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Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis
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作者 Li Xu Huiming Xu Changyong Tang 《Neural Regeneration Research》 SCIE CAS 2025年第2期354-365,共12页
Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism rem... Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism remains unknown.Therefore,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic targets.Since most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets astrocytes.These experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum disorders.In this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model choices.In addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials. 展开更多
关键词 AQUAPORIN-4 experimental model neuromyelitis optica spectrum disorder PATHOGENESIS
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Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models
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作者 Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models Duc-Dam Nguyen Nguyen Viet Tiep +5 位作者 Quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期467-500,共34页
This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble lear... This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and AB-RBFN.Additionally,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and validation.The models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to roads.These factors were instrumental in predicting the output variable,which was the probability of landslide occurrence.Statistical analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other models.The AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of 0.926.These results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making. 展开更多
关键词 Landslide susceptibility map spatial analysis ensemble modelling information values(IV)
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Global Piecewise Analysis of HIV Model with Bi-Infectious Categories under Ordinary Derivative and Non-Singular Operator with Neural Network Approach
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作者 Ghaliah Alhamzi Badr Saad TAlkahtani +1 位作者 Ravi Shanker Dubey Mati ur Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期609-633,共25页
This study directs the discussion of HIV disease with a novel kind of complex dynamical generalized and piecewise operator in the sense of classical and Atangana Baleanu(AB)derivatives having arbitrary order.The HIV i... This study directs the discussion of HIV disease with a novel kind of complex dynamical generalized and piecewise operator in the sense of classical and Atangana Baleanu(AB)derivatives having arbitrary order.The HIV infection model has a susceptible class,a recovered class,along with a case of infection divided into three sub-different levels or categories and the recovered class.The total time interval is converted into two,which are further investigated for ordinary and fractional order operators of the AB derivative,respectively.The proposed model is tested separately for unique solutions and existence on bi intervals.The numerical solution of the proposed model is treated by the piece-wise numerical iterative scheme of Newtons Polynomial.The proposed method is established for piece-wise derivatives under natural order and non-singular Mittag-Leffler Law.The cross-over or bending characteristics in the dynamical system of HIV are easily examined by the aspect of this research having a memory effect for controlling the said disease.This study uses the neural network(NN)technique to obtain a better set of weights with low residual errors,and the epochs number is considered 1000.The obtained figures represent the approximate solution and absolute error which are tested with NN to train the data accurately. 展开更多
关键词 HIV infection model qualitative scheme approximate solution piecewise global operator neural network
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Prognostic model for esophagogastric variceal rebleeding after endoscopic treatment in liver cirrhosis: A Chinese multicenter study
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作者 Jun-Yi Zhan Jie Chen +7 位作者 Jin-Zhong Yu Fei-Peng Xu Fei-Fei Xing De-Xin Wang Ming-Yan Yang Feng Xing Jian Wang Yong-Ping Mu 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期85-101,共17页
BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and mortality.Despite its clinical importance,recognized p... BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and mortality.Despite its clinical importance,recognized prognostic models that can effectively predict esophagogastric variceal rebleeding in patients with liver cirrhosis are lacking.AIM To construct and externally validate a reliable prognostic model for predicting the occurrence of esophagogastric variceal rebleeding.METHODS This study included 477 EGVB patients across 2 cohorts:The derivation cohort(n=322)and the validation cohort(n=155).The primary outcome was rebleeding events within 1 year.The least absolute shrinkage and selection operator was applied for predictor selection,and multivariate Cox regression analysis was used to construct the prognostic model.Internal validation was performed with bootstrap resampling.We assessed the discrimination,calibration and accuracy of the model,and performed patient risk stratification.RESULTS Six predictors,including albumin and aspartate aminotransferase concentrations,white blood cell count,and the presence of ascites,portal vein thrombosis,and bleeding signs,were selected for the rebleeding event prediction following endoscopic treatment(REPET)model.In predicting rebleeding within 1 year,the REPET model ex-hibited a concordance index of 0.775 and a Brier score of 0.143 in the derivation cohort,alongside 0.862 and 0.127 in the validation cohort.Furthermore,the REPET model revealed a significant difference in rebleeding rates(P<0.01)between low-risk patients and intermediate-to high-risk patients in both cohorts.CONCLUSION We constructed and validated a new prognostic model for variceal rebleeding with excellent predictive per-formance,which will improve the clinical management of rebleeding in EGVB patients. 展开更多
关键词 Esophagogastric variceal bleeding Variceal rebleeding Liver cirrhosis Prognostic model Risk stratification Secondary prophylaxis
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Exploiting fly models to investigate rare human neurological disorders
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作者 Tomomi Tanaka Hyung-Lok Chung 《Neural Regeneration Research》 SCIE CAS 2025年第1期21-28,共8页
Rare neurological diseases,while individually are rare,collectively impact millions globally,leading to diverse and often severe neurological symptoms.Often attributed to genetic mutations that disrupt protein functio... Rare neurological diseases,while individually are rare,collectively impact millions globally,leading to diverse and often severe neurological symptoms.Often attributed to genetic mutations that disrupt protein function or structure,understanding their genetic basis is crucial for accurate diagnosis and targeted therapies.To investigate the underlying pathogenesis of these conditions,researchers often use non-mammalian model organisms,such as Drosophila(fruit flies),which is valued for their genetic manipulability,cost-efficiency,and preservation of genes and biological functions across evolutionary time.Genetic tools available in Drosophila,including CRISPR-Cas9,offer a means to manipulate gene expression,allowing for a deep exploration of the genetic underpinnings of rare neurological diseases.Drosophila boasts a versatile genetic toolkit,rapid generation turnover,and ease of large-scale experimentation,making it an invaluable resource for identifying potential drug candidates.Researchers can expose flies carrying disease-associated mutations to various compounds,rapidly pinpointing promising therapeutic agents for further investigation in mammalian models and,ultimately,clinical trials.In this comprehensive review,we explore rare neurological diseases where fly research has significantly contributed to our understanding of their genetic basis,pathophysiology,and potential therapeutic implications.We discuss rare diseases associated with both neuron-expressed and glial-expressed genes.Specific cases include mutations in CDK19 resulting in epilepsy and developmental delay,mutations in TIAM1 leading to a neurodevelopmental disorder with seizures and language delay,and mutations in IRF2BPL causing seizures,a neurodevelopmental disorder with regression,loss of speech,and abnormal movements.And we explore mutations in EMC1 related to cerebellar atrophy,visual impairment,psychomotor retardation,and gain-of-function mutations in ACOX1 causing Mitchell syndrome.Loss-of-function mutations in ACOX1 result in ACOX1 deficiency,characterized by very-long-chain fatty acid accumulation and glial degeneration.Notably,this review highlights how modeling these diseases in Drosophila has provided valuable insights into their pathophysiology,offering a platform for the rapid identification of potential therapeutic interventions.Rare neurological diseases involve a wide range of expression systems,and sometimes common phenotypes can be found among different genes that cause abnormalities in neurons or glia.Furthermore,mutations within the same gene may result in varying functional outcomes,such as complete loss of function,partial loss of function,or gain-of-function mutations.The phenotypes observed in patients can differ significantly,underscoring the complexity of these conditions.In conclusion,Drosophila represents an indispensable and cost-effective tool for investigating rare neurological diseases.By facilitating the modeling of these conditions,Drosophila contributes to a deeper understanding of their genetic basis,pathophysiology,and potential therapies.This approach accelerates the discovery of promising drug candidates,ultimately benefiting patients affected by these complex and understudied diseases. 展开更多
关键词 ACOX1 Drosophila melanogaster GLIA lipid metabolism model organisms NEUROINFLAMMATION neurologic disorders NEURON rare disease VLCFA
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A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis
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作者 Xiao Liang Xingping Quan +6 位作者 Xiaorui Geng Yujing Huang Yonghua Zhao Lei Xi Zhen Yuan Ping Wang Bin Liu 《Neural Regeneration Research》 SCIE CAS 2025年第7期2029-2037,共9页
To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these me... To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly age-related.In this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed laser.We observed the molding process in mice of different ages and presented age-dependent vascular embolism differentiation.Moreover,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a stroke.Our imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes. 展开更多
关键词 AGE-DEPENDENT cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy PHOTOTHROMBOSIS vascular imaging
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LoRa Sense:Sensing and Optimization of LoRa Link Behavior Using Path-Loss Models in Open-Cast Mines
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作者 Bhanu Pratap Reddy Bhavanam Prashanth Ragam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期425-466,共42页
The Internet of Things(IoT)has orchestrated various domains in numerous applications,contributing significantly to the growth of the smart world,even in regions with low literacy rates,boosting socio-economic developm... The Internet of Things(IoT)has orchestrated various domains in numerous applications,contributing significantly to the growth of the smart world,even in regions with low literacy rates,boosting socio-economic development.This study provides valuable insights into optimizing wireless communication,paving the way for a more connected and productive future in the mining industry.The IoT revolution is advancing across industries,but harsh geometric environments,including open-pit mines,pose unique challenges for reliable communication.The advent of IoT in the mining industry has significantly improved communication for critical operations through the use of Radio Frequency(RF)protocols such as Bluetooth,Wi-Fi,GSM/GPRS,Narrow Band(NB)-IoT,SigFox,ZigBee,and Long Range Wireless Area Network(LoRaWAN).This study addresses the optimization of network implementations by comparing two leading free-spreading IoT-based RF protocols such as ZigBee and LoRaWAN.Intensive field tests are conducted in various opencast mines to investigate coverage potential and signal attenuation.ZigBee is tested in the Tadicherla open-cast coal mine in India.Similarly,LoRaWAN field tests are conducted at one of the associated cement companies(ACC)in the limestone mine in Bargarh,India,covering both Indoor-toOutdoor(I2O)and Outdoor-to-Outdoor(O2O)environments.A robust framework of path-loss models,referred to as Free space,Egli,Okumura-Hata,Cost231-Hata and Ericsson models,combined with key performance metrics,is employed to evaluate the patterns of signal attenuation.Extensive field testing and careful data analysis revealed that the Egli model is the most consistent path-loss model for the ZigBee protocol in an I2O environment,with a coefficient of determination(R^(2))of 0.907,balanced error metrics such as Normalized Root Mean Square Error(NRMSE)of 0.030,Mean Square Error(MSE)of 4.950,Mean Absolute Percentage Error(MAPE)of 0.249 and Scatter Index(SI)of 2.723.In the O2O scenario,the Ericsson model showed superior performance,with the highest R^(2)value of 0.959,supported by strong correlation metrics:NRMSE of 0.026,MSE of 8.685,MAPE of 0.685,Mean Absolute Deviation(MAD)of 20.839 and SI of 2.194.For the LoRaWAN protocol,the Cost-231 model achieved the highest R^(2)value of 0.921 in the I2O scenario,complemented by the lowest metrics:NRMSE of 0.018,MSE of 1.324,MAPE of 0.217,MAD of 9.218 and SI of 1.238.In the O2O environment,the Okumura-Hata model achieved the highest R^(2)value of 0.978,indicating a strong fit with metrics NRMSE of 0.047,MSE of 27.807,MAPE of 27.494,MAD of 37.287 and SI of 3.927.This advancement in reliable communication networks promises to transform the opencast landscape into networked signal attenuation.These results support decision-making for mining needs and ensure reliable communications even in the face of formidable obstacles. 展开更多
关键词 Internet of things long range wireless area network ZigBee mining environments path-loss models coefficient of determination mean square error
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Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology
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作者 Yiyang Qin Wenzhen Zhu +6 位作者 Tingting Guo Yiran Zhang Tingting Xing Peng Yin Shihua Li Xiao-Jiang Li Su Yang 《Neural Regeneration Research》 SCIE CAS 2025年第9期2655-2666,共12页
Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen r... Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy patients.These aggregates alter protein-protein interactions and compromise transcriptional activity.In this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic factor.Overexpressio n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor aggregation.Conversely.knocking down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor aggregation.Our findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy. 展开更多
关键词 androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model NEURODEGENERATION neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor
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Physiology and health assessment,risk balance,and model for endstage liver disease scores:Postoperative outcome of liver transplantation
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作者 Raquel Hohenreuther Andresa ThoméSilveira +4 位作者 Edison Moraes Rodrigues Filho Anderson Garcez Bruna Goularth Lacerda Sabrina Alves Fernandes Claudio Augusto Marroni 《World Journal of Transplantation》 2025年第1期86-94,共9页
BACKGROUND Liver transplantation aims to increase the survival of patients with end-stage liver diseases and improve their quality of life.The number of organs available for transplantation is lower than the demand.To... BACKGROUND Liver transplantation aims to increase the survival of patients with end-stage liver diseases and improve their quality of life.The number of organs available for transplantation is lower than the demand.To provide fair organ distribution,predictive mortality scores have been developed.AIM To compare the Acute Physiology and Chronic Health Evaluation IV(APACHE IV),balance of risk(BAR),and model for end-stage liver disease(MELD)scores as predictors of mortality.METHODS Retrospective cohort study,which included 283 adult patients in the postoperative period of deceased donor liver transplantation from 2014 to 2018.RESULTS The transplant recipients were mainly male,with a mean age of 58.1 years.Donors were mostly male,with a mean age of 41.6 years.The median cold ischemia time was 3.1 hours,and the median intensive care unit stay was 5 days.For APACHE IV,a mean of 59.6 was found,BAR 10.7,and MELD 24.2.The 28-day mortality rate was 9.5%,and at 90 days,it was 3.5%.The 28-day mortality prediction for APACHE IV was very good[area under the curve(AUC):0.85,P<0.001,95%CI:0.76-0.94],P<0.001,BAR(AUC:0.70,P<0.001,95%CI:0.58–0.81),and MELD(AUC:0.66,P<0.006,95%CI:0.55-0.78),P<0.008.At 90 days,the data for APACHE IV were very good(AUC:0.80,P<0.001,95%CI:0.71–0.90)and moderate for BAR and MELD,respectively,(AUC:0.66,P<0.004,95%CI:0.55–0.77),(AUC:0.62,P<0.026,95%CI:0.51–0.72).All showed good discrimination between deaths and survivors.As for the best value for liver transplantation,it was significant only for APACHE IV(P<0.001).CONCLUSION The APACHE IV assessment score was more accurate than BAR and MELD in predicting mortality in deceased donor liver transplant recipients. 展开更多
关键词 Liver transplantation Acute physiology and chronic health evaluation IV Balance of risk model for end-stage liver disease MORTALITY Intensive care unit
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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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两种新的push-pull平衡的大数据量无线传感器网络数据分发算法 被引量:5
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作者 陶孜谨 龚正虎 卢泽新 《计算机研究与发展》 EI CSCD 北大核心 2008年第7期1115-1125,共11页
无线传感器网络中如何获得较低的通信代价同时在事件数据的push和pull之间实现更好的平衡是各种数据分发算法共同追求的目标.分析了目前已公认较好的两种典型的有结构和无结构的数据分发算法,指出了它们的优缺点.在此基础上,结合这两种... 无线传感器网络中如何获得较低的通信代价同时在事件数据的push和pull之间实现更好的平衡是各种数据分发算法共同追求的目标.分析了目前已公认较好的两种典型的有结构和无结构的数据分发算法,指出了它们的优缺点.在此基础上,结合这两种算法使用的push-pull策略,针对不同应用环境下的无线传感器网络的ALL型查询的特定需求,提出了两种基于有结构和无结构存储模式相结合的混合型数据分发算法,分别是Hybrid-Dcs-Cn1(HDC1)算法和Hybrid-Dcs-Cn2(HDC2)算法.分析表明这两种算法在保证push-pull之间平衡的前提下解决了已有算法存在的热点问题:存储拷贝数多和查询性能低,能更好地适应传感器网络的特点,是两种能量高效的数据分发算法. 展开更多
关键词 数据分发 push-pull平衡 热点 通信代价 负载均衡 无线传感器网络
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Push-Pull型pFLASH开关单元结构设计及特性
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作者 刘国柱 洪根深 +5 位作者 于宗光 赵文彬 曹利超 吴素贞 李燕妃 李冰 《半导体技术》 CAS CSCD 北大核心 2018年第9期652-658,663,共8页
基于90 nm eFLASH工艺设计并制备了一种新型抗辐照Push-Pull型pFLASH开关单元,并对其特性进行了研究。该结构由2个2T-FLASH管(T1/T2)和1个信号传输PMOS管(T3)组成,采用带带隧穿(BTBT)编程方式和福勒-诺德海姆(FN)擦除方式实现... 基于90 nm eFLASH工艺设计并制备了一种新型抗辐照Push-Pull型pFLASH开关单元,并对其特性进行了研究。该结构由2个2T-FLASH管(T1/T2)和1个信号传输PMOS管(T3)组成,采用带带隧穿(BTBT)编程方式和福勒-诺德海姆(FN)擦除方式实现其"开/关"态功能。同时,对其"开/关"态特性进行表征,研究其耐久性和电荷保持特性,最后,对其抗总剂量(TID)能力进行评估。实验结果表明:该器件的"T1编程-T2擦除"与"T1擦除-T2编程"态均可以实现信号传输管的"开/关"态功能,其阈值窗口的均值约为10.5 V;在工作电压为-1.2 V条件下,T3管的"开"态驱动电流均值约为0.92 mA,"关"态漏电流低于40 pA,且均表现出了良好的一致性。同时,该器件的循环擦/写次数可达10 000次,在25℃的"开/关"态应力条件下寿命大于10年,抗总剂量能力可达150 krad(Si)以上。 展开更多
关键词 push-pull型pFLASH开关单元 “开/关”态 阈值窗口 电荷保持性 总剂量(TID)
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基于第三方的Push-Pull逆向物流模式
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作者 于建红 鲁耀斌 《管理学报》 2005年第z1期174-177,共4页
首先阐述了逆向物流的内涵、功能以及基于第三方逆向物流的提出,其次分析了外包逆向物流的优势,最后分析了生产控制系统中的Push-Pull方法.在此基础上,提出基于第三方的Push-Pull逆向物流模式.
关键词 逆向物流 第三方逆向物流 push-pull
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基于DTN网络的PUSH-PULL策略研究
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作者 崔永锋 《河南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第6期54-56,共3页
DTN网络是新一代的网络体系结构,PUSH-PULL是解决DTN网络中拥塞控制的一种有效策略,介绍了DTN网络中拥塞控制的研究现状,并对PUSH-PULL的各个策略进行了阐述,通过NS2搭建DTN网络环境并通过模拟对PUSH-PULL的7种策略进行仿真,模拟仿真结... DTN网络是新一代的网络体系结构,PUSH-PULL是解决DTN网络中拥塞控制的一种有效策略,介绍了DTN网络中拥塞控制的研究现状,并对PUSH-PULL的各个策略进行了阐述,通过NS2搭建DTN网络环境并通过模拟对PUSH-PULL的7种策略进行仿真,模拟仿真结果表明,采用PUSH-PULL策略的可以有效的提高信息的传输率. 展开更多
关键词 DTN push-pull NS2 仿真
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高并发数据共享系统基于Push-Pull混合模式的性能优化
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作者 王子光 王子明 《现代信息科技》 2018年第4期65-67,共3页
随着面向服务架构的大规模分布式系统的应用,多个系统之间由于数据集成的需要,彼此间要高并发传递大量数据,特别是状态数据的同步,对数据的实时性要求越来越高。数据单纯通过客户端以Pull(拉取)模式获取已经不能满足实时性要求,高频率... 随着面向服务架构的大规模分布式系统的应用,多个系统之间由于数据集成的需要,彼此间要高并发传递大量数据,特别是状态数据的同步,对数据的实时性要求越来越高。数据单纯通过客户端以Pull(拉取)模式获取已经不能满足实时性要求,高频率服务调用也会给服务端数据库带来较大的压力。单纯通过服务端以Push(推送)模式推送给客户端也不能满足客户端对个性化数据的需求,大量推送既会给服务端带来较大压力,又会造成客户端数据处理不及时。本文针对高并发数据共享系统应用过程中产生的性能问题,提出一种基于pub/sub消息处理的Push-Pull混合模式优化方案,实践表明该方案极大地提高了系统可用性及数据安全性,对同类系统的性能优化具有较好的借鉴作用。 展开更多
关键词 高并发 数据共享系统 性能优化 pub/sub消息处理 push-pull混合模式
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采用STAMP-24Model的多组织事故分析
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作者 曾明荣 秦永莹 +2 位作者 刘小航 栗婧 尚长岭 《安全与环境学报》 CAS CSCD 北大核心 2024年第7期2741-2750,共10页
安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事... 安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事故分析的方法,并以青岛石油爆炸事故为例进行事故原因分析。结果显示:STAMP-24Model可以分组织,分层次且有效、全面、详细地分析涉及多个组织的事故原因,探究多组织之间的交互关系;对事故进行动态演化分析,可得到各组织不安全动作耦合关系与形成的事故失效链及管控失效路径,进而为预防多组织事故提供思路和参考。 展开更多
关键词 安全工程 系统理论事故建模与过程模型(STAMP) 24model 多组织事故 原因分析
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基于改进24Model-ISM-SNA建筑工人不安全行为关联路径研究
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作者 赵平 刘钰 +1 位作者 靳丽艳 王佳慧 《工业安全与环保》 2024年第7期37-40,共4页
建筑施工现场环境复杂,为有效控制不安全行为发生,基于行为安全“2-4”模型对360份具有代表性的建筑安全事故调查报告进行分析,提取出22个不安全行为的主要影响因素。利用灰色关联分析方法(GRA)改进的集成ISM-SNA模型,将不安全行为风险... 建筑施工现场环境复杂,为有效控制不安全行为发生,基于行为安全“2-4”模型对360份具有代表性的建筑安全事故调查报告进行分析,提取出22个不安全行为的主要影响因素。利用灰色关联分析方法(GRA)改进的集成ISM-SNA模型,将不安全行为风险因素划分为表层、过渡层与深层,然后对风险因素进行可视化分析、中心度分析及凝聚子群分析,揭示了各致因因素间的关联关系和传导路径。结果表明,建筑工人不安全行为影响因素可划分成7级3阶的多级递阶结构,安全意识、现场监管、外部环境是建筑工人不安全行为的关键影响因素,同时现场监管和隐患排查到位能有效降低不安全行为的发生。 展开更多
关键词 建筑工人 不安全行为 24model 解释结构模型(ISM) 社会网络分析(SNA)
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基于24Model的地铁内涝事故原因分析与评估
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作者 张江石 胡馨月 +3 位作者 侯轩 李泳暾 李梓萌 高进东 《安全与环境工程》 CAS CSCD 北大核心 2024年第6期111-117,共7页
为降低地铁内涝事故灾害风险,基于事故致因“2-4”模型,分析了地铁内涝事故致灾因子,采用层次分析法构建了地铁内涝事故原因分析指标体系,确定了各风险因子的权重,并利用模糊综合评价法对地铁内涝事故进行了定量评估,识别出关键的影响... 为降低地铁内涝事故灾害风险,基于事故致因“2-4”模型,分析了地铁内涝事故致灾因子,采用层次分析法构建了地铁内涝事故原因分析指标体系,确定了各风险因子的权重,并利用模糊综合评价法对地铁内涝事故进行了定量评估,识别出关键的影响因素。结果表明:地铁内涝事故一级指标中不安全动作与物态因素最重要,其中影响最大的指标包括擅自更改建筑设计、未按照要求检查水位情况、未及时排水、出入口不符合防汛标准等因素;习惯性不安全行为的权重位居第二,表明该指标因素较为重要,同时安全管理体系得分位居第二,表明该指标因素较易发生。对关键指标采取防范措施,可有效降低风险,从而减少地铁内涝事故的发生。 展开更多
关键词 安全工程 地铁内涝 24model 层次分析法 模糊综合评价法
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基于24Model-D-ISM的地铁站火灾疏散影响因素研究
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作者 孙世梅 张家严 《中国安全科学学报》 CAS CSCD 北大核心 2024年第4期153-159,共7页
为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾... 为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾人员疏散影响因素指标体系;采用算子客观赋权法(C-OWA)改进决策试验与评价实验法(DEMATEL),确定地铁站火灾人员疏散的重要影响因素;在此基础上,采用解释结构模型(ISM)分析各个因素间的层次结构及相互作用路径,构建地铁站火灾人员疏散影响因素的多级递阶结构模型。研究结果表明:疏散引导、恐慌从众行为、人员拥挤为地铁站火灾人员疏散的关键影响因素;地铁站火灾人员疏散受表层因素、中间层因素、深层因素共同作用的影响,其中,疏散教育与培训、设施维护与检查、疏散预案等因素是根源影响因素,重视根源影响因素的改善有利于从本质上预防和控制事故的发生。 展开更多
关键词 “2-4”模型(24model) 决策试验与评价实验法(DEMATEL) 解释结构模型(ISM) 地铁站 火灾疏散 影响因素
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Push-Pull型不对称钴(III)咔咯的合成与性质 被引量:1
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作者 张振 温俊霞 +2 位作者 张生玉 朱卫华 梁旭 《合成化学》 CAS 北大核心 2020年第9期759-763,共5页
酸催化下,在水-甲醇体系中,合成并分离了3种含有Push-Pull取代基的新型低对称A2B型钴(III)咔咯,其结构经1H NMR,19F NMR和HR-MS(ESI-TOF)表征。并利用光谱学和电化学方法对3种钴咔咯的电子结构进行了深入研究。结果表明:引入Push-Pull... 酸催化下,在水-甲醇体系中,合成并分离了3种含有Push-Pull取代基的新型低对称A2B型钴(III)咔咯,其结构经1H NMR,19F NMR和HR-MS(ESI-TOF)表征。并利用光谱学和电化学方法对3种钴咔咯的电子结构进行了深入研究。结果表明:引入Push-Pull型不对称对钴(III)咔咯分子的电子结构有明显的调控作用,且随着引入基团的改变而产生显著的规律性差异,为进一步的分子设计、合成及其应用奠定基础。 展开更多
关键词 push-pull型咔咯 光谱性质 电化学性质 电子结构 合成
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