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Data Intelligence 2023年第2期5卷 438-456页

作者： Zhen Peng Yunxiao Zhang Yunchong Wang Tianle tang China University of Geosciences Beijing School of Economics and ManagementBeijing 100038China Beijing Institute of Petrochemical Technology School of Economics and ManagementBeijing 102617China

Air pollution is a major issue related to national economy and people's *** present,the researches on air pollution mostly focus on the pollutant emissions in a specific industry or region as a whole,and is a lack of attention to enterprise pollutant emissions from the micro *** by the amount and time granularity of data from enterprises,enterprise pollutant emissions are stll *** by big data of air pollution emissions of industrial enterprises monitored in Beijing-Tianjin-Hebei,the data mining of enterprises pollution emissions is carried out in the paper,including the association analysis between different features based on grey association,the association mining between different data based on association rule and the outlier detection based on *** results show that:(1)The industries affecting NOx and SO2 mainly are electric power,heat production and supply industry,metal smelting and processing industries in Beijing-Tianjin-Hebei;(2)These districts nearby Hengshui and Shijiazhuang city in Hebei province form strong association rules;(3)The industrial enterprises in Beijing-Tianjin-Hebei are divided into six clusters,of which three categories belong to outliers with excessive emissions of total vOCs,PM and NH3 respectively.

关键词： Air Pollution Emissions of Enterprises Outlier detection based on clustering Association Rule Mining Grey Association Analysis Big data

Last 150-Year Variability in Japanese Anchovy (Engraulisjaponicus) Abundance Based on the Anaerobic Sediments of the Yellow Sea Basin in the Western North Pacific

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Journal of Ocean University of China 2016年第1期15卷 131-136页

作者： HUANG Jiansheng SUN Yao JIA Haibo tang Qisheng College of Ocean and Earth Sciences Xiamen University Xiamen 361005 P. R. China Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 266071 P. R. China

Relatively short historical catch records show that anchovy populations have exhibited large variability over multi-decadal *** order to understand the driving factors(anthropogenic and/or natural) of such variability,it is essential to develop long-term time series of the population prior to the occurrence of notable anthropogenic ***-preserved fish scales in the sediments are regarded as useful indicators reflecting the fluctuations of fish populations over the last *** study aims to validate the anchovy scale deposition rate as a proxy of local anchovy biomass in the Yellow Sea adjoining the western North *** reconstructed results indicated that over the last 150 years,the population size of anchovy in the Yellow Sea has exhibited great fluctuations with periodicity of around 50 years,and the pattern of current recovery and collapse is similar to that of historical *** pattern of large-scale population synchrony with remote ocean basins provides further evidence proving that fish population dynamics are strongly affected by global and basin-scale oceanic/climatic variability.

关键词： fish scales record anchovy the central South Yellow Sea population dynamic

A Variational Binary Level Set Method for Structural Topology Optimization

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Communications in Computational Physics 2013年第5期13卷 1292-1308页

作者： Xiaoxia Dai Peipei tang Xiaoliang Cheng Minghui Wu School of Computing Science Zhejiang University City CollegeHangzhouP.R.China Department of Mathematics Zhejiang UniversityHangzhouP.R.China

This paper proposes a variational binary level set method for shape and topology optimization of ***,a topology optimization problem is presented based on the level set method and an algorithm based on binary level set method is proposed to solve such *** the difficulties of coordination between the various parameters and efficient implementation of the proposed method,we present a fast algorithm by reducing several parameters to only one parameter,which would substantially reduce the complexity of computation and make it easily and quickly to get the optimal *** algorithm we constructed does not need to re-initialize and can produce many new holes ***,the fast algorithm allows us to avoid the update of Lagrange multiplier and easily deal with constraints,such as piecewise constant,volume and length of the ***,we show several optimum design examples to confirm the validity and efficiency of our method.

关键词： Structural optimization binary level set method finite element method

Particle size distribution of bed materials in the sandy river bed of alluvial rivers

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International Journal of Sediment Research 2017年第3期32卷 331-339页

作者： Luohao Zhang Hongwu Zhang Hongwu tang Chensu Zhao College of Water Conservancy and Hydropower Engineering Hohai University State Key Laboratory of Hydroscience and Engineering Tsinghua University School of Civil and Environment Engineering University of Science and Technology Beijing

The particle size distribution of bed materials in the sandy river bed of alluvial rivers is important in the study of topics such as friction, river bed evolution, erosion, and siltation. It also can reflect the dependency relation between river bed sediment and flow intensity. In this paper, the critical pattern of sediment movement in the near-wall region of a sandy river bed was analyzed. According to the principle of momentum balance, the critical settling-rising condition of bed material in a sandy river bed was found to be instantaneous turbulent velocity equal to 2.7 times the sediment settling velocity in quiescent water. Based on a vertical instantaneous turbulent velocity with a Gaussian distribution, a theoretical relation for calculating the particle size distribution of bed materials in a sandy river bed without pre-known characteristic grain sizes was developed by solving a stochastic equation. The formula is verified using measured data, and the results show that the proposed formula was in accordance with the measured data. This study has theoretical significance and practical value for determining the bed material particle size distribution of the sandy bed of alluvial rivers.

关键词： Particle size distribution Bed material Turbulence Momentum Sandy river bed

Asymmetric competition for light varies across functional groups

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Journal of Plant Ecology 2017年第1期10卷 74-80页

作者： Qiang Guo Xiulian Chi Zongqiang Xie Zhiyao tang Department of Ecology College of Urban and Environmental Sciences and Key Laboratory of Earth Surface Processes of the Ministry of EducationPeking University5 Yiheyuan RoadBeijing 100871China National Resource Center for Chinese Materia Medica China Academy of Chinese Medical SciencesBeijing 100700China 3 State Key Lab oratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesNo.20 NanxincunXiangshanBeijing 100093China

Aims Asymmetric competition for light may depress the growth rates(GRs)to different extents for different-sized tree *** responses of different functional groups to light availability result that tree individuals of different functional groups may experience different competition intensities,*** and deciduous species grow faster and demand more light than understory and evergreen *** this study,we estimated the effects of asymmetric competition for light using individual GRs and explored the effects of asymmetric competition on growth among different functional groups(*** *** species and deciduous *** species).Methods We measured growth in circumference to determine the radial increments of a total of 2233 stems with diameter at breast height≥5.0 cm in a permanent plot(140×80 m^(2))located in a typical evergreen and deciduous broadleaved mixed forest on Mt Shennongjia,*** of the measurements were carried out at~6-month intervals every April and October from 2012 to 2014,and biomass of each individual was calculated based on its diameter and species-specific *** then calculated GRs of annual biomass growth(growth between October and the next October).Considering the hypothesis that asymmetric competition for light among trees of different sizes may result in a steeper allometric growth curve with increasing tree size,we further divided the sampled trees into different subsets according to their height,at intervals of 1 m,and then fitted the scaling relationship between the logarithm of the biomass GR(logGR)and the logarithm of diameter(logD)for each height class using standardized major axis ***,we used simple linear regression to test whether the scaling exponent was related to tree *** above analyses were conducted for the annual growth of all tree species,canopy species,understory *** species and deciduous *** *** findings We observed a conca

关键词： asymmetric competition tree height metabolic scaling theory tree growth functional group

Cis-regulatory change and expression divergence between duplicate genes formed by genome duplication of Arabidopsis thaliana

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Chinese Science Bulletin 2010年第22期55卷 2359-2365页

作者： CHEN KeNian ZHANG YanBin tang Tian SHI SuHua State Key Laboratory of Biocontrol School of Life Sciences Sun Yat-Sen (Zhongshan) University Guangzhou 510275 China Department of Biotechnology Guangzhou Medical College Guangzhou 510182 China College of Computer Science Hangzhou Dianzi University Hangzhou 310018 China

As an index of functional divergence, expression divergence between duplicate gene copies has been observed and correlated with protein coding sequence divergence and bias in gene functional classes. However, the changes in the cis-regulatory region of the duplicate genes which is thought to have important role in expression divergence, has not been explored on the genome-wide scale. We analyzed functional genomics data for a large number of duplicated gene pairs formed by ancient polyploidy events in Arabidopsis thaliana. The divergence in cis-regulatory regions between two copies is positively correlated with the magnitude difference of expression. Moreover, we find that highly expressed duplicate gene pairs have a more diverged cis-regulatory region than weakly expressed gene pairs. We also show that the correlation between expression functional constraint and protein functional constraint is different in old and young duplicate pairs. Our results suggest that cis-regulatory sequence divergence contributes to the expression divergence of duplicate genes formed by genome-wide duplication. Cis-regulatory region diverges faster in highly expressed duplicate pairs. The diversify selection strengths that act on cis-regulatory region and protein coding region are negatively correlated in young duplicate pairs under expression constraint.

关键词：全基因组拟南芥独联体分歧复形监管基因表达差异蛋白质编码区

Study of the continuum removal method for the Moon Mineralogy Mapper(M^3) and its application to Mare Humorum and Mare Nubium

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Research in Astronomy and Astrophysics 2016年第7期16卷 133-142页

作者： Xun-Yu Zhang Zi-Yuan Ouyang Xiao-Meng Zhang Yuan Chen Xiao tang Ao-Ao Xu Ze-Sheng tang Yun-Zhao Wu Space Science Institute Macao University of Science and Technology Macao 00853 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210023 China Key Laboratory of Planetary Sciences Chinese Academy of Sciences Nanjing 210008 China

The absorption band center of visible and near infrared reflectance spectra is a key spectral parameter for lunar mineralogical studies, especially for the mafic minerals（olivine and pyroxene） of mare basalts, which have two obvious absorption bands at 1000 nm（Band I） and 2000 nm（Band II）. Removal of the continuum from spectra, which was developed by Clark and Roush and used to isolate the particular absorption feature, is necessary to estimate this parameter. The Moon Mineralogy Mapper（M3） data are widely used for lunar mineral identification. However, M3 data show a residual thermal effect, which interferes with the continuum removal, and systematic differences exist among optical data taken during different optical periods. This study investigated a suitable continuum removal method and compared the difference between two sets of M3 data taken during different optical periods, Optical Period 1B（OP1B）and Optical Period 2A（OP2A）. Two programs for continuum removal are reported in this paper. Generally,a program respectively constructs two straight lines across Band I and Band II to remove the continuum,which is recommended for locating band centers, because it can find the same Band I center with different right endpoints. The optimal right endpoint for continuum removal is mainly dominated by two optical period data at approximately 2480 and 2560 nm for OP1 B and OP2 A data, respectively. The band center values derived from OP1 B data are smaller than those derived from OP2 A data in Band I but larger in Band II, especially for the spectra using longer right endpoints（〉2600 nm）. This may be due to the spectral slopes of OP1 B data being steeper than those of OP2 A data in Band I but gentler in Band II. These results were applied to Mare Humorum and Mare Nubium, and the measurements were found to mainly vary from intermediate- to high-Ca pyroxene.

关键词： techniques spectroscopic methods data analysis instrumentation spectrographs

SHRIMP zircon U-Pb dating for two episodes of migmatization in the Dabie orogen

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Chinese Science Bulletin 2007年第13期52卷 1836-1842页

作者： WU YuanBao tang Jun ZHANG ShaoBing ZHAO ZiFu State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Beijing SHRIMP Center Chinese Academy of Geological Sciences Beijing 100037 China

Zircon CL imaging and SHRIMP U-Pb dating were carried out for migmatite in the Dabie orogen. Zircons from the Manshuihe migmatite show clear core-rim structures. The cores display sector or weak zoning and low Th/U ratios of 0.01 to 0.17, indicating their precipitation from metamorphic fluid. They yield a weighted mean age of 137±5 Ma. By contrast, the rims exhibit planar or nebulous zoning with relatively high Th/U ratios of 0.35 to 0.69, suggesting their growth from metamorphic melt. They give a weighted mean age of 124±2 Ma. Zircons from the Fenghuangguan migmatite also display core-rim structures. The cores are weakly oscillatory zoned or unzoned with high Th/U ratios of 0.21 to 3.03, representing inherited zircons of magmatic origin that experienced different degrees of solid-state recrystallization. SHRIMP U-Pb analyses obtain that its protolith was emplaced at 768±12 Ma, consistent with middle Neoproterozoic ages for protoliths of most UHP metaigneous rocks in the Dabie-Sulu orogenic belt. By contrast, the rims do not show significant zoning and have very low Th/U ratios of 0.01 to 0.09, typical of zircon crystallized from metamorphic fluid. They yield a weighted 206Pb/238U age of 137±4 Ma. Taking the two case dates together, it appears that there are two episodes of zircon growth and thus migmati-tization at 137±2 Ma and 124±2 Ma, respectively, due to metamorphic dehydration and partial melting. The appearance of metamorphic dehydration corresponds to the beginning of tectonic extension thus to the tectonic switch from crustal compression to extension in the Dabie orogen. On the other hand, the partial melting is responsible for the extensional climax, resulting in formation of coeval migmatite, granitoid and granulite. They share the common protolith, the collision-thickened continental crust of mid-Neoproterozoic ages.

关键词：混合岩锆石脱水处理溶解作用

TaVNS reduces inflammatory responses in a L-NAME-induced rat model of pre-eclampsia

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BIOCELL 2021年第5期45卷 1231-1240页

作者： LINMEI ZHENG RONG tang LEI SHI ZHONGYI ZHOU Department of Obstetrics Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou570100China Department of General Surgery Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou570100China Department of ICU Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou570100China

Pre-eclampsia is characterized by an excessive maternal inflammatory *** cholinergic antiinflammatory pathway(CAP)has been shown as the efferent arm of a vagal reflex with the potential to limit inflammatory ***,in this study,the CAP regulation through the nervous vagal stimulation(VNS)reduced the severity of NG-nitro-L-arginine methyl ester(L-NAME)-induced pre-eclampsia was determined in a rat *** were given 125 mg/kg/day of L-NAME via subcutaneous injection on gestational day(GD)10–*** addition,the rats were treated by active or sham electrical stimulation once a day during GD 13–*** blood pressure(SBP),urinary albumin,and pregnancy outcomes were documented for each *** average fetal weights and crown-rump length(CRL)as well as the placental weights of rats in both control and experimental groups were recorded onthe 13th day,16th day and 20th day of ***,placentas were collected from the rats on GD20 to measure the level of *** addition,qRT-PCR and Western blot analysis were used to detect the mRNA and protein expression ofα7 nicotinic acetylcholine receptor(α7nAChR)and nuclear factor-κB(NF-κB),*** assays were also carried out to determine the location and level ofα7nAChR and NF-κB in *** regulation through the transcutaneous auricular nerve stimulation alleviated the clinical symptoms in the rats after L-NAME induction,including hypertension,proteinuria,fetal growth retardation and fetal *** addition,TaVNS also increasedα7nAChR expression,reduced NF-κB p65 expression,and reversed LNAME-induced proinflammatory cytokines in the placenta tissues,including tumor necrosis factor-alpha(TNF-α),high mobility group box 1(HMGB-1)and interleukin-6(IL-6).The findings of this study showed that TaVNS might be used as a promising tool to attenuate pre-eclampsia-like *** addition,the protective effect of TaVNS was associated with the improvement ofα7nAChR

关键词： Pre-eclampsia Cholinergic anti-inflammatory pathway TaVNS Inflammation

Coordination Control of Greenhouse Environmental Factors

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International Journal of Automation and computing 2011年第2期8卷 147-153页

作者： Feng Chen Yong-Ning tang Ming-Yu Shen Department of Automation University of Science and Technology of China Hefei 230027 PRC School of Information Technology Illinois State University Normal IL 61790 USA School of Computer and Information Science Hefei University of Technology Hefei 230066 PRC

Optimal control of greenhouse climate is one of the key techniques in digital *** climate,a nonlinear and uncertain system,consists of several major environmental factors such as temperature,humidity,light intensity,and CO 2 *** to the complex coupled correlations,it is a challenge to achieve coordination control of greenhouse environmental *** paper proposes a model-free coordination control approach for greenhouse environmental factors based on *** control policy is found through systematic interaction with the dynamic environment to achieve optimal control for greenhouse climate with the control cost *** order to decrease systematic trial-and-error risk and reduce the computational complexity in Q-learning algorithm,case-based reasoning （CBR） is seamlessly incorporated into the Q-learning *** experimental results demonstrate that this approach is practical,highly effective and efficient.

关键词： Q-learning case-based reasoning (CBR) greenhouse environmental factors coordination control coupled correlation trial-and-error.