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Elevated CO_(2) increases soil redox potential by promoting root radial oxygen loss in paddy field

Journal of Environmental Sciences 2024年第2期136卷 11-20页

作者： Jie Li Han Zhang Wenyi Xie Cheng Liu Xiaoyu Liu Xuhui Zhang Lianqing Li Genxing Pan Institute of Resource Ecosystem and Environment of AgricultureNanjing Agricultural UniversityNanjing 210095China College of Agriculture Nanjing Agricultural UniversityNanjing 210095China

Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil nutrients.Whereas its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warming has seldom been investigated.Thus,in this study,a field experiment was used to elucidate the effect of elevated CO_(2) concentration and warming on soil Eh,redox-sensitive elements and root radial oxygen loss(ROL).We hypothesized elevated CO_(2) and warming could alter soil Eh by promoting or inhibiting ROL.We found that soil Eh in the rhizosphere was significantly higher than that of non-rhizosphere.Elevated CO_(2) enhanced soil Eh by 11.5%,which corresponded to a significant decrease in soil Fe^(2+)and Mn^(2+)concentration.Under elevated CO_(2),the concentration of Fe^(2+)and Mn^(2+)decreased by 14.7%and 13.7%,respectively.We also found that elevated CO_(2) altered rice root aerenchyma structure and promoted rice root ROL.Under elevated CO_(2),rice root ROL increased by 79.5%and 112.2%for Yangdao 6 and Changyou 5,respectively.Warming had no effect on soil Eh and rice root ROL.While warming increased the concentration of Mn^(2+)and SO_(4)^(2-)by 4.9%and 19.3%,respectively.There was a significant interaction between elevated CO_(2) and warming on Fe^(2+)and Mn^(2+).Under elevated CO_(2),warming had no effect on the concentration of Fe^(2+)but decreased Mn^(2+)concentration significantly.Our study demonstrated that elevated atmospheric CO_(2) in the future could increase soil Eh by promoting rice root ROL,which will alter some soil nutrients'availability,such as Fe^(2+)and Mn^(2+).

关键词： Atmospheric CO_(2)enrichment Global warming Soil redox potential face Rice root aerenchyma

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Faster Region Convolutional Neural Network(FRCNN)Based Facial Emotion Recognition

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Computers, Materials & Continua 2024年第5期79卷 2427-2448页

作者： J.Sheril Angel A.Diana Andrushia TMary Neebha Oussama Accouche Louai Saker N.Anand Department of Electronics and Communication Engineering Karunya Institute of Technology and SciencesCoimbatore641114India College of Engineering and Technology American University of the Middle EastEgaila54200Kuwait Department of Civil Engineering Karunya Institute of Technology and SciencesCoimbatore641114India

Facial emotion recognition(FER)has become a focal point of research due to its widespread applications,ranging from human-computer interaction to affective computing.While traditional FER techniques have relied on handcrafted features and classification models trained on image or video datasets,recent strides in artificial intelligence and deep learning(DL)have ushered in more sophisticated approaches.The research aims to develop a FER system using a Faster Region Convolutional Neural Network(FRCNN)and design a specialized FRCNN architecture tailored for facial emotion recognition,leveraging its ability to capture spatial hierarchies within localized regions of facial features.The proposed work enhances the accuracy and efficiency of facial emotion recognition.The proposed work comprises twomajor key components:Inception V3-based feature extraction and FRCNN-based emotion categorization.Extensive experimentation on Kaggle datasets validates the effectiveness of the proposed strategy,showcasing the FRCNN approach’s resilience and accuracy in identifying and categorizing facial expressions.The model’s overall performance metrics are compelling,with an accuracy of 98.4%,precision of 97.2%,and recall of 96.31%.This work introduces a perceptive deep learning-based FER method,contributing to the evolving landscape of emotion recognition technologies.The high accuracy and resilience demonstrated by the FRCNN approach underscore its potential for real-world applications.This research advances the field of FER and presents a compelling case for the practicality and efficacy of deep learning models in automating the understanding of facial emotions.

关键词： Facial emotions FRCNN deep learning emotion recognition face CNN

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长期自由大气CO_(2)富集下稻田土壤有机碳分布结构与红外光谱特征研究

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扬州大学学报（农业与生命科学版） 2024年第2期45卷 1-9页

作者：宋娴张飞繁马莹莹尹微琴许美玲王小治徐乔扬州大学环境科学与工程学院江苏扬州225127 内蒙古工业大学矿业学院呼和浩特010051 扬州大学农业农村部耕地质量监测与评价重点实验室江苏扬州225127

为探究野外自由大气CO_(2)浓度长期升高对不同深度农田土壤碳、氮含量和分布的影响,依托中国face(Free-air CO_(2) enrichment)系统平台,以15年试验区的土壤为研究样本,分析不同深度土壤总碳和全氮含量的变化,基于湿筛法区分颗粒态有机... 详细信息

为探究野外自由大气CO_(2)浓度长期升高对不同深度农田土壤碳、氮含量和分布的影响,依托中国face(Free-air CO_(2) enrichment)系统平台,以15年试验区的土壤为研究样本,分析不同深度土壤总碳和全氮含量的变化,基于湿筛法区分颗粒态有机质(POM)和矿质结合态有机质(MAOM),并通过傅里叶红外光谱法研究不同深度土壤有机碳官能团的变化。结果表明:face处理有提高0~15、15~30 cm土壤总碳、全氮含量的趋势,其中0~15 cm土壤总碳、全氮含量较对照分别增加12.52%和14.32%,而15~30 cm分别增加21.74%和33.33%。0~15、15~30 cm土壤POM和MAOM的碳、氮含量均高于30~45、45~60 cm土壤,且土壤总碳、全氮更多地分布于MAOM中。face处理极显著增加0~15 cm土层POM的碳、氮含量,其增幅分别为25.92%和24.45%;极显著提高0~15和15~30 cm土层MAOM的碳、氮含量,增幅分别为0~15 cm的32.62%(碳)和59.52%(氮)以及15~30 cm的42.34%(碳)和31.06%(氮)。face处理与对照各深度土壤有机碳红外特征峰形态基本一致,但主要吸收峰相对强度存在差异。与对照相比,face显著减小45~60 cm土壤芳香族官能团(1630 cm-1)的峰面积,增加0~15、15~30 cm土壤但降低30~45、45~60 cm土壤吸收峰峰面积的比值。综上,长期face处理有提高表层土壤总碳、全氮含量的趋势,其增量碳、氮更多地分布于MOAM中,同时提高表层土壤有机碳化学结构的稳定性,有利于表层土壤固碳。

关键词： face 土壤深度有机碳颗粒分组傅里叶红外光谱土壤固碳

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Surgical management of facial dog bite trauma:A contemporary perspective and review

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2023年第2期9卷 123-130页

作者： Tiffany Chen Maria Karim Zachary T.Grace Andrew R.Magdich Eric C.Carniol Brian E.Benson Peter F.Svider Hackensack Meridian School of Medicine NutleyNew JerseyUSA Carniol Plastic Surgery SummitNew JerseyUSA Hackensack Meridian Health Hackensack University Medical CenterHackensackNew JerseyUSA Bergen Medical Associates EmersonNew JerseyUsA

Objective:To perform a review evaluating management of and complications stemming from dog bite trauma sustained to the head and neck over the past decade.Data Sources:PubMed and Cochrane Library.Methods:The authors searched the PubMed and Cochrane Library databases for relevant published literature.A total of 12 peer-reviewed canine-exclusive series inclusive of 1384 patient cases describing facial dog bite trauma met inclusion criteria.Wounds including fractures,lacerations,contusions,and other soft-tissue injuries were evaluated.Demographics related to clinical course and management,operating room requirements,and antibiotic usage were compiled and analyzed.Initial trauma and surgical management complications were also assessed.Results:75.5%of patients sustaining dog bites required surgical intervention.Of these patients,7.8%suffered from postsurgical complications,including hypertrophic scarring(4.3%),postoperative infection(0.8%),or nerve deficits and persistent paresthesias(0.8%).Prophylactic antibiotics were administered to 44.3%of patients treated for facial dog bites and the overall infection rate was 5.6%.Concomitant fracture was present in 1.0%of patients.Conclusion:Primary closure,often in the OR may be necessary,with few cases requiring grafts or flaps.Surgeons should be aware that the most common complication is hypertrophic scarring.Further research is needed to elucidate the role of prophylactic antibiotics.

关键词： bite canine dog face facial injury laceration trauma

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Injective coloring of planar graphs with girth 5

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Frontiers of Mathematics in China 2022年第3期17卷 473-484页

作者： Yuehua BU Piaopiao YE School of Mathematical Sciences Zhejiang Normal UniversityJinhua 321004China Xingzhi College Zhejiang Normal UniversityJinhua 321004China

A coloring of a graph G is injective if its restriction to the neighbour of any vertex is injective.The injective chromatic number x_(i)(G)of a graph G is the least k such that there is an injective k-coloring.In this... 详细信息

关键词： Planar graph girth injective coloring face

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Partitioning Planar Graphs with Girth at Least 6 into Bounded Size Components

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Journal of Mathematical Research with Applications 2023年第1期43卷 16-24页

作者： Chunyu TIAN Lei SUN School of Mathematics and Statistics Shandong Normal University

An(Ok1、Ok2)-partition of a graph G is the partition of V(G) into two non-empty subsets V1and V2,such that G[V1] and G[V2] are graphs with components of order at most k1and k2,respectively.In this paper,we consider the problem of partitioning the vertex set of a planar graph with girth restriction such that each part induces a graph with components of bounded order.We prove that every planar graph with girth at least 6 and i-cycle is not intersecting with j-cycle admits an(O2,O3)-partition,where i∈{6,7,8} and j∈{6,7,8,9}.

关键词： planar graph face girth vertex partition discharging procedure

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face recognition using SIFT features under 3D meshes

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Journal of Central South University 2015年第5期22卷 1817-1825页

作者：张诚谷宇章胡珂立王营冠 Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences Department of Computer Science and Engineering Shaoxing University

Expression, occlusion, and pose variations are three main challenges for 3D face recognition. A novel method is presented to address 3D face recognition using scale-invariant feature transform(SIFT) features on 3D meshes. After preprocessing, shape index extrema on the 3D facial surface are selected as keypoints in the difference scale space and the unstable keypoints are removed after two screening steps. Then, a local coordinate system for each keypoint is established by principal component analysis(PCA).Next, two local geometric features are extracted around each keypoint through the local coordinate system. Additionally, the features are augmented by the symmetrization according to the approximate left-right symmetry in human face. The proposed method is evaluated on the Bosphorus, BU-3DFE, and Gavab databases, respectively. Good results are achieved on these three datasets. As a result, the proposed method proves robust to facial expression variations, partial external occlusions and large pose changes.

关键词： 3D face recognition scale-invariant feature transform(SIFT) expression occlusion large pose changes 3D meshes

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Spatial-temporal variation features and law of gas concentration in the fully mechanized working face under the condition of intermittent ventilation

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International Journal of Mining Science and Technology 2019年第6期29卷 963-969页

作者： Yinpin Cao Yimin Li Zhongning Zhou School of Electrical and Power Engineering China University of Mining & Technology

Based on the fluid mechanics and mass transfer theory,a mathematical model of the spatial-temporal variation of gas was derived to avoid the gas accident caused by the main fan stopping ventilation under the condition of intermittent ventilation in the tunnel.According to the actual parameters of the tunnel,a numerical calculation model was established.The spatial-temporal variation of gas concentration in the fully mechanized working face under the condition of intermittent ventilation was calculated by using the commercial package Fluent,and the correctness of the calculated results was verified by the actual monitoring data of the mine.Firstly,the gas concentration was calculated under different wind velocities at driving face in coal tunnel,and the result showed that the gas can be carried effectively by the wind when the wind velocity is about 1.8 m/s.Secondly,the distributions of wind velocity and gas concentration at driving face were studied at 1.8 m/s,and the result showed the gas concentration increased gradually with the distance close to the outlet,but the gas concentration almost kept constant at the height of driving face.Thirdly,the distribution of gas concentration was investigated with time after the ventilation was stopped and restarted,respectively.The gas concentration of test point gradually increased with the increment of downtime,when the downtime was 40 min,the gas concentration of test point 3 reached the maximum value.The gas concentration increased gradually and reached the maximum after10 min of restart,then sharply decreased and kept constant.

关键词： Fully mechanized working face Intermittent ventilation Gas concentration

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Mechanism of rock burst caused by fracture of key strata during irregular working face mining and its prevention methods

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International Journal of Mining Science and Technology 2019年第6期29卷 889-897页

作者： Zengqiang Yang Chang Liu Hengzhong Zhu Fuxing Xie Linming Dou Jianhang Chen School of Resource and Safety Engineering China University of Mining&TechnologyBeijing 100083China State Key Laboratory of Coal Resources and Mine Safety China University of Mining&TechnologyXuzhou 221116China Science&Technology Innovation Center Coal Mining and Designing DepartmentTiandi Science&Technology Co.LtdBeijing 100013China Mine Construction Branch of Research Institute China Coal Research InstituteBeijing 100013China

To study the occurrence mechanism of rock burst during mining the irregular working face,the study took irregular panel 7447 near fault tectonic as an engineering background.The spatial fracture characteristic of overlying strata was analyzed by Winkler elastic foundation beam theory.Furthermore,the influence law of panel width to suspended width and limit breaking span of key strata were also analyzed by thin plate theory.Through micro-seismic monitoring,theoretical analysis,numerical simulation and working resistance of support of field measurement,this study investigated the fracture characteristic of overlying strata and mechanism of rock burst in irregular working face.The results show that the fracture characteristic of overlying strata shows a spatial trapezoid structure,with the main roof being as an undersurface.The fracture form changes from vertical‘‘O-X"type to transverse‘‘O-X"type with the increase of trapezoidal height.From the narrow mining face to the wide mining face,the suspended width of key strata is greater than its limit breaking width,and a strong dynamic load is produced by the fracture of key strata.The numerical simulation and micro-seismic monitoring results show that the initial fracture position of key strata is close to tailgate 7447.Also there is a high static load caused by fault tectonic.The dynamic and static combined load induce rock burst.Accordingly,a cooperative control technology was proposed,which can weaken dynamic load by hard roof directional hydraulic fracture and enhance surrounding rock by supporting system.

关键词： Rock burst Irregular working face Key strata Dynamic and static combined load Cooperative control

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Dynamic failure risk of coal pillar formed by irregular shape longwall face:A case study

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International Journal of Mining Science and Technology 2018年第5期28卷 775-781页

作者： Yixin Zhao Hao Wang Shimin Liu Zonglong Mu Zhiguo Lu Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources School of Resources and Safety Engineering China University of Mining & Technology Department of Energy and Mineral Engineering G3 Center and EMS Energy Institute Pennsylvania State University University Park School of Mines China University of Mining & Technology

Irregular shape workface would result in the presence of coal pillar, which leads to high stress concentration and possibly induces coal bumps. In order to study the coal bump mechanism of pillars, static and dynamic stress overlapping(SDSO) method was proposed to explain the impacts of static stress concentration and tremors induced by mining activities. The stress and deformation in surrounding rock of mining face were analyzed based on the field case study at 1303 workface in Zhaolou Coal Mine in China.The results illustrate that the surrounding rock of a workface could be divided into four different zones,i.e., residual stress zone, stress decrease zone, stress increase zone and original stress zone. The stress increase zone is prone to failure under the SDSO impact loading conditions and will provide elastic energy for inducing coal bump. Based on the numerical modelling results, the evolution of static stress in coal pillar as the size of gob increasing was studied, and the impact of dynamic stress was investigated through analyzing the characteristics of tremor activities. The numerical results demonstrate the peak value of vertical stress in coal pillar rises from about 30 MPa with mining distance 10 m to 52.6 MPa with mining distance 120 m, and the location of peak stress transfers to the inner zone of coal pillars as the workface moves forward. For the daily tremor activities, tremors with high energy released indicate high dynamic stress disturbance on the surrounding rock, therefore, the impact of dynamic stressing is more serious during workface extension period because the tremor frequency and average energy after workface extension are higher than those before the workface extension.

关键词： Coal bump Coal pillar Tremor Irregular shape longwall face Static and dynamic stress overlapping

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