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Edge modes in finite-size systems with different edge terminals
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作者 Huiping Wang Li Ren +1 位作者 Xiuli Zhang Liguo Qin 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期381-387,共7页
We investigate the behavior of edge modes in the presence of different edge terminations and long-range(LR)hopping.Here,we mainly focus on such model crystals with two different types of structures(type I:“…-P-Q-P-Q... We investigate the behavior of edge modes in the presence of different edge terminations and long-range(LR)hopping.Here,we mainly focus on such model crystals with two different types of structures(type I:“…-P-Q-P-Q-…”and type II:“…=P-Q=P-Q=…”),where P and Q represent crystal lines(CLs),while the symbols“-”and“=”denote the distance between the nearest neighbor(NN)CLs.Based on the lattice model Hamiltonian with LR hopping,the existence of edge modes is determined analytically by using the transfer matrix method(TMM)when different edge terminals are taken into consideration.Our findings are consistent with the numerical results obtained by the exact diagonalization method.We also notice that edge modes can exhibit different behaviors under different edge terminals.Our result is helpful in solving novel edge modes in honeycomb crystalline graphene and transition metal dichalcogenides with different edge terminals. 展开更多
关键词 edge modes long-range hopping different edge terminals
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Improved STNModels and Heuristic Rules for Cooperative Scheduling in Automated Container Terminals
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作者 Hongyan Xia Jin Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1637-1661,共25页
Improving the cooperative scheduling efficiency of equipment is the key for automated container terminals to copewith the development trend of large-scale ships. In order to improve the solution efficiency of the exis... Improving the cooperative scheduling efficiency of equipment is the key for automated container terminals to copewith the development trend of large-scale ships. In order to improve the solution efficiency of the existing spacetimenetwork (STN) model for the cooperative scheduling problem of yard cranes (YCs) and automated guidedvehicles (AGVs) and extend its application scenarios, two improved STN models are proposed. The flow balanceconstraints in the original model are decomposed, and the trajectory constraints of YCs and AGVs are added toacquire the model STN_A. The coupling constraint in STN_A is updated, and buffer constraints are added toSTN_A so that themodel STN_B is built.As the size of the problem increases, the solution speed of CPLEX becomesthe bottleneck. So a heuristic method containing three groups of heuristic rules is designed to obtain a near-optimalsolution quickly. Experimental results showthat the computation time of STN_A is shortened by 49.47% on averageand the gap is reduced by 1.69% on average compared with the original model. The gap between the solution ofthe heuristic rules and the solution of CPLEX is less than 3.50%, and the solution time of the heuristic rules is onaverage 99.85% less than the solution time of CPLEX. Compared with STN_A, the computation time for solvingSTN_B increases by 58.93% on average. 展开更多
关键词 Automated container terminal BUFFER cooperative scheduling heuristic rules space-time network
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Polyethylene glycol fusion repair of severed rat sciatic nerves reestablishes axonal continuity and reorganizes sensory terminal fields in the spinal cord 被引量:1
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作者 Emily A.Hibbard Liwen Zhou +5 位作者 Cathy Z.Yang Karthik Venkudusamy Yessenia Montoya Alexa Olivarez George D.Bittner Dale R.Sengelaub 《Neural Regeneration Research》 SCIE CAS 2025年第7期2095-2107,共13页
Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically poor.We used a plasmalemmal fusogen,polyethylene g... Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically poor.We used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic nerves.We have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration,and PEG-fused animals exhibit rapid(within 2–6 weeks)and extensive locomotor recovery.Furthermore,our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific,i.e.,spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target muscles.In this study,we examined the consequences of PEG-fusion for sensory axons of the sciatic nerve.Young adult male and female rats(Sprague–Dawley)received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without(Negative Control)the application of PEG.Compound action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury site.The success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days postoperatively.At 2–42 days postoperatively,we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish peroxidase.PEG-fusion repair reestablished axonal continuity.Compared to unoperated animals,labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn,as well as inappropriate mediolateral and rostrocaudal areas.Unexpectedly,despite having intact peripheral nerves,similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repair.This central reorganization may contribute to the improved behavioral recovery seen after PEG-fusion repair,supporting the use of this novel repair methodology over currently available treatments. 展开更多
关键词 AXOTOMY dorsal horn peripheral nerve injury PLASTICITY polyethylene glycol(PEG) sciatic nerve sensory terminals wheat germ agglutinin horseradish peroxidase
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An Improved Bounded Conflict-Based Search for Multi-AGV Pathfinding in Automated Container Terminals
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作者 Xinci Zhou Jin Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2705-2727,共23页
As the number of automated guided vehicles(AGVs)within automated container terminals(ACT)continues to rise,conflicts have becomemore frequent.Addressing point and edge conflicts ofAGVs,amulti-AGVconflict-free path pla... As the number of automated guided vehicles(AGVs)within automated container terminals(ACT)continues to rise,conflicts have becomemore frequent.Addressing point and edge conflicts ofAGVs,amulti-AGVconflict-free path planning model has been formulated to minimize the total path length of AGVs between shore bridges and yards.For larger terminalmaps and complex environments,the grid method is employed to model AGVs’road networks.An improved bounded conflict-based search(IBCBS)algorithmtailored to ACT is proposed,leveraging the binary tree principle to resolve conflicts and employing focal search to expand the search range.Comparative experiments involving 60 AGVs indicate a reduction in computing time by 37.397%to 64.06%while maintaining the over cost within 1.019%.Numerical experiments validate the proposed algorithm’s efficacy in enhancing efficiency and ensuring solution quality. 展开更多
关键词 Automated terminals multi-AGV multi-agent path finding(MAPF) conflict based search(CBS) AGV path planning
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Security Risk Assessment in Container Terminals:Empirical Evidence from Greece
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作者 Constantinos Chlomoudis Petros Pallis Theodore Styliadis 《Journal of Traffic and Transportation Engineering》 2024年第5期214-223,共10页
The most prominent risk assessment techniques are founded on the values of measuring and controlling the frequency and the consequences of risks in order to assure an“acceptable level”of“safeness”mainly in the lin... The most prominent risk assessment techniques are founded on the values of measuring and controlling the frequency and the consequences of risks in order to assure an“acceptable level”of“safeness”mainly in the lines of environmental,health and hygiene and port product issues.This paper examines security risk assessment approaches within the emerging role of ports.This paper contributes to the current literature by considering the ports of Greece as a case in point and by measuring the degree of its security risk orientation based on certain valid risk factors drawn from the current literature.Moreover,it presents a security risk assessment methodology into the domain of port container terminals.Their potential for ports were quantitatively and qualitatively assessed by discussing issues of security approaches within the maritime industry,in order to facilitate improvement strategies.A two-dimension empirical study was conducted,in a time range of ten years(2010-2020)in order to provide evidence regarding security risk assessment in the port container terminal of Thessaloniki,in Greece.The findings of this study have significant strategic policy implications and shed more light on the role of security risks in the overall risk orientation of container terminals in practice.Finally,further research directions in security risk in ports are proposed. 展开更多
关键词 Greek ports risk assessment SECURITY container terminals empirical evidence
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Tailoring Nitrogen Terminals on MXene Enables Fast Charging and Stable Cycling Na-Ion Batteries at Low Temperature 被引量:6
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作者 Yang Xia Lanfang Que +6 位作者 Fuda Yu Liang Deng Zhenjin Liang Yunshan Jiang Meiyan Sun Lei Zhao Zhenbo Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第9期63-78,共16页
Sodium-ion batteries stand a chance of enabling fast charging ability and long lifespan while operating at low temperature(low-T).However,sluggish kinetics and aggravated dendrites present two major challenges for ano... Sodium-ion batteries stand a chance of enabling fast charging ability and long lifespan while operating at low temperature(low-T).However,sluggish kinetics and aggravated dendrites present two major challenges for anodes to achieve the goal at low-T.Herein,we propose an interlayer confined strategy for tailoring nitrogen terminals on Ti_(3)C_(2) MXene(Ti_(3)C_(2)-N_(funct)) to address these issues.The introduction of nitrogen terminals endows Ti_(3)C_(2)-N_(funct) with large interlayer space and charge redistribution,improved conductivity and sufficient adsorption sites for Na^(+),which improves the possibility of Ti_(3)C_(2) for accommodating more Na atoms,further enhancing the Na^(+) storage capability of Ti_(3)C_(2).As revealed,Ti_(3)C_(2)-N_(funct) not only possesses a lower Na-ion diffusion energy barrier and charge trans-fer activation energy,but also exhibits Na^(+)-solvent co-intercalation behavior to circumvent a high de-solvation energy barrier at low-T.Besides,the solid electrolyte interface dominated by inorganic com-pounds is more beneficial for the Na^(+)transfer at the electrode/electrolyte interface.Compared with of the unmodified sample,Ti_(3)C_(2)-Nfunct exhibits a twofold capacity(201 mAh g^(-1)),fast-charging ability(18 min at 80% capacity retention),and great superiority in cycle life(80.9%@5000 cycles)at -25℃.When coupling with Na_(3)V_(2)(PO_(4))_(2)F_(3) cathode,the Ti_(3)C_(2)-N_(funct)//NVPF exhibits high energy density and cycle stability at -25℃. 展开更多
关键词 Tailoring nitrogen terminals Na^(+)-solvent co-intercalation Interfacial kinetics Fast charging Low-temperature SIBs
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Discharge characteristics of different lightning air terminals under composite voltages 被引量:2
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作者 Chijie ZHUANG Zezhong WANG +5 位作者 Rong ZENG Lei LIU Te LI Min LI Yingzhe CUI Jinliang HE 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第5期1-4,共4页
Different types of lightning air terminals have been designed over the years.Concern regarding the effect of different types of air terminals,especially the early streamer emission(ESE)-type,remains controversial.This... Different types of lightning air terminals have been designed over the years.Concern regarding the effect of different types of air terminals,especially the early streamer emission(ESE)-type,remains controversial.This paper describes the discharge characteristics of different types of air terminals,two of which are quite similar to the ESE-type dynasphere,and concludes that the tested non-standard air terminals have discharge characteristics similar to those of Franklin rods and that their lightning protection performance should be similar. 展开更多
关键词 air terminal lightning protection discharge characteristics composite voltage LEADER
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Reliability Evaluation of All-User Terminals in LEO Satellite Communication Network Based on Modular Reduction 被引量:2
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作者 Yangyang Du Sifeng Liu +1 位作者 Zhigeng Fang Su Gao 《China Communications》 SCIE CSCD 2022年第2期235-246,共12页
LEO satellite communication network has a large number of satellites distributed in low orbits,which leads to multiple coverage of many areas on the ground.It is hard work to describe and evaluate the reliability of L... LEO satellite communication network has a large number of satellites distributed in low orbits,which leads to multiple coverage of many areas on the ground.It is hard work to describe and evaluate the reliability of LEO satellite communication network.To solve this problem,the reliability of all-user terminals in LEO satellite communication network is defined,and the corresponding reliability evaluation method is proposed in the paper.Due to the large scale of the interstellar network,a modular reduction algorithm using the modular network instead of the original network for state decomposition is proposed in this paper.Case study shows that the calculation time of the proposed method is equivalent to 6.28%of the original state space decomposition algorithm.On this basis,the reliability of LEO satellite communication network is further analyzed.It is found that the reliability of LEO satellite network was more sensitive to the reliability of Inter-Satellite link and the satisfaction of global coverage in the early stage,and it is more sensitive to the reliability of the satellite in the later stage.The satellite-ground link has a relatively constant impact on of LEO satellite network. 展开更多
关键词 reliability evaluation LEO satellite communication network modular approach full probability formula all-user terminals
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Providing Appropriate Solutions for Treatment and Sewage of Wastewaters in Cargo Terminals of Shorelines: An Emphasis on Terminal Bandar 被引量:1
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作者 Gholamreza Mansourri 《Open Journal of Ecology》 2016年第2期84-92,共9页
Low volume of produced wastewater and specific regional, environmental and economic condition in small communities determines the methods of treatment of sewage in such communities including shorelines of Bandar Abbas... Low volume of produced wastewater and specific regional, environmental and economic condition in small communities determines the methods of treatment of sewage in such communities including shorelines of Bandar Abbas, Bushehr, Imam Khomeini Harbor and Chabahar Harbor. Ineffective methods of treating and sewing wastewater in aforesaid terminals as well as limitations of methods of wastewater treatment such as high level of underground waters doubled the necessity of considering alternative methods. In this paper, investigation of current conditions was performed through field observations and data collection regarding wastewater production in terminals and determination of qualitative specifications using sampling and carrying out pH, TSS, COD, BOD and temperature tests from inlet to outlet of available sewage system of abovementioned terminals and comparison with environmental organization standards corresponding to wastewater sewage and it was found out that conditions of available systems of wastewater treatment are not suitable. In this regard, modifying solutions for the sake of improving performance of systems of wastewater treatment of terminals is presented in this research. Finally, for wastewater treatment system of Bandar Abbas terminal, if there is no limitation for allocating lands, it is recommended to use artificial canebrake system with underground flow. 展开更多
关键词 Cargo terminal WASTEWATER Wastewater Sewage
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A two-phase tabu search approach to scheduling optimization in container terminals 被引量:1
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作者 ZENG Qing-cheng YANG Zhong-zhen 《Journal of Marine Science and Application》 2007年第2期44-50,共7页
An optimization model for scheduling of quay cranes (QCs) and yard trailers was proposed to improve the overall efficiency of container terminals. To implement this model, a two-phase tabu search algorithm was designe... An optimization model for scheduling of quay cranes (QCs) and yard trailers was proposed to improve the overall efficiency of container terminals. To implement this model, a two-phase tabu search algorithm was designed. In the QCs scheduling phase of the algorithm, a search was performed to determine a good QC unloading operation order. For each QC unloading operation order generated during the QC's scheduling phase, another search was run to obtain a good yard trailer routing for the given QC's unloading order. Using this information, the time required for the operation was estimated, then the time of return to availability of the units was fed back to the QC scheduler. Numerical tests show that the two-phase Tabu Search algorithm searches the solution space efficiently, decreases the empty distance yard trailers must travel, decreases the number of trailers needed, and thereby reduces time and costs and improves the integration and reliability of container terminal operation systems. 展开更多
关键词 two-phase tabu search container terminal quay crane scheduling yard trailer routing
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A mutation in protein kinase C-gamma alters SNC neuron morphology and decreases synaptic vesicles in dopaminergic striatal terminals in the AS/AGU rat
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作者 Abdullah Glil Al-Kushi David Russell Anthony Philip Payne 《Journal of Biomedical Science and Engineering》 2013年第12期1129-1136,共8页
A spontaneous mutation in the Albino Swiss (AS) rat has been shown to be a single point mutation (agu) in the gene coding for the gamma isoform of protein kinase C (PKC-γ). The characteristics of the mutant include m... A spontaneous mutation in the Albino Swiss (AS) rat has been shown to be a single point mutation (agu) in the gene coding for the gamma isoform of protein kinase C (PKC-γ). The characteristics of the mutant include movement disorders, a failure to release dopamine in the striatum and elevations of molecules such as parkin and ubiquitin in the substantia nigra pars compacta (SNC). This present study examined SNC cell bodies and dopaminergic synaptic terminals within the caudate-putamen. Cell volume and nuclear volume were reduced in the AS/AGU mutant compared to the AS control, but the volume fractions of mitochondria and rough endoplasmic reticulum were significantly higher. No Lewy bodies were present in the mutant, although microglia were found adjacent to some SNC cells. Dopaminergic terminals were identified in the caudate-putamen by electron microscopy with low-glutaraldehyde fixation and immunohistochemistry for tyrosine hydroxylase using immuno-gold visualisation. AS/AGU mutant rats had less than half of the synaptic vesicles of AS controls;this was not only true of “readily-releasable” zones adjacent to the synaptic cleft but also “storage pool” zones. The findings support the hypothesis that the initial bar to dopamine availability in the striatum is the reduced release, with nigral cell death being a later phenomenon. 展开更多
关键词 PKC-Gamma Nigral DA NEURONS and terminals SNC NEURONS DOPAMINERGIC terminals
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Trigeminal primary afferent terminals containing substance P-like immunoreactivity in the paratrigeminal nucleus
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作者 张文斌 李继硕 李惠民 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第1期18-20,共3页
With the methods of transganglionic transport of horseradish peroxidase(HRP) combined with postembedding colloidal gold stain immunoelectron microscopy, the shape and synaptic relationship of the trigeminal primary af... With the methods of transganglionic transport of horseradish peroxidase(HRP) combined with postembedding colloidal gold stain immunoelectron microscopy, the shape and synaptic relationship of the trigeminal primary afferent terminals containing substance 展开更多
关键词 TRIGEMINAL nerve paratrigeminal NUCLEUS substance P-like IMMUNOREACTIVITY AFFERENT terminal electron microscopy
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Acute suppurative terminal cholangitis:Clinical characteristics of a new subtype of acute cholangitis 被引量:1
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作者 Rong-Tao Zhu Ye Li +5 位作者 Chi-Xian Zhang Wei-Jie Wang Ruo-Peng Liang Jian Li Kai Bai Yu-Ling Sun 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第3期293-299,共7页
Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well studied.To explore this subtype of acute cholangitis,we described our clinical experience with ASTC.Me... Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well studied.To explore this subtype of acute cholangitis,we described our clinical experience with ASTC.Methods:We performed a retrospective review of patients with ASTC admitted to our center from September 2014 to August 2020.We analyzed their clinical characteristics,including etiology,clinical manifestations,imaging features,treatment and prognosis.Results:A total of 32 ASTC patients were included in the analysis.The majority of the patients had a history of biliary operations,and clinical manifestations were occult and atypical.The positive rate of bacterial culture was 46.9%.All the patients had typical imaging features on computed tomography and magnetic resonance imaging.Treatment with effective antibiotics was provided as soon as diagnosis was established.After treatment,most patients had a good outcome.Elevated levels of total bilirubin,aspartate aminotransferase,procalcitonin and gamma-glutamyltransferase were the characteristics of critically ill patients and were associated with relatively poor prognosis.Conclusions:Our results demonstrated that ASTC should be recognized as a new subtype of acute cholangitis,and that earlier diagnosis and more personalized treatments are needed. 展开更多
关键词 Acute suppurative terminal cholangitis Acute cholangitis Gram-negative bacterial infections DIAGNOSIS Treatment
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Application of GNSS-PPP on Dynamic Deformation Monitoring of Offshore Platforms 被引量:1
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作者 YU Li-na XIONG Kuan +3 位作者 GAO Xi-feng LI Zhi FAN Li-long ZHANG Kai 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期352-361,共10页
The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe operation.Although Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has b... The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe operation.Although Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has been considered for this purpose,its monitoring accuracy is relatively low.Moreover,the influence of background noise on the dynamic monitoring accuracy of GNSS-PPP remains unclear.Hence,it is imperative to further validate the feasibility of GNSS-PPP for deformation monitoring of offshore platforms.To address these concerns,vibration table tests with different amplitudes and frequencies are conducted.The results demonstrate that GNSS-PPP can effectively monitor horizontal vibration displacement as low as±30 mm,which is consistent with GNSS-RTK.Furthermore,the spectral characteristic of background noise in GNSS-PPP is similar to that of GNSS-RTK(Real Time Kinematic).Building on this observation,an improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)has been proposed to de-noise the data and enhance the dynamic monitoring accuracy of GNSS-PPP.Field monitoring application research is also undertaken,successfully extracting and analyzing the dynamic deformation of an offshore platform structure under environmental excitation using GNSS-PPP monitoring in conjunction with improved CEEMDAN de-noising.By comparing the de-noised dynamic deformation trajectories of the offshore platform during different periods,it is observed that the platform exhibits reversible alternating vibration responses under environmental excitation,with more pronounced displacement deformation in the direction of load action.The research results confirm the feasibility and potential of GNSS-PPP for dynamic deformation monitoring of offshore platforms. 展开更多
关键词 GNSS-PPP offshore platform dynamic deformation monitoring improved CEEMDAN de-noising
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USING Hybrid Adaptive Techniques to Reduce Multipath Effects in S-PCN Mobile Terminals
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作者 Sunday E. Iwasokun Michael O. Kolawole 《Communications and Network》 2010年第4期246-250,共5页
Multipath signal processing is a promising technique for increasing the capacity of downlink frequency of satellite communication networks (S-PCN). The paper presents an approach to processing and reducing multipath s... Multipath signal processing is a promising technique for increasing the capacity of downlink frequency of satellite communication networks (S-PCN). The paper presents an approach to processing and reducing multipath signals received from S-PCN typified of mobile terminal users in clustered or mountainous environment. Use of hybrid linear adaptive antenna array technique and adaptive filtering technique provides improved performance by eliminating uncorrelated signal residing in antenna sidelobes. 展开更多
关键词 MULTIPATH Signal S-PCN HYBRID ADAPTIVE Technique ADAPTIVE Antenna Array Mobile terminAL
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High Isolation and Low Correlation Small Size Multi-Antenna for MIMO Mobile Terminals
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作者 Song Zhaohui Ding Zhiyong 《China Communications》 SCIE CSCD 2012年第5期100-107,共8页
A new method of forming a four-port multi-antenna by a two-unit patch antenna array is proposed to design a high isolation low correlation stroll size multi-antenna. Dual polarization is real-ized by the method of fee... A new method of forming a four-port multi-antenna by a two-unit patch antenna array is proposed to design a high isolation low correlation stroll size multi-antenna. Dual polarization is real-ized by the method of feeding in two ports. Defec-ted Ground Structure (DGS) is used to eliminate the coupling between the two antenna units. The test results show that the isolation between two ports reaches around 20dB, and that the antenna correlation coefficients is less than 0. 5, which meets the requirements of future mobile communi-cation systems and provides a solution to multi-antenna of MIMO terminals. 展开更多
关键词 MIMO mobile terminal antenna corre-lation DIVERSITY
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Machine learning for predicting the outcome of terminal ballistics events 被引量:1
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作者 Shannon Ryan Neeraj Mohan Sushma +4 位作者 Arun Kumar AV Julian Berk Tahrima Hashem Santu Rana Svetha Venkatesh 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期14-26,共13页
Machine learning(ML) is well suited for the prediction of high-complexity,high-dimensional problems such as those encountered in terminal ballistics.We evaluate the performance of four popular ML-based regression mode... Machine learning(ML) is well suited for the prediction of high-complexity,high-dimensional problems such as those encountered in terminal ballistics.We evaluate the performance of four popular ML-based regression models,extreme gradient boosting(XGBoost),artificial neural network(ANN),support vector regression(SVR),and Gaussian process regression(GP),on two common terminal ballistics’ problems:(a)predicting the V50ballistic limit of monolithic metallic armour impacted by small and medium calibre projectiles and fragments,and(b) predicting the depth to which a projectile will penetrate a target of semi-infinite thickness.To achieve this we utilise two datasets,each consisting of approximately 1000samples,collated from public release sources.We demonstrate that all four model types provide similarly excellent agreement when interpolating within the training data and diverge when extrapolating outside this range.Although extrapolation is not advisable for ML-based regression models,for applications such as lethality/survivability analysis,such capability is required.To circumvent this,we implement expert knowledge and physics-based models via enforced monotonicity,as a Gaussian prior mean,and through a modified loss function.The physics-informed models demonstrate improved performance over both classical physics-based models and the basic ML regression models,providing an ability to accurately fit experimental data when it is available and then revert to the physics-based model when not.The resulting models demonstrate high levels of predictive accuracy over a very wide range of projectile types,target materials and thicknesses,and impact conditions significantly more diverse than that achievable from any existing analytical approach.Compared with numerical analysis tools such as finite element solvers the ML models run orders of magnitude faster.We provide some general guidelines throughout for the development,application,and reporting of ML models in terminal ballistics problems. 展开更多
关键词 Machine learning Artificial intelligence Physics-informed machine learning terminal ballistics Armour
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Embedded System Implementation of Airborne Communication Terminals
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作者 Lei Wang Zhizhong Ding +2 位作者 Rui Huang Qian Li Hesheng Cheng 《Wireless Engineering and Technology》 2013年第3期139-144,共6页
Airborne communication terminal is a key unit in Ad hoc network of aircrafts. This paper mainly focuses on its implementation by embedded system, which is based on Samsung S3C2410 chip. System architecture, Linux tail... Airborne communication terminal is a key unit in Ad hoc network of aircrafts. This paper mainly focuses on its implementation by embedded system, which is based on Samsung S3C2410 chip. System architecture, Linux tailoring and touch-screen driver design are discussed in detail. Considering the requirements of stability and efficiency of the operating system, dynamic driver-loading method was employed firstly and only the necessary library files were transplanted to assist and test. The drivers finally were directly put into kernel configuration and then an integrated kernel was transplanted. Regarding to the problem of positioning issues on touch-screen, which is implemented in this system, an accurate positioning method is also presented. 展开更多
关键词 AIRBORNE Communication terminAL Ad HOC Network Embedded System Touch-Screen
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Measuring Conditions for the Determination of Lead in Iron-Matrix Samples Using Graphite Atomizers with/without a Platform in Graphite Furnace Atomic Absorption Spectrometry
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作者 Syun Morimoto Tetsuya Ashino Kazuaki Wagatsuma 《American Journal of Analytical Chemistry》 2011年第6期710-717,共8页
In graphite furnace atomic absorption spectrometry (GF-AAS), the atomization process of lead occurring in graphite atomizers with/without a platform plate was investigated when palladium was added to an iron-matrix sa... In graphite furnace atomic absorption spectrometry (GF-AAS), the atomization process of lead occurring in graphite atomizers with/without a platform plate was investigated when palladium was added to an iron-matrix sample solution containing trace amounts of lead. Absorption profiles of a lead line were meas- ured at various compositions of iron and palladium. Variations in the gas temperature were also estimated with the progress of atomization, by using a two-line method under the assumption of a Boltzmann distribu- tion. Each addition of iron and palladium increased the lead absorbance in both the atomizers, indicating that iron or palladium became an effective matrix modifier for the determination of lead. Especially, palladium played a significant role for controlling chemical species of lead at the charring stage in the platform-type atomizer, to change several chemical species to a single species and eventually to yield a dominant peak of the lead absorbance at the atomizing stage. Furthermore, the addition of palladium delayed the peak after the gas atmosphere in the atomizer was heated to a higher temperature. These phenomena would be because the temperature of the platform at the charring stage was elevated more slowly compared to that of the furnace wall, and also because a thermally-stable compound, such as a palladium-lead solid solution, was produced by their metallurgical reaction during heating of the charring stage. A platform-type atomizer with palladium as the matrix modifier is recommended for the determination of lead in GF-AAS. The optimum condition for this was obtained in a coexistence of 1.0 × 10–2 g/dm3 palladium, when the charring at 973 K and then the atomizing at 3073 K were conducted. 展开更多
关键词 GRAPHITE Furnace Atomic Absorption Spectrometry platform ATOMIZER Gas Temperature MATRIX MODIFIER LEAD Iron Palladium
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Studying the Effect of Urban Furniture on Satisfaction of Domestic Tourists in Isfahan Bus Terminals
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作者 Zahra Nadim Mehri Azani 《Open Journal of Geology》 2016年第9期1032-1044,共13页
Terminals and stations as one of the most important parts of transportation systems and also as the arteries of the country’s economy life undertake significant role in adjustment and regulation of the traffic pulse ... Terminals and stations as one of the most important parts of transportation systems and also as the arteries of the country’s economy life undertake significant role in adjustment and regulation of the traffic pulse of cities and roads. Urban furniture is one of the components considered in urban designing and as a part of the whole city, it defines the urban identity and structure. In today’s world, the importance of designing the urban equipment and furniture is to an extent that even active architects in the field of industrial designing are invited for designing and performing the urban furniture and equipment. Urban designing is a thing beyond making some flower box in squares and determining bus and taxi stations. Evidently, what gives identity to the city or according to the saying of “Sansovini”, what has tranquility for the city’s residents and creates attraction for foreigner tourists, not only include the mass buildings and streets traffic, but also include landscape, parks and furniture of the city. Standard designing of bus terminals like other urban furniture influences on urban face and it can have significant role in satisfaction of domestic tourists and increase and propagation of using of terminals. In this research, it has been attempted that the effect of furniture in the terminals of Isfahan city on domestic tourists should be studied that for this purpose, descriptive-analytic method has been used and data have been collected through field and library studies and secondary sources by using of SWOT model. 展开更多
关键词 Urban Furniture Domestic Tourism Bus terminal
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