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1.
A new quasi three-dimensional, time-dependent meridional continuity equation for ionization in the ionospheric F-region, taking into account production, loss, electromagnetic and wind drifts, has been derived. This was coupled to the momentum equations for horizontal neutral winds so as to obtain a self consistent solution for the effects of neutral winds on the low-latitude distribution of ionization throughout East Asia. For simplicity, the non-linear inertia terms have been neglected in the wind calculations. The numerical scheme used for solving the coupled equations is given and the selection of input parameters to the numerical model discussed.  相似文献   

2.
This paper explores the subject of museum geographies, focusing particularly on the development of museum policies in a changing political context. The empirical focus is the emergence and transformation of the museum programme Renaissance in the Region, which is linked to the concepts of primary, secondary and tertiary spatialisations presented by Michel Foucault. The paper discusses the development of the programme and how it transformed aspects of the primary, secondary and tertiary spatialisations of museums in England, before focusing attention on the geography of school visits to museums. The results of two extensive studies of school visits to museums in the programme suggest that large numbers of visits come from schools located in areas with high indices of multiple deprivation and income deprivation affecting children. It is argued that this social geography reflects the tertiary spatialisation of museums linked to their emergence in areas of past industrial development, although practices linked to reconfigurations of the primary and secondary spatialisation as part of the Renaissance in the Regions programme may also have played some role. The paper concludes by discussing recent changes in government policy and the degree to which the ‘New Renaissance’ policy may signify reductions in the social reach of museums into areas of social deprivation and exclusion.  相似文献   

3.
This article explores the ‘more-than-work’ aspects of the lives of vulnerable women who street-sex work. Particularly, we are interested in the differences between the women’s experiences, within the broader context of power structures as manifested in neoliberal cities. Few studies have explored this aspect of street-sex workers’ lives and theorisations of the co-creation of environments tend to elide the experiences of the most vulnerable people. Specifically, we explore the relationships that these women have with two environments: the quotidian (where they undertake routine everyday activities), and the gentrified (relating to changes in the spaces in which they live and work). We find that their experiences are extremely local, and heavily contingent on the services made available to them (or not) by the statutory and third sectors, and the emotional contacts they make, particularly in third sector support services. This challenges some of the literature which suggests a separation of ‘home’ and ‘work’, and which finds close associations between women who street-sex work. While places designed by the third sector are more responsive to these women, they are also more vulnerable to closure through lack of funding. This contributes to a significant degree of ontological non-linearity and ontological insecurity in these women’s lives.  相似文献   

4.
The vertical structure of AGW (atmospheric gravity wave) associated fluctuations of ionospheric plasma parameters for the 100–240 km altitude range in the daytime of 7 September 1988 has been investigated by making use of the data provided by the Tromsø measurements in the EISCAT CP1 observation mode.The wave power profile vs height has been studied by integrating the power spectral density in each altitude. The essential feature of the power variation can be explained in terms of the energy conservation of AGWs propagating in a dissipative thermosphere. Intrinsic propagation parameters of the dominant AGW have been successfully estimated with a method based on the retrieval of the Doppler effect due to the horizontal prevailing wind. From the fluctuation structure analysis in a time-altitude frame, a downcoming AGW has been clearly identified. This downcoming wave might have been reflected from a wind shear at the altitude around 200 km, which is inferred from the meridional prevailing wind profile.  相似文献   

5.
The Temple Bar project in Dublin has been widely viewed as a model of culture‐led regeneration. However, the outcomes of the project show that many of its original aims, such as the maintenance and enhancement of a diverse range of uses to cater for both the needs of the local population and those of investors, have not been achieved. This would seem to be in part the result of the high priority given to image enhancement at the expense of social objectives.  相似文献   

6.
ABSTRACT

There is increasing interest in the role of agency in policy processes for creating effective change. In this paper I explore the critical role of policy entrepreneurs in both creating and capitalising on windows of opportunity through creative framing of issues. I combine Kingdon’s multiple streams framework of the policy, problem and politics streams with the three types of social movement framing – diagnostic, prognostic and motivational – to analyse a case study of pragmatic and innovative policymaking in Australian Indigenous policy. I find that pragmatic policy entrepreneurs used framing to actively refine available policy solutions, particularly in response to structural barriers, and played an active role in brokering the problem in ways to make it politically acceptable. This confirms the importance of ideational processes, and the critical role of framing, in creating windows of opportunity for significant reform.  相似文献   

7.
8.

A re‐examination of the lithic remains from the preboreal site of R?rmyr II by means of the method of refitting has shown that the site represents the remains from a single occupation. In this article the authors focus on various behavioural aspects recognized within three contemporaneous activity areas on the site. Furthermore, the idiosyncratic knapping characteristics of the people who produced the material will be discussed. By distinguishing between the various types of refits represented, in addition to examining the implications of the typological inventory, the site of R?rmyr II has been characterized as a short‐term hunter's camp‐site, and not as a specialized hunting station.  相似文献   

9.
The H, D and Z average daily variations for five international quiet days are compared for Huancayo (12°S, 75°W, dip +1.9°) and Eusébio near Fortaleza (4°S, 39°W, dip −3.5°) in the South American region, for the 12 successive months, October 1978-September 1979. The H range shows that the electrojet is weaker in the Fortaleza region. Also, the electrojet center has latitudinal excursions from month to month at both the locations, but not in a similar way. The D variations indicate excursions of northern hemisphereSq current systems into the southern hemisphere (or vice versa) but in a dissimilar way at Eusébio and Huancayo. Also, significant ΔD magnitudes are noticed even at midday, indicating possibility of meridional currents. It seems that the overhead Sq current pattern changes in form, while moving over from the Fortaleza region to the Huancayo region.  相似文献   

10.
During the heightened cultural activity of the Celtic Revival, the moral ownership and utilisation of Ireland's literary remains became an important cultural issue. At the same time, many nineteenth- and early twentieth-century Irish writers were concerned to ‘retell’ ancient stories in ways which explored their relevance to the modern world. One of the most retold tales from the period was the story of Déirdre and the Sons of Usnach. The story of Déirdre broaches one of the most ubiquitous of human experiences – betrayal – and it does so in relation to both political and interpersonal behaviour. This essay examines two dramatic treatments from the early years of the century: W.B. Yeats's one-act Deirdre (1907) and J.M. Synge's Deirdre of the Sorrows, unfinished at the time of his death and finally published in 1910. This essay looks to account for the particular ways in which each author inflects the legend in terms of their own concerns, and in particular how both Yeats and Synge engaged with a discourse of betrayal that – although always significant in Irish cultural history – was moving to a position of centrality in Irish national life in the years leading up to the revolutionary period.  相似文献   

11.
The spatial resonance mechanism which sets in when the plasma drift velocity matches the phase velocity of atmospheric gravity waves in the ionosphere is applied to explain large-scale structures of the equatorial spread-F. The resonance condition is examined for reasonable parameters of travelling ionospheric disturbances, plasma drift and neutral wind velocities. It is shown that the resonance condition can be fulfilled in equatorial regions during the post-sunset hours. The measured drift velocities of patches of range-type equatorial spread-F are similar to measured plasma drift velocities. Some spread-F structures observed with the RTI-technique at Jicamarca, range-type spread-F observed on ionograms of Huancayo as well as the occurrence of spread-F patches observed with transequatorial propagation experiments do occur after the vertical plasma drift reverses from upward to downward. The periods, wavelengths and velocities of the large-scale structure of the spread-F patches appear to be similar to those parameters for medium-scale TID's. It is argued that a non-linear break-up of resonance-steepened TID's gives rise to the quasi-periodic structures which are typical for the range-type equatorial spread-F.  相似文献   

12.
The Howard government reoriented the then existing institutionally based financial regulation towards a functionally based regime with new prudential and disclosure regulators in 1998. This paper uses the governmental agenda-setting framework of John Kingdon to explain this financial regulatory change undertaken in Australia following the Wallis Inquiry of 1996. It also examines the role of the Inquiry in the policy process. It shows that the financial regulatory change was on the bureaucratic agenda of the Treasury Department. A window of opportunity opened for the Treasury following the 1996 election, with the new Howard government keen to achieve financial regulatory reforms to address future regulatory challenges proactively while the new Treasurer Peter Costello wanted to consolidate his power within markets and politics. Costello coupled the Treasury's solutions to problems and to political processes. The Wallis Committee was ‘packed’ by the government in accordance with its regulatory policy preferences. Its role was to legitimise the government's policy preferences publicly, and to transfer the ‘governmental agenda’ into the ‘public agenda’. However, this was not a case of the government pressuring for its policy preferences over the financial services industry. In fact, the Inquiry was used as a venue to generate industry and public support for the regulatory changes, and was used to build a network of alliances within and outside the parliament.  相似文献   

13.
The promotion of closer settlement in the Australian state of Victoria between 1898 and 1914 was viewed as a panacea to many of the problems that beset the state. The region known as the Western District of Victoria was seen as particularly suitable for the application of land re-settlement policy. The study of this region highlights several important features of the closer settlement experiment in Victoria. First, it illustrates how the basic principles of closer settlement were used to further the interests of particular groups. Second, it highlights the flaws in foundations of the Closer Settlement Act which impacted on the settlers chances of success. And thirdly it points to the disastrous implications of policy implementation that paid little attention to the geographical and economic parameters governing the outcome of farming enterprises.  相似文献   

14.
15.
Daily variations in H at Alcântara (dip +3.8°) and Eusébio (dip − 6.5°), two stations in the equatorial electrojet region in Brazil, are compared. The electrojet in NE Brazil exhibits N-S asymmetry. The discrepancy between the daily variation range in H indicates the presence of complicated ionospheric currents in this region and warrants a detailed investigation.  相似文献   

16.
17.
This paper reports on results of numerical calculations for conditions under which the anomalously high absorption of radio waves appears and disappears at middle atmosphere heights, having characteristic time constants of about 24 h. In the calculations we have solved a system of equations which are self-consistent in a one-dimensional approximation and govern the temperature and neutral and ion composition behaviour in the height range 40–150 km. The values of the turbulent transfer coefficient and turbulent energy dissipation rate were calculated for the case of the anomalous absorption commencement, using experimental data pertaining to the vertical structure of the wind and temperature field. The results derived from numerical calculations involving evidence of turbulent processes were used to interpret some characteristic properties of neutral and charged particles, temperature and densities for day-time conditions with anomalously high absorption. The lack of experimental data on winds and temperature throughout the height range under study for the dates with normal absorption forced us to use indirect measurements in making assumptions about the vertical profile of the turbulent transfer coefficient and the values of the turbulent dissipation rate. The results thus obtained agree with measurements of electron density, temperature and hydroxyl emission intensity (the hydrogen content decreases as the conditions change from anomalous to normal). There are, however, discrepancies between calculated and measured atomic oxygen densities.  相似文献   

18.
Brenda E. F. Beck. Peasant Society in Koñku: A Study of Right and Left Subcastes in South India. Vancouver: University of British Columbia Press, 1972. xix + 354 pp. Diagrams, tables, appendixes, glossary, bibliography, and index. $16.50.  相似文献   

19.
Abstract

The purpose of this paper is to introduce large questions about the transfer of technology by way of a case study in technological diffusion. At the same time the paper illustrates some of the possibilities and limitations of a narrow case study and underscores the need for some kind of synthesis or theory to help our understanding of technology diffusion. The differential gear commonly found in the rear axle of motorcars is a critical piece of mechanical technology. Over the past 250 years it has been applied for a variety of purposes each of which exploited its essential principle of allowing the division of a driving force—a division caused by intercepting it with some kind of weight or independent force (kidney cam in the equation clock; weights on the 'crown' wheel of a windmill governor and in a dynamometer; the weight of rovings on bobbins in the roving frame; friction of the road as a car corners).  相似文献   

20.
The effect of the midday recovery of absorption (MDR) during the polar cap absorption (PCA) of 19–21 March 1990 is investigated using data from 25 riometer stations in both hemispheres. The measured variations of absorption are compared with those calculated from a model. Three main aspects are considered:
  • 1.(1) The solar and geophysical conditions under which the effect appears,
  • 2.(2) The essential morphological features of the phenomenon,
  • 3.(3) The relative contributions of (a) diurnal variations in the geomagnetic cut-off energy and (b) an anisotropic pitch-angle distribution of the solar protons to the development of the MDR.
The principal morphological features of the MDR effect are found to be as follows:
  • 1.(a) the width of the area affected by MDR is about 10° of invariant latitude,
  • 2.(b) there are two regions, respectively below and above 65° latitude, in which the MDR properties are different,
  • 3.(c) the maximum duration of the MDR effect is about 12 h,
  • 4.(d) there are distinct geomagnetic conjugucy effects in MDR.
There are solid reasons to suggest that the MDR at latitude 65–70° is due to the combined influence of a diurnal variation of geomagnetic rigidity, and the pitch-angle anisotropy of the solar protons. The MDR at lower latitudes (Λ = 60–65°) seems to be produced primarily by diurnal variations of the cut-off rigidity.  相似文献   

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