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There was an extensive epistemic community in historical East Asia that was central to the creation and dissemination of regional civilization that flowed mainly from China outwards, from core to periphery. This epistemic community was composed of Buddhist monks and Confucian scholars. They studied at Buddhist temples and Confucian academies, wrote in a common Chinese language using common styles, and made up the bulk of government officials in each country. These scholar-officials were also the ones who staffed diplomatic missions to other countries. This chapter will discuss in detail the flows of monks and literati between the various countries, and trace the influence of this transnational scholarly and religious community on the evolution of societies – as well as state formation – throughout the region.
The mathematical foundations of transport properties are analyzed in detail in several Hamiltonian dynamical models. Deterministic diffusion is studied in the multibaker map and the Lorentz gases where a point particle moves in a two-dimensional lattice of hard disks or Yukawa potentials. In these chaotic models, the diffusive modes are constructed as the eigenmodes of the Liouvillian dynamics associated with Pollicott–Ruelle resonances. These eigenmodes are distributions with a fractal cumulative function. As a consequence of this fractal character, the entropy production calculated by coarse graining has the expression expected for diffusion in nonequilibrium thermodynamics. Furthermore, Fourier’s law for heat conduction is shown to hold in many-particle billiard models, where heat conductivity can be evaluated with very high accuracy at a conductor-insulator transition. Finally, mechanothermal coupling is illustrated with models for motors propelled by a temperature difference.
The dynamic evolution of a classic molecular system is first introduced formally via Liouville equation. Then, single-particle time correlation functions and their general properties (like short and long time limits) for orientational correlation functions (OCF) in liquid crystals are discussed and translational and orientational diffusion coefficients are introduced. The link between OCFs, obtainable from computer simulations, and experiments is established with Linear Response theory and examples from dielectric relaxation, ionic and thermal conductivity, viscosities are presented, with reference to the literature. The rotational diffusion equation in an anisotropic fluid, normally employed to analyze experiments is also introduced, with explicit expressions derived for Fluorescence Depolarization.
The chapter discusses contact-induced phenomena, the models used in linguistics to represent processes of diffusion, and the principles that govern them. It explains several cases of diffusion across language barriers, borrowing and substrate effects, dialect contact, and new-dialect formation.
In addition to time and place, which are inseparable from sociolinguistic variation, language may vary according to age, social class, sex or (social) gender, ethnicity, medium, style, and register. Contact between speakers often leads to change, and different patterns result according to whether this contact involves first-language (L1) or second language (L2) acquisition. Thus, ‘family tree’ aspects of language change are largely accounted for by transmission (involving L1 acquisition), whilst ‘wave model’ changes can be explained in terms of diffusion (involving L2 acquisition). Languages with a high degree of L2 contact will tend to simplify, whilst stable bilingualism or isolation will often lead to complexification. Contact may be interlinguistic or intralinguistic, sometimes resulting in complex linguistic repertoires, with up to four different levels existing simultaneously (national standard, regional standard, interdialectal koiné, local dialect). Contact may also result in code-switching, the emergence of contact vernaculars, and ‘language death’. The receptiveness of a variety to contact influence depends on the extent to which its social networks are open or closed and on the social attitudes of its speakers. Standard languages emerge through a variety of conscious and unconscious processes, and attempts may be made to give non-standard speech varieties a distinct linguistic identity through codification and the creation of literature.
The chapter looks at the effect of natural barriers on linguistic configuration and diffusion through illustrations of cases from Arabic and other languages. It provides examples of how different types of topographical features either facilitate or hinder communication, thus affecting the diffusion of linguistic features. It also provides a thorough introduction to the Arabic linguistic atlases available, from 1915 into the twenty-first century. The chapter highlights cases of language isolation and language contact involving Arabic.
The Universal Declaration of Human Rights (UDHR) is thought to have shaped constitutions profoundly since its adoption in 1948. The authors identify two empirical implications that should follow from such influence. First, UDHR content should be reflected in subsequent national constitutions. Second, such reflections should bear the particular marks of the UDHR itself, not those of the postwar zeitgeist more broadly. The authors examine the historical evidence at various levels to identify and untangle the UDHR's impact. In a macro analysis, they leverage an original data set on the content of constitutions since 1789. They explore historical patterns in the creation and spread of rights, and test whether 1948 exhibits a noticeable disruption in rights provision. The authors build a multivariate model that predicts rights provision with constitution- and rights-level covariates. To gain further analytic leverage, they unearth the process that produced the UDHR and identify plausible alternative formulations evident in a set of discarded proposals. The authors further test the plausibility of UDHR influence by searching for direct references to the document in subsequent constitutional texts and constitutional proceedings. The evidence suggests that the UDHR significantly accelerated the adoption of a particular set of constitutional rights.
In this chapter we address structural (long-term) factors that may affect the fate of regimes across the world in the modern era. This includes geography (e.g., climate, soil, topography, and waterways), Islam, European influence (via colonialism, religion, language, and demography), population, and diversity (ethnic, linguistic, or religious).
This chapter develops and tests hypotheses about possible influences that lie outside national borders. There are many good reasons to expect that domestic factors are not the sole determinants. We lay out a theoretical framework that systematically catalogues most of the possible international hypotheses: exogenous shocks and endogenous networks such as those linking neighbors, allies, and colonizers and colonies. We then test selected hypotheses about exogenous shocks and contagion – the spread of democracy outcomes from country to country through various international networks. Surprisingly, contagion at first appears to be real but so small that it could be ignored when studying domestic influences. However, for some kinds of contagion our analysis implies that the long-run effects grow quite large and must be taken into account if we want to understand how democracies develop and decline. This paradox leads us to conclude that international influences are a hidden dimension of democratization.
The momentum exchange between lattice atoms and conduction electrons together with the stress gradient along the metal wire embedded into the rigid confinement are two major driving forces for electromigration-induced evolution of stress and vacancy concentration. The growth of mechanical stress causes an evolution of a variety of defects that are inevitably present in the metal, leading to void formation. It affects the electrical properties of the interconnect. In order to estimate the time to failure caused by voiding, the kinetics of stress evolution should be resolved until the first void is nucleated. Then the analysis of the void size evolution should be performed in order to trace changes in resistances of individual voided lines and vias. In this chapter, we review the major results that have been achieved with the 1D phenomenological EM model. We demonstrate its capability to predict the transient and steady-state distributions of the vacancy concentration and the hydrostatic stress, a void nucleation, and its growth, and also a drift of small voids along a metal wire. Despite its simplified nature, the 1D model is capable of addressing the confinement effect of ILD/IMD dielectric on EM-induced degradation, and also the effect of metal grain structure.
Scaling on-chip Cu wiring dimensions has degraded electromigration (EM) reliability with the same metallization and rapidly increased Cu resistivity. The size effects in EM and resistivity were caused by increased contributions from EM-induced mass flow and electron scattering with interfaces and grain boundaries, respectively. The EM Cu interconnect lifetime had further degraded by the decrease in the void volume required to cause EM failure. The Cu interconnect resistance was further increased by increasing the volume fraction of barrier/liner in metal wires that were required to produce chips with good reliability. In this chapter, we review the Cu microstructure and resistivity for various CMOS technological nodes, the basic physics of the EM phenomenon addressing EM mass transport, lifetime scaling rule, and damage formation in Cu damascene line structures. This is followed with discussions on Blech short length and EM scaling rule. Several techniques developed for improving EM reliability using upper-level dummy vias, impurities, Cu surface treatments, alternated liners, and surface metal coating are discussed together with the effects of Cu microstructure, atomic layer deposition MnOx liner, and Cu/carbon nanotube composite line on EM. Finally, the EM lifetimes, failure mechanisms and activation energies through various technological nodes are presented.
Learn to assess electromigration reliability and design more resilient chips in this comprehensive and practical resource. Beginning with fundamental physics and building to advanced methodologies, this book enables the reader to develop highly reliable on-chip wiring stacks and power grids. Through a detailed review on the role of microstructure, interfaces and processing on electromigration reliability, as well as characterisation, testing and analysis, the book follows the development of on-chip interconnects from microscale to nanoscale. Practical modeling methodologies for statistical analysis, from simple 1D approximation to complex 3D description, can be used for step-by-step development of reliable on-chip wiring stacks and industrial-grade power/ground grids. This is an ideal resource for materials scientists and reliability and chip design engineers.
This paper presents the comparison of the microstructure of the interface zone formed between titanium (Ti Gr. 1) and steel (P265GH+N) in various processing stages—directly after explosive welding versus the annealing state. Transmission electron microscopy technique served as an excellent tool for studies of the sharp interface in-between the waves. Directly after the welding process in this area, a thin layer of the metastable β-Ti (Fe) solid solution was observed. In the next step, two variants of annealing have been employed: ex situ and in situ in TEM, which revealed the complete information on the interface zone transformation. The results have shown that during the annealing at 600°C for 1.5 h, the diffusion of carbon towards titanium caused the formation of titanium carbides with a layered arrangement. Compared to our previous studies, the carbides found here have a hexagonal structure. Furthermore, changes in the dislocation structure were observed, indicating the occurrence of recovery processes. Possible reasons for differences observed in the microstructure of the interface formed due to ex situ and in situ annealing are also discussed. The microstructure observations are accompanied by the microhardness measurements, which showed that the annealing caused a significant reduction in the microhardness values.
This article sets out to reconsider the history of curse tablets in the ancient Mediterranean world as the history of a technology, one marked by episodes of innovation and appropriation. Attempts to write a history in terms of diffusion or of the spread of classical ideas or of magic have failed to convince, and most recent studies focus on the particularities of specific tablets or groups of tablets. This article argues that, if human and object agency are taken into account, it is possible to explain both the discontinuities in the history of curse tablets and also the shape of their thousand-year history. Curse tablets emerge as a technology the affordances of which allowed it to be put to many uses in many different social locations formed by the complex and shifting cultural contours of antiquity.
For over two millennia, China has sustained the largest single human society on the planet through the development of one of the most sophisticated agrarian systems in history. Even until quite recent, agriculture occupied a central place in the Chinese economy, commanding a dominant 60 to 70 percent of the total economy throughout. Agricultural institutions define the Chinese economic system and agricultural production drove long-run economic change or growth in China. Agriculture was at the center of the Great Divergence debate. Agricultural harvest or failures sometimes spelled the rise and fall of dynasties throughout history. Moving to the modern era, Chinese agriculture became the scapegoat for China’s modernization failure and was regarded as the incubator for Communist revolution. However, given its overriding importance, research on modern Chinese agriculture has been surprisingly understudied for the last few decades.
Historical and comparative social scientists are increasingly interested in explaining the spread of innovations—which social scientists commonly refer to as diffusion and, broadly conceived, can include the spread of new ideas, behaviors, technologies, and institutions. However, in spite of the profusion of studies, researchers do not always specify a diffusion model or its underlying causal mechanisms. Whereas many studies document spatial diffusion, not all specify a vector, model flows of influence and information, or show how people and places are connected (tied) to one another. In reviewing some of the most important work on the spread of religion, violent conflict, and social movements over the last few decades, it is clear to us that social network analysis has revolutionized the historical study of diffusion. Even so, many studies have yet to embrace concepts, methods, and measures from social network analysis. Nevertheless, we are convinced that the combination of historical perspectives on change and innovation, new methods of historical data collection and analysis, and growing sophistication in the application of network concepts and models is shedding light on a host of historical questions and contributing to our general understanding of diffusion.
Chapter 6 assesses why ‒ though facing similar stalemates and other structural challenges ‒ two adjacent districts in Zambézia province experienced the diffusion of militias so differently. The chapter shows that communities learned from neighboring communities about how militias formed and “diffusion agents” migrated to spread the message of militia success, which helped initiate militia diffusion. However, “sustained diffusion” ‒ the persistence of militia activity in a district and integration of the militia into the local security apparatus ‒ depended on the cohesion of elites. The chapter explores the validity of the argument by analyzing the diffusion of the Naparama to a district in Nampula province.
The diffusivity and diffusion mechanisms of hydrogen together with with deuterium and lithium, parallel to the c axis of quartz, were investigated experimentally at 800°C, 0.1 GPa with the activity of H2O or 2H2O ≈ 1 [2H is used throughout this work to describe deuterium rather than D, to avoid confusion with the diffusion coefficient, D]. The pH was set using mixtures of H2O (or 2H2O) and HCl. Three types of experiment were conducted: (1) H-in/Li-out; (2) 2H-in/H-out; and (3) 2H-in/H + Li out, using three different natural quartz crystals as starting materials. Profiles of H, 2H and Li were measured using Fourier-transform infrared (FTIR) spectroscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). H, 2H and Li are charge-compensated by Al3+ replacing Si4+, or by excess O2–. The total atomic concentration of monovalent cations appears to remain constant over the duration of the experiments. The resulting diffusion profiles are different for the three experimental designs and three starting materials, and some show complex shapes inconsistent with simple diffusion. A multi-site diffusion–reaction model is developed, with the theory based on previous models that have been derived mainly on the basis of conductivity measurements. In these models, the monovalent cations move away from their charge-balancing ion then diffuse rapidly to another site. The mobility of the monovalent cations is described by both a diffusion coefficient and an equilibrium constant that enables dissociation of the immobile charge-balanced defects. This model can describe complex step-shaped profiles formed in H-in/Li-out experiments, profiles with local maxima ('humped’ profiles) in 2H-in/H + Li out experiments, and error function-shaped profiles in 2H-in/H-out and previously published Li-in/H-out experiments. Our data provide support for models previously proposed for quartz. Studies of the lengths and forms of diffusion profiles from such experiments provide a useful complement to assertions from conductivity experiments.
Over the past century, Great Power transitions have led to the spread of autocracy in two distinct ways. First, the sudden rise of autocratic Great Powers led to waves of autocracy driven by conquest but also by self-interest and even admiration, as in the fascist wave of the 1930s or the post-1945 communist wave. Second, the sudden rise of democratic hegemons led to waves of democratization, but these waves inevitably overextended and collapsed, leading to failed consolidation and rollback. While these two categories - rollback from democratic overstretch, and hegemonic authoritarian cascades - both look like autocratic diffusion, they stem from very different causes. This chapter examines the relationship between Great Power transitions and regime diffusion. A key question is whether modern democratic decline is a post-1991 correction – that is, the delayed but inevitable overstretch of the post-Soviet wave – or the beginning of a distinct new wave of autocracy.
To solve the uncertainty of the platinum (Pt)–palladium (Pd) phase diagram, especially the existence of a suggested miscibility gap, atom probe tomography (APT) was used to determine the time evolution of the composition after heat treatment. Due to the extraordinarily slow diffusion in the temperature range of the controversial phase separation, the investigated volume was limited to nano-sized multiple layers deposited by ion beam sputtering (IBS). The evaporated volume was reconstructed from the obtained datasets and the respective diffusion coefficients were determined using the Fourier series solution of the diffusion equation. Beginning with pure Pt and Pd layers annealed at 673, 773, 873, and 973 K, the mixing appears to be purely diffusion controlled in the chosen annealing times, but the state of complete mixing was still not observed. Therefore, extended isothermal annealing sequences at 673 and 773 K with pre-alloyed layers have been carried out. They clearly suggest complete mixing even at the lowest investigated temperatures.