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Snapshot Mueller spectropolarimeter imager

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Microsystems & Nanoengineering 2023年第5期9卷 271-279页

作者： Tianxiang Dai Thaibao Phan evan W.wang Soonyang Kwon Jaehyeon Son Myungjun Lee Jonathan A.Fan Department of Electrical Engineering Stanford UniversityStanfordCA 94305USA Equipment R&D Team 4 Mechatronics ResearchSamsung Electronics Co.LtdGyeonggi-do 18848Republic of Korea

We introduce an imaging system that can simultaneously record complete Mueller polarization responses for a set of wavelength channels in a single image *** division-of-focal-plane concept combines a multiplexed illumination scheme based on Fourier optics together with an integrated telescopic light-field imaging ***-resolved imaging is achieved using broadband nanostructured plasmonic polarizers as functional pinhole *** recording of polarization and wavelength information on the image sensor is highly *** also develop a calibration approach based on a customized neural network architecture that can produce calibrated measurements in *** a proof-of-concept demonstration,we use our calibrated system to accurately reconstruct a thin film thickness map from a four-inch *** anticipate that our concept will have utility in metrology,machine vision,computational imaging,and optical computing platforms.

关键词： polarization image Snapshot

Effect of pumping chamber on performance of non-overload centrifugal pump

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Journal of Central South University 2015年第8期22卷 2989-2997页

作者：谷云庆牟介刚代东顺郑水华吴登昊蒋兰芳施瀚昱 wang evan College of Mechanical and Engineering Zhejiang University of Technology Engineering Research Center of Process Equipment and Its Re-manufacturing of Ministry of Education(Zhejiang University of Technology) Zhijiang College Zhejiang University of Technology Institut National Polytechnique of Grenoble Joseph Fourier University

In order to specify the characteristics of un-overloaded centrifugal pumps, the IH100-65-200 pump was chosen as the model pump. Different calculation models for centrifugal pumps were established under different pumping chamber sectional parameters. In the numerical simulation of the centrifugal pumps flow field, the shaft power, head, efficiency, and the changes of the internal flow field under different sectional areas and sectional shapes were studied with the RNG k-ε turbulence model, and the influence of the pumping chamber section characteristics of the non-overloaded centrifugal pumps were analyzed. The results show that sectional areas have a significant impact on the non-overload characteristics of centrifugal pumps. The shaft power and head of centrifugal pump are increasing with a lager sectional area, by which the gradient of head curves decreases. The efficiency is improved under a large flow rate condition, but the head and the efficiency are reduced at a small flow rate. It is also observed that the sectional shapes have less influence on the shaft power, the hydraulic performance and flow field characteristics of a centrifugal pump.

关键词：离心泵泵性能气室超负荷 k-ε湍流模型内部流场截面形状轴功率

Characteristics and mechanism investigation on drag reduction of oblique riblets

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Journal of Central South University 2017年第6期24卷 1379-1386页

作者：谷云庆范天星牟介刚吴登昊郑水华 evan wang College of Mechanical and Engineering Zhejiang University of TechnologyHangzhou 310014China Zhijiang College Zhejiang University of TechnologyHangzhou 310024China Institute National Polytechnique of Grenoble Joseph Fourier UniversityGrenoble 38031France

This work primarily focuses on the drag reduction characteristics and mechanism investigation of oblique riblets. First, a calculation model of the oblique riblets surface is established, and Reynolds stress model(RSM) turbulence model is used for numerical simulation of the oblique riblets flow field. Subsequently, the influence of inclination angle between flow direction and arrangement direction of riblets on friction resistance and drag reduction rate is further analyzed. Through the investigation of the distribution of shear stress, pressure stress and velocity in oblique riblets boundary layer, the oblique riblets drag reduction mechanism is finally revealed. Results show that, with increase of velocity and inclination angle, the pressure resistance increases obviously, along with the decreasing of the viscous resistance distinctly. The maximum drag reduction rate of the oblique riblets is 7.33%. Moreover, when the inclination angle increases, the wall shear stress reduces on oblique riblets surface; while differential pressure increases at both sides of oblique riblets tips. In addition, when inclination angle is small, the secondary vortex at oblique riblets tips will disappear soon. New vortices will be formed inside the oblique riblets and cause the decrease of viscosity resistance. Thus, oblique riblets show a better drag reduction effect and have an effective control on boundary layer.

关键词： oblique riblets drag reduction Reynolds stress model (RSM) secondary vortex numerical simulation

High-efficiency,large-area,topologyoptimized metasurfaces

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Light(Science & Applications) 2019年第1期8卷 749-757页

作者： Thaibao Phan David Sell evan W.wang Sage Doshay Kofi Edee Jianji Yang Jonathan A.Fan Department of Electrical Engineering Stanford UniversityStanfordCA 94305USA Department of Applied Physics Stanford UniversityStanfordCA 94305USA Universite Clermont Auvergne Institut PascalBP 10448F-63000 Clermont-FerrandFrance CNRS UMR 6602Institut PascalF-63177 AubiereFrance

Metasurfaces are ultrathin optical elements that are highly promising for constructing lightweight and compact optical *** their practical implementation,it is imperative to maximize the metasurface *** optimization provides a pathway for pushing the limits of metasurface efficiency;however,topology optimization methods have been limited to the design of microscale devices due to the extensive computational resources that are *** introduce a new strategy for optimizing large-area metasurfaces in a computationally efficient *** stitching together individually optimized sections of the metasurface,we can reduce the computational complexity of the optimization from high-polynomial to *** a proof of concept,we design and experimentally demonstrate large-area,high-numerical-aperture silicon metasurface lenses with focusing efficiencies exceeding 90%.These concepts can be generalized to the design of multifunctional,broadband diffractive optical devices and will enable the implementation of large-area,high-performance metasurfaces in practical optical systems.

关键词： topology optimization surface

A Study on Multivariable Interactions Concerning Radar Cross Section Reduction through Geometric Attributes

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Journal of Applied Mathematics and Physics 2024年第7期12卷 2582-2593页

作者： evan Sharp STEAM Institute Jacksonville University Jacksonville FL USA

This resolution 5 (25−1 factorial) study aimed to ascertain an understanding of the interactions between different geometries on the resulting Radar Cross Section (RCS) of a target. The results of the study are in line with the general understanding of the impact different geometries have on RCS but show that geometries can also influence the variance of measured RCS, and typical attributes that reduce RCS increase the variance of the measured RCS. Notably, an increased angle between the front face of a plate and the direction of the radar signal decreased RCS but increased the variance of the RCS measured.

关键词： Radar Cross Section RCS Geometrical Attributes Radar Stealth

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非光滑表面离心泵叶轮的流动减阻特性

上海交通大学学报 2016年第2期50卷 306-312页

作者：牟介刚代东顺谷云庆刘剑郑水华 wang evan 浙江工业大学机械工程学院杭州310014 约瑟夫傅立叶大学格勒诺布尔国立综合理工学院法国格勒诺布尔38031

为了分析非光滑表面对离心泵性能的影响,基于仿生凹坑表面的减阻特性,将凹坑型非光滑单元体排布于离心泵叶片的工作面,建立具有非光滑表面的叶轮离心泵的流动减阻特性分析模型,通过RNGk-ε湍流模型对离心泵内部流场进行数值模拟,分析具... 详细信息

为了分析非光滑表面对离心泵性能的影响,基于仿生凹坑表面的减阻特性,将凹坑型非光滑单元体排布于离心泵叶片的工作面,建立具有非光滑表面的叶轮离心泵的流动减阻特性分析模型,通过RNGk-ε湍流模型对离心泵内部流场进行数值模拟,分析具有非光滑表面叶轮的流动减阻特性,研究不同流量下非光滑表面对叶片近壁面的速度分布、剪应力和离心泵内部流场的影响.结果表明:凹坑型非光滑表面能够降低因黏性阻力产生的叶轮扭矩,其扭矩的最大降幅为5.8%;非光滑表面能够有效控制叶片近壁面边界层的流体流动,减小叶片的壁面剪应力;凹坑型非光滑表面能够降低离心泵叶轮内部流体的湍动程度,减小湍动产生的能量耗散,使叶轮内部的流体流动更加稳定并提高离心泵的效率.

关键词：离心泵非光滑表面减阻边界层

An Expanded View of Complex Traits:From Polygenic to Omnigenic

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四川生理科学杂志 2024年第1期46卷 139-139页

作者： evan A Boyle Department of Genetics Stanford University Stanford CA 94305 USA. Electronic address: eaboyle@stanford.edu. Department of Genetics Stanford University Stanford CA 94305 USA. Electronic address: yangili@stanford.edu. Department of Genetics Stanford University Stanford CA 94305 USA Department of Biology Stanford University Stanford CA 94305 USA Howard Hughes Medical Institute Stanford University Stanford CA 94305 USA. Electronic address: pritch@stanford.edu.

A central goal of genetics is to understand the links between genetic variation and ***,one might expect diseasecausing variants to cluster into key pathways that drive disease *** for complex traits,association signa... 详细信息

关键词： Traits cluster Complex

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 97-104页

作者： Mihai A.Bentan evan R.Reiter Richard M.Costanzo Daniel H.Coelho Department of Otolaryngology-Head&Neck Surgery Virginia Commonwealth University School of MedicineRichmondVirginiaUSA

Objective:The aim of this study was to review findings from a large prospective national database of chemosensory disturbances associated with coronavirus disease 2019(COVID-19)*** Sources:The Virginia Commonwealth University Smell and Taste Center national database of COVID-19 chemosensory ***:A series of online surveys,first opened on April 10,2020,was made accessible nationwide to any adult with sudden chemosensory dysfunction since January *** received subsequent follow-up surveys 14 days,1 month,3 months,and 6 months after *** additional survey was sent to all participants on May 28,2022 to assess long-term *** pertaining to demographics,symptoms,comorbidities,treatments,and life impact was ***:Of 363 participants who reported complete smell recovery,51.2%recovered within 1 month,70%within 3 months,and 79%within 6 months,while 8.8%took over 1 year to completely *** all participants,7.5%had no smell *** predictors of recovery included age<40,male gender,and the presence of nasal *** predictors included difficulty breathing and prior head *** participants reported a decrease in quality of life and the presence of potential safety hazards associated with decreased smell ***:Most subjects with COVID-19-related chemosensory dysfunction recover,with the majority noting complete recovery within weeks of *** aged over 40 years and female gender were associated with lower rates of recovery.A considerable number of participants reported significant impact on quality of life and safety.

关键词： anosmia COVID-19 smell

Investigation of HCAR2 antagonists as a potential strategy to modulate bovine leukocytes

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1567-1577页

作者： Laman K.Mamedova Kirby C.Krogstad Paiton O.McDonald Laxman Pokhrel Duy H.Hua evan C.Titgemeyer Barry J.Bradford Department of Animal Science Michigan State UniversityEast LansingMichigan 48824USA Department of Animal Sciences and Industry Kansas State UniversityManhattanKS 66506USA Comparative Medicine and Integrative Biology East LansingMI 48824USA Department of Chemistry Kansas State UniversityManhattanKS 66506USA

Background Dairy cows experiencing ketosis after calving suffer greater disease incidence and are at greater risk of leaving the herd. In vitro administration of beta-hydroxybutyric acid(BHBA;the primary blood ketone) has inhibitory effects on the function of bovine leukocytes. BHBA is a ligand of HCAR2 and the activation of these receptors promotes an anti-inflammatory response which may be related with immunosuppression observed in transition dairy cattle. The objective of this study was to identify and test antagonists for HCAR2 in bovine immune cells cultured with *** We observed expression of HCAR2 at the protein level within lymphocytes, monocytes, and granulocytes. The proportion of cells expressing HCAR2 tended to be greater in mid-lactation compared to early lactation cows;the increase was a result of increased proportion of T and B cells expressing HCAR2. Stimulation of HCAR2 with niacin or BHBA promoted Ca^(2+) mobilization in neutrophils and mononuclear cells. Mononuclear cells treated with BHBA had diminished intracellular Ca^(2+) responses when HCAR2 was knocked down by si RNA silencing, indicating Ca^(2+) mobilization was mediated by HCAR2 signaling. Two candidate antagonists for HCAR2, synthesized from niacin(NA-1 and NA-5), were tested;monocytes and neutrophils pre-treated with NA-1 and NA-5 had reduced Ca^(2+) mobilization after incubation with BHBA. Furthermore, NA-5 but not NA-1 prevented BHBA-associated reductions in cyclic *** We demonstrated that HCAR2 is present on bovine leukocytes and has greater expression later in lactation. We confirmed that BHBA and niacin derived HCAR2 antagonists alter bovine leukocyte activity. Our results demonstrate that both BHBA and niacin affect bovine leukocyte Ca^(2+) mobilization in a HCAR2-dependent manner.

关键词： Flow cytometry GPR109A HM74A Ketosis