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Frontiers in Energy 2022年第4期16卷 613-628页

作者： Yumei Zhang Pengfei JIE Chunhua LIU Jing LI School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Engineering and Technology R&D Center of Clean Air Conditioning in Colleges of Shandong Shandong Huayu University of TechnologyDezhou 253000China China Environmental Resources Technology Co. LtdBeijing 100012China

The increase of insulation thickness(IT)results in the decrease of the heat demand and heat medium temperature.A mathematical model on the optimum environmental insulation thickness(OEIT)for minimizing the annual total environmental impact was established based on the amount of energy and energy grade reduction.Besides,a case study was conducted based on a residential community with a combined heat and power(CHP)-based district heating system(DHS)in Tianjin,China.Moreover,the effect of IT on heat demand,heat medium temperature,exhaust heat,extracted heat,coal consumption,carbon dioxide(CO_(2))emissions and sulfur dioxide(SO_(2))emissions as well as the effect of three types of insulation materials(i.e.,expanded polystyrene,rock wool and glass wool)on the OEIT and minimum annual total environmental impact were studied.The results reveal that the optimization model can be used to determine the OEIT.When the OEIT of expanded polystyrene,rock wool and glass wool is used,the annual total environmental impact can be reduced by 84.563%,83.211%,and 86.104%,respectively.It can be found that glass wool is more beneficial to the environment compared with expanded polystyrene and rock wool.

关键词： optimum environmental insulation thickness heat medium temperature energy grade extracted heat exhaust heat

Remote Data Auditing for Cloud-Assisted WBANs with Pay-as-You-Go Business Model

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Chinese Journal of Electronics 2023年第2期32卷 248-261页

作者： LI yumei zhang Futai School of Computer Science Hubei University of Technology Fujian Provincial Key Laboratory of Network Security and Cryptology College of Computer and Cyber SecurityFujian Normal University

As an emerging technology, cloud-assisted wireless body area networks(WBANs) provide more convenient services to users. Recently, many remote data auditing protocols have been proposed to ensure the data integrity and authenticity when data owners outsourced their data to the cloud. However, most of them cannot check data integrity periodically according to the pay-as-you-go business model. These protocols also need high tag generation computation overhead, which brings a heavy burden for data owners. Therefore, we construct a lightweight remote data auditing protocol to overcome all above drawbacks. Our work can be deployed in the public environment without secret channels.It makes use of certificate-based cryptography which gets rid of certificate management problems, key escrow problems, and secret channels. The security analysis illustrates that the proposed protocol is secure. Moreover, the performance evaluation implies that our work is available in cutting down computation and communication overheads.

关键词： Cloud-assisted wireless body area networks Periodic auditing Certificate-based cryptography Pay-as-you-go business model Public environment

The multiple roles of crop structural change in productivity,nutrition and environment in China:A decomposition analysis

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Journal of Integrative Agriculture 2024年第5期23卷 1763-1773页

作者： Xiangyang zhang Yumei Zhang Shenggen Fan College of Economics and Management China Agricultural UniversityBejing 100083China Academy of Global Food Economics and Policy China Agricultural UniversityBejing 100083China

China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other crops.As a result,land productivity,nutrient supply,and carbon emissions have changed.How to reallocate limited farmland among crops to achieve the multiple goals of agrifood systems becomes an important issue.This study explores the sources of land productivity and nutrition supply growth and carbon emissions reduction,and identifies the multiple roles of crop structural change from 2003 to 2020 based on a decomposition analysis.The results reveal that the growth within crops is still the primary driver in land productivity and nutrition supply and the reduction in carbon emissions.However,structural change also plays various roles at different periods.From 2003 to 2010,crop structural change increased the total calorie supply but lowered land productivity and contributed at least 70%of the total growth of carbon emissions.The crop structure was relatively stable,and their effects were modest from 2010 to 2015.From 2015 to 2020,the crop structural change began to play a greater role and generate synergistic effects in improving land productivity,micronutrient supply,and reducing carbon emissions,contributing to approximately a quarter of the growth of land productivity and 30%of total carbon emissions reduction.These results suggest that strategies for crop structural change should comprehensively consider its multiple impacts,aiming to achieve co-benefits while minimizing trade-offs.

关键词： crop structural change land productivity nutrition carbon emissions

Uridine dynamic administration affects the circadian variation of bile acid metabolism in high-fat-diet-fed mice

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BIOCELL 2022年第11期46卷 2433-2442页

作者： TIANTIAN ZHOU Yumei Zhang JUAN zhang CHUNYAN XIE ZHENYA ZHAI XIN WU CAS Key Laboratory of Agri-Ecological Processes in Subtropical Region Institute of Subtropical Agriculturethe Chinese Academy of SciencesHunan Provincial Engineering Research Center for Healthy Livestock and Poultry ProductionChangsha410125China Institute of Biological Resources Jiangxi Academy of SciencesNanchang330096China University of Chinese Academy of Sciences Beijing100049China

High-fat diet(HFD)is demonstrated to disturb the bile acid metabolism.The rhythm of bile acid metabolism can also be affected by uridine,whose metabolism exhibits a daily rhythm.However,the mechanism of dynamic uridine administration affecting bile acid during HFD remains unclear.In this study,C57BL/6J mice were fed HFD(the control group;CON)or HFD with oral administration of uridine in the daytime(DUR)and nighttime(NUR)to investigate the mechanism of the effect of uridine on the bile acid.This study showed that the mRNA expression of uridine transporters and circadian clock genes in the jejunum was affected by zeitgeber time(ZT)(P<0.001).Genes related to the metabolism of pyrimidines in the liver showed a high dependence on daily rhythm(P<0.01),and DUR remarkably up-regulated the expression of ribonucleotide reductase regulatory subunit M2(RRM2)(P<0.05)compared to the CON group.Importantly,the mRNA expression of bile acids nuclear receptors,bile acid synthesis,and transporters in the liver showed significantly rhythmically changed(P<0.05),and the expression of cholesterol 7-alpha-hydroxylase(CYP7A1),fibroblast growth factor receptor 4(FGFR4),Na^(+)/taurocholate co transporting polypeptide(NTCP),and bile salt export pump(BSEP)mRNAs of mice with uridine administration increased significantly(P<0.05).The mRNA expression of the transporters of cholesterol and bile acids in the ileum was also affected by ZT(P<0.01)and significantly dependent on uridine administration(P<0.05).The expression of FXR and SHP was significantly affected by ZT and uridine,respectively.In conclusion,dynamic administration of uridine could regulate the rhythm of gene expression of pyrimidine and bile acid metabolism in the liver and ileum of HFD-fed mice,which contributed to the further study of circadian rhythmic physiological and pathological changes of bile acids.

关键词： Diurnal rhythm Uridine Dynamic Bile acids metabolism High-fat diet

Research on the scatter features of the PKiKP/PcP amplitude ratio and the inner core boundary density contrasts beneath Northeast Asia

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Science China Earth Sciences 2021年第5期64卷 716-727页

作者： Haodong zhang Yinshuang AI yumei HE Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100049China University of Chinese Academy of Sciences Beijing 100101China

Quantifying the density contrasts of the Earth’s inner core boundary(ICB)is crucial to understand core-mantle coupling and the generation of the geodynamo.The PKiKP/PcP amplitude ratio is commonly used to obtain the density contrast at the ICB,but its applications are limited by scattered observed data.In this study,we selected the PKiKP and PcP phases reflected at the same region of inner-core and core-mantle boundaries beneath Northeast Asia from different earthquakes for the first time,and the observations suggested that the PKiKP/PcP amplitude ratio is widely scattered.We also compared the PKiKP and PcP amplitudes,which demonstrated that the scatter cannot be attributed only to ICB anomalies but might also arise from raypath differences and heterogeneities throughout the crust and mantle.By fitting the observed PKiKP/PcP amplitude ratio,we obtained a density contrast of approximately 0.65 g cm^(-3) and a compressional velocity contrast of approximately 0.87 km s^(-1) at the ICB beneath Northeast Asia.The larger contrast values indicate the possible occurrence of local crystallization occurring at the inner core surface.

关键词： Northeast Asia Inner core boundary PKiKP/PcP amplitude ratio Density contrast

An indoor fusion navigation algorithm using HV-derivative dynamic time warping and the chicken particle flter

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Satellite Navigation 2022年第1期3卷 167-184,I0005页

作者： Jian Chen Shaojing Song yumei Gong Shanxin zhang School of Computer and Information Engineering Shanghai Polytechnic UniversityShanghai 200000China School of Computer and Information Engineering Shandong Normal UniversityJinanChina

The use of dead reckoning and fngerprint matching for navigation is a widespread technical method.However,fngerprint mismatching and low fusion accuracy are prevalent issues in indoor navigation systems.This work presents an improved dynamic time warping and a chicken particle flter to handle these two challenges.To generate the Horizontal and Vertical(HV)fngerprint,the pitch and roll are employed instead of the original fngerprint intensity to extract the horizontal and vertical components of the magnetic feld fngerprint.Derivative dynamic time warping employs the HV fngerprint in its derivative form,which receives higher-level features because of the consideration of fngerprint shape information.Chicken Swarm Optimization(CSO)is used to enhance particle weights,which minimizes position error to tackle the particle impoverishment problem for a fusion navigation system.The results of the experiments suggest that the enhanced algorithm can improve indoor navigation accuracy signifcantly.

关键词： An indoor fusion navigation algorithm HV-derivative dynamic time warping Chicken particle flter

Understory plant diversity and phenolic allelochemicals across a range of Eucalyptus grandis plantation ages

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林业研究:英文版 2023年第5期34卷 1577-1590页

作者： Jinjin Li yumei Huang Lianghua Chen Shun Gao Jian zhang Danju zhang Sichuan Provincial Key Laboratory of Ecological Forestry Engineering College of ForestrySichuan Agricultural UniversityWenjiang 611130ChengduChina College of Landscape Architecture Sichuan Agricultural UniversityWenjiang 611130ChengduChina

Allelopathy is an important mechanism in Eucalyptus plantations that causes detrimental impacts on understory diversity.Phenolic compounds are the main allelochemicals suppressing understory plants.However,the dynamic changes in phenolic allelochemicals and their relationship with understory diversity with increasing age of Eucalyptus plantations remain largely unclear.In this study,the understory plant diversity was assessed and phenolic compounds identified from leaf litter,roots,and rhizosphere soil samples in a Eucalyptus grandis plantation at two-year intervals for ten years using ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The abundance and diversity of under story plant species were lowest in 4-year-old plantations and increased significantly with age.Seven phenolic acids and 10 flavonoids were identified from leaf litter,roots,and rhizosphere soils.Most of the potential phenolic allelochemicals,such as salicylic acid,gallic acid,4-hydroxybenzoic acid,and epicatechin,were more abundant in younger plantations,especially at4 years old.The concentrations of phenolic compounds in the rhizosphere zone were significantly lower than in litter and root samples and did not change significantly with an increase in age.Notably,phenolic compounds contributed more to the variation in the understory plants than soil factors.Hydroxyphenyllactic acid,ellagic acid,quercetin,salicylic acid,and 4-hydroxybenzoic acid were the main phenolic compounds explaining the variation in plant diversity with plantation age.These findings indicate that young E.grandis plantations,especially at four years of age,merit a greater focus because of their lower understory plant diversity and higher allelopathic potential.

关键词： Eucalyptus grandis Phenolic compounds Understory plant diversity Plantation age

Identification for the Low-Contrast Image Signal with Regularized Variational Term and Dynamical Saturating Nonlinearity

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Journal of Systems Science & Complexity 2023年第3期36卷 1089-1102页

作者： zhang Ning MA yumei PAN Zhenkuan HUANG Baoxiang WANG Dongcheng College of Computer Science&Technology Qingdao UniversityQingdao 266071China

In recent years,image processing based on stochastic resonance(SR)has received more and more attention.In this paper,a new model combining dynamical saturating nonlinearity with regularized variational term for enhancement of low contrast image is proposed.The regularized variational term can be setting to total variation(TV),second order total generalized variation(TGV)and non-local means(NLM)in order to gradually suppress noise in the process of solving the model.In addition,the new model is tested on a mass of gray-scale images from standard test image and low contrast indoor color images from Low-Light dataset(LOL).By comparing the new model and other traditional image enhancement models,the results demonstrate the enhanced image not only obtain good perceptual quality but also get more excellent value of evaluation index compared with some previous methods.

关键词： Dynamical saturating nonlinearity image enhancement low contrast regularized variational term stochastic resonance(SR)

Determination of physical properties for the mixtures of [BMIM]Cl with different organic solvents

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Chinese Journal of Chemical Engineering 2015年第5期23卷 804-811页

作者： Hina Saba Xinjun Zhu Ye Chen Yumei Zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University Department of Material and Engineering Luoyang Institute of Science and Technology

Physical properties including refractive index, density, viscosity and conductivity for binary mixtures of 1-butyl-3-methyl imidazolium chloride([BMIM]Cl) and different organic solvents at 298.15 K have been investigated. Excess molar volumes have been calculated and obtained data has been fitted by the Redlich–Kister equation. The density and refractive index were found to increase with increasing concentration of [BMIM]Cl, however, exceptions do exist as in the case of dimethyl sulfoxide(DMSO)/[BMIM]Cl. For DMSO/[BMIM]Cl, the density decreases with increasing concentration. The addition of different organic solvents was able to disrupt the interactions within mixtures, leading to free mobility of ions. The free mobility of ions has been found to enhance conductivity and decrease viscosity to varying extents in all mixtures studied. It has been observed that solubility parameters,dielectric constants and composition of the solvents used play a vital role in determining the resultant properties.The data obtained will play an important role in understanding the effect of the addition of organic solvents in ILs to enhance their applicability.

关键词：二元混合物有机溶剂 Cl 物理性能测定 DMSO 浓度增加自由离子

Optical coherence tomography of the pulmonary arteries in children with congenital heart diseases:A systematic review

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Pediatric Investigation 2022年第4期6卷 264-270页

作者： Ling Sun Qiuping Jiang yumei Xie Shushui Wang Zhiwei zhang Department of Pediatric Cardiology Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangdong Cardiovascular InstituteGuangdong Provincial Key Laboratory of South China Structural Heart DiseaseGuangzhouGuangdongChina

Importance:Optical coherence tomography(OCT)is a high-resolution intravascular imaging tool and has shown promise for providing real-time quantitative and qualitative descriptions of pulmonary vascular structures in vivo in adult pulmonary hypertension(PH),while not popular in pediatric patients with congenital heart diseases(CHD).Objective:The aim of this review is to summarize all the available evidence on the use of OCT for imaging pulmonary vascular remodeling in pediatric patients.Methods:We conducted the systematic literature resources(Cochran Library database,Medline via PubMed,EMBASE,and Web of Knowledge)from January 2010 to December 2021 and the search terms were“PH”,“child”,“children”,“pediatric”,“OCT”,“CHD”,“pulmonary vessels”,“pulmonary artery wall”.Studies in which OCT was used to image the pulmonary vessels in pediatric patients with CHD were considered for inclusion.Results:Five studies met the inclusion criteria.These five papers discussed the study of OCT in the pulmonary vasculature of different types of CHD,including common simple CHD,complex cyanotic CHD,and Williams-Beuren syndrome.In biventricular anatomy,pulmonary vascular remodeling was primarily reflected by pulmonary intima thickening from two-dimensional OCT.In single-ventricle anatomy,due to the state of hypoxia,the morphology of pulmonary vessels was indirectly reflected by the number and shape of nourishing vessels from three-dimensional OCT.Interpretation:OCT may be an adequate imaging procedure for the demonstration of pulmonary vascular structures and provide additional information in pediatric patients.

关键词： Children Congenital heart diseases Optical coherence tomography Pulmonary hypertension Pulmonary vessels