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Cluster DetectionMethod of Endogenous Security Abnormal Attack Behavior in Air Traffic Control Network

Computers, Materials & Continua 2024年第5期79卷 2523-2546页

作者： Ruchun jia jianwei zhang Yi Lin Yunxiang Han Feike Yang College of Computer Science Sichuan UniversityChengdu610065China Equipment Management and Unmanned Aerial Vehicle College of Air Force Engineering University Air Force Engineering UniversityXi’an710051China

In order to enhance the accuracy of Air Traffic Control(ATC)cybersecurity attack detection,in this paper,a new clustering detection method is designed for air traffic control network security *** feature set for ATC cybersecurity attacks is constructed by setting the feature states,adding recursive features,and determining the feature *** expected information gain and entropy of the feature data are computed to determine the information gain of the feature data and reduce the interference of similar feature *** autoencoder is introduced into the AI(artificial intelligence)algorithm to encode and decode the characteristics of ATC network security attack behavior to reduce the dimensionality of the ATC network security attack behavior *** on the above processing,an unsupervised learning algorithm for clustering detection of ATC network security attacks is ***,determine the distance between the clustering clusters of ATC network security attack behavior characteristics,calculate the clustering threshold,and construct the initial clustering ***,the new average value of all feature objects in each cluster is recalculated as the new cluster ***,it traverses all objects in a cluster of ATC network security attack behavior feature ***,the cluster detection of ATC network security attack behavior is completed by the computation of objective *** experiment took three groups of experimental attack behavior data sets as the test object,and took the detection rate,false detection rate and recall rate as the test indicators,and selected three similar methods for comparative *** experimental results show that the detection rate of this method is about 98%,the false positive rate is below 1%,and the recall rate is above 97%.Research shows that this method can improve the detection performance of security attacks in air traffic control network.

关键词： Air traffic control network security attack behavior cluster detection behavioral characteristics information gain cluster threshold automatic encoder

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Defect recognition of oil-pressboard insulation based on frequent arc reignition phenomenon under switching impulse voltage

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High Voltage 2024年第4期9卷 773-785页

作者： Simeng Li Yukun zhang Yunfei jia Shengchang Ji Yanhua Han Wensen Wang State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi'an Jiaotong UniversityXi'anChina State Grid Shaanxi Electric Power Research Institute Xi'anChina

In the past three years,a number of oil-immersed ultra-high-voltage shunt reactors have experienced discharge defects when being put into operation,resulting in an overload of ***,detecting and identifying these discharge defects caused by switching impulse voltage is challenging under steady-state *** poses unpredictable and difficult-to-assess safety risks for the longterm operation of the equipment and subsequent transient ***,comprehending the discharge behavior of oilpressboard(PB)insulation under switching impulse voltage and devising a method to identify defects becomes *** study focuses on investigating the frequent arc reignition(FAR)pattern exhibited by typical defects under both standard and oscillation switching impulse *** objective is to uncover the mechanism behind FAR and propose a defect recognition strategy suitable for transient *** study reveals the FAR process will occur at least once during the breakdown process;the FAR phenomenon is the weakest in the surface defect with a weak vertical electric *** average recovery voltage percentage and the average discharge interval of the FAR process decrease with increasing impulse amplitude or oscillation ***,the average number of discharges decreases with higher oscillation frequency,while it initially increases and then decreases with increaseing *** on the analysis of the number of FAR processes and their variation in terms of amplitude or discharge interval,a method for recognizing oil-PB defects during switching transient processes is developed and successfully applied to a case study involving acetylene overload in a 1000 kV shunt reactor.

关键词： field. insulation oscillation

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Colonoscopy-assisted removal of an impaction foreign body at the rectosigmoid junction: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1990-1995页

作者： Peng-Fei Zhou Jin-Gen Lu jia-Dong zhang jia-Wen Wang Department of Anorectal Surgery Longhua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200000China

BACKGROUND When an anorectal foreign body is found,its composition and shape should be evaluated,and a timely and effective treatment plan should be developed based on the patient's symptoms to avoid serious complications such as intestinal perforation caused by displacement of the foreign *** SUMMARY A 54-year-old male was admitted to our outpatient clinic on June 3,2023,due to a rectal foreign body that had been embedded for more than 24 *** patient reported using a glass electrode tube to assist in the recovery of prolapsed hemorrhoids,however,the electrode tube was inadvertently inserted into the anus and could not be removed by the *** hospitalization,the patient underwent surgery,and the foreign body was dragged into the rectum with the aid of *** anus was dilated with a comb-type pulling hook and an anal fistula pulling hook to widen the anus and remove the foreign body,and the local anal symptoms were then relieved with topical *** patient was allowed to eat and drink,and an entire abdominal Computed tomography(CT)and colonoscopy were reviewed 3 d after *** revealed no foreign body residue and colonoscopy showed no metal or other residues in the colon and rectum,and no apparent intestinal tract *** The timeliness and rationality of the surgical and therapeutic options for this patient were based on a literature review of the clinical signs and conceivable conditions in such *** type,material and the potential risks of rectal foreign bodies should be considered.

关键词： Foreign body impaction Surgical therapy Rectum-sigmoid colon Colonoscopy Case report

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Highly effective self-assembled porphyrin MOCs nanomaterials for enhanced photodynamic therapy in tumor

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Chinese Chemical Letters 2024年第5期35卷 302-306页

作者： Yihao zhang Yang jiao Xianchao jia Qiaojia Guo Chunying Duan School of Chemistry Dalian University of TechnologyDalian 116024China State Key Laboratory of Fine Chemicals School of ChemistryDalian University of TechnologyDalian 116024China

Porphyrins and their derivatives are excellent photosensitizers in photodynamic therapy(PDT).The modification of porphyrin molecules into metal-organic cages(MOCs)is a viable strategy to improve their *** this work,MOC C66 based on porphyrin was synthesised by a one-pot self-assembly *** three-dimensional structure of the metal-organic cage ameliorated the aggregation and selfquenching of porphyrins and increased the molar absorption coefficient in the visible light region,which enhanced the reactive oxygen species(ROS)yield of porphyrins and effectively improved the efficiency of photodynamic *** generation ability tests in solution confirmed the improved reactive oxygen capacity of the cage,which showed greater phototoxicity to HeLa and MCF-7 cells in vitro,suggesting a new strategy for future modifications of the simple synthesis of porphyrins as photosensitizers.

关键词： Metal-organic cage Porphyrin Photodynamic therapy Reactive oxygen species Nanoparticles

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Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow

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Petroleum Science 2024年第1期21卷 343-351页

作者： Yang Wang jia zhang Shi-Long Yang Ze-Xuan Xu Shi-Qing Cheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil *** contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective ***,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant *** this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer *** hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer *** combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir *** with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore *** field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and th

关键词： Polymer flooding Non-Newtonian fluid Non-uniform fracture conductivity Two-phase flow Pressure transient analysis

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Time-sensitive prediction of NO_(2) concentration in China using an ensemble machine learning model from multi-source data

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Journal of Environmental Sciences 2024年第3期137卷 30-40页

作者： Chenliang Tao Man jia Guoqiang Wang Yuqiang zhang Qingzhu zhang Xianfeng Wang Qiao Wang Wenxing Wang Big Data Research Center for Ecology and Environment Environment Research InstituteShandong UniversityQingdao 266237China Shandong Provincial Eco-environment Monitoring Center Jinan 250101China

Nitrogen dioxide(NO_(2))poses a critical potential risk to environmental quality and public health.A reliable machine learning(ML)forecasting framework will be useful to provide valuable information to support government *** on the data from1609 air quality monitors across China from 2014-2020,this study designed an ensemble ML model by integrating multiple types of spatial-temporal variables and three sub-models for time-sensitive prediction over a wide *** ensemble ML model incorporates a residual connection to the gated recurrent unit(GRU)network and adopts the advantage of Transformer,extreme gradient boosting(XGBoost)and GRU with residual connection network,resulting in a 4.1%±1.0%lower root mean square error over XGBoost for the test *** ensemble model shows great prediction performance,with coefficient of determination of 0.91,0.86,and 0.77 for 1-hr,3-hr,and 24-hr averages for the test results,*** particular,this model has achieved excellent performance with low spatial uncertainty in Central,East,and North China,the major site-dense *** the interpretability analysis based on the Shapley value for different temporal resolutions,we found that the contribution of atmospheric chemical processes is more important for hourly predictions compared with the daily scale predictions,while the impact of meteorological conditions would be ever-prominent for the *** with existing models for different spatiotemporal scales,the present model can be implemented at any air quality monitoring station across China to facilitate achieving rapid and dependable forecast of NO_(2),which will help developing effective control policies.

关键词： Air quality prediction Deep learning Ensemble method Nitrogen dioxide Spatiotemporal covariates

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Changes of growth-climate relationships of Smith fir forests along an altitudinal gradient

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Journal of Forestry Research 2024年第5期35卷 37-46页

作者： jiacheng Zheng Jing Yang Hengfeng jia Lixin Lyu jiayang Langzhen Qi-Bin zhang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Linzhou Bureau of Meteorology LinzhouLhasa 851611TibetPeople’s Republic of China Institute of Plateau Ecology Tibet Agricultural and Animal Husbandry UniversityLinzhi 860000TibetPeople’s Republic of China

Temporal changes in the relationship between tree growth and climate have been observed in numerous forests across the *** patterns and the possible regu-lators(e.g.,forest community structure)of such changes are,however,not well understood.A vegetation survey and analyses of growth-climate relationships for Abies georgei ***(Smith fir)forests were carried along an altitudi-nal gradient from 3600 to 4200 m on Meili Snow Mountain,southeastern Tibetan *** results showed that the associations between growth and temperature have declined since the 1970s over the whole transect,while response to standardized precipitation-evapotranspiration indices(SPEI)strengthened in the mid-and *** between growth and vegetation data showed that tree growth was more sensitive to drought in stands with higher species richness and greater shrub *** stress on growth may be increased by heavy competition from shrub and herb *** results show the non-stationary nature of tree growth-climate associations and the linkage to for-est community *** components should be considered in future modeling and forecasting of forest dynamics in relation to climate changes.

关键词： Climate change Tree rings Altitudinal gradient Community structure Plant diversity

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CRISPR-Cas9-based genome-editing technologies in engineering bacteria for the production of plant-derived terpenoids

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Engineering Microbiology 2024年第3期4卷 43-53页

作者： Xin Sun Haobin zhang Yuping jia Jingyi Li Meirong jia State Key Laboratory of Bioactive Substance and Function of Natural Medicines NHC Key Laboratory of Biosynthesis of Natural ProductsCAMS Key Laboratory of Enzyme and Biocatalysis of Natural DrugsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Shandong Academy of Pharmaceutical Sciences Jinan 250101China

Terpenoids are widely used as medicines,flavors,and ***,the use of these natural products is largely restricted by their low abundance in native ***,heterologous biosynthesis of terpenoids in microorganisms offers an alternative and sustainable approach for efficient *** genome-editing technologies have been developed for microbial strain *** regularly interspaced short palin-dromic repeats(CRISPR)-CRISPR associated protein 9(Cas9)is the most commonly used system owing to its outstanding efficiency and convenience in genome *** this review,the basic principles of CRISPR-Cas9 systems are briefly introduced and their applications in engineering bacteria for the production of plant-derived terpenoids are *** aim of this review is to provide an overview of the current developments of CRISPR-Cas9-based genome-editing technologies in bacterial engineering,concluding with perspectives on the challenges and opportunities of these technologies.

关键词： CRISPR-Cas9 Genome editing Terpenoids Metabolic engineering Bacteria

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Effects of serum inflammatory factors,health index and disease activity scores on ankylosing spondylitis patients with sleep disorder

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World Journal of Psychiatry 2024年第6期14卷 866-875页

作者： Hui Wang jia-Ying Sun Yue zhang Department of Rheumatology and Immunology The First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina

BACKGROUND Patients with ankylosing spondylitis(AS)frequently suffer from comorbid sleep disorders,exacerbating the burden of the disease and affecting their quality of *** To investigate the clinical significance of serum inflammatory factors,health index and disease activity scores in patients with AS complicated by sleep *** A total of 106 AS patients with comorbid sleep disorders were included in the *** patients were grouped into the desirable and undesirable prognosis groups in accordance with their clinical *** serum levels of inflammatory factors,including C-reactive protein,erythrocyte sedimentation rate,interleukin(IL)-6,tumour necrosis factor-αand IL-1β,were *** activity scores,such as the Bath AS functional index,Bath AS disease activity index,Bath AS metrology index and AS disease activity score,were *** health index was obtained through the Short Form-36 *** The study found significant associations amongst serum inflammatory factors,health index and disease activity scores in AS patients with comorbid sleep *** correlations were found between serum inflammatory factors and disease activity scores,indicating the influence of heightened systemic inflammation on disease severity and functional ***,negative correlations were found between disease activity scores and health index parameters,highlighting the effect of disease activity on various aspects of healthrelated quality of *** regression analysis further confirmed the predictive value of these factors on patient outcomes,underscoring their potential utility in risk assessment and *** The findings demonstrate the intricate interplay amongst disease activity,systemic inflammation and patientreported health outcomes in AS patients complicated by sleep *** results emphasise the need for comprehensive care strategies that address the diverse needs and challe

关键词： Inflammatory factors Disease activity scores Health index Ankylosing spondylitis Sleep disorders

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Voluntary wheel running ameliorated the deleterious effects of high-fat diet on glucose metabolism,gut microbiota and microbial-associated metabolites

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Food Science and Human Wellness 2024年第3期13卷 1672-1684页

作者： Ling zhang Wenyu Zou Yongyan Hu Honghua Wu Ying Gao Junqing zhang jia Zheng Department of Endocrinology Peking University First HospitalBeijing 100034China Laboratory Animal Facility Peking University First HospitalBeijing 100034China

Exercise training is critical for the early prevention and treatment of obesity and diabetes ***,the mechanism with gut microbiota and fecal metabolites underlying the effects of voluntary wheel running on high-fat diet induced abnormal glucose metabolism has not been fully elaborated.C57BL/6 male mice were randomly assigned to 4 groups according to diets(fed with normal chow diet or high-fat diet)and running paradigm(housed in static cage or with voluntary running wheel).An integrative 16S rDNA sequencing and metabolites profiling was synchronously performed to characterize the effects of voluntary wheel running on gut microbiota and *** showed that voluntary wheel running prevented the detrimental effects of high-fat feeding on glucose metabolism 16S rDNA sequencing showed remarkable changes in Rikenella and Marvinbryantia *** profiling indicated multiple altered metabolites,which were enriched in secondary bile acid biosynthesis *** conclusion,our study indicated that voluntary wheel running significantly improved glucose metabolism and counteracted the deleterious effects of high-fat feeding on body weight and glucose *** further found that voluntary wheel running could integratively program gut microbiota composition and fecal metabolites changes,and may regulate muricholic acid metabolism and secondary bile acid biosynthesis in high-fat fed mice.

关键词： High-fat diet Voluntary wheel running Gut microbiota Metabolomics Glucose metabolism

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