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1.
Lei Xu 《GeoJournal》2011,76(5):501-524
Based on the tabulations of the Longitudinal Immigration Data Base, I characterized, explained and compared the 1991–1996
and 1996–2001 inter-metropolitan migration of the newly landed immigrants in Canada. The spatial and temporal patterns were
consistent with the neoclassical economic theory and the ethnic enclave theory. In making their decisions on departure and
destination choices, the immigrants were responsive to income and employment incentives, as well as the retaining and attracting
powers of ethnic communities among Census Metropolitan Areas (CMAs). The research also discovered an interesting temporal
pattern—while the inter-CMA migration of immigrants accentuated the over representation of the immigrants in Toronto and Vancouver
in the 1991–1996 period, the rise of the “secondary” CMAs led to a spatial dispersal of the immigrants in the 1996–2001 period.
This finding supplements the existing literature on internal migration of Canadian immigrants, which discovered little evidence
of an increased dispersion of immigrants over time. 相似文献
2.
3.
Diane Perrons 《GeoJournal》2002,56(4):271-280
The concept 'new economy' is widely used to characterise the outcomes of contemporary restructuring processes – but in contrasting
ways: by globalisation and the increasing use of communication and information technologies as well as by deregulation, polarisation,
feminisation of employment and new, more flexible patterns and hours of work. These tendencies are interlinked and partly
account for growing social and gender divisions. They pose problems for social sustainability but also develop differently
in different economic and social formations. This paper develops a theoretical understanding of widening social divisions
and their gendered form, indicates how these tendencies have developed to different degrees within the European Union and
illustrates how the divisions are experienced by people in a local labour market in the neo liberal UK, where social and gender
divisions are particularly wide.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
N. A. Gnatus’ M. D. Khutorskoy V. K. Khmelevskoi 《Moscow University Geology Bulletin》2011,66(3):151-157
The geological-geophysical, methological, and economic aspects of extraction and utilization of petrothermal resources (“hot
dry rock thermal”) for thermal and electric energy production were considered. Heat collectors are hydraulic fracturing zones
of natural or artificially made cracks in the crystalline rocks of the basement; these rocks have higher temperature and can
be a kind of “thermal cauldron.” Detection of such “collectors” can be carried out by geophysical methods. When pumped out
of wells and warmed to 100–300°C, waters function as a heat transfer for thermal energy supply and electric energy generation.
If the technical problem of the rapid drilling of 6–10 km wells could be solved, then petrothermal energy will become competitive
with the traditional types of energy production and supply. 相似文献
5.
The sediment-hosted disseminated gold deposits in the Oinling region are of sedimentation-slight-metamorphic origin superimposed by hydrothermal reworking at moderate-low temperatures and are well comparable with the typical Carlin gold deposits in the United States.In view of the confusing concept concerning the “sediment-hosted”and “Carlin-type” gold deposits,the authors propose that the term“sediment-hosted gold deposit”should be used in a broad sense which encompasses at least the four subtypes,i.e.,the Carlin type,the metamorphic fine clastic type,the hydrothermal sedimentary type and the vein type.In oter words,the “Carlin-type”should not be used as a synonym for “sediment-hosted”but is recommended as a subtype under the general category of “sediment-hosted gold deposits” 相似文献
6.
Matthew G. Hannah 《GeoJournal》2010,75(4):397-406
Ewald’s recent genealogy of constructions of risk in Western societies argues that the 1980s saw an important paradigm shift
to the “precautionary principle”. Critical scholars have taken up this idea as a lens through which to interpret the Bush
administration’s ‘war on terror’. I argue that 11 September 2001 actually brought about qualitative changes to this paradigm.
Bush’s pre-emptive doctrine is driven, and perhaps even more importantly, continually justified to the US population, by what
might be called the “trans-precautionary principle”, a move from “decisionism” to “actionism”, and a new radicalization of
the way fear is produced and managed. Donald Rumsfeld’s famous typology of different articulations of knowledge and ignorance
offers an excellent analytical window onto the connections between ignorance, fear and geopolitical action in this new regime.
In the latter part of the essay, his four modes of knowledge/ignorance are arrayed, for heuristic purposes, in an abstract
spatial grid organized along dimensions of the specificity and possession of knowledge. This allows a ‘mapping’ of some of
the Bush administration’s more controversial strategies in the ‘war on terror’, as a set of different pathways through Rumsfeld
Space. 相似文献
7.
Coastal flooding occurs due to storm surges generated by tropical and extra-tropical cyclones on the globe. The meteorological
forcing fields for the generation of storm surges are the tangential surface wind stress on the ocean surface and the normal
atmospheric pressure gradients associated with the weather systems. The large scale forcing from the cyclones is referred
to as the synoptic scale and storm surge prediction from synoptic scale forcing is well developed and is reasonably satisfactory
around the world. However, coastal flooding also occurs from weather systems, with forcing on a meso-scale and also from remote
forcing. It is proposed here that the term “Storm surge” be used to only refer to coastal flooding from synoptic scale forcing
and the terminology “Rissaga” be used for coastal flooding from meso-scale forcing. For flooding due to remote forcing, a
new term “Kallakkadal” is proposed. 相似文献
8.
Urmilla Bob 《GeoJournal》2004,61(3):291-300
This article contributes to a greater understanding of the linkages between women's roles, responsibilities and their use
of technology in poor rural communities. The ways in which poor rural women conceptualize technology is examined. Furthermore,
how they use their knowledge and skills to develop, modify and adapt the techniques and technical processes in which they
are involved are also explored. Additionally, the links between indigenous and modern technologies in relation to gender considerations
in poor rural contexts are examined. This article draws from findings of primary research undertaken in two marginalized rural
communities in Kwazulu-Natal, South Africa. The study reveals that the use of technologies are highly gendered and differentiated
among women. Poor rural women utilize a range of technologies in both productive and reproductive activities which are central
to their livelihood strategies, especially at the household level. Furthermore, although women are adapting and innovating
technologies their expertise remains largely unrecognized. A range of problems and constraints exist which limit women's access
to and use of technologies. A key tension identified in the study is that between the use of locally-based, indigenous technologies
and modern, external technologies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
I. A. Baksheev A. F. Chitalin V. O. Yapaskurt M. F. Vigasina I. A. Bryzgalov V. I. Ustinov 《Moscow University Geology Bulletin》2010,65(1):27-38
Three generations of tourmaline have been identified in propylite in the Vetka porphyry copper-molybdenum deposit of the Chukchi
Peninsula of Russia. Tourmaline-I is characterized by its Fetot/(Fetot + Mg) value, which ranges from 0.33 to 0.49. Tourmaline-II, which crystallizes at a lower temperature, overgrowing tourmaline-I
or occurring as isolated crystals, is distinguished by a higher Fetot/(Fetot + Mg), which varies from 0.46 to 0.72. The Fetot/(Fetot + Mg) ratio in tourmaline-III, which overgrows tourmaline-II is lower (0.35–0.49), and is identical to that of the first
tourmaline generation. This is probably caused by the beginning of sulfide deposition. Tourmalines in the deposit characterized
by complex isomorphic substitutions can be attributed to the intermediate members of the dravite—“hydroxy-uvite”-“oxy-uvite”
and schorl-“hydroxy-feruvite”-“oxy-feruvite” series. Tourmaline starts to crystallize at temperatures above 340°C. The fluid
responsible for the tourmaline deposition was magmatic, with a significant admixture of meteoric water (δ18OH
2O = −0.85 to −0.75‰). The high Fe3+/Fetot ratio (0.50) indicates high oxygen activity when the tourmaline precipitated. It has been established that the isomorphic
substitution Fetot → Al is typomorphic of tourmalines from porphyry copper deposits worldwide. 相似文献
10.
From brain drain to brain gain: reverse migration to Bangalore and Hyderabad, India’s globalizing high tech cities 总被引:1,自引:0,他引:1
Elizabeth Chacko 《GeoJournal》2007,68(2-3):131-140
This paper assesses the mutual impact of returning Indian-origin skilled workers on the cities of Bangalore (Bengaluru) and
Hyderabad, which have emerged as India’s leading “tech cities”. During the 1970s and 1980s, there was concern that India was
losing its educated workforce to the West, particularly to the United States through a phenomenon known as “brain drain”.
More recently, there is evidence that reverse brain drain is occurring, as U.S.-trained Indian professionals are returning
to their home country in increasing numbers to take advantage of new growth and employment opportunities. The effects of this
skilled, transnationally active labor force on various sectors of the economy, on the social and physical infrastructure of
Bangalore and Hyderabad and in forging and solidifying transnational linkages between India and the United States are explored
in this paper. This study also investigates the reasons why successful US professionals of Asian-Indian origin are returning
to their home country via a series of personal interviews. The paper offers Bangalore and Hyderabad as “worldwide leading
cities” with a niche status in the global Information Technology (IT) sector. 相似文献
11.
The Last Picture Show does not fall within the genre of the Western, yet the cinematic narrative mourns the loss of the iconic Westerner — a man
— and the passing of his home places that constitute the Old West. This paper is concerned with the ways in which this man
and his places are transformed along with the embryonic but inexorable emergence of the New West — and its attendant demand
for recognition of hitherto unheard voices (e.g., women, Latinos) — that accompanied significant social, cultural and political
shifts that were beginning to emerge within the country as a whole in the represented early 1950s. His represented sites of
contestation are found within the frame of the small west Texas town of Anarene, created by Larry McMurtry's novel of the
same name as the film, both of which reflect contexts of the era in which they were constructed — the mid 1960s to early 1970s.
We suggest that the film shows a great sensitivity to the ways in which particular masculinities are constituted in specific
places, to the tensions that arise from the changing nature and definitions of masculinity as they are linked to these places,
and with his sense of nostalgia and loss that accompanies his inevitable decline. But there is no clear and empowered place
for women in these new places, only a recontextualized form of a patriarchal order which is not relational and which still
maintains essentialist assumptions of gender. The Old West has taken new shape, much to the chagrin of man, but it is hardly
a New West, with its emerging and representative voices.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
The lack of adequate water supply and sanitation services is a major issue related to sustainable development in many parts
of the developing world. New strategic planning approaches which directly address users’ needs and demand—often referred to
as demand-responsive, community-based or household-centred approaches—are regarded as a crucial step towards improving the
situation. This paper investigates household needs and demand for improved water supply and sanitation services in peri-urban,
low-income settlements, known as “ger areas”, in the city of Darkhan, Mongolia. The paper is based largely on a household
survey conducted in a selected ger area subdistrict in Darkhan. The results reveal a complex picture. Even if the existing
situation can be regarded as largely “improved” in terms of the definitions stipulated by the Joint Monitoring Programme for
water supply and sanitation, it is shown that there is a need for action nonetheless. The paper also argues that the household
survey is a useful method for assessing users’ needs and demand and for meeting the requirements of demand-responsive sanitation
planning approaches. 相似文献
13.
Kirsten Valentine Cadieux 《GeoJournal》2011,76(4):341-363
This paper explores different ways that the category of nature is used in addressing landscape changes associated with exurbia
and exurbanization. Nature is an important category in the practices and representations that residents and planners use to
construct and maintain exurban landscapes. However, common ways of mobilizing nature in exurban planning discourses often
obstruct better discussion, rather than facilitate it. Invoking nature can make planning processes more difficult by providing a means
for naturalizing planning decisions and also by exacerbating struggles over whose nature will be managed in what ways. More
explicitly framing what is meant by nature in exurban planning may improve discussion of landscape problems associated with
sprawl. The goal of this paper is to contribute to creating a framework for more actively contextualizing how “nature” is
used in discourses relating to exurbanization. I suggest that such a framework would need to consider—and make explicit—themes
such as the four that I discuss in this paper: (1) the centrality of the production of nature to exurban landscapes; (2) multiple
meanings of nature that are often confused; (3) ways that normative statements about nature tend to be unquestioned in exurban
planning; and (4) the simultaneous difficulty and usefulness of critiquing and “denaturalizing” both material and discursive
nature. Explicit conversations about the role and representation of nature within residents’ and managers’ land-use practices
and ideologies could create opportunities for dialogue between residents, planners, and academics about the valuation of and
preferences for constructing particular landscapes, especially in addressing problematic aspects of the phenomena of “amenity
migration” and “sprawl.” 相似文献
14.
Kalliopi Sapountzaki 《Natural Hazards》2012,60(3):1267-1285
The article decodes and analyzes the standard functions of social and social-ecological systems when they manage their own
vulnerability. The author acknowledges these as “Resilience functions” or “Operational Resilience”. For this purpose, she
follows a “Vulnerability Actor” (V Actor)-based approach. V Actor is considered as a system faced with multiple hazards, carrying
various vulnerability facets (physical, economic, institutional, etc.) and attempting to transform, transfer, rearrange them
in time and space so as to achieve Actor’s own persistence. It is these processes of vulnerability re-arrangement that are
identified by the author as Resilience functions and which change the vulnerability not only of the V Actor performing resilience
but also others’. Performance of Resilience functions presupposes attraction and employment of resources by the Actor, not
only own, current and inherent but also other resources to be found in spatial and temporal scales external to or beyond the
Actor but which the Actor can appeal to. This attraction most probably leads to deprivation of others of the necessary resources
for their persistence, recovery, etc. When somebody’ vulnerability is reduced sometimes somewhere, it is most probable that
others elsewhere are encumbered with extra vulnerability, currently or in the future. Hence, what resilience can only do is
vulnerability re-arrangement, re-setting and management. The proposed systemic approach is documented on current state of
art regarding interactions between vulnerability and resilience to hazards and on empirical evidence from the international
experience of responses to natural hazards. 相似文献
15.
Spatial pattern analysis of marine terrace elevations from 40–30 thous. years BP was used to reconstruct sea level/geoid surface
and geoid parameters during that time. The polar flattening of geodetic ellipsoid was lower than its present value (1/298.81
and 1/298.26) respectively because of glacial-induced mass redistribution. Increase in polar stress occurred during the last
30 thous. years was possibly driven by pertubation brought to the gravitational field by disintegration of polar ice sheets
in the Northern hemisphere. But the polar flattening value becomes only half-restored during the last deglacial hemicycle.
So repetitive glacial advances during Pleistocene acted as a global “pump” for uncondensed zones at the upper/lower mantle
boundary. Dissipation of tidal energy is an order of magnitude less intensive in its Earth's rotation effect.
A contribution to the International Geological Correlation Programme Project JGCP — 274 “Coastal Evolution in the Quaternary”. 相似文献
16.
Based on analysis of the well drilling core from Subei basin, the authors conclude that during the Late Cretaceous and Paleocene,
Subei basin was linked with the sea and the deposit was affected by transgression. The cause of marine transgression may be
that since Late Cretaceous and Paleocene tension power had predominated ground-stress conditions of the East China Sea and
developed a series of half-graben-like basins filled by a huge thick sediment of the Early Tertiary in the shelf of Huabei-Bohai
gulf, Subei-South Yellow Sea and East China Sea. Consequently, seawater transgressed from the East China Sea to the Yellow
Sea and linked halfgraben-like basins on the shelf to the sea within a short period. During the sedimentation of the Late
Cretaceous Taizhou Formation and Paleocene Funing Formation, the Subei basin had formed the ostracoda-enriched dark shale,
including predominantly the whole basin E1
f
2 Formation and E1
f
4 Formation and local K2
t
2 Formation, which became the main source rocks of the basin. The evidence of paleontology, minerals in rocks and geochemistry
can help confirm the environment of the lake basin that developed during the Late Cretaceous and Paleocene. We generally designate
this environment as “near sea lake basin” and the sea-transgressed layer and member as “transgression lake basin”.Whereas,
it is generally called “inland lake and river alluvium plain” during the sedimentation of the Eocene Dainan Formation and
Sanduo Formation. This research is not only significant to the paleogeographic reconstruction of the Subei basin during the
Late Cretaceous and Paleocene, but also important in understanding the development and distribution of the source rocks and
evaluating the potential of oil and gas generation.
__________
Translated from Acta Sedimentologica Sinica, 2007, 25(3): 380–385 [译自: 沉积学报] 相似文献
17.
Today, in the early 21st century, goods, information, services, financial capital and human beings are flowing across national
borders at an ever-accelerating rate. In this context, transnationalism has become a key paradigm in the study of international
migration and urbanism. This theme issue on “Immigrants and transnational experiences in world cities” explores these new
trends in contemporary international migration, with respect to transnational communities and geographies, in articles grouped
according to four themes: international migration and world cities; highly-skilled and low-skilled immigrants; economic impacts;
and immigrant experiences in world cities. 相似文献
18.
The present study explored the effect of assimilation of Advanced TIROS Vertical Sounder (ATOVS) temperature and humidity
profiles and Spectral sensor microwave imager (SSM/I) total precipitable water (TPW) on the simulation of a monsoon depression
which formed over the Arabian Sea during September 2005 using the Weather Research and Forecast model. The three-dimensional
variational (3DVAR) data assimilation technique has been employed for the purpose of assimilation of satellite observations.
Statistical scores like “equitable threat score,” “bias score,” “forecast impact,” and “improvement parameter” have been used
to examine the impact of the above-mentioned satellite observations on the numerical simulation of a monsoon depression. The
diagnostics of this study include verification of the vertical structure of depression, in terms of temperature anomaly profiles
and relative vorticity profiles with observations/analysis. Additional diagnostics of the study include the analysis of the
heat budget and moisture budget. Such budget studies have been performed to provide information on the role of cumulus convection
associated with the depression. The results of this study show direct and good evidence of the impact of the assimilation
of the satellite observations using 3DVAR on the dynamical and thermodynamical features of a monsoon depression along with
the effect of inclusion of satellite observation on the spatial pattern of the simulated precipitation associated with the
depression. The “forecast impact” parameter calculated for the wind speed provides good evidence of the positive impact of
the assimilation of ATOVS temperature and humidity profiles and SSM/I TPW on the model simulation, with the assimilation of
the ATOVS profiles showing better impact in terms of a more positive value of the “forecast impact” parameter. The results
of the study also indicate the improvement of the forecast skill in terms of “equitable threat score” and “bias score” due
to the assimilation of satellite observation. 相似文献
19.
The evolution of terrestrial planets (the Earth, Venus, Mars, Mercury, and Moon) was proved to have proceeded according to
similar scenarios. The primordial crusts of the Earth, Moon, and, perhaps, other terrestrial planets started to develop during
the solidification of their global magmatic “oceans”, a process that propagated from below upward due to the difference in
the adiabatic gradient and the melting point gradient. Consequently, the lowest melting components were “forced” toward the
surfaces of the planets in the process of crystallization differentiation. These primordial crusts are preserved within ancient
continents and have largely predetermined their inner structure and composition. Early tectono-magmatic activity at terrestrial
planets was related to the ascent of mantle plumes of the first generation, which consisted of mantle material depleted during
the development of the primordial crusts. Intermediate evolutionary stages of the Earth, Moon, and other terrestrial planets
were marked by an irreversible change related to the origin of the liquid essentially iron cores of these planets. This process
induced the ascent of mantle superplumes of the second generation (thermochemical), whose material was enriched in Fe, Ti,
incompatible elements, and fluid components. The heads of these superplumes spread laterally at shallower depths and triggered
significant transformations of the upper shells of the planets and the gradual replacement of their primordial crusts of continental
type by secondary basaltic crusts. The change in the character of the tectono-magmatic activity was associated with modifications
in the environment at the surface of the Earth, Mars, and Venus. The origin of thermochemical mantle plumes testifies that
the tectono-magmatic process involved then material of principally different type, which had been previously “conserved” at
deep portions of the planets. This was possible only if (1) the planetary bodies initially had a heterogeneous inner structure
(with an iron core and silicate mantle made up of chondritic material); and (2) the planetary bodies were heated from their
peripheral toward central portions due to the passage of a “thermal wave”, with the simultaneous cooling of the outer shells.
The examples of the Earth and Moon demonstrate that the passage of such a “wave” through the silicate mantles of the planets
was associated with the generation of mantle plumes of the first generation. When the “wave” reached the cores, whose composition
was close to the low-temperature Fe + FeS eutectic, these cores started to melt and gave rise to superplumes of the second
generation. The “waves” are thought to have been induced by the acceleration of the rotation of these newly formed planets
due to the decrease of their radii because of the compaction of their material. When this process was completed, the rotation
of the planets stabilized, and the planets entered their second evolutionary stage. It is demonstrated that terrestrial planets
are spontaneously evolving systems, whose evolution was accompanied by the irreversible changes in their tectono-magmatic
processes. The evolution of most of these planets (except the Earth) is now completed, so that they “dead” planetary bodies. 相似文献
20.
Fezer Fritz Prof. Dr. Reichenbach Bernhard Witschel Christian MA Hell Günter Prof. Dr.-Ing. Duster Manfred Dipl.-Ing Heidrich Brigitte 《GeoJournal》1987,14(4):467-478
Airphotos have been used for topographic survey since the Twenties. The “European Space Agency” (ESA), the “Deutsche Forschungs-
und Versuchsanstalt für Luft- und Raumfahrt” (DFVLR) and “Carl Zeiss” have modified this successful technique for spacecraft
and recently have tested the system over four continents. Each of these satellite photos covers a region of 189×189 km to
the scale of 1∶800000 and may be enlarged to 1∶250000 or 1∶100000. Between the altitudes of 200 and 300 km, mapmaking or-revision
seems to be economic in zones or in countries, where existing maps are of minor quality or outdated. In this paper, examples
from deserts and semideserts in the Sudan are presented. 相似文献