Search results for "cluster [track data analysis]"
showing 10 items of 1171 documents
Business models in Spanish industry : a taxonomy-based efficacy analysis
2010
The present study provides a conceptualization of the business model construct from which a multi-dimensional evaluation tool is developed that provides the basis for drawing up a taxonomy and analysing its comparative efficacy. The empirical data was obtained from a sampling of 159 Spanish business organisations. The cluster analysis revealed the existence of four business models that were designated as “multidivisional”, “integrated”, “hybrid” and “network”. The results also indicate that the adoption of a certain business model is not enough to attain superior performance, highlighting the need to consider other contingent factors.
Data-Driven Interactive Multiobjective Optimization Using a Cluster-Based Surrogate in a Discrete Decision Space
2019
In this paper, a clustering based surrogate is proposed to be used in offline data-driven multiobjective optimization to reduce the size of the optimization problem in the decision space. The surrogate is combined with an interactive multiobjective optimization approach and it is applied to forest management planning with promising results. peerReviewed
Beyond Tandem Analysis: Joint Dimension Reduction and Clustering in R
2019
We present the R package clustrd which implements a class of methods that combine dimension reduction and clustering of continuous or categorical data. In particular, for continuous data, the package contains implementations of factorial K-means and reduced K-means; both methods combine principal component analysis with K-means clustering. For categorical data, the package provides MCA K-means, i-FCB and cluster correspondence analysis, which combine multiple correspondence analysis with K-means. Two examples on real data sets are provided to illustrate the usage of the main functions.
Clusterization and Strong Coulpled-Channels Effects in Deuteron Interaction with 9Be Nuclei
2019
Angular distributions of protons, deuterons, tritons and alphaparticles emitted in the d + 9Be reaction at Elab=19.5 and 35.0 MeV have been measured. The elastic scattering channel is analysed in the framework of both the Optical Model and the Coupled-Channel approach. The interaction potential of the d + 9Be system is calculated in the framework of the Double-Folding model using the α + α + n three-body wave function of the 9Be nucleus. The (d, p) and (d, t) one-nucleon-transfer reactions are analysed within the coupledreaction-channel approach. The spectroscopic amplitudes for the different nuclear cluster configurations are calculated. Differential cross sections for the reaction channel…
Transient stability simulation of a fixed speed wind turbine by Matlab/Simulink
2007
This paper describes the dynamic behavior of a typical fixed speed wind turbine connected to the grid; the model is developed in the simulation tool Matlab/Simulink and created as a modular structure. The pitch control system is used for stabilization of the wind turbine at grid faults. In this way, voltage stability of the system with grid-connected wind turbines can be improved by using blade-angle control for a temporary reduction of the wind turbine power during a short-circuit fault in the grid. This paper shows a new variable control for maintaining of voltage stability, when a three-phase fault is applied close to the wind turbine and cleared by disconnecting the affected line. In th…
Dynamics and extraction of quantum discord in a multipartite open system
2011
We consider a multipartite system consisting of two noninteracting qubits each embedded in a single-mode leaky cavity, in turn connected to an external bosonic reservoir. Initially, we take the two qubits in an entangled state while the cavities and the reservoirs have zero photons. We investigate, in this six-partite quantum system, the transfer of quantum discord from the qubits to the cavities and reservoirs. We show that this transfer occurs also when the cavities are not entangled. Moreover, we discuss how quantum discord can be extracted from the cavities and transferred to distant systems by traveling leaking photons, using the input-output theory.
Discrete cortical representations and their stability in the presence of synaptic turnover
2015
Population imaging in mouse auditory cortex revealed clustering of neural responses to brief complex sounds: the activity of a local population typically falls close to one out of a small number of observed states [1]. These clusters appear to group sets of auditory stimuli into a discrete set of activity patterns and could thereby form the basis for representations of sound categories. However, to be useful for the brain, such representations should be robust against fluctuations in the underlying circuitry, which are significant even in the absences of any explicit learning paradigm [2]. Here we introduce a novel firing rate based circuit model of mouse auditory cortex to study the emerge…
Comparative parallel characterization of particle populations with two mass spectrometric systems LAMPAS 2 and SPASS
2006
Abstract Two transportable laser mass spectrometers, Single Particle Analysis and Sizing System (SPASS) and Laser Mass Analyzer for Particles in the Airborne State (LAMPAS 2), have been applied to investigate the dependence of spectra patterns on instrumental parameters and data evaluation procedures in an inter-comparison experiment. Laboratory experiments showed the spectral response of both instruments for mineral particles before and after heterogeneous reactions. During a period of 47 h, both instruments determined size and chemical composition of several thousand single particles of an ambient particle population. Time-resolved evaluation (1-h resolution) of specific ion signals, whic…
Population differentiation of the European pond turtle (Emys orbicularis) in Poland inferred by the analysis of mitochondrial and microsatellite DNA …
2013
We investigated the genetic diversity of Polish populations of the European pond turtle (Emys orbicularis) using complete sequences of the mitochondrial cytochrome b gene and allelic variation at thirteen microsatellite loci. We collected data from 146 turtles from 28 locations covering most of the species’ range in Poland. Our results showed a low haplotype diversity and high levels of microsatellite diversity in all populations. We applied two Bayesian approaches using the multilocus data and determined relationships of mtDNA haplotypes by constructing a parsimony network. We observed relatively consistent results of the two Bayesian clustering methods and largely concordant differentiati…
Sperm kinematics and morphometric subpopulations analysis with CASA systems: a review
2019
Sperm kinematics and morphometric subpopulations analysis with CASA systems: a review. The subjective evaluation of seminal quality has given way to the use of objective assessment techniques by CASA technology (computer-assisted semen analysis). The application of principal components (PC) and clustering methods to reveal subpopulations of spermatozoa is a powerful tool to evaluate raw semen and processed cell suspensions, but not many researchers are aware of the technique. PC analysis is a multivariate statistical method that reduces the number of variables used in subsequent calculations used to describe the data. By integrating the original variables according to their coherence in a d…