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以摇瓶所得摄氧率为基准进行发酵放大 被引量:3
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作者 范代娣 俞俊棠 《生物工程学报》 CAS CSCD 北大核心 1996年第3期301-306,共6页
通过设计特殊摇瓶,用亚硫酸盐法测出摇瓶口纱布层氧通透率的基础上,在实际发酵情况下通过测定瓶内气、液相氧的变化得出其发酵过程中的摄氧率(OUR)及氧传递系数(K_La)。以特制摇瓶取得的菌体OUR为基准进行发酵过程和发酵罐的放大。通过... 通过设计特殊摇瓶,用亚硫酸盐法测出摇瓶口纱布层氧通透率的基础上,在实际发酵情况下通过测定瓶内气、液相氧的变化得出其发酵过程中的摄氧率(OUR)及氧传递系数(K_La)。以特制摇瓶取得的菌体OUR为基准进行发酵过程和发酵罐的放大。通过质谱仪在线检测及采样分析,研究了3种不同供气流量及搅拌转速下的放大结果。摇瓶与发酵罐在菌体OUR、菌体产量方面吻合很好,而在整个放大过程中,发现摇瓶与发酵罐内的氧传递系数(K_La)、溶解氧(c_L)差异较大。 展开更多
关键词 发酵学 摇瓶 摄氧率 发酵放大
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基于自适应权系数核方法的超光谱图像分类 被引量:2
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作者 林玉荣 王强 《红外与激光工程》 EI CSCD 北大核心 2011年第12期2535-2539,共5页
为了进一步提高支持向量机方法在超光谱图像分类中的性能,提出一种自适应加权核方法。该方法的关键是每个波段自适应权值的计算,考虑到超谱数据信息依波段分布不均匀及每个波段图像所含信息不同的特性,采用相邻波段图像间的相关系数及... 为了进一步提高支持向量机方法在超光谱图像分类中的性能,提出一种自适应加权核方法。该方法的关键是每个波段自适应权值的计算,考虑到超谱数据信息依波段分布不均匀及每个波段图像所含信息不同的特性,采用相邻波段图像间的相关系数及波段图像的归一化标准差之和作为该波段数据的权值,并给出了算法的具体实现步骤。实验结果表明:自适应加权核方法明显优于支持向量机方法,平均精度和总体精度分别提高了2.07%和2.28%,且对支持向量数目也有一定约减。 展开更多
关键词 超光谱图像分类 核方法 自适应 相关系数
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Development of Cubic Bezier Curve and Curve-Plane Intersection Method for Parametric Submarine Hull Form Design to Optimize Hull Resistance Using CFD
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作者 Deddy Chrismianto Ahmad Fauzan Zakki +1 位作者 Berlian Arswendo Dong Joon Kim 《Journal of Marine Science and Application》 CSCD 2015年第4期399-405,共7页
Optimization analysis and computational fluid dynamics (CFDs) have been applied simultaneously, in which a parametric model plays an important role in finding the optimal solution. However, it is difficult to create... Optimization analysis and computational fluid dynamics (CFDs) have been applied simultaneously, in which a parametric model plays an important role in finding the optimal solution. However, it is difficult to create a parametric model for a complex shape with irregular curves, such as a submarine hull form. In this study, the cubic Bezier curve and curve-plane intersection method are used to generate a solid model of a parametric submarine hull form taking three input parameters into account: nose radius, tail radius, and length-height hull ratio (L/H). Application program interface (API) scripting is also used to write code in the ANSYS DesignModeler. The results show that the submarine shape can be generated with some variation of the input parameters. An example is given that shows how the proposed method can be applied successfully to a hull resistance optimization case. The parametric design of the middle submarine type was chosen to be modified. First, the original submarine model was analyzed, in advance, using CFD. Then, using the response surface graph, some candidate optimal designs with a minimum hull resistance coefficient were obtained. Further, the optimization method in goal-driven optimization (GDO) was implemented to find the submarine hull form with the minimum hull resistance coefficient (Ct). The minimum C, was obtained. The calculated difference in (7, values between the initial submarine and the optimum submarine is around 0.26%, with the C, of the initial submarine and the optimum submarine being 0.001 508 26 and 0.001 504 29, respectively. The results show that the optimum submarine hull form shows a higher nose radius (rn) and higher L/H than those of the initial submarine shape, while the radius of the tail (r1) is smaller than that of the initial shape. 展开更多
关键词 submarine hull form parametric design cubic Bezier curve curve-plane intersection method hull resistance coefficeint parametric design goal-driven optimization (GDO) computational fluid dynamic (CFD) ANSYS
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气体输运过程的普遍表达式 被引量:1
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作者 林钜聪 《温州师范学院学报》 1998年第3期33-35,共3页
本文根据局域平衡条件,利用Maxwell速率分布律推导得到气体输运过程的一个普遍表达式,并对气体的三个具体输运系数作出讨论.
关键词 输运过程 输运系数 分子通量 平均碰撞距离 气体
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宽压力范围内液体等温状态方程的研究 被引量:1
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作者 傅和平 宁敏东 《大学物理》 北大核心 1996年第2期18-19,17,共3页
根据液体的压缩特性,运用数学方法导出了一个既适合高压、又适合低压范围的液体等温状态方程.对水、重水及汞在1-12000atm压力范围内的体积(比容)进行了计算,其计算值与实验值十分吻合,最大误差仅有0.058%.
关键词 比容 压缩系数 液体 等温状态方程
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