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1.
Crack Coalescence in Molded Gypsum and Carrara Marble: Part 2—Microscopic Observations and Interpretation 总被引：9，自引：3，他引：6
Experimental uniaxial compression loading tests were conducted on molded gypsum and Carrara marble prismatic specimens to
study the cracking and coalescence processes between pre-existing artificial flaws. The study showed that material had an
influence on the cracking and coalescence processes (see the companion paper in this issue). As reported in the companion
paper, one of the pronounced features as observed in the high-speed video recordings was the development of macroscopic white
patches prior to the development of observable cracks in marble, but not in gypsum. This paper (part 2) deals with the microscopic aspects of the study. Specifically, the scanning electron microscope (SEM) and the environmental scanning electron microscope
(ESEM) imaging techniques were used to study the microscopic development of white patches and their evolution into macroscopic
tensile cracks and shear cracks in marble, and the microscopic initiation of hair-line tensile cracks and their evolution
into macroscopic tensile cracks in gypsum. The microscopic imaging study in marble showed that the white patches were associated
with extensive microcracking zones (process zones), while the extent of process zone development in gypsum was limited. The
comparison of the macroscopic and microscopic results indicates that the different extent of microcracking zone development,
related to the material textural properties, is a key factor leading to different macroscopic cracking behavior in gypsum
and marble.
相似文献
| H. H. EinsteinEmail: |
2.
Spatial and temporal knowledge representation 总被引：1，自引：1，他引：0
Antony Galton 《Earth Science Informatics》2009,2(3):169-187
Knowledge Representation (KR) originated as a discipline within Artificial Intelligence, and is concerned with the representation
of knowledge in symbolic form so that it can be stored and manipulated on a computer. This article surveys that part of KR
that is concerned with the representation of space and time, with particular reference to the use of such representations
in geographical information science.
相似文献
| Antony GaltonEmail: |
3.
This paper presents an examination of the timescale of phase transition behaviour of a series of salts known to cause damage
to wall paintings and other cultural property. The rate of deliquescence and crystallisation of single salts (nitromagnesite
and halite) under different RH regimes, and the extent to which this was affected when mixed with other salts (niter, nitratite
and gypsum), was investigated. The study was conducted using simple conventional techniques (mass measurements over time)
and also using an innovative new method: timelapse video imaging with online data annotation. The results demonstrate the
synergy gained from combining video imaging with environmental data in reference to time in the study of salt phase changes:
where it revealed new information concerning the kinetics of deliquescence and crystallisation. The implications of these
results for the implementation of environmental control measures within historic buildings are discussed.
相似文献
| Alison SawdyEmail: |
4.
Dorian Speakman 《Natural Hazards》2008,44(1):111-127
A vulnerability index for the Fire Service in the UK has been designed to identify vulnerable locations during episodes of
severe floods. Taking recent case studies with the UK Fire Service, the patterns of vulnerability, in terms of demand on time
and resources, can be explained by investigating the environmental causes and their interaction with the adaptive capacity
of the response agencies.
相似文献
| Dorian SpeakmanEmail: |
5.
Melt inclusion formation mechanisms and compositional effects in high-An feldspar and high-Fo olivine in anhydrous mafic silicate liquids 总被引：1，自引：1，他引：0
Important aspects of melt inclusion formation and potential compositions effects have been addressed through a series of experiments using anorthite/fosterite saturated anhydrous mafic liquids. Experimental charges were cooled from 1,300 to 1,230 and 1,210°C at rates of 1–10°/min followed by 0–24 h isothermal periods. Hopper and skeletal crystal morphologies with variable degrees of completeness developed during the cooling period. Planar overgrowth of these textures during isothermal periods led to the formation of inclusions, the majority of which formed after 6 h of isothermal run time. We suggest that the change in morphologies is related to a decrease in growth rates and changes in dominant growth mechanisms. In general, inclusion compositions were uniform and similar to the host glass, indicating that with the isothermal times required for most inclusions to form, a boundary layer was not entrapped that could be detected within the limits of our analyses.
相似文献
| Edward KohutEmail: Phone: +1-541-7373023Fax: +1-541-7371200 |
| Roger L. NielsenEmail: Phone: +1-541-7371235 |
6.
Giorgio Hadi Curti 《GeoJournal》2009,74(3):201-208
Ostensibly, subtitles in films serve as linguistic approximations of meaning. Expectedly then, much of the debate surrounding
subtitling has been concerned with representational accuracy, fidelity and authenticity. In this article I argue that by encountering
subtitles as affective bodily expressions, as opposed to approximate representations of pre-existent meanings or intentions,
filmic experiences may be(come) transformed and differently transformational. As a result, meaning and accuracy in subtitles
as superimposed signifiers or static representations become secondary to subtitles as spatially affective- and expressive-movements
intimately part of filmic scapes. The creative use of subtitling in Bekmambetov’s Russian language film Night Watch (Nochnoy dozor; 2006 [2004]) is discussed.
相似文献
| Giorgio Hadi CurtiEmail: |
7.
Catherine Hesse-Swain 《GeoJournal》2006,66(3):257-272
People living in the northeast of Thailand interchangeably label themselves and are labelled by others as Isan, Thai Isan,
Lao Isan, Thai or Lao, depending on the ethnic, political, social or familial nuances of any given situation. I use the term
Lao Isan to refer specifically to Isan people of Lao origin or ethnicity. Lao Isan are subject to complex and often competing notions
of Isan-ness, Lao-ness and Thai-ness by insiders and outsiders. Using data derived from an ethnographic study of popular Thai television and Lao Isan youth (aged
17–25) living in the city of Khon Kaen and the town of Mahasarakham in northeast Thailand in 2002, this paper explores contemporary
and co-existing interpretations of Isan identity or Khwampenisan among Lao Isan youth in relation to self-image and connections with national understandings of physical beauty as they are
perpetuated in Thai-produced television programs.
相似文献
| Catherine Hesse-SwainEmail: |
8.
Predicting environmental conditions to minimise salt damage at the Tower of London: a comparison of two approaches 总被引：1，自引：0，他引：1
Clifford A. Price 《Environmental Geology》2007,52(2):369-374
The paper compares the results of two studies of salt damage at the Wakefield Tower, Tower of London. The first, in 1993,
was based on semi-quantitative salt analysis and hygroscopicity measurements. The second was based on quantitative analysis
and a thermodynamic model, ECOS. Both studies aimed to predict environmental conditions that would minimise salt damage to
the interior stonework. Their predictions are markedly different, and this paper examines the reasons for the differences.
It is shown that hygroscopicity alone is not a reliable indicator of crystallisation from mixed salt solutions.
相似文献
| Clifford A. PriceEmail: |
9.
Space Physics Interactive Data Resource—SPIDR 总被引：1，自引：0，他引：1
Mikhail Zhizhin Eric Kihn Rob Redmon Dmitry Medvedev Dmitry Mishin 《Earth Science Informatics》2008,1(2):79-91
SPIDR (Space Physics Interactive Data Resource) is a standard data source for solar-terrestrial physics, functioning within
the framework of the ICSU World Data Centers. It is a distributed database and application server network, built to select,
visualize and model historical space weather data distributed across the Internet. SPIDR can work as a fully-functional web-application
(portal) or as a grid of web-services, providing functions for other applications to access its data holdings.
相似文献
| Mikhail ZhizhinEmail: |
10.
This paper describes an application of the geographic information system (GIS) technology to a ground stability assessment
in the karst area of Dzerzhinsk, Russia. In the stability analysis, the groundwater level changes in the karst aquifer could
cause suffosion sinkholes when the gravitational force was greater than the soil strength. The GIS technology was used to
combine various data and to delineate the zones of potential gravitational collapse and suffosion collapse in the area.
相似文献
| V. V. TolmachevEmail: |
11.
Said Ettazarini 《Environmental Geology》2006,50(6):919-929
This study takes the groundwater of the Moroccan limestone aquifer of Oum Er-Rabia as an example of statistical and cartographical approaches in water resources management. Statistical analyses based on frequency distribution and PCA methods revealed the homogeneity of waters with the existence of abnormal points and have helped to assess correlations between the studied variables. The mapping approach illustrated that waters are influenced by the lithology of the surrounding rocks and are of Ca–Mg–HCO3, Ca–Mg–Cl–SO4, and mixed types according to the Piper classification. The quality of water is of high to medium, north of the basin, but it is of medium to bad, NE and south, due to excessive contents of chloride, sulfate and nitrate. According to the US Salinity Laboratory classification, water used for irrigation in the eastern and the southern parts of the basin should take into consideration the drainage conditions, the nature of plants and the addition of gypsum doses.
相似文献
| Said EttazariniEmail: Phone: +212-66-407610 |
12.
Igor Vojnovic 《GeoJournal》2007,69(4):271-300
Throughout the 20th century, government in the U.S. has gone through significant changes; initially responding to the disorder
of early capitalism, and later, to the economic crisis of the 1970s. This article will explore the changes in the U.S. political
landscape over the last century, as well as the recent rise of neo-liberalism. In addition, with the analysis of the model
laissez-faire municipal government, the City of Houston, the article will illustrate how the basic weaknesses of neoliberalism
at the national level are also evident at the local scale of government.
相似文献
| Igor VojnovicEmail: |
13.
A commented translation of the paper by C.W. Correns and W. Steinborn on crystallization pressure 总被引：1，自引：0，他引：1
Crystallization of salts is recognized to be a major factor of the degradation of porous materials such as stone and concrete.
On the theoretical side, there is now general acceptance about the thermodynamic origin of this phenomenon. However, on the
experimental side, there are only scarce quantitative data. In this respect, the reference work par excellence is that of Correns (Discuss Faraday Soc 5:267–271, 1949) who shows a good correlation between calculated and measured crystallization pressures. However, concerns about both the
thermodynamic derivation and the experimental conditions raise the question about why Correns could have obtained such a good
correlation. This issue is discussed extensively in this paper which is organized as a commented translation of a former paper
by Correns, co-authored by Steinborn, and that is much richer in experimental details.
相似文献
| Robert J. FlattEmail: |
14.
The aim of this paper is to use an economic framework to derive decision making rules for river basin management with a focus on groundwater resources. Using an example from northern Nigeria, the paper provides an example of how decision making for sustainable water resources management may be facilitated by comparing net benefits and costs across a river basin. It is argued that economic tools can be used to assess the value of water resources in different uses, identify and analyze management scenarios, and provide decision rules for the sustainable use and management of surface and ground water resources in the region.
相似文献
| Gayatri AcharyaEmail: |
15.
Nicolas Trcera Delphine Cabaret Stéphanie Rossano François Farges Anne-Marie Flank Pierre Lagarde 《Physics and Chemistry of Minerals》2009,36(5):241-257
X-ray absorption spectroscopy at the Mg K-edge is used to obtain information on magnesium environment in minerals, silicate and alumino-silicate glasses. First-principles
XANES calculations are performed for minerals using a plane-wave density functional formalism with core-hole effects treated
in a supercell approach. The good agreement obtained between experimental and theoretical spectra provides useful information
to interpret the spectral features. With the help of calculation, the position of the first peak of XANES spectra is related
to both coordination and polyhedron distortion changes. In alumino-silicate glasses, magnesium is found to be mainly 5-fold
coordinated to oxygen whatever the aluminum saturation index value. In silicate glasses, magnesium coordination increases
from 4 in Cs-, Rb- and K-bearing glasses to 5 in Na- and Li-bearing glasses but remains equal as the polymerization degree
of the glass varies. The variation of the C feature (position and intensity) is strongly related to the alkali type providing
information on the medium range order.
相似文献
| Stéphanie RossanoEmail: |
16.
In a media saturated world of globalization, information flow and knowledge economies, an interesting paradox exists: geographic
literacy appears to be on the decline while geographic information is on the rise. In this introduction to a collection of
essays on geographies of the media, we explore this paradox and use Baudrillard’s (1994) work on Simulacra and Simulation to argue that increased mediated information does not produce more meaning, but rather leads to a catastrophe of meaning
and the medium. Drawing from McLuhan’s axiom, “the medium is the message,” we posit that with more mediated information there
is less meaningful information and as such we need to address geographic media literacy as a primary mode through which to
address geographic literacy.
相似文献
| Jim CraineEmail: |
17.
Sarah F. Ives 《GeoJournal》2009,74(3):245-255
Using a discussion of South African soap operas, I will place the idea of visuality in a discourse analysis that incorporates
a feminist epistemological lens, or an epistemology that integrates reflexivity and an acknowledgment of the dialogic nature
of visual media. Through this discussion, I will examine the possibilities that dialogism provides for unpacking and exploring
the politics of imperfect translation between the visual and the textual. These methodological interventions, I argue, will
help enrich discussions of the visual’s role in the contested realm of geographic imaginations and move beyond the distanced
position of the masculine gaze.
相似文献
| Sarah F. IvesEmail: |
18.
Anthony John Christopher 《GeoJournal》2006,67(2):123-136
The pattern of Church of England dioceses has evolved over a period of 1,400 years. It reflects the practical response of
the Church to the changing political and demographic patterns of the country. No ideal size and form of diocese was ever devised
and few systematic attempts were made to achieve a degree of equity between them. The constitutional link between state and
church has inhibited change for the last 80 years, although society has changed significantly. Nevertheless, rapid constitutional
reforms, especially in the House of Lords, may be reflected in ecclesiastical reorganisation of the dioceses.
相似文献
| Anthony John ChristopherEmail: |
19.
Indigenous people often exclusively depend on the natural resources available within the ecosystems where they live, and commonly
manage their resources sustainably. They have developed, and continue to develop indigenous knowledge systems which encompass
sustainable management of natural resources. This study compares indigenous knowledge of natural resource management developed
by two different communities in two different environments—Maori in the temperate environment in New Zealand and Dusun in
the tropical environment in Brunei Darussalam, and comparatively evaluates the role of indigenous knowledge in sustainable
resource management in three categories of knowledge such as spatial and seasonal distribution of natural resources, sustainable
harvesting, and habitat management. The comparison reveals that despite the differences in environment and the great geographical
distance between the two communities, there are remarkable similarities between the two knowledge systems in concepts, principles,
strategies and technologies used in natural resource management.
相似文献
| Rohana UlluwishewaEmail: |
20.
The advent of the Virtual Observatory has begun an evolution in the space physics data environment. A number of nascent and
discipline specific Virtual Observatories have started to emerge with an emphasis on data search and retrieval. As this new
data environment takes shape an emphasis will be placed on interdisciplinary communication in attempts to address large scale
and global problems. To this end we formulate the development of a query language to facilitate Virtual Observatory to Virtual
Observatory communication. Furthermore, we outline the goals of such a language, how it would work and how existing community
efforts can be leveraged to speed the development of this query language.
相似文献
| T.W. NarockEmail: |