Search results for "Linear"
showing 10 items of 7165 documents
Are attachment dimensions associated with infertility-related stress in couples undergoing their first IVF treatment? A study on the individual and c…
2012
study question: Are attachment anxiety and avoidance dimensions in female and male partners in couples seeking infertility treat- ment associated with her and his infertility-related stress? summary answer: Attachment dimensions are significantly associated with several aspects of infertility stress in couples undergoing IVF treatment. what is known and what this paper adds: Attachment dimensions of anxiety and avoidance (where highly anxious individuals fear rejection and are preoccupied with maintaining proximity to their partner and highly avoidant individuals are uncomfortable with intimacy and prefer to maintain distance from their partner) may influence the well being of individuals u…
Definition of a fiber macro-model for nonlinear analysis of infilled frames
2017
A common way to model infill-frame interaction is the use equivalent strut macromodels. In most cases these are compression only resistant truss elements defined with a multi-linear axial-force / axial-displacement law. The main difficulty in using this approach is to correctly calibrate such a force-displacement curve (slope of ascending and post-peak branches, critical yielding, peak and residual forces) because of the large number of variables (mechanical and elastic properties of materials) and the different possible damage mechanisms activated for the frame-infill system. Another possible way is using fiber-section elements as diagonal struts. In this case the force-displacement law is…
Comparing two methods of analysis of single-ring infiltrometer data for a sandy–loam soil
2009
Abstract The single-ring pressure infiltrometer (PI) with the steady-state Two-Ponding-Depth (TPD) application method were developed to simultaneously determine the saturated soil hydraulic conductivity, K fs , and the α ⁎-parameter in the field. Methods of analysis of transient PI data are also available but they have received little testing so far. The transient WU method and the TPD method were compared for a sandy-loam soil. A linearization technique of the infiltration curve yielded more reliable K fs and α ⁎ results (i.e., falling within expected ranges) than a non-linear optimization technique. The WU method gave both positive and reasonable K fs and α ⁎ values for all infiltration t…
Banking Competition, Collateral Constraints and Optimal Monetary Policy
2013
We analyze optimal monetary policy in a model with two distinct financial frictions. First, borrowing is subject to collateral constraints. Second, credit flows are intermediated by monopolistically competitive banks, thus giving rise to endogenous lending spreads. We show that, up to a second order approximation, welfare maximization is equivalent to stabilization of four goals: inflation, output gap, the consumption gap between constrained and unconstrained agents, and the distribution of the collateralizable asset between both groups. Following both financial and non-financial shocks, the optimal monetary policy commitment implies a short-run trade-off between stabilization goals. Such p…
Unconventional monetary policy reaction functions: evidence from the US
2020
Abstract We specify unconventional monetary policy reaction functions for the Fed using linear and nonlinear econometric frameworks. We find that nonstandard policy measures are largely driven by the dynamics of inflation and the output gap, with the effect being particularly strong during QE rounds. Moreover, we uncover the presence of asymmetry and regime dependence in central bank’s actions since the global financial crisis, especially concerning the response of the term spread and the shadow short rate to the growth rate of central bank reserves. From a policy perspective and given the lack of a systematic response of monetary policy to asset price growth in nonstandard times, our findi…
Delay-dependent exponential stabilization of positive 2D switched state-delayed systems in the Roesser model
2014
This paper deals with the controller synthesis for a class of positive two-dimensional (2D) switched delay systems described by the Roesser model. This kind of systems has the property that the states take nonnegative values whenever the initial boundaries are nonnegative, some delay-dependent sufficient conditions for the exponential stability of positive 2D switched systems with state delays are given. Furthermore, the design of positive state feedback controller under which the resulting closed-loop system meets the requirements of positivity and exponential stability is presented in terms of linear matrix inequalities (LMIs). An example is included to illustrate the effectiveness of the…
An overview of incremental feature extraction methods based on linear subspaces
2018
Abstract With the massive explosion of machine learning in our day-to-day life, incremental and adaptive learning has become a major topic, crucial to keep up-to-date and improve classification models and their corresponding feature extraction processes. This paper presents a categorized overview of incremental feature extraction based on linear subspace methods which aim at incorporating new information to the already acquired knowledge without accessing previous data. Specifically, this paper focuses on those linear dimensionality reduction methods with orthogonal matrix constraints based on global loss function, due to the extensive use of their batch approaches versus other linear alter…
An ant colony optimization-based fuzzy predictive control approach for nonlinear processes
2015
In this paper, a new approach for designing an adaptive fuzzy model predictive control (AFMPC) based on the ant colony optimization (ACO) is proposed. On-line adaptive fuzzy identification is introduced to identify the system parameters. These parameters are used to calculate the objective function based on a predictive approach and structure of RST control. Then the optimization problem is solved based on an ACO algorithm, used at the optimization process in AFMPC to determine optimal controller parameters of RST control. The utility of the proposed controller is demonstrated by applying it to two nonlinear processes, where the proposed approach provides better performances compared with p…
Network-based H∞ output feedback control for uncertain stochastic systems
2013
This paper investigates the problem of network-based Floc, output feedback control for a class of stochastic nonlinear systems. A novel model is proposed to describe the systems taken into two sides of communication channels in the network environment, which is more general than one side of communication channel. The design procedure of observer-based controller is presented, which, guarantees the asymptotic stability in the mean square of the resulting closed-loop system with an H-infinity performance. Finally, a crane example is utilized to show the effectiveness and potential of the developed techniques. Refereed/Peer-reviewed
An efficient method for clustered multi-metric learning
2019
Abstract Distance metric learning, which aims at finding a distance metric that separates examples of one class from examples of the other classes, is the key to the success of many machine learning tasks. Although there has been an increasing interest in this field, learning a global distance metric is insufficient to obtain satisfactory results when dealing with heterogeneously distributed data. A simple solution to tackle this kind of data is based on kernel embedding methods. However, it quickly becomes computationally intractable as the number of examples increases. In this paper, we propose an efficient method that learns multiple local distance metrics instead of a single global one.…