Functionplane—A new approach to simple structure rotation

Psychometrika ◽  
1974 ◽  
Vol 39 (1) ◽  
pp. 37-51 ◽  
Author(s):  
Jeffrey Owen Katz ◽  
F. James Rohlf
Methodology ◽  
2019 ◽  
Vol 15 (Supplement 1) ◽  
pp. 43-60 ◽  
Author(s):  
Florian Scharf ◽  
Steffen Nestler

Abstract. It is challenging to apply exploratory factor analysis (EFA) to event-related potential (ERP) data because such data are characterized by substantial temporal overlap (i.e., large cross-loadings) between the factors, and, because researchers are typically interested in the results of subsequent analyses (e.g., experimental condition effects on the level of the factor scores). In this context, relatively small deviations in the estimated factor solution from the unknown ground truth may result in substantially biased estimates of condition effects (rotation bias). Thus, in order to apply EFA to ERP data researchers need rotation methods that are able to both recover perfect simple structure where it exists and to tolerate substantial cross-loadings between the factors where appropriate. We had two aims in the present paper. First, to extend previous research, we wanted to better understand the behavior of the rotation bias for typical ERP data. To this end, we compared the performance of a variety of factor rotation methods under conditions of varying amounts of temporal overlap between the factors. Second, we wanted to investigate whether the recently proposed component loss rotation is better able to decrease the bias than traditional simple structure rotation. The results showed that no single rotation method was generally superior across all conditions. Component loss rotation showed the best all-round performance across the investigated conditions. We conclude that Component loss rotation is a suitable alternative to simple structure rotation. We discuss this result in the light of recently proposed sparse factor analysis approaches.


2020 ◽  
Vol 34 (25) ◽  
pp. 2050264
Author(s):  
Xionggui Tang ◽  
Fang Meng

A novel scheme for tunable optofluidic optical coupler is proposed by combining directional coupling waveguide structures with microfluidic channel. The normalized optical power at two output ports can be dynamically manipulated by controlling the refractive index of liquid mixture in microfluidic channel. Its optical performance is numerically investigated by employing the beam propagation method (BPM). The simulated results show that the dynamic range of over 45 dB, and optical loss of below 0.06 dB can be easily achieved, and furthermore the dependence of polarization states and operation wavelength in the range from 1500 nm to 1600 nm are very low in our designed device. In addition, the tunable optofluidic coupler has advantages including simple structure and large fabrication tolerance. Accordingly, our proposed device offers a new approach for manipulating optical power output, which has wide potential application in optofluidic systems.


2013 ◽  
Vol 341-342 ◽  
pp. 1351-1362
Author(s):  
Fang Lin Luo

Multilevel DC/AC Inverters have various structures. They have many advantages. Unfortunately, most existing inverters content too many components (independent/floating batteries/sources, diodes, Capacitors and switches). The author introduces the "Laddered Multilevel DC/AC Inverters in this paper that is new approach of the development in this area. Their simple structure and clear operation are obviously different from the existing inverters. Its application in Solar Panel Energy Systems is successful. The simulation and experimental results strongly support our design. We believe that these inverters will draw much attention over the world, and be applied in other renewable energy systems.


2016 ◽  
Vol 138 (10) ◽  
Author(s):  
Federica Grossi ◽  
Roberto Zanasi

The aim of this work is to give a new approach to obtain compact dynamic thermal models suitable for a variety of systems where the heat transfer can be caused by conduction, internal convection (not at the boundary), and evaporation/condensation of water. The structural properties of the proposed dynamic model are presented and discussed in this paper. These properties guarantee conservation of energy and mass within the system, thus giving a good confidence in the correctness of the model. This paper shows that the proposed model has a simple structure, can be easily implemented in simulink, and provides simulation times much shorter compared with those usually obtained using CFD programs. The proposed model proves to be suitable for real-time simulations and for control design purposes.


Symmetry ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 384 ◽  
Author(s):  
Ali Namakin ◽  
Seyyed Najafi ◽  
Mohammad Fallah ◽  
Mehrdad Javadi

There are numerous models for solving the efficiency evaluation in data envelopment analysis (DEA) with fuzzy input and output data. However, because of the limitation of those strategies, they cannot be implemented for solving fully fuzzy DEA (FFDEA). Furthermore, in real-world problems with imprecise data, fuzziness is not sufficient to consider, and the reliability of the information is also very vital. To overcome these flaws, this paper presented a new method for solving the fully fuzzy DEA model where all parameters are Z-numbers. The new approach is primarily based on crisp linear programming and has a simple structure. Moreover, it is proved that the only existing method to solve FFDEA with Z-numbers is not valid. An example is also presented to illustrate the efficiency of our proposed method and provide an explanation for the content of the paper.


1997 ◽  
Vol 119 (2) ◽  
pp. 293-298 ◽  
Author(s):  
Salem A. K. Al-Assadi

In this paper, we provide an alternative method for solving the more general servomechanism problem. The new approach based on designing a simple structure of a dynamic output feedback controller to achieve asymptotic tracking, disturbance rejection and pole assignment in linear time-invariant multivariable control systems. In addition, the resulting dynamic compensator is robust in the sense that asymptotic regulation take place for some or all disturbances and reference signals independent of any nondestabilizing perturbations in the system parameters. The main results of this paper are illustrated by an example.


1999 ◽  
Vol 173 ◽  
pp. 185-188
Author(s):  
Gy. Szabó ◽  
K. Sárneczky ◽  
L.L. Kiss

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.


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