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Understanding the chemical coupling between ground-level ozone and oxides of nitrogen in ambient air at industrial and commercial sites in central India

arXiv

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arXiv 2023年

作者： Sadhukhan, Suchetana Aher, Satish Bhagwatrao Harshavardhanan, Pon Raj, Dharma Nandi, Subroto Shambhu Department of Physics School of Advanced Sciences and Languages VIT Bhopal University Madhya Pradesh Bhopal466114 India ICMR-National Institute for Research in Environmental Health Madhya Pradesh Bhopal462030 India School of Computing Science & Engineering VIT Bhopal University Madhya Pradesh Bhopal466114 India Division of Biostatistics and Bioinformatics ICMR-National Institute for Research in Environmental Health Madhya Pradesh Bhopal462030 India

This study investigates the hourly concentrations of Ground-level Ozone (O3), Nitric Oxide (NO), Nitrogen Dioxide (NO2), and Oxides of Nitrogen (NOx) in ambient air, along with the various meteorological parameters viz., ambient temperature, relative humidity, wind speed, and solar radiation over one year, from August 2020 to July 2021 for an industrial and commercial site in Madhya Pradesh, a central state in India. We also analyze the chemical coupling between the O3 and ambient NO, NO2, and NOx at both sites during the daytime. We focus on understanding how the concentration of the oxidant OX (a combination of ozone and nitrogen dioxide) changes in relation to levels of NOx (a combination of nitrogen oxides) to determine whether the atmospheric sources of OX are dependent on the NOx-independent or regional contributions and NOx-dependent or local contributions. We also observe a significant positive correlation of O3 with ambient temperature and solar radiation but a strong negative correlation with relative humidity for the considered period. We found the monthly variations of the pollutants' concentrations show a strong seasonality dependence. O3 concentration becomes highest/lowest during summer/monsoon for both sites. In contrast, NOx exhibits the maximum and minimum concentration during monsoon and summer for both sites. The daily variation shows the opposite trend for O3 and NOx. O3 reaches a peak at mid-day around 14: 00 Hrs when ambient temperature also goes to maximum and has the minimum value at night time due to lack of sunlight. Copyright © 2023, The Authors. All rights reserved.

关键词： Nitric oxide

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Training-free image style alignment for self-adapting domain shift on handheld ultrasound devices

arXiv

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arXiv 2024年

作者： Zeng, Hongye Zou, Ke Chen, Zhihao Gao, Yuchong Chen, Hongbo Zhang, Haibin Zhou, Kang Wang, Meng Goh, Rick Siow Mong Liu, Yong Jiang, Chang Zheng, Rui Fu, Huazhu School of Information Science and Technology ShanghaiTech University Shanghai China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai China University of Chinese Academy of Sciences Beijing China National Key Laboratory of Fundamental Science on Synthetic Vision College of Computer Science Sichuan University Chengdu China College of Intelligence and Computing Tianjin University Tianjin China Department of Computer Science and Engineering The Chinese University of Hong Kong Hong Kong Beth Israel Deaconess Medical Center Harvard Medical School Boston United States Institute of High Performance Computing Agency for Science Technology and Research Singapore Singapore Department of Orthopedics Zhongshan Hospital Fudan University Shanghai China Shanghai Engineering Research Center of Intelligent Vision and Imaging Shanghai China

Handheld ultrasound devices face usage limitations due to user inexperience and cannot benefit from supervised deep learning without extensive expert annotations. Moreover, the models trained on standard ultrasound device data are constrained by training data distribution and perform poorly when directly applied to handheld device data. In this study, we propose the Training-free Image Style Alignment (TISA) framework to align the style of handheld device data to those of standard devices. The proposed TISA can directly infer handheld device images without extra training and is suited for clinical applications. We show that TISA performs better and more stably in medical detection and segmentation tasks for handheld device data. We further validate TISA as the clinical model for automatic measurements of spinal curvature and carotid intima-media thickness. The automatic measurements agree well with manual measurements made by human experts and the measurement errors remain within clinically acceptable ranges. We demonstrate the potential for TISA to facilitate automatic diagnosis on handheld ultrasound devices and expedite their eventual widespread use. © 2024, CC BY-NC-SA.

关键词： Deep learning

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One-Iteration-per-Update 94LVI Algorithm Solving Time-Varying Quadratic Programming in Real Time with Numerical and Graphical Results

One-Iteration-per-Update 94LVI Algorithm Solving Time-Varyin...

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第34届中国控制与决策会议

作者： Yunong Zhang Zhiwen Yuan Tangke Xu School of Computer Science and Engineering Sun Yat-sen University Guangdong Key Laboratory of Modern Control Technology Key Laboratory of Machine Intelligence and Advanced Computing Ministry of Education Research Institute of Sun Yat-sen University in Shenzhen

Recently,there have been many methods to solve quadratic programming(QP) *** this work,on the basis of linear variational inequality(LVI),a simple and effective algorithmic method(i.e.,one-iteration-per-update 94 LVI algorithm)is proposed for solving the time-varying QP problem,which is subject to time-varying linear equality,inequality and bound constraints at the same *** that the normal 94 LVI algorithm is usually used to find the optimal solution of the static QP problem in the ***,we transform the QP problem into a piecewise-linear projection equation(PLPE).Then,the continuous time-varying QP problem is divided into many static QP problems via sampling time interval ***,we use the normal 94 LVI algorithm to update with only one iteration based on the solution of previous sampling time instant,and finally we get the solution of each sampling time *** numerical experiments,as a novel approach,the one-iterationper-update 94 LVI is able to get the solution of each sampling time instant much quickly and quite accurately when solving the time-varying QP problem.

关键词： time-varying QP problem linear variational inequality piecewise-linear projection equation one-iteration-perupdate 94LVI numerical algorithm

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Low-cycle fatigue life prediction of a polycrystalline nickel-base superalloy using crystal plasticity modelling approach

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Journal of Materials Science & Technology 2020年第3期38卷 28-38页

作者： Guang-Jian Yuan Xian-Cheng Zhang Bo Chen Shan-Tung Tu Cheng-Cheng Zhang Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China The Institute for Advanced Manufacturing and Engineering Faculty of EngineeringEnvironment and ComputingCoventry UniversityCoventry CV65LZUK AECC Commercial Aircraft Engine Co.LTD Shanghai Engineering Research Center for Commercial Aircraft EngineShanghai 201108China

A crystal plasticity model is developed to predict the cyclic plasticity during the low-cycle fatigue of GH4169 *** plastic slip and energy dissipation as fatigue indicator parameters(FIPs)are used to predict fatigue crack initiation and the fatigue life until *** show that fatigue damage is most likely to initiate at triple points and grain boundaries where severe plastic slip and energy dissipation are *** predicted fatigue life until failure is within the scatter band of factor 2 when compared with experimental data for the total strain amplitudes ranging from 0.8%to 2.4%.Microscopically,the adjacent grain arrangements and their interactions account for the stress *** addition,different sets of grain orientations with the same total grain numbers of 150 were generated using the present *** show that different sets have significant influence on the distribution of stresses between each individual grain at the meso-scale,although little effect is found on the macroscopic length-scale.

关键词： Crystal plasticity Fatigue Finite element Life prediction Micro-mechanics Nickel-base superalloy

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Long-Tailed Multi-Label Classification with Noisy Label of Thoracic Diseases from Chest X-Ray

Long-Tailed Multi-Label Classification with Noisy Label of T...

引用

IEEE International Symposium on Biomedical Imaging

作者： Haoran Lai Qingsong Yao Zhiyang He Xiaodong Tao S. Kevin Zhou School of Biomedical Engineering Division of Life Sciences and Medicine University of Science and Technology of China Hefei P.R. China Suzhou Institute for Advanced Research University of Science and Technology of China Suzhou P.R. China Key Lab of Intelligent Information Processing of Chinese Academy of Sciences (CAS) Institute of Computing Technology CAS Beijing China Medical Business Department iFlytek Co. Ltd Hefei China

ISBN: (数字)9798350313338

ISBN: (纸本)9798350313345

Chest X-rays (CXR) often reveal rare diseases, demanding precise diagnosis. However, current computer-aided diagnosis (CAD) methods focus on common diseases, leading to inadequate detection of rare conditions due to the absence of comprehensive datasets. To overcome this, we present a novel benchmark for long-tailed multi-label classification in CXRs, encapsulating both common and rare thoracic diseases. Our approach includes developing the "LTML-MIMIC-CXR" dataset, an augmentation of MIMIC-CXR with 26 additional rare diseases. We propose a baseline method for this classification challenge, integrating adaptive negative regularization to address negative logits' over-suppression in tail classes, and a large loss reconsideration strategy for correcting noisy labels from automated annotations. Our evaluation on LTML- MIMIC-CXR demonstrates significant advancements in rare disease detection. This work establishes a foundation for robust CAD methods, achieving a balance in identifying a spectrum of thoracic diseases in CXRs. Access to our code and dataset is provided at: https://***/laihaoran/LTML-MIMIC-CXR.

关键词： Design automation Annotations MIMICs Pipelines Tail Computer aided diagnosis Noise measurement

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Experimental and kinetic modeling study of oxidation of acetonitrile 38th

Experimental and kinetic modeling study of oxidation of acet...

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38th International Symposium on Combustion, 2021

作者： Alzueta, María U. Guerrero, Marta Millera, Ángela Marshall, Paul Glarborg, Peter Aragón Institute of Engineering Research I3A Department of Chemical and Environmental Engineering University of Zaragoza Zaragoza 50018 Spain Department of Chemistry Center for Advanced Scientific Computing and Modeling University of North Texas 1155 Union Circle 305070 Denton TX 76203-5017 United States Dtu Chemical Engineering Technical University of Denmark Lyngby DK-2800 Denmark

Oxidation of acetonitrile was studied in a flow reactor in the absence and presence of nitric oxide. The experiments were conducted at atmospheric pressure in the temperature range 1150 K–1450 K, varying the excess air ratio from slightly fuel-lean to very lean. Oxidation of acetonitrile was slow below 1300 K. NO, hydrogen cyanide, and nitrous oxide were detected as important products. A detailed chemical kinetic model for oxidation of acetonitrile was developed, based on a critical evaluation of data from literature. The rate coefficients for the reactions of acetonitrile and CH₂CN with O₂ were calculated from ab initio theory. Modeling predictions were in satisfactory agreement with experiments. Calculations were sensitive to thermal dissociation of acrolein and to the branching fraction for CH₃CN + OH to CH₂CN + H₂O and HOCN +CH₃ , respectively.

关键词： Kinetic theory

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Network analysis reveals news press landscape and asymmetric user polarization

arXiv

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arXiv 2024年

作者： Lee, Byunghwee Ryu, Hyo-Sun Lee, Jae Kook Jeong, Hawoong Kim, Beom Jun Center for Complex Networks and Systems Research Luddy School of Informatics Computing and Engineering Indiana University BloomingtonIN47408 United States Institute of Basic Science Sungkyunkwan University Suwon16419 Korea Republic of Department of Media and Communication Sungkyunkwan University Seoul03063 Korea Republic of Department of Physics Korea Advanced Institute of Science and Technology Daejeon34141 Korea Republic of Department of Physics Sungkyunkwan University Suwon16419 Korea Republic of

Unlike traditional media, online news platforms allow users to consume content that suits their tastes and to facilitate interactions with other people. However, as more personalized consumption of information and interaction with like-minded users increase, ideological bias can inadvertently increase and contribute to the formation of echo chambers, reinforcing the polarization of opinions. Although the structural characteristics of polarization among different ideological groups in online spaces have been extensively studied, research into how these groups emotionally interact with each other has not been as thoroughly explored. From this perspective, we investigate both structural and affective polarization between news media user groups on Naver News, South Korea's largest online news portal, during the period of 2022 Korean presidential election. By utilizing the dataset comprising 333,014 articles and over 36 million user comments, we uncover two distinct groups of users characterized by opposing political leanings and re- veal significant bias and polarization among them. Additionally, we reveal the existence of echo chambers within co-commenting networks and investigate the asymmetric affective interaction patterns between the two polarized groups. Classification task of news media articles based on the distinct comment response patterns support the notion that different political groups may employ distinct communication strategies. Our approach based on network analysis on large-scale comment dataset offers novel insights into characteristics of user polarization in the online news platforms and the nuanced interaction nature between user groups. © 2024, CC BY.

关键词：

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Lung Nodule Segmentation and Uncertain Region Prediction with an Uncertainty-Aware Attention Mechanism

arXiv

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arXiv 2023年

作者： Yang, Han Wang, Qiuli Zhang, Yue An, Zhulin Chen, Liu Zhang, Xiaohong Zhou, S. Kevin School of Biomedical Engineering Division of Life Sciences and Medicine University of Science and Technology of China Anhui Hefei230026 China Suzhou Institute for Advanced Research University of Science and Technology of China Jiangsu Suzhou215123 China The Institute of Computing Technology Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China Department of Radiology The First Affiliated Hospital of Army Medical University Chongqing400032 China School of Big Data & Software Engineering Chongqing University Chongqing401331 China Institute of Computing Technology Beijing100190 China

Radiologists possess diverse training and clinical experiences, leading to variations in the segmentation annotations of lung nodules and resulting in segmentation uncertainty. Conventional methods typically select a single annotation as the learning target or attempt to learn a latent space comprising multiple annotations. However, these approaches fail to leverage the valuable information inherent in the consensus and disagreements among the multiple annotations. In this paper, we propose an Uncertainty-Aware Attention Mechanism (UAAM) that utilizes consensus and disagreements among multiple annotations to facilitate better segmentation. To this end, we introduce the Multi-Confidence Mask (MCM), which combines a Low-Confidence (LC) Mask and a High-Confidence (HC) Mask. The LC mask indicates regions with low segmentation confidence, where radiologists may have different segmentation choices. Following UAAM, we further design an Uncertainty-Guide Multi-Confidence Segmentation Network (UGMCS-Net), which contains three modules: a Feature Extracting Module that captures a general feature of a lung nodule, an Uncertainty-Aware Module that produces three features for the annotations’ union, intersection, and annotation set, and an Intersection-Union Constraining Module that uses distances between the three features to balance the predictions of final segmentation and MCM. To comprehensively demonstrate the performance of our method, we propose a Complex Nodule Validation on LIDC-IDRI, which tests UGMCS-Net’s segmentation performance on lung nodules that are difficult to segment using common methods. Experimental results demonstrate that our method can significantly improve the segmentation performance on nodules that are difficult to segment using conventional methods. © 2023, CC BY-NC-ND.

关键词： Computerized tomography

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Network Analysis Reveals News Press Landscape and Asymmetric User Polarization

SSRN

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SSRN 2024年

Unlike traditional media, online news platforms allow users to consume content that suits their tastes and to facilitate interactions with other people. However, as more personalized consumption of information and interaction with like-minded users increase, ideological bias can inadvertently increase and contribute to the formation of echo chambers, reinforcing the polarization of opinions. Although the structural characteristics of polarization among different ideological groups in online spaces have been extensively studied, research into how these groups emotionally interact with each other has not been as thoroughly explored. From this perspective, we investigate both structural and affective polarization between news media user groups on Naver News, South Korea's largest online news portal, during the period of 2022 Korean presidential election. By utilizing the dataset comprising 333,014 articles and over 36 million user comments, we uncover two distinct groups of users characterized by opposing political leanings and reveal significant bias and polarization among them. Additionally, we reveal the existence of echo chambers within co-commenting networks and investigate the asymmetric affective interaction patterns between the two polarized groups. Classification task of news media articles based on the distinct comment response patterns support the notion that different political groups may employ distinct communication strategies. Our approach based on network analysis on large-scale comment dataset offers novel insights into characteristics of user polarization in the online news platforms and the nuanced interaction nature between user groups. © 2024, The Authors. All rights reserved.

关键词： Polarization

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Cooperative Hierarchical Coverage Control of Multi-Agent Systems with Non-holonomic Constraints in Poriferous Environments

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IEEE Transactions on Control of Network Systems 2025年

作者： Zou, Jiayu Zhang, Hai-Tao Zhai, Chao Xing, Ning Ma, Yong Liu, Xingjian Huazhong University of Science and Technology School of Artificial Intelligence and Automation The MOE Engineering Research Center of Autonomous Intelligent Unmanned Systems The State Key Laboratory of Digital Manufacturing Equipment and Technology Wuhan430074 China China University of Geosciences School of Automation China The MOE Engineering Research Center of Intelligent Technology for Geo-Exploration Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan430074 China Academician Workstation of China COSCO Shipping Corporation Ltd. Shanghai200120 China Wuhan University of Technology Sanya Science and Education Innovation Park Sanya572000 China Wuhan University of Technology Chongqing Research Institute Chongqing401120 China

It has long posed a challenging task to optimally deploy multi-agent systems (MASs) to cooperatively coverage poriferous environments in real cooperative detection applications. In response to this challenge, this paper proposes a hierarchical coverage control (HCC) protocol for MASs to perform sector-based coverage operations. First, a distributed Voronoi partition-based sweep-and-assign protocol, combined with a sectorial partition method, is developed, enabling the segmentation of a whole poriferous region into multiple sectorial sub-subregions. Following this procedure, an extreme search scheme is developed to determine the optimal amount of agents for each subregion. After this allocation, a distributed controller is proposed to deploy the agents, considering non-holonomic constraints, into designated niche positions. Additionally, sufficient conditions are derived to guarantee the asymptotical stability of the present HCC. The analytical challenge of the present study stems from the non-convex characteristics inherent in the loss function induced by porous environments. This non-convexity renders the task of globally optimizing the assignment of MASs intractable. Finally, numerical simulations are conducted to validate the effectiveness of the present coverage control approach. © 2014 IEEE.

关键词： Nonlinear control systems

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