International Nuclear Information System (INIS)
Kawahara, Akimaro; Sadatomi, Michio; Higuchi, Tatsuya
2009-01-01
Two-phase diversion cross-flow between tight lattice subchannels has been investigated experimentally and analytically. For hydraulically non-equilibrium flows with the pressure difference between the subchannels, experiments were conducted using a vertical multiple-channel with two subchannels simplifying a triangle tight lattice rod bundle. To know the effects of the reduced surface tension on the diversion cross-flow, water and water with a surfactant were used as the test liquids. Data were obtained on the axial variations in the pressure difference between the subchannels, gas and liquid flow rates and void fraction in each subchannel for slug-churn and annular flows. In the analysis, flow redistribution processes due to the diversion cross-flow have been calculated by our subchannel analysis code based on a two-fluid model. From a comparison between the experiment and the code calculation, the code was found to be valid against the present data if the improved constitutive equations of wall and interfacial friction reported in our previous paper were incorporated to account for the reduced surface tension effects. (author)
Lattice QCD inputs to the CKM unitarity triangle analysis
International Nuclear Information System (INIS)
Laiho, Jack; Lunghi, E.; Van de Water, Ruth S.
2010-01-01
We perform a global fit to the Cabibbo-Kobayashi-Maskawa unitarity triangle using the latest experimental and theoretical constraints. Our emphasis is on the hadronic weak matrix elements that enter the analysis, which must be computed using lattice QCD or other nonperturbative methods. Realistic lattice QCD calculations which include the effects of the dynamical up, down, and strange quarks are now available for all of the standard inputs to the global fit. We therefore present lattice averages for all of the necessary hadronic weak matrix elements. We attempt to account for correlations between lattice QCD results in a reasonable but conservative manner: whenever there are reasons to believe that an error is correlated between two lattice calculations, we take the degree of correlation to be 100%. These averages are suitable for use as inputs both in the global Cabibbo-Kobayashi-Maskawa unitarity triangle fit and other phenomenological analyses. In order to illustrate the impact of the lattice averages, we make standard model predictions for the parameters B-circumflex K , |V cb |, and |V ub |/|V cb |. We find a (2-3)σ tension in the unitarity triangle, depending upon whether we use the inclusive or exclusive determination of |V cb |. If we interpret the tension as a sign of new physics in either neutral kaon or B mixing, we find that the scenario with new physics in kaon mixing is preferred by present data.
Topological chiral phonons in center-stacked bilayer triangle lattices
Xu, Xifang; Zhang, Wei; Wang, Jiaojiao; Zhang, Lifa
2018-06-01
Since chiral phonons were found in an asymmetric two-dimensional hexagonal lattice, there has been growing interest in the study of phonon chirality, which were experimentally verified very recently in monolayer tungsten diselenide (2018 Science 359 579). In this work, we find chiral phonons with nontrivial topology in center-stacked bilayer triangle lattices. At the Brillouin-zone corners, (), circularly polarized phonons and nonzero phonon Berry curvature are observed. Moreover, we find that the phonon chirality remain robust with changing sublattice mass ratio and interlayer coupling. The chiral phonons at the valleys are demonstrated in doubler-layer sodium chloride along the [1 1 1] direction. We believe that the findings on topological chiral phonons in triangle lattices will give guidance in the study of chiral phonons in real materials and promote the phononic applications.
Experimental study on reflooding in advanced tight lattice PWR
International Nuclear Information System (INIS)
Hori, K.; Kodama, J.; Teramae, T.
2000-01-01
This paper is related to the experimental study on the feasibility of core cooling by re-flooding in a large break loss of coolant accident (LOCA) for the advanced tight lattice pressurized water reactor (PWR). The tight lattice core design should be adopted to improve the conversion ratio. Major one of the key questions of such tight lattice core is the cooling capability under the re-flood condition in a large break LOCA. Forced feed bottom re-flooding experiments have been performed by use of a 4x4 triangular array rod bundle. The rod gap is 0.5 mm, 1.0 mm, or 1.5 mm. The measured peak temperature is below around 1273 K even in case of 1.0/0.5 mm rod gap. And, the evaluation based on the experimental results of rod temperatures and core pressure drop also shows that the core cooling under re-flooding condition is feasible. (author)
Numerical simulation of flow behavior in tight lattice rod bundle
International Nuclear Information System (INIS)
Yu Yiqi; Yang Yanhua; Gu Hanyang; Cheng Xu; Song Xiaoming; Wang Xiaojun
2009-01-01
The Numerical investigation is performed on the air turbulent flow in triangular rod bundle array. Based on the experimental data, the eddy viscosity turbulent model and the Reynold stress turbulent model are evaluated to simulate the flow behavior in the tight lattice. The results show that SSG Reynolds Stress Model has shown superior predictive performance than other Reynolds-stress models, which indicates that the simulation of the anisotropy of the turbulence is significant in the tight lattice. The result with different Reynolds number and geometry shows that the magnitude of the secondary flow is almost independent of the Reynolds number, but it increases with the decrease of the P/D. (authors)
Critical heat flux experiments in tight lattice core
Energy Technology Data Exchange (ETDEWEB)
Kureta, Masatoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
2002-12-01
Fuel rods of the Reduced-Moderation Water Reactor (RMWR) are so designed to be in tight lattices as to reduce moderation and achieve higher conversion ratio. As for the BWR type reactor coolant flow rate is reduced small compared with the existing BWR, so average void fraction comes to be langer. In order to evaluate thermo hydraulic characteristics of designed cores, critical heat flux experiments in tight lattice core have been conducted using simulated high pressure coolant loops for both the PWR and BWR seven fuel rod bundles. Experimental data on critical heat flux for full bundles have been accumulated and applied to assess the critical power of designed cores using existing codes. Evaluated results are conservative enough to satisfy the limiting condition. Further experiments on axial power distribution effects and 37 fuel rod bundle tests will be performed to validate thermohydraulic characteristics of designed cores. (T. Tanaka)
Critical heat flux experiments in tight lattice core
International Nuclear Information System (INIS)
Kureta, Masatoshi
2002-01-01
Fuel rods of the Reduced-Moderation Water Reactor (RMWR) are so designed to be in tight lattices as to reduce moderation and achieve higher conversion ratio. As for the BWR type reactor coolant flow rate is reduced small compared with the existing BWR, so average void fraction comes to be langer. In order to evaluate thermo hydraulic characteristics of designed cores, critical heat flux experiments in tight lattice core have been conducted using simulated high pressure coolant loops for both the PWR and BWR seven fuel rod bundles. Experimental data on critical heat flux for full bundles have been accumulated and applied to assess the critical power of designed cores using existing codes. Evaluated results are conservative enough to satisfy the limiting condition. Further experiments on axial power distribution effects and 37 fuel rod bundle tests will be performed to validate thermohydraulic characteristics of designed cores. (T. Tanaka)
Tight-binding tunneling amplitude of an optical lattice
International Nuclear Information System (INIS)
Arzamasovs, Maksims; Liu, Bo
2017-01-01
The particle in a periodic potential is an important topic in an undergraduate quantum mechanics curriculum and a stepping stone on the way to more advanced topics, such as courses on interacting electrons in crystalline solids, and graduate-level research in solid-state and condensed matter physics. The interacting many-body phenomena are usually described in terms of the second quantized lattice Hamiltonians which treat single-particle physics on the level of tight-binding approximation and add interactions on top of it. The aim of this paper is to show how the tight-binding tunneling amplitude can be related to the strength of the periodic potential for the case of a cosine potential used in the burgeoning field of ultracold atoms. We show how to approach the problem of computing the tunneling amplitude of a deep lattice using the JWKB (Jeffreys–Wentzel–Kramers–Brillouin, also known as semiclassical) approximation. We also point out that care should be taken when applying the method of the linear combination of atomic orbitals (LCAO) in an optical lattice context. A summary of the exact solution in terms of Mathieu functions is also given. (paper)
Tight-binding tunneling amplitude of an optical lattice
Arzamasovs, Maksims; Liu, Bo
2017-11-01
The particle in a periodic potential is an important topic in an undergraduate quantum mechanics curriculum and a stepping stone on the way to more advanced topics, such as courses on interacting electrons in crystalline solids, and graduate-level research in solid-state and condensed matter physics. The interacting many-body phenomena are usually described in terms of the second quantized lattice Hamiltonians which treat single-particle physics on the level of tight-binding approximation and add interactions on top of it. The aim of this paper is to show how the tight-binding tunneling amplitude can be related to the strength of the periodic potential for the case of a cosine potential used in the burgeoning field of ultracold atoms. We show how to approach the problem of computing the tunneling amplitude of a deep lattice using the JWKB (Jeffreys-Wentzel-Kramers-Brillouin, also known as semiclassical) approximation. We also point out that care should be taken when applying the method of the linear combination of atomic orbitals (LCAO) in an optical lattice context. A summary of the exact solution in terms of Mathieu functions is also given.
Impact of Heterogeneity and Lattice Bond Strength on DNA Triangle Crystal Growth.
Stahl, Evi; Praetorius, Florian; de Oliveira Mann, Carina C; Hopfner, Karl-Peter; Dietz, Hendrik
2016-09-07
One key goal of DNA nanotechnology is the bottom-up construction of macroscopic crystalline materials. Beyond applications in fields such as photonics or plasmonics, DNA-based crystal matrices could possibly facilitate the diffraction-based structural analysis of guest molecules. Seeman and co-workers reported in 2009 the first designed crystal matrices based on a 38 kDa DNA triangle that was composed of seven chains. The crystal lattice was stabilized, unprecedentedly, by Watson-Crick base pairing. However, 3D crystallization of larger designed DNA objects that include more chains such as DNA origami remains an unsolved problem. Larger objects would offer more degrees of freedom and design options with respect to tailoring lattice geometry and for positioning other objects within a crystal lattice. The greater rigidity of multilayer DNA origami could also positively influence the diffractive properties of crystals composed of such particles. Here, we rationally explore the role of heterogeneity and Watson-Crick interaction strengths in crystal growth using 40 variants of the original DNA triangle as model multichain objects. Crystal growth of the triangle was remarkably robust despite massive chemical, geometrical, and thermodynamical sample heterogeneity that we introduced, but the crystal growth sensitively depended on the sequences of base pairs next to the Watson-Crick sticky ends of the triangle. Our results point to weak lattice interactions and high concentrations as decisive factors for achieving productive crystallization, while sample heterogeneity and impurities played a minor role.
Infinite projected entangled-pair state algorithm for ruby and triangle-honeycomb lattices
Jahromi, Saeed S.; Orús, Román; Kargarian, Mehdi; Langari, Abdollah
2018-03-01
The infinite projected entangled-pair state (iPEPS) algorithm is one of the most efficient techniques for studying the ground-state properties of two-dimensional quantum lattice Hamiltonians in the thermodynamic limit. Here, we show how the algorithm can be adapted to explore nearest-neighbor local Hamiltonians on the ruby and triangle-honeycomb lattices, using the corner transfer matrix (CTM) renormalization group for 2D tensor network contraction. Additionally, we show how the CTM method can be used to calculate the ground-state fidelity per lattice site and the boundary density operator and entanglement entropy (EE) on an infinite cylinder. As a benchmark, we apply the iPEPS method to the ruby model with anisotropic interactions and explore the ground-state properties of the system. We further extract the phase diagram of the model in different regimes of the couplings by measuring two-point correlators, ground-state fidelity, and EE on an infinite cylinder. Our phase diagram is in agreement with previous studies of the model by exact diagonalization.
Pressure drop characteristics in tight-lattice bundles for reduced-moderation water reactors
International Nuclear Information System (INIS)
Tamai, Hidesada; Kureta, Masatoshi; Yoshida, Hiroyuki; Akimoto, Hajime
2004-01-01
The reduced-moderation water reactor (RMWR) consists of several distinctive structures; a triangular tight-lattice configuration and a double-flat core. In order to design the RMWR core from the point of view of thermal-hydraulics, an evaluation method on pressure drop characteristics in the rod bundles at the tight-lattice configuration is required. In this study, calculated results by the Martinelli-Nelson's and Hancox's correlations were compared with experimental results in 4 x 5 rod bundles and seven-rod bundles. Consequently, the friction loss in two-phase flows becomes smaller at the tight-lattice configuration with the hydraulic diameter less than about 3 mm. This reason is due to the difference of the configuration between the multi-rod bundle and the circular tube and due to the effect of the small hydraulic diameter on the two-phase multiplier. (author)
Critical heat flux in tubes and tight hexagonal rod lattices
International Nuclear Information System (INIS)
Erbacher, F.J.; Cheng Xu; Zeggel, W.
1994-01-01
The critical heat flux (CHF) in small-diameter tubes and in tight hexagonal 7-rod and 37-rod bundles was investigated in the KRISTA test facility, using Freon 12 as the working fluid. The measurements in tubes showed that the influence of the tube diameter on CHF cannot be described as suggested by earlier publications with sufficient accuracy. CHF in bundles is lower than in tubes under comparable conditions. The influence of spacers (grid spacers, wire wraps) on CHF was found to be governed by local steam qualities. A comparison of the test results with some CHF prediction methods showed that the look-up table method reproduces the test results in circular tubes most accurately. Combined with CHF look-up tables, subchannel analysis and Ahmad's fluid-to-fluid scaling law, Freon experiments have proven to be a suitable tool for CHF prediction in water-cooled rod bundles. (orig.) [de
Subchannel analysis of 37-rod tight-lattice bundle experiments for reduced-moderation water reactor
International Nuclear Information System (INIS)
Nakatsuka, Toru; Tamai, Hidesada; Akimoto, Hajime
2005-01-01
R and D project to investigate thermal-hydraulic performance of tight-lattice fuel bundles for Reduced-Moderation Water Reactor (RMWR) started at Japan Atomic Energy Research Institute (JAERI) in collaboration with utilities, reactor vendors and universities from 2002. The RMWR realizes a high conversion ratio larger than 0.1 for sustainable energy supply through plutonium multiple recycling based on the well-experienced LWR technologies. The reactor core comprises tight-lattice fuel assemblies with gap clearance of around 1.0 mm to reduce the water volume ratio to achieve the high conversion ratio. A problem of utmost importance from a thermal-hydraulic point of view is the coolability of the tight-lattice assembly with such a small gap width. JAERI has been carrying out experimental study to investigate the system parameter effects on the thermal-hydraulic performance and to confirm the feasibility of the core. In the present study, the subchannel analysis code NASCA was applied to 37-rod tight-lattice bundle experiments. The NASCA can give good predictions of critical power for the gap width of 1.3 mm while the prediction accuracy decreases for the gap width of 1.0 mm. To improve the prediction accuracy, the code will be modified to take the effect of film thickness distribution around fuel rods on boiling transition. (author)
Study of minor actinides transmutation in heavy water cooled tight-pitch lattice
International Nuclear Information System (INIS)
Xu Xiaoqin; Shiroya, S.
2002-01-01
Minor actinides inhere long half-life and high toxicity. It is an alternative technical pathway and helpful for reducing environmental impact to incinerate minor actinides in spent fuel of nuclear power plants. Because of its high neutron, γ and β emitting rates and heat generation rate, it is necessary to imply more severe control and shielding techniques in the chemical treatment and fabrication. From economic view-point, it is suitable to transmute minor actinides in concentrated way. A technique for MA transmutation by heavy water cooled tight-pitch lattice system is proposed, and calculated with SRAC95 code system. It is shown that tight-pitch heavy water lattice can transmute MA effectively. The accelerator-driven subcritical system is practical for MA transmutation because of its low fraction of effective delay neutrons
Energy Technology Data Exchange (ETDEWEB)
Saxena, Abhishek, E-mail: asaxena@lke.mavt.ethz.ch [ETH Zurich, Laboratory for Nuclear Energy Systems, Department of Mechanical and Process Engineering, Sonneggstrasse 3, 8092 Zürich (Switzerland); Zboray, Robert [Laboratory for Thermal-hydraulics, Nuclear Energy and Safety Department, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland); Prasser, Horst-Michael [ETH Zurich, Laboratory for Nuclear Energy Systems, Department of Mechanical and Process Engineering, Sonneggstrasse 3, 8092 Zürich (Switzerland); Laboratory for Thermal-hydraulics, Nuclear Energy and Safety Department, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland)
2016-04-01
High conversion light water reactors (HCLWR) having triangular, tight-lattice fuels bundles could enable improved fuel utilization compared to present day LWRs. However, the efficient cooling of a tight lattice bundle has to be still proven. Major concern is the avoidance of high-quality boiling crisis (film dry-out) by the use of efficient functional spacers. For this reason, we have carried out experiments on adiabatic, air-water annular two-phase flows in a tight-lattice, triangular fuel bundle model using generic spacers. A high-spatial-resolution, non-intrusive measurement technology, cold neutron tomography, has been utilized to resolve the distribution of the liquid film thickness on the virtual fuel pin surfaces. Unsteady CFD simulations have also been performed to replicate and compare with the experiments using the commercial code STAR-CCM+. Large eddies have been resolved on the grid level to capture the dominant unsteady flow features expected to drive the liquid film thickness distribution downstream of a spacer while the subgrid scales have been modeled using the Wall Adapting Local Eddy (WALE) subgrid model. A Volume of Fluid (VOF) method, which directly tracks the interface and does away with closure relationship models for interfacial exchange terms, has also been employed. The present paper shows first comparison of the measurement with the simulation results.
Critical power characteristics in 37-rod tight lattice bundles under transient conditions
International Nuclear Information System (INIS)
Liu, Wei; Kureta, Masatoshi; Tamai, Hidesada; Ohnuki, Akira; Akimoto, Hajime
2007-01-01
Critical power characteristics in the postulated abnormal transient processes that may be possibly met in the operation of Innovative Water Reactor for Flexible Fuel Cycle (FLWR) were investigated for the design of the FLWR core. Transient Boiling Transition (BT) tests were carried out using two sets of 37-rod tight lattice rod bundles (rod diameter: 13 mm; rod clearance: 1.3 mm or 1.0 mm) at Japan Atomic Energy Agency (JAEA) under the conditions covering the FLWR operating condition (P ex =7.2 MPa, T in =556 K) for mass velocity G=400-800 kg/(m 2 s). For the postulated power increase and flow decrease transients, no obvious change of the critical power against the steady one was observed. The traditional quasi-steady characteristic was confirmed to be working for the postulated power increase and flow decrease transients. The experiments were analyzed with TRAC-BF1 code, where the JAEA newest critical power correlation for the tight lattice rod bundles was implemented for the BT judgment. The TRAC-BF1 code showed good prediction for the occurrence or the non occurrence of the BT and for the exact BT starting time. The tranditional quasi-steady state prediction of the BT in transient process was confirmed to be applicable for the postulated abnormal transient processes in the tight lattice rod bundles. (author)
Thorium Fuel Performance in a Tight-Pitch Light Water Reactor Lattice
International Nuclear Information System (INIS)
Kim, Taek Kyum; Downar, Thomas J.
2002-01-01
Research on the utilization of thorium-based fuels in the intermediate neutron spectrum of a tight-pitch light water reactor (LWR) lattice is reported. The analysis was performed using the Studsvik/Scandpower lattice physics code HELIOS. The results show that thorium-based fuels in the intermediate spectrum of tight-pitch LWRs have considerable advantages in terms of conversion ratio, reactivity control, nonproliferation characteristics, and a reduced production of long-lived radiotoxic wastes. Because of the high conversion ratio of thorium-based fuels in intermediate spectrum reactors, the total fissile inventory required to achieve a given fuel burnup is only 11 to 17% higher than that of 238 U fertile fuels. However, unlike 238 U fertile fuels, the void reactivity coefficient with thorium-based fuels is negative in an intermediate spectrum reactor. This provides motivation for replacing 238 U with 232 Th in advanced high-conversion intermediate spectrum LWRs, such as the reduced-moderator reactor or the supercritical reactor
Physics Colloquium - Tight-binding in a new light: Photons in optical lattices
Ecole de Physique - Université de Genève
2011-01-01
Geneva University Physics Department 24, Quai Ernest Ansermet CH-1211 Geneva 4 Lundi 21 mars 2011, 17h00 Ecole de Physique, Auditoire Stueckelberg Tight-binding in a new light: Photons in optical lattices Dr. Niels Madsen Department of Physics, Swansea University, Singleton Park, Swansea, United Kingdom Antihydrogen, the bound state of an antiproton and a positron, has been produced at low energies at CERN (the European Organization for Nuclear Research) since 2002. Antihydrogen is of interest for use in a precision test of nature's fundamental symmetries. The charge conjugation/parity/time reversal (CPT) theorem, a crucial part of the foundation of the standard model of elementary particles and interactions, demands that hydrogen and antihydrogen have the same spectrum. Given the current experimental precision of measurements on the hydrogen atom, subjecting antihydrogen to rigorous spectroscopic examination would constitute a compelling, model-independent test of CPT. Antihydrogen co...
Measurement of vapor behavior in tight-lattice bundles by neutron radiography
International Nuclear Information System (INIS)
Kureta, Masatoshi; Akimoto, Hajime
2004-01-01
Three-dimensional and instantaneous void fractions in tight-lattice 7-rod and 14-rod bundles were measured by neutron radiography in order to make clear the flow behavior and to verify the advanced fine-mesh numerical analysis codes for the R and D of the Reduced-Moderation Water Reactors (RMWR). Time-averaged 3D void fraction distribution is evaluated with the spatial resolution of 0.1 - 0.2 mm using neutron tomography, and consecutive change of vapor behavior is observed quantitatively with time step of 1 ms using high-frame-rate neutron radiography (HFR-NR). In this paper, void fraction distribution and vapor behavior of flow boiling of water in tight-lattice rod bundles are focused on and discussed based on the obtained results. 'High void fraction spot', 'void drift phenomenon', and 'vapor chimney' were observed under atmospheric pressure conditions. Here, 'high void fraction spot' indicates that high void fraction regions are appeared between adjacent rods, narrow space, at/near point of net vapor generation region. 'Void drift' and 'vapor chimney' represent that high void fraction region moves to wide triangular space and is formed a vapor flow channel so-called 'vapor chimney'. It was confirmed from the time-averaged 3D data that void fraction in the center is higher than that in the periphery. On the other hand, it was found from the HFR-NR experiments that big vapor bubbles and/or cluster flow upward intermittently not only in the center but in the periphery of the channel and, therefore, point of net vapor generation is scattered statistically in wide region. (author)
Development of a transverse mixing model for large scale impulsion phenomenon in tight lattice
International Nuclear Information System (INIS)
Liu, Xiaojing; Ren, Shuo; Cheng, Xu
2017-01-01
Highlights: • Experiment data of Krauss is used to validate the feasibility of CFD simulation method. • CFD simulation is performed to simulate the large scale impulsion phenomenon for tight-lattice bundle. • A mixing model to simulate the large scale impulsion phenomenon is proposed based on CFD result fitting. • The new developed mixing model has been added in the subchannel code. - Abstract: Tight-lattice is widely adopted in the innovative reactor fuel bundles design since it can increase the conversion ratio and improve the heat transfer between fuel bundles and coolant. It has been noticed that a large scale impulsion of cross-velocity exists in the gap region, which plays an important role on the transverse mixing flow and heat transfer. Although many experiments and numerical simulation have been carried out to study the impulsion of velocity, a model to describe the wave length, amplitude and frequency of mixing coefficient is still missing. This research work takes advantage of the CFD method to simulate the experiment of Krauss and to compare experiment data and simulation result in order to demonstrate the feasibility of simulation method and turbulence model. Then, based on this verified method and model, several simulations are performed with different Reynolds number and different Pitch-to-Diameter ratio. By fitting the CFD results achieved, a mixing model to simulate the large scale impulsion phenomenon is proposed and adopted in the current subchannel code. The new mixing model is applied to some fuel assembly analysis by subchannel calculation, it can be noticed that the new developed mixing model can reduce the hot channel factor and contribute to a uniform distribution of outlet temperature.
The NEPTUN experiments on LOCA thermal-hydraulics for tight-lattice PWRs
International Nuclear Information System (INIS)
Dreier, J.; Chawla, R.; Rouge, N.; Yanar, S.
1990-01-01
The NEPTUN test facility at the Paul Scherrer Institute is currently being used to provide a broad data base for the validation of thermal-hydraulics codes used in predicting the reflooding behaviour of a tight-lattice PWR (light water highb conversion reactor, LWHCR). The present paper gives a description of the facility and the matrix to be covered in the experimental program. Results are presented from a number of forced-feed, bottom-reflooding experiments, comparisons being made with (a) measurements carried out earlier for standard-PWR geometry and (b) the results of a calculational benchmark exercise conducted in the framework of a Swiss/German LWHCR-development agreement. Rewetting for the tight, hexagonal-geometry (p/d = 1.13) NEPTUN-III test bundle has been found to occur in all tests carried out to date, in which reasonably LWHCR-representative values for the various thermal-hydraulics parameters are used. Results of the calculational benchmark exercise have confirmed the need for further code development efforts for achieving reliable predictions of LWHCR reflooding behaviour. (author) 11 figs., 3 tabs., 3 refs
International Nuclear Information System (INIS)
Dalle Donne, M.; Hame, W.
1982-12-01
A parametric thermohydraulic study for an Advanced Pressurized Light Water Reactor (APWR) with a tight fuel rod lattice has been performed. The APWR improves the uranium utilisation. The APWR core should be placed in a modern German PWR plant. Within this study about 200 different reactors have been calculated. The tightening of the fuel rod lattice implies a decrease of the net electrical output of the plant, which is greater for the heterogeneous reactor than for the homogeneous reactor. APWR cores mean higher core pressure drops and higher water velocities in the core region. The cores tend to be shorter and the number of fuel rods to be higher than for the PWR. At the higher fuel rod pitch to diameter ratios (p/d) the DNB limitation is more stringent than the limitation on the fuel rod linear rating given by the necessity of reflooding after a reactor accident. The contrary is true for the lower p/d ratios. Subcooled boiling in the highest rated coolant channels occurs for the most of the calculated reactors. (orig.) [de
Critical power experiment with a tight-lattice 37-rod bundle
International Nuclear Information System (INIS)
Kureta, Masatoshi; Tamai, Hidesada; Ohnuki, Akira; Sato, Takashi; Liu, Wei; Akimoto, Hajime
2006-01-01
Since most of critical power or CHF data have been collected in tube, annulus, or BWR geometries under BWR flow conditions, critical power data for highly tight and triangular lattice bundles under low mass velocity are indispensable for thermal-hydraulic design of Reduced-Moderation Water Reactor. Large-scale thermal-hydraulic experiments which use a basic 37-rod bundle test section (rod diameter: 13.0 mm, gap width between rods: 1.3 mm) were therefore carried out in this study within range of 2-9 MPa in pressure and 150-1,000 kg/(m 2 ·s) in mass velocity. Fundamental characteristics of boiling transition were investigated through effects of flow parameter on critical power and those of rod number. It was confirmed that the fundamental characteristics in 37-rod bundle are similar to those in 7-rod bundle and in case of the BWR geometry. The results of the transverse non-uniform power distribution test and subchannel analysis suggest that the critical power becomes higher when the transverse local quality distribution closes to uniform. (author)
Measurement and CFD calculation of spacer loss coefficient for a tight-lattice fuel bundle
International Nuclear Information System (INIS)
In, Wang Kee; Shin, Chang Hwan; Kwack, Young Kyun; Lee, Chi Young
2015-01-01
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 × 10 4 –2 × 10 5 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 × 10 5
International Nuclear Information System (INIS)
Ohnuki, A.; Kureta, M.; Liu, W.; Tamai, H.; Akimoto, H.
2004-01-01
Research and development project for investigating thermal-hydraulic performance in tight-lattice rod bundles for Reduced-Moderation Water Reactor (RMWR) started at Japan Atomic Energy Research Institute (JAERI) in 2002. The RMWR can attain the favorable characteristics such as effective utilization of uranium resources, multiple recycling of plutonium, high burn-up and long operation cycle, based on matured light-water reactor technologies. MOX fuel assemblies with tight lattice arrangement are used to increase the conversion ratio by reducing the moderation of neutron. Increasing the in-core void fraction also contributes to the reduction of neutron moderation. The confirmation of thermal-hydraulic feasibility is one of the most important issues for the RMWR because of the tight-lattice configuration. The project has mainly consisted of a large-scale thermal-hydraulic test and development of analytical methods named modeling engineering. In the large-scale test, 37-rod bundle experiments can be performed. Steady-state critical power experiments have been achieved in the test facility and the experimental data reveal the feasibility of RMWR
Zhang, Weizhong; Yoshida, Hiroyuki; Ose, Yasuo; Ohnuki, Akira; Akimoto, Hajime; Hotta, Akitoshi; Fujimura, Ken
In relation to the design of an innovative FLexible-fuel-cycle Water Reactor (FLWR), investigation of thermal-hydraulic performance in tight-lattice rod bundles of the FLWR is being carried out at Japan Atomic Energy Agency (JAEA). The FLWR core adopts a tight triangular lattice arrangement with about 1 mm gap clearance between adjacent fuel rods. In view of importance of accurate prediction of cross flow between subchannels in the evaluation of the boiling transition (BT) in the FLWR core, this study presents a statistical evaluation of numerical simulation results obtained by a detailed two-phase flow simulation code, TPFIT, which employs an advanced interface tracking method. In order to clarify mechanisms of cross flow in such tight lattice rod bundles, the TPFIT is applied to simulate water-steam two-phase flow in two modeled subchannels. Attention is focused on instantaneous fluctuation characteristics of cross flow. With the calculation of correlation coefficients between differential pressure and gas/liquid mixing coefficients, time scales of cross flow are evaluated, and effects of mixing section length, flow pattern and gap spacing on correlation coefficients are investigated. Differences in mechanism between gas and liquid cross flows are pointed out.
International Nuclear Information System (INIS)
Akira Ohnuki; Kazuyuki Takase; Masatoshi Kureta; Hiroyuki Yoshida; Hidesada Tamai; Wei Liu; Toru Nakatsuka; Hajime Akimoto
2005-01-01
R and D project to investigate thermal-hydraulic performance in tight-lattice rod bundles for Reduced-Moderation Water Reactor (RMWR) is started at Japan Atomic Energy Research Institute in collaboration with power company, reactor vendors, universities since 2002. The RMWR can attain the favorable characteristics such as effective utilization of uranium resources, multiple recycling of plutonium, high burn-up and long operation cycle, based on matured LWR technologies. MOX fuel assemblies with tight lattice arrangement are used to increase the conversion ratio by reducing the moderation of neutron. Increasing the in-core void fraction also contributes to the reduction of neutron moderation. The confirmation of thermal-hydraulic feasibility is one of the most important R and D items for the RMWR because of the tight-lattice configuration. In this paper, we will show the R and D plan and describe some advances on experimental and analytical studies. The experimental study is performed mainly using large-scale (37-rod bundle) test facility and the analytical one aims to develop a predictable technology for geometry effects such as gap between rods, grid spacer configuration etc. using advanced 3-D two-phase flow simulation methods. Steady-state and transient critical power experiments are conducted with the test facility (Gap width between rods: 1.0 mm) and the experimental data reveal the feasibility of RMWR. (authors)
International Nuclear Information System (INIS)
Lee, Chiyoung; Kwack, Youngkyun; Park, Juyong; Shin, Changhwan; In, Wangkee
2013-01-01
Our research group has investigated the effect of P/D difference on the behavior of turbulent rod bundle flow without the mixing vane spacer grid, using PIV (Particle Image Velocimetry) and MIR (Matching Index of Refraction) techniques for tight lattice fuel rod bundle application. In this work, using the tight-lattice rod bundle with a twist-mixing vane spacer grid, the turbulent rod bundle flow is preliminarily examined to validate the PIV measurement and CFD (Computational Fluid Dynamics) simulation. The turbulent flow in the tight-lattice rod bundle with a twist-mixing vane spacer grid was preliminarily examined to validate the PIV measurement and CFD simulation. Both were in agreement with each other within a reasonable degree of accuracy. Using PIV measurement and CFD simulation tested in this work, the detailed investigations on the behavior of turbulent rod bundle flow with the twist-mixing vane spacer grid will be performed at various conditions, and reported in the near future
International Nuclear Information System (INIS)
Araya, Fumimasa; Nakatsuka, Toru; Yoritsune, Tsutomu
2002-10-01
In order to improve plutonium utilization, design studies of reduced moderation water reactors which have hard neutron energy spectrum have been carried out at Division of Energy System Research of Japan Atomic Energy Research Institute (JAERI). At present, triangle, tight pitch lattice cores with about 1 mm gap width between fuel rods have been focused in the neutronic core design. Since a degradation of the heat removal from the fuel rods is worried, an evaluation of heat removal capability i.e. critical heat flux becomes one of important evaluation items in the feasibility study. However, any of published data base, which can be applicable to the evaluation on such narrow gap width cores, does not exist. Therefore, in the present study, in order to accumulate applicable data and to confirm applicability of an evaluation methodology of critical heat flux, basic experiments on the critical heat flux were performed using the test sections consisted of 7 heater rods bundles with the gap widths of 1.5, 1.0 and 0.6 mm under the PWR pressure conditions. The present report describes the experimental apparatus, experimental conditions and accumulated data. Analysis results of the data and the applicability of the evaluation methodology used for the design work are also discussed in this report. As the results of the experiment, it was found that the critical heat flux increased as the mass flux and the inlet subcooling increased. In the region of the mass flux less than about 2,000 kg/m 2 /s, the critical heat flux decreased as the gap width decreased. In the larger mass flux region, obvious trend of effects of the gap width on critical heat flux were not observed due to data scatterings. The flow-area-averaged thermal-equilibrium quality at the CHF position was in the higher ranges from 0.3 to 0.8 in the cases of gap widths of 1.0 and 0.6 mm, and 0.1 to 0.3 in the 1.5 mm case. Based on the experimental results such that the CHFs occurred in the higher quality range and
CHF-KFK-3: A critical heat flux correlation for triangular arrays of rods with tight lattices
International Nuclear Information System (INIS)
Dalle Donne, M.
1991-02-01
High converting PWR's (HCPWR or APWR) are based on fuel elements with rods placed in a tight lattice triangular array. The CHF correlation development previously at KfK for such geometry (CHF-KFK-2 correlation) has been tested against recently performed experiments. The comparison with the Siemens-KWU experiments with rod clusters with spacer grid and six integral spiral ribs supports has allowed to improve and extended the previous correlation. A new correlation, called CHF-KFK-3, which accounts for these improvements, is presented in the paper. (orig.) [de
International Nuclear Information System (INIS)
Li Juan; Wang Yifei; Gong Changde
2011-01-01
We consider the tight-binding models of electrons on a two-dimensional triangular lattice and kagome lattice under staggered modulated magnetic fields. Such fields have two components: a uniform-flux part with strength φ, and a staggered-flux part with strength Δφ. Various properties of the Hall conductances and Hofstadter butterflies are studied. When φ is fixed, variation of Δφ leads to the quantum Hall transitions and Chern numbers of Landau subbands being redistributed between neighboring pairs. The energy spectra with nonzero Δφs have similar fractal structures but quite different energy gaps compared with the original Hofstadter butterflies of Δφ = 0. Moreover, the fan-like structure of Landau levels in the low magnetic field region is also modified appreciably by Δφ.
Energy Technology Data Exchange (ETDEWEB)
Li Juan; Wang Yifei; Gong Changde, E-mail: yfwang_nju@hotmail.com [Center for Statistical and Theoretical Condensed Matter Physics, and Department of Physics, Zhejiang Normal University, Jinhua 321004 (China)
2011-04-20
We consider the tight-binding models of electrons on a two-dimensional triangular lattice and kagome lattice under staggered modulated magnetic fields. Such fields have two components: a uniform-flux part with strength {phi}, and a staggered-flux part with strength {Delta}{phi}. Various properties of the Hall conductances and Hofstadter butterflies are studied. When {phi} is fixed, variation of {Delta}{phi} leads to the quantum Hall transitions and Chern numbers of Landau subbands being redistributed between neighboring pairs. The energy spectra with nonzero {Delta}{phi}s have similar fractal structures but quite different energy gaps compared with the original Hofstadter butterflies of {Delta}{phi} = 0. Moreover, the fan-like structure of Landau levels in the low magnetic field region is also modified appreciably by {Delta}{phi}.
Analysis of Seven NEPTUN-III (Tight-Lattice) Bottom-Flooding Experiments with RELAP5/MOD3.3/BETA
International Nuclear Information System (INIS)
Analytis, G.Th.
2004-01-01
Seven tight-lattice NEPTUN-III bottom-flooding experiments are analyzed by using the frozen version of RELAP5, RELAP5/MOD3.3/BETA. This work is part of the Paul Scherrer Institute (PSI) contribution to the High Performance Light Water Reactor (HPLWR) European Union project and aims at assessing the capabilities of the code to model the reflooding phenomena in a tight hexagonal lattice (which was one of the core geometries considered at the time for an HPLWR) following a hypothetical loss-of-coolant accident scenario. Even though the latest version of the code has as a default the new PSI reflood model developed by the author, which was tested and assessed against reflooding data obtained at standard light water reactor lattices, this work shows that for tight lattices, the code underpredicts the peak clad temperatures measured during a series of reflooding experiments performed at the NEPTUN-III tight-lattice heater rod bundle facility. The reasons for these differences are discussed, and the (possible) changes needed in the framework of RELAP5/MOD3.3 for improving the modeling of reflooding in tight lattices are investigated
Neutronic investigations of an equilibrium core for a tight-lattice light water reactor
International Nuclear Information System (INIS)
Broeders, C.H.M.
1992-01-01
Calculation procedures and first results concerning the neutronic design of an equilibrium core of an advanced pressurized water reactor (APWR) with mixed oxide fuel in a compact light water moderated triangular lattice are presented. Principle and qualification of the cell burnup calculations with the KARBUS program are briefly discussed. The fuel assembly design with single control rod positions filled with control rod material or coolant water requires special transport theory calculations, which are performed with a one-dimensional supercell model. The macroscopic fuel assembly cross section data is collected in a special library to be used in a new calculational procedure, ARCOSI, for multi-cycle reactor core simulations. Its first application for a reference design resulted in an equilibrium configuration with moderator density reactivity coefficients which are satisfactory as regards safety. (orig.) [de
International Nuclear Information System (INIS)
Ohnuki, A.; Kureta, M.; Takae, K.; Tamai, H.; Akimoto, H.; Yoshida, H.
2004-01-01
The research project to investigate thermal-hydraulic performance in tight-lattice rod bundles for Reduced-Moderation Water Reactor (RMWR) started at Japan Atomic Energy Research Institute (JAERI) in 2002. The RMWR is a light water reactor for which a higher conversion ratio more than one can be expected. In order to attain this higher conversion ratio, triangular tight-lattice fuel bundles whose gap spacing between each fuel rod is around 1 mm are required. As for the thermal design of the RMWR core, conventional analytical methods are no good because the conventional composition equations can not predict the RMWR core with high accuracy. Then, development of new quantitative analytical procedures was carried out. Those analytical procedures are constructed by model experiments and advanced two-phase flow analysis codes. This paper describes the results of the model experiments and analytical results with the developed analysis codes. (authors)
Ohnuki, Akira; Kureta, Masatoshi; Yoshida, Hiroyuki; Tamai, Hidesada; Liu, Wei; Misawa, Takeharu; Takase, Kazuyuki; Akimoto, Hajime
R&D project to investigate thermal-hydraulic performance in tight-lattice rod bundles for Innovative Water Reactor for Flexible Fuel Cycle has been progressed at Japan Atomic Energy Agency in collaboration with power utilities, reactor vendors and universities since 2002. In this series-study, we will summarize the R&D achievements using large-scale test facility (37-rod bundle with full-height and full-pressure), model experiments and advanced numerical simulation technology. This first paper described the master plan for the development of design technology and showed an executive summary for this project up to FY2005. The thermal-hydraulic characteristics in the tight-lattice configuration were investigated and the feasibility was confirmed based on the experiments. We have developed the design technology including 3-D numerical simulation one to evaluate the effects of geometry/scale on the thermal-hydraulic behaviors.
Scott, Paul
2006-01-01
A lattice is a (rectangular) grid of points, usually pictured as occurring at the intersections of two orthogonal sets of parallel, equally spaced lines. Polygons that have lattice points as vertices are called lattice polygons. It is clear that lattice polygons come in various shapes and sizes. A very small lattice triangle may cover just 3…
International Nuclear Information System (INIS)
Liu, Wei; Tamai, Hidesada; Kureta, Masatoshi; Ohnuki, Akira; Takase, Kazuyuki; Akimoto, Hajime
2007-01-01
A thermal-hydraulic feasibility project for an Innovative Water Reactor for Flexible fuel cycle (FLWR) has been performed since 2002. In this R and D project, large-scale thermal-hydraulic tests, several model experiments and development of advanced numerical analysis codes have been carried out. In this paper, we will describe the critical power characteristics in a 37-rod tight-lattice bundle with rod-bowing under both steady and transient states. It is observed that no matter it is run under a steady or a transient state, boiling transition (BT) always occurs axially at exit elevation of upper high-heat-flux region and transversely in the central area of the bundle. Steady critical power increases monotonically with the increase of mass velocity, with the decrease of inlet water temperature and with the decrease of exit pressure. These trends are same as those in the base case test without rod-bowing. The steady critical power with rod-bowing is about 10% lower than that without rod-bowing. For the postulated power increase and flow decrease cases that may be possibly met in a normal operation of the FLWR, it is confirmed that no BT occurs when Initial Critical Power Ratio (ICPR) is 1.3. Moreover, when the transitions are run under severer ICPR that causes BT, the transient critical powers are generally same as the steady ones. The experiments are analyzed with TRAC-BF1 code. The TRAC-BF1 code shows good prediction for the occurrence or the non occurrence of the BT and predicts the BT starting time within the accuracy of critical power correlation. Traditional quasi - steady state prediction of the transient BT is confirmed being applicable for the postulated abnormal transient processes in the tight lattice bundle with rod - bowing. (author)
International Nuclear Information System (INIS)
Yoshida, Hiroyuki; Takase, Kazuyuki; Suzuki, Takayuki
2009-01-01
Two-fluid model can simulate two-phase flow by computational cost less than detailed two-phase flow simulation method such as interface tracking method or particle interaction method. Therefore, two-fluid model is useful for thermal hydraulic analysis in large-scale domain such as a rod bundle. Japan Atomic Energy Agency (JAEA) develops three dimensional two-fluid model analysis code ACE-3D that adopts boundary fitted coordinate system in order to simulate complex shape flow channel. In this paper, boiling two-phase flow analysis in a tight-lattice rod bundle was performed by the ACE-3D. In the results, the void fraction, which distributes in outermost region of rod bundle, is lower than that in center region of rod bundle. The tendency of void fraction distribution agreed with the measurement results by neutron radiography qualitatively. To evaluate effects of two-phase flow model used in the ACE-3D, numerical simulation of boiling two-phase in tight-lattice rod bundle with no lift force model was also performed. In the results, the lift force model has direct effects on void fraction concentration in gap region, and pressure distribution in horizontal plane induced by void fraction distribution cause of bubble movement from the gap region to the subchannel region. The predicted pressure loss in the section that includes no spacer accorded with experimental results with around 10% of differences. The predicted friction pressure loss was underestimated around 20% of measured values, and the effect of the turbulence model is considered as one of the causes of this underestimation. (author)
International Nuclear Information System (INIS)
Ishikawa, Nobuyuki; Okubo, Tsutomu
2009-01-01
The time-domain analyses with TRAC-BF1 code were performed for clarifying the dynamical response characteristics of the reduced-moderation water reactor (RMWR) with tight-lattice core configuration. The response characteristics were evaluated based on the step response basically utilized for dynamical system evaluation. As for the most fundamental dynamical characteristics, the channel flow response characteristics of single fuel assembly were evaluated. In the evaluation, the appropriate single-phase pressure drop setting at the inlet orifice was determined in terms of response stability from the design viewpoint. In addition, from the investigation on the relation of the response and transit time of coolant, it is confirmed that the channel flow response of RMWR is dominated by the transit time of vapor phase resulting from a high void fraction operation condition. As for a natural circulation flow response, it is clarified that the response is strongly influenced by the effect of two-phase pressure loss owing to a high void fraction condition. The reactor power response with reactivity feedback shows quite stable response characteristics on account of the small absolute value of void reactivity coefficient.
International Nuclear Information System (INIS)
Mitsutake, Toru; Misawa, Takeharu; Kureta, Masatoshi; Akimoto, Hajime
2005-06-01
In tight-lattice simulated rod bundles with about 1 mm gap between rods, a rod displacement might affect thermal-hydraulic characteristics since the displacement has a strong impact on the flow area change along the heated section. It should be important to estimate how large the rod position displacement could quantitatively affect critical power for the tight-lattice rod bundle from the point of improvement of prediction capability of subchannel analysis. In the present study, the inside-structure observation of the simulated seven-rod bundle of Reduced Moderation Water Reactor (RMWR) was made through the whole length of the test assembly. Based on the measured rod position data, the relation between the rod position displacement and the heat transfer characteristics was investigated experimentally and through the two kinds of subchannel analysis, the nominal rod position case and the measured rod position case, the effect on the predicted critical power was estimated. The high-energy X-ray computer tomograph (CT) of Fuels Monitoring Facilities (FMF) at the O-arai Engineering Center in Japan Nuclear Cycle Institute (JNC) was applied for the inside-structure observation of the test assembly. The CT view of the cross sections within the test assembly assured the hexagonal rod position arrangement was almost the same as expected by design. The measured data with the X-ray CT facility showed that all rod displacements were small, 0.5 millimeters at maximum and 0.2 millimeters in average. In the heat transfer experiments for the seven-rod bundle, the boiling transition (BT) position and the rod surface temperature behavior was measured. All thermocouples on the center rod downstream from the BT-onset axial height showed almost simultaneous temperature increase due to BT. And the thermocouples located on the same axial heights showed quite similar time-variation behaviors in the vapor cooling heat transfer regime. These results demonstrated the effect of the
Vortex lattices in layered superconductors
International Nuclear Information System (INIS)
Prokic, V.; Davidovic, D.; Dobrosavljevic-Grujic, L.
1995-01-01
We study vortex lattices in a superconductor--normal-metal superlattice in a parallel magnetic field. Distorted lattices, resulting from the shear deformations along the layers, are found to be unstable. Under field variation, nonequilibrium configurations undergo an infinite sequence of continuous transitions, typical for soft lattices. The equilibrium vortex arrangement is always a lattice of isocell triangles, without shear
International Nuclear Information System (INIS)
Kureta, Masatoshi; Tamai, Hidesada; Liu, Wei; Akimoto, Hajime; Sato, Takashi; Watanabe, Hironori; Ohnuki, Akira
2006-03-01
Japan Atomic Energy Agency has been performing tight-lattice rod bundle thermal-hydraulic tests to realize essential technologies for the technological and engineering feasibility of super high burn-up water-cooled breeder reactor featured by a high breeding ratio and super high burn-up by reducing the core water volume in water-cooled reactor. The tests are performing to make clear the fundamental subjects related to the boiling transition (BT) (Subjects: BT criteria under a highly tight-lattice rod bundle, effects of gap-width between rods and of rod-bowing) using 37-rod bundles (Base case test section (1.3mm gap-width), Two parameter effect test sections (Gap-width effect one (1.0mm) and Rod-bowing one)). In the present report, we summarize the test results from the base case test section. The thermal-hydraulic characteristics using the large scale test section were obtained for the critical power, the pressure drop and the wall heat transfer under a wide range of pressure, flow rate, etc. including normal operational conditions of the designed reactor. Effects of local peaking factor on the critical power were also obtained. (author)
International Nuclear Information System (INIS)
Tamai, Hidesada; Kureta, Masatoshi; Liu, Wei; Akimoto, Hajime; Sato, Takashi; Watanabe, Hironori; Ohnuki, Akira
2006-11-01
Japan Atomic Energy Agency has been performing tight-lattice rod bundle thermal-hydraulic tests to realize essential technologies for the technological and engineering feasibility of super high burn-up water-cooled breeder reactor featured by a high breeding ratio and super high burn-up by reducing the core water volume in water-cooled reactor. The tests are performing to make clear the fundamental subjects related to the boiling transition (BT) (Subjects: BT criteria under a highly tight-lattice rod bundle, effects of gap-width between rods and of rod-bowing) using 37-rod bundles (Base case test section (1.3mm gap-width), Two parameter effect test sections (Gap-width effect one (1.0mm) and Rod-bowing one)). In the present report, we summarize the test results from the gap-width effect test section. The thermal-hydraulic characteristics were obtained for the critical power under the steady-state and transient conditions, the pressure drop and the wall heat transfer within a wide range of pressure, flow rate, etc. including normal operational conditions of the designed reactor. Then the gap-width effects were also obtained from the comparison between the results using the base case test section and the gap-width effect one. (author)
Graphing trillions of triangles.
Burkhardt, Paul
2017-07-01
The increasing size of Big Data is often heralded but how data are transformed and represented is also profoundly important to knowledge discovery, and this is exemplified in Big Graph analytics. Much attention has been placed on the scale of the input graph but the product of a graph algorithm can be many times larger than the input. This is true for many graph problems, such as listing all triangles in a graph. Enabling scalable graph exploration for Big Graphs requires new approaches to algorithms, architectures, and visual analytics. A brief tutorial is given to aid the argument for thoughtful representation of data in the context of graph analysis. Then a new algebraic method to reduce the arithmetic operations in counting and listing triangles in graphs is introduced. Additionally, a scalable triangle listing algorithm in the MapReduce model will be presented followed by a description of the experiments with that algorithm that led to the current largest and fastest triangle listing benchmarks to date. Finally, a method for identifying triangles in new visual graph exploration technologies is proposed.
Directory of Open Access Journals (Sweden)
Adrian Amarița
2016-01-01
Full Text Available Launch of the euro in the late 90s, can be interpreted as a first step towards the monetarysystem outlined by Mundell. Economists have noted the incompatibility of fixed exchange regime,perfect mobility of capital and the independence of monetary policy, the so-called triangle ofincompatibility, which was highlighted by Robert Mundell since 1968. Tommaso Padoa - Schioppacontinued his research on the harmonization and convergence required to economic policies in“Financial Europe". The author shows that the triangle is the freedom of movement of capital, theexchange rate stability and the autonomy of national monetary policies. The triangle ofincompatibility stems from the fact that they can be combined in their entirety, but only two. Theautonomy of monetary policy is the freedom of states to choose the appropriate monetary policyand take appropriate measures in case of recessions.
Anaïs Schaeffer
2012-01-01
The Italian National Institute for Nuclear Physics (INFN) has successfully tested the first model of a new fast-ramping curved dipole magnet. This is great news for CERN, which sees the advance as holding potential for the future of the SPS. The first model of a new fast-ramping curved dipole magnet being prepared for cryogenic testing at the LASA laboratory (INFN Milano, Italy). On 16 July INFN introduced an innovative dipole magnet. With a length of some 4 metres, it can produce a 4.5 Tesla magnetic field and achieve a tighter bend than ever before (the bending radius has been squeezed to a remarkable 66.7 metres). This new magnet was designed in the first instance for GSI’s SIS300 synchrotron (in Germany), which will require 60 dipoles of this type. "Achieving such a tight bend demanded a major R&D effort," stressed Pasquale Fabbricatore, the spokesman of the INFN collaboration responsible for the magnet’s development. "We had to not o...
Triangle in a triangle : on a problem of Steinhaus
Post, K.A.
1993-01-01
A necessary and sufficient condition on the sidesp, q, r of a trianglePQR and the sidesa, b, c of a triangleABC in order thatABC contains a congruent copy ofPQR is the following: At least one of the 18 inequalities obtained by cyclic permutation of {a, b, c} and arbitrary permutation of {itp, q, r}
Leptonic unitary triangles and boomerangs
International Nuclear Information System (INIS)
Dueck, Alexander; Rodejohann, Werner; Petcov, Serguey T.
2010-01-01
We review the idea of leptonic unitary triangles and extend the concept of the recently proposed unitary boomerangs to the lepton sector. Using a convenient parametrization of the lepton mixing, we provide approximate expressions for the side lengths and the angles of the six different triangles and give examples of leptonic unitary boomerangs. Possible applications of the leptonic unitary boomerangs are also briefly discussed.
The CKM matrix and the unitarity triangle
International Nuclear Information System (INIS)
Battaglia, M.; Buras, A.J.; Gambino, P.; Stocchi, A.; Abbaneo, D.; Ali, A.; Amaral, P.; Andreev, V.; Artuso, M.; Barberio, E.; Bauer, C.; Becirevic, D.; Beneke, M.; Bigi, I.; Bozzi, C.; Brandt, T.; Buchalla, G.; Calvi, M.; Cassel, D.; Cirigliano, V.; Ciuchini, M.
2003-01-01
This report contains the results of the Workshop on the CKM Unitarity Triangle that was held at CERN on 13-16 February 2002. There had been several Workshops on B physics that concentrated on studies at e + e - machines, at the Tevatron, or at LHC separately. Here we brought together experts of different fields, both theorists and experimentalists, to study the determination of the CKM matrix from all the available data of K, D, and B physics. The analysis of LEP data for B physics is reaching its end, and one of the goals of the Workshop was to underline the results that have been achieved at LEP, SLC, and CESR. Another goal was to prepare for the transfer of responsibility for averaging B physics properties, that has developed within the LEP community, to the present main actors of these studies, from the B factory and the Tevatron experiments. The optimal way to combine the various experimental and theoretical inputs and to fit for the apex of the Unitarity Triangle has been a contentious issue. A further goal of the Workshop was to bring together the proponents of different fitting strategies, and to compare their approaches when applied to the same inputs. Since lattice QCD plays a very important role in the determination of the non-perturbative parameters needed to constrain the CKM unitarity triangle, the first Workshop was seen as an excellent opportunity to bring together lattice theorists with the aim of establishing a working group to compile averages for phenomenologically relevant quantities. Representatives from lattice collaborations around the world were invited to attend a meeting during the Workshop. A consensus was reached to set up three test working groups, collectively known as the 'CKM Lattice Working Group', to review a number of well-studied quantities: quark masses, the kaon B-parameter, and the matrix elements relevant for neutral B-meson mixing. These proceedings are organized as a coherent document with chapters covering the domains of
The CKM Matrix and the unitarity triangle
International Nuclear Information System (INIS)
Battaglia, M.
2003-01-01
This report contains the results of the Workshop on the CKM Unitarity Triangle that was held at CERN on 13-16 February 2002. There had been several Workshops on B physics that concentrated on studies at e + e - machines, at the Tevatron, or at LHC separately. Here we brought together experts of different fields, both theorists and experimentalists, to study the determination of the CKM matrix from all the available data of K, D, and B physics. The analysis of LEP data for B physics is reaching its end, and one of the goals of the Workshop was to underline the results that have been achieved at LEP, SLC, and CESR. Another goal was to prepare for the transfer of responsibility for averaging B physics properties, that has developed within the LEP community, to the present main actors of these studies, from the B factory and the Tevatron experiments. The optimal way to combine the various experimental and theoretical inputs and to fit for the apex of the Unitarity Triangle has been a contentious issue. A further goal of the Workshop was to bring together the proponents of different fitting strategies, and to compare their approaches when applied to the same inputs. Since lattice QCD plays a very important role in the determination of the non-perturbative parameters needed to constrain the CKM unitarity triangle, the first Workshop was seen as an excellent opportunity to bring together lattice theorists with the aim of establishing a working group to compile averages for phenomenologically relevant quantities. Representatives from lattice collaborations around the world were invited to attend a meeting during the Workshop. A consensus was reached to set up three test working groups, collectively known as the ''CKM Lattice Working Group'', to review a number of well-studied quantities: quark masses, the kaon B-parameter, and the matrix elements relevant for neutral B-meson mixing. These proceedings are organized as a coherent document with chapters covering the domains
International Nuclear Information System (INIS)
Misawa, Takeharu; Ohnuki, Akira; Katsuyama, Kozo; Nagamine, Tsuyoshi; Nakamura, Yasuo; Akimoto, Hajime; Mitsutake, Toru; Misawa, Susumu
2007-01-01
Design studies of the Innovative Water Reactor for Flexible Fuel Cycle (FLWR) are being carried out at the Japan Atomic Energy Agency (JAEA) as one candidate for the future reactors. In actual core design, it is precondition to prevent fuel rods contact due to fuel rod bowing. However, the FLWR cores have nonconventional characteristics such as a hexagonal tight lattice arrangement and a high enrichment fuel loading. Therefore, as conservative evaluation, it is important to investigate influence of fuel rod bowing upon the boiling transition. In the JAEA, a 37-rod bundle experiments (base case test section (1.3mm gap width), gap width effect test section (1.0mm gap width), and rod bowing test section) were performed in order to investigate the thermal hydraulic characteristics in the tight lattice bundle. In this paper, the rod bowing effect test is paid attention. It is suspected that the actual fuel rod positions in the rod bowing test section may be different from the design-based positions. Even a slight displacement from the design-based position of fuel rod may occur variation of flow area, and give influence upon the thermal hydraulic characteristics in the rod bundle. Therefore, if the critical power in the rod bundle is evaluated by an analytical approach, the analysis based on more correct input can be performed by using actual fuel rod position data. In this study, the rod positions in the rod bowing test section were measured using the high energy X-ray computer tomography (Xray-CT). Based on the measured rod positions data, the subchannel analysis by the NASCA code was performed, in order to investigate applicability of the NASCA code to BT estimation of the rod bowing test section, and influence of displacement from design-based rod position upon BT estimation by the NASCA code. The predicted critical powers are agreement with those obtained by the experiment. The analysis based on the design-based rod positions is also performed, and the result is
Seismic interpretation of the triangle zone at Jumping Pound, Alberta
Energy Technology Data Exchange (ETDEWEB)
Slotboom, R. T. [Amerada Hess Canada Ltd., Calgary, AB (Canada); Lawton, D. C.; Spratt, D. A. [Calgary Univ., AB (Canada). Dept. of Geology and Geophysics
1996-06-01
The triangle zone at Jumping Point, Alberta was characterized using seismic survey data as a NW-SE-trending antiformal stack of thrust sheets involving Cretaceous rocks that have been wedged into the foreland between two detachments. Three major thrust sheets of Lower and Upper Cretaceous strata have been stacked to form the main extremity of the wedge. The structure is tightly folded at Jumping Point, and broadens northwest along the strike. 13 refs., 8 figs.
Antonella Del Rosso
2012-01-01
In the theory of the Standard Model, the masses, interactions and physical states of quarks – the basic constituents of matter – are described mathematically by a matrix known as the Cabibbo-Kobayashi-Maskawa (CKM) matrix. Three angles enter into the definition of the elements of the matrix. If their sum is not 180°, new physics might be the reason. A typical LHCb event during the recent proton-lead ion run. The LHCb experiment at CERN has measured precisely for the first time at a hadron collider one of the three angles - the “gamma” angle – so far known with the largest uncertainty. It’s a matter of angles: if their sum is not exactly 180°, the geometric shape is not a triangle. And if the angles are those related to the CKM matrix, we enter the realm of physics beyond the Standard Model. Experiments at B-factories have measured the three angles – α, β and γ &...
Triangles: Shapes in Math, Science and Nature.
Ross, Catherine Sheldrick
This book examines everything having to do with the triangle. It begins with a basic definition of the triangle and continues with discussions on tetrahedrons, triangular prisms, and pyramid shapes. Some ideas addressed include how triangles are used to measure heights and distances, the importance of triangles to builders, Alexander Graham Bell's…
A mechanism for the downturn in inverse susceptibility in triangle-based frustrated spin systems
International Nuclear Information System (INIS)
Isoda, M
2008-01-01
A mechanism for the downturn of inverse magnetic susceptibility below an intermediate temperature, recently observed in many experiments, is proposed as an intrinsic feature of lattices with triangle-based frustrated geometries. The temperature at the bending of the inverse susceptibility curve may be related to the features of other thermodynamic properties; the hump of the specific heat and the emergence of a 1/3 plateau in magnetization under a magnetic field. This fact is derived through a Monte Carlo simulation study of the Ising model on triangular and kagome lattices, and the exact calculation for the single and small-sized triangle clusters, on both the Ising and Heisenberg models. These results may indicate the dominance of S(S z ) = 1/2 quantum (classical) trimer formation in the intermediate-energy regime in two-dimensional triangle-based lattices
DEFF Research Database (Denmark)
Lemvig, Jakob; Miller, Christopher; Okoudjou, Kasso A.
2014-01-01
to suggest effective analysis and synthesis computation strategies for such frames. Finally, we describe all prime frames constructed from the spectral tetris method, and, as a byproduct, we obtain a characterization of when the spectral tetris construction works for redundancies below two.......We introduce a class of finite tight frames called prime tight frames and prove some of their elementary properties. In particular, we show that any finite tight frame can be written as a union of prime tight frames. We then characterize all prime harmonic tight frames and use thischaracterization...
Visualizing Elections Using Saari Triangles
Alfaro, Ricardo; Han, Lixing; Schilling, Kenneth; Birgen, Mariah
2010-01-01
Students sometimes have difficulty calculating the result of a voting system applied to a particular set of voter preference lists. Saari triangles offer a way to visualize the result of an election and make this calculation easier in the case of several important voting systems.
Multigrid for refined triangle meshes
Energy Technology Data Exchange (ETDEWEB)
Shapira, Yair
1997-02-01
A two-level preconditioning method for the solution of (locally) refined finite element schemes using triangle meshes is introduced. In the isotropic SPD case, it is shown that the condition number of the preconditioned stiffness matrix is bounded uniformly for all sufficiently regular triangulations. This is also verified numerically for an isotropic diffusion problem with highly discontinuous coefficients.
Frustrated lattices of Ising chains
International Nuclear Information System (INIS)
Kudasov, Yurii B; Korshunov, Aleksei S; Pavlov, V N; Maslov, Dmitrii A
2012-01-01
The magnetic structure and magnetization dynamics of systems of plane frustrated Ising chain lattices are reviewed for three groups of compounds: Ca 3 Co 2 O 6 , CsCoCl 3 , and Sr 5 Rh 4 O 12 . The available experimental data are analyzed and compared in detail. It is shown that a high-temperature magnetic phase on a triangle lattice is normally and universally a partially disordered antiferromagnetic (PDA) structure. The diversity of low-temperature phases results from weak interactions that lift the degeneracy of a 2D antiferromagnetic Ising model on the triangle lattice. Mean-field models, Monte Carlo simulation results on the static magnetization curve, and results on slow magnetization dynamics obtained with Glauber's theory are discussed in detail. (reviews of topical problems)
On Generalizations of the Stirling Number Triangles
Lang, Wolfdieter
2000-09-01
Sequences of generalized Stirling numbers of both kinds are introduced. These sequences of triangles (i.e. infinite-dimensional lower triangular matrices) of numbers will be denoted by S2(k;n,m) and S1(k;n,m) with k in Z. The original Stirling number triangles of the second and first kind arise when k = 1. S2(2;n,m) is identical with the unsigned S1(2;n,m) triangle, called S1p(2;n,m), which also represents the triangle of signless Lah numbers. Certain associated number triangles, denoted by s2(k;n,m) and s1(k;n,m), are also defined. Both s2(2;n,m) and s1(2;n + 1, m + 1) form Pascal's triangle, and s2(-1,n,m) turns out to be Catalan's triangle. Generating functions are given for the columns of these triangles. Each S2(k) and S1(k) matrix is an example of a Jabotinsky matrix. Therefore the generating functions for the rows of these triangular arrays constitute exponential convolution polynomials. The sequences of the row sums of these triangles are also considered. These triangles are related to the problem of obtaining finite transformations from infinitesimal ones generated by x^k d/dx, for k in Z.
Nasal Soft-Tissue Triangle Deformities.
Foda, Hossam M T
2016-08-01
The soft-tissue triangle is one of the least areas attended to in rhinoplasty. Any postoperative retraction, notching, or asymmetries of soft triangles can seriously affect the rhinoplasty outcome. A good understanding of the risk factors predisposing to soft triangle deformities is necessary to prevent such problems. The commonest risk factors in our study were the wide vertical domal angle between the lateral and intermediate crura, and the increased length of intermediate crus. Two types of soft triangle grafts were described to prevent and treat soft triangle deformities. The used soft triangle grafts resulted in an excellent long-term aesthetic and functional improvement. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
The Weimar Triangle and The Ukrainian Crisis
Directory of Open Access Journals (Sweden)
Jean-Christophe Romer
2014-12-01
Full Text Available The article analyzes the activity of Weimar Triangle (Germany, France, Poland during Ukrainian crisis (2013-2014 as an efficient, but still largely underestimated negotiation force of the European Union. The evolution of role of Weimar Triangle in post-bipolar era is indicated, as well as the role of this specific structure during Ukrainian crisis.
Altitude, Orthocenter of a Triangle and Triangulation
Directory of Open Access Journals (Sweden)
Coghetto Roland
2016-03-01
Full Text Available We introduce the altitudes of a triangle (the cevians perpendicular to the opposite sides. Using the generalized Ceva’s Theorem, we prove the existence and uniqueness of the orthocenter of a triangle [7]. Finally, we formalize in Mizar [1] some formulas [2] to calculate distance using triangulation.
Circumcenter, Circumcircle and Centroid of a Triangle
Coghetto Roland
2016-01-01
We introduce, using the Mizar system [1], some basic concepts of Euclidean geometry: the half length and the midpoint of a segment, the perpendicular bisector of a segment, the medians (the cevians that join the vertices of a triangle to the midpoints of the opposite sides) of a triangle.
Partitioning Pythagorean Triangles Using Pythagorean Angles
Swenson, Carl E.; Yandl, Andre L.
2012-01-01
Inside any Pythagorean right triangle, it is possible to find a point M so that drawing segments from M to each vertex of the triangle yields angles whose sines and cosines are all rational. This article describes an algorithm that generates an infinite number of such points.
Circumcenter, Circumcircle and Centroid of a Triangle
Directory of Open Access Journals (Sweden)
Coghetto Roland
2016-03-01
Full Text Available We introduce, using the Mizar system [1], some basic concepts of Euclidean geometry: the half length and the midpoint of a segment, the perpendicular bisector of a segment, the medians (the cevians that join the vertices of a triangle to the midpoints of the opposite sides of a triangle.
The Fermat point for a taxicab triangle
Hanson, J. R.
2015-04-01
The Fermat point P for a triangle ABC is the point P the sum of whose distances from the vertices A, B and C is a minimum. This note will show how to find the Fermat point for any triangle using the taxicab metric.
Obtuse triangle suppression in anisotropic meshes
Sun, Feng; Choi, Yi King; Wang, Wen Ping; Yan, Dongming; Liu, Yang; Lé vy, Bruno L.
2011-01-01
Anisotropic triangle meshes are used for efficient approximation of surfaces and flow data in finite element analysis, and in these applications it is desirable to have as few obtuse triangles as possible to reduce the discretization error. We present a variational approach to suppressing obtuse triangles in anisotropic meshes. Specifically, we introduce a hexagonal Minkowski metric, which is sensitive to triangle orientation, to give a new formulation of the centroidal Voronoi tessellation (CVT) method. Furthermore, we prove several relevant properties of the CVT method with the newly introduced metric. Experiments show that our algorithm produces anisotropic meshes with much fewer obtuse triangles than using existing methods while maintaining mesh anisotropy. © 2011 Elsevier B.V. All rights reserved.
Obtuse triangle suppression in anisotropic meshes
Sun, Feng
2011-12-01
Anisotropic triangle meshes are used for efficient approximation of surfaces and flow data in finite element analysis, and in these applications it is desirable to have as few obtuse triangles as possible to reduce the discretization error. We present a variational approach to suppressing obtuse triangles in anisotropic meshes. Specifically, we introduce a hexagonal Minkowski metric, which is sensitive to triangle orientation, to give a new formulation of the centroidal Voronoi tessellation (CVT) method. Furthermore, we prove several relevant properties of the CVT method with the newly introduced metric. Experiments show that our algorithm produces anisotropic meshes with much fewer obtuse triangles than using existing methods while maintaining mesh anisotropy. © 2011 Elsevier B.V. All rights reserved.
Tight multilattices calculated by extended-cell cylindrization
Energy Technology Data Exchange (ETDEWEB)
Segev, M; Carmona, S
1983-01-01
Among the common features of advanced LWR concepts are the tightness of lattices and the symbiotic setting of different fuels. Such symbioses often come in the form of multilattices, whose numerically-repeated unit is a configuration of several pins, typically with one pin type at the center and pins of a second type surrounding the center pin. If this extended-cell (EC) unit is cylindricized, then a simple transport calculation of the unit will be possible. If the lattice of such units is tight, there is further an a priori reason to expect the cylindrization to introduce only a small distortion of the true neutron fluxes in the lattice. A strict numerical validation of the EC cylindrization approximation is impractical, but similar validations can be carried out for regular lattices, viewed as being made up of multicell units whose centers are moderators and whose peripheries are fuel pins. In these comparisons the EC cylindrization approximation gives good results.
Density conditions for triangles in multipartite graphs
DEFF Research Database (Denmark)
Bondy, Adrian; Shen, Jin; Thomassé, Stephan
2006-01-01
subgraphs in G. We investigate in particular the case where G is a complete multipartite graph. We prove that a finite tripartite graph with all edge densities greater than the golden ratio has a triangle and that this bound is best possible. Also we show that an infinite-partite graph with finite parts has...... a triangle, provided that the edge density between any two parts is greater than 1/2....
Evaluation of tight-pitch PWR cores
International Nuclear Information System (INIS)
Correa, F.; Driscoll, M.J.; Lanning, D.D.
1979-08-01
The impact of tight pinch cores on the consumption of natural uranium ore has been evaluated for two systems of coupled PWR's namely one particular type of thorium system - 235 U/UO 2 : Pu/ThO 2 : 233 U/ThO 2 - and the conventional recycle-mode uranium system - 235 U/UO 2 : Pu/UO 2 . The basic parameter varied was the fuel-to-moderator volume ratio (F/M) of the (uniform) lattice for the last core in each sequence. Although methods and data verification in the range of present interest, 0.5 (current lattices) 1.0, the EPRI-LEOPARD and LASER programs used for the thorium and uranium calculations, respectively, were successfully benchmarked against several of the more pertinent experiments
Graphene antidot lattice waveguides
DEFF Research Database (Denmark)
Pedersen, Jesper Goor; Gunst, Tue; Markussen, Troels
2012-01-01
We introduce graphene antidot lattice waveguides: nanostructured graphene where a region of pristine graphene is sandwiched between regions of graphene antidot lattices. The band gaps in the surrounding antidot lattices enable localized states to emerge in the central waveguide region. We model...... the waveguides via a position-dependent mass term in the Dirac approximation of graphene and arrive at analytical results for the dispersion relation and spinor eigenstates of the localized waveguide modes. To include atomistic details we also use a tight-binding model, which is in excellent agreement...... with the analytical results. The waveguides resemble graphene nanoribbons, but without the particular properties of ribbons that emerge due to the details of the edge. We show that electrons can be guided through kinks without additional resistance and that transport through the waveguides is robust against...
International Nuclear Information System (INIS)
Hasenfratz, P.
1983-01-01
The author presents a general introduction to lattice gauge theories and discusses non-perturbative methods in the gauge sector. He then shows how the lattice works in obtaining the string tension in SU(2). Lattice QCD at finite physical temperature is discussed. Universality tests in SU(2) lattice QCD are presented. SU(3) pure gauge theory is briefly dealt with. Finally, fermions on the lattice are considered. (Auth.)
Continuous Shearlet Tight Frames
Grohs, Philipp
2010-10-22
Based on the shearlet transform we present a general construction of continuous tight frames for L2(ℝ2) from any sufficiently smooth function with anisotropic moments. This includes for example compactly supported systems, piecewise polynomial systems, or both. From our earlier results in Grohs (Technical report, KAUST, 2009) it follows that these systems enjoy the same desirable approximation properties for directional data as the previous bandlimited and very specific constructions due to Kutyniok and Labate (Trans. Am. Math. Soc. 361:2719-2754, 2009). We also show that the representation formulas we derive are in a sense optimal for the shearlet transform. © 2010 Springer Science+Business Media, LLC.
The Asia-Pacific Strategic Triangle
DEFF Research Database (Denmark)
Schmidt, Johannes Dragsbæk
2014-01-01
The objective of this paper is to give insight into the debate over the strategic triangle and how it impacts conflict and security in South Asia. First the new geopolitical motives of the United States in the Asia-Pacific are outlined. Then the concept of strategic triangle is elaborated and its...... applicability discussed; third, details about China and India’s relations and responses to the new US policy are being analyzed; the perspective turns to the implications for conflict and security in South Asia with a focus on Afghanistan and Iran where oil and energy security are the main denominators...... of foreign policy calculations and moves in the strategic triangle; and finally, some concluding remarks are offered to explain the recent shifts in interactions between these core players in the emerging world order and whether a new geopolitical architecture is emerging...
LR: Compact connectivity representation for triangle meshes
Energy Technology Data Exchange (ETDEWEB)
Gurung, T; Luffel, M; Lindstrom, P; Rossignac, J
2011-01-28
We propose LR (Laced Ring) - a simple data structure for representing the connectivity of manifold triangle meshes. LR provides the option to store on average either 1.08 references per triangle or 26.2 bits per triangle. Its construction, from an input mesh that supports constant-time adjacency queries, has linear space and time complexity, and involves ordering most vertices along a nearly-Hamiltonian cycle. LR is best suited for applications that process meshes with fixed connectivity, as any changes to the connectivity require the data structure to be rebuilt. We provide an implementation of the set of standard random-access, constant-time operators for traversing a mesh, and show that LR often saves both space and traversal time over competing representations.
Topological magnon bands in ferromagnetic star lattice
International Nuclear Information System (INIS)
Owerre, S A
2017-01-01
The experimental observation of topological magnon bands and thermal Hall effect in a kagomé lattice ferromagnet Cu(1–3, bdc) has inspired the search for topological magnon effects in various insulating ferromagnets that lack an inversion center allowing a Dzyaloshinskii–Moriya (DM) spin–orbit interaction. The star lattice (also known as the decorated honeycomb lattice) ferromagnet is an ideal candidate for this purpose because it is a variant of the kagomé lattice with additional links that connect the up-pointing and down-pointing triangles. This gives rise to twice the unit cell of the kagomé lattice, and hence more interesting topological magnon effects. In particular, the triangular bridges on the star lattice can be coupled either ferromagnetically or antiferromagnetically which is not possible on the kagomé lattice ferromagnets. Here, we study DM-induced topological magnon bands, chiral edge modes, and thermal magnon Hall effect on the star lattice ferromagnet in different parameter regimes. The star lattice can also be visualized as the parent material from which topological magnon bands can be realized for the kagomé and honeycomb lattices in some limiting cases. (paper)
Topological magnon bands in ferromagnetic star lattice.
Owerre, S A
2017-05-10
The experimental observation of topological magnon bands and thermal Hall effect in a kagomé lattice ferromagnet Cu(1-3, bdc) has inspired the search for topological magnon effects in various insulating ferromagnets that lack an inversion center allowing a Dzyaloshinskii-Moriya (DM) spin-orbit interaction. The star lattice (also known as the decorated honeycomb lattice) ferromagnet is an ideal candidate for this purpose because it is a variant of the kagomé lattice with additional links that connect the up-pointing and down-pointing triangles. This gives rise to twice the unit cell of the kagomé lattice, and hence more interesting topological magnon effects. In particular, the triangular bridges on the star lattice can be coupled either ferromagnetically or antiferromagnetically which is not possible on the kagomé lattice ferromagnets. Here, we study DM-induced topological magnon bands, chiral edge modes, and thermal magnon Hall effect on the star lattice ferromagnet in different parameter regimes. The star lattice can also be visualized as the parent material from which topological magnon bands can be realized for the kagomé and honeycomb lattices in some limiting cases.
On dispersive derivation of triangle anomaly
International Nuclear Information System (INIS)
Horejsi, J.
1985-01-01
A straightforward generalization of the results of some previous treatments, in which the Adler-Bell-Jachiw triangle anomaly has been recovered with the help of dispersion relation is presented. The absorptive part of the VVA triangle diagram with the external momenta k, p at vector vertices such as K 2 =p 2 =0 is considered. An integral of the imaginary part of the relevant invariant amplitude is calculated explicitly. It is shown that the anomalous contribution to the axial Ward identity is reproduced. This also enables one to demonstrate the delta-like behaviour of sich an imaginary part in k 2 → 0, m → 0 limit
Less-Tight versus Tight Control of Hypertension in Pregnancy
Magee, Laura A.; von Dadelszen, Peter; Rey, Evelyne; Ross, Susan; Asztalos, Elizabeth; Murphy, Kellie E.; Menzies, Jennifer; Sanchez, Johanna; Singer, Joel; Gafni, Amiram; Gruslin, Andrée; Helewa, Michael; Hutton, Eileen; Lee, Shoo K.; Lee, Terry; Logan, Alexander G.; Ganzevoort, Wessel; Welch, Ross; Thornton, Jim G.; Moutquin, Jean-Marie
2015-01-01
BACKGROUND The effects of less-tight versus tight control of hypertension on pregnancy complications are unclear. METHODS We performed an open, international, multicenter trial involving women at 14 weeks 0 days to 33 weeks 6 days of gestation who had nonproteinuric preexisting or gestational
Building Intuitive Arguments for the Triangle Congruence Conditions
Piatek-Jimenez, Katrina
2008-01-01
The triangle congruence conditions are a central focus to nearly any course in Euclidean geometry. The author presents a hands-on activity that uses straws and pipe cleaners to explore and justify the triangle congruence conditions. (Contains 4 figures.)
Scaling Ratios and Triangles in Siegel Disks
DEFF Research Database (Denmark)
Buff, Xavier; Henriksen, Christian
1999-01-01
Let f(z)=e^{2i\\pi \\theta} + z^2, where \\theta is a quadratic irrational. McMullen proved that the Siegel disk for f is self-similar about the critical point, and we show that if \\theta = (\\sqrt{5}-1)/2 is the golden mean, then there exists a triangle contained in the Siegel disk, and with one...
Transfinite C2 interpolant over triangles
International Nuclear Information System (INIS)
Alfeld, P.; Barnhill, R.E.
1984-01-01
A transfinite C 2 interpolant on a general triangle is created. The required data are essentially C 2 , no compatibility conditions arise, and the precision set includes all polynomials of degree less than or equal to eight. The symbol manipulation language REDUCE is used to derive the scheme. The scheme is discretized to two different finite dimensional C 2 interpolants in an appendix
New Forms of Matter in Optical Lattices
2016-05-19
12211 Research Triangle Park, NC 27709-2211 optical lattice, quantum simulator, many body physics REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S...Reviewed Conference Proceeding publications (other than abstracts): Books Number of Manuscripts: 165.00Number of Presentations: Non Peer-Reviewed...Conference Proceeding publications (other than abstracts): (d) Manuscripts Received Paper TOTAL: Received Paper TOTAL: Received Paper TOTAL: Received Book
Tight junctions and human diseases.
Sawada, Norimasa; Murata, Masaki; Kikuchi, Keisuke; Osanai, Makoto; Tobioka, Hirotoshi; Kojima, Takashi; Chiba, Hideki
2003-09-01
Tight junctions are intercellular junctions adjacent to the apical end of the lateral membrane surface. They have two functions, the barrier (or gate) function and the fence function. The barrier function of tight junctions regulates the passage of ions, water, and various macromolecules, even of cancer cells, through paracellular spaces. The barrier function is thus relevant to edema, jaundice, diarrhea, and blood-borne metastasis. On the other hand, the fence function maintains cell polarity. In other words, tight junctions work as a fence to prevent intermixing of molecules in the apical membrane with those in the lateral membrane. This function is deeply involved in cancer cell biology, in terms of loss of cell polarity. Of the proteins comprising tight junctions, integral membrane proteins occludin, claudins, and JAMs have been recently discovered. Of these molecules, claudins are exclusively responsible for the formation of tight-junction strands and are connected with the actin cytoskeleton mediated by ZO-1. Thus, both functions of tight junctions are dependent on the integrity of the actin cytoskeleton as well as ATP. Mutations in the claudin14 and the claudin16 genes result in hereditary deafness and hereditary hypomagnesemia, respectively. Some pathogenic bacteria and viruses target and affect the tight-junction function, leading to diseases. In this review, the relationship between tight junctions and human diseases is summarized.
Tight closure and vanishing theorems
International Nuclear Information System (INIS)
Smith, K.E.
2001-01-01
Tight closure has become a thriving branch of commutative algebra since it was first introduced by Mel Hochster and Craig Huneke in 1986. Over the past few years, it has become increasingly clear that tight closure has deep connections with complex algebraic geometry as well, especially with those areas of algebraic geometry where vanishing theorems play a starring role. The purpose of these lectures is to introduce tight closure and to explain some of these connections with algebraic geometry. Tight closure is basically a technique for harnessing the power of the Frobenius map. The use of the Frobenius map to prove theorems about complex algebraic varieties is a familiar technique in algebraic geometry, so it should perhaps come as no surprise that tight closure is applicable to algebraic geometry. On the other hand, it seems that so far we are only seeing the tip of a large and very beautiful iceberg in terms of tight closure's interpretation and applications to algebraic geometry. Interestingly, although tight closure is a 'characteristic p' tool, many of the problems where tight closure has proved useful have also yielded to analytic (L2) techniques. Despite some striking parallels, there had been no specific result directly linking tight closure and L∼ techniques. Recently, however, the equivalence of an ideal central to the theory of tight closure was shown to be equivalent to a certain 'multiplier ideal' first defined using L2 methods. Presumably, deeper connections will continue to emerge. There are two main types of problems for which tight closure has been helpful: in identifying nice structure and in establishing uniform behavior. The original algebraic applications of tight closure include, for example, a quick proof of the Hochster-Roberts theorem on the Cohen-Macaulayness of rings of invariants, and also a refined version of the Brianqon-Skoda theorem on the uniform behaviour of integral closures of powers of ideals. More recent, geometric
Less-tight versus tight control of hypertension in pregnancy.
Magee, Laura A; von Dadelszen, Peter; Rey, Evelyne; Ross, Susan; Asztalos, Elizabeth; Murphy, Kellie E; Menzies, Jennifer; Sanchez, Johanna; Singer, Joel; Gafni, Amiram; Gruslin, Andrée; Helewa, Michael; Hutton, Eileen; Lee, Shoo K; Lee, Terry; Logan, Alexander G; Ganzevoort, Wessel; Welch, Ross; Thornton, Jim G; Moutquin, Jean-Marie
2015-01-29
The effects of less-tight versus tight control of hypertension on pregnancy complications are unclear. We performed an open, international, multicenter trial involving women at 14 weeks 0 days to 33 weeks 6 days of gestation who had nonproteinuric preexisting or gestational hypertension, office diastolic blood pressure of 90 to 105 mm Hg (or 85 to 105 mm Hg if the woman was taking antihypertensive medications), and a live fetus. Women were randomly assigned to less-tight control (target diastolic blood pressure, 100 mm Hg) or tight control (target diastolic blood pressure, 85 mm Hg). The composite primary outcome was pregnancy loss or high-level neonatal care for more than 48 hours during the first 28 postnatal days. The secondary outcome was serious maternal complications occurring up to 6 weeks post partum or until hospital discharge, whichever was later. Included in the analysis were 987 women; 74.6% had preexisting hypertension. The primary-outcome rates were similar among 493 women assigned to less-tight control and 488 women assigned to tight control (31.4% and 30.7%, respectively; adjusted odds ratio, 1.02; 95% confidence interval [CI], 0.77 to 1.35), as were the rates of serious maternal complications (3.7% and 2.0%, respectively; adjusted odds ratio, 1.74; 95% CI, 0.79 to 3.84), despite a mean diastolic blood pressure that was higher in the less-tight-control group by 4.6 mm Hg (95% CI, 3.7 to 5.4). Severe hypertension (≥160/110 mm Hg) developed in 40.6% of the women in the less-tight-control group and 27.5% of the women in the tight-control group (Phypertension. (Funded by the Canadian Institutes of Health Research; CHIPS Current Controlled Trials number, ISRCTN71416914; ClinicalTrials.gov number, NCT01192412.).
International Nuclear Information System (INIS)
Chadderton, L.T.; Johnson, E.; Wohlenberg, T.
1976-01-01
Void lattices in metals apparently owe their stability to elastically anisotropic interactions. An ordered array of voids on the anion sublattice in fluorite does not fit so neatly into this scheme of things. Crowdions may play a part in the formation of the void lattice, and stability may derive from other sources. (Auth.)
Empirical tight-binding parameters for solid C60
International Nuclear Information System (INIS)
Tit, N.; Kumar, V.
1993-01-01
We present a tight-binding model for the electronic structure of C 60 using four (1s and 3p) orbitals per carbon atom. The model has been developed by fitting the tight-binding parameters to the ab-initio pseudopotential calculation of Troullier and Martins (Phys. Rev. B46, 1754 (1992)) in the face-centered cubic (Fm3-bar) phase. Following this, calculations of the energy bands and the density of electronic states have been carried out as a function of the lattice constant. Good agreement has been obtained with the observed lattice-constant dependence of T c using McMillan's formula. Furthermore, calculations of the electronic structure are presented in the simple cubic (Pa3-bar) phase. (author). 43 refs, 3 figs, 1 tab
International Nuclear Information System (INIS)
Randjbar-Daemi, S.
1995-12-01
The so-called doubling problem in the lattice description of fermions led to a proof that under certain circumstances chiral gauge theories cannot be defined on the lattice. This is called the no-go theorem. It implies that if Γ/sub/A is defined on a lattice then its infrared limit, which should correspond to the quantum description of the classical action for the slowly varying fields on lattice scale, is inevitably a vector like theory. In particular, if not circumvented, the no-go theorem implies that there is no lattice formulation of the Standard Weinberg-Salam theory or SU(5) GUT, even though the fermions belong to anomaly-free representations of the gauge group. This talk aims to explain one possible attempt at bypassing the no-go theorem. 20 refs
Energy Technology Data Exchange (ETDEWEB)
Randjbar-Daemi, S
1995-12-01
The so-called doubling problem in the lattice description of fermions led to a proof that under certain circumstances chiral gauge theories cannot be defined on the lattice. This is called the no-go theorem. It implies that if {Gamma}/sub/A is defined on a lattice then its infrared limit, which should correspond to the quantum description of the classical action for the slowly varying fields on lattice scale, is inevitably a vector like theory. In particular, if not circumvented, the no-go theorem implies that there is no lattice formulation of the Standard Weinberg-Salam theory or SU(5) GUT, even though the fermions belong to anomaly-free representations of the gauge group. This talk aims to explain one possible attempt at bypassing the no-go theorem. 20 refs.
A survey of numerical cubature over triangles
Energy Technology Data Exchange (ETDEWEB)
Lyness, J.N.; Cools, R.
1993-12-31
This survey collects together theoretical results in the area of numerical cubature over triangles and is a vehicle for a current bibliography. We treat first the theory relating to regular integrands and then the corresponding theory for singular integrands with emphasis on the ``full comer singularity.`` Within these two sections we treat successively approaches based on transforming the triangle into a square, formulas based on polynomial moment fitting, and extrapolation techniques. Within each category we quote key theoretical results without proof, and relate other results and references to these. Nearly all the references we have found may be readily placed in one of these categories. This survey is theoretical in character and does not include recent work in adaptive and automatic integration.
Classical square-plus-triangle well fluid
International Nuclear Information System (INIS)
Boghdadi, M.
1984-01-01
A simplified model for the intermolecular-potential function which consists of a hard core and a square-plus-triangle well is proposed. The square width is taken to be lambda 1 -1 and the triangle width is lambda 2 -lambda 1 , where the diameter of the molecules is assumed to be epsilon. Under the restriction that the area under the potential well should be equal to 0.5epsilon, which has its own reason, it is shown that the appropriate choice of lambda 1 and lambda 2 that best mimics the Lennard-Jones (LJ) cut-off results is 1.15 and 1.85 respectively. With this choice for lambda 1 and lambda 2 , the proposed model is effective and satisfactory
"The Dreaded Black Triangle" - Orthodontics : The Choice
Directory of Open Access Journals (Sweden)
P Janardhanam
2010-01-01
The black triangle that resulted due to orthodontic treatment in a 15 year old female patient had been alleviated by using both orthodontic and periodontic means. This report explains the various treatment modalities that can be adopted to avoid embarrassing post-treatment results. Several methods of managing patients with gingival diastemas exist, but the interdisciplinary aspects of treatment must be emphasized to achieve best results. The orthodontist can play a significant role in helping to manage these cases.
State of the Coral Triangle: Malaysia
Asian Development Bank (ADB)
2014-01-01
Malaysia has made a firm commitment to sustainable management and conservation of its coastal and marine resources, helping formulate and implement the Sulu–Sulawesi Marine Ecoregion Initiative and the Coral Triangle Initiative. Rapid economic growth, uncontrolled tourism development, unregulated fishing, and unsustainable use of marine resources have depleted the country’s fish stocks, lost nearly 36% of its mangrove forests, and increased the number of endangered species. Despite impressive...
Workshop on the CKM Unitarity Triangle
Patrice Loïez
2002-01-01
The CKM Unitarity Triangle Workshop is meant to provide an opportunity for an intense and fruitful exchange of ideas between experimentalists and theorists to assess the present knowledge on fundamental parameters from the data of LEP and other colliders, to define an agenda of future measurements to further probe the model assumptions employed in the interpretation of the data and to indicate paths for the B physics programme at LHC.
International Nuclear Information System (INIS)
Thorn, C.B.
1988-01-01
The possibility of studying non-perturbative effects in string theory using a world sheet lattice is discussed. The light-cone lattice string model of Giles and Thorn is studied numerically to assess the accuracy of ''coarse lattice'' approximations. For free strings a 5 by 15 lattice seems sufficient to obtain better than 10% accuracy for the bosonic string tachyon mass squared. In addition a crude lattice model simulating string like interactions is studied to find out how easily a coarse lattice calculation can pick out effects such as bound states which would qualitatively alter the spectrum of the free theory. The role of the critical dimension in obtaining a finite continuum limit is discussed. Instead of the ''gaussian'' lattice model one could use one of the vertex models, whose continuum limit is the same as a gaussian model on a torus of any radius. Indeed, any critical 2 dimensional statistical system will have a stringy continuum limit in the absence of string interactions. 8 refs., 1 fig. , 9 tabs
International Nuclear Information System (INIS)
Smith, L.
1975-01-01
An analysis is given of a number of variants of the basic lattice of the planned ISABELLE storage rings. The variants were formed by removing cells from the normal part of the lattice and juggling the lengths of magnets, cells, and insertions in order to maintain a rational relation of circumference to that of the AGS and approximately the same dispersion. Special insertions, correction windings, and the working line with nonlinear resonances are discussed
Electromagnetic resonance in the asymmetric terahertz metamaterials with triangle microstructure
Xing, Yuanyuan; Zhang, Xiaoyu; Zhang, Qiang; Gu, Yanping; Qian, Yunan; Lin, Xingyue; Tang, Yunhai; Cheng, Xinli; Qin, Changfa; Shen, Jiaoyan; Zang, Taocheng; Ma, Chunlan
2018-05-01
We investigate terahertz transmission properties and electromagnetic resonance modes in the asymmetric triangle structures with the change of asymmetric distance and the direction of electric field. When the THz electric field is perpendicular to the split gap of triangle, the electric field can better excite the THz absorption in the triangle structures. Importantly, electromagnetically induced transparency (EIT) characteristics are observed in the triangle structures due to the destructive interference of the different excited modes. The distributions of electric field and surface current density simulated by finite difference time domain indicate that the bright mode is excited by the side of triangle structures and dark mode is excited by the gap-side of triangle. The present study is helpful to understand the electromagnetic resonance in the asymmetric triangular metamaterials.
Polarized targets at triangle universities nuclear laboratory
Energy Technology Data Exchange (ETDEWEB)
Seely, M.L. [North Carolina State Univ., Raleigh, NC (United States); Gould, C.R. [North Carolina State Univ., Raleigh, NC (United States); Haase, D.G. [North Carolina State Univ., Raleigh, NC (United States); Huffman, P.R. [Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Keith, C.D. [North Carolina State Univ., Raleigh, NC (United States); Roberson, N.R. [Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Tornow, W. [Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Wilburn, W.S. [Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States)
1995-03-01
A summary of the polarized and aligned nuclear targets which have been constructed and used at the Triangle Universities Nuclear Laboratory is given. Statically polarized targets, typically operating at a temperature of 12 mK and a magnetic field of 7 T, have provided significant nuclear polarization in {sup 1}H, {sup 3}He, {sup 27}Al, {sup 93}Nb and {sup 165}Ho. A rotating, aligned {sup 165}Ho target is also in use. A {sup 3}He melting curve thermometer has been developed for use in statically polarized targets. A dynamically polarized proton target is under construction. ((orig.))
Are tight gas resources overstated?
Energy Technology Data Exchange (ETDEWEB)
Roche, P.
2004-11-01
According to conventional wisdom, North America's tight gas resources are continuous, regional accumulations of water-free methane, trapped in low-permeability rock, and involving very little exploration risk. Backing up conventional wisdom, EnCana Corporation is investing heavily in technology-intensive and capital-intensive tight gas plays in Western Canada and the Rocky Mountain regions of the United States. On the other hand, a recent study in the Greater Green River Basin of southwestern Wyoming says that tight gas resources have been significantly overestimated, by as much as three to five times too high, and the risks of exploration are every bit as high as those for conventional exploration. This study essentially dismisses the whole idea of tight gas, or basin-centred gas as a myth, the authors being firmly convinced that tight gas formations should be viewed as conventional hydrocarbon systems, with the usual risks of exploration. This paper discusses the controversy created by this recent study and the implications for natural gas reserves on a basin and individual company level, and the risks associated with exploration. The views of EnCana Corporation, being the company most heavily involved in tight gas and coalbed methane, and those of John Masters, co-founder of Canadian Hunter Exploration Ltd., and discoverer of the blockbuster Elsmworth tight gas deposit in northeastern Alberta in the mid-1970s, are explained in considerable detail, in an effort to dismiss the doubters. EnCana officials and Masters argue that the points raised by the authors of the Greater Green River study do not hold water: Tight gas or basin gas is a distinct hydrocarbon formation, characterized by low permeability, therefore it is to be expected that the gas will take longer to come out of the ground. Neither is the role of water in basin-centred gas systems the major problem as claimed by the doubters. They also characterize it as imprudent to claim to know what the
International Nuclear Information System (INIS)
Catterall, Simon
2013-01-01
Discretization of supersymmetric theories is an old problem in lattice field theory. It has resisted solution until quite recently when new ideas drawn from orbifold constructions and topological field theory have been brought to bear on the question. The result has been the creation of a new class of lattice gauge theory in which the lattice action is invariant under one or more supersymmetries. The resultant theories are local and free of doublers and in the case of Yang-Mills theories also possess exact gauge invariance. In principle they form the basis for a truly non-perturbative definition of the continuum supersymmetric field theory. In this talk these ideas are reviewed with particular emphasis being placed on N = 4 super Yang-Mills theory.
International Nuclear Information System (INIS)
Creutz, M.
1984-01-01
After reviewing some recent developments in supercomputer access, the author discusses a few areas where perturbation theory and lattice gauge simulations make contact. The author concludes with a brief discussion of a deterministic dynamics for the Ising model. This may be useful for numerical studies of nonequilibrium phenomena. 13 references
Star-Triangle Relation of the Chiral Potts Model Revisited
Horibe, M.; Shigemoto, K.
2001-01-01
We give the simple proof of the star-triangle relation of the chiral Potts model. We also give the constructive way to understand the star-triangle relation of the chiral Potts model, which may give the hint to give the new integrable models.
Triangle-free graphs whose independence number equals the degree
DEFF Research Database (Denmark)
Brandt, Stephan
2010-01-01
In a triangle-free graph, the neighbourhood of every vertex is an independent set. We investigate the class S of triangle-free graphs where the neighbourhoods of vertices are maximum independent sets. Such a graph G must be regular of degree d = α (G) and the fractional chromatic number must sati...
Uses of systemic approach and chemist's triangle in teaching and ...
African Journals Online (AJOL)
This paper describes uses of the systemic chemistry triangle [SCT] in which we get the benefits of both systemic approach and chemist's triangle in teaching and learning chemistry. SCT creates active learning environment enable students to gain high mental and professional skills, correct cognition, positive attitudes ...
The DNA Triangle and Its Application to Learning Meiosis
Wright, L. Kate; Catavero, Christina M.; Newman, Dina L.
2017-01-01
Although instruction on meiosis is repeated many times during the undergraduate curriculum, many students show poor comprehension even as upper-level biology majors. We propose that the difficulty lies in the complexity of understanding DNA, which we explain through a new model, the DNA triangle. The "DNA triangle" integrates three…
Some Unusual Expressions for the Inradius of a Triangle
Osler, Thomas J.; Chandrupatla, Tirupathi R.
2005-01-01
Several formulae for the inradius of various types of triangles are derived. Properties of the inradius and trigonometric functions of the angles of Pythagorean and Heronian triangles are also presented. The entire presentation is elementary and suitable for classes in geometry, precalculus mathematics and number theory.
Angle bisectors of a triangle in $I_2$
Kolar-Begović, Zdenka; Kolar_Šuper, Ružica; Volenec, Vladimir
2008-01-01
The concept of an angle bisector of the triangle will be introduced in an isotropic plane. Some statements about relationships between the introduced concepts and some other previously studied geometric concepts about triangles will be investigated in an isotropic plane. A number of these statements seems to be new, and some of them are known in Euclidean geometry.
Relations between Some Characteristic Lengths in a Triangle
Koepf, Wolfram; Brede, Markus
2005-01-01
The paper's aim is to note a remarkable (and apparently unknown) relation for right triangles, its generalisation to arbitrary triangles and the possibility to derive these and some related relations by elimination using Groebner basis computations with a modern computer algebra system. (Contains 9 figures.)
Pascal-Like Triangle and Pascal-Like Functional Matrix
Directory of Open Access Journals (Sweden)
M. Bayat
2013-06-01
Full Text Available . In this paper we shall first introduce the Pascal-like triangle, using a generalization of the recurrence relation for arrays of Pascal triangle. Then we define the Pascal-like functional and Fermat-like matrices and investigate their algebraic properties. Finally, we obtain some binomial identities, using these matrices
Energy Technology Data Exchange (ETDEWEB)
M. Battaglia et al.
2004-04-02
This report contains the results of the Workshop on the CKM Unitarity Triangle that was held at CERN on 13-16 February 2002. There had been several Workshops on B physics that concentrated on studies at e{sup +}e{sup -} machines, at the Tevatron, or at LHC separately. Here we brought together experts of different fields, both theorists and experimentalists, to study the determination of the CKM matrix from all the available data of K, D, and B physics. The analysis of LEP data for B physics is reaching its end, and one of the goals of the Workshop was to underline the results that have been achieved at LEP, SLC, and CESR. Another goal was to prepare for the transfer of responsibility for averaging B physics properties, that has developed within the LEP community, to the present main actors of these studies, from the B factory and the Tevatron experiments. The optimal way to combine the various experimental and theoretical inputs and to fit for the apex of the Unitarity Triangle has been a contentious issue. A further goal of the Workshop was to bring together the proponents of different fitting strategies, and to compare their approaches when applied to the same inputs. Since lattice QCD plays a very important role in the determination of the non-perturbative parameters needed to constrain the CKM unitarity triangle, the first Workshop was seen as an excellent opportunity to bring together lattice theorists with the aim of establishing a working group to compile averages for phenomenologically relevant quantities. Representatives from lattice collaborations around the world were invited to attend a meeting during the Workshop. A consensus was reached to set up three test working groups, collectively known as the ''CKM Lattice Working Group'', to review a number of well-studied quantities: quark masses, the kaon B-parameter, and the matrix elements relevant for neutral B-meson mixing. This report is organized as a coherent document with chapters
Update of the Unitarity Triangle Analysis
Bevan, A.J.; Ciuchini, M.; Derkach, D.; Stocchi, A.; Franco, E.; Silvestrini, L.; Lubicz, V.; Tarantino, Cecilia; Martinelli, G.; Parodi, F.; Schiavi, C.; Pierini, M.; Sordini, V.; Vagnoni, V.
2010-01-01
We present the status of the Unitarity Triangle Analysis (UTA), within the Standard Model (SM) and beyond, with experimental and theoretical inputs updated for the ICHEP 2010 conference. Within the SM, we find that the general consistency among all the constraints leaves space only to some tension (between the UTA prediction and the experimental measurement) in BR(B -> tau nu), sin(2 beta) and epsilon_K. In the UTA beyond the SM, we allow for New Physics (NP) effects in (Delta F)=2 processes. The hint of NP at the 2.9 sigma level in the B_s-\\bar B_s mixing turns out to be confirmed by the present update, which includes the new D0 result on the dimuon charge asymmetry but not the new CDF measurement of phi_s, being the likelihood not yet released.
Tightness of voter model interfaces
Czech Academy of Sciences Publication Activity Database
Sturm, A.; Swart, Jan M.
2008-01-01
Roč. 13, - (2008), s. 165-174 ISSN 1083-589X R&D Projects: GA ČR GA201/06/1323; GA ČR GA201/07/0237 Institutional research plan: CEZ:AV0Z10750506 Keywords : long range voter model * swapping voter model * interface tightness * exclusion process Subject RIV: BD - Theory of Information Impact factor: 0.392, year: 2008 http://www.emis.de/journals/EJP-ECP/_ejpecp/index.html
Local thermal-hydraulic behaviour in tight 7-rod bundles
International Nuclear Information System (INIS)
Cheng, X.; Yu, Y.Q.
2009-01-01
Advanced water-cooled reactor concepts with tight lattices have been proposed worldwide to improve the fuel utilization and the economic competitiveness. In the present work, experimental investigations were performed on thermal-hydraulic behaviour in tight hexagonal 7-rod bundles under both single-phase and two-phase conditions. Freon-12 was used as working fluid due to its convenient operating parameters. Tests were carried out under both single-phase and two-phase flow conditions. Rod surface temperatures are measured at a fixed axial elevation and in various circumferential positions. Test data with different radial power distributions are analyzed. Measured surface temperatures of unheated rods are used for the assessment of and comparison with numerical codes. In addition, numerical simulation using sub-channel analysis code MATRA and the computational fluid dynamics (CFD) code ANSYS-10 is carried out to understand the experimental data and to assess the validity of these codes in the prediction of flow and heat transfer behaviour in tight rod bundle geometries. Numerical results are compared with experimental data. A good agreement between the measured temperatures on the unheated rod surface and the CFD calculation is obtained. Both sub-channel analysis and CFD calculation indicates that the turbulent mixing in the tight rod bundle is significantly stronger than that computed with a well established correlation.
Tight or sick building syndrome
Energy Technology Data Exchange (ETDEWEB)
Thirumalaikolundusubramanian, P; Shanmuganadan, S [Madurai Kamaraj Univ. (India). Dept. of Geography; Uma, A [Madurai Medical Coll. (India). Dept. of Medicine and Microbiology
1991-01-01
Modern buildings are designed with the usual heating, air-conditioning and ventilation equipment. In most of these buildings, air is continuously recirculated and, as a result, workers suffer from tight or sick building syndrome. This syndrome is discussed with reference to symptoms of air contamination, ventilation system standards and research needs. The most common symptoms of tight building syndrome are eye, nose and throat irritation, headache, fatigue, sneezing, difficulty in wearing contact lenses, chest tightness, nausea, dizziness and dermatitis. Symptoms experienced by 50 doctors and 50 paramedical personnel working in an air-conditioned intensive care unit and operating theatres of the Government Rajaji Hospital, Madurai in India were studied by means of a questionnaire survey. In the present study, respiratory and ocular symptoms were observed more in those working in operating theatres and were believed to be due to excessive use of formaldehyde used for sterilization. Various suggestions were made to prevent sick building syndrome. Moreover, the physicians treating sick individuals should be aware of the symptoms caused by indoor air pollutants as sufferers invariably require a change of environment rather than drugs. (orig.).
Economic Analysis of Asian Growth Triangles : The Johor-Singapore-Riau Growth Triangle
Koch, Glenn G.
2000-01-01
In looking at the Asian economy, particularly the Growth Triangle which includes Singapore, Malaysia and Indonesia, one can infer a great deal. With the Asian monetary crisis affecting the world, and certainly the Asian region in particular, some economists believe it is a mistake to evaluate such matters based on tradition. Rather, a school of thought dubbed the New Institutional Economics has come into being and while not everyone considers it to be a truly new approach, the bottom line is ...
Tight-Binding Parametrization for Photonic Band Gap Materials
International Nuclear Information System (INIS)
Lidorikis, E.; Sigalas, M.M.; Soukoulis, C.M.; Economou, E.N.; Soukoulis, C.M.
1998-01-01
The idea of the linear combination of atomic orbitals method, well known from the study of electrons, is extended to the classical wave case. The Mie resonances of the isolated scatterer in the classical wave case are analogous to the atomic orbitals in the electronic case. The matrix elements of the two-dimensional tight-binding (TB) Hamiltonian are obtained by fitting to ab initio results. The transferability of the TB model is tested by reproducing accurately the band structure of different 2D lattices, with and without defects, and at two different dielectric contrasts. copyright 1998 The American Physical Society
Grouper: a compact, streamable triangle mesh data structure.
Luffel, Mark; Gurung, Topraj; Lindstrom, Peter; Rossignac, Jarek
2014-01-01
We present Grouper: an all-in-one compact file format, random-access data structure, and streamable representation for large triangle meshes. Similarly to the recently published SQuad representation, Grouper represents the geometry and connectivity of a mesh by grouping vertices and triangles into fixed-size records, most of which store two adjacent triangles and a shared vertex. Unlike SQuad, however, Grouper interleaves geometry with connectivity and uses a new connectivity representation to ensure that vertices and triangles can be stored in a coherent order that enables memory-efficient sequential stream processing. We present a linear-time construction algorithm that allows streaming out Grouper meshes using a small memory footprint while preserving the initial ordering of vertices. As a part of this construction, we show how the problem of assigning vertices and triangles to groups reduces to a well-known NP-hard optimization problem, and present a simple yet effective heuristic solution that performs well in practice. Our array-based Grouper representation also doubles as a triangle mesh data structure that allows direct access to vertices and triangles. Storing only about two integer references per triangle--i.e., less than the three vertex references stored with each triangle in a conventional indexed mesh format--Grouper answers both incidence and adjacency queries in amortized constant time. Our compact representation enables data-parallel processing on multicore computers, instant partitioning and fast transmission for distributed processing, as well as efficient out-of-core access. We demonstrate the versatility and performance benefits of Grouper using a suite of example meshes and processing kernels.
Grouper: A Compact, Streamable Triangle Mesh Data Structure
Energy Technology Data Exchange (ETDEWEB)
Luffel, Mark [Georgia Inst. of Technology, Atlanta, GA (United States). Visualization and Usability Center (GVU); Gurung, Topraj [Georgia Inst. of Technology, Atlanta, GA (United States). Visualization and Usability Center (GVU); Lindstrom, Peter [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rossignac, Jarek [Georgia Inst. of Technology, Atlanta, GA (United States). Visualization and Usability Center (GVU)
2014-01-01
Here, we present Grouper: an all-in-one compact file format, random-access data structure, and streamable representation for large triangle meshes. Similarly to the recently published SQuad representation, Grouper represents the geometry and connectivity of a mesh by grouping vertices and triangles into fixed-size records, most of which store two adjacent triangles and a shared vertex. Unlike SQuad, however, Grouper interleaves geometry with connectivity and uses a new connectivity representation to ensure that vertices and triangles can be stored in a coherent order that enables memory-efficient sequential stream processing. We also present a linear-time construction algorithm that allows streaming out Grouper meshes using a small memory footprint while preserving the initial ordering of vertices. In this construction, we show how the problem of assigning vertices and triangles to groups reduces to a well-known NP-hard optimization problem, and present a simple yet effective heuristic solution that performs well in practice. Our array-based Grouper representation also doubles as a triangle mesh data structure that allows direct access to vertices and triangles. Storing only about two integer references per triangle-i.e., less than the three vertex references stored with each triangle in a conventional indexed mesh format-Grouper answers both incidence and adjacency queries in amortized constant time. Our compact representation enables data-parallel processing on multicore computers, instant partitioning and fast transmission for distributed processing, as well as efficient out-of-core access. We demonstrate the versatility and performance benefits of Grouper using a suite of example meshes and processing kernels.
Energy Technology Data Exchange (ETDEWEB)
Schaefer, Stefan [DESY (Germany). Neumann Inst. for Computing
2016-11-01
These configurations are currently in use in many on-going projects carried out by researchers throughout Europe. In particular this data will serve as an essential input into the computation of the coupling constant of QCD, where some of the simulations are still on-going. But also projects computing the masses of hadrons and investigating their structure are underway as well as activities in the physics of heavy quarks. As this initial project of gauge field generation has been successful, it is worthwhile to extend the currently available ensembles with further points in parameter space. These will allow to further study and control systematic effects like the ones introduced by the finite volume, the non-physical quark masses and the finite lattice spacing. In particular certain compromises have still been made in the region where pion masses and lattice spacing are both small. This is because physical pion masses require larger lattices to keep the effects of the finite volume under control. At light pion masses, a precise control of the continuum extrapolation is therefore difficult, but certainly a main goal of future simulations. To reach this goal, algorithmic developments as well as faster hardware will be needed.
Sense and Sensibility:The Erotic Triangle in Shakespearean Sonnets
Institute of Scientific and Technical Information of China (English)
舒畅
2017-01-01
The male-female-male relationship is a recurrent theme in William Shakespeare's sonnets. In Eve Sedgwick's influen-tial queer study book Between Men:English Literature and Male Homosocial Desire, she first interpreted the relationship within the model of erotic triangle. On the basis of Sedgwick's theory, the triangle relationship in the Sonnets is analyzed—Shakespeare con-structs an erotic triangle where males by identifying, cooperating, and competing with each other, maintain their homosocial bond upon heterosexual but misogynous desires towards a female. The contradictory relationship reflects Shakespeare 's struggle vis-à-vis a Renaissance literary theme:rationality versus passion, with the former mounting over the latter.
Sense and Sensibility:The Erotic Triangle in Shakespearean Sonnets
Institute of Scientific and Technical Information of China (English)
舒畅
2017-01-01
The male-female-male relationship is a recurrent theme in William Shakespeare's sonnets. In Eve Sedgwick's influen-tial queer study book Between Men: English Literature and Male Homosocial Desire, she first interpreted the relationship within the model of erotic triangle. On the basis of Sedgwick's theory, the triangle relationship in the Sonnets is analyzed—Shakespeare con-structs an erotic triangle where males by identifying, cooperating, and competing with each other, maintain their homosocial bond upon heterosexual but misogynous desires towards a female. The contradictory relationship reflects Shakespeare's struggle vis-à-vis a Renaissance literary theme: rationality versus passion, with the former mounting over the latter.
Applied psychometrics in clinical psychiatry: the pharmacopsychometric triangle
DEFF Research Database (Denmark)
Bech, P; Bech, P
2009-01-01
OBJECTIVE: To consider applied psychometrics in psychiatry as a discipline focusing on pharmacopsychology rather than psychopharmacology as illustrated by the pharmacopsychometric triangle. METHOD: The pharmacopsychological dimensions of clinically valid effects of drugs (antianxiety, antidepress......OBJECTIVE: To consider applied psychometrics in psychiatry as a discipline focusing on pharmacopsychology rather than psychopharmacology as illustrated by the pharmacopsychometric triangle. METHOD: The pharmacopsychological dimensions of clinically valid effects of drugs (antianxiety...... psychometrics in psychiatry have been found to cover a pharmacopsychometric triangle illustrating the measurements of wanted and unwanted effects of pharmacotherapeutic drugs as well as health-related quality of life....
GLINT. Gravitational-wave laser INterferometry triangle
Aria, Shafa; Azevedo, Rui; Burow, Rick; Cahill, Fiachra; Ducheckova, Lada; Holroyd, Alexa; Huarcaya, Victor; Järvelä, Emilia; Koßagk, Martin; Moeckel, Chris; Rodriguez, Ana; Royer, Fabien; Sypniewski, Richard; Vittori, Edoardo; Yttergren, Madeleine
2017-11-01
When the universe was roughly one billion years old, supermassive black holes (103-106 solar masses) already existed. The occurrence of supermassive black holes on such short time scales are poorly understood in terms of their physical or evolutionary processes. Our current understanding is limited by the lack of observational data due the limits of electromagnetic radiation. Gravitational waves as predicted by the theory of general relativity have provided us with the means to probe deeper into the history of the universe. During the ESA Alpach Summer School of 2015, a group of science and engineering students devised GLINT (Gravitational-wave Laser INterferometry Triangle), a space mission concept capable of measuring gravitational waves emitted by black holes that have formed at the early periods after the big bang. Morespecifically at redshifts of 15 big bang) in the frequency range 0.01 - 1 Hz. GLINT design strain sensitivity of 5× 10^{-24} 1/√ { {Hz}} will theoretically allow the study of early black holes formations as well as merging events and collapses. The laser interferometry, the technology used for measuring gravitational waves, monitors the separation of test masses in free-fall, where a change of separation indicates the passage of a gravitational wave. The test masses will be shielded from disturbing forces in a constellation of three geocentric orbiting satellites.
Update of the Unitarity Triangle Analysis
International Nuclear Information System (INIS)
Tarantino, C.; Bona, M.; Sordini, V.
2009-01-01
We present the update of the Unitarity Triangle (UT) analysis within the Standard Model (SM) and beyond. Within the SM, combining the direct measurements on sides and angles, the UT turns out to be overconstraint in a consistent way, showing that the CKM matrix is the dominant source of flavour mixing and CP-violation and that New Physics (NP) effects can appear at most as small corrections to the CKM picture. Generalizing the UT analysis to investigate NP effects, constraints on b → s transitions are also included and both CKM and NP parameters are fitted simultaneously. While no evidence of NP effects is found in K - (bar) K and B d - (bar) B d mixing, in the B s - (bar) B s mixing an hint of NP is found. The UT analysis beyond the SM also allows us to derive bounds on the coefficients of the most general ΔF = 2 effective Hamiltonian, that can be translated into bounds on the NP scale. (authors)
Thermoelectric properties of finite graphene antidot lattices
DEFF Research Database (Denmark)
Gunst, Tue; Markussen, Troels; Jauho, Antti-Pekka
2011-01-01
We present calculations of the electronic and thermal transport properties of graphene antidot lattices with a finite length along the transport direction. The calculations are based on the π-tight-binding model and the Brenner potential. We show that both electronic and thermal transport...... properties converge fast toward the bulk limit with increasing length of the lattice: only a few repetitions (≃6) of the fundamental unit cell are required to recover the electronic band gap of the infinite lattice as a transport gap for the finite lattice. We investigate how different antidot shapes...... and sizes affect the thermoelectric properties. The resulting thermoelectric figure of merit, ZT, can exceed 0.25, and it is highly sensitive to the atomic arrangement of the antidot edges. Specifically, hexagonal holes with pure armchair edges lead to an order-of-magnitude larger ZT as compared to pure...
Vertex Normals and Face Curvatures of Triangle Meshes
Sun, Xiang; Jiang, Caigui; Wallner, Johannes; Pottmann, Helmut
2016-01-01
This study contributes to the discrete differential geometry of triangle meshes, in combination with discrete line congruences associated with such meshes. In particular we discuss when a congruence defined by linear interpolation of vertex normals
Band structures in Sierpinski triangle fractal porous phononic crystals
International Nuclear Information System (INIS)
Wang, Kai; Liu, Ying; Liang, Tianshu
2016-01-01
In this paper, the band structures in Sierpinski triangle fractal porous phononic crystals (FPPCs) are studied with the aim to clarify the effect of fractal hierarchy on the band structures. Firstly, one kind of FPPCs based on Sierpinski triangle routine is proposed. Then the influence of the porosity on the elastic wave dispersion in Sierpinski triangle FPPCs is investigated. The sensitivity of the band structures to the fractal hierarchy is discussed in detail. The results show that the increase of the hierarchy increases the sensitivity of ABG (Absolute band gap) central frequency to the porosity. But further increase of the fractal hierarchy weakens this sensitivity. On the same hierarchy, wider ABGs could be opened in Sierpinski equilateral triangle FPPC; whilst, a lower ABG could be opened at lower porosity in Sierpinski right-angled isosceles FPPCs. These results will provide a meaningful guidance in tuning band structures in porous phononic crystals by fractal design.
Exploring fraud triangle in understanding ethics pre-cautionary: a ...
African Journals Online (AJOL)
Exploring fraud triangle in understanding ethics pre-cautionary: a Malaysian ... Journal of Fundamental and Applied Sciences ... Various reports on the involvement of government officials in fraud cases indicate the lacking of ethical systems.
Metrical relationships in a standard triangle in an isotropic plane
Kolar-Šuper, R.; Kolar-Begović, Z.; Volenec, V.; Beban-Brkić, J.
2005-01-01
Each allowable triangle of an isotropic plane can be set in a standard position, in which it is possible to prove geometric properties analytically in a simplified and easier way by means of the algebraic theory developed in this paper.
A Heuristic Algorithm for Solving Triangle Packing Problem
Directory of Open Access Journals (Sweden)
Ruimin Wang
2013-01-01
Full Text Available The research on the triangle packing problem has important theoretic significance, which has broad application prospects in material processing, network resource optimization, and so forth. Generally speaking, the orientation of the triangle should be limited in advance, since the triangle packing problem is NP-hard and has continuous properties. For example, the polygon is not allowed to rotate; then, the approximate solution can be obtained by optimization method. This paper studies the triangle packing problem by a new kind of method. Such concepts as angle region, corner-occupying action, corner-occupying strategy, and edge-conjoining strategy are presented in this paper. In addition, an edge-conjoining and corner-occupying algorithm is designed, which is to obtain an approximate solution. It is demonstrated that the proposed algorithm is highly efficient, and by the time complexity analysis and the analogue experiment result is found.
Band structures in Sierpinski triangle fractal porous phononic crystals
Energy Technology Data Exchange (ETDEWEB)
Wang, Kai; Liu, Ying, E-mail: yliu5@bjtu.edu.cn; Liang, Tianshu
2016-10-01
In this paper, the band structures in Sierpinski triangle fractal porous phononic crystals (FPPCs) are studied with the aim to clarify the effect of fractal hierarchy on the band structures. Firstly, one kind of FPPCs based on Sierpinski triangle routine is proposed. Then the influence of the porosity on the elastic wave dispersion in Sierpinski triangle FPPCs is investigated. The sensitivity of the band structures to the fractal hierarchy is discussed in detail. The results show that the increase of the hierarchy increases the sensitivity of ABG (Absolute band gap) central frequency to the porosity. But further increase of the fractal hierarchy weakens this sensitivity. On the same hierarchy, wider ABGs could be opened in Sierpinski equilateral triangle FPPC; whilst, a lower ABG could be opened at lower porosity in Sierpinski right-angled isosceles FPPCs. These results will provide a meaningful guidance in tuning band structures in porous phononic crystals by fractal design.
The stable stiffness triangle - drained sand during deformation cycles
DEFF Research Database (Denmark)
Sabaliauskas, Tomas; Ibsen, Lars Bo
2017-01-01
Cyclic, drained sand stiffness was observed using the Danish triaxial appa- ratus. New, deformation dependant soil property (the stable stiffness triangle) was detected. Using the the stable stiffness triangle, secant stiffness of drained sand was plausible to predict (and control) even during ir...... findings can find application in off-shore, seismic and other engi- neering practice, or inspire new branches of research and modelling wherever dynamic, cyclic or transient loaded sand is encountered....
On degree sums of a triangle-free graph
DEFF Research Database (Denmark)
Brandt, Stephan; Harant, J.; Naumann, S.
2014-01-01
For a simple triangle-free k-chromatic graph G with k >= 2 the upper bound m(n-f (k-2)) on the sum Sigma(2)(G) = Sigma(x is an element of V(G))d(2)(x) of the squares of the degrees of G is proved, where n, m, and f(1) are the order of G, the size of G, and the minimum order of a triangle-free l-c...
Trigonometric solutions of triangle equations. Simple Lie superalgebras
International Nuclear Information System (INIS)
Bazhanov, V.V.; Shadrikov, A.G.
1988-01-01
Trigonometric solutions of the graded triangle equation are constructed for the fundamental representations of all simple (nonexceptional) Lie superalgebras with nondegenerate metric. In Sec. 1, we introduce the concept of Z 2 graded spaces and give the basic definitions. In Sec. 2, we determine fundamental representations of the Lie superalgebras sl(mn) and osp(2rs) and give explicit realizations of the Coxeter automorphisms. In secs. 3 and 4, we give the trigonometric solutions of the graded triangle equation (quantum R matrices)
Coloring triangle-free graphs with fixed size
DEFF Research Database (Denmark)
Thomassen, Carsten; Gimbel, John
2000-01-01
Combining recent results on colorings and Ramsey theory, we show that if G is a triangle-free graph with e edges then the chromatic number of G is at most cel(1/3)(log e)(-2/3) for some constant c. In a previous paper, we found an upper bound on the chromatic number of a triangle-free graph of ge...
Moving triangle singularities: the possibilities for observation in deuteron reactions
International Nuclear Information System (INIS)
Kolybasov, V.M.
1996-01-01
If the amplitude of direct reaction is dominated by the triangle graph then it can be identified observing the picture corresponding to so-called moving triangle singularity: the form of the distribution with respect to the invariant mass of several final particles must change with momentum transferred from initial fast particle to final one. The possibilities for observation are discussed using two reactions, namely deuteron break up and η-meson production pd → pdη [ru
Diagnosing the tight building syndrome
Energy Technology Data Exchange (ETDEWEB)
Rogers, S.A.
1987-12-01
Formaldehyde is but one of many chemicals capable of causing the tight building syndrome or environmentally induced illness (EI). The spectrum of symptoms it may induce includes attacks of headache, flushing, laryngitis, dizziness, nausea, extreme weakness, arthralgia, unwarranted depression, dysphonia, exhaustion, inability to think clearly, arrhythmia or muscle spasms. The nonspecificity of such symptoms can baffle physicians from many specialties. Presented herein is a simple office method for demonstrating that formaldehyde is among the etiologic agents triggering these symptoms. The very symptoms that patients complain of can be provoked within minutes, and subsequently abolished, with an intradermal injection of the appropriate strength of formaldehyde. This injection aids in convincing the patient of the cause of the symptoms so he can initiate measure to bring his disease under control.
Invasive tightly coupled processor arrays
LARI, VAHID
2016-01-01
This book introduces new massively parallel computer (MPSoC) architectures called invasive tightly coupled processor arrays. It proposes strategies, architecture designs, and programming interfaces for invasive TCPAs that allow invading and subsequently executing loop programs with strict requirements or guarantees of non-functional execution qualities such as performance, power consumption, and reliability. For the first time, such a configurable processor array architecture consisting of locally interconnected VLIW processing elements can be claimed by programs, either in full or in part, using the principle of invasive computing. Invasive TCPAs provide unprecedented energy efficiency for the parallel execution of nested loop programs by avoiding any global memory access such as GPUs and may even support loops with complex dependencies such as loop-carried dependencies that are not amenable to parallel execution on GPUs. For this purpose, the book proposes different invasion strategies for claiming a desire...
The star-triangle relation, lens partition function, and hypergeometric sum/integrals
Energy Technology Data Exchange (ETDEWEB)
Gahramanov, Ilmar [Max Planck Institute for Gravitational Physics (Albert Einstein Institute),Am Mühlenberg 1, D-14476 Potsdam (Germany); Institute of Radiation Problems ANAS,B. Vahabzade 9, AZ1143 Baku (Azerbaijan); Department of Mathematics, Khazar University,Mehseti St. 41, AZ1096 Baku (Azerbaijan); Kels, Andrew P. [Institute of Physics, University of Tokyo,Komaba, Tokyo 153-8902 (Japan)
2017-02-08
The aim of the present paper is to consider the hyperbolic limit of an elliptic hypergeometric sum/integral identity, and associated lattice model of statistical mechanics previously obtained by the second author. The hyperbolic sum/integral identity obtained from this limit, has two important physical applications in the context of the so-called gauge/YBE correspondence. For statistical mechanics, this identity is equivalent to a new solution of the star-triangle relation form of the Yang-Baxter equation, that directly generalises the Faddeev-Volkov models to the case of discrete and continuous spin variables. On the gauge theory side, this identity represents the duality of lens (S{sub b}{sup 3}/ℤ{sub r}) partition functions, for certain three-dimensional N=2 supersymmetric gauge theories.
The star-triangle relation, lens partition function, and hypergeometric sum/integrals
International Nuclear Information System (INIS)
Gahramanov, Ilmar; Kels, Andrew P.
2017-01-01
The aim of the present paper is to consider the hyperbolic limit of an elliptic hypergeometric sum/integral identity, and associated lattice model of statistical mechanics previously obtained by the second author. The hyperbolic sum/integral identity obtained from this limit, has two important physical applications in the context of the so-called gauge/YBE correspondence. For statistical mechanics, this identity is equivalent to a new solution of the star-triangle relation form of the Yang-Baxter equation, that directly generalises the Faddeev-Volkov models to the case of discrete and continuous spin variables. On the gauge theory side, this identity represents the duality of lens (S b 3 /ℤ r ) partition functions, for certain three-dimensional N=2 supersymmetric gauge theories.
LATTICE: an interactive lattice computer code
International Nuclear Information System (INIS)
Staples, J.
1976-10-01
LATTICE is a computer code which enables an interactive user to calculate the functions of a synchrotron lattice. This program satisfies the requirements at LBL for a simple interactive lattice program by borrowing ideas from both TRANSPORT and SYNCH. A fitting routine is included
Tightly Secure Signatures From Lossy Identification Schemes
Abdalla , Michel; Fouque , Pierre-Alain; Lyubashevsky , Vadim; Tibouchi , Mehdi
2015-01-01
International audience; In this paper, we present three digital signature schemes with tight security reductions in the random oracle model. Our first signature scheme is a particularly efficient version of the short exponent discrete log-based scheme of Girault et al. (J Cryptol 19(4):463–487, 2006). Our scheme has a tight reduction to the decisional short discrete logarithm problem, while still maintaining the non-tight reduction to the computational version of the problem upon which the or...
Effective field theory of interactions on the lattice
DEFF Research Database (Denmark)
Valiente, Manuel; Zinner, Nikolaj T.
2015-01-01
We consider renormalization of effective field theory interactions by discretizing the continuum on a tight-binding lattice. After studying the one-dimensional problem, we address s-wave collisions in three dimensions and relate the bare lattice coupling constants to the continuum coupling consta...... constants. Our method constitutes a very simple avenue for the systematic renormalization in effective field theory, and is especially useful as the number of interaction parameters increases.......We consider renormalization of effective field theory interactions by discretizing the continuum on a tight-binding lattice. After studying the one-dimensional problem, we address s-wave collisions in three dimensions and relate the bare lattice coupling constants to the continuum coupling...
Rapid Separation of Disconnected Triangle Meshes Based on Graph Traversal
International Nuclear Information System (INIS)
Ji, S J; Wang, Y
2006-01-01
In recent year, The STL file become a de facto standard on the file presentation in CAD/CAM, computer graph and reverse engineering. When point cloud which is obtained by scanning object body using optical instrument is used to reconstruct an original model, the points cloud is presented by the STL file. Usually, datum of several separated and relative objects are stored in a single STL file, when such a file is operated by a computer, the datum in the file is firstly separated and then each element of every triangle pitch on the triangle mesh is traversed and visited and is calculated. The problem is analyzed and studied by many experts, but there is still a lack of a simple and quick algorithm. An algorithm which uses graph traversal to traverse each element of the triangle meshes and separate several disconnected triangle meshes is presented by the paper, the searching and calculating speed of the data on the triangle meshes is enhanced, memory size of the computer is reduced, complexity of the data structure is simplified and powerful guarantee is made for the next process by using this algorithm
International Nuclear Information System (INIS)
Mack, G.
1982-01-01
After a description of a pure Yang-Mills theory on a lattice, the author considers a three-dimensional pure U(1) lattice gauge theory. Thereafter he discusses the exact relation between lattice gauge theories with the gauge groups SU(2) and SO(3). Finally he presents Monte Carlo data on phase transitions in SU(2) and SO(3) lattice gauge models. (HSI)
Triangle inequalities in coherence measures and entanglement concurrence
Dai, Yue; You, Wenlong; Dong, Yuli; Zhang, Chengjie
2017-12-01
We provide detailed proofs of triangle inequalities in coherence measures and entanglement concurrence. If a rank-2 state ϱ can be expressed as a convex combination of two pure states, i.e., ϱ =p1| ψ1〉〈 ψ1|+ p2| ψ2〉〈 ψ2| , a triangle inequality can be established as |E (|Ψ1〉 )-E (|Ψ2〉 )|≤E (ϱ ) ≤E (|Ψ1〉 )+E (|Ψ2〉 ) , where | Ψ1〉= √{p1}|ψ1〉 and | Ψ2〉= √{p2}|ψ2〉 ; E can be considered either coherence measures or entanglement concurrence. This inequality displays mathematical beauty for its similarity to the triangle inequality in plane geometry. An illustrative example is given after the proof.
Value Triangles in the Management of Building Projects
DEFF Research Database (Denmark)
Jensen, Per Anker
2013-01-01
The purpose of this paper is to investigate value triangles and their implementation in the management of building projects. The paper is based on results from a research project on space strategies and building values, which included a major case study of the development of facilities for Danish...... Broadcasting Corporation (DR) over time. The conventional iron triangle of quality, cost and schedule for project management is the theoretical starting point, but this is seen as mainly being related to process integrity in the construction stage. It is supplemented by a similar value triangle of cultural...... value, use value and quality of realization for product integrity, mainly for the design stage. Based on this framework an evaluation is made of the value management in six of DR’s building projects from the first around 1930 to the most recent – the new headquarters DR Byen finalised in 2009...
Steam and electroheating remediation of tight soils
Energy Technology Data Exchange (ETDEWEB)
Balshaw-Biddle, K.; Oubre, C.L.; Ward, C.H. [eds.; Dablow, J.F. III; Pearce, J.A.; Johnson, P.C.
2000-07-01
In the past few decades the need for soil remediation has become urgent, even more necessary--innovative, cost effective methods. Steam and Electroheating Remediation of Tight Soils presents the results of a field study testing the cleanup of semi-volatile fuels from tight soils using combination of hydraulic fracturing and soil heating technologies.
Some constructions on total labelling of m triangles
Energy Technology Data Exchange (ETDEWEB)
Voon, Chen Huey, E-mail: chenhv@utar.edu.my; Hui, Liew How, E-mail: liewhh@utar.edu.my; How, Yim Kheng, E-mail: tidusyimhome@hotmail.com [Department of Mathematical and Actuarial Sciences, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Sungai Long, Bandar Sungai Long, Cheras 43000 Kajang, Selangor (Malaysia)
2016-06-02
Let mK{sub 3} = (V{sub m}, E{sub m}) be a finite disconnected graph consisting of m disjoint triangles K{sub 3}, where V{sub m} is the set of vertices, E{sub m} is the set of edges and both V{sub m} and E{sub m} are of the same size 3m. A total labelling of mK{sub 3} is a function f which maps the elements in V{sub m} and E{sub m} to positive integer values, i.e. f : V{sub m} ∪ E{sub m} → {1, 2, 3,···}. Let c be a positive integer. A triangle is said have a c-Erdősian triangle labelling if it is a total labelling f : V{sub m} ∪ E{sub m} → {c, c + 1, ···, c + 6m − 1} such that f (x) + f (y) = f (xy) for any x, y ∈ V{sub m} and an edge xy ∈ E{sub m} joining them. In order to find all the c-Erdősian triangle labelling, a straightforward is to use the exhaustive search. However, the exhaustive search is only able to find c-Erdősian triangle labelling for m ≤ 5 due to combinatorial explosion. By studying the constant sum of vertex labels, we propose a strong permutation approach, which allows us to generate a certain classes of c-Erdősian triangle labelling up until m = 8.
Some constructions on total labelling of m triangles
International Nuclear Information System (INIS)
Voon, Chen Huey; Hui, Liew How; How, Yim Kheng
2016-01-01
Let mK_3 = (V_m, E_m) be a finite disconnected graph consisting of m disjoint triangles K_3, where V_m is the set of vertices, E_m is the set of edges and both V_m and E_m are of the same size 3m. A total labelling of mK_3 is a function f which maps the elements in V_m and E_m to positive integer values, i.e. f : V_m ∪ E_m → {1, 2, 3,···}. Let c be a positive integer. A triangle is said have a c-Erdősian triangle labelling if it is a total labelling f : V_m ∪ E_m → {c, c + 1, ···, c + 6m − 1} such that f (x) + f (y) = f (xy) for any x, y ∈ V_m and an edge xy ∈ E_m joining them. In order to find all the c-Erdősian triangle labelling, a straightforward is to use the exhaustive search. However, the exhaustive search is only able to find c-Erdősian triangle labelling for m ≤ 5 due to combinatorial explosion. By studying the constant sum of vertex labels, we propose a strong permutation approach, which allows us to generate a certain classes of c-Erdősian triangle labelling up until m = 8.
Vertex Normals and Face Curvatures of Triangle Meshes
Sun, Xiang
2016-08-12
This study contributes to the discrete differential geometry of triangle meshes, in combination with discrete line congruences associated with such meshes. In particular we discuss when a congruence defined by linear interpolation of vertex normals deserves to be called a ŉormal’ congruence. Our main results are a discussion of various definitions of normality, a detailed study of the geometry of such congruences, and a concept of curvatures and shape operators associated with the faces of a triangle mesh. These curvatures are compatible with both normal congruences and the Steiner formula.
Lattices with unique complements
Saliĭ, V N
1988-01-01
The class of uniquely complemented lattices properly contains all Boolean lattices. However, no explicit example of a non-Boolean lattice of this class has been found. In addition, the question of whether this class contains any complete non-Boolean lattices remains unanswered. This book focuses on these classical problems of lattice theory and the various attempts to solve them. Requiring no specialized knowledge, the book is directed at researchers and students interested in general algebra and mathematical logic.
A New and Very Long Proof of the Pythagoras Theorem By Way of a Proposition on Isosceles Triangles
Basu, Kaushik
2015-01-01
This paper provides a new proof of the Pythagoras Theorem on right-angled triangles via two new lemmas pertaining to, respectively, isosceles triangles and right-angled triangles, which are of pedagogical value in themselves.
The coral triangle initiative: What are we missing? A case study from Aceh
Rudi, Edi; Campbell, Stuart J.; Hoey, Andrew; Fadli, Nur; Linkie, Matthew; Baird, Andrew Hamilton
2012-01-01
Abstract The Coral Triangle Initiative is an ambitious attempt to conserve the marine biodiversity hotspot known as the Coral Triangle. However, the reef fauna in many nearby regions remains poorly explored and, consequently, the focus on the Coral
Knowledge triangles in the Netherlands : an entrepreneurial ecosystem approach
Stam, E.; Romme, A.G.L.; Roso, M.; van den Toren, J.P.; van der Starre, B.T.
2016-01-01
This is a study of the knowledge triangles of research-education-innovation in several Dutch regional ecosystems. It draws on case studies of the Amsterdam, Twente and Eindhoven regions as well as the analysis of secondary data regarding a larger set of regional ecosystems in the Netherlands.
Triangle of Safety Technique: A New Approach to Laparoscopic Cholecystectomy
Directory of Open Access Journals (Sweden)
Abdulrahman F. M. S. Almutairi
2009-01-01
dissection of the Calot's triangle can lead to such injuries. The aim of the authors in this study is to present a new safe triangle of dissection. Patients and Method. 501 patients under went LC in the following approach; The cystic artery is identified and mobilized from the gall bladder (GB medial wall down towards the cystic duct which would simultaneously divide the medial GB peritoneal attachment. This is then followed by dividing the lateral peritoneal attachment. The GB will be unfolded and the borders of the triangle of safety (TST are achieved: cystic artery medially, cystic duct laterally and the gallbladder wall superiorly. The floor of the triangle is then divided to delineate both cystic duct and artery in an area relatively far from CBD. Results. There were little significant immediate or delayed complications. The mean operating time was 68 minutes, nearly equivalent to the conventional method. Conclusions. Dissection at TST appears to be a safe procedure which clearly demonstrates the cystic duct and may help to reduce the CBD injuries.
The chemist's triangle and a general systemic approach to teaching ...
African Journals Online (AJOL)
The three levels of science thought (macro, micro, symbolic), identified by Johnstone and represented by a triangle, may be viewed as a core closed-cluster concept map of the type advocated in the systemic approach to teaching and learning of chemistry. Some of the implications of this view for teaching, learning and ...
Rates of convergence of Brezier net over triangles
International Nuclear Information System (INIS)
Feng Yuyu.
1986-12-01
It is well known (Farin, 1979) that the sequence of Bezier nets f-circumflex n (x) associated with Bernstein-Bezier surface over a triangle converges to the surface uniformly as n goes to infinity. In this paper the precise rates of convergence are given. The pointwise convergence result and saturation theorem are presented. (author). 7 refs
Enriching Triangle Mesh Animations with Physically Based Simulation.
Li, Yijing; Xu, Hongyi; Barbic, Jernej
2017-10-01
We present a system to combine arbitrary triangle mesh animations with physically based Finite Element Method (FEM) simulation, enabling control over the combination both in space and time. The input is a triangle mesh animation obtained using any method, such as keyframed animation, character rigging, 3D scanning, or geometric shape modeling. The input may be non-physical, crude or even incomplete. The user provides weights, specified using a minimal user interface, for how much physically based simulation should be allowed to modify the animation in any region of the model, and in time. Our system then computes a physically-based animation that is constrained to the input animation to the amount prescribed by these weights. This permits smoothly turning physics on and off over space and time, making it possible for the output to strictly follow the input, to evolve purely based on physically based simulation, and anything in between. Achieving such results requires a careful combination of several system components. We propose and analyze these components, including proper automatic creation of simulation meshes (even for non-manifold and self-colliding undeformed triangle meshes), converting triangle mesh animations into animations of the simulation mesh, and resolving collisions and self-collisions while following the input.
From the Triangle Inequality to the Isoperimetric Inequality
Indian Academy of Sciences (India)
IAS Admin
Calculus of variations, shape optimization, isoperimetric prob- lems. Figure 1. Starting from the triangle inequality, we will dis- cuss a series of shape optimization problems us- ing elementary geometry and ultimately derive the classical isoperimetric inequality in the plane. One of the important results we learn in plane geom ...
Self-assembly of self-assembled molecular triangles
Indian Academy of Sciences (India)
While the solution state structure of 1 can be best described as a trinuclear complex, in the solidstate well-fashioned intermolecular - and CH- interactions are observed. Thus, in the solid-state further self-assembly of already self-assembled molecular triangle is witnessed. The triangular panels are arranged in a linear ...
From the Triangle Inequality to the Isoperimetric Inequality
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 2. From the Triangle Inequality to the Isoperimetric Inequality. S Kesavan. General Article Volume 19 Issue 2 February 2014 pp 135-148. Fulltext. Click here to view fulltext PDF. Permanent link:
Long-Lived Feshbach Molecules in a Three-Dimensional Optical Lattice
International Nuclear Information System (INIS)
Thalhammer, G.; Winkler, K.; Lang, F.; Schmid, S.; Denschlag, J. Hecker; Grimm, R.
2006-01-01
We have created and trapped a pure sample of 87 Rb 2 Feshbach molecules in a three-dimensional optical lattice. Compared to previous experiments without a lattice, we find dramatic improvements such as long lifetimes of up to 700 ms and a near unit efficiency for converting tightly confined atom pairs into molecules. The lattice shields the trapped molecules from collisions and, thus, overcomes the problem of inelastic decay by vibrational quenching. Furthermore, we have developed an advanced purification scheme that removes residual atoms, resulting in a lattice in which individual sites are either empty or filled with a single molecule in the vibrational ground state of the lattice
Identifying translational science within the triangle of biomedicine.
Weber, Griffin M
2013-05-24
The National Institutes of Health (NIH) Roadmap places special emphasis on "bench-to-bedside" research, or the "translation" of basic science research into practical clinical applications. The Clinical and Translational Science Awards (CTSA) Consortium is one example of the large investments being made to develop a national infrastructure to support translational science, which involves reducing regulatory burdens, launching new educational initiatives, and forming partnerships between academia and industry. However, while numerous definitions have been suggested for translational science, including the qualitative T1-T4 classification, a consensus has not yet been reached. This makes it challenging to tract the impact of these major policy changes. In this study, we use a bibliometric approach to map PubMed articles onto a graph, called the Triangle of Biomedicine. The corners of the triangle represent research related to animals, cells and molecules, and humans; and, the position of a publication on the graph is based on its topics, as determined by its Medical Subject Headings (MeSH). We define translation as movement of a collection of articles, or the articles that cite those articles, towards the human corner. The Triangle of Biomedicine provides a quantitative way of determining if an individual scientist, research organization, funding agency, or scientific field is producing results that are relevant to clinical medicine. We validate our technique using examples that have been previously described in the literature and by comparing it to prior methods of measuring translational science. The Triangle of Biomedicine is a novel way to identify translational science and track changes over time. This is important to policy makers in evaluating the impact of the large investments being made to accelerate translation. The Triangle of Biomedicine also provides a simple visual way of depicting this impact, which can be far more powerful than numbers alone.
A Classroom Note on Generating Examples for the Laws of Sines and Cosines from Pythagorean Triangles
Sher, Lawrence; Sher, David
2007-01-01
By selecting certain special triangles, students can learn about the laws of sines and cosines without wrestling with long decimal representations or irrational numbers. Since the law of cosines requires only one of the three angles of a triangle, there are many examples of triangles with integral sides and a cosine that can be represented exactly…
Tight connection between fission gas discharge channels
International Nuclear Information System (INIS)
Jung, W.; Peehs, M.; Rau, P.; Krug, W.; Stechemesser, H.
1978-01-01
The invention is concerned with the tight connection between the fission gas discharge channel, leading away from the support plate of a gas-cooled reactor, and the top of the fuel element suspended from this support plate. The closure is designed to be gas-tight for the suspended as well as for the released fuel element. The tight connection has got an annular body resting on the core support plate in the mouth region of the fission gas discharge channel. This body is connected with the fission gas discharge channel in the fuel element top fitting via a gas-tight part and supported by a compression spring. Care is taken for sealing if the fuel element is removal. (RW) [de
New integrable lattice hierarchies
International Nuclear Information System (INIS)
Pickering, Andrew; Zhu Zuonong
2006-01-01
In this Letter we give a new integrable four-field lattice hierarchy, associated to a new discrete spectral problem. We obtain our hierarchy as the compatibility condition of this spectral problem and an associated equation, constructed herein, for the time-evolution of eigenfunctions. We consider reductions of our hierarchy, which also of course admit discrete zero curvature representations, in detail. We find that our hierarchy includes many well-known integrable hierarchies as special cases, including the Toda lattice hierarchy, the modified Toda lattice hierarchy, the relativistic Toda lattice hierarchy, and the Volterra lattice hierarchy. We also obtain here a new integrable two-field lattice hierarchy, to which we give the name of Suris lattice hierarchy, since the first equation of this hierarchy has previously been given by Suris. The Hamiltonian structure of the Suris lattice hierarchy is obtained by means of a trace identity formula
Lattice gas simulations of dynamical geometry in two dimensions.
Klales, Anna; Cianci, Donato; Needell, Zachary; Meyer, David A; Love, Peter J
2010-10-01
We present a hydrodynamic lattice gas model for two-dimensional flows on curved surfaces with dynamical geometry. This model is an extension to two dimensions of the dynamical geometry lattice gas model previously studied in one dimension. We expand upon a variation of the two-dimensional flat space Frisch-Hasslacher-Pomeau (FHP) model created by Frisch [Phys. Rev. Lett. 56, 1505 (1986)] and independently by Wolfram, and modified by Boghosian [Philos. Trans. R. Soc. London, Ser. A 360, 333 (2002)]. We define a hydrodynamic lattice gas model on an arbitrary triangulation whose flat space limit is the FHP model. Rules that change the geometry are constructed using the Pachner moves, which alter the triangulation but not the topology. We present results on the growth of the number of triangles as a function of time. Simulations show that the number of triangles grows with time as t(1/3), in agreement with a mean-field prediction. We also present preliminary results on the distribution of curvature for a typical triangulation in these simulations.
Few quantum particles on one dimensional lattices
International Nuclear Information System (INIS)
Valiente Cifuentes, Manuel
2010-01-01
There is currently a great interest in the physics of degenerate quantum gases and low-energy few-body scattering due to the recent experimental advances in manipulation of ultracold atoms by light. In particular, almost perfect periodic potentials, called optical lattices, can be generated. The lattice spacing is fixed by the wavelength of the laser field employed and the angle betwen the pair of laser beams; the lattice depth, defining the magnitude of the different band gaps, is tunable within a large interval of values. This flexibility permits the exploration of different regimes, ranging from the ''free-electron'' picture, modified by the effective mass for shallow optical lattices, to the tight-binding regime of a very deep periodic potential. In the latter case, effective single-band theories, widely used in condensed matter physics, can be implemented with unprecedent accuracy. The tunability of the lattice depth is nowadays complemented by the use of magnetic Feshbach resonances which, at very low temperatures, can vary the relevant atom-atom scattering properties at will. Moreover, optical lattices loaded with gases of effectively reduced dimensionality are experimentally accessible. This is especially important for one spatial dimension, since most of the exactly solvable models in many-body quantum mechanics deal with particles on a line; therefore, experiments with one-dimensional gases serve as a testing ground for many old and new theories which were regarded as purely academic not so long ago. The physics of few quantum particles on a one-dimensional lattice is the topic of this thesis. Most of the results are obtained in the tight-binding approximation, which is amenable to exact numerical or analytical treatment. For the two-body problem, theoretical methods for calculating the stationary scattering and bound states are developed. These are used to obtain, in closed form, the two-particle solutions of both the Hubbard and extended Hubbard models
Few quantum particles on one dimensional lattices
Energy Technology Data Exchange (ETDEWEB)
Valiente Cifuentes, Manuel
2010-06-18
There is currently a great interest in the physics of degenerate quantum gases and low-energy few-body scattering due to the recent experimental advances in manipulation of ultracold atoms by light. In particular, almost perfect periodic potentials, called optical lattices, can be generated. The lattice spacing is fixed by the wavelength of the laser field employed and the angle betwen the pair of laser beams; the lattice depth, defining the magnitude of the different band gaps, is tunable within a large interval of values. This flexibility permits the exploration of different regimes, ranging from the ''free-electron'' picture, modified by the effective mass for shallow optical lattices, to the tight-binding regime of a very deep periodic potential. In the latter case, effective single-band theories, widely used in condensed matter physics, can be implemented with unprecedent accuracy. The tunability of the lattice depth is nowadays complemented by the use of magnetic Feshbach resonances which, at very low temperatures, can vary the relevant atom-atom scattering properties at will. Moreover, optical lattices loaded with gases of effectively reduced dimensionality are experimentally accessible. This is especially important for one spatial dimension, since most of the exactly solvable models in many-body quantum mechanics deal with particles on a line; therefore, experiments with one-dimensional gases serve as a testing ground for many old and new theories which were regarded as purely academic not so long ago. The physics of few quantum particles on a one-dimensional lattice is the topic of this thesis. Most of the results are obtained in the tight-binding approximation, which is amenable to exact numerical or analytical treatment. For the two-body problem, theoretical methods for calculating the stationary scattering and bound states are developed. These are used to obtain, in closed form, the two-particle solutions of both the Hubbard and
Energy spectrum of two-dimensional tight-binding electrons in a spatially varying magnetic field
International Nuclear Information System (INIS)
Oh, G.Y.; Lee, M.H.
1996-01-01
The electronic energy spectrum of a two-dimensional lattice in a spatially varying magnetic field is studied within the framework of the tight-binding model by using the scheme of the transfer matrix. It is found that, in comparison with the case of a uniform magnetic field, the energy spectrum exhibits more complicated behavior; band broadening (or gap closing) and band splitting (or gap opening) occur depending on characteristic parameters of the lattice. The origin of these phenomena lies in the existence of direct touching and indirect overlapping between neighboring subbands. Dependence of direct touching and indirect overlapping, and thus the electronic band structure together with the density of states, on characteristic parameters of the lattice is elucidated in detail. copyright 1996 The American Physical Society
Persistent current in triangle silicene rings with spin–orbit interaction
Energy Technology Data Exchange (ETDEWEB)
Xu, Ning, E-mail: nxu@ycit.cn [Department of Physics, Yancheng Institute of Technology, Yancheng 224051 (China); Zhang, Haiyang; Wu, Xiuqiang; Bai, Yujie [Department of Physics, Yancheng Institute of Technology, Yancheng 224051 (China); Ding, Jianwen, E-mail: jwding@xtu.edu.cn [Department of Physics, Xiangtan University, Xiangtan 411105 (China)
2017-06-28
The energy spectrum and magnetic response of triangle silicene rings (TSRs) are investigated within the tight-binding model. It is shown that the flux-dependent energy spectrum is divided into bands, with three levels per band, owing to the three-fold rotational symmetry structure of TSRs. The zigzag TSRs are metallic, exhibiting either diamagnetic or paramagnetic response depending on the size of inner ring radius. Armchair TSRs are semiconducting, exhibiting diamagnetic response. Taking into account the intrinsic spin–orbit interaction, the magnetic-field-driven spin-up electrons flow anticlockwise around the TSRs and the spin-down electrons flow clockwise around the TSRs. Additionally, paramagnetism–diamagnetism or diamagnetism–paramagnetism transitions are observed with the increase of exchange field. The results may be very helpful for the design and application of TSR-based nanodevices. - Highlights: • The zigzag TSRs are metallic. • Armchair TSRs which exhibit diamagnetic response are semiconducting. • The spin-up electrons flow anticlockwise and spin-down electrons flow clockwise around the rings.
Visualization on triangle concept using Adobe Flash Professional SC6
Sagita, Laela; Ratih Kusumarini, Adha
2017-12-01
The purpose of this paper is to develop teaching aids using Adobe Flash Professional CS6 emphasize on Triangle concept. A new alternative way to deliver a basic concept in geometry with visualization is software Adobe Flash Professional CS 6. Research method is research and development with 5 phase of Ploom’s model, namely (1) preliminary, (2) design, (3) realization/ construction, (4) test, evaluation and revision, and 5) implementation. The results showed that teaching aids was valid, practice, and effective. Validity: expert judgement for material score is 3.95 and media expert judgement produce an average score of 3,2, both in the category are valid. Practically: the average of questionnaire response is 4,04 (good). Effectiveness: n-gain test value is 0,36 (medium). It concluded that developed of teaching aids using Adobe Flash CS6 on triangle can improve student achievement.
Freud, Ferenczi, and Rosmersholm: incestuous triangles and analytic thirds.
Rudnytsky, Peter L
2013-12-01
Utilizing a field theory of unconscious communication, and in particular the concept of the analytic third, this paper situates Freud's interpretation of Ibsen's 1886 Rosmersholm, presented in the section of his essay "Some Character-Types Met with in Psycho-Analytic Work" (1916) entitled "Those Wrecked by Success," in the context of his relationship with Ferenczi. Both in his interpretation of Rosmersholm and in his earlier papers on the psychology of love, it is argued, Freud may be seen to commenting both on Ferenczi's incestuous love triangle with Gizella and Elma Pálos and on his equally incestuous triangle with Martha and Minna Bernays. In a postscript, the challenge offered by Groddeck to Freud's oedipal reading of Rosmersholm is assessed.
Generalized isothermic lattices
International Nuclear Information System (INIS)
Doliwa, Adam
2007-01-01
We study multi-dimensional quadrilateral lattices satisfying simultaneously two integrable constraints: a quadratic constraint and the projective Moutard constraint. When the lattice is two dimensional and the quadric under consideration is the Moebius sphere one obtains, after the stereographic projection, the discrete isothermic surfaces defined by Bobenko and Pinkall by an algebraic constraint imposed on the (complex) cross-ratio of the circular lattice. We derive the analogous condition for our generalized isothermic lattices using Steiner's projective structure of conics, and we present basic geometric constructions which encode integrability of the lattice. In particular, we introduce the Darboux transformation of the generalized isothermic lattice and we derive the corresponding Bianchi permutability principle. Finally, we study two-dimensional generalized isothermic lattices, in particular geometry of their initial boundary value problem
Anatomic Assessment of Variations in Kambin's Triangle: A Surgical and Cadaver Study.
Ozer, Ali Fahir; Suzer, Tuncer; Can, Halil; Falsafi, Mani; Aydin, Murat; Sasani, Mehdi; Oktenoglu, Tunc
2017-04-01
The relationship of exiting root and Kambin's triangle is discussed in this article. Transforaminal endoscopic surgery as the gold standard of less invasive lumbar disc surgeries is performed through Kambin's triangle. Existing root damage is one of the most important complication for this type of surgery. Anatomic variations in Kambin's triangle may be the main reason for nerve root damage during endoscopic lumbar disc surgery. Kambin's triangle was investigated with surgical views and cadaver studies. Thirty-four patients with far lateral disc herniation were treated with an extraforaminal approach under the microscope. On the other hand, 48 Kambin's triangles were dissected on 8 cadavers. Three main types of triangle were identified, and patients were grouped according to these 3 types of the triangle. Only 6 of the 34 patients had type 3 triangles, which is the wide classical triangle described by Kambin; however, 17 patients had type 2, with a narrow space in the triangle, and 11 patients had type 1, with no space inside the triangle. Cadaver results were similar; only 10 of the 48 specimens had the type 3 classical triangle, whereas 23 specimens had type 2, and 15 specimens had type 1 triangles. Our results disclosed narrowed or no space in 82.4% of the patients and 79.2% of the cadavers. We observed that a wide and safe room of the triangle may not be exist in some patients. Therefore, more care must be taken during endoscopic lumbar disc surgery to avoid nerve damage. Copyright © 2017 Elsevier Inc. All rights reserved.
Numerical problems with the Pascal triangle in moment computation
Czech Academy of Sciences Publication Activity Database
Kautsky, J.; Flusser, Jan
2016-01-01
Roč. 306, č. 1 (2016), s. 53-68 ISSN 0377-0427 R&D Projects: GA ČR GA15-16928S Institutional support: RVO:67985556 Keywords : moment computation * Pascal triangle * appropriate polynomial basis * numerical problems Subject RIV: JD - Computer Applications, Robotics Impact factor: 1.357, year: 2016 http://library.utia.cas.cz/separaty/2016/ZOI/flusser-0459096.pdf
Sequential Triangle Strip Generator based on Hopfield Networks
Czech Academy of Sciences Publication Activity Database
Šíma, Jiří; Lněnička, Radim
2009-01-01
Roč. 21, č. 2 (2009), s. 583-617 ISSN 0899-7667 R&D Projects: GA MŠk(CZ) 1M0545; GA AV ČR 1ET100300517; GA MŠk 1M0572 Institutional research plan: CEZ:AV0Z10300504; CEZ:AV0Z10750506 Keywords : sequential triangle strip * combinatorial optimization * Hopfield network * minimum energy * simulated annealing Subject RIV: IN - Informatics, Computer Science Impact factor: 2.175, year: 2009
The phases of large networks with edge and triangle constraints
Kenyon, Richard; Radin, Charles; Ren, Kui; Sadun, Lorenzo
2017-10-01
Based on numerical simulation and local stability analysis we describe the structure of the phase space of the edge/triangle model of random graphs. We support simulation evidence with mathematical proof of continuity and discontinuity for many of the phase transitions. All but one of the many phase transitions in this model break some form of symmetry, and we use this model to explore how changes in symmetry are related to discontinuities at these transitions.
Vaal Triangle air pollution health study. Addressing South African problems
Energy Technology Data Exchange (ETDEWEB)
Terblanche, P; Nel, R [CSIR Environmental Services, Pretoria (South Africa); Surridge, T [Dept. of Mineral and Energy Affairs (South Africa); Annegarn, H [Annegarn Environmental Research, Johannesburg (South Africa); Tosen, G [Eskom, Johannesburg (South Africa); Pols, A [CSIR Informationtek, Pretoria (South Africa)
1996-12-31
Situated in the central region of South Africa, the Vaal Triangle is an area which plays a vital role in driving the economic dynamo of South Africa. Also, because of the concentration of heavy industry, it is an area which provides a challenge in effective air pollution control. The Vaal Triangle lies within the Vaal River Basin, at an altitude of 1 500 m above sea level. Meteorological conditions in the area are highly conducive to the formation of surface temperature inversions, resulting in a poor dispersion potential. Because of multiple sources of air pollution in the area, poor dispersion conditions increase the risk pollution build-up and subsequent adverse impacts. The situation is further exacerbated by the continued combustion of coal in households, even after the electrification of residences. This is particularly chronic in the developing communities and during winter. Vaal Triangle Air Pollution Health Study (VAPS) was initiated in 1990 by the Department of Health, the Medical Research Council and major industries in the area to determine effects of air pollution on the health of the community. The final results of that study summarised in this article, and options to ameliorate problems are addressed. (author)
Vaal Triangle air pollution health study. Addressing South African problems
Energy Technology Data Exchange (ETDEWEB)
Terblanche, P.; Nel, R. [CSIR Environmental Services, Pretoria (South Africa); Surridge, T. [Dept. of Mineral and Energy Affairs (South Africa); Annegarn, H. [Annegarn Environmental Research, Johannesburg (South Africa); Tosen, G. [Eskom, Johannesburg (South Africa); Pols, A. [CSIR Informationtek, Pretoria (South Africa)
1995-12-31
Situated in the central region of South Africa, the Vaal Triangle is an area which plays a vital role in driving the economic dynamo of South Africa. Also, because of the concentration of heavy industry, it is an area which provides a challenge in effective air pollution control. The Vaal Triangle lies within the Vaal River Basin, at an altitude of 1 500 m above sea level. Meteorological conditions in the area are highly conducive to the formation of surface temperature inversions, resulting in a poor dispersion potential. Because of multiple sources of air pollution in the area, poor dispersion conditions increase the risk pollution build-up and subsequent adverse impacts. The situation is further exacerbated by the continued combustion of coal in households, even after the electrification of residences. This is particularly chronic in the developing communities and during winter. Vaal Triangle Air Pollution Health Study (VAPS) was initiated in 1990 by the Department of Health, the Medical Research Council and major industries in the area to determine effects of air pollution on the health of the community. The final results of that study summarised in this article, and options to ameliorate problems are addressed. (author)
Strong dynamics and lattice gauge theory
Schaich, David
In this dissertation I use lattice gauge theory to study models of electroweak symmetry breaking that involve new strong dynamics. Electroweak symmetry breaking (EWSB) is the process by which elementary particles acquire mass. First proposed in the 1960s, this process has been clearly established by experiments, and can now be considered a law of nature. However, the physics underlying EWSB is still unknown, and understanding it remains a central challenge in particle physics today. A natural possibility is that EWSB is driven by the dynamics of some new, strongly-interacting force. Strong interactions invalidate the standard analytical approach of perturbation theory, making these models difficult to study. Lattice gauge theory is the premier method for obtaining quantitatively-reliable, nonperturbative predictions from strongly-interacting theories. In this approach, we replace spacetime by a regular, finite grid of discrete sites connected by links. The fields and interactions described by the theory are likewise discretized, and defined on the lattice so that we recover the original theory in continuous spacetime on an infinitely large lattice with sites infinitesimally close together. The finite number of degrees of freedom in the discretized system lets us simulate the lattice theory using high-performance computing. Lattice gauge theory has long been applied to quantum chromodynamics, the theory of strong nuclear interactions. Using lattice gauge theory to study dynamical EWSB, as I do in this dissertation, is a new and exciting application of these methods. Of particular interest is non-perturbative lattice calculation of the electroweak S parameter. Experimentally S ≈ -0.15(10), which tightly constrains dynamical EWSB. On the lattice, I extract S from the momentum-dependence of vector and axial-vector current correlators. I created and applied computer programs to calculate these correlators and analyze them to determine S. I also calculated the masses
An introduction to finite tight frames
Waldron, Shayne F D
2018-01-01
This textbook is an introduction to the theory and applications of finite tight frames, an area that has developed rapidly in the last decade. Stimulating much of this growth are the applications of finite frames to diverse fields such as signal processing, quantum information theory, multivariate orthogonal polynomials, and remote sensing. Key features and topics: * First book entirely devoted to finite frames * Extensive exercises and MATLAB examples for classroom use * Important examples, such as harmonic and Heisenberg frames, are presented in preliminary chapters, encouraging readers to explore and develop an intuitive feeling for tight frames * Later chapters delve into general theory details and recent research results * Many illustrations showing the special aspects of the geometry of finite frames * Provides an overview of the field of finite tight frames * Discusses future research directions in the field Featuring exercises and MATLAB examples in each chapter, the book is well suited as a textbook ...
Hermetic compartments leak-tightness enhancement
International Nuclear Information System (INIS)
Murani, J.
2000-01-01
In connection with the enhancement of the nuclear safety of the Jaslovske Bohunice V-1 NPP actions for the increase of the leak tightness are performed. The reconstruction has been done in the following directions: hermetic compartments leak tightness enhancement; air lock installation; installation of air lock in SP 4 vent system; integrated leakage rate test to hermetic compartments with leak detection. After 'major' leaks on the hermetic boundary components had been eliminated, since 1994 works on a higher qualitative level began. The essence of the works consists in the detection and identification of leaks in the structural component of the hermetic boundary during the planned refueling outages. The results of the Small Reconstruction and gradual enhancement of leak tightness are presented
Saturnian north polar region: a triangle inside the hexagon?
Kochemasov, Gennady G.
2010-05-01
The famous and "mysterious" stable hexagon structure around the North Pole of Saturn was earlier interpreted as projections of faces of a structural tetrahedron [1]. This "hidden" simplest Plato's polyhedron is a result of an interference of four fundamental (wave 1) warping waves having in any rotating celestial body four directions: orthogonal and diagonal. Origin of the warping waves in any celestial body is due to their movements in elliptical keplerian orbits with periodically changing accelerations. The structural tetrahedron is an intrinsic geometric feature marking the celestial bodies ubiquitous tectonic dichotomy as in a tetrahedron always there is an opposition of a face (expansion) and a vertex (contraction). In the saturnian case the tetrahedron shows a face at the north and a vertex at the south. Morphologically this is manifested by the hexagon and opposing it in the south a vertex. Blue and pink hues of the northern and southern hemispheres also underline the tectonic dichotomy. These geometric expressions are enforced by a subtle dark equilateral triangle appearing in the image PIA11682 also around the north pole and inside the hexagon (the triangle side is about 15000 km long). One angle of the triangle is clearly visible, another one just shows itself and the third one is barely distinguished. The sides of the triangle are not strait lines but slightly broken amidst lines what makes the triangle appear a bit hexagonal (spherical) and the angle is a bit bigger than 60 degrees of a classical equilateral triangle (~70 degrees). The central part of the triangle is not imaged (a black hole in the PIA11682). This image also confirms that the wide northern polar region is also densely "peppered" with bright cloudy more or less isometric spots on average 400 to 800 km across as in other latitudinal belts of Saturn [2, 3, 4]. Earlier they were observed in IR wavelengths, now they show themselves in visible wavelengths. Their origin and size were
Energy Technology Data Exchange (ETDEWEB)
Lillie, R.A.; Robinson, J.C.
1976-05-01
The discrete ordinates method is the most powerful and generally used deterministic method to obtain approximate solutions of the Boltzmann transport equation. A finite element formulation, utilizing a canonical form of the transport equation, is here developed to obtain both integral and pointwise solutions to neutron transport problems. The formulation is based on the use of linear triangles. A general treatment of anisotropic scattering is included by employing discrete ordinates-like approximations. In addition, multigroup source outer iteration techniques are employed to perform group-dependent calculations. The ability of the formulation to reduce substantially ray effects and its ability to perform streaming calculations are demonstrated by analyzing a series of test problems. The anisotropic scattering and multigroup treatments used in the development of the formulation are verified by a number of one-dimensional comparisons. These comparisons also demonstrate the relative accuracy of the formulation in predicting integral parameters. The applicability of the formulation to nonorthogonal planar geometries is demonstrated by analyzing a hexagonal-type lattice. A small, high-leakage reactor model is analyzed to investigate the effects of varying both the spatial mesh and order of angular quadrature. This analysis reveals that these effects are more pronounced in the present formulation than in other conventional formulations. However, the insignificance of these effects is demonstrated by analyzing a realistic reactor configuration. In addition, this final analysis illustrates the importance of incorporating anisotropic scattering into the finite element formulation. 8 tables, 29 figures.
International Nuclear Information System (INIS)
Lillie, R.A.; Robinson, J.C.
1976-05-01
The discrete ordinates method is the most powerful and generally used deterministic method to obtain approximate solutions of the Boltzmann transport equation. A finite element formulation, utilizing a canonical form of the transport equation, is here developed to obtain both integral and pointwise solutions to neutron transport problems. The formulation is based on the use of linear triangles. A general treatment of anisotropic scattering is included by employing discrete ordinates-like approximations. In addition, multigroup source outer iteration techniques are employed to perform group-dependent calculations. The ability of the formulation to reduce substantially ray effects and its ability to perform streaming calculations are demonstrated by analyzing a series of test problems. The anisotropic scattering and multigroup treatments used in the development of the formulation are verified by a number of one-dimensional comparisons. These comparisons also demonstrate the relative accuracy of the formulation in predicting integral parameters. The applicability of the formulation to nonorthogonal planar geometries is demonstrated by analyzing a hexagonal-type lattice. A small, high-leakage reactor model is analyzed to investigate the effects of varying both the spatial mesh and order of angular quadrature. This analysis reveals that these effects are more pronounced in the present formulation than in other conventional formulations. However, the insignificance of these effects is demonstrated by analyzing a realistic reactor configuration. In addition, this final analysis illustrates the importance of incorporating anisotropic scattering into the finite element formulation. 8 tables, 29 figures
Lattice theory for nonspecialists
International Nuclear Information System (INIS)
Hari Dass, N.D.
1984-01-01
These lectures were delivered as part of the academic training programme at the NIKHEF-H. These lectures were intended primarily for experimentalists, and theorists not specializing in lattice methods. The goal was to present the essential spirit behind the lattice approach and consequently the author has concentrated mostly on issues of principle rather than on presenting a large amount of detail. In particular, the author emphasizes the deep theoretical infra-structure that has made lattice studies meaningful. At the same time, he has avoided the use of heavy formalisms as they tend to obscure the basic issues for people trying to approach this subject for the first time. The essential ideas are illustrated with elementary soluble examples not involving complicated mathematics. The following subjects are discussed: three ways of solving the harmonic oscillator problem; latticization; gauge fields on a lattice; QCD observables; how to solve lattice theories. (Auth.)
International Nuclear Information System (INIS)
Creutz, M.
1983-04-01
In the last few years lattice gauge theory has become the primary tool for the study of nonperturbative phenomena in gauge theories. The lattice serves as an ultraviolet cutoff, rendering the theory well defined and amenable to numerical and analytical work. Of course, as with any cutoff, at the end of a calculation one must consider the limit of vanishing lattice spacing in order to draw conclusions on the physical continuum limit theory. The lattice has the advantage over other regulators that it is not tied to the Feynman expansion. This opens the possibility of other approximation schemes than conventional perturbation theory. Thus Wilson used a high temperature expansion to demonstrate confinement in the strong coupling limit. Monte Carlo simulations have dominated the research in lattice gauge theory for the last four years, giving first principle calculations of nonperturbative parameters characterizing the continuum limit. Some of the recent results with lattice calculations are reviewed
Absolute tightness: the chemists hesitate to invest
International Nuclear Information System (INIS)
Anon.
1996-01-01
The safety requirements of industries as nuclear plants and the strengthening of regulations in the field of environment (more particularly those related to volatile organic compounds) have lead the manufacturers to build absolute tightness pumps. But these equipments do not answer all the problems and represent a high investment cost. In consequence, the chemists hesitate to invest. (O.L.)
On Traveling Waves in Lattices: The Case of Riccati Lattices
Dimitrova, Zlatinka
2012-09-01
The method of simplest equation is applied for analysis of a class of lattices described by differential-difference equations that admit traveling-wave solutions constructed on the basis of the solution of the Riccati equation. We denote such lattices as Riccati lattices. We search for Riccati lattices within two classes of lattices: generalized Lotka-Volterra lattices and generalized Holling lattices. We show that from the class of generalized Lotka-Volterra lattices only the Wadati lattice belongs to the class of Riccati lattices. Opposite to this many lattices from the Holling class are Riccati lattices. We construct exact traveling wave solutions on the basis of the solution of Riccati equation for three members of the class of generalized Holling lattices.
Lattice degeneracies of fermions
International Nuclear Information System (INIS)
Raszillier, H.
1983-10-01
We present a detailed description of the minimal degeneracies of geometric (Kaehler) fermions on all the lattices of maximal symmetries in n = 1, ..., 4 dimensions. We also determine the isolated orbits of the maximal symmetry groups, which are related to the minimal numbers of ''naive'' fermions on the reciprocals of these lattices. It turns out that on the self-reciprocal lattices the minimal numbers of naive fermions are equal to the minimal numbers of degrees of freedom of geometric fermions. The description we give relies on the close connection of the maximal lattice symmetry groups with (affine) Weyl groups of root systems of (semi-) simple Lie algebras. (orig.)
International Nuclear Information System (INIS)
Shindler, A.
2007-07-01
I review the theoretical foundations, properties as well as the simulation results obtained so far of a variant of the Wilson lattice QCD formulation: Wilson twisted mass lattice QCD. Emphasis is put on the discretization errors and on the effects of these discretization errors on the phase structure for Wilson-like fermions in the chiral limit. The possibility to use in lattice simulations different lattice actions for sea and valence quarks to ease the renormalization patterns of phenomenologically relevant local operators, is also discussed. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Shindler, A. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC
2007-07-15
I review the theoretical foundations, properties as well as the simulation results obtained so far of a variant of the Wilson lattice QCD formulation: Wilson twisted mass lattice QCD. Emphasis is put on the discretization errors and on the effects of these discretization errors on the phase structure for Wilson-like fermions in the chiral limit. The possibility to use in lattice simulations different lattice actions for sea and valence quarks to ease the renormalization patterns of phenomenologically relevant local operators, is also discussed. (orig.)
Designing lattice structures with maximal nearest-neighbor entanglement
Energy Technology Data Exchange (ETDEWEB)
Navarro-Munoz, J C; Lopez-Sandoval, R [Instituto Potosino de Investigacion CientIfica y Tecnologica, Camino a la presa San Jose 2055, 78216 San Luis Potosi (Mexico); Garcia, M E [Theoretische Physik, FB 18, Universitaet Kassel and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), Heinrich-Plett-Str.40, 34132 Kassel (Germany)
2009-08-07
In this paper, we study the numerical optimization of nearest-neighbor concurrence of bipartite one- and two-dimensional lattices, as well as non-bipartite two-dimensional lattices. These systems are described in the framework of a tight-binding Hamiltonian while the optimization of concurrence was performed using genetic algorithms. Our results show that the concurrence of the optimized lattice structures is considerably higher than that of non-optimized systems. In the case of one-dimensional chains, the concurrence increases dramatically when the system begins to dimerize, i.e., it undergoes a structural phase transition (Peierls distortion). This result is consistent with the idea that entanglement is maximal or shows a singularity near quantum phase transitions. Moreover, the optimization of concurrence in two-dimensional bipartite and non-bipartite lattices is achieved when the structures break into smaller subsystems, which are arranged in geometrically distinguishable configurations.
A triangle voting algorithm based on double feature constraints for star sensors
Fan, Qiaoyun; Zhong, Xuyang
2018-02-01
A novel autonomous star identification algorithm is presented in this study. In the proposed algorithm, each sensor star constructs multi-triangle with its bright neighbor stars and obtains its candidates by triangle voting process, in which the triangle is considered as the basic voting element. In order to accelerate the speed of this algorithm and reduce the required memory for star database, feature extraction is carried out to reduce the dimension of triangles and each triangle is described by its base and height. During the identification period, the voting scheme based on double feature constraints is proposed to implement triangle voting. This scheme guarantees that only the catalog star satisfying two features can vote for the sensor star, which improves the robustness towards false stars. The simulation and real star image test demonstrate that compared with the other two algorithms, the proposed algorithm is more robust towards position noise, magnitude noise and false stars.
Block spins and chirality in Heisenberg model on Kagome and triangular lattices
International Nuclear Information System (INIS)
Subrahmanyam, V.
1994-01-01
The spin-1/2 Heisenberg model (HM) is investigated using a block-spin renormalization approach on Kagome and triangular lattices. In both cases, after coarse graining the triangles on original lattice and truncation of the Hilbert space to the triangular ground state subspace, HM reduces to an effective model on a triangular lattice in terms of the triangular-block degrees of freedom viz. the spin and the chirality quantum numbers. The chirality part of the effective Hamiltonian captures the essential difference between the two lattices. It is seen that simple eigenstates can be constructed for the effective model whose energies serve as upper bounds on the exact ground state energy of HM, and chiral ordered variational states have high energies compared to the other variational states. (author). 12 refs, 2 figs
Colouring the triangles determined by a point set
Directory of Open Access Journals (Sweden)
Ruy Fabila-Monroy
2012-05-01
Full Text Available Let P be a set of n points in general position in the plane. We study the chromatic number of the intersection graph of the open triangles determined by P. It is known that this chromatic number is at least n3/27+O(n2 and, if P is in convex position, the answer is n3/24+O(n2. We prove that for arbitrary P, the chromatic number is at most n3/19.259+O(n2.
Valuation of Non-Life Liabilities from Claims Triangles
Directory of Open Access Journals (Sweden)
Mathias Lindholm
2017-07-01
Full Text Available This paper provides a complete program for the valuation of aggregate non-life insurance liability cash flows based on claims triangle data. The valuation is fully consistent with the principle of valuation by considering the costs associated with a transfer of the liability to a so-called reference undertaking subject to capital requirements throughout the runoff of the liability cash flow. The valuation program includes complete details on parameter estimation, bias correction and conservative estimation of the value of the liability under partial information. The latter is based on a new approach to the estimation of mean squared error of claims reserve prediction.
Triangle identity and free differential algebra of massless higher spins
Energy Technology Data Exchange (ETDEWEB)
Vasiliev, M A [AN SSSR, Moscow. Fizicheskij Inst.
1989-09-25
In terms of Berezins's theory of symbols of operators, the integral formulation is suggested for the free differential algebra which gives rise to consistent equations of motion of interacting massless fields of all spins 0{le}s<{infinity} in the frameworks of gravity. In the first nontrivial order of the expansion in powers of curvatures, Frobenius consistency conditions for higher-spin equations of motion are shown to reduce to the simple geometrical fast that there are two ways for splitting any quadrangle in two triangles. To clarify our construction, we illustrate how it works in the simplest case of pure gravity. (orig.).
Directory of Open Access Journals (Sweden)
Epelbaum E.
2010-04-01
Full Text Available We review recent progress on nuclear lattice simulations using chiral eﬀective ﬁeld theory. We discuss lattice results for dilute neutron matter at next-to-leading order, three-body forces at next-to-next-toleading order, isospin-breaking and Coulomb eﬀects, and the binding energy of light nuclei.
International Nuclear Information System (INIS)
Jersak, J.
1986-01-01
This year has brought a sudden interest in lattice Higgs models. After five years of only modest activity we now have many new results obtained both by analytic and Monte Carlo methods. This talk is a review of the present state of lattice Higgs models with particular emphasis on the recent development
Triangle Universities Nuclear Laboratory annual report - TUNL XXIV, 1 July 1984-31 August 1985
International Nuclear Information System (INIS)
1985-01-01
Research programs of the Triangle Nuclear Laboratory are discussed. These studies are based on reactions induced by polarized beam, protons, deuterons and neutrons. Individual programs are cataloged separately
An evaluation of tight - pitch PWR cores
International Nuclear Information System (INIS)
Correa, F.
1980-01-01
The subtask of a project carried out at MIT (Massachusetts Institute of Technology) for DOE (Department of Energy) as part of their NASAP/INFCE - related effects involving the optimization of PWR lattices in the recycle model is summarized. (E.G.) [pt
Bipolaron assisted Bloch-like oscillations in organic lattices
International Nuclear Information System (INIS)
Ribeiro, Luiz Antonio; Ferreira da Cunha, Wiliam; Magela e Silva, Geraldo
2017-01-01
The transport of a dissociated bipolaron in organic one-dimensional lattices is theoretically investigated in the scope of a tight-binding model that includes electron-lattice interactions and an external electric field. Remarkably, the results point to a physical picture in which the dissociated bipolaron propagates as a combined state of two free-like electrons that coherently perform spatial Bloch oscillations (BO) above a critical field strength. It was also obtained that the BO's trajectory presents a net forward motion in the direction of the applied electric field. The impact of dynamical disorder in the formation of electronic BOs is determined.
Bipolaron assisted Bloch-like oscillations in organic lattices
Ribeiro, Luiz Antonio; Ferreira da Cunha, Wiliam; Magela e Silva, Geraldo
2017-06-01
The transport of a dissociated bipolaron in organic one-dimensional lattices is theoretically investigated in the scope of a tight-binding model that includes electron-lattice interactions and an external electric field. Remarkably, the results point to a physical picture in which the dissociated bipolaron propagates as a combined state of two free-like electrons that coherently perform spatial Bloch oscillations (BO) above a critical field strength. It was also obtained that the BO's trajectory presents a net forward motion in the direction of the applied electric field. The impact of dynamical disorder in the formation of electronic BOs is determined.
Bipolaron assisted Bloch-like oscillations in organic lattices
Energy Technology Data Exchange (ETDEWEB)
Ribeiro, Luiz Antonio, E-mail: ribeirojr@unb.br [International Center for Condensed Matter Physics, University of Brasília, P.O. Box 04531, 70.919-970, Brasília, DF (Brazil); University of Brasília, UnB Faculty of Planaltina, 73.345-010, Planaltina, DF (Brazil); Ferreira da Cunha, Wiliam; Magela e Silva, Geraldo [Institute of Physics, University of Brasília, 70.919-970, Brasília (Brazil)
2017-06-15
The transport of a dissociated bipolaron in organic one-dimensional lattices is theoretically investigated in the scope of a tight-binding model that includes electron-lattice interactions and an external electric field. Remarkably, the results point to a physical picture in which the dissociated bipolaron propagates as a combined state of two free-like electrons that coherently perform spatial Bloch oscillations (BO) above a critical field strength. It was also obtained that the BO's trajectory presents a net forward motion in the direction of the applied electric field. The impact of dynamical disorder in the formation of electronic BOs is determined.
Improving horizontal completions on heterogeneous tight shales
Energy Technology Data Exchange (ETDEWEB)
Suarez-Rivera, Roberto; Deenadayalu, Chaitanya; Chertov, Maxim; Novalo Hartanto, Ricardo; Gathogo, Patrick [Schlumberger (United States); Kunjir, Rahul [University of Utah (United States)
2011-07-01
Evaluation of the two formation characteristics conducive to economic well production is important when tight shale formation characterization and completion design are being considered. This paper presents the basic understanding required to improve the efficiency of horizontal completions in oil and gas producing shales. Guidelines are defined for effective perforation and fracturing to improve the efficiency and sustainability of horizontal completions using extensive laboratory characterization of mechanical properties on core, core/log integration and continuous mapping of these properties by logging-while-drilling (LWD) methods. The objective is to improve completion design efficiency. This is accomplished by suitable selection of perforation intervals based on an understanding of the relevant physical processes and rock characterization. Conditions at two reservoir regions, the near-wellbore and the far-wellbore, are outlined and are essential to completion design. From the study, it can be concluded that tight shales are strongly anisotropic and cannot be approximated using isotropic models.
Tight fitting garter springs-MODAR
Energy Technology Data Exchange (ETDEWEB)
Kazimer, D. [Bruce Power, Tiverton, Ontario (Canada)
2011-07-01
Annulus spacers are used in CANDU reactors to maintain the annular gap between two tubes - an inner pressure tube (PT) and the outer calandria tube (CT). Typically four annulus spacers are used in one fuel channel assembly, each at a specified axial position. Bruce Unit 8 and many other CANDU units were constructed with tight-fitting garter springs (TFGS). The TFGS were not designed to be detected or relocated by the conventional tool, Spacer Location And Repositioning (SLAR) processes. Due to non-optimal 'As Left' construction locations for the Bruce Unit 8 TFGS, PT/CT contact has been predicted to occur well prior to its End of Life (EOL). Bruce Power entered a Project with AECL-CRL to design, manufacture and test and implement a new tooling system that would detect and reposition tight fitting annulus spacers. (author)
Surface Passivation in Empirical Tight Binding
He, Yu; Tan, Yaohua; Jiang, Zhengping; Povolotskyi, Michael; Klimeck, Gerhard; Kubis, Tillmann
2015-01-01
Empirical Tight Binding (TB) methods are widely used in atomistic device simulations. Existing TB methods to passivate dangling bonds fall into two categories: 1) Method that explicitly includes passivation atoms is limited to passivation with atoms and small molecules only. 2) Method that implicitly incorporates passivation does not distinguish passivation atom types. This work introduces an implicit passivation method that is applicable to any passivation scenario with appropriate parameter...
Equiangular tight frames and unistochastic matrices
Czech Academy of Sciences Publication Activity Database
Goyeneche, D.; Turek, Ondřej
2017-01-01
Roč. 50, č. 24 (2017), č. článku 245304. ISSN 1751-8113 R&D Projects: GA ČR GA17-01706S Institutional support: RVO:61389005 Keywords : equiangular tight frames * unistochastic matrices * SIC POVM Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 1.857, year: 2016
The Surgical Anatomy of the Lumbosacroiliac Triangle: A Cadaveric Study.
Zoccali, Carmine; Skoch, Jesse; Patel, Apar S; Walter, Christina M; Avila, Mauricio J; Martirosyan, Nikolay L; Demitri, Silvio; Baaj, Ali A
2016-04-01
The anatomic area delineated medially by the lateral part of the L4-L5 vertebral bodies, distally by the anterior-superior surface of the sacral wing, and laterally by an imaginary line joining the base of the L4 transverse process to the proximal part of the sacroiliac joint, is of particular interest to spine surgeons. We are referring to this area as the lumbo-sacro-iliac triangle (LSIT). Knowledge of LSIT anatomy is necessary during approaches for L5 vertebral and sacral fractures, sacral and iliac tumors, and extraforaminal decompression of the L5 nerve roots. We performed an anatomic dissection of the LSIT in 3 embalmed cadavers (6 triangles), using an anterior and posterior approach. We identified 3 key tissue planes: the neurological plexus plane, constituted by L4 and L5 nerve roots; an intermediate level constituted by the ileosacral tunnel; and posteriorly, by the lumbosacral ligament, and the posterior muscular plane. Improving anatomic knowledge of the LSIT may help surgeons decrease the risk of possible complications. When LSIT pathology is present, a lateral approach corresponding to the tip of the L4 transverse process, medially, is suggested to decrease the risk of vessel and nerve root damage. Copyright © 2016 Elsevier Inc. All rights reserved.
STRATEGIC PLACE TRIANGLE PENGEMBANGAN POTENSI KAWASAN PARIWISATA BOJONEGERO
Directory of Open Access Journals (Sweden)
Muchammad Nurif
2015-06-01
Full Text Available Kabupaten Bojonegoro ditetapkan sebagai salah satu Daerah Tujuan Wisata (DTW di Jawa Timur karena memiliki potensi obyek wisata alam dan budaya yang telah mendapatkan perhatian wisatawan nusantara pada umumnya. Dalam kebijakan pengembangan yang tertuang dalam Rencana Induk Pengembangan Pariwisata (RIPP Jawa Timur 1999-2015 Kabupaten Bojonegoro meskipun bukan sebagai gerbang utama namun memiliki peran strategis untuk mendorong pertumbuhan kawasan di sekitarnya. Dalam penelitian, peneliti melakukan pemetakan perubahan lingkungan eksternal, pemetakan pesaing dan pelanggan, analisis internal, dan analisis TOWS. Selanjutnya akan dirumuskan Strategic Place Triangle. Yang dimaksud dengan Strategic Place Triangle adalah suatu pendekatan strategi pemasaran wilayah yang mencakup tiga hal kunci, yaitu (1 Strategi yang mencakup Segmentasi-Targeting-Positioning, (2 Taktik yang mencakup Diferensiasi-Marketing Mix-Selling, (3 Value yang mencakup Brand-Servis-Proses. Analisis pemetaan terhadap lingkungan eksternal dan internal dengan menggunakan pendekatan Strategi Pemasaran Wilayah (Marketing Places tersebut akan menghasilkan Positioning, Diferensiasi, dan Brand, bagi potensi kawasan pariwisata Bojonegoro. Positioning- nya adalah ibarat Bali bagi Jawa Timur dengan kekhasan tetap memegang nilai-nilai religi dan kultur lokal setempat. Diferensiasi-nya adalah one-stop-shopping services, pesona wisata yang tak berakhir, cantik alami, penduduknya yang santun, ramah dan mempesona. Brand-nya adalah Pesona Wisata Bojonegoro.
Electronic confining effects in Sierpiński triangle fractals
Wang, Hao; Zhang, Xue; Jiang, Zhuoling; Wang, Yongfeng; Hou, Shimin
2018-03-01
Electron confinement in fractal Sierpiński triangles (STs) on Ag(111) is investigated using scanning tunneling spectroscopy and theoretically simulated by employing an improved two-dimensional (2D) multiple scattering theory in which the energy-dependent phase shifts are explicitly calculated from the electrostatic potentials of the molecular building block of STs. Well-defined bound surface states are observed in three kinds of triangular cavities with their sides changing at a scale factor of 2. The decrease in length of the cavities results in an upshift of the resonances that deviates from an expected inverse quadratic dependence on the cavity length due to the less efficient confinement of smaller triangular cavities. Differential conductance maps at some specific biases present a series of alternative bright and dark rounded triangles preserving the symmetry of the boundary. Our improved 2D multiple scattering model reproduces the characteristics of the standing wave patterns and all features in the differential conductance spectra measured in experiments, illustrating that the elastic loss boundary scattering dominates the resonance broadening in these ST quantum corrals. Moreover, the self-similar structure of STs, that a larger central cavity is surrounded by three smaller ones with a half side length, gives rise to interactions of surface states confined in neighboring cavities, which are helpful for the suppression of the linewidth in differential conductance spectra.
Species richness accelerates marine ecosystem restoration in the Coral Triangle.
Williams, Susan L; Ambo-Rappe, Rohani; Sur, Christine; Abbott, Jessica M; Limbong, Steven R
2017-11-07
Ecosystem restoration aims to restore biodiversity and valuable functions that have been degraded or lost. The Coral Triangle is a hotspot for marine biodiversity held in its coral reefs, seagrass meadows, and mangrove forests, all of which are in global decline. These coastal ecosystems support valuable fisheries and endangered species, protect shorelines, and are significant carbon stores, functions that have been degraded by coastal development, destructive fishing practices, and climate change. Ecosystem restoration is required to mitigate these damages and losses, but its practice is in its infancy in the region. Here we demonstrate that species diversity can set the trajectory of restoration. In a seagrass restoration experiment in the heart of the Coral Triangle (Sulawesi, Indonesia), plant survival and coverage increased with the number of species transplanted. Our results highlight the positive role biodiversity can play in ecosystem restoration and call for revision of the common restoration practice of establishing a single target species, particularly in regions having high biodiversity. Coastal ecosystems affect human well-being in many important ways, and restoration will become ever more important as conservation efforts cannot keep up with their loss. Published under the PNAS license.
[Cysts in the posterior triangle of the neck in adults].
Brea-Álvarez, Beatriz; Roldán-Hidalgo, Amaya
2015-01-01
Cystic lesions of the posterior triangle are a pathologic entity whose diagnosis is made in the first two years of life. Its presentation in adulthood is an incidental finding and the differential diagnosis includes cystic lymphangioma, lymphatic metastasis of thyroid cancer and branchial cyst. Often with the finding of a cervical lump, FNA is made before diagnostic imaging is performed, however, this procedure is not always advisable. We reviewed the cases of patients who came last year to our department with a cystic mass in this location and correlating the imaging findings with pathologic specimen. We show characteristic findings of these lesions in order to make an early diagnosis and thus to get the approach and treatment appropriate of adult patients with a cystic lesion in the posterior cervical triangle. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.
Triangle bipolar pulse shaping and pileup correction based on DSP
International Nuclear Information System (INIS)
Esmaeili-sani, Vahid; Moussavi-zarandi, Ali; Akbar-ashrafi, Nafiseh; Boghrati, Behzad
2011-01-01
Programmable Digital Signal Processing (DSP) microprocessors are capable of doing complex discrete signal processing algorithms with clock rates above 50 MHz. This combined with their low expense, ease of use and selected dedicated hardware make them an ideal option for spectrometer data acquisition systems. For this generation of spectrometers, functions that are typically performed in dedicated circuits, or offline, are being migrated to the field programmable gate array (FPGA). This will not only reduce the electronics, but the features of modern FPGAs can be utilized to add considerable signal processing power to produce higher resolution spectra. In this paper we report on an all-digital triangle bipolar pulse shaping and pileup correction algorithm that is being developed for the DSP. The pileup mitigation algorithm will allow the spectrometers to run at higher count rates or with multiple sources without imposing large data losses due to the overlapping of scintillation signals. This correction technique utilizes a very narrow bipolar triangle digital pulse shaping algorithm to extract energy information for most pileup events.
Triangle bipolar pulse shaping and pileup correction based on DSP
Energy Technology Data Exchange (ETDEWEB)
Esmaeili-sani, Vahid, E-mail: vaheed_esmaeely80@yahoo.com [Department of Nuclear Engineering and Physics, Amirkabir University of Technology, P.O. Box 4155-4494, Tehran (Iran, Islamic Republic of); Moussavi-zarandi, Ali; Akbar-ashrafi, Nafiseh; Boghrati, Behzad [Department of Nuclear Engineering and Physics, Amirkabir University of Technology, P.O. Box 4155-4494, Tehran (Iran, Islamic Republic of)
2011-02-11
Programmable Digital Signal Processing (DSP) microprocessors are capable of doing complex discrete signal processing algorithms with clock rates above 50 MHz. This combined with their low expense, ease of use and selected dedicated hardware make them an ideal option for spectrometer data acquisition systems. For this generation of spectrometers, functions that are typically performed in dedicated circuits, or offline, are being migrated to the field programmable gate array (FPGA). This will not only reduce the electronics, but the features of modern FPGAs can be utilized to add considerable signal processing power to produce higher resolution spectra. In this paper we report on an all-digital triangle bipolar pulse shaping and pileup correction algorithm that is being developed for the DSP. The pileup mitigation algorithm will allow the spectrometers to run at higher count rates or with multiple sources without imposing large data losses due to the overlapping of scintillation signals. This correction technique utilizes a very narrow bipolar triangle digital pulse shaping algorithm to extract energy information for most pileup events.
On singularities of lattice varieties
Mukherjee, Himadri
2013-01-01
Toric varieties associated with distributive lattices arise as a fibre of a flat degeneration of a Schubert variety in a minuscule. The singular locus of these varieties has been studied by various authors. In this article we prove that the number of diamonds incident on a lattice point $\\a$ in a product of chain lattices is more than or equal to the codimension of the lattice. Using this we also show that the lattice varieties associated with product of chain lattices is smooth.
Anderson localization in bipartite lattices
International Nuclear Information System (INIS)
Fabrizio, Michele; Castellani, Claudio
2000-01-01
We study the localization properties of a disordered tight-binding Hamiltonian on a generic bipartite lattice close to the band center. By means of a fermionic replica trick method, we derive the effective non-linear σ-model describing the diffusive modes, which we analyse by using the Wilson-Polyakov renormalization group. In addition to the standard parameters which define the non-linear σ-model, namely, the conductance and the external frequency, a new parameter enters, which may be related to the fluctuations of the staggered density of states. We find that, when both the regular hopping and the disorder only couple one sublattice to the other, the quantum corrections to the Kubo conductivity vanish at the band center, thus implying the existence of delocalized states. In two dimensions, the RG equations predict that the conductance flows to a finite value, while both the density of states and the staggered density of states fluctuations diverge. In three dimensions, we find that, sufficiently close to the band center, all states are extended, independently of the disorder strength. We also discuss the role of various symmetry breaking terms, as a regular hopping between same sublattices, or an on-site disorder
Anderson localization in bipartite lattices
International Nuclear Information System (INIS)
Fabrizio, M.; Castellani, C.
2000-04-01
We study the localization properties of a disordered tight-binding Hamiltonian on a generic bipartite lattice close to the band center. By means of a fermionic replica trick method, we derive the effective non-linear σ-model describing the diffusive modes, which we analyse by using the Wilson-Polyakov renormalization group. In addition to the standard parameters which define the non-linear σ-model, namely the conductance and the external frequency, a new parameter enters, which may be related to the fluctuations of the staggered density of states. We find that, when both the regular hopping and the disorder only couple one sublattice to the other, the quantum corrections to the Kubo conductivity vanish at the band center, thus implying the existence of delocalized states. In two dimensions, the RG equations predict that the conductance flows to a finite value, while both the density of states and the staggered density of states fluctuations diverge. In three dimensions, we find that, sufficiently close to the band center, all states are extended, independently of the disorder strength. We also discuss the role of various symmetry breaking terms, as a regular hopping between same sublattices, or an on-site disorder. (author)
Fujiwara, Takeo; Nishino, Shinya; Yamamoto, Susumu; Suzuki, Takashi; Ikeda, Minoru; Ohtani, Yasuaki
2018-06-01
A novel tight-binding method is developed, based on the extended Hückel approximation and charge self-consistency, with referring the band structure and the total energy of the local density approximation of the density functional theory. The parameters are so adjusted by computer that the result reproduces the band structure and the total energy, and the algorithm for determining parameters is established. The set of determined parameters is applicable to a variety of crystalline compounds and change of lattice constants, and, in other words, it is transferable. Examples are demonstrated for Si crystals of several crystalline structures varying lattice constants. Since the set of parameters is transferable, the present tight-binding method may be applicable also to molecular dynamics simulations of large-scale systems and long-time dynamical processes.
Tight-binding calculation of Ti-Rh--type phase diagram
International Nuclear Information System (INIS)
Sluiter, M.; Turchi, P.; Fu Zezhong; de Fontaine, D.
1988-01-01
Tight-binding electronic band-structure calculations were combined with a free-energy expression from a statistical mechanical method called the cluster-variation method. The effective pair interactions used in the cluster-variation calculation were evaluated by the generalized perturbation method. Only d orbitals were included and the numbers of d electrons per atom were taken to be three for the pure A element and eight for the pure B. A phase diagram was constructed incorporating, for the first time, both fcc and bcc lattices and their simple-ordered superstructures. The calculated diagram agreed reasonably well with those determined empirically for Ti-Rh or Ti-Ir
Pugh, Greg L.
2014-01-01
The pink triangle exercise is an example of an experiential learning exercise that creates cognitive dissonance and deep learning of unrealized internalized biases among social work students. Students wear a button with a pink triangle on it for 1 day and write a reflection paper. The exercise increases self-awareness, cultural competence, and the…
The number of colorings of planar graphs with no separating triangles
DEFF Research Database (Denmark)
Thomassen, Carsten
2017-01-01
A classical result of Birkhoff and Lewis implies that every planar graph with . n vertices has at least . 152n-1 distinct 5-vertex-colorings. Equality holds for planar triangulations with . n-4 separating triangles. We show that, if a planar graph has no separating triangle, then it has at least ...
75 FR 61788 - Triangle Capital Corporation, et al.; Notice of Application
2010-10-06
... to the issuers of such securities. 2. TMF, a North Carolina limited liability limited partnership, is... same investment objectives and strategies as Triangle. Triangle owns a 99.9% limited partnership... persons who are interested persons of TMF. 3. SBIC II, a Delaware limited partnership, is an SBIC licensed...
International Nuclear Information System (INIS)
Mackenzie, Paul
1989-01-01
The forty-year dream of understanding the properties of the strongly interacting particles from first principles is now approaching reality. Quantum chromodynamics (QCD - the field theory of the quark and gluon constituents of strongly interacting particles) was initially handicapped by the severe limitations of the conventional (perturbation) approach in this picture, but Ken Wilson's inventions of lattice gauge theory and renormalization group methods opened new doors, making calculations of masses and other particle properties possible. Lattice gauge theory became a major industry around 1980, when Monte Carlo methods were introduced, and the first prototype calculations yielded qualitatively reasonable results. The promising developments over the past year were highlighted at the 1988 Symposium on Lattice Field Theory - Lattice 88 - held at Fermilab
DEFF Research Database (Denmark)
Risager, Morten S.; Södergren, Carl Anders
2017-01-01
It is well known that the angles in a lattice acting on hyperbolic n -space become equidistributed. In this paper we determine a formula for the pair correlation density for angles in such hyperbolic lattices. Using this formula we determine, among other things, the asymptotic behavior of the den......It is well known that the angles in a lattice acting on hyperbolic n -space become equidistributed. In this paper we determine a formula for the pair correlation density for angles in such hyperbolic lattices. Using this formula we determine, among other things, the asymptotic behavior...... of the density function in both the small and large variable limits. This extends earlier results by Boca, Pasol, Popa and Zaharescu and Kelmer and Kontorovich in dimension 2 to general dimension n . Our proofs use the decay of matrix coefficients together with a number of careful estimates, and lead...
International Nuclear Information System (INIS)
Kulikowska, T.
1999-01-01
The present lecture has a main goal to show how the transport lattice calculations are realised in a standard computer code. This is illustrated on the example of the WIMSD code, belonging to the most popular tools for reactor calculations. Most of the approaches discussed here can be easily modified to any other lattice code. The description of the code assumes the basic knowledge of reactor lattice, on the level given in the lecture on 'Reactor lattice transport calculations'. For more advanced explanation of the WIMSD code the reader is directed to the detailed descriptions of the code cited in References. The discussion of the methods and models included in the code is followed by the generally used homogenisation procedure and several numerical examples of discrepancies in calculated multiplication factors based on different sources of library data. (author)
Energy Technology Data Exchange (ETDEWEB)
Mackenzie, Paul
1989-03-15
The forty-year dream of understanding the properties of the strongly interacting particles from first principles is now approaching reality. Quantum chromodynamics (QCD - the field theory of the quark and gluon constituents of strongly interacting particles) was initially handicapped by the severe limitations of the conventional (perturbation) approach in this picture, but Ken Wilson's inventions of lattice gauge theory and renormalization group methods opened new doors, making calculations of masses and other particle properties possible. Lattice gauge theory became a major industry around 1980, when Monte Carlo methods were introduced, and the first prototype calculations yielded qualitatively reasonable results. The promising developments over the past year were highlighted at the 1988 Symposium on Lattice Field Theory - Lattice 88 - held at Fermilab.
International Nuclear Information System (INIS)
Christ, Norman H
2000-01-01
The architecture and capabilities of the computers currently in use for large-scale lattice QCD calculations are described and compared. Based on this present experience, possible future directions are discussed
International Nuclear Information System (INIS)
Kulikowska, T.
2001-01-01
The description of reactor lattice codes is carried out on the example of the WIMSD-5B code. The WIMS code in its various version is the most recognised lattice code. It is used in all parts of the world for calculations of research and power reactors. The version WIMSD-5B is distributed free of charge by NEA Data Bank. The description of its main features given in the present lecture follows the aspects defined previously for lattice calculations in the lecture on Reactor Lattice Transport Calculations. The spatial models are described, and the approach to the energy treatment is given. Finally the specific algorithm applied in fuel depletion calculations is outlined. (author)
Tight Reference Frame–Independent Quantum Teleportation
Directory of Open Access Journals (Sweden)
Dominic Verdon
2017-01-01
Full Text Available We give a tight scheme for teleporting a quantum state between two parties whose reference frames are misaligned by an action of a finite symmetry group. Unlike previously proposed schemes, ours requires no additional tokens or data to be passed between the participants; the same amount of classical information is transferred as for ordinary quantum teleportation, and the Hilbert space of the entangled resource is of the same size. In the terminology of Peres and Scudo, our protocol relies on classical communication of unspeakable information.
Tightly sealed facility of excellent in durability
International Nuclear Information System (INIS)
Shirano, Kenji; Chatani, Michio; Ebe, Shinji; Shimizu, Masatoshi; Seguchi, Tadao; Fukushima, Susumu; Hirata, Masaru; Shiosawa, Ken-ichi.
1992-01-01
It is found that a cross linked methacryl resin using an appropriate amount of a cross linking monomer also has a useful characteristic of an excellent chemical resistance and excellent γ-ray resistance. Then in the present invention, a cross linked methacryl resin molding product comprising 60 to 98 % by weight of methyl methacrylate units and 2 to 40 % by weight of cross linking monomer units is used as a material for transparent partition walls. A tightly sealed facility having the transparent partition wall materials of excellent radiation resistance in addition to acid resistance can be attained. (T.M.)
International Nuclear Information System (INIS)
Petronzio, R.
1992-01-01
Lattice gauge theories are about fifteen years old and I will report on the present status of the field without making the elementary introduction that can be found in the proceedings of the last two conferences. The talk covers briefly the following subjects: the determination of α s , the status of spectroscopy, heavy quark physics and in particular the calculation of their hadronic weak matrix elements, high temperature QCD, non perturbative Higgs bounds, chiral theories on the lattice and induced theories
Kiefel, Martin; Jampani, Varun; Gehler, Peter V.
2014-01-01
This paper presents a convolutional layer that is able to process sparse input features. As an example, for image recognition problems this allows an efficient filtering of signals that do not lie on a dense grid (like pixel position), but of more general features (such as color values). The presented algorithm makes use of the permutohedral lattice data structure. The permutohedral lattice was introduced to efficiently implement a bilateral filter, a commonly used image processing operation....
Castle, Toen; Sussman, Daniel M; Tanis, Michael; Kamien, Randall D
2016-09-01
Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes.
Construction of optimal 3-node plate bending triangles by templates
Felippa, C. A.; Militello, C.
A finite element template is a parametrized algebraic form that reduces to specific finite elements by setting numerical values to the free parameters. The present study concerns Kirchhoff Plate-Bending Triangles (KPT) with 3 nodes and 9 degrees of freedom. A 37-parameter template is constructed using the Assumed Natural Deviatoric Strain (ANDES). Specialization of this template includes well known elements such as DKT and HCT. The question addressed here is: can these parameters be selected to produce high performance elements? The study is carried out by staged application of constraints on the free parameters. The first stage produces element families satisfying invariance and aspect ratio insensitivity conditions. Application of energy balance constraints produces specific elements. The performance of such elements in benchmark tests is presently under study.
Climate, bleaching and connectivity in the Coral Triangle.
Curchitser, E. N.; Kleypas, J. A.; Castruccio, F. S.; Drenkard, E.; Thompson, D. M.; Pinsky, M. L.
2016-12-01
The Coral Triangle (CT) is the apex of marine biodiversity and supports the livelihoods of millions of people. It is also one of the most threatened of all reef regions in the world. We present results from a series of high-resolution, numerical ocean models designed to address physical and ecological questions relevant to the region's coral communities. The hierarchy of models was designed to optimize the model performance in addressing questions ranging from the role of internal tides in larval connectivity to distinguishing the role of interannual variability from decadal trends in thermal stress leading to mass bleaching events. In this presentation we will show how combining ocean circulation with models of larval dispersal leads to new insights into the interplay of physics and ecology in this complex oceanographic region, which can ultimately be used to inform conservation efforts.
[Patient - doctor relationship from perspective of the Karpman drama triangle].
Samborska-Sablik, Anna; Sablik, Zbigniew
2016-11-25
Patients' confidence in doctors has been decreased for last years despite successes of Polish medicine. It seems to be related to particular conditions of patient - doctor relationship and patient's negative emotions may frequently burden it from the beginning. They may allow an interpersonal game, the Drama Triangle, to appear in the relationship. 3 persons are typically involved in the game: a victim, a persecutor and a rescuer. All of them neither feel guilty about the situation nor their activities are aimed at solving the crucial problem. It maintains continuation of the game. Both patient and doctor are capable to attend the game as any of the person mentioned above. Authors of the article think frameworks of organization of the health care system should permit doctors not only to tackle main disease but also to devote time individually tailored to patient's emotional problems. © 2016 MEDPRESS.
9th International Workshop on the CKM Unitarity Triangle
CKM2016
2016-01-01
The 9th International Workshop on the CKM Unitarity Triangle (CKM 2016) will be held during November 28 to December 3, 2016 at the Tata Institute of Fundamental Research in Mumbai, India. The CKM series is a well-established international meeting in the field of quark-flavour physics that brings both experimenters and theorists on a common platform. On the experimental front, we bridge borders between neutron, kaon, charm and beauty hadron, and top quark physics. The theory program tries to cover a wide range of approaches. We shall discuss how this marriage of the two can indirectly probe physics beyond the standard model, taking into account the interplay with high-pT collider searches.
Lattice regularized chiral perturbation theory
International Nuclear Information System (INIS)
Borasoy, Bugra; Lewis, Randy; Ouimet, Pierre-Philippe A.
2004-01-01
Chiral perturbation theory can be defined and regularized on a spacetime lattice. A few motivations are discussed here, and an explicit lattice Lagrangian is reviewed. A particular aspect of the connection between lattice chiral perturbation theory and lattice QCD is explored through a study of the Wess-Zumino-Witten term
Comparing MapReduce and Pipeline Implementations for Counting Triangles
Directory of Open Access Journals (Sweden)
Edelmira Pasarella
2017-01-01
Full Text Available A common method to define a parallel solution for a computational problem consists in finding a way to use the Divide and Conquer paradigm in order to have processors acting on its own data and scheduled in a parallel fashion. MapReduce is a programming model that follows this paradigm, and allows for the definition of efficient solutions by both decomposing a problem into steps on subsets of the input data and combining the results of each step to produce final results. Albeit used for the implementation of a wide variety of computational problems, MapReduce performance can be negatively affected whenever the replication factor grows or the size of the input is larger than the resources available at each processor. In this paper we show an alternative approach to implement the Divide and Conquer paradigm, named dynamic pipeline. The main features of dynamic pipelines are illustrated on a parallel implementation of the well-known problem of counting triangles in a graph. This problem is especially interesting either when the input graph does not fit in memory or is dynamically generated. To evaluate the properties of pipeline, a dynamic pipeline of processes and an ad-hoc version of MapReduce are implemented in the language Go, exploiting its ability to deal with channels and spawned processes. An empirical evaluation is conducted on graphs of different topologies, sizes, and densities. Observed results suggest that dynamic pipelines allows for an efficient implementation of the problem of counting triangles in a graph, particularly, in dense and large graphs, drastically reducing the execution time with respect to the MapReduce implementation.
Food supply depends on seagrass meadows in the coral triangle
International Nuclear Information System (INIS)
Unsworth, Richard K F; Hinder, Stephanie L; Bodger, Owen G; Cullen-Unsworth, Leanne C
2014-01-01
The tropical seascape provides food and livelihoods to hundreds of millions of people, but the support of key habitats to this supply remains ill appreciated. For fisheries and conservation management actions to help promote resilient ecosystems, sustainable livelihoods, and food supply, knowledge is required about the habitats that help support fisheries productivity and the consequences of this for food security. This paper provides an interdisciplinary case study from the coral triangle of how seagrass meadows provide support for fisheries and local food security. We apply a triangulated approach that utilizes ecological, fisheries and market data combined with over 250 household interviews. Our research demonstrates that seagrass associated fauna in a coral triangle marine protected area support local food supply contributing at least 50% of the fish based food. This formed between 54% and 99% of daily protein intake in the area. Fishery catch was found to significantly vary with respect to village (p < 0.01) with habitat configuration a probable driver. Juvenile fish comprised 26% of the fishery catch and gear type significantly influenced this proportion (<0.05). Limited sustainability of fishery practices (high juvenile catch and a 51% decline in CPUE for the biggest fishery) and poor habitat management mean the security of this food supply has the potential to be undermined in the long-term. Findings of this study have implications for the management and assessment of fisheries throughout the tropical seascape. Our study provides an exemplar for why natural resource management should move beyond biodiversity and consider how conservation and local food security are interlinked processes that are not mutually exclusive. Seagrass meadows are under sustained threat worldwide, this study provides evidence of the need to conserve these not just to protect biodiversity but to protect food security. (letter)
Sound waves and dynamics of superfluid Fermi gases in optical lattices
International Nuclear Information System (INIS)
Zhang Aixia; Xue Jukui
2009-01-01
The sound waves, the stability of Bloch waves, the Bloch oscillation, and the self-trapping phenomenon in interacting two-component Fermi gases throughout the BEC-BCS crossover in one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) optical lattices are discussed in detail. Within the hydrodynamical theory and by using the perturbative and tight-binding approximation, sound speed in both weak and tight 1D, 2D, 3D optical lattices, and the criteria for occurrences of instability of Bloch waves and self-trapping of Fermi gases along the whole BEC-BCS crossover in tight 1D, 2D, 3D optical lattices are obtained analytically. The results show that the sound speed, the criteria for occurrences of instability of Bloch waves and self-trapping, and the destruction of Bloch oscillation are modified dramatically by the lattice parameters (lattice dimension and lattice strength), the atom density or atom number, and the atom interaction.
International Nuclear Information System (INIS)
Monir, C.
1991-02-01
A two-dimensional procedure, VANTACY-II, describing the turbulent velocity and temperature fields for single phase flow in tight lattices is presented and validated. The flow is assumed to be steady, incrompressible and hydraulic and thermal fully developed. First, the state of art of turbulent momentum and heat transport in tight lattices is documented. It is shown that there is a necessity for experimental investigations in the field of turbulent heat transport. The presented new procedure is based on the turbulence model VELASCO-TUBS by NEELEN. The numerical solution of the balance equations is done by the finite element method code VANTACY by KAISER. The validation of the new procedure VANTACY-II is done by comparing the numerically calculated data for the velocity and temperature fields and for natural mixing with the experimental data of SEALE. The comparison shows a good agreement of experimental and numerically computed data. The observed differences can be mainly attributed to the model of the turbulent PRANDTL number used in the new procedure. (orig.) [de
Owerre, S A
2017-09-27
In the conventional ferromagnetic systems, topological magnon bands and thermal Hall effect are due to the Dzyaloshinskii-Moriya interaction (DMI). In principle, however, the DMI is either negligible or it is not allowed by symmetry in some quantum magnets. Therefore, we expect that topological magnon features will not be present in those systems. In addition, quantum magnets on the triangular-lattice are not expected to possess topological features as the DMI or spin-chirality cancels out due to equal and opposite contributions from adjacent triangles. Here, however, we predict that the isomorphic frustrated honeycomb-lattice and bilayer triangular-lattice antiferromagnetic system will exhibit topological magnon bands and topological thermal Hall effect in the absence of an intrinsic DMI. These unconventional topological magnon features are present as a result of magnetic-field-induced non-coplanar spin configurations with nonzero scalar spin chirality. The relevance of the results to realistic bilayer triangular antiferromagnetic materials are discussed.
Equiangular tight frames and unistochastic matrices
International Nuclear Information System (INIS)
Goyeneche, Dardo; Turek, Ondřej
2017-01-01
We demonstrate that a complex equiangular tight frame composed of N vectors in dimension d , denoted ETF ( d , N ), exists if and only if a certain bistochastic matrix, univocally determined by N and d , belongs to a special class of unistochastic matrices. This connection allows us to find new complex ETFs in infinitely many dimensions and to derive a method to introduce non-trivial free parameters in ETFs. We present an explicit six-parametric family of complex ETF(6,16), which defines a family of symmetric POVMs. Minimal and maximal possible average entanglement of the vectors within this qubit–qutrit family are described. Furthermore, we propose an efficient numerical procedure to compute the unitary matrix underlying a unistochastic matrix, which we apply to find all existing classes of complex ETFs containing up to 20 vectors. (paper)
Surface Passivation in Empirical Tight Binding
He, Yu; Tan, Yaohua; Jiang, Zhengping; Povolotskyi, Michael; Klimeck, Gerhard; Kubis, Tillmann
2016-03-01
Empirical Tight Binding (TB) methods are widely used in atomistic device simulations. Existing TB methods to passivate dangling bonds fall into two categories: 1) Method that explicitly includes passivation atoms is limited to passivation with atoms and small molecules only. 2) Method that implicitly incorporates passivation does not distinguish passivation atom types. This work introduces an implicit passivation method that is applicable to any passivation scenario with appropriate parameters. This method is applied to a Si quantum well and a Si ultra-thin body transistor oxidized with SiO2 in several oxidation configurations. Comparison with ab-initio results and experiments verifies the presented method. Oxidation configurations that severely hamper the transistor performance are identified. It is also shown that the commonly used implicit H atom passivation overestimates the transistor performance.
Naturally fractured tight gas reservoir detection optimization
Energy Technology Data Exchange (ETDEWEB)
NONE
1999-06-01
Building upon the partitioning of the Greater Green River Basin (GGRB) that was conducted last quarter, the goal of the work this quarter has been to conclude evaluation of the Stratos well and the prototypical Green River Deep partition, and perform the fill resource evaluation of the Upper Cretaceous tight gas play, with the goal of defining target areas of enhanced natural fracturing. The work plan for the quarter of November 1-December 31, 1998 comprised four tasks: (1) Evaluation of the Green River Deep partition and the Stratos well and examination of potential opportunity for expanding the use of E and P technology to low permeability, naturally fractured gas reservoirs, (2) Gas field studies, and (3) Resource analysis of the balance of the partitions.
Random walks and polygons in tight confinement
International Nuclear Information System (INIS)
Diao, Y; Ernst, C; Ziegler, U
2014-01-01
We discuss the effect of confinement on the topology and geometry of tightly confined random walks and polygons. Here the walks and polygons are confined in a sphere of radius R ≥ 1/2 and the polygons are equilateral with n edges of unit length. We illustrate numerically that for a fixed length of random polygons the knotting probability increases to one as the radius decreases to 1/2. We also demonstrate that for random polygons (walks) the curvature increases to πn (π(n – 1)) as the radius approaches 1/2 and that the torsion decreases to ≈ πn/3 (≈ π(n – 1)/3). In addition we show the effect of length and confinement on the average crossing number of a random polygon
Tight gas sand tax credit yields opportunities
International Nuclear Information System (INIS)
Lewis, F.W.; Osburn, A.S.
1991-01-01
The U.S. Internal Revenue Service on Apr. 1, 1991, released the inflation adjustments used in the calculations of Non-Conventional Fuel Tax Credits for 1990. The inflation adjustment, 1.6730, when applied to the base price of $3/bbl of oil equivalent, adjusts the tax credit to $5.019/bbl for oil and 86.53 cents/MMBTU for gas. The conversion factor for equivalent fuels is 5.8 MMBTU/bbl. Unfortunately, the tax credit for tight formation gas continues to be unadjusted for inflation and remains 52 cents/MMBTU. As many producers are aware, the Omnibus Budget Reconciliation Act of 1990 expanded the dates of eligibility and the usage for-Non-Conventional Fuel Tax Credits. Among other provisions, eligible wells may be placed in service until Jan. 1, 1992, and once in place may utilize the credit for production through Dec. 31, 2002. Both dates are 2 year extensions from previous regulations
Triangle islands and cavities on the surface of evaporated Cu(In, Ga)Se2 absorber layer
International Nuclear Information System (INIS)
Han Anjun; Zhang Yi; Liu Wei; Li Boyan; Sun Yun
2012-01-01
Highlights: ► Lots of uncommon triangle islands and cavities are found on (1 1 2) planes terminated by Se atoms of evaporated Cu(In, Ga)Se 2 thin films. ► Se ad-dimer as a nucleus, Cu atom diffusion from Cu(In, Ga)Se 2 grains brings the epitaxial triangle island. ► The triangle islands grow with a two-dimensional layered mode. ► The triangle cavities are formed due to the insufficient coalescence of triangle islands. ► The performance of solar cell without triangle islands is improved. - Abstract: Cu(In, Ga)Se 2 (CIGS) thin films are co-evaporated at a constant substrate temperature of 500 °C on the Mo/soda lime glass substrates. The structural properties and chemical composition of the CIGS films are studied by an X-ray diffractometer (XRD) and an X-ray fluorescent spectrometer (XRF), respectively. A scanning electron microscope (SEM) is used to study the surface morphology. Lots of uncommon triangle islands and cavities are found on some planes of the CIGS thin films. We investigate the formation mechanism of these triangle islands. It is found that the planes with the triangle islands are (1 1 2) planes terminated by Se atoms. Se ad-dimer as a nucleus, Cu diffusion from CIGS grains brings the epitaxial triangle islands which grow with a two-dimensional layered mode. The film with Cu/(Ga + In) = 0.94–0.98 is one key of the formation of these islands. The triangle cavities are formed due to the insufficient coalescence of triangle islands. The growth of triangle islands brings a compact surface with large layered grains and many jagged edges, but no triangle cavity. Finally, we compare the performance of solar cell with triangle islands and layered gains. It is found that the performance of solar cell with large layered gains is improved.
Directory of Open Access Journals (Sweden)
Si Putu Gede Gunawan Tista
2012-11-01
Full Text Available One of the ways to reduce energy consumption on the air plane and the other bluff bodies are by decreasing the drag. Drag isclosely related to the flow separation. The earlier separation, then the drag will increase more. Based of the fact the effort todecrease drag is conducted by manipulating the field of fluid flow. Stream manipulation was be done by installing Triangleobstacle in front of cylinder. The purpose of this research is to analyze the effect of various distance triangle obstacle in front ofcylinder on drag. The present experiment was done by placing triangle rod in front of the cylinder. In the present research, theexperiment was conducted in the wind tunnel, which consisted of blower, pitot pipe, manometer, cylinder pipe, and triangle rod.The triangle was positioned at L/D = 1.19, L/D = 1.43, L/D = 1.67, L/D = 1.9, L/D = 2.14, L/D = 2.38, L/D = 2.62, and L/D =2.86 by upstream from the cylinder. The triangle was 8 mm uniform side. The Reynolds number based on the cylinder diameter (D= 42 mm was Re = 1.81 x 104. The research results showed that the triangle rod could decrease the drag of cylinder. Coefficientdrag for cylinder without triangle rod was 0.1276 while the biggest decrease of coefficient of drag with triangle rod washappened at L/D = 1.43 which was 0.0188. It means that the drag of cylinder with triangle rod was 85.25% lower than thecylinder alone.
International Nuclear Information System (INIS)
Chodos, A.
1978-01-01
A version of lattice gauge theory is presented in which the shape of the lattice is not assumed at the outset but is a consequence of the dynamics. Other related features which are not specified a priori include the internal and space-time symmetry groups and the dimensionality of space-time. The theory possesses a much larger invariance group than the usual gauge group on a lattice, and has associated with it an integer k 0 analogous to the topological quantum numer of quantum chromodynamics. Families of semiclassical solutions are found which are labeled by k 0 and a second integer x, but the analysis is not carried far enough to determine which space-time and internal symmetry groups characterize the lowest-lying states of the theory
Effect of cosine current approximation in lattice cell calculations in cylindrical geometry
International Nuclear Information System (INIS)
Mohanakrishnan, P.
1978-01-01
It is found that one-dimensional cylindrical geometry reactor lattice cell calculations using cosine angular current approximation at spatial mesh interfaces give results surprisingly close to the results of accurate neutron transport calculations as well as experimental measurements. This is especially true for tight light water moderated lattices. Reasons for this close agreement are investigated here. By re-examining the effects of reflective and white cell boundary conditions in these calculations it is concluded that one major reason is the use of white boundary condition necessitated by the approximation of the two-dimensional reactor lattice cell by a one-dimensional one. (orig.) [de
Energy Technology Data Exchange (ETDEWEB)
Catterall, Simon; Kaplan, David B.; Unsal, Mithat
2009-03-31
We provide an introduction to recent lattice formulations of supersymmetric theories which are invariant under one or more real supersymmetries at nonzero lattice spacing. These include the especially interesting case of N = 4 SYM in four dimensions. We discuss approaches based both on twisted supersymmetry and orbifold-deconstruction techniques and show their equivalence in the case of gauge theories. The presence of an exact supersymmetry reduces and in some cases eliminates the need for fine tuning to achieve a continuum limit invariant under the full supersymmetry of the target theory. We discuss open problems.
Review of lattice results concerning low-energy particle physics
International Nuclear Information System (INIS)
Aoki, S.; Aoki, Y.; Brookhaven National Laboratory, Upton, NY; Becirevic, D.
2016-07-01
We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form factor f_+(0), arising in the semileptonic K→π transition at zero momentum transfer, as well as the decay constant ratio f_K/f_π and its consequences for the CKM matrix elements V_u_s and V_u_d. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)_L x SU(2)_R and SU(3)_L x SU(3)_R Chiral Perturbation Theory. We review the determination of the B_K parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for m_c and m_b (also new compared to the previous review), as well as those for D- and B-meson decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant α_s.
Review of lattice results concerning low-energy particle physics
Energy Technology Data Exchange (ETDEWEB)
Aoki, S. [Kyoto University, Yukawa Institute for Theoretical Physics, Kyoto (Japan); Aoki, Y. [Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya (Japan); Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States); Bernard, C. [Washington University, Department of Physics, Saint Louis, MO (United States); Blum, T. [Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States); University of Connecticut, Physics Department, Storrs, CT (United States); Colangelo, G.; Leutwyler, H.; Necco, S.; Wenger, U. [Institut fuer theoretische Physik, Universitaet Bern, Albert Einstein Center for Fundamental Physics, Bern (Switzerland); Della Morte, M. [University of Southern Denmark, CP3-Origins and Danish IAS, Odense M (Denmark); IFIC (CSIC), Paterna (Spain); Duerr, S. [Bergische Universitaet Wuppertal, Wuppertal (Germany); Juelich Supercomputing Center, Juelich (Germany); El-Khadra, A.X. [University of Illinois, Department of Physics, Urbana, IL (United States); Fukaya, H.; Onogi, T. [Osaka University, Department of Physics, Osaka (Japan); Horsley, R. [University of Edinburgh, School of Physics, Edinburgh (United Kingdom); Juettner, A.; Sachrajda, C.T. [University of Southampton, School of Physics and Astronomy, Southampton (United Kingdom); Kaneko, T. [High Energy Accelerator Research Organization (KEK), Ibaraki (Japan); Laiho, J. [University of Glasgow, SUPA, Department of Physics and Astronomy, Glasgow (United Kingdom); Syracuse University, Department of Physics, Syracuse, New York (United States); Lellouch, L. [Aix-Marseille Universite, CNRS, CPT, UMR 7332, Marseille (France); Universite de Toulon, CNRS, CPT, UMR 7332, La Garde (France); Lubicz, V. [Universita Roma Tre, Dipartimento di Matematica e Fisica, Rome (Italy); Sezione di Roma Tre, INFN, Rome (Italy); Lunghi, E. [Indiana University, Physics Department, Bloomington, IN (United States); Pena, C. [Universidad Autonoma de Madrid, Instituto de Fisica Teorica UAM/CSIC and Departamento de Fisica Teorica, Madrid (Spain); Sharpe, S.R. [University of Washington, Physics Department, Seattle, WA (United States); Simula, S. [Sezione di Roma Tre, INFN, Rome (Italy); Sommer, R. [NIC rate at DESY, Zeuthen (Germany); Water, R.S.V. de [Fermi National Accelerator Laboratory, Batavia, IL (United States); Vladikas, A. [Universita di Roma Tor Vergata, INFN, Sezione di Tor Vergata, c/o Dipartimento di Fisica, Rome (Italy); Wittig, H. [University of Mainz, PRISMA Cluster of Excellence, Institut fuer Kernphysik and Helmholtz Institute Mainz, Mainz (Germany); Collaboration: FLAG Working Group
2014-09-15
We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the lightquark masses, the form factor f{sub +}(0), arising in semileptonic K → π transition at zero momentum transfer, as well as the decay-constant ratio f{sub K}/f{sub π} of decay constants and its consequences for the CKM matrix elements V{sub us} and V{sub ud}. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2){sub L} x SU(2){sub R} andSU(3)L{sub L} x SU(3){sub R} Chiral Perturbation Theory and review the determination of the BK parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, we focus here on D- and B-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant α{sub s}. (orig.)
Hofstadter butterflies and magnetically induced band-gap quenching in graphene antidot lattices
DEFF Research Database (Denmark)
Pedersen, Jesper Goor; Pedersen, Thomas Garm
2013-01-01
We study graphene antidot lattices (GALs) in magnetic fields. Using a tight-binding model and a recursive Green's function technique that we extend to deal with periodic structures, we calculate Hofstadter butterflies of GALs. We compare the results to those obtained in a simpler gapped graphene ...
Global Coal Trade. From Tightness to Oversupply
International Nuclear Information System (INIS)
Cornot-Gandolphe, Sylvie
2013-01-01
Over the past four years, international coal trade has been reshaped by China's surging imports. China, which was still a net exporter in 2008, became the world's first coal importer in 2011, taking over the position that Japan has occupied for three decades. Its imports have continued their rising trend and reached a record level in 2012, despite the country's economic slowdown. China imported 289 million tons of coal in 2012, up 30% over 2011. It now accounts for 23% of global imports. Although China is the world's largest coal producer, several factors have contributed to the sudden rise in its imports, including the higher cost of domestic coal relative to international prices and bottlenecks in transporting domestic coal to south-eastern provinces. More recently, another event shook the international coal business: the United States have been back on the market. The collapse of U.S. gas prices, to $4/million Btu in 2011 and even $2.75/million Btu in 2012, linked with the 'shale gas revolution', has made coal uncompetitive in the electricity sector, its main outlet on the U.S. market. U.S. coal demand dropped 4% in 2011 and 11% in 2012. The reduction in domestic demand has forced U.S. miners to look for overseas outlets. Their exports surged by 31% in 2011 and 16% in 2012. They reached 112 million tons in 2012, more than twice the level of 2009. The United States, which almost disappeared from the international steam coal market in the 2000's, have regained a larger share of the total coal export market, 9% in 2012, against 6% in 2009. These developments, although not directly linked, have a huge impact on the global market and pricing of coal. Chinese imports have helped the market to quickly recover from its low level of 2008-2009. The speed and magnitude of China's coal imports even shifts the market from a sluggish to a tight situation. Prices started to rise after their collapse in the second half of 2008 caused by the economic and financial crisis
International Nuclear Information System (INIS)
Krojts, M.
1987-01-01
The book by the known american physicist-theoretist M.Kreuts represents the first monography in world literature, where a new perspective direction in elementary particle physics and quantum field theory - lattice formulation of gauge theories is stated systematically. Practically all main ideas of this direction are given. Material is stated in systematic and understandable form
Phenomenology Using Lattice QCD
Gupta, R.
2005-08-01
This talk provides a brief summary of the status of lattice QCD calculations of the light quark masses and the kaon bag parameter BK. Precise estimates of these four fundamental parameters of the standard model, i.e., mu, md, ms and the CP violating parameter η, help constrain grand unified models and could provide a window to new physics.
International Nuclear Information System (INIS)
Bali, G.S.
2005-01-01
I comment on progress of lattice QCD techniques and calculations. Recent results on pentaquark masses as well as of the spectrum of excited baryons are summarized and interpreted. The present state of calculations of quantities related to the nucleon structure and of electromagnetic transition form factors is surveyed
Finite lattice extrapolation algorithms
International Nuclear Information System (INIS)
Henkel, M.; Schuetz, G.
1987-08-01
Two algorithms for sequence extrapolation, due to von den Broeck and Schwartz and Bulirsch and Stoer are reviewed and critically compared. Applications to three states and six states quantum chains and to the (2+1)D Ising model show that the algorithm of Bulirsch and Stoer is superior, in particular if only very few finite lattice data are available. (orig.)
Williamson, S. Gill
2010-01-01
Will the cosmological multiverse, when described mathematically, have easily stated properties that are impossible to prove or disprove using mathematical physics? We explore this question by constructing lattice multiverses which exhibit such behavior even though they are much simpler mathematically than any likely cosmological multiverse.
de Raedt, Hans; von der Linden, W.; Binder, K
1995-01-01
In this chapter we review methods currently used to perform Monte Carlo calculations for quantum lattice models. A detailed exposition is given of the formalism underlying the construction of the simulation algorithms. We discuss the fundamental and technical difficulties that are encountered and
Scott, Paul
2006-01-01
A "convex" polygon is one with no re-entrant angles. Alternatively one can use the standard convexity definition, asserting that for any two points of the convex polygon, the line segment joining them is contained completely within the polygon. In this article, the author provides a solution to a problem involving convex lattice polygons.
International Nuclear Information System (INIS)
Autin, B.
1984-01-01
After a description of the constraints imposed by the cooling of Antiprotons on the lattice of the rings, the reasons which motivate the shape and the structure of these machines are surveyed. Linear and non-linear beam optics properties are treated with a special amplification to the Antiproton Accumulator. (orig.)
Review of lattice results concerning low-energy particle physics
DEFF Research Database (Denmark)
Aoki, Sinya; Aoki, Yasumichi; Bečirević, D.
2017-01-01
We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor f+(0) , arising in the semileptonic K→ π transition...... review the determination of the BK parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for mc and mb...... (also new compared to the previous review), as well as those for D- and B-meson-decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status...
Energy, economy and development (EED) triangle: Concerns for India
International Nuclear Information System (INIS)
Chaturvedi, A.; Samdarshi, S.K.
2011-01-01
In this paper we discuss issues involving energy security with economic growth and development that brings out (i) the dimension of physical security alternative, (ii) framework for a pan South East Asian platform to support energy security and (iii) requirement of promoting regional energy cooperation and specific energy peace initiatives. Sustaining projected economic growth rate coupled with energy security in future is a concern for all developing countries like India. The energy security of these nations is threatened by the disruption of energy supplies by ongoing energy terrorism and geopolitical conflicts in the region. India's geo-strategic position and increasing energy dependence raises concerns for its energy security. We discuss energy security, examine factors and approaches to attempt the energy security in the light of economic growth and development. - Highlights: → India's perspective on evolving energy security concepts and risks analysed. → Model in the form of EED triangle proposed. → New potential energy security alternatives proposed in the light of the model.
Energy, economy and development (EED) triangle: Concerns for India
Energy Technology Data Exchange (ETDEWEB)
Chaturvedi, A. [Department of Energy, Tezpur University, Tezpur 784028, Assam (India); Samdarshi, S.K., E-mail: drsksamdarshi@rediffmail.com [Department of Energy, Tezpur University, Tezpur 784028, Assam (India)
2011-08-15
In this paper we discuss issues involving energy security with economic growth and development that brings out (i) the dimension of physical security alternative, (ii) framework for a pan South East Asian platform to support energy security and (iii) requirement of promoting regional energy cooperation and specific energy peace initiatives. Sustaining projected economic growth rate coupled with energy security in future is a concern for all developing countries like India. The energy security of these nations is threatened by the disruption of energy supplies by ongoing energy terrorism and geopolitical conflicts in the region. India's geo-strategic position and increasing energy dependence raises concerns for its energy security. We discuss energy security, examine factors and approaches to attempt the energy security in the light of economic growth and development. - Highlights: > India's perspective on evolving energy security concepts and risks analysed. > Model in the form of EED triangle proposed. > New potential energy security alternatives proposed in the light of the model.
Experimental realization of the quantum metrological triangle experiment
Energy Technology Data Exchange (ETDEWEB)
Chenaud, B; Devoille, L; Steck, B; Feltin, N; Gonzalez-Cano, A; Poirier, W; Schopfer, F; Spengler, G; Djordjevic, S; Seron, O; Piquemal, F [Laboratoire national de metrologie et d' essais (LNE), Trappes (France); Lotkhov, S [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany)], E-mail: laurent.devoille@lne.fr
2009-02-01
The quantum metrological triangle experiment (QMTE) consists in realizing Ohm's law with Josephson (JE), quantum Hall (QHE) and single electron tunneling (SET) effects. The aim is to check the consistency of the link among the phenomenological constants K {sub J}, R{sub K} and Q {sub X} involved in these effects and theoretically expressed with the fundamental constants e and h. Such an experiment could be a contribution for a new definition of the systeme international d'unites (SI) base units. In the QMTE, a current generated by a SET device flows through a resistor calibrated against QHE standard and the voltage induced at its terminals is compared to the metrological voltage generated by a Josephson junctions array. At LNE, the studied SET devices are 3 junctions single electron pumps with on chip resistors. The quantized current generated by this pump is theoretically equal to ef (f is the frequency of the driving signals applied on the gates) and is measured through a cryogenic current comparator (CCC), which allows to amplify the low pumping current with a metrological accuracy. We will present and discuss the experimental set-up developed at LNE and the first results. In addition to the main aim of QMTE described above, these preliminary results are also a first step towards a determination of e.
Geology and resources of the Tar Sand Triangle, southeastern Utah
Energy Technology Data Exchange (ETDEWEB)
Dana, G.F.; Oliver, R.L.; Elliott, J.R.
1984-05-01
The Tar Sand Triangle is located in southeastern Utah between the Dirty Devil and Colorado Rivers and covers an area of about 200 square miles. The geology of the area consists of gently northwest dipping strata exposed in the box canyons and slopes of the canyonlands morphology. Strata in the area range in age from Jurassic to Permian. The majority of tar sand saturation is found in the Permian White Rim Sandstone Member of the Cutler Formation. The White Rim Sandstone Member consists of a clean, well-sorted sandstone which was deposited in a shallow marine environment. Resources were calculated from analytical data from the three coreholes drilled by the Laramie Energy Technology Center and other available data. The total in-place resources, determined from this study, are 6.3 billion barels. Previous estimates ranged from 2.9 to 16 million barrels. More coring and analyses will be necessary before a more accurate determination of resources can be attempted. 8 references, 11 figures, 7 tables.
Unquenched lattice upsilon spectroscopy
International Nuclear Information System (INIS)
Marcantonio, L.M.
2001-03-01
A non-relativistic effective theory of QCD (NRQCD) is used in calculations of the upsilon spectrum. Simultaneous multi-correlation fitting routines are used to yield lattice channel energies and amplitudes. The lattice configurations used were both dynamical, with two flavours of sea quarks included in the action; and quenched, with no sea quarks. These configurations were generated by the UKQCD collaboration. The dynamical configurations used were ''matched'', having the same lattice spacing, but differing in the sea quark mass. Thus, it was possible to analyse trends of observables with sea quark mass, in the certainty that the trend isn't partially due to varying lattice spacing. The lattice spacing used for spectroscopy was derived from the lattice 1 1 P 1 - 1 3 S 1 splitting. On each set of configurations two lattice bare b quark masses were used, giving kinetic masses bracketing the physical Υ mass. The only quantity showing a strong dependence on these masses was the hyperfine splitting, so it was interpolated to the real Υ mass. The radial and orbital splittings gave good agreement with experiment. The hyperfine splitting results showed a clear signal for unquenching and the dynamical hyperfine splitting results were extrapolated to a physical sea quark mass. This result, combined with the quenched result yielded a value for the hyperfine splitting at n f = 3, predicting an η b mass of 9.517(4) GeV. The NRQCD technique for obtaining a value of the strong coupling constant in the M-barS-bar scheme was followed. Using quenched and dynamical results a value was extrapolated to n f = 3. Employing a three loop beta function to run the coupling, with suitable matching conditions at heavy quark thresholds, the final result was obtained for n f = 5 at a scale equal to the Z boson mass. This result was α(5)/MS(Mz)=0.110(4). Two methods for finding the mass of the b quark in the MS scheme were employed. The results of both methods agree within error but the
Is this child sick? Usefulness of the Pediatric Assessment Triangle in emergency settings
Directory of Open Access Journals (Sweden)
Ana Fernandez
2017-11-01
Conclusions: The Pediatric Assessment Triangle is quickly spreading internationally and its clinical applicability is very promising. Nevertheless, it is imperative to promote research for clinical validation, especially for clinical use by emergency pediatricians and physicians.
College geometry an introduction to the modern geometry of the triangle and the circle
Altshiller-Court, Nathan
2007-01-01
The standard university-level text for decades, this volume offers exercises in construction problems, harmonic division, circle and triangle geometry, and other areas. 1952 edition, revised and enlarged by the author.
Employees from EPA’s Research Triangle Park (RTP) campus serve as guest speakers at local schools and in the community. Hands-on activities and interactive discussions supplement classroom instruction and promote environmental awareness
2011-03-01
This project addressed sustainable transportation in the Texas Urban Triangle (TUT) by conducting a pilot : project at the county scale. The project tested and developed the multi-attribute Spatial Decision Support : System (SDSS) developed in 2009 u...
Energy Technology Data Exchange (ETDEWEB)
Wu Hongchun [Nuclear Engineering Department, Xi' an Jiaotong University, Xi' an 710049, Shaanxi (China)]. E-mail: hongchun@mail.xjtu.edu.cn; Liu Pingping [Nuclear Engineering Department, Xi' an Jiaotong University, Xi' an 710049, Shaanxi (China); Zhou Yongqiang [Nuclear Engineering Department, Xi' an Jiaotong University, Xi' an 710049, Shaanxi (China); Cao Liangzhi [Nuclear Engineering Department, Xi' an Jiaotong University, Xi' an 710049, Shaanxi (China)
2007-01-15
In the advanced reactor, the fuel assembly or core with unstructured geometry is frequently used and for calculating its fuel assembly, the transmission probability method (TPM) has been used widely. However, the rectangle or hexagon meshes are mainly used in the TPM codes for the normal core structure. The triangle meshes are most useful for expressing the complicated unstructured geometry. Even though finite element method and Monte Carlo method is very good at solving unstructured geometry problem, they are very time consuming. So we developed the TPM code based on the triangle meshes. The TPM code based on the triangle meshes was applied to the hybrid fuel geometry, and compared with the results of the MCNP code and other codes. The results of comparison were consistent with each other. The TPM with triangle meshes would thus be expected to be able to apply to the two-dimensional arbitrary fuel assembly.
CSIR Research Space (South Africa)
Vismer, HF
1995-08-01
Full Text Available Atmospheric fungal spores were monitored in Vanderbijlpark for the period 1991-92 as part of the Vaal triangle air pollution health study of the medical research council and the CSIR. Cladosporium, Aspergillus/ Penicillium, Alternaria and Epicoccum...
Report #09-P-0227, August 31, 2009. Vulnerability testing conducted in April 2009 of EPA’s Research Triangle Park Finance Center network identified Internet Protocol addresses with several highrisk vulnerabilities.
2009-03-01
This study takes a megaregion approach to project future travel demand and choice of transport : modes in the Texas Triangle, which is encompassed by four major metropolitan areas, Dallas-Fort : Worth, Houston, San Antonio, and Austin. The model was ...
Tightness Entropic Uncertainty Relation in Quantum Markovian-Davies Environment
Zhang, Jun; Liu, Liang; Han, Yan
2018-05-01
In this paper, we investigate the tightness of entropic uncertainty relation in the absence (presence) of the quantum memory which the memory particle being weakly coupled to a decohering Davies-type Markovian environment. The results show that the tightness of the quantum uncertainty relation can be controlled by the energy relaxation time F, the dephasing time G and the rescaled temperature p, the perfect tightness can be arrived by dephasing and energy relaxation satisfying F = 2G and p = 1/2. In addition, the tightness of the memory-assisted entropic uncertainty relation and the entropic uncertainty relation can be influenced mainly by the purity. While in memory-assisted model, the purity and quantum correlation can also influence the tightness actively while the quantum entanglement can influence the tightness slightly.
Improved Density Functional Tight Binding Potentials for Metalloid Aluminum Clusters
2016-06-01
unlimited IMPROVED DENSITY-FUNCTIONAL TIGHT BINDING POTENTIALS FOR METALLOID ALUMINUM CLUSTERS by Joon H. Kim June 2016 Thesis Advisor...DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE IMPROVED DENSITY-FUNCTIONAL TIGHT BINDING POTENTIALS FOR METALLOID ALUMINUM CLUSTERS 5. FUNDING...repulsive potentials for use in density-functional tight binding (DFTB) simulations of low-valence aluminum metalloid clusters . These systems are under
Naturally fractured tight gas reservoir detection optimization
Energy Technology Data Exchange (ETDEWEB)
NONE
1999-04-30
In March, work continued on characterizing probabilities for determining natural fracturing associated with the GGRB for the Upper Cretaceous tight gas plays. Structural complexity, based on potential field data and remote sensing data was completed. A resource estimate for the Frontier and Mesa Verde play was also completed. Further, work was also conducted to determine threshold economics for the play based on limited current production in the plays in the Wamsutter Ridge area. These analyses culminated in a presentation at FETC on 24 March 1999 where quantified natural fracture domains, mapped on a partition basis, which establish ''sweet spot'' probability for natural fracturing, were reviewed. That presentation is reproduced here as Appendix 1. The work plan for the quarter of January 1, 1999--March 31, 1999 comprised five tasks: (1) Evaluation of the GGRB partitions for structural complexity that can be associated with natural fractures, (2) Continued resource analysis of the balance of the partitions to determine areas with higher relative gas richness, (3) Gas field studies, (4) Threshold resource economics to determine which partitions would be the most prospective, and (5) Examination of the area around the Table Rock 4H well.
Three-coloring graphs with no induced seven-vertex path II : using a triangle
Chudnovsky, Maria; Maceli, Peter; Zhong, Mingxian
2015-01-01
In this paper, we give a polynomial time algorithm which determines if a given graph containing a triangle and no induced seven-vertex path is 3-colorable, and gives an explicit coloring if one exists. In previous work, we gave a polynomial time algorithm for three-coloring triangle-free graphs with no induced seven-vertex path. Combined, our work shows that three-coloring a graph with no induced seven-vertex path can be done in polynomial time.
Dose-response relationship of sertindole and haloperidol using the pharmacopsychometric triangle
DEFF Research Database (Denmark)
Bech, P; Tanghøj, P; Andreasson, K
2011-01-01
Renewed insight into dose-related effects of sertindole and haloperidol was sought by re-analysing published data for antipsychotic effect, extrapyramidal effect, and patient wellbeing - i.e., the important pharmacopsychometric triangle domains.......Renewed insight into dose-related effects of sertindole and haloperidol was sought by re-analysing published data for antipsychotic effect, extrapyramidal effect, and patient wellbeing - i.e., the important pharmacopsychometric triangle domains....
Functioning of the knowledge triangle in the example of IT education
Directory of Open Access Journals (Sweden)
ZHIVITSKAYA H.
2015-06-01
Full Text Available The analysis of the interactions between knowledge triangle components in IT-education in the Republic of Belarus is described. This paper describes the results of research in the framework of the program of the European Union Tempus IV «Fostering the Knowledge Triangle in Belarus, Ukraine and Moldova» - «FKTBUM». The analysis of the obstacles to the effective integration of higher education, research and innovation is performed.
The coral triangle initiative: What are we missing? A case study from Aceh
Rudi, Edi
2012-10-01
Abstract The Coral Triangle Initiative is an ambitious attempt to conserve the marine biodiversity hotspot known as the Coral Triangle. However, the reef fauna in many nearby regions remains poorly explored and, consequently, the focus on the Coral Triangle risks overlooking other areas of high conservation significance. One region of potential significance, Aceh, Indonesia, has not been visited by coral taxonomists since the Dutch colonial period. Here we document the species richness of scleractinian corals of Pulau Weh, Aceh. We also compare the species richness of the genus Acropora at 3-5 sites in each of nine regions in Indonesia and Papua New Guinea. Although dominated by widespread Indo-Pacific species, the coral fauna of Pulau Weh is also the eastern and western boundary for many Indian Ocean and Pacific Ocean species, respectively. We identified a total of 133 scleractinian species, of which three have been previously recorded only in the western Indian Ocean and five are presently undescribed. The mean species richness of the Acropora at Pulau Weh is similar to regions within the Coral Triangle. This high species richness plus the high proportion of endemics suggests that the Andaman Sea is of similarly high conservation value to the Coral Triangle. We suggest that an international initiative similar to the Coral Triangle Initiative is required to conserve this region, which includes the territorial waters of six countries. © 2012 Fauna & Flora International.
Lost-in-Space Star Identification Using Planar Triangle Principal Component Analysis Algorithm
Directory of Open Access Journals (Sweden)
Fuqiang Zhou
2015-01-01
Full Text Available It is a challenging task for a star sensor to implement star identification and determine the attitude of a spacecraft in the lost-in-space mode. Several algorithms based on triangle method are proposed for star identification in this mode. However, these methods hold great time consumption and large guide star catalog memory size. The star identification performance of these methods requires improvements. To address these problems, a star identification algorithm using planar triangle principal component analysis is presented here. A star pattern is generated based on the planar triangle created by stars within the field of view of a star sensor and the projection of the triangle. Since a projection can determine an index for a unique triangle in the catalog, the adoption of the k-vector range search technique makes this algorithm very fast. In addition, a sharing star validation method is constructed to verify the identification results. Simulation results show that the proposed algorithm is more robust than the planar triangle and P-vector algorithms under the same conditions.
Superspace approach to lattice supersymmetry
International Nuclear Information System (INIS)
Kostelecky, V.A.; Rabin, J.M.
1984-01-01
We construct a cubic lattice of discrete points in superspace, as well as a discrete subgroup of the supersymmetry group which maps this ''superlattice'' into itself. We discuss the connection between this structure and previous versions of lattice supersymmetry. Our approach clarifies the mathematical problems of formulating supersymmetric lattice field theories and suggests new methods for attacking them
Basis reduction for layered lattices
Torreão Dassen, Erwin
2011-01-01
We develop the theory of layered Euclidean spaces and layered lattices. We present algorithms to compute both Gram-Schmidt and reduced bases in this generalized setting. A layered lattice can be seen as lattices where certain directions have infinite weight. It can also be
International Nuclear Information System (INIS)
Woloshyn, R.M.
1988-03-01
The basic concepts of the Lagrangian formulation of lattice field theory are discussed. The Wilson and staggered schemes for dealing with fermions on the lattice are described. Some recent results for hadron masses and vector and axial vector current matrix elements in lattice QCD are reviewed. (Author) (118 refs., 16 figs.)
Basis reduction for layered lattices
E.L. Torreão Dassen (Erwin)
2011-01-01
htmlabstractWe develop the theory of layered Euclidean spaces and layered lattices. With this new theory certain problems that usually are solved by using classical lattices with a "weighting" gain a new, more natural form. Using the layered lattice basis reduction algorithms introduced here these
Digital Rock Studies of Tight Porous Media
Energy Technology Data Exchange (ETDEWEB)
Silin, Dmitriy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2012-08-07
This technical report summarizes some recently developed approaches to studies of rock properties at a pore scale. Digital rock approach is complementary to laboratory and field studies. It can be especially helpful in situations where experimental data are uncertain, or are difficult or impossible to obtain. Digitized binary images of the pore geometries of natural rocks obtained by different imaging techniques are the input data. Computer-generated models of natural rocks can be used instead of images in a case where microtomography data are unavailable, or the resolution of the tools is insufficient to adequately characterize the features of interest. Simulations of creeping viscous flow in pores produce estimates of Darcy permeability. Maximal Inscribed Spheres calculations estimate two-phase fluid distribution in capillary equilibrium. A combination of both produce relative permeability curves. Computer-generated rock models were employed to study two-phase properties of fractured rocks, or tight sands with slit-like pores, too narrow to be characterized with micro-tomography. Various scenarios can simulate different fluid displacement mechanisms, from piston-like drainage to liquid dropout at the dew point. A finite differences discretization of Stokes equation is developed to simulate flow in the pore space of natural rocks. The numerical schemes are capable to handle both no-slip and slippage flows. An upscaling procedure estimates the permeability by subsampling a large data set. Capillary equilibrium and capillary pressure curves are efficiently estimated with the method of maximal inscribed spheres both an arbitrary contact angle. The algorithms can handle gigobytes of data on a desktop workstation. Customized QuickHull algorithms model natural rocks. Capillary pressure curves evaluated from computer-generated images mimic those obtained for microtomography data.
US production of natural gas from tight reservoirs
International Nuclear Information System (INIS)
1993-01-01
For the purposes of this report, tight gas reservoirs are defined as those that meet the Federal Energy Regulatory Commission's (FERC) definition of tight. They are generally characterized by an average reservoir rock permeability to gas of 0.1 millidarcy or less and, absent artificial stimulation of production, by production rates that do not exceed 5 barrels of oil per day and certain specified daily volumes of gas which increase with the depth of the reservoir. All of the statistics presented in this report pertain to wells that have been classified, from 1978 through 1991, as tight according to the FERC; i.e., they are ''legally tight'' reservoirs. Additional production from ''geologically tight'' reservoirs that have not been classified tight according to the FERC rules has been excluded. This category includes all producing wells drilled into legally designated tight gas reservoirs prior to 1978 and all producing wells drilled into physically tight gas reservoirs that have not been designated legally tight. Therefore, all gas production referenced herein is eligible for the Section 29 tax credit. Although the qualification period for the credit expired at the end of 1992, wells that were spudded (began to be drilled) between 1978 and May 1988, and from November 5, 1990, through year end 1992, are eligible for the tax credit for a subsequent period of 10 years. This report updates the EIA's tight gas production information through 1991 and considers further the history and effect on tight gas production of the Federal Government's regulatory and tax policy actions. It also provides some high points of the geologic background needed to understand the nature and location of low-permeability reservoirs
Energy Technology Data Exchange (ETDEWEB)
Buechner, O. [Zentralinstitut fuer Angewandte Mathematik ZAM, 52425 Juelich (Germany); Ernst, M. [Deutsches Elektronen-Synchrotron DESY, 22603 Hamburg (Germany); Jansen, K. [John von Neumann-Institut fuer Computing NIC/DESY, 15738 Zeuthen (Germany); Lippert, Th. [Zentralinstitut fuer Angewandte Mathematik ZAM, 52425 Juelich (Germany); Melkumyan, D. [Deutsches Elektronen-Synchrotron DESY, 15738 Zeuthen (Germany); Orth, B. [Zentralinstitut fuer Angewandte Mathematik ZAM, 52425 Juelich (Germany); Pleiter, D. [John von Neumann-Institut fuer Computing NIC/DESY, 15738 Zeuthen (Germany)]. E-mail: dirk.pleiter@desy.de; Stueben, H. [Konrad-Zuse-Institut fuer Informationstechnik ZIB, 14195 Berlin (Germany); Wegner, P. [Deutsches Elektronen-Synchrotron DESY, 15738 Zeuthen (Germany); Wollny, S. [Konrad-Zuse-Institut fuer Informationstechnik ZIB, 14195 Berlin (Germany)
2006-04-01
As the need for computing resources to carry out numerical simulations of Quantum Chromodynamics (QCD) formulated on a lattice has increased significantly, efficient use of the generated data has become a major concern. To improve on this, groups plan to share their configurations on a worldwide level within the International Lattice DataGrid (ILDG). Doing so requires standardized description of the configurations, standards on binary file formats and common middleware interfaces. We describe the requirements and problems, and discuss solutions. Furthermore, an overview is given on the implementation of the LatFor DataGrid [http://www-zeuthen.desy.de/latfor/ldg], a France/German/Italian grid that will be one of the regional grids within the ILDG grid-of-grids concept.
International Nuclear Information System (INIS)
Borsanyi, Sz.; Kampert, K.H.; Fodor, Z.; Forschungszentrum Juelich; Eoetvoes Univ., Budapest
2016-06-01
We present a full result for the equation of state (EoS) in 2+1+1 (up/down, strange and charm quarks are present) flavour lattice QCD. We extend this analysis and give the equation of state in 2+1+1+1 flavour QCD. In order to describe the evolution of the universe from temperatures several hundreds of GeV to the MeV scale we also include the known effects of the electroweak theory and give the effective degree of freedoms. As another application of lattice QCD we calculate the topological susceptibility (χ) up to the few GeV temperature region. These two results, EoS and χ, can be used to predict the dark matter axion's mass in the post-inflation scenario and/or give the relationship between the axion's mass and the universal axionic angle, which acts as a initial condition of our universe.
International Nuclear Information System (INIS)
Lutz, H.D.; Willich, P.
1977-01-01
The FIR absorption spectra of pyrite type compounds RuS 2 , RuSsub(2-x)Sesub(x), RuSe 2 , RuTe 2 , OsS 2 , OsSe 2 , and PtP 2 as well as loellingite type phosphides FeP 2 , RuP 2 , and OsP 2 are reported. For RuS 2 , RuSe 2 , RuTe 2 , OsS 2 , and PtP 2 all of the five infrared allowed modes (k = 0) are observed. As a first result of a numerical normal coordinate treatment vibration forms of pyrite structure are communicated. The spectra show that lattice forces of corresponding sulfides, tellurides, and phosphides are about the same strength, but increase strongly by substitution of iron by ruthenium and especially of ruthenium by osmium. The lattice constants of the RuSsub(2-x)Sesub(x) solid solution obey Vegard's rule. (author)
Solórzano, S.; Mendoza, M.; Succi, S.; Herrmann, H. J.
2018-01-01
We present a numerical scheme to solve the Wigner equation, based on a lattice discretization of momentum space. The moments of the Wigner function are recovered exactly, up to the desired order given by the number of discrete momenta retained in the discretization, which also determines the accuracy of the method. The Wigner equation is equipped with an additional collision operator, designed in such a way as to ensure numerical stability without affecting the evolution of the relevant moments of the Wigner function. The lattice Wigner scheme is validated for the case of quantum harmonic and anharmonic potentials, showing good agreement with theoretical results. It is further applied to the study of the transport properties of one- and two-dimensional open quantum systems with potential barriers. Finally, the computational viability of the scheme for the case of three-dimensional open systems is also illustrated.
Lattice Quantum Chromodynamics
Sachrajda, C T
2016-01-01
I review the the application of the lattice formulation of QCD and large-scale numerical simulations to the evaluation of non-perturbative hadronic effects in Standard Model Phenomenology. I present an introduction to the elements of the calculations and discuss the limitations both in the range of quantities which can be studied and in the precision of the results. I focus particularly on the extraction of the QCD parameters, i.e. the quark masses and the strong coupling constant, and on important quantities in flavour physics. Lattice QCD is playing a central role in quantifying the hadronic effects necessary for the development of precision flavour physics and its use in exploring the limits of the Standard Model and in searches for inconsistencies which would signal the presence of new physics.
Lattices of dielectric resonators
Trubin, Alexander
2016-01-01
This book provides the analytical theory of complex systems composed of a large number of high-Q dielectric resonators. Spherical and cylindrical dielectric resonators with inferior and also whispering gallery oscillations allocated in various lattices are considered. A new approach to S-matrix parameter calculations based on perturbation theory of Maxwell equations, developed for a number of high-Q dielectric bodies, is introduced. All physical relationships are obtained in analytical form and are suitable for further computations. Essential attention is given to a new unified formalism of the description of scattering processes. The general scattering task for coupled eigen oscillations of the whole system of dielectric resonators is described. The equations for the expansion coefficients are explained in an applicable way. The temporal Green functions for the dielectric resonator are presented. The scattering process of short pulses in dielectric filter structures, dielectric antennas and lattices of d...
International Nuclear Information System (INIS)
Hasenfratz, A.; Hasenfratz, P.
1985-01-01
This paper deals almost exclusively with applications in QCD. Presumably QCD will remain in the center of lattice calculations in the near future. The existing techniques and the available computer resources should be able to produce trustworthy results in pure SU(3) gauge theory and in quenched hadron spectroscopy. Going beyond the quenched approximation might require some technical breakthrough or exceptional computer resources, or both. Computational physics has entered high-energy physics. From this point of view, lattice QCD is only one (although the most important, at present) of the research fields. Increasing attention is devoted to the study of other QFTs. It is certain that the investigation of nonasymptotically free theories, the Higgs phenomenon, or field theories that are not perturbatively renormalizable will be important research areas in the future
Lattice degeneracies of geometric fermions
International Nuclear Information System (INIS)
Raszillier, H.
1983-05-01
We give the minimal numbers of degrees of freedom carried by geometric fermions on all lattices of maximal symmetries in d = 2, 3, and 4 dimensions. These numbers are lattice dependent, but in the (free) continuum limit, part of the degrees of freedom have to escape to infinity by a Wilson mechanism built in, and 2sup(d) survive for any lattice. On self-reciprocal lattices we compare the minimal numbers of degrees of freedom of geometric fermions with the minimal numbers of naive fermions on these lattices and argue that these numbers are equal. (orig.)
International Nuclear Information System (INIS)
1962-01-01
The panel was attended by prominent physicists from most of the well-known laboratories in the field of light-water lattices, who exchanged the latest information on the status of work in their countries and discussed both the theoretical and the experimental aspects of the subjects. The supporting papers covered most problems, including criticality, resonance absorption, thermal utilization, spectrum calculations and the physics of plutonium bearing systems. Refs, figs and tabs
Diffusion in heterogeneous lattices
Czech Academy of Sciences Publication Activity Database
Tarasenko, Alexander; Jastrabík, Lubomír
2010-01-01
Roč. 256, č. 17 (2010), s. 5137-5144 ISSN 0169-4332 R&D Projects: GA AV ČR KAN301370701; GA MŠk(CZ) 1M06002 Institutional research plan: CEZ:AV0Z10100522 Keywords : lattice- gas systems * diffusion * Monte Carlo simulations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.795, year: 2010
Automated lattice data generation
Directory of Open Access Journals (Sweden)
Ayyar Venkitesh
2018-01-01
Full Text Available The process of generating ensembles of gauge configurations (and measuring various observables over them can be tedious and error-prone when done “by hand”. In practice, most of this procedure can be automated with the use of a workflow manager. We discuss how this automation can be accomplished using Taxi, a minimal Python-based workflow manager built for generating lattice data. We present a case study demonstrating this technology.
Automated lattice data generation
Ayyar, Venkitesh; Hackett, Daniel C.; Jay, William I.; Neil, Ethan T.
2018-03-01
The process of generating ensembles of gauge configurations (and measuring various observables over them) can be tedious and error-prone when done "by hand". In practice, most of this procedure can be automated with the use of a workflow manager. We discuss how this automation can be accomplished using Taxi, a minimal Python-based workflow manager built for generating lattice data. We present a case study demonstrating this technology.
Energy Technology Data Exchange (ETDEWEB)
Kumar, J [Agra Coll. (India). Dept. of Physics
1977-03-01
In the present work, a local model pseudopotential has been proposed to study the lattice dynamics of thorium. The model potential depends on the core and ionic radii, and accounts for the s-d-f hybridization effects in a phenomenological way. When this form of potential is applied to derive the photon dispersion curves of Th, sufficiently good agreement is found between the computed and experimental results.
International Nuclear Information System (INIS)
Bowler, Ken
1990-01-01
One of the major recent developments in particle theory has been the use of very high performance computers to obtain approximate numerical solutions of quantum field theories by formulating them on a finite space-time lattice. The great virtue of this new technique is that it avoids the straitjacket of perturbation theory and can thus attack new, but very fundamental problems, such as the calculation of hadron masses in quark-gluon field theory (quantum chromodynamics - QCD)
Adamatzky, Andrew
2015-01-01
The book gives a comprehensive overview of the state-of-the-art research and engineering in theory and application of Lattice Automata in design and control of autonomous Robots. Automata and robots share the same notional meaning. Automata (originated from the latinization of the Greek word “αυτόματον”) as self-operating autonomous machines invented from ancient years can be easily considered the first steps of robotic-like efforts. Automata are mathematical models of Robots and also they are integral parts of robotic control systems. A Lattice Automaton is a regular array or a collective of finite state machines, or automata. The Automata update their states by the same rules depending on states of their immediate neighbours. In the context of this book, Lattice Automata are used in developing modular reconfigurable robotic systems, path planning and map exploration for robots, as robot controllers, synchronisation of robot collectives, robot vision, parallel robotic actuators. All chapters are...
Digital lattice gauge theories
Zohar, Erez; Farace, Alessandro; Reznik, Benni; Cirac, J. Ignacio
2017-02-01
We propose a general scheme for a digital construction of lattice gauge theories with dynamical fermions. In this method, the four-body interactions arising in models with 2 +1 dimensions and higher are obtained stroboscopically, through a sequence of two-body interactions with ancillary degrees of freedom. This yields stronger interactions than the ones obtained through perturbative methods, as typically done in previous proposals, and removes an important bottleneck in the road towards experimental realizations. The scheme applies to generic gauge theories with Lie or finite symmetry groups, both Abelian and non-Abelian. As a concrete example, we present the construction of a digital quantum simulator for a Z3 lattice gauge theory with dynamical fermionic matter in 2 +1 dimensions, using ultracold atoms in optical lattices, involving three atomic species, representing the matter, gauge, and auxiliary degrees of freedom, that are separated in three different layers. By moving the ancilla atoms with a proper sequence of steps, we show how we can obtain the desired evolution in a clean, controlled way.
Dielectric lattice gauge theory
International Nuclear Information System (INIS)
Mack, G.
1983-06-01
Dielectric lattice gauge theory models are introduced. They involve variables PHI(b)epsilong that are attached to the links b = (x+esub(μ),x) of the lattice and take their values in the linear space g which consists of real linear combinations of matrices in the gauge group G. The polar decomposition PHI(b)=U(b)osub(μ)(x) specifies an ordinary lattice gauge field U(b) and a kind of dielectric field epsilonsub(ij)proportionalosub(i)osub(j)sup(*)deltasub(ij). A gauge invariant positive semidefinite kinetic term for the PHI-field is found, and it is shown how to incorporate Wilson fermions in a way which preserves Osterwalder Schrader positivity. Theories with G = SU(2) and without matter fields are studied in some detail. It is proved that confinement holds, in the sense that Wilson loop expectation values show an area law decay, if the Euclidean action has certain qualitative features which imply that PHI = 0 (i.e. dielectric field identical 0) is the unique maximum of the action. (orig.)
Dielectric lattice gauge theory
International Nuclear Information System (INIS)
Mack, G.
1984-01-01
Dielectric lattice gauge theory models are introduced. They involve variables PHI(b)element ofG that are attached to the links b = (x+esub(μ), x) of the lattice and take their values in the linear space G which consists of real linear combinations of matrices in the gauge group G. The polar decomposition PHI(b)=U(b)sigmasub(μ)(x) specifies an ordinary lattice gauge field U(b) and a kind of dielectric field epsilonsub(ij)proportional sigmasub(i)sigmasub(j)sup(*)deltasub(ij). A gauge invariant positive semidefinite kinetic term for the PHI-field is found, and it is shown how to incorporate Wilson fermions in a way which preserves Osterwalder-Schrader positivity. Theories with G = SU(2) and without matter fields are studied in some detail. It is proved that confinement holds, in the sense that Wilson-loop expectation values show an area law decay, if the euclidean action has certain qualitative features which imply that PHI=0 (i.e. dielectric field identical 0) is the unique maximum of the action. (orig.)
Toward lattice fractional vector calculus
Tarasov, Vasily E.
2014-09-01
An analog of fractional vector calculus for physical lattice models is suggested. We use an approach based on the models of three-dimensional lattices with long-range inter-particle interactions. The lattice analogs of fractional partial derivatives are represented by kernels of lattice long-range interactions, where the Fourier series transformations of these kernels have a power-law form with respect to wave vector components. In the continuum limit, these lattice partial derivatives give derivatives of non-integer order with respect to coordinates. In the three-dimensional description of the non-local continuum, the fractional differential operators have the form of fractional partial derivatives of the Riesz type. As examples of the applications of the suggested lattice fractional vector calculus, we give lattice models with long-range interactions for the fractional Maxwell equations of non-local continuous media and for the fractional generalization of the Mindlin and Aifantis continuum models of gradient elasticity.
Air tightness measurements in older Danish single-family houses
DEFF Research Database (Denmark)
Mortensen, Lone Hedegaard; Bergsøe, Niels Christian
2017-01-01
of the building envelope of older buildings despite the fact that the air tightness has a major influence on the energy use. In connection with renovation of the Danish building stock, the coming years will see increased focus on the air tightness of the building envelope like in other countries. This paper...
Differences between tight and loose cultures : A 33-nation study
Gelfand, M.J.; Raver, R.L.; Nishii, L.; Leslie, L.M.; Lun, J.; Lim, B.C.; Van de Vliert, E.
2011-01-01
With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated
Dielectric response of molecules in empirical tight-binding theory
Boykin, Timothy B.; Vogl, P.
2002-01-01
In this paper we generalize our previous approach to electromagnetic interactions within empirical tight-binding theory to encompass molecular solids and isolated molecules. In order to guarantee physically meaningful results, we rederive the expressions for relevant observables using commutation relations appropriate to the finite tight-binding Hilbert space. In carrying out this generalization, we examine in detail the consequences of various prescriptions for the position and momentum operators in tight binding. We show that attempting to fit parameters of the momentum matrix directly generally results in a momentum operator which is incompatible with the underlying tight-binding model, while adding extra position parameters results in numerous difficulties, including the loss of gauge invariance. We have applied our scheme, which we term the Peierls-coupling tight-binding method, to the optical dielectric function of the molecular solid PPP, showing that this approach successfully predicts its known optical properties even in the limit of isolated molecules.
Andreopoulos, Bill; Winter, Christof; Labudde, Dirk; Schroeder, Michael
2009-06-27
A lot of high-throughput studies produce protein-protein interaction networks (PPINs) with many errors and missing information. Even for genome-wide approaches, there is often a low overlap between PPINs produced by different studies. Second-level neighbors separated by two protein-protein interactions (PPIs) were previously used for predicting protein function and finding complexes in high-error PPINs. We retrieve second level neighbors in PPINs, and complement these with structural domain-domain interactions (SDDIs) representing binding evidence on proteins, forming PPI-SDDI-PPI triangles. We find low overlap between PPINs, SDDIs and known complexes, all well below 10%. We evaluate the overlap of PPI-SDDI-PPI triangles with known complexes from Munich Information center for Protein Sequences (MIPS). PPI-SDDI-PPI triangles have ~20 times higher overlap with MIPS complexes than using second-level neighbors in PPINs without SDDIs. The biological interpretation for triangles is that a SDDI causes two proteins to be observed with common interaction partners in high-throughput experiments. The relatively few SDDIs overlapping with PPINs are part of highly connected SDDI components, and are more likely to be detected in experimental studies. We demonstrate the utility of PPI-SDDI-PPI triangles by reconstructing myosin-actin processes in the nucleus, cytoplasm, and cytoskeleton, which were not obvious in the original PPIN. Using other complementary datatypes in place of SDDIs to form triangles, such as PubMed co-occurrences or threading information, results in a similar ability to find protein complexes. Given high-error PPINs with missing information, triangles of mixed datatypes are a promising direction for finding protein complexes. Integrating PPINs with SDDIs improves finding complexes. Structural SDDIs partially explain the high functional similarity of second-level neighbors in PPINs. We estimate that relatively little structural information would be sufficient
Directory of Open Access Journals (Sweden)
Labudde Dirk
2009-06-01
Full Text Available Abstract Background A lot of high-throughput studies produce protein-protein interaction networks (PPINs with many errors and missing information. Even for genome-wide approaches, there is often a low overlap between PPINs produced by different studies. Second-level neighbors separated by two protein-protein interactions (PPIs were previously used for predicting protein function and finding complexes in high-error PPINs. We retrieve second level neighbors in PPINs, and complement these with structural domain-domain interactions (SDDIs representing binding evidence on proteins, forming PPI-SDDI-PPI triangles. Results We find low overlap between PPINs, SDDIs and known complexes, all well below 10%. We evaluate the overlap of PPI-SDDI-PPI triangles with known complexes from Munich Information center for Protein Sequences (MIPS. PPI-SDDI-PPI triangles have ~20 times higher overlap with MIPS complexes than using second-level neighbors in PPINs without SDDIs. The biological interpretation for triangles is that a SDDI causes two proteins to be observed with common interaction partners in high-throughput experiments. The relatively few SDDIs overlapping with PPINs are part of highly connected SDDI components, and are more likely to be detected in experimental studies. We demonstrate the utility of PPI-SDDI-PPI triangles by reconstructing myosin-actin processes in the nucleus, cytoplasm, and cytoskeleton, which were not obvious in the original PPIN. Using other complementary datatypes in place of SDDIs to form triangles, such as PubMed co-occurrences or threading information, results in a similar ability to find protein complexes. Conclusion Given high-error PPINs with missing information, triangles of mixed datatypes are a promising direction for finding protein complexes. Integrating PPINs with SDDIs improves finding complexes. Structural SDDIs partially explain the high functional similarity of second-level neighbors in PPINs. We estimate that
The subatlantic triangle: gateway to early localization of the atlantoaxial vertebral artery.
Tayebi Meybodi, Ali; Gandhi, Sirin; Preul, Mark C; Lawton, Michael T
2018-04-27
OBJECTIVE Exposure of the vertebral artery (VA) between C-1 and C-2 vertebrae (atlantoaxial VA) may be necessary in a variety of pathologies of the craniovertebral junction. Current methods to expose this segment of the VA entail sharp dissection of muscles close to the internal jugular vein and the spinal accessory nerve. The present study assesses the technique of exposing the atlantoaxial VA through a newly defined muscular triangle at the craniovertebral junction. METHODS Five cadaveric heads were prepared for surgical simulation in prone position, turned 30°-45° toward the side of exposure. The atlantoaxial VA was exposed through the subatlantic triangle after reflecting the sternocleidomastoid and splenius capitis muscles inferiorly. The subatlantic triangle was formed by 3 groups of muscles: 1) the levator scapulae and splenius cervicis muscles inferiorly and laterally, 2) the longissimus capitis muscle inferiorly and medially, and 3) the inferior oblique capitis superiorly. The lengths of the VA exposed through the triangle before and after unroofing the C-2 transverse foramen were measured. RESULTS The subatlantic triangle consistently provided access to the whole length of atlantoaxial VA. The average length of the VA exposed via the subatlantic triangle was 19.5 mm. This average increased to 31.5 mm after the VA was released at the C-2 transverse foramen. CONCLUSIONS The subatlantic triangle provides a simple and straightforward pathway to expose the atlantoaxial VA. The proposed method may be useful during posterior approaches to the craniovertebral junction should early exposure and control of the atlantoaxial VA become necessary.
Calculation methods for advanced concept light water reactor lattices
International Nuclear Information System (INIS)
Carmona, S.
1986-01-01
In the last few years s several advanced concepts for fuel rod lattices have been studied. Improved fuel utilization is one of the major aims in the development of new fuel rod designs and lattice modifications. By these changes s better performance in fuel economics s fuel burnup and material endurance can be achieved in the frame of the well-known basic Light Water Reactor technology. Among the new concepts involved in these studies that have attracted serious attention are lattices consisting of arrays of annular rods duplex pellet rods or tight multicells. These new designs of fuel rods and lattices present several computational problems. The treatment of resonance shielded cross sections is a crucial point in the analyses of these advanced concepts . The purpose of this study was to assess adequate approximation methods for calculating as accurately as possible, resonance shielding for these new lattices. Although detailed and exact computational methods for the evaluation of the resonance shielding in these lattices are possible, they are quite inefficient when used in lattice codes. The computer time and memory required for this kind of computations are too large to be used in an acceptable routine manner. In order to over- come these limitations and to make the analyses possible with reasonable use of computer resources s approximation methods are necessary. Usual approximation methods, for the resonance energy regions used in routine lattice computer codes, can not adequately handle the evaluation of these new fuel rod lattices. The main contribution of the present work to advanced lattice concepts is the development of an equivalence principle for the calculation of resonance shielding in the annular fuel pellet zone of duplex pellets; the duplex pellet in this treatment consists of two fuel zones with the same absorber isotope in both regions. In the transition from a single duplex rod to an infinite array of this kind of fuel rods, the similarity of the
Lattice-induced nonadiabatic frequency shifts in optical lattice clocks
International Nuclear Information System (INIS)
Beloy, K.
2010-01-01
We consider the frequency shift in optical lattice clocks which arises from the coupling of the electronic motion to the atomic motion within the lattice. For the simplest of three-dimensional lattice geometries this coupling is shown to affect only clocks based on blue-detuned lattices. We have estimated the size of this shift for the prospective strontium lattice clock operating at the 390-nm blue-detuned magic wavelength. The resulting fractional frequency shift is found to be on the order of 10 -18 and is largely overshadowed by the electric quadrupole shift. For lattice clocks based on more complex geometries or other atomic systems, this shift could potentially be a limiting factor in clock accuracy.
Lattice topology dictates photon statistics.
Kondakci, H Esat; Abouraddy, Ayman F; Saleh, Bahaa E A
2017-08-21
Propagation of coherent light through a disordered network is accompanied by randomization and possible conversion into thermal light. Here, we show that network topology plays a decisive role in determining the statistics of the emerging field if the underlying lattice is endowed with chiral symmetry. In such lattices, eigenmode pairs come in skew-symmetric pairs with oppositely signed eigenvalues. By examining one-dimensional arrays of randomly coupled waveguides arranged on linear and ring topologies, we are led to a remarkable prediction: the field circularity and the photon statistics in ring lattices are dictated by its parity while the same quantities are insensitive to the parity of a linear lattice. For a ring lattice, adding or subtracting a single lattice site can switch the photon statistics from super-thermal to sub-thermal, or vice versa. This behavior is understood by examining the real and imaginary fields on a lattice exhibiting chiral symmetry, which form two strands that interleave along the lattice sites. These strands can be fully braided around an even-sited ring lattice thereby producing super-thermal photon statistics, while an odd-sited lattice is incommensurate with such an arrangement and the statistics become sub-thermal.
Dynamics of an impurity in a one-dimensional lattice
International Nuclear Information System (INIS)
Massel, F; Kantian, A; Giamarchi, T; Daley, A J; Törmä, P
2013-01-01
We study the non-equilibrium dynamics of an impurity in a harmonic trap that is kicked with a well-defined quasi-momentum, and interacts with a bath of free fermions or interacting bosons in a one-dimensional lattice configuration. Using numerical and analytical techniques we investigate the full dynamics beyond linear response, which allows us to quantitatively characterize states of the impurity in the bath for different parameter regimes. These vary from a tightly bound molecular state in a strongly interacting limit to a polaron (dressed impurity) and a free particle for weak interactions, with composite behaviour in the intermediate regime. These dynamics and different parameter regimes should be readily realizable in systems of cold atoms in optical lattices. (paper)
Directory of Open Access Journals (Sweden)
Lan Wang
Full Text Available Much information could be processed unconsciously. However, there is no direct evidence on whether perceptual grouping could occur without awareness. To answer this question, we investigated whether a Kanizsa triangle (an example of perceptual grouping is processed differently from stimuli with the same local components but are ungrouped or weakly grouped. Specifically, using a suppression time paradigm we tested whether a Kanizsa triangle would emerge from interocular continuous flash suppression sooner than control stimuli. Results show a significant advantage of the Kanizsa triangle: the Kanizsa triangle emerged from suppression noise significantly faster than the control stimulus with the local Pacmen randomly rotated (t(9 = -2.78, p = 0.02; and also faster than the control stimulus with all Pacmen rotated 180° (t(11 = -3.20, p<0.01. Additional results demonstrated that the advantage of the grouped Kanizsa triangle could not be accounted for by the faster detection speed at the conscious level for the Kanizsa figures on a dynamic noise background. Our results indicate that certain properties supporting perceptual grouping could be processed in the absence of awareness.
Sex Determination Using Inion-Opistocranium-Asterion (IOA Triangle in Nigerians’ Skulls
Directory of Open Access Journals (Sweden)
C. N. Orish
2014-01-01
Full Text Available Background. Determination of sex is an important concern to the forensic anthropologists as it is critical for individual identification. This study has investigated the existence of sexual dimorphism in the dimensions and the area of the IOA triangle. Methods. A total of 100 adult dry skulls, (78 males; 22 females from departments of anatomy in Nigerian universities were used for this study. Automatic digital calliper was used for the measurement. Coefficient of variation, correlation, linear regression, percentiles, and sexual dimorphism ratio were computed from the IOA triangle measurements. The IOA triangle area was compared between sexes. Results. The male parameters were significantly (P<0.05 higher than female parameters. The left opistocranium-asterion length was 71.09±0.56 and 61.68±3.35 mm and the right opistocranium-asterion length was 69.73±0.49 and 60.92±2.10 mm for male and female, respectively. A total area of IOA triangle of 1938.88 mm2 and 1305.68 mm2 for male and female, respectively, was calculated. The left IOA indices were 46.42% and 37.40% in males and females, respectively, while the right IOA indices for males and females were 47.19% and 38.87%, respectively. Conclusion. The anthropometry of inion-opistocranium-asterion IOA triangle can be a guide in gender determination of unknown individuals.
Visual Search for Wines with a Triangle on the Label in a Virtual Store
Directory of Open Access Journals (Sweden)
Hui Zhao
2017-12-01
Full Text Available Two experiments were conducted in a virtual reality (VR environment in order to investigate participants’ in-store visual search for bottles of wines displaying a prominent triangular shape on their label. The experimental task involved virtually moving along a wine aisle in a virtual supermarket while searching for the wine bottle on the shelf that had a different triangle on its label from the other bottles. The results of Experiment 1 revealed that the participants identified the bottle with a downward-pointing triangle on its label more rapidly than when looking for an upward-pointing triangle on the label instead. This finding replicates the downward-pointing triangle superiority (DPTS effect, though the magnitude of this effect was more pronounced in the first as compared to the second half of the experiment, suggesting a modulating role of practice. The results of Experiment 2 revealed that the DPTS effect was also modulated by the location of the target on the shelf. Interestingly, however, the results of a follow-up survey demonstrate that the orientation of the triangle did not influence the participants’ evaluation of the wine bottles. Taken together, these findings reveal how in-store the attention of consumers might be influenced by the design elements in product packaging. These results therefore suggest that shopping in a virtual supermarket might offer a practical means of assessing the shelf standout of product packaging, which has important implications for food marketing.
Visual Search for Wines with a Triangle on the Label in a Virtual Store.
Zhao, Hui; Huang, Fuxing; Spence, Charles; Wan, Xiaoang
2017-01-01
Two experiments were conducted in a virtual reality (VR) environment in order to investigate participants' in-store visual search for bottles of wines displaying a prominent triangular shape on their label. The experimental task involved virtually moving along a wine aisle in a virtual supermarket while searching for the wine bottle on the shelf that had a different triangle on its label from the other bottles. The results of Experiment 1 revealed that the participants identified the bottle with a downward-pointing triangle on its label more rapidly than when looking for an upward-pointing triangle on the label instead. This finding replicates the downward-pointing triangle superiority (DPTS) effect, though the magnitude of this effect was more pronounced in the first as compared to the second half of the experiment, suggesting a modulating role of practice. The results of Experiment 2 revealed that the DPTS effect was also modulated by the location of the target on the shelf. Interestingly, however, the results of a follow-up survey demonstrate that the orientation of the triangle did not influence the participants' evaluation of the wine bottles. Taken together, these findings reveal how in-store the attention of consumers might be influenced by the design elements in product packaging. These results therefore suggest that shopping in a virtual supermarket might offer a practical means of assessing the shelf standout of product packaging, which has important implications for food marketing.
International Nuclear Information System (INIS)
Kilcup, G.
1986-01-01
A progress report on a lattice project at Los Alamos is presented. The projects are basically of two sorts: approaching the continuum (determination of MCRG flows under the blocking transformation, and beta-function along Wilson and improved action lines); and arriving at the continuum (hadron spectrum, coupling constants, and matrix elements). Since the ultimate goal is to determine matrix elements for which chiral symmetry is very relevant, the authors choose the formalism whose chiral properties are easier to understand, i.e., staggered fermions
Lattice of quantum predictions
Drieschner, Michael
1993-10-01
What is the structure of reality? Physics is supposed to answer this question, but a purely empiristic view is not sufficient to explain its ability to do so. Quantum mechanics has forced us to think more deeply about what a physical theory is. There are preconditions every physical theory must fulfill. It has to contain, e.g., rules for empirically testable predictions. Those preconditions give physics a structure that is “a priori” in the Kantian sense. An example is given how the lattice structure of quantum mechanics can be understood along these lines.
Lattice Vibrations in Chlorobenzenes:
DEFF Research Database (Denmark)
Reynolds, P. A.; Kjems, Jørgen; White, J. W.
1974-01-01
Lattice vibrational dispersion curves for the ``intermolecular'' modes in the triclinic, one molecule per unit cell β phase of p‐C6D4Cl2 and p‐C6H4Cl2 have been obtained by inelastic neutron scattering. The deuterated sample was investigated at 295 and at 90°K and a linear extrapolation to 0°K...... was applied in order to correct for anharmonic effects. Calculations based on the atom‐atom model for van der Waals' interaction and on general potential parameters for the aromatic compounds agree reasonably well with the experimental observations. There is no substantial improvement in fit obtained either...
Diamond lattice Heisenberg antiferromagnet
Oitmaa, J.
2018-04-01
We investigate ground-state and high-temperature properties of the nearest-neighbour Heisenberg antiferromagnet on the three-dimensional diamond lattice, using series expansion methods. The ground-state energy and magnetization, as well as the magnon spectrum, are calculated and found to be in good agreement with first-order spin-wave theory, with a quantum renormalization factor of about 1.13. High-temperature series are derived for the free energy, and physical and staggered susceptibilities for spin S = 1/2, 1 and 3/2, and analysed to obtain the corresponding Curie and Néel temperatures.
Lattice cell burnup calculation
International Nuclear Information System (INIS)
Pop-Jordanov, J.
1977-01-01
Accurate burnup prediction is a key item for design and operation of a power reactor. It should supply information on isotopic changes at each point in the reactor core and the consequences of these changes on the reactivity, power distribution, kinetic characters, control rod patterns, fuel cycles and operating strategy. A basic stage in the burnup prediction is the lattice cell burnup calculation. This series of lectures attempts to give a review of the general principles and calculational methods developed and applied in this area of burnup physics
Crisafulli, M.; Martinelli, G.; Sachrajda, Christopher T.; Crisafulli, M; Gimenez, V; Martinelli, G; Sachrajda, C T
1994-01-01
We present the first lattice calculation of the B-meson binding energy \\labar and of the kinetic energy \\lambda_1/2 m_Q of the heavy-quark inside the pseudoscalar B-meson. In order to cancel the ambiguities due to the ultraviolet renormalons present in the operator matrix elements, this calculation has required the non-perturbative subtraction of the power divergences present in the Lagrangian operator \\energy and in the kinetic energy operator \\kkinetic. The non-perturbative renormalization of the relevant operators has been implemented by imposing suitable renormalization conditions on quark matrix elements in the Landau gauge.
International Nuclear Information System (INIS)
Vidovsky, I.; Kereszturi, A.
1991-11-01
The results of experiments and calculations on Gd lattices are presented, and a comparison of experimental and calculational data is given. This latter can be divided into four groups. The first belongs to the comparison of criticality parameters, the second group is related with the comparison of 2D distributions, the third one relates the comparison of intra-macrocell distributions, whereas the fourth group is devoted for the comparison of spectral parameters. For comparison, the computer code RFIT based on strict statistical criteria has been used. The calculated and measured results agree, in most cases, sufficiently. (R.P.) 11 refs.; 13 figs.; 9 tabs
Permanent magnetic lattices for ultracold atoms and quantum degenerate gases
International Nuclear Information System (INIS)
Ghanbari, Saeed; Kieu, Tien D; Sidorov, Andrei; Hannaford, Peter
2006-01-01
We propose the use of periodic arrays of permanent magnetic films for producing magnetic lattices of microtraps for confining, manipulating and controlling small clouds of ultracold atoms and quantum degenerate gases. Using analytical expressions and numerical calculations we show that periodic arrays of magnetic films can produce one-dimensional (1D) and two-dimensional (2D) magnetic lattices with non-zero potential minima, allowing ultracold atoms to be trapped without losses due to spin flips. In particular, we show that two crossed layers of periodic arrays of parallel rectangular magnets plus bias fields, or a single layer of periodic arrays of square-shaped magnets with three different thicknesses plus bias fields, can produce 2D magnetic lattices of microtraps having non-zero potential minima and controllable trap depth. For arrays with micron-scale periodicity, the magnetic microtraps can have very large trap depths (∼0.5 mK for the realistic parameters chosen for the 2D lattice) and very tight confinement
Three-dimensional measurement of a tightly focused laser beam
Directory of Open Access Journals (Sweden)
Xiangsheng Xie
2013-02-01
Full Text Available The spatial structure of a tightly focused light field is measured with a double knife-edge scanning method. The measurement method is based on the use of a high-quality double knife-edge fabricated from a right-angled silicon fragment mounted on a photodetector. The reconstruction of the three-dimensional structures of tightly focused spots is carried out with both uniform and partially obstructed linearly polarized incident light beams. The optical field distribution is found to deviate substantially from the input beam profile in the tightly focused region, which is in good agreement with the results of numerical simulations.
Triangular and honeycomb lattices bond-diluted Ising ferromagnet: critical frontier
International Nuclear Information System (INIS)
Magalhaes, A.C.N. de; Schwaccheim, G.; Tsallis, C.
1982-01-01
Within a real space renormalization group framework (12 different procedures, all of them using star-triangle and duality-type transformations) accurate approximations for the critical frontiers associated with the quenched bond-diluted first-neighbour spin- 1 / 2 Ising ferromagnet on triangular and honeycomb lattices are calculated. All of them provide, in both pure bond percolation and pure Ising limits, the exact critical points and exact or almost exact derivatives in the p-t space (p is the bond independent occupancy probability and t tanh J/k(sub B)T). The best numerical proposals lead to the exact derivative in the pure percolation limit (p = p(sub c)) and, in what concerns the pure Ising limit (p = 1) derivative, to a 0.15% error for the triangular lattice and to a 0.96% error for the honeycomb one; in the intermediate region (p(sub c) [pt
Lattice Transparency of Graphene.
Chae, Sieun; Jang, Seunghun; Choi, Won Jin; Kim, Youn Sang; Chang, Hyunju; Lee, Tae Il; Lee, Jeong-O
2017-03-08
Here, we demonstrated the transparency of graphene to the atomic arrangement of a substrate surface, i.e., the "lattice transparency" of graphene, by using hydrothermally grown ZnO nanorods as a model system. The growth behaviors of ZnO nanocrystals on graphene-coated and uncoated substrates with various crystal structures were investigated. The atomic arrangements of the nucleating ZnO nanocrystals exhibited a close match with those of the respective substrates despite the substrates being bound to the other side of the graphene. By using first-principles calculations based on density functional theory, we confirmed the energetic favorability of the nucleating phase following the atomic arrangement of the substrate even with the graphene layer present in between. In addition to transmitting information about the atomic lattice of the substrate, graphene also protected its surface. This dual role enabled the hydrothermal growth of ZnO nanorods on a Cu substrate, which otherwise dissolved in the reaction conditions when graphene was absent.
International Nuclear Information System (INIS)
Yang Jue; Oka, Yoshiaki; Ishiwatari, Yuki; Liu Jie; Yoo, Jaewoon
2007-01-01
Heat transfer in upward flows of supercritical water in circular tubes and in tight fuel rod bundles is numerically investigated by using the commercial CFD code STAR-CD 3.24. The objective is to have more understandings about the phenomena happening in supercritical water and for designs of supercritical water cooled reactors. Some turbulence models are selected to carry out numerical simulations and the results are compared with experimental data and other correlations to find suitable models to predict heat transfer in supercritical water. The comparisons are not only in the low bulk temperature region, but also in the high bulk temperature region. The two-layer model (Hassid and Poreh) gives a better prediction to the heat transfer than other models, and the standard k-ε high Re model with the standard wall function also shows an acceptable predicting capability. Three-dimensional simulations are carried out in sub-channels of tight square lattice and triangular lattice fuel rod bundles at supercritical pressure. Results show that there is a strong non-uniformity of the circumferential distribution of the cladding surface temperature, in the square lattice bundle with a small pitch-to-diameter ratio (P/D). However, it does not occur in the triangular lattice bundle with a small P/D. It is found that this phenomenon is caused by the large non-uniformity of the flow area in the cross-section of sub-channels. Some improved designs are numerically studied and proved to be effective to avoid the large circumferential temperature gradient at the cladding surface
Introduction to lattice gauge theories
International Nuclear Information System (INIS)
La Cock, P.
1988-03-01
A general introduction to Lattice Gauge Theory (LGT) is given. The theory is discussed from first principles to facilitate an understanding of the techniques used in LGT. These include lattice formalism, gauge invariance, fermions on the lattice, group theory and integration, strong coupling methods and mean field techniques. A review of quantum chromodynamics on the lattice at finite temperature and density is also given. Monte Carlo results and analytical methods are discussed. An attempt has been made to include most relevant data up to the end of 1987, and to update some earlier reviews existing on the subject. 224 refs., 33 figs., 14 tabs
Hadron structure from lattice QCD
International Nuclear Information System (INIS)
Schaefer, Andreas
2008-01-01
Some elements and current developments of lattice QCD are reviewed, with special emphasis on hadron structure observables. In principle, high precision experimental and lattice data provide nowadays a very detailled picture of the internal structure of hadrons. However, to relate both, a very good controle of perturbative QCD is needed in many cases. Finally chiral perturbation theory is extremely helpful to boost the precision of lattice calculations. The mutual need and benefit of all four elements: experiment, lattice QCD, perturbative QCD and chiral perturbation theory is the main topic of this review
Lattice formulations of reggeon interactions
International Nuclear Information System (INIS)
Brower, R.C.; Ellis, J.; Savit, R.; Zinn-Justin, J.
1976-01-01
A class of lattice analogues to reggeon field theory is examined. First the transition from a continuum to a lattice field theory is discussed, emphasizing the necessity of a Wick rotation and the consideration of symmetry properties. Next the theory is transformed to a discrete system with two spins at each lattice site, and the problems of the triple-reggeon interaction and the reggeon energy gap are discussed. It is pointed out that transferring the theory from the continuum to a lattice necesarily introduces new relevant operators not normally present in reggeon field theory. (Auth.)
Socolovsky, Eduardo A.; Bushnell, Dennis M. (Technical Monitor)
2002-01-01
The cosine or correlation measures of similarity used to cluster high dimensional data are interpreted as projections, and the orthogonal components are used to define a complementary dissimilarity measure to form a similarity-dissimilarity measure pair. Using a geometrical approach, a number of properties of this pair is established. This approach is also extended to general inner-product spaces of any dimension. These properties include the triangle inequality for the defined dissimilarity measure, error estimates for the triangle inequality and bounds on both measures that can be obtained with a few floating-point operations from previously computed values of the measures. The bounds and error estimates for the similarity and dissimilarity measures can be used to reduce the computational complexity of clustering algorithms and enhance their scalability, and the triangle inequality allows the design of clustering algorithms for high dimensional distributed data.
Performance Comparison Of Triangle Antenna of 60 GHz for 5G Wireless Communication Network
Directory of Open Access Journals (Sweden)
Aishah A.S.
2017-01-01
Full Text Available In this paper microstrip triangle with slot antenna for 5G wireless communication network are proposed. The microstip triangle antenna is design and operating 60 GHz milimeter-wave frequency band and it's suitable for 5G wireless communication. The substrates are chosen in the design, which are RogerRT5880 with copper thickness 0.035 mm to analyze their effect toward milimeter-wave performance on the designed. The designed and analysis is performed by using CST Microwave Studio. The lowest return loss of the antenna is -24.75dB which is triangle with slot and the maximum gain obtained is 6.82 db at the 59.68GHz for this antenna. The antenna is considering the gain, return loss and size, the microstrip antenna can be a suitable candidate for the 5G wireless application for short range high speed communication.
Is this child sick? Usefulness of the Pediatric Assessment Triangle in emergency settings
Directory of Open Access Journals (Sweden)
Ana Fernandez
Full Text Available Abstract Objective: The Pediatric Assessment Triangle is a rapid assessment tool that uses only visual and auditory clues, requires no equipment, and takes 30-60 s to perform. It's being used internationally in different emergency settings, but few studies have assessed its performance. The aim of this narrative biomedical review is to summarize the literature available regarding the usefulness of the Pediatric Assessment Triangle in clinical practice. Sources: The authors carried out a non-systematic review in the PubMed®, MEDLINE®, and EMBASE® databases, searching for articles published between 1999-2016 using the keywords “pediatric assessment triangle,” “pediatric triage,” “pediatric assessment tools,” and “pediatric emergency department.” Summary of the findings: The Pediatric Assessment Triangle has demonstrated itself to be useful to assess sick children in the prehospital setting and make transport decisions. It has been incorporated, as an essential instrument for assessing sick children, into different life support courses, although little has been written about the effectiveness of teaching it. Little has been published about the performance of this tool in the initial evaluation in the emergency department. In the emergency department, the Pediatric Assessment Triangle is useful to identify the children at triage who require more urgent care. Recent studies have assessed and proved its efficacy to also identify those patients having more serious health conditions who are eventually admitted to the hospital. Conclusions: The Pediatric Assessment Triangle is quickly spreading internationally and its clinical applicability is very promising. Nevertheless, it is imperative to promote research for clinical validation, especially for clinical use by emergency pediatricians and physicians.
A clear map of the lower cranial nerves at the superior carotid triangle.
Cavalcanti, Daniel D; Garcia-Gonzalez, Ulises; Agrawal, Abhishek; Tavares, Paulo L M S; Spetzler, Robert F; Preul, Mark C
2010-07-01
The lower cranial nerves must be identified to avoid iatrogenic injury during skull base and high cervical approaches. Prompt recognition of these structures using basic landmarks could reduce surgical time and morbidity. The anterior triangle of the neck was dissected in 30 cadaveric head sides. The most superficial segments of the glossopharyngeal, vagus and its superior laryngeal nerves, accessory, and hypoglossal nerves were exposed and designated into smaller anatomic triangles. The midpoint of each nerve segment inside the triangles was correlated to the angle of the mandible (AM), mastoid tip (MT), and bifurcation of the common carotid artery. A triangle bounded by the styloglossus muscle, external carotid artery, and facial artery housed the glossopharyngeal nerve. This nerve segment was 0.06 ± 0.71 cm posterior to the AM and 2.50 ± 0.59 cm inferior to the MT. The vagus nerve ran inside the carotid sheath posterior to internal carotid artery and common carotid artery bifurcation in 48.3% of specimens. A triangle formed by the posterior belly of digastric muscle, sternocleidomastoid muscle, and internal jugular vein housed the accessory nerve, 1.90 ± 0.60 cm posterior to the AM and 2.30 ± 0.57 cm inferior to the MT. A triangle outlined by the posterior belly of digastric muscle, internal jugular vein, and common facial vein housed the hypoglossal nerve, which was 0.82 ± 0.84 cm posterior to the AM and 3.64 ± 0.70 cm inferior to the MT. Comprehensible landmarks can be defined to help expose the lower cranial nerves to avoid injury to this complex region. Copyright © 2010 Elsevier Inc. All rights reserved.
Convection-diffusion lattice Boltzmann scheme for irregular lattices
Sman, van der R.G.M.; Ernst, M.H.
2000-01-01
In this paper, a lattice Boltzmann (LB) scheme for convection diffusion on irregular lattices is presented, which is free of any interpolation or coarse graining step. The scheme is derived using the axioma that the velocity moments of the equilibrium distribution equal those of the
Elimination of spurious lattice fermion solutions and noncompact lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Lee, T.D.
1997-09-22
It is well known that the Dirac equation on a discrete hyper-cubic lattice in D dimension has 2{sup D} degenerate solutions. The usual method of removing these spurious solutions encounters difficulties with chiral symmetry when the lattice spacing l {ne} 0, as exemplified by the persistent problem of the pion mass. On the other hand, we recall that in any crystal in nature, all the electrons do move in a lattice and satisfy the Dirac equation; yet there is not a single physical result that has ever been entangled with a spurious fermion solution. Therefore it should not be difficult to eliminate these unphysical elements. On a discrete lattice, particle hop from point to point, whereas in a real crystal the lattice structure in embedded in a continuum and electrons move continuously from lattice cell to lattice cell. In a discrete system, the lattice functions are defined only on individual points (or links as in the case of gauge fields). However, in a crystal the electron state vector is represented by the Bloch wave functions which are continuous functions in {rvec {gamma}}, and herein lies one of the essential differences.
International Nuclear Information System (INIS)
Bhattacharya, Sayak; Shah, Kushal
2015-01-01
The analytical dispersion relation of spoof surface plasmon (SSP) is known only in the low-frequency limit and thus cannot be used to describe various practically important characteristics of SSP in the high-frequency limit (such as multimodal nature, anisotropic propagation, self-collimation). In this article, we consider a square lattice of holes made on a perfect electric conductor and derive a closed form expression of the SSP dispersion relation in the high-frequency limit using a tight binding model. Instead of using prior knowledge of the band diagram along the entire first Brillouin zone (BZ) edge, we analytically determine the hopping parameters by using the eigenfrequencies only at the three high-symmetry points of the square lattice. Using this dispersion relation, we derive an expression for the self-collimation frequency of SSP. We show that this analytical formulation is also applicable to dielectric photonic crystals and can be used to predict the frequencies corresponding to centimetre-scale supercollimation and second band self-collimation in these structures. Finally, we show that our analytical results are in agreement with the simulation results for both SSP and photonic crystals. (paper)
On tight multiparty Bell inequalities for many settings
Zukowski, Marek
2006-01-01
A derivation method is given which leads to a series of tight Bell inequalities for experiments involving N parties, with binary observables, and three possible local settings. The approach can be generalized to more settings. Ramifications are presented.
Quality of surface-water supplies in the Triangle area of North Carolina, water year 2008
Giorgino, M.J.; Rasmussen, R.B.; Pfeifle, C.A.
2012-01-01
Surface-water supplies are important sources of drinking water for residents in the Triangle area of North Carolina, which is located within the upper Cape Fear and Neuse River Basins. Since 1988, the U.S. Geological Survey and a consortium of governments have tracked water-quality conditions and trends in several of the area's water-supply lakes and streams. This report summarizes data collected through this cooperative effort, known as the Triangle Area Water Supply Monitoring Project, during October 2007 through September 2008. Major findings for this period include:
New solutions of the star-triangle relation with discrete and continuous spin variables
Kels, Andrew P.
2015-01-01
A new solution to the star-triangle relation is given, for an Ising type model that involves interacting spins, that contain integer and real valued components. Boltzmann weights of the model are given in terms of the lens elliptic-gamma function, and are based on Yamazaki's recently obtained solution of the star-star relation. The star-triangle given here, implies Seiberg duality for the $4\\!-\\!d$ $\\mathcal{N}=1$ $S_1\\times S_3/\\mathbb{Z}_r$ index of the $SU(2)$ quiver gauge theory, and the ...
On the chromatic number of triangle-free graphs of large minimum degree
DEFF Research Database (Denmark)
Thomassen, Carsten
2002-01-01
We prove that, for each. fixed real number c > 1/3, the triangle-free graphs of minimum degree at least cn (where n is the number of vertices) have bounded chromatic number. This problem was raised by Erdos and Simonovits in 1973 who pointed out that there is no such result for c <1/3.......We prove that, for each. fixed real number c > 1/3, the triangle-free graphs of minimum degree at least cn (where n is the number of vertices) have bounded chromatic number. This problem was raised by Erdos and Simonovits in 1973 who pointed out that there is no such result for c
Western tight gas sands advanced logging workshop proceedings
Energy Technology Data Exchange (ETDEWEB)
Jennings, J B; Carroll, Jr, H B [eds.
1982-04-01
An advanced logging research program is one major aspect of the Western Tight Sands Program. Purpose of this workshop is to help BETC define critical logging needs for tight gas sands and to allow free interchange of ideas on all aspects of the current logging research program. Sixteen papers and abstracts are included together with discussions. Separate abstracts have been prepared for the 12 papers. (DLC)
Hamstring tightness and Scheuermann's disease a pilot study.
Fisk, J W; Baigent, M L
1981-06-01
The lateral radiographs of the dorsal spines of 20 patients presenting with mainly low back pain are studied. These patients had clinically evident loss of flexion in the low dorsal spine and very tight hamstring muscles. 85% of them showed definite evidence of previous Scheuermann's Disease. The possibility that tight hamstrings may be an important factor in the aetiology of this disease is discussed, and a further large scale study is proposed.
Contraption and Prediction of Exhalation Tight Brownstone in Exhalation Cistern
XhingZhiwang, -; Xuchao, -
2012-01-01
The reservoir connate water saturation is high and gas wells generally produce water which seriously affects the productivity of gas wells in Xujiahe tight sandstone gas reservoirs in Sichuan Basin. Take the sixth formation for example, there are 39 wells producing water unequally in the 42 commissioning wells, and the excessive water production leads to the production of the gas well declining rapidly. Studying of the mechanism of water production in tight sandstone gas reservoirs and predic...
Regulation of Tight Junctions in Upper Airway Epithelium
Directory of Open Access Journals (Sweden)
Takashi Kojima
2013-01-01
Full Text Available The mucosal barrier of the upper respiratory tract including the nasal cavity, which is the first site of exposure to inhaled antigens, plays an important role in host defense in terms of innate immunity and is regulated in large part by tight junctions of epithelial cells. Tight junction molecules are expressed in both M cells and dendritic cells as well as epithelial cells of upper airway. Various antigens are sampled, transported, and released to lymphocytes through the cells in nasal mucosa while they maintain the integrity of the barrier. Expression of tight junction molecules and the barrier function in normal human nasal epithelial cells (HNECs are affected by various stimuli including growth factor, TLR ligand, and cytokine. In addition, epithelial-derived thymic stromal lymphopoietin (TSLP, which is a master switch for allergic inflammatory diseases including allergic rhinitis, enhances the barrier function together with an increase of tight junction molecules in HNECs. Furthermore, respiratory syncytial virus infection in HNECs in vitro induces expression of tight junction molecules and the barrier function together with proinflammatory cytokine release. This paper summarizes the recent progress in our understanding of the regulation of tight junctions in the upper airway epithelium under normal, allergic, and RSV-infected conditions.
Lattice quantum chromodynamics
International Nuclear Information System (INIS)
Hassenfratz, P.
1983-01-01
It is generally accepted that relativistic field theory is relevant in high energy physics. It is also recognized that even in QCD, which is asymptotically free, the scope of perturbation theory is very limited. Despite the tremendous theoretical and experimental effort to study scaling, scaling violations, e + e - , lepton pair creation, jets, etc., the answer to the question whether and to what extent is QCD the theory of strong interactions is vague. At present-day energies it is difficult to disentangle perturbative and non-perturbative effects. The author states that QCD must be understood and that quantitative non-perturbative methods are needed. He states that the lattice formulation of field theories is a promising approach to meeting this need and discusses the formulation in detail in this paper
Review of lattice results concerning low-energy particle physics
Energy Technology Data Exchange (ETDEWEB)
Aoki, S. [Kyoto Univ. (Japan). Yukawa Inst. for Theoretical Physics; Aoki, Y. [Nagoya Univ. (Japan). Kobayashi-Maskawa Inst. for the Origin of Particles and the Universe; Brookhaven National Laboratory, Upton, NY (United States). RIKEN BNL Research Center; Becirevic, D. [Univ. Paris-Saclay, Orsay (France). CNRS; Collaboration: FLAG Working Group; and others
2016-07-15
We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form factor f{sub +}(0), arising in the semileptonic K→π transition at zero momentum transfer, as well as the decay constant ratio f{sub K}/f{sub π} and its consequences for the CKM matrix elements V{sub us} and V{sub ud}. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2){sub L} x SU(2){sub R} and SU(3){sub L} x SU(3){sub R} Chiral Perturbation Theory. We review the determination of the B{sub K} parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for m{sub c} and m{sub b} (also new compared to the previous review), as well as those for D- and B-meson decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant α{sub s}.
Review of lattice results concerning low-energy particle physics
Energy Technology Data Exchange (ETDEWEB)
Aoki, S. [Kyoto University, Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto (Japan); Aoki, Y. [Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya (Japan); Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States); High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Becirevic, D. [Universite Paris-Sud, Universite Paris-Saclay, Laboratoire de Physique Theorique (UMR8627), CNRS, Orsay (France); Bernard, C. [Washington University, Department of Physics, Saint Louis, MO (United States); Blum, T. [Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States); University of Connecticut, Physics Department, Storrs, CT (United States); Colangelo, G.; Leutwyler, H.; Wenger, U. [Universitaet Bern, Albert Einstein Center for Fundamental Physics, Institut fuer Theoretische Physik, Bern (Switzerland); Della Morte, M. [University of Southern Denmark, CP3-Origins and Danish IAS, Odense M (Denmark); IFIC (CSIC), Paterna (Spain); Dimopoulos, P. [Centro Fermi-Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi Compendio del Viminale, Rome (Italy); Universita di Roma Tor Vergata, c/o Dipartimento di Fisica, Rome (Italy); Duerr, S. [University of Wuppertal, Wuppertal (Germany); Juelich Supercomputing Center, Forschungszentrum Juelich, Juelich (Germany); Fukaya, H.; Onogi, T. [Osaka University, Department of Physics, Toyonaka, Osaka (Japan); Golterman, M. [San Francisco State University, Department of Physics and Astronomy, San Francisco, CA (United States); Gottlieb, Steven; Lunghi, E. [Indiana University, Department of Physics, Bloomington, IN (United States); Hashimoto, S.; Kaneko, T. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); The Graduate University for Advanced Studies (Sokendai), School of High Energy Accelerator Science, Tsukuba (Japan); Heller, U.M. [American Physical Society (APS), Ridge, NY (United States); Horsley, R. [University of Edinburgh, Higgs Centre for Theoretical Physics, School of Physics and Astronomy, Edinburgh (United Kingdom); Juettner, A.; Sachrajda, C.T. [University of Southampton, School of Physics and Astronomy, Southampton (United Kingdom); Lellouch, L. [CNRS, Aix-Marseille Universite, Universite de Toulon, Centre de Physique Theorique, UMR 7332, Marseille (France); Lin, C.J.D. [CNRS, Aix-Marseille Universite, Universite de Toulon, Centre de Physique Theorique, UMR 7332, Marseille (France); National Chiao-Tung University, Institute of Physics, Hsinchu (China); Lubicz, V. [Universita Roma Tre, Dipartimento di Matematica e Fisica, Rome (Italy); INFN, Sezione di Roma Tre, Rome (Italy); Mawhinney, R. [Columbia University, Physics Department, New York, NY (United States); Pena, C. [Universidad Autonoma de Madrid, Departamento de Fisica Teorica, Instituto de Fisica Teorica UAM/CSIC, Madrid (Spain); Sharpe, S.R. [University of Washington, Physics Department, Seattle, WA (United States); Simula, S. [INFN, Sezione di Roma Tre, Rome (Italy); Sommer, R. [DESY, John von Neumann Institute for Computing (NIC), Zeuthen (Germany); Vladikas, A. [Universita di Roma ' ' Tor Vergata' ' , Dipartimento di Fisica, Rome (Italy); INFN, Rome (Italy); Wittig, H. [University of Mainz, PRISMA Cluster of Excellence, Institut fuer Kernphysik and Helmholtz Institute Mainz, Mainz (Germany); Collaboration: Flavour Lattice Averaging Group (FLAG)
2017-02-15
We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor f{sub +}(0), arising in the semileptonic K → π transition at zero momentum transfer, as well as the decay constant ratio f{sub K}/f{sub π} and its consequences for the CKM matrix elements V{sub us} and V{sub ud}. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2){sub L} x SU(2){sub R} and SU(3){sub L} x SU(3){sub R} Chiral Perturbation Theory. We review the determination of the B{sub K} parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for m{sub c} and m{sub b} (also new compared to the previous review), as well as those for D- and B-meson-decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant α{sub s}. (orig.)
Geometry of lattice field theory
International Nuclear Information System (INIS)
Honan, T.J.
1986-01-01
Using some tools of algebraic topology, a general formalism for lattice field theory is presented. The lattice is taken to be a simplicial complex that is also a manifold and is referred to as a simplicial manifold. The fields on this lattice are cochains, that are called lattice forms to emphasize the connections with differential forms in the continuum. This connection provides a new bridge between lattice and continuum field theory. A metric can be put onto this simplicial manifold by assigning lengths to every link or I-simplex of the lattice. Regge calculus is a way of defining general relativity on this lattice. A geometric discussion of Regge calculus is presented. The Regge action, which is a discrete form of the Hilbert action, is derived from the Hilbert action using distribution valued forms. This is a new derivation that emphasizes the underlying geometry. Kramers-Wannier duality in statistical mechanics is discussed in this general setting. Nonlinear field theories, which include gauge theories and nonlinear sigma models are discussed in the continuum and then are put onto a lattice. The main new result here is the generalization to curved spacetime, which consists of making the theory compatible with Regge calculus
Homogenization theory in reactor lattices
International Nuclear Information System (INIS)
Benoist, P.
1986-02-01
The purpose of the theory of homogenization of reactor lattices is to determine, by the mean of transport theory, the constants of a homogeneous medium equivalent to a given lattice, which allows to treat the reactor as a whole by diffusion theory. In this note, the problem is presented by laying emphasis on simplicity, as far as possible [fr
Remarks on lattice gauge models
International Nuclear Information System (INIS)
Grosse, H.
1981-01-01
The author reports a study of the phase structure of lattice gauge models where one takes as a gauge group a non-abelian discrete subgroup of SU(3). In addition he comments on a lattice action proposed recently by Manton and observes that it violates a positivity property. (Auth.)
Remarks on lattice gauge models
International Nuclear Information System (INIS)
Grosse, H.
1981-01-01
The author reports on a study of the phase structure of lattice gauge models where one takes as a gauge group a non-abelian discrete subgroup of SU(3). In addition he comments on a lattice action proposed recently by Manton (1980) and observes that it violates a positivity property. (Auth.)
Lattices, supersymmetry and Kaehler fermions
International Nuclear Information System (INIS)
Scott, D.M.
1984-01-01
It is shown that a graded extension of the space group of a (generalised) simple cubic lattice exists in any space dimension, D. The fermionic variables which arise admit a Kaehlerian interpretation. Each graded space group is a subgroup of a graded extension of the appropriate Euclidean group, E(D). The relevance of this to the construction of lattice theories is discussed. (author)
Lattice polytopes in coding theory
Directory of Open Access Journals (Sweden)
Ivan Soprunov
2015-05-01
Full Text Available In this paper we discuss combinatorial questions about lattice polytopes motivated by recent results on minimum distance estimation for toric codes. We also include a new inductive bound for the minimum distance of generalized toric codes. As an application, we give new formulas for the minimum distance of generalized toric codes for special lattice point configurations.
The Effect of Internet-Based Education on Student Success in Teaching of 8th Grade Triangles Subject
Kaya, Deniz; Kesan, Cenk; Izgiol, Dilek
2013-01-01
In the study, it was researched the effect of internet-based application on student success. Internet-based application was used at the teaching of triangles subject which is included in 8th grade units of triangles and algebra. The study was carried out over the internet with a computer software program: Vitamin Program. The study was carried out…
DEFF Research Database (Denmark)
Bech, P; Fava, Maurizio; Trivedi, M H
2012-01-01
vs. buspirone in the acute therapy of major depression in the STAR*D study. The triangle provides a composite view in three domains of antidepressive activity, side effects, and quality of life. Method: Within the pharmacopsychometric triangle, the short six-item subscales of the Hamilton Depression...
Hofstadter's butterfly in a two-dimensional lattice consisting of two sublattices
International Nuclear Information System (INIS)
Vugalter, G A; Pastukhov, A S
2004-01-01
Harper's equations for simple and complex two-dimensional lattices subject to a magnetic field have been derived in the tight-binding approximation. In our derivation we do not neglect the influence of the magnetic field on the electron eigenfunctions and eigenvalues in isolated atoms. Using a variational procedure for finding eigenfunctions and eigenvalues, we have self-consistently obtained Hofstadter's butterflies. Even for a simple square lattice Hofstadter's butterfly differs from the butterfly obtained in the case in which the influence of the magnetic field on the electron eigenvalues and eigenfunctions in isolated atoms is not taken into account
Hofstadter's butterfly in a two-dimensional lattice consisting of two sublattices
Energy Technology Data Exchange (ETDEWEB)
Vugalter, G A; Pastukhov, A S [Department of Physics, Nizhny Novgorod State University, 23 Gagarin Avenue, Nizhny Novgorod 603950 (Russian Federation)
2004-06-04
Harper's equations for simple and complex two-dimensional lattices subject to a magnetic field have been derived in the tight-binding approximation. In our derivation we do not neglect the influence of the magnetic field on the electron eigenfunctions and eigenvalues in isolated atoms. Using a variational procedure for finding eigenfunctions and eigenvalues, we have self-consistently obtained Hofstadter's butterflies. Even for a simple square lattice Hofstadter's butterfly differs from the butterfly obtained in the case in which the influence of the magnetic field on the electron eigenvalues and eigenfunctions in isolated atoms is not taken into account.
Computing the writhe on lattices
International Nuclear Information System (INIS)
Laing, C; Sumners, D W
2006-01-01
Given a polygonal closed curve on a lattice or space group, we describe a method for computing the writhe of the curve as the average of weighted projected writhing numbers of the polygon in a few directions. These directions are determined by the lattice geometry, the weights are determined by areas of regions on the unit 2-sphere, and the regions are formed by the tangent indicatrix to the polygonal curve. We give a new formula for the writhe of polygons on the face centred cubic lattice and prove that the writhe of polygons on the body centred cubic lattice, the hexagonal simple lattice, and the diamond space group is always a rational number, and discuss applications to ring polymers
International Nuclear Information System (INIS)
Unesaki, Hironobu; Shiroya, Seiji; Kanda, Keiji; Cathalau, Stephane; Carre, Franck-Olivier; Aizawa, Otohiko; Takeda, Toshikazu
2000-01-01
Analysis of the benchmark problems on the void coefficient of mixed-oxide (MOX)-fueled tight-pitch cells has been performed using the Japanese SRAC code system with the JENDL-3.2 library and the French APOLLO-2 code with the CEA93 library based on JEF-2.2. The benchmark problems have been specified to investigate the physical phenomena occurring during the progressive voidage of MOX-fueled tight-pitch lattices, such as high conversion light water reactor lattices, and to evaluate the impact of nuclear data and calculational methods. Despite the most recently compiled nuclear data libraries and the sophisticated calculation schemes employed in both code systems, the k ∞ and void reactivity values obtained by the two code systems show considerable discrepancy especially in the highly voided state. The discrepancy of k ∞ values shows an obvious dependence on void fraction and also has been shown to be sensitive to the isotopic composition of plutonium. The observed discrepancies are analyzed by being decomposed into contributing isotopes and reactions and have been shown to be caused by a complicated balance of both negative and positive components, which are mainly attributable to differences in a limited number of isotopes including 239 Pu, 241 Pu, 16 O, and stainless steel
Lattice gas cellular automata and lattice Boltzmann models an introduction
Wolf-Gladrow, Dieter A
2000-01-01
Lattice-gas cellular automata (LGCA) and lattice Boltzmann models (LBM) are relatively new and promising methods for the numerical solution of nonlinear partial differential equations. The book provides an introduction for graduate students and researchers. Working knowledge of calculus is required and experience in PDEs and fluid dynamics is recommended. Some peculiarities of cellular automata are outlined in Chapter 2. The properties of various LGCA and special coding techniques are discussed in Chapter 3. Concepts from statistical mechanics (Chapter 4) provide the necessary theoretical background for LGCA and LBM. The properties of lattice Boltzmann models and a method for their construction are presented in Chapter 5.
The India-Pakistan-China strategic triangle and the role of nuclear weapons
International Nuclear Information System (INIS)
Chellaney, B.
2002-01-01
This paper presents the Asian landscape with its regional balances and imbalances and its changes after September 11 and subsequent events. The nuclear posture and the role of nuclear weapons inside the China-India-Pakistan triangle is analyzed with respect to the US non-proliferation policy and its expanding military presence over the Asian continent. (J.S.)
The India-Pakistan-China strategic triangle and the role of nuclear weapons
Energy Technology Data Exchange (ETDEWEB)
Chellaney, B
2002-07-01
This paper presents the Asian landscape with its regional balances and imbalances and its changes after September 11 and subsequent events. The nuclear posture and the role of nuclear weapons inside the China-India-Pakistan triangle is analyzed with respect to the US non-proliferation policy and its expanding military presence over the Asian continent. (J.S.)
Uniform phases in fluids of hard isosceles triangles: One-component fluid and binary mixtures
Martínez-Ratón, Yuri; Díaz-De Armas, Ariel; Velasco, Enrique
2018-05-01
We formulate the scaled particle theory for a general mixture of hard isosceles triangles and calculate different phase diagrams for the one-component fluid and for certain binary mixtures. The fluid of hard triangles exhibits a complex phase behavior: (i) the presence of a triatic phase with sixfold symmetry, (ii) the isotropic-uniaxial nematic transition is of first order for certain ranges of aspect ratios, and (iii) the one-component system exhibits nematic-nematic transitions ending in critical points. We found the triatic phase to be stable not only for equilateral triangles but also for triangles of similar aspect ratios. We focus the study of binary mixtures on the case of symmetric mixtures: equal particle areas with aspect ratios (κi) symmetric with respect to the equilateral one, κ1κ2=3 . For these mixtures we found, aside from first-order isotropic-nematic and nematic-nematic transitions (the latter ending in a critical point): (i) a region of triatic phase stability even for mixtures made of particles that do not form this phase at the one-component limit, and (ii) the presence of a Landau point at which two triatic-nematic first-order transitions and a nematic-nematic demixing transition coalesce. This phase behavior is analogous to that of a symmetric three-dimensional mixture of rods and plates.
76 FR 17327 - 100th Anniversary of the Triangle Shirtwaist Factory Fire
2011-03-29
... responsibility to provide a safe environment for all American workers. NOW, THEREFORE, I, BARACK OBAMA, President... since the Triangle factory fire, we are still fighting to provide adequate working conditions for all... collective bargaining as a tool to give workers a seat at the tables of power. Working Americans are the...
The V-Flex, Triangle Orientation, and Catalan Numbers in Hexaflexagons
Iacob, Ionut E.; McLean, T. Bruce; Wang, Hua
2012-01-01
Regular hexaflexagons mysteriously change faces as you pinch flex them. This paper describes a different flex, the V-flex, which allows the hexahexaflexagon (with only 9 faces under the pinch flex) to have 3420 faces. The article goes on to explain the classification of triangle orientations in a hexaflexagon and gives an example of the…
ENVIRONMENTAL PUBLIC HEALTH OUTCOMES WORKSHOP PROCEEDINGS -RESEARCH TRIANGLE PARK, NC, 7/30-31/2002
To better define ORD's Environmental Public Health Outcomes (EPHO) research agenda, a workshop was held 7/30-31/2002 at EPA facilities in Research Triangle Park, NC. The intent of this workshop was to engage federal and other organizations in a dialog that will assist ORD in deve...
Directory of Open Access Journals (Sweden)
Ilham Rizkianto
2013-07-01
Full Text Available Previous studies have provided that when learning shapes for the first time, young children tend to use the prototype as the reference point for comparisons, but often fail when doing so since they do not yet think about the defining attributes or the geometric properties of the shapes. Most of the time, elementary students learn geometric properties of shapes only as empty verbal statements to be memorized, without any chance to experience the contepts meaningfully. In the light of it, a sequence of instructional activities along with computer manipulative was designed to support Indonesian third graders in constructing geometric properties of square, rectangle, and triangle. The aim of the present study is to develop a loval instructional theory to support third graders in constructing geometric properties of rectangle, square, and triangle. Thirty seven students of one third grade classes in SD Pupuk Sriwijaya Palembang, along with their class teacher, were involved in the study. Our findings suggest that the combination of computer and non-computer activities suppots third graders in constructing geometric properties of square, rectangle, and triangle in that it provides opportunities to the students to experience and to develop the concepts meaningfully while using their real experiences as the bases to attain a higher geometric thinking level.Key concepts: Geometric properties, rectangle, square, triangle, design research, realistic mathematics education DOI: http://dx.doi.org/10.22342/jme.4.2.414.160-171
On the chromatic number of a space with forbidden equilateral triangle
International Nuclear Information System (INIS)
Zvonarev, A E; Raigorodskii, A M; Kharlamova, A A; Samirov, D V
2014-01-01
We improve the Frankl-Rödl estimate for the product of the numbers of edges in uniform hypergraphs with forbidden cardinalities of the intersection of edges. By using this estimate, we obtain explicit bounds for the chromatic number of a space with forbidden monochromatic equilateral triangles. Bibliography: 31 titles
Decomposing series-parallel graphs into paths of length 3 and triangles
DEFF Research Database (Denmark)
Merker, Martin
2015-01-01
An old conjecture by Jünger, Reinelt and Pulleyblank states that every 2-edge-connected planar graph can be decomposed into paths of length 3 and triangles, provided its size is divisible by 3. We prove the conjecture for a class of planar graphs including all 2-edge-connected series-parallel gra...
A BPTTF-based self-assembled electron-donating triangle capable of C60 binding.
Goeb, Sébastien; Bivaud, Sébastien; Dron, Paul Ionut; Balandier, Jean-Yves; Chas, Marcos; Sallé, Marc
2012-03-25
A kinetically stable self-assembled redox-active triangle is isolated. The resulting electron-donating cavity, which incorporates three BPTTF units, exhibits a remarkable binding ability for electron-deficient C(60), supported by a favorable combination of structural and electronic features.
Kim, Joohoan
Using the viewpoint of semiotics, this paper "re-reads" Karl Marx's labor theory of value and suggests a "triple triangle" model for commodity production and shows how this model could be a model for semiosis in general. The paper argues that there are three advantages to considering homogeneity of the sign production and the…
Directory of Open Access Journals (Sweden)
Reskino
2016-08-01
Full Text Available Abstrak: Model Pendeteksian Kecurangan Laporan Keuangan dengan Analisis Fraud Triangle. Penelitian ini bertujuan untuk membuat model dalam mendeteksi kecurangan laporan keuangan. Penelitian ini menguji variabel fraud triangle dan auditor spesialis industri dengan kecurangan laporan keuangan. Sampel penelitian adalah 30 perusahaan fraud dan 30 perusahaan non-fraudyang listing di Bursa Efek Indonesia (BEI serta terkena sanksi dan kasus oleh Otoritas Jasa Keuangan (OJK. Hasil penelitian ini menunjukkan financial targetsdapat mendeteksi kecurangan laporan keuangan, sedangkan financial stabililty tidak dapat mendeteksi kecurangan laporan keuangan. Abstract: Financial Statement Fraud Detection Model with Fraud Triangle Analysis. The research purposes is to create a model to detect financial statement fraud. This research examines the variable of fraud triangle and auditor industry specialization with financial statement fraud. Samples were 30 companies of fraud and 30 non-fraud companies that were listed on the Indonesia Stock Exchange (IDX and sanctioned by the Financial Services Authority (FSA. The result shows the financial targets can be detect financial statement fraud, while financial stability can’t be detect financial statement fraud.
Combining the triangle method with thermal inertia to estimate regional evapotranspiration
DEFF Research Database (Denmark)
Stisen, Simon; Sandholt, Inge; Nørgaard, Anette
2008-01-01
Spatially distributed estimates of evaporative fraction and actual evapotranspiration are pursued using a simple remote sensing technique based on a remotely sensed vegetation index (NDVI) and diurnal changes in land surface temperature. The technique, known as the triangle method, is improved by...
Some Nice Relations between Right-Angled Triangles and the Golden Section
Scimone, Aldo
2011-01-01
The international debate about experimental approaches to the teaching and learning mathematics is very current. While number theory lends itself naturally to such approaches, elementary geometry can also provide interesting starting points for creative work in class. This article shows how simple considerations about right triangles and the…
Decompositions, partitions, and coverings with convex polygons and pseudo-triangles
Aichholzer, O.; Huemer, C.; Kappes, S.; Speckmann, B.; Tóth, Cs.D.
2007-01-01
We propose a novel subdivision of the plane that consists of both convex polygons and pseudo-triangles. This pseudo-convex decomposition is significantly sparser than either convex decompositions or pseudo-triangulations for planar point sets and simple polygons. We also introduce pseudo-convex
International Nuclear Information System (INIS)
Cao Zhi-Shen; Pan Jian; Chen Zhuo; Zhan Peng; Min Nai-Ben; Wang Zhen-Lin
2011-01-01
We experimentally and numerically investigate the optical properties of metamaterial arrays composed of double partially-overlapped metallic nanotriangles fabricated by an angle-resolved nanosphere lithography. We demonstrate that each double-triangle can be viewed as an artificial magnetic element analogous to the conventional metal split-ring-resonator. It is shown that under normal-incidence conditions, individual double-triangle can exhibit a strong local magnetic resonance, but the collective response of the metamaterial arrays is purely electric because magnetic resonances of the two double-triangles in a unit cell having opposite openings are out of phase. For oblique incidences the metamaterial arrays are shown to support a pure magnetic response at the same frequency band. Therefore, switchable electric and magnetic resonances are achieved in double-triangle arrays. Moreover, both the electric and magnetic resonances are shown to allow for a tunability over a large spectral range down to near-infrared. (condensed matter: electronic structure, electrical, magnetic, and optical properties)
Triangle Coalition for Science and Technology Education, College Park, MD.
This directory is designed to assist local action groups (existing local alliances; science mathematics, and technology teachers; superintendents, principals, and supervisors; guidance counselors and resource specialists; and university and college professors) in making contact with the local structure of the Triangle Coalition for Science and…
Pre-Metric Spaces Along with Different Types of Triangle Inequalities
Directory of Open Access Journals (Sweden)
Hsien-Chung Wu
2018-05-01
Full Text Available The T 1 -spaces induced by the pre-metric spaces along with many forms of triangle inequalities are investigated in this paper. The limits in pre-metric spaces are also studied to demonstrate the consistency of limit concept in the induced topologies.
Color Degree Sum Conditions for Rainbow Triangles in Edge-Colored Graphs
Li, Ruonan; Ning, Bo; Zhang, Shenggui
Let G be an edge-colored graph and v a vertex of G. The color degree of v is the number of colors appearing on the edges incident to v. A rainbow triangle in G is one in which all edges have distinct colors. In this paper, we first prove that an edge-colored graph on n vertices contains a rainbow
Fermat Point for a Triangle in Three Dimensions Using the Taxicab Metric
Hanson, J. R.
2017-01-01
This article explores the process of finding the Fermat point for a triangle ABC in three dimensions. Three examples are presented in detail using geometrical methods. A delightfully simple general method is then presented that requires only the comparison of coordinates of the vertices A, B and C.
Energy Technology Data Exchange (ETDEWEB)
Mourad, Daniel
2010-11-30
In this thesis, we investigate the electronic and optical properties of pure as well as of substitutionally alloyed II-VI and III-V bulk semiconductors and corresponding semiconductor quantum dots by means of an empirical tight-binding (TB) model. In the case of the alloyed systems of the type A{sub x}B{sub 1-x}, where A and B are the pure compound semiconductor materials, we study the influence of the disorder by means of several extensions of the TB model with different levels of sophistication. Our methods range from rather simple mean-field approaches (virtual crystal approximation, VCA) over a dynamical mean-field approach (coherent potential approximation, CPA) up to calculations where substitutional disorder is incorporated on a finite ensemble of microscopically distinct configurations. In the first part of this thesis, we cover the necessary fundamentals in order to properly introduce the TB model of our choice, the effective bond-orbital model (EBOM). In this model, one s- and three p-orbitals per spin direction are localized on the sites of the underlying Bravais lattice. The matrix elements between these orbitals are treated as free parameters in order to reproduce the properties of one conduction and three valence bands per spin direction and can then be used in supercell calculations in order to model mixed bulk materials or pure as well as mixed quantum dots. Part II of this thesis deals with unalloyed systems. Here, we use the EBOM in combination with configuration interaction calculations for the investigation of the electronic and optical properties of truncated pyramidal GaN quantum dots embedded in AlN with an underlying zincblende structure. Furthermore, we develop a parametrization of the EBOM for materials with a wurtzite structure, which allows for a fit of one conduction and three valence bands per spin direction throughout the whole Brillouin zone of the hexagonal system. In Part III, we focus on the influence of alloying on the electronic
Irreversible stochastic processes on lattices
International Nuclear Information System (INIS)
Nord, R.S.
1986-01-01
Models for irreversible random or cooperative filling of lattices are required to describe many processes in chemistry and physics. Since the filling is assumed to be irreversible, even the stationary, saturation state is not in equilibrium. The kinetics and statistics of these processes are described by recasting the master equations in infinite hierarchical form. Solutions can be obtained by implementing various techniques: refinements in these solution techniques are presented. Programs considered include random dimer, trimer, and tetramer filling of 2D lattices, random dimer filling of a cubic lattice, competitive filling of two or more species, and the effect of a random distribution of inactive sites on the filling. Also considered is monomer filling of a linear lattice with nearest neighbor cooperative effects and solve for the exact cluster-size distribution for cluster sizes up to the asymptotic regime. Additionally, a technique is developed to directly determine the asymptotic properties of the cluster size distribution. Finally cluster growth is considered via irreversible aggregation involving random walkers. In particular, explicit results are provided for the large-lattice-size asymptotic behavior of trapping probabilities and average walk lengths for a single walker on a lattice with multiple traps. Procedures for exact calculation of these quantities on finite lattices are also developed
Toward lattice fractional vector calculus
International Nuclear Information System (INIS)
Tarasov, Vasily E
2014-01-01
An analog of fractional vector calculus for physical lattice models is suggested. We use an approach based on the models of three-dimensional lattices with long-range inter-particle interactions. The lattice analogs of fractional partial derivatives are represented by kernels of lattice long-range interactions, where the Fourier series transformations of these kernels have a power-law form with respect to wave vector components. In the continuum limit, these lattice partial derivatives give derivatives of non-integer order with respect to coordinates. In the three-dimensional description of the non-local continuum, the fractional differential operators have the form of fractional partial derivatives of the Riesz type. As examples of the applications of the suggested lattice fractional vector calculus, we give lattice models with long-range interactions for the fractional Maxwell equations of non-local continuous media and for the fractional generalization of the Mindlin and Aifantis continuum models of gradient elasticity. (papers)
Human zonulin, a potential modulator of intestinal tight junctions.
Wang, W; Uzzau, S; Goldblum, S E; Fasano, A
2000-12-01
Intercellular tight junctions are dynamic structures involved in vectorial transport of water and electrolytes across the intestinal epithelium. Zonula occludens toxin derived from Vibrio cholerae interacts with a specific intestinal epithelial surface receptor, with subsequent activation of a complex intracellular cascade of events that regulate tight junction permeability. We postulated that this toxin may mimic the effect of a functionally and immunologically related endogenous modulator of intestinal tight junctions. Affinity-purified anti-zonula occludens toxin antibodies and the Ussing chamber assay were used to screen for one or more mammalian zonula occludens toxin analogues in both fetal and adult human intestine. A novel protein, zonulin, was identified that induces tight junction disassembly in non-human primate intestinal epithelia mounted in Ussing chambers. Comparison of amino acids in the active zonula occludens toxin fragment and zonulin permitted the identification of the putative receptor binding domain within the N-terminal region of the two proteins. Zonulin likely plays a pivotal role in tight junction regulation during developmental, physiological, and pathological processes, including tissue morphogenesis, movement of fluid, macromolecules and leukocytes between the intestinal lumen and the interstitium, and inflammatory/autoimmune disorders.
The media of sociology: tight or loose translations?
Guggenheim, Michael
2015-06-01
Sociologists have increasingly come to recognize that the discipline has unduly privileged textual representations, but efforts to incorporate visual and other media are still only in their beginning. This paper develops an analysis of the ways objects of knowledge are translated into other media, in order to understand the visual practices of sociology and to point out unused possibilities. I argue that the discourse on visual sociology, by assuming that photographs are less objective than text, is based on an asymmetric media-determinism and on a misleading notion of objectivity. Instead, I suggest to analyse media with the concept of translations. I introduce several kinds of translations, most centrally the distinction between tight and loose ones. I show that many sciences, such as biology, focus on tight translations, using a variety of media and manipulating both research objects and representations. Sociology, in contrast, uses both tight and loose translations, but uses the latter only for texts. For visuals, sociology restricts itself to what I call 'the documentary': focusing on mechanical recording technologies without manipulating either the object of research or the representation. I conclude by discussing three rare examples of what is largely excluded in sociology: visual loose translations, visual tight translations based on non-mechanical recording technologies, and visual tight translations based on mechanical recording technologies that include the manipulation of both object and representation. © London School of Economics and Political Science 2015.
Introduction to lattice gauge theory
International Nuclear Information System (INIS)
Gupta, R.
1987-01-01
The lattice formulation of Quantum Field Theory (QFT) can be exploited in many ways. We can derive the lattice Feynman rules and carry out weak coupling perturbation expansions. The lattice then serves as a manifestly gauge invariant regularization scheme, albeit one that is more complicated than standard continuum schemes. Strong coupling expansions: these give us useful qualitative information, but unfortunately no hard numbers. The lattice theory is amenable to numerical simulations by which one calculates the long distance properties of a strongly interacting theory from first principles. The observables are measured as a function of the bare coupling g and a gauge invariant cut-off ≅ 1/α, where α is the lattice spacing. The continuum (physical) behavior is recovered in the limit α → 0, at which point the lattice artifacts go to zero. This is the more powerful use of lattice formulation, so in these lectures the author focuses on setting up the theory for the purpose of numerical simulations to get hard numbers. The numerical techniques used in Lattice Gauge Theories have their roots in statistical mechanics, so it is important to develop an intuition for the interconnection between quantum mechanics and statistical mechanics. This will be the emphasis of the first lecture. In the second lecture, the author reviews the essential ingredients of formulating QCD on the lattice and discusses scaling and the continuum limit. In the last lecture the author summarizes the status of some of the main results. He also mentions the bottlenecks and possible directions for research. 88 refs
The Mass-Longevity Triangle: Pareto Optimality and the Geometry of Life-History Trait Space
Szekely, Pablo; Korem, Yael; Moran, Uri; Mayo, Avi; Alon, Uri
2015-01-01
When organisms need to perform multiple tasks they face a fundamental tradeoff: no phenotype can be optimal at all tasks. This situation was recently analyzed using Pareto optimality, showing that tradeoffs between tasks lead to phenotypes distributed on low dimensional polygons in trait space. The vertices of these polygons are archetypes—phenotypes optimal at a single task. This theory was applied to examples from animal morphology and gene expression. Here we ask whether Pareto optimality theory can apply to life history traits, which include longevity, fecundity and mass. To comprehensively explore the geometry of life history trait space, we analyze a dataset of life history traits of 2105 endothermic species. We find that, to a first approximation, life history traits fall on a triangle in log-mass log-longevity space. The vertices of the triangle suggest three archetypal strategies, exemplified by bats, shrews and whales, with specialists near the vertices and generalists in the middle of the triangle. To a second approximation, the data lies in a tetrahedron, whose extra vertex above the mass-longevity triangle suggests a fourth strategy related to carnivory. Each animal species can thus be placed in a coordinate system according to its distance from the archetypes, which may be useful for genome-scale comparative studies of mammalian aging and other biological aspects. We further demonstrate that Pareto optimality can explain a range of previous studies which found animal and plant phenotypes which lie in triangles in trait space. This study demonstrates the applicability of multi-objective optimization principles to understand life history traits and to infer archetypal strategies that suggest why some mammalian species live much longer than others of similar mass. PMID:26465336
The Mass-Longevity Triangle: Pareto Optimality and the Geometry of Life-History Trait Space.
Szekely, Pablo; Korem, Yael; Moran, Uri; Mayo, Avi; Alon, Uri
2015-10-01
When organisms need to perform multiple tasks they face a fundamental tradeoff: no phenotype can be optimal at all tasks. This situation was recently analyzed using Pareto optimality, showing that tradeoffs between tasks lead to phenotypes distributed on low dimensional polygons in trait space. The vertices of these polygons are archetypes--phenotypes optimal at a single task. This theory was applied to examples from animal morphology and gene expression. Here we ask whether Pareto optimality theory can apply to life history traits, which include longevity, fecundity and mass. To comprehensively explore the geometry of life history trait space, we analyze a dataset of life history traits of 2105 endothermic species. We find that, to a first approximation, life history traits fall on a triangle in log-mass log-longevity space. The vertices of the triangle suggest three archetypal strategies, exemplified by bats, shrews and whales, with specialists near the vertices and generalists in the middle of the triangle. To a second approximation, the data lies in a tetrahedron, whose extra vertex above the mass-longevity triangle suggests a fourth strategy related to carnivory. Each animal species can thus be placed in a coordinate system according to its distance from the archetypes, which may be useful for genome-scale comparative studies of mammalian aging and other biological aspects. We further demonstrate that Pareto optimality can explain a range of previous studies which found animal and plant phenotypes which lie in triangles in trait space. This study demonstrates the applicability of multi-objective optimization principles to understand life history traits and to infer archetypal strategies that suggest why some mammalian species live much longer than others of similar mass.
The Mass-Longevity Triangle: Pareto Optimality and the Geometry of Life-History Trait Space.
Directory of Open Access Journals (Sweden)
Pablo Szekely
2015-10-01
Full Text Available When organisms need to perform multiple tasks they face a fundamental tradeoff: no phenotype can be optimal at all tasks. This situation was recently analyzed using Pareto optimality, showing that tradeoffs between tasks lead to phenotypes distributed on low dimensional polygons in trait space. The vertices of these polygons are archetypes--phenotypes optimal at a single task. This theory was applied to examples from animal morphology and gene expression. Here we ask whether Pareto optimality theory can apply to life history traits, which include longevity, fecundity and mass. To comprehensively explore the geometry of life history trait space, we analyze a dataset of life history traits of 2105 endothermic species. We find that, to a first approximation, life history traits fall on a triangle in log-mass log-longevity space. The vertices of the triangle suggest three archetypal strategies, exemplified by bats, shrews and whales, with specialists near the vertices and generalists in the middle of the triangle. To a second approximation, the data lies in a tetrahedron, whose extra vertex above the mass-longevity triangle suggests a fourth strategy related to carnivory. Each animal species can thus be placed in a coordinate system according to its distance from the archetypes, which may be useful for genome-scale comparative studies of mammalian aging and other biological aspects. We further demonstrate that Pareto optimality can explain a range of previous studies which found animal and plant phenotypes which lie in triangles in trait space. This study demonstrates the applicability of multi-objective optimization principles to understand life history traits and to infer archetypal strategies that suggest why some mammalian species live much longer than others of similar mass.
Lattice Methods for Quantum Chromodynamics
DeGrand, Thomas
2006-01-01
Numerical simulation of lattice-regulated QCD has become an important source of information about strong interactions. In the last few years there has been an explosion of techniques for performing ever more accurate studies on the properties of strongly interacting particles. Lattice predictions directly impact many areas of particle and nuclear physics theory and phenomenology. This book provides a thorough introduction to the specialized techniques needed to carry out numerical simulations of QCD: a description of lattice discretizations of fermions and gauge fields, methods for actually do
Localized structures in Kagome lattices
Energy Technology Data Exchange (ETDEWEB)
Saxena, Avadh B [Los Alamos National Laboratory; Bishop, Alan R [Los Alamos National Laboratory; Law, K J H [UNIV OF MASSACHUSETTS; Kevrekidis, P G [UNIV OF MASSACHUSETTS
2009-01-01
We investigate the existence and stability of gap vortices and multi-pole gap solitons in a Kagome lattice with a defocusing nonlinearity both in a discrete case and in a continuum one with periodic external modulation. In particular, predictions are made based on expansion around a simple and analytically tractable anti-continuum (zero coupling) limit. These predictions are then confirmed for a continuum model of an optically-induced Kagome lattice in a photorefractive crystal obtained by a continuous transformation of a honeycomb lattice.
Lattice QCD: Status and Prospect
International Nuclear Information System (INIS)
Ukawa, Akira
2006-01-01
A brief review is given of the current status and near-future prospect of lattice QCD studies of the Standard Model. After summarizing a bit of history, we describe current attempts toward inclusion of dynamical up, down and strange quarks. Recent results on the light hadron mass spectrum as well as those on the heavy quark quantities are described. Recent work on lattice pentaquark search is summarized. We touch upon the PACS-CS Project for building our next machine for lattice QCD, and conclude with a summary of computer situation and the physics possibilities over the next several years
Borwein, J M; McPhedran, R C
2013-01-01
The study of lattice sums began when early investigators wanted to go from mechanical properties of crystals to the properties of the atoms and ions from which they were built (the literature of Madelung's constant). A parallel literature was built around the optical properties of regular lattices of atoms (initiated by Lord Rayleigh, Lorentz and Lorenz). For over a century many famous scientists and mathematicians have delved into the properties of lattices, sometimes unwittingly duplicating the work of their predecessors. Here, at last, is a comprehensive overview of the substantial body of
Lattice disorder in strongly correlated lanthanide and actinide intermetallics
International Nuclear Information System (INIS)
Booth, C.H.; Bauer, E.D.; Maple, M.B.; Lawrence, J.M.; Kwei, G.H.; Sarrao, J.L.
2001-01-01
Lanthanide and actinide intermetallic compounds display a wide range of correlated-electron behavior, including ferromagnetism, antiferromagnetism, nonmagnetic (Kondo) ground states, and so-called 'non-Fermi liquid' (NFL) behavior. The interaction between f electrons and the conduction band is a dominant factor in determining the ground state of a given system. However, lattice disorder can create a distribution of interactions, generating unusual physical properties. These properties may include NFL behavior in many materials. In addition, lattice disorder can cause deviations from standard Kondo behavior that is less severe than NFL behavior. A review of the lattice disorder mechanism within a tight-binding model is presented, along with measurements of the YbBCu 4 and UPd x Cu 5-x systems, demonstrating the applicability of the model. These measurements indicate that while the YbBCu 4 system appears to be well ordered, both site interchange and continuous bond-length disorder occur in the UPd x Cu 5-x series. Nevertheless, the measured bond-length disorder in UPdCu 4 does not appear to be enough to explain the NFL properties simply with the Kondo disorder model. (au)
From lattice Hamiltonians to tunable band structures by lithographic design
Tadjine, Athmane; Allan, Guy; Delerue, Christophe
2016-08-01
Recently, new materials exhibiting exotic band structures characterized by Dirac cones, nontrivial flat bands, and band crossing points have been proposed on the basis of effective two-dimensional lattice Hamiltonians. Here, we show using atomistic tight-binding calculations that these theoretical predictions could be experimentally realized in the conduction band of superlattices nanolithographed in III-V and II-VI semiconductor ultrathin films. The lithographed patterns consist of periodic lattices of etched cylindrical holes that form potential barriers for the electrons in the quantum well. In the case of honeycomb lattices, the conduction minibands of the resulting artificial graphene host several Dirac cones and nontrivial flat bands. Similar features, but organized in different ways, in energy or in k -space are found in kagome, distorted honeycomb, and Lieb superlattices. Dirac cones extending over tens of meV could be obtained in superlattices with reasonable sizes of the lithographic patterns, for instance in InAs/AlSb heterostructures. Bilayer artificial graphene could be also realized by lithography of a double quantum-well heterostructure. These new materials should be interesting for the experimental exploration of Dirac-based quantum systems, for both fundamental and applied physics.
Quantum degenerate atomic gases in controlled optical lattice potentials
Gemelke, Nathan D.
2007-12-01
Since the achievement of Bose Einstein condensation in cold atomic gases, mean-field treatments of the condensed phase have provided an excellent description for the static and dynamic properties observed in experiments. Recent experimental efforts have focused on studying deviations from mean-field behavior. I will describe work on two experiments which introduce controlled single particle degeneracies with time-dependent optical potentials, aiming to induce correlated motion and nontrivial statistics in the gas. In the first experiment, an optical lattice with locally rotating site potentials is produced to investigate fractional quantum Hall effects (FQHE) in rotating Bose gases. Here, the necessary gauge potential is provided by the rotating reference frame of the gas, which, in direct analogy to the electronic system, organizes single particle states into degenerate Landau levels. At low temperatures the repulsive interaction provided by elastic scattering is expected to produce ground states with structure nearly identical to those in the FQHE. I will discuss how these effects are made experimentally feasible by working at small particle numbers in the tight trapping potentials of an optical lattice, and present first results on the use of photoassociation to probe correlation in this system. In the second experiment, a vibrated optical lattice potential alters the single-particle dispersion underlying a condensed Bose gas and offers tailored phase-matching for nonlinear atom optical processes. I will demonstrate how this leads to parametric instability in the condensed gas, and draw analogy to an optical parametric oscillator operating above threshold.
Tallarita, Gianni; Peterson, Adam
2018-04-01
We perform a numerical study of the phase diagram of the model proposed in [M. Shifman, Phys. Rev. D 87, 025025 (2013)., 10.1103/PhysRevD.87.025025], which is a simple model containing non-Abelian vortices. As per the case of Abrikosov vortices, we map out a region of parameter space in which the system prefers the formation of vortices in ordered lattice structures. These are generalizations of Abrikosov vortex lattices with extra orientational moduli in the vortex cores. At sufficiently large lattice spacing the low energy theory is described by a sum of C P (1 ) theories, each located on a vortex site. As the lattice spacing becomes smaller, when the self-interaction of the orientational field becomes relevant, only an overall rotation in internal space survives.
Zhu, Wenbin; Jia, Shaofeng; Lv, Aifeng
2017-10-01
The triangle method based on the spatial relationship between remotely sensed land surface temperature (Ts) and vegetation index (VI) has been widely used for the estimates of evaporative fraction (EF). In the present study, a universal triangle method was proposed by transforming the Ts-VI feature space from a regional scale to a pixel scale. The retrieval of EF is only related to the boundary conditions at pixel scale, regardless of the Ts-VI configuration over the spatial domain. The boundary conditions of each pixel are composed of the theoretical dry edge determined by the surface energy balance principle and the wet edge determined by the average air temperature of open water. The universal triangle method was validated using the EF observations collected by the Energy Balance Bowen Ratio systems in the Southern Great Plains of the United States of America (USA). Two parameterization schemes of EF were used to demonstrate their applicability with Terra Moderate Resolution Imaging Spectroradiometer (MODIS) products over the whole year 2004. The results of this study show that the accuracy produced by both of these two parameterization schemes is comparable to that produced by the traditional triangle method, although the universal triangle method seems specifically suited to the parameterization scheme proposed in our previous research. The independence of the universal triangle method from the Ts-VI feature space makes it possible to conduct a continuous monitoring of evapotranspiration and soil moisture. That is just the ability the traditional triangle method does not possess.
Lattice Studies of Hyperon Spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Richards, David G. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2016-04-01
I describe recent progress at studying the spectrum of hadrons containing the strange quark through lattice QCD calculations. I emphasise in particular the richness of the spectrum revealed by lattice studies, with a spectrum of states at least as rich as that of the quark model. I conclude by prospects for future calculations, including in particular the determination of the decay amplitudes for the excited states.
Harmonic oscillator on a lattice
International Nuclear Information System (INIS)
Ader, J.P.; Bonnier, B.; Hontebeyrie, M.; Meyers, C.
1983-01-01
The continuum limit of the ground state energy for the harmonic oscillator with discrete time is derived for all possible choices of the lattice derivative. The occurrence of unphysical values is shown to arise whenever the lattice laplacian is not strictly positive on its Brillouin zone. These undesirable limits can either be finite and arbitrary (multiple spectrum) or infinite (overlapping sublattices with multiple spectrum). (orig.)
International Nuclear Information System (INIS)
DeGrand, T.
1997-01-01
These lectures provide an introduction to lattice methods for nonperturbative studies of Quantum Chromodynamics. Lecture 1: Basic techniques for QCD and results for hadron spectroscopy using the simplest discretizations; lecture 2: Improved actions--what they are and how well they work; lecture 3: SLAC physics from the lattice-structure functions, the mass of the glueball, heavy quarks and α s (M z ), and B-anti B mixing. 67 refs., 36 figs
Takami, A.; Hashimoto, T.; Horibe, M.; Hayashi, A.
2000-01-01
The Wigner functions on the one dimensional lattice are studied. Contrary to the previous claim in literature, Wigner functions exist on the lattice with any number of sites, whether it is even or odd. There are infinitely many solutions satisfying the conditions which reasonable Wigner functions should respect. After presenting a heuristic method to obtain Wigner functions, we give the general form of the solutions. Quantum mechanical expectation values in terms of Wigner functions are also ...
Energy Technology Data Exchange (ETDEWEB)
DeGrand, T. [Univ. of Colorado, Boulder, CO (United States). Dept. of Physics
1997-06-01
These lectures provide an introduction to lattice methods for nonperturbative studies of Quantum Chromodynamics. Lecture 1: Basic techniques for QCD and results for hadron spectroscopy using the simplest discretizations; lecture 2: Improved actions--what they are and how well they work; lecture 3: SLAC physics from the lattice-structure functions, the mass of the glueball, heavy quarks and {alpha}{sub s} (M{sub z}), and B-{anti B} mixing. 67 refs., 36 figs.
Racetrack lattices for the TRIUMF KAON factory
International Nuclear Information System (INIS)
Servranckx, R.V.; Wienands, U.; Craddock, M.K.; Rees, G.H.
1989-03-01
Separated-function racetrack lattices have been developed for the KAON Factory accelerators that have more flexibility than the old circular lattices. Straight sections with zero dispersion are provided for rf cavities and fast injection and extraction, and with controlled dispersion for H - injection and slow extraction. In addition the new lattices have fewer depolarizing resonances than the old circular lattices
Lattice gauge theory using parallel processors
International Nuclear Information System (INIS)
Lee, T.D.; Chou, K.C.; Zichichi, A.
1987-01-01
The book's contents include: Lattice Gauge Theory Lectures: Introduction and Current Fermion Simulations; Monte Carlo Algorithms for Lattice Gauge Theory; Specialized Computers for Lattice Gauge Theory; Lattice Gauge Theory at Finite Temperature: A Monte Carlo Study; Computational Method - An Elementary Introduction to the Langevin Equation, Present Status of Numerical Quantum Chromodynamics; Random Lattice Field Theory; The GF11 Processor and Compiler; and The APE Computer and First Physics Results; Columbia Supercomputer Project: Parallel Supercomputer for Lattice QCD; Statistical and Systematic Errors in Numerical Simulations; Monte Carlo Simulation for LGT and Programming Techniques on the Columbia Supercomputer; Food for Thought: Five Lectures on Lattice Gauge Theory
Tight Temporal Bounds for Dataflow Applications Mapped onto Shared Resources
Alizadeh Ara, H.; Geilen, M.; Basten, T.; Behrouzian, A.R.B.; Hendriks, M.; Goswami, D.
2016-01-01
We present an analysis method that provides tight temporal bounds for applications modeled by Synchronous Dataflow Graphs and mapped to shared resources. We consider the resource sharing effects on the temporal behaviour of the application by embedding worst case resource availability curves in the
Ultra-Tightly Coupled GNSS/INS for small UAVs
DEFF Research Database (Denmark)
Olesen, Daniel; Jakobsen, Jakob; Knudsen, Per
2017-01-01
This paper describes an ultra-tight integration of a Global Navigation Satellite System ( GNSS) receiver and an Inertial Navigation System ( INS) for small Unmanned Aerial Vehicles ( UAVs). The system is based on a low-cost and low-weight GNSS Intermediate Frequency ( IF) sampler which has been...
Management of Small Urethrocutaneous Fistula by Tight Ligation ...
African Journals Online (AJOL)
After identifying the fistulous opening, the fistula tract was circumferentially and meticulously dissected ,then the dissected tract was lifted up and the base was ligated tightly with 5/0 vicryl, the external epithelium of the dissected tract was fulgurated with the diathermy, then a second layer of local soft tissue was secured over ...
A characterization of tight and dual generalized translation invariant frames
DEFF Research Database (Denmark)
Jakobsen, Mads Sielemann; Lemvig, Jakob
2015-01-01
such systems form tight frames, and when two GTI Bessel systems form dual frames for L2(G). In particular, this offers a unified approach to the theory of discrete and continuous frames and, e.g., yields well known results for discrete and continuous Gabor and wavelet systems....
Envelopes of Sets of Measures, Tightness, and Markov Control Processes
International Nuclear Information System (INIS)
Gonzalez-Hernandez, J.; Hernandez-Lerma, O.
1999-01-01
We introduce upper and lower envelopes for sets of measures on an arbitrary topological space, which are then used to give a tightness criterion. These concepts are applied to show the existence of optimal policies for a class of Markov control processes
Trapping of Rydberg atoms in tight magnetic microtraps
Boetes, A.Q.G.; Skannrup, R.V.; Naber, J.; Kokkelmans, S.J.J.M.F.; Spreeuw, R.J.C.
2018-01-01
We explore the possibility to trap Rydberg atoms in tightly confining magnetic microtraps. The trapping frequencies for Rydberg atoms are expected to be influenced strongly by magnetic-field gradients. We show that there are regimes where Rydberg atoms can be trapped. Moreover, we show that
Dielectric constant of graphene-on-polarized substrate: A tight ...
Indian Academy of Sciences (India)
Sivabrata Sahu
Corresponding author. E-mail: gcr@iopb.res.in. Published online 24 June 2017. Abstract. We report here a microscopic tight-binding theoretical study of the dynamic dielectric response of graphene-on-polarizable substrate with impurity. The Hamiltonian consists of first, second and third nearest- neighbour electron hopping ...
Dielectric constant of graphene-on-polarized substrate: A tight ...
Indian Academy of Sciences (India)
2017-06-24
Jun 24, 2017 ... We report here a microscopic tight-binding theoretical study of the dynamic dielectric response of graphene-on-polarizable substrate with impurity. The Hamiltonian consists of first, second and third nearest neighbour electron hopping interactions besides doping and substrate-induced effects on graphene.
Loosen up? Cultural tightness and national entrepreneurial activity
Harms, Rainer; Groen, Arend J.
The level of entrepreneurship between countries differs consistently. A source of this variance lies in national culture differences. Recently, the cultural dimension “tightness” has been introduced in the literature. Tightness refers to the degree to which a nation has strong norms and a low
Prediction of Gas Leak Tightness of Superplastically Formed Products
Snippe, Q.H.C.; Meinders, Vincent T.; Barlat, F; Moon, Y.H.; Lee, M.G.
2010-01-01
In some applications, in this case an aluminium box in a subatomic particle detector containing highly sensitive detecting devices, it is important that a formed sheet should show no gas leak from one side to the other. In order to prevent a trial-and-error procedure to make this leak tight box, a
Sit-Tight Syndrome and Tenure Elongation in African Politics ...
African Journals Online (AJOL)
The post-independence politics of African countries has been dominated by the phenomenon of sit-tight African heads of state and government who had acceeded to office by election or coup d'etat. This paper examines this recurring problem in post-independence African politics by examining its general and specific ...
Unconventional Tight Reservoirs Characterization with Nuclear Magnetic Resonance
Santiago, C. J. S.; Solatpour, R.; Kantzas, A.
2017-12-01
The increase in tight reservoir exploitation projects causes producing many papers each year on new, modern, and modified methods and techniques on estimating characteristics of these reservoirs. The most ambiguous of all basic reservoir property estimations deals with permeability. One of the logging methods that is advertised to predict permeability but is always met by skepticism is Nuclear Magnetic Resonance (NMR). The ability of NMR to differentiate between bound and movable fluids and providing porosity increased the capability of NMR as a permeability prediction technique. This leads to a multitude of publications and the motivation of a review paper on this subject by Babadagli et al. (2002). The first part of this presentation is dedicated to an extensive review of the existing correlation models for NMR based estimates of tight reservoir permeability to update this topic. On the second part, the collected literature information is used to analyze new experimental data. The data are collected from tight reservoirs from Canada, the Middle East, and China. A case study is created to apply NMR measurement in the prediction of reservoir characterization parameters such as porosity, permeability, cut-offs, irreducible saturations etc. Moreover, permeability correlations are utilized to predict permeability. NMR experiments were conducted on water saturated cores. NMR T2 relaxation times were measured. NMR porosity, the geometric mean relaxation time (T2gm), Irreducible Bulk Volume (BVI), and Movable Bulk Volume (BVM) were calculated. The correlation coefficients were computed based on multiple regression analysis. Results are cross plots of NMR permeability versus the independently measured Klinkenberg corrected permeability. More complicated equations are discussed. Error analysis of models is presented and compared. This presentation is beneficial in understanding existing tight reservoir permeability models. The results can be used as a guide for choosing
Embedded Lattice and Properties of Gram Matrix
Directory of Open Access Journals (Sweden)
Futa Yuichi
2017-03-01
Full Text Available In this article, we formalize in Mizar [14] the definition of embedding of lattice and its properties. We formally define an inner product on an embedded module. We also formalize properties of Gram matrix. We formally prove that an inverse of Gram matrix for a rational lattice exists. Lattice of Z-module is necessary for lattice problems, LLL (Lenstra, Lenstra and Lov´asz base reduction algorithm [16] and cryptographic systems with lattice [17].
The Design of 3D-Printed Lattice-Reinforced Thickness-Varying Shell Molds for Castings.
Shangguan, Haolong; Kang, Jinwu; Yi, Jihao; Zhang, Xiaochuan; Wang, Xiang; Wang, Haibin; Huang, Tao
2018-03-30
3D printing technologies have been used gradually for the fabrication of sand molds and cores for castings, even though these molds and cores are dense structures. In this paper, a generation method for lattice-reinforced thickness-varying shell molds is proposed and presented. The first step is the discretization of the STL (Stereo Lithography) model of a casting into finite difference meshes. After this, a shell is formed by surrounding the casting with varying thickness, which is roughly proportional to the surface temperature distribution of the casting that is acquired by virtually cooling it in the environment. A regular lattice is subsequently constructed to support the shell. The outside surface of the shell and lattice in the cubic mesh format is then converted to STL format to serve as the external surface of the new shell mold. The internal surface of the new mold is the casting's surface with the normals of all of the triangles in STL format reversed. Experimental verification was performed on an Al alloy wheel hub casting. Its lattice-reinforced thickness-varying shell mold was generated by the proposed method and fabricated by the binder jetting 3D printing. The poured wheel hub casting was sound and of good surface smoothness. The cooling rate of the wheel hub casting was greatly increased due to the shell mold structure. This lattice-reinforced thickness-varying shell mold generation method is of great significance for mold design for castings to achieve cooling control.
The Design of 3D-Printed Lattice-Reinforced Thickness-Varying Shell Molds for Castings
Shangguan, Haolong; Kang, Jinwu; Yi, Jihao; Zhang, Xiaochuan; Wang, Xiang; Wang, Haibin; Huang, Tao
2018-01-01
3D printing technologies have been used gradually for the fabrication of sand molds and cores for castings, even though these molds and cores are dense structures. In this paper, a generation method for lattice-reinforced thickness-varying shell molds is proposed and presented. The first step is the discretization of the STL (Stereo Lithography) model of a casting into finite difference meshes. After this, a shell is formed by surrounding the casting with varying thickness, which is roughly proportional to the surface temperature distribution of the casting that is acquired by virtually cooling it in the environment. A regular lattice is subsequently constructed to support the shell. The outside surface of the shell and lattice in the cubic mesh format is then converted to STL format to serve as the external surface of the new shell mold. The internal surface of the new mold is the casting’s surface with the normals of all of the triangles in STL format reversed. Experimental verification was performed on an Al alloy wheel hub casting. Its lattice-reinforced thickness-varying shell mold was generated by the proposed method and fabricated by the binder jetting 3D printing. The poured wheel hub casting was sound and of good surface smoothness. The cooling rate of the wheel hub casting was greatly increased due to the shell mold structure. This lattice-reinforced thickness-varying shell mold generation method is of great significance for mold design for castings to achieve cooling control. PMID:29601543
The Design of 3D-Printed Lattice-Reinforced Thickness-Varying Shell Molds for Castings
Directory of Open Access Journals (Sweden)
Haolong Shangguan
2018-03-01
Full Text Available 3D printing technologies have been used gradually for the fabrication of sand molds and cores for castings, even though these molds and cores are dense structures. In this paper, a generation method for lattice-reinforced thickness-varying shell molds is proposed and presented. The first step is the discretization of the STL (Stereo Lithography model of a casting into finite difference meshes. After this, a shell is formed by surrounding the casting with varying thickness, which is roughly proportional to the surface temperature distribution of the casting that is acquired by virtually cooling it in the environment. A regular lattice is subsequently constructed to support the shell. The outside surface of the shell and lattice in the cubic mesh format is then converted to STL format to serve as the external surface of the new shell mold. The internal surface of the new mold is the casting’s surface with the normals of all of the triangles in STL format reversed. Experimental verification was performed on an Al alloy wheel hub casting. Its lattice-reinforced thickness-varying shell mold was generated by the proposed method and fabricated by the binder jetting 3D printing. The poured wheel hub casting was sound and of good surface smoothness. The cooling rate of the wheel hub casting was greatly increased due to the shell mold structure. This lattice-reinforced thickness-varying shell mold generation method is of great significance for mold design for castings to achieve cooling control.
Sheldon, Kennon M; Schachtman, Todd R
2007-04-01
Schlenker's triangle model (Schlenker, Britt, Pennington, Murphy, & Doherty, 1994, Schlenker, Pontari, & Christopher, 2001) identifies three excuses people use to avoid taking responsibility after failure: that one had no control in the situation, that the obligation was unclear, and that it was not really one's obligation. Three retrospective studies tested the presumed negative association between excuse making and responsibility taking. The studies also examined the effects of self-determination theory's concept of motivational internalization (Deci & Ryan, 2000) upon these variables. A complex but replicable pattern emerged, such that responsibility taking and motivational internalization correlated with adaptive outcomes such as future commitment and positive expectancy and excuse making did not. Of particular interest, perceiving that the person levying the obligation internalized motivation predicted responsibility taking, in all three studies. Implications for the triangle model, as well as for theories of maturity and personality development, are considered.
Khuluqi, M. H.; Prapdito, R. R.; Sambodo, F. P.
2018-04-01
In Indonesia, mining is categorized as a hazardous industry. In recent years, a dramatic increase of mining equipment and technological complexities had resulted in higher maintenance expectations that accompanied by the changes in the working conditions, especially on safety. Ensuring safety during the process of conducting maintenance works in underground mine is important as an integral part of accident prevention programs. Accident triangle has provided a support to safety practitioner to draw a road map in preventing accidents. Poisson distribution is appropriate for the analysis of accidents at a specific site in a given time period. Based on the analysis of accident statistics in the underground mine maintenance of PT. Freeport Indonesia from 2011 through 2016, it is found that 12 minor accidents for 1 major accident and 66 equipment damages for 1 major accident as a new value of accident triangle. The result can be used for the future need for improving the accident prevention programs.
The use of triangle diagram in the detection of explosive and illicit drugs
Sudac, Davorin; Baricevic, Martina; Obhodas, Jasmina; Franulovic, Andrej; Valkovic, Vladivoj
2010-04-01
A tagged neutron inspection system has been used for the detection of explosive and illicite drugs. Simulant of the RDX explosive was measured in different environments and its gamma ray spectra were compared with the gamma ray spectra of benign materials like paper, sugar and rise. "Fingerprint" of the RDX simulant was found by detecting the nitrogen as well as by making the triangle plot which coordinates show the carbon and oxygen content and density. Density was obtained by measuring the intensity of the transmited tagged neutrons. Hence, the presence of the simulant can be confirmed by using two different methods. The possibility of using the triangle plot for detection of illicit drugs like heroin, cocain and marihuana is also discused.
Surface charge method for molecular surfaces with curved areal elements I. Spherical triangles
Yu, Yi-Kuo
2018-03-01
Parametrizing a curved surface with flat triangles in electrostatics problems creates a diverging electric field. One way to avoid this is to have curved areal elements. However, charge density integration over curved patches appears difficult. This paper, dealing with spherical triangles, is the first in a series aiming to solve this problem. Here, we lay the ground work for employing curved patches for applying the surface charge method to electrostatics. We show analytically how one may control the accuracy by expanding in powers of the the arc length (multiplied by the curvature). To accommodate not extremely small curved areal elements, we have provided enough details to include higher order corrections that are needed for better accuracy when slightly larger surface elements are used.
Analysing Diagnostic Assessment on the Ratio of Sine in a Right Triangle
Andika, R.; Juandi, D.; Rosjanuardi, R.
2017-09-01
This study aims to develop diagnostic assessment with the special topic of the ratio of sinus in a right triangle and analyze the result whether the students are ready to continue to the next lesson of trigonometry specially the sinus rule. The methodology that use in this study is a design research of Plomp model which is it comprises of 3 phases: (a) preliminary research; (b) prototyping phase; and (c) assessment phase. The findings show that almost half of students made a mistake in determining the ratio of sin in a right triangle, consequently the procedure for solving the problem went wrong. In strategic competency and adaptive communication most of students did not solve the problem that was given. According to the result, the students have to get remedial program before to the next lesson, the rule of sin.
Remarks on the P{sub c} structures and triangle singularities
Energy Technology Data Exchange (ETDEWEB)
Guo, Feng-Kun [Chinese Academy of Science, CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Beijing (China); Meissner, Ulf G. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Bonn (Germany); Forschungszentrum Juelich, Institute for Advanced Simulation, Institut fuer Kernphysik and Juelich Center for Hadron Physics, Juelich (Germany); Nieves, Juan [Centro Mixto CSIC-Universidad de Valencia, Institutos de Investigacion de Paterna, Instituto de Fisica Corpuscular (IFIC), Valencia (Spain); Yang, Zhi [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Bonn (Germany)
2016-10-15
It was proposed that the narrow P{sub c}(4450) structure observed by the LHCb Collaboration in the reaction Λ{sub b} → J/ψpK might be due to a triangle singularity around the χ{sub c1}-proton threshold at 4.45 GeV. We discuss the occurrence of a similar triangle singularity in the J/ψp invariant mass distribution for the decay Λ{sub b} → J/ψpπ, which could explain the bump around 4.45 GeV in the data. More precise measurements of this process would provide valuable information towards an understanding of the P{sub c} structures. (orig.)
Pascal (Yang Hui) triangles and power laws in the logistic map
International Nuclear Information System (INIS)
Velarde, Carlos; Robledo, Alberto
2015-01-01
We point out the joint occurrence of Pascal triangle patterns and power-law scaling in the standard logistic map, or more generally, in unimodal maps. It is known that these features are present in its two types of bifurcation cascades: period and chaotic-band doubling of attractors. Approximate Pascal triangles are exhibited by the sets of lengths of supercycle diameters and by the sets of widths of opening bands. Additionally, power-law scaling manifests along periodic attractor supercycle positions and chaotic band splitting points. Consequently, the attractor at the mutual accumulation point of the doubling cascades, the onset of chaos, displays both Gaussian and power-law distributions. Their combined existence implies both ordinary and exceptional statistical-mechanical descriptions of dynamical properties. (paper)
An Interactive Control Algorithm Used for Equilateral Triangle Formation with Robotic Sensors
Li, Xiang; Chen, Hongcai
2014-01-01
This paper describes an interactive control algorithm, called Triangle Formation Algorithm (TFA), used for three neighboring robotic sensors which are distributed randomly to self-organize into and equilateral triangle (E) formation. The algorithm is proposed based on the triangular geometry and considering the actual sensors used in robotics. In particular, the stability of the TFA, which can be executed by robotic sensors independently and asynchronously for E formation, is analyzed in details based on Lyapunov stability theory. Computer simulations are carried out for verifying the effectiveness of the TFA. The analytical results and simulation studies indicate that three neighboring robots employing conventional sensors can self-organize into E formations successfully regardless of their initial distribution using the same TFAs. PMID:24759118
Weak matrix elements on the lattice - Circa 1995
International Nuclear Information System (INIS)
Soni, A.
1995-01-01
Status of weak matrix elements is reviewed. In particular, e'/e, B → K*γ, B B and B B , are discussed and the overall situation with respect to the lattice effort and some of its phenomenological implications are summarised. For e'/e the need for the relevant matrix elements is stressed in view of the forthcoming improved experiments. For some of the operators, (e.g. O 6 ), even bound on their matrix elements would be very helpful. On B → K degrees γ, a constant behavior of T 2 appears disfavored although dependence of T 2 could, of course, be milder than a simple pole. Improved data is badly needed to settle this important issue firmly, especially in view of its ramification for extractions of V td from B → ργ. On B κ , the preliminary result from JLQCD appears to contradict Sharpe et al. JLQCD data seems to fit very well to linear α dependence and leads to an appreciably lower value of B κ . Four studies of B κ in the open-quotes fullclose quotes (n f = 2) theory indicate very little quenching effects on B κ ; the full theory value seems to be just a little less than the quenched result. Based on expectations from HQET, analysis of B-parameter (B h ell) for the heavy-light mesons via B h ell) = constant + constants'/m h ell is suggested. A summary of an illustrative sample of hadron matrix elements is given and constraints on CKM parameters (e.g. V td /V ts , on the unitarity triangle and on x s /x d , emerging from the lattice calculations along with experimental results are briefly discussed. In quite a few cases, for the first time, some indication of quenching errors on weak matrix elements are now becoming available
Spinning and tumbling of micron-sized triangles in a micro-channel shear flow
Fries, J.; Kumar, M. Vijay; Mihiretie, B. Mekonnen; Hanstorp, D.; Mehlig, B.
2018-03-01
We report on measurements of the angular dynamics of micron-sized equilaterally triangular platelets suspended in a micro-channel shear flow. Our measurements confirm that such particles spin and tumble like a spheroid in a simple shear. Since the triangle has corners, we can observe the spinning directly. In general, the spinning frequency is different from the tumbling frequency and the spinning is affected by tumbling. This gives rise to doubly periodic angular dynamics.
International Nuclear Information System (INIS)
Seagondollar, L.W.; Waltner, A.W.; Mitchell, G.E.; Tilley, D.R.; Gould, C.R.
1975-01-01
A summary is presented of nuclear structure research completed at the Triangle Universities Nuclear Lab for the period 9/1/74 to 8/31/75. Included are abstracts and titles for studies of electromagnetic transitions in low-medium mass nuclei, high resolution studies, accelerator induced x-ray investigations, and energy related neutron and charged particle cross section measurements. (U.S.)
Directory of Open Access Journals (Sweden)
Sobhy Serry Dessouky
2016-08-01
The evaluation is carried out on DGA data obtained from three different groups of transformers. A Matlab program was developed to automate the evaluation of Duval Triangle graph to numerical modification, Also the fault gases can be generated due to oil decomposing effected by transformer over excitation which increasing thetransformer exciting current lead to rising the temperature inside transformer core beside the other causes.
Triangles, tricks and tics: Hyper-mentalizing in response to animated shapes in Tourette syndrome.
Eddy, Clare M; Cavanna, Andrea E
2015-10-01
Tourette syndrome (TS) can feature complex tics involving socially inappropriate behaviours. Adults with TS can also demonstrate differences to healthy controls when reasoning about mental states. This study investigated spontaneous mentalizing in TS. Twenty adults with TS and twenty healthy controls completed the animations task. Participants were asked to watch short ambiguous animations involving two triangles and describe what was happening. Some animations featured random movement of the triangles, while others depicted social interactions that were simple (e.g., dancing) or more complex (e.g., one triangle tricking the other). Measures were taken of executive functions, alexithymia and clinical symptoms. Individuals with TS responded similarly to controls when viewing animations featuring simple and complex interactions, demonstrating intact mentalizing ability. However, significant group differences were apparent for the random movement animations. TS was associated with a greater tendency to attribute mental states during this condition, and to describe random movements as motivated actions guided by the intentions of the triangles. There were no group differences for the alexithymia scale, but TS was associated with mild executive deficits. No relationships were apparent between animation responses and other measures. Our findings suggest that TS is associated with a propensity to adopt the intentional stance. Hyper-mentalizing in TS could be linked to both dopamine dysfunction and altered social behaviour, whereby amplified salience of social cues could contribute to the complex interplay between environmental context and tic expression. These observations may offer further insight into the potential effects of dopamine dysfunction on social cognition. Copyright © 2015 Elsevier Ltd. All rights reserved.
Concept of Triangle: Examples of Mathematical Abstraction in Two Different Contexts
Directory of Open Access Journals (Sweden)
Farida Nurhasanah
2017-02-01
Full Text Available In attempt to explain how students learning geometry in concept of triangle, this study explore the learning process of students and the process of solving geometry problems in the topic of triangle. As known as one of the domain in school of mathematics, geometry has abstract notions to be learnt so that all those notions cannot be just transferred into students’ mind like a bunch of information that should be memorized. Students need to construct those concepts during their learning process. This process of knowledge construction can be considered as an abstraction process. This study aimed to qualitatively compare students’ abstraction process who learn topic of triangle in conventional method of teaching and in van Hiele model of teaching aided by Geometers’ sketchpad. Subjects of this study were junir high school students in grade 7. Based on the aims of this study, this is a qualitative study with grounded theory design. Data were collected through classroom observation, test, and task-based interview. Results of the study show that theoretical abstraction processes tend to dominate classrom with conventional method of teaching while classroom with van Hiele model of teaching aided by Geometers’ sketchpad accommodated empirical abstraction process of the students
Cressey’s fraud triangle (1953 and agency theory: study applied to brazilian banking institutions
Directory of Open Access Journals (Sweden)
Michele Rílany Rodrigues Machado
2017-08-01
Full Text Available This research examined if Cressey’s (1953 fraud triangle and the agency theory, jointly, enables investigate corporate fraud occurrence in Brazilian banking institutions. It was formulated six research hypotheses were segregated in fraud triangle – pressure, opportunity and rationalization – and measured by variables taken from the agency theory, criminology and empirical papers on corporate fraud. The identification of probability of fraud occurrence was operationalized from multinomial logistic model, applied to data of 44 banking, for the period between January 2001 and December 2012. For element pressure, hypotheses No. 01 was confirmed, since this showed that the lower an institution’s previous performance, the greater probability there is of fraudulent events occurring in the future. In the element of opportunity, the hypothesis No. 03 was confirmed, which showed that low corporate governance indicators increased the possibility of fraud occurrences. In rationalization element, the hypothesis No. 08 was confirmed, therefore, the predominance of women in management reduces the probability of fraud. We thereby conclude that Cressey’s Triangle, when combined with the theory of agency is an appropriate research instrument to use when carrying out an investigation into corporate fraud occurrence in banking institutions.
Pose Self-Measurement of Noncooperative Spacecraft Based on Solar Panel Triangle Structure
Directory of Open Access Journals (Sweden)
Jingzhou Song
2015-01-01
Full Text Available Aiming at the recognition and location of noncooperative spacecraft, this paper presents a monocular vision pose measurement method based on solar triangle structure. First of all, an autonomous recognition algorithm of feature structure based on sliding window Hough transformation (SWHT and inscribed circle of a triangle is proposed, and the image coordinates of feature points on the triangle can be obtained relying on this algorithm, combined with the P4P algorithm and the structure of spacecraft, calculating the relative pose of target expressed by rotation and translation matrix. The whole algorithm can be loaded into the prewritten onboard program, which will get the autocomplete feature structure extraction and relative pose measurement without human intervention, and this method does not need to mount any markers on the target. Then compare the measured values with the accurate value of the laser tracker, so that a conclusion can be drawn that the maximum position error is lower than 5% and the rotation error is lower than 4%, which meets the requirements of noncooperative spacecraft’s pose measurement for observations, tracking, and docking in the final rendezvous phase.
Assessing the plasmonics of gold nano-triangles with higher order laser modes
Directory of Open Access Journals (Sweden)
Laura E. Hennemann
2012-10-01
Full Text Available Regular arrays of metallic nano-triangles – so called Fischer patterns – are fabricated by nano-sphere lithography. We studied such gold nano-triangle arrays on silicon or glass substrates. A series of different samples was investigated with a parabolic mirror based confocal microscope where the sample is scanned through the laser focus. By employing higher order laser modes (azimuthally and radially polarised laser beams, we can excite the Fischer patterns using either a pure in-plane (x,y electric field or a strongly z-directional (optical axis of the optical microscope electric field. We collected and evaluated the emitted luminescence and thereby investigated the respectively excited plasmonic modes. These varied considerably: firstly with the light polarisation in the focus, secondly with the aspect ratio of the triangles and thirdly with the employed substrate. Moreover, we obtained strongly enhanced Raman spectra of an adenine (sub-monolayer on gold Fischer patterns on glass. We thus showed that gold Fischer patterns are promising surface-enhanced Raman scattering (SERS substrates.
Available pressure amplitude of linear compressor based on phasor triangle model
Duan, C. X.; Jiang, X.; Zhi, X. Q.; You, X. K.; Qiu, L. M.
2017-12-01
The linear compressor for cryocoolers possess the advantages of long-life operation, high efficiency, low vibration and compact structure. It is significant to study the match mechanisms between the compressor and the cold finger, which determines the working efficiency of the cryocooler. However, the output characteristics of linear compressor are complicated since it is affected by many interacting parameters. The existing matching methods are simplified and mainly focus on the compressor efficiency and output acoustic power, while neglecting the important output parameter of pressure amplitude. In this study, a phasor triangle model basing on analyzing the forces of the piston is proposed. It can be used to predict not only the output acoustic power, the efficiency, but also the pressure amplitude of the linear compressor. Calculated results agree well with the measurement results of the experiment. By this phasor triangle model, the theoretical maximum output pressure amplitude of the linear compressor can be calculated simply based on a known charging pressure and operating frequency. Compared with the mechanical and electrical model of the linear compressor, the new model can provide an intuitionistic understanding on the match mechanism with faster computational process. The model can also explain the experimental phenomenon of the proportional relationship between the output pressure amplitude and the piston displacement in experiments. By further model analysis, such phenomenon is confirmed as an expression of the unmatched design of the compressor. The phasor triangle model may provide an alternative method for the compressor design and matching with the cold finger.
International Nuclear Information System (INIS)
Doncheski, M.A.; Robinett, R.W.
2002-01-01
Using the fact that the energy eigenstates of the equilateral triangle infinite well (or billiard) are available in closed form, we examine the connections between the energy eigenvalue spectrum and the classical closed paths in this geometry, using both periodic orbit theory and the short-term semi-classical behavior of wave packets. We also discuss wave packet revivals and show that there are exact revivals, for all wave packets, at times given by T rev =9μa 2 /4(h/2π) where a and μ are the length of one side and the mass of the point particle, respectively. We find additional cases of exact revivals with shorter revival times for zero-momentum wave packets initially located at special symmetry points inside the billiard. Finally, we discuss simple variations on the equilateral (60 deg. -60 deg. -60 deg. ) triangle, such as the half equilateral (30 deg. -60 deg. -90 deg.) triangle and other 'foldings', which have related energy spectra and revival structures
Macmillan, N A; Creelman, C D
1996-06-01
Can accuracy and response bias in two-stimulus, two-response recognition or detection experiments be measured nonparametrically? Pollack and Norman (1964) answered this question affirmatively for sensitivity, Hodos (1970) for bias: Both proposed measures based on triangular areas in receiver-operating characteristic space. Their papers, and especially a paper by Grier (1971) that provided computing formulas for the measures, continue to be heavily cited in a wide range of content areas. In our sample of articles, most authors described triangle-based measures as making fewer assumptions than measures associated with detection theory. However, we show that statistics based on products or ratios of right triangle areas, including a recently proposed bias index and a not-yetproposed but apparently plausible sensitivity index, are consistent with a decision process based on logistic distributions. Even the Pollack and Norman measure, which is based on non-right triangles, is approximately logistic for low values of sensitivity. Simple geometric models for sensitivity and bias are not nonparametric, even if their implications are not acknowledged in the defining publications.
Advanced Hydraulic Fracturing Technology for Unconventional Tight Gas Reservoirs
Energy Technology Data Exchange (ETDEWEB)
Stephen Holditch; A. Daniel Hill; D. Zhu
2007-06-19
The objectives of this project are to develop and test new techniques for creating extensive, conductive hydraulic fractures in unconventional tight gas reservoirs by statistically assessing the productivity achieved in hundreds of field treatments with a variety of current fracturing practices ranging from 'water fracs' to conventional gel fracture treatments; by laboratory measurements of the conductivity created with high rate proppant fracturing using an entirely new conductivity test - the 'dynamic fracture conductivity test'; and by developing design models to implement the optimal fracture treatments determined from the field assessment and the laboratory measurements. One of the tasks of this project is to create an 'advisor' or expert system for completion, production and stimulation of tight gas reservoirs. A central part of this study is an extensive survey of the productivity of hundreds of tight gas wells that have been hydraulically fractured. We have been doing an extensive literature search of the SPE eLibrary, DOE, Gas Technology Institute (GTI), Bureau of Economic Geology and IHS Energy, for publicly available technical reports about procedures of drilling, completion and production of the tight gas wells. We have downloaded numerous papers and read and summarized the information to build a database that will contain field treatment data, organized by geographic location, and hydraulic fracture treatment design data, organized by the treatment type. We have conducted experimental study on 'dynamic fracture conductivity' created when proppant slurries are pumped into hydraulic fractures in tight gas sands. Unlike conventional fracture conductivity tests in which proppant is loaded into the fracture artificially; we pump proppant/frac fluid slurries into a fracture cell, dynamically placing the proppant just as it occurs in the field. From such tests, we expect to gain new insights into some of the critical
Finite-lattice-spacing corrections to masses and g factors on a lattice
International Nuclear Information System (INIS)
Roskies, R.; Wu, J.C.
1986-01-01
We suggest an alternative method for extracting masses and g factors from lattice calculations. Our method takes account of more of the infrared and ultraviolet lattice effects. It leads to more reasonable results in simulations of QED on a lattice
Quantum lattice model solver HΦ
Kawamura, Mitsuaki; Yoshimi, Kazuyoshi; Misawa, Takahiro; Yamaji, Youhei; Todo, Synge; Kawashima, Naoki
2017-08-01
HΦ [aitch-phi ] is a program package based on the Lanczos-type eigenvalue solution applicable to a broad range of quantum lattice models, i.e., arbitrary quantum lattice models with two-body interactions, including the Heisenberg model, the Kitaev model, the Hubbard model and the Kondo-lattice model. While it works well on PCs and PC-clusters, HΦ also runs efficiently on massively parallel computers, which considerably extends the tractable range of the system size. In addition, unlike most existing packages, HΦ supports finite-temperature calculations through the method of thermal pure quantum (TPQ) states. In this paper, we explain theoretical background and user-interface of HΦ. We also show the benchmark results of HΦ on supercomputers such as the K computer at RIKEN Advanced Institute for Computational Science (AICS) and SGI ICE XA (Sekirei) at the Institute for the Solid State Physics (ISSP).
Lattice QCD for nuclear physics
Meyer, Harvey
2015-01-01
With ever increasing computational resources and improvements in algorithms, new opportunities are emerging for lattice gauge theory to address key questions in strongly interacting systems, such as nuclear matter. Calculations today use dynamical gauge-field ensembles with degenerate light up/down quarks and the strange quark and it is possible now to consider including charm-quark degrees of freedom in the QCD vacuum. Pion masses and other sources of systematic error, such as finite-volume and discretization effects, are beginning to be quantified systematically. Altogether, an era of precision calculation has begun, and many new observables will be calculated at the new computational facilities. The aim of this set of lectures is to provide graduate students with a grounding in the application of lattice gauge theory methods to strongly interacting systems, and in particular to nuclear physics. A wide variety of topics are covered, including continuum field theory, lattice discretizations, hadron spect...
Nucleon structure from lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Dinter, Simon
2012-11-13
In this thesis we compute within lattice QCD observables related to the structure of the nucleon. One part of this thesis is concerned with moments of parton distribution functions (PDFs). Those moments are essential elements for the understanding of nucleon structure and can be extracted from a global analysis of deep inelastic scattering experiments. On the theoretical side they can be computed non-perturbatively by means of lattice QCD. However, since the time lattice calculations of moments of PDFs are available, there is a tension between these lattice calculations and the results from a global analysis of experimental data. We examine whether systematic effects are responsible for this tension, and study particularly intensively the effects of excited states by a dedicated high precision computation. Moreover, we carry out a first computation with four dynamical flavors. Another aspect of this thesis is a feasibility study of a lattice QCD computation of the scalar quark content of the nucleon, which is an important element in the cross-section of a heavy particle with the nucleon mediated by a scalar particle (e.g. Higgs particle) and can therefore have an impact on Dark Matter searches. Existing lattice QCD calculations of this quantity usually have a large error and thus a low significance for phenomenological applications. We use a variance-reduction technique for quark-disconnected diagrams to obtain a precise result. Furthermore, we introduce a new stochastic method for the calculation of connected 3-point correlation functions, which are needed to compute nucleon structure observables, as an alternative to the usual sequential propagator method. In an explorative study we check whether this new method is competitive to the standard one. We use Wilson twisted mass fermions at maximal twist in all our calculations, such that all observables considered here have only O(a{sup 2}) discretization effects.
Nucleon structure from lattice QCD
International Nuclear Information System (INIS)
Dinter, Simon
2012-01-01
In this thesis we compute within lattice QCD observables related to the structure of the nucleon. One part of this thesis is concerned with moments of parton distribution functions (PDFs). Those moments are essential elements for the understanding of nucleon structure and can be extracted from a global analysis of deep inelastic scattering experiments. On the theoretical side they can be computed non-perturbatively by means of lattice QCD. However, since the time lattice calculations of moments of PDFs are available, there is a tension between these lattice calculations and the results from a global analysis of experimental data. We examine whether systematic effects are responsible for this tension, and study particularly intensively the effects of excited states by a dedicated high precision computation. Moreover, we carry out a first computation with four dynamical flavors. Another aspect of this thesis is a feasibility study of a lattice QCD computation of the scalar quark content of the nucleon, which is an important element in the cross-section of a heavy particle with the nucleon mediated by a scalar particle (e.g. Higgs particle) and can therefore have an impact on Dark Matter searches. Existing lattice QCD calculations of this quantity usually have a large error and thus a low significance for phenomenological applications. We use a variance-reduction technique for quark-disconnected diagrams to obtain a precise result. Furthermore, we introduce a new stochastic method for the calculation of connected 3-point correlation functions, which are needed to compute nucleon structure observables, as an alternative to the usual sequential propagator method. In an explorative study we check whether this new method is competitive to the standard one. We use Wilson twisted mass fermions at maximal twist in all our calculations, such that all observables considered here have only O(a 2 ) discretization effects.
Directory of Open Access Journals (Sweden)
Pradeep K. Luther
2014-12-01
Full Text Available Myosin filaments in vertebrate striated muscle have a long roughly cylindrical backbone with cross-bridge projections on the surfaces of both halves except for a short central bare zone. In the middle of this central region the filaments are cross-linked by the M-band which holds them in a well-defined hexagonal lattice in the muscle A-band. During muscular contraction the M-band-defined rotation of the myosin filaments around their long axes influences the interactions that the cross-bridges can make with the neighbouring actin filaments. We can visualise this filament rotation by electron microscopy of thin cross-sections in the bare-region immediately adjacent to the M-band where the filament profiles are distinctly triangular. In the muscles of teleost fishes, the thick filament triangular profiles have a single orientation giving what we call the simple lattice. In other vertebrates, for example all the tetrapods, the thick filaments have one of two orientations where the triangles point in opposite directions (they are rotated by 60° or 180° according to set rules. Such a distribution cannot be developed in an ordered fashion across a large 2D lattice, but there are small domains of superlattice such that the next-nearest neighbouring thick filaments often have the same orientation. We believe that this difference in the lattice forms can lead to different contractile behaviours. Here we provide a historical review, and when appropriate cite recent work related to the emergence of the simple and superlattice forms by examining the muscles of several species ranging back to primitive vertebrates and we discuss the functional differences that the two lattice forms may have.
Kondo length in bosonic lattices
Giuliano, Domenico; Sodano, Pasquale; Trombettoni, Andrea
2017-09-01
Motivated by the fact that the low-energy properties of the Kondo model can be effectively simulated in spin chains, we study the realization of the effect with bond impurities in ultracold bosonic lattices at half filling. After presenting a discussion of the effective theory and of the mapping of the bosonic chain onto a lattice spin Hamiltonian, we provide estimates for the Kondo length as a function of the parameters of the bosonic model. We point out that the Kondo length can be extracted from the integrated real-space correlation functions, which are experimentally accessible quantities in experiments with cold atoms.
Supersymmetry on the noncommutative lattice
International Nuclear Information System (INIS)
Nishimura, Jun; Rey, Soo-Jong; Sugino, Fumihiko
2003-01-01
Built upon the proposal of Kaplan et al. (heplat{0206109}), we construct noncommutative lattice gauge theory with manifest supersymmetry. We show that such theory is naturally implementable via orbifold conditions generalizing those used by Kaplan et al. We present the prescription in detail and illustrate it for noncommutative gauge theories latticized partially in two dimensions. We point out a deformation freedom in the defining theory by a complex-parameter, reminiscent of discrete torsion in string theory. We show that, in the continuum limit, the supersymmetry is enhanced only at a particular value of the deformation parameter, determined solely by the size of the noncommutativity. (author)
Machines for lattice gauge theory
International Nuclear Information System (INIS)
Mackenzie, P.B.
1989-05-01
The most promising approach to the solution of the theory of strong interactions is large scale numerical simulation using the techniques of lattice gauge theory. At the present time, computing requirements for convincing calculations of the properties of hadrons exceed the capabilities of even the most powerful commercial supercomputers. This has led to the development of massively parallel computers dedicated to lattice gauge theory. This talk will discuss the computing requirements behind these machines, and general features of the components and architectures of the half dozen major projects now in existence. 20 refs., 1 fig
Graphene on graphene antidot lattices
DEFF Research Database (Denmark)
Gregersen, Søren Schou; Pedersen, Jesper Goor; Power, Stephen
2015-01-01
Graphene bilayer systems are known to exhibit a band gap when the layer symmetry is broken by applying a perpendicular electric field. The resulting band structure resembles that of a conventional semiconductor with a parabolic dispersion. Here, we introduce a bilayer graphene heterostructure......, where single-layer graphene is placed on top of another layer of graphene with a regular lattice of antidots. We dub this class of graphene systems GOAL: graphene on graphene antidot lattice. By varying the structure geometry, band-structure engineering can be performed to obtain linearly dispersing...
Unconventional superconductivity in honeycomb lattice
Directory of Open Access Journals (Sweden)
P Sahebsara
2013-03-01
Full Text Available The possibility of symmetrical s-wave superconductivity in the honeycomb lattice is studied within a strongly correlated regime, using the Hubbard model. The superconducting order parameter is defined by introducing the Green function, which is obtained by calculating the density of the electrons . In this study showed that the superconducting order parameter appears in doping interval between 0 and 0.5, and x=0.25 is the optimum doping for the s-wave superconductivity in honeycomb lattice.
[Lattice degeneration of the retina].
Boĭko, E V; Suetov, A A; Mal'tsev, D S
2014-01-01
Lattice degeneration of the retina is a clinically important type of peripheral retinal dystrophies due to its participation in the pathogenesis of rhegmatogenous retinal detachment. In spite of extensive epidemiological, morphological, and clinical data, the question on causes of this particular type of retinal dystrophies currently remains debatable. Existing hypotheses on pathogenesis of retinal structural changes in lattice degeneration explain it to a certain extent. In clinical ophthalmology it is necessary to pay close attention to this kind of degenerations and distinguish between cases requiring preventive treatment and those requiring monitoring.
Lattice calculations in gauge theory
International Nuclear Information System (INIS)
Rebbi, C.
1985-01-01
The lattice formulation of quantum gauge theories is discussed as a viable technique for quantitative studies of nonperturbative effects in QCD. Evidence is presented to ascertain that whole classes of lattice actions produce a universal continuum limit. Discrepancies between numerical results from Monto Carlo simulations for the pure gauge system and for the system with gauge and quark fields are discussed. Numerical calculations for QCD require very substantial computational resources. The use of powerful vector processors of special purpose machines, in extending the scope and magnitude or the calculations is considered, and one may reasonably expect that in the near future good quantitative predictions will be obtained for QCD
Chiral symmetry on the lattice
International Nuclear Information System (INIS)
Creutz, M.
1994-11-01
The author reviews some of the difficulties associated with chiral symmetry in the context of a lattice regulator. The author discusses the structure of Wilson Fermions when the hopping parameter is in the vicinity of its critical value. Here one flavor contrasts sharply with the case of more, where a residual chiral symmetry survives anomalies. The author briefly discusses the surface mode approach, the use of mirror Fermions to cancel anomalies, and finally speculates on the problems with lattice versions of the standard model
Nuclear Physics from Lattice QCD
Energy Technology Data Exchange (ETDEWEB)
William Detmold, Silas Beane, Konstantinos Orginos, Martin Savage
2011-01-01
We review recent progress toward establishing lattice Quantum Chromodynamics as a predictive calculational framework for nuclear physics. A survey of the current techniques that are used to extract low-energy hadronic scattering amplitudes and interactions is followed by a review of recent two-body and few-body calculations by the NPLQCD collaboration and others. An outline of the nuclear physics that is expected to be accomplished with Lattice QCD in the next decade, along with estimates of the required computational resources, is presented.
Preconditioning Filter Bank Decomposition Using Structured Normalized Tight Frames
Directory of Open Access Journals (Sweden)
Martin Ehler
2015-01-01
Full Text Available We turn a given filter bank into a filtering scheme that provides perfect reconstruction, synthesis is the adjoint of the analysis part (so-called unitary filter banks, all filters have equal norm, and the essential features of the original filter bank are preserved. Unitary filter banks providing perfect reconstruction are induced by tight generalized frames, which enable signal decomposition using a set of linear operators. If, in addition, frame elements have equal norm, then the signal energy is spread through the various filter bank channels in some uniform fashion, which is often more suitable for further signal processing. We start with a given generalized frame whose elements allow for fast matrix vector multiplication, as, for instance, convolution operators, and compute a normalized tight frame, for which signal analysis and synthesis still preserve those fast algorithmic schemes.
Some Effective Tight-Binding Models for Electrons in DNA Conduction: A Review
International Nuclear Information System (INIS)
Yamada, H.; Iguchi, K.
2010-01-01
Quantum transport for DNA conduction has been widely studied with interest in application as a candidate in making nanowires as well as interest in the scientific mechanism. In this paper, we review recent works concerning the electronic states and the conduction/transfer in DNA polymers. We have mainly investigated the energy-band structure and the correlation effects of localization property in the two- and three-chain systems (ladder model) with long-range correlation as a simple model for electronic property in a double strand of DNA by using the tight-bindingmodel. In addition, we investigated the localization properties of electronic states in several actual DNA sequences such as bacteriophages of Escherichia coli, human-chromosome 22, compared with those of the artificial disordered sequences with correlation. The charge-transfer properties for poly(dA)-poly(dT) and poly(dG)-poly(dC) DNA polymers are also presented in terms of localization lengths within the frameworks of the polaron models due to the coupling between the charge carriers and the lattice vibrations of the double strand of DNA
Li, L. L.; Partoens, B.; Peeters, F. M.
2018-04-01
By taking account of the electric-field-induced charge screening, a self-consistent calculation within the framework of the tight-binding approach is employed to obtain the electronic band structure of gated multilayer phosphorene and the charge densities on the different phosphorene layers. We find charge density and screening anomalies in single-gated multilayer phosphorene and electron-hole bilayers in dual-gated multilayer phosphorene. Due to the unique puckered lattice structure, both intralayer and interlayer charge screenings are important in gated multilayer phosphorene. We find that the electric-field tuning of the band structure of multilayer phosphorene is distinctively different in the presence and absence of charge screening. For instance, it is shown that the unscreened band gap of multilayer phosphorene decreases dramatically with increasing electric-field strength. However, in the presence of charge screening, the magnitude of this band-gap decrease is significantly reduced and the reduction depends strongly on the number of phosphorene layers. Our theoretical results of the band-gap tuning are compared with recent experiments and good agreement is found.
The search for a source rock for the giant Tar Sand triangle accumulation, southeastern Utah
Huntoon, J.E.; Hansley, P.L.; Naeser, N.D.
1999-01-01
A large proportion (about 36%) of the world's oil resource is contained in accumulations of heavy oil or tar. In these large deposits of degraded oil, the oil in place represents only a fraction of what was present at the time of accumulation. In many of these deposits, the source of the oil is unknown, and the oil is thought to have migrated over long distances to the reservoirs. The Tar Sand triangle in southeastern Utah contains the largest tar sand accumulation in the United States, with 6.3 billion bbl of heavy oil estimated to be in place. The deposit is thought to have originally contained 13-16 billion bbl prior to the biodegradation, water washing, and erosion that have taken place since the middle - late Tertiary. The source of the oil is unknown. The tar is primarily contained within the Lower Permian White Rim Sandstone, but extends into permeable parts of overlying and underlying beds. Oil is interpreted to have migrated into the White Rim sometime during the Tertiary when the formation was at a depth of approximately 3500 m. This conclusion is based on integration of fluid inclusion analysis, time-temperature reconstruction, and apatite fission-track modeling for the White Rim Sandstone. Homogenization temperatures cluster around 85-90??C for primary fluid inclusions in authigenic, nonferroan dolomite in the White Rim. The fluid inclusions are associated with fluorescent oil-bearing inclusions, indicating that dolomite precipitation was coeval with oil migration. Burial reconstruction suggests that the White Rim Sandstone reached its maximum burial depth from 60 to 24 Ma, and that maximum burial was followed by unroofing from 24 to 0 Ma. Time-temperature modeling indicates that the formation experienced temperatures of 85-90??C from about 35 to 40 Ma during maximum burial. Maximum formation temperatures of about 105-110??C were reached at about 24 Ma, just prior to unroofing. Thermal modeling is used to examine the history of potential source rocks
Tight Network Topology Dependent Bounds on Rounds of Communication
Chattopadhyay, Arkadev; Langberg, Michael; Li, Shi; Rudra, Atri
2016-01-01
We prove tight network topology dependent bounds on the round complexity of computing well studied $k$-party functions such as set disjointness and element distinctness. Unlike the usual case in the CONGEST model in distributed computing, we fix the function and then vary the underlying network topology. This complements the recent such results on total communication that have received some attention. We also present some applications to distributed graph computation problems. Our main contri...
Integral tightness measurements at the Paks-1 nuclear reactor
Energy Technology Data Exchange (ETDEWEB)
Taubner, R.; Techy, Z. (Villamosenergiaipari Kutato Intezet, Budapest (Hungary))
1983-01-01
The containment system experiments of the Paks-1 nuclear reactor are described. The integrated tightness measurements of the hermetic system were completed in 1982. The principles and methods and the evaluation of the results of the measurements are discussed. Some features of the filtration characteristics are demonstrated using relative values and a method enabling the description of the physical contents of the characteristics by flow technical functions is outlined.
Quantum tight-binding chains with dissipative coupling
International Nuclear Information System (INIS)
Mogilevtsev, D; Slepyan, G Ya; Garusov, E; Kilin, S Ya; Korolkova, N
2015-01-01
We present a one-dimensional tight-binding chain of two-level systems coupled only through common dissipative Markovian reservoirs. This quantum chain can demonstrate anomalous thermodynamic behavior contradicting Fourier law. Population dynamics of individual systems of the chain is polynomial with the order determined by the initial state of the chain. The chain can simulate classically hard problems, such as multi-dimensional random walks. (paper)
Thermography Control of Heat Insulation and Tightness of Buildings,
1980-11-01
construction. The method is pedagogical . Results from thermography studies are suitable for use when giving experience feedback. (Excellent complement...visual inspection Instrument Various tools and measures. Principle The construction is opened, and the workmanship of insulation and tight- ness is...most IR cameras. At -196 C (77K) it is sensitive within the wavelength range 0 - 5.6 jam. The lower - 24 - FIGURE 3: Photography with IR camera, AGA
Tightly localized stationary pulses in a multilevel atomic system
International Nuclear Information System (INIS)
Liu, Xiong-Jun; Oh, C. H.; Liu, Xin; Liu, Zheng-Xin; Kwek, L. C.
2007-01-01
We show that the pulse matching phenomenon can be obtained in the general multilevel system with electromagnetically induced transparency. For this we find a different way to create tightly localized stationary pulses by using counterpropagating pump fields. The present process is a spatial compression of excitation so that it allows us to shape and further intensify the localized stationary pulses, without using standing waves of pump fields or spatially modulated pump fields
International Nuclear Information System (INIS)
Eustermann, Fabian; Stegemann, Frank; Renner, Konstantin; Janka, Oliver
2017-01-01
The compounds of the REPt 6 Al 3 series (RE = Ce-Nd, Sm, Gd, Tb) were obtained by reaction of the elements via arc-melting. They were characterized by powder and single-crystal X-ray diffraction (NdPt 6 Al 3 : wR = 0.0432, 759 F 2 values, 33 variables) as well as by magnetic susceptibility measurements. The isostructural compounds crystallize with a new structure type in the trigonal crystal system with space group R anti 3c, twelve formula units in the unit cell, and lattice parameters of a = 752-755 and c = 3882-3945 pm. The crystal structure can be described by different slabs stacked along [001]. One layer features Pt 3 triangles, centering the cavities of a flat honeycomb RE layer that are arranged in a..ABCA ' B ' C ' .. sequence. The other layer consists of condensed hexagonal [Pt 6 Al 6 ] prisms, centered by Pt atoms, separating the before mentioned slabs. Magnetic measurements revealed that all rare-earth atoms are in the trivalent oxidation state, however, due to the low lanthanoide content magnetic ordering phenomena were observed only at low temperatures [SmPt 6 Al 3 : T C = 5.0(1) K; GdPt 6 Al 3 : T C = 7.3(1) K; TbPt 6 Al 3 : T N = 3.6(1) K]. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Representation theory of lattice current algebras
International Nuclear Information System (INIS)
Alekseev, A.Yu.; Eidgenoessische Technische Hochschule, Zurich; Faddeev, L.D.; Froehlich, L.D.; Schomerus, V.; Kyoto Univ.
1996-04-01
Lattice current algebras were introduced as a regularization of the left-and right moving degrees of freedom in the WZNW model. They provide examples of lattice theories with a local quantum symmetry U q (G). Their representation theory is studied in detail. In particular, we construct all irreducible representations along with a lattice analogue of the fusion product for representations of the lattice current algebra. It is shown that for an arbitrary number of lattice sites, the representation categories of the lattice current algebras agree with their continuum counterparts. (orig.)
Tight junction regulates epidermal calcium ion gradient and differentiation
International Nuclear Information System (INIS)
Kurasawa, Masumi; Maeda, Tetsuo; Oba, Ai; Yamamoto, Takuya; Sasaki, Hiroyuki
2011-01-01
Research highlights: → We disrupted epidermal tight junction barrier in reconstructed epidermis. → It altered Ca 2+ distribution and consequentially differentiation state as well. → Tight junction should affect epidermal homeostasis by maintaining Ca 2+ gradient. -- Abstract: It is well known that calcium ions (Ca 2+ ) induce keratinocyte differentiation. Ca 2+ distributes to form a vertical gradient that peaks at the stratum granulosum. It is thought that the stratum corneum (SC) forms the Ca 2+ gradient since it is considered the only permeability barrier in the skin. However, the epidermal tight junction (TJ) in the granulosum has recently been suggested to restrict molecular movement to assist the SC as a secondary barrier. The objective of this study was to clarify the contribution of the TJ to Ca 2+ gradient and epidermal differentiation in reconstructed human epidermis. When the epidermal TJ barrier was disrupted by sodium caprate treatment, Ca 2+ flux increased and the gradient changed in ion-capture cytochemistry images. Alterations of ultrastructures and proliferation/differentiation markers revealed that both hyperproliferation and precocious differentiation occurred regionally in the epidermis. These results suggest that the TJ plays a crucial role in maintaining epidermal homeostasis by controlling the Ca 2+ gradient.
IRPHE/B and W-SS-LATTICE, Spectral Shift Reactor Lattice Experiments
International Nuclear Information System (INIS)
2003-01-01
plutonium utilisation in commercial reactors. A fourth report concerns Critical Experiments Supporting Close Proximity Water Storage of Power Reactor Fuel. The fifth report concerns critical experiments supporting underwater storage of tightly packed configurations of spent fuel pins. The sixth report entitled 'Physics verification program', covers principally a series of experiments to measure the effect of lattice heterogeneities. The seventh report concerns Development and Demonstration of an Advanced Extended-Burnup Fuel- Assembly Design Incorporating Urania-Gadolinia. The eighth report concerns 'Urania-Gadolinia: Nuclear Model Development and Critical Experiment Benchmark'. The purpose was development and verification within an extended-burnup program for pressurised water reactors of advanced fuel assembly design. The ninth report concerns the Characterization and Irradiation Program: Extended-Burnup Gadolinia Lead Test Assembly (Mark GdB). The goal of the program was to extend the burnup of pressurized water reactor fuel assemblies to 50,000 MWd/mtU batch average burnup. The tenth report concerns the Hot Cell Examination of Gadolinia Lead Test Assembly Rods After One Cycle of Irradiation as described in the eighth and ninth report. The eleventh report covering April 1986 through March 1987, combines the progress report for the program entitled Development of an Advanced Extended Burnup Fuel Assembly Design Incorporating Urania-Gadolinia, and the final progress report for the program entitled Qualification of the B and W Mark B Fuel Assembly for High Burnup. The twelfth report describes five lead test assemblies designed, manufactured, characterized, and inserted for irradiation in Oconee Unit 1 cycle 8
Computers for lattice field theories
International Nuclear Information System (INIS)
Iwasaki, Y.
1994-01-01
Parallel computers dedicated to lattice field theories are reviewed with emphasis on the three recent projects, the Teraflops project in the US, the CP-PACS project in Japan and the 0.5-Teraflops project in the US. Some new commercial parallel computers are also discussed. Recent development of semiconductor technologies is briefly surveyed in relation to possible approaches toward Teraflops computers. (orig.)
Synthesis of spatially variant lattices.
Rumpf, Raymond C; Pazos, Javier
2012-07-02
It is often desired to functionally grade and/or spatially vary a periodic structure like a photonic crystal or metamaterial, yet no general method for doing this has been offered in the literature. A straightforward procedure is described here that allows many properties of the lattice to be spatially varied at the same time while producing a final lattice that is still smooth and continuous. Properties include unit cell orientation, lattice spacing, fill fraction, and more. This adds many degrees of freedom to a design such as spatially varying the orientation to exploit directional phenomena. The method is not a coordinate transformation technique so it can more easily produce complicated and arbitrary spatial variance. To demonstrate, the algorithm is used to synthesize a spatially variant self-collimating photonic crystal to flow a Gaussian beam around a 90° bend. The performance of the structure was confirmed through simulation and it showed virtually no scattering around the bend that would have arisen if the lattice had defects or discontinuities.
From lattice gases to polymers
Frenkel, D.
1990-01-01
The modification of a technique that was developed to study time correlations in lattice-gas cellular automata to facilitate the numerical simulation of chain molecules is described. As an example, the calculation of the excess chemical potential of an ideal polymer in a dense colloidal
Flavor extrapolation in lattice QCD
International Nuclear Information System (INIS)
Duffy, W.C.
1984-01-01
Explicit calculation of the effect of virtual quark-antiquark pairs in lattice QCD has eluded researchers. To include their effect explicitly one must calculate the determinant of the fermion-fermion coupling matrix. Owing to the large number of sites in a continuum limit size lattice, direct evaluation of this term requires an unrealistic amount of computer time. The effect of the virtual pairs can be approximated by ignoring this term and adjusting lattice couplings to reproduce experimental results. This procedure is called the valence approximation since it ignores all but the minimal number of quarks needed to describe hadrons. In this work the effect of the quark-antiquark pairs has been incorporated in a theory with an effective negative number of quark flavors contributing to the closed loops. Various particle masses and decay constants have been calculated for this theory and for one with no virtual pairs. The author attempts to extrapolate results towards positive numbers of quark flavors. The results show approximate agreement with experimental measurements and demonstrate the smoothness of lattice expectations in the number of quark flavors
Nuclear physics on the lattice?
International Nuclear Information System (INIS)
Koonin, S.E.
1985-01-01
The goal of the paper is to try to adapt lattice gauge theory to build in some biases in order for being applicable to nuclear physics. In so doing the calculations are made more precise, and the author can address questions like the size of the nucleon, the nucleon-nucleon potential, the modifications of the nucleon in the nuclear medium, etc. (Auth.)
Differential geometry of group lattices
International Nuclear Information System (INIS)
Dimakis, Aristophanes; Mueller-Hoissen, Folkert
2003-01-01
In a series of publications we developed ''differential geometry'' on discrete sets based on concepts of noncommutative geometry. In particular, it turned out that first-order differential calculi (over the algebra of functions) on a discrete set are in bijective correspondence with digraph structures where the vertices are given by the elements of the set. A particular class of digraphs are Cayley graphs, also known as group lattices. They are determined by a discrete group G and a finite subset S. There is a distinguished subclass of ''bicovariant'' Cayley graphs with the property ad(S)S subset of S. We explore the properties of differential calculi which arise from Cayley graphs via the above correspondence. The first-order calculi extend to higher orders and then allow us to introduce further differential geometric structures. Furthermore, we explore the properties of ''discrete'' vector fields which describe deterministic flows on group lattices. A Lie derivative with respect to a discrete vector field and an inner product with forms is defined. The Lie-Cartan identity then holds on all forms for a certain subclass of discrete vector fields. We develop elements of gauge theory and construct an analog of the lattice gauge theory (Yang-Mills) action on an arbitrary group lattice. Also linear connections are considered and a simple geometric interpretation of the torsion is established. By taking a quotient with respect to some subgroup of the discrete group, generalized differential calculi associated with so-called Schreier diagrams are obtained
Lattice dynamics of lithium oxide
Indian Academy of Sciences (India)
Abstract. Li2O finds several important technological applications, as it is used in solid- state batteries, can be used as a blanket breeding material in nuclear fusion reactors, etc. Li2O exhibits a fast ion phase, characterized by a thermally induced dynamic disorder in the anionic sub-lattice of Li+, at elevated temperatures ...
Lattice fields and strong interactions
International Nuclear Information System (INIS)
Creutz, M.
1989-06-01
I review the lattice formulation of gauge theories and the use of numerical methods to investigate nonperturbative phenomena. These methods are directly applicable to studying hadronic matter at high temperatures. Considerable recent progress has been made in numerical algorithms for including dynamical fermions in such calculations. Dealing with a nonvanishing baryon density adds new unsolved challenges. 33 refs
Borgs, C.; Chayes, J.T.; Hofstad, van der R.W.; Slade, G.
1999-01-01
We introduce a mean-field model of lattice trees based on embeddings into d of abstract trees having a critical Poisson offspring distribution. This model provides a combinatorial interpretation for the self-consistent mean-field model introduced previously by Derbez and Slade [9], and provides an