749 research outputs found
A network processor for a learning based routing protocol
Recently, Cognitive Packet Networks (CPN) is proposed as an alternative to the IP based network architectures and shows similarity with the discrete active networks. In CPN, there is no routing table, instead reinforcement learning (Random Neural Networks) is used to route packets. CPN routes packets based on QoS, using measurements that are constantly collected by packets and deposited in mailboxes at routers. The applicability of the CPN concept has been demonstrated through several software implementations. However, higher data traffic and increasing packet processing demands require the implementation of this new network architecture in hardware. In this paper, we present a network processor architecture which supports this learning based protocol. ©2004 IEEE
Monopole equations on 8-manifolds with Spin(7) holonomy
We construct a consistent set of monopole equations on eight-manifolds with
Spin(7) holonomy. These equations are elliptic and admit non-trivial solutions
including all the 4-dimensional Seiberg-Witten solutions as a special case.Comment: 14 pages, LATEX (No figures
Coopetition as a Small Business Strategy: Implications for Performance
This paper explores coopetition, a strategy that combines cooperation and competition in addressing relationships between firms. We examine the underlying nature of coopetition, and evaluate the extent to which it represents a relevant strategy for small firms. Inherent problems are identified when attempting to collaborate with competitors. We propose an approach to measuring the coopetitive tendencies of small firms. The measurement approach centers on three underlying dimensions: mutual benefit, trust, and commitment. Applying this approach, we assess the relationship between coopetition and firm performance. Based on a survey of 647 small firms in Turkey, a strong, positive relationship is identified. Theoretical and managerial implications are drawn from the findings
Zonal Jets as Transport Barriers in Planetary Atmospheres
The connection between transport barriers and potential vorticity (PV)
barriers in PV-conserving flows is investigated with a focus on zonal jets in
planetary atmospheres. A perturbed PV-staircase model is used to illustrate
important concepts. This flow consists of a sequence of narrow eastward and
broad westward zonal jets with a staircase PV structure; the PV-steps are at
the latitudes of the cores of the eastward jets. Numerically simulated
solutions to the quasigeostrophic PV conservation equation in a perturbed
PV-staircase flow are presented. These simulations reveal that both eastward
and westward zonal jets serve as robust meridional transport barriers. The
surprise is that westward jets, across which the background PV gradient
vanishes, serve as robust transport barriers. A theoretical explanation of the
underlying barrier mechanism is provided. It is argued that transport barriers
near the cores of westward zonal jets, across which the background PV gradient
is small, are found in Jupiter's midlatitude weather layer and in the Earth's
summer hemisphere subtropical stratosphere.Comment: Accepted for publication in JA
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Maternal metabolic factors during pregnancy predict early childhood growth trajectories and obesity risk: the CANDLE Study.
BackgroundWe investigated the individual and additive effects of three modifiable maternal metabolic factors, including pre-pregnancy overweight/obesity, gestational weight gain (GWG), and gestational diabetes mellitus (GDM), on early childhood growth trajectories and obesity risk.MethodsA total of 1425 mother-offspring dyads (953 black and 472 white) from a longitudinal birth cohort were included in this study. Latent class growth modeling was performed to identify the trajectories of body mass index (BMI) from birth to 4 years in children. Poisson regression models were used to examine the associations between the maternal metabolic risk factors and child BMI trajectories and obesity risk at 4 years.ResultsWe identified three discrete BMI trajectory groups, characterized as rising-high-BMI (12.6%), moderate-BMI (61.0%), or low-BMI (26.4%) growth. Both maternal pre-pregnancy obesity (adjusted relative risk [adjRR]â=â1.96; 95% confidence interval [CI]: 1.36-2.83) and excessive GWG (adjRRâ=â1.71, 95% CI: 1.13-2.58) were significantly associated with the rising-high-BMI trajectory, as manifested by rapid weight gain during infancy and a stable but high BMI until 4 years. All three maternal metabolic indices were significantly associated with childhood obesity at age 4 years (adjRR for pre-pregnancy obesityâ=â2.24, 95% CI: 1.62-3.10; adjRR for excessive GWGâ=â1.46, 95% CI: 1.01-2.09; and adjRR for GDMâ=â2.14, 95%â=â1.47-3.12). In addition, risk of rising-high BMI trajectory or obesity at age 4 years was stronger among mothers with more than one metabolic risk factor. We did not observe any difference in these associations by race.ConclusionMaternal pre-pregnancy obesity, excessive GWG, and GDM individually and jointly predict rapid growth and obesity at age 4 years in offspring, regardless of race. Interventions targeting maternal obesity and metabolism may prevent or slow the rate of development of childhood obesity
Design and implementation of a random neural network routing engine
Random neural network (RNN) is an analytically tractable spiked neural network model that has been implemented in software for a wide range of applications for over a decade. This paper presents the hardware implementation of the RNN model. Recently, cognitive packet networks (CPN) is proposed as an alternative packet network architecture where there is no routing table, instead RNN based reinforcement learning is used to route packets. Particularly, we describe implementation details for the RNN based routing engine of a CPN network processor chip: the smart packet processor (SPP). The SPP is a dual port device that stores, modifies, and interprets the defining characteristics of multiple RNN models. In addition to hardware design improvements over the software implementation such as dual access memory, output calculation step, reduced output calculation module, this paper introduces a major modification to the reinforcement learning algorithm used in the original CPN specification such that the number of weight terms are reduced from 2n2 to 2n. This not only yields significant memory savings, but it also simplifies the calculations for the steady state probabilities (neuron outputs in RNN). Simulations have been conducted to confirm the proper functionality for the isolated SPP design as well as for the multiple SPP\u27s in a networked environment
Any -state solutions of the Hulth\'en potential by the asymptotic iteration method
In this article, we present the analytical solution of the radial
Schr\"{o}dinger equation for the Hulth\'{e}n potential within the framework of
the asymptotic iteration method by using an approximation to the centrifugal
potential for any states. We obtain the energy eigenvalues and the
corresponding eigenfunctions for different screening parameters. The wave
functions are physical and energy eigenvalues are in good agreement with the
results obtained by other methods for different values. In order to
demonstrate this, the results of the asymptotic iteration method are compared
with the results of the supersymmetry, the numerical integration, the
variational and the shifted 1/N expansion methods.Comment: 14 pages and 1 figur
Transient conjugated forced convection heat transfer in thick walled pipes and minipipes with time periodically changing convective boundary condition
Transient conjugated heat transfer in thick walled pipes with
thermally developing laminar flow is analyzed. Effects of axial
fluid conduction as well as radial and axial wall conduction are
involved. The problem is solved numerically in a two regional
pipe, initially isothermal, for which the ambient temperature in
the downstream region suddenly begins to change periodically
in time. A parametric study is done to investigate the effects of
five defining dimensionless parameters of the problem, which
are namely; wall thickness ratio, wall-to-fluid thermal
conductivity ratio, wall-to-fluid thermal diffusivity ratio, the
Peclet number, the Biot number, and also the effect of the value
of the angular frequency.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers
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Effect of different storage conditions on analytical and sensory quality of thermally processed milk based germinated Foxtail millet porridge
Foxtail millet porridge was prepared using germinated grains and milk and was evaluated for its storage stability after thermal processing at Ultra High Temperatures (UHT) of 142 oC for 5 s and Retort processing temperatures of 121.5 oC for 15 min. Various physical, chemical and microbial changes of the porridge were studied for a storage period of 180 days at 25 ± 1 oC. Using consumer perception and survival analysis, the predicted shelf life of the UHT treated and retort processed foxtail millet porridge samples stored at 25 ± 1 oC was found to be 186 ± 9 days and 245 ± 15 days, respectively. Also, data from consumer liking, profiling, physical, chemical and microbial parameters showed significant changes (p < 0.05) in the thermally treated packaged porridge samples over time. As the consumer overall acceptability decreased, the detection of positive attributes (Thick and uniformly coloured texture and appearance; grainy mouth texture; caramel taste and aroma) in the porridge decreased, while the detection of negative attributes (Uneven, decoloured, and curdled texture and appearance; sticky mouth texture; cooked, sour and off smell; cooked, sour and off taste) increased. The present study could establish a significant difference (p < 0.05) in the storage induced properties of UHT and retort processed porridge samples. The analytical evaluation of foxtail millet porridge found that UHT treated porridge was better in quality, but consumers preferred retort processed porridge
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