WorldWideScience

Sample records for two-lane two-way rural

  1. Assisted overtaking: an assessment of overtaking on two-lane rural roads

    NARCIS (Netherlands)

    Hegeman, G.

    2008-01-01

    At the start of the 21st century overtaking on two-lane rural roads is a major traffic safety problem. However, this dissertation research demonstrates that most drivers are perfectly able to safely perform these manoeuvres. Their time spent in the left lane is about eight seconds. Preparing subtask

  2. Assisted overtaking: an assessment of overtaking on two-lane rural roads

    NARCIS (Netherlands)

    Hegeman, G.

    2008-01-01

    At the start of the 21st century overtaking on two-lane rural roads is a major traffic safety problem. However, this dissertation research demonstrates that most drivers are perfectly able to safely perform these manoeuvres. Their time spent in the left lane is about eight seconds. Preparing

  3. Influence of deficiencies in traffic control devices in crashes on two-lane rural roads.

    Science.gov (United States)

    López, Griselda; de Oña, Juan; Garach, Laura; Baena, Leticia

    2016-11-01

    One of the main objectives of all public administrations is reducing traffic crashes. To this end, Road Safety Inspections (RSI) stand out as a key measure. Signaling roads is one of the foremost tasks of RSI. A road that is improperly or poorly signaled can lead to incorrect placement or maneuvers of vehicles and ambiguous situations that can increase the risk of crashes. This paper analyses the relationship between road crashes in two-lane rural highways and certain deficiencies in signaling. The results show that deficiencies such as "incomplete removal of road works markings" or "no guide sign or in incorrect position" are the ones associated with a higher probability of crashes in two-lane rural highways. In view of these results, governmental agencies should verify that the original conditions of a highway are re-established after any construction work is completed. They should also continuously follow up on the signaling of this type of highway in order to maintain optimal conditions.

  4. Evaluating the safety risk of roadside features for rural two-lane roads using reliability analysis.

    Science.gov (United States)

    Jalayer, Mohammad; Zhou, Huaguo

    2016-08-01

    The severity of roadway departure crashes mainly depends on the roadside features, including the sideslope, fixed-object density, offset from fixed objects, and shoulder width. Common engineering countermeasures to improve roadside safety include: cross section improvements, hazard removal or modification, and delineation. It is not always feasible to maintain an object-free and smooth roadside clear zone as recommended in design guidelines. Currently, clear zone width and sideslope are used to determine roadside hazard ratings (RHRs) to quantify the roadside safety of rural two-lane roadways on a seven-point pictorial scale. Since these two variables are continuous and can be treated as random, probabilistic analysis can be applied as an alternative method to address existing uncertainties. Specifically, using reliability analysis, it is possible to quantify roadside safety levels by treating the clear zone width and sideslope as two continuous, rather than discrete, variables. The objective of this manuscript is to present a new approach for defining the reliability index for measuring roadside safety on rural two-lane roads. To evaluate the proposed approach, we gathered five years (2009-2013) of Illinois run-off-road (ROR) crash data and identified the roadside features (i.e., clear zone widths and sideslopes) of 4500 300ft roadway segments. Based on the obtained results, we confirm that reliability indices can serve as indicators to gauge safety levels, such that the greater the reliability index value, the lower the ROR crash rate.

  5. Development of safety performance functions for Spanish two-lane rural highways on flat terrain.

    Science.gov (United States)

    Garach, Laura; de Oña, Juan; López, Griselda; Baena, Leticia

    2016-10-01

    Over decades safety performance functions (SPF) have been developed as a tool for traffic safety in order to estimate the number of crashes in a specific road section. Despite the steady progression of methodological innovations in the crash analysis field, many fundamental issues have not been completely addressed. For instance: Is it better to use parsimonious or fully specified models? How should the goodness-of-fit of the models be assessed? Is it better to use a general model for the entire sample or specific models based on sample stratifications? This paper investigates the above issues by means of several SPFs developed using negative binomial regression models for two-lane rural highways in Spain. The models were based on crash data gathered over a 5-year period, using a broad number of explanatory variables related to exposure, geometry, design consistency and roadside features. Results show that the principle of parsimony could be too restrictive and that it provided simplistic models. Most previous studies apply conventional measurements (i.e., R(2), BIC, AIC, etc.) to assess the goodness-of-fit of models. Seldom do studies apply cumulative residual (CURE) analysis as a tool for model evaluation. This paper shows that CURE plots are essential tools for calibrating SPF, while also providing information for possible sample stratification. Previous authors suggest that sample segmentation increases the model accuracy. The results presented here confirm that finding, and show that the number of significant variables in the final models increases with sample stratification. This paper point out that fully models based on sample segmentation and on CURE may provide more useful insights about traffic crashes than general parsimonious models when developing SPF.

  6. When do drivers abort an overtaking maneuver 5 on two-lane rural roads

    NARCIS (Netherlands)

    Farah, H.

    2016-01-01

    Overtaking on two-lane roads is a complex driving maneuver. Drivers who desire to overtake a lead vehicle need to evaluate the available gaps in the opposite direction and accept a sufficient gap to successfully complete the overtaking maneuver. However, often drivers realize that the gap they acce

  7. Crash prediction model for two-lane rural highways in the Ashanti region of Ghana

    Directory of Open Access Journals (Sweden)

    Williams Ackaah

    2011-07-01

    Full Text Available Crash Prediction Models (CPMs have been used elsewhere as a useful tool by road Engineers and Planners. There is however no study on the prediction of road traffic crashes on rural highways in Ghana. The main objective of the study was to develop a prediction model for road traffic crashes occurring on the rural sections of the highways in the Ashanti Region of Ghana. The model was developed for all injury crashes occurring on selected rural highways in the Region over the three (3 year period 2005–2007. Data was collected from 76 rural highway sections and each section varied between 0.8 km and 6.7 km. Data collected for each section comprised injury crash data, traffic flow and speed data, and roadway characteristics and road geometry data. The Generalised Linear Model (GLM with Negative Binomial (NB error structure was used to estimate the model parameters. Two types of models, the ‘core’ model which included key exposure variables only and the ‘full’ model which included a wider range of variables were developed. The results show that traffic flow, highway segment length, junction density, terrain type and presence of a village settlement within road segments were found to be statistically significant explanatory variables (p<0.05 for crash involvement. Adding one junction to a 1 km section of road segment was found to increase injury crashes by 32.0% and sections which had a village settlement within them were found to increase injury crashes by 60.3% compared with segments with no settlements. The model explained 61.2% of the systematic variation in the data. Road and Traffic Engineers and Planners can apply the crash prediction model as a tool in safety improvement works and in the design of safer roads. It is recommended that to improve safety, highways should be designed to by-pass village settlements and that the number of junctions on a highway should be limited to carefully designed ones.

  8. Development of comprehensive accident models for two-lane rural highways using exposure, geometry, consistency and context variables.

    Science.gov (United States)

    Cafiso, Salvatore; Di Graziano, Alessandro; Di Silvestro, Giacomo; La Cava, Grazia; Persaud, Bhagwant

    2010-07-01

    In Europe, approximately 60% of road accident fatalities occur on two-lane rural roads. Thus, research to develop and enhance explanatory and predictive models for this road type continues to be of interest in mitigating these accidents. To this end, this paper describes a novel and extensive data collection and modeling effort to define accident models for two-lane road sections based on a unique combination of exposure, geometry, consistency and context variables directly related to the safety performance. The first part of the paper documents how these were identified for the segmentation of highways into homogeneous sections. Next, is a description of the extensive data collection effort that utilized differential cinematic GPS surveys to define the horizontal alignment variables, and road safety inspections (RSIs) to quantify the other road characteristics related to safety. The final part of the paper focuses on the calibration of models for estimating the expected number of accidents on homogeneous sections that can be characterized by constant values of the explanatory variables. Several candidate models were considered for calibration using the Generalized Linear Modeling (GLM) approach. After considering the statistical significance of the parameters related to exposure, geometry, consistency and context factors, and goodness of fit statistics, 19 models were ranked and three were selected as the recommended models. The first of the three is a base model, with length and traffic as the only predictor variables; since these variables are the only ones likely to be available network-wide, this base model can be used in an empirical Bayesian calculation to conduct network screening for ranking "sites with promise" of safety improvement. The other two models represent the best statistical fits with different combinations of significant variables related to exposure, geometry, consistency and context factors. These multiple variable models can be used, with

  9. Development of adjustment functions to assess combined safety effects of multiple treatments on rural two-lane roadways.

    Science.gov (United States)

    Park, Juneyoung; Abdel-Aty, Mohamed

    2015-02-01

    Numerous studies have attempted to evaluate the safety effectiveness of specific single treatment on roadways by estimating crash modification factors (CMFs). However, there is a need to also assess safety effects of multiple treatments since multiple treatments are usually simultaneously applied to roadways. Due to the lack of sufficient CMFs of multiple treatments, the Highway Safety Manual (HSM) provides combining method for multiple CMFs. However, it is cautioned in the HSM and related sources that combined safety effect of multiple CMFs may be over or under estimated. Moreover, the literature did not evaluate the accuracy of the combining method using CMFs obtained from the same study area. Thus, the main objectives of this research are: (1) to estimate CMFs and crash modification functions (CM Functions) for two single treatments (shoulder rumble strips, widening (1-9ft) shoulder width) and combination (installing shoulder rumble strips+widening shoulder width) using the observational before-after with empirical Bayes (EB) method and (2) to develop adjustment factors and functions to assess combined safety effects of multiple treatments based on the accuracy of the combined CMFs for multiple treatments estimated by the existing combining method. Data was collected for rural two-lane roadways in Florida and Florida-specific safety performance functions (SPFs) were estimated for different crash types and severities. The CM Functions and adjustment functions were developed using linear and nonlinear regression models. The results of before-after with EB method show that the two single treatments and combination are effective in reducing total and SVROR (single vehicle run-off roadway) crashes. The results indicate that the treatments were more safety effective for the roadway segments with narrower original shoulder width in the before period. It was found that although the CMFs for multiple treatments (i.e., combination of two single treatments) were generally

  10. Speed Distribution on Two-Lane Rural Highways with Mixed Traffic: A Case Study in North East India

    Science.gov (United States)

    Saha, Pritam; Roy, Nabanita; Sarkar, Ashoke Kumar; Pal, Manish

    2017-06-01

    This work focuses on minimising inaccuracies in distributional assumptions of speed data on two-lane roads with heterogeneous traffic to improve accuracy in capacity and level of service analysis. Accordingly, field study was conducted on a two-lane highway in India that exhibits heterogeneity in its traffic composition. Two distribution functions, namely, normal and logistic were examined for the observed speed data. The appropriate function was chosen using a methodology based on K-S test and field validation. Logistic distribution function was found to exhibit its aptness in describing speed under such traffic and was, thereby, considered in estimating the limiting speed of slower vehicles that tends to obstruct the flow of traffic. Vehicles that move at or below this speed cause delay to the faster ones resulting in formation of platoons at moderate and heavy flow when passing is restricted. Since the percent time-spent-following, a performance measure to assess level-of-service of two-lane highways, considers proportion of vehicles that are trapped inside platoons, it is imperative to estimate the limiting speed of slower vehicles correctly to approximate the delayed vehicles.

  11. Rural Communities Communicating: The Emergence of Two-Way Interactive Video in Southwestern, Rural, Small Schools.

    Science.gov (United States)

    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…

  12. Capacity of two-lane roads

    CSIR Research Space (South Africa)

    Kennedy, DA

    1991-01-01

    Full Text Available Relationships of speed vs density, volume and percentage loop occupation are investigated. The effect of differing directional splits in traffic volumes is also examined. A method of determining the Level-of Service of two-lane roads in terms...

  13. Continuum modeling for two-lane traffic flow

    Institute of Scientific and Technical Information of China (English)

    Haijun Huang; Tieqiao Tang; Ziyou Gao

    2006-01-01

    In this paper,we study the continuum modeling of traffic dynamics for two-lane freeways.A new dynamics model is proposed, which contains the speed gradient-based momentum equations derived from a car-following theory suited to two-lane traffic flow.The conditions for securing the linear stability of the new model are presented.Numerical tests are carried out and some nonequilibrium phenomena are observed, such as small disturbance instability,stop-andgo waves,local clusters and phase transition.

  14. Lane changing analysis for two-lane traffic flow

    Institute of Scientific and Technical Information of China (English)

    Tieqiao Tang; Haijun Huang; S.C.Wong; Rui Jiang

    2007-01-01

    In this paper,the two-lane traffic are studiedby using the lane-changing rules in the car-followingmodels.The simulation show that the frequent lanechanging occurs when the lateral distance in car fol-lowing activities is considered and it gives rise to oscil-lating waves.In contrast,if the lateral distance is notconsidered (or considered occasionally),the lane chang-ing appears infrequently and soliton waves occurs.Thisimplies that the stabilization mechanism no longer func-tions when the lane changing is permitted.Since theoscillating and soliton waves correspond to the unsta-ble and metastable flow regimes,respectively,our studyverifies that a phase transition may occur as a result ofthe lane changing.

  15. A modified two-lane traffic model considering drivers' personality

    Science.gov (United States)

    Zhu, H. B.; Zhang, N. X.; Wu, W. J.

    2015-06-01

    Based on the two-lane traffic model proposed by Chowdhury et al., a modified traffic model (R-STCA model, for short) is presented, in which the new symmetric lane changing rules are introduced by considering driving behavioral difference and dynamic headway. After the numerical simulation, a broad scattering of simulated points is exhibited in the moderate density region on the flow-density plane. The synchronized flow phase accompanied with the wide moving jam phase is reproduced. The spatial-temporal profiles indicate that the vehicles move according to the R-STCA model can change lane more easily and more realistically. Then vehicles are convenient to get rid of the slow vehicles that turn into plugs ahead, and hence the capacity increases. Furthermore the phenomenon of the high speed car-following is discovered by using the R-STCA model, which has been already observed in the traffic measured data. All these results indicate that the presented model is reasonable and more realistic.

  16. The effect of interruption probability in lattice model of two-lane traffic flow with passing

    Science.gov (United States)

    Peng, Guanghan

    2016-11-01

    A new lattice model is proposed by taking into account the interruption probability with passing for two-lane freeway. The effect of interruption probability with passing is investigated about the linear stability condition and the mKdV equation through linear stability analysis and nonlinear analysis, respectively. Furthermore, numerical simulation is carried out to study traffic phenomena resulted from the interruption probability with passing in two-lane system. The results show that the interruption probability with passing can improve the stability of traffic flow for low reaction coefficient while the interruption probability with passing can destroy the stability of traffic flow for high reaction coefficient on two-lane highway.

  17. Traffic states and jamming transitions induced by a bus in two-lane traffic flow

    Science.gov (United States)

    Nagai, Ryoichi; Nagatani, Takashi; Taniguchi, Naoki

    2005-05-01

    We study the traffic states and jamming transitions induced by a bus (slow car) in a two-lane traffic of cars. We use the dynamic model which is an extended one of the optimal velocity model to take into account the lane changing. The fundamental (flow-density) diagram is presented. The fundamental diagram changes highly by introducing a bus on a two-lane roadway. It is found that there are the six distinct states for the two-lane traffic flow including a bus. The spatio-temporal patterns are presented for the distinct traffic states. The dynamical state of traffic changes with density of cars. It is shown that the dynamical transitions among the distinct traffic states occur at some values of density. The phase diagram (region map) is shown for the two-lane traffic flow including a bus.

  18. A new traffic model with the consideration of coupling effect with two lanes

    Institute of Scientific and Technical Information of China (English)

    Peng Guang-Han; Sun Di-Hua; He Heng-Pan

    2009-01-01

    This paper introduces a new two-lane high-order continuum model by embedding the two delay time scales con-tinuum traffic model presented by Xue (2003 Phys. Rev. E 68 066123) into the multi-lane model proposed by Daganzo (1997 Transpn. Res. B 31 83) with the consideration of the coupling effect between the vehicles of two lanes in instan-taneous traffic situation and lane-change effect. In the novel model, the coupling effect of two lanes and phenomena of lane change, which were not discussed in Daganzo's model and Xue's model, are taken into account. Numerical simulation shows that it is in accordance with real traffic flow. This obviously indicates that the new phenomenon and behaviour are analogous results as single lane presented by Xue, and the proposed model is more reasonable on two lanes. Furthermore, the generation rate between two lanes is also investigated. The results show that the formation and diffusion of traffic shock wave can be better simulated on two lanes.

  19. Influence of lane change on stability analysis for two-lane traffic flow

    Institute of Scientific and Technical Information of China (English)

    Zheng Liang; Ma Shou-Feng; Zhong Shi-Quan

    2011-01-01

    This paper deals mainly with the influence of lane changing behaviours on the stability of two-lane traffic flow under a periodic boundary condition.Following the description of an optimal velocity model for two vehicle groups and the derivation of their stability conditions,the feedback signals,which involve information about vehicles from both lanes acting on the two-lane traffic system,are introduced into the optimal velocity model.The control signals play a role in alleviating the traffic jam only if the traffic state is in congestion,and their role will vanish if the traffic state is in the steady state.The numerical simulations show that lane changing behaviours can break the steady state of two-lane traffic flow and aggravate the traffic disturbance,but the control method would successfully suppress the traffic jam eventually,which implies that the conclusions obtained here have certain theoretical and practical significance.

  20. Feedback control for car following model based on two-lane traffic flow

    Science.gov (United States)

    Ge, Hong-xia; Meng, Xiang-pei; Zhu, Hui-bing; Li, Zhi-Peng

    2014-08-01

    In the paper, two-lane traffic flow considering lane changing behaviors has been discussed based on the control theory, and the friction interference which is from the neighbor lane has been taken into account. By using the control method, the stability condition is derived. The feedback signals, which include vehicular information from both lanes, acting on the two-lane traffic system have been introduced into the Full Velocity Difference car-following model. In the end, simulations are conducted to examine the validity and reasonability of the control method. It is proven that lane changing behaviors can aggravate the traffic perturbation. The traffic flow congestion could be suppressed by using the control method and the simulation results are in good agreement with the theoretical analysis.

  1. A Two-Lane Cellular Automata Model with Influence of Next-Nearest Neighbor Vehicle

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this paper, we propose a new two-lane cellular automata model in which the influence of the next-nearest neighbor vehicle is considered. The attributes of the traffic system composed of fast-lane and slow-lane are investigated by the new traffic model. The simulation results show that the proposed two-lane traffic model can reproduce some traffic phenomena observed in real traffic, and that maximum flux and critical density are close to the field measurements.Moreover, the initial density distribution of the fast-lane and slow-lane has much influence on the traffic flow states.With the ratio between the densities of slow lane and fast lane increasing the lane changing frequency increases, but maximum flux decreases. Finally, the influence of the sensitivity coefficients is discussed.

  2. Analysis of average density difference effect in a new two-lane lattice model

    Science.gov (United States)

    Zhang, Geng; Sun, Di-Hua; Zhao, Min; Liu, Wei-Ning; Cheng, Sen-Lin

    2015-11-01

    A new lattice model is proposed by taking the average density difference effect into account for two-lane traffic system according to Transportation Cyber-physical Systems. The influence of average density difference effect on the stability of traffic flow is investigated through linear stability theory and nonlinear reductive perturbation method. The linear analysis results reveal that the unstable region would be reduced by considering the average density difference effect. The nonlinear kink-antikink soliton solution derived from the mKdV equation is analyzed to describe the properties of traffic jamming transition near the critical point. Numerical simulations confirm the analytical results showing that traffic jam can be suppressed efficiently by considering the average density difference effect for two-lane traffic system.

  3. Flow difference effect in the two-lane lattice hydrodynamic model

    Institute of Scientific and Technical Information of China (English)

    Wang Tao; Gao Zi-You; Zhao Xiao-Mei; Tian Jun-Fang; Zhang Wen-Yi

    2012-01-01

    By introducing a flow difference effect,a modified lattice two-lane traffic flow model is proposed,which is proved to be capable of improving the stability of traffic flow.Both the linear stability condition and the kink-antikink solution derived from the modified Korteweg-de Vries (mKdV) equation are analyzed.Numerical simulations verify the theoretical analysis.Furthermore,the evolution laws under different disturbances in the metastable region are studied.

  4. Controlling traffic jams on a two-lane road using delayed-feedback signals

    Institute of Scientific and Technical Information of China (English)

    Liang ZHENG; Shi-quan ZHONG; Shou-feng MA

    2012-01-01

    This paper focuses mainly on the stability analysis of two-lane traffic flow with lateral friction,which may be caused by irregular driving behavior or poorly visible road markings,and also attempts to reveal the formation mechanism of traffic jams.Firstly,a two-lane optimal velocity (OV) model without control signals is proposed and its stability condition is obtained from the viewpoint of control theory.Then delayed-feedback control signals composed of distance headway information from both lanes are added to each vehicle and a vehicular control system is designed to suppress the traffic jams.Lane change behaviors are also incorporated into the two-lane OV model and the corresponding information about distance headway and feedback signals is revised.Finally,the results of numerical experiments are shown to verify that when the stability condition is not met,the position disturbances and resulting lane change behaviors do indeed deteriorate traffic performance and cause serious traffic jams.However,once the proper delayed-feedback control signals are implemented,the traffic jams can be suppressed efficiently.

  5. Two-lane traffic-flow model with an exact steady-state solution.

    Science.gov (United States)

    Kanai, Masahiro

    2010-12-01

    We propose a stochastic cellular-automaton model for two-lane traffic flow based on the misanthrope process in one dimension. The misanthrope process is a stochastic process allowing for an exact steady-state solution; hence, we have an exact flow-density diagram for two-lane traffic. In addition, we introduce two parameters that indicate, respectively, driver's driving-lane preference and passing-lane priority. Due to the additional parameters, the model shows a deviation of the density ratio for driving-lane use and a biased lane efficiency in flow. Then, a mean-field approach explicitly describes the asymmetric flow by the hop rates, the driving-lane preference, and the passing-lane priority. Meanwhile, the simulation results are in good agreement with an observational data, and we thus estimate these parameters. We conclude that the proposed model successfully produces two-lane traffic flow particularly with the driving-lane preference and the passing-lane priority.

  6. Overtaking Safety Evaluation and Setting of Auxiliary Lane on Two-Lane Highway in China

    Directory of Open Access Journals (Sweden)

    Guozhu Cheng

    2016-01-01

    Full Text Available Overtaking experiments on four two-lane highways were conducted. The data of overtaking conflict time (the time difference between the time of driving back to the original lane and the time of meeting with the first opposing vehicle and experimental drivers’ risk feeling were observed. Membership was adopted to denote the experimental drivers’ risk feelings which also denote the severity of traffic conflict. Membership ranges from 0 to 1 and corresponding risk becomes higher; that is, traffic conflict becomes more serious. According to the observed relationship between overtaking conflict time, and drivers’ risk feeling membership, Cauchy distribution function was adopted as membership function. The thresholds of the severity of traffic conflict were determined through Delphi method. The relationship model among traffic volume, overtaking conflict time and design speed was established according to experimental data. Then the idea of setting auxiliary lane on two-lane highway in China was presented. And the traffic volume values that need setting auxiliary lane corresponding to different design speed and traffic conflict degree were given according to the established model. It is expected to improve the traffic safety level of two-lane highway in China through setting auxiliary lane.

  7. Comparison of consistency assessment models for isolated horizontal curves in two-lane rural highways

    Directory of Open Access Journals (Sweden)

    Danilo Cárdenas-Aguilar

    2015-01-01

    Full Text Available El análisis de consistencia del diseño geométrico de carreteras tiene por objetivo contar con carreteras más seguras. Para analizar consistencia existen dos tipos de modelos: agregados y desagregados. Los primeros consideran diferencias de velocidades de diseño y operación en la mitad de la curva. Los segundos consideran la variación espacial del perfil de velocidad de operación. Este trabajo comparó los dos métodos usando datos empíricos de velocidad de operación obtenidos con un GPS de 10 Hz en 34 curvas horizontales simples de carreteras de dos carriles en Chile. Los resultados permitieron concluir que solo en 19 casos los métodos resultaron equivalentes entre sí. Esta compatibilidad sólo se da cuando el perfil de velocidad de operación posee poca varianza especial. Si el perfil de velocidad de operación es muy variable espacialmente, el nivel de consistencia obtenido usando los 2 métodos es diferente, caso en el cual resulta más conveniente combinarlos.

  8. Contribution to Accident Prediction Models Development for Rural Two-Lane Roads in Serbia

    Directory of Open Access Journals (Sweden)

    Draženko Glavić

    2016-08-01

    Full Text Available Over the last three decades numerous research efforts have been conducted worldwide to determine the relationship between traffic accidents and traffic and road characteristics. So far, the mentioned studies have not been carried out in Serbia and in the region. This paper represents one of the first attempts to develop accident prediction models in Serbia. The paper provides a comprehensive literature review, describes procedures for collection and analysis of the traffic accident data, as well as the methodology used to develop the accident prediction models. The paper presents models obtained by both univariate and multivariate regression analyses. The obtained results are compared to the results of other studies and comparisons are discussed. Finally, the paper presents conclusions and important points for future research. The results of this research can find theoretical as well as practical application.

  9. Shape-dependence of the barrier for skyrmions on a two-lane racetrack

    Science.gov (United States)

    Müller, Jan

    2016-10-01

    Single magnetic skyrmions are localized whirls in the magnetization with an integer winding number. They have been observed on nano-meter scales up to room temperature in multilayer structures. Due to their small size, topological winding number, and their ability to be manipulated by extremely tiny forces, they are often called interesting candidates for future memory devices. The two-lane racetrack has to exhibit two lanes that are separated by an energy barrier. The information is then encoded in the position of a skyrmion which is located in one of these close-by lanes. The artificial barrier between the lanes can be created by an additional nanostrip on top of the track. Here we study the dependence of the potential barrier on the shape of the additional nanostrip, calculating the potentials for a rectangular, triangular, and parabolic cross section, as well as interpolations between the first two. We find that a narrow barrier is always repulsive and that the height of the potential strongly depends on the shape of the nanostrip, whereas the shape of the potential is more universal. We finally show that the shape-dependence is redundant for possible applications.

  10. Two-lane traffic rules for cellular automata: A systematic approach

    Energy Technology Data Exchange (ETDEWEB)

    Nagel, K. [Los Alamos National Lab., NM (United States)]|[Forschungszentrum Juelich (Germany). Hoechsteleistungsrechenzentrum HLRZ; Wolf, D.E. [Forschungszentrum Juelich (Germany). Hoechstleistungsrechenzentrum HLRZ]|[Gerhard-Mercator-Univ., Duisburg (Germany). Theoretische Physik; Wagner, P. [Univ. zu Koeln (Germany). Zentrum Fuer Paralleles Rechnen]|[Deutsche Forschungsanstalt fuer Luft- und Raumfahrt, Koeln (Germany); Simon, P. [Los Alamos National Lab., NM (United States)

    1997-11-05

    Microscopic modeling of multi-lane traffic is usually done by applying heuristic lane changing rules, and often with unsatisfying results. Recently, a cellular automation model for two-lane traffic was able to overcome some of these problems and to produce a correct density inversion at densities somewhat below the maximum flow density. In this paper, the authors summarize different approaches to lane changing and their results, and propose a general scheme, according to which realistic lane changing rules can be developed. They test this scheme by applying it to several different lane changing rules, which, in spite of their differences, generate similar and realistic results. The authors thus conclude that, for producing realistic results, the logical structure of the lane changing rules, as proposed here, is at least as important as the microscopic details of the rules.

  11. Event-Based Modeling of Driver Yielding Behavior to Pedestrians at Two-Lane Roundabout Approaches.

    Science.gov (United States)

    Salamati, Katayoun; Schroeder, Bastian J; Geruschat, Duane R; Rouphail, Nagui M

    2014-01-01

    Unlike other types of controlled intersections, drivers do not always comply with the "yield to pedestrian" sign at the roundabouts. This paper aims to identify the contributing factors affecting the likelihood of driver yielding to pedestrians at two-lane roundabouts. It further models the likelihood of driver yielding based on these factors using logistic regression. The models have been applied to 1150 controlled pedestrian crossings at entry and exit legs of two-lane approaches of six roundabouts across the country. The logistic regression models developed support prior research that the likelihood of driver yielding at the entry leg of roundabouts is higher than at the exit. Drivers tend to yield to pedestrians carrying a white cane more often than to sighted pedestrians. Drivers traveling in the far lane, relative to pedestrian location, have a lower probability of yielding to a pedestrian. As the speed increases the probability of driver yielding decreases. At the exit leg of the roundabout, drivers turning right from the adjacent lane have a lower propensity of yielding than drivers coming from other directions. The findings of this paper further suggest that although there has been much debate on pedestrian right-of-way laws and distinction between pedestrian waiting positions (in the street versus at the curb), this factor does not have a significant impact on driver yielding rate. The logistic regression models also quantify the effect of each of these factors on propensity of driver yielding. The models include variables which are specific to each study location and explain the impact size of each study location on probability of yielding. The models generated in this research will be useful to transportation professionals and researchers interested in understanding the factors that impact driver yielding at modern roundabouts. The results of the research can be used to isolate factors that may increase yielding (such as lower roundabout approach speeds

  12. Perceiving and Acting on Complex Affordances: How Children and Adults Bicycle across Two Lanes of Opposing Traffic

    Science.gov (United States)

    Grechkin, Timofey Y.; Chihak, Benjamin J.; Cremer, James F.; Kearney, Joseph K.; Plumert, Jodie M.

    2013-01-01

    This investigation examined how children and adults negotiate a challenging perceptual-motor problem with significant real-world implications--bicycling across two lanes of opposing traffic. Twelve- and 14-year-olds and adults rode a bicycling simulator through an immersive virtual environment. Participants crossed intersections with continuous…

  13. Perceiving and Acting on Complex Affordances: How Children and Adults Bicycle across Two Lanes of Opposing Traffic

    Science.gov (United States)

    Grechkin, Timofey Y.; Chihak, Benjamin J.; Cremer, James F.; Kearney, Joseph K.; Plumert, Jodie M.

    2013-01-01

    This investigation examined how children and adults negotiate a challenging perceptual-motor problem with significant real-world implications--bicycling across two lanes of opposing traffic. Twelve- and 14-year-olds and adults rode a bicycling simulator through an immersive virtual environment. Participants crossed intersections with continuous…

  14. Two-lane traffic simulations with a blockage induced by an accident car

    Science.gov (United States)

    Zhu, H. B.; Lei, L.; Dai, S. Q.

    2009-07-01

    Based on the two-lane traffic model proposed by Chowdhury et al., a highway traffic model with a blockage induced by an accident car is proposed, in which both symmetric lane changing rules and asymmetric lane changing rules are adopted. The fundamental diagrams and spatial-temporal profiles are presented after the numerical simulation and the jam transition is studied. It is shown that the accident car not only causes a local jam behind the accident car, but also causes vehicles to cluster in the bypass lane. The asymmetric lane changing rules are more advantageous in reducing the local jam than the symmetric lane changing rules when the accident car is in the right lane, and the symmetric lane changing rules are superior when the accident car is in the left lane. Furthermore the curves of lane-changing frequency against the total density are given. It is found that the vehicles will change lane more frequently when traffic is inhomogeneous with different types of vehicle or with an accident car.

  15. Motion of Skyrmions in Well-Separated Two-Lane Racetracks

    Science.gov (United States)

    Lai, P.; Zhao, G. P.; Morvan, F. J.; Wu, S. Q.; Ran, N.

    Magnetic skyrmions are topological structures which can be used to store information as data bits in metallic racetrack memories. Their good properties, such as their stability, small size and low currents needed to drive them make them better candidates than traditional magnetic domain walls for the building of the next generation data storage. A skyrmion racetrack memory has been suggested, with the binary data encoded in the distance between skyrmions when the racetrack is a single lane. Here, we propose a new skyrmion-based two-lane racetrack structure separated by a high-K (high magnetocrystalline anisotropy) middle lane, which confines the skyrmions in their respective lanes. This design gives a new data presentation for the skyrmions on the racetrack. Phase diagrams for the skyrmion motion on the proposed racetrack as functions of the current density, middle lane anisotropy, middle lane width and DMI constant have been calculated and given, demonstrating that skyrmions can be driven in different lanes of the racetrack. This design offers the possibility of building an ultrafast and energy-efficient skyrmion transport device.

  16. Analysis of factors associated with traffic injury severity on rural roads in Iran

    Directory of Open Access Journals (Sweden)

    Andishe Ranjbari

    2012-01-01

    Full Text Available BACKGROUND: Iran is a country with one of the highest rates of traffic crash fatality and injury, and seventy percent of these fatalities happen on rural roads. The objective of this study is to identify the significant factors influencing injury severity among drivers involved in crashes on two kinds of major rural roads in Iran: two-lane, two-way roads and freeways. METHODS: According to the dataset, 213569 drivers were involved in rural road crashes in Iran, over the 3 years from 2006 to 2008. The Classification And Regression Tree method (CART was applied for 13 independent variables, and one target variable of injury severity with 3 classes of no-injury, injury and fatality. Some of the independent variables were cause of crash, collision type, weather conditions, road surface conditions, driver's age and gender and seat belt usage. The CART model was trained by 70% of these data, and tested with the rest. RESULTS: It was indicated that seat belt use is the most important safety factor for two-lane, two-way rural roads, but on freeways, the importance of this variable is less. Cause of crash, also turned out to be the next most important variable. The results showed that for two-lane, two-way rural roads, "improper overtaking" and "speeding", and for rural freeways, "inattention to traffic ahead", "vehicle defect", and "movement of pedestrians, livestock and unauthorized vehicles on freeways" are the most serious causes of increasing injury severity. CONCLUSIONS: The analysis results revealed seat belt use, cause of crash and collision type as the most important variables influencing the injury severity of traffic crashes. To deal with these problems, intensifying police enforcement by means of mobile patrol vehicles, constructing overtaking lanes where necessary, and prohibiting the crossing of pedestrians and livestock and the driving of unauthorized vehicles on freeways are necessary. Moreover, creating a rumble strip on the two edges of

  17. Analysis of factors associated with traffic injury severity on rural roads in Iran.

    Science.gov (United States)

    Kashani, Ali Tavakoli; Shariat-Mohaymany, Afshin; Ranjbari, Andishe

    2012-01-01

    Iran is a country with one of the highest rates of traffic crash fatality and injury, and seventy percent of these fatalities happen on rural roads. The objective of this study is to identify the significant factors influencing injury severity among drivers involved in crashes on two kinds of major rural roads in Iran: two-lane, two-way roads and freeways. According to the dataset, 213569 drivers were involved in rural road crashes in Iran, over the 3 years from 2006 to 2008. The Classification And Regression Tree method (CART) was applied for 13 independent variables, and one target variable of injury severity with 3 classes of no-injury, injury and fatality. Some of the independent variables were cause of crash, collision type, weather conditions, road surface conditions, driver's age and gender and seat belt usage. The CART model was trained by 70% of these data, and tested with the rest. It was indicated that seat belt use is the most important safety factor for two-lane, two-way rural roads, but on freeways, the importance of this variable is less. Cause of crash, also turned out to be the next most important variable. The results showed that for two-lane, two-way rural roads, "improper overtaking" and "speeding", and for rural freeways, "inattention to traffic ahead", "vehicle defect", and "movement of pedestrians, livestock and unauthorized vehicles on freeways" are the most serious causes of increasing injury severity. The analysis results revealed seat belt use, cause of crash and collision type as the most important variables influencing the injury severity of traffic crashes. To deal with these problems, intensifying police enforcement by means of mobile patrol vehicles, constructing overtaking lanes where necessary, and prohibiting the crossing of pedestrians and livestock and the driving of unauthorized vehicles on freeways are necessary. Moreover, creating a rumble strip on the two edges of roads, and paying attention to the design consistency of

  18. Two-Way communication with energy exchange

    DEFF Research Database (Denmark)

    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...

  19. Two-way quantum communication channels

    CERN Document Server

    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.

  20. Modeling mechanical restriction differences between car and heavy truck in two-lane cellular automata traffic flow model

    Science.gov (United States)

    Li, Xin; Li, Xingang; Xiao, Yao; Jia, Bin

    2016-06-01

    Real traffic is heterogeneous with car and truck. Due to mechanical restrictions, the car and the truck have different limited deceleration capabilities, which are important factors in safety driving. This paper extends the single lane safety driving (SD) model with limited deceleration capability to two-lane SD model, in which car-truck heterogeneous traffic is considered. A car has a larger limited deceleration capability while a heavy truck has a smaller limited deceleration capability as a result of loaded goods. Then the safety driving conditions are different as the types of the following and the leading vehicles vary. In order to eliminate the well-known plug in heterogeneous two-lane traffic, it is assumed that heavy truck has active deceleration behavior when the heavy truck perceives the forming plug. The lane-changing decisions are also determined by the safety driving conditions. The fundamental diagram, spatiotemporal diagram, and lane-changing frequency were investigated to show the effect of mechanical restriction on heterogeneous traffic flow. It was shown that there would be still three traffic phases in heterogeneous traffic condition; the active deceleration of the heavy truck could well eliminate the plug; the lane-changing frequency was low in synchronized flow; the flow and velocity would decrease as the proportion of heavy truck grows or the limited deceleration capability of heavy truck drops; and the flow could be improved with lane control measures.

  1. Translational Medicine: A two-way road

    Directory of Open Access Journals (Sweden)

    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.

  2. Two-way cable television system characterization

    Science.gov (United States)

    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.

  3. The Analysis of Two-Way Functional Data Using Two-Way Regularized Singular Value Decompositions

    KAUST Repository

    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.

  4. A two-lane cellular automaton traffic flow model with the influence of driver, vehicle and road

    Science.gov (United States)

    Zhao, Han-Tao; Nie, Cen; Li, Jing-Ru; Wei, Yu-Ao

    2016-07-01

    On the basis of one-lane comfortable driving model, this paper established a two-lane traffic cellular automata model, which improves the slow randomization effected by brake light. Considering the driver psychological characteristics and mixed traffic, we studied the lateral influence between vehicles on adjacent lanes. Through computer simulation, the space-time diagram and the fundamental figure under different conditions are obtained. The study found that aggressive driver makes a slight congestion in low-density traffic and improves the capacity of high-density traffic, when the density exceeds 20pcu/km the more aggressive drivers the greater the flow, when the density below 40pcu/km driver character makes an effect, the more cautious driver, the lower the flow. The ratio of big cars has the same effect as the ratio of aggressive drivers. Brake lights have the greatest impact on traffic flow and when the density exceeds 10pcu/km the traffic flow fluctuates. Under periodic boundary conditions, the disturbance of road length on traffic is minimal. The lateral influence only play a limited role in the medium-density conditions, and only affect the average speed of traffic at low density.

  5. Analysis of a novel two-lane lattice model on a gradient road with the consideration of relative current

    Science.gov (United States)

    Cao, Jin-Liang; Shi, Zhong-Ke

    2016-04-01

    In this paper, a novel hydrodynamic lattice model is proposed by considering of relative current for two-lane gradient road system. The stability condition is obtained by using linear stability theory and shown that the stability of traffic flow varies with three parameters, that is, the slope, the sensitivity of response to the relative current and the rate of lane changing. The stable region increases with the increasing of one of them when another two parameters are constant. By using nonlinear analysis, the Burgers, Korteweg-de Vries, and modified Korteweg-de Vries equations are derived to describe the phase transition of traffic flow. Their solutions present the density wave as the triangular shock wave, soliton wave, and kink-antikink wave in the stable, metastable, and unstable region, respectively, which can explain the phase transitions from free traffic to stop-and-go traffic, and finally to congested traffic. To verify the theoretical results, a series of numerical simulations are carried out. The numerical results are consistent with the analytical results. To check the novel model, calibration are taken based on the empirical traffic flow data. The theoretical results and numerical results show that the traffic flow on the gradient road becomes more stable and the traffic congestion can be efficiently suppressed by considering the relative current and lane changing, and the empirical analysis shows that the novel lattice model is reasonable.

  6. A viscous continuum traffic flow model with consideration of the coupling effect for two-lane freeways

    Institute of Scientific and Technical Information of China (English)

    Sun Di-Hua; Peng Guang-Han

    2009-01-01

    In this paper,the viscous continuum traffic flow model for a single lane is extended to the traffic flow for two-lane freeways. The proposed model is a higher-order continuum model considering the coupling and lane changing effects of the vehicles on two adjacent lanes. It results from integrating the Taylor series expansion of the viscous continuum traffic flow model proposed by Ge (2006 Physics A 371 667) into the multi-lane model presented by Daganzo (1997Transpn. Res. B 31 83). Our proposed model may be used to describe non-anisotropic behaviour because of lane changing in multi-lane traffic. A linear stability analysis is given and the neutral stability condition is obtained. Also,issues related to lane changing,shock waves and rarefaction waves,local clustering and phase transition are investigated through a simulation experiment. The simulation results show that the proposed model is capable of explaining some particular traffic phenomena commonly observable in real world traffic flow.

  7. 考虑交通障碍的双车道扩展交通流模型%Extend Two-lane Traffic Flow Model with a Blockage

    Institute of Scientific and Technical Information of China (English)

    李建锋; 赵靖

    2012-01-01

    借助智能交通系统(ITS),把扩展的车辆跟驰模型应用于双车道,建立根据确定规则进行换道的扩展交通流跟驰模型.通过改变发车车头间距,在开放边界条件下左车道有交通事故发生时,重现实际交通中的交通流现象.数值模拟发现:双车道交通流模型能够有效地抑制交通流阻塞,提高交通流量.%The extended car-following model is applied into two-lane system based on intelligent transportation system application (ITS). Then, an extended model of two-lane traffic in which vehicles change the lane by a deterministic rule is presented. The typical traffic induced by a car accident on the left lane under the open boundary is investigated. The simulation results suggest that the two-lane traffic model can suppress the traffic jam and enhance the traffic flow effectively.

  8. Achievable Rates for Two-Way Wire-Tap Channels

    CERN Document Server

    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.

  9.  HOMEinTOUCH Designing two-way Ambient Communication

    DEFF Research Database (Denmark)

    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...

  10. Virtual Classrooms: Educational Opportunity through Two-Way Interactive Television.

    Science.gov (United States)

    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…

  11. Lung Disease, Indigestion, and Two-Way Tables

    Science.gov (United States)

    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…

  12. Two-Way Regularized Fuzzy Clustering of Multiple Correspondence Analysis.

    Science.gov (United States)

    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.

  13. Transfer as a two-way process: testing a model

    NARCIS (Netherlands)

    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

  14. Bilingual Two-Way Immersion Programs Benefit Academic Achievement

    Science.gov (United States)

    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…

  15. Creating Two-Way Dual Language Schools through Effective Leadership.

    Science.gov (United States)

    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)

  16. Experimental Study of Drivers' Overtaking Behavior on Two-lane Highways%双车道公路驾驶员超车行为试验研究

    Institute of Scientific and Technical Information of China (English)

    刘江

    2013-01-01

    By high-accuracy GPS dynamic data acquisition instrument,the author designed the experimental plan of drivers' overtaking on the two-lane highways with the drivers' perceive to measure the overtakable gap and the returnable gap.The experimental results could be used as the basis for the study of two-lane highways' capacity,drivers' overtaking behavior,the design of overtaking sight distance and intelligent transportation system.%通过利用高精度全球定位系统(global positioning system,GPS)动态数据采集仪,结合驾驶员超车过程的感受度,设计了双车道公路上测量可回车车头时距和可超车车头时距的试验方案,获得的实验数据可为研究双车道公路通行能力、驾驶员超车行为、设计超车视距以及构建智能交通系统提供实测数据依据.

  17. Study on traffic states and jamming transitions for two-lane highway including a bus by using a model with calibrated optimal velocity function

    Science.gov (United States)

    Li, Zhipeng; Yi, Yi

    2014-07-01

    In this paper, traffic states and jamming transitions on two-lane highway including a bus are studied by using a car following model with a calibrated optimal velocity function. We derive a new flow-density diagram with four distinctly separated traffic states, which is different from that of the earlier study obtained by applying the OVM with theoretical optimal velocity function. The spatio-temporal diagrams are presented to illustrate phase characteristics of each traffic state. It is found that the phase characteristic features of two of four states are different from any state of the earlier result, and traffic flow of state 2 and state 3 can reproduce some characteristics observed from empirical investigations such as centralized lane-changing, hanging tail of cluster, and synchronized flow. In addition, we have clarified the lane-changing behaviors and their effects on two-lane traffic flow including a bus. It is shown that the velocity oscillations behind the bus can help the lane-changing in state 2 and the behaviors of lane-changing are the important reason of forming of the synchronized flow in state 3. It is also concluded that lane-changing can only improve the current in the region of middle density.

  18. Study on the effects of driver's lane-changing aggressiveness on traffic stability from an extended two-lane lattice model

    Science.gov (United States)

    Li, Zhipeng; Zhang, Run; Xu, Shangzhi; Qian, Yeqing

    2015-07-01

    In this paper, the effects of driver's lane-changing aggressiveness on the stability of traffic flow of two-lane are studied by using a generalized lattice hydrodynamic model with consideration of lane-changing aggressiveness of each individual. The effect of lane-changing aggressiveness parameter on traffic stability is derived through employing linear stability analysis with finding that the driver's lane-changing aggressiveness has an important impact on the stability of the traffic flow in a two-lane system. To describe the phase transition, the mKdV equation near the critical point is derived by using the reductive perturbation method, with obtaining the dependence of the propagation kink solution for traffic jams on the lane-changing aggressiveness. It can be concluded from the phase diagram of stability criterion that the higher lane-changing aggressiveness leads to a more stable traffic flow. In addition, the stabilizing effect of the optimal current difference weakens gradually with the increasing of the lane-changing aggressiveness adjusting coefficient, even vanishes when the value of lane-changing aggressiveness adjusting coefficient is greater than a critical value. Theoretical conclusions are also confirmed by the numerical simulations.

  19. Methods for obtaining two way memory effect and stressed two way memory effect of CuAlNi single crystals

    Institute of Scientific and Technical Information of China (English)

    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.

  20. A two-way regularization method for MEG source reconstruction

    KAUST Repository

    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.

  1. TWO-WAY ROAD NETWORK DESIGN PROBLEM WITH VARIABLE LANES

    Institute of Scientific and Technical Information of China (English)

    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.

  2. Two way time transfer results at NRL and USNO

    Science.gov (United States)

    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.

  3. Two way time transfer results at NRL and USNO

    Science.gov (United States)

    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.

  4. Flexural Behavior of Two-Way Sandwiched Slabs

    OpenAIRE

    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...

  5. Two-Way Immersion 101: Designing and Implementing a Two-Way Immersion Education Program at the Elementary Level

    OpenAIRE

    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...

  6. Improve the teaching quality by two-way education mode

    Directory of Open Access Journals (Sweden)

    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.

  7. Lexical need as a two-way reality cognition tool

    Directory of Open Access Journals (Sweden)

    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.

  8. Two-way radios and scanners for dummies

    CERN Document Server

    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

  9. Decoy States and Two Way Quantum Key Distribution Schemes

    CERN Document Server

    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.

  10. Database Security Two Way Authentication Using Graphical Password

    Directory of Open Access Journals (Sweden)

    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

  11. The Two Way Wiretap Channel: Theory and Practice

    CERN Document Server

    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...

  12. Distributed Space Time Coding for Wireless Two-way Relaying

    CERN Document Server

    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 ...

  13. Two-way frequency trasfer on a multiplexed fiber network

    CERN Document Server

    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.

  14. Quantum error correction assisted by two-way noisy communication.

    Science.gov (United States)

    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

  15. Overlay cognitive radio systems with adaptive two-way relaying

    KAUST Repository

    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.

  16. Personality and having children: a two-way relationship.

    Science.gov (United States)

    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.

  17. 双车道公路设置附加车道交通量条件研究%Traffic Volume Conditions of Setting Auxiliary Lane on Two-lane Highway

    Institute of Scientific and Technical Information of China (English)

    程国柱; 翟露露; 秦丽辉; 王玉霞

    2015-01-01

    In order to reduce traffic accidents and improve operating efficiency on two-lane highway, the concept of setting auxiliary lane on two-lane highway is proposed, and the traffic volume conditions of setting up auxiliary lane on two-lane highway are studied. Data is obtained through vehicle experiment on two-lane highway, and the relational model among the traffic conflict time, the traffic volume and the design speed on two-lane highway is established. Based on the established model, the different conditions of traffic volume of setting auxiliary lane on two-lane highway are obtained. It shows that auxiliary lane should be set when traffic volume is more than 495 veh/h/ln and 454 veh/h/ln respectively on two-lane highway with the design speed of 80 km/h and 60km/h. It isn't recommend to set auxiliary lane on two-lane highway with the design speed of 40 km/h because the benefit is not obvious.%为了减少双车道公路交通事故数量、提高运行效率,提出了双车道公路设置附加车道的理念,基于试验数据开展了双车道公路设置附加车道的交通量条件研究.通过双车道公路实车实验获得的基础数据,建立了双车道公路交通冲突时间与交通量、设计速度的关系模型.依据构建的模型,给出了对应不同设计速度的双车道公路设置附加车道的交通量条件.基于样本数据的研究结果表明:设计速度为80 km/h的双车道公路,单向交通量大于495 veh/h/ln时,应设置附加车道;设计速度为60 km/h的双车道公路,单向交通量大于454 veh/h/ln,应设置附加车道;设计速度为40 km/h及以下的双车道公路,设置附加车道效益不明显,不建议设置.

  18. Studying the effect of spiral curves and intersection angle, on the accident ratios in two-lane rural highways in Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Hossain Jalal Kamali

    2013-07-01

    Full Text Available Safety in highways is one of the most important subjects in Transportation Engineering. Increasing rate of vehicles and the needs to design or geometrically modifying the highways, emphasized on the safe-designing of the roadways more than before. Between the constructive components of the highway, horizontal curves due to the more occurrences of accidents are of great importance. The American ministry of highway and transportation introduced the software IHSDM, with variant capabilities, to predict accidents. In this research, five types of curves (simple circle curve and clothoid-circle-clothoid at different intersection angles were designed, and accident rates based on the standard specifications on each curve was predicted by using the IHSDM, and the results are compared with each other. Finally, by processing the curves of accident rates versus the curves types and intersection angle, and comparing them with each other, the necessity of using spiral curves in the highway design is emphasized.

  19. Two-Way Communication Using RFID Equipment and Techniques

    Science.gov (United States)

    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

  20. Periodontitis and diabetes: a two-way relationship.

    Science.gov (United States)

    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.

  1. Two-Way Coupling Vortex Method and Its Application

    Institute of Scientific and Technical Information of China (English)

    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.

  2. Diabetes and hepatitis C : A two-way association

    Directory of Open Access Journals (Sweden)

    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.

  3. Coupled Two-Way Clustering Analysis of Gene Microarray Data

    CERN Document Server

    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.

  4. Two-way conversations between cold atoms and semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Periodontitis and type II diabetes: a two-way relationship.

    Science.gov (United States)

    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.

  6. Coupled two-way clustering analysis of gene microarray data

    Science.gov (United States)

    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.

  7. 78 FR 31576 - Enforcement Proceeding; Certain Two-Way Global Satellite Communication Devices, System and...

    Science.gov (United States)

    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...

  8. Two-way Shape Memory Effect of NiTi under Compressive Loading Cycles

    Science.gov (United States)

    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.

  9. Robustness of two-way quantum communication protocols against Trojan horse attack

    CERN Document Server

    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.

  10. A comparison of one-way video and two-way video educational videoteleconferencing

    Science.gov (United States)

    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)?

  11. 33 CFR 167.173 - Off Delaware Bay: Two-Way Traffic Route.

    Science.gov (United States)

    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...

  12. An Experimental Two-Way Video Teletraining System: Design, Development and Evaluation.

    Science.gov (United States)

    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)…

  13. 77 FR 58579 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof...

    Science.gov (United States)

    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...

  14. An Experimental Two-Way Video Teletraining System: Design, Development and Evaluation.

    Science.gov (United States)

    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)…

  15. Two-Way Text Messaging: An Interactive Mobile Learning Environment in Higher Education

    Science.gov (United States)

    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…

  16. Research on Relationship of Traffic Condition and Traffic Safety of Two-Lane Highway in Plane Areas%平原区双车道公路交通条件与交通安全的关系研究

    Institute of Scientific and Technical Information of China (English)

    李强; 王蓉蓉; 路维; 胡江碧

    2012-01-01

    On the bais of traffic accident data of the two-lane highway in plane areas, the influence of vertical-section, cross-section and intersection with the traffic accidents, and contrasting the analysis with conclusion abroad are discussed , then a conclusion on the relationship of the traffic condition and the traffic safety of two-lane highway in plane areas is got, a traffic safety prediction model is established,so it has important significance on the upgrading the highway safety.%以平原区双车道公路交通事故资料为基础,分析了道路平曲线和纵断面线形及交叉口等因素与交通事故的关系,将分析结论和国外研究结果相对比,得出我国平原区双车道公路交通条件与交通安全的关系,并建立交通安全性预测模型,对提升我国双车道公路安全性具有重要的意义.

  17. The two-way feedback and passing-way of human body

    Institute of Scientific and Technical Information of China (English)

    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.

  18. A model of two-way selection system for human behavior.

    Directory of Open Access Journals (Sweden)

    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.

  19. The Asymptotic Standard Errors of Some Estimates of Uncertainty in the Two-Way Contingency Table

    Science.gov (United States)

    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)

  20. RUSSIAN-ENGLISH INTERACTIONS AS A TWO-WAY CHANNEL OF LINGUISTIC EXCHANGE

    Directory of Open Access Journals (Sweden)

    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.

  1. Improvement of two-way continuous-variable quantum key distribution with virtual photon subtraction

    Science.gov (United States)

    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.

  2. Physical Layer Security for Two-Way Untrusted Relaying with Friendly Jammers

    OpenAIRE

    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...

  3. Hash-and-Forward Relaying for Two-Way Relay Channel

    CERN Document Server

    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.

  4. Relativity on a two-way moving sidewalk. Relativite sur un tapis roulant

    Energy Technology Data Exchange (ETDEWEB)

    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).

  5. Perspektif Karyawan Perbankan pada Komunikasi Internal dengan Two-Way Symmetrical Communication dan Internal Marketing

    Directory of Open Access Journals (Sweden)

    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.

  6. The Promise and Potential of Two-Way Immersion in Catholic Schools

    Science.gov (United States)

    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…

  7. Response of stiff piles to random two-way lateral loading

    DEFF Research Database (Denmark)

    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...

  8. Discussing Difference: Color-Blind Collectivism and Dynamic Dissonance in Two-Way Immersion Contexts

    Science.gov (United States)

    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…

  9. A Mandarin/English Two-Way Immersion Program: Language Proficiency and Academic Achievement

    Science.gov (United States)

    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…

  10. Two-way immersion – a teaching/learning method for bi-/plurilingual communities?

    Directory of Open Access Journals (Sweden)

    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. 

  11. GENERALIZED CONFIDENCE REGIONS OF FIXED EFFECTS IN THE TWO-WAY ANOVA

    Institute of Scientific and Technical Information of China (English)

    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.

  12. Two-Way Tables: Issues at the Heart of Statistics and Probability for Students and Teachers

    Science.gov (United States)

    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…

  13. Towards Understanding the Two Way Interaction Effects of Extraversion and Openness to Experience on Career Commitment

    Science.gov (United States)

    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…

  14. A Minicomputer Software System for Administering Interactive Instructional Programs via Two-Way Cable Television.

    Science.gov (United States)

    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)

  15. Two-way causation in life satisfaction research : Structural equation models with granger causation

    NARCIS (Netherlands)

    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,

  16. Languages across Borders: Social Network Development in an Adolescent Two-Way Dual-Language Program

    Science.gov (United States)

    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.…

  17. Analysis of Two Way Simply Supported Slabs With Central Sunk Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    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.

  18. Cross-Layer Optimization of Two-Way Relaying for Statistical QoS Guarantees

    CERN Document Server

    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...

  19. More Powerful Tests of Simple Interaction Contrasts in the Two-Way Factorial Design

    Science.gov (United States)

    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…

  20. A Mandarin/English Two-Way Immersion Program: Language Proficiency and Academic Achievement

    Science.gov (United States)

    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…

  1. Fluid–particle flow simulations using two-way-coupled mesoscale SPH–DEM and validation

    NARCIS (Netherlands)

    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

  2. Mechanical Verification of a Two-Way Sliding Window Protocol (Full version including proofs)

    NARCIS (Netherlands)

    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.

  3. Combating Inequalities in Two-Way Language Immersion Programs: Toward Critical Consciousness in Bilingual Education Spaces

    Science.gov (United States)

    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…

  4. Improving Bilingual Service Delivery in Catholic Schools through Two-Way Immersion

    Science.gov (United States)

    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…

  5. Two-Way Bilingual Immersion Programs: Toward a More Inclusive Agenda in Bilingual Education.

    Science.gov (United States)

    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…

  6. Advanced two-way satellite frequency transfer by carrier-phase and carrier-frequency measurements

    Science.gov (United States)

    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.

  7. Two-Way Bilingual Education: Students Learning through Two Languages. Final Report.

    Science.gov (United States)

    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…

  8. Language Choice & Language Power: Children's Use of Korean & English in a Two-Way Immersion Program

    Science.gov (United States)

    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…

  9. General immunity and superadditivity of two-way Gaussian quantum cryptography

    Science.gov (United States)

    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.

  10. General immunity and superadditivity of two-way Gaussian quantum cryptography.

    Science.gov (United States)

    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.

  11. Coupled Two-Way Clustering Analysis of Breast Cancer and Colon Cancer Gene Expression Data

    CERN Document Server

    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.

  12. An experimental study of the two-way shape memory effect in a NiTi tubular actuator

    Science.gov (United States)

    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.

  13. Two-way nesting in split-explicit ocean models: Algorithms, implementation and validation

    Science.gov (United States)

    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.

  14. Improved two-way six-state protocol for quantum key distribution

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. Thermally Activated Composite with Two-Way and Multi-Shape Memory Effects

    Directory of Open Access Journals (Sweden)

    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.

  16. The electrical power shortage problem solved by two-way communication; Toveis kan loese effektproblem

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Two-way nesting in split-explicit ocean models : algorithms, implementation and validation

    OpenAIRE

    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...

  18. Two-Way Gene Interaction From Microarray Data Based on Correlation Methods

    OpenAIRE

    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...

  19. Relay Selection and Resource Allocation in One-Way and Two-Way Cognitive Relay Networks

    KAUST Repository

    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.

  20. Student and Teacher Oral Language Use in a Two-Way Spanish/English Immersion School

    Science.gov (United States)

    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…

  1. Fluid-particle flow and validation using two-way-coupled mesoscale SPH-DEM

    OpenAIRE

    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...

  2. An investigation of two-way text messaging use with deaf students at the secondary level.

    Science.gov (United States)

    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.

  3. The application of laser two-way depletion model in AVLIS for uranium

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. A Rhetorical Grammar Analysis of Two Ways of Seeing a River

    Institute of Scientific and Technical Information of China (English)

    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.

  5. Two-way regularization for MEG source reconstruction via multilevel coordinate descent

    KAUST Repository

    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.

  6. Damage Assessment of Two-Way Bending RC Slabs Subjected to Blast Loadings

    Directory of Open Access Journals (Sweden)

    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.

  7. Accurate calculation of Stokes drag for point-particle tracking in two-way coupled flows

    CERN Document Server

    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...

  8. Two-way text messaging: an interactive mobile learning environment in higher education

    Directory of Open Access Journals (Sweden)

    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.

  9. Multiantenna relay beamforming design for QoS discrimination in two-way relay networks.

    Science.gov (United States)

    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.

  10. Damage Assessment of Two-Way Bending RC Slabs Subjected to Blast Loadings

    Science.gov (United States)

    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

  11. WRF-CMAQ two-way coupled system with aerosol feedback: software development and preliminary results

    Directory of Open Access Journals (Sweden)

    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

  12. TWO-LANE BLACKTOP: REFUGEES & TORTURE

    Directory of Open Access Journals (Sweden)

    JESÚS GARCÍA CÍVICO

    2017-06-01

    Full Text Available The right not to be subjected to torture or to cruel, inhuman or degrading treatment or punishment, and the right of asylum have, individually considered, an extensive field of application", but it is possible to point out some traits in common. Firsty, in both rights undelie the moral spirit of the Universal Declaration of Human Rights. At the same time, according to the recent reports of the main human rights organisations, both rights are in deep political crisis. Furthermore, is possible to see that sometimes they cross each other: there is a triple «zone of intersection between the right of asylum and the right not to suffer torture, inhuman or degrading treatment: one of the reasons for escaping from a country is to avoid suffering torture ("refuge after torture" secondly, sometimes inhuman and degrading treatment occur precisely in the process of seeking asylum ("inhuman treatment in the refuge", finally, there are countries with strong deficiencies in their immigration policies and this can produce a perverse effect: the transfer of potential asylum seekers to countries where they are at risk of torture or inhuman treatment again ("torture or inhuman and degrading treatment after asylum".

  13. An Inequality Concerning Quantitative Duality in an Asymmetry Two-Way Interferometer

    Institute of Scientific and Technical Information of China (English)

    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).

  14. Performance analysis for a two-way relaying power line network with analog network coding

    Institute of Scientific and Technical Information of China (English)

    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.

  15. Parametric down-conversion with local operation and two-way classical communication

    Institute of Scientific and Technical Information of China (English)

    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.

  16. On the performance of spectrum sharing systems with two-way relaying and multiuser diversity

    KAUST Repository

    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.

  17. Relay selection and resource allocation for two-way DF-AF cognitive radio networks

    KAUST Repository

    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.

  18. Outage performance of two-way DF relaying systems with a new relay selection metric

    KAUST Repository

    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.

  19. Resource Allocation with Subcarrier Pairing in OFDMA Two-Way Relay Networks

    CERN Document Server

    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.

  20. Distributed Role Selection With ANC and TDBC Protocols in Two-Way Relaying Systems

    KAUST Repository

    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.

  1. A score test for the agronomical overlap effect in a two-way classification model

    Directory of Open Access Journals (Sweden)

    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.

  2. Multiple phase screen calculation of two-way spherical wave propagation in the ionosphere

    Science.gov (United States)

    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.

  3. Two-Way Optical Frequency Comparisons Over 100km Telecommunication Network Fibers

    CERN Document Server

    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.

  4. Prospective Teachers’ Semiotic Conflicts in Computing Probabilities from a Two-Way Table

    Directory of Open Access Journals (Sweden)

    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.

  5. Bandwidth and power allocation for two-way relaying in overlay cognitive radio systems

    KAUST Repository

    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.

  6. Two-Way Bending Properties of Shape Memory Composite with SMA and SMP

    Directory of Open Access Journals (Sweden)

    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.

  7. Joint Network Coding and Opportunistic Transmission for Two-Way Relay Fading Channels

    CERN Document Server

    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...

  8. Two-way Fluid-Structure Interaction Simulation of a Micro Horizontal Axis Wind Turbine

    Directory of Open Access Journals (Sweden)

    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.

  9. Distributed cognitive two-way relay beamformer designs under perfect and imperfect CSI

    KAUST Repository

    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.

  10. Effect of width and boundary conditions on meeting maneuvers on two-way separated cycle tracks.

    Science.gov (United States)

    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.

  11. Two-Way Training Design for Discriminatory Channel Estimation in Wireless MIMO Systems

    CERN Document Server

    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...

  12. Superimposed XOR: Approaching Capacity Bounds of the Two-Way Relay Channels

    CERN Document Server

    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...

  13. Turbulent phase noise on asymmetric two-way ground-satellite coherent optical links

    Science.gov (United States)

    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.

  14. Advanced transportation system study: Manned launch vehicle concepts for two way transportation system payloads to LEO

    Science.gov (United States)

    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

  15. Two-way cooperative AF relaying in spectrum-sharing systems: Enhancing cell-edge performance

    KAUST Repository

    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.

  16. PL/SQL and Bind Variable: the two ways to increase the efficiency of Network Databases

    Directory of Open Access Journals (Sweden)

    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.

  17. A genetic algorithm for multiple relay selection in two-way relaying cognitive radio networks

    KAUST Repository

    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.

  18. Energy efficient design for MIMO two-way AF multiple relay networks

    KAUST Repository

    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.

  19. Double criticality and the two-way Boussinesq equation in stratified shallow water hydrodynamics

    Science.gov (United States)

    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.

  20. Precoder Design and Power Allocation for MIMO Cognitive Radio Two-Way Relaying Systems

    KAUST Repository

    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.

  1. Generalized F test and generalized deviance test in two-way ANOVA models for randomized trials.

    Science.gov (United States)

    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.

  2. Outage Probability and Power Allocation for Two-Way DF Relay Networks with Relay Selection

    Directory of Open Access Journals (Sweden)

    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.

  3. Beamforming in Two-Way Fixed Gain Amplify-and-Forward Relay Systems with CCI

    CERN Document Server

    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.

  4. Digital transceiver design for two-way AF-MIMO relay systems with imperfect CSI

    Science.gov (United States)

    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.

  5. A low complexity algorithm for multiple relay selection in two-way relaying Cognitive Radio networks

    KAUST Repository

    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.

  6. Performance analysis of two-way amplify and forward relaying with adaptive modulation

    KAUST Repository

    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.

  7. Symmetry breaking in optimal timing of traffic signals on an idealized two-way street

    Science.gov (United States)

    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.

  8. A two-way nesting procedure for an ocean model with application to the Norwegian Sea

    Energy Technology Data Exchange (ETDEWEB)

    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)

  9. A practical two-way system of quantum key distribution with untrusted source

    Institute of Scientific and Technical Information of China (English)

    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.

  10. Symmetry breaking in optimal timing of traffic signals on an idealized two-way street

    CERN Document Server

    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...

  11. On Achievable Rate Regions of the Asymmetric AWGN Two-Way Relay Channel

    CERN Document Server

    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.

  12. Energy Efficiency and Goodput Analysis in Two-Way Wireless Relay Networks

    CERN Document Server

    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.

  13. Alternative Awaiting and Broadcast for Two-Way Relay Fading Channels

    CERN Document Server

    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.

  14. Randomization for Security in Half-Duplex Two-Way Gaussian Channels

    CERN Document Server

    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).

  15. Optimal relay selection and power allocation for cognitive two-way relaying networks

    KAUST Repository

    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.

  16. VIDEO-BASED VEHICLE DETECTION ON A TWO-WAY ROAD

    Directory of Open Access Journals (Sweden)

    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.

  17. Development of a Portable Two-Way Communication and Information Device for Deafblind People.

    Science.gov (United States)

    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.

  18. Two-Way Selection for Growth Rate in the Common Carp (CYPRINUS CARPIO L.)

    Science.gov (United States)

    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

  19. On achievable rate of two-way relaying cognitive radio with space alignment

    KAUST Repository

    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.

  20. Two-way CSI-assisted AF relaying with HPA nonlinearity

    KAUST Repository

    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.

  1. Frequency transfer via a two-way optical phase comparison on a multiplexed fiber network.

    Science.gov (United States)

    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.

  2. Outage Performance of Decode-and-Forward in Two-Way Relaying with Outdated CSI

    KAUST Repository

    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.

  3. Mechanical properties of two-way different configurations of prestressed concrete members subjected to axial loading

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. A Nonparametric Test of Interaction in the General Two-Way Layout

    Directory of Open Access Journals (Sweden)

    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.

  5. Two-way coupled fluid structure interaction simulation of a propeller turbine

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Achieving Superior Two-Way Actuation by the Stress-Coupling of Nanoribbons and Nanocrystalline Shape Memory Alloy

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. 78 FR 21629 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof Issuance of...

    Science.gov (United States)

    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...

  8. 77 FR 51045 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof; Notice of...

    Science.gov (United States)

    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...

  9. Latino Children Attending a Two-Way Immersion Program in the United States: A Comparative Case Analysis

    Science.gov (United States)

    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…

  10. The Impact of Two-Way Dual-Immersion Programs on Initially English-Dominant Latino Students' Attitudes

    Science.gov (United States)

    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…

  11. Achieving Superior Two-Way Actuation by the Stress-Coupling of Nanoribbons and Nanocrystalline Shape Memory Alloy.

    Science.gov (United States)

    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.

  12. Celestial-mechanical interpretation of the two-way radio measurements of radial velocity of spacecraft for scientific applications

    Science.gov (United States)

    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.

  13. Mutual research capacity strengthening: a qualitative study of two-way partnerships in public health research

    Directory of Open Access Journals (Sweden)

    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

  14. 公交车停靠诱发交通瓶颈的元胞自动机模拟%Investigation on traffic bottleneck induce by bus stopping with a two-lane cellular automaton model

    Institute of Scientific and Technical Information of China (English)

    李庆定; 董力耘; 戴世强

    2009-01-01

    利用双车道元胞自动机模型,研究公交车停靠对道路混合交通流的影响.针对港湾式和非港湾式两种不同公交车站设置,在开放边界下模拟了公交车停靠所产生的交通瓶颈问题,给出了车辆入流概率.公交车比例相平面上的相图,区分了自由流相和拥挤相,研究了相图各区中公交车站附近的平均密度和速度分布图,比较了两种公交车站情况下的道路交通流的动力学特征.研究发现,当公交车比例较小时,与非港湾式车站相比,港湾式车站可以显著改善车站处的交通状况.%In this paper, the influence of typical bus stops on traffic flow is investigated with the cellular automaton traffic model. For on-line and off-line bus stops, a two-lane cellular automaton model is proposed to simulate the traffic bottleneck induced by bus stopping under the open boundary condition. The phase diagram in the phase plane of injection probability and bus fraction is provided and two phases, i.e., the free flow phase and congested flow phase, are distinguished. The distributions of the mean density and velocity near the bus stop in different traffic phases are given and the comparison of dynamical characteristics of traffic flows is made for different types of bus stops. It is found that using the off-line bus stop can significandy improve the traffic flow in its neighboring region, compared with the on-line bus stop in the case of small fraction of buses.

  15. Cross-Layer Design for Two-Way Relaying Networks with Multiple Antennas

    Directory of Open Access Journals (Sweden)

    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.

  16. A Novel Secure Transmission Scheme in MIMO Two-Way Relay Channels with Physical Layer Approach

    Directory of Open Access Journals (Sweden)

    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.

  17. Cognitive two-way relay beamforming: Design with resilience to channel state uncertainties

    KAUST Repository

    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.

  18. Fluid-particle flow modelling and validation using two-way-coupled mesoscale SPH-DEM

    CERN Document Server

    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...

  19. Optimization of a two-way MIMO amplify-and-forward relay network

    Science.gov (United States)

    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.

  20. Multi-pair cognitive two-way relaying and power allocation under imperfect CSI

    KAUST Repository

    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.

  1. Two-way self-consistent coupling of HEIDI in SWMF

    Science.gov (United States)

    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.

  2. EEG/MEG Source Reconstruction with Spatial-Temporal Two-Way Regularized Regression

    KAUST Repository

    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.

  3. Joint Source and Relay Precoding Designs for MIMO Two-Way Relaying Based on MSE Criterion

    CERN Document Server

    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...

  4. Pairwise Check Decoding for LDPC Coded Two-Way Relay Block Fading Channels

    CERN Document Server

    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...

  5. Source-receiver two-way wave extrapolation for prestack exploding-reflector modelling and migration

    KAUST Repository

    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.

  6. Two-way shape memory behavior of semi-crystalline elastomer under stress-free condition

    Science.gov (United States)

    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.

  7. Gaussian Two-way Relay Channel with Private Information for the Relay

    CERN Document Server

    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.

  8. Performance Analysis of Adaptive Physical Layer Network Coding for Wireless Two-way Relaying

    CERN Document Server

    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...

  9. Carrier-phase Two-Way Satellite Frequency Transfer over a Very Long Baseline

    CERN Document Server

    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...

  10. Artificial muscles made of chiral two-way shape memory polymer fibers

    Science.gov (United States)

    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.

  11. Usefulness of phage typing and "two-way ribotyping" to differentiate Salmonella enteritidis strains.

    Science.gov (United States)

    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.

  12. Robust distributed two-way relay beamforming in cognitive radio networks

    KAUST Repository

    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.

  13. Effective Two-way Communication of Environmental Hazards: Understanding Public Perception in the UK

    Science.gov (United States)

    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

  14. Two-way WKB Approximation Applied to GPR - COST Action TU1208

    Science.gov (United States)

    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

  15. Hippocampus and two-way active avoidance conditioning: Contrasting effects of cytotoxic lesion and temporary inactivation.

    Science.gov (United States)

    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

  16. Two-Way Radio Modem Data Transfer for Newborn Hearing Screening Devices.

    Science.gov (United States)

    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.

  17. Joint Preprocesser-Based Detectors for One-Way and Two-Way Cooperative Communication Networks

    KAUST Repository

    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.

  18. Examining Interior Grid Nudging Techniques Using Two-Way Nesting in the WRF Model for Regional Climate Modeling

    Science.gov (United States)

    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...

  19. SOME ASPECTS OF THE TWO WAY SHAPE MEMORY EFFECT INDUCED BY PSEUDOELASTIC CYCLING IN Cu-Zn-Al ALLOYS

    OpenAIRE

    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...

  20. Two Way Coupling RAM-SCB to the Space Weather Modeling Framework

    Science.gov (United States)

    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

  1. A Research on Errors in Two-way Satellite Time and Frequency Transfer

    Science.gov (United States)

    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

  2. High-Efficiency Ka-Band Waveguide Two-Way Asymmetric Power Combiner

    Science.gov (United States)

    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

  3. Comparison of one-way and two-way coupled analyses of electromagnetic machines considering magnetic and structural interactions

    Science.gov (United States)

    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.

  4. Research on Length of Blocked Road Section for Maintenance of Two-lane Highway in Mountain Area Based on Vissim%基于Vissim的山区双车道公路养护作业封闭段长度研究

    Institute of Scientific and Technical Information of China (English)

    孙文亮; 刘振清; 贺玉龙; 高发亮

    2012-01-01

    建立山区双车道公路养护作业区Vissim仿真模型,通过信号灯控制通行时间,模拟在不同封闭段长度下车辆的运行状态,对行程延误、排队长度、停车次数和停驶车辆百分比等参数进行分析,得出山区双车道公路单车道封闭,短期养护作业封闭段长度不宜大于200 m,长期养护作业封闭段长度不宜大于2500 m,这为山区双车道公路养护作业区设置和交通组织提供理论依据.%The simulation model of maintenance area for two-lane highway in mountain area was established based on Vissim. The model can simulate vehicles' running state with different lengths of blocked road section through signal lamp controlling time, and can analyze parameters such as trip delay, queuing length, number of stops and the percentage of suspended vehicles. The result shows that the blocked single-lane section length for short-term maintenance of two-lane highway in mountain area should be less than 200 m and that for long-term maintenance should be less than 2500 m. It provided a theoretical basis of setting maintenance area and transportation organizations for two-lane highway in mountain area.

  5. Cellular Multi-User Two-Way MIMO AF Relaying via Signal Space Alignment: Minimum Weighted SINR Maximization

    CERN Document Server

    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.

  6. Two-way shape memory effect and its stability in Ti-Ni-Hf high temperature shape memory alloy

    Institute of Scientific and Technical Information of China (English)

    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.

  7. Stress-Induced Martensitic Transformation Cycling and Two-Way Shape Memory Training in Cu-Zn-Al Alloys

    Science.gov (United States)

    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.

  8. Three-dimensional numerical simulation of a vertical axis tidal turbine using the two-way fluid structure interaction approach

    Institute of Scientific and Technical Information of China (English)

    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).

  9. The association in a two-way contingency table through log odds ratio analysis: the case of Sarno river pollution.

    Science.gov (United States)

    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.

  10. Meaning Making and Translanguaging in a Two-Way Dual-Language Program on the U.S.-Mexico Border

    Science.gov (United States)

    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…

  11. A Latent Class Multidimensional Scaling Model for Two-Way One-Mode Continuous Rating Dissimilarity Data

    Science.gov (United States)

    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…

  12. 21 CFR Appendix E to Subpart A of... - Elements To Be Considered in Developing a Two-Way Alert System

    Science.gov (United States)

    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...

  13. Teaching Practices and Language Use in Two-Way Dual Language Immersion Programs in a Large Public School District

    Science.gov (United States)

    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…

  14. Implementing Two-Way Dual-Language Immersion Programs: Classroom Insights from an Urban District. Research Brief. RB-9921

    Science.gov (United States)

    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…

  15. Teaching Practices and Language Use in Two-Way Dual Language Immersion Programs in a Large Public School District

    Science.gov (United States)

    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…

  16. Head-on crashes on two-way interurban roads: a public health concern in road safety

    Directory of Open Access Journals (Sweden)

    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

  17. Moments Based Framework for Performance Analysis of One-Way/Two-Way CSI-Assisted AF Relaying

    KAUST Repository

    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.

  18. 47 CFR 22.709 - Rural radiotelephone service application requirements.

    Science.gov (United States)

    2010-10-01

    ... CARRIER SERVICES PUBLIC MOBILE SERVICES Rural Radiotelephone Service § 22.709 Rural radiotelephone service... current and future demand for paging, two-way mobile and rural radiotelephone services (see § 22.719(c... channel pairs must include a statement explaining why BETRS technology is not being proposed. (f)...

  19. Near-optimal power allocation with PSO algorithm for MIMO cognitive networks using multiple AF two-way relays

    KAUST Repository

    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.

  20. Impact of I/Q imbalance on the performance of two-way CSI-assisted AF relaying

    KAUST Repository

    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.

  1. Quantum hacking of two-way continuous-variable quantum key distribution using Trojan-horse attack

    Science.gov (United States)

    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).

  2. Tests of additivity in mixed and fixed effect two-way ANOVA models with single sub-class numbers

    OpenAIRE

    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....

  3. Two- way Shape Memory Effect in a Ti-Ni-Nb Shape Memory Alloy with Wide Hysteresis

    Institute of Scientific and Technical Information of China (English)

    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.

  4. Forensic application of gas chromatography-differential mobility spectrometry with two-way classification of ignitable liquids from fire debris.

    Science.gov (United States)

    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.

  5. Impact of turbulence on high-precision ground-satellite frequency transfer with two-way coherent optical links

    Science.gov (United States)

    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.

  6. Two-Way Street

    Institute of Scientific and Technical Information of China (English)

    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.

  7. "Two-Way Street"

    Science.gov (United States)

    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)

  8. Two-way development.

    Science.gov (United States)

    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.

  9. Two Ways to Lead

    Science.gov (United States)

    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…

  10. Two Ways to Lead

    Science.gov (United States)

    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…

  11. 中国双向投资问题研究%The Study on China's Two-way Investment

    Institute of Scientific and Technical Information of China (English)

    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.

  12. The influence of an atmospheric Two-Way coupled model system on the predictability of extratropical cyclones

    Science.gov (United States)

    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

  13. Two-way against one-way nesting for climate downscaling in Europe and the Mediterranean region using LMDZ4

    Science.gov (United States)

    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

  14. A Novel Approach Utilizing pnetCDF applying to the WRF-CMAQ two-way coupled model

    Science.gov (United States)

    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.

  15. Comparing One-way and Two-way Coupled Hydrometeorological Forecasting Systems for Flood Forecasting in the Mediterranean Region

    Science.gov (United States)

    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.

  16. Comparing One-Way and Two-Way Coupled Hydrometeorological Forecasting Systems for Flood Forecasting in the Mediterranean Region

    Directory of Open Access Journals (Sweden)

    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

  17. From implementation to learning: the importance of a two-way dialogue between practice and science in healthcare

    Directory of Open Access Journals (Sweden)

    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.

  18. Performance analysis of amplify-and-forward two-way relaying with co-channel interference and channel estimation error

    KAUST Repository

    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.

  19. Error tolerance of two-basis quantum key-distribution protocols using qudits and two-way classical communication

    CERN Document Server

    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.

  20. An R function for imputation of missing cells in two-way data sets by EM-AMMI algorithm

    Directory of Open Access Journals (Sweden)

    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

  1. Joint Bandwidth and Power Allocation for MIMO Two-Way Relays-Assisted Overlay Cognitive Radio Systems

    KAUST Repository

    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.

  2. Simulation and Analysis of Autonomous Time Synchronization Based on Asynchronism Two-way Inter-satellite Link

    Science.gov (United States)

    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.

  3. Role of B19' martensite deformation in stabilizing two-way shape memory behavior in NiTi

    Science.gov (United States)

    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.

  4. EFFECTS OF THE NUMBER OF RELAY ANTENNAS AND RELAY-POWER ON MIMO PRECODED TWO-WAY RELAYING

    Directory of Open Access Journals (Sweden)

    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.

  5. Joint terminals and relay optimization for two-way power line information exchange systems with QoS constraints

    Science.gov (United States)

    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.

  6. Impact of turbulent phase noise on frequency transfer with asymmetric two-way ground-satellite coherent optical links

    Science.gov (United States)

    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.

  7. Design and implementation of a two-way real-time communication system for audio over CATV networks

    Science.gov (United States)

    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.

  8. Applications of two-way satellite time and frequency transfer in the BeiDou navigation satellite system

    Science.gov (United States)

    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.

  9. Symmetric extension of bipartite quantum states and its use in quantum key distribution with two-way postprocessing

    Energy Technology Data Exchange (ETDEWEB)

    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

  10. On the performance of two-way multiuser mixed RF/FSO relay networks with opportunistic scheduling & asymmetric channel gains

    KAUST Repository

    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.

  11. Performance analysis of two-way amplify and forward relaying with adaptive modulation over multiple relay network

    KAUST Repository

    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.

  12. Relay-and-antenna selection and digital transceiver design for two-way AF-MIMO multiple-relay systems

    Science.gov (United States)

    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.

  13. Accessibility to information and communications technology for the social participation of youths with disabilities: a two-way street.

    Science.gov (United States)

    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.

  14. Feasibility of two-way polarization encoded quantum communication in an optical fiber populated with telecom traffic

    CERN Document Server

    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.

  15. Modeling particle-laden turbulent flows with two-way coupling using a high-order kernel density function method

    Science.gov (United States)

    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.

  16. Approach of the Two-way Influence Between Lean and Green Manufacturing and its Connection to Related Organisational Areas

    Directory of Open Access Journals (Sweden)

    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.

  17. Optimal transmit power allocation for MIMO two-way cognitive relay networks with multiple relays using AF strategy

    KAUST Repository

    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.

  18. Outage performance of opportunistic two-way amplify-and-forward relaying with outdated channel state information

    KAUST Repository

    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.

  19. A Comparison of One-Way and Two-Way Coupling Methods for Numerical Analysis of Fluid-Structure Interactions

    Directory of Open Access Journals (Sweden)

    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.

  20. Comparison of hydro-environmental impacts for ebb-only and two-way generation for a Severn Barrage

    Science.gov (United States)

    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.

  1. Time variable gravity retrieval and treatment of temporal aliasing using optical two-way links between GALILEO and LEO satellites

    Science.gov (United States)

    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.

  2. Two-way Transformation Scheme of EPON+EoC%EPON+EoC双向改造方案

    Institute of Scientific and Technical Information of China (English)

    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.

  3. Two-way shift of wavelength in holographic sensing of organic vapor in nanozeolites dispersed acrylamide photopolymer.

    Science.gov (United States)

    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.

  4. Two-way shape memory effect and alternating current driving characteristics of a TiNi alloy spring

    Institute of Scientific and Technical Information of China (English)

    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.

  5. Two Ways to Examine Differential Constitutive Equations: Initiated on Steady or Initiated on Unsteady (LAOS Shear Characteristics

    Directory of Open Access Journals (Sweden)

    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.

  6. Experimental and numerical analysis of pre-compressed masonry walls in two-way-bending with second order effects

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Eigen-Direction Alignment Based Physical-Layer Network Coding for MIMO Two-Way Relay Channels

    CERN Document Server

    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 ...

  8. Performance Analysis of Amplify-and-Forward Two-Way Relaying with Co-Channel Interference and Channel Estimation Error

    KAUST Repository

    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.

  9. Two-way self-consistent simulation of the inner magnetosphere driven by realistic electric and magnetic fields

    Science.gov (United States)

    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.

  10. Impacts of Pedestrians on Capacity and Delay of Major Street Through Traffic at Two-Way Stop-Controlled Intersections

    Directory of Open Access Journals (Sweden)

    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.

  11. A two-way enriched clinical trial design: combining advantages of placebo lead-in and randomized withdrawal.

    Science.gov (United States)

    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.

  12. Simulating low frequency sound transmission through walls and windows by a two-way coupled fluid structure interaction model

    Science.gov (United States)

    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.

  13. Two-way optical frequency comparisons at 5 ×10-21 relative stability over 100-km telecommunication network fibers

    Science.gov (United States)

    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.

  14. Digital Communication and Politics in Aragon. A two-way communication formula for the interaction between politicians and citizens

    Directory of Open Access Journals (Sweden)

    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.

  15. Guest-Induced Two-Way Structural Transformation in a Layered Metal-Organic Framework Thin Film.

    Science.gov (United States)

    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.

  16. Establishing a community of practice for Occupational Therapy curriculum development: the value of a two-way process.

    Science.gov (United States)

    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.

  17. Architecture vision and technologies for post-NPOESS weather prediction system: two-way interactive observing and modeling

    Science.gov (United States)

    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.

  18. Proper name anomia with preserved lexical and semantic knowledge after left anterior temporal lesion: a two-way convergence defect.

    Science.gov (United States)

    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).

  19. Oral Xeloda plus bi-platinu two-way combined chemotherapy in treatment of advanced gastrointestinal malignancies

    Institute of Scientific and Technical Information of China (English)

    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

  20. Improvement of orbit determination accuracy for Beidou Navigation Satellite System with Two-way Satellite Time Frequency Transfer

    Science.gov (United States)

    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.

  1. A hybrid surface layer parameterization scheme for the two-way fully coupled atmosphere-ocean wave system WEW

    Science.gov (United States)

    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

  2. Numerical simulation of the optimal two-mode attacks for two-way continuous-variable quantum cryptography in reverse reconciliation

    Science.gov (United States)

    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.

  3. Interaction driver-bicyclist on rural roads: Effects of cross-sections and road geometric elements.

    Science.gov (United States)

    Bella, Francesco; Silvestri, Manuel

    2017-03-17

    The interaction of motorists and bicyclists, particularly during passing maneuvers, is cited as one of the primary causes of bicyclist fatalities. This paper reports the results of a driving simulator study, which sought to analyze the effects that three cross-section configurations of a two-lane rural road and four geometric elements of the road have on driver behavior, during the interaction with a cyclist. A two-lane rural road, about 11km long, was designed and implemented in an advanced-interactive driving simulator. Three different cross-sections (all with same width, but with and without a bicycle lane and for different widths of bicycle lane) were tested. Forty participants carried out three driving sessions (one for each road alignment with different cross-section) and were exposed to the condition of bicycle traffic along four geometric elements of the alignment (2 tangents with different lengths, right curve and left curve). The driving simulator experiments were designed in such a way that, along the sections where the driver-cyclist interactions occurred, the oncoming traffic was absent. Overall, 468 speed profiles and 468 lateral position profiles were plotted to obtain the descriptive variables of the driver behavior during the interaction with the cyclist. The influences of cross-sections, geometric elements and bicycle traffic conditions on driver behavior were evaluated by a multivariate variance analysis. The presence of the cyclist determined different levels of influence on driver's trajectory for the three cross-sections. A wider bicycle lane ensured a higher later clearance distance between driver and cyclist, allowing safer overtaking maneuver. The interferences of the cyclist on driver's behavior depended on the geometric elements. On tangents, the lowest lateral clearances were recorded and no speed reduction was observed, compared to the cyclist absence condition. On the left curve, the higher lateral clearance was recorded, due to the

  4. Studies on Punching Shear Resistance of Two Way Slab Specimens with Partial Replacement of Cement by GGBS with Different Edge Conditions

    Science.gov (United States)

    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.

  5. Effect of Thermal Cycling under Load on Martensite Transformation and Two-way Shape Memory Effect in a TiNi Alloy

    Institute of Scientific and Technical Information of China (English)

    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.

  6. Effect of Training on Two-way Shape Memory Effect and Its Stability in a Ti-Ni-Hf High Temperature Shape Memory Alloy

    Institute of Scientific and Technical Information of China (English)

    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.

  7. "You Give Me Idea!": Collaborative Strides toward Bilingualism, Biliteracy, and Cross-Cultural Understanding in a Two-Way Partial Immersion Program

    Science.gov (United States)

    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…

  8. The Development, Pilot-Testing, and Dissemination of a Comprehensive Evaluation Model for Assessing the Effectiveness of a Two-Way Interactive Distance Learning System. Final Report.

    Science.gov (United States)

    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…

  9. The Development of Writing Skills in an Italian-English Two-Way Immersion Program: Evidence from First through Fifth Grade

    Science.gov (United States)

    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…

  10. Toward regional-scale modeling using the two-way nested global model TM5: Characterization of transport using SF6

    NARCIS (Netherlands)

    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

  11. Student Satisfaction, Self-Efficacy, and the Perception of the Two-Way Audio/Video Distance Learning Environment: A Preliminary Examination.

    Science.gov (United States)

    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…

  12. Middle-Class English Speakers in a Two-Way Immersion Bilingual Classroom: "Everybody Should Be Listening to Jonathan Right Now..."

    Science.gov (United States)

    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.…

  13. Exploring Associations among Writing Self-Perceptions, Writing Abilities, and Native Language of English-Spanish Two-Way Immersion Students

    Science.gov (United States)

    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…

  14. Exploring Associations among Writing Self-Perceptions, Writing Abilities, and Native Language of English-Spanish Two-Way Immersion Students

    Science.gov (United States)

    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…

  15. Differences in Achievement between Students Enrolled in a Transitional, Early Exit Bilingual Program and in a Dual Language: Two-Way Immersion Bilingual Program--A Pilot Study

    Science.gov (United States)

    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…

  16. Toward an Expanded Understanding of Two-Way Bilingual Immersion Education: Constructing Identity through a Critical, Additive Bilingual/Bicultural Pedagogy

    Science.gov (United States)

    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…

  17. A Latent Variable Approach to Listening and Reading: Testing Factorial Invariance Across Two Groups of Children in the Korean/English Two-Way Immersion Program.

    Science.gov (United States)

    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…

  18. The Development of Writing Skills in an Italian-English Two-Way Immersion Program: Evidence from First through Fifth Grade

    Science.gov (United States)

    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…

  19. Influence of Hydrogen and Number of Particle Variants on Ordinary and Two-Way Shape Memory Effects in Ti-Ni Single Crystals

    Science.gov (United States)

    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.

  20. Rural Aging

    Science.gov (United States)

    ... Rural Health Topics & States Topics View more Rural Aging The nation's population is aging, and with that change comes increased healthcare needs. ... Disease Control and Prevention report, The State of Aging and Health in America 2013 , the population 65 ...

  1. Two-way fiber-wireless convergence systems based on two-stage injection-locked VCSELs transmitter and optical interleaver.

    Science.gov (United States)

    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.

  2. Improvement of Two-Way Active Avoidance Memory Requires Protein Kinase A Activation and Brain-Derived Neurotrophic Factor Expression in the Dorsal Hippocampus

    OpenAIRE

    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 ...

  3. Impact of two-way air flow due to temperature difference on preventing the entry of outdoor particles using indoor positive pressure control method.

    Science.gov (United States)

    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.

  4. Fluid–structure coupling analysis of deformation and stress in impeller of an axial-flow pump with two-way passage

    Directory of Open Access Journals (Sweden)

    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.

  5. Two-Way Tether Gun

    Science.gov (United States)

    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.

  6. Two ways to support reflexivity

    DEFF Research Database (Denmark)

    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...

  7. Tropospheric carbon monoxide over the Pacific during HIPPO: two-way coupled simulation of GEOS-Chem and its multiple nested models

    Directory of Open Access Journals (Sweden)

    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

  8. Automated pipeline for classifying Aroclors in soil by gas chromatography/mass spectrometry using modulo compressed two-way data objects.

    Science.gov (United States)

    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.

  9. 数字电视接入网双向改造方案%Two-way Reform Scheme of Digital TV Access Network

    Institute of Scientific and Technical Information of China (English)

    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.

  10. Rural Supremacy

    OpenAIRE

    Shah, Meera

    2011-01-01

    The success of any brand depends on it acceptance by the consumers. This project highlights the rural buying behaviour. The rural consumers tend to show a closed mind towards branded goods and services. Though the current scenario is improved than the past but still large amount of rural market is untapped. The marketers now understand the potential at the bottom of the pyramid but there are doubts regarding the way this market can be reached and converted into customers. Many factors like in...

  11. Rural Supremacy

    OpenAIRE

    Shah, Meera

    2011-01-01

    The success of any brand depends on it acceptance by the consumers. This project highlights the rural buying behaviour. The rural consumers tend to show a closed mind towards branded goods and services. Though the current scenario is improved than the past but still large amount of rural market is untapped. The marketers now understand the potential at the bottom of the pyramid but there are doubts regarding the way this market can be reached and converted into customers. Many factors like in...

  12. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  13. Low overhead two-way time synchronization algorithm%一种低开销的双向时间同步算法

    Institute of Scientific and Technical Information of China (English)

    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.

  14. Two-way Comparative Pattern Matching Algorithm Suitable for Chinese%适合中文的双向比较模式匹配算法

    Institute of Scientific and Technical Information of China (English)

    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.

  15. One-Way Multishape-Memory Effect and Tunable Two-Way Shape Memory Effect of Ionomer Poly(ethylene-co-methacrylic acid).

    Science.gov (United States)

    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.

  16. Sum-Rate Maximization in Two-Way AF MIMO Relaying: Polynomial Time Solutions to a Class of DC Programming Problems

    CERN Document Server

    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...

  17. Rural Households

    DEFF Research Database (Denmark)

    2013-01-01

    dependency on state institutions under the Vietnamese transition to a market society. It discusses present poverty definitions and measures by comparing survey data with the formal economic categorization of rural households. Both the overall characteristics of rural society and qualitative data indicate...

  18. Going Rural

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Foreign banks are beginning to invest in China's rural financial system, helping to meet a strong need for capital As Chinese commercial banks retreat from the rural market, foreign banks appear ready to jump into a sector with a strong thirst for capital. In July, Rabobank Group, the International Finance Corp. and the United

  19. Rural Agrobusiness.

    Science.gov (United States)

    Treillon, Roland; And Others

    1992-01-01

    This publication describes the formation and evolution of rural agribusiness (RA) in the southern hemisphere as a precondition for improving the lives of families in rural communities, and focuses on RA endeavors created by development projects in Latin America, the Caribbean, and Africa. After a short introduction, the first section of this study…

  20. Haemodynamics of giant cerebral aneurysm: A comparison between the rigid-wall, one-way and two-way FSI models

    Science.gov (United States)

    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.

  1. Exploring ecology through science terms: A computer-supported vocabulary supplement to the science curriculum in a two-way immersion program

    Science.gov (United States)

    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.

  2. Characteristics of the martensitic transformation and the induced two-way shape memory effect after training by compressive pseudoelastic cycling in Cu-Zn-Al single crystals

    Science.gov (United States)

    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.

  3. Characteristics of the martensitic transformation and the induced two-way shape memory effect after training by compressive pseudoelastic cycling in Cu-Zn-Al single crystals

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. 文学与人类学的双向视野和认同%The Two-way Vision and Identity of Literature and Anthropology

    Institute of Scientific and Technical Information of China (English)

    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.

  5. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  6. The Albany Two-Way Radio Conferences, 1955-1981: a retrospective look at a program providing interactive continuing medical education at a distance.

    Science.gov (United States)

    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.

  7. Two-Way Interpretation about Climate Change: Preliminary Results from a Study in Select Units of the United States National Park System

    Science.gov (United States)

    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.

  8. Performance Analysis of Power Saving Class of Type I for Voice Service in Two-Way Communication in IEEE 802.16e

    Science.gov (United States)

    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.

  9. Tailored One-Way and Two-Way Shape Memory Capabilities of Poly(ɛ-Caprolactone)-Based Systems for Biomedical Applications

    Science.gov (United States)

    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

  10. Association between prepulse inhibition of the startle response and latent inhibition of two-way avoidance acquisition: A study with heterogeneous NIH-HS rats.

    Science.gov (United States)

    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.

  11. Rural Priority

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    As the Chinese economy soars ahead in the wake of the international financial crisis, more attention is being given to the country’s indus-trial, financial, investment and trade figures. But the Central Rural Work

  12. Rural nurses

    DEFF Research Database (Denmark)

    Wilson, Rhonda L.; Usher, Kim

    2015-01-01

    with descriptive techniques. In-depth interviews were conducted and the transcribed data were analysed using thematic techniques. Results: The results of this study demonstrate that in general rural people are willing to seek mental health care, and that rural nurses are well suited to provide initial care...... to young people. Conclusions: Non-traditional venues such as community, school and justice settings are ideal places where more convenient first conversations about mental health with young people and their families, and rural nurses should be deployed to these settings. Relevance to Clinical Practice......: Rural nurses are able to contribute important initial engagement interventions that enhance the early mental health care for young people when it is needed....

  13. 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

    Institute of Scientific and Technical Information of China (English)

    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

  14. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  15. The Comparison of Two Ways for Digital Channelization%两种数字信道化实现方法比较

    Institute of Scientific and Technical Information of China (English)

    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。

  16. A comparative study on the effects of the benzodiazepine midazolam and the dopamine agents, apomorphine and sulpiride, on rat behavior in the two-way avoidance test.

    Science.gov (United States)

    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.

  17. [Comparison of several expressions of two-way ANOVA for a latent factor: analysis of the relation between music and mood].

    Science.gov (United States)

    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.

  18. Investigation of Bending Trainings, Transformation Temperatures, and Stability of Two-Way Shape Memory Effect in NiTi-Based Ribbons

    Science.gov (United States)

    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.

  19. Genetic Mapping of Laminaria japonica and L. longissima Using Amplified Fragment Length Polymorphism Markers in a "Two-Way Pseudo-Testcross" Strategy

    Institute of Scientific and Technical Information of China (English)

    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.

  20. Numerical simulation of two-way coupling mechanism in particle-laden turbulent flow based on one-dimensional turbulence model

    Science.gov (United States)

    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.

  1. Experimental Study on Sandwich Bridge Decks with GFRP Face Sheets and a Foam-Web Core Loaded under Two-Way Bending

    Directory of Open Access Journals (Sweden)

    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.

  2. Influence of the mechanical loading history on the stress assisted two way memory effect in a Ti-Ni-Cu alloy

    Directory of Open Access Journals (Sweden)

    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.

  3. Improvement of two-way active avoidance memory requires protein kinase a activation and brain-derived neurotrophic factor expression in the dorsal hippocampus.

    Science.gov (United States)

    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.

  4. What Is Rural?

    Science.gov (United States)

    ... of mind. For others, rural is an objective quantitative measure. The USDA , Economic Research Service, provides insight to rural definitions with an article, Defining the "Rural" in Rural America: The use ...

  5. Signaled two-way avoidance learning using electrical stimulation of the inferior colliculus as negative reinforcement: effects of visual and auditory cues as warning stimuli

    Directory of Open Access Journals (Sweden)

    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

  6. Designing of the Two-way Suction Drainage Tube in Vacuum Sealing%封闭负压双向引流管的设计

    Institute of Scientific and Technical Information of China (English)

    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.

  7. The effect of Coriolis-Stokes forcing on upper ocean circulation in a two-way coupled wave-current model

    Institute of Scientific and Technical Information of China (English)

    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.

  8. Interactions of allogeneic human mononuclear cells in the two-way mixed leucocyte culture (MLC): influence of cell numbers, subpopulations and cyclosporin

    Science.gov (United States)

    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

  9. Comparison 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

    Directory of Open Access Journals (Sweden)

    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.

  10. 双向旋流污水净化器处理溢流污水%Treatment of overflow using two-way cyclone flocculation hydrocyclone

    Institute of Scientific and Technical Information of China (English)

    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.

  11. Aerosol indirect effect on the grid-scale clouds in the two-way coupled WRF–CMAQ: model description, development, evaluation and regional analysis

    Energy Technology Data Exchange (ETDEWEB)

    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 PM2.5 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 PM2.5 chemical composition reveals that in August, WRF–CMAQ/CAM (WRF–CMAQ/RRTMG) consistently underestimated the observed SO42- 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

  12. Theory Transmission:from One-way to Two-way%从理论的(单向)旅行到(双向)对话

    Institute of Scientific and Technical Information of China (English)

    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

  13. Rural Health Information Hub

    Science.gov (United States)

    ... issues that impact rural health in RHIhub’s Topic Guides. Recently updated: Social Determinants of Health for Rural People Browse all 50+ topics Community Health Gateway Find rural project examples in Rural Health Models and Innovations and proven strategies for strong rural programs with ...

  14. Factors Affecting Rural Facilitators’ Role: Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Bagher Kamali

    2011-03-01

    Full Text Available This study aimed to examine key factors affecting rural female facilitators’ role in participatory rural developmentin Tehran Province. Since the researchers intended to have abetter insight into the facilitators’ role and employ inquiry as alearning forum for bringing about changes for all participants,they preferred to use a case study based upon an appreciativeinquiry method. The study divided the factors affecting thefacilitators’ role into two main categories: driving factors andpreventing factors. The former are: two-way communication,election of rural eligible facilitators, participation, sense ofresponsibility, and the latter are: cultural and tribal fanaticism,lack of permanent female extension workers and frequentmanagement changes. Appreciative inquiry as a positive modeof action research could facilitate the process of education andcommunication for all stakeholders. We suggested that thereshould be a shift from the extension as a knowledge transfer tofacilitation as people’s own knowledge creation. This studyshowed that appreciative inquiry could facilitate the process ofchange and gender-awareness. This research method couldalso facilitate mutual communication between the rural facilitatorsand extension workers.

  15. Two-way and three-way approaches to ultra high performance liquid chromatography-photodiode array dataset for the quantitative resolution of a two-component mixture containing ciprofloxacin and ornidazole.

    Science.gov (United States)

    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.

  16. A large-scale assessment of two-way SNP interactions in breast cancer susceptibility using 46,450 cases and 42,461 controls from the breast cancer association consortium

    DEFF Research Database (Denmark)

    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...

  17. “双向欣赏”促进幼儿同伴关系的和谐发展%"Two-way Appreciation" to Promote the Harmonious Development of Early Childhood Peer Relationships

    Institute of Scientific and Technical Information of China (English)

    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。

  18. The Rural Development Dilemma.

    Science.gov (United States)

    Swanson, Louis E.

    1991-01-01

    Progress toward rural development has been hampered by flawed views of rural America; serious limitations to existing social and economic data on sparsely populated areas; treatment of rural America as a geographical entity unconnected to the larger U.S. economy and society; perceived lack of feasible political solution to rural problems; and…

  19. Rural-Urban Connections.

    Science.gov (United States)

    Perkins, Daniel F.; LaGreca, Anthony J.; Mullis, Ronald L.

    This publication combines three papers on rural and urban youth issues. "Key Issues Facing Rural Youth" (Daniel F. Perkins) notes that rural adolescents share the same concerns and exhibit the same problem behaviors as their urban counterparts. But in addition, geographic isolation presents problems unique to rural areas. A framework is proposed…

  20. Rural Entrepreneurship or Entrepreneurship in the Rural

    DEFF Research Database (Denmark)

    Korsgaard, Steffen; Müller, Sabine; Tanvig, Hanne Wittorff

    2015-01-01

    ” and “space” from human geography are applied to develop a nuanced understanding of rural entrepreneurship as a spatial phenomenon. Space consists of processes of movement and mobility, while places consist of localized material, social and economic relations. Findings: Two ideal types are developed, namely......Purpose: This article investigates how rural entrepreneurship engages with place and space. It explores the concept of “rural” in rural enterprise, and illustrates the importance of distinguishing between types of rural entrepreneurship. Design/methodology/approach: The constructs of “place...... (i) entrepreneurship in the rural and (ii) rural entrepreneurship. The former represents entrepreneurial activities that have limited embeddedness and enact a profit-oriented and mobile logic of space. The latter represents entrepreneurial activities that leverage local resources to re-connect place...

  1. 能量收集双向中继网络的中继选择和功率分配%Relay Selection and Power Allocation for Energy Harvesting Two-way Relay Networks

    Institute of Scientific and Technical Information of China (English)

    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。

  2. Office of Rural Health Policy

    Science.gov (United States)

    ... Information Hub Rural Health Research Gateway Rural Community Health Gateway White House Rural Council  Eligibility Analyzer Contact Us Subscribe to FORHP weekly announcement for rural health grantees and stakeholders by e-mail Subscribe to ...

  3. Rural Logistics System Based on Rural Informatization

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Current status of rural informatization construction in China,including the relatively weak rural informatization,asymmetric market information,low level of information sharing,dispersedly allocated resources and no cross point among each other are analyzed.The importance of informatization in rural logistic system is introduced:firstly,decision making of logistics system plan is based on information.Secondly,improvement of the overall efficiency of logistics system is based on information.Thirdly,logistics transmission takes the Internet as the carrier.Necessity of rural logistics system is discussed from five aspects of increasing the employment of farmers,enhancing the income of farmers,reducing the blindness of agricultural production and circulation,sharing the risks of agricultural management,and promoting the rural economic restructuring.According to the above five steps,five countermeasures are posed in order to improve the rural logistics system.The countermeasures cover the aspects of deepening the information awareness of government,establishing a rural informatization system suited to the national condition of China,strengthening the information infrastructure in rural areas,promoting the integration of rural information resources and establishing the training system for agricultural information talents.

  4. Two Ways of Learning Brand Associations

    NARCIS (Netherlands)

    S.M.J. van Osselaer (Stijn); C. Janiszewski (Chris)

    2001-01-01

    textabstractFour studies show that consumers have not one but two distinct learning processes that allow them to use brand names and other product features to predict consumption benefits. The first learning process is a relatively unfocused process in which all stimulus elements get

  5. Two-way cable television project

    Science.gov (United States)

    Wilkens, H.; Guenther, P.; Kiel, F.; Kraus, F.; Mahnkopf, P.; Schnee, R.

    1982-02-01

    The market demand for a multiuser computer system with interactive services was studied. Mean system work load at peak use hours was estimated and the complexity of dialog with a central computer was determined. Man machine communication by broadband cable television transmission, using digital techniques, was assumed. The end to end system is described. It is user friendly, able to handle 10,000 subscribers, and provides color television display. The central computer system architecture with remote audiovisual terminals is depicted and software is explained. Signal transmission requirements are dealt with. International availability of the test system, including sample programs, is indicated.

  6. Two Ways of Learning Brand Associations

    NARCIS (Netherlands)

    S.M.J. van Osselaer (Stijn); C. Janiszewski (Chris)

    2001-01-01

    textabstractFour studies show that consumers have not one but two distinct learning processes that allow them to use brand names and other product features to predict consumption benefits. The first learning process is a relatively unfocused process in which all stimulus elements get cross-reference

  7. Integration of immigrants: A two way process

    Directory of Open Access Journals (Sweden)

    Avramov Dragana

    2009-01-01

    Full Text Available This paper builds on the surveys undertaken under the FEMAGE project in eight countries (the Czech Republic, Germany, Estonia, Hungary, Austria, Poland, Slovenia, and Finland among natives on attitudes about migration and immigrants, interviews in these countries with immigrant women about their migration experiences, and policy deliberations among European stakeholders about policy options for addressing needs for immigrants in ageing societies and needs for their integration in the new home country. In this paper we have chosen to first address five critical questions: · How native and migrant women see each other? · How is need for migration viewed? · How is integration perceived? · What are the perceptions and experiences of discrimination? · Emancipation and perceptions of one's own old age, and life satisfaction Then we identify policy implications of our survey findings. Finally, we discuss policy choices and draw conclusions about needs for tailoring of integration policies based on the reflexive approach and involvement of the key policy stakeholders active in European institutions and multipliers such as international NGOs and media.

  8. Opportunity is a Two-Way Street

    Institute of Scientific and Technical Information of China (English)

    Ding Ying

    2011-01-01

    WITH a population of 900million and untouched natural resources,the continent of Africa has enormous economic potential.In a fast developing world hungry for resources many countries,around the globe,have their eyes on Africa,all keen to promote business connections.China is no exception and Chinese companies have provided a much-needed eco nomic boost and employment opportunities for many African countries in the recent past.

  9. Opportunity Is a Two-Way Street

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Chinese enterprises generate jobs for Africans while exploring the vast potential of the continent WITH a population of 900 million and untouched natural resourcces, the continent of Africa has enormous economic potential. In a fast developing world hungry for resources many countries,around the globe, have their eyes on Africa,all

  10. 对流层双向时间比对及其时延误差分析%Analysis of Two Way Troposphere Time Transfer and Its Del ay Errors

    Institute of Scientific and Technical Information of China (English)

    刘强; 孙际哲; 陈西宏; 刘继业; 张群

    2014-01-01

    双向时间比对技术广泛应用于高精度时间同步系统中,借鉴卫星双向时间比对和流星余迹双向时间比对原理,本文提出利用对流层散射通信进行双向时间比对的思想。分析对流层散射通信延迟理论及其在高精度时间比对中的重要性,研究对流层双向时间比对技术原理及其时延误差,根据选择的3个观测站的气象数据,详细分析各站在不同计算模型下的延迟误差,并设计了一种多站对流层散射双向时间比对系统。研究表明,在对流层散射双向时间比对中,散射传输时延误差是影响比对精度的最大因素,估计理论上总时延误差在12. ns左右。%Two way time transfer (TWTT) technique has been widely used in the high resolution synchronization system .The paper puts forth the idea of two way time transfer by taking advantage of troposcatter communication ,after referring to the principles of two way satellite time transfer (TWSTT) and two way meteor burst time transfer .It analyzed the delay theory in troposcatter communication and its importance in high resolution time transfer .It studied the principle of two way troposphere time transfer (TWT3 ) and its delay errors .Besides it analyzed the delay errors of three chose observation stations in details based on their meteorological data in different models and designed a multi static TWT3 (MS-TWT3 ) system .It could be concluded from the research that tropospheric delay error is the main factor to influence the resolution of transfer in TWT3 .The total del ay errors are estimated to be around 1 2. ns in theory .

  11. Optimizing Work Zones for Two-Lane Urban Road Maintenance Projects

    Institute of Scientific and Technical Information of China (English)

    HUANG Qian; SHI Jing

    2008-01-01

    Road maintenance work brings costs to the govemment and delays to users.The setting up of work zones often leads to severe congestion during peak hours,especially in busy urban areas.A road maintenance delay model is presented here that includes consideration of excessive traffic flow and non-motorists.A trial-and-error method is used to find the optimal work zone length and the best work starting time to minimize the total cost of maintenance and delays.A numerical example with a sensitivity analysis is also given.The results show that optimal starting time is not sensitive to the flow speed and the increase of work zone speeds sharply reduces the total cost when the road is congested.

  12. Analysis of Traffic Capacity on Mountainous Two Lane Highway Adding Climbing Lane

    Directory of Open Access Journals (Sweden)

    Meng Yunwei

    2016-01-01

    Full Text Available During the construction of mountainous double lane highway, climbing lane plays a certain role for enhancing the traffic capacity. In order to explore traffic capacity improvement effect for different conditions of climbing lane, 20 representative models are chosen, which contain various combinations of alignment and traffic parameters. The changes of traffic capacity, average speed, delays, and saturation in models are obtained before and after the use of a climbing lane by means of numerical simulation. The results show that the use of a climbing lane could improve traffic capacity, average speed, while reducing delays and saturation. The improvement effect is different according to different combinations of alignment and traffic parameters. The research could provide a reference for mountainous climbing lane construction intend.

  13. National Rural Health Association

    Science.gov (United States)

    ... History of Rural Health Globalization Urban Bias Dependency Theory Political Economy History of Rural Health IV: '60s ... Data Grassroots Action Center Policy Documents Legislative and Regulatory Agenda Medicaid News Response to 2013 OIG CAH ...

  14. Rural Health Disparities

    Science.gov (United States)

    ... and International Patterns , the authors found that rural American Indian and Alaska Native (AI/AN) youth have a higher mortality rate than their urban counterparts. Additionally, the rate of substance abuse admissions was higher for rural AI/AN ...

  15. Rural Education Issues: Rural Administrators Speak Out

    Science.gov (United States)

    Williams, Julia; Nierengarten, Gerry

    2010-01-01

    The purpose of this study was to identify the issues that most affect Minnesota's rural public school administrators as they attempt to fulfill the mandates required from state legislation and communities. A second purpose was to identify exemplary practices valued by individual Minnesota rural schools and districts. Electronic surveys were sent…

  16. Medicare and Rural Health

    Science.gov (United States)

    ... 1.9 million rural beneficiaries participated in Medicare Advantage (MA) and other prepaid plans, accounting for 13.4% of MA enrollees. While rural participation is not proportionate to urban participation, strong rural enrollment in ... Medicare Advantage – The ACA reduces the payments to companies providing ...

  17. 偏动式双程SMA驱动器工作机理与能量转换研究%Study on Work Mechanism and Energy Transition of the Bias Two Way SMA Actuator

    Institute of Scientific and Technical Information of China (English)

    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。

  18. Investigation of feedback on neutron kinetics and thermal hydraulics from detailed online fuel behavior modeling during a boron dilution transient in a PWR with the two-way coupled code system DYN3D-TRANSURANUS

    Energy Technology Data Exchange (ETDEWEB)

    Holt, L., E-mail: lars.holt@tuev-sued.de [TÜV SÜD Energietechnik GmbH Baden-Württemberg, Gottlieb-Daimler-Str. 7, 70794 Filderstadt (Germany); Technical University München, Department of Nuclear Engineering, Boltzmannstr. 15, D-85748 Garching bei München (Germany); Rohde, U.; Kliem, S.; Baier, S. [Helmholtz-Zentrum Dresden—Rossendorf, Reactor Safety Division, PO Box 510119, D-01314 Dresden (Germany); Seidl, M. [E.ON Kernkraft GmbH, Tresckowstr. 5, D-30457 Hannover (Germany); Van Uffelen, P. [European Commission, Joint Research Centre, Institute for Transuranium Elements, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Macián-Juan, R. [Technical University München, Department of Nuclear Engineering, Boltzmannstr. 15, D-85748 Garching bei München (Germany)

    2016-02-15

    Highlights: • General coupling interface was developed for the fuel performance code TRANSURANUS. • With this new tool simplified fuel behavior models in codes can be replaced. • The reactor dynamics code DYN3D was coupled to TRANSURANUS at assembly level. • The feedback from detailed online fuel behavior modeling is analyzed for reactivity initiated accident (RIA). • The thermal hydraulics can be affected strongly even in fresh fuel assemblies. - Abstract: Recently the reactor dynamics code DYN3D (including an internal fuel behavior model) was coupled to the fuel performance code TRANSURANUS at assembly level. The coupled code system applies the new general TRANSURANUS coupling interface, hence it can be used for one-way or two-way coupling. In the coupling, DYN3D provides process time, time-dependent rod power and thermal hydraulics conditions to TRANSURANUS, which in case of the two-way coupling approach replaces completely the internal DYN3D fuel behavior model and transfers parameters like radial fuel temperature distribution and cladding temperature back to DYN3D. For the first time results of the coupled code system are presented for a post-critical-heat-flux heat transfer. The corresponding heat transfer regime is mostly film boiling, where the cladding temperature can rise several hundreds of degrees. The simulated boron dilution transient assumed an injection of a 36 m{sup 3} slug of under-borated coolant into a German pressurized water reactor (PWR) core initiated from a sub-critical reactor state (extreme reactivity initiated accident (RIA) conditions). The feedback from detailed fuel behavior modeling was found negligible on the neutron kinetics and thermal hydraulics during the first power rise. In a later phase of the transient, the node injected energy can differ 25 J/g, even still around 20 J/g for nodes without film boiling. Furthermore, the thermal hydraulics can be affected strongly even in fresh fuel assemblies, where film boiling

  19. Explicit formulae for the two way time-transfer in the T2L2 experiment including the J2 contribution to the Earth potential in a relativistic framework

    CERN Document Server

    Minazzoli, Olivier; Samain, Etienne; Exertier, Pierre; Vrancken, Patrick; Guillemot, Philippe

    2010-01-01

    The topic of this paper is to study the two way time-transfer problem between a ground based station and a low orbit Earth's satellite, in the aim of an application to the T2L2 experiment. The sudy is driven in a fully relativistic framework. Because of the rapid increase in clock's precision/measurements, the first term beyond the Earth's potential monopolar term is explicitly taken into account. Explicit formulae, for both the distance and offset problems (definitions in the text) are proposed for the relevant applications.

  20. Rural Entrepreneurship or Entrepreneurship in the Rural

    DEFF Research Database (Denmark)

    Korsgaard, Steffen; Müller, Sabine; Tanvig, Hanne Wittorff

    2015-01-01

    Purpose: This article investigates how rural entrepreneurship engages with place and space. It explores the concept of “rural” in rural enterprise, and illustrates the importance of distinguishing between types of rural entrepreneurship. Design/methodology/approach: The constructs of “place” and ...... these processes are enabled and constrained by the immediate context or “place”. The paper weaves space and place in order to show the importance of context for entrepreneurship, which responds to the recent calls for contextualizing entrepreneurship research and theories....

  1. Two-way中继系统中基于最小化中断概率的功率分配策略%Optimal power allocation scheme based on minimizing outage probability in Two-way relay system

    Institute of Scientific and Technical Information of China (English)

    刘通; 陈前斌; 唐伦; 张力生

    2011-01-01

    为了降低Two-way中继系统中断概率,提出了一种Two-way中继系统中基于最小化中断概率的功率分配策略.首先推导了Two-way中继系统中断概率的闭合表达式,然后在总功率受限的条件下,提出了一种最小化中断概率的最优功率分配策略(OPA),通过拉格朗日乘数法对该优化模型进行了求解.仿真结果证明了该策略能够有效降低系统的中断概率,提高系统性能.%In order to decrease the outage probability of Two-way relay system, this paper proposed an optimal power allocation scheme based on minimizing outage probability. It first derived the close form of outage probability in Two-way relay system, then proposed an optimal power allocation (OPA) scheme to minimize the outage probability under the condition that total power was limited. Solved the optimal model by Lagrange multiplier method. Simulation result shows that the proposed strategy can decrease the outage probability and enhance the performance of the system.

  2. Thermoforming and Its Application in Plastics Packaging of Two Way Radio%吸塑成型及其在手持机塑料包装中的应用

    Institute of Scientific and Technical Information of China (English)

    徐中亮

    2015-01-01

    吸塑成型是一种塑料制品快速成型的方法。本文以手持机的塑料包装为研究对象,阐述了吸塑成型技术的原理和工艺,并探讨了优选热塑性材料、最优化塑料包装的结构尺寸、吸塑模具设计加工对吸塑工艺影响。从而,提高塑料包装的可靠性,延长使用寿命,降低包装的成本,并广泛应用于手持机的塑料包装设计中。%Thermoforming is a kind of method that plastics products fast forming. The article is based on plastics packaging of handheld two way radio, elaborating theory and methods of plastics forming techniques, while researching on that selecting the priority material of thermoplastic. optimizing the configuration dimension of plastics packaging, designing and processing for blister mold what they are on the influence of blister-technics. Thereby, it can highly improve product reliability, increase service life, reduce the cost price of product, widely apply for plastics packaging of two way radio.

  3. Design of cross-linked semicrystalline poly(ε-caprolactone)-based networks with one-way and two-way shape-memory properties through Diels-Alder reactions.

    Science.gov (United States)

    Raquez, Jean-Marie; Vanderstappen, Sophie; Meyer, Franck; Verge, Pierre; Alexandre, Michael; Thomassin, Jean-Michel; Jérôme, Christine; Dubois, Philippe

    2011-08-29

    Cross-linked poly(ε-caprolactone) (PCL)-based polyesterurethane (PUR) systems have been synthesized through Diels-Alder reactions by reactive extrusion. The Diels-Alder and retro-Diels-Alder reactions proved to be useful for enhancing the molecular motion of PCL-based systems, and therefore their crystallization ability, in the design of cross-linked semicrystalline polymers with one-way and two-way shape-memory properties. Successive reactions between α,ω-diol PCL (PCL(2) ), furfuryl alcohol, and methylene diphenyl 4,4'-diisocyanate straightforwardly afforded the α,ω-furfuryl PCL-based PUR systems, and subsequent Diels-Alder reactions with N,N-phenylenedimaleimide afforded the thermoreversible cycloadducts. The cross-linking density could be modulated by partially replacing PCL-diol with PCL-tetraol. Interestingly, the resulting PUR systems proved to be semicrystalline cross-linked polymers, the melting temperature of which (close to 45 °C) represented the switching temperature for their shape-memory properties. Qualitative and quantitative measurements demonstrated that these PUR systems exhibited one-way and two-way shape-memory properties depending on their cross-linking density.

  4. A large-scale assessment of two-way SNP interactions in breast cancer susceptibility using 46 450 cases and 42 461 controls from the breast cancer association consortium

    Science.gov (United States)

    Milne, Roger L.; Herranz, Jesús; Michailidou, Kyriaki; Dennis, Joe; Tyrer, Jonathan P.; Zamora, M. Pilar; Arias-Perez, José Ignacio; González-Neira, Anna; Pita, Guillermo; Alonso, M. Rosario; Wang, Qin; Bolla, Manjeet K.; Czene, Kamila; Eriksson, Mikael; Humphreys, Keith; Darabi, Hatef; Li, Jingmei; Anton-Culver, Hoda; Neuhausen, Susan L.; Ziogas, Argyrios; Clarke, Christina A.; Hopper, John L.; Dite, Gillian S.; Apicella, Carmel; Southey, Melissa C.; Chenevix-Trench, Georgia; Swerdlow, Anthony; Ashworth, Alan; Orr, Nicholas; Schoemaker, Minouk; Jakubowska, Anna; Lubinski, Jan; Jaworska-Bieniek, Katarzyna; Durda, Katarzyna; Andrulis, Irene L.; Knight, Julia A.; Glendon, Gord; Mulligan, Anna Marie; Bojesen, Stig E.; Nordestgaard, Børge G.; Flyger, Henrik; Nevanlinna, Heli; Muranen, Taru A.; Aittomäki, Kristiina; Blomqvist, Carl; Chang-Claude, Jenny; Rudolph, Anja; Seibold, Petra; Flesch-Janys, Dieter; Wang, Xianshu; Olson, Janet E.; Vachon, Celine; Purrington, Kristen; Winqvist, Robert; Pylkäs, Katri; Jukkola-Vuorinen, Arja; Grip, Mervi; Dunning, Alison M.; Shah, Mitul; Guénel, Pascal; Truong, Thérèse; Sanchez, Marie; Mulot, Claire; Brenner, Hermann; Dieffenbach, Aida Karina; Arndt, Volker; Stegmaier, Christa; Lindblom, Annika; Margolin, Sara; Hooning, Maartje J.; Hollestelle, Antoinette; Collée, J. Margriet; Jager, Agnes; Cox, Angela; Brock, Ian W.; Reed, Malcolm W.R.; Devilee, Peter; Tollenaar, Robert A.E.M.; Seynaeve, Caroline; Haiman, Christopher A.; Henderson, Brian E.; Schumacher, Fredrick; Le Marchand, Loic; Simard, Jacques; Dumont, Martine; Soucy, Penny; Dörk, Thilo; Bogdanova, Natalia V.; Hamann, Ute; Försti, Asta; Rüdiger, Thomas; Ulmer, Hans-Ulrich; Fasching, Peter A.; Häberle, Lothar; Ekici, Arif B.; Beckmann, Matthias W.; Fletcher, Olivia; Johnson, Nichola; dos Santos Silva, Isabel; Peto, Julian; Radice, Paolo; Peterlongo, Paolo; Peissel, Bernard; Mariani, Paolo; Giles, Graham G.; Severi, Gianluca; Baglietto, Laura; Sawyer, Elinor; Tomlinson, Ian; Kerin, Michael; Miller, Nicola; Marme, Federik; Burwinkel, Barbara; Mannermaa, Arto; Kataja, Vesa; Kosma, Veli-Matti; Hartikainen, Jaana M.; Lambrechts, Diether; Yesilyurt, Betul T.; Floris, Giuseppe; Leunen, Karin; Alnæs, Grethe Grenaker; Kristensen, Vessela; Børresen-Dale, Anne-Lise; García-Closas, Montserrat; Chanock, Stephen J.; Lissowska, Jolanta; Figueroa, Jonine D.; Schmidt, Marjanka K.; Broeks, Annegien; Verhoef, Senno; Rutgers, Emiel J.; Brauch, Hiltrud; Brüning, Thomas; Ko, Yon-Dschun; Couch, Fergus J.; Toland, Amanda E.; Yannoukakos, Drakoulis; Pharoah, Paul D.P.; Hall, Per; Benítez, Javier; Malats, Núria; Easton, Douglas F.

    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 susceptibility between 70 917 single nucleotide polymorphisms (SNPs) selected primarily based on prior evidence of a marginal effect. Thirty-eight international studies contributed data for 46 450 breast cancer cases and 42 461 controls of European origin as part of a multi-consortium project (COGS). First, SNPs were preselected based on evidence (P 10−10). In summary, we observed little evidence of two-way SNP interactions in breast cancer susceptibility, despite the large number of SNPs with potential marginal effects considered and the very large sample size. This finding may have important implications for risk prediction, simplifying the modelling required. Further comprehensive, large-scale genome-wide interaction studies may identify novel interacting loci if the inherent logistic and computational challenges can be overcome. PMID:24242184

  5. 基于 EPON +EoC 的广电网络双向技术改造探讨%Discussion on Modification of CATV Two-way Technology based on EPON+EoC

    Institute of Scientific and Technical Information of China (English)

    马腾霄

    2015-01-01

    近年来湖北省孝感广电网络中心积极推行有线网络改造,运用EPON+EoC 技术进行网络改造,多业务发展用户。2014年年初,孝感市城区双向网络改造基本完成,乡镇网络改造正逐步推行。分析EPON+EoC技术的优势,提出了基于EPON+EoC的广电网络双向改造技术方案。%In recent years , Hubei Province , Xiaogan radio and TV network center and actively implement the cable network transformation , network reconstruction using the technology of EPON +EoC , multi business de-velopment user .As of early 2014 , two-way network transformation in Xiaogan city basically completed the transformation of villages and towns , network is gradually carried out .This paper analyzes the advantages of EPON+EoC technology , and puts forward the CATV two-way technical transformation scheme based on EPON+EoC .

  6. Rural Poverty Rate Edges Downward.

    Science.gov (United States)

    Nord, Mark

    1997-01-01

    Although rural poverty began to decline, 1994-95, many rural households had incomes just above poverty. Rural minorities were especially disadvantaged; racial differences in educational attainment accounted for 20-33% of income gaps. One-quarter of rural children lived in poverty, most in single-parent households. Most rural poor families lived in…

  7. 基于双向近景摄影测量检测轨道平顺度的计算模型%Track Regularity Determination Model by Two-way Close-range Photogrammetry

    Institute of Scientific and Technical Information of China (English)

    陈强; 刘丽瑶; 杨莹辉; 李艳娜

    2012-01-01

    为改进高速铁路轨道几何平顺性精调的测量精度与效率,本文提出一种基于双向近景摄影测量检测轨道几何状态的方法,通过从铁路正、反向里程对轨道进行双向摄影,以轨道控制网CPⅢ作为像控点,采用严密的光束法区域网平差理论,对轨道双向摄影图像进行联合平差处理,探索出近景摄影测量检测轨道中线偏差和轨面高程的计算模型与精度评估方法.仿真试验结果双向摄影相对于单向摄影的横向与高程精度分别提高85%和42%.现场轨道试验段计算结果表明,双向近景摄影测量检测轨道的横向偏差测量精度为2.4 mm,轨面高程精度为1.7 mm,满足规范要求的轨道中线偏差与轨面高程测量精度指标,可为高速铁路轨道静态几何状态测量提供一种高效检测技术.%In order to improve the accuracy and efficiency of measuring track regularity of high-speed railways, a method of two-way photogrammetry was proposed. The track photographs were captured from two-way rails with CPIH points as exterior control points and were processed using the bundle block adjustment algorithm. The track coordinate determination model of close-range photogrammetry and accuracy assessment was theoretically presented. The simulation data show that the measurement accuracy in the transverse and vertical directions is respectively improved by 85% and 42%. The testing results in real track photogrammetry show that the accuracy in the transverse and vertical directions can reach respectively 2. 4 mm and 1. 7 mm, thus meeting the accuracy requirements for track measurement. The proposed two-way rail photogrammetry is promising for examining the static geometric track regularity of high-speed railways with high efficiency and high accuracy.

  8. Exploration of Rural Informatization and Urban-rural Information Fusion

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Based on the status quo of rural informatization and information service,this article conducts analysis and discussion of problems in rural informatization and urban-rural information fusion,using statistics. And corresponding countermeasures are put forward as follows: building rural information platform; strengthening information literacy training in rural areas and cultivating new farmers; making information network serve production and operation to increase jobs and income for farmers; developing rural e-commerce; enhancing network information security and prevention.

  9. Education for rural people

    OpenAIRE

    2015-01-01

    Nearly one out of six people in the world is suffering from hunger and illiteracy. This book was developed to assist policy makers dealing with rural poverty, food insecurity and education challenges confronting rural people. It seeks to address the correlation between education, training, empowerment and food security, mainly through a number of examples from all over the world. It is about strengthening the capacity of rural people to achieve food security. It identifies different dimension...

  10. The effect of internal and external stress on two-way shape-memory behaviour in Co{sub 49}Ni{sub 21.6}Ga{sub 29.4} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Liu, G D; Dai, X F; Luo, H Z; Liu, H Y; Meng, F B; Li, Y; Yu, X [School of Material Sciences and Engineering, Hebei University of Technology, Tianjin 300130 (China); Chen, J L; Wu, G H [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China)

    2011-02-02

    The effect of the internal stress on the two-way shape memory in Co{sub 49}Ni{sub 21.6}Ga{sub 29.4} single crystals has been investigated. We found that the internal stress generated natively by the solidifying process works as a tensile force along the growth direction. Applying different compressive pre-stresses along the [0 0 1] direction, the shape-memory strain can be continuously changed from +1.0% to -2.3%. In the [1 1 0] direction, the strain monotonically increases from -2.0% to -4.0% due to a strong detwinning produced by the consistent effect of the external and internal stresses.

  11. On the Two Ways of Style - transmission in A Dream of Red Mansions%浅析《红楼梦》英译中风格传递的两种方式

    Institute of Scientific and Technical Information of China (English)

    张鹏

    2012-01-01

    《红楼梦》因为其包含的丰富文化和语言而被誉为中国社会的"百科全书"。由霍克斯以及杨宪益夫妇所翻译的两种英译版本,在风格传递方面做出巨大贡献。本文旨在分析其中两种风格传递的方式。%A Dream of Red Mansions is regarded as the encyclopedia of Chinese society because of the richness of the cultures and the language. The two English versions translated by Hawkes and Yang Xianyi & Gladys Yang have made great contributions to the transmissions of the styles. This paper aims to give the analysis of the two ways of transmissions of the styles.

  12. Oral Health in Rural Communities

    Science.gov (United States)

    ... Guide Rural Health Topics & States Topics View more Oral Health in Rural Communities Adequate access to oral healthcare ... about oral health programs in my area? What oral health disparities are present in rural America? According to ...

  13. Tensile strain induced narrowed bandgap of TiO{sub 2} films: Utilizing the two-way shape memory effect of TiNiNb substrate and in-situ mechanical bending

    Energy Technology Data Exchange (ETDEWEB)

    Du, Minshu, E-mail: dms1223@126.com [Department of Materials Science and Engineering, China University of Petroleum at Beijing, Beijing, 102249 (China); Center for Electrochemistry, Department of Chemistry, The University of Texas at Austin, Austin, Texas, 78712 (United States); Cui, Lishan; Wan, Qiong [Department of Materials Science and Engineering, China University of Petroleum at Beijing, Beijing, 102249 (China)

    2016-05-15

    Graphical abstract: - Highlights: • Imposed tensile strain to anatase TiO{sub 2} nanofilm by using the two-way shape memory effect of NiTiNb substrate. • Imposed tensile strain to rutile TiO{sub 2} thin film by in-situ mechanical bending. • Tauc plot based on the PEC-tested auction spectrum was utilized to precisely determine the bandgap of TiO{sub 2}. • Tensile strain narrowed the bandgap of anatase TiO{sub 2} by 60 meV and rutile TiO{sub 2} by 70 meV. • Tensile strain contributes to a 1.5 times larger photocurrent for the water oxidation reaction. - Abstract: Elastic strain is one of the methods to alter the band gap of semiconductors. However, relevant experimental work is limited due to the difficulty in imposing strain. Two new methods for imposing tensile strain to TiO{sub 2} film were introduced here. One is by utilizing the two-way shape memory effect of NiTiNb substrate, and the other method is in-situ mechanical bending. The former method succeeded in imposing 0.4% tensile strain to anatase TiO{sub 2} nanofilm, and strain narrowed the bandgap of TiO{sub 2} by 60 meV. The latter method enabled rutile TiO{sub 2} thin film under the 0.5% biaxially tensile-strained state, which contributes to a narrowed bandgap with ΔE{sub g} of 70 meV. Also, photocurrents of both strained TiO{sub 2} films increased by 1.5 times compared to the strain-free films, which indirectly verified the previous DFT prediction proposed by Thulin and Guerra in 2008 that tensile strain could improve the mobility and separation of photo-excite carriers.

  14. Urbanizing rural waters

    NARCIS (Netherlands)

    Hommes, Lena; Boelens, Rutgerd

    2017-01-01

    This article studies how urbanization processes and associated rural-urban water transfers in the Lima region (Peru) create water control hierarchies that align the municipal drinking water company, hydropower plants and rural communities on unequal positions. By scrutinizing the history of water tr

  15. Energy for rural India

    NARCIS (Netherlands)

    Urban, Frauke; Benders, René M.J.; Moll, Henri C.

    2009-01-01

    About 72 million households in rural India do not have access to electricity and rely primarily on traditional biofuels. This research investigates how rural electrification could be achieved in India using different energy sources and what the effects for climate change mitigation could be We use t

  16. Ad Hoc Rural Regionalism

    Science.gov (United States)

    Hamin, Elisabeth M.; Marcucci, Daniel J.

    2008-01-01

    A new regionalism has been much documented and researched for metropolitan areas; this article documents that there is a new rural regionalism as well. In the United States, these groups appear most likely to emerge in areas that are challenged by outcomes characterizing globalization's effects on the rural condition: namely, exurban or…

  17. Urbanizing rural waters

    NARCIS (Netherlands)

    Hommes, Lena; Boelens, Rutgerd

    2017-01-01

    This article studies how urbanization processes and associated rural-urban water transfers in the Lima region (Peru) create water control hierarchies that align the municipal drinking water company, hydropower plants and rural communities on unequal positions. By scrutinizing the history of water tr

  18. Rural Credit in Vietnam

    DEFF Research Database (Denmark)

    Barslund, Mikkel Christoffer; Tarp, Finn

    This paper uses a survey of 932 rural households to uncover how the rural credit market operates in four provinces of Vietnam. Households obtain credit through formal and informal lenders, but formal loans are almost entirely for production and asset accumulation. Interest rates fell from 1997...... to credit policy is clearly inappropriate....

  19. RURAL TOURISM IN DOBRUDGEA

    Directory of Open Access Journals (Sweden)

    Elena, SIMA

    2014-11-01

    Full Text Available The natural and anthropic tourism resources of a certain area generate specific tourism forms, which complete each other within the different destination categories.The rural area in Dobrudja has diversified tourism potential, provided by the contrast of natural environment factors, ranging from the oldest and to the youngest relief units, natural protected areas, spa resources and cultural, historical, religious sites, as well as multicultural local customs and traditions of the rural area. This potential can be used under various kinds in the rural area: cultural tourism, historical tourism, religious tourism, ecotourism, fishing tourism or bird-watching tourism, and other kinds of rural tourism. By linking these tourism resources and tourism forms, tourism routes can result, which together with the local customs, traditions and cuisine may contribute to the social and economic development of Dobrudja's rural area, through sustainable tourism as alternative to seasonal seashore tourism.

  20. Multi-year downscaling application of two-way coupled WRF v3.4 and CMAQ v5.0.2 over east Asia for regional climate and air quality modeling: model evaluation and aerosol direct effects

    Directory of Open Access Journals (Sweden)

    C. Hong

    2017-06-01

    Full Text Available In this study, a regional coupled climate–chemistry modeling system using the dynamical downscaling technique was established by linking the global Community Earth System Model (CESM and the regional two-way coupled Weather Research and Forecasting – Community Multi-scale Air Quality (WRF-CMAQ model for the purpose of comprehensive assessments of regional climate change and air quality and their interactions within one modeling framework. The modeling system was applied over east Asia for a multi-year climatological application during 2006–2010, driven with CESM downscaling data under Representative Concentration Pathways 4.5 (RCP4.5, along with a short-term air quality application in representative months in 2013 that was driven with a reanalysis dataset. A comprehensive model evaluation was conducted against observations from surface networks and satellite observations to assess the model's performance. This study presents the first application and evaluation of the two-way coupled WRF-CMAQ model for climatological simulations using the dynamical downscaling technique. The model was able to satisfactorily predict major meteorological variables. The improved statistical performance for the 2 m temperature (T2 in this study (with a mean bias of −0.6 °C compared with the Coupled Model Intercomparison Project Phase 5 (CMIP5 multi-models might be related to the use of the regional model WRF and the bias-correction technique applied for CESM downscaling. The model showed good ability to predict PM2. 5 in winter (with a normalized mean bias (NMB of 6.4 % in 2013 and O3 in summer (with an NMB of 18.2 % in 2013 in terms of statistical performance and spatial distributions. Compared with global models that tend to underpredict PM2. 5 concentrations in China, WRF-CMAQ was able to capture the high PM2. 5 concentrations in urban areas. In general, the two-way coupled WRF-CMAQ model performed well for both climatological and air

  1. Multi-year downscaling application of two-way coupled WRF v3.4 and CMAQ v5.0.2 over east Asia for regional climate and air quality modeling: model evaluation and aerosol direct effects

    Science.gov (United States)

    Hong, Chaopeng; Zhang, Qiang; Zhang, Yang; Tang, Youhua; Tong, Daniel; He, Kebin

    2017-06-01

    In this study, a regional coupled climate-chemistry modeling system using the dynamical downscaling technique was established by linking the global Community Earth System Model (CESM) and the regional two-way coupled Weather Research and Forecasting - Community Multi-scale Air Quality (WRF-CMAQ) model for the purpose of comprehensive assessments of regional climate change and air quality and their interactions within one modeling framework. The modeling system was applied over east Asia for a multi-year climatological application during 2006-2010, driven with CESM downscaling data under Representative Concentration Pathways 4.5 (RCP4.5), along with a short-term air quality application in representative months in 2013 that was driven with a reanalysis dataset. A comprehensive model evaluation was conducted against observations from surface networks and satellite observations to assess the model's performance. This study presents the first application and evaluation of the two-way coupled WRF-CMAQ model for climatological simulations using the dynamical downscaling technique. The model was able to satisfactorily predict major meteorological variables. The improved statistical performance for the 2 m temperature (T2) in this study (with a mean bias of -0.6 °C) compared with the Coupled Model Intercomparison Project Phase 5 (CMIP5) multi-models might be related to the use of the regional model WRF and the bias-correction technique applied for CESM downscaling. The model showed good ability to predict PM2. 5 in winter (with a normalized mean bias (NMB) of 6.4 % in 2013) and O3 in summer (with an NMB of 18.2 % in 2013) in terms of statistical performance and spatial distributions. Compared with global models that tend to underpredict PM2. 5 concentrations in China, WRF-CMAQ was able to capture the high PM2. 5 concentrations in urban areas. In general, the two-way coupled WRF-CMAQ model performed well for both climatological and air quality applications. The coupled

  2. Rural Literacy Issues in Alberta.

    Science.gov (United States)

    Bell, James H.

    This paper reviews results of a questionnaire distributed to literacy workers in rural Alberta (Canada) to ascertain their views on rural literacy. The questionnaire was designed to identify: (1) distinctive features of the issue of adult illiteracy in rural areas; (2) the strengths of literacy efforts in rural Alberta; (3) the weaknesses of…

  3. Rural development as economic category

    OpenAIRE

    KOSTYRKO I.G.; GROMIAK T.D.

    2012-01-01

    Is conducted scientific analysis of such concepts as “steady development of village”, “development of rural territories”, “development of rural locality”, “rural development”, “steady economic development”, “economic relations”. Reasonably and the vision of determination of rural development is given from the economic point of view.

  4. 基于多点执业模式下的双向转诊制度模式的探讨%Study on Two-way Referral System Mode Based on Multi-sited Licensed Mode

    Institute of Scientific and Technical Information of China (English)

    张永; 章弦; 陈思思

    2016-01-01

    随着国家分级诊疗制度的逐步推进和完善,三级医院门诊量和住院量将受到极大影响,该文探索三级医院与区域内二级以下医院建立合作关系,由二级医院医师到三级医院多点执业,跟随患者双向转诊的模式,实现上下级医院互利共赢,提升区域医疗卫生的整体实力。%With the gradual promotion and improvement of national classification system of diagnosis and treatment, the outpatient volume and inpatient volume of the top three hospitals are greatly affected, the paper explores the correlation re-lationship between the top three hospitals and below second-class hospital within the region, the mutual benefit and win-win result of the superior-subordinate hospitals are achieved, and the overall strength of regional medical health is improved by the multi-sited license of physicians of second-class hospitals and top three hospitals and two-way referral system mode of patients.

  5. Utilization of two-way multicore cables and comparison of various electrode configurations in electrical prospecting; Denki tansa ni okeru sohokogata tashin cable no riyo to kakushu dekyoku haichi no hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Takakura, S. [Geological Survey of Japan, Tsukuba (Japan); Matsushima, J. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1996-10-01

    For more precise electrical prospecting, the new multicore cable was developed to allow high-density measurement by conventional equipment. Since conventional multicore cables are inferior in cost, length and weight, the new cable is composed of an n-conductor cable, two n-conductor male connectors and n lead wires. For connection of the multi-conductor cable and lead wires, cable sheath is peeled at n points at specific intervals. Sheath of the k-th conductor is peeled at k-th point from the terminal, and restored for insulation after connection of the conductor and lead wire. The male connectors are attached to the both ends of the multi-conductor cable. Since this two-way type cable can be used at every end, the measuring equipment can measure at one divisional point after another of a long measuring line while shifting the equipment from one point to another. All measurements are perfected only with two short cables. Resistivities were successfully measured along the long measuring line of 480m long with 97 electrodes arranged at intervals of 5m. Various electrode configurations were also compared. 1 ref., 4 figs., 2 tabs.

  6. 弹射救生装置双向传爆机构关键技术研究%Research on Key Technology of Design for Two-way Explosive Mechanism of Ejection Life-Support Set

    Institute of Scientific and Technical Information of China (English)

    段祥军; 侯世峰; 吴国建

    2015-01-01

    The technology analysis was made for strength test of two-way explosive mechanism of aircraft seat, air tightness test, ignition test and the key combination tool design and use. The process scheme design, test method, making fixture and the matters needing attention were explored. These have certain instructional significance and application to production and manufacture for the product.%对飞机座椅某型双向传爆机构强度试验、气密功能试验、试打火试验及关键组装组合工具设计使用等主要因素进行了工艺分析;对加工制造过程工艺设计、试验方法、夹具制作及注意事项进行深入探索,对于该产品生产制造具有较强的指导、应用意义。

  7. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  8. Neonatal handling decreases unconditioned anxiety, conditioned fear, and improves two-way avoidance acquisition: a study with the inbred Roman high (RHA-I- and low-avoidance (RLA-I rats of both sexes

    Directory of Open Access Journals (Sweden)

    Cristobal eRío-Alamos

    2015-07-01

    Full Text Available The present study evaluated the long-lasting effects of neonatal handling (H; administered during the first 21 days of life on unlearned and learned anxiety-related responses in inbred Roman High- (RHA-I and Low-avoidance (RLA-I rats. To this aim, untreated and neonatally-handled RHA-I and RLA-I rats of both sexes were tested in the following tests/tasks in baseline acoustic startle (BAS test, a context-conditioned fear (CCF test and the acquisition of two-way active –shuttle box- avoidance (SHAV. RLA-I rats showed higher unconditioned (NOE, ZM, BAS and conditioned (CCF, SHAV anxiety. H treatment increased exploration of the novel object in the NOE test as well as exploration of the open sections of the ZM test in both rat strains and sexes, although the effects were relatively more marked in the (high anxious RLA-I strain and in females. Neonatal handling did not affect BAS, but reduced context-conditioned fear in both strains and sexes, and improved shuttle box avoidance acquisition especially in RLA-I (and particularly in females and in female RHA-I rats. These are completely novel findings, and may suggest that H-induced changes in hippocampal function, which is enhanced in RLA-Is vs RHA-I rats, could be a candidate mechanism underlying the observed long-lasting benefits of neonatal handling on known hippocampal-dependent responses/tasks.

  9. Special Features of the Two-Way Shape Memory Effect in Stress-Assisted Aged Ti49.2Ni50.8 Single Crystals Oriented Along the [111] Direction

    Science.gov (United States)

    Panchenko, E. Yu.; Osipovich, K. S.; Chumlyakov, Yu. I.; Eftifeeva, A. S.; Maier, H.

    2017-04-01

    On the example of Ti49.2Ni50.8 (at.%) single crystals oriented along the [111]B2 directions, influence of aging at 673 and 823 K for 1 h under tensile and compressive load of 150 MPa was studied on the magnitude and sign of the two-way shape memory effect (TWSME). It is experimentally shown that the TWSME sign (tension/compression) and magnitude are determined by the size of disperse Ti3Ni4 particles, the character of interaction of the disperse particles with martensitic crystals, and the direction of external load application during aging. For one variant of nanodimensional Ti3Ni4 particles (d stress-assisted aging at 673 K for 1 h), the TWSME makes 1.3-1.7%, and the TWSME sign is independent of the direction (tension/compression) of stress application during aging: the sample size increases upon cooling and is restored upon heating. In the Ti49.2Ni50.8 [111]B2 single crystals (with particle size d = 390 nm) during stressassisted aging at 823 K for 1 h, the TWSME magnitude and sign are determined by the direction of external loading application during aging: aging under compressive loading leads to tensile TWSME with reversible strain ɛTWSME = 2.4%, and aging under tensile loading leads to compressive TWSME (ɛTWSME = -1.2%).

  10. 广电运营商应根据自身特点确定双向网改模式%The Two-way Radio television Network Reconstruction Approach Based on the Telecommunications' FTTH Mode

    Institute of Scientific and Technical Information of China (English)

    徐海泳; 劳永明

    2012-01-01

    With the speeding fusion of the three nets, the radio, television and telecommunication businesses tend to be somewhat homogeneous and severely competitive with one another. To guarantee the multi business development, both the two-way digital radio television network transformation and the telecommunications' FTTH project are under accelerated construction, preparing for the new fiber net age to come. The ultimate development scheme as the FTTH mode appears, the radio television network reconstruction must comply with its own characteristics considering its transmission architecture and the business bearing capacity.%随着三网融合步伐加快,广电与电信运营商业务趋于同质化,竞争趋于白热化。为支撑多业务发展,广电数字化双向网改和电信FTTH工程正在加速推进,逐渐向光网时代迈进,FTTH是网络发展的终极方案,但从传输架构、业务承载能力等方面分析,广电网络改造必须选择符合自身发展的模式。

  11. Rural pharmacy closures: implications for rural communities.

    Science.gov (United States)

    Todd, Kelli; Ullrich, Fred; Mueller, Keith

    2013-01-01

    Retail pharmacies provide essential services to residents of rural areas and serve many communities as the sole provider of pharmacist services. Losing the only retail pharmacy within a rural community (census designated city), and within a 10 mile radius based on driving distance ("sole community pharmacy"), may affect access to prescription and over-the-counter drugs and, in some cases, leave the community without proximate access to any clinical provider. This policy brief documents the closure of local retail pharmacies in which the pharmacist was the only clinical provider available in the community at the time the pharmacy closed. Characteristics of the community and the retail pharmacy are described. The findings may suggest future policy actions to minimize the risk or mitigate the negative consequences of pharmacy closures. Key Findings. (1) Between May 1, 2006, and October 31, 2010, 119 sole community pharmacies closed. (2) Of those 119 pharmacies, 31 were located in rural communities with no other health professionals or clinical providers. (3) In 16 states, at least 1 community lost a sole community retail pharmacy, and there was no other pharmacy within 10 miles (actual driving distance). (4) Of the 31 pharmacy closures in communities with no other providers, 17% were located in remote rural areas designated with a Rural-Urban Commuting Area (RUCA) score of 10 or higher. Such a score means that, on average, 60 minutes of travel time is required to reach an urbanized area, and 40 minutes is required to reach a large urban cluster of 20,000 population or more.

  12. Informe rural 2006

    OpenAIRE

    César Falconi; Peter Pfaumann; Nicolás Mateo; Rocío González; Alejandra Palma; José Rente Nascimento; Mark D. Wenner; María Eugenia Kyburz

    2007-01-01

    Esta edición del Informe Rural contiene siete artículos: La influenza aviar y el sector avícola de América Latina, Biocombustibles y oportunidades para el desarrollo rural, Enfoques sectoriales amplios en desarrollo rural: ¿instrumento viable para mejorar el impacto de la cooperación internacional?, Financiamiento de las cadenas agroalimentarias de valor, Cómo mejorar el clima para los negocios forestales, Avances en el Fondo Regional de Tecnología Agropecuaria (FONTAGRO) y Financiamiento rur...

  13. Changing Rural Paradigms

    DEFF Research Database (Denmark)

    Høst, Jeppe Engset

    2016-01-01

    paradigm” (OECD 2006) and its implications for ethnological scholars and practitioners of today. In the “new rural paradigm”, bottom-up processes, “place-bound” cultural and historical values are highlighted as essential to local development. This of course empowers the ethnologists, but also put us...... in a position at the very centre of a commodification of “the rural” and rural communities. The article therefore concludes with a discussion of currents trends in regional and rural development and the...

  14. Rural-urban Migration, Rural Household Income and Sustainable Development in Rural Areas of China

    Institute of Scientific and Technical Information of China (English)

    Lu Qi; Yang Chunyue; Li Juan

    2008-01-01

    The objective of this paper is to investigate the rela-tionships among rural-urban migration, rural household income and sustainable development in rural areas of China. The typical case study is done and 288 questionnaires are collected from five villages in Hebei and Guangxi provinces, China. The migration and remittance status, household income and sustainable devel-opment of rural areas are analyzed on the basis of questionnaires. Rural-urban migration is becoming a part of routine life in rural areas. And remittance is an important component in rural house-hold income. Rural-urban migration increases the arable land area per labor, which releases the tight human-land relationship in villages. In total, the migration increases the rural household in-come and accelerates the sustainable development of rural areas.

  15. Mozambique - Rural Water Supply

    Data.gov (United States)

    Millennium Challenge Corporation — This report provides the results from (1) an impact evaluation of the MCA's Rural Water Point Implementation Program ('RWPIP') in Nampula and (2) an evaluation of...

  16. Rural Veterans by State

    Data.gov (United States)

    Department of Veterans Affairs — This speadsheet contains data from the 2014 American Community Survey and shows the demographic and socioeconomic characteristics of Veterans who live in rural and...

  17. Innovating for Rural Development

    DEFF Research Database (Denmark)

    Christensen, Dorthe

    is that policies, agricultural research and extension should pay attention to these financial structural aspects, since they regulate the extent of ‘public good extension services’ like rural development services and ‘innovation intermediation’ in Danish agricultural extension agencies. The capacity differs among...... the individual agencies and among individual agents. There are agencies that financially invest in rural development service, including in innovation intermediation. On the other hand, there are agencies where the presence of rural development service is merely as a formal structure, possibly to signal...... interactions, by exploring the perspective of the participants; and the paper also seeks to understand possible constraining or supportive extension aspects at play. Paper 3 examines how the apparent change effort: ‘rural development service’ is reflected in the management strategies of individual agricultural...

  18. "Ruralizing" Presidential Job Advertisements

    Science.gov (United States)

    Leist, Jay

    2007-01-01

    Rural community college presidential job advertisements that focus on geography, politics, and culture can improve the likelihood of a good fit between the senior leader and the institution. (Contains 2 figures.)

  19. Tourism in Rural Environment

    Directory of Open Access Journals (Sweden)

    MIHAI IELENICZ

    2013-01-01

    Full Text Available Rural tourism is now determined by limited economic opportunities, poor infrastructure, low motivation to possible offers, lack of proper service guarantees. Nearly 500 Romanian villages are already tourist locations, with certain characteristics determined by a heritage item, or complex ones when multiple components lead to various activities. This paper includes a typology of tourist villages in Romania according to the types of practiced tourist activities, insisting on the use of a more comprehensive terminology: tourism in rural environment, participative and creative tourism in rural areas. Tourism becomes a system accepted in the rural environment as a real opportunity for economic development with multiple social consequences. By multiplying tourism potential to meet tourists’ demands, many villages will get tourism valences with various activities in this filed, including environment protection.

  20. "Ruralizing" Presidential Job Advertisements

    Science.gov (United States)

    Leist, Jay

    2007-01-01

    Rural community college presidential job advertisements that focus on geography, politics, and culture can improve the likelihood of a good fit between the senior leader and the institution. (Contains 2 figures.)

  1. Medicaid and Rural Health

    Science.gov (United States)

    ... programs. How does Medicaid impact rural healthcare and the economy? In many ways, Medicaid plays a larger role ... supporting the social services infrastructure; and contributing to the economy through revenue and jobs it generates.” Findings in ...

  2. Rural Health Clinics (RHCs)

    Science.gov (United States)

    ... rural healthcare organizations attract healthcare providers by posting job opportunities online by state. Candidates who are interested in ... areas may register with 3RNet to search for job opportunities. The National Health Service Corps (NHSC) provides scholarships ...

  3. 纠偏系统在双向拉伸塑料薄膜生产中的应用%Application of correction system in two-way stretch plastic film production

    Institute of Scientific and Technical Information of China (English)

    李雪明; 童帮毅; 赖福刚; 杨正昊; 马茗茗

    2014-01-01

    在双向拉伸塑料薄膜生产过程中,纠偏控制系统极大地降低了横拉脱夹、褶皱、破膜、波纹抖动等问题的概率,实现了薄膜的高速、高效生产。综合国内外纠偏控制系统的应用情况,分别从动力装置、工作原理和控制方式等三个方面展开了分析。结果表明电液压式动力装置兼有机电式动力装置高精度和气动液压式动力装置运行平稳的优点;相较于定单边纠偏模式和对比纠偏模式,定中心线纠偏模式具有更高的稳定性和工作效率;在实际应用中纠偏控制系统的控制方式应兼有自动和手动两种,自动控制方式运用于生产,而手动控制方式运用于静态测试。在双向拉伸塑料薄膜生产过程中,纠偏控制系统需针对不同的薄膜工艺、材质及生产速度选取最优应用方案。%The probabilities of transverse unclamping ,fold ,film breaking and corrugated jitter are de-creased significantly by the correction system in the two-way stretch plastic film production process , which improves film production with high speed and high efficiency .Synthesizing the foreign and inland application ,the correction system was analyzed from the aspects of power plant ,working principle and control method respectively .It shows that the electric hydraulic power plant has the high precision of electro-mechanical power plant and stable operation of pneumatic hydraulic power plant .The setting centerline mode is more stable and efficient than the setting one side mode and the contrast correction mode .The control mode of the correction system should be both automatic and manual in practical application ,using the automatic control method in production and the manual control mode in static testing .In the two-way stretch plastic film production process , the optimal correction system should meet the requirements of the different film technologies ,materials and pro-duction speeds .

  4. Theoretical Discussion on the Positive Deviation of the Negative Moment Reinforcement Protective Layer of the Continuous Two -Way Slab%双向板支座负筋保护层正偏差的理论探讨

    Institute of Scientific and Technical Information of China (English)

    崔双艳

    2014-01-01

    针对近千块现浇板支座负筋保护层厚度偏大的建筑工程质量通病现状,建立力学模型,在考虑了活荷载最不利位置及拱效应影响的基础上进行分析计算。通过分析计算得出支座负筋保护层允许正偏差大于规范要求的允许正偏差,且推算出了支座负筋保护层允许正偏差的一般计算公式及适用条件,为现浇板支座负筋保护层厚度的控制和检测提供了一定的参考价值。%According to the construction quality problem about larger thickness of thousand pieces of negative re -inforcement protection layer cast -in-place slab , the mechanical model was established , on which basis analy-sis and calculations wer carried out considering the most adversely affected position and arch effect .By the analy-sis and calculations , the result of the positive deviation of bearing negative reinforcement protection layer is more than the reguired range of specification requirements .Meanwhile the general calculation formula and the applica-ble condition of the negative moment reinforcement protective layer of the continuous two -way slab were de-duced .The results have certain reference value to control and detection of the thickness of bearing negative rein -forcement protection layer of the cast -in-place board .

  5. Further Study of the Two-way Second Language AcquisitionMode--ADiscussionwithMr.ChenJianmin%再论第二语言双向习得研究模式--兼与陈建民先生商榷

    Institute of Scientific and Technical Information of China (English)

    杨红

    2015-01-01

    This paper analyses the defects in Chen Jianmin’s paper Study Mode of Second Language Acquisition ——A Case Study of the Degree Adverb“ 更 ”in Chinese and“ も っ と ”in Japanese. There are four defects. The argument is not rigorous;the comparative analysis is not thorough;the literary styles of corpora are not consistent;reasoning is not correct. About these defects, we use effective corpora to make comparative and error analyses of Chinese and Japanese degree adverbs, and introduce the future research tasks on the two-way second language acquisition.%本文分析了陈建明先生《第二语言习得研究模式初探——以汉语程度副词“更”和日语程度副词“もっと”的分析为例》一文存在的缺陷:立论有失严谨;对比分析不深入;对比分析使用的语料库的文体不一致;推理不正确。针对文章的缺陷,本文利用有效的语料对汉日程度副词再次进行了对比分析和误用分析,并提出今后双向二语习得研究的课题。

  6. On Moral Educational Functions of Two-way Case Study Teaching Approach Based on Discourse Theory%基于商谈伦理的双向案例教学法道德教育功能和策略

    Institute of Scientific and Technical Information of China (English)

    肖岁利

    2014-01-01

    Habermas's discourse theory has important implications on our ideological and moral construction and education , the theory of two-way case teaching approach based on that theory has changed the traditional teaching of moral education model funda -mentally , moral values conducive to innovation , with a moral self-education functions , help students sincerity , respect and co-operation quality of training , but also conducive to ethical practice .By building “class Cyberspace”, teachers and students to a-chieve equality , openness , freedom of space to discuss moral consensus to form moral habits , which has a positive role on our social transition and education to build the "new morality"in a wider field .%哈贝马斯的“商谈”理论,对我们思想道德建设和教育有着重要的启示,基于商谈理论的双向案例教学法从根本上改变了传统的道德教育模式,有利于道德观念的创新,具有道德自我教育功能,有利于学生真诚、尊重和合作品质的培养,也有利于道德践行。通过构建“类赛博空间”,师生在平等、开放、自由的商谈空间中达成道德共识,形成道德习惯,这对于我们社会转型时期在更广阔领域“新道德”的构建和教育有着积极作用。

  7. Establishment and Analysis on Time Synchronization Comparison System by Two-way Satellite%基于卫星双向法的时间比对系统构建与分析

    Institute of Scientific and Technical Information of China (English)

    叶玲玲; 石明华; 楼杨

    2011-01-01

    For the high-accuracy time synchronization, the two-way satellite (TWSIT) is adopted, the time synchronization comparison system is built, and the major facts of affecting the system uncertainty are analyzed. TWSIT means that the timing synchronizes transmission and reception of the two stations. It can eliminate the errors (such as satellite position error, ionospheric delay error, troposphere delay error and satellite transponder error) caused by transmission routes. The analysis shows that in all influence factors of uncertainty, the delay instability of transmission and reception devices is a major influence component, and the time synchronization accuracy can be controlled by the system within 4 ns. The system provides an operable method for the high-accuracy time synchronization.%为了实现高精度时间同步,采用了卫星双向法,对时间比对系统进行了构建,并对影响比对系统不确定度的因素进行了分析.卫星双向法即两个台站同步发送和接收时间信号,可消除传递路径引起的误差,如:卫星位置引起的误差、电离层和对流层修正误差、卫星转发器误差.分析表明:在所有不确定度影响因素中,发射与接收设备时延的不稳定性是最大影响分量,系统对时精度可控制在4 ns以内.系统的构建为高精度时间同步提供了可操作的方法.

  8. Outage Analysis of Two-Way Single Relay Network with Hardware Impairments%硬件损伤条件下的双向单中继网络性能分析

    Institute of Scientific and Technical Information of China (English)

    沈忠良; 郭克锋

    2016-01-01

    相位噪声、I/Q支路不均衡和高功率放大下的非线性等原因会导致系统硬件损伤,而传输系统的硬件损伤会引起系统性能的损失。本文主要分析硬件损伤条件下的双向单中继网络的系统性能,所考虑的系统的所有节点都具有硬件损伤。在此基础上得到系统中断概率精确解和高信噪比下的渐近解、理论解和渐近解,客观展示了硬件损伤对系统性能的影响。同时,通过仿真验证了理论解的正确性,进一步验证了硬件损伤对系统性能的影响。%Phase noise, I/Q imbalance, and nonlinearity in HPA(high-power amplifier) condition could cause hardware impairments, and the hardware impairments of transmission system may result in great impact on system performance. The impact of hardware impairments in a two-way AF(amplify-and-forward) network is analyzed, with all the system nodes considered having hardware impairments. Based on this, the exact closed-form expression and approximate expression for the outage probability of the system are derived, thus to provide a fast means to evaluate the impact of hardware impairments. In addition, simulation results indicate the correctness of analytical results.

  9. Rural road maintenance management

    OpenAIRE

    Johannessen, B.

    1999-01-01

    This manual summarizes relevant Cambodian government policies regarding rural road maintenance. Chapter 2 defines the various components of road maintenance and describes an effective strategy and organization which addresses the maintenance requirements of rural roads in Cambodia. Chapter 3 is a brief description of the planning, implementation and reporting cycle required in an effective road maintenance management system. Chapter 4 summarizes the contracts management procedures, and finall...

  10. producto turismo rural

    Directory of Open Access Journals (Sweden)

    Blanca García Henche

    2005-01-01

    Full Text Available El turismo rural lleva un largo periodo establecido en Europa, pero en los últimos años crece su importancia ya que supone un nuevo producto turístico y una fuente de ingresos para la economía rural. Actualmente, los turistas buscan experiencias distintas al tradicional turismo de sol y playa, prefieren un turismo más individualizado y flexible, buscan nuevas formas de alojamiento y muestran un interés creciente por el contacto con la naturaleza. La oferta turística rural ha de adaptarse a las exigencias de esta demanda, lo que implica más flexibilidad y alojamientos y pueblos adaptados a las necesidades emergentes. Se ha de definir el turismo rural como una alternativa de adaptación a los cambios en las necesidades de los consumidores. El presente documento muestra los componentes del turismo rural. Los recursos turísticos son la materia prima, a la que se ha de añadir los servicios. Estos servicios pueden ser básicos o complementarios. Además de los servicios hay que añadir las actividades complementarias e infraestructuras No hay duda de que el turismo rural puede beneficiarse de la aplicación del marketing. El marketing implica entender qué es lo que los consumidores desean y crear productos para satisfacer sus necesidades, además de comercializar el producto correctamente.

  11. Rural maternity care.

    Science.gov (United States)

    Miller, Katherine J; Couchie, Carol; Ehman, William; Graves, Lisa; Grzybowski, Stefan; Medves, Jennifer

    2012-10-01

    To provide an overview of current information on issues in maternity care relevant to rural populations. Medline was searched for articles published in English from 1995 to 2012 about rural maternity care. Relevant publications and position papers from appropriate organizations were also reviewed. This information will help obstetrical care providers in rural areas to continue providing quality care for women in their communities. Recommendations 1. Women who reside in rural and remote communities in Canada should receive high-quality maternity care as close to home as possible. 2. The provision of rural maternity care must be collaborative, woman- and family-centred, culturally sensitive, and respectful. 3. Rural maternity care services should be supported through active policies aligned with these recommendations. 4. While local access to surgical and anaesthetic services is desirable, there is evidence that good outcomes can be sustained within an integrated perinatal care system without local access to operative delivery. There is evidence that the outcomes are better when women do not have to travel far from their communities. Access to an integrated perinatal care system should be provided for all women. 5. The social and emotional needs of rural women must be considered in service planning. Women who are required to leave their communities to give birth should be supported both financially and emotionally. 6. Innovative interprofessional models should be implemented as part of the solution for high-quality, collaborative, and integrated care for rural and remote women. 7. Registered nurses are essential to the provision of high-quality rural maternity care throughout pregnancy, birth, and the postpartum period. Maternity nursing skills should be recognized as a fundamental part of generalist rural nursing skills. 8. Remuneration for maternity care providers should reflect the unique challenges and increased professional responsibility faced by providers in

  12. Workforce issues in rural surgery.

    Science.gov (United States)

    Lynge, Dana Christian; Larson, Eric H

    2009-12-01

    Almost one quarter of America's population and one third of its landmass are defined as rural and served by approximately 20% of the nation's general surgeons. General surgeons are the backbone of the rural health workforce. There is significant maldistribution of general surgeons across regions and different types of rural areas. Rural areas have markedly fewer surgeons per population than the national average. The demography of the rural general surgery workforce differs substantially from the urban general surgery workforce, raising concerns about the extent to which general surgical services can be maintained in rural areas of the United States.

  13. Pedagogy for rural health.

    Science.gov (United States)

    Reid, Stephen J

    2011-04-01

    As the body of literature on rural health has grown, the need to develop a unifying theoretical framework has become more apparent. There are many different ways of seeing the same phenomenon, depending on the assumptions we make and the perspective we choose. A conceptual and theoretical basis for the education of health professionals in rural health has not yet been described. This paper examines a number of theoretical frameworks that have been used in the rural health discourse and aims to identify relevant theory that originates from an educational paradigm. The experience of students in rural health is described phenomenologically in terms of two complementary perspectives, using a geographic basis on the one hand, and a developmental viewpoint on the other. The educational features and implications of these perspectives are drawn out. The concept of a 'pedagogy of place' recognizes the importance of the context of learning and allows the uniqueness of a local community to integrate learning at all levels. The theory of critical pedagogy is also found relevant to education for rural health, which would ideally produce 'transformative' graduates who understand the privilege of their position, and who are capable of and committed to engaging in the struggles for equity and justice, both within their practices as well as in the wider society. It is proposed that a 'critical pedagogy of place,' which gives due acknowledgement to local peculiarities and strengths, while situating this within a wider framework of the political, social and economic disparities that impact on the health of rural people, is an appropriate theoretical basis for a distinct rural pedagogy in the health sciences.

  14. 不对称放大转发双向中继功率分配及中继位置选择%Optimum Power Allocation and Relay Location for Asymmetric Two-way Amplify-and-forward Relaying

    Institute of Scientific and Technical Information of China (English)

    吉晓东; 郑宝玉

    2012-01-01

    该文研究基于放大转发中继的不对称双向中继系统容量问题.首先,在瑞利衰落信道环境下,从双向通信的角度,通过理论分析得出其中断概率精确表达式和渐进表达式.理论分析发现节点发射功率和源节点目标速率共同决定系统中断概率,并且在大多数业务下系统中断性能仅取决于单向链路,而与另一链路无关.基于此,以优化系统中断性能为目标,提出一种基于业务知识的节点功率分配算法和中继位置选择算法.数值仿真实验结果表明,通过功率分配和中继位置选择可以显著提高不对称放大转发双向中继系统的中断性能.%The capacity issue of asymmetric two-way amplify-and-forward relaying is investigated. First, exact and asymptotic outage probabilities of the network scenario under investigation are derived over Rayleigh fading channels. Then, it is found that the system outage probability is determined by the terminals' average transmission powers and the traffics that the system operates. For most of the traffics, the overall system outage probability depends only on the one-way channel. Following this analysis, novel power allocation and relay location algorithms are proposed, both of which are based on the traffic-knowledge of operating networks. The simulation results show that the outage performance is significantly improved when the proposed algorithms are applied.

  15. Transceiver Design for Two-way AF MIMO Relay Systems Based on Power Consumption%基于功率的双向AF MIMO中继系统收发器设计

    Institute of Scientific and Technical Information of China (English)

    吴昊; 梁晓雯

    2016-01-01

    In view of the joint transceiver design for users and relay in multiple user pairs two-way amplify-and-forward ( AF ) multiple input multiple output ( MIMO) relay systems,and for the purpose of power saving,an optimization problem is proposed to mini-mize the total power consumption of relay and users under the mean square error (MSE) constraint of each user.Due to the non-convex-ity,it is difficult to obtain the globally optimal solution of this problem. Therefore the original problem is decomposed into three easier sub-problems,which are solved respectively. Then an iterative algorithm based on alternating optimization is proposed to solve the original problem.Simulation results show that the proposed algorithm can save the total power of users and relay effectively as compared to other algorithms.%针对多用户对双向放大转发多输入多输出中继系统中用户和中继的收发器联合设计问题,基于节省功率的目的,提出了在满足每个用户均方误差约束的条件下最小化用户和中继总功率的优化问题。由于所形成的优化问题是非凸的,难以求得全局最优解,因此将原问题分解为3个便于处理的子问题,对这3个子问题分别进行求解,在此基础上提出了一种基于交替优化的迭代算法去求解原问题。仿真结果表明,所提算法相较于其他算法可以有效地节省用户和中继的总功率。

  16. 一种斜井双向可逆钩式阻车器的设计应用%The design of slope two-way reversible hook type stopper applications

    Institute of Scientific and Technical Information of China (English)

    张杰; 翁刘基; 佘宽; 赵先才

    2016-01-01

    阻车器是用于窄轨运输,能使运动的矿车停在某一要求地点的设备。阻车器是矿井生产中不可缺少的设备,也是一种安全设备。目前许多斜井运输的上部平车场因场地受限,在同一股道上既有上行矿车也有下行矿车,要求在变坡点前的阻车器,既能保证上行矿车无障碍地上行到平车场,又要保证矿车不会因操作失误等原因随意通过阻车器进入斜井巷道发生跑车事故。现有的阻车器结构型式(如手动逆止爪式、阻轮式、钩式等)很难满足这些需求。据此,设计了一种斜井双向可逆钩式阻车器,利用液压作为动力,很好地解决了这些问题。%Stopper is used in narrow rail transportation, can make the movement of the car stopped at a particular location equipment. Stopper is indispensable equipment in the production of the mine, is also a kind of safety equipment. Now many of the upper slope transportation on flat field due to limited space, on the same track has both uplink harvesters and downward harvesters, request before changing slope point squeezer, upward harvesters barrier-free line on the ground can be ensured to flat wagon, harvesters will not by reason of error to be arbitrary and through stopper into the slope roadway sports car accident. Existing stopper structure (such as manual non-return claw type, wheel, hook type, etc.) it is difficult to meet these requirements. On this basis, we design a two-way reversible hook type inclined squeezer, using hydraulic pressure as power, solved these problems well.

  17. 氧化苦参碱对小鼠淋巴结T细胞增殖的双向作用%Two-ways effects of Oxymatrine on T lymphocyte proliferation in mouse lymph node stimulated by Con A

    Institute of Scientific and Technical Information of China (English)

    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.

  18. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  19. Medical graduates becoming rural doctors: rural background versus extended rural placement.

    Science.gov (United States)

    Clark, Tyler R; Freedman, Saul B; Croft, Amanda J; Dalton, Hazel E; Luscombe, Georgina M; Brown, Anthony M; Tiller, David J; Frommer, Michael S

    2013-12-16

    To determine whether recruitment of rural students and uptake of extended rural placements are associated with students' expressed intentions to undertake rural internships and students' acceptance of rural internships after finishing medical school, and to compare any associations. Longitudinal study of three successive cohorts (commencing 2005, 2006, 2007) of medical students in the Sydney Medical Program (SMP), University of Sydney, New South Wales, using responses to self-administered questionnaires upon entry to and exit from the Sydney Medical School and data recorded in rolls. Students' expressed intentions to undertake rural internships, and their acceptance of rural internships after finishing medical school. Data from 448 students were included. The proportion of students preferring a rural career dropped from 20.7% (79/382) to 12.5% (54/433) between entry into and exit from the SMP. A total of 98 students took extended rural placements. Ultimately, 8.1% (35/434) accepted a rural internship, although 14.5% (60/415) had indicated a first preference for a rural post. Students who had undertaken an extended rural placement were more than three times as likely as those with rural backgrounds to express a first preference for a rural internship (23.9% v 7.7%; χ(2) = 7.04; P = 0.008) and more than twice as likely to accept a rural internship (21.3% v 9.9%; χ(2) = 3.85; P = 0.05). For the three cohorts studied, rural clinical training through extended placements in rural clinical schools had a stronger association than rural background with a preference for, and acceptance of, rural internship.

  20. Rural Science Education Program

    Energy Technology Data Exchange (ETDEWEB)

    Intress, C. [New Mexico Museum of Natural History and Science, Albuquerque, NM (United States)

    1994-12-31

    The Rural Science Education Project is an outreach program of the New Mexico Museum of Natural History and Science with the goal of helping rural elementary schools improve science teaching and learning by using local natural environmental resources. This program is based on the assumption that rural schools, so often described as disadvantaged in terms of curricular resources, actually provide a science teaching advantage because of their locale. The natural environment of mountains, forests, ponds, desert, or fields offers a context for the study of scientific concepts and skills that appeals to many youngsters. To tap these resources, teachers need access to knowledge about the rural school locality`s natural history. Through a process of active participation in school-based workshops and field site studies, teachers observe and learn about the native flora, fauna, geology, and paleontology of their community. In addition, they are exposed to instructional strategies, activities, and provided with materials which foster experimential learning. This school-museum partnership, now in its fifth year, has aided more than 800 rural teachers` on-going professional development. These educators have, in turn, enhanced science education throughout New Mexico for more than 25,000 students.

  1. Agriculture and Rurality: Beginning the "Final Separation"?

    Science.gov (United States)

    Friedland, William H.

    2002-01-01

    When is a farm a farm? When is rural rural? Has the issue of the rural-urban continuum returned? Decades ago rural sociology worked itself into two blind alleys: rural-urban differences and attempts to define the rural-urban fringe. Although these conceptual problems eventually were exhausted, recent developments in California raise the…

  2. Researching Rural Places: On Social Justice and Rural Education

    Science.gov (United States)

    Roberts, Philip; Green, Bill

    2013-01-01

    This paper explores some of the political and methodological challenges involved in researching rural education. It begins by outlining the situation in Australia regarding the relationship between social justice and rural education. It first describes the disadvantages experienced by many rural communities and presents an analysis of rural…

  3. About The Rural Development Foundation

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>The Rural Development Foundation (RDF) ,founded in 1996,is an Indian nonprofit organization with the mission of providing quality education for underprivileged rural children. RDF founded and continues to operate five schools and one junior college in Andhra

  4. About The Rural Development Foundation

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>The Rural Development Foundation ( RDF) ,founded in 1996,is an Indian nonprofit organization with the mission of providin gquality education for underprivileged rural children. RDF founded and continues to operate five schools and one junior college in

  5. About The Rural Development Foundation

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>The Rural Development Foundation ( RDF) ,founded in 1996,is an Indian nonprofit organization with the mission of providing quality education for underprivileged rural children. RDF founded and continues to operate five schools

  6. About The Rural Development Foundation

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>The Rural Development Foundation ( RDF) ,founded in 1996,is an Indian nonprofit organization with the mission of providing quality education for underprivileged rural children. RDF founded and continues to operate five schools and one junior college in

  7. About The Rural Development Foundation

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>The Rural Development Foundation(RDF),founded in1996,is an Indian nonprofit organization with the mission of providingquality education for underprivileged rural children.RDF founded and continues to operate five schools and one junior college in

  8. Organizing Rural Health Care

    DEFF Research Database (Denmark)

    Bunkenborg, Mikkel

    2012-01-01

    The liberalization of health care in the course of three decades of ‘reform and opening up’ has given people in rural China access to a diverse range of treatment options, but the health care system has also been marred by accusations of price hikes, fake pharmaceuticals, and medical malpractice....... This chapter offers an ethnographic description of health as an issue in a Hebei township and it focuses on a popular and a statist response to the perceived inadequacy of the rural health care system. The revival of religious practices in rural China is obviously motivated by many factors, but in the township...... in question, various forms of healing play a significant role in religious movements and the rising cost of medical services as well as a general distrust of formal medical institutions seem to be part of the reason why people choose to follow spirit mediums and religious movements that offer alternative...

  9. Social Welfare in Rural Europe.

    Science.gov (United States)

    Shucksmith, Mark; And Others

    1994-01-01

    Literature review on social exclusion and disadvantage in rural Europe suggests that rural poverty arises from unemployment, low wages, and, most significantly, inadequate income in old age. Discusses difficulties in identifying rural incidence of exclusion and disadvantage, as well as the need for such research in light of major ongoing social…

  10. Interdisciplinarity and young rural researchers

    NARCIS (Netherlands)

    Derkzen, P.H.M.; Mustakangas, E.; Gambino, M.; Kucerova, E.

    2006-01-01

    The European Society for Rural Sociology (ESRS) organised a round table discussion for young rural researchers at the XXI ESRS Congress, 22-26 August, 2005 in Keszthely, Hungary. In the discussion, participants focused on interdisciplinarity in rural research from their own personal points of view b

  11. Planning Schools for Rural Communities.

    Science.gov (United States)

    Harmon, Hobart; Howley, Craig; Smith, Charles; Dickens, Ben

    School improvement in rural places cannot succeed without attention to the rural context of learning. Most especially, smaller schools need to be preserved and sustained in rural areas, particularly impoverished communities, for the sake of student achievement and personal development. This school improvement tool suggests the character of a "good…

  12. Juvenile Justice in Rural America.

    Science.gov (United States)

    Jankovic, Joanne, Ed.; And Others

    Producing a much-needed organized body of literature about rural juvenile justice, 14 papers (largely from the 1979 National Symposium on Rural Justice) are organized to identify current issues, identify forces causing changes in current systems, review programs responding to rural juvenile justice problems, and provide planning models to aid…

  13. 基于三维重建数据的双向点云去噪方法研究%Two-way point cloud denoising method based on three-dimensional reconstruction data

    Institute of Scientific and Technical Information of China (English)

    刘辉; 王伯雄; 任怀艺; 罗秀芝

    2013-01-01

    In reverse engineering, reconstruction of the 3D point cloud data is the key step to the final profile of the object. How to remove the noise data from the complex point cloud data is the focus of the research. In this paper, the data according to the different types of noise in measurement environment are analyzed. The noise points for the outside contours of the object is removed using human-computer interaction, the single obvious noise point for the inside contours of the object is removed using adjacent points weighted average method, and the continuous wrong noise points for the inside contours of the object is removed using two-way denoising method. In the vertical direction of the point cloud, the ups and downs of the obvious noise point is removed using the inclination between the adjacent points. In the horizontal direction of the point cloud, the horizontal distance of the rest of the point cloud is adjusted by weighted averaging of horizontal distance of the adjacent point cloud data. Finally, the three-dimensional coordinates at the denoising points are got using least square method. The results show that this method is not only effective to remove the noise which are included in the point cloud data, but also to adjust and modify the distortion of the data about the surface, and to obtain a continuous smooth surface.%逆向工程中,三维点云数据的重构是最终获取物体形貌的关键一环,如何从复杂的点云中去除噪声干扰是人们一直研究的重点.根据测量环境中产生的不同类型噪声数据进行分析,对于物体轮廓外的噪声点,采用人机交互的方式直接去除噪声点,对于物体轮廓内单个明显的噪声点采用相邻点加权平均的方法去除,而对轮廓内连续错误的噪声点,采用了双向去噪的方法,即在点云的垂直方向通过相邻点夹角的大小去除起伏明显的噪声点,在点云的水平方向通过相邻点云水平距离的加权平均来调整水平

  14. Social Construction: the Reconstruction of China's Interests Pattern in Two--way of Movement%社会建设:双向运动中的中国利益格局重建

    Institute of Scientific and Technical Information of China (English)

    贾玉娇

    2012-01-01

    在社会转型初期,自由市场逻辑主导下的社会变革激发了社会活力,释放出了巨大能量,但也因利益在社会成员中的不均衡分布而产生对经济发展公平性的质疑。伴随市场力量的不断强大,社会自我保护力不断增强,使得社会矛盾呈愈演愈烈之势。在世界社会治理机制由一元向多元转变的趋势下,中国也开启了社会治理机制的变革之路,其核心议题在于建构何种国家、市场与社会力量的分配格局。这对于深化中国社会转型进程,实现社会稳定有序,奠定社会管理的社会基础具有十分重要的意义。然而,如何进行社会建设,不能给出简单的、想当然的结论,而需要挖掘其背后的支配逻辑——双向运动,以此重塑国家、市场与社会三者之间的关系。%Beginning of the transition in society, social change under the guidance of free market logic in- spired social vitality, releasing tremendous energy, but also because of the interests of the uneven distribu- tion in members of society which have questioned the fairness of economic development. With market forces the continuing strong, social self--protection forces continue to enhance, making the social conflict was getting worse. In the trend of mechanism of social governance in the world from the one to multiple changes, China has also opened a community change; the core issue is what kind of building the distribu- tion pattern of state, market and social forces. It is of great significance for deepening of China's social transformation process ,in order to achieve social stability and lay the social foundation of social manage- ment . However, how to build the society can not provide simple conclusion, but need to dig behind the dominant logic -- two--way movement, remodeling the relationship between government, market and so- ciety to this.

  15. Beamforming Design of AF MIMO Two-Way Relay Channels Based on MSMSE%基于MSMSE的MIMO放大转发双向中继信道中波束成形设计

    Institute of Scientific and Technical Information of China (English)

    王梓斌; 向良军; 郑林华; 丁宏

    2011-01-01

    本文主要研究了基于最小化均方误差和准则的MIMO放大转发双向中继信道中的波束成形向量(矩阵)的设计.我们分别在集中式与分布式两种应用环境中提出了一套解决方案.在集中式方案中,多个中继之间完全协作,因此将多个单天线中继等效成一个多天线的中继节点,设计了基于所有中继天线的总功率控制的波束成形向量(矩阵).在分布式方案中,中继节点之间无协作,分别设计了基于所有中继总功率控制波束成形向量(矩阵)和基于单个中继功率控制的波束成形向量(矩阵).仿真表明,通过波束成形设计,可以显著提高通信节点平均误码率.由于中继节点之间的完全协作,集中式方案要优于分布式方案.但是,由于中继结构简单,分布式方案更易于在实践中应用.%In this paper, we design the beamforming in multiple-input multiple-output ( MIMO) two-way relay channels to minimize the sum mean squared errors (SMSE). Two source nodes communicate to each other with the help of multiple relays each with a single antenna. A scheme for a centralized model and another scheme for distributed model are proposed, respectively. In the first scheme, relays are assumed to be able to fully cooperate with each other and the multiple relay nodes can be equivalent to a single relay with multiple antennas. Relay beamforming under total power constraint of all relays is unitedly designed with the transmit beamforming and the receive beamforming. In the aecond scheme, there are no coopenration between relay nodes , and beamforming schemes under relay total power constraint and individual power constraint are designed, respectively. the simulation results show that beamforming at source and relay nodes significantly improve the average bit error rate (BER) performance. Furthermore, with cooperation across different relays, the performance of the centralized scheme is better than the distributed one, but the

  16. Rural Mental Health Ecology

    DEFF Research Database (Denmark)

    Wilson, Rhonda L.; Wilson, G. Glenn; Usher, Kim

    2015-01-01

    The mental health of people in rural communities is influenced by the robustness of the mental health ecosystem within each community. Theoretical approaches such as social ecology and social capital are useful when applied to the practical context of promoting environmental conditions which...... maximise mental health helping capital to enhance resilience and reduce vulnerably as a buffer for mental illness. This paper explores the ecological conditions that affect the mental health and illness of people in rural communities. It proposes a new mental health social ecology framework that makes full...

  17. Rural Credit in Vietnam

    DEFF Research Database (Denmark)

    Barslund, Mikkel Christoffer; Tarp, Finn

    This paper uses a survey of 932 rural households to uncover how the rural credit market operates in four provinces of Vietnam. Households obtain credit through formal and informal lenders, but formal loans are almost entirely for production and asset accumulation. Interest rates fell from 1997...... to 2002, reflecting increased market integration; but the determinants of formal and informal credit demand are distinct. Credit rationing depends on education and credit history, but we find no evidence of a bias against women. Regional differences are striking, and a ‘one size fits all’ approach...

  18. Rural energy and development

    Energy Technology Data Exchange (ETDEWEB)

    Stern, R.

    1997-12-01

    The author discusses the worldwide problem and need for rural electrification to support development. He points out that rural areas will pay high rates to receive such services, but cannot afford the capital cost for conventional services. The author looks at this problem from the point of energy choices, subsides, initial costs, financing, investors, local involvement, and governmental actions. In particular he is concerned with ways to make better use of biofuels, to promote sustainable harvesting, and to encourage development of more modern fuels.

  19. Intergenerational Exchange of Resources and Elderly Support in Rural China.

    Science.gov (United States)

    Lin, Zhiyong; Pei, Xiaomei

    2016-07-01

    This study examines how parental investments on children affect elderly support, and how this effect is contingent on emotional closeness or parental authority. Data collected from 770 elderly parents residing in rural China were analyzed. We gathered dichotomous data for (a) whether parents invested on their children via financial or instrumental means (i.e., parental investments) and (b) whether parents reported closeness to their children (i.e., emotional closeness) and whether children respected them (i.e., parental authority). We examined the relation between these variables and children's elderly support (financial, instrumental, and emotional). We tested models in two ways, one examining the direct effect of investments, and another testing the interactions between investments and closeness or authority. We first found that investments were not directly associated with elderly support, although the closeness and authority were. Additionally, the association between investments and support was found within parents who reported authority or closeness with their children.

  20. Teachers as Rural Educators

    Science.gov (United States)

    Kristiansen, Andrew

    2014-01-01

    In the article, education is seen as a hierarchical cultural encounter between urban and rural values and ways of life. Good teachers do not only deliver curriculum, they also consider the needs and values of their students, as well as those of the local community. The article discusses how teachers' competence, knowledge and attitudes can affect…