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基于扫描数据的真实人体建模与动画

Journal of Computer Science & Technology 2004年第C期19卷 60-60页

三维人体模型的建立是当前一大研究热点。它在人机系统工程、服装行业、医学研究以及虚拟现实等领域有着广阔的应用前景。然而，要建立体形、外貌和运动都逼真的人体模型是非常困难的。在几何建模方面，目前很多方法利用的是常规的人体... 详细信息

三维人体模型的建立是当前一大研究热点。它在人机系统工程、服装行业、医学研究以及虚拟现实等领域有着广阔的应用前景。然而，要建立体形、外貌和运动都逼真的人体模型是非常困难的。在几何建模方面，目前很多方法利用的是常规的人体测量数据和统计资料，过度简化了外形尺寸。

关键词：人体建模动画数据虚拟现实扫描几何建模人机系统医学研究运动过度

A Time-Domain Numerical Simulation for Free Motion Responses of Two Ships Advancing in Head Waves

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China Ocean Engineering 2024年第3期38卷 519-530页

作者： PAN Su-yong CHENG yong School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The constant panel method within the framework of potential flow theory in the time domain is developed for solving the hydrodynamic interactions between two parallel ships with forward speed.When solving problems within a time domain framework,the free water surface needs to simultaneously satisfy both the kinematic and dynamic boundary conditions of the free water surface.This provides conditions for adding artificial damping layers.Using the Runge−Kutta method to solve equations related to time.An upwind differential scheme is used in the present method to deal with the convection terms on the free surface to prevent waves upstream.Through the comparison with the available experimental data and other numerical methods,the present method is proved to have good mesh convergence,and satisfactory results can be obtained.The constant panel method is applied to calculate the hydrodynamic interaction responses of two parallel ships advancing in head waves.Numerical simulations are conducted on the effects of forward speed,different longitudinal and lateral distances on the motion response of two modified Wigley ships in head waves.Then further investigations are conducted on the effects of different ship types on the motion response.

关键词： ship motions time domain simulation forward speed different distances wave loads

Optimizing multi-parameter distributed fiber sensors:a hybrid Rayleigh-Brillouin-Raman System approach

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Light(Science & Applications) 2024年第3期13卷 393-395页

作者： Kwang yong Song Dept.of Physics Chung-Ang University84 Heukseok-roDongjak-guSeoul 06974Korea

An optimized single-end hybrid Rayleigh,Brillouin,and Raman distributed fiber sensing system has been developed for simultaneous measurement of multiple parameters.This system integrates 3-bit pulse coding for the Raman signal and the Brillouin amplification of the Rayleigh-backscattered signal,discriminating strain,temperature,and vibration using a single sensing fiber.

关键词： fiber Rayleigh signal

Recent advances in multifunctional shape memory photonic crystals and practical applications

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Nano Research 2024年第1期17卷 79-96页

作者： yong Qi Shufen Zhang State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China

Shape memory photonic crystals(SMPCs)are smart composite materials with changeable structural color integrated by shape memory polymer and photonic crystals.SMPC can produce one or more temporary shapes through nanoscale deformation,memorizing current states.SMPC can be recovered to their original shapes or some intermediate states under external stimuli,accompanied by the variation of structural color.As porous carriers with built-in sensing properties,SMPCs promoted the interdisciplinary development of nanophotonic technology in materials science,environmental engineering,biomedicine,chemical engineering,and mechanics.Herein,the recent progress on multifunctional SMPCs and practical applications,including traditional and cold programmable SMPCs,is summarized and discussed.The primary concern is shape programming at the nanoscale that has demonstrated numerous attractive functions,including smart sensing,ink-free printing,solvent detection,reprogrammable gradient wetting,and controllable bubble transportation,under variations of the surface nanostructure.It aims to figure out the nanoscale shape memory effects on structural color conversion and additional performance,inspiring the fabrication of the next generation of SMPCs.Finally,perspectives on future research directions and applications are also presented.It is believed that multifunctional SMPCs are powerful nanophotonic tools for the interdisciplinary development of numerous disciplines in the future.

关键词： photonic crystal shape memory structural color cold programmable shape recovery

Overview of radar detection methods for low altitude targets in marine environments

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Journal of Systems Engineering and Electronics 2024年第1期35卷 1-13页

作者： YANG yong YANG Boyu School of Electronic Science National University of Defense TechnologyChangsha 410073China

In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath scattering.The performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments.

关键词： radar sea clutter multipath scattering detection low altitude target

Asymmetric reversible structural switching of a diene coordination polymer promoted by UV-visible light

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Science China Chemistry 2024年第2期67卷 536-541页

作者： yong Wang Qiaoqiao Zhang yong-yong Cao Qi Liu Brendan F.Abrahams Jian-Ping Lang College of Chemistry Chemical Engineering and MaterialsSoochow UniversitySuzhou215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China College of Biological Chemical Science and EngineeringJiaxing UniversityJiaxing314001China School of Chemistry University of MelbourneVictoria3010Australia

In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward processes.In applications for which switching behavior is required,it is desirable that the reversible reaction goes as close to symmetric as possible;however,such systems are uncommon.Herein,we report an example of ultraviolet(UV)-visible light-regulated asymmetric reversible structural switching involving a diene-based coordination polymer,CP1 and its monocyclobutane product,CP1a.It is possible to cycle at least ten times through a forward [2+2] photocycloaddition reaction and the reverse,photocleavage reaction.A single cycle can be completed within a few minutes.The transformation is accompanied by fast and distinct fluorescence changes,arising from optimisation of the reaction conditions.Density functional theory calculations allow rationalisation of the asymmetric reversible transformation between CP1 and CP1a rather than between CP1 and its dicyclobutane product CP1b.This work provides a clear illustration of reversible structural switching which approaches symmetric behaviour with respect to reaction rate and stimuli.The insights gained from this work also assist in the design of fast,reversible switching materials.

关键词： asymmetrical reversible structural switching coordination polymer photocycloaddition UV-visible light-controlled fluorescence switching

The Role of Adipose Tissue-derived Exosomes in Chronic Metabolic Disorders

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Current Medical Science 2024年第3期44卷 463-474页

作者： Rui HE yong CHEN Division of Endocrinology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Laboratory of Endocrinology & Metabolism Key Laboratory of Vascular Aging of the Ministry of EducationTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Branch of National Clinical Research Center for Metabolic Diseases Wuhan430030China

Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body metabolism.Exosomes are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(AT Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine mechanisms.However,the roles of AT Exos in crosstalk with metabolic organs remain to be fully elucidated.In this review,we summarize the latest research progress on the role of AT Exos in the regulation of metabolic disorders.Moreover,we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.

关键词： exosome adipose tissue obesity diabetes chronic metabolic disorder miRNA

Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： Xing Chen yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater weapons.This paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in water.The findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying exponentially.Increasing the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the JPC.The optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in water.Material density plays a crucial role in the velocity decay pattern of the JPC during penetration.JPC with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are similar.Consequently,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge warhead.Finally,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Long-term operation optimization of circulating cooling water systems under fouling conditions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 255-267页

作者： Jiarui Liang yong Tian Shutong Yang yong Wang Ruiqi Yin Yufei Wang School of Chemical Engineering and Environment China University of PetroleumBeijing102249China CHN Energy Xinjiang Chemical Co. LTDUrumqi830092China College of Mechanical and Transportation Engineering China University of PetroleumBeijing 102249China

Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization.

关键词： Computer simulation Circulating water system Fouling Concentration cycle Optimization Variable frequency drive