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21.
Polyc·lonal antibodies raised against LHC II isolated from SDS-solubilizedBryopsis corticulans thylakiod membranes by SDS-PAGE, were characterised by double immunodiffusion, Rocket immunoelectrophoresis and antigen-antibody crossed immunoelectro-phoresis assays showed the antibodies had strong cross-reaction with allB. corticulans LHC II components (even with those which were incubated in boiling water) and showed immunological cross-reactivity with LHC II polypeptides of spinach and the marine green algaCodium fragile. The results suggested that LHC II of different species had similar antigenic determinants and also conservation of amino acid sequences of the polypeptides during evolution, and that the antibodies could cross react with apoproteins of D2 proteins (which contain P680) fromB. corticulans, spinach andC. fragile, but not with apoproteins of P700 Chl-proteins. Our results indicated some similarities in primary structure between LHC II of different species, and between LHC II and D2 proteins of marine green algae and spinach. Our finding that D2 and P700 Chl-proteins are not immunologically related suggested that P700 Chl-proteins and D2 proteins pass through independent evolutionary pathways. Contribution No 1717 from the Institute of Oceanology, Academia Sinica, This subject was supported by the National Science Foundation of China.  相似文献   
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Using a subset of the SEG Advanced Modeling Program Phase I controlled‐source electromagnetic data, we apply our standard controlled‐source electromagnetic interpretation workflows to delineate a simulated hydrocarbon reservoir. Experience learned from characterizing such a complicated model offers us an opportunity to refine our workflows to achieve better interpretation quality. The exercise proceeded in a blind test style, where the interpreting geophysicists did not know the true resistivity model until the end of the project. Rather, the interpreters were provided a traditional controlled‐source electromagnetic data package, including electric field measurements, interpreted seismic horizons, and well log data. Based on petrophysical analysis, a background resistivity model was established first. Then, the interpreters started with feasibility studies to establish the recoverability of the prospect and carefully stepped through 1D, 2.5D, and 3D inversions with seismic and well log data integrated at each stage. A high‐resistivity zone is identified with 1D analysis and further characterized with 2.5D inversions. Its lateral distribution is confirmed with a 3D anisotropic inversion. The importance of integrating all available geophysical and petrophysical data to derive more accurate interpretation is demonstrated.  相似文献   
24.
Sediments produced by landslides are crucial in the sediment yield of a catchment, debris flow forecasting, and related hazard assessment. On a regional scale, however, it is difficult and time consuming to measure the volumes of such sediment. This paper uses a LiDAR‐derived digital terrain model (DTM) taken in 2005 and 2010 (at 2 m resolution) to accurately obtain landslide‐induced sediment volumes that resulted from a single catastrophic typhoon event in a heavily forested mountainous area of Taiwan. The landslides induced by Typhoon Morakot are mapped by comparison of 25 cm resolution aerial photographs taken before and after the typhoon in an 83.6 km2 study area. Each landslide volume is calculated by subtraction of the 2005 DTM from the 2010 DTM, and the scaling relationship between landslide area and its volume are further regressed. The relationship between volume and area are also determined for all the disturbed areas (VL = 0.452AL1.242) and for the crown areas of the landslides (VL = 2.510AL1.206). The uncertainty in estimated volume caused by use of the LiDAR DTMs is discussed, and the error in absolute volume estimation for landslides with an area >105 m2 is within 20%. The volume–area relationship obtained in this study is also validated in 11 small to medium‐sized catchments located outside the study area, and there is good agreement between the calculation from DTMs and the regression formula. By comparison of debris volumes estimated in this study with previous work, it is found that a wider volume variation exists that is directly proportional to the landslide area, especially under a higher scaling exponent. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
25.
This study presents an extended framework for the analysis of economic effects of natural disaster risk management. It also attempts to define and evaluate the optimal insurance arrangements. A model, the economic utility constrained-maximization model, is proposed. The purpose of this study is to establish a strategy for determining an insurance and risk control plan in which consideration is given to balancing the economic effects (e.g., decrease in costs due to damage) by disaster mitigation. Furthermore, these values are compared with risk control actions for purposes of prioritization, to provide data to help evaluate the benefit of each risk control action. Disaster insurance policy premiums in contrast are based on actuarial data taken from situations in which risk control measures are not employed. This can make such contracts unfair to responsible enterprise managers who must take risk control measures. This represents an unfair aspect of insurance policies. Enterprise managers should be able to determine the optimum arrangement between natural disaster risk control and insurance given their budget limitations. The optimal strategies aim at the best applicability and balance between risk control and insurance capability for the enterprise manager. Risk control measures can generate several risk control options for enterprise managers. Premium discounts by insurers are given in this model.  相似文献   
26.
Hazard management and risk design by optimal statistical analysis   总被引:2,自引:2,他引:0  
Elicitation methods are used in decision making with respect to risk hazards to allow a researcher to infer the subjective utilities of outcomes from the observed preferences of an individual. A questionnaire method is presented, in this study, which takes into account the inevitable distortion of preferences by random errors and minimizes the effect of such errors. Under mild assumptions, the method for eliciting the utilities of many outcomes is a three-stage procedure. First, the questionnaire is utilized to elicit responses from which a subjective score is defined. Second, individual risk factors are discussed. Finally, the regression model presents individual risk preferences given the overall organizational risk culture, risk management policy, risk identification, and risk analysis. This paper addresses how company managers face risk and their tolerance of risk with respect to risk management.  相似文献   
27.
Natural disaster risk, a long-time concern in the insurance industry, is increasingly recognized as a present danger in the business strategies of risk control and enterprise management agencies. Floods and earthquakes can cause massive loss of life and infrastructure, resulting in business interruption and heavy casualties. Many of the short-term developmental strategies employed throughout the world have only served to exacerbate the impact of natural disasters. Therefore, this study presents a review of formal methods that are commonly used in risk and uncertainty analysis in planning and concludes with a critical assessment of the advantages and disadvantages of the different priority setting methods. Our focus is a preliminary proposal for developing an efficient probabilistic approach to facilitate design optimization that involves probabilistic constraints.  相似文献   
28.
Typhoon Morakot hit Taiwan in 2009, severely damaging the Alishan National Forest Recreation Area, a famous tourist resort in Taiwan. The only highway to this area was under repair for 10 months after the typhoon. Consequently, Alishan’s tourism industry suffered losses estimated at NT$1 billion. This work investigates the impacts of natural hazards on Taiwan’s tourism industry. First, government, university, and industry experts were invited to a focus-group interview to update criteria for tourism development in Taiwan. Next, the Analytic Hierarchy Process (AHP) was applied to rank the proposed criteria. Last, two tourist attractions, one urban and one rural, are discussed in detail. This work proposes three novel dimensions for Taiwan’s tourism development—destination attraction, destination arrangement, and contingency planning for natural hazards—which comprise nine criteria. Analytical results will provide Taiwan’s tourism industry with references for future policy-making and sustainable development.  相似文献   
29.
The responses of coastal upwelling to different magnitudes of wind stress over a narrow and a wide shelf are studied using a 3-D primitive equation numerical model. The results show that the position of the upwelling front depends on both the strength and the duration of the wind forcing. The comparison between different shelf widths shows that wide shelf will limit the cold water intrusion, so that the corresponding decrease in sea surface temperature is less compared to narrow shelves. Besides, the difference between hydrostatic and nonhydrostatic model results shows that nonhydrostatic effects will enhance the growth of surface meandering, and can be more pronounced near steep fronts. Although difference does exist, our results show that the nonhydrostatic effects are very small at least in this idealized study case.  相似文献   
30.
Impulsive force of debris flow on a curved dam   总被引:8,自引:0,他引:8  
Although Sabo dams are an efficient method for river and basin management, traditional Sabo dams have a great impact on ecology and landscape. Moreover, such dams are hit and often damaged by great impulsive force when they block the debris flow. Therefore, alternative shapes for Sabo dam deserve thorough investigation. In this investigation, a curved dam was designed by changing the upstream-dam-surface geometric shape to reduce the impulsive force of the debris flow, with enhanced stability and reduced concrete mass being the anticipated outcomes. In this study, the flume and laboratory facilities simulated the impulsive force of the debris flow to the Sabo dams. Three geometric forms, including vertical, slanted and curved Sabo dams, were used to determine the impulsive force. Impulsive force theories of the debris flow were derived from the momentum equation and the Bernoulli equation. In these, the impulsive force was balanced by the friction force of the Sabo dam and the opposite force of the load cell behind the dam as it was hit by the debris flow. Positive correlations were found when comparing the experimental data with the theoretical results. These findings suggest that our impulsive force theory has predictive validity with regard to the experimental data. The results from both theory and experimental data clearly show that curved darns were sustained less force than the other darns under the same debris flow. This comparison demonstrates the importance of curved geometry for a well-designed Sabo dam.  相似文献   
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