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Hybrid Controller for Steady Speed of Agricultural Machinery on Slopes
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作者 WU Caicong XU Haisong GAO Xingyu 《农业机械学报》 北大核心 2026年第2期416-426,共11页
Steady speed control of agricultural machinery can improve operating quality and efficiency.To address the impact of farmland slope variations on the speed stability of unmanned operation agricultural machinery,a hybr... Steady speed control of agricultural machinery can improve operating quality and efficiency.To address the impact of farmland slope variations on the speed stability of unmanned operation agricultural machinery,a hybrid control method was proposed.This method included a hybrid controller composed of a slope-based controller and a proportional-integral-derivative(PID)controller.The speed of agricultural machinery was influenced by longitudinal forces,which were divided into two parts:one part was slope-related forces and conventional resistance,and the other was hard-to-estimate forces,such as sliding friction.For the first part,a slope-based controller was designed;for the second part,a PID controller was implemented.By combining these two controllers,the system can dynamically adjust the throttle opening and the brake master cylinder pressure,ensuring steady speed travel on sloping farmland.Simulation tests at a target speed of 7 km/h demonstrated that the proposed controller maintained a stable speed,achieving a root mean square error of 0.13 km/h and a mean absolute percentage error of 1.6%.Field tests on a practical experimental platform validated the method’s effectiveness,with results showing consistent control performance across varying slope conditions.The proposed controller demonstrated superior control performance.Experimental data verified that this method can achieve precise control of the agricultural machinery’s movement speed,meeting the stability requirements for agricultural operations. 展开更多
关键词 farmland slope PID controller steady speed control agricultural machinery unmanned operation
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Cooperative robust parallel operation of multiple actuators
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作者 XU Liang XU Xiang LIU Tao 《控制理论与应用》 北大核心 2026年第1期3-11,共9页
This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based... This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based on the internal model principle,a distributed dynamic output feedback control law is proposed to achieve both robust output regulation of the closed-loop system and plant input sharing among the actuators.A practical example of five motors cooperatively driving an uncertain shaft under an external load torque is presented to show the effectiveness of the proposed control law. 展开更多
关键词 cooperative parallel operation multiple actuators robust output regulation CONSENSUS
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Dexamethasone for prevention of AMS,HACE,and HAPE and for limiting impairment of performance after rapid ascent to high altitude:a narrative review
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作者 Johannes Burtscher Hannes Gatterer +1 位作者 Beth A.Beidleman Martin Burtscher 《Military Medical Research》 2026年第1期159-168,共10页
Acute exposure to high altitude can cause acute altitude illnesses and is associated with impaired cognitive and physical performance.The most effective preventive strategies currently recommended include environmenta... Acute exposure to high altitude can cause acute altitude illnesses and is associated with impaired cognitive and physical performance.The most effective preventive strategies currently recommended include environmental acclimatization(slow ascent and/or pre-acclimatization)or pharmacological support of acclimatization using acetazolamide.However,these strategies are not practical for high-altitude exposures that require rapid and unplanned ascent,high physical and mental performance,such as rescue missions or military operations.Dexamethasone and other modulators of the glucocorticoid system take effect quickly and are effective alternatives for preventing acute altitude illnesses when rapidly ascending to high altitudes.As the efficacy of dexamethasone in preventing acute mountain illnesses remains controversial,a review of existing studies on the use of dexamethasone for the prevention of acute mountain sickness was conducted,aiming to determine the best strategy.Possible mechanisms of protection against acute altitude illnesses are discussed based on the results of clinical trials.The data indicate that dexamethasone is most effective at altitudes above 4000 m at doses of 8–16 mg/d.Appropriately designed and powered trials are needed to obtain more evidence-based results on the dosage and timing of dexamethasone administration,and to provide optimized recommendations for the application of this powerful pharmacological tool. 展开更多
关键词 Altitude illnesses PREVENTION DEXAMETHASONE Emergency Rescue mission Military operation
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A hierarchical and role-driven digital twin system with applications to complex chemical process operation
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作者 Xinyu Tao Runjie Yao +3 位作者 Lingyu Zhu Changrui Xie Muqian Zhang Xi Chen 《Chinese Journal of Chemical Engineering》 2026年第1期302-313,共12页
Digital twin technology brings more opportunities and challenges to chemical engineering in both academic and industry.A complex process could have multiple digitalization needs,including simulation,monitoring,operato... Digital twin technology brings more opportunities and challenges to chemical engineering in both academic and industry.A complex process could have multiple digitalization needs,including simulation,monitoring,operator training,etc.;thus,a hierarchical digital twin would be a comprehensive solution to that.In this study,a novel and general framework of the digital twin is proposed for operations in process industry.With the hierarchical structure,the framework can handle various tasks driven by different roles in process industry,including managers,engineers,and operators.To complete these tasks,the framework consists of three modules:OAS(Operation Analysis System),OMS(Operation Monitoring System),and OTS(Operator Training System).Each module focuses on one unique type of demand from the staff,as well as interactions among them enabling efficient data sharing.Based on the hierarchical framework,a digital twin system is applied for one complex industrial nitration process,which successfully enhances the operation efficiency and safety in several industrial scenarios with different demands. 展开更多
关键词 Digital twin Hierarchical framework Role-driven Process operation Process modeling&optimization Operator training system
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Motion Performance Analysis of Offshore Lifting for Wind-Fishery Integrated Aquaculture Net Cage Considering Multi-Body Coupling Effects
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作者 WANG Wanqi YU Tongshun +2 位作者 LU Peng ZHAO Hui TAO Wei 《南方能源建设》 2026年第1期1-15,共15页
[Objective]This study aims to investigate the multi-body hydrodynamic interaction mechanisms during offshore lifting operations of aquaculture net cages in wind-fishery integration systems.By integrating numerical sim... [Objective]This study aims to investigate the multi-body hydrodynamic interaction mechanisms during offshore lifting operations of aquaculture net cages in wind-fishery integration systems.By integrating numerical simulations and dynamic analysis methods,this study systematically investigates the coupled dynamic response characteristics during the cage-carrier vessel separation process to reveal its dynamic evolution patterns and key influence mechanisms.[Method]Based on potential flow theory,a fully coupled dynamic analysis model of crane vessel-net cage-semi-submersible barge was established for a marine ranch project in Guangdong.The complete lifting process was dynamically simulated using SESAM software.Five typical operating sea states were configured to investigate the influence of wave parameters on the system's motion response under combined wave-current-wind actions.[Result]The results demonstrate that wave period dominates the system stability.Under short-period conditions,the system maintains stable motion with relatively small horizontal relative displacements,while long-period conditions excite low-frequency resonance,leading to significant slow-drift motions.Vertical response analysis reveals that long-period waves cause severe relative displacement fluctuations between the cage and semi-submersible vessel,with actual displacement amplitudes doubling the preset safety target of 2.045 m.Quantitative analysis further indicates that when significant wave height increases from 1.0 m to 1.5 m,the actual displacement amplitude increases by approximately 20%relative to the target displacement of 2.045 m,demonstrating that its influence is significantly weaker than the displacement variations induced by wave period changes.The complete dynamic simulation successfully captures the continuous dynamic response characteristics during the lifting process.[Conclusion]This research clarifies the influence mechanisms of wave parameters on the cage lifting process,identifying wave period as the crucial factor for operational safety.An operation window assessment method incorporating multi-body coupling effects is established,proposing a safety criterion with peak period not exceeding six seconds as the core requirement.The findings provide theoretical foundation for safe installation of marine ranch net cages and offer valuable references for similar offshore lifting operations. 展开更多
关键词 wind-fishery integration offshore lifting hydrodynamic analysis multi-body coupling analysis motion response safe operation window
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Passing the baton
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作者 Scott K.Powers 《Sports Medicine and Health Science》 2026年第1期1-2,共2页
Sports Medicine and Health Science(SMHS)has a short but impressive history.Following two diligent years of preplanning,SMHS was founded in 2019 by Co-Editors-in-Chief Dr.J.Larry Durstine and Dr.Quansheng Su.Dr.J.Larry... Sports Medicine and Health Science(SMHS)has a short but impressive history.Following two diligent years of preplanning,SMHS was founded in 2019 by Co-Editors-in-Chief Dr.J.Larry Durstine and Dr.Quansheng Su.Dr.J.Larry Durstine is retiring from his position on December 31,2025 and I am honored to accept the role of Editor-in-Chief(EIC)of SMHS along with Dr.Su.I want to begin my term as EIC by thanking Dr.J.Larry Durstine for his hard work and excellent editorial leadership during the first six years of journal operation.My job as the new EIC of SMHS will be to build on the already established excellence of the journal. 展开更多
关键词 health science journal operation sports medicine health science smhs sports medicine Passing Baton editorial leadership
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Research on Operation Strategies of Trade Publishing Knowledge Service Platform Based on the SICAS Model:A Case Study of CITIC Academy
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作者 WANG Jun ZHOU Xiaoyi 《Cultural and Religious Studies》 2026年第1期13-21,共9页
Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.... Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.To address this issue,this paper employs a combined approach of theoretical analysis and case study,introducing the SICAS(Sense-Interest-Connection-Action-Share)user consumption behavior analysis model and selecting“CITIC Academy”as the case study subject.It systematically examines and summarizes the platform’s operational practices and specific strategies,aiming to offer strategic insights and practical references for the operational improvement and sustainable,high-quality development of trade publishing knowledge service platforms. 展开更多
关键词 trade publishing knowledge service platform SICAS model operation strategy CITIC Academy
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World’s First 20 MW Offshore Wind Turbine Powers Grid
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《ChinAfrica》 2026年第3期8-10,共3页
The world’s most powerful offshore wind turbine has begun feeding electricity into the grid off the coast of southeast China,marking a major technological leap in the country’s wind power industry.The colossal turbi... The world’s most powerful offshore wind turbine has begun feeding electricity into the grid off the coast of southeast China,marking a major technological leap in the country’s wind power industry.The colossal turbine,developed and installed by China Three Gorges Corp.(CTG),is located in the Phase II Liuao offshore wind farm,more than 30 km off the coast of Fujian in waters deeper than 40 metres.The 20-mw unit successfully completed commissioning and started operation on 5 February,CTG announced. 展开更多
关键词 wind power technological leap offshore wind turbine wind power industry operation commissioning China Three Gorges Corp
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Recent Advancements in the Optimization Capacity Configuration and Coordination Operation Strategy of Wind-Solar Hybrid Storage System 被引量:1
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作者 Hongliang Hao Caifeng Wen +5 位作者 Feifei Xue Hao Qiu Ning Yang Yuwen Zhang Chaoyu Wang Edwin E.Nyakilla 《Energy Engineering》 EI 2025年第1期285-306,共22页
Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longe... Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems. 展开更多
关键词 Electric-thermal hybrid storage modal decomposition multi-objective genetic algorithm capacity optimization allocation operation strategy
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Clinical observation on prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation 被引量:3
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作者 Yan-Mei Huang Dong Ouyang 《World Journal of Gastrointestinal Surgery》 2025年第1期209-216,共8页
BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different tre... BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different treatment options.AIM To analyze the clinical effect and prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation(RPH).METHODS A total of 100 patients with mixed hemorrhoids who visited our hospital from October 2022 to September 2023 were selected and randomly divided into the control group(n=50)and the treatment group(n=50)by rolling the dice.The procedure for prolapse and hemorrhoids(PPH)was adopted in the control group,while polidocanol foam injection+RPH was adopted in the treatment group.The therapeutic effects,operation time,wound healing time,hospital stay,pain situation(24 hours post-operative pain score,first defecation pain score),quality of life(QOL),incidence of complications(post-operative hemorrhage,edema,infection),incidence of anal stenosis 3 months post-operatively and recurrence rate 1 year post-operatively of the two groups were compared.RESULTS Compared with the control group,the total effective rate of treatment group was higher,and the difference was significant(P<0.05).The operation time/wound healing time/hospital stay in the treatment group were shorter than those in the control group(P<0.05).The pain scores at 24 hours after operation/first defecation pain score of the treatment group was significantly lower than those in the control group(P<0.05).After surgery,the QOL scores of the two groups decreased,with the treatment group having higher scores than that of the control group(P<0.05).Compared with the control group,the incidence of postoperative complications in the treatment group was lower,and the difference was significant(P<0.05);However,there was no significant difference in the incidence of postoperative bleeding between the two groups(P>0.05);There was no significant difference in the incidence of anal stenosis 3 months after operation and the recurrence rate 1 year after operation between the two groups(P>0.05).CONCLUSION For patients with mixed hemorrhoids,the therapeutic effect achieved by using polidocanol injection combined with RPH was better.The wounds of the patients healed faster,the postoperative pain was milder,QOL improved,and the incidence of complications was lower,and the short-term and long-term prognosis was good. 展开更多
关键词 Mixed hemorrhoids Polidocanol injection Automatic elastic thread ligation operation Postoperative hemorrhage The degree of pain Recurrent rate
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A novel method for measuring interaction among multiple objectives in reservoir operation using niche theory 被引量:1
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作者 Xiao-kuan Ni Zeng-chuan Dong +6 位作者 Wen-hao Jia Wen-zhuo Wang Wei Xie Hong-yi Yao Mu-feng Chen Tian-yan Zhang Zhuo-zheng Li 《Water Science and Engineering》 2025年第1期78-89,共12页
Accurate capture and presentation of the interactive feedback relationships among various objectives in multi-objective reservoir operation is essential for maximizing operational benefits.In this study,the niche theo... Accurate capture and presentation of the interactive feedback relationships among various objectives in multi-objective reservoir operation is essential for maximizing operational benefits.In this study,the niche theory of ecology was innovatively applied to the field of reservoir operation,and a novel state-relationship(S-R)measurement analysis method was developed for multi-objective reservoir operation.This method enables the study of interaction among multiple objectives.This method was used to investigate the relationship among the objectives of power generation,water supply,and ecological protection for cascade reservoir operation in the Wujiang River Basin in China.The results indicated that the ecological protection objective was the most competitive in acquiring and capturing resources like flow and water level,while the water supply objective was the weakest.Power generation competed most strongly with ecological protection and relatively weakly with water supply.These findings facilitate decision-making throughout the reservoir operation process in the region.The S-R method based on the niche theory is convenient,efficient,and intuitive,allowing for the quantification of feedback relationships among objectives without requiring the solution of the Pareto frontier of a multi-objective problem in advance.This method provides a novel and feasible idea for studying multi-objective interactions. 展开更多
关键词 NICHE Interaction relationship Reservoir operation Multi-objective optimization Wujiang river
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Fault-tolerant control strategies for tilt-rotor aerial-aquatic vehicles:Design and implementation 被引量:1
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作者 Sihuan Wu Sifan Wu +3 位作者 Maosen Shao Zhilin He Yuan Liu Jinxiu Zhang 《Defence Technology(防务技术)》 2025年第9期274-293,共20页
The cross-domain capabilities of aerial-aquatic vehicles(AAVs)hold significant potential for future airsea integrated combat operations.However,the failure rate of AAVs is higher than that of unmanned systems operatin... The cross-domain capabilities of aerial-aquatic vehicles(AAVs)hold significant potential for future airsea integrated combat operations.However,the failure rate of AAVs is higher than that of unmanned systems operating in a single medium.To ensure the reliable and stable completion of tasks by AAVs,this paper proposes a tiltable quadcopter AAV to mitigate the potential issue of rotor failure,which can lead to high-speed spinning or damage during cross-media transitions.Experimental validation demonstrates that this tiltable quadcopter AAV can transform into a dual-rotor or triple-rotor configuration after losing one or two rotors,allowing it to perform cross-domain movements with enhanced stability and maintain task completion.This enhancement significantly improves its fault tolerance and task reliability. 展开更多
关键词 Aerial-aquatic vehicle Tiltable quadcopter FAULT-TOLERANCE Cross-media operation
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Phase-change heterostructure with HfTe_(2)confinement sublayers for enhanced thermal efficiency and low-power operation through Joule heating localization 被引量:1
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作者 S.W.Park H.J.Lee +6 位作者 K.A.Nirmal T.H.Kim D.H.Kim J.Y.Choi J.S.Oh J.M.Joo T.G.Kim 《Journal of Materials Science & Technology》 2025年第1期104-114,共11页
Although phase-change random-access memory(PCRAM)is a promising next-generation nonvolatile memory technology,challenges remain in terms of reducing energy consumption.This is primarily be-cause the high thermal condu... Although phase-change random-access memory(PCRAM)is a promising next-generation nonvolatile memory technology,challenges remain in terms of reducing energy consumption.This is primarily be-cause the high thermal conductivities of phase-change materials(PCMs)promote Joule heating dissi-pation.Repeated phase transitions also induce long-range atomic diffusion,limiting the durability.To address these challenges,phase-change heterostructure(PCH)devices that incorporate confinement sub-layers based on transition-metal dichalcogenide materials have been developed.In this study,we engi-neered a PCH device by integrating HfTe_(2),which has low thermal conductivity and excellent stability,into the PCM to realize PCRAM with enhanced thermal efficiency and structural stability.HEAT sim-ulations were conducted to validate the superior heat confinement in the programming region of the HfTe_(2)-based PCH device.Moreover,electrical measurements of the device demonstrated its outstanding performance,which was characterized by a low RESET current(∼1.6 mA),stable two-order ON/OFF ratio,and exceptional cycling endurance(∼2×10^(7)).The structural integrity of the HfTe_(2)confinement sub-layer was confirmed using X-ray photoelectron spectroscopy and transmission electron microscopy.The material properties,including electrical conductivity,cohesive energy,and electronegativity,substantiated these findings.Collectively,these results revealed that the HfTe_(2)-based PCH device can achieve significant improvements in performance and reliability compared with conventional PCRAM devices. 展开更多
关键词 Phase-change random-access memory Phase-change heterostructure Thermal efficiency Thermal stability Low-power operation
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Current development and future prospects of multi-target assignment problem:A bibliometric analysis review 被引量:1
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作者 Shuangxi Liu Zehuai Lin +1 位作者 Wei Huang Binbin Yan 《Defence Technology(防务技术)》 2025年第1期44-59,共16页
The multi-target assignment(MTA)problem,a crucial challenge in command control,mission planning,and a fundamental research focus in military operations,has garnered significant attention over the years.Extensively stu... The multi-target assignment(MTA)problem,a crucial challenge in command control,mission planning,and a fundamental research focus in military operations,has garnered significant attention over the years.Extensively studied across various domains such as land,sea,air,space,and electronics,the MTA problem has led to the emergence of numerous models and algorithms.To delve deeper into this field,this paper starts by conducting a bibliometric analysis on 463 Scopus database papers using CiteSpace software.The analysis includes examining keyword clustering,co-occurrence,and burst,with visual representations of the results.Following this,the paper provides an overview of current classification and modeling techniques for addressing the MTA problem,distinguishing between static multi-target assignment(SMTA)and dynamic multi-target assignment(DMTA).Subsequently,existing solution algorithms for the MTA problem are reviewed,generally falling into three categories:exact algorithms,heuristic algorithms,and machine learning algorithms.Finally,a development framework is proposed based on the"HIGH"model(high-speed,integrated,great,harmonious)to guide future research and intelligent weapon system development concerning the MTA problem.This framework emphasizes application scenarios,modeling mechanisms,solution algorithms,and system efficiency to offer a roadmap for future exploration in this area. 展开更多
关键词 Multi-target assignment Offensive and defensive confrontation Cooperative operation Modeling mechanism Solution algorithm CiteSpace analysis
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Clinicopathological characteristics and surgical value of primary gastrointestinal lymphoma 被引量:1
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作者 Cong-Xian Yang Lin-Xiang Xu +4 位作者 Jing Liu Hui-Lian Qiao Zhi-Wei Dong Dan Jiang Guo-Li Gu 《World Journal of Gastrointestinal Oncology》 2025年第11期168-178,共11页
BACKGROUND Primary gastrointestinal lymphoma(PGIL)is a relatively uncommon clinical entity,exhibiting distinctive features including occult primary sites,nonspecific clinical presentations,and considerable diagnostic ... BACKGROUND Primary gastrointestinal lymphoma(PGIL)is a relatively uncommon clinical entity,exhibiting distinctive features including occult primary sites,nonspecific clinical presentations,and considerable diagnostic and therapeutic difficulties.Consequently,comprehensive clinical investigations into its clinicopathological characteristics and surgical intervention value are warranted to enhance dia-gnostic and therapeutic proficiency.AIM To investigate the clinicopathological characteristics and surgical significance of PGIL from a surgical perspective,providing a theoretical basis for optimizing diagnostic and therapeutic strategies.METHODS This study included 50 cases of PGIL treated by the General Surgery Department of the Chinese PLA Air Force Medical Center from June 2001 to March 2025.Data were extracted from the Electronic Medical Record system for retrospective analysis.A retrospective analysis was conducted on their epidemiological,clinical manifestations,imaging,pathological features,and treatment outcomes.Descriptive statistics were applied for data summarization,with continuous variables presented as frequencies and percentages.Correlations between variables were assessed using the Spearman rank correlation coefficient.RESULTS All cases had the gastrointestinal tract as the primary site.Abdominal pain was the most common initial symptom(52.0%),with 80.0%of patients experiencing pain during the course of the disease,and 38.0%experiencing hema-tochezia/melena or anemia.Computed tomography diagnosis exhibited a high overall sensitivity(94.3%);the en-doscopic detection rate was 91.5%.Diffuse large B-cell lymphoma was the most common subtype(52.0%).The im-provement rate was higher in the surgery combined with chemotherapy group than in the chemotherapy only group.The incidence of postoperative complications was 26.5%,all occurring in patients with tumors>5 cm.CONCLUSION Diffuse large B-cell lymphoma is the primary PGIL subtype.Imaging and endoscopic biopsy are diagnostic es-sentials.Surgery aids in resection,complication management,and pathologic diagnosis.Multidisciplinary,indi-vidualized strategies are recommended,necessitating further prospective molecular studies. 展开更多
关键词 Gastrointestinal lymphoma Multimodal diagnostics Clinical characteristics Surgical operation Multimodal diagnostics
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Capacity matching and optimization of solarground source heat pump coupling systems 被引量:1
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作者 Jing-hui Luo Yun-xin Huang +4 位作者 Jing-gang Wang Wei Liu Wen-hong Wang Zi-chen Han Chang-jian Zhang 《Applied Geophysics》 2025年第3期739-750,895,共13页
Ground source heat pump systems demonstrate significant potential for northern rural heating applications;however,the effectiveness of these systems is often limited by challenging geological conditions.For instance,i... Ground source heat pump systems demonstrate significant potential for northern rural heating applications;however,the effectiveness of these systems is often limited by challenging geological conditions.For instance,in certain regions,the installation of buried pipes for heat exchangers may be complicated,and these pipes may not always serve as efficient low-temperature heat sources for the heat pumps of the system.To address this issue,the current study explored the use of solar-energy-collecting equipment to supplement buried pipes.In this design,both solar energy and geothermal energy provide low-temperature heat to the heat pump.First,a simulation model of a solar‒ground source heat pump coupling system was established using TRNSYS.The accuracy of this model was validated through experiments and simulations on various system configurations,including varying numbers of buried pipes,different areas of solar collectors,and varying volumes of water tanks.The simulations examined the coupling characteristics of these components and their influence on system performance.The results revealed that the operating parameters of the system remained consistent across the following configurations:three buried pipes,burial depth of 20 m,collector area of 6 m^(2),and water tank volume of 0.5 m^(3);four buried pipes,burial depth of 20 m,collector area of 3 m^(2),and water tank volume of 0.5 m^(3);and five buried pipes with a burial depth of 20 m.Furthermore,the heat collection capacity of the solar collectors spanning an area of 3 m^(2)was found to be equivalent to that of one buried pipe.Moreover,the findings revealed that the solar‒ground source heat pump coupling system demonstrated a lower annual cumulative energy consumption compared to the ground source heat pump system,presenting a reduction of 5.31%compared to the energy consumption of the latter. 展开更多
关键词 solar‒ground source heat pump coupling system OPTIMIZATION TRNSYS energy-saving operation matching design
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A New Encryption Mechanism Supporting the Update of Encrypted Data for Secure and Efficient Collaboration in the Cloud Environment
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作者 Chanhyeong Cho Byeori Kim +1 位作者 Haehyun Cho Taek-Young Youn 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期813-834,共22页
With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly increased.However,traditional collaboration tools primarily rely on access control,leaving data stored on cloud... With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly increased.However,traditional collaboration tools primarily rely on access control,leaving data stored on cloud servers vulnerable due to insufficient encryption.This paper introduces a novel mechanism that encrypts data in‘bundle’units,designed to meet the dual requirements of efficiency and security for frequently updated collaborative data.Each bundle includes updated information,allowing only the updated portions to be reencrypted when changes occur.The encryption method proposed in this paper addresses the inefficiencies of traditional encryption modes,such as Cipher Block Chaining(CBC)and Counter(CTR),which require decrypting and re-encrypting the entire dataset whenever updates occur.The proposed method leverages update-specific information embedded within data bundles and metadata that maps the relationship between these bundles and the plaintext data.By utilizing this information,the method accurately identifies the modified portions and applies algorithms to selectively re-encrypt only those sections.This approach significantly enhances the efficiency of data updates while maintaining high performance,particularly in large-scale data environments.To validate this approach,we conducted experiments measuring execution time as both the size of the modified data and the total dataset size varied.Results show that the proposed method significantly outperforms CBC and CTR modes in execution speed,with greater performance gains as data size increases.Additionally,our security evaluation confirms that this method provides robust protection against both passive and active attacks. 展开更多
关键词 Cloud collaboration mode of operation data update efficiency
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Hourglass-GCN for 3D Human Pose Estimation Using Skeleton Structure and View Correlation
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作者 Ange Chen Chengdong Wu Chuanjiang Leng 《Computers, Materials & Continua》 SCIE EI 2025年第1期173-191,共19页
Previous multi-view 3D human pose estimation methods neither correlate different human joints in each view nor model learnable correlations between the same joints in different views explicitly,meaning that skeleton s... Previous multi-view 3D human pose estimation methods neither correlate different human joints in each view nor model learnable correlations between the same joints in different views explicitly,meaning that skeleton structure information is not utilized and multi-view pose information is not completely fused.Moreover,existing graph convolutional operations do not consider the specificity of different joints and different views of pose information when processing skeleton graphs,making the correlation weights between nodes in the graph and their neighborhood nodes shared.Existing Graph Convolutional Networks(GCNs)cannot extract global and deeplevel skeleton structure information and view correlations efficiently.To solve these problems,pre-estimated multiview 2D poses are designed as a multi-view skeleton graph to fuse skeleton priors and view correlations explicitly to process occlusion problem,with the skeleton-edge and symmetry-edge representing the structure correlations between adjacent joints in each viewof skeleton graph and the view-edge representing the view correlations between the same joints in different views.To make graph convolution operation mine elaborate and sufficient skeleton structure information and view correlations,different correlation weights are assigned to different categories of neighborhood nodes and further assigned to each node in the graph.Based on the graph convolution operation proposed above,a Residual Graph Convolution(RGC)module is designed as the basic module to be combined with the simplified Hourglass architecture to construct the Hourglass-GCN as our 3D pose estimation network.Hourglass-GCNwith a symmetrical and concise architecture processes three scales ofmulti-viewskeleton graphs to extract local-to-global scale and shallow-to-deep level skeleton features efficiently.Experimental results on common large 3D pose dataset Human3.6M and MPI-INF-3DHP show that Hourglass-GCN outperforms some excellent methods in 3D pose estimation accuracy. 展开更多
关键词 3D human pose estimation multi-view skeleton graph elaborate graph convolution operation Hourglass-GCN
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“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage
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作者 Yan Zhao Qiang Yuan +5 位作者 Liting Yang Guisheng Liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期348-360,共13页
Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(gen... Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term cyclability.Here,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical properties.During Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O movement.Such superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries. 展开更多
关键词 NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization
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Design of broadband achromatic far-infrared metalens based on chalcogenide glass using parameterized topology optimization
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作者 ZHOU Yun-fei ZOU Lin-er +1 位作者 CHENG Yang-bing SHEN Yun 《中国光学(中英文)》 北大核心 2025年第6期1475-1483,共9页
Metalens technology has been applied extensively in miniaturized and integrated infrared imaging systems.However,due to the high phase dispersion of unit structures,metalens often exhibits chromatic aberration,making ... Metalens technology has been applied extensively in miniaturized and integrated infrared imaging systems.However,due to the high phase dispersion of unit structures,metalens often exhibits chromatic aberration,making broadband achromatic infrared imaging challenging to achieve.In this paper,six different unit structures based on chalcogenide glass are constructed,and their phase-dispersion parameters are analyzed to establish a database.On this basis,using chromatic aberration compensation and parameterized adjoint topology optimization,a broadband achromatic metalens with a numerical aperture of 0.5 is designed by arranging these six unit structures in the far-infrared band.Simulation results show that the metalens achieves near diffraction-limited focusing within the operating wavelength range of 9−11μm,demonstrating the good performance of achromatic aberration with flat focusing efficiency of 54%−58%across all wavelengths. 展开更多
关键词 metalens chalcogenide glass topology optimization high efficiency long wave infrared broadband operation
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