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Sample records for distributed consensus averaging

  1. Fastest Distributed Consensus Averaging Problem on Chain of Rhombus Networks

    CERN Document Server

    Jafarizadeh, Saber

    2010-01-01

    Distributed consensus has appeared as one of the most important and primary problems in the context of distributed computation and it has received renewed interest in the field of sensor networks (due to recent advances in wireless communications), where solving fastest distributed consensus averaging problem over networks with different topologies is one of the primary problems in this issue. Here in this work analytical solution for the problem of fastest distributed consensus averaging algorithm over Chain of Rhombus networks is provided, where the solution procedure consists of stratification of associated connectivity graph of the network and semidefinite programming, particularly solving the slackness conditions, where the optimal weights are obtained by inductive comparing of the characteristic polynomials initiated by slackness conditions. Also characteristic polynomial together with its roots corresponding to eigenvalues of weight matrix including SLEM of network is determined inductively. Moreover t...

  2. A simple consensus algorithm for distributed averaging in random geographical networks

    Indian Academy of Sciences (India)

    Mahdi Jalili

    2012-09-01

    Random geographical networks are realistic models for wireless sensor networks which are used in many applications. Achieving average consensus is very important in sensor networks and the faster the consensus is, the durable the sensors’ life, and thus, the better the performance of the network. In this paper we compared the performance of a number of linear consensus algorithms with application to distributed averaging in random geographical networks. Interestingly, the simplest algorithm – where only the degree of receiving nodes is needed for the averaging – had the best performance in terms of the consensus time. Furthermore, we proved that the network has guaranteed convergence with this simple algorithm.

  3. Fastest Distributed Consensus Averaging Problem on Perfect and Complete n-ary Tree networks

    CERN Document Server

    Jafarizadeh, Saber

    2010-01-01

    Solving fastest distributed consensus averaging problem (i.e., finding weights on the edges to minimize the second-largest eigenvalue modulus of the weight matrix) over networks with different topologies is one of the primary areas of research in the field of sensor networks and one of the well known networks in this issue is tree network. Here in this work we present analytical solution for the problem of fastest distributed consensus averaging algorithm by means of stratification and semidefinite programming, for two particular types of tree networks, namely perfect and complete n-ary tree networks. Our method in this paper is based on convexity of fastest distributed consensus averaging problem, and inductive comparing of the characteristic polynomials initiated by slackness conditions in order to find the optimal weights. Also the optimal weights for the edges of certain types of branches such as perfect and complete n-ary tree branches are determined independently of rest of the network.

  4. Optimal Weights of Certain Branches of an Arbitrary Connected Network for Fastest Distributed Consensus Averaging Problem

    CERN Document Server

    Jafarizadeh, Saber

    2010-01-01

    Solving fastest distributed consensus averaging problem over networks with different topologies has been an active area of research for a number of years. The main purpose of distributed consensus averaging is to compute the average of the initial values, via a distributed algorithm, in which the nodes only communicate with their neighbors. In the previous works full knowledge about the network's topology was required for finding optimal weights and convergence rate of network, but here in this work for the first time the optimal weights are determined analytically for the edges of certain types of branches, namely path branch, lollipop branch, semi-complete Branch and Ladder branch independent of the rest of network. The solution procedure consists of stratification of associated connectivity graph of branch and Semidefinite Programming (SDP), particularly solving the slackness conditions, where the optimal weights are obtained by inductive comparing of the characteristic polynomials initiated by slackness c...

  5. Event-Triggered Distributed Average Consensus Over Directed Digital Networks With Limited Communication Bandwidth.

    Science.gov (United States)

    Li, Huaqing; Chen, Guo; Huang, Tingwen; Dong, Zhaoyang; Zhu, Wei; Gao, Lan

    2016-12-01

    In this paper, we consider the event-triggered distributed average-consensus of discrete-time first-order multiagent systems with limited communication data rate and general directed network topology. In the framework of digital communication network, each agent has a real-valued state but can only exchange finite-bit binary symbolic data sequence with its neighborhood agents at each time step due to the digital communication channels with energy constraints. Novel event-triggered dynamic encoder and decoder for each agent are designed, based on which a distributed control algorithm is proposed. A scheme that selects the number of channel quantization level (number of bits) at each time step is developed, under which all the quantizers in the network are never saturated. The convergence rate of consensus is explicitly characterized, which is related to the scale of network, the maximum degree of nodes, the network structure, the scaling function, the quantization interval, the initial states of agents, the control gain and the event gain. It is also found that under the designed event-triggered protocol, by selecting suitable parameters, for any directed digital network containing a spanning tree, the distributed average consensus can be always achieved with an exponential convergence rate based on merely one bit information exchange between each pair of adjacent agents at each time step. Two simulation examples are provided to illustrate the feasibility of presented protocol and the correctness of the theoretical results.

  6. Quantized average consensus with delay

    NARCIS (Netherlands)

    Jafarian, Matin; De Persis, Claudio

    2012-01-01

    Average consensus problem is a special case of cooperative control in which the agents of the network asymptotically converge to the average state (i.e., position) of the network by transferring information via a communication topology. One of the issues of the large scale networks is the cost of co

  7. Discontinuities and hysteresis in quantized average consensus

    NARCIS (Netherlands)

    Ceragioli, Francesca; Persis, Claudio De; Frasca, Paolo

    2011-01-01

    We consider continuous-time average consensus dynamics in which the agents’ states are communicated through uniform quantizers. Solutions to the resulting system are defined in the Krasowskii sense and are proven to converge to conditions of ‘‘practical consensus’’. To cope with undesired chattering

  8. Fastest Distributed Consensus on Petal Networks

    CERN Document Server

    Jafarizadeh, Saber

    2010-01-01

    Providing an analytical solution for the problem of finding Fastest Distributed Consensus (FDC) is one of the challenging problems in the field of sensor networks. Here in this work we present analytical solution for the problem of fastest distributed consensus averaging algorithm by means of stratification and semi-definite programming, for two particular types of Petal networks, namely symmetric and Complete Cored Symmetric (CCS) Petal networks. Our method in this paper is based on convexity of fastest distributed consensus averaging problem, and inductive comparing of the characteristic polynomials initiated by slackness conditions in order to find the optimal weights. Also certain types of leaves are introduced along with their optimal weights which are not achievable by the method used in this work if these leaves are considered individually.

  9. Dynamic Average Consensus and Consensusability of General Linear Multiagent Systems with Random Packet Dropout

    Directory of Open Access Journals (Sweden)

    Wen-Min Zhou

    2013-01-01

    Full Text Available This paper is concerned with the consensus problem of general linear discrete-time multiagent systems (MASs with random packet dropout that happens during information exchange between agents. The packet dropout phenomenon is characterized as being a Bernoulli random process. A distributed consensus protocol with weighted graph is proposed to address the packet dropout phenomenon. Through introducing a new disagreement vector, a new framework is established to solve the consensus problem. Based on the control theory, the perturbation argument, and the matrix theory, the necessary and sufficient condition for MASs to reach mean-square consensus is derived in terms of stability of an array of low-dimensional matrices. Moreover, mean-square consensusable conditions with regard to network topology and agent dynamic structure are also provided. Finally, the effectiveness of the theoretical results is demonstrated through an illustrative example.

  10. A Study On Distributed Model Predictive Consensus

    CERN Document Server

    Keviczky, Tamas

    2008-01-01

    We investigate convergence properties of a proposed distributed model predictive control (DMPC) scheme, where agents negotiate to compute an optimal consensus point using an incremental subgradient method based on primal decomposition as described in Johansson et al. [2006, 2007]. The objective of the distributed control strategy is to agree upon and achieve an optimal common output value for a group of agents in the presence of constraints on the agent dynamics using local predictive controllers. Stability analysis using a receding horizon implementation of the distributed optimal consensus scheme is performed. Conditions are given under which convergence can be obtained even if the negotiations do not reach full consensus.

  11. Order-Optimal Consensus through Randomized Path Averaging

    CERN Document Server

    Benezit, F; Thiran, P; Vetterli, M

    2008-01-01

    Gossip algorithms have recently received significant attention, mainly because they constitute simple and robust message-passing schemes for distributed information processing over networks. However for many topologies that are realistic for wireless ad-hoc and sensor networks (like grids and random geometric graphs), the standard nearest-neighbor gossip converges as slowly as flooding ($O(n^2)$ messages). A recently proposed algorithm called geographic gossip improves gossip efficiency by a $\\sqrt{n}$ factor, by exploiting geographic information to enable multi-hop long distance communications. In this paper we prove that a variation of geographic gossip that averages along routed paths, improves efficiency by an additional $\\sqrt{n}$ factor and is order optimal ($O(n)$ messages) for grids and random geometric graphs. We develop a general technique (travel agency method) based on Markov chain mixing time inequalities, which can give bounds on the performance of randomized message-passing algorithms operating...

  12. Sampled-data based average consensus with measurement noises:convergence analysis and uncertainty principle

    Institute of Scientific and Technical Information of China (English)

    LI Tao; ZHANG JiFeng

    2009-01-01

    In this paper,sampled-data based average-consensus control is considered for networks consisting of continuous-time first-order Integrator agents in a noisy distributed communication environment.The Impact of the sampling size and the number of network nodes on the system performances is analyzed.The control input of each agent can only use information measured at the sampling instants from its neighborhood rather than the complete continuous process,and the measurements of its neighbors'states are corrupted by random noises.By probability limit theory and the property of graph Laplacian matrix,it is shown that for a connected network,the static mean square error between the individual state and the average of the Initial states of all agents can be made arbitrarily small,provided the sampling size is sufficiently small.Furthermore,by properly choosing the consensus gains,almost sure consensus can be achieved.It is worth pointing out that an uncertainty principle of Gaussian networks is obtained,which implies that in the case of white Gausslan noises,no matter what the sampling size is,the product of the steady-state and transient performance indices is always equal to or larger than a constant depending on the noise intensity,network topology and the number of network nodes.

  13. Ensemble distribution models in conservation prioritization: from consensus predictions to consensus reserve networks

    Science.gov (United States)

    Meller, Laura; Cabeza, Mar; Pironon, Samuel; Barbet-Massin, Morgane; Maiorano, Luigi; Georges, Damien; Thuiller, Wilfried

    2014-01-01

    Aim Conservation planning exercises increasingly rely on species distributions predicted either from one particular statistical model or, more recently, from an ensemble of models (i.e. ensemble forecasting). However, it has not yet been explored how different ways of summarizing ensemble predictions affect conservation planning outcomes. We evaluate these effects and compare commonplace consensus methods, applied before the conservation prioritization phase, to a novel method that applies consensus after reserve selection. Location Europe. Methods We used an ensemble of predicted distributions of 146 Western Palaearctic bird species in alternative ways: four different consensus methods, as well as distributions discounted with variability, were used to produce inputs for spatial conservation prioritization. In addition, we developed and tested a novel method, in which we built 100 datasets by sampling the ensemble of predicted distributions, ran a conservation prioritization analysis on each of them and averaged the resulting priority ranks. We evaluated the conservation outcome against three controls: (i) a null control, based on random ranking of cells; (2) the reference solution, based on an expert-refined dataset; and (3) the independent solution, based on an independent dataset. Results Networks based on predicted distributions were more representative of rare species than randomly selected networks. Alternative methods to summarize ensemble predictions differed in representativeness of resulting reserve networks. Our novel method resulted in better representation of rare species than pre-selection consensus methods. Main conclusions Retaining information about the variation in the predicted distributions throughout the conservation prioritization seems to provide better results than summarizing the predictions before conservation prioritization. Our results highlight the need to understand and consider model-based uncertainty when using predicted

  14. Average Consensus Problems in Networks of Agents with Fixed and Switching Topology and Unknown Control Direction

    Directory of Open Access Journals (Sweden)

    Caixian Sun

    2014-01-01

    Full Text Available This paper is devoted to the average consensus problems in directed networks of agents with unknown control direction. In this paper, by using Nussbaum function techniques and Laplacian matrix, novel average consensus protocols are designed for multiagent systems with unknown control direction in the cases of directed networks with fixed and switching topology. In the case of switching topology, the disagreement vector is utilized. Finally, simulation is provided to demonstrate the effectiveness of our results.

  15. A Solution to Fastest Distributed Consensus Problem for Generic Star & K-cored Star Networks

    CERN Document Server

    Jafarizadeh, Saber

    2012-01-01

    Distributed average consensus is the main mechanism in algorithms for decentralized computation. In distributed average consensus algorithm each node has an initial state, and the goal is to compute the average of these initial states in every node. To accomplish this task, each node updates its state by a weighted average of its own and neighbors' states, by using local communication between neighboring nodes. In the networks with fixed topology, convergence rate of distributed average consensus algorithm depends on the choice of weights. This paper studies the weight optimization problem in distributed average consensus algorithm. The network topology considered here is a star network where the branches have different lengths. Closed-form formulas of optimal weights and convergence rate of algorithm are determined in terms of the network's topological parameters. Furthermore generic K-cored star topology has been introduced as an alternative to star topology. The introduced topology benefits from faster con...

  16. Wireless sensor networks distributed consensus estimation

    CERN Document Server

    Chen, Cailian; Guan, Xinping

    2014-01-01

    This SpringerBrief evaluates the cooperative effort of sensor nodes to accomplish high-level tasks with sensing, data processing and communication. The metrics of network-wide convergence, unbiasedness, consistency and optimality are discussed through network topology, distributed estimation algorithms and consensus strategy. Systematic analysis reveals that proper deployment of sensor nodes and a small number of low-cost relays (without sensing function) can speed up the information fusion and thus improve the estimation capability of wireless sensor networks (WSNs). This brief also investiga

  17. A Decentralized Eigenvalue Computation Method for Spectrum Sensing Based on Average Consensus

    Science.gov (United States)

    Mohammadi, Jafar; Limmer, Steffen; Stańczak, Sławomir

    2016-07-01

    This paper considers eigenvalue estimation for the decentralized inference problem for spectrum sensing. We propose a decentralized eigenvalue computation algorithm based on the power method, which is referred to as generalized power method GPM; it is capable of estimating the eigenvalues of a given covariance matrix under certain conditions. Furthermore, we have developed a decentralized implementation of GPM by splitting the iterative operations into local and global computation tasks. The global tasks require data exchange to be performed among the nodes. For this task, we apply an average consensus algorithm to efficiently perform the global computations. As a special case, we consider a structured graph that is a tree with clusters of nodes at its leaves. For an accelerated distributed implementation, we propose to use computation over multiple access channel (CoMAC) as a building block of the algorithm. Numerical simulations are provided to illustrate the performance of the two algorithms.

  18. Distributed consensus and fault tolerance - Lecture 2

    CERN Document Server

    CERN. Geneva

    2017-01-01

    In a world where clusters with thousands of nodes are becoming commonplace, we are often faced with the task of having them coordinate and share state. As the number of machines goes up, so does the probability that something goes wrong: a node could temporarily lose connectivity, crash because of some race condition, or have its hard drive fail. What are the challenges when designing fault-tolerant distributed systems, where a cluster is able to survive the loss of individual nodes? In this lecture, we will discuss some basics on this topic (consistency models, CAP theorem, failure modes, byzantine faults), detail the raft consensus algorithm, and showcase an interesting example of a highly resilient distributed system, bitcoin.

  19. Distributed consensus and fault tolerance - Lecture 1

    CERN Document Server

    CERN. Geneva

    2017-01-01

    In a world where clusters with thousands of nodes are becoming commonplace, we are often faced with the task of having them coordinate and share state. As the number of machines goes up, so does the probability that something goes wrong: a node could temporarily lose connectivity, crash because of some race condition, or have its hard drive fail. What are the challenges when designing fault-tolerant distributed systems, where a cluster is able to survive the loss of individual nodes? In this lecture, we will discuss some basics on this topic (consistency models, CAP theorem, failure modes, byzantine faults), detail the raft consensus algorithm, and showcase an interesting example of a highly resilient distributed system, bitcoin.

  20. Fastest Distributed Consensus on Star-Mesh Hybrid Sensor Networks

    CERN Document Server

    Jafarizadeh, Saber

    2010-01-01

    Solving Fastest Distributed Consensus (FDC) averaging problem over sensor networks with different topologies has received some attention recently and one of the well known topologies in this issue is star-mesh hybrid topology. Here in this work we present analytical solution for the problem of FDC algorithm by means of stratification and semidefinite programming, for the Star-Mesh Hybrid network with K-partite core (SMHK) which has rich symmetric properties. Also the variations of asymptotic and per step convergence rate of SMHK network versus its topological parameters have been studied numerically.

  1. Average Consensus in Multiagent Systems with the Problem of Packet Losses When Using the Second-Order Neighbors’ Information

    Directory of Open Access Journals (Sweden)

    Mei Yu

    2014-01-01

    Full Text Available This paper mainly investigates the average consensus of multiagent systems with the problem of packet losses when both the first-order neighbors’ information and the second-order neighbors’ information are used. The problem is formulated under the sampled-data framework by discretizing the first-order agent dynamics with a zero-order hold. The communication graph is undirected and the loss of data across each communication link occurs at certain probability, which is governed by a Bernoulli process. It is found that the distributed average consensus speeds up by using the second-order neighbors’ information when packets are lost. Numerical examples are given to demonstrate the effectiveness of the proposed methods.

  2. Local average height distribution of fluctuating interfaces

    Science.gov (United States)

    Smith, Naftali R.; Meerson, Baruch; Sasorov, Pavel V.

    2017-01-01

    Height fluctuations of growing surfaces can be characterized by the probability distribution of height in a spatial point at a finite time. Recently there has been spectacular progress in the studies of this quantity for the Kardar-Parisi-Zhang (KPZ) equation in 1 +1 dimensions. Here we notice that, at or above a critical dimension, the finite-time one-point height distribution is ill defined in a broad class of linear surface growth models unless the model is regularized at small scales. The regularization via a system-dependent small-scale cutoff leads to a partial loss of universality. As a possible alternative, we introduce a local average height. For the linear models, the probability density of this quantity is well defined in any dimension. The weak-noise theory for these models yields the "optimal path" of the interface conditioned on a nonequilibrium fluctuation of the local average height. As an illustration, we consider the conserved Edwards-Wilkinson (EW) equation, where, without regularization, the finite-time one-point height distribution is ill defined in all physical dimensions. We also determine the optimal path of the interface in a closely related problem of the finite-time height-difference distribution for the nonconserved EW equation in 1 +1 dimension. Finally, we discuss a UV catastrophe in the finite-time one-point distribution of height in the (nonregularized) KPZ equation in 2 +1 dimensions.

  3. Consensus in averager-copier-voter networks of moving dynamical agents

    Science.gov (United States)

    Shang, Yilun

    2017-02-01

    This paper deals with a hybrid opinion dynamics comprising averager, copier, and voter agents, which ramble as random walkers on a spatial network. Agents exchange information following some deterministic and stochastic protocols if they reside at the same site in the same time. Based on stochastic stability of Markov chains, sufficient conditions guaranteeing consensus in the sense of almost sure convergence have been obtained. The ultimate consensus state is identified in the form of an ergodicity result. Simulation studies are performed to validate the effectiveness and availability of our theoretical results. The existence/non-existence of voters and the proportion of them are unveiled to play key roles during the consensus-reaching process.

  4. Asymptotic Time Averages and Frequency Distributions

    Directory of Open Access Journals (Sweden)

    Muhammad El-Taha

    2016-01-01

    Full Text Available Consider an arbitrary nonnegative deterministic process (in a stochastic setting {X(t,  t≥0} is a fixed realization, i.e., sample-path of the underlying stochastic process with state space S=(-∞,∞. Using a sample-path approach, we give necessary and sufficient conditions for the long-run time average of a measurable function of process to be equal to the expectation taken with respect to the same measurable function of its long-run frequency distribution. The results are further extended to allow unrestricted parameter (time space. Examples are provided to show that our condition is not superfluous and that it is weaker than uniform integrability. The case of discrete-time processes is also considered. The relationship to previously known sufficient conditions, usually given in stochastic settings, will also be discussed. Our approach is applied to regenerative processes and an extension of a well-known result is given. For researchers interested in sample-path analysis, our results will give them the choice to work with the time average of a process or its frequency distribution function and go back and forth between the two under a mild condition.

  5. Distributed Estimation using Bayesian Consensus Filtering

    Science.gov (United States)

    2014-06-06

    performance,” in 48th IEEE Conf. Decision Control, (Shanghai, China), pp. 7036–7042, December 2009. [18] M. H. DeGroot , Probability and Statistics...programming,” Autonomous Robots, vol. 16, pp. 49–79, January 2004. [24] M. H. DeGroot , “Reaching a consensus,” J. Amer. Statistical Assoc., vol. 69

  6. Distributed Consensus-Based Control of Multiple DC-Microgrids Clusters

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Dragicevic, Tomislav; Andrade, Fabio

    2014-01-01

    among the MGs. Using the consensus protocol, the global information can be accurately shared in a distributed way. This allows the power flow control to be achieved at the same time as it can be accomplished only at the cost of having the voltage differences inside the system. Similarly, a consensus......This paper presents consensus-based distributed control strategies for voltage regulation and power flow control of dc microgrid (MG) clusters. In the proposed strategy, primary level of control is used to regulate the common bus voltage inside each MG locally. An SOC-based adaptive droop method...... is introduced for this level which determines droop coefficient automatically, thus equalizing SOC of batteries inside each MG. In the secondary level, a distributed consensus based voltage control strategy is proposed to eliminate the average voltage deviation while guaranteeing proper regulation of power flow...

  7. Definitive Consensus for Distributed Data Inference

    OpenAIRE

    2011-01-01

    Inference from data is of key importance in many applications of informatics. The current trend in performing such a task of inference from data is to utilise machine learning algorithms. Moreover, in many applications that it is either required or is preferable to infer from the data in a distributed manner. Many practical difficulties arise from the fact that in many distributed applications we avert from transferring data or parts of it due to cost...

  8. Distributed static linear Gaussian models using consensus.

    Science.gov (United States)

    Belanovic, Pavle; Valcarcel Macua, Sergio; Zazo, Santiago

    2012-10-01

    Algorithms for distributed agreement are a powerful means for formulating distributed versions of existing centralized algorithms. We present a toolkit for this task and show how it can be used systematically to design fully distributed algorithms for static linear Gaussian models, including principal component analysis, factor analysis, and probabilistic principal component analysis. These algorithms do not rely on a fusion center, require only low-volume local (1-hop neighborhood) communications, and are thus efficient, scalable, and robust. We show how they are also guaranteed to asymptotically converge to the same solution as the corresponding existing centralized algorithms. Finally, we illustrate the functioning of our algorithms on two examples, and examine the inherent cost-performance trade-off.

  9. Distributed Particle Filter Implementation with Intermittent/Irregular Consensus Convergence

    CERN Document Server

    Mohammadi, Arash

    2011-01-01

    Motivated by non-linear, non-Gaussian, distributed multi-sensor/agent navigation and tracking applications, we propose a multi-rate consensus/fusion based framework for distributed implementation of the particle filter (CF/DPF). The CF/DPF framework is based on running localized particle filters to estimate the overall state vector at each observation node. Separate fusion filters are designed to consistently assimilate the local filtering distributions into the global posterior by compensating for the common past information between neighbouring nodes. The CF/DPF offers two distinct advantages over its counterparts. First, the CF/DPF framework is suitable for scenarios where network connectivity is intermittent and consensus can not be reached between two consecutive observations. Second, the CF/DPF is not limited to the Gaussian approximation for the global posterior density. A third contribution of the paper is the derivation of the optimal posterior Cram\\'er-Rao lower bound (PCRLB) for the distributed arc...

  10. Consensus+Innovations Distributed Kalman Filter With Optimized Gains

    Science.gov (United States)

    Das, Subhro; Moura, Jose M. F.

    2017-01-01

    In this paper, we address the distributed filtering and prediction of time-varying random fields represented by linear time-invariant (LTI) dynamical systems. The field is observed by a sparsely connected network of agents/sensors collaborating among themselves. We develop a Kalman filter type consensus+innovations distributed linear estimator of the dynamic field termed as Consensus+Innovations Kalman Filter. We analyze the convergence properties of this distributed estimator. We prove that the mean-squared error of the estimator asymptotically converges if the degree of instability of the field dynamics is within a pre-specified threshold defined as tracking capacity of the estimator. The tracking capacity is a function of the local observation models and the agent communication network. We design the optimal consensus and innovation gain matrices yielding distributed estimates with minimized mean-squared error. Through numerical evaluations, we show that, the distributed estimator with optimal gains converges faster and with approximately 3dB better mean-squared error performance than previous distributed estimators.

  11. Logical Consensus for Distributed and Robust Intrusion Detection

    CERN Document Server

    Fagiolini, Adriano

    2011-01-01

    In this paper we introduce a novel consensus mech- anism where agents of a network are able to share logical values, or Booleans, representing their local opinions on e.g. the presence of an intruder or of a fire within an indoor environment. We first formulate the logical consensus problem, and then we review relevant results in the literature on cellular automata and convergence of finite-state iteration maps. Under suitable joint conditions on the visibility of agents and their communication capability, we provide an algorithm for generating a logical linear consensus system that is globally stable. The solution is optimal in terms of the number of messages to be exchanged and the time needed to reach a consensus. Moreover, to cope with possible sensor failure, we propose a second design approach that produces robust logical nonlinear consensus systems tolerating a given maximum number of faults. Finally, we show applicability of the agreement mechanism to a case study consisting of a distributed Intrusion...

  12. Leader Election and Distributed Consensus with Quantum Resources

    CERN Document Server

    D'Hondt, E; Hondt, Ellie D'; Panangaden, Prakash

    2004-01-01

    In this paper we study paradigmatic tasks from classical distributed computing - leader election and distributed consensus - in the presence of quantum resources. Our main contribution is a demonstration of the special computational power of the W-state, and also of the GHZ-state. Several important results are brought forward. First, totally correct leader election is possible in anonymous quantum networks, which is in stark contrast with the classical situation. Next, we prove that the specific entanglement provided by the W- and GHZ-states, and their generalisations, is the only kind that exactly solves leader election and distributed consensus respectively. At the heart of the proofs of these impossibility results lie symmetry arguments.

  13. Analysis of Distributed Consensus Time Synchronization with Gaussian Delay over Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Gang Xiong

    2009-01-01

    Full Text Available This paper presents theoretical results on the convergence of the distributed consensus timing synchronization (DCTS algorithm for wireless sensor networks assuming general Gaussian delay between nodes. The asymptotic expectation and mean square of the global synchronization error are computed. The results lead to the definition of a time delay balanced network in which average timing consensus between nodes can be achieved despite random delays. Several structured network architectures are studied as examples, and their associated simulation results are used to validate analytical findings.

  14. Fastest Distribution Consensus Problem on Fusion of Two Star Networks

    CERN Document Server

    Jafarizadeh, Saber

    2010-01-01

    Finding optimal weights for the problem of Fastest Distributed Consensus on networks with different topologies has been an active area of research for a number of years. Here in this work we present an analytical solution for the problem of Fastest Distributed Consensus for a network formed from fusion of two different symmetric star networks or in other words a network consists of two different symmetric star networks which share the same central node. The solution procedure consists of stratification of associated connectivity graph of network and Semidefinite Programming (SDP), particularly solving the slackness conditions, where the optimal weights are obtained by inductive comparing of the characteristic polynomials initiated by slackness conditions. Some numerical simulations are carried out to investigate the trade-off between the parameters of two fused star networks, namely the length and number of branches.

  15. Combining experts' risk judgments on technology performance of phytoremediation: self-confidence ratings, averaging procedures, and formative consensus building.

    Science.gov (United States)

    Scholz, Roland W; Hansmann, Ralf

    2007-02-01

    Expert panels and averaging procedures are common means for coping with the uncertainty of effects of technology application in complex environments. We investigate the connection between confidence and the validity of expert judgment. Moreover, a formative consensus building procedure (FCB) is introduced that generates probability statements on the performance of technologies, and we compare different algorithms for the statistical aggregation of individual judgments. The case study refers to an expert panel of 10 environmental scientists assessing the performance of a soil cleanup technology that uses the capability of certain plants to accumulate heavy metals from the soil in the plant body (phytoremediation). The panel members first provided individual statements on the effectiveness of a phytoremediation. Such statements can support policymakers, answering the questions concerning the expected performance of the new technology in contaminated areas. The present study reviews (1) the steps of the FCB, (2) the constraints of technology application (contaminants, soil structure, etc.), (3) the measurement of expert knowledge, (4) the statistical averaging and the discursive agreement procedures, and (5) the boundaries of application for the FCB method. The quantitative statement oriented part of FCB generates terms such as: "The probability that the concentration of soil contamination will be reduced by at least 50% is 0.8." The data suggest that taking the median of the individual expert estimates provides the most accurate aggregated estimate. The discursive agreement procedure of FCB appears suitable for deriving politically relevant singular statements rather than for obtaining comprehensive information about uncertainties as represented by probability distributions.

  16. Fine tuning consensus optimization for distributed radio interferometric calibration

    CERN Document Server

    Yatawatta, Sarod

    2016-01-01

    We recently proposed the use of consensus optimization as a viable and effective way to improve the quality of calibration of radio interferometric data. We showed that it is possible to obtain far more accurate calibration solutions and also to distribute the compute load across a network of computers by using this technique. A crucial aspect in any consensus optimization problem is the selection of the penalty parameter used in the alternating direction method of multipliers (ADMM) iterations. This affects the convergence speed as well as the accuracy. In this paper, we use the Hessian of the cost function used in calibration to appropriately select this penalty. We extend our results to a multi-directional calibration setting, where we propose to use a penalty scaled by the squared intensity of each direction.

  17. Average of Distribution and Remarks on Box-Splines

    Institute of Scientific and Technical Information of China (English)

    LI Yue-sheng

    2001-01-01

    A class of generalized moving average operators is introduced, and the integral representations of an average function are provided. It has been shown that the average of Dirac δ-distribution is just the well known box-spline. Some remarks on box-splines, such as their smoothness and the corresponding partition of unity, are made. The factorization of average operators is derived. Then, the subdivision algorithm for efficient computing of box-splines and their linear combinations follows.

  18. Distributed Optimal Consensus Control for Multiagent Systems With Input Delay.

    Science.gov (United States)

    Zhang, Huaipin; Yue, Dong; Zhao, Wei; Hu, Songlin; Dou, Chunxia

    2017-06-27

    This paper addresses the problem of distributed optimal consensus control for a continuous-time heterogeneous linear multiagent system subject to time varying input delays. First, by discretization and model transformation, the continuous-time input-delayed system is converted into a discrete-time delay-free system. Two delicate performance index functions are defined for these two systems. It is shown that the performance index functions are equivalent and the optimal consensus control problem of the input-delayed system can be cast into that of the delay-free system. Second, by virtue of the Hamilton-Jacobi-Bellman (HJB) equations, an optimal control policy for each agent is designed based on the delay-free system and a novel value iteration algorithm is proposed to learn the solutions to the HJB equations online. The proposed adaptive dynamic programming algorithm is implemented on the basis of a critic-action neural network (NN) structure. Third, it is proved that local consensus errors of the two systems and weight estimation errors of the critic-action NNs are uniformly ultimately bounded while the approximated control policies converge to their target values. Finally, two simulation examples are presented to illustrate the effectiveness of the developed method.

  19. Distributed consensus with visual perception in multi-robot systems

    CERN Document Server

    Montijano, Eduardo

    2015-01-01

    This monograph introduces novel responses to the different problems that arise when multiple robots need to execute a task in cooperation, each robot in the team having a monocular camera as its primary input sensor. Its central proposition is that a consistent perception of the world is crucial for the good development of any multi-robot application. The text focuses on the high-level problem of cooperative perception by a multi-robot system: the idea that, depending on what each robot sees and its current situation, it will need to communicate these things to its fellows whenever possible to share what it has found and keep updated by them in its turn. However, in any realistic scenario, distributed solutions to this problem are not trivial and need to be addressed from as many angles as possible. Distributed Consensus with Visual Perception in Multi-Robot Systems covers a variety of related topics such as: ·         distributed consensus algorithms; ·         data association and robustne...

  20. Consensus-based distributed estimation in multi-agent systems with time delay

    Science.gov (United States)

    Abdelmawgoud, Ahmed

    During the last years, research in the field of cooperative control of swarm of robots, especially Unmanned Aerial Vehicles (UAV); have been improved due to the increase of UAV applications. The ability to track targets using UAVs has a wide range of applications not only civilian but also military as well. For civilian applications, UAVs can perform tasks including, but not limited to: map an unknown area, weather forecasting, land survey, and search and rescue missions. On the other hand, for military personnel, UAV can track and locate a variety of objects, including the movement of enemy vehicles. Consensus problems arise in a number of applications including coordination of UAVs, information processing in wireless sensor networks, and distributed multi-agent optimization. We consider a widely studied consensus algorithms for processing sensed data by different sensors in wireless sensor networks of dynamic agents. Every agent involved in the network forms a weighted average of its own estimated value of some state with the values received from its neighboring agents. We introduced a novelty of consensus-based distributed estimation algorithms. We propose a new algorithm to reach a consensus given time delay constraints. The proposed algorithm performance was observed in a scenario where a swarm of UAVs measuring the location of a ground maneuvering target. We assume that each UAV computes its state prediction and shares it with its neighbors only. However, the shared information applied to different agents with variant time delays. The entire group of UAVs must reach a consensus on target state. Different scenarios were also simulated to examine the effectiveness and performance in terms of overall estimation error, disagreement between delayed and non-delayed agents, and time to reach a consensus for each parameter contributing on the proposed algorithm.

  1. Distributed Weighted Parameter Averaging for SVM Training on Big Data

    OpenAIRE

    Das, Ayan; Bhattacharya, Sourangshu

    2015-01-01

    Two popular approaches for distributed training of SVMs on big data are parameter averaging and ADMM. Parameter averaging is efficient but suffers from loss of accuracy with increase in number of partitions, while ADMM in the feature space is accurate but suffers from slow convergence. In this paper, we report a hybrid approach called weighted parameter averaging (WPA), which optimizes the regularized hinge loss with respect to weights on parameters. The problem is shown to be same as solving...

  2. Exact Determination of Optimal Weights for Fastest Distributed Consensus Algorithm in Path Network via SDP

    CERN Document Server

    Jafarizadeh, Saber

    2010-01-01

    Providing an analytical solution for the problem of finding Fastest Distributed Consensus (FDC) is one of the challenging problems in the field of sensor networks. Most of the methods proposed so far deal with the FDC averaging algorithm problem by numerical convex optimization methods and in general no closed-form solution for finding FDC has been offered up to now except in [3] where the conjectured answer for path has been proved. Here in this work we present an analytical solution for the problem of Fastest Distributed Consensus for the Path network using semidefinite programming particularly solving the slackness conditions, where the optimal weights are obtained by inductive comparing of the characteristic polynomials initiated by slackness conditions.

  3. Implementing the distributed consensus-based estimation of environmental variables in unattended wireless sensor networks

    Science.gov (United States)

    Contreras, Rodrigo; Restrepo, Silvia E.; Pezoa, Jorge E.

    2014-10-01

    In this paper, the prototype implementation of a scalable, distributed protocol for calculating the global average of sensed environmental variables in unattended wireless sensor networks (WSNs) is presented. The design and implementation of the protocol introduces a communication scheme for discovering the WSN topology. Such scheme uses a synchronous flooding algorithm, which was implemented over an unreliable radiogram-based wireless channel. The topology discovery protocol has been synchronized with sampling time of the WSN and must be executed before the consensus-based estimation of the global averages. An average consensus algorithm, suited for clustered WSNs with static topologies, was selected from the literature. The algorithm was properly modified so that its implementation guarantees that the convergence time is bounded and less than the sampling time of the WSN. Moreover, to implement the consensus algorithm, a reliable packet-passing protocol was designed to exchange the weighting factors among the sensor nodes. Since the amount of data exchanged in each packet is bounded by the degree of the WSN, the scalability of the protocol is guaranteed to be linear. The proposed protocol was implemented in the Sun SPOT hardware/software platform using the Java programming language. All the radio communications were implemented over the IEEE 802.15.4 standard and the sensed environmental variables corresponded to the temperature and luminosity.

  4. Distribution of population-averaged observables in stochastic gene expression

    Science.gov (United States)

    Bhattacharyya, Bhaswati; Kalay, Ziya

    2014-01-01

    Observation of phenotypic diversity in a population of genetically identical cells is often linked to the stochastic nature of chemical reactions involved in gene regulatory networks. We investigate the distribution of population-averaged gene expression levels as a function of population, or sample, size for several stochastic gene expression models to find out to what extent population-averaged quantities reflect the underlying mechanism of gene expression. We consider three basic gene regulation networks corresponding to transcription with and without gene state switching and translation. Using analytical expressions for the probability generating function of observables and large deviation theory, we calculate the distribution and first two moments of the population-averaged mRNA and protein levels as a function of model parameters, population size, and number of measurements contained in a data set. We validate our results using stochastic simulations also report exact results on the asymptotic properties of population averages which show qualitative differences among different models.

  5. Distribution of population averaged observables in stochastic gene expression

    Science.gov (United States)

    Bhattacharyya, Bhaswati; Kalay, Ziya

    2014-03-01

    Observation of phenotypic diversity in a population of genetically identical cells is often linked to the stochastic nature of chemical reactions involved in gene regulatory networks. We investigate the distribution of population averaged gene expression levels as a function of population, or sample size for several stochastic gene expression models to find out to what extent population averaged quantities reflect the underlying mechanism of gene expression. We consider three basic gene regulation networks corresponding to transcription with and without gene state switching and translation. Using analytical expressions for the probability generating function (pgf) of observables and Large Deviation Theory, we calculate the distribution of population averaged mRNA and protein levels as a function of model parameters and population size. We validate our results using stochastic simulations also report exact results on the asymptotic properties of population averages which show qualitative differences for different models. We calculate the skewness and coefficient of variance for pgfs to estimate the sample size required for population average that contains information about gene expression models. This is relevant to experiments where a large number of data points are unavailable.

  6. Sensor Networks with Random Links: Topology Design for Distributed Consensus

    CERN Document Server

    Kar, Soummya

    2007-01-01

    In a sensor network, in practice, the communication among sensors is subject to:(1) errors or failures at random times; (3) costs; and(2) constraints since sensors and networks operate under scarce resources, such as power, data rate, or communication. The signal-to-noise ratio (SNR) is usually a main factor in determining the probability of error (or of communication failure) in a link. These probabilities are then a proxy for the SNR under which the links operate. The paper studies the problem of designing the topology, i.e., assigning the probabilities of reliable communication among sensors (or of link failures) to maximize the rate of convergence of average consensus, when the link communication costs are taken into account, and there is an overall communication budget constraint. To consider this problem, we address a number of preliminary issues: (1) model the network as a random topology; (2) establish necessary and sufficient conditions for mean square sense (mss) and almost sure (a.s.) convergence o...

  7. Distributed Consensus over Wireless Sensor Networks Affected by Multipath Fading

    CERN Document Server

    Scutari, Gesualdo

    2008-01-01

    The design of sensor networks capable of reaching a consensus on a globally optimal decision test, without the need for a fusion center, is a problem that has received considerable attention in the last years. Many consensus algorithms have been proposed, with convergence conditions depending on the graph describing the interaction among the nodes. In most works, the graph is undirected and there are no propagation delays. Only recently, the analysis has been extended to consensus algorithms incorporating propagation delays. In this work, we propose a consensus algorithm able to converge to a globally optimal decision statistic, using a wideband wireless network, governed by a fairly simple MAC mechanism, where each link is a multipath, frequency-selective, channel. The main contribution of the paper is to derive necessary and sufficient conditions on the network topology and sufficient conditions on the channel transfer functions guaranteeing the exponential convergence of the consensus algorithm to a global...

  8. Distributed Consensus Algorithms in Sensor Networks: Link Failures and Channel Noise

    CERN Document Server

    Kar, Soummya

    2007-01-01

    We study average consensus when, simultaneously, the topology is random (links are offline or online at random times) and the communication among sensors is corrupted by additive noise. Additive noise causes the states of the standard average consensus algorithm to diverge. To overcome this, we consider two modifications to average consensus: \\begin{inparaenum}[1)] \\item the $\\mathcal{A-ND}$ algorithm with weights decaying to zero (slowly, satisfying a persistence condition); and \\item the $\\mathcal{A-NC}$ algorithm with time invariant weights but that averages successive runs, restarted with the same initial conditions. \\end{inparaenum} To study the behavior of these two algorithms under the simultaneous random link failures and additive noise, we use controlled Markov processes and stochastic approximation results. With respect to the $\\mathcal{A-ND}$ algorithm, we show that the states reach a.s. consensus to a finite random variable, whose variance can be made arbitrarily small, and the expected value of t...

  9. Belief Consensus Algorithms for Distributed Target Tracking in Wireless Sensor Networks

    CERN Document Server

    Savic, Vladimir; Zazo, Santiago

    2012-01-01

    In distributed target tracking in wireless sensor networks (WSN), agreement on the target state is usually achieved by the construction and maintenance of a communication path. Such an approach lack robustness to failures, and is not applicable to asynchronous networks. Recently, methods have been proposed that can solve these problems using consensus algorithms. However, these methods suffer from at least one of the following problems: i) they do not use fastest consensus methods, and ii) they cannot handle all parametric and nonparametric likelihood functions. In this paper, we propose a general framework for target tracking using distributed particle filtering (DPF) based on three asynchronous belief consensus (BC) algorithms: standard belief consensus (SBC), broadcast gossip (BG), and belief propagation (BP). Since DPF can be also solved (without consensus) by exchanging the observed data, we determine under which conditions BC-based methods are preferred. Finally, we perform extensive simulations to anal...

  10. Fault-Tolerant Consensus of Multi-Agent System With Distributed Adaptive Protocol.

    Science.gov (United States)

    Chen, Shun; Ho, Daniel W C; Li, Lulu; Liu, Ming

    2015-10-01

    In this paper, fault-tolerant consensus in multi-agent system using distributed adaptive protocol is investigated. Firstly, distributed adaptive online updating strategies for some parameters are proposed based on local information of the network structure. Then, under the online updating parameters, a distributed adaptive protocol is developed to compensate the fault effects and the uncertainty effects in the leaderless multi-agent system. Based on the local state information of neighboring agents, a distributed updating protocol gain is developed which leads to a fully distributed continuous adaptive fault-tolerant consensus protocol design for the leaderless multi-agent system. Furthermore, a distributed fault-tolerant leader-follower consensus protocol for multi-agent system is constructed by the proposed adaptive method. Finally, a simulation example is given to illustrate the effectiveness of the theoretical analysis.

  11. A PD-Like Protocol With a Time Delay to Average Consensus Control for Multi-Agent Systems Under an Arbitrarily Fast Switching Topology.

    Science.gov (United States)

    Wang, Dong; Zhang, Ning; Wang, Jianliang; Wang, Wei

    2016-03-08

    This paper is concerned with the problem of average consensus control for multi-agent systems with linear and Lipschitz nonlinear dynamics under a switching topology. First, a proportional and derivative-like consensus algorithm for linear cases with a time delay is designed to address such a problem. By a system transformation, such a problem is converted to the stability problem of a switched delay system. The stability analysis is performed based on a proposed Lyapunov-Krasoversusii functional including a triple-integral term and sufficient conditions are obtained to guarantee the average consensus for multi-agent systems under arbitrary switching. Second, extensions to the Lipschitz nonlinear cases are further presented. Finally, numerical examples are given to illustrate the effectiveness of the results.

  12. On Distributed Reduced-Order Observer-Based Protocol for Linear Multiagent Consensus under Switching Topology

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2013-01-01

    Full Text Available We discuss linear multiagent systems consensus problem with distributed reduced-order observer-based protocol under switching topology. We use Jordan decomposition method to prove that the proposed protocols can solve consensus problem under directed fixed topology. By constructing a parameter-dependent common Lyapunov function, we prove that the distributed reduced-order observer-based protocol can also solve the continuous-time multi-agent consensus problem under the undirected switching interconnection topology. Then, we investigate the leader-following consensus problem and propose a reduced-order observer-based protocol for each following agent. By using similar analysis method, we can prove that all following agents can track the leader under a class of directed interaction topologies. Finally, the given simulation example also shows the effectiveness of our obtained result.

  13. Distributed consensus tracking for multiple uncertain nonlinear strict-feedback systems under a directed graph.

    Science.gov (United States)

    Yoo, Sung Jin

    2013-04-01

    In this brief, we study the distributed consensus tracking control problem for multiple strict-feedback systems with unknown nonlinearities under a directed graph topology. It is assumed that the leader's output is time-varying and has been accessed by only a small fraction of followers in a group. The distributed dynamic surface design approach is proposed to design local consensus controllers in order to guarantee the consensus tracking between the followers and the leader. The function approximation technique using neural networks is employed to compensate unknown nonlinear terms induced from the controller design procedure. From the Lyapunov stability theorem, it is shown that the consensus errors are cooperatively semiglobally uniformly ultimately bounded and converge to an adjustable neighborhood of the origin.

  14. Distributed Robust H∞ Consensus Control of Multiagent Systems with Communication Errors Using Dynamic Output Feedback Protocol

    Directory of Open Access Journals (Sweden)

    Xi Yang

    2013-01-01

    Full Text Available This paper studies robust consensus problem for multiagent systems modeled by an identical linear time-invariant system under a fixed communication topology. Communication errors in the transferred data are considered, and only the relative output information between each agent and its neighbors is available. A distributed dynamic output feedback protocol is proposed, and sufficient conditions for reaching consensus with a prescribed H∞ performance are presented. Numerical examples are given to illustrate the theoretical results.

  15. Dynamic Consensus Algorithm based Distributed Unbalance Compensation in Islanded Microgrids

    DEFF Research Database (Denmark)

    Meng, Lexuan; Zhao, Xin; Firoozabadi, Mehdi Savaghebi;

    2015-01-01

    In islanded microgrids (MG), distributed generators (DG) can be employed as distributed compensators for improving the power quality (voltage unbalance and harmonics) in consumer side. Hierarchical control is usually applied with different control levels differentiated. In case of voltage unbalance...... compensation, droop control and virtual impedance can be applied in primary control to help the positive sequence active and reactive power sharing. Secondary control is used to assist voltage unbalance compensation. However, if transmission line differences are considered, the negative sequence current cannot...

  16. Distributed Position-Based Consensus of Second-Order Multiagent Systems With Continuous/Intermittent Communication.

    Science.gov (United States)

    Song, Qiang; Liu, Fang; Wen, Guanghui; Cao, Jinde; Yang, Xinsong

    2017-04-24

    This paper considers the position-based consensus in a network of agents with double-integrator dynamics and directed topology. Two types of distributed observer algorithms are proposed to solve the consensus problem by utilizing continuous and intermittent position measurements, respectively, where each observer does not interact with any other observers. For the case of continuous communication between network agents, some convergence conditions are derived for reaching consensus in the network with a single constant delay or multiple time-varying delays on the basis of the eigenvalue analysis and the descriptor method. When the network agents can only obtain intermittent position data from local neighbors at discrete time instants, the consensus in the network without time delay or with nonuniform delays is investigated by using the Wirtinger's inequality and the delayed-input approach. Numerical examples are given to illustrate the theoretical analysis.

  17. Distributed Node-to-Node Consensus of Multiagent Systems with Delayed Nonlinear Dynamics and Intermittent Communications

    Directory of Open Access Journals (Sweden)

    Kexin Jia

    2015-01-01

    Full Text Available The paper is concerned with the problem of distributed node-to-node consensus of multiagent systems with delayed nonlinear dynamics and communication constraints. A new kind of consensus protocol based only on the intermittent measurements of neighboring agents is proposed to make each follower track the corresponding leader asymptotically. Based on the Lyapunov stability theory and M-matrix theory, some novel and simple criteria are derived for node-to-node consensus of multiagent systems. It is shown that consensus can be reached if the communication time duration is larger than the corresponding threshold value. Finally, a numerical example is provided to demonstrate the effectiveness of the obtained theoretical results.

  18. Beyond average temperature: distribution of wintering birds at multiple scales

    OpenAIRE

    Villén Pérez, Sara

    2013-01-01

    Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Ecología. Fecha de lectura: 03-12-2013 To disentangle the subtleties of the relationship between the thermal environment and the distribution of wintering birds, at multiple spatial scales. Specifically, to analyze the relative influence of temperature on species distributions, its interaction with various thermal and non-thermal factors, and the context-dependence of these relationships...

  19. Distributed consensus-based formation control for multiple nonholonomic mobile robots with a specified reference trajectory

    Science.gov (United States)

    Peng, Zhaoxia; Wen, Guoguang; Rahmani, Ahmed; Yu, Yongguang

    2015-06-01

    In this paper, the distributed formation control problem for multiple nonholonomic mobile robots using consensus-based approach is considered. A transformation is given to convert the formation control problem for multiple nonholonomic mobile robots into a state consensus problem. Distributed control laws are developed for achieving the formation control objectives: a group of nonholonomic mobile robots at least exponentially converge to a desired geometric pattern with its centroid moving along the specified reference trajectory. Rigorous proofs are provided by using graph, matrix , and Lyapunov theories. Simulations are also given to verify the effectiveness of the theoretical results.

  20. Distributed Consensus-Based Robust Adaptive Formation Control for Nonholonomic Mobile Robots with Partial Known Dynamics

    Directory of Open Access Journals (Sweden)

    Zhaoxia Peng

    2014-01-01

    Full Text Available This paper investigates the distributed consensus-based robust adaptive formation control for nonholonomic mobile robots with partially known dynamics. Firstly, multirobot formation control problem has been converted into a state consensus problem. Secondly, the practical control strategies, which incorporate the distributed kinematic controllers and the robust adaptive torque controllers, are designed for solving the formation control problem. Thirdly, the specified reference trajectory for the geometric centroid of the formation is assumed as the trajectory of a virtual leader, whose information is available to only a subset of the followers. Finally, numerical results are provided to illustrate the effectiveness of the proposed control approaches.

  1. Distributed consensus on minimum time rendezvous via cyclic alternating projection

    OpenAIRE

    Hu, Chunhe; Chen, Zongji

    2014-01-01

    In this paper, we propose a distributed algorithm to solve planar minimum time multi-vehicle rendezvous problem with non-identical velocity constraints on cyclic digraph (topology). Motivated by the cyclic alternating projection method that can compute a point's projection on the intersection of some convex sets, we transform the minimum time rendezvous problem into finding the distance between the position plane and the intersection of several second-order cones in position-time space. The d...

  2. Adaptive Consensus of Distributed Varying Scale Wireless Sensor Networks under Tolerable Jamming Attacks

    Directory of Open Access Journals (Sweden)

    Jinping Mou

    2013-01-01

    Full Text Available Consensus problem is investigated for a varying scale wireless sensor network (VSWSN under tolerable jamming attacks, where the scale of the network is increasing or decreasing due to the newly joined nodes or the removed nodes, respectively; the tolerable jamming attack means that the attack strength is limited. It supposes that during the communications, all nodes may encounter with the tolerable jamming attacks; when the attack power is larger than the given value, the attacked nodes fall asleep, or otherwise the nodes are awakened. Under the sleep method, based on the Lyapunov method, it shows that if the communicating graph is the global limited intersectional connection (GLI connection and the system has the enough dwell time in the intersectional topology, then under the designed consensus protocol, all nodes achieve the global average consensus.

  3. On Consensus of Multiple High-order Uncertain Systems Based on Distributed Backstepping Framework

    Directory of Open Access Journals (Sweden)

    Jie Huang

    2014-08-01

    Full Text Available This paper focuses on the consensus problem of multiple high-order systems with uncertainties. Since it is difficult to use matrix theory approaches to design consensus controllers for a class of multiple high-order uncertain nonlinear systems, in this paper a set of consensus control laws are proposed by employing adaptive control theory and a backstepping technique. The distributed virtual control functions of the multi-agent systems are elaborately constructed by only using their local information in the recursive controller design procedure. Furthermore, the asymptotic stability of the overall interconnected system is proved relying on the Lyapunov stability analysis method. Finally, simulations are provided to verify the effectiveness of the control algorithms.

  4. Distributed leader-following finite-time consensus control for linear multiagent systems under switching topology.

    Science.gov (United States)

    Xu, Xiaole; Chen, Shengyong; Gao, Lixin

    2014-01-01

    This paper investigates the finite-time consensus problem of leader-following multiagent systems. The dynamical models for all following agents and the leader are assumed the same general form of linear system, and the interconnection topology among the agents is assumed to be switching and undirected. We mostly consider the continuous-time case. By assuming that the states of neighbouring agents are known to each agent, a sufficient condition is established for finite-time consensus via a neighbor-based state feedback protocol. While the states of neighbouring agents cannot be available and only the outputs of neighbouring agents can be accessed, the distributed observer-based consensus protocol is proposed for each following agent. A sufficient condition is provided in terms of linear matrix inequalities to design the observer-based consensus protocol, which makes the multiagent systems achieve finite-time consensus under switching topologies. Then, we discuss the counterparts for discrete-time case. Finally, we provide an illustrative example to show the effectiveness of the design approach.

  5. Distributed Leader-Following Finite-Time Consensus Control for Linear Multiagent Systems under Switching Topology

    Directory of Open Access Journals (Sweden)

    Xiaole Xu

    2014-01-01

    Full Text Available This paper investigates the finite-time consensus problem of leader-following multiagent systems. The dynamical models for all following agents and the leader are assumed the same general form of linear system, and the interconnection topology among the agents is assumed to be switching and undirected. We mostly consider the continuous-time case. By assuming that the states of neighbouring agents are known to each agent, a sufficient condition is established for finite-time consensus via a neighbor-based state feedback protocol. While the states of neighbouring agents cannot be available and only the outputs of neighbouring agents can be accessed, the distributed observer-based consensus protocol is proposed for each following agent. A sufficient condition is provided in terms of linear matrix inequalities to design the observer-based consensus protocol, which makes the multiagent systems achieve finite-time consensus under switching topologies. Then, we discuss the counterparts for discrete-time case. Finally, we provide an illustrative example to show the effectiveness of the design approach.

  6. Exact Determination of Optimal Weights for Fastest Distribution Consensus Algorithm in Star and CCS Networks via SDP

    CERN Document Server

    Jafarizadeh, Saber

    2010-01-01

    Providing an analytical solution for the problem of finding Fastest Distributed Consensus (FDC) is one of the challenging problems in the field of sensor networks. Most of the methods proposed so far deal with the FDC averaging algorithm problem by numerical methods, with convex-optimization techniques and in general no closed-form solution for finding FDC has been offered up to now except in [1] where the conjectured answer for path has been proved. Here in this work we present the analytical solution for the problem of finding FDC by means of semidefinite programming (SDP), for two networks, Star and Complete Cored Star which are containing path as a particular case. Our method in this paper is based on convexity of fastest distributed consensus averaging problem, and we rather allow the networks to have their own symmetric pattern, in order to find the optimal weights. The main idea of the proposed methodology is to solve the slackness conditions to obtain a closed-form expression for the optimal weights, ...

  7. Decentralized Observer with a Consensus Filter for Distributed Discrete-Time Linear Systems

    Science.gov (United States)

    Acikmese, Behcet; Mandic, Milan

    2011-01-01

    This paper presents a decentralized observer with a consensus filter for the state observation of a discrete-time linear distributed systems. In this setup, each agent in the distributed system has an observer with a model of the plant that utilizes the set of locally available measurements, which may not make the full plant state detectable. This lack of detectability is overcome by utilizing a consensus filter that blends the state estimate of each agent with its neighbors' estimates. We assume that the communication graph is connected for all times as well as the sensing graph. It is proven that the state estimates of the proposed observer asymptotically converge to the actual plant states under arbitrarily changing, but connected, communication and sensing topologies. As a byproduct of this research, we also obtained a result on the location of eigenvalues, the spectrum, of the Laplacian for a family of graphs with self-loops.

  8. Distributed Consensus of Stochastic Delayed Multi-agent Systems Under Asynchronous Switching.

    Science.gov (United States)

    Wu, Xiaotai; Tang, Yang; Cao, Jinde; Zhang, Wenbing

    2016-08-01

    In this paper, the distributed exponential consensus of stochastic delayed multi-agent systems with nonlinear dynamics is investigated under asynchronous switching. The asynchronous switching considered here is to account for the time of identifying the active modes of multi-agent systems. After receipt of confirmation of mode's switching, the matched controller can be applied, which means that the switching time of the matched controller in each node usually lags behind that of system switching. In order to handle the coexistence of switched signals and stochastic disturbances, a comparison principle of stochastic switched delayed systems is first proved. By means of this extended comparison principle, several easy to verified conditions for the existence of an asynchronously switched distributed controller are derived such that stochastic delayed multi-agent systems with asynchronous switching and nonlinear dynamics can achieve global exponential consensus. Two examples are given to illustrate the effectiveness of the proposed method.

  9. Distributed Consensus Tracking for Second-Order Nonlinear Multiagent Systems with a Specified Reference State

    Directory of Open Access Journals (Sweden)

    Guoguang Wen

    2014-01-01

    Full Text Available This paper mainly addresses the distributed consensus tracking problem for second-order nonlinear multiagent systems with a specified reference trajectory. The dynamics of each follower consists of two terms: nonlinear inherent dynamics and a simple communication protocol relying only on the position and velocity information of its neighbors. The consensus reference is taken as a virtual leader, whose output is only its position and velocity information that is available to only a subset of a group of followers. To achieve consensus tracking, a class of nonsmooth control protocols is proposed which reply on the relative information among the neighboring agents. Then some corresponding sufficient conditions are derived. It is shown that if the communication graph associated with the virtual leader and followers is connected at each time instant, the consensus can be achieved at least globally exponentially with the proposed protocol. Rigorous proofs are given by using graph theory, matrix theory, and Lyapunov theory. Finally, numerical examples are presented to illustrate the theoretical analysis.

  10. Vibration suppression of distributed parameter flexible structures by Integral Consensus Control

    Science.gov (United States)

    Omidi, Ehsan; Mahmoodi, S. Nima

    2016-03-01

    Integral Consensus Control (ICC) is proposed and implemented in this paper for the first time, as a novel approach for vibration control in distributed parameter flexible structures. The ICC consists of multiple parallel first-order lossy integrators, with the goal of targeting all major participating resonant modes in the oscillation of the structure. The vibration control design is taken to a different level, by integrating the concept of consensus control design into the new dynamics. Each control patch on the flexible structure is considered as a node of a network, and a communication topology with consensus control terms are augmented in the controller design dynamics. The result is an effective vibration controller, which is also robust to failures and inconsistencies in the control system. A cantilever is used as a sample flexible structure to investigate the control method. Multi-agent representation of the system, state estimator dynamics and the ICC model are designed for the structure. Extensive numerical simulations have been conducted to show the suppression performance of the ICC under different input disturbances. A comparative study is presented to show the advantage of the decentralized design over the conventional centralized approach. The new consensus control design provides new possibilities to vibration control problems, where an effective, robust and synchronized suppression is needed.

  11. A Multiagent-based Consensus Algorithm for Distributed Coordinated Control of Distributed Generators in the Energy Internet

    DEFF Research Database (Denmark)

    Sun, Qiuye; Han, Renke; Zhang, Huaguang

    2015-01-01

    which is applied to distributed generators in the Energy Internet. Then, the decomposed tasks, models, and information flow of the proposed method are analyzed. The proposed coordinated controller installed between the Energy Internet and the Main-Grid keeps voltage angles and amplitudes consensus while......With the bidirectional power flow provided by the Energy Internet, various methods are promoted to improve and increase the energy utilization between Energy Internet and Main-Grid. This paper proposes a novel distributed coordinated controller combined with a multi-agent-based consensus algorithm...... providing accurate power-sharing and minimizing circulating currents. Finally, the Energy Internet can be integrated into the Main-Grid seamlessly if necessary. Hence the Energy Internet can be operated as a spinning reserve system. Simulation results are provided to show the effectiveness of the proposed...

  12. Using of rank distributions in the study of perennial changes for monthly average temperatures

    Science.gov (United States)

    Nemirovskiy, V. B.; Stoyanov, A. K.; Tartakovsky, V. A.

    2015-11-01

    The possibility of comparing the climatic data of various years with using rank distributions is considered in this paper. As a climatic data, the annual variation of temperature on the spatial areas of meteorological observations with high variability in average temperatures is considered. The results of clustering of the monthly average temperatures values by means of a recurrent neural network were used as the basis of comparing. For a given space of weather observations the rank distribution of the clusters cardinality identified for each year of observation, is being constructed. The resulting rank distributions allow you to compare the spatial temperature distributions of various years. An experimental comparison for rank distributions of the annual variation of monthly average temperatures has confirmed the presence of scatter for various years, associated with different spatio-temporal distribution of temperature. An experimental comparison of rank distributions revealed a difference in the integral annual variation of monthly average temperatures of various years for the Northern Hemisphere.

  13. Second-Order Consensus in Multiagent Systems via Distributed Sliding Mode Control.

    Science.gov (United States)

    Yu, Wenwu; Wang, He; Cheng, Fei; Yu, Xinghuo; Wen, Guanghui

    2016-11-22

    In this paper, the new decoupled distributed sliding-mode control (DSMC) is first proposed for second-order consensus in multiagent systems, which finally solves the fundamental unknown problem for sliding-mode control (SMC) design of coupled networked systems. A distributed full-order sliding-mode surface is designed based on the homogeneity with dilation for reaching second-order consensus in multiagent systems, under which the sliding-mode states are decoupled. Then, the SMC is applied to the decoupled sliding-mode states to reach their origin in finite time, which is the sliding-mode surface. The states of agents can first reach the designed sliding-mode surface in finite time and then move to the second-order consensus state along the surface in finite time as well. The DSMC designed in this paper can eliminate the influence of singularity problems and weaken the influence of chattering, which is still very difficult in the SMC systems. In addition, DSMC proposes a general decoupling framework for designing SMC in networked multiagent systems. Simulations are presented to verify the theoretical results in this paper.

  14. Reaching an Optimal Consensus: Distributed Intersection Computation for Multi-agent Systems

    CERN Document Server

    Shi, Guodong; Hong, Yiguang

    2011-01-01

    In this paper, multi-agent systems minimizing a sum of objective functions, where each component is only known to a particular node, is considered for continuous-time dynamics with time-varying interconnection topologies. Assuming that each node can observe a convex solution set of its optimization component, and the intersection of all such sets is nonempty, the considered optimization problem is converted to an intersection computation problem. By a simple distributed control rule, the considered multi-agent system achieves not only a consensus, but also an optimal one by agreeing within the optimal solution set of the group's optimization objective. Directed and bidirectional communications are studied respectively, and connectivity conditions are given to ensure a global optimal consensus. In this way, the corresponding intersection computation problem is solved by the proposed decentralized continuous-time algorithm. We establish several important properties of the distance functions with respect to the ...

  15. Pull-Based Distributed Event-Triggered Consensus for Multiagent Systems With Directed Topologies.

    Science.gov (United States)

    Yi, Xinlei; Lu, Wenlian; Chen, Tianping

    2017-01-01

    This paper mainly investigates consensus problem with a pull-based event-triggered feedback control. For each agent, the diffusion coupling feedbacks are based on the states of its in-neighbors at its latest triggering time, and the next triggering time of this agent is determined by its in-neighbors' information. The general directed topologies, including irreducible and reducible cases, are investigated. The scenario of distributed continuous communication is considered first. It is proved that if the network topology has a spanning tree, then the event-triggered coupling algorithm can realize the consensus for the multiagent system. Then, the results are extended to discontinuous communication, i.e., self-triggered control, where each agent computes its next triggering time in advance without having to observe the system's states continuously. The effectiveness of the theoretical results is illustrated by a numerical example finally.

  16. Consensus of Linear Multi-Agent Systems by Distributed Event-Triggered Strategy.

    Science.gov (United States)

    Hu, Wenfeng; Liu, Lu; Feng, Gang

    2016-01-01

    This paper studies the consensus problem of multi-agent systems with general linear dynamics. We propose a novel event-triggered control scheme with some desirable features, namely, distributed, asynchronous, and independent. It is shown that consensus of the controlled multi-agent system can be reached asymptotically. The feasibility of the event-triggered strategy is further verified by the exclusion of both singular triggering and Zeno behavior. Moreover, a self-triggered algorithm is developed, where the next triggering time instant for each agent is determined based on its local information at the previous triggering time instant. Continuous monitoring of measurement errors is thus avoided. The effectiveness of the proposed control schemes is demonstrated by two examples.

  17. A Secure Scheme for Distributed Consensus Estimation against Data Falsification in Heterogeneous Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Shichao Mi

    2016-02-01

    Full Text Available Heterogeneous wireless sensor networks (HWSNs can achieve more tasks and prolong the network lifetime. However, they are vulnerable to attacks from the environment or malicious nodes. This paper is concerned with the issues of a consensus secure scheme in HWSNs consisting of two types of sensor nodes. Sensor nodes (SNs have more computation power, while relay nodes (RNs with low power can only transmit information for sensor nodes. To address the security issues of distributed estimation in HWSNs, we apply the heterogeneity of responsibilities between the two types of sensors and then propose a parameter adjusted-based consensus scheme (PACS to mitigate the effect of the malicious node. Finally, the convergence property is proven to be guaranteed, and the simulation results validate the effectiveness and efficiency of PACS.

  18. A Secure Scheme for Distributed Consensus Estimation against Data Falsification in Heterogeneous Wireless Sensor Networks.

    Science.gov (United States)

    Mi, Shichao; Han, Hui; Chen, Cailian; Yan, Jian; Guan, Xinping

    2016-02-19

    Heterogeneous wireless sensor networks (HWSNs) can achieve more tasks and prolong the network lifetime. However, they are vulnerable to attacks from the environment or malicious nodes. This paper is concerned with the issues of a consensus secure scheme in HWSNs consisting of two types of sensor nodes. Sensor nodes (SNs) have more computation power, while relay nodes (RNs) with low power can only transmit information for sensor nodes. To address the security issues of distributed estimation in HWSNs, we apply the heterogeneity of responsibilities between the two types of sensors and then propose a parameter adjusted-based consensus scheme (PACS) to mitigate the effect of the malicious node. Finally, the convergence property is proven to be guaranteed, and the simulation results validate the effectiveness and efficiency of PACS.

  19. Dynamic Consensus Algorithm based Distributed Voltage Harmonic Compensation in Islanded Microgrids

    DEFF Research Database (Denmark)

    Meng, Lexuan; Tang, Fen; Firoozabadi, Mehdi Savaghebi

    2015-01-01

    In islanded microgrids, the existence of nonlinear electric loads may cause voltage distortion and affect the performance of power quality sensitive equipment. Thanks to the prevalent utilization of interfacing power electronic devices and information/communication technologies, distributed...... generators can be employed as compensators to enhance the power quality on consumer side. However, conventional centralized control is facing obstacles because of the distributed fashion of generation and consumption. Accordingly, this paper proposes a consensus algorithm based distributed hierarchical...... control to realize voltage harmonic compensation and accurate current sharing in multi-bus islanded microgrids. Low order harmonic components are considered as examples in this paper. Harmonic current sharing is also realized among distributed generators by applying the proposed methods. Plug...

  20. Dynamic Consensus Algorithm Based Distributed Global Efficiency Optimization of a Droop Controlled DC Microgrid

    DEFF Research Database (Denmark)

    Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.

    2014-01-01

    . Accordingly, this paper proposes a dynamic consensus algorithm based distributed optimization method aiming at improving the system efficiency while offering higher expandability and flexibility when compared to centralized control. Hardware-in-the-loop (HIL) results are shown to demonstrate the effectiveness......In a DC microgrid, several paralleled conversion systems are installed in distributed substations for transferring power from external grid to a DC microgrid. Droop control is used for the distributed load sharing among all the DC/DC converters. Considering the typical efficiency feature of power...... electronic converters, optimization method can be implemented in tertiary level for improving the overall system efficiency. However, optimization purposes usually require centralized communication, data acquisition and computation which might be either impractical or costly for dispersed systems...

  1. Q D$-Learning: A Collaborative Distributed Strategy for Multi-Agent Reinforcement Learning Through Consensus + Innovations

    Science.gov (United States)

    Kar, Soummya; Moura, José M. F.; Poor, H. Vincent

    2013-04-01

    The paper considers a class of multi-agent Markov decision processes (MDPs), in which the network agents respond differently (as manifested by the instantaneous one-stage random costs) to a global controlled state and the control actions of a remote controller. The paper investigates a distributed reinforcement learning setup with no prior information on the global state transition and local agent cost statistics. Specifically, with the agents' objective consisting of minimizing a network-averaged infinite horizon discounted cost, the paper proposes a distributed version of $Q$-learning, $\\mathcal{QD}$-learning, in which the network agents collaborate by means of local processing and mutual information exchange over a sparse (possibly stochastic) communication network to achieve the network goal. Under the assumption that each agent is only aware of its local online cost data and the inter-agent communication network is \\emph{weakly} connected, the proposed distributed scheme is almost surely (a.s.) shown to yield asymptotically the desired value function and the optimal stationary control policy at each network agent. The analytical techniques developed in the paper to address the mixed time-scale stochastic dynamics of the \\emph{consensus + innovations} form, which arise as a result of the proposed interactive distributed scheme, are of independent interest.

  2. Multiagent-based Distributed Control for Operation Cost Minimization of Droop Controlled DC Microgrid Using Incremental Cost Consensus

    DEFF Research Database (Denmark)

    Li, Chendan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2015-01-01

    In this paper, a multiagent based distributed control is proposed for DC microgrid to minimize the operation cost. The power of each distributed generator (DG) is dispatched in a distributed manner in a multiagent system by means of voltage scheduling. Every DG unit is taken as an agent......, and they share the load corresponding to the operation cost of all the units in the system with only communication with direct neighbors through incremental cost consensus. The power regulation according to the power reference generated by consensus is implemented through voltage scheduling in local primary...

  3. Average projection type weighted Cramér-von Mises statistics for testing some distributions

    Institute of Scientific and Technical Information of China (English)

    CUI; Hengjian(崔恒建)

    2002-01-01

    This paper addresses the problem of testing goodness-of-fit for several important multivariate distributions: (Ⅰ) Uniform distribution on p-dimensional unit sphere; (Ⅱ) multivariate standard normal distribution; and (Ⅲ) multivariate normal distribution with unknown mean vector and covariance matrix. The average projection type weighted Cramér-yon Mises test statistic as well as estimated and weighted Cramér-von Mises statistics for testing distributions (Ⅰ), (Ⅱ) and (Ⅲ) are constructed via integrating projection direction on the unit sphere, and the asymptotic distributions and the expansions of those test statistics under the null hypothesis are also obtained. Furthermore, the approach of this paper can be applied to testing goodness-of-fit for elliptically contoured distributions.

  4. Distributed Consensus Optimization in Multiagent Networks With Time-Varying Directed Topologies and Quantized Communication.

    Science.gov (United States)

    Li, Huaqing; Huang, Chicheng; Chen, Guo; Liao, Xiaofeng; Huang, Tingwen

    2017-03-31

    This paper considers solving a class of optimization problems which are modeled as the sum of all agents' convex cost functions and each agent is only accessible to its individual function. Communication between agents in multiagent networks is assumed to be limited: each agent can only interact information with its neighbors by using time-varying communication channels with limited capacities. A technique which overcomes the limitation is to implement a quantization process to the interacted information. The quantized information is first encoded as a binary sequence at the side of each agent before sending. After the binary sequence is received by the neighboring agent, corresponding decoding scheme is utilized to resume the original information with a certain degree of error which is caused by the quantization process. With the availability of each agent's encoding states (associated with its out-channels) and decoding states (associated with its in-channels), we devise a set of distributed optimization algorithms that generate two iterative sequences, one of which converges to the optimal solution and the other of which reaches to the optimal value. We prove that if the parameters satisfy some mild conditions, the quantization errors are bounded and the consensus optimization can be achieved. How to minimize the number of quantization level of each connected communication channel in fixed networks is also explored thoroughly. It is found that, by properly choosing system parameters, one bit information exchange suffices to ensure consensus optimization. Finally, we present two numerical simulation experiments to illustrate the efficacy of the algorithms as well as to validate the theoretical findings.

  5. Average capacity for optical wireless communication systems over exponentiated Weibull distribution non-Kolmogorov turbulent channels.

    Science.gov (United States)

    Cheng, Mingjian; Zhang, Yixin; Gao, Jie; Wang, Fei; Zhao, Fengsheng

    2014-06-20

    We model the average channel capacity of optical wireless communication systems for cases of weak to strong turbulence channels, using the exponentiation Weibull distribution model. The joint effects of the beam wander and spread, pointing errors, atmospheric attenuation, and the spectral index of non-Kolmogorov turbulence on system performance are included. Our results show that the average capacity decreases steeply as the propagation length L changes from 0 to 200 m and decreases slowly down or tends to a stable value as the propagation length L is greater than 200 m. In the weak turbulence region, by increasing the detection aperture, we can improve the average channel capacity and the atmospheric visibility as an important issue affecting the average channel capacity. In the strong turbulence region, the increase of the radius of the detection aperture cannot reduce the effects of the atmospheric turbulence on the average channel capacity, and the effect of atmospheric visibility on the channel information capacity can be ignored. The effect of the spectral power exponent on the average channel capacity in the strong turbulence region is higher than weak turbulence region. Irrespective of the details determining the turbulent channel, we can say that pointing errors have a significant effect on the average channel capacity of optical wireless communication systems in turbulence channels.

  6. DISTRIBUTION OF RIVER RUNOFF AND ITS CLIMATE FACTORS IN AVERAGE AND EXTREME YEARS

    Directory of Open Access Journals (Sweden)

    Vladimir Konovalov

    2011-01-01

    Full Text Available Schematic maps of spatial distribution of seasonal precipitation amounts and average air temperatures were obtained for the areas studied in years with normal and extreme values of annual river runoff. Data on precipitation for January–December (I–XII and on average air temperatures for June–September (VI–IX during 1961–1990 collected at 93 meteorological stations located along 30.20°–44.08°N and 67.20°–82.98°E, altitude 122–4 169 m above sea level, were used in the maps’ compilation. For each point-element (i.e. a meteorological station with proper data, the ordinates of an integral empirical function of distribution of probabilities P were calculated from these data for a 30-year sample period and for each year were received average values and standard deviations of P. In characteristic years were revealed, significant differences of spatial distribution of climatic factors and runoff. It was found out also that the spatial distribution of the total volume of glaciers melting is less variable in the years with extreme water yields compared to the average years. This peculiarity is very beneficial for hydropower and agriculture sectors because it provides additional natural ability to stabilize water balance of reservoirs. Piecewise multi-factor linear equations were obtained to calculate the statistical probability of glaciers’ total melting in low and high flow years as a function of geographical coordinates and the average altitude of firn boundary.

  7. Average Distribution of Ionic Charges and Ionizability for the Au Plasma System

    Institute of Scientific and Technical Information of China (English)

    杨天丽; 蒋刚; 朱正和

    2002-01-01

    Using relativistic multi-configuration Dirac-Fock theory, we calculate the transition data of 3dj - n fj, (n =5, 6, 7) for the M-shell from an Ni-like Au ion to an As-like Auion using the GRASP programme with the core-polarization, quantum electrodynamical effect and Breit correction. Based on the present calculation results andthe experiment of the Xingguang-Ⅱ laser facilities, the average distribution of ionic charge and the ionizabilityhave been derived. The average ionization degree of Au plasma Z* is 49.06 ± 0.5, which is comparable with theresult of the Lawrence Livermore National Laboratory.

  8. Containment and Consensus-based Distributed Coordination Control for Voltage Bound and Reactive Power Sharing in AC Microgrid

    DEFF Research Database (Denmark)

    Han, Renke; Meng, Lexuan; Ferrari-Trecate, Giancarlo

    2017-01-01

    This paper offers a highly flexible and reliable control strategy to achieve voltage bounded regulation and accurate reactive power sharing coordinately in AC Micro-Grids. A containment and consensus-based distributed coordination controller is proposed, by which each output voltage magnitude can...

  9. Debate over a Proposed FedEx Distribution Hub: Examining the Role of Consensus, Power and Norms of Communication Ethics.

    Science.gov (United States)

    Thompson, Kathleen B.

    This paper examines an ongoing community debate over a proposed FedEx distribution hub to be constructed at the local airport. The essay looks to theorists, including Patsy Healey, Richard Johannesen, Daniel Kemmis, James Klumpp, and Martha Nussbaum. These theorists provide a way to view the role of consensus, power, and norms of communication…

  10. Containment and Consensus-based Distributed Coordination Control for Voltage Bound and Reactive Power Sharing in AC Microgrid

    DEFF Research Database (Denmark)

    Han, Renke; Meng, Lexuan; Ferrari-Trecate, Giancarlo

    2017-01-01

    This paper offers a highly flexible and reliable control strategy to achieve voltage bounded regulation and accurate reactive power sharing coordinately in AC Micro-Grids. A containment and consensus-based distributed coordination controller is proposed, by which each output voltage magnitude can...

  11. Output Consensus of Heterogeneous Linear Multi-Agent Systems by Distributed Event-Triggered/Self-Triggered Strategy.

    Science.gov (United States)

    Hu, Wenfeng; Liu, Lu; Feng, Gang

    2016-09-02

    This paper addresses the output consensus problem of heterogeneous linear multi-agent systems. We first propose a novel distributed event-triggered control scheme. It is shown that, with the proposed control scheme, the output consensus problem can be solved if two matrix equations are satisfied. Then, we further propose a novel self-triggered control scheme, with which continuous monitoring is avoided. By introducing a fixed timer into both event- and self-triggered control schemes, Zeno behavior can be ruled out for each agent. The effectiveness of the event- and self-triggered control schemes is illustrated by an example.

  12. Typical versus averaged overlap distribution in spin glasses: Evidence for droplet scaling theory

    Science.gov (United States)

    Monthus, Cécile; Garel, Thomas

    2013-10-01

    We consider the statistical properties over disordered samples (J) of the overlap distribution PJ(q) which plays the role of an order parameter in spin glasses. We show that near zero temperature (i) the typical overlap distribution is exponentially small in the central region of -1models in which the notion of length does not exist); (ii) the rescaled variable v=-[lnPJ(q)]/Nθ remains an O(1) random positive variable describing sample-to-sample fluctuations; (iii) the averaged distribution PJ(q)¯ is nontypical and dominated by rare anomalous samples. Similar statements hold for the cumulative overlap distribution IJ(q0)≡∫0q0dqPJ(q). These results are derived explicitly for the spherical mean-field model with θ=1/3, ϕ(q)=1-q2, and the random variable v corresponds to the rescaled difference between the two largest eigenvalues of Gaussian orthogonal ensemble random matrices. Then we compare numerically the typical and averaged overlap distributions for the long-ranged one-dimensional Ising spin glass with random couplings decaying as J(r)∝r-σ for various values of the exponent σ, corresponding to various droplet exponents θ(σ), and for the mean-field Sherrington-Kirkpatrick model (corresponding formally to the σ=0 limit of the previous model). Our conclusion is that future studies on spin glasses should measure the typical values of the overlap distribution Ptyp(q) or of the cumulative overlap distribution Ityp(q0)=elnIJ(q0)¯ to obtain clearer conclusions on the nature of the spin-glass phase.

  13. $QD$-Learning: A Collaborative Distributed Strategy for Multi-Agent Reinforcement Learning Through Consensus + Innovations

    CERN Document Server

    Kar, Soummya; Poor, H Vincent

    2012-01-01

    The paper considers a class of multi-agent Markov decision processes (MDPs), in which the network agents respond differently (as manifested by the instantaneous one-stage random costs) to a global controlled state and the control actions of a remote controller. The paper investigates a distributed reinforcement learning setup with no prior information on the global state transition and local agent cost statistics. Specifically, with the agents' objective consisting of minimizing a network-averaged infinite horizon discounted cost, the paper proposes a distributed version of $Q$-learning, $\\mathcal{QD}$-learning, in which the network agents collaborate by means of local processing and mutual information exchange over a sparse (possibly stochastic) communication network to achieve the network goal. Under the assumption that each agent is only aware of its local online cost data and the inter-agent communication network is \\emph{weakly} connected, the proposed distributed scheme is almost surely (a.s.) shown to ...

  14. General Ripple Mobility Model: A Novel Mobility Model of Uniform Spatial Distribution and Diverse Average Speed

    Science.gov (United States)

    Chen, Chun-Hung; Wu, Ho-Ting; Ke, Kai-Wei

    Simulations are often deployed to evaluate proposed mechanisms or algorithms in Mobile Ad Hoc Networks (MANET). In MANET, the impacts of some simulation parameters are noticeable, such as transmission range, data rate etc. However, the effect of mobility model is not clear until recently. Random Waypoint (RWP) is one of the most applied nodal mobility models in many simulations due to its clear procedures and easy employments. However, it exhibits the two major problems: decaying average speed and border effect. Both problems will overestimate the performance of the employed protocols and applications. Although many recently proposed mobility models are able to reduce or eliminate the above-mentioned problems, the concept of Diverse Average Speed (DAS) has not been introduced. DAS aims to provide different average speeds within the same speed range. In most mobility models, the average speed is decided when the minimum and maximum speeds are set. In this paper, we propose a novel mobility model, named General Ripple Mobility Model (GRMM). GRMM targets to provide a uniform nodal spatial distribution and DAS without decaying average speed. The simulations and analytic results have demonstrated the merits of the outstanding properties of the GRMM model.

  15. Distributed Consensus of Nonlinear Multi-Agent Systems on State-Controlled Switching Topologies

    Directory of Open Access Journals (Sweden)

    Kairui Chen

    2016-01-01

    Full Text Available This paper considers the consensus problem of nonlinear multi-agent systems under switching directed topologies. Specifically, the dynamics of each agent incorporates an intrinsic nonlinear term and the interaction topology may not contain a spanning tree at any time. By designing a state-controlled switching law, we show that the multi-agent system with the neighbor-based protocol can achieve consensus if the switching topologies jointly contain a spanning tree. Moreover, an easily manageable algebraic criterion is deduced to unravel the underlying mechanisms in reaching consensus. Finally, a numerical example is exploited to illustrate the effectiveness of the developed theoretical results.

  16. Distributed MPC based consensus for single-integrator multi-agent systems.

    Science.gov (United States)

    Cheng, Zhaomeng; Fan, Ming-Can; Zhang, Hai-Tao

    2015-09-01

    This paper addresses model predictive control schemes for consensus in multi-agent systems (MASs) with discrete-time single-integrator dynamics under switching directed interaction graphs. The control horizon is extended to be greater than one which endows the closed-loop system with extra degree of freedom. We derive sufficient conditions on the sampling period and the interaction graph to achieve consensus by using the property of infinite products of stochastic matrices. Consensus can be achieved asymptotically if the sampling period is selected such that the interaction graph among agents has a directed spanning tree jointly. Significantly, if the interaction graph always has a spanning tree, one can select an arbitrary large sampling period to guarantee consensus. Finally, several simulations are conducted to illustrate the effectiveness of the theoretical results.

  17. Distributed robust finite-time nonlinear consensus protocols for multi-agent systems

    Science.gov (United States)

    Zuo, Zongyu; Tie, Lin

    2016-04-01

    This paper investigates the robust finite-time consensus problem of multi-agent systems in networks with undirected topology. Global nonlinear consensus protocols augmented with a variable structure are constructed with the aid of Lyapunov functions for each single-integrator agent dynamics in the presence of external disturbances. In particular, it is shown that the finite settling time of the proposed general framework for robust consensus design is upper bounded for any initial condition. This makes it possible for network consensus problems to design and estimate the convergence time offline for a multi-agent team with a given undirected information flow. Finally, simulation results are presented to demonstrate the performance and effectiveness of our finite-time protocols.

  18. Study of distribution and characteristics of the time average of pressure of a water cushion pool

    Science.gov (United States)

    Guo, Y. H.; Fu, J. F.

    2016-08-01

    When a dam discharges flood water, the plunging flow with greater kinetic energy, will scour the riverbed, resulting in erosion damage. In order to improve the anti-erosion capacity of a riverbed, the cushion pool created. This paper is based on turbulent jet theoryto deduce the semi-empirical formula of the time average of pressure in the impinging portion of the cushion pool. Additionally, MATLAB numerical is used to conduct a simulation analysis according to turbulent jet energy and watercushion depth when water floods into the water cushion pool, to determine the regularities of distribution and related characteristics.

  19. Percentiles of the run-length distribution of the Exponentially Weighted Moving Average (EWMA) median chart

    Science.gov (United States)

    Tan, K. L.; Chong, Z. L.; Khoo, M. B. C.; Teoh, W. L.; Teh, S. Y.

    2017-09-01

    Quality control is crucial in a wide variety of fields, as it can help to satisfy customers’ needs and requirements by enhancing and improving the products and services to a superior quality level. The EWMA median chart was proposed as a useful alternative to the EWMA \\bar{X} chart because the median-type chart is robust against contamination, outliers or small deviation from the normality assumption compared to the traditional \\bar{X}-type chart. To provide a complete understanding of the run-length distribution, the percentiles of the run-length distribution should be investigated rather than depending solely on the average run length (ARL) performance measure. This is because interpretation depending on the ARL alone can be misleading, as the process mean shifts change according to the skewness and shape of the run-length distribution, varying from almost symmetric when the magnitude of the mean shift is large, to highly right-skewed when the process is in-control (IC) or slightly out-of-control (OOC). Before computing the percentiles of the run-length distribution, optimal parameters of the EWMA median chart will be obtained by minimizing the OOC ARL, while retaining the IC ARL at a desired value.

  20. Minimal-Approximation-Based Distributed Consensus Tracking of a Class of Uncertain Nonlinear Multiagent Systems With Unknown Control Directions.

    Science.gov (United States)

    Choi, Yun Ho; Yoo, Sung Jin

    2017-03-28

    A minimal-approximation-based distributed adaptive consensus tracking approach is presented for strict-feedback multiagent systems with unknown heterogeneous nonlinearities and control directions under a directed network. Existing approximation-based consensus results for uncertain nonlinear multiagent systems in lower-triangular form have used multiple function approximators in each local controller to approximate unmatched nonlinearities of each follower. Thus, as the follower's order increases, the number of the approximators used in its local controller increases. However, the proposed approach employs only one function approximator to construct the local controller of each follower regardless of the order of the follower. The recursive design methodology using a new error transformation is derived for the proposed minimal-approximation-based design. Furthermore, a bounding lemma on parameters of Nussbaum functions is presented to handle the unknown control direction problem in the minimal-approximation-based distributed consensus tracking framework and the stability of the overall closed-loop system is rigorously analyzed in the Lyapunov sense.

  1. Subnational distribution of average farm size and smallholder contributions to global food production

    Science.gov (United States)

    Samberg, Leah H.; Gerber, James S.; Ramankutty, Navin; Herrero, Mario; West, Paul C.

    2016-12-01

    Smallholder farming is the most prevalent form of agriculture in the world, supports many of the planet’s most vulnerable populations, and coexists with some of its most diverse and threatened landscapes. However, there is little information about the location of small farms, making it difficult both to estimate their numbers and to implement effective agricultural, development, and land use policies. Here, we present a map of mean agricultural area, classified by the amount of land per farming household, at subnational resolutions across three key global regions using a novel integration of household microdata and agricultural landscape data. This approach provides a subnational estimate of the number, average size, and contribution of farms across much of the developing world. By our estimates, 918 subnational units in 83 countries in Latin America, sub-Saharan Africa, and South and East Asia average less than five hectares of agricultural land per farming household. These smallholder-dominated systems are home to more than 380 million farming households, make up roughly 30% of the agricultural land and produce more than 70% of the food calories produced in these regions, and are responsible for more than half of the food calories produced globally, as well as more than half of global production of several major food crops. Smallholder systems in these three regions direct a greater percentage of calories produced toward direct human consumption, with 70% of calories produced in these units consumed as food, compared to 55% globally. Our approach provides the ability to disaggregate farming populations from non-farming populations, providing a more accurate picture of farming households on the landscape than has previously been available. These data meet a critical need, as improved understanding of the prevalence and distribution of smallholder farming is essential for effective policy development for food security, poverty reduction, and conservation agendas.

  2. Average Spatial Distribution of Cosmic Rays behind the Interplanetary Shock—Global Muon Detector Network Observations

    Science.gov (United States)

    Kozai, M.; Munakata, K.; Kato, C.; Kuwabara, T.; Rockenbach, M.; Dal Lago, A.; Schuch, N. J.; Braga, C. R.; Mendonça, R. R. S.; Jassar, H. K. Al; Sharma, M. M.; Duldig, M. L.; Humble, J. E.; Evenson, P.; Sabbah, I.; Tokumaru, M.

    2016-07-01

    We analyze the galactic cosmic ray (GCR) density and its spatial gradient in Forbush Decreases (FDs) observed with the Global Muon Detector Network (GMDN) and neutron monitors (NMs). By superposing the GCR density and density gradient observed in FDs following 45 interplanetary shocks (IP-shocks), each associated with an identified eruption on the Sun, we infer the average spatial distribution of GCRs behind IP-shocks. We find two distinct modulations of GCR density in FDs, one in the magnetic sheath and the other in the coronal mass ejection (CME) behind the sheath. The density modulation in the sheath is dominant in the western flank of the shock, while the modulation in the CME ejecta stands out in the eastern flank. This east-west asymmetry is more prominent in GMDN data responding to ˜60 GV GCRs than in NM data responding to ˜10 GV GCRs, because of the softer rigidity spectrum of the modulation in the CME ejecta than in the sheath. The geocentric solar ecliptic-y component of the density gradient, G y , shows a negative (positive) enhancement in FDs caused by the eastern (western) eruptions, while G z shows a negative (positive) enhancement in FDs caused by the northern (southern) eruptions. This implies that the GCR density minimum is located behind the central flank of IP-shocks and propagating radially outward from the location of the solar eruption. We also confirmed that the average G z changes its sign above and below the heliospheric current sheet, in accord with the prediction of the drift model for the large-scale GCR transport in the heliosphere.

  3. Average spatial distribution of cosmic rays behind the interplanetary shock -Global Muon Detector Network observations-

    CERN Document Server

    Kozai, M; Kato, C; Kuwabara, T; Rockenbach, M; Lago, A Dal; Schuch, N J; Braga, C R; Mendonça, R R S; Jassar, H K Al; Sharma, M M; Duldig, M L; Humble, J E; Evenson, P; Sabbah, I; Tokumaru, M

    2016-01-01

    We analyze the galactic cosmic ray (GCR) density and its spatial gradient in Forbush Decreases (FDs) observed with the Global Muon Detector Network (GMDN) and neutron monitors (NMs). By superposing the GCR density and density gradient observed in FDs following 45 interplanetary shocks (IP-shocks), each associated with an identified eruption on the sun, we infer the average spatial distribution of GCRs behind IP-shocks. We find two distinct modulations of GCR density in FDs, one in the magnetic sheath and the other in the coronal mass ejection (CME) behind the sheath. The density modulation in the sheath is dominant in the western flank of the shock, while the modulation in the CME ejecta stands out in the eastern flank. This east-west asymmetry is more prominent in GMDN data responding to $\\sim$ 60 GV GCRs than in NM data responding to $\\sim$ 10 GV GCRs, because of softer rigidity spectrum of the modulation in the CME ejecta than in the sheath. The GSE-y component of the density gradient, $G_y$ shows a negati...

  4. Multiagent based Distributed Control for Operation Cost Minimization of Droop Controlled AC Microgrid Using Incremental Cost Consensus

    DEFF Research Database (Denmark)

    Li, Chendan; Firoozabadi, Mehdi Savaghebi; Quintero, Juan Carlos Vasquez

    2015-01-01

    Microgrid, as a promising technology to integrate renewable energy resources in the distribution system, is gaining increasing research interests recently. Although many previous works have been done based on the droop control in a microgrid, they mainly focus on achieving proportional power...... sharing based on the power rating. With various types of distributed generator (DG) units in the system, factors that closely related to the operation cost, such as fuel cost and efficiencies of the generator should be taken into account in order to improve the efficiency of the whole system....... In this paper, a multiagent based distributed method is proposed to minimize operation cost of the AC microgrid. Each DG is acting as an agent which regulates the power individually using proposed frequency scheduling method. Optimal power command is obtained through carefully designed consensus algorithm...

  5. Distributed H∞ Filtering with Consensus Strategies in Sensor Networks: Considering Consensus Tracking Error%传感器网络中带有一致性策略的分布式H∞。滤波:考虑一致性跟踪误差

    Institute of Scientific and Technical Information of China (English)

    WAN Yi-Ming; DONG Wei; YE Hao

    2012-01-01

    The existing distributed H∞ filtering with consensus strategies consists of two steps:the consensus step through locally communicating with neighboring sensor nodes and the local filtering step.In this paper,the influence of consensus tracking error on the local estimation error is analyzed,and a distributed H∞ filtering algorithm considering the consensus tracking error is proposed.When the number of consensus iterations per sampling period is limited,the proposed method can suppress the effect of consensus tracking error on local estimation error; when the number of consensus iterations per sampling period goes to infinity,i.e.,the consensus tracking error converges to zero,the local filtering in the distributed algorithm reduces to the centralized H∞ filtering.Simulation shows the effectiveness of the proposed method.

  6. Distributed adaptive output consensus control of second-order systems containing unknown non-linear control gains

    Science.gov (United States)

    Wang, Gang; Wang, Chaoli; Du, Qinghui; Cai, Xuan

    2016-10-01

    In this paper, we address the output consensus problem of tracking a desired trajectory for a group of second-order agents on a directed graph with a fixed topology. Each agent is modelled by a second-order non-linear system with unknown non-linear dynamics and unknown non-linear control gains. Only a subset of the agents is given access to the desired trajectory information directly. A distributed adaptive consensus protocol driving all agents to track the desired trajectory is presented using the backstepping technique and approximation technique of Fourier series (FSs). The FS structure is taken not only for tracking the non-linear dynamics but also the unknown portion in the controller design procedure, which can avoid virtual controllers containing the uncertain terms. Stability analysis and parameter convergence of the proposed algorithm are conducted based on the Lyapunov theory and the algebraic graph theory. It is also demonstrated that arbitrary small tracking errors can be achieved by appropriately choosing design parameters. Though the proposed work is applicable for second-order non-linear systems containing unknown non-linear control gains, the proposed controller design can be easily extended to higher-order non-linear systems containing unknown non-linear control gains. Simulation results show the effectiveness of the proposed schemes.

  7. SPATIAL DISTRIBUTION OF THE AVERAGE RUNOFF IN THE IZA AND VIȘEU WATERSHEDS

    Directory of Open Access Journals (Sweden)

    HORVÁTH CS.

    2015-03-01

    Full Text Available The average runoff represents the main parameter with which one can best evaluate an area’s water resources and it is also an important characteristic in al river runoff research. In this paper we choose a GIS methodology for assessing the spatial evolution of the average runoff, using validity curves we identifies three validity areas in which the runoff changes differently with altitude. The tree curves were charted using the average runoff values of 16 hydrometric stations from the area, eight in the Vișeu and eight in the Iza river catchment. Identifying the appropriate areas of the obtained correlations curves (between specific average runoff and catchments mean altitude allowed the assessment of potential runoff at catchment level and on altitudinal intervals. By integrating the curves functions in to GIS we created an average runoff map for the area; from which one can easily extract runoff data using GIS spatial analyst functions. The study shows that from the three areas the highest runoff corresponds with the third zone but because it’s small area the water volume is also minor. It is also shown that with the use of the created runoff map we can compute relatively quickly correct runoff values for areas without hydrologic control.

  8. Distributed Voltage Unbalance Compensation in Islanded Microgrids by Using Dynamic-Consensus-Algorithm

    DEFF Research Database (Denmark)

    Meng, Lexuan; Zhao, Xin; Tang, Fen;

    2016-01-01

    In islanded microgrids (MGs), distributed generators (DGs) can be employed as distributed compensators for improving the power quality in the consumer side. Two-level hierarchical control can be used for voltage unbalance compensation. Primary level, consisting of droop control and virtual...... impedance, can be applied to help the positive sequence active and reactive power sharing. Secondary level is used to assist voltage unbalance compensation. However, if distribution line differences are considered, the negative sequence current cannot be well shared among DGs. In order to overcome...

  9. Going Beyond Average Joe's Happiness : Using Quantile Regressions to Analyze the Full Subjective Well-Being Distribution

    OpenAIRE

    Binder, Martin; Coad, Alex

    2010-01-01

    Standard regression techniques are only able to give an incomplete picture of the relationship between subjective well-being and its determinants since the very idea of conventional estimators such as OLS is the averaging out over the whole distribution: studies based on such regression techniques thus are implicitly only interested in Average Joe's happiness. Using cross-sectional data from the British Household Panel Survey (BHPS) for the year 2006, we apply quantile regressions to analyze ...

  10. Secondary Frequency and Voltage Control of Islanded Microgrids via Distributed Averaging

    DEFF Research Database (Denmark)

    W. Simpson-Porco, John; Shafiee, Qobad; Dorfler, Florian

    2015-01-01

    actions. The frequency controller rapidly regulates the microgrid frequency to its nominal value while maintaining active power sharing among the distributed generators. Tuning of the voltage controller provides a simple and intuitive trade-off between the conflicting goals of voltage regulation......In this work we present new distributed controllers for secondary frequency and voltage control in islanded microgrids. Inspired by techniques from cooperative control, the proposed controllers use localized information and nearest neighbour communication to collectively perform secondary control...... and reactive power sharing. Our designs require no knowledge of the microgrid topology, impedances or loads. The distributed architecture allows for flexibility and redundancy, and eliminates the need for a central microgrid controller. We provide a voltage stability analysis and present extensive experimental...

  11. Average Behavior of Battery - Electric Vehicles for Distributed Energy System Studies

    DEFF Research Database (Denmark)

    Marra, Francesco; Træholt, Chresten; Larsen, Esben

    2010-01-01

    The increase of focus on electric vehicles (EVs) as distributed energy resources calls for new concepts of aggregated models of batteries. Despite the developed battery models for EVs applications, when looking at energy storage scenarios using EVs, both geographical-temporal aspects and battery...

  12. Dependence of the population on the temperature in the Boltzmann distribution: a simple relation involving the average energy

    NARCIS (Netherlands)

    Angeli, C.; Cimiraglia, R.; Dallo, F.; Guareschi, R.; Tenti, L.

    2013-01-01

    The dependence on the temperature of the population of the ith state, Pi, in the Boltzmann distribution is analyzed by studying its derivative with respect to the temperature, T. A simple expression is found, involving Pi, the energy of the state, Ei, and the average energy, âŸ̈E⟩. This relation

  13. Dependence of the population on the temperature in the Boltzmann distribution: a simple relation involving the average energy

    NARCIS (Netherlands)

    Angeli, C.; Cimiraglia, R.; Dallo, F.; Guareschi, R.; Tenti, L.

    2013-01-01

    The dependence on the temperature of the population of the ith state, Pi, in the Boltzmann distribution is analyzed by studying its derivative with respect to the temperature, T. A simple expression is found, involving Pi, the energy of the state, Ei, and the average energy, âŸ̈E⟩. This relation i

  14. Parton distributions at low x and gluon- and quark average multiplicities

    CERN Document Server

    Kotikov, Anatoly

    2015-01-01

    We shown the general approach for Q2 evolution of parton densities and fragmentation functions at low x based on the diagonalization. The diagonalization leads to the two components in the Q2 evolution, each of which contains a nonperturbative parameter. The values of the parameters can be found by fits of the experimental data for the deep-inelastic scattering structure function F2 and for average jet multiplicities. One of the components contains the all large logarithms ln(1/x) and produce the basic contribution at small x region. The second one is regular at low x but its contribution is very important to have a good agreement with experimental data

  15. Recovery of the histogram of hourly ozone distribution from weekly average concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Olcese, Luis E. [Departamento de Fisico Quimica/INFIQC, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, 5000 Cordoba (Argentina)]. E-mail: lolcese@fcq.unc.edu.ar; Toselli, Beatriz M. [Departamento de Fisico Quimica/INFIQC, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, 5000 Cordoba (Argentina)

    2006-05-15

    A simple method is presented for estimating hourly distribution of air pollutants, based on data collected by passive sensors on a weekly or bi-weekly basis with no need for previous measurements at a site. In order for this method to be applied to locations where no hourly records are available, reference data from other sites are required to generate calibration histograms. The proposed procedure allows one to obtain the histogram of hourly ozone values during a given week with an error of about 30%, which is good considering the simplicity of this approach. This method can be a valuable tool for sites that lack previous hourly records of pollutant ambient concentrations, where it can be used to verify compliance with regulations or to estimate the AOT40 index with an acceptable degree of exactitude. - The histogram of hourly ozone distribution can be obtained based on passive sensor data.

  16. A Recursive Multiscale Correlation-Averaging Algorithm for an Automated Distributed Road Condition Monitoring System

    Energy Technology Data Exchange (ETDEWEB)

    Ndoye, Mandoye [Lawrence Livermore National Laboratory (LLNL); Barker, Alan M [ORNL; Krogmeier, James [Purdue University; Bullock, Darcy [Purdue University

    2011-01-01

    A signal processing approach is proposed to jointly filter and fuse spatially indexed measurements captured from many vehicles. It is assumed that these measurements are influenced by both sensor noise and measurement indexing uncertainties. Measurements from low-cost vehicle-mounted sensors (e.g., accelerometers and Global Positioning System (GPS) receivers) are properly combined to produce higher quality road roughness data for cost-effective road surface condition monitoring. The proposed algorithms are recursively implemented and thus require only moderate computational power and memory space. These algorithms are important for future road management systems, which will use on-road vehicles as a distributed network of sensing probes gathering spatially indexed measurements for condition monitoring, in addition to other applications, such as environmental sensing and/or traffic monitoring. Our method and the related signal processing algorithms have been successfully tested using field data.

  17. Recovery of the histogram of hourly ozone distribution from weekly average concentrations.

    Science.gov (United States)

    Olcese, Luis E; Toselli, Beatriz M

    2006-05-01

    A simple method is presented for estimating hourly distribution of air pollutants, based on data collected by passive sensors on a weekly or bi-weekly basis with no need for previous measurements at a site. In order for this method to be applied to locations where no hourly records are available, reference data from other sites are required to generate calibration histograms. The proposed procedure allows one to obtain the histogram of hourly ozone values during a given week with an error of about 30%, which is good considering the simplicity of this approach. This method can be a valuable tool for sites that lack previous hourly records of pollutant ambient concentrations, where it can be used to verify compliance with regulations or to estimate the AOT40 index with an acceptable degree of exactitude.

  18. Consensus-based distributed cooperative learning from closed-loop neural control systems.

    Science.gov (United States)

    Chen, Weisheng; Hua, Shaoyong; Zhang, Huaguang

    2015-02-01

    In this paper, the neural tracking problem is addressed for a group of uncertain nonlinear systems where the system structures are identical but the reference signals are different. This paper focuses on studying the learning capability of neural networks (NNs) during the control process. First, we propose a novel control scheme called distributed cooperative learning (DCL) control scheme, by establishing the communication topology among adaptive laws of NN weights to share their learned knowledge online. It is further proved that if the communication topology is undirected and connected, all estimated weights of NNs can converge to small neighborhoods around their optimal values over a domain consisting of the union of all state orbits. Second, as a corollary it is shown that the conclusion on the deterministic learning still holds in the decentralized adaptive neural control scheme where, however, the estimated weights of NNs just converge to small neighborhoods of the optimal values along their own state orbits. Thus, the learned controllers obtained by DCL scheme have the better generalization capability than ones obtained by decentralized learning method. A simulation example is provided to verify the effectiveness and advantages of the control schemes proposed in this paper.

  19. AVERAGE GEOMETRICAL FEATURES OF THE ELECTRON WAVE PACKAGES DISTRIBUTION IN METALLIC CONDUCTORS WITH PULSED AXIAL CURRENT OF HIGH DENSITY

    Directory of Open Access Journals (Sweden)

    M. I. Baranov

    2016-11-01

    Full Text Available Purpose. Calculation and experimental determination of average geometrical features of distributing of macroscopic electron wave packages (EWP in round cylindrical metallic conductors with the pulsed axial current of high density. Methodology. Theoretical bases of the electrical engineering, bases of atomic and quantum physics, electrophysics bases of technique of high voltage and high pulsed currents. Results. The results of the conducted calculation and experimental researches are resulted on close determination of average geometrical features of distribution of longitudinal and radial EWP of macroscopic sizes in the indicated conductors. These descriptions are included by the average widths of «hot» and «cold» longitudinal and radial areas of conductor, and also average steps of division into the periods of similar areas. Results of the executed calculations and high temperature experiments for average geometrical features of longitudinal EWP in the zincked steel wire of diameter of 1.6 mm and length of 320 mm with the aperiodic impulse of current of temporal form 9 ms/160 ms and by amplitude 745 A coincide within the limits of 19 %. Originality. First with the use of methods of atomic and quantum physics the features of the stochastic distributing and mean values of basic geometrical sizes are analysed macroscopic longitudinal and radial EWP in round cylindrical metallic conductors with the pulsed axial current of high density. Practical value. Drawing on the got results in practice will allow more reliably to forecast geometrical sizes and places of localization of arising up in the probed metallic conductors with pulsed axial current of high density longitudinal and radial EWP.

  20. Giant dipole resonance in 88Mo from phonon damping model strength functions averaged over temperature and angular momentum distributions

    Science.gov (United States)

    Dinh Dang, N.; Ciemala, M.; Kmiecik, M.; Maj, A.

    2013-05-01

    The line shapes of giant dipole resonance (GDR) in the decay of the compound nucleus 88Mo, which is formed after the fusion-evaporation reaction 48Ti + 40Ca at various excitation energies E* from 58 to 308 MeV, are generated by averaging the GDR strength functions predicted within the phonon damping model (PDM) using the empirical probabilities for temperature and angular momentum. The average strength functions are compared with the PDM strength functions calculated at the mean temperature and mean angular momentum, which are obtained by averaging the values of temperature and angular momentum using the same temperature and angular momentum probability distributions, respectively. It is seen that these two ways of generating the GDR linear line shape yield very similar results. It is also shown that the GDR width approaches a saturation at angular momentum J≥ 50 ℏ at T=4 MeV and at J≥ 70 ℏ at any T.

  1. Giant dipole resonance in $^{88}$Mo from phonon damping model's strength functions averaged over temperature and angular momentum distributions

    CERN Document Server

    Dang, N Dinh; Kmiecik, M; Maj, A

    2013-01-01

    The line shapes of giant dipole resonance (GDR) in the decay of the compound nucleus $^{88}$Mo, which is formed after the fusion-evaporation reaction $^{48}$Ti + $^{40}$Ca at various excitation energies $E^{*}$ from 58 to 308 MeV, are generated by averaging the GDR strength functions predicted within the phonon damping model (PDM) using the empirical probabilities for temperature and angular momentum. The average strength functions are compared with the PDM strength functions calculated at the mean temperature and mean angular momentum, which are obtained by averaging the values of temperature and angular momentum using the same temperature and angular-momentum probability distributions, respectively. It is seen that these two ways of generating the GDR linear line shape yield very similar results. It is also shown that the GDR width approaches a saturation at angular momentum $J\\geq$ 50$\\hbar$ at $T=$ 4 MeV and at $J\\geq$ 70$\\hbar$ at any $T$.

  2. Distinguishing dynamical features of water inside protein hydration layer: Distribution reveals what is hidden behind the average

    Science.gov (United States)

    Mukherjee, Saumyak; Mondal, Sayantan; Bagchi, Biman

    2017-07-01

    Since the pioneering works of Pethig, Grant, and Wüthrich on a protein hydration layer, many studies have been devoted to find out if there are any "general and universal" characteristic features that can distinguish water molecules inside the protein hydration layer from bulk. Given that the surface itself varies from protein to protein, and that each surface facing the water is heterogeneous, search for universal features has been elusive. Here, we perform an atomistic molecular dynamics simulation in order to propose and demonstrate that such defining characteristics can emerge if we look not at average properties but the distribution of relaxation times. We present results of calculations of distributions of residence times and rotational relaxation times for four different protein-water systems and compare them with the same quantities in the bulk. The distributions in the hydration layer are unusually broad and log-normal in nature due to the simultaneous presence of peptide backbones that form weak hydrogen bonds, hydrophobic amino acid side chains that form no hydrogen bond, and charged polar groups that form a strong hydrogen bond with the surrounding water molecules. The broad distribution is responsible for the non-exponential dielectric response and also agrees with large specific heat of the hydration water. Our calculations reveal that while the average time constant is just about 2-3 times larger than that of bulk water, it provides a poor representation of the real behaviour. In particular, the average leads to the erroneous conclusion that water in the hydration layer is bulk-like. However, the observed and calculated lower value of static dielectric constant of hydration layer remained difficult to reconcile with the broad distribution observed in dynamical properties. We offer a plausible explanation of these unique properties.

  3. Coordinated Control for Flywheel Energy Storage Matrix Systems for Wind Farm Based on Charging/Discharging Ratio Consensus Algorithms

    DEFF Research Database (Denmark)

    Cao, Qian; Song, Y. D.; Guerrero, Josep M.;

    2016-01-01

    This paper proposes a distributed algorithm for coordination of flywheel energy storage matrix system (FESMS) cooperated with wind farm. A simple and distributed ratio consensus algorithm is proposed to solve FESMS dispatch problem. The algorithm is based on average consensus for both undirected...

  4. Temperature-Accelerated Sampling and Amplified Collective Motion with Adiabatic Reweighting to Obtain Canonical Distributions and Ensemble Averages.

    Science.gov (United States)

    Hu, Yue; Hong, Wei; Shi, Yunyu; Liu, Haiyan

    2012-10-09

    In molecular simulations, accelerated sampling can be achieved efficiently by raising the temperature of a small number of coordinates. For collective coordinates, the temperature-accelerated molecular dynamics method or TAMD has been previously proposed, in which the system is extended by introducing virtual variables that are coupled to these coordinates and simulated at higher temperatures (Maragliano, L.; Vanden-Eijnden, E. Chem. Phys. Lett.2005, 426, 168-175). In such accelerated simulations, steady state or equilibrium distributions may exist but deviate from the canonical Boltzmann one. We show that by assuming adiabatic decoupling between the subsystems simulated at different temperatures, correct canonical distributions and ensemble averages can be obtained through reweighting. The method makes use of the low-dimensional free energy surfaces that are estimated as Gaussian mixture probability densities through maximum likelihood and expectation maximization. Previously, we proposed the amplified collective motion method or ACM. The method employs the coarse-grained elastic network model or ANM to extract collective coordinates for accelerated sampling. Here, we combine the ideas of ACM and of TAMD to develop a general technique that can achieve canonical sampling through reweighting under the adiabatic approximation. To test the validity and accuracy of adiabatic reweighting, first we consider a single n-butane molecule in a canonical stochastic heat bath. Then, we use explicitly solvated alanine dipeptide and GB1 peptide as model systems to demonstrate the proposed approaches. With alanine dipeptide, it is shown that sampling can be accelerated by more than an order of magnitude with TAMD while correct distributions and canonical ensemble averages can be recovered, necessarily through adiabatic reweighting. For the GB1 peptide, the conformational distribution sampled by ACM-TAMD, after adiabatic reweighting, suggested that a normal simulation suffered

  5. Distributed finite-time consensus tracking for nonlinear multi-agent systems with a time-varying reference state

    Science.gov (United States)

    Wen, Guoguang; Yu, Yongguang; Peng, Zhaoxia; Rahmani, Ahmed

    2016-06-01

    This paper investigates the consensus tracking problem for nonlinear multi-agent systems with a time-varying reference state. The consensus reference is taken as a virtual leader, whose output is only its position information that is available to only a subset of a group of followers. The dynamics of each follower consists of two terms: nonlinear inherent dynamics and a simple communication protocol relying only on the position of its neighbours. In this paper, the consensus tracking problem is respectively considered under fixed and switching communication topologies. Some corresponding sufficient conditions are obtained to guarantee the states of followers can converge to the state of the virtual leader in finite time. Rigorous proofs are given by using graph theory, matrix theory, and Lyapunov theory. Simulations are presented to illustrate the theoretical analysis.

  6. Distributed Consensus for Discrete-Time Directed Networks of Multiagents with Time-Delays and Random Communication Links

    Directory of Open Access Journals (Sweden)

    Yurong Liu

    2013-01-01

    Full Text Available This paper is concerned with the leader-following consensus problem in mean-square for a class of discrete-time multiagent systems. The multiagent systems under consideration are the directed and contain arbitrary discrete time-delays. The communication links are assumed to be time-varying and stochastic. It is also assumed that some agents in the network are well informed and act as leaders, and the others are followers. By introducing novel Lyapunov functionals and employing some new analytical techniques, sufficient conditions are derived to guarantee the leader-following consensus in mean-square for the concerned multiagent systems, so that all the agents are steered to an anticipated state target. A numerical example is presented to illustrate the main results.

  7. Low-power CMOS fully-folding ADC with a mixed-averaging distributed T/H circuit

    Institute of Scientific and Technical Information of China (English)

    Liu Zhen; Jia Song; Wang Yuan; Ji Lijiu; Zhang Xing

    2009-01-01

    This paper describes an 8-bit 125 Mhzlow-powerCMOS fully-foldinganalog-to-digital converter(ADC).A novel mixed-averaging distributed T/H circuit is proposed to improve the accuracy. Folding circuits are not only used in the fine converter but also in the coarse one and in the bit synchronization block to reduce the number of comparators for low power. This ADC is implemented in 0.5μm CMOS technology and occupies a die area of 2 × 1.5 mm~2. The measured differential nonlinearity and integral nonlinearity are 0.6 LSB/-0.8 LSB and 0.9 LSB/-1.2 LSB, respectively. The ADC exhibits 44.3 dB of signal-to-noise plus distortion ratio and 53.5 dB of spurious-free dynamic range for 1 MHz input sine-wave. The power dissipation is 138 mW at a sampling rate of 125 MHz at a 5 V supply.

  8. Consensus conferences

    DEFF Research Database (Denmark)

    Nielsen, Annika Porsborg; Lassen, Jesper

    Our results point to significant national variation both in terms of the perceived aim of consensus conferences, expectations to conference outcomes, conceptions of the roles of lay people and experts, and in terms of the way in which the role of public deliberation is interpreted. Interestingly...

  9. Why Consensus?

    Directory of Open Access Journals (Sweden)

    Francesca Polletta

    2016-05-01

    Full Text Available Activists have long justified their egalitarian organizational forms in prefigurative terms. Making decisions by consensus, decentralizing organization, and rotating leadership serves to model the radically democratic society that activists hope to bring into being. Our comparison of consensus-based decision-making in three historical periods, however, shows that activists have understood the purposes of prefiguration in very different ways. Whereas radical pacifists in the 1940s saw their cooperative organizations as sustaining movement stalwarts in a period of political repression, new left activists in the 1960s imagined that their radically democratic practices would be adopted by ever-widening circles. Along with the political conditions in which they have operated, activists’ distinctive understandings of equality have also shaped the way they have made decisions. Our interviews with 30 leftist activists today reveal a view of decision-making as a place to work through inequalities that are informal, unacknowledged, and pervasive.

  10. Distributional behaviors of time-averaged observables in the Langevin equation with fluctuating diffusivity: Normal diffusion but anomalous fluctuations.

    Science.gov (United States)

    Akimoto, Takuma; Yamamoto, Eiji

    2016-06-01

    We consider the Langevin equation with dichotomously fluctuating diffusivity, where the diffusion coefficient changes dichotomously over time, in order to study fluctuations of time-averaged observables in temporally heterogeneous diffusion processes. We find that the time-averaged mean-square displacement (TMSD) can be represented by the occupation time of a state in the asymptotic limit of the measurement time and hence occupation time statistics is a powerful tool for calculating the TMSD in the model. We show that the TMSD increases linearly with time (normal diffusion) but the time-averaged diffusion coefficients are intrinsically random when the mean sojourn time for one of the states diverges, i.e., intrinsic nonequilibrium processes. Thus, we find that temporally heterogeneous environments provide anomalous fluctuations of time-averaged diffusivity, which have relevance to large fluctuations of the diffusion coefficients obtained by single-particle-tracking trajectories in experiments.

  11. State Averages

    Data.gov (United States)

    U.S. Department of Health & Human Services — A list of a variety of averages for each state or territory as well as the national average, including each quality measure, staffing, fine amount and number of...

  12. Multi-beam raindrop size distributions retrievals on the Doppler spectra: Influence of averaging and mean horizontal wind correction

    NARCIS (Netherlands)

    Unal, C.M.H.

    2012-01-01

    Acquiring the raindrop size distribution (DSD) from radar data is still a challenge. For profiling radar, this distribution can be estimated from the Doppler spectra. However the Doppler spectrum is not a direct measure of the DSD. The radial component of the wind shifts the Doppler spectrum related

  13. A consensus opinion model based on the evolutionary game

    Science.gov (United States)

    Yang, Han-Xin

    2016-08-01

    We propose a consensus opinion model based on the evolutionary game. In our model, both of the two connected agents receive a benefit if they have the same opinion, otherwise they both pay a cost. Agents update their opinions by comparing payoffs with neighbors. The opinion of an agent with higher payoff is more likely to be imitated. We apply this model in scale-free networks with tunable degree distribution. Interestingly, we find that there exists an optimal ratio of cost to benefit, leading to the shortest consensus time. Qualitative analysis is obtained by examining the evolution of the opinion clusters. Moreover, we find that the consensus time decreases as the average degree of the network increases, but increases with the noise introduced to permit irrational choices. The dependence of the consensus time on the network size is found to be a power-law form. For small or larger ratio of cost to benefit, the consensus time decreases as the degree exponent increases. However, for moderate ratio of cost to benefit, the consensus time increases with the degree exponent. Our results may provide new insights into opinion dynamics driven by the evolutionary game theory.

  14. Dependence of the Population on the Temperature in the Boltzmann Distribution: A Simple Relation Involving the Average Energy

    Science.gov (United States)

    Angeli, Celestino; Cimiraglia, Renzo; Dallo, Federico; Guareschi, Riccardo; Tenti, Lorenzo

    2013-01-01

    The dependence on the temperature of the population of the "i"th state, "P"[subscript "i"], in the Boltzmann distribution is analyzed by studying its derivative with respect to the temperature, "T." A simple expression is found, involving "P"[subscript "i"], the energy of the state,…

  15. A model for light distribution and average solar irradiance inside outdoor tubular photobioreactors for the microalgal mass culture

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, F.G.A.; Camacho, F.G.; Perez, J.A.S.; Sevilla, J.M.F.; Grima, E.M. [Univ. of Almeria (Spain). Dept. of Chemical Engineering

    1997-09-05

    A mathematical model to estimate the solar irradiance profile and average light intensity inside a tubular photobioreactor under outdoor conditions is proposed, requiring only geographic, geometric, and solar position parameters. First, the length of the path into the culture traveled by any direct or disperse ray of light was calculated as the function of three variables: day of year, solar hour, and geographic latitude. Then, the phenomenon of light attenuation by biomass was studied considering Lambert-Beer`s law (only considering absorption) and the monodimensional model of Cornet et al. (1900) (considering absorption and scattering phenomena). Due to the existence of differential wavelength absorption, none of the literature models are useful for explaining light attenuation by the biomass. Therefore, an empirical hyperbolic expression is proposed. The equations to calculate light path length were substituted in the proposed hyperbolic expression, reproducing light intensity data obtained in the center of the loop tubes. The proposed model was also likely to estimate the irradiance accurately at any point inside the culture. Calculation of the local intensity was thus extended to the full culture volume in order to obtain the average irradiance, showing how the higher biomass productivities in a Phaeodactylum tricornutum UTEX 640 outdoor chemostat culture could be maintained by delaying light limitation.

  16. Non-relativistic Free–Free Emission due to the n-distribution of Electrons—Radiative Cooling and Thermally Averaged and Total Gaunt Factors

    Science.gov (United States)

    de Avillez, Miguel A.; Breitschwerdt, Dieter

    2017-09-01

    Tracking the thermal evolution of plasmas, characterized by an n-distribution, using numerical simulations, requires the determination of the emission spectra and of the radiative losses due to free–free emission from the corresponding temperature-averaged and total Gaunt factors. Detailed calculations of the latter are presented and associated with n-distributed electrons with the parameter n ranging from 1 (corresponding to the Maxwell–Boltzmann distribution) to 100. The temperature-averaged and total Gaunt factors with decreasing n tend toward those obtained with the Maxwell–Boltzmann distribution. Radiative losses due to free–free emission in a plasma evolving under collisional ionization equilibrium conditions and composed by H, He, C, N, O, Ne, Mg, Si, S, and Fe ions, are presented. These losses decrease with a decrease in the parameter n, reaching a minimum when n = 1, and thus converge with the loss of thermal plasma. Tables of the thermal-averaged and total Gaunt factors calculated for n-distributions, and a wide range of electron and photon energies, are presented.

  17. Average capacity of the ground to train communication link of a curved track in the turbulence of gamma-gamma distribution

    Science.gov (United States)

    Yang, Yanqiu; Yu, Lin; Zhang, Yixin

    2017-04-01

    A model of the average capacity of optical wireless communication link with pointing errors for the ground-to-train of the curved track is established based on the non-Kolmogorov. By adopting the gamma-gamma distribution model, we derive the average capacity expression for this channel. The numerical analysis reveals that heavier fog reduces the average capacity of link. The strength of atmospheric turbulence, the variance of pointing errors, and the covered track length need to be reduced for the larger average capacity of link. The normalized beamwidth and the average signal-to-noise ratio (SNR) of the turbulence-free link need to be increased. We can increase the transmit aperture to expand the beamwidth and enhance the signal intensity, thereby decreasing the impact of the beam wander accordingly. As the system adopting the automatic tracking of beam at the receiver positioned on the roof of the train, for eliminating the pointing errors caused by beam wander and train vibration, the equivalent average capacity of the channel will achieve a maximum value. The impact of the non-Kolmogorov spectral index's variation on the average capacity of link can be ignored.

  18. Comparison of wing-span averaging effects on lift, rolling moment, and bending moment for two span load distributions and for two turbulence representations

    Science.gov (United States)

    Lichtenstein, J. H.

    1978-01-01

    An analytical method of computing the averaging effect of wing-span size on the loading of a wing induced by random turbulence was adapted for use on a digital electronic computer. The turbulence input was assumed to have a Dryden power spectral density. The computations were made for lift, rolling moment, and bending moment for two span load distributions, rectangular and elliptic. Data are presented to show the wing-span averaging effect for wing-span ratios encompassing current airplane sizes. The rectangular wing-span loading showed a slightly greater averaging effect than did the elliptic loading. In the frequency range most bothersome to airplane passengers, the wing-span averaging effect can reduce the normal lift load, and thus the acceleration, by about 7 percent for a typical medium-sized transport. Some calculations were made to evaluate the effect of using a Von Karman turbulence representation. These results showed that using the Von Karman representation generally resulted in a span averaging effect about 3 percent larger.

  19. A Monte Carlo study for the calculation of the average linear energy transfer (LET) distributions for a clinical proton beam line and a radiobiological carbon ion beam line.

    Science.gov (United States)

    Romano, F; Cirrone, G A P; Cuttone, G; Rosa, F Di; Mazzaglia, S E; Petrovic, I; Fira, A Ristic; Varisano, A

    2014-06-21

    Fluence, depth absorbed dose and linear energy transfer (LET) distributions of proton and carbon ion beams have been investigated using the Monte Carlo code Geant4 (GEometry ANd Tracking). An open source application was developed with the aim to simulate two typical transport beam lines, one used for ocular therapy and cell irradiations with protons and the other for cell irradiations with carbon ions. This tool allows evaluation of the primary and total dose averaged LET and predict their spatial distribution in voxelized or sliced geometries. In order to reproduce the LET distributions in a realistic way, and also the secondary particles' contributions due to nuclear interactions were considered in the computations. Pristine and spread-out Bragg peaks were taken into account both for proton and carbon ion beams, with the maximum energy of 62 MeV/n. Depth dose distributions were compared with experimental data, showing good agreement. Primary and total LET distributions were analysed in order to study the influence of contributions of secondary particles in regions at different depths. A non-negligible influence of high-LET components was found in the entrance channel for proton beams, determining the total dose averaged LET by the factor 3 higher than the primary one. A completely different situation was obtained for carbon ions. In this case, secondary particles mainly contributed in the tail that is after the peak. The results showed how the weight of light and heavy secondary ions can considerably influence the computation of LET depth distributions. This has an important role in the interpretation of results coming from radiobiological experiments and, therefore, in hadron treatment planning procedures.

  20. A Monte Carlo study for the calculation of the average linear energy transfer (LET) distributions for a clinical proton beam line and a radiobiological carbon ion beam line

    Science.gov (United States)

    Romano, F.; Cirrone, G. A. P.; Cuttone, G.; Di Rosa, F.; Mazzaglia, S. E.; Petrovic, I.; Ristic Fira, A.; Varisano, A.

    2014-06-01

    Fluence, depth absorbed dose and linear energy transfer (LET) distributions of proton and carbon ion beams have been investigated using the Monte Carlo code Geant4 (GEometry ANd Tracking). An open source application was developed with the aim to simulate two typical transport beam lines, one used for ocular therapy and cell irradiations with protons and the other for cell irradiations with carbon ions. This tool allows evaluation of the primary and total dose averaged LET and predict their spatial distribution in voxelized or sliced geometries. In order to reproduce the LET distributions in a realistic way, and also the secondary particles’ contributions due to nuclear interactions were considered in the computations. Pristine and spread-out Bragg peaks were taken into account both for proton and carbon ion beams, with the maximum energy of 62 MeV/n. Depth dose distributions were compared with experimental data, showing good agreement. Primary and total LET distributions were analysed in order to study the influence of contributions of secondary particles in regions at different depths. A non-negligible influence of high-LET components was found in the entrance channel for proton beams, determining the total dose averaged LET by the factor 3 higher than the primary one. A completely different situation was obtained for carbon ions. In this case, secondary particles mainly contributed in the tail that is after the peak. The results showed how the weight of light and heavy secondary ions can considerably influence the computation of LET depth distributions. This has an important role in the interpretation of results coming from radiobiological experiments and, therefore, in hadron treatment planning procedures.

  1. Distributed parameter system coupled ARMA expansion identification and adaptive parallel IIR filtering - A unified problem statement. [Auto Regressive Moving-Average

    Science.gov (United States)

    Johnson, C. R., Jr.; Balas, M. J.

    1980-01-01

    A novel interconnection of distributed parameter system (DPS) identification and adaptive filtering is presented, which culminates in a common statement of coupled autoregressive, moving-average expansion or parallel infinite impulse response configuration adaptive parameterization. The common restricted complexity filter objectives are seen as similar to the reduced-order requirements of the DPS expansion description. The interconnection presents the possibility of an exchange of problem formulations and solution approaches not yet easily addressed in the common finite dimensional lumped-parameter system context. It is concluded that the shared problems raised are nevertheless many and difficult.

  2. A study of the b-quark fragmentation function with the DELPHI detector at LEP I and an averaged distribution obtained at the Z pole

    Energy Technology Data Exchange (ETDEWEB)

    Abdallah, J.; Antilogus, P.; Augustin, J.E.; Battaglia, M.; Behrmann, A.; Berat, C.; Silva, T. da; Jungermann, L.; Sander, C. [Univ. Pierre et Marie Curie, Univ. Paris Diderot, CNRS/IN2P3, LPNHE, Paris Cedex 05 (France); Abreu, P.; Andringa, S.; Anjos, N.; Carena, F.; Elsing, M.; Gomez-Ceballos, G.; Moraes, D.; Olshevski, A.; Passon, O.; Pierre, F.; Todorovova, S.; Vegni, G. [FCUL, LIP, IST, Lisboa Codex (Portugal); Adam, W.; Brunet, J.M.; Lamsa, J.; Liebig, W.; Lyons, L.; Maltezos, S.; Migliore, E.; Stocchi, A. [Oesterr. Akad. d. Wissensch., Institut fuer Hochenergiephysik, Vienna (Austria); Adzic, P.; Espirito Santo, M.C.; Kluit, P.; Lopez, J.M.; Mariotti, C.; Masik, J.; Myklebust, T.; Tyapkin, P.; Zintchenko, A. [N.C.S.R. Demokritos, Institute of Nuclear Physics, P.O. Box 60228, Athens (Greece); Albrecht, T.; Allmendinger, T.; Apel, W.D.; Angelis, A. de; Fassouliotis, D.; Guy, J.; Haug, S.; Hedberg, V.; Joram, C.; Kersevan, B.P.; Moa, T.; Rebecchi, P.; Salt, J.; Spassov, T.; Washbrook, A.J. [Universitaet Karlsruhe, Inst. fuer Experimentelle Kernphysik, Postfach 6980, Karlsruhe (Germany); Alemany-Fernandez, R.; Ask, S.; Augustinus, A.; Baillon, P.; Baroncelli, A.; Calvi, M.; Canale, V.; Chapkin, M.; Checchia, P.; Chliapnikov, P.; Chudoba, J.; Cieslik, K.; Ellert, M.; Flagmeyer, U.; Garcia, C.; Holmgren, S.O.; Jonsson, P.; King, B.T.; Margoni, M.; Marin, J.C.; Moch, M.; Papadopoulou, T.D.; Parodi, F.; Pimenta, M.; Podobnik, T.; Radojicic, D.; Savoy-Navarro, A.; Sosnowski, R.; Travnicek, P.; Dam, P. van; Remortel, N. van; Weiser, C. [CERN, Geneva 23 (Switzerland); Allport, P.P.; Boonekamp, M.; Bouquet, B.; Holt, P.J.; Houlden, M.A.; Kerzel, U.; Mazzucato, M.; Paiano, S.; Tkatchev, L.; Wahlen, H. [Univ. of Liverpool, Dept. of Physics, Liverpool (United Kingdom); Amaldi, U.; Bluj, M.; Buschmann, P.; Matorras, F.; Oyanguren, A.; Pukhaeva, N.; Szumlak, T.; Tome, B. [Univ. di Milano-Bicocca (Italy); INFN-MILANO, Dipt. di Fisica, Milan (Italy)] [and others

    2011-02-15

    The nature of b-quark jet hadronisation has been investigated using data taken at the Z peak by the DELPHI detector at LEP. Two complementary methods are used to reconstruct the energy of weakly decaying b-hadrons, E{sub B}{sup weak}. The average value of x{sub B}{sup weak}=E{sub B}{sup weak}/E{sub beam} is measured to be 0.699{+-}0.011. The resulting x{sub B}{sup weak} distribution is then analysed in the framework of two choices for the perturbative contribution (parton shower and Next to Leading Log QCD calculation) in order to extract measurements of the non-perturbative contribution to be used in studies of b-hadron production in other experimental environments than LEP. In the parton shower framework, data favour the Lund model ansatz and corresponding values of its parameters have been determined within PYTHIA 6.156 from DELPHI data: a= 1.84{sup +0.23}{sub -0.21} and b=0.642{sup +0.073}{sub -0.063}{proportional_to} GeV{sup -2}, with a correlation factor {rho}=92.2%. Combining the data on the b-quark fragmentation distributions with those obtained at the Z peak by ALEPH, OPAL and SLD, the average value of x{sub B}{sup weak} is found to be 0.7092{+-}0.0025 and the non-perturbative fragmentation component is extracted. Using the combined distribution, a better determination of the Lund parameters is also obtained: a= 1.48{sup +0.11}{sub -0.10} and b=0.509{sup +0.024}{sub -0.023}{proportional_to} GeV{sup -2}, with a correlation factor {rho}=92.6%. (orig.)

  3. Candidates Profile in FUVEST Exams from 2004 to 2013: Private and Public School Distribution, FUVEST Average Performance and Chemical Equilibrium Tasks Performance

    Directory of Open Access Journals (Sweden)

    R.S.A.P. Oliveira

    2014-08-01

    Full Text Available INTRODUCTION. Chemical equilibrium is recognized as a topic of several misconceptions. Its origins must be tracked from previous scholarship. Its impact on biochemistry learning is not fully described. A possible bulk of data is the FUVEST exam. OBJECTIVES: Identify students’ errors profile on chemical equilibrium tasks using public data from FUVEST exam. MATERIAL AND METHODS: Data analysis from FUVEST were: i Private and Public school distribution in Elementary and Middle School, and High School candidates of Pharmacy-Biochemistry course and total USP careers until the last call for enrollment (2004-2013; ii Average performance in 1st and 2nd parts of FUVEST exam of Pharmacy-Biochemistry, Chemistry, Engineering, Biological Sciences, Languages and Medicine courses and total enrolled candidates until 1st call for enrollment (2008- 2013; iii Performance of candidates of Pharmacy-Biochemistry, Chemistry, Engineering, Biological Sciences, Languages and Medicine courses and total USP careers in chemical equilibrium issues from 1st part of FUVEST (2011-2013. RESULTS AND DISCUSSION: i 66.2% of candidates came from private Elementary-Middle School courses and 71.8%, came from High School courses; ii Average grade over the period for 1st and 2nd FUVEST parts are respectively (in 100 points: Pharmacy-Biochemistry 66.7 and 61.2, Chemistry 65.9 and 58.9, Engineering 75.9 and 71.9, Biological Sciences 65.6 and 54.6, Languages 49.9 and 43.3, Medicine 83.5 and 79.5, total enrolled candidates 51,5 and 48.9; iii Four chemical equilibrium issues were found during 2011-2013 and the analysis of multiplechoice percentage distribution over the courses showed that there was a similar performance of students among them, except for Engineering and Medicine with higher grades, but the same proportional distribution among choices. CONCLUSION: Approved students came majorly from private schools. There was a different average performance among courses and similar on

  4. A high-density consensus map of barley to compare the distribution of QTLs for partial resistance to Puccinia hordei and of defence gene homologues

    NARCIS (Netherlands)

    Marcel, T.C.; Varshney, R.K.; Barbieri, M.; Jafary, H.; Kock, de M.J.D.; Graner, A.; Niks, R.E.

    2007-01-01

    A consensus map of barley was constructed based on three reference doubled haploid (DH) populations and three recombinant inbred line (RIL) populations. Several sets of microsatellites were used as bridge markers in the integration of those populations previously genotyped with RFLP or with AFLP mar

  5. A first-principles investigation on microscopic atom distribution and configuration-averaged properties in Cd(1-x)Zn(x)S solid solutions.

    Science.gov (United States)

    Zhou, Zhaohui; Shi, Jinwen; Wu, Po; Guo, Liejin

    2014-10-06

    The structural, energetic, and electronic properties of zincblende and wurtzite phase Cd(1-x)Zn(x)S (0≤x≤1) solid solutions were investigated by first-principles calculations. It was revealed that the trend of atom distribution in configurations with the same x value can be quantitatively characterized by the average length of the Zn-S bonds. The origin of this trend was attributed to the strong interaction of the Zn-S bonds, which acted against the aggregation of Zn atoms in this solid solution. By using a configuration-averaged method, structural and energetic properties were estimated as a function of Zn content at the level of the generalized gradient approximation, whereas electronic properties were corrected by using a hybrid functional. Phase diagrams of both solid solutions were established. An optimal x value of approximately 0.5 for photocatalytic hydrogen production was determined by taking both the band edges and band gaps into consideration; this conclusion was supported by the results of a variety of experiments.

  6. A study of the b-quark fragmentation function with the DELPHI detector at LEP I and an averaged distribution obtained at the Z Pole

    CERN Document Server

    Abdallah, J; Adam, W; Adzic, P; Albrecht, T; Alemany-Fernandez, R; Allmendinger, T; Allport, P P; Amaldi, U; Amapane, N; Amato, S; Anashkin, E; Andreazza, A; Andringa, S; Anjos, N; Antilogus, P; Apel, W-D; Arnoud, Y; Ask, S; Asman, B; Augustin, J E; Augustinus, A; Baillon, P; Ballestrero, A; Bambade, P; Barbier, R; Bardin, D; Barker, G J; Baroncelli, A; Battaglia, M; Baubillier, M; Becks, K-H; Begalli, M; Behrmann, A; Ben-Haim, E; Benekos, N; Benvenuti, A; Berat, C; Berggren, M; Bertrand, D; Besancon, M; Besson, N; Bloch, D; Blom, M; Bluj, M; Bonesini, M; Boonekamp, M; Booth, P S L; Borisov, G; Botner, O; Bouquet, B; Bowcock, T J V; Boyko, I; Bracko, M; Brenner, R; Brodet, E; Bruckman, P; Brunet, J M; Buschbeck, B; Buschmann, P; Calvi, M; Camporesi, T; Canale, V; Carena, F; Castro, N; Cavallo, F; Chapkin, M; Charpentier, Ph; Checchia, P; Chierici, R; Chliapnikov, P; Chudoba, J; Chung, S U; Cieslik, K; Collins, P; Contri, R; Cosme, G; Cossutti, F; Costa, M J; Crennell, D; Cuevas, J; D’Hondt, J; da Silva, T; Da Silva, W; Della Ricca, G; De Angelis, A; De Boer, W; De Clercq, C; De Lotto, B; De Maria, N; De Min, A; de Paula, L; Di Ciaccio, L; Di Simone, A; Doroba, K; Drees, J; Eigen, G; Ekelof, T; Ellert, M; Elsing, M; Espirito Santo, M C; Fanourakis, G; Fassouliotis, D; Feindt, M; Fernandez, J; Ferrer, A; Ferro, F; Flagmeyer, U; Foeth, H; Fokitis, E; Fulda-Quenzer, F; Fuster, J; Gandelman, M; Garcia, C; Gavillet, Ph; Gazis, E; Gokieli, R; Golob, B; Gomez-Ceballos, G; Goncalves, P; Graziani, E; Grosdidier, G; Grzelak, K; Guy, J; Haag, C; Hallgren, A; Hamacher, K; Hamilton, K; Haug, S; Hauler, F; Hedberg, V; Hennecke, M; Hoffman, J; Holmgren, S-O; Holt, P J; Houlden, M A; Jackson, J N; Jarlskog, G; Jarry, P; Jeans, D; Johansson, E K; Jonsson, P; Joram, C; Jungermann, L; Kapusta, F; Katsanevas, S; Katsoufis, E; Kernel, G; Kersevan, B P; Kerzel, U; King, B T; Kjaer, N J; Kluit, P; Kokkinias, P; Kourkoumelis, C; Kouznetsov, O; Krumstein, Z; Kucharczyk, M; Lamsa, J; Leder, G; Ledroit, F; Leinonen, L; Leitner, R; Lemonne, J; Lepeltier, V; Lesiak, T; Liebig, W; Liko, D; Lipniacka, A; H Lopes, J; Lopez, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J; Malek, A; Maltezos, S; Mandl, F; Marco, J; Marco, R; Marechal, B; Margoni, M; Marin, J-C; Mariotti, C; Markou, A; Martinez-Rivero, C; Masik, J; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Mazzucato, F; Mazzucato, M; McNulty, R; Meroni, C; Migliore, E; Mitaroff, W; Mjoernmark, U; Moa, T; Moch, M; Moenig, K; Monge, R; Montenegro, J; Moraes, D; Moreno, S; Morettini, P; Mueller, U; Muenich, K; Mulders, M; Mundim, L; Murray, W; Muryn, B; Myatt, G; Myklebust, T; Nassiakou, M; Navarria, F; Nawrocki, K; Nemecek, S; Nicolaidou, R; Nikolenko, M; Oblakowska-Mucha, A; Obraztsov, V; Olshevski, A; Onofre, A; Orava, R; Osterberg, K; Ouraou, A; Oyanguren, A; Paganoni, M; Paiano, S; Palacios, J P; Palka, H; Papadopoulou, Th D; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Peralta, L; Perepelitsa, V; Perrotta, A; Petrolini, A; Piedra, J; Pieri, L; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Poireau, V; Pol, M E; Polok, G; Pozdniakov, V; Pukhaeva, N; Pullia, A; Radojicic, D; Rebecchi, P; Rehn, J; Reid, D; Reinhardt, R; Renton, P; Richard, F; Ridky, J; Rivero, M; Rodriguez, D; Romero, A; Ronchese, P; Roudeau, P; Rovelli, T; Ruhlmann-Kleider, V; Ryabtchikov, D; Sadovsky, A; Salmi, L; Salt, J; Sander, C; Savoy-Navarro, A; Schwickerath, U; Sekulin, R; Siebel, M; Sisakian, A; Smadja, G; Smirnova, O; Sokolov, A; Sopczak, A; Sosnowski, R; Spassov, T; Stanitzki, M; Stocchi, A; Strauss, J; Stugu, B; Szczekowski, M; Szeptycka, M; Szumlak, T; Tabarelli, T; Tegenfeldt, F; Timmermans, J; Tkatchev, L; Tobin, M; Todorovova, S; Tome, B; Tonazzo, A; Tortosa, P; Travnicek, P; Treille, D; Tristram, G; Trochimczuk, M; Troncon, C; Turluer, M-L; Tyapkin, I A; Tyapkin, P; Tzamarias, S; Uvarov, V; Valenti, G; Van Dam, P; Van Eldik, J; van Remortel, N; Van Vulpen, I; Vegni, G; Veloso, F; Venus, W; Verdier, P; Verzi, V; Vilanova, D; Vitale, L; Vrba, V; Wahlen, H; Washbrook, A J; Weiser, C; Wicke, D; Wickens, J; Wilkinson, G; Winter, M; Witek, M; Yushchenko, O; Zalewska, A; Zalewski, P; Zavrtanik, D; Zhuravlov, V; Zimin, N I; Zintchenko, A; Zupan, M

    2011-01-01

    The nature of b-quark jet hadronisation has been investigated using data taken at the Z peak by the DELPHI detector at LEP. Two complementary methods are used to reconstruct the energy of weakly decaying b-hadrons, E^weak_B. The average value of x^weak_B = E^weak_B/E_beam is measured to be 0.699 +/- 0.011. The resulting x^weak_B distribution is then analysed in the framework of two choices for the perturbative contribution (parton shower and Next to Leading Log QCD calculation) in order to extract measurements of the non-perturbative contribution to be used in studies of b-hadron production in other experimental environments than LEP. In the parton shower framework, data favour the Lund model ansatz and corresponding values of its parameters have been determined within PYTHIA~6.156 from DELPHI data: a= 1.84^{+0.23}_{-0.21} and b=0.642^{+0.073}_{-0.063} GeV^-2, with a correlation factor rho = 92.2%. Combining the data on the b-quark fragmentation distributions with those obtained at the Z peak by ALEPH, OPAL a...

  7. The Method of Average Fairness Degree for Seats Distribution%席位分配的平均公平度方法

    Institute of Scientific and Technical Information of China (English)

    丁会; 李波

    2013-01-01

    定义个体相对于总体的公平程度,即个体公平度与总体绝对公平度的比值,当比值趋于1时,就说明分配方案使该个体满意.利用方差的概念定义平均公平度,使个体公平程度相对于总体的公平程度的差距最小,等价于每一个个体公平度都很接近,并且趋于1,每个个体的公平程度达到最大,此时座位分配最为公平.%The definition of individual fairness degree which is relative to the overall is the ratio of individual fairness degree to the overall absolute fairness.When the ratio tends to be 1,it means the distribution plan satisfies the individual.By using the concept of variance,the average fairness degree is defined.Meanwhile,the difference between individual and overall fairness degrees can be minimized.Furthermore,every individual fairness degree is close to each other and tends to be 1.Consequently,every individual fairness degree tends to be maximized.Therefore,the seats distribution scheme is most fair for everyone.

  8. Consensus theoretic classification methods

    Science.gov (United States)

    Benediktsson, Jon A.; Swain, Philip H.

    1992-01-01

    Consensus theory is adopted as a means of classifying geographic data from multiple sources. The foundations and usefulness of different consensus theoretic methods are discussed in conjunction with pattern recognition. Weight selections for different data sources are considered and modeling of non-Gaussian data is investigated. The application of consensus theory in pattern recognition is tested on two data sets: 1) multisource remote sensing and geographic data and 2) very-high-dimensional remote sensing data. The results obtained using consensus theoretic methods are found to compare favorably with those obtained using well-known pattern recognition methods. The consensus theoretic methods can be applied in cases where the Gaussian maximum likelihood method cannot. Also, the consensus theoretic methods are computationally less demanding than the Gaussian maximum likelihood method and provide a means for weighting data sources differently.

  9. Quantifying the degree of bias from using county-scale data in species distribution modeling: Can increasing sample size or using county-averaged environmental data reduce distributional overprediction?

    Science.gov (United States)

    Collins, Steven D; Abbott, John C; McIntyre, Nancy E

    2017-08-01

    Citizen-science databases have been used to develop species distribution models (SDMs), although many taxa may be only georeferenced to county. It is tacitly assumed that SDMs built from county-scale data should be less precise than those built with more accurate localities, but the extent of the bias is currently unknown. Our aims in this study were to illustrate the effects of using county-scale data on the spatial extent and accuracy of SDMs relative to true locality data and to compare potential compensatory methods (including increased sample size and using overall county environmental averages rather than point locality environmental data). To do so, we developed SDMs in maxent with PRISM-derived BIOCLIM parameters for 283 and 230 species of odonates (dragonflies and damselflies) and butterflies, respectively, for five subsets from the OdonataCentral and Butterflies and Moths of North America citizen-science databases: (1) a true locality dataset, (2) a corresponding sister dataset of county-centroid coordinates, (3) a dataset where the average environmental conditions within each county were assigned to each record, (4) a 50/50% mix of true localities and county-centroid coordinates, and (5) a 50/50% mix of true localities and records assigned the average environmental conditions within each county. These mixtures allowed us to quantify the degree of bias from county-scale data. Models developed with county centroids overpredicted the extent of suitable habitat by 15% on average compared to true locality models, although larger sample sizes (>100 locality records) reduced this disparity. Assigning county-averaged environmental conditions did not offer consistent improvement, however. Because county-level data are of limited value for developing SDMs except for species that are widespread and well collected or that inhabit regions where small, climatically uniform counties predominate, three means of encouraging more accurate georeferencing in citizen

  10. Model-based consensus

    NARCIS (Netherlands)

    M. Boumans

    2014-01-01

    The aim of the rational-consensus method is to produce "rational consensus", that is, "mathematical aggregation", by weighing the performance of each expert on the basis of his or her knowledge and ability to judge relevant uncertainties. The measurement of the performance of the experts is based on

  11. The Limits of Consensus.

    Science.gov (United States)

    Poster, John B.

    Dynamics in the education policy arena suggest that, despite two generations of researchers extolling democratic leadership styles and consensus building over autocratic techniques, wide participation in policymaking and the broadest possible consensus are not always productive: American society has not yet agreed on what schools should…

  12. Classic maximum entropy recovery of the average joint distribution of apparent FRET efficiency and fluorescence photons for single-molecule burst measurements.

    Science.gov (United States)

    DeVore, Matthew S; Gull, Stephen F; Johnson, Carey K

    2012-04-05

    We describe a method for analysis of single-molecule Förster resonance energy transfer (FRET) burst measurements using classic maximum entropy. Classic maximum entropy determines the Bayesian inference for the joint probability describing the total fluorescence photons and the apparent FRET efficiency. The method was tested with simulated data and then with DNA labeled with fluorescent dyes. The most probable joint distribution can be marginalized to obtain both the overall distribution of fluorescence photons and the apparent FRET efficiency distribution. This method proves to be ideal for determining the distance distribution of FRET-labeled biomolecules, and it successfully predicts the shape of the recovered distributions.

  13. Practical Techniques for Achieving Consensus.

    Science.gov (United States)

    Kline, John A.

    Consensus is important in the making of a policy decision. If a decision is reached without consensus, morale and unit satisfaction may both suffer. With genuine consensus, a unit tends to willingly support and implement the new policy. After analyzing how observed small groups had actually reached consensus, the following ten techniques were…

  14. Differential modulation of prM cleavage, extracellular particle distribution, and virus infectivity by conserved residues at nonfurin consensus positions of the dengue virus pr-M junction.

    Science.gov (United States)

    Junjhon, Jiraphan; Lausumpao, Matthawee; Supasa, Sunpetchuda; Noisakran, Sansanee; Songjaeng, Adisak; Saraithong, Prakaimuk; Chaichoun, Kridsada; Utaipat, Utaiwan; Keelapang, Poonsook; Kanjanahaluethai, Amornrat; Puttikhunt, Chunya; Kasinrerk, Watchara; Malasit, Prida; Sittisombut, Nopporn

    2008-11-01

    In the generation of flavivirus particles, an internal cleavage of the envelope glycoprotein prM by furin is required for the acquisition of infectivity. Unlike cleavage of the prM of other flaviviruses, cleavage of dengue virus prM is incomplete in many cell lines; the partial cleavage reflects the influence of residues at furin nonconsensus positions of the pr-M junction, as flaviviruses share basic residues at positions P1, P2, and P4, recognized by furin. In this study, viruses harboring the alanine-scanning and other multiple-point mutations of the pr-M junction were generated, employing a dengue virus background that exhibited 60 to 70% prM cleavage and a preponderance of virion-sized extracellular particles. Analysis of prM and its cleavage products in viable mutants revealed a cleavage-suppressive effect at the conserved P3 Glu residue, as well as the cleavage-augmenting effects at the P5 Arg and P6 His residues, indicating an interplay between opposing modulatory influences mediated by these residues on the cleavage of the pr-M junction. Changes in the prM cleavage level were associated with altered proportions of extracellular virions and subviral particles; mutants with reduced cleavage were enriched with subviral particles and prM-containing virions, whereas the mutant with enhanced cleavage was deprived of these particles. Alterations of virus multiplication were detected in mutants with reduced prM cleavage and were correlated with their low specific infectivities. These findings define the functional roles of charged residues located adjacent to the furin consensus sequence in the cleavage of dengue virus prM and provide plausible mechanisms by which the reduction in the pr-M junction cleavability may affect virus replication.

  15. 快速一致性控制算法下的多 UAV分布式协同控制%Distributed Cooperative Control for Multi-UAV Based on Fast Consensus Control Algorithm

    Institute of Scientific and Technical Information of China (English)

    贾方超; 姚佩阳; 马方方; 李巧丽

    2014-01-01

    Consistent system state is the basis of distributed cooperative control in multi-UAV system,and consensus control algorithm is an effective method for the multi-UAV system to achieve consistent state . Under communication constraints,the UAV platform is controlled to evolve to the consistent system state through the consensus control algorithm based on local information interaction .To solve the unfeasibility of changing the communication topology and of multi-hop routing communication,a new fast consensus control algorithm was designed by introducing state difference and predictive state .Theorems about convergence and efficiency of the new algorithm were introduced with a rigorous mathematical proof .Fast task coordination was achieved under distributed cooperative control structure .Theoretical analysis and simulation results verify the feasibility and effectiveness of the algorithm .%多无人机系统中,系统状态的一致性是实现多无人机分布式协同控制的基础,一致性控制算法是多无人机系统实现状态一致的有效方法。通信约束条件下,无人机平台基于局部交互信息,通过一致性控制算法,控制系统状态演化一致。为解决改变通信拓扑结构和多跳路由通信的不可操作性问题,引入状态差值和预测状态,设计新的快速一致性控制算法。给出新算法收敛性和快速性的相关定理,并进行了严格的数学证明,在分布式协同控制结构下实现多无人机快速任务协同。理论分析和仿真实验验证了算法的可行性和有效性。

  16. On Conditions for Convergence to Consensus

    CERN Document Server

    Lorenz, Jan

    2008-01-01

    A new theorem on conditions for convergence to consensus of a multiagent time-dependent time-discrete dynamical system is presented. The theorem is build up on the notion of averaging maps. We compare this theorem to Moreau's Theorem and his proposed set-valued Lyapunov theory (IEEE Transactions on Automatic Control, vol. 50, no. 2, 2005). We give examples that point out differences of approaches including examples where Moreau's theorem is not applicable but ours is. Further on, we give examples that demonstrate that the theory of convergence to consensus is still not complete.

  17. Analyzing the average intensity distribution and beam width evolution of phase-locked partially coherent radial flat-topped array laser beams in oceanic turbulence

    Science.gov (United States)

    Yousefi, M.; Kashani, F. D.; Mashal, A.

    2017-02-01

    In this research, an analytical expression for cross-spectral density matrix elements (and consequently, average intensity) of partially coherent flat-topped (PCFT) radial array laser beams in weak oceanic turbulence are derived based on the extended Huygens-Fresnel principle and the previously developed knowledge of the propagation of a partially coherent beam in atmosphere. Mean-squared beam width is calculated analytically using average intensity formula. The simulation is done by considering the effects of source parameters (such as the radius of the array setup’s circle and effective width of spectral degree of coherence) and turbulent ocean factors (such as the rate of dissipation of the turbulent kinetic energy per unit mass of fluid and relative strength of temperature-salinity fluctuations, Kolmogorov micro-scale, and the rate of dissipation of the mean squared temperature) in detail. It is found that when salinity fluctuations in the ocean dominate temperature fluctuations, the average intensity of the PCFT array beam becomes more broad and the array beam profile conversion process to a single wider Gaussian beam profile will occur at a faster rate. For the same turbulent conditions and the same initial beam width, the divergence of a flat-topped array beam is less than the Gaussian array beam. The simulation and calculation results are shown by graphs.

  18. Containment and Consensus-based Distributed Coordination Control to Achieve Bounded Voltage and Precise Reactive Power Sharing in Islanded AC Microgrids

    DEFF Research Database (Denmark)

    Han, Renke; Meng, Lexuan; Ferrari-Trecate, Giancarlo

    2017-01-01

    This paper presents a novel distributed approach to achieve both bounded voltage and accurate reactive power sharing regulation in AC microgrid. The coupling/trade-off effects between bus voltages and reactive power sharing regulation are first analyzed in detail to provide a guideline for coordi...

  19. Longitudinal temperature distribution in an end-pumped solid-state amplifier medium: application to a high average power diode pumped Yb:YAG thin disk amplifier.

    Science.gov (United States)

    Bourdet, Gilbert L; Yu, Haiwu

    2007-08-10

    We propose a simple analytical derivation making it possible to compute a one-dimensional temperature variation in an end-pumped solid-state laser. This derivation takes into account the pump intensity variation along the crystal, the doping concentration, and temperature dependence of the thermal conductivity. We then compare this simulation with the one usually used, which does not take into account any of these dependences. The results show that, at room temperature, the two methods are in good agreement, but at a cryogenic temperature where the thermal conductivity varies fast with temperature, a large discrepancy is found, and the conventional computations underestimate both the average temperature and the longitudinal gradient.

  20. The Consensus: Another View.

    Science.gov (United States)

    Brown, H. Douglas

    1984-01-01

    Comments on the seven points of consensus presented in "A Theoretical Basis for Teaching the Receptive Skills" by Stephen Krashen, et al., particularly on the terminology that is derived from Krashen's other writings. Offers eight statements which reflect in more general terms an interpretation of Krashen's theories for language teachers…

  1. Model-based consensus

    NARCIS (Netherlands)

    Boumans, Marcel

    2014-01-01

    The aim of the rational-consensus method is to produce “rational consensus”, that is, “mathematical aggregation”, by weighing the performance of each expert on the basis of his or her knowledge and ability to judge relevant uncertainties. The measurement of the performance of the experts is based on

  2. A Delphic consensus assessment

    DEFF Research Database (Denmark)

    Oberg, Kjell; Krenning, Eric; Sundin, Anders

    2016-01-01

    and pancreastatin); monoanalyte measurements; and lack sensitivity, specificity and predictive capacity. None of them meet the NIH metrics for clinical usage. A multinational, multidisciplinary Delphi consensus meeting of NEN experts (n = 33) assessed current imaging strategies and biomarkers in NEN management...

  3. Making Consensus Tractable

    CERN Document Server

    Mossel, Elchanan

    2010-01-01

    The process of consensus voting has many distinct advantages: it fosters discussion and participation, empowers minorities and independent thinkers, and is more likely, after a decision has been made, to secure the participants' support for the chosen course of action. The disadvantage of consensus decision making is, of course, the difficulty of reaching consensus. While this challenge is largely overcome in many theoretical settings such as Aumann's ``agree to disagree'' result, a hitherto unsolved difficulty is the lack of a framework offering rational (i.e., Bayesian) consensus decision making that can be performed using simple and efficient calculations. We propose a model featuring two possible states of the world and a finite number of individuals. The group has to come to a binary decision, where the merit of each of the two possible courses of action depends on the state of the world. Each member of the group has a private and independent signal at his or her disposal, giving some indication as to wh...

  4. Consensus and Synchronization in Complex Networks

    CERN Document Server

    2013-01-01

    Synchronization in complex networks is one of the most captivating cooperative phenomena in nature and has been shown to be of fundamental importance in such varied circumstances as the continued existence of species, the functioning of heart pacemaker cells, epileptic seizures, neuronal firing in the feline visual cortex and cognitive tasks in humans. E.g. coupled visual and acoustic interactions make fireflies flash, crickets chirp, and an audience clap in unison. On the other hand, in distributed systems and networks, it is often necessary for some or all of the nodes to calculate some function of certain parameters, e.g. sink nodes in sensor networks being tasked with calculating the average measurement value of all the sensors or multi-agent systems in which all agents are required to coordinate their speed and direction. When all nodes calculate the same function of the initial values in the system, they are said to reach consensus. Such concepts - sometimes also called state agreement, rendezvous, and ...

  5. Consensus Based Distributed Formation Control of Quadrotor UAVs%基于一致性理论的四旋翼无人机分布式编队控制方法

    Institute of Scientific and Technical Information of China (English)

    李磊; 李小民; 郑忠贵; 张国荣

    2015-01-01

    A distributed control method for formation of quadrotor UAVs is presented with introductions on the fundamental knowledge of graph theory and consensus of swarm system. The quadrotor UAV is described as a second-order integrator dynamic system, and the relative position is used to describe the UAV formation shape. The quadrotor UAV formation is modeled based on the communication topology relationship of quadrotors. The strategy of follower-leader method integrated with graph-based method is explored. A second-order consensus algorithm is presented, with which the fleet can complete formation gathering and formation maneuvering. Finally, the effectiveness of this algorithm is shown through the simulation results.%介绍了图论和群体系统一致性的相关理论,提出一种分布式四旋翼无人机编队控制方法,将四旋翼无人机描述为二阶积分器动力系统,采用相对位置偏差描述编队队形;根据四旋翼无人机之间通信拓扑关系将四旋翼无人机编队建模为图,探索了领航跟随法和基于图论法的融合策略,给出一种有领航者的二阶一致性算法。在该算法下,编队可以完成编队集结和编队机动等行为,最后通过仿真实验验证了该方法的有效性。

  6. Consensus of Multiagent Systems with Sampled Information and Noisy Measurements

    Directory of Open Access Journals (Sweden)

    Zhao-Jun Tang

    2013-01-01

    Full Text Available We consider consensus problems of first-order multiagent systems with sampled information and noisy measurements. A distributed stochastic approximation type algorithm is employed to attenuate the measurement noises. We provide conditions under which almost sure strong consensus is guaranteed for fixed and switching directed network topologies. Simulation results are provided to illustrate the theoretical results.

  7. Finite-time consensus of heterogeneous multi-agent systems

    Institute of Scientific and Technical Information of China (English)

    Zhu Ya-Kun; Guan Xin-Ping; Luo Xiao-Yuan

    2013-01-01

    We investigate the finite-time consensus problem for heterogeneous multi-agent systems composed of first-order and second-order agents.A novel continuous nonlinear distributed consensus protocol is constructed,and finite-time consensus criteria are obtained for the heterogeneous multi-agent systems.Compared with the existing results,the stationary and kinetic consensuses of the heterogeneous multi-agent systems can be achieved in a finite time respectively.Moreover,the leader can be a first-order or a second-order integrator agent.Finally,some simulation examples are employed to verify the efficiency of the theoretical results.

  8. A New Foreign Policy Consensus?

    Science.gov (United States)

    Melanson, Richard A.

    1990-01-01

    Discusses the achievements of Reagan's foreign policy. Explores the question: Did Reagan reconstruct a domestic foreign policy consensus? Concludes that no consensus was reached. Analyzes Reagan's political beliefs, including his antinuclear sentiments, and examines relations between Reagan and Congress. (RW)

  9. Achieving diagnosis by consensus

    LENUS (Irish Health Repository)

    Kane, Bridget

    2009-08-01

    This paper provides an analysis of the collaborative work conducted at a multidisciplinary medical team meeting, where a patient’s definitive diagnosis is agreed, by consensus. The features that distinguish this process of diagnostic work by consensus are examined in depth. The current use of technology to support this collaborative activity is described, and experienced deficiencies are identified. Emphasis is placed on the visual and perceptual difficulty for individual specialities in making interpretations, and on how, through collaboration in discussion, definitive diagnosis is actually achieved. The challenge for providing adequate support for the multidisciplinary team at their meeting is outlined, given the multifaceted nature of the setting, i.e. patient management, educational, organizational and social functions, that need to be satisfied.

  10. Spanish Consensus Statement

    Science.gov (United States)

    Rey, Guillermo Álvarez; Cuesta, Jordi Ardevol; Loureda, Rafael Arriaza; España, Fernando Ávila; Matas, Ramón Balius; Pazos, Fernando Baró; de Dios Beas Jiménez, Juan; Rosell, Jorge Candel; Fernandez, César Cobián; Ros, Francisco Esparza; Colmenero, Josefina Espejo; de Prado, Jorge Fernández; Cota, Juan José García; González, Jose Ignacio Garrido; Santander, Manuela González; Munilla, Miguel Ángel Herrador; Ruiz, Francisco Ivorra; Díaz, Fernando Jiménez; Marqueta, Pedro Manonelles; Fernandez, Antonio Maestro; Benito, Juan José Muñoz; Vilás, Ramón Olivé; Teres, Xavier Peirau; Amaro, José Peña; Roque, Juan Pérez San; Parenteu, Christophe Ramírez; Serna, Juan Ribas; Álvarez, Mikel Sánchez; Marchori, Carlos Sanchez; Soto, Miguel del Valle; Alonso, José María Villalón; García, Pedro Guillen; de la Iglesia, Nicolas Hugo; Alcorocho, Juan Manuel Lopez

    2016-01-01

    On the 21st of March, 2015, experts met at Clínica CEMTRO in Madrid, Spain, under the patronage of The Spanish Society for Sports Traumatology (SETRADE), The Spanish Federation of Sports Medicine (FEMEDE), The Spanish Association of Medical Services for Football Clubs (AEMEF), and The Spanish Association of Medical Services for Basketball Clubs (AEMB) with the aim of establishing a round table that would allow specialists to consider the most appropriate current general actions to be taken when treating muscle tears in sport, based on proven scientific data described in the medical literature. Each expert received a questionnaire prior to the aforementioned meeting comprising a set of questions concerning therapeutic indications generally applied in the different stages present during muscle repair. The present Consensus Document is the result of the answers to the questionnaire and resulting discussion and consensus over which are the best current indications in the treatment of muscle tears in sport. Avoiding immobilization, not taking nonsteroidal anti-inflammatory drugs (NSAIDs) randomly, fostering early mobilization, increasing vascularization of injured, site and regulating inflammatory mechanisms—without inhibiting these from the early stages of the recovery period—all stood out as main points of the Consensus Document. Additionally, there is controversy concerning cell stimulation techniques and the use of growth factors or cell inhibitors. The decision concerning discharge was unanimous, as was the criteria considered when it came to performing sport techniques without pain. PMID:27213161

  11. Distributed Detection over Time Varying Networks: Large Deviations Analysis

    CERN Document Server

    Bajovic, Dragana; Xavier, Joao; Sinopoli, Bruno; Moura, Jose M F

    2010-01-01

    We apply large deviations theory to study asymptotic performance of running consensus distributed detection in sensor networks. Running consensus is a stochastic approximation type algorithm, recently proposed. At each time step k, the state at each sensor is updated by a local averaging of the sensor's own state and the states of its neighbors (consensus) and by accounting for the new observations (innovation). We assume Gaussian, spatially correlated observations. We allow the underlying network be time varying, provided that the graph that collects the union of links that are online at least once over a finite time window is connected. This paper shows through large deviations that, under stated assumptions on the network connectivity and sensors' observations, the running consensus detection asymptotically approaches in performance the optimal centralized detection. That is, the Bayes probability of detection error (with the running consensus detector) decays exponentially to zero as k goes to infinity at...

  12. Learning consensus in adversarial environments

    Science.gov (United States)

    Vamvoudakis, Kyriakos G.; García Carrillo, Luis R.; Hespanha, João. P.

    2013-05-01

    This work presents a game theory-based consensus problem for leaderless multi-agent systems in the presence of adversarial inputs that are introducing disturbance to the dynamics. Given the presence of enemy components and the possibility of malicious cyber attacks compromising the security of networked teams, a position agreement must be reached by the networked mobile team based on environmental changes. The problem is addressed under a distributed decision making framework that is robust to possible cyber attacks, which has an advantage over centralized decision making in the sense that a decision maker is not required to access information from all the other decision makers. The proposed framework derives three tuning laws for every agent; one associated with the cost, one associated with the controller, and one with the adversarial input.

  13. Achieving consensus in environmental programs

    Energy Technology Data Exchange (ETDEWEB)

    Kurstedt, Jr., H. A.; Jones, R. M.; Walker, J. A.; Middleman, L. I.

    1989-01-01

    In this paper, we describe a new research effort on consensus tied to the Environmental Restoration Program (ERP) within the US Department of Energy's Office of Defense Waste and Transportation Management (DWTM). We define consensus and explain why consensus decisions are not merely desirable but necessary in furthering ERP activities. As examples of our planned applied research, we first discuss Nominal Group Technique as a representative consensus-generating tool, and we conclude by describing the consensus-related mission of the Waste Management Review Group, established at Virginia Tech to conduct independent, third-party review of DWTM/ERP plans and activities. 10 refs.

  14. Multiscale Gossip for Efficient Decentralized Averaging in Wireless Packet Networks

    CERN Document Server

    Tsianos, Konstantinos I

    2010-01-01

    This paper describes and analyzes a hierarchical gossip algorithm for solving the distributed average consensus problem in wireless sensor networks. The network is recursively partitioned into subnetworks. Initially, nodes at the finest scale gossip to compute local averages. Then, using geographic routing to enable gossip between nodes that are not directly connected, these local averages are progressively fused up the hierarchy until the global average is computed. We show that the proposed hierarchical scheme with $k$ levels of hierarchy is competitive with state-of-the-art randomized gossip algorithms, in terms of message complexity, achieving $\\epsilon$-accuracy with high probability after $O\\big(n \\log \\log n \\log \\frac{kn}{\\epsilon} \\big)$ messages. Key to our analysis is the way in which the network is recursively partitioned. We find that the optimal scaling law is achieved when subnetworks at scale $j$ contain $O(n^{(2/3)^j})$ nodes; then the message complexity at any individual scale is $O(n \\log \\...

  15. Leader-Based Consensus of Heterogeneous Nonlinear Multiagent Systems

    Directory of Open Access Journals (Sweden)

    Tairen Sun

    2014-01-01

    Full Text Available This paper considers the leader-based consensus of heterogeneous multiple agents with nonlinear uncertain systems. Based on the information obtained from the following agents’ neighbors, leader observers are designed by the following agents to estimate the leader’s states and nonlinear dynamics. Then, to achieve leader-based consensus, adaptive distributed controllers are designed for the following agents to track the designed corresponding leader observers. The effectiveness of the leader observers and distributed consensus controllers are illustrated by formal proof and simulation results.

  16. Microscopic enteritis: Bucharest consensus.

    Science.gov (United States)

    Rostami, Kamran; Aldulaimi, David; Holmes, Geoffrey; Johnson, Matt W; Robert, Marie; Srivastava, Amitabh; Fléjou, Jean-François; Sanders, David S; Volta, Umberto; Derakhshan, Mohammad H; Going, James J; Becheanu, Gabriel; Catassi, Carlo; Danciu, Mihai; Materacki, Luke; Ghafarzadegan, Kamran; Ishaq, Sauid; Rostami-Nejad, Mohammad; Peña, A Salvador; Bassotti, Gabrio; Marsh, Michael N; Villanacci, Vincenzo

    2015-03-07

    Microscopic enteritis (ME) is an inflammatory condition of the small bowel that leads to gastrointestinal symptoms, nutrient and micronutrient deficiency. It is characterised by microscopic or sub-microscopic abnormalities such as microvillus changes and enterocytic alterations in the absence of definite macroscopic changes using standard modern endoscopy. This work recognises a need to characterize disorders with microscopic and submicroscopic features, currently regarded as functional or non-specific entities, to obtain further understanding of their clinical relevance. The consensus working party reviewed statements about the aetiology, diagnosis and symptoms associated with ME and proposes an algorithm for its investigation and treatment. Following the 5(th) International Course in Digestive Pathology in Bucharest in November 2012, an international group of 21 interested pathologists and gastroenterologists formed a working party with a view to formulating a consensus statement on ME. A five-step agreement scale (from strong agreement to strong disagreement) was used to score 21 statements, independently. There was strong agreement on all statements about ME histology (95%-100%). Statements concerning diagnosis achieved 85% to 100% agreement. A statement on the management of ME elicited agreement from the lowest rate (60%) up to 100%. The remaining two categories showed general agreement between experts on clinical presentation (75%-95%) and pathogenesis (80%-90%) of ME. There was strong agreement on the histological definition of ME. Weaker agreement on management indicates a need for further investigations, better definitions and clinical trials to produce quality guidelines for management. This ME consensus is a step toward greater recognition of a significant entity affecting symptomatic patients previously labelled as non-specific or functional enteropathy.

  17. Continuity and consensus

    DEFF Research Database (Denmark)

    Abrahamson, Peter

    2010-01-01

    maternal leave. These changes can be explained as adjustments to post-industrial conditions within a political culture relying on class compromises and a broad consensus informed by expert advice coming from civil servants and ad hoc policy commissions. The paper concludes that changes in Danish family......In Danish family policy, changes initiated by the present conservative-liberal government differ little from those proposed by the opposition. Recent changes are minor, but significant ones occurred in the 1960s, when childcare was universalized, and in the 1980s, when parental leave substituted...

  18. Consensus networks with time-delays over finite fields

    Science.gov (United States)

    Li, Xiuxian; Su, Housheng; Chen, Michael Z. Q.

    2016-05-01

    In this paper, we investigate the consensus problem in networks with time-delays over finite fields. The delays are categorised into three cases: single constant delay, multiple constant delays, and time-varying bounded delays. For all cases, some sufficient and necessary conditions for consensus are derived. Furthermore, assuming that the communication graph is strongly connected, some of the obtained necessary conditions reveal that the conditions for consensus with time-delays over finite fields depend not only on the diagonal entries but also on the off-diagonal entries, something that is intrinsically distinct from the case over real numbers (where having at least one nonzero diagonal entry is a sufficient and necessary condition to guarantee consensus). In addition, it is shown that delayed networks cannot achieve consensus when the interaction graph is a tree if the corresponding delay-free networks cannot reach consensus, which is consistent with the result over real numbers. As for average consensus, we show that it can never be achieved for delayed networks over finite fields, although it indeed can be reached under several conditions for delay-free networks over finite fields. Finally, networks with time-varying delays are discussed and one sufficient condition for consensus is presented by graph-theoretic method.

  19. Conflict or Consensus?

    DEFF Research Database (Denmark)

    Agger, Annika; Poulsen, Birgitte

    forms of institutional design of citizen participation processes, less attention has been paid to the role of public administrators, and their role in facilitating processes of citizen participation. Public administrators have to work with diverse groups of citizens with diverging, and often conflicting......, interests. However, many public administrators have not been adequately exposed to the rationales of conflicts and the skills in resolving conflicts. The aim of this paper is to analyse the different types of conflicts that public administrators experience in formal processes of citizen involvement. Whereas...... the literature of deliberative democracy claims that consensus is most often the result of rational deliberative processes, the claim of this paper is that conflicts is more likely a natural and integrated part of such deliberative acts. Conflicts are, thus, seen as inevitable. Also conflicts may function...

  20. On consensus biomarker selection

    Directory of Open Access Journals (Sweden)

    Gambin Anna

    2007-05-01

    Full Text Available Abstract Background Recent development of mass spectrometry technology enabled the analysis of complex peptide mixtures. A lot of effort is currently devoted to the identification of biomarkers in human body fluids like serum or plasma, based on which new diagnostic tests for different diseases could be constructed. Various biomarker selection procedures have been exploited in recent studies. It has been noted that they often lead to different biomarker lists and as a consequence, the patient classification may also vary. Results Here we propose a new approach to the biomarker selection problem: to apply several competing feature ranking procedures and compute a consensus list of features based on their outcomes. We validate our methods on two proteomic datasets for the diagnosis of ovarian and prostate cancer. Conclusion The proposed methodology can improve the classification results and at the same time provide a unified biomarker list for further biological examinations and interpretation.

  1. Political Consensus and Fiscal Outcomes

    DEFF Research Database (Denmark)

    Houlberg, Kurt; Holm Pedersen, Lene

    2015-01-01

    It is becoming difficult to maintain consensus in a period of economic austerity, and this possibly challenges the ability of democratic institutions to take decisions on tough economic questions. In order to find out how political consensus influences fiscal outcomes, this article sets out...

  2. Attitude extremity, consensus and diagnosticity

    NARCIS (Netherlands)

    van der Pligt, J.; Ester, P.; van der Linden, J.

    1983-01-01

    Studied the effects of attitude extremity on perceived consensus and willingness to ascribe trait terms to others with either pro- or antinuclear attitudes. 611 Ss rated their attitudes toward nuclear energy on a 5-point scale. Results show that attitude extremity affected consensus estimates. Trait

  3. Main: ANAERO5CONSENSUS [PLACE

    Lifescience Database Archive (English)

    Full Text Available ANAERO5CONSENSUS S000481 05-November-2005 (last modified) kehi One of 16 motifs fou...ty et al., 2005); Arbitrary named ANAERO5CONSENSUS by the PLACEdb curator; See also S000477, S000478, S00047

  4. Main: ANAERO3CONSENSUS [PLACE

    Lifescience Database Archive (English)

    Full Text Available ANAERO3CONSENSUS S000479 05-November-2005 (last modified) kehi One of 16 motifs fou...ty et al., 2005); Arbitrary named ANAERO3CONSENSUS by the PLACEdb curator; See also S000477, S000478, S00048

  5. Main: ANAERO4CONSENSUS [PLACE

    Lifescience Database Archive (English)

    Full Text Available ANAERO4CONSENSUS S000480 05-November-2005 (last modified) kehi One of 16 motifs fou...ty et al., 2005); Arbitrary named ANAERO4CONSENSUS by the PLACEdb curator; See also S000477, S000478, S00047

  6. Main: ANAERO2CONSENSUS [PLACE

    Lifescience Database Archive (English)

    Full Text Available ANAERO2CONSENSUS S000478 05-November-2005 (last modified) kehi One of 16 motifs fou...ty et al., 2005); Arbitrary named ANAERO2CONSENSUS by the PLACEdb curator; See also S000477, S000479, S00048

  7. Main: ANAERO1CONSENSUS [PLACE

    Lifescience Database Archive (English)

    Full Text Available ANAERO1CONSENSUS S000477 05-November-2005 (last modified) kehi One of 16 motifs fou...ty et al., 2005); Arbitrary named ANAERO1CONSENSUS by the PLACEdb curator; See also S000478, S000479, S00048

  8. Mirror averaging with sparsity priors

    CERN Document Server

    Dalalyan, Arnak

    2010-01-01

    We consider the problem of aggregating the elements of a (possibly infinite) dictionary for building a decision procedure, that aims at minimizing a given criterion. Along with the dictionary, an independent identically distributed training sample is available, on which the performance of a given procedure can be tested. In a fairly general set-up, we establish an oracle inequality for the Mirror Averaging aggregate based on any prior distribution. This oracle inequality is applied in the context of sparse coding for different problems of statistics and machine learning such as regression, density estimation and binary classification.

  9. Aggregation and Averaging.

    Science.gov (United States)

    Siegel, Irving H.

    The arithmetic processes of aggregation and averaging are basic to quantitative investigations of employment, unemployment, and related concepts. In explaining these concepts, this report stresses need for accuracy and consistency in measurements, and describes tools for analyzing alternative measures. (BH)

  10. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    1999-01-01

    In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...

  11. Consensus Convolutional Sparse Coding

    KAUST Repository

    Choudhury, Biswarup

    2017-04-11

    Convolutional sparse coding (CSC) is a promising direction for unsupervised learning in computer vision. In contrast to recent supervised methods, CSC allows for convolutional image representations to be learned that are equally useful for high-level vision tasks and low-level image reconstruction and can be applied to a wide range of tasks without problem-specific retraining. Due to their extreme memory requirements, however, existing CSC solvers have so far been limited to low-dimensional problems and datasets using a handful of low-resolution example images at a time. In this paper, we propose a new approach to solving CSC as a consensus optimization problem, which lifts these limitations. By learning CSC features from large-scale image datasets for the first time, we achieve significant quality improvements in a number of imaging tasks. Moreover, the proposed method enables new applications in high dimensional feature learning that has been intractable using existing CSC methods. This is demonstrated for a variety of reconstruction problems across diverse problem domains, including 3D multispectral demosaickingand 4D light field view synthesis.

  12. Between consensus and contestation.

    Science.gov (United States)

    Weale, Albert

    2016-08-15

    Purpose - Noting that discussions of public participation and priority setting typically presuppose certain political theories of democracy, the purpose of this paper is to discuss two theories: the consensual and the agonistic. The distinction is illuminating when considering the difference between institutionalized public participation and contestatory participation. Design/methodology/approach - The approach is a theoretical reconstruction of two ways of thinking about public participation in relation to priority setting in health care, drawing on the work of Habermas, a deliberative theorist, and Mouffe, a theorist of agonism. Findings - The different theoretical approaches can be associated with different ways of understanding priority setting. In particular, agonistic democratic theory would understand priority setting as system of inclusions and exclusions rather than the determination of a consensus of social values, which is the typical deliberative way of thinking about the issues. Originality/value - The paper shows the value of drawing out explicitly the tacit assumptions of practices of political participation in order to reveal their scope and limitations. It suggests that making such theoretical presuppositions explicit has value for health services management in recognizing these implicit choices.

  13. Consensus on consensus: a synthesis of consensus estimates on human-caused global warming

    Science.gov (United States)

    Cook, John; Oreskes, Naomi; Doran, Peter T.; Anderegg, William R. L.; Verheggen, Bart; Maibach, Ed W.; Carlton, J. Stuart; Lewandowsky, Stephan; Skuce, Andrew G.; Green, Sarah A.; Nuccitelli, Dana; Jacobs, Peter; Richardson, Mark; Winkler, Bärbel; Painting, Rob; Rice, Ken

    2016-04-01

    The consensus that humans are causing recent global warming is shared by 90%-100% of publishing climate scientists according to six independent studies by co-authors of this paper. Those results are consistent with the 97% consensus reported by Cook et al (Environ. Res. Lett. 8 024024) based on 11 944 abstracts of research papers, of which 4014 took a position on the cause of recent global warming. A survey of authors of those papers (N = 2412 papers) also supported a 97% consensus. Tol (2016 Environ. Res. Lett. 11 048001) comes to a different conclusion using results from surveys of non-experts such as economic geologists and a self-selected group of those who reject the consensus. We demonstrate that this outcome is not unexpected because the level of consensus correlates with expertise in climate science. At one point, Tol also reduces the apparent consensus by assuming that abstracts that do not explicitly state the cause of global warming (‘no position’) represent non-endorsement, an approach that if applied elsewhere would reject consensus on well-established theories such as plate tectonics. We examine the available studies and conclude that the finding of 97% consensus in published climate research is robust and consistent with other surveys of climate scientists and peer-reviewed studies.

  14. Your Average Nigga

    Science.gov (United States)

    Young, Vershawn Ashanti

    2004-01-01

    "Your Average Nigga" contends that just as exaggerating the differences between black and white language leaves some black speakers, especially those from the ghetto, at an impasse, so exaggerating and reifying the differences between the races leaves blacks in the impossible position of either having to try to be white or forever struggling to…

  15. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    2001-01-01

    In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...

  16. Is There a Consensus on Consensus Methodology? Descriptions and Recommendations for Future Consensus Research.

    Science.gov (United States)

    Waggoner, Jane; Carline, Jan D; Durning, Steven J

    2016-05-01

    The authors of this article reviewed the methodology of three common consensus methods: nominal group process, consensus development panels, and the Delphi technique. The authors set out to determine how a majority of researchers are conducting these studies, how they are analyzing results, and subsequently the manner in which they are reporting their findings. The authors conclude with a set of guidelines and suggestions designed to aid researchers who choose to use the consensus methodology in their work.Overall, researchers need to describe their inclusion criteria. In addition to this, on the basis of the current literature the authors found that a panel size of 5 to 11 members was most beneficial across all consensus methods described. Lastly, the authors agreed that the statistical analyses done in consensus method studies should be as rigorous as possible and that the predetermined definition of consensus must be included in the ultimate manuscript. More specific recommendations are given for each of the three consensus methods described in the article.

  17. UBICACIÓN ÓPTIMA DE RECONECTADORES EN SISTEMAS DE DISTRIBUCIÓN PARA MINIMIZAR LA FRECUENCIA MEDIA DE INTERRUPCIÓN OPTIMAL LOCATION OF RECLOSERS IN DISTRIBUTION NETWORKS IN ORDER TO MINIMIZE THE AVERAGE INTERRUPTION FREQUENCY

    Directory of Open Access Journals (Sweden)

    Jerson Reyes S

    2009-08-01

    Full Text Available En este trabajo se presenta una metodología para minimizar la frecuencia de fallas en Sistemas de Distribución radiales considerando una carga uniformemente distribuida. Se utiliza una aproximación lineal para la ubicación de reconectadores. Este trabajo basa su estudio en la minimización del índice de Frecuencia Media de Interrupción por Potencia instalada, el cual es utilizado como parámetro de regulación y clasificación de las compañías distribuidoras chilenas, según la reglamentación eléctrica vigente. Se introduce además el concepto de Factor de Distancia entre línea Troncal y arranque, el cual puede ser utilizado como herramienta de discriminación para acotar el número de reconectadores a instalar en la línea troncal. Además permite discriminar en base a la data histórica de la línea, si un arranque cualquiera, debe ser evaluado económicamente, como un nuevo alimentador, de forma tal que el índice Frecuencia Media de Interrupción por Potencia instalada sea minimizado.This paper presents a framework for minimizing the average interruption frequency in radial Distribution Systems with uniformly distributed loads. Here, the position of the reclosers has been modeled using a linear approximation. The objective of this paper is to minimize the average interruption frequency per installed power. According to the current electric regulation in Chile, this index is the metric used to regulate and classify the performance of utilities. In the analysis a novel concept of Distance Factor between the main feeder and a branch feeder was introduced. This concept can be utilized as a theoretical limit for the number of switches to install on the main feeder. In addition, based upon the service history of the line, the distance factor determines if a certain line must be economically assessed like a new feeder so that the aforementioned performance index of average interruption frequency per installed power is minimized.

  18. Covariant approximation averaging

    CERN Document Server

    Shintani, Eigo; Blum, Thomas; Izubuchi, Taku; Jung, Chulwoo; Lehner, Christoph

    2014-01-01

    We present a new class of statistical error reduction techniques for Monte-Carlo simulations. Using covariant symmetries, we show that correlation functions can be constructed from inexpensive approximations without introducing any systematic bias in the final result. We introduce a new class of covariant approximation averaging techniques, known as all-mode averaging (AMA), in which the approximation takes account of contributions of all eigenmodes through the inverse of the Dirac operator computed from the conjugate gradient method with a relaxed stopping condition. In this paper we compare the performance and computational cost of our new method with traditional methods using correlation functions and masses of the pion, nucleon, and vector meson in $N_f=2+1$ lattice QCD using domain-wall fermions. This comparison indicates that AMA significantly reduces statistical errors in Monte-Carlo calculations over conventional methods for the same cost.

  19. Dependability in Aggregation by Averaging

    CERN Document Server

    Jesus, Paulo; Almeida, Paulo Sérgio

    2010-01-01

    Aggregation is an important building block of modern distributed applications, allowing the determination of meaningful properties (e.g. network size, total storage capacity, average load, majorities, etc.) that are used to direct the execution of the system. However, the majority of the existing aggregation algorithms exhibit relevant dependability issues, when prospecting their use in real application environments. In this paper, we reveal some dependability issues of aggregation algorithms based on iterative averaging techniques, giving some directions to solve them. This class of algorithms is considered robust (when compared to common tree-based approaches), being independent from the used routing topology and providing an aggregation result at all nodes. However, their robustness is strongly challenged and their correctness often compromised, when changing the assumptions of their working environment to more realistic ones. The correctness of this class of algorithms relies on the maintenance of a funda...

  20. Consensus algorithm in smart grid and communication networks

    Science.gov (United States)

    Alfagee, Husain Abdulaziz

    On a daily basis, consensus theory attracts more and more researches from different areas of interest, to apply its techniques to solve technical problems in a way that is faster, more reliable, and even more precise than ever before. A power system network is one of those fields that consensus theory employs extensively. The use of the consensus algorithm to solve the Economic Dispatch and Load Restoration Problems is a good example. Instead of a conventional central controller, some researchers have explored an algorithm to solve the above mentioned problems, in a distribution manner, using the consensus algorithm, which is based on calculation methods, i.e., non estimation methods, for updating the information consensus matrix. Starting from this point of solving these types of problems mentioned, specifically, in a distribution fashion, using the consensus algorithm, we have implemented a new advanced consensus algorithm. It is based on the adaptive estimation techniques, such as the Gradient Algorithm and the Recursive Least Square Algorithm, to solve the same problems. This advanced work was tested on different case studies that had formerly been explored, as seen in references 5, 7, and 18. Three and five generators, or agents, with different topologies, correspond to the Economic Dispatch Problem and the IEEE 16-Bus power system corresponds to the Load Restoration Problem. In all the cases we have studied, the results met our expectations with extreme accuracy, and completely matched the results of the previous researchers. There is little question that this research proves the capability and dependability of using the consensus algorithm, based on the estimation methods as the Gradient Algorithm and the Recursive Least Square Algorithm to solve such power problems.

  1. Consensus analysis of switching multi-agent systems with fixed topology and time-delay

    Science.gov (United States)

    Pei, Yongquan; Sun, Jitao

    2016-12-01

    This paper investigates the average consensus problems of the discrete-time Markov switching linear multi-agent systems (LMAS) with fixed topology and time-delay. Firstly, we introduce a concept of the average consensus to adapt the stochastic systems. Secondly, a time-delay switching consensus protocol is proposed. By developing a new signal mode, the switching signal of the systems and the time-delay signal of the controller can be merged into one signal. Thirdly, by Lyapunov technique, two LMIs criteria of average consensus are provided, and they reveal that the consensus of the multi-agent systems relates to the spectral radius of the Laplacian matrix. Furthermore, by our results and CCL-type algorithms, we can get the gain matrices. Finally, a numerical example is given to illustrate the efficiency of our results.

  2. Negative Average Preference Utilitarianism

    Directory of Open Access Journals (Sweden)

    Roger Chao

    2012-03-01

    Full Text Available For many philosophers working in the area of Population Ethics, it seems that either they have to confront the Repugnant Conclusion (where they are forced to the conclusion of creating massive amounts of lives barely worth living, or they have to confront the Non-Identity Problem (where no one is seemingly harmed as their existence is dependent on the “harmful” event that took place. To them it seems there is no escape, they either have to face one problem or the other. However, there is a way around this, allowing us to escape the Repugnant Conclusion, by using what I will call Negative Average Preference Utilitarianism (NAPU – which though similar to anti-frustrationism, has some important differences in practice. Current “positive” forms of utilitarianism have struggled to deal with the Repugnant Conclusion, as their theory actually entails this conclusion; however, it seems that a form of Negative Average Preference Utilitarianism (NAPU easily escapes this dilemma (it never even arises within it.

  3. Ocular allergy latin american consensus

    Directory of Open Access Journals (Sweden)

    Myrna Serapião dos Santos

    2011-12-01

    Full Text Available PURPOSE: To establish current definition, classification and staging, and to develop diagnosis and treatment recommendations for ocular allergy, by using Delphi approach. METHODS: Ten Latin American experts on ocular allergy participated in a 4-round Delphi panel approach. Four surveys were constructed and answered by panelists. A two-thirds majority was defined as consensus. Definition, classification, staging and diagnosis and treatment recommendations were the main outcomes. RESULTS: "Ocular allergy" was proposed as the general term to describe ocular allergic diseases. Consensus regarding classification was not reached. Signs and symptoms were considered extremely important for the diagnosis. It was consensus that a staging system should be proposed based on the disease severity. Environmental control, avoidance of allergens and the use of artificial tears were recommended as first line treatment. The secondary treatment should include topical anti-histamines, mast cell stabilizers and multi actions drugs. Topical non-steroidal anti-inflammatory and vasoconstrictors were not recommended. Topical corticosteroids were recommended as third line of treatment for the most severe keratoconjunctivitis. Consensus was not reached regarding the use of systemic corticosteroids or immunosuppressant. Surgical approach and unconventional treatments were not recommended as routine. CONCLUSION: The task of creating guidelines for ocular allergies showed to be very complex. Many controversial topics remain unsolved. A larger consensus including experts from different groups around the world may be needed to further improve the current recommendations for several aspects of ocular allergy.

  4. Cluster consensus of high-order multi-agent systems with switching topologies

    Science.gov (United States)

    Hou, Bo; Sun, Fuchun; Li, Hongbo; Chen, Yao; Xi, Jianxiang

    2016-09-01

    This paper investigates the cluster consensus problems of generic linear multi-agent systems with switching topologies. Sufficient criteria for cluster consensus, which generalise the results in existing literatures, are derived for both state feedback and observer-based control schemes. By using an averaging method, it is shown that cluster consensus can be achieved when the union of the acyclic topologies contains a directed spanning tree within each cluster frequently enough. We also provide a principle to construct digraphs with inter-cluster cyclic couplings that promote cluster consensus regardless of the magnitude of inter-agent coupling weights. Finally, numerical examples are given to demonstrate the effectiveness of the proposed approaches.

  5. Consensus of High-Order Nonlinear Multiagent Systems with Constrained Switching Topologies

    Directory of Open Access Journals (Sweden)

    Junwei Wang

    2017-01-01

    Full Text Available The relationship between control and communication constraints is becoming of central importance in the consensus problem of networked agents. In this paper, we investigate such a problem for nonlinear multiagent systems with Lipschitz dynamics. To reflect communication constraints, the topology is assumed to switch within a finite set of digraphs characterised by an average dwell time switching signal. By constructing a suitable multiple Lyapunov function, we show that consensus can be reached under the designed consensus protocol. A multistep algorithm for designing consensus protocol is then developed by solving the Lyapunov equation and algebraic Riccati equation. Finally, simulation examples are delineated to substantiate the effectiveness of the proposed algorithms.

  6. Consensus clustering in complex networks

    CERN Document Server

    Lancichinetti, Andrea; 10.1038/srep00336

    2012-01-01

    The community structure of complex networks reveals both their organization and hidden relationships among their constituents. Most community detection methods currently available are not deterministic, and their results typically depend on the specific random seeds, initial conditions and tie-break rules adopted for their execution. Consensus clustering is used in data analysis to generate stable results out of a set of partitions delivered by stochastic methods. Here we show that consensus clustering can be combined with any existing method in a self-consistent way, enhancing considerably both the stability and the accuracy of the resulting partitions. This framework is also particularly suitable to monitor the evolution of community structure in temporal networks. An application of consensus clustering to a large citation network of physics papers demonstrates its capability to keep track of the birth, death and diversification of topics.

  7. Tree Codes Improve Convergence Rate of Consensus Over Erasure Channels

    CERN Document Server

    Sukhavasi, Ravi Teja

    2012-01-01

    We study the problem of achieving average consensus between a group of agents over a network with erasure links. In the context of consensus problems, the unreliability of communication links between nodes has been traditionally modeled by allowing the underlying graph to vary with time. In other words, depending on the realization of the link erasures, the underlying graph at each time instant is assumed to be a subgraph of the original graph. Implicit in this model is the assumption that the erasures are symmetric: if at time t the packet from node i to node j is dropped, the same is true for the packet transmitted from node j to node i. However, in practical wireless communication systems this assumption is unreasonable and, due to the lack of symmetry, standard averaging protocols cannot guarantee that the network will reach consensus to the true average. In this paper we explore the use of channel coding to improve the performance of consensus algorithms. For symmetric erasures, we show that, for certain...

  8. The Copenhagen Consensus Conference 2016

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Krustrup, Peter; Duda, Joan

    2016-01-01

    on the effects of physical activity on children’s and youth’s fitness, health, cognitive functioning, engagement, motivation, psychological well-being and social inclusion, as well as presenting educational and physical activity implementation strategies. The consensus was obtained through an iterative process......From 4 to 7 April 2016, 24 researchers from 8 countries and from a variety of academic disciplines gathered in Snekkersten, Denmark, to reach evidence-based consensus about physical activity in children and youth, that is, individuals between 6 and 18 years. Physical activity is an overarching term...

  9. C3 glomerulopathy: consensus report

    Science.gov (United States)

    Pickering, Matthew C; D'Agati, Vivette D; Nester, Carla M; Smith, Richard J; Haas, Mark; Appel, Gerald B; Alpers, Charles E; Bajema, Ingeborg M; Bedrosian, Camille; Braun, Michael; Doyle, Mittie; Fakhouri, Fadi; Fervenza, Fernando C; Fogo, Agnes B; Frémeaux-Bacchi, Véronique; Gale, Daniel P; Goicoechea de Jorge, Elena; Griffin, Gene; Harris, Claire L; Holers, V Michael; Johnson, Sally; Lavin, Peter J; Medjeral-Thomas, Nicholas; Paul Morgan, B; Nast, Cynthia C; Noel, Laure-Hélène; Peters, D Keith; Rodríguez de Córdoba, Santiago; Servais, Aude; Sethi, Sanjeev; Song, Wen-Chao; Tamburini, Paul; Thurman, Joshua M; Zavros, Michael; Cook, H Terence

    2013-01-01

    C3 glomerulopathy is a recently introduced pathological entity whose original definition was glomerular pathology characterized by C3 accumulation with absent or scanty immunoglobulin deposition. In August 2012, an invited group of experts (comprising the authors of this document) in renal pathology, nephrology, complement biology, and complement therapeutics met to discuss C3 glomerulopathy in the first C3 Glomerulopathy Meeting. The objectives were to reach a consensus on: the definition of C3 glomerulopathy, appropriate complement investigations that should be performed in these patients, and how complement therapeutics should be explored in the condition. This meeting report represents the current consensus view of the group. PMID:24172683

  10. Febrile Seizures: Controversy and Consensus

    Science.gov (United States)

    Doiron, Omer A.

    1983-01-01

    Although febrile convulsions are a relatively common complaint, the approach to their management is far from uniform and highly controversial. This article reviews the consensus statement on febrile convulsions arrived at by the Consensus Development Conference held in 1980 by the National Institutes of Health, together with other literature of interest to family physicians. Guidelines are given for the assessment, diagnosis and emergency treatment of febrile seizures. Epilepsy and atypical febrile convulsions are distinguished from simple febrile seizures. Prognosis, prevention, and the importance of counselling parents are discussed, as well as the controversial issue of prophylactic treatment. PMID:21286583

  11. The Copenhagen Consensus Conference 2016

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Krustrup, Peter; Duda, Joan;

    2016-01-01

    that consists of many structured and unstructured forms within school and out-of-school-time contexts, including organised sport, physical education, outdoor recreation, motor skill development programmes, recess, and active transportation such as biking and walking. This consensus statement presents the accord...

  12. Balancing multiple roles through consensus

    DEFF Research Database (Denmark)

    Oshima, Sae

    2014-01-01

    This study demonstrates how participants in haircutting sessions merge different roles during one of the most sensitive moments of an encounter: requesting and/or making revisions to a new cut. During the process of arriving at a consensus of whether or not changes need to be made to the new cut...

  13. Graph- versus Vector-Based Analysis of a Consensus Protocol

    NARCIS (Netherlands)

    Delzanno, Giorgio; Rensink, Arend; Traverso, Riccardo; Bošnački, Dragan; Edelkamp, Stefan; Lluch Lafuente, Alberto; Wijs, Anton

    2014-01-01

    The Paxos distributed consensus algorithm is a challenging case-study for standard, vector-based model checking techniques. Due to asynchronous communication, exhaustive analysis may generate very large state spaces already for small model instances. In this paper, we show the advantages of graph tr

  14. Consensus of Heterogeneous Linear Multiagent Systems With Communication Time-Delays.

    Science.gov (United States)

    Xu, Xiang; Liu, Lu; Feng, Gang

    2017-05-23

    This paper studies the consensus problem of heterogeneous linear multiagent systems with arbitrarily large constant, time-varying, or distributed communication delays. Novel distributed dynamic controllers are proposed for such multiagent systems with fixed and switching directed communication topologies, respectively. It is shown that the controlled heterogeneous linear multiagent system can reach consensus for arbitrarily large constant, time-varying, and distributed communication delays under some sufficient conditions. Simulation examples are provided to demonstrate the effectiveness of the proposed controllers.

  15. Optimal Network Design for Consensus Formation: Wisdom of Networked Agents

    Directory of Open Access Journals (Sweden)

    Eugene S. Kitamura

    2014-08-01

    Full Text Available The wisdom of crowds refers to the phenomenon in which the collective knowledge of a community is greater than the knowledge of any individual. This paper proposes a network design for the fastest and slowest consensus formation under average node degree restrictions, which is one aspect of the wisdom of crowds concept. Consensus and synchronization problems are closely related to variety of issues such as collective behavior in nature, the interaction among agents as a matter of the robot control, and building efficient wireless sensor networks. However, designing networks with desirable properties is complex and it may pose a multi-constraint and multi-criterion optimization problem. For the purpose of realizing such efficient network topology, this paper presents an optimization approach to design networks for better consensus formation by focusing on the eigenvalue spectral of Laplacian matrix. In both the fastest and slowest networks presented, consensus is formed among local structures first, then on a global scale. This suggests that both local and global topology influence the networks dynamics. These findings are useful for those who seek to manage efficient consensus and synchronization in a setting that can be modeled as a multi-agent system.

  16. Distributed attitude consensus for multiple rigid body systems with communication delay and jointly connected topologies%通信时延和联合连通拓扑下多刚体系统分布式姿态一致性控制

    Institute of Scientific and Technical Information of China (English)

    马龙; 王仕成; 闵海波; 郭扬

    2016-01-01

    本文研究了通信时延和联合连通切换拓扑条件下的多刚体系统分布式姿态一致性控制问题。通过构建有效的辅助向量并选择合适的Lyapunov-Krasovskii函数,分别对恒定通信时延和时变通信时延两种不同情况下的控制器进行了设计。数值仿真结果表明,本文提出的方法能够有效地解决这类分布式姿态一致性控制问题。%In this paper, we study the distributed attitude consensus problem for multiple networked rigid body systems in the case of communication time-delays together with jointly connected switching topologies. By constructing useful aux-iliary vectors and choosing proper common Lyapunov-Krasovskii functions, we design two control laws for two different cases respectively, i.e., the case with constant communication time-delays, and the case with time varying communication time-delays. Numerical simulation shows that the proposed algorithms are effective to this kind of distributed attitude consensus problem.

  17. Does Having More Options Mean Harder to Reach Consensus?

    CERN Document Server

    Wu, Degang

    2016-01-01

    We generalize a binary majority-vote model on adaptive networks to a plurality-vote counterpart. When opinions are uniformly distributed in the population of voters in the initial state, it is found that having more available opinions in the initial state actually accelerate the time to consensus. In particular, we investigate the three-state plurality-vote model. While time to consensus in two state model scales exponentially with population size $N$, for finite-size system, there is a non-zero probability that either the population reaches the consensus state in a time that is very short and independent of $N$ (in the heterophily regime), or in a time that scales exponentially with $N$ but is still much faster than two-state model.

  18. Energy strategy: Roadmap to consensus

    Energy Technology Data Exchange (ETDEWEB)

    1990-11-01

    The United States lacks a comprehensive approach to policy-making in the energy realm. Today, as in the past, individual constituency groups tend to focus on their particular aspect of the energy challenge. Many employ a decide-announce-defend'' approach to policy-making, setting out to secure a unilateral advantage for themselves. By so doing, they inevitably pit interest against interest. The result is a polarization of constituencies, and shortsighted policies designed to address the issue of the moment. The American Energy Assurance Council (AEAC) is a non-profit organization founded in 1987 for the sole purpose of facilitating progress toward a fair efficient wise, stable, and consensus-based national energy strategy. AEAC does not have a substantive policy agencies. Rather, we are committed to supporting a process whereby the many stakeholders and policy makers concerned with energy-related issues can come together in productive discourse, thereby overcoming ignorance of each other's positions. The Council seeks to act as a facilitative body, providing a safe'' context for inventive and creative thinking. We attempt to build a store of common knowledge, and to build on that store according to mutually agreed-upon groundrules, and employing sophisticated approaches to facilitation and mediation. This report, the National Energy Consensus Experiment (NECE), was an ambitious experiment in consensus-building. We learned a great deal from it, both in terms of substance and process, and we are convinced that it holds important lessons for others who may seek to build consensus in the public policy realm.

  19. Energy strategy: Roadmap to consensus

    Energy Technology Data Exchange (ETDEWEB)

    1990-11-01

    The United States lacks a comprehensive approach to policy-making in the energy realm. Today, as in the past, individual constituency groups tend to focus on their particular aspect of the energy challenge. Many employ a ``decide-announce-defend`` approach to policy-making, setting out to secure a unilateral advantage for themselves. By so doing, they inevitably pit interest against interest. The result is a polarization of constituencies, and shortsighted policies designed to address the issue of the moment. The American Energy Assurance Council (AEAC) is a non-profit organization founded in 1987 for the sole purpose of facilitating progress toward a fair efficient wise, stable, and consensus-based national energy strategy. AEAC does not have a substantive policy agencies. Rather, we are committed to supporting a process whereby the many stakeholders and policy makers concerned with energy-related issues can come together in productive discourse, thereby overcoming ignorance of each other`s positions. The Council seeks to act as a facilitative body, providing a ``safe`` context for inventive and creative thinking. We attempt to build a store of common knowledge, and to build on that store according to mutually agreed-upon groundrules, and employing sophisticated approaches to facilitation and mediation. This report, the National Energy Consensus Experiment (NECE), was an ambitious experiment in consensus-building. We learned a great deal from it, both in terms of substance and process, and we are convinced that it holds important lessons for others who may seek to build consensus in the public policy realm.

  20. Coordination control of distributed systems

    CERN Document Server

    Villa, Tiziano

    2015-01-01

    This book describes how control of distributed systems can be advanced by an integration of control, communication, and computation. The global control objectives are met by judicious combinations of local and nonlocal observations taking advantage of various forms of communication exchanges between distributed controllers. Control architectures are considered according to  increasing degrees of cooperation of local controllers:  fully distributed or decentralized control,  control with communication between controllers,  coordination control, and multilevel control.  The book covers also topics bridging computer science, communication, and control, like communication for control of networks, average consensus for distributed systems, and modeling and verification of discrete and of hybrid systems. Examples and case studies are introduced in the first part of the text and developed throughout the book. They include: control of underwater vehicles, automated-guided vehicles on a container terminal, contro...

  1. Using Network Dynamical Influence to Drive Consensus

    Science.gov (United States)

    Punzo, Giuliano; Young, George F.; MacDonald, Malcolm; Leonard, Naomi E.

    2016-05-01

    Consensus and decision-making are often analysed in the context of networks, with many studies focusing attention on ranking the nodes of a network depending on their relative importance to information routing. Dynamical influence ranks the nodes with respect to their ability to influence the evolution of the associated network dynamical system. In this study it is shown that dynamical influence not only ranks the nodes, but also provides a naturally optimised distribution of effort to steer a network from one state to another. An example is provided where the “steering” refers to the physical change in velocity of self-propelled agents interacting through a network. Distinct from other works on this subject, this study looks at directed and hence more general graphs. The findings are presented with a theoretical angle, without targeting particular applications or networked systems; however, the framework and results offer parallels with biological flocks and swarms and opportunities for design of technological networks.

  2. Dose calculation formalisms and consensus dosimetry parameters for intravascular brachytherapy dosimetry: recommendations of the AAPM Therapy Physics Committee Task Group No. 149.

    Science.gov (United States)

    Chiu-Tsao, Sou-Tung; Schaart, Dennis R; Soares, Christopher G; Nath, Ravinder

    2007-11-01

    Since the publication of AAPM Task Group 60 report in 1999, a considerable amount of dosimetry data for the three coronary brachytherapy systems in use in the United States has been reported. A subgroup, Task Group 149, of the AAPM working group on Special Brachytherapy Modalities (Bruce Thomadsen, Chair) was charged to develop recommendations for dose calculation formalisms and the related consensus dosimetry parameters. The recommendations of this group are presented here. For the Cordis 192Ir and Novoste 90Sr/90Y systems, the original TG-43 formalism in spherical coordinates should be used along with the consensus values of the dose rate constant, geometry function, radial dose function, and anisotropy function for the single seeds. Contributions from the single seeds should be added linearly for the calculation of dose distributions from a source train. For the Guidant 32P wire system, the modified TG-43 formalism in cylindrical coordinates along with the recommended data for the 20 and 27 mm wires should be used. Data tables for the 6, 10, 14, 18, and 22 seed trains of the Cordis system, 30, 40, and 60 mm seed trains of the Novoste system, and the 20 and 27 mm wires of the Guidant system are presented along with our rationale and methodology for selecting the consensus data. Briefly, all available datasets were compared with each other and the consensus dataset was either an average of available data or the one obtained from the most densely populated study; in most cases this was a Monte Carlo calculation.

  3. Physical Theories with Average Symmetry

    OpenAIRE

    Alamino, Roberto C.

    2013-01-01

    This Letter probes the existence of physical laws invariant only in average when subjected to some transformation. The concept of a symmetry transformation is broadened to include corruption by random noise and average symmetry is introduced by considering functions which are invariant only in average under these transformations. It is then shown that actions with average symmetry obey a modified version of Noether's Theorem with dissipative currents. The relation of this with possible violat...

  4. Consensus Strategies for Signed Profiles on Graphs

    NARCIS (Netherlands)

    K. Balakrishnan (Kannan); M. Changat (Manoj); H.M. Mulder (Martyn); A.R. Subhamathi (Ajitha)

    2011-01-01

    textabstractThe median problem is a classical problem in Location Theory: one searches for a location that minimizes the average distance to the sites of the clients. This is for desired facilities as a distribution center for a set of warehouses. More recently, for obnoxious facilities, the

  5. Average Convexity in Communication Situations

    NARCIS (Netherlands)

    Slikker, M.

    1998-01-01

    In this paper we study inheritance properties of average convexity in communication situations. We show that the underlying graph ensures that the graphrestricted game originating from an average convex game is average convex if and only if every subgraph associated with a component of the underlyin

  6. Identification of consensus biomarkers for predicting non-genotoxic hepatocarcinogens

    Science.gov (United States)

    Huang, Shan-Han; Tung, Chun-Wei

    2017-01-01

    The assessment of non-genotoxic hepatocarcinogens (NGHCs) is currently relying on two-year rodent bioassays. Toxicogenomics biomarkers provide a potential alternative method for the prioritization of NGHCs that could be useful for risk assessment. However, previous studies using inconsistently classified chemicals as the training set and a single microarray dataset concluded no consensus biomarkers. In this study, 4 consensus biomarkers of A2m, Ca3, Cxcl1, and Cyp8b1 were identified from four large-scale microarray datasets of the one-day single maximum tolerated dose and a large set of chemicals without inconsistent classifications. Machine learning techniques were subsequently applied to develop prediction models for NGHCs. The final bagging decision tree models were constructed with an average AUC performance of 0.803 for an independent test. A set of 16 chemicals with controversial classifications were reclassified according to the consensus biomarkers. The developed prediction models and identified consensus biomarkers are expected to be potential alternative methods for prioritization of NGHCs for further experimental validation.

  7. Bayesian Averaging is Well-Temperated

    DEFF Research Database (Denmark)

    Hansen, Lars Kai

    2000-01-01

    Bayesian predictions are stochastic just like predictions of any other inference scheme that generalize from a finite sample. While a simple variational argument shows that Bayes averaging is generalization optimal given that the prior matches the teacher parameter distribution the situation...

  8. Generalized Jackknife Estimators of Weighted Average Derivatives

    DEFF Research Database (Denmark)

    Cattaneo, Matias D.; Crump, Richard K.; Jansson, Michael

    With the aim of improving the quality of asymptotic distributional approximations for nonlinear functionals of nonparametric estimators, this paper revisits the large-sample properties of an important member of that class, namely a kernel-based weighted average derivative estimator. Asymptotic li...

  9. Sampling Based Average Classifier Fusion

    Directory of Open Access Journals (Sweden)

    Jian Hou

    2014-01-01

    fusion algorithms have been proposed in literature, average fusion is almost always selected as the baseline for comparison. Little is done on exploring the potential of average fusion and proposing a better baseline. In this paper we empirically investigate the behavior of soft labels and classifiers in average fusion. As a result, we find that; by proper sampling of soft labels and classifiers, the average fusion performance can be evidently improved. This result presents sampling based average fusion as a better baseline; that is, a newly proposed classifier fusion algorithm should at least perform better than this baseline in order to demonstrate its effectiveness.

  10. Research methods for formal consensus development.

    Science.gov (United States)

    James, Daphne; Warren-Forward, Helen

    2015-01-01

    This paper reviews three research methods for developing consensus. Consensus statements and guidelines are increasingly used to clarify and standardise practice, and inform health policy, when relevant and rigorous evidence is lacking. Clinicians need to evaluate the quality of practice guidelines to determine whether to incorporate them into clinical practice or reject them. Formal methods of developing consensus provide a scientific method that uses expert panel members to evaluate current evidence and expert opinions to produce consensus statements for clinical problems. Online search for relevant literature was conducted in Medline and CINAHL. A literature review of consensus, consensus development and research methods papers published in English in peer-reviewed journals. The three methods of developing consensus discussed are the Delphi technique, nominal group technique and the consensus development conference. The techniques and their respective advantages are described, and examples from the literature are provided. The three methods are compared and a flowchart to assist researchers selecting an appropriate method is included. Online resources with information on the development and evaluation of clinical guidelines are reviewed. This paper will help researchers to select an appropriate research method for developing consensus statements and guidelines. When developing consensus guidelines for clinical practice, researchers should use a formal research method to ensure rigour and credibility.

  11. Improving consensus contact prediction via server correlation reduction

    Directory of Open Access Journals (Sweden)

    Xu Jinbo

    2009-05-01

    Full Text Available Abstract Background Protein inter-residue contacts play a crucial role in the determination and prediction of protein structures. Previous studies on contact prediction indicate that although template-based consensus methods outperform sequence-based methods on targets with typical templates, such consensus methods perform poorly on new fold targets. However, we find out that even for new fold targets, the models generated by threading programs can contain many true contacts. The challenge is how to identify them. Results In this paper, we develop an integer linear programming model for consensus contact prediction. In contrast to the simple majority voting method assuming that all the individual servers are equally important and independent, the newly developed method evaluates their correlation by using maximum likelihood estimation and extracts independent latent servers from them by using principal component analysis. An integer linear programming method is then applied to assign a weight to each latent server to maximize the difference between true contacts and false ones. The proposed method is tested on the CASP7 data set. If the top L/5 predicted contacts are evaluated where L is the protein size, the average accuracy is 73%, which is much higher than that of any previously reported study. Moreover, if only the 15 new fold CASP7 targets are considered, our method achieves an average accuracy of 37%, which is much better than that of the majority voting method, SVM-LOMETS, SVM-SEQ, and SAM-T06. These methods demonstrate an average accuracy of 13.0%, 10.8%, 25.8% and 21.2%, respectively. Conclusion Reducing server correlation and optimally combining independent latent servers show a significant improvement over the traditional consensus methods. This approach can hopefully provide a powerful tool for protein structure refinement and prediction use.

  12. Relationship between Trust and Social Consensus among Citizens of 20 Years Old and Above in Gonbadekavoos

    Directory of Open Access Journals (Sweden)

    Gholamreza Khoshfar

    2014-05-01

    The results of the descriptive findings shows that social consensus average is 3.07 in a 0-5 scale, which means it is average to up, and trust average is 2.70, a little bit below the average point (3. Different dimensions of trust, including personal, generalized and institutional each have the averages of 3.20, 2.10 and 2.89 respectively, and the average for mediating variable, national identity, is 3.53. 59% of the sample are men and 70% of them are in the age group of 20-39 years old. More than two third of the sample are born in city areas and about 75% them are married. More than two third of the participants are working and about 68% of them own a house. About 43% of the sample are Fars, about 41% are Turkmen and the rest are Turk (9/1%, Sistani (2/9%, Baluch (1/8 % and 1/5% belonged to other ethnic backgrounds. The analysis indicates that there is a significant relationship between trust and social consensus and this is a moderate relationship (R=0/41. With regard to the amount of k-Square coefficient, the trust variable can predict about 17% of the changes of the dependent variable, social consensus. Institutional trust has the most impact alone on social consensus. It alone predicted 17% of the changes of social consensus and generalized trust explained only 0/7% of these changes. National identity as a mediating variable predicted about 40% of the changes of social consensus. The results of multiple regression analysis shows that a moderate correlation (R2=0/248 exists between independent and dependent variables. The results showed that relationship between trust and social consensus among the Fars is stronger compared to other ethnic groups.

  13. Output Consensus of Heterogeneous Linear Discrete-Time Multiagent Systems With Structural Uncertainties.

    Science.gov (United States)

    Li, Shaobao; Feng, Gang; Luo, Xiaoyuan; Guan, Xinping

    2015-12-01

    This paper investigates the output consensus problem of heterogeneous discrete-time multiagent systems with individual agents subject to structural uncertainties and different disturbances. A novel distributed control law based on internal reference models is first presented for output consensus of heterogeneous discrete-time multiagent systems without structural uncertainties, where internal reference models embedded in controllers are designed with the objective of reducing communication costs. Then based on the distributed internal reference models and the well-known internal model principle, a distributed control law is further presented for output consensus of heterogeneous discrete-time multiagent systems with structural uncertainties. It is shown in both cases that the consensus trajectory of the internal reference models determines the output trajectories of agents. Finally, numerical simulation results are provided to illustrate the effectiveness of the proposed control schemes.

  14. Decentralised consensus for multiple Lagrangian systems based on event-triggered strategy

    Science.gov (United States)

    Liu, Xiangdong; Du, Changkun; Lu, Pingli; Yang, Dapeng

    2016-06-01

    This paper considers the decentralised event-triggered consensus problem for multi-agent systems with Lagrangian dynamics under undirected graphs. First, a distributed, leaderless, and event-triggered consensus control algorithm is presented based on the definition of generalised positions and velocities for all agents. There is only one triggering function for both the generalised positions and velocities and no Zeno behaviour exhibited under the proposed consensus strategy. Second, an adaptive event-triggered consensus control algorithm is proposed for such multi-agent systems with unknown constant parameters. Third, based on sliding-mode method, an event-triggered consensus control algorithm is considered for the case with external disturbance. Finally, simulation results are given to illustrate the theoretical results.

  15. Learning gene regulatory networks from gene expression data using weighted consensus

    KAUST Repository

    Fujii, Chisato

    2016-08-25

    An accurate determination of the network structure of gene regulatory systems from high-throughput gene expression data is an essential yet challenging step in studying how the expression of endogenous genes is controlled through a complex interaction of gene products and DNA. While numerous methods have been proposed to infer the structure of gene regulatory networks, none of them seem to work consistently over different data sets with high accuracy. A recent study to compare gene network inference methods showed that an average-ranking-based consensus method consistently performs well under various settings. Here, we propose a linear programming-based consensus method for the inference of gene regulatory networks. Unlike the average-ranking-based one, which treats the contribution of each individual method equally, our new consensus method assigns a weight to each method based on its credibility. As a case study, we applied the proposed consensus method on synthetic and real microarray data sets, and compared its performance to that of the average-ranking-based consensus and individual inference methods. Our results show that our weighted consensus method achieves superior performance over the unweighted one, suggesting that assigning weights to different individual methods rather than giving them equal weights improves the accuracy. © 2016 Elsevier B.V.

  16. Consensus of a class of discrete-time nonlinear multi-agent systems in the presence of communication delays.

    Science.gov (United States)

    Hu, Haiyun; Lin, Zongli

    2017-02-01

    In this paper, we study the consensus problem for a class of discrete-time nonlinear multi-agent systems. The dynamics of each agent is input affine and the agents are connected through a connected undirected communication network. Distributed control laws are proposed and consensus analysis is conducted both in the absence and in the presence of communication delays. Both theoretical analysis and numerical simulation show that our control laws ensure state consensus of the multi-agent system.

  17. Physical Theories with Average Symmetry

    CERN Document Server

    Alamino, Roberto C

    2013-01-01

    This Letter probes the existence of physical laws invariant only in average when subjected to some transformation. The concept of a symmetry transformation is broadened to include corruption by random noise and average symmetry is introduced by considering functions which are invariant only in average under these transformations. It is then shown that actions with average symmetry obey a modified version of Noether's Theorem with dissipative currents. The relation of this with possible violations of physical symmetries, as for instance Lorentz invariance in some quantum gravity theories, is briefly commented.

  18. Consensus of Hybrid Multi-Agent Systems.

    Science.gov (United States)

    Zheng, Yuanshi; Ma, Jingying; Wang, Long

    2017-01-27

    In this brief, we consider the consensus problem of hybrid multiagent systems. First, the hybrid multiagent system is proposed, which is composed of continuous-time and discrete-time dynamic agents. Then, three kinds of consensus protocols are presented for the hybrid multiagent system. The analysis tool developed in this brief is based on the matrix theory and graph theory. With different restrictions of the sampling period, some necessary and sufficient conditions are established for solving the consensus of the hybrid multiagent system. The consensus states are also obtained under different protocols. Finally, simulation examples are provided to demonstrate the effectiveness of our theoretical results.

  19. Theories about consensus-based conservation.

    Science.gov (United States)

    Leach, William D

    2006-04-01

    "Conservation and the Myth of Consensus" (Peterson et al. 2005) levels several serious indictments against consensus-based approaches to environmental decision making. Namely, the authors argue that consensus processes (1) reinforce apathy and ignorance of conservation issues; (2) legitimize damage to the environment; (3) quash public debate about conservation; (4) solidify the existing balance of power in favor of prodevelopment forces; and (5) block progress toward an ecologically sustainable future. Careful scrutiny of consensus-based approaches is important, especially considering their surging use in conservation policy. In the spirit of advancing the debate further, I review some of the limitations of the essay and its modes of inquiry.

  20. National consensus on the management of constipation in indonesia 2010.

    Science.gov (United States)

    2011-10-01

    Constipation is a common complaint in our daily practice, which may occur in young adult or elderly patients. Recently, the incidence has been increasing; however, most patients try to have self-medication using over-the-counter (OTC) drugs, which is usually inappropriate. Moreover, there has been unequal distribution of knowledge and vigilance of medical practitioners, both general physician and specialist doctors on the constipation issue. Therefore, patients usually present with greater complications. The Organizing Committee of Indonesian Society of Gastroenterology or Pengurus Besar Perkumpulan Gastroenterologi Indonesia (PB PGI) considers that it is important to compose a National Consensus on the Management of Constipation in Indonesia. The Consensus is expected to be a guideline for doctors to deal with patients who have constipation in their daily practice, so that optimal results could be achieved. Nowadays, there are new data on definition, pathophysiology, diagnosis and management of constipation; thus, the Organizing Committee of ISG feels that it is necessary to revise the established consensus. We expect that the consensus may bring advantages for medical practitioners in Indonesia and in general, it may cause community health improvement.

  1. Subclinical hypothyroidism: Controversies to consensus

    Directory of Open Access Journals (Sweden)

    Syed Abbas Raza

    2013-01-01

    Full Text Available Diagnoses of subclinicaal hypothyroidism (SCH is biochemically made, when serum thyroid stimulating hormone (TSH levels is elevated while free thyroid hormone levels are within normal reference range. SCH is diagnosed after excluding all other causes of elevated TSH levels. Symptoms of SCH may vary from being asymptomatic to having mild nonspecific symptoms. The risk of progression to overt hypothyroidism is related to number of factors including initial serum TSH concentration, presence of auto antibodies, family history and presence goiter. Various screening recommendations for thyroid function assessment are in practice. There are still controversies surrounding SCH and associated risk of various cardiovascular diseases (CVDs, pregnancy outcomes, neuropsychiatric issues, metabolic syndrome, and dyslipidemia. Consensus will require more large randomized clinical studies involving various age groups and medical condition, especially in developing countries. All these efforts will definitely improve our understanding of disease and ultimately patient outcomes.

  2. Humanitarian war: a new consensus?

    Science.gov (United States)

    Woodward, S L

    2001-12-01

    The NATO bombing operation Allied Force against Yugoslavia in March-June 1999 represents the final disappearance of the narrowing divide between humanitarianism and politics: a war initiated and justified on humanitarian grounds. Although unlikely to be repeated any time soon, the Kosovo case appears to have cemented an ideological shift on the international right and even necessity of sing military force to protect civilians within sovereign states. Rather than humanitarians acknowledging the political context and consequences of their work, however, the case suggests the embrace of humanitarian principles of universality and neutrality by military organisations. This article discusses some consequences of the new consensus: neglect of the political context (both local and foreign) of such operations, interaction between the operational dynamics of relief operations and the logic of war and the political consequences of using the humanitarian legitimation and mission in such cases.

  3. International Consensus on drug allergy.

    Science.gov (United States)

    Demoly, P; Adkinson, N F; Brockow, K; Castells, M; Chiriac, A M; Greenberger, P A; Khan, D A; Lang, D M; Park, H-S; Pichler, W; Sanchez-Borges, M; Shiohara, T; Thong, B Y- H

    2014-04-01

    When drug reactions resembling allergy occur, they are called drug hypersensitivity reactions (DHRs) before showing the evidence of either drug-specific antibodies or T cells. DHRs may be allergic or nonallergic in nature, with drug allergies being immunologically mediated DHRs. These reactions are typically unpredictable. They can be life-threatening, may require or prolong hospitalization, and may necessitate changes in subsequent therapy. Both underdiagnosis (due to under-reporting) and overdiagnosis (due to an overuse of the term ‘allergy’) are common. A definitive diagnosis of such reactions is required in order to institute adequate treatment options and proper preventive measures. Misclassification based solely on the DHR history without further testing may affect treatment options, result in adverse consequences, and lead to the use of more-expensive or less-effective drugs, in contrast to patients who had undergone a complete drug allergy workup. Several guidelines and/or consensus documents on general or specific drug class-induced DHRs are available to support the medical decision process. The use of standardized systematic approaches for the diagnosis and management of DHRs carries the potential to improve outcomes and should thus be disseminated and implemented. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), formed by the European Academy of Allergy and Clinical Immunology (EAACI), the American Academy of Allergy, Asthma and Immunology (AAAAI), the American College of Allergy, Asthma and Immunology (ACAAI), and the World Allergy Organization (WAO), has decided to issue an International CONsensus (ICON) on drug allergy. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences and deficiencies of evidence, thus providing a comprehensive reference document for the diagnosis and management of

  4. Rectal cancer radiotherapy: Towards European consensus

    Energy Technology Data Exchange (ETDEWEB)

    Valentini, Vincenzo (Cattedra di Radioterapia, Univ. Cattolica S.Cuore, Rome (Italy)), E-mail: vvalentini@rm.unicatt.it; Glimelius, Bengt (Dept. of Oncology, Radiology and Clinical Immunology, Uppsala Univ., Uppsala (Sweden))

    2010-11-15

    Background and purpose. During the first decade of the 21st century several important European randomized studies in rectal cancer have been published. In order to help shape clinical practice based on best scientific evidence, the International Conference on 'Multidisciplinary Rectal Cancer Treatment: Looking for an European Consensus' (EURECA-CC2) was organized. This article summarizes the consensus about imaging and radiotherapy of rectal cancer and gives an update until May 2010. Methods. Consensus was achieved using the Delphi method. Eight chapters were identified: epidemiology, diagnostics, pathology, surgery, radiotherapy and chemotherapy, treatment toxicity and quality of life, follow-up, and research questions. Each chapter was subdivided by topic, and a series of statements were developed. Each committee member commented and voted, sentence by sentence three times. Sentences which did not reach agreement after voting round no 2 were openly debated during the Conference in Perugia (Italy) December 2008. The Executive Committee scored percentage consensus based on three categories: 'large consensus', 'moderate consensus', 'minimum consensus'. Results. The total number of the voted sentences was 207. Of the 207, 86% achieved large consensus, 13% achieved moderate consensus, and only three (1%) resulted in minimum consensus. No statement was disagreed by more than 50% of members. All chapters were voted on by at least 75% of the members, and the majority was voted on by >85%. Considerable progress has been made in staging and treatment, including radiation treatment of rectal cancer. Conclusions. This Consensus Conference represents an expertise opinion process that may help shape future programs, investigational protocols, and guidelines for staging and treatment of rectal cancer throughout Europe. In spite of substantial progress, many research challenges remain

  5. Strategic consensus mapping : A new method for testing and visualizing strategic consensus within and between teams

    NARCIS (Netherlands)

    Tarakci, M.; Ates, N.Y.; Porck, J.P.; van Knippenberg, D.; Groenen, P.J.F.; de Haas, M.

    2014-01-01

    Research on strategic consensus focuses primarily on the extent of agreement among team members regarding organizational strategy. It does not include elements such as the content of the agreement, between-group consensus, or the significance of differences in consensus (e.g., for evaluating the eff

  6. Consensus of Multiagent Systems Subject to Partially Accessible and Overlapping Markovian Network Topologies.

    Science.gov (United States)

    Ge, Xiaohua; Han, Qing-Long

    2016-06-07

    This paper addresses the consensus problem for a continuous-time multiagent system (MAS) with Markovian network topologies and external disturbance. Different from some existing results, global jumping modes of the Markovian network topologies are not required to be completely available for consensus protocol design. A network topology mode regulator (NTMR) is first developed to decompose unavailable global modes into several overlapping groups, where overlapping groups refer to the scenario that there exist commonly shared local modes between any two distinct groups. The NTMR schedules which group modes each agent may access at every time step. Then a new group mode-dependent distributed consensus protocol on the basis of relative measurement outputs of neighboring agents is delicately constructed. In this sense, the proposed consensus protocol relies only on group and partial modes and eliminates the need for complete knowledge of global modes. Sufficient conditions on the existence of desired distributed consensus protocols are derived to ensure consensus of the MAS with a prescribed H∞ performance level. Two examples are provided to show the effectiveness of the proposed consensus protocol.

  7. The American Association for Thoracic Surgery Consensus Guidelines: Reasons and purpose.

    Science.gov (United States)

    Svensson, Lars G; Gillinov, A Marc; Weisel, Richard D; Keshavjee, Shaf; Bacha, Emile A; Moon, Marc R; Cameron, Duke E; Sugarbaker, David J; Adams, David H; Gaynor, J William; Coselli, Joseph S; Del Nido, Pedro J; Jones, David; Sundt, Thoralf M; Cohn, Lawrence H; Pomar, Jose L; Lytle, Bruce W; Schaff, Hartzell V

    2016-04-01

    The time interval for the doubling of medical knowledge continues to decline. Physicians, patients, administrators, government officials, and payors are struggling to keep up to date with the waves of new information and to integrate the knowledge into new patient treatment protocols, processes, and metrics. Guidelines, Consensus Guidelines, and Consensus Statements, moderated by seasoned content experts, offer one method to rapidly distribute new information in a timely manner and also guide minimal standards of treatment of clinical care pathways as they are developed as part of bundled care programs. These proposed Consensus Guidelines advance The American Association for Thoracic Surgery's mission of leading in cardiothoracic health care, education, innovation, and modeling excellence.

  8. Adaptive Leader-Following Consensus for Second-Order Time-Varying Nonlinear Multiagent Systems.

    Science.gov (United States)

    Hua, Changchun; You, Xiu; Guan, Xinping

    2017-06-01

    The leader-following consensus problem is investigated for second-order time-varying nonlinear multiagent systems with unmodeled dynamics and unknown parameters over directed communication topology. Under the assumption that the unknown nonlinearities satisfy Lipschitz conditions with time-varying gains, a local adaptive law is introduced for the design of consensus protocol that enable all followers' state variables to consensus with that of leader asymptotically. The proposed protocols are independent of system parameters and only require the relative state information of its neighbors, and hence they are fully distributed. Simulation examples are given to illustrate the effectiveness of the theoretical results.

  9. Observer-based consensus of networked thrust-propelled vehicles with directed graphs.

    Science.gov (United States)

    Cang, Weiye; Li, Zhongkui; Wang, Hanlei

    2017-04-15

    In this paper, we investigate the consensus problem for networked underactuated thrust-propelled vehicles (TPVs) interacting on directed graphs. We propose distributed observer-based consensus protocols, which avoid the reliance on the measurements of translational velocities and accelerations. Using the input-output analysis, we present necessary and sufficient conditions to ensure that the observer-based protocols can achieve consensus for both the cases without and with constant communication delays, provided that the communication graph contains a directed spanning tree. Simulation examples are finally provided to illustrate the effectiveness of the control schemes. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  10. Bruxism defined and graded: an international consensus

    NARCIS (Netherlands)

    Lobbezoo, F.; Ahlberg, J.; Glaros, A.G.; Kato, T.; Koyano, K.; Lavigne, G.J.; de Leeuw, R.; Manfredini, D.; Svensson, P.; Winocur, E.

    2013-01-01

    To date, there is no consensus about the definition and diagnostic grading of bruxism. A written consensus discussion was held among an international group of bruxism experts as to formulate a definition of bruxism and to suggest a grading system for its operationalisation. The expert group defined

  11. International veterinary epilepsy task force consensus proposal

    DEFF Research Database (Denmark)

    De Risio, Luisa; Bhatti, Sofie; Muñana, Karen

    2015-01-01

    This article outlines the consensus proposal on diagnosis of epilepsy in dogs by the International Veterinary Epilepsy Task Force. The aim of this consensus proposal is to improve consistency in the diagnosis of epilepsy in the clinical and research settings. The diagnostic approach to the patient...

  12. International Veterinary Epilepsy Task Force consensus proposal

    DEFF Research Database (Denmark)

    Bhatti, Sofie F M; De Risio, Luisa; Muñana, Karen;

    2015-01-01

    with the initial drug is unsatisfactory, and 4) when treatment changes should be considered. In this consensus proposal, an overview is given on the aim of AED treatment, when to start long-term treatment in canine epilepsy and which veterinary AEDs are currently in use for dogs. The consensus proposal for drug...

  13. Veto-Consensus Multiple Kernel Learning

    NARCIS (Netherlands)

    Y. Zhou; N. Hu; C.J. Spanos

    2016-01-01

    We propose Veto-Consensus Multiple Kernel Learning (VCMKL), a novel way of combining multiple kernels such that one class of samples is described by the logical intersection (consensus) of base kernelized decision rules, whereas the other classes by the union (veto) of their complements. The propose

  14. Gaussian moving averages and semimartingales

    DEFF Research Database (Denmark)

    Basse-O'Connor, Andreas

    2008-01-01

    In the present paper we study moving averages (also known as stochastic convolutions) driven by a Wiener process and with a deterministic kernel. Necessary and sufficient conditions on the kernel are provided for the moving average to be a semimartingale in its natural filtration. Our results...... are constructive - meaning that they provide a simple method to obtain kernels for which the moving average is a semimartingale or a Wiener process. Several examples are considered. In the last part of the paper we study general Gaussian processes with stationary increments. We provide necessary and sufficient...

  15. Leader-Following Consensus of Linear Multiagent Systems with State Observer under Switching Topologies

    Directory of Open Access Journals (Sweden)

    Lixin Gao

    2013-01-01

    Full Text Available The leader-following consensus problem of higher order multiagent systems is considered. The dynamics of each agent are given in general form of linear system, and the communication topology among the agents is assumed to be directed and switching. To track the leader, two kinds of distributed observer-based consensus protocols are proposed for each following agent, whose distributed observers are used to estimate the leader’s state and tracking error based on the relative outputs of the neighboring agents, respectively. Some sufficient consensus conditions are established by using parameter-dependent Lyapunov function method under a class of directed interaction topologies. As special cases, the consensus conditions for balanced and undirected interconnection topology cases can be obtained directly. The protocol design technique is based on algebraic graph theory, Riccati equation, and Sylvester equation. Finally, a simulation example is given to illustrate our obtained result.

  16. Proto col Design for Output Consensus of Port-controlled Hamiltonian Multi-agent Systems

    Institute of Scientific and Technical Information of China (English)

    LI Chang-Sheng; WANG Yu-Zhen

    2014-01-01

    This paper investigates the output consensus problem of port-controlled Hamiltonian (PCH) multi-agent systems with both fixed and switching topologies. Firstly, a distributed group output consensus protocol is designed via the energy shaping method to reach globally stability and group output consensus. Secondly, a new distributed control protocol is proposed by using the structural properties of the PCH systems. The advantage of this protocol is that it can transform the directed graph to the undirected graph by constructing a kind of virtual neighbors. Thirdly, a control protocol is designed with the extended LaSalle0s invariance principle developed for switched systems under the jointly connected topology condition to make all the agents reach output consensus when the topology is switching. Finally, some illustrative examples with simulations are provided to demonstrate the effectiveness of the protocols designed in this paper.

  17. Consensus statement on genetic research in dementia

    DEFF Research Database (Denmark)

    Rikkert, M.G. Olde; der, V van; Burns, A.

    2008-01-01

    In this article, the authors describe how the European Dementia Consensus Network developed a consensus on research ethics in dementia, taking into account the questions posed by the era of genetic research and its new research methods. The consensus process started with a Delphi procedure...... to analyze relevant stakeholders' positions by describing their statements on the possibilities and limitations of research into genetic determinants of Alzheimer disease and to describe and analyze the moral desirability of genetic research on Alzheimer disease. The conclusions drawn from the Delphi...... procedure fuelled the development of the consensus statement, which is presented in this paper. The consensus statement aims to stimulate ethically acceptable research in the field of dementia and the protection of vulnerable elderly patients with dementia from application of inadequate research methods...

  18. Model averaging and muddled multimodel inferences.

    Science.gov (United States)

    Cade, Brian S

    2015-09-01

    Three flawed practices associated with model averaging coefficients for predictor variables in regression models commonly occur when making multimodel inferences in analyses of ecological data. Model-averaged regression coefficients based on Akaike information criterion (AIC) weights have been recommended for addressing model uncertainty but they are not valid, interpretable estimates of partial effects for individual predictors when there is multicollinearity among the predictor variables. Multicollinearity implies that the scaling of units in the denominators of the regression coefficients may change across models such that neither the parameters nor their estimates have common scales, therefore averaging them makes no sense. The associated sums of AIC model weights recommended to assess relative importance of individual predictors are really a measure of relative importance of models, with little information about contributions by individual predictors compared to other measures of relative importance based on effects size or variance reduction. Sometimes the model-averaged regression coefficients for predictor variables are incorrectly used to make model-averaged predictions of the response variable when the models are not linear in the parameters. I demonstrate the issues with the first two practices using the college grade point average example extensively analyzed by Burnham and Anderson. I show how partial standard deviations of the predictor variables can be used to detect changing scales of their estimates with multicollinearity. Standardizing estimates based on partial standard deviations for their variables can be used to make the scaling of the estimates commensurate across models, a necessary but not sufficient condition for model averaging of the estimates to be sensible. A unimodal distribution of estimates and valid interpretation of individual parameters are additional requisite conditions. The standardized estimates or equivalently the t

  19. Model averaging and muddled multimodel inferences

    Science.gov (United States)

    Cade, Brian S.

    2015-01-01

    Three flawed practices associated with model averaging coefficients for predictor variables in regression models commonly occur when making multimodel inferences in analyses of ecological data. Model-averaged regression coefficients based on Akaike information criterion (AIC) weights have been recommended for addressing model uncertainty but they are not valid, interpretable estimates of partial effects for individual predictors when there is multicollinearity among the predictor variables. Multicollinearity implies that the scaling of units in the denominators of the regression coefficients may change across models such that neither the parameters nor their estimates have common scales, therefore averaging them makes no sense. The associated sums of AIC model weights recommended to assess relative importance of individual predictors are really a measure of relative importance of models, with little information about contributions by individual predictors compared to other measures of relative importance based on effects size or variance reduction. Sometimes the model-averaged regression coefficients for predictor variables are incorrectly used to make model-averaged predictions of the response variable when the models are not linear in the parameters. I demonstrate the issues with the first two practices using the college grade point average example extensively analyzed by Burnham and Anderson. I show how partial standard deviations of the predictor variables can be used to detect changing scales of their estimates with multicollinearity. Standardizing estimates based on partial standard deviations for their variables can be used to make the scaling of the estimates commensurate across models, a necessary but not sufficient condition for model averaging of the estimates to be sensible. A unimodal distribution of estimates and valid interpretation of individual parameters are additional requisite conditions. The standardized estimates or equivalently the

  20. Scalable Robust Principal Component Analysis Using Grassmann Averages

    DEFF Research Database (Denmark)

    Hauberg, Søren; Feragen, Aasa; Enficiaud, Raffi

    2016-01-01

    provide a simple algorithm for computing this Grassmann Average (GA), and show that the subspace estimate is less sensitive to outliers than PCA for general distributions. Because averages can be efficiently computed, we immediately gain scalability. We exploit robust averaging to formulate the Robust...

  1. Leader-Following Consensus Stability of Discrete-Time Linear Multiagent Systems with Observer-Based Protocols

    Directory of Open Access Journals (Sweden)

    Bingbing Xu

    2013-01-01

    Full Text Available We consider the leader-following consensus problem of discrete-time multiagent systems on a directed communication topology. Two types of distributed observer-based consensus protocols are considered to solve such a problem. The observers involved in the proposed protocols include full-order observer and reduced-order observer, which are used to reconstruct the state variables. Two algorithms are provided to construct the consensus protocols, which are based on the modified discrete-time algebraic Riccati equation and Sylvester equation. In light of graph and matrix theory, some consensus conditions are established. Finally, a numerical example is provided to illustrate the obtained result.

  2. Mean Square Consensus for Uncertain Multiagent Systems with Noises and Delays

    Directory of Open Access Journals (Sweden)

    Yuangong Sun

    2012-01-01

    Full Text Available This paper investigates the consensus problem in mean square for uncertain multiagent systems with stochastic measurement noises and symmetric or asymmetric time-varying delays. By combining the tools of stochastic analysis, algebraic graph theory, and matrix theory, we analyze the convergence of a class of distributed stochastic approximation type protocols with time-varying consensus gains. Numerical examples are also given to illustrate the theoretical results.

  3. [Spanish consensus on infantile haemangioma].

    Science.gov (United States)

    Baselga Torres, Eulalia; Bernabéu Wittel, José; van Esso Arbolave, Diego L; Febrer Bosch, María Isabel; Carrasco Sanz, Ángel; de Lucas Laguna, Raúl; Del Pozo Losada, Jesús; Hernández Martín, Ángela; Jiménez Montañés, Lorenzo; López Gutiérrez, Juan Carlos; Martín-Santiago, Ana; Redondo Bellón, Pedro; Ruíz-Canela Cáceres, Juan; Torrelo Fernández, Antonio; Vera Casaño, Ángel; Vicente Villa, María Asunción

    2016-11-01

    Infantile haemangiomas are benign tumours produced by the proliferation of endothelial cells of blood vessels, with a high incidence in children under the age of one year (4-10%). It is estimated that 12% of them require treatment. This treatment must be administered according to clinical practice guidelines, expert experience, patient characteristics and parent preferences. The consensus process was performed by using scientific evidence on the diagnosis and treatment of infantile haemangiomas, culled from a systematic review of the literature, together with specialist expert opinions. The recommendations issued were validated by the specialists, who also provided their level of agreement. This document contains recommendations on the classification, associations, complications, diagnosis, treatment, and follow-up of patients with infantile haemangioma. It also includes action algorithms, and addresses multidisciplinary management and referral criteria between the different specialities involved in the clinical management of this type of patient. The recommendations and the diagnostic and therapeutic algorithms of infantile haemangiomas contained in this document are a useful tool for the proper management of these patients. Copyright © 2015 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Consensus maps of cloned plant cuticle genes

    Institute of Scientific and Technical Information of China (English)

    Eviatar; Nevo

    2010-01-01

    Plant cuticle,which covers the plant surface,consists of waxes and cutins,and is associated with plant drought,cold,and salt resistance.Hitherto,at least 47 genes participating in the formation of plant cuticle have been cloned from Arabidopsis thaliana,Oryza sativa,Zea mays,Ricinus communis,Brassica napus,and Medicago truncatula;and about 85% of them encode proteins sharing above 50% identities with their rice homologous sequences.These cloned cuticle genes were mapped in silico on different chromosomes of rice and Arabidopsis,respectively.The mapping results revealed that plant cuticle genes were not evenly distributed in both genomes.About 40% of the mapped cuticle genes were located on chromosome 1 in Arabidopsis,while 20% of the mapped cuticle genes were located on chromosome 2 but none on chromosome 12 in rice.Some cloned plant cuticle genes have several rice homologous sequences,which might be produced by chromosomal segment duplication.The consensus map of cloned plant cuticle genes will provide important clues for the selection of candidate genes in a positional cloning of an unknown cuticle gene in plants.

  5. The role of fanatics in consensus formation

    Science.gov (United States)

    Gündüç, Semra

    2015-08-01

    A model of opinion dynamics with two types of agents as social actors are presented, using the Ising thermodynamic model as the dynamics template. The agents are considered as opportunists which live at sites and interact with the neighbors, or fanatics/missionaries which move from site to site randomly in persuasion of converting agents of opposite opinion with the help of opportunists. Here, the moving agents act as an external influence on the opportunists to convert them to the opposite opinion. It is shown by numerical simulations that such dynamics of opinion formation may explain some details of consensus formation even when one of the opinions are held by a minority. Regardless the distribution of the opinion, different size societies exhibit different opinion formation behavior and time scales. In order to understand general behavior, the scaling relations obtained by comparing opinion formation processes observed in societies with varying population and number of randomly moving agents are studied. For the proposed model two types of scaling relations are observed. In fixed size societies, increasing the number of randomly moving agents give a scaling relation for the time scale of the opinion formation process. The second type of scaling relation is due to the size dependent information propagation in finite but large systems, namely finite-size scaling.

  6. A Nonlinear Consensus Protocol of Multiagent Systems Considering Measuring Errors

    Directory of Open Access Journals (Sweden)

    Xiaochu Wang

    2013-01-01

    Full Text Available In order to avoid a potential waste of energy during consensus controls in the case where there exist measurement uncertainties, a nonlinear protocol is proposed for multiagent systems under a fixed connected undirected communication topology and extended to both the cases with full and partial access a reference. Distributed estimators are utilized to help all agents agree on the understandings of the reference, even though there may be some agents which cannot access to the reference directly. An additional condition is also considered, where self-known configuration offsets are desired. Theoretical analyses of stability are given. Finally, simulations are performed, and results show that the proposed protocols can lead agents to achieve loose consensus and work effectively with less energy cost to keep the formation, which have illustrated the theoretical results.

  7. Reaching Nonlinear Consensus via Non-Autonomous Polynomial Stochastic Operators

    Science.gov (United States)

    Saburov, Mansoor; Saburov, Khikmat

    2017-03-01

    This paper is a continuation of our previous studies on nonlinear consensus which unifies and generalizes all previous results. We consider a nonlinear protocol for a structured time-varying synchronous multi-agent system. We present an opinion sharing dynamics of the multi-agent system as a trajectory of non-autonomous polynomial stochastic operators associated with multidimensional stochastic hyper-matrices. We show that the multi-agent system eventually reaches to a nonlinear consensus if either one of the following two conditions is satisfied: (i) every member of the group people has a positive subjective distribution on the given task after some revision steps or (ii) all entries of some multidimensional stochastic hyper-matrix are positive.

  8. Vocal attractiveness increases by averaging.

    Science.gov (United States)

    Bruckert, Laetitia; Bestelmeyer, Patricia; Latinus, Marianne; Rouger, Julien; Charest, Ian; Rousselet, Guillaume A; Kawahara, Hideki; Belin, Pascal

    2010-01-26

    Vocal attractiveness has a profound influence on listeners-a bias known as the "what sounds beautiful is good" vocal attractiveness stereotype [1]-with tangible impact on a voice owner's success at mating, job applications, and/or elections. The prevailing view holds that attractive voices are those that signal desirable attributes in a potential mate [2-4]-e.g., lower pitch in male voices. However, this account does not explain our preferences in more general social contexts in which voices of both genders are evaluated. Here we show that averaging voices via auditory morphing [5] results in more attractive voices, irrespective of the speaker's or listener's gender. Moreover, we show that this phenomenon is largely explained by two independent by-products of averaging: a smoother voice texture (reduced aperiodicities) and a greater similarity in pitch and timbre with the average of all voices (reduced "distance to mean"). These results provide the first evidence for a phenomenon of vocal attractiveness increases by averaging, analogous to a well-established effect of facial averaging [6, 7]. They highlight prototype-based coding [8] as a central feature of voice perception, emphasizing the similarity in the mechanisms of face and voice perception.

  9. Randomized Optimal Consensus of Multi-agent Systems

    CERN Document Server

    Shi, Guodong

    2011-01-01

    In this paper, we formulate and solve a randomized optimal consensus problem for multi-agent systems with stochastically time-varying interconnection topology. The considered multi-agent system with a simple randomized iterating rule achieves an almost sure consensus meanwhile solving the optimization problem $\\min_{z\\in \\mathds{R}^d}\\ \\sum_{i=1}^n f_i(z),$ in which the optimal solution set of objective function $f_i$ corresponding to agent $i$ can only be observed by agent $i$ itself. At each time step, each agent independently and randomly chooses either taking an average among its neighbor set, or projecting onto the optimal solution set of its own optimization component. Both directed and bidirectional communication graphs are studied. Connectivity conditions are proposed to guarantee an optimal consensus almost surely with proper convexity and intersection assumptions. The convergence analysis is carried out using convex analysis. The results illustrate that a group of autonomous agents can reach an opti...

  10. Location-aided Distributed Primary User Identification in a Cognitive Radio Scenario

    CERN Document Server

    Belanovic, Pavle; Zazo, Santiago

    2011-01-01

    We address a cognitive radio scenario, where a number of secondary users performs identification of which primary user, if any, is transmitting, in a distributed way and using limited location information. We propose two fully distributed algorithms: the first is a direct identification scheme, and in the other a distributed sub-optimal detection based on a simplified Neyman-Pearson energy detector precedes the identification scheme. Both algorithms are studied analytically in a realistic transmission scenario, and the advantage obtained by detection pre-processing is also verified via simulation. Finally, we give details of their fully distributed implementation via consensus averaging algorithms.

  11. International Veterinary Epilepsy Task Force consensus proposal

    DEFF Research Database (Denmark)

    Bhatti, Sofie F M; De Risio, Luisa; Muñana, Karen

    2015-01-01

    with the initial drug is unsatisfactory, and 4) when treatment changes should be considered. In this consensus proposal, an overview is given on the aim of AED treatment, when to start long-term treatment in canine epilepsy and which veterinary AEDs are currently in use for dogs. The consensus proposal for drug...... treatment protocols, 1) is based on current published evidence-based literature, 2) considers the current legal framework of the cascade regulation for the prescription of veterinary drugs in Europe, and 3) reflects the authors' experience. With this paper it is aimed to provide a consensus...

  12. Averaged Electroencephalic Audiometry in Infants

    Science.gov (United States)

    Lentz, William E.; McCandless, Geary A.

    1971-01-01

    Normal, preterm, and high-risk infants were tested at 1, 3, 6, and 12 months of age using averaged electroencephalic audiometry (AEA) to determine the usefulness of AEA as a measurement technique for assessing auditory acuity in infants, and to delineate some of the procedural and technical problems often encountered. (KW)

  13. Ergodic averages via dominating processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Mengersen, Kerrie

    2006-01-01

    We show how the mean of a monotone function (defined on a state space equipped with a partial ordering) can be estimated, using ergodic averages calculated from upper and lower dominating processes of a stationary irreducible Markov chain. In particular, we do not need to simulate the stationary ...

  14. Averaging VMAT treatment plans for multi-criteria navigation

    CERN Document Server

    Craft, David; Unkelbach, Jan

    2013-01-01

    The main approach to smooth Pareto surface navigation for radiation therapy multi-criteria treatment planning involves taking real-time averages of pre-computed treatment plans. In fluence-based treatment planning, fluence maps themselves can be averaged, which leads to the dose distributions being averaged due to the linear relationship between fluence and dose. This works for fluence-based photon plans and proton spot scanning plans. In this technical note, we show that two or more sliding window volumetric modulated arc therapy (VMAT) plans can be combined by averaging leaf positions in a certain way, and we demonstrate that the resulting dose distribution for the averaged plan is approximately the average of the dose distributions of the original plans. This leads to the ability to do Pareto surface navigation, i.e. interactive multi-criteria exploration of VMAT plan dosimetric tradeoffs.

  15. Managing Carious Lesions: Consensus Recommendations on Carious Tissue Removal

    National Research Council Canada - National Science Library

    Schwendicke, F; Frencken, J.E; Bjørndal, L; Maltz, M; Manton, D.J; Ricketts, D; Van Landuyt, K; Banerjee, A; Campus, G; Doméjean, S; Fontana, M; Leal, S; Lo, E; Machiulskiene, V; Schulte, A; Splieth, C; Zandona, A.F; Innes, N.P.T

    2016-01-01

    The International Caries Consensus Collaboration undertook a consensus process and here presents clinical recommendations for carious tissue removal and managing cavitated carious lesions, including...

  16. OGC Consensus: How Successful Standards Are Made

    Directory of Open Access Journals (Sweden)

    Carl Reed

    2015-09-01

    Full Text Available This paper describes the history, background, and current status of the Open Geospatial Consortium (OGC standards development consensus process. The roots of the formation of the OGC lie in the early 1990s when a very strong market requirement for exchanging GIS data content was clearly stated. At that time, each GIS vendor had their own formats for publishing and/or exchanging their GIS data. There was no mechanism or organization that provided a forum for the GIS vendors and GIS data users to collaborate and agree on how to share GIS data. That requirement, along with the vision of a few individuals, led to the formation of the OGC. This paper describes the early development of the consensus process in the OGC, how this process has evolved over time, why consensus is so important for defining open standards that are implemented in the marketplace, and the future of the OGC consensus process.

  17. Possibility Distribution-Based Approach for MAGDM With Hesitant Fuzzy Linguistic Information.

    Science.gov (United States)

    Wu, Zhibin; Xu, Jiuping

    2016-03-01

    In group decision making (GDM) with qualitative settings, experts may require several possible linguistic values rather than a single term to express their preferences. A hesitant fuzzy linguistic term set has recently been developed to manage this situation. In line with this development, in this paper, we present a new framework model to address multiple attribute GDM with hesitant fuzzy linguistic information. First, the concept of a possibility distribution is defined. Based on the possibility distributions, some aggregation operators such as the hesitant fuzzy linguistic weighted average operator and the hesitant fuzzy linguistic ordered weighted average operator are proposed. A consensus measure is then defined and a consensus reaching process is given which uses different identification and direction rules compared with the existing methods. A selection process is also described to rank the alternatives. Both processes are necessary to support stakeholders when making rational decisions. Finally, two simulated examples are given to verify the practicability of the proposed approach.

  18. Population conference: consensus and conflict.

    Science.gov (United States)

    Willson, P D

    1984-01-01

    The United Nations-sponsored International Conference on Population held in Mexico City was both a rejection and an affirmation of a new policy of the Reagan administration. The policy denies international family planning funds to nongovernmental organizations that perform or actively promote abortion as a family planning method in other nations. A compromise statement was accepted urging governments to take appropriate measures to discourage abortion as a family planning method and when possible to provide for the humane treatment and counseling of women ho resorted to abortion. The statement on abortion was 1 of 88 reccomendations approved by the conference. The commitment expressed in the 10-year-old World Population Plan of Action to the rights and responsiblity to all people as reaffirmed. The conference also endorsed family life education and sex education as well as suitable family planning, information and services for adolescents, with due consideration given to the role, rights and obligations of parents. Increased support for international population and family planning programs was urged and World Bank President, Clausen, urged a 4-fold increase in international funding by the year 2000. Most of the conference's recommendations re devoted to the broad range of population policy issues, including morbidity and mortality, international and internal migration, the relationship between population and economic development and the status of women. The purpose of the recommendations is to increase the momentum of international support. The Mexico City conference was characterized by a remarkable degree of consensus about population policies with respect to integration with economic development, the need to respect individual rights and the recognition that all nations have sovereign rights to develop and implement their own population policies. Conflict and controversy arose in the areas of the arms race and the Middle East. The US position on abortion funding

  19. Multiagent Based Distributed Control for State-of-Charge Balance of Distributed Energy Storage in DC microgrids

    DEFF Research Database (Denmark)

    Li, Chendan; Dragicevic, Tomislav; Garcia Plaza, Manuel

    2014-01-01

    information for scheduling voltage autonomously. State-space analysis on a single energy storage unit and simulation verification shows that the proposed method has two advantages. Firstly, modifying the reference voltage given has less impact on system stability compared to gain scheduling. Secondly......In this paper, a distributed multiagent based algorithm is proposed to achieve SoC balance for DES in the DC microgrid by means of voltage scheduling. Reference voltage given is adjusted instead of droop gain. Dynamic average consensus algorithm is explored in each agent to get the required......, by adopting multiagent methodology, the proposed distributed control has less communication dependence and more reliable during communication topology changes....

  20. Event-Based Consensus for Linear Multiagent Systems Without Continuous Communication.

    Science.gov (United States)

    Xing, Lantao; Wen, Changyun; Guo, Fanghong; Liu, Zhitao; Su, Hongye

    2016-10-04

    In this paper, we propose a new distributed event-trigger consensus protocol for linear multiagent systems with external disturbances. Two consensus problems are considered: one is a leader-follower case and the other is a nonleader case. Different from the existing results, our proposed scheme enables each agent to decide when to transmit its state signals to its neighbors such that continuous communication between neighboring agents is avoided. Clearly, this can largely decrease the communication burden of the whole communication network. Besides, since the control signal for each agent is discontinuous because of the event-triggering mechanism, the existence of a solution for the closed-loop system in the classical sense may not be guaranteed. To solve this problem, we employ a nonsmooth analysis technique including differential inclusion and Filippov solution. Through nonsmooth Lyapunov analysis, it is shown that uniformly bounded consensus results are derived and the bound of the consensus error is adjustable by choosing suitable design parameters.

  1. Scaled Group Consensus in Multiagent Systems With First/Second-Order Continuous Dynamics.

    Science.gov (United States)

    Yu, Junyan; Shi, Yang

    2017-08-29

    We investigate scaled group consensus problems of multiagent systems with first/second-order linear continuous dynamics. For a complex network consisting of two subnetworks with different physical quantities or task distributions, it is concerned with this case that the agents' states in one subnetwork converge to a consistent value asymptotically, while the states in the other subnetwork approach another value with a ratio of the former. For the case of the information exchange being directed, novel consensus protocols are designed for both first-order and second-order dynamics to solve the scaled group consensus problems. By utilizing algebra theory, graph theory, and Lyapunov stability theory, several necessary and sufficient conditions are established to guarantee the agents' states reaching the scaled group consensus asymptotically. Finally, several simulation results are presented to demonstrate the effectiveness of the theoretical results.

  2. Analyses of integrated aircraft cabin contaminant monitoring network based on Kalman consensus filter.

    Science.gov (United States)

    Wang, Rui; Li, Yanxiao; Sun, Hui; Chen, Zengqiang

    2017-07-11

    The modern civil aircrafts use air ventilation pressurized cabins subject to the limited space. In order to monitor multiple contaminants and overcome the hypersensitivity of the single sensor, the paper constructs an output correction integrated sensor configuration using sensors with different measurement theories after comparing to other two different configurations. This proposed configuration works as a node in the contaminant distributed wireless sensor monitoring network. The corresponding measurement error models of integrated sensors are also proposed by using the Kalman consensus filter to estimate states and conduct data fusion in order to regulate the single sensor measurement results. The paper develops the sufficient proof of the Kalman consensus filter stability when considering the system and the observation noises and compares the mean estimation and the mean consensus errors between Kalman consensus filter and local Kalman filter. The numerical example analyses show the effectiveness of the algorithm. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  3. High average power supercontinuum sources

    Indian Academy of Sciences (India)

    J C Travers

    2010-11-01

    The physical mechanisms and basic experimental techniques for the creation of high average spectral power supercontinuum sources is briefly reviewed. We focus on the use of high-power ytterbium-doped fibre lasers as pump sources, and the use of highly nonlinear photonic crystal fibres as the nonlinear medium. The most common experimental arrangements are described, including both continuous wave fibre laser systems with over 100 W pump power, and picosecond mode-locked, master oscillator power fibre amplifier systems, with over 10 kW peak pump power. These systems can produce broadband supercontinua with over 50 and 1 mW/nm average spectral power, respectively. Techniques for numerical modelling of the supercontinuum sources are presented and used to illustrate some supercontinuum dynamics. Some recent experimental results are presented.

  4. Pragmatism and Political Pluralism - Consensus and Pluralism

    Directory of Open Access Journals (Sweden)

    Michele Marsonet

    2015-07-01

    In our day the German philosopher Jürgen Habermas has in a way revived these Peircean insights, putting forward an influential theory to the effect that consensus indeed plays a key role in human praxis, so that the primary task of philosophy is to foster it by eliminating the disagreement which we constantly have to face in the course of our daily life. In his “communicative theory of consensus,” furthermore, he claims that human communication rests on an implicit commitment to a sort of “ideal speech situation” which is the normative foundation of agreement in linguistic matters. Consequently, the quest for consensus is a constitutive feature of our nature of (rational human beings: rationality and consensus are tied together. A very strong consequence derives from Habermas’ premises: were we to abandon the search for consensus we would lose rationality, too, and this makes us understand that he views the pursuit of consensus as a regulative principle (rather than as a merely practical objective. Rescher opposes both Peirce’s eschatological view and Habermas’ regulative and idealized one.

  5. Measuring Complexity through Average Symmetry

    OpenAIRE

    Alamino, Roberto C.

    2015-01-01

    This work introduces a complexity measure which addresses some conflicting issues between existing ones by using a new principle - measuring the average amount of symmetry broken by an object. It attributes low (although different) complexity to either deterministic or random homogeneous densities and higher complexity to the intermediate cases. This new measure is easily computable, breaks the coarse graining paradigm and can be straightforwardly generalised, including to continuous cases an...

  6. ANALYSIS OF THE FACTORS AFFECTING THE AVERAGE

    Directory of Open Access Journals (Sweden)

    Carmen BOGHEAN

    2013-12-01

    Full Text Available Productivity in agriculture most relevantly and concisely expresses the economic efficiency of using the factors of production. Labour productivity is affected by a considerable number of variables (including the relationship system and interdependence between factors, which differ in each economic sector and influence it, giving rise to a series of technical, economic and organizational idiosyncrasies. The purpose of this paper is to analyse the underlying factors of the average work productivity in agriculture, forestry and fishing. The analysis will take into account the data concerning the economically active population and the gross added value in agriculture, forestry and fishing in Romania during 2008-2011. The distribution of the average work productivity per factors affecting it is conducted by means of the u-substitution method.

  7. An Interactive Multi-Model for Consensus on Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Kocarev, Ljupco [University of California, San Diego

    2014-07-02

    This project purports to develop a new scheme for forming consensus among alternative climate models, that give widely divergent projections as to the details of climate change, that is more intelligent than simply averaging the model outputs, or averaging with ex post facto weighting factors. The method under development effectively allows models to assimilate data from one another in run time with weights that are chosen in an adaptive training phase using 20th century data, so that the models synchronize with one another as well as with reality. An alternate approach that is being explored in parallel is the automated combination of equations from different models in an expert-system-like framework.

  8. Implant dentistry education in Europe: 5 years after the Association for Dental Education in Europe consensus report.

    Science.gov (United States)

    Koole, S; Vandeweghe, S; Mattheos, N; De Bruyn, H

    2014-03-01

    To promote consensus on implant dentistry university education in Europe, a workshop amongst university teachers and opinion leaders was organised in 2008. As a result, guidelines on both under- and postgraduate education were issued. This study aims to investigate the current status of university teaching of implant dentistry and the impact of the recommendations for teaching and assessment, 5 years after the first consensus. Finally, this report attempts to identify future directions in education within the discipline. An online survey was distributed amongst 105 academic leaders in implant education in Europe, and 52 questionnaires were returned (response rate 50%). The average amount of implant dentistry in undergraduate curricula has increased to 74 h, compared to 36 h in 2008, and the inclusion of pre-clinical and clinical education has increased. No change occurred with regard to the aimed competence levels. It was suggested that certain implant procedures including surgery should be provided by dentists after attending additional courses, whilst complex treatments will still require specialist training. The 2008 workshop guidelines have been implemented to a varying extent (25-100%) in under- and postgraduate education. Main reported implementation barriers included limited time availability in the curriculum and limited financial/material resources. Future discussions about implant dentistry in Europe should be focused towards integration in current dental curricula, approaches to overcome barriers and the relations with and role of industrial partners. Implant dentistry is increasingly integrating in undergraduate dental education. Development of the consensus guidelines in 2008 may have facilitated this process. Nevertheless, further progress is needed on all educational levels to align training of professionals to the growing treatment needs of the population. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Fluctuations of wavefunctions about their classical average

    Energy Technology Data Exchange (ETDEWEB)

    Benet, L [Centro Internacional de Ciencias, Ciudad Universitaria, Chamilpa, Cuernavaca (Mexico); Flores, J [Centro Internacional de Ciencias, Ciudad Universitaria, Chamilpa, Cuernavaca (Mexico); Hernandez-Saldana, H [Centro Internacional de Ciencias, Ciudad Universitaria, Chamilpa, Cuernavaca (Mexico); Izrailev, F M [Centro Internacional de Ciencias, Ciudad Universitaria, Chamilpa, Cuernavaca (Mexico); Leyvraz, F [Centro Internacional de Ciencias, Ciudad Universitaria, Chamilpa, Cuernavaca (Mexico); Seligman, T H [Centro Internacional de Ciencias, Ciudad Universitaria, Chamilpa, Cuernavaca (Mexico)

    2003-02-07

    Quantum-classical correspondence for the average shape of eigenfunctions and the local spectral density of states are well-known facts. In this paper, the fluctuations of the quantum wavefunctions around the classical value are discussed. A simple random matrix model leads to a Gaussian distribution of the amplitudes whose width is determined by the classical shape of the eigenfunction. To compare this prediction with numerical calculations in chaotic models of coupled quartic oscillators, we develop a rescaling method for the components. The expectations are broadly confirmed, but deviations due to scars are observed. This effect is much reduced when both Hamiltonians have chaotic dynamics.

  10. Fluctuations of wavefunctions about their classical average

    CERN Document Server

    Bénet, L; Hernandez-Saldana, H; Izrailev, F M; Leyvraz, F; Seligman, T H

    2003-01-01

    Quantum-classical correspondence for the average shape of eigenfunctions and the local spectral density of states are well-known facts. In this paper, the fluctuations of the quantum wavefunctions around the classical value are discussed. A simple random matrix model leads to a Gaussian distribution of the amplitudes whose width is determined by the classical shape of the eigenfunction. To compare this prediction with numerical calculations in chaotic models of coupled quartic oscillators, we develop a rescaling method for the components. The expectations are broadly confirmed, but deviations due to scars are observed. This effect is much reduced when both Hamiltonians have chaotic dynamics.

  11. Reaching a consensus: a discrete nonlinear time-varying case

    Science.gov (United States)

    Saburov, M.; Saburov, K.

    2016-07-01

    In this paper, we have considered a nonlinear protocol for a structured time-varying and synchronous multi-agent system. By means of cubic triple stochastic matrices, we present an opinion sharing dynamics of the multi-agent system as a trajectory of a non-homogeneous system of cubic triple stochastic matrices. We show that the multi-agent system eventually reaches to a consensus if either of the following two conditions is satisfied: (1) every member of the group people has a positive subjective distribution on the given task after some revision steps or (2) all entries of some cubic triple stochastic matrix are positive.

  12. Bipartite opinion forming: Towards consensus over coopetition networks

    Science.gov (United States)

    Hou, Bo; Chen, Yao; Liu, Guangbin; Sun, Fuchun; Li, Hongbo

    2015-12-01

    Within the framework of signed graph and multi-agent systems, this paper investigates the distributed bipartite opinion forming problem over coopetition networks. Several sufficient algebraic and geometric topology conditions that guarantee consensus, regardless of the magnitudes of individual coupling strengths among the agents, have been derived by exploring the interaction direction patterns. All the criteria presented do not require the global knowledge of the coupling weights of the entire network, and thus are easier to check. The effectiveness of the theoretical results are illustrated by numerical examples.

  13. European consensus statement on leptospirosis in dogs and cats.

    Science.gov (United States)

    Schuller, S; Francey, T; Hartmann, K; Hugonnard, M; Kohn, B; Nally, J E; Sykes, J

    2015-03-01

    Leptospirosis is a zoonotic disease with a worldwide distribution affecting most mammalian species. Clinical leptospirosis is common in dogs but appears to be rare in cats. Both dogs and cats, however, can shed leptospires in the urine. This is problematic as it can lead to exposure of humans. The control of leptospirosis, therefore, is important not only from an animal but also from a public health perspective. The aim of this consensus statement is to raise awareness of leptospirosis and to outline the current knowledge on the epidemiology, clinical features, diagnostic tools, prevention and treatment measures relevant to canine and feline leptospirosis in Europe.

  14. Geographic Gossip: Efficient Averaging for Sensor Networks

    CERN Document Server

    Dimakis, Alexandros G; Wainwright, Martin J

    2007-01-01

    Gossip algorithms for distributed computation are attractive due to their simplicity, distributed nature, and robustness in noisy and uncertain environments. However, using standard gossip algorithms can lead to a significant waste in energy by repeatedly recirculating redundant information. For realistic sensor network model topologies like grids and random geometric graphs, the inefficiency of gossip schemes is related to the slow mixing times of random walks on the communication graph. We propose and analyze an alternative gossiping scheme that exploits geographic information. By utilizing geographic routing combined with a simple resampling method, we demonstrate substantial gains over previously proposed gossip protocols. For regular graphs such as the ring or grid, our algorithm improves standard gossip by factors of $n$ and $\\sqrt{n}$ respectively. For the more challenging case of random geometric graphs, our algorithm computes the true average to accuracy $\\epsilon$ using $O(\\frac{n^{1.5}}{\\sqrt{\\log ...

  15. Democracy-based consensus in medicine.

    Science.gov (United States)

    Greco, Massimiliano; Zangrillo, Alberto; Mucchetti, Marta; Nobile, Leda; Landoni, Paolo; Bellomo, Rinaldo; Landoni, Giovanni

    2015-04-01

    High-quality evidence and derived guidelines, as typically published in major academic journals, are a major process that shapes physician decision-making worldwide. However, for many aspects of medical practice, there is a lack of High-quality evidence or an overload of somewhat contradictory low-quality information, which makes decision-making a difficult, uncertain, and unpredictable process. When the issues in question are important and evidence limited or controversial, the medical community seeks to establish common ground for "best practice" through consensus conferences and consensus statements or guidelines. Such consensus statements are seen as a useful tool to establish expert agreement, define the boundaries of acceptable practice, provide priorities for the research agenda, and obtain opinions from different countries and healthcare systems. This standard approach, however, can be criticized for being elitist, noninclusive, and poorly representative of the community of clinicians who will have to make decisions about the implementation of such recommendations. Accordingly, the authors propose a new model based on a combination of a local core meeting (detailed review and expert input) followed by a worldwide web-based network assessment (democracy-based consensus). The authors already have applied this approach to develop consensus on all nonsurgical interventions that increase or reduce perioperative mortality in critically ill patients and in those with acute kidney injury. The methodology was based on 5 sequential local and web-based steps. Both a panel of experts and a large number of professionals from all over the world were involved, giving birth to a new type of "democracy-based consensus." This new type of "democracy-based consensus" has the potential to increase grass-root clinician involvement, expand the reach to less-developed countries, provide a more global perspective on proposed interventions, and perhaps more importantly, increase

  16. Observer-based consensus in networks of discrete-time switched linear dynamics under a fixed topology

    Science.gov (United States)

    Xin, Youming; Li, Yuxia

    2016-09-01

    This paper considers the consensus problem of discrete-time switched linear multi-agent systems under a fixed communication topology. An observer-based protocol with sampled data is proposed for solving such a problem. Assume that the digraph has a directed spanning tree and that all switched subsystem of each agent are stabilisable and detectable. It is shown that the proposed protocol solves the consensus problem when the sampling period is sufficiently small and the average dwell time of the switching signal is sufficiently large. Moreover, to reduce the conservatism, a sufficient condition for consensus is obtained to design the feedback gain matrices and the observer gain matrices by linear matrix inequalities, which guarantee that consensus can be achieved when the sampling period and the average dwell time are in the general case. Finally, the effectiveness of the theoretical results is demonstrated through an example.

  17. Distributed Sensor Fusion for Scalar Field Mapping Using Mobile Sensor Networks.

    Science.gov (United States)

    La, Hung Manh; Sheng, Weihua

    2013-04-01

    In this paper, autonomous mobile sensor networks are deployed to measure a scalar field and build its map. We develop a novel method for multiple mobile sensor nodes to build this map using noisy sensor measurements. Our method consists of two parts. First, we develop a distributed sensor fusion algorithm by integrating two different distributed consensus filters to achieve cooperative sensing among sensor nodes. This fusion algorithm has two phases. In the first phase, the weighted average consensus filter is developed, which allows each sensor node to find an estimate of the value of the scalar field at each time step. In the second phase, the average consensus filter is used to allow each sensor node to find a confidence of the estimate at each time step. The final estimate of the value of the scalar field is iteratively updated during the movement of the mobile sensors via weighted average. Second, we develop the distributed flocking-control algorithm to drive the mobile sensors to form a network and track the virtual leader moving along the field when only a small subset of the mobile sensors know the information of the leader. Experimental results are provided to demonstrate our proposed algorithms.

  18. on the performance of Autoregressive Moving Average Polynomial ...

    African Journals Online (AJOL)

    Timothy Ademakinwa

    Moving Average Polynomial Distributed Lag (ARMAPDL) model. The parameters of these models were estimated using least squares and Newton Raphson iterative methods. ..... Global Journal of Mathematics and Statistics. Vol. 1. No.

  19. Peakedness of Weighted Averages of Jointly Distributed Random Variables.

    Science.gov (United States)

    1985-10-01

    under the integral sign is permissible here, so that ah’(a) f L Ix =U (---gl(u)(t- u) du -2~ t-a t - au =f f(u, --- (t -u) du. t f tu i- "u’ t -u) du...differentiation under the integral sign , we note that f Ifu, t - ) Idu əlf -u ( )daa which follows from (2.1). -4- This condition is clearly not a

  20. Spatial averaging infiltration model for layered soil

    Institute of Scientific and Technical Information of China (English)

    HU HePing; YANG ZhiYong; TIAN FuQiang

    2009-01-01

    To quantify the influences of soil heterogeneity on infiltration, a spatial averaging infiltration model for layered soil (SAI model) is developed by coupling the spatial averaging approach proposed by Chen et al. and the Generalized Green-Ampt model proposed by Jia et al. In the SAI model, the spatial heterogeneity along the horizontal direction is described by a probability distribution function, while that along the vertical direction is represented by the layered soils. The SAI model is tested on a typical soil using Monte Carlo simulations as the base model. The results show that the SAI model can directly incorporate the influence of spatial heterogeneity on infiltration on the macro scale. It is also found that the homogeneous assumption of soil hydraulic conductivity along the horizontal direction will overestimate the infiltration rate, while that along the vertical direction will underestimate the infiltration rate significantly during rainstorm periods. The SAI model is adopted in the spatial averaging hydrological model developed by the authors, and the results prove that it can be applied in the macro-scale hydrological and land surface process modeling in a promising way.

  1. Spatial averaging infiltration model for layered soil

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To quantify the influences of soil heterogeneity on infiltration, a spatial averaging infiltration model for layered soil (SAI model) is developed by coupling the spatial averaging approach proposed by Chen et al. and the Generalized Green-Ampt model proposed by Jia et al. In the SAI model, the spatial hetero- geneity along the horizontal direction is described by a probability distribution function, while that along the vertical direction is represented by the layered soils. The SAI model is tested on a typical soil using Monte Carlo simulations as the base model. The results show that the SAI model can directly incorporate the influence of spatial heterogeneity on infiltration on the macro scale. It is also found that the homogeneous assumption of soil hydraulic conductivity along the horizontal direction will overes- timate the infiltration rate, while that along the vertical direction will underestimate the infiltration rate significantly during rainstorm periods. The SAI model is adopted in the spatial averaging hydrological model developed by the authors, and the results prove that it can be applied in the macro-scale hy- drological and land surface process modeling in a promising way.

  2. Two-phase analysis in consensus genetic mapping.

    Science.gov (United States)

    Ronin, Y; Mester, D; Minkov, D; Belotserkovski, R; Jackson, B N; Schnable, P S; Aluru, S; Korol, A

    2012-05-01

    Numerous mapping projects conducted on different species have generated an abundance of mapping data. Consequently, many multilocus maps have been constructed using diverse mapping populations and marker sets for the same organism. The quality of maps varies broadly among populations, marker sets, and software used, necessitating efforts to integrate the mapping information and generate consensus maps. The problem of consensus genetic mapping (MCGM) is by far more challenging compared with genetic mapping based on a single dataset, which by itself is also cumbersome. The additional complications introduced by consensus analysis include inter-population differences in recombination rate and exchange distribution along chromosomes; variations in dominance of the employed markers; and use of different subsets of markers in different labs. Hence, it is necessary to handle arbitrary patterns of shared sets of markers and different level of mapping data quality. In this article, we introduce a two-phase approach for solving MCGM. In phase 1, for each dataset, multilocus ordering is performed combined with iterative jackknife resampling to evaluate the stability of marker orders. In this phase, the ordering problem is reduced to the well-known traveling salesperson problem (TSP). Namely, for each dataset, we look for order that gives minimum sum of recombination distances between adjacent markers. In phase 2, the optimal consensus order of shared markers is selected from the set of allowed orders and gives the minimal sum of total lengths of nonconflicting maps of the chromosome. This criterion may be used in different modifications to take into account the variation in quality of the original data (population size, marker quality, etc.). In the foregoing formulation, consensus mapping is considered as a specific version of TSP that can be referred to as "synchronized TSP." The conflicts detected after phase 1 are resolved using either a heuristic algorithm over the

  3. [SECOT consensus on medial femorotibial osteoarthritis].

    Science.gov (United States)

    Moreno, A; Silvestre, A; Carpintero, P

    2013-01-01

    A consensus, prepared by SECOT, is presented on the management of medial knee compartment osteoarthritis, in order to establish clinical criteria and recommendations directed at unifying the criteria in its management, dealing with the factors involved in the pathogenesis of medial femorotibial knee osteoarthritis, the usefulness of diagnostic imaging techniques, and the usefulness of arthroscopy. Conservative and surgical treatments are also analysed. The experts consulted showed a consensus (agreed or disagreed) in 65.8% of the items considered, leaving 14items where no consensus was found, which included the aetiopathogenesis of the osteoarthritis, the value of NMR in degenerative disease, the usefulness of COX-2 and the chondroprotective drugs, as well as on the ideal valgus tibial osteotomy technique. © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  4. Reaching Consensus by Allowing Moments of Indecision

    Science.gov (United States)

    Svenkeson, A.; Swami, A.

    2015-10-01

    Group decision-making processes often turn into a drawn out and costly battle between two opposing subgroups. Using analytical arguments based on a master equation description of the opinion dynamics occurring in a three-state model of cooperatively interacting units, we show how the capability of a social group to reach consensus can be enhanced when there is an intermediate state for indecisive individuals to pass through. The time spent in the intermediate state must be relatively short compared to that of the two polar states in order to create the beneficial effect. Furthermore, the cooperation between individuals must not be too low, as the benefit to consensus is possible only when the cooperation level exceeds a specific threshold. We also discuss how zealots, agents that remain in one state forever, can affect the consensus among the rest of the population by counteracting the benefit of the intermediate state or making it virtually impossible for an opposition to form.

  5. Consensus for Linear Multiagent Systems With Time-Varying Delays: A Frequency Domain Perspective.

    Science.gov (United States)

    Chen, Yuanye; Shi, Yang

    2016-07-27

    This paper investigates the consensus problem for multiagent systems with time-varying delays. The bounded delays can be arbitrarily fast time-varying. The communication topology is assumed to be undirected and fixed. With general linear dynamics under average state feedback protocols, the consensus problem is then transformed into the robust control problem. Further, sufficient frequency domain criteria are established in terms of small gain theorem by analyzing the delay dependent gains for both continuous-time and discrete-time systems. The controller synthesis problems can be solved by applying the frequency domain design methods. Numerical examples are demonstrated to verify the effectiveness of the proposed approaches.

  6. Data-Driven Multiagent Systems Consensus Tracking Using Model Free Adaptive Control.

    Science.gov (United States)

    Bu, Xuhui; Hou, Zhongsheng; Zhang, Hongwei

    2017-03-14

    This paper investigates the data-driven consensus tracking problem for multiagent systems with both fixed communication topology and switching topology by utilizing a distributed model free adaptive control (MFAC) method. Here, agent's dynamics are described by unknown nonlinear systems and only a subset of followers can access the desired trajectory. The dynamical linearization technique is applied to each agent based on the pseudo partial derivative, and then, a distributed MFAC algorithm is proposed to ensure that all agents can track the desired trajectory. It is shown that the consensus error can be reduced for both time invariable and time varying desired trajectories. The main feature of this design is that consensus tracking can be achieved using only input-output data of each agent. The effectiveness of the proposed design is verified by simulation examples.

  7. Taiwanese Dermatological Association consensus for the definition, classification, diagnosis, and management of urticaria.

    Science.gov (United States)

    Chung, Wen-Hung; Chu, Chia-Yu; Huang, Yu-Huei; Wang, Wei-Ming; Yang, Chih-Hsun; Tsai, Tsen-Fang

    2016-11-01

    This report describes the 2014 consensus of the Taiwanese Dermatological Association regarding the definition, classification, diagnosis, and management of urticaria. This consensus is distributed to practices throughout Taiwan to provide recommendations for diagnostic and therapeutic approaches for common subtypes of urticaria, in order to improve the quality of life of urticaria patients. The consensus, thus, serves as an important reference for dermatologists throughout Taiwan. All the consensus contents were voted on by the participating dermatologists, with approval by no less than 75% being required for inclusion. The consensus provides a comprehensive overview of urticaria, including recent advances in identifying its causes and the processes by which it develops. All the consensus meeting attendees agreed to a definition of urticaria, which states that it is characterized by the sudden appearance of wheals (also known as hives), angioedema, or both. Most of the experts (16 out of 19, or 84.2%) agreed that chronic urticaria is defined as the sudden occurrence of wheals and/or angioedema for a period of ≥ 6 weeks. In addition, the consensus attendees also approved the Urticaria Activity Score system or the Urticaria Activity Score for 7 days system as the recommended method for assessing disease activity in spontaneous urticaria. It was also determined that the treatment goal for patients with any form of urticaria should be complete cessation of suffering from all urticaria symptoms. The recommended treatment algorithms for chronic spontaneous urticaria and acute urticaria were finally proposed and approved by 100% (19/19) and 84.2% (16/19) of the consensus attendees, respectively. Copyright © 2015. Published by Elsevier B.V.

  8. Distributed operating systems

    NARCIS (Netherlands)

    Mullender, Sape J.

    1987-01-01

    In the past five years, distributed operating systems research has gone through a consolidation phase. On a large number of design issues there is now considerable consensus between different research groups. In this paper, an overview of recent research in distributed systems is given. In turn, th

  9. Overlapping community detection using weighted consensus clustering

    Indian Academy of Sciences (India)

    LINTAO YANG; ZETAI YU; JING QIAN; SHOUYIN LIU

    2016-10-01

    Many overlapping community detection algorithms have been proposed. Most of them are unstable and behave non-deterministically. In this paper, we use weighted consensus clustering for combining multiple base covers obtained by classic non-deterministic algorithms to improve the quality of the results. We first evaluate a reliability measure for each community in all base covers and assign a proportional weight to each one. Then we redefine the consensus matrix that takes into account not only the common membership of nodes, but also the reliability of the communities. Experimental results on both artificial and real-world networks show that our algorithm can find overlapping communities accurately.

  10. Serving by local consensus in the public service location game

    CERN Document Server

    Sun, Yi-Fan

    2016-01-01

    We discuss the issue of distributed and cooperative decision-making in a network game of public service location. Each node of the network can choose to be a provider of service which is accessible to the provider itself and also to all the neighboring nodes. A node may also choose only to be a consumer, and then it has to pay a tax, and the collected tax is evenly distributed to all the service providers to remedy their cost. If nodes do not communicate with each other but make individual best-response decisions, the system will be trapped in an inefficient situation of high tax level. In this work we investigate a decentralized local-consensus selection mechanism, according to which nodes in need of service recommend their neighbors of highest local impact as candidate servers, and a node may become a server only if all its non-server neighbors give their assent. We demonstrate that this local-consensus mechanism, although only involving information exchange among neighboring nodes, leads to socially effici...

  11. A Consensus on Mantle Potential Temperatures? (Invited)

    Science.gov (United States)

    Putirka, K. D.

    2009-12-01

    Recent publications may indicate a mounting consensus regarding mantle temperatures - an agreement that can be crucial for improving our understanding of mantle dynamics. To compare temperatures at various localities, McKenzie & Bickle (1988) proposed the concept of a mantle potential temperature (Tp) as a reference; Tp is the temperature the mantle would have at the surface, if it ascended along an adiabat without undergoing melting. Perhaps the most precise method to estimate Tp involves estimating the conditions of partial melting, and then correcting for the heat of fusion. The several sources of error include estimation of: a parental liquid, an equilibrium mantle olivine, the degree of partial melting (F), and the depth at which the parental melt is generated. There is also model error inherent to any thermometer. And when correcting for the heat of fusion we assume that we are correcting up to the convective adiabat, but if the parental melt was generated within the conductive lithosphere, Tp will be low. In any case, if we accept that the highest Tp estimates at Hawaii are of most interest (since magmas generated away from a plume centerline will not reflect the full heat content of a high T source), then in spite of these sources of error, recent estimates, published over a span of 10 months by three independent research groups, indicate considerable convergence. At Hawaii maximum Tp values are: 1600 deg. C by Herzberg & Asimow (2008), ca. 1630 deg. C by Lee et al. (2009; their Fig. 2B), and using two slightly different equation sets, 1687 deg. C by Putirka (2008; Geology) and 1660 deg. C by Putirka (2008; RiMG volume 69), yielding an average of 1644±38oC. Similarly, there is convergence for mean Tp at MORs (accepting that MORs are not isothermal; Klein and Langmuir, 1987): Herzberg & Asimow (2008) and Lee et al. (2009) estimate that Tp is ca. 1350 deg. C, and Putirka (2008; Geology) estimates a Tp of 1396 deg. C; these estimates average to 1365±26o

  12. Sampled-Data Consensus of Linear Multi-agent Systems With Packet Losses.

    Science.gov (United States)

    Zhang, Wenbing; Tang, Yang; Huang, Tingwen; Kurths, Jurgen

    2016-08-17

    In this paper, the consensus problem is studied for a class of multi-agent systems with sampled data and packet losses, where random and deterministic packet losses are considered, respectively. For random packet losses, a Bernoulli-distributed white sequence is used to describe packet dropouts among agents in a stochastic way. For deterministic packet losses, a switched system with stable and unstable subsystems is employed to model packet dropouts in a deterministic way. The purpose of this paper is to derive consensus criteria, such that linear multi-agent systems with sampled-data and packet losses can reach consensus. By means of the Lyapunov function approach and the decomposition method, the design problem of a distributed controller is solved in terms of convex optimization. The interplay among the allowable bound of the sampling interval, the probability of random packet losses, and the rate of deterministic packet losses are explicitly derived to characterize consensus conditions. The obtained criteria are closely related to the maximum eigenvalue of the Laplacian matrix versus the second minimum eigenvalue of the Laplacian matrix, which reveals the intrinsic effect of communication topologies on consensus performance. Finally, simulations are given to show the effectiveness of the proposed results.

  13. "Company motivates the miserable": the impact of consensus information on help seeking for psychological problems.

    Science.gov (United States)

    Snyder, C R; Ingram, R E

    1983-11-01

    Based on an attribution theory analysis, it was predicted that normal individuals (people who do not evidence a particular target problem) would be least motivated to seek help for a psychological problem when they believe that the problem is actuarially common (i.e., high consensus). Based on an analysis of how target problem people evaluate their psychological problem, however, it was predicted that such individuals (unlike normal individuals) should be maximally motivated to seek help when they believe that the problem is common. To test these predictions, target problem and normal individuals (high vs. average test anxious females) were given feedback that they possessed a problem (test anxiety). Individuals were then told that their problem was either common, uncommon, or given no consensus information. As predicted, the higher consensus information led to the least help-seeking behavior for the normal individuals and to the most help-seeking behavior for the target problem individuals.

  14. Finite-Time Consensus with a Time-Varying Reference State and Switching Topology

    Directory of Open Access Journals (Sweden)

    Jian-Yong Wang

    2017-01-01

    Full Text Available The finite-time consensus problem in the networks of multiple mobile agents is comprehensively investigated. In order to resolve this problem, a novel nonlinear information exchange protocol is proposed. The proposed protocol ensures that the states of the agents are converged to a weighted-average consensus in finite time if the communication topology is a weighted directed graph with a spanning tree and each strongly connected component is detail-balanced. Furthermore, the proposed protocol is also able to solve the finite-time consensus problem of networks with a switching topology. Finally, computer simulations are presented to demonstrate and validate the effectiveness of the theoretical analysis under the proposed protocol.

  15. Consensus virtual screening approaches to predict protein ligands.

    Science.gov (United States)

    Kukol, Andreas

    2011-09-01

    In order to exploit the advantages of receptor-based virtual screening, namely time/cost saving and specificity, it is important to rely on algorithms that predict a high number of active ligands at the top ranks of a small molecule database. Towards that goal consensus methods combining the results of several docking algorithms were developed and compared against the individual algorithms. Furthermore, a recently proposed rescoring method based on drug efficiency indices was evaluated. Among AutoDock Vina 1.0, AutoDock 4.2 and GemDock, AutoDock Vina was the best performing single method in predicting high affinity ligands from a database of known ligands and decoys. The rescoring of predicted binding energies with the water/octanol partition coefficient did not lead to an improvement averaged over ten receptor targets. Various consensus algorithms were investigated and a simple combination of AutoDock and AutoDock Vina results gave the most consistent performance that showed early enrichment of known ligands for all receptor targets investigated. In case a number of ligands is known for a specific target, every method proposed in this study should be evaluated. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  16. Análisis metodológico de la distribución espacial de la precipitación y la estimación media diaria Methodological analysis of the spatial distribution of rainfall and the average daily stimation

    Directory of Open Access Journals (Sweden)

    Mauro Íñiguez Covarrubias

    2011-02-01

    Full Text Available El objetivo del trabajo consistió en mostrar un análisis metodológico geoestadístico, para generar un patrón espacial de la lluvia, asociado a la precipitación media diaria. Caracterizar y conocer la distribución espacial de la precipitación, también conocida como "campo de tormenta" y asociarla a un modelo de distribución o sustituirla por una precipitación media por métodos convencionales, es un reto importante en estudios de las ciencias del agua. La metodología propuesta requiere de la construcción de un variograma, elaborado por un ajuste de datos experimentales de un campo de tormenta, que sirva como base para generar la distribución espacial de la lluvia con la aplicación del método geoestadístico del "krigeado". Esto permite determinar la precipitación media diaria de una cuenca hidrográfica. Los resultados muestran que es posible obtener una función que relacione la lluvia media con el campo de tormenta, mediante los parámetros α y β del variograma ajustado a un modelo esférico. Para validar la aplicación de la metodología se analizaron varios eventos, aquí se presentan dos eventos de precipitación observada en la cuenca del río Juchipila, y río Calvillo, entre los estados de Aguascalientes y Zacatecas. Los resultados muestran una relación única de la lluvia media diaria con la distribución espacial, representada por el campo de tormenta. Asimismo, se encontró que el valor óptimo de la función es mínimo al compararlo con los resultados obtenidos por cuatro métodos convencionales: promedio aritmético, polígonos de Thiessen, método de isoyetas y método de krigeado lineal.The aim of the study was to show a geostatistical methodological analysis to create a spatial pattern of rain, related to average daily rainfall. Defining and knowing the spatial distribution of rainfall, also known as the "storm field" and related to a distribution model, or replacing it to an average rainfall using conventional

  17. Introduction: experts and consensus in social science

    NARCIS (Netherlands)

    M. Boumans; C. Martini

    2014-01-01

    The ideals of science as objectivity and consensus are - unsurprisingly - not so easy to attain in scientific practice. Science is ultimately a product of individual scientists with their own personal backgrounds and experiences, and there is no unique methodology to de-personalize and objectify kno

  18. ESMO consensus conference on malignant lymphoma

    DEFF Research Database (Denmark)

    Ladetto, M; Buske, C; Hutchings, M;

    2016-01-01

    into three working groups; each group focused on one of these areas in order to address four clinically relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed...

  19. 2016 updated MASCC/ESMO consensus recommendations

    DEFF Research Database (Denmark)

    Roila, Fausto; Warr, David; Hesketh, Paul J

    2017-01-01

    PURPOSE: An update of the recommendations for the prophylaxis of acute and delayed emesis induced by moderately emetogenic chemotherapy published after the last MASCC/ESMO antiemetic consensus conference in 2009 has been carried out. METHODS: A systematic literature search using PubMed from Janua...

  20. Beyond the Consensus View: Whole Science

    Science.gov (United States)

    Allchin, Douglas

    2017-01-01

    The "consensus view" on the nature of science (NOS) is now outmoded. To help frame an enduring alternative, one should attend first to the "why" of NOS education. Functional, or civic, scientific literacy is foundational. Acknowledging a need for consumers and citizens to assess the reliability of scientific claims in personal…

  1. 3rd BRAZILIAN CONSENSUS ON Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Luiz Gonzaga Coelho

    2013-04-01

    Full Text Available Significant progress has been obtained since the Second Brazilian Consensus Conference on Helicobacter pylori Infection held in 2004, in São Paulo, SP, Brazil, and justify a third meeting to establish updated guidelines on the current management of H. pylori infection. The Third Brazilian Consensus Conference on H pylori Infection was organized by the Brazilian Nucleus for the Study of Helicobacter, a Department of the Brazilian Federation of Gastroenterology and took place on April 12-15, 2011, in Bento Gonçalves, RS, Brazil. Thirty-one delegates coming from the five Brazilian regions and one international guest, including gastroenterologists, pathologists, epidemiologists, and pediatricians undertook the meeting. The participants were allocated in one of the five main topics of the meeting: H pylori, functional dyspepsia and diagnosis; H pylori and gastric cancer; H pylori and other associated disorders; H pylori treatment and retreatment; and, epidemiology of H pylori infection in Brazil. The results of each subgroup were submitted to a final consensus voting to all participants. Relevant data were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. Seventy per cent and more votes were considered as acceptance for the final statement. This article presents the main recommendations and conclusions to guide Brazilian doctors involved in the management of H pylori infection.

  2. 3rd Brazilian Consensus on Helicobacter pylori.

    Science.gov (United States)

    Coelho, Luiz Gonzaga; Maguinilk, Ismael; Zaterka, Schlioma; Parente, José Miguel; do Carmo Friche Passos, Maria; Moraes-Filho, Joaquim Prado P

    2013-04-01

    Signicant progress has been obtained since the Second Brazilian Consensus Conference on Helicobacter pylori Infection held in 2004, in São Paulo, SP, Brazil, and justify a third meeting to establish updated guidelines on the current management of H. pylori infection. The Third Brazilian Consensus Conference on H pylori Infection was organized by the Brazilian Nucleus for the Study of Helicobacter, a Department of the Brazilian Federation of Gastroenterology and took place on April 12-15, 2011, in Bento Gonçalves, RS, Brazil. Thirty-one delegates coming from the five Brazilian regions and one international guest, including gastroenterologists, pathologists, epidemiologists, and pediatricians undertook the meeting. The participants were allocated in one of the five main topics of the meeting: H pylori, functional dyspepsia and diagnosis; H pylori and gastric cancer; H pylori and other associated disorders; H pylori treatment and retreatment; and, epidemiology of H pylori infection in Brazil. The results of each subgroup were submitted to a final consensus voting to all participants. Relevant data were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. Seventy per cent and more votes were considered as acceptance for the final statement. This article presents the main recommendations and conclusions to guide Brazilian doctors involved in the management of H pylori infection.

  3. Consensus over peri-implantaire infecties

    NARCIS (Netherlands)

    van Winkelhoff, A J

    2010-01-01

    In 2008, in a workshop of the European Federation on Periodontology, a consensus was reached concerning oral peri-implant infections on the basis of the state of the art in the relevant sciences. Important conclusions were that peri-implant mucositis occurs in 80% of subjects with oral implants, and

  4. The Overreliance of Accreditors on Consensus Standards.

    Science.gov (United States)

    Murray, Frank B.

    2001-01-01

    Argues that the legitimacy of accreditation in teacher education is rooted in political consensus, power, and scholarship. Because these roots are fragile, there is no accepted concept of educational malpractice. The legitimacy of accreditation should be rooted in scholarly evidence that the program has fulfilled the claim that its graduates are…

  5. Judicial Deference Allows European Consensus to Emerge

    DEFF Research Database (Denmark)

    Dothan, Shai

    2017-01-01

    conceived as competing doctrines: the more there is of one, the less there is of another. This paper suggests a novel rationale for the emerging consensus doctrine: the doctrine can allow the ECHR to make good policies by drawing on the independent decision-making of many similar countries. In light of that...

  6. Health Promoting Schools: Consensus, Strategies, and Potential

    Science.gov (United States)

    Macnab, Andrew J.; Gagnon, Faith A.; Stewart, Donald

    2014-01-01

    Purpose: The purpose of this paper is to summarize a consensus statement generated on the current challenges, strategies, and potential of health promoting schools (HPS) at a 2011 colloquium at the Stellenbosch Institute for Advanced Study where 40 people from five continents came together to share their global and regional experience surrounding…

  7. Introduction: experts and consensus in social science

    NARCIS (Netherlands)

    Boumans, M.; Martini, C.; Martini, C.; Boumans, M.

    2014-01-01

    The ideals of science as objectivity and consensus are - unsurprisingly - not so easy to attain in scientific practice. Science is ultimately a product of individual scientists with their own personal backgrounds and experiences, and there is no unique methodology to de-personalize and objectify

  8. Consensus over peri-implantaire infecties

    NARCIS (Netherlands)

    van Winkelhoff, A J

    2010-01-01

    In 2008, in a workshop of the European Federation on Periodontology, a consensus was reached concerning oral peri-implant infections on the basis of the state of the art in the relevant sciences. Important conclusions were that peri-implant mucositis occurs in 80% of subjects with oral implants, and

  9. Adult Asthma Consensus Guidelines Update 2003

    Directory of Open Access Journals (Sweden)

    Catherine Lemière

    2004-01-01

    Full Text Available BACKGROUND: Several sets of Canadian guidelines for the diagnosis and management of asthma have been published over the past 15 years. Since the last revision of the 1999 Canadian Asthma Consensus Report, important new studies have highlighted the need to incorporate new information into the asthma guidelines.

  10. Consensus at the Heart of Division: Commentary on Norton and Ariely (2011).

    Science.gov (United States)

    Dunn, Elizabeth W; Buchtel, Emma E; Aknin, Lara B

    2011-01-01

    We argue that seemingly deep-seated partisan divisions may be built on a foundation of surprising consensus, not only in terms of the wealth distributions that people prefer (Norton & Ariely, 2011, this issue), but also in the gut-level moral reactions and beliefs about money and happiness that may underlie those preferences.

  11. Performance of a Distributed Stochastic Approximation Algorithm

    CERN Document Server

    Bianchi, Pascal; Hachem, Walid

    2012-01-01

    In this paper, a distributed stochastic approximation algorithm is studied. Applications of such algorithms include decentralized estimation, optimization, control or computing. The algorithm consists in two steps: a local step, where each node in a network updates a local estimate using a stochastic approximation algorithm with decreasing step size, and a gossip step, where a node computes a local weighted average between its estimates and those of its neighbors. Convergence of the estimates toward a consensus is established under weak assumptions. The approach relies on two main ingredients: the existence of a Lyapunov function for the mean field in the agreement subspace, and a contraction property of the random matrices of weights in the subspace orthogonal to the agreement subspace. A second order analysis of the algorithm is also performed under the form of a Central Limit Theorem. The Polyak-averaged version of the algorithm is also considered.

  12. On the General Consensus Protocol in Multiagent Networks with Double-Integrator Dynamics and Coupling Time Delay

    Directory of Open Access Journals (Sweden)

    Tao Dong

    2013-01-01

    Full Text Available This paper considers the problem of the convergence of the consensus algorithm for multiple agents in a directed network where each agent is governed by double-integrator dynamics and coupling time delay. The advantage of this protocol is that almost all the existing linear local interaction consensus protocols can be considered as special cases of the present paper. By combining algebraic graph theory and matrix theory and studying the distribution of the eigenvalues of the associated characteristic equation, some necessary and sufficient conditions are derived for reaching the second-order consensus. Finally, an illustrative example is also given to support the theoretical results.

  13. Expert consensus document: A consensus on the medical treatment of acromegaly.

    Science.gov (United States)

    Giustina, Andrea; Chanson, Philippe; Kleinberg, David; Bronstein, Marcello D; Clemmons, David R; Klibanski, Anne; van der Lely, Aart J; Strasburger, Christian J; Lamberts, Steven W; Ho, Ken K Y; Casanueva, Felipe F; Melmed, Shlomo

    2014-04-01

    In March 2013, the Acromegaly Consensus Group met to revise and update guidelines for the medical treatment of acromegaly. The meeting comprised experts skilled in the medical management of acromegaly. The group considered treatment goals covering biochemical, clinical and tumour volume outcomes, and the place in guidelines of somatostatin receptor ligands, growth hormone receptor antagonists and dopamine agonists, and alternative modalities for treatment including combination therapy and novel treatments. This document represents the conclusions of the workshop consensus.

  14. Learning Gene Regulatory Networks Computationally from Gene Expression Data Using Weighted Consensus

    KAUST Repository

    Fujii, Chisato

    2015-04-16

    Gene regulatory networks analyze the relationships between genes allowing us to un- derstand the gene regulatory interactions in systems biology. Gene expression data from the microarray experiments is used to obtain the gene regulatory networks. How- ever, the microarray data is discrete, noisy and non-linear which makes learning the networks a challenging problem and existing gene network inference methods do not give consistent results. Current state-of-the-art study uses the average-ranking-based consensus method to combine and average the ranked predictions from individual methods. However each individual method has an equal contribution to the consen- sus prediction. We have developed a linear programming-based consensus approach which uses learned weights from linear programming among individual methods such that the methods have di↵erent weights depending on their performance. Our result reveals that assigning di↵erent weights to individual methods rather than giving them equal weights improves the performance of the consensus. The linear programming- based consensus method is evaluated and it had the best performance on in silico and Saccharomyces cerevisiae networks, and the second best on the Escherichia coli network outperformed by Inferelator Pipeline method which gives inconsistent results across a wide range of microarray data sets.

  15. Consensus Through Conversation How to Achieve High-Commitment Decisions

    CERN Document Server

    Dressler, Larry

    2006-01-01

    Facilitation expert Larry Dressler's Consensus Through Conversation is a guide for the effective facilitation and practice of one of business's most popular - but most widely misunderstood - decision-making models: consensus.

  16. International Multispecialty Consensus on How to Evaluate Ultrasound Competence

    DEFF Research Database (Denmark)

    Tolsgaard, Martin G.; Todsen, Tobias; Sorensen, Jette L.

    2013-01-01

    To achieve international consensus across multiple specialties on a generic ultrasound rating scale using a Delphi technique.......To achieve international consensus across multiple specialties on a generic ultrasound rating scale using a Delphi technique....

  17. Managing Carious Lesions: Consensus Recommendations on Carious Tissue Removal

    NARCIS (Netherlands)

    Schwendicke, F.; Frencken, J.E.; Bjorndal, L.; Maltz, M.; Manton, D.J.; Ricketts, D.; Van Landuyt, K.; Banerjee, A.; Campus, G.; Domejean, S.; Fontana, M.; Leal, S.; Lo, E.; Machiulskiene, V.; Schulte, A.; Splieth, C.; Zandona, A.F.; Innes, N.P.

    2016-01-01

    The International Caries Consensus Collaboration undertook a consensus process and here presents clinical recommendations for carious tissue removal and managing cavitated carious lesions, including restoration, based on texture of demineralized dentine. Dentists should manage the disease dental

  18. Core Competencies of the Certified Pediatric Doctor of Chiropractic: Results of a Delphi Consensus Process.

    Science.gov (United States)

    Hewitt, Elise; Hestbaek, Lise; Pohlman, Katherine A

    2016-04-01

    An outline of the minimum core competencies expected from a certified pediatric doctor of chiropractic was developed using a Delphi consensus process. The initial set of seed statements and substatements was modeled on competency documents used by organizations that oversee chiropractic and medical education. These statements were distributed to the Delphi panel, reaching consensus when 80% of the panelists approved each segment. The panel consisted of 23 specialists in chiropractic pediatrics (14 females) from across the broad spectrum of the chiropractic profession. Sixty-one percent of panelists had postgraduate pediatric certifications or degrees, 39% had additional graduate degrees, and 74% were faculty at a chiropractic institution and/or in a postgraduate pediatrics program. The panel were initially given 10 statements with related substatements formulated by the study's steering committee. On all 3 rounds of the Delphi process the panelists reached consensus; however, multiple rounds occurred to incorporate the valuable qualitative feedback received.

  19. Emergence of Consensus in a Multi-Robot Network: from Abstract Models to Empirical Validation

    CERN Document Server

    Trianni, Vito; Reina, Andreagiovanni; Baronchelli, Andrea

    2016-01-01

    Consensus dynamics in decentralised multiagent systems are subject to intense studies, and several different models have been proposed and analysed. Among these, the naming game stands out for its simplicity and applicability to a wide range of phenomena and applications, from semiotics to engineering. Despite the wide range of studies available, the implementation of theoretical models in real distributed systems is not always straightforward, as the physical platform imposes several constraints that may have a bearing on the consensus dynamics. In this paper, we investigate the effects of an implementation of the naming game for the kilobot robotic platform, in which we consider concurrent execution of games and physical interferences. Consensus dynamics are analysed in the light of the continuously evolving communication network created by the robots, highlighting how the different regimes crucially depend on the robot density and on their ability to spread widely in the experimental arena. We find that ph...

  20. Robust consensus tracking control for multiagent systems with initial state shifts, disturbances, and switching topologies.

    Science.gov (United States)

    Meng, Deyuan; Jia, Yingmin; Du, Junping

    2015-04-01

    This paper deals with the consensus tracking control issues of multiagent systems and aims to solve them as accurately as possible over a finite time interval through an iterative learning approach. Based on the iterative rule, distributed algorithms are proposed for every agent using its nearest neighbor knowledge, for which the robustness problem is addressed against initial state shifts, disturbances, and switching topologies. These uncertainties are dynamically changing not only along the time axis but also the iteration axis. It is shown that the matrix norm conditions can be developed to achieve the convergence of the considered consensus tracking objectives, for which necessary and sufficient conditions are presented in terms of linear matrix inequalities to guarantee their feasibility in the sense of the spectral norm. Furthermore, simulation examples are given to illustrate the effectiveness and robustness of the obtained consensus tracking results.

  1. International Consensus for ultrasound lesions in gout

    DEFF Research Database (Denmark)

    Gutierrez, Marwin; Schmidt, Wolfgang A; Thiele, Ralf G

    2015-01-01

    elementary lesions. A group of 20 images was displayed twice to evaluate intra-reader reliability. RESULTS: A total of 32 participants responded to the questionnaires. Good agreement (>80%) was obtained for US definitions on DC, tophus, aggregates and erosion in the Delphi exercise after three rounds......OBJECTIVE: To produce consensus-based definitions of the US elementary lesions in gout and to test their reliability in a web-based exercise. METHODS: The process consisted of two steps. In the first step a written Delphi questionnaire was developed from a systematic literature review and expert....... The reliability on images showed inter-reader κ values for DC, tophus, aggregates, erosion findings of 0.98, 0.71, 0.54 and 0.85, respectively. The mean intra-reader κ values were also acceptable: 0.93, 0.78, 0.65 and 0.78, respectively. CONCLUSION: This, the first consensus-based US definition of elementary...

  2. Leader-Following Consensus of Nonlinear Multiagent Systems With Stochastic Sampling.

    Science.gov (United States)

    He, Wangli; Zhang, Biao; Han, Qing-Long; Qian, Feng; Kurths, Jurgen; Cao, Jinde

    2017-02-01

    This paper is concerned with sampled-data leader-following consensus of a group of agents with nonlinear characteristic. A distributed consensus protocol with probabilistic sampling in two sampling periods is proposed. First, a general consensus criterion is derived for multiagent systems under a directed graph. A number of results in several special cases without transmittal delays or with the deterministic sampling are obtained. Second, a dimension-reduced condition is obtained for multiagent systems under an undirected graph. It is shown that the leader-following consensus problem with stochastic sampling can be transferred into a master-slave synchronization problem with only one master system and two slave systems. The problem solving is independent of the number of agents, which greatly facilitates its application to large-scale networked agents. Third, the network design issue is further addressed, demonstrating the positive and active roles of the network structure in reaching consensus. Finally, two examples are given to verify the theoretical results.

  3. Police suicide research: conflict and consensus.

    Science.gov (United States)

    Violanti, John M

    2008-01-01

    Despite new frontiers in suicide research over the past ten years, police suicide remains a difficult, persistent, and controversial problem. Controversy appears to focus on the accuracy and validity of police suicide rates, but other controversies exist as well. This is likely due to studies that are methodologically flawed, incomplete, or specific to limited geographic areas. The objective of this paper is to review issues related to both conflicts and consensus on police suicide.

  4. Pragmatism and Political Pluralism - Consensus and Pluralism

    OpenAIRE

    Michele Marsonet

    2015-01-01

    A pragmatist thinker like Nicholas Rescher deems the idea that social harmony must be predicated in consensus to be both dangerous and misleading. An essential problem of our time is the creation of political and social institutions that enable people to live together in peaceful and productive ways, despite the presence of not eliminable disagreements about theoretical and practical issues. Such remarks, in turn, strictly recall the “practical” impossibility of settling philosophical dispute...

  5. Sarcopenia: European consensus on definition and diagnosis

    OpenAIRE

    Alfonso J Cruz-Jentoft; Baeyens, Jean Pierre; Jürgen M Bauer; Boirie, Yves; Cederholm, Tommy; Landi, Francesco; Martin, Finbarr C; Michel, Jean-Pierre; Rolland, Yves; Schneider, Stéphane M; Topinková, Eva; Vandewoude, Maurits; Zamboni, Mauro

    2010-01-01

    The European Working Group on Sarcopenia in Older People (EWGSOP) developed a practical clinical definition and consensus diagnostic criteria for age-related sarcopenia. EWGSOP included representatives from four participant organisations, i.e. the European Geriatric Medicine Society, the European Society for Clinical Nutrition and Metabolism, the International Association of Gerontology and Geriatrics—European Region and the International Association of Nutrition and Aging. These organisation...

  6. A Self-Categorization Explanation for Opinion Consensus Perceptions

    Science.gov (United States)

    Zhang, Jinguang; Reid, Scott A.

    2013-01-01

    The public expression of opinions (and related communicative activities) hinges upon the perception of opinion consensus. Current explanations for opinion consensus perceptions typically focus on egocentric and other biases, rather than functional cognitions. Using self-categorization theory we showed that opinion consensus perceptions flow from…

  7. 7 CFR 1209.12 - On average.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false On average. 1209.12 Section 1209.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS....12 On average. On average means a rolling average of production or imports during the last two...

  8. Consensus contact prediction by linear programming.

    Science.gov (United States)

    Gao, Xin; Bu, Dongbo; Li, Shuai Cheng; Li, Ming; Xu, Jinbo

    2007-01-01

    Protein inter-residue contacts are of great use for protein structure determination or prediction. Recent CASP events have shown that a few accurately predicted contacts can help improve both computational efficiency and prediction accuracy of the ab inito folding methods. This paper develops an integer linear programming (ILP) method for consensus-based contact prediction. In contrast to the simple "majority voting" method assuming that all the individual servers are equal and independent, our method evaluates their correlations using the maximum likelihood method and constructs some latent independent servers using the principal component analysis technique. Then, we use an integer linear programming model to assign weights to these latent servers in order to maximize the deviation between the correct contacts and incorrect ones; our consensus prediction server is the weighted combination of these latent servers. In addition to the consensus information, our method also uses server-independent correlated mutation (CM) as one of the prediction features. Experimental results demonstrate that our contact prediction server performs better than the "majority voting" method. The accuracy of our method for the top L/5 contacts on CASP7 targets is 73.41%, which is much higher than previously reported studies. On the 16 free modeling (FM) targets, our method achieves an accuracy of 37.21%.

  9. Bivariate copulas on the exponentially weighted moving average control chart

    Directory of Open Access Journals (Sweden)

    Sasigarn Kuvattana

    2016-10-01

    Full Text Available This paper proposes four types of copulas on the Exponentially Weighted Moving Average (EWMA control chart when observations are from an exponential distribution using a Monte Carlo simulation approach. The performance of the control chart is based on the Average Run Length (ARL which is compared for each copula. Copula functions for specifying dependence between random variables are used and measured by Kendall’s tau. The results show that the Normal copula can be used for almost all shifts.

  10. A precise measurement of the average b hadron lifetime

    CERN Document Server

    Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Garrido, L; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Meinhard, H; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Stierlin, U; Saint-Denis, R; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; Bloch-Devaux, B; Colas, P; Duarte, H; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Rosowsky, A; Roussarie, A; Schuller, J P; Schwindling, J; Si Mohand, D; Trabelsi, A; Vallage, B; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, P; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1996-01-01

    An improved measurement of the average b hadron lifetime is performed using a sample of 1.5 million hadronic Z decays, collected during the 1991-1993 runs of ALEPH, with the silicon vertex detector fully operational. This uses the three-dimensional impact parameter distribution of lepton tracks coming from semileptonic b decays and yields an average b hadron lifetime of 1.533 \\pm 0.013 \\pm 0.022 ps.

  11. On the average uncertainty for systems with nonlinear coupling

    Science.gov (United States)

    Nelson, Kenric P.; Umarov, Sabir R.; Kon, Mark A.

    2017-02-01

    The increased uncertainty and complexity of nonlinear systems have motivated investigators to consider generalized approaches to defining an entropy function. New insights are achieved by defining the average uncertainty in the probability domain as a transformation of entropy functions. The Shannon entropy when transformed to the probability domain is the weighted geometric mean of the probabilities. For the exponential and Gaussian distributions, we show that the weighted geometric mean of the distribution is equal to the density of the distribution at the location plus the scale (i.e. at the width of the distribution). The average uncertainty is generalized via the weighted generalized mean, in which the moment is a function of the nonlinear source. Both the Rényi and Tsallis entropies transform to this definition of the generalized average uncertainty in the probability domain. For the generalized Pareto and Student's t-distributions, which are the maximum entropy distributions for these generalized entropies, the appropriate weighted generalized mean also equals the density of the distribution at the location plus scale. A coupled entropy function is proposed, which is equal to the normalized Tsallis entropy divided by one plus the coupling.

  12. Consensus-ADMM for General Quadratically Constrained Quadratic Programming

    Science.gov (United States)

    Huang, Kejun; Sidiropoulos, Nicholas D.

    2016-10-01

    Non-convex quadratically constrained quadratic programming (QCQP) problems have numerous applications in signal processing, machine learning, and wireless communications, albeit the general QCQP is NP-hard, and several interesting special cases are NP-hard as well. This paper proposes a new algorithm for general QCQP. The problem is first reformulated in consensus optimization form, to which the alternating direction method of multipliers (ADMM) can be applied. The reformulation is done in such a way that each of the sub-problems is a QCQP with only one constraint (QCQP-1), which is efficiently solvable irrespective of (non-)convexity. The core components are carefully designed to make the overall algorithm more scalable, including efficient methods for solving QCQP-1, memory efficient implementation, parallel/distributed implementation, and smart initialization. The proposed algorithm is then tested in two applications: multicast beamforming and phase retrieval. The results indicate superior performance over prior state-of-the-art methods.

  13. Newly Exerted T Cell Pressures on Mutated Epitopes following Transmission Help Maintain Consensus HIV-1 Sequences.

    Directory of Open Access Journals (Sweden)

    Emily M Eriksson

    Full Text Available CD8+ T cells are important for HIV-1 virus control, but are also a major contributing factor that drives HIV-1 virus sequence evolution. Although HIV-1 cytotoxic T cell (CTL escape mutations are a common aspect during HIV-1 infection, less is known about the importance of T cell pressure in reversing HIV-1 virus back to a consensus sequences. In this study we aimed to assess the frequency with which reversion of transmitted mutations in T cell epitopes were associated with T cell responses to the mutation. This study included 14 HIV-1 transmission pairs consisting of a 'source' (virus-donor and a 'recipient' (newly infected individual. Non-consensus B sequence amino acids (mutations in T cell epitopes in HIV-1 gag regions p17, p24, p2 and p7 were identified in each pair and transmission of mutations to the recipient was verified with population viral sequencing. Longitudinal analyses of the recipient's viral sequence were used to identify whether reversion of mutations back to the consensus B sequence occurred. Autologous 12-mer peptides overlapping by 11 were synthesized, representing the sequence region surrounding each reversion and longitudinal analysis of T cell responses to source-derived mutated and reverted epitopes were assessed. We demonstrated that mutations in the source were frequently transmitted to the new host and on an average 17 percent of mutated epitopes reverted to consensus sequence in the recipient. T cell responses to these mutated epitopes were detected in 7 of the 14 recipients in whom reversion occurred. Overall, these findings indicate that transmitted non-consensus B epitopes are frequently immunogenic in HLA-mismatched recipients and new T cell pressures to T cell escape mutations following transmission play a significant role in maintaining consensus HIV-1 sequences.

  14. Unbiased Cultural Transmission in Time-Averaged Archaeological Assemblages

    CERN Document Server

    Madsen, Mark E

    2012-01-01

    Unbiased models are foundational in the archaeological study of cultural transmission. Applications have as- sumed that archaeological data represent synchronic samples, despite the accretional nature of the archaeological record. I document the circumstances under which time-averaging alters the distribution of model predictions. Richness is inflated in long-duration assemblages, and evenness is "flattened" compared to unaveraged samples. Tests of neutrality, employed to differentiate biased and unbiased models, suffer serious problems with Type I error under time-averaging. Finally, the time-scale over which time-averaging alters predictions is determined by the mean trait lifetime, providing a way to evaluate the impact of these effects upon archaeological samples.

  15. Consensus Formation in Science Modeled by Aggregated Bibliographic Coupling

    DEFF Research Database (Denmark)

    Nicolaisen, Jeppe; Frandsen, Tove Faber

    2012-01-01

    Abstract: The level of consensus in science has traditionally been measured by a number of different methods. The variety is important as each method measures different aspects of science and consensus. Citation analytical studies have previously measured the level of consensus using the scientific...... journal as their unit of analysis. To produce a more fine grained citation analysis one needs to study consensus formation on an even more detailed level – i.e. the scientific document or article. To do so, we have developed a new technique that measures consensus by aggregated bibliographic couplings...

  16. Sampled-data-based consensus and containment control of multiple harmonic oscillators: A motion-planning approach

    Science.gov (United States)

    Liu, Yongfang; Zhao, Yu; Chen, Guanrong

    2016-11-01

    This paper studies the distributed consensus and containment problems for a group of harmonic oscillators with a directed communication topology. First, for consensus without a leader, a class of distributed consensus protocols is designed by using motion planning and Pontryagin's principle. The proposed protocol only requires relative information measurements at the sampling instants, without requiring information exchange over the sampled interval. By using stability theory and the properties of stochastic matrices, it is proved that the distributed consensus problem can be solved in the motion planning framework. Second, for the case with multiple leaders, a class of distributed containment protocols is developed for followers such that their positions and velocities can ultimately converge to the convex hull formed by those of the leaders. Compared with the existing consensus algorithms, a remarkable advantage of the proposed sampled-data-based protocols is that the sampling periods, communication topologies and control gains are all decoupled and can be separately designed, which relaxes many restrictions in controllers design. Finally, some numerical examples are given to illustrate the effectiveness of the analytical results.

  17. A high-density consensus map of barley linking DArT markers to SSR, RFLP and STS loci and agricultural traits

    Directory of Open Access Journals (Sweden)

    Wang Junping

    2006-08-01

    Full Text Available Abstract Background Molecular marker technologies are undergoing a transition from largely serial assays measuring DNA fragment sizes to hybridization-based technologies with high multiplexing levels. Diversity Arrays Technology (DArT is a hybridization-based technology that is increasingly being adopted by barley researchers. There is a need to integrate the information generated by DArT with previous data produced with gel-based marker technologies. The goal of this study was to build a high-density consensus linkage map from the combined datasets of ten populations, most of which were simultaneously typed with DArT and Simple Sequence Repeat (SSR, Restriction Enzyme Fragment Polymorphism (RFLP and/or Sequence Tagged Site (STS markers. Results The consensus map, built using a combination of JoinMap 3.0 software and several purpose-built perl scripts, comprised 2,935 loci (2,085 DArT, 850 other loci and spanned 1,161 cM. It contained a total of 1,629 'bins' (unique loci, with an average inter-bin distance of 0.7 ± 1.0 cM (median = 0.3 cM. More than 98% of the map could be covered with a single DArT assay. The arrangement of loci was very similar to, and almost as optimal as, the arrangement of loci in component maps built for individual populations. The locus order of a synthetic map derived from merging the component maps without considering the segregation data was only slightly inferior. The distribution of loci along chromosomes indicated centromeric suppression of recombination in all chromosomes except 5H. DArT markers appeared to have a moderate tendency toward hypomethylated, gene-rich regions in distal chromosome areas. On the average, 14 ± 9 DArT loci were identified within 5 cM on either side of SSR, RFLP or STS loci previously identified as linked to agricultural traits. Conclusion Our barley consensus map provides a framework for transferring genetic information between different marker systems and for deploying DArT markers in

  18. International consensus on ANA patterns (ICAP): the bumpy road towards a consensus on reporting ANA results.

    Science.gov (United States)

    Damoiseaux, Jan; von Mühlen, Carlos A; Garcia-De La Torre, Ignacio; Carballo, Orlando Gabriel; de Melo Cruvinel, Wilson; Francescantonio, Paulo Luiz Carvalho; Fritzler, Marvin J; Herold, Manfred; Mimori, Tsuneyo; Satoh, Minoru; Andrade, Luis E C; Chan, Edward K L; Conrad, Karsten

    2016-12-01

    The International Consensus on ANA Patterns (ICAP) was initiated as a workshop aiming to thoroughly discuss and achieve consensus regarding the morphological patterns observed in the indirect immunofluorescence assay on HEp-2 cells. One of the topics discussed at the second ICAP workshop, and addressed in this paper, was the harmonization of reporting ANA test results. This discussion centered on the issue if cytoplasmic and mitotic patterns should be reported as positive or negative. This report outlines the issues that impact on two major different reporting methods. Although it was appreciated by all participants that cytoplasmic and mitotic patterns are clinically relevant, implications for existing diagnostic/classification criteria for ANA-associated diseases in particular hampered a final consensus on this topic. Evidently, a more concerted action of all relevant stakeholders is required. Future ICAP workshops may help to facilitate this action.

  19. Level sets of multiple ergodic averages

    CERN Document Server

    Ai-Hua, Fan; Ma, Ji-Hua

    2011-01-01

    We propose to study multiple ergodic averages from multifractal analysis point of view. In some special cases in the symbolic dynamics, Hausdorff dimensions of the level sets of multiple ergodic average limit are determined by using Riesz products.

  20. Developing consensus criteria for sarcopenia: an update.

    Science.gov (United States)

    McLean, Robert R; Kiel, Douglas P

    2015-04-01

    Sarcopenia, the age-related loss of muscle mass and strength, is a major cause of impaired physical function, which contributes to mobility disability, falls and hospitalizations in older adults. Lower muscle mass and strength are also associated with lower bone mineral density and greater risk for osteoporotic fractures. Thus, identification of sarcopenia could be important for fracture prevention as it may help improve fracture risk assessment, and muscle mass and strength can be improved with exercise, even among the frailest older adults. Unfortunately, there are no consensus diagnostic criteria for sarcopenia. Consequently there is no guidance to help clinicians identify older adults with clinically meaningful low muscle mass or weakness. Further, development of novel sarcopenia therapies is hindered not only due to the difficulty in identifying participants for clinical trials, and but also because there are no validated, clinically appropriate endpoints for assessment of treatment efficacy. There is currently a major push to establish a consensus definition of sarcopenia, and recent work holds promise that this goal may be within reach. This article discusses the evolution of the definition of sarcopenia, and focuses on the latest recommended diagnostic criteria proposed by the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project. While these empirically-based cut-points for clinically important low muscle mass and weakness are a significant step forward for the sarcopenia field, important questions remain to be answered before consensus diagnostic criteria can be definitively established. Ongoing work to refine sarcopenia criteria will further advance the field and bring this important contributor to falls, fractures and disability into the mainstream of clinical care and ultimately lead to better quality of life with aging. © 2015 American Society for Bone and Mineral Research.

  1. QSAR study of malonyl-CoA decarboxylase inhibitors using GA-MLR and a new strategy of consensus modeling.

    Science.gov (United States)

    Li, Jiazhong; Lei, Beilei; Liu, Huanxiang; Li, Shuyan; Yao, Xiaojun; Liu, Mancang; Gramatica, Paola

    2008-12-01

    Quantitative structure-activity relationship (QSAR) of a series of structural diverse malonyl-CoA decarboxylase (MCD) inhibitors have been investigated by using the predictive single model as well as the consensus analysis based on a new strategy proposed by us. Self-organizing map (SOM) neural network was employed to divide the whole data set into representative training set and test set. Then a multiple linear regressions (MLR) model population was built based on the theoretical molecular descriptors selected by Genetic Algorithm using the training set. In order to analyze the diversity of these models, multidimensional scaling (MDS) was employed to explore the model space based on the Hamming distance matrix calculated from each two models. In this space, Q(2) (cross-validated R(2)) guided model selection (QGMS) strategy was performed to select submodels. Then consensus modeling was built by two strategies, average consensus model (ACM) and weighted consensus model (WCM), where each submodel had a different weight according to the contribution of model expressed by MLR regression coefficients. The obtained results prove that QGMS is a reliable and practical method to guide the submodel selection in consensus modeling building and our weighted consensus model (WCM) strategy is superior to the simple ACM. 2008 Wiley Periodicals, Inc.

  2. Accurate Switched-Voltage voltage averaging circuit

    OpenAIRE

    金光, 一幸; 松本, 寛樹

    2006-01-01

    Abstract ###This paper proposes an accurate Switched-Voltage (SV) voltage averaging circuit. It is presented ###to compensated for NMOS missmatch error at MOS differential type voltage averaging circuit. ###The proposed circuit consists of a voltage averaging and a SV sample/hold (S/H) circuit. It can ###operate using nonoverlapping three phase clocks. Performance of this circuit is verified by PSpice ###simulations.

  3. Spectral averaging techniques for Jacobi matrices

    CERN Document Server

    del Rio, Rafael; Schulz-Baldes, Hermann

    2008-01-01

    Spectral averaging techniques for one-dimensional discrete Schroedinger operators are revisited and extended. In particular, simultaneous averaging over several parameters is discussed. Special focus is put on proving lower bounds on the density of the averaged spectral measures. These Wegner type estimates are used to analyze stability properties for the spectral types of Jacobi matrices under local perturbations.

  4. The Mexican consensus on probiotics in gastroenterology

    Directory of Open Access Journals (Sweden)

    M.A. Valdovinos

    2017-04-01

    Results and conclusions: Eleven statements on the general concepts of probiotics and 27 statements on the use of probiotics in gastrointestinal diseases in both adults and children were formulated. The consensus group recommends the use of probiotics under the following clinical conditions: the prevention of diarrhea associated with antibiotics, the treatment of acute infectious diarrhea, the prevention of Clostridium difficile infection and necrotizing enterocolitis, the reduction of adverse events from Helicobacter pylori eradication therapy, relief from irritable bowel syndrome symptoms, the treatment of functional constipation in the adult, and the induction and maintenance of remission in patients with ulcerative colitis (UC and pouchitis, and the treatment of covert and overt hepatic encephalopathy.

  5. Consensus Paper: Neuroimmune Mechanisms of Cerebellar Ataxias.

    Science.gov (United States)

    Mitoma, Hiroshi; Adhikari, Keya; Aeschlimann, Daniel; Chattopadhyay, Partha; Hadjivassiliou, Marios; Hampe, Christiane S; Honnorat, Jérôme; Joubert, Bastien; Kakei, Shinji; Lee, Jongho; Manto, Mario; Matsunaga, Akiko; Mizusawa, Hidehiro; Nanri, Kazunori; Shanmugarajah, Priya; Yoneda, Makoto; Yuki, Nobuhiro

    2016-04-01

    In the last few years, a lot of publications suggested that disabling cerebellar ataxias may develop through immune-mediated mechanisms. In this consensus paper, we discuss the clinical features of the main described immune-mediated cerebellar ataxias and address their presumed pathogenesis. Immune-mediated cerebellar ataxias include cerebellar ataxia associated with anti-GAD antibodies, the cerebellar type of Hashimoto's encephalopathy, primary autoimmune cerebellar ataxia, gluten ataxia, Miller Fisher syndrome, ataxia associated with systemic lupus erythematosus, and paraneoplastic cerebellar degeneration. Humoral mechanisms, cell-mediated immunity, inflammation, and vascular injuries contribute to the cerebellar deficits in immune-mediated cerebellar ataxias.

  6. Multiple chemical sensitivity: a 1999 consensus.

    Science.gov (United States)

    1999-01-01

    Consensus criteria for the definition of multiple chemical sensitivity (MCS) were first identified in a 1989 multidisciplinary survey of 89 clinicians and researchers with extensive experience in, but widely differing views of, MCS. A decade later, their top 5 consensus criteria (i.e., defining MCS as [1] a chronic condition [2] with symptoms that recur reproducibly [3] in response to low levels of exposure [4] to multiple unrelated chemicals and [5] improve or resolve when incitants are removed) are still unrefuted in published literature. Along with a 6th criterion that we now propose adding (i.e., requiring that symptoms occur in multiple organ systems), these criteria are all commonly encompassed by research definitions of MCS. Nonetheless, their standardized use in clinical settings is still lacking, long overdue, and greatly needed--especially in light of government studies in the United States, United Kingdom, and Canada that revealed 2-4 times as many cases of chemical sensitivity among Gulf War veterans than undeployed controls. In addition, state health department surveys of civilians in New Mexico and California showed that 2-6%, respectively, already had been diagnosed with MCS and that 16% of the civilians reported an "unusual sensitivity" to common everyday chemicals. Given this high prevalence, as well as the 1994 consensus of the American Lung Association, American Medical Association, U.S. Environmental Protection Agency, and the U.S. Consumer Product Safety Commission that "complaints [of MCS] should not be dismissed as psychogenic, and a thorough workup is essential," we recommend that MCS be formally diagnosed--in addition to any other disorders that may be present--in all cases in which the 6 aforementioned consensus criteria are met and no single other organic disorder (e.g., mastocytosis) can account for all the signs and symptoms associated with chemical exposure. The millions of civilians and tens of thousands of Gulf War veterans who

  7. Avaliação da distribuição de sementes por uma semeadora de anel interno rotativo utilizando média móvel exponencial Proposal of using exponentially weighted moving average for studies about longitudinal distribution of seeds

    Directory of Open Access Journals (Sweden)

    Daniel Albiero

    2012-03-01

    Full Text Available Conceitos de qualidade cada vez mais se tornam essenciais para a sobrevivência da empresa agrícola, pois a importância do aprimoramento das operações agrícolas se faz necessária para a obtenção de resultados viáveis economicamente, ambientamente e socialmente. Uma das dimensões da qualidade é conseguir de conformidade, ou seja, a garantia de execução exata do que foi planejado para atender aos requisitos dos clientes em relação a um determinado produto ou serviço. Os objetivos deste trabalho são avaliar a distribuição longitudinal entre sementes de uma semeadora de anel interno rotativo, e propor a utilização da metodologia estatística da Média Móvel Exponencialmente Ponderada (MMEP como alternativa para o controle de qualidade da semeadura, quando não há normalidade da distribuição dos dados. Os resultados demonstraram que a MMEP é adequada para a avaliação da qualidade da distribuição longitudinal de sementes, pois concordou com os dados apresentados na estatística descritiva, o que lhe credencia para avaliação de distribuições não normais.Quality concepts are essentials for survivor of agricultural companies, therefore, the importancy of improvement of agricultural process is necessary for to get results economically, environmentally and socially viables. One quality dimension is to get a compliance quality, ie, ensure the exact execution than was planned. The subject of this paper is evaluable at longitudinal distribution between seed of a internal ring seeder. The subject of this paper is to evaluate at longitudinal distribution between seed distributed for a internal ring seeder and to propose the use of statistical methodology exponentially weighted moving average (MMEP like alternative for the quality control of seeders, when there is not normality in data. The results showed that the MMEP is adequate for quality evaluation of longitudinal distribution between seeds, as agreed with the data of

  8. 利用△-分布模型法评估调查数据带有极端值的渔业生物的平均资源密度%Estimating the average stock density with dominating large catches based on △-distribution model

    Institute of Scientific and Technical Information of China (English)

    袁兴伟; 姜亚洲; 程家骅

    2011-01-01

    海洋生物的空间分布具有不均匀性,从而造成底拖网调查数据频数分布显著偏斜.偶尔出现的极端值,会直接影响资源密度均值和方差的估计.作者根据东海区渔业资源监测调查数据库中资料,利用△-分布模型法和调查设计法分别估算了2005年夏季的太平洋褶柔鱼Todarodes paci ficus、2007年春季的鳃鱼Engraulis japonicus以及2008年秋季的竹荚鱼Trachurus japonicus 的平均资源密度.结果表明,利用△-分布模型法对3种鱼类资源密度均值的估算值均低于调查设计法,且△-分布模型法对资源密度均值进行估算时的标准误差也相对较小.因此,针时调查数据中出现极端值的情况,如果资源密度对数转换后服从正态分布,那么利用△-分布模型法对资源密度均值进行估算是一种稳健的评估方法,值得在渔业评估上进行推广.%Due to the patchy spatial distribution of marine biota, data collected from bottom trawlers exhibit a skewed distribution with many zero catches and some very large catches.A common problem in the analyses and interpretation of skewed survey data is that, a single immense catch may account for 50% or more of the total catch during the survey.These extreme values not only greatly affect the estimate of the means but also of the variance.Based on the data collected from the bottom trawl survey conducted in the East China Sea,we estimated the average stock density of Todarodes pacificus in summer 2005,Engraulis japonicus in spring 2007, and Trachurus japonicus in autumn 2008 by employing two methods,namely the △-distribution method and the design-based method.The results revealed that the estimators of the means and the standard errors of stock density for the three populations based on the △-distribution were obviously lower than those based on the design-based method.It was concluded that the mean and the standard error would be overestimated using the design

  9. Pareto Principle in Datamining: an Above-Average Fencing Algorithm

    Directory of Open Access Journals (Sweden)

    K. Macek

    2008-01-01

    Full Text Available This paper formulates a new datamining problem: which subset of input space has the relatively highest output where the minimal size of this subset is given. This can be useful where usual datamining methods fail because of error distribution asymmetry. The paper provides a novel algorithm for this datamining problem, and compares it with clustering of above-average individuals.

  10. Average-Time Games on Timed Automata

    OpenAIRE

    Jurdzinski, Marcin; Trivedi, Ashutosh

    2009-01-01

    An average-time game is played on the infinite graph of configurations of a finite timed automaton. The two players, Min and Max, construct an infinite run of the automaton by taking turns to perform a timed transition. Player Min wants to minimise the average time per transition and player Max wants to maximise it. A solution of average-time games is presented using a reduction to average-price game on a finite graph. A direct consequence is an elementary proof of determinacy for average-tim...

  11. Fitness voter model: Damped oscillations and anomalous consensus

    Science.gov (United States)

    Woolcock, Anthony; Connaughton, Colm; Merali, Yasmin; Vazquez, Federico

    2017-09-01

    We study the dynamics of opinion formation in a heterogeneous voter model on a complete graph, in which each agent is endowed with an integer fitness parameter k ≥0 , in addition to its + or - opinion state. The evolution of the distribution of k -values and the opinion dynamics are coupled together, so as to allow the system to dynamically develop heterogeneity and memory in a simple way. When two agents with different opinions interact, their k -values are compared, and with probability p the agent with the lower value adopts the opinion of the one with the higher value, while with probability 1 -p the opposite happens. The agent that keeps its opinion (winning agent) increments its k -value by one. We study the dynamics of the system in the entire 0 ≤p ≤1 range and compare with the case p =1 /2 , in which opinions are decoupled from the k -values and the dynamics is equivalent to that of the standard voter model. When 0 ≤p mean consensus time τ appears to grow logarithmically with the number of agents N , and it is greatly decreased relative to the linear behavior τ ˜N found in the standard voter model. When 1 /2

    consensus by finite-size fluctuations. The approach to the coexistence state is monotonic for 1 /2

    consensus time that scales as τ ˜Nβ , with β ≃1.45 .

  12. Global consensus on keratoconus and ectatic diseases.

    Science.gov (United States)

    Gomes, José A P; Tan, Donald; Rapuano, Christopher J; Belin, Michael W; Ambrósio, Renato; Guell, José L; Malecaze, François; Nishida, Kohji; Sangwan, Virender S

    2015-04-01

    Despite extensive knowledge regarding the diagnosis and management of keratoconus and ectatic corneal diseases, many controversies still exist. For that reason, there is a need for current guidelines for the diagnosis and management of these conditions. This project aimed to reach consensus of ophthalmology experts from around the world regarding keratoconus and ectatic diseases, focusing on their definition, concepts, clinical management, and surgical treatments. The Delphi method was followed with 3 questionnaire rounds and was complemented with a face-to-face meeting. Thirty-six panelists were involved and allocated to 1 of 3 panels: definition/diagnosis, nonsurgical management, or surgical treatment. The level of agreement considered for consensus was two thirds. Numerous agreements were generated in definitions, methods of diagnosing, and management of keratoconus and other ectatic diseases. Nonsurgical and surgical treatments for these conditions, including the use of corneal cross-linking and corneal transplantations, were presented in a stepwise approach. A flowchart describing a logical management sequence for keratoconus was created. This project resulted in definitions, statements, and recommendations for the diagnosis and management of keratoconus and other ectatic diseases. It also provides an insight into the current worldwide treatment of these conditions.

  13. Consensus on biomarkers for neuroendocrine tumour disease

    Science.gov (United States)

    Oberg, Kjell; Modlin, Irvin M; De Herder, Wouter; Pavel, Marianne; Klimstra, David; Frilling, Andrea; Metz, David C; Heaney, Anthony; Kwekkeboom, Dik; Strosberg, Jonathan; Meyer, Timothy; Moss, Steven F; Washington, Kay; Wolin, Edward; Liu, Eric; Goldenring, James

    2016-01-01

    Management of neuroendocrine neoplasia represents a clinical challenge because of its late presentation, lack of treatment options, and limitations in present imaging modalities and biomarkers to guide management. Monoanalyte biomarkers have poor sensitivity, specificity, and predictive ability. A National Cancer Institute summit, held in 2007, on neuroendocrine tumours noted biomarker limitations to be a crucial unmet need in the management of neuroendocrine tumours. A multinational consensus meeting of multidisciplinary experts in neuroendocrine tumours assessed the use of current biomarkers and defined the perquisites for novel biomarkers via the Delphi method. Consensus (at >75%) was achieved for 88 (82%) of 107 assessment questions. The panel concluded that circulating multianalyte biomarkers provide the highest sensitivity and specificity necessary for minimum disease detection and that this type of biomarker had sufficient information to predict treatment effectiveness and prognosis. The panel also concluded that no monoanalyte biomarker of neuroendocrine tumours has yet fulfilled these criteria and there is insufficient information to support the clinical use of miRNA or circulating tumour cells as useful prognostic markers for this disease. The panel considered that trials measuring multianalytes (eg, neuroendocrine gene transcripts) should also identify how such information can optimise the management of patients with neuroendocrine tumours. PMID:26370353

  14. International Consensus On (ICON) Pediatric Asthma

    Science.gov (United States)

    Papadopoulos, N. G.; Arakawa, H.; Carlsen, K.-H.; Custovic, A.; Gern, J.; Lemanske, R.; Le Souef, P.; Makela, M.; Roberts, G.; Wong, G.; Zar, H.; Akdis, C. A.; Bacharier, L. B.; Baraldi, E.; van Bever, H. P.; de Blic, J.; Boner, A.; Burks, W.; Casale, T. B.; Castro-Rodriguez, J. A.; Chen, Y. Z.; El-Gamal, Y. M.; Everard, M. L.; Frischer, T.; Geller, M.; Gereda, J.; Goh, D. Y.; Guilbert, T. W.; Hedlin, G.; Heymann, P. W.; Hong, S. J.; Hossny, E. M.; Huang, J. L.; Jackson, D. J.; de Jongste, J. C.; Kalayci, O.; Khaled, N.; Kling, S.; Kuna, P.; Lau, S.; Ledford, D. K.; Lee, S. I.; Liu, A. H.; Lockey, R. F.; Lodrup-Carlsen, K.; Lotvall, J.; Morikawa, A.; Nieto, A.; Paramesh, H.; Pawankar, R.; Pohunek, P.; Pongracic, J.; Price, D.; Robertson, C.; Rosario, N.; Rossenwasser, L. J.; Sly, P. D.; Stein, R.; Stick, S.; Szefler, S.; Taussig, L. M.; Valovirta, E.; Vichyanond, P.; Wallace, D.; Weinberg, E.; Wennergren, G.; Wildhaber, J.; Zeiger, R. S.

    2015-01-01

    Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. In order to achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with health care professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re-evaluate and fine-tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent from chronic treatment. There is a trend towards considering phenotype specific treatment choices; however this goal has not yet been achieved. PMID:22702533

  15. Frailty Consensus: A Call to Action

    Science.gov (United States)

    Morley, John E.; Vellas, Bruno; van Kan, G. Abellan; Anker, Stefan D.; Bauer, Juergen M.; Bernabei, Roberto; Cesari, Matteo; Chumlea, W.C.; Doehner, Wolfram; Evans, Jonathan; Fried, Linda P.; Guralnik, Jack M.; Katz, Paul R.; Malmstrom, Theodore K.; McCarter, Roger J.; Gutierrez Robledo, Luis M.; Rockwood, Ken; von Haehling, Stephan; Vandewoude, Maurits F.; Walston, Jeremy

    2014-01-01

    Frailty is a clinical state in which there is an increase in an individual’s vulnerability for developing increased dependency and/or mortality when exposed to a stressor. Frailty can occur as the result of a range of diseases and medical conditions. A consensus group consisting of delegates from 6 major international, European, and US societies created 4 major consensus points on a specific form of frailty: physical frailty. Physical frailty is an important medical syndrome. The group defined physical frailty as “a medical syndrome with multiple causes and contributors that is characterized by diminished strength, endurance, and reduced physiologic function that increases an individual’s vulnerability for developing increased dependency and/or death.”Physical frailty can potentially be prevented or treated with specific modalities, such as exercise, protein-calorie supplementation, vitamin D, and reduction of polypharmacy.Simple, rapid screening tests have been developed and validated, such as the simple FRAIL scale, to allow physicians to objectively recognize frail persons.For the purposes of optimally managing individuals with physical frailty, all persons older than 70 years and all individuals with significant weight loss (≥5%) due to chronic disease should be screened for frailty. PMID:23764209

  16. Dialogic Consensus In Clinical Decision-Making.

    Science.gov (United States)

    Walker, Paul; Lovat, Terry

    2016-12-01

    This paper is predicated on the understanding that clinical encounters between clinicians and patients should be seen primarily as inter-relations among persons and, as such, are necessarily moral encounters. It aims to relocate the discussion to be had in challenging medical decision-making situations, including, for example, as the end of life comes into view, onto a more robust moral philosophical footing than is currently commonplace. In our contemporary era, those making moral decisions must be cognizant of the existence of perspectives other than their own, and be attuned to the demands of inter-subjectivity. Applicable to clinical practice, we propose and justify a Habermasian approach as one useful means of achieving what can be described as dialogic consensus. The Habermasian approach builds around, first, his discourse theory of morality as universalizable to all and, second, communicative action as a cooperative search for truth. It is a concrete way to ground the discourse which must be held in complex medical decision-making situations, in its actual reality. Considerations about the theoretical underpinnings of the application of dialogic consensus to clinical practice, and potential difficulties, are explored.

  17. International consensus on (ICON) pediatric asthma.

    Science.gov (United States)

    Papadopoulos, N G; Arakawa, H; Carlsen, K-H; Custovic, A; Gern, J; Lemanske, R; Le Souef, P; Mäkelä, M; Roberts, G; Wong, G; Zar, H; Akdis, C A; Bacharier, L B; Baraldi, E; van Bever, H P; de Blic, J; Boner, A; Burks, W; Casale, T B; Castro-Rodriguez, J A; Chen, Y Z; El-Gamal, Y M; Everard, M L; Frischer, T; Geller, M; Gereda, J; Goh, D Y; Guilbert, T W; Hedlin, G; Heymann, P W; Hong, S J; Hossny, E M; Huang, J L; Jackson, D J; de Jongste, J C; Kalayci, O; Aït-Khaled, N; Kling, S; Kuna, P; Lau, S; Ledford, D K; Lee, S I; Liu, A H; Lockey, R F; Lødrup-Carlsen, K; Lötvall, J; Morikawa, A; Nieto, A; Paramesh, H; Pawankar, R; Pohunek, P; Pongracic, J; Price, D; Robertson, C; Rosario, N; Rossenwasser, L J; Sly, P D; Stein, R; Stick, S; Szefler, S; Taussig, L M; Valovirta, E; Vichyanond, P; Wallace, D; Weinberg, E; Wennergren, G; Wildhaber, J; Zeiger, R S

    2012-08-01

    Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. To achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with healthcare professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re-evaluate and fine-tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent of chronic treatment. There is a trend toward considering phenotype-specific treatment choices; however, this goal has not yet been achieved.

  18. Consensus in networks of mobile communicating agents

    Science.gov (United States)

    Baronchelli, Andrea; Díaz-Guilera, Albert

    2012-01-01

    Populations of mobile and communicating agents describe a vast array of technological and natural systems, ranging from sensor networks to animal groups. Here, we investigate how a group-level agreement may emerge in the continuously evolving network defined by the local interactions of the moving individuals. We adopt a general scheme of motion in two dimensions and we let the individuals interact through the minimal naming game, a prototypical scheme to investigate social consensus. We distinguish different regimes of convergence determined by the emission range of the agents and by their mobility, and we identify the corresponding scaling behaviors of the consensus time. In the same way, we rationalize also the behavior of the maximum memory used during the convergence process, which determines the minimum cognitive/storage capacity needed by the individuals. Overall, we believe that the simple and general model presented in this paper can represent a helpful reference for a better understanding of the behavior of populations of mobile agents.

  19. Consensus in evolving networks of mobile agents

    Science.gov (United States)

    Baronchelli, Andrea; Díaz-Guilera, Albert

    2012-02-01

    Populations of mobile and communicating agents describe a vast array of technological and natural systems, ranging from sensor networks to animal groups. Here, we investigate how a group-level agreement may emerge in the continuously evolving networks defined by the local interactions of the moving individuals. We adopt a general scheme of motion in two dimensions and we let the individuals interact through the minimal naming game, a prototypical scheme to investigate social consensus. We distinguish different regimes of convergence determined by the emission range of the agents and by their mobility, and we identify the corresponding scaling behaviors of the consensus time. In the same way, we rationalize also the behavior of the maximum memory used during the convergence process, which determines the minimum cognitive/storage capacity needed by the individuals. Overall, we believe that the simple and general model presented in this talk can represent a helpful reference for a better understanding of the behavior of populations of mobile agents.

  20. Consensus Paper: Management of Degenerative Cerebellar Disorders

    Science.gov (United States)

    Ilg, W.; Bastian, A. J.; Boesch, S.; Burciu, R. G.; Celnik, P.; Claaßen, J.; Feil, K.; Kalla, R.; Miyai, I.; Nachbauer, W.; Schöls, L.; Strupp, M.; Synofzik, M.; Teufel, J.

    2015-01-01

    Treatment of motor symptoms of degenerative cerebellar ataxia remains difficult. Yet there are recent developments that are likely to lead to significant improvements in the future. Most desirable would be a causative treatment of the underlying cerebellar disease. This is currently available only for a very small subset of cerebellar ataxias with known metabolic dysfunction. However, increasing knowledge of the pathophysiology of hereditary ataxia should lead to an increasing number of medically sensible drug trials. In this paper, data from recent drug trials in patients with recessive and dominant cerebellar ataxias will be summarized. There is consensus that up to date, no medication has been proven effective. Aminopyridines and acetazolamide are the only exception, which are beneficial in patients with episodic ataxia type 2. Aminopyridines are also effective in a subset of patients presenting with downbeat nystagmus. As such, all authors agreed that the mainstays of treatment of degenerative cerebellar ataxia are currently physiotherapy, occupational therapy, and speech therapy. For many years, well-controlled rehabilitation studies in patients with cerebellar ataxia were lacking. Data of recently published studies show that coordinative training improves motor function in both adult and juvenile patients with cerebellar degeneration. Given the well-known contribution of the cerebellum to motor learning, possible mechanisms underlying improvement will be outlined. There is consensus that evidence-based guidelines for the physiotherapy of degenerative cerebellar ataxia need to be developed. Future developments in physiotherapeutical interventions will be discussed including application of non-invasive brain stimulation. PMID:24222635

  1. Consensus statement on panic disorder from the International Consensus Group on Depression and Anxiety

    NARCIS (Netherlands)

    Ballenger, JC; Lecrubier, Y; Nutt, DJ; Baldwin, DS; den Boer, JA; Kasper, S; Shear, MK

    1998-01-01

    Objective: To provide primary care clinicians with a better understanding of management issues in panic disorder and guide clinical practice with recommendations for appropriate pharmacotherapy. Participants: The 4 members of the International Consensus Group on Depression and Anxiety were James C.

  2. Seeking consensus for cyberinfrastructure governance in the USA

    Science.gov (United States)

    Allison, M. Lee; Zanzkerkia, Eva

    2014-05-01

    Governance of geosciences cyberinfrastructure is a complex and essential undertaking, critical in enabling distributed knowledge communities to collaborate and communicate across disciplines, distances, and cultures. Advancing science with respect to "grand challenges," such as global change, Earth system observation, modeling, and prediction, and core fundamental science, depends not just on technical cyber systems, but also on social systems for strategic planning, decision-making, project management, learning, teaching, and building a community of practice. Simply put, a robust, agile technical system depends on an equally robust and adaptable social system. Cyberinfrastructure development is wrapped in social, organizational and governance challenges which may significantly impede technical progress and result in inefficiencies, duplication of effort, incompatibilities, wasted resources or user frustration. These issues are also the most time consuming to resolve due to significant institutional and social inertia: hence the urgency for developing a governance blueprint. An agile development process is underway for governance of transformative investments in geosciences cyberinfrastructure through the US National Science Foundation's EarthCube Program. Agile development is iterative and incremental, and promotes adaptive planning and rapid and flexible response. Such iterative deployment across a variety of EarthCube stakeholders encourages transparency, consensus, accountability, and inclusiveness. A broad coalition of stakeholder groups comprises an Assembly to serve as a preliminary venue for identifying, evaluating, and testing potential governance models. To offer opportunity for ensure broader end-user input and buy-in, a crowd-source approach engages stakeholders not involved otherwise in the Assembly. Developmental evaluators from the social sciences embedded in the project will provide real-time review and adjustments. In order to ensure an open and

  3. Consensus based on learning game theory with a UAV rendezvous application

    Directory of Open Access Journals (Sweden)

    Lin Zhongjie

    2015-02-01

    Full Text Available Multi-agent cooperation problems are becoming more and more attractive in both civilian and military applications. In multi-agent cooperation problems, different network topologies will decide different manners of cooperation between agents. A centralized system will directly control the operation of each agent with information flow from a single centre, while in a distributed system, agents operate separately under certain communication protocols. In this paper, a systematic distributed optimization approach will be established based on a learning game algorithm. The convergence of the algorithm will be proven under the game theory framework. Two typical consensus problems will be analyzed with the proposed algorithm. The contributions of this work are threefold. First, the designed algorithm inherits the properties in learning game theory for problem simplification and proof of convergence. Second, the behaviour of learning endows the algorithm with robustness and autonomy. Third, with the proposed algorithm, the consensus problems will be analyzed from a novel perspective.

  4. Neuro-Adaptive Consensus Tracking of Multiagent Systems With a High-Dimensional Leader.

    Science.gov (United States)

    Wen, Guanghui; Yu, Wenwu; Li, Zhongkui; Yu, Xinghuo; Cao, Jinde

    2016-05-05

    \\looseness1This paper is concerned with the distributed consensus tracking problem of uncertain multiagent systems with directed communication topology and a single high-dimensional leader. Compared with existing related works, the dynamics of each follower in the present framework are subject to unmodeled dynamics and unknown external disturbances, which is more practical in various applications. Furthermore, the dimensions of leader's dynamics may be different with those of the followers' dynamics. Under the mild assumption that each follower can directly or indirectly sense the output information of the leader, a distributed robust adaptive neural network controller together with a local observer are designed to each follower to ensure that the states of each follower ultimately synchronize to the leader's output with bounded residual errors under a fixed topology. By appropriately constructing some multiple Lyapunov functions, the derived results are further extended to consensus tracking with switching directed communication topologies. The effectiveness of the analytical results is demonstrated via numerical simulations.

  5. Consensus based on learning game theory with a UAV rendezvous application

    Institute of Scientific and Technical Information of China (English)

    Lin Zhongjie; Liu Hugh hong-tao

    2015-01-01

    Multi-agent cooperation problems are becoming more and more attractive in both civil-ian and military applications. In multi-agent cooperation problems, different network topologies will decide different manners of cooperation between agents. A centralized system will directly control the operation of each agent with information flow from a single centre, while in a distrib-uted system, agents operate separately under certain communication protocols. In this paper, a sys-tematic distributed optimization approach will be established based on a learning game algorithm. The convergence of the algorithm will be proven under the game theory framework. Two typical consensus problems will be analyzed with the proposed algorithm. The contributions of this work are threefold. First, the designed algorithm inherits the properties in learning game theory for problem simplification and proof of convergence. Second, the behaviour of learning endows the algorithm with robustness and autonomy. Third, with the proposed algorithm, the consensus problems will be analyzed from a novel perspective.

  6. Bounds on Average Time Complexity of Decision Trees

    KAUST Repository

    Chikalov, Igor

    2011-01-01

    In this chapter, bounds on the average depth and the average weighted depth of decision trees are considered. Similar problems are studied in search theory [1], coding theory [77], design and analysis of algorithms (e.g., sorting) [38]. For any diagnostic problem, the minimum average depth of decision tree is bounded from below by the entropy of probability distribution (with a multiplier 1/log2 k for a problem over a k-valued information system). Among diagnostic problems, the problems with a complete set of attributes have the lowest minimum average depth of decision trees (e.g, the problem of building optimal prefix code [1] and a blood test study in assumption that exactly one patient is ill [23]). For such problems, the minimum average depth of decision tree exceeds the lower bound by at most one. The minimum average depth reaches the maximum on the problems in which each attribute is "indispensable" [44] (e.g., a diagnostic problem with n attributes and kn pairwise different rows in the decision table and the problem of implementing the modulo 2 summation function). These problems have the minimum average depth of decision tree equal to the number of attributes in the problem description. © Springer-Verlag Berlin Heidelberg 2011.

  7. In vitro and in vivo replication of a chemically synthesized consensus genome of hepatitis B virus genotype B.

    Science.gov (United States)

    Zhang, Zhenhua; Xia, Jianbo; Sun, Binghu; Dai, Yu; Li, Xu; Schlaak, Joerg F; Lu, Mengji

    2015-03-01

    Hepatitis B virus (HBV) genotypes vary in their geographical distribution and virological features. Previous investigations have shown that HBV genotype B is a predominant HBV genotype in China. Studies on HBV concerning different isolates frequently meet the question about the HBV reference strain and its representativeness. Although HBV consensus sequences can be generated easily by sequence alignment, they may not exist in nature or could not usually be isolated from patient samples. Thus, the construction of a consensus HBV genome has been proposed. In this study, an HBV genotype B consensus sequence was established by comparing 42 full-length HBV genotype B sequences and the genome was generated by chemical synthesis. This consensus genome was fully replication competent by in vitro transfection into hepatoma cells. The plasmid pHBV1.3B carrying a 1.3× full-length HBV consensus genome was hydrodynamically injected into Balb/c mice. HBsAg, anti-HBs, HBeAg, anti-HBe, and anti-HBc detection indicated expression and replication of this HBV genome in mice, similar to other HBV isolates. This approach represents a strategy to design and create consensus HBV genomes for future studies.

  8. Consensus on Moving Neighborhood Model of Peterson Graph

    CERN Document Server

    Arendt, Hannah

    2012-01-01

    In this paper, we study the consensus problem of multiple agents on a kind of famous graph, Peterson graph. It is an undirected graph with 10 vertices and 15 edges. Each agent randomly walks on this graph and communicates with each other if and only if they coincide on a node at the same time. We conduct numerical study on the consensus problem in this framework and show that global consensus can be achieved.

  9. Consensus of Heterogeneous Multiagent Systems with Arbitrarily Bounded Communication Delay

    Directory of Open Access Journals (Sweden)

    Xue Li

    2017-01-01

    Full Text Available This paper focuses on the consensus problem of high-order heterogeneous multiagent systems with arbitrarily bounded communication delays. Through the method of nonnegative matrices, we get a sufficient consensus condition for the systems with dynamically changing topology. The results of this paper show, even when there are arbitrarily bounded communication delays in the systems, all agents can reach a consensus no matter whether there are spanning trees for the corresponding communication graphs at any time.

  10. WIDTHS AND AVERAGE WIDTHS OF SOBOLEV CLASSES

    Institute of Scientific and Technical Information of China (English)

    刘永平; 许贵桥

    2003-01-01

    This paper concerns the problem of the Kolmogorov n-width, the linear n-width, the Gel'fand n-width and the Bernstein n-width of Sobolev classes of the periodicmultivariate functions in the space Lp(Td) and the average Bernstein σ-width, averageKolmogorov σ-widths, the average linear σ-widths of Sobolev classes of the multivariatequantities.

  11. Minimum-Time Consensus-Based Approach for Power System Applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tao; Wu, Di; Sun, Yannan; Lian, Jianming

    2016-02-01

    This paper presents minimum-time consensus based distributed algorithms for power system applications, such as load shedding and economic dispatch. The proposed algorithms are capable of solving these problems in a minimum number of time steps instead of asymptotically as in most of existing studies. Moreover, these algorithms are applicable to both undirected and directed communication networks. Simulation results are used to validate the proposed algorithms.

  12. Stochastic averaging of quasi-Hamiltonian systems

    Institute of Scientific and Technical Information of China (English)

    朱位秋

    1996-01-01

    A stochastic averaging method is proposed for quasi-Hamiltonian systems (Hamiltonian systems with light dampings subject to weakly stochastic excitations). Various versions of the method, depending on whether the associated Hamiltonian systems are integrable or nonintegrable, resonant or nonresonant, are discussed. It is pointed out that the standard stochastic averaging method and the stochastic averaging method of energy envelope are special cases of the stochastic averaging method of quasi-Hamiltonian systems and that the results obtained by this method for several examples prove its effectiveness.

  13. NOAA Average Annual Salinity (3-Zone)

    Data.gov (United States)

    California Department of Resources — The 3-Zone Average Annual Salinity Digital Geography is a digital spatial framework developed using geographic information system (GIS) technology. These salinity...

  14. Composite Backstepping Consensus Algorithms of Leader-Follower Higher-Order Nonlinear Multiagent Systems Subject to Mismatched Disturbances.

    Science.gov (United States)

    Wang, Xiangyu; Li, Shihua; Chen, Michael Z Q

    2017-07-27

    This paper is devoted to solving the output consensus problem of leader-follower higher-order nonlinear multiagent systems subject to mismatched disturbances. The disturbances are allowed to be in higher-order forms. First, by constructing a generalized proportional-integral observer for each follower, estimates of the disturbances and their derivatives are obtained. At the same time, a distributed observer is also developed for the followers to estimate the leader state information. Second, based on the estimates of the disturbances and the leader state, together with the backstepping technique, a feedforward-feedback composite consensus control scheme is proposed. The designed distributed protocols guarantee asymptotic output consensus for the agents. Simulation results validate the effectiveness of the proposed composite control scheme.

  15. Serving by local consensus in the public service location game

    Science.gov (United States)

    Sun, Yi-Fan; Zhou, Hai-Jun

    2016-09-01

    We discuss the issue of distributed and cooperative decision-making in a network game of public service location. Each node of the network can decide to host a certain public service incurring in a construction cost and serving all the neighboring nodes and itself. A pure consumer node has to pay a tax, and the collected tax is evenly distributed to all the hosting nodes to remedy their construction costs. If all nodes make individual best-response decisions, the system gets trapped in an inefficient situation of high tax level. Here we introduce a decentralized local-consensus selection mechanism which requires nodes to recommend their neighbors of highest local impact as candidate servers, and a node may become a server only if all its non-server neighbors give their assent. We demonstrate that although this mechanism involves only information exchange among neighboring nodes, it leads to socially efficient solutions with tax level approaching the lowest possible value. Our results may help in understanding and improving collective problem-solving in various networked social and robotic systems.

  16. Consensus formation in science modeled by aggregated bibliographic coupling

    DEFF Research Database (Denmark)

    Nicolaisen, Jeppe; Frandsen, Tove Faber

    2012-01-01

    The level of consensus in science has traditionally been measured by a number of different methods. The variety is important as each method measures different aspects of science and consensus. Citation analytical studies have previously measured the level of consensus using the scientific journal...... as their unit of analysis. To produce a more fine grained citation analysis one needs to study consensusformation on an even more detailed level – i.e. the scientific document or article. To do so, we have developed a new technique that measures consensus by aggregatedbibliographiccouplings (ABC) between...

  17. Consensus and Stability Analysis of Networked Multiagent Predictive Control Systems.

    Science.gov (United States)

    Liu, Guo-Ping

    2017-04-01

    This paper is concerned with the consensus and stability problem of multiagent control systems via networks with communication delays and data loss. A networked multiagent predictive control scheme is proposed to achieve output consensus and also compensate for the communication delays and data loss actively. The necessary and sufficient conditions of achieving both consensus and stability of the closed-loop networked multiagent control systems are derived. An important result that is obtained is that the consensus and stability of closed-loop networked multiagent predictive control systems are not related to the communication delays and data loss. An example illustrates the performance of the networked multiagent predictive control scheme.

  18. NASA's strategic direction and the need for a national consensus

    National Research Council Canada - National Science Library

    Division on Engineering and Physical Sciences; National Research Council; Committee on NASA's Strategic Direction

    2012-01-01

    ...? After a "comprehensive independent assessment of NASA's strategic direction and agency management", the NRC Committee determined that, only with a national consensus on the agency's future strategic...

  19. Consensus states of local majority rule in stochastic process

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Yu-Pin [Department of Electronic Engineering, National Formosa University, Huwei, 63201, Taiwan (China); Tang, Chia-Wei; Xu, Hong-Yuan [Department of Physics, Chung-Yuan Christian University, Chungli, 32023, Taiwan (China); Wu, Jinn-Wen [Department of Applied Mathematics, Chung-Yuan Christian University, Chungli, 32023, Taiwan (China); Huang, Ming-Chang, E-mail: mchuang@cycu.edu.tw [Center for Theoretical Science and Department of Physics, Chung-Yuan Christian University, Chungli, 32023, Taiwan (China)

    2015-04-03

    A sufficient condition for a network system to reach a consensus state of the local majority rule is shown. The influence of interpersonal environment on the occurrence probability of consensus states for Watts–Strogatz and scale-free networks with random initial states is analyzed by numerical method. We also propose a stochastic local majority rule to study the mean first passage time from a random state to a consensus and the escape rate from a consensus state for systems in a noisy environment. Our numerical results show that there exists a window of fluctuation strengths for which the mean first passage time from a random to a consensus state reduces greatly, and the escape rate of consensus states obeys the Arrhenius equation in the window. - Highlights: • A sufficient condition for reaching a consensus. • The relation between the geometry of networks and the reachability of a consensus. • Stochastic local majority rule. • The mean first-passage time and the escape rate of consensus states.

  20. Beyond consensus: statistical free energies reveal hidden interactions in the design of a TPR motif.

    Science.gov (United States)

    Magliery, Thomas J; Regan, Lynne

    2004-10-22

    Consensus design methods have been used successfully to engineer proteins with a particular fold, and moreover to engineer thermostable exemplars of particular folds. Here, we consider how a statistical free energy approach can expand upon current methods of phylogenetic design. As an example, we have analyzed the tetratricopeptide repeat (TPR) motif, using multiple sequence alignment to identify the significance of each position in the TPR. The results provide information above and beyond that revealed by consensus design alone, especially at poorly conserved positions. A particularly striking finding is that certain residues, which TPR-peptide co-crystal structures show are in direct contact with the ligand, display a marked hypervariability. This suggests a novel means of identifying ligand-binding sites, and also implies that TPRs generally function as ligand-binding domains. Using perturbation analysis (or statistical coupling analysis), we examined site-site interactions within the TPR motif. Correlated occurrences of amino acid residues at poorly conserved positions explain how TPRs achieve their near-neutral surface charge distributions, and why a TPR designed from straight consensus has an unusually high net charge. Networks of interacting sites revealed that TPRs fall into two unrecognized families with distinct sets of interactions related to the identity of position 7 (Leu or Lys/Arg). Statistical free energy analysis provides a more complete description of "What makes a TPR a TPR?" than consensus alone, and it suggests general approaches to extend and improve the phylogenetic design of proteins.

  1. Robust Adaptive Sliding Mode Consensus of Multiagent Systems with Perturbed Communications and Actuators

    Directory of Open Access Journals (Sweden)

    Xiao-Zheng Jin

    2013-01-01

    Full Text Available This paper deals with the asymptotic consensus problem for a class of multiagent systems with time-varying additive actuator faults and perturbed communications. The L2 performance of systems is also considered in the consensus controller designs. The upper and lower bounds of faults and perturbations in actuators and communications and controller gains are assumed to be unknown but can be estimated by designing some indirect adaptive laws. Based on the information from the adaptive estimation mechanism, the distributed robust adaptive sliding mode controllers are constructed to automatically compensate for the effects of faults and perturbations and to achieve any given level of L2 gain attenuation from external disturbance to consensus errors. Through Lyapunov functions and adaptive schemes, the asymptotic consensus of resulting adaptive multiagent system can be achieved with a specified performance criterion in the presence of perturbed communications and actuators. The effectiveness of the proposed design is illustrated via a decoupled longitudinal model of F-18 aircraft.

  2. Transversely isotropic higher-order averaged structure tensors

    Science.gov (United States)

    Hashlamoun, Kotaybah; Federico, Salvatore

    2017-08-01

    For composites or biological tissues reinforced by statistically oriented fibres, a probability distribution function is often used to describe the orientation of the fibres. The overall effect of the fibres on the material response is accounted for by evaluating averaging integrals over all possible directions in space. The directional average of the structure tensor (tensor product of the unit vector describing the fibre direction by itself) is of high significance. Higher-order averaged structure tensors feature in several models and carry similarly important information. However, their evaluation has a quite high computational cost. This work proposes to introduce mathematical techniques to minimise the computational cost associated with the evaluation of higher-order averaged structure tensors, for the case of a transversely isotropic probability distribution of orientation. A component expression is first introduced, using which a general tensor expression is obtained, in terms of an orthonormal basis in which one of the vectors coincides with the axis of symmetry of transverse isotropy. Then, a higher-order transversely isotropic averaged structure tensor is written in an appropriate basis, constructed starting from the basis of the space of second-order transversely isotropic tensors, which is constituted by the structure tensor and its complement to the identity.

  3. Dynamic Multiscale Averaging (DMA) of Turbulent Flow

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson

    2012-09-01

    A new approach called dynamic multiscale averaging (DMA) for computing the effects of turbulent flow is described. The new method encompasses multiple applications of temporal and spatial averaging, that is, multiscale operations. Initially, a direct numerical simulation (DNS) is performed for a relatively short time; it is envisioned that this short time should be long enough to capture several fluctuating time periods of the smallest scales. The flow field variables are subject to running time averaging during the DNS. After the relatively short time, the time-averaged variables are volume averaged onto a coarser grid. Both time and volume averaging of the describing equations generate correlations in the averaged equations. These correlations are computed from the flow field and added as source terms to the computation on the next coarser mesh. They represent coupling between the two adjacent scales. Since they are computed directly from first principles, there is no modeling involved. However, there is approximation involved in the coupling correlations as the flow field has been computed for only a relatively short time. After the time and spatial averaging operations are applied at a given stage, new computations are performed on the next coarser mesh using a larger time step. The process continues until the coarsest scale needed is reached. New correlations are created for each averaging procedure. The number of averaging operations needed is expected to be problem dependent. The new DMA approach is applied to a relatively low Reynolds number flow in a square duct segment. Time-averaged stream-wise velocity and vorticity contours from the DMA approach appear to be very similar to a full DNS for a similar flow reported in the literature. Expected symmetry for the final results is produced for the DMA method. The results obtained indicate that DMA holds significant potential in being able to accurately compute turbulent flow without modeling for practical

  4. Consensus control of flexible-joint robots

    Science.gov (United States)

    Avila-Becerril, Sofía; Espinosa-Pérez, Gerardo; Panteley, Elena; Ortega, Romeo

    2015-06-01

    Synchronisation of networks composed by fully actuated robot manipulators has received a lot of attention from the control theory community. Unfortunately, the case of under-actuated robots has not been deeply studied. The aim of this paper is to extend previous results reported by the authors addressing the particular (but of practical interest) case of networks composed by flexible-joint robots. The main feature of the contribution is to consider a change of coordinates, first introduced in Nuno, Ortega, Basanes and Hill, to solve the consensus problem assuming the existence of unknown delays in the communication channels. The extension is twofold, namely: the presentation of a control scheme that, in contrast to the one considered in Avila-Becerril and Espinosa-Perez, does not require knowledge of the initial conditions and the proof that the controller can also be implemented in Cartesian coordinates. The usefulness of the contribution is illustrated through numerical simulations.

  5. Consensus and new improvements of disability glare

    Directory of Open Access Journals (Sweden)

    Yu-Wei Zheng

    2014-12-01

    Full Text Available Patients with early cataract may have normal visual acuity(VAbut complain that they have problems in driving at night, like seeing things through a veil. This phenomenon is defined as disability glare which maybe caused by growing stray light. Patients with intraocular lens following cataract surgery may complain about glare, halos and shadows in visual field, which are also resulted from dysphotopia. Disability glare is the VA loss due to disturbing luminance in visual field. In other words, it's the retinal contrast sensitivity reduction because of the straylight. This article contains the consensus and new progress of disability glare. It provides solutions according to its effect factors and offers clues for further study.

  6. CONSENSUS STATEMENT ON THE MANAGEMENT OF URTICARIA

    Science.gov (United States)

    Godse, Kiran V; Zawar, Vijay; Krupashankar, DS; Girdhar, Mukesh; Kandhari, Sanjiv; Dhar, Sandipan; Ghosh, Sanjay; Rajagopalan, Murlidhar; Zuberbier, Torsten

    2011-01-01

    This consensus statement was developed by Special Interest Group – Urticaria (IADVL). Urticaria, a heterogeneous group of diseases, often cannot be recognized by its morphology. Due to non-specific and non-affordable diagnosis, management of urticaria, especially chronic urticaria, is very challenging. This guideline includes definition, causes, classification and management of urticaria. Urticaria has a profound impact on the quality of life and causes immense distress to patients, necessitating effective treatment. One approach to manage urticaria is identification and elimination of the underlying cause(s) and/or eliciting trigger(s), while the second one is treatment aimed at providing symptomatic relief. This guideline recommends use of second-generation non-sedating H1 antihistamines as the first-line treatment. The dose can be increased up to four times to meet the expected results. In case patients still do not respond, appropriate treatment options can be selected depending on the cost. PMID:22121259

  7. Consensus document on European brain research

    DEFF Research Database (Denmark)

    Di Luca, Monica; Baker, Mary; Corradetti, Renato

    2011-01-01

    Psychiatric and neurological diseases combined represent a considerable social and economic burden in Europe. A recent study conducted by the European Brain Council (EBC) quantified the 'cost and burden' of major brain diseases in Europe, amounting to €386bn per year. Considering that these costs...... the economic and social challenge posed by management of brain diseases in European countries. To setup a platform for discussion, EBC published in 2006 a Consensus Document on European Brain Research, describing needs and achievements of research in Europe and presenting proposals for future research programs....... Since 2006, European research in neuroscience has advanced tremendously. The present document represents an update elaborated to reflect changes in research priorities and advances in brain research that have taken place since 2006. The same approach and format have been used here as in the previous...

  8. Consensus recommendations for anaesthetic peripheral nerve block.

    Science.gov (United States)

    Santos Lasaosa, S; Cuadrado Pérez, M L; Guerrero Peral, A L; Huerta Villanueva, M; Porta-Etessam, J; Pozo-Rosich, P; Pareja, J A

    2017-06-01

    Anaesthetic block, alone or in combination with other treatments, represents a therapeutic resource for treating different types of headaches. However, there is significant heterogeneity in patterns of use among different professionals. This consensus document has been drafted after a thorough review and analysis of the existing literature and our own clinical experience. The aim of this document is to serve as guidelines for professionals applying anaesthetic blocks. Recommendations are based on the levels of evidence of published studies on migraine, trigeminal autonomic cephalalgias, cervicogenic headache, and pericranial neuralgias. We describe the main technical and formal considerations of the different procedures, the potential adverse reactions, and the recommended approach. Anaesthetic block in patients with headache should always be individualised and based on a thorough medical history, a complete neurological examination, and expert technical execution. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. The Mexican consensus on probiotics in gastroenterology.

    Science.gov (United States)

    Valdovinos, M A; Montijo, E; Abreu, A T; Heller, S; González-Garay, A; Bacarreza, D; Bielsa-Fernández, M; Bojórquez-Ramos, M C; Bosques-Padilla, F; Burguete-García, A I; Carmona-Sánchez, R; Consuelo-Sánchez, A; Coss-Adame, E; Chávez-Barrera, J A; de Ariño, M; Flores-Calderón, J; Gómez-Escudero, O; González-Huezo, M S; Icaza-Chávez, M E; Larrosa-Haro, A; Morales-Arámbula, M; Murata, C; Ramírez-Mayans, J A; Remes-Troche, J M; Rizo-Robles, T; Peláez-Luna, M; Toro-Monjaraz, E M; Torre, A; Urquidi-Rivera, M E; Vázquez, R; Yamamoto-Furusho, J K; Guarner, F

    Probiotics are frequently prescribed in clinical practice. Their efficacy in treating gastrointestinal disorders is supported by a significant number of clinical trials. However, the correct prescription of these agents is hampered due to a lack of knowledge of the scientific evidence and to the different presentations and microbial compositions of the probiotics that are currently available. To provide the clinician with a consensus review of probiotics and recommendations for their use in gastroenterology. Controlled clinical trials, meta-analyses, and systematic reviews published up to 2015 were selected, using the MESH terms: probiotics, gastrointestinal diseases, humans, adults, AND children. The Delphi method was employed. Eighteen gastroenterologists treating adult patients and 14 pediatric gastroenterologists formulated statements that were voted on until agreement>70% was reached. The level of evidence based on the GRADE system was evaluated for each statement. Eleven statements on the general concepts of probiotics and 27 statements on the use of probiotics in gastrointestinal diseases in both adults and children were formulated. The consensus group recommends the use of probiotics under the following clinical conditions: the prevention of diarrhea associated with antibiotics, the treatment of acute infectious diarrhea, the prevention of Clostridium difficile infection and necrotizing enterocolitis, the reduction of adverse events from Helicobacter pylori eradication therapy, relief from irritable bowel syndrome symptoms, the treatment of functional constipation in the adult, and the induction and maintenance of remission in patients with ulcerative colitis and pouchitis, and the treatment of covert and overt hepatic encephalopathy. Copyright © 2016 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

  10. 2003 Canadian Asthma Consensus Guidelines Executive Summary

    Directory of Open Access Journals (Sweden)

    Becker Allan

    2006-03-01

    Full Text Available Abstract Background Guidelines for the diagnosis and management of asthma have been published over the last 15 years; however, there has been little focus on issues relating to asthma in childhood. Since the last revision of the 1999 Canadian Asthma Consensus Report, important new studies, particularly in children, have highlighted the need to incorporate new information into the asthma guidelines. The objectives of this article are to review the literature on asthma published between January 2000 and June 2003 and to evaluate the influence of new evidence on the recommendations made in the 1999 Canadian Asthma Consensus Report and its 2001 update, with a major focus on pediatric issues. Methods The diagnosis of asthma in young children and prevention strategies, pharmacotherapy, inhalation devices, immunotherapy, and asthma education were selected for review by small expert resource groups. The reviews were discussed in June 2003 at a meeting under the auspices of the Canadian Network For Asthma Care and the Canadian Thoracic Society. Data published through December 2004 were subsequently reviewed by the individual expert resource groups. Results This report evaluates early-life prevention strategies and focuses on treatment of asthma in children, emphasizing the importance of early diagnosis and preventive therapy, the benefits of additional therapy, and the essential role of asthma education. Conclusion We generally support previous recommendations and focus on new issues, particularly those relevant to children and their families. This document is a guide for asthma management based on the best available published data and the opinion of health care professionals, including asthma experts and educators.

  11. Average Transmission Probability of a Random Stack

    Science.gov (United States)

    Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

    2010-01-01

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

  12. Average sampling theorems for shift invariant subspaces

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The sampling theorem is one of the most powerful results in signal analysis. In this paper, we study the average sampling on shift invariant subspaces, e.g. wavelet subspaces. We show that if a subspace satisfies certain conditions, then every function in the subspace is uniquely determined and can be reconstructed by its local averages near certain sampling points. Examples are given.

  13. Testing linearity against nonlinear moving average models

    NARCIS (Netherlands)

    de Gooijer, J.G.; Brännäs, K.; Teräsvirta, T.

    1998-01-01

    Lagrange multiplier (LM) test statistics are derived for testing a linear moving average model against an additive smooth transition moving average model. The latter model is introduced in the paper. The small sample performance of the proposed tests are evaluated in a Monte Carlo study and compared

  14. Averaging Einstein's equations : The linearized case

    NARCIS (Netherlands)

    Stoeger, William R.; Helmi, Amina; Torres, Diego F.

    2007-01-01

    We introduce a simple and straightforward averaging procedure, which is a generalization of one which is commonly used in electrodynamics, and show that it possesses all the characteristics we require for linearized averaging in general relativity and cosmology for weak-field and perturbed FLRW situ

  15. Averaging Einstein's equations : The linearized case

    NARCIS (Netherlands)

    Stoeger, William R.; Helmi, Amina; Torres, Diego F.

    We introduce a simple and straightforward averaging procedure, which is a generalization of one which is commonly used in electrodynamics, and show that it possesses all the characteristics we require for linearized averaging in general relativity and cosmology for weak-field and perturbed FLRW

  16. Average excitation potentials of air and aluminium

    NARCIS (Netherlands)

    Bogaardt, M.; Koudijs, B.

    1951-01-01

    By means of a graphical method the average excitation potential I may be derived from experimental data. Average values for Iair and IAl have been obtained. It is shown that in representing range/energy relations by means of Bethe's well known formula, I has to be taken as a continuously changing fu

  17. Average Transmission Probability of a Random Stack

    Science.gov (United States)

    Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

    2010-01-01

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

  18. Measurement of the average lifetime of b hadrons

    Science.gov (United States)

    Adriani, O.; Aguilar-Benitez, M.; Ahlen, S.; Alcaraz, J.; Aloisio, A.; Alverson, G.; Alviggi, M. G.; Ambrosi, G.; An, Q.; Anderhub, H.; Anderson, A. L.; Andreev, V. P.; Angelescu, T.; Antonov, L.; Antreasyan, D.; Arce, P.; Arefiev, A.; Atamanchuk, A.; Azemoon, T.; Aziz, T.; Baba, P. V. K. S.; Bagnaia, P.; Bakken, J. A.; Ball, R. C.; Banerjee, S.; Bao, J.; Barillère, R.; Barone, L.; Baschirotto, A.; Battiston, R.; Bay, A.; Becattini, F.; Bechtluft, J.; Becker, R.; Becker, U.; Behner, F.; Behrens, J.; Bencze, Gy. L.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biland, A.; Bilei, G. M.; Bizzarri, R.; Blaising, J. J.; Bobbink, G. J.; Bock, R.; Böhm, A.; Borgia, B.; Bosetti, M.; Bourilkov, D.; Bourquin, M.; Boutigny, D.; Bouwens, B.; Brambilla, E.; Branson, J. G.; Brock, I. C.; Brooks, M.; Bujak, A.; Burger, J. D.; Burger, W. J.; Busenitz, J.; Buytenhuijs, A.; Cai, X. D.; Capell, M.; Caria, M.; Carlino, G.; Cartacci, A. M.; Castello, R.; Cerrada, M.; Cesaroni, F.; Chang, Y. H.; Chaturvedi, U. K.; Chemarin, M.; Chen, A.; Chen, C.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chen, M.; Chen, W. Y.; Chiefari, G.; Chien, C. Y.; Choi, M. T.; Chung, S.; Civinini, C.; Clare, I.; Clare, R.; Coan, T. E.; Cohn, H. O.; Coignet, G.; Colino, N.; Contin, A.; Costantini, S.; Cotorobai, F.; Cui, X. T.; Cui, X. Y.; Dai, T. S.; D'Alessandro, R.; de Asmundis, R.; Degré, A.; Deiters, K.; Dénes, E.; Denes, P.; DeNotaristefani, F.; Dhina, M.; DiBitonto, D.; Diemoz, M.; Dimitrov, H. R.; Dionisi, C.; Ditmarr, M.; Djambazov, L.; Dova, M. T.; Drago, E.; Duchesneau, D.; Duinker, P.; Duran, I.; Easo, S.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Erné, F. C.; Extermann, P.; Fabbretti, R.; Fabre, M.; Falciano, S.; Fan, S. J.; Fackler, O.; Fay, J.; Felcini, M.; Ferguson, T.; Fernandez, D.; Fernandez, G.; Ferroni, F.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, P. H.; Forconi, G.; Fredj, L.; Freudenreich, K.; Friebel, W.; Fukushima, M.; Gailloud, M.; Galaktionov, Yu.; Gallo, E.; Ganguli, S. N.; Garcia-Abia, P.; Gele, D.; Gentile, S.; Gheordanescu, N.; Giagu, S.; Goldfarb, S.; Gong, Z. F.; Gonzalez, E.; Gougas, A.; Goujon, D.; Gratta, G.; Gruenewald, M.; Gu, C.; Guanziroli, M.; Guo, J. K.; Gupta, V. K.; Gurtu, A.; Gustafson, H. R.; Gutay, L. J.; Hangarter, K.; Hartmann, B.; Hasan, A.; Hauschildt, D.; He, C. F.; He, J. T.; Hebbeker, T.; Hebert, M.; Hervé, A.; Hilgers, K.; Hofer, H.; Hoorani, H.; Hu, G.; Hu, G. Q.; Ille, B.; Ilyas, M. M.; Innocente, V.; Janssen, H.; Jezequel, S.; Jin, B. N.; Jones, L. W.; Josa-Mutuberria, I.; Kasser, A.; Khan, R. A.; Kamyshkov, Yu.; Kapinos, P.; Kapustinsky, J. S.; Karyotakis, Y.; Kaur, M.; Khokhar, S.; Kienzle-Focacci, M. N.; Kim, J. K.; Kim, S. C.; Kim, Y. G.; Kinnison, W. W.; Kirkby, A.; Kirkby, D.; Kirsch, S.; Kittel, W.; Klimentov, A.; Klöckner, R.; König, A. C.; Koffeman, E.; Kornadt, O.; Koutsenko, V.; Koulbardis, A.; Kraemer, R. W.; Kramer, T.; Krastev, V. R.; Krenz, W.; Krivshich, A.; Kuijten, H.; Kumar, K. S.; Kunin, A.; Landi, G.; Lanske, D.; Lanzano, S.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Lee, D. M.; Lee, J. S.; Lee, K. Y.; Leedom, I.; Leggett, C.; Le Goff, J. M.; Leiste, R.; Lenti, M.; Leonardi, E.; Li, C.; Li, H. T.; Li, P. J.; Liao, J. Y.; Lin, W. T.; Lin, Z. Y.; Linde, F. L.; Lindemann, B.; Lista, L.; Liu, Y.; Lohmann, W.; Longo, E.; Lu, Y. S.; Lubbers, J. M.; Lübelsmeyer, K.; Luci, C.; Luckey, D.; Ludovici, L.; Luminari, L.; Lustermann, W.; Ma, J. M.; Ma, W. G.; MacDermott, M.; Malik, R.; Malinin, A.; Maña, C.; Maolinbay, M.; Marchesini, P.; Marion, F.; Marin, A.; Martin, J. P.; Martinez-Laso, L.; Marzano, F.; Massaro, G. G. G.; Mazumdar, K.; McBride, P.; McMahon, T.; McNally, D.; Merk, M.; Merola, L.; Meschini, M.; Metzger, W. J.; Mi, Y.; Mihul, A.; Mills, G. B.; Mir, Y.; Mirabelli, G.; Mnich, J.; Möller, M.; Monteleoni, B.; Morand, R.; Morganti, S.; Moulai, N. E.; Mount, R.; Müller, S.; Nadtochy, A.; Nagy, E.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Neyer, C.; Niaz, M. A.; Nippe, A.; Nowak, H.; Organtini, G.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Pascale, G.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pei, Y. J.; Pensotti, S.; Perret-Gallix, D.; Perrier, J.; Pevsner, A.; Piccolo, D.; Pieri, M.; Piroué, P. A.; Plasil, F.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Qi, Z. D.; Qian, J. M.; Qureshi, K. N.; Raghavan, R.; Rahal-Callot, G.; Rancoita, P. G.; Rattaggi, M.; Raven, G.; Razis, P.; Read, K.; Ren, D.; Ren, Z.; Rescigno, M.; Reucroft, S.; Ricker, A.; Riemann, S.; Riemers, B. C.; Riles, K.; Rind, O.; Rizvi, H. A.; Ro, S.; Rodriguez, F. J.; Roe, B. P.; Röhner, M.; Romero, L.; Rosier-Lees, S.; Rosmalen, R.; Rosselet, Ph.; van Rossum, W.; Roth, S.; Rubbia, A.; Rubio, J. A.; Rykaczewski, H.; Sachwitz, M.; Salicio, J.; Salicio, J. M.; Sanders, G. S.; Santocchia, A.; Sarakinos, M. S.; Sartorelli, G.; Sassowsky, M.; Sauvage, G.; Schegelsky, V.; Schmitz, D.; Schmitz, P.; Schneegans, M.; Schopper, H.; Schotanus, D. J.; Shotkin, S.; Schreiber, H. J.; Shukla, J.; Schulte, R.; Schulte, S.; Schultze, K.; Schwenke, J.; Schwering, G.; Sciacca, C.; Scott, I.; Sehgal, R.; Seiler, P. G.; Sens, J. C.; Servoli, L.; Sheer, I.; Shen, D. Z.; Shevchenko, S.; Shi, X. R.; Shumilov, E.; Shoutko, V.; Son, D.; Sopczak, A.; Soulimov, V.; Spartiotis, C.; Spickermann, T.; Spillantini, P.; Starosta, R.; Steuer, M.; Stickland, D. P.; Sticozzi, F.; Stone, H.; Strauch, K.; Stringfellow, B. C.; Sudhakar, K.; Sultanov, G.; Sun, L. Z.; Susinno, G. F.; Suter, H.; Swain, J. D.; Syed, A. A.; Tang, X. W.; Taylor, L.; Terzi, G.; Ting, Samuel C. C.; Ting, S. M.; Tonutti, M.; Tonwar, S. C.; Tóth, J.; Tsaregorodtsev, A.; Tsipolitis, G.; Tully, C.; Tung, K. L.; Ulbricht, J.; Urbán, L.; Uwer, U.; Valente, E.; Van de Walle, R. T.; Vetlitsky, I.; Viertel, G.; Vikas, P.; Vikas, U.; Vivargent, M.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A. A.; Vuilleumier, L.; Wadhwa, M.; Wallraff, W.; Wang, C.; Wang, C. R.; Wang, X. L.; Wang, Y. F.; Wang, Z. M.; Warner, C.; Weber, A.; Weber, J.; Weill, R.; Wenaus, T. J.; Wenninger, J.; White, M.; Willmott, C.; Wittgenstein, F.; Wright, D.; Wu, S. X.; Wynhoff, S.; Wysłouch, B.; Xie, Y. Y.; Xu, J. G.; Xu, Z. Z.; Xue, Z. L.; Yan, D. S.; Yang, B. Z.; Yang, C. G.; Yang, G.; Ye, C. H.; Ye, J. B.; Ye, Q.; Yeh, S. C.; Yin, Z. W.; You, J. M.; Yunus, N.; Yzerman, M.; Zaccardelli, C.; Zaitsev, N.; Zemp, P.; Zeng, M.; Zeng, Y.; Zhang, D. H.; Zhang, Z. P.; Zhou, B.; Zhou, G. J.; Zhou, J. F.; Zhu, R. Y.; Zichichi, A.; van der Zwaan, B. C. C.; L3 Collaboration

    1993-11-01

    The average lifetime of b hadrons has been measured using the L3 detector at LEP, running at √ s ≈ MZ. A b-enriched sample was obtained from 432538 hadronic Z events collected in 1990 and 1991 by tagging electrons and muons from semileptonic b hadron decays. From maximum likelihood fits to the electron and muon impact parameter distributions, the average b hadron lifetime was measured to be τb = (1535 ± 35 ± 28) fs, where the first error is statistical and the second includes both the experimental and the theoretical systematic uncertainties.

  19. Light shift averaging in paraffin-coated alkali vapor cells

    CERN Document Server

    Zhivun, Elena; Sudyka, Julia; Pustelny, Szymon; Patton, Brian; Budker, Dmitry

    2015-01-01

    Light shifts are an important source of noise and systematics in optically pumped magnetometers. We demonstrate that the long spin coherence time in paraffin-coated cells leads to spatial averaging of the light shifts over the entire cell volume. This renders the averaged light shift independent, under certain approximations, of the light-intensity distribution within the sensor cell. These results and the underlying mechanism can be extended to other spatially varying phenomena in anti-relaxation-coated cells with long coherence times.

  20. New results on averaging theory and applications

    Science.gov (United States)

    Cândido, Murilo R.; Llibre, Jaume

    2016-08-01

    The usual averaging theory reduces the computation of some periodic solutions of a system of ordinary differential equations, to find the simple zeros of an associated averaged function. When one of these zeros is not simple, i.e., the Jacobian of the averaged function in it is zero, the classical averaging theory does not provide information about the periodic solution associated to a non-simple zero. Here we provide sufficient conditions in order that the averaging theory can be applied also to non-simple zeros for studying their associated periodic solutions. Additionally, we do two applications of this new result for studying the zero-Hopf bifurcation in the Lorenz system and in the Fitzhugh-Nagumo system.

  1. Analogue Divider by Averaging a Triangular Wave

    Science.gov (United States)

    Selvam, Krishnagiri Chinnathambi

    2017-08-01

    A new analogue divider circuit by averaging a triangular wave using operational amplifiers is explained in this paper. The triangle wave averaging analog divider using operational amplifiers is explained here. The reference triangular waveform is shifted from zero voltage level up towards positive power supply voltage level. Its positive portion is obtained by a positive rectifier and its average value is obtained by a low pass filter. The same triangular waveform is shifted from zero voltage level to down towards negative power supply voltage level. Its negative portion is obtained by a negative rectifier and its average value is obtained by another low pass filter. Both the averaged voltages are combined in a summing amplifier and the summed voltage is given to an op-amp as negative input. This op-amp is configured to work in a negative closed environment. The op-amp output is the divider output.

  2. Methodological Quality of Consensus Guidelines in Implant Dentistry

    Science.gov (United States)

    Faggion, Clovis Mariano; Apaza, Karol; Ariza-Fritas, Tania; Málaga, Lilian; Giannakopoulos, Nikolaos Nikitas; Alarcón, Marco Antonio

    2017-01-01

    Background Consensus guidelines are useful to improve clinical decision making. Therefore, the methodological evaluation of these guidelines is of paramount importance. Low quality information may guide to inadequate or harmful clinical decisions. Objective To evaluate the methodological quality of consensus guidelines published in implant dentistry using a validated methodological instrument. Methods The six implant dentistry journals with impact factors were scrutinised for consensus guidelines related to implant dentistry. Two assessors independently selected consensus guidelines, and four assessors independently evaluated their methodological quality using the Appraisal of Guidelines for Research & Evaluation (AGREE) II instrument. Disagreements in the selection and evaluation of guidelines were resolved by consensus. First, the consensus guidelines were analysed alone. Then, systematic reviews conducted to support the guidelines were included in the analysis. Non-parametric statistics for dependent variables (Wilcoxon signed rank test) was used to compare both groups. Results Of 258 initially retrieved articles, 27 consensus guidelines were selected. Median scores in four domains (applicability, rigour of development, stakeholder involvement, and editorial independence), expressed as percentages of maximum possible domain scores, were below 50% (median, 26%, 30.70%, 41.70%, and 41.70%, respectively). The consensus guidelines and consensus guidelines + systematic reviews data sets could be compared for 19 guidelines, and the results showed significant improvements in all domain scores (p < 0.05). Conclusions Methodological improvement of consensus guidelines published in major implant dentistry journals is needed. The findings of the present study may help researchers to better develop consensus guidelines in implant dentistry, which will improve the quality and trust of information needed to make proper clinical decisions. PMID:28107405

  3. Observer-Based Event-Triggering Consensus Control for Multiagent Systems With Lossy Sensors and Cyber-Attacks.

    Science.gov (United States)

    Ding, Derui; Wang, Zidong; Ho, Daniel W C; Wei, Guoliang

    2016-07-07

    In this paper, the observer-based event-triggering consensus control problem is investigated for a class of discrete-time multiagent systems with lossy sensors and cyber-attacks. A novel distributed observer is proposed to estimate the relative full states and the estimated states are then used in the feedback protocol in order to achieve the overall consensus. An event-triggered mechanism with state-independent threshold is adopted to update the control input signals so as to reduce unnecessary data communications. The success ratio of the launched attacks is taken into account to reflect the probabilistic failures of the attacks passing through the protection devices subject to limited resources and network fluctuations. The purpose of the address problem is to design an observer-based distributed controller such that the closed-loop multiagent system achieves the prescribed consensus in spite of the lossy sensors and cyber-attacks. By making use of eigenvalues and eigenvectors of the Laplacian matrix, the closed-loop system is transformed into an easy-to-analyze setting and then a sufficient condition is derived to guarantee the desired consensus. Furthermore, the controller gain is obtained in terms of the solution to certain matrix inequality which is independent of the number of agents. An algorithm is provided to optimize the consensus bound. Finally, a simulation example is utilized to illustrate the usefulness of the proposed controller design scheme.

  4. Gossip Consensus Algorithm Based on Time-Varying Influence Factors and Weakly Connected Graph for Opinion Evolution in Social Networks

    Directory of Open Access Journals (Sweden)

    Lingyun Li

    2013-01-01

    Full Text Available We provide a new gossip algorithm to investigate the problem of opinion consensus with the time-varying influence factors and weakly connected graph among multiple agents. What is more, we discuss not only the effect of the time-varying factors and the randomized topological structure but also the spread of misinformation and communication constrains described by probabilistic quantized communication in the social network. Under the underlying weakly connected graph, we first denote that all opinion states converge to a stochastic consensus almost surely; that is, our algorithm indeed achieves the consensus with probability one. Furthermore, our results show that the mean of all the opinion states converges to the average of the initial states when time-varying influence factors satisfy some conditions. Finally, we give a result about the square mean error between the dynamic opinion states and the benchmark without quantized communication.

  5. Consensus seeking in multi-agent systems with noisy and delayed communication in digraphs having spanning tree

    Science.gov (United States)

    Djaidja, Sabir; Wu, Qinghe

    2016-09-01

    This paper studies the consensus problem of continuous-time single-integrator multi-agent systems with measurement noises and time delays under directed fixed topologies. Each agent in the team receives imprecise and delayed information from its neighbours. The noises are considered white noises, and time delays are assumed to be uniform for all the received information states. An analysis framework based on graph theory and stochastic tools is followed to derive conditions under which the asymptotic unbiased mean square linear χ-consensus is achieved in directed fixed topologies having a spanning tree. Then, conditions to achieve asymptotic unbiased mean square average consensus are deduced for fixed balanced digraphs having a spanning tree. The effectiveness of the proposed algorithms is proved through some simulations.

  6. Averaged Lema\\^itre-Tolman-Bondi dynamics

    CERN Document Server

    Isidro, Eddy G Chirinos; Piattella, Oliver F; Zimdahl, Winfried

    2016-01-01

    We consider cosmological backreaction effects in Buchert's averaging formalism on the basis of an explicit solution of the Lema\\^itre-Tolman-Bondi (LTB) dynamics which is linear in the LTB curvature parameter and has an inhomogeneous bang time. The volume Hubble rate is found in terms of the volume scale factor which represents a derivation of the simplest phenomenological solution of Buchert's equations in which the fractional densities corresponding to average curvature and kinematic backreaction are explicitly determined by the parameters of the underlying LTB solution at the boundary of the averaging volume. This configuration represents an exactly solvable toy model but it does not adequately describe our "real" Universe.

  7. Average-passage flow model development

    Science.gov (United States)

    Adamczyk, John J.; Celestina, Mark L.; Beach, Tim A.; Kirtley, Kevin; Barnett, Mark

    1989-01-01

    A 3-D model was developed for simulating multistage turbomachinery flows using supercomputers. This average passage flow model described the time averaged flow field within a typical passage of a bladed wheel within a multistage configuration. To date, a number of inviscid simulations were executed to assess the resolution capabilities of the model. Recently, the viscous terms associated with the average passage model were incorporated into the inviscid computer code along with an algebraic turbulence model. A simulation of a stage-and-one-half, low speed turbine was executed. The results of this simulation, including a comparison with experimental data, is discussed.

  8. FREQUENTIST MODEL AVERAGING ESTIMATION: A REVIEW

    Institute of Scientific and Technical Information of China (English)

    Haiying WANG; Xinyu ZHANG; Guohua ZOU

    2009-01-01

    In applications, the traditional estimation procedure generally begins with model selection.Once a specific model is selected, subsequent estimation is conducted under the selected model without consideration of the uncertainty from the selection process. This often leads to the underreporting of variability and too optimistic confidence sets. Model averaging estimation is an alternative to this procedure, which incorporates model uncertainty into the estimation process. In recent years, there has been a rising interest in model averaging from the frequentist perspective, and some important progresses have been made. In this paper, the theory and methods on frequentist model averaging estimation are surveyed. Some future research topics are also discussed.

  9. Averaging of Backscatter Intensities in Compounds

    Science.gov (United States)

    Donovan, John J.; Pingitore, Nicholas E.; Westphal, Andrew J.

    2002-01-01

    Low uncertainty measurements on pure element stable isotope pairs demonstrate that mass has no influence on the backscattering of electrons at typical electron microprobe energies. The traditional prediction of average backscatter intensities in compounds using elemental mass fractions is improperly grounded in mass and thus has no physical basis. We propose an alternative model to mass fraction averaging, based of the number of electrons or protons, termed “electron fraction,” which predicts backscatter yield better than mass fraction averaging. PMID:27446752

  10. Experimental Demonstration of Squeezed State Quantum Averaging

    CERN Document Server

    Lassen, Mikael; Sabuncu, Metin; Filip, Radim; Andersen, Ulrik L

    2010-01-01

    We propose and experimentally demonstrate a universal quantum averaging process implementing the harmonic mean of quadrature variances. The harmonic mean protocol can be used to efficiently stabilize a set of fragile squeezed light sources with statistically fluctuating noise levels. The averaged variances are prepared probabilistically by means of linear optical interference and measurement induced conditioning. We verify that the implemented harmonic mean outperforms the standard arithmetic mean strategy. The effect of quantum averaging is experimentally tested both for uncorrelated and partially correlated noise sources with sub-Poissonian shot noise or super-Poissonian shot noise characteristics.

  11. The Average Lower Connectivity of Graphs

    Directory of Open Access Journals (Sweden)

    Ersin Aslan

    2014-01-01

    Full Text Available For a vertex v of a graph G, the lower connectivity, denoted by sv(G, is the smallest number of vertices that contains v and those vertices whose deletion from G produces a disconnected or a trivial graph. The average lower connectivity denoted by κav(G is the value (∑v∈VGsvG/VG. It is shown that this parameter can be used to measure the vulnerability of networks. This paper contains results on bounds for the average lower connectivity and obtains the average lower connectivity of some graphs.

  12. Cosmic inhomogeneities and averaged cosmological dynamics.

    Science.gov (United States)

    Paranjape, Aseem; Singh, T P

    2008-10-31

    If general relativity (GR) describes the expansion of the Universe, the observed cosmic acceleration implies the existence of a "dark energy." However, while the Universe is on average homogeneous on large scales, it is inhomogeneous on smaller scales. While GR governs the dynamics of the inhomogeneous Universe, the averaged homogeneous Universe obeys modified Einstein equations. Can such modifications alone explain the acceleration? For a simple generic model with realistic initial conditions, we show the answer to be "no." Averaging effects negligibly influence the cosmological dynamics.

  13. Changing mortality and average cohort life expectancy

    DEFF Research Database (Denmark)

    Schoen, Robert; Canudas-Romo, Vladimir

    2005-01-01

    of survivorship. An alternative aggregate measure of period mortality which has been seen as less sensitive to period changes, the cross-sectional average length of life (CAL) has been proposed as an alternative, but has received only limited empirical or analytical examination. Here, we introduce a new measure......, the average cohort life expectancy (ACLE), to provide a precise measure of the average length of life of cohorts alive at a given time. To compare the performance of ACLE with CAL and with period and cohort life expectancy, we first use population models with changing mortality. Then the four aggregate...

  14. Consensus in Directed Networks of Agents With Nonlinear Dynamics

    NARCIS (Netherlands)

    Yu, Wenwu; Chen, Guanrong; Cao, Ming; Qu, Z.

    2011-01-01

    This technical note studies the consensus problem for cooperative agents with nonlinear dynamics in a directed network. Both local and global consensus are defined and investigated. Techniques for studying the synchronization in such complex networks are exploited to establish various sufficient con

  15. 77 FR 24251 - Consensus Standards, Light-Sport Aircraft

    Science.gov (United States)

    2012-04-23

    ... Federal Aviation Administration Consensus Standards, Light-Sport Aircraft AGENCY: Federal Aviation... availability of three new and three revised consensus standards relating to the provisions of the Sport Pilot and Light-Sport Aircraft rule issued July 16, 2004, and effective September 1, 2004....

  16. 78 FR 35085 - Consensus Standards, Light-Sport Aircraft

    Science.gov (United States)

    2013-06-11

    ... Federal Aviation Administration Consensus Standards, Light-Sport Aircraft AGENCY: Federal Aviation... availability of one new and seven revised consensus standards relating to the provisions of the Sport Pilot and Light-Sport Aircraft rule issued July 16, 2004, and effective September 1, 2004. ASTM...

  17. Kyoto global consensus report on Helicobacter pylori gastritis

    NARCIS (Netherlands)

    K. Sugano (Kentaro); J. Tack (Jan); E.J. Kuipers (Ernst); D.Y. Graham (David Y.); E. El-Omar; S. Miura (Soichiro); K. Haruma (Ken); M. Asaka (Masahiro); N. Uemura (Naomi); P. Malfertheiner

    2015-01-01

    textabstractObjective To present results of the Kyoto Global Consensus Meeting, which was convened to develop global consensus on (1) classification of chronic gastritis and duodenitis, (2) clinical distinction of dyspepsia caused by Helicobacter pylori from functional dyspepsia, (3) appropriate dia

  18. A consensus on criteria for cure of acromegaly

    NARCIS (Netherlands)

    A. Giustina (Andrea); P. Chanson (Philippe); M.D. Bronstein; A. Klibanski; S.W.J. Lamberts (Steven); F.F. Casanueva; P. Trainer; E. Ghigo (Ezio); K.K.Y. Ho; S. Melmed (Shlomo)

    2010-01-01

    textabstractObjective: The Acromegaly Consensus Group met in April 2009 to revisit the guidelines on criteria for cure as defined in 2000. Participants: Participants included 74 neurosurgeons and endocrinologists with extensive experience of treating acromegaly. Evidence/Consensus Process: Relevant

  19. The Consensus Definition Redefined from a Representational Perspective

    Science.gov (United States)

    Zand Scholten, Annemarie

    2012-01-01

    This paper presents the author's critique to Paul E. Newton's article titled "Clarifying the consensus definition of validity." In his article, Newton not only clarifies but also redefines the consensus definition of validity. In this redefinition he omits the term "construct" and introduces the term "measurement." Both omission and introduction…

  20. Treatment of adrenocorticotropin-dependent cushing's syndrome: A consensus statement

    NARCIS (Netherlands)

    B.M.K. Biller; A. Grossman (Ashley Barry); P.M. Stewart; S. Melmed (Shlomo); X. Bertagna; J. Bertherat (Jerome); M. Buchfelder; A. Colao (Annamaria); A.R. Hermus (Ad); L.J. Hofland (Leo); A. Klibanski; A. Lacroix; J.R. Lindsay; J. Newell-Price; L.K. Nieman; S. Petersenn; N. Sonino; G.K. Stalla (Günter); B. Swearingen; M.L. Vance; J.A.H. Wass (John); M. Boscaro

    2008-01-01

    textabstractObjective: Our objective was to evaluate the published literature and reach a consensus on the treatment of patients with ACTH-dependent Cushing's syndrome, because there is no recent consensus on the management of this rare disorder. Participants: Thirty-two leading endocrinologists,

  1. Treatment of adrenocorticotropin-dependent Cushing's syndrome: a consensus statement.

    NARCIS (Netherlands)

    Grossman, A.B.; Stewart, P.M.; Melmed, S.; Bertagna, X.; Bertherat, J.; Buchfelder, M.; Colao, A.; Hermus, A.R.M.M.; Hofland, L.J.; Klibanski, A.; Lacroix, A.; Lindsay, J.R.; Newell-Price, J.; Nieman, L.K.; Petersenn, S.; Sonino, N.; Stalla, G.K.; Swearingen, B.; Vance, M.L.; Wass, J.A.; Boscaro, M.

    2008-01-01

    OBJECTIVE: Our objective was to evaluate the published literature and reach a consensus on the treatment of patients with ACTH-dependent Cushing's syndrome, because there is no recent consensus on the management of this rare disorder. PARTICIPANTS: Thirty-two leading endocrinologists, clinicians,

  2. A consensus on criteria for cure of acromegaly

    NARCIS (Netherlands)

    A. Giustina (Andrea); P. Chanson (Philippe); M.D. Bronstein; A. Klibanski; S.W.J. Lamberts (Steven); F.F. Casanueva; P. Trainer; E. Ghigo (Ezio); K.K.Y. Ho; S. Melmed (Shlomo)

    2010-01-01

    textabstractObjective: The Acromegaly Consensus Group met in April 2009 to revisit the guidelines on criteria for cure as defined in 2000. Participants: Participants included 74 neurosurgeons and endocrinologists with extensive experience of treating acromegaly. Evidence/Consensus Process: Relevant

  3. Kyoto global consensus report on Helicobacter pylori gastritis

    NARCIS (Netherlands)

    K. Sugano (Kentaro); J. Tack (Jan); E.J. Kuipers (Ernst); D.Y. Graham (David Y.); E. El-Omar; S. Miura (Soichiro); K. Haruma (Ken); M. Asaka (Masahiro); N. Uemura (Naomi); P. Malfertheiner; T. Azuma (Takeshi); F. Bazzoli (Franco); F.K.-L. Chan (Francis Ka-Leung); M. Chen (Minhu); N. Chiba (Naoki); T. Chiba (Tsutomu); L.G. Vas Coelho (Luiz Gonzaga); F. Di Mario (Francesco); K.M. Fock (Kwong Ming); Y. Fukuda (Yasuhiro); R.M. Genta (Robert Maximilian); K.-L. Goh (Khean-Lee); P.H. Katelaris (Peter Harry); M. Kato (Mototsugu); T. Kawai (Takashi); R. Kushima (Ryuji); V. Mahachai (Varocha); T. Matsuhisa (Takeshi); H. Miwa (Hiroto); K. Murakami (Kazunari); C. O'Morain (C.); M. Rugge (Massimo); K. Sato (Kiichi); T. Shimoyama (Tadashi); T. Sugiyama (Toshiro); H. Suzuki (Hidekazu); K. Yagi (Kazuyoshi); M.-S. Wu (Ming-Shiang); M. Ito (Masanori); N. Kim (Nayoung); T. Furuta (Takahisa); F. Mégraud (Francis); A. Shiotani (Akiko); T. Kamada (Tomonori)

    2015-01-01

    textabstractObjective To present results of the Kyoto Global Consensus Meeting, which was convened to develop global consensus on (1) classification of chronic gastritis and duodenitis, (2) clinical distinction of dyspepsia caused by Helicobacter pylori from functional dyspepsia, (3) appropriate

  4. Consensus Statement National Consensus Workshop on Management of SAM Children through Medical Nutrition Therapy.

    Science.gov (United States)

    Sachdev, H P S; Kapil, Umesh; Vir, Sheila

    2010-08-01

    Severe acute malnutrition (SAM) is an important preventable and treatable cause of morbidity and mortality in children below five years of age in India. The concerned stakeholders are not in agreement about the role of product based medical nutrition therapy in the management of this condition. In November 2009, a National Consensus Workshop was organized by the Department of Human Nutrition, All India Institute of Medical Sciences, New Delhi in collaboration with the Department of Pediatrics and Clinical Epidemiology, Sitaram Bhartia Institute of Science and Research, New Delhi, and the Sub-specialty Chapter on Nutrition, Indian Academy of Pediatrics. Presentations by eminent national and international scientists, the ensuing discussions, and opinions expressed by the participants provided the basic framework for drafting the consensus statement. The draft of the consensus statement was circulated to all the participants; it underwent two revisions after consideration of their comments. (i) Critically appraise the current global evidence on the utility of Medical Nutrition Therapy (MNT) for the management of SAM in under five children; (ii) Formulate a consensus amongst stakeholders regarding the need to introduce product based MNT for the management of SAM in under five children in India; (iii) Identify research priorities for MNT for the management of SAM in under five children in India; and (iv)Ascertain potential challenges for introducing product based MNT in India, if consensus opinion identifies such a need. Guidelines related to the role of MNT in management of children suffering from SAM are presented. Global and regional data document the effectiveness of MNT using ready-to-use therapeutic foods (RUTF) and locally formulated products. Adequate caution should be exercised to ensure that MNT for SAM does not interfere with measures for the holistic prevention of childhood undernutrition. Indian manufacture of RUTF is feasible, and can be scaled up. Product

  5. Establishing Consensus Turbulence Statistics for Hot Subsonic Jets

    Science.gov (United States)

    Bridges, James; Werner, Mark P.

    2010-01-01

    Many tasks in fluids engineering require knowledge of the turbulence in jets. There is a strong, although fragmented, literature base for low order statistics, such as jet spread and other meanvelocity field characteristics. Some sources, particularly for low speed cold jets, also provide turbulence intensities that are required for validating Reynolds-averaged Navier-Stokes (RANS) Computational Fluid Dynamics (CFD) codes. There are far fewer sources for jet spectra and for space-time correlations of turbulent velocity required for aeroacoustics applications, although there have been many singular publications with various unique statistics, such as Proper Orthogonal Decomposition, designed to uncover an underlying low-order dynamical description of turbulent jet flow. As the complexity of the statistic increases, the number of flows for which the data has been categorized and assembled decreases, making it difficult to systematically validate prediction codes that require high-level statistics over a broad range of jet flow conditions. For several years, researchers at NASA have worked on developing and validating jet noise prediction codes. One such class of codes, loosely called CFD-based or statistical methods, uses RANS CFD to predict jet mean and turbulent intensities in velocity and temperature. These flow quantities serve as the input to the acoustic source models and flow-sound interaction calculations that yield predictions of far-field jet noise. To develop this capability, a catalog of turbulent jet flows has been created with statistics ranging from mean velocity to space-time correlations of Reynolds stresses. The present document aims to document this catalog and to assess the accuracies of the data, e.g. establish uncertainties for the data. This paper covers the following five tasks: Document acquisition and processing procedures used to create the particle image velocimetry (PIV) datasets. Compare PIV data with hotwire and laser Doppler

  6. Randomized Consensus Processing over Random Graphs: Independence and Convergence

    CERN Document Server

    Shi, Guodong

    2011-01-01

    Various consensus algorithms over random networks have been investigated in the literature. In this paper, we focus on the role that randomized individual decision-making plays to consensus seeking under stochastic communications. At each time step, each node will independently choose to follow the consensus algorithm, or to stick to current state by a simple Bernoulli trial with time-dependent success probabilities. This node decision strategy characterizes the random node-failures on a communication networks, or a biased opinion selection in the belief evolution over social networks. Connectivity-independent and arc-independent graphs are defined, respectively, to capture the fundamental nature of random network processes with regard to the convergence of the consensus algorithms. A series of sufficient and/or necessary conditions are given on the success probability sequence for the network to reach a global consensus with probability one under different stochastic connectivity assumptions, by which a comp...

  7. DASACT: A decision aiding software for axiomatic consensus theory.

    Science.gov (United States)

    Domenach, Florent; Tayari, Ali

    2016-01-01

    There have been various attempts, solutions, and approaches towards constructing an appropriate consensus tree based on a given set of phylogenetic trees. However, for practitioners, it is not always clear, for a given data set, which of these would create the most relevant consensus tree. In this paper, we introduce an open-source software called DASACT (Decision Aiding Software for Axiomatic Consensus Theory) created to assist practitioners on choosing the most appropriate consensus function. It is based on an exhaustive evaluation of axiomatic properties and consensus functions, which define the knowledge space as a concept lattice. Using a selection of axiomatic properties provided by the user, it is able to aid the user in choosing the most suitable function. DASACT is freely available at http://www.cs.unic.ac.cy/florent/software.htm. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Evolution of the average avalanche shape with the universality class.

    Science.gov (United States)

    Laurson, Lasse; Illa, Xavier; Santucci, Stéphane; Tore Tallakstad, Ken; Måløy, Knut Jørgen; Alava, Mikko J

    2013-01-01

    A multitude of systems ranging from the Barkhausen effect in ferromagnetic materials to plastic deformation and earthquakes respond to slow external driving by exhibiting intermittent, scale-free avalanche dynamics or crackling noise. The avalanches are power-law distributed in size, and have a typical average shape: these are the two most important signatures of avalanching systems. Here we show how the average avalanche shape evolves with the universality class of the avalanche dynamics by employing a combination of scaling theory, extensive numerical simulations and data from crack propagation experiments. It follows a simple scaling form parameterized by two numbers, the scaling exponent relating the average avalanche size to its duration and a parameter characterizing the temporal asymmetry of the avalanches. The latter reflects a broken time-reversal symmetry in the avalanche dynamics, emerging from the local nature of the interaction kernel mediating the avalanche dynamics.

  9. Cooperative control of multi-agent systems a consensus region approach

    CERN Document Server

    Li, Zhongkui

    2014-01-01

    Distributed controller design is generally a challenging task, especially for multi-agent systems with complex dynamics, due to the interconnected effect of the agent dynamics, the interaction graph among agents, and the cooperative control laws. Cooperative Control of Multi-Agent Systems: A Consensus Region Approach offers a systematic framework for designing distributed controllers for multi-agent systems with general linear agent dynamics, linear agent dynamics with uncertainties, and Lipschitz nonlinear agent dynamics.Beginning with an introduction to cooperative control and graph theory,

  10. Sea Surface Temperature Average_SST_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sea surface temperature collected via satellite imagery from http://www.esrl.noaa.gov/psd/data/gridded/data.noaa.ersst.html and averaged for each region using ArcGIS...

  11. Appeals Council Requests - Average Processing Time

    Data.gov (United States)

    Social Security Administration — This dataset provides annual data from 1989 through 2015 for the average processing time (elapsed time in days) for dispositions by the Appeals Council (AC) (both...

  12. Average Vegetation Growth 1990 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1990 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  13. Average Vegetation Growth 1997 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1997 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  14. Average Vegetation Growth 1992 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1992 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  15. Average Vegetation Growth 2001 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 2001 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  16. Average Vegetation Growth 1995 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1995 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  17. Average Vegetation Growth 2000 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 2000 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  18. Average Vegetation Growth 1998 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1998 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  19. Average Vegetation Growth 1994 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1994 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  20. MN Temperature Average (1961-1990) - Line

    Data.gov (United States)

    Minnesota Department of Natural Resources — This data set depicts 30-year averages (1961-1990) of monthly and annual temperatures for Minnesota. Isolines and regions were created using kriging and...

  1. Average Vegetation Growth 1996 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1996 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  2. Average Vegetation Growth 2005 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 2005 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  3. Average Vegetation Growth 1993 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1993 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  4. MN Temperature Average (1961-1990) - Polygon

    Data.gov (United States)

    Minnesota Department of Natural Resources — This data set depicts 30-year averages (1961-1990) of monthly and annual temperatures for Minnesota. Isolines and regions were created using kriging and...

  5. Spacetime Average Density (SAD) Cosmological Measures

    CERN Document Server

    Page, Don N

    2014-01-01

    The measure problem of cosmology is how to obtain normalized probabilities of observations from the quantum state of the universe. This is particularly a problem when eternal inflation leads to a universe of unbounded size so that there are apparently infinitely many realizations or occurrences of observations of each of many different kinds or types, making the ratios ambiguous. There is also the danger of domination by Boltzmann Brains. Here two new Spacetime Average Density (SAD) measures are proposed, Maximal Average Density (MAD) and Biased Average Density (BAD), for getting a finite number of observation occurrences by using properties of the Spacetime Average Density (SAD) of observation occurrences to restrict to finite regions of spacetimes that have a preferred beginning or bounce hypersurface. These measures avoid Boltzmann brain domination and appear to give results consistent with other observations that are problematic for other widely used measures, such as the observation of a positive cosmolo...

  6. A practical guide to averaging functions

    CERN Document Server

    Beliakov, Gleb; Calvo Sánchez, Tomasa

    2016-01-01

    This book offers an easy-to-use and practice-oriented reference guide to mathematical averages. It presents different ways of aggregating input values given on a numerical scale, and of choosing and/or constructing aggregating functions for specific applications. Building on a previous monograph by Beliakov et al. published by Springer in 2007, it outlines new aggregation methods developed in the interim, with a special focus on the topic of averaging aggregation functions. It examines recent advances in the field, such as aggregation on lattices, penalty-based aggregation and weakly monotone averaging, and extends many of the already existing methods, such as: ordered weighted averaging (OWA), fuzzy integrals and mixture functions. A substantial mathematical background is not called for, as all the relevant mathematical notions are explained here and reported on together with a wealth of graphical illustrations of distinct families of aggregation functions. The authors mainly focus on practical applications ...

  7. Rotational averaging of multiphoton absorption cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Friese, Daniel H., E-mail: daniel.h.friese@uit.no; Beerepoot, Maarten T. P.; Ruud, Kenneth [Centre for Theoretical and Computational Chemistry, University of Tromsø — The Arctic University of Norway, N-9037 Tromsø (Norway)

    2014-11-28

    Rotational averaging of tensors is a crucial step in the calculation of molecular properties in isotropic media. We present a scheme for the rotational averaging of multiphoton absorption cross sections. We extend existing literature on rotational averaging to even-rank tensors of arbitrary order and derive equations that require only the number of photons as input. In particular, we derive the first explicit expressions for the rotational average of five-, six-, and seven-photon absorption cross sections. This work is one of the required steps in making the calculation of these higher-order absorption properties possible. The results can be applied to any even-rank tensor provided linearly polarized light is used.

  8. Rotational averaging of multiphoton absorption cross sections

    Science.gov (United States)

    Friese, Daniel H.; Beerepoot, Maarten T. P.; Ruud, Kenneth

    2014-11-01

    Rotational averaging of tensors is a crucial step in the calculation of molecular properties in isotropic media. We present a scheme for the rotational averaging of multiphoton absorption cross sections. We extend existing literature on rotational averaging to even-rank tensors of arbitrary order and derive equations that require only the number of photons as input. In particular, we derive the first explicit expressions for the rotational average of five-, six-, and seven-photon absorption cross sections. This work is one of the required steps in making the calculation of these higher-order absorption properties possible. The results can be applied to any even-rank tensor provided linearly polarized light is used.

  9. Monthly snow/ice averages (ISCCP)

    Data.gov (United States)

    National Aeronautics and Space Administration — September Arctic sea ice is now declining at a rate of 11.5 percent per decade, relative to the 1979 to 2000 average. Data from NASA show that the land ice sheets in...

  10. Average Annual Precipitation (PRISM model) 1961 - 1990

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer shows polygons of average annual precipitation in the contiguous United States, for the climatological period 1961-1990. Parameter-elevation...

  11. Symmetric Euler orientation representations for orientational averaging.

    Science.gov (United States)

    Mayerhöfer, Thomas G

    2005-09-01

    A new kind of orientation representation called symmetric Euler orientation representation (SEOR) is presented. It is based on a combination of the conventional Euler orientation representations (Euler angles) and Hamilton's quaternions. The properties of the SEORs concerning orientational averaging are explored and compared to those of averaging schemes that are based on conventional Euler orientation representations. To that aim, the reflectance of a hypothetical polycrystalline material with orthorhombic crystal symmetry was calculated. The calculation was carried out according to the average refractive index theory (ARIT [T.G. Mayerhöfer, Appl. Spectrosc. 56 (2002) 1194]). It is shown that the use of averaging schemes based on conventional Euler orientation representations leads to a dependence of the result from the specific Euler orientation representation that was utilized and from the initial position of the crystal. The latter problem can be overcome partly by the introduction of a weighing factor, but only for two-axes-type Euler orientation representations. In case of a numerical evaluation of the average, a residual difference remains also if a two-axes type Euler orientation representation is used despite of the utilization of a weighing factor. In contrast, this problem does not occur if a symmetric Euler orientation representation is used as a matter of principle, while the result of the averaging for both types of orientation representations converges with increasing number of orientations considered in the numerical evaluation. Additionally, the use of a weighing factor and/or non-equally spaced steps in the numerical evaluation of the average is not necessary. The symmetrical Euler orientation representations are therefore ideally suited for the use in orientational averaging procedures.

  12. Cosmic Inhomogeneities and the Average Cosmological Dynamics

    OpenAIRE

    Paranjape, Aseem; Singh, T. P.

    2008-01-01

    If general relativity (GR) describes the expansion of the Universe, the observed cosmic acceleration implies the existence of a `dark energy'. However, while the Universe is on average homogeneous on large scales, it is inhomogeneous on smaller scales. While GR governs the dynamics of the \\emph{in}homogeneous Universe, the averaged \\emph{homogeneous} Universe obeys modified Einstein equations. Can such modifications alone explain the acceleration? For a simple generic model with realistic ini...

  13. Average Bandwidth Allocation Model of WFQ

    Directory of Open Access Journals (Sweden)

    Tomáš Balogh

    2012-01-01

    Full Text Available We present a new iterative method for the calculation of average bandwidth assignment to traffic flows using a WFQ scheduler in IP based NGN networks. The bandwidth assignment calculation is based on the link speed, assigned weights, arrival rate, and average packet length or input rate of the traffic flows. We prove the model outcome with examples and simulation results using NS2 simulator.

  14. Consensus for Multiagent Systems with Nonlinear Dynamics and Time Delays Using a Two-Hop Relay Adaptive Method

    Directory of Open Access Journals (Sweden)

    Qian Cao

    2014-01-01

    Full Text Available This paper investigates the consensus problem for multiagent systems with nonlinear dynamics and time delays. A distributed adaptive consensus protocol is proposed in which the time delays are explicitly included in the adaptive algorithm. It is shown that the resultant closed loop system involves doubly larger time delays, making the stability analysis nontrivial. Stability condition on maximum tolerable time delay is established and controlled by the proposed two-hop adaptive algorithm. The explicit expression of the delay margin is derived and analyzed in the frequency domain. Both the agent state errors and the estimation parameter errors converge to zero. A simulation example is illustrated to verify the theory results.

  15. The Delphi Technique: Making Sense of Consensus

    Directory of Open Access Journals (Sweden)

    Chia-Chien Hsu

    2007-08-01

    Full Text Available The Delphi technique is a widely used and accepted method for gathering data from respondents within their domain of expertise. The technique is designed as a group communication process which aims to achieve a convergence of opinion on a specific real-world issue. The Delphi process has been used in various fields of study such as program planning, needs assessment, policy determination, and resource utilization to develop a full range of alternatives, explore or expose underlying assumptions, as well as correlate judgments on a topic spanning a wide range of disciplines. The Delphi technique is well suited as a method for consensus-building by using a series of questionnaires delivered using multiple iterations to collect data from a panel of selected subjects. Subject selection, time frames for conducting and completing a study, the possibility of low response rates, and unintentionally guiding feedback from the respondent group are areas which should be considered when designing and implementing a Delphi study.

  16. National consensus on geriatric immunization 2011.

    Science.gov (United States)

    2012-01-01

    As the growth of elderly population increases, the number of geriatric patients who may demand health care services is also increasing since the elderly are more vulnerable to various conditions of acute illnesses. Upper respiratory tract infections are the leading cause of death and the most significant cause that impairs quality of life in the elderly. Upper respiratory tract infections and influenza are common in the elderly and may develop into pneumonia. Considering the high morbidity and mortality rates related to pneumonia in the elderly, it is important to have prevention strategies. A delay in diagnosis due to non-specific signs and symptoms of pneumonia in the elderly has demanded greater concern on the importance of pneumonia prevention strategies. Influenza and pneumonia impair quality of life in the elderly, resulted in decreased functional status (ADL scores) during infection and recovery period. With increasing antibiotic resistance, the management may be complicated as it may lead to conditions that reduce quality of life and cause high mortality rate. Therefore, immunization is very important as the prevention strategy against influenza and or pneumonia, reducing the incidence as well as the complication. The consensus has been made in order to provide immunization against influenza and pneumonia for elderly population in Indonesia. It is expected that by 2025, about 60% of the elderly in Indonesia would have immunization against influenza and 50% of them would have immunization against pneumonia annually.

  17. Consensus document on European brain research.

    Science.gov (United States)

    Olesen, Jes; Baker, Mary G; Freund, Tamas; di Luca, Monica; Mendlewicz, Julien; Ragan, Ian; Westphal, Manfred

    2006-08-01

    countries, greater collaboration between industry, academia and patient organisations, and increased investment in the brain sciences. The EBC was formed in 2002 to bring together scientists, clinicians, the pharmaceutical industry, charities and patient organisations from all over Europe to campaign for these goals. It takes a novel, bottom-up approach to research policy, and in developing this consensus document, it aims to promote a greater and more focused effort in this area, to improve public understanding of the brain sciences and above all, to support brain research as a priority under the European Commission's Seventh Framework Programme (FP7, 2007-2013). The research programme outlined here was first conceived by the EBC board. An outline was sent to all member organisations and a number of individual experts for comments. Following that, a table of contents was developed. The 45 research themes were written by groups of experts from across Europe who represent a wide range of disciplines. Each one contains a proposal for future research on a specific brain-related theme which the EBC believes could form the basis of one or more integrated projects or strategic targeted research projects (STREP) funded under FP7. The EBC has deliberately focused on the major diseases and then described the basic research needed to understand and treat or perhaps even cure those diseases. The programme is therefore constructed "from man to molecule" and not the other way round, with equal importance attached to basic and clinical research. The EBC suggests that each of the proposed integrated projects or STREP should be awarded a budget in the order of Euro 10 to 15 million. In addition, brain research should be treated as an important element of many other parts of FP7, such as the European Research Council and research programmes on information technology and the causes of violence. Any research programme that concerns human behaviour should, by definition, take account of brain

  18. Sarcopenia With Limited Mobility: An International Consensus

    Science.gov (United States)

    Morley, John E.; Abbatecola, Angela Marie; Argiles, Josep M.; Baracos, Vickie; Bauer, Juergen; Bhasin, Shalender; Cederholm, Tommy; Stewart Coats, Andrew J.; Cummings, Steven R.; Evans, William J.; Fearon, Kenneth; Ferrucci, Luigi; Fielding, Roger A.; Guralnik, Jack M.; Harris, Tamara B.; Inui, Akio; Kalantar-Zadeh, Kamyar; Kirwan, Bridget-Anne; Mantovani, Giovanni; Muscaritoli, Maurizio; Newman, Anne B.; Rossi-Fanelli, Filippo; Rosano, Giuseppe M. C.; Roubenoff, Ronenn; Schambelan, Morris; Sokol, Gerald H.; Storer, Thomas W.; Vellas, Bruno; von Haehling, Stephan; Yeh, Shing-Shing; Anker, Stefan D.

    2016-01-01

    A consensus conference convened by the Society of Sarcopenia, Cachexia and Wasting Disorders has concluded that “Sarcopenia, ie, reduced muscle mass, with limited mobility” should be considered an important clinical entity and that most older persons should be screened for this condition. “Sarcopenia with limited mobility” is defined as a person with muscle loss whose walking speed is equal to or less than 1 m/s or who walks less than 400 m during a 6-minute walk, and who has a lean appendicular mass corrected for height squared of 2 standard deviations or more below the mean of healthy persons between 20 and 30 years of age of the same ethnic group. The limitation in mobility should not clearly be a result of otherwise defined specific diseases of muscle, peripheral vascular disease with intermittent claudication, central and peripheral nervous system disorders, or cachexia. Clinically significant interventions are defined as an increase in the 6-minute walk of at least 50 meters or an increase of walking speed of at least 0.1 m/s. “A word is not a crystal, transparent and unchanged; it is the skin of a living thought and may vary greatly in color and content according to the circumstances and the time when it is used.”—Oliver Wendell Holmes PMID:21640657

  19. Canadian Asthma Consensus Conference Summary of Recommendations

    Directory of Open Access Journals (Sweden)

    Pierre Ernst

    1996-01-01

    Full Text Available The Asthma Committee of the Canadian Thoracic Society invited a group of Canadian physicians with a particular interest in asthma to meet in Montebello, Quebec, March 9-12, 1995 to arrive at a consensus statement on the optimal approach to the management of asthma in the pediatric and adult ambulatory care settings. The societies and associations represented are listed in the appendix with the names of the contributors to this document. The objectives of the Montebello conference were: 1. To review the current ambulatory care management of asthma in Canada; 2. To develop guidelines with the participation of family physicians and specialists; 3. To develop guidelines which are evidence-based; 4. In creating evidence-based guidelines to focus attention on aspects of asthma management that are currently not supported by randomized controlled trials; 5. To develop strategies that allow for the implementation of rational guidelines at a local level. Recommendations were based on a critical review of the scientific literature by small groups prior to the meeting and are categorized according to the strength of the scientific evidence supporting each recommendation (Table 1.

  20. Current Consensus Guidelines for Treatment of Neurocysticercosis

    Science.gov (United States)

    García, Hector H.; Evans, Carlton A. W.; Nash, Theodore E.; Takayanagui, Osvaldo M.; White, A. Clinton; Botero, David; Rajshekhar, Vedantam; Tsang, Victor C. W.; Schantz, Peter M.; Allan, James C.; Flisser, Ana; Correa, Dolores; Sarti, Elsa; Friedland, Jon S.; Martinez, S. Manuel; Gonzalez, Armando E.; Gilman, Robert H.; Del Brutto, Oscar H.

    2002-01-01

    Taenia solium neurocysticercosis is a common cause of epileptic seizures and other neurological morbidity in most developing countries. It is also an increasingly common diagnosis in industrialized countries because of immigration from areas where it is endemic. Its clinical manifestations are highly variable and depend on the number, stage, and size of the lesions and the host's immune response. In part due to this variability, major discrepancies exist in the treatment of neurocysticercosis. A panel of experts in taeniasis/cysticercosis discussed the evidence on treatment of neurocysticercosis for each clinical presentation, and we present the panel's consensus and areas of disagreement. Overall, four general recommendations were made: (i) individualize therapeutic decisions, including whether to use antiparasitic drugs, based on the number, location, and viability of the parasites within the nervous system; (ii) actively manage growing cysticerci either with antiparasitic drugs or surgical excision; (iii) prioritize the management of intracranial hypertension secondary to neurocysticercosis before considering any other form of therapy; and (iv) manage seizures as done for seizures due to other causes of secondary seizures (remote symptomatic seizures) because they are due to an organic focus that has been present for a long time. PMID:12364377

  1. Identification of consensus binding sites clarifies FMRP binding determinants.

    Science.gov (United States)

    Anderson, Bart R; Chopra, Pankaj; Suhl, Joshua A; Warren, Stephen T; Bassell, Gary J

    2016-08-19

    Fragile X mental retardation protein (FMRP) is a multifunctional RNA-binding protein with crucial roles in neuronal development and function. Efforts aimed at elucidating how FMRP target mRNAs are selected have produced divergent sets of target mRNA and putative FMRP-bound motifs, and a clear understanding of FMRP's binding determinants has been lacking. To clarify FMRP's binding to its target mRNAs, we produced a shared dataset of FMRP consensus binding sequences (FCBS), which were reproducibly identified in two published FMRP CLIP sequencing datasets. This comparative dataset revealed that of the various sequence and structural motifs that have been proposed to specify FMRP binding, the short sequence motifs TGGA and GAC were corroborated, and a novel TAY motif was identified. In addition, the distribution of the FCBS set demonstrates that FMRP preferentially binds to the coding region of its targets but also revealed binding along 3' UTRs in a subset of target mRNAs. Beyond probing these putative motifs, the FCBS dataset of reproducibly identified FMRP binding sites is a valuable tool for investigating FMRP targets and function. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Terminal Sliding Mode-Based Consensus Tracking Control for Networked Uncertain Mechanical Systems on Digraphs.

    Science.gov (United States)

    Chen, Gang; Song, Yongduan; Guan, Yanfeng

    2016-12-29

    This brief investigates the finite-time consensus tracking control problem for networked uncertain mechanical systems on digraphs. A new terminal sliding-mode-based cooperative control scheme is developed to guarantee that the tracking errors converge to an arbitrarily small bound around zero in finite time. All the networked systems can have different dynamics and all the dynamics are unknown. A neural network is used at each node to approximate the local unknown dynamics. The control schemes are implemented in a fully distributed manner. The proposed control method eliminates some limitations in the existing terminal sliding-mode-based consensus control methods and extends the existing analysis methods to the case of directed graphs. Simulation results on networked robot manipulators are provided to show the effectiveness of the proposed control algorithms.

  3. Consensus of Euler-Lagrange systems networked by sampled-data information with probabilistic time delays.

    Science.gov (United States)

    Ma, Chao; Shi, Peng; Zhao, Xudong; Zeng, Qingshuang

    2015-06-01

    This paper investigates the consensus problem of multiple Euler-Lagrange systems under directed topology. Unlike the common assumptions on continuous-time information exchanges, a more realistic sampled-data communication strategy is proposed with probabilistic occurrence of time-varying delays. Both of the sampling period and the delays are assumed to be time-varying, which is more general in some practical situations. In addition, the relative coordinate derivative information is not required in the distributed controllers such that the communication network burden can be further reduced. In particular, a distinct feature of the proposed scheme lies in the fact that it can effectively reduce the energy consumption. By employing the stochastic analysis techniques, sufficient conditions are established to guarantee that the consensus can be achieved. Finally, a numerical example is provided to illustrate the applicability and benefits of the theoretical results.

  4. Multi-Sensor Consensus Estimation of State, Sensor Biases and Unknown Input.

    Science.gov (United States)

    Zhou, Jie; Liang, Yan; Yang, Feng; Xu, Linfeng; Pan, Quan

    2016-09-01

    This paper addresses the problem of the joint estimation of system state and generalized sensor bias (GSB) under a common unknown input (UI) in the case of bias evolution in a heterogeneous sensor network. First, the equivalent UI-free GSB dynamic model is derived and the local optimal estimates of system state and sensor bias are obtained in each sensor node; Second, based on the state and bias estimates obtained by each node from its neighbors, the UI is estimated via the least-squares method, and then the state estimates are fused via consensus processing; Finally, the multi-sensor bias estimates are further refined based on the consensus estimate of the UI. A numerical example of distributed multi-sensor target tracking is presented to illustrate the proposed filter.

  5. Event-triggered Kalman-consensus filter for two-target tracking sensor networks.

    Science.gov (United States)

    Su, Housheng; Li, Zhenghao; Ye, Yanyan

    2017-06-24

    This paper is concerned with the problem of event-triggered Kalman-consensus filter for two-target tracking sensor networks. According to the event-triggered protocol and the mean-square analysis, a suboptimal Kalman gain matrix is derived and a suboptimal event-triggered distributed filter is obtained. Based on the Kalman-consensus filter protocol, all sensors which only depend on its neighbors' information can track their corresponding targets. Furthermore, utilizing Lyapunov method and matrix theory, some sufficient conditions are presented for ensuring the stability of the system. Finally, a simulation example is presented to verify the effectiveness of the proposed event-triggered protocol. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  6. The consensus in the two-feature two-state one-dimensional Axelrod model revisited

    CERN Document Server

    Biral, Elias J P; Fontanari, José F

    2015-01-01

    The Axelrod model for the dissemination of culture exhibits a rich spatial distribution of cultural domains, which depends on the values of the two model parameters: $F$, the number of cultural features and $q$, the number of states each feature can assume. In the one-dimensional model with $F=q=2$, which is equivalent to the constrained voter model, Monte Carlo simulations indicate the existence of multicultural absorbing configurations in which at least one macroscopic domain coexist with a multitude of microscopic ones in the thermodynamic limit. However, rigorous analytical results for an infinite system indicate the existence of only monocultural or consensus configurations at equilibrium. Here we show that this disagreement is due simply to the different orders that the time-asymptotic limit and the thermodynamic limit are taken in those two approaches. In addition, we show how the consensus-only result can be derived using Monte Carlo simulations of finite chains.

  7. Neural network-based adaptive consensus tracking control for multi-agent systems under actuator faults

    Science.gov (United States)

    Zhao, Lin; Jia, Yingmin

    2016-06-01

    In this paper, a distributed output feedback consensus tracking control scheme is proposed for second-order multi-agent systems in the presence of uncertain nonlinear dynamics, external disturbances, input constraints, and partial loss of control effectiveness. The proposed controllers incorporate reduced-order filters to account for the unmeasured states, and the neural networks technique is implemented to approximate the uncertain nonlinear dynamics in the synthesis of control algorithms. In order to compensate the partial loss of actuator effectiveness faults, fault-tolerant parts are included in controllers. Using the Lyapunov approach and graph theory, it is proved that the controllers guarantee a group of agents that simultaneously track a common time-varying state of leader, even when the state of leader is available only to a subset of the members of a group. Simulation results are provided to demonstrate the effectiveness of the proposed consensus tracking method.

  8. Modeling and Flocking Consensus Analysis for Large-Scale UAV Swarms

    Directory of Open Access Journals (Sweden)

    Li Bing

    2013-01-01

    Full Text Available Recently, distributed coordination control of the unmanned aerial vehicle (UAV swarms has been a particularly active topic in intelligent system field. In this paper, through understanding the emergent mechanism of the complex system, further research on the flocking and the dynamic characteristic of UAV swarms will be given. Firstly, this paper analyzes the current researches and existent problems of UAV swarms. Afterwards, by the theory of stochastic process and supplemented variables, a differential-integral model is established, converting the system model into Volterra integral equation. The existence and uniqueness of the solution of the system are discussed. Then the flocking control law is given based on artificial potential with system consensus. At last, we analyze the stability of the proposed flocking control algorithm based on the Lyapunov approach and prove that the system in a limited time can converge to the consensus direction of the velocity. Simulation results are provided to verify the conclusion.

  9. Averaged controllability of parameter dependent conservative semigroups

    Science.gov (United States)

    Lohéac, Jérôme; Zuazua, Enrique

    2017-02-01

    We consider the problem of averaged controllability for parameter depending (either in a discrete or continuous fashion) control systems, the aim being to find a control, independent of the unknown parameters, so that the average of the states is controlled. We do it in the context of conservative models, both in an abstract setting and also analysing the specific examples of the wave and Schrödinger equations. Our first result is of perturbative nature. Assuming the averaging probability measure to be a small parameter-dependent perturbation (in a sense that we make precise) of an atomic measure given by a Dirac mass corresponding to a specific realisation of the system, we show that the averaged controllability property is achieved whenever the system corresponding to the support of the Dirac is controllable. Similar tools can be employed to obtain averaged versions of the so-called Ingham inequalities. Particular attention is devoted to the 1d wave equation in which the time-periodicity of solutions can be exploited to obtain more precise results, provided the parameters involved satisfy Diophantine conditions ensuring the lack of resonances.

  10. Average Temperatures in the Southwestern United States, 2000-2015 Versus Long-Term Average

    Data.gov (United States)

    U.S. Environmental Protection Agency — This indicator shows how the average air temperature from 2000 to 2015 has differed from the long-term average (1895–2015). To provide more detailed information,...

  11. The Consensus Project: Survey of the peer-reviewed scientific literature to determine the degree of consensus on anthropogenic climate change

    Science.gov (United States)

    Nuccitelli, D. A.; Cook, J.; Jokimäki, A.; Skuce, A. G.; Green, S. A.; Painting, R.; Morrison, G. W.; Reitano, R.; Richardson, M.; Honeycutt, R.; Winkler, B.; Tamblyn, G.

    2012-12-01

    -98% AGW consensus found in previous studies (Doran and Zimmerman 2009 and Anderegg et al. 2010). 2011 had the most total papers surveyed at 1,683. An average of 3.7 rejections per year were identified, with a maximum of 9 in 2011. Endorsements averaged 187 per year, with a maximum of 521 in 2011. These results represent the most comprehensive confirmation of the AGW consensus to date.

  12. Public Awareness of the Scientific Consensus on Climate

    Directory of Open Access Journals (Sweden)

    Lawrence C. Hamilton

    2016-11-01

    Full Text Available Questions about climate change elicit some of the widest political divisions of any items on recent U.S. surveys. Severe polarization affects even basic questions about the reality of anthropogenic climate change (ACC, or whether most scientists agree that humans are changing the Earth’s climate. Statements about scientific consensus have been contentious among social scientists, with some arguing for consensus awareness as a “gateway cognition” that leads to greater public acceptance of ACC, but others characterizing consensus messaging (deliberate communication about the level of scientific agreement as a counterproductive tactic that exacerbates polarization. A series of statewide surveys, with nationwide benchmarks, repeated questions about the reality of ACC and scientific consensus many times over 2010 to 2016. These data permit tests for change in beliefs and polarization. ACC and consensus beliefs have similar trends and individual background predictors. Both rose gradually by about 10 points over 2010 to 2016, showing no abrupt shifts that might correspond to events such as scientific reports, leadership statements, or weather. Growing awareness of the scientific consensus, whether from deliberate messaging or the cumulative impact of many studies and publicly engaged scientists, provides the most plausible explanation for this rise in both series. In state-level data, the gap between liberal and conservative views on the reality of ACC did not widen over this period, whereas the liberal–conservative gap regarding existence of a scientific consensus narrowed.

  13. Cosmic structure, averaging and dark energy

    CERN Document Server

    Wiltshire, David L

    2013-01-01

    These lecture notes review the theoretical problems associated with coarse-graining the observed inhomogeneous structure of the universe at late epochs, of describing average cosmic evolution in the presence of growing inhomogeneity, and of relating average quantities to physical observables. In particular, a detailed discussion of the timescape scenario is presented. In this scenario, dark energy is realized as a misidentification of gravitational energy gradients which result from gradients in the kinetic energy of expansion of space, in the presence of density and spatial curvature gradients that grow large with the growth of structure. The phenomenology and observational tests of the timescape model are discussed in detail, with updated constraints from Planck satellite data. In addition, recent results on the variation of the Hubble expansion on < 100/h Mpc scales are discussed. The spherically averaged Hubble law is significantly more uniform in the rest frame of the Local Group of galaxies than in t...

  14. Books average previous decade of economic misery.

    Directory of Open Access Journals (Sweden)

    R Alexander Bentley

    Full Text Available For the 20(th century since the Depression, we find a strong correlation between a 'literary misery index' derived from English language books and a moving average of the previous decade of the annual U.S. economic misery index, which is the sum of inflation and unemployment rates. We find a peak in the goodness of fit at 11 years for the moving average. The fit between the two misery indices holds when using different techniques to measure the literary misery index, and this fit is significantly better than other possible correlations with different emotion indices. To check the robustness of the results, we also analysed books written in German language and obtained very similar correlations with the German economic misery index. The results suggest that millions of books published every year average the authors' shared economic experiences over the past decade.

  15. Benchmarking statistical averaging of spectra with HULLAC

    Science.gov (United States)

    Klapisch, Marcel; Busquet, Michel

    2008-11-01

    Knowledge of radiative properties of hot plasmas is important for ICF, astrophysics, etc When mid-Z or high-Z elements are present, the spectra are so complex that one commonly uses statistically averaged description of atomic systems [1]. In a recent experiment on Fe[2], performed under controlled conditions, high resolution transmission spectra were obtained. The new version of HULLAC [3] allows the use of the same model with different levels of details/averaging. We will take advantage of this feature to check the effect of averaging with comparison with experiment. [1] A Bar-Shalom, J Oreg, and M Klapisch, J. Quant. Spectros. Rad. Transf. 65, 43 (2000). [2] J. E. Bailey, G. A. Rochau, C. A. Iglesias et al., Phys. Rev. Lett. 99, 265002-4 (2007). [3]. M. Klapisch, M. Busquet, and A. Bar-Shalom, AIP Conference Proceedings 926, 206-15 (2007).

  16. Stochastic Averaging and Stochastic Extremum Seeking

    CERN Document Server

    Liu, Shu-Jun

    2012-01-01

    Stochastic Averaging and Stochastic Extremum Seeking develops methods of mathematical analysis inspired by the interest in reverse engineering  and analysis of bacterial  convergence by chemotaxis and to apply similar stochastic optimization techniques in other environments. The first half of the text presents significant advances in stochastic averaging theory, necessitated by the fact that existing theorems are restricted to systems with linear growth, globally exponentially stable average models, vanishing stochastic perturbations, and prevent analysis over infinite time horizon. The second half of the text introduces stochastic extremum seeking algorithms for model-free optimization of systems in real time using stochastic perturbations for estimation of their gradients. Both gradient- and Newton-based algorithms are presented, offering the user the choice between the simplicity of implementation (gradient) and the ability to achieve a known, arbitrary convergence rate (Newton). The design of algorithms...

  17. Books average previous decade of economic misery.

    Science.gov (United States)

    Bentley, R Alexander; Acerbi, Alberto; Ormerod, Paul; Lampos, Vasileios

    2014-01-01

    For the 20(th) century since the Depression, we find a strong correlation between a 'literary misery index' derived from English language books and a moving average of the previous decade of the annual U.S. economic misery index, which is the sum of inflation and unemployment rates. We find a peak in the goodness of fit at 11 years for the moving average. The fit between the two misery indices holds when using different techniques to measure the literary misery index, and this fit is significantly better than other possible correlations with different emotion indices. To check the robustness of the results, we also analysed books written in German language and obtained very similar correlations with the German economic misery index. The results suggest that millions of books published every year average the authors' shared economic experiences over the past decade.

  18. High Average Power Yb:YAG Laser

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, L E; Beach, R J; Payne, S A

    2001-05-23

    We are working on a composite thin-disk laser design that can be scaled as a source of high brightness laser power for tactical engagement and other high average power applications. The key component is a diffusion-bonded composite comprising a thin gain-medium and thicker cladding that is strikingly robust and resolves prior difficulties with high average power pumping/cooling and the rejection of amplified spontaneous emission (ASE). In contrast to high power rods or slabs, the one-dimensional nature of the cooling geometry and the edge-pump geometry scale gracefully to very high average power. The crucial design ideas have been verified experimentally. Progress this last year included: extraction with high beam quality using a telescopic resonator, a heterogeneous thin film coating prescription that meets the unusual requirements demanded by this laser architecture, thermal management with our first generation cooler. Progress was also made in design of a second-generation laser.

  19. Analytic treatment of tipping points for social consensus in large random networks.

    Science.gov (United States)

    Zhang, W; Lim, C; Szymanski, B K

    2012-12-01

    We introduce a homogeneous pair approximation to the naming game (NG) model by deriving a six-dimensional Open Dynamics Engine (ODE) for the two-word naming game. Our ODE reveals the change in dynamical behavior of the naming game as a function of the average degree {k} of an uncorrelated network. This result is in good agreement with the numerical results. We also analyze the extended NG model that allows for presence of committed nodes and show that there is a shift of the tipping point for social consensus in sparse networks.

  20. Waif goodbye! Average-size female models promote positive body image and appeal to consumers.

    Science.gov (United States)

    Diedrichs, Phillippa C; Lee, Christina

    2011-10-01

    Despite consensus that exposure to media images of thin fashion models is associated with poor body image and disordered eating behaviours, few attempts have been made to enact change in the media. This study sought to investigate an effective alternative to current media imagery, by exploring the advertising effectiveness of average-size female fashion models, and their impact on the body image of both women and men. A sample of 171 women and 120 men were assigned to one of three advertisement conditions: no models, thin models and average-size models. Women and men rated average-size models as equally effective in advertisements as thin and no models. For women with average and high levels of internalisation of cultural beauty ideals, exposure to average-size female models was associated with a significantly more positive body image state in comparison to exposure to thin models and no models. For men reporting high levels of internalisation, exposure to average-size models was also associated with a more positive body image state in comparison to viewing thin models. These findings suggest that average-size female models can promote positive body image and appeal to consumers.