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Parametric Optimization of Wheel Spoke Structure for Drag Reduction of an Ahmed Body

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 955-975页

作者： huihui Zhai Dongqi Jiao Haichao zhou Institute of Electrical and Information Engineering Zhenjiang CollegeZhenjiang212028China School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang212013China

The wheels have a considerable influence on the aerodynamic properties and can contribute up to 25%of the total drag on modern vehicles.In this study,the effect of the wheel spoke structure on the aerodynamic performance of the isolated wheel is investigated.Subsequently,the 35°Ahmed body with an optimized spoke structure is used to analyze the flow behavior and the mechanism of drag reduction.The Fluent software is employed for this investigation,with an inlet velocity of 40 m/s.The accuracy of the numerical study is validated by comparing it with experimental results obtained from the classical Ahmed model.To gain a clearer understanding of the effects of the wheel spoke parameters on the aerodynamics of both the wheel and Ahmedmodel,and five design variables are proposed:the fillet angleα,the inside arc radius R1,the outside radius R2,and the same length of the chord L1 and L2.These variables characterize the wheel spoke structure.The Optimal Latin Hypercube designmethod is utilized to conduct the experimental design.Based on the simulation results of various wheel spoke designs,the Kriging model and the adaptive simulated annealing algorithm is selected to optimize the design parameters.The objective is to achieve the best combination for maximum drag reduction.It is indicated that the optimized spoke structure resulted in amaximum drag reduction of 5.7%and 4.7%for the drag coefficient of the isolated wheel and Ahmed body,respectively.The drag reduction is primarily attributed to changes in the flow state around the wheel,which suppressed separation bubbles.Additionally,it influenced the boundary layer thickness around the car body and reduced the turbulent kinetic energy in the wake flow.These effects collectively contributed to the observed drag reduction.

关键词： Ahmed body wheel spoke design parameter optimization drag reduction numerical simulation

Study on Coded Permutation Entropy of Finite Length Gaussian White Noise Time Series

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Chinese Journal of Electronics 2024年第1期33卷 185-194页

作者： huihui SUN Xiaofeng ZHANG School of Physics and Information Technology Shaanxi Normal University

As an extension of permutation entropy(PE), coded permutation entropy(CPE) improves the performance of PE by making a secondary division for ordinal patterns defined in PE. In this study, we provide an exploration of the statistical properties of CPE using a finite length Gaussian white noise time series theoretically. By means of the Taylor series expansion, the approximate expressions of the expected value and variance of CPE are deduced and the Cramér-Rao low bound(CRLB) is obtained to evaluate the performance of the CPE estimator. The results indicate that CPE is a biased estimator, but the bias only depends on relevant parameters of CPE and it can be easily corrected for an arbitrary time series. The variance of CPE is related to the encoding patterns distribution,and the value converges to the CRLB of the CPE estimator when the time series length is large enough. For a finitelength Gaussian white noise time series model, the predicted values can match well with the actual values, which further validates the statistic theory of CPE. Using the theoretical expressions of CPE, it is possible to better understand the behavior of CPE for most of the time series.

关键词： Coded permutation entropy Gaussian white noise Finite-length time series Cramér-Rao low bound

Evaluating quality of motion for unsupervised video object segmentation

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Optoelectronics Letters 2024年第6期20卷 379-384页

作者： CHENG Guanjun SONG huihui Jiangsu Key Laboratory of Big Data Analysis Technology Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment TechnologyNanjing University of Information Science&TechnologyNanjing 210044China12

Current mainstream unsupervised video object segmentation(UVOS) approaches typically incorporate optical flow as motion information to locate the primary objects in coherent video frames. However, they fuse appearance and motion information without evaluating the quality of the optical flow. When poor-quality optical flow is used for the interaction with the appearance information, it introduces significant noise and leads to a decline in overall performance. To alleviate this issue, we first employ a quality evaluation module(QEM) to evaluate the optical flow. Then, we select high-quality optical flow as motion cues to fuse with the appearance information, which can prevent poor-quality optical flow from diverting the network's attention. Moreover, we design an appearance-guided fusion module(AGFM) to better integrate appearance and motion information. Extensive experiments on several widely utilized datasets, including DAVIS-16, FBMS-59, and You Tube-Objects, demonstrate that the proposed method outperforms existing methods.

关键词： Evaluating quality of motion for unsupervised video object segmentation

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Tumor microenvironment reprogramming by nanomedicine to enhance the effect of tumor immunotherapy

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Asian Journal of Pharmaceutical Sciences 2024年第2期19卷 1-37页

作者： Yu Huang Hui Fan huihui Ti School of Chinese Materia Medica Guangdong Pharmaceutical UniversityGuangzhou 510006China Guangdong Province Precise Medicine Big Date of Traditional Chinese Medicine Engineering Technology Research Center Guangdong Pharmaceutical UniversityGuangzhou 510006China School of Pharmacy Guangdong Pharmaceutical UniversityGuangzhou 510006China

With the rapid development of the fields of tumor biology and immunology, tumor immunotherapy has been used in clinical practice and has demonstrated significant therapeutic potential, particularly for treating tumors that do not respond to standard treatment options. Despite its advances, immunotherapy still has limitations, such as poor clinical response rates and differences in individual patient responses, largely because tumor tissues have strong immunosuppressive microenvironments. Many tumors have a tumor microenvironment (TME) that is characterized by hypoxia, low pH, and substantial numbers of immunosuppressive cells, and these are the main factors limiting the efficacy of antitumor immunotherapy. The TME is crucial to the occurrence, growth, and metastasis of tumors. Therefore, numerous studies have been devoted to improving the effects of immunotherapy by remodeling the TME. Effective regulation of the TME and reversal of immunosuppressive conditions are effective strategies for improving tumor immunotherapy. The use of multidrug combinations to improve the TME is an efficient way to enhance antitumor immune efficacy. However, the inability to effectively target drugs decreases therapeutic effects and causes toxic side effects. Nanodrug delivery carriers have the advantageous ability to enhance drug bioavailability and improve drug targeting. Importantly, they can also regulate the TME and deliver large or small therapeutic molecules to decrease the inhibitory effect of the TME on immune cells. Therefore, nanomedicine has great potential for reprogramming immunosuppressive microenvironments and represents a new immunotherapeutic strategy. Therefore, this article reviews strategies for improving the TME and summarizes research on synergistic nanomedicine approaches that enhance the efficacy of tumor immunotherapy.

关键词： Tumor immunotherapy Tumor micr oenvir onment Nanomedicine Tumor repr ogramming

Modulation of Neuronal Activity and Saccades at Theta Rhythm During Visual Search in Non-human Primates

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Neuroscience Bulletin 2022年第10期38卷 1183-1198页

作者： Jin Xie Ting Yan Jie Zhang Zhengyu Ma huihui zhou The Brain Cognition and Brain Disease Institute Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research InstitutionsShenzhen518055China University of Chinese Academy of Sciences Beijing100049China The Research Center for Artificial Intelligence Peng Cheng LaboratoryShenzhen518000China

Active exploratory behaviors have often been associated with theta oscillations in rodents,while theta oscillations during active exploration in non-human primates are still not well understood.We recorded neural activities in the frontal eye field(FEF)and V4 simultaneously when monkeys performed a free-gaze visual search task.Saccades were strongly phase-locked to theta oscillations of V4 and FEF local field potentials,and the phase-locking was dependent on saccade direction.The spiking probability of V4 and FEF units was significantly modulated by the theta phase in addition to the time-locked modulation associated with the evoked response.V4 and FEF units showed significantly stronger responses following saccades initiated at their preferred phases.Granger causality and ridge regression analysis showed modulatory effects of theta oscillations on saccade timing.Together,our study suggests phase-locking of saccades to the theta modulation of neural activity in visual and oculomotor cortical areas,in addition to the theta phase locking caused by saccade-triggered responses.

关键词： Visual search Saccade Theta rhythm FEF V4 Non-human primate

Product quality prediction based on RBF optimized by firefly algorithm

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Journal of Systems Engineering and Electronics 2024年第1期35卷 105-117页

作者： HAN huihui WANG Jian CHEN Sen YAN Manting College of Electronics and Information Engineering Tongji UniversityShanghai 201804China

With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality prediction models have many disadvantages,such as high complexity and low accuracy.To overcome the above problems,we propose an optimized data equalization method to pre-process dataset and design a simple but effective product quality prediction model:radial basis function model optimized by the firefly algorithm with Levy flight mechanism(RBFFALM).First,the new data equalization method is introduced to pre-process the dataset,which reduces the dimension of the data,removes redundant features,and improves the data distribution.Then the RBFFALFM is used to predict product quality.Comprehensive expe riments conducted on real-world product quality datasets validate that the new model RBFFALFM combining with the new data pre-processing method outperforms other previous me thods on predicting product quality.

关键词： product quality prediction data pre-processing radial basis function swarm intelligence optimization algorithm

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Design,Hydrodynamic Analysis,and Testing of a Bio-inspired Movable Bow Mechanism for the Hybrid-driven Underwater Glider

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Journal of Bionic Engineering 2023年第4期20卷 1493-1513页

作者： Yanhui Wang Yudong Guo Shaoqiong Yang Tongshuai Sun Xi Wang huihui zhou Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin300072China The Joint Laboratory of Ocean Observing and Detection Laoshan LaboratoryQingdao266237China

Hybrid-driven Underwater Glider(HUG)is a new type of underwater vehicle which integrates the functions of an Autonomous Underwater Glider(AUG)and an Autonomous Unmanned Vehicle(AUV).Although HUG has the characteristics of long endurance distance,its maneuverability still has room to be improved.This work introduces a new movement form of the neck of the underwater creature into HUG and proposes a parallel mechanism to adjust the attitude angle and displacement of the HUG’s bow,which can improve the steering maneuverability.Firstly,the influence of bow movement and rotation on the hydrodynamic force and flow field of the whole machine is analyzed by using the Computational Fluid Dynamics(CFD)method.The degree of freedom,attitude control range and movement amount of the Movable Bow Mechanism(MBM)are obtained,and then the design of MBM is completed based on these constraints.Secondly,the kinematic and dynamic models of MBM are established based on the closed vector method and the Lagrange equation,respectively,which are fully verified by comparing the results of simulation in Matlab and Adams software,then a Radial Basis Function(RBF)neural network adaptive sliding mode controller is designed to improve the dynamic response effect of the output parameters of MBM.Finally,a prototype of MBM is manufactured and assembled.The kinematic,dynamics model and controller are verified by experiments,which provides a basis for applying MBM in HUGs.

关键词： Underwater glider Movable bow mechanism Hydrodynamic simulation Steering maneuverability

High success rate of fiberscope-monitored intubation via a supraglottic airway device BlockBusterTMin good device positioning: A prospective observational study

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中华医学杂志(英文版) 2024年第7期137卷 871-873页

作者： Hu Zhenfa Su Kai Miao huihui Gao Xue Xue Fushan Tian Ming Department of Anesthesiology Beijing Friendship Hospital Capital Medical University Beijing 100050 China Beijing Shijitan Hospital Beijing 100038

Smart Breeding Platform:A web-based tool for high-throughput population genetics,phenomics,and genomic selection

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Molecular Plant 2024年第5期17卷 677-681页

作者： huihui Li Xin Li Peng Zhang Yingwei Feng Junri Mi Shang Gao Lele Sheng Mohsin Ali Zikun Yang Liang Li Wei Fang Wensheng Wang Qian Qian Fei Gu Wenbin zhou State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural Sciences(CAAS)Beijing 100081China Nanfan Research Institute CAASSanyaHainan 572024China DAMO Academy Alibaba GroupHangzhou 310023China Hupan Lab Hangzhou 310023China Yazhouwan National Laboratory No.8 Huanjin RoadYazhou DistrictSanya CityHainan Province 572024China State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhouZhejiang 310006China

Dear Editor,In the era of big data and artificial intelligence,"smart breeding"has become a broad conceptual framework encompassing the paradigm shift of crop breeding to relying on analysis of high-throughput population genetics and phenomics data to conduct genomic selection,allowing identification and optimal use of the genetic potential in crop species(Xiao et al.,2022;Xu et al.,2022;Wang et al.,2023).Most existing tools for analyzing high-throughput breeding data require extensive computational power,complex installation processes,and command-line expertise and are therefore challenging and inconvenient for the majority of researchers and breeders(Brandies and Hogg,2021).

关键词： breeding artificial breed