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Journal of Oceanology and limnology 2024年第1期42卷 174-186页

作者： Yufei ZHANG Xianjun li Yuhui li Shiqi liU Yanrui chen Miao JIA xin WANG Lu ZHANG Qiping GAO liang ZHANG Daoyong YU Baosheng GE State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology China University of Petroleum(East China)Qingdao 266580China Tongwei Co. Ltd.Healthy Aquaculture Key Laboratory of Sichuan ProvinceChengdu 610093China

light plays an important role in the photosynthesis and metabolic process of ***,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly *** this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically *** different colored lights,*** all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light *** the same light intensity,different colored lights show different growth rate of *** following the sequence of red>white>green>yellow>*** maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red *** energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>*** analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism *** study provides a conducive and efficient way to promote biomass production and protein accumulation of *** by regulating light conditions.

关键词： microalgae light emitting diode protein accumulation biomass production transcriptomic analysis

Perspective of Calcium Imaging Technology Applied to Acupuncture Research

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Chinese Journal of Integrative Medicine 2024年第1期30卷 3-9页

作者： li Sha liU Yun ZHANG Nan li Wang XU Wen-jie XU Yi-qian chen Yi-yuan CUI Xiang ZHU Bing GAO xin-yan Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing(100700)China

Acupuncture, a therapeutic treatment defined as the insertion of needles into the body at specific points(ie, acupoints), has growing in popularity world-wide to treat various diseases effectively, especially acute and chronic pain. In parallel, interest in the physiological mechanisms underlying acupuncture analgesia, particularly the neural mechanisms have been increasing. Over the past decades, our understanding of how the central nervous system and peripheral nervous system process signals induced by acupuncture has developed rapidly by using electrophysiological methods. However, with the development of neuroscience, electrophysiology is being challenged by calcium imaging in view field, neuron population and visualization in vivo. Owing to the outstanding spatial resolution, the novel imaging approaches provide opportunities to enrich our knowledge about the neurophysiological mechanisms of acupuncture analgesia at subcellular, cellular, and circuit levels in combination with new labeling, genetic and circuit tracing techniques. Therefore, this review will introduce the principle and the method of calcium imaging applied to acupuncture research. We will also review the current findings in pain research using calcium imaging from in vitro to in vivo experiments and discuss the potential methodological considerations in studying acupuncture analgesia.

关键词： acupuncture research calcium imaging optical imaging nervous system

太赫兹光谱在转基因菜籽油鉴别中的应用:基于改进蜉蝣算法的支持向量机模型

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物理学报 2024年第5期73卷 360-368页

作者：陈涛李欣桂林电子科技大学电子工程与自动化学院桂林541004

为实现对转基因和非转基因菜籽油的快速准确鉴别,结合太赫兹时域光谱技术,提出了一种基于改进蜉蝣优化算法的支持向量机模型.以两种转基因和两种非转基因菜籽油为研究对象,应用太赫兹时域光谱技术获取其光谱信息,发现相比于非转基因菜籽... 详细信息

为实现对转基因和非转基因菜籽油的快速准确鉴别,结合太赫兹时域光谱技术,提出了一种基于改进蜉蝣优化算法的支持向量机模型.以两种转基因和两种非转基因菜籽油为研究对象,应用太赫兹时域光谱技术获取其光谱信息,发现相比于非转基因菜籽油,转基因菜籽油在太赫兹波段具有更强的吸收特性,同时它们的吸收光谱极为相似,难以通过观察法进行准确区分.为此,提出一种基于改进蜉蝣优化算法的支持向量机模型,通过采用蜉蝣优化算法对支持向量机参数进行寻优,并引入自适应惯性权重和Lévy飞行两种策略改进蜉蝣优化算法在寻优过程容易陷入局部最优解的问题,增强蜉蝣优化算法的全局搜索能力和稳健性.实验结果表明:改进后的蜉蝣优化算法能够更有效地寻找到支持向量机的最优参数组合,提升鉴别模型的整体性能,该模型对4种菜籽油的识别精度为100%.因此,本研究为转基因菜籽油的类型鉴别提供了一种快速有效的新方法,也为其他转基因物质的鉴别提供了有价值的参考.

关键词：转基因菜籽油太赫兹光谱分类鉴别蜉蝣优化算法

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Research progress on the water vapor channel within the Yarlung Zsangbo Grand Canyon, China

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Atmospheric and Oceanic Science Letters 2024年第5期17卷 10-15页

作者： Xuelong chen Yajing liu Yaoming Ma Xiangde Xu xin Xu Luhan li Dianbin Cao Qiang Zhang Gaili Wang Maoshan li Siqiong Luo xin Wang Land–Atmosphere Interaction and its Climatic Effects Group State Key Laboratory of Tibetan Plateau Earth SystemEnvironment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijingChina State Key Laboratory of Disastrous Weather China Academy of Meteorological SciencesBeijingChina The Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina College of Atmospheric Sciences Plateau Atmosphere and Environment Key Laboratory of Sichuan ProvinceChengdu University of Information TechnologyChengduChina

The Second Tibetan Plateau Scientific Expedition and Research Program tasked a research team with the“Investigation of the water vapor channel of the Yarlung Zsangbo Grand Canyon(INVC)”in the southeastern Tibetan Plateau(TP).This paper summarizes the scientific achievements obtained from the data collected by the INVC observation network and highlights the progress in investigating the development of heavy rainfall events associated with water vapor *** rain gauge network of the INVC can represent the impacts of the Yarlung Zsangbo Grand Canyon(YGC)topography on precipitation at the hourly *** microphysical characteristics of the precipitation in the YGC are different than those in the lowland *** GPM-IMERG(Integrated MultisatellitE Retrievals for Global Precipitation Measurement)satellite precipitation data for the YGC region should be calibrated before they are *** meridional water vapor flux through the YGC is more important than the zonal flux for the precipitation over the southeastern *** decreased precipitation around the YGC region is partly due to the decreased meridional water vapor flux passing through the ***-resolution numerical models can benefit precipitation forecasting in this region by using a combination of specific schemes that capture the valley wind and water vapor flux along the valley floor.

关键词： Water vapor channel Land-air interaction Mountian meteorology Extreme rainfall Observation network

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中子输运计算界面流方法的数学共扼方程

核动力工程 2005年第2期26卷 97-101页

作者：张颖陈伟陈立新西北核技术研究所西安710024

以子区内中子源为常源近似条件下的中子积分输运方程为前向方程,推导了中子积分输运方程界面流算法在六角形几何情况下的数学共扼方程;介绍了该数学共扼方程求解的内、外迭代策略,并对前向方程计算程序TPHEX进行了改造,得到了常源近似... 详细信息

以子区内中子源为常源近似条件下的中子积分输运方程为前向方程,推导了中子积分输运方程界面流算法在六角形几何情况下的数学共扼方程;介绍了该数学共扼方程求解的内、外迭代策略,并对前向方程计算程序TPHEX进行了改造,得到了常源近似情况下数学共扼方程计算程序TPHEX_J0。通过算例校验表明TPHEX_J0与TPHEX程序所计算的系统本征值符合良好,TPHEX_J0程序的计算结果是可靠的。

关键词：中子输运方程界面流方法六角形数学共扼方程

Neighboring optimal guidance using higher-order dynamics approximation with application to orbital injection problem

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Chinese Journal of Aeronautics 2024年第5期37卷 426-440页

作者： xinglun chen Ran ZHANG Huifeng li School of Astronautics Beihang UniversityBeijing 100191China

Neighboring optimal guidance,a method to obtain a suboptimal guidance law by approximately solving the first-order necessary conditions based on a nominal trajectory,is widely used in the aerospace field due to its high computational efficiency and low resource *** more advanced scenarios,the existing methods still have a problem that the guidance accuracy and optimality will seriously degrade when the actual state largely deviates from the nominal *** is mainly caused by the approximate description of the first-order conditions in terms of total flight time and nonlinear *** address this problem,a higher-order neighboring optimal guidance method is ***,a novel total flight time updating strategy,together with a normalized time scale,is presented that transforms the optimal problem with free total flight time into a more tractable optimal problem with fixed total flight ***,using the vector partial derivative method,a higher-order approximation is adopted,instead of the first-order approximation,to accurately describe the nonlinear dynamical and terminal constraints,thus obtaining a polynomially constrained quadratic optimal ***,to numerically solve the polynomially constrained quadratic optimal problem,a Newton-type iterative algorithm based on the orthogonal decomposition is *** the iterative solution within each guidance period,the corrections to control quantities and total flight time are *** proposed method is applied to a launch vehicle orbital injection problem,and simulation results show that it achieves high accuracy of orbital injection and optimality of performance index.

关键词： Optimal control Neighboring optimal guidance Launch vehicles Orbital injection Higher-order approximation

Group Decision-Making Method of Entry Policy During a Pandemic

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Tsinghua Science and Technology 2024年第1期29卷 56-65页

作者： Chunsheng Cui Baiqiu li Xianfeng chen College of Computer and Information Engineering Henan University of Economics and LawZhengzhou 450046China Tourism College Beijing Union UniversityBeijing 100101China

Omicron,the new mutant coronavirus,has spread rapidly globally,attracting close attention from different stakeholders *** complex and constantly changing epidemic situation has had a new impact on the ***,this paper focuses on the characteristics of the rapid spread of the COVID-19 variant ***,epidemic prevention experts conduct preliminary screening as part of the existing epidemic plan database according to the current local situation,after which they sort the alternatives deemed more suitable for the *** the decision-makers identify the most divergent expert group,plan for consultation and adjustments,and finally obtain the plan with the smallest *** article aims to integrate the experts'opinions with the method of minimizing the differences,which can maximize the expert consensus and help organize the schemes that best meet the epidemic *** experts'negotiation and iteration of the differences in the initial plan align with the current complex and dynamic epidemic situation and are of great significance to the rapid formulation of plans to achieve effective prevention and control.

关键词： epidemic prevention and control group decision-making alternative ranking control policy

An extended numerical model of the first exothermic peak for three dimensional printed cement-based materials

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 80-88页

作者： Wei JIANG Wenqian li Xi chen School of Materials Science and Engineering Tongji UniversityShanghai 200092China School of Civil Engineering Tongji UniversityShanghai 200092China

The first exothermic peak of cement-based material occurs a few minutes after mixing,and the properties of three dimensional(3D)printed concrete,such as setting time,are very sensitive to *** this background,based on the classical Park cement exothermic model of hydration,we propose and construct a numerical model of the first exothermic peak,taking into account the proportions of C_(3)S,C_(3)A and quicklime in *** calculated parameters are calibrated by means of relevant published exothermic test *** is found that this developed model offers a good simulation of the first exothermic peak of hydration for C_(3)S and C_(3)A proportions from 0 to 100% of cement clinker and reflects the effect of quicklime content at 8%-10%.The unique value of this research is provision of an important computational tool for applications that are sensitive to the first exothermic peak of hydration,such as 3D printing.

关键词： 3D printed cement-based materials cement hydration the first exothermic peak liquid quick-setting agent numerical model

Vision-based survey method for extraordinary loads on buildings

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 815-831页

作者： Yang li Jun chen Pengcheng WANG College of Civil Engineering Tongji UniversityShanghai 200092China China United Engineering Co.Ltd. Hangzhou 310052China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Engineering Structure Safety Shanghai Research Institute of Building Sciences Co.Ltd.Shanghai 200032China

The statistical modeling of extraordinary loads on buildings has been stagnant for decades due to the laborious and error-prone nature of existing survey methods,such as questionnaires and verbal *** study proposes a new vision-based survey method for collecting extraordinary load data by automatically analyzing surveillance *** this purpose,a crowd head tracking framework is developed that integrates crowd head detection and reidentification models based on convolutional neural networks to obtain head trajectories of the crowd in the survey *** crowd head trajectories are then analyzed to extract crowd quantity and velocities,which are the essential factors for extraordinary *** survey areas with frequent crowd movements during temporary events,the equivalent dynamic load factor can be further estimated using crowd velocity to consider dynamic effects.A crowd quantity investigation experiment and a crowd walking experiment are conducted to validate the proposed survey *** experimental results prove that the proposed survey method is effective and accurate in collecting load data and reasonable in considering dynamic effects during extraordinary *** proposed survey method is easy to deploy and has the potential to collect substantial and reliable extraordinary load data for determining design load on buildings.

关键词： load survey extraordinary load live load object detection multiple-object tracking

Comprehensive Evaluation Method for Traffic Flow Data Quality Based on Grey Correlation Analysis and Particle Swarm Optimization

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 106-128页

作者： Wei Ba Baojun chen Qi li School of Automation and Electrical Engineering Dalian Jiaotong UniversityDalian116028China Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian116023China

Nowadays,data are more and more used for intelligent modeling and prediction,and the comprehensive evaluation of data quality is getting more and more attention as a necessary means to measure whether the data are usable or ***,the comprehensive evaluation method of data quality mostly contains the subjective factors of the evaluator,so how to comprehensively and objectively evaluate the data has become a bottleneck that needs to be solved in the research of comprehensive evaluation *** order to evaluate the data more comprehensively,objectively and differentially,a novel comprehensive evaluation method based on particle swarm optimization(PSO)and grey correlation analysis(GCA)is presented in this *** first,an improved GCA evaluation model based on the technique for order preference by similarity to an ideal solution(TOPSIS)is ***,an objective function model of maximum difference of the comprehensive evaluation values is built,and the PSO algorithm is used to optimize the weights of the improved GCA evaluation model based on the objective function ***,the performance of the proposed method is investigated through parameter analysis.A performance comparison of traffic flow data is carried out,and the simulation results show that the maximum average difference between the evaluation results and its mean value(MDR)of the proposed comprehensive evaluation method is 33.24%higher than that of TOPSIS-GCA,and 6.86%higher than that of *** proposed method has better differentiation than other methods,which means that it objectively and comprehensively evaluates the data from both the relevance and differentiation of the data,and the results more effectively reflect the differences in data quality,which will provide more effective data support for intelligent modeling,prediction and other applications.

关键词： Data quality comprehensive evaluation particle swarm optimization grey correlation analysis traffic flow data