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51.
灾害中人员死亡的货币损失估算方法 总被引:7,自引:1,他引:7
本文重点探讨了自然灾害造成的人员死亡货币损失的估算方法,将个人未来收入的现值作为衡量损失大小的标准。在对实际灾情进行估算之后,结合中国的社会经济特点,指出了中国进行此项工作的必要性及其困难所在。 相似文献
52.
A first alternative for estimating the physical carrying capacities of natural areas for recreation 总被引:2,自引:0,他引:2
Utilizing an adaptation of the Universal Soil Loss Equation, this article discusses a method for approximating the physical carrying capacity of natural areas for outdoor recreation. Classification of forested woodland and field environments is based upon the conversion of ground cover coefficients to the percentage of ground cover required to maintain soil productivity over time. Four canopy types, three canopy densities, and two general types of ground cover are recognized in the equation as well as soil characteristics, topographical variations, and rainfall velocities and intensities. The method requires that the areal distribution of soils occurring within natural areas be mapped. Approximations will vary according to the intensity of the planning desired, and may range from a general classification of large land areas to highly site-specific evaluations. Data generated from over 40 years of cooperative research form the basis for classifying natural areas according to their relative physical capacities to accommodate outdoor recreation. 相似文献
53.
An uptake parameter u (L kg−1 d−1) and a loss rate parameter k (d−1) were estimated for the patterns of accumulation and loss of 133Cs by three fish species following an experimental 133Cs addition into a pond in South Carolina, USA. These u and k parameters were compared to similar estimates for fish from other experimental ponds and from lakes that received 137Cs deposition from Chernobyl. Estimates of u from ponds and lakes declined with increasing potassium concentrations in the water column. Although loss rates were greater in the experimental ponds, the times required to reach maximum Cs concentrations in fish were similar between ponds and lakes, because ponds and lakes had similar retentions of Cs in the water column. The maximum Cs concentrations in fish were largely determined by initial Cs concentrations in the water column. These maximum concentrations in fish and the times required to reach these maxima are potentially useful indicators for assessments of risks to humans from fish consumption. 相似文献
54.
安徽省环境系统经济损失值及其分布特征 总被引:5,自引:0,他引:5
提出了环境系统经济损失概念,并在这一概念框架中建立了符合安徽省实际情况的指标体系,测算了以货币值表达的1990年的安徽省及该省分地市、分行业,以及各损体类型的环境系统经济损失值,分析了各损失分布特征。结果表明,安徽省为人口增长和经济发展所付出的环境损失代价是巨大的。 相似文献
55.
56.
Risk Communication is increasingly important to the chemical and manufacturing industries in the wake of a wave of major incidents in recent years. However, risk communication strategies as they are currently implemented tend to place the chemical industry on the defensive. Renewed attempts should be made to place the life-saving benefits of the chemical industry back in the public eye and counter-balance the popular political view that the chemical industry is often responsible for loss of life. In truth, while the chemical industry suffers on the job fatalities like many industries, the frequency is much less than many common industries and the chemical industry provides benefits to society that ultimately save far more lives. 相似文献
57.
通过对容积为504.94m3的某型号压力容器出厂前水压试验的声发射检测,分析了其在升压和保压过程中的声发射信号特征及其来源。结合AE信号参数、波形及定位图分析,对该容器进行了声发射活性评价,确定需要后续复检的强活性区域。文章为压力容器的声发射检测和安全评价提供了理论指导和参考数据。 相似文献
58.
Benjamin J. Pitcher Heidi Ahonen Robert G. Harcourt Isabelle Charrier 《Die Naturwissenschaften》2009,96(8):901-909
In pinnipeds, maternal care strategies and colony density may influence a species’ individual recognition system. We examined
the onset of vocal recognition of mothers by Australian sea lion pups (Neophoca cinerea). At 2 months of age, pups responded significantly more to the calls of their own mothers than alien female calls demonstrating
a finely tuned recognition system. However, newborn pups did not respond differentially to the calls of their mother from
alien female calls suggesting that vocal recognition had not yet developed or is not yet expressed. These findings are in
stark contrast to other otariid species where pups learn their mother’s voice before their first separation. Variance in colony
density, pup movements, and natal site fidelity may have reduced selective pressures on call recognition in young sea lions,
or alternatively, another sensory system may be used for recognition in the early stage of life. 相似文献
59.
The distribution of air-filled structures in the craniofacial and neurocranial bones of the oviraptorid ZPAL MgD-I/95, discovered
at the Hermiin Tsav locality, Mongolia, is restored. Based on the complete obliteration of most of the cranial sutures, the
specimen is identified as an adult individual of Conchoraptor gracilis Barsbold 1986. Except for the orbitosphenoids and epipterygoids, the preserved bones of the neurocranium are hollow. Three
types of tympanic recess are present in Conchoraptor, a characteristic shared with troodontids, dromaeosaurids, and avian theropods. The contralateral middle ear cavities are
interconnected by the supraencephalic pathway that passes through the dorsal tympanic recesses, the posterodorsal prootic
sinuses and the parietal sinus. The spatial arrangements of the middle ear cavity and a derived neurocranial pneumatic system
in Conchoraptor indicate enhancements of acoustic perception in the lower-frequency registers and of auditory directionality. We further
speculate that this improvement of binaural hearing could be explained as an adaptation required for accurate detection of
prey and/or predators under conditions of low illumination. The other potentially pneumatic structures of the Conchoraptor cranium include (1) recessus-like irregularities on the dorsal surface of the nasal and frontal bones (a putative oviraptorid
synapomorphy; pos); (2) a subotic recess; (3) a sub-condylar recess; and (4) a posterior condylar recess (pos).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
60.