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Novel developments in computational spectropolarimeter

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Light(Science & Applications) 2023年第3期12卷 321-322页

作者： En-lin Hsiang Shin-Tson Wu College of Optics and Photonics University of Central FloridaOrlandoFL 32816USA

Compared to conventional bulky spectropolarimeters,computational spectropolarimeters which reconstruct light-field information such as polarization and spectrum in a compact form factor,are critical equipment enabling new *** key component of a computational spectropolarimeter is a tunable light-field modulator,in which liquid crystal-based device is a promising *** varying the applied voltage,the tunable liquid crystal metasurface can modulate the phase and spectral information of the incident light,and after a few trials,this important information can be decoded *** a novel approach paves the foundation for developing compact and low-cost spectropolarimetric imaging devices with widespread applications in biomedical imaging,remote sensing,and optical communications.

关键词： tunable polarization modulator

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维普期刊数据库

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红外热成像无损检测缺陷的一种新方法

红外与毫米波学报 2000年第6期19卷 457-459页

作者：梅林王裕文薛锦西安交通大学机械工程学院陕西西安710049

通过脉冲加热阶段的红外无损检测一维理论模型 ,提出了一种评估缺陷深度信息的新算法 ,并给出了有限元模拟检测结果 ,分析了缺陷大小及脉冲加热时间对检测结果的影响、分析表明。

关键词：红外热成像无损检测数学模型有限元

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麦积山瑞应寺壁画初识

敦煌研究 2007年第4期 48-54,120-121页

作者：闫瑜林梅甘肃工业职业技术学院甘肃天水741025 麦积山石窟艺术研究所甘肃天水741020

本文从阅读麦积山瑞应寺相关文献过程中,发现并探讨论证了瑞应寺壁画涉及密教内容及相关问题,即瑞应寺壁画布局、内容及考释,并由大雄宝殿顶梁墨书题记考察其年代。

关键词：瑞应寺壁画密教影响题记年代

Role of gap junction and connexin-43 in hypoxic-ischemic brain damage

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Neural Regeneration Research 2006年第6期1卷 560-562页

作者： Jieying lin Niyang lin Department of Pediatrica First Hospital Affiliated to Medical College of Shantou University Shantou 515041 Guangdong Province China

OBJEETIVE ： Gap junction （GJ） is the structural basis tor direct intercellular communication OT nerve CellS. Connexin （Cx） is the protein subunit for constructing GJ channel. Among them, Cx43 is closely related with nervous system. Both Cx43 and nervous system play an important role in the pathophysiological development of hypoxic-ischemic injury. We are in attempt to investigate G J, Cx43 and their correlations with hypoxic-ischemic brain damage by research. DATA SOURCES ： Using the terms ＂ brain gap junction＂ in English and ＂gap junction＂ in Chinese, we searched the Medline database and Chinese BioMedical Literature Database as well as China Hospital Knowledge Database to identify the articles published from 1996 to 2006 about GJ and brain hypoxic-ischemic injury. STUDY SELECTION ： The articles were selected firstly and abstracts of 250 articles were read through. Articles in which the experimental design met randomized controlled principle were included, and study articles and case reports with repetitive contents were excluded. DATA EXTRACTION ： Among 53 included correlative articles, 23 were excluded for repetitive contents and the other 30 were analyzed. DATA SYNTHESIS： GJ, widely existing in nervous system, plays a key role in maintaining normal differentiation and development as well as physiological function of brain tissue. GJ channel is a hydrophilic, Iow-selectivity and lowohmic channel, which can provide direct channel for intercellular substance transmission and information communication. It plays an important role in the differentiation and development of nerve cells and regulation of physiological function. The functions of GJ channel are regulated by many factors, which involved intracellular pH value, Ca^2＋ concentration, ATP concentration, phosphorylation of Cx, transchannel pressure, some neurohormonal factors, regulatory factors of protein and so on. Cx43 is the main component of GJ channel in the brain tissues. Its expression in the bra

关键词： brain damage nervous system diseases physiological function information communication gap junction nerve cells intracellular Ph value experimental design Knowledge Database

Large eddy simulation of aircraft wake vortex with self-adaptive grid method

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Applied Mathematics and Mechanics(English Edition) 2016年第10期37卷 1289-1304页

作者： Mengda lin Guixiang CUI Zhaoshun ZHANG Department of Engineering Mechanics School of Aerospace Tsinghua University

A self-adaptive-grid method is applied to numerical simulation of the evolu- tion of aircraft wake vortex with the large eddy simulation （LES）. The Idaho Falls （IDF） measurement of run 9 case is simulated numerically and compared with that of the field experimental data. The comparison shows that the method is reliable in the complex atmospheric environment with crosswind and ground effect. In addition, six cases with different ambient atmospheric turbulences and Brunt V^iis/il^i （BV） frequencies are com- puted with the LES. The main characteristics of vortex are appropriately simulated by the current method. The onset time of rapid decay and the descending of vortices are in agreement with the previous measurements and the numerical prediction. Also, sec-ondary structures such as baroclinic vorticity and helical structures are also simulated. Only approximately 6 million grid points are needed in computation with the present method, while the number can be as large as 34 million when using a uniform mesh with the same core resolution. The self-adaptive-grid method is proved to be practical in the numerical research of aircraft wake vortex.

关键词： large eddy simulation (LES) aircraft wake vortex self-adaptive grid

Motion and orientation of cylindrical and cubic particles in pipe flow with high concentration and high particle to pipe size ratio

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 664-671页

作者： Xiao-ke KU Jian-zhong lin Department of Mechanics Zhejiang University Hangzhou 310027 China College of Metrology Technology and Engineering China Jiliang University Hangzhou 310018 China

Lattice Boltzmann method was used to numerically investigate the motion and orientation distribution of cylindrical and cubic particles in pipe flow with high concentration and high particle to pipe size ratio. The transient impulse model of 3D collisions between particles and between particle and wall is proposed. The numerical results are qualitatively in agreement with and quantitatively comparable to the experiment data. The results show that the increases of both the cylindrical particle to pipe size ratio and the particle aspect ratio decrease the rotation about all axes. All rotations of cubic particles decrease with increasing the particle concentration. The cubic particles, rotating more drastically in the flow with large Reynolds number, rotate faster than the cylindrical particles with the same size. The cylindrical particles align with the flow direction more obviously with decreasing Reynolds numbers. However, the orientations of cubic particles are spread all over the range with no significant difference in magnitude, and the Reynolds numbers have no obvious effect on the orientations of cubic particles.

关键词： Particulate flow Angular velocity Orientation Lattice Boltzmann method

Topology optimization design of micro-mass sensors for maximizing detection sensitivity

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Acta Mechanica Sinica 2015年第4期31卷 536-544页

作者： Zheqi lin Xuansheng Wang Yiru Ren School of Information Science and Technology Sun Yat-sen University Shenzhen Research Institute of Sun Yat-sen University Sun Yat-sen University College of Mechanical and Vehicle Engineering Hunan University

Micro-mass sensors have attracted increasing attention in the field of biomolecular and chemical detec- tion. It has been found that the size, shape, and geometry of the structure may affect the performance of the sensor. As a result, a topology optimization methodology is proposed in this paper for the design of micro-mass sensors. A phase- field function controlled by nodal variables and finite element shape functions is used to describe the configuration of a sen- sor in the constructed optimization problem. The design goal is to maximize the mass detection sensitivity. On the basis of these formulations, an optimization algorithm is constructed using the finite element method and the method of moving asymptotes. Numerical examples are presented to demon- strate the validity of the proposed problem formulation. The results suggest that the performance of the micro-mass sensor can be improved by using the proposed approach.

关键词： Topology optimization Mass detectionsensitivity Finite element method Phase-field functionMicro-mass sensor

Practical compensation for nonlinear dynamic thrust measurement system

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Chinese Journal of Aeronautics 2015年第2期28卷 418-426页

作者： Chen lin Chen Jie Li Jianxun Department of Automation Shanghai Jiao Tong University Shanghai Institute of Space Propulsion Shanghai Academy of Spaceflight Technology

The real dynamic thrust measurement system usually tends to be nonlinear due to the complex characteristics of the rig, pipes connection, etc. For a real dynamic measuring system, the nonlinearity must be eliminated by some adequate methods. In this paper, a nonlinear model of dynamic thrust measurement system is established by using radial basis function neural network （RBF-NN）, where a novel multi-step force generator is designed to stimulate the nonlinearity of the system, and a practical compensation method for the measurement system using left inverse model is proposed. Left inverse model can be considered as a perfect dynamic compensation of the dynamic thrust measurement system, and in practice, it can be approximated by RBF-NN based on least mean square （LMS） algorithms. Different weights are set for producing the multi-step force, which is the ideal input signal of the nonlinear dynamic thrust measurement system. The validity of the compensation method depends on the engine＇s performance and the tolerance error 0.5%, which is commonly demanded in engineering. Results from simulations and experiments show that the practical compensation using left inverse model based on RBF-NN in dynamic thrust measuring system can yield high tracking accuracy than the conventional methods.

关键词： Digital compensation Dynamic thrust measure-ment system Identification Left inverse model Nonlinear model Radial basis function neuralnetwork

The Hong Kong-Zhuhai-Macao Island and Tunnel Project

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Engineering 2017年第6期3卷 783-784页

作者： Ming lin Wei lin Hang Kong-Zhuhai-Macao Island and Tunnel Project General Management Office China

The Hong Kong-Zhuhai-Macao （HZM） Bridge is located at the Pearl River estuary and has a total length of 55 km. The HZM Bridge＇s main navigational crossing is by way of two 100 000 m2 artificial islands and a 6.7 km...

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