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ISTIRDA:An Efficient Data Availability Sampling Scheme for Lightweight Nodes in Blockchain
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作者 Jiaxi Wang Wenbo Sun +3 位作者 Ziyuan Zhou Shihua Wu Jiang Xu Shan Ji 《Computers, Materials & Continua》 2026年第4期685-700,共16页
Lightweight nodes are crucial for blockchain scalability,but verifying the availability of complete block data puts significant strain on bandwidth and latency.Existing data availability sampling(DAS)schemes either re... Lightweight nodes are crucial for blockchain scalability,but verifying the availability of complete block data puts significant strain on bandwidth and latency.Existing data availability sampling(DAS)schemes either require trusted setups or suffer from high communication overhead and low verification efficiency.This paper presents ISTIRDA,a DAS scheme that lets light clients certify availability by sampling small random codeword symbols.Built on ISTIR,an improved Reed–Solomon interactive oracle proof of proximity,ISTIRDA combines adaptive folding with dynamic code rate adjustment to preserve soundness while lowering communication.This paper formalizes opening consistency and prove security with bounded error in the random oracle model,giving polylogarithmic verifier queries and no trusted setup.In a prototype compared with FRIDA under equal soundness,ISTIRDA reduces communication by 40.65%to 80%.For data larger than 16 MB,ISTIRDA verifies faster and the advantage widens;at 128 MB,proofs are about 60%smaller and verification time is roughly 25%shorter,while prover overhead remains modest.In peer-to-peer emulation under injected latency and loss,ISTIRDA reaches confidence more quickly and is less sensitive to packet loss and load.These results indicate that ISTIRDA is a scalable and provably secure DAS scheme suitable for high-throughput,large-block public blockchains,substantially easing bandwidth and latency pressure on lightweight nodes. 展开更多
关键词 Blockchain scalability data availability sampling lightweight nodes
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Prior-year climate and fuel availability shape fire occurrence in the semi-arid woody lands of Argentina
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作者 Laura B RODRÍGUEZ Silvia S TORRES-ROBLES Néstor I GASPARRI 《Journal of Arid Land》 2026年第2期202-215,共14页
Fire is a fundamental ecological driver shaping natural vegetation patterns.In the semi-arid southern Espinal-Monte ecotone of Argentina,the spatiotemporal patterns of fire occurrence related to and modulated by clima... Fire is a fundamental ecological driver shaping natural vegetation patterns.In the semi-arid southern Espinal-Monte ecotone of Argentina,the spatiotemporal patterns of fire occurrence related to and modulated by climatic gradients and antecedent conditions are not well researched.This study examined fire occurrence in the semi-arid southern Espinal-Monte ecotone(southeastern La Pampa,northeastern Río Negro,and southwestern Buenos Aires with an area of 68×103 km2)of Argentina,a key environmental transition zone with pronounced climatic and vegetation gradients.The objective was to identify the spatiotemporal patterns of fire occurrence and their relationship with climatic variables.Thermal anomaly(TA)data from the MODIS(Moderate Resolution Imaging Spectrometer;MOD14)sensor(November 2000–March 2020)with confidence levels>65.0%were analyzed.Climatic variables(rainfall isohyets and aridity indices)were obtained from the WorldClim datasets,and annual meteorological conditions(rainfall and potential evapotranspiration)were calculated using the climatic research unit(CRU)database.Monthly data and moving averages of rainfall and aridity indices from distinct periods(two and three years preceding fire events)were integrated.Spatial analysis was conducted using kernel density estimation on a 10 km×10 km grid to correlate TA with climatic gradients,while linear regression examined relationships between summer TA and meteorological variables over different periods.Results showed that the highest fire occurrence was recorded in summer,with peaks in December and January.Spatially,55.0%of TA occurred in areas with annual rainfall of 300–400 mm,and 64.5%in areas with an aridity index of 0.3–0.4,forming an arc-like distribution in the center of the ecotone.The highest TA densities were observed in southeastern La Pampa and northeastern Río Negro,decreasing toward southwestern Buenos Aires.Significant correlations(R2>0.700)were found among TA accumulation,aridity index values,and cumulative rainfall from previous two and three years,at both vegetation unit and provincial levels.Summer was the critical season for fire occurrence,with spatial distribution primarily determined by the interaction between climatic conditions and woody biomass availability.The lower fire incidence in southwestern Buenos Aires was linked to sparse woody vegetation and agricultural expansion,which reduced fuel load.These findings reinforce that fuel availability,modulated by climatic conditions from previous years,is a key limiting factor for fire dynamics in this area,and that human activities such as agriculture and grazing alter fire regimes by affecting fuel structure and continuity. 展开更多
关键词 fire occurrence Espinal-Monte ecotone climatic variables spatiotemporal patterns fuel availability
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Taxon-specific microbial responses to land-use and landscape heterogeneity are modulated by soil nutrient availability
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作者 Hanghang Zhang Zhi Wen +2 位作者 Zhiyong Wang Ruonan Li Hua Zheng 《Ecological Frontiers》 2026年第1期254-262,共9页
Land-use change and associated landscape pattern modifications are key drivers of biodiversity dynamics.However,the influence of landscape heterogeneity on soil microbial diversity remains poorly understood.This study... Land-use change and associated landscape pattern modifications are key drivers of biodiversity dynamics.However,the influence of landscape heterogeneity on soil microbial diversity remains poorly understood.This study analyzed soil microbial communities(bacteria and fungi)and soil properties(organic carbon,pH,available potassium,nitrogen,and phosphorus)across 74 sites in Hainan,China,covering six land-use types(rubber,areca,banana,farmland,longan,and mango).We evaluated the effects of both landscape composition(habitat coverage and patch richness)and configuration heterogeneity(patch density and largest patch index)on soil microbial community structure and diversity.Results show that land-use types and landscape patterns weakly affect microbial composition but strongly shape diversity in a taxon-specific way.Bacterial Chao1 richness and fungal Shannon diversity varied significantly among land-use types,mainly due to soil available phosphorus.Rubber coverage positively correlated with bacterial and fungal diversity,while the largest patch index negatively affected only fungal diversity.Available phosphorus reduced this negative effect.This study demonstrates that land-use change and landscape heterogeneity differentially influence soil microbial composition and diversity,with available phosphorus emerging as a key determinant.Our findings highlight the need for careful landscape planning and soil nutrient management to preserve soil microbial diversity. 展开更多
关键词 Land-use change Landscape pattern Soil microbial diversity Available phosphorus
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Unit Commitment with Concentrating Solar Power Considering Operational Risk and Frequency Dynamic Constraints
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作者 Yuchen Fang Ershun Du +3 位作者 Haiyang Jiang Fei Liu Xu Tian Ning Zhang 《CSEE Journal of Power and Energy Systems》 2026年第1期230-243,共14页
The large-scale integration of power electronic interface-based renewable energy with intermittency and uncertainty poses severe challenges for power system secure operation,especially frequency security.Determining t... The large-scale integration of power electronic interface-based renewable energy with intermittency and uncertainty poses severe challenges for power system secure operation,especially frequency security.Determining the system frequency regulation ability under contingency is an open problem.To bridge this gap,a unit commitment(UC)to concentrate solar power considering operational risk and frequency dynamic constraints(RFUC-CSP)is proposed in this paper.A concentrating solar power(CSP)plant with renewable energy characteristics and synchronous units is employed to improve renewable energy utilization and provide frequency support.Firstly,an analytical operational risk model is established to quantify the operational risk under renewable energy integration.Then,the frequency dynamic response characteristic of the system is considered to construct frequency security constraints.A novel RFUC-CSP framework is formulated by incorporating operational risk and frequency security constraints into the UC model,which can allocate operational flexibility of power systems by optimizing the admissible uncertainty level to reduce operational risk.The effectiveness of the proposed RFUC-CSP model is demonstrated by case studies on the modified IEEE 30-bus and IEEE RTS-79 system,and the cost-effectiveness of the CSP plant is quantified. 展开更多
关键词 Concentrating solar power frequency dynamics operational risk power system inertia unit commitment
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Deep reinforcement learning-based adaptive collision avoidance method for UAV in joint operational airspace
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作者 Yan Shen Xuejun Zhang +1 位作者 Yan Li Weidong Zhang 《Defence Technology(防务技术)》 2026年第2期142-159,共18页
As joint operations have become a key trend in modern military development,unmanned aerial vehicles(UAVs)play an increasingly important role in enhancing the intelligence and responsiveness of combat systems.However,t... As joint operations have become a key trend in modern military development,unmanned aerial vehicles(UAVs)play an increasingly important role in enhancing the intelligence and responsiveness of combat systems.However,the heterogeneity of aircraft,partial observability,and dynamic uncertainty in operational airspace pose significant challenges to autonomous collision avoidance using traditional methods.To address these issues,this paper proposes an adaptive collision avoidance approach for UAVs based on deep reinforcement learning.First,a unified uncertainty model incorporating dynamic wind fields is constructed to capture the complexity of joint operational environments.Then,to effectively handle the heterogeneity between manned and unmanned aircraft and the limitations of dynamic observations,a sector-based partial observation mechanism is designed.A Dynamic Threat Prioritization Assessment algorithm is also proposed to evaluate potential collision threats from multiple dimensions,including time to closest approach,minimum separation distance,and aircraft type.Furthermore,a Hierarchical Prioritized Experience Replay(HPER)mechanism is introduced,which classifies experience samples into high,medium,and low priority levels to preferentially sample critical experiences,thereby improving learning efficiency and accelerating policy convergence.Simulation results show that the proposed HPER-D3QN algorithm outperforms existing methods in terms of learning speed,environmental adaptability,and robustness,significantly enhancing collision avoidance performance and convergence rate.Finally,transfer experiments on a high-fidelity battlefield airspace simulation platform validate the proposed method's deployment potential and practical applicability in complex,real-world joint operational scenarios. 展开更多
关键词 Unmanned aerial vehicle Collision avoidance Deep reinforcement learning Joint operational airspace Hierarchical prioritized experience replay
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Female-female Amplexus and Extremely Female-skewed Operational Sex Ratio in the Toad Duttaphrynus cyphosus During Breeding Seasons
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作者 Hongzhou CHEN Jinyu XIA +2 位作者 Tuo LI Buddhi DAYANANDA Wei CHEN 《Asian Herpetological Research》 2026年第1期45-46,共2页
Dear Editor,Amplexus,a reproductive behavior in which the male clasps the female dorsally,is a characteristic of amphibians(Wells,2007).Most species exhibit either inguinal or axillary amplexus,although some reproduce... Dear Editor,Amplexus,a reproductive behavior in which the male clasps the female dorsally,is a characteristic of amphibians(Wells,2007).Most species exhibit either inguinal or axillary amplexus,although some reproduce without it(Wells,2007).While male-female amplexus is predominant,other forms such as male-male and multiple-male amplexus have also been documented(Soni et al.,2025).Release calls are typically produced by amplexed males to signal mating mismatches and mitigate the costs of inappropriate clasping(Kelehear and Shine,2019).Female-female amplexus,however,is rare and considered maladaptive,as it does not lead to fertilization(Chuang et al.,2019). 展开更多
关键词 amplexed males female female amplexus reproductive behavior signal mating mismatches inguinal axillary amplexusalthough operational sex ratio breeding season Duttaphrynus cyphosus
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Functional evidential reasoning model(FERM)-A new systematic approach for exploring hazardous chemical operational accidents under uncertainty 被引量:1
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作者 Qianlin Wang Jiaqi Han +6 位作者 Lei Cheng Feng Wang Yiming Chen Zhan Dou Bing Zhang Feng Chen Guoan Yang 《Chinese Journal of Chemical Engineering》 2025年第5期255-269,共15页
This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal... This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal factors and their performance changes in hazardous chemical operational accidents, along with determining the functional failure link relationships. Subsequently, FERM was employed to elucidate both qualitative and quantitative operational accident information within a unified framework, which could be regarded as the input of information fusion to obtain the fuzzy belief distribution of each cause factor. Finally, the derived risk values of the causal factors were ranked while constructing multi-level accident causation chains to unveil the weak links in system functionality and the primary roots of operational accidents. Using the specific case of the “1·15” major explosion and fire accident at Liaoning Panjin Haoye Chemical Co., Ltd., seven causal factors and their corresponding performance changes were identified. Additionally, five accident causation chains were uncovered based on the fuzzy joint distribution of the functional assessment level(FAL) and reliability distribution(RD),revealing an overall increase in risk along the accident evolution path. The research findings demonstrated that FERM enabled the effective characterization, rational quantification and accurate analysis of the inherent uncertainties in hazardous chemical operational accident risks from a systemic perspective. 展开更多
关键词 Functional evidential reasoning model (FERM) Accident causation analysis operational accidents Hazardous chemical UNCERTAINTY
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Multiscale track-seabed dynamic interaction during deep-sea seabed mining across operational modes 被引量:1
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作者 Bin Zhu Xianhao Xiu +5 位作者 Ying Lai Yunmin Chen Viroon Kamchoom Anthony Gunawan Ruishi Zhang Shusen Xiong 《International Journal of Mining Science and Technology》 2025年第11期2055-2071,共17页
Deep-sea mining has emerged as a critical solution to address global resource shortages;however,the mechanical interaction between tracked mining vehicles(TMVs)and soft seabed sediments presents fundamental engineerin... Deep-sea mining has emerged as a critical solution to address global resource shortages;however,the mechanical interaction between tracked mining vehicles(TMVs)and soft seabed sediments presents fundamental engineering challenges.This study establishes a multiscale modelling framework coupling the discrete element method(DEM)with multi-body dynamics(MBD)to investigate track-seabed dynamic interactions across three operational modes:flat terrain,slope climbing,and ditch surmounting.The simulation framework,validated against laboratory experiments,systematically evaluates the influence of grouser geometry(involute,triangular,and pin-type)and traveling speed(0.2–1.0 m/s)on traction performance,slip rate,and ground pressure distribution.Results reveal rate-dependent traction mechanisms governed by soil microstructural responses:higher speeds enhance peak traction but exacerbate slip instability on complex terrain.Critical operational thresholds are established—0.7 m/s for flat terrain,≤0.5 m/s for slopes and ditches—with distinct grouser optimization strategies:involute grousers achieve 35%–40%slip reduction on slopes through progressive soil engagement,while triangular grousers provide optimal impact resistance during ditch crossing with 30%–35%performance improvement.These findings provide quantitative design criteria and operational guidelines for optimizing TMV structural parameters and control strategies,offering a robust theoretical foundation for enhancing the performance,safety,and reliability of deep-sea mining equipment in complex submarine environments. 展开更多
关键词 Deep-sea mining Tracked mining vehicle Track-soil interaction DEM-MBD coupling Soft seabed sediment operational performance
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Innovative strategies to increase cardiac donor availability
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作者 Benjamin Alexander Herra Javed +3 位作者 Anshaal Furrukh Krittika Joshi Louis Steen Taufiek Konrad Rajab 《World Journal of Transplantation》 2025年第3期62-69,共8页
Heart transplantation is a life-saving procedure for many people throughout the world.Data shows that in 2024,there was an increase in the volume of adult heart transplantation in the United States even as there was a... Heart transplantation is a life-saving procedure for many people throughout the world.Data shows that in 2024,there was an increase in the volume of adult heart transplantation in the United States even as there was a decrease in the volume of pediatric heart transplantation to the lowest volume in a decade.Organ availability remains a major limiting factor affecting transplant volume.This mandates that innovation must take place to increase the supply of donor organs.While some strategies such as donation after cardiac death,hepatitis C virus+transplantation,and ABO-incompatible transplantation have increased the pool for donation,it still falls short of meeting the demand.Other proposed strategies include splitting the donor heart to provide multiple partial heart transplants,domino partial heart transplantation,changes in legislation including opt-out legislation,and xenotransplantation.Further evolution and refinement of these strategies will make a meaningful impact on patients awaiting life-saving heart transplants. 展开更多
关键词 Heart transplantation Partial heart translation Domino transplantation Organ availability Valvular transplantation
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Improving kinetic modelling of magnesium hydrogenation by including interfacial polarisation and interstitial hydrogen clustering behaviour within the site availability model
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作者 Marcus J.Adams Alastair Stuart +1 位作者 Gavin S.Walker David M.Grant 《Journal of Magnesium and Alloys》 2025年第5期2009-2022,共14页
Recent work analysing magnesium hydrogenation using Reflecting Electron Energy Loss Spectroscopy(REELS)and Density Function Theory(DFT)has indicated interfacial polarisation and interstitial hydrogen clustering influe... Recent work analysing magnesium hydrogenation using Reflecting Electron Energy Loss Spectroscopy(REELS)and Density Function Theory(DFT)has indicated interfacial polarisation and interstitial hydrogen clustering influence the reaction rate.The site availability model has been modified to include interstitial hydrogen clustering within the site availability factor and interface polarisation using interface treatment.The new model,SAM-CV-S,has demonstrated improved modelling of magnesium hydrogenation across wide operating conditions,such as temperatures from 330 to 400℃and pressures up to 40 bar.This wide applicability makes it a robust model that can be used to simulate bed performance in solid-state hydrogen stores.Thus,the site availability factor successfully combines interstitial hydrogen clustering with thermal resistance effects,which are known to strongly influence metal hydride reactor designs at scale.The next phase of the model is to incorporate a predictive hydrogen capacity method into the model. 展开更多
关键词 Magnesium hydrogenation kinetics Site availability factor Interstitial hydrogen clustering Interfacial polarisation
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Effects of nitrosamine impurities on the availability of Reference Listed drugs in China
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作者 Dongsheng Yang Jianzhao Niu +2 位作者 Yufei Feng Nian Liu Lingyun Ma 《Journal of Chinese Pharmaceutical Sciences》 2025年第1期75-81,共7页
The Reference Listed drug(RLD)plays a critical role in the development and research of generic medicinal products,serving as the comparator product used in the marketing authorization application of new generic medici... The Reference Listed drug(RLD)plays a critical role in the development and research of generic medicinal products,serving as the comparator product used in the marketing authorization application of new generic medicinal product and re-evaluation of generic medicinal product.In China,RLDs are sourced from various origins,but their quality and market availability can be constrained by multiple factors,including emergent issues such as nitrosamine impurities.Five classes of medicinal products have been reported to be at risk for containing nitrosamine impurities:sartan-based medicines,metformin-containing products,ranitidine medicines,rifampicin medicines,and Champix.This paper explores the control strategies implemented by drug regulatory agencies in the United States and the European Union to manage nitrosamine impurities and assesses their impact on the market availability and quality of RLDs in China.The aim is to offer valuable insights for generic drug manufacturers and regulatory bodies both domestically and internationally. 展开更多
关键词 Reference Listed drugs Nitrosamine impurities Food and Drug Administration European Medicines Agency availability
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Pathfinder:a tool for operational planning of forest regeneration on clearcuts
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作者 Linnea J.Hansson Anders Rowell +5 位作者 Mikael Rönnqvist Patrik Flisberg Fredrik Johansson Rasmus Sörensen Morgan Rossander Petrus Jönsson 《Journal of Forestry Research》 2025年第4期41-54,共14页
Effective forest regeneration is essential for sustainable forestry practices.In Sweden,mechanical site preparation and manual planting is the dominating method,but sourcing labour for the physically demanding work is... Effective forest regeneration is essential for sustainable forestry practices.In Sweden,mechanical site preparation and manual planting is the dominating method,but sourcing labour for the physically demanding work is difficult.An autonomous scarifying and planting system(Autoplant)could meet the requirements of the forest industry and,for this,a tool for regeneration planning and routing is needed.The tool,Pathfinder,plans the regeneration and routes based on the harvested production(hpr)files,soil moisture and parent material maps,no-go areas(for culture or nature conservation),digital elevation models(DEM),and machine data(e.g.,working width,critical slope,time taken for different turn angles).The overall planting solution is either a set of capacity constrained routes or a continuous route and could be used for any planting machine as well as for traditional scarifiers as disc trenchers or mounders pulled by forwarders.Pathfinder was tested on eleven regeneration areas throughout Sweden,both with continuous routes and routes based on a carrying capacity of 1500 seedlings.The net operation area,species and seedling density suggestions were deemed relevant by expert judgement in the field.The routes provided by Pathfinder were compared with solutions given by two experienced drivers and a third solution based on the actual soil scarification at the site.Total driving distance did not differ significantly between the suggestions,but Pathfinder included less side-slope driving on steep slopes(≥27%or 15°)and medium slopes(15–27%).The chosen threshold value for steep slopes(where side-slope driving should be avoided)affects the routing,and a lower threshold means more turning and longer driving distance.Pathfinder is not only a tool for routing of planting machines,but also helps in planning of traditional regeneration by providing a more correct net area and tree species suggestions based on the growth of the previous stand.It also diminishes the risk of severe soil disturbance by excluding the wettest area in the planning. 展开更多
关键词 ROUTING Site preparation PLANTING operational planning OPTIMIZATION
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Optimization strategies for operational parameters of Rydberg atom-based amplitude modulation receiver
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作者 Yuhao Wu Dongping Xiao +1 位作者 Huaiqing Zhang Sheng Yan 《Chinese Physics B》 2025年第1期280-287,共8页
The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches... The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches between the parameters of the received amplitude modulation(AM) signals and the system's linear workspace and demodulation operating points can cause severe distortion in the demodulated signals. To address this, the article proposes a method for determining the operational parameters based on the mean square error(MSE) and total harmonic distortion(THD) assessments and presents strategies for optimizing the system's operational parameters focusing on linear response characteristics(LRC) and linear dynamic range(LDR). Specifically, we employ a method that minimizes the MSE to define the system's linear workspace, thereby ensuring the system has a good LRC while maximizing the LDR. To ensure that the signal always operates within the linear workspace, an appropriate carrier amplitude is set as the demodulation operating point. By calculating the THD at different operating points, the LRC performance within different regions of the linear workspace is evaluated, and corresponding optimization strategies based on the range of signal strengths are proposed. Moreover, to more accurately restore the baseband signal, we establish a mapping relationship between the carrier Rabi frequency and the transmitted power of the probe light, and optimize the slope of the linear demodulation function to reduce the MSE to less than 0.8×10^(-4). Finally, based on these methods for determining the operational parameters, we explore the effects of different laser Rabi frequencies on the system performance, and provide optimization recommendations. This research provides robust support for the design of high-performance Rydberg atom-based AM receivers. 展开更多
关键词 Rydberg atom-based receiver amplitude modulation(AM) operating parameters OPTIMIZATION
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Molecular transformation of heavy oil during slurry phase hydrocracking process:Influences of operational conditions
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作者 Jing-Man Lu Yuan-Feng Wang +6 位作者 Zhi-Yuan Zhou Jian-Xun Wu Ya-He Zhang Lin-Zhou Zhang Quan Shi Sheng-Bao He Chun-Ming Xu 《Petroleum Science》 2025年第2期884-893,共10页
The influences of reaction temperature,duration,pressure,and catalyst concentration on the molecular transformation of residual slurry phase hydrocracking process were investigated.The molecular composition of the het... The influences of reaction temperature,duration,pressure,and catalyst concentration on the molecular transformation of residual slurry phase hydrocracking process were investigated.The molecular composition of the heteroatom compounds in the residue feedstock and its upgrading products were characterized using high-resolution Orbitrap mass spectrometry coupled with multiple ionization methods.The simultaneous promotion of cracking and hydrogenation reactions was observed with increasing of the reaction temperature and time.Specifically,there was a significant increase in the cracking degree of alkyl side chain,while the removal of low-condensation sulfur compounds such as sulfides and benzothiophenes was enhanced.In particular,the cracking reactions were more significantly facilitated by high temperatures,while an appropriately extended reaction time can result in the complete elimination of the aforementioned sulfur compounds with a lower degree of condensation.Under conditions of low hydrogen pressure and catalyst concentration,the products still exhibit a high relative abundance of easily convertible compounds such as sulfoxides,indicating a significant deficiency in the effectiveness of hydrogenation.The hydrogen pressure exhibits an optimal value,beyond which further increments have no effect on the composition and performance of the liquid product but can increase the yield of the liquid product.At significantly high catalyst concentration,the effect of desulfurization and deoxidation slightly diminishes,while the aromatic saturation of highly condensed compounds was notably enhanced.This hydrogenation saturation effect cannot be attained through manipulation of other operational parameters,thereby potentially benefiting subsequent product processing and utilization.This present study demonstrates a profound comprehension of the molecular-level residue slurry phase hydrocracking process,offering not only specific guide for process design and optimization but also valuable fundamental data for constructing reaction models at the molecular level. 展开更多
关键词 Slurry phase hydrocracking Operating condition Orbitrap MS Molecular composition
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Continuity and integrity allocation over operational exposure time for ARAIM fault detection algorithm
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作者 Jingtian DU Hongxia WANG +2 位作者 Kun FANG Zhipeng WANG Yanbo ZHU 《Chinese Journal of Aeronautics》 2025年第11期329-345,共17页
The snapshot Fault Detection(FD)algorithm of Advanced Receiver Autonomous Integrity Monitoring(ARAIM)necessitates the allocation of continuity and integrity risk requirements from the operational exposure time level t... The snapshot Fault Detection(FD)algorithm of Advanced Receiver Autonomous Integrity Monitoring(ARAIM)necessitates the allocation of continuity and integrity risk requirements from the operational exposure time level to the single epoch level.Current studies primarily focus on finding a conservative Number of Effective Samples(NES)as a risk mapping factor.However,considering that the NES varies with the observation environment and the type of the fault mode,applying a fixed NES can constrain the performance of the algorithm.To address this issue,the continuity and integrity risks over the operational exposure time are analyzed and bounded based on all epochs within the exposure time.A more adaptable method for continuity and integrity budget allocation over the operational exposure time is presented,capable of monitoring the continuity and integrity risks over the recent operational exposure time in real time,and dynamically adjusting the allocation values based on the current observation environment.Simulation results demonstrate that,compared with the allocation method based on a fixed NES,ARAIM based on the proposed allocation method exhibits superior performance in terms of the availability.At an FD execution frequency equal to the required Time-To-Alert(TTA),the dual-constellation H-ARAIM provides 100%of the global coverage with 99.5%availability of the RNP 0.1 service,and the dual-constellation V-ARAIM provides 86.38%of the global coverage with 99.5%availability of the LPV-200 service. 展开更多
关键词 Air navigation Advanced Receiver Autonomous Integrity Monitoring(ARAIM) availability CONTINUITY Fault Detection(FD) INTEGRITY Protectionl level Temporary correlation
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Comprehensive Integration of the Operational Principles of Diabetic Foot Therapeutic Devices with Technological Innovations
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作者 Jinting ZHOU Yanliang CHEN +3 位作者 Dongnian WU Lingjun HUANG Yao YAO Yu DIAO 《Medicinal Plant》 2025年第2期75-80,共6页
This paper offers a comprehensive overview of the operational principles of current therapeutic devices for diabetic foot management and further analyzes technological innovations and developmental trends,aiming to pr... This paper offers a comprehensive overview of the operational principles of current therapeutic devices for diabetic foot management and further analyzes technological innovations and developmental trends,aiming to promote research and development in the field of technological convergence.The ultimate goal is to enhance the cure rate for diabetic foot conditions and to decrease the incidence of amputations.The paper discusses the novel applications of ultrasound and optical therapeutic devices within the field of physiotherapy,the numerous advantages of chitosan dressings in biotechnology,the ongoing advancements and broader combined use of vacuum sealing drainage techniques,and the distinctive effects and innovations associated with micro-oxygen diffusion techniques.It thoroughly examines various technological mechanisms that facilitate wound healing,highlighting the clinical applications of ultrasonic atomized medicinal solutions,novel dressing graft copolymerization,continuous hypoxia diffusion,and the functions of vacuum drainage.These advancements facilitate the integration of drainage and dressing changes,with the potential to enhance the therapeutic effects of diabetic foot treatment and provide valuable insights for clinical application. 展开更多
关键词 Diabetic foot therapeutic device operational principle Technological innovation Technological convergence
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How Do Deep Learning Forecasting Models Perform for Surface Variables in the South China Sea Compared to Operational Oceanography Forecasting Systems?
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作者 Ziqing ZU Jiangjiang XIA +6 位作者 Xueming ZHU Marie DREVILLON Huier MO Xiao LOU Qian ZHOU Yunfei ZHANG Qing YANG 《Advances in Atmospheric Sciences》 2025年第1期178-189,共12页
It is fundamental and useful to investigate how deep learning forecasting models(DLMs)perform compared to operational oceanography forecast systems(OFSs).However,few studies have intercompared their performances using... It is fundamental and useful to investigate how deep learning forecasting models(DLMs)perform compared to operational oceanography forecast systems(OFSs).However,few studies have intercompared their performances using an identical reference.In this study,three physically reasonable DLMs are implemented for the forecasting of the sea surface temperature(SST),sea level anomaly(SLA),and sea surface velocity in the South China Sea.The DLMs are validated against both the testing dataset and the“OceanPredict”Class 4 dataset.Results show that the DLMs'RMSEs against the latter increase by 44%,245%,302%,and 109%for SST,SLA,current speed,and direction,respectively,compared to those against the former.Therefore,different references have significant influences on the validation,and it is necessary to use an identical and independent reference to intercompare the DLMs and OFSs.Against the Class 4 dataset,the DLMs present significantly better performance for SLA than the OFSs,and slightly better performances for other variables.The error patterns of the DLMs and OFSs show a high degree of similarity,which is reasonable from the viewpoint of predictability,facilitating further applications of the DLMs.For extreme events,the DLMs and OFSs both present large but similar forecast errors for SLA and current speed,while the DLMs are likely to give larger errors for SST and current direction.This study provides an evaluation of the forecast skills of commonly used DLMs and provides an example to objectively intercompare different DLMs. 展开更多
关键词 forecast error deep learning forecasting model operational oceanography forecasting system VALIDATION intercomparison
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Intelligent Operational Decision-Making in Industrial Process:Development and Prospects
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作者 Tianyou Chai Siyu Cheng 《Engineering》 2025年第9期40-52,共13页
Based on an analysis of the role of industrial control and optimization technologies in the Industrial Revolution,as well as the current situation and existing problems of operational decision-making(ODM)for industria... Based on an analysis of the role of industrial control and optimization technologies in the Industrial Revolution,as well as the current situation and existing problems of operational decision-making(ODM)for industrial process,this paper introduces the concept of intelligent ODM in industrial process,shapes its future directions,and highlights key technical challenges.By the tight conjoining of and coordination between industrial artificial intelligence(AI)with industrial control and optimization technologies,as well as the Industrial Internet with industrial computer management and control systems,an intelligent operational optimization decision-making methodology is proposed for complex industrial process.The intelligent ODM methodology and its successful application demonstrate that the tight conjoining of and coordination between next-generation information technologies with industrial control and optimization technologies will promote the development of industrial intelligent ODM.Finally,main research directions and ideas are outlined for realizing intelligent ODM in industrial process. 展开更多
关键词 operational decision-making INTELLIGENCE Industrial artificial intelligence Industrial Internet Complex industrial process
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Advantages of the single-center model in domino transplant processes:Operational planning and management experience
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作者 Amil Huseynov Sevim Nuran KuşluÇicek Murat Tuncer 《World Journal of Clinical Cases》 2025年第16期9-17,共9页
BACKGROUND Kidney transplantation is one of the most effective treatments for patients with end-stage renal disease.However,many regions face low deceased donor rates and limited ABO-compatible transplant availability... BACKGROUND Kidney transplantation is one of the most effective treatments for patients with end-stage renal disease.However,many regions face low deceased donor rates and limited ABO-compatible transplant availability,which increases reliance on living donors.These regional challenges necessitate the implementation of kidney paired donation(KPD)programs to overcome incompatibilities such as ABO mismatch or positive cross-matching,even when suitable and willing donors are available.AIM To evaluate the effectiveness of a single-center domino KPD model in both operational planning and clinical management processes and to assess its impact on clinical outcomes.METHODS Between April 2020 and January 2024,we retrospectively evaluated patients enrolled in our center’s domino kidney transplantation program.Donor-recipient pairs unable to proceed due to ABO incompatibility or positive cross-matching with their own living donors were included.Donors and recipients were assessed based on blood group compatibility,HLA tissue typing,and negative cross-match results.A specialized computer algorithm grouped patients into three-way,fourway,and five-way chains.All surgical procedures were performed on the same day at a single center.RESULTS A total of 169 kidney transplants were performed,forming 52 domino chains.These domino KPD transplants accounted for a notable proportion of our center’s overall transplant activity,which included both living donor kidney transplants and deceased donor transplants.Among these chains,the primary reasons for participation were ABO incompatibility(74%),positive cross-matching(10%),and the desire to improve HLA mismatch(16%).Improved HLA mismatch profiles and high graft survival(96%at 1 year,92%at 3 years)and patient survival(98%at 1 year,94%at 3 years)rates were observed,as well as low acute rejection episodes.CONCLUSION The single-center domino KPD model enhanced transplant opportunities for incompatible donor-recipient pairs while maintaining excellent clinical outcomes.By providing a framework that addresses regional challenges,improves operational efficiency,and optimizes clinical management,this model offers actionable insights to reduce waiting lists and improve patient outcomes. 展开更多
关键词 Kidney paired donation Domino transplantation Single-center model operational planning Altruistic donors
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