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991.
Shannon O’Lear 《GeoJournal》2005,64(4):297-306
The objective of this paper is to engage constructively with literature on armed conflict and resources in order to draw attention
both to assumptions that hinder a more accurate or useful understanding of natural resources and their role in territorial
conflict as well as to aspects of this field of research that merit further work. In much of the literature on resource conflict,
territorial aspects are either implicitly or explicitly tied to resource conflict largely through the assumption that the
value of territory is intrinsic. Little of the literature attempts to advance theory, specifically, either on the particular
role of resources or on the meaning and objectives of conflict beyond a one-dimensional objective of maintaining or securing
control of territory. The paper considers themes of resource scarcity and resource abundance in conflict. A third section
focuses on an analysis both of natural resource databases and of conflict databases (both international and civil) which emphasizes
problematic results of blending these databases to demonstrate correlations.
UIUC territorial conflict management workshop 相似文献
992.
Data recorded by a seismic network deployed the day after the 2004 Mid Niigata Prefecture Earthquake (M6.8) in central Japan are used to determine the major source faults responsible for the mainshock and major aftershocks. Using this high-resolution seismic data, three major source faults are identified: two parallel faults dipping steeply to the west located 5 km apart, and the other dipping eastward and oriented perpendicular to the west-dipping faults. The analysis also reveals that the lateral variation in seismic velocity observed at the surface extends to a depth of 15 km, encompassing the source area of the mainshock. This strong heterogeneity of the crust, related to the complex geological and tectonic evolution of the area, is considered to be responsible for the prominent aftershock activity following the 2004 Niigata event. 相似文献
993.
An approach for GIS-based statistical landslide susceptibility zonation—with a case study in the Himalayas 总被引:14,自引:1,他引:14
Ashis K. Saha Ravi P. Gupta Irene Sarkar Manoj K. Arora Elmar Csaplovics 《Landslides》2005,2(1):61-69
Landslide susceptibility zonation (LSZ) is necessary for disaster management and planning development activities in mountainous regions. A number of methods, viz. landslide distribution, qualitative, statistical and distribution-free analyses have been used for the LSZ studies and they are again briefly reviewed here. In this work, two methods, the Information Value (InfoVal) and the Landslide Nominal Susceptibility Factor (LNSF) methods that are based on bivariate statistical analysis have been applied for LSZ mapping in a part of the Himalayas. Relevant thematic maps representing various factors (e.g., slope, aspect, relative relief, lithology, buffer zones along thrusts, faults and lineaments, drainage density and landcover) that are related to landslide activity, have been generated using remote sensing and GIS techniques. The LSZ derived from the LNSF method, has been compared with that produced from the InfoVal method and the result shows a more realistic LSZ map from the LNSF method which appears to conform to the heterogeneity of the terrain. 相似文献
994.
The conditions for the fragmentation of the baryonic component during mergers of dark matter halos in the early Universe are studied. We assume that the baryonic component undergoes a shock compression. The characteristic masses of protostellar molecular clouds and the minimum masses of protostars originating in these clouds decrease with increasing halo mass. This may indicate that the initial stellar mass function in more massive galaxies was shifted towards lower masses during the initial stages of their formation. This would result in an increase in the number of stars per unit mass of the halo, i.e., in an increase in the efficiency of star formation. 相似文献
995.
Analyses of the patterns of national population change have been influenced by the US experience where major differences between a older north and a newer south are prominent in many studies. The current paper argues that these perspectives overlook some inertia in the pattern of population and jobs. Drawing upon US and European experience the paper explores the pattern of change in Australia. There it finds that population has favoured newer locations but that gains in share of national population have not been large. At the same time some of the older regions have maintained population share, or at worst recorded small declines. That broad insight is enriched by sectoral analysis where it is clear that only the retail sector has experienced the large gains in new regions; employment change in other sectors showed the links with population change are weak. The paper concludes that simple notions of new region population and employment gains are oversimplified and overlook the substantial development around established centres. In particular it is possible that the old regions are re-structuring their spatial form and spilling over statistical boundaries and so actually maintaining established role in national networks. 相似文献
996.
V. I. Fel’dman L. V. Sazonova V. V. Milyavskii T. I. Borodina S. N. Sokolov A. Z. Zhuk 《Izvestiya Physics of the Solid Earth》2006,42(6):477-480
The shock metamorphism of schist consisting of garnet, biotite, quartz, and plagioclase is studied under shock wave loading of a sample in steel recovery ampoules of plane geometry. A maximum shock pressure was reached during several circulations of waves in the sample (stepwise shock compression) and varied within the range 19–52 GPa. The recovered samples were examined by the methods of scanning electron microscopy and microprobe and X-ray phase analysis. The results were compared with natural impactites and with shock-induced alterations in minerals loaded by a spherical convergent wave. It is established that, given a plane geometry of loading (stepwise shock compression), solid-state transformations at the lattice level (migration of chemical elements and formation of shock thermal aggregates) are not observed in all of the studied minerals, in contrast to natural impact processes and spherical geometry experiments. Under the conditions of our experiments, minerals melt at higher pressures than in the case of natural impact processes and spherical geometry experiments. However, for each mineral studied, the mechanical strain patterns at close shock pressures are, on the whole, the same for all of the aforementioned three variants of shock wave loading. 相似文献
997.
V. P. Antonova K. E. Dungenbaeva A. V. Zalizovskii A. S. Inchin S. V. Kryukov V. M. Somsikov Yu. M. Yampol’skii 《Geomagnetism and Aeronomy》2006,46(1):101-109
The singularities of the wave disturbance spectra of the nonequilibrium atmosphere in the range of acoustic gravity waves (AGWs) have been analyzed. Using the dispersion ratio for AGWs in the nonequilibrium atmosphere, it has been established that the spectra in the daytime and nighttime hours are different and this difference, caused by a nonequilibrium spectrum sensitivity to atmospheric temperature, can reach several percent in certain atmospheric regions. For the spectrum of the equilibrium model of the atmosphere, the difference between the daytime and nighttime spectra makes up several fractions of percent. As a result of the spectral treatment of variations in pressure and intensity of cosmic rays (CRs), it has been found out that the daytime AGW spectrum is higher-frequency than the nighttime spectrum. A comparison of the theoretical calculations of the AGW spectrum with observations has made it possible to distinguish the effect of nonequilibrium in the AGW spectral composition. 相似文献
998.
Yu. B. Bashkuev V. P. Mel’chinov M. G. Dembelov L. Kh. Angarkhaeva D. G. Buyanova V. A. Borsoev 《Geomagnetism and Aeronomy》2006,46(4):507-516
Result of the measurements of the cryolithic zone electrical properties by the radio impedance sounding method are presented. The surface impedance and geoelectric section of the Arctic permafrost have been determined. The experiments have been performed near Cherskii in the continental zone. The surface wave attenuation function is considered. The accuracy of the surface wave field calculations at high latitudes has been estimated based on the local electrical characteristics of the underlying cryogenic medium. The effect of the Arctic Ocean on the operating zone of navigation and communication facilities in the kilometer wave band has been experimentally estimated. 相似文献
999.
M. V. Popov A. D. Kuz’min O. M. Ul’yanov A. A. Deshpande A. A. Ershov V. V. Zakharenko V. I. Kondrat’ev S. V. Kostyuk B. Ya. Losovskiĭ V. A. Soglasnov 《Astronomy Reports》2006,50(7):562-568
The results of simultaneous multifrequency observations of giant radio pulses from the Crab pulsar, PSR B0531+21, at 23, 111, and 600 MHz are presented and analyzed. Giant pulses were detected at a frequency as low as 23 MHz for the first time. Of the 45 giant pulses detected at 23 MHz, 12 were identified with counterparts observed simultaneously at 600 MHz. Of the 128 giant pulses detected at 111 MHz, 21 were identified with counterparts observed simultaneously at 600 MHz. The spectral indices for the power-law frequency dependence of the giant-pulse energies are from ?3.1 to ?1.6. The mean spectral index is ?2.7 ± 0.1 and is the same for both frequency combinations (600–111 MHz and 600–23 MHz). The large scatter in the spectral indices of the individual pulses and the large number of unidentified giant pulses suggest that the spectra of the individual giant pulses do not actually follow a simple power law. The observed shapes of the giant pulses at all three frequencies are determined by scattering on interstellar plasma inhomogeneities. The scatter-broadening of the pulses and its frequency dependence were determined as τ sc = 20(ν/100)?3.5±0.1 ms, where frequency ν is in MHz. 相似文献
1000.
The complex active region NOAA 9672 is studied when it was near the central meridian, from October 21–26, 2001. At that time, there was an emergence of new magnetic flux, with the ongoing formation of a filament. The dynamics of the magnetic field are studied in order to search for their possible manifestations in the filament structure, using SOHO MDI magnetograms, SOHO EIT and TRACE filtergrams in the 171 Å line, and Hα filtergrams available via the Internet. Our earlier conclusion that filaments form at the boundaries of supergranules near polarity-inversion lines is confirmed. The conclusion of Chae that sinistral filaments have positive magnetic helicity is also confirmed. New information about magnetic-field decay processes is obtained. The direction of motion of the magnetic poles and their relative positions suggest that the axial field of a filament forms as a result of either reconnection of cancelling magnetic poles, or emergence of horizontal magnetic-flux tubes. 相似文献