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Exploiting Multiple Correlations Among Urban Regions for Crowd Flow Prediction

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Journal of Computer Science & Technology 2020年第2期35卷 338-352页

作者： Qiang Zhou Jing-Jing gu Chao Ling wen-Bo Li Yi Zhuang jian Wang College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Crowd flow prediction has become a strategically important task in urban computing,which is the prerequisite for traffic management,urban planning and public ***,due to variousness of crowd flows,multiple hidden correlations among urban regions affect the ***,crowd flows are also influenced by the distribution of Points-of-Interests(POIs),transitional functional zones,environmental climate,and different time slots of the dynamic urban ***,we exploit multiple correlations between urban regions by considering the mentioned factors comprehensively rather than the geographical distance and propose multi-graph convolution gated recurrent units(MGCGRU)for capturing these multiple spatial *** adapting to the dynamic mobile data,we leverage multiple spatial correlations and the temporal dependency to build an urban flow prediction framework that uses only a little recent data as the input but can mine rich internal ***,the framework can mitigate the influence of the instability of data distributions in highly dynamic environments for *** experimental results on two real-world datasets in Shanghai show that our model is superior to state-of-the-art methods for crowd flow prediction.

关键词： crowd flow prediction multi-graph convolutional network multiple correlations mining

Physiological property and yield of the sweet sorghum mutants induced by heavy ion irradiation

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Nuclear Science and Techniques 2016年第4期27卷 83-88页

作者： wen-Ting gu wen-jian Li Rui-Yuan Liu wen-Jie Jin Tao-Li-Wei Yang Xi-Cun Dong Institute of Modern Physics Chinese Academy of Sciences

Soil salinity can limit plant growth and productivity. The cultivation of tolerant varieties is convenient and cost-effective for making good use of the saline *** sweet sorghum plant has a high tolerance for saline alkaline soils. The KF1210-3 and KF1210-4 early-maturity mutants of sweet sorghum were obtained via carbon ion irradiation. The study assesses the productivity of three sweet sorghum cultivars(KF1210-3, KF1210-4, and KFJTCK) which were grown in intermediate(4.6 d S m^(-1)) and high(11.9 d S m^(-1)) soil salinity. The sweet sorghum grown in the soil salinity of 4.6 d S m^(-1)produced 50.00–57.30 %greater fresh weight than that in the soil salinity of11.9 d S m^(-1), while the difference was not as obvious among the dry biomass of the three sweet sorghum cultivars. Moreover, the Brix degree of the sweet sorghum grown in the soil salinity of 11.9 d S m^(-1)was greater than that grown in the soil salinity of 4.6 d S m^(-1). The heavy ion irradiation experiment is of great significance in screening plant mutants, improving environmental conditions, and assessing the productivity. This process, in turn, aids in the understanding of the effects of the biochemical and physiological mechanisms of salt stress.

关键词：早熟突变体甜高粱重离子生理特性辐照诱导土壤含盐量产量土壤盐分

Effect of cross-section shape of rotating chute on particle movement and distribution at the throat of a bell-less top blast furnace

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Particuology 2019年第3期17卷 194-206页

作者： Mingyin Kou jian Xu Shengli Wu Heng Zhou Kai gu Shun Yao Bingjie wen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Department of Metallurgical Engineering College of Materials Science and Engineering Chongqing University Chongqing 400044 China

Rotating chutes are widely used to control the burden distribution and enhance the gas distribution in a blast *** chute cross-section shape has a significant effect on the particle movement and ***,this study developed a three-dimensional model of a blast furnace top with rotating chute using the discrete element *** effect of different chute shapes on the particle movement and radial burden distribution was then *** results showed that the burden stream height at the chute discharge agrees well with the burden stream thickness at the burden surface.A semicircular chute had the largest main striking point,where the chute discharge joins the burden surface,and trapezoidal and rectangular chutes had successively smaller *** semicircular chute helped to obtain a uniform radial size *** trapezoidal chute helped form an aggregated burden stream at low rotating speeds,while the rectangular shape chute achieved this at higher rotating speeds and different chute angles.

关键词： Blast furnace Chute shape Burden size segregation Discrete element method

Discrete numerical modeling of granular materials considering crushability

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Journal of Mountain Science 2017年第4期14卷 758-770页

作者： QIAN jian-gu gu jian-bo gu Xiao-qiang HUANG Mao-song Key Laboratory of Geotechnieal and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

The aim of this study is to numerically investigate the influence of particle breakage on the mechanical behavior of granular materials using a discrete element method(DEM). To enable particle crushing, non-crushable elementary particles are boned together to represents the granular aggregates which can be crushed when the external force exceeds its strength. The flaw of the aggregate was also modeled by randomly distributed void. Single particle crushing tests were carried out to determine the distribution of particle strength. The results of single particle crushing tests illustrate that the simulated single particle fracture strength and pattern agree well with the Weibull's distribution *** oedometer tests, drained monotonic and cyclic triaxial tests were also carried out to investigate the crushing of the aggregates and the associated mechanical behaviors. The effect of confining pressure on the crushing of aggregates and the mechanical behavior was also analyzed. It was found that the peak stress and dilation decrease significantly when particle crushing was *** deformation behavior of the specimen is essentially controlled by two factors: particle rearrangement-induced dilation and particle crushing-induced contraction. The increase of permanent strain and the reduction of dilation were observed during cyclic loading and they tend to reach a stable state after a certain number of cycles. The crushing of aggregate is most significant in the first two cycles. The results also indicated that for the same axial strain the volumetric strain and the bound breakage in the cyclic loading tests are significantly larger than that in the monotonic loading tests,especially at high cyclic stress ratio.

关键词： DEM simulation Granular materials Crushing Monotonic and Cyclic triaxial test

基于机器学习筛选猪活体肌内脂肪含量间接选育和构建预测模型的关键性状

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南京农业大学学报 2025年第1期48卷 161-170页

作者：吴建杨文孟孜查成万吴望军南京农业大学动物科技学院江苏南京210095

[目的]本研究旨在探究猪断奶重、屠宰前活体重、背膘厚等性状因素对猪肌内脂肪(intramuscular fat,IMF)含量的影响,确定影响猪IMF含量的关键性状因素。[方法]以805头皮特兰×[杜洛克×(长白×大白)]四元商品猪群为试验对象,记录性别,测... 详细信息

[目的]本研究旨在探究猪断奶重、屠宰前活体重、背膘厚等性状因素对猪肌内脂肪(intramuscular fat,IMF)含量的影响,确定影响猪IMF含量的关键性状因素。[方法]以805头皮特兰×[杜洛克×(长白×大白)]四元商品猪群为试验对象,记录性别,测定初生重、断奶重、屠宰前活体重和IMF含量等14个性状,然后通过相关性分析从14个性状中初步筛选出影响IMF含量的性状因素,再通过随机森林模型评估各性状因素对IMF含量影响的重要性,进一步通过LASSO回归和逐步回归筛选出影响IMF含量的关键性状因素;在此基础上,利用广义线性模型(generalized linear model,GLM)分析关键性状因素不同水平对IMF含量的影响。[结果]相关性分析结果显示,猪IMF含量与断奶重(r=0.13, P0.05)。胸腰椎结合处背膘厚大于26 mm组的平均IMF含量(2.73%)显著高于其他背膘厚组(P0.05)。[结论]本研究通过机器学习确定了性别、断奶重、屠宰前活体重和胸腰椎结合处背膘厚4个与IMF含量显著相关的活体可测定性状,并发现平均IMF含量随着屠宰前活体重和胸腰椎结合处背膘厚的增加呈明显的上升趋势。

关键词：猪肌内脂肪间接选择模型构建机器学习活体可测定性状

Microstructure and mechanical properties of reaction-bonded B_(4)C–SiC composites

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1828-1835页

作者： Rong-zhen Liu wen-wei gu Yu Yang Yuan Lu Hong-bin Tan jian-feng Yang State Key Laboratory of Materials Processing and Die&Mould Technology School of Material Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Environment-Friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang 621010China

Reaction-bonded B_(4)C–SiC composites are highly promising materials for numerous advanced technological ***,their microstructure evolution mechanism remains ***,B_(4)C–SiC composites were fabricated through the Si-melt infiltration *** influences of the sintering time and the B_(4)C content on the mechanical properties,microstructure,and phase evolution were investigated.X-ray diffraction results showed the presence of SiC,boron silicon,boron silicon carbide,and boron *** electron microscopy results showed that with the increase in the boron carbide content,the Si content decreased and the unreacted B_(4)C amount increased when the sintering temperature reached 1650°C and the sintering time reached 1 *** unreacted B_(4)C diminished with increasing sintering time and temperature when B_(4)C content was lower than 35wt%.Further microstructure analysis showed a transition area between B_(4)C and Si,with the C content marginally higher than in the Si *** indicates that after the silicon infiltration,the diffusion mechanism was the primary sintering mechanism of the *** the diffusion process progressed,the hardness *** maximum values of the Vickers hardness,flexural strength,and fracture toughness of the reaction-bonded B_(4)C–SiC ceramic composite with 12wt%B_(4)C content sintered at 1600°C for 0.5 h were about HV 2400,330 MPa,and 5.2 MPa·m^(0.5),respectively.

关键词： reaction sintering B_(4)C-SiC composites mechanical properties microstructural characterization microstructure evolution mechanism

A Series of Lanthanide-organic Frameworks Constructed by Ln_4(OH)_4 Clusters and Mixed Ligands

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Chinese Journal of Structural Chemistry 2019年第1期38卷 103-108,4页

作者： gu Xiang-Yu JIN Cong-Cong CHENG jian-wen Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical Chemistry Zhejiang Normal University

Three new lanthanide-organic compounds, namely, [Ln_2(OH)_2(oba)(2-pc)_2]n(Ln =Er(1), Ho(2), and Dy(3))(oba = 4,4?-oxybis(benzoate), 2-pc = 2-pyrazinecarboxylic acid) have been obtained under hydrothermal conditions. These compounds are isostructural and exhibit 2 D layered structures by incorporating [Ln_4(μ_3-OH)_4]^(8+) clusters and the mixed linkers of oba and 2-pc. It is interesting that decarboxylation occurred in the ortho position and 2,3-pyrazinedicarboxylic acid was partially transformed into 2-pc under hydrothermal conditions. Compound 3 emits a typical Dy^(3+) emission spectrum. Furthermore, the PXRD, TGA and IR spectra were also studied.

关键词： lanthanide cluster mixed ligands luminescence

Synergistic responses of NHX, AKT1, and SOS1 in the control of Na^+ homeostasis in sweet sorghum mutants induced by ^(12)C^(6+)-ion irradiation

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Nuclear Science and Techniques 2018年第1期29卷 32-38页

作者： wen-Ting gu Li-Bin Zhou Rui-Yuan Liu wen-Jie Jin Ying Qu Xi-Cun Dong wen-jian Li Institute of Modern Physics Chinese Academy of Sciences

Sweet sorghum mutants induced by^(12)C(6+)-ion irradiation were planted under different soil salinity conditions to investigate the mechanisms maintaining the transport and spatial distribution of Na^+. The functions of the synergistic responses of NHX, AKT1, and SOS1 related to Na^+ accumulation were investigated in control(KFJT-CK) sorghum and KF1210-3 and KF1210-4 mutants. The results indicated that the NHX, AKT1, and SOS1 proteins in sweet sorghum are mainly involved in the transport, exclusion, and spatial distribution of Na^+,respectively. In addition to physiological parameters, we also measured the expression levels of NHX, AKT1, and SOS1 genes. The experimental results indicated that 150 m M Na Cl induced marked increases in the transcripts of NHX and SOS1 after 8 and 12 h in the KF1210-3,KF1210-4, and KFJT-CK cultivars. In contrast, however, a decrease in AKT1 was observed. On the basis of our results, we propose a model in which cooperation amongNHX, AKT1, and SOS1 facilitates Na^+ homeostasis in sweet sorghum in response to an increase in salt concentration. Accordingly, study of the regulatory mechanisms in sweet sorghum generated by carbon ion irradiation is essential for the selection of salt-tolerant cultivars.

关键词： 12C6+-ion irradiation Sweet sorghum Salt stress NHX AKT1 SOS1

Entropy majorization, thermal adiabatic theorem, and quantum phase transitions

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Frontiers of physics 2012年第2期7卷 244-251页

作者： Shi-jian gu (1) 1. Department of Physics and Institute of Theoretical Physics The Chinese University of Hong Kong Hong Kong China

Let a general quantum many-body system at a low temperature adiabatically cross through the vicinity of the system＇s quantum critical point. We show that the system＇s temperature is signif- icantly suppressed due to both the entropy majorization theorem in quantum information science and the entropy conservation law in reversible adiabatic processes. We take the one-dimensional transverse-field Ising model and the spinless fermion system as concrete examples to show that the inverse temperature might become divergent around the systems＇ critical points. Since the temper- ature is a measurable quantity in experiments, it can be used, via reversible adiabatic processes at low temperatures, to detect quantum phase transitions in the perspectives of quantum information science and quantum statistical mechanics.

关键词： quantum phase transition entropy majorization