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91.
目的:基于专利信息对我国3D生物打印技术的发展态势进行分析。方法:本文基于incopat和TDA两大专利分析平台对中国3D生物打印的专利发展态势从专利统计分析与专利计量分析两个维度进行了跨库组合分析,总结了我国3D生物打印技术的专利前沿动态特征。结果:研究发现,中国3D生物打印技术从2013年起进入专利激增态势,中国作为潜在技术市场的国际竞争日趋激烈,本文还从专利申请人、技术领域分布、专利文本关键词聚类、专利价值、专利合作等方面进行了深度挖掘分析。结论:最后,结合对中国3D生物打印专利申请人的专利产业化案例深度分析与专利特征总结,为中国3D生物打印技术发展与产业化提供参考建议。 相似文献
92.
菊方翅网蝽Corythucha marmorata(Uhler,1878)是我国新近发现的外来入侵害虫,研究明确菊方翅网蝽在我国的潜在分布范围对其监测预警及科学防控具有重要意义。本研究根据菊方翅网蝽的地理分布数据及相关环境变量,运用Maxent生态位模型与ArcGIS预测了菊方翅网蝽在中国的潜在地理分布范围。预测结果表明:菊方翅网蝽在我国的适生区主要分布于100°~125°E,20°~40°N的亚热带、暖温带区域,其中高适生区主要集中在长江中下游地区,包括浙江、江苏、湖南、上海大部分地区、安徽南部、湖北南部、江西西部及南部、贵州东部、福建东部、广西北部、山东中部、河南南部以及重庆、台湾局部;此外,极端气温、平均气温、最干月份降雨量对菊方翅网蝽的潜在分布影响较大。菊方翅网蝽已在我国成功入侵并迅速蔓延成灾,应在疫区边缘地带加强监测,并采取措施防止其进一步扩散。 相似文献
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Brandon Kuczenski 《Journal of Industrial Ecology》2019,23(3):574-586
Many of the challenges facing knowledge synthesis from life cycle assessment (LCA) studies stem from the inability of study authors and readers to formally agree on the structure and content of the product system models used to perform LCA computations. This article presents a framework for formally disclosing the foreground of an LCA study in a way that permits the computations to be inspected, verified, and reproduced by a reader, provided that the reader has access to the same life cycle inventory and impact characterization resources as the author. The framework can also be used to partition a study into public and private portions, allowing both portions to be critically reviewed but omitting the private information from the disclosure. A disclosure is made up of six components, including three lists of entities in the model and three sparse matrices describing their interconnections. The entity lists make reference to previously‐published resources, including background inventory databases and characterized elementary flows, and the disclosure framework requires both author and reader to agree on the meaning of each of these references. The framework contributes to ongoing efforts within and beyond industrial ecology to improve the reproducibility and verifiability of scholarly works, and if implemented, plots a course toward distributed, platform‐independent computation and validation of LCA results. 相似文献
96.
To analyze and promote resource efficiency in urban areas, it is important to characterize urban metabolism and particularly, material flows. Material flow analysis (MFA) offers a means to capture the dynamism of cities and their activities. Urban‐scale MFAs have been conducted in many cities, usually employing variants of the Eurostat methodology. However, current methodologies generally reduce the study area into a “black box,” masking details of the complex processes within the city's metabolism. Therefore, besides the aggregated stocks and flows of materials, the movement of materials—often embedded in goods or commodities—should also be highlighted. Understanding the movement and dispersion of goods and commodities can allow for more detailed analysis of material flows. We highlight the potential benefits of using high‐resolution urban commodity flows in the context of understanding material resource use and opportunities for conservation. Through the use of geographic information systems and visualizations, we analyze two spatially explicit datasets: (1) commodity flow data in the United States, and (2) Global Positioning System‐based commercial vehicle (truck) driver activity data in Singapore. In the age of “big data,” we bring advancements in freight data collection to the field of urban metabolism, uncovering the secondary sourcing of materials that would otherwise have been masked in typical MFA studies. This brings us closer to a consumption‐based, finer‐resolution approach to MFA, which more effectively captures human activities and its impact on urban environments. 相似文献
97.
以肃南裕固族自治县鹿场冬季牧场为研究对象,采用偏离系数及t检验方法结合Ripley''s K函数及蒙特卡罗随机模拟对紫花针茅种群与醉马草种群进行格局分析,进一步采用计盒维数与信息维数对紫花针茅种群与醉马草种群进行分形分析,揭示在放牧系统中优势植物的种群变化。格局分析结果表明:牧场植物的种群格局出现5种变化规律。紫花针茅种群的偏离系数在放牧率3.64 AUM/hm2时#,出现最小值。醉马草种群的偏离系数在放牧率4.16AUM/hm2时,出现最大值。在0-1 m的研究尺度内,紫花针茅种群与醉马草种群的Ripley''s K函数结果均在蒙特卡洛随机模拟区间内,呈随机分布格局。分形分析结果表明:伴随放牧率增大,紫花针茅种群的计盒维数区间为[1.596,1.962],醉马草种群的计盒维数区间为[1.831,1.945];紫花针茅种群的信息维数区间为[1.590,1.899],醉马草种群的信息维数区间为[1.633,1.913]。在放牧率4.34 AUM/hm2时,紫花针茅种群与醉马草种群空间占据差值达到最大,信息维数相对较低,种群分布相对均匀,格局变化相对缓慢,经济效益与生态效益相平衡,最适合管理牧场。 相似文献
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This study uses a geographical information system (GIS) and statistical analysis to look for patterns in referrals to a British
cancer genetics service. In this case, familial cancers are taken to be those that can develop when an individual inherits
DNA mutations that cause an increased risk of cancer. Between 1998 and 2006 the Cancer Genetics Service for Wales received
nearly 11,000 referrals for patients resident in Wales and it is the service database recording those referrals which is the
subject of this secondary analysis. Using postcodes to match referred patients to areas, deprivation scores were assigned.
Referral rates per 10,000 head of population across the 8-year study period by unitary authority are presented, as is information
on referrals from primary and secondary care sources by year. Each patient referred has their family history of cancer recorded
and is assigned to a risk category; high, medium or average. There are correlations between number of GPs (General Practitioners)
in a practice, number of patients referred from a practice, and deprivation as measured by the overall Welsh Index of Multiple
Deprivation 2005, such that the two former factors increase as deprivation decreases. Over time there were changes in referral
sources, with referrals from primary care overtaking those from secondary care in percentage and absolute terms. There were
also changes in the types of cancer referred, risk categories seen and to which centre referrals were made. Referral patterns
reveal an inverse relationship between deprivation and health service availability and use. 相似文献
100.