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191.
192.
This paper addresses the problem of inter-organizational coordination in response to extreme events. Extreme events require coordinated action among multiple actors across many jurisdictions under conditions of urgent stress, heavy demand and tight time constraints. The problem is socio-technical in that the capacity for inter-organizational coordination depends upon the technical structure and performance of the information systems that support decision making among the participating organizations. Interactions among human managers, computers and organizations under suddenly altered conditions of operation are complex and not well understood. Yet, coordinating response operations to extreme events is an extraordinarily complex task for public and nonprofit managers. This paper will analyze the interactions among public, private and nonprofit organizations that evolved in response to the 11 September 2001 attacks, examining the relationships among organizations in terms of timely access to information and types of supporting infrastructure. The performance of the inter-organizational system is examined in the context of the events of 11 September 2001 from the theoretical perspective of complex adaptive systems. A model of auto-adaptation is proposed for implementation to improve inter- organizational performance in extreme events. This model is based on the concept of individual, organizational and collective learning in environments exposed to recurring risk, guided by a shared goal. Such a model requires public investment in the development of an information infrastructure that can support the intense demand for communication, information search, exchange and feedback that characterizes an auto-adaptive system.  相似文献   
193.
An almost 6,000 years old slide in marine clay at Fossmoen, Northern Norway is studied to: characterize the scar, the slide deposits and the slide event; evaluate the role that stratigraphic variations played for failure; and view the slide event within long-term landscape development. A geological model for the area is based on drilling, outcrops and ground-penetrating radar with emphasis on the stratigraphic variations of fjord deposits. The slide’s age implies that the deposits were sensitive already shortly after emergence above sea level, and layers are still sensitive. River incision was probably responsible for the initial slide, whereas stratigraphy and groundwater movement controlled the location and shape of the scar. Laminated, inclined and discontinuous bedding are suggested as playing different roles for ground-water flow and pore pressures, adding to existing models on the development of soft and sensitive layers prone to sliding.  相似文献   
194.
High resolution profiles of permitted and forbidden lines in symbiotic stars are described, with particular reference to the broad wings. An interpretation of the data in terms of an optically thin accretion disc around a hot subdwarf is presented.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.  相似文献   
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196.
Quantum conception of virtual energy exchange between masses leads to the Newton's law. A guide wave similar to the De Broglie's one (1923) is able to account quantitatively for the Titius-Bode law occurring in the planetary system as well as the satellite systems.  相似文献   
197.
Most of the dissolved organic materials (DOM) in coastal Maine, Gulf of Maine, and North Atlantic seawaters had molecular weights (MW), determined by ultrafiltration, less than 1000. Only 34% of the DOM had MW greater than 1000, only 6% had MW greater than 30 000, and only 1% was of MW greater than 100 000. The majority of ultrafilter-derived MW data are consistent with patterns shown here; earlier reports of high-MW DOM in seawater were apparently exaggerated due to procedural and ultrafilter artifacts. It is also shown that most ultrafiltration data do not clearly indicate loss of high-MW DOM during estuarine mixing, and that apparent removal could result from decreased retention as ionic strength increases.  相似文献   
198.
Several monomeric organic compounds, including amino acids, sugars, and fatty acids, were found to bind abiologically to dissolved macromolecular materials in particle-free seawater at natural substrate concentrations. The binding primarily occurred in ocean surface waters, at rates slower than in situ biological utilization rates of most of the compounds. Seasonal patterns of binding in Gulf of Maine waters may have been related to seasonal variations in macroalgal exudation of polyphenolic materials. Enhanced reactivity of relatively hydrophobic monomers implicated hydrophobic effects as potentially important in marine organic condensations. The resultant condensates showed high particle reactivity, consistent with low concentrations of dissolved condensed materials in seawater.  相似文献   
199.
Aeolian sand transport during winter and the snow-free season was assessed quantitatively by direct year-round field measurements along transects on the lee side of parabolic dunes in subarctic Québec. In 1987–1988, niveo-aeolian deposition was more important than aeolian sedimentation in three of the four study sites, and contributed > 75% of the total annual accumulation in exposed sites and < 25% in protected forest sites. The maximum depth of interstratified snow and sand deposits (3.5 m) was recorded in March. Semi-permanent snow lenses may persist longer than 2 years in the aeolian sediments. After dissipation of snow, 22 cm of sand (as a maximum) accumulated on the slipface of the most active dunes, whereas only minor sand accumulation occurred in distant areas from active sand erosion. Wind-driven sand was dispersed over 7.4 km2 in the Whapmagoostui-Kuujjuarapik area. The acumulation of snow and sand during the snow season, together with spring thaw and collapse of the niveo-aeolian deposit, caused different types of injuries to trees, especially in 1985 and 1987 when a maximum of torn branches was recorded over the last 10 year period.  相似文献   
200.
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