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Evolution of Satellite Communication Systems Toward 5G/6G for 2030 and Beyond
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作者 Afang Yuan Zhihua Yang Zhili Sun 《Engineering》 2025年第11期35-41,共7页
1.Introduction From the first-generation(1G)through the second-generation(2G)Global System for Mobile Communications(GSM),the third-generation(3G)wideband code division multiple access(WCDMA)to the fourth-generation(4... 1.Introduction From the first-generation(1G)through the second-generation(2G)Global System for Mobile Communications(GSM),the third-generation(3G)wideband code division multiple access(WCDMA)to the fourth-generation(4G)long-term evolution(LTE)wireless networks,terrestrial networks(TNs)have demonstrated significant success in increasing communication speeds and improving quality of service(QoS)for users. 展开更多
关键词 communication speeds G satellite communication EVOLUTION code division multiple access wcdma system mobile communications gsm networksterrestrial networks tns quality service
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Endoscopic pancreatic duct stent placement for inflammatory pancreatic diseases 被引量:4
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作者 Pier Alberto Testoni 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第45期5971-5978,共8页
The role of endoscopic therapy in the management of pancreatic diseases is continuously evolving; at present most pathological conditions of the pancreas are successfully treated by endoscopic retrograde cholangio- pa... The role of endoscopic therapy in the management of pancreatic diseases is continuously evolving; at present most pathological conditions of the pancreas are successfully treated by endoscopic retrograde cholangio- pancreatography (ERCP) or endoscopic ultrasound (EUS), or both. Endoscopic placement of stents has played and still plays a major role in the treatment of chronic pancreatitis, pseudocysts, pancreas divisum, main pancreatic duct injuries, pancreatic fistulae, complications of acute pancreatitis, recurrent idiopathic pancreatitis, and in the prevention of post-ERCP pancreatitis. These stents are currently routinely placed to reduce intraductal hypertension, bypass obstructing stones, restore lumen patency in cases with dominant, symptomatic strictures, seal main pancreatic duct disruption, drain pseudocysts or fluid collections, treat symptomatic major or minor papilla sphincter stenosis, and prevent procedure-induced acute pancreatitis. The present review aims at updating and discussing techniques, indications, and results of endoscopic pancreatic duct stent placement in acute and chronic inflammatory diseases of the pancreas. 展开更多
关键词 Chronic pancreatitis Pancreas divisum Pancreatic pseudocyst Pancreatic fistulas Idiopathicrecurrent pancreatitis Main pancreatic duct stenting Pancreatic dorsal duct stenting
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Integration of wearable electronics and heart rate variability for human physical and mental well-being assessment
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作者 Feifei Yin Jian Chen +4 位作者 Haiying Xue Kai Kang Can Lu Xinyi Chen Yang Li 《Journal of Semiconductors》 2025年第1期58-76,共19页
Heart rate variability(HRV)that can reflect the dynamic balance between the sympathetic nervous and parasympathetic nervous of human autonomic nervous system(ANS)has attracted considerable attention.However,traditiona... Heart rate variability(HRV)that can reflect the dynamic balance between the sympathetic nervous and parasympathetic nervous of human autonomic nervous system(ANS)has attracted considerable attention.However,traditional electrocardiogram(ECG)devices for HRV analysis are bulky,and hard wires are needed to attach measuring electrodes to the chest,resulting in the poor wearable experience during the long-term measurement.Compared with that,wearable electronics enabling continuously cardiac signals monitoring and HRV assessment provide a desirable and promising approach for helping subjects determine sleeping issues,cardiovascular diseases,or other threats to physical and mental well-being.Until now,significant progress and advances have been achieved in wearable electronics for HRV monitoring and applications for predicting human physical and mental well-being.In this review,the latest progress in the integration of wearable electronics and HRV analysis as well as practical applications in assessment of human physical and mental health are included.The commonly used methods and physiological signals for HRV analysis are briefly summarized.Furthermore,we highlighted the research on wearable electronics concerning HRV assessment and diverse applications such as stress estimation,drowsiness detection,etc.Lastly,the current limitations of the integrated wearable HRV system are concluded,and possible solutions in such a research direction are outlined. 展开更多
关键词 wearable electronics HRV analysis physical and mental well-being machine learning stress detection
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An Unprecedented Efficiency with Approaching 21%Enabled by Additive‑Assisted Layer‑by‑Layer Processing in Organic Solar Cells 被引量:1
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作者 Shuai Xu Youdi Zhang +6 位作者 Yanna Sun Pei Cheng Zhaoyang Yao Ning Li Long Ye Lijian Zuo Ke Gao 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期372-375,共4页
Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network act... Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network active layer morphology,featuring a bulk p-in structure and proper vertical segregation achieved through additive-assisted layer-by-layer deposition.This optimized hierarchical gradient fibrillar morphology and optical management synergistically facilitates exciton diffusion,reduces recombination losses,and enhances light capture capability.This approach not only offers a solution to achieving high-efficiency devices but also demonstrates the potential for commercial applications of OSCs. 展开更多
关键词 Organic solar cells Additive-assisted layer-by-layer processing Three-dimensional fibril morphology Bulk p-i-n structure Optical management
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Yolk–Shell CoNi@N‑Doped Carbon‑CoNi@CNTs for Enhanced Microwave Absorption,Photothermal,Anti‑Corrosion,and Antimicrobial Properties
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作者 Qiqin Liang Mukun He +6 位作者 Beibei Zhan Hua Guo Xiaosi Qi Yunpeng Qu Yali Zhang Wei Zhong Junwei Gu 《Nano-Micro Letters》 2025年第7期305-322,共18页
The previous studies mainly focused on improving microwave absorbing(MA)performances of MA materials.Even so,these designed MA materials were very difficult to be employed in complex and changing environments owing to... The previous studies mainly focused on improving microwave absorbing(MA)performances of MA materials.Even so,these designed MA materials were very difficult to be employed in complex and changing environments owing to their single-functionalities.Herein,a combined Prussian blue analogues derived and catalytical chemical vapor deposition strategy was proposed to produce hierarchical cubic sea urchin-like yolk–shell CoNi@Ndoped carbon(NC)-CoNi@carbon nanotubes(CNTs)mixed-dimensional multicomponent nanocomposites(MCNCs),which were composed of zerodimensional CoNi nanoparticles,three-dimensional NC nanocubes and onedimensional CNTs.Because of good impedance matching and attenuation characteristics,the designed CoNi@NC-CoNi@CNTs mixed-dimensional MCNCs exhibited excellent MA performances,which achieved a minimum reflection loss(RL_(min))of−71.70 dB at 2.78 mm and Radar Cross section value of−53.23 dB m^(2).More importantly,the acquired results demonstrated that CoNi@NC-CoNi@CNTs MCNCs presented excellent photothermal,antimicrobial and anti-corrosion properties owing to their hierarchical cubic sea urchin-like yolk–shell structure,highlighting their potential multifunctional applications.It could be seen that this finding not only presented a generalizable route to produce hierarchical cubic sea urchin-like yolk–shell magnetic NC-CNTs-based mixed-dimensional MCNCs,but also provided an effective strategy to develop multifunctional MCNCs and improve their environmental adaptabilities. 展开更多
关键词 Sea urchin Like yolk Shell structure CoNi@N Doped carbon CoNi@carbon nanotubes Mixed Dimensional nanocomposites Microwave absorption Photothermal and antimicrobial
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An Efficient and Flexible Bifunctional Dual-Band Electrochromic Device Integrating with Energy Storage
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作者 Zekun Huang Yutao Peng +7 位作者 Jing Zhao Shengliang Zhang Penglu Qi Xianlin Qu Fuqiang Yan Bing Ding Yimin Xuan Xiaogang Zhang 《Nano-Micro Letters》 2025年第4期419-434,共16页
Dual-band electrochromic devices capable of the spectral-selective modulation of visible(VIS)light and near-infrared(NIR)can notably reduce the energy consumption of buildings and improve the occupants’visual and the... Dual-band electrochromic devices capable of the spectral-selective modulation of visible(VIS)light and near-infrared(NIR)can notably reduce the energy consumption of buildings and improve the occupants’visual and thermal comfort.However,the low optical modulation and poor durability of these devices severely limit its practical applications.Herein,we demonstrate an efficient and flexible bifunctional dual-band electrochromic device which not only shows excellent spectral-selective electrochromic performance with a high optical modulation and a long cycle life,but also displays a high capacitance and a high energy recycling efficiency of 51.4%,integrating energy-saving with energy-storage.The nanowires structure and abundant oxygen-vacancies of oxygen-deficient tungsten oxide nanowires endows it high flexibility and a high optical modulation of 73.1%and 85.3%at 633 and 1200 nm respectively.The prototype device assembled can modulate the VIS light and NIR independently and effectively through three distinct modes with a long cycle life(3.3%capacity loss after 10,000 cycles)and a high energy-saving performance(8.8℃lower than the common glass).Furthermore,simulations also demonstrate that our device outperforms the commercial low-emissivity glass in terms of energy-saving in most climatic zones around the world.Such windows represent an intriguing potential technology to improve the building energy efficiency. 展开更多
关键词 Electrochromic Dual-band electrochromic devices Spectral-selective modulation FLEXIBLE Energy storage
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Technical roadmap of ultra-thin crystalline silicon-based bioelectronics
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作者 Mingyu Sang Kyubeen Kim +3 位作者 Doohyun J Lee Young Uk Cho Jung Woo Lee Ki Jun Yu 《International Journal of Extreme Manufacturing》 2025年第5期211-260,共50页
Ultra-thin crystalline silicon stands as a cornerstone material in the foundation of modern micro and nano electronics.Despite the proliferation of various materials including oxide-based,polymer-based,carbon-based,an... Ultra-thin crystalline silicon stands as a cornerstone material in the foundation of modern micro and nano electronics.Despite the proliferation of various materials including oxide-based,polymer-based,carbon-based,and two-dimensional(2D)materials,crystal silicon continues to maintain its stronghold,owing to its superior functionality,scalability,stability,reliability,and uniformity.Nonetheless,the inherent rigidity of the bulk silicon leads to incompatibility with soft tissues,hindering the utilization amid biomedical applications.Because of such issues,decades of research have enabled successful utilization of various techniques to precisely control the thickness and morphology of silicon layers at the scale of several nanometres.This review provides a comprehensive exploration on the features of ultra-thin single crystalline silicon as a semiconducting material,and its role especially among the frontier of advanced bioelectronics.Key processes that enable the transition of rigid silicon to flexible form factors are exhibited,in accordance with their chronological sequence.The inspected stages span both prior and subsequent to transferring the silicon membrane,categorized respectively as on-wafer manufacturing and rigid-to-soft integration.Extensive guidelines to unlock the full potential of flexible electronics are provided through ordered analysis of each manufacturing procedure,the latest findings of biomedical applications,along with practical perspectives for researchers and manufacturers. 展开更多
关键词 crystalline silicon OXIDATION DOPING transfer process flexible bioelectronics
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Investigation of Heterogeneous Ice Nucleation on the Micro-Cubic Structure Superhydrophobic Surface for Enhancing Icing-Delay Performance 被引量:1
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作者 Senyun Liu Qinglin Liu +5 位作者 Xian Yi Yizhou Shen Long Guo Wenqing Hou Haifeng Chen Zhen Wang 《Journal of Renewable Materials》 SCIE EI 2020年第12期1617-1631,共15页
The aim of this study is to explore the heterogeneous ice nucleation behavior based on controllable micro-cubic array structure surfaces from the statistic perspective.To this end,we firstly constructed a group of mic... The aim of this study is to explore the heterogeneous ice nucleation behavior based on controllable micro-cubic array structure surfaces from the statistic perspective.To this end,we firstly constructed a group of micro-cubic array structures on silicon substrates by a selective plasma etching technique.After grafting low-free-energy substance,the as-constructed micro-cubic array structure surfaces exhibited higher non-wettability with the water contact angle being up to 150°.On this basis,500 cycles of freezing and melting processes were accurately recorded to analyze the instantaneous ice nucleation behavior according to the statistical results of freezing temperature.As a consequence,the statistical freezing temperature of the sample with micro-spacing distance of 40μm is as low as−17.13°C.This microstructure configuration(conforming to Cassie-Baxter wetting regime)not only could entrap more air pockets,but also achieved lower solid-liquid contact area,resulting in lower ice nucleation rate(~2–3 orders of magnitude less than that on the flat substrate).Furthermore,the gradually increasing micro-spacing distance to 60μm would induce the transition from CassieBaxter to Wenzel wetting state,leading to higher freezing probability and ice nucleation rate.The complete understanding on microstructure configuration improving the ice nucleation will lay the foundation stone for the microstructure design of ice-repellent materials. 展开更多
关键词 Microstructure configuration SUPERHYDROPHOBIC ice nucleation antiicing/icephobic material
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Helicobacter pylori and gastric cancer: current status of the Austrian-Czech-German gastric cancer prevention trial (PRISMA-Study) 被引量:5
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作者 S.Miehlke C.Kirsch +12 位作者 B.Dragosics M.Gschwantler G.Oberhuber D.Antos P.Dite J.Lauter J.Labenz A.Leodolter P.Malfertheiner A.Neubauer G.Ehninger M.Stolte E.Bayerdorffer 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第2期243-247,共5页
AIM To test the hypothesis that Helicobacter pylori eradication alone can reduce the incidence of gastric cancer in a subgroup of individuals with an increased risk for this fatal disease.METHODS It is a prospective, ... AIM To test the hypothesis that Helicobacter pylori eradication alone can reduce the incidence of gastric cancer in a subgroup of individuals with an increased risk for this fatal disease.METHODS It is a prospective, randomized,double-blind, placebo-controlled multinational multicenter trial. Men between 55 and 65 years of age with a gastric cancer phenotype of Helicobacterpylori gastritis are randomized to receive a 7-day course of omeprazole 2 × 20 mg,clarithromycin 2 × 500 mg, and amoxicillin 2 ×lg for 7 days, or omeprazole2 × 20mg plusplacebo. Follow - up endoscopy is scheduled 3months after therapy, and thereafter in one-year intervals. Predefined study endpoints are gastric cancer, precancerous lesions (dysplasia, adenoma), other cancers, anddeath.RESULTS Since March 1998, 1524 target patients have been screened, 279 patients (18.3%) had a corpus-dominant type of H.pylori gastritis, and 167 of those were randomized (58.8%). In the active treatment group (n -- 86), H. pylori infection infection was cured in 88.9% of patients. Currently, thecumulative follow-up time is 3046 months (253.8patient-years, median follow-up 16 months). So far, none of the patients developed gastric cancer or any precancerous lesion. Three(1.8%) patients reached study endpoints other than gastric cancer.CONCLUSION Among men between 55 and 65years of age, the gastric cancer phenotype of H.pylori gastritis appears to be more common than expected. Further follow- up and continuing recruitment are necessary to fulfil the main aim of the study. 展开更多
关键词 HELICOBACTER pylori HELICOBACTER infections/complications HELICOBACTER infections/drug THERAPY STOMACH neoplasms /microbiology STOMACH neoplasms/drug THERAPY gastritis/microbiology gastritis/drug THERAPY
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An Isentropic Mass Circulation View on the Extreme Cold Events in the 2020/21 Winter 被引量:3
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作者 Yueyue YU Yafei LI +3 位作者 Rongcai REN Ming CAI Zhaoyong GUAN Wei HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第4期643-657,共15页
Three extreme cold events successively occurred across East Asia and North America in the 2020/21 winter.This study investigates the underlying mechanisms of these record-breaking persistent cold events from the isent... Three extreme cold events successively occurred across East Asia and North America in the 2020/21 winter.This study investigates the underlying mechanisms of these record-breaking persistent cold events from the isentropic mass circulation(IMC)perspective.Results show that the midlatitude cold surface temperature anomalies always co-occurred with the high-latitude warm anomalies,and this was closely related to the strengthening of the low-level equatorward cold air branch of the IMC,particularly along the climatological cold air routes over East Asia and North America.Specifically,the two cold surges over East Asia in early winter were results of intensification of cold air transport there,influenced by the Arctic sea ice loss in autumn.The weakened cold air transport over North America associated with warmer northeastern Pacific sea surface temperatures(SSTs)explained the concurrent anomalous warmth there.This enhanced a wavenumber-1 pattern and upward wave propagation,inducing a simultaneous and long-lasting stronger poleward warm air branch(WB)of the IMC in the stratosphere and hence a displacement-type Stratospheric Sudden Warming(SSW)event on 4 January.The WB-induced increase in the air mass transported into the polar stratosphere was followed by intensification of the equatorward cold branch,hence promoting the occurrence of two extreme cold events respectively over East Asia in the beginning of January and over North America in February.Results do not yield a robust direct linkage from La Niña to the SSW event,IMC changes,and cold events,though the extratropical warm SSTs are found to contribute to the February cold surge in North America. 展开更多
关键词 isentropic mass circulation extreme cold event Stratospheric Sudden Warming La Niña Arctic sea ice extratropical sea surface temperature
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An Engineered Heterostructured Trinity Enables Fire‑Safe,Thermally Conductive Polymer Nanocomposite Films with Low Dielectric Loss
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作者 Qiang Chen Jiabing Feng +9 位作者 Yijiao Xue Siqi Huo Toan Dinh Hang Xu Yongqian Shi Jiefeng Gao Long‑Cheng Tang Guobo Huang Weiwei Lei Pingan Song 《Nano-Micro Letters》 2025年第7期323-341,共19页
To adapt to the trend of increasing miniaturization and high integration of microelectronic equipments,there is a high demand for multifunctional thermally conductive(TC)polymeric films combining excellent flame retar... To adapt to the trend of increasing miniaturization and high integration of microelectronic equipments,there is a high demand for multifunctional thermally conductive(TC)polymeric films combining excellent flame retardancy and low dielectric constant(ε).To date,there have been few successes that achieve such a performance portfolio in polymer films due to their different and even mutually exclusive governing mechanisms.Herein,we propose a trinity strategy for creating a rationally engineered heterostructure nanoadditive(FG@CuP@ZTC)by in situ self-assembly immobilization of copper-phenyl phosphonate(CuP)and zinc-3,5-diamino-1,2,4-triazole complex(ZTC)onto the fluorinated graphene(FG)surface.Benefiting from the synergistic effects of FG,CuP,and ZTC and the bionic lay-by-lay(LBL)strategy,the as-fabricated waterborne polyurethane(WPU)nanocomposite film with 30 wt%FG@CuP@ZTC exhibits a 55.6%improvement in limiting oxygen index(LOI),66.0%and 40.5%reductions in peak heat release rate and total heat release,respectively,and 93.3%increase in tensile strength relative to pure WPU film due to the synergistic effects between FG,CuP,and ZTC.Moreover,the WPU nanocomposite film presents a high thermal conductivity(λ)of 12.7 W m^(−1) K^(−1) and a lowεof 2.92 at 106 Hz.This work provides a commercially viable rational design strategy to develop high-performance multifunctional polymer nanocomposite films,which hold great potential as advanced polymeric thermal dissipators for high-power-density microelectronics. 展开更多
关键词 Bionic strategy Fluorinated graphene Flame retardancy Thermal conductivity Dielectric constant
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Analysis method and experimental study of ice accumulation detection signal based on Lamb waves
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作者 Yanxin ZHANG Hongjian ZHANG +3 位作者 Xian YI Binrui WU Xianlei GUAN Jianjun XIONG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第8期388-403,共16页
A quantitative identification method for in-flight icing has the capability to significantly enhance the safety of aircraft operations.Ultrasonic guided waves have the unique advantage of detecting icing in a relative... A quantitative identification method for in-flight icing has the capability to significantly enhance the safety of aircraft operations.Ultrasonic guided waves have the unique advantage of detecting icing in a relatively large area,but quantitative identification of ice layers is a challenge.In this paper,a quantitative identification method of ice accumulation based on ultrasonic guided waves is proposed.Firstly,a simulation model for the wave dynamics of piezoelectric coupling in three dimensions is established to analyze the propagation characteristics of Lamb waves in a structure consisting of an aluminum plate and an ice layer.The wavelet transform method is utilized to extract the Time of Flight(ToF)or Time of Delay(ToD)of S_(0)/B_(1) mode waves,which serves as a characteristic parameter to precisely determine and assess the level of ice accumulation.Then,an experimental system is developed to evaluate the feasibility of Lamb waves-based icing real-time detection in the presence of spray conditions.Finally,a combination of the Hampel median filter and the moving average filter is developed to analyze ToF/ToD signals.Numerical simulation results reveal a positive correlation between geometric dimensions(length,width,thickness)of the ice layer and ToF/ToD of B1 mode waves,indicating their potential as indicators for quantifying ice accumulation.Experimental results of real-time icing detection indicate that ToF/ToD will reach greater peak values with the growth of the arbitrary-shaped ice layer until saturation to effectively predict the simulation results.This study lays a foundation for the practical application of quantitative icing detection via ultrasonic guided waves. 展开更多
关键词 ICE Ice accumulation Ultrasonic sensor Ultrasonic guided wave Lamb wave Wavelet transform
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Enhanced Multi-Object Dwarf Mongoose Algorithm for Optimization Stochastic Data Fusion Wireless Sensor Network Deployment
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作者 Shumin Li Qifang Luo Yongquan Zhou 《Computer Modeling in Engineering & Sciences》 2025年第2期1955-1994,共40页
Wireless sensor network deployment optimization is a classic NP-hard problem and a popular topic in academic research.However,the current research on wireless sensor network deployment problems uses overly simplistic ... Wireless sensor network deployment optimization is a classic NP-hard problem and a popular topic in academic research.However,the current research on wireless sensor network deployment problems uses overly simplistic models,and there is a significant gap between the research results and actual wireless sensor networks.Some scholars have now modeled data fusion networks to make them more suitable for practical applications.This paper will explore the deployment problem of a stochastic data fusion wireless sensor network(SDFWSN),a model that reflects the randomness of environmental monitoring and uses data fusion techniques widely used in actual sensor networks for information collection.The deployment problem of SDFWSN is modeled as a multi-objective optimization problem.The network life cycle,spatiotemporal coverage,detection rate,and false alarm rate of SDFWSN are used as optimization objectives to optimize the deployment of network nodes.This paper proposes an enhanced multi-objective mongoose optimization algorithm(EMODMOA)to solve the deployment problem of SDFWSN.First,to overcome the shortcomings of the DMOA algorithm,such as its low convergence and tendency to get stuck in a local optimum,an encircling and hunting strategy is introduced into the original algorithm to propose the EDMOA algorithm.The EDMOA algorithm is designed as the EMODMOA algorithm by selecting reference points using the K-Nearest Neighbor(KNN)algorithm.To verify the effectiveness of the proposed algorithm,the EMODMOA algorithm was tested at CEC 2020 and achieved good results.In the SDFWSN deployment problem,the algorithm was compared with the Non-dominated Sorting Genetic Algorithm II(NSGAII),Multiple Objective Particle Swarm Optimization(MOPSO),Multi-Objective Evolutionary Algorithm based on Decomposition(MOEA/D),and Multi-Objective Grey Wolf Optimizer(MOGWO).By comparing and analyzing the performance evaluation metrics and optimization results of the objective functions of the multi-objective algorithms,the algorithm outperforms the other algorithms in the SDFWSN deployment results.To better demonstrate the superiority of the algorithm,simulations of diverse test cases were also performed,and good results were obtained. 展开更多
关键词 Stochastic data fusion wireless sensor networks network deployment spatiotemporal coverage dwarf mongoose optimization algorithm multi-objective optimization
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Pollution and carbon reduction effects of the pilot policy on clean winter heating in Northern China:Evidence from the county level
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作者 Yan Chen Jiaqi Li +1 位作者 Yue Zhang Fan Yang 《Chinese Journal of Population,Resources and Environment》 2025年第1期85-95,共11页
Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implement... Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implemented the Pilot Policy on Clean Winter Heating in Northern China,aiming to achieve high central heating coverage and cleaner energy consumption.Studying the effects of this policy can help promote its implementation and serve as a reference for effective adjustment of the contents in the future.However,few studies have investigated this policy and its carbon reduction effects,and most focus on the provincial or city levels.Therefore,this paper considers the policy’s influence on air pollution and carbon emissions at the county level to provide a precise and comprehensive assessment of the policy effects.We use panel data from 1290 counties in 15 provinces in Northern China from 2014 to 2021,applying a multiperiod difference-in-differences model to quantify the impact of the policy on carbon emissions and air quality in the pilot area.We then conduct a series of tests to demonstrate the robustness of the results and analyze the mechanisms of the policy effects from two perspectives,namely,central heating and natural gas use,through a mediating effect model.Finally,we examine the heterogeneity of policy effects between counties based on geographic location and per capita income levels of rural residents through a moderating effect model.The results reveal that the policy significantly reduces air pollution and carbon emissions in the pilot area by increasing the central heating area and natural gas use.Compared with the central and western regions in the north and areas with low-income rural residents,the policy effects in the eastern regions in the north and areas with high-income rural residents are more pronounced. 展开更多
关键词 Pilot policy on clean winter heating Pollution and carbon reduction Multiperiod difference-in-differences model County-level analysis Northern China
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Differential Evolution with Improved Equilibrium Optimizer for Combined Heat and Power Economic Dispatch Problem
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作者 Yuanfei Wei Panpan Song +1 位作者 Qifang Luo Yongquan Zhou 《Computers, Materials & Continua》 2025年第10期1235-1265,共31页
The combined heat and power economic dispatch(CHPED)problem is a highly intricate energy dispatch challenge that aims to minimize fuel costs while adhering to various constraints.This paper presents a hybrid different... The combined heat and power economic dispatch(CHPED)problem is a highly intricate energy dispatch challenge that aims to minimize fuel costs while adhering to various constraints.This paper presents a hybrid differential evolution(DE)algorithm combined with an improved equilibrium optimizer(DE-IEO)specifically for the CHPED problem.The DE-IEO incorporates three enhancement strategies:a chaotic mechanism for initializing the population,an improved equilibrium pool strategy,and a quasi-opposite based learning mechanism.These strategies enhance the individual utilization capabilities of the equilibrium optimizer,while differential evolution boosts local exploitation and escape capabilities.The IEO enhances global search to enrich the solution space,and DE focuses on local exploitation for more accurate solutions.The effectiveness of DE-IEO is demonstrated through comparative analysis with other metaheuristic optimization algorithms,including PSO,DE,ABC,GWO,WOA,SCA,and equilibrium optimizer(EO).Additionally,improved algorithms such as the enhanced chaotic gray wolf optimization(ACGWO),improved particle swarm with adaptive strategy(MPSO),and enhanced SCA with elite and dynamic opposite learning(EDOLSCA)were tested on the CEC2017 benchmark suite and four CHPED systems with 24,84,96,and 192 units,respectively.The results indicate that the proposed DE-IEO algorithm achieves satisfactory solutions for both the CEC2017 test functions and real-world CHPED optimization problems,offering a viable approach to complex optimization challenges. 展开更多
关键词 CHPED DE EO large-scale system CEC2017 test suite metaheuristic optimization
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An Analytical Model for the Surface Electrical Field Distribution and Optimization of Bulk-Silicon Double RESURF Devices
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作者 李琦 李肇基 张波 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第7期1177-1182,共6页
A new 2D analytical model for the surface electrical field distribution and optimization of bulk-silicon double RESURF devices is presented. Based on the solution to the 2D Poisson's equation, the model gives the inf... A new 2D analytical model for the surface electrical field distribution and optimization of bulk-silicon double RESURF devices is presented. Based on the solution to the 2D Poisson's equation, the model gives the influence on the surface electrical field of the drain bias and structure parameters such as the doping concentration,the depth and the position of the p-top region, the thickness and the doping concentration of the drift region, and the substrate doping concentration. The dependence of breakdown voltage on the length and doping concentration of the drift region is also calculated. Further more,an effective way to gain the optimum high-voltage is also proposed. All analytical results are verified by simulation results obtained by MEDICI and previous experimental data,showing the validity of the model presented here. 展开更多
关键词 bulk-silicon double RESURF surface electrical field OPTIMIZATION
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Disabling portosystemic encephalopathy in a non-cirrhotic patient: successful endovascular treatment of a giant inferior mesenteric-caval shunt via the left internal iliac vein 被引量:3
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作者 Luca de Martinis Gloria Groppelli +5 位作者 Riccardo Corti Lorenzo Paolo Moramarco Pietro Quaretti Pasquale De Cata Mario Rotondi Luca Chiovato 《World Journal of Gastroenterology》 SCIE CAS 2017年第47期8426-8431,共6页
Hepatic encephalopathy is suspected in non-cirrhotic cases of encephalopathy because the symptoms are accompanied by hyperammonaemia. Some cases have been misdiagnosed as psychiatric diseases and consequently patients... Hepatic encephalopathy is suspected in non-cirrhotic cases of encephalopathy because the symptoms are accompanied by hyperammonaemia. Some cases have been misdiagnosed as psychiatric diseases and consequently patients hospitalized in psychiatric institutions or geriatric facilities. Therefore, the importance of accurate diagnosis of this disease should be strongly emphasized. A 68-year-old female patient presented to the Emergency Room with confusion, lethargy, nausea and vomiting. Examination disclosed normal vital signs. Neurological examination revealed a minimally responsive woman without apparent focal deficits and normal reflexes. She had no history of hematologic disorders or alcohol abuse. Her brain TC did not demonstrate any intracranial abnormalities and electroencephalography did not reveal any subclinical epileptiform discharges. Her ammonia level was > 400 mg/d L(reference range < 75 mg/d L) while hepatitis viral markers were negative. The patient was started on lactulose, rifaximin and low-protein diet.On the basis of the doppler ultrasound and abdomen computed tomography angiography findings, the decision was made to attempt portal venography which confirmed the presence of a giant portal-systemic venous shunt. Therefore, mechanic obliteration of shunt by interventional radiology was performed. As a consequence, mesenteric venous blood returned to hepatopetally flow into the liver, metabolic detoxification of ammonia increased and hepatic encephalopathy subsided. It is crucial that physicians immediately recognize the presence of non-cirrhotic encephalopathy, in view of the potential therapeutic resolution after accurate diagnosis and appropriate treatments. 展开更多
关键词 Non-cirrhotic patient Portosystemic shunt Hyperammonaemia Interventional radiology Mechanical embolization ENCEPHALOPATHY
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Research progress on construction strategy and technical evaluation of aircraft icing accretion protection system 被引量:9
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作者 Qiang HE Kangshuai LI +3 位作者 Zehua XU Jiwen WANG Xiaosen WANG Anling LI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第10期1-23,共23页
The impact of unstable supercooled water droplets suspended in the cloud on the solid will cause its surface to freeze,and the flight safety of the aircraft will be seriously affected when flying in this environment.A... The impact of unstable supercooled water droplets suspended in the cloud on the solid will cause its surface to freeze,and the flight safety of the aircraft will be seriously affected when flying in this environment.Aircraft icing protection system is an important device to reduce icing accidents and improve aircraft safety performance,which is of great significance to ensure flight safety.Based on the energy source,this paper proposes a general strategy for constructing an aircraft icing protection system,including Active Anti-icing and De-icing(AAD)system,Passive Antiicing and De-icing(PAD)system and Composite Anti-icing and De-icing(CAD)system.The principle,scope of application,advantages and disadvantages of aircraft anti-icing and de-icing technologies such as electric pulse de-icing,low-frequency piezoelectric de-icing,and hydrophobic material anti-icing are explored in detail,and the corresponding improvement measures are proposed.The future development of aircraft anti-icing and de-icing technology is prospected,and some new ideas are provided for the improvement of aircraft anti-icing and de-icing technology. 展开更多
关键词 Aircraft icing ANTI-ICING Construction strategy DE-ICING Evaluation method
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Numerical Study of Multi-Factor Coupling Effects on Energy Conversion Performance of Nanofluidic Reverse Electrodialysis
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作者 Hao Li Cunlu Zhao +4 位作者 Jinhui Zhou Jun Zhang Hui Wang Yanmei Jiao Yugang Zhao 《Frontiers in Heat and Mass Transfer》 2025年第2期507-528,共22页
Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extrac... Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extracting sustainable and clean energy fromthe salinity gradient energy.However,the scarcity of research investigating the intricate multi-factor coupling effects on the energy conversion performance,especially the trade-offs between ion selectivity and mass transfer in nanochannels,of NRED poses a great challenge to achieving breakthroughs in energy conversion processes.This numerical study innovatively investigates the multi-factor coupling effect of three critical operational factors,including the nanochannel configuration,the temperature field,and the concentration difference,on the energy conversion processes of NRED.In this work,a dimensionless amplitude parameter s is introduced to emulate the randomly varied wall configuration of nanochannels that inherently occur in practical applications,thereby enhancing the realism and applicability of our analysis.Numerical results reveal that the application of a temperature gradient,which is oriented in opposition to the concentration gradient,enhances the ion transportation and selectivity simultaneously,leading to an enhancement in both output power and energy conversion efficiency.Additionally,the increased fluctuation of the nanochannel wall from s=0 to s=0.08 improves ion selectivity yet raises ion transport resistance,resulting in an enhancement in output power and energy conversion efficiency but a slight reduction in current.Furthermore,with increasing the concentration ratio cH/cL from 10 to 1000,either within a fixed temperature field or at a constant dimensionless amplitude,the maximumpower consistently attains its optimal value at a concentration ratio of 100 but the cation transfer number experiences amonotonic decrease across this entire range of concentration ratios.Finally,uponmodifying the operational parameters fromthe baseline condition of s=0,c_(H)/c_(L)=10,andΔT=0 K to the targetedconditionof s=0.08,c_(H)/c_(L)=50,andΔT=25 K,there is a concerted improvement observed in the open-circuit potential,short-circuit current,andmaximumpower,with respective increments of 8.86%,204.97%,and 232.01%,but a reduction in cation transfer number with a notable decrease of 15.37%. 展开更多
关键词 Salinity gradient energy nanofluidic reverse electrodialysis energy conversion nanochannel configuration multi-factor coupling effect
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Investigating the Link between Ascaris Lumbricoides and Asthma in Human with Analysis of Fractal Fractional Caputo-Fabrizio of a Mathematical Model
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作者 Manal Adil Murad Shayma Adil Murad +2 位作者 Thabet Abdeljawad Aziz Khan D.K.Almutairi 《Computer Modeling in Engineering & Sciences》 2025年第6期3377-3409,共33页
Asthma is the most common allergic disorder and represents a significant global public health problem.Strong evidence suggests a link between ascariasis and asthma.This study aims primarily to determine the prevalence... Asthma is the most common allergic disorder and represents a significant global public health problem.Strong evidence suggests a link between ascariasis and asthma.This study aims primarily to determine the prevalence of Ascaris lumbricoides infection among various risk factors,to assess blood parameters,levels of immunoglobulin E(IgE)and interleukin-4(IL-4),and to explore the relationship between ascariasis and asthma in affected individuals.The secondary objective is to examine a fractal-fractional mathematical model that describes the four stages of the life cycle of Ascaris infection,specifically within the framework of the Caputo-Fabrizio derivative.A case-control study was conducted that involved 270 individuals with asthma and 130 healthy controls,all of whom attended general hospitals in Duhok City,Iraq.Pulmonary function tests were performed using a micromedical spirometer.The presence of Ascaris lumbricoides antibodies-Immunoglobulin M(IgM),Immunoglobulin G(IgG),and Immunoglobulin E(IgE)-was detected using ELISA.Blood parameters were analyzed using a Coulter counter.The overall infection rate was(42.5%),with the highest rates observed among asthmatic men(70.0%)and rural residents(51.4%).Higher infection rates were also recorded among low-income individuals(64.3%)and those with frequent contact with the soil(58.6%).In particular,infected individuals exhibited a significant decrease in red blood cell count and hemoglobin concentration,while a marked increase in white blood cell count was recorded.In addition,levels of Immunoglobulin E(IgE)and interleukin-4 were significantly higher in the infected group compared to the controls.Effective disease awareness strategies that incorporate health education and preventive measures are needed.Exposure to Ascaris has been associated with reduced lung function and an increased risk of asthma.More research is required to elucidate the precise mechanisms that link Ascaris infection with asthma.Furthermore,the existence and uniqueness of solutions for the proposed model are investigated using the Krasnosel’skii and Banach fixed-point theorems.The Ulam-Hyers and Ulam-Hyers-Rassias stability types are explained within the framework of nonlinear analysis inŁp-space.Finally,an application is presented,including tabulated results and figures generated using MATLAB to illustrate the validity of the theoretical findings. 展开更多
关键词 Ascaris lumbricoides ASTHMA fractal-fractional differential equation Caputo-Fabrizio derivative stability analysis
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