A numerical model of the ionospheric dynamo—I. Formulation and numerical technique

A new method of numerically solving a suitably formulated ionospheric wind dynamo equation for electrostatic potential and field is developed. Unlike in many other dynamo models, the upper boundary does not exist and the formulation asymptotically approaches the equatorial boundary condition. Therefore, it naturally incorporates the symmetric, asymmetric E- and F-region dynamo actions in any given ionosphere and any given global or local wind field. It also enables the equation to be posed as an initial value problem and solved numerically using an efficient, accurate, stable and fast integration method of ordinary differential equations. The numerical technique can be extended to compute three dimensional dynamo-generated electric currents in the ionosphere.     

Seismic Hazard Analysis Using Discrete Faults in Northwestern Pakistan: Part II – Results of Seismic Hazard Analysis

This article is the second of two companion articles that evaluate seismic hazard in northwestern (NW) Pakistan. Using the properties and characteristics of discrete faults in NW Pakistan described in the first article, probabilistic and deterministic seismic hazard analyses for 11 major cities in NW Pakistan were conducted. The results from both probabilistic and deterministic seismic hazard analyses exhibit good agreement. Median deterministic spectra compare favorably with uniform hazard spectra (UHS) for 475- or 975-year return periods, while the 84^th-percentile deterministic spectra compare favorably with the UHS for a 2475-year return period. Peak ground accelerations (PGAs) for 2475-year return periods exceed 1.0 g for the cities of Kaghan and Muzaffarabad, which are surrounded by major faults. The PGAs for a 475-year return period for these cities are approximately 0.6g — 3 to 4 times greater than estimates by previous studies using diffuse areal source zones. The PGAs for some cities located farther from faults (including Astor, Malakand, Mangla, Peshawar, and Talagang) are similar to those predicted using diffuse areal source zones. Seismic hazard maps for PGA and spectral accelerations at periods of 0.2 s and 1.0 s corresponding to three return period (2475, 975, and 475 years) were produced. Based on deaggregation results, a discussion of the conditional mean spectra for engineering applications is presented.     

The two opposing impacts of heritage making on local communities: residents’ perceptions: a Portuguese case

This article examines the impact associated with the making of heritage and tourism at a destination. Special attention is paid to the residents’ perceptions of the impact. The examination is focused on the rural village of Sortelha, in Portugal, where, in recent decades, a state-led programme was implemented in order to renovate the historic buildings and built fabric and to generate benefits for the local community. Based on ethnographic materials collected in 2003, 2009 and 2013, the study demonstrates that the making of heritage may give rise to two opposing impacts simultaneously – increased social cohesion and place pride, on the one hand, and envy and competition (and, hence, social atomisation), on the other hand – and that residents are entirely cognisant of the tension between the two. The study has the potential to contribute to both the theoretical and the applied literature on heritage making.     

Seismic Performance Assessment of Steel Frames with Shape Memory Alloy Connections. Part I — Analysis and Seismic Demands

This article is the first of two companion articles that evaluate the seismic performance of steel moment-resisting frames with innovative beam-to-column connections that incorporate shape memory alloys (SMAs) to dissipate energy and provide recentering effectively during large earthquakes. Two types of SMA elements are considered: (1) superelastic SMA elements with recentering capability and (2) martensitic SMA elements with high energy dissipation capacity. This article describes the fundamental engineering characteristics of these SMA connections, their modeling in connections for nonlinear dynamic finite element analysis of building frames, and the validation of these connection models using data from full-scale experimental tests that were performed in previous research at Georgia Institute of Technology. Using three- and nine-story partially restrained (PR) moment frames selected as case studies from the SAC Phase II Project, nonlinear time history analyses of frames with and without SMA connections were conducted using suites of ground acceleration records. The beneficial effects of SMA connections on peak and residual deformation demands are quantified and discussed.     

Gravity waves from O2 nightglow during the AIDA '89 campaign II: numerical modeling of the emission rate/temperature ratio, η

The dependence of η, the ratio of emission rate fluctuation to temperature fluctuation, on the gravity wave parameters and chemical parameters is developed using a model for the O₂ airglow's response to a gravity wave. The model is in the Eulerian frame of reference using the traditional linearization and perturbation method. Two photochemical mechanisms, the three-body recombination mechanism and the two-step transfer mechanism and two kinds of waves, evanescent and internal, are separately discussed in detail. Results of the model are compared with other existing models of η(O₂) and found to be in agreement. The predictions of this model agree fairly well with the available gravity wave measurements in the magnitude of η, but the predicted phases are somewhat larger than those normally observed.     

A numerical study of the lunar tide in the mid-latitude F2-region of the ionosphere—II. Oscillations of the ion and neutral gas velocities

The drift due to the lunar electric field which is communicated from the ionospheric E-region causes a re-distribution of the electron density and a neutral air motion in the F2-region. The lunar tide in the electron density of the F2-region due to the lunar electric field has been obtained and discussed in Part I. The lunar tides in the ion and neutral velocities which are obtained in the same way are dealt with in this paper. It is found that the lunar tidal oscillations in the drifts and neutral winds markedly depend on the solar time, and that the amplitude and phase in the x-component of the drift averaged over the solar times are 10.1 m s⁻¹ and 2.6 h and those in the x-component of the neutral wind are 4.6 m s⁻¹ and 4.3 h, respectively, at 45.0° dip.     

A numerical model of the ionospheric dynamo—III electric current at equatorial and low latitudes

Using the general dynamo model and its special cases derived in a previous paper, the distributions of three dimensional electric current density in a magnetic meridional plane in the equatorial and low latitude ionosphere are computed. The winds generating the ionospheric dynamo are tide-like and locally periodic, similar to those in an internal gravity wave. Very large (several μA m⁻²) field-aligned current density is obtained in the equatorial region at places of sharp vertical gradients of the wind velocity. The currents generated by locally periodic winds of latitudinal wavelength less than several hundred kilometers do not significantly affect the normal equatorial electrojet.     

In search of working‐class memory: Some questions and a tentative assessment

This article analyzes the circumstances under which the concept of mémoire ouvrière has emerged in France and its relation to a change in the conception of history as well as the status of the historian. It presents the debate that centered on the meaning and function of the research into workers’ memory and the specificity of its object. Its approach is comparative: though focusing on research done in France it refers to Great Britain, Italy and the U.S. Differences in workers’ memories according to trades, traditions and national experiences are analyzed. And so is the relationship between workers’ memory and labor organizations: it is seen to be deeply political but not one‐sided as is often claimed. La Mémoire ouvrière cannot be dissociated from workers’ consciousness, class identity and from the purposefulness of memory. Finally, the article stresses the ambiguities and contradictions faced by the attempt to recapture workers’ memory in an academic research context.     

The politics of Australia's international economic relations: Adjustment and two‐level games

Economic adjustment, a political priority for Labor governments throughout the second half of the 1980s, and in contrast to earlier Australian scholarship and practice, is now recognised to be an internationally, as well as a domestically, determined and constrained enterprise. Theoretical developments in international political economy in North America of late have provided a variety of approaches for conceptualising this twofold enterprise. Taking two cases (the development of the Cairns Group and its activities in the Uruguay Round of Trade Negotiations and the development of Asia Pacific Economic Cooperation) this paper looks at two of these approaches—to show how they can contribute to the understanding of international economic policy under Labor in the late 1980s and early 1990s.     

Buried soils in the context of geoarchaeological research—two examples from Germany and Ethiopia

Pedology is a discipline with a wide range of applications in geology, geomorphology, archaeology, geoarchaeology and geography. Especially paleopedology aims are to answer questions about climatic changes, rates of pedogenic processes, pedostratigraphy, suitability of former surface soils and human occupation. In combination to other disciplines, pedology aims to advance geoscientific methods at different scales, and during the last decades, (paleo)pedological research increasingly touched archaeological fields whereby soil research was mostly somehow included in geoarchaeology. When the term ‘archaeopedology’ was introduced in the 1940s, researchers were already aware of the importance of the subject ‘soil’ as being a key figure when answering questions of site formation history, cultural chronology and environmental change. The present paper aims to reintroduce this term to the scientific community and to accentuate the importance of buried soils within geoarchaeological research. Shown by two different studies, one from Upper Palaeolithic sites in the Ueckermünder Heide/Germany and one from ancient Yeha/Ethiopia the archaeopedological approach highlights the importance of pedological research on- and off-site excavations by clearly bridging a gap between archaeology, geoarchaeology and (paleo)pedology.     

Dynamics of the Antarctic and Arctic mesosphere and lower thermosphere regions—II. The semidiurnal tide

The semidiurnal tidal dynamics of the Antarctic and Arctic mesopause regions (95 ± 15 km) are investigated through comparative analyses of monthly mean tidal wind fields determined from radar measurements at the Scott Base (78°S), Molodezhnaya (68°S), and Mawson (67°S) stations in the Antarctic, and the near-conjugate stations of Heiss I. (81°N) and Poker Flat (65°) in the Arctic region. The main feature common to all stations is the fall equinoctial maximum in amplitude (10–20 m s⁻¹), which is also reproduced by the most recent numerical tidal model. However, the wintertime amplitude growth with height and the shorter vertical wavelengths characterizing the model are features not reflected in the data. There is also a spring equinoctial maximum in the Antarctic data which the model does not reproduce.Examination of interannual variability reveals characteristics similar to those noted in Part I for the mean zonal wind; namely, some degree of year-to-year variability superimposed on apparent long-term decreases of order 0.3–0.5 m s⁻¹ yr⁻¹ (depending on month) in the Southern Hemisphere semidiurnal tidal amplitudes. Numerical simulations presented herein indicate that changes of this magnitude cannot even be induced (via mode coupling) by a change in the mean zonal wind field of order 30%, and are more plausibly explained by a secular change in the tidal forcing by ozone insolation absorption. However, contrary to Part I, the annual mean tidal amplitude is not characterized by any significant secular trend, remaining within the 10.0 ± 2.5 m s⁻¹ range throughout the 1970–1986 period. Analyses of other data sets are required to ascertain confidence in the apparent trend reported here.     

The three last years of Manuel II Palaeologus' reign between two stroke attacks: aphasia or not?

The authors attempt to solve the enigma about the possible aphasia of the Byzantine Emperor Manuel II Palaeologus (1391-1425) in the 3-year period between his first and his second and fatal stroke. The texts of historians and chroniclers reveal that Manuel remained semi-paralyzed at bed and his motor disability alienated him from the state affairs and condemned him to isolation from all embassies and contact with others, except his family. Only the funeral oration of the Bishop Bessarion raises the suspicion of a speechless emperor. All testimonies referring to this infirmity are examined.     

Buddhist buildings in England: the construction of ‘under-represented’ faith heritage in a multicultural and post-Christian setting

Until recently the ‘heritage industry’ in England overlooked buildings of minority faith traditions. Little has been written about this ‘under-represented’ heritage. Drawing on data from the first national survey of Buddhist buildings in England, we examine the ways in which Buddhist heritage is beginning to be incorporated into the state-funded ‘heritage industry’ as well as how Buddhist communities in England construct heritage through these buildings. First, we draw upon spatial theory in the study of religion to examine three dimensions of minority faith buildings in England and what this tells us about the communities involved: ‘location’ (i.e. the geographical location of the buildings); ‘space’ (i.e. what the buildings are used for and their relationship to local, national and transnational scales); and ‘place’ (i.e. what types of buildings are selected by different communities and why). We then turn to theories of memory that have become popular within the study of religion as well as heritage studies. Religion understood as ‘a chain of memory’ plays an important role in heritage construction via faith buildings, and an analysis of faith buildings, their spatial dimensions and role in ‘memorywork’, helps us think through the dynamics of modern religious belief in a multicultural and post-Christian setting.     

Of reaflac and rapina: accusations of violence in two Old English lawsuits and the Libellus Æthelwoldi

This article examines the meaning and function of the Old English noun reaflac in two tenth-century lawsuit documents, Sawyer 877 and Sawyer 1211. It suggests that reaflac was the vernacular counterpart to the Latin terms violentia and rapina. Such connected terminology suggests that a collection of now lost tenth-century Old English charters, like S 877 and S 1211 in form, was the original source for the twelfth-century Ely house chronicle, the Libellus Æthelwoldi. Charter draftsmen purposefully selected a language of violence in order to delegitimize a rival party’s claim to an estate, regardless of whether any acts of violence had taken place. Reaflac formed part of this narrative strategy in early English lawsuit documents because of its association with contemporary discourses on moralized wrongdoing.