Also the feasibility study for the various NSSS configurations with the new SG is described. (authors)
Overview of methods to increase dryout power in CANDU fuel bundles
Energy Technology Data Exchange (ETDEWEB)
Groeneveld, D.C., E-mail: degroeneveld@gmail.com [Chalk River Laboratories, AECL, Chalk River (Canada); University of Ottawa, Department of Mechanical Engineering, Ottawa (Canada); Leung, L.K.H. [Chalk River Laboratories, AECL, Chalk River (Canada); Park, J.H. [Korean Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2015-06-15
Highlights: • Small changes in bundle geometry can have noticeable effects on the bundle CHF. • Rod spacing devices can results in increases of over 200% in CHF. • CHF enhancement decays exponentially downstream from spacers. • CHF-enhancing bundle appendages also increase the post-CHF heat transfer. - Abstract: In CANDU reactors some degradation in the CCP (critical channel power, or power corresponding to the first occurrence of CHF in any fuel channel) will occur with time because of ageing effects such as pressure-tube diametral creep, increase in reactor inlet-header temperature, increased hydraulic resistance of feeders. To compensate for the ageing effects, various options for recovering the loss in CCP are described in this paper. They include: (i) increasing the bundle heated perimeter, (ii) optimizing the bundle configuration, (iii) optimizing core flow and flux distribution, (iv) reducing the bundle hydraulic resistance, (v) use of CHF-enhancing bundle appendages, (vi) more precise experimentation, and (vii) redefining CHF. The increase in CHF power has been quantified based on experiments on full-scale bundles and subchannel code predictions. The application of several of these CHF enhancement principles has been used in the development of the 43-rod CANFLEX bundle.
Mixed connectivity of Cartesian graph products and bundles
Erves, Rija
2010-01-01
Mixed connectivity is a generalization of vertex and edge connectivity. A graph is $(p,0)$-connected, $p>0$, if the graph remains connected after removal of any $p-1$ vertices. A graph is $(p,q)$-connected, $p\\geq 0$, $q>0$, if it remains connected after removal of any $p$ vertices and any $q-1$ edges. Cartesian graph bundles are graphs that generalize both covering graphs and Cartesian graph products. It is shown that if graph $F$ is $(p_{F},q_{F})$-connected and graph $B$ is $(p_{B},q_{B})$-connected, then Cartesian graph bundle $G$ with fibre $F$ over the base graph $B$ is $(p_{F}+p_{B},q_{F}+q_{B})$-connected. Furthermore, if $q_{F},q_{B}>0$, then $G$ is also $(p_{F}+p_{B}+1,q_{F}+q_{B}-1)$-connected. Finally, let graphs $G_i, i=1,...,n,$ be $(p_i,q_i)$-connected and let $k$ be the number of graphs with $q_i>0$. The Cartesian graph product $G=G_1\\Box G_2\\Box ... \\Box G_n$ is $(\\sum p_i,\\sum q_i)$-connected, and, for $ k\\geq 1$, it is also $(\\sum p_i+k-1,\\sum q_i-k+1)$-connected.
Enhanced metalloadsorption of bacterial cells displaying poly-His peptides
Energy Technology Data Exchange (ETDEWEB)
Sousa, C.; Cebolla, A.; Lorenzo, V. de [CSIC, Madrid (Spain)
1996-08-01
The properties of Escherichia coli cells, acquired by cell surface presentation of one or two hexahistidine (His) clusters carried by the outer membrane LamB protein, have been examined. Strains producing LamB hybrids with the His chains accumulated greater than 11-fold more Cd{sup 2} than E. coli cells expressing the protein without the His insert. Furthermore, the hexa-His chains on the cell surface caused cells to adhere reversibly to a Ni{sup 2+}-containing solid matrix in a metal-dependent fashion. Thus, expression of poly-His peptides enables bacteria to act as a metalloaffinity adsorbent. These results open up the possibility for biosorption of heavy ions using engineered microorganisms. 32 refs., 3 figs.
The electrochemical properties of bundles of single-walled nanotubes
Energy Technology Data Exchange (ETDEWEB)
Zawodzinski, T.A. Jr.; Haridoss, P.; Uribe, F.A.
1998-12-31
This is the final report of a Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The authors studied electrochemical properties of single-walled fullerene nanotube bundles. The materials exhibited a highly anisotropic conductivity. Electrochemical cycling in solutions of alkyl ammonium salts in propylene carbonate revealed that the nanotubes are stable to at least {+-}1.5 V and have a fairly high accessible surface area. Double-layer charging currents of approximately 30 farads per gram were observed. This is on the same order of magnitude, though somewhat lower, than state-of-the-art values for ultra-capacitor materials. Electrochemical insertion of lithium was attempted. Though several features were observed in a slow cyclic voltammetric scan, these features were not reversible, indicating little reversible insertion. Several possible reasons for this behavior are discussed.
Subtleties Concerning Conformal Tractor Bundles
Graham, C Robin
2012-01-01
The realization of tractor bundles as associated bundles in conformal geometry is studied. It is shown that different natural choices of principal bundle with normal Cartan connection corresponding to a given conformal manifold can give rise to topologically distinct associated tractor bundles for the same inducing representation. Consequences for homogeneous models and conformal holonomy are described. A careful presentation is made of background material concerning standard tractor bundles and equivalence between parabolic geometries and underlying structures.
Harmonic sections of Riemannian vector bundles, and metrics of Cheeger-Gromoll type
Benyounes, M.; Loubeau, E.; Wood, C.M., Bucking, C., Fitzpatrick, J., & Nadella, S.R.
2006-01-01
We study harmonic sections of a Riemannian vector bundle whose total space is equipped with a 2-parameter family of metrics which includes both the Sasaki and Cheeger-Gromoll metrics. This enables the theory of harmonic unit sections to be extended to bundles with non-zero Euler class.
Peter Delpeut and His "Cinema of Loss"
Gilaitis, Aleksas, 1987-
2013-01-01
The era of television pushed film towards a slow death that has become more apparent in today's visual culture. Private collections of cinema rarely uphold any footage in the same form as it was invented more than one-hundred years ago. The problem of changing archival formats has led many films to complete disappearance since archival politics cannot protect every single image created by every single visual artist in the world. Early cinema has went through another “death“ of cinema with cru...
Manager of Educational Project and His Competencies
Directory of Open Access Journals (Sweden)
Katerina Hrazdilova Bockova
2013-11-01
Full Text Available It is more than desirable for project-oriented activities to be conducted and managed by people with relevant knowledge and experience. At the same time, managers should have appropriate skills in order to apply knowledge and experience respectably in the context of the study field and the situation. The aim of this presented paper is to propose a competency model of educational projects which shall be primary used in the educational institutions. The contribution consists of two parts. The first part is focused on the basic terminology issues and anchor concepts such as competencies and the competency model. The second part is dedicated to the description of the specific proposal for a precise competency model and its subsequent presentation and verification.
Strategies for the Evaluation of HIS Vendors
Rothenberg, Joan R.; Goodman, John D.
1984-01-01
The keys to successful hospital information system acquisition are discussed. Topics addressed include setting hospital objectives, documenting system requirements, identifying suitable vendors, preparing requests for information and proposals, and evaluating systems and vendors. The benefits of proper planning are stressed.
Boltanski's moral sociology and his implicit theory of ideology
Jacquemain, Marc
2008-01-01
The paper exposes the main lines of sociology of action regimes and of justification of Boltanski. It also shows how his concept of "test" is very well suited to a non deterministic sociology, a sociology of contingency
International Nuclear Information System (INIS)
The nondimensional parameters of fluid-elastic vibration of tube bundle were derived and the effective method for vibration countermeasure of damage of tube bundle in the cross flow was investigated. It was explained that an application to the fluid-elastic vibration of cross-shaped tube bundle in the lower plenum structure of the future BWR reactor developed. Three nondimensional parameters such as mass attenuation parameter, nondimensional flow velocity and Reynolds number controlled the limiting flow velocity generating fluid-elastic vibrations of tube bundle in cross flow. The effect of mass attenuation parameter to the nondimensional limiting flow velocity is small when the value is smaller than 1. The effect of Reynolds number may be small when the exfoliation point does not change. It was thought two effective countermeasures of fluid-elastic vibrations: 1) the bundle tubes were tied up in a bundle not to vibrate with phase difference among tubes and 2) the real limiting flow velocity was increased at the same nondimensional limiting flow velocity by increasing the eigenfrequency. (S.Y.)
Myron Mathisson: What Little we Know of his Life
International Nuclear Information System (INIS)
Myron Mathisson (1897-1940) was a Polish Jew known for his work on the equations of motion of bodies in general relativity and for developing a new method to analyze the properties of fundamental solutions of linear hyperbolic differential equations. In particular, he derived the equations for a spinning body moving in a gravitational field and proved, in a special case, the Hadamard conjecture on the class of equations that satisfy the Huygens principle. His work still exerts influence on current research. Drawing on various archival and secondary sources, in particular his correspondence with Einstein, we outline Mathisson's biography and scientific career. (author)
Cohomology of line bundles on the flag variety for type G_2
DEFF Research Database (Denmark)
Andersen, Henning Haahr; Kaneda, Masaharu
2012-01-01
In the case of a simple algebraic group G of type G2 over a field of characteristic p>0 we study the cohomology modules of line bundles on the flag variety for G. Our main result is a complete determination of the vanishing behavior of such cohomology in the case where the line bundles in question...
Extensions of Lie-Rinehart algebras and cotangent bundle reduction
Huebschmann, Johannes
2008-01-01
Let Q be a smooth manifold acted upon smoothly by a Lie group G, and let N be the space of G-orbits. The G-action lifts to an action on the total space T of the cotangent bundle of Q and hence on the ordinary symplectic Poisson algebra of smooth functions on T, and the Poisson algebra of G-invariant functions on T yields a Poisson structure on the space T/G of G-orbits. We develop a description of this Poisson structure in terms of the orbit space N and suitable additional data. When the G-action on Q is principal, the problem admits a simple solution in terms of extensions of Lie-Rinehart algebras. In the general case, extensions of Lie-Rinehart algebras do not suffice, and we show how the requisite supplementary information can be recovered from invariant theory.
Cortes, Viviana
2013-01-01
This article presents a group of lexical bundles identified in a corpus of research article introductions as the first step in the analysis of these expressions in the different sections of the research article. A one-million word corpus of research article introductions from various disciplines was compiled and the lexical bundles identified in…
MENT reconstruction and potting comparison of a LMFBR fuel bundle
International Nuclear Information System (INIS)
Since the advent of computer-assisted-tomography (CAT), the CAT techniques have been rapidly expanded to the nuclear industry. A number of investigators have applied these techniques to reconstruct the fuel bundle configuration inside a subassembly with various degrees of resolution; however, there has been little data available on the accuracy of these reconstructions, and no comparisons have been made with the internal structure of actual irradiated subassemblies. Some efforts have utilized pretest mock-ups to calibrate the CAT algorithms, but the resulting mock-up configurations do not necessarily represent an actual subassembly, so an exact comparison has been lacking. The purpose of this paper is to present the results of a comparison between a CAT reconstruction of an irradiated subassembly and the destructive examination of the same subassembly
Ion-irradiation-induced defects in bundles of carbon nanotubes
Salonen, E; Nordlund, K
2002-01-01
We study the structure and formation yields of atomic-scale defects produced by low-dose Ar ion irradiation in bundles of single-wall carbon nanotubes. For this, we employ empirical potential molecular dynamics and simulate ion impact events over an energy range of 100-1000 eV. We show that the most common defects produced at all energies are vacancies on nanotube walls, which at low temperatures are metastable but long-lived defects. We further calculate the spatial distribution of the defects, which proved to be highly non-uniform. We also show that ion irradiation gives rise to the formations of inter-tube covalent bonds mediated by carbon recoils and nanotube lattice distortions due to dangling bond saturation. The number of inter-tube links, as well as the overall damage, linearly grows with the energy of incident ions.
Collisionless magnetic reconnection associated with coalescence of flux bundles
International Nuclear Information System (INIS)
The basic process of collisionless reconnection is studied in terms of coalescence of magnetized flux bundles using an implicit particle simulation of two-dimensions. The toroidal electric field that directly relates to magnetic reconnection is generated solenoidally in a region much broader than the current sheet whose width is a few electron skin depths. The reconnected flux increases linearly in time, but it is insensitive to finite Larmor radii of the ions in this Sweet-Parker regime. The toroidal electric field is controlled by a balance of transit acceleration of finite-mass electrons and their removal by sub-Alfvenic E x B drift outflow. The simulation results supports the collisionless Ohm's law Et≅ηeqJt with ηeq the inertia resistivity. (author)
Fabrication of PWR fuel assembly and CANDU fuel bundle
International Nuclear Information System (INIS)
For the project of localization of nuclear fuel fabrication, the R and D to establish the fabrication technology of CANDU fuel bundle as well as PWR fuel assembly was carried out. The suitable boss height and the prober Beryllium coating thickness to get good brazing condition of appendage were studied in the fabrication process of CANDU fuel rod. Basic Studies on CANLUB coating method also were performed. Problems in each fabrication process step and process flow between steps were reviewed and modified. The welding conditions for top and bottom nozzles, guide tube, seal and thimble screw pin were established in the fabrication processes of PWR fuel assembly. Additionally, some researches for a part of PWR grid brazing problems are also carried out
CERN visit of His Excellency Mr.Kinga Singye / Bhutan
Hoch, Michael
2016-01-01
CERN visit of His Excellency Mr Kinga Singye Ambassador Extraordinary and Plenipotentiary Permanent Representative of the Kingdom of Bhutan to the United Nations Office and other international organisations in Geneva
Guido of Arezzo and His Influence on Music Learning
Anna J. Reisenweaver
2012-01-01
Throughout the history of Western music, Guido of Arezzo stands out as one of the most influential theorists and pedagogues of the Middle Ages. His developments of the hexachord system, solmization syllables, and music notation revolutionized the teaching and learning of music during his time and laid the foundation for our modern system of music. While previous theorists were interested in the philosophical and mathematical nature of music, Guido’s desire to aid singers in the learning proce...
Fracture process of a fiber bundle with strong disorder
Danku, Zsuzsa; Kun, Ferenc
2016-07-01
We investigate the effect of the amount of disorder on the fracture process of heterogeneous materials in the framework of a fiber bundle model. The limit of high disorder is realized by introducing a power law distribution of fiber strength over an infinite range. We show that on decreasing the amount of disorder by controlling the exponent of the power law the system undergoes a transition from the quasi-brittle phase where fracture proceeds in bursts to the phase of perfectly brittle failure where the first fiber breaking triggers a catastrophic collapse. For equal load sharing in the quasi-brittle phase the fat tailed disorder distribution gives rise to a homogeneous fracture process where the sequence of breaking bursts does not show any acceleration as the load increases quasi-statically. The size of bursts is power law distributed with an exponent smaller than the usual mean field exponent of fiber bundles. We demonstrate by means of analytical and numerical calculations that the quasi-brittle to brittle transition is analogous to continuous phase transitions and determine the corresponding critical exponents. When the load sharing is localized to nearest neighbor intact fibers the overall characteristics of the failure process prove to be the same, however, with different critical exponents. We show that in the limit of the highest disorder considered the spatial structure of damage is identical with site percolation—however, approaching the critical point of perfect brittleness spatial correlations play an increasing role, which results in a different cluster structure of failed elements.
Load sharing in the growth of bundled biopolymers
International Nuclear Information System (INIS)
To elucidate the nature of load sharing in the growth of multiple biopolymers, we perform stochastic simulations of the growth of biopolymer bundles against obstacles under a broad range of conditions and varying assumptions. The obstacle motion due to thermal fluctuations is treated explicitly. We assume the ‘perfect Brownian ratchet’ model, in which the polymerization rate equals the free-filament rate as soon as the filament-obstacle distance exceeds the monomer size. Accurate closed-form formulas are obtained for the case of a rapidly moving obstacle. We find the following: (1) load sharing is usually sub-perfect in the sense that polymerization is slower than for a single filament carrying the same average force; (2) the sub-perfect behavior becomes significant at a total force proportional to the logarithm or the square root of the number of filaments, depending on the alignment of the filaments; (3) for the special case of slow barrier diffusion and low opposing force, an enhanced obstacle velocity for an increasing number of filaments is possible; (4) the obstacle velocity is very sensitive to the alignment of the filaments in the bundle, with a staggered alignment being an order of magnitude faster than an unstaggered one at forces of only 0.5 pN per filament for 20 filaments; (5) for large numbers of filaments, the power is maximized at a force well below 1 pN per filament; (6) for intermediate values of the obstacle diffusion coefficient, the shape of the force velocity relation is very similar to that for rapid obstacle diffusion. (paper)
Modification of the Simpson moduli space M_{3m+1}(P_2) by vector bundles (I)
Iena, Oleksandr
2010-01-01
We consider the moduli space of stable vector bundles on curves embedded in P_2 with Hilbert polynomial 3m+1 and construct a compactification of this space by vector bundles. The result is a blow up of the Simpson moduli space M_{3m+1}(P_2).
Subchannel analysis of CANDU 37-element fuel bundles
International Nuclear Information System (INIS)
The subchannel analysis codes COBRA-IV and ASSERT-4 have been used to predict the mass and enthalpy imbalance within a CANDU 37-element fuel channel under various system conditions. The objective of this study was to assess the various capabilities of the ASSERT code and highlight areas where further validation or development may be needed. The investigation indicated that the ASSERT code has all the basic models required to accurately predict the flow and enthalpy imbalance for complex rod bundles. The study also showed that the code modelling of void drift and diffusion requires refinement to some coefficients and that further validation is needed at high flow rate and high void fraction conditions, where ASSERT and COBRA are shown to predict significantly different trends. The results of a recent refinement of ASSERT modelling are also discussed
Defects in crystalline packings of twisted filament bundles. II. Dislocations and grain boundaries.
Azadi, Amir; Grason, Gregory M
2012-03-01
Twisted and ropelike assemblies of filamentous molecules are common and vital structural elements in cells and tissues of living organisms. We study the intrinsic frustration occurring in these materials between the two-dimensional organization of filaments in cross section and out-of-plane interfilament twist in bundles. Using nonlinear continuum elasticity theory of columnar materials, we study the favorable coupling of twist-induced stresses to the presence of edge dislocations in the lattice packing of bundles, which leads to a restructuring of the ground-state order of these materials at intermediate twist. The stability of dislocations increases as both the degree of twist and lateral bundle size grow. We show that in ground states of large bundles, multiple dislocations pile up into linear arrays, radial grain boundaries, whose number and length grows with bundle twist, giving rise to a rich class of "polycrystalline" packings. PMID:22587105
Relationships between the Tensile Properties and Tenacity extension Behaviour of Fibre-bundles
Institute of Scientific and Technical Information of China (English)
YU Wei-dong
2002-01-01
Fibre bundle testing is different from single-fibre measurement, not only in testing methods and instruments, but in the results obtained. For wool fibres, Sirolan-TENSOR can supply fibre-bundle tenacity (BS) and bundle extension (BE), but has some limitations on the analysis of the measured tensile curves of fibre bundles. It has not only raised new parameters,such as initial modulus (BM) and specific work of rupture (BW), as well as the specific work before or after the peak-point(WBP or WAP) and the ratios of WAP/WBP and WAP/BW, but also compared the tensile behaviour of different fibre-bundles, e.g. wool,polyester and viscose rayon fibre- bundles. The experimental results from 32 lots of wool tops show that there are correlations between bundle tensile properties,such as BS-BE, BS-BM, BS-BW, BE-BW and BM-BW.However, the variables of coefficients of variance (CV)are almost independent of each other and have no correlation with the average values of fibre bundle tensile parameters, except for BS-CVBM and CVBM-BW.
Flow-induced vibration of steam generator tube bundles
International Nuclear Information System (INIS)
The vibrations induced in tube arrays by a transversal flow are of great practical interest because of their destructive effects especially on heat exchangers. Instabilities can appear beyond a critical flow velocity and induce very high vibratory levels which may involve fractures. These instabilities involve a fluidelastic coupling between the vibratory movement of the tubes and the flow round them. Studies are being carried out in France concerning steam generators. A lot of bundle mock-ups with various pitches have been tested and large range parameter domains have been investigated. In a second part, the C.E.A., FRAMATOME, E.D.F. and WESTINGHOUSE research program, which is being carried out, is presented
Structural evaluation of a DTHR bundle divertor particle collector
International Nuclear Information System (INIS)
The purpose of this report is to present a structural evaluation of the current bundle divertor particle collector BDPC design under a peak heat flux in relation to criteria that protect against coolant leakage into the plasma over replacement schedules planned during DTHR operation. In addition, an assessment of the BDPC structural integrity at higher heat fluxes is presented. Further, recommendations for modifications in the current BDPC design that would improve design reliability to be considered in future design studies are described. Finally, experimental test programs directed to establishing materials data necessary in providing greater confidence in subsequent structural evaluations of BDPC designs in relation to coolant leakage over planned replacement schedules are identified
Demonstrating the compatibility of Canflex fuel bundles with a CANDU 6 fuelling machine
International Nuclear Information System (INIS)
CANFLEX is a new 43-element fuel bundle, designed for high operating margins. It has many small-diameter elements in its two outer rings, and large-diameter elements in its centre rings. By this means, the linear heat ratings are lower than those of standard 37-element bundles for similar power outputs. A necessary part of the out-reactor qualification program for the CANFLEX fuel bundle design, is a demonstration of the bundle's compatibility with the mechanical components in a CANDU 6 Fuelling Machine (FM) under typical conditions of pressure, flow and temperature. The diameter of the CANFLEX bundle is the same as that of a 37-element bundle, but the smaller-diameter elements in the outer ring result in a slightly larger end-plate diameter. Therefore, to minimize any risk of unanticipated damage to the CANDU 6 FM sidestops, a series of measurements and static laboratory tests were undertaken prior to the fuelling machine tests. The tests and measurements showed that; a) the CANFLEX bundle end plate is compatible with the FM sidestops, b) all the dimensions of the CANFLEX fuel bundle are within the specified limits. (author). 3 tabs., 3 figs
Overview of flowline bundle technology from concept selection to offshore installation
Institute of Scientific and Technical Information of China (English)
Song Ruxin; Xia Qiuling
2013-01-01
Flowline bundle system consisting of carrier pipe,sleeve pipe and internal flowlines offers innovative solution for the infield transportation of oil and gas.Due to its features,flowline bundle offers a couple of advantages over conventional flowline in particular for cases where multi-flowlines and high thermal performance is of great interest.The main benefits and advantages of such system include excellent thermal performance to prevent wax formation and hydrates,multiple bundled flowlines,mechanical and corrosion protection,potential reuse,etc.With the developments of offshore oil and gas industries,more and more hydrocarbon resources are being explored and discovered from shallow to deep water.Pipeline bundle system can be a smart solution for certain applications,which can be safe and cost effective solution.The objective of this paper is to overview pipeline bundle technology,outline detailed engineering design issue and procedure.Focus is given to its potential application in offshore for infield transportation.Engineering design principles and procedures for pipeline bundle system are highlighted.Construction methods of flowline bundle onshore are reviewed.Offshore towing and installation of pipeline bundle procedure is outlined.
GPU acceleration of the stochastic grid bundling method for early-exercise options
Leitao Rodriguez, A.; Oosterlee, C.W.
2015-01-01
In this work, a parallel graphics processing units (GPU) version of the Monte Carlo stochastic grid bundling method (SGBM) for pricing multi-dimensional early-exercise options is presented. To extend the method’s applicability, the problem dimensions and the number of bundles will be increased drast
A Variant of K-Theory and Topological T-Duality for Real Circle Bundles
Gomi, Kiyonori
2015-03-01
For a space with involutive action, there is a variant of K-theory. Motivated by T-duality in type II orbifold string theory, we establish that a twisted version of the variant enjoys a topological T-duality for Real circle bundles, i.e., circle bundles with real structure.
Pliny the Elder and his History of Ancient Art
Directory of Open Access Journals (Sweden)
Graziella Melina
2007-12-01
Although Pliny the Elder based his history of ancient art on all the authors mentioned above, the writings of classical philologists and archeologists often imply that he might not have always used the art history literature mentioned as primary sources, but rather cited a great deal of information from the works of his predecessor, the famous Roman encyclopedist Marcus Terentius Varro (beginning of the 1st century BC.
Asymmetric dynamics of ion channel forming proteins - Hepatitis C virus (HCV) p7 bundles.
Kalita, Monoj Mon; Fischer, Wolfgang B
2016-07-01
Protein p7 of hepatitis C virus (HCV) is a short 63 amino acid membrane protein which homo-oligomerises in the lipid membrane to form ion and proton conducting bundles. Two different genotypes (GTs) of p7, 1a and 5a, are used to simulate hexameric bundles of the protein embedded in a fully hydrated lipid bilayer during 400ns molecular dynamics (MD) simulations. Whilst the bundle of GT 1a is based on a fully computational derived structure, the bundle of GT 5a is based on NMR spectroscopic data. Results of a full correlation analysis (FCA) reveal that albeit structural differences both bundles screen local minima during the simulation. The collective motion of the protein domains is asymmetric. No 'breathing-mode'-like dynamics is observed. The presence of divalent ions, such as Ca-ions affects the dynamics of especially solvent exposed parts of the protein, but leaves the asymmetric domain motion unaffected. PMID:27079148
Nicholas Economides
2014-01-01
We discuss strategic ways that sellers can use tying and bundling with requirement conditions to extract consumer surplus. We analyze different types of tying and bundling creating (i) intra-product price discrimination; (ii) intra-consumer price discrimination; and (iii) inter-product price discrimination, and assess the antitrust liability that these practices may entail. We also discuss the impact on consumers and competition, as well as potential antitrust liability of bundling “incontest...
Cobra-TF simulation of BWR bundle dry out experiments
International Nuclear Information System (INIS)
The COBRA-TF computer code uses a two-fluid, three-field and three-dimensional formulation to model a two-phase flow field in a specific geometry. The liquid phase is divided in a continuous liquid field and a separate dispersed field, which is used to describe the entrained liquid drops. For each space dimension, the code solves three momentum equations, three mass conservation equations and two energy conservation equations. Entrainment and depositions models are implemented into the code to model the mass transfer between the two liquid fields. This study presents the results obtained with COBRA-TF for the simulation of the Siemens 9-9Q BWR Bundle Dryout experiments. The model includes 20 channels and 34 axial nodes in the heated section. The predicted critical power and dryout location is compared with the measured values. An assessment of the code entrainment and de-entrainment models is presented. (authors)
Treatment, packaging, and storage of bundle scrap hardware
International Nuclear Information System (INIS)
A study was performed to identify and evaluate the various technical options for treatment, packaging and storing the bundle scrap hardware that results from rod consolidation. The three general scenarios addressed were keeping the treated scrap in the pool, moving it to on-site dry storage, or immediate disposal. The study concluded that practical alternatives existed for all three cases. Use of novel scrap packaging techniques achieved an overall net consolidation ratio of two. The most economical concept was found to be using advanced technology in the pool storage scenario with dry storage schemes a close second. The project also provides information on scrap characterization and provides tools to assist in classifying the scrap hardware
Gabriel Garcia Marquez; The Significant Message of His Literary Discourse
Directory of Open Access Journals (Sweden)
Mohammad B. Aghaei
2015-03-01
Full Text Available Gabriel Garcia Marquez’s literary discourse actually portrays the destructive domination of colonial and imperialistic powers and civil wars that led to a series of insecurities and poverty in the community. In fact, whatever he has presented in his works is related to the realities of the continent that have been portrayed in his fictional world. In his works, every single line is a reference to a certain critical point in the history of Latin American continent and provides a magnifying glass for the reader to clearly conceptualize them. His works also represent the contemporary events that are frequently happening in the society.Keywords: Latin America, figurative techniques, legacy of colonialism, violence, Liberal and Conservative parties
Photoacoustic imaging by using a bundle of thin hollow-optical fibers
Seki, A.; Iwai, K.; Katagiri, T.; Matsuura, Y.
2016-03-01
We propose a photoacoustic imaging system composed of a flexible bundle of thin hollow-optical fibers that enables endoscopic diagnosis. The hollow-fiber bundle involves 37 fibers with an inner diameter of 100 μm and the total diameter of the bundle is 1.2 mm. A laser beam for photoacoustic excitation is scanned at the input end of fiber bundle and therefore, no scanning mechanism is necessary at the distal end. In addition, owing to the small numerical aperture of hollow optical fibers, a high resolution image is obtained without using a micro-lens array at the end. By using the fiber bundle probe, photoacoustic imaging of blood vessels in the ovarian membrane of fish were successfully obtained with a laser fluence of around 2.8 mJ/cm2.
Characteristics of liquid and boiling sodium flows in heating pin bundles
International Nuclear Information System (INIS)
This study is related to cooling accidents which could occur in sodium cooled fast reactors. Thermo-hydraulic aspects of boiling experiments in pin bundles with helical wire-wrap spacer systems, in the case of undamaged geometries, are analyzed. Differences and analogies in the behavior of multi-rod bundle flows and one-dimensional channel flows are studied. A boiling model is developed for bundle geometries, and predictions obtained with the FLICA code using this models are presented. These predictions are compared with experimental results obtained in a water 19-rod bundle. Then, results of sodium boiling experiments through a 19-rod bundle are interpreted. Both cases of high power and reduced power are envisaged
Loop-Corrected Compactifications of the Heterotic String with Line Bundles
Blumenhagen, R; Weigand, T; Blumenhagen, Ralph; Honecker, Gabriele; Weigand, Timo
2005-01-01
We consider the E8 x E8 heterotic string theory compactified on Calabi-Yau manifolds with bundles containing abelian factors in their structure group. Generic low energy consequences such as the generalised Green-Schwarz mechanism for the multiple anomalous abelian gauge groups are studied. We also compute the holomorphic gauge couplings and induced Fayet-Iliopoulos terms up to one-loop order, where the latter are interpreted as stringy one-loop corrections to the Donaldson-Uhlenbeck-Yau condition. Such models generically have frozen combinations of Kaehler and dilaton moduli. We study concrete bundles with structure group SU(N) x U(1)^M yielding quasi-realistic gauge groups with chiral matter given by certain bundle cohomology classes. We also provide a number of explicit tadpole free examples of bundles defined by exact sequences of sums of line bundles over complete intersection Calabi-Yau spaces. This includes one example with precisely the Standard Model gauge symmetry.
Kim, Taekyung; Kim, Gunn; Choi, Woon Ih; Kwon, Young-Kyun; Zuo, Jian-Min
2010-01-01
We report a combined electronic transport and structural characterization study of small carbon nanotube bundles in field-effect transistors (FET). The atomic structures of the bundles are determined by electron diffraction using an observation window built in the FET. The single-walled nanotube bundles exhibit electrical transport characteristics sensitively dependent on the structure of individual tubes, their arrangements in the bundle, deformation due to intertube interaction, and the ori...
Coenzyme- and His-tag-induced crystallization of octopine dehydrogenase
International Nuclear Information System (INIS)
The crystal structure of octopine dehydrogenase revealed a specific role of the His5 tag in inducing the crystal contacts required for successful crystallization. Over the last decade, protein purification has become more efficient and standardized through the introduction of affinity tags. The choice and position of the tag, however, can directly influence the process of protein crystallization. Octopine dehydrogenase (OcDH) without a His tag and tagged protein constructs such as OcDH-His5 and OcDH-LEHis6 have been investigated for their crystallizability. Only OcDH-His5 yielded crystals; however, they were multiple. To improve crystal quality, the cofactor NADH was added, resulting in single crystals that were suitable for structure determination. As shown by the structure, the His5 tag protrudes into the cleft between the NADH and l-arginine-binding domains and is mainly fixed in place by water molecules. The protein is thereby stabilized to such an extent that the formation of crystal contacts can proceed. Together with NADH, the His5 tag obviously locks the enzyme into a specific conformation which induces crystal growth
Molecular mechanism of bundle formation by the bacterial actin ParM
Energy Technology Data Exchange (ETDEWEB)
Popp, David, E-mail: dpopp@imcb.a-star.edu.sg [ERATO ' Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673 Singapore (Singapore); Narita, Akihiro [ERATO ' Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Nagoya University Graduate School of Science, Structural Biology Research Center and Division of Biological Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Iwasa, Mitsusada [ERATO ' Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Maeda, Yuichiro [ERATO ' Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Nagoya University Graduate School of Science, Structural Biology Research Center and Division of Biological Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Robinson, Robert C. [Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673 Singapore (Singapore)
2010-01-22
The actin homolog ParM plays a microtubule-like role in segregating DNA prior to bacterial cell division. Fluorescence and cryo-electron microscopy have shown that ParM forms filament bundles between separating DNA plasmids in vivo. Given the lack of ParM bundling proteins it remains unknown how ParM bundles form at the molecular level. Here we show using time-lapse TIRF microscopy, under in vitro molecular crowding conditions, that ParM-bundle formation consists of two distinct phases. At the onset of polymerization bundle thickness and shape are determined in the form of nuclei of short helically disordered filaments arranged in a liquid-like lattice. These nuclei then undergo an elongation phase whereby they rapidly increase in length. At steady state, ParM bundles fuse into one single large aggregate. This behavior had been predicted by theory but has not been observed for any other cytomotive biopolymer, including F-actin. We employed electron micrographs of ParM rafts, which are 2-D analogs of 3-D bundles, to identify the main molecular interfilament contacts within these suprastructures. The interface between filaments is similar for both parallel and anti-parallel orientations and the distribution of filament polarity is random within a bundle. We suggest that the interfilament interactions are not due to the interactions of specific residues but rather to long-range, counter ion mediated, electrostatic attractive forces. A randomly oriented bundle ensures that the assembly is rigid and that DNA may be captured with equal efficiency at both ends of the bundle via the ParR binding protein.
The Packing of Flexible Screws and the Self-Limited Assembly of Biopolymer Bundles
Grason, Gregory
2009-03-01
Living cells rely heavily on assemblies of filamentous proteins, such as F-actin and microtubules, to perform a variety of tasks, ranging from adhesion and locomotion to cell division and intracellular transport. In the dynamic cellular environment, the efficiency of these tasks is crucially dependent on the robust assembly and disassembly of rope-like bundles of filamentous molecules. Recent in vitro studies of F-actin assembly [Lai et al., Phys. Rev. Lett. (2007)] suggest that bundle formation may take place as an equilibrium process, with a thermodynamically-preferred bundle diameter. Within the context of a generalized elastic model of filament packings, we explore the possibility that limited-bundle growth is directly linked with the intrinsic chiral structure of biological filaments themselves. The hexagonal packing of biopolymers leads to the build up of chiral stress, or torque, that generically induces the formation of twisting filament bundles of finite size. We demonstrate that the underlying elasticity of the bundle--i.e. whether hexagonal-solid or hexagonal-columnar--plays a key role in dictating both the thermodynamics (i.e. disperse, bundled or bulk aggregation) and structure (i.e. size and twist) of ``self-braiding" aggregates of helical filaments.
Institute of Scientific and Technical Information of China (English)
YU Wei-dong; Ron Postle; YANG Shou-ren; YAN Hao-jing
2002-01-01
The testing conditions of a fibre bundle tensile tester (TENSOR) are elongation speed (ES), gauge length (GL), pretension, jaw pressure, environmental temperature and relative humidity, instrument linearity and sensitivity. The effects on fibre-bundle tensile properties at different GL and ES have been discussed in detail and compared with Peirce's theories on the weaklinks and the breaking time effect. The experimental results indicate that the tensile properties of fibre bundles are strongly affected by GL and vary with different GL. The reasonable GL should be 5-15mm rather than 3.2mm for wool bundle measurements. The ES ranging from 20mm/min to 40mm/min is beneficial for obtaining comparatively stable and accurate tensile values, whereas 20 mm/min used in current testing for wool fibre bundles is at the lower limit of the suggested range. For bundle modulus measurement, the sampling interval must be selected appropriately. The new calculation of the sampling interval has been established.
Principal -bundles on Nodal Curves
Indian Academy of Sciences (India)
Usha N Bhosle
2001-08-01
Let be a connected semisimple affine algebraic group defined over . We study the relation between stable, semistable -bundles on a nodal curve and representations of the fundamental group of . This study is done by extending the notion of (generalized) parabolic vector bundles to principal -bundles on the desingularization of and using the correspondence between them and principal -bundles on . We give an isomorphism of the stack of generalized parabolic bundles on with a quotient stack associated to loop groups. We show that if is simple and simply connected then the Picard group of the stack of principal -bundles on is isomorphic to ⊕ , being the number of components of .
Methodology of study of the boiling crisis in a nuclear fuel rod bundle
International Nuclear Information System (INIS)
The boiling crisis is one of the phenomena limiting the available power from a nuclear power plant. It has been widely studied for decades, and numerous data, models, correlations or tables are now available in the literature. If we now try to obtain a general view of previous work in this field, we may note that there are several ways of tackling the subject. The mechanistic models try to modelize the two-phase flow topology and the interaction between different sublayers, and must be validated by comparison with basic experiments, such as DEBORA, where we try to get some detailed informations on the two-phase flow pattern in a pure and simple geometry. This allows us to obtain a better knowledge of the so-called 'intrinsic effect'. Up to now, these models are not yet acceptable for a nuclear use. As the geometry of the rod bundles and grids has a tremendous importance for the actual Critical Heat Flux (CHF), it is compulsory to have more precise results for a given fuel rod bundle in a restricted range of parameter: this leads to the empirical approach, using empirical CHF predictors (tables, correlations, splines, ...). One of the key points of such a method is the obtention of the local thermohydraulic values, that is to say the evaluation of the so-called 'mixing effect'. This is done by a subchannel analysis code or equivalent, which can be qualified on two kinds of experiments: overall flow measurements in a subchannel, such as HYDROMEL in single-phase flow or GRAZIELLA in two-phase flow, or detailed measurements inside a subchannel, such as AGATE. Nevertheless, the final qualification of a specific nuclear fuel, i.e. the synthesis of these mechanistic and empirical approaches, intrinsic and mixing effects, ..., must be achieved on a global test such as OMEGA. This is the strategy used in France by CEA and his partners FRAMATOME and EdF. (author)
Results of international standard problem No. 36 severe fuel damage experiment of a VVER fuel bundle
International Nuclear Information System (INIS)
International Standard Problems (ISP) organized by the OECD are defined as comparative exercises in which predictions with different computer codes for a given physical problem are compared with each other and with a carefully controlled experimental study. The main goal of ISP is to increase confidence in the validity and accuracy of analytical tools used in assessing the safety of nuclear installations. In addition, it enables the code user to gain experience and to improve his competence. This paper presents the results and assessment of ISP No. 36, which deals with the early core degradation phase during an unmitigated severe LWR accident in a Russian type VVER. Representatives of 17 organizations participated in the ISP using the codes ATHLET-CD, ICARE2, KESS-III, MELCOR, SCDAP/RELAP5 and RAPTA. Some participants performed several calculations with different codes. As experimental basis the severe fuel damage experiment CORA-W2 was selected. The main phenomena investigated are thermal behavior of fuel rods, onset of temperature escalation, material behavior and hydrogen generation. In general, the calculations give the right tendency of the experimental results for the thermal behavior, the hydrogen generation and, partly, for the material behavior. However, some calculations deviate in important quantities - e.g. some material behavior data - showing remarkable discrepancies between each other and from the experiments. The temperature history of the bundle up to the beginning of significant oxidation was calculated quite well. Deviations seem to be related to the overall heat balance. Since the material behavior of the bundle is to a great extent influenced by the cladding failure criteria a more realistic cladding failure model should be developed at least for the detailed, mechanistic codes. Regarding the material behavior and flow blockage some models for the material interaction as well as for relocation and refreezing requires further improvement
Results of international standard problem No. 36 severe fuel damage experiment of a VVER fuel bundle
Energy Technology Data Exchange (ETDEWEB)
Firnhaber, M. [Gesellschaft fuer Anlagen-und Reaktorsicherheit, Koeln (Germany); Yegorova, L. [Nuclear Safety Institute of Russian Research Center, Moscow (Russian Federation); Brockmeier, U. [Ruhr-Univ. of Bochum (Germany)] [and others
1995-09-01
International Standard Problems (ISP) organized by the OECD are defined as comparative exercises in which predictions with different computer codes for a given physical problem are compared with each other and with a carefully controlled experimental study. The main goal of ISP is to increase confidence in the validity and accuracy of analytical tools used in assessing the safety of nuclear installations. In addition, it enables the code user to gain experience and to improve his competence. This paper presents the results and assessment of ISP No. 36, which deals with the early core degradation phase during an unmitigated severe LWR accident in a Russian type VVER. Representatives of 17 organizations participated in the ISP using the codes ATHLET-CD, ICARE2, KESS-III, MELCOR, SCDAP/RELAP5 and RAPTA. Some participants performed several calculations with different codes. As experimental basis the severe fuel damage experiment CORA-W2 was selected. The main phenomena investigated are thermal behavior of fuel rods, onset of temperature escalation, material behavior and hydrogen generation. In general, the calculations give the right tendency of the experimental results for the thermal behavior, the hydrogen generation and, partly, for the material behavior. However, some calculations deviate in important quantities - e.g. some material behavior data - showing remarkable discrepancies between each other and from the experiments. The temperature history of the bundle up to the beginning of significant oxidation was calculated quite well. Deviations seem to be related to the overall heat balance. Since the material behavior of the bundle is to a great extent influenced by the cladding failure criteria a more realistic cladding failure model should be developed at least for the detailed, mechanistic codes. Regarding the material behavior and flow blockage some models for the material interaction as well as for relocation and refreezing requires further improvement.
International Nuclear Information System (INIS)
When CANDU reactor has defective fuel bundle during its operation, then the defective fuel bundle should be discharged by 2(two) fuel bundles at a time from the corresponding fuel channel until the failed fuel bundle is found. Existing fuel failure detection system GFP(Gaseous Fission Product) & DN(Delayed Neutron) Monitoring System can’t exactly distinguish fuel elements failure from each fuel bundle. Because of fuelling machine mechanism and discharge procedure, always two fuel bundles at a time are being inspected. In case visual inspection is available for inspecting fuel elements and suppose that there are no defects and damaged marks on the surface of outer fuel elements, 2(two) defective fuel bundles should be canned and kept in the separate region of spent fuel storage pool. Therefore, the purpose of this study was to develop a system which is capable of inspecting whether each fuel bundle is failed or not. KNF (KEPCO Nuclear Fuel Co. Ltd) developed two evaluation systems to investigate the integrity of CANDU spent fuel bundle. The first one is a sipping system that detects fission gases leaked from fuel element. The second one is a visual inspection system with radiation resistant underwater camera and remotely controlled devices. The sipping technology enables to analyze the leakage of fission products not only in gaseous state but also liquid state. The performance of developed systems was successfully demonstrated at Wolsong power plant this year. This paper describes the results of the development of the failed fuel detection technology and its application. (author)
Experimental analysis of redistribution of the transversal crossflow in rod bundles
International Nuclear Information System (INIS)
Fuel elements for PWR type nuclear reactors consist of rod bundles, in a square array and are held by grids. The coolant flows, mainly, axially along the rods. The inlet flow bad distribution can yield a strong crossflow. The present work consists in the experimental analysis of the transversal crossflow between 2 bundles with 4x4 rods each, with and without the presence of spacer-type grids, for several inlet flow conditions. It was observed that the crossflow is strongly dependent of the static pressure difference between the bundles and that the presence of grids induces a rapid homogenization of the flow. (C.M.)
Optical design of endoscopic shape-tracker using quantum dots embedded in fiber bundles
Eisenstein, Jessica; Gavalis, Robb; Wong, Peter Y.; Cao, Caroline G. L.
2009-08-01
Colonoscopy is the current gold standard for colon cancer screening and diagnosis. However, the near-blind navigation process employed during colonoscopy results in endoscopist disorientation and scope looping, leading to missed detection of tumors, incorrect localization, and pain for the patient. A fiber optic bend sensor, which would fit into the working channel of a colonoscope, is developed to aid navigation through the colon during colonoscopy. The bend sensor is comprised of a bundle of seven fibers doped with quantum dots (QDs). Each fiber within the bundle contains a unique region made up of three zones with differently-colored QDs, spaced 120° apart circumferentially on the fiber. During bending at the QD region, light lost from the fiber's core is coupled into one of the QD zones, inducing fluorescence of the corresponding color whose intensity is proportional to the degree of bending. A complementary metal oxide semiconductor camera is used to obtain an image of the fluorescing end faces of the fiber bundle. The location of the fiber within the bundle, the color of fluorescence, and the fluorescence intensity are used to determine the bundle's bending location, direction, and degree of curvature, respectively. Preliminary results obtained using a single fiber with three QD zones and a seven-fiber bundle containing one active fiber with two QDs (180° apart) demonstrate the feasibility of the concept. Further developments on fiber orientation during bundling and the design of a graphical user interface to communicate bending information are also discussed.
Kepler's theory of force and his medical sources.
Regier, Jonathan
2014-01-01
Johannes Kepler (1571-1630) makes extensive use of souls and spiritus in his natural philosophy. Recent studies have highlighted their importance in his accounts of celestial generation and astrology. In this study, I would like to address two pressing issues. The first is Kepler's context. The biological side of his natural philosophy is not naively Aristotelian. Instead, he is up to date with contemporary discussions in medically flavored natural philosophy. I will examine his relationship to Melanchthon's anatomical-theological Liber de anima (1552) and to Jean Femel's very popular Physiologia (1567), two Galenic sources with a noticeable impact on how he understands the functions of life. The other issue that will direct my article is force at a distance. Medical ideas deeply inform Kepler's theories of light and solar force (virtus motrix). It will become clear that they are not a hindrance even to the hardcore of his celestial physics. Instead, he makes use of soul and spiritus in order to develop a fully mathematized dynamics. PMID:24988759
Analytical Deriving of the Field Capacity through Soil Bundle Model
Arnone, E.; Viola, F.; Antinoro, C.; Noto, L. V.
2015-12-01
The concept of field capacity as soil hydraulic parameter is widely used in many hydrological applications. Althought its recurring usage, its definition is not univocal. Traditionally, field capacity has been related to the amount of water that remains in the soil after the excess water has drained away and the water downward movement experiences a significant decresase. Quantifying the drainage of excess of water may be vague and several definitions, often subjective, have been proposed. These definitions are based on fixed thresholds either of time, pressure, or flux to which the field capacity condition is associated. The flux-based definition identifies the field capacity as the soil moisture value corresponding to an arbitrary fixed threshold of free drainage flux. Recently, many works have investigated the flux-based definition by varying either the drainage threshold, the geometry setting and mainly the description of the drainage flux. Most of these methods are based on the simulation of the flux through a porous medium by using the Darcy's law or Richard's equation. Using the above-mentioned flux-based definition, in this work we propose an alternative analytical approach for deriving the field capacity based on a bundle-of-tubes model. The pore space of a porous medium is conceptualized as a bundle of capillary tubes of given length of different radii, derived from a known distribution. The drainage from a single capillary tube is given by the analytical solution of the differential equation describing the water height evolution within the capillary tube. This equation is based on the Poiseuille's law and describes the drainage flux with time as a function of tube radius. The drainage process is then integrated for any portion of soil taking into account the tube radius distribution which in turns depends on the soil type. This methodology allows to analytically derive the dynamics of drainage water flux for any soil type and consequently to define the
Analyses of HANARO bundle experiment data using MATRA-h: revision
International Nuclear Information System (INIS)
When the construction and operation license for HANARO was renewed in 1995, imposed was a condition that the safety limit CHFR should have the margin of 25 percent. The reason for this were that the number of bundle CHF experiment data was not enough for the validation of the prediction of CHF in bundle geometry and that the ability of COBRA/KMRR to prediction the local coolant condition was not fully validated. For the resolution of this imposition, more bundle CHF data were gathered and the subchannel exit temperature distribution was obtained during the in-core irradiation test of instrumented bundle (Type-B bundle). also, for these experimental data, subchannel analyses were performed by using MATRA-h code which is the modified version of MATRA-a which is a modified version of KAERI's MATRA-a for the application to HANARO. By comparing the analysis results with the experimental results, it was found that the HANARO subchannel analysis method would give the conservative or best-estimated predictions for the CHF in bundle geometry. This report is the revision of KAERI/TR-1090/98 on the analysis of bundle experiment data using MATRA-h. (Author). 16 refs., 16 tabs., 25 figs
Toward a Global Bundle Adjustment of SPOT 5 - HRS Images
Massera, S.; Favé, P.; Gachet, R.; Orsoni, A.
2012-07-01
The HRS (High Resolution Stereoscopic) instrument carried on SPOT 5 enables quasi-simultaneous acquisition of stereoscopic images on wide segments - 120 km wide - with two forward and backward-looking telescopes observing the Earth with an angle of 20° ahead and behind the vertical. For 8 years IGN (Institut Géographique National) has been developing techniques to achieve spatiotriangulation of these images. During this time the capacities of bundle adjustment of SPOT 5 - HRS spatial images have largely improved. Today a global single block composed of about 20,000 images can be computed in reasonable calculation time. The progression was achieved step by step: first computed blocks were only composed of 40 images, then bigger blocks were computed. Finally only one global block is now computed. In the same time calculation tools have improved: for example the adjustment of 2,000 images of North Africa takes about 2 minutes whereas 8 hours were needed two years ago. To reach such a result a new independent software was developed to compute fast and efficient bundle adjustments. In the same time equipment - GCPs (Ground Control Points) and tie points - and techniques have also evolved over the last 10 years. Studies were made to get recommendations about the equipment in order to make an accurate single block. Tie points can now be quickly and automatically computed with SURF (Speeded Up Robust Features) techniques. Today the updated equipment is composed of about 500 GCPs and studies show that the ideal configuration is around 100 tie points by square degree. With such an equipment, the location of the global HRS block becomes a few meters accurate whereas non adjusted images are only 15 m accurate. This paper will describe the methods used in IGN Espace to compute a global single block composed of almost 20,000 HRS images, 500 GCPs and several million of tie points in reasonable calculation time. Many advantages can be found to use such a block. Because the
A Reappraisal of Bennett Reimer and His Meanings of Art
Allsup, Randall Everett; Lewis, Judy
2015-01-01
Consistent throughout his writings on aesthetics and education, Bennett Reimer maintained the idea that music must be understood and studied as non-conceptual. Music's forms of knowing point to the subjective realms of life and operate effectively without the assistance or necessity of language. An education in the arts is an education in…
A contribution to understanding the structure of amphivasal secondary bundles in monocotyledons
Directory of Open Access Journals (Sweden)
Joanna Jura-Morawiec
2014-04-01
Full Text Available Secondary growth of monocotyledonous plants is connected with the activity of the monocot cambium that accumulates most of the derivatives inner to the cambial cylinder. These derivatives differentiate into (a secondary bundles with the amphivasal arrangement, i.e. xylem composed of tracheids surrounds the phloem cells and (b the parenchymatous secondary conjunctive tissue in which the bundles are embedded. The amphivasal secondary bundles differ in the arrangement of xylem cells as visible on single cross sections through the secondary body of the monocots. Apart from the bundles with typical ring of tracheids also the bundles where tracheids do not quite surround the phloem are present. We aimed to elucidate the cross sectional anatomy of the amphivasal secondary bundles with the use of the serial sectioning method which allowed us to follow very precisely the bundle structure along its length. The studies were carried out with the samples of secondary tissues collected from the stem of Dracaena draco L. growing in the greenhouses of the Polish Academy of Sciences Botanical Garden – CBDC in Powsin and the Adam Mickiewicz University Botanical Garden. The material was fixed in a mixture of glycerol and ethanol (1:1; v/v, dehydrated stepwise with graded ethanol series and finally embedded in epon resin. Afterwards, the material was sectioned with microtome into continuous series of thin (3 μm sections, stained with PAS/toluidine blue and examined under the light microscope. The results, described in details in Jura‑Morawiec & Wiland-Szymańska (2014, revealed novel facts about tracheids arrangement. Each amphivasal bundle is composed of sectors where tracheids form a ring as well as of such where tracheids are separated by vascular parenchyma cells. We hypothesize that strands of vascular parenchyma cells locally separating the tracheids enable radial transport of assimilates from sieve elements of the bundle towards the sink tissues, e
The button effect of CANFLEX bundle on the critical heat flux and critical channel power
Energy Technology Data Exchange (ETDEWEB)
Park, Joo Hwan; Jun, Jisu; Suk, Ho Chun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Dimmick, G. R.; Bullock, D. E.; Inch, W. [Atomic Energy of Canada Limited, Ontario (Canada)
1997-12-31
A CANFLEX (CANdu FLEXible fuelling) 43-element bundle has developed for a CANDU-6 reactor as an alternative of 37-element fuel bundle. The design has two diameter elements (11.5 and 13.5 mm) to reduce maximum element power rating and buttons to enhance the critical heat flux (CHF), compared with the standard 37-element bundle. The freon CHF experiments have performed for two series of CANFLEX bundles with and without buttons with a modelling fluid as refrigerant R-134a and axial uniform heat flux condition. Evaluating the effects of buttons of CANFLEX bundle on CHF and Critical Channel Power (CCP) with the experimental results, it is shown that the buttons enhance CCP as well as CHF. All the CHF`s for both the CANFLEX bundles are occurred at the end of fuel channel with the high dryout quality conditions. The CHF enhancement ratio are increased with increase of dryout quality for all flow conditions and also with increase of mass flux only for high pressure conditions. It indicates that the button is a useful design for CANDU operating condition because most CHF flow conditions for CANDU fuel bundle are ranged to high dryout quality conditions. 5 refs., 11 figs. (Author)
Lerman, Eugene
2003-01-01
We define contact fiber bundles and investigate conditions for the existence of contact structures on the total space of such a bundle. The results are analogous to minimal coupling in symplectic geometry. The two applications are construction of K-contact manifolds generalizing Yamazaki's fiber join construction and a cross-section theorem for contact moment maps
Principal noncommutative torus bundles
DEFF Research Database (Denmark)
Echterhoff, Siegfried; Nest, Ryszard; Oyono-Oyono, Herve
2008-01-01
of bivariant K-theory (denoted RKK-theory) due to Kasparov. Using earlier results of Echterhoff and Williams, we shall give a complete classification of principal non-commutative torus bundles up to equivariant Morita equivalence. We then study these bundles as topological fibrations (forgetting the...
Lacaille: astronomer, traveler. With a new translation of his journal.
Evans, D. S.
Nicolas Louis de la Caille (1713 - 1762) was the first systematic observer of the whole southern skies and delineator of fourteen new constellations in that hemisphere which survive to this day, as well as the pioneer geodesist and navigator. The book reviews the whole of his voluminous printed works and also includes a new translation of the manuscript diary of his adventurous southern voyages and travels in Brazil, South Africa and the Indian Ocean islands of Mauritius and Réunion. Illustrations include both reproductions of contemporary documents and modern photographs of some of the places which he visited.
THEBES: a thermal hydraulic code for the calculation of transient two phase flow in bundle geometry
International Nuclear Information System (INIS)
The three dimensional thermal hydraulic code THEBES, capable to calculate transient boiling of sodium in rod bundles is described here. THEBES, derived from the transient single phase code SABRE-2A, was developed in CADARACHE by the SIES to analyse the SCARABEE N loss of flow experiments. This paper also presents the results of tests which were performed against various types of experiments: (1) transient boiling in a 7 pin bundle simulating a partial blockage at the bottom of a subassembly (rapid transient SCARABEE 7.2 experiment), (2) transient boiling in a 7 pin bundle simulating a coolant coast down (slow transient SCARABEE 7.3 experiment), (3) steady local and generalised boiling in a 19 pin bundle (GR 19 I experiment), (4) transient boiling in a 19 pin bundle simulating a coolant coast down (GR 19 I experiment), (5) steady local boiling in a 37 pin bundle with internal blockage (MOL 7C experiment). Excellent agreement was found between calculated and experimental results for these different situations. Our conclusion is that THEBES is able to calculate transient boiling of sodium in rod bundles in a quite satisfying way
CFD analysis of flow and heat transfer in Canadian supercritical water reactor bundle
International Nuclear Information System (INIS)
Highlights: • Flow and heat transfer in SCWR fuel bundle design by AECL is studied using CFD. • Bare-rod bundle geometry is tested at 23.5, 25 and 28 MPa using STAR-CCM+ code. • SST k–ω low-Re model was used to study occurrence of heat transfer deterioration. - Abstract: Within the Gen-IV International Forum, AECL is leading the effort in developing a conceptual design for the Canadian SCWR. AECL proposed a new fuel bundle design with two rings of fuel elements placed between central flow tube and the pressure tube. In line with the scope of the conceptual design, the objective of the present CFD work is to aid in developing a bundle heat transfer correlation for the Canadian SCWR fuel bundle design. This paper presents results from an ongoing effort in determining the conditions favorable for occurrence of HTD in the supercritical bundle flows. In the current investigation, bare-rod bundle geometry was tested for the proposed fuel bundle design at 23.5, 25 and 28 MPa using STAR-CCM+ CFD code. Taking advantage of the design symmetry of the fuel bundle, only 1/32 of the computational domain was simulated. The low-Reynolds number modification of SST k–ω turbulence model along with y+ < 1 was used in the simulations. For lower mass flow simulations, the increase of inlet temperature and operational pressure was found effective in reducing the occurrence of HTD. For higher mass flow simulations, normal heat transfer behaviour was observed except for the lower pressure range (23.5 MPa)
Bahl, Vibhu; Goyal, Ankit; Jain, Vineet; Joshi, Deepak; Chaudhary, Deepak
2013-01-01
Background Haemarthrosis and pain adversely affects the functional outcome of ACL reconstruction, especially in case of DB ACL reconstruction due to more extensive procedure. The purpose of the study was to evaluate the effect of haemarthrosis on the rehabilitation of DB ACL reconstruction versus SB ACL reconstruction. Methods 100 patients were divided into two groups, of SB ACL and DB ACL reconstruction consisting of 50 patients each. An intra-articular drain was put in every patient. The pa...
Canflex: A fuel bundle to facilitate the use of enrichment and fuel cycles in CANDU reactors
International Nuclear Information System (INIS)
The neutron economy of the CANDU reactor results in it being an ideal host for a number of resource-conserving fuel cycles, as well as a number of potential ''symbiotic'' fuel cycles, in which fuel discharged from light-water cooled reactors is recycled to extract the maximum energy from the residual fissile material before it is sent for disposal. The resource conserving fuel cycles include the natural-uranium, slightly-enriched-uranium and thorium fuel cycles. The ''LWR-symbiotic'' cycles include recovered uranium and various options for the direct use of spent LWR fuel in CANDU reactors. However, to achieve the maximum economic potential of these fuel-cycle options requires irradiation to burnups higher than that possible with natural uranium. To provide a basis for the economic use of these fuel cycles, a program is underway to develop and demonstrate a CANDU fuel bundle capable of both higher burnups and greater operating margins. This new bundle design is being developed jointly by AECL and KAERI, and uses smaller-diameter fuel elements in the outer ring of a 43-element bundle to reduce the maximum element ratings in a CANDU fuel bundle by 20% compared to the 37-element bundle currently in use. This allows operation to burnups greater than 21 MWd/KgU. A combination of this lower peak-element rating, plus development work underway at AECL to enhance the thermalhydraulic characteristics of the bundle (including both critical heat flux and bundle pressure drop), provides a greater operating margin for the bundle. This new bundle design is called CANFLEX, and the program for its development in Canada and Korea is described in this paper. (author). 19 refs, 5 figs
Institute of Scientific and Technical Information of China (English)
Jinxun Wang; Mingzhe Dong; Jun Yao
2012-01-01
Analytical expressions of relative permeability are derived for an interacting cylindrical tube bundle model.Equations for determining relative permeability curves from both the interacting uniform and interacting serial types of triangular tube bundle models are presented.Model parameters affecting the trend of relative permeability curves are discussed.Interacting triangular tube bundle models are used to history-match laboratory displacement experiments to determine the relative permeability curves of actual core samples.By adjusting model parameters to match the history of oil production and pressure drop,the estimated relative permeability curves provide a connection between the macroscopic flow behavior and the pore-scale characteristics of core samples.
Poincar\\'e Families of G-Bundles on a curve
Biswas, Indranil
2010-01-01
Let G be a reductive group over an algebraically closed field k. Consider the moduli space of stable principal G-bundles on a smooth projective curve C over k. We give necessary and sufficient conditions for the existence of Poincar\\'e bundles over open subsets of this moduli space, and compute the orders of the corresponding obstruction classes. This generalizes the previous results of Newstead, Ramanan and Balaji-Biswas-Nagaraj-Newstead to all reductive groups, to all topological types of bundles, and also to all characteristics.
Temperature response of bundle-sheath conductance in maize leaves.
Yin, Xinyou; van der Putten, Peter E L; Driever, Steven M; Struik, Paul C
2016-04-01
A small bundle-sheath conductance (g bs) is essential for the C4 CO2-concentrating mechanism to suppress photorespiration effectively. To predict the productivity of C4 crops accurately under global warming, it is necessary to examine whether and how g bs responds to temperature. We investigated the temperature response of g bs in maize by fitting a C4 photosynthesis model to combined gas exchange and chlorophyll fluorescence measurements of irradiance and CO2 response curves at 21% and 2% O2 within the range of 13.5-39 °C. The analysis was based on reported kinetic constants of C4 Rubisco and phosphoenolpyruvate carboxylase and temperature responses of C3 mesophyll conductance (g m). The estimates of g bs varied greatly with leaf temperature. The temperature response of g bs was well described by the peaked Arrhenius equation, with the optimum temperature being ~34 °C. The assumed temperature responses of g m had only a slight impact on the temperature response of g bs In contrast, using extreme values of some enzyme kinetic constants changed the shape of the response, from the peaked optimum response to the non-peaked Arrhenius pattern. Further studies are needed to confirm such an Arrhenius response pattern from independent measurement techniques and to assess whether it is common across C4 species. PMID:26969744
Augustine as a Reader of His Christian Contemporaries
Williams, Michael Stuart
2012-01-01
Augustine was not a great reader of his Christian contemporaries. That is to say, he seems not to have expended every energy (as might be expected of a modern scholar) in keeping up with the very latest to have been written on every topic on which he pronounced, or in which he could claim an interest. Part of the reason for this must be his relatively late conversion to Christianity. For as O’Donnell has pointed out, Augustine the professor of rhetoric – as he was by the time h...
International Nuclear Information System (INIS)
This patent describes a method of forming a fuel bundle of a nuclear reactor. The method consists of positioning the fuel rods in the bottom plate, positioning the tie rod in the bottom plate with the key passed through the receptacle to the underside of the bottom plate and, after the tie rod is so positioned, turning the tie rod so that the key is in engagement with the underside of the bottom plate. Thereafter mounting the top plate is mounted in engagement with the fuel rods with the upper end of the tie rod extending through the opening in the top plate and extending above the top plate, and the tie rod is secured to the upper side of sid top plate thus simultaneously securing the key to the underside of the bottom plate
Twisted Vector Bundles on Pointed Nodal Curves
Indian Academy of Sciences (India)
Ivan Kausz
2005-05-01
Motivated by the quest for a good compactification of the moduli space of -bundles on a nodal curve we establish a striking relationship between Abramovich’s and Vistoli’s twisted bundles and Gieseker vector bundles.
Dryout power of a CANFLEX bundle string with raised bearing pads
International Nuclear Information System (INIS)
Dryout power data have been obtained with CANFLEX bundle strings equipped with raised bearing pads (1.7 mm and 1.8 mm height as compared to 1.4 mm in the current Mk-IV design) at Stern Laboratories. The experiment covered a wide range of steam-water flow conditions in three flow tubes simulating uncrept, and 3.3% and 5.1% crept profiles. The dryout power follows consistent parametric trends: it increases with increasing mass-flow rate, and decreases with increasing pressure, inlet-fluid temperature and channel creep. Local and boiling-length-average (BLA) critical-heat-flux (CHF) values were evaluated from the dryout-power measurements. The dryout power and BLA CHF values of the high bearing-pad bundles are higher than those of the low bearing-pad bundles at the same channel inlet flow conditions. On average, the dryout powers for bundles with 1.7 mm and 1.8 mm bearing pads are about 8% and 10%, respectively, higher than those for the bundle with 1.4 mm bearing pads. Compared to the 37-element bundle, an enhancement in dryout power is shown with CANFLEX bundles for all bearing-pad heights, at flow conditions of interest for reactor licensing. The average dryout power enhancement varies from 4% for the CANFLEX bundle with 1.4 mm bearing pads in the uncrept channel to 27% for the CANFLEX bundle with 1.8 mm bearing pads in the 5.1% crept channel. (author)
Studies of a larger fuel bundle for the ABWR improved evolutionary reactor
International Nuclear Information System (INIS)
Studies for an Improved Evolutionary Reactor (IER) based on the Advanced Boiling Water Reactor (ABWR) were initiated in 1990. The author summarizes the current status of the core and fuel design. A core and fuel design based on a BWR K-lattice fuel bundle with a pitch larger than the conventional BWR fuel bundle pitch is under investigation. The core and fuel design has potential for improved core design flexibility and improved reactor transient response. Furthermore, the large fuel bundle, coupled with a functional control rod layout, can achieve improvement of operation and maintenance, as well as improvement of overall plant economy
The wrapped Fukaya category of a negative line bundle
Ritter, Alexander F
2012-01-01
Let B be a closed monotone symplectic manifold with divisible first Chern class c_1(B) = Kc. Let E be the total space of the monotone negative line bundle over B with first Chern class kc for 0 < k < K. We prove that if the open-closed string map from the Hochschild homology of the Fukaya category of B to its quantum cohomology hits an invertible element, then the wrapped Fukaya category of E is split-generated by closed Lagrangians, hence is cohomologically finite. The proof combines quilt-maps on Hochschild homology, Abouzaid's generation criterion (which we extend from exact to monotone convex manifolds), and the quantum cohomology module structure of the open-closed string map. As illustrations, we show that when B is toric Fano, the wrapped category of E is split-generated by toric fibres (and is usually non-empty, in particular E contains a non-displaceable monotone Lagrangian torus), and we outline a proof (contingent upon forthcoming work of Ganatra and Abouzaid-Fukaya-Oh-Ohta-Ono) that the Jaco...
Defects in Crystalline Packings of Twisted Filament Bundles: I. Continuum Theory of Disclinations
Grason, Gregory M.
2011-01-01
We develop the theory of the coupling between in-plane order and out-of-plane geometry in twisted, two-dimensionally ordered filament bundles based on the non-linear continuum elasticity theory of columnar materials. We show that twisted textures of filament backbones necessarily introduce stresses into the cross-sectional packing of bundles and that these stresses are formally equivalent to the geometrically-induced stresses generated in thin elastic sheets that are forced to adopt spherical...
Quantum Sheaf Cohomology on surfaces of general type I: construction of stable omalous bundles
Anghel, Cristian
2015-01-01
Quantum sheaf cohomology is a deformation of the cohomology ring of a sheaf. In recent years, this subject had an impetuous development in connection with the $(0; 2)$ non-linear sigma model from super-strings theory. The basic piece in this area is a so-called omalous bundle on the variety we start with. After a short overview of the subject, we construct stable omalous bundles on some classes of surfaces of general type.
Experimental investigation of water sprayed finned heat exchanger tube bundles
International Nuclear Information System (INIS)
Experimental investigations have been made to study the performance of two finned tube-bundle heat exchangers (FORGO type) when wetted by water sprays. The heat exchangers are designed to cool water in a dry cooling tower. The test-elements had a frontal area of 1 m2. The water sprays were created by 20 nozzles, 200 mm in front of the heat exchangers. Air velocities at the inlet of the coolers were in the range 0,8 m/s to 12 m/s and initial temperature differences ITD reached 45 degrees C. The test facility was designed to determine the combined latent and sensible heat fluxes in the wetted heat exchanger, the airside pressure drop and the air humidity and temperature at the exchanger inlet and outlet, and to measure the weight of the water wetting the cooler's surface. The sprayed test elements were investigated in different positions, but most of the experiments were carried out in the position with the fins horizontal
Degenerations of the moduli spaces of vector bundles on curves
International Nuclear Information System (INIS)
Let Y be a smooth projective curve of genus g and UY = UY (n; d) the moduli space of (semi-stable) vector bundles on Y of rank n and degree d. One strategy for studying the variety UY in depth is by the method of degeneration (or specialization), namely one specializes Y to a curve X0, say with only one singularity which is an ordinary double point. One would have a moduli object UX0 on X0 such that UY specializes to UX0 and one expects a close relationship between UX0 and the moduli space UX on the normalisation X of X0. Since the genus of X is (g-1), one would then obtain a machinery for studying UY , especially its properties which are amenable to specialization, by induction on g. This strategy was employed by Gieseker to prove a conjecture of Newstead and Ramanan for moduli spaces in rank 2, namely that the Chern classes ci of the smooth projective variety UY (2; 1) vanish for i > 1/2 dimUY (2; 1), i.e. i >= (2g - 1), since dimUY (2; 1) = (4g - 3). A similar one was employed by M.S. Narasimhan and T.R. Ramadas to prove what is called the factorisation rule in the rank two case and recently it has been generalized to arbitrary rank by Xiaotao Sun. Gieseker constructed a moduli object GX0 on X0 (we do not denote this by UX0 since this will stand for a moduli space of torsion free sheaves on X0) such that it has nice singularities and UY (2; 1) specializes to GX0 . Further, he gave a concrete realization of GX0 via the moduli space UX(2; 1), which helps in solving the conjecture of Newstead and Ramanan by induction on the genus. Recently, in collaboration with D.S. Nagaraj, we have been able to generalize Gieseker's construction of GX0 for arbitrary rank. A good part of these lectures is devoted to outlining this construction. Our method for the global construction is quite different from that of Gieseker; it consists in relating the Gieseker moduli space to that of torsion free sheaves on X0, an aspect which does not figure in Gieseker's work. We give also a
THE PUPIL AS THE SUBJECT OF HIS EDUCATIONAL ACTIVITY
Selivanova, Olga
2014-01-01
The article describes the author΄s approach to the formation of subjectivity of the pupil in his educational activity and the relationship between the main concepts. The author regards subjectivity of the pupil as a pedagogical phenomena and characterizes the set of the pedagogical conditions of the formation of it.
Invariants of Velocities, and Higher Order Grassmann Bundles
Grigore, D R; Grigore, Dan Radu; Krupka, Demeter
1997-01-01
An $(r,n)$-velocity is an $r$-jet with source at $0 \\in \\R^n$, and target in a manifold $Y$. An $(r,n)$-velocity is said to be regular, if it has a representative which is an immersion at $0 \\in \\R^{n}$. The manifold $T^{r}_{n}Y$ of $(r,n)$-velocities as well as its open, $L^{r}_{n}$-invariant, dense submanifold $\\Imm T^{r}_{n}Y$ of regular $(r,n)$-velocities, are endowed with a natural action of the differential group $L^{r}_{n}$ of invertible $r$-jets with source and target $0 \\in \\R^{n}$. In this paper, we describe all continuous, $L^{r}_{n}$-invariant, real-valued functions on $T^{r}_{n}Y$ and T^{r}_{n}Y$ in an explicit, recurrent form. To this purpose, higher order Grassmann bundles are considered as the corresponding quotients $P^{r}_{n}Y = that nontrivial $L^{r}_{n}$-invariants on $\\Imm T^{r}_{n}Y$ cannot be continuously extended onto $T^{r}_{n}Y$.
Status of the demonstration irradiation of the CANDU new fuel bundle CANFLEX-NU in Korea
International Nuclear Information System (INIS)
A demonstration irradiation (DI) of 24 KNFC made CANFLEX-NU fuel bundles in the Wolsong Power Generation Station-i has been conducted jointly by KEPRI/KHNP/KAERI since July 10, 2002. By selecting the Q07 (high power) and L21(low power) channels, the total 24 and 16 CANFLEX bundles were respectively loaded into and discharged from the reactor by 2003 August, and the final discharge of the other 8 CANFLEX bundles is expected on around February 2004. Tracking the reactor operation data, it is noted that the reactor has been stably operated during the DI. One CANFLEX bundle irradiated in the Q07 channel had a typical history of high power and high burnup, having the outer element power rating of ∼ 41 kW/m at the fuelling, ∼ 42 kW/m as a maximum power rating at the burnup of ∼ 50 MWh/kgU, and ∼ 35 kW/m at the discharge burnup of ∼ 210 MWh/kgU. While, another CANFLEX bundle also irradiated in the Q07 channel had a typical history of power ramping, having a outer element power rating of ∼ 7 kW/m from the fuelling to the burnup of ∼ 48 MWh/kgU at which the element powers were ramped to a ∼ 35 kW/m maximum element power rating, and ∼ 30 kW/m at the discharge burnup of 188 MWh/kgU. An unusual performance and integrity of the CANFLEX elements could not be found in the ELESTRES predictions. By looking at the discharged CANFLEX bundles in the bay, all the bundles were intact, free of defects and appeared to be in good condition. A detailed in-bay visual examinations and dimensional measurements of the discharged CANFLEX bundles will be made at the end of 2003. (author)
Antonio Gramsci and His Relevance for the Education of Adults
Mayo, Peter
2008-01-01
This paper, drawing on original sources, provides an overview of and a discussion on those writings and ideas, in Antonio Gramsci's huge corpus of work, that are relevant to the education of adults. This should provide a fitting tribute to this major social theorist of the 20th century on the 70th anniversary of his death. Among the topics…
Weibull statistics of bamboo fibre bundles: methodology for tensile testing of natural fibres
Trujillo De Los Rios, Efrain Eduardo; Moesen, Maarten; Osorio Serna, Lina Rocío; Van Vuure, Aart Willem; Ivens, Jan; Verpoest, Ignace
2012-01-01
In order to characterize bamboo (Guadua angustifolia) fibres mechanically, single fibre (SFT), dry fibre bundle (DFB) and impregnated bundle (IFB) tests were performed. It was found that the strength of the fibres follows a Weibull distribution, furthermore showing that the variability of the material (obtained from the shape parameter m=8.3) is relatively low. The tensile strength of the fibres was around 800 MPa (SFT). In order to determine experimentally the two Weibull parameters from loa...
Numerical investigation of heat transfer characteristic of fixed planar elastic tube bundles
International Nuclear Information System (INIS)
Highlights: • Both tube-side and shell-side of planar elastic tube bundles were investigated. • Heat transfer and fluid flow were studied from the local analysis perspective. • Secondary flow varies depending on the fluid flow state and the geometry of tube. • Curvature plays a role on the external flow field. • The heat transfer of the two intermediate tube bundles is augmented. - Abstract: Planar elastic tube bundles are a novel approach to enhance heat transfer by using flow-induced vibration. This paper studied the heat transfer characteristic and fluid flow in both tube-side and shell-side using numerical simulation. Two temperature difference formulas were used to calculate convective heat transfer coefficient and the results were verified by theoretical analysis and experimental correlations. The effect of Reynolds number on overall convective heat transfer coefficient and pressure drop in tube-side and shell-side were studied. The comparison of the secondary flow in planar elastic tube bundles and conical spiral tube bundles were conducted. The external flow field and local convective heat transfer around the periphery of fixed planar elastic tube bundles subjected to the cross fluid flow were also analyzed. The results show that the energy consumption efficiency should be taken into account in the forced heat transfer process conducted by adjusting the fluid flow. The secondary flow varies depending on the fluid flow state and the geometry of tube. Hence, it is deduced that the heat transfer enhancement is obtained because the thermal boundary layer in the deformed planar elastic tube bundles caused by flow-induced vibration is damaged by the disordered secondary flow. In addition, the convective heat transfer capability of outside the two intermediate tube bundles is enhanced because of the effect of irregular and complex fluid flow affected by the role of curved tubes on both sides
William Boog Leishman-A Brief Reminder of His Life and Work on the Occasion of His 150th Birthday.
Weyers, Wolfgang
2016-06-01
William Boog Leishman was born 150 years ago. Although his description of "small round or oval bodies" in a smear from the spleen pulp of a soldier who had died of kala-azar was not the first one of Leishmania and although Leishman did not make the diagnosis of kala-azar and misinterpreted the microorganisms to be trypanosomes, his article became the springboard for a series of studies that, within a few months, established Leishmania as a previously unknown genus of protozoa and led to appreciation of the clinical spectrum of kala-azar and the relationship between cutaneous and visceral leishmaniasis. PMID:27205906
Total evaluation of in bundle void fraction measurement test of PWR fuel assembly
International Nuclear Information System (INIS)
Nuclear Power Engineering Corporation is performing the various proof or verification tests on safety and reliability of nuclear power plants under the sponsorship of the Ministry of International Trade and Industry. As one program of these Japanese national projects, an in bundle void fraction measurement test of a pressurized water reactor (PWR) fuel assembly was started in 1987 and finished at the end of 1994. The experiments were performed using the 5 x 5 square array rod bundle test sections. The rod bundle test section simulates the partial section and full length of a 17 x 17 type Japanese PWR fuel assembly. A distribution of subchannel averaged void fraction in a rod bundle test section was measured by the gamma-ray attenuation method using the stationary multi beam systems. The additional single channel test was performed to obtain the required information for the calibration of the rod bundle test data and the assessment of the void prediction method. Three test rod bundles were prepared to analyze an axial power distribution effect, an unheated rod effect, and a grid spacer effect. And, the obtained data were used for the assessment of the void prediction method relevant to the subchannel averaged void fraction of PWR fuel assemblies. This paper describes the outline of the experiments, the evaluation of the experimental data and the assessment of void prediction method
[A toddler with a swelling of his penis].
Staps, P; Smeets, C C J M
2016-01-01
A 4-year-old boy presented with a subcutaneous, yellowish swelling of 0.8 by 1.5 cm on his penis. We made the diagnosis of a smegma retention cyst. This cyst is the result of a physiologic phenomenon that originates from the separation of the foreskin. PMID:27405570
Einstein: a lecture on the centenary of his birth
International Nuclear Information System (INIS)
The life, the personality, the work and also the way of working of Albert Einstein are discussed. His work reviewed includes that on the Brownian motion, light quanta, relativity, the concept of time, gravitation and the philosophy of science. (U.K.)
Properties of the microcirculation in capillary bundles of rat spinotrapezius muscle fascia
Jacobitz, Frank; Engebrecht, Cheryn; Metzger, Ian; Porterfield, Colin
2006-11-01
Properties of the microcirculation in capillary bundles of rat spinotrapezius muscle fascia are investigated using microscope observations, empirical modeling, and numerical simulations. Capillary bundles consist of a network of feeding arterioles, draining venules, and capillary vessels. A dozen samples of muscle fascia tissue were prepared for microscope observation. The chosen method of preparation allows for the long-term preservation of the tissue samples for future studies. Capillary bundles are photographed under a microscope with 40x magnification. From the images, the microvasculature of the tissue samples is reconstructed. It was found, for example, that the distribution of vessel length in a capillary bundle follows a log-normal law. In addition to a statistical analysis of the vessel data, the network topology is used for numerical simulations of the flow in the capillary bundles. The numerical approach uses a sparse-matrix solver and it considers vessel elasticity and blood rheology. The numerical simulations show, for example, a strong pressure drop across the capillary vessels of the bundle.
The effects of bearing-pad height on the critical heat flux of CANFLEX fuel bundle
International Nuclear Information System (INIS)
In CANDU-6 fuel channel, the geometrical eccentricity exists between fuel bundle and horizontal pressure tube. Based on the water CHF(critical heat flux) tests of the full-scale CANFLEX(CANDU Flexible) bundle string with the current bearing-pads of 1.4mm height, it was found that the increase of bypassing flow decreased significantly the CHF of fuel bundle with increasing the creep rate of pressure tube. So, the additional improvement of heat transfer performance is anticipated by increasing the hight of bearing-pads(about 0.3 mm) and reducing the eccentricity of fuel bundle. This paper presented the effects of bearing-pad height on the CHF by examining the water CHF test data of CANFLEX fuel strings equipped with 1.7 mm and 1.8 mm high bearing-pads. It also showed the data trends of the boiling-length-averaged CHF with respect to the test system flow parameters and local flow conditions. The high bearing-pad bundle is increased in dryout power by 7 to 10%, compared to the current CANFLEX fuel bundle
Nuclear regulations for the protection of man and his environment
International Nuclear Information System (INIS)
This article describes in brief the activities of the Philippine Atomic Energy Commission (PAEC) in the exercise of its regulatory function to safeguard man and his environment in the operation of the first Philippine Nuclear Power Plant (PNPP-1). PAEC's role includes regulations, quality assurance, audit, regulatory research and radiological emergency planning. (ELC)
Magnus Strandqvist: 50th anniversary of his doctoral thesis.
Kajanti, M J
1994-01-01
This article is dedicated to Magnus Strandqvist's famous doctoral thesis "Studien über die kumulative Wirkung der Röntgenstrahlen bei Fraktionierung. Erfahrungen aus dem Radiumhemmet an 280 Haut- und Lippenkarzinomen" published in Acta Radiologica in 1944. After a short biography of Strandqvist some central points of his work and their influence on future development of modern radiotherapy are presented. PMID:7993639
Energy Technology Data Exchange (ETDEWEB)
Johnson, M.R.; Rols, S.; Wass, P.; Muris, M.; Bienfait, M.; Zeppenfeld, P.; Dupont-Pavlovsky, N
2003-09-01
Neutron diffraction measurements on a powder sample of bundles of single-walled carbon nanotubes are used to gain insight into adsorption sites for methane molecules. In parallel, numerical methods, based on empirical force-fields, are employed to calculate the adsorption of methane in bundles of nanotubes and neutron diffraction patterns based on these structures. Adsorption sites in grooves on the outer surface of bundles and on the curved surfaces of the nanotubes are characterised by their binding energy and relative abundance. Comparison with published adsorption isotherms indicate that the more stable groove sites must also be complemented by interstitial sites. Such sites are found to be energetically unfavourable in homogeneous bundles composed of average diameter nanotubes, but can become favourable in bundles made of bigger diameter tubes and in more realistic, heterogeneous bundles. Nanotube deformation is an important factor, limiting the size of interstitial channels, but also allowing the stabilisation of adsorbed methane molecules. Diffraction patterns calculated for methane-nanotube structures with partially occupied interstitial sites are in best agreement with the experimental diffraction data.
International Nuclear Information System (INIS)
Neutron diffraction measurements on a powder sample of bundles of single-walled carbon nanotubes are used to gain insight into adsorption sites for methane molecules. In parallel, numerical methods, based on empirical force-fields, are employed to calculate the adsorption of methane in bundles of nanotubes and neutron diffraction patterns based on these structures. Adsorption sites in grooves on the outer surface of bundles and on the curved surfaces of the nanotubes are characterised by their binding energy and relative abundance. Comparison with published adsorption isotherms indicate that the more stable groove sites must also be complemented by interstitial sites. Such sites are found to be energetically unfavourable in homogeneous bundles composed of average diameter nanotubes, but can become favourable in bundles made of bigger diameter tubes and in more realistic, heterogeneous bundles. Nanotube deformation is an important factor, limiting the size of interstitial channels, but also allowing the stabilisation of adsorbed methane molecules. Diffraction patterns calculated for methane-nanotube structures with partially occupied interstitial sites are in best agreement with the experimental diffraction data
Hierarchical composites: Analysis of damage evolution based on fiber bundle model
DEFF Research Database (Denmark)
Mishnaevsky, Leon
2011-01-01
A computational model of multiscale composites is developed on the basis of the fiber bundle model with the hierarchical load sharing rule, and employed to study the effect of the microstructures of hierarchical composites on their damage resistance. Two types of hierarchical materials were...... considered: “hierarchical tree” (bundles-of-bundles of fibers) and self-similar particle and fiber reinforced composite (in which reinforcements at each scale level represents composites in turn consisting of lower level reinforcements and matrix). For the case of the hierarchical tree (“bundle...... hierarchy levels. The effect of mixed fiber and particle reinforcement on the damage resistance of the hierarchical composites is investigated as well....
Some recent developments in the theory of acoustic transmission in tube bundles
Heckl, Maria A.; Mulholland, L. S.
1995-01-01
A comprehensive theoretical model for acoustic transmission in a tube bundle is presented. The tube bundle is considered as a series of diffraction gratings. Each grating consists of periodically spaced cylindrical tubes which obey the equations of motion of a cylindrical shell. Fluid loading is included. The model can be used for numerical simulations to calculate the sound field at any point in a tube bundle. Various phenomena can be predicted which are of interest for the development of acoustic diagnostics in heat exchangers. These include diffraction of a plane incident wave into several directions, the occurrence of passing and stopping bands in the transmission spectrum, features specific to oblique waves and the effect of dissipative losses. Tube bundles with baffle plates are also examined. The validity of the theoretical model is confirmed by comparison with experimental results.
Standardization of Type 2 Diabetes Outpatient Expenditure with Bundled Payment Method in China
Guo-Chao Xu; Yun Luo; Qian Li; Meng-Fan Wu; Zi-Jun Zhou
2016-01-01
Background: In recent years, the prevalence of type 2 diabetes among Chinese population has been increasing by years, directly leading to an average annual growth rate of 19.90% of medical expenditure. Therefore, it is urgent to work on strategies to control the growth of medical expenditure on type 2 diabetes on the basis of the reality of China. Therefore, in this study, we explored the feasibility of implementing bundled payment in China through analyzing bundled payment standards of type ...
The Role of Cyclo(His-Pro) in Neurodegeneration
Grottelli, Silvia; Ferrari, Ilaria; Pietrini, Grazia; Peirce, Matthew J.; Minelli, Alba; Bellezza, Ilaria
2016-01-01
Neurodegenerative diseases may have distinct genetic etiologies and pathological manifestations, yet share common cellular mechanisms underpinning neuronal damage and dysfunction. These cellular mechanisms include excitotoxicity, calcium dysregulation, oxidative damage, ER stress and neuroinflammation. Recent data have identified a dual role in these events for glial cells, such as microglia and astrocytes, which are able both to induce and to protect against damage induced by diverse stresses. Cyclo(His-Pro), a cyclic dipeptide derived from the hydrolytic removal of the amino-terminal pyroglutamic acid residue of the hypothalamic thyrotropin-releasing hormone, may be important in regulating the nature of the glial cell contribution. Cyclo(His-Pro) is ubiquitous in the central nervous system and is a key substrate of organic cation transporters, which are strongly linked to neuroprotection. The cyclic dipeptide can also cross the brain-blood-barrier and, once in the brain, can affect diverse inflammatory and stress responses by modifying the Nrf2-NF-κB signaling axis. For these reasons, cyclo(His-Pro) has striking potential for therapeutic application by both parenteral and oral administration routes and may represent an important new tool in counteracting neuroinflammation-based degenerative pathologies. In this review, we discuss the chemistry and biology of cyclo(His-Pro), how it may interact with the biological mechanisms driving neurodegenerative disease, such as amyotrophic lateral sclerosis, and thereby act to preserve or restore neuronal function. PMID:27529240
On framed quantum principal bundles
Durdevic, M
1995-01-01
A noncommutative-geometric formalism of framed principal bundles is sketched, in a special case of quantum bundles (over quantum spaces) possessing classical structure groups. Quantum counterparts of torsion operators and Levi-Civita type connections are analyzed. A construction of a natural differential calculus on framed bundles is described. Illustrative examples are presented.
Flow-induced vibration and acoustic behaviour of CANFLEX-LVRF bundles in a Bruce B NGS fuel channel
International Nuclear Information System (INIS)
Frequency/temperature sweep tests were performed in a high-temperature/high-pressure test channel to determine the acoustic and flow-induced vibration characteristics of the CANFLEX-LVRF bundle. The vibratory response of CANFLEX-LVRF bundles was compared with that of 37-element fuel bundles under Bruce B NGS fuel channel normal operating conditions. The tests were performed with a 12-bundle string of CANFLEX-LVRF bundles as well as a mixed string for the transition core. The tests showed that the LVRF bundles performed as required without failure or gross geometry changes. The mixed fuel strings behaved in a manner similar to that of a string of CANFLEX-LVRF bundles. (author)
Tangent-bundle approach for the factorization of gauge theories in a supergroup manifold
International Nuclear Information System (INIS)
Gauge theories of gravity and supergravity on a supergroup manifold are analysed as geometrical theories on the tangent bundle to a supergroup manifold. The factorization condition is considered from this point of view
Tangent-bundle approach for the factorization of gauge theories in a supergroup manifold
Energy Technology Data Exchange (ETDEWEB)
Foussats, A.; Laura, R.; Zandron, O.
1986-03-11
Gauge theories of gravity and supergravity on a supergroup manifold are analysed as geometrical theories on the tangent bundle to a supergroup manifold. The factorization condition is considered from this point of view.
Development of Romanian SEU-43 fuel bundle for CANDU type reactors
International Nuclear Information System (INIS)
SEU-43 fuel bundle is a CANDU type fuel consisting of two element sizes, to reduce element ratings, while maintaining the same bundle power, and an uranium content very close to the uranium content of a standard 37-element bundle. In order to reduce the detrimental effects of the life limiting factors at extended burnup a set of solution have been adopted for fuel element design. As a part of the design verification program, experimental bundles have been fabricated and utilized in typical out of reactor tests conducted at the laboratories of INR, Pitesti. These tests simulated current CANDU-6 reactor normal operating conditions of flow, temperature and pressure. The results are in accordance with the specified acceptance criteria. (author)
Stochastic poisson equations associated to lie algebroids and some refinements of a principal bundle
Ivan, Gheorghe
2010-01-01
The aim of this paper is to present the stochastic Poisson equations associated to Lie algebroids. The stochastic Poisson equations associated to a refinement of a concrete principal bundle are determined.
Simulation of flow across complicated domain between tube bundles by the discrete vortex method
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
On the basis of the analysis of numerical simulation methods for the complicated domain between tube bundles, an improved Lagragian discrete vortex method (DVM) and corresponding algorithm are put forward to solve the practical difficulties of flow across tube bundles. With this method the amount of vortices can be reduced considerably, which makes quick calculation possible. Applied to the practical configuration of horizontal tube bundles, the DVM simulation is carried out and compared with the experimental results. Both the transient flow field and the profile of mean velocity and fluctuations are in good agreement with experimental results, which indicate that the DVM is suitable for the simulation of single-phase flow across tube bundles.
Post-test examination of the VVER-1000 fuel rod bundle CORA-W2
Energy Technology Data Exchange (ETDEWEB)
Hofmann, P.; Noack, V.; Burbach, J.; Metzger, H.; Schanz, G.; Hagen, S.; Sepold, L.
1995-08-01
The upper half of the bundle is completely oxidized, the lower half has kept the fuel rods relatively intact. The post-test examination results show the strong impact of the B{sub 4}C absorber rod and the stainless steel grid spacers on the `low-temperature` bundle damage initiation and progression. The B{sub 4}C absorber rod completely disappeared in the upper half of the bundle. The multicomponent melts relocated and formed coolant channel blockages on solidification with a maximum extent of about 30% in the lower part of the bundle. At temperatures above the melting point of the ZrNb1 cladding extensive fuel dissolution occured. (orig./HP)
Jay Pil Choi
2003-01-01
This paper develops a simple model to analyze the effects of mergers in complementary system markets when the merged firm is able to engage in bundling. In the short-run analysis, I analyze the impact of (mixed) bundling on pricing decisions for existing generations of products. The basic model is then extended to analyze industry dynamics where the implications of mergers for innovation incentives and technical tying/compatibility decisions are explored. Welfare implications of mergers in th...
Method of fabricating high-density hermetic electrical feedthroughs using insulated wire bundles
Energy Technology Data Exchange (ETDEWEB)
Shah, Kedar G.; Benett, William J.; Pannu, Satinderpall S.
2016-05-10
A method of fabricating electrical feedthroughs coats of a plurality of electrically conductive wires with an electrically insulating material and bundles the coated wires together in a substantially parallel arrangement. The bundled coated wires are secured to each other by joining the electrically insulating material of adjacent wires together to form a monolithic block which is then cut transverse to the wires to produce a block section having opposing first and second sides with a plurality of electrically conductive feedthroughs extending between them.
International Nuclear Information System (INIS)
As part of the design verification program for the new fuel bundle, a series of out-reactor tests was conducted on the CANFLEX 43-element fuel bundle design. These tests simulated current CANDU 6 reactor normal operating conditions of flow, temperature and pressure. This paper describes the Quality Assurance (QA) Program implemented for the tests that were run at the testing laboratories of Atomic Energy of Canada Limited (AECL) and Korea Atomic energy Research Institute (KAERI). (author)
Dressed elliptic genus of heterotic compactifications with torsion and general bundles
Israel, Dan
2016-01-01
We define and compute the dressed elliptic genus of N = 2 heterotic compactifications with torsion that are principal two-torus bundles over a K3 surface. We consider the most general gauge bundle compatible with supersymmetry, a stable holomorphic vector bundle over the base together with an Abelian bundle over the total space, generalizing the computation previously done by the authors in the absence of the latter. Starting from a (0,2) gauged linear sigma-model with torsion we use supersymmetric localization to obtain the result. We provide also a mathematical definition of the dressed elliptic genus as a modified Euler characteristic and prove that both expressions agree for hypersurfaces in weighted projective spaces. Finally we show that it admits a natural decomposition in terms of N = 4 superconformal characters, that may be useful to investigate moonshine phenomena for this wide class of N = 2 vacua, that includes K3*T2 compactifications as special cases.
Behavior of mixed-oxide fuel elements in a tight bundle under duty-cycle conditions
International Nuclear Information System (INIS)
The irradiation behavior of the TOB-10 fuel pins was comparable with that obtained in the single pin tests. There was no significant effect that could be directly attributed to tight bundle configuration. The postirradiation examination data provided information on the axial migration of cesium and its effect on cladding strain. Severe fuel/cladding chemical interaction (FCCI), which resulted in substantial cladding thinning and probably restricted venting of fission gas from the fuel column into the pin plena, apparently caused the earlier-than-expected cladding breaches in the D9-clad pins. No such severe FCCI was noted in the 316SS-clad pins. At the time of test termination, the overall cladding strain from creep and swelling was insufficient to cause bundle closure. Consequently, there would have been minimal pin bundle-duct interaction in the subassembly. Neither of the breaches appeared to be induced by pin bundle-duct interaction. (author)
Research reactor fuel bundle design review by means of hydrodynamic testing
International Nuclear Information System (INIS)
During the design steps of a fuel bundle for a nuclear reactor, some vibration tests are usually necessary to verify the prototype dynamical response characteristics and the structural integrity. To perform these tests, the known hydrodynamic loop facilities are used to evaluate the vibrational response of the bundle under the different flow conditions that may appear in the reactor. This paper describes the tests performed on a 19 plate fuel bundle prototype designed for a low power research reactor. The tests were done in order to know the dynamical characteristics of the plates and also of the whole bundle under different flow rate conditions. The paper includes a description of the test facilities and the results obtained during the dynamical characterization tests and some preliminary comments about the tests under flowing water are also presented. (author)
Energy Band Gap Study of Semiconducting Single Walled Carbon Nanotube Bundle
Elkadi, Asmaa; Decrossas, Emmanuel; El-Ghazaly, Samir
2013-01-01
The electronic properties of multiple semiconducting single walled carbon nanotubes (s-SWCNTs) considering various distribution inside a bundle are studied. The model derived from the proposed analytical potential function of electron density for na individual s-SWCNT is general and can be easily applied to multiple nanotubes. This work demonstrates that regardless the number of carbon nanotubes, the strong coupling occurring between the closet neighbors reduces the energy band gap of the bundle by 10%. As expected, the coupling is strongly dependent on the distance separating the s-SWCNTs. In addition, based on the developed model, it is proposed to enhance this coupling effect by applying an electric field across the bundle to significantly reduce the energy band gap of the bundle by 20%.
Metallographic examination of a CANDU fuel bundle heated under severe accident conditions
International Nuclear Information System (INIS)
Post-test metallographic examination of bundle cross sections of a 19-element modified CANDU fuel bundle was carried out. The bundle, HTBS-004, had been subjected to a severe temperature excursion to 1900 degrees Celsius in superheated steam. For this study, quantitative image analysis, Auger analysis and SEM-EDX techniques were applied. A significantly large quantity of molten (Zr, U, O) alloy was relocated in the bundle section 50 mm from the upstream end, whereas the 377-mm section showed little relocated material except at the inner element junctions. These variations in the molten material generation and relocation have been correlated with the corresponding axial and radial variations in the heatup rates
Full-Scale Irradiation Test of Hanaro U3Si Fuel Using Lead Bundle
International Nuclear Information System (INIS)
To verify the irradiation performances of HANARO fuel at a nominal power of 30 MW, a lead bundle was first loaded into the HANARO core after increasing the reactor power to the full power. The lead bundle is an actual fuel assembly with 18 fuel rods that was fabricated using an atomized manufacturing procedure. The lead bundle was irradiated during 188 operation days at full power in the HANARO core, and discharged after about 60 at% average and 75 at% peak burn-ups. The maximum linear power of the lead bundle was 98kW/m. Detailed non-destructive and destructive post-irradiation tests were performed. The measured results were analyzed and compared with the existing experimental data and the design criteria for the HANARO fuel. It was confirmed that the HANARO fuel has maintained proper in-pile performances and integrity during the nominal power operation and satisfies all the design requirements related to the irradiation performances. (author)
CFD simulation of critical heat flux in a rod bundle
International Nuclear Information System (INIS)
The critical heat flux (CHF) condition is characterized by a sharp reduction of the local heat transfer coefficient which results from the replacement of liquid by vapour adjacent to the heat transfer surface. If the surface heat flux is the independent variable, the condition manifests itself as a sharp increase in surface temperature as the critical heat flux value is reached. The critical heat flux forms an important boundary for the performance of the heat exchange equipment. Determination of the critical heat flux is one of the key issues in nuclear reactor safety. This paper presents numerical simulations of boiling flow in a rod bundle with Departure from Nucleate Boiling (DNB) condition at the end of the middle rod. Large Water Loop CHF tests were used as a data set for our simulations. The Large Water Loop (LWL) is non-active pressurised-water equipment with technological and thermal parameters corresponding to those of PWR. The CHF experimental facility (a part of the Large Water Loop) has been designed for research into CHF in water flow through a bundle of electrically heated vertical rods. The critical conditions were determined under constant pressure, inlet water temperature and mass flux and for quasi steady-state - by gradually increasing the heat input. The rods are modelled by hollow tubes with direct heating of the wall. NEPTUNE-CFD code was used for numerical simulations. The computational domain covered a 30 deg. quasi-symmetric section of the actual channel. Simplified grid spacers were included in the domain. Calculations were performed with two-fluid approach with models for drag, lift, added mass and turbulent dispersion forces as well as for interfacial heat and mass transfer. Turbulent dispersion coefficient was based on void fraction gradient and on drag and mass forces. K-epsilon model was used for the prediction of the liquid turbulence, the flow of vapour was assumed to be laminar. Generalized wall heat-flux-splitting model was used
On the Geometry of the (1,1)-Tensor Bundle with Sasaki Type Metric
Institute of Scientific and Technical Information of China (English)
Arif SALIMOV; Aydin GEZER
2011-01-01
Curvature properties are studied for the Sasaki metric on the (1,1) tensor bundle of a Riemannian manifold. As an application, examples of almost para-Nordenian and para-K(a)hler-Nordenian B-metrics are constructed on the (1,1) tensor bundle by looking at the Sasaki metric. Also, with respect to the para-Nordenian B-structure, paraholomorphic conditions for the complete lifts of vector fields are analyzed.
Holding the Hunger Games Hostage at the Gym: An Evaluation of Temptation Bundling
Milkman, Katherine L.; Minson, Julia A.; Volpp, Kevin G. M.
2014-01-01
We introduce and evaluate the effectiveness of temptation bundling—a method for simultaneously tackling two types of self-control problems by harnessing consumption complementarities. We describe a field experiment measuring the impact of bundling instantly gratifying but guilt-inducing “want” experiences (enjoying page-turner audiobooks) with valuable “should” behaviors providing delayed rewards (exercising). We explore whether such bundles increase should behaviors and whether people would ...
10D massive type IIA supergravities as the uplift of parabolic M2-brane torus bundles
Energy Technology Data Exchange (ETDEWEB)
Garcia del Moral, Maria Pilar [Universidad de Antofagasta (Chile). Dept. de Fisica; Restuccia, Alvaro [Universidad de Antofagasta (Chile). Dept. de Fisica; Universidad Simon Bolivar, Caracas (Venezuela, Bolivarian Republic of). Dept. de Fisica
2016-04-15
We remark that the two 10D massive deformations of the N = 2 maximal type IIA supergravity (Romans and HLW supergravity) are associated to the low energy limit of the uplift to 10D of M2-brane torus bundles with parabolic monodromy linearly and non-linearly realized respectively. Romans supergravity corresponds to M2-brane compactified on a twice-punctured torus bundle. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Dirac method and symplectic submanifolds in the cotangent bundle of a factorizable Lie group
Capriotti, S.; Montani, H.
2011-07-01
We study some symplectic submanifolds in the cotangent bundle of a factorizable Lie group defined by second class constraints. By applying the Dirac method, we study many issues of these spaces as fundamental Dirac brackets, symmetries, and collective dynamics. As the main application, we study integrable systems on these submanifolds as inherited from a system on the whole cotangent bundle, meeting in a natural way with the Adler-Kostant-Symes theory of integrability.
Hua operator on vector bundle: Application to AdS/CFT correspondence of Dirac fields
Institute of Scientific and Technical Information of China (English)
LU; Qikeng
2005-01-01
Hua's theory of harmonic functions on classical domains is generalized to the theory on holomorphic vector bundles over classical domains and further on vector bundles over the real classical domains and quaternion classical domains. In case of the simplest quaternion classical domain there is a relation between Hua operator and Dirac operator,by which an AdS/CFT correspondence of Dirac fields is established.
The moduli space of heterotic line bundle models: a case study for the tetra-quadric
Energy Technology Data Exchange (ETDEWEB)
Buchbinder, Evgeny I. [The University of Western Australia,35 Stirling Highway, Crawley WA 6009 (Australia); Constantin, Andrei; Lukas, Andre [Rudolf Peierls Centre for Theoretical Physics, Oxford University,1 Keble Road, Oxford, OX1 3NP (United Kingdom)
2014-03-05
It has recently been realised that polystable, holomorphic sums of line bundles over smooth Calabi-Yau three-folds provide a fertile ground for heterotic model building. Large numbers of phenomenologically promising such models have been constructed for various classes of Calabi-Yau manifolds. In this paper we focus on a case study for the tetra-quadric — a Calabi-Yau hypersurface embedded in a product of four ℂℙ{sup 1} spaces. We address the question of finiteness of the class of consistent and physically viable line bundle models constructed on this manifold. Further, for a specific semi-realistic example, we explore the embedding of the line bundle sum into the larger moduli space of non-Abelian bundles, both by means of constructing specific polystable non-Abelian bundles and by turning on VEVs in the associated low-energy theory. In this context, we explore the fate of the Higgs doublets as we move in bundle moduli space. The non-Abelian compactifications thus constructed lead to SU(5) GUT models with an additional global B−L symmetry. The non-Abelian compactifications inherit many of the appealing phenomenological features of the Abelian model, such as the absence of dimension four and dimension five operators triggering fast proton decay.
Study of the end flux peaking for the Candu fuel bundle types by transport methods
International Nuclear Information System (INIS)
The region separating the Candu fuel in two adjoining bundles in a channel is called the end region. The end of the last pellet in the fuel stack adjacent to the end region is called the fuel end. In the end region of the bundle the thermal neutron flux is higher than at the axial mid-point, because the end region of the bundle is made up of very low neutron absorption material: coolant and Zircaloy-4. For accurate evaluation of fuel performance, it is important to have capability to calculate the three dimensional spatial flux distributions in the fuel bundle, including the end region. The work reported here had two objectives. First, calculation of the flux distributions (axial and radial) and the end flux peaking factors for some Candu fuel bundles. Second objective is a comparative analysis of the obtained results. The Candu fuel bundles considered in this paper are NU37 (Natural Uranium, 37 elements) and SEU43 (Slightly Enriched Uranium, 43 elements, with 1.1wt% enrichment). For realization of the proposed objectives, a methodology based on WIMS, PIJXYZ and LEGENTR codes is used in this paper. WIMS is a standard lattice-cell code, based on transport theory and it is used for producing fuel cell multigroup macroscopic cross sections. For obtaining the flux distribution in Candu fuel bundles it is used PIJXYZ and LEGENTR respectively codes. These codes are consistent with WIMS lattice-cell calculations and allow a good geometrical representation of the Candu bundle in three dimensions. PIJXYZ is a 3D integral transport code using the first collision probability method and it has been developed for Candu cell geometry. LEGENTR is a 3D SN transport code based on projectors technique and can be used for 3D cell and 3D core calculations. (author)
Cadherin-23 may be dynamic in hair bundles of the model sea anemone Nematostella vectensis.
Directory of Open Access Journals (Sweden)
Pei-Ciao Tang
Full Text Available Cadherin 23 (CDH23, a component of tip links in hair cells of vertebrate animals, is essential to mechanotransduction by hair cells in the inner ear. A homolog of CDH23 occurs in hair bundles of sea anemones. Anemone hair bundles are located on the tentacles where they detect the swimming movements of nearby prey. The anemone CDH23 is predicted to be a large polypeptide featuring a short exoplasmic C-terminal domain that is unique to sea anemones. Experimentally masking this domain with antibodies or mimicking this domain with free peptide rapidly disrupts mechanotransduction and morphology of anemone hair bundles. The loss of normal morphology is accompanied, or followed by a decrease in F-actin in stereocilia of the hair bundles. These effects were observed at very low concentrations of the reagents, 0.1-10 nM, and within minutes of exposure. The results presented herein suggest that: (1 the interaction between CDH23 and molecular partners on stereocilia of hair bundles is dynamic and; (2 the interaction is crucial for normal mechanotransduction and morphology of hair bundles.
Measurement and CFD calculation of spacer loss coefficient for a tight-lattice fuel bundle
International Nuclear Information System (INIS)
Highlights: • Experiment and CFD analysis evaluated the pressure drop in a spacer grid. • The measurement and CFD errors for the spacer loss coefficient were estimated. • The spacer loss coefficient for the dual-cooled annular fuel bundle was determined. • The CFD prediction agrees with the measured spacer loss coefficient within 8%. - Abstract: An experiment and computational fluid dynamics (CFD) analysis were performed to evaluate the pressure drop in a spacer grid for a dual-cooled annular fuel (DCAF) bundle. The DCAF bundle for the Korean optimum power reactor (OPR1000) is a 12 × 12 tight-lattice rod array with a pitch-to-diameter ratio of 1.08 owing to a larger outer diameter of the annular fuel rod. An experiment was conducted to measure the pressure drop in spacer grid for the DCAF bundle. The test bundle is a full-size 12 × 12 rod bundle with 11 spacer grid. The test condition covers a Reynolds number range of 2 × 104–2 × 105 by changing the temperature and flow rate of water. A CFD analysis was also performed to predict the pressure drop through a spacer grid using the full-size and partial bundle models. The pressure drop and loss coefficient of a spacer grid were predicted and compared with the experimental results. The CFD predictions of spacer pressure drop and loss coefficient agree with the measured values within 8%. The spacer loss coefficient for the DCAF bundle is estimated to be approximately 1.50 at a nominal operating condition of OPR1000, i.e., Re = 4 × 105
Manufacturing of 37-element fuel bundles for PHWR 540 - new approach
International Nuclear Information System (INIS)
Nuclear Fuel Complex (NFC), established in early seventies, is a major industrial unit of Department of Atomic Energy. NFC is responsible for the supply of fuel bundles to all the 220 MWe PHWRs presently in operation. For supplying fuel bundles for the forthcoming 540 MWe PHWRs, NEC is dovetailing 37-element fuel bundle manufacturing facilities in the existing plants. In tune with the philosophy of self-reliance, emphasis is given to technology upgradation, higher customer satisfaction and application of modern quality control techniques. With the experience gained over the years in manufacturing 19-element fuel bundles, NEC has introduced resistance welding of appendages on fuel tubes prior to loading of UO2 pellets, use of bio-degradable cleaning agents, simple diagnostic tools for checking the equipment condition, on line monitoring of variables, built-in process control methods and total productive maintenance concepts in the new manufacturing facility. Simple material handling systems have been contemplated for handling of the fuel bundles. This paper highlights the flow-sheet adopted for the process, design features of critical equipment and the methodology for fabricating the 37-element fuel bundles, 'RIGHT FIRST TIME'. (author)
The Moduli Space of Heterotic Line Bundle Models: a Case Study for the Tetra-Quadric
Buchbinder, Evgeny I; Lukas, Andre
2014-01-01
It has recently been realised that polystable, holomorphic sums of line bundles over smooth Calabi-Yau three-folds provide a fertile ground for heterotic model building. Large numbers of phenomenologically promising such models have been constructed for various classes of Calabi-Yau manifolds. In this paper we focus on a case study for the tetra-quadric - a Calabi-Yau hypersurface embedded in a product of four CP1 spaces. We address the question of finiteness of the class of consistent and physically viable line bundle models constructed on this manifold. Further, for a specific semi-realistic example, we explore the embedding of the line bundle sum into the larger moduli space of non-Abelian bundles, both by means of constructing specific polystable non-Abelian bundles and by turning on VEVs in the associated low-energy theory. In this context, we explore the fate of the Higgs doublets as we move in bundle moduli space. The non-Abelian compactifications thus constructed lead to SU(5) GUT models with an addit...
Performance of candu-6 fuel bundles manufactured in romania nuclear fuel plant
International Nuclear Information System (INIS)
The purpose of this article is to present the performance of nuclear fuel produced by Nuclear Fuel Plant (N.F.P.) - Pitesti during 1995 - 2012 and irradiated in units U1 and U2 from Nuclear Power Plant (N.P.P.) Cernavoda and also present the Nuclear Fuel Plant (N.F.P.) - Pitesti concern for providing technology to prevent the failure causes of fuel bundles in the reactor. This article presents Nuclear Fuel Plant (N.F.P.) - Pitesti experience on tracking performance of nuclear fuel in reactor and strategy investigation of fuel bundles notified as suspicious and / or defectives both as fuel element and fuel bundle, it analyzes the possible defects that can occur at fuel bundle or fuel element and can lead to their failure in the reactor. Implementation of modern technologies has enabled optimization of manufacturing processes and hence better quality stability of achieving components (end caps, chamfered sheath), better verification of end cap - sheath welding. These technologies were qualified by Nuclear Fuel Plant (N.F.P.) - Pitesti on automatic and Computer Numerical Control (C.N.C.) programming machines. A post-irradiation conclusive analysis which will take place later this year (2013) in Institute for Nuclear Research Pitesti (the action was initiated earlier this year by bringing a fuel bundle which has been reported defective by pool visual inspection) will provide additional information concerning potential damage causes of fuel bundles due to manufacturing processes. (authors)
Global analysis of bundle behavior in pressurized water reactor specific CORA experiments
International Nuclear Information System (INIS)
At Kernforschungszentrum Karlsruhe, out-of-pile bundle experiments are performed in the CORA facility to investigate the behavior of light water reactor fuel elements during severe fuel damage accidents. To analyze the phenomena observed during the tests, such as claddin failure, oxidation, and deformation, as well as their influence on the post test bundle state, four pressurized water reactor specific tests are selected: CORA-2, CORA-3, CORA-5, and CORA-12. From each of these tests, a detailed global analysis using all the measured temperatures, pressures, and fluid compositions as well as videoscope information has been performed. To describe the post test bundle state quantitatively, axial profiles of the bundle cross-section area, the damage state of the rods, the average cladding oxidation, and the damage to the pellets are measured. The effects of CORA-specific components on the bundle melt progression and the measured axial profiles are identified and assessed. Most of the observations during the tests as well as the post test bundle state can be explained by the established common sequence of phenomena. For a better understanding of the melt progression, some physical phenomena, such as the energy release associated with the double-sided oxidation of the cladding, the melt release, or the melt relocation, must be analyzed in detail
Heat transfer in tube bundles of heat exchangers with flow baffles induced forced mixing
International Nuclear Information System (INIS)
Thermal analysis of shell-and-tube heat exchangers is being investigated through geometric modeling of the unit configuration in addition to considering the heat transfer processes taking place within the tube bundle. The governing equations that characterize the heat transfer from the shell side fluid to the tube side fluid across the heat transfer tubewalls are indicated. The equations account for the heat transfer due to molecular conduction, turbulent thermal diffusion, and forced fluid mixing among various shell side fluid channels. The analysis, though general in principle, is being applied to the Clinch River Breeder Reactor Plant-Intermediate Heat Exchanger, which utilizes flow baffles appropriately designed for induced forced fluid mixing in the tube bundle. The results of the analysis are presented in terms of the fluid and tube wall temperature distributions of a non-baffled and baffled tube bundle geometry. The former case yields axial flow in the main bundle region while the latter is associated with axial/cross flow in the bundle. The radial components of the axial/cross flow yield the necessary fluid mixing that results in reducing the thermal unbalance among the heat transfer to the allowable limits. The effect of flow maldistribution, present on the tube or shell sides of the heat exchangers, in altering the temperature field of tube bundles is also noted
T-duality invariance, M2-brane bundles and type II classification of gauged supergravities
del Moral, Maria Pilar Garcia; Restuccia, Alvaro
2016-01-01
In this paper we obtain the eight inequivalent M2-brane symplectic torus bundles with monodromy in $SL(2,Z)$. At low energies, they correspond to the eight type II gauged supergravities in nine dimensions. Four of these class of bundles are directly obtained by means of the sculpting mechanism of the supermembrane (M2-brane) compactified on $M_9\\times T^2$. The other inequivalent four ones were originally inferred from the fact that T-duality for the supermembrane is a symmetry of the theory. In this paper we deep on the T-duality action on the supermembrane bundle description. We obtain the most general expression for the supermembrane T-duality transformation. The T-duality acts not only at the level of the mass operator but also topologically on the geometrical bundle structure of the theory. For a given monodromy class of the M2-brane torus bundle, T-duality acts non-trivially on its coinvariant classes. We provide the precise T-duality relation between the M2-brane bundles. The allowed gauging groups at ...
[Philo of Alexandria and his views on health and sickness].
Kaiser, Otto
2015-01-01
Philo of Alexandria, Torah scholar and philosopher of religion, (c. 20 BC to 50 BCE) is the first Middle Platonic philosopher whom we know through his own works. His thinking was determined by the two antitheses of God and world, and virtue and vice. The Logos (divine reason) mediates between the transcendent God and the earthly world. His thoughts on health and illness and on the possibilities and limitations of medicine are testimony to his comprehensive philosophical education as well as to his belief in God as ruler of the world and of human life. He saw human health as the reward for self-control for which one was best prepared by the classical education programme. Self-control and physical exercise were therefore, in his view, possible guarantors of health, and a coach potentially more important than a physician. Illnesses, if they result from the loss of self-control, may point to the necessity for penitence. Philo therefore saw virtuousness as the safest precondition for a healthy and cheerful life. That the life forces increase during youth and diminish in old age is part of destiny. Similarly, illness can be brought about by strokes of fate. If illness occurred in this or any other way, medicine was there to help and its success or failure depended on divine providence. Like Jesus Sirach, the Jewish scholar who taught around a hundred years earlier, Philo did not think it sinful to use medical help if one was ill, seeing that God himself had made natural remedies available. He compared the importance of physicians for their patients to that other professionals have in people's lives. Philo did not provide a compendium on the work of the physician, but he gave indications, on nutrition for instance, or on the use of laxatives and fragrances, or that complaints can be necessary stages of recovery. Philo also asked himself whether physicians were always obliged to tell patients the truth. The only case of illness he described in sufficient detail was one of
Holomorphic Vector Bundles Corresponding to some Soliton Solutions of the Ward Equation
International Nuclear Information System (INIS)
Holomorphic vector bundles corresponding to the static soliton solution of the Ward equation were explicitly presented by Ward in terms of a meromorphic framing. Bundles (for simplicity, “bundle” is to be taken throughout to mean “holomorphic vector bundle”) corresponding to all Ward k-soliton solutions whose extended solutions have only simple poles, and some Ward 2-soliton solutions whose extended solutions have only a second-order pole, were explicitly described by us in a previous paper. In this paper, we go on to present some bundles corresponding to soliton-antisoliton solutions of the Ward equation, and Ward 3-soliton solutions whose extended solutions have a simple pole and a double pole. To give some more interpretation of the bundles, we study the second Chern number of the corresponded bundles and find that it can be obtained directly from the patching matrices. We also point out some information about bundles corresponding to Ward soliton solutions whose extended solutions have general pole data at the end of the paper
Holomorphic Vector Bundles Corresponding to some Soliton Solutions of the Ward Equation
Energy Technology Data Exchange (ETDEWEB)
Zhu, Xiujuan, E-mail: yzzhuxiujuan@sina.com [Jiangsu Second Normal University, School of Mathematics and Information Technology (China)
2015-12-15
Holomorphic vector bundles corresponding to the static soliton solution of the Ward equation were explicitly presented by Ward in terms of a meromorphic framing. Bundles (for simplicity, “bundle” is to be taken throughout to mean “holomorphic vector bundle”) corresponding to all Ward k-soliton solutions whose extended solutions have only simple poles, and some Ward 2-soliton solutions whose extended solutions have only a second-order pole, were explicitly described by us in a previous paper. In this paper, we go on to present some bundles corresponding to soliton-antisoliton solutions of the Ward equation, and Ward 3-soliton solutions whose extended solutions have a simple pole and a double pole. To give some more interpretation of the bundles, we study the second Chern number of the corresponded bundles and find that it can be obtained directly from the patching matrices. We also point out some information about bundles corresponding to Ward soliton solutions whose extended solutions have general pole data at the end of the paper.
Antonio Gramsci and his relevance for the education of adults
Mayo, Peter
2008-01-01
This paper, drawing on original sources, provides an overview of and a discussion on those writings and ideas, in Antonio Gramsci's huge corpus of work, that are relevant to the education of adults. This should provide a fitting tribute to this major social theorist of the 20th century on the 70th anniversary of his death. Among the topics discussed are those of adult education for industrial democracy, adult education and cultural preparation, adult literacy, prison education, adult educatio...
Fabrication of a CANFLEX-RU designed bundle for power ramp irradiation test in NRU
International Nuclear Information System (INIS)
The BDL-443 CANFLEX-RU bundle AKW was fabricated at Korea Atomic Energy Research Institute (KAERI) for power ramp irradiation testing in NRU reactor. The bundle was fabricated with IDR and ADU fuel pellets in adjacent elements and contains fuel pellets enriched to 1.65 wt% 235U in the outer and intermediate rings and also contains pellets enriched to 2.00 wt% 235U in the inner ring. This bundle does not have a center element to allow for insertion on a hanger bar. KAERI produced the IDR pellets with the IDR-source UO2 powder supplied by BNFL. ADU pellets were fabricated and supplied by AECL. Bundle kits (Zircaloy-4 end plates, end plugs, and sheaths with brazed appendages) manufactured at KAERI earlier in 1996 were used for the fabrication of the bundle. The CANFLEX bundle was fabricated successfully at KAERI according to the QA provisions specified in references and as per relevant KAERI drawings and technical specification. This report covers the fabrication activities performed at KAERI. Fabrication processes performed at AECL will be documented in a separate report
[Johannes de Laet and his vision of the New World].
Vannini de Gerulewicz, M
1992-06-01
Highlighting the contribution of Johannes De Laet (1582-1649), naturalist, historian, researcher, to the knowledge of the New World history and geography, as well as its inhabitants, flora and fauna. Laet published his huge New World or Description of the Occidental Indies in Dutch (1625), Latin (1633) and French (1640). The first Spanish edition appeared in 1988 in Venezuela, edited by the author of this work. PMID:11636366
[J.E. GILIBERT--HIS LIFE AND WORK IN THE LIGHT OF A CORRESPONDENCE AND TESTIMONIES OF HIS TIME].
Daszkiewicz, Piotr
2015-01-01
Jean-Emmanuel Gilibert (1741-1814) has been the subject of few biographical works. This paper presents the results of research from unpublished documents, unknown by historians until now. The information, publishedin old sources as in Gilibert autobiographical sketches or in catalogues of natural history papers auctions, is critically analyzed here. We also tried to establish a list of documents from those cited by Gilibert biographers, but lost today. The author both presents and comments letters to Antoine-Laurent de Jussieu (1748-1836) and André Thouin (1747-1824), as well as a letter to an unknown receiver, in the autograph's collection of Gustave Thuret (1747-1824) and Eduard Bornet (1828-1911)--which is conserved in the collection of the National Museum of Natural History in Paris. Precious information about Gilibert and his stay in Lithuania was found in the letters of Antoine Gouan (1733-1821) to Philippe-Isidore Picot de Lapeyrouse (1744-1818). Research were also conducted in the Museum's herbarium in order to find Gilibert's specimens from Lithuania as well as to discover more information about the naturalist himself. The documents of Jean Hermann (1738-1800) linked with Gilibert were found in Strasbourg's National and University Libraries and in the Municipal Archives; a letter from Gilibert to Antoine-Laurent de Jussieu was also discovered in this collection. Some new and interesting data came from a register of Hermann's natural history cabinet visitors Some additional information about Gilibert's life and work was obtained as a result of the analysis of manuscripts conserved in the National Academy of Medicine in Paris, more specifically in Gilibert's correspondences from Lithuania and Lyon about illnesses and epidemics. The information obtained allowed a better knowledge of the history of Gilibert floristic works in Lithuania, his zoological research, his practice of medicine and his study of different pathologies, his way of collecting and the
A Piecewise Hysteresis Model for a Damper of HIS System
Directory of Open Access Journals (Sweden)
Kaidong Tian
2016-01-01
Full Text Available A damper of the hydraulically interconnected suspension (HIS system, as a quarter HIS, is prototyped and its damping characteristic is tested to characterize the damping property. The force-velocity characteristic of the prototype is analyzed based on a set of testing results and accordingly a piecewise hysteresis model for the damper is proposed. The proposed equivalent parametric model consists of two parts: hysteresis model in low speed region and saturation model in high speed region which are used to describe the hysteresis phenomenon in low speed and nonhysteresis phenomenon in high speed, respectively. The parameters of the model are identified based on genetic algorithm by setting the constraints of parameters according to their physical significances and the corresponding testing results. The advantages of the model are highlighted by comparing to the nonhysteresis model and the permanent hysteresis model. The numerical simulation results are compared with the testing results to validate the accuracy and effectiveness of the proposed model. Finally, to further verify the proposed model’s wide applicability under different excitation conditions, its results are compared to the testing results in three-dimensional space. The research in this paper is significant for the dynamic analysis of the HIS vehicle.
International Nuclear Information System (INIS)
The development of the fast reactor cycle is being preceded in Japan to utilize plutonium and trans-uranium materials which come from the simplified PUREX reprocessing. But the TRU fuel bundle generates heat due to fission of TRU during the fabrication process of the wire wrapped Fast Breeder Reactor (FBR) fuel pin bundle. Then it is a big issue to develop an efficient cooling system for the horizontally laid bundle and to clarify its thermal behavior. Then in this paper the steady state full mock up test results are described. Inlet air velocity and heat generation rate were varied in the tests as the parameter. Then it is ascertained that the fuel can be cooled under the 473 K which is the criterion for the steady state cooling of this study to keep cladding soundness. The temperature and velocity fields of the bundle upper side were also measured by moving thermocouples to vertical and horizontal directions, by the infrared thermometer and by PIV (Particle Image Velocimetry). Then the temperature and velocity fields at outlet region are clarified. (author)
Boller, François; Bogousslavsky, Julien
2015-01-01
Reports of postamputation pain and problems linked to phantom limbs have increased in recent years, particularly in relation to war-related amputations. These problems are still poorly understood and are considered rather mysterious, and they are difficult to treat. In addition, they may shed light on brain physiology and neuropsychology. Functional neuroimaging techniques now enable us to better understand their pathophysiology and to consider new rehabilitation techniques. Several artists have suffered from postamputation complications and this has influenced not only their personal life but also their artistic work. Paul Wittgenstein (1887-1961), a pianist whose right arm was amputated during the First World War, became a famous left-handed concert performer. His case provides insight into Post-World War I musical and political history. More specifically, the impact on the artistic life of this pianist illustrates various postamputation complications, such as phantom limb, stump pain, and especially moving phantom. The phantom movements of his right hand helped him develop the dexterity of his left hand. Wittgenstein played piano works that were written especially for him (the most famous being Ravel's Concerto for the Left Hand) and composed some of his own. Additionally, several famous composers had previously written for the left hand. PMID:25684295
T-duality for circle bundles via noncommutative geometry
Mathai, Varghese
2013-01-01
Recently Baraglia showed how topological T-duality can be extended to apply not only to principal circle bundles, but also to non-principal circle bundles. We show that his results can also be recovered via two other methods: the homotopy-theoretic approach of Bunke and Schick, and the noncommutative geometry approach which we previously used for principal torus bundles. This work has several interesting byproducts, including a study of the K-theory of crossed products by Isom(R), the universal cover of O(2), and some interesting facts about equivariant K-theory for Z/2. In the final section of this paper, these results are extended to the case of bundles with singular fibers, or in other words, non-free O(2)-actions.
International Nuclear Information System (INIS)
Full text: For reprocessing of PHWR fuel, fuel bundles are at present chopped mechanically into small pieces of pins using high tonnage mechanical press before dissolution. The existing method of bundle dismantling is purely mechanical using very high force for chopping. A laser based automated bundle dismantling system is developed. In the system, end-plates of bundle, which holds the fuel pins together, are cut using Nd-YAG laser to separate the bundles into pins. In addition to pin separation, the pins are to be chopped into small pieces using a small mechanical chopper. Since the spent fuel is highly radioactive, all these operations are performed remotely in hot cells. Post irradiation examination also requires dismantling of bundles into pins so that they can select the pins for the further examinations. In both these applications laser dismantling remains the most. important step and this system has been developed and tested. This paper describes the experience gained during the development efforts
Lim, Hong-Chul; Yoon, Yong-Cheol; Wang, Joon-Ho; Bae, Ji-Hoon
2012-01-01
Background The purpose of this study was to compare the initial stability of anatomical and non-anatomical single bundle anterior cruciate ligament (ACL) reconstruction and to determine which would better restore intact knee kinematics. Our hypothesis was that the initial stability of anatomical single bundle ACL reconstruction would be superior to that of non-anatomical single bundle ACL reconstruction. Methods Anterior tibial translation (ATT) and internal rotation of the tibia were measure...
Visual observations of a degraded bundle of irradiated fuel: the Phebus FPT1 test
International Nuclear Information System (INIS)
The international Phebus-FP (Fission Product) project is managed by the Institut de Protection et Surete Nucleaire in collaboration with Electricite de France (EDF), the European Commission (EC), the USNRC (USA), COG (Canada), NUPEC and JAERI (Japan), KAERI (South Korea), PSI and HSK (Switzerland). It is designed to measure the source-term and to study the degradation of irradiated UO2 fuel in conditions typical of a severe loss of coolant accident in a pressurised water reactor (PWR). In the first test (FPT0), performed in December '93, a bundle of 20 fresh fuel rods and a central Ag-In-Cd control rod underwent a short 15-day irradiation to generate fission products before testing in the Phebus reactor in Cadarache. The second test (FPT1) was performed in July '96, in the same conditions and geometry, but using irradiated fuel (-23 GWd/tU). In the FPT1 test, the bundle was heated to an estimated 3000 K over a period of 30 minutes in order to induce a substantial liquefaction of the bundle. After the test, the bundle was embedded in epoxy and cut at different levels to investigate the mechanisms of the core degradation. This paper reports the visual observations of the degraded FPT1 bundle, very preliminary interpretations about the scenario of degradation and a comparison between the behaviour of the fuel in the FPT0 and FPT1 tests. (author)
Assessment of the influence of subchannel analysis model on the prediction of CHF in rod bundles
International Nuclear Information System (INIS)
The influence of the turbulent mixing model employed in a subchannel analysis code was investigated in this study, especially on the prediction of the critical heat flux (CHF) in rod bundles. The equal-volume-exchange turbulent mixing and void drift model was employed in the MATRA code, and the void drift coefficient was optimized through the analysis of two-phase flow distribution data for GE 9-rod and Ispra 16-rod test bundles. The influence of the subchannel analysis model on the analysis of CHF was examined by evaluating the CHF test data in rod bundles representing PWR and BWR conditions. The CHFR margin of typical LWR cores was evaluated by taking into account the influence on the local parameter CHF correlation and the hot channel analysis result. As the result, it appeared that the turbulent mixing model has an important effect on the prediction of CHF under the low pressure and the closed-assembly-channel conditions
International Nuclear Information System (INIS)
Highlights: • Thermal–hydraulic performance of a non-circular tube bundle has been investigated experimentally. • Tubes were mounted in staggered arrangement with two longitudinal pitch ratios 1.5 and 2. • Drag coefficient and Nusselt number of tubes in second row was measured. • Friction factor of this tube bundle is lower than circular tube bundle. • Thermal–hydraulic performance of this tube bundle is greater than circular tube bundle. - Abstract: Flow and heat transfer from cam-shaped tube bank in staggered arrangement is studied experimentally. Tubes were located in test section of an open loop wind tunnel with two longitudinal pitch ratios 1.5 and 2. Reynolds number varies in range of 27,000 ⩽ ReD ⩽ 42,500 and tubes surface temperature is between 78 and 85 °C. Results show that both drag coefficient and Nusselt number depends on position of tube in tube bank and Reynolds number. Tubes in the first column have maximum value of drag coefficient, while its Nusselt number is minimum compared to other tubes in tube bank. Moreover, pressure drop from this tube bank is about 92–93% lower than circular tube bank and as a result thermal–hydraulic performance of this tube bank is about 6 times greater than circular tube bank
Theoretical calculations of thermophysical properties of single-wall carbon nanotube bundles
International Nuclear Information System (INIS)
Carbon nanotube bundles are promising thermal interfacial materials due to their excellent thermal and mechanical characteristics. In this study, the phonon dispersion relations and density of states of the single-wall carbon nanotube bundles are calculated by using the force constant model. The calculation results show that the inter-tube interaction leads to a significant frequency raise of the low frequency modes. To verify the applied calculation method, the specific heat of a single single-wall carbon nanotube is calculated first based on the obtained phonon dispersion relations and the results coincide well with the experimental data. Moreover, the specific heat of the bundles is calculated and exhibits a slight reduction at low temperatures in comparison with that of the single tube. The thermal conductivity of the bundles at low temperatures is calculated by using the ballistic transport model. The calculation results indicate that the inter-tube interaction, i.e. van der Waals interaction, hinders heat transfer and cannot be neglected at extremely low temperatures. For (5, 5) bundles, the relative difference of the thermal conductivity caused by ignoring inter-tube effect reaches the maximum value of 26% around 17 K, which indicates the significant inter-tube interaction effect on the thermal conductivity at low temperatures. (condensed matter: structural, mechanical, and thermal properties)
Theoretical calculations of thermophysical properties of single-wall carbon nanotube bundles
Institute of Scientific and Technical Information of China (English)
Miao Ting-Ting; Song Meng-Xuan; Ma Wei-Gang; Zhang Xing
2011-01-01
Carbon nanotube bundles are promising thermal interfacial materials due to their excellent thermal and mechanical characteristics. In this study, the phonon dispersion relations and density of states of the single-wall carbon nanotube bundles are calculated by using the force constant model. The calculation results show that the inter-tube interaction leads to a significant frequency raise of the low frequency modes. To verify the applied calculation method, the specific heat of a single single-wall carbon nanotube is calculated first based on the obtained phonon dispersion relations and the results coincide well with the experimental data. Moreover, the specific heat of the bundles is calculated and exhibits a slight reduction at low temperatures in comparison with that of the single tube. The thermal conductivity of the bundles at low temperatures is calculated by using the ballistic transport model. The calculation results indicate that the inter-tube interaction, i.e. van der Waals interaction, hinders heat transfer and cannot be neglected at extremely low temperatures. For (5, 5) bundles, the relative difference of the thermal conductivity caused by ignoring inter-tube effect reaches the maximum value of 26% around 17 K, which indicates the significant inter-tube interaction effect on the thermal conductivity at low temperatures.
Directory of Open Access Journals (Sweden)
V. B. Kuntysh
2014-01-01
Full Text Available The paper presents a scheme and description of a new aerodynamic stand that has a 300x300 mm cross-section operating channel. The stand is used for studying thermal and aerodynamic characteristics of bundles made of finned tubes of actual dimensions in crossflow. The paper provides results of an exploratory test pertaining to heat transfer and resistance of four row staggered bundle made of tubes with aluminium spiral fins having outside diameter of 26 mm which are used in the systems of ventilation, air-conditioning and heating of buildings and also in transport heat exchangers.
Energy Technology Data Exchange (ETDEWEB)
R Acharya; V Carnevale; G Fiorin; B Levine; A Polishchuk; V Balannick; I Samish; R Lamb; L Pinto; et al.
2011-12-31
The M2 proton channel from influenza A virus is an essential protein that mediates transport of protons across the viral envelope. This protein has a single transmembrane helix, which tetramerizes into the active channel. At the heart of the conduction mechanism is the exchange of protons between the His37 imidazole moieties of M2 and waters confined to the M2 bundle interior. Protons are conducted as the total charge of the four His37 side chains passes through 2{sup +} and 3{sup +} with a pK{sub a} near 6. A 1.65 {angstrom} resolution X-ray structure of the transmembrane protein (residues 25-46), crystallized at pH 6.5, reveals a pore that is lined by alternating layers of sidechains and well-ordered water clusters, which offer a pathway for proton conduction. The His37 residues form a box-like structure, bounded on either side by water clusters with well-ordered oxygen atoms at close distance. The conformation of the protein, which is intermediate between structures previously solved at higher and lower pH, suggests a mechanism by which conformational changes might facilitate asymmetric diffusion through the channel in the presence of a proton gradient. Moreover, protons diffusing through the channel need not be localized to a single His37 imidazole, but instead may be delocalized over the entire His-box and associated water clusters. Thus, the new crystal structure provides a possible unification of the discrete site versus continuum conduction models.
International Nuclear Information System (INIS)
This paper describes works on CANDU fuel bundle fabrication in the Fuel Fabrication Development and Testing Section (FFDT) of AECL's Chalk River Laboratories. This work does not cover fuel design, pellet manufacturing, Zircaloy material manufacturing, but cover the joining of appendages to sheath tube, endcap preparation and welding, UO2 loading, end plate preparation and welding, and all inspections required in these steps. Materials used in the fabrication of CANDU fuel bundle are: 1)Ceramic UO2 Pellet 2)Zircaloy -4. Fuel Bundle Structural Material 3) Others (Zinc stearate, Colloidal graphite, Beryllium and Heium). Th fabrication of fuel element consist of three process: 1)pellet loading into the sheats, 2) endcap welding, and 3) the element profiling. Endcap welds is tested by metallography and He leak test. The endcaps of the elements are welded to the end plates to form the 37- element bundle assembly
The Business of Bundling: Joining Forces on Joint Replacement.
Kaldy, Joanne
2016-01-01
A mandated bundled-payment program for joint replacement is in place in several regions across the country, and practitioners such as pharmacists are still sorting out their roles in this federal initiative. To get involved, pharmacists need to establish connections with area hospitals and physician groups to promote and document their ability to manage medications, reduce and eliminate medication-related problems and rehospitalizations, and work with patients to maximize adherence and improve communication for those undergoing hip and knee replacement. PMID:26975592
Study on galloping behavior of iced eight bundle conductor transmission lines
Zhou, Linshu; Yan, Bo; Zhang, Liang; Zhou, Song
2016-02-01
Wind tunnel test was carried out to obtain the aerodynamic coefficients of an eight bundle conductor accreted with crescent-shaped ice. A user-defined cable element with torsional degree of freedom is developed in ABAQUS software to capture the torsional deformation of the iced conductors during galloping. By means of the user-defined cable element, different damping ratios in in-plane, out-of-plane and torsional directions of the conductors can be defined and the aerodynamic forces varying with their motion status can be exerted on the conductors conveniently when ABAQUS is used to simulate galloping of transmission lines. A wind tunnel test to model galloping of an iced eight bundle conductor segment was carried out, and the validity of the numerical simulation method is demonstrated by the agreement of the galloping orbit of the bundle conductor segment model recorded in the test and that by the numerical simulation. Furthermore, galloping behavior, including dynamic responses, galloping orbits, frequencies, vibration modes and amplitudes, of typical iced eight bundle conductor transmission lines in the cases of different span lengths, initial tensions in sub-conductors, wind velocities, angles of wind attack and damping ratios is studied, and the galloping behavior of the lines with internal resonance conditions is discussed. The obtained results may provide a fundamental tool for the development of anti-galloping techniques of eight bundle conductor transmission lines.
Energy Technology Data Exchange (ETDEWEB)
Seo, Jeong Sik; Kim, Kyoung Rock; Choi, Young Don [Korea Univ., Seoul (Korea, Republic of); Shin, Jong Keun [Hanzhong Univ., Donghae (Korea, Republic of)
2008-07-01
This paper is described for the measurement technique for local heat transfer coefficients using a copper sensor in rod bundles with mixing vanes. A copper sensor is defined as the device to measure the convective heat transfer coefficient using constant heat flux and surface temperatures. The copper sensor consists of a cartridge heater and four pieces of thermocouple. The copper sensors located at axial positions of rod bundles are able to measure the local heat transfer coefficients at its positions. The effect of local heated and full heated of copper sensors for rod bundles is investigated using CFD analysis. The decay of local heat transfer coefficients of locally heating condition such as a copper sensor is estimated to be higher value than that of fully heating condition. The calibration curve for local heat transfer coefficients measured is presented.
An experimental study of water distribution from a jet to a single pin and pin bundles
International Nuclear Information System (INIS)
A knowledge of the water distribution in spray cooling of overheated water reactor fuel bundles is necessary for the proper analysis of heat removal under accident conditions. Results are presented of experiments on the distribution of water from a single horizontal jet to a cold vertical pin and both heated and unheated pin bundles. The flow running down a single cold pin has been determined for a range of jet impact angles, jet flow rates, and jet diameters. This is a critical flowrate above which water detaches from the pin at normal impact and it has been shown that at this critical flowrate the fraction of water flowing down the pin is proportional to the cosine of the impact angle. Tests with a cold six-pin sector of a three-ringed 36 pin bundle showed that distribution of water to the pins was non-uniform and sensitive to both jet orientation and velocity, as may be expected from the single pin results. Experiments on a hot six-pin showed that individual pins quenched at a rate predictable from cold six-pin flow distribution tests and a hot single pin 'calibration' test, once wetting was fully established at the water injection level. Observations made in a 36 pin heated bundle with six water jets confirmed the findings on the smaller bundles. It has also been shown that during delays in the establishment of wetting, the water distribution will be markedly different to that once wetting is established. (author)
Prediction of void fraction in a subchannel and bundle geometry with FLICA4 and TRACE
International Nuclear Information System (INIS)
In order to encourage advancement in subchannel analyses of fluid flow in rod bundles, an international benchmark program, namely the OECD/NRC PWR Subchannel and Bundle Test (PSBT) benchmark, has been organized. The PSBT benchmark aims at assessing the capabilities of subchannel analysis codes, system codes, and computational fluid dynamics (CFD) codes for the prediction of detailed void distributions in subchannels, including departure from nucleate boiling, on the basis of experimental data measured at a full scale prototypical PWR rod bundle. Within the framework of the PSBT benchmark, analyses of the void distribution in a subchannel and bundle geometry have been performed at the Paul Scherrer Institut by means of the subchannel analysis code FLICA4, and the thermal-hydraulic system code TRACE. Steady-state scenarios are analyzed by using both FLICA4 and TRACE and transient analyses are performed with FLICA4. In particular, the TRACE calculations for bundle geometry have been carried out employing a three-dimensional vessel component to model cross flows between subchannels. The analysis aims at evaluating the applicability of a three-dimensional vessel component of TRACE for subchannel analyses, as well as validating the subchannel code FLICA4. The calculated void fractions are compared to the experimental data, and the accuracies of the predictions by both codes are appraised by means of a statistical analysis. (author)
Jean Piaget: Images of a life and his factory.
Burman, Jeremy Trevelyan
2012-08-01
In this article, I use a new book about Jean Piaget to introduce a new historical method: examining "psychological factories." I also discuss some of the ways that "Great Men" are presented in the literature, as well as opportunities for new projects if one approaches the history of the discipline differently and examines the conditions that made that greatness possible. To that end, the article includes many details about Piaget that have never before been discussed in English. Attention is drawn, in particular, to Piaget's collaborators: the hundreds of workers at his factory in Geneva, many of whom were women. (PsycINFO Database Record (c) 2012 APA, all rights reserved). PMID:23397918
Posttest examination of the VVER-1000 fuel rod bundle CORA-W2
International Nuclear Information System (INIS)
The bundle meltdown experiment CORA-W2, representing the behavior of a Russian type VVER-1000 fuel element, with one B4C/stainless steel absorber rod was selected by the OECD/CSNI as International Standard Problem (ISP-36). The experimental results of CORA-W2 serve as data base for comparison with analytical predictions of the high-temperature material behavior by various code systems. The first part of the experimental results is described in KfK 5363 (1994), the second part is documented in this report which contains the destructive post-test examination results. The metallographical and analytical (SEM/EDX) post-test examinations were performed in Germany and Russia and are summarized in five individual contributions. The upper half of the bundle is completely oxidized, the lower half has kept the fuel rods relatively intact. The post-test examination results show the strong impact of the B4C absorber rod and the stainless steel grid spacers on the ''low-temperature'' bundle damage initiation and progression. The B4C absorber rod completely disappeared in the upper half of the bundle. The multicomponent melts relocated and formed coolant channel blockages on solidification with a maximum extent of about 30% in the lower part of the bundle. At temperatures above the melting point of the ZrNb1 cladding extensive fuel dissolution occurred. (orig.)
Manca, Fabio; Giordano, Stefano; Palla, Pier Luca; Cleri, Fabrizio
2015-05-01
The mechanics of fiber bundles has been largely investigated in order to understand their complex failure modes. Under a mechanical load, the fibers fail progressively while the load is redistributed among the unbroken fibers. The classical fiber bundle model captures the most important features of this rupture process. On the other hand, the homogenization techniques are able to evaluate the stiffness degradation of bulk solids with a given population of cracks. However, these approaches are inadequate to determine the effective response of a degraded bundle where breaks are induced by non-mechanical actions. Here, we propose a method to analyze the behavior of a fiber bundle, undergoing a random distribution of breaks, by considering the intrinsic response of the fibers and the visco-elastic interactions among them. We obtain analytical solutions for simple configurations, while the most general cases are studied by Monte Carlo simulations. We find that the degradation of the effective bundle stiffness can be described by two scaling regimes: a first exponential regime for a low density of breaks, followed by a power-law regime at increasingly higher break density. For both regimes, we find analytical effective expressions described by specific scaling exponents. PMID:25998172
International Nuclear Information System (INIS)
The CANFLEX1 bundle is being developed jointly by AECL and KAERI as a vehicle for introducing the use of enrichment and advanced fuel cycles in CANDU2 reactors. The bundle design uses smaller diameter fuel elements in the outer ring of a 43-element bundle to reduce the maximum element ratings in a CANDU fuel bundle by 20% compared to the 37-element bundle currently in use. This facilitates burnups of greater than 21,000 MW d/TAU to optimize the economic benefit available from the use of enrichment and advanced fuel cycles. A combination of this lower fuel rating, plus development work underway at Aecl to enhance the thermalhydraulic characteristics of the bundle (including both CHF3 and bundle. This provides extra flexibility in the fuel management procedures required for fuel bundles with higher fissile contents. The different bundle geometry requires flow tests to demonstrate acceptable vibration and fretting behavior of the Conflux bundle. A program to undertake the necessary range of flow tests has started at KAERI, involving the fabrication of the required bundles, and setting up for the actual tests. A program to study the fuel management requirements for slightly enriched (0.9 wt % 235 in total U) Conflux fuel has been undertaken by both Aecl and KAERI staff, and further work has started for higher enrichments. Irradiation testing of the Conflux bundle started in the NUR reactor in 1989, and a second irradiation test is due to start shortly. This paper describes the program, and reviews the status of key parts of the program
Sarukhanyan, Edita; De Nicola, Antonio; Roccatano, Danilo; Kawakatsu, Toshihiro; Milano, Giuseppe
2014-03-01
The processes of CNTs bundle formation and insertion/rearrangement inside lipid bilayers, as models of cellular membranes, is described and analyzed in details using simulations on the microsecond scale. Molecular Dynamics simulations employing hybrid particle-field models (MD-SCF) show that during the insertion process lipid molecules coat bundles surfaces. The distortions of bilayers are more pronounced for systems undergoing to insertion of bundles made of longer CNTs. In particular, when the insertion occurs in perpendicular orientation, adsorption of lipids on CNTs surfaces promotes a transient poration. This result suggests mechanism of membrane disruption operated by bundles causing the formation of solvent-rich pockets.
Simulations of resonant Raman response in bundles of semiconductor carbon nanotubes
Roslyak, Oleksiy; Piryatinski, Andrei; Doorn, Stephen; Haroz, Erik; Telg, Hagen; Duque, Juan; Crochet, Jared; Simpson, J. R.; Hight Walker, A. R.; LANL Collaboration; Fordham Collaboration; NIST Collaboration
This work is motivated by an experimental study of resonant Raman spectroscopy under E22 excitation, which shows a new, sharp feature associated with bundling in (6,5) semiconductor carbon nanotubes. In order to provide an insight into the experimental data, we model Raman excitation spectra using our modified discrete dipole approximation (DDA) method. The calculations account for the exciton states polarized along and across the nanotube axis that are characterized by a small energy splitting. Strong polarization of the nanotubes forming the bundle results in the exciton state mixing whose spectroscopic signatures such as peaks positions, line widths, and depolarization ratio are calculated and compared to the experiment. Furthermore, the effects of the energy and structural disorder, as well as structural defects within the bundle are also examined and compared with the experimental data.
Criteria for the onset of mixed convection and onset of recirculation in vertical rod bundles
International Nuclear Information System (INIS)
Criteria were developed for the onset of recirculation and onset of mixed convection in vertical rod bundles. It was concluded that the dominant mechanisms governing mixed convection in rod bundles are the frictional and buoyancy forces. By balancing these two terms, the key dimensionless parameters were identified as Re and B*. The criteria was expressed in terms of a flow regime map of Re versus B*. It was found that the onset of mixed convection could be predicted with forced convection input parameters, but for the onset of recirculation the effect of buoyancy on mixing was important
Park, Sang Eun; Ko, Yujin
2013-01-01
Surgical reconstruction is a general approach for an anterior cruciate ligament rupture. Techniques have evolved from single-bundle to double-bundle reconstruction to restore the 2 anatomically and functionally different bundles as much as possible. However, there is controversy regarding which method yields superior clinical outcomes. The purpose of this article is to introduce our new graft preparation method, which will potentially address the limitations of currently available double-bund...
Safety analysis report of the irradiation test of Type-B bundle
Energy Technology Data Exchange (ETDEWEB)
Lee, Choong Sung; Lim, I. C.; Lee, B. C.; Ryu, J. S.; Kim, H. R
2000-06-01
The HANARO fuel, U{sub 3}Si-A1, has been developed by AECL and tested in NRU reactor. In the course of the fuel qualification tests, only one case was performed under the higher power condition than maximum linear power which was expected in the design stage. The Korea regulatory body, KINS imposed that HANARO shall be operated at the power level less than 24MW which is 80% of the design full power until HANARO shows the repetitive performance of the fuel at the power condition abov e 112.8KW/m. To resolve this imposition, KAERI designed two types of special test bundles: two non-instrumented(Type-A) and one instrumented(Type-B) test bundles. Two Type-A bundles were irradiated in HANARO: one of them has finished PIE and the other is under PIE. Type-B bundle was loaded in the core during 1.32 day at 1996, but outstanding FIV(flow induced vibration) was observed at the pool top because of long guide tube attached to the top of the bundle. The successful installation of the chimney fastener to fix the guide tube resulted in conducting the irradiation test of Type-B bundle again. The test will start at mid- July, 2000. In order to safely do the Type-B irradiation test, the safety analysis for the nuclear, mechanical and thermal-hydraulic aspects was performed. The reactivity worth and the maximum 1 near power predicted by VENTURE are 6.3mk/k and 121.6kW/m, respectively. Thermal margins for normal and transient conditions using MATRA-h, are assessed to satisfy the safety criteria.
Does size matter? : disentangling consumers' bundling preferences
Manoj K. Agarwal; Frambach, Ruud T.; Stremersch, Stefan
2000-01-01
Previous marketing literature has focused to a large extent on the effect of bundle characteristics on a consumer’s decision to buy a (fixed) bundle in a non-competitive setting. This study extends this narrow focus in four major ways. First, the authors address bundles that are customizable. Second, they distinguish between a consumer’s decision of whether to bundle (bundle choice) and the decision of how many goods or services to include in a bundle (bundle size). Third, they extend the foc...
Energy Technology Data Exchange (ETDEWEB)
Doebner, H.; Mann, H. [Arnold Sommerfeld Institute for Mathematical Physics, Technical University of Clausthal, 38678 Clausthal-Zellerfeld (Germany)
1997-08-01
We consider configuration spaces of nonidentical pointlike particles. The physically motivated assumption that any two particles cannot be located at the same point in space{endash}time leads to nontrivial topological structure of the configuration space. For a quantum mechanical description of such a system, we classify complex vector bundles over the configuration space and obtain potentials of topological origin, similar to those that occur in the fiber bundle approach to Dirac{close_quote}s magnetic monopole or in Yang{endash}Mills theory. {copyright} {ital 1997 American Institute of Physics.}
The Picard group of the moduli of G-bundles on a curve
Beauville, Arnaud; Laszlo, Yves; Sorger, Christoph
1996-01-01
Let G be a complex semi-simple group, and X a compact Riemann surface. The moduli space of principal G-bundles on X, and in particular the holomorphic line bundles on this space and their global sections, play an important role in the recent applications of Conformal Field Theory to algebraic geometry. In this paper we determine the Picard group of this moduli space when G is of classical or G_2 type (we consider both the coarse moduli space and the moduli stack).
The many faces of Maxwell, Dirac and Einstein equations a Clifford bundle approach
Rodrigues, Jr, Waldyr A
2016-01-01
This book is an exposition of the algebra and calculus of differential forms, of the Clifford and Spin-Clifford bundle formalisms, and of vistas to a formulation of important concepts of differential geometry indispensable for an in-depth understanding of space-time physics. The formalism discloses the hidden geometrical nature of spinor fields. Maxwell, Dirac and Einstein fields are shown to have representatives by objects of the same mathematical nature, namely sections of an appropriate Clifford bundle. This approach reveals unity in diversity and suggests relationships that are hidden in the standard formalisms and opens new paths for research. This thoroughly revised second edition also adds three new chapters: on the Clifford bundle approach to the Riemannian or semi-Riemannian differential geometry of branes; on Komar currents in the context of the General Relativity theory; and an analysis of the similarities and main differences between Dirac, Majorana and ELKO spinor fields. The exercises with solut...
Matano, T.; Machida, M.; Tsuchima, I.; Kawasumi, N.; Honda, K.; Hashimoto, K.; Martinic, N.; Zapata, J.; Navia, C. E.; Aquirre, C.
1985-01-01
Size distributions of air showers accompanied with bundle of high energy gamma rays and/or large size bursts under emulsion chambers, to study the composition of primary cosmic rays and also characteristics of high energy nuclear interaction. Air showers initiated by particles with a large cross section of interaction may develop from narrow region of the atmosphere near the top. Starting levels of air showers by particles with smaller cross section fluctuate in wider region of the atmosphere. Air showers of extremely small size accompanied with bundle of gamma rays may be ones initiated by protons at lower level after penetrating deep atmosphere without interaction. It is determined that the relative size distribution according to the total energy of bundle of gamma rays and the total burst size observed under 15 cm lead absorber.
Directory of Open Access Journals (Sweden)
Jasper van der Slegt
Full Text Available BACKGROUND: Surgical site infections (SSI's are associated with severe morbidity, mortality and increased health care costs in vascular surgery. OBJECTIVE: To implement a bundle of care in vascular surgery and measure the effects on the overall and deep-SSI's rates. DESIGN: Prospective, quasi-experimental, cohort study. METHODS: A prospective surveillance for SSI's after vascular surgery was performed in the Amphia hospital in Breda, from 2009 through 2011. A bundle developed by the Dutch hospital patient safety program (DHPSP was introduced in 2009. The elements of the bundle were (1 perioperative normothermia, (2 hair removal before surgery, (3 the use of perioperative antibiotic prophylaxis and (4 discipline in the operating room. Bundle compliance was measured every 3 months in a random sample of surgical procedures and this was used for feedback. RESULTS: Bundle compliance improved significantly from an average of 10% in 2009 to 60% in 2011. In total, 720 vascular procedures were performed during the study period and 75 (10.4% SSI were observed. Deep SSI occurred in 25 (3.5% patients. Patients with SSI's (28,5±29.3 vs 10.8±11.3, p<0.001 and deep-SSI's (48.3±39.4 vs 11.4±11.8, p<0.001 had a significantly longer length of hospital stay after surgery than patients without an infection. A significantly higher mortality was observed in patients who developed a deep SSI (Adjusted OR: 2.96, 95% confidence interval 1.32-6.63. Multivariate analysis showed a significant and independent decrease of the SSI-rate over time that paralleled the introduction of the bundle. The SSI-rate was 51% lower in 2011 compared to 2009. CONCLUSION: The implementation of the bundle was associated with improved compliance over time and a 51% reduction of the SSI-rate in vascular procedures. The bundle did not require expensive or potentially harmful interventions and is therefore an important tool to improve patient safety and reduce SSI's in patients undergoing
Preliminary assessment of noble gas bundle tagging using a partial krypton backfill
International Nuclear Information System (INIS)
Current limitations of CANDU reactors to reliably locate defective fuel bundles have sparked interest into new identification techniques. Noble gas tagging, which would involve the addition of specific combinations of Kr and Xe isotopes to the fuel-to-sheath gap during manufacturing, has the potential to offer a means of locating failed-fuel bundles. The released tag with a given isotopic signature could be measured in the primary heat transport system by mass spectrometry. This technique would allow on-power failure location. Moreover, the technique could be of particular interest for demonstration irradiations with new fuel bundle designs. This report outlines preliminary considerations towards a suitable tag isotope choice and discusses the impact on the thermal performance of a fuel element. The detection limit of two mass spectrometer systems was determined through measurements of prepared krypton samples with aqueous concentrations in the range of 10-12 to 10-9 [molKr/molH2O]. (author)
Mohan, Vandana; Sundaramoorthi, Ganesh; Kubicki, Marek; Terry, Douglas; Tannenbaum, Allen
2010-03-01
We propose a novel framework for population analysis of DW-MRI data using the Tubular Surface Model. We focus on the Cingulum Bundle (CB) - a major tract for the Limbic System and the main connection of the Cingulate Gyrus, which has been associated with several aspects of Schizophrenia symptomatology. The Tubular Surface Model represents a tubular surface as a center-line with an associated radius function. It provides a natural way to sample statistics along the length of the fiber bundle and reduces the registration of fiber bundle surfaces to that of 4D curves. We apply our framework to a population of 20 subjects (10 normal, 10 schizophrenic) and obtain excellent results with neural network based classification (90% sensitivity, 95% specificity) as well as unsupervised clustering (k-means). Further, we apply statistical analysis to the feature data and characterize the discrimination ability of local regions of the CB, as a step towards localizing CB regions most relevant to Schizophrenia.
Measurements of local temperature distributions in rod bundles with sodium flow
International Nuclear Information System (INIS)
In an electrically heated 19-rod bundle (P/D = 1.30, W/R = 1.40) with sodium flow the three-dimensional temperature fields in the rod clads were measured. The main characteristics of the test section are three adjacent heater rods in the duct wall zone instrumented on four measuring planes and rotatable by 3600 under full power conditions; furthermore spacer grids which are axially movable, and a system allowing to bow one heater rod over the last third of its heated length. The results of measurements of the azimuthal temperature variations of the rotatable rods are presented for different operating conditions (80 2), different spacer grid positions relative to the measuring planes and different bowing positions of one rod. For better understanding of the experimental results cross sections of the 19-rod bundle were prepared. It became evident, that a well-known bundle geometry is very important for the interpretation of the experimental results. (orig.)
Temperature field downstream of an heated bundle mock-up results for different power distribution
International Nuclear Information System (INIS)
The aim of these peculiar experiments performed on the ML4 loop in ISPRA is to evaluate the characteristics of the temperature field over a length of 20 to 30 dias downstream of a rod bundle for different temperatures profiles at the bundle outlet. The final purpose of this work will be to establish either directly or through models whether it is possible or not to detect subassembly failures using suitable of the subassembly outlet temperature signal. 15 hours of digital and analog recording were taped for five different power distributions in the bundle. The total power dissipation remained constant during the whole run. Two flow rates and seven axial location were investigated. It is shown that the different temperature profiles produce slight differences in the variance and skewness of the temperature signal measured along the axis of the pipe over 20 dias
Analysis of steady state combined forced and free convection data in rod bundles
International Nuclear Information System (INIS)
Fuel and blanket assemblies in an LMFBR are subjected to a wide range of power and power gradients during their life in the reactor. To accommodate these changes the assemblies operate in a wide range of flow regimes extending from forced convection, turbulent flow, to mixed convection, laminar flow. At low flow conditions the transverse temperature gradient in an assembly is considerably flattened because of energy redistribution by not only wire-wrap mixing and thermal conduction but also by flow redistribution because of buoyancy-induced crossflow. This has significance in LMFBR design. For the mixed convection regime of bundle operation, the transverse velocity profiles within a bundle change axially because of buoyancy-induced crossflow. It was therefore decided to use the ENERGY II and ENERGY III computer programs for the analysis of the rod bundle mixed convection data
Experimental study on high damped U-bend tube bundle of steam-generator
International Nuclear Information System (INIS)
This report shows an experimental study on the high damping characteristics of the U-bend tube bundle of Steam Generators in PWR-type nuclear power plants. The tube bundle is tied up with a rod-structure called anti-vibration bar (AVB)'. Four test models which are the partial but full-size mock-up of the practical plants are vibrationally excited on a three dimensional shaking table. It, at fist, shows the basic characteristics of the tube bundle. Secondary, the quantitative estimation of the damping ratio is reported. The vibrational characteristics greatly depend on the exciting direction. The minimum damping ratio in the out-of-plane direction is 8%, and the one in the in-plane direction is 15%. They are much higher than a present design damping ratio, 1%. (author)
Direct numerical simulation of transitional flow in a staggered tube bundle
Linton, D.; Thornber, B.
2016-02-01
A series of Direct Numerical Simulations (DNS) of the flow through a staggered tube bundle has been performed over the range 1030 ≤ Rem ≤ 5572 to capture the flow transition that occurs at the matrix transition point of Rem ≈ 3000. The matrix transition is the point at which a second frequency becomes prominent in tube bundles. To date, this is the highest published Reynolds number at which a DNS has been performed on cross-flow over a tube bundle. This study describes the flow behaviour in terms of: the mean flow field, Strouhal numbers, vortex shedding, 3-D flow features, and turbulence properties. These results support the hypothesis that the transition in the vortex shedding behaviour at Rem ≈ 3000 is similar to that which occurs in single cylinder flow at the equivalent Reynolds number. The visualisations presented also demonstrate the nature of the shedding mechanisms before and after the matrix transition point.
CFD analysis of turbulent cross-flow in a staggered tube bundle equipped with grooved cylinders
Directory of Open Access Journals (Sweden)
Imine O.
2013-04-01
Full Text Available This study describes the Computational Fluid Dynamics (CFD analysis of the turbulent cross-flow in a staggered tube bundle with transverse and longitudinal pitch-to-diameter ratio of 3.8 and 2.1 respectively. Two Longitudinal grooves are placed on the external surface at 90° and 270° degrees. Each cylinder has two grooves on the external surface of the cylinder. The Navier-Stokes equations of the turbulent flow are solved using Spalart almaras, k-ε realizable and k-ω SST, turbulence models provided by Fluent CFD code. The staggered tube bundle geometry simulations were performed at steady conditions. An adapted grid using static pressure, pressure coefficient and velocity gradient, furthermore, a second order upwind scheme were used. The CFD results were in agreement with the experimental data. The study demonstrates the capability of the CFD calculations in predicting flow characteristics around the bundle
The effects of the relative humidity (RH) of testing conditions on stelometer cotton flat bundle strength and elongation measurements, and on the morphology of fiber fractures are presented herein. A trend is observed for stelometer strength and elongations measurements; testing in conditions with h...
The Effects of Resource Bundling on Third-party Logistics Providers’ Performance
Directory of Open Access Journals (Sweden)
Noorliza Karia
2015-03-01
resource bundling (excluding advanced technology is required to achieve cost leadership. The effects of other resources on performance are mediated mainly by the demand management interface capability and knowledge resources. This is a novel attempt to justify the interaction and mediation effects of resources and capabilities on performance. The research highlights the needs for 3PL managers to focus on developing and bundling their demand management interface capability and knowledge resources in order to achieve cost leadership, and further combine advanced technology into such bundling of resources and capabilities to achieve innovation in customer service. It advances the application of resource-based view (RBV theory in logistics research by identifying resources that play supporting roles and examining the capabilities for enhancing 3PLs’ competitive performance.
CFD simulation of vertical seven-rod bundle cooled with supercritical Freon-12
Energy Technology Data Exchange (ETDEWEB)
Huang, X.; Podila, K.; Rao, Y.F., E-mail: podilak@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)
2014-06-15
In this paper, a seven-rod bare bundle was simulated using ANSYS Fluent 6.3.26 to accurately predict the fluid flow and heat transfer behaviour under supercritical flow conditions. Seven turbulence models were compared to identify the appropriate model to predict the experiments performed at the Institute of Physics and Power Engineering on a vertically oriented seven-rod bare bundle cooled with supercritical Freon-12. It was found that predictions of wall temperatures and heat transfer coefficients are sensitive to the choice of turbulence model as well as to the near-wall treatment. Overall, the CFD simulations were able to predict the measured sheath temperature profiles along the length of the bundle within reasonable accuracy. (author)
Electrostatically actuated oscillator of bundle and double-walled carbon nanotubes
International Nuclear Information System (INIS)
Schematics of capacitively driven carbon nanotube (CNT) oscillators were presented and investigated by using classical molecular dynamics simulations. While the capacitive force acting on a CNT oscillator extruded it, the force exerted by the excess van der Waals energy sucked the CNT oscillator into the bundle or outer shell. The CNT oscillator could be oscillated by using both the Coulomb and the van der Waals interactions. The van der Waals force of the bundle-type CNT oscillator was less than the van der Waals force of the double-walled CNT oscillator. Molecular dynamics simulation results showed that double-walled CNT oscillators were better than bundle-type CNT oscillators in the aspects of both energy dissipation and stable operation.
Electrostatically actuated oscillator of bundle and double-walled carbon nanotubes
Energy Technology Data Exchange (ETDEWEB)
Kang, Jeong Won; Song, Ki Oh; Hwang, Ho Jung [Chung-Ang University, Seoul (Korea, Republic of); Lee, Jun Ha; Lee, Hoong Joo [Sangmyung University, Chonan (Korea, Republic of); Kwon, Oh Keun [Semyung University, Jecheon (Korea, Republic of); Yoon, Young Sik; Song, Young Jin [Konyang University, Nonsan (Korea, Republic of)
2006-03-15
Schematics of capacitively driven carbon nanotube (CNT) oscillators were presented and investigated by using classical molecular dynamics simulations. While the capacitive force acting on a CNT oscillator extruded it, the force exerted by the excess van der Waals energy sucked the CNT oscillator into the bundle or outer shell. The CNT oscillator could be oscillated by using both the Coulomb and the van der Waals interactions. The van der Waals force of the bundle-type CNT oscillator was less than the van der Waals force of the double-walled CNT oscillator. Molecular dynamics simulation results showed that double-walled CNT oscillators were better than bundle-type CNT oscillators in the aspects of both energy dissipation and stable operation.
CALCULATION OF AERIAL CABLE SPACER COMPRESSION FORCES IN BUNDLED PHASES DURING SHORT CIRCUIT FAULT
Directory of Open Access Journals (Sweden)
I. I. Sergey
2014-01-01
Full Text Available The paper presents an approximate method for calculation of electrodynamic resistance parameters of a flexible bus-bar with bundled phases. Comparison of the approximate calculation results with the computer calculations using a FAZA software tool has been given in the paper. An evaluation of permissible aerial cable spacer compression forces for designed modern standard distribution substations of 330 and 550 kV has been provided in the paper. The paper proposes an algorithm for determination of dynamics parameters in a bundled phase with due account of influence pertaining to viscoelastic characteristics of damping spacers.
Li, Simon; Rehder, Kyle J; Giuliano, John S; Apkon, Michael; Kamat, Pradip; Nadkarni, Vinay M; Napolitano, Natalie; Thompson, Ann E; Tucker, Craig; Nishisaki, Akira
2016-01-01
Advanced airway management in the pediatric intensive care unit (PICU) is hazardous, with associated adverse outcomes. This report describes a methodology to develop a bundle to improve quality and safety of tracheal intubations. A prospective observational cohort study was performed with expert consensus opinion of 1715 children undergoing tracheal intubation at 15 PICUs. Baseline process and outcomes data in tracheal intubation were collected using the National Emergency Airway Registry for Children reporting system. Univariate analysis was performed to identify risk factors associated with adverse tracheal intubation-associated events. A multidisciplinary quality improvement committee was formed. Workflow analysis of tracheal intubation and pilot testing were performed to develop the Airway Bundle Checklist with 4 parts: (1) risk factor assessment, (2) plan generation, (3) preprocedure time-out to ensure that providers, equipment, and plans are prepared, (4) postprocedure huddle to identify improvement opportunities. The Airway Bundle Checklist developed may lead to improvement in airway management. PMID:25143411
Effective action of heterotic compactification on K3 with non-trivial gauge bundles
Energy Technology Data Exchange (ETDEWEB)
Schasny, Martin
2012-10-15
In this thesis we study the heterotic string compactified on K3 with non-trivial gauge bundles. We focus on two backgrounds, the well-known standard embedding and abelian line bundles. Using a Kaluza-Klein reduction, the six-dimensional effective action is computed up to terms of order {alpha}'{sup 2} with special attention on the hypermultiplet sector. We compute the moduli dependent couplings of the matter fields and analyze the geometry of the hyperscalar sigma model. Moreover, we prove the consistency with six-dimensional supergravity and derive the appropriate D-term scalar potential. For the line bundle backgrounds we show that the gauge flux stabilizes some geometrical moduli and renders some abelian vector multiplets massive.
Effective action of heterotic compactification on K3 with non-trivial gauge bundles
International Nuclear Information System (INIS)
In this thesis we study the heterotic string compactified on K3 with non-trivial gauge bundles. We focus on two backgrounds, the well-known standard embedding and abelian line bundles. Using a Kaluza-Klein reduction, the six-dimensional effective action is computed up to terms of order α'2 with special attention on the hypermultiplet sector. We compute the moduli dependent couplings of the matter fields and analyze the geometry of the hyperscalar sigma model. Moreover, we prove the consistency with six-dimensional supergravity and derive the appropriate D-term scalar potential. For the line bundle backgrounds we show that the gauge flux stabilizes some geometrical moduli and renders some abelian vector multiplets massive.
Schnauß, Jörg; Golde, Tom; Schuldt, Carsten; Schmidt, B. U. Sebastian; Glaser, Martin; Strehle, Dan; Händler, Tina; Heussinger, Claus; Käs, Josef A.
2016-03-01
Attractive depletion forces between rodlike particles in highly crowded environments have been shown through recent modeling and experimental approaches to induce different structural and dynamic signatures depending on relative orientation between rods. For example, it has been demonstrated that the axial attraction between two parallel rods yields a linear energy potential corresponding to a constant contractile force of 0.1 pN. Here, we extend pairwise, depletion-induced interactions to a multifilament level with actin bundles, and find contractile forces up to 3 pN. Forces generated due to bundle relaxation were not constant, but displayed a harmonic potential and decayed exponentially with a mean decay time of 3.4 s. Through an analytical model, we explain these different fundamental dynamics as an emergent, collective phenomenon stemming from the additive, pairwise interactions of filaments within a bundle.
Cooperative retraction of bundled type IV pili enables nanonewton force generation.
Directory of Open Access Journals (Sweden)
Nicolas Biais
2008-04-01
Full Text Available The causative agent of gonorrhea, Neisseria gonorrhoeae, bears retractable filamentous appendages called type IV pili (Tfp. Tfp are used by many pathogenic and nonpathogenic bacteria to carry out a number of vital functions, including DNA uptake, twitching motility (crawling over surfaces, and attachment to host cells. In N. gonorrhoeae, Tfp binding to epithelial cells and the mechanical forces associated with this binding stimulate signaling cascades and gene expression that enhance infection. Retraction of a single Tfp filament generates forces of 50-100 piconewtons, but nothing is known, thus far, on the retraction force ability of multiple Tfp filaments, even though each bacterium expresses multiple Tfp and multiple bacteria interact during infection. We designed a micropillar assay system to measure Tfp retraction forces. This system consists of an array of force sensors made of elastic pillars that allow quantification of retraction forces from adherent N. gonorrhoeae bacteria. Electron microscopy and fluorescence microscopy were used in combination with this novel assay to assess the structures of Tfp. We show that Tfp can form bundles, which contain up to 8-10 Tfp filaments, that act as coordinated retractable units with forces up to 10 times greater than single filament retraction forces. Furthermore, single filament retraction forces are transient, whereas bundled filaments produce retraction forces that can be sustained. Alterations of noncovalent protein-protein interactions between Tfp can inhibit both bundle formation and high-amplitude retraction forces. Retraction forces build over time through the recruitment and bundling of multiple Tfp that pull cooperatively to generate forces in the nanonewton range. We propose that Tfp retraction can be synchronized through bundling, that Tfp bundle retraction can generate forces in the nanonewton range in vivo, and that such high forces could affect infection.
The Preliminary Study for Numerical Computation of 37 Rod Bundle in CANDU Reactor
International Nuclear Information System (INIS)
A typical CANDU 6 fuel bundle consists of 37 fuel rods supported by two endplates and separated by spacer pads at various locations. In addition, the bearing pads are brazed to each outer fuel rod with the aim of reducing the contact area between the fuel bundle and the pressure tube. Although the recent progress of CFD methods has provided opportunities for computing the thermal-hydraulic phenomena inside of a fuel channel, it is yet impossible to reflect numerical computations on the detailed shape of rod bundle due to challenges with computing mesh and memory capacity. Hence, the previous studies conducted a numerical computation for smooth channels without considering spacers and bearing pads. But, it is well known that these components are an important factor to predict the pressure drop and heat transfer rate in a channel. In this study, the new computational method is proposed to solve complex geometry such as a fuel rod bundle. Before applying a solution to the problem of the 37 rod bundle, the validity and the accuracy of the method are tested by applying the method to simple geometry. The split channel method has been proposed with the aim of computing the fully shaped CANDU fuel channel with detailed components. The validity was tested by applying the method to the single channel problem. The average temperature have similar values for the considered two methods, while the local temperature shows a slight difference by the effect of conduction heat transfer in the solid region of a rod. Based on the present result, the calculation for the fully shaped 37-rod bundle is scheduled for future work
Indian Academy of Sciences (India)
Aydin Gezer
2009-06-01
The purpose of the present article is to investigate some relations between the Lie algebra of the infinitesimal fibre-preserving conformal transformations of the tangent bundle of a Riemannian manifold with respect to the synectic lift of the metric tensor and the Lie algebra of infinitesimal projective transformations of the Riemannian manifold itself.
Xie, Linfu; Hu, Han; Wang, Jingxue; Zhu, Qing; Chen, Min
2016-07-01
Combined bundle adjustment is a fundamental step in the processing of massive oblique images. Traditional bundle adjustment designed for nadir images gives identical weights to different parts of image point observations made from different directions, due to the assumption that the errors in the observations follow the same Gaussian distribution. However, because of their large tilt angles, aerial oblique images have trapezoidal footprints on the ground, and their areas correspond to conspicuously different ground sample distances. The errors in different observations no longer conform to the above assumption, which leads to suboptimal bundle adjustment accuracy and restricts subsequent 3D applications. To model the distribution of the errors correctly for the combined bundle adjustment of oblique images, this paper proposes an asymmetric re-weighting method. The scale of each pixel is used to determine a re-weighting factor, and each pixel is subsequently projected onto the ground to identify another anisotropic re-weighting factor using the shape of its quadrangle. Next, these two factors are integrated into the combined bundle adjustment using asymmetric weights for the image point observations; greater weights are assigned to observations with fine resolutions, and those with coarse resolutions are penalized. This paper analyzes urban and rural images captured by three different five-angle camera systems, from both proprietary datasets and the ISPRS/EuroSDR benchmark. The results reveal that the proposed method outperforms the traditional method in both back-projected and triangulated precision by approximately 5-10% in most cases. Furthermore, the misalignments of point clouds generated by the different cameras are significantly alleviated after combined bundle adjustment.
International Nuclear Information System (INIS)
The real-space dynamics and the nonlinear interactions among Fourier modes in elastic wave turbulence are investigated by simulating the Foppl-von Karman equation. We find that the bundle structures of ridges appear intermittently in the time evolution of the stretching energy field. The time-evolution of the nonlinearity indicates the existence of active and moderate phases in turbulent state. Conditional sampling analysis reveals that the bundle structure, which is the embodiment of the strong nonlinear interactions among modes, induces the energy supply from an external force to the system
Takaoka, Masanori; Yokoyama, Naoto
2015-01-01
The real-space dynamics and the nonlinear interactions among Fourier modes in elastic wave turbulence are investigated by simulating the Foppl-von Karman equation. We find that the bundle structures of ridges appear intermittently in the time evolution of the stretching energy field. The time-evolution of the nonlinearity indicates the existence of active and moderate phases in turbulent state. Conditional sampling analysis reveals that the bundle structure, which is the embodiment of the strong nonlinear interactions among modes, induces the energy supply from an external force to the system.
Cadherin-23 May Be Dynamic in Hair Bundles of the Model Sea Anemone Nematostella vectensis
Pei-Ciao Tang; Watson, Glen M.
2014-01-01
Cadherin 23 (CDH23), a component of tip links in hair cells of vertebrate animals, is essential to mechanotransduction by hair cells in the inner ear. A homolog of CDH23 occurs in hair bundles of sea anemones. Anemone hair bundles are located on the tentacles where they detect the swimming movements of nearby prey. The anemone CDH23 is predicted to be a large polypeptide featuring a short exoplasmic C-terminal domain that is unique to sea anemones. Experimentally masking this domain with anti...
Upper bounds for the essential dimension of the moduli stack of ${\\sl_{n}}$-bundles over a curve
Dhillon, Ajneet; Lemire, Nicole
2009-01-01
We find upper bounds for the essential dimension of various moduli stacks of $\\sln$-bundles over a curve. When $n$ is a prime power, our calculation computes the essential dimension of the stack of stable bundles exactly and the essential dimension is not equal to the dimension in this case.
International Nuclear Information System (INIS)
Fe3O4/PVP//Eu(BA)3phen/PVP magnetic-photoluminescent bifunctional bistrand-aligned composite nanofibers bundles based on ferroferric oxide(Fe3O4) nanoparticles and europium complex Eu(BA)3phen (BA = benzoic acid) were fabricated via electrospinning by employing a homemade parallel axial electrospinning setup with the side by side dual spinnerets for the first time. The structures, morphology, and properties of the as-prepared products were investigated in detail by X-ray diffraction, field-emission scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy (TEM), a fluorescence spectrometer, and a vibrating sample magnetometer. SEM analysis showed the average diameter of the individual-strand fiber of the bistrand-aligned composite nanofibers bundles was 200 ± 25 nm. TEM image demonstrated that Fe3O4 nanoparticles were only dispersed into one strand of the bistrand-aligned composite nanofibers bundles, and the average diameter of Fe3O4 nanoparticles was about 15 nm. Under the excitation of 274 nm ultraviolet light, Fe3O4/PVP//Eu(BA)3phen/PVP bistrand-aligned composite nanofibers bundles exhibited red emissions of predominant peaks at 592 and 616 nm, which were respectively attributed to the 5D0 → 7F1 and 5D0 → 7F2 transitions of Eu3+ ions. The fluorescence intensity of the bistrand-aligned composite nanofibers bundles was higher than that of Fe3O4/Eu(BA)3phen/PVP composite nanofibers, and was decreased with the increase of the amounts of Fe3O4 nanoparticles. The saturation magnetizations of the bistrand-aligned composite nanofibers bundles and the Fe3O4/Eu(BA)3phen/PVP composite nanofibers were about equal when the two nanostructures contained the same mass ratios of Fe3O4 nanoparticles, but the saturation magnetizations of the bistrand-aligned composite nanofibers bundles were increased with the increase of the amounts of Fe3O4 nanoparticles. The new type Fe3O4/PVP//Eu(BA)3phen/PVP bistrand-aligned composite nanofibers
Aretaeus of Cappadocia and his treatises on diseases.
Tekiner, Halil
2015-01-01
Aretaeus of Cappadocia is considered as one of the greatest medical scholars of Greco-Roman antiquity after Hippocrates. He presumably was a native or at least a citizen of Cappadocia, a Roman province in Asia Minor (Turkey), and most likely lived around the middle of the second century (A.D.) His eight volume treatise, written in Ionic Greek, entitled On the Causes, Symptoms and Cure of Acute and Chronic Diseases remained unknown until the middle of the 16th century when, in 1552, the first Latin edition was published. In this work, Aretaeus offered clinical descriptions of a number of diseases among which he gave classic accounts of asthma, epilepsy, pneumonia, tetanus, uterus cancer and different kinds of insanity. He differentiated nervous diseases and mental disorders and described hysteria, headaches, mania and melancholia. He also rendered the earliest clear accounts on coeliac disease, diphtheria and heart murmur, and gave diabetes its name. PMID:26037198
Self-assembly of CdS: from nanoparticles to nanorods and arrayed nanorod bundles
International Nuclear Information System (INIS)
The CdS nanoparticles have been assembled into CdS nanorods and arrayed nanorod bundles by a thioglycolic acid (TGA) assisted hydrothermal processes using sodium sulfide (Na2S) and thiourea ((NH2)2CS) as the sulfur source, respectively. High-resolution transmission electron microscopy (HRTEM) shows that the CdS nanorods are single crystalline and the arrayed nanorod bundles are polycrystalline in nature. It is believed that the CdS nanorods were formed through the cluster-to-cluster oriented attachment mechanism, while the CdS nanorods bundles were formed through the particle-to-particle oriented attachment mechanism. In addition, the optical properties of CdS nanostructures were characterized by photoluminescence spectra (PL) and Raman spectroscopy
Fast iteration of cocyles over rotations and Computation of hyperbolic bundles
Huguet, Gemma; Sire, Yannick
2011-01-01
In this paper, we develop numerical algorithms that use small requirements of storage and operations for the computation of hyperbolic cocycles over a rotation. We present fast algorithms for the iteration of the quasi-periodic cocycles and the computation of the invariant bundles, which is a preliminary step for the computation of invariant whiskered tori.
Asymptotics of certain families of Higgs bundles in the Hitchin component
DEFF Research Database (Denmark)
Collier, Brian; Li, Qiongling
2015-01-01
Using Hitchin's parameterization of the Hitchin-Teichm\\"uller component of the $SL(n,\\mathbb{R})$ representation variety, we study the asymptotics of certain families of representations. In fact, for certain Higgs bundles in the $SL(n,\\mathbb{R})$-Hitchin component, we study the asymptotics of th...
The Motive of the Moduli Stack of -Bundles over the Universal Curve
Indian Academy of Sciences (India)
Donu Arapura; Ajneet Dhillon
2008-08-01
We define relative motives in the sense of André. After associating a complex in the derived category of motives to an algebraic stack we study this complex in the case of the moduli of -bundles varying over the moduli of curves.
A finite element model for static strength analysis of CANDU fuel bundle
Energy Technology Data Exchange (ETDEWEB)
Horhoianu, G.; Ionescu, D.V. [Institute for Nuclear Research, Pitesti (Romania)
2006-08-15
A static strength analysis finite-element model has been developed using the ANSYS computer code in order to simulate the axial compression in CANDU type fuel bundle subject to hydraulic drag loads, deflection of fuel elements and stresses and displacements in the end plates. The validation of the finite-element model has been done by comparison with the out-reactor strength test results. Comparison of model predictions with the experimental results showed very good agreement. The comparative assessment reveals that SEU43 and SEU43L fuel bundles are able to withstand high flow rate without showing a significant geometric instability. (orig.)
Gilias, Guy
2015-03-01
In a long letter, Andreas Vesalius reacts to the comments made by Gabriel Falloppius to his work 'De Humani Corporis Fabrica'. In this letter, he proves Falloppius wrong in a number of assertions and corrects him on more than one occasion. In doing so, Vesalius as a renaissance humanist uses a classic Latin language with long elegant sentences in the style of the old Roman orator Cicero. Remarkably interesting is the fact that this whole argumentation is spiced with comparisons and examples from daily life. To make it clear to the reader what a certain part of the skeleton looks like, he compares this part with an object everybody knows. All parts of the human body are depicted in such an almost graphic way that even an interested reader without any medical or anatomic education can picture them. And Vesalius is very creative in doing so, an artist as it were with a very rich imagination. Moreover, it's remarkable how the famous anatomist manages to put himself on the level of any ordinary person, using comparative images on that level. This last work of Vesalius, which he himself considers to be a supplement to his De Humani Corporis Fabrica, deserves special attention, not only because it illustrates the scientific evolution of the anatomist Vesalius, but also because it offers an insight in the psychology of that fascinating scientist Andreas Vesalius. PMID:26137670
Student assessment of teaching effectiveness of "bundle of changes"-A paired, controlled trial
Directory of Open Access Journals (Sweden)
Seema Kalra
2011-01-01
Full Text Available Background : Inching toward optimum patient safety by training personnel is the prime aim of the ongoing medical education. Aims : To assess whether lectures targeted to improve quality care in ICU could improve ICU practitioners′ knowledge levels and to evaluate the effectiveness of teaching. Settings and Design : In this paired controlled trial, 50 ICU practitioners, i.e., anesthesia and medicine residents and nursing staff of our hospital attended a series of four lectures. Materials and Methods : Participants enrolled in the study attended lectures on "bundles of changes" in ICU, namely, introduction, ventilator bundle, central line bundle, and catheter-related blood stream infections and severe sepsis bundle. They were given a questionnaire of 15 multiple choice questions prior to and after the lectures. We evaluated their immediate knowledge acquisition and retention recall. Subsequently, they evaluated the effectiveness of the teaching programme by a questionnaire of 10 multiple choice questions. Statistical analysis used: Data for statistical analysis were tabulated and analyzed using SPSS-Pc 11.5 version software. Results : Fifty study participants completed all three questionnaires. There was an increase in the overall mean score in the post-lecture test (4.58 + 1.51 SD (P < 0.001. Overall mean score increased significantly from 8.30 + 1.34 SD in THE pre-lecture test - to 12.02 + 1.61 SD in the postlecture re-test (3.72 + 1.39 SD (P < 0.001. In the evaluation of teaching effectiveness 88% respondents agreed to most of the questions, signifying the effectiveness of the lectures. However, there were 10% who disagreed to the questions and only 2% strongly disagreed to all the questions. Conclusions : Teaching programmes such as the "bundle of changes" are effective in improving immediate knowledge acquisition and retention recall of the participants if designed keeping the target audience in mind.
Legland, David; Devaux, Marie-Françoise; Guillon, Fabienne
2014-01-01
The cellular structure of plant tissues is a key parameter for determining their properties. While the morphology of cells can easily be described, few studies focus on the spatial distribution of different types of tissues within an organ. As plants have various shapes and sizes, the integration of several individuals for statistical analysis of tissues distribution is a difficult problem. The aim of this study is to propose a method that quantifies the average spatial organisation of vascular bundles within maize stems, by integrating information from replicated images. In order to compare observations made on stems of different sizes and shapes, a spatial normalisation strategy was used. A model of average stem contour was computed from the digitisation of several stem slab images. Point patterns obtained from individual stem slices were projected onto the average stem to normalise them. Group-wise analysis of the spatial distribution of vascular bundles was applied on normalised data through the construction of average intensity maps. A quantitative description of average bundle organisation was obtained, via a 3D model of bundle distribution within a typical maize internode. The proposed method is generic and could easily be extended to other plant organs or organisms. PMID:24622152
Directory of Open Access Journals (Sweden)
David Legland
Full Text Available The cellular structure of plant tissues is a key parameter for determining their properties. While the morphology of cells can easily be described, few studies focus on the spatial distribution of different types of tissues within an organ. As plants have various shapes and sizes, the integration of several individuals for statistical analysis of tissues distribution is a difficult problem. The aim of this study is to propose a method that quantifies the average spatial organisation of vascular bundles within maize stems, by integrating information from replicated images. In order to compare observations made on stems of different sizes and shapes, a spatial normalisation strategy was used. A model of average stem contour was computed from the digitisation of several stem slab images. Point patterns obtained from individual stem slices were projected onto the average stem to normalise them. Group-wise analysis of the spatial distribution of vascular bundles was applied on normalised data through the construction of average intensity maps. A quantitative description of average bundle organisation was obtained, via a 3D model of bundle distribution within a typical maize internode. The proposed method is generic and could easily be extended to other plant organs or organisms.
Experimental investigation of turbulent transport of momentum and energy in a heated rod bundle
International Nuclear Information System (INIS)
The design of rod bundles is substantially improved by numerical simulation of the axial flow. The development of advanced turbulence models and the verification of existing computer codes need empirical information on turbulent transport properties of momentum and energy. A large number of experiments has been performed in various rod bundle geometries with isothermal flow. In contrast to this, the turbulent transport of energy has rarely been investigated in the past. The aim of the present work is to determine the turbulent properties of heated flow through a 37-rod bundle with triangular array. The fundamental differential equations describing turbulent flows are presented. The quantities to be determined experimentally are derived. All components of the instantaneous velocity and temperature are measured by hot wire anemometry. The computed turbulent quantities are presented for central and wall subchannels with two different pitch-to-diameter and wall-to-diameter ratios. It is shown that with decreasing gap width there is a significant deviation of the turbulence field from pipe flow. Detailed frequency analyses are performed for further characterisation of the large scale flow and temperature pulsations. These observations confirm the existence of an energetic coherent structure between adjacent subchannels. Spectral measurements with two hot wire probes imply a distinct similarity of motion of vortices in different subchannels of the bundle. (orig.)
Institute of Scientific and Technical Information of China (English)
张艳华; 冷宁; 宋蓉珍
2007-01-01
The article introduces Shakespeare's tragedy "Hamlet". Hamlet wants to revenge for his father. But when the opportunity is coming, he delays his revenge. The passage analyzes the causes of his delay from Hamlet's characters.
3-D slug flow heat transfer analysis of coupled coolant cells in finite LMFBR bundles
International Nuclear Information System (INIS)
A three-dimensional single region slug flow heat transfer analysis for finite LMFBR rod bundles using a classical analytical solution method has been performed. According to the isolated single cell analysis, the results show that the peripheral clad temperature variation as well as the thermal entrance length are strongly dependent upon the degree of irregularity displayed by various coolant geometries. Since under the present LMFBR conditions, fully-developed temperature fields may hardly be established in such characteristic rod bundle regions, a 3-D heat transfer analysis seems to be mandatory. This implies that the results of fully developed heat transfer analyses are by far too conservative
Importance of electrode positioning in the diagnosis of right bundle branch block.
Directory of Open Access Journals (Sweden)
Andrés Ramírez C.
2014-08-01
Full Text Available INTRODUCTION: The correct positioning of precordial electrodes of an electrocardiogram (ECG was agreed upon and formalized in 1938 by the American Heart Association (AHA and the Cardiac Society of Great Britain (CSGB , establishing the gold standard for the correct ECG procedure. The correct positioning of the electrodes is extremely important, with incorrect placement being related to right bundle branch block overdiagnosis and the subsequent social, psychological and economical effects of implying a pathological condition in a normal person. OBJECTIVE: To quantify the diagnosis of right bundle branch block in high right parasternal accessory leads (diagnostic test compared to classic precordial leads (gold standard. MATERIAL AND METHOD: A number of 100 consecutive patients were evaluated with resting 12-lead-electrocardiogram and high right parasternal accessory leads, after proper consent from patients. RESULTS: A 7% of patients presented right bundle branch block in classical precordial leads, compared with 29% in high right parasternal accessory leads. QRS complexes were all less than 120 milliseconds. DISCUSSION: There are not national available references analyzing electrode placement in the study of electrocardiographic abnormalities. There was an overdiagnosis of right bundle branch block in high right parasternal accessory leads. The association and relevance in the diagnosis of serious diseases, such as myocardial infarction and Brugada syndrome, makes the necessity of a solid foundation on electrocardiogram technique, of uttermost importance.
Directory of Open Access Journals (Sweden)
Deepak Joshi
2014-01-01
Full Text Available Background: Double bundle anterior cruciate ligament (DBACL reconstruction is said to reproduce the native anterior cruciate ligament (ACL anatomy better than single bundle anterior cruciate ligament, whether it leads to better functional results is debatable. Different fixation methods have been used for DBACL reconstruction, the most common being aperture fixation on tibial side and cortical suspensory fixation on the femoral side. We present the results of DBACL reconstruction technique, wherein on the femoral side anteromedial (AM bundle is fixed with a crosspin and aperture fixation was done for the posterolateral (PL bundle. Materials and Methods: Out of 157 isolated ACL injury patients who underwent ACL reconstruction, 100 were included in the prospective study. Arthroscopic DBACL reconstruction was done using ipsilateral hamstring autograft. AM bundle was fixed using Transfix (Arthrex, Naples, FL, USA on the femoral side and bio interference screw (Arthrex, Naples, FL, USA on the tibial side. PL bundle was fixed on femoral as well as on tibial side with a biointerference screw. Patients were evaluated using KT-1000 arthrometer, Lysholm score, International Knee Documentation Committee (IKDC Score and isokinetic muscle strength testing. Results: The KT-1000 results were evaluated using paired t test with the P value set at 0.001. At the end of 1 year, the anteroposterior side to side translation difference (KT-1000 manual maximum showed mean improvement from 5.1 mm ± 1.5 preoperatively to 1.6 mm ± 1.2 ( P < 0.001 postoperatively. The Lysholm score too showed statistically significant ( P < 0.001 improvement from 52.4 ± 15.2 (range: 32-76 preoperatively to a postoperative score of 89.1 Â± 3.2 (range 67-100. According to the IKDC score 90% patients had normal results (Category A and B. The AM femoral tunnel initial posterior blow out was seen in 4 patients and confluence in the intraarticular part of the femoral tunnels was seen in 6
Moduli of endomorphisms of semistable vector bundles over a compact Riemann surface
International Nuclear Information System (INIS)
We consider the moduli problem for endomorphisms of indecomposable semistable vector bundles over a compact convected Riemann surface of genus g greater than two. We develop the 3-dimensional case, which gives an idea of how to solve the moduli problem in general. 13 refs
MRI diagnosis of ACL bundle tears: value of oblique axial imaging
Energy Technology Data Exchange (ETDEWEB)
Ng, Alex W.H.; Griffith, James F.; Hung, Esther H.Y. [Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince of Wales Hospital, Shatin, NT, Hong Kong SAR (China); Law, Kan Yip; Yung, Patrick S.H. [Chinese University of Hong Kong, Department of Orthopedics and Traumatology, Prince of Wales Hospital, Shatin, NT, Hong Kong SAR (China)
2013-02-15
To investigate the diagnostic accuracy of oblique axial intermediate weighting MR imaging in detecting partial thickness anterior cruciate ligament (ACL) bundle tears. The study protocol was approved by the institutional ethics committee. Sixty-one subjects (43 male, 18 female; mean age 27.4 years; range 9 to 57 years) with clinically suspected ACL tear or meniscal tear between September 2009 and January 2011 were studied with MRI and arthroscopy. Detection of partial tear for the ACL as a whole and for each ACL bundle by protocol A (standard orthogonal sequences) and protocol B (standard orthogonal sequences plus oblique axial intermediate weighted imaging) was compared in a blinded fashion. Performance characteristics for protocol A and protocol B were compared using sensitivity, specificity, accuracy and ROC curves. A two-tailed p value of <0.05 indicated statistical significance. Fifteen (24.6%) normal, 15 (24.6%) partial and 31 complete tears were diagnosed by arthroscopy. Sensitivity, specificity and accuracy of protocol A for the diagnosis of partial tear of the ACL was 33%, 87% and 74%, while for protocol B the values were 87%, 87% and 87% respectively. The area under the curve (AUC) for the diagnosis of partial ACL tear and individual bundle tear was higher for protocol B, although this difference did not reach statistical significance (p > 0.05). The addition of oblique axial imaging to standard MR imaging improves diagnostic accuracy for detecting partial tears of the ACL as well as individual bundle tears of the ACL. (orig.)
Evaluation of nonequilibrium effects in bundle dispersed-flow film boiling
International Nuclear Information System (INIS)
The effects of thermodynamic nonequilibrium in dispersed flow film boiling heat transfer are examined. Steady-state and transient rod-bundle data are used to evaluate several empirical heat-transfer models commonly employed to predict post-CHF behavior. The models that account for thermodynamic nonequilibrium perform adequately, while those that ignore nonequilibrium effects incur errors in wall superheat as high as 1900K. Nonequilibrium effects can also be treated by explicitly modeling the phenomena. The thermal-hydraulic code COBRA-TF employs this approach. Using bundle data, the models in the code are evaluated. Analysis suggests that the interfacial heat transfer is overpredicted
International Nuclear Information System (INIS)
The advantages of an in-reactor monitoring system as compared with external control and measuring devices are discussed. A short historic retrospective of the in-reactor monitorino. system development is given with the stress on unresolved problems. Realization of such a system on the basis of a diagnostic fuel rod bundle with controlled coolant flow rats is considered. The scientific objectives of the diagnostic rod bundle development proo.ramme are identified. For DK1 and DK2 diagnostic rod bundles specification lists of measured parameters and corresponding sensors are presented. Problems of advanced design diagnostic fuel rod bundles (DK3 family) development are discussed. DK1 - 2 bundle is described in detail as well as the data acquisition and processing system and the results of experiments on Rheinsberg NPP
On Rationality of Moduli Spaces of Vector Bundles on Real Hirzebruch Surfaces
Indian Academy of Sciences (India)
Indranil Biswas; Ronnie Sebastian
2013-05-01
Let be a real form of a Hirzebruch surface. Let $M_H(r,c_1,c_2)$ be the moduli space of vector bundles on . Under some numerical conditions on $r,c_1$ and $c_2$, we identify those $M_H(r,c_1,c_2)$ that are rational.
Land lease contracts: properties and the value of bundles of property rights
Slangen, L.H.G.; Polman, N.B.P.
2008-01-01
Contracts are mechanisms for carrying out transactions. Leasing land is a voluntary transaction in which property rights - such as user and income rights - are transferred from landowners to tenants. The bundle of property rights transferred within a lease transaction varies with the type of contrac
Lamaming, Junidah; Hashim, Rokiah; Leh, Cheu Peng; Sulaiman, Othman; Sugimoto, Tomoko; Nasir, Mohammed
2015-12-10
In this study cellulose nanocrystals were isolated through acid hydrolysis process from parenchyma and vascular bundle of oil palm trunk (Elaeis guineensis). The morphological properties of obtained cellulose nanocrystals were studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The microscopy images showed smoother and cleaner surface of parenchyma cellulose nanocrystals when compared to vascular bundle cellulose nanocrystals. The TEM image shows a higher length and diameter for parenchyma cellulose nanocrystals compared to vascular bundle cellulose nanocrystals. The Fourier transform infrared (FTIR) spectra showed changes in functional groups after acid hydrolysis due to removal of lignin, hemicelluloses and other impurities in both type of cellulose nanocrystals. Crystallinity index of cellulose nanocrystals was observed higher for vascular bundle as compared to parenchyma. Thermogravimetric analysis (TGA) was performed to study the thermal stability of cellulose nanocrystals and it was observed higher for parenchyma cellulose nanocrystals compared to vascular bundle. PMID:26428155
Isomorphism of Compactiﬁcations of Vector Bundles Moduli: Nonreduced Moduli
Directory of Open Access Journals (Sweden)
N. V. Timofeeva
2015-12-01
Full Text Available We continue the study of the compactiﬁcation of the moduli scheme for Gieseker-semistable vector bundles on a nonsingular irreducible projective algebraic surface S with polarization L, by locally free sheaves. The relation of main components of the moduli functor or admissible semistable pairs and main components of the Gieseker – Maruyama moduli functor (for semistable torsion-free coherent sheaves with the same Hilbert polynomial on the surface S is investigated. The compactiﬁcation of interest arises when families of Gieseker-semistable vector bundles E on the nonsingular polarized projective surface (S, L are completed by vector bundles E on projective polarized schemes (S, L of special form. The form of the scheme S, of its polarization L and of the vector bundle E is described in the text. The collection ((S, L, E is called a semistable admissible pair. Vector bundles E on the surface (S, L and E on schemes (S, L are supposed to have equal ranks and Hilbert polynomials which are compute with respect to polarizations L and L, respectively. Pairs of the form ((S, L, E named as S-pairs are also included into the class under the scope. Since the purpose is to study the compactiﬁcation of moduli space for vector bundles, only families which contain S-pairs are considered. We build up the natural transformation of the moduli functor for admissible semistable pairs to the Gieseker – Maruyama moduli functor for semistable torsion-free coherent sheaves on the surface (S, L, with same rank and Hilbert polynomial. It is demonstrated that this natural transformation is inverse to the natural transformation built in the preceding paper and deﬁned by the standard resolution of a family of torsion-free coherent sheaves with a possibly nonreduced base scheme. The functorial isomorphism constructed determines the scheme isomorphism of compactiﬁcations of moduli space for semistable vector bundles on the surface (S, L.
International Nuclear Information System (INIS)
It is well known that a fluid may strongly influence the dynamic behaviour of a structure. Many different physical phenomena may take place, depending on the conditions: fluid flow, fluid at rest, little or high displacements of the structure. Inertial effects can take place, with lower vibration frequencies, dissipative effects also, with damping, instabilities due to the fluid flow (Fluid Induced Vibration). In this last case the structure is excited by the fluid. Tube bundles structures are very common in the nuclear industry. The reactor cores and the steam generators are both structures immersed in a fluid which may be submitted to a seismic excitation or an impact. In this case the structure moves under an external excitation, and the movement is influence by the fluid. The main point in such system is that the geometry is complex, and could lead to very huge sizes for a numerical analysis. Homogenization models have been developed based on the Euler equations for the fluid. Only inertial effects are taken into account. A next step in the modelling is to build models based on the homogenization of the Navier-Stokes equations. The papers presents results on an important step in the development of such model: the analysis of the fluid flow in a oscillating tube bundle. The analysis are made from the results of simulations based on the Navier-Stokes equations for the fluid. Comparisons are made with the case of the oscillations of a single tube, for which a lot of results are available in the literature. Different fluid flow pattern may be found, depending in the Reynolds number (related to the velocity of the bundle) and the Keulegan Carpenter number (related to the displacement of the bundle). A special attention is paid to the quantification of the inertial and dissipative effects, and to the forces exchanges between the bundle and the fluid. The results of such analysis will be used in the building of models based on the homogenization of the Navier
Assessment of ASSERT-PV for prediction of post-dryout heat transfer in CANDU bundles
International Nuclear Information System (INIS)
Highlights: • Assessment of the new Canadian subchannel code ASSERT-PV 3.2 for PDO sheath temperature prediction. • CANDU 28-, 37- and 43-element bundle PDO experiments. • Prediction improvement of ASSERT-PV 3.2 over previous code versions. • Sensitivity study of the effect of PDO model options. - Abstract: Atomic Energy of Canada Limited (AECL) has developed the subchannel thermalhydraulics code ASSERT-PV for the Canadian nuclear industry. The recently released ASSERT-PV 3.2 provides enhanced models for improved predictions of subchannel flow distribution, critical heat flux (CHF), and post-dryout (PDO) heat transfer in horizontal CANDU fuel channels. This paper presents results of an assessment of the new code version against PDO tests performed during five full-size CANDU bundle experiments conducted between 1992 and 2009 by Stern Laboratories (SL), using 28-, 37- and 43-element bundles. A total of 10 PDO test series with varying pressure-tube creep and/or bearing-pad height were analyzed. The SL experiments encompassed the bundle geometries and range of flow conditions for the intended ASSERT-PV applications for existing CANDU reactors. Code predictions of maximum PDO fuel-sheath temperature were compared against measurements from the SL PDO tests to quantify the code's prediction accuracy. The prediction statistics using the recommended model set of ASSERT-PV 3.2 were compared to those from previous code versions. Furthermore, separate-effects sensitivity studies quantified the contribution of each PDO model change or enhancement to the improvement in PDO heat transfer prediction. Overall, the assessment demonstrated significant improvement in prediction of PDO sheath temperature in horizontal fuel channels containing CANDU bundles
Assessment of ASSERT-PV for prediction of critical heat flux in CANDU bundles
International Nuclear Information System (INIS)
Highlights: • Assessment of the new Canadian subchannel code ASSERT-PV 3.2 for CHF prediction. • CANDU 28-, 37- and 43-element bundle CHF experiments. • Prediction improvement of ASSERT-PV 3.2 over previous code versions. • Sensitivity study of the effect of CHF model options. - Abstract: Atomic Energy of Canada Limited (AECL) has developed the subchannel thermalhydraulics code ASSERT-PV for the Canadian nuclear industry. The recently released ASSERT-PV 3.2 provides enhanced models for improved predictions of flow distribution, critical heat flux (CHF), and post-dryout (PDO) heat transfer in horizontal CANDU fuel channels. This paper presents results of an assessment of the new code version against five full-scale CANDU bundle experiments conducted in 1990s and in 2009 by Stern Laboratories (SL), using 28-, 37- and 43-element (CANFLEX) bundles. A total of 15 CHF test series with varying pressure-tube creep and/or bearing-pad height were analyzed. The SL experiments encompassed the bundle geometries and range of flow conditions for the intended ASSERT-PV applications for CANDU reactors. Code predictions of channel dryout power and axial and radial CHF locations were compared against measurements from the SL CHF tests to quantify the code prediction accuracy. The prediction statistics using the recommended model set of ASSERT-PV 3.2 were compared to those from previous code versions. Furthermore, the sensitivity studies evaluated the contribution of each CHF model change or enhancement to the improvement in CHF prediction. Overall, the assessment demonstrated significant improvement in prediction of channel dryout power and axial and radial CHF locations in horizontal fuel channels containing CANDU bundles
Assessment of ASSERT-PV for prediction of post-dryout heat transfer in CANDU bundles
Energy Technology Data Exchange (ETDEWEB)
Cheng, Z., E-mail: chengz@aecl.ca; Rao, Y.F., E-mail: raoy@aecl.ca; Waddington, G.M., E-mail: waddingg@aecl.ca
2014-10-15
Highlights: • Assessment of the new Canadian subchannel code ASSERT-PV 3.2 for PDO sheath temperature prediction. • CANDU 28-, 37- and 43-element bundle PDO experiments. • Prediction improvement of ASSERT-PV 3.2 over previous code versions. • Sensitivity study of the effect of PDO model options. - Abstract: Atomic Energy of Canada Limited (AECL) has developed the subchannel thermalhydraulics code ASSERT-PV for the Canadian nuclear industry. The recently released ASSERT-PV 3.2 provides enhanced models for improved predictions of subchannel flow distribution, critical heat flux (CHF), and post-dryout (PDO) heat transfer in horizontal CANDU fuel channels. This paper presents results of an assessment of the new code version against PDO tests performed during five full-size CANDU bundle experiments conducted between 1992 and 2009 by Stern Laboratories (SL), using 28-, 37- and 43-element bundles. A total of 10 PDO test series with varying pressure-tube creep and/or bearing-pad height were analyzed. The SL experiments encompassed the bundle geometries and range of flow conditions for the intended ASSERT-PV applications for existing CANDU reactors. Code predictions of maximum PDO fuel-sheath temperature were compared against measurements from the SL PDO tests to quantify the code's prediction accuracy. The prediction statistics using the recommended model set of ASSERT-PV 3.2 were compared to those from previous code versions. Furthermore, separate-effects sensitivity studies quantified the contribution of each PDO model change or enhancement to the improvement in PDO heat transfer prediction. Overall, the assessment demonstrated significant improvement in prediction of PDO sheath temperature in horizontal fuel channels containing CANDU bundles.
On the synectic metric in the tangent bundle of a Riemannian manifold
Aras, Melek
2013-01-01
The purpose of this paper is to investigate applications the covariant derivatives of the covector fields and killing vector fields with respect to the synectic lift a in a the Riemannian manifold to its tangent bundle, where Cg-complete lift of the Riemannian metric, Va-vertical lift of the symmetric tens field of type (0,2) in Mn .
Scratch preventing method of assembling nuclear fuel bundles, and the assembly
International Nuclear Information System (INIS)
This patent describes a method of assembling a bundle of nuclear fuel elements for service in a nuclear reactor. It comprises a group of fuel rod elements each arranged in a space apart, parallel array and thus secured by each element traversing through a series of spacing units positioned at intervals along the length of the grouped fuel rod elements and having openings for receiving the fuel rod elements traversing therethrough, consisting essentially of the steps of: providing a scratch resisting, temporary protective barrier consisting of a water soluble coating of sodium silicate covering the outer surface of the fuel rod elements, then assembling the fuel bundle by passing each of the fuel rod elements through the openings of a series of spacing units positioned at intervals to fit together an adjoined composite fuel bundle assembly of a spaced apart parallel array of the fuel rod elements secured with spacing units, and removing the scratch resisting, temporary protective barrier consisting of water soluble coating of sodium silicate from the assembled fuel bundle with hot water
On $K$-theory automorphisms related to bundles of finite order
Ershov, A. V.
2009-01-01
In the present paper we describe the action of (not necessarily line) bundles of finite order on the $K$-functor in terms of classifying spaces. This description might provide with an approach for more general twistings in $K$-theory than ones related to the action of the Picard group.
A higher categorical analogue of topological T-duality for sphere bundles
Lind, John A; Westerland, Craig
2016-01-01
We introduce a periodic form of the iterated algebraic K-theory of ku, the (connective) complex K-theory spectrum, as well as a natural twisting of this cohomology theory by higher gerbes. Furthermore, we prove a form of topological T-duality for sphere bundles oriented with respect to this theory.
Scalable synthesis of aligned carbon nanotubes bundles using green natural precursor: neem oil
Kumar, Rajesh; Tiwari, Radhey Shyam; Srivastava, Onkar Nath
2011-12-01
Practical application of aligned carbon nanotubes (ACNTs) would have to be determined by a matter of its economical and large-scale preparation. In this study, neem oil (also named Margoaa oil, extracted from the seeds of the neem-- Azadirachta indica) was used as carbon source to fabricate the bundles of ACNTs. ACNTs have been synthesized by spray pyrolysis of neem oil and ferrocene mixture at 825°C. The major components of neem oil are hydrocarbon with less amount of oxygen, which provided the precursor species in spray pyrolysis growth of CNTs. The bundles of ACNTs have been grown directly inside the quartz tube. The as-grown ACNTs have been characterized through Raman spectroscopy, scanning and transmission electron microscopic (SEM/TEM) techniques. SEM images reveal that the bundles of ACNTs are densely packed and are of several microns in length. High-resolution TEM analysis reveals these nanotubes to be multi-walled CNTs. These multi-walled CNTs were found to have inner diameter between 15 and 30 nm. It was found that present technique gives high yield with high density of bundles of ACNTs.
Scalable synthesis of aligned carbon nanotubes bundles using green natural precursor: neem oil
Directory of Open Access Journals (Sweden)
Kumar Rajesh
2011-01-01
Full Text Available Abstract Practical application of aligned carbon nanotubes (ACNTs would have to be determined by a matter of its economical and large-scale preparation. In this study, neem oil (also named Margoaa oil, extracted from the seeds of the neem--Azadirachta indica was used as carbon source to fabricate the bundles of ACNTs. ACNTs have been synthesized by spray pyrolysis of neem oil and ferrocene mixture at 825°C. The major components of neem oil are hydrocarbon with less amount of oxygen, which provided the precursor species in spray pyrolysis growth of CNTs. The bundles of ACNTs have been grown directly inside the quartz tube. The as-grown ACNTs have been characterized through Raman spectroscopy, scanning and transmission electron microscopic (SEM/TEM techniques. SEM images reveal that the bundles of ACNTs are densely packed and are of several microns in length. High-resolution TEM analysis reveals these nanotubes to be multi-walled CNTs. These multi-walled CNTs were found to have inner diameter between 15 and 30 nm. It was found that present technique gives high yield with high density of bundles of ACNTs.
Line bundles over families of (super) Riemann surfaces. II: The graded case
Bruzzo, U.; Domínguez Pérez, J. A.
1993-04-01
A relative Picard theory in the context of graded manifolds is introduced. A Berezinian calculus and a theory of connections over SUSY-curves are systematically developed, and used to prove a Gauss-Bonnet theorem for line bundles in that setting and to discuss the validity of a flatness theorem.
Weak point property and sections of Picard bundles on a compactified Jacobian over a nodal curve
Indian Academy of Sciences (India)
USHA N BHOSLE; SANJAY SINGH
2016-08-01
We show that the compactified Jacobian (and its desingularization) of an integral nodal curve $Y$ satisfies the weak point property and the Jacobian of $Y$ satisfies the diagonal property. We compute some cohomologies of Picard bundles on the compactified Jacobian and its desingularization
Line Bundles Over Families of (SUPER) Riemann Surfaces. II: The Graded Case
Bruzzo, U.; Perez, J. A. Dominguez
1992-01-01
A relative Picard theory in the context of graded manifolds is introduced. A Berezinian calculus and a theory of connections over SUSY-curves are systematically developed, and used to prove a Gauss-Bonnet theorem for line bundles in that setting and to discuss the validity of a flatness theorem
Line Bundles Over Families of (SUPER) Riemann Surfaces; 2, The Graded Case
Bruzzo, U
1992-01-01
A relative Picard theory in the context of graded manifolds is introduced. A Berezinian calculus and a theory of connections over SUSY-curves are systematically developed, and used to prove a Gauss-Bonnet theorem for line bundles in that setting and to discuss the validity of a flatness theorem
Construction of an A-manifold on a principal torus bundle
Directory of Open Access Journals (Sweden)
Grzegorz Zborowski
2013-02-01
Full Text Available We construct a new example of an A-manifold, i.e. a Riemannian manifold with cyclic-parallel Ricci tensor. This condition can be viewed as a generalization of the Einstein condition. The underlying manifold for our construction is a principal torus bundle over Kähler-Einstein manifold with fibre a torus of arbitrary dimension.
Construction of an A-manifold on a principal torus bundle
Grzegorz Zborowski
2012-01-01
We construct a new example of an A-manifold, i.e. a Riemannian manifold with cyclic-parallel Ricci tensor. This condition can be viewed as a generalization of the Einstein condition. The underlying manifold for our construction is a principal torus bundle over Kähler-Einstein manifold with fibre a torus of arbitrary dimension.
Hydrodynamic Experiments for a Flow Distribution of a 61-pin Wire-wrapped Rod Bundle
International Nuclear Information System (INIS)
Fuel assembly of the SFR (Sodium-cooled Fast breeder Reactor) type reactor generally has wire spacers which are wrapped around each fuel pin helically in axial direction. The configuration of a helical wire spacer guarantees the fuel rods integrity by providing the bundle rigidity, proper spacing between rods and promoting coolant mixing between subchannels. It is important to understand the flow characteristics in such a triangular array wire wrapped rod bundle in a hexagonal duct. The experimental work has been undertaken to quantify the friction and mixing parameters which characterize the flow distribution in subchannels for the KAERI's own bundle geometric configuration. This work presents the hydrodynamic experimental results for the flow distribution and the pressure drop in subchannels of a 61-pin wire wrapped rod bundle which has been fabricated considering the hydraulic similarity of the reference reactor. Hydrodynamic experiments for a 61-pin wire wrapped test assembly has been performed to provide the data of a flow distribution and pressure losses in subchannels for verifying the analysis capability of subchannel analysis codes for a KAERI's own prototype SFR reactor. Three type of sampling probes have been specially designed to conserve the shape of the flow area for each type of subchannels. All 126 subchannels have been measured to identify the characteristics of the flow distribution in a 37-pin rod assembly. Pressure drops at the interior and the edge subchannels have been also measured to recognize the friction losses of each type of subchannels
Bochner-Hartogs type extension theorem for roots and logarithms of holomorphic line bundles
Ivashkovich, Sergey
2011-01-01
We prove an extension theorem for roots and logarithms of holomorphic line bundles across strictly pseudoconcave boundaries: they extend in all cases except one, when dimension and Morse index of a critical point is two. In that case we give an explicit description of obstructions to the extension.
International Nuclear Information System (INIS)
Let Mg denote the moduli space of compact Riemann surfaces of genus g. Mumford had proved, for each fixed genus g, that there are isomorphisms asserting that certain higher DET bundles over Mg are certain fixed (genus-independent) tensor power of the Hodge line bundle on Mg. We obtain a coherent, genus-independent description of the Mumford isomorphisms over certain infinite-dimensional ''universal'' parameter spaces of compact Riemann surfaces (with or without marked points). We work with an inductive limit of Teichmueller spaces comprising complex structures on a certain ''solenoidal Riemann surface'', H∞,ab, which appears as the inverse limit of an inverse system of surfaces of different general connected by abelian covering maps. We construct the universal Hodge and higher DET line bundles on this direct limit of Teichmueller spaces (in the sense of Shafarevich). The main result shows how such DET line bundles on the direct limit carry coherently-glued Quillen metrics and are related by the appropriate Mumford isomorphisms. Our work can be viewed as a contribution to a non-perturbative formulation of the Polyakov measure structure in a genus-independent fashion. (author). 22 refs
The Development of Lexical Bundle Accuracy and Production in English Second Language Speakers
Crossley, Scott; Salsbury, Thomas Lee
2011-01-01
Six adult, second language (L2) English learners were observed over a period of one year to explore the development of lexical bundles (i.e., bigrams) in naturally produced, oral English. Total bigrams produced by the L2 learners over the year of observation that were shared with native speakers were compared using a frequency index to explore L2…
Input modelling of ASSERT-PV V2R8M1 for RUFIC fuel bundle
International Nuclear Information System (INIS)
This report describes the input modelling for subchannel analysis of CANFLEX-RU (RUFIC) fuel bundle which has been developed for an advanced fuel bundle of CANDU-6 reactor, using ASSERT-PV V2R8M1 code. Execution file of ASSERT-PV V2R8M1 code was recently transferred from AECL under JRDC agreement between KAERI and AECL. SSERT-PV V2R8M1 which is quite different from COBRA-IV-i code has been developed for thermalhydraulic analysis of CANDU-6 fuel channel by subchannel analysis method and updated so that 43-element CANDU fuel geometry can be applied. Hence, ASSERT code can be applied to the subchannel analysis of RUFIC fuel bundle. The present report was prepared for ASSERT input modelling of RUFIC fuel bundle. Since the ASSERT results highly depend on user's input modelling, the calculation results may be quite different among the user's input models. The objective of the present report is the preparation of detail description of the background information for input data and gives credibility of the calculation results
International Nuclear Information System (INIS)
This paper describes an electrochemical model, which studies the performance of multi-bundles integrated-planar solid oxide fuel cell (IP-SOFC strip) fuelled by pure hydrogen. Following a description of the basic geometries and general premises the approaches and simplifications for the calculation of ohmic resistance, gas flow, heat and mass transfers are given. The effect of fuel pressure ratio and the temperature variation are investigated in a parameter study. The model results have been validates well with experimental data obtained from a full-size prototype of IP-SOFC technology for the second generation hybrid application; it is found that the ohmic and cathode activation overpotentials represent a major loss in fuel cell voltage. The results obtained from both strips also demonstrated acceptable performance and good reproducibility bundles to bundles at 900 deg. C. These results indicated weak effect of parameter variation on the bundles to bundles performances.
Energy Technology Data Exchange (ETDEWEB)
Mounir, H. [L2MCS - Laboratoire de Mecanique des Materiaux et Calcul des Structures de l' ENSET de Rabat, ENSET-Rabat, B.P. 6207, Av. Armee Royale, Badinat Al Irfane Rabat (Morocco); Laboratoire de Thermodynamique et Mecaniques des Materiaux, Faculte des Sciences de Rabat (Morocco); El Gharad, A. [L2MCS - Laboratoire de Mecanique des Materiaux et Calcul des Structures de l' ENSET de Rabat, ENSET-Rabat, B.P. 6207, Av. Armee Royale, Badinat Al Irfane Rabat (Morocco); Belaiche, M. [Laboratoire Magnetisme, Materiaux Magnetiques, Micro-onde et ceramique, Ecole normale superieure, BP 9235, Ocean Rabat 1000 (Morocco); Boukalouch, M. [Laboratoire de Thermodynamique et Mecaniques des Materiaux, Faculte des Sciences de Rabat (Morocco)
2009-10-15
This paper describes an electrochemical model, which studies the performance of multi-bundles integrated-planar solid oxide fuel cell (IP-SOFC strip) fuelled by pure hydrogen. Following a description of the basic geometries and general premises the approaches and simplifications for the calculation of ohmic resistance, gas flow, heat and mass transfers are given. The effect of fuel pressure ratio and the temperature variation are investigated in a parameter study. The model results have been validates well with experimental data obtained from a full-size prototype of IP-SOFC technology for the second generation hybrid application; it is found that the ohmic and cathode activation overpotentials represent a major loss in fuel cell voltage. The results obtained from both strips also demonstrated acceptable performance and good reproducibility bundles to bundles at 900 C. These results indicated weak effect of parameter variation on the bundles to bundles performances. (author)
Metallic/semiconducting ratio of carbon nanotubes in a bundle prepared using CVD technique
Indian Academy of Sciences (India)
Khurshed Ahmad Shah; S S Islam; H S Mavi; A K Shukla; Harsh
2006-08-01
We present an investigation of the nature of single-walled carbon nanotubes (SWCNTs) in a bundle by resonant Raman spectroscopy. The calculation has been done for the three peak positions in radial breathing mode (RBM) spectra obtained by using a laser excitation wavelength () of 633 nm from He–Ne laser on SWNT bundle sample prepared by chemical vapor deposition (CVD) technique using iron catalyst at 800° C. The detailed analysis in the present study is focused on peak positions 162 cm-1, 186 cm-1, and 216 cm-1. The first step of the analysis is to construct a list of possible (, ) pairs from the diameters calculated from the RBM peak positions. The parameters of SWNTs studied gives in-depth understanding of many symmetry, resonance and characteristic properties of SWNT bundles. Our results indicate that the contribution of metallic SWNTs in the bundle is small at RBM peak positions 162 cm-1, 186 cm-1 and in agreement with pervious results at peak position 216 cm-1.
Directory of Open Access Journals (Sweden)
Timo Maier
Full Text Available Filamentous actin is one of the most important cytoskeletal elements. Not only is it responsible for the elastic properties of many cell types, but it also plays a vital role in cellular adhesion and motility. Understanding the bundling kinetics of actin filaments is important in the formation of various cytoskeletal structures, such as filopodia and stress fibers. Utilizing a unique pillar-structured microfluidic device, we investigated the time dependence of bundling kinetics of pillar supported free-standing actin filaments. Microparticles attached to the filaments allowed the measurement of thermal motion, and we found that bundling takes place at lower concentrations than previously found in 3-dimensional actin gels, i.e. actin filaments formed bundles in the presence of 5-12 mM of magnesium chloride in a time-dependent manner. The filaments also displayed long term stability for up to hours after removing the magnesium ions from the buffer, which suggests that there is an extensive hysteresis between cation induced crosslinking and decrosslinking.
Fluid-to-fluid modelling of critical heat flux in 37-element bundles
International Nuclear Information System (INIS)
The applicability of fluid-to-fluid modelling for critical heat flux (CHF) in 37-element bundles has been examined. CHF data obtained with 37-element bundle simulators from various Freon test programs at Chalk River Laboratories (CRL) were compared against those obtained from the water-test programs. The comparison was based on a transformation of the Freon parameters (i.e., pressure, mass flux and CHF) into water-equivalent values (no transformation is needed for dryout quality, which represents the non-dimensional value of enthalpy). In addition, this study examined the impact of axial heat-flux distribution and channel orientation on fluid-to-fluid modelling. At high-pressure and high-flow conditions of interest, the water-equivalent values of the Freon-test data closely represent the water-test data of uniformly and non-uniformly heated bundle strings for vertical and horizontal flows. The effects of axial heat-flux distribution and channel orientation on bundle CHF have also been closely simulated with Freon at conditions of interest. (author)
Minimal fixed point set of maps on Torus Fiber Bundles over the Circle
Silva, Weslem L.
2013-01-01
The main purpose this work is to study the minimal fixed point set of fiber-preserving maps for spaces which are fiber bundles over the circle and the fiber is the torus. Using the one-parameter fixed point theory is possible to describe these sets in terms of the fundamental group and the induced homomorphism.
Analysis of fuelling sequence and fatigue life for 4-bundle shift refuelling scheme in CANDU6 NPP
International Nuclear Information System (INIS)
A 4-bundle shift refuelling method of CANDU6 F/H (Fuel Handling) System is analyzed to assess the operational flexibility and capacity of F/H system. The current 8-bundle shift refuelling scheme requires to refuel eight fuel bundles from a single fuel channel, and to refuel 14 fuel channels in a week on average assuming that the reactor is in a steady state. The analysis showed that the 4-bundle shift refuelling method increases F/M (Fuelling Machine) duty cycle and operator load. However, the fuelling method change from the 8- to 4-bundle shift refuelling will not require additional team of operators. A marginal increase in the maintenance cost may be resulted in by the change of fuelling method and the increase of fatigue usage factors requires some components to be replaced during the F/M lifetime
International Nuclear Information System (INIS)
Innovative nuclear reactor concepts like accelerator driven systems (ADS) or the lead cooled fast reactor LFR employ lead bismuth eutectic (LBE) as a coolant. Within the framework of the EU project THINS (thermalhydraulics of innovative nuclear systems) a rod bundle experiment in LBE is performed employing characteristic dimensions at the Karlsruhe Liquid Metal Laboratory (KALLA)l of Karlsruhe Institute of Technology (KIT). In a first measurement campaign it is observed that the pressure drop across the first spacer in the rod bundle experiment is noticeable larger than at the subsequent spacers. We speculate that this is due to blockage of the very narrow spacer channels and numerically investigate whether there are substantially enhanced entrance effects. The present numerical study investigates the whole rod bundle including the entrance region in order to show possible mechanisms which can increase the pressure drop of the first spacer even if no blockage is present. The extra pressure loss compared to simulations with uniform inflow is found to be very small which supports the speculation of blockage. Since rod bundle flow is known to depend very sensitive on turbulence models and mesh resolution we carefully verify that our simulations use an adequate computation domain, mesh resolution and turbulence model. (author)
Assessment of CHF characteristics at subcooled conditions for the CANDU CANFLEX bundle
International Nuclear Information System (INIS)
An analysis has been performed to assess the Critical Heat Flux (CHF) characteristics for the CANFLEX bundle at subcooled conditions. CHF characteristics for CANDU bundles have been established from experiments using full-scale bundle simulators. These experiments covered flow conditions of interest to normal operation and postulated loss-of-flow and small break loss-of-coolant accidents. Experimental CHF values obtained from these experiments were applied to develop correlations for analyses of regional overpower protection and safety trips. These correlations are applicable to the saturated region in the reference uncrept channel and the slightly subcooled region in postulated high-creep channels. Expanding the CHF data to subcooled conditions facilitates the evaluation of the margin to dryout at upstream bundle locations, even though dryout occurrences are not anticipated there. In view of the lack of experimental data, the ASSERT-PV subchannel code has been applied to establish CHF values at low qualities and high subcoolings (thermodynamic qualities corresponding to -25%). These CHF values have been applied to extend the CHF correlation to the highly subcooled conditions. (author)
Analytical and CFD investigation of ex-core cooling of the nuclear fuel rod bundle in a water pool
International Nuclear Information System (INIS)
The efficiency of ex-core cooling of nuclear fuel assemblies under decay heat generation is influenced by many conditions, among them being coolant flow rate, position of fuel assemblies in a water pool, and position of coolant inlets and outlets. A combination of unacceptable thermal-hydraulic conditions occurred at the Nuclear Power Plant PAKS in Hungary in April 2003, during the process of nuclear fuel assembly chemical cleaning in a specially designed tank. The cooling of the nuclear fuel rod bundles in the tank was not efficient under low coolant flow rates through the cleaning tank, and after several hours the boiling of cooling water occurred with subsequent dry-out of nuclear fuel rod bundles. The thermal-hydraulic conditions in the cleaning tank that led to the unexpected event are analysed both analytically and with a CFD approach for idealized conditions of one nuclear fuel rod bundle with the bottom by-pass opening. The analytical analysis is based on a pressure balance of low Reynolds number upward water coolant flow through the bundle, downward water flow in the pool around the bundle, flow across the by-pass opening and outlet flow from the cleaning vessel. The transient CFD simulations are performed in order to demonstrate multidimensional effects of the event. The water density dependence on the temperature is taken into account in both analytical and CFD investigation, as the dominant effect that influences the buoyancy forces between the water flow streams inside and outside the vertically positioned bundle in the water pool. The influence of the bundle bottom by-pass area on the water pool thermal-hydraulic conditions and on the efficiency of the nuclear fuel rods cooling is analysed. Both analytical and CFD results show that the continuous cooling of the fuel rods can not be achieved for higher values of the bundle bottom by-pass areas. The averaged coolant temperature in the water pool outside the bundle becomes higher than the average
Using Product Bundling to Facilitate the Adoption Process of Radical Innovations
Reinders, M.J.; Frambach, R.T.; Schoormans, J.P.L.
2010-01-01
Generally, radical innovations are not easily adopted in the market. Potential adopters experience difficulties to comprehend and evaluate radical innovations due to their newness in terms of technology and benefits offered. Consequently, adoption intentions may remain low. This paper proposes bundl
Statistical fracture of E-glass fibres using a bundle tensile test and acoustic emission monitoring
R'Mili, M.; Moevus, M.; Godin, N.
2009-01-01
Statistical fracture of E-glass fibres using a bundle tensile test and acoustic emission monitoring correspondance: Corresponding author.Tel.: +33472436127; fax: +33472438528. (R?Mili, M.) (R?Mili, M.) Universite de Lyon--> , INSA-Lyon--> , MATEIS--> , 7 Avenue Jean Capelle--> , 69621 Villeurbanne Cedex--> - FRANCE (R?Mili, M.) Universite de Lyon--> , INSA-Lyo...
Advanced CFD simulations of turbulent flows around appendages in CANDU fuel bundles
International Nuclear Information System (INIS)
Computational Fluid Dynamics (CFD) was used to simulate the coolant flow in a modified 37-element CANDU fuel bundle, in order to investigate the effects of the appendages on the flow field. First, a subchannel model was created to qualitatively analyze the capabilities of different turbulence models such as k.ε, Reynolds Normalization Group (RNG), Shear Stress Transport (SST) and Large Eddy Simulation (LES). Then, the turbulence model with the acceptable quality was used to investigate the effects of positioning appendages, normally used in CANDU 37-element Critical Heat Flux (CHF) experiments, on the flow field. It was concluded that the RNG and SST models both show improvements over the k.ε method by predicting cross flow rates closer to those predicted by the LES model. Also the turbulence effects in the k.ε model dissipate quickly downstream of the appendages, while in the RNG and SST models appear at longer distances similar to the LES model. The RNG method simulation time was relatively feasible and as a result was chosen for the bundle model simulations. In the bundle model simulations it was shown that the tunnel spacers and leaf springs, used to position the bundles inside the pressure tubes in the experiments, have no measureable dominant effects on the flow field. The flow disturbances are localized and disappear at relatively short streamwise distances. (author)
Chung, Peter J.; Song, Chaeyeon; Deek, Joanna; Miller, Herbert P.; Li, Youli; Choi, Myung Chul; Wilson, Leslie; Feinstein, Stuart C.; Safinya, Cyrus R.
2016-01-01
Tau, an intrinsically disordered protein confined to neuronal axons, binds to and regulates microtubule dynamics. Although there have been observations of string-like microtubule fascicles in the axon initial segment (AIS) and hexagonal bundles in neurite-like processes in non-neuronal cells overexpressing Tau, cell-free reconstitutions have not replicated either geometry. Here we map out the energy landscape of Tau-mediated, GTP-dependent ‘active' microtubule bundles at 37 °C, as revealed by synchrotron SAXS and TEM. Widely spaced bundles (wall-to-wall distance Dw–w≈25–41 nm) with hexagonal and string-like symmetry are observed, the latter mimicking bundles found in the AIS. A second energy minimum (Dw–w≈16–23 nm) is revealed under osmotic pressure. The wide spacing results from a balance between repulsive forces, due to Tau's projection domain (PD), and a stabilizing sum of transient sub-kBT cationic/anionic charge–charge attractions mediated by weakly penetrating opposing PDs. This landscape would be significantly affected by charge-altering modifications of Tau associated with neurodegeneration. PMID:27452526
The Stochastic Grid Bundling Method :Efficient pricing of Bermudan options and their Greeks
Jain, S.; Oosterlee, C.W.
2015-01-01
This paper describes a practical simulation-based algorithm, which we call the Stochastic Grid Bundling Metho d(SGBM) for pricing multdimensional Bermudan (i.e.discretely exercisable) options. The method generates a direct estimator of the option price, an optimal early-exercise policy as well as a
Dam, P.M. van; Proniewska, K.; Maugenest, A.M.; Mieghem, N.M. van; Maan, A.C.; Jaegere, P.P. de; Bruining, N.
2014-01-01
AIMS: Conventional electrocardiogram (ECG)-based diagnosis of left bundle branch block (LBBB) in patients with left ventricular hypertrophy (LVH) is ambiguous. Left ventricular hypertrophy is often seen in patients with severe aortic stenosis in which a transcatheter aortic valve implantation (TAVI)
A burnout correlation for flow of boiling water in vertical rod bundles
International Nuclear Information System (INIS)
The rod bundle burnout correlation described in the present report is a development from our earlier published rod bundle correlation for low pressures. The correlation is based on the Becker round duct correlation and is written on the form xBO 0.68*η*ηL*XRD where xRD is the burnout steam quality in a round duc at corresponding flow conditions, η is the ratio of heated to total perimeter and ηl is a correction factor, which is a function of q/A only. It is demonstrated that this equation combined with the heat balance equation q/A = G/(4L/DH)*(ΔhSUB + XBO*Hfg) predicts the burnout heat fluxes for 312 measurements obtained in our laboratory within a scatter of ±7. 5 per cent and with an RMS error of 3.8 per cent. The measurements were obtained in the following ranges of variables. Number of rods n 1, 3, 6 and 7; Rod diameter di 10.05 - 13.80 mm; Shroud diameter do 17. 42 - 71. 0 mm; Rod clearance s 3.7 - 8.8 mm; Heated length L 608 - 4440 mm; Pressure p 20-71 kg/cm2, Inlet sub-cooling Δtsub 3 - 240 deg C; Mass velocity G 80-1,500 kg/m2; Burnout heat flux q/A 74-314 W/cm2; Burnout steam quality xBO 0. 1 - 0.55. The correlation shows that the burnout conditions in wide ranges of variables are independent of the inlet sub-cooling and the heated length, and that the effects of mass velocity and pressure are the same in rod bundles and in round tubes. It is also demonstrated that the effects of a radial heat flux variation within the rod bundle can be handled by the correlation by modifying the η-value for the bundle. The rod bundle data presented by Janssen and Kervinen, Hench, Obertelli, Matzner, Haslam, Edwards and Obertelli and Hench and Boehm were also analysed in terms of the measured and predicted burnout heat fluxes. These data covered bundles consisting of 3, 4, 6, 7, 9. 19 and 36 rods and it was found that a very good agreement existed between the present correlation and the measurements
Post-irradiation examination of CANDU MOX fuel bundle containing weapons grade plutonium
Energy Technology Data Exchange (ETDEWEB)
Dimayuga, F.C.; Karam, M.; Montin, J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)
2008-07-01
The Parallex Project is an experiment designed to demonstrate the feasibility of dispositioning US and Russian weapons grade plutonium (WPu) in CANDU reactors as a mixed-oxide (MOX) fuel. The Parallex Project involved the fabrication, irradiation testing, and post-irradiation examination (PIE) of three experimental CANDU MOX fuel bundles containing WPu fuel elements that were manufactured in the US and Russia. Some of the bundles contained MOX fuel fabricated at Chalk River Laboratories (CRL) from civilian plutonium (CivPu). This paper will describe the irradiation testing and post-irradiation examination of the second Parallex bundle. The second Parallex bundle is a 37-element bundle with its centre element removed to accommodate its irradiation in the National Research Universal (NRU) reactor. The bundle was assembled at CRL using intermediate and inner elements containing WPu MOX fuel pellets fabricated by the Bochvar Institute (Russia) and CivPu MOX pellets fabricated by AECL. The 18 outer elements were fuelled with natural uranium oxide fuel pellets containing dysprosia (to reduce the neutron flux that the Pu-bearing elements would be exposed to). Half of the intermediate and inner elements contained MOX fuel pellets fabricated with depleted uranium containing 4.6 wt% WPu. The other half of the intermediate and inner elements contained MOX fuel pellets fabricated with depleted uranium containing 5.3 wt% CivPu. The irradiation testing of the second bundle was completed in NRU. The intermediate MOX elements experienced linear powers up to 49 kW/m and achieved a burnup of 294 MWh/kgHE (12 MWd/kgHE). The inner MOX elements experienced linear powers up to 23 kW/m and achieved a burnup of 130 MWh/kgHE (5 Wd/kgHE). There was a significant difference between the performance of AECL-made MOX fuel containing CivPu and Russian MOX fuel containing WPu in terms of fission gas release (FGR). This is attributed to the different fabrication processes used to manufacture the
Lectures on moduli of principal G-bundles over algebraic curves
International Nuclear Information System (INIS)
These notes are supposed to be an introduction to the moduli of G-bundles on curves. Therefore I will lay stress on ideas in order to make these notes more readable. In the last years the moduli spaces of G-bundles over algebraic curves have attracted some attention from various subjects like from conformal field theory or Beilinson and Drinfeld's geometric Langlands program. In both subjects it turned out that the 'stacky' point of view is more convenient and as the basic motivation of these notes is to introduce to the latter subject our moduli spaces will be moduli stacks (and not coarse moduli spaces). As people may feel uncomfortable with stacks I have included a small introduction to them. Actually there is a forthcoming book of Laumon and Moret-Bailly based on their preprint and my introduction merely does the step -1, i.e. explains why we are forced to use them here and recalls the basic results I need later. So here is the plan of the lectures: after some generalities on G-bundles, I will classify them topologically. Actually the proof is more interesting than the result as it will give a flavor of the basic theorem on G-bundles which describes the moduli stack as a double quotient of loop-groups. This 'uniformization theorem', which goes back to A. Weil as a bijection on sets, will be proved in the section following the topological classification. Then I will introduce two line bundles on the moduli stack: the determinant and the paffian bundle. The first one can be used to describe the canonical bundle on the moduli stack and the second to define a square-root of it. Unless G is simply connected the square root depends on the choice of a theta-characteristic. This square root plays an important role in the geometric Langlands program. Actually, in order to get global differential operators on the moduli stack one has to consider twisted differential operators with values in these square-roots. The rest of the lectures will be dedicated to describe the
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...... men vs. 0.5%/2.3% in women, P <0.001). Significant predictors of newly acquired RBBB were male gender, increasing age, high systolic blood pressure, and presence of IRBBB, whereas predictors of newly acquired IRBBB were male gender, increasing age, and low BMI. Right bundle branch block was associated...... with significantly increased all-cause and cardiovascular mortality in both genders with age-adjusted hazard ratios (HR) of 1.31 [95% confidence interval (CI), 1.11-1.54] and 1.87 (95% CI, 1.48-2.36) in the gender pooled analysis with little attenuation after multiple adjustment. Right bundle branch...
The demonstration irradiation of the CANFLEX-NU fuel bundle in Wolsong NGS 1
International Nuclear Information System (INIS)
A demonstration irradiation (DI) of 24 CANFLEX-NU fuel bundles in the high power Q07 channel and low power L21 channel of Wolsong Power Generation Station-1 had been successfully conducted jointly by KEPRI/KHNP/KAERI in the period of 2002 July to 2004 January. The tracking of the reactor operation data showed that the reactor has been stably operated during the DI. One CANFLEX bundle irradiated in the Q07 channel had a typical history of high power and high burnup, where the maximum element linear power rating was ∼ 42 kW/m at the burnup of ∼ 50 MWh/kgU and ∼ 35 kW/m at the discharge element burnup of ∼ 210 MWh/kgU. While, another CANFLEX bundles also irradiated in the Q07 channel had a typical history of power ramping, where the maximum element power ramping-up or -down rate was 28 kW/m. The unusual performance and integrity of the CANFLEX elements could not be found in the ELESTRES predictions and also the in-bay visual examinations showed that all the bundles were intact, free of defects and appeared to be in good condition as expected. Therefore, it is concluded that the demonstration irradiation shows the validation of the CANFLEX bundle performance with direct conditions of relevance under the Korean licensing requirements and the KNFC fuel fabrication capability, and provides the rationale for the decision to perform the full-conversion of CANFLEX fuel in WPGS-1. (author)
Numerical simulation of the flow in a tight lattice SFR rod-bundle with grid spacers
International Nuclear Information System (INIS)
The accurate prediction of the flow in rod bundles is crucial for both the design and the safe operation of nuclear reactor systems. However the geometry complexity and the non-uniformity of the flow introduce peculiar features that can be reproduced only with three-dimensional CFD. In fact, even in bare rod bundles, i.e., bundles that do not contain any spacing device, the structure of the flow is inherently complex, due to the presence of a large-scale instability. Moreover, experimental analysis has clearly shown that when reducing the pitch-to-diameter ratio (P/D) the turbulence field in rod bundles deviates significantly from that in a circular tube. For extremely tight configurations the existence of large-scale coherent structures has been shown, which is responsible for the high inter-sub-channel heat and momentum exchange. While there is a fairly extensive literature on the presence of these structures in bare rod-bundles and simplified geometries, there are no available studies of their presence in geometry containing grid spacers or wires. A series of fully transient simulations of turbulence have been performed for an infinite tight triangular lattice (typical of current SFR designs) with and without a grid spacer. The simulations have been performed using Large Eddy Simulation (LES) with the spectral element code Nek5000 and unsteady Reynolds Averaged Navier-Stokes (URANS) for P/D=1.08. Several structure recognition techniques and statistical methods have been applied in order to investigate the flow field and the three-dimensional pattern of the coherent structures. The results prove that, for the configuration studied, coherent structures are indeed present and contribute significantly to the flow dynamics. (author)
The story of George Huntington and his disease
Directory of Open Access Journals (Sweden)
Kalyan B Bhattacharyya
2016-01-01
Full Text Available George Huntington described some families with choreiform movements in 1872 in the United States of America and since then many such families have been described in other parts of the world and works on the genetics of the disease have brought new vistas in the understanding of the disease. In 1958, Americo Negrette, a young Venezuelan physician observed similar subjects in the vicinity of Lake Maracaibo which was presented by his co-worker, Ramon Avilla Giron at New York in 1972 when United States of America had been commemorating the centenary year of Huntington′s disease. Nancy Wexler, a psychoanalyst, whose mother had been suffering from the disease attended the meeting and organized a research team to Venezuela and they systematically studied more than 18,000 individuals in order to work out a common pedigree. They identified the genetic locus of the disease in the short arm of chromosome 4 and observed that it was a trinucleotide repeat disorder.
Measurements of turbulent flows in a 2 × 2 rod bundle
International Nuclear Information System (INIS)
Turbulence models such as the k–ε model have been used in numerical predictions of turbulent flows in rod bundles. However, the validation of the turbulence models is not an easy task mainly due to the lack of experimental data on turbulent flows in rod bundles. In this study, we therefore measured three-dimensional velocity and turbulence intensities of water flows in a 2 × 2 rod bundle by using a particle image velocimetry (PIV) system. The diameter and pitch of the rods were 20 and 25 mm, respectively. The mean velocity ranged from 1 to 2 m/s. To measure the velocity distributions in the subchannels, the rod in the measurement region was made of fluorinated ethylene propylene (FEP) resin, the refractive index of which is almost the same as that of water. The time-averaged velocity and turbulent intensities at each measurement point were obtained from 10,000 instantaneous velocities. Time-series velocity distributions were also acquired to understand the motion of turbulence eddies in the subchannel. The experimental results indicate that the axial mean velocity along the line normal to the rod in the inner subchannel agrees well with the one-seventh power law, and that the velocity fluctuation in the direction normal to the rod wall becomes weak in the rod gap. Numerical simulations using the k–ε models were carried out to examine their applicability to the turbulent flow in the rod bundle. They gave reasonable predictions for the distribution of the axial velocity in the rod bundle and the flow rate in each subchannel.
Endfield, Georgina H.; Veale, Lucy; Hall, Alexander
2015-01-01
British climatologist and geographer, Gordon Manley (1902–1980), is perhaps best known for his pioneering work on climate variability in the UK, for establishing the Central England Temperature series and, for his pivotal role in demonstrating the powerful relationship between climate, weather, and culture in post-World War II Britain. Yet Manley made many contributions, both professional and popular, to climate change debates in the twentieth century, where climate change is broadly understo...
Beller Lecture: The Roots of Leo Szilard and his Interdisciplinarity
Marx, George
1998-04-01
A Central European among the whites was said about Leo Szilard who originated from a polycultural family. In the early 20th century he grew up in Hungary, at the crossroads of history, where political regimes, national borders, ideological doctrines, ``final truths'' changed in a dizzying cavalcade. Instead of conservative dogmatism this social environment required critical thinking in order to survive. World War I was the school of Theodore von Kármán, John von Neumann, Eugene P. Wigner and Leo Szilard; each of them learned trespassing political and disciplinary boundaries without inhibition. Their sensitivity for trends had been utilized by the United States when war efforts and high tech required orientation under new horizons. Szilard's interest ranged from statistical physics through information theory to biological evolution, from life phenomena through hot atoms to nuclear strategy. His intellectual adventures might look crazy jumps for specialists. But now, looking back to the political and technological history of the 20th century one can see than it was a consequent progress of a future-sensitive mind.
Multidisciplinary HIS DICOM interfaces at the Department of Veterans Affairs
Kuzmak, Peter M.; Dayhoff, Ruth E.
2000-05-01
The U.S. Department of Veterans Affairs (VA) is using the Digital Imaging and Communications in Medicine (DICOM) standard to integrate image data objects from multiple systems for use across the healthcare enterprise. DICOM uses a structured representation of image data and a communication mechanism that allows the VA to easily acquire images from multiple sources and store them directly into the online patient record. The VA can obtain both radiology and non- radiology images using DICOM, and can display them on low-cost clinician's color workstations throughout the medical center. High-resolution gray-scale diagnostic quality multi-monitor workstations with specialized viewing software can be used for reading radiology images. The VA's DICOM capabilities can interface six different commercial Picture Archiving and Communication Systems (PACS) and over twenty different image acquisition modalities. The VA is advancing its use of DICOM beyond radiology. New color imaging applications for Gastrointestinal Endoscopy and Ophthalmology using DICOM are under development. These are the first DICOM offerings for the vendors, who are planning to support the recently passed DICOM Visible Light and Structured Reporting service classes. Implementing these in VistA is a challenge because of the different workflow and software support for these disciplines within the VA HIS environment.
Directory of Open Access Journals (Sweden)
Sandra Sánchez-García
2015-08-01
Full Text Available Aim of the study: The objective of this study was to evaluate recent technological improvements to forest bundlers: a new cutting device with shears and a mechanism which allows the bundling pressure to be changed by the driver. Area of study: eucalyptus plantations in Northern Spain. Material and Methods: Several time studies were performed in order to compare and calculate productivity depending on the machine: John Deere bundler working with the traditional chainsaw and Monra bundler equipped with the technological improvements of shears and adjustable bundling pressure. Research highlights: Significant differences were found between cutting devices (shears and chainsaw and between the Monra working at maximum pressure and at lower pressure. Shears were shown to be a more robust and reliable cutting device, with 1.02 cutting attempts per bundle compared to 1.55 with chain saw. The use of shears made the loading more efficient as it eliminates the need to shake the residues before feeding the bundler. A great advantage of this technological improvement is that it can be incorporated into other machines and thus improve bundling efficiency. In spite of this, working at standard bundling pressure, the productivity of the Monra bundler is only 3.2 per cent higher than that of the John Deere due to the fact that in the latter bundling is faster and it produces bundles with significantly more dry mass. For the Monra bundler, the option of producing lighter bundles further reduced productivity compared to when standard weight bundles are produced. However, it would be of interest to study the effect of the machine working at various pressures in order to optimize the work system. It is possible that working at higher pressures would have advantages in terms of increasing transport efficiency.