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Spatiotem.oral characterization and regional contributions of o3 and No2:An investigation of two years of monitoring data in Henan,China

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Journal of Environmental Sciences 2020年第4期32卷 29-40页

作者： Shijie Yu Shasha Yin Ruiqin Zhang lingling Wang Fangcheng Su Yixiang Zhang Jian Yang Research Institute of Environmental Science College of Chemistry and Molecular EngineeringZhengzhou UniversityZhengzhou450001China Henan Environment monitoring Centre Zhengzhou450004China

To investigate the characteristics of ground level ozone(o3)for Henan Province,the ambient air quality monitoring data of 2015 and 2016 were *** result showed that the 8 h-max-o3 concentrations displayed a distinct seasonality,where the maximum and minimum values,averaging 140.41,54.19μg/m3,occurred in summer and winter,*** is a significant correlation between meteorological factors and o3 *** Voronoi neighborhood averaging analysis indic ated that o3,temperature,and ultraviolet radiation in Henan province were decreased from northwest to southeast,while relative humidity and precipitation displayed the opposite *** meteorological factors,the chemical processes play an essential role in ozone *** of No,No2 and o3 form a closed system,and the partitioning point of the oX-com.onent(o3+No2)was at 40 and 80μg/m3 for nitrogen oxide(Nox)in winter and summer,respectively,with No2 dominating at higher Nox pollution and o3 being the m ajor com.onent at lower *** relationship between oxidant(oX=o3+No2)and Nox concentrations were evaluated to understand the regional and local contribution of *** showed that high regional contribution occurred in the spring,whereas the highest local contribution lead to the summer peak of o3 observed in *** present study reveals im.ortant environment impacts from the photochemical process and the meteorological conditions in the region with better understanding on the o3 characterization.

关键词： Ground-level ozone meteorological parameter Photochemical oxidant Voronoi neighborhood averaging(VNA) Seasonal variation

Towards characterizing bug fixes through dependency-level changes in Apache Java open source projects

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Science China(Information Sciences) 2022年第7期65卷 102-120页

作者： Di CUI lingling FAN Sen CHEN Yuanfang CAI Qinghua ZHENG Yang LIU Ting LIU School of Computer Science and Technology Xi'an Jiaotong University College of Cyber Science Nankai University College of Intelligence and Computing Tianjin University Department of Computer Science Drexel University School of Computer Science and Engineering Nanyang Technological University School of Cyber Science and Engineering Xi'an Jiaotong University

The complexity and diversity of bug fixes require developers to understand bug fixes from multiple perspectives in addition to fine-grained code changes. The dependencies among files in a software system are an im.ortant dimension to inform software quality. Recent studies have revealed that most bug-prone files are always architecturally connected with dependencies, and as one of the best practices in the industry,changes in dependencies should be avoided or carefully made during bug fixing. Hence, in this paper, we take the first attempt to understand bug fixes from the dependencies perspective, which can complement existing code change perspectives. Based on this new perspective, we conducted a systematic and comprehensive study on bug fixes collected from 157 Apache open source projects, involving 140456 bug reports and182621 bug fixes in total. our study results show that a relatively high proportion of bug fixes(30%) introduce dependency-level changes when fixing the corresponding 33% bugs. The bugs, whose fixes introduce dependency-level changes, have a strong correlation with high priority, large fixing churn, long fixing time,frequent bug reopening, and bug inducing. more im.ortantly, patched files with dependency-level changes in their fixes, consume much more maintenance costs compared with those without these changes. We further summarized three representative patch patterns to explain the reasons for the increasing costs. our study unveils useful findings based on qualitative and quantitative analysis and also provides new insights that might benefit existing bug prediction techniques. We release a large set of benchmarks and also implement a prototype tool to automatically detect dependency-level changes from bug fixes, which can warn developers and remind them to design a better fix.

关键词： empirical software engineering Empirical Software Engineering software maintenance Software maintenance Software Evolution software evolution Software Architecture software architecture software design Software Design

CLDASSD:Reconstructing Fine Textures of the Temperature Field Using Super-Resolution Technology

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Advances in Atmospheric Sciences 2022年第1期39卷 117-130页

作者： Ruian TIE Chunxiang SHI Gang WAN Xingjie HU Lihua KANG lingling GE Institute of Aerospace Information Space Engineering UniversityBeijing 101400China National meteorological Information Center China Meteorological AdministrationBeijing 100081China

Before 2008,the number of surface observation stations in China was ***,the surface observation data were too sparse to effectively support the High-resolution China meteorological Administration’s Land Assimilation System(HRCLDAS)which ultimately inhibited the output of high-resolution and high-quality gridded *** paper proposes a statistical downscaling model based on a deep learning algorithm in super-resolution to research the above ***,we take temperature as an *** model is used to downscale the 0.0625°×0.0625°,2-m temperature data from the China meteorological Administration’s Land Data Assimilation System(CLDAS)to 0.01°×0.01°,named *** performed quality control on the paired data from CLDAS and HRCLDAS,using data from 2018 and *** was trained on the data from 31 march 2018 to 28 February 2019,and then tested with the remaining ***,extensive experiments were conducted in the Beijing-Tianjin-Hebei region which features complex and diverse *** the HRCLDAS product and surface observation data as the"true values"and comparing them with the results of bilinear interpolation,especially in complex terrain such as mountains,the root mean square error(RmSE)of the CLDASSD output can be reduced by approximately 0.1℃,and its structural similarity(SSIm)was approximately 0.2 *** can estimate detailed textures,in terms of spatial distribution,with greater accuracy than bilinear interpolation and other sub-models and can perform the expected downscaling tasks.

关键词： statistical downscaling deep learning temperature field high-resolution reconstruction

milk selenium content and speciation in response to supranutritional selenium yeast supplementation in cows

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Animal Nutrition 2021年第4期7卷 1087-1094页

作者： lingling Sun Gentao Liu Dongmei Xu Zhaohai Wu Lu ma Sanz-Fernandez m.Victoria Lance H.Baumgard Dengpan Bu State Key Laboratory of Animal Nutrition Institute of Animal Sciences of Chinese Academy of Agricultural SciencesBeijing 100193China Comparative Physiology Group Subdireccion General de Investigacion y Tecnologia(SGIT)Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria(INIA)Madrid 28040Spain Department of Animal Science Iowa State UniversityAmes 50014USA CAAS-ICRAF Joint Lab on Agroforestry and Sustainable Animal Husbandry Beijing 100193China Hunan Co-Innovation Center of Animal Production Safety CICAPSChangshaHunan 410128China

The effects of selenium(Se)yeast supplementation on performance,blood biochemical and antioxidant parameters,and milk Se content and speciation were ***-six mid-lactation Holstein dairy cows were randomly assigned to 1 of 3 treatments:1)control(basal diet containing Se at 0.11 mg/kg Dm),2)basal diet+0.5 mg supplemental Se/kg Dm(SY-0.5),and 3)basal diet+5 mg supplemental Se/kg Dm(SY-5).Selenium was supplemented as Se *** trial consisted of a 1-week pretrial period and an 8-week experimental *** somatic cell score decreased with SY-5 supplementation(Pother performance parameters were not affected(P>0.05).The serum Se concentration increased with the increasing levels of Se yeast supplementation(Powever,blood biochemical parameters showed few treatment *** antioxidant capacity of dairy cows was improved with Se yeast supplementation reflected in increased serum glutathione peroxidase activity(Potal antioxidant capacity(P=0.08),and decreased malondialdehyde concentration(Pmilk total Se concentration increased with Se dose(Po,the selenomethionine concentration increased with Se dose from 13.0±0.7 pg/kg in control to 33.1±2.1 pg/kg in SY-0.5 and 530.4±17.5 pg/kg in SY-5 cows(Pmilarly,selenocystine concentration increased from 15.6±0.9μg/kg in control and 18.9±1.1 pg/kg in SY-0.5 to 22.2±1.5 pg/kg in SY-5 cows(Ponclusion,Se yeast is a good organic Se source to produce Se-enriched cow milk with increased Se species including selenomethionine and *** results can provide useful information on milk Se species when a high dose Se yeast was supplemented in the cow diet.

关键词： Dairy cow Selenium yeast Selenium speciation milk performance

Statistical analysis of mesoscale eddy propagation velocity in the South China Sea deep basin

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Acta oceanologica Sinica 2020年第11期39卷 91-102页

作者： Runqi Huang lingling Xie Quanan Zheng mingming Li Peng Bai Keyi Tan Laboratory of Coastal ocean Variation and Disaster Prediction College of Ocean and MeteorologyGuangdong Ocean UniversityZhanjiang 524088China marine Resources Big Data Center of South China Sea Southern Marine Science and Engineering Guangdong Laboratory(Zhanjiang)Zhanjiang 524025China Department of Atmospheric and oceanic Science University of MarylandCollege ParkMaryland 20742USA

Using mesoscale eddy trajectory product derived from satellite altimetry data from 1993 to 2017,this study analyzes the statistical characteristics of spatiotem.oral distribution of mesoscale eddy propagation velocities(C)in the South China Sea(SCS)deep basin with depths>1000 ***,the zonal propagation velocities(cx)are westwards in the whole basin,and the meridional velocities(cy)are southwards in the northwestern basin,and northwards in the southeastern *** variation of cy with longitude is consistent with that of the background meridional currents with correlation coefficient R2 of 0.96,while the variation of cx is related both to the background zonal currents andβ*** propagation velocities characterize significant seasonality with the minimum magnitude occurring in summer and the maximum in winter for cx and ***,larger values of cx and cy mostly occurred in La Ni?a years in the negative phase of the Pacific Decadal oscillation(PDo).mesoscale eddies move fast at the beginning and end of their life span,i.e.,at their growth and dissipation periods,and slowly during their stable"midlife"*** trend is negatively correlated with the rotating tangential velocity with R2 of–*** with extreme propagation velocities are defined,which are slower(faster)than 1.5 cm/s(15.4 cm/s)and take 1.5%(1.9%)of the total *** extremely slow-moving(fastmoving)eddies tend to appear in the middle(on the edge)of the basin,and mostly occur in summer(winter).The mechanism analysis reveals that the spatiotem.oral distributions of the propagation velocities of mesoscale eddies in the SCS are modulated by the basin-scale background circulation.

关键词： South China Sea mesoscale eddies eddy propagation velocity variation in life span eddies with abnormal speeds

CFD-DEm simulation of fluid-solid flow of a tapered column separation bed

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International Journal of mining Science and Technology 2015年第5期25卷 855-859页

作者： Duan Chenlong Sheng Cheng Wu lingling Zhao Yuemin He Jinfeng School of Chemical Engineering and Technology China University of Mining & Technology

Research on recycling waste Printed Circuit Boards(PCB) is at the forefront of preventing environmental pollution and finding ways to recycle *** Tapered Column Separation Bed(TCSB) is invented aiming at disposing the problem that fine particles of waste printed circuit boards cannot be separated efficiently so as to obtain further insight about the underlying mechanisms and demonstrate the separation feasibility in the tapered column separation *** this work,a Computational Fluid Dynamics(CFD) coupled with Discrete Element method(DEm) model for two-phase flow has been extended to simulate the fluid-solid flow in the tapered column separation *** validity is demonstrated by its successful capturing the key features of particles' flow pattern,velocity,the pressure distribution,the axial position with time and axial force for particles with different *** results show that the plastic particles and resin particles become overflow,while copper particles,iron particles and aluminum particles successively become underflow,with a discharge water flow rate of 1 m^3/h,an obliquity of 30°.The simulated results agree reasonably well with the experimental *** this equipment to separate waste PCBs is feasible,theoretically.

关键词： Tapered column separation bed Waste printed circuit boards Computational fluid dynamics Discrete element method Fluid-solid flow

Numerical modeling on strain energy evolution in rock system interaction with energy-absorbing prop and rock bolt

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International Journal of mining Science and Technology 2023年第10期33卷 1273-1288页

作者： Yang Hao Chunhui Liu Yu Wu Hai Pu Yanlong Chen lingling Shen Guichen Li State Key Laboratory of Intelligent Construction and Healthy operation and maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China School of mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China School of mines China University of Mining and TechnologyXuzhou 221116China

The interaction mechanism between coal and rock masses with supporting materials is significant in roadway control, especially in deep underground mining situations where dynamic hazards frequently happened due to high geo-stress and strong disturbed effects. This paper is to investigate the strain energy evolution in the interaction between coal and rock masses with self-designed energy-absorbing props and rock bolts by numerical modeling with the finite difference method. The interaction between rock and rock bolt/prop is accomplished by the cables element and the interface between the inner and outer props. Roadway excavation and coal extraction conditions in deep mining are numerically employed to investigate deformation, plastic zone ranges, strain energy input, accumulation, dissipation,and release. The effect on strain energy input, accumulation, dissipation, and release with rock deformation, and the plastic zone is addressed. A ratio of strain energy accumulation, dissipation, and release with energy input a, β, γ is to assess the dynamic hazards. The effects on roadway excavation and coal extraction steps of a, β, γ are discussed. The results show that:(1) In deep high geo-stress roadways, the energyabsorbing support system plays a dual role in resisting deformation and reducing the scope of plastic zones in surrounding rock, as well as absorbing energy release in the surrounding rock, especially in the coal extraction state to mitigate disturbed effects.(2) The strain energy input, accumulation is dependent on roadway deformation, the strain energy dissipation is relied on plastic zone area and disturbed effects, and strain energy release density is the difference among the three. The function of energyabsorbing rock bolts and props play a key role to mitigate strain energy release density and amount, especially in coal extraction condition, with a peak density value from 4×10^(4) to 1×10^(4)J/m^(3), and amount value from 3.57×10^(8) to 1.90×10^(6)J.(3) W

关键词： Strain energy Coal and rock mass Energy-absorbing prop and rock bolt Strain energy evolution

200-nm long Tio_2 nanorod arrays for efficient solid-state Pb S quantum dot-sensitized solar cellsR

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Journal of Energy Chemistry 2018年第4期27卷 1214-1218页

作者： Zhengguo Zhang Chengwu Shi Kai Lv Chengfeng ma Guannan Xiao lingling Ni School of Chemistry and Chemical Engineering Hefei University of TechnologyHefei 230009AnhuiChina School of Chemistry and Chemical Engineering Beifang University of NationalitiesYinchuan 750021NingxiaChina

To ensure the infiltration of spiro-omeTAD into the quantum dot-sensitized photoanode and to consider the limit of the hole diffusion length in the spiro-omeTAD layer, a rutile Tio2 nanorod array with a length of 200 nm, a diameter of 20 nm and an areal density of 720 ram 2 was successfully prepared using a hydrothermal method with an aqueous-grown solution of 38 mm titanium isopropoxide and 6 m hydrochloric acid at 170 ℃ for 75 min. PbS quantum dots were deposited by a spin coating-assisted successive ionic layer adsorption and reaction （spin-SILAR）, and all solid-state PbS quantum dot-sensitized Tio2 nanorod array solar cells were fabricated using spiro-omeTAD as electrolytes. The results revealed that the average crystal size of PbS quantum dots was -78 nm using Pb（No3）2 as the lead source and remain unchanged with the increase of the number of spin-SILAR cycles. The all solid-state PbS quantum dot-sensitized Tio2 nanorod array solar cells with spin-SILAR cycle numbers of 20, 30 and 40 achieved the photoelectric conversion efficiencies of 3.74%, 4.12% and 3.11%, respectively, under Am 1.5 G illumination （100 mW/cm2）.

关键词： Tio2 nanomd array PbS quantum dot Spiro-omeTAD All solid-state sensitized solar cell

Fabric changes induced by super-absorbent polymer on cementelime stabilized excavated clayey soil

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Journal of Rock mechanics and Geotechnical Engineering 2021年第5期13卷 1124-1135页

作者： Xia Bian lingling Zeng Xiaozhao Li Xiusong Shi Shuming Zhou Fuqing Li Key Laboratory of ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China College of Civil Engineering and Architecture Zhejiang University of TechnologyHanzhou310014China State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou221116China Beijing Urban Construction Design and Development Group Co. Ltd.Beijing100037China Seazen Holdings Co. Ltd.Shanghai200062China

This paper studies the microstructure variation induced by super-absorbent polymer(SAP)to understand the mechanism.of macroscopic strength improvement of stabilized *** fabric changes of cement elime stabilized soil were analyzed with respect to the variation of SAP content,water content,lime content and curing time,using mercury intrusion porosimetry(mIP)*** can be observed that the delimitation pore diameter between inter-and intra-aggregate pores was 0.2 mm for the studied soil,determined through the intrusion/extrusion *** results showed that fabric in both inter-and intra-aggregate pores varied significantly with SAP content,lime content,water content and curing *** main changes in fabric due to SAP are identified as:(1)an increase in intra-aggregate pores(mm)due to the closer soilecementelime cluster space at higher SAP content;and(2)a decrease in inter-aggregate pores represented by a reduction in small-pores(0.2e2 mm)due to the lower pore volume of soil mixture after water absorption by SAP,and a slight increase in large-pores(>2 mm)due to the shrinkage of SAP particle during the freezeedry process of mIP ***,the strength gain due to SAP for cementelime stabilized soil was mainly due to a denser fabric with less interaggregate *** cementitious products gradually developed over time,leading to an increase in intra-aggregate pores with an increasing proportion of micro-pores(0.006e0.2 mm).meanwhile,the inter-aggregate pores were filled by cementitious products,resulting in a decrease in total void ***,the strength development over time is attributable to the enhancement of cementation bonding and the refinement of fabric due to the increasing cementitious com.ounds.

关键词： Fabric Soil stabilization microstructure Super-absorbent polymer(SAP)