Parametric control of flexible timing through low-dimensional neural manifolds

Biological brains possess an unparalleled ability to generalize adaptive behavioral responses from only a few examples. How neural processes enable this capacity to extrapolate is a fundamental open question. A prominent but underexplored hypothesis suggests that generalization is facilitated by a low-dimensional organization of collective neural activity. Here we tested this hypothesis in the framework of flexible timing tasks where dynamics play a key role. Examining trained recurrent neural networks we found that confining the dynamics to a low-dimensional subspace allowed tonic inputs to parametrically control the overall input-output transform and enabled smooth extrapolation to inputs well beyond the training range. Reverse-engineering and theoretical analyses demonstrated that this parametric control of extrapolation relies on a mechanism where tonic inputs modulate the dynamics along non-linear manifolds in activity space while preserving their geometry. Comparisons with neural data from behaving monkeys confirmed the geometric and dynamical signatures of this mechanism.

NEW APPROACH FOR DETECTING SLIGHT SHIFT ON PROCESS MEAN IN CHIP RESISTOR PRODUCTION

This article highlights an alternative approach to identify a slight shift of the process mean for resistor production. Commonly, the industries use exponentially weighted moving average (EWMA) or classic I-MR charts for this kind of product. The parametric control chart consists of few underlying assumptions, especially observations that come from a normal distribution. A misleading conclusion was mainly made when non-normal distributed data were analyzed using a parametric control chart. A chip resistor manufacturing company provided the data for the study for future quality monitoring purposes. This study aims to determine a more appropriate analysis method according to the characteristics of the chip resistor data distribution. This article discusses the results of implementing one of the nonparametric methods that are still rarely known. The company’s current I-MR, corrective I-MR, parametric EWMA, and NPEWMA-SR control charts are used and compared in the analysis part. In the comparison, the I-MR control chart cannot detect a slight shift in the process mean. In contrast, the parametric EWMA control chart is not robust for data from a non-normal population. Since the data was not naturally from a normally distributed population, the nonparametric control chart is more appropriate, and the NPEWMA-SR control chart is suggested.

Design and Experimental Validation of Radio Access Network Controller Prototype for Multi-RAT Technologies with Scheduler Strategies

The main aspects of this paper are to show the involvement towards coordination strategies amongst multiple RATs and integration of parametric control of higher MAC and upper layer network protocols. Moreover, we also evaluate and examine the possibility to take advantage of the fact of using interworking concepts such as lightweight Internet protocol (LWIP) and LTE-WLAN aggregation (LWA) while making the scheduling decisions. Such a solution would contribute to the software-defined networking (SDN) approach, where multi-RAT aware scheduler adapts to dynamic channel conditions to provide robustness against severe real-time channel conditions. Finally, we provide comparative analysis of multi- RAT scenarios and evaluate the QoE performance of different scheduling algorithms with SINR based information centric LWA switching and QoE-aware LWA switching by using RANC.

Design and Experimental Validation of Radio Access Network Controller Prototype for Multi-RAT Technologies with Scheduler Strategies

The main aspects of this paper are to show the involvement towards coordination strategies amongst multiple RATs and integration of parametric control of higher MAC and upper layer network protocols. Moreover, we also evaluate and examine the possibility to take advantage of the fact of using interworking concepts such as lightweight Internet protocol (LWIP) and LTE-WLAN aggregation (LWA) while making the scheduling decisions. Such a solution would contribute to the software-defined networking (SDN) approach, where multi-RAT aware scheduler adapts to dynamic channel conditions to provide robustness against severe real-time channel conditions. Finally, we provide comparative analysis of multi- RAT scenarios and evaluate the QoE performance of different scheduling algorithms with SINR based information centric LWA switching and QoE-aware LWA switching by using RANC.

A Novel Surface Parametric Method and Its Application to Aerodynamic Design Optimization of Axial Compressors

A novel parametric control method for the compressor blade, the full-blade surface parametric method, is proposed in this paper. Compared with the traditional parametric method, the method has good surface smoothness and construction convenience while maintaining low-dimensional characteristics, and compared with the semi-blade surface parametric method, the proposed method has a larger degree of geometric deformation freedom and can account for changes in both the suction surface and pressure surface. Compared with the semi-blade surface parametric method, the method only has four more control parameters for each blade, so it does not significantly increase the optimization time. The effectiveness of this novel parametric control method has been verified in the aerodynamic optimization field of compressors by an optimization case of Stage35 (a single-stage transonic axial compressor) under multi-operating conditions. The optimization case has brought the following results: the adiabatic efficiency of the optimized blade at design speed is 1.4% higher than that of the original one and the surge margin 2.9% higher, while at off-design speed, the adiabatic efficiency is improved by 0.6% and the surge margin by 1.3%.

Effect of Different Forms of Periodic Piecewise Linear Forces on Duffing Oscillator

The paper highlights the effect of different forms of periodic piecewise linear forces in the ubiquitous Duffing oscillator equation. The external periodic piecewise linear forces considered are Triangular, Hat, Trapezium, Quadratic and Rectangular. With the aid of some numerical simulation tools such as bifurcation diagram, phase portrait and Poincare´ map, the different routes to chaos and various strange attractors are found to occur due to the applied forces. The effect of an ε-parametric control force in the Duffing system is also analyzed. To characterize the regular and chaotic behaviours of this system, the maximal Lyapunov exponent is employed.