Journal articles: 'W-Curve Theory of Transition'

1

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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10

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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11

Rips, Ilya, and Eli Pollak. "Variational transition state theory for curve crossing processes: A uniform rate expression." Journal of Chemical Physics 103, no. 18 (1995): 7912–26. http://dx.doi.org/10.1063/1.470209.

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12

NICHOLSON, ANGUS F., and DALLAS C. KENNEDY. "ELECTROWEAK THEORY WITHOUT HIGGS BOSONS." International Journal of Modern Physics A 15, no. 10 (2000): 1497–519. http://dx.doi.org/10.1142/s0217751x00000677.

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A perturbative SU (2)L× U (1)Y electroweak theory containing W, Z, photon, ghost, lepton and quark fields, but no Higgs or other fields, gives masses to W, Z and the nonneutrino fermions by means of an unconventional choice for the unperturbed Lagrangian and a novel method of renormalization. The renormalization extends to all orders. The masses emerge on renormalization to one loop. To one loop the neutrinos are massless, the A↔Z transition drops out of the theory, the d quark is unstable and S matrix elements are independent of the gauge parameter ξ.

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13

Lucco Castello, Federico, and Panagiotis Tolias. "Theoretical Estimate of the Glass Transition Line of Yukawa One-Component Plasmas." Molecules 26, no. 3 (2021): 669. http://dx.doi.org/10.3390/molecules26030669.

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The mode coupling theory of supercooled liquids is combined with advanced closures to the integral equation theory of liquids in order to estimate the glass transition line of Yukawa one-component plasmas from the unscreened Coulomb limit up to the strong screening regime. The present predictions constitute a major improvement over the current literature predictions. The calculations confirm the validity of an existing analytical parameterization of the glass transition line. It is verified that the glass transition line is an approximate isomorphic curve and the value of the corresponding reduced excess entropy is estimated. Capitalizing on the isomorphic nature of the glass transition line, two structural vitrification indicators are identified that allow a rough estimate of the glass transition point only through simple curve metrics of the static properties of supercooled liquids. The vitrification indicators are demonstrated to be quasi-universal by an investigation of hard sphere and inverse power law supercooled liquids. The straightforward extension of the present results to bi-Yukawa systems is also discussed.

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14

Wright, Paul E. "Two parallel processors with coupled inputs." Advances in Applied Probability 24, no. 4 (1992): 986–1007. http://dx.doi.org/10.2307/1427722.

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We consider the double queue arising from a system consisting of two processors serving three job streams generated by independent Poisson sources. The central job stream of rate v consists of jobs which place resource demands on both processors, which are handled separately by each processor once the request is made. In addition, the first processor receives background work at a rate of λwhile the second receives similar tasks at a rate η. Each processor has exponentially distributed service times with rates α and β respectively. A functional equation is found for P(z, w), the generating function of the joint queue-length distribution, which leads to a relation between P(z, 0) and P(0, w) in the region |z|, |w| < 1 of a complex algebraic curve associated with the problem. The curve is parametrized by elliptic functions z(ξ) and w(ξ) and the relation between Ρ (z(ξ), 0) and P(0, w(ξ)) persists on their analytic continuation as elliptic functions in the ξ-plane. This leads to their eventual determination by an appeal to the theory of elliptic functions. From this determination we obtain asymptotic limit laws for the expectations of the mean number of jobs in each queue conditioned on the other, as the number of jobs in both processors tends to∞. Transitions are observed in the asymptotic behavior of these quantities as one crosses various boundaries in the parameter space. An interpretation of these results via the theory of large deviations is presented.

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15

Wright, Paul E. "Two parallel processors with coupled inputs." Advances in Applied Probability 24, no. 04 (1992): 986–1007. http://dx.doi.org/10.1017/s0001867800025040.

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We consider the double queue arising from a system consisting of two processors serving three job streams generated by independent Poisson sources. The central job stream of rate v consists of jobs which place resource demands on both processors, which are handled separately by each processor once the request is made. In addition, the first processor receives background work at a rate of λwhile the second receives similar tasks at a rate η. Each processor has exponentially distributed service times with rates α and β respectively. A functional equation is found for P(z, w), the generating function of the joint queue-length distribution, which leads to a relation between P(z, 0) and P(0, w) in the region |z|, |w| &lt; 1 of a complex algebraic curve associated with the problem. The curve is parametrized by elliptic functions z(ξ) and w(ξ) and the relation between Ρ (z(ξ), 0) and P(0, w(ξ)) persists on their analytic continuation as elliptic functions in the ξ-plane. This leads to their eventual determination by an appeal to the theory of elliptic functions. From this determination we obtain asymptotic limit laws for the expectations of the mean number of jobs in each queue conditioned on the other, as the number of jobs in both processors tends to∞. Transitions are observed in the asymptotic behavior of these quantities as one crosses various boundaries in the parameter space. An interpretation of these results via the theory of large deviations is presented.

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BILGE, AYSE HUMEYRA, and ONDER PEKCAN. "A MATHEMATICAL DESCRIPTION OF THE CRITICAL POINT IN PHASE TRANSITIONS." International Journal of Modern Physics C 24, no. 10 (2013): 1350065. http://dx.doi.org/10.1142/s0129183113500654.

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Let y(x) be a smooth sigmoidal curve, y(n) be its nth derivative and {xm,i} and {xa,i}, i = 1,2,…, be the set of points where respectively the derivatives of odd and even order reach their extreme values. We argue that if the sigmoidal curve y(x) represents a phase transition, then the sequences {xm,i} and {xa,i} are both convergent and they have a common limit xc that we characterize as the critical point of the phase transition. In this study, we examine the logistic growth curve and the Susceptible-Infected-Removed (SIR) epidemic model as typical examples of symmetrical and asymmetrical transition curves. Numerical computations indicate that the critical point of the logistic growth curve that is symmetrical about the point (x0, y0) is always the point (x0, y0) but the critical point of the asymmetrical SIR model depends on the system parameters. We use the description of the sol–gel phase transition of polyacrylamide-sodium alginate (SA) composite (with low SA concentrations) in terms of the SIR epidemic model, to compare the location of the critical point as described above with the "gel point" determined by independent experiments. We show that the critical point tc is located in between the zero of the third derivative ta and the inflection point tm of the transition curve and as the strength of activation (measured by the parameter k/η of the SIR model) increases, the phase transition occurs earlier in time and the critical point, tc, moves toward ta.

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Biaggne, Austin, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, and Lan Li. "Substituent Effects on the Solubility and Electronic Properties of the Cyanine Dye Cy5: Density Functional and Time-Dependent Density Functional Theory Calculations." Molecules 26, no. 3 (2021): 524. http://dx.doi.org/10.3390/molecules26030524.

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The aggregation ability and exciton dynamics of dyes are largely affected by properties of the dye monomers. To facilitate aggregation and improve excitonic function, dyes can be engineered with substituents to exhibit optimal key properties, such as hydrophobicity, static dipole moment differences, and transition dipole moments. To determine how electron donating (D) and electron withdrawing (W) substituents impact the solvation, static dipole moments, and transition dipole moments of the pentamethine indocyanine dye Cy5, density functional theory (DFT) and time-dependent (TD-) DFT calculations were performed. The inclusion of substituents had large effects on the solvation energy of Cy5, with pairs of withdrawing substituents (W-W pairs) exhibiting the most negative solvation energies, suggesting dyes with W-W pairs are more soluble than others. With respect to pristine Cy5, the transition dipole moment was relatively unaffected upon substitution while numerous W-W pairs and pairs of donating and withdrawing substituents (D-W pairs) enhanced the static dipole difference. The increase in static dipole difference was correlated with an increase in the magnitude of the sum of the Hammett constants of the substituents on the dye. The results of this study provide insight into how specific substituents affect Cy5 monomers and which pairs can be used to engineer dyes with desired properties.

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Liu, Yu, Xiaobo Feng, Yonggang Qin, and Qianjin Wang. "Width Dependent Two-Photon Absorption in Monolayer Black Phosphorus Nanoribbons." Applied Sciences 9, no. 10 (2019): 2014. http://dx.doi.org/10.3390/app9102014.

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Black phosphorus nanoribbons (BPNs) might offer alternatives to narrow-gap compound semiconductors for tunable optoelectronics in infrared region. In this work we present a quantum perturbation theory on two-photon absorption (TPA) in monolayer armchair-edged black phosphorus nanoribbons (acBPNs) employing the reduced two-band model within the long-wavelength BP Hamiltonian. The matrix elements for one-photon transition have been derived and the TPA spectrum associate with intra conduction band transition and inter band transition have been drawn. The calculations predict that the TPA coefficient in acBPNs is in the magnitude of 10−6 m/W in visible region, which is 4 orders higher than the conventional semiconductor quantum dots. And in infrared region, there is a giant TPA coefficient, which is mainly contributed from intra band transitions and can reach up to10−1 m/W. The TPA peaks can be tuned both by the width of BPNs and the electron relaxation energy.

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TONG, NING-HUA, and SHUN-QING SHEN. "LOW TEMPERATURE PROPERTIES OF THE MOTT–HUBBARD TRANSITION." Modern Physics Letters B 15, no. 27 (2001): 1249–58. http://dx.doi.org/10.1142/s0217984901003123.

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The unanalytical feature of the Mott–Hubbard metal-insulator transition in infinite dimensions is studied by using a modified self-consistency scheme in the framework of dynamical mean-field theory. For a specific low temperature T=0.0025W (W: half bandwidth), the "Z"-shaped or "S"-shaped curves for double occupancy D, energy per lattice site E, and the quasi-particle weight Z are obtained as functions of U. Direct observation shows that the Fermi-liquid phase changes to the insulating phase through a non-Fermi-liquid phase at the unstable level. Based on our results, a scenario of zero temperature MIT is proposed. The phase diagram for MIT on the T–D plane is also presented.

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Bambach, Markus. "Comparison of the Identifiability of Flow Curves from the Hydraulic Bulge Test by Membrane Theory and Inverse Analysis." Key Engineering Materials 473 (March 2011): 360–67. http://dx.doi.org/10.4028/www.scientific.net/kem.473.360.

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In the hydraulic bulge test, flow curves are determined by applying a hydrostatic pressure to one side of a clamped sheet metal specimen, which bulges freely into a circular cavity under the pressure. The pressure and various data such as bulge height, curvature and equivalent strain at the pole are recorded and used to calculate the flow curve of the specimen material using analytical equations based on membrane theory. In the determination of the flow curve, the elastic behavior of the specimen, the elastic-plastic transition and bending effects are neglected, and the flow curves calculated this way are affected by these simplifications. An alternative to this procedure is an inverse analysis, which proceeds by searching for a flow curve that minimizes the difference between computed and measured data, e.g. bulge height vs. pressure. An inverse analysis based on a finite element model takes into account elastic and bending effects but since it involves the solution of an optimization problem, it is not clear whether it yields more accurate results than membrane theory. The objective of this paper is to compare the ‘identifiability’ of a given flow curve from the bulge test by direct identification based on membrane theory and by inverse analysis with different objective functions to be minimized. Using a re-identification procedure, it is shown that an inverse analysis can improve the results of the direct identification if a suitable objective function is chosen.

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Suleimenov, I. E., S. T. Baipakbayeva, G. A. Mun, D. B. Kaldybekov, B. B. Yermukhambetova, and A. S. Bakirov. "Analysis of Phase Transitions of Thermoresponsive Polymer Based on N-Vinylcaprolactam and 2-Hydroxyethyl Acrylate in Solutions from the Information Theory Point of View." Eurasian Chemico-Technological Journal 26, no. 2 (2024): 67–73. http://dx.doi.org/10.18321/ectj1609.

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A new method for analyzing phase transitions in solutions of thermoresponsive polymers is proposed, based on determining the amount of information contained in the curve describing the phase transition. The method is based on the use of an analogy with the Nyquist-Shannon-Kotelnikov theorem, which allows us to bring the analysis of a continuous function to the analysis of its values at discrete points, as well as the results of studies of slowly changing signals from the point of view of modern information theory. This analogy allows us to determine the minimum number of parameters that describe the phase transition. The proposed method was tested using the example of phase transitions in solutions of thermoresponsive copolymers of N-vinylcaprolactam with 2-hydroxyethyl acrylate of various compositions. The effectiveness of this method has been demonstrated; in particular, it has been shown that the number of parameters that describe the phase transition in this case does not exceed four. The possibilities of using the proposed method for constructing a classification of phase transitions in solutions of stimulus-sensitive polymers are discussed.

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Jiang, Chao, Yongfeng Zhang, Yipeng Gao, and Jian Gan. "Ab initio theory of noble gas atoms in bcc transition metals." Physical Chemistry Chemical Physics 20, no. 25 (2018): 17048–58. http://dx.doi.org/10.1039/c8cp01817k.

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Systematic ab initio calculations based on density functional theory have been performed to gain fundamental understanding of the interactions between noble gas atoms (He, Ne, Ar and Kr) and bcc transition metals in groups 5B (V, Nb and Ta), 6B (Cr, Mo and W) and 8B (Fe).

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Peredo-Ortiz, Ricardo, Pablo F. Zubieta Rico, Ernesto C. Cortés-Morales, et al. "Non-equilibrium relaxation and aging in the dynamics of a dipolar fluid quenched towards the glass transition." Journal of Physics: Condensed Matter 34, no. 8 (2021): 084003. http://dx.doi.org/10.1088/1361-648x/ac3b75.

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Abstract The recently developed non-equilibrium self-consistent generalized Langevin equation theory of the dynamics of liquids of non-spherically interacting particles [2016 J. Phys. Chem. B 120 7975] is applied to the description of the irreversible relaxation of a thermally and mechanically quenched dipolar fluid. Specifically, we consider a dipolar hard-sphere liquid quenched (at t w = 0) from full equilibrium conditions towards different ergodic–non-ergodic transitions. Qualitatively different scenarios are predicted by the theory for the time evolution of the system after the quench (t w > 0), that depend on both the kind of transition approached and the specific features of the protocol of preparation. Each of these scenarios is characterized by the kinetics displayed by a set of structural correlations, and also by the development of two characteristic times describing the relaxation of the translational and rotational dynamics, allowing us to highlight the crossover from equilibration to aging in the system and leading to the prediction of different underlying mechanisms and relaxation laws for the dynamics at each of the glass transitions explored.

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Chao, Yu-Huan, Shou-Yu Wang, and Shuh-Jen Sheu. "Integrative review of breast cancer survivors’ transition experience and transitional care: dialog with transition theory perspectives." Breast Cancer 27, no. 5 (2020): 810–18. http://dx.doi.org/10.1007/s12282-020-01097-w.

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Ptaszyńska, Barbara. "Interwencjonizm państwa w Polsce oraz w krajach UE i OECD." Wiadomości Statystyczne. The Polish Statistician 2010, no. 3 (2010): 68–75. http://dx.doi.org/10.59139/ws.2010.03.5.

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Characteristics of state interventionism according to economic theory as well as an analysis of the state involvement into economy on the income redistribution rate basis are presented in the article. The survey included years 1991–2007. The state intervention level into Polish economy was high, similar to the EU countries, in transition period. This resulted from characteristics of changes followed in Poland. Due to the disadvantageous structure in public expenditures as well as economic development level of the country, the level is still high. Social assistance for natural persons and the maintenance of public sector units make more than 80 percent of public expenditures. Economic task subsidies and property expenditures make only 10 percent of all sector expenditures.

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Muzyk, M., and K. J. Kurzydłowski. "Generalised stacking fault energies of copper alloys - density functional theory calculations." Journal of Mining and Metallurgy, Section B: Metallurgy 55, no. 2 (2019): 271–82. http://dx.doi.org/10.2298/jmmb181128020m.

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Generalised stacking fault energies of copper alloys have been calculated using density functional theory. Stacking fault energy of copper alloys is correlated with the d?electrons number of transition metal alloying element. The tendency to twiningis also modified by the presence of alloying element in the deformation plane. The results suggest that Cu ?transition metal alloys with such elements as Cr, Mo, W, Mn, Re are expected to exhibit great work hardening rate due to the tendency to emission of the partial dislocations.

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Turulski, Jan, Barbara Pezler, and Jan Niedzielski. "Classical transition state theory for the ion—linear quadrupole capture." Chemical Physics 166, no. 1-2 (1992): 115–21. http://dx.doi.org/10.1016/0301-0104(92)87011-w.

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LUQI, LIN ZHANG, and MIKE SABOE. "THE DYNAMICAL MODELS FOR SOFTWARE TECHNOLOGY TRANSITION." International Journal of Software Engineering and Knowledge Engineering 14, no. 02 (2004): 179–205. http://dx.doi.org/10.1142/s0218194004001592.

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Currently, systematic techniques for assessing macro mechanisms for transferring software engineering technologies are non-existent. This leads to inefficient allocation of research resources and increased risk to software technology intensive programs. Consequently, software technology transition today is an ill-defined and non-repeatable, inefficient process for bringing advanced software engineering technologies to market. This paper develops two dynamical models of a software technology transition from both macroscopic and microscopic views. The models are developed utilizing information theory, communication theory, chaos control theory, and learning curve principles. The combination of those scientifically sound mechanisms provides a basis for assessing, and/or prescribing a portfolio of technologies and the implementing macro infrastructure. This provides the theoretical framework for a practical method for a program manager to establish a high capacity transition channel, which accelerates technology maturation and insertion. Experiments based on very large number of data have been performed. Data samples assess the following technologies: software engineering, software technology transfer, Ada, Java, abstract data types, rate monotonic analysis, cost models, software standards, and software work breakdown structures.

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Wetherington, Ronald K. ": Culture and Reproduction: An Anthropological Critique of Demographic Transition Theory . W. Penn Handwerker." American Anthropologist 89, no. 3 (1987): 757–58. http://dx.doi.org/10.1525/aa.1987.89.3.02a00580.

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Wang, Ying, He Wang, Shengli Zhang, Zhiwei Yang, Xuguang Shi, and Lei Zhang. "Exploration of the Character Representation of DNA Chiral Conformations and Deformations via a Curved Surface Discrete Frenet Frame." International Journal of Molecular Sciences 25, no. 1 (2023): 4. http://dx.doi.org/10.3390/ijms25010004.

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While undergoing structural deformation, DNA experiences changes in the interactions between its internal base pairs, presenting challenges to conventional elastic methods. To address this, we propose the Discrete Critical State (DCS) model in this paper. This model combines surface discrete frame theory with gauge theory and Landau phase transition theory to investigate DNA’s structural deformation, phase transitions, and chirality. Notably, the DCS model considers both the internal interactions within DNA and formulates an overall equation using unified physical and geometric parameters. By employing the discrete frame, we derive the evolution of physical quantities along the helical axis of DNA, including geodesic curvature, geodesic torsion, and others. Our findings indicate that B-DNA has a significantly lower free energy density compared to Z-DNA, which is in agreement with experimental observations. This research reveals that the direction of base pairs is primarily governed by the geodesic curve within the helical plane, aligning closely with the orientation of the base pairs. Moreover, the geodesic curve has a profound influence on the arrangement of base pairs at the microscopic level and effectively regulates the configuration and geometry of DNA through macroscopic-level free energy considerations.

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Zhu, Chaoyuan, and Hiroki Nakamura. "Theory of nonadiabatic transition for general two‐state curve crossing problems. II. Landau–Zener case." Journal of Chemical Physics 102, no. 19 (1995): 7448–61. http://dx.doi.org/10.1063/1.469057.

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Zhu, Chaoyuan, and Hiroki Nakamura. "Theory of nonadiabatic transition for general two‐state curve crossing problems. I. Nonadiabatic tunneling case." Journal of Chemical Physics 101, no. 12 (1994): 10630–47. http://dx.doi.org/10.1063/1.467877.

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Fan, Yourong, Xinhua Wang, Zhe Hu, and Kai Zhang. "Nonlinear modeling and transition corridor calculation of a tiltrotor without cyclic pitch." MATEC Web of Conferences 355 (2022): 01022. http://dx.doi.org/10.1051/matecconf/202235501022.

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In order to solve the problem of rotor airflow interference to the wing of tiltrotor UAV, the lift and drag in the slipstream area and the free flow area were calculated respectively according to the hydrodynamics theory and CFD simulation. The longitudinal nonlinear dynamics model of tiltrotor UAV is established by Newton-Euler method. In order to solve the problem that the lift and thrust are difficult to balance the body gravity in the transition flight mode, a method for calculating the transition corridor of a tiltrotor UAV without cyclic pitch is proposed. The boundary of the transition corridor is restricted by the Angle of attack of the wing and the thrust of the rotor. Considering the requirements of UAV cruise speed, flight safety and minimum energy consumption, the optimal transition curve is selected. The result show that the designed transition curve can ensure that the lift and the rotor thrust can balance the gravity completely and the Angle of attack is in a reasonable range, and the rotor force has enough margin of safety.

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Wu, Yu Rong, Wang Yu Hu, and Long Shan Xu. "Site Preference and Elastic Properties of 5d Transition Metals in Ductility YAg Alloys." Advanced Materials Research 472-475 (February 2012): 1397–401. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.1397.

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First-principles supercell calculations, which are based on density functional theory, were performed to study the site preference behavior and elastic properties of 5d (Hf-Au) transition-metal elements in B2 ductility YAg alloy. It is found that all alloying elements Hf, Ta, W, Re, Os, Ir, Pt and Au occupy the Y sub-lattice. Micro-alloying transition metals W, Re, Os, Ir and Pt decrease the lattice parameters of Y8Ag8 except Hf, Ta and Au, among which Y8Ag7Hf shows the largest variance. Furthermore, the calculated elastic constants show that Hf, Ta, W, Re, Os, Pt and Au improve the ductility of YAg alloy, and Y8Ag7Hf presents the most ductility among these alloy, while Ir transforms ductile into brittle for YAg alloy. In addition, Os alloying element increases the hardness of YAg alloy.

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Parlinski, K., and Y. Kawazoe. "Domain pattern formation in ferroelastic Pb3(PO4)2 by computer simulation." Journal of Materials Research 12, no. 9 (1997): 2366–73. http://dx.doi.org/10.1557/jmr.1997.0313.

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A model of lead phosphate, which describes the rhombohedral-monoclinic phase transition, is used to form domain patterns in the annealing process. The obtained domain structures show W and W′ types of domain walls in agreement with the stress-free laws proposed in Sapriel's theory. The observed W domain walls are parallel to the ternary symmetry axis, while the W′ ones are tilted with respect to the same axis. The antiphase domain walls take no preferential orientations, and remain parallel to the ternary axis. The calculated density of the potential energy of the domain wall of type W is estimated to be Edw = 49 K/Å2 at T = 300 K.

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Yang, D. C. H., and Jui-Jen Chou. "Automatic Generation of Piecewise Constant Speed Motion with Smooth Transition for Multi-Axis Machines." Journal of Mechanical Design 116, no. 2 (1994): 581–86. http://dx.doi.org/10.1115/1.2919417.

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This paper presents a general theory on generating a smooth motion profile for the coordinated motion of five-axes CNC/CMM machines. Motion with constat speed is important and required in many manufacturing processes, such as milling, welding, finishing, and painting. In this paper, a piecewise constant speed profile is constructed by a sequence of Hermite curves to form a composite Hermite curve in parametric domain. Given the continuity of acceleration in our proposed speed profile, it generates relatively better product quality than traditional techniques. We also provide a method for the feasibility study of manufacturing capability in terms of the given machine, the desired path, and the assigned speed. We consider machine dynamics, actuator limitation, path geometry, jerk constraints, and motion kinematics.

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LI, QIANG, FANG-QIU ZU, XIAN-FEN LI, and YUN XI. "THE ELECTRICAL RESISTIVITY OF LIQUID Pb-Bi ALLOY." Modern Physics Letters B 20, no. 04 (2006): 151–58. http://dx.doi.org/10.1142/s0217984906009037.

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Different from the conventional liquid theory, experimental evidence suggests that there might be discontinuous liquid-liquid (L-L) structure transitions for some alloys. By the resistivity experiments, it is assumed that a temperature-induced L-L structure transition might occur in liquid lead-bismuth ( PbBi ) alloy. The electrical resistivity of four compositions for PbBi alloy versus temperature was precisely measured in our experiment. It was found that the resistivity increases linearly with temperature rising in a certain range of temperature above the melting point. During subsequent calefaction, the results obviously showed that a turning point appears in the resistivity-temperature (R-T) curve for every composition at a certain temperature. The turning temperature depends on composition. It can be considered that there is L-L structure transition in some regions of high temperature for PbBi alloy.

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Ramaswamy, Meera, Itay Griniasty, Danilo B. Liarte, et al. "Universal scaling of shear thickening transitions." Journal of Rheology 67, no. 6 (2023): 1189–97. http://dx.doi.org/10.1122/8.0000697.

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Nearly, all dense suspensions undergo dramatic and abrupt thickening transitions in their flow behavior when sheared at high stresses. Such transitions occur when the dominant interactions between the suspended particles shift from hydrodynamic to frictional. Here, we interpret abrupt shear thickening as a precursor to a rigidity transition and give a complete theory of the viscosity in terms of a universal crossover scaling function from the frictionless jamming point to a rigidity transition associated with friction, anisotropy, and shear. Strikingly, we find experimentally that for two different systems—cornstarch in glycerol and silica spheres in glycerol—the viscosity can be collapsed onto a single universal curve over a wide range of stresses and volume fractions. The collapse reveals two separate scaling regimes due to a crossover between frictionless isotropic jamming and frictional shear jamming, with different critical exponents. The material-specific behavior due to the microscale particle interactions is incorporated into a scaling variable governing the proximity to shear jamming, that depends on both stress and volume fraction. This reformulation opens the door to importing the vast theoretical machinery developed to understand equilibrium critical phenomena to elucidate fundamental physical aspects of the shear thickening transition.

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Lan, Shan-Quan, Gu-Qiang Li, Jie-Xiong Mo, and Xiao-Bao Xu. "New Phase Transition Related to the Black Hole’s Topological Charge." Advances in High Energy Physics 2019 (January 2, 2019): 1–8. http://dx.doi.org/10.1155/2019/8270265.

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The topological charge ϵ of AdS black hole is introduced by Tian et al. in their papers, where a complete thermodynamic first law is obtained. In this paper, we investigate a new phase transition related to the topological charge in Einstein-Maxwell theory. Firstly, we derive the explicit solutions corresponding to the divergence of specific heat Cϵ and determine the phase transition critical point. Secondly, the T-r curve and T-S curve are investigated and they exhibit an interesting van der Waals system’s behavior. Critical physical quantities are also obtained which are consistent with those derived from the specific heat analysis. Thirdly, a van der Waals system’s swallow tail behavior is observed when ϵ>ϵc in the F-T graph. What is more, the analytic phase transition coexistence lines are obtained by using the Maxwell equal area law and free energy analysis, the results of which are consistent with each other.

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Mlinarič, Franjo, Grygorii Kravchenko, and Boštjan Brezovnik. "Harmonising Agency Theory and Sustainable Economic Paradigm – Improving Market Efficiency by Smart Regulation." Studia Iuridica Lublinensia 33, no. 1 (2024): 143–57. http://dx.doi.org/10.17951/sil.2024.33.1.143-157.

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We examined the intricate dynamics of agency theory within the framework of sustainable economic transition, which is incredibly capital intensive. Recognizing the gravity of sustainable transition, we address the challenges posed by the Second Order Agency Problem (SOAP) and market failures related to public goods. The research explores the subtle shift towards dominant credence goods and services, emphasizing the need for standardized non-financial information fuelling market’s efficiency. The primary aim is to bridge the gap between classical agency theory and modern sustainable economics applications. Our findings introduce an innovative Regulation Curve Model (RCM) presenting a fresh perspective on the cost-benefit dynamics of regulation. This study’s scope is international, with a specific focus on case studies from Poland and Slovenia. Our results from the RCM concept and from the sustainable strategy scoring model offer significant cognitive value for both academic science and practical policymaking. The research holds potential for guiding future sustainable policies and offers insights for nations navigating the complexities of economic transition.

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Matsubara, Masahiko, Rolando Saniz, Bart Partoens, and Dirk Lamoen. "Doping anatase TiO2 with group V-b and VI-b transition metal atoms: a hybrid functional first-principles study." Physical Chemistry Chemical Physics 19, no. 3 (2017): 1945–52. http://dx.doi.org/10.1039/c6cp06882k.

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We investigate the role of transition metal atoms of group V-b (V, Nb, and Ta) and VI-b (Cr, Mo, and W) as n- or p-type dopants in anatase TiO<sub>2</sub> using thermodynamic principles and density functional theory with the HSE06 hybrid functional.

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Castillo, Wilson, Ricardo Gallardo-Sepúlveda, Edison Atencio, Ricardo Moffat, and Omar Nuñez. "Numerical Modeling of One-Dimensional Consolidation Theory in Saturated and Unsaturated Tailings Using the Soft Soil and Hardening Soil Constitutive Models." Applied Sciences 15, no. 6 (2025): 3111. https://doi.org/10.3390/app15063111.

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This study focuses on the numerical modeling of one-dimensional consolidation of filtered copper tailings under saturated and unsaturated conditions using Plaxis2D®. The modeling is based on 1D consolidation curves under saturated conditions and controlled matric suction. The Soft Soil and Hardening Soil constitutive models were employed, incorporating the soil–water characteristic curve (SWCC) to capture hydro-mechanical behavior and volumetric strain. The modeling strategy replicates the loading and drainage conditions of the experimental tests, using a single set of soil parameters to represent the transition from unsaturated to saturated conditions. Axisymmetric simulations were conducted to replicate the geometry of the experimental specimen, considering initial saturation degrees of 60%, 80%, and 99%, followed by the application of vertical stresses ranging from 10 to 3200 kPa. The results demonstrate that the proposed modeling approach accurately represents the compressibility curve for both constitutive models across different saturation levels. This provides flexibility for conducting numerical analyses tailored to specific soil conditions and geotechnical design requirements. Furthermore, modeling allowed for the evaluation of excess pore pressures and their dissipation time under both saturated and unsaturated conditions.

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Radtke, M., and A. Ignaszak. "Classical group theory adapted to the mechanism of Pt3Ni nanoparticle growth: the role of W(CO)6 as the “shape-controlling” agent." Physical Chemistry Chemical Physics 18, no. 1 (2016): 75–78. http://dx.doi.org/10.1039/c5cp05060j.

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Girtler, Jerzy. "Limiting Distribution of the Three-State Semi-Markov Model of Technical State Transitions of Ship Power Plant Machines and its Applicability in Operational Decision-Making." Polish Maritime Research 27, no. 2 (2020): 136–44. http://dx.doi.org/10.2478/pomr-2020-0035.

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AbstractThe article presents the three-state semi-Markov model of the process {W(t): t ≥ 0} of state transitions of a ship power plant machine, with the following interpretation of these states: s1 – state of full serviceability, s2 – state of partial serviceability, and s3 – state of unserviceability. These states are precisely defined for the ship main engine (ME). A hypothesis is proposed which explains the possibility of application of this model to examine models of real state transitions of ship power plant machines. Empirical data concerning ME were used for calculating limiting probabilities for the process {W(t): t ≥ 0}. The applicability of these probabilities in decision making with the assistance of the Bayesian statistical theory is demonstrated. The probabilities were calculated using a procedure included in the computational software MATHEMATICA, taking into consideration the fact that the random variables representing state transition times of the process {W(t): t ≥ 0} have gamma distributions. The usefulness of the Bayesian statistical theory in operational decision-making concerning ship power plants is shown using a decision dendrite which maps ME states and consequences of particular decisions, thus making it possible to choose between the following two decisions: d1 – first perform a relevant preventive service of the engine to restore its state and then perform the commissioned task within the time limit determined by the customer, and d2 – omit the preventive service and start performing the commissioned task.

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45

Sato, S., S. Doi, and T. Nomura. "Bonhoeffer-van der Pol Oscillator Model of the Sino-Atrial Node: A Possible Mechanism of Heart Rate Regulation." Methods of Information in Medicine 33, no. 01 (1994): 116–19. http://dx.doi.org/10.1055/s-0038-1634966.

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Abstract:A Bonhoeffer-van der Pol equation with a stable limit cycle is proposed as a model of the pacemaker in the sino-atrial node to exptain heart rate regulation. Standard tools, such as the phase transition curve in nonlinear dynamic system theory, are used to analyze the model and results are compared with other studies on experiments with dogs.

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TEETER, G., and J. L. ERSKINE. "STUDIES OF CLEAN METAL SURFACE RELAXATION EXPERIMENT–THEORY DISCREPANCIES." Surface Review and Letters 06, no. 05 (1999): 813–17. http://dx.doi.org/10.1142/s0218625x99000846.

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A series of Low-Energy Electron Diffraction Intensity vs. Voltage (LEED I–V) measurements for Rh(001), W(110) and Ti(0001) have been undertaken in order to help resolve discrepancies between experiment and theory for the surface relaxations of certain transition metals. LEED measurements and analysis indicate the following results for the change of first (d12) and second (d23) interlayer spacings, relative to the bulk interlayer spacing d0: for Rh(001), Δ d12/d0=-1.4± 1.4% and Δ d23/d0=-0.6± 1.4%; for W(110), Δ d12/d0=-3.0± 1.3% and Δ d23/d0=+0.2± 1.3%; and for Ti(0001), Δ d12/d0=-4.9± 1.0% and Δ d23/d0=+1.4± 1.0%. In each case, the new measurements help to resolve the experiment–theory surface relaxation discrepancies. In addition, two of these surfaces [W(110) and Ti(0001)] show substantial contractions in the first interlayer spacing, d12. Large relaxations for close-packed surfaces lend support to the promotion–hybridization picture of surface relaxation put forth recently by P. J. Feibelman [P. J. Feibelman, Phys. Rev.B53, 13740 (1996).] In addition to making new experimental determinations of surface relaxations, a secondary goal of this work is to characterize sources of error associated with LEED I–V methodology that have traditionally not been fully appreciated.

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Keshavarzi, Ezat, Mahsa Abareghi, and Abbas Helmi. "Curvature dependence of the camel-bell curve transition on the capacitance curve of spherical electric double-layer in porous electrodes: Density Functional Theory." Electrochimica Acta 313 (August 2019): 303–10. http://dx.doi.org/10.1016/j.electacta.2019.05.038.

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Zibouche, Nourdine, Pier Philipsen, Thomas Heine, and Agnieszka Kuc. "Electron transport in MoWSeS monolayers in the presence of an external electric field." Phys. Chem. Chem. Phys. 16, no. 23 (2014): 11251–55. http://dx.doi.org/10.1039/c4cp00966e.

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The influence of an external electric field on single-layer transition-metal dichalcogenides TX<sub>2</sub> with T = Mo, W and X = S, Se (MoWSeS) has been investigated by means of density-functional theory within two-dimensional periodic boundary conditions under consideration of relativistic effects including the spin–orbit interactions.

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HAN, W. K., S. C. YING, and T. ALA-NISSILA. "ANOMALOUS DIFFUSION NEAR STRUCTURAL PHASE TRANSITIONS." Modern Physics Letters B 06, no. 18 (1992): 1099–103. http://dx.doi.org/10.1142/s0217984992001952.

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Using a recently developed microscopic theory of diffusion for a particle coupled to an inhomogeneous medium, it has been shown that in the case of a structural phase transition with a diverging central peak, a diffusion anomaly occurs. We review results of model calculations demonstrating this anomaly on the W(100) surface, as well as discuss other physical systems where analogous phenomena may be observed.

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Ivády, Viktor, Bálint Somogyi, Viktor Zólyomi, et al. "Transition Metal Defects in Cubic and Hexagonal Polytypes of SiC: Site Selection, Magnetic and Optical Properties from Ab Initio Calculations." Materials Science Forum 717-720 (May 2012): 205–10. http://dx.doi.org/10.4028/www.scientific.net/msf.717-720.205.

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Relatively little is known about the transition metal defects in silicon carbide (SiC). In this study we applied highly convergent and sophisticated density functional theory (DFT) based methods to investigate important transition metal impurities including titanium (Ti), vanadium (V), niobium (Nb), chromium (Cr), molybdenum (Mo) and tungsten (W) in cubic 3C and hexagonal 4H and 6H polytypes of SiC. We found two classes among the considered transition metal impurities: Ti, V and Cr clearly prefer the Si-substituting configuration while W, Nb, and Mo may fractionally form a complex with carbon vacancy in hexagonal SiC even under thermal equilibrium. If the metal impurity is implanted into SiC or when many carbon impurities exist during the growth of SiC then complex formation between Si-substituting metal impurity and the carbon vacancy should be considered. This complex pair configuration exclusively prefers the hexagonal-hexagonal sites in hexagonal polytypes and may be absent in cubic polytype. We also studied transition metal doped nano 3C-SiC crystals in order to check the effect of the crystal field on the d-orbitals of the metal impurity.

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

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