The Development And Application Of A Simple Methodology For Recording Rock Art Using Consumer-Grade Digital Cameras     

Jim H.  Chandler  Paul  Bryan  John G.  Fryer 《The Photogrammetric Record》2007,22(117):10-21

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Establishing the Database of Inundation Potential in Taiwan     

Albert S. Chen  Ming-Hsi Hsu  Wei-Hsien Teng  Chen-Jia Huang  Sen-Hae Yeh  Wan-Yu Lien 《Natural Hazards》2006,37(1-2):107-132

The structural measure was the major solution for flood defense in Taiwan. However, the measure is always limited to the design standard and cannot prevent the damages when floods exceed certain scale. Therefore, non-structural measures for flood mitigation are the indispensable complements to structural solutions. The study introduces the establishment of inundation potential database that provides required information for the non-structural measures in Taiwan. The database was built by numerical simulations, based on different rainfall scenarios, and has been applied by the local governments of Taiwan for land use managements, flood warning systems, emergency responses, and flood insurance programs to reduce the flood damages and impacts.  相似文献   

A diversified multiobjective GA for optimizing reservoir rule curves     

Li Chen  James McPhee  William W.-G. Yeh 《Advances in water resources》2007

The paper develops an efficient macro-evolutionary multiobjective genetic algorithm (MMGA) for optimizing the rule curves of a multi-purpose reservoir system in Taiwan. Macro-evolution is a new kind of high-level species evolution that can avoid premature convergence that may arise during the selection process of conventional GAs. MMGA enriches the capabilities of GA to handle multiobjective problems by diversifying the solution set. Simulation results using a benchmark test problem indicate that the proposed MMGA yields better-spread solutions and converges closer to the true Pareto frontier than the nondominated sorting genetic algorithm-II (NSGA-II). When applied to a real case study, MMGA is able to generate uniformly spread solutions for a two-objective problem involving water supply and hydropower generation. Results of this work indicate that the proposed MMGA is highly competitive and provides a viable alternative to solve multiobjective optimization problems for water resources planning and management.  相似文献   

XTE J1550–564: a superluminal ejection during the September 1998 outburst     

Diana Hannikainen  Duncan Campbell-Wilson  Richard Hunstead  Vince McIntyre  Jim Lovell  John Reynolds  Tasso Tzioumis  Kinwah Wu 《Astrophysics and Space Science》2001,276(1):45-48

In 1998 September, the X-ray transient XTE J1550–564 underwent amajor outburst in soft and hard X-rays, followed by a radio flare. Australian Long Baseline Array imagesobtained shortly after the peak in the radio flare showed evolving structure.The components observed have an apparent separation velocity of >2c.  相似文献   

Multiphase flow modeling with general boundary conditions and automatic phase-configuration changes using a fractional-flow approach     

Heejun Suk  Gour-Tsyh Yeh 《Computational Geosciences》2008,12(4):541-571

The multiphase flow simulator moving particle semi-implicit (MPS) method is developed based on the fractional-flow approach, originated in the petroleum engineering literature, considering the fully three-phase flow with general boundary conditions. The fractional flow approach employs water saturation, total liquid saturation, and total pressure as primary variables. Most existing models based upon fractional flow are limited to two-phase flow and specific boundary conditions. Although there appear a number of three-phase flow models, they were mostly developed using pressure-based approaches, which require variable-switch techniques to deal with phase appearance and disappearance. The use of fractional flow-based approaches in MPS makes it unnecessary to use variable-switching to handle the change of phase configurations because the water saturation, total liquid saturation, and total pressure exist throughout the solution domain regardless of whether certain phases are present or not. Furthermore, most existing fractional flow-based models consider only specific boundary conditions, usually Dirichlet-type pressure for water phase and flux-type boundary for nonaqueous phase liquid or particular combinations for individual phase. However, the present model considers general boundary conditions of ten most possible and plausible cases. The first eight cases are the combinations of the phase pressure or the phase flux of each of the three individual phases. The other two cases are the variable boundary conditions: one for water-medium interface and the other for the air-medium interface when the directions of fluxes are not known a priori. Thus, the model’s capabilities of handling general boundary conditions extend the simulators’ usefulness in the field system.  相似文献   

Geochemistry of hydrothermal deposits from Loihi submarine volcano,Hawaii     

Eric H. De Carlo  Gary M. McMurtry  Hsueh-Wen Yeh 《Earth and Planetary Science Letters》1983

Dredging across the northeast rim of the summit crater of Loihi Seamount recovered several morphologically similar but chemically and mineralogically distinct hydrothermal deposits encrusting the surface of fresh pillow lava talus. The multicolored deposits suggest a precipitation sequence that may be controlled by an oxidation-reduction gradient in which smectite ranging in composition from Fe-montmorillonite to nontronite has precipitated along with iron oxide under slightly reducing conditions. This deposition was apparently followed by amorphous iron oxide and silica precipitation, possibly under more oxic conditions. Oxygen isotope geothermometry indicates formation temperatures in the range of 31–57°C for the Loihi smectites. Trace element enrichments appear to be positively correlated with the isotopic formation temperature of the smectite, suggesting either increased trace element solubility within the higher-temperature vent fluids or increased smectite and iron oxide scavenging with increased precipitation rates. The trace element abundances further suggest the presence of polymetallic sulfides that either are directly associated with the smectites as amorphous phases or occur beneath these deposits in the volcanic pile of the seamount.  相似文献   

The origin of epigenetic graphite: evidence from isotopes   总被引：1，自引：0，他引：1  

Paul L Weis  Irving Friedman  Jim P Gleason 《Geochimica et cosmochimica acta》1981,45(12):2325-2332

Stable carbon isotope ratios measured in syngenetic graphite, epigenetic graphite, and graphitic marble suggests that syngenetic graphite forms only by the metamorphism of carbonaceous detritus. Metamorphism of calcareous rocks with carbonaceous detritus is accompanied by an exchange of carbon between the two, which may result in large changes in isotopic composition of the non-carbonate phase but does not affect the relative proportions of the two reactants in the rock. Epigenetic graphite forms only from carbonaceous material or preexisting graphite. The reactions involved are the water gas reaction (C + H₂O → CO + H₂) at 800–900°C, and the Boudouard reaction (2CO → C + CO₂), which probably takes place at temperatures about 50–100°C lower.  相似文献   

Shaping and Sharing Responsibility: Social Memory and Social Learning in the Australian Rural Bushfire Landscape     

Karen Reid  Ruth Beilin  Jim McLennan 《社会与自然资源》2018,31(4):442-456

Responding to increased frequency and severity of bushfires, Australian governments called for “shared responsibility” for bushfire preparation and mitigation. This requires engagement between all sectors of community—government agencies, businesses, not-for-profit, and residents. Fire management agencies remain concerned about whether all communities in fire-prone landscapes are equally equipped to participate in sharing responsibility. A related question is how experience of bushfire influences subsequent community fire management practices. This paper addresses social learning and social memory in a landscape that has experienced repeat bushfires between 2006 and 2013. It examines the relationships between memory, learning and practice among a farming community in western Victoria and government agencies with bushfire management responsibility. Findings suggest that social learning and social memory interact and new practices emerge as the participants embrace “shared responsibility.” However, ambiguities remain about “what” is being shared and what being “responsible” means at different points in preparation and response.  相似文献   

Spatiality,Maps, and Mathematics in Critical Human Geography: Toward a Repetition with Difference   总被引：2，自引：0，他引：2  

David O'Sullivan  Luke Bergmann  Jim E. Thatcher 《The Professional geographer》2018,70(1):129-139

Quantitative and cartographic methods are today often associated with absolute, Newtonian conceptions of space. We argue that some such methods have not always been and need not be so allied. Present geographic approaches to relational space have been largely advanced through radical political economic and feminist thought. Yet we identify quantitative and cartographic methods (taking as exemplars a range of thinkers, some of whom were most prominent in the 1960s and 1970s) that can contribute to these approaches to relational space. We suggest neglected methods to revisit, new alliances to be forged with critical human geography and cultural critique, and possible paths to enliven geographical imaginations.  相似文献   

Critical Data,Critical Technology in Theory and Practice     

Ryan Burns  Craig M. Dalton  Jim E. Thatcher 《The Professional geographer》2018,70(1):126-128

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