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101.
Confirmed observations of meteoroids from the Leonid stream impacting the Moon in 1999 and 2001 have opened up new opportunities in observational and theoretical astronomy. These opportunities could help bridge the gap between the ground-based (atmospheric) sampling of the smallest meteoroids and the larger objects observable with ground-based telescopes. The Moon provides a laboratory for the study of hypervelocity impacts, with collision velocities not yet possible in ground-based laboratories. Development of automatic detection software removes the time-intensive activity of laboriously reviewing data for impact event signatures, freeing the observer to engage in other activities. The dynamics of professional-amateur astronomer collaboration have the promise of advancing the study of lunar meteoritic phenomenon considerably. These three factors will assist greatly in the development of a systematic, comprehensive program for monitoring the Moon for meteoroid impacts and determining the physical nature of these impacts.  相似文献   
102.
The conceptual framework of local buzz and global pipelines has received much attention. It suggests that regional collaboration (local buzz) in particular will induce value creation if combined with international collaboration (global pipelines). Here, we analyze national data from Norway and find that both regional and international collaboration can foster product innovation. However, for medium-sized enterprises, we only found a substitution effect from combining regional and international collaboration. For small enterprises, there was even a subtractive effect. For large enterprises, we found an additive effect, and for very large enterprises, there was a multiplicative effect. It thus appears that large enterprises have an increased absorptive capacity in handling both regional and international collaboration. We conclude that the local buzz and global pipelines proposition is rejected for small and medium-sized enterprises, and gains partial to full support for large and very large enterprises.  相似文献   
103.
以北极研究为中心,基于CNKI和Web of Sciences Core Collection数据库2000—2017数据,采用CiteSpace,系统展示了中国和国际(含中国)在北极科研领域的发展趋势、前沿、热点和机构合作特征。研究表明,国内的北极研究经历了由气候海冰—航运—北极治理的研究过程,发文量以北极航运为主导。国际针对北极的研究经历了三个逐步加速阶段:1990、2000和2005,北极八国和德、英、法是北极研究的主力军。北极科技合作仍主要以国家内部合作为主,但科研机构合作频率高度爆发且出现一批以“Helmholtz Centrefor Polar and Marine Research(德国)、The Arctic University of Norway(挪威)、Aarhus University(丹麦)和KoreaPolar Research Institute(韩国)”为代表的北极研究合作爆发单位;北极研究领域多样,呈现出以“arcticocean”、“climate”、“arctic temperature”、“variability”、“sea ice”、“model”等为重点的关键词,表明近年国际北极研究主要热点在气候变化、海冰、洋流等领域,这些领域相互交叉。通过对国内外北极通航经济性的系统综述分析得出:国内外学者均认为与北极海冰有关因素是制约北极通航的关键;国内学者对北极通航的经济效益较为乐观,而国外学者则较为辨证且谨慎。这与研究所考虑的角度有关,国内学者较多考虑北极通航的技术管理、人力资源、能耗、时间和政治等因素,而国外学者在这些因素的基础上,还侧重于贸易需求、通航意愿性和通航对气候的影响等因素。  相似文献   
104.
浦东新区中小高新技术企业创新合作网络构成特征研究   总被引:1,自引:2,他引:1  
文章以上海市浦东新区为例,研究了中小高新技术企业创新网络构成及特征。由于企业集聚的原因不同,以及在浦东集聚的时间较短,企业间、企业与高校、科研机构及其他组织机构间的来往还不够频繁,创新合作网络的信任机制还没有充分建立起来,企业的创新合作网络建设还处于一个初级阶段。浦东外向型经济使得其中小企业创新合作网络具有外向度高的特点,企业与国外供应商、海外大学、科研机构等进行创新合作。加工区、保税区和高科技园区的工业开发模式对中小企业创新网络构成具有影响,使其网络构成表现出一定的差异性。  相似文献   
105.
Collaboration Across Borders: Moving Beyond Positionality   总被引:2,自引:0,他引:2  
Discussions about collaborative spaces in postcolonial feminist and geographical analyses have often hinged on questions of positionality, reflexivity and identity, largely in relation to the politics of representation. Such approaches have often led to an impasse, especially in fieldwork-based feminist research, where reflexivity has mainly focused on examining the identities of the individual researcher rather than on the ways in which those identities intersect with institutional, geopolitical and material aspects of their positionality. This kind of identity-based reflexivity does not distinguish systematically between the ethical, ontological and epistemological aspects of fieldwork dilemmas; it also fails to adequately address how our ability to align our theoretical priorities with the concerns of communities whose struggles we want to advance is connected to the opportunities, constraints and values embedded in our academic institutions. This article takes this discussion forward by arguing for a postcolonial and transnational feminist praxis that focuses explicitly and deliberately on (a) conceptualising and implementing collaborative efforts that insist on crossing multiple and difficult borders; (b) the sites, strategies and skills deployed to produce such collaborations; and (c) the specific processes through which such collaborations can find their form, content and meaning. To ground this discussion, I draw upon two collaborative initiatives that I have begun recently in the state of Uttar Pradesh, north India.  相似文献   
106.
The Institute of Geophysical and Geochemical Exploration in China recently prepared ten biogeochemical certified reference samples GSB1‐10 (CRMs). The samples are primary agricultural products such as rice, wheat, corn, soybean, cabbage, spinach, tea, powder, chicken and apple. Lyophilisation technology and a high‐alumina ball mill were used to process the samples. Fourteen laboratories and hundreds analysts in China participated in the certification analysis. Over ten reliable analytical methods, predominately ICP‐MS, ICP‐AES and INAA, were used for analysing the samples for fifty‐nine elements. A total of 22477 determinations led to 5136 average data sets. Certified values of fifty‐four elements were assigned.  相似文献   
107.
尽管国际气候谈判充满矛盾,但本质上它是一种认真而责任重大的全球性努力,气候谈判的目标在于建立合理的国际气候制度。应对气候变化的实质是引导全球以低碳、绿色、循环发展为路径,实现全人类的可持续发展。气候谈判应该是一个促进各方建设性达成全球气候制度安排的过程,为此建议抓住以下三个重点:先发达国家率先做出积极的绝对量减排承诺;发展中国家也根据自身的能力和发展阶段做出自己应有的贡献;发达国家应在资金和技术上做点实事。先在以上三方面取得实质性突破,再通过公约原则下的“审评”和“调整”机制,逐步补充和完善。这是一种体现“自下而上”和“自上而下”相结合的路径。国际气候谈判的最终出路在于合作共赢。中国积极而务实地参与国际气候谈判的深刻原因,首先源于自身科学发展和可持续发展的内在需求,同时也是一个负责任的发展中大国对国际责任的担当。  相似文献   
108.
苏雅  杨明辉  苏永华  梁斌 《岩土力学》2013,34(9):2661-2666
首先利用遗传算法(GA)的全局优化能力,解决了Kriging插值预测算法中相关参数的精确求解问题。针对衬砌结构力学状态表征量与基本参数是高度非线性关系而无法明晰表达的难题,建立了基于Kriging插值预测法的状态表征量等代显式通用模型。以抗拉强度控制参量为例,提出了采用拉丁抽样等代显式通用模型的具体隧道工程衬砌结构力学状态方程构造程序。基于以状态方程为约束条件建立的可靠度指标计算模式,构建起Kriging与GA协同优化的隧道衬砌稳定可靠度求解方法。实例应用对比表明,该方法与精确解的相对误差为4.8%,计算工作量仅为其2.5%。与目前已有的同类方法相比,具有明显的优越性。  相似文献   
109.
地震应急指挥协同技术平台设计研究   总被引:7,自引:7,他引:0  
地震应急指挥协同服务能力是国家地震社会服务能力建设的核心内容,我国的地震应急指挥协同服务能力在研究和建设方面尚处于起步阶段,在未来一段时间将开展地震应急指挥协同技术平台的建设。因此,地震应急指挥协同技术平台的关键构成、设计和实现方式还有许多方面有待进一步研究和探讨。本文根据国家地震社会服务工程的初步设计,对地震应急指挥协同技术平台几个方面的内容进行了初步探讨,在此基础上讨论了其未来进一步发展应进行的工作。  相似文献   
110.
This paper studies knowledge production in complex, collaborative research projects that brought together academics from different disciplines, research users and agricultural businesses. It takes a comparative approach, studying the interactions within interdisciplinary research teams from ten case studies, considering the process of collaboration from initial idea through to publication. The research developed a typology of participants in these projects, and identified the motivations and challenges of each. Our results analyse the process of research teams coming together and the relationships that are built up during the research. A particular challenge identified was the building of cooperation and trust. This issue is explored alongside issues of communication, methodology, data analysis and the process of drawing and publicising conclusions.  相似文献   
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