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大规模商务场景的统计管理理论
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作者 陈松蹊 陈国青 +5 位作者 常晋源 霍红 章魏 张新雨 朱雪宁 王汉生 《中国科学基金》 CSSCI CSCD 北大核心 2024年第5期733-749,共17页
大规模商务场景是科学技术进步与商业实践发展的必然产物。大规模商务场景既覆盖了面向经济主战场的商务实践,也包括国家治理相关的重要领域,还关注数字孪生为核心的新一代数字管理技术。大规模商务场景的统计管理覆盖了管理学、经济学... 大规模商务场景是科学技术进步与商业实践发展的必然产物。大规模商务场景既覆盖了面向经济主战场的商务实践,也包括国家治理相关的重要领域,还关注数字孪生为核心的新一代数字管理技术。大规模商务场景的统计管理覆盖了管理学、经济学、计算机、环境治理、数学、统计学等多个交叉学科,为管理理论的创新提供了独特机遇。如何面向大规模商务场景,发展前沿统计方法,创新管理理论是政府部门、工业界和学术界共同关心的重要问题。基于国家自然科学基金委员会第344期“双清论坛”,本文从大规模商务场景出发,围绕复杂商务场景中的“数据分析方法”“统计计算与优化方法”以及“预测理论与管理决策”三方面进行了深入探讨。基于对相关概念的清晰界定和对国内外的重要文献进行系统梳理,总结了当前国内外研究现状与前沿,分析了发展趋势和方向,凝练了该领域未来5到10年的重大关键科学问题,探讨了前沿研究方向和科学基金资助战略。 展开更多
关键词 大规模商务场景 统计管理理论 数据分析 统计计算与优化 预测理论
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基于LM-LSO算法的磷石膏堆场边坡形态与稳定性智能优化方法
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作者 李垚熠 陈国庆 +3 位作者 石明汉 周玉新 聂闻 郑成 《黄金科学技术》 CSCD 北大核心 2024年第5期882-893,共12页
大量欠稳定边坡阻碍了人类工程活动,亟需采用合理的优化方案来确保工程安全。为此,提出了基于列文伯格—马夸尔特(Levenberg-Marquardt,LM)算法和光谱优化算法(Light Spectrum Optimizer,LSO)的边坡形态智能优化方法(LM-LSO)。首先,采... 大量欠稳定边坡阻碍了人类工程活动,亟需采用合理的优化方案来确保工程安全。为此,提出了基于列文伯格—马夸尔特(Levenberg-Marquardt,LM)算法和光谱优化算法(Light Spectrum Optimizer,LSO)的边坡形态智能优化方法(LM-LSO)。首先,采用LM算法对样本数据进行非线性拟合;其次,采用拒绝不可行解方法处理稳定性系数的约束问题;最后,利用LSO搜索最优方案,并与另外4种算法进行比较分析。该方法应用于四川省某磷石膏堆场边坡优化,得到了最小挖方量的优化设计方案。该方法综合考虑了边坡优化的经济性和稳定性,保障了堆场的堆填方量和安全。 展开更多
关键词 LEVENBERG-MARQUARDT算法 光谱优化算法 非线性拟合 稳定性系数 挖方量 磷石膏堆场
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A process-oriented approach for identifying potential landslides considering time-dependent behaviors beyond geomorphological features
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作者 Xiang Sun guoqing chen +4 位作者 Xing Yang Zhengxuan Xu Jingxi Yang Zhiheng Lin Yunpeng Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期961-978,共18页
Geomorphological features are commonly used to identify potential landslides.Nevertheless,overemphasis on these features could lead to misjudgment.This research proposes a process-oriented approach for potential lands... Geomorphological features are commonly used to identify potential landslides.Nevertheless,overemphasis on these features could lead to misjudgment.This research proposes a process-oriented approach for potential landslide identification that considers time-dependent behaviors.The method integrates comprehensive remote sensing and geological analysis to qualitatively assess slope stability,and employs numerical analysis to quantitatively calculate aging stability.Specifically,a time-dependent stability calculation method for anticlinal slopes is developed and implemented in discrete element software,incorporating time-dependent mechanical and strength reduction calculations.By considering the time-dependent evolution of slopes,this method highlights the importance of both geomorphological features and time-dependent behaviors in landslide identification.This method has been applied to the Jiarishan slope(JRS)on the Qinghai-Tibet Plateau as a case study.The results show that the JRS,despite having landslide geomorphology,is a stable slope,highlighting the risk of misjudgment when relying solely on geomorphological features.This work provides insights into the geomorphological characterization and evolution history of the JRS and offers valuable guidance for studying slopes with similar landslide geomorphology.Furthermore,the process-oriented method incorporating timedependent evolution provides a means to evaluate potential landslides,reducing misjudgment due to excessive reliance on geomorphological features. 展开更多
关键词 Geomorphological features Evolution history Time-dependent stability calculation Landslides identification Qinghai-Tibet Plateau
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Numerical Investigation of the Angle of Attack Effect on Cloud Cavitation Flow around a Clark-Y Hydrofoil
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作者 Di Peng guoqing chen +1 位作者 Jiale Yan Shiping Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2947-2964,共18页
Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater vehic... Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater vehicles.The re-entrant jet and compression wave resulting from the collapse of cavity vapour are pivotal factors contributing to cavity instability.Concurrently,these phenomena significantly modulate the evolution of cavitation flow.In this paper,numerical investigations into cloud cavitation over a Clark-Y hydrofoil were conducted,utilizing the Large Eddy Simulation(LES)turbulence model and the Volume of Fluid(VOF)method within the OpenFOAM framework.Comparative analysis of results obtained at different angles of attack is undertaken.A discernible augmentation in cavity thickness is observed concomitant with the escalation in attack angle,alongside a progressive intensification in pressure at the leading edge of the hydrofoil,contributing to the suction force.These results can serve as a fundamental point of reference for gaining a deeper comprehension of cloud cavitation dynamics. 展开更多
关键词 Cloud cavitation re-entrant jet compression wave clark-Y hydrofoil
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Study on the Change of Eco-Environmental Quality in Jiufeng Mountain Area Based on InVEST Model
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作者 Xiping Li Weixian Li +3 位作者 Ce Gao Luying Shao guoqing chen Shaifei Wang 《Open Journal of Ecology》 2022年第1期36-50,共15页
Habitat is not only an important place for animals and plants to inhabit and reproduce, but also the basis of human survival and development. With the large-scale development of mineral resources, land use types have ... Habitat is not only an important place for animals and plants to inhabit and reproduce, but also the basis of human survival and development. With the large-scale development of mineral resources, land use types have changed sharply, fragile habitats tend to collapse, and the future sustainable development has lost a stable carrier. Habitat quality is a comprehensive expression of the interaction of many factors such as land, biology and water resources for many years. Natural factors are the most direct factors affecting habitat quality, and human activities are the most intense factors. The habitat module of invest model was used to evaluate the changes and temporal and spatial characteristics of habitat quality in Jiufeng Mountain from 1990 to 2018. It is found that the habitat quality in Jiufeng Mountain area shows a downward trend, and the ecological environment is very fragile. The high value areas of eco-environmental quality are mainly distributed in mountainous and hilly areas with high vegetation coverage;The low value areas of eco-environmental quality are mainly distributed in industrial and mining land and gully areas. With the development of society and economy and the development of mining industry in Jiufengshan area, the area of construction land is also increasing. 展开更多
关键词 Habitat Quality Land Use Change InVEST Model Jiufengshan Area
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Genetic dissection of husk number and length across multiple environments and fine-mapping of a major-effect QTL for husk number in maize(Zea mays L.) 被引量:3
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作者 Guangfei Zhou Yuxiang Mao +7 位作者 Lin Xue guoqing chen Huhua Lu Mingliang Shi Zhenliang Zhang Xiaolan Huang Xudong Song Derong Hao 《The Crop Journal》 SCIE CSCD 2020年第6期1071-1080,共10页
Husk number(HN)and husk length(HL)influence the mechanical harvesting of maize grain.We investigated the genetic basis of HN and HL using a population of 204 recombinant inbred lines phenotypically evaluated in five e... Husk number(HN)and husk length(HL)influence the mechanical harvesting of maize grain.We investigated the genetic basis of HN and HL using a population of 204 recombinant inbred lines phenotypically evaluated in five environments.The two husk traits showed broad phenotypic variation and high heritability.Nine stable quantitative trait loci(QTL)were identified by single-environment mapping,comprising four QTL for HN and five for HL,and three QTL explained>10%of the phenotypic variation.Joint mapping revealed 22 additive QTL and 46 epistatic QTL.Both additive and epistatic(additive×additive)effects as well as a few large-effect QTL and some minor-effect QTL appeared to contribute to the genetic architecture of HN and HL.The QTL for HN located on chromosome 7,q HN7,which accounted for^20%of phenotypic variation,was detected in all five environments.q HN7 was fine-mapped to a 721.1 kb physical region based on the maize B73 Ref Gen_v3 genome assembly.Within this interval,four genes associated with plant growth and development were selected as candidate genes.The results will be useful for improvement of maize husk traits by molecular breeding and provide a basis for the cloning of q HN7. 展开更多
关键词 Zea mays L. Husk number Husk length Quantitative trait locus Fine mapping
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基于IOWGA算子的中国碳排放量的组合预测 被引量:1
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作者 陈国庆 王辉艳 龙云安 《工业经济论坛》 2017年第5期33-41,共9页
中国的经济已经进入新常态,为了统筹兼顾经济和环境,政府已将碳减排提到了前所未有的战略高度。碳排放量的精确预测可以为碳减排提供重要的参考,在总结国内外所使用的碳预测方法,并提出这些方法的局限。因此,取1980~2015年中国碳排放量... 中国的经济已经进入新常态,为了统筹兼顾经济和环境,政府已将碳减排提到了前所未有的战略高度。碳排放量的精确预测可以为碳减排提供重要的参考,在总结国内外所使用的碳预测方法,并提出这些方法的局限。因此,取1980~2015年中国碳排放量为样本数据,构建诱导有序加权几何平均(IOWGA)算子的组合预测模型,对中国未来五年的碳排放量进行预测,并将结果和单项预测结果比较。就碳减排问题提出相应的对策建议,以期对碳减排的政策制定提供理论指导。 展开更多
关键词 碳排放 IOWGA算子 组合预测 MATLAB
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Service-Driven Coded Forward Scheme Based on Streaming Transmission Model for Lunar Space Communication Networks 被引量:1
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作者 Shushi Gu Ye Wang +1 位作者 guoqing chen Shuo Shi 《China Communications》 SCIE CSCD 2020年第7期15-26,共12页
With the rapid development of lunar exploration,a large amount of scientific data and media stream service needs to be transmitted through Lunar Space Communication Networks(LSCNs).Due to limited transmitter power and... With the rapid development of lunar exploration,a large amount of scientific data and media stream service needs to be transmitted through Lunar Space Communication Networks(LSCNs).Due to limited transmitter power and intermittent,long delay and packet loss connections,the reliable and efficient multi-priority services’transmission in LSCNs becomes an urgent problem.Firstly,we propose a Streaming Transmission Model(STM)based on temporal and spatial topology graph to describe the delay and energy consumption for data transmission in LSCNs.Then,we further devise a Coded Forward Scheme based on STM,termed CFS-STM,to achieve multi-priority service in two steps:i).Link Stability Function(LSF)is established by solving an optimization problem to choose the appropriate single-hop path.ii).Raptor code is employed to further save delay and energy with adjustable code-rate according to the different channel conditions.Experiment results show that,CFS-STM can significantly improve the transmission efficiency of multi-service priority streaming delivery in LSCNs. 展开更多
关键词 STREAMING service DELAY
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Antifungal Activity of Schinifoline Against Candida Albicans in Caenorhabditis Elegans
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作者 chengjie Shu Mengli Zhang +3 位作者 Weiming Zhang Shihong Ma guoqing chen Baojun Shi 《Phyton-International Journal of Experimental Botany》 SCIE 2019年第3期317-324,共8页
Zanthoxylum schinifolium has been used as spices and traditional medicine in China for hundreds of years.A variety of active substances have been isolated from Zanthoxylum schinifolium using biological and chemical te... Zanthoxylum schinifolium has been used as spices and traditional medicine in China for hundreds of years.A variety of active substances have been isolated from Zanthoxylum schinifolium using biological and chemical techniques.Among these substances,the effect of schinifoline has gradually attracted much attention.Candida albicans is one of the most common pathogens isolated from the gastrointestinal tract,vagina,and mouth in healthy individuals.In a healthy population,there are various mechanisms in host,such as the microbial flora,the epithelial barriers,and the innate immune system,that can control the presence of Candida albicans.However,when host immunity is compromised,an invasive fungal infection is more likely to occur.In this study,we explored the antifungal activity of schinifoline against Candida albicans in Caenorhabditis elegans.To determine the optimal concentration of schinifoline,we investigated the lifespan,defecation cycle and locomotion behavior of Caenorhabditis elegans after treatment with schinifoline.In addition,we examined colony formation in the intestine of Caenorhabditis elegans after Candida albicans infection.The results indicated that 100 and 200 mg/L of schinifoline could prolonged the lifespan,shorten the defecation cycle and increased the locomotion behavior of Caenorhabditis elegans,with 100 mg/L of schinifoline being the optimal concentration.Moreover,100 mg/L of schinifoline increased the lifespan of Caenorhabditis elegans after infection and inhibited the colony formation of Candida albicans in Caenorhabditis elegans intestine.Therefore,we concluded that schinifoline exhibits anti-fungal effects and its potential use as natural drugs should be further explored in future studies. 展开更多
关键词 Schinifoline fungistasis ANTI-AGING Candida albicans Caenorhabditis elegans
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Translation of basic science into clinical medicine in man-agement for neurogenic bladder
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作者 Limin Liao guoqing chen Fan Zhang 《Journal of Translational Neuroscience》 2016年第1期32-36,共5页
Neurogenic bladder ( NB) dysfunction caused by spinal cord injury ( SCI ) or diseases of the central nervous system or peripheral nerves is a major medical and social problem. Traditional treatments to NB include ... Neurogenic bladder ( NB) dysfunction caused by spinal cord injury ( SCI ) or diseases of the central nervous system or peripheral nerves is a major medical and social problem. Traditional treatments to NB include medication, injection of Botulinum toxin A into the detrusor, neuromodulation and surgery. There are also emerging approaches, such as tissue engineering, stem cell transplantation and gene therapy. In recent years, we have carried out explorations in both therapeutic areas and tried to translate basic research into clinical practice. This paper reviews our work in this regard, and provides references for future research. 展开更多
关键词 neurogenic bladder NB MEDICATION urinary tract reconstruction NEUROMODULATION stem cell transplantion gene therapy
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Genetic diversity of RNA viruses infecting invertebrate pests of rice
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作者 Haoran Wang Shufen Chao +13 位作者 Qing Yan Shu Zhang guoqing chen Chonghui Mao Yang Hu Fengquan Yu Shuo Wang Liang Lv Baojun Yang Jiachun He Songbai Zhang Liangsheng Zhang Peter Simmonds Guozhong Feng 《Science China(Life Sciences)》 SCIE CAS CSCD 2024年第1期175-187,共13页
Invertebrate species are a natural reservoir of viral genetic diversity,and invertebrate pests are widely distributed in crop fields.However,information on viruses infecting invertebrate pests of crops is limited.In t... Invertebrate species are a natural reservoir of viral genetic diversity,and invertebrate pests are widely distributed in crop fields.However,information on viruses infecting invertebrate pests of crops is limited.In this report,we describe the deep metatranscriptomic sequencing of 88 invertebrate samples covering all major invertebrate pests in rice fields.We identified 296 new RNA viruses and 13 known RNA viruses.These viruses clustered within 31 families,with many highly divergent viruses constituting potentially new families and genera.Of the identified viruses,13 RNA viruses clustered within the Fiersviridae family of bacteriophages,and 48 RNA viruses clustered within families and genera of mycoviruses.We detected known rice viruses in novel invertebrate hosts at high abundances.Furthermore,some novel RNA viruses have genome structures closely matching to known plant viruses and clustered within genera of several plant virus species.Fortyfive potential insect pathogenic RNA viruses were detected in invertebrate species.Our analysis revealed that host taxonomy plays a major role and geographical location plays an important role in structuring viral diversity.Cross-species transmission of RNA viruses was detected between invertebrate hosts.Newly identified viral genomes showed extensive variation for invertebrate viral families or genera.Together,the large-scale metatranscriptomic analysis greatly expands our understanding of RNA viruses in rice invertebrate species,the results provide valuable information for developing efficient strategies to manage insect pests and virus-mediated crop diseases. 展开更多
关键词 invertebrate species metatranscriptome viral diversity viral transmission viral genomes
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GMAT:A Graph Modeling Method for Group Preference Prediction
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作者 Xiangyu Li Xunhua Guo guoqing chen 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2024年第4期475-493,共19页
Preference prediction is the building block of personalized services,and its implementation at the group level helps enterprises identify their target customers effectively.Existing methods for preference prediction m... Preference prediction is the building block of personalized services,and its implementation at the group level helps enterprises identify their target customers effectively.Existing methods for preference prediction mainly focus on behavioral interactions to extract the associations between groups and products,ignoring the importance of other auxiliary records(e.g.,online reviews and social tags)in association detection.This paper proposes a novel method named GMAT for group preference prediction,aiming to collectively detect the sophisticated association patterns from user generated content(UGC)and behavioral interactions.In doing so,we construct a tripartite graph to collaborate these two types of data,and design a deep-learning algorithm with mutual attention module for generating the contextualized representations of groups and products.Extensive experiments on two real-world datasets show that GMAT is superior to other baselines in terms of group preference prediction.Additionally,GMAT is able to improve prediction accuracy compared with its different variants,further verifying the proposed method’s effectiveness on association pattern detection. 展开更多
关键词 Group preference UGC tripartite graph deep learning
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A bilateral heterogeneous graph model for interpretable job recommendation considering both reciprocity and competition
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作者 Xiaowei SHI Qiang WEI guoqing chen 《Frontiers of Engineering Management》 CSCD 2024年第1期128-142,共15页
Amidst the inefficiencies of traditional job-seeking approaches in the recruitment ecosystem, the importance of automated job recommendation systems has been magnified. However, existing models optimized to maximize u... Amidst the inefficiencies of traditional job-seeking approaches in the recruitment ecosystem, the importance of automated job recommendation systems has been magnified. However, existing models optimized to maximize user clicks for general product recommendations prove inept in addressing the unique challenges of job recommendation, namely reciprocity and competition. Moreover, sparse data on online recruitment platforms can further negatively impact the performance of existing job recommendation algorithms. To counteract these limitations, we propose a bilateral heterogeneous graph-based competition iteration model. This model comprises three integral components: 1) two bilateral heterogeneous graphs for capturing multi-source information from people and jobs and alleviating data sparsity, 2) fusion strategies for synthesizing attributes and preferences to produce mutually beneficial job matches, and 3) a competition-enhancing strategy for dispersing competition realized through a two-stage optimization algorithm. Augmented by granular attention mechanisms for enhanced interpretability, the model’s efficacy, competition dispersion, and interpretability are validated through rigorous empirical evaluations on a real-world recruitment platform. 展开更多
关键词 job recommendation COMPETITION RECIPROCITY INTERPRETABILITY
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Brainstem opioid peptidergic neurons regulate cough reflexes in mice
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作者 Haicheng Lu guoqing chen +17 位作者 Miao Zhao Huating Gu Wenxuan Zheng Xiating Li Meizhu Huang Dandan Geng Minhui Yu Xuyan Guan Li Zhang Huimeng Song Yaning Li Menghua Wu Fan Zhang Dapeng Li Qingfeng Wu Congping Shang Zhiyong Xie Peng Cao 《The Innovation》 EI 2024年第6期50-61,共12页
Cough is a vital defensive reflex for expelling harmful substances from the airway.The sensory afferents for the cough reflex have been intensively studied.However,the brain mechanisms underlying the cough reflex rema... Cough is a vital defensive reflex for expelling harmful substances from the airway.The sensory afferents for the cough reflex have been intensively studied.However,the brain mechanisms underlying the cough reflex remain poorly understood.Here,we developed a paradigm to quantitatively measure cough-like reflexes in mice.Using this paradigm,we found that prodynorphin-expressing(Pdyn+)neurons in the nucleus of the solitary tract(NTS)are critical for capsaicin-induced cough-like reflexes.These neurons receive cough-related neural signals from Trpv1+vagal sensory neurons.The activation of Pdyn+NTS neurons triggered respiratory responses resembling cough-like reflexes.Among the divergent projections of Pdyn+NTS neurons,a glutamatergic pathway projecting to the caudal ventral respiratory group(cVRG),the canonical cough center,was necessary and sufficient for capsaicin-induced cough-like reflexes.These results reveal that Pdyn+NTS neurons,as a key neuronal population at the entry point of the vagus nerve to the brainstem,initiate cough-like reflexes in mice. 展开更多
关键词 RESPIRATORY OPIOID COUGH
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Effect of drum structure on particle mixing behavior based on DEM method 被引量:3
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作者 Ganggang Xu Yong Zhang +2 位作者 Xigang Yang guoqing chen Baosheng Jin 《Particuology》 SCIE EI CAS CSCD 2023年第3期74-91,共18页
The optimization of the drum structure is beneficial to improve the particle motion and mixing in rotary drums.In this work,two kinds of drum structures,Lacy cylinder drum(LC)and Lacy-lifters cylinder drum(LLC),are de... The optimization of the drum structure is beneficial to improve the particle motion and mixing in rotary drums.In this work,two kinds of drum structures,Lacy cylinder drum(LC)and Lacy-lifters cylinder drum(LLC),are developed on the basic of cylinder drum to enhance the heat transfer area.The particle motion and mixing process are simulated by DEM method.Based on the grid independence and model validation,the contact number between particles and wall,particle velocity profile,thickness of active layer,particle exchange coefficient,particle concentration profile and mixing index are demonstrated.The influences of the drum structure and the operation parameters are further evaluated.The results show that the contact number between particles and wall is improved in LC and LLC compared to cylinder drum.The particle velocity in LC is higher than that in cylinder drum at high rotating speed,and the particle velocity of the particle falling region is significantly improved in LLC.Compared to cylinder drum and LC,the thickness of active layer in LLC is smaller,while the local particle mixing quality is proved to be the best in the active region.In addition,the particle exchange coefficients between static region and active region in the three drums are compared and LLC is found tending to weaken the particle flow.Besides,the fluctuations of particle concentration in the active region,static region,and boundary region are weakened in LLC,and the equilibrium state is reached earlier.In addition,the overall particle mixing performance in cylinder drum,LC and LLC is analyzed.The particle mixing performance in cylinder drum is the worst,while the difference in mixing quality of LC and LLC depends on the operation conditions. 展开更多
关键词 Rotating drum Drum structure Particle velocity profile Thickness of active layer Particle mixing
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Analysis of interaction between dislocation and interface of aluminum matrix/second phase from electronic behavior
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作者 Qianxing Yin guoqing chen +6 位作者 Xi Shu Binggang Zhang Chun Li Zhibo Dong Jian Cao Rong An Yongxian Huang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第5期78-90,共13页
The inhibitory effect of the second phase on dislocation movement has long been deemed as a great con-tribution to the strengthening of alloys.We investigate the electronic behavior at theα-Al matrix/second phase int... The inhibitory effect of the second phase on dislocation movement has long been deemed as a great con-tribution to the strengthening of alloys.We investigate the electronic behavior at theα-Al matrix/second phase interface to explore its inhibitory effect on dislocation movement.This work focuses on the dif-ficulty in dislocation movement on the interface ofα-Al/Al_(3)Sc,α-Al/θ’(Al_(2)Cu),andα-Al/T_(1)(Al_(2)CuLi)of aluminum-lithium-scandium alloy based on detailed transmission electron microscopy investigation and electron transport calculation.The more drastic the electron transport between two atoms at the inter-face,the more intense the interaction between them,corresponding to the larger difficulty in breaking and forming bonds between them during the movement process of the extra half plane of dislocation on the interface.The calculated difference in density of valence electrons and differential charge density atα-Al/second phase interface reveals that Al_(3)Sc is characterized by the largest resistance to dislocation movement compared toθ’(Al_(2)Cu)and T_(1)(Al_(2)CuLi).The large differential charge density between the in-terface of(100)Al_(3)Sc/(100)Al demonstrates the strong bonds betweenα-Al and Al_(3)Sc and the large difficulty for the extra half plane of dislocation to form or break bonds during the movement process atα-Al/Al_(3)Sc interface.The dislocation pile-up indicates a discernible hindering effect of theα-Al/Al_(3)Sc interface on dislocation movement.The hindering effect presented byα-Al/Al_(3)Sc interface is favorable for the tensile strength. 展开更多
关键词 Dislocations Microstructural interface Aluminum alloy Electron transport First-principles calculation
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Diaporthe species occurring on citrus in China 被引量:17
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作者 Feng Huang Xin Hou +4 位作者 Megan M Dewdney Yushi Fu guoqing chen Kevin D Hyde Hongye Li 《Fungal Diversity》 SCIE 2013年第4期237-250,共14页
Diaporthe species are important pathogens of a wide range of hosts including many economically important crops.Diaporthe citri is generally accepted to cause melanose of Citrus fruits,leaves and shoots;stem-end rot of... Diaporthe species are important pathogens of a wide range of hosts including many economically important crops.Diaporthe citri is generally accepted to cause melanose of Citrus fruits,leaves and shoots;stem-end rot of fruits and gummosis of perennial branches.In this study,147 strains of Diaporthe were isolated from diseased leaves,twigs,fruits and branches of Citrus from Shaanxi,Zhejiang,Guangxi,Fujian,Guangdong,Jiangxi,Hunan,Chongqing and Shanghai and identified by morphology and molecular analysis of nuclear ribosomal internal transcribed spacer(ITS),partial sequences of translation elongation factor 1-α(EF 1-α),tubulin(TUB)and calmodulin(CAL)genes.All strains from Citrus clustered in three clades.Diaporthe citri was the predominant species and is compared with strains from Florida,USA,where this species was first collected and described.Two new taxa differing from D.citri are described as D.citriasiana and D.citrichinensis in this paper.Inoculation tests indicate that all three species are able to cause stem-end rot of fruits,while only D.citri could cause melanose on leaves. 展开更多
关键词 Diaporthe citri Melanose MORPHOLOGY PHOMOPSIS Phylogenetic analysis
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烟草废弃物中的难降解有机物的微生物降解研究进展 被引量:10
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作者 郑秀成 陈泽裕 +2 位作者 陈国庆 李骏 钟卫鸿 《微生物学报》 CAS CSCD 北大核心 2020年第12期2650-2663,共14页
烟草废弃物的资源化利用及无害处理过程,需要利用微生物高效降解其中的难降解物质,如木质素与尼古丁。本文主要综述烟草废弃物中难降解物质的生物降解研究进展。迄今,已经发现了不少木质素和尼古丁的微生物降解菌株,对其降解机理及应用... 烟草废弃物的资源化利用及无害处理过程,需要利用微生物高效降解其中的难降解物质,如木质素与尼古丁。本文主要综述烟草废弃物中难降解物质的生物降解研究进展。迄今,已经发现了不少木质素和尼古丁的微生物降解菌株,对其降解机理及应用已有不少研究报道,但其在烟草废弃物处理中的应用方面报道较少。木质素和尼古丁降解菌可以用于废次烟叶(烟梗)木质素的消减和尼古丁去除,但同时也需要考察菌株的降解能力和应用环境的适用性。具备降解木质素和尼古丁双重功能的菌株更有应用前景,但迄今发现较少。基于全基因组分析和微生物组学技术的复合菌群的研究也是重要的研究方向,将推动含木质素和尼古丁等多种难降解物质的废次烟叶的处置技术发展和实际应用。 展开更多
关键词 烟草废弃物 木质素 尼古丁 微生物 降解 微生物组
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Phyllosticta species associated with citrus diseases in China 被引量:8
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作者 Xinghong Wang guoqing chen +3 位作者 Feng Huang Jingze Zhang Kevin D.Hyde Hongye Li 《Fungal Diversity》 SCIE 2012年第1期209-224,共16页
Phyllosticta species associated with diseases of four commercial Citrus species grown in China are reported.Totally,496 Phyllosticta strains were isolated from mandarins(Citrus reticulata),pomeloes(C.maxima),oranges(C... Phyllosticta species associated with diseases of four commercial Citrus species grown in China are reported.Totally,496 Phyllosticta strains were isolated from mandarins(Citrus reticulata),pomeloes(C.maxima),oranges(C.sinensis)and lemons(C.limon)in the main citrus producing regions across China,and 74 strains were selected for phylogenetic analysis.Analyses inferred from the sequences of internal transcribed spacer region(ITS1,5.8S nrDNA and ITS2),partial translation elongation factor 1-alpha(TEF1)and partial actin gene(ACT),showed these representative Phyllosticta isolates clustered in four distinct clades corresponding to three known,and one undescribed species.The newly resolved taxon,Phyllosticta citrichinaensis was isolated from leaves and fruits of all four Citrus species and is introduced in this paper.This taxon caused minor damage,showing irregular spots or freckles.Phyllosticta citriasiana,associated with tan spot of pomeloes,was isolated only from pomeloes,and never from lemons,mandarins and oranges.Phyllosticta citricarpa,the citrus black spot pathogen,which is presently subjected to phytosanitary legislation in the EU and United States,was isolated from lemons,mandarins and oranges,but never from pomeloes.The isolates of P.citricarpa clustered in two subclades,one from mandarins,the other from oranges and lemons.P.capitalensis was isolated from all four Citrus species as an endophyte,causing false melanose,or together with P.citricarpa or P.citriasiana.Morphological,cultural and biochemical characters were consistent with the results of phylogenetic analysis.In addition,a specific primer pair Pca8/ITS4 was designed and selected,and its corresponding PCR procedure was developed for the detection of P.citriasiana in this study. 展开更多
关键词 Citrus black spot disease Biochemical character PHYLOGENY Morphology RUTACEAE Species-specific primer
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Users Intention for Continuous Usage of Mobile News Apps:the Roles of Quality,Switching Costs,and Personalization 被引量:3
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作者 Qiongwei Ye Yumei Luo +3 位作者 guoqing chen Xunhua Guo Qiang Wei Shuyan Tan 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2019年第1期91-109,共19页
Mobile news apps have emerged as a significant means for learning about latest news and trends. However, in light of numerous news apps and information overload, motivating users to adopt one app is a major concern fo... Mobile news apps have emerged as a significant means for learning about latest news and trends. However, in light of numerous news apps and information overload, motivating users to adopt one app is a major concern for both the industry and academia. Therefore, considering the attributes of mobile news and the debate on switching costs in the Internet context, based on the expectation-confirmation model (ECM), this study suggests that switching costs still exist and have a significant moderating effect on user satisfaction and continuous usage of mobile news apps. Furthermore, the different influences of information quality, system quality and service quality on continuance intention, user satisfaction and switching costs are discussed, showing that quality of information has a significant impact on users’ continuous usage of mobile news apps through increasing perceived usefulness, whereas personalized service quality have stronger effects through increasing user satisfaction and switching costs. 展开更多
关键词 PERSONALIZED recommendation switching costs mobile news APPS expectation-confirmation model
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