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201.
受人类活动的影响,海洋污染日益严重。我国海岸带、河口和海湾生态系统均受到了不同程度的破坏。海洋生态环境监测传感器的应用可实现实时海洋环境的监测和快速预警,对于预防海洋灾害、调节海洋经济发展与环境之间的矛盾有重要意义。文中归纳了海洋生态环境类传感器所应用的分析检测技术,总结了目前所研发的各类海洋生态环境传感器,预测了传感器的发展趋势,并对我国未来传感器的研究工作提出了建议。  相似文献   
202.
近年来,随着研究生教育规模的逐年提升,高年级本科教育目标也随之发生一定变化,遥感专业教学中,有必要加强对学生研究能力的培养。本文以矿区资源环境遥感课程为例,以课程综合实验为切入点,结合课程特点提出了半开放式、可拓展的实验架构,探索了面向本科生研究能力培养需求的实验方案设计及教学实践工作,引导学生由被动接受向主动思考转变;由知识吸收向研究实践转变。向学生展示本专业科学研究的基本方法,为学生顺利进入社会工作岗位或转入更高学习阶段打好基础。  相似文献   
203.
农作物长势遥感监测业务化应用与研究进展   总被引:1,自引:0,他引:1  
农作物长势监测可为田间管理提供及时的决策支持信息和早期估产提供依据。为了更好地研究作物生长过程中不同遥感监测作物长势方法的适用性,从多光谱遥感数据、高光谱遥感数据和微波遥感数据的应用及遥感监测指标与模型模拟方面综述了国内外农作物长势遥感监测研究及业务化应用的最新进展,指出了未来拟重点加强的研究任务,包括高时空分辨率和高光谱分辨率遥感数据的业务化技术、多遥感反演参数协同监测作物长势技术研发、基于遥感信息与作物过程模型的集合预报技术研究、全球尺度作物长势监测业务运行系统研发。  相似文献   
204.
Scientists’ ideas, beliefs, and discourses form the frames that shape their choices about which research to pursue, their approaches to collaboration and communicating results, and how they evaluate research outputs and outcomes. To achieve ocean sustainability, there are increasing calls for new levels of engagement and collaboration between scientists and policy-makers; scientists’ willingness to engage depends on their current and evolving frames. Here, I present results about how scientists involved in diverse fields of ocean research perceived their role as scientists working at or near the ocean science–policy interface and how this related to their perceptions regarding ocean research priorities. The survey of 2187 physical, ecological and social scientists from 94 countries showed that scientists held different perspectives about their appropriate level of engagement at the ocean science–policy interface and the relative primacy of science versus politics in formulating ocean policy. Six clusters of scientists varied in their frames; three clusters accounted for 94% of the sample. Of 67 research questions identified from 22 research prioritization and horizon scanning exercises, the top eight were shared among all three clusters, showing consistency in research priorities across scientists with different framings of their role at the science–policy interface. Five focused on the mechanisms and effects of global change on oceans, two focused on data collection and management for long-term ocean monitoring, and one focused on the links between biodiversity and ecological function at different scales. The results from this survey demonstrated that scientists’ framings of the role of ocean science at the science–policy interface can be quantified in surveys, that framing varies among scientists, and that research priorities vary according to the framings.  相似文献   
205.
The public's willingness to engage in mitigation actions has not received as much attention as the level of belief in Global Warming (GW), especially on the international stage. Research in Western nations indicates that people systematically misunderstand GW and the actions required for mitigation. Important factors that influence judgments about mitigation actions include personal experiences, beliefs, knowledge, values, and worldviews. We present results of an international survey (25 samples from 24 countries) measuring general intentions to act and willingness to engage in specific actions. Our analysis reveals that endorsement of specific actions is (a) lower than general endorsement of mitigation, (b) accompanied by higher intra-individual variance, and (c) more strongly related to personal experiences with GW. This pattern can be attributed to the compatibility between the proximal construal of specific actions and the nature of the personal experience. Lastly we provide recommendations on how these findings can be used to encourage mitigation action.  相似文献   
206.
The future exploration of Mars is likely to utilize resources that can be extracted in situ. An overview of the geology of Mars has been presented and several mechanisms that could result in the formation of ore deposits have been identified. These include deposits caused by hydrothermal fluids resulting from volcanic activity, large igneous province formation and impact craters. Surface enrichment of mineral sand deposits is also discussed. Where appropriate, terrestrial analogues of these mechanisms have been discussed and supporting evidence from observations of Mars undertaken to date presented. Types of deposits that are unlikely to be found on Mars are also listed.  相似文献   
207.
Anecdotal data sources may constitute an important component of the information available about an exploited species, as record keeping may not have occurred until after exploitation began. Here, we aimed to fill any gaps in the exploitative history of the sparid snapper (Pagrus auratus), using social and historical research methods. Social research consisted of interviews with recreational fishers, focusing on the most and largest snapper they had caught. In addition, the diary‐logs of two recreational fishers were analysed. Historical research consisted of investigation of old books, photos, archives and unpublished sources unconventional to fishery science. Interviews with fishers demonstrated no or weak trends in snapper abundance or size, and were likely impeded by a lack of ability to detect change in a fish stock that may still be considered abundant. The fishers’ perception of change, however, largely reflected recent experiences (last c. 10 years), when biomass is understood to have increased, and mostly did not consider experiences before the 1980s. Alternatively, diary‐logs of fisher catch rates produced a pattern that matched formal stock assessments of snapper biomass, suggesting declines in abundance up until the 1990s and an increase in biomass after that time. Historical research, although more qualitative, had the ability to investigate periods where formal records were not kept and described a fishery vastly different from the current one. Snapper were easily caught, in great abundance and in unusual locations. Localised depletion of snapper was first noticed in the early 20th century, despite spectacular catches of snapper occurring after that time. Snapper behaviour was also likely different, with visual sightings of snapper by onlookers a common occurrence. Although predictions from stock assessment models are consistent with that of the anecdotes listed here (i.e., high biomass in the past), these anecdotes are valuable as they explain lost biomass in a perspective meaningful to all. This perspective may be valuable for managers trying to consider the non‐financial value of a shared fishery but, if unrecognised, represents a shifting baseline.  相似文献   
208.
Interviewing landed elites in post-war Guatemala   总被引:1,自引:0,他引:1  
This essay explores the methodological challenges of conducting ethnographic research among economic and managerial elites in Guatemala’s landed sector during the country’s post-war transition. Guatemala’s 34-year civil war ended with peace accords in 1996. From the mid 1990s through 2001, I conducted interviews with leading representatives of the private sector in Guatemala, including the owners and top managers of the country’s sugar plantations. The Guatemalan sugar elite describes itself as the new face of the private sector in Central America, implementing “corporate social responsibility” programs linked to the World Bank and other international agencies. Questions of access and interview dynamics are often discussed in relation to qualitative research on “elites.” Yet, I found the interview process to be less complicated than I anticipated. Of greater concern were the problems of research dissemination and praxis. The experience discussed here raises questions about whether research on particular elite groups can be sustained over long periods of time.  相似文献   
209.
This essay reflects on issues of researcher positionality within participant observation and action research, and the specific methodological issues surrounding research on neoliberal governance strategies, using my experience at the US Environmental Protection Agency as case material. Although I was initially concerned about participating with the anti-progressive Bush Administration, I attempted to adopt the interests and subjectivity of an environmental bureaucrat. Doing so proved to be an extremely effective way of exploring the multi-vocality and cross-cutting interests constituting the state, which often appears from the outside to be a policy monolith. Participant research among elites in the neoliberal state is an effective way to observe such complexity. It became apparent that, because mainstream economics tends to adopt a totalizing epistemology, both its casual and dogmatic adherents usually do not conceive of a coherent external critique. This often means that researchers of any theoretical background can be quite frank concerning their purposes, background, and interests, even as participants.  相似文献   
210.
中国近年来先后在南海北部和祁连山南缘青海省天峻县永久冻土带中发现天然气水合物,这是一种新能源,它将对中国能源结构的调整和能源紧张的缓解起到非常重要的作用。但是,天然气水合物开采安全是个大问题,已经引起了国际上专家们的极大关注。俄罗斯南方国立技术大学地球物理、探矿工程和石油钻采教研室开发出来的天然气水合物开发安全检测技术和方法,可以准确确定出射孔部位的位置、检查射孔部位是否阻塞和如何解阻等关键技术,对天然气水合物开采安全提供了技术支撑,对此应该进行研究。  相似文献   
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