Academic literature on the topic 'W-Curve Theory of Transition'

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Journal articles on the topic "W-Curve Theory of Transition"

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Healey, J. J. "On the neutral curve of the flat-plate boundary layer: comparison between experiment, Orr–Sommerfeld theory and asymptotic theory." Journal of Fluid Mechanics 288 (April 10, 1995): 59–73. http://dx.doi.org/10.1017/s0022112095001066.

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The neutral stability curve for the flat-plate boundary layer has been calculated using the Orr–Sommerfeld equation and compared to those obtained using upper- and lower-branch scalings. The Orr–Sommerfeld results agree well with the lower-branch scaling at Reynolds numbers relevant to experiment, but agree well with the upper-branch scaling only for Rδ > 105. It is shown that the critical layer only emerges from the viscous wall layer when Rδ > 105. This suggests that for Rδ < 105, when the critical layer lies within the viscous wall layer, the disturbance has a triple-deck structure, even for the upper branch of the neutral curve (which can be reached if the phase jump across the critical layer is retained).The transition from a triple-deck to a five-deck structure with increasing Reynolds number on the upper branch occurs relatively abruptly and can be associated with a square-root branch point in the Tietjens function. Essentially, the lower- and upper-branch scalings pertain to two different modes, the first possessing a triple-deck structure, the second a five-deck structure. The modes are connected at the branch point, and the neutral curves of each mode join to give a single curve close to this branch point. The asymptotic expansions for the upper- and lower-branch neutral curves depend upon the analyticity of the dispersion relationship, and so the proximity of the branch point indicates where these expansions will be liable to inaccuracies. This explains the poor neutral-curve predictions made by five-deck analyses at the Reynolds numbers where transition occurs.
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CHIMELI, ARIASTER B., and JOHN B. BRADEN. "A capital scarcity theory of the environmental Kuznets curve." Environment and Development Economics 14, no. 5 (2009): 541–64. http://dx.doi.org/10.1017/s1355770x08004981.

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ABSTRACTThis paper offers a theory of the environmental Kuznets curve (EKC) based on the scarcity of capital relative to environmental quality. In a unified treatment of both market and transition economies of the former Soviet Bloc, we characterize a dynamic economy subject to two sources of market failure: a pollution externality and a pure public good ‘environmental quality’. We derive a policy rule to implement the social optimum in market and transition economies and show how, in general, a pollution tax or tradable permits can only implement the social optimum if accompanied by other taxes on consumption or profits.
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Umana, Anjalin, Mazumdar Abhijit, and Whiteside Erin. "Asian Students' Experience of Culture Shock and Coping Strategies." Journal of Education and Social Development 1, no. 1 (2017): 7–13. https://doi.org/10.5281/zenodo.834930.

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For international students, studying abroad has not been free from personal challenges. Not all students can adjust in an alien culture with ease. This research on Asian students’ experience of culture shock and coping strategies offers an understanding of the international students’ needs, adjustment difficulties, managing of anxiety and coping strategies. The research will be beneficial in generating ideas for better management of culture shock. In this study, Asian students of collectivist culture were recruited from the existing international student body of a university in the United States. The students willing to spare nearly an hour of their time for in-depth interviews were invited to participate. The data gleaned from the interviews were interpreted and analyzed using a theoretical thematic analysis following the work of Braun and Clarke (2006). Salient themes emerged while applying constant comparison technique in relation to the research questions. It was found that the Asian students' culture shock closely followed a W-curve theory of transition pattern of stages suggested by Zeller and Mosier (1993). It is natural for the Asian students to experience a roller coaster ride of cultural adjustment cycle once they embark on a journey abroad for education. Knowing about this pattern could make the transition easier. While students may at times find different cultural values in the host culture frustrating, yet there are positive sides in every approach to life.
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Lian, Peiqing, Taizhong Duan, Rui Xu, Linlin Li, and Meng Li. "Pressure behavior of shale-gas flow in dual porous medium based on fractal theory." Interpretation 6, no. 4 (2018): SN1—SN10. http://dx.doi.org/10.1190/int-2018-0002.1.

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The shale gas reservoir is a complex subject with a multiscale nanopore and fracture system, and the gas flow mechanism indicates an evident difference from the conventional gas reservoir. We have introduced fractal theory to characterize the multiscale distribution of pores and fractures, and we have developed a single-phase radial flow model considering nonequilibrium adsorption to describe the flow characteristics in the shale gas reservoir. The numerical solution of the flow model in Euclidean space is obtained by inversing the analytical solution derived in Laplace space through the Stehfest numerical inversion method, and the log-log curve of the dimensionless bottom-hole pressure (BHP) and its derivative versus dimensionless time are analyzed. The log-log curve of the dimensionless BHP has two distinct straight-line segments: The unit slope line reflects early well-storage effect, and the straight line with slope [Formula: see text] reflects reservoir fractal characteristics. The slope of the straight line will become smaller with the increasing fractal dimension. The adsorption coefficient mainly affects the middle and late period of the log-log curves, and more shale gas will desorb from the matrix with the increasing adsorption coefficient. The wellbore storage coefficient has a significant negative correlation with dimensionless BHP especially at the early and transitional stages. The skin factor mainly affects the transition section; a smaller skin factor generally leads to the earlier appearance of the transition section. In addition, a smaller interporosity flow coefficient also results in an earlier transition stage appearance. The lower storativity ratio means a higher dimensionless BHP and an earlier appearance of the transition stage.
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Zhou, Zhuo, Jiu Hui Wu, Xiao Liang, Xiao Yang Yuan, and Yun Lei Wang. "Research and derivation for Wien’s displacement law by using catastrophe theory." Modern Physics Letters B 34, no. 28 (2020): 2050304. http://dx.doi.org/10.1142/s0217984920503042.

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In this paper, Wien’s displacement law as one of the most important laws of thermal radiation, for which Wien has won the Nobel Prize in Physics, is studied and derived from the perspective of phase transition by using catastrophe theory. This paper describes in detail how the control variable causes the phase transition of the system potential function and the main indexes for judging whether the phase transition occurs. By extending the control variable in the catastrophe theory affecting the thermal radiation into multi-parameters form, the function equilibrium curve of the blackbody radiation is solved, and then the two expressions of Wien’s displacement law including wavelength-temperature and wavelength-temperature are derived theoretically. Furthermore, a phase transition method is proposed to study the thermal radiation of blackbody. This not only provides a new perspective for the research of thermal radiation, but also provides a new idea for the study of other phase transitions.
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Rai, D. P., and R. K. Thapa. "A Theoretical Study of Bulk Tungsten (W) Based on Momentum Transfer (q-Dependent)." Advances in Optics 2014 (October 8, 2014): 1–9. http://dx.doi.org/10.1155/2014/814909.

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The ground state electronic properties of bulk (W) were studied within the density functional theory (DFT). We have also analyzed the momentum- (q-) dependent loss function, dielectric constant, and optical conductivity (OC) within TD-DFT random-phase approximation (RPA). The loss function is plotted in the energy range 0–55 eV. The energy loss function spectrum shows four prominent peaks, two lower peaks below along with two sharp peaks above 30 eV. The different nature of peaks depends on the momentum transfer q. The peak caused by interband transition showed a less pronounced dispersion. From the dielectric function curve we have predicted the plasmon excitation at around 1.75 eV and calculated the corresponding plasma frequency (ωp)=26.585×1014 s−1.
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Li, Lingchao, Jinlong Liu, Weina Sun, and Baodong Cheng. "Advances in forest transition theory research." Sustainable Forestry 4, no. 2 (2021): 29. http://dx.doi.org/10.24294/sf.v4i2.1608.

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Forest transition is a trend change process from decreasing to increasing forest area in a country or region. Since the 1990s, ecological and environmental problems such as climate change and loss of biodiversity have received constant attention. The research theory and method of forest transformation has gradually become the frontier and hot topic pursued by international academic circle. With forest transformation as the theme, on the basis of introducing the origin of forest transformation research, along the development vein and internal logic of forest transformation research, this paper reviews the research progress of forest transition theory from the perspectives of Kuznets curve of forest environment and forest transition path, and summarizes the major issues in forest transformation research. The main direction of future research is proposed, including the impact of economic globalization on forest transition, the refinement of research units and the analysis of forest quality transition.
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Gu, Hanzhong, and Haruhisa Takahashi. "Exponential or Polynomial Learning Curves? Case-Based Studies." Neural Computation 12, no. 4 (2000): 795–809. http://dx.doi.org/10.1162/089976600300015592.

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Learning curves exhibit a diversity of behaviors such as phase transition. However, the understanding of learning curves is still extremely limited, and existing theories can give the impression that without empirical studies (e.g., cross validation), one can probably do nothing more than qualitative interpretations. In this note, we propose a theory of learning curves based on the idea of reducing learning problems to hypothesis-testing ones. This theory provides a simple approach that is potentially useful for predicting and interpreting (a diversity of) learning curve behaviors qualitatively and quantitatively, and it applies to finite training sample size and finite learning machine and for learning situations not necessarily within the Bayesian framework. We illustrate the results by examining some exponential learning curve behaviors observed in Cohn and Tesauro (1992)'s experiment.
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Wang, Qihui, Kun Chen, Kejia Liu, Lianbo Wang, Yu Chu, and Bichen Xie. "Study on Characterization of Phase Transition in Continuous Cooling of Carbon Steel Using In Situ Thermovoltage Measurement." Coatings 14, no. 8 (2024): 980. http://dx.doi.org/10.3390/coatings14080980.

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In this paper, a self-designed and enhanced thermovoltage measuring device was built to capture thermovoltage curves of 45 steel during continuous cooling. The phase zones of the thermovoltage curve were interpreted based on the Engel–Brewer electron theory and Fe-Fe3C phase diagram. The results show that the curve was stratified into three homogeneous phase zones and two-phase transition zones as follows: Zone Ι: single-phase austenite (A) zone; Zone III: austenite and ferrite (A+F) homogeneous phase zone; Zone V: ferrite and pearlite (P+F) homogeneous phase zone; Zone II: austenite to ferrite (A-F) phase transition zone; and Zone IV: austenite to pearlite (A-P) phase transition zone. Notably, the deflection point marked the transition temperature, which indicates that the thermovoltage curve can quantitatively characterize phase formation and transformation, as well as the phase transformation process. Furthermore, the sample was quenched at the measured ferrite phase transition temperature. Microstructure observations, electron probe microanalyzer (EPMA) and microhardness measurements corroborated our findings. Specifically, our experiments reveal ferrite precipitation first from the cold end at the phase transition temperature, leading to increased carbon content in adjacent austenite. The results of this study achieved the in situ characterization of bulk transformations during the materials heat treatment process, which expands the author’s research work conducted previously.
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Zawodna-Stephan, Marta. "Necrocommunitas. Badanie obozów koncentracyjnych w fazie przejściowej." Kultura i Społeczeństwo 63, no. 2 (2019): 39–59. http://dx.doi.org/10.35757/kis.2019.63.2.3.

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This text considers the question of how concentration camps in the transition phase can be studied. A transition phase appeared in certain camps a few months, weeks, or even days before the camp was liberated, and ended a few weeks later. As a result of the prisoners’ worsening living conditions, their high rate of mortality, and the weakening control of the camp staff , the social system that had been created in the camps fell apart and the new structures that would be established after liberation had not yet appeared. The author describes how certain concentration camps found themselves in a transition phase in the years 1944–1945, and then she provides two contrary ontological concepts (the theory of anomie and the theory of communitas) on which future research could be based. She pays particular attention to the meaning of dead bodies and the living’s relations with the dead. Consequently, she introduces the idea of necrocommunitas.
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Dissertations / Theses on the topic "W-Curve Theory of Transition"

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Ochirkhuyag, Myagmersuren. "Water Management in Mongolia." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-160459.

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The world experiences large-scale ecosystems degradation in an every part of the planet - in rich as well as in and poor parts. Unstable economic conditions together with weak law enforcements make low income countries face more severe forms of natural destruction. This draws the attention on the need to design economic policies that are environmentally sound and while at the same time ensuring the well-being of their inhabitants in economic, social and natural settings. A number of countries in Central and Eastern Europe and Central Asia have experienced a unique historical period of transition from communist regimes to free democratic societies. This has been followed by numerous effects on their financial situations as economic hardships caused by the collapse of economies injected by the assistance from the Soviet and committees of socialist countries mutually aiding each other, opening up of opportunities as private ownership and market liberations. Not all countries succeeded in liberalizing their economic structures and reforming economic and political environments. Simultaneously, the natural environment underwent various effects, both positive and negative, after the Iron Curtain fell and exposed destructing effects of command and control economy. Mongolia has experienced all the hard aspects of the transition and started to climb up on the income ladder from the low income to the lower middle-income list of the World Bank, but also seen many negative price aspects of development. Water resources have been severely degraded in recent years due to anthropogenic impact. However, there are reforms taking place in water sector institutions that have recently attracted wide attention nationwide.This thesis will give detailed picture on current state of water resources in the country and the system that coordinates them. The Environmental Kuznets Curve (EKC) is used as an approach to highlight the relationship between water resource quality and income per capita in Mongolia. This is followed by a detailed discussion on water institutions development and the coordinating mechanisms badly needed among sectors involved. The research suggests that collaborative actions are important if sustainable water management is to be reached. More generally, I recommend further research issues on the generated topic as my thesis is one of the first discussions coupling the EKC and institutional theory aspects together.
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Sheffield, Carolyn Evans. "Time-Resolved Infrared Spectroscopy and Density Functional Theory Study of Weak Interactions of Metal Carbonyls and Organic Solvents." Diss., CLICK HERE for online access, 2010. http://contentdm.lib.byu.edu/ETD/image/etd3389.pdf.

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Manning, Adrian Gordon. "Quantum Fields in Curved Spacetime with Cosmological and Gravitational Wave Implications." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/17804.

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A range of novel ideas, covering both general relativity and quantum field theory are introduced and explored. An analytic procedure for theories that modify the stress-energy-tensor in general relativity is examined which compares predicted deviations in the gravitational wave radiation from binary black hole mergers to the observed waveform from recent detections, i.e GW150914. This is applied directly to the theory of non-commutative spacetimes, which ultimately constrains the scale of non-commutative spacetime up to the Planck scale, some 15 orders of magnitude improvement on previous bounds. The stochastic background of gravitational wave radiation from first order electroweak phase transitions in the early universe is also examined. This is done in the context of the non-linearly realised electroweak sector of the Standard Model, which allows for a direct relation between coupling constants of the model and parameters of the expected stochastic gravitational wave background. For this particular model, a range of values are shown to not only produce gravitational waves detectable by future space-based detectors, such as eLISA, but can potentially create low-frequency radiation detectable by pulsar timing array experiments, such as the future SKA. Finally, non-inertial effects in the context of quantum fields in curved spacetimes are examined for a number of metrics. An oscillatory motion in the velocity expectation of a single fermionic particle is shown to exist in cosmological/expanding spacetimes, but not for accelerating or rotating spacetimes. In the rotating case, a new quantisation scheme is introduced along with the Bogoliubov coefficients enabling general calculations in rotating spaces to be computed with respect to defined non-rotating fermionic particle states.
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Hess, Christoph. "Propriétés de transport des bronzes oxygénés quasi-bidimensionnels à ondes de densité de charge, (PO2)4(WO3)2m(m=4 à 14)." Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10117.

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Nous avons etudie les proprietes de transport des bronzes quasi-bidimensionnels (po#2)#4(wo#3)#2#m (m=4 a 14). Ces composes subissent des transitions de peierls vers un etat a onde de densite de charge (odc) constituee d'une modulation de la densite electronique couplee a une distorsion periodique du reseau. Le parametre m est associe a l'epaisseur des feuillets conducteurs wo#6. Avec un nombre d'electrons de conduction constant par maille primitive, on peut etudier l'influence de la variation de la densite electronique et du caractere bidimensionnel sur les instabilites de peierls. Les mesures de magnetotransport dans les composes m=4 et m=6 ont ete interpretees a l'aide d'un modele a deux bandes indiquant que la surface de fermi (sf) dans l'etat odc est plus petite dans le compose m=6 que dans m=4. La destruction de la sf semble etre plus complete dans m=6 probablement par suite d'un caractere bidimensionnel plus accentue. Nous avons caracterise le compose m=5 par des mesures de proprietes de transport. Des oscillations quantiques de grande amplitude ont ete observees a basse temperature (t0. 3k) et sous fort champ magnetique (b27t). Leur analyse indique que la sf dans l'etat odc est quasicylindrique d'une taille superieure a celle des composes m=4 et 6. L'apparition de nouvelles frequences d'oscillation sous fort champ (b>18t) pourrait etre liee a un effet de rupture magnetique. Des etudes sur le compose m=7 ont conduit a la mise en evidence d'un etat supraconducteur a t#c=0. 3k. Le comportement galvanomagnetique de m=7 et m=8 a ete interprete dans le cadre d'un modele d'interferences quantiques, associe un desordre cristallin important dans la plupart des echantillons a grand m. Nous anvons compare les proprietes physiques a travers la serie : l'augmentation considerable des temperatures de transition de peierls et de la resistivite electrique en fonction de m a ete attribuee a un renforcement des correlations electroniques et du couplage electron-phonon.
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Caissie, Denis. "Paths towards self-discovery: transitional objects and intersubjectivity in four late-twentieth-century British novels." Thesis, Department of English, University of New Brunswick, 2003. http://hdl.handle.net/1882/47.

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This thesis explores the psychological development of liminal characters in four late-twentieth-century British novels. Studies of Julian Barnes’s Flaubert's Parrot, A. S. Byatt’s Possession, Angela Carter’s Nights at the Circus, and John Fowles’s The French Lieutenant’s Woman, by using D. W. Winnicott’s transitional-objects theory and Jessica Benjamin’s intersubjective theory, show how characters who are little more than infants socially and psychologically attempt to transcend the transitional, liminal status defined by Victor Turner. With the aid of significant objects or equal other subjects, these characters, whose subjective self-constructions at the beginning of the novels have become stalled in an immature position of emotional development or been inhibited by dominating individuals, progress psychologically towards controlling their own subjectivity.
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Vassura, Edoardo. "Path integrals on curved space and the worldline formalism." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13448/.

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Lo scopo primario di questa tesi e' l’analisi di una nuova procedura di regolarizzazione di path integral su spazi curvi, presentata inizialmente dal fisico J. Guven e applicata al caso di una teoria di campo scalare , ma mai utilizzata per svolgere ulteriori calcoli espliciti. Questa procedura, se corretta, permetterebbe di utilizzare il formalismo di path integral su spazi piatti anche nel caso in cui la varieta' di background risulti localmente curva. Tale procedura trasforma di fatto un modello sigma non lineare in un modello efficace lineare, permettando pertanto di aggirare le usuali complicazioni dovute alla generalizzazione di path integral. Una prova diretta della correttezza della procedura di Guven sembra mancare in letteratura: per questo motivo in questa tesi verranno eseguiti vari test volti a tale verifica. Alcuni errori sono stati riscontrati nella proposta iniziale, tra i quali un termine di potenziale che risulta essere non corretto. Ad ogni modo siamo stati in grado di identificare un potenziale che permetta di riprodurre correttamente i primi due coefficienti dell’espansione in serie dell’heat kernel. Utilizzando lo stesso metodo abbiamo poi cercato di ottenere il successivo coefficiente dell’espansione (cubico in termini di curvatura): il risultato ottenuto non risulta essere corretto, cosa che segnala il fallimento di tale metodo ad ordini superiori. Visti tali risultati preliminari, siamo stati indotti a considerare una classe speciale di spazi curvi, quella degli spazi massimamente simmetrici, trovando invece che su tali spazi la procedura di Guven riproduce i risultati corretti. Come verifica abbiamo ottenuto la parte diagonale dell’heat kernel, che ́ stata poi utilizzata per riprodurre l’anomalia di traccia di tipo A per campi scalari in dimensioni arbitrarie fino a D = 12. Questi risultati sono in accordo con quelli attesi. Viene pertanto fornita una prova della validita' di tale procedura su questi spazi.
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Ayed, Othman. "Etude des interactions entre atomes alcalins (li, na, k) et monoxyde de carbone en matrices de gaz rares : analyse en spectroscopie vibrationnelle et calcul quantiques de quelques complexes." Paris 6, 1987. http://www.theses.fr/1987PA066117.

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Dans le cas de li(le plus reactif), identification de li(co)::(n), ou n = 1,2,3,4,(ou 6), avec des frequences de vibration de valence de co plus perturbees que pour les metaux de transition carbonyle,et de li::(m) co, ou m = 2,3, avec frequences nu (co) abaissees. Pour na et k, observation d'especes de haute stoechiometrie (c::(n)o::(n))**(2-) (m**(+))::(2) ou n = 2,3,4, formees apres irradiation uv-visible et correspondant a des transformations chimiques. Essai d'interpretation de ces differences de reactivite par une description quantique des agregats de plus basse stoechiometrie : dans le complexe 1 :1, les deux etats electroniques inferieurs sont l'etat **(2)sigma non liant et l'etat **(2)pi liant; la courbe de potentiel de lico possede un minimum pour li-c equiv. A 2,5 a au-dessous de la courbe de l'etat **(2)pi alors que pour naco, le minimum de la courbe pour l'etat **(2)pi est au-dessous de la courbe de l'etat **(2)sigma ; le calcul met en evidence le caractere ionique de m::(2)c::(2)o::(2) (acetylenediolate) resultant d'une reaction chimique
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Rust, Maxim. "Procesy reprodukcji i cyrkulacji białoruskich i ukraińskich elit politycznych w latach 1991 - 2016." Doctoral thesis, 2019. https://depotuw.ceon.pl/handle/item/3354.

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Zakres pracy obejmuję proces ewolucji białoruskich i ukraińskich elit politycznych w okresie 1991-2016. Przedmiotem pracy są współczesne elity polityczne Białorusi i Ukrainy. Elity polityczne są opisane i porównane głównie na dwóch płaszczyznach: elity władzy (albo elity rządzące) oraz kontrelity. Problemem badawczym jest porównanie współczesnych białoruskich i ukraińskich elit politycznych pod względem ich pochodzenia, wewnętrznej struktury i zachodzących w nich procesów. Głównym celem rozprawy jest kompleksowy opis białoruskich i ukraińskich elit politycznych – skąd się wywodzą, jaka jest ich geneza, jakie procesy w nich zachodzą i na podstawie jakich kryteriów można je usystematyzować, a także wskazanie dominującego w każdym przypadku mechanizmu rekrutacji do samej elity. Drugim istotnym celem pracy jest analiza ewolucji elit politycznych w białoruskim i ukraińskim systemie politycznym. Celem teoretycznym jest próba zastosowania istniejących teorii elit w przypadkach białoruskim i ukraińskim, a celem praktycznym jest ich porównanie oraz próba sformułowania wspólnych wniosków. Białoruś przebyła specyficzną drogą transformacji, która wykształciła się w skonsolidowanym hybrydowym reżimie politycznym. W reżimie tym współistnieją elementy zarówno demokracji, jak i autorytaryzmu, a cechują go następujące elementy: skonsolidowana i silna elita rządząca z wyraźnym centrum (prezydent i jego otoczenie), słaba kontrelita, elastyczna ideologia państwowa, wielopoziomowa tożsamość oraz stosunkowo stabilna, zorientowana socjalnie gospodarka. System władzy ma wyraźny charakter patron-kliencki, wewnątrz systemu rywalizują różne grupy interesów, a modernizacja ma charakter autorytarny. Wskutek procesów monopolizacji przestrzeni politycznej i konsolidacji władzy, białoruska elita rządząca stała się elitą skonsolidowaną. Na jej obecny kształt wpłynął przede wszystkim proces częściowej wewnątrzgeneracyjnej reprodukcji przez konwersję, dlatego jest to elita zintegrowana ideologicznie. Białoruskie kontrelity również doświadczyły przede wszystkim procesu reprodukcji, a stałe funkcjonowanie w kontrolowanym i zmonopolizowanym otoczeniu politycznym niejednokrotnie doprowadzało do jej wewnętrznych podziałów. Dlatego białoruska kontrelita jest przykładem słabej elity sfragmentaryzowej. Podsumowując ewolucję i wzajemne relacje ukraińskich elit politycznych, należy stwierdzić, że największy wpływ na ich stan i kondycję miała cyrkulacja w pluralistycznym i względnie demokratycznym systemie. Ukraińskie elity polityczne funkcjonują w wielopłaszczyznowym i skomplikowanym otoczeniu, w którym działają autonomiczne i niezależne grupy interesów – klany regionalne i ugrupowania oligarchiczne, wywierające istotny wpływ zarówno na elity rządzące, jak i kontrelity. System funkcjonowania ukraińskich elit politycznych cechuje nasilenie wielopoziomowych nieformalnych powiązań i wzajemnych zależności. Regularnie występujące konflikty kompetencyjne między różnymi gałęziami władzy, dominacja osobistych ambicji i interesów, a także stosunkowo niski potencjał do osiągania kompromisów wewnątrz elity rządzącej, wpływają na jej wewnętrzne podziały, co czyni ją elitą sfragmentaryzowaną. W warunkach występowania dużej liczby aktorów wewnątrz kontrelit, w której każdy z nich dba o realizację partykularnych interesów, a różnice ideowe i programowe są bardzo silne, ukraińskie kontrelity można uznać za przykład elity wewnętrznie podzielonej.<br>The research field of the PhD thesis includes the process of evolution of Belarusian and Ukrainian political elites in the period 1991-2016. The subject of the study are contemporary political elites of Belarus and Ukraine. Political elite are described and compared on two levels: power elite (or ruling elite) and counter-elite. The research problem is the comparison of contemporary Belarusian and Ukrainian political elites in terms of their origin, internal structure and processes occurring in them. The main purpose of the dissertation is a comprehensive description of Belarusian and Ukrainian political elites - where they originate, what is their origin, what processes take place in them and what criteria can be systematized, as well as an indication of the recruitment mechanism that is the dominant in every case of political elite. The theoretical purpose is to apply existing elite theories in Belarusian and Ukrainian cases, and the practical aim is to compare them and attempt to formulate joint conclusions. Belarus is following its own way of transformation, which has developed into a consolidated hybrid political regime. In this regime elements of both democracy and authoritarianism coexist and are characterized by the following elements: a consolidated and strong ruling elite with a clear core (president and his surroundings), a weak counter-elite, a flexible state ideology, a multi-level identity and a relatively stable, socially oriented economy. The system of power has a clear patron-client character, various interest groups compete within the system, and modernization is authoritarian. As a result of the processes of monopolization of political space and consolidation of power, the Belarusian ruling elite has become a consolidated elite. Its current shape has been influenced primarily by the process of partial internal-generative reproduction through conversion, which is why it is an ideologically integrated elite. Belarusian counter-elite also experienced primarily the process of reproduction, and constant functioning in a controlled and monopolized political environment has often led to its internal divisions. This is why the Belarusian counter-elite is an example of a weak fragmentary elite. Summing up the evolution and mutual relations of the Ukrainian political elite, it should be noted that the biggest influence on their character and condition was circulation. In some of the crucial moments of Ukraine's recent political history, there were clear attempts to monopolize power. The Ukrainian political elite function in a multi-faceted and complicated environment in which autonomous and independent interest groups operate – these are regional and oligarchic clans that exert a significant influence both on the ruling elite and the counter-elite. Regularly occurring competence conflicts between various powers, the domination of personal ambitions and interests, as well as the relatively low potential for compromise within the ruling elite, affect its internal divisions, which make it a fragmented elite. Ukrainian counter-elite consists of very different political organizations. In the conditions of a large number of actors inside the counter-elite, in which each of them takes care of the implementation of particular interests, and program and ideological differences are very strong, Ukrainian counter-elite can be considered as an example of an internally divided elite.
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McArthur, Ian Albert. "Minimum entropy techniques for determining the period of W UMA stars." Diss., 2014. http://hdl.handle.net/10500/19898.

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This MSc report discusses the attributes of W Ursae Majoris (W UMa) stars and an investigation into the Minimum Entropy (ME) method, a digital technique applied to the determination of their periods of variability. A Python code programme was written to apply the ME method to photometric data collected on W UMa stars by the All Sky Automated Survey (ASAS). Starting with the orbital period of the binaries estimated by ASAS, this programme systematically searches around this period for the period which corresponds to the lowest value of entropy. Low entropy here means low scatter (or spread) of data across the phase-magnitude plane. The ME method divides the light curve plot area into a number of elements of the investigators choosing. When a particular orbital period is applied to this photometric data, the resulting distribution of this data in the light curve plane corresponds to a speci c number of data points in each element into which this plane has been divided. This data spread is measured and calculated in terms of entropy and the lowest value of entropy corresponds to the lowest spread of data across the light curve plane. This should correspond to the best light curve shape available from the data and therefore the most accurate orbital period available. Subsequent to the testing of this Python code on perfect sine waves, it was applied, and its results compared, to the 62 ASAS eclipsing binary stars which were investigated by Deb and Singh (2011). The method was then applied to selected stars from the ASAS data base.<br>School of Environmental Sciences<br>M. Sc. (Astronomy)
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Zdybel, Piotr Dariusz. "Kwantowe przemiany fazowe w spolaryzowanych mieszaninach ultrazimnych atomów fermionowych o nierównych masach." Doctoral thesis, 2022. https://depotuw.ceon.pl/handle/item/4104.

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This dissertation aims to investigate quantum phase transitions in polarized mixtures of ultracold fermionic atoms with unequal masses. In such systems, a leading instability of the Fermi sea is related to Cooper pairing in the s-wave channel. We will focus on the phase transition at the onset of the uniform super uid phase. Imbalanced Fermi mixtures possess a wide choice of control parameters, which allow tuning its properties. In particular, they provide a way to modify the characteristics of the phase transition at T = 0. In this thesis, we approach the problem of quantum phase transitions from three distinct but complementary perspectives. Firstly, we consider a mean- eld approximation and expand the e ective potential in powers of the order parameter (this is known as the Landau-Ginzburg theory). Of our particular interest is the possibility of suppressing the tricritical point to zero temperature, so that the transition remains continuous down to T = 0. Thus the system hosts a quantum critical point (QCP) in the phase diagram. We analytically identify such a possibility for a range of parameters in dimensionality d = 3, but on the other hand, we demonstrate that the QCP is excluded in d = 2 (at the mean- eld level). Moreover, taking into account a gradient term jr j2 in the e ective action, we show that it can be tuned to zero at T ! 0, which gives a route to realizing a quantum Lifshitz point. Secondly, we focus on the spectral properties of sound-like collective excitations (known as Anderson-Bogolyubov modes). Such excitations play a prominent role in the description of quantum criticality. We explore the origin of the complex pole of the pair uctuation propagator Fq, which gives dispersion relations of collective modes and its damping rates.We obtain the temporally non-local contributions to gradient expansion of F ��1 q , which correspond to the damping process of collective phonons. These terms allow us to derive analytical conditions under which damping is active. It turns out that Landau damping is exclusively present in the ordered phase for a large enough mismatch of the Fermi surfaces (even at T = 0). We subsequently compare this prediction with numerically obtained damping rates. Lastly, we perform a nonperturbative renormalization group (RG) analysis using its one-particleirreducible variant.We consider a situation in which the quantum phase transition is continuous at the mean- eld level. Then one nds that order-parameter uctuations, introduced by the Landaudamping term, obstruct the RG ow toward the Wilson-Fisher xed point at su ciently low T , which may indicate a rst-order transition. Upon increasing T , the impact of damping ceases, and a critical scaling characterized by the dynamical exponent z = 1 is observed. In this case, the system shows a quantum-classical crossover at T > 0. Moreover, without damping, the QCP is stable with respect to uctuations and the transition remains second-order.<br>Niniejsza rozprawa ma na celu zbadanie kwantowych przemian fazowych w spolaryzowanych mieszaninach ultrazimnych atomów fermionowych o nierównych masach.Wtakich układach wiodaca niestabilnosc morza Fermiego jest zwiazana z parowaniem Coopera w kanale fal parcjalnych s. Skoncentrujemy sie na przejsciu fazowym zachodzacym miedzy jednorodna faza nadciekła, a faza normalna. Niezrównowazone mieszaniny Fermiego posiadaja szeroki wybór parametrów kontroli, które pozwalaja na dostrajanie ich własciwosci. W szczególnosci daja one mozliwosc zmody kowania cech przemiany fazowej w T = 0. W tej dysertacji, podchodzimy do problemu kwantowych przemian fazowych z trzech róznych, ale uzupełniajacych sie perspektyw. Po pierwsze rozwazamy przyblizenie sredniego pola i rozwijamy efektywny potencjał w potegach parametru porzadku (co jest znane jako teoria Landaua-Ginzburga). Szczególnie jestesmy zainteresowani mozliwoscia sprowadzenia punktu trójkrytycznego do zerowej temperatury w taki sposób, ze przemiana fazowa pozostaje ciagła w granicyT ! 0.Wten sposób badany układ zawiera kwantowy punkt krytyczny (QCP) na diagramie fazowym. Analitycznie identy kujemy taka mozliwosc dla zakresu parametrów układu w trzech wymiarach (d = 3). Z drugiej strony pokazujemy, ze wystepowanie QCP jest wykluczone wd = 2 (na poziomie pola sredniego). Co wiecej uwzgledniajac wyrazy gradientowe o postaci jr j2 w efektywnym działaniu stwierdzamy, ze mozna je sprowadzic do zera w granicy T ! 0 poprzez manipulacje parametrami układu, co pozwala na zrealizowanie kwantowego punktu Lifszyca. Po drugie skupiamy sie na własnosciach spektralnych fononowych modów kolektywnych (znanych jako mody Andersona-Bogoliubowa).Wzbudzenia te pełnia istotna role w opisie kwantowych zjawisk krytycznych. Badamy pochodzenie zespolonego bieguna propagatora uktuacji parowania Fq, który pozwala na znalezienie relacji dyspersji modów kolektywnych oraz ich współczynników tłumienia. Otrzymujemy nielokalne w czasie wkłady do rozwiniecia gradientowego propagatora F �1 q , które sa zwiazane z procesem tłumienia fononów Andersona-Bogoliubowa. Wyrazenia te pozwalaja na wyprowadzenie analitycznego kryterium wystepowania tłumienia Landaua. Okazuje sie, ze jest ono obecne wyłacznie w fazie uporzadkowanej dla odpowiednio duzego niedopasowania powierzchni Fermiego składników mieszaniny (co ma miejsce takze dla T = 0). Nastepnie porównujemy otrzymane przewidywania z numerycznie obliczonymi współczynnikami tłumienia. Na koniec przeprowadzamy analizewykorzystujaca nieperturbacyjna grupe renormalizacji (RG). Interesuje nas sytuacjawktórej kwantowa przemiana fazowa jest ciagła na poziomie pola sredniego. Pokazujemy, ze uktuacje parametru porzadku, wprowadzone przez człon tłumienia, destabilizuja płyniecie RG w kierunku punktu stałego Wilsona-Fishera dla odpowiednio niskichT , co moze oznaczac wystepowanie przemiany I rodzaju. Przy zwiekszaniuT wpływ tłumienia znika i obserwuje sie skalowanie krytyczne scharakteryzowane wykładnikiem dynamicznym z = 1. W tym przypadku układ wykazuje ciagłe przejscie miedzy rezimem kwantowym i klasycznym dla T > 0. Co wiecej, przy braku tłumienia, QCP jest stabilny ze wzgledu na uktuacje i przemiana fazowa pozostaje II rodzaju.
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Books on the topic "W-Curve Theory of Transition"

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Perkins, Lee. Railroad Taper: The Theory and Application of a Compound Transition Curve Based upon Thirty-Foot Chords. Creative Media Partners, LLC, 2018.

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Railroad Taper: The Theory and Application of a Compound Transition Curve Based upon Thirty-Foot Chords. Creative Media Partners, LLC, 2022.

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Searles, William Henry. Railroad Spiral: The Theory of Compound Transition Curve Reduced to Practical Formulae and Rules for Application in Field Work. Creative Media Partners, LLC, 2018.

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Searles, William Henry. Railroad Spiral: The Theory of the Compound Transition Curve Reduced to Practical Formulæ and Rules for Application in Field Work. Creative Media Partners, LLC, 2018.

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Desperak, Izabela. Płeć zmiany. Zjawisko transformacji w Polsce z perspektywy gender. Wydawnictwo Uniwersytetu Łódzkiego, 2013. http://dx.doi.org/10.18778/7525-943-8.

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Study focuses on the issue of social change, based on transition process in Poland, analysed through gender perspective. Although many books and reports on both transition and women’s social position have been conducted and published before, studies joining those two perspectives were rare. The analysis bases on contemporary sociological theories of social change, concerning gender: Manuel Castells’s idea of the end of patriarchy, Ronald Inglehart and Pippa Norris concept of rising tide of gender equality and cultural change, theory of new gender contract formulated by Małgorzata Fuszara and Anthony Giddens’s idea of democratisation in private sphere. The book includes also wide account on history of gender issues in sociological theories and its contemporary position in mainstream social science. It also presents main theoretical approaches to social phenomena of gender inequality, and summarises key issues of research.
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Grolnick, Simon, and Leonard Barking. Between Reality and Fantasy: Transitional Objects and Phenomena. Jason Aronson, 1988.

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Caldwell, Lesley, and Helen Taylor Robinson, eds. The Collected Works of D. W. Winnicott. Oxford University Press, 2016. http://dx.doi.org/10.1093/med:psych/9780190271367.001.0001.

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Volume 4 (1952–1955) is introduced by the distinguished Canadian analyst, Dominique Scarfone. It contains texts of further BBC broadcasts and papers on Winnicott’s contribution to the psychoanalytic study of psychosis and the meaning of regression in analysis. There are letters to members of the British Society and reviews of contemporary books, including a review, with Masud Khan, of Ronald Fairbairn’s Psychoanalytic Studies of the Personality. This volume contains the first published version of ‘Transitional Objects and Transitional Phenomena’ and the whole case history Holding and Interpretation, first published posthumously in 1972 and then in 1986, but based on detailed case notes for a patient seen 1940–1941 and from 1953, and written between January and July 1955.
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Cox, Tory, Terence Fitzgerald, and Michelle Alvarez, eds. The Art of Becoming Indispensable. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780197585160.001.0001.

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Despite their academic preparation and lived experiences, new school social workers face a learning curve when moving from entry-level practice to proficiency. The Art of Being Indispensable: What School Social Workers Need to Know in Their First Three Years of Practice is the first book focusing specifically on the needs of new school social workers as they transition to this complex role. Each of the book’s 20 chapters features an academic scholar and at least one school social work practitioner; overall, there are 18 academics and 42 practitioners from 28 different states. The diversity of the authors’ experiences, representing all variations of schools and districts, ensures that the content is applicable to a variety of practice contexts. Each chapter addresses the challenges of a public health pandemic and the impact of racial injustice. There is a timeless quality to this text since every year, new school social workers are being hired, whether from master of social work and bachelor of social work programs or from the ranks of professional social workers changing fields and becoming school social workers. This indispensable guide will help new school social workers to effectively execute their roles and responsibilities.
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Caldwell, Lesley, and Helen Taylor Robinson, eds. The Collected Works of D. W. Winnicott. Oxford University Press, 2016. http://dx.doi.org/10.1093/med:psych/9780190271411.001.0001.

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Volume 9, 1969–1971, introduced by the Swedish training analyst and former president of the Swedish Society, Arne Jemstedt, contains a selection of letters from the last years of Winnicott’s life. The work includes further developments of his work on envy, the use of an object, psychosomatics, the impact of the mother’s unconscious, living creatively, communication, adolescence and rebellion and the final version of transitional objects and transitional phenomena. There are also topical pieces on the moon landing, the contraceptive pill and the building of the Berlin Wall. The volume includes Winnicott’s introduction to Playing and Reality (his most successful book), published in 1971 after his death. Finally, this volume includes a section of various short notes and ideas which could not be reliably dated.
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Maggiore, Michele. Gravitational Waves. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198570899.001.0001.

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A comprehensive and detailed account of the physics of gravitational waves and their role in astrophysics and cosmology. The part on astrophysical sources of gravitational waves includes chapters on GWs from supernovae, neutron stars (neutron star normal modes, CFS instability, r-modes), black-hole perturbation theory (Regge-Wheeler and Zerilli equations, Teukoslky equation for rotating BHs, quasi-normal modes) coalescing compact binaries (effective one-body formalism, numerical relativity), discovery of gravitational waves at the advanced LIGO interferometers (discoveries of GW150914, GW151226, tests of general relativity, astrophysical implications), supermassive black holes (supermassive black-hole binaries, EMRI, relevance for LISA and pulsar timing arrays). The part on gravitational waves and cosmology include discussions of FRW cosmology, cosmological perturbation theory (helicity decomposition, scalar and tensor perturbations, Bardeen variables, power spectra, transfer functions for scalar and tensor modes), the effects of GWs on the Cosmic Microwave Background (ISW effect, CMB polarization, E and B modes), inflation (amplification of vacuum fluctuations, quantum fields in curved space, generation of scalar and tensor perturbations, Mukhanov-Sasaki equation,reheating, preheating), stochastic backgrounds of cosmological origin (phase transitions, cosmic strings, alternatives to inflation, bounds on primordial GWs) and search of stochastic backgrounds with Pulsar Timing Arrays (PTA).
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Book chapters on the topic "W-Curve Theory of Transition"

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Popov, Valentin L. "Adhesion Hysteresis Due to Chemical Heterogeneity." In Springer Tracts in Mechanical Engineering. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-60124-9_20.

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AbstractAccording the JKR theory of adhesivecontact, changes of the contact configuration after formation of the adhesive neck and before detaching are completely reversible. This means, that after formation of the initial contact, the force-distance dependencies should coincide, independently of the direction of the process (indentation or pull-off). In the majority of real systems, this invariance is not observed. The reasons for this may be either plastic deformation in the contacting bodies or surface roughness. One further mechanism of irreversibility (and corresponding energy dissipation) may be chemical heterogeneity of the contact interface leading to the spatial dependence of the specific work of adhesion. In the present paper, this “chemical” mechanism is analyzed on a simple example of an axisymmetric contact (with axisymmetric heterogeneity). It is shown that in the asymptotic case of a “microscopic heterogeneity”, the system follows, during both indentation and pull-off, JKR curves, however, corresponding to different specific surface energies. After the turning point of the movement, the contact area first does not change and the transition from one JKR curve to the other occurs via a linear dependency of the force on indentation depth. The macroscopic behavior is not sensitive to the absolute and relative widths of the regions with different surface energy but depends mainly on the values of the specific surface energy.
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Hornkohl, Aaron D. "The Origins of Wayyiqṭol." In Interconnected Traditions: Semitic Languages, Literatures, Cultures—A Festschrift for Geoffrey Khan. Open Book Publishers, 2025. https://doi.org/10.11647/obp.0463.02.

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In this study, the writer explores Geoffrey Khan’s groundbreaking theory on the developmental history of the Biblical Hebrew wayyiqṭol form. After summarising earlier research on phonological and transcriptional evidence, the article details Khan’s claim, based on typological parallels from Amarna Canaanite and Neo-Aramaic and using Construction Grammar, that wayyiqṭol developed (by means of schematisation and secondary gemination to distinguish preterite semantics from volitional or purposive meanings) from a semantically undifferentiated Iron Age w-yiqṭol construction into a specialised form signalling discourse dependency and temporal posteriority. The study then analyses first-person w-yiqṭol morphology—preterite and volitive/purposive—across diverse corpora, complementing Khan’s study with a more detailed exploration of the diachronic dimension in usage and formal variation. Among important observations is the transition from strict morphological distinctions in early sources (represented by the Masoretic Pentateuch) to increased conflation in later texts in both semantic values. While this study deepens understanding of Biblical Hebrew verb forms, it also raises questions about their functional dynamics in pre-Tiberian traditions, as well as their eventual codification in the Masoretic system.
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Celletti, Alessandra, Gabriella Della Penna, and Claude Froeschlé. "Estimate of the Transition Value of Librational Invariant Curves." In Modern Celestial Mechanics: From Theory to Applications. Springer Netherlands, 2002. http://dx.doi.org/10.1007/978-94-017-2304-6_16.

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Ying, S. C., and G. Y. Hu. "Theory of Commensurate-Incommensurate Phase Transitions in W(001)." In The Structure of Surfaces. Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-82493-7_55.

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Sato, Yasuomi D., Keiji Okumura, and Masatoshi Shiino. "Model Studies on Time-Scaled Phase Response Curves and Synchronization Transition." In Neural Information Processing. Theory and Algorithms. Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-17537-4_12.

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Ossola, Alessandro, and Brenda Lin. "Accelerating Climate Innovation in Cities." In Theory and Practice of Urban Sustainability Transitions. Springer Nature Singapore, 2024. https://doi.org/10.1007/978-981-97-7671-9_4.

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AbstractThe rate at which climate action is currently achieved is often outpaced by the increasing speed of climate impacts in many urbanised regions globally. Actions related to coping with climate extremes, improving adaptive responses, and ultimately transforming cities for climate resilience have had variable success and have often failed to be implemented at scale. Climate stresses and impacts are accelerating; current climate action is not, at least not fast enough.Here we propose a novel conceptual framework based on the concept of ‘climate innovation’: the pervasive, strategic application of new and yet-to-be-born ideas, knowledge, and technology that can significantly accelerate the mitigation of climate change impacts and realise climate adaptation in human societies.We identify a typology of climate innovations—incremental, sustaining, radical, and disruptive—highlighting possible foci and examples of innovations. We further discuss how climate innovation and adoption curves, as well as innovation series, could be idealised and implemented to fast-track climate change mitigation and adaptation strategies at multiple scales.This framework can hopefully help societies and decision-makers to better contextualise how meaningful climate action can be envisioned, prioritised, and implemented—and discontinued when it fails to accelerate climate innovations and meet climate goals in increasingly accelerated timeframes.
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Sahu, D., S. C. Ying, and J. M. Kosterlitz. "Theory of Phase Transitions on H/W(110) and H/Mo(110) Systems." In Springer Series in Surface Sciences. Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73343-7_77.

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Moriarty, John A. "High-Temperature Properties, Melting and Phase Diagrams." In Theory and Application of Quantum-Based Interatomic Potentials in Metals and Alloys. Oxford University PressOxford, 2023. http://dx.doi.org/10.1093/oso/9780198822172.003.0008.

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Abstract In this chapter, the treatment of thermodynamic properties, phase stability and phase transitions in metals via quantum-based interatomic potentials (QBIPs) is extended to high temperature (high T), including anharmonic vibrational effects in the solid, liquid-state structure and energetics and pressure-temperature phase diagrams. In addition to standard molecular dynamics (MD) techniques, the tools of reversible-scaling MD and variational perturbation theory are introduced to obtain accurate solid and liquid free energies. Respective pair and multi-ion QBIPs from generalized pseudopotential theory (GPT) for the simple metal Mg and from model-GPT for the transition metal Ta are used to illustrate a wide range of high-T solid and liquid applications of interest at both ambient pressure and high pressure. These applications include calculations of the specific heat, thermal expansion coefficient, elastic moduli, shock Hugoniot and melt curve, with detailed comparison to experiment. Also discussed in the case of Ta are large-scale MD simulations of rapid solidification and high-T solid polymorphism.
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Kübler, Jürgen. "Electronic Structure and Magnetism." In Theory of Itinerant Electron Magnetism, 2nd Edition. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780192895639.003.0004.

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The fundamental magnetic properties of iron, cobalt, and nickel are the center of interest, beginning with historical attempts and Stoner’s theory. Stoner susceptibility is derived in a modern way by Janak finding that only those three carry a magnetic moment in elementary metals. The energy-band structures of all transition elements are connected with their repective phase stability which is obtained by means of density-functional calculations. The band structure of the ferromagnetic metals is obtained and compared with angle-resolved photoemission data. The electronic structure of the antiferromagnetic metals, Cr, Mn, and fcc Fe is clarified. Next, the magnetic moments of transition-metal compounds are classified by means of the Slater–Pauling curve and a large number of compounds are half-metallic supplying spin-polarized transport. Multilayers realize oscillatory exchange and show unusual electronic properties such as giant magnetoresistance which is discussed in detail. Tunnel junctions supply spin valves. Relativistic effects in solids are of importance for magnetocrystalline anisotropy and spectroscopic effects. Kubo theory supplies the basic understanding of the magneto-optical Kerr effect for which a number of examples are given. Noncollinear magnetic order reveals novel interaction mechanisms, such as the Dzyaloshinsky–Moriya interaction. The Berry phase explains the anomalous Hall effect as well as the Nernst effect and leads to the field of topology in the solid state. Weyl fermions are also explored.
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Kia, Amir. "Positive Interest Rate, Stationary Economy, and Inefficiency." In Handbook of Research on Theory and Practice of Global Islamic Finance. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-0218-1.ch001.

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This chapter analyses the direct impact of a positive rate of interest (usury) on the production possibility curve. Usury under a stationary state creates inefficiency in the sense that the marginal rate of transformation is not equal to the price ratio. Over the short run Pareto efficiency appears when a transition period is considered and the rate of return moving from one state to another is endogenous and equals the rate of investment. In a non-stationary economy, when a positive rate of return (interest) is equal to the growth rate of the economy, there will be a Pareto-efficient equilibrium. But if the interest rate is exogenous to the system, usury exists, and then Pareto efficiency cannot be achieved under any state, either stationary or non-stationary.
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Conference papers on the topic "W-Curve Theory of Transition"

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McDonald, Molly A., and Christos T. Maravelias. "Stochastic Programming Models for Long-Term Energy Transition Planning." In Foundations of Computer-Aided Process Design. PSE Press, 2024. http://dx.doi.org/10.69997/sct.107593.

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With growing concern over the effects of green-house gas emissions, there has been an increase in emission-reducing policies by governments around the world, with over 70 countries having set net-zero emission goals by 2050-2060. These are ambitious goals that will require large investments into the expansion of renewable and low-carbon technologies. The decisions about which technologies should be invested in can be difficult to make since they are based on information about the future, which is uncertain. When considering emerging technologies, a source of uncertainty to consider is how the costs will develop over time. Learning curves are used to model the decrease in cost as the total installed capacity of a technology increases. However, the extent to which the cost decreases is uncertain. To address the uncertainty present in multiple aspects of the energy sector, multistage stochastic programming is employed considering both exogenous and endogenous uncertainties. It is observed in scenarios when costs of emerging technologies decrease to competitive prices, decisions to invest in these technologies should be made earlier to allow for the decrease in costs to be taken advantage of in the future. Noticeably, a wider variety of energy and biofuel technologies are invested in when uncertainty is included. Interestingly, it is also seen that there are lower carbon emissions when uncertainty is considered.
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Wang, Z. X., H. M. Li, Y. J. Chao, and P. S. Lam. "Prediction of Characteristic Length and Fracture Toughness in Ductile-Brittle Transition." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61608.

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Finite element method was used to analyze the three-point bend experimental data of A533B-1 pressure vessel steel obtained by Sherry, Lidbury, and Beardsmore [1] from −160 to −45 °C within the ductile-brittle transition regime. As many researchers have shown, the failure stress (σf) of the material could be approximated as a constant. The characteristic length, or the critical distance (rc) from the crack tip, at which σf is reached, is shown to be temperature dependent based on the crack tip stress field calculated by the finite element method. With the J-A2 two-parameter constraint theory in fracture mechanics, the fracture toughness (JC or KJC) can be expressed as a function of the constraint level (A2) and the critical distance rc. This relationship is used to predict the fracture toughness of A533B-1 in the ductile-brittle transition regime with a constant σf and a set of temperature-dependent rc. It can be shown that the prediction agrees well with the test data for wide range of constraint levels from shallow cracks (a/W = 0.075) to deep cracks (a/W = 0.5), where a is the crack length and W is the specimen width.
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Cicero, Sergio, Tiberio Garcia, and Virginia Madrazo. "On the Use of the Notch Master Curve for Apparent Fracture Toughness Predictions of Notched Ferritic Steels Operating Within the Ductile-to-Brittle Transition Zone." In ASME 2015 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/pvp2015-45043.

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This paper presents the Notch-Master Curve as a model for the prediction of the apparent fracture toughness of ferritic steels in notched conditions and operating at temperatures corresponding to their ductile-to-brittle transition zone. The Notch-Master Curve combines the Master Curve of the material in cracked conditions and the notch corrections provided by the Theory of Critical Distances. In order to validate the model, the fracture resistance results obtained in fracture tests performed on notched CT and SENB specimens are presented. The results gathered here cover four ferritic steels (S275JR, S355J2, S460M and S690Q), three different notch radii (0.25 mm, 0.50 mm and 2.0 mm) and three different temperatures within the corresponding ductile-to-brittle transition zone. The results demonstrate that the Notch Master Curve provides good predictions of the fracture resistance in notched conditions for the four materials analyzed.
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Shirinyan, Aram, Yuriy Bilogorodskyy, and Oleksiy Krit. "Simulating the vacancy saturation effect on phase changes in irradiated nanoparticles using the steady-state approach in chemical rate theory." In IXth INTERNATIONAL SAMSONOV CONFERENCE “MATERIALS SCIENCE OF REFRACTORY COMPOUNDS”. Frantsevich Ukrainian Materials Research Society, 2024. http://dx.doi.org/10.62564/m4-as2232.

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The objective of the research is to propose a thermodynamic approach to describe the effects of vacancy saturation on the phase stability of solid nanoparticles during irradiation and to employ the steady-state approach in chemical rate theory to account for radiation defect concentrations. The research is applicable for polymorphic phase transitions in metals (Mo, V, W, Ti, Tl, Zr) and amorphization in ceramics (SiC, TiC). The study demonstrates, via simulation, the potential for radiation-induced α-phase to β-phase transitions and stable radiation zones in initially crystalline nanoparticles. Two model approximations are considered: one resembling iron-like metals with a polymorphic phase transition (α phase is bcc, β phase is fcc) and another resembling SiC-like ceramics with amorphization (α phase is cubic or hexagonal polytype of SiC, β phase is amorphous SiC). Parameters for irradiation include 1MeV ions with fluences ranging from 10 15 to 2×10 16 ions/cm² per second, and defect generation rates (K V ) of nearly 10 -3 - 10 -4 dpa/s for metals and 10 -12 dpa/s for ceramics, vacancy migration energies of 1-2eV for metals and nearly 4eV for crystalline ceramics. Our model study reveals that very small α-phase (bcc) particles are unstable, and α to β phase transformations can occur independently of irradiation. However, in certain scenarios, nucleation of the β-phase necessitates a significant additional energy change, leading to a low probability of α to β phase transition. For larger particle sizes and lower temperatures, α to β transformation becomes impossible regardless of irradiation. Crystalline ceramic materials generally demonstrate notably higher values for the energy of vacancy migration. This implies that the impact of radiation on phase transitions in ceramics is likely to be more significant. In contrast, nanoscale metals exhibit greater resistance to irradiation and thus may be recommended for nuclear materials.
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Cicero, Sergio, Tiberio García, Virginia Madrazo, Jorge Cuervo, Estela Ruiz, and Federico Gutiérrez-Solana. "Analysing the Notch Effect Within the Ductile-to-Brittle Transition Zone of S275JR Steel." In ASME 2013 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/pvp2013-97017.

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This paper analyses the notch effect in ferritic-pearlitic steel S275JR in a range of temperatures within the material Ductile-to-Brittle Transition Zone (DBTZ). The notch effect is evaluated in terms of load-bearing capacity, apparent fracture toughness (modeled here using the Theory of Critical Distances) and fracture micromechanisms. The concept of Master Curve in notched conditions is also presented. To this end, experimental results obtained in S275JR notched specimens are presented, together with Scanning Electron Microscopy (SEM) fractographies. The analysis is performed at −50 °C, −30 °C and −10 °C, the material Transition Temperature (T0) being −26.1 °C, with the notch radii ranging from 0 mm (crack-type defects) up to 2.0 mm. The results show how the lower the temperature the larger the notch effect, and also that the evolution of both the load bearing capacity and the apparent fracture toughness is directly related to the evolution of fracture micromechanisms. Moreover, the proposed Master Curve in notched conditions has provided good predictions of the experimental results.
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Sánchez, Marcos, Sergio Cicero, Florian Obermeier, Marta Serrano, Yu-Lung Chiu, and Eberhard Altstadt. "On the Possibility of Extending the Crack Length Criterion in the Master Curve Methodology." In ASME 2024 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2024. http://dx.doi.org/10.1115/pvp2024-122502.

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Abstract The master curve methodology is a well-known approach utilized to characterize the ductile-to-brittle transition region of ferritic-pearlitic steels. This methodology was initially standardized in ASTM E1921 in 1997 and has undergone continuous evolution and improvement since its origin. However, the validity criterion for the crack aspect ratio (0.45 ≤ a0/W ≤ 0.55) has remained unchanged since its inception. It is worth noting that this criterion was originally established in accordance with standard ASTM E399, which characterizes fracture conditions under linear-elastic plane strain conditions, apparently for historical precedents rather than any scientific rationale. Furthermore, ASTM E1820, which is employed to characterize the fracture behavior of metallic materials in elastic-plastic conditions, permits a maximum crack length-to-width ratio of 0.70. In this context, and considering that ASTM E1921 measures KJc (elastic-plastic) values of the fracture toughness, our research seeks to empirically demonstrate that the crack length-to-width criteria established in ASTM E1921 can be increased up to 0.60, at the very least, without compromising the accuracy of the reference temperature calculations. Such a correction would offer significant advantages, especially when dealing with mini-C(T) specimens. Their tiny dimensions may result in the discarding of numerous specimens that could otherwise be effectively employed for reference temperature calculations.
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7

Al Barwani, Mohsin, and Jae Sung Park. "Dynamics of Laminar-to-Turbulent Transition in a Wall-Bounded Channel Flow Up to Re=40,000." In ASME 2022 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/imece2022-94489.

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Abstract The transition from laminar to turbulent flow is of great interest since it is one of the most difficult and unsolved problems in fluids engineering. The transition processes are significantly important because the transition has a huge impact on almost all systems that come in contact with a fluid flow by altering the mixing, transport, and drag properties of fluids even in simple pipe and channel flows. Generally, in most transportation systems, the transition to turbulence causes a significant increase in drag force, energy consumption, and, therefore, operating cost. Thus, understanding the underlying mechanisms of the laminar-to-turbulent transition can be a major benefit in many ways, especially economically. There have been substantial previous studies that focused on testing the stability of laminar flow and finding the critical amplitudes of disturbances necessary to trigger the transition in various wall-bounded systems, including circular pipes and square ducts. However, there is still no fundamental theory of transition to predict the onset of turbulence. In this study, we perform direct numerical simulations (DNS) of the transition flows from laminar to turbulence in a channel flow. Specifically, the effects of different magnitudes of perturbations on the onset of turbulence are investigated. The perturbation magnitudes vary from 0.001 (0.1%) to 0.05 (5%) of a typical turbulent velocity field, and the Reynolds number is from 5,000 to 40,000. Most importantly, the transition behavior in this study was found to be in good agreement with other reported studies performed for fluid flow in pipes and ducts. With the DNS results, a finite amplitude stability curve was obtained. The critical magnitude of perturbation required to cause transition was observed to be inversely proportional to the Reynolds number for the magnitude from 0.01 to 0.05. We also investigated the temporal behavior of the transition process, and it was found that the transition time or the time required to begin the transition process is inversely correlated with the Reynolds number only for the magnitude from 0.02 to 0.05, while different temporal behavior occurs for smaller perturbation magnitudes. In addition to the transition time, the transition dynamics were investigated by observing the time series of wall shear stress. At the onset of transition, the shear stress experiences an overshoot, then decreases toward sustained turbulence. As expected, the average values of the wall shear stress in turbulent flow increase with the Reynolds number. The change in the wall shear stress from laminar to overshoot was, of course, found to increase with the Reynolds number. More interestingly was the observed change in wall shear stress from the overshoot to turbulence. The change in magnitude appears to be almost insensitive to the Reynolds number and the perturbation magnitude. Because the change in wall shear stress is directly proportional to the pumping power, these observations could be extremely useful when determining the required pumping power in certain flow conditions. Furthermore, the stability curve and wall shear stress changes can be considered robust features for future applications, and ultimately interpreted as evidence of progress toward solving the unresolved fluids engineering problem.
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8

Lawandy, Nabil M. "Light-induced transport and delocalization in transparent materials." In OSA Annual Meeting. Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.tuii4.

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When an intense nonresonant field interacts with a two-level system, the wavefunctions are modified. Several approaches may be used to study this problem including the techniques of dressed state theory. When the two-level system is comprised of two midgap sites separated by a distance Rab and an energy in the absence of light shifts Wba, the light shifted energy separation becomes This effect acts on level pairs and therefore shifts all the energy levels closer to each other. With these results and the rough criteria for Anderson localization W &gt; B (B is the energy bandwidth), we may arrive at a condition for which a transition from localized to extended states could occur. The resulting critical intensity is given by Using typical values of R = 15 Å, v = 3 ×1014 Hz, α = 0.2 AX−1, and W = 0.4 eV, we arrive at critical intensity for delocalization of I c = 10GW/cm2.
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Refan, Maryam, and Horia Hangan. "Experimental and Theoretical Study on the Aerodynamic Performance of a Small Horizontal Axis Wind Turbine." In ASME 2010 Power Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/power2010-27174.

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An upwind, three-bladed small horizontal axis wind turbine (HAWT) with a rotor of 2.2 m in diameter is tested in the Boundary Layer Wind Tunnel Laboratory II (BLWTL II). The power output of the turbine is measured for free stream velocities ranging from 1 m/s to 9 m/s. The blade element momentum (BEM) theory is implemented to predict the power curve of the HAWT. The theoretical characteristics of the turbine are discussed in terms of power and torque coefficients and the experimental results are compared to the numerical (BEM) estimation. Moreover, a force balance test is carried out on a single stationary blade for 16 angles of incidence, −6°≤α′≤30°, and three free stream velocities, 5, 7 and 9 m/s, and integral blade aerodynamic coefficients are determined. These experimental characteristics are intended to provide a useful basis for developing an alternative computational method to use integral blade experimental aerodynamic data to predict the power curve of the wind turbine in the transition zone between dynamic stall and fully stalled regimes.
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Kim, Young Dae, and Daniel De Kee. "Electrorheological Fluid Hysteresis." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-82355.

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Electrorheological (ER) fluids are suspensions of polarizable particles dispersed in insulating liquids. They exhibit a rapid and reversible transition from a liquid-like to a solid-like state upon the application of an electric field. The observed shear stress - shear rate hysteresis makes the precise control of the ER mechanical devices very difficult. Hysteresis behavior of TiO2 ER fluids were observed by varying particle concentration, electric field strength, maximum shear rate, and the time of hysteresis loop. In the absence of an electric field, the stress level of the up curve exceeds that of the down curve. The presence of an electric field, reverses this trend. The extent of hysteresis becomes more significant with increasing electric field strength, particle concentration, and maximum shear rate. Hysteresis behavior of TiO2 ER fluids seems to arise mainly due to the change of the particle structure during shearing. To describe the complex rheological behavior of ER fluids, a kinetic theory is presented. Model predictions show qualitative agreement with the experimental hysteresis data.
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Reports on the topic "W-Curve Theory of Transition"

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Wilkowski, G. M., D. Rudland, P. Mincer, B. Metrovich, and D. Rider. ASME-PVP05 Brittle-to-Ductile Fracture Initiation Transition Temperature for Old Linepipe w Surface-Crack. Pipeline Research Council International, Inc. (PRCI), 2005. http://dx.doi.org/10.55274/r0011772.

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Much work has been done to assess constraint effects on the crack-driving force for specimens and cracks in pipes. The material's transition temperature where the fracture process changes from ductile tearing to cleavage fracture at crack initiation is affected by the constraint conditions but is a material property that cannot be determined analytically. This paper presents a methodology to account for constraint effects to predict the lowest temperature where ductile fracture initiation occurs and relates that temperature back to Charpy impact data for X60 and lower grades, particularly for older vintage linepipe materials. The method involves a series of transition temperature shifts to account for thickness effects, strain-rate effects, and constraint effects to give a master curve of transition temperatures from Charpy data to through-wall-cracked or surface-cracked pipes (with various a/t values) under quasi-static loading. These transition temperature shifts were based on hundreds of pipe tests and thousands of specimen tests over several decades of work by numerous investigators. This method is being validated by examining 1927 and 1948 vintage linepipe steels. In addition, data have been developed on the 1927 vintage pipe material to assess the effect of the bluntness of a corrosion flaw on the lowest temperature where ductile fracture will still initiate under quasi-static loading. An additional transition temperature shift occurs as a function of the bluntness of the flaw.
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Tiku, Pussegoda, and Luffman. L52031 In-Situ Pipeline Mechanical Property Characterization. Pipeline Research Council International, Inc. (PRCI), 2003. http://dx.doi.org/10.55274/r0011133.

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The focus in the present study was to establish whether there is a reasonable correlation between the Charpy Vee Notch (CVN) toughness and the non-destructive Potential Difference (PD) measurements of ferritic-pearlitic steels having a range of CVN toughness values. Complete material characterization was carried out for six steels procured for this program. The characterization included chemical analysis, microstructural information, tensile properties and CVN transition curves. In addition, most of the data including the CVN transition curves were available for five suitable pipe line steels from a recent publication in the literature.
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Asenath-Smith, Emily, Emma Ambrogi, Lee Moores, Stephen Newman, and Jonathon Brame. Leveraging chemical actinometry and optical radiometry to reduce uncertainty in photochemical research. Engineer Research and Development Center (U.S.), 2021. http://dx.doi.org/10.21079/11681/42080.

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Subtle aspects of illumination sources and their characterization methods can introduce significant uncertainty into the data gathered from light-activated experiments, limiting their reproducibility and technology transition. Degradation kinetics of methyl orange (MO) and carbamazepine (CM) under illumination with TiO₂ were used as a case study for investigating the role of incident photon flux on photocatalytic degradation rates. Valerophenone and ferrioxalate actinometry were paired with optical radiometry in three different illumination systems: xenon arc (XE), tungsten halogen (W-H), and UV fluorescent (UV-F). Degradation rate constants for MO and CM varied similarly among the three light systems as k W-H &lt; kiv-F &lt; kXE, implying the same relative photon flux emission by each light. However, the apparent relative photon flux emitted by the different lights varied depending on the light characterization method. This discrepancy is shown to be caused by the spectral distribution present in light emission profiles, as well as absorption behavior of chemical actinometers and optical sensors. Data and calculations for the determination of photon flux from chemical and calibrated optical light characterization is presented, allowing us to interpret photo-degradation rate constants as a function of incident photon flux. This approach enabled the derivation of a calibrated ‘rate-flux’ metric for evaluating and translating data from photocatalysis studies.
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Wagner, D. Ry, Eliezer Lifschitz, and Steve A. Kay. Molecular Genetic Analysis of Flowering in Arabidopsis and Tomato. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7585198.bard.

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The primary objectives for the US lab included: the characterization of ELF3 transcription and translation; the creation and characterization of various transgenic lines that misexpress ELF3; defining genetic pathways related to ELF3 function regulating floral initiation in Arabidopsis; and the identification of genes that either interact with or are regulated by ELF3. Light quality, photoperiod, and temperature often act as important and, for some species, essential environmental cues for the initiation of flowering. However, there is relatively little information on the molecular mechanisms that directly regulate the developmental pathway from the reception of the inductive light signals to the onset of flowering and the initiation of floral meristems. The ELF3 gene was identified as possibly having a role in light-mediated floral regulation since elj3 mutants not only flower early, but exhibit light-dependent circadian defects. We began investigating ELF3's role in light signalling and flowering by cloning the ELF3 gene. ELF3 is a novel gene only present in plant species; however, there is an ELF3 homolog within Arabidopsis. The Arabidopsis elj3 mutation causes arrhythmic circadian output in continuous light; however, we show conclusively normal circadian function with no alteration of period length in elj3 mutants in dark conditions and that the light-dependent arrhythmia observed in elj3 mutants is pleiotropic on multiple outputs regardless of phase. Plants overexpressing ELF3 have an increased period length in constant light and flower late in long-days; furthermore, etiolated ELF3-overexpressing seedlings exhibit a decreased acute CAB2 response after a red light pulse, whereas the null mutant is hypersensitive to acute induction. This finding suggests that ELF3 negatively regulates light input to both the clock and its outputs. To determine whether ELF3's action is phase dependent, we examined clock resetting by light pulses and constructed phase response curves. Absence of ELF3 activity causes a significant alteration of the phase response curve during the subjective night, and overexpression of ELF3 results in decreased sensitivity to the resetting stimulus, suggesting that ELF3 antagonizes light input to the clock during the night. Indeed, the ELF3 protein interacts with the photoreceptor PHYB in the yeast two-hybrid assay and in vitro. The phase ofELF3 function correlates with its peak expression levels of transcript and protein in the subjective night. ELF3 action, therefore, represents a mechanism by which the oscillator modulates light resetting. Furthermore, flowering time is dependent upon proper expression ofELF3. Scientifically, we've made a big leap in the understanding of the circadian system and how it is coupled so tightly with light reception in terms of period length and clock resetting. Agriculturally, understanding more about the way in which the clock perceives and relays temporal information to pathways such as those involved in the floral transition can lead to increased crop yields by enabling plants to be grown in suboptimal conditions.
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