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141.
八叉树结构是由四叉树结构推广到三维空间而形成的一种3D栅格数据结构,其树型结构在空间分解上具有很强的优势,为了有效地进行大量点云数据的存储和管理,重点讨论了线性八叉树编码技术。 相似文献
142.
《Research Policy》2022,51(7):104550
Applying a within-firm perspective to the topic of the division of innovative labor, I explore the organization of scientific discovery at the firm level — specialized or integrated with invention. Using data on inventors and authors related to U.S. publicly-traded science-performing firms for the period 1980–2015, the paper deepens our understanding of the determinants and the tradeoffs associated with the strategic choice of scientific discovery organization. I show that integration is related to a tradeoff between short-term applied R&D and long-term fundamental R&D; while integration is beneficial for invention, it has adverse effects on its scientific output, which decrease invention in the long run. The negative relationship between integration and publication reduces the direct increase in patents due to integration by approximately 90%. To better understand firms’ R&D organizational choice, I present internal and external factors that have implications on the benefits and costs associated with integration: reliance on science, stage of technology, external market for technology, and R&D spillins. Finally, I present consistent implications in terms of market value and show that value creation is related to organizational structure. 相似文献
143.
Wenbo Pang Xu Cheng Haojie Zhao Xiaogang Guo Ziyao Ji Guorui Li Yiming Liang Zhaoguo Xue Honglie Song Fan Zhang Zheng Xu Lei Sang Wen Huang Tiefeng Li Yihui Zhang 《国家科学评论(英文版)》2020,7(2):342
The manufacture of 3D mesostructures is receiving rapidly increasing attention, because of the fundamental significance and practical applications across wide-ranging areas. The recently developed approach of buckling-guided assembly allows deterministic formation of complex 3D mesostructures in a broad set of functional materials, with feature sizes spanning nanoscale to centimeter-scale. Previous studies mostly exploited mechanically controlled assembly platforms using elastomer substrates, which limits the capabilities to achieve on-demand local assembly, and to reshape assembled mesostructures into distinct 3D configurations. This work introduces a set of design concepts and assembly strategies to utilize dielectric elastomer actuators as powerful platforms for the electro-mechanically controlled 3D assembly. Capabilities of sequential, local loading with desired strain distributions allow access to precisely tailored 3D mesostructures that can be reshaped into distinct geometries, as demonstrated by experimental and theoretical studies of ∼30 examples. A reconfigurable inductive–capacitive radio-frequency circuit consisting of morphable 3D capacitors serves as an application example. 相似文献
144.
145.
BackgroundPlanctomycetes is a phylum of biofilm-forming bacteria with numerous biosynthetic gene clusters, offering a promising source of new bioactive secondary metabolites. However, the current generation of chemically defined media achieves only low biomass yields, hindering research on these species. We therefore developed a chemically defined medium for the model organism Planctopirus limnophila to increase biomass production.ResultsWe found that P. limnophila grows best with a 10 mM sodium phosphate buffer. The replacement of complex nitrogen sources with defined amino acid solutions did not inhibit growth. Screening for vitamin requirements revealed that only cyanocobalamin (B12) is needed for growth. We used response surface methodology to optimize the medium, resulting in concentrations of 10 g/L glucose, 34 mL/L Hutner’s basal salts, 23.18 mM KNO3, 2.318 mM NH4Cl and 0.02 mg/L cyanocobalamin. The analysis of amino acid consumption allowed us to develop a customized amino acid solution lacking six of the amino acids present in Aminoplasmal 10%. Fed-batch cultivation in a bioreactor using the optimized medium achieved a final ΔOD600 of 46.8 ± 0.5 after 108 h, corresponding to a cell dry weight of 13.6 ± 0.7 g/L.ConclusionsThe optimized chemically defined medium allowed us to produce larger amounts of biomass more quickly than reported in earlier studies. Further research should focus on triggering P. limnophila biofilm formation to activate the gene clusters responsible for secondary metabolism.How to cite: Kruppa OC, Gerlach D, Fan R, et al. Development of a chemically defined medium for Planctopirus limnophila to increase biomass production. Electron J Biotechnol 2021;54. https://doi.org/10.1016/j.ejbt.2021.09.002. 相似文献
146.
《Research Policy》2023,52(8):104821
Where do firms innovate? Mapping their locations and directions in technological space is challenging due to its high dimensionality. We propose a new method to characterize firms’ inventive activities via topological data analysis (TDA) that represents high-dimensional data in a shape graph. Applying this method to 333 major firms’ patents in 1976–2005 reveals hitherto undocumented industry dynamics: some firms remain undifferentiated; others develop unique portfolios. Firms with unique trajectories, which we define and measure graph-theoretically as “flares” in the Mapper graph, tend to perform better. This association is statistically and economically significant, and continues to hold after we control for portfolio size, firm survivorship, and industry classification. 相似文献
147.
Jiawei Huang Mahda M. Bagher Heather Dohn Ross Nathan Piekielek Jan Oliver Wallgrün Jiayan Zhao 《Journal of Map & Geography Libraries》2018,14(1):40-63
Libraries have been the key to preserving culture and historic legacy for centuries. One such treasure cataloged in The Pennsylvania State University (Penn State) Libraries is a collection of over 33,000 Sanborn? Fire Insurance Maps. Originally kept safe in metal drawers, the library has embarked on a journey to digitize this abundance of information, combine it with other media such as photographs, and make it accessible through a web interface. Inspired by these efforts, we accessed this information and took it to the next level. Using state of the art 3D modeling and immersive technologies, we created a historic 3D model and immersive experiences of Penn State, exemplarily for the 1922 campus. The resulting experiences can be accessed through the web but also through head mounted displays (HMDs) and mobile phones in combination with VR viewers such as the Google Cardboard. Additionally, they can be used anywhere in the world or on the campus itself as a way to enable remote and in situ experiences and learning. Immersive experiences let us connect to the past, the present and the future, and as such offer value to digital cultural heritage efforts. 相似文献
148.
以WL新材料公司研发团队的绩效评估为研究对象,通过对影响研发团队绩效的关键因子进行提取,并基于层次分析法对因子的权重进行赋值,最后根据专家评估组给出的打分,综合评定出研发团队的绩效得分,将绩效得分结果以面谈的方式反馈给研发团队,通过持续的绩效改进来不断提供该企业研发团队的绩效水平. 相似文献
149.
以分析研发联盟中的风险为切入点,借用第三方担保在主权国家间条约或联盟中的风险防范机制,研究第三方担保对于研发联盟风险防范的有效作用。 相似文献
150.
以洗车水枪为例,详细阐述了逆向建模的流程,并利用逆向工程软件GeomagicStudio软件和Geomagic Design X软件对扫描数据进行处理,得到了高质量的三维模型。该方法即可获得高质量的三维模型,还可缩短产品开发周期,具有较好的应用价值。 相似文献