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31.
无锡光伏产业链中的全球-本地联系 总被引:4,自引:1,他引:4
以无锡市为例,通过实地调研当地光伏产业链中多晶硅生产、电池元件生产、组件制造、相关设备生产、光伏设备运维服务,以及光伏用户等不同环节,从全球生产网络的视角,考察全球-本地联系在当地光伏产业链形成演化和技术发展动态中的具体表现。结论指出:① 无锡光伏产业在短短10 a之内从“两头在外”的发展模式到形成全产业链竞争优势,体现了新兴技术的全球生产网络技术加速更新和产业快速转移的新特点;② 本地相关产业集群通过技术引进、消化和改进为新技术突破规模化瓶颈,获取市场竞争力打下基础,并由此对全球光伏技术发展的路径产生了关键影响;③ 产业进一步发展需要针对能源转型的长期目标,着重探索能源消费侧的技术转型路径。 相似文献
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王天民 《华北地质矿产杂志》1999,(2)
本文详细分析了黄金矿产地质勘查、矿山建设及金矿生产等阶段工作的特点及其相互关系,探索性地提出提前建矿,缩短探矿和建设周期的办矿方式,并就如何加快黄金发展步伐问题提出了几点思考。 相似文献
34.
1986-2006年国家自然科学基金大气科学领域面上项目基金资助及成果统计分析 总被引:4,自引:0,他引:4
利用国家自然科学基金委员会项目档案电子查询系统提供的历年项目申请书和结题报告定量化数据,对1986—2006年大气科学领域面上项目基金资助情况和成果进行了统计分析,并据此揭示了20年来面上项目基金资助强度的发展变化,分析了基金投入和成果产出之间的关系,以及科学基金项目在稳定我国大气科学人才队伍中的作用;也是大气科学领域自然科学基金面上项目20年资助状况的回顾和总结。 相似文献
35.
Peter Caithamer 《Mathematical Geosciences》2008,40(6):653-670
This paper analyzes world oil production data as a population/resource growth model. Both US and world oil production data
are analyzed in terms of the logistic growth curve. It is shown that the logistic growth curve, while a suitable model for
the American data, is not a suitable model for world oil production. A flexible family of curves which allows a wide range
growth rates is considered. Using a nonlinear regression, one can predict various peak dates and total recoverable resources
using different curves which all fit the data indistinguishably well. 相似文献
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Multi-biomarkers were characterized in surface soils with different vegetation during an annual cycle in Oregon, U.S.A., to study the composition and dynamics of soil organic matter (SOM). The major compound classes identified include saccharides, steroids, terpenoids, and homologous series of aliphatic lipids (n-alkanoic acids, n-alkanols, and n-alkanes). Saccharides, n-alkanoic acids, and sterols were the most dominant compound groups identified in Ryegrass field soils, whereas n-alkanoic acids, n-alkanols, and sterols were dominant in soils under conifer and deciduous vegetation. Plant species, instead of microbial organisms, was found to be the primary source influencing the concentration and distribution of the major biomarker tracers in the studied surface soils. Over an annual cycle, concentrations of higher plant lipids such as monoacyl glycerides, sterols, n-alkanoic acids and total wax were higher during summer (especially June–August). During fall into winter, the concentrations of all compounds decreased to steady state levels due to cessation of de novo synthesis and concomitant biodegradation and remineralization of detritus. Sucrose and glucose reached maximum concentrations during spring (especially March–May), which could be related with plant growth, especially rootlets in the soils. Mycose, the microbial/fungal metabolite, maximized during late summer, suggesting the concomitant increase of microbial/fungal activity with the increasing primary production. The composition and variation of biomarkers observed over an annual cycle improved our understanding of SOM dynamics in temperate soils, which could also be linked to regional and global carbon cycles. 相似文献
38.
Fully coupled global analysis of Floating Production Systems, including the vessel, the mooring system and the riser system is described. Design of the system can be a daunting task, involving more than 1000 load cases for global analysis. The primary driver for the mooring system and for the riser system is motion of the vessel. Vessel motions are driven by environmental forces, but are restrained by forces from the mooring and riser systems. Numerical models and procedures that provide accurate and efficient global modeling of the Floating Production System are presented. Both Time Domain and Frequency Domain procedures are included. The accuracy and efficiency of the procedures are illustrated in an example: a large semi with 16 mooring lines and 20 risers. The procedures provide the accuracy and efficiency for use of fully coupled analysis in design of Floating Production Systems from concept selection to final design, installation and operation. 相似文献
39.
Variations in the abundance of fisheries resources and ecosystem structure in the Japan/East Sea 总被引:1,自引:0,他引:1
Chang Ik Zhang Jae Bong Lee Young Il Seo Sang Cheol Yoon Suam Kim 《Progress in Oceanography》2004,61(2-4):245
Evidence supports the hypothesis that two climatic regime shifts in the North Pacific and the Japan/East Sea, have affected the dynamics of the marine ecosystem and fisheries resources from 1960 to 2000. Changes in both mixed layer depth (MLD) and primary production were detected in the Japan/East Sea after 1976. The 1976 regime shift appears to have caused the biomass replacement with changes in catch production of major exploited fisheries resources, including Pacific saury, Pacific sardine and filefish. Both fisheries yield and fish distribution are reflected in these decadal fluctuations. In the 1960s and 1990s, common squid dominated the catches whereas in the 1970s and 1980s, it was replaced by walleye pollock. In the post-1988 regime shift, the distribution of horse mackerel shifted westward and southward and its distributional overlap with common mackerel decreased. The habitat of Pacific sardine also shifted away from mackerel habitats during this period. To evaluate changes in the organization and structure of the ecosystem in the Japan/East Sea, a mass-balanced model, Ecopath, was employed. Based on two mass-balanced models, representing before (1970–75) and after (1978–84) the 1976 regime shift, the weighted mean trophic level of catch increased from 3.09 before to 3.28 after. Total biomass of species groups in the Japan/East Sea ecosystem increased by 15% and total catch production increased by 48% due to the 1976 regime shift. The largest changes occurred at mid-trophic levels, occupied by fishes and cephalopods. The dominant predatory species shifted from cephalopods to walleye pollock due to the 1976 regime shift. It is concluded that the climatic regime shifts caused changes in the structure of the ecosystem and the roles of major species, as well as, large variations in biomass and production of fisheries resources. 相似文献
40.