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Journal of Environmental Sciences 2023年第7期129卷 79-89页

作者： Yong He Xiangyu Wang Zhaobin Zhang College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

Sediment core is the recorder of polycyclic aromatic hydrocarbon(PAH)pollutions and the associated sedimentary organic matter(SOM),acting as crucial supports for pollution control and environmental management.here,the sedimentary records of PAHs and SOM in the past century in Lake Taihu,China,were reconstructed from a 50-cm sediment core.On the one hand,the presence of PAHs ranged from 8.99 to 199.2 ng/g.Vertically,PAHs declined with the depth increased,and the sedimentation history of PAHswas divided into two stages with a discontinuity at 20 cm depth.In composition,PAHs in the sediment core were dominated by three-ring PAHs(44.6%±9.1%,mean±standard deviation),and were followed by four-ring(27.0%±3.3%),and five-ring(12.1%±4.0%)PAHs.In toxicity assessment,the sedimentary records of benzo[a]pyrene-based toxic equivalency were well described by an exponential model with R-square of 0.95,and the environmental background toxic value was identified as 1.62 ng/g.On the other hand,different components of SOM were successfully identified by n-alkanemarkers(phe variations of SOMwerewell explained(84.6%).A discontinuity of SOM was recognized at 22 cm depth.Association study showed that the sedimentary PAHs were associated with both anthropogenic and biogenic SOM(phe vertical distributions of PAHs were driven by sedimentary SOM.Therefore,environmental processes such as biogenic factors should attract more attentions as well as PAH emissions to reduce the impacts of PAHs.

关键词： Polycyclic aromatic hydrocarbons (PAHs) N-alkanes Sedimentary records Composition Toxicity assessment Lake Taihu

Balancing the customization and standardization:exploration and layout surrounding the regulation of the growing field of 3D-printed medical devices in China

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Bio-Design and Manufacturing 2022年第3期5卷 580-606页

作者： Zhongboyu Jin Chaofan he Jianzhong Fu Qianqian Han Yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of Materials Processing and Mold Zhengzhou UniversityZhengzhou 450002China Cancer Center Zhejiang UniversityHangzhou 310058China National Institutes for Food and Drug Control Beijing 102629China

Medical devices are instruments and other tools that act on the human body to aid clinical diagnosis and disease treatment,playing an indispensable role in modern medicine.Nowadays,the increasing demand for personalized medical devices poses a significant challenge to traditional manufacturing methods.The emerging manufacturing technology of three-dimensional(3D)printing as an alternative has shown exciting applications in the medical field and is an ideal method for manufacturing such personalized medical devices with complex structures.However,the application of this new technology has also brought new risks to medical devices,making 3D-printed devices face severe challenges due to insufficient regulation and the lack of standards to provide guidance to the industry.This review aims to summarize the current regulatory landscape and existing research on the standardization of 3D-printed medical devices in China,and provide ideas to address these challenges.We focus on the aspects concerned by the regulatory authorities in 3D-printed medical devices,highlighting the quality system of such devices,and discuss the guidelines that manufacturers should follow,as well as the current limitations and the feasible path of regulation and standardization work based on this perspective.The key points of the whole process quality control,performance evaluation methods and the concept of whole life cycle management of 3D-printed medical devices are emphasized.Furthermore,the significance of regulation and standardization is pointed out.Finally,aspects worthy of attention and future perspectives in this field are discussed.

关键词： 3D printing Medical device Regulation Standardization

Biomanufacturing: from biomedicine to biomedicine

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Bio-Design and Manufacturing 2021年第4期4卷 912-913页

作者： Yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China

Recently,the First Youth Forum of Bio-design&Manufac-turing(BDM)was held in Hangzhou on July 3,2021.Acad-emician Huayong Yang,Editor-in-Chief of BDM,acted as the Chairman and this conference was jointly sponsored by the School of Mechanical Engineering,Zhejiang Univer-sity,as well as the State Key Laboratory of Fluid Power and Mechatronic Systems.A total of 11 prestigious pro-fessors and researchers from all over the world presented at the conference either online or offline,while more than 150 researchers and students from different universities and research institutes attended and heatedly discussed their research in the fields of bio-design and manufacturing from various perspectives.

关键词： while jointly heated

Field estimation of maize plant height at jointing stage using an RGB-D camera

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The Crop Journal 2022年第5期10卷 1274-1283页

作者： Ruicheng Qiu Man Zhang Yong He College of Biosystem Engineering and Food Science Zhejiang UniversityHangzhou 310058ZhejiangChina Key Laboratory of Modern Precision Agriculture System Integration Research Ministry of EducationChina Agricultural UniversityBeijing 100083China

Plant height can be used for assessing plant vigor and predicting biomass and yield. Manual measurement of plant height is time-consuming and labor-intensive. We describe a method for measuring maize plant height using an RGB-D camera that captures a color image and depth information of plants under field conditions. The color image was first processed to locate its central area using the S component in HSV color space and the Density-Based Spatial Clustering of Applications with Noise algorithm. Testing showed that the central areas of plants could be accurately located. The point cloud data were then clustered and the plant was extracted based on the located central area. The point cloud data were further processed to generate skeletons, whose end points were detected and used to extract the highest points of the central leaves. Finally, the height differences between the ground and the highest points of the central leaves were calculated to determine plant heights. The coefficients of determination for plant heights manually measured and estimated by the proposed approach were all greater than 0.95. The method can effectively extract the plant from overlapping leaves and estimate its plant height. The proposed method may facilitate maize height measurement and monitoring under field conditions.

关键词： Maize plant heigh Kinect Maize central area Point cloud data Image processing

Autonomous mission reconstruction during the ascending flight of launch vehicles under typical propulsion system failures

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Chinese Journal of Aeronautics 2022年第6期35卷 211-225页

作者： Zhengyu SONG Yin LIU Yong He Cong WANG China Academy of Launch Vehicle Technology Beijing 100076China Beijing Institute of Astronautical Systems Engineering Beijing 100076China Beijing Aerospace Automatic Control Institute Beijing 100854China

In recent years, Chinese Long March(LM) launchers have experienced several launch failures, most of which occurred in their propulsion systems, and this paper studies Autonomous Mission Reconstruction(AMRC) technology to alleviate losses due to these failures. The status of the techniques related to AMRC, including trajectory and mission planning, guidance methods,and fault tolerant technologies, are reviewed, and their features are compared, which reflect the challenges faced by AMRC technology. After a brief introduction about the failure modes of engines that can occur during flight, and the fundamentals of trajectory planning and joint optimization of the target orbit and flight path, an AMRC algorithm is proposed for geostationary transfer orbit launch missions. The algorithm evaluates the residual performance onboard, and plans new objectives and corresponding flight path by iterative guidance mode or segmented state triggered optimization methods in real-time. Three failure scenarios that have occurred during previous LM missions are simulated to check the robustness of the algorithm: imminent explosion risk of the boosters’ engines, thrust drop during the first stage of flight, and being unable to start the engine during the second stage. The payloads would fall from space according to the current design under these conditions, but they were saved with the AMRC algorithm in the simulations, which allowed the rocket to get into the target orbit as intended or the payloads were deployed in other orbits without crashing. Although spaceflight can be very unforgiving, the AMRC algorithm has the potential to avoid the total loss of a launch mission when faced with these kinds of typical failures.

关键词： Autonomous mission reconstruction Closed-loop guidance State triggered indices Rescue orbits Launch vehicles

Projection-based 3D bioprinting for hydrogel scaffold manufacturing

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Bio-Design and Manufacturing 2022年第3期5卷 633-639页

作者： Yuan Sun Kang Yu Qing Gao Yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Engineering for Life Group(EFL) Suzhou 215101China Key Laboratory of Materials Processing and Mold Zhengzhou UniversityZhengzhou 450002China Cancer Center Zhejiang UniversityHangzhou 310058China

Projection-based 3D bioprinting(PBP):a powerful method to fabricate 3D cellular structures Three-dimensional(3D)bioprinting has played an important role in tissue engineering and regenerative medicine areas over the past decade[1].Different from traditional cell cultures in Petri dishes,3D bioprinting can build bionic structures with a better potential to become artificial organ substitutes[2–4].With the development of photocurable biomaterials,the projection-based 3D printing method has been successfully applied in biological research[5,6].

关键词： printing biomaterials projection

Investigation of the shock compression behaviors of Al/PTFE composites with experimental and a 3D mesoscale-model

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Defence Technology（防务技术） 2022年第1期18卷 62-71页

作者： Xiang-li Yang Yong He Yuan he Chuan-ting Wang Jie Zhou Departnentsof Mecharical Engneering Nanjing Uriversity of Science&Technology NanjingJiangsu210094PR China Hubei Aeros pace Flight Vehide Institute Wuhan 430040PR China

The responses of Al/PTIFE reactive materials(RMs)under shock compression were investigated by a single-stage gas gun.A 3D mesoscale-model was established based on micro-computed tomography(micro-CT)slice images and confirmed with experimental results.In the high-pressure stage,the com-posites reacted partially,whereas there were no deviations between the partially reacted Hugoniot and the inert simulation results.The simulation reveals that the Teflon matrix melting on the high shock pressure.Melts and decomposition of the PTFE accelerated the diffusion of the atoms.Thus,the reactions of the Al/PTFE composites are more like a combustion rather than a detonation.

关键词： AI/PTFE reactive materials 3D mesoscale-model Shock-assisted reaction Shock Hugoniot

Application of LSTM model optimized by individual-ordering- basedadaptivegeneticalgorithmin stock forecasting

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International Journal of Intelligent Computing and Cybernetics 2023年第2期16卷 277-294页

作者： Yong He Xiaohua Zeng Huan Li Wenhong Wei School of Computer Dongguan University of TechnologyDongguanChina School of Economics and Trade Guangzhou Xinhua UniversityDongguanChina

Purpose-To improve the accuracy of stock price trend prediction in the field of quantitative financial trading,this paper takes the prediction accuracy as the goal and avoid the enormous number of network structures and hyperparameter adjustments of long-short-term memory(LSTM).Design/methodology/approach-In this paper,an adaptive genetic algorithm based on individual ordering is used to optimize the network structure and hyperparameters of the LSTM neural network automatically.Findings-The simulation results show that the accuracy of the rise and fall of the stock outperform than the model with LSTM only as well as other machine learning models.Furthermore,the efficiency of parameter adjustment is greatly higher than other hyperparameter optimization methods.Originality/value-(1)The AGA-LSTM algorithm is used to input various hyperparameter combinations into genetic algorithm to find the best hyperparameter combination.Compared with other models,it has higher accuracy in predicting the up and down trend of stock prices in the next day.(2)Adopting real coding,elitist preservation and self-adaptive adjustment of crossover and mutation probability based on individual ordering in the part of genetic algorithm,the algorithm is computationally efficient and the results are more likely to converge to the global optimum.

关键词： Stock price prediction Long-short-term memory Adaptive genetic algorithm Machine learning

Anoctamin 4 defines glucose-inhibited neurons in the ventromedial hypothalamus

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Neural Regeneration Research 2024年第6期19卷 1177-1178页

作者： Longlong Tu Yanlin he yong Xu Children's Nutrition Research Center Department of Pediatrics Baylor College of Medicine Department of Molecular and Cellular Biology Section of Endocrinology Diabetes and Metabolism Department of Medicine Baylor College of Medicine Brain Glycemic and Metabolism Control Department Pennington Biomedical Research Center Louisiana State University

Glucose is the primary fuel source of the brain,and therefore glucose levels need to be tightly regulated and maintained within a small physiological range.Certainly,the body necessitates a stable supply of energy mainly provided by glucose for various bodily functions.High or low blood glucose levels would impair the physiological functions of various organs of the body.Prolonged high blood glucose(i.e.,

关键词： HYPOGLYCEMIA

Effects of temperature and particle size on the thermophysical properties of six plant-origin protein supplements

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International Journal of Agricultural and Biological Engineering 2023年第6期16卷 263-272页

作者： Dandan Kong Jiyuan Chen Hongying Wang Yong He College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058China Key Laboratory of Spectroscopy Sensing Ministry of Agriculture and Rural AffairsHangzhou 310058China College of Engineering China Agricultural UniversityBeijing 100083China

Reasonable design of the parameters of thermal processing such as conditioning and cooling according to formula changes of pelleted feeds has always been a serious challenge for Chinese feed mills and feed equipment manufacturers. Studying the thermophysical properties of different protein feeds under different temperatures and particle sizes will facilitate the equipment design, parameter optimization, and simulation for the thermal processing of pelleted feeds. In this study, the specific heat (Cp), thermal conductivity (kb), and thermal diffusivity (α) of six plant protein supplements with three particle sizes were determined over a temperature range of 25℃-100℃. The differences in Cp, kb, and α among different feedstuffs and particle sizes were analyzed and the influences of temperature and particle size on these properties were evaluated. Results showed that the Cp, kb, and α of all the feedstuffs increased with increasing temperature and varied from 1.622 to 2.417 kJ/(kg∙℃), 0.080 to 0.362 W/(m∙℃), 6.379×10^(-8) to 21.984×10^(-8) m^(2)/s, respectively. To rise to the same temperature, the distiller’s dried grain with solubles (DDGS) needed to absorb 3% more heat than that required for soybean meal (SBM), while the rest four feedstuffs just needed to absorb 93%-98% heat for SBM. Particle size had no significant effect on Cp for all the feedstuffs (p>0.05). However, descending trends in kb and α were observed with increasing particle size for a certain feedstuff at the same bulk density. In addition, regression equations with only statistically significant terms were developed to describe Cp, kb, and α as a function of temperature and particle size for six feedstuffs. The results can provide basic theory and data for the optimization of thermal processing parameters required for the plant-protein ingredient change in compound feed formulations.

关键词： plant protein supplement specific heat thermal conductivity thermal diffusivity particle size