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Chinese Journal of Polymer Science 2018年第9期36卷 1084-1092页

作者： tian Xia Ya-Ping Qin Ting huang College of Material Science and Engineering Chongqing University of Technology

The effects of film thickness and composition ratio on the morphology evolution of polystyrene （PS）/poly（vinyl methyl ether）（PVME） blend thin films were investigated. Diverse morphology evolutions including droplet-matrix structure, hole emergence, bicontinuous structure formation, percolation-to-droplet transition could be observed under annealing in two-phase region, depending on film thickness and composition ratio. The mechanism for these morphology variations was related to the complex effects of phase separation, dewetting and preferential wetting. The comparison between the thickness of bottom PVME layer and the twice of gyration radius 2Rg（PVME） played a dominant role in morphology control. Only when the PS/PVME film had specific film thickness and compositional symmetry, phase separation and dewetting could happen in sequence.

关键词： Phase separation Dewetting Wetting

Large Eddy Simulation Study on the Turbulence and Flame Characteristics under Analogical Integral Scale and Turbulence Intensity of Turbulent Premixed Flames

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Journal of Thermal Science 2023年第1期32卷 488-501页

作者： WEI Xutao WANG Jinhua ZHANG meng huang Zuohua State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

Bunsen burner is a typical geometry for investigating the turbulence-flame *** most experimental studies,only turbulence intensity u′and integral scale l0 are used to characterize the turbulent flow field,regardless of the perforation geometry of perforated ***,since the geometry influences the developing process and vortex broken,the plate geometry has to be considered when discussing the flame-turbulence *** order to investigate conditions at the same l0 and u′using different geometries,large eddy simulation of CH_(4)/air flames with dynamic TF combustion model was *** model validation shows good agreement between Large Eddy Simulation(LES)and experimental *** the non-reacting flows,the Vortex Stretching of circular-perforated plate condition is always larger than that of slot-perforated plate condition,which comes from the stresses in the flow fields to stretch the vorticity *** reacting flows,at the root of the flame,the Vortex Stretching plays a major role,and the total vorticity here of circular-perforated plate condition is still larger(53.8%and 300%larger than that of the slot-perforated plate at x/D=0 and x/D=2.5,respectively).More small-scale vortex in circular-perforated plate condition can affect and wrinkle the flame front to increase the Probability Density Function(PDF)at large *** 3D curvature distributions of both cases bias to negative *** negative trend of curvatures at the instant flame front results from the Dilatation ***,the value of the Vortex Stretching and the Dilatation at the flame front of circular-perforated plate condition is obviously larger.

关键词： large eddy simulation integral scale turbulence intensity vorticity flame curvature

Intelligent Shape-Morphing Micromachines

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Research 2021年第1期2021卷 1018-1033页

作者： Qianying Chen Pengyu Lv Jianyong huang tian-Yun huang Huiling Duan State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceBIC-ESATCollege of EngineeringPeking UniversityBeijing 100871China CAPT HEDPSPeking UniversityBeijing 100871China

Intelligent machines are capable of switching shape configurations to adapt to changes in dynamic environments and thus have offered the potentials in many applications such as precision medicine,lab on a chip,and *** though the developments of smart materials and advanced micro/nanomanufacturing are flouring,how to achieve intelligent shapemorphing machines at micro/nanoscales is still significantly challenging due to the lack of design methods and strategies especially for small-scale shape *** review is aimed at summarizing the principles and methods for the construction of intelligent shape-morphing micromachines by introducing the dimensions,modes,realization methods,and applications of shape-morphing ***,this review highlights the advantages and challenges in shape transformations by comparing micromachines with the macroscale counterparts and presents the future outlines for the next generation of intelligent shape-morphing micromachines.

关键词： machines realization dimensions

Spontaneous relaxation of 2D passivation layer contributes to the aging-induced performance enhancement of perovskite solar cells

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Nano Research 2023年第1期16卷 521-527页

作者： Wenjing Yu Changjiang Liu Xiaoran Sun tian Hou Xin Yang Xin Wang Yue Yu Kai Chen Haijin Li Yuelong huang meng Zhang Institute of Photovoltaics Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

The aging-induced performance enhancement of the perovskite solar cells(PSCs)has been considered to be associated with the oxidation progress of the hole-transporting *** the influence of the structural evolution of the passivation layer is *** this work,a spontaneous relaxation of two-dimensional(2D)passivation layer with increased n-value structure is observed,which can be accelerated under ambient *** is demonstrated that device with relaxed 2D passivation layer exhibits reduced non-radiative recombination and optimized charge transfer property,contributing substantially to the aging-induced performance enhancement in 2D-3D heterostructured ***,a high fill factor of 84.15%of the devices is obtained with the relaxed 2D passivation layer,suggesting the spontaneous relaxation of 2D passivation layer is playing a key role in achieving high quality optoelectronic devices.

关键词： perovskite solar cell two-dimensional(2D)perovskite relaxation aging passivation

Melt-Water-Pulse (MWP) events and abrupt climate change of the last deglaciation

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Chinese Science Bulletin 2008年第18期53卷 2867-2878页

作者： huang EnQing tian Jun State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China

最后冰川的消失被巨大的冰表融化描绘，它导致平均海平面的上升类似于 120-140 m。至少三个主要 Melt-Water-Pulse (MWP ) 事件(19ka-MWP， MWP-1A 和 MWP-1B ) 为最后冰川的消失是可认识的，哪个持续从的 MWP-1A 事件类似于 14.2 到类... 详细信息

最后冰川的消失被巨大的冰表融化描绘，它导致平均海平面的上升类似于 120-140 m。至少三个主要 Melt-Water-Pulse (MWP ) 事件(19ka-MWP， MWP-1A 和 MWP-1B ) 为最后冰川的消失是可认识的，哪个持续从的 MWP-1A 事件类似于 14.2 到类似于 13.7 ka B.P 具有大多数意义。然而，精确预定和可争辩、争论的 MWP-1A 事件遗体的来源。融化流进诺思大西洋的最后冰川的消失的水，这长被要求了导致了减速或甚至一随后影响了全球气候的 thermohaline 发行量(THC ) 的 shutdown 变化。因此，这争论的焦点在建立在 MWP 事件和突然的气候变化之间的一种合理关系在于。这里，我们总结许多地质并且最后冰川的消失的模型结果，得出主要 MWP 事件没与严密 stadials 相应，也不总是发生在气候颠倒间隔以内的一个结论。最后冰川的消失的 MWP 事件在 THC 的紧张上有很弱的影响并且不能触发全球气候的倒塌。我们需要重新估计影响时间在全球气候系统上融化水可变性。

关键词：冰川退缩 MWP 温盐循环气候剧变

Modeling and analysis for material removal and surface roughness in fluid jet polishing of optical glass

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Friction 2024年第7期12卷 1548-1563页

作者： Zhongchen CAO Ming WANG Haitao LIU tian huang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300072China School of Engineering The University of WarwickCoventry CV47ALUK

luid jet polishing(FJP)is a non-contact polishing technology that can fabricate free-form optical surfaces with sub-micron-level form accuracy and nano-level surface roughness,especially for hard and brittle *** surface generation model of FJP can be used to guide the determination and optimization of process parameters and is of great significance for understanding the evolution mechanism of surface ***,predictive models for the microscopic topography of polished surfaces are still *** study established a macroscopic surface profile model for predicting 3D material removal characteristics and surface texture by combining the 3D computer fluid dynamics(CFD)simulation model and single-particle erosion mechanism.A fractal theory-based erosion model has been built to calculate the material removal caused by the erosion of a single abrasive particle on the rough surface;thus,it predicts the micro-topography and surface roughness of the polished samples.A series of polishing experiments were conducted to analyze the feasibility and accuracy of the model quantitatively and study the influence mechanism of process parameters on the material removal characteristics and surface *** indicated that the models could well predict material removal and surface *** prediction accuracy of the surface roughness Ra and maximum removal depth is better than 91.6%and 90%,*** is also found that the material removal rate of FJP could reach 0.517 mm3/min,and the surface roughness convergence rate could reach 62.9%.

关键词： fluid jet polishing(FJP) computational fluid dynamics(CFD) material removal mechanism surface roughness theoretical model

Observability and estimability of passive radar with unknown illuminator states using different observations

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1193-1205页

作者： JING Tong tian Wei huang Gaoming PENG Huafu College of Electronic Engineering Naval University of EngineeringWuhan 430033China

Most existing studies about passive radar systems are based on the already known illuminator of opportunity(IO)***,in practice,the receiver generally has little knowledge about the IO *** research has studied this *** paper analyzes the observability and estimability for passive radar systems with unknown IO states under three typical ***,the directions of high and low estimability with respect to various states are ***,two types of observations are taken into *** effects of different observations on both observability and estimability are well *** the observability test,linear and nonlinear methods are considered,which proves that both tests are applicable to the *** simulations confirm the correctness of the theoretical analysis.

关键词： passive radar passive coherent location(PCL) observability estimability unknown illuminator states

Osteoporotic Vertebral Fracture Classification in X-rays Based on a Multi-modal Semantic Consistency Network

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Journal of Bionic Engineering 2022年第6期19卷 1816-1829页

作者： Yuzhao Wang tian Bai Tong Li Lan huang College of Computer Science and Technology Jilin UniversityChangchun130012China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin UniversityChangchun130012China Department of Orthopedics The Second Hospital of Jilin UniversityChangchun130012China

Osteoporotic Vertebral Fracture(OVFs)is a common lumbar spine disorder that severely affects the health of *** a clear bone blocks boundary,CT images have gained obvious advantages in OVFs *** with CT images,X-rays are faster and more inexpensive but often leads to misdiagnosis and miss-diagnosis because of the overlapping *** how to transfer CT imaging advantages to achieve OVFs classification in X-rays is *** this purpose,we propose a multi-modal semantic consistency network which could do well X-ray OVFs classification by transferring CT semantic consistency *** from existing methods,we introduce a feature-level mix-up module to get the domain soft labels which helps the network reduce the domain offsets between CT and *** the meanwhile,the network uses a self-rotation pretext task on both CT and X-ray domains to enhance learning the high-level semantic invariant *** employ five evaluation metrics to compare the proposed method with the state-of-the-art *** final results show that our method improves the best value of AUC from 86.32 to 92.16%.The results indicate that multi-modal semantic consistency method could use CT imaging features to improve osteoporotic vertebral fracture classification in X-rays effectively.

关键词： Osteoporotic vertebral fracture classification Cross-modality Unsupervised domain adaptation Transfer learning Convolutional neural network Computer-aided diagnosis

Residual Vibration Reduction of High-Speed Pick-and-Place Parallel Robot Using Input Shaping

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Chinese Journal of Mechanical Engineering 2022年第1期35卷 62-69页

作者： Xianlei Shan Yuhang Li Haitao Liu tian huang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300354China School of Engineering The University of WarwickCoventry CV47ALUK.

Because of their elastic links and joints,high-speed parallel robots for pick-and-place operations inevitably suffer from residual vibrations that significantly degrade their positioning *** effective approach based on the input shaping technique is presented in this paper for suppressing the residual vibration in these parallel *** addressing the design principle of an input shaper for a parallel robot with flexible actuated joints,a robust optimal input shaper is developed by considering the configuration-dependent flexible modes and minimizing the maximum percentage of residual vibration at the *** input shaper allows a good overall performance to be achieved throughout the entire *** results on a 4-DOF SCARA-type parallel robot show that the residual vibration of the end-effector is dramatically reduced and the dynamic positioning accuracy of the robot significantly improved.

关键词： Pick-and-place parallel robot Residual vibration reduction Input shaping

Base placement optimization of a mobile hybrid machining robot by stiffness analysis considering reachability and nonsingularity constraints

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Chinese Journal of Aeronautics 2023年第11期36卷 398-416页

作者： Zhongyang ZHANG Juliang XIAO Haitao LIU tian huang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300340China School of Engineering The University of WarwickCoventry CV47ALUK

The mobile hybrid machining robot has a very bright application prospect in the field of high-efficiency and high-precision machining of large aerospace ***,an inappropriate base placement may make the robot encounter a singular configuration,or even fail to complete the entire machining task due to *** addition to considering the two constraints of reachability and non-singularity,this paper also optimizes the robot base placement with stiffness as the goal to improve the machining *** of all,starting from the structure of the robot,the reachability and nonsingularity constraints are transformed into a simple geometric constraint imposed on the base placement:feasible base placement ***,genetic algorithm is used to search for the base placement with near optimal stiffness(near optimal base placement for short)in the feasible base placement ***,multiple controlled experiments were carried out by taking the milling of a protuberance on the spacecraft cabin as an *** is found that the calculated optimal base placement meets all the constraints and that the machining quality was indeed *** addition,compared with simple genetic algorithm,it is proved that the feasible base placement area method can shorten the running time of the whole program.

关键词： Aerospace industry Base placement optimization Hybrid machining robot Mobile robot Robot application Singularity avoidance Stiffness optimization