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101.
Application of the Ordered Weighted Averaging (OWA) method to the Caspian Sea conflict 总被引:1,自引:0,他引:1
Hojjat Mianabadi Majid Sheikhmohammady Erik Mostert Nick Van de Giesen 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(6):1359-1372
This study proposes a promising allocation mechanism of the Caspian Sea natural resources, which are presently shared among five countries. To date, these nations have been unable to reach an allocation agreement. We apply a methodology to propose the most appropriate solution under different risk attitudes of the states. This research is different from other studies regarding the Caspian Sea negotiations in that it employs risk-based fuzzy multi attribute decision making methods for simulating the risk attitudes or optimism/pessimism degrees of the decision makers. The ordered weighted averaging (OWA) approach, which considers the optimism/pessimism degree quantitatively, is used to take into account the effects of different risk attitudes of the negotiators on the final outcome. We demonstrate how one could obtain a range of alternatives under different multi attribute and risk attitudes. The induced OWA (IOWA) method is also used to determine the relative power of these states bordering the Caspian Sea by considering several attributes, including different risk attitudes of agents. Results indicate that taking into account the risk attitude (prone, neutral, averse) of the states can affect the overall ranking of the proposed solutions. The findings from this study may facilitate negotiation regarding the most preferred allocation mechanism for the Caspian Sea. 相似文献
102.
Marc Rütschlin Johannes H. Cloete Iain M. Mason Keith D. Palmer 《Journal of Applied Geophysics》2007,62(4):354-360
A new measurement technique enables the complex dielectric properties of the geological strata comprising the UG1–UG2 (Upper Group 1–Upper Group 2) unit of the Bushveld Complex in South Africa to be determined with unprecedented detail at radio frequencies (RF). Results of non-destructive laboratory measurements of representative diamond drill core samples from the UG1–UG2 unit are presented at 25 MHz. These data establish that the UG1 and UG2 chromitite layers are embedded in rock strata (norite, pyroxenite and anorthosite) which are translucent in the HF spectral band, whereas the chromitite layers themselves exhibit significant velocity contrast, making them good radar reflectors. The data presented here is useful for calibration of the radar system, and for predicting the range and resolution performance of borehole radars operating in both the hanging and footwalls of the economically important platiniferous UG2 reef. 相似文献
103.
William D. Robertson James W. Roy Susan J. Brown Dale R. Van Stempvoort Greg Bickerton 《Ground water》2014,52(1):63-70
Monitoring of a well‐defined septic system groundwater plume and groundwater discharging to two urban streams located in southern Ontario, Canada, provided evidence of natural attenuation of background low level (ng/L) perchlorate (ClO4?) under denitrifying conditions in the field. The septic system site at Long Point contains ClO4? from a mix of waste water, atmospheric deposition, and periodic use of fireworks, while the nitrate plume indicates active denitrification. Plume nitrate (NO3?‐N) concentrations of up to 103 mg/L declined with depth and downgradient of the tile bed due to denitrification and anammox activity, and the plume was almost completely denitrified beyond 35 m from the tile bed. The ClO4? natural attenuation occurs at the site only when NO3?‐N concentrations are <0.3 mg/L, after which ClO4? concentrations decline abruptly from 187 ± 202 to 11 ± 15 ng/L. A similar pattern between NO3?‐N and ClO4? was found in groundwater discharging to the two urban streams. These findings suggest that natural attenuation (i.e., biodegradation) of ClO4? may be commonplace in denitrified aquifers with appropriate electron donors present, and thus, should be considered as a remediation option for ClO4? contaminated groundwater. 相似文献
104.
Michael O. Garcia Ken H. Rubin Marc D. Norman J. Michael Rhodes David W. Graham David W. Muenow Khalil Spencer 《Bulletin of Volcanology》1998,59(8):577-592
Samples of basalt were collected during the Rapid Response cruise to Loihi seamount from a breccia that was probably created
by the July to August 1996 Loihi earthquake swarm, the largest swarm ever recorded from a Hawaiian volcano. 210Po–210Pb dating of two fresh lava blocks from this breccia indicates that they were erupted during the first half of 1996, making
this the first documented historical eruption of Loihi. Sonobuoys deployed during the August 1996 cruise recorded popping
noises north of the breccia site, indicating that the eruption may have been continuing during the swarm. All of the breccia
lava fragments are tholeiitic, like the vast majority of Loihi's most recent lavas. Reverse zoning at the rim of clinopyroxene
phenocrysts, and the presence of two chemically distinct olivine phenocryst populations, indicate that the magma for the lavas
was mixed just prior to eruption. The trace element geochemistry of these lavas indicates there has been a reversal in Loihi's
temporal geochemical trend. Although the new Loihi lavas are similar isotopically and geochemically to recent Kilauea lavas
and the mantle conduits for these two volcanoes appear to converge at depth, distinct trace element ratios for their recent
lavas preclude common parental magmas for these two active volcanoes. The mineralogy of Loihi's recent tholeiitic lavas signify
that they crystallized at moderate depths (∼8–9 km) within the volcano, which is approximately 1 km below the hypocenters
for earthquakes from the 1996 swarm. Taken together, the petrological and seismic evidence indicates that Loihi's current
magma chamber is considerably deeper than the shallow magma chamber (∼3–4 km) in the adjoining active shield volcanoes.
Received: 21 August 1997 / Accepted: 15 February 1998 相似文献
105.
Effect of common point selection on coordinate transformation parameter determination 总被引:2,自引:0,他引:2
The use of satellite positioning techniques commonly requires a transformation from a Conventional Terrestrial coordinate
system to a Geodetic coordinate system, or vice versa. For such a transformation, the main problem is the determination of
transformation parameters between these coordinate systems. The transformation parameters are estimated by a least-squares
process using “common” points, i.e., those points whose coordinates are known in both systems. Therefore, the precision of
so estimated transformation parameters is closely related to certain characteristics of the common points. In this contribution,
we have formulated some theoretical relations between the transformation parameters and the number and the distribution of
common points, and corroborated the theoretical results numerically, using a simulated geodetic network. 相似文献
106.
Laboratory flume experiments were carried out to evaluate the effect of particle density on bedload transport of sand‐sized particles and the effect of a suspended load of clay particles (kaolinite) on bedload transport of sand‐sized particles in rill flow conditions. Three materials in the range 400–600 µm were selected to simulate bedload transport of primary particles and aggregates: sand (2650 kg/m3), crushed brick (2450 kg/m3) and anthracite (1300–1700 kg/m3). In the two first experiments, two different methods were applied to determine bedload transport capacity of coarse particles for various conditions of flow discharge (from 2 to 15 L/min) and slope (2.2, 3 and 4%). In the third experiment, clear water was replaced with kaolinite–water mixture and bedload transport capacity of crushed brick particles was determined for a 4% slope and different concentrations of kaolinite (0, 7, 41 and 84 g/L). The results showed that bedload transport increased significantly with the decrease in particle density but the effect of particle density on transport rates was much less important than flow discharge. Velocity measurements of clear flow, flow mixed with coarse particles and coarse particles confirmed the existence of a differentiation between suspended load and bedload. In these experimental conditions, suspended load of kaolinite did not affect bedload rates of crushed brick particles. Three transport capacity formulae were tested against observed bedload rates. A calibration of the Foster formula revealed that the shear stress exponent should be greater than 1.5. The Low and the Govers unit stream power (USP) equations were then evaluated. The Low equation was preferred for the prediction of bedload rates of primary particles but it was not recommended in the case of aggregates of low density because of the limited experimental conditions applied to derive this equation. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
107.
U-series systematics as well as Sr isotopes were measured on young seamount lavas from the Pitcairn hotspot collected during the Polynaut cruise. The combined U-series and Sr isotope data reveal typical mixing relationships between two endmembers. One typical ‘plume’ endmember with radiogenic 87Sr/86Sr and relatively low 230Th/238U and a ‘lithosphere’ endmember with less radiogenic 87Sr/86Sr and relatively larger 230Th/238U. Remarkably, all the lavas, except for a few arguably older samples, are characterized by 226Ra deficits relative to 230Th. On the basis of water content and trace element systematics, we argue that this is due to melting in the presence of phlogopite, which is only stable at lithosphere temperatures. A melting model including the diffusive exchange of elements among phlogopite, garnet and melt is used to constrain melting conditions of the lithosphere. These unusual 226Ra–230Th signatures can be explained by relatively slow melting rates at low matrix porosity. Our model also demonstrates that the effective partitioning behavior is dependent on the melting rate. A simple thermal model for lithosphere heating and melting is in good agreement with predicted melting rates. 相似文献
108.
The Arica Elbow region represents that part of Andean South America where the azimuth of the strike of the Peru-Chile trench changes from 150° to 190°. The area under study is roughly bounded by latitudes 17 °S and 23 °S, The shape of the Wadati-Benioff zone was studied in terms of the distribution of ISC hypocentres dated between 1964 and 1993. A system of 22 vertical cross-sections, perpendicular to the trench axis, and a map of epicentres was used to derive the detailed shape of the Wadati-Benioff zone of the presently descending slab. The distribution of earthquake foci indicates a fingerlike shape of the lower part of the Wadati-Benioff zone beneath the aseismic gap. The slab length shows small changes around 350 km in the northern sections, pronounced length oscillations between 350 and 750 km in the neighbouring central sections and a constant value of 650 km in the southern sections. The dip and thickness of the Wadati-Benioff zone are practically constant in all sections. Fault plane solutions, separated spatially into three zones, were used to estimate the state of stress in the slab. 相似文献
109.
110.