Critical network infrastructure analysis: interdiction and system flow   总被引：5，自引：1，他引：4  

Alan T. Murray  Timothy C. Matisziw  Tony H. Grubesic 《Journal of Geographical Systems》2007,9(2):103-117

Effective management of critical network infrastructure requires the assessment of potential interdiction scenarios. Optimization approaches have been essential for identifying and evaluating such scenarios in networked systems. Although a primary function of any network is the distribution of flow between origins and destinations, the complexity and difficulty of mathematically abstracting interdiction impacts on connectivity or flow has been a challenge for researchers. This paper presents an optimization approach for identifying interdiction bounds with respect to connectivity and/or flow associated with a system of origins and destinations. Application results for telecommunications flow are presented, illustrating the capabilities of this approach.

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Alan T. Murray (Corresponding author)Email:

Timothy C. MatisziwEmail:

Tony H. GrubesicEmail:

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A Textural Record of Solidification and Cooling in the Skaergaard Intrusion, East Greenland   总被引：2，自引：0，他引：2  

Holness  Marian B.; Tegner  Christian; Nielsen  Troels F. D.; Stripp  Gemma; Morse  Stearns A. 《Journal of Petrology》2007,48(12):2359-2377

The clinopyroxene–plagioclase–plagioclase dihedralangle, _cpp, in gabbroic cumulates records the time-integratedthermal history in the sub-solidus and provides a measure oftextural maturity. Variations in _cpp through the Layered Seriesof the Skaergaard intrusion, East Greenland, demonstrate thatthe onset of crystallization of clinopyroxene (within LZa),Fe–Ti oxides (at the base of LZc) and apatite (at thebase of UZb) as liquidus phases in the bulk magma is recordedby a stepwise increase in textural maturity, related to an increasein the contribution of latent heat to the total heat loss tothe surroundings and a reduction in the specific cooling rateat the crystallization front of the intrusion. The onset ofboth liquidus Fe–Ti oxide and apatite crystallizationis marked by a transient increase in textural maturity, probablylinked to overstepping before nucleation. Textural maturationat pyroxene–plagioclase–plagioclase triple junctionseffectively ceases in the uppermost parts of the Layered Seriesas a result of the entire pluton cooling below the closure temperaturefor dihedral angle change, which is 1075°C. Solidificationof the Layered Series of the Skaergaard intrusion occurred viathe upwards propagation of a mush zone only a few metres thick. KEY WORDS: magma; partial melting; asthenosphere; olivine; mantle  相似文献   

An upgraded and integrated large-volume high-pressure facility at the GeoSoilEnviroCARS bending magnet beamline of the Advanced Photon Source     

Tony Yu  Yanbin Wang  Mark L. Rivers  Stephen R. Sutton 《Comptes Rendus Geoscience》2019,351(2-3):269-279

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The role of site effects in the comparison between code provisions and the near field strong motion of the Emilia 2012 earthquakes   总被引：1，自引：1，他引：0  

Maria Rosaria Gallipoli  Leonardo Chiauzzi  Tony Alfredo Stabile  Marco Mucciarelli  Angelo Masi  Carmine Lizza  Luigi Vignola 《Bulletin of Earthquake Engineering》2014,12(5):2211-2230

A damaging seismic sequence hit a wide area mainly located in the Emilia-Romagna region (Northern Italy) during 2012 with several events of local magnitude \(\hbox {M}_\mathrm{l} \ge 5\) , among which the \(\hbox {M}_\mathrm{l}\) 5.9 May 20 and the \(\hbox {M}_\mathrm{l}\) 5.8 May 29 were the main events. Thanks to the presence of a permanent accelerometric station very close to the epicentre and to the temporary installations performed in the aftermath of the first shock, a large number of strong motion recordings are available, on the basis of which, we compared the recorded signals with the values provided by the current Italian seismic regulations, and we observed several differences with respect to horizontal components when the simplified approach for site conditions (based on Vs30 classes) is used. On the contrary, when using the more accurate approach based on the local seismic response, we generally obtain a much better agreement, at least in the frequency range corresponding to a quarter wavelength comparable with the depth of the available subsoil data. Some unresolved questions still remain, such as the low frequency behaviour ( \(<\) 1 Hz) that could be due either to complex propagation at depth larger than the one presently investigated or to near source effects, and the behaviour of vertical spectra whose recorded/code difference is too large to be explained with the information currently available.  相似文献   

Performance of the health facilities during the 2012 Emilia (Italy) earthquake and analysis of the Mirandola hospital case study     

Angelo Masi  Giuseppe Santarsiero  Maria Rosaria Gallipoli  Marco Mucciarelli  Vincenzo Manfredi  Alberto Dusi  Tony Alfredo Stabile 《Bulletin of Earthquake Engineering》2014,12(5):2419-2443

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Robust identification of periodic behavior in the time dynamics of short seismic series: the case of seismicity induced by Pertusillo Lake,southern Italy     

Luciano Telesca  Alessandro Giocoli  Vincenzo Lapenna  Tony Alfredo Stabile 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(5):1437-1446

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Catchment response to lava damming: integrating field observation,geochronology and landscape evolution modelling          下载免费PDF全文

Wouter van Gorp  Jeroen M. Schoorl  Arnaud J. A. M. Temme  Tony Reimann  Jan R. Wijbrans  Darrel Maddy  Tuncer Demir  Tom Veldkamp 《地球表面变化过程与地形》2016,41(11):1629-1644

Combining field reconstruction and landscape evolution modelling can be useful to investigate the relative role of different drivers on catchment response. The Geren Catchment (~45 km²) in western Turkey is suitable for such a study, as it has been influenced by uplift, climate change and lava damming. Four Middle Pleistocene lava flows (⁴⁰Ar/³⁹Ar‐ dated from 310 to 175 ka) filled and dammed the Gediz River at the Gediz–Geren confluence, resulting in base‐level fluctuations of the otherwise uplift‐driven incising river. Field reconstruction and luminescence dating suggest fluvial terraces in the Geren Catchment are capped by Middle Pleistocene aggradational fills. This showed that incision of the Geren trunk stream has been delayed until the end of MIS 5. Subsequently, the catchment has responded to base‐level lowering since MIS 4 by 30 m of stepped net incision. Field reconstruction left us with uncertainty on the main drivers of terrace formation. Therefore, we used landscape evolution modelling to investigate catchment response to three scenarios of base‐level change: (i) uplift with climate change (rainfall and vegetation based on arboreal pollen); (ii) uplift, climate change and short‐lived damming events; (iii) uplift, climate and long‐lived damming events. Outputs were evaluated for erosion–aggradation evolution in trunk streams at two different distances from the catchment outlet. Climate influences erosion–aggradation activity in the catchment, although internal feedbacks influence timing and magnitude. Furthermore, lava damming events partly control if and where these climate‐driven aggradations occur. Damming thus leaves a legacy on current landscape evolution. Catchment response to long‐duration damming events corresponds best with field reconstruction and dating. The combination of climate and base level explains a significant part of the landscape evolution history of the Geren Catchment. By combining model results with fieldwork, additional conclusions on landscape evolution could be drawn. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

Consistent Estimates of Tsunami Energy Show Promise for Improved Early Warning     

V. Titov  Y. Tony Song  L. Tang  E. N. Bernard  Y. Bar-Sever  Y. Wei 《Pure and Applied Geophysics》2016,173(12):3863-3880

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Scenarios for Community-based Approaches to Biodiversity Conservation: a case study from the Wet Tropics,Queensland, Australia     

Petina L. Pert  Kristen J. Williams  Elaine K. Harding  Tony O'Malley  Rowena A. Grace 《The Australian geographer》2010,41(3):285-306

Natural resource management approaches that deliver biodiversity conservation remain elusive, with evidence of a persistent implementation gap between biodiversity science and conservation projects. Scenarios have been identified as potentially useful in addressing the complex issues underlying this implementation gap, but have been infrequently applied to biodiversity conservation. Our paper reports on action co-research to develop, apply and assess the efficacy of scenarios within a community-based natural resource management (CBNRM) approach to biodiversity conservation at Mission Beach, a key site within the globally significant Wet Tropics bioregion. We focused on the capacity of scenarios to address the issues of contested interests and uncertainty, aiming specifically to engage the community to build a cohesive vision. The scenarios' headline messages included a projected substantial loss of habitat in coastal vegetation communities that are highly valued by all stakeholders. Our assessment identified that the use of scenarios fulfilled the intended aims, resulting in a vision for biodiversity conservation that has substantial community support. Three factors contributed to this efficacy of the scenarios: (1) the focus on threat; (2) biodiversity science integration; and (3) simplicity in presentation. Further investigation of the potential of scenarios as tools to overcome the implementation gap in biodiversity conservation is recommended.  相似文献   

Accumulation Rate Measurements at Taylor Dome, East Antarctica: Techniques and Strategies for Mass Balance Measurements in Polar Environments     

David L. Morse  Edwin D. Waddington  Hans-Peter Marshall  Tomas A. Neumann  Eric J. Steig  Jack E. Dibb  Dale P. Winebrenner  & Robert J. Arthern 《Geografiska Annaler: Series A, Physical Geography》1999,81(4):683-694

Accumulation rate measurements on the East Antarctic plateau are challenging due to both spatial and temporal variability. Annual stratigraphy is often not reliably or consistently preserved in the firn, and so accumulation cannot be determined from snow pit stratigraphy. We present a suite of accumulation rate measurements collected over several seasons at Taylor Dome, East Antarctica. We compare net accumulation results from direct burial rate measurements and β -activity firn cores along a 35 km traverse. The two methods are consistent and show that the net accumulation varies from greater than 10 cm a⁻¹ to about 1 cm a⁻¹ (ice equivalent) southwest to northeast across the dome. We map the depth of shallow radar layering to interpolate and extrapolate these point-location measurements and show that considerable variations occur over kilometer scales resulting from subtle surface topography. We also present accumulation rates estimated from concentration of the cosmogenic isotope ¹⁰Be and from activity profiles of ²¹⁰Pb. Finally, satellite passive microwave data are used to estimate spatially averaged accumulation rates on the regional to continental scale to provide a context for these local observations. We show that robust mass balance measurements in this environment must rely on spatial and/or temporal averaging.  相似文献