1041031
Distributed synchrony
Data implying that neurons can communicate with synchronous volleys are di'cult to reconcile with the bulk of single unit recordings which do not show synchrony yet reveal substantial correlations with animal behavior. Our simulations reconcile these two sets of results by sharing a synchronous signal among groups of neurons in a way that the average signal through any particular neuron exhibits conventional receptive ,eld properties. The simulation models a subset of the connections between the LGN and V1 and shows that synchronous computation at a high ,ring rate can appear at an individual cell as random spikes at a lower rate. c © 2002 Elsevier Science B.V. All rights reserved.
12306777
A single spike model of predictive coding
22666885
A single-spike model of predictive coding
Abstract The standard cortical model assumes that the meaning of a neuron's signal is contained in its firing rate. While that model has been used to interpret a voluminous amount of experimental data, it does not address the question of timing, or how recipient neurons can decode this signal in time to predict behavioral results. We propose a model based on coincident firing of large groups of neurons. We show using an example of predictive coding, how the cortex can support vast amounts of non-interfering parallel computation.
17488685
Large deviations and the generalized processor sharing scheduling for a two-queue system
We establish the optimal asymptotic decay rate of per-session queue length tail distributions for a two-queue system where a single constant rate server serves the two queues using the Generalized Processor Sharing (GPS) scheduling discipline. The result is obtained using the sample-path large deviation principle and has implications in call admission control for high-speed communication networks.
18883067
On selection of candidate paths for proportional routing
QoS routing involves selection of paths for flows based on the knowledge at network nodes about the availability of resources along paths, and the QoS requirements of flows. Several QoS routing schemes have been proposed that differ in the way they gather information about the network state and select paths using this information. Most of these schemes can be categorized as best path routing where a source node selects the "best" path for each incoming flow based on its current view of the global network state. It has been shown that best path routing schemes require frequent exchange of network state, imposing both communication overhead on the network and processing overheads on the core routers. On the other hand, proportional routing schemes proportion incoming flows among a set of candidate paths. Two key questions that arise under proportional routing are how to select candidate paths and how to proportion flows among candidate paths. We propose a scheme that selects a few widest disjoint paths as candidates and equalizes the blocking probabilities of the candidate paths. We show that our proportional routing approach yields higher throughput with lower overhead than best path routing approach. Furthermore, we present a method for aggregating the state of an area and extend the proportional routing approach to provide hierarchical routing across multiple areas in a large network.
6801587
Performance analysis of k-fold multicast networks
Multicast involves transmitting information from a single source to multiple destinations, and is an important operation in high-performance networks. A k-fold multicast network was recently proposed as a cost-effective solution to providing better quality-of-service functions in supporting real-world multicast applications. To give a quantitative basis for network designers to determine the suitable value of system parameter k under different traffic loads, in this paper, we propose an analytical model for the performance of k-fold multicast networks under Poisson traffic. We first give the stationary distribution of network states, and then derive the throughput and blocking probability of the network. We also conduct extensive simulations to validate the analytical model, and the results show that the analytical model is very accurate under the assumptions made. The analytical and simulation results reveal that by increasing the fold of the network, network throughput increases very fast when the fanouts of multicast connections are relatively small, compared with the network size.
45941410
The optimal service time allocation of a versatile server to queue jobs and stochastically available non-queue jobs of different types
Abstract In this paper, we consider a service system in which the server can process N + 1 different types of jobs. Jobs of type 0 are generated randomly according to a Poisson stream. Jobs of types 1 to N are non-queue types which may or may not be available for completion by the server. To optimally allocate the server's time to these jobs, we formulate a finite state semi-Markov decision process model to this environment. With this model, the optimal stationary policies can be numerically determined via a policy-iteration algorithm. We also discuss the practical applications of this model to tele-service and tele-marketing operations.
33273119
On Symmetrical Multilevel Diversity Coding