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A Trust Evaluation Mechanism Based on Autoencoder Clustering Algorithm for Edge Device Access of IoT

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Computers, Materials & Continua 2024年第2期78卷 1881-1895页

作者： xiao Feng zheng y.an Cyber Security Academy Beijing University of Posts and TelecommunicationsBeijing100876China Department of Cyberspace Security Beijing Electronic Science and Technology InstituteBeijing100070China State Grid Info-Telecom Great Power Science and Technology Co. Ltd.Beijing102211China

First,we propose a cross-domain authentication architecture based on trust evaluation mechanism,including registration,certificate issuance,and cross-domain authentication processes.A direct trust evaluation mechanism based on the time decay factor is proposed,taking into account the influence of historical interaction *** weight the time attenuation factor to each historical interaction record for updating and got the new historical record *** refer to the beta distribution to enhance the flexibility.and adaptability of the direct trust assessment model to better capture time trends in the historical *** we propose an autoencoder-based trust clustering *** perform feature extraction based on *** leibler(KL)divergence is used to calculate the reconstruction *** constructing a convolutional autoencoder,we introduce convolutional neural networks to improve training efficiency.and introduce sparse constraints into the hidden layer of the *** sparse penalty term in the loss function measures the difference through the KL *** clustering is performed based on the density based spatial clustering of applications with noise(DBSCAN)clustering *** the clustering process,edge nodes have a variety of trustworthy attribute *** assign different attribute weights according to the relative importance of each attribute in the clustering process,and a larger weight means that the attribute occupies a greater weight in the calculation of ***,we introduced adaptive weights to calculate comprehensive trust *** experiments prove that our trust evaluation mechanism has excellent reliability.and accuracy.

关键词： Cross-domain authentication trust evaluation autoencoder

Multi-timescale optimization scheduling of interconnected data centers based on model predictive control

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Frontiers in Energy 2024年第1期18卷 28-41页

作者： xiao GUO yanbo CHE Zhihao zheng Jiulong SUN Energy Power Electrical Automation and Information EngineeringTianjin UniversityTianjin 300072China

With the promotion of“dual carbon”strategy,data center(DC)access to high-penetration renewable energy sources(RESs)has become a trend in the ***,the uncertainty of RES poses challenges to the safe and stable operation of DCs and power *** this paper,a multi-timescale optimal scheduling model is established for interconnected data centers(IDCs)based on model predictive control(MPC),including day-ahead optimization,intraday rolling optimization,and intraday real-time *** day-ahead optimization stage aims at the lowest operating cost,the rolling optimization stage aims at the lowest intraday economic cost,and the real-time correction aims at the lowest power fluctuation,eliminating the impact of prediction errors through coordinated multi-timescale *** simulation results show that the economic loss is reduced by 19.6%,and the power fluctuation is decreased by 15.23%.

关键词： model predictive control interconnected data center multi-timescale optimized scheduling distributed power supply/landscape uncertainty

Joint Sample Position Based Noise Filtering and Mean Shift Clustering for Imbalanced Classification Learning

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Tsinghua Science and Technology 2024年第1期29卷 216-231页

作者： Lilong Duan Wei Xue Jun Huang xiao zheng School of Computer Science and Technology Anhui University of TechnologyMaanshan 243032China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China

The problem of imbalanced data classification learning has received much *** classification algorithms are susceptible to data skew to favor majority samples and ignore minority *** weighted minority oversampling technique(MWMOTE)is an effective approach to solve this problem,however,it may suffer from the shortcomings of inadequate noise filtering and synthesizing the same samples as the original minority *** this end,we propose an improved MWMOTE method named joint sample position based noise filtering and mean shift clustering(SPMSC)to solve these ***,in order to effectively eliminate the effect of noisy samples,SPMsC uses a new noise filtering mechanism to determine whether a minority sample is noisy or not based on its position and distribution relative to the majority *** that MWMOTE may generate duplicate samples,we then employ the mean shift algorithm to cluster minority samples to reduce synthetic replicate ***,data cleaning is performed on the processed data to further eliminate class *** on extensive benchmark datasets demonstrate the effectiveness of SPMsC compared with other sampling methods.

关键词： imbalanced data classification oversampling noise filtering clustering

Numerical and experimental study on the falling film flow characteristics with the effect of co-current gas flow in hydrogen liquefaction process

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Petroleum Science 2024年第2期21卷 1369-1384页

作者： Chong-zheng Sun yu-Xing Li Hui Han xiao-yi Geng xiao Lu College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266590ShandongChina College of Pipeline and Civil Engineering/Shandong Provincial Key Laboratory of Oil&Gas Storage and Transportation Safety China University of PetroleumQingdao 266580ShandongChina

Liquid hydrogen storage and transportation is an effective method for large-scale transportation and utilization of hydrogen energy. Revealing the flow mechanism of cryogenic working fluid is the key to optimize heat exchanger structure and hydrogen liquefaction process(LH2). The methods of cryogenic visualization experiment, theoretical analysis and numerical simulation are conducted to study the falling film flow characteristics with the effect of co-current gas flow in LH2spiral wound heat *** results show that the flow rate of mixed refrigerant has a great influence on liquid film spreading process, falling film flow pattern and heat transfer performance. The liquid film of LH2mixed refrigerant with column flow pattern can not uniformly.and completely cover the tube wall surface. As liquid flow rate increases, the falling film flow pattern evolves into sheet-column flow and sheet flow, and liquid film completely covers the surface of tube wall. With the increase of shear effect of gas-phase mixed refrigerant in the same direction, the liquid film gradually becomes unstable, and the flow pattern eventually evolves into a mist flow.

关键词： Hydrogen liquefaction Spiral wound heat exchanger Flow pattern transition Falling film flow

Three-dimensional stress variation characteristics in deep hard rock of CJPL-Ⅱ project based on in-situ monitoring

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International Journal of Mining Science and Technology 2024年第2期34卷 179-195页

作者： Minzong zheng Shaojun Li Zejie Feng Huaisheng Xu yaxun xiao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

In deep hard rock excavation, stress plays a pivotal role in inducing stress-controlled failure. While the impact of excavation-induced stress disturbance on rock failure and tunnel stability has undergone comprehensive examination through laboratory tests and numerical simulations, its validation through insitu stress tests remains unexplored. This study.analyzes the three-dimensional stress changes in the surrounding rock at various depths, monitored during the excavation of B2 Lab in China Jinping Underground Laboratory Phase Ⅱ(CJPL-Ⅱ). The investigation delves into the three-dimensional stress variation characteristics in deep hard rock, encompassing stress components and principal stress. The results indicate changes in both the magnitude and direction of the principal stress during tunnel excavation. To quantitatively describe the degree of stress disturbance, a series of stress evaluation indexes are established based on the distances between stress tensors, including the stress disturbance index(SDI), the principal stress magnitude disturbance index(SDIm), and the principal stress direction disturbance index(SDId). The SDI indicates the greatest stress disturbance in the surrounding rock is 4.5 m from the tunnel wall in B2 Lab. SDIm shows that the principal stress magnitude disturbance peaks at2.5 m from the tunnel wall. SDId reveals that the largest change in principal stress direction does not necessarily occur near the tunnel wall but at a specific depth from it. The established relationship between SDI and the depth of the excavation damaged zone(EDZ) can serve as a criterion for determining the depth of the EDZ in deep hard rock engineering. Additionally, it provides a reference for future construction and support considerations.

关键词： Disturbance stress Tensor distance Stress disturbance index Principal stress direction Underground research laboratory

Unconventional Fluorescent and Multi-responsive Polysiloxane:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第5期42卷 579-590,I0006页

作者： xiao-Di Li Shu-Sheng Li Xu-Bao Jiang xiao-Li Zhu Xiang zheng Kong College of Chemistry.and Chemical Engineering University of JinanJinan250022China College of Chemical Engineering Tianjin UniversityTianjin300072China Foshan(Southern China)Institute for New Materials Foshan528200China

Owing to their high significance in fundamental study.and diverse applications,stimuli-responsive and fluorescent polymers,particularly those with cluster-triggered emission(CTE)featured by non-conjugated chromophores,have drawn tremendous attention in recent *** this work,fluorescent and multi-responsive polysiloxane(FRPS)was synthesized by hydrolytic condensation polymerization of 3-aminopropyl methyl diethoxysilane(APMS)with 3-(N-isopropyl propionamide)iminopropyl methyl diethoxysilane(APMS-NIP),which was formed in situ through aza-Michael addition between APMS and N-isopropyl *** was not only highly sensitive to temperature,pH and CO_(2) in water,but also showed an enhanced and stimuli-adjustable fluorescence *** effects of monomer feeding,pH and CO_(2) on its lower critical solution temperature and fluorescent property were *** fluorescence emission was ascribed to CTE *** addition,FRPS was shown to be highly potential as physiological indicator for cell imaging,and for controlled release and trace detection of *** study provides therefore a type of stimuli-responsive and fluorescent material for potential applications in biomedical fields,and it is also of great significance for understanding of the fluorescence mechanism of polysiloxane-based stimuli-responsive polymers.

关键词： Polysiloxane Multi-responsiveness Cluster-triggered emission Cell imaging Controlled drug release

Advances of biomarkers in nasopharyngeal carcinoma’s early detection

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Science Bulletin 2024年第2期69卷 141-145页

作者： xiao-Hui zheng Allan Hildesheim Wei-Hua Jia State Key Laboratory of Oncology in South China Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060China Costa Rican Agency for Biomedical Investigation INCIENSA FoundationSan Jose 10108Costa Rica

Nasopharyngeal carcinoma(NPC),a highly invasive and metastatic cancer,is widely prevalent in South China,Southeast Asia,and North *** patients with stages I and II are often ***,NPC patients are usually diagnosed with advanced-stage(stages III and IV)at their first *** of NPC at early stage is the key to improve the survival of ***-Barr virus(EBV)plays an essential role in NPC occurrence in endemic ***-based biomarkers,including EBV antibody in serum and EBV DNA in plasma,have been specifically proposed for NPC early ***,we summarize recent advances in biomarkers for the early detection of NPC.

关键词： patients nasopharyngeal Nasopharyngeal

Efficacy of scraping therapy on blood pressure and sleep quality in stage Ⅰ and Ⅱ essential hypertension: A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第1期22卷 12-21页

作者： zheng-gang Zhu Jian-ru Wang xiao-yan Pan School of Nursing Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina School of Health Sciences Universiti Sains MalaysiaKubang Kerian 16150KelantanMalaysia Department of Cardiovascular Medicine the First Affiliated Hospital of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina

Background Scraping therapy is widely used in treating stage I and II essential hypertension in ***,there has been no systematic evaluation of the efficacy of scraping therapy on blood pressure and sleep quality in stage I and II essential *** strategy Seven electronic databases(PubMed,Scopus,Cochrane Library,Web of Science,EBSCO,China National Knowledge Infrastructure and Wanfang Data electronic databases)were searched from inception to December *** on the principle of combining subject words with text words,the search strategy was constructed around search terms for“scraping therapy,”“scraping,”“Guasha,”“Gua sha,”“hypertension,”and“high blood pressure”during the database *** criteria Randomized controlled trials(RCTs)were included if they recruited patients with stage I and II essential hypertension and included a scraping therapy *** intervention group received antihypertensive drugs and scraping therapy,while the control group only took antihypertensive *** extraction and analysis Review Manager 5.4.0 and STATA 15.1 were used to enter all the relevant outcome variables to conduct the *** quality of the selected RCTs was assessed using the PEDro *** sensitivity.analysis was carried out by iteratively excluding individual studies and repeating the analysis to determine the stability of the findings and identify.any studies with greater influence on the *** analysis was performed to find the source of *** plots were used to evaluate the publication bias of included *** Nine RCTs including 765 participants were ***-analysis showed that scraping therapy combined with medication had an advantage over the use of medication alone in lowering systolic blood pressure(mean difference[MD]=?5.09,95%confidence interval[CI]=?6.50 to?3.67,Pysis showed tha

关键词： Scraping therapy Essential hypertension Efficacy Blood pressure Sleep quality Systematic review Meta-analysis

Investigating the elliptic anisotropy of identified particles in p-Pb collisions with a multi-phase transport model

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Nuclear Science and Techniques 2024年第2期35卷 160-169页

作者： Si-yu Tang Liang zheng xiao-Ming Zhang Ren-Zhuo Wan School of Mathematical and Physical Sciences Wuhan Textile UniversityWuhan 430200China School of Mathematics and Physics China University of Geosciences(Wuhan)Wuhan 430074China Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China Hubei Key Laboratory of Digital Textile Equipment Wuhan Textile UniversityWuhan 430200China School of Electronic and Electrical Engineering Wuhan Textile UniversityWuhan 430200China

The elliptic azimuthal anisotropy coefficient(v_(2))of the identified particles at midrapidity(|η|<0.8)was investigated in p-Pb collisions at√s_(NN)=5.02 TeV using a multi-phase transport model(AMPT).The calculatio... 详细信息

The elliptic azimuthal anisotropy coefficient(v_(2))of the identified particles at midrapidity(|η|ystems were extended to a wider transverse momentum(p_(T))range of up to 8 GeV/c for the first *** string-melting version of the AMPT model provides a good description of the measured p_(T)-differential v_(2)of the mesons but exhibits a slight deviation from the baryon v_(2).In addition,we observed the features of mass ordering at low p_(T)and the approximate number-of-constituentquark(NCQ)scaling at intermediate p_(T).Moreover,we demonstrate that hadronic rescattering does not have a significant impact on v_(2)in p-Pb collisions for different centrality selections,whereas partonic scattering dominates in generating the elliptic anisotropy of the final *** study provides further insight into the origin of collective-like behavior in small collision systems and has referential value for future measurements of azimuthal anisotropy.

关键词： Azimuthal anisotropy Small collision systems Transport model