为解决轨道交通工程的建筑信息模型(Building Information Modeling,BIM)体量庞大导致的数据整合难度大的问题,本文提出了BIM轻量化技术。通过改进二次误差测度算法在降低模型复杂度的同时保留模型的细节和几何特征,并采用三角网格相似...为解决轨道交通工程的建筑信息模型(Building Information Modeling,BIM)体量庞大导致的数据整合难度大的问题,本文提出了BIM轻量化技术。通过改进二次误差测度算法在降低模型复杂度的同时保留模型的细节和几何特征,并采用三角网格相似性度量算法减少相似构件的存储次数,从而降低模型存储的数据量;对模型数据进行拆分和分步传输,从而提升模型传输速度;通过局部重建和动态剔除冗余构件优化显示效率,并对模型进行分区渲染,从而减少运行耗时。经在广州地铁18号线磨碟沙站应用,采用该技术将大体量模型轻量化后,占用的存储空间减少15.71%~35.87%,网格数量减少21.46%~31.65%,传输速度提高2.5~10.0 MB/s,且模型主要几何构件能以50.0~59.8帧/s的速度在自主开发的图形平台上清晰展示。展开更多
Surface display is effectively utilized to construct a whole-cell biocatalyst.Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast.Here,the cDNA sequence of Rhi...Surface display is effectively utilized to construct a whole-cell biocatalyst.Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast.Here,the cDNA sequence of Rhizopus oryzae lipase (ROL) was optimized and synthesized according to the codon bias of Saccharomyces cerevisiae,and based on the Saccharomyces cerevisiae cell surface display system with α-agglutinin as an anchor,recombinant yeast displaying fully codon-optimized ROL with high activity was successfully constructed.Compared with the wild-type ROL-displaying yeast,the activity of the codon-optimized ROL yeast whole-cell biocatalyst (25 U/g dried cells) was 12.8-fold higher in a hydrolysis reaction using p-nitrophenyl palmitate (pNPP) as the substrate.To our knowledge,this was the first attempt to combine the techniques of yeast surface display and codon optimization for whole-cell biocatalyst construction.Consequently,the yeast whole-cell ROL biocatalyst was constructed with high activity.The optimum pH and temperature for the yeast whole-cell ROL biocatalyst were pH 7.0 and 40 °C.Furthermore,this whole-cell biocatalyst was applied to the hydrolysis of tributyrin and the resulted conversion of butyric acid reached 96.91% after 144 h.展开更多
文摘为解决轨道交通工程的建筑信息模型(Building Information Modeling,BIM)体量庞大导致的数据整合难度大的问题,本文提出了BIM轻量化技术。通过改进二次误差测度算法在降低模型复杂度的同时保留模型的细节和几何特征,并采用三角网格相似性度量算法减少相似构件的存储次数,从而降低模型存储的数据量;对模型数据进行拆分和分步传输,从而提升模型传输速度;通过局部重建和动态剔除冗余构件优化显示效率,并对模型进行分区渲染,从而减少运行耗时。经在广州地铁18号线磨碟沙站应用,采用该技术将大体量模型轻量化后,占用的存储空间减少15.71%~35.87%,网格数量减少21.46%~31.65%,传输速度提高2.5~10.0 MB/s,且模型主要几何构件能以50.0~59.8帧/s的速度在自主开发的图形平台上清晰展示。
基金Project supported by the National High-Tech R & D Program (863) of China (No. 2006AA10Z308)the National Science Foundation of China (No. 20776130)+1 种基金the Zhejiang Provincial Natural Science Foundation of China (No. Y4090309)the Zhejiang Provincial Science and Technology Program of China (No. 2009C32009)
文摘Surface display is effectively utilized to construct a whole-cell biocatalyst.Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast.Here,the cDNA sequence of Rhizopus oryzae lipase (ROL) was optimized and synthesized according to the codon bias of Saccharomyces cerevisiae,and based on the Saccharomyces cerevisiae cell surface display system with α-agglutinin as an anchor,recombinant yeast displaying fully codon-optimized ROL with high activity was successfully constructed.Compared with the wild-type ROL-displaying yeast,the activity of the codon-optimized ROL yeast whole-cell biocatalyst (25 U/g dried cells) was 12.8-fold higher in a hydrolysis reaction using p-nitrophenyl palmitate (pNPP) as the substrate.To our knowledge,this was the first attempt to combine the techniques of yeast surface display and codon optimization for whole-cell biocatalyst construction.Consequently,the yeast whole-cell ROL biocatalyst was constructed with high activity.The optimum pH and temperature for the yeast whole-cell ROL biocatalyst were pH 7.0 and 40 °C.Furthermore,this whole-cell biocatalyst was applied to the hydrolysis of tributyrin and the resulted conversion of butyric acid reached 96.91% after 144 h.
