Fluid–particle flow simulations using two-way-coupled mesoscale SPH–DEM and validation
Robinson, M.J.; Luding, S.; Ramaioli, Marco
2013-01-01
First, a meshless simulation method is presented for multiphase fluid–particle flows with a two-way coupled Smoothed Particle Hydrodynamics (SPH) for the fluid and the Discrete Element Method (DEM) for the solid phase. The unresolved fluid model, based on the locally averaged Navier Stokes equations
Fluid-particle flow and validation using two-way-coupled mesoscale SPH-DEM
Robinson, Martin; Luding, Stefan; Ramaioli, Marco
2013-01-01
First, a meshless simulation method is presented for multiphase fluid-particle flows with a two-way coupled Smoothed Particle Hydrodynamics (SPH) for the fluid and the Discrete Element Method (DEM) for the solid phase. The unresolved fluid model, based on the locally averaged Navier Stokes equations, is expected to be considerably faster than fully resolved models. Furthermore, in contrast to similar mesh-based Discrete Particle Methods (DPMs), our purely particle-based method enjoys the flex...
Accurate calculation of Stokes drag for point-particle tracking in two-way coupled flows
Horwitz, Jeremy
2015-01-01
In this work, we propose and test a method for calculating Stokes drag applicable to particle-laden fluid flows where two-way momentum coupling is important. In the point-particle formulation, particle dynamics are coupled to fluid dynamics via a source term that appears in the respective momentum equations. When the particle Reynolds number is small and the particle diameter is smaller than the fluid scales, it is common to approximate the momentum coupling source term as the Stokes drag. The Stokes drag force depends on the difference between the undisturbed fluid velocity evaluated at the particle location, and the particle velocity. However, owing to two-way coupling, the fluid velocity is modified in the neighborhood of a particle, relative to its undisturbed value. This causes the computed Stokes drag force to be underestimated in two-way coupled point-particle simulations. We develop estimates for the drag force error as function of the particle size relative to the grid size. We then develop a correct...
Fluid-particle flow modelling and validation using two-way-coupled mesoscale SPH-DEM
Robinson, Martin; Ramaioli, Marco
2013-01-01
We present a meshless simulation method for multiphase fluid-particle flows coupling Smoothed Particle Hydrodynamics (SPH) and the Discrete Element Method (DEM). Rather than fully resolving the interstitial fluid, which is often infeasible, the unresolved fluid model is based on the locally averaged Navier Stokes equations, which are coupled with a DEM model for the solid phase. In contrast to similar mesh-based Discrete Particle Methods (DPMs), this is a purely particle-based method and enjoys the flexibility that comes from the lack of a prescribed mesh. It is suitable for problems such as free surface flow or flow around complex, moving and/or intermeshed geometries. It can be used for both one and two-way coupling and is applicable to both dilute and dense particle flows. A comprehensive validation procedure for fluid-particle simulations is presented and applied to the SPH-DEM method, using simulations of single and multiple particle sedimentation in a 3D fluid column and comparison with analytical model...
Chiu, Eddy
2012-01-01
In this paper, we consider linear MIMO transceiver design for a cellular two-way amplify-and-forward relaying system consisting of a single multi-antenna base station, a single multi-antenna relay station, and multiple multi-antenna mobile stations (MSs). Due to the two-way transmission, the MSs could suffer from tremendous multi-user interference. We apply an interference management model exploiting signal space alignment and propose a transceiver design algorithm, which allows for alleviating the loss in spectral efficiency due to half-duplex operation and providing flexible performance optimization accounting for each user's quality of service priorities. Numerical comparisons to conventional two-way relaying schemes based on bidirectional channel inversion and spatial division multiple access-only processing show that the proposed scheme achieves superior error rate and average data rate performance.
An efficient parallel flow solver for two-way coupled turbulent flows with deformable bodies
Verzicco, Roberto; Spandan, Vamsi; Meschini, Valentina; Lohse, Detlef; de Tullio, Marco D.
2016-11-01
There are countless examples in Nature and technology in which a flow and a deformable structure interact dynamically and determine each other's behaviour. Among many, two contexts in which this is particularly relevant is in two-phase flows with finite size deformable bubbles or immiscible drops and in cardiovascular flows of heart valves and deformable vessels. Since the standard methods become terminally expensive when the number of deformable bodies become large or the set-up has a complex geometric configuration, in this work, we discuss a simple yet effective approach to cope with the above problems. The main ingredients are: i) an efficient Navier-Stokes solver, ii) an interaction potential approach for the dynamics of a deformable structure, iii) an immersed boundary procedure to deal with the geometrical complexity iv) a set of fluid/structure interaction approaches (strong or loose) and v) a simple and efficient parallelisation strategy to handle large-scale simulations. Several complex examples will be shown and discussed with the results validated either by ad-hoc experiments or by comparisons with results from the literature.
Khabbazibasmenj, Arash; Vorobyov, Sergiy A; Haardt, Martin
2012-01-01
Sum-rate maximization in two-way amplify-and-forward (AF) multiple-input multiple-output (MIMO) relaying belongs to the class of difference-of-convex functions (DC) programming problems. DC programming problems occur as well in other signal processing applications and are typically solved using different modifications of the branch-and-bound method. This method, however, does not have any polynomial time complexity guarantees. In this paper, we show that a class of DC programming problems, to which the sum-rate maximization in two-way MIMO relaying belongs, can be solved very efficiently in polynomial time, and develop two algorithms. The objective function of the problem is represented as a product of quadratic ratios and parameterized so that its convex part (versus the concave part) contains only one (or two) optimization variables. One of the algorithms is called POlynomial-Time DC (POTDC) and is based on semi-definite programming (SDP) relaxation, linearization, and an iterative search over a single para...
Two-Way Interactions Between Equatorially-Trapped Waves and the Barotropic Flow
James FERGUSON; Boualem KHOUIDER; Maryam NAMAZI
2009-01-01
Lateral energy exchange between the tropics and the midlatitudes is a topic of great importance for understanding Earth's climate system.In this paper,the authors address this issue in an idealized set up through simple shallow water models for the interactions between equatorially trapped waves and the barotropic mode,which supports Rossby waves that propagate poleward and can excite midlatitude teleconnection patterns.It is found here that the interactions between a Kelvin wave and a fixed meridional shear (mimicking the jet stream) generates a non-trivial meridional velocity and meridional convergence in phase with the upward motion that can attain a maximum of about 50%,which oscillates on frequencies ranging from one day to 10 days.When,on the other hand,the barotropic flow is forced by slowly propagating Kelvin waves a complex flow pattern emerges:it consists of a phase-locked barotropic response that is equatorially trapped and that propagates eastward with the forcing Kelvin wave and a certain number of planetary Rossby waves that propagate westward and toward the poles as seen in nature.It is suggested here that the poleward propagating waves are to some sort of multi-way resonant interaction with the phase locked response.Moreover,it is shown here that a numerical scheme with dispersion properties that depend on the direction perpendicular to the direction of propagation,namely the 2D central scheme of Nessyahu and Tadmor,can artificially alter significantly the topology of the wave fields and thus should be avoided in climate models.
Smith, Timothy; Lu, Xiaoyi; Ranjan, Reetesh; Pantano, Carlos
2016-11-01
We describe a two-way coupled turbulent dispersed flow computational model using a high-order kernel density function (KDF) method. The carrier-phase solution is obtained using a high-order spatial and temporal incompressible Navier-Stokes solver while the KDF dispersed-phase solver uses the high-order Legendre WENO method. The computational approach is used to model carrier-phase turbulence modulation by the dispersed phase, and particle dispersion by turbulence as a function of momentum coupling strength (particle loading) and number of KDF basis functions. The use of several KDF's allows the model to capture statistical effects of particle trajectory crossing to high degree. Details of the numerical implementation and the coupling between the incompressible flow and dispersed-phase solvers will be discussed, and results at a range of Reynolds numbers will be presented. This work was supported by the National Science Foundation under Grant DMS-1318161.
Chen, Chun; Zhao, Bin; Yang, Xudong
2011-02-28
Maintaining positive pressure indoors using mechanical ventilation system is a popular control method for preventing the entry of outdoor airborne particles. The idea is, as long as the supply air flow rate is larger than return air flow rate, the pressure inside the ventilated room should be positive since the superfluous air flow must exfiltrate from air leakages or other openings of the room to the outdoors. Based on experimental and theoretical analyses this paper aims to show the impact of two-way air flow due to indoor/outdoor temperature difference on preventing the entry of outdoor particles using positive pressure control method. The indoor positive pressure control method is effective only when the size of the opening area is restricted to a certain level, opening degree less than 30° in this study, due to the two-way air flow effect induced by differential temperature. The theoretical model was validated using the experimental data. The impacts of two-way air flow due to temperature difference and the supply air flow rate were also analyzed using the theoretical model as well as experimental data. For real houses, it seems that the idea about the positive pressure control method for preventing the entry of outdoor particles has a blind side.
Ji Pei
2016-04-01
Full Text Available Axial-flow pump with a two-way passage has been widely employed in irrigation and drainage projects. Because of the shape of the two-way inlet passage, the impeller easily induces vibration due to unstable turbulent flow. This vibration results in structural cracks and even hinders the safe operation of the pump. Deformation and stress distributions in the impeller were calculated using two-way coupled fluid–structure interaction simulations, and a quantitative analysis of blade deformation and stress is carried out to determine the structure critical region. The results show that the values of deformation and stress significantly decrease with an increasing flow rate and a decreasing head, and the maximum total deformation can be found in the impeller rim, while the maximum equivalent stress can be obtained near the impeller hub. The total deformations in the blade rim decrease from blade leading edge to trailing edge, and the equivalent stress in the blade hub initially increases and then declines, and in the end, it rapidly increases from the blade outlet to inlet. These results reveal the deformation and stress in the impeller to ensure reliability and specific theoretical guidance for the structural optimization design of a pump device.
Czechowicz, K.; Badur, J.; Narkiewicz, K.
2014-08-01
Flow parameters can induce pathological changes in the arteries. We propose a method to asses those parameters using a 3D computer model of the flow in the Common Carotid Artery. Input data was acquired using an automatic 2D ultrasound wall tracking system. This data has been used to generate a 3D geometry of the artery. The diameter and wall thickness have been assessed individually for every patient, but the artery has been taken as a 75mm straight tube. The Young's modulus for the arterial walls was calculated using the pulse pressure, diastolic (minimal) diameter and wall thickness (IMT). Blood flow was derived from the pressure waveform using a 2-parameter Windkessel model. The blood is assumed to be non-Newtonian. The computational models were generated and calculated using commercial code. The coupling method required the use of Arbitrary Lagrangian-Euler formulation to solve Navier-Stokes and Navier-Lame equations in a moving domain. The calculations showed that the distention of the walls in the model is not significantly different from the measurements. Results from the model have been used to locate additional risk factors, such as wall shear stress or circumferential stress, that may predict adverse hypertension complications.
Sun, Guangyuan; Lignell, David; Hewson, John; Gin, Craig
2013-11-01
We present three algorithms (type-I, type-C and type-IC) for Lagrangian particle transport within the context of the one-dimensional turbulence (ODT) approach. ODT is a stochastic model that captures the full range of length and time scales and provides statistical information on fine-scale turbulent-particle mixing and transport at low computational cost. Two of the particle transport algorithms are new as is an algorithm to provide two-way momentum and energy coupling between the particle and carrier phases. Using these methods we investigate particle-laden turbulent jet flow. In contrast to other previous particle implementation in ODT, the two new methods allow the particles to interact with multiple eddies simultaneously and evolve the particle phase continuously, and therefore are able to accurately capture turbulent mixing and fluctuation seen by inertial particles in ODT. Simulation results are compared with experimental data including the effect of two particle Stokes numbers (St = 3.6 and 10.8). Turbulence modification, particle number density PDFs and particle velocity evolution are presented.
Viscosity and density dependence during maximal flow in man.
Staats, B A; Wilson, T A; Lai-Fook, S J; Rodarte, J R; Hyatt, R E
1980-02-01
Maximal expiratory flow curves were obtained from ten healthy subjects white breathing air and three other gas mixtures with different densities and viscosities. From these data, the magnitudes of the dependence of maximal flow on gas density and viscosity were obtained. The scaling laws of fluid mechanics, together with a model for the flow-limiting mechanism, were used to obtain a prediction of the relationship between the density dependence and the viscosity dependence of maximal flow. Although the data for individual subjects were too variable to allow a precise comparison with this prediction, the relationship between the mean density dependence and the mean viscosity dependence of all usbjects agreed with the theoretic prediction. This agreement supports the assumption, which is frequently made, that flow resistance rather than tissue visoelasticity is the dominant contributor to peripheral resistance. Information on the relationships between the pressure drop to the flow-limiting segment and flow, gas density and viscosity, and lung volume were also obtained.
What Do Consumers' Fund Flows Maximize?
Christoffersen, Susan; Evans, Richard; Musto, David K.
2013-01-01
We ask whether mutual funds’ flows reflect the incentives of the brokers intermediating them. The incentives we address are those revealed in statutory filings: the brokers’ shares of sales loads and other revenue, and their affiliation with the fund family. We find significant effects of these p......We ask whether mutual funds’ flows reflect the incentives of the brokers intermediating them. The incentives we address are those revealed in statutory filings: the brokers’ shares of sales loads and other revenue, and their affiliation with the fund family. We find significant effects...... of these payments to brokers on funds’ inflows, particularly when the brokers are not affiliated. Tracking these investments forward, we find load sharing, but not revenue sharing, to predict poor performance, consistent with the different incentives these payments impart. We identify one benefit of captive...
Maximal expiratory flow volume curve in quarry workers.
Subhashini, Arcot Sadagopa; Satchidhanandam, Natesa
2002-01-01
Maximal Expiratory Flow Volume (MEFV) curves were recorded with a computerized Spirometer (Med Spiror). Forced Vital Capacity (FVC), Forced Expiratory Volumes (FEV), mean and maximal flow rates were obtained in 25 quarry workers who were free from respiratory disorders and 20 healthy control subjects. All the functional values are lower in quarry workers than in the control subject, the largest reduction in quarry workers with a work duration of over 15 years, especially for FEF75. The effects are probably due to smoking rather than dust exposure.
General spectral flow formula for fixed maximal domain
Booss-Bavnbek, Bernhelm; Zhu, Chaofeng
2005-01-01
We consider a continuous curve of linear elliptic formally self-adjoint differential operators of first order with smooth coefficients over a compact Riemannian manifold with boundary together with a continuous curve of global elliptic boundary value problems. We express the spectral flow...... of the resulting continuous family of (unbounded) self-adjoint Fredholm operators in terms of the Maslov index of two related curves of Lagrangian spaces. One curve is given by the varying domains, the other by the Cauchy data spaces. We provide rigorous definitions of the underlying concepts of spectral theory...... and symplectic analysis and give a full (and surprisingly short) proof of our General Spectral Flow Formula for the case of fixed maximal domain. As a side result, we establish local stability of weak inner unique continuation property (UCP) and explain its role for parameter dependent spectral theory....
Random graph states, maximal flow and Fuss-Catalan distributions
Collins, BenoIt; Nechita, Ion [Department of Mathematics and Statistics, University of Ottawa, Ontario K1N8M2 (Canada); Zyczkowski, Karol [Institute of Physics, Jagiellonian University, ul. Reymonta 4, 30-059 Krakow (Poland)
2010-07-09
For any graph consisting of k vertices and m edges we construct an ensemble of random pure quantum states which describe a system composed of 2m subsystems. Each edge of the graph represents a bipartite, maximally entangled state. Each vertex represents a random unitary matrix generated according to the Haar measure, which describes the coupling between subsystems. Dividing all subsystems into two parts, one may study entanglement with respect to this partition. A general technique to derive an expression for the average entanglement entropy of random pure states associated with a given graph is presented. Our technique relies on Weingarten calculus and flow problems. We analyze the statistical properties of spectra of such random density matrices and show for which cases they are described by the free Poissonian (Marchenko-Pastur) distribution. We derive a discrete family of generalized, Fuss-Catalan distributions and explicitly construct graphs which lead to ensembles of random states characterized by these novel distributions of eigenvalues.
Random graph states, maximal flow and Fuss-Catalan distributions
Collins, Benoit; Zyczkowski, Karol
2010-01-01
For any graph consisting of $k$ vertices and $m$ edges we construct an ensemble of random pure quantum states which describe a system composed of $2m$ subsystems. Each edge of the graph represents a bi-partite, maximally entangled state. Each vertex represents a random unitary matrix generated according to the Haar measure, which describes the coupling between subsystems. Dividing all subsystems into two parts, one may study entanglement with respect to this partition. A general technique to derive an expression for the average entanglement entropy of random pure states associated to a given graph is presented. Our technique relies on Weingarten calculus and flow problems. We analyze statistical properties of spectra of such random density matrices and show for which cases they are described by the free Poissonian (Marchenko-Pastur) distribution. We derive a discrete family of generalized, Fuss-Catalan distributions and explicitly construct graphs which lead to ensembles of random states characterized by thes...
Maximizing Flow in the Secondary Social Science Classroom.
Enriquez, Nicole Christian
First introduced in the early 1990s, the flow theory of Mihaly Csikszentmihalyi, giving much attention to motivation and how it relates to learning, has presented a new view for educators to apply in their classrooms. Csikszentmihalyi suggests that the most effective learning in a classroom will happen when students have entered "flow."…
Assigning on-ramp flows to maximize highway capacity
Wang, Qiao-Ming; Jiang, Rui; Sun, Xiao-Yan; Wang, Bing-Hong
2009-09-01
In this paper, we study the capacity of a highway with two on-ramps by using a cellular automata traffic flow model. We investigate how to improve the system capacity by assigning traffic flow to the two ramps. The system phase diagram is presented and different regions are classified. It is shown that in region I, in which both ramps are in free flow and the main road upstream of the ramps is in congestion, assigning a higher proportion of the demand to the upstream on-ramp could improve the overall flow, which is consistent with previous studies. This is explained through studying the spatiotemporal patterns and analytical investigations. In contrast, optimal assignment has not been observed in other regions. We point out that our result is robust and model independent under certain conditions.
Austin, R E; Aldea, G S; Coggins, D L; Flynn, A E; Hoffman, J I
1990-08-01
We examined the ability of individual regions of the canine left ventricle to increase blood flow relative to baseline rates of perfusion. Regional coronary flow was measured by injecting radioactive microspheres over 90 seconds in seven anesthetized mongrel dogs. Preliminary experiments demonstrated a correlation between the regional distributions of blood flow during asphyxia and pharmacological vasodilatation with adenosine (mean r = 0.75; 192 regions in each of two dogs), both of which resulted in increased coronary flow. Subsequent experiments, during which coronary perfusion pressure was held constant at 80 mm Hg, examined the pattern of blood flow in 384 regions (mean weight, 106 mg) of the left ventricular free wall during resting flow and during maximal coronary flow effected by intracoronary adenosine infusion. We found that resting and maximal flow patterns were completely uncorrelated to each other in a given dog (mean r = 0.06, p = NS; n = 3 dogs). Furthermore, regional coronary reserve, defined as the ratio of maximal to resting flow, ranged from 1.75 (i.e., resting flow was 57% of maximum) to 21.9 (resting flow was 4.5% of maximum). Thus, coronary reserve is spatially heterogeneous and determined by two distinct perfusion patterns: the resting (control) pattern and the maximal perfusion pattern. Normal hearts, therefore, contain small regions that may be relatively more vulnerable to ischemia. This may explain the patchy nature of infarction with hypoxia and at reduced perfusion pressures as well as the difficulty of using global parameters to predict regional ischemia. Despite the wide dispersion of coronary reserve, we found, by autocorrelation analysis, that reserve in neighboring regions (even when separated by a distance of several tissue samples) was significantly correlated. This also applied to patterns of resting myocardial flow. Thus, both resting coronary blood flow and reserve appear to be locally continuous and may define functional
Two-Way communication with energy exchange
Popovski, Petar; Simeone, Osvaldo
2012-01-01
The conventional assumption made in the design of communication systems is that the energy used to transfer information between a sender and a recipient cannot be reused for future communication tasks. A notable exception to this norm is given by passive RFID systems, in which a reader can transfer...... both information and energy via the transmitted radio signal. Conceivably, any system that exchanges information via the transfer of given physical resources (radio waves, particles, qubits) can potentially reuse, at least part, of the received resources for communication later on. In this paper, a two......-way communication system is considered that operates with a given initial number of physical resources, referred to as energy units. The energy units are not replenished from outside the system, and are assumed, for simplicity, to be constant over time. A node can either send an “on” symbol (or “1”), which costs...
Two-way quantum communication channels
Childs, A M; Lo, H K; Childs, Andrew M.; Leung, Debbie W.; Lo, Hoi-Kwong
2005-01-01
We consider communication between two parties using a bipartite quantum operation, which constitutes the most general quantum mechanical model of two-party communication. We primarily focus on the simultaneous forward and backward communication of classical messages. For the case in which the two parties share unlimited prior entanglement, we give inner and outer bounds on the achievable rate region that generalize classical results due to Shannon. In particular, using a protocol of Bennett, Harrow, Leung, and Smolin, we give a one-shot expression in terms of the Holevo information for the entanglement-assisted one-way capacity of a two-way quantum channel. As applications, we rederive two known additivity results for one-way channel capacities: the entanglement-assisted capacity of a general one-way channel, and the unassisted capacity of an entanglement-breaking one-way channel.
TWO-WAY ROAD NETWORK DESIGN PROBLEM WITH VARIABLE LANES
Haozhi ZHANG; Ziyou GAO
2007-01-01
This paper studies a new form of transportation network design problem.In urban transportation network,unreasonable phenomenon can occur in certain traffic period (e.g.on/off duty period),which demonstrates that the flows of opposite directions on a two-way road are seriously asymmetric; one traffic link of a two-way road congest heavily but the other is hardly used.In order to reduce transportation congestion and make full use of the existing road resources,we propose a lane reallocating approach in peak period,and establish a discrete bi-level programming model for the decision-making.Then,based on particle swarm optimization (PSO) technique,a heuristic solution algorithm for the bi-level model is designed.Finally,the lane reallocating approach is demonstrated through a simple transportation network.
Translational Medicine: A two-way road
Marincola Francesco M
2003-07-01
Full Text Available Abstract The purpose of translational research is to test, in humans, novel therapeutic strategies developed through experimentation. Translational research should be regarded as a two-way road: Bench to Bedside and Bedside to Bench. However, Bedside to Bench efforts have regrettably been limited because the scientific aspects are poorly understood by full time clinicians and the difficulty of dealing with humans poorly appreciated by basic scientists. Translational research would be most useful to the scientific community at large if journals would foster specific interest for the publication of ex vivo human observation. The review process for such work should be assigned to clinical scientists competent not only in the intricacies of molecular or cell biology but also intimate with the reality of Internal Review Boards, ethics committees, Governmental Regulatory Agencies and most importantly the humane aspects of dealing with sick individuals and their families. This approach may focus both basic and clinical scientists and those struggling to fill the gap between them on the effective treatment of diseases affecting women, men and children making translational research more than an interesting concept.
Two-way cable television system characterization
Schauer, Paul T.
1995-11-01
This presentation is a report of the testing activities of the CableLabs Network Integrity Working Group. The working group consisted of several CableLabs member companies which conducted rf analog and digital bit-error testing at five CATV networks in the U.S. and Canada. The purpose of the working group was to measure the reliability and availability of the contemporary CATV network as specified by traditional switched access telephony performance parameters. Transmission data was collected for both forward and reverse (sub- split) paths of the rf broadband network, in both traditional and hybrid fiber/coax architectures, and for baseline and controlled variation events. The basic premise of this testing was to ascertain which cable television network elements adversely affected transmission of a 'generic' digital communications system and how they can be managed or controlled. The digital transmission utilized in the test was a QPSK modulated, T-1 rate (1.544 Mbit/second), modem without error correction. The intent was not to derive the necessary modulation technique and error correction scheme to properly operate in every cable television system, but rather to determine the principal sources of impairments existing in these networks and deduce corrective measures. The full report of the Network Integrity Working Group is published by CableLabs, Inc., and is titled, 'Two-Way Cable Television System Characterization -- Final Report', April 1995.
The Analysis of Two-Way Functional Data Using Two-Way Regularized Singular Value Decompositions
Huang, Jianhua Z.
2009-12-01
Two-way functional data consist of a data matrix whose row and column domains are both structured, for example, temporally or spatially, as when the data are time series collected at different locations in space. We extend one-way functional principal component analysis (PCA) to two-way functional data by introducing regularization of both left and right singular vectors in the singular value decomposition (SVD) of the data matrix. We focus on a penalization approach and solve the nontrivial problem of constructing proper two-way penalties from oneway regression penalties. We introduce conditional cross-validated smoothing parameter selection whereby left-singular vectors are cross- validated conditional on right-singular vectors, and vice versa. The concept can be realized as part of an alternating optimization algorithm. In addition to the penalization approach, we briefly consider two-way regularization with basis expansion. The proposed methods are illustrated with one simulated and two real data examples. Supplemental materials available online show that several "natural" approaches to penalized SVDs are flawed and explain why so. © 2009 American Statistical Association.
McNeil, Chris J; Allen, Matti D; Olympico, Eric; Shoemaker, J Kevin; Rice, Charles L
2015-09-01
A reduction of blood flow to active muscle will precipitate fatigue, and sustained isometric contractions produce intramuscular and compartmental pressures that can limit flow. The present study explored how blood flow and muscle oxygenation respond to isometric contractions at low, moderate, and maximal intensities. Over two visits, 10 males (26 ± 2 yr; means ± SD) performed 1-min dorsiflexion contractions at 30, 60, and 100% of maximal voluntary contraction (MVC) torque. Doppler ultrasound of the anterior tibial artery was used to record arterial diameter and mean blood velocity and to calculate absolute blood flow. The tissue oxygenation index (TOI) of tibialis anterior was acquired with near-infrared spectroscopy (NIRS). There was a progressive increase in blood flow at 30% MVC (peak of 289 ± 139% resting value), no change from rest until an increase in the final 10 s of exercise at 60% MVC (peak of 197 ± 102% rest), and an initial decrease (59 ± 30% resting value) followed by a progressive increase at 100% MVC (peak of 355 ± 133% rest). Blood flow was greater at 30 and 100% than 60% MVC during the last 30 s of exercise. TOI was ∼63% at rest and, within 30 s of exercise, reached steady-state values of ∼42%, ∼22%, and ∼22% for 30, 60, and 100% MVC, respectively. Even maximal contraction of the dorsiflexors is unable to cause more than a transient decrease of flow in the anterior tibial artery. Unlike dynamic or intermittent isometric exercise, our results indicate blood flow is not linearly graded with intensity or directly coupled with oxygenation during sustained isometric contractions.
Wall, M A; Olson, D; Bonn, B A; Creelman, T; Buist, A S
1982-02-01
Reference standards of lung function was determined in 176 healthy North American Indian children (94 girls, 82 boys) 7 to 18 yr of age. Spirometry, maximal expiratory flow volume curves, and peak expiratory flow rate were measured using techniques and equipment recommended by the American Thoracic Society. Standing height was found to be an accurate predictor of lung function, and prediction equations for each lung function variable are presented using standing height as the independent variable. Lung volumes and expiratory flow rates in North American Indian children were similar to those previously reported for white and Mexican-American children but were greater than those in black children. In both boys and girls, lung function increased in a curvilinear fashion. Volume-adjusted maximal expiratory flow rates after expiring 50 or 75% of FVC tended to decrease in both sexes as age and height increased. Our maximal expiratory flow volume curve data suggest that as North American Indian children grow, lung volume increases at a slightly faster rate than airway size does.
Poker, Gilad; Zarai, Yoram; Margaliot, Michael; Tuller, Tamir
2014-11-06
Translation is an important stage in gene expression. During this stage, macro-molecules called ribosomes travel along the mRNA strand linking amino acids together in a specific order to create a functioning protein. An important question, related to many biomedical disciplines, is how to maximize protein production. Indeed, translation is known to be one of the most energy-consuming processes in the cell, and it is natural to assume that evolution shaped this process so that it maximizes the protein production rate. If this is indeed so then one can estimate various parameters of the translation machinery by solving an appropriate mathematical optimization problem. The same problem also arises in the context of synthetic biology, namely, re-engineer heterologous genes in order to maximize their translation rate in a host organism. We consider the problem of maximizing the protein production rate using a computational model for translation-elongation called the ribosome flow model (RFM). This model describes the flow of the ribosomes along an mRNA chain of length n using a set of n first-order nonlinear ordinary differential equations. It also includes n + 1 positive parameters: the ribosomal initiation rate into the mRNA chain, and n elongation rates along the chain sites. We show that the steady-state translation rate in the RFM is a strictly concave function of its parameters. This means that the problem of maximizing the translation rate under a suitable constraint always admits a unique solution, and that this solution can be determined using highly efficient algorithms for solving convex optimization problems even for large values of n. Furthermore, our analysis shows that the optimal translation rate can be computed based only on the optimal initiation rate and the elongation rate of the codons near the beginning of the ORF. We discuss some applications of the theoretical results to synthetic biology, molecular evolution, and functional genomics.
Multi-compartment approach to identify minimal flow and maximal recreational use of a lowland river
Pusch, Martin; Lorenz, Stefan
2013-04-01
Most approaches to establish a minimum flow rate for river sections subjected to water abstraction focus on flow requirements of fish and benthic invertebrates. However, artificial reduction of river flow will always affect additional key ecosystem features, as sediment properties and the metabolism of matter in these ecosystems as well, and may even influence adjacent floodplains. Thus, significant effects e.g. on the dissolved oxygen content of river water, on habitat conditions in the benthic zone, and on water levels in the floodplain are to be expected. Thus, we chose a multiple compartment method to identify minimum flow requirements in a lowland River in northern Germany (Spree River), selecting the minimal required flow level out of all compartments studied. Results showed that minimal flow levels necessary to keep key ecosystem features at a 'good' state depended significantly on actual water quality and on river channel morphology. Thereby, water quality of the Spree is potentially influenced by recreational boating activity, which causes mussels to stop filter-feeding, and thus impedes self-purification. Disturbance of mussel feeding was shown to directly depend on boat type and speed, with substantial differences among mussel species. Thus, a maximal recreational boating intensity could be derived that does not significantly affect self purification. We conclude that minimal flow levels should be identified not only based on flow preferences of target species, but also considering channel morphology, ecological functions, and the intensity of other human uses of the river section.
Maximal expiratory and inspiratory flow-volume curves in Parkinson's disease.
Bogaard, J M; Hovestadt, A; Meerwaldt, J; vd Meché, F G; Stigt, J
1989-03-01
In order to investigate the type and degree of upper airway obstruction (UAO) in a group of patients with Parkinson's disease in different stages of the disease, we obtained maximal expiratory and inspiratory flow-volume (MEFV and MIFV) curves and maximal static mouth pressures. The clinical disability was indicated by a Hoehn-Yahr (H-Y) scale, ranging from III to V, and a more continuous Northwestern University Disability Scale (NUDS), ranging from zero to 50. Twelve patients were in H-Y Group III, and eleven and eight were in Groups IV and V, respectively. The pattern of the flow-volume curves was classified as either normal, or with superimposed regular or irregular oscillations (A), or with rounded-off and delayed expiratory peak appearance (B). Mean MEFV curves in Groups III and IV were not appreciably different from reference. In Group V, the mean curve showed a lower peak expiratory flow (PEF) and a more convex tail. Only the effort-dependent variables PEF, peak inspiratory flow (PIF), and maximal mouth pressures at RV and TLC (PmTLC and PmRV) appeared to be significantly correlated with the NUDS index and decreased with increasing clinical disability. The mean values of those variables were also significantly different between the H-Y groups. The number of normal curves decreased from H-Y Group III to Group V. The contribution of A and B curves was relatively equal in the groups, with only a small number of A curves.(ABSTRACT TRUNCATED AT 250 WORDS)
Traffic Flow by Cellular Automata: the Effect of Maximal Car Velocity
Makowiecki, D S; Makowiec, Danuta; Miklaszewski, Wieslaw
2005-01-01
Effects of large value assigned to the maximal car velocity on the fundamental diagrams in the Nagel-Schreckenberg model are studied by extended simulations. The function relating the flow in the congested traffic phase with the car density and deceleration probability is found numerically. Properties of the region of critical changes, so-called jamming transition parameters, are described in details. The basic model, modified by the assumption that for each car an individual velocity limit is assigned, is investigated in the aim to find the best supplementary rule allowing the jammed traffic to move with velocity larger than the slowest driving vehicle.
S. T. Jaya Christa
2006-06-01
Full Text Available This paper deals with the optimal location and parameters of Unified Power Flow Controllers (UPFCs in electrical power systems, using particle swarm optimization (PSO. The objective is to maximize the transmission system loadability subject to the transmission line capacity limits and specified bus voltage levels. Using the proposed method, the location of UPFCs and their parameters are optimized simultaneously. PSO is used to solve the above non-linear programming problem for better accuracy. The proposed approach is examined and tested on IEEE 30-bus system and IEEE 118-bus system. The results obtained are quite promising for the power system operation environment
Maximizing run time performance of deployed data flow graphs on a multiprocessor architecture
Tobias, Richard J.; Hunt, Peter D.
1993-10-01
This paper discusses a practical solution for supporting the deployment of data flow graphs onto the Loral/Rolm Computer Systems, Inc. vector processing multi-processor architecture. It outlines the support software (both workstation hosted and target system hosted) that is required to design, debug, and maximize deployed data flow graph performance on the multiprocessor architecture. The deployment process guarantees real-time deadlines, minimizes run time scheduling overhead, and minimizes designer partitioning input. It is known that determining effective run time data flow graph node schedules for multi-processor architectures is an NP-complete class of problem not well suited to real-time systems. Loral/Rolm Computer Systems, Inc.'s vector processing toolset recognizes this problem and this paper discusses a prescheduling and pre-assignment approach for partitioning data flow graphs to available hardware resources. In particular the toolset components (which are based upon an enhanced data flow graph language) of workstation pre-assignment, prescheduling, run time gross allocation and local compute element dispatching are discussed in detail.
Two-Way Coupling Vortex Method and Its Application
无
1992-01-01
Because of the success of the discrete vortex method for the simulation of large-scale vortex structure.many researchers extend this method to two-phase flow simulations,especially,to the simulation of particle dispersion in mixing layer,which is characterized by large-scale vortex structure,But the previous work is limited to one-way couplin,which neglects the effect of particles on fluid flow.In this paper a discrete vortex method involving two-way coupling for two-phase flows is frist proposed and then used in numerical simulation of two-dimensional gas-particle mixin layers The numerical results show that the introduction of particles into the mixing layer has significant effects on the creation,development and merging process of large-scale vortex structures.It makes the mean size of large-scale vortex stucture large and the distance needed for development of large-scale vortex sturcture shorter.
Balance between noise and information flow maximizes set complexity of network dynamics.
Tuomo Mäki-Marttunen
Full Text Available Boolean networks have been used as a discrete model for several biological systems, including metabolic and genetic regulatory networks. Due to their simplicity they offer a firm foundation for generic studies of physical systems. In this work we show, using a measure of context-dependent information, set complexity, that prior to reaching an attractor, random Boolean networks pass through a transient state characterized by high complexity. We justify this finding with a use of another measure of complexity, namely, the statistical complexity. We show that the networks can be tuned to the regime of maximal complexity by adding a suitable amount of noise to the deterministic Boolean dynamics. In fact, we show that for networks with Poisson degree distributions, all networks ranging from subcritical to slightly supercritical can be tuned with noise to reach maximal set complexity in their dynamics. For networks with a fixed number of inputs this is true for near-to-critical networks. This increase in complexity is obtained at the expense of disruption in information flow. For a large ensemble of networks showing maximal complexity, there exists a balance between noise and contracting dynamics in the state space. In networks that are close to critical the intrinsic noise required for the tuning is smaller and thus also has the smallest effect in terms of the information processing in the system. Our results suggest that the maximization of complexity near to the state transition might be a more general phenomenon in physical systems, and that noise present in a system may in fact be useful in retaining the system in a state with high information content.
Bino, Gilad; Steinfeld, Celine; Kingsford, Richard T
2014-01-01
Global wetland biodiversity loss continues unabated, driven by increased demand for freshwater. A key strategy for conservation management of freshwater systems is to maintain the quantity and quality of the natural water regimes, including the frequency and timing of flows. Formalizing an ecological model depicting the key ecological components and the underlying processes of cause and effect is required for successful conservation management. Models linking hydrology with ecological responses can prove to be an invaluable tool for robust decision-making of environmental flows. Here, we explored alternative water management strategies and identified maximal strategies for successful long-term management of colonial waterbirds in the Macquarie Marshes, Australia. We modeled fluctuations in breeding abundances of 10 colonial waterbird species over the past quarter century (1986-2010). Clear relationships existed between flows and breeding, both in frequencies and total abundances, with a strong linear relationship for flows > 200 GL. Thresholds emerged for triggering breeding events in all 10 species, but these varied among species. Three species displayed a sharp threshold response between 100 GL and 250 GL. These had a breeding probability of 0.5 when flows were > 180 GL and a 0.9 probability of breeding with flows > 350 GL. The remaining species had a probability greater than 0.5 of breeding with flows > 400 GL. Using developed models, we examined the effects of five environmental flow management strategies on the variability of flows and subsequent likelihood of breeding. Management to different target volumes of environmental flows affected overall and specific breeding probabilities. The likelihood of breeding for all 10 colonial waterbirds increased from a regulated historical mean (+/-SD) of 0.36 +/- 0.09 to 0.53 +/- 0.14, an improvement of 47.5% +/- 18.7%. Management of complex ecosystems depends on good understanding of the responses of organisms to the
Maximizing Protein Translation Rate in the Ribosome Flow Model: The Homogeneous Case.
Zarai, Yoram; Margaliot, Michael; Tuller, Tamir
2014-01-01
Gene translation is the process in which intracellular macro-molecules, called ribosomes, decode genetic information in the mRNA chain into the corresponding proteins. Gene translation includes several steps. During the elongation step, ribosomes move along the mRNA in a sequential manner and link amino-acids together in the corresponding order to produce the proteins. The homogeneous ribosome flow model (HRFM) is a deterministic computational model for translation-elongation under the assumption of constant elongation rates along the mRNA chain. The HRFM is described by a set of n first-order nonlinear ordinary differential equations, where n represents the number of sites along the mRNA chain. The HRFM also includes two positive parameters: ribosomal initiation rate and the (constant) elongation rate. In this paper, we show that the steady-state translation rate in the HRFM is a concave function of its parameters. This means that the problem of determining the parameter values that maximize the translation rate is relatively simple. Our results may contribute to a better understanding of the mechanisms and evolution of translation-elongation. We demonstrate this by using the theoretical results to estimate the initiation rate in M. musculus embryonic stem cell. The underlying assumption is that evolution optimized the translation mechanism. For the infinite-dimensional HRFM, we derive a closed-form solution to the problem of determining the initiation and transition rates that maximize the protein translation rate. We show that these expressions provide good approximations for the optimal values in the n-dimensional HRFM already for relatively small values of n. These results may have applications for synthetic biology where an important problem is to re-engineer genomic systems in order to maximize the protein production rate.
Gooya, Ali; Liao, Hongen; Sakuma, Ichiro
2012-09-01
Geometric flux maximizing flow (FLUX) is an active contour based method which evolves an initial surface to maximize the flux of a vector field on the surface. For blood vessel segmentation, the vector field is defined as the vectors specified by vascular edge strengths and orientations. Hence, the segmentation performance depends on the quality of the detected edge vector field. In this paper, we propose a new method for level set based segmentation of blood vessels by generalizing the FLUX on a Riemannian manifold (R-FLUX). We consider a 3D scalar image I(x) as a manifold embedded in the 4D space (x, I(x)) and compute the image metric by pullback from the 4D space, whose metric tensor depends on the vessel enhancing diffusion (VED) tensor. This allows us to devise a non-linear filter which both projects and normalizes the original image gradient vectors under the inverse of local VED tensors. The filtered gradient vectors pertaining to the vessels are less sensitive to the local image contrast and more coherent with the local vessel orientation. The method has been applied to both synthetic and real TOF MRA data sets. Comparisons are made with the FLUX and vesselsness response based segmentations, indicating that the R-FLUX outperforms both methods in terms of leakage minimization and thiner vessel delineation.
Attractors, black objects and holographic RG flows in 5d maximal gauged supergravities
Hristov, Kiril; Rota, Andrea [Dipartimento di Fisica, Università di Milano-Bicocca,and INFN, sezione di Milano-Bicocca,I-20126 Milano (Italy)
2014-03-12
We perform a systematic search for static solutions in different sectors of 5d N=8 supergravities with compact and non-compact gauged R-symmetry groups, finding new and listing already known backgrounds. Due to the variety of possible gauge groups and resulting scalar potentials, the maximally symmetric vacua we encounter in these theories can be Minkowski, de Sitter, or anti-de Sitter. There exist BPS and non-BPS near-horizon geometries and full solutions with all these three types of asymptotics, corresponding to black holes, branes, strings, rings, and other black objects with more exotic horizon topologies, supported by U(1) and SU(2) charges. The asymptotically AdS{sub 5} solutions also have a clear holographic interpretation as RG flows of field theories on D3 branes, wrapped on compact 2- and 3-manifolds.
Cerebral blood flow during submaximal and maximal dynamic exercise in humans
Thomas, S N; Schroeder, T; Secher, N H
1989-01-01
Cerebral blood flow (CBF) in humans was measured at rest and during dynamic exercise on a cycle ergometer corresponding to 56% (range 27-85) of maximal O2 uptake (VO2max). Exercise bouts were performed by 16 male and female subjects, lasted 15 min each, and were carried out in a semisupine position....... CBF (133Xe clearance) was expressed as the initial slope index (ISI) and as the first compartment flow (F1). CBF at rest [ISI, 58 (range 45-73); F1, 76 (range 55-98) ml.100 g-1.min-1] increased during exercise [ISI to 79 (57-94) and F1 to 118 (75-164) ml.100 g-1.min-1, P less than 0.01]. CBF did...... not differ significantly between work loads from 32 (24-33) to 86% (74-96) of VO2max (n = 10). During exercise, mean arterial pressure increased from 84 (60-100) to 101 (78-124) Torr (P less than 0.01) and PCO2 remained unchanged [5.1 (4.6-5.6) vs. 5.4 (4.4-6.3) kPa, n = 6]. These results demonstrate...
Weston, Melissa C; Nash, Christena K; Homesley, Jerry J; Fritsch, Ingrid
2012-11-01
There is a need for a microfluidic pumping technique that is simple to fabricate, yet robust, compatible with a variety of solvents, and which has easily controlled fluid flow. Redox-magnetohydrodynamics (MHD) offers these advantages. However, the presence of high concentrations of redox species, important for inducing sufficient convection at low magnetic fields for hand-held devices, can limit the use of redox-MHD pumping for analytical applications. A new method for redox-MHD pumping is investigated that takes advantage of the large amplitude of the transient portion of the faradaic current response that occurs upon stepping the potential sufficiently past the standard electrode potential, E°, of the pumping redox species at an electrode. This approach increases the velocity of the fluid for a given redox concentration. An electronic switch was implemented between the potentiostat and electrochemical cell to alternately turn on and off different electrodes along the length of the flow path to maximize this transient electronic current and, as a result, the flow speed. Velocities were determined by tracking microbeads in a solution containing electroactive potassium ferrocyanide and potassium ferricyanide, and supporting electrolyte, potassium chloride, in the presence of a magnetic field. Fluid velocities with slight pulsation were obtained with the switch that were 70% faster than the smooth velocities without the switch. This indicates that redox species concentrations can be lowered by a similar amount to achieve a given speed, thereby diminishing interference of the redox species with detection of the analyte in applications of redox-MHD microfluidics for chemical analysis.
Achievable Rates for Two-Way Wire-Tap Channels
Tekin, Ender
2007-01-01
We consider two-way wire-tap channels, where two users are communicating with each other in the presence of an eavesdropper, who has access to the communications through a multiple-access channel. We find achievable rates for two different scenarios, the Gaussian two-way wire-tap channel, (GTW-WT), and the binary additive two-way wire-tap channel, (BATW-WT). It is shown that the two-way channels inherently provide a unique advantage for wire-tapped scenarios, as the users know their own transmitted signals and in effect help encrypt the other user's messages, similar to a one-time pad. We compare the achievable rates to that of the Gaussian multiple-access wire-tap channel (GMAC-WT) to illustrate this advantage.
Cross-Layer Optimization of Two-Way Relaying for Statistical QoS Guarantees
lin, Cen; Tao, Meixia
2012-01-01
Two-way relaying promises considerable improvements on spectral efficiency in wireless relay networks. While most existing works focus on physical layer approaches to exploit its capacity gain, the benefits of two-way relaying on upper layers are much less investigated. In this paper, we study the cross-layer design and optimization for delay quality-of-service (QoS) provisioning in two-way relay systems. Our goal is to find the optimal transmission policy to maximize the weighted sum throughput of the two users in the physical layer while guaranteeing the individual statistical delay-QoS requirement for each user in the datalink layer. This statistical delay-QoS requirement is characterized by the QoS exponent. By integrating the concept of effective capacity, the cross-layer optimization problem is equivalent to a weighted sum effective capacity maximization problem. We derive the jointly optimal power and rate adaptation policies for both three-phase and two-phase two-way relay protocols. Numerical results...
HOMEinTOUCH Designing two-way Ambient Communication
Petersen, Marianne Graves; Hansen, Aviaja Borup; Nielsen, Kaspar Rosengreen
2008-01-01
Digital Picture Frames has received attention both research wise and by consumers, who are increasingly buying existing solutions. In this paper we investigate how to design improved picture frames through providing means for two-way communication and through exploring the potential in providing...... automatically generated context information. We report on the design and trial use of a HOMEinTOUCH, an experience prototype of a picture frame for domestic environment, supporting two-way communication and context-information around pictures. We tested this prototype, as well as two other commercial products...
Yilmaz, Alper
2015-04-01
It is intended to design compact heat exchangers which can transfer high heat flow for a given volume and temperature difference with high efficiency. This work presents the optimal design of heat exchangers for a given length or hydraulic diameter with a constraint of a certain pressure loss and constant wall temperature. Both volumetric heat transfer and heat transfer efficiency are taken into consideration for the design in laminar or turbulent flow regions. Equations are derived which easily enable optimal design for all shapes of ducts and for all Pr numbers. It is found that optimum conditions for turbulent flow is possible for all duct hydraulic diameters; however, it is possible to have optimum conditions till a certain dimensionless duct hydraulic diameter for laminar flow. Besides maximal volumetric heat flow, heat transfer efficiency should be taken into consideration in turbulent flow for optimum design.
Breburda, C. S.; Griffin, B. P.; Pu, M.; Rodriguez, L.; Cosgrove, D. M. 3rd; Thomas, J. D.
1998-01-01
OBJECTIVES: We sought to validate direct planimetry of mitral regurgitant orifice area from three-dimensional echocardiographic reconstructions. BACKGROUND: Regurgitant orifice area (ROA) is an important measure of the severity of mitral regurgitation (MR) that up to now has been calculated from hemodynamic data rather than measured directly. We hypothesized that improved spatial resolution of the mitral valve (MV) with three-dimensional (3D) echo might allow accurate planimetry of ROA. METHODS: We reconstructed the MV using 3D echo with 3 degrees rotational acquisitions (TomTec) using a transesophageal (TEE) multiplane probe in 15 patients undergoing MV repair (age 59 +/- 11 years). One observer reconstructed the prolapsing mitral leaflet in a left atrial plane parallel to the ROA and planimetered the two-dimensional (2D) projection of the maximal ROA. A second observer, blinded to the results of the first, calculated maximal ROA using the proximal convergence method defined as maximal flow rate (2pi(r2)va, where r is the radius of a color alias contour with velocity va) divided by regurgitant peak velocity (obtained by continuous wave [CW] Doppler) and corrected as necessary for proximal flow constraint. RESULTS: Maximal ROA was 0.79 +/- 0.39 (mean +/- SD) cm2 by 3D and 0.86 +/- 0.42 cm2 by proximal convergence (p = NS). Maximal ROA by 3D echo (y) was highly correlated with the corresponding flow measurement (x) (y = 0.87x + 0.03, r = 0.95, p < 0.001) with close agreement seen (AROA (y - x) = 0.07 +/- 0.12 cm2). CONCLUSIONS: 3D echo imaging of the MV allows direct visualization and planimetry of the ROA in patients with severe MR with good agreement to flow-based proximal convergence measurements.
Virtual Classrooms: Educational Opportunity through Two-Way Interactive Television.
Hobbs, Vicki M.; Christianson, J. Scott
This book describes in non-technical language how a small school can greatly expand its course offerings by forming a two-way interactive television (I-TV) network with surrounding school districts. I-TV is the linkage of 3 to 10 school districts over fiber optic, coaxial cable, or dedicated copper telephone lines which enables participating…
Lung Disease, Indigestion, and Two-Way Tables
Watson, Jane; Callingham, Rosemary
2016-01-01
This paper considers the responses of 115 school students to two problems based on information provided in two-way tables. In each case the question asks if one of the variables involved depends on the other. Contextual knowledge might suggest a dependent relationship in both but in one problem the data show independence while in the other the…
Two-Way Regularized Fuzzy Clustering of Multiple Correspondence Analysis.
Kim, Sunmee; Choi, Ji Yeh; Hwang, Heungsun
2017-01-01
Multiple correspondence analysis (MCA) is a useful tool for investigating the interrelationships among dummy-coded categorical variables. MCA has been combined with clustering methods to examine whether there exist heterogeneous subclusters of a population, which exhibit cluster-level heterogeneity. These combined approaches aim to classify either observations only (one-way clustering of MCA) or both observations and variable categories (two-way clustering of MCA). The latter approach is favored because its solutions are easier to interpret by providing explicitly which subgroup of observations is associated with which subset of variable categories. Nonetheless, the two-way approach has been built on hard classification that assumes observations and/or variable categories to belong to only one cluster. To relax this assumption, we propose two-way fuzzy clustering of MCA. Specifically, we combine MCA with fuzzy k-means simultaneously to classify a subgroup of observations and a subset of variable categories into a common cluster, while allowing both observations and variable categories to belong partially to multiple clusters. Importantly, we adopt regularized fuzzy k-means, thereby enabling us to decide the degree of fuzziness in cluster memberships automatically. We evaluate the performance of the proposed approach through the analysis of simulated and real data, in comparison with existing two-way clustering approaches.
Transfer as a two-way process: testing a model
Vermeulen, R.; Admiraal, W.
2009-01-01
Purpose - The purpose of this exploratory research is to test the model of training transfer as a two-way process. Design/methodology/approach - Based on self-report data gathered from 58 to 44 respondents in a field experiment, it is argued that there is not just learning in the context of training
Bilingual Two-Way Immersion Programs Benefit Academic Achievement
Marian, Viorica; Shook, Anthony; Schroeder, Scott R.
2013-01-01
The effects of bilingual education on reading and math achievement were examined by comparing test scores across different elementary school programs. Results revealed that bilingual Two-Way Immersion (TWI) programs benefited both minority-language and majority-language students. Minority-language students in TWI programs outperformed their peers…
Creating Two-Way Dual Language Schools through Effective Leadership.
Aguirre-Baeza, Louisa
2001-01-01
Two-way dual language schools promote second language learning for all and develop limited-English-proficient students' primary language literacy. Effective schools demonstrate the difference between being educated in a second language and merely speaking more than one language. (SK)
无
2001-01-01
Various training methods for two way memory effect (TWME) and stressed two way memory effect (STWME) were tried on Cu-13.4Al-4.0Ni (mass fraction, %) single crystals by applying tensile stress along 〈001〉 direction of β phase. The training method of cooling with load can induce a lot of martensite prone to stabilize, thus cause large residual deformation, wide hysteresis and small TWME. Training with constant load can produce STWME larger than 8% with the least residual deformation. By training procedure of martensite reorientation below Mf followed by thermal cycling, the TWME is relatively large with very small residual deformation and with comparatively narrow hysteresis of two-way memory. The obtained two-way memory curve after such training is not a closed loop, and the obtained TWME is not stable. However, these can be improved by thermal cycling. Training with martensite reorientation below Mf and thermal cycling under relatively low constant stress throughout the whole training procedure is the optimum way of obtaining TWME, and more than 1.7% TWME can be obtained. The thermomechanical history of the sample has a pronounced effect on the training result. Thermomechanical cycling has a softening effect on martensite.
A two-way regularization method for MEG source reconstruction
Tian, Tian Siva
2012-09-01
The MEG inverse problem refers to the reconstruction of the neural activity of the brain from magnetoencephalography (MEG) measurements. We propose a two-way regularization (TWR) method to solve the MEG inverse problem under the assumptions that only a small number of locations in space are responsible for the measured signals (focality), and each source time course is smooth in time (smoothness). The focality and smoothness of the reconstructed signals are ensured respectively by imposing a sparsity-inducing penalty and a roughness penalty in the data fitting criterion. A two-stage algorithm is developed for fast computation, where a raw estimate of the source time course is obtained in the first stage and then refined in the second stage by the two-way regularization. The proposed method is shown to be effective on both synthetic and real-world examples. © Institute of Mathematical Statistics, 2012.
Two way time transfer results at NRL and USNO
Galysh, Ivan J.; Landis, G. Paul
1993-06-01
The Naval Research Laboratory (NRL) has developed a two way time transfer modem system for the United States Naval Observatory (USNO). Two modems in conjunction with a pair of Very Small Aperture Terminal (VSAT) and a communication satellite can achieve sub nanosecond time transfer. This performance is demonstrated by the results of testing at and between NRL and USNO. The modems use Code Division Multiple Access (CDMA) methods to separate their signals through a single path in the satellite. Each modem transmitted a different Pseudo Random Noise (PRN) code and received the others PRN code. High precision time transfer is possible with two way methods because of reciprocity of many of the terms of the path and hardware delay between the two modems. The hardware description was given in a previous paper.
Two way time transfer results at NRL and USNO
Galysh, Ivan J.; Landis, G. Paul
1993-01-01
The Naval Research Laboratory (NRL) has developed a two way time transfer modem system for the United States Naval Observatory (USNO). Two modems in conjunction with a pair of Very Small Aperture Terminal (VSAT) and a communication satellite can achieve sub nanosecond time transfer. This performance is demonstrated by the results of testing at and between NRL and USNO. The modems use Code Division Multiple Access (CDMA) methods to separate their signals through a single path in the satellite. Each modem transmitted a different Pseudo Random Noise (PRN) code and received the others PRN code. High precision time transfer is possible with two way methods because of reciprocity of many of the terms of the path and hardware delay between the two modems. The hardware description was given in a previous paper.
Kerner, Boris S
2016-01-01
We show that the minimization of travel times in a network as generally accepted in classical traffic and transportation theories deteriorates the traffic system through a considerable increase in the probability of traffic breakdown in the network. We introduce a network characteristic {\\it minimum network capacity} that shows that rather than the minimization of travel times in the network, the minimization of the probability of traffic breakdown in the network maximizes the network throughput at which free flow persists in the whole network.
Flexural Behavior of Two-Way Sandwiched Slabs
Pachpande, Jivan Vilas
2015-01-01
This dissertation presents the details of the findings of a study focused on evaluating the structural behavior of three-dimensional (3D) cementitious sandwich panels with Expanded Polystyrene (EPS) foam core for two-way slab applications. In this study, both theoretical and finite element numerical analysis procedures were adopted to predict the performance of such slabs under out-of-plane loading conditions. The results from theoretical and finite element analysis were verified by compariso...
Howard, Elizabeth R.; Christian, Donna
2002-01-01
In the United States, two-way immersion (TWI) is an educational approach that integrates native English speakers and native speakers of another language (usually Spanish) for content and literacy instruction in both languages. In recent years, the number of TWI programs has grown rapidly. This report examines key issues to consider when planning elementary level TWI programs, noting the fundamental characteristics that must be in place for the development of successful programs. Suggestions a...
Outage performance of two-way DF relaying systems with a new relay selection metric
Hyadi, Amal
2012-04-01
This paper investigates a new constrained relay selection scheme for two-way relaying systems where two end terminals communicate simultaneously via a relay. The introduced technique is based on the maximization of the weighted sum rate of both users. To evaluate the performance of the proposed system, the outage probability is derived in a general case (where an arbitrary channel is considered), and then over independently but not necessarily identically distributed (i.n.i.d.) Rayleigh fading channels. The analytical results are verified through simulations. © 2012 IEEE.
Improve the teaching quality by two-way education mode
Hongyan Shi
2017-02-01
Full Text Available Teaching activities contain teaching and learning, and both teachers and students have to work hard to improve the quality of teaching. This essay introduced the basic conception of “two-way and five-ring” mode first, and expatiated on the structure of this mode. The author used her own experiences to combine the teaching mode with the real situation of military school, emphasized teaching itself and talked about some spe-cific plans. This will give a certain extend help in improving the quality of teaching in military school.
Lexical need as a two-way reality cognition tool
Mark Kit
2014-09-01
Full Text Available Lexical need as a two-way reality cognition tool In this paper a concept of lexical need is introduced and its application in research of cognitive aspects of translation is discussed. Further discussion elaborates mechanisms of development of translator’s lexical space in the course of translation. Authors discuss the importance and special nature of low-frequency lexical units and difficulties encountered when studying their usage and suggest that the lexical need concept help these studies. Lexical need analysis can be also used to learn specifics of translator’s lexical space and then to take measures for selection of translators and improvement of their skills.
Two-way radios and scanners for dummies
Silver, H Ward
2013-01-01
Discover a fun new hobby with helpful possibilities Get directions, talk to folks overseas, or find out whether the fish are biting Want to check out the morning news in London, help out in emergencies, or tune in to the big race? Two-way radios open up a world of possibilities - literally. This handy guide tells you about the equipment you need, fills you in on radio etiquette, shows you how to stay legal, and gives you lots of cool ideas for family-friendly radio activities. Discover how to * Use the right radio lingo * Choose and operate different types of radios * Get a license if you n
Decoy States and Two Way Quantum Key Distribution Schemes
Shaari, J S; Ali, Sellami
2010-01-01
We study the possible application of the decoy state method on a basic two way quantum key distribution (QKD) scheme to extend its distance. Noting the obvious advantage of such a QKD scheme in allowing for single as well as double photon contributions, we derive relevant lower-bounds on the corresponding gains in a practical decoy state implementation using two intensities for decoy states. We work with two different approaches in this vein and compare these with an ideal infinite decoy state case as well as the simulation of the original LM05.
Database Security Two Way Authentication Using Graphical Password
Kamlesh Gupta
2016-04-01
Full Text Available As data represent a key asset for today's organizations. The problem is that how to protect this data from attackers, theft and misuse is at the forefront of any organization’s mind. Even though today several data security techniques are available to protect database and computing infrastructure, many such as network security and firewalls tools are unable to prevent attacks from insider. Insider is a person working in organization who can try to access the sensitive data. This paper proposes a two-way authentication method which fuses knowledge-based secret and personal trait information
The Two Way Wiretap Channel: Theory and Practice
Gamal, Aly El; Youssef, Moustafa; Gamal, Hesham El
2010-01-01
This work considers the two way wiretap channel in which two legitimate users, Alice and Bob, wish to exchange messages securely in the presence of a passive eavesdropper Eve. In the full duplex scenario, where each node can transmit and receive simultaneously, we obtain new achievable secrecy rate regions based on the idea of allowing the two users to jointly optimize their channel prefixing distributions and binning codebooks; in addition to key sharing. The new regions are shown to be strictly larger than the known ones for a wide class of discrete memoryless and Gaussian channels. In the half duplex case, where a user can only transmit or receive on any given degree of freedom, we introduce the idea of randomized scheduling and establish the significant gain it offers in terms of the achievable secrecy sum-rate. We further develop an experimental setup based on a IEEE 802.15.4-enabled sensor boards to validate our theoretical analysis. Using this testbed, it is shown that one can exploit the two way natur...
Distributed Space Time Coding for Wireless Two-way Relaying
Muralidharan, Vijayvaradharaj T
2012-01-01
We consider the wireless two-way relay channel, in which two-way data transfer takes place between the end nodes with the help of a relay. For the Denoise-And-Forward (DNF) protocol, it was shown by Koike-Akino et. al. that adaptively changing the network coding map used at the relay greatly reduces the impact of Multiple Access interference at the relay. The harmful effect of the deep channel fade conditions can be effectively mitigated by proper choice of these network coding maps at the relay. Alternatively, in this paper we propose a Distributed Space Time Coding (DSTC) scheme, which effectively removes most of the deep fade channel conditions at the transmitting nodes itself without any CSIT and without any need to adaptively change the network coding map used at the relay. It is shown that the deep fades occur when the channel fade coefficient vector falls in a finite number of vector subspaces of $\\mathbb{C}^2$, which are referred to as the singular fade subspaces. DSTC design criterion referred to as ...
Relay Selection and Resource Allocation in One-Way and Two-Way Cognitive Relay Networks
Alsharoa, Ahmad M.
2013-05-08
In this work, the problem of relay selection and resource power allocation in one- way and two-way cognitive relay networks using half duplex channels with different relaying protocols is investigated. Optimization problems for both single and multiple relay selection that maximize the sum rate of the secondary network without degrading the quality of service of the primary network by respecting a tolerated interference threshold were formulated. Single relay selection and optimal power allocation for two-way relaying cognitive radio networks using decode-and-forward and amplify-and-forward protocols were studied. Dual decomposition and subgradient methods were used to find the optimal power allocation. The transmission process to exchange two different messages between two transceivers for two-way relaying technique takes place in two time slots. In the first slot, the transceivers transmit their signals simultaneously to the relay. Then, during the second slot the relay broadcasts its signal to the terminals. Moreover, improvement of both spectral and energy efficiency can be achieved compared with the one-way relaying technique. As an extension, a multiple relay selection for both one-way and two-way relaying under cognitive radio scenario using amplify-and-forward were discussed. A strong optimization tool based on genetic and iterative algorithms was employed to solve the formulated optimization problems for both single and multiple relay selection, where discrete relay power levels were considered. Simulation results show that the practical and low-complexity heuristic approaches achieve almost the same performance of the optimal relay selection schemes either with discrete or continuous power distributions while providing a considerable saving in terms of computational complexity.
Two-way frequency trasfer on a multiplexed fiber network
Calosso, Claudio; Clivati, Cecilia; Costanzo, Giovanni A; Frittelli, Matteo; Mura, Alberto; Levi, Filippo
2013-01-01
We implemented a two-way frequency transfer technique on an optical fiber network, and demonstrate a remote comparison between optical frequencies at the 1E-21 stability level. The characterization was performed on a 47 km optical fiber that is part of the metropolitan fiber network for Internet data traffic. The technique relies on the synchronous sampling of the optical phase at the two ends of the link, that is made possible by the use of digital electronics based on an Field Programmable Gate Array (FPGA). This scheme is robust, versatile and reproducible, and can be easily upgraded to enable time transfer as well. The remote comparison of optical frequencies through optical fibers without active stabilization offers several advantages with respect to traditional Doppler cancellation schemes.
Quantum error correction assisted by two-way noisy communication.
Wang, Zhuo; Yu, Sixia; Fan, Heng; Oh, C H
2014-11-26
Pre-shared non-local entanglement dramatically simplifies and improves the performance of quantum error correction via entanglement-assisted quantum error-correcting codes (EAQECCs). However, even considering the noise in quantum communication only, the non-local sharing of a perfectly entangled pair is technically impossible unless additional resources are consumed, such as entanglement distillation, which actually compromises the efficiency of the codes. Here we propose an error-correcting protocol assisted by two-way noisy communication that is more easily realisable: all quantum communication is subjected to general noise and all entanglement is created locally without additional resources consumed. In our protocol the pre-shared noisy entangled pairs are purified simultaneously by the decoding process. For demonstration, we first present an easier implementation of the well-known EAQECC [[4, 1, 3; 1
Overlay cognitive radio systems with adaptive two-way relaying
Hyadi, Amal
2013-12-01
In this paper, we propose a spectrum sharing mechanism with a two-phase two-way relaying protocol for an overlay cognitive network. The system comprises two primary users (PUs) and two secondary users (SUs). One of the SUs acts as a relay for the PUs and gains spectrum sharing as long as he respects outage probability constraints of the primary system. Moreover, we consider that the relaying node performs an optimal power allocation scheme that minimizes the outage performance of the secondary receiver. Closed form expressions for the outage probability are derived for the cases of Decode-and-Forward (DF), Amplify-and-Forward (AF), and adaptive relaying. Numerical simulations are presented to illustrate and compare the obtained results. © 2013 IEEE.
Personality and having children: a two-way relationship.
Jokela, Markus; Kivimäki, Mika; Elovainio, Marko; Keltikangas-Järvinen, Liisa
2009-01-01
Personality has been implicated in romantic and sexual relationships, but its association with childbearing is poorly understood. The authors assessed whether 3 personality traits--sociability, emotionality, and activity--predicted the probability of having children and whether having children predicted personality change. The participants were women and men from the Cardiovascular Risk in Young Finns study (N = 1,839) who were followed for 9 years. High emotionality decreased the probability of having children, whereas high sociability and, in men, high activity increased this probability. Having children predicted increasing emotionality, particularly in participants with high baseline emotionality and two or more children. In men, having children increased sociability in those with high baseline sociability and decreased sociability in those with low baseline sociability. These findings suggest a two-way relationship between personality and having children.
The Problem of Finding the Maximal Multiple Flow in the Divisible Network and its Special Cases
A. V. Smirnov
2015-01-01
Full Text Available In the article the problem of ﬁnding the maximal multiple ﬂow in the network of any natural multiplicity k is studied. There are arcs of three types: ordinary arcs, multiple arcs and multi-arcs. Each multiple and multi-arc is a union of k linked arcs, which are adjusted with each other. The network constructing rules are described. The deﬁnitions of a divisible network and some associated subjects are stated. The important property of the divisible network is that every divisible network can be partitioned into k parts, which are adjusted on the linked arcs of each multiple and multi-arc. Each part is the ordinary transportation network. The main results of the article are the following subclasses of the problem of ﬁnding the maximal multiple ﬂow in the divisible network. 1. The divisible networks with the multi-arc constraints. Assume that only one vertex is the ending vertex for a multi-arc in k −1 network parts. In this case the problem can be solved in a polynomial time. 2. The divisible networks with the weak multi-arc constraints. Assume that only one vertex is the ending vertex for a multi-arc in s network parts (1 ≤ s < k − 1 and other parts have at least two such vertices. In that case the multiplicity of the multiple ﬂow problem can be decreased to k − s. 3. The divisible network of the parallel structure. Assume that the divisible network component, which consists of all multiple arcs, can be partitioned into subcomponents, each of them containing exactly one vertex-beginning of a multi-arc. Suppose that intersection of each pair of subcomponents is the only vertex-network source x0. If k = 2, the maximal ﬂow problem can be solved in a polynomial time. If k ≥ 3, the problem is NP-complete. The algorithms for each polynomial subclass are suggested. Also, the multiplicity decreasing algorithm for the divisible network with weak multi-arc constraints is formulated.
Maximizing the power density of aqueous electrochemical flow cells with in operando deposition
Goulet, Marc-Antoni; Ibrahim, Omar A.; Kim, Will H. J.; Kjeang, Erik
2017-01-01
To transition toward sustainable energy systems, next generation power sources must provide high power density at minimum cost. Using inexpensive and environmentally friendly fabrication methods, this work describes a room temperature electrochemical flow cell with a maximum power density of 2.01 W cm-2 or 13.4 W cm-3. In part, this is achieved by minimizing ohmic resistance through decreased electrode spacing, implementation of current collectors and improvement of electrolyte conductivity. The majority of the performance gain is provided by a novel in operando dynamic flowing deposition method for which the cell design has been optimized. Carbon nanotubes (CNTs) are deposited dynamically at the entrance of and within the carbon paper electrodes during operation of the cell. A natural equilibrium is reached between deposition and detachment of CNTs at which the electrochemical surface area and pore size distribution of the flow-through porous electrodes are greatly enhanced. In this way, the novel deposition method more than doubles the power density of the cell and sets a new performance benchmark for what is practically attainable with aqueous electrochemical flow cells. Overall, it is expected that the design and operation methods illustrated here will enable a wide range of electrochemical flow cell technologies to achieve optimal performance.
Two-Way Communication Using RFID Equipment and Techniques
Jedry, Thomas; Archer, Eric
2007-01-01
Equipment and techniques used in radio-frequency identification (RFID) would be extended, according to a proposal, to enable short-range, two-way communication between electronic products and host computers. In one example of a typical contemplated application, the purpose of the short-range radio communication would be to transfer image data from a user s digital still or video camera to the user s computer for recording and/or processing. The concept is also applicable to consumer electronic products other than digital cameras (for example, cellular telephones, portable computers, or motion sensors in alarm systems), and to a variety of industrial and scientific sensors and other devices that generate data. Until now, RFID has been used to exchange small amounts of mostly static information for identifying and tracking assets. Information pertaining to an asset (typically, an object in inventory to be tracked) is contained in miniature electronic circuitry in an RFID tag attached to the object. Conventional RFID equipment and techniques enable a host computer to read data from and, in some cases, to write data to, RFID tags, but they do not enable such additional functions as sending commands to, or retrieving possibly large quantities of dynamic data from, RFID-tagged devices. The proposal would enable such additional functions. The figure schematically depicts an implementation of the proposal for a sensory device (e.g., a digital camera) that includes circuitry that converts sensory information to digital data. In addition to the basic sensory device, there would be a controller and a memory that would store the sensor data and/or data from the controller. The device would also be equipped with a conventional RFID chipset and antenna, which would communicate with a host computer via an RFID reader. The controller would function partly as a communication interface, implementing two-way communication protocols at all levels (including RFID if needed) between the
Periodontitis and diabetes: a two-way relationship.
Preshaw, P M; Alba, A L; Herrera, D; Jepsen, S; Konstantinidis, A; Makrilakis, K; Taylor, R
2012-01-01
Periodontitis is a common chronic inflammatory disease characterised by destruction of the supporting structures of the teeth (the periodontal ligament and alveolar bone). It is highly prevalent (severe periodontitis affects 10-15% of adults) and has multiple negative impacts on quality of life. Epidemiological data confirm that diabetes is a major risk factor for periodontitis; susceptibility to periodontitis is increased by approximately threefold in people with diabetes. There is a clear relationship between degree of hyperglycaemia and severity of periodontitis. The mechanisms that underpin the links between these two conditions are not completely understood, but involve aspects of immune functioning, neutrophil activity, and cytokine biology. There is emerging evidence to support the existence of a two-way relationship between diabetes and periodontitis, with diabetes increasing the risk for periodontitis, and periodontal inflammation negatively affecting glycaemic control. Incidences of macroalbuminuria and end-stage renal disease are increased twofold and threefold, respectively, in diabetic individuals who also have severe periodontitis compared to diabetic individuals without severe periodontitis. Furthermore, the risk of cardiorenal mortality (ischaemic heart disease and diabetic nephropathy combined) is three times higher in diabetic people with severe periodontitis than in diabetic people without severe periodontitis. Treatment of periodontitis is associated with HbA(1c) reductions of approximately 0.4%. Oral and periodontal health should be promoted as integral components of diabetes management.
Diabetes and hepatitis C : A two-way association
Sara Salehi Hammerstad
2015-09-01
Full Text Available Diabetes and hepatitis C infection are both prevalent diseases worldwide, and are associated with increased morbidity and mortality. Most studies, but not all, have shown that patients with chronic hepatitis C are more prone to develop type 2 diabetes compared to healthy controls, as well as when compared to patients with other liver diseases including hepatitis B. Furthermore, epidemiological studies have revealed that patients with type 2 diabetes may also be at higher risk for worse outcomes of their hepatitis C infection, including reduced rate of sustained virologic response, progression to fibrosis and cirrhosis, and higher risk for development of hepatocellular carcinoma. Moreover, hepatitis C infection and mainly its treatment, interferon α, can trigger the development of type 1 diabetes. In this review we discuss the existing data on this two-way association between diabetes and hepatitis C infection with emphasis on possible mechanisms. It remains to be determined whether the new curative therapies for chronic hepatitis C will improve outcomes in diabetic hepatitis C patients, and conversely whether treatment with Metformin will reduce complications from HCV infection. We propose an algorithm for diabetes screening and follow-up in hepatitis C patients.
Coupled Two-Way Clustering Analysis of Gene Microarray Data
Getz, G; Domany, E
2000-01-01
We present a novel coupled two-way clustering approach to gene microarray data analysis. The main idea is to identify subsets of the genes and samples, such that when one of these is used to cluster the other, stable and significant partitions emerge. The search for such subsets is a computationally complex task: we present an algorithm, based on iterative clustering, which performs such a search. This analysis is especially suitable for gene microarray data, where the contributions of a variety of biological mechanisms to the gene expression levels are entangled in a large body of experimental data. The method was applied to two gene microarray data sets, on colon cancer and leukemia. By identifying relevant subsets of the data and focusing on them we were able to discover partitions and correlations that were masked and hidden when the full dataset was used in the analysis. Some of these partitions have clear biological interpretation; others can serve to identify possible directions for future research.
Two-way conversations between cold atoms and semiconductors
Judd, Thomas [University of Tuebingen (Germany); University of Nottingham (United Kingdom); Scott, Robin; Sinuco, German; Montgomery, Tom; Krueger, Peter; Fromhold, Mark [University of Nottingham (United Kingdom); Martin, Andrew [University of Melbourne (Australia)
2010-07-01
There has been significant work in the past few years on hybrid devices which combine cold atoms with solid state structures. The hope is to create devices which combine the key advantages of both systems - the purity of a quantum coherent atom cloud, and the versatility of microchips - to study fundamental physics and further quantum technologies. To date there has been much success in manipulating cold atoms with microchips and semiconductors to create a measurable signal in the atom cloud. However, it has not been possible to perform the reverse procedure of using cold atoms to create a measurable signal in a solid state device. If this two-way coupling can be achieved, a range of possibilities open up such as long-term quantum memory chips. Here we use simulations to show that Fresnel zone plates could assist these efforts by strongly and coherently focusing ultracold atoms onto a semiconductor chip with a two-dimensional electron gas (2DEG). The atoms are shown to deplete the 2DEG, thereby strongly increasing its resistivity to measurable levels. The technique provides a solution to the long standing problem of short-range atom focusing while at the same time opening the door to a new form of non-destructive lithography which can create electronic components on a 50nm scale.
Periodontitis and type II diabetes: a two-way relationship.
Chee, Brian; Park, Boram; Bartold, P Mark
2013-12-01
For many years an association between diabetes and periodontitis has been suspected. In more recent times this relationship has been suggested to be bidirectional with each condition being able to influence the other. In this review the two-way relationship between diabetes and periodontitis is considered. For this narrative review a very broad search strategy of the literature was developed using both EMBASE and MEDLINE (via PubMed) databases. The reference lists from the selected papers were also scanned, and this provided an additional source of papers for inclusion and further assessment. The data available suggest that diabetes is a risk as well as a modifying factor for periodontitis. Individuals with diabetes are more likely to have periodontitis and with increased severity when diabetes is uncontrolled/poorly controlled. Possible mechanisms of how diabetes affects periodontitis include adipokine-mediated inflammation, neutrophil dysfunction, uncoupling of bone and advanced glycation end-products-receptor for advanced glycation end-products interaction. Evidence is accruing to support how periodontitis can affect diabetes and complications associated with diabetes. There is some evidence demonstrating that periodontal therapy can result in a moderate improvement in glycaemic control. Available evidence indicates that diabetes and peridontitis are intricately interrelated and that each condition has the capacity to influence clinical features of each other.
Coupled two-way clustering analysis of gene microarray data
Getz, Gad; Levine, Erel; Domany, Eytan
2000-10-01
We present a coupled two-way clustering approach to gene microarray data analysis. The main idea is to identify subsets of the genes and samples, such that when one of these is used to cluster the other, stable and significant partitions emerge. The search for such subsets is a computationally complex task. We present an algorithm, based on iterative clustering, that performs such a search. This analysis is especially suitable for gene microarray data, where the contributions of a variety of biological mechanisms to the gene expression levels are entangled in a large body of experimental data. The method was applied to two gene microarray data sets, on colon cancer and leukemia. By identifying relevant subsets of the data and focusing on them we were able to discover partitions and correlations that were masked and hidden when the full dataset was used in the analysis. Some of these partitions have clear biological interpretation; others can serve to identify possible directions for future research.
Ryo Hase
2016-01-01
Full Text Available This paper presents a sequential solution method to discover efficient trades in an electricity market model. The market model represents deregulated electricity market consisting of four types of participants: independent power producers, retailers, public utilities, and consumers. Our model is based on graph theory, and the market participants are denoted by a network composes of three types of agents including sellers, buyers, and traders. The market participants have different capacity and demand of electricity from each other, and each electricity trade should satisfy the capacity and demand. Our sequential solution method can discover efficient electricity trades satisfying the constraints regarding capacity and demand by utilizing network flow. Simulation results demonstrate the efficiency of electricity trades determined by our method by examining social welfare, which is the total of payoffs of all market participants. Furthermore, the simulation results also indicate the allocation of payoff to each market participant.
Luis Fialho
2016-06-01
Full Text Available This paper presents the results of the implementation of a self-consumption maximization strategy tested in a real-scale Vanadium Redox Flow Battery (VRFB (5 kW, 60 kWh and Building Integrated Photovoltaics (BIPV demonstrator (6.74 kWp. The tested energy management strategy aims to maximize the consumption of energy generated by a BIPV system through the usage of a battery. Whenever possible, the residual load is either stored in the battery to be used later or is supplied by the energy stored previously. The strategy was tested over seven days in a real-scale VRF battery to assess the validity of this battery to implement BIPV-focused energy management strategies. The results show that it was possible to obtain a self-consumption ratio of 100.0%, and that 75.6% of the energy consumed was provided by PV power. The VRFB was able to perform the strategy, although it was noticed that the available power (either to charge or discharge varied with the state of charge.
Bandwidth and power allocation for two-way relaying in overlay cognitive radio systems
Alsharoa, Ahmad M.
2014-12-01
In this paper, the problem of both bandwidth and power allocation for two-way multiple relay systems in overlay cognitive radio (CR) setup is investigated. In the CR overlay mode, primary users (PUs) cooperate with cognitive users (CUs) for mutual benefits. In our framework, we propose that the CUs are allowed to allocate a part of the PUs spectrum to perform their cognitive transmission. In return, acting as an amplify-and-forward two-way relays, they are used to support PUs to achieve their target data rates over the remaining bandwidth. More specifically, CUs acts as relays for the PUs and gain some spectrum as long as they respect a specific power budget and primary quality-of-service constraints. In this context, we first derive closed-form expressions for optimal transmit power allocated to PUs and CUs in order to maximize the cognitive objective. Then, we employ a strong optimization tool based on particle swarm optimization algorithm to find the optimal relay amplification gains and optimal cognitive released bandwidths as well. Our numerical results illustrate the performance of our proposed algorithm for different utility metrics and analyze the impact of some system parameters on the achieved performance.
A genetic algorithm for multiple relay selection in two-way relaying cognitive radio networks
Alsharoa, Ahmad M.
2013-09-01
In this paper, we investigate a multiple relay selection scheme for two-way relaying cognitive radio networks where primary users and secondary users operate on the same frequency band. More specifically, cooperative relays using Amplifyand- Forward (AF) protocol are optimally selected to maximize the sum rate of the secondary users without degrading the Quality of Service (QoS) of the primary users by respecting a tolerated interference threshold. A strong optimization tool based on genetic algorithm is employed to solve our formulated optimization problem where discrete relay power levels are considered. Our simulation results show that the practical heuristic approach achieves almost the same performance of the optimal multiple relay selection scheme either with discrete or continuous power distributions. Copyright © 2013 by the Institute of Electrical and Electronic Engineers, Inc.
Precoder Design and Power Allocation for MIMO Cognitive Radio Two-Way Relaying Systems
Sboui, Lokman
2016-08-11
In this paper, we study a multiple-antenna two-way relaying (TWR) cognitive radio (CR) system. A space alignment (SA) technique is adopted by the secondary users (SUs) to avoid interference with the primary users (PUs). We derive the optimal power allocation that maximizes the TWR achievable SU sum- rate while respecting the total power budget and the relay power constraints. We also analyze the case in which the relay is able to optimize its gain matrix structure to enhance the SU sum-rate. In the numerical results, we quantify the sum-rate gain of using the SA in the TWR CR and we show that the SU sum-rate is very limited when the relay power is low or the PU power and its resulting interference are high. In addition, we optimize the relay gain using an iterative algorithm and compare between different relay matrix structures.
A low complexity algorithm for multiple relay selection in two-way relaying Cognitive Radio networks
Alsharoa, Ahmad M.
2013-06-01
In this paper, a multiple relay selection scheme for two-way relaying cognitive radio network is investigated. We consider a cooperative Cognitive Radio (CR) system with spectrum sharing scenario using Amplify-and-Forward (AF) protocol, where licensed users and unlicensed users operate on the same frequency band. The main objective is to maximize the sum rate of the unlicensed users allowed to share the spectrum with the licensed users by respecting a tolerated interference threshold. A practical low complexity heuristic approach is proposed to solve our formulated optimization problem. Selected numerical results show that the proposed algorithm reaches a performance close to the performance of the optimal multiple relay selection scheme either with discrete or continuous power distributions while providing a considerable saving in terms of computational complexity. In addition, these results show that our proposed scheme significantly outperforms the single relay selection scheme. © 2013 IEEE.
Energy Efficiency and Goodput Analysis in Two-Way Wireless Relay Networks
Chen, Qing
2011-01-01
In this paper, we study two-way relay networks (TWRNs) in which two source nodes exchange their information via a relay node indirectly in Rayleigh fading channels. Both Amplify-and-Forward (AF) and Decode-and-Forward (DF) techniques have been analyzed in the TWRN employing a Markov chain model through which the network operation is described and investigated in depth. Automatic Repeat-reQuest (ARQ) retransmission has been applied to guarantee the successful packet delivery. The bit energy consumption and goodput expressions have been derived as functions of transmission rate in a given AF or DF TWRN. Numerical results are used to identify the optimal transmission rates where the bit energy consumption is minimized or the goodput is maximized. The network performances are compared in terms of energy and transmission efficiency in AF and DF modes.
On achievable rate of two-way relaying cognitive radio with space alignment
Sboui, Lokman
2015-09-11
We study a multiple-antenna two-way relaying (TWR) spectrum sharing system. A space alignment (SA) technique is adopted by the secondary users (SU\\'s) to avoid interference with the primary users (PU\\'s). We derive the optimal power allocation that maximizes the TWR achievable sum-rate of the SU while respecting the total power budget and the relay power constraints. In the numerical results, we quantify the sum-rate gain of using the SA in the TWR CR and we show that the SU sum-rate is very limited when the relay power is low or the PU\\'s power and its resulting interference is high. © 2015 IEEE.
Symmetry breaking in optimal timing of traffic signals on an idealized two-way street
Panaggio, Mark J.; Ottino-Löffler, Bertand J.; Hu, Peiguang; Abrams, Daniel M.
2013-09-01
Simple physical models based on fluid mechanics have long been used to understand the flow of vehicular traffic on freeways; analytically tractable models of flow on an urban grid, however, have not been as extensively explored. In an ideal world, traffic signals would be timed such that consecutive lights turned green just as vehicles arrived, eliminating the need to stop at each block. Unfortunately, this “green-wave” scenario is generally unworkable due to frustration imposed by competing demands of traffic moving in different directions. Until now this has typically been resolved by numerical simulation and optimization. Here, we develop a theory for the flow in an idealized system consisting of a long two-way road with periodic intersections. We show that optimal signal timing can be understood analytically and that there are counterintuitive asymmetric solutions to this signal coordination problem. We further explore how these theoretical solutions degrade as traffic conditions vary and automotive density increases.
Symmetry breaking in optimal timing of traffic signals on an idealized two-way street
Panaggio, Mark J; Hu, Peiguang; Abrams, Daniel M
2013-01-01
Simple physical models based on fluid mechanics have long been used to understand the flow of vehicular traffic on freeways; analytically tractable models of flow on an urban grid, however, have not been as extensively explored. In an ideal world, traffic signals would be timed such that consecutive lights turned green just as vehicles arrived, eliminating the need to stop at each block. Unfortunately, this "green wave" scenario is generally unworkable due to frustration imposed by competing demands of traffic moving in different directions. Until now this has typically been resolved by numerical simulation and optimization. Here, we develop a theory for the flow in an idealized system consisting of a long two-way road with periodic intersections. We show that optimal signal timing can be understood analytically and that there are counter-intuitive asymmetric solutions to this signal coordination problem. We further explore how these theoretical solutions degrade as traffic conditions vary and automotive dens...
Margareta RACOVITA
2011-11-01
Full Text Available This work proposes to solve a problem related to maximizing hotels’ revenues through two methods established in operational research domain. In the first part of the paper, the approach involves formulating the objective function and problem’s constraints, as well as the expansion of the model, taking into consideration clients’ preferences and the opportunities of group reservations. In the second part of the paper, the problem is solved with the help of network flows model, which allows optimum allocation of the rooms in real time. At the end of the paper, there are highlighted the advantages of applying those two mathematic methods within the strategies of performances development within hotel industry.
Osmotically driven flows and maximal transport rates in systems of long, linear porous pipes
Rademaker, Hanna; Bohr, Tomas
2016-01-01
We study the flow of water and solutes in linear cylindrical pipes with semipermeable walls (membranes), driven by concentration differences across the membranes, inspired by the sieve tubes in conifer needles. The aim is to determine the efficiency of such systems. For single pipes, we assume that the velocity at the entrance (the tip of the needle) is zero, and we determine the velocity profile throughout the pipe and the outflow at the end of the pipe, where the pressure is specified. This is done for the particular case where the concentration of the solute is constant inside the pipe, and it is shown that the system has a characteristic length scale $L_{\\text{eff}}$ depending on the pipe radius, the permeability of the wall and the viscosity of the fluid such that pipes with lengths $L \\gg L_{\\text{eff}}$ will contain a stagnant zone from the entrance, where the velocity is very small. The outflow comes from a region of length $L_{\\text{eff}}$ near the end, and the increase of velocity, if the pipe is ma...
Optimization of a two-way MIMO amplify-and-forward relay network
Zhang, Ying; Chen, Yinjiang; Pan, Chuanyi; Zhao, Huapeng; Kang, Ning
2014-12-01
In this paper, we consider optimization of a two-way multiple-input multiple-output (MIMO) amplify-and-forward relay network which consists of a pair of transceivers and several relay nodes. Multiple antennas are equipped on the transceivers and relays. Multiple access broadcast scheme which finishes communication in two time slots is considered. In the first time slot, signals received by the relays are scaled by several beamforming matrices. In the second time slot, the relays transmit the scaled signals to the two transceivers. Upon receiving these signals, a MIMO equalizer is implemented at each transceiver to recover the desired signal. In this paper, zero forcing equalizers are used. Joint optimization of the beamforming matrices and the equalizers are realized using the following criteria: 1) the total relay transmission power is minimized subject to the minimal output signal-to-noise ratio (SNR) constraint at each transceiver, 2) the minimal output SNR of the two transceivers is maximized subject to total relay transmission power constraint, and 3) the minimal output SNR of the two transceivers is maximized subject to individual relay transmission power constraint. It is shown that the proposed optimization problems can be formulated as the second-order cone programming problems which can be solved efficiently. The validity of the proposed algorithm is verified by computer simulations.
Double criticality and the two-way Boussinesq equation in stratified shallow water hydrodynamics
Bridges, Thomas J.; Ratliff, Daniel J.
2016-06-01
Double criticality and its nonlinear implications are considered for stratified N-layer shallow water flows with N = 1, 2, 3. Double criticality arises when the linearization of the steady problem about a uniform flow has a double zero eigenvalue. We find that there are two types of double criticality: non-semisimple (one eigenvector and one generalized eigenvector) and semi-simple (two independent eigenvectors). Using a multiple scales argument, dictated by the type of singularity, it is shown that the weakly nonlinear problem near double criticality is governed by a two-way Boussinesq equation (non-semisimple case) and a coupled Korteweg-de Vries equation (semisimple case). Parameter values and reduced equations are constructed for the examples of two-layer and three-layer stratified shallow water hydrodynamics.
Meguro,Tadamichi
1991-02-01
Full Text Available Pulmonary function tests were performed on 252 healthy young subjects free from respiratory and allergic symptoms, and 80 young subjects with past history of nasal allergy (PNA and 10 subjects with past history of bronchial asthma (PBA. All the subjects were non-smokers. Maximal expiratory flow-volume (MEFV curves were visually classified into five types (A-E. The percent distribution of type A in healthy subjects was significantly higher than in the PNA group, while the total sum of percentage of types B, C, and D in the PNA group was significantly higher than in the healthy subjects. The percent distribution of type E in the PNA group was similar to that in the healthy subjects. The percent distribution of MEFV types were significantly different between healthy males and healthy females. The percent distribution of types A, B and E were the highest in healthy subjects, PNA and PBA groups, respectively. Conclusively, the difference in the percent distributions of MEFV types was recognized among healthy subjects, PNA and PBA groups.
Two-way Fluid-Structure Interaction Simulation of a Micro Horizontal Axis Wind Turbine
Yi-Bao Chen
2015-01-01
Full Text Available A two-way Fluid-Structure Interaction (FSI analyses performed on a micro horizontal axis wind turbine (HAWT which coupled the CFX solver with Structural solver in ANSYS Workbench was conducted in this paper. The partitioned approach-based non-conforming mesh methods and the k-ε turbulence model were adopted to perform the study. Both the results of one-way and two-way FSI analyses were presented and compared with each other, and discrepancy of the results, especially the mechanical properties, were analysed. Grid convergence which is crucial to the results was performed, and the relationship between the inner flow field domain (rotational domain and the number of grids (number of cells, elements was verified for the first time. Dynamical analyses of the wind turbine were conducted using the torque as a reference value, to verify the rationality of the model which dominates the accuracy of results. The optimal case was verified and used to conduct the study, thus, the results derived from the simulation of the FSI are accurate and credible.
Lifetime maximization routing with network coding in wireless multihop networks
DING LiangHui; WU Ping; WANG Hao; PAN ZhiWen; YOU XiaoHu
2013-01-01
In this paper, we consider the lifetime maximization routing with network coding in wireless mul- tihop networks. We first show that lifetime maximization with network coding is different from pure routing, throughput maximization with network coding and energy minimization with network coding. Then we formulate lifetime maximization problems in three different cases of （i） no network coding, （ii） two-way network coding, and （iii） overhearing network coding. To solve these problems, we use flow augmenting routing （FA） for the first case, and then extend the FA with network coding （FANC） by using energy minimized one-hop network coding. After that, we investigate the influence of parameters of FANC, evaluate the performance of FANC with two-way and overhearing network coding schemes and compare it with that without network coding under two different power control models, namely, protocol and physical ones. The results show that the lifetime can be improved significantly by using network coding, and the performance gain of network coding decreases with the increase of flow asymmetry and the power control ability.
Alsharoa, Ahmad M.
2014-06-01
In this paper, the problem of power allocation for a multiple-input multiple-output two-way system is investigated in underlay Cognitive Radio (CR) set-up. In the CR underlay mode, secondary users are allowed to exploit the spectrum allocated to primary users in an opportunistic manner by respecting a tolerated temperature limit. The secondary networks employ an amplify-and-forward two-way relaying technique in order to maximize the sum rate under power budget and interference constraints. In this context, we formulate an optimization problem that is solved in two steps. First, we derive a closed-form expression of the optimal power allocated to terminals. Then, we employ a strong optimization tool based on particle swarm optimization algorithm to find the power allocated to secondary relays. Simulation results demonstrate the efficiency of the proposed solution and analyze the impact of some system parameters on the achieved performance. © 2014 IEEE.
2013-05-24
... Proceeding; Certain Two-Way Global Satellite Communication Devices, System and Components Thereof; Notice of... United States after importation of certain two-way global satellite communication devices, system and... States after importation any two-way global satellite communication devices, system, and components...
Two-way Shape Memory Effect of NiTi under Compressive Loading Cycles
Yoo, Young Ik; Lee, Jung Ju
In this study, the two-way shape memory effect (TWSME) of a Ni-54.5 at.% Ti alloy was investigated experimentally to develop a NiTi linear actuator. The two-way shape memory effect was induced through a compressive shape memory cycle composed of four steps: (1) loading to maximum deformation; (2) unloading; (3) heating; (4) and cooling. Six types of specimens (one solid cylindrical and five tubular) were used to obtain the twoway shape memory strain and two-way recovery stress and to evaluate the actuating capacity. The two-way actuating strain showed a convergent tendency after several training cycles for the same maximum deformation. A maximum value of the two-way strain was obtained for 7% of maximum deformation, independently of the geometry of the tubular specimens. The two-way strains obtained by the shape memory cycles and two-way recovery stress linearly increase as a function of the maximum deformation and the two-way strain, respectively, and the geometry of specimen affects the two-way recovery stress. Although the results show that sufficient recovery stress can be generated by either the two-way shape memory process or by the one-way shape memory process, the two-way shape memory process can be applied more conveniently to actuating applications.
Cross-Layer Design for Two-Way Relaying Networks with Multiple Antennas
zhuo wu
2015-10-01
Full Text Available In this paper, we developed a cross-layer design for two-way relaying (TWR networks with multiple antennas, where two single antenna source nodes exchange information with the aid of one multiple antenna relay node. The proposed cross-layer design considers adaptive modulation (AM and space-time block coding (STBC at the physical layer with an automatic repeat request (ARQ protocol at the data link layer, in order to maximize the spectral efficiency under specific delay and packet error ratio (PER constraints. An MMSE-interference cancellation (IC receiver is employed at the relay node, to remove the interference in the fist phase of the TWR transmission. The transmission mode is updated for each phase of the TWR transmission on a frame-by-frame basis, to match the time-varying channel conditions and exploit the system performance and throughput gain. Simulation results show that retransmission at the data link layer could alleviate rigorous error-control requirements at the physical layer, and thereby allows higher data transmission. As a result, cross-layer design helps to achieve considerable system spectral efficiency gain for TWR networks, compared to those without cross-layer design.
Cognitive two-way relay beamforming: Design with resilience to channel state uncertainties
Ubaidulla, P.
2016-07-26
In this paper, we propose a robust distributed relay beamformer design for cognitive radio network operating under uncertainties in the available channel state information. The cognitive network consists of a pair of transceivers and a set of non-regenerative two-way relays that assist the communication between the transceiver pair. The secondary nodes share the spectrum with a licensed primary user node while ensuring that the interference to the primary receiver is maintained below a certain threshold. The proposed robust design maximizes the worst-case signal-to-interference-plus-noise ratio at the secondary transceivers while satisfying constraints on the interference to the primary user and on the total relay transmit power. Though the robust design problem is not a convex problem in its original form, we show that it can be reformulated as a convex optimization problem, which can be solved efficiently. Numerical results are provided and illustrate the merits of the proposed design for various operating conditions and parameters. © 2016 IEEE.
Kerner, Boris S.
2016-09-01
We have revealed general physical conditions for the maximization of the network throughput at which free flow conditions are ensured, i.e., traffic breakdown cannot occur in the whole traffic or transportation network. A physical measure of the network - network capacity is introduced that characterizes general features of the network with respect to the maximization of the network throughput. The network capacity allows us also to make a general proof of the deterioration of traffic system occurring when dynamic traffic assignment is performed in a network based on the classical Wardrop' user equilibrium (UE) and system optimum (SO) equilibrium.
Nikolopoulos, G M; Ranade, K S; Alber, Gernot; Nikolopoulos, Georgios M.; Ranade, Kedar S.
2006-01-01
We investigate the error tolerance of quantum cryptographic protocols using $d$-level systems. In particular, we focus on prepare-and-measure schemes that use two mutually unbiased bases and a key-distillation procedure with two-way classical communication. For arbitrary quantum channels, we obtain a sufficient condition for secret-key distillation which, in the case of isotropic quantum channels, yields an analytic expression for the maximally tolerable error rate of the cryptographic protocols under consideration. The difference between the tolerable error rate and its theoretical upper bound tends slowly to zero for sufficiently large dimensions of the information carriers.
Syed-shah KHALID; Liang ZHANG; Xue-wei ZHANG; Ke SUN
2013-01-01
The objective of this study was to develop,as well as validate the strongly coupled method(two-way fluid structural interaction(FSI))used to simulate the transient FSI response of the vertical axis tidal turbine (VATT)rotor,subjected to spatially varying inflow.Moreover,this study examined strategies on improving techniques used for mesh deformation that account for large displacement or deformation calculations.The blade's deformation for each new time step is considered in transient two-way FSI analysis,to make the design more reliable.Usually this is not considered in routine one-way FSI simulations.A rotor with four blades and 4-m diameter was modeled and numerically analyzed.We observed that two-way FSI,utilizing the strongly coupled method,was impossible for a complex model;and thereby using ANSYS-CFX and ANSYS-MECHANICAL in work bench,as given in ANSYS-WORKBENCH,helped case examples 22 and 23,by giving an error when the solution was run.To make the method possible and reduce the computational power,a novel technique was used to transfer the file in ANSYS-APDL to obtain the solution and results.Consequently,the results indicating a two-way transient FSI analysis is a time-and resource-consuming job,but with our proposed technique we can reduce the computational time.The ANSYS STRUCTURAL results also uncover that stresses and deformations have higher values for two-way FSI as compared to one-way FSI.Similarly,fluid flow CFX results for two-way FSI are closer to experimental results as compared to one-way simulation results.Additionally,this study shows that,using the proposed method we can perform coupled simulation with simple multi-node PCs(core i5).
Robustness of two-way quantum communication protocols against Trojan horse attack
Deng, F G; Li, X H; Zhou, H Y; Zhou, P
2005-01-01
We discuss the robustness of two-way quantum communication protocols against Trojan horse attack and introduce a novel attack, delay-photon Trojan horse attack. Moreover, we present a practical way for two-way quantum communication protocols to prevent the eavesdropper from stealing the information transmitted with Trojan horse attacks. It means that two-way quantum communication protocols is also secure in a practical application.
A comparison of one-way video and two-way video educational videoteleconferencing
Hendrix, Craig L.
1995-05-01
The literature reviewed in this study supported the effectiveness of educational videoteleconferencing; however, relatively little research was found comparing the two most interactive types of educational videoteleconferencing systems. An experimental research project was conducted, attempting to determine which educational videoteleconferencing system is more effective. Specifically, this project was designed to answer the following question: Is live two-way video with two-way audio more effective than live one-way video with two-way audio educational videoteleconferencing (EVC)?
Sheri K Palejwala
2014-01-01
Full Text Available Background: The requirement for frequent intraventricular drug delivery in the setting of shunt dependence is particularly challenging in the treatment of central nervous system infection, neoplastic disease, and hemorrhage. This is especially relevant in the pediatric population where both hematogenous malignancy requiring intrathecal drug delivery and shunt-dependent hydrocephalus are more prevalent. Intrathecal and intraventricular chemotherapy agents can be prematurely diverted in these shunt-dependent patients. Case Description: We report the use of a stop-flow programmable shunt valve to maximize delivery of intraventricular chemotherapy in a child with acute lymphoblastic leukemia and disseminated intravascular coagulation who presented with spontaneous intracerebral and intraventricular hemorrhages. The patient then developed posthemorrhagic hydrocephalus and eventually progressed to shunt dependence but still required frequent intraventricular chemotherapy administration. A ventriculoperitoneal shunt, equipped with a valve that allows for near cessation of cerebrospinal fluid flow (Certas; , Codman, Raynham, MA, and a contralateral Ommaya reservoir were inserted to maximize intraventricular dissemination of chemotherapy. Conclusions: To the best of our knowledge, this is the first reported case of the use of a high-resistance programmable valve being used to virtually cease cerebrospinal fluid flow through the distal catheter temporarily in order to maximize intraventricular drug dissemination in a pediatric patient with acute lymphoblastic leukemia.
Krishna, Hemanth; Kumar, Hemantha; Gangadharan, Kalluvalappil
2016-06-01
A magneto rheological (MR) fluid damper offers cost effective solution for semiactive vibration control in an automobile suspension. The performance of MR damper is significantly depends on the electromagnetic circuit incorporated into it. The force developed by MR fluid damper is highly influenced by the magnetic flux density induced in the fluid flow gap. In the present work, optimization of electromagnetic circuit of an MR damper is discussed in order to maximize the magnetic flux density. The optimization procedure was proposed by genetic algorithm and design of experiments techniques. The result shows that the fluid flow gap size less than 1.12 mm cause significant increase of magnetic flux density.
Krishna, Hemanth; Kumar, Hemantha; Gangadharan, Kalluvalappil
2017-08-01
A magneto rheological (MR) fluid damper offers cost effective solution for semiactive vibration control in an automobile suspension. The performance of MR damper is significantly depends on the electromagnetic circuit incorporated into it. The force developed by MR fluid damper is highly influenced by the magnetic flux density induced in the fluid flow gap. In the present work, optimization of electromagnetic circuit of an MR damper is discussed in order to maximize the magnetic flux density. The optimization procedure was proposed by genetic algorithm and design of experiments techniques. The result shows that the fluid flow gap size less than 1.12 mm cause significant increase of magnetic flux density.
Brendle, Joerg
2016-01-01
We show that, consistently, there can be maximal subtrees of P (omega) and P (omega) / fin of arbitrary regular uncountable size below the size of the continuum. We also show that there are no maximal subtrees of P (omega) / fin with countable levels. Our results answer several questions of Campero, Cancino, Hrusak, and Miranda.
33 CFR 167.173 - Off Delaware Bay: Two-Way Traffic Route.
2010-07-01
... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Off Delaware Bay: Two-Way Traffic... SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY OFFSHORE TRAFFIC SEPARATION SCHEMES Description of Traffic Separation Schemes and Precautionary Areas Atlantic East Coast § 167.173 Off Delaware Bay: Two-Way Traffic...
An Experimental Two-Way Video Teletraining System: Design, Development and Evaluation.
Simpson, Henry; And Others
1991-01-01
Describes the design, development, and evaluation of an experimental two-way video teletraining (VTT) system by the Navy that consisted of two classrooms linked by a land line to enable two-way audio/video communication. Trends in communication and computer technology for training are described, and a cost analysis is included. (12 references)…
2012-09-21
... COMMISSION Certain Two-Way Global Satellite Communication Devices, System and Components Thereof; Institution...-way global satellite communication devices, system and components thereof by reason of infringement of... after importation of certain two-way global satellite communication devices, system and components...
An Experimental Two-Way Video Teletraining System: Design, Development and Evaluation.
Simpson, Henry; And Others
1991-01-01
Describes the design, development, and evaluation of an experimental two-way video teletraining (VTT) system by the Navy that consisted of two classrooms linked by a land line to enable two-way audio/video communication. Trends in communication and computer technology for training are described, and a cost analysis is included. (12 references)…
Two-Way Text Messaging: An Interactive Mobile Learning Environment in Higher Education
Premadasa, H. K. Salinda; Meegama, R. G. N.
2016-01-01
Short messaging service (SMS) is perhaps the most popular mobile technology prevalent among students in higher education due to its ubiquitous nature and the capability of two-way communication. However, a major limitation in two-way text messaging is sending back a part of received data with the reply message. This limitation results in users of…
Chen, Jing; Lin, Lan; Jiang, Rui
2017-01-01
In this paper, we study the capacity of a highway with two on-ramps and one off-ramp in between by using a cellular automaton traffic flow model. We investigate how to maximize the system capacity by assigning proper traffic flow to the two on-ramps. The system phase diagram is presented and eight different regions are observed under different conditions. It is shown that in region I, in which both on-ramps are in free flow and the main road upstream of the upstream on-ramp is in congestion, assigning proper proportion of the demand to two on-ramps could maximize the system capacity. Two critical values of the off-ramp flow ratio poff have been observed. When poff p off , c 2, no demand should be assigned to the upstream on-ramp. An analytical investigation has been performed to calculate the critical values. The analytical results are in good agreement with the simulation ones.
Suresh Chintalapudi Venkata
2015-09-01
Full Text Available In this paper a novel non-linear optimization problem is formulated to maximize the social welfare in restructured environment with generalized unified power flow controller (GUPFC. This paper presents a methodology to optimally allocate the reactive power by minimizing voltage deviation at load buses and total transmission power losses so as to maximize the social welfare. The conventional active power generation cost function is modified by combining costs of reactive power generated by the generators, shunt capacitors and total power losses to it. The formulated objectives are optimized individually and simultaneously as multi-objective optimization problem, while satisfying equality, in-equality, practical and device operational constraints. A new optimization method, based on two stage initialization and random distribution processes is proposed to test the effectiveness of the proposed approach on IEEE-30 bus system, and the detailed analysis is carried out.
The two-way feedback and passing-way of human body
Zhang Liang; Zhang Kui; Zhang Renxiang
2008-01-01
Two-way feedback of human body was published in 1992. The sensation of two-way feedback of body is a spe-cial system of human reaction, which maintains and regulates symmetry and balance of human body. The human two-way feedback reacts to human health. For human overall health and delay decrepitude, it is necessary to pay attention to the stimulations (passive acceptance and initiative interventions) and relevant influences in human body and the stimu-lative effect. In this paper, the experimental research of stimulation and an example of two-way feedback in human body are given. And lay a foundation of prevention, medical treatment and hygiene of human overall health.
A model of two-way selection system for human behavior.
Bin Zhou
Full Text Available Two-way selection is a common phenomenon in nature and society. It appears in the processes like choosing a mate between men and women, making contracts between job hunters and recruiters, and trading between buyers and sellers. In this paper, we propose a model of two-way selection system, and present its analytical solution for the expectation of successful matching total and the regular pattern that the matching rate trends toward an inverse proportion to either the ratio between the two sides or the ratio of the state total to the smaller group's people number. The proposed model is verified by empirical data of the matchmaking fairs. Results indicate that the model well predicts this typical real-world two-way selection behavior to the bounded error extent, thus it is helpful for understanding the dynamics mechanism of the real-world two-way selection system.
The Asymptotic Standard Errors of Some Estimates of Uncertainty in the Two-Way Contingency Table
Brown, Morton B.
1975-01-01
Estimates of conditional uncertainty, contingent uncertainty, and normed modifications of contingent uncertainity have been proposed for the two-way contingency table. The asymptotic standard errors of the estimates are derived. (Author)
RUSSIAN-ENGLISH INTERACTIONS AS A TWO-WAY CHANNEL OF LINGUISTIC EXCHANGE
PROTSENKO EKATERINA ALEXANDROVNA
2015-01-01
Full Text Available The article is devoted to the problem of Russian-English interactions during the last decades. Linguistic exchange is considered as a two- way channel of intercultural communication.
Improvement of two-way continuous-variable quantum key distribution with virtual photon subtraction
Zhao, Yijia; Zhang, Yichen; Li, Zhengyu; Yu, Song; Guo, Hong
2017-08-01
We propose a method to improve the performance of two-way continuous-variable quantum key distribution protocol by virtual photon subtraction. The virtual photon subtraction implemented via non-Gaussian post-selection not only enhances the entanglement of two-mode squeezed vacuum state but also has advantages in simplifying physical operation and promoting efficiency. In two-way protocol, virtual photon subtraction could be applied on two sources independently. Numerical simulations show that the optimal performance of renovated two-way protocol is obtained with photon subtraction only used by Alice. The transmission distance and tolerable excess noise are improved by using the virtual photon subtraction with appropriate parameters. Moreover, the tolerable excess noise maintains a high value with the increase in distance so that the robustness of two-way continuous-variable quantum key distribution system is significantly improved, especially at long transmission distance.
Physical Layer Security for Two-Way Untrusted Relaying with Friendly Jammers
Zhang, Rongqing; Han, Lingyang song Zhu; Jiao, Bingli
2012-01-01
In this paper, we consider a two-way relay network where two sources can communicate only through an untrusted intermediate relay, and investigate the physical layer security issue of this two-way relay scenario. Specifically, we treat the intermediate relay as an eavesdropper from which the information transmitted by the sources needs to be kept secret, despite the fact that its cooperation in relaying this information is essential. We indicate that a non-zero secrecy rate is indeed achievab...
K B Athreya
2009-09-01
It is shown that (i) every probability density is the unique maximizer of relative entropy in an appropriate class and (ii) in the class of all pdf that satisfy $\\int fh_id_=_i$ for $i=1,2,\\ldots,\\ldots k$ the maximizer of entropy is an $f_0$ that is proportional to $\\exp(\\sum c_i h_i)$ for some choice of $c_i$. An extension of this to a continuum of constraints and many examples are presented.
Alsharoa, Ahmad M.
2014-02-01
In this letter, we consider a multiple-input multiple-output two-way cognitive radio system under a spectrum sharing scenario, where primary and secondary users operate on the same frequency band. The secondary terminals aims to exchange different messages with each other using multiple relays where each relay employs an amplify-and-forward strategy. The main objective of our work is to maximize the secondary sum rate allowed to share the spectrum with the primary users by respecting a primary user tolerated interference threshold. In this context, we derive an analytical expression of the optimal power allocated to each antenna of the terminals. We then discuss the impact of some system parameters on the performance in the numerical result section. © 2012 IEEE.
Zhang, Yichen; Li, Zhengyu; Zhao, Yijia; Yu, Song; Guo, Hong
2017-02-01
We analyze the security of the two-way continuous-variable quantum key distribution protocol in reverse reconciliation against general two-mode attacks, which represent all accessible attacks at fixed channel parameters. Rather than against one specific attack model, the expression of secret key rates of the two-way protocol are derived against all accessible attack models. It is found that there is an optimal two-mode attack to minimize the performance of the protocol in terms of both secret key rates and maximal transmission distances. We identify the optimal two-mode attack, give the specific attack model of the optimal two-mode attack and show the performance of the two-way protocol against the optimal two-mode attack. Even under the optimal two-mode attack, the performances of two-way protocol are still better than the corresponding one-way protocol, which shows the advantage of making double use of the quantum channel and the potential of long-distance secure communication using a two-way protocol.
Trangmar, Steven J; Chiesa, Scott T; Stock, Christopher G
2014-01-01
cerebral artery velocity (MCA Vmean), arterial-venous differences and blood temperature in 10 trained males during incremental cycling to exhaustion in the heat (35°C) in control, dehydrated and rehydrated states. Dehydration reduced body mass (75.8 ± 3 vs. 78.2 ± 3 kg), increased internal temperature (38......Intense exercise is associated with a reduction in cerebral blood flow (CBF), but regulation of CBF during strenuous exercise in the heat with dehydration is unclear. We assessed internal (ICA) and common carotid artery (CCA) haemodynamics (indicative of CBF and extra-cranial blood flow), middle...... venous noradrenaline, and falling arterial carbon dioxide tension (P aCO 2) (R(2) ≥ 0.41, P ≤ 0.01) whereas CCA flow and conductance were related to elevated blood temperature. In conclusion, dehydration accelerated the decline in CBF by decreasing P aCO 2 and enhancing vasoconstrictor activity. However...
Clausen, Lasse Røngaard
2015-01-01
analysis of two biorefineries integrating water electrolysis for the production of methanol. In both plants, torrefied woody biomass is supplied to an entrained flow gasifier, but in one of the plants, the torrefaction process occurs on-site, as it is integrated with the entrained flow gasification process....... The analysis shows that the biorefinery with integrated torrefaction has a higher biomass to methanol energy ratio (136% vs. 101%) as well as higher total energy efficiency (62% vs. 56%). By comparing with two identical biorefineries without electrolysis, it is concluded that the biorefinery with integrated...... torrefaction benefits most from the integration of electrolysis....
中国双向投资问题研究%The Study on China's Two-way Investment
李辉; 张荣
2012-01-01
随着经济全球化迅猛发展和一国经济实力的增强，双向投资成为越来越多国家参与国际分工和世界经济竞争的重要选择。近年来，中国已经成为国际直接投资流动中的一支重要力量，无论是吸收外商直接投资还是对外直接投资，中国都取得了巨大成就。但是，中国双向投资在存量结构、产业结构、区位结构以及投资方式结构上都有一定的差距。因此，从全球产业链的角度审视双向投资，调整中国双向投资结构失衡问题，统一双向投资政策，培育具有国际竞争力的中国跨国公司，是解决中国双向投资结构失衡的问题所在。%With the rapid development of economic globalization and strengthens of a country's economy, two-way investment has been an important choice for a growing number of countries to participate in the interna- tional division and economic competition in the world. In recent years, China has played an important role in in- ternational direct investment flow and has made great achievements in both inward foreign direct investment and outward foreign direct investment; however, China's two-way investment has demonstrated a disparity between stock structure, industrial structure, regional structure and investment mode. Therefore, from the perspective of the global industrial chain, the keys to China's two-way investment are to adjust the structure of China's two- way investment imbalances, to integrate two-way investment policy and to foster competitiveness of China's transnational corporations.
Clausen, Lasse Røngaard
2015-01-01
double the biofuel production per biomass input by converting almost all of the carbon in the biomass feed to carbon stored in the biofuel product. Water or steam electrolysis can supply the hydrogen to the biorefinery and also the oxygen for the gasifier. This paper presents the design and thermodynamic....... The analysis shows that the biorefinery with integrated torrefaction has a higher biomass to methanol energy ratio (136% vs. 101%) as well as higher total energy efficiency (62% vs. 56%). By comparing with two identical biorefineries without electrolysis, it is concluded that the biorefinery with integrated...... analysis of two biorefineries integrating water electrolysis for the production of methanol. In both plants, torrefied woody biomass is supplied to an entrained flow gasifier, but in one of the plants, the torrefaction process occurs on-site, as it is integrated with the entrained flow gasification process...
Hash-and-Forward Relaying for Two-Way Relay Channel
Yilmaz, Erhan
2011-01-01
This paper considers a communication network comprised of two nodes, which have no mutual direct communication links, communicating two-way with the aid of a common relay node (RN), also known as separated two-way relay (TWR) channel. We first recall a cut-set outer bound for the set of rates in the context of this network topology assuming full-duplex transmission capabilities. Then, we derive a new achievable rate region based on hash-and-forward (HF) relaying where the RN does not attempt to decode but instead hashes its received signal, and show that under certain channel conditions it coincides with Shannon's inner-bound for the two-way channel [1]. Moreover, for binary adder TWR channel with additive noise at the nodes and the RN we provide a detailed capacity achieving coding scheme based on structure codes.
Relativity on a two-way moving sidewalk. Relativite sur un tapis roulant
Jaccarini, Antoine (College Merici, Quebec (Canada). Dept. des Sciences)
1989-01-01
Some classical thought experiments in Special Relativity are performed on a two-way moving sidewalk. Since each of the two sides moves at constant speed, this device provides a simple, intuitive way to illustrate relative velocity, time dilation, and length contraction. It should, therefore allow for a better understanding of the basic concepts of the theory. Furthermore, being a closed system the two-way sidewalk exhibits some of the characteristics of a rotating disc, and might therefore be helpful in an introduction to General Relativity. (author).
Mia Angeline
2013-03-01
Full Text Available The article investigates the internal communication in the two branches of foreign banks in Kelapa Gading from the perspectives of two-way symmetrical communication and internal marketing. The second problem investigated is the effectiveness of the use of email as a means of internal communication. Data were collected through interviews and literature. The results showed that the perception of employees not in accordance with the concept of two-way communication and internal marketing, but this policy has led the organization to these concepts. In the use of email, employee perceptions still see that the email is an effective internal communication media despite having many weaknesses.
Cerf, Raphaël
2009-01-01
We consider the standard first passage percolation model in the rescaled graph $\\mathbb{Z}^d/n$ for $d\\geq 2$, and a domain $\\Omega$ of boundary $\\Gamma$ in $\\mathbb{R}^d$. Let $\\Gamma^1$ and $\\Gamma^2$ be two disjoint open subsets of $\\Gamma$, representing the parts of $\\Gamma$ through which some water can enter and escape from $\\Omega$. We investigate the asymptotic behaviour of the flow $\\phi_n$ through a discrete version $\\Omega_n$ of $\\Omega$ between the corresponding discrete sets $\\Gamma^1_n$ and $\\Gamma^2_n$. We prove that under some conditions on the regularity of the domain and on the law of the capacity of the edges, the lower large deviations of $\\phi_n/ n^{d-1}$ below a certain constant are of surface order.
The Promise and Potential of Two-Way Immersion in Catholic Schools
Fraga, Luis R.
2016-01-01
Two-Way Immersion (TWI) is a method of instruction designed to facilitate the learning of a second language by non-native speakers. Unlike traditional methods of teaching a second language, TWI is grounded in the equal presence, respect, and value of the two languages and their related cultures. Moreover, the goal of TWI is the building of…
Response of stiff piles to random two-way lateral loading
Bakmar, Christian LeBlanc; Byrne, B.W.; Houlsby, G. T.
2010-01-01
A model for predicting the accumulated rotation of stiff piles under random two-way loading is presented. The model is based on a strain superposition rule similar to Miner's rule and uses rainflow-counting to decompose a random time-series of varying loads into a set of simple load reversals...
Discussing Difference: Color-Blind Collectivism and Dynamic Dissonance in Two-Way Immersion Contexts
Stolte, Laurel
2017-01-01
This comparative case study (based on observational, interview, and picture-sort data) examines how teachers and students talk about cultural, linguistic, racial, and socioeconomic difference in two elementary Spanish-English two-way immersion programs. In addition, I analyze how those discourses are associated with both contextual conditions and…
A Mandarin/English Two-Way Immersion Program: Language Proficiency and Academic Achievement
Padilla, Amado M.; Fan, Lorraine; Xu, Xiaoqiu; Silva, Duarte
2013-01-01
A Mandarin/English two-way immersion elementary program is described from its inception and implementation through the fifth grade, the culminating year of the program. All students in all grades were assessed on their oral/listening, reading, and writing performance in Mandarin using program-created assessment measures. Fifth-grade students also…
Two-way immersion – a teaching/learning method for bi-/plurilingual communities?
Reseda Streb
2017-01-01
Full Text Available Two-way Immersion is a very significant educational method for bi-/plurilingual communities, because it concentrates on equalty of both partner languages and cultures. How does this method works in practice? What are the challenges and advantages for the language learning process? These are the questions to be discussed in the present article.
GENERALIZED CONFIDENCE REGIONS OF FIXED EFFECTS IN THE TWO-WAY ANOVA
Weiyan MU; Shifeng XIONG; Xingzhong XU
2008-01-01
The authors discuss the unbalanced two-way ANOVA model under heteroscedasticity. By taking the generalized approach, the authors derive the generalized p-values for testing the equality of fixed effects and the generalized confidence regions for these effects. The authors also provide their frequentist properties in large-sample cases. Simulation studies show that the generalized confidence regions have good coverage probabilities.
Two-Way Tables: Issues at the Heart of Statistics and Probability for Students and Teachers
Watson, Jane; Callingham, Rosemary
2014-01-01
Some problems exist at the intersection of statistics and probability, creating a dilemma in relation to the best approach to assist student understanding. Such is the case with problems presented in two-way tables representing conditional information. The difficulty can be confounded if the context within which the problem is set is one where…
Arora, Ridhi; Rangnekar, Santosh
2016-01-01
In this study, we examined potential two-way interaction effects of the Big Five personality traits extraversion and openness to experience on career commitment measured in terms of three components of career identity, career resilience, and career planning. Participants included 450 managers from public and private sector organizations in North…
Zenaty, Jayne W.; And Others
1979-01-01
Describes a minicomputer software system for the administration of instructional programs combining interactive cable television and computer aided instruction for potentially large populations at relatively low cost. Both basic two-way cable television technology and the system developed by Michigan State University are discussed. (Author)
Two-way causation in life satisfaction research : Structural equation models with granger causation
Headey, Bruce; Muffels, R.J.A.
2014-01-01
Two-way causation issues are the bete noire of life satisfaction research. As acknowledged in several landmark reviews, many variables routinely reported as causes or determinants of life satisfaction could equally well be consequences, or perhaps both causes and consequences (Diener, 1984; Diener,
Languages across Borders: Social Network Development in an Adolescent Two-Way Dual-Language Program
Kibler, Amanda K.; Atteberry, Allison; Hardigree, Christine N.; Salerno, April S.
2015-01-01
Background/Context: Two-way dual-language programs have become an increasingly popular educational model in the United States for language minority and majority speakers, with a small but growing number of programs at the high school level. Little is known, however, about how adolescents' social networks develop in the contexts of these programs.…
Analysis of Two Way Simply Supported Slabs With Central Sunk Using Finite Element Method
Chiranjeevi. M
2014-09-01
Full Text Available Majority of the sunken slabs are constructed with supporting beams, which leads to the uneconomy of the structure and difficult in arrangement of the centering work. In this view, it is considered to analyze a two way simply supported slab of different thicknesses with central sunk having one sunk depths.The objective of the paper is to analyze a two way simply supported slab having different thicknesses of 125,150,175,and 200mm with central sunk having depths of 250mm using Finite Element Analysis. This study significantly concludes that, adopting FE analysis using STAAD Pro for analysis of two-way sunken slab is advisable. By using FE analysis using STAAD Pro, we can avoid tedious and lengthy procedure of manual methods. From the chosen sunken slab it was observed that, there is decrease in sagging moments for sunk size of 0.25lx x 0.25ly with respect to two way slab without sunk.
Sullivan, Michael; And Others
In three southwestern states, grassroots movements of citizens, educators, and local businesses developed and implemented two-way interactive television projects in their schools and communities. A descriptive multiple case study design was used to examine six project sites in New Mexico, Texas, and Oklahoma. Research questions were categorized in…
More Powerful Tests of Simple Interaction Contrasts in the Two-Way Factorial Design
Hancock, Gregory R.; McNeish, Daniel M.
2017-01-01
For the two-way factorial design in analysis of variance, the current article explicates and compares three methods for controlling the Type I error rate for all possible simple interaction contrasts following a statistically significant interaction, including a proposed modification to the Bonferroni procedure that increases the power of…
A Mandarin/English Two-Way Immersion Program: Language Proficiency and Academic Achievement
Padilla, Amado M.; Fan, Lorraine; Xu, Xiaoqiu; Silva, Duarte
2013-01-01
A Mandarin/English two-way immersion elementary program is described from its inception and implementation through the fifth grade, the culminating year of the program. All students in all grades were assessed on their oral/listening, reading, and writing performance in Mandarin using program-created assessment measures. Fifth-grade students also…
Mechanical Verification of a Two-Way Sliding Window Protocol (Full version including proofs)
Badban, Bahareh; Fokkink, Wan; Pol, van de Jaco
2008-01-01
We prove the correctness of a two-way sliding window protocol with piggybacking, where the acknowledgments of the latest received data are attached to the next data transmitted back into the channel. The window size of both parties are considered to be finite, though they can be of different sizes.
Cervantes-Soon, Claudia G.; Dorner, Lisa; Palmer, Deborah; Heiman, Dan; Schwerdtfeger, Rebecca; Choi, Jinmyung
2017-01-01
This chapter reviews critical areas of research on issues of equity/equality in the highly proclaimed and exponentially growing model of bilingual education: two-way immersion (TWI). There is increasing evidence that TWI programs are not living up to their ideal to provide equal access to educational opportunity for transnational emergent…
Improving Bilingual Service Delivery in Catholic Schools through Two-Way Immersion
Scanlan, Martin; Zehrbach, Gareth
2010-01-01
Catholic elementary schools underserve Latino students, especially those who are bilingual. This paper presents a conceptual argument for Catholic elementary schools to improve this by pursuing the two-way immersion model of bilingual service delivery in Spanish and English. The argument is presented in three stages. First, we show that Catholic…
Two-Way Bilingual Immersion Programs: Toward a More Inclusive Agenda in Bilingual Education.
Reyes, Sharon Adelman
2001-01-01
Examines essential components of quality two-way bilingual immersion programs. Discusses language acquisition research underlying context-embedded content-area instruction in a second language; research on the benefits of bilingualism in terms of academic, cognitive, and metalinguistic development; and the link between bilingualism and positive…
Advanced two-way satellite frequency transfer by carrier-phase and carrier-frequency measurements
Fujieda, Miho; Gotoh, Tadahiro; Amagai, Jun
2016-06-01
Carrier-phase measurement is one of the ways to improve the measurement resolution of two-way satellite frequency transfer. We introduce two possible methods for carrier-phase measurement: direct carrier-phase detection identified by Two-Way Carrier-Phase (TWCP) and the use of carrier-frequency information identified by Two-Way Carrier Frequency (TWCF). We performed the former using an arbitrary waveform generator and an analog-to-digital sampler and the latter using a conventional modem. The TWCF measurement using the modem had a resolution of 10-13 and the result agreed with that obtained by GPS carrier-phase frequency transfer in a 1500 km baseline. The measurement accuracy may have been limited by the poor frequency resolution of the modem; however, the TWCF measurement was able to improve the stability of conventional two-way satellite frequency transfer. Additionally, we show that the TWCP measurement system has the potential to achieve a frequency stability of 10-17.
Two-Way Bilingual Education: Students Learning through Two Languages. Final Report.
Christian, Donna; Montone, Chris; Carranza, Isolda; Lindholm, Kathryn; Proctor, Patrick
The report presents results of a study of elementary and secondary school two-way bilingual immersion programs that focused on the program and contextual factors affecting student learning, student and teacher language use in the classroom, and teaching strategies used to promote target language use and increase language proficiency. The study…
Language Choice & Language Power: Children's Use of Korean & English in a Two-Way Immersion Program
Lee, Soyong
2014-01-01
In this article, the author explores the phenomenon of children's language choice and language use in a Korean-English two-way immersion (TWI) program. She does so by drawing on situations in which the children spoke of the principles guiding their choice of languages, and instances in which they voluntarily adopted Korean as the means of…
General immunity and superadditivity of two-way Gaussian quantum cryptography
Ottaviani, Carlo; Pirandola, Stefano
2016-03-01
We consider two-way continuous-variable quantum key distribution, studying its security against general eavesdropping strategies. Assuming the asymptotic limit of many signals exchanged, we prove that two-way Gaussian protocols are immune to coherent attacks. More precisely we show the general superadditivity of the two-way security thresholds, which are proven to be higher than the corresponding one-way counterparts in all cases. We perform the security analysis first reducing the general eavesdropping to a two-mode coherent Gaussian attack, and then showing that the superadditivity is achieved by exploiting the random on/off switching of the two-way quantum communication. This allows the parties to choose the appropriate communication instances to prepare the key, accordingly to the tomography of the quantum channel. The random opening and closing of the circuit represents, in fact, an additional degree of freedom allowing the parties to convert, a posteriori, the two-mode correlations of the eavesdropping into noise. The eavesdropper is assumed to have no access to the on/off switching and, indeed, cannot adapt her attack. We explicitly prove that this mechanism enhances the security performance, no matter if the eavesdropper performs collective or coherent attacks.
General immunity and superadditivity of two-way Gaussian quantum cryptography.
Ottaviani, Carlo; Pirandola, Stefano
2016-03-01
We consider two-way continuous-variable quantum key distribution, studying its security against general eavesdropping strategies. Assuming the asymptotic limit of many signals exchanged, we prove that two-way Gaussian protocols are immune to coherent attacks. More precisely we show the general superadditivity of the two-way security thresholds, which are proven to be higher than the corresponding one-way counterparts in all cases. We perform the security analysis first reducing the general eavesdropping to a two-mode coherent Gaussian attack, and then showing that the superadditivity is achieved by exploiting the random on/off switching of the two-way quantum communication. This allows the parties to choose the appropriate communication instances to prepare the key, accordingly to the tomography of the quantum channel. The random opening and closing of the circuit represents, in fact, an additional degree of freedom allowing the parties to convert, a posteriori, the two-mode correlations of the eavesdropping into noise. The eavesdropper is assumed to have no access to the on/off switching and, indeed, cannot adapt her attack. We explicitly prove that this mechanism enhances the security performance, no matter if the eavesdropper performs collective or coherent attacks.
Coupled Two-Way Clustering Analysis of Breast Cancer and Colon Cancer Gene Expression Data
Getz, G; Kela, I; Domany, E; Notterman, D A; Getz, Gad; Gal, Hilah; Kela, Itai; Domany, Eytan; Notterman, Dan A.
2003-01-01
We present and review Coupled Two Way Clustering, a method designed to mine gene expression data. The method identifies submatrices of the total expression matrix, whose clustering analysis reveals partitions of samples (and genes) into biologically relevant classes. We demonstrate, on data from colon and breast cancer, that we are able to identify partitions that elude standard clustering analysis.
An experimental study of the two-way shape memory effect in a NiTi tubular actuator
Yoo, Young Ik; Lee, Jung Ju; Lee, Chang Ho; Lim, Jae Hyuk
2010-12-01
In this paper, the two-way shape memory effect (TWSME) in a Ti-54.5 Ni(wt%) alloy was investigated experimentally to develop a NiTi linear actuator. The two-way shape memory effect was induced through a compressive shape memory cycle comprising four steps: (1) loading to maximum deformation; (2) unloading (3) heating and (4) cooling. Six types of specimen (one solid cylindrical and five tubular) were used to obtain the two-way shape memory strain and two-way recovery stress and to evaluate the actuating capacity. The two-way actuating strain showed a saturated tendency after several training cycles for the same maximum deformation. A maximum value of the two-way strain was obtained for 7% of maximum deformation, independently of the geometry of the tubular specimens. The two-way strains obtained by the shape memory cycles and two-way recovery stress linearly increase as a function of the maximum deformation and the two-way strain, respectively, and the geometry of specimen affects the two-way recovery stress. Although the results show that sufficient recovery stress can be generated by either the two-way shape memory process or by the one-way shape memory process, the two-way shape memory process can be applied more conveniently to actuating applications.
Two-way nesting in split-explicit ocean models: Algorithms, implementation and validation
Debreu, Laurent; Marchesiello, Patrick; Penven, Pierrick; Cambon, Gildas
2012-06-01
A full two-way nesting approach for split-explicit, free surface ocean models is presented. It is novel in three main respects: the treatment of grid refinement at the fast mode (barotropic) level; the use of scale selective update schemes; the conservation of both volume and tracer contents via refluxing. An idealized application to vortex propagation on a β plane shows agreement between nested and high resolution solutions. A realistic application to the California Current System then confirm these results in a complex configuration. The selected algorithm is now part of ROMS_AGRIF. It is fully consistent with ROMS parallel capabilities on both shared and distributed memory architectures. The nesting implementation authorizes several nesting levels and several grids at any particular level. This operational capability, combined with the inner qualities of our two-way nesting algorithm and generally high-order accuracy of ROMS numerics, allow for realistic simulation of coastal and ocean dynamics at multiple, interacting scales.
Improved two-way six-state protocol for quantum key distribution
Shaari, J.S., E-mail: jesni_shamsul@yahoo.com [Faculty of Science, International Islamic University Malaysia (IIUM), Jalan Sultan Ahmad Shah, Bandar Indera Mahkota, 25200 Kuantan, Pahang (Malaysia); Bahari, Asma' Ahmad [Faculty of Science, International Islamic University Malaysia (IIUM), Jalan Sultan Ahmad Shah, Bandar Indera Mahkota, 25200 Kuantan, Pahang (Malaysia)
2012-10-01
A generalized version for a qubit based two-way quantum key distribution scheme was first proposed in the paper [Phys. Lett. A 358 (2006) 85] capitalizing on the six quantum states derived from three mutually unbiased bases. While boasting of a higher level of security, the protocol was not designed for ease of practical implementation. In this work, we propose modifications to the protocol, resulting not only in improved security but also in a more efficient and practical setup. We provide comparisons for calculated secure key rates for the protocols in noisy and lossy channels. -- Highlights: ► Modification for efficient generalized two-way QKD is proposed. ► Calculations include secure key rates in noisy and lossy channels for selected attack scenario. ► Resulting proposal provides for higher secure key rate in selected attack scheme.
Thermally Activated Composite with Two-Way and Multi-Shape Memory Effects
Bernard Durand
2013-09-01
Full Text Available The use of shape memory polymer composites is growing rapidly in smart structure applications. In this work, an active asymmetric composite called “controlled behavior composite material (CBCM” is used as shape memory polymer composite. The programming and the corresponding initial fixity of the composite structure is obtained during a bending test, by heating CBCM above thermal glass transition temperature of the used Epoxy polymer. The shape memory properties of these composites are investigated by a bending test. Three types of recoveries are conducted, two classical recovery tests: unconstrained recovery and constrained recovery, and a new test of partial recovery under load. During recovery, high recovery displacement and force are produced that enables the composite to perform strong two-way actuations along with multi-shape memory effect. The recovery force confirms full recovery with two-way actuation even under a high load. This unique property of CBCM is characterized by the recovered mechanical work.
NONE
2000-07-01
When Norway and Sweden experience a period of cold at the same time, then the electrical network may fail to supply the required load. Since this situation prevails, on average, only a few hours each winter, increasing the supply capacity is not the way of solving the problem. Import from the continent would be hampered by bottlenecks in the network. The problem could be solved if there was two-way communication between supplier and customer. Then higher prices during peak load periods would make the end-users turn off unnecessary loads during such critical periods. Another solution would be to establish agreements with the end-users on load disconnection. Trondheim Energiverk Nett AS in Norway is evaluating the introduction of two-way communication with all their end-users.
Wei, Shigang; Zhang, Huihui; Wang, Yeqiang; Wang, Lu; Li, Xueyuan; Wang, Yinghua; Zhang, Hanqi; Xu, Xu; Shi, Yuhua
2011-07-22
The ultrasonic nebulization extraction-heating gas flow transfer coupled with headspace single drop microextraction (UNE-HGFT-HS-SDME) was developed for the extraction of essential oil from Zanthoxylum bungeanum Maxim. The gas chromatography-mass spectrometry was applied to the determination of the constituents in the essential oil. The contents of the constituents from essential oil obtained by the proposed method were found to be more similar to those obtained by hydro-distillation (HD) than those obtained by ultrasonic nebulization extraction coupled with headspace single drop microextraction (UNE-HS-SDME). The heating gas flow was firstly used in the analysis of the essential oil to transfer the analytes from the headspace to the solvent microdrop. The relative standard deviations for determining the five major constituents were in the range from 1.5 to 6.7%. The proposed method is a fast, sensitive, low cost and small sample consumption method for the determination of the volatile and semivolatile constituents in the plant materials.
Two-way nesting in split-explicit ocean models : algorithms, implementation and validation
2012-01-01
A full two-way nesting approach for split-explicit, free surface ocean models is presented. It is novel in three main respects: the treatment of grid refinement at the fast mode (barotropic) level; the use of scale selective update schemes; the conservation of both volume and tracer contents via refluxing. An idealized application to vortex propagation on a beta plane shows agreement between nested and high resolution solutions. A realistic application to the California Current System then co...
Two-Way Gene Interaction From Microarray Data Based on Correlation Methods
Alavi Majd, Hamid; Talebi, Atefeh; Gilany, Kambiz; Khayyer, Nasibeh
2016-01-01
Background Gene networks have generated a massive explosion in the development of high-throughput techniques for monitoring various aspects of gene activity. Networks offer a natural way to model interactions between genes, and extracting gene network information from high-throughput genomic data is an important and difficult task. Objectives The purpose of this study is to construct a two-way gene network based on parametric and nonparametric correlation coefficients. The first step in const...
Student and Teacher Oral Language Use in a Two-Way Spanish/English Immersion School
Ballinger, Susan; Lyster, Roy
2011-01-01
This study examines the Spanish use of students and teachers at a US two-way immersion school. Students and teachers from Grades 1, 3, and 8 (5-6-year-olds, 7-8-years-olds, and 12-13-year-olds, respectively) were observed and interviewed, and students completed questionnaires to determine what factors influenced their language of choice and their…
An investigation of two-way text messaging use with deaf students at the secondary level.
Akamatsu, C Tane; Mayer, Connie; Farrelly, Shona
2006-01-01
Deaf and hard-of-hearing students are often delayed in developing their independent living skills because of parental restrictions on activities outside the home due to worries about their child's inability to communicate, their whereabouts, and their general safety. Recent accounts of the use of two-way text messagers suggests that, like electronic mail, distance communication problems that have long plagued deaf people may be ameliorated--by the use of such technology (M. R. Power & D. Power, 2004; S. S. Rhone & Cox News Service, 2002). This project was designed as an initial foray into investigating the use of two-way text messaging technology as a way of increasing the independence of deaf adolescents and reducing their parents' anxiety about their safety and responsibility. All the deaf and hard-of-hearing students in the deaf and hard-of-hearing programs at two urban high schools (ages 13-19), the staff of the deaf departments at these two schools, and the parents/guardians of the students participated in this study. Preuse surveys, postuse surveys, and monthly statistics on the number of times each pager was used enabled us to chart how often the participants used the technology. The data were used to identify concerns that parents have about student independence and safety, the extent to which deaf students engage in independent activities, and expectations surrounding how two-way text messaging use might increase independence and literacy skills. The data collected on this project to date confirm that two-way text messaging technology is indeed useful for deaf adolescents and helps alleviate some of the concerns that have kept them from developing independence as quickly or readily as their hearing peers. The potential policy implications for this research are discussed.
The application of laser two-way depletion model in AVLIS for uranium
Changjiang Yu [The Institution of Physics and Chemistry Engineering in Nuclear Industry, Tianjin (China); Min Yan; Dewu Wang; Chuntong Ying [Tsinghua Univ., Beijing, BJ (China). Dept. of Engineering Physics
1996-12-31
We propose a two-way depletion model to be applied in AVLIS, and the problem of small isotope shifts is avoided. The higher selectivity and lower waste composition can be obtained disregarding the power broadening effect. This model makes the product and waste compositions ({sup C} p and {sup C} w) of AVLIS satisfy the requirements {sup c} p > 3.5%, {sup C} w < 0.25 easily. (author) 5 refs., 5 figs., 1 tab.
A Rhetorical Grammar Analysis of Two Ways of Seeing a River
李永仙
2016-01-01
“Two Ways of Seeing a River”, an excerpt from Life on the Mississippi, written by Mark Twain and published in 1883, is a short but effective comparison essay in which Twain contrasts his then-and-now views of the Mississippi River. The rhetorical strategies and devices that are used by Twain to effectively communicate his messages to readers will be analyzed from the sentential level: vocabulary and phrases, and the figure of speech.
Two-way regularization for MEG source reconstruction via multilevel coordinate descent
Siva Tian, Tian
2013-12-01
Magnetoencephalography (MEG) source reconstruction refers to the inverse problem of recovering the neural activity from the MEG time course measurements. A spatiotemporal two-way regularization (TWR) method was recently proposed by Tian et al. to solve this inverse problem and was shown to outperform several one-way regularization methods and spatiotemporal methods. This TWR method is a two-stage procedure that first obtains a raw estimate of the source signals and then refines the raw estimate to ensure spatial focality and temporal smoothness using spatiotemporal regularized matrix decomposition. Although proven to be effective, the performance of two-stage TWR depends on the quality of the raw estimate. In this paper we directly solve the MEG source reconstruction problem using a multivariate penalized regression where the number of variables is much larger than the number of cases. A special feature of this regression is that the regression coefficient matrix has a spatiotemporal two-way structure that naturally invites a two-way penalty. Making use of this structure, we develop a computationally efficient multilevel coordinate descent algorithm to implement the method. This new one-stage TWR method has shown its superiority to the two-stage TWR method in three simulation studies with different levels of complexity and a real-world MEG data analysis. © 2013 Wiley Periodicals, Inc., A Wiley Company.
Damage Assessment of Two-Way Bending RC Slabs Subjected to Blast Loadings
Haokai Jia
2014-01-01
Full Text Available Terrorist attacks on vulnerable structures and their individual structural members may cause considerable damage and loss of life. However, the research work on response and damage analysis of single structural components, for example, a slab to blast loadings, is limited in the literature and this is necessary for assessing its vulnerability. This study investigates the blast response and damage assessment of a two-way bending reinforced concrete (RC slab subjected to blast loadings. Numerical modeling and analysis are carried out using the commercial finite element code LS-DYNA 971. A damage assessment criterion for the two-way bending RC slab is defined based on the original and residual uniformly distributed load-carrying capacity. Parametric studies are carried out to investigate the effects of explosive weight and explosive position on the damage mode of the two-way RC slab. Some design parameters, such as the boundary conditions and the negative reinforcement steel bar length, are also discussed. The illustrated results show that the proposed criterion can apply to all failure modes. The damage assessment results are more accurate than the ones due to the conventional deformation criterion.
Two-way text messaging: an interactive mobile learning environment in higher education
H.K. Salinda Premadasa
2016-11-01
Full Text Available Short messaging service (SMS is perhaps the most popular mobile technology prevalent among students in higher education due to its ubiquitous nature and the capability of two-way communication. However, a major limitation in two-way text messaging is sending back a part of received data with the reply message. This limitation results in users of a mobile learning environment being unable to reply back to the correct destination. This article presents a two-way text messaging system that can be integrated into a learning management system (LMS to provide an interactive learning experience to the user community. Initially, a database is integrated into the LMS that holds message information such as recipient's phone number, message body and user data header. A specific port associated with the SMS is used to conceal and exchange data of a particular course unit. Subsequently, software in the student's mobile device captures this message and sends back the reply message to the appropriate course unit allowing both teachers and students to view messages sent and replies received pertaining to a particular course. Results indicate the educational impact of the proposed system in improving the learning environment and benefits it offers to the community in a campus-wide implementation.
Multiantenna relay beamforming design for QoS discrimination in two-way relay networks.
Xiong, Ke; Zhang, Yu; Li, Dandan; Chang, Chih-Yung; Zhong, Zhangdui
2013-01-01
This paper investigates the relay beamforming design for quality of service (QoS) discrimination in two-way relay networks. The purpose is to keep legitimate two-way relay users exchange their information via a helping multiantenna relay with QoS guarantee while avoiding the exchanged information overhearing by unauthorized receiver. To this end, we propose a physical layer method, where the relay beamforming is jointly designed with artificial noise (AN) which is used to interfere in the unauthorized user's reception. We formulate the joint beamforming and AN (BFA) design into an optimization problem such that the received signal-to-interference-ratio (SINR) at the two legitimate users is over a predefined QoS threshold while limiting the received SINR at the unauthorized user which is under a certain secure threshold. The objective of the optimization problem is to seek the optimal AN and beamforming vectors to minimize the total power consumed by the relay node. Since the optimization problem is nonconvex, we solve it by using semidefinite program (SDP) relaxation. For comparison, we also study the optimal relay beamforming without using AN (BFO) under the same QoS discrimination constraints. Simulation results show that both the proposed BFA and BFO can achieve the QoS discrimination of the two-way transmission. However, the proposed BFA yields significant power savings and lower infeasible rates compared with the BFO method.
Damage Assessment of Two-Way Bending RC Slabs Subjected to Blast Loadings
Jia, Haokai; Wu, Guiying
2014-01-01
Terrorist attacks on vulnerable structures and their individual structural members may cause considerable damage and loss of life. However, the research work on response and damage analysis of single structural components, for example, a slab to blast loadings, is limited in the literature and this is necessary for assessing its vulnerability. This study investigates the blast response and damage assessment of a two-way bending reinforced concrete (RC) slab subjected to blast loadings. Numerical modeling and analysis are carried out using the commercial finite element code LS-DYNA 971. A damage assessment criterion for the two-way bending RC slab is defined based on the original and residual uniformly distributed load-carrying capacity. Parametric studies are carried out to investigate the effects of explosive weight and explosive position on the damage mode of the two-way RC slab. Some design parameters, such as the boundary conditions and the negative reinforcement steel bar length, are also discussed. The illustrated results show that the proposed criterion can apply to all failure modes. The damage assessment results are more accurate than the ones due to the conventional deformation criterion. PMID:25121134
WRF-CMAQ two-way coupled system with aerosol feedback: software development and preliminary results
D. C. Wong
2012-03-01
Full Text Available Air quality models such as the EPA Community Multiscale Air Quality (CMAQ require meteorological data as part of the input to drive the chemistry and transport simulation. The Meteorology-Chemistry Interface Processor (MCIP is used to convert meteorological data into CMAQ-ready input. Key shortcoming of such one-way coupling include: excessive temporal interpolation of coarsely saved meteorological input and lack of feedback of atmospheric pollutant loading on simulated dynamics. We have developed a two-way coupled system to address these issues. A single source code principle was used to construct this two-way coupling system so that CMAQ can be consistently executed as a stand-alone model or part of the coupled system without any code changes; this approach eliminates maintenance of separate code versions for the coupled and uncoupled systems. The design also provides the flexibility to permit users: (1 to adjust the call frequency of WRF and CMAQ to balance the accuracy of the simulation versus computational intensity of the system, and (2 to execute the two-way coupling system with feedbacks to study the effect of gases and aerosols on short wave radiation and subsequent simulated dynamics. Details on the development and implementation of this two-way coupled system are provided. When the coupled system is executed without radiative feedback, computational time is virtually identical when using the Community Atmospheric Model (CAM radiation option and a slightly increased (~8.5% when using the Rapid Radiative Transfer Model for GCMs (RRTMG radiation option in the coupled system compared to the offline WRF-CMAQ system. Once the feedback mechanism is turned on, the execution time increases only slightly with CAM but increases about 60% with RRTMG due to the use of a more detailed Mie calculation in this implementation of feedback mechanism. This two-way model with radiative feedback shows noticeably reduced bias in simulated surface shortwave
An Inequality Concerning Quantitative Duality in an Asymmetry Two-Way Interferometer
HAN Yang; WU Chun-Wang; WU Wei; CHEN Ping-Xing; LI Cheng-Zu
2009-01-01
@@ We reinvestigate the measures concerning the notion of duality of a quantum system (the "quanton") in an asymmetry two-way interferometer. A new measure of the which-way information is introduced, which is based on the fidelity F instead of the trace distance Q of the final states of the which-way detector. An improved inequality is derived to be V2 ≤ (R20-P2)(1-F)2, which is more stringent than the previous one of V2 ≤ (1-P2)(1-Q2).
Performance analysis for a two-way relaying power line network with analog network coding
Yu-wen QIAN; Meng TIAN; Xue JIANG; Hua-ju SONG; Feng SHU; Jun LI
2015-01-01
In this paper, we investigate a two-way relaying power line communication (PLC) network with analog network coding. We focus on the analysis of the system outage probability, symbol error rate, and average capacity. Specifically, we first derive the probability density function (PDF) of the received signal-to-noise ratio (SNR) with a closed form, by exploiting the statistical properties of the PLC channel. Then with the help of this PDF, we develop the outage probability, symbol error rate, and average capacity with closed forms, based on the Hermite polynomial. Simulations show that the derived analytical results are consistent with those by Monte Carlo simulation.
Parametric down-conversion with local operation and two-way classical communication
Liu Qiang; Tan Yong-Gang
2011-01-01
The decoy-state quantum key distribution protocol suggested by Adachi et al.(Phys. Rev. Lett. 99 180503(2007))is proven to be secure and feasible with current techniques. It owns two attractive merits, i.e,its longer secure transmission distance and more convenient operation design. In this paper, we first improve the protocol with the aid of local operation and two-way classical communication(2-LOCC). After our modifications, the secure transmission distance is increased by about 20 km, which will make the protocol more practicable.
On the performance of spectrum sharing systems with two-way relaying and multiuser diversity
Yang, Liang
2012-08-01
In this letter, we consider a spectrum sharing network with two-way relaying and multi-user diversity. More specifically, one secondary transmitter with the best channel quality is selected and splits its partial power to relay its received signals to the primary users by using the amplify-and-forward relaying protocol. We derive a tight approximation for the resulting outage probability. Based on this formula, the performance of the spectral sharing region and the cell coverage are analyzed. Numerical results are given to verify our analysis and are discussed to illustrate the advantages of our newly proposed scheme. © 1997-2012 IEEE.
Relay selection and resource allocation for two-way DF-AF cognitive radio networks
Alsharoa, Ahmad M.
2013-08-01
In this letter, the problem of relay selection and optimal resource allocation for two-way relaying cognitive radio networks using half duplex amplify-and-forward and decode-and-forward protocols is investigated. The primary and secondary users are assumed to access the spectrum simultaneously, in a way that the interference introduced to the primary users should be below a certain tolerated limit. Dual decomposition and subgradient methods are used to find the optimal power allocation. A suboptimal approach based on a genetic algorithm is also presented. Simulation results show that the proposed suboptimal algorithm offers a performance close to the optimal performance with a considerable complexity saving. © 2013 IEEE.
Resource Allocation with Subcarrier Pairing in OFDMA Two-Way Relay Networks
Zhang, Hao; Tao, Meixia
2012-01-01
This study considers an orthogonal frequency-division multiple-access (OFDMA)-based multi-user two-way relay network where multiple mobile stations (MSs) communicate with a common base station (BS) via multiple relay stations (RSs). We study the joint optimization problem of subcarrier-pairing based relay-power allocation, relay selection, and subcarrier assignment. The problem is formulated as a mixed integer programming problem. By using the dual method, we propose an efficient algorithm to solve the problem in an asymptotically optimal manner. Simulation results show that the proposed method can improve system performance significantly over the conventional methods.
Distributed Role Selection With ANC and TDBC Protocols in Two-Way Relaying Systems
Ding, Haiyang
2015-09-28
This paper advocates a distributed role selection strategy to coordinate two-way relaying transmissions among three cooperative nodes. For such, the local channel state information comparison and decision feedback mechanism are merged into classical analog network coding (ANC) and time division broadcast (TDBC) protocols such that the cooperative role of each node can be designated in a distributed fashion. We refer to this distributed role selection rule as d-ROSE. In both ANC-based and TDBC-based two-way relaying scenarios, strict proof for the equivalence of d-ROSE and optimal ROSE is given, which indicates that albeit the different form, their final role decision is essentially the same. Outage analysis for the d-ROSE strategy is carried out and the scaling law of the system outage behavior at high signal-to-noise ratio (SNR) is characterized, which manifests that d-ROSE can enhance the system diversity gain to one-order higher relative to the ANC and TDBC protocols. It is also shown that d-ROSE can reduce the signaling overhead upto 60% to perform the outage-optimal role selection. Finally, the impacts of node placement on the outage performance as well as the average signaling overhead of d-ROSE are numerically evaluated and some useful conclusions are drawn. © 2015 IEEE.
A score test for the agronomical overlap effect in a two-way classification model
Aquiles Darghan
2014-12-01
Full Text Available In some agricultural research, a treatment applied to an experimental unit may affect the response in the neighboring experimental units. This phenomenon is known as overlap. In this article, a test to evaluate this effect in the Draper and Guttman model was developed by imposing side conditions on the parameters of a two-way classification model to obtain a re-parameterized model which can be used in different neighboring patterns of experimental units, usually plants within a crop, whenever the nearest neighbor is considered a directly affected experimental unit and the two-way model is used. Three methods, namely maximum likelihood, least squares with side conditions and generalized inverse, were used to estimate the parameters of the original model in order to calculate the value of the test statistics for the null hypothesis associated with the absence of the overlapping effect. The three alternatives were invariant with respect to the use of test. The proposed test is simple to adopt and can be implemented in agronomy since its asymptotic nature is in agreement with the large number of experimental units which generally exist in this type of research, where each plant represents the experimental unit being assessed.
Multiple phase screen calculation of two-way spherical wave propagation in the ionosphere
Knepp, Dennis L.
2016-04-01
This paper presents a numerical solution to the parabolic wave equation for spherical wave propagation in a disturbed ionosphere. The solution uses the Fourier/split step approach where the propagation medium is modeled using multiple phase-changing screens separated by free space. The phase screens can consist of deterministic or random components describing spatial scales of any size. This solution consists of realizations of the signal (i.e., the ionospheric transfer function) after two-way propagation from a transmitter, through the medium to a target, and back. The transmitter and target can be comprised of multiple, independent point scatterers. The solution is applicable to many propagation problems including synthetic aperture radar and is not subject to the small-scene limitation, where all scatterers in the scene experience identical propagation conditions. Several examples are given illustrating some features of the solution including reciprocity, relationship between one- and two-way (monostatic and bistatic) scintillation index, and reflection from a large target.
Two-Way Optical Frequency Comparisons Over 100km Telecommunication Network Fibers
Bercy, Anthony; Lopez, Olivier; Chardonnet, Christian; Pottie, Paul-Eric; Amy-Klein, Anne
2014-01-01
By using two-way frequency transfer, we demonstrate ultra-high resolution comparison of optical frequencies over a telecommunication fiber link of 100 km operating simultaneously digital data transfer. We first propose and experiment a bi-directional scheme using a single fiber. We show that the relative stability at 1 s integration time is 7 10^18 and scales down to 5 10^21. The same level of performance is reached when an optical link is implemented with an active compensation of the fiber noise. We also implement a real-time two-way frequency comparison over a uni-directional telecommunication network using a pair of parallel fibers. The relative frequency stability is 10^15 at 1 s integration time and reaches 2 10^17 at 40 000 s. The fractional uncertainty of the frequency comparisons was evaluated for the best case to 2 10^20. These results open the way to accurate and high resolution frequency comparison of optical clocks over intercontinental fiber networks.
Prospective Teachers’ Semiotic Conflicts in Computing Probabilities from a Two-Way Table
Carmen Batanero
2015-04-01
Full Text Available The aim of this research was to assess the common knowledge of elementary probability in a sample of 183 prospective primary school teachers using and open-ended task, where teachers had to compute simple, compound and conditional probability from data presented in a two-way table. We base on theoretical ideas from the onto-semiotic approach to perform a semiotic analysis, in which we describe the mathematical objects and processes involved in the solutions of the tasks. Participants in the sample showed a weak common knowledge to compute simple, compound and conditional probabilities from a two-way table: they confused simple, compound and conditional probability; exchanged condition and event in conditional probabilities; confused probability and frequency or the union of events with the intersection. The semiotic analysis is used to provide and explanation for these errors in terms of semiotic conflicts. This list of difficulties expands what was found in previous research and may be used to reinforcing the preparation of prospective teachers to teach probability.
Two-Way Bending Properties of Shape Memory Composite with SMA and SMP
Hisaaki Tobushi
2009-09-01
Full Text Available A shape memory composite (SMC was fabricated with a shape memory alloy (SMA and a shape memory polymer (SMP, and its two-way bending deformation and recovery force were investigated. The results obtained can be summarized as follows: (1 two kinds of SMA tapes which show the shape memory effect (SME and superelasticity (SE were heat-treated to memorize the round shape. The shape-memorized round SMA tapes were arranged facing in the opposite directions and were sandwiched between the SMP sheets. The SMC belt can be fabricated by using the appropriate factors: the number of SMP sheets, the pressing force, the heating temperature and the hold time. (2 The twoway bending deformation with an angle of 56 degrees in the fabricated SMC belt is observed based on the SME and SE of the SMA tapes during heating and cooling. (3 If the SMC belt is heated and cooled by keeping the bent form, the recovery force increases during heating and degreases during cooling based on the two-way properties of the SMC. (4 The development and application of high-functional SMCs are expected by the combination of the SMA and the SMP with various kinds of phase transformation temperatures, volume fractions, configurations and heating-cooling rates.
Joint Network Coding and Opportunistic Transmission for Two-Way Relay Fading Channels
Liu, Jianquan; Xu, Youyun
2011-01-01
We investigate a two-way relay (TWR) fading channel where two source nodes wish to exchange information with the help of a relay node. The capacity of two-way relaying is known to be limited by the hop with weak channel condition due to immediate forwarding. In this paper, we introduce store-andforward (SF) relay protocol and present a joint network coding and opportunistic transmission (NCOT) for TWR channel. Through the use of NCOT method, a new upper bound on the ergodic sum-capacity for the TWR fading system is derived when delay tends to infinity. We further propose two alternative awaiting and broadcast (AAB) schemes: pure partial decoding (PPD) with SF-I and combinatorial decoding (CBD) with SF-II, which approach the new upper bound at high SNR with unbounded and bounded delay respectively. Numerical results show that the proposed AAB schemes significantly outperform the traditional physical layer network coding (PLNC) methods without delay. Compared to the traditional TWR schemes without delay, the pr...
Distributed cognitive two-way relay beamformer designs under perfect and imperfect CSI
Pandarakkottilil, Ubaidulla
2011-09-01
In this paper, we present distributed two-way relay beamformer designs for a cognitive radio network (CRN) in which a pair of cognitive (or secondary) transceiver nodes communicate with each other assisted by a set of cognitive two-way relay nodes. The secondary nodes share the spectrum with a licensed primary user (PU) node, and each node is assumed to be equipped with a single transmit/receive antenna. The interference to the PU resulting from the transmission from the cognitive nodes is kept below a specified limit. First, we consider relay beamformer designs assuming the availability of perfect channel state information (CSI). For this case, a mean-square error (MSE)-constrained beamformer that minimizes the total relay transmit power, and an MSE-balancing beamformer with a constraint on the total relay transmit power are proposed. Next, we consider relay beamformer designs assuming that the available CSI is imperfect. For this case too, we consider the same problems as those in the case of perfect CSI, and propose beamformer designs that are robust to the errors in the CSI. We show that the proposed designs can be reformulated as convex optimization problems that can be solved efficiently. Through numerical simulations, we illustrate the performance of the proposed designs. © 2011 IEEE.
Effect of width and boundary conditions on meeting maneuvers on two-way separated cycle tracks.
Garcia, Alfredo; Gomez, Fernando Agustin; Llorca, Carlos; Angel-Domenech, Antonio
2015-05-01
Cycle track design guidelines are rarely based on scientific studies. In the case of off-road two-way cycle tracks, a minimum width must facilitate both passing and meeting maneuvers, being meeting maneuvers the most frequent. This study developed a methodology to observe meeting maneuvers using an instrumented bicycle, equipped with video cameras, a GPS tracker, laser rangefinders and speed sensors. This bicycle collected data on six two-way cycle tracks ranging 1.3-2.15m width delimitated by different boundary conditions. The meeting maneuvers between the instrumented bicycle and every oncoming bicycle were characterized by the meeting clearance between the two bicycles, the speed of opposing bicycle and the reaction of the opposing rider: change in trajectory, stop pedaling or braking. The results showed that meeting clearance increased with the cycle track width and decreased if the cycle track had lateral obstacles, especially if they were higher than the bicycle handlebar. The speed of opposing bicycle shown the same tendency, although were more disperse. Opposing cyclists performed more reaction maneuvers on narrower cycle tracks and on cycle tracks with lateral obstacles to the handlebar height. Conclusions suggested avoiding cycle tracks narrower than 1.6m, as they present lower meeting clearances, lower bicycle speeds and frequent reaction maneuvers.
Two-Way Training Design for Discriminatory Channel Estimation in Wireless MIMO Systems
Huang, Chao-Wei
2011-01-01
This work examines the use of two-way training in multiple-input multiple-output (MIMO) wireless systems to discriminate the channel estimation performances between a legitimate receiver (LR) and an unauthorized receiver (UR). This thesis extends upon the previously proposed discriminatory channel estimation (DCE) scheme that allows only the transmitter to send training signals. The goal of DCE is to minimize the channel estimation error at LR while requiring the channel estimation error at UR to remain beyond a certain level. If the training signal is sent only by the transmitter, the performance discrimination between LR and UR will be limited since the training signals help both receivers perform estimates of their downlink channels. In this work, we consider instead the two-way training methodology that allows both the transmitter and LR to send training signals. In this case, the training signal sent by LR helps the transmitter obtain knowledge of the transmitter-to-LR channel, but does not help UR estim...
Superimposed XOR: Approaching Capacity Bounds of the Two-Way Relay Channels
Liu, Jianquan; Xu, Youyun; Wang, Xiaodong
2010-01-01
In two-way relay channels, bitwise XOR and symbol-level superposition coding are two popular network-coding based relaying schemes. However, neither of them can approach the capacity bound when the channels in the broadcast phase are asymmetric. In this paper, we present a new physical layer network coding (PLNC) scheme, called \\emph{superimposed XOR}. The new scheme advances the existing schemes by specifically taking into account the channel asymmetry as well as information asymmetry in the broadcast phase. We obtain its achievable rate regions over Gaussian channels when integrated with two known time control protocols in two-way relaying. We also demonstrate their average maximum sum-rates and service delay performances over fading channels. Numerical results show that the proposed superimposed XOR achieves a larger rate region than both XOR and superposition and performs much better over fading channels. We further deduce the boundary of its achievable rate region of the broadcast phase in an explicit an...
Turbulent phase noise on asymmetric two-way ground-satellite coherent optical links
Robert, Clélia; Conan, Jean-Marc; Wolf, Peter
2015-10-01
Bidirectional ground-satellite laser links suffer from turbulence-induced scintillation and phase distortion. We study how turbulence impacts on coherent detection capacity and on the associated phase noise that restricts clock transfer precision. We evaluate the capacity to obtain a two-way cancellation of atmospheric effects despite the asymmetry between up and down link that limits the link reciprocity. For ground-satellite links, the asymmetry is induced by point-ahead angle and possibly the use, for the ground terminal, of different transceiver diameters, in reception and emission. The quantitative analysis is obtained thanks to refined end-to-end simulations under realistic turbulence and wind conditions as well as satellite cinematic. Simulations make use of the reciprocity principle to estimate both down and up link performance from wave-optics propagation of descending plane waves. These temporally resolved simulations allow characterising the coherent detection in terms of time series of heterodyne efficiency for different system parameters. We show Tip/Tilt correction on ground is mandatory at reception for the down link and as a pre-compensation of the up link. Good correlation between up and down phase noise is obtained even with asymmetric apertures of the ground transceiver and in spite of pointing ahead angle. The reduction to less than 1 rad2 of the two-way differential phase noise is very promising for clock transfer.
van Venrooij, Ger E. P. M.; van Melick, Harm H. E.; Eckhardt, Mardy D.; Boon, Tom A.
2008-01-01
OBJECTIVES To investigate the information of voiding data in relation to symptoms and well-being in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) and to compare this information with that of prostate volume (Vprostate), maximal free urinary flow rate (
Duffy, James B.
1993-12-01
The purpose of the Advanced Transportation System Study (ATSS) task area 1 study effort is to examine manned launch vehicle booster concepts and two-way cargo transfer and return vehicle concepts to determine which of the many proposed concepts best meets NASA's needs for two-way transportation to low earth orbit. The study identified specific configurations of the normally unmanned, expendable launch vehicles (such as the National Launch System family) necessary to fly manned payloads. These launch vehicle configurations were then analyzed to determine the integrated booster/spacecraft performance, operations, reliability, and cost characteristics for the payload delivery and return mission. Design impacts to the expendable launch vehicles which would be required to perform the manned payload delivery mission were also identified. These impacts included the implications of applying NASA's man-rating requirements, as well as any mission or payload unique impacts. The booster concepts evaluated included the National Launch System (NLS) family of expendable vehicles and several variations of the NLS reference configurations to deliver larger manned payload concepts (such as the crew logistics vehicle (CLV) proposed by NASA JSC). Advanced, clean sheet concepts such as an F-1A engine derived liquid rocket booster (LRB), the single stage to orbit rocket, and a NASP-derived aerospace plane were also included in the study effort. Existing expendable launch vehicles such as the Titan 4, Ariane 5, Energia, and Proton were also examined. Although several manned payload concepts were considered in the analyses, the reference manned payload was the NASA Langley Research Center's HL-20 version of the personnel launch system (PLS). A scaled up version of the PLS for combined crew/cargo delivery capability, the HL-42 configuration, was also included in the analyses of cargo transfer and return vehicle (CTRV) booster concepts. In addition to strictly manned payloads, two-way cargo
Two-way cooperative AF relaying in spectrum-sharing systems: Enhancing cell-edge performance
Xia, Minghua
2012-09-01
In this contribution, two-way cooperative amplify-and-forward (AF) relaying technique is integrated into spectrumsharing wireless systems to improve spectral efficiency of secondary users (SUs). In order to share the available spectrum resources originally dedicated to primary users (PUs), the transmit power of a SU is optimized with respect to the average tolerable interference power at primary receivers. By analyzing outage probability and achievable data rate at the base station and at a cell-edge SU, our results reveal that the uplink performance is dominated by the average tolerable interference power at primary receivers, while the downlink always behaves like conventional one-way AF relaying and its performance is dominated by the average signal-to-noise ratio (SNR). These important findings provide fresh perspectives for system designers to improve spectral efficiency of secondary users in next-generation broadband spectrum-sharing wireless systems. © 2012 IEEE.
PL/SQL and Bind Variable: the two ways to increase the efficiency of Network Databases
Hitesh KUMAR SHARMA
2011-12-01
Full Text Available Modern data analysis applications are driven by the Network databases. They are pushing traditional database and data warehousing technologies beyond their limits due to their massively increasing data volumes and demands for low latency. There are three major challenges in working with network databases: interoperability due to heterogeneous data repositories, proactively due to autonomy of data sources and high efficiency to meet the application demand. This paper provides the two ways to meet the third challenge of network databases. This goal can be achieved by network database administrator with the usage of PL/SQL blocks and bind variable. The paper will explain the effect of PL/SQL block and bind variable on Network database efficiency to meet the modern data analysis application demand.
Energy efficient design for MIMO two-way AF multiple relay networks
Alsharoa, Ahmad M.
2014-04-01
This paper studies the energy efficient transmission and the power allocation problem for multiple two-way relay networks equipped with multi-input multi-output antennas where each relay employs an amplify-and-forward strategy. The goal is to minimize the total power consumption without degrading the quality of service of the terminals. In our analysis, we start by deriving closed-form expressions of the optimal powers allocated to terminals. We then employ a strong optimization tool based on the particle swarm optimization technique to find the optimal power allocated at each relay antenna. Our numerical results illustrate the performance of the proposed scheme and show that it achieves a sub-optimal solution very close to the optimal one.
Generalized F test and generalized deviance test in two-way ANOVA models for randomized trials.
Shen, Juan; He, Xuming
2014-01-01
We consider the problem of detecting treatment effects in a randomized trial in the presence of an additional covariate. By reexpressing a two-way analysis of variance (ANOVA) model in a logistic regression framework, we derive generalized F tests and generalized deviance tests, which provide better power in detecting common location-scale changes of treatment outcomes than the classical F test. The null distributions of the test statistics are independent of the nuisance parameters in the models, so the critical values can be easily determined by Monte Carlo methods. We use simulation studies to demonstrate how the proposed tests perform compared with the classical F test. We also use data from a clinical study to illustrate possible savings in sample sizes.
Outage Probability and Power Allocation for Two-Way DF Relay Networks with Relay Selection
Z. Fan
2012-09-01
Full Text Available In this paper, we investigate the outage probability and power allocation for the two-way decode-and-forward (DF relay networks with relay selection.~Specially, we consider independent but not necessarily identical distributed Rayleigh fading channels. Firstly, we derive an exact closed form outage probability expression. To shed light on the relation between the outage probability and the power allocation factor, an upper bound for the outage probability is derived, too. We then propose a power allocation scheme in the sense of minimizing this upper bound. Monte Carlo simulations are conducted to show that the derived outage probability expression excellently matches simulation results, and our proposed power allocation scheme performs effectively.
Beamforming in Two-Way Fixed Gain Amplify-and-Forward Relay Systems with CCI
Duong, Trung Q; Zepernick, Hans-Jurgen; Yuen, Chau
2012-01-01
We analyze the outage performance of a two-way fixed gain amplify-and-forward (AF) relay system with beamforming, arbitrary antenna correlation, and co-channel interference (CCI). Assuming CCI at the relay, we derive the exact individual user outage probability in closed-form. Additionally, while neglecting CCI, we also investigate the system outage probability of the considered network, which is declared if any of the two users is in transmission outage. Our results indicate that in this system, the position of the relay plays an important role in determining the user as well as the system outage probability via such parameters as signal-to-noise imbalance, antenna configuration, spatial correlation, and CCI power. To render further insights into the effect of antenna correlation and CCI on the diversity and array gains, an asymptotic expression which tightly converges to exact results is also derived.
Digital transceiver design for two-way AF-MIMO relay systems with imperfect CSI
Hu, Chia-Chang; Chou, Yu-Fei; Chen, Kui-He
2013-09-01
In the paper, combined optimization of the terminal precoders/equalizers and single-relay precoder is proposed for an amplify-and-forward (AF) multiple-input multiple-output (MIMO) two-way single-relay system with correlated channel uncertainties. Both terminal transceivers and relay precoding matrix are designed based on the minimum mean square error (MMSE) criterion when terminals are unable to erase completely self-interference due to imperfect correlated channel state information (CSI). This robust joint optimization problem of beamforming and precoding matrices under power constraints belongs to neither concave nor convex so that a nonlinear matrix-form conjugate gradient (MCG) algorithm is applied to explore local optimal solutions. Simulation results show that the robust transceiver design is able to overcome effectively the loss of bit-error-rate (BER) due to inclusion of correlated channel uncertainties and residual self-interference.
Performance analysis of two-way amplify and forward relaying with adaptive modulation
Hwang, Kyusung
2009-09-01
In this paper, we study two-way amplify-and-forward relaying in conjunction with adaptive modulation over a multiple relay network. In order to keep the diversity order equal to the number of relays and maintain a low complexity, we consider the best relay selection scheme in this work. Based on the proposed selection criterion for the best relay, we analyze the average spectral efficiency by its approximated upper bound. In addition, we extend the proposed scheme to the case where a direct path between source and destination exists. Our numerical examples show that the proposed system offers a considerable gain in the spectral efficiency while satisfying the error rates requirements. ©2009 IEEE.
A two-way nesting procedure for an ocean model with application to the Norwegian Sea
Heggelund, Yngve; Berntsen, Jarle
2000-11-01
Two-way nesting for a {sigma}-coordinate ocean model is implemented. The test case is a traveling low pressure along the west coast of Norway. Different methods for interaction between the coarse grid and the fine grid have been investigated. It is found that both a Dirichlet type and a FRS-type boundary condition for the fine grid give reasonable results for this test case. The FRS-type boundary condition gives a smoother transition between the coarse and fine grid, but more noise in the interior of the fine grid. With no feedback from the fine grid to the coarse grid, phase differences between the solutions on the two grids cause unphysical vortices to be found at the interface between the grids. (author)
A practical two-way system of quantum key distribution with untrusted source
Chen Ming-Juan; Liu Xiang
2011-01-01
The most severe problem of a two-way “plug-and-play” (p & p) quantum key distribution system is that the source can be controlled by the eavesdropper.This kind of source is defined as an “untrusted source”.This paper discusses the effects of the fluctuation of internal transmittance on the final key generation rate and the transmission distance.The security of the standard BB84 protocol,one-decoy state protocol,and weak+vacuum decoy state protocol,with untrusted sources and the fluctuation of internal transmittance are studied.It is shown that the one-decoy state is sensitive to the statistical fluctuation but weak+vacuum decoy state is only slightly affected by the fluctuation.It is also shown that both the maximum secure transmission distance and final key generation rate are reduced when Alice's laboratory transmittance fluctuation is considered.
On Achievable Rate Regions of the Asymmetric AWGN Two-Way Relay Channel
Ong, Lawrence; Johnson, Sarah J
2011-01-01
This paper investigates the additive white Gaussian noise two-way relay channel, where two users exchange messages through a relay. Asymmetrical channels are considered where the users can transmit data at different rates and at different power levels. We modify and improve existing coding schemes to obtain three new achievable rate regions. Comparing four downlink-optimal coding schemes, we show that the scheme that gives the best sum-rate performance is (i) complete-decode-forward, when both users transmit at low signal-to-noise ratio (SNR); (ii) functional-decode-forward with nested lattice codes, when both users transmit at high SNR; (iii) functional-decode-forward with rate splitting and time-division multiplexing, when one user transmits at low SNR and another user at medium--high SNR.
Alternative Awaiting and Broadcast for Two-Way Relay Fading Channels
Liu, Jianquan; Tao, Meixia
2011-01-01
We investigate a two-way relay (TWR) fading channel based on store-and-forward (SF), where two source nodes wish to exchange information with the help of a relay node. A new upper bound on the ergodic sum-capacity for the TWR fading system is derived when delay tends to infinity.We further propose two alternative awaiting and broadcast (AAB) schemes: pure partial decoding (PPD) with SF-I and combinatorial decoding (CBD) with SF-II, which approach the new upper bound at high SNR with unbounded and bounded delay respectively. Numerical results show that the proposed AAB schemes significantly outperform the traditional physical layer network coding (PLNC) methods without delay. Compared to the traditional TWR schemes without delay, the proposed CBD with SF-II method significantly improves the maximum sum-rate with an average delay of only some dozen seconds in the relay buffer.
Randomization for Security in Half-Duplex Two-Way Gaussian Channels
Gamal, Aly El; Gamal, Hesham El
2009-01-01
This paper develops a new physical layer framework for secure two-way wireless communication in the presence of a passive eavesdropper, i.e., Eve. Our approach achieves perfect information theoretic secrecy via a novel randomized scheduling and power allocation scheme. The key idea is to allow Alice and Bob to send symbols at random time instants. While Alice will be able to determine the symbols transmitted by Bob, Eve will suffer from ambiguity regarding the source of any particular symbol. This desirable ambiguity is enhanced, in our approach, by randomizing the transmit power level. Our theoretical analysis, in a 2-D geometry, reveals the ability of the proposed approach to achieve relatively high secure data rates under mild conditions on the spatial location of Eve. These theoretical claims are then validated by experimental results using IEEE 802.15.4-enabled sensor boards in different configurations, motivated by the spatial characteristics of Wireless Body Area Networks (WBAN).
Optimal relay selection and power allocation for cognitive two-way relaying networks
Pandarakkottilil, Ubaidulla
2012-06-01
In this paper, we present an optimal scheme for power allocation and relay selection in a cognitive radio network where a pair of cognitive (or secondary) transceiver nodes communicate with each other assisted by a set of cognitive two-way relays. The secondary nodes share the spectrum with a licensed primary user (PU), and each node is assumed to be equipped with a single transmit/receive antenna. The interference to the PU resulting from the transmission from the cognitive nodes is kept below a specified limit. We propose joint relay selection and optimal power allocation among the secondary user (SU) nodes achieving maximum throughput under transmit power and PU interference constraints. A closed-form solution for optimal allocation of transmit power among the SU transceivers and the SU relay is presented. Furthermore, numerical simulations and comparisons are presented to illustrate the performance of the proposed scheme. © 2012 IEEE.
VIDEO-BASED VEHICLE DETECTION ON A TWO-WAY ROAD
Zbigniew CZAPLA
2016-09-01
Full Text Available The paper presents a method of vehicle detection on a two-way road. Vehicle detection is carried out on the basis of the video stream from the camera placed over a road. The input image sequence is created by consecutive frames taken from the video stream. Images from the input image sequence are processed individually one by one. A detection field is defined for each lane of the road. Images from the input image sequence are converted into point image representation. The sums of the edge points within the detection fields are calculated. States of the detection fields are determined on the basis of calculated sums of the edge points. Vehicles are detected by analysis of states of the detection fields. Experimental results are provided.
Development of a Portable Two-Way Communication and Information Device for Deafblind People.
Ozioko, Oliver; Hersh, Marion
2015-01-01
This paper presents research on the development of a wearable two-way communication and information device for deafblind people who use tactile communications methods, namely the British deafblind manual alphabet and/or Braille. The device has two components: a glove worn by the deafblind person and a handheld display with keypad to be used by their hearing and sighted communication partner. Users can send messages using pressure sensors embedded in the glove and receive them by means of vibration on the palm. The two components are linked by Bluetooth and the use of Bluetooth to communicate with computers, mobile phones and other Bluetooth enabled devices is being investigated. The design was informed by feedback obtained from a survey of deafblind people and interviews with staff in two organisations for deafblind people. Research and development of the device is still ongoing.
Two-Way Selection for Growth Rate in the Common Carp (CYPRINUS CARPIO L.)
Moav, R.; Wohlfarth, G.
1976-01-01
The domesticated European carp was subjected to a two-way selection for growth rate. Five generations of mass selection for faster growth rate did not yield any response, but subsequent selection between groups (families) resulted in considerable progress while maintaining a large genetic variance. Selection for slow growth rate yielded relatively strong response for the first three generations. Random-bred control lines suffered from strong inbreeding depression and when two lines were crossed, the F1 showed a high degree of heterosis. Selection was performed on pond-raised fish, but growth rate was also tested in cages. A strong pond-cage genetic interaction was found. A theoretical explanation was suggested involving overdominance for fast growth rate and amplification through competition of intra-group but not inter-group variation. PMID:1248737
Two-way CSI-assisted AF relaying with HPA nonlinearity
Qi, Jian
2015-09-11
In this paper, we investigate half-duplex two-way dual-hop channel state information (CSI)-assisted amplify-andforward (AF) relaying in the presence of high-power amplifier (HPA) nonlinearity at relays. The expression for the end-toend signal-to-noise ratio (SNR) is derived as per the modified system model by taking into account the interference caused by relaying scheme and HPA nonlinearity. The system performance of the considered relaying network is evaluated in terms of average symbol error probability (SEP) in Nakagami-m fading channels, by making use of the moment-generating function (MGF) approach. Numerical results are provided and show the effects of several parameters, such as quadrature amplitude modulation (QAM) order, number of relays, HPA parameters, and Nakagami parameter, on performance. © 2015 IEEE.
Frequency transfer via a two-way optical phase comparison on a multiplexed fiber network.
Calosso, C E; Bertacco, E; Calonico, D; Clivati, C; Costanzo, G A; Frittelli, M; Levi, F; Mura, A; Godone, A
2014-03-01
We performed a two-way remote optical phase comparison on optical fiber. Two optical frequency signals were launched in opposite directions in an optical fiber and their phases were simultaneously measured at the other end. In this technique, the fiber noise is passively canceled, and we compared two optical frequencies at the ultimate 10(-21) stability level. The experiment was performed on a 47 km fiber that is part of the metropolitan network for Internet traffic. The technique relies on the synchronous measurement of the optical phases at the two ends of the link, which is here performed by digital electronics. This scheme offers some advantages with respect to active noise cancellation schemes, as the light travels only once in the fiber.
Outage Performance of Decode-and-Forward in Two-Way Relaying with Outdated CSI
Hyadi, Amal
2015-01-07
In this paper, we analyze the outage behavior of decode-and-forward relaying in the context of selective two-way cooperative systems. First, a new relay selection metric is proposed to take into consideration both transmission rates and instantaneous link conditions between cooperating nodes. Afterwards, the outage probability of the proposed system is derived for Nakagami-m fading channels in the case when perfect channel state information is available and then extended to the more realistic scenario where the available channel state information (CSI) is outdated due to fast fading. New expressions for the outage probability are obtained, and the impact of imperfect CSI on the performance is evaluated. Illustrative numerical results, Monte Carlo simulations, and comparisons with similar approaches are presented to assess the accuracy of our analytical derivations and confirm the performance gain of the proposed scheme.
Zhang, Chaobi; Chen, Jian Yun; Xu, Qiang; Li, Jing [School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian (China)
2015-08-15
In order to analyze the mechanical properties of two-way different configurations of prestressed concrete members subjected to axial loading, a finite element model based on the nuclear power plant containments is demonstrated. This model takes into account the influences of different principal stress directions, the uniaxial or biaxial loading, and biaxial loading ratio. The displacement-controlled load is applied to obtain the stress-strain response. The simulated results indicate that the differences of principal stress axes have great effects on the stress-strain response under uniaxial loading. When the specimens are subjected to biaxial loading, the change trend of stress with the increase of loading ratio is obviously different along different layout directions. In addition, correlation experiments and finite element analyses were conducted to verify the validity and reliability of the analysis in this study.
A Nonparametric Test of Interaction in the General Two-Way Layout
John ÖHRVIK
2010-01-01
Full Text Available The two-way layout is frequently occurring, e.g. blocking is used to reduce the between subject variability when comparing treatments or many medical centers are included in a clinical trial to recruit a sufficient number of patients. In epidemiological studies, it is common to study the interactions between genetic and environmental factors. This paper is concerned with the statistical analysis of data arising in these situations when assumptions like normality do not necessarily apply. The main objective of this paper is to propose a test for interactions for continuous data based on joint ranking of all observations after iteratively eliminating the two main effects. The validity of the significance levels of the test when using a finite sample version of the asymptotic distribution of the test statistic is manifested and the power against different alternatives illustrated by extensive simulation experiments. The proposed test is compared with competitors on published data sets. Data from the Survey of Adolescent Life in Vestmanland (SALVe project are analyzed both with our test and Brunner and Puri's proposal. The test shows good asymptotic and small sample properties. It can be used in the general two-way layout and multiple comparisons can be performed in a straightforward way. The analyses of the SALVe project show that our proposal can be useful in such studies. It has the potential to pick-up interactions hidden in the noise of gross errors when using standard ANOVA. The test may become a valuable tool and alternative to other proposals in exploring interactions.
Two-way coupled fluid structure interaction simulation of a propeller turbine
Schmucker, H [Voith Hydro GmbH and Co. KG, Germany Alexanderstrasse 11, 89522 Heidenheim (Germany); Flemming, F; Coulson, S, E-mail: Hannes.Schmucker@voith.co [Voith Hydro Inc. York, PA, 760 East Berlin Road, York, PA, 17408 (United States)
2010-08-15
During the operation of a hydro turbine the fluid mechanical pressure loading on the turbine blades provides the driving torque on the turbine shaft. This fluid loading results in a structural load on the component which in turn causes the turbine blade to deflect. Classically, these mechanical stresses and deflections are calculated by means of finite element analysis (FEA) which applies the pressure distribution on the blade surface calculated by computational fluid dynamics (CFD) as a major boundary condition. Such an approach can be seen as a oneway coupled simulation of the fluid structure interaction (FSI) problem. In this analysis the reverse influence of the deformation on the fluid is generally neglected. Especially in axial machines the blade deformation can result in a significant impact on the turbine performance. The present paper analyzes this influence by means of fully two-way coupled FSI simulations of a propeller turbine utilizing two different approaches. The configuration has been simulated by coupling the two commercial solvers ANSYS CFX for the fluid mechanical simulation with ANSYS Classic for the structure mechanical simulation. A detailed comparison of the results for various blade stiffness by means of changing Young's Modulus are presented. The influence of the blade deformation on the runner discharge and performance will be discussed and shows for the configuration investigated no significant influence under normal structural conditions. This study also highlights that a two-way coupled fluid structure interaction simulation of a real engineering configuration is still a challenging task for today's commercially available simulation tools.
Khe, A. K.; Cherevko, A. A.; Chupakhin, A. P.; Bobkova, M. S.; Krivoshapkin, A. L.; Orlov, K. Yu
2016-06-01
In this paper a computer simulation of a blood flow in cerebral vessels with a giant saccular aneurysm at the bifurcation of the basilar artery is performed. The modelling is based on patient-specific clinical data (both flow domain geometry and boundary conditions for the inlets and outlets). The hydrodynamic and mechanical parameters are calculated in the frameworks of three models: rigid-wall assumption, one-way FSI approach, and full (two-way) hydroelastic model. A comparison of the numerical solutions shows that mutual fluid- solid interaction can result in qualitative changes in the structure of the fluid flow. Other characteristics of the flow (pressure, stress, strain and displacement) qualitatively agree with each other in different approaches. However, the quantitative comparison shows that accounting for the flow-vessel interaction, in general, decreases the absolute values of these parameters. Solving of the hydroelasticity problem gives a more detailed solution at a cost of highly increased computational time.
Hao, Shijie; Liu, Yinong; Ren, Yang; Jiang, Daqiang; Yang, Feng; Cong, Daoyong; Wang, Yandong; Cui, Lishan
2016-06-08
Inspired by the driving principle of traditional bias-type two-way actuators, we developed a novel two-way actuation nanocomposite wire in which a massive number of Nb nanoribbons with ultra-large elastic strains are loaded inside a shape memory alloy (SMA) matrix to form a continuous array of nano bias actuation pairs for two-way actuation. The composite exhibits a two-way actuation strain of 3.2% during a thermal cycle and an actuation stress of 934 MPa upon heating, which is about twice higher than that (~500 MPa) found in reported two-way SMAs. Upon cooling, the composite shows an actuation stress of 134 MPa and a mechanical work output of 1.08*106 J/ m3, which are about three and five times higher than that of reported two-way SMAs, respectively. It is revealed that the massive number of Nb nanoribbons in compressive state provides the high actuation stress and high work output upon cooling and the SMA matrix with high yield strength offers the high actuation stress upon heating. Compared to traditional bias-type two-way actuators, the two-way actuation composite with small volume and simple construct is in favour of the miniaturization and simplification of actuators.
2013-04-11
... COMMISSION Certain Two-Way Global Satellite Communication Devices, System and Components Thereof Issuance of... importation, and the sale within the United States after importation of certain two-way global satellite communication devices, system and components thereof by reason of infringement of certain claims of U.S. Patent...
2012-08-23
... COMMISSION Certain Two-Way Global Satellite Communication Devices, System and Components Thereof; Notice of... Commission has received a complaint entitled Certain Two-Way Global Satellite Communication Devices, System... satellite communication devices, systems. The complaint names as respondents Delorme Publishing Company Inc...
Lopez, Lisa M.; Tapanes, Vanessa
2011-01-01
Research on two-way immersion programs has empirically investigated the success of such programs on children's dual-language development. The present study focuses on the language abilities of Latino children attending a Spanish-English differentiated two-way immersion program in the United States. Family dynamics relating to placement in this…
Block, Nicholas
2011-01-01
Forty initially English-dominant Latino students in four 90:10 Spanish two-way dual-immersion programs and 62 of their peers in mainstream English programs were studied to find out if their attitudes toward Spanish and Spanish-dominant individuals differ. Significant differences were found on many variables, with two-way dual-immersion students…
Hao, Shijie; Liu, Yinong; Ren, Yang; Jiang, Daqiang; Yang, Feng; Cong, Daoyong; Wang, Yandong; Cui, Lishan
2016-06-29
Inspired by the driving principle of traditional bias-type two-way actuators, we developed a novel two-way actuation nanocomposite wire in which a massive number of Nb nanoribbons with ultralarge elastic strains are loaded inside a shape memory alloy (SMA) matrix to form a continuous array of nanobias actuation pairs for two-way actuation. The composite exhibits a two-way actuation strain of 3.2% during a thermal cycle and an actuation stress of 934 MPa upon heating, which is about twice as high as that (∼500 MPa) found in reported two-way SMAs. Upon cooling, the composite shows an actuation stress of 134 MPa and a mechanical work output of 1.08 × 10(6) J/m(3), which are about three and five times higher than those of reported two-way SMAs, respectively. It was revealed that the massive number of Nb nanoribbons in the compressive state provides the high actuation stress and high work output upon cooling, and the SMA matrix with high yield strength offers the high actuation stress upon heating. Compared to traditional bias-type two-way actuators, the two-way actuation composite with a small volume and simple construct works well with the miniaturization and simplification of actuators.
Komovkin, S. V.; Lavrenov, S. M.; Tuchin, A. G.; Tuchin, D. A.; Yaroshevsky, V. S.
2016-12-01
The article describes a model of the two-way measurements of radial velocity based on the Doppler effect. The relations are presented for the instantaneous value of the increment range at the time of measurement and the radial velocity of the mid-dimensional interval. The compensation of methodological errors of interpretation of the two-way Doppler measurements is considered.
Redman-MacLaren Michelle
2012-12-01
Full Text Available Abstract Introduction Capacity building has been employed in international health and development sectors to describe the process of ‘experts’ from more resourced countries training people in less resourced countries. Hence the concept has an implicit power imbalance based on ‘expert’ knowledge. In 2011, a health research strengthening workshop was undertaken at Atoifi Adventist Hospital, Solomon Islands to further strengthen research skills of the Hospital and College of Nursing staff and East Kwaio community leaders through partnering in practical research projects. The workshop was based on participatory research frameworks underpinned by decolonising methodologies, which sought to challenge historical power imbalances and inequities. Our research question was, “Is research capacity strengthening a two-way process?” Methods In this qualitative study, five Solomon Islanders and five Australians each responded to four open-ended questions about their experience of the research capacity strengthening workshop and activities: five chose face to face interview, five chose to provide written responses. Written responses and interview transcripts were inductively analysed in NVivo 9. Results Six major themes emerged. These were: Respectful relationships; Increased knowledge and experience with research process; Participation at all stages in the research process; Contribution to public health action; Support and sustain research opportunities; and Managing challenges of capacity strengthening. All researchers identified benefits for themselves, their institution and/or community, regardless of their role or country of origin, indicating that the capacity strengthening had been a two-way process. Conclusions The flexible and responsive process we used to strengthen research capacity was identified as mutually beneficial. Using community-based participatory frameworks underpinned by decolonising methodologies is assisting to redress
Handa, Takemi; Orihashi, Kazumasa; Nishimori, Hideaki; Yamamoto, Masaki
2016-11-01
Maximal graft flow acceleration (max df/dt) determined using transit-time flowmetry (TTFM) in the diastolic phase was assessed as a potential predictor of graft failure for aortocoronary artery (AC) bypass grafts in coronary artery bypass patients. Max df/dt was retrospectively measured in 114 aortocoronary artery bypass grafts. TTFM data were fitted to a 9-polynomial curve, which was derived from the first-derivative curve, to measure max df/dt (9-polynomial max df/dt). Abnormal TTFM was defined as a mean flow of 5 or a diastolic filling ratio of polynomial max df/dt was significantly lower in abnormal TTFM/failing by the CAG group compared with abnormal TTFM/patent by the CAG group (1.08 ± 0.89 vs. 2.05 ± 1.51 ml/s(2), respectively; P polynomial max df/dt in the early diastolic phase may be a promising predictor of future graft failure for AC bypass grafts, particularly in abnormal TTFM grafts.
A Novel Secure Transmission Scheme in MIMO Two-Way Relay Channels with Physical Layer Approach
Qiao Liu
2017-01-01
Full Text Available Security issue has been considered as one of the most pivotal aspects for the fifth-generation mobile network (5G due to the increasing demands of security service as well as the growing occurrence of security threat. In this paper, instead of focusing on the security architecture in the upper layer, we investigate the secure transmission for a basic channel model in a heterogeneous network, that is, two-way relay channels. By exploiting the properties of the transmission medium in the physical layer, we propose a novel secure scheme for the aforementioned channel mode. With precoding design, the proposed scheme is able to achieve a high transmission efficiency as well as security. Two different approaches have been introduced: information theoretical approach and physical layer encryption approach. We show that our scheme is secure under three different adversarial models: (1 untrusted relay attack model, (2 trusted relay with eavesdropper attack model, and (3 untrusted relay with eavesdroppers attack model. We also derive the secrecy capacity of the two different approaches under the three attacks. Finally, we conduct three simulations of our proposed scheme. The simulation results agree with the theoretical analysis illustrating that our proposed scheme could achieve a better performance than the existing schemes.
Multi-pair cognitive two-way relaying and power allocation under imperfect CSI
Pandarakkottilil, Ubaidulla
2013-06-01
In this paper, we present a robust joint relay precoder design and transceiver power allocation for a cognitive radio network under imperfect channel state information. The secondary (or cognitive) network consists of multiple pairs of single-antenna transceiver nodes and a non-regenerative two-way relay with multiple antennas which aids the intra-pair communication process of the transceiver nodes. The secondary nodes share the spectrum with a licensed primary user (PU) while guaranteeing that the interference to the PU receiver is maintained below a specified threshold. The proposed robust design is based on the minimization of the sum mean-square error (MSE) of the transceiver nodes under constraints on the secondary users\\' transmit powers and interference to PU the receiver. Though the original problem is non-convex, we show that the proposed design can be solved using alternating optimization of convex subproblems which have analytic or efficient numerical solutions. We illustrate the performance of the proposed designs through some selected numerical simulations. © 2013 IEEE.
Two-way self-consistent coupling of HEIDI in SWMF
Ilie, R.; Liemohn, M. W.; Toth, G.
2013-12-01
In this study we present results from the two-way coupling between the kinetic Hot Electron and Ion Drift Integrator (HEIDI) model and the Space Weather Modeling Framework (SWMF). HEIDI solves the time dependent, gyration and bounced averaged kinetic equation for the phase space density of different ring current species and computes full pitch angle distributions for all local times and radial distances. This model was generalized to accommodate an arbitrary magnetic field and, through the coupling with SWMF, it obtains the magnetic field description along with the plasma distribution at the model boundaries from the Block Adaptive Tree Solar Wind Roe Upwind Scheme (BATS-R-US) magnetohydrodynamics (MHD) model within the SWMF. Electric field self-consistency is assured by the passing of convection potentials from the Ridley Ionosphere Model (RIM) within SWMF. Our study tests the various levels of coupling between the 3 models, highlighting the roles that the magnetic field, plasma sheet conditions and the cross polar cap potential play in the formation and evolution of the ring current. The results of the self-consistent coupling between HEIDI, BATSRUS and RIM during disturbed conditions emphasize the importance of a kinetic self-consistent approach to the description of the geospace.
EEG/MEG Source Reconstruction with Spatial-Temporal Two-Way Regularized Regression
Tian, Tian Siva
2013-07-11
In this work, we propose a spatial-temporal two-way regularized regression method for reconstructing neural source signals from EEG/MEG time course measurements. The proposed method estimates the dipole locations and amplitudes simultaneously through minimizing a single penalized least squares criterion. The novelty of our methodology is the simultaneous consideration of three desirable properties of the reconstructed source signals, that is, spatial focality, spatial smoothness, and temporal smoothness. The desirable properties are achieved by using three separate penalty functions in the penalized regression framework. Specifically, we impose a roughness penalty in the temporal domain for temporal smoothness, and a sparsity-inducing penalty and a graph Laplacian penalty in the spatial domain for spatial focality and smoothness. We develop a computational efficient multilevel block coordinate descent algorithm to implement the method. Using a simulation study with several settings of different spatial complexity and two real MEG examples, we show that the proposed method outperforms existing methods that use only a subset of the three penalty functions. © 2013 Springer Science+Business Media New York.
Joint Source and Relay Precoding Designs for MIMO Two-Way Relaying Based on MSE Criterion
Wang, Rui
2011-01-01
Properly designed precoders can significantly improve the spectral efficiency of multiple-input multiple-output (MIMO) relay systems. In this paper, we investigate joint source and relay precoding design based on the mean-square-error (MSE) criterion in MIMO two-way relay systems, where two multi-antenna source nodes exchange information via a multi-antenna amplify-and-forward relay node. This problem is non-convex and its optimal solution remains unsolved. Aiming to find an efficient way to solve the problem, we first decouple the primal problem into three tractable sub-problems, and then propose an iterative precoding design algorithm based on alternating optimization. The solution to each sub-problem is optimal and unique, thus the convergence of the iterative algorithm is guaranteed. Secondly, we propose a structured precoding design to lower the computational complexity. The proposed precoding structure is able to parallelize the channels in the multiple access (MAC) phase and broadcast (BC) phase. It th...
Pairwise Check Decoding for LDPC Coded Two-Way Relay Block Fading Channels
Liu, Jianquan; Xu, Youyun
2011-01-01
Partial decoding is known to have the potential to achieve a larger rate region than that of full decoding in two-way relay (TWR) channels. Existing partial decoding realizations are however designed for Gaussian channels and with a static physical layer network coding (PLNC) mapping. In this paper, we propose a new channel coding solution at the relay, called \\emph{pairwise check decoding} (PCD), for low-density parity-check (LDPC) coded TWR system over block fading channels. The main idea is to form a check relationship table (check-relation-tab) for the superimposed LDPC coded packet pair in the multiple access (MA) phase in conjunction with an adaptive PLNC mapping in the broadcast (BC) phase. Using PCD, we then present a partial decoding method, two-stage closest-neighbor clustering with PCD (TS-CNC-PCD), with the aim of minimizing the worst pairwise error performance. Moreover, a kind of correlative rows optimization, named as the minimum correlation optimization (MCO), is proposed for selecting the bet...
Source-receiver two-way wave extrapolation for prestack exploding-reflector modelling and migration
Alkhalifah, Tariq Ali
2014-10-08
Most modern seismic imaging methods separate input data into parts (shot gathers). We develop a formulation that is able to incorporate all available data at once while numerically propagating the recorded multidimensional wavefield forward or backward in time. This approach has the potential for generating accurate images free of artiefacts associated with conventional approaches. We derive novel high-order partial differential equations in the source-receiver time domain. The fourth-order nature of the extrapolation in time leads to four solutions, two of which correspond to the incoming and outgoing P-waves and reduce to the zero-offset exploding-reflector solutions when the source coincides with the receiver. A challenge for implementing two-way time extrapolation is an essential singularity for horizontally travelling waves. This singularity can be avoided by limiting the range of wavenumbers treated in a spectral-based extrapolation. Using spectral methods based on the low-rank approximation of the propagation symbol, we extrapolate only the desired solutions in an accurate and efficient manner with reduced dispersion artiefacts. Applications to synthetic data demonstrate the accuracy of the new prestack modelling and migration approach.
Two-way shape memory behavior of semi-crystalline elastomer under stress-free condition
Qian, Chen; Dong, Yubing; Zhu, Yaofeng; Fu, Yaqin
2016-08-01
Semi-crystalline shape memory polymers exhibit two-way shape memory effect (2W-SME) under constant stresses through crystallization-induced elongation upon cooling and melting-induced constriction upon heating. The applied constant stress influenced the prediction and usability of 2W-SME in practical applications without any external force. Here the reversible shape transition in EVA-shaped memory polymer was quantitative analyzed under a suitable temperature range and external stress-free condition. The fraction of reversible strain increased with increasing upper temperature (T high) within the temperature range and reached the maximum value of 13.62% at 70 °C. However, reversible strain transition was almost lost when T high exceeded 80 °C because of complete melting of crystalline scaffold, known as the latent recrystallization template. The non-isothermal annealing of EVA 2W-SMP under changing circulating temperatures was confirmed. Moreover, the orientation of crystallization was retained at high temperatures. These findings may contribute to design an appropriate shape memory protocol based on application-specific requirements.
Gaussian Two-way Relay Channel with Private Information for the Relay
Ho, Chin Keong; Sun, Sumei
2011-01-01
We introduce a generalized two-way relay channel where two sources exchange information (not necessarily of the same rate) with help from a relay, and each source additionally sends private information to the relay. We consider the Gaussian setting where all point-to-point links are Gaussian channels. For this channel, we consider a two-phase protocol consisting of a multiple access channel (MAC) phase and a broadcast channel (BC) phase. We propose a general decode-and-forward (DF) scheme where the MAC phase is related to computation over MAC, while the BC phase is related to BC with receiver side information. In the MAC phase, we time share a capacity-achieving code for the MAC and a superposition code with a lattice code as its component code. We show that the proposed DF scheme is near optimal for any channel conditions, in that it achieves rates within half bit of the capacity region of the two-phase protocol.
Performance Analysis of Adaptive Physical Layer Network Coding for Wireless Two-way Relaying
Muralidharan, Vijayvaradharaj T
2012-01-01
The analysis of modulation schemes for the physical layer network-coded two way relaying scenario is presented which employs two phases: Multiple access (MA) phase and Broadcast (BC) phase. It was shown by Koike-Akino et. al. that adaptively changing the network coding map used at the relay according to the channel conditions greatly reduces the impact of multiple access interference which occurs at the relay during the MA phase. Depending on the signal set used at the end nodes, deep fades occur for a finite number of channel fade states referred as the singular fade states. The singular fade states fall into the following two classes: The ones which are caused due to channel outage and whose harmful effect cannot be mitigated by adaptive network coding are referred as the \\textit{non-removable singular fade states}. The ones which occur due to the choice of the signal set and whose harmful effects can be removed by a proper choice of the adaptive network coding map are referred as the \\textit{removable} sin...
Carrier-phase Two-Way Satellite Frequency Transfer over a Very Long Baseline
Fujieda, M; Gotoh, T; Becker, J; Aida, M; Bauch, A
2014-01-01
In this paper we report that carrier-phase two-way satellite time and frequency transfer (TWSTFT) was successfully demonstrated over a very long baseline of 9,000 km, established between the National Institute of Information and Communications Technology (NICT) and the Physikalisch-Technische Bundesanstalt (PTB). We verified that the carrier-phase TWSTFT (TWCP) result agreed with those obtained by conventional TWSTFT and GPS carrier-phase (GPSCP) techniques. Moreover, a much improved short-term instability for frequency transfer of $2\\times10^{-13}$ at 1 s was achieved, which is at the same level as previously confirmed over a shorter baseline within Japan. The precision achieved was so high that the effects of ionospheric delay became significant which are ignored in conventional TWSTFT even over a long link. We compensated for these effects using ionospheric delays computed from regional vertical total electron content maps. The agreement between the TWCP and GPSCP results was improved because of this compe...
Artificial muscles made of chiral two-way shape memory polymer fibers
Yang, Qianxi; Fan, Jizhou; Li, Guoqiang
2016-10-01
In this work, we demonstrate the unusual improvement of the tensile actuation of hierarchically chiral structured artificial muscle made of two-way shape memory polymer (2W-SMP) fiber. Experimental results show that the chemically cross-linked poly(ethylene-co-vinyl acetate) 2W-SMP fibers possess an average negative coefficient of thermal expansion (NCTE) that is at least one order higher than that of the polyethylene fiber used previously. As expected, the increase in axial thermal contraction of the precursor fiber leads to an increase in the recovered torque ( 4.4 Nmm ) of the chiral fiber and eventually in the tensile actuation of the twisted-then-coiled artificial muscle ( 67.81 ±1.82 % ). A mechanical model based on Castigliano's second theorem is proposed, and the calculated result is consistent with the experimental result (64.17% tensile stroke). The model proves the significance of the NCTE and the recovered torque on tensile actuation of the artificial muscle and can be used as a guidance for the future design.
Usefulness of phage typing and "two-way ribotyping" to differentiate Salmonella enteritidis strains.
Landeras, E; Usera, M A; Calderón, C; Mendoza, M C
1997-12-01
The capacity to differentiate Salmonella enteritidis strains by phage typing and "two-way ribotyping" performed with PstI and SphI was evaluated. The typeability was 96.8% in phage typing and 100% in ribotyping. The series was differentiated into 13 phage types, 19 combined ribotypes, and 39 subtypes or clonal lines by combining results from both methods (of which 11, 13, and 35, respectively, were represented by natural strains). Ribotyping differentiated strains ascribed to PTs 1, 4, 6a, 7, 8, RDNC and UPT. Conversely, some strains of PTs 1, 4, 5a, 6, 6a, 7, 34, RDNC and UPT fall into the most frequent combined ribotype. A dendrogram of genetic similarity generated from the combined ribotypes was traced, and, at a 0.82 similarity level, it showed a major cluster (including 17 combined ribotypes, 88.4% strains ascribed to all PTs tested except PT11), a minor cluster, and four additional lines more loosely related.
Robust distributed two-way relay beamforming in cognitive radio networks
Pandarakkottilil, Ubaidulla
2012-04-01
In this paper, we present distributed beamformer designs for a cognitive radio network (CRN) consisting of a pair of cognitive (or secondary) transceiver nodes communicating with each other through a set of secondary non-regenerative two-way relays. The secondary network shares the spectrum with a licensed primary user (PU), and operates under a constraint on the maximum interference to the PU, in addition to its own resource and quality of service (QoS) constraints. We propose beamformer designs assuming that the available channel state information (CSI) is imperfect, which reflects realistic scenarios. The performance of proposed designs is robust to the CSI errors. Such robustness is critical in CRNs given the difficulty in acquiring perfect CSI due to loose cooperation between the PUs and the secondary users (SUs), and the need for strict enforcement of PU interference limit. We consider a mean-square error (MSE)-constrained beamformer that minimizes the total relay transmit power and an MSE-balancing beamformer with a constraint on the total relay transmit power. We show that the proposed designs can be reformulated as convex optimization problems that can be solved efficiently. Through numerical simulations, we illustrate the improved performance of the proposed robust designs compared to non-robust designs. © 2012 IEEE.
Effective Two-way Communication of Environmental Hazards: Understanding Public Perception in the UK
Lorono-Leturiondo, Maria; O'Hare, Paul; Cook, Simon; Hoon, Stephen R.; Illingworth, Sam
2017-04-01
Climate change intensified hazards, such as floods and landslides, require exploring renewed ways of protecting at-risk communities (World Economic Forum 2016). Scientists are being encouraged to explore new pathways to work closely with affected communities in search of experiential knowledge that is able to complement and extend scientific knowledge (see for instance Whatmore and Landström 2011 and Höpner et al. 2010). Effective two-way communication of environmental hazards is, however, a challenge. Besides considering factors such as the purpose of communication, or the characteristics of the different formats; effective communication has to carefully acknowledge the personal framework of the individuals involved. Existing experiences, values, beliefs, and needs are critical determinants of the way they perceive and relate to these hazards, and in turn, of the communication process in which they are involved (Longnecker 2016 and Gibson et al. 2016). Our study builds on the need to analyze how the public perceives environmental hazards in order to establish forms of communication that work. Here we present early findings of a survey analysing the UK public's perception and outline how survey results can guide more effective two-way communication practices between scientists and affected communities. We explore the perception of environmental hazards in terms of how informed and concerned the public is, as well as how much ownership they claim over these phenomena. In order to gain a more accurate image, we study environmental hazards in relation to other risks threatening the UK, such as large-scale involuntary migration or unemployment (World Economic Forum 2016, Bord et al. 1998). We also explore information consumption in relation to environmental hazards and the public's involvement in advancing knowledge. All these questions are accompanied by an extensive demographics section that allows us to ascertain how the context or environment in which an
Two-way WKB Approximation Applied to GPR - COST Action TU1208
Prokopovich, Igor; Popov, Alexei; Marciniak, Marian; Pajewski, Lara
2016-04-01
The main goal of subsurface radio wave probing consists in reconstruction of the shape and the electrical properties of buried objects in material media. For this purpose the knowledge of the laws of EM pulse excitation and propagation in non-uniform subsurface medium is required, as well as the methods and algorithms of solving the inverse problem. Two ways of treating this problem exist. On the one hand, one can describe EM wave propagation by solving the Maxwell's equations with finite difference methods implemented in computer codes. However, when solving inverse problems, pure numerical algorithms require huge amount of calculation and, as a consequence, long calculation time. In this respect, more promising are analytical approaches. Here, we apply couple wave theory ("two-way WKB" approximation) to the problem of subsurface wave propagation. The derived formulas can be used in GPR design and for fast data processing of the experimental data. We start from the 1D model problem of GPR probing. Classical WKB method [1] allows one to describe wave propagation through non-uniform media with slowly varying dielectric permittivity. A principal shortcoming of this approximation is that it does not take into account backward reflection from permittivity gradients. Consequently, WKB method as such can not be used for the purposes of GPR sounding. An extension of this approximation consists in solving two coupled WKB-type equations by iterations. This approach properly describes backward reflections and provides good accuracy in a wide frequency range [2]. In our previous work [3] a time-domain counterpart of the Bremmer-Brekhovkikh approximation has been derived and applied to a 1D inverse problem of subsurface medium probing by an ultra-wide band EM pulse. In order to convert this approach into a practical GPR algorithm, a more realistic model is required: 2D or 3D propagation from a localized source with the effects of wave divergence and refraction taken into
Wang, Jia; Bast, Tobias; Wang, Yu-Cong; Zhang, Wei-Ning
2015-12-01
Hippocampal lesions tend to facilitate two-way active avoidance (2WAA) conditioning, where rats learn to cross to the opposite side of a conditioning chamber to avoid a tone-signaled footshock. This classical finding has been suggested to reflect that hippocampus-dependent place/context memory inhibits 2WAA (a crossing response to the opposite side is inhibited by the memory that this is the place where a shock was received on the previous trial). However, more recent research suggests other aspects of hippocampal function that may support 2WAA learning. More specifically, the ventral hippocampus has been shown to contribute to behavioral responses to aversive stimuli and to positively modulate the meso-accumbens dopamine system, whose activation has been implicated in 2WAA learning. Permanent hippocampal lesions may not reveal these contributions because, following complete and permanent loss of hippocampal output, other brain regions may mediate these processes or because deficits could be masked by lesion-induced extra-hippocampal changes, including an upregulation of accumbal dopamine transmission. Here, we re-examined the hippocampal role in 2WAA learning in Wistar rats, using permanent NMDA-induced neurotoxic lesions and temporary functional inhibition by muscimol or tetrodotoxin (TTX) infusion. Complete hippocampal lesions tended to facilitate 2WAA learning, whereas ventral (VH) or dorsal hippocampal (DH) lesions had no effect. In contrast, VH or DH muscimol or TTX infusions impaired 2WAA learning. Ventral infusions caused an immediate impairment, whereas after dorsal infusions rats showed intact 2WAA learning for 40-50 min, before a marked deficit emerged. These data show that functional inhibition of ventral hippocampus disrupts 2WAA learning, while the delayed impairment following dorsal infusions may reflect the time required for drug diffusion to ventral hippocampus. Overall, using temporary functional inhibition, our study shows that the ventral
Two-Way Radio Modem Data Transfer for Newborn Hearing Screening Devices.
Matulat, Peter; Lepper, Ingo; Böttcher, Peter; Parfitt, Ross; Oswald, Hans; Am Zehnhoff-Dinnesen, Antoinette; Deuster, Dirk
2017-01-01
The success of a newborn hearing screening program depends on successful tracking and follow-up to ensure that children who have had positive screening results in the first few days of life receive appropriate and timely diagnostic and intervention services. The easy availability, through a suitable infrastructure, of the data necessary for the tracking, diagnosis, and care of children concerned is a major key to enhancing the quality and efficiency of newborn hearing screening programs. Two systems for the automated two-way transmission of newborn hearing screening and configuration data, based on mobile communication technology, for the screening devices MADSEN AccuScreen(®) and Natus Echo-Screen(®) were developed and tested in a field study. Radio modem connections were compared with conventional analogue modem transmissions from Natus Echo-Screen devices for duration, transmission rate, number of lost connections, and frequency of use. The average session duration was significantly lower with the MADSEN AccuScreen (12 s) and Natus Echo-Screen both with radio modem (15 s) than the Natus Echo-Screen with analogue modem (108 s). The transmission rate was significantly higher (898 and 1,758 vs. 181 bytes/s) for the devices with radio modems. Both radio modem devices had significantly lower rates of broken connections after initial connection (2.1 and 0.9 vs. 5.5%). An increase in the frequency of data transmission from the clinics with mobile radio devices was found. The use of mobile communication technology in newborn hearing screening devices offers improvements in the average session duration, transmission rate, and reliability of the connection over analogue solutions. We observed a behavioral change in clinical staff using the new technology: the data exchange with the tracking center is more often used. The requirements for on-site support were reduced. These savings outweigh the small increase in costs for the Internet service provider.
Joint Preprocesser-Based Detectors for One-Way and Two-Way Cooperative Communication Networks
Abuzaid, Abdulrahman I.
2014-05-01
Efficient receiver designs for cooperative communication networks are becoming increasingly important. In previous work, cooperative networks communicated with the use of L relays. As the receiver is constrained, channel shortening and reduced-rank techniques were employed to design the preprocessing matrix that reduces the length of the received vector from L to U. In the first part of the work, a receiver structure is proposed which combines our proposed threshold selection criteria with the joint iterative optimization (JIO) algorithm that is based on the mean square error (MSE). Our receiver assists in determining the optimal U. Furthermore, this receiver provides the freedom to choose U for each frame depending on the tolerable difference allowed for MSE. Our study and simulation results show that by choosing an appropriate threshold, it is possible to gain in terms of complexity savings while having no or minimal effect on the BER performance of the system. Furthermore, the effect of channel estimation on the performance of the cooperative system is investigated. In the second part of the work, a joint preprocessor-based detector for cooperative communication networks is proposed for one-way and two-way relaying. This joint preprocessor-based detector operates on the principles of minimizing the symbol error rate (SER) instead of minimizing MSE. For a realistic assessment, pilot symbols are used to estimate the channel. From our simulations, it can be observed that our proposed detector achieves the same SER performance as that of the maximum likelihood (ML) detector with all participating relays. Additionally, our detector outperforms selection combining (SC), channel shortening (CS) scheme and reduced-rank techniques when using the same U. Finally, our proposed scheme has the lowest computational complexity.
This study evaluates interior nudging techniques using the Weather Research and Forecasting (WRF) model for regional climate modeling over the conterminous United States (CONUS) using a two-way nested configuration. NCEP–Department of Energy Atmospheric Model Intercomparison Pro...
SOME ASPECTS OF THE TWO WAY SHAPE MEMORY EFFECT INDUCED BY PSEUDOELASTIC CYCLING IN Cu-Zn-Al ALLOYS
Cesari, E.; Picornell, C.; Pons, J.; Sade, M.
1991-01-01
The two-way shape memory effect (TWSME) induced by pseudoelastic cycling in Cu-Zn-Al single crystals has been studied. We analyzed the influence of the mechanical cycling characteristics (tensile or compressing) and of the presence of [MATH]-phase precipitates in the material. The two-way memory effect induced by compressing cycling appears after a smaller number of cycles than in tensile pseudoelastic cycling. The presence of [MATH]-phase precipitates also reduces the number of cycles needed...
Two Way Coupling RAM-SCB to the Space Weather Modeling Framework
Welling, D. T.; Jordanova, V. K.; Zaharia, S. G.; Toth, G.
2010-12-01
The Ring current Atmosphere interaction Model with Self-Consistently calculated 3D Magnetic field (RAM-SCB) has been used to successfully study inner magnetosphere dynamics during different solar wind and magnetosphere conditions. Recently, one way coupling of RAM-SCB with the Space Weather Modeling Framework (SWMF) has been achieved to replace all data or empirical inputs with those obtained through first-principles-based codes: magnetic field and plasma flux outer boundary conditions are provided by the Block Adaptive Tree Solar wind Roe-type Upwind Scheme (BATS-R-US) MHD code, convection electric field is provided by the Ridley Ionosphere Model (RIM), and ion composition is provided by the Polar Wind Outflow Model (PWOM) combined with a multi-species MHD approach. These advances, though creating a powerful inner magnetosphere virtual laboratory, neglect the important mechanisms through which the ring current feeds back into the whole system, primarily the stretching of the magnetic field lines and shielding of the convection electric field through strong region two Field Aligned Currents (FACs). In turn, changing the magnetosphere in this way changes the evolution of the ring current. To address this shortcoming, the coupling has been expanded to include feedback from RAM-SCB to the other coupled codes: region two FACs are returned to the RIM while total plasma pressure is used to nudge the MHD solution towards the RAM-SCB values. The impacts of the two way coupling are evaluated on three levels: the global magnetospheric level, focusing on the impact on the ionosphere and the shape of the magnetosphere, the regional level, examining the impact on the development of the ring current in terms of energy density, anisotropy, and plasma distribution, and the local level to compare the new results to in-situ measurements of magnetic and electric field and plasma. The results will also be compared to past simulations using the one way coupling and no coupling
Weerts, David J.; Sandman, Lorilee R.
2008-01-01
Recent reforms in the Carnegie Foundation classification system and regional accreditation standards have fueled momentum for community engagement in higher education. This study employs a knowledge-flow conceptual framework to identify barriers and facilitators that influence the adoption of an engagement agenda at land-grant and urban research…
Profit maximization mitigates competition
Dierker, Egbert; Grodal, Birgit
1996-01-01
We consider oligopolistic markets in which the notion of shareholders' utility is well-defined and compare the Bertrand-Nash equilibria in case of utility maximization with those under the usual profit maximization hypothesis. Our main result states that profit maximization leads to less price...... competition than utility maximization. Since profit maximization tends to raise prices, it may be regarded as beneficial for the owners as a whole. Moreover, if profit maximization is a good proxy for utility maximization, then there is no need for a general equilibrium analysis that takes the distribution...... of profits among consumers fully into account and partial equilibrium analysis suffices...
Handa, Takemi; Orihashi, Kazumasa; Nishimori, Hideaki; Fukutomi, Takashi; Yamamoto, Masaki; Kondo, Nobuo; Tashiro, Miwa
2015-04-01
Maximal graft flow acceleration (max df/dt) determined by transit-time flowmetry (TTFM) in the diastolic phase was assessed as a possible predictor of graft failure in coronary artery bypass patients. Max df/dt was retrospectively measured in 57 in situ left internal thoracic artery grafts. TTFM data were fitted to a 5-polynomial curve, which was derived from the first-derivative curve to measure max df/dt (5-polymial max df/dt). Abnormal TTFM was defined as a mean flow of 5 or diastolic filling ratio of polynomial max df/dt between each group pair (P polynomial max df/dt was significantly lower in the Ab-N/F group compared with the other groups (Ab-N/F: 0.89 ± 0.41 vs N/P: 4.74 ± 3.18, N/F: 2.23 ± 0.65, Ab-N/P: 2.70 ± 1.31 ml/s(2), P polynomial max df/dt were, respectively, 72.7 and 80.4% (cut-off value, 1.918 ml/s(2)) for all grafts and 100 and 88.2% (cut-off value, 1.273 ml/s(2)) for abnormal TTFM grafts. The TTFM 5-polymial max df/dt value in the early diastolic phase may be a promising predictor of future graft failure. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
Optimal link removal for epidemic mitigation: a two-way partitioning approach.
Enns, Eva A; Mounzer, Jeffrey J; Brandeau, Margaret L
2012-02-01
The structure of the contact network through which a disease spreads may influence the optimal use of resources for epidemic control. In this work, we explore how to minimize the spread of infection via quarantining with limited resources. In particular, we examine which links should be removed from the contact network, given a constraint on the number of removable links, such that the number of nodes which are no longer at risk for infection is maximized. We show how this problem can be posed as a non-convex quadratically constrained quadratic program (QCQP), and we use this formulation to derive a link removal algorithm. The performance of our QCQP-based algorithm is validated on small Erdős-Renyi and small-world random graphs, and then tested on larger, more realistic networks, including a real-world network of injection drug use. We show that our approach achieves near optimal performance and out-performs other intuitive link removal algorithms, such as removing links in order of edge centrality.
A Research on Errors in Two-way Satellite Time and Frequency Transfer
Wu, W. J.
2013-07-01
The two-way satellite time and frequency transfer (TWSTFT) is one of the most accurate means for remote clock comparison with an uncertainty in time of less than 1 ns and with a relative uncertainty in frequency of about 10^{-14} d^{-1}. The transmission paths of signals between two stations are almost symmetrical in the TWSTFT. In principal, most of all kinds of path delays are canceled out, which guarantees the high accuracy of TWSTFT. With the development of TWSTFT and the increase in the frequence of observations, it is showed that the diurnal variation of systematic errors is about 1˜3 ns in the TWSTFT. This problem has become a hot topic of research around the world. By using the data of Transfer Satellite Orbit Determination Net (TSODN) and international TWSTFT links, the systematic errors are studied in detail as follows: (1) The atmospheric effect. This includes ionospheric and tropospheric effects. The tropospheric effect is very small, and it can be ignored. The ionospheric error can be corrected by using the IGS ionosphere product. The variations of ionospheric effect are about 0˜0.05 ns and 0˜0.7 ns at KU band and C band, respectively, and have the diurnal variation characteristics. (2) The equipment time delay. The equipment delay is closely related with temperature, presenting a linear relation at the normal temperature. Its outdoor part indicates the characteristics of the diurnal variation with the environment temperature. The various kinds of effects related with the modem are studied. Some resolutions are proposed. (3) The satellite transponder effect. This effect is studied by using the data of international TWSTFT links. It is analyzed that different satellite transponders can highly increase the amplitude of the diurnal variation in one TWSTFT link. This is the major reason of the diurnal variation in the TWSTFT. The function fitting method is used to basically solve this problem. (4) The satellite motion effect. The geostationary
High-Efficiency Ka-Band Waveguide Two-Way Asymmetric Power Combiner
Wintucky, E. G.; Simons, R. N.; Freeman, J. C.; Chevalier, C. T.
2011-01-01
NASA is planning a number of Space Exploration, Earth Observation and Space Science missions where Ka-band solid-state power amplifiers (SSPAs) could have a role. Monolithic microwave integrated circuit (MMIC) based SSPAs with output powers on the order of 10 W at Ka-band frequencies would be adequate to satisfy the data transmission rate requirements at the distances involved. MMICs are a type of integrated circuit fabricated on a GaAs wafer, which operates at micro wave frequencies and performs the function of signal amplification. The highest power Ka-band (31.8 to 32.3 GHz) SSPA to have flown in space had an output power of 2.6 W with an overall efficiency of 14.3 percent. This SSPA was built around discrete GaAs pHEMT (high electron mobility transistor) devices and flew aboard the Deep Space One spacecraft. State-of-the-art GaAs pHEMT-based MMIC power amplifiers (PAs) can deliver RF power at Ka-band frequencies anywhere from 3 W with a power added efficiency (PAE) of 32 percent to 6 W with a PAE of 26 percent. However, to achieve power levels higher than 6 W, the output of several MMIC PAs would need to be combined using a high-efficiency power combiner. Conventional binary waveguide power combiners, based on short-slot and magic-T circuits, require MMIC PAs with identical amplitude and phase characteristics for high combining efficiency. However, due to manufacturing process variations, the output powers of the MMIC PAs tend to be unequal, and hence the need to develop unequal power combiners. A two-way asymmetric magic-T based power combiner for MMIC power amplifiers, which can take in unequal inputs, has been successfully designed, fabricated, and characterized over NASA s Deep Space Network (DSN) frequency range of 31.8 to 32.3 GHz. The figure is a transparent view of the a sym - metric combiner that shows the 4-port configuration and the internal structure. The rod, post, and iris are positioned by design to achieve the desired asymmetric power ratio
Nam, Jahyun; Kang, Chiho; Song, Jeongyong; Jang, Gunhee
2017-05-01
We compared one-way and two-way coupled analyses of electromagnetic machines considering magnetic and structural interaction to identify the frequency components of magnetic excitation and to determine the structural coupling effects predicted only by the two-way coupled analysis. We developed finite element models of a C-core switch and an electric motor. In the two-way coupled analysis method, the magnetic force calculated by using the Maxwell stress tensor was applied to the structural finite element model to determine the elastic deformation, and the magnetic finite element model was rearranged by means of the moving mesh method to represent the structural elastic deformation. We showed that two-way coupled analysis predicted the excitation frequency of 80 Hz (4 times the input current frequency) of magnetic force in the C-core switch and the excitation frequency of 667 Hz (the first natural frequency of the rotor, corresponding to the translational mode) of magnetic force in the electric motor undergoing rotor eccentricity. We showed that two-way coupled analysis predicted magnetic excitation and its corresponding structural response more accurately than the one-way coupled analysis, especially for electromagnetic machines in which the structural deformation affects magnetic field through variation of the air gap length.
Two-way shape memory effect and its stability in Ti-Ni-Hf high temperature shape memory alloy
MENG Xiang-long; WU Ye; CAI Wei; ZHAO Lian-cheng
2005-01-01
The two-way shape memory effect (TWSME) in a Ti36 Ni49 Hf15 high temperature shape memory alloy (SMA) was systematically studied by bending tests. In the TiNiHf alloy, the martensite deformation is an effective method to get two-way shape memory effect even with a small deformation strain. The results indicate that the internal stress field formed by the bending deformation is in the direction of the preferentially oriented martensite variants formed during the bending deformation. Upon cooling the preferentially oriented martensite variants form under such an oriented stress field, which should be responsible for the generation of the two-way shape memory effect.Proper training process benefits the formation of the oriented stress field, resulting in the improvement of the twoway shape memory effect. A maximum TWSME of 0.88 % is obtained in the present alloy.
Perkins, Jeff; Sponholz, R. O.
1984-02-01
The character and mechanism of two-way shape memory in Cu-Zn-Al alloys is investigated by means of closely controlled thermomechanical cycling and careful measurement of the progressive effect of the particular “training” routine, as well as by correlary studies of submicrostructural evolution as training proceeds. The results establish the quantitative relationship between the cyclic training routine and the ability of the sample to exhibit two-way shape memory. The variation of numerous training parameters with cycling is presented and interpreted. Microscopic studies indicate that as two-way shape memory training proceeds, specific physical features develop in the parent phase submicrostructure, particularly dislocation tangles and “vestigial” martensite markings; these assist in the nucleation and growth of a preferred martensite plate arrangement during cooling.
Maximally incompatible quantum observables
Heinosaari, Teiko, E-mail: teiko.heinosaari@utu.fi [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Schultz, Jussi, E-mail: jussi.schultz@gmail.com [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Toigo, Alessandro, E-mail: alessandro.toigo@polimi.it [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy); Ziman, Mario, E-mail: ziman@savba.sk [RCQI, Institute of Physics, Slovak Academy of Sciences, Dúbravská cesta 9, 84511 Bratislava (Slovakia); Faculty of Informatics, Masaryk University, Botanická 68a, 60200 Brno (Czech Republic)
2014-05-01
The existence of maximally incompatible quantum observables in the sense of a minimal joint measurability region is investigated. Employing the universal quantum cloning device it is argued that only infinite dimensional quantum systems can accommodate maximal incompatibility. It is then shown that two of the most common pairs of complementary observables (position and momentum; number and phase) are maximally incompatible.
Lambrechts, Michiel; Capelo, Holly L; Blum, Jürgen; Bodenschatz, Eberhard
2016-01-01
The behaviour of sedimenting particles depends on the dust-to-gas ratio of the fluid. Linear stability analysis shows that solids settling in the Epstein drag regime would remain homogeneously distributed in non-rotating incompressible fluids, even when dust-to-gas ratios reach unity. However, the non-linear evolution has not been probed before. Here, we present numerical calculations indicating that in a particle-dense mixture solids spontaneously mix out of the fluid and form swarms overdense in particles by at least a factor 10. The instability is caused by mass-loaded regions locally breaking the equilibrium background stratification. The driving mechanism depends on non-linear perturbations of the background flow and shares some similarity to the streaming instability in accretion discs. The resulting particle-rich swarms may stimulate particle growth by coagulation. In the context of protoplanetary discs, the instability could be relevant for aiding small particles to settle to the midplane in the outer...
Costa, F T M; Avril, M; Nogueira, P A; Gysin, J
2006-12-01
Malaria is undoubtedly the world's most devastating parasitic disease, affecting 300 to 500 million people every year. Some cases of Plasmodium falciparum infection progress to the deadly forms of the disease responsible for 1 to 3 million deaths annually. P. falciparum-infected erythrocytes adhere to host receptors in the deep microvasculature of several organs. The cytoadhesion of infected erythrocytes to placental syncytiotrophoblast receptors leads to pregnancy-associated malaria (PAM). This specific maternal-fetal syndrome causes maternal anemia, low birth weight and the death of 62,000 to 363,000 infants per year in sub-Saharan Africa, and thus has a poor outcome for both mother and fetus. However, PAM and non-PAM parasites have been shown to differ antigenically and genetically. After multiple pregnancies, women from different geographical areas develop adhesion-blocking antibodies that protect against placental parasitemia and clinical symptoms of PAM. The recent description of a new parasite ligand encoded by the var2CSA gene as the only gene up-regulated in PAM parasites renders the development of an anti-PAM vaccine more feasible. The search for a vaccine to prevent P. falciparum sequestration in the placenta by eliciting adhesion-blocking antibodies and a cellular immune response, and the development of new methods for evaluating such antibodies should be key priorities in mother-child health programs in areas of endemic malaria. This review summarizes the main molecular, immunological and physiopathological aspects of PAM, including findings related to new targets in the P. falciparum var gene family. Finally, we focus on a new methodology for mimicking cytoadhesion under blood flow conditions in human placental tissue.
F.T.M. Costa
2006-12-01
Full Text Available Malaria is undoubtedly the world's most devastating parasitic disease, affecting 300 to 500 million people every year. Some cases of Plasmodium falciparum infection progress to the deadly forms of the disease responsible for 1 to 3 million deaths annually. P. falciparum-infected erythrocytes adhere to host receptors in the deep microvasculature of several organs. The cytoadhesion of infected erythrocytes to placental syncytiotrophoblast receptors leads to pregnancy-associated malaria (PAM. This specific maternal-fetal syndrome causes maternal anemia, low birth weight and the death of 62,000 to 363,000 infants per year in sub-Saharan Africa, and thus has a poor outcome for both mother and fetus. However, PAM and non-PAM parasites have been shown to differ antigenically and genetically. After multiple pregnancies, women from different geographical areas develop adhesion-blocking antibodies that protect against placental parasitemia and clinical symptoms of PAM. The recent description of a new parasite ligand encoded by the var2CSA gene as the only gene up-regulated in PAM parasites renders the development of an anti-PAM vaccine more feasible. The search for a vaccine to prevent P. falciparum sequestration in the placenta by eliciting adhesion-blocking antibodies and a cellular immune response, and the development of new methods for evaluating such antibodies should be key priorities in mother-child health programs in areas of endemic malaria. This review summarizes the main molecular, immunological and physiopathological aspects of PAM, including findings related to new targets in the P. falciparum var gene family. Finally, we focus on a new methodology for mimicking cytoadhesion under blood flow conditions in human placental tissue.
Two-Way Integration of WRF and CCSM for Regional Climate Simulations
Lin, Wuyin [Brookhaven National Laboratory; Zhang, Minghua [Stony Brook University; He, Juanxiong [Stony Brook University; Jiao, Xiangmin [Stony Brook University; Chen, Ying [Stony Brook University; Colle, Brian [Stony Brook University; Vogelmann, Andrew M. [Brookhaven National Laboratory; Liu, Ping [Stony Brook University; Khairoutdinov, Marat [Stony Brook University; Leung, Ruby [Pacific Northwest National Laboratory
2013-07-12
Under the support of the DOE award DE-SC0004670, we have successfully developed an integrated climate modeling system by nesting Weather Research and Forecasting (WRF) model within the Community Climate System Model (CCSM) and the ensuing new generation Community Earth System Model (CESM). The integrated WRF/CESM system is intended as one method of global climate modeling with regional simulation capabilities. It allows interactive dynamical regional downscaling in the computational flow of present or future global climate simulations. This capability substantially simplifies the process of dynamical downscaling by avoiding massive intermediate model outputs at high frequency that are typically required for offline regional downscaling. The inline coupling also has the advantage of higher temporal resolution for the interaction between regional and global model components. With the aid of the inline coupling, a capability has also been developed to ingest other global climate simulations (by CESM or other models), which otherwise may not have necessary intermediate outputs for regional downscaling, to realize their embedded regional details. It is accomplished by relaxing the global atmospheric state of the integrated model to that of the source simulations with an appropriate time scale. This capability has the potential to open a new venue for ensemble regional climate simulations using a single modeling system. Furthermore, this new modeling system provides an effective modeling framework for the studies of physical and dynamical feedbacks of regional weather phenomena to the large scale circulation. The projected uses of this capability include the research of up-scaling effect of regional weather system, and its use as an alternative physical representation of sub-scale processes in coarser-resolution climate models.
Camminatiello, Ida; D'Ambra, Antonello; Sarnacchiaro, Pasquale
2014-01-01
In this paper we are proposing a general framework for the analysis of the complete set of log Odds Ratios (ORs) generated by a two-way contingency table. Starting from the RC (M) association model and hypothesizing a Poisson distribution for the counts of the two-way contingency table we are obtaining the weighted Log Ratio Analysis that we are extending to the study of log ORs. Particularly we are obtaining an indirect representation of the log ORs and some synthesis measures. Then for studying the matrix of log ORs we are performing a generalized Singular Value Decomposition that allows us to obtain a direct representation of log ORs. We also expect to get summary measures of association too. We have considered the matrix of complete set of ORs, because, it is linked to the two-way contingency table in terms of variance and it allows us to represent all the ORs on a factorial plan. Finally, a two-way contingency table, which crosses pollution of the Sarno river and sampling points, is to be analyzed to illustrate the proposed framework.
Meaning Making and Translanguaging in a Two-Way Dual-Language Program on the U.S.-Mexico Border
Esquinca, Alberto; Araujo, Blanca; de la Piedra, María Teresa
2014-01-01
The article analyzes meaning-making practices in a two-way dual-language (TWDL) program on the U.S.-Mexico border among "transfronterizo" and Mexican-origin youth. In the article, we show that emergent bilingual learners and their teacher participate in activities that mediate understanding of science content knowledge. We show how the…
Vera, J. Fernando; Macias, Rodrigo; Heiser, Willem J.
2009-01-01
In this paper, we propose a cluster-MDS model for two-way one-mode continuous rating dissimilarity data. The model aims at partitioning the objects into classes and simultaneously representing the cluster centers in a low-dimensional space. Under the normal distribution assumption, a latent class model is developed in terms of the set of…
2010-04-01
... hazards evaluation and classification —Language of communication and transmission of information 2. Crisis Management System —Crisis analysis and communication mechanisms —Establishment of contact points —Reporting... Considered in Developing a Two-Way Alert System 1. Documentation —Definition of a crisis/emergency and...
Li, Jennifer; Steele, Jennifer; Slater, Robert; Bacon, Michael; Miller, Trey
2016-01-01
Many educators and policy makers look to two-way dual language immersion as one of the most promising options to close achievement gaps for English learners. However, the programs' effectiveness depends on the quality of their implementation. This article reports on a large-scale study of the implementation of dual language immersion across a…
Li, Jennifer J.; Steele, Jennifer L.; Slater, Robert; Bacon, Michael; Miller, Trey
2016-01-01
Dual-language immersion programs--in which students learn core subjects (language arts, math, science, and social studies) in both English and a "partner" language--have been gaining in popularity across the United States. Such programs may use a "two-way model," in which roughly half the students are native speakers of the…
Li, Jennifer; Steele, Jennifer; Slater, Robert; Bacon, Michael; Miller, Trey
2016-01-01
Many educators and policy makers look to two-way dual language immersion as one of the most promising options to close achievement gaps for English learners. However, the programs' effectiveness depends on the quality of their implementation. This article reports on a large-scale study of the implementation of dual language immersion across a…
Head-on crashes on two-way interurban roads: a public health concern in road safety
Marta Olabarria
2015-09-01
Conclusions: This study allowed the characterization of crashes and drivers involved in head-on crashes on two-way interurban roads. The lower probability observed on roads with median strips point to these measures as an effective way to reduce these collisions
Moments Based Framework for Performance Analysis of One-Way/Two-Way CSI-Assisted AF Relaying
Xia, Minghua
2012-09-01
When analyzing system performance of conventional one-way relaying or advanced two-way relaying, these two techniques are always dealt with separately and, thus, their performance cannot be compared efficiently. Moreover, for ease of mathematical tractability, channels considered in such studies are generally assumed to be subject to Rayleigh fading or to be Nakagami-$m$ channels with integer fading parameters, which is impractical in typical urban environments. In this paper, we propose a unified moments-based framework for general performance analysis of channel-state-information (CSI) assisted amplify-and-forward (AF) relaying systems. The framework is applicable to both one-way and two-way relaying over arbitrary Nakagami-$m$ fading channels, and it includes previously reported results as special cases. Specifically, the mathematical framework is firstly developed under the umbrella of the weighted harmonic mean of two Gamma-distributed variables in conjunction with the theory of Pad\\\\\\'e approximants. Then, general expressions for the received signal-to-noise ratios of the users in one-way/two-way relaying systems and the corresponding moments, moment generation function, and cumulative density function are established. Subsequently, the mathematical framework is applied to analyze, compare, and gain insights into system performance of one-way and two-way relaying techniques, in terms of outage probability, average symbol error probability, and achievable data rate. All analytical results are corroborated by simulation results as well as previously reported results whenever available, and they are shown to be efficient tools to evaluate and compare system performance of one-way and two-way relaying.
Parker, Andrew M.; Wandi Bruine de Bruin; Baruch Fischhoff
2007-01-01
Our previous research suggests that people reporting a stronger desire to maximize obtain worse life outcomes (Bruine de Bruin et al., 2007). Here, we examine whether this finding may be explained by the decision-making styles of self-reported maximizers. Expanding on Schwartz et al. (2002), we find that self-reported maximizers are more likely to show problematic decision-making styles, as evidenced by self-reports of less behavioral coping, greater dependence on others when making decisions...
Impact of I/Q imbalance on the performance of two-way CSI-assisted AF relaying
Qi, Jian
2013-04-01
In this paper, we investigate half-duplex two-way dual-hop channel state information (CSI)-assisted amplify-and-forward (AF) relaying in the presence of in-phase and quadrature-phase (I/Q) imbalance. A compensation approach for the I/Q imbalance is proposed, which employs the received signals together with their conjugations to detect the desired signal. We also derive the average symbol error probability of the considered half-duplex two-way dual-hop CSI-assisted AF relaying networks with and without compensation for I/Q imbalance in Rayleigh fading channels. Numerical results are provided and show that the proposed compensation method mitigates the impact of I/Q imbalance to a certain extent. © 2013 IEEE.
Quantum hacking of two-way continuous-variable quantum key distribution using Trojan-horse attack
Ma, Hong-Xin; Bao, Wan-Su; Li, Hong-Wei; Chou, Chun
2016-08-01
We present a Trojan-horse attack on the practical two-way continuous-variable quantum key distribution system. Our attack mainly focuses on the imperfection of the practical system that the modulator has a redundancy of modulation pulse-width, which leaves a loophole for the eavesdropper inserting a Trojan-horse pulse. Utilizing the unique characteristics of two-way continuous-variable quantum key distribution that Alice only takes modulation operation on the received mode without any measurement, this attack allows the eavesdropper to render all of the final keys shared between the legitimate parties insecure without being detected. After analyzing the feasibility of the attack, the corresponding countermeasures are put forward. Project supported by the National Basic Research Program of China (Grant No. 2013CB338002) and the National Natural Science Foundation of China (Grant Nos. 11304397 and 61505261).
Tests of additivity in mixed and fixed effect two-way ANOVA models with single sub-class numbers
Rasch, Dieter; Rusch, Thomas; Simeckova, Marie; Kubinger, Klaus D.; Moder, Karl; Simecek, Petr
2009-01-01
In variety testing as well as in psychological assessment, the situation occurs that in a two-way ANOVA-type model with only one replication per cell, analysis is done under the assumption of no interaction between the two factors. Tests for this situation are known only for fixed factors and normally distributed outcomes. In the following we will present five additivity tests and apply them to fixed and mixed models and to quantitative as well as to Bernoulli distributed data....
Two- way Shape Memory Effect in a Ti-Ni-Nb Shape Memory Alloy with Wide Hysteresis
无
2001-01-01
A two-way shape memory effect (TWSME) in the Ti46.3Ni44.7Nb9 alloy has been systematically investigated by means of bending test and transmission electron microscopy (TEM) observations. Based on the analysis of the microstructure after training, the mechanism of TWSME in the Ti46.3Ni44.7Nb9 alloy has been discussed.
Lu, Yao; Harrington, Peter B
2007-09-01
With respect to the emerging role of forensic science for arson investigation, a low cost and promising onsite detection method for ignitable liquids is desirable. Gas chromatography-differential mobility spectrometry (GC-DMS) was investigated as a tool for analysis of ignitable liquids from fire debris. Headspace solid-phase microextraction (SPME) was applied as the preconcentration and sampling method. The combined information afforded by gas chromatography and differential mobility spectrometry provided unique two-way patterns for each sample of ignitable liquid. Two-way GC-DMS data were classified into one of seven ignitable liquids using a fuzzy rule-building expert system (FuRES). The performance of the classifier was validated using bootstrap Latin partitions (BLPs) and also compared to optimized partial least-squares (PLS) classifiers. Better prediction results can be obtained by using two-way GC-DMS data than only using one-way total ion chromatograms or integrated differential mobility spectra. FuRES models constructed with the neat ignitable liquids identified the spiked samples from simulated fire debris with 99.07 +/- 0.04% accuracy.
Robert, Clélia; Conan, Jean-Marc; Wolf, Peter
2016-03-01
Bidirectional ground-satellite laser links suffer from turbulence-induced scintillation and phase distortion. We study the impact of turbulence on coherent detection and the related phase noise that restricts time and frequency transfer precision. We evaluate the capacity to obtain a two-way cancellation of atmospheric effects despite the asymmetry between up- and downlink that limits the link reciprocity. For ground-satellite links, the asymmetry is induced by point-ahead angle and possibly the use, for the ground terminal, of different transceiver diameters, in reception and emission. The quantitative analysis is obtained thanks to refined end-to-end simulations under realistic turbulence and wind conditions as well as satellite kinematics. These temporally resolved simulations allow characterizing the coherent detection in terms of time series of heterodyne efficiency and phase noise for different system parameters. We show that tip-tilt correction on ground is mandatory at reception for the downlink and as a pre-compensation of the uplink. Besides, thanks to the large tilt angular correlation, the correction is shown to be efficient on uplink despite the point-ahead angle. Very good two-way compensation of turbulent effects is obtained even with the asymmetries. The two-way differential phase noise is reduced to 1 rad2 , with the best fractional frequency stability below 2 ×10-17 after 1-s averaging time.
无
2011-01-01
The 19th World Congress of the International Federation of Translators (FIT) was held in San Francisco from August 1-4.Huang Youyi,Vice President of China International Publishing Group,has just completed a term as FIT vice president.At the conference site on August 1,Huang talked to Beijing Review on his role in the FIT,as well as the development of the language service industry in China.
Black, Mabel
1975-01-01
The development of adult programs of family life education in Ohio from the 1930s to the present is recounted. Approximately half the article describes a series of 12 half-hour television programs which present family life education in a soap opera format, and the research from which it was developed. (AJ)
Atherton, David
When I first started working as a Voluntary Service Overseas (VSO) nurse lecturer in Malawi, where the focus of health care is often a lack of resources and staff shortages, I realised how important it was for care to be apparent in every patient encounter.
Cody, Anthony
2013-01-01
One popular approach to teacher leadership is to identify certain teachers as particularly successful, then have others learn from them. Collaborative leadership, in contrast, looks at leadership as a quality that anyone can have. In this model, the goal is not to figure out who is best. Instead, teachers share their unique talents and interests…
Cody, Anthony
2013-01-01
One popular approach to teacher leadership is to identify certain teachers as particularly successful, then have others learn from them. Collaborative leadership, in contrast, looks at leadership as a quality that anyone can have. In this model, the goal is not to figure out who is best. Instead, teachers share their unique talents and interests…
Schuster, Mareike; Thürkow, Markus; Weiher, Stefan; Kirchner, Ingo; Ulbrich, Uwe; Will, Andreas
2016-04-01
A general bias of global atmosphere ocean models, and also of the MPI-ESM, is an under-representation of the high latitude cyclone activity and an overestimation of the mid latitude cyclone activity in the North Atlantic, thus representing the extra-tropical storm track too zonal. We will show, that this effect can be antagonized by applying an atmospheric Two-Way Coupling (TWC). In this study we present a newly developed Two-Way Coupled model system, which is based on the MPI-ESM, and show that it is able to capture the mean storm track location more accurate. It also influences the sub-decadal deterministic predictability of extra-tropical cyclones and shows significantly enhanced skill compared to the "uncoupled" MPI-ESM standalone system. This study evaluates a set of hindcast experiments performed with said Two-Way Coupled model system. The regional model COSMO CLM is Two-Way Coupled to the atmosphere of the global Max-Plack-Institute Earth System Model (MPI-ESM) and therefore integrates and exchanges the state of the atmosphere every 10 minutes (MPI-TWC-ESM). In the coupled source region (North Atlantic), mesoscale processes which are relevant for the formation and early-stage development of cyclones are expected to be better represented, and therefore influence the large scale dynamics of the target region (Europe). The database covers 102 "uncoupled" years and 102 Two-Way Coupled years of the recent climate (1960-2010). Results are validated against the ERA-Interim reanalysis. Besides the climatological point of view, the design of this single model ensemble allows for an analysis of the predictability of the first and second leadyears of the hindcasts. As a first step to understand the improved predictability of cyclones, we will show a detailed analysis of climatologies for specific cyclone categories, sorted by season and region. Especially for cyclones affecting Europe, the TWC is capable to counteract the AOGCM's biases in the North Atlantic. Also
Ming Yi WANG; Guo ZHAO
2005-01-01
A right R-module E over a ring R is said to be maximally injective in case for any maximal right ideal m of R, every R-homomorphism f : m → E can be extended to an R-homomorphism f' : R → E. In this paper, we first construct an example to show that maximal injectivity is a proper generalization of injectivity. Then we prove that any right R-module over a left perfect ring R is maximally injective if and only if it is injective. We also give a partial affirmative answer to Faith's conjecture by further investigating the property of maximally injective rings. Finally, we get an approximation to Faith's conjecture, which asserts that every injective right R-module over any left perfect right self-injective ring R is the injective hull of a projective submodule.
Andrew M. Parker
2007-12-01
Full Text Available Our previous research suggests that people reporting a stronger desire to maximize obtain worse life outcomes (Bruine de Bruin et al., 2007. Here, we examine whether this finding may be explained by the decision-making styles of self-reported maximizers. Expanding on Schwartz et al. (2002, we find that self-reported maximizers are more likely to show problematic decision-making styles, as evidenced by self-reports of less behavioral coping, greater dependence on others when making decisions, more avoidance of decision making, and greater tendency to experience regret. Contrary to predictions, self-reported maximizers were more likely to report spontaneous decision making. However, the relationship between self-reported maximizing and worse life outcomes is largely unaffected by controls for measures of other decision-making styles, decision-making competence, and demographic variables.
Brüstle, Thomas; Pérotin, Matthieu
2012-01-01
Maximal green sequences are particular sequences of quiver mutations which were introduced by Keller in the context of quantum dilogarithm identities and independently by Cecotti-Cordova-Vafa in the context of supersymmetric gauge theory. Our aim is to initiate a systematic study of these sequences from a combinatorial point of view. Interpreting maximal green sequences as paths in various natural posets arising in representation theory, we prove the finiteness of the number of maximal green sequences for cluster finite quivers, affine quivers and acyclic quivers with at most three vertices. We also give results concerning the possible numbers and lengths of these maximal green sequences. Finally we describe an algorithm for computing maximal green sequences for arbitrary valued quivers which we used to obtain numerous explicit examples that we present.
Sum-Rate Maximization of Coordinated Direct and Relay Systems
Sun, Fan; Popovski, Petar; Thai, Chan
2012-01-01
Joint processing of multiple communication flows in wireless systems has given rise to a number of novel transmission techniques, notably the two-way relaying based on wireless network coding. Recently, a related set of techniques has emerged, termed coordinated direct and relay (CDR) transmissions......, where the constellation of traffic flows is more general than the two-way. Regardless of the actual traffic flows, in a CDR scheme the relay has a central role in managing the interference and boosting the overall system performance. In this paper we investigate the novel transmission modes, based...
Li, Shan; Li, Laurent; Le Treut, Hervé
2016-04-01
In the 21st century, the estimated surface temperature warming projected by General Circulation Models (GCMs) is between 0.3 and 4.8 °C, depending on the scenario considered. GCMs exhibit a good representation of climate on a global scale, but they are not able to reproduce regional climate processes with the same level of accuracy. Society and policymakers need model projections to define climate change adaptation and mitigation policies on a global, regional and local scale. Climate downscaling is mostly conducted with a regional model nested into the outputs of a global model. This one-way nesting approach is generally used in the climate community without feedbacks from Regional Climate Models (RCMs) to GCMs. This lack of interaction between the two models may affect regional modes of variability, in particular those with a boundary conflict. The objective of this study is to evaluate a two-way nesting configuration that makes an interactive coupling between the RCM and the GCM, an approach against the traditional configuration of one-way nesting system. An additional aim of this work is to examine if the two-way nesting system can improve the RCM performance. The atmospheric component of the IPSL integrated climate model (LMDZ) is configured at both regional (LMDZ-regional) and global (LMDZ-global) scales. The two models have the same configuration for the dynamical framework and the physical forcings. The climatology values of sea surface temperature (SST) are prescribed for the two models. The stretched-grid of LMDZ-global is applied to a region defined by Europe, the Mediterranean, North Africa and Western North Atlantic. To ensure a good statistical significance of results, all simulations last at least 80 years. The nesting process of models is performed by a relaxation procedure of a time scale of 90 minutes. In the case of two-way nesting, the exchange between the two models is every two hours. The relaxation procedure induces a boundary conflict
A Novel Approach Utilizing pnetCDF applying to the WRF-CMAQ two-way coupled model
Wong, David; Yang, Cheng-en; Mathur, Rohit; Pleim, Jonathan; Fu, Joshua; Wong, Kwai; Gao, Yang
2014-05-01
I/O is part of a scientific model and it takes up a significant portion of the simulation. There is no exception for the newly developed WRF-CMAQ two-way coupled model at US EPA. This two-way coupled meteorology and air quality model is composed of the Weather Research and Forecasting (WRF) model and the Community Multiscale Air Quality (CMAQ) model. We are using this two-way model to evaluate how accurate it simulates the effects of aerosol loading on radiative forcing between 1990 and 2010 when there were substantial aerosol emissions such as SO2 and NOx, reduction in North America and Europe. The I/O scheme in the current model does not make use of any parallel file system or parallel I/O approach. In addition the I/O takes about 15% - 28% of the entire simulation. Our novel approach not only utilizes pnetCDF parallel I/O technique but goes one step further to aggregate the data locally, i.e. along column dimension or row dimension in the spatial domain. This approach not only reduces the I/O traffic contention but also aggregated data enhances the I/O efficiency. In terms of I/O time, we have shown this method is about 6 to 10 times faster than the current existing I/O scheme in the model and about 20% - 3 times faster than strict application of pnetCDF. We are currently running the model on a Cray XE6 machine and finding ways to reduce the overall simulation time is crucial to the success to achieve our objective.
Givati, Amir; Gochis, David; Rummler, Thomas; Kunstmann, Harald; Yu, Wei
2016-04-01
A pair of hydro-meteorological modeling systems were calibrated and evaluated for the Ayalon basin in central Israel to assess the advantages and limitations of one-way versus two-way coupled modeling systems for flood prediction. The models used included the Hydrological Engineering Center-Hydrological Modeling System (HEC-HMS) model and the Weather Research and Forecasting (WRF) Hydro modeling system. The models were forced by observed, interpolated precipitation from rain-gauges within the basin, and with modeled precipitation from the WRF atmospheric model. Detailed calibration and evaluation was carried out for two major winter storms in January and December 2013. Then both modeling systems were executed and evaluated in an operational mode for the full 2014/2015 rainy season. Outputs from these simulations were compared to observed measurements from hydrometric stations at the Ayalon basin outlet. Various statistical metrics were employed to quantify and analyze the results: correlation, Root Mean Square Error (RMSE) and the Nash-Sutcliffe (NS) efficiency coefficient. Foremost, the results presented in this study highlight the sensitivity of hydrological responses to different sources of precipitation data, and less so, to hydrologic model formulation. With observed precipitation data both calibrated models closely simulated the observed hydrographs. The two-way coupled WRF/WRF-Hydro modeling system produced improved both the precipitation and hydrological simulations as compared to the one-way WRF simulations. Findings from this study suggest that the use of two-way atmospheric-hydrological coupling has the potential to improve precipitation and, therefore, hydrological forecasts for early flood warning applications. However more research needed in order to better understand the land-atmosphere coupling mechanisms driving hydrometeorological processes on a wider variety precipitation and terrestrial hydrologic systems.
Amir Givati
2016-05-01
Full Text Available A pair of hydro-meteorological modeling systems were calibrated and evaluated for the Ayalon basin in central Israel to assess the advantages and limitations of one-way versus two-way coupled modeling systems for flood prediction. The models used included the Hydrological Engineering Center-Hydrological Modeling System (HEC-HMS model and the Weather Research and Forecasting (WRF Hydro modeling system. The models were forced by observed, interpolated precipitation from rain-gauges within the basin, and with modeled precipitation from the WRF atmospheric model. Detailed calibration and evaluation was carried out for two major winter storms in January and December 2013. Then, both modeling systems were executed and evaluated in an operational mode for the full 2014/2015 rainy season. Outputs from these simulations were compared to observed measurements from the hydrometric station at the Ayalon basin outlet. Various statistical metrics were employed to quantify and analyze the results: correlation, Root Mean Square Error (RMSE and the Nash–Sutcliffe (NS efficiency coefficient. Foremost, the results presented in this study highlight the sensitivity of hydrological responses to different sources of simulated and observed precipitation data, and demonstrate improvement, although not significant, at the Hydrological response, like simulated hydrographs. With observed precipitation data both calibrated models closely simulated the observed hydrographs. The two-way coupled WRF/WRF-Hydro modeling system produced improved both the precipitation and hydrological simulations as compared to the one-way WRF simulations. Findings from this study, as well as previous studies, suggest that the use of two-way atmospheric-hydrological coupling has the potential to improve precipitation and, therefore, hydrological forecasts for early flood warning applications. However, more research needed in order to better understand the land-atmosphere coupling mechanisms
Journal Editors
2001-03-01
Full Text Available This report was written on a request from the Minister of Health, Welfare and Sport, in response to the need to bridge the gap between scientific research and the implementation of the results of this research into the practice of health care. The report concludes that the care process should be a two-way dialogue between science and practice, and signals the need for more research into everyday practice, while this research might benefit from insights from other branches of the sciences.
Yang, Liang
2013-04-01
In this paper, we consider the performance of a two-way amplify-and-forward relaying network (AF TWRN) in the presence of unequal power co-channel interferers (CCI). Specifically, we consider AF TWRN with an interference-limited relay and two noisy-nodes with channel estimation error and CCI. We derive the approximate signal-to-interference plus noise ratio expressions and then use these expressions to evaluate the outage probability and error probability. Numerical results show that the approximate closed-form expressions are very close to the exact ones. © 2013 IEEE.
An R function for imputation of missing cells in two-way data sets by EM-AMMI algorithm
Jakub Paderewski
2014-06-01
Full Text Available Various statistical methods for two-way classification data sets (including AMMI or GGE analyses, used in crop science for interpreting genotype-by-environment interaction require the data to be complete, that is, not to have missing cells. If there are such, however, one might impute the missing cells. The paper offers R code for imputing missing values by the EM-AMMI algorithm. In addition, a function to check the repeatability of this algorithm is proposed. This function could be used to evaluate if the missing data were imputed reliably (unambiguously, which is important especially for small data sets
Rudiger Bubner
1998-12-01
Full Text Available Even though the maxims' theory is not at thecenter of Kant's ethics, it is the unavoidable basis of the categoric imperative's formulation. Kant leanson the transmitted representations of modem moral theory. During the last decades, the notion of maxims has deserved more attention, due to the philosophy of language's debates on rules, and due to action theory's interest in this notion. I here by brietly expound my views in these discussions.
Alsharoa, Ahmad
2015-10-08
This paper studies the achievable cognitive sum rate of an overlay cognitive radio (CR) system assisted with multiple antennas two-way relays in which primary users (PUs) cooperate with cognitive users (CUs) for mutual benefits. In this context, the problem of both bandwidth and power allocation is investigated. We propose that the CUs are allowed to allocate a part of the PUs spectrum to perform their cognitive transmission. In return, acting as amplify-and-forward two-way relays, they are exploited to support PUs to reach their target data rates over the remaining bandwidth. Power expressions for optimal transmit power allocated per PU and CU antenna are derived under primary quality-of-service constraint in addition to bandwidth and power budget constraints. More specifically, CUs act as relays for the PUs transmission and gain some spectrum as long as they respect these constraints. After deriving the optimal transmit powers, we employ a strong optimization tool based on swarm intelligence to optimize the full and complex relay amplification gain matrices in addition to the bandwidths released to primary and cognitive transmission. Furthermore, three different utility functions are considered in our optimization problems depending on the level of fairness among CUs.
Fang, L.; Yang, X. H.; Sun, B. Q.; Qin, W. J.; Kong, Y.
2013-09-01
The measurement of the inter-satellite link is one of the key techniques in the autonomous operation of satellite navigation system. Based on the asynchronism inter-satellite two-way measurement mode in GPS constellation, the reduction formula of the inter-satellite time synchronization is built in this paper. Moreover, the corrective method of main systematic errors is proposed. Inter-satellite two-way time synchronization is simulated on the basis of IGS (International GNSS Service) precise ephemeris. The impacts of the epoch domestication of asynchronism inter-satellite link pseudo-range, the initial orbit, and the main systematic errors on satellite time synchronization are analyzed. Furthermore, the broadcast clock error of each satellite is calculated by the ``centralized'' inter-satellite autonomous time synchronization. Simulation results show that the epoch domestication of asynchronism inter-satellite link pseudo-range and the initial orbit have little impact on the satellite clock errors, and thus they needn't be taken into account. The errors caused by the relativistic effect and the asymmetry of path travel have large impact on the satellite clock errors. These should be corrected with theoretical formula. Compared with the IGS precise clock error, the root mean square of the broadcast clock error of each satellite is about 0.4 ns.
Role of B19' martensite deformation in stabilizing two-way shape memory behavior in NiTi
Benafan, O.; Padula, S. A.; Noebe, R. D.; Sisneros, T. A.; Vaidyanathan, R.
2012-11-01
Deformation of a B19' martensitic, polycrystalline Ni49.9Ti50.1 (at. %) shape memory alloy and its influence on the magnitude and stability of the ensuing two-way shape memory effect (TWSME) was investigated by combined ex situ mechanical experimentation and in situ neutron diffraction measurements at stress and temperature. The microstructural changes (texture, lattice strains, and phase fractions) during room-temperature deformation and subsequent thermal cycling were captured and compared to the bulk macroscopic response of the alloy. With increasing uniaxial strain, it was observed that B19' martensite deformed by reorientation and detwinning with preferred selection of the (1¯50)M and (010)M variants, (201¯)B19' deformation twinning, and dislocation activity. These mechanisms were indicated by changes in bulk texture from the neutron diffraction measurements. Partial reversibility of the reoriented variants and deformation twins was also captured upon load removal and thermal cycling, which after isothermal deformation to strains between 6% and 22% resulted in a strong TWSME. Consequently, TWSME functional parameters including TWSME strain, strain reduction, and transformation temperatures were characterized and it was found that prior martensite deformation to 14% strain provided the optimum condition for the TWSME, resulting in a stable two-way shape memory strain of 2.2%. Thus, isothermal deformation of martensite was found to be a quick and efficient method for creating a strong and stable TWSME in Ni49.9Ti50.1.
EFFECTS OF THE NUMBER OF RELAY ANTENNAS AND RELAY-POWER ON MIMO PRECODED TWO-WAY RELAYING
S.S. Rajeshwari
2011-06-01
Full Text Available In this treatise a two-way Amplify and Forward (AF relay-aided system is considered, which employs the so-called Arithmetic Sum of Average Bit Error Rate (ASABER based MIMO precoding technique. The two-way AF relay system is comprised of the pair of transceiver nodes S1 and S2, and the Relay Node (RN R, where each node is equipped with N1, N2 and Nr antennas, respectively. We study the effects of varying Nr for fixed values of N1 and N2, and as well as the effects of having a fixed transmission power at the RN on the achievable ASABER performance. Based on our intensive simulation campaign, we infer that the attainable diversity order is increased approximately by Nr − min (N1, N2, whenever Nr assumes a value higher than min (N1, N2 for fixed N1, N2 values. However, this is observation is only valid for relay power pr ≥ (p1, p2, where p1 and p2 are the transmit power constraints imposed on the sources S1 and S2, respectively. We also observe that the ASABER MIMO precoder’s BER curve exhibits an error floor for pr ≤ (p1, p2.
Wu, Xiaolin; Rong, Yue
2015-12-01
The quality-of-service (QoS) criteria (measured in terms of the minimum capacity requirement in this paper) are very important to practical indoor power line communication (PLC) applications as they greatly affect the user experience. With a two-way multicarrier relay configuration, in this paper we investigate the joint terminals and relay power optimization for the indoor broadband PLC environment, where the relay node works in the amplify-and-forward (AF) mode. As the QoS-constrained power allocation problem is highly non-convex, the globally optimal solution is computationally intractable to obtain. To overcome this challenge, we propose an alternating optimization (AO) method to decompose this problem into three convex/quasi-convex sub-problems. Simulation results demonstrate the fast convergence of the proposed algorithm under practical PLC channel conditions. Compared with the conventional bidirectional direct transmission (BDT) system, the relay-assisted two-way information exchange (R2WX) scheme can meet the same QoS requirement with less total power consumption.
Robert, Clélia; Conan, Jean-Marc; Wolf, Peter
2016-06-01
Bidirectional ground-satellite laser links suffer from turbulence-induced scintillation and phase distortion. We study how turbulence impacts on coherent detection capacity and on the associated phase noise that restricts clock transfer precision. We evaluate the capacity to obtain a two-way cancellation of atmospheric effects despite the asymmetry between up and down link that limits the link reciprocity. For ground-satellite links, the asymmetry is induced by point-ahead angle and possibly the use, for the ground terminal, of different transceiver diameters, in reception and emission. The quantitative analysis is obtained thanks to refined end- to-end simulations under realistic turbulence and wind conditions as well as satellite cinematic. These temporally resolved simulations allow characterizing the coherent detection in terms of time series of heterodyne efficiency for different system parameters. We show that Tip/Tilt correction on ground is mandatory at reception for the down link and as a pre-compensation of the up link. Good correlation between up and down phase noise is obtained even with asymmetric apertures of the ground transceiver and in spite of pointing ahead angle. The reduction to less than 1 rad2 of the two-way differential phase noise is very promising for clock comparisons.
Design and implementation of a two-way real-time communication system for audio over CATV networks
Cho, Choong Sang; Oh, Yoo Rhee; Lee, Young Han; Kim, Hong Kook
2007-09-01
In this paper, we design and implement a two-way real-time communication system for audio over cable television (CATV) networks to provide an audio-based interaction between the CATV broadcasting station and CATV subscribers. The two-way real-time communication system consists of a real-time audio encoding/decoding module, a payload formatter based on a transmission control protocol/Internet protocol (TCP/IP), and a cable network. At the broadcasting station, audio signals from a microphone are encoded by an audio codec that is implemented using a digital signal processor (DSP), where the MPEG-2 Layer II audio codec is used for the audio codec and TMS320C6416 is used for a DSP. Next, a payload formatter constructs a TCP/IP packet from an audio bitstream for transmission to a cable modem. Another payload formatter at the subscriber unpacks the TCP/IP packet decoded from the cable modem into audio bitstream. This bitstream is decoded by the MPEG-2 Layer II audio decoder. Finally the decoded audio signals are played out to the speaker. We confirmed that the system worked in real-time, with a measured delay of around 150 ms including the algorithmic and processing time delays.
Zhou, ShanShi; Hu, XiaoGong; Liu, Li; Guo, Rui; Zhu, LingFeng; Chang, ZhiQiao; Tang, ChengPan; Gong, XiuQiang; Li, Ran; Yu, Yang
2016-10-01
A two-way satellite time and frequency transfer (TWSTFT) device equipped in the BeiDou navigation satellite system (BDS) can calculate clock error between satellite and ground master clock. TWSTFT is a real-time method with high accuracy because most system errors such as orbital error, station position error, and tropospheric and ionospheric delay error can be eliminated by calculating the two-way pseudorange difference. Another method, the multi-satellite precision orbit determination (MPOD) method, can be applied to estimate satellite clock errors. By comparison with MPOD clock estimations, this paper discusses the applications of the BDS TWSTFT clock observations in satellite clock measurement, satellite clock prediction, navigation system time monitor, and satellite clock performance assessment in orbit. The results show that with TWSTFT clock observations, the accuracy of satellite clock prediction is higher than MPOD. Five continuous weeks of comparisons with three international GNSS Service (IGS) analysis centers (ACs) show that the reference time difference between BeiDou time (BDT) and golbal positoning system (GPS) time (GPST) realized IGS ACs is in the tens of nanoseconds. Applying the TWSTFT clock error observations may obtain more accurate satellite clock performance evaluation in the 104 s interval because the accuracy of the MPOD clock estimation is not sufficiently high. By comparing the BDS and GPS satellite clock performance, we found that the BDS clock stability at the 103 s interval is approximately 10-12, which is similar to the GPS IIR.
Myhr, Geir Ove
2010-11-08
Just like we can divide the set of bipartite quantum states into separable states and entangled states, we can divide it into states with and without a symmetric extension. The states with a symmetric extension - which includes all the separable states - behave classically in many ways, while the states without a symmetric extension - which are all entangled - have the potential to exhibit quantum effects. The set of states with a symmetric extension is closed under local quantum operations assisted by one-way classical communication (1-LOCC) just like the set of separable states is closed under local operations assisted by two-way classical communication (LOCC). Because of this, states with a symmetric extension often play the same role in a one-way communication setting as the separable states play in a two-way communication setting. We show that any state with a symmetric extension can be decomposed into a convex combination of states that have a pure symmetric extension. A necessary condition for a state to have a pure symmetric extension is that the spectra of the local and global density matrices are equal. This condition is also sufficient for two qubits, but not for any larger systems. We present a conjectured necessary and sufficient condition for two-qubit states with a symmetric extension. Proofs are provided for some classes of states: rank-two states, states on the symmetric subspace, Bell-diagonal states and states that are invariant under S x S, where S is a phase gate. We also show how the symmetric extension problem for multi-qubit Bell-diagonal states can be simplified and the simplified problem implemented as a semidefinite program. Quantum key distribution protocols such as the six-state protocol and the BB84 protocol effectively gives Alice and Bob Bell-diagonal states that they measure in the standard basis to obtain a raw key which they may then process further to obtain a secret error-free key. When the raw key has a high error rate, the
Al-Eryani, Yasser F.
2017-07-20
In this paper, the performance of two-way relaying (TWR) multiuser mixed radio frequency/free space optical (RF/FSO) relay networks with opportunistic user scheduling and asymmetric channel fading is studied. First, closed-form expressions for the exact outage probability, asymptotic (high signal-to-noise ration (SNR)) outage probability, and average ergodic channel capacity are derived assuming heterodyne detection (HD) scheme. Additionally, impacts of several system parameters including number of users, pointing errors, and atmospheric turbulence conditions on the overall network performance are investigated. All the theoretical results are validated by Monte-Carlo simulations. The results show that the TWR scheme almost doubles the network ergodic capacity compared to that of one-way relaying (OWR) scheme with the same outage performance. Additionally, the overall diversity order of the network is shown to be affected not only by the number of users, but it is also a function of the pointing error and atmospheric turbulence conditions.
Hwang, Kyusung
2011-02-01
In this letter, we propose two-way amplify-and-forward relaying in conjunction with adaptive modulation in order to improve spectral efficiency of relayed communication systems while monitoring the required error performance. We also consider a multiple relay network where only the best relay node is utilized so that the diversity order increases while maintaining a low complexity of implementation as the number of relays increases. Based on the best relay selection criterion, we offer an upper bound on the signal-to-noise ratio to keep the performance analysis tractable. Our numerical examples show that the proposed system offers a considerable gain in spectral efficiency while satisfying the error rate requirements. © 2011 IEEE.
Hu, Chia-Chang; Su, Hao-Hsian; Tang, Kang-Tsao
2014-09-01
This paper considers a two-way multiple-input multiple-output (MIMO) relaying system with multiple relays between two terminals nodes. The relay antenna selection scheme based on channel singular valued decomposition (SVD) is used to reduce energy consumption. To enhance the system performance, we apply a SVD-based algorithm with MSE criterion which calculates optimal linear transceivers precoding jointly at the source nodes and relay nodes for amplify-and-forward (AF) protocols. In computer simulations, we use an iteration method to compute the non-convex function of joint source and relays power allocation. The simulation results show the SVD-based precoding design with SVD-based relay and antenna selection scheme can achieve a superior system bit error rate (BER) performance and reduce the power consume of relay antennas.
Schreuer, Naomi; Keter, Ayala; Sachs, Dalia
2014-01-01
The current study examined by mixed method the effectiveness of an accessibility to Information and Communications Technology (ICT) program that provided computers, assistive technology, tutors, and internet connection to 65 youths with severe disabilities (aged 13.22 ± 3.4 years) in their homes. The quantitative evaluation included assessment of computer task performance, computer skills, and participation in social ICT leisure activities before and after the program. Findings revealed low baseline and significant progress on most outcome measures 6 months after the program, mostly among those youths who had tutors. Additional in-depth interviews were conducted 1 year later with 10 participants to explore their ICT use and its impact on their social participation. The analysis revealed a significant contribution of the ICT use, while critical thinking about its risks and some disappointment with the social needs that ICT does not address. Our findings raise awareness of 'two-way streets' policies and programs to ensure e-inclusion.
Xavier, G B; da Silva, T Ferreira; Temporao, G P; von der Weid, J P
2009-01-01
We experimentally show a two-way transmission of polarization encoded pseudo-single photons between two remote parties separated by a single 23 km optical fiber spool. Two optical classical channels are wavelength multiplexed in the same fiber and used as feedback to an active polarization drift compensation scheme. One of the classical channels contains a 10 Gb/s data stream simulating real telecom traffic. The feasibility of quantum communication is demonstrated in the fiber's two opposite directions of propagation over 6 hours of continuous operation, as well as a classical error rate in the data channel better than 1.0 x 10-9. The results are extended to show the estimated maximum transmission distance for the quantum signals based on the noise generated through Raman spontaneous scattering by up to 16 classical channels present in the fiber.
Rodrigo Salvador
2017-07-01
Full Text Available Initiatives toward Lean and Green Manufacturing are given mainly due to organisational response to current market’s economic and environmental pressures. This paper, therefore, aims to present a brief discussion based on a literature review of the potential two-way influence between Lean and Green Manufacturing and its role on the main organisational areas with a closer relationship to such approaches, which were observed to be more extensively discussed in the literature. Naturally lean practises seem more likely to deploy into green outcomes, though the other way around can also occur. There is some blur on the factual integration of both themes, as some authors suggest. Notwhithstanding, they certainly present certain synergy. Thereupon, further research is needed to unveil the real ties, overlaps and gaps between these approaches.
Hwang, Kyusung
2013-09-01
In this paper, we study the outage performance of an amplify-and-forward (AF)-based two-way relaying (TWR) system with multiple relays where a single relay selection is performed based on outdated channel state information (CSI). Specifically, we propose a single relay selection scheme in AF-based TWR system under outdated CSI conditions. With this policy, we offer a statistical analysis of the signal-to-noise ratio per hop and analyze the outage probability with asymmetric outage thresholds based on CSI-assisted AF protocol. Additionally, we provide the exact and asymptotic expressions based on the provided statistical/joint statistical analyses of a dual-hop AF transmission. Finally, we verify our analytical results with some selected computer-based simulation results. © 1972-2012 IEEE.
Friedrich-Karl Benra
2011-01-01
Full Text Available The interaction between fluid and structure occurs in a wide range of engineering problems. The solution for such problems is based on the relations of continuum mechanics and is mostly solved with numerical methods. It is a computational challenge to solve such problems because of the complex geometries, intricate physics of fluids, and complicated fluid-structure interactions. The way in which the interaction between fluid and solid is described gives the largest opportunity for reducing the computational effort. One possibility for reducing the computational effort of fluid-structure simulations is the use of one-way coupled simulations. In this paper, different problems are investigated with one-way and two-way coupled methods. After an explanation of the solution strategy for both models, a closer look at the differences between these methods will be provided, and it will be shown under what conditions a one-way coupling solution gives plausible results.
Comparison of hydro-environmental impacts for ebb-only and two-way generation for a Severn Barrage
Ahmadian, Reza; Falconer, Roger A.; Bockelmann-Evans, Bettina
2014-10-01
Marine renewable energy is playing an increasing significant role in many parts of the world, mainly due to a rise in the awareness of climate change, and its detrimental effects, and the increasing cost of natural resources. The Severn Estuary, located between South West England and South Wales, has a tidal range of up to 14 m which makes it the second highest tidal range in the world. There are a number of barrage proposals amongst various marine renewable energy schemes proposed to be built in the estuary. The Cardiff-Weston STPG (Severn Tidal Power Group) Barrage, which would be one of the world's largest tidal renewable energy schemes if built, is one of the most publicised schemes to-date. This barrage would generate about 17 TWh/annum of power, which is approximately 5% of the UK's electricity consumption, whilst causing significant hydro-environmental and ecological impact on the estuary. This study mainly focuses on investigating the hydro-environmental impacts of the STPG barrage for the option of two-way generation, and compares this with the commonly investigated option of ebb-only generation. The impacts of the barrage were modelled by implementing a linked 1-D/2-D hydro-environmental model, with the capability of modelling several key environmental processes. The model predictions show that the hydro-environmental impacts of the barrage on the Severn Estuary and Bristol Channel, such as changes in the maximum velocity and reduction in suspended sediment and bacteria levels, were less significant for the two-way generation scheme when compared with the corresponding impacts for ebb-only generation.
Hauk, Markus; Pail, Roland; Murböck, Michael; Schlicht, Anja
2016-04-01
For the determination of temporal gravity fields satellite missions such as GRACE (Gravity Recovery and Climate Experiment) or CHAMP (Challenging Minisatellite Payload) were used in the last decade. These missions improved the knowledge of atmospheric, oceanic and tidal mass variations. The most limiting factor of temporal gravity retrieval quality is temporal aliasing due to the undersampling of high frequency signals, especially in the atmosphere and oceans. This kind of error causes the typical stripes in spatial representations of global gravity fields such as from GRACE. As part of the GETRIS (Geodesy and Time Reference in Space) mission, that aims to establish a geodetic reference station and precise time- and frequency reference in space by using optical two-way communication links between geostationary (GEO) and low Earth orbiting (LEO) satellites, a possible future gravity field mission can be set up. By expanding the GETRIS space segment to the global satellite navigation systems (GNSS) the optical two-way links also connect the GALILEO satellites among themselves and to LEO satellites. From these links between GALILEO and LEO satellites gravitational information can be extracted. In our simulations inter-satellite links between GALILEO and LEO satellites are used to determine temporal changes in the Earth's gravitational field. One of the main goals of this work is to find a suitable constellation together with the best analysis method to reduce temporal aliasing errors. Concerning non-tidal aliasing, it could be shown that the co-estimation of short-period long-wavelength gravity field signals, the so-called Wiese approach, is a powerful method for aliasing reduction (Wiese et al. 2013). By means of a closed loop mission simulator using inter-satellite observations as acceleration differences along the line-of-sight, different mission scenarios for GALILEO-LEO inter-satellite links and different functional models like the Wiese approach are analysed.
Two-way Transformation Scheme of EPON+EoC%EPON+EoC双向改造方案
解立伟; 李跃辉; 任勋益; 马晓东; 陈小星
2011-01-01
During the digital convergence process, which is the integration of telecom, CATV and Intender, there is new challenge for the CATV network. It is crucial to choose appropriate reform technology for the CATV network. Introduces the two-way transformation scheme of CATV network. According to the detailed analysis and comparison of three networking technologies, such as CMTS + CM,Elan + LAN, EPON + EoC. Furthermore, EoC-related technologies are explained in detail, from the business performance, the cost of construction and the complexity of transformation. The conclusion can be reached that EPON + EoC is the most suitable choice for the current two-way transformation and the subsequent convergence of three networks. However, it is suggested that the transformation of CATV network be based upon the actual situation.%目前在电信网、广播电视网和互联网三网逐步融合的背景下,有线电视网络面临前所未有的挑战.使用何种改造方案来实现双向网络的改造就显得尤为重要.介绍了广电网络双向改造的技术方案及其特点,对有线电视网络双向改造使用的CMTS+CM,EPON十LAN,EPON+Eo(;三种方案的优劣进行了分析和比较,对Eo(:技术进行了详细论述.从业务性能、建设成本、改造技术复杂程度等方面进行分析,最终认为EPON+EoC是广电网络双向改造、实现三网融合的最佳方案.广电网络运营商应根据实际情况,选择适合的EoC方案.
Janusz Brzozowski
2014-05-01
Full Text Available The atoms of a regular language are non-empty intersections of complemented and uncomplemented quotients of the language. Tight upper bounds on the number of atoms of a language and on the quotient complexities of atoms are known. We introduce a new class of regular languages, called the maximally atomic languages, consisting of all languages meeting these bounds. We prove the following result: If L is a regular language of quotient complexity n and G is the subgroup of permutations in the transition semigroup T of the minimal DFA of L, then L is maximally atomic if and only if G is transitive on k-subsets of 1,...,n for 0 <= k <= n and T contains a transformation of rank n-1.
Mao, Dongyao; Geng, Yaohui; Liu, Hongpeng; Zhou, Ke; Xian, Lihong; Yu, Dan
2016-08-10
Holographic sensing of alcohol organic vapor is characterized in detail at transmission and reflection geometries in Y nanozeolites dispersed acrylamide photopolymer. The two-way shift of the diffraction spectrum and its temporal evolution with various vapor concentrations are measured. Obvious blueshifts of diffraction spectrum peaks are observed and analyzed in two recording geometries. The competition mechanism between decreasing the average refractive index and swelling the grating fringe space is proposed for exploring the wavelength shift mechanism. In the reflection grating, as organic vapor increases, the redshift after the blueshift of the wavelength peaks are observed clearly. We further demonstrate the significance of this competition mechanism. In the low concentration region, at transmission blueshift of the wavelength is a significant factor in identifying an organic vapor with a low refractive index. These experimental results provide a probability for improving the applicability of a holographic sensor. This work can accelerate the development of the holographic sensing strategy and provide a novel identification method for organic vapor.
Two-way shape memory effect and alternating current driving characteristics of a TiNi alloy spring
WANG Zhiguo; ZU Xiaotao
2004-01-01
Two-way shape memory effect (TWSME) was induced into the TiNi shape memory alloys (SMAs) spring by thermomechanical training after annealing treatment, which has promising application in micro-actuating fields. The TWSME spring can contract upon heating and extend upon cooling. The results show that there is an increase of the recovery ratio up to a maximum TWSME of 45%. During the training procedure, transformation temperatures and hysteresis were measured by different scanning calorimetry (DSC). The results show that As (reverse transformation start temperature) and Af (revere transformation finish temperature) shift to lower temperature after training. The intervals of Af-As and Ms-Mr (Ms and Mf are the martensite start and finish temperatures, respectively) increase and the heat of transformation decreases after training. The electrothermal driving characteristics of the TWSME springs were also investigated with alternating current density of 3.2-14.7 A/mm2. It is found that the time response and the maximum contraction ratio greatly depend on the magnitude of the electrical current density.
Jana Zelenkova
2017-06-01
Full Text Available The exponential Phan–Tien and Tanner (PTT, Giesekus, Leonov, and modified extended Pom–Pom (mXPP differential constitutive models are evaluated in two ways: with regard to steady shear characteristics and with regard to large amplitude oscillatory shear characteristics of a solution of poly(ethylene oxide in dimethyl sulfoxide. Efficiency of the models with nonlinear parameters optimized with respect to steady shear measurements is evaluated by their ability to describe large amplitude oscillatory shear (LAOS characteristics. The reciprocal problem is also analyzed: The nonlinear parameters are optimized with respect to the LAOS measurements, and the models are confronted with the steady shear characteristics. In this case, optimization is based on the LAOS measurements and equal emphasis is placed on both real and imaginary parts of the stress amplitude. The results show that the chosen models are not adequately able to fit the LAOS characteristics if the optimization of nonlinear parameters is based on steady shear measurements. It follows that the optimization of nonlinear parameters is much more responsible if it is carried out with respect to the LAOS data. In this case, when the optimized parameters are used for a description of steady shear characteristics, efficiency of the individual models as documented differs.
Milani, Gabriele, E-mail: milani@stru.polimi.it [Department of Architecture, Built Environment and Construction Engineering (ABC), Politecnico diMilano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Olivito, Renato S. [Dipartimento di Ingegneria Civile - Università della Calabria Via P Bucci 39 B - 87036 RENDE (CS) (Italy); Tralli, Antonio [Department of Engineering, University of Ferrara, Via Saragat 1, 44100 Ferrara (Italy)
2014-10-06
The buckling behavior of slender unreinforced masonry (URM) walls subjected to axial compression and out-of-plane lateral loads is investigated through a combined experimental and numerical homogenizedapproach. After a preliminary analysis performed on a unit cell meshed by means of elastic FEs and non-linear interfaces, macroscopic moment-curvature diagrams so obtained are implemented at a structural level, discretizing masonry by means of rigid triangular elements and non-linear interfaces. The non-linear incremental response of the structure is accounted for a specific quadratic programming routine. In parallel, a wide experimental campaign is conducted on walls in two way bending, with the double aim of both validating the numerical model and investigating the behavior of walls that may not be reduced to simple cantilevers or simply supported beams. Panels investigated are dry-joint in scale square walls simply supported at the base and on a vertical edge, exhibiting the classical Rondelet’s mechanism. The results obtained are compared with those provided by the numerical model.
Eigen-Direction Alignment Based Physical-Layer Network Coding for MIMO Two-Way Relay Channels
Yang, Tao; Ping, Li; Collings, Iain B; Yuan, Jinhong
2012-01-01
In this paper, we propose a novel communication strategy which incorporates physical-layer network coding (PNC) into multiple-input multiple output (MIMO) two-way relay channels (TWRCs). At the heart of the proposed scheme lies a new key technique referred to as eigen-direction alignment (EDA) precoding. The EDA precoding efficiently aligns the two-user's eigen-modes into the same directions. Based on that, we carry out multi-stream PNC over the aligned eigen-modes. We derive an achievable rate of the proposed EDA-PNC scheme, based on nested lattice codes, over a MIMO TWRC. Asymptotic analysis shows that the proposed EDA-PNC scheme approaches the capacity upper bound as the number of user antennas increases towards infinity. For a finite number of user antennas, we formulate the design criterion of the optimal EDA precoder and present solutions. Numerical results show that there is only a marginal gap between the achievable rate of the proposed EDA-PNC scheme and the capacity upper bound of the MIMO TWRC, in ...
Liang Yang,
2013-06-01
In this paper, we consider the performance of a two-way amplify-and-forward relaying network (AF TWRN) in the presence of unequal power co-channel interferers (CCI). Specifically, we first consider AF TWRN with an interference-limited relay and two noisy-nodes with channel estimation errors and CCI. We derive the approximate signal-to-interference plus noise ratio expressions and then use them to evaluate the outage probability, error probability, and achievable rate. Subsequently, to investigate the joint effects of the channel estimation error and CCI on the system performance, we extend our analysis to a multiple-relay network and derive several asymptotic performance expressions. For comparison purposes, we also provide the analysis for the relay selection scheme under the total power constraint at the relays. For AF TWRN with channel estimation error and CCI, numerical results show that the performance of the relay selection scheme is not always better than that of the all-relay participating case. In particular, the relay selection scheme can improve the system performance in the case of high power levels at the sources and small powers at the relays.
Ilie, Raluca; Liemohn, Michael; Toth, Gabor
2014-05-01
The geomagnetic storm of August 6, 2011 is examined using the two-way self consistent coupling between the kinetic Hot Electron and Ion Drift Integrator (HEIDI) model, the Block Adaptive Tree Solar Wind Roes-Type Scheme (BATS-R-US) MHD model and the Ridley Ionospheric Model (RIM) through the Space Weather Modeling Framework (SWMF). HEIDI solves the time dependent, gyration and bounce-averaged kinetic equation for the phase space density of different ring current species and computes full pitch angle distributions for all local times and radial distances. This model was generalized to accommodate arbitrary magnetic fields and through the coupling with the SWMF it obtains magnetic field description along with plasma distribution at the model boundaries from the BATS-R-US model within the SWMF. Electric field self-consistency is assured by the passing of convection potentials from the Ridley Ionosphere Model (RIM) within SWMF. Our study tests the various levels of coupling between the three models, highlighting the role the magnetic field, plasma sheet conditions and the cross polar cap potential play in the formation and evolution of the ring current. We use the results of the coupled HEIDI, BATSRUS and RIM models during disturbed conditions to study the importance of a kinetic self-consistent approach to the description of geospace.
Zhao Yang
2015-01-01
Full Text Available This paper aims to estimate the impacts of pedestrians on capacity and average control delay for the major street through traffic at two-way stop-controlled (TWSC intersections. A procedure was proposed to estimate the expected delay for major street through vehicles based on the pedestrian arrival time and motorist yielding behavior. Field data were collected to calibrate the crucial parameters in the established models. The proposed models were then validated against field measured data. It was found that the calibrated models provided reasonable delay estimates. Based on the established models, sensitivity analyses were conducted to identify the effects of pedestrian arrival rate and motorist yield rate on the capacity of the major street through lanes at TWSC intersections. The results suggested that the capacity of the through movement would decrease with an increase in the pedestrian arrival rate. It was also found that, with the same pedestrian arrival rate, the capacity would decrease as the motorist yield rate became higher, and the magnitude of the capacity reduction would increase with an increase in the pedestrian arrival rate.
Ivanova, Anastasia; Tamura, Roy N
2015-12-01
A new clinical trial design, designated the two-way enriched design (TED), is introduced, which augments the standard randomized placebo-controlled trial with second-stage enrichment designs in placebo non-responders and drug responders. The trial is run in two stages. In the first stage, patients are randomized between drug and placebo. In the second stage, placebo non-responders are re-randomized between drug and placebo and drug responders are re-randomized between drug and placebo. All first-stage data, and second-stage data from first-stage placebo non-responders and first-stage drug responders, are utilized in the efficacy analysis. The authors developed one, two and three degrees of freedom score tests for treatment effect in the TED and give formulae for asymptotic power and for sample size computations. The authors compute the optimal allocation ratio between drug and placebo in the first stage for the TED and compare the operating characteristics of the design to the standard parallel clinical trial, placebo lead-in and randomized withdrawal designs. Two motivating examples from different disease areas are presented to illustrate the possible design considerations.
Løvholt, Finn; Norèn-Cosgriff, Karin; Madshus, Christian; Ellingsen, Ståle Engvik
2017-05-01
Aircraft, supersonic flights, blasts, and explosions emit sound with substantial energy below 100 Hz. When the low frequency sound is transmitted inside a building, it generates vibration and rattling that may lead to annoyance. Our understanding of these low frequency phenomena is presently limited. In this paper, we attempt to improve our computational capabilities related to the low frequency sound transmission. For this purpose, a finite element methodology that incorporates a two-way coupled fluid-structure interaction, has been developed. Results from a broad experimental investigation of low frequency sound transmission are compared with the numerical finite element simulations. Plain walls, and walls with windows are studied. Close agreement between the simulations and the laboratory measurement data is obtained in the frequency range investigated (10-100 Hz). It was found that structural connections were of large importance for modeling the vibration and sound transmission. The windows control the low frequency transmission from 15 to 30 Hz, whereas the walls control the sound transmission from 30 to 100 Hz. Mitigation of vibrations and rattling induced by low frequency sound therefore needs to consider both wall and window construction.
Bercy, Anthony; Stefani, Fabio; Lopez, Olivier; Chardonnet, Christian; Pottie, Paul-Eric; Amy-Klein, Anne
2014-12-01
By using two-way frequency transfer, we implement a real-time frequency comparison over a uni-directional telecommunication network of 100 km using a pair of parallel fibers with simultaneous digital data transfer. The relative frequency stability is 10-15 at 1-s integration time and reaches 2 ×10-17 at 40 000 s, three orders of magnitude below the one-way fiber instability. We also demonstrate ultrahigh-resolution comparison of optical frequencies with a bidirectional scheme using a single fiber. We show that the relative stability at 1-s integration time is 7 ×10-18 and scales down to 5 ×10-21 . The same level of performance is reached when an optical link is implemented with an active compensation of the fiber noise. The fractional uncertainty of the frequency comparisons was evaluated for the best case to 2 ×10-20 . These results open the way to accurate and high-resolution frequency comparison of optical clocks over intercontinental fiber networks.
María Ruiz-Carreras
2010-01-01
Full Text Available This research presents blogs as an innovative and rich tool for political communication. Blogs can facilitate two-way communication and true interaction between citizens and politicians. The article analyses in depth the content, uses, and characteristics of five weblogs written by Aragonese politicians. Although the study detects some weaknesses in the current political use of blogs, it encourages political parties to use blogs and other online resources, not only during electoral campaigns to improve the reputation of political leaders but also continuously and particularly in situations of special interest for the citizenship. The study shows that the use of blogs by Aragonese politicians is no longer just a transitory phenomenon and has become a reality. The article also demonstrates that politicians use blogs mostly as a pre-electoral tooland to a much lesser extent as an element of communication to promote democracy. It has been observed that politicians’ blogs are used as a tool to overcome situations of crisis and to compensate negative opinions caused by questionable acts.
Guest-Induced Two-Way Structural Transformation in a Layered Metal-Organic Framework Thin Film.
Haraguchi, Tomoyuki; Otsubo, Kazuya; Sakata, Osami; Fujiwara, Akihiko; Kitagawa, Hiroshi
2016-12-28
Fabrication of thin films made of metal-organic frameworks (MOFs) has been intensively pursued for practical applications that use the structural response of MOFs. However, to date, only physisorption-induced structural response has been studied in these films. Chemisorption can be expected to provide a remarkable structural response because of the formation of bonds between guest molecules and reactive metal sites in host MOFs. Here, we report that chemisorption-induced two-way structural transformation in a nanometer-sized MOF thin film. We prepared a two-dimensional layered-type MOF Fe[Pt(CN)4] thin film using a step-by-step approach. Although the as-synthesized film showed poor crystallinity, the dehydrated form of this thin film had a highly oriented crystalline nature (Film-D) as confirmed by synchrotron X-ray diffraction (XRD). Surprisingly, under water and pyridine vapors, Film-D showed chemisorption-induced dynamic structural transformations to Fe(L)2[Pt(CN)4] thin films [L = H2O (Film-H), pyridine (Film-P)], where water and pyridine coordinated to the open Fe(2+) site. Dynamic structural transformations were also confirmed by in situ XRD, sorption measurement, and infrared reflection absorption spectroscopy. This is the first report of chemisorption-induced dynamic structural response in a MOF thin film, and it provides useful insights, which would lead to future practical applications of MOFs utilizing chemisorption-induced structural responses.
Thomas, Yvonne; Judd, Jenni
2015-08-01
A novel application of the concept of a community of practice was adopted in the development of a revised curriculum for undergraduate occupational therapy education in July 2012. University Academic staff and invited practice scholars met together, half yearly for day long meetings to develop and review a new curriculum. The formation of this community of practice allowed for open discourse and feedback to integrate theory and practice. A qualitative study utilised two focus groups, one for academic staff and one for practice scholars, at the end of the third meeting. The focus groups were facilitated by an external researcher, recorded and transcribed verbatim. Thematic analysis elicited five major themes. Participants reported a sense of community and commitment to the curriculum process. Five themes emerged from the focus groups: (i) a sense of community; (ii) a two-way process with mutual benefits; (iii) benefits to the curriculum and to student learning; (iv) future opportunities including resilience of graduates, and potential research collaborations; and (v) the structure and process of engaging in the community of practice. The commitment of time, planning and resources required to establish and participate in collaborative curriculum development with practice scholars is shown to be a valuable investment for occupational therapy academics, expert practice scholars and ultimately for student learning. Further studies of student and graduate outcomes from the curriculum are warranted. Potential future outcomes of this process include resilience in graduates and collaborative research with practice scholars. © 2015 Occupational Therapy Australia.
Kalb, Michael W.; Higgins, Glenn J.; Mahoney, Robert L.; Lutz, Robert; Mauk, Robin; Seablom, Michael; Talabac, Stephen J.
2005-01-01
A recently completed two-year NASA-sponsored study on Advanced Weather Forecasting Technologies envisions that given the opportunity to realize key technological advances over the next quarter century, and with judicious infrastructure and technology investments, it may be possible to significantly extend the skill range of model based weather forecasting via real-time two-way feedbacks between computer forecast models and highly networked, intelligent observing systems (Sensor Webs). Through this linkage, the observing system will have access to information about the present and evolving state of the atmosphere and, most importantly, have the intelligence to act on information about the future states of the atmosphere derived from the forecast model. An ultimate aim is full dynamic situation-driven observing system reconfigurability. The system is conceived to enable operational expression of optimized targeted observing. Ideas are presented on how the entire system might be designed and operated from the perspectives of the underlying science, technology evolution, and system engineering in order to provide the needed coordination between and among space- and ground-based observing and forecast model operations. The greatest challenges lay with the development of the large scale deep infrastructure on which the more advanced proposed forecast system functionality depends.
Busigny, Thomas; de Boissezon, Xavier; Puel, Michèle; Nespoulous, Jean-Luc; Barbeau, Emmanuel J
2015-04-01
This article describes the case of a patient who, following herpes simplex encephalitis (HSE), retained the ability to access rich conceptual semantic information for familiar people whom he was no longer able to name. Moreover, this patient presented the very rare combination of name production and name comprehension deficits for different categories of proper names (persons and acronyms). Indeed, besides his difficulty to retrieve proper names, SL presented a severe deficit in understanding and identifying them. However, he was still able to recognize proper names on familiarity decision, demonstrating that name forms themselves were intact. We interpret SL's deficit as a rare form of two-way lexico-semantic disconnection, in which intact lexical knowledge is disconnected from semantic knowledge and face units. We suggest that this disconnection reflects the role of the left anterior temporal lobe in binding together different types of knowledge and supports the classical convergence-zones framework (e.g., Damasio, 1989) rather than the amodal semantic hub theory (e.g., Patterson, Nestor, & Rogers, 2007).
Andersen, Klaus Ejner
1985-01-01
Guinea pig maximization tests (GPMT) with chlorocresol were performed to ascertain whether the sensitization rate was affected by minor changes in the Freund's complete adjuvant (FCA) emulsion used. Three types of emulsion were evaluated: the oil phase was mixed with propylene glycol, saline with...... to the saline/oil emulsion. Placing of the challenge patches affected the response, as simultaneous chlorocresol challenge on the flank located 2 cm closer to the abdomen than the usual challenge site gave decreased reactions....
Zak, Michail
2008-01-01
A report discusses an algorithm for a new kind of dynamics based on a quantum- classical hybrid-quantum-inspired maximizer. The model is represented by a modified Madelung equation in which the quantum potential is replaced by different, specially chosen 'computational' potential. As a result, the dynamics attains both quantum and classical properties: it preserves superposition and entanglement of random solutions, while allowing one to measure its state variables, using classical methods. Such optimal combination of characteristics is a perfect match for quantum-inspired computing. As an application, an algorithm for global maximum of an arbitrary integrable function is proposed. The idea of the proposed algorithm is very simple: based upon the Quantum-inspired Maximizer (QIM), introduce a positive function to be maximized as the probability density to which the solution is attracted. Then the larger value of this function will have the higher probability to appear. Special attention is paid to simulation of integer programming and NP-complete problems. It is demonstrated that the problem of global maximum of an integrable function can be found in polynomial time by using the proposed quantum- classical hybrid. The result is extended to a constrained maximum with applications to integer programming and TSP (Traveling Salesman Problem).
Li Fan; Wen-Chao Liu; Yan-Jun Zhang; Jun Ren; Bo-Rong Pan; Du-Hu Liu; Yan Chen; Zhao-Cai Yu
2005-01-01
AIM: To compare the effect, adverse events, cost-effectiveness and dose intensity (DI) of oral Xeloda vs calcium folinate (CF)/5-FU combination chemotherapy in patients with advanced gastrointestinal malignancies, both combined with bi-platinu two-way chemotherapy.METHODS: A total of 131 patients were enrolled and randomly selected to receive either oral Xeloda (X group)or CF/5-FU (control group). Oral Xeloda 1 000 mg/m2was administered twice daily from d 1 to 14 in X group,while CF 200 mg/m2 was taken as a 2-h intravenous infusion followed by 5-FU 600 mg/m2 intravenously for 4-6 h on d 1-5 in control group. Cisplatin and oxaliplatin were administered in the same way to both the groups:cisplatin 60-80 mg/m2 by hyperthermic intraperitoneal administration, and oxaliplatin 130 mg/m2 intravenously for 2 h on d 1. All the drugs were recycled every 21 d,with at least two cycles. Pyridoxine 50 mg was given t.i.d.orally for prophylaxis of the hand-foot syndrome (HFS).Then the effect, adverse events, cost-effectiveness and DI of the two groups were evaluated.RESULTS: Hundred and fourteen cases (87.0%) finished more than two chemotherapy cycles. The overall response rate of them was 52.5% (X group) and 42.4% (control group) respectively. Tumor progression time (TTP) was 7.35 mo vs5.95 mo, and 1-year survival rate was 53.1% vs 44.5%. There was a remarkable statistical significance of TTP and 1-year survival between the two groups. The main Xeloda-related adverse events were myelosuppression,gastrointestinal toxicity, neurotoxicity and HFS, which were mild and well tolerable. Therefore, no patients withdrew from the study due to side effects before two chemotherapy cycles were finished. Both groups finished pre-arranged DI and the relative DI was nearly 1.0. The average cost for 1 patient in one cycle was $9 137.35(X group) and $8 961.72 (control group), or US ＄1 100.89in X group and $1 079.73 in control group. To add 1% to the response rate costs $ 161.44 vs $210
Tang, Chengpan; Hu, Xiaogong; Zhou, Shanshi; Guo, Rui; He, Feng; Liu, Li; Zhu, Lingfeng; Li, Xiaojie; Wu, Shan; Zhao, Gang; Yu, Yang; Cao, Yueling
2016-10-01
The Beidou Navigation Satellite System (BDS) manages to estimate simultaneously the orbits and clock offsets of navigation satellites, using code and carrier phase measurements of a regional network within China. The satellite clock offsets are also directly measured with Two-way Satellite Time Frequency Transfer (TWSTFT). Satellite laser ranging (SLR) residuals and comparisons with the precise ephemeris indicate that the radial error of GEO satellites is much larger than that of IGSO and MEO satellites and that the BDS orbit accuracy is worse than GPS. In order to improve the orbit determination accuracy for BDS, a new orbit determination strategy is proposed, in which the satellite clock measurements from TWSTFT are fixed as known values, and only the orbits of the satellites are solved. However, a constant systematic error at the nanosecond level can be found in the clock measurements, which is obtained and then corrected by differencing the clock measurements and the clock estimates from orbit determination. The effectiveness of the new strategy is verified by a GPS regional network orbit determination experiment. With the IGS final clock products fixed, the orbit determination and prediction accuracy for GPS satellites improve by more than 50% and the 12-h prediction User Range Error (URE) is better than 0.12 m. By processing a 25-day of measurement from the BDS regional network, an optimal strategy for the satellite-clock-fixed orbit determination is identified. User Equivalent Ranging Error is reduced by 27.6% for GEO satellites, but no apparent reduction is found for IGSO/MEO satellites. The SLR residuals exhibit reductions by 59% and 32% for IGSO satellites but no reductions for GEO and MEO satellites.
Social group utility maximization
Gong, Xiaowen; Yang, Lei; Zhang, Junshan
2014-01-01
This SpringerBrief explains how to leverage mobile users' social relationships to improve the interactions of mobile devices in mobile networks. It develops a social group utility maximization (SGUM) framework that captures diverse social ties of mobile users and diverse physical coupling of mobile devices. Key topics include random access control, power control, spectrum access, and location privacy.This brief also investigates SGUM-based power control game and random access control game, for which it establishes the socially-aware Nash equilibrium (SNE). It then examines the critical SGUM-b
Brandes, U; Gaertler, M; Goerke, R; Hoefer, M; Nikoloski, Z; Wagner, D
2006-01-01
Several algorithms have been proposed to compute partitions of networks into communities that score high on a graph clustering index called modularity. While publications on these algorithms typically contain experimental evaluations to emphasize the plausibility of results, none of these algorithms has been shown to actually compute optimal partitions. We here settle the unknown complexity status of modularity maximization by showing that the corresponding decision version is NP-complete in the strong sense. As a consequence, any efficient, i.e. polynomial-time, algorithm is only heuristic and yields suboptimal partitions on many instances.
Maximizing without difficulty: A modified maximizing scale and its correlates
Linda Lai
2010-01-01
This article presents several studies that replicate and extend previous research on maximizing. A modified scale for measuring individual maximizing tendency is introduced. The scale has adequate psychometric properties and reflects maximizers' aspirations for high standards and their preference for extensive alternative search, but not the decision difficulty aspect included in several previous studies. Based on this scale, maximizing is positively correlated with optimism, need for cogniti...
Katsafados, Petros; Papadopoulos, Anastasios; Varlas, George; Korres, Gerasimos
2015-04-01
The two-way fully coupled atmosphere-ocean wave system WEW has been recently developed in order to study the factors that contribute to the air-sea interaction processes and feedbacks. The coupled system consists of two components: the atmospheric component which is based on the Workstation Eta non-hydrostatic limited area model and the ocean-wave component which is based on the fourth generation OpenMP (OMP) version of the WAM model. The WEW has been already evaluated in a number of high-impact weather and sea state events where generally a more realistic representation of the momentum exchanges in the ocean wind-wave system has been shown However, the new developed wind-wave parameterization scheme reduces both the near surface wind speed and the significant wave height as a response to the increased aerodynamic drag considered by the atmospheric model over rough sea surfaces. Such behavior is mainly attributed to the surface layer parameterization scheme of the atmospheric component which is based on the Mellor-Yamada-Janjic (MYJ) scheme. It is noted that this scheme has been adjusted to support independent atmospheric simulations. Therefore, we proceed to develop a new hybrid surface layer parameterization based on the MYJ and the Janssen schemes that operate in the atmospheric and ocean wave components of the WEW, respectively. In this case the roughness length depends on the wave age instead of the Charnock parameter following the formulation proposed by Vickers and Mahrt. The spatial variability of the wave age is estimated at each ocean wave component time step and it is directly provided to the MYJ scheme. The parameterization of the viscous sublayer and the universal functions for the estimation of the near surface wind speed have been also revised accordingly. In this study, a test version of the new hybrid scheme of WEW has been statistically evaluated against a number of buoys and satellite retrievals over the Mediterranean Sea in a case study of high
Polyploidy Induction of Pteroceltis tatarinowii Maxim
Lin ZHANG; Feng WANG; Zhongkui SUN; Cuicui ZHU; Rongwei CHEN
2015-01-01
3%Objective] This study was conducted to obtain tetraploid Pteroceltis tatari-nowi Maxim. with excel ent ornamental traits. [Method] The stem apex growing points of Pteroceltis tatarinowi Maxim. were treated with different concentrations of colchicine solution for different hours to figure out a proper method and obtain poly-ploids. [Result] The most effective induction was obtained by treatment with 0.6%-0.8% colchicine for 72 h with 34.2% mutation rate. Flow cytometry and chromosome observation of the stem apex growing point of P. tatarinowi Maxim. proved that the tetraploid plants were successful y obtained with chromosome number 2n=4x=36. [Conclusion] The result not only fil s the blank of polyploid breeding of P. tatarinowi , but also provides an effective way to broaden the methods of cultivation of fast-growing, high-quality, disease-resilience, new varieties of Pteroceltis.
HEMI: Hyperedge Majority Influence Maximization
Gangal, Varun; Narayanam, Ramasuri
2016-01-01
In this work, we consider the problem of influence maximization on a hypergraph. We first extend the Independent Cascade (IC) model to hypergraphs, and prove that the traditional influence maximization problem remains submodular. We then present a variant of the influence maximization problem (HEMI) where one seeks to maximize the number of hyperedges, a majority of whose nodes are influenced. We prove that HEMI is non-submodular under the diffusion model proposed.
Andersen, Klaus Ejner
1985-01-01
Guinea pig maximization tests (GPMT) with chlorocresol were performed to ascertain whether the sensitization rate was affected by minor changes in the Freund's complete adjuvant (FCA) emulsion used. Three types of emulsion were evaluated: the oil phase was mixed with propylene glycol, saline...... with 30% (v/v) ethanol or saline, respectively. Relative viscosity was used as one measure of physical properties of the emulsion. Higher degrees of sensitization (but not rates) were obtained at the 48 h challenge reading with the oil/propylene glycol and oil/saline + ethanol emulsions compared...... to the saline/oil emulsion. Placing of the challenge patches affected the response, as simultaneous chlorocresol challenge on the flank located 2 cm closer to the abdomen than the usual challenge site gave decreased reactions....
Numerical Analysis of Two-Way Interaction between Weld-Pool and Arc for GTA Welding Process
无
2001-01-01
A mathematical model to describe the heat transfer and fluid flow in the mutually coupled weld pool and arc by an interactive free surface of the pool for a stationary gas tungsten arc welding (GTAW) is developed. The two sets of governing equations and auxiliary formulas, controlling the weld pool and plasma arc systems respectively, were solved by a finite difference method. A boundary-fitted coordinate system was adopted because the free surface has a curved and unknown shape during welding. The results of this work provide a fundamental basis for predicting the behavior of an integrated weld pool and arc system from first principles.
MAXIMS VIOLATIONS IN LITERARY WORK
Widya Hanum Sari Pertiwi
2015-12-01
Full Text Available This study was qualitative research action that focuses to find out the flouting of Gricean maxims and the functions of the flouting in the tales which are included in collection of children literature entitled My Giant Treasury of Stories and Rhymes. The objective of the study is generally to identify the violation of maxims of quantity, quality, relevance, and manner in the data sources and also to analyze the use of the flouting in the tales which are included in the book. Qualitative design using categorizing strategies, specifically coding strategy, was applied. Thus, the researcher as the instrument in this investigation was selecting the tales, reading them, and gathering every item which reflects the violation of Gricean maxims based on some conditions of flouting maxims. On the basis of the data analysis, it was found that the some utterances in the tales, both narration and conversation, flouting the four maxims of conversation, namely maxim of quality, maxim of quantity, maxim of relevance, and maxim of manner. The researcher has also found that the flouting of maxims has one basic function that is to encourage the readers’ imagination toward the tales. This one basic function is developed by six others functions: (1 generating specific situation, (2 developing the plot, (3 enlivening the characters’ utterance, (4 implicating message, (5 indirectly characterizing characters, and (6 creating ambiguous setting. Keywords: children literature, tales, flouting maxims
Swanepoel, Konrad J
2011-01-01
A subset of a normed space X is called equilateral if the distance between any two points is the same. Let m(X) be the smallest possible size of an equilateral subset of X maximal with respect to inclusion. We first observe that Petty's construction of a d-dimensional X of any finite dimension d >= 4 with m(X)=4 can be generalised to show that m(X\\oplus_1\\R)=4 for any X of dimension at least 2 which has a smooth point on its unit sphere. By a construction involving Hadamard matrices we then show that both m(\\ell_p) and m(\\ell_p^d) are finite and bounded above by a function of p, for all 1 1 such that m(X) <= d+1 for all d-dimensional X with Banach-Mazur distance less than c from \\ell_p^d. Using Brouwer's fixed-point theorem we show that m(X) <= d+1 for all d-\\dimensional X with Banach-Mazur distance less than 3/2 from \\ell_\\infty^d. A graph-theoretical argument furthermore shows that m(\\ell_\\infty^d)=d+1. The above results lead us to conjecture that m(X) <= 1+\\dim X.
Unified Maximally Natural Supersymmetry
Huang, Junwu
2016-01-01
Maximally Natural Supersymmetry, an unusual weak-scale supersymmetric extension of the Standard Model based upon the inherently higher-dimensional mechanism of Scherk-Schwarz supersymmetry breaking (SSSB), possesses remarkably good fine tuning given present LHC limits. Here we construct a version with precision $SU(2)_{\\rm L} \\times U(1)_{\\rm Y} $ unification: $\\sin^2 \\theta_W(M_Z) \\simeq 0.231$ is predicted to $\\pm 2\\%$ by unifying $SU(2)_{\\rm L} \\times U(1)_{\\rm Y} $ into a 5D $SU(3)_{\\rm EW}$ theory at a Kaluza-Klein scale of $1/R_5 \\sim 4.4\\,{\\rm TeV}$, where SSSB is simultaneously realised. Full unification with $SU(3)_{\\rm C}$ is accommodated by extending the 5D theory to a $N=4$ supersymmetric $SU(6)$ gauge theory on a 6D rectangular orbifold at $1/R_6 \\sim 40 \\,{\\rm TeV}$. TeV-scale states beyond the SM include exotic charged fermions implied by $SU(3)_{\\rm EW}$ with masses lighter than $\\sim 1.2\\,{\\rm TeV}$, and squarks in the mass range $1.4\\,{\\rm TeV} - 2.3\\,{\\rm TeV}$, providing distinct signature...
Nemani, Ravi Dakshina Murthy; Rao, M. V. S.; Grandhe, Veera Venkata Satya Naranyana
2016-09-01
The present work is an effort to quantify the punching shear load resistance effect on two way simply supported slab specimens with replacement of cement by Ground Granulated Blast Furnace Slag (GGBS) with different edge conditions at various replacement levels and evaluate its efficiency. GGBS replacement has emerged as a major alternative to conventional concrete and has rapidly drawn the concrete industry attention due to its cement savings, cost savings, environmental and socio-economic benefits. The two way slab specimens were subjected to punching shear load by in house fabricated apparatus. The slab specimens were cast using M30 grade concrete with HYSD bars. The cement was partially replaced with GGBS at different percentages i.e., 0 to 30 % at regular intervals of 10 %. The test results indicate that the two way slab specimens with partial replacement of cement by GGBS exhibit high resistance against punching shear when compared with conventional concretes slab specimens.
无
2001-01-01
The effect of thermal cycling under loading on martensitictransformation and two-way shape memory effect was investigated for Ti-49.8 at. pct Ni alloy. It is shown that Ms and Mf temperature increase with increasing the number of cycles, while As and Af temperature decrease during thermal cycling. The total strain εt and permanent strain εp increase with increasing applied stress and number of cycles. The two-way shape memory effect can be improved by proper thermal cycling training under loading, while excessively high applied stress results in the deterioration of TWSME. The reason for the changes in martensitic transformation characteristics and two-way shape memory effect during thermal cycling under loading is discussed based on the analysis of microstructure by TEM observations.
E. N. Saburov
2014-01-01
Full Text Available The heat dissipation on the lateral surface of the cyclone chamber working volume with asymmetrical input and output of gases is considered in the present paper in contrast to the previously executed [1–10]. The relative values of input gas flow and the relative diameters of the outlet are different in each of the halves of the working volume. The heat dissipation by convection to the swirling airflow was studied by the method of variation of the aggregate state of the heating agent – water vapor slightly superheated (at 2–3 °С condensation. Collecting the condensate produced from the work site through a water lock, providing maintaining of constant pressure in the calorimeter. The quantity of heat transmitted during the experiment was determined by the amount of collected condensate.In the experiments on the camera with two-sided asymmetric output relative gas outlet diameter on one side of the camera varied Relative diameter of the outlet on the other hand remained constant. In the experiences on the camera with the bilateral asymmetrical conditions for the introduction of gases the asymmetry of the introduction of flow was created due to a change in the relative entrance area whoo remained constant. Local heat transfer coefficient was determined for different values dimensionless longitudinal coordinate coinciding with the axis of the chamber, directed toward the outlet, measured from the middle section of the working volume. Еquations for calculation of heat transfer coefficients on the lateral surface of the howling cyclone chambers with unbalanced input and output gases, оbtained in this paper, give the satisfactory agreement of the calculated and experimental data that allows to recommend to their practical application.
Xianglong MENG; Wei CAI; K.T. LAU; L.M. ZHOU; Liancheng ZHAO
2003-01-01
The Effect of the thermal cycling training under constant strain on the two-way shape memory effect (TWSME) in a Ti36Ni49Hf15 high temperature shape memory alloy (SMA) has been investigated by bending tests. The results indicated that the training procedure is beneficial to get the better TWSME. The two-way shape memory strain increases with increasing the training strain. And it decreases with increasing the training temperature. The TWSME obtained in the present alloy shows poorer stability compared with that obtained in the TiNi alloys.
Rangel, M. Gudelia; Martinez-Donate, Ana P.; Hovell, Melbourne; Sipan, Carol L.; Zellner, Jennifer A.; Gonzalez-Fagoaga, Eduardo; Kelley, Norma J.; Asadi-Gonzalez, Ahmed; Amuedo-Dorantes, Catalina; Magis-Rodriguez, Carlos
2012-01-01
A large number of Mexican migrants are deported to Mexico and released in the North Mexican border region every year. Despite their volume and high vulnerability, little is known about the level of HIV infection and related risk behaviors among this hard-to-reach population. We conducted a cross-sectional, probability survey with deported Mexican migrants in Tijuana, Mexico (N=693) and estimated levels of HIV infection and behavioral risk factors among this migrant flow. The sample and population estimated rates of HIV for deported males were 1.23% and 0.80%, respectively. No positive cases were found among the female sample. We found high lifetime rates of reported sexually transmitted infections (22.3%) and last 12-months rates of unprotected sex (63.0%), sex with multiple sexual partners (18.1%), casual partners (25.7%), and sex workers (8.6%), compared to U.S. and Mexico adults. HIV prevention, testing, and treatment programs for this large, vulnerable, and transnational population need to be implemented in both the U.S. and Mexico. PMID:22562390
双向旋流污水净化器处理溢流污水%Treatment of overflow using two-way cyclone flocculation hydrocyclone
臧宝凤; 黄勇强; 徐明力; 史凯; 朱艳
2013-01-01
The structure characteristics and the operating mechanism of two-way cyclone flocculation hydrocy-clone were introduced. The two cyclone chambers and filtration layer improved the purification efficiency of hydrocy-clone. The separation performance and the operation stability of the new device were evaluated by processing the CSOs. Results show that the hydrocyclone got a successful removal effect under the condition of PAC of 150 mg/L, flow rate of 1.5 m3/h.HRT of 10 min.the removal rates of COD,SS,TN,TP are 70.0% ,97.7% ,71.2% and 78.6% , respectively. And the removal rates of COD and SS are 65% and 96% , respectively after the device has run for 3 h.%介绍了双向旋流絮凝沉淀一体化污水净化器的结构特点及运行机理,其具有双旋流室和悬浮过滤层的结构提高了对污水的净化效率.利用双向旋流净化器对镇江市溢流污水进行处理,对装置的分离性能和运行的稳定性进行了研究,实验结果表明,双向旋流器在絮凝剂PAC投加量为150 mg/L,入口流量在1.5 m3/h,水力停留时间为10 min条件下对溢流污水的处理效果较好,COD、SS、TN和TP的去除率分别为70.0％、97.7％、71.2％和78.6％.装置连续运行3h对COD和SS的平均去除率分别在65％和96％以上.
Maximal subgroups of finite groups
S. Srinivasan
1990-01-01
Full Text Available In finite groups maximal subgroups play a very important role. Results in the literature show that if the maximal subgroup has a very small index in the whole group then it influences the structure of the group itself. In this paper we study the case when the index of the maximal subgroups of the groups have a special type of relation with the Fitting subgroup of the group.
Finding Maximal Quasiperiodicities in Strings
Brodal, Gerth Stølting; Pedersen, Christian N. S.
2000-01-01
of length n in time O(n log n) and space O(n). Our algorithm uses the suffix tree as the fundamental data structure combined with efficient methods for merging and performing multiple searches in search trees. Besides finding all maximal quasiperiodic substrings, our algorithm also marks the nodes......Apostolico and Ehrenfeucht defined the notion of a maximal quasiperiodic substring and gave an algorithm that finds all maximal quasiperiodic substrings in a string of length n in time O(n log2 n). In this paper we give an algorithm that finds all maximal quasiperiodic substrings in a string...
Maximizing Entropy over Markov Processes
Biondi, Fabrizio; Legay, Axel; Nielsen, Bo Friis
2013-01-01
computation reduces to finding a model of a specification with highest entropy. Entropy maximization for probabilistic process specifications has not been studied before, even though it is well known in Bayesian inference for discrete distributions. We give a characterization of global entropy of a process...... as a reward function, a polynomial algorithm to verify the existence of an system maximizing entropy among those respecting a specification, a procedure for the maximization of reward functions over Interval Markov Chains and its application to synthesize an implementation maximizing entropy. We show how...
Maximizing entropy over Markov processes
Biondi, Fabrizio; Legay, Axel; Nielsen, Bo Friis
2014-01-01
computation reduces to finding a model of a specification with highest entropy. Entropy maximization for probabilistic process specifications has not been studied before, even though it is well known in Bayesian inference for discrete distributions. We give a characterization of global entropy of a process...... as a reward function, a polynomial algorithm to verify the existence of a system maximizing entropy among those respecting a specification, a procedure for the maximization of reward functions over Interval Markov Chains and its application to synthesize an implementation maximizing entropy. We show how...
Gort, Mileidis
2008-01-01
This study analyzes the nature of spontaneous bilingual peer interactions across Spanish/English integrated learning contexts, as well as the roles played by Spanish-dominant and English-dominant peers in mediating each others' bilingual, biliteracy, and cross-cultural learning in a two-way partial immersion (TWpI) program. Implications for…
Kabat, Ellen J.; Friedel, Janice Nahra
Both formative and summative evaluations of the operation of the Eastern Iowa Community College District's (EICCD) Televised Interactive Education (TIE) System were conducted. The TIE system links three Iowa community colleges and local public and private universities via two-way microwave connections, allowing the production and transmittal of…
Montanari, Simona; Simón-Cereijido, Gabriela; Hartel, Antonella
2016-01-01
This study examines the writing skills of students in grades 1 to 5 of an Italian-English two-way immersion program. Narrative writing samples were collected in both languages and scored for content, organization, grammar, mechanics, vocabulary, text length, and overall total score. The results show that writing skills improved as a function of…
Peters, W.; Krol, M. C.; Dlugokencky, E. J.; Dentener, F. J.; Bergamaschi, P.; Dutton, G.; Velthoven, P. V.; Miller, J. B.; Bruhwiler, L.; Tans, P. P.
2004-01-01
We present an evaluation of transport of sulfur hexafluoride (SF6) in the two-way nested chemistry-transport model "Tracer Model 5" (TM5). Modeled SF6 values for January 2000 to November 2003 are compared with NOAA CMDL observations. This includes new high-frequency SF6 observations, frequent
Reinhart, Julie; Schneider, Paul
2001-01-01
This study sought to develop assessment tools to measure students' perceptions of two-way audio/video distance classrooms, as well as self-efficacy and satisfaction with distance learning experience. These measures were subsequently used to assess the relationship between these variables. Findings offer two possible indications. Students do not…
Palmer, Deborah K.
2009-01-01
Two-way bilingual immersion education, offered in a fast-growing number of primary schools in the United States, provides primary language maintenance to minority language speakers while simultaneously offering an enrichment "foreign" language immersion experience to English-speaking children in the same classroom, generally with the same teacher.…
Neugebauer, Sabina R.; Howard, Elizabeth R.
2015-01-01
The current study, with 409 fourth graders in two-way immersion programs, explored the writing self-perceptions of native English and native Spanish speakers and the relationship between self-perceptions and writing performance. An adapted version of the Writer Self-Perception Scale (WSPS) was administered along with a writing task. Native English…
Neugebauer, Sabina R.; Howard, Elizabeth R.
2015-01-01
The current study, with 409 fourth graders in two-way immersion programs, explored the writing self-perceptions of native English and native Spanish speakers and the relationship between self-perceptions and writing performance. An adapted version of the Writer Self-Perception Scale (WSPS) was administered along with a writing task. Native English…
Nascimento, Frank C.
2012-01-01
The current pilot study compares the overall academic achievement in the area of language arts literacy among elementary bilingual students enrolled in either a Dual Language: Two-Way Immersion program or in an Early Exit, Transitional Bilingual program in a large urban public school district. By analyzing the results of curriculum based measures…
Reyes, Sharon Adelman; Vallone, Trina Lynn
2007-01-01
This literature review will take a focused look at the three currently accepted theoretical foundations upon which two-way bilingual immersion programs are based. Through an examination of research on identity construction in childhood and adolescence, particularly as seen through a critical pedagogical lens, it proposes that there exists a fourth…
Bae, Jungok; Bachman, Lyle F.
1998-01-01
A study investigated the factorial distinctiveness of two receptive language skills, listening and reading, and the equivalence of factor structure across two groups. Subjects were 156 students, Korean-Americans and non-Korean-Americans, in grades two through four in a two-way bilingual education program. Students were tested in listening and…
Montanari, Simona; Simón-Cereijido, Gabriela; Hartel, Antonella
2016-01-01
This study examines the writing skills of students in grades 1 to 5 of an Italian-English two-way immersion program. Narrative writing samples were collected in both languages and scored for content, organization, grammar, mechanics, vocabulary, text length, and overall total score. The results show that writing skills improved as a function of…
李明东; 储金获; 奚汉达; 马培荪; 郝颖明
2000-01-01
In this paper the work mechainism of the Bias Two Way SMA Actuator is investigated,the quantitative relationship of the output force,output displacement and load of the actuator and the elastic stiffness and predeformation of the driving component is constructed.Based on the basic law of thermodynamics,the periodical flowing,conveying,and transformation model of the energy in the work process of the Bias Two Way SMA Actuator is constructed.The paper indicated that,the round voyage energy of the Bias Two Way SMA Actuator all come from the elastic potential energy of the SMA component initialed by phase fransformation.Part of the energy does work at come stroke,part is conveyed to thebias component,they do work at return stroke,another is released.%研究了偏动式双程SMA驱动器的工作机理，建立了驱动器输出力、输出位移、负载与驱动元件弹性刚度和预变形之间的变量关系。基于热力学基本定律，给出了双程SMA驱动器工作过程中能量的周期性流动、转移和转化模型，指出双程SMA驱动器双程做功的能量都来源于SMA元件的相变弹性势能，能量的一部分用于来程做功，一部分在来程转移给偏置元件，用于回程时做工，还有一部分被释放掉。
Kireeva, I. V.; Platonova, Yu. N.; Chumlyakov, Yu. I.
2017-02-01
The ordinary and two-way shape memory effects (SMEs) are investigated for [ overline{1} 12] single crystals of Ti-51.3Ni (at.%) alloy aged at 823 K for 1.5 h in free state and under tensile stress of 150 MPa without hydrogen and after saturation by hydrogen. It is established that without hydrogen in [ overline{1} 12] single crystals with one and four variants of Ti3Ni4 particles the maximum magnitude of the ordinary SME is 1.9-2.6% under the external stress σext = 250 MPa. Under σext > 250 MPa, crystals are destroyed. The magnitude of the two-way SME caused by the B2- R- B19' MT equal to 1.1% at σext = 0 is observed in [ overline{1} 12] single crystals with one variant of Ti3Ni4 particles. The physical reason for the observed two-way SME is the internal compressive stresses oriented along the [ overline{1} 12] directions arising from one variant of Ti3Ni4 particles as a result of aging under tensile stress of 150 MPa. It is established that hydrogen does not influence the TR temperature, reduces the plasticity, and suppresses the two-way SME. The suppression of two-way SME in the [ overline{1} 12] single crystals of the Ti-51.3Ni (at.%) alloy with one variant of Ti3Ni4 particles is caused by shielding of stress fields from one variant of Ti3Ni4 particles and multiple nucleation of R- and B19' martensite variants under loading with saturation by hydrogen.
Gonzalez-Sanchez, Jon
2010-01-01
Let $w = w(x_1,..., x_n)$ be a word, i.e. an element of the free group $F =$ on $n$ generators $x_1,..., x_n$. The verbal subgroup $w(G)$ of a group $G$ is the subgroup generated by the set $\\{w (g_1,...,g_n)^{\\pm 1} | g_i \\in G, 1\\leq i\\leq n \\}$ of all $w$-values in $G$. We say that a (finite) group $G$ is $w$-maximal if $|G:w(G)|> |H:w(H)|$ for all proper subgroups $H$ of $G$ and that $G$ is hereditarily $w$-maximal if every subgroup of $G$ is $w$-maximal. In this text we study $w$-maximal and hereditarily $w$-maximal (finite) groups.
Consistent 4-form fluxes for maximal supergravity
Godazgar, Hadi; Krueger, Olaf; Nicolai, Hermann
2015-01-01
We derive new ansaetze for the 4-form field strength of D=11 supergravity corresponding to uplifts of four-dimensional maximal gauged supergravity. In particular, the ansaetze directly yield the components of the 4-form field strength in terms of the scalars and vectors of the four-dimensional maximal gauged supergravity---in this way they provide an explicit uplift of all four-dimensional consistent truncations of D=11 supergravity. The new ansaetze provide a substantially simpler method for uplifting d=4 flows compared to the previously available method using the 3-form and 6-form potential ansaetze. The ansatz for the Freund-Rubin term allows us to conjecture a `master formula' for the latter in terms of the scalar potential of d=4 gauged supergravity and its first derivative. We also resolve a long-standing puzzle concerning the antisymmetry of the flux obtained from uplift ansaetze.
Maximizing without difficulty: A modified maximizing scale and its correlates
Lai, Linda
2010-01-01
... included in several previous studies. Based on this scale, maximizing is positively correlated with optimism, need for cognition, desire for consistency, risk aversion, intrinsic motivation, self-efficacy and perceived workload, whereas...
Maximizing and customer loyalty: Are maximizers less loyal?
Linda Lai
2011-06-01
Full Text Available Despite their efforts to choose the best of all available solutions, maximizers seem to be more inclined than satisficers to regret their choices and to experience post-decisional dissonance. Maximizers may therefore be expected to change their decisions more frequently and hence exhibit lower customer loyalty to providers of products and services compared to satisficers. Findings from the study reported here (N = 1978 support this prediction. Maximizers reported significantly higher intentions to switch to another service provider (television provider than satisficers. Maximizers' intentions to switch appear to be intensified and mediated by higher proneness to regret, increased desire to discuss relevant choices with others, higher levels of perceived knowledge of alternatives, and higher ego involvement in the end product, compared to satisficers. Opportunities for future research are suggested.
Are maximizers really unhappy? The measurement of maximizing tendency,
Dalia L. Diab
2008-06-01
Full Text Available Recent research suggesting that people who maximize are less happy than those who satisfice has received considerable fanfare. The current study investigates whether this conclusion reflects the construct itself or rather how it is measured. We developed an alternative measure of maximizing tendency that is theory-based, has good psychometric properties, and predicts behavioral outcomes. In contrast to the existing maximization measure, our new measure did not correlate with life (dissatisfaction, nor with most maladaptive personality and decision-making traits. We conclude that the interpretation of maximizers as unhappy may be due to poor measurement of the construct. We present a more reliable and valid measure for future researchers to use.
Principles of maximally classical and maximally realistic quantum mechanics
S M Roy
2002-08-01
Recently Auberson, Mahoux, Roy and Singh have proved a long standing conjecture of Roy and Singh: In 2-dimensional phase space, a maximally realistic quantum mechanics can have quantum probabilities of no more than + 1 complete commuting cets (CCS) of observables coexisting as marginals of one positive phase space density. Here I formulate a stationary principle which gives a nonperturbative deﬁnition of a maximally classical as well as maximally realistic phase space density. I show that the maximally classical trajectories are in fact exactly classical in the simple examples of coherent states and bound states of an oscillator and Gaussian free particle states. In contrast, it is known that the de Broglie–Bohm realistic theory gives highly nonclassical trajectories.
Li, Chung-Yi; Lu, Hai-Han; Ying, Cheng-Ling; Zheng, Jun-Ren; Lin, Che-Yu; Wan, Zhi-Wei
2015-02-23
A two-way fiber-wireless convergence system based on a two-stage injection-locked 1.55-μm vertical-cavity surface-emitting lasers (VCSELs) transmitter and an optical interleaver (IL) to deliver intensity-modulated and phase-remodulated millimeter-wave (MMW) data signals over a 40-km single-mode fiber (SMF) and a 5-m radio frequency (RF) wireless transport is proposed and experimentally demonstrated. Bit error rate (BER) and eye diagram perform brilliantly through a serious investigation in systems. Such a two-way fiber-wireless convergence system is a promising option, it reveals a prominent one to present its advancement in integration of distribute fiber and in-house network.
Datta, Subimal; Siwek, Donald F.; Huang, Max P.
2009-01-01
Previous studies have shown that two-way active avoidance (TWAA) memory processing involves a functional interaction between the pontine wave (P wave) generator and the CA3 region of the dorsal hippocampus (DH-CA3). The present experiments examined whether the interaction between P wave generator activity and the DH-CA3 involves the intracellular protein kinase A (PKA) signaling system. In the first series of experiments, rats were subjected to a session of TWAA training followed immediately ...
Maximizing ROI with yield management
Neil Snyder
2001-01-01
.... the technology is based on the concept of yield management, which aims to sell the right product to the right customer at the right price and the right time therefore maximizing revenue, or yield...
Are CEOs Expected Utility Maximizers?
John List; Charles Mason
2009-01-01
Are individuals expected utility maximizers? This question represents much more than academic curiosity. In a normative sense, at stake are the fundamental underpinnings of the bulk of the last half-century's models of choice under uncertainty. From a positive perspective, the ubiquitous use of benefit-cost analysis across government agencies renders the expected utility maximization paradigm literally the only game in town. In this study, we advance the literature by exploring CEO's preferen...
Gaussian maximally multipartite entangled states
Facchi, Paolo; Lupo, Cosmo; Mancini, Stefano; Pascazio, Saverio
2009-01-01
We introduce the notion of maximally multipartite entangled states (MMES) in the context of Gaussian continuous variable quantum systems. These are bosonic multipartite states that are maximally entangled over all possible bipartitions of the system. By considering multimode Gaussian states with constrained energy, we show that perfect MMESs, which exhibit the maximum amount of bipartite entanglement for all bipartitions, only exist for systems containing n=2 or 3 modes. We further numerically investigate the structure of MMESs and their frustration for n <= 7.
All maximally entangling unitary operators
Cohen, Scott M. [Department of Physics, Duquesne University, Pittsburgh, Pennsylvania 15282 (United States); Department of Physics, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213 (United States)
2011-11-15
We characterize all maximally entangling bipartite unitary operators, acting on systems A and B of arbitrary finite dimensions d{sub A}{<=}d{sub B}, when ancillary systems are available to both parties. Several useful and interesting consequences of this characterization are discussed, including an understanding of why the entangling and disentangling capacities of a given (maximally entangling) unitary can differ and a proof that these capacities must be equal when d{sub A}=d{sub B}.
Salvio, Alberto; Strumia, Alessandro; Urbano, Alfredo
2016-01-01
Motivated by the 750 GeV diphoton excess found at LHC, we compute the maximal width into $\\gamma\\gamma$ that a neutral scalar can acquire through a loop of charged fermions or scalars as function of the maximal scale at which the theory holds, taking into account vacuum (meta)stability bounds. We show how an extra gauge symmetry can qualitatively weaken such bounds, and explore collider probes and connections with Dark Matter.
Sanger, George F.
1994-01-01
Safety-tether device enables crewmembers on spacecraft to retrieve crewmember drifting away from spacecraft. Alternatively, drifting crewmember who carries device uses it to grasp and return to spacecraft. Also used on Earth. For example, rescuer on vessel or pier uses it to retrieve and haul drowning or unconscious person to safety; drifting person or rescuer in water uses it to grasp and hold onto support.
Two ways to support reflexivity
Adriansen, Hanne Kirstine; Knudsen, Hanne
2013-01-01
Management (MEM). MEM provides the participating managers with a new language that can give them a critical distance to the overload of expectations they meet at work and MEM teaches the participants to translate this new language into practice. The pedagogy used for this is labelled ‘experimental management......’. This requires participants to conduct experiments in their own organization, to reflect on and analyse their experiences with concepts from the curriculum. While the new language and the experimental teaching format are difficult, the participants learn a reflexive practice that can enable them to life up...
Y.-Y. Yan
2014-07-01
Full Text Available Global chemical transport models (CTMs are used extensively to study air pollution and transport at a global scale. These models are limited by coarse horizontal resolutions, not allowing for detailed representation of small-scale nonlinear processes over the pollutant source regions. Here we couple the global GEOS-Chem CTM and its three high-resolution nested models to simulate the tropospheric carbon monoxide (CO over the Pacific Ocean during five HIAPER Pole-to-Pole Observations (HIPPO campaigns between 2009 and 2011. We develop a two-way coupler, PKUCPL, to integrate simulation results for chemical constituents from the global model (at 2.5° long. × 2° lat. and the three nested models (at 0.667° long. × 0.5° lat. covering Asia, North America and Europe, respectively. The coupler obtains nested model results to modify the global model simulation within the respective nested domains, and simultaneously acquires global model results to provide lateral boundary conditions for the nested models. Compared to the global model alone, the two-way coupled simulation results in enhanced CO concentrations in the nested domains. Sensitivity tests suggest the enhancement to be a result of improved representation of the spatial distributions of CO, nitrogen oxides and non-methane volatile organic compounds, the meteorological dependence of natural emissions, and other resolution-dependent processes. The relatively long lifetime of CO allows for the enhancement to be accumulated and carried across the globe. We find that the two-way coupled simulation increases the global tropospheric mean CO concentrations in 2009 by 10.4%, with a greater enhancement at 13.3% in the Northern Hemisphere. Coincidently, the global tropospheric mean hydroxyl radical (OH is reduced by 4.2% (as compared to the interannual variability of OH at 2.3%, resulting in a 4.2% enhancement in the methyl chloroform lifetime (MCF, via reaction with tropospheric OH. The resulting CO
A. Garmroodi Asil
2017-09-01
To further reduce the sulfur dioxide emission of the entire refining process, two scenarios of acid gas or air preheats are investigated when either of them is used simultaneously with the third enrichment scheme. The maximum overall sulfur recovery efficiency and highest combustion chamber temperature is slightly higher for acid gas preheats but air preheat is more favorable because it is more benign. To the best of our knowledge, optimization of the entire GTU + enrichment section and SRU processes has not been addressed previously.
Zhang, Mengliang; Harrington, Peter de B
2013-12-15
Seven polychlorinated biphenyls (PCBs) commercial mixtures, Aroclor 1016, 1221, 1232, 1242, 1248, 1254, and 1260, were analyzed by gas chromatography/mass spectrometry (GC/MS) combined with solid phase microextraction (SPME). Three pattern recognition methods: a fuzzy rule-building expert system (FuRES), partial least-squares discriminant analysis (PLS-DA), and a fuzzy optimal associative memory (FOAM) were used to build classification models. Modulo compression was introduced for data preprocessing to extract the characteristic features and compress the data size. Baseline correction and data normalization were also applied prior to data processing. Four GC/MS data set configurations were constructed and used to evaluate the classifiers and data pretreatments including two-way modulo compressed, two-way data, one-way total ion current and one-way total mass spectrum. The results indicate that modulo compression and baseline correction methods significantly improved the performance of the classifiers which resulted in improved classification rates for FuRES, PLS-DA, and FOAM classifiers. By using two-way modulo compressed data sets, the average classification rates with FuRES, PLS-DA, and FOAM were 100±0%, 94.6±0.7%, and 96.1±0.6% for 100 bootstrapped Latin partitions of the Aroclor standards. The classifiers were validated by application to Aroclor samples extracted from soil with no parametric changes except that the calibration set of standards and validation set of soil samples were individually mean centered. The classification rates for the GC/MS modulo 35 compressed data obtained from the Aroclor soil samples with FOAM, FuRES, and PLS-DA were 100%, 96.4%, and 78.6%, respectively. Therefore, a chemometric pipeline for SPME-GC/MS data coupled with chemometric analysis was devised as a fast authentication method for different Aroclors in soil. © 2013 Published by Elsevier B.V.
数字电视接入网双向改造方案%Two-way Reform Scheme of Digital TV Access Network
邵永泽
2015-01-01
随着数字电视双向业务的推进，需要对接入网进行双向改造，应本着“光进铜退”的原则，光缆线路应一次规划，分步实施。接入网不仅要进行光缆改造，还要对同轴电缆网进行改造，既要充分利旧，又要兼顾未来发展，便于平滑升级，光缆线路要留有冗余，为光纤进一步向用户靠近、不断提高双向用户的入户带宽打下基础。%With the development of digital TV two-way business,it need to access network for two-way trans-formation,Should be based on the principle of “light into copper retreat”,Fiber optic cable line should be a plan,Step by step implementation.Access network is not only to carry out optical fiber cable,Also to the co-axial cable network to transform,Not only to make full use of the old,To take into account the future develop-ment,Easy to smooth upgrade,Fiber optic cable line to stay redundant,For the fiber further to the user,and continuously improve the home bandwidth of two-way users to lay the foundation.
Algebraic curves of maximal cyclicity
Caubergh, Magdalena; Dumortier, Freddy
2006-01-01
The paper deals with analytic families of planar vector fields, studying methods to detect the cyclicity of a non-isolated closed orbit, i.e. the maximum number of limit cycles that can locally bifurcate from it. It is known that this multi-parameter problem can be reduced to a single-parameter one, in the sense that there exist analytic curves in parameter space along which the maximal cyclicity can be attained. In that case one speaks about a maximal cyclicity curve (mcc) in case only the number is considered and of a maximal multiplicity curve (mmc) in case the multiplicity is also taken into account. In view of obtaining efficient algorithms for detecting the cyclicity, we investigate whether such mcc or mmc can be algebraic or even linear depending on certain general properties of the families or of their associated Bautin ideal. In any case by well chosen examples we show that prudence is appropriate.
BOUNDEDNESS OF MAXIMAL SINGULAR INTEGRALS
CHEN JIECHENG; ZHU XIANGRONG
2005-01-01
The authors study the singular integrals under the Hormander condition and the measure not satisfying the doubling condition. At first, if the corresponding singular integral is bounded from L2 to itseff, it is proved that the maximal singu lar integral is bounded from L∞ to RBMO except that it is infinite μ-a.e. on Rd. A sufficient condition and a necessary condition such that the maximal singular integral is bounded from L2 to itself are also obtained. There is a small gap between the two conditions.
Analysis of the influential factors of maximal-effort expiratory capacity of elderly women.
Lee, Bomjin; Park, Soyun; Han, Dongwook
2016-10-01
[Purpose] The purpose of this study was to find the influential factors of maximal-effort expiratory capacity of elderly women. [Subjects and Methods] The subjects of this study were 83 healthy elderly women. The study's methods and purpose were explained and these women agreed to participate. The maximal-effort expiratory capacity was measured using spirometry (Pony FX, COSMED Inc., Italy). We measured forced vital capacity, forced expiratory volume in 1 second, forced expiratory volume in 1 second/forced vital capacity, maximal expiratory flow 75%, maximal expiratory flow 50%, and maximal expiratory flow 25%. [Results] Regarding forced vital capacity and forced expiratory volume in 1 second, it was found that height and age were influential factors. Regarding forced expiratory volume in 1 second/forced vital capacity %, maximal expiratory flow 75%, maximal expiratory flow 50%, and maximal expiratory flow 25%, it was found that only age was an influential factor. [Conclusion] This study demonstrated that the most influential factors of maximal-effort expiratory capacity of elderly women were age, and the second influential factor was height. We noticed that weight was the least influential factor among them.
Research about EPON two-way authenticated encryption scheme based on the MAC%基于MAC层的EPON双向认证加密方案研究
邹丹; 张跃进
2012-01-01
Analyzed on the basis of the EPON network security risks that exist in the EPON network security issues, according to the two-way authenticated encryption scheme and the technology roadmap proposed two-way authentication scheme of an anti-MAC frame to eavesdropping and replay attacks, hybrid encryption. The program at no extra cost on the basis of comprehensive protection of the safety of the EPON system data, but also to meet the needs of different users, the system has certain practical significance.%在分析了以太网无源光网络(EPON)网络中存在的安全隐患基础上,针对EPON网络中存在的安全问题,根据双向认证加密方案及技术路线,提出了一个抗MAC帧窃听和重放攻击的混合加密双向认证方案.该方案在不增加成本的基础上,全面地保障了EPON系统数据的安全,同时也满足了不同用户的需求,系统有一定的实用意义.
Low overhead two-way time synchronization algorithm%一种低开销的双向时间同步算法
汪付强; 曾鹏; 于海斌
2011-01-01
时间同步作为无线传感器网络的关键技术之一,得到越来越广泛的关注.提出了基于簇结构的主动和被动结合的双向同步算法,基于簇结构的双向同步方式解决了传统双向同步报文交互频繁的问题,通过最大似然估计校正节点间的相位偏差和频率偏差,使得同步算法获得较高的同步精度和相对较少的报文开销.最后通过仿真和物理实验验证了算法的有效性.%As one of the key technologies in wireless sensor networks, time synchronization has been widely concerned. A combined active and inactive two-way synchronization algorithm based on clustering architecture is proposed in this paper. The clustering architecture pattern solves the frequent packet interaction in traditional two way methods. The phase offset and frequency offset among nodes are corrected with maximum likelihood estimation. Based on these considerations,the proposed synchronization algorithm achieves high synchronization accuracy and relatively less packet cost. Finally , the efficacy of our algorithm is proved through simulation and physical experiments.
Two-way Comparative Pattern Matching Algorithm Suitable for Chinese%适合中文的双向比较模式匹配算法
叶煜
2011-01-01
Some pattern matching algorithms were analyzed and,an algorithm,suitable for Chinese,based on KMP was proposed,that is two-way pattern matching algorithm.Based on KMP,characteristic-array was introduced into to record the positional information of end character which appears in the pattern string and further to get the maximum moving distance of the pattern and the least times of comparing during the process of pattern string＇s matching.Experimental results show that two-way pattern matching algorithm can effectively reduce the times of matching.%分析了几种常用的模式匹配算法,提出一种适合于中文的基于KMP的改进算法,即双向比较模式匹配算法.该算法以KMP算法为基础,引入特征数组以记录模式串尾字符在模式串中出现的位置信息,从而获得模式串在匹配过程中的最大移动距离和最少比较次数.实验结果表明,双向比较模式匹配算法可有效降低匹配次数.
Lu, Lu; Li, Guoqiang
2016-06-15
Reversible elongation by cooling and contraction by heating, without the need for repeated programming, is well-known as the two-way shape-memory effect (2W-SME). This behavior is contrary to the common physics-contraction when cooling and expansion when heating. Materials with such behavior may find many applications in real life, such as self-sufficient grippers, fastening devices, optical gratings, soft actuators, and sealant. Here, it is shown that ionomer Surlyn 8940, a 50-year old polymer, exhibits both one-way multishape-memory effects and tunable two-way reversible actuation. The required external tensile stress to trigger the tunable 2W-SME is very low when randomly jumping the temperatures within the melting transition window. With a proper one-time programming, "true" 2W-SME (i.e., 2W-SME without the need for an external tensile load) is also achieved. A long training process is not needed to trigger the tunable 2W-SME. Instead, a proper one-time tensile programming is sufficient to trigger repeated and tunable 2W-SME. Because the 2W-SME of the ionomer Surlyn is driven by the thermally reversible network, here crystallization and melting transitions of the semicrystalline poly(ethylene-co-methacrylic acid), it is believed that a class of thermally reversible polymers should also exhibit tunable 2W-SMEs.
Understanding maximal repetitions in strings
Crochemore, Maxime
2008-01-01
The cornerstone of any algorithm computing all repetitions in a string of length n in O(n) time is the fact that the number of runs (or maximal repetitions) is O(n). We give a simple proof of this result. As a consequence of our approach, the stronger result concerning the linearity of the sum of exponents of all runs follows easily.
Herrera, Francisco Javier, Jr.
This study set out to examine how a web-based tool embedded with vocabulary strategies, as part of the science curriculum in a third grade two-way immersion classroom, would aid students' academic vocabulary development. Fourteen students (seven boys, seven girls; ten of which were English learners) participated in this study. Students utilized web pages as part of their science curriculum on the topic of ecology. The study documented students' use of the web pages as a data-gathering tool on the topic of ecology during science instruction. Students were video and audio taped as they explored the web pages. Results indicated that through the use of the intervention web pages students significantly improved their knowledge of academic English target words.
Picornell, C.; Cesari, E.; Sade, M.
1994-04-01
Training effects on the characteristics of the transformation when using pseudoelastic compressive cycling are studied from σ-ɛ curves and calorimetric measurements. Several characteristics produced by tensile cycling and observed in thermally induced martensitic transformations also appear in this case. For a fixed number of training cycles, the efficiency of the two-way shape memory effect (TWSME) obtained after compressive tests is higher than that measured when tensile experiments are done. In a certain range, the efficiency of the resulting TWSME after compressive training increases with the magnitude of the applied stress. Values of the stress (threshold stress) which trained samples with an induced TWSME are able to overcome when going to martensite are presented for two sets of samples. These opposing stresses are related to different degrees of the TWSME inhibition. These values increase with the number of compressive cycles and show a saturation behavior.
Picornell, C.; Cesari, E. (Univ. of the Balearic Islands, Palma de Mallorca (Spain). Physics Dept.); Sade, M. (Balseiro Inst., Bariloche (Argentina). National Commission of Atomic Energy National Univ. of Cuyo (Argentina). National Commission of Atomic Energy)
1994-04-01
Training effects on the characteristics of the transformation when using pseudoelastic compressive cycling are studied from [sigma]-[var epsilon] curves and calorimetric measurements. Several characteristics produced by tensile cycling and observed in thermally induced martensitic transformations also appear in this case. For a fixed number of training cycles, the efficiency of the two-way shape memory effect (TWSME) obtained after compressive tests is higher than that measured when tensile experiments are done. In a certain range, the efficiency of the resulting TWSME after compressive training increases with the magnitude of the applied stress. Values of the stress (threshold stress) which trained samples with an induced TWSME are able to overcome when going to martensite are presented for two sets of samples. These opposing stresses are related to different degrees of the TWSME inhibition. These values increase with the number of compressive cycles and show a saturation behavior.
文学与人类学的双向视野和认同%The Two-way Vision and Identity of Literature and Anthropology
彭子艺
2011-01-01
从文学和人类学各自的特点及二者的区别入手，观桑文学对人类学的影响和人类学对文学的渗透即二者的双向的视野和认同，促进我们对文学人类学进一步地认识和了解。%Through the characters and difference of literature and anthropology, this article makes researches on the influence of literature to anthropology and the percolation of anthropology to literature, which is the two-way vision and identity of literature and anthropology. Through the research, it can promote the understanding of literary anthropology.
Construction and Application of Two - Way Video Telemedicine System%双向视频远程医疗服务系统构建与应用
王倩云; 张红宾; 郭宏林; 朱刘松; 王茜
2011-01-01
The article discussed an new integration health care service mode. The service mode provided better medical care for retired cadres, which sharing medical resources between hospitals and sanatoria for retired cadres. The author also introduced the establishment and implement of Two - Way Video Telemedicine system in a military hospital.%医院与干休所互联互通互操作、医疗资源共享有的一体化医疗保健服务模式,为提升离退休干部医疗保健水平提供了先进手段和技术保证.本文探讨双向视频远程医疗服务系统的构建动因,阐述具体做法和取得的效果.
Tulgan, Henry
2014-01-01
Despite early widespread recognition of the necessity of continuing medical education (CME) for practicing physicians and surgeons, medical schools and national medical organizations were slow to mobilize to address the need. One pioneering program, developed by the Albany Medical College in New York, not only provided CME, but did so in a live distance education format that allowed for interaction between the participants and the faculty presenters. The Albany Program commenced in 1955 using what was then state-of-the-art technology; it exemplified principles and practices that can be seen as the precursors for the distance education approaches used to reach physicians today. This short article describes the contributions of the Albany Two-Way Radio Conferences and places them in the context of developments in national organizations and policies in the 20th century.
Forist, B. E.; Knapp, D.
2014-12-01
Much interpretation in units of the National Park System, conducted by National Park Service (NPS) rangers and partners today is done in a didactic, lecture style. This "one-way" communication runs counter to research suggesting that long-term impacts of park interpretive experiences must be established through direct connections with the visitor. Previous research in interpretation has suggested that interpretive experiences utilizing a "two-way" dialogue approach are more successful at facilitating long-term memories than "one-way" approaches where visitors have few, if any, opportunities to ask questions, offer opinions, or share interests and experiences. Long-term memories are indicators of connections to places and resources. Global anthropogenic change poses critical threats to NPS sites, resources, and visitor experiences. As climate change plays an ever-expanding role in public, political, social, economic, and environmental discourse it stands to reason that park visitors may also be interested in engaging in this discourse. Indeed, NPS Director Jonathan Jarvis stated in the agency's Climate Change Action Plan 2012 - 2014 that, "We now know through social science conducted in parks that our visitors are looking to NPS staff for honest dialogue about this critical issue." Researchers from Indiana University will present preliminary findings from a multiple park study that assessed basic visitor knowledge and the impact of two-way interpretation related to climate change. Observations from park interpretive program addressing climate change will be presented. Basic visitor knowledge of climate change impacts in the select parks as well as immediate and long-term visitor recollections will be presented. Select units of the National Park System in this research included Cape Cod National Seashore, Cape Hatteras National Seashore, North Cascades National Park, Shenandoah National Park, and Zion National Park.
Hwang, Eunju; Kim, Kyung Jae; Choi, Bong Dae
In IEEE 802.16e, power saving is one of the important issues for battery-powered mobile stations (MSs). We present a performance analysis of power saving class (PSC) of type I in IEEE 802.16e standard for voice over Internet protocol (VoIP) service with silence suppression in two-way communication. On-off pattern of a voice user in two-way communication is characterized by the modified Brady model, which includes short silence gaps less than 200ms and talkspurt periods shorter than 15ms, and so differs from the Brady model. Our analysis of PSC I follows the standard-based procedure for the deactivation of the sleep mode, where a uplink packet arrival during a mutual silence period wakes up the MS immediately while a downlink packet arrival waits to be served until the next listening window. We derive the delay distribution of the first downlink packet arriving during a mutual silence period, and find the dropping probability of downlink packets since a voice packet drops if it is not transmitted within maximum delay constraint. In addition, we calculate the average power consumption under the modified Brady model. Analysis and simulation results show that the sleep mode operation for the MS with VoIP service yields 32 ∼ 39% reduction in the power consumption of the MS. Finally we obtain the optimal initial/final-sleep windows that yield the minimum average power consumption while satisfying QoS constraints on the packet dropping probability and the maximum delay.
Pandini, Stefano; Riccò, Theonis; Borboni, Alberto; Bodini, Ileana; Vetturi, David; Cambiaghi, Danilo; Toselli, Maurizio; Paderni, Katia; Messori, Massimo; Pilati, Francesco; Chiellini, Federica; Bartoli, Cristina
2014-07-01
This paper investigates the shape memory capabilities of semicrystalline networks, focusing the attention on poly(ɛ-caprolactone) (PCL) systems, a class of materials that allows to satisfy important requirements for their applications as biomedical devices, such as the good biocompatibility, the fast recovery of large "temporary" shape configurations, and the easy tailoring of the transformation temperatures. The materials were prepared with various crosslink densities and crosslinking methodologies; in particular, beside a thermal crosslinking based on reactive methacrylic end groups, a novel type of covalently crosslinked semicrystalline systems was prepared by a sol-gel approach from alkoxysilane-terminated PCL precursors, so as to avoid potentially toxic additives typically used for free-radical thermal curing. The materials were subjected to biological tests, to study their ability in sustaining cell adhesion and proliferation, and to thermal characterizations, to evaluate the possibility to tailor their melting and crystallization temperatures. The one-way shape memory (i.e., the possibility to set the material in a given configuration and to recover its pristine shape) and the two-way shape memory response (i.e., the triggered change between two distinguished shapes on the application of an on-off stimulus) were studied by applying optimized thermo-mechanical cyclic histories. The ability to fix the applied shape and to recover the original one on the application of heating (i.e., the one-way effect) was evaluated on tensile bars; further, to investigate a potential application as self-expandable stents, isothermal shape memory experiments were carried out also on tubular specimens, previously folded in a temporary compact configuration. The two-way response was studied through the application of a constant load and of a heating/cooling cycle from above melting to below the crystallization temperature, leading to a reversible elongation/contraction effect
Sánchez-González, Ana; Esnal, Aitor; Río-Álamos, Cristóbal; Oliveras, Ignasi; Cañete, Toni; Blázquez, Gloria; Tobeña, Adolf; Fernández-Teruel, Alberto
2016-03-01
This study presents the first evaluation of the associations between responses in two paradigms related to schizophrenia in the genetically heterogeneous NIH-HS rat stock. NIH-HS rats are a stock of genetically heterogeneous animals that have been derived from eight different inbred strains. A rotational breeding schedule has been followed for more than eighty generations, leading to a high level of genetic recombination that makes the NIH-HS rats a unique tool for studying the genetic basis of (biological, behavioral, disease-related) complex traits. Previous work has dealt with the characterization of coping styles, cognitive and anxiety/fear-related profiles of NIH-HS rats. In the present study we have completed their characterization in two behavioral models, prepulse inhibition (PPI) and latent inhibition (LI) of the two-way active avoidance response, that appear to be related to schizophrenia or to schizophrenia-relevant symptoms. We have found that these rats display PPI for each of the four prepulse intensities tested, allowing their stratification in high, medium and low PPI subgroups. When testing these three subgroups for LI of two-way active avoidance acquisition it has been observed that the LowPPI and MediumPPI subgroups present impaired LI, which, along with the fact that the HighPPI group presents significant LI, allows us to hypothesize that responses in these two paradigms are somehow related and that selection of NIH-HS rats for Low vs HighPPI could make a promising animal model for the study of clusters of schizophrenia-relevant symptoms and their underlying neurobiological mechanisms.
Note on maximal distance separable codes
YANG Jian-sheng; WANG De-xiu; JIN Qing-fang
2009-01-01
In this paper, the maximal length of maximal distance separable(MDS)codes is studied, and a new upper bound formula of the maximal length of MDS codes is obtained. Especially, the exact values of the maximal length of MDS codes in some parameters are given.
Maximization, learning, and economic behavior.
Erev, Ido; Roth, Alvin E
2014-07-22
The rationality assumption that underlies mainstream economic theory has proved to be a useful approximation, despite the fact that systematic violations to its predictions can be found. That is, the assumption of rational behavior is useful in understanding the ways in which many successful economic institutions function, although it is also true that actual human behavior falls systematically short of perfect rationality. We consider a possible explanation of this apparent inconsistency, suggesting that mechanisms that rest on the rationality assumption are likely to be successful when they create an environment in which the behavior they try to facilitate leads to the best payoff for all agents on average, and most of the time. Review of basic learning research suggests that, under these conditions, people quickly learn to maximize expected return. This review also shows that there are many situations in which experience does not increase maximization. In many cases, experience leads people to underweight rare events. In addition, the current paper suggests that it is convenient to distinguish between two behavioral approaches to improve economic analyses. The first, and more conventional approach among behavioral economists and psychologists interested in judgment and decision making, highlights violations of the rational model and proposes descriptive models that capture these violations. The second approach studies human learning to clarify the conditions under which people quickly learn to maximize expected return. The current review highlights one set of conditions of this type and shows how the understanding of these conditions can facilitate market design.
双向纤维腹板增强夹层结构的弯曲性能%Flexural Behavior of Two-way Fiber Reinforced Sandwich Structure
刘子建; 刘伟庆; 万里; 方海; 陆伟东
2012-01-01
设计并制备了双向纤维腹板增强复合材料夹层梁,对其受弯性能进行了四点弯曲试验研究,开展单、双向格构夹层梁性能对比分析,研究不同腹板高度、厚度对夹层梁受弯性能的影响,基于经典夹层梁理论及简支梁受弯基本理论,研究夹层梁破坏模式和机理。试验结果表明：双向格构腹板增强形式能有效提高该夹层结构的极限变形能力与受弯极限承载力,且随着试件厚度加大提高作用更明显;保持夹层梁基本参数不变,增加试件高度有利于提高刚度,增强夹层梁极限承载力;单一增加腹板厚度有益于提高该夹层梁的极限变形能力,但不能明显提高其极限承载力。理论分析表明：采用铁木辛柯梁理论求得的挠度理论值与实验值吻合较好。%Two-way fiber reinforced sandwich beam was designed and fabricated by vacuum infusion molding process(VIMP).Flexural behavior of the beam was experimentally analyzed by the four-point bending test.Comparative analysis was made between the one-and two-way sandwich beams,and then the failure mode were observed from the test species with different webs height and web thickness.Based on the classic sandwich beam theory and the bending theory of simply supported beam,the ultimate bearing capacity and the failure mode of the sandwich composites beam were studied.It is concluded that the extreme deformation ability and the ultimate bearing capacity could be improved by the two-way lattice webs,while the improvement would become obvious with increasing sample thickness.Besides,both the stiffness and ultimate bearing capacity could also be effectively enhanced by increasing web height.Moreover,the extreme deformation could be improved by increasing web thickness,while the improvement of ultimate bearing capacity could hardly be observed.In addition,theoretical analysis indicates that deflection calculated by Timoshenko Beam Theory is in good accordance with the
Maximizing production rates of the Linde Hampson machine
Maytal, B.-Z.
2006-01-01
In contrast to the ideal case of unlimited size recuperator, any real Linde-Hampson machine of finite size recuperator can be optimized to reach the extreme rates of performance. The group of cryocoolers sharing the same size recuperator is optimized in a closed form by determining the corresponding flow rate which maximizes its rate of cold production. For a similar group of liquefiers an optimal flow rate is derived to maximize the rate of production of liquid cryogen. The group of cryocoolers sharing a constant and given flow rate is optimized by shortening the recuperator for reaching a maximum compactness measured by the cooling power per unit size of the recuperator. The optimum conditions are developed for nitrogen and argon. The relevance of this analysis is discussed in the context of practice of fast cooldown Joule-Thomson cryocooling.
基于ARM处理器的两路超声波测距仪设计%Two-way Ultrasonic Range Finder Design Based on ARM Embeded Processor
徐军; 孙振伟; 王华东
2012-01-01
结合嵌入式处理器LM3S1607与超声波传感器设计一种智能超声波测距装置,采用ARM内核芯片LM3S1607的32位嵌入式微处理器与两片P89LPC938单片机和超声波传感器发送与接收模块,通过I2C串行总线上下位机的通信架构,实现两路超声波测距.通过高精度温度传感器LM75A实现了对超声波测距系统的温度测量,对超声波的声速进行了补偿,提高了测量精度,同时具有LCD液晶显示测试距离,语音播放距离功能.设计和开发了相应的接口电路及应用程序,介绍了两路超声波测距仪的设计方法.%Combined with the embedded processor LM3S1607 with ultrasonic sensor, an intelligent ultrasonic distance measuring device is designed in this article. The 32-bit embedded microprocessor of the ARM core chip LM3S1607 is used. Sending and receiving modules are made up of two pieces of P89LPC938 microcontroller and ultrasonic sensors. Communication architecture of upper and lower computer is formed via the I2C serial bus to achieve two-way ultrasonic distance measuring. Temperature measurement of ultrasonic ranging system is realized through the high-precision temperature sensor LM75A. Ultrasonic sound velocity is compensated to improve the measurement accuracy. Meanwhile the distance measuring device has the function of LCD displaying and voice broadcast test distance. Interface circuit and application program are designed and developed. The design method of two-way ultrasonic range finder is also introduced.
Asymptotics of robust utility maximization
Knispel, Thomas
2012-01-01
For a stochastic factor model we maximize the long-term growth rate of robust expected power utility with parameter $\\lambda\\in(0,1)$. Using duality methods the problem is reformulated as an infinite time horizon, risk-sensitive control problem. Our results characterize the optimal growth rate, an optimal long-term trading strategy and an asymptotic worst-case model in terms of an ergodic Bellman equation. With these results we propose a duality approach to a "robust large deviations" criterion for optimal long-term investment.
Multivariate residues and maximal unitarity
Søgaard, Mads; Zhang, Yang
2013-12-01
We extend the maximal unitarity method to amplitude contributions whose cuts define multidimensional algebraic varieties. The technique is valid to all orders and is explicitly demonstrated at three loops in gauge theories with any number of fermions and scalars in the adjoint representation. Deca-cuts realized by replacement of real slice integration contours by higher-dimensional tori encircling the global poles are used to factorize the planar triple box onto a product of trees. We apply computational algebraic geometry and multivariate complex analysis to derive unique projectors for all master integral coefficients and obtain compact analytic formulae in terms of tree-level data.
Beeping a Maximal Independent Set
Afek, Yehuda; Alon, Noga; Bar-Joseph, Ziv; Cornejo, Alejandro; Haeupler, Bernhard; Kuhn, Fabian
2012-01-01
We consider the problem of computing a maximal independent set (MIS) in an extremely harsh broadcast model that relies only on carrier sensing. The model consists of an anonymous broadcast network in which nodes have no knowledge about the topology of the network or even an upper bound on its size. Furthermore, it is assumed that an adversary chooses at which time slot each node wakes up. At each time slot a node can either beep, that is, emit a signal, or be silent. At a particular time slot...
Maximal Congruences on Some Semigroups
Jintana Sanwong; R.P. Sullivan
2007-01-01
In 1976 Howie proved that a finite congruence-free semigroup is a simple group if it has at least three elements but no zero elementInfinite congruence-free semigroups are far more complicated to describe, but some have been constructed using semigroups of transformations (for example, by Howie in 1981 and by Marques in 1983)Here, forcertain semigroups S of numbers and of transformations, we determine all congruences p on S such that S/p is congruence-free, that is, we describe all maximal congruences on such semigroups S.
Research on Electronic Job Service Model Based on Two-way Demand%基于双向需求的电子就业服务模型研究
唐新亭
2011-01-01
In order to deal with the rubbish information inundation of electronic job market, a service model is proposed with two-way demand. According to the actual demands of recruiters and applicants, the system structure, the data structure and the working flow are given. This paper discusses the demand matching between recruiters and applicants, and mass candidates filtering and the communicating realization issue between agencies. Experimental results show that the model can match and manage both sides information effectively, fasten filtering rate of the resumes.%针对电子就业市场垃圾信息泛滥的现状,提出基于双向需求的服务模型.根据招聘者和应聘者的实际需求,给出该模型的体系结构、数据结构与运行流程,研究招聘双方需求匹配、海量候选者筛选的方法以及代理间通信的实现间题.实验结果表明,该模型能实现高效的双方信息匹配与管理,提高简历筛选速度.
Maximizing residual capacity in connection-oriented networks
Krzysztof Walkowiak
2006-07-01
Full Text Available The following problem arises in the study of survivable connection-oriented networks. Given a demand matrix to be routed between nodes, we want to route all demands, so that the residual capacity given by the difference between link capacity and link flow is maximized. Each demand can use only one path. Therefore, the flow is modeled as nonbifurcated multicommodity flow. We call the considered problem nonbifurcated congestion (NBC problem. Solving NBC problem enables robust restoration of failed connections in a case of network failure. We propose a new heuristic algorithm for NBC problem and compare its performance with existing algorithms.
Knowledge discovery by accuracy maximization.
Cacciatore, Stefano; Luchinat, Claudio; Tenori, Leonardo
2014-04-01
Here we describe KODAMA (knowledge discovery by accuracy maximization), an unsupervised and semisupervised learning algorithm that performs feature extraction from noisy and high-dimensional data. Unlike other data mining methods, the peculiarity of KODAMA is that it is driven by an integrated procedure of cross-validation of the results. The discovery of a local manifold's topology is led by a classifier through a Monte Carlo procedure of maximization of cross-validated predictive accuracy. Briefly, our approach differs from previous methods in that it has an integrated procedure of validation of the results. In this way, the method ensures the highest robustness of the obtained solution. This robustness is demonstrated on experimental datasets of gene expression and metabolomics, where KODAMA compares favorably with other existing feature extraction methods. KODAMA is then applied to an astronomical dataset, revealing unexpected features. Interesting and not easily predictable features are also found in the analysis of the State of the Union speeches by American presidents: KODAMA reveals an abrupt linguistic transition sharply separating all post-Reagan from all pre-Reagan speeches. The transition occurs during Reagan's presidency and not from its beginning.
Inapproximability of maximal strip recovery
Jiang, Minghui
2009-01-01
In comparative genomic, the first step of sequence analysis is usually to decompose two or more genomes into syntenic blocks that are segments of homologous chromosomes. For the reliable recovery of syntenic blocks, noise and ambiguities in the genomic maps need to be removed first. Maximal Strip Recovery (MSR) is an optimization problem proposed by Zheng, Zhu, and Sankoff for reliably recovering syntenic blocks from genomic maps in the midst of noise and ambiguities. Given $d$ genomic maps as sequences of gene markers, the objective of \\msr{d} is to find $d$ subsequences, one subsequence of each genomic map, such that the total length of syntenic blocks in these subsequences is maximized. For any constant $d \\ge 2$, a polynomial-time 2d-approximation for \\msr{d} was previously known. In this paper, we show that for any $d \\ge 2$, \\msr{d} is APX-hard, even for the most basic version of the problem in which all gene markers are distinct and appear in positive orientation in each genomic map. Moreover, we provi...
Maximal right smooth extension chains
Huang, Yun Bao
2010-01-01
If $w=u\\alpha$ for $\\alpha\\in \\Sigma=\\{1,2\\}$ and $u\\in \\Sigma^*$, then $w$ is said to be a \\textit{simple right extension}of $u$ and denoted by $u\\prec w$. Let $k$ be a positive integer and $P^k(\\epsilon)$ denote the set of all $C^\\infty$-words of height $k$. Set $u_{1},\\,u_{2},..., u_{m}\\in P^{k}(\\epsilon)$, if $u_{1}\\prec u_{2}\\prec ...\\prec u_{m}$ and there is no element $v$ of $P^{k}(\\epsilon)$ such that $v\\prec u_{1}\\text{or} u_{m}\\prec v$, then $u_{1}\\prec u_{2}\\prec...\\prec u_{m}$ is said to be a \\textit{maximal right smooth extension (MRSE) chains}of height $k$. In this paper, we show that \\textit{MRSE} chains of height $k$ constitutes a partition of smooth words of height $k$ and give the formula of the number of \\textit{MRSE} chains of height $k$ for each positive integer $k$. Moreover, since there exist the minimal height $h_1$ and maximal height $h_2$ of smooth words of length $n$ for each positive integer $n$, we find that \\textit{MRSE} chains of heights $h_1-1$ and $h_2+1$ are good candidates t...
Mining Maximal Frequent Patterns in a Unidirectional FP-tree
SONG Jing-jing; LIU Rui-xin; WANG Yan; JIANG Bao-qing
2006-01-01
Becausemining complete set of frequent patterns from dense database could be impractical, an interesting alternative has been proposed recently. Instead of mining the complete set of frequent patterns, the new model only finds out the maximal frequent patterns, which can generate all frequent patterns. FP-growth algorithm is one of the most efficient frequent-pattern mining methods published so far. However,because FP-tree and conditional FP-trees must be two-way traversable, a great deal memory is needed in process of mining. This paper proposes an efficient algorithm Unid_FP-Max for mining maximal frequent patterns based on unidirectional FP-tree. Because of generation method of unidirectional FP-tree and conditional unidirectional FP-trees, the algorithm reduces the space consumption to the fullest extent. With the development of two techniques:single path pruning and header table pruning which can cut down many conditional unidirectional FP-trees generated recursively in mining process, Unid_ FP-Max further lowers the expense of time and space.
The Comparison of Two Ways for Digital Channelization%两种数字信道化实现方法比较
左佑; 高希光
2016-01-01
Digital channelized receiver plays an important role in modern ESM system. Two ways for digital channelization are proposed:poly-phase filter banks and STFT. Their differences of implement principle and performance are analyzed and verified by simulations. The results will give some references for future ESM receiver designs.%现代电子侦察系统中，数字信道化接收机扮演着十分重要的角色。研究了工程上常用的两种数字信道化实现方法：多相滤波器组法和短时傅里叶变换STFT法，对他们的实现原理和性能进行了分析比较，并通过仿真进一步验证了两者的性能差异，为侦察接收机设计提供一定参考。
Carvalho, Juliana Dias Melo; de Oliveira, Amanda R; da Silva, Regina Claudia Barbosa; Brandão, Marcus L
2009-04-01
In recent years, studies in behavioral pharmacology have shown the involvement of dopaminergic mechanisms in avoidance behavior as assessed by the two-way active avoidance test (CAR). Changes in dopaminergic transmission also occur in response to particularly threatening challenges. However, studies on the effects of benzodiazepine (BZD) drugs in this test are still unclear. Given the interplay of dopamine and other neurotransmitters in the neurobiology of anxiety and schizophrenia the aim of this work was to evaluate the effects of systemic administration of midazolam, the dopaminergic agonist apomorphine, and the D2 receptor antagonist sulpiride using the CAR, a test that shows good sensitivity to typical neuroleptic drugs. Whereas midazolam did not alter the avoidance response, apomorphine increased and sulpiride reduced them in this test. Escape was not affected by any drug treatments. Heightened avoidance was not associated with the increased motor activity caused by apomorphine. In contrast with the benzodiazepine midazolam, activation of post-synaptic D2 receptors with apomorphine facilitates, whereas the D2 receptor antagonism with sulpiride inhibited the acquisition of the avoidance behavior. Together, these results bring additional evidence for a role of D2 mechanisms in the acquisition of the active avoidance.
Ozaki, Koken; Toyoda, Hideki
2005-06-01
The purpose of this research is to provide a two-way analysis of variance (ANOVA) model for a latent factor. Typical psychological studies measure mental states with questionnaires and analyze the variance of the measures into the portions attributable to various sources. This type of research, when conducted under regular ANOVA designs, uses total score as the dependent measures. However, this method is based on the unrealistic presumption that every item on the questionnaire has the same factor loading on the attribute being measured. In this research, we incorporated factor analysis model, and used a latent factor instead of total score as the dependent measure, thereby applying ANOVA under a more realistic assumption. Structural Equation Modeling (SEM) was used to express statistical models. This paper also examined a relation between music and mood, which is a quite popular area of research in psychology of music. To study the possible effects of tonality and key-signature on mood, music was chosen to represent tonality and key-signature conditions.
Mehrabi, K.; Bruncko, M.; Kneissl, A. C.
2013-05-01
This paper discusses the application of rapid solidification by the melt-spinning method for the preparation of thin NiTi-based ribbons. Generally, the application of rapid solidification via melt-spinning can change the microstructure, improving the ductility and shape memory characteristics and lead to small-dimensioned samples. Several thousand thermal cycles were performed on the trained ribbons using bending deformation procedure, continuously observing the changes in the shape memory and transformation behaviors. These changes are due to the appearance of an intermediate phase which was stabilized probably by the accumulation of defects introduced by thermomechanical training. The influence of training and thermal cycling on characteristics of ribbons was studied by x-ray diffraction and transmission electron microscopy and differential scanning calorimetry. The results displayed that bending training methods were useful in developing a two-way shape memory effect (TWSME). All samples show a shape memory effect immediately after processing without further heat treatment. The addition of copper in NiTi alloys was effective to narrow the transformation hysteresis. The W addition has improved the stability of the TWSME and mechanical properties. The TWSME of ribbons and its stability are well suited for important applications such as microsensors and microactuators.
Yuhui Li; Yingxia Yang; Jidong Liu; Xiuliang Wang; Tianxiang Gao; Delin Duan
2007-01-01
With a "two-way pseudo-testcross" mapping strategy, we applied the amplified fragment length polymorphism (AFLP) markers to construct two moderate density genetic linkage maps for Laminaria. The linkage maps were generated from the 60 progenies of the F1 cross family (Laminaria longissima Aresch. x L. japonica Miyabe) with twenty pairs of primer combinations. Of the 333 polymorphic loci scored in 60 progenies, 173 segregated in a 1:1ratio, corresponding to DNA polymorphisms heterozygous in a single parent, and the other 58 loci existing in both parents followed a 3:1 Mendelian segregation ratio. Among the loci with 1:1 segregating ratios, 79 loci were ordered in 14 linkage groups (648.6 cM) of the paternal map, and 72 loci were ordered in 14 linkage groups (601.9 cM) of the maternal map. The average density of loci was approximately 1 per 8 cM. To investigate the homologies between two parental maps, we used 58 loci segregated 3:1 for further analysis, and deduced one homologous linkage group. The linkage data developed in these maps will be useful for detecting loci-controlling commercially important traits for Laminaria.
Ruili Huo
2015-01-01
Full Text Available In recent years, the sandwich bridge decks with GFRP face sheets and light weight material core have been widely used in the world due to their advantages of low cost, high strength to weight ratios, and corrosion resisting. However, as the bridge decks, most of them are used in foot bridges rather than highway bridges because the ultimate bending strength and initial bending stiffness are relatively low. To address this issue and expand the scope of use, a simple and innovative sandwich bridge deck with GFRP face sheets and a foam-web core, manufactured by vacuum assisted resin infusion process, is developed. An experimental study was carried out to validate the effectiveness of this panel for increasing the ultimate bending strength and initial bending stiffness under two-way bending. The effects of face sheet thickness, foam density, web thickness, and web spacing on displacement ductility and energy dissipation were also investigated. Test results showed that, compared to the normal foam-core sandwich decks, an average approximately 657.1% increase in the ultimate bending strength can be achieved. Furthermore, the bending stiffness, displacement ductility, and energy dissipation can be enhanced by increasing web thickness, web height, and face sheet thickness or decreasing web spacing.
Carlos José de Araújo
2001-07-01
Full Text Available In this work, several tests of thermal cycling under constant load are carried out on Ti-45.0Ni-5.0Cu (at% shape memory wires. The properties related to the Stress Assisted Two Way Memory Effect (SATWME of the material are investigated as a function of the mechanical loading history for the same temperature range during cooling and heating. For this reason, two thermomechanical tests have been employed: tests I, where one sample is used for just one constant stress level test and tests II, where only one sample is employed for several constant stress level tests in sequence. The results obtained show that for loads applied below 150 MPa, the transformation temperatures and the thermal hysteresis associated with the transformation of the material are the same during the two tests. However, above 150 MPa in tests II transformation temperatures and thermal hysteresis are respectively higher and smaller than the ones obtained in tests I. On the other hand, transformation temperatures obtained from both tests are in good agreement with the ones measured by DSC and electrical resistance measurements. It is also observed that the SATWME obtained by tests II is smaller than the one measured during tests I. It is shown that these different behaviors are induced by accumulation of plastic strain in the sample during tests II.
Datta, Subimal; Siwek, Donald F; Huang, Max P
2009-07-01
Previous studies have shown that two-way active avoidance (TWAA) memory processing involves a functional interaction between the pontine wave (P wave) generator and the CA3 region of the dorsal hippocampus (DH-CA3). The present experiments examined whether the interaction between P wave generator activity and the DH-CA3 involves the intracellular protein kinase A (PKA) signaling system. In the first series of experiments, rats were subjected to a session of TWAA training followed immediately by bilateral microinjection of either the PKA activation inhibitor (KT-5720) or vehicle control into the DH-CA3 and tested for TWAA memory 24 h later. The results indicated that immediate KT-5720 infusion impaired improvement of TWAA performance. Additional experiments showed that KT-5720 infusion also blocked TWAA training-induced BDNF expression in the DH-CA3. Together, these findings suggest that the PKA activation and BDNF expression in the DH-CA3 is essential for the improvement of TWAA memory.
The maximal D = 4 supergravities
Wit, Bernard de [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, Postbus 80.195, NL-3508 TD Utrecht (Netherlands); Samtleben, Henning [Laboratoire de Physique, ENS Lyon, 46 allee d' Italie, F-69364 Lyon CEDEX 07 (France); Trigiante, Mario [Dept. of Physics, Politecnico di Torino, Corso Duca degli Abruzzi 24, I-10129 Turin (Italy)
2007-06-15
All maximal supergravities in four space-time dimensions are presented. The ungauged Lagrangians can be encoded in an E{sub 7(7)}-Sp(56; R)/GL(28) matrix associated with the freedom of performing electric/magnetic duality transformations. The gauging is defined in terms of an embedding tensor {theta} which encodes the subgroup of E{sub 7(7)} that is realized as a local invariance. This embedding tensor may imply the presence of magnetic charges which require corresponding dual gauge fields. The latter can be incorporated by using a recently proposed formulation that involves tensor gauge fields in the adjoint representation of E{sub 7(7)}. In this formulation the results take a universal form irrespective of the electric/magnetic duality basis. We present the general class of supersymmetric and gauge invariant Lagrangians and discuss a number of applications.
Maximizing profit using recommender systems
Das, Aparna; Ricketts, Daniel
2009-01-01
Traditional recommendation systems make recommendations based solely on the customer's past purchases, product ratings and demographic data without considering the profitability the items being recommended. In this work we study the question of how a vendor can directly incorporate the profitability of items into its recommender so as to maximize its expected profit while still providing accurate recommendations. Our approach uses the output of any traditional recommender system and adjust them according to item profitabilities. Our approach is parameterized so the vendor can control how much the recommendation incorporating profits can deviate from the traditional recommendation. We study our approach under two settings and show that it achieves approximately 22% more profit than traditional recommendations.
The maximal D=5 supergravities
de Wit, Bernard; Trigiante, M; Wit, Bernard de; Samtleben, Henning; Trigiante, Mario
2007-01-01
The general Lagrangian for maximal supergravity in five spacetime dimensions is presented with vector potentials in the \\bar{27} and tensor fields in the 27 representation of E_6. This novel tensor-vector system is subject to an intricate set of gauge transformations, describing 3(27-t) massless helicity degrees of freedom for the vector fields and 3t massive spin degrees of freedom for the tensor fields, where the (even) value of t depends on the gauging. The kinetic term of the tensor fields is accompanied by a unique Chern-Simons coupling which involves both vector and tensor fields. The Lagrangians are completely encoded in terms of the embedding tensor which defines the E_6 subgroup that is gauged by the vectors. The embedding tensor is subject to two constraints which ensure the consistency of the combined vector-tensor gauge transformations and the supersymmetry of the full Lagrangian. This new formulation encompasses all possible gaugings.
Constraint Propagation as Information Maximization
Abdallah, A Nait
2012-01-01
Dana Scott used the partial order among partial functions for his mathematical model of recursively defined functions. He interpreted the partial order as one of information content. In this paper we elaborate on Scott's suggestion of regarding computation as a process of information maximization by applying it to the solution of constraint satisfaction problems. Here the method of constraint propagation can be interpreted as decreasing uncertainty about the solution -- that is, as gain in information about the solution. As illustrative example we choose numerical constraint satisfaction problems to be solved by interval constraints. To facilitate this approach to constraint solving we formulate constraint satisfaction problems as formulas in predicate logic. This necessitates extending the usual semantics for predicate logic so that meaning is assigned not only to sentences but also to formulas with free variables.
A.C. Troncoso
1998-03-01
Full Text Available The inferior colliculus is a primary relay for the processing of auditory information in the brainstem. The inferior colliculus is also part of the so-called brain aversion system as animals learn to switch off the electrical stimulation of this structure. The purpose of the present study was to determine whether associative learning occurs between aversion induced by electrical stimulation of the inferior colliculus and visual and auditory warning stimuli. Rats implanted with electrodes into the central nucleus of the inferior colliculus were placed inside an open-field and thresholds for the escape response to electrical stimulation of the inferior colliculus were determined. The rats were then placed inside a shuttle-box and submitted to a two-way avoidance paradigm. Electrical stimulation of the inferior colliculus at the escape threshold (98.12 ± 6.15 (A, peak-to-peak was used as negative reinforcement and light or tone as the warning stimulus. Each session consisted of 50 trials and was divided into two segments of 25 trials in order to determine the learning rate of the animals during the sessions. The rats learned to avoid the inferior colliculus stimulation when light was used as the warning stimulus (13.25 ± 0.60 s and 8.63 ± 0.93 s for latencies and 12.5 ± 2.04 and 19.62 ± 1.65 for frequencies in the first and second halves of the sessions, respectively, P0.05 in both cases. Taken together, the present results suggest that rats learn to avoid the inferior colliculus stimulation when light is used as the warning stimulus. However, this learning process does not occur when the neutral stimulus used is an acoustic one. Electrical stimulation of the inferior colliculus may disturb the signal transmission of the stimulus to be conditioned from the inferior colliculus to higher brain structures such as amygdala
Designing of the Two-way Suction Drainage Tube in Vacuum Sealing%封闭负压双向引流管的设计
雷林革; 闫宛春; 陈克明
2012-01-01
目的 探讨改良传统VSD的单向负压引流为双向引流,以适应临床治疗的需要,防止堵管.方法 将传统VSD内含的多侧孔引流单向盲管改为双向引流多侧孔管,聚乙烯酒精水化海藻盐泡沫,聚氨酯和丙烯半透性粘贴薄膜与传统VSD相同.结果 采用双向引流多侧孔管VSD可减少堵管几率,并可对复杂感染创面进行对流冲洗,创造生理湿性愈合环境,促进创面愈合.结论 利用改良VSD技术减少了VSD失效几率,提高治疗效果.%Objective To investigate the traditional VSD from one-way improvement to two-way suction drainage, meet the needs of clinical treatment, and prevent bung tube. Methods One-way multi-side hole drainage tube of the traditional VSD was modified for bi-directional mufti-side hole drainage, seaweed salt hydration alcohol polyethylene foam, Semipemneable membrane paste of Polyurethane and acrylic remains the same with that of the traditional VSD. Results The applications of bi-directional multi-side hole drainage pipe can reduce the rate of plugging, rinse the complex and infection wound, create a physiological moist healing environment, and promote wound healing. Conclusions The improved VSD can reduce the failure rate and increase the therapeutic effect.
DENG Zeng'an; XIE Li'an; HAN Guijun; ZHANG Xuefeng; WU Kejian
2012-01-01
We investigated the Stokes drift-driven ocean currents and Stokes drift-induced wind energy input into the upper ocean using a two-way coupled wave-current modeling system that consists of the Princeton Ocean Model generalized coordinate system (POMgcs),Simulating WAves Nearshore (SWAN) wave model,and the Model Coupling Toolkit (MCT).The Coriolis-Stokes forcing (CSF) computed using the wave parameters from SWAN was incorporated with the momentum equation of POMgcs as the core coupling process.Experimental results in an idealized setting show that under the steady state,the scale of the speed of CSF-driven current was 0.001 m/s and the maximum reached 0.02 rn/s.The Stokes drift-induced energy rate input into the model ocean was estimated to be 28.5 GW,taking 14％ of the direct wind energy rate input.Considering the Stokes drift effects,the total mechanical energy rate input was increased by approximately 14％,which highlights the importance of CSF in modulating the upper ocean circulation.The actual run conducted in Taiwan Adjacent Sea (TAS) shows that:1) CSF-based wave-current coupling has an impact on ocean surface currents,which is related to the activities of monsoon winds; 2) wave-current coupling plays a significant role in a place where strong eddies present and tends to intensify the eddy's vorticity; 3) wave-current coupling affects the volume transport of the Taiwan Strait (TS) throughflow in a nontrivial degree,3.75％ on average.
Sato, T; Deiwick, A; Raddatz, G; Koyama, K; Schlitt, H J
1999-01-01
With organ allografts considerable numbers of donor-type mononuclear cells are transferred to the recipient, leading to bilateral immunological interactions between donor and recipient lymphocytes. To study such bilateral immune reactions in detail, human two-way MLC were performed. In this model proliferation kinetics, patterns of activation, and survival of the two populations were analysed, and the relevance of initial cell subset composition, relative cell numbers, and the effect of immunosuppression on this co-culture were evaluated. It could be demonstrated that with an initial 50:50 ratio of two populations of allogeneic cells one population dominated after 21 days of co-culture in 78 out of 80 combinations (97%) tested; the other population decreased markedly after an initially stable phase of 6–7 days. With unequal starting conditions the larger population dominated when resting cells were used, but small populations of preactivated cells or separated CD8+ cells could also dominate. Depletion of CD16+ natural killer (NK) cells and of CD2− cells (B cell and monocytes) had no effect on domination. Addition of cyclosporin delayed or blocked the domination process while addition of IL-2 accelerated it. Disappearance of one population was associated with detection of apoptotic cells. The findings indicate that co-cultures of allogeneic mononuclear cells are generally not stable for more than 1 week, but lead to active elimination of one population. CD8+ cells and particularly preactivated cells seem to play the most important role in that process, while NK cells are of less importance. Cyclosporin can prolong survival of allogeneic cells in co-culture. These observations suggest that under the conditions of clinical organ transplantation even small amounts of immunocompetent donor cells transferred by the graft may persist for some time and may, thereby, have the chance to exert immunomodulatory functions. PMID:9933457
Shahriari M
2015-05-01
Full Text Available Background and Objective: Proper nutritional support is one of the important caring aspects in patients who were hospitalized in Intensive Care Unit. Although the several studies have been done concerning the selection of proper nutrition method for patients, but there is no agreement on this issue. The aim of current study was the compare the effect of two ways of tube feeding including bolus and continuous infusion on gastric residual volume and diarrhea in patients hospitalized in Intensive Care Unit. Materials and Method: The current clinical trial was conducted on patients who were hospitalized in intensive care unit in Alzahra hospital in Isfahan, 2013. Fifty patients were selected through convenient sampling and were randomly assigned into two groups of 25 people of intervention and control. Nutrition was done through infusion pump in intervention group and by bolus in control group. Gastric residual volume and diarrhea was assessed each four hours for four days. Data were gathered through checklist and were analyzed by SPSS18 using descriptive and inferential statistics including independent T-test, Fisher's exact test and repeated measures ANOVA. Results: The results showed that the mean of gastric residual volume in control group was more than the intervention group on the third day (p=0.04. Also, the mean of gastric residual volume did not show significant difference at different times in intervention group, but the mean of gastric residual volume was significantly increased in control group at different times (p=0.04. Fisher's exact test showed no significant difference between two groups concerning the diarrhea frequency. Conclusion: In nutritional support with continuous infusion method, gastric residual volume was not increased and gastric emptying rate was not diminished. Therefore, this method can be used as an appropriate nutritional support in intensive care unit.
Munch, G D W; Svendsen, J H; Damsgaard, R; Secher, N H; González-Alonso, J; Mortensen, S P
2014-01-15
In humans, maximal aerobic power (VO2 max ) is associated with a plateau in cardiac output (Q), but the mechanisms regulating the interplay between maximal heart rate (HRmax) and stroke volume (SV) are unclear. To evaluate the effect of tachycardia and elevations in HRmax on cardiovascular function and capacity during maximal exercise in healthy humans, 12 young male cyclists performed incremental cycling and one-legged knee-extensor exercise (KEE) to exhaustion with and without right atrial pacing to increase HR. During control cycling, Q and leg blood flow increased up to 85% of maximal workload (WLmax) and remained unchanged until exhaustion. SV initially increased, plateaued and then decreased before exhaustion (P rate pressure product and RAP (P heart can be paced to a higher HR than observed during maximal exercise, suggesting that HRmax and myocardial work capacity do not limit VO2 max in healthy individuals. A limited left ventricular filling and possibly altered contractility reduce SV during atrial pacing, whereas a plateau in LVFP appears to restrict Q close to VO2 max .
Beeping a Maximal Independent Set
Afek, Yehuda; Bar-Joseph, Ziv; Cornejo, Alejandro; Haeupler, Bernhard; Kuhn, Fabian
2012-01-01
We consider the problem of computing a maximal independent set (MIS) in an extremely harsh broadcast model that relies only on carrier sensing. The model consists of an anonymous broadcast network in which nodes have no knowledge about the topology of the network or even an upper bound on its size. Furthermore, it is assumed that an adversary chooses at which time slot each node wakes up. At each time slot a node can either beep, that is, emit a signal, or be silent. At a particular time slot, beeping nodes receive no feedback, while silent nodes can only differentiate between none of its neighbors beeping, or at least one of its neighbors beeping. We start by proving a lower bound that shows that in this model, it is not possible to locally converge to an MIS in sub-polynomial time. We then study four different relaxations of the model which allow us to circumvent the lower bound and find an MIS in polylogarithmic time. First, we show that if a polynomial upper bound on the network size is known, it is possi...
Maximal switchability of centralized networks
Vakulenko, Sergei; Morozov, Ivan; Radulescu, Ovidiu
2016-08-01
We consider continuous time Hopfield-like recurrent networks as dynamical models for gene regulation and neural networks. We are interested in networks that contain n high-degree nodes preferably connected to a large number of N s weakly connected satellites, a property that we call n/N s -centrality. If the hub dynamics is slow, we obtain that the large time network dynamics is completely defined by the hub dynamics. Moreover, such networks are maximally flexible and switchable, in the sense that they can switch from a globally attractive rest state to any structurally stable dynamics when the response time of a special controller hub is changed. In particular, we show that a decrease of the controller hub response time can lead to a sharp variation in the network attractor structure: we can obtain a set of new local attractors, whose number can increase exponentially with N, the total number of nodes of the nework. These new attractors can be periodic or even chaotic. We provide an algorithm, which allows us to design networks with the desired switching properties, or to learn them from time series, by adjusting the interactions between hubs and satellites. Such switchable networks could be used as models for context dependent adaptation in functional genetics or as models for cognitive functions in neuroscience.
A Maximally Supersymmetric Kondo Model
Harrison, Sarah; Kachru, Shamit; Torroba, Gonzalo; /Stanford U., Phys. Dept. /SLAC
2012-02-17
We study the maximally supersymmetric Kondo model obtained by adding a fermionic impurity to N = 4 supersymmetric Yang-Mills theory. While the original Kondo problem describes a defect interacting with a free Fermi liquid of itinerant electrons, here the ambient theory is an interacting CFT, and this introduces qualitatively new features into the system. The model arises in string theory by considering the intersection of a stack of M D5-branes with a stack of N D3-branes, at a point in the D3 worldvolume. We analyze the theory holographically, and propose a dictionary between the Kondo problem and antisymmetric Wilson loops in N = 4 SYM. We perform an explicit calculation of the D5 fluctuations in the D3 geometry and determine the spectrum of defect operators. This establishes the stability of the Kondo fixed point together with its basic thermodynamic properties. Known supergravity solutions for Wilson loops allow us to go beyond the probe approximation: the D5s disappear and are replaced by three-form flux piercing a new topologically non-trivial S3 in the corrected geometry. This describes the Kondo model in terms of a geometric transition. A dual matrix model reflects the basic properties of the corrected gravity solution in its eigenvalue distribution.
Maximal muscular vascular conductances during whole body upright exercise in humans
Calbet, J A L; Jensen-Urstad, M; Van Hall, Gerrit;
2004-01-01
That muscular blood flow may reach 2.5 l kg(-1) min(-1) in the quadriceps muscle has led to the suggestion that muscular vascular conductance must be restrained during whole body exercise to avoid hypotension. The main aim of this study was to determine the maximal arm and leg muscle vascular...... conductances (VC) during leg and arm exercise, to find out if the maximal muscular vasodilatory response is restrained during maximal combined arm and leg exercise. Six Swedish elite cross-country skiers, age (mean +/-s.e.m.) 24 +/- 2 years, height 180 +/- 2 cm, weight 74 +/- 2 kg, and maximal oxygen uptake...
D2-brane Chern-Simons theories: F-maximization = a-maximization
Fluder, Martin
2015-01-01
We study a system of N D2-branes probing a generic Calabi-Yau three-fold singularity in the presence of a non-zero quantized Romans mass n. We argue that the low-energy effective N = 2 Chern-Simons quiver gauge theory flows to a superconformal fixed point in the IR, and construct the dual AdS_4 solution in massive IIA supergravity. We compute the free energy F of the gauge theory on S^3 using localization. In the large N limit we find F = c(nN)^{1/3}a^{2/3}, where c is a universal constant and a is the a-function of the "parent" four-dimensional N = 1 theory on N D3-branes probing the same Calabi-Yau singularity. It follows that maximizing F over the space of admissible R-symmetries is equivalent to maximizing a for this class of theories. Moreover, we show that the gauge theory result precisely matches the holographic free energy of the supergravity solution, and provide a similar matching of the VEV of a BPS Wilson loop operator.
Carlbring, Per; Maurin, Tommy; Sjömark, Josefin; Maurin, Linda; Westling, Bengt E; Ekselius, Lisa; Cuijpers, Pim; Andersson, Gerhard
2011-01-01
Bibliotherapy is potentially effective in the treatment of panic disorder (PD). A still unanswered question is whether pacing is important. This study was designed to test whether there is a difference between being assigned a full book as therapy and receiving one individual chapter every week (i.e. pacing). A total of 28 participants were randomized to either 10 paced chapters or one book with 10 chapters. To maximize compliance, short weekly telephone calls were added in both conditions (M = 17.8 min, SD = 4.2). Both treatments showed promising results, with effects maintained up to 2 years and with within-group effect sizes (Cohen's d) between 0.95 and 1.11. Pretreatment ratings of credibility were positively correlated with the change scores at both posttest and 2-year follow-up for three panic measures. Pacing of text material in bibliotherapy for PD is not needed, and all material can be provided at once when the treatment is guided by a therapist.
Olaizola Ortega, María Norma; Valenciano Llovera, Federico
2012-01-01
This paper provides a new model of network formation that bridges the gap between the two benchmark models by Bala and Goyal, the one-way flow model, and the two-way flow model, and includes both as particular extreme cases. As in both benchmark models, in what we call an "asymmetric flow" network a link can be initiated unilaterally by any player with any other, and the flow through a link towards the player who supports it is perfect. Unlike those models, in the opposite direction there is ...
Yu, S.; Mathur, R.; Pleim, J.; Wong, D.; Gilliam, R.; Alapaty, K.; Zhao, C.; Liu, X.
2014-01-01
This study implemented first, second and glaciation aerosol indirect effects (AIE) on resolved clouds in the two-way coupled Weather Research and Forecasting Community Multiscale Air Quality (WRF–CMAQ) modeling system by including parameterizations for both cloud drop and ice number concentrations on the basis of CMAQ-predicted aerosol distributions and WRF meteorological conditions. The performance of the newly developed WRF–CMAQ model, with alternate Community Atmospheric Model (CAM) and Rapid Radiative Transfer Model for GCMs (RRTMG) radiation schemes, was evaluated with observations from the Clouds and the See http://ceres.larc.nasa.gov/. Earth's Radiant Energy System (CERES) satellite and surface monitoring networks (AQS, IMPROVE, CASTNET, STN, and PRISM) over the continental US (CONUS) (12 km resolution) and eastern Texas (4 km resolution) during August and September of 2006. The results at the Air Quality System (AQS) surface sites show that in August, the normalized mean bias (NMB) values for PM_{2.5} over the eastern US (EUS) and the western US (WUS) are 5.3% (-0.1%) and 0.4% (-5.2%) for WRF–CMAQ/CAM (WRF–CMAQ/RRTMG), respectively. The evaluation of PM_{2.5} chemical composition reveals that in August, WRF–CMAQ/CAM (WRF–CMAQ/RRTMG) consistently underestimated the observed SO_{4}^{2-} by -23.0% (-27.7%), -12.5% (-18.9%) and -7.9% (-14.8%) over the EUS at the Clean Air Status Trends Network (CASTNET), Interagency Monitoring of Protected Visual Environments (IMPROVE) and Speciated Trends Network (STN) sites, respectively. Both configurations (WRF–CMAQ/CAM, WRF–CMAQ/RRTMG) overestimated the observed mean organic carbon (OC), elemental carbon (EC) and and total carbon (TC) concentrations over the EUS in August at the IMPROVE sites. Both configurations generally underestimated the cloud field (shortwave cloud forcing, SWCF) over the CONUS in August due
Theory Transmission:from One-way to Two-way%从理论的（单向）旅行到（双向）对话
王宁
2016-01-01
长期以来，中国的文学理论批评始终笼罩在西方理论的阴影之下，西方的理论可以通过翻译的中介长驱直入进入中国的文学理论批评话语中。虽然理论的旅行会发生某种变异，但这种旅行和变异长期以来却一直是单向的，也即从西方到东方。美国文学理论家希利斯•米勒最近同时在西方和中国出版的一本演讲集则一改这种理论单向旅行的路径，加进了与中国学者对话的部分，这应该是一个可喜的开端。本文作者认为，中国经济的飞速发展使得中国文化和文学理论走向世界也提到了中国学者的议事日程上。在这方面，米勒与中国学者张江的对话可以说预示了这种理论双向旅行的开始，但是作为中国学者，我们应该积极主动地与西方以及国际主流学者进行交流和对话。也许翻译的中介会使得中国的理论在西方世界发生变异，但是如果中西文论的对话能够持续进行下去，那就是值得的。%For a long time, China’s literary theory and criticism was overshadowed by Western theories. Through translation, Western theories have a clear path to China’s literary critical discourse. There are changes and aberrance during the transmission, but the transmission and aberrance have long been unidirectional: from West to East. J. Hillis Miller, an American literary critic recently published a collection of speeches in the West and China at the same time. The theories do not travel in a one-way system in this book, to which he adds the dialogues between Western theorists and their Chinese counterparts. This marks a good beginning. In this paper, the author holds that the rapid development of Chinese economy allows Chinese scholars to bring Chinese culture and literary theories to the world. In this regard, Miller’s dialogue with Chinese scholar ZHANG Jiang probably signifies the beginning of a two-way transmission of theories
Cardiovascular consequences of bed rest: effect on maximal oxygen uptake
Convertino, V. A.
1997-01-01
Maximal oxygen uptake (VO2max) is reduced in healthy individuals confined to bed rest, suggesting it is independent of any disease state. The magnitude of reduction in VO2max is dependent on duration of bed rest and the initial level of aerobic fitness (VO2max), but it appears to be independent of age or gender. Bed rest induces an elevated maximal heart rate which, in turn, is associated with decreased cardiac vagal tone, increased sympathetic catecholamine secretion, and greater cardiac beta-receptor sensitivity. Despite the elevation in heart rate, VO2max is reduced primarily from decreased maximal stroke volume and cardiac output. An elevated ejection fraction during exercise following bed rest suggests that the lower stroke volume is not caused by ventricular dysfunction but is primarily the result of decreased venous return associated with lower circulating blood volume, reduced central venous pressure, and higher venous compliance in the lower extremities. VO2max, stroke volume, and cardiac output are further compromised by exercise in the upright posture. The contribution of hypovolemia to reduced cardiac output during exercise following bed rest is supported by the close relationship between the relative magnitude (% delta) and time course of change in blood volume and VO2max during bed rest, and also by the fact that retention of plasma volume is associated with maintenance of VO2max after bed rest. Arteriovenous oxygen difference during maximal exercise is not altered by bed rest, suggesting that peripheral mechanisms may not contribute significantly to the decreased VO2max. However reduction in baseline and maximal muscle blood flow, red blood cell volume, and capillarization in working muscles represent peripheral mechanisms that may contribute to limited oxygen delivery and, subsequently, lowered VO2max. Thus, alterations in cardiac and vascular functions induced by prolonged confinement to bed rest contribute to diminution of maximal oxygen uptake
伍斌; 谢红付; 李罗丝; 张江林; 李建国
2006-01-01
[Objective] To investigate the effects of Oxymatrine (OMT) on mouse lymphocyte proliferation stimulated by Con A, explore the mechanism of the effects of OMT on the immune system and provide theoretical and experimental evidence for the clinical application of OMT in treating immune-related diseases. [Methods] CFDA-SE staining and flow cytometry were used to detect the fluorescence intensity of lymphocytes after stimulated by polyclonal stimulators Con A and OMT. Related softwares were used to analyze the effects of OMT on mouse lymphocyte proliferation. [Results] OMT has the function to restrain the proliferation of lymphocyte of mouse depended on its concentration with 500, 125 and 31 μg/mL in substrate, but 16, 8, 4, 2 μg/mL concentration, it improves the proliferation of T lymphocytes of mouse's lymph node, the dependence on its concentration is not significant. [Conclusions ] 1. Both CFDA-SE dyeing and flow cytometer were reliable tools to analyze lymphocyte proliferation. 2. OMT has the two-ways effects on T lymphocyte proliferation in mouse lymph node stimulated by Con A.%目的检测氧化苦参碱(Oxymatrine,OMT)对刀豆蛋白A(Con A)刺激的小鼠淋巴结T细胞增殖的影响,探讨OMT对免疫系统的作用机制,为临床用OMT治疗免疫相关性疾病提供理论和实验依据.方法利用CFDA-SE染色,流式细胞术检测淋巴细胞在多克隆刺激剂Con A和OMT的共同作同下荧光强度的变化,并应用CELLQuest软件分析OMT对小鼠淋巴结T细胞增殖的影响程度.结果 500、125和31μg/mLOMT对小鼠淋巴结T细胞增殖呈剂量依赖性抑制,而16、8、4、2μg/mL OMT对小鼠淋巴结T细胞增殖起促进作用,但其剂量依赖关系不明显.结论 CFDA-SE染色和流式细胞术是分析淋巴细胞增殖的有力工具:OMT对小鼠淋巴结T细胞的增殖呈双向作用.
Maximal inequalities for demimartingales and their applications
WANG XueJun; HU ShuHe
2009-01-01
In this paper,we establish some maximal inequalities for demimartingales which generalize and improve the results of Christofides.The maximal inequalities for demimartingales are used as key inequalities to establish other results including Doob's type maximal inequality for demimartingales,strong laws of large numbers and growth rate for demimartingales and associated random variables.At last,we give an equivalent condition of uniform integrability for demisubmartingales.
Maximal inequalities for demimartingales and their applications
无
2009-01-01
In this paper, we establish some maximal inequalities for demimartingales which generalize and improve the results of Christofides. The maximal inequalities for demimartingales are used as key inequalities to establish other results including Doob’s type maximal inequality for demimartingales, strong laws of large numbers and growth rate for demimartingales and associated random variables. At last, we give an equivalent condition of uniform integrability for demisubmartingales.
Task-oriented maximally entangled states
Agrawal, Pankaj; Pradhan, B, E-mail: agrawal@iopb.res.i, E-mail: bpradhan@iopb.res.i [Institute of Physics, Sachivalaya Marg, Bhubaneswar, Orissa 751 005 (India)
2010-06-11
We introduce the notion of a task-oriented maximally entangled state (TMES). This notion depends on the task for which a quantum state is used as the resource. TMESs are the states that can be used to carry out the task maximally. This concept may be more useful than that of a general maximally entangled state in the case of a multipartite system. We illustrate this idea by giving an operational definition of maximally entangled states on the basis of communication tasks of teleportation and superdense coding. We also give examples and a procedure to obtain such TMESs for n-qubit systems.
Inflation in maximal gauged supergravities
Kodama, Hideo [Theory Center, KEK,Tsukuba 305-0801 (Japan); Department of Particles and Nuclear Physics,The Graduate University for Advanced Studies,Tsukuba 305-0801 (Japan); Nozawa, Masato [Dipartimento di Fisica, Università di Milano, and INFN, Sezione di Milano,Via Celoria 16, 20133 Milano (Italy)
2015-05-18
We discuss the dynamics of multiple scalar fields and the possibility of realistic inflation in the maximal gauged supergravity. In this paper, we address this problem in the framework of recently discovered 1-parameter deformation of SO(4,4) and SO(5,3) dyonic gaugings, for which the base point of the scalar manifold corresponds to an unstable de Sitter critical point. In the gauge-field frame where the embedding tensor takes the value in the sum of the 36 and 36’ representations of SL(8), we present a scheme that allows us to derive an analytic expression for the scalar potential. With the help of this formalism, we derive the full potential and gauge coupling functions in analytic forms for the SO(3)×SO(3)-invariant subsectors of SO(4,4) and SO(5,3) gaugings, and argue that there exist no new critical points in addition to those discovered so far. For the SO(4,4) gauging, we also study the behavior of 6-dimensional scalar fields in this sector near the Dall’Agata-Inverso de Sitter critical point at which the negative eigenvalue of the scalar mass square with the largest modulus goes to zero as the deformation parameter s approaches a critical value s{sub c}. We find that when the deformation parameter s is taken sufficiently close to the critical value, inflation lasts more than 60 e-folds even if the initial point of the inflaton allows an O(0.1) deviation in Planck units from the Dall’Agata-Inverso critical point. It turns out that the spectral index n{sub s} of the curvature perturbation at the time of the 60 e-folding number is always about 0.96 and within the 1σ range n{sub s}=0.9639±0.0047 obtained by Planck, irrespective of the value of the η parameter at the critical saddle point. The tensor-scalar ratio predicted by this model is around 10{sup −3} and is close to the value in the Starobinsky model.
Ways to maximize effective collections.
Spears, Tracy L
2009-01-01
Medical practices across the country face a variety of collection challenges, especially when considering the condition of today's economy. It is now more important than ever for a practice to establish proactive collection procedures and learn the keys to minimizing collection problems. This starts with educating patients about your payment terms prior to appointments and educating your staff to be aware of early warning signs when an account could become a problem. Taking steps that lead to quick resolution, while retaining patients, is a vital component to increased cash flow and fewer aging accounts in receivables. Careful review of your practice's policies on billing and collections can lead to a greater knowledge on how healthy the practice really is. This article provides key strategies that will help streamline your billing and collections process and recover money owed to you while maintaining those ever so important patient relationships.
常浩; 荣喜民
2011-01-01
研究完全市场下基于二次效用最大化的带有随机资金流的动态投资组合选择问题,其中假设无风险利率、股票收益率和波动率矩阵都是一致有界随机过程.通过应用线性二次控制方法和向后随机微分方程理论得到了最优投资组合的解析表达式.%This paper is concerned with a dynamic portfolio selection problem with stochastic cash flow in a complete financial market for quadratic utility maximization, in which interest rate, appreciation rates and volatility coefficients are allowed to be uniformly bounded stochastic processes. The optimal portfolio in the explicit forms is constructed via linear quadratic control technique and results from backward stochastic differential equations (BS-Des) theory.
A Data-Based Approach to Social Influence Maximization
Goyal, Amit; Lakshmanan, Laks V S
2011-01-01
Influence maximization is the problem of finding a set of users in a social network, such that by targeting this set, one maximizes the expected spread of influence in the network. Most of the literature on this topic has focused exclusively on the social graph, overlooking historical data, i.e., traces of past action propagations. In this paper, we study influence maximization from a novel data-based perspective. In particular, we introduce a new model, which we call credit distribution, that directly leverages available propagation traces to learn how influence flows in the network and uses this to estimate expected influence spread. Our approach also learns the different levels of influenceability of users, and it is time-aware in the sense that it takes the temporal nature of influence into account. We show that influence maximization under the credit distribution model is NP-hard and that the function that defines expected spread under our model is submodular. Based on these, we develop an approximation ...
Computing Maximally Supersymmetric Scattering Amplitudes
Stankowicz, James Michael, Jr.
This dissertation reviews work in computing N = 4 super-Yang--Mills (sYM) and N = 8 maximally supersymmetric gravity (mSUGRA) scattering amplitudes in D = 4 spacetime dimensions in novel ways. After a brief introduction and overview in Ch. 1, the various techniques used to construct amplitudes in the remainder of the dissertation are discussed in Ch. 2. This includes several new concepts such as d log and pure integrand bases, as well as how to construct the amplitude using exactly one kinematic point where it vanishes. Also included in this chapter is an outline of the Mathematica package on shell diagrams and numerics.m (osdn) that was developed for the computations herein. The rest of the dissertation is devoted to explicit examples. In Ch. 3, the starting point is tree-level sYM amplitudes that have integral representations with residues that obey amplitude relations. These residues are shown to have corresponding residue numerators that allow a double copy prescription that results in mSUGRA residues. In Ch. 4, the two-loop four-point sYM amplitude is constructed in several ways, showcasing many of the techniques of Ch. 2; this includes an example of how to use osdn. The two-loop five-point amplitude is also presented in a pure integrand representation with comments on how it was constructed from one homogeneous cut of the amplitude. On-going work on the two-loop n-point amplitude is presented at the end of Ch. 4. In Ch. 5, the three-loop four-point amplitude is presented in the d log representation and in the pure integrand representation. In Ch. 6, there are several examples of four- through seven-loop planar diagrams that illustrate how considerations of the singularity structure of the amplitude underpin dual-conformal invariance. Taken with the previous examples, this is additional evidence that the structure known to exist in the planar sector extends to the full theory. At the end of this chapter is a proof that all mSUGRA amplitudes have a pole at
Are all maximally entangled states pure?
Cavalcanti, D; Terra-Cunha, M O
2005-01-01
In this Letter we study if all maximally entangled states are pure through several entanglement monotones. Our conclusions allow us to generalize the idea of monogamy of entanglement. Then we propose a polygamy of entanglement, which express that if a general multipartite state is maximally entangled it is necessarily factorized by any other system.
Sampling and Representation Complexity of Revenue Maximization
Dughmi, Shaddin; Han, Li; Nisan, Noam
2014-01-01
We consider (approximate) revenue maximization in auctions where the distribution on input valuations is given via "black box" access to samples from the distribution. We observe that the number of samples required -- the sample complexity -- is tightly related to the representation complexity of an approximately revenue-maximizing auction. Our main results are upper bounds and an exponential lower bound on these complexities.
Lisonek, Petr
1996-01-01
our classifications confirmthe maximality of previously known sets, the results in E^7 and E^8are new. Their counterpart in dimension larger than 10is a set of unit vectors with only two values of inner products in the Lorentz space R^{d,1}.The maximality of this set again follows from a bound due...
An ethical justification of profit maximization
Koch, Carsten Allan
2010-01-01
In much of the literature on business ethics and corporate social responsibility, it is more or less taken for granted that attempts to maximize profits are inherently unethical. The purpose of this paper is to investigate whether an ethical argument can be given in support of profit maximizing b...
Alternative trailer configurations for maximizing payloads
Jason D. Thompson; Dana Mitchell; John Klepac
2017-01-01
In order for harvesting contractors to stay ahead of increasing costs, it is imperative that they employ all options to maximize productivity and efficiency. Transportation can account for half the cost to deliver wood to a mill. Contractors seek to maximize truck payload to increase productivity. The Forest Operations Research Unit, Southern Research Station, USDA...
Cohomology of Weakly Reducible Maximal Triangular Algebras
董浙; 鲁世杰
2000-01-01
In this paper, we introduce the concept of weakly reducible maximal triangular algebras φwhich form a large class of maximal triangular algebras. Let B be a weakly closed algebra containing 5φ, we prove that the cohomology spaces Hn(φ, B) (n≥1) are trivial.
Inclusive fitness maximization: An axiomatic approach.
Okasha, Samir; Weymark, John A; Bossert, Walter
2014-06-07
Kin selection theorists argue that evolution in social contexts will lead organisms to behave as if maximizing their inclusive, as opposed to personal, fitness. The inclusive fitness concept allows biologists to treat organisms as akin to rational agents seeking to maximize a utility function. Here we develop this idea and place it on a firm footing by employing a standard decision-theoretic methodology. We show how the principle of inclusive fitness maximization and a related principle of quasi-inclusive fitness maximization can be derived from axioms on an individual׳s 'as if preferences' (binary choices) for the case in which phenotypic effects are additive. Our results help integrate evolutionary theory and rational choice theory, help draw out the behavioural implications of inclusive fitness maximization, and point to a possible way in which evolution could lead organisms to implement it. Copyright © 2014 Elsevier Ltd. All rights reserved.
Maximal Hypersurfaces in Spacetimes with Translational Symmetry
Bulawa, Andrew
2016-01-01
We consider four-dimensional vacuum spacetimes which admit a free isometric spacelike R-action. Taking a quotient with respect to the R-action produces a three-dimensional quotient spacetime. We establish several results regarding maximal hypersurfaces (spacelike hypersurfaces of zero mean curvature) in quotient spacetimes. First, we show that complete noncompact maximal hypersurfaces must either be flat cylinders S^1 x R or conformal to the Euclidean plane. Second, we establish a positive mass theorem for certain maximal hypersurfaces. Finally, while it is meaningful to use a bounded lapse when adopting the maximal hypersurface gauge condition in the four-dimensional (asymptotically flat) setting, it is shown here that nontrivial quotient spacetimes admit the maximal hypersurface gauge only with an unbounded lapse.
Zhai, Liming; Luo, Yongyao; Wang, Zhengwei; Liu, Xin
2016-01-01
The thermal elastic hydro dynamic (TEHD) lubrication analysis for the thrust bearing is usually conducted by combining Reynolds equation with finite element analysis (FEA). But it is still a problem to conduct the computation by combining computational fluid dynamics (CFD) and FEA which can simulate the TEHD more accurately. In this paper, by using both direct and separate coupled solutions together, steady TEHD lubrication considering the viscosity-temperature effect for a bidirectional thrust bearing in a pump-turbine unit is simulated combining a 3D CFD model for the oil film with a 3D FEA model for the pad and mirror plate. Cyclic symmetry condition is used in the oil film flow as more reasonable boundary conditions which avoids the oil temperature assumption at the leading and trailing edge. Deformations of the pad and mirror plate are predicted and discussed as well as the distributions of oil film thickness, pressure, temperature. The predicted temperature shows good agreement with measurements, while the pressure shows a reasonable distribution comparing with previous studies. Further analysis of the three-coupled-field reveals the reason of the high pressure and high temperature generated in the film. Finally, the influence of rotational speed of the mirror plate on the lubrication characteristics is illustrated which shows the thrust load should be balanced against the oil film temperature and pressure in optimized designs. This research proposes a thrust bearing computation method by combining CFD and FEA which can do the TEHD analysis more accurately.
氧化苦参碱对骨髓来源细胞生长的双向调节作用%The Two-Ways Regulation of Oxymatrine on Cells Derived from Bone Marrow
郝彩芹; 李静; 李兴玉; 刘新利; 许燕; 张吉旺
2013-01-01
目的:观察氧化苦参碱(oxymatrine,OMT)对骨髓来源细胞增殖的影响.方法:应用MTr比色法、流式细胞仪检测法、集落形成法和免疫细胞活性测定等方法,检测OMT对白血病细胞K562的抑制作用;骨髓造血干细胞的集落形成实验和脾细胞对肿瘤细胞的杀伤的生物活性试验,检测OMT对小鼠免疫和造血的影响.结果:(1)不同浓度的OMT可明显抑制白血病细胞K562细胞的增殖、集落形成,导致细胞凋亡(P＜0.05),且作用呈浓度依赖性.(2)OMT可以促进小鼠骨髓粒系造血,且在0.2475 mg/mL时达到峰值.(3)OMT可抑制小鼠的免疫功能.结论:OMT可抑制白血病K562细胞的增殖并诱导其凋亡,同时抑制小鼠的免疫功能,促进小鼠骨髓CFU-GM的形成,表现出对骨髓来源细胞生长的双向调节作用.%Objective:To study the effect of Oxymatrine on the proliferation of cells derived from bone marrow.Methods:MTT assay,flow cytometry analysis,cell colony formation assay and cell immune activity determination method were used to study the effect of Oxymatrine on Chronic myeloid leukemia cell line K562.Cell colony formation assay of Bone marrow hematopoietic stem cells and killing effect of spleen cells on tumor cells were used to detect the influence of Oxymatrine on immune and hematopoietic system of mouse.Results:Oxymatrine significantly inhibited the proliferation of K562 cells,induced the apoptosis and inhibited the formation of cell colony in a concentration dependent manner.Meanwhile,it also suppressed the immune function and promote the hematopoietic function of mouse.Conclusion:Oxymatrine could inhibit the proliferation and induce the apoptosis in K562 cells,meanwhile suppress the immune function of mouse and promote the formation of CFU-GM of bone marrow of mouse,which showed two-way regulation on cells derived from bone marrow.
Are all maximally entangled states pure?
Cavalcanti, D.; Brandão, F. G. S. L.; Terra Cunha, M. O.
2005-10-01
We study if all maximally entangled states are pure through several entanglement monotones. In the bipartite case, we find that the same conditions which lead to the uniqueness of the entropy of entanglement as a measure of entanglement exclude the existence of maximally mixed entangled states. In the multipartite scenario, our conclusions allow us to generalize the idea of the monogamy of entanglement: we establish the polygamy of entanglement, expressing that if a general state is maximally entangled with respect to some kind of multipartite entanglement, then it is necessarily factorized of any other system.
An ethical justification of profit maximization
Koch, Carsten Allan
2010-01-01
In much of the literature on business ethics and corporate social responsibility, it is more or less taken for granted that attempts to maximize profits are inherently unethical. The purpose of this paper is to investigate whether an ethical argument can be given in support of profit maximizing...... behaviour. It is argued that some form of consequential ethics must be applied, and that both profit seeking and profit maximization can be defended from a rule-consequential point of view. It is noted, however, that the result does not apply unconditionally, but requires that certain form of profit (and...
Robust utility maximization in a discontinuous filtration
Jeanblanc, Monique; Ngoupeyou, Armand
2012-01-01
We study a problem of utility maximization under model uncertainty with information including jumps. We prove first that the value process of the robust stochastic control problem is described by the solution of a quadratic-exponential backward stochastic differential equation with jumps. Then, we establish a dynamic maximum principle for the optimal control of the maximization problem. The characterization of the optimal model and the optimal control (consumption-investment) is given via a forward-backward system which generalizes the result of Duffie and Skiadas (1994) and El Karoui, Peng and Quenez (2001) in the case of maximization of recursive utilities including model with jumps.
Dinç, Erdal; Ertekin, Zehra Ceren; Büker, Eda
2016-09-01
Two-way and three-way calibration models were applied to ultra high performance liquid chromatography with photodiode array data with coeluted peaks in the same wavelength and time regions for the simultaneous quantitation of ciprofloxacin and ornidazole in tablets. The chromatographic data cube (tensor) was obtained by recording chromatographic spectra of the standard and sample solutions containing ciprofloxacin and ornidazole with sulfadiazine as an internal standard as a function of time and wavelength. Parallel factor analysis and trilinear partial least squares were used as three-way calibrations for the decomposition of the tensor, whereas three-way unfolded partial least squares was applied as a two-way calibration to the unfolded dataset obtained from the data array of ultra high performance liquid chromatography with photodiode array detection. The validity and ability of two-way and three-way analysis methods were tested by analyzing validation samples: synthetic mixture, interday and intraday samples, and standard addition samples. Results obtained from two-way and three-way calibrations were compared to those provided by traditional ultra high performance liquid chromatography. The proposed methods, parallel factor analysis, trilinear partial least squares, unfolded partial least squares, and traditional ultra high performance liquid chromatography were successfully applied to the quantitative estimation of the solid dosage form containing ciprofloxacin and ornidazole.
Milne, Roger L; Herranz, Jesús; Michailidou, Kyriaki
2014-01-01
Part of the substantial unexplained familial aggregation of breast cancer may be due to interactions between common variants, but few studies have had adequate statistical power to detect interactions of realistic magnitude. We aimed to assess all two-way interactions in breast cancer susceptibil...
杨鼎文
2012-01-01
Appreciation can be divided into one-way to appreciate and two-way appreciation, one-way appreciation is the appreciation of the public of public figures, two-way to enjoy the appreciation of the interaction between people. Appreciate the subject that applied to ＂watch＂ to the object that is, by those who ＂watch＂ two-way appreciation of the subject and object In addition to the interactive, interchangeable. Two-way appreciation the role in the establishment of a harmonious companion relations, promotion and probation. Children to appreciate other people＇s form of expression, language appreciation, acceptance and recognition. Active channels to promote two-way appreciation of the children： theme activities, literature appreciation, democratic election activities, cooperative games, activities.%欣赏可以分为单向欣赏和双向欣赏，单向欣赏是指公众对公众人物的欣赏，双向欣赏为有交往的人与人之间的欣赏。欣赏的主体即施“欣赏”者，客体即受“欣赏”者，双向欣赏的主体和客体除了可以互动，还是可以互换的。双向欣赏在建立和谐同伴关系中有促进和感化的作用。幼儿欣赏他人的表现形式有语言的赞赏、接纳和认同。促进幼儿双向欣赏的活动通道有：系统的主题活动、文学欣赏活动、民主选举活动、合作游戏活动等。
HEALTH INSURANCE: CONTRIBUTIONS AND REIMBURSEMENT MAXIMAL
HR Division
2000-01-01
Affected by both the salary adjustment index on 1.1.2000 and the evolution of the staff members and fellows population, the average reference salary, which is used as an index for fixed contributions and reimbursement maximal, has changed significantly. An adjustment of the amounts of the reimbursement maximal and the fixed contributions is therefore necessary, as from 1 January 2000.Reimbursement maximalThe revised reimbursement maximal will appear on the leaflet summarising the benefits for the year 2000, which will soon be available from the divisional secretariats and from the AUSTRIA office at CERN.Fixed contributionsThe fixed contributions, applicable to some categories of voluntarily insured persons, are set as follows (amounts in CHF for monthly contributions):voluntarily insured member of the personnel, with complete coverage:815,- (was 803,- in 1999)voluntarily insured member of the personnel, with reduced coverage:407,- (was 402,- in 1999)voluntarily insured no longer dependent child:326,- (was 321...
Maximizing throughput by evaluating critical utilization paths
Weeda, P.J.
1991-01-01
Recently the relationship between batch structure, bottleneck machine and maximum throughput has been explored for serial, convergent and divergent process configurations consisting of two machines and three processes. In three of the seven possible configurations a multiple batch structure maximize
Relationship between maximal exercise parameters and individual ...
Relationship between maximal exercise parameters and individual time trial ... It is widely accepted that the ventilatory threshold (VT) is an important ... This study investigated whether the physiological responses during a 20km time trial (TT) ...
Simple technique for maximal thoracic muscle harvest.
Marshall, M Blair; Kaiser, Larry R; Kucharczuk, John C
2004-04-01
We present a modification of technique for standard muscle flap harvest, the placement of cutaneous traction sutures. This technique allows for maximal dissection of the thoracic muscles even through minimal incisions. Through improved exposure and traction, complete dissection of the muscle bed can be performed and the tissue obtained maximized. Because more muscle bulk is obtained with this technique, the need for a second muscle may be prevented.
MAXIMAL POINTS OF A REGULAR TRUTH FUNCTION
Every canonical linearly separable truth function is a regular function, but not every regular truth function is linearly separable. The most...promising method of determining which of the regular truth functions are linearly separable r quires finding their maximal and minimal points. In this...report is developed a quick, systematic method of finding the maximal points of any regular truth function in terms of its arithmetic invariants. (Author)
Maximal Subgroups of Skew Linear Groups
M. Mahdavi-Hezavehi
2002-01-01
Let D be an infinite division algebra of finite dimension over its centre Z(D) = F, and n a positive integer. The structure of maximal subgroups of skew linear groups are investigated. In particular, assume N is a normal subgroup of GLn(D) and M is a maximal subgroup of N containing Z(N). It is shown that if M/Z(N) is finite, then N is central.
Additive Approximation Algorithms for Modularity Maximization
Kawase, Yasushi; Matsui, Tomomi; Miyauchi, Atsushi
2016-01-01
The modularity is a quality function in community detection, which was introduced by Newman and Girvan (2004). Community detection in graphs is now often conducted through modularity maximization: given an undirected graph $G=(V,E)$, we are asked to find a partition $\\mathcal{C}$ of $V$ that maximizes the modularity. Although numerous algorithms have been developed to date, most of them have no theoretical approximation guarantee. Recently, to overcome this issue, the design of modularity max...
Maximal Frequent Itemset Generation Using Segmentation Apporach
M.Rajalakshmi
2011-09-01
Full Text Available Finding frequent itemsets in a data source is a fundamental operation behind Association Rule Mining.Generally, many algorithms use either the bottom-up or top-down approaches for finding these frequentitemsets. When the length of frequent itemsets to be found is large, the traditional algorithms find all thefrequent itemsets from 1-length to n-length, which is a difficult process. This problem can be solved bymining only the Maximal Frequent Itemsets (MFS. Maximal Frequent Itemsets are frequent itemsets whichhave no proper frequent superset. Thus, the generation of only maximal frequent itemsets reduces thenumber of itemsets and also time needed for the generation of all frequent itemsets as each maximal itemsetof length m implies the presence of 2m-2 frequent itemsets. Furthermore, mining only maximal frequentitemset is sufficient in many data mining applications like minimal key discovery and theory extraction. Inthis paper, we suggest a novel method for finding the maximal frequent itemset from huge data sourcesusing the concept of segmentation of data source and prioritization of segments. Empirical evaluationshows that this method outperforms various other known methods.
Natural selection and the maximization of fitness.
Birch, Jonathan
2016-08-01
The notion that natural selection is a process of fitness maximization gets a bad press in population genetics, yet in other areas of biology the view that organisms behave as if attempting to maximize their fitness remains widespread. Here I critically appraise the prospects for reconciliation. I first distinguish four varieties of fitness maximization. I then examine two recent developments that may appear to vindicate at least one of these varieties. The first is the 'new' interpretation of Fisher's fundamental theorem of natural selection, on which the theorem is exactly true for any evolving population that satisfies some minimal assumptions. The second is the Formal Darwinism project, which forges links between gene frequency change and optimal strategy choice. In both cases, I argue that the results fail to establish a biologically significant maximization principle. I conclude that it may be a mistake to look for universal maximization principles justified by theory alone. A more promising approach may be to find maximization principles that apply conditionally and to show that the conditions were satisfied in the evolution of particular traits.
Welfare-maximizing and revenue-maximizing tariffs with a few domestic firms
Bruno Larue; Jean-Philippe Gervais
2002-01-01
In this paper we compare the orthodox optimal tariff formula with the appropriate welfare-maximizing tariff when there are a few producing or importing firms. The welfare-maximizing tariff can be very low, voire negative in some cases, while in others it can even exceed the maximum-revenue tariff. The relationship between the welfare-maximizing tariff and the number of firms need not be monotonically increasing, because the tariff is not strictly used to internalize terms of trade externality...
Maximizing Complementary Quantities by Projective Measurements
M. Souza, Leonardo A.; Bernardes, Nadja K.; Rossi, Romeu
2017-04-01
In this work, we study the so-called quantitative complementarity quantities. We focus in the following physical situation: two qubits ( q A and q B ) are initially in a maximally entangled state. One of them ( q B ) interacts with a N-qubit system ( R). After the interaction, projective measurements are performed on each of the qubits of R, in a basis that is chosen after independent optimization procedures: maximization of the visibility, the concurrence, and the predictability. For a specific maximization procedure, we study in detail how each of the complementary quantities behave, conditioned on the intensity of the coupling between q B and the N qubits. We show that, if the coupling is sufficiently "strong," independent of the maximization procedure, the concurrence tends to decay quickly. Interestingly enough, the behavior of the concurrence in this model is similar to the entanglement dynamics of a two qubit system subjected to a thermal reservoir, despite that we consider finite N. However, the visibility shows a different behavior: its maximization is more efficient for stronger coupling constants. Moreover, we investigate how the distinguishability, or the information stored in different parts of the system, is distributed for different couplings.
李玮; 丁长文; 杨霖
2016-01-01
The performance of amplify-and-forward based two-way relay network is analyzed in combina-tion with energy harvesting technology. According to the end-to-end signal-to-noise ratio( SNR) balan-cing criterion,the optimal power allocation of two sources and the optimal energy harvesting proportion of the single selected relay are derived. Simulation results show that the proposed method can achieve the best performance. Comparison shows that energy harvesting two-way relay communication network has a higher achievable transmission rate than conventional two-way relay network.%结合能量收集技术，研究了放大转发双向中继网络的系统性能。基于双向中继系统中的两个端到端信噪比平衡准则，推导出了单中继选择情况下信源最优的功率分配方案和中继最优的能量收集比例。仿真结果证明所提方法能够实现最好的系统性能。通过比较发现，能量收集双向中继网络比传统双向中继网络能够实现更高的传输速率。
Quantum theory allows for absolute maximal contextuality
Amaral, Barbara; Cunha, Marcelo Terra; Cabello, Adán
2015-12-01
Contextuality is a fundamental feature of quantum theory and a necessary resource for quantum computation and communication. It is therefore important to investigate how large contextuality can be in quantum theory. Linear contextuality witnesses can be expressed as a sum S of n probabilities, and the independence number α and the Tsirelson-like number ϑ of the corresponding exclusivity graph are, respectively, the maximum of S for noncontextual theories and for the theory under consideration. A theory allows for absolute maximal contextuality if it has scenarios in which ϑ /α approaches n . Here we show that quantum theory allows for absolute maximal contextuality despite what is suggested by the examination of the quantum violations of Bell and noncontextuality inequalities considered in the past. Our proof is not constructive and does not single out explicit scenarios. Nevertheless, we identify scenarios in which quantum theory allows for almost-absolute-maximal contextuality.
The maximal process of nonlinear shot noise
Eliazar, Iddo; Klafter, Joseph
2009-05-01
In the nonlinear shot noise system-model shots’ statistics are governed by general Poisson processes, and shots’ decay-dynamics are governed by general nonlinear differential equations. In this research we consider a nonlinear shot noise system and explore the process tracking, along time, the system’s maximal shot magnitude. This ‘maximal process’ is a stationary Markov process following a decay-surge evolution; it is highly robust, and it is capable of displaying both a wide spectrum of statistical behaviors and a rich variety of random decay-surge sample-path trajectories. A comprehensive analysis of the maximal process is conducted, including its Markovian structure, its decay-surge structure, and its correlation structure. All results are obtained analytically and in closed-form.