State Of Chaos Research Articles

Jerky flow model as a basis for research in deformation instabilities

A phenomenological jerky flow model was developed in which macroscale plastic strain rates are defined by dislocation kinetics. The model takes into account destructive processes governed by shear and bulk defect accumulation. At the heart of the model lie equations of solid mechanics and relaxation-type constitutive equations. A loaded elastoplastic solid is treated as a nonlinear dynamic system whose evolution, according to synergetic laws, is much contributed by negative and positive feedbacks expressed, respectively, through constitutive equations of the first group (relaxation equations) and constitutive equations of the second group (kinetic equations for deformation defect and damage accumulation rates). The negative feedback stabilizes deformation by relaxation, bringing the process to some local dynamic equilibrium. The positive feedback destabilizes deformation, driving the system to a critical state. Numerical experiment was performed in 2D and 3D statements. Statistical analysis of stress fluctuations about the average trend shows that the jerky flow model of an elastoplastic medium demonstrates evolution characteristic of nonlinear dynamic systems: through states of dynamic chaos and self-organized criticality to a global catastrophe.

B-Z化学振荡反应在分析检测中的应用

简单介绍了经典B-Z化学振荡体系，综述了化学振荡的各种行为，规则振荡、混沌、分叉在分析检测中的应用，展望了应用前景。 A brief introduction has been made for classical B-Z oscillation chemical reaction. The application of regular oscillation, chaos, and non-equilibrium stationary state in analytical determination was described. Finally, the prospec- tives of oscillation chemical reaction research and application are prospected.

Experimental study on chaos generation in an all-fiber erbium-doped fiber ring laser with a Mach-Zehnder interferometer

We experimentally study the chaotic behaviors in a compact all-fiber erbium-doped fiber ring laser (ED-FRL) with an added Mach-Zehnder interferometer (MZI) by using a phase-modulation method. A piezo-electric ceramic transducer (PZT) is incorporated in the MZI to introduce single-frequency phase modulation. The coexistence of intermittency and period-doubling bifurcation routes to chaos in the EDFRL system is observed by adjusting the modulation frequency or the phase modulation depth in the experiment. In addition, the EDFRL presents irregular multi-longitudinal-mode oscillation with a definite linear polarization when operating at intensity chaos state.

Transforming a Dumping Site Into a Psychiatric Inpatient Unit in Somalia

Back to table of contents Previous article Next article PerspectivesFull AccessTransforming a Dumping Site Into a Psychiatric Inpatient Unit in SomaliaJibril Handuleh, M.B.B.S.Jibril HandulehSearch for more papers by this author, M.B.B.S.Published Online:1 Nov 2013https://doi.org/10.1176/appi.ajp.2013.13010044AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail Above: The new psychiatric unit at the hospital in Borama, Somalia. Left: The doctors and nurses having clinical case discussions after rounds.Somalia is a country in the horn of Africa in a region known for wars, hunger, and droughts. The country has been in a state of chaos since 1991, when the last serving dictator, Siad Barre, was overthrown. According to the World Health Organization, two out of every five people in the country suffer from mental health disorders (1). Qat, or khat, a stimulant containing an amphetamine-like substance, makes the situation worse and is sometimes associated with psychosis (2). Since 2000, British institutions, including King's College London and the charity Tropical Health and Education Trust, have been helping the local Somali people to develop their own services through education of doctors (3). Local graduating health professionals have been given short courses in psychiatry and, through online tutorials, helped from a distance to develop mental health services in Somalia (4, 5).The images shown here come from Borama, a town in northwestern Somalia. Borama has a population of 150,000 and is home to Amoud University Medical School. The local community decided to fund a psychiatric inpatient unit in Borama Hospital, to reduce stigma by integrating psychiatry into the hospital. The Somali diaspora communities in northern Europe, with the backing of the local community leaders, raised enough money to build an inpatient psychiatric unit in Borama Hospital with no international support.The psychiatric unit was built on a former hospital dumping site. Construction began in February 2012, and the unit opened its doors in June 2012. It has 24 beds and an outpatient department.From the Amoud School of Health Sciences, Borama, Somalia.Address correspondence to Dr. Handuleh (jibriil.[email protected]com).Photographs provided by Dr. Handuleh and approved by Borama Hospital and the community. The author thanks everyone who contributes to the services of the unit.References1 World Health Organization: A Situation Analysis of Mental Health in Somalia. http://applications.emro.who.int/dsaf/EMROPUB_2010_EN_736.pdfGoogle Scholar2 Odenwald M, Neuner F, Schauer M, Elbert T, Catani C, Lingenfelder B, Hinkel H, Häfner H, Rockstroh B: Khat use as risk factor for psychotic disorders: a cross-sectional and case-control study in Somalia. BMC Med 2005; 3:5Crossref, Medline, Google Scholar3 Leather A, Ismail EA, Ali R, Abdi YA, Abby MH, Gulaid SA, Walhad SA, Guleid S, Ervine IM, Lowe-Lauri M, Parker M, Adams S, Datema M, Parry E: Working together to rebuild health care in post-conflict Somaliland. Lancet 2006; 368:1119–1125Crossref, Medline, Google Scholar4 Finlayson AE, Baraco A, Cronin N, Johnson O, Little S, Nuur A, Tanasie D, Leather A: An international, case-based, distance-learning collaboration between the UK and Somaliland using a real-time clinical education website. J Telemed Telecare 2010; 16:181–184Crossref, Medline, Google Scholar5 Syed Sheriff R, Whitwell S: An innovative approach to integrating mental health into health systems: strengthening activities in Somaliland. Intervention 2012; 10:59–65Crossref, Google Scholar FiguresReferencesCited byDetailsCited ByHigh variability of the current mental health practices around the globe: Twenty days in the lives of psychiatrists and other mental health care professionals from all over the world18 September 2020 | Global Psychiatry, Vol. 0, No. 0 Volume 170Issue 11 November 2013Pages 1248-1248 Metrics PDF download History Accepted 1 February 2013 Published online 1 November 2013 Published in print 1 November 2013

A mathematical exploration into manipulation and control of a bifurcative dreaming process

Mathematical models derived from the concepts of nonlinear dynamics and chaos theory for representing the highly nonrational transformations and bifurcations in a dreaming process may be highly useful for the study of dreams. In this work, three chaotic dynamical models known as the logistic map, sine map and cubic map have been adopted as a mathematical analogy for representing bifurcative dreaming processes. Further, the effect of a dream potentiator has been incorporated into the adopted models. For studying the effects of the dream potentiator on the actual dreaming process, computer simulations were performed. Results demonstrate that the dream potentiator may enhance the actual dream by elevating the dream states, by expanding the bifurcations and by reducing the number of successive steps required for attaining a dream state of deterministic chaos.

Dynamical characteristics and their applications of semiconductor lasers subject to both optical injection and optical feedback.

We experimentally investigate the dynamical characteristics of semiconductor lasers subject to both the optical injection (OI) and the optical feedback (OF). By coupling the OI and the OF lights into the same fiber before injecting into the slave laser (SL), the ratio between the two perturbations can be accurately determined and controlled. The frequency shifts in the cavity resonance frequency of the SL (νSL) induced by the OI and the OF lights are compared quantitatively. To study the competition between the OI and the OF in the SL, the mapping of the dynamical scenarios and states are plotted in the parameter space. This mapping serves as the guideline for choosing the appropriate operation conditions in various applications employing both the OI and the OF at the same time. In this paper, the suitable feedback strengths to narrow the linewidths of photonic microwave signals generated by the OI are studied. The limitation of using OI in enhancing the bandwidths of the chaos states generated by the OF is discussed. Moreover, to suppress the unwanted dynamics due to the feedback, the optimal injection parameters of the OI are shown.

Chaos in Family Law: A Model for the Recognition of Intimate Relationships in South Africa

The chaos theory is utilised in a metaphorical manner to describe the current state of family law and more specifically law regulating intimate relationships in South Africa. A bird's eye view of the law of intimate relationships is provided to indicate that the current system of law regulating intimate relationships is in a state of chaos. Deregulation of intimate relationships and regulation by contract as well as a singular Act regulating intimate relationships are investigated as alternatives to the current system. The paper concludes that deregulation does not pose a viable alternative model to recognise intimate relationships. The ideal will be to have a singular Act regulating all intimate relationships. The conclusion and termination of these relationships should be less formal than the current system. The parties should be free to regulate the consequences of their intimate relationship by a relationship contract. Default contracts should be contained in the Act to ensure substantive equality in intimate relationships.Keywords: Chaos; Legal pluralism; Intimate relationships; Civil marriage; Civil union; Religious marriage; Domestic partnerships; Relationship contracts; Marriage Act 25 of 1961; Recognition of Customary Marriages Act 120 of 1998, Civil Union Act 17 of 2006; Domestic Partnership Bill

Chaotic Characteristic Analysis of Concrete Fracture System Based on Lyapunov Exponent Stability Criterion

According to the research on whole curves of strain-stress of concrete materials, the paper illustrates in evidence features of stages and shows that the discrete feature of curve often occurs in strain-softening stage. After chaotic dynamic analysis of testing datas, it presents that system of whole process of strain-stress evolves from ordered steady state to low chaotic state and then to high chaotic state along with increase of compressive strength. The linear relationship of strain-stress grows evident and the system evolves from strong ordered steady state to low chaos state. The strain-stress system before compressive strength peak is basically in weak chaotic state. Theis proposed to be the stability criterion of concrete features in different stress stages, and the is regarded as the representative value of the system stability degree. The calculation of example shows that the stability criterion definited by the proposed method is consistent with the actural situation.

Phase locking route behind complex periodic windows in a forced oscillator

Chaotic systems have complex reactions against an external driving force; even in cases with low-dimension oscillators, the routes to synchronization are diverse. We proposed a stroboscope-based method for analyzing driven chaotic systems in their phase space. According to two statistic quantities generated from time series, we could realize the system state and the driving behavior simultaneously. We demonstrated our method in a driven bi-stable system, which showed complex period windows under a proper driving force. With increasing periodic driving force, a route from interior periodic oscillation to phase synchronization through the chaos state could be found. Periodic windows could also be identified and the circumstances under which they occurred distinguished. Statistical results were supported by conditional Lyapunov exponent analysis to show the power in analyzing the unknown time series.

Comparisons of typical nonlinear states in single- and dual-beam optically injected semiconductor lasers

The characteristics of the typical nonlinear states in an optically injected laser system with single- and dual-beam injection are analyzed and compared numerically. Both single- and dual-beam optical injection systems can generate periodic oscillations and chaos states but with different characteristics. By observing the evolution process of periodic oscillations, it is found that dual-beam injection induced periodic oscillations have multiple time series patterns including continuous periodic signals with single peak (CPS) and continuous periodic signals with subharmonic (CPSSH), while for single-beam injection with either of the dual-beam injection parameters generated periodic oscillations, the extremum numbers of the time series equal to the frequency period numbers of the optical spectrum. In addition, the great advantages of bandwidth enhancement effect for chaos oscillations are obtained by using dual-beam injection. Furthermore, extensive numerical simulations reveal that dual-beam injection system undergoes period-doubling routes to chaos, which is identical to that in single-beam injection system. Finally, the characteristics of newly clustered NDFWM dynamics in dual-beam injection system are analyzed.

The everyday life of adult family members of working aged survivors of stroke during the first year after the stroke – an integrative review

The purpose of this integrative review was to describe the everyday life of adult family members of working aged survivors of stroke during the first year after the occurrence of the stroke. The studies were researched from Medline, Cinahl, PsycINFO, Medic and Linda databases. The data consisted of 40 articles which were published in scientific journals during 2007-2012. The quality of the articles were assessed with the critical appraisal tools JBI QARI and JBI MAStARI [1] . The articles were analyzed with thematic analysis. The everyday life of adult family members included initially becoming the family member of a survivor of stroke, living as their family member, and eventually coming to terms with life with the survivor of a stroke . Becoming the family member meant living in a focused state of chaos, trying to be strong for the loved one, and going forward in life. It also emphasized the need to rebuild and find a balance in the shadow of the illness and the needs of this complex situation. Coming to terms with the changed life situation of the family member consisted of trying to stabilize emotional wellbeing amid bouts of anxiety and depression. The results of this research should help nurses to better meet the needs of family members at the right time in order to help them deal with expected problems. There is much evidence about older caregivers’ needs, but only scant evidence about younger caregivers and their working aged relatives, especially just after the stroke. This integrative literature review gives important information about the everyday life of family members of working aged survivors of stroke and helps nurses to better understand them and their needs.

The Chaos State of Internet and Coping Method

The Chaos State of Internet and Coping Method

Rapid iterative incremental model of the intermittent chaos of deep hole developing in coal-gas outburst

In view of the occurrence of the coal and gas, outburst coal body separates in series of layer form, and tosses in a series of coal shell, and the morphological characteristics of the holes that formed in the coal layers are very similar to some iterative morphological characteristics of the system state under highly nonlinear condition in chaos theory. Two kinds of morphology as well as their starting and end states are comparatively studied in this paper. The research results indicate that the outburst coal and rock system is in a chaotic state of lower nested hierarchy before outburst, and the process that lots of holes form owing to continuous outburst of a series of coal shells in a short time is in a rhythmical fast iterative stage of intermittent chaos state. And the state of the coal-gas system is in a stable equilibrium state after outburst. The behaviors of outburst occurrence, development and termination, based on the universal properties of various nonlinear mappings in describing complex problems, can be described by iterative operation in mathematics which uses the Logistic function f(x,μ)=μx(1-x) and the composite function F(3, x)=f(3)(x, μ) as kernel function. The primary equation of relative hole depth x and outburst parameter μ in kernel function are given in this paper. The given results can deepen and enrich the understanding of physical essence of outburst.

Chaotic operation and chaos control of travelling wave ultrasonic motor

The travelling wave ultrasonic motor, which is a nonlinear dynamic system, has complex chaotic phenomenon with some certain choices of system parameters and external inputs, and its chaotic characteristics have not been studied until now. In this paper, the preliminary study of the chaos phenomenon in ultrasonic motor driving system has been done. The experiment of speed closed-loop control is designed to obtain several groups of time sampling data sequence of the amplitude of driving voltage, and phase-space reconstruction is used to analyze the chaos characteristics of these time sequences. The largest Lyapunov index is calculated and the result is positive, which shows that the travelling wave ultrasonic motor has chaotic characteristics in a certain working condition Then, the nonlinear characteristics of travelling wave ultrasonic motor are analyzed which includes Lyapunov exponent map, the bifurcation diagram and the locus of voltage relative to speed based on the nonlinear chaos model of a travelling wave ultrasonic motor. After that, two kinds of adaptive delay feedback controllers are designed in this paper to control and suppress chaos in USM speed control system. Simulation results show that the method can control unstable periodic orbits, suppress chaos in USM control system. Proportion-delayed feedback controller was designed following and arithmetic of fuzzy logic was used to adaptively adjust the delay time online. Simulation results show that this method could fast and effectively change the chaos movement into periodic or fixed-point movement and make the system enter into stable state from chaos state. Finally the chaos behavior was controlled.

USA Trends (9) “Japanese Ways vs. American Ways in Revival from Recent State of Chaos”

USA Trends (9) “Japanese Ways vs. American Ways in Revival from Recent State of Chaos”

Adaptive Control of Rotor-bearing System with Coupling Faults of Pedestal Looseness and Rub-impact

Pedestal looseness and rub-impact are two important faults in rotating machinery. Once the Pedestal looseness is developed in a rotor system, the rotor is more likely to make contact with stator under tight clearance conditions. Due to the presence of both Pedestal looseness and rub-impact, the whole system becomes highly nonlinear and instability. The present study is aimed to simulate a chaotic system of the nonlinear rotor system and the system can adaptively be converted to normal working state under the circumstance of the chaotic state occasioned by outside perturbation for the complicated chaotic system. The nonlinear dynamic equations of rotor-bearing system with coupling faults of pedestal looseness and rub-impact force are derived and a multi-parameter adaptive control algorithm is given. As a result, it is found that those systems possess various nonlinear dynamical inherences. The numerical results also show that the parametric adaptive control method is appropriate to those rotor-bearing systems, outside interference under the state of chaos arising from the situation can be adaptive to adjust to normal working condition. It has strongly control capability of stability. The theoretical and practical idea for controlling rotor–bearing systems and optimizing their operation can be more precise.

Evolution of spiral waves in indirectly coupled excitable medium with time-delayed coupling

The interaction between two spiral waves in two-layer excitable medium coupled indirectly through a passive medium and with time-delayed coupling is investigated by using the Bär model. The numerical results show that time-delayed coupling can either facilitate the synchronization of two spiral waves or lead to the transition from spiral wave to collective oscillation, different target waves, spatiotemporal chaos or rest state. Period-2 and period-3 spiral waves and the meander or drift of spiral wave are observed in the coupled excitable medium. The physical mechanism underlying these phenomena is discussed.

Price game and chaos control among three oligarchs with different rationalities in property insurance market

Combining with the actual competition in Chinese property insurance market and assuming that the property insurance companies take the marginal utility maximization as the basis of decision-making when they play price games, we first established the price game model with three oligarchs who have different rationalities. Then, we discussed the existence and stability of equilibrium points. Third, we studied the theoretical value of Lyapunov exponent at Nash equilibrium point and its change process with the main parameters' changes though having numerical simulation for the system such as the bifurcation, chaos attractors, and so on. Finally, we analyzed the influences which the changes of different parameters have on the profits and utilities of oligarchs and their corresponding competition advantage. Based on this, we used the variable feedback control method to control the chaos of the system and stabilized the chaos state to Nash equilibrium point again. The results have significant theoretical and practical application value.

The research on price game model and its complex characteristics of triopoly in different decision-making rule

Based on a detailed analysis of the international market, we establish a decentralized dynamics model to describe the situation that a new oligarch wishes to enter into a market which has been occupied by two oligarchs, so they have different decision rules. Then we establish and analyze the corresponding continuity system, and in detail discuss the Lyapunov exponent of this system, studying the influence of the parameter’s change to the Lyapunov exponent in three situations. Proceeding to the next step, we make the analysis of the complex dynamics behavior, such as Hopf bifurcation, chaos attractor and initial sensibility. We make a numerical simulation under different conditions, and the result shows that the process of game will tend to a Nash equilibrium at a lower price adjustment speed, and with the increase of the value, the system will appear to be unstable and go into a chaos state gradually. However, for the new entrant, the influence of chaos is not huge, and the new entrant can be seen as a stable element in the chaotic market. The research leads to a good guidance to the market with a new entrant to do the best decision-making.

Experimental investigation on chaos generation in erbium-doped fiber single-ring lasers

In this paper, the chaotic behaviors in an erbium-doped fiber (EDF) single-ring laser (EDFSRL) are investigated experimentally by using the loss modulation method. An electro—optic modulator (EOM) made of LiNbO3 crystal is added to the system. Thus, by changing the modulation voltage and the modulation frequency of the EOM, the freedom of the EDFSRL system is increased. The chaotic characteristics of the system are studied by observing the time series and the power spectra. The experimental results indicate that the erbium-doped fiber single-ring laser system can enter into chaos states through period-doubling bifurcation and intermittency routes.