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Article

Kostas Karamanos, Ioannis Mistakidis and Simeon Mistakidis

The purpose of this paper is to illustrate the many aspects of Poincare recurrence time theorem for an archetype of a complex system, the logistic map.

Abstract

Purpose

The purpose of this paper is to illustrate the many aspects of Poincare recurrence time theorem for an archetype of a complex system, the logistic map.

Design/methodology/approach

At the beginning of the twentieth century, Poincare's recurrence theorem had revolutionized modern mechanics and statistical physics. However, this theorem did not attract considerable attention, at least from a numerical and computational point of view. In a series of relatively recent papers, Balakrishnan, Nicolis and Nicolis have addressed the recurrence time problem in a firm basis, introducing notation, theory, and numerical studies. Motivated by this call, the paper proposes to illustrate the many aspects of Poincare recurrence time theorem for an archetype of a complex system, the logistic map. The authors propose here in different tests and computations, each one illuminating the many aspects of the problem of recurrence. The paper ends up with a short discussion and conclusions.

Findings

In this paper, the authors obtain new results on computations, each one illuminating the many aspects of the problem of recurrence. One striking aspect of this detailed work, is that when the sizes of the cells in the phase space became considerable, then the recurrence times assume ordinary values.

Originality/value

The paper extends previous results on chaotic maps to the logistic map, enhancing comprehension, making possible connections with number theory, combinatorics and cryptography.

Content available
Article

Lisa Crona and Louise Brådvik

This study is a follow-up of inpatients diagnosed with severe depression/melancholia between 1956 and 1969. During this period, all inpatients at the Department of…

Abstract

This study is a follow-up of inpatients diagnosed with severe depression/melancholia between 1956 and 1969. During this period, all inpatients at the Department of Psychiatry, University Hospital, Lund, were rated on a multidimensional diagnostic schedule on discharge. There were 471 patients born from 1920 onward. In the present follow-up, 2006 to 2010, 169 survivors could be traced. They were asked to participate in the study involving a telephone interview, in which a structured life chart was used. Of the patients contacted, 16 were ill or confused and 3 did not remember ever being depressed, leaving 150 who could participate. Seventy-five of these agreed to participate in the study. Long-term course of depression was evaluated by cluster analysis and compared to background variables, such as heredity for depression, perceived parental rearing behaviour, and treatment of index depressive episode. Using a cluster analysis the patients could be separated into six clusters describing the course: i) single or few episodes followed by long-lasting remission; ii) single or few episodes followed by long-lasting remission, although shorter; iii) single or few episodes followed by late recurrence; iv) single or few episodes, but more frequently ill, followed by late recurrence; v) several episodes followed by lasting remission; vi) chronic course of episodes. Remission or recurrence could therefore occur even after more than a decade. In summary, there was a short-term course with or without recurrence or a chronic course with or without late remission. Heredity for depression was significantly related to a chronic course with or without late remission.

Details

Mental Illness, vol. 4 no. 2
Type: Research Article
ISSN: 2036-7465

Keywords

Content available
Article

Som Mungmonphoncharoen, Tawatchai Apidechkul and Pannipha Dokmaingam

The purpose of this paper is to determine the factors associated with DF occurrence in recurrence villages in Chiang Rai, Thailand.

Abstract

Purpose

The purpose of this paper is to determine the factors associated with DF occurrence in recurrence villages in Chiang Rai, Thailand.

Design/methodology/approach

A case-control study was conducted between June 2017 and December 2017. A validated questionnaire was used to detect the factors associated with recurrence of DF. χ2 and logistic regression were used to detect the associations between variables at α=0.05.

Findings

In total, 213 cases and 436 controls were recruited into the analysis. Cases were recruited from 20 DF recurring villages, while controls were recruited from 20 non-DF recurring villages in Chiang Rai province. At community level, three variables were associated with recurrence of DF; size of the village (p=0.007), number of villagers (p=0.009), tribe (p=0.043) and distance to a hospital (p=0.003). Three variables were associated with DF at personal and family levels in multivariate model: children whose parents worked as daily employees, and government officers and traders were more likely to have DF 1.56 (95%CI=1.22–2.48) and 4.31 (95%CI=4.66–9.38) times greater than of those whose parents’ worked as agriculturists, respectively; children aged less than one year were 2.89 (95%CI=2.17–4.33) times more likely to have DF than those aged=6 and children who were under standard growth and over standard growth were more likely to have DF than those standard growth 1.61 (95%CI=1.18–2.53) and 7.33 (95%CI=4.39–10.37) times, respectively.

Originality/value

This is the original research article which was conducted in detecting the factors associated with recurrence of DHF in Northern Thailand.

Details

Journal of Health Research, vol. 33 no. 6
Type: Research Article
ISSN: 2586-940X

Keywords

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Article

Guodong Sun, Hua Zhu and Cong Ding

AISI 52100-AISI 1045 specimens were used as the ring-on-disc tribopairs in the experiments to investigate the stability of friction process.

Abstract

Purpose

AISI 52100-AISI 1045 specimens were used as the ring-on-disc tribopairs in the experiments to investigate the stability of friction process.

Design/methodology/approach

The coefficient of friction (COF) signals were measured throughout the friction process and the recurrence plots (RPs) and recurrence quantification analysis (RQA) are adapted to analyze the stability of the tribosystem.

Findings

The results show that the COF time-series acquired from different tests possess the same dynamic evolution laws. The evolution of RPs follows the rules of “disrupted-homogeneous-disrupted,” which corresponds to the “running-in, steady-state and increasing stages” of friction process. Additionally, the evolution laws of RQA measures LAM, Vmax and TT accord with the “bathtub curve.” Therefore, both RPs and RQA measures can inform quantitative interpretations of tribological behaviors and friction process identification.

Originality/value

The both RPs and RQA are capable of characterizing the tribological behaviors and can depict the various stages of friction process.

Details

Industrial Lubrication and Tribology, vol. 71 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

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Article

Hector Sabelli and Lazar Kovacevic

The purpose of this paper is to examine the possibility of biotic patterns. In economics, markets are thought to tend to equilibrium with random and unpredictable…

Abstract

Purpose

The purpose of this paper is to examine the possibility of biotic patterns. In economics, markets are thought to tend to equilibrium with random and unpredictable deviations. However, an explosion of empirical work searching for possible chaos show an enormous amount of unexplained nonlinear structure. These observations led the authors to examine the possibility of biotic patterns in economics.

Design/methodology/approach

Bios is defined as a causally generated creative process. It is the causal counterpart to random walk, just as chaos is the causal equivalent to randomness. Economic data consisting of time series from several categories, including banking, employment and population, and gross domestic product and components, were studied for diversification, recurrence, and predictability patterns characteristic of bios. Diversification was quantified as increased variance with embedding, recurrences were measured using newly developed computer programs, and predictability was measured with a nonlinear prediction method.

Findings

Dynamic analyses of the data show: episodic patterning and asymmetric statistical distribution, typical of bios; increase in variance with embedding (diversification), less recurrence than shuffled copies of the data (novelty), demonstrating creativity; consecutive recurrence; and patterning in the series of differences, indicating non‐random causation.

Originality/value

The demonstration of bios in empirical data indicates that the economy is non‐stationary, causal, and creative. This contradicts the notion that markets regulate themselves and tend to equilibrium, and the characterization of market variation as random or chaotic. Further economic crises may be avoided by acknowledging that financial markets are not bound within limits and can be modified into new forms by human action.

Details

Kybernetes, vol. 40 no. 1/2
Type: Research Article
ISSN: 0368-492X

Keywords

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Book part

Kousik Guhathakurta, Basabi Bhattacharya and A. Roy Chowdhury

It has long been challenged that the distributions of empirical returns do not follow the log-normal distribution upon which many celebrated results of finance are based…

Abstract

It has long been challenged that the distributions of empirical returns do not follow the log-normal distribution upon which many celebrated results of finance are based including the Black–Scholes Option-Pricing model. Borland (2002) succeeds in obtaining alternate closed form solutions for European options based on Tsallis distribution, which allow for statistical feedback as a model of the underlying stock returns. Motivated by this, we simulate two distinct time series based on initial data from NIFTY daily close values, one based on the Gaussian return distribution and the other on non-Gaussian distribution. Using techniques of non-linear dynamics, we examine the underlying dynamic characteristics of both the simulated time series and compare them with the characteristics of actual data. Our findings give a definite edge to the non-Gaussian model over the Gaussian one.

Details

The Spread of Financial Sophistication through Emerging Markets Worldwide
Type: Book
ISBN: 978-1-78635-155-5

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Article

Zhivko Georgiev and Ivan Trushev

This paper aims to analyze transient and steady state processes in series resistive capacitive-circuits when the supplied voltage is a sequence of periodic rectangular…

Abstract

Purpose

This paper aims to analyze transient and steady state processes in series resistive capacitive-circuits when the supplied voltage is a sequence of periodic rectangular pulses. The purpose is to obtain an analytical formula for the capacitor voltage at any instant of time, both for the transient and the steady-state processes.

Design/methodology/approach

The main approach is to use a combination of differential and recurrence equations.

Findings

An analytical expression (formula) for obtaining the capacitor voltage at any instant of time has been found.

Originality/value

The results obtained are new. They are much more convenient to use than the results obtained by the Fourier series. The exposed approach can also be used in other circuits and other forms of the supplied voltage.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0332-1649

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Book part

Daniele Besomi

Business cycle theory is normally described as having evolved out of a previous tradition of writers focusing exclusively on crises. In this account, the turning point is…

Abstract

Business cycle theory is normally described as having evolved out of a previous tradition of writers focusing exclusively on crises. In this account, the turning point is seen as residing in Clément Juglar's contribution on commercial crises and their periodicity. It is well known that the champion of this view is Schumpeter, who propagated it on several occasions. The same author, however, pointed to a number of other writers who, before and at the same time as Juglar, stressed one or another of the aspects for which Juglar is credited primacy, including the recognition of periodicity and the identification of endogenous elements enabling the recognition of crises as a self-generating phenomenon. There is indeed a vast literature, both primary and secondary, relating to the debates on crises and fluctuations around the middle of the nineteenth century, from which it is apparent that Juglar's book Des Crises Commerciales et de leur Retour Périodique en France, en Angleterre et aux États-Unis (originally published in 1862 and very much revised and enlarged in 1889) did not come out of the blue but was one of the products of an intellectual climate inducing the thinking of crises not as unrelated events but as part of a more complex phenomenon consisting of recurring crises related to the development of the commercial world – an interpretation corroborated by the almost regular occurrence of crises at about 10-year intervals.

Details

A Research Annual
Type: Book
ISBN: 978-0-85724-060-6

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Article

Peter Bliss, Peter A. Trott and Peter R. Blake

Objectives: The cost‐effectiveness of routine cervical cytology during follow‐up after treatment for carcinoma of cervix is examined. Subjects: All patients having routine…

Abstract

Objectives: The cost‐effectiveness of routine cervical cytology during follow‐up after treatment for carcinoma of cervix is examined. Subjects: All patients having routine follow‐up smears during the financial year 1993–1994. A total of 212 patients generated 311 smears, 96 had an intact cervix and 116 had surgical removal as part of their treatment. Ninety‐one patients with intact cervices and 109 without were evaluable. Results: Nine recurrences were detected, in every case this was expected, based on clinical findings. In two of these the smear was reported as normal. Two hundred and thirty smears were from entirely asymptomatic patients. Conclusions: Limiting cervical smears to those who are symptomatic, or where an abnormality is found on examination, would save approximately £3500 per year. This cost needs to be set beside the possibility of detecting an asymptomatic recurrence at an early stage; as reported by others. This suggests that the impact of this strategy is limited. A randomized trial with prospective economic assessment would be the only way to evaluate the cost‐effectiveness of routine cervical smears in the follow‐up of patients treated for cancer of cervix.

Details

Journal of Clinical Effectiveness, vol. 2 no. 3
Type: Research Article
ISSN: 1361-5874

Content available
Book part

Yopie Afriandi Habibie and Dudy Hanafy

Purpose – Intravenous leiomyomatosis (IVL) is a very rare subtype of leiomyoma, involving the right obstruction of the heart, and is an unusual cause of outflow tract…

Abstract

Purpose – Intravenous leiomyomatosis (IVL) is a very rare subtype of leiomyoma, involving the right obstruction of the heart, and is an unusual cause of outflow tract obstruction. The IVL grows from the vessel’s smooth muscle, protruding into the vessel’s lumen, and can expand to the right atrium and even beyond causing death due to blood flow obstruction into the right atrium and even to pulmonary artery.

Design/Methodology/Approach – We present a 33-year-old Indonesian woman with cardiopulmonary symptoms predominantly, and marked by an intravascular leiomyoma extending from inferior vena cava (IVC) to right chamber atrium, with the chief complaint being easily fatigued since seven months.

Findings – Echocardiography observations found a mass in the right atrium and the IVC that caused dynamics obstructed in tricuspid valve, right atrium and ventricle were dilated, no left ventricular (LV) hypertrophy, normal LV and right ventricular (RV) functions, and no valve abnormality except the tricuspid valve gradient being 21 mmHg with mild regurgitation. Venography resulted in a mobile tumor mass in IVC mouth which partially flew into the right atrium, and partially blocked the IVC mouth. Tumor size was 6.4 cm × 4.8 cm. Abdominal multislice computed tomography resulted in a residual soft tissue mass (leiomyoma) along the IVC extended to the right atrium. The tumor mass size in the IVC and the right atrium was bigger compared to tumor mass on July 2008. The correct diagnosis was established during surgery; therefore a two-stage resection was done.

Originality/Value – Surgical resection is the best treatment for intracardiac extension of intravenous leiomyoma. To remove the ilio-caval portion, iliac venotomy was recommended for the tumor in both stages of the surgeries.

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