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Quantification of In Vivo Epidermal Keratinocyte Architecture Associated with the Signs of Skin Aging and the Skin Benefit Evaluation by Application of Galactomyces Ferment Filtrate (Pitera)-Containing Skin Care Product
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作者 Kukizo Miyamoto Yoko Munakata +4 位作者 Keisuke Fujii Chenlu Lei Ley Yang Suda Sudarsana Masutaka Furue 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第1期12-28,共17页
Background: Aged skin exhibits visual alterations such as wrinkles, rough texture, pore dilation, and dull skin tone, as well as physiological aging, namely, decreased hydration and increased transepidermal water loss... Background: Aged skin exhibits visual alterations such as wrinkles, rough texture, pore dilation, and dull skin tone, as well as physiological aging, namely, decreased hydration and increased transepidermal water loss (TEWL). Recent advances in coherence tomography have also revealed that skin aging affects in vivo epidermal keratinocyte architecture. However, the interconnectivity between spatial architectural aging and visual/physiological aging parameters remains largely unknown. Purpose: To elucidate whether the tomographic keratinocyte architectural aging is correlated with visual and physiological skin aging parameters and to quantitatively evaluate the improvements of the architectural, visual, and physiological aging parameters by the daily treatment of the skin care formula containing Galactomyces Ferment Filtrate (GFF, 8X Pitera<sup>TM</sup>). Method: We measured the in vivo keratinocyte cellular architecture with two-photon stereoscopic tomography obtaining by-layer epidermal section images in 78 Asian females of various ages. Visual aging parameters were analyzed using a portable image capture system. Hydration and TEWL were also assessed. The anti-aging effects of GFF-containing skin moisturizer (SK-II LXP Cream<sup>TM</sup>) were also examined in two studies after twice-daily application for 2 (N = 35) and 4 (N = 32) weeks. Results: As for the keratinocyte cellular architecture, skin aging was significantly associated with decreased cell density and increased cell uniformity. These architectural aging parameters were significantly correlated with visual and physiological aging parameters, namely, rough texture, wrinkles, pore dilation, dull skin tone, dehydration, and increased TEWL. The strong interconnectivity allowed us to develop formulae to estimate the keratinocyte architecture from visual aging parameters. Moreover, twice-daily application of SK-II significantly improved the keratinocyte architecture associated with multiple skin aging visual and physiological parameters. Conclusion: Skin aging is a process involving mutual interconnections among epidermal keratinocyte cellular architecture, visual, and physiological parameters. The GFF-containing moisturizer SK-II effectively improves spatial architecture of keratinocytes in epidermis and these evaluated skin aging parameters in a new trajectory over the course of treatment. . 展开更多
关键词 Facial Skin Aging In Vivo Keratinocyte Cellular Architecture Visual Aging pa-rameter Dehydration INTERCONNECTIVITY New Trajectory Galactomyces Fer-ment Filtrate PiteraTM SK-II LXP CreamTM
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Study of the Effect of Operating Temperatures (1320 K, 1420 K and 1520 K) on the Vacant Sites of TiN Alloy in B2 Structure at 45%, 50% and 55% N by MEAM Method
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作者 Alain S. Dzabana Honguelet Yahnn J. Mighensle Mimboui +1 位作者 Ronolvie Bitho Ondongo Timothée Nsongo 《Advances in Materials Physics and Chemistry》 2023年第7期135-149,共15页
In this work, we have studied the vacancy formation energy of TiN alloy of structure B2 of size 10 × 10 × 10 for nitrogen percentages of 45%, 50% and 55% under the influence of temperature at 1320 K, 1420 K ... In this work, we have studied the vacancy formation energy of TiN alloy of structure B2 of size 10 × 10 × 10 for nitrogen percentages of 45%, 50% and 55% under the influence of temperature at 1320 K, 1420 K and 1520 K using the Modified Embedded Atom Method MEAM under the calculation code LAMMPS version 2020. This study has enabled us to understand the behavior of the TiN alloy under different nitrogen percentages in terms of total energy, vacancy formation energy, crystalline parameter, occupancy rate and order parameter. For total energy, we have shown that as temperature increases, total energy decreases, making it easier to obtain TiN at higher temperatures;reaching the value of -7344.9169 eV for the 55% nitrogen structure for the temperature of 1420 K. For the energy of formation, we have shown that the compounds obtained at 1320 K and 1520 K have a more considerable energy of formation than that obtained at 1420 K. The study of fractions and the order parameter showed us that the structure of TiN with 55% nitrogen is less likely, as the composition obtained is at most 53.35%. 展开更多
关键词 MEAM LAMMPS Code Molecular Dynamics Formation Energy Order pa-rameter Filling Rate FRACTION Alloy DEFECT Gap VACANCY
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基于Simulink的数控机床多惯量伺服进给系统的建模与仿真(英文) 被引量:2
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作者 沙丰永 高军 +2 位作者 李学伟 罗超 骆飞 《机床与液压》 北大核心 2015年第24期51-55,共5页
针对双惯量伺服进给系统对其中间环节分析不足、参数整定算法精度较低等问题,提出了一种多惯量伺服进给系统模块化建模的方法。将数控机床伺服进给系统转化为多惯量系统,分为电机、丝杠、工作台3个单元,单元间的连接件(联轴器和丝杠螺母... 针对双惯量伺服进给系统对其中间环节分析不足、参数整定算法精度较低等问题,提出了一种多惯量伺服进给系统模块化建模的方法。将数控机床伺服进给系统转化为多惯量系统,分为电机、丝杠、工作台3个单元,单元间的连接件(联轴器和丝杠螺母)均等效为柔性连接件。基于PID的三闭环控制系统,运用Matlab对永磁同步电机矢量控制系统模型、机械传动系统模型进行仿真,整定优化各项参数。仿真结果表明:模块化建模方法能够对多惯量伺服系统存在的问题进行精准分析,对系统中间连接环节具有更为有效的分析效果;提高了仿真模型以及参数整定算法的精度,且仿真效果较好。 展开更多
关键词 Dynamic modeling Multi-inertia system Flexible joint PERMANENT MAGNET SYNCHRONOUS Motor pa-rameter SETTING algorithm
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基于高拟真度模型的再入飞行器多学科优化 被引量:3
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作者 粟华 谷良贤 龚春林 《西北工业大学学报》 EI CAS CSCD 北大核心 2013年第3期339-344,共6页
针对新型飞行器子学科高度集成、学科间强烈耦合的设计特点,提出了一套基于高拟真度学科分析模型的高超声速飞行器多学科建模、集成和求解方法。采用依托CAD造型的参数化主模型架构技术进行几何特征建模,为气动、结构、气动热、质量等... 针对新型飞行器子学科高度集成、学科间强烈耦合的设计特点,提出了一套基于高拟真度学科分析模型的高超声速飞行器多学科建模、集成和求解方法。采用依托CAD造型的参数化主模型架构技术进行几何特征建模,为气动、结构、气动热、质量等学科分析模型构建提供基准支持;在此基础上研究了CAD、CAE等高拟真度学科分析模型在多学科设计优化中的集成应用方法,并以高超声速无动力滑翔再入飞行器为对象建立了支持高拟真度模型的多学科优化系统构架;最后采用响应面与梯度算法组合的搜索方式实现了再入飞行器的多学科优化。 展开更多
关键词 多学科优化 高拟真度模型 参数化主模型技术 参数化方法 集成技术 高超声速飞行器
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抑制初态误差影响的自适应迭代学习控制 被引量:11
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作者 吕庆 《自动化学报》 EI CSCD 北大核心 2015年第7期1365-1372,共8页
针对一类参数化高阶不确定非线性连续系统,设计迭代学习控制算法,以解决随机初态对系统跟踪性能产生负面影响的问题.结合滑模控制思想以及部分限幅参数学习律,控制算法在预设时间段内抑制随机初态偏差对系统跟踪性能的影响.经过预设时间... 针对一类参数化高阶不确定非线性连续系统,设计迭代学习控制算法,以解决随机初态对系统跟踪性能产生负面影响的问题.结合滑模控制思想以及部分限幅参数学习律,控制算法在预设时间段内抑制随机初态偏差对系统跟踪性能的影响.经过预设时间后,随着迭代次数的增加,系统的跟踪误差及其各阶导数一致收敛到零.且在整个运行时间段内,系统各个变量一致有界.此外,本文回避了非参数化不确定非线性系统在放宽迭代初值假设时常使用的Lipschitz假设条件,而采用类Lyapunov函数分析法设计迭代学习控制器.理论证明和仿真结果都说明了该算法的有效性. 展开更多
关键词 迭代学习控制 初始状态误差 参数化系统 滑模控制 自适应控制
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3-D velocity structure in the central-eastern part of Qilianshan 被引量:8
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作者 ZHANG Yuan-sheng(张元生) +7 位作者 ZHOU Min-du(周民都) RONG Dai-lu(荣代潞) ZHANG Li-guang(张立光) XU Zhong-qiu(许中秋) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第3期272-281,共10页
The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the ... The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the digital seismic network set up for a Sino-French cooperation program since 1996. The inversed velocity structure does primarily reflect some important features of the deep structure in the region and provide the scientific background for the further study of active tectonic structure and the calculation of earthquake parameters. 展开更多
关键词 central-eastern Qilianshan micro-earthquake observation 3-D velocity structure focal pa-rameters joint inversion
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SVD-LSSVM and its application in chemical pattern classification 被引量:2
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作者 TAO Shao-hui CHEN De-zhao HU Wang-ming 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第11期1942-1947,共6页
Pattern classification is an important field in machine learning; least squares support vector machine (LSSVM) is a powerful tool for pattern classification. A new version of LSSVM, SVD-LSSVM, to save time of selectin... Pattern classification is an important field in machine learning; least squares support vector machine (LSSVM) is a powerful tool for pattern classification. A new version of LSSVM, SVD-LSSVM, to save time of selecting hyper parameters for LSSVM is proposed. SVD-LSSVM is trained through singular value decomposition (SVD) of kernel matrix. Cross validation time of selecting hyper parameters can be saved because a new hyper parameter, singular value contribution rate (SVCR), replaces the penalty factor of LSSVM. Several UCI benchmarking data and the Olive classification problem were used to test SVD-LSSVM. The result showed that SVD-LSSVM has good performance in classification and saves time for cross validation. 展开更多
关键词 Pattern classification Structural risk minimization Least squares support vector machine (LSSVM) Hyper pa-rameter selection Cross validation Singular value decomposition (SVD)
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A novel analytic potential function applied to neutral diatomic molecules and charged lons 被引量:1
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作者 Chang-Feng Yu Chang-Jun zhu +2 位作者 Chong-Hui Zhang Li-Xun Song Qiu-Pin Wang 《Natural Science》 2010年第3期184-189,共6页
In this paper, a new method on constructing analytical potential energy functions is pre-sented, and from this a analytical potential en-ergy function applied to both neutral diatomic molecules and charged diatomic mo... In this paper, a new method on constructing analytical potential energy functions is pre-sented, and from this a analytical potential en-ergy function applied to both neutral diatomic molecules and charged diatomic molecular ions is obtained. This potential energy function in-cludes three dimensionless undetermined pa-rameters which can be determined uniquely by solving linear equations with the experimental spectroscopic parameters of molecules. The solutions of the dimensionless undetermined parameters are real numbers rather than com-plex numbers, this ensures that the analytical potential energy function has extensive uni-versality. Finally, the potential energy function is examined with four kinds of diatomic molecules or ions—homonuclear neutral diatomic mole-cule , and , homonuclear charged diatomic molecular ion , and , heter-nuclear neutral diatomic Molecule , and , heternuclear ch- arged diatomic Molecular ion , and ,as a conseque- nce, good results are obtained. 展开更多
关键词 DIATOMIC Molecules And Ions Potential Energy Function Force CONSTANTS SPECTROSCOPIC pa-rameters Phase Factor
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高效气动优化设计方法
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作者 傅林 左英桃 《航空计算技术》 2012年第4期68-71,76,共5页
基于CFD方法开展气动外形优化设计通常计算量较大,采用离散共轭方法计算目标函数梯度,建立了高效的飞机气动优化设计系统。采用NURBS方法对翼剖面几何外形的扰动量进行参数化,避免了对原始外形的拟合,建立了基于NURBS方法的机翼剖面参... 基于CFD方法开展气动外形优化设计通常计算量较大,采用离散共轭方法计算目标函数梯度,建立了高效的飞机气动优化设计系统。采用NURBS方法对翼剖面几何外形的扰动量进行参数化,避免了对原始外形的拟合,建立了基于NURBS方法的机翼剖面参数化方法。在复杂外形的优化设计中,动网格方法是关键技术之一,采用无限插值方法生成变形后的网格,并提出采用无限插值方法处理部件之间相贯线发生变化的情况。最后开展了翼身组合体+吊舱+挂架等复杂外形的优化设计,成功地减小了阻力,证明了方法的有效性。 展开更多
关键词 离散共轭 复杂外形 优化设计 动网格 相贯线 NURBS参数化
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Influence of the Structure Parameters on the Characteristics of Dynamic Mixer with Striped Channels
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作者 许正军 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期101-104,共4页
The influence of the structure parameters on the characteristics of dynamic mixer with striped channels is studied. As results indicate that, given the proper structure parameters, the output of the extruder can be in... The influence of the structure parameters on the characteristics of dynamic mixer with striped channels is studied. As results indicate that, given the proper structure parameters, the output of the extruder can be increased with low energy consumption and stable temperature. Furthermore, the mixing effect will be improved up to or even above that of spherical cavity mixer. 展开更多
关键词 DYNAMIC MIXER MIXING PROPERTY structure pa-rameters .
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基于CAXA(XP)的冷冲模标准图库开发 被引量:3
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作者 王元春 葛正浩 《机械设计与制造》 北大核心 2005年第7期165-166,共2页
介绍了基于CAXA(XP)的冷冲模参数化标准图库,以及运用此图库所需的系统配置和环境,并以一个标准件库系统的建立为例说明了CAXA标准图库建立中的几个关键问题:定义图符、元素定义、编辑图形、数据录入;同时介绍了图库的转换和图符驱动等... 介绍了基于CAXA(XP)的冷冲模参数化标准图库,以及运用此图库所需的系统配置和环境,并以一个标准件库系统的建立为例说明了CAXA标准图库建立中的几个关键问题:定义图符、元素定义、编辑图形、数据录入;同时介绍了图库的转换和图符驱动等过程。 展开更多
关键词 CAD CAXA—EB 标准件库 二次开发 参数化
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基于特征正交分解的材料微结构参数化表征模型及等效性能优化设计 被引量:1
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作者 郭志文 肖曼玉 夏凉 《应用数学和力学》 CSCD 北大核心 2017年第7期727-742,共16页
随着计算能力的不断发展,近年来基于材料微结构图像的材料等效性能数值模拟越来越受到学者们的重视.在此背景下,提出了一种针对材料微结构图像的高效参数化表征模型.通过特征正交分解(proper orthogonal decomposition,POD)对已有材料... 随着计算能力的不断发展,近年来基于材料微结构图像的材料等效性能数值模拟越来越受到学者们的重视.在此背景下,提出了一种针对材料微结构图像的高效参数化表征模型.通过特征正交分解(proper orthogonal decomposition,POD)对已有材料微结构图像数据进行特征分析,得到近似描述该类材料微结构的特征缩减基.应用移动最小二乘(moving least squares,MLS)法建立特征缩减基映射系数的响应面模型,拟合得到任意给定参量相应的缩减基映射系数.利用拟合缩减基系数可获得任意给定参量对应的微结构图像矩阵.该参数化表征模型被用于表征含椭球夹杂的两相材料(2-phase composite)的二维情形,并进一步应用于这类复合材料宏观等效力学性能的优化设计. 展开更多
关键词 材料微结构 特征正交分解 响应面 参数化模型 代理模型 均匀化 优化设计
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新型K型弯管锥头节点与传统管桁架节点的力学性能对比研究 被引量:2
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作者 谢成吉 申波 +5 位作者 李梦 赵庆阳 周世明 龙海芳 张晓辉 吴帮 《贵州大学学报(自然科学版)》 2014年第5期81-86,103,共7页
新型K型弯管锥头节点在超大跨度结构中具有节约材料、便于施工等优势,为了使该节点能应用于工程实践中,本文将其与普通管桁架弯管节点、变截面管桁架弯管节点进行了对比研究。通过有限元计算软件ANSYS进行参数化分析,对比了三类节点的... 新型K型弯管锥头节点在超大跨度结构中具有节约材料、便于施工等优势,为了使该节点能应用于工程实践中,本文将其与普通管桁架弯管节点、变截面管桁架弯管节点进行了对比研究。通过有限元计算软件ANSYS进行参数化分析,对比了三类节点的破坏模式、极限承载力、强屈比和延性系数。分析表明,K型弯管锥头节点的承载力明显优于其余两类节点,该节点也表现出与另外两类节点同样良好的强屈比与延性系数,可知该节点同样具有充足的安全储备和耗能性能。 展开更多
关键词 K型弯管锥头节点 非线性有限元分析 参数化 承载力
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基于CAA的机械零件参数化设计 被引量:11
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作者 许元付 郝博 《成组技术与生产现代化》 2013年第1期45-48,共4页
在分析目前三维参数化设计技术的基础上,阐述了零件参数化设计方法.并对CATIA的主要开发平台CAA进行了研究,分析了CAA的组成、原理和功能,提出了基于CAA的CATIA二次开发的基本方法.利用VC++,开发出与CATIA系统集成的二次开发技术,并运... 在分析目前三维参数化设计技术的基础上,阐述了零件参数化设计方法.并对CATIA的主要开发平台CAA进行了研究,分析了CAA的组成、原理和功能,提出了基于CAA的CATIA二次开发的基本方法.利用VC++,开发出与CATIA系统集成的二次开发技术,并运用具体开发实例进行了论证. 展开更多
关键词 二次开发 CATIA CAA 参数化设计
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