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121.
The decline in sea cucumber fisheries that serve the Asian dried seafood market has prompted an increase in global sea cucumber
aquaculture. The tropical sandfish (Holothuria scabra) has, in this context, been reared and produced with mixed success. In the Western Indian Ocean, villagers often participate
in the export fishery for sea cucumbers as a source of income. However, with a growing concern of depleted stocks introduction
of hatcheries to farm sandfish as a community livelihood and to replenish wild stocks is being promoted. This review identifies
and discusses a number of aspects that constitute constraints or implications with regard to development of sandfish farming
in the region. The conclusion is that for sandfish farming to live up to its expectations the possible impacts need to be
further studied, and that improved evaluation of ongoing projects is required. In the interim, a precautionary approach toward
new enterprise activities is suggested. 相似文献
122.
This paper contains a critical exploration of the social dimensions of the science–humanitarian relationship. Drawing on literature on the social role of science and on the social dimensions of humanitarian practice, it analyses a science–humanitarian partnership for disaster risk reduction (DRR) in Padang, Sumatra, Indonesia, an area threatened by tsunamigenic earthquakes. The paper draws on findings from case study research that was conducted between 2010 and 2011. The case study illustrates the social processes that enabled and hindered collaboration between the two spheres, including the informal partnership of local people and scientists that led to the co‐production of earthquake and tsunami DRR and limited organisational capacity and support in relation to knowledge exchange. The paper reflects on the implications of these findings for science–humanitarian partnering in general, and it assesses the value of using a social dimensions approach to understand scientific and humanitarian dialogue. 相似文献
123.
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125.
In this study we use a cross-sectional survey to evaluate the nutritional response to the 1998 Bangladesh Flood Disaster by 15 relief agencies using standards developed by the Sphere Project. The Sphere Project is a recent attempt by agencies around the world to establish universal minimum standards for the purpose of ensuring quality and accountability in disaster response. The main outcomes measured were resources allocated to disaster relief types of relief activities and percentage of agencies meeting selected Sphere food aid and nutrition indicators. Although the process of nutritional response was measured, specific nutritional and health outcomes were not assessed. This review found that self-reported disaster and nutritional resources varied widely between implementing agencies, ranging from US $58,947 to $15,908,712. The percentage of resources these agencies allocated to food aid and nutritional response also varied, ranging from approximately 6 to 99 per cent of total resources. Agencies met between 8 and 83 per cent of the specific Sphere indicators which were assessed Areas in which performance was poor included preliminary nutritional analysis; beneficiary participation and feedback; disaster preparedness during non-emergency times; monitoring of local markets and impact assessment. Agencies were generally successful in areas of core humanitarian response, such as targeting the vulnerable (83 per cent) and monitoring and evaluating the process of disaster response (75 per cent). The results here identify both strengths and gaps in the quality of humanitarian response in developing nations such as Bangladesh. However, they also raise the question of implementing a rights-based approach to disaster response in nations without a commitment to meeting positive human rights in non-disaster times. 相似文献
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127.
Max Renner 《Die Naturwissenschaften》1955,42(19):540-541
128.
Max Ziegler 《Die Naturwissenschaften》1959,46(22):629-629
129.
Tool wear in micro-milling poses a serious limitation to increased production rate, and atomized cutting fluids have been shown to be quite effective in increasing tool life in micro-milling operations. A new compact cutting fluid application system has been designed and developed based on ultrasonic atomization. In order to understand the effects of the system input parameters on system performance, two performance measures have been defined in terms of spray characteristics and experiments have been performed to evaluate the system according to the defined performance measures. Based on the experimental results, the system parameters can be adjusted to obtain the desired spray characteristics, and areas of improvement on the design have been identified. 相似文献
130.
Max Stocker 《Ecological modelling》1983,18(2):121-139
Optimal harvesting strategies for an ungulate population are estimated using stochastic dynamic programming. Data on the Llano Basin white-tailed deer (Odocoileus virginianus) population were used to construct a 2-variable population dynamics model. The model provided the basis for estimating optimal harvesting strategies as a feedback function of the current values of the state variables (prefawning older deer and juveniles). Optimal harvest strategies were insensitive to assumptions about the probability distributions of the stochastic variable (rainfall). The response of the population components to harvesting and the returns obtained from applying optimal strategies were explored through simulation. Mean annual harvest is about 15% of the population. Simplified harvesting strategies based on age-ratios as well as a simplified version based on optimal strategies—but assuming persisting equilibrium juvenile deer density—were compared to optimal strategies through examining values of information. Simplified harvesting strategies lead to a lower harvest over a 50-year simulation period. 相似文献