scholarly journals A mechanism for evolution of the physical concepts network

2021 ◽  
Vol 24 (2) ◽  
pp. 24001
Author(s):  
V. Palchykov ◽  
M. Krasnytska ◽  
O. Mryglod ◽  
Yu. Holovatch
Keyword(s):  
Synergistic Effect ◽  
Complex Network ◽  
Empirical Analysis ◽  
Growth Models ◽  
Underlying Mechanism ◽  
Scientific Concepts ◽  
Network Growth ◽  
Preferential Selection ◽  
Network Characteristics ◽  
Two Factors

We suggest an underlying mechanism that governs the growth of a network of concepts, a complex network that reflects the connections between different scientific concepts based on their co-occurrences in publications. To this end, we perform empirical analysis of a network of concepts based on the preprints in physics submitted to the arXiv.org. We calculate the network characteristics and show that they cannot follow as a result of several simple commonly used network growth models. In turn, we suggest that a simultaneous account of two factors, i.e., growth by blocks and preferential selection, gives an explanation of empirically observed properties of the concepts network. Moreover, the observed structure emerges as a synergistic effect of these both factors: each of them alone does not lead to a satisfactory picture.

Complex Network Theory Based Web Services Composition Benchmark Toolkit

2013 ◽  
pp. 1-22
Author(s):  
Seog-Chan Oh ◽  
Dongwon Lee
Keyword(s):  
Web Services ◽  
Complex Network ◽  
Network Theory ◽  
Ground Truth ◽  
Ai Planning ◽  
Web Services Composition ◽  
Complex Network Theory ◽  
Network Characteristics ◽  
Services Composition ◽  
Test Sets

In recent years, while many research proposals have been made toward novel algorithmic solutions of a myriad of web services composition problems, their validation has been less than satisfactory. One of the reasons for this problem is the lack of real benchmark web services data with which researchers can test and verify their proposals. In this chapter, to remedy this challenge, we present a novel benchmark toolkit, WSBen, which is capable of generating synthetic web services data with diverse scenarios and configurations using complex network theory. Web services researchers therefore can evaluate their web services discovery and composition algorithms in a more systematic fashion. The development of WSBen is inspired by our preliminary study on real-world web services crawled from the Web. The proposed WSBen can: (1) generate a collection of synthetic web services files in the WSDL format conforming to diverse complex network characteristics; (2) generate queries and ground truth sets for testing discovery and composition algorithms; (3) prepare auxiliary files to help further statistical analysis; (4) convert WSDL test sets to the formats that conventional AI planners can read; and (5) provide a graphical interface to control all these functions. To illustrate the application of the WSBen, in addition, we present case studies selected from three domains: (1) web services composition; (2) AI planning; and (3) the laws of networks in Physics community. The WSBen toolkit is available at: http://pike.psu.edu/sw/wsben/. This chapter is an invited extension of authors’ previous publication (Oh & Lee, 2009).

Loading Rate Effect on the Domain Switching of Ferroelectric Materials

2008 ◽  
Author(s):  
Ajit Achuthan ◽  
Chin-Teh Sun
Keyword(s):  
Electric Field ◽  
Loading Rate ◽  
Domain Switching ◽  
Underlying Mechanism ◽  
Ferroelectric Materials ◽  
Switching Behavior ◽  
Switching Mechanism ◽  
Two Factors ◽  
Different Characteristics ◽  
Butterfly Behavior

A method to characterize the strain electric field butterfly behavior based on the underlying domain switching mechanism is presented at first. The effect of loading rate on the different characteristics of the strain electric-field-butterfly behavior is then studied. By comparing the changes in these characteristics under different loading rates, it is established that the loading rate dependence of the strain electric field butterfly behavior is mainly due to two factors, 1) the dependence of the switching of individual domains on the magnitude and duration of the loading time and 2) the variation of the transition electric field with the loading rate. Several interesting attributes of the domain switching behavior that may shed light on understanding the underlying mechanism of domain switching further is illustrated in the present study. The present study also demonstrates that the method of characterizing the strain electric butterfly based on the underlying domain switching mechanism is very effective in studying ferroelectric behavior under different loading conditions.

scholarly journals Designing a hotel website: An empirical analysis for a classic destination using a conjoint experiment

2014 ◽  
Vol 45 (2) ◽  
pp. 51-63
Author(s):  
R. Huertas-Garcia ◽  
J. C. Gázquez-Abad ◽  
S. Forgas-Coll ◽  
A. Casas-Romeo
Keyword(s):  
Empirical Analysis ◽  
Positive Influence ◽  
Tourist Destination ◽  
Objective Information ◽  
Customer Perceptions ◽  
Factors Influencing ◽  
Two Factors ◽  
Main Factors ◽  
Conjoint Experiment

Internet has become one of the most important channels for the promotion and sale of services related to tourism. As a result, producers and distributors alike are keen to resolve the question as to which factors will determine website choice by internet browsers. In this paper we develop an experiment to determine the factors that need to be taken into consideration when designing a website for a mature, familiar tourist destination. To this end, the basic factors shaping the architecture of a website are theoretically described and, based on the results of a conjoint experiment, the main factors influencing a website for a classic destination are extracted. Our results suggest that a website that includes objective information (e.g., price, activities of interest, number of rooms) and multiple photos has a positive influence on customer perceptions. The paper also makes an important methodological contribution, as it proposes a new design for calculating the weight of the factors, interactions of two factors and the factors squared.

EMPIRICAL ANALYSIS OF BITCOIN PRICES USING THRESHOLD TIME SERIES MODELS

2018 ◽  
Vol 13 (04) ◽  
pp. 1850017
Author(s):  
RODOLFO ANGELO MAGTANGGOL III DE GUZMAN ◽  
MIKE K. P. SO
Keyword(s):  
Empirical Analysis ◽  
Threshold Model ◽  
Time Series Models ◽  
Network Characteristics ◽  
Threshold Autoregression ◽  
Block Number ◽  
Threshold Time ◽  
History Of ◽  
Threshold Time Series ◽  
The Empirical Analysis

This paper proposes the use of threshold heteroskedastic models which integrate threshold nonlinearity [Tong, H (1978). On a Threshold Model, pp. 575–586. Netherlands: Sijthoff & Noordhoff; Tong, H and KS Lim (1980). Threshold autoregression, limit cycles and cyclical data. Journal of the Royal Statistical Society. Series B (Methodological), 3, 245–292.] and GARCH-type conditional variance for modeling Bitcoin returns to provide an understanding on the huge volatility that Bitcoin has been famous for. Specifically, the model attempts to identify different regimes throughout the history of Bitcoin using the different available Bitcoin network characteristics, such as cost per transaction, number of transactions per block, number of active addresses and number of transactions. Estimation and diagnostic checks are performed using Markov chain Monte Carlo methods. In the empirical analysis, we show that our model is able to identify periods of crashes as one of these regimes, which is also a period of declining returns and declining number of active users. We also find that the number of users and the number of transactions determine the magnitude or persistence of a crash period.

An Empirical Analysis of the Eriksonian Bipolar Theory of Personality

1981 ◽  
Vol 49 (3) ◽  
pp. 819-822 ◽  
Author(s):  
Raju Varghese
Keyword(s):  
Empirical Analysis ◽  
Factor Structure ◽  
Human Personality ◽  
Two Factors ◽  
Female Subjects

Responses to an Eriksonian personality instrument by 174 female subjects were statistically analyzed to examine the factor structure of the scale and also to consider whether the results are consistent with earlier findings. The two factors derived, termed retrogression and actualization, seemed to support the bipolar nature of the instrument and to be consistent with the two basic dimensions of human personality suggested by Erikson.

scholarly journals A SIMPLE SOLID-ON-SOLID MODEL OF EPITAXIAL FILM GROWTH: SURFACE ROUGHNESS AND DYNAMICS

1999 ◽  
Vol 10 (04) ◽  
pp. 645-657 ◽  
Author(s):  
K. MALARZ ◽  
A. Z. MAKSYMOWICZ
Keyword(s):  
Surface Roughness ◽  
Film Growth ◽  
Growth Models ◽  
Limited Range ◽  
Growth Exponent ◽  
Growth Surface ◽  
Model Calculations ◽  
Surface Migration ◽  
Two Factors ◽  
Epitaxial Film Growth

The random deposition model must be enhanced to reflect the variety of surface roughness due to some material characteristics of the film growing by vacuum deposition or sputtering. The essence of the computer simulation in this case is to account for possible surface migration of atoms just after the deposition, in connection with the binding energy between atoms (as the mechanism provoking the diffusion) and/or diffusion energy barrier. The interplay of these two factors leads to different morphologies of the growing surfaces, from flat and smooth ones to rough and spiky ones. In this paper, we extended our earlier calculation by applying an extra diffusion barrier at the edges of terrace-like structures, known as the Ehrlich–Schwoebel barrier. It is experimentally observed that atoms avoid descending when the terrace edge is approached, and these barriers mimic this tendency. Results of our Monte Carlo computer simulations are discussed in terms of surface roughness, and compared with other model calculations and some experiments from literature. The power law of the surface roughness σ against film thickness t was confirmed. The nonzero minimum value of the growth exponent β near 0.2 was obtained which is due to the limited range of the surface diffusion and the Ehrlich–Schwoebel barrier. Observations for different diffusion ranges are also discussed. The results are also confirimed with some deterministic growth models.

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