On the Characteristics of Bifurcation and Nonlinear Dynamic Response

2004 ◽  
Vol 126 (4) ◽  
pp. 574-579 ◽  
Author(s):  
Baozhong Yang ◽  
C. Steve Suh

Spectral analysis has been widely applied to the detection of bifurcation and the determination of the extent to which dynamic instability and chaotic responses develop. However, because spectral analysis employs stationary sinusoids in representing time-varying signals of inherent nonlinearity, the use of Fourier domain methodologies would inexorably risk misinterpreting the true characteristics and obscuring the underlying physics of the nonlinear system being investigated. The fact that the amplitude and frequency of all the individual spectral component of a nonlinear, nonstationary dynamic response are modulated and coupled in time necessarily implies that, if the inception and transition of a bifurcated state of unstable motion is to be fully characterized, amplitude modulation and frequency modulation need to be temporally decoupled. The fundamental notion of instantaneous frequency defines frequency as the temporal gradient of phase and thus provides a powerful mechanism through which amplitude modulation and frequency modulation can be disassociated. Results of applying instantaneous frequency to the characterization of bifurcation and evolution of instability for a cracked rotor also indicate that instantaneous frequency interprets nonlinear rotary responses with sound physical bases.

1981 ◽  
Vol 35 (5) ◽  
pp. 475-485 ◽  
Author(s):  
Paul C. Painter ◽  
Randy W. Snyder ◽  
Michael Starsinic ◽  
Michael M. Coleman ◽  
Deborah W. Kuehn ◽  
...  

The problems associated with the application of FT-IR to the characterization of coal structure are critically discussed. The controversies concerning band assignments are considered and it is concluded that the strong 1600 cm−1 band can be assigned to an aromatic ring stretching mode that in most coals is intensity enhanced by the presence of phenolic groups. The application of computer routines to the determination of OH and CH groups is considered. Established criteria for curve fitting are applied to the problem. Qualitative identification of functional groups is achieved, but consistent quantitative measurements will require a determination of the relationship between the extinction coefficients of resolved bands.


2020 ◽  
Vol 49 (3) ◽  
pp. 690-696
Author(s):  
Kiyoko Takamura ◽  
Takatoshi Matsumoto

Titanium(iv)–4-(2-pyridylazo)resorcinol (Ti–PAR) has been effectively used for the determination of hydrogen peroxide.


2013 ◽  
Vol 33 (5) ◽  
pp. 0530002 ◽  
Author(s):  
付小芳 Fu Xiaofang ◽  
马维光 Ma Weiguang ◽  
谭巍 Tan Wei ◽  
赵刚 Zhao Gang ◽  
李志新 Li Zhixin ◽  
...  

2020 ◽  
Vol 11 (1) ◽  
pp. 93-99
Author(s):  
Abu Zakir Morshed ◽  
Sheikh Shakib ◽  
Tanzim Jahin

Corrosion of reinforcement is an important durability concern for the structures exposed to coastal regions. Since corrosion of reinforcement involves long periods of time, impressed current technique is usually used to accelerate the corrosion of reinforcement in laboratories. Characterization of impressed current technique was the main focus of this research,which involved determination of optimum chloride content and minimum immersion time of specimens for which the application of Faraday’s law could be efficient. To obtain optimum chloride content, the electrolytes in the corrosion cell were prepared similar to that of concrete pore solutions. Concrete prisms of 200 mm by 200 mm by 300 mm were used to determine the minimum immersion time for saturation. It was found that the optimum chloride content was 35 gm/L and the minimum immersion time for saturation was 140 hours. Accounting the results, a modified expression based on Faraday’s law was proposed to calculate weight loss due to corrosion. Journal of Engineering Science 11(1), 2020, 93-99


2008 ◽  
Vol 2 (2) ◽  
pp. 155-177 ◽  
Author(s):  
Eugene Brently Young
Keyword(s):  

Eternal return is the paradox that accounts for the interplay between difference and repetition, a dynamic at the heart of Deleuze's philosophy, and Blanchot's approach to this paradox, even and especially through what it elides, further illuminates it. Deleuze draws on Blanchot's characterisations of difference, forgetting, and the unlivable to depict the ‘sense’ produced via eternal return, which, for Blanchot, is where repetition implicates or ‘carries’ pure difference. However, for Deleuze, difference and the unlivable are also developed by the living repetition or ‘contraction’ of habit, which results in his distinctive characterization of ‘force’, ‘levity’, and sense in eternal return.


1970 ◽  
Vol 6 (1) ◽  
pp. 184-193
Author(s):  
Ольга Віговська

У статті теоретично обґрунтовано феномен конструктивного самозбереження особистості як ознаки самоактуалізації, розкриття власного потенціалу і побудови перспективи розвитку особистості та емпірично виявлено ознаки психологічної детермінації домінуючого інстинкту у конструктивній самореалізації жінок з різним соціальним статусом. Зазначено, що проблема самозбереження асоціюється з особливостями прояву інстинкту самозбереження людини, але потреби вищого порядку зумовлюють соціальну природу її поведінки, яка локалізована у найвищій точці самореалізації. Теоретично обгрунтовано, що самореалізація визначає тенденцію раціональної організації життя людини та проявляється у її почутті задоволеністю життям. З’ясовано, що психологічну основу конструктивного самозбереження становлять індивідуально-типологічні характеристики людини, які відображають психофізіологічні та психосоціальні резерви самореалізації особистості. Розроблена програма емпіричного дослідження, а також комплекс використаних методів математичної обробки результатів дослідження дає змогу конкретизувати психологічний зміст детермінації домінуючого інстинкту у конструктивній самореалізації жінок вікового діапазону 35-45 років та з різним соціальним статусом. У жінок, які виховують проблемну (хвору) дитину, домінує інстинкт "егофільного типу", що виражається у їх надмірному егоцентризмі і супроводжується низькими показниками самоактуалізації, на відміну від досліджуваних жінок, які виховують здорових дітей і у яких на фоні вираженої тенденції до самоактуалізації домінує базовий інстинкт "дослідницького типу" та "лібертофільного типу". This article theoretically proves constructive phenomenon of self identity as signs of self-disclosure own potential and prospects of development of individual construction. In addition, it empirically showes signs of psychological determination of the dominant instinct in a constructive self-determination of women with different social statuses. It was noted that the issue of self-preservation is associated with the peculiarities of manifestation of self-preservation instinct of man, but it needs higher-order cause social nature of the behavior that is localized at the highest point of self-realization. It theorized that self-realization determines the trend of rational organization of human life and manifests itself in its sense of life satisfaction. It was found that the psychological basis of constructive self-preservation of the individual make individually-typological characteristics of a person that reflect physiological and psychosocial reserves of self-realization. The developed program of empirical research, as well as the methods used complex mathematical processing of results of research allows to specify the content of the psychological determination of the dominant instinct of constructive self-realization а women age range of 35-45 years and with different social status. Women who bring up the problem child dominates the instinct of self-preservation, which is reflected in their excessive self-centeredness, and is accompanied by low levels of self-actualization, as opposed to the study of women who are raising healthy children and that against the backdrop of a pronounced tendency to self-actualization, dominated by basic instinct "research type" and "independent type."


Author(s):  
O. Yu. Atkov ◽  
S. G. Gorokhova

The individual dynamics of the allostatic load index was revealed mainly due to changes in the glucose level, body mass index, which makes it applicable for assessing the short-term adaptation to the stay in the conditions of shift work


2018 ◽  
Author(s):  
D. Basak ◽  
L. H. Ponce

Abstract Two case-studies on uncommon metals whiskers, performed at the Reliability Analysis Laboratory (RAL) of Northrop Grumman Innovation Systems, are presented. The components analyzed are an Oven Controlled Crystal Oscillator (OCXO) and an Electromechanical Relay. Investigative techniques were used to determine the chemical and physical makeup of the metal whiskers and develop an understanding of the underlying effects and mechanisms that caused the conditions conducive to whisker growth.


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