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111.
If unauthorized resource use is prevented, managing marine resources by allocating property rights may match economic and environmental conservation incentives. However, because of the developing exploitation of marine resources and accompanying pollution, species' living conditions in Europe's waters are changing more quickly than before. By considering the roles of fisheries productivity, intellectual property rights, intellectual capital rights, market size, governance, and economic growth from 1990 to 2022, this paper aims to investigate the dynamic effect of property rights factors on the sustainability of the fisheries industry in 27 European countries. At higher quantiles, the findings showed a significant positive association between governance and fisheries sustainability adopting a new method, the MMQR with fixed effects, the Method of Moments Quantile Regression. In addition, in EU27 nations, the impact of intellectual property rights was favorable and statistically significant from the first to ninth quantiles. The findings show that the EU14 developed nations have more excellent governance and intellectual capital rights than the EU13 developing countries, significantly benefiting fisheries sustainability. In the same way that market size and economic growth condense fisheries sustainability in EU14 developed and EU13 developing countries, it has been discovered that intellectual property rights do the same across all quantiles, supporting the growth hypothesis for fisheries-producing countries. The findings specifically show that the beneficial solid impact of intellectual property rights, market size, and economic development on the sustainability of fisheries is more significant in EU13 developing nations than in EU14 developed countries. These results provide policymakers with helpful information for promoting property rights aspects in EU14 and EU13 nations via effective green technologies in the fisheries sector to meet sustainable development objectives.  相似文献   
112.
为了进一步保证封隔器安全坐封,提高封隔器胶筒的力学性能,基于现有成熟技术,设计了一种新型防突装置,分析了不同防突装置材料和结构参数对封隔器胶筒肩部突出、接触应力、Von Mises应力的影响。结果表明:新型封隔器肩部突出距离相比常规封隔器降低了63.35%,使胶筒不易被破坏,延长了胶筒的寿命;对防突装置材料和结构参数进行优选,选择材料为铝合金,距胶筒端面距离H=2.5mm,厚度B=0.5mm的新型防突装置;新型防突装置的设计与应用为封隔器坐封提供了安全保障。  相似文献   
113.
There are complex connections between Australia’s native plants and first peoples, the Aboriginal and Torres Strait Islander peoples. The maintenance of these connections is central to Aboriginal and Torres Strait Islander culture and well-being and the tangible realisation of Australian policy commitments. Diverse cultural connections combine with other motivations to underpin an array of Aboriginal and Torres Strait Islander interests in the commercial development of traditional plant foods (‘bush foods’). Despite nation-wide policy support for these interests, there is no national legal framework to support them. This fortifies the popular call for a new (sui generis) law that transforms the interests of Aboriginal and Torres Strait Islander peoples into enforceable legal rights. It is unclear the extent to which a single sui generis law might help Aboriginal and Torres Strait Islander peoples realise their diverse interests in the development of gourmet bush food products and new bush food varieties. It is also unlikely that Australia will implement such a law in the near future. This paper offers a preliminary study of the capacity of current legal structures to support some key Aboriginal and Torres Strait Islander interests that might arise in these two development contexts. The study can inform the future development of practical legal strategies to support the diverse interests of Aboriginal and Torres Strait Islander peoples in the bush food industry.  相似文献   
114.
南京2013年冬季三级分粒径雾水化学特征   总被引:2,自引:0,他引:2  
为研究南京冬季不同粒径雾滴的化学成分的特征,利用three-stage CASCC主动式分档雾水采集器,于2013年12月7日~12月9日南京郊区发生浓雾期间,分时段采集三级分档雾水样本,分档粒径为4~16μm(三级)、16~22μm(二级)、>22μm(一级),共计23个分档雾水样本;用瑞士万通850professional IC型色谱仪器测定水溶性阴、阳离子浓度,分析探讨了三级分粒径雾水中阴、阳离子组分的分布特征,不同粒径雾滴中阴、阳离子浓度的相关性,雾水离子浓度与污染气体以及微物理之间的关系.结果表明,南京雾水的pH值多呈酸性,雾水中的各离子成分分布都与雾滴的大小存在着尺度依赖性关系,小雾滴与大雾滴相比,小雾滴中主要离子成分浓度(NH4+,NO3-,SO42-)高、pH值小且电导率(EC)值高.同时南京雾水中的各离子浓度呈现出夜间高白天低.统计分析显示,南京雾过程中雾水组分的变化,主要源于污染源的贡献差异.结合雾滴谱和污染气体资料分析得出,雾水化学组成的变化与微物理特征以及空气中污染气体有关.  相似文献   
115.
116.
依据文家滑坡的地质勘查成果,对其滑体、滑带、滑床等岩土体物理力学性质,特别对C、φ值的取定进行了分析评价,力求为滑坡稳定性分析及后期防治工程设计提供科学合理的依据.  相似文献   
117.
自然资源由于其较强的公共性和外部性而使其因代际问题所导致的私有市场失灵比一般的产品严重,原因是自然资源代际利用中当代人都倾向于最大限度使用资源,从而引发自然资源“公地悲剧”问题比一般产品严重。再生自然资源虽然在代际利用中的利益冲突比非再生自然资源低,但代际问题所带来的市场失灵依然存在。因此,再生自然资源的代际可持续利用需要政府依据其经济特性进行一定的规制,制订出合理的使用制度。以渔业资源为例,在沙发尔(Schaefer)模型的基础上,利用成本——效益的经济学分析法,分析了再生自然资源代际可持续利用中的成本与收益,提出再生自然资源代际可持续使用的制度安排和优化措施,包括边际成本动态规制、明确界分所有权、实施可交易配额和公共补偿性规制。  相似文献   
118.
Mechanical waste-processing methods, which combine crushing and separation processes for the recovery of valuable materials, have been widely applied in waste printed wiring board (PWB) treatment. However, both the high impact toughness and the tensile and flexural strengths of whole PWB with a laminated structure result in great energy consumption and severe abrasion of the cutters during multi-level crushing. In addition, the high temperatures occurring in continual crushing probably cause the decomposition of the polymer matrix. A thermal-crack method using residual steam as the heating medium has been developed to pre-treat waste PWBs. This treatment reduces the mechanical strength in order to improve the recovery rate of valuable materials in subsequent mechanical recycling. The changes of the PWBs’ macro-mechanical properties were studied to evaluate thermal expansion impacts associated with changes in temperature, and the dynamic dislocation micro-structures were observed to identify the fracture mechanism. The results showed that thermal cracking with steam at the temperature of 500 K can effectively attenuate the mechanical properties of waste PWBs, by reducing the impact, tensile and flexural strengths respectively, by 59.2%, 49.3% and 51.4%, compared to untreated PWB. Thermal expansion can also facilitate the separation of copper from glass fiber by reducing peel resistance by 95.4% at 500 K. It was revealed that the flexural fracture was a transverse cracking caused by concentrated stress when the heating temperature was less than 500 K, and shifted to a vertical cracking after exceeding 500 K.  相似文献   
119.
SUMMARY

In recent years, indigenous tenure over forest lands has emerged as a means to conserve forests while recognizing indigenous rights. There is concern, however, that indigenous reserves may not be an appropriate policy tool for sustained forest conservation. Our research examined how recognition of indigenous common-property rights has controlled agricultural expansion and conserved forests in Bosawas Biosphere Reserve, Nicaragua. We used satellite imagery with empirical data gathered in the field on land-use institutions, population pressures, and land-use practices to compare whether indigenous communities under territorial management or public management are better able to (1) control the ‘fast threat’ of frontier expansion and (2) address the long-term ecological threats posed by indigenous land-use practices and institutional changes in the region. Our findings are that indigenous residents who share common-property rights over their territories are better able to control agricultural expansion than are indigenous residents living on public lands. With respect to the long-term threats to the region, a series of simulations of possible land-use pressures demonstrate that the enforcement of territorial boundaries and further development of indigenous forest management rules will prove crucial in determining land-use capacity and deforestation over the next 50 years.  相似文献   
120.
This article presents a system dynamics (SD) method to examine the problem of forest degradation. The model developed takes a system-oriented view of forest management, embracing both social and biophysical factors affecting deforestation. Social factors examined are socio-economic variables or elements that influence behaviour and decision-making choices at the household level. Biophysical factors are four sub-components that are considered major land uses namely, the paddy field component, rattan plantations, coffee plantations and forest stands. The model was applied in a case study located in Pasir District of East Kalimantan, Indonesia. The site covers an area that includes a protected forest and a privately allocated timber license concession. Three village communities are examined in the case study. The SD model developed was applied to the case study focusing on three management policies or scenarios, which are based on access rights to the forest resources within the study area. Specifically, the property arrangements examined in each scenario are: Policy 1 – status quo (i.e. continue present property rights arrangements); Policy 2 – local communities manage the forest exclusively; and Policy 3 – collaborative management involving both local communities and a private company. Results from the model show that the third policy is the most viable option, and also lead to a win–win solution.  相似文献   
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