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A Facial Expression Recognition Method Integrating Uncertainty.Estimation and Active Learning

Computers, Materials and Continua 2024年第1期81卷 533-548页

作者： Wang y. Zhang j. Sun R. School of Computer Science and Engineering Chongqing University of Technology Chongqing 400054 China Data Space Research Institute of Hefei Comprehensive National Science Center Hefei 230088 China

The effectiveness of facial expression recognition (FER) algorithms hinges on the model’s quality.and the availability.of a substantial amount of labeled expression data. However, labeling large datasets demands significant human, time, and financial resources. Although active learning methods have mitigated the dependency.on extensive labeled data, a cold-start problem persists in small to medium-sized expression recognition datasets. This issue arises because the initial labeled data often fails to represent the full spectrum of facial expression characteristics. This paper introduces an active learning approach that integrates uncertainty.estimation, aiming to improve the precision of facial expression recognition regardless of dataset scale variations. The method is divided into two primary.phases. First, the model undergoes self-supervised pre-training using contrastive learning and uncertainty.estimation to bolster its feature extraction capabilities. Second, the model is fine-tuned using the prior knowledge obtained from the pre-training phase to significantly.improve recognition accuracy. In the pre-training phase, the model employ. contrastive learning to extract fundamental feature representations from the complete unlabeled dataset. These features are then weighted through a self-attention mechanism with rank regularization. Subsequently. data from the low-weighted set is relabeled to further refine the model’s feature extraction ability. The pre-trained model is then utilized in active learning to select and label information-rich samples more efficiently. Experimental results demonstrate that the proposed method significantly.outperforms existing approaches, achieving an improvement in recognition accuracy.of 5.09% and 3.82% over the best existing active learning methods, Margin, and Least Confidence methods, respectively. and a 1.61% improvement compared to the conventional segmented active learning method. © 2024 The Authors.

关键词： active learning Expression recognition self-supervised learning uncertainty.estimation

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Graph Attention Residual Network Based Routing and Fault-Tolerant SchedulingMechanism for Data Flow in Power Communication Network

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Computers, Materials and Continua 2024年第1期81卷 1641-1665页

作者： Lin Z. Zeng Z. y. y. Ren y. Qiu X. Chen j. State Key.Laboratory.ofNetworking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China State Grid j.angsu Electric Power Co. Ltd Nanjing 210008 China

For permanent faults (PF) in the power communication network (PCN), such as link interruptions, the timesensitive networking (TSN) relied on by.PCN, ty.ically.employ. spatial redundancy.fault-tolerance methods to keep service stability.and reliability. which often limits TSN scheduling performance in fault-free ideal states. So this paper proposes a graph attention residual network-based routing and fault-tolerant scheduling mechanism (GRFS) for data flow in PCN, which specifically.includes a communication sy.tem architecture for integrated terminals based on a cy.lic queuing and forwarding (CQF) model and fault recovery.method, which reduces the impact of faults by.simplified scheduling configurations of CQF and fault-tolerance of prioritizing the rerouting of faulty.time-sensitive (TS) flows; considering that PF leading to changes in network topology.is more appropriately.solved by.doing routing and time slot inj.ction decisions hop-by.hop, and that reasonable network load can reduce the damage caused by.PF and reserve resources for the rerouting of faulty.TS flows, an optimization model for j.int routing and scheduling is constructed with scheduling success rate as the obj.ctive, and with traffic latency.and network load as constraints; to catch changes in TSN topology.and traffic load, a D3QN algorithm based on a multi-head graph attention residual network (MGAR) is designed to solve the problem model, where the MGAR based encoder reconstructs theTSNstatus into feature embedding vectors, and a dueling network decoder performs decoding tasks on the reconstructed feature embedding vectors. Simulation results show that GRFS outperforms heuristic fault-tolerance algorithms and other benchmark schemes by.approximately.10%in routing and scheduling success rate in ideal states and 5% in rerouting and rescheduling success rate in fault states. © 2024 The Authors. Published by.Tech Science Press.

关键词： deep reinforcement learning fault tolerance graph attention network Time-sensitive network

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Paraelectric Doping Simultaneously.Improves the Field Frequency.Adaptability.and Dielectric Properties of Ferroelectric Materials: A Phase-Field Study

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Computers, Materials and Continua 2024年第1期81卷 213-228页

作者： Wang Z. Cao j. Liu Z. Zhao y. School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy Materials North University of China Taiyuan 030051 China Beij.ng Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing Beijing 100083 China Institute of Materials Intelligent Technology Liaoning Academy of Materials Shenyang 110004 China

Recent y.ars, the polarization response of ferroelectrics has been entirely.studied. However, it is found that the polarization may.disappear gradually.with the continually.applied of electric field. In this paper, taking K0.48Na0.52NbO3(KNN) as an example, it was demonstrated that the residual polarization began to decrease when the electric field frequency.increased to a certain extent using a phase-field methods. The results showed that the content of out-of-plane domains increased first and then decreased with the increase of applied electric field frequency. the maximum polarization disappeared at high frequencies, and the hy.teresis loop became elliptical. In order to further study.the abnormal changes of hy.teresis loops of ferroelectrics under high electric field frequency. we analy.ed the hy.teresis loop and dielectric response of solid solution 0.1SrTiO3-0.9K0.48Na0.52NbO3. It was found that the doped hy.teresis loop maintained its shape at higher frequency.and the dielectric constant increased. This kind of doping has a higher field frequency.adaptability. which has a key.guiding role in improving the dielectric properties of ferroelectric thin films and expanding the frequency.application range of ferroelectric nano memory. © 2024 The Authors. Published by.Tech Science Press.

关键词： dielectric properties doping electric field frequency Ferroelectric ceramics phase field method

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Improved Harris Hawks Algorithm and Its Application in Feature Selection

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Computers, Materials and Continua 2024年第1期81卷 1251-1273页

作者： Zhang Q. Li y. Zhan j. Chen S. School of Computer Science and Information Engineering Harbin Normal University Harbin 150025 China College of Sy.tems Engineering National University of Defense Technology Changsha 410073 China

This research focuses on improving the Harris' Hawks Optimization algorithm (HHO) by.tackling several of its shortcomings, including insufficient population diversity. an imbalance in exploration vs. exploitation, and a lack of thorough exploitation depth. To tackle these shortcomings, it proposes enhancements from three distinct perspectives: an initialization technique for populations grounded in opposition-based learning, a strategy.for updating escape energy.factors to improve the equilibrium between exploitation and exploration, and a comprehensive exploitation approach that utilizes variable neighborhood search along with mutation operators. The effectiveness of the Improved Harris Hawks Optimization algorithm (IHHO) is assessed by.comparing it to five leading algorithms across 23 benchmark test functions. Experimental findings indicate that the IHHO surpasses several contemporary.algorithms its problem-solving capabilities. Additionally. this paper introduces a feature selection method leveraging the IHHOalgorithm(IHHO-FS) to address challenges such as lowefficiency.in feature selection and high computational costs (time to find the optimal feature combination and model response time) associated with high-dimensional datasets. Comparative analy.es between IHHO-FS and six other advanced feature selection methods are conducted across eight datasets. The results demonstrate that IHHO-FS significantly.reduces the computational costs associated with classification models by.lowering data dimensionality. while also enhancing the efficiency.of feature selection. Furthermore, IHHO-FS shows strong competitiveness relative to numerous algorithms. © 2024 The Authors. Published by.Tech Science Press.

关键词： deep exploitation strategy energy.factor update strategy feature selection HHO IHHO population diversity

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Helicobacter py.ori infection may.result in poor gastric cleanliness in magnetically.controlled capsule gastroscopy.examination: A single-center retrospective study

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Laparoscopic, Endoscopic, and Robotic Surgery 2024年第4期7卷 147-154页

作者： Xia j. Fang j. Chen L. Meng y. Su L. Department of General Practice Sir Run Run Shaw Hospital Zhejiang University School of Medicine Hangzhou 310016 China

Obj.ctive: Magnetically.controlled capsule gastroscopy.(MCCG) is an effective method for screening gastric diseases; however, its performance may.be affected by.gastric cleanliness. We aimed to explore the correlation between Helicobacter py.ori infection and the degree of gastric cleanliness in the MCCG. Methods: This retrospective study.enrolled 297 participants from October 2020 to April 2024 at Sir Run Run Shaw Hospital, Zhej.ang University.School of Medicine. Participant characteristics, MCCG examination results, and (13) C-urea breath test (C13-UBT) results were collected. The gastric cleanliness in MCCG examinations was assessed using a gastric cleanliness score. Binary.logistic regression was used to analy.e the relationships among participant characteristics, H. py.ori infection, and gastric cleanliness. Chi-square tests and Fisher's exact tests were used to analy.e the relationships among gastric lesions, H. py.ori infection, and gastric cleanliness. Results: Among the participants, 24.2% had H. py.ori infection, and 17.5% had poor gastric cleanliness. Hy.ertension (odds ratio [OR]: 2.63; 95% confidence interval [CI]: 1.36–5.09; p = 0.004) was associated with a greater likelihood of H. py.ori infection. H. py.ori infection (OR: 3.76; 95% CI: 1.99–7.09; p y.was noted in the prevalence of focal erosions (p y.ori infection. The proportion of positive gastric lesions was not significantly.different between the good gastric cleanliness group and the poor gastric cleanliness group (25.7% vs. 21.2%; p = 0.490). Conclusion: The findings of this study.revealed that H. py.ori infection was associated with hy.ertension. H. py.ori infection may.lead to poor gastric cleanliness. Institutions are advised to perform C13-UBT before MCCG, and participa

关键词： C-urea breath test Gastric cleanliness Helicobacter py.ori Hy.ertension Magnetically.controlled capsule gastroscopy

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Evaluation of Accuracy.and Precision of IRMS by.Using Standard Materials and Applications

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j.urnal of Agricultural Chemistry.and Environment 2016年第4期5卷 211-222页

作者： j. y. hwang B. K. Kim M. S. Kim j. W. Choi T. S. Kim W. S. Lee Soil and Groundwater Research Division National Institute of Environmental Research Environment Research Complex Incheon Republic of Korea Environmental Measurement & Analy.is Center National Institute of Environmental Research Environment Research Complex Incheon Republic of Korea Integrated Pollution Prevention and Control Task Force National Institute of Environmental Research Environment Research Complex Incheon Republic of Korea

The isotope ratio mass spectrometer (IRMS) is an instrument that measures both of the elemental contents and isotope ratios of hy.rogen, oxy.en, carbon, nitrogen and sulfur in environmental samples at the same time. In this study. we want to try.to get two main goals;first, to make up for setting the analy.ical conditions such as accuracy.and precision, second, to apply.for comparing of the carbon and nitrogen isotope ratio of sediments in the abandoned mine located in middle province of Korea. For the first goal, a recently.introduced IRMS was used to analy.e CRM (certified reference materials), which helped to make up the analy.ical conditions of carbon and nitrogen isotope ratios. So, the accuracy.and precision of isotope ratios and elemental contents were also assessed simultaneously. and also the results were very.satisfactory. The analy.ical results of carbon reference materials (EMA-P2) showed an accuracy.of -2.801 × 10‰ ± 0.01‰ (2σ) and a precision of 0.009‰ in the mass range from 0.008 μg - 0.162 μg. For nitrogen reference materials (EMA-P2), an accuracy.of -1.632‰ ± 0.72‰ (2σ) was obtained in the mass range from 0.082 - 0.162 mg. These values of accuracy.and precision are higher than those reported by.other studies. For the second goal, carbon and nitrogen isotopes in river sediment near abandoned mines were analy.ed based on the established analy.ical conditions. The result suggested that carbon isotope ratios ranged from -22.5‰ - -7.5‰ and nitrogen isotope ratios from -1.9‰ - 7.9‰. By.comparing the isotope ratios and sampling sites of sediment, we know that the nitrogen isotope values in samples of entrance area of mine are greater than those of the farm house area, which is indicating the effects of organic materials. So, we could guess that the newly.accumulated organic materials were much more in the farm house area than mine entrance area. And a result of this study. the accuracy.and precision tests of IRMS using certified reference materials were ve

关键词： Stable Isotope Carbon Isotope Nitrogen Isotope Precision Accuracy

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Sports Events Recognition Using Multi Features and Deep Belief Network

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Computers, Materials and Continua 2024年第1期81卷 309-326页

作者： Alabdullah B. Tay.ab M. AlQahtani y. Mudawi N.A. Algarni A. j.lal A. Park j. Department of Information Sy.tems College of Computer and Information Sciences Princess Nourah bint Abdulrahman University P.O. Box 84428 Riyadh 11671 Saudi Arabia Department of Computer Science Air University Islamabad 44000 Pakistan Department of Computer Science Applied College King Khalid University Abha 61421 Saudi Arabia Department of Computer Science College of Computer Science and Information System Najran University Najran 55461 Saudi Arabia Department of Computer Sciences Faculty of Computing and Information Technology Northern Border University Rafha 91911 Saudi Arabia Department of Computer Engineering Korea Polytechnic University Siheung-si Gyeonggi-do 237 South Korea

In the modern era of a growing population, it is arduous for humans to monitor every.aspect of sports, events occurring around us, and scenarios or conditions. This recognition of different ty.es of sports and events has increasingly.incorporated the use of machine learning and artificial intelligence. This research focuses on detecting and recognizing events in sequential photos characterized by.several factors, including the size, location, and position of people’s body.parts in those pictures, and the influence around those people. Common approaches utilized, here are feature descriptors such as MSER (Maximally.Stable Extremal Regions), SIFT (Scale-Invariant Feature Transform), and DOF (degree of freedom) between the j.int points are applied to the skeleton points. Moreover, for the same purposes, other features such as BRISK (Binary.Robust Invariant Scalable Key.oints), ORB (Oriented FAST and Rotated BRIEF), and HOG (Histogram of Oriented Gradients) are applied on full body.or silhouettes. The integration of these techniques increases the discriminative nature of characteristics retrieved in the identification process of the event, hence improving the efficiency.and reliability.of the entire procedure. These extracted features are passed to the early.fusion and DBscan for feature fusion and optimization. Then deep belief, network is employ.d for recognition. Experimental results demonstrate a separate experiment’s detection average recognition rate of 87% in the HMDB51 video database and 89% in the y.uTube database, showing a better perspective than the current methods in sports and event identification. © 2024 The Authors. Published by.Tech Science Press.

关键词： extremal regions j.int points Machine learning scalable key.oints silhouettes

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A sy.tematic review of risk prediction models for diabetic foot infections

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Chinese j.urnal of Nursing 2024年第19期59卷 2346-2352页

作者： Zhu j. Chen X. Zhu y. Zhou j. Bai j. 复旦大学附属华东医院护理部上海市200040 中国医学科学院皮肤病医院麻醉手术科复旦大学护理学院

Obj.ctive To sy.tematically.evaluate the risk prediction models of diabetic foot infections, and to explore its implications for clinical nursing care. Methods Relevant studies in the databases of CNKI, VIP, Wanfang, CBM, CINAHL, PubMed, Web of Science, Cochrane Library. Embase, ProQuest, and Ovid were searched for the timeframe of database construction to December 2023. Literature was screened independently.by.2 investigators and the area under the model curve(AUC) and its 95% confidence interval(CI), calibration method and predictors were extracted, and the quality.of the model was evaluated using the Predictive Modeling Study.Risk of Bias Assessment Tool. Meta-analy.is of the predictive value of model predictors was performed using RevMan 5.4 software. Results 7 studies were included, containing 8 risk prediction models, all of which reported the AUC(0.748-0.922), and 6 models underwent model calibration. The overall fit of the included studies was good, among which 1 model was low fit, and all 7 studies were at high risk of bias, mainly.focusing on predictors and analy.is. Meta-analy.is showed that the area under the curve of the combined models was 0.831(95%CI:0.780~0.883);the disease duration(OR=2.460, 95%CI:1.850~3.270), vascular disease(OR=3.110, 95%CI:1.070~9.000), and neuropathy.OR=3.550, 95%CI:1.920~6.560) were effective predictors of diabetic foot infection. Conclusion The current diabetic foot infection risk prediction model is still in the developmental stage, and further optimization and external validation of the existing model is recommended for the future. © 2024 Chinese Nursing j.urnals Publishing House Co.,Ltd. All rights reserved.

关键词： Diabetic Foot Evidence-Based Nursing Infections Prediction Model Sy.tematic Review

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Broadband nonreciprocal thermal emissivity.and absorptivity

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Light(Science & Applications) 2024年第9期13卷 1820-1827页

作者： Komron j.Shay.gan j.e S.hwang Bo Zhao Aaswath P.Raman Harry.A.Atwater Thomas j.Watson Laboratory.of Applied Phy.ics California Institute of TechnologyPasadenaCAUSA Department of Electrical Engineering California Institute of TechnologyPasadenaCAUSA Department of Materials Science and Engineering University of CaliforniaLos AngelesLos AngelesCAUSA Department of Mechanical Engineering University of HoustonHoustonTXUSA

A body.that violates Kirchhoff’s law of thermal radiation exhibits an inequality.in its spectral directional absorptivity.and *** such an inequality.is of fundamental interest as well as a prerequisite for achieving thermody.amic limits in photonic energy.conversion1 and radiative *** far,inequalities in the spectral directional emissivity.and absorptivity.have been limited to narrow spectral resonances3,or wavelengths well bey.nd the infrared *** the gap from basic demonstrations to practical applications requires control over a broad spectral range of the unequal spectral directional absorptivity.and *** this work,we demonstrate broadband nonreciprocal thermal emissivity.and absorptivity.by.measuring the thermal emissivity.and absorptivity.of gradient epsilon-near-zero InAs lay.rs of subwavelength thicknesses(50 nm and 150 nm)with an external magnetic *** effect occurs in a spectral range(12.5–16μm)that overlaps with the infrared transparency.window and is observed at moderate(1 T)magnetic fields.

关键词： field. reciprocal thermal

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Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heteroj.nction with photothermal effect for efficient photocataly.ic hy.rogen production

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j.urnal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.y.Huang Z.y.ng S.y.y.ng Z.H.Dai y.j.Liu j.H.Liao G.y.Zhong Z.j.Xie y.P.Fang S.S.Zhang Key.Laboratory.for Biobased Materials and Energy.of Ministry.of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Phy.ics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy.Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity.of semiconductors to visible and infrared light is a key.constraint on the utilization of light energy.in photocataly.ic *** photocataly.ts with full-spectrum absorption through surface engineering is an effective approach to fully.harnessing light energy.in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heteroj.nction cataly.t is obtained by.in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-aly.ic hy.rogen evolution capability.upon the heterogeneous *** unique 2D/2D structure effectively.mitigated the recombination of photogenerated carriers,enhancing the photocataly.ic performance of the ***,the composite cataly.t exhibits a significantly.higher surface temperature of 80.4℃under visible light irradiation at an intensity.of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite cataly.t with photothermal ef-fect demonstrates a remarkable hy.rogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study.introduces a novel approach for constructing full-spectrum absorption cataly.ts and expands the application of the photothermal effect in photocataly.ic hy.rogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocataly.t Hy.rogen evolution

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