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Adaptive-length data-driven predictive control for post-operation of space robot non-cooperative target capture with disturbances 被引量:1
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作者 Peiji WANG Bicheng CAI +2 位作者 Chengfei YUE Yong ZHAO Weiren WU 《Chinese Journal of Aeronautics》 2026年第2期485-498,共14页
This paper solves the problem of model-free dual-arm space robot maneuvering after non-cooperative target capture under high control quality requirements.The explicit system model is unavailable,and the maneuvering mi... This paper solves the problem of model-free dual-arm space robot maneuvering after non-cooperative target capture under high control quality requirements.The explicit system model is unavailable,and the maneuvering mission is disturbed by the measurement noise and the target adversarial behavior.To address these problems,a model-free Combined Adaptive-length Datadriven Predictive Controller(CADPC)is proposed.It consists of a separated subsystem identification method and a combined predictive control strategy.The subsystem identification method is composed of an adaptive data length,thereby reducing sensitivity to undetermined measurement noises and disturbances.Based on the subsystem identification,the combined predictive controller is established,reducing calculating resource.The stability of the CADPC is rigorously proven using the Input-to-State Stable(ISS)theorem and the small-gain theorem.Simulations demonstrate that CADPC effectively handles the model-free space robot post operation in the presence of significant disturbances,state measurement noise,and control input errors.It achieves improved steady-state accuracy,reduced steady-state control consumption,and minimized control input chattering. 展开更多
关键词 Combined control Data-driven predictive control Post operation Predictive control systems Space non-cooperative target capture
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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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Dependable dynamic capacity provision of wind-storage plants
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作者 Ziqi Shen Wei Wei +2 位作者 Zhongjie Guo Laijun Chen Shengwei Mei 《iEnergy》 2026年第1期55-70,共16页
Although wind energy is volatile,the output of a wind-storage plant is partially dispatchable,making it a promising paradigm on the generation side.A grid-friendly wind-storage plant ought to be able to continuously o... Although wind energy is volatile,the output of a wind-storage plant is partially dispatchable,making it a promising paradigm on the generation side.A grid-friendly wind-storage plant ought to be able to continuously output the desired power over a certain period of time.This paper proposes a dependable dynamic capacity provision scheme of a wind-storage plant over a daily horizon.It stipulates a minimum number of periods during which the committed capacity must be fulfilled and a maximum mismatch during the remaining periods when the desired power output is not achievable.In the general case,the day-ahead piecewise constant capacity provision results in a two-stage stochastic program formulated as a mixed-integer linear program.Specifically,for constant capacity provision,a decomposition algorithm is developed to determine the global optimal solution,and the complexity grows linearly with the number of scenarios.Given the committed capacity trajectory,the real-time operation problem is modeled as a four-state stochastic dynamic program.The discrete state-action values are derived recursively via the principle of optimality.Real-time dispatch actions are generated by using the action-value tabular leveraging inexact ultra-short-term forecasts.Numerical tests over one year demonstrate that the proposed method successfully fulfills reliable operation on 355 days and achieve an optimality gap of 9.47%compared with the ex-post optimum,which is comparable to model predictive control using exact 2–3-hour-ahead wind power forecasts. 展开更多
关键词 Wind power Energy storage Dynamic capacity provision Real-time operation
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FENet:Underwater Image Enhancement via Frequency Domain Enhancement and Edge-Guided Refinement
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作者 Xinwei Zhu Jianxun Zhang Huan Zeng 《Computers, Materials & Continua》 2026年第2期1942-1966,共25页
Underwater images often affect the effectiveness of underwater visual tasks due to problems such as light scattering,color distortion,and detail blurring,limiting their application performance.Existing underwater imag... Underwater images often affect the effectiveness of underwater visual tasks due to problems such as light scattering,color distortion,and detail blurring,limiting their application performance.Existing underwater image enhancement methods,although they can improve the image quality to some extent,often lead to problems such as detail loss and edge blurring.To address these problems,we propose FENet,an efficient underwater image enhancement method.FENet first obtains three different scales of images by image downsampling and then transforms them into the frequency domain to extract the low-frequency and high-frequency spectra,respectively.Then,a distance mask and a mean mask are constructed based on the distance and magnitude mean for enhancing the high-frequency part,thus improving the image details and enhancing the effect by suppressing the noise in the low-frequency part.Affected by the light scattering of underwater images and the fact that some details are lost if they are directly reduced to the spatial domain after the frequency domain operation.For this reason,we propose a multi-stage residual feature aggregation module,which focuses on detail extraction and effectively avoids information loss caused by global enhancement.Finally,we combine the edge guidance strategy to further enhance the edge details of the image.Experimental results indicate that FENet outperforms current state-of-the-art underwater image enhancement methods in quantitative and qualitative evaluations on multiple publicly available datasets. 展开更多
关键词 Detail extraction frequency domain operation edge guidance image enhancement
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Preparation of digital-encoded and analog-encoded quantum states corresponding to matrix operations
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作者 Kaitian Gao Youlong Yang Zhenye Du 《Chinese Physics B》 2026年第1期332-344,共13页
Efficient implementation of fundamental matrix operations on quantum computers,such as matrix products and Hadamard operations,holds significant potential for accelerating machine learning algorithms.A critical prereq... Efficient implementation of fundamental matrix operations on quantum computers,such as matrix products and Hadamard operations,holds significant potential for accelerating machine learning algorithms.A critical prerequisite for quantum implementations is the effective encoding of classical data into quantum states.We propose two quantum computing frameworks for preparing the distinct encoded states corresponding to matrix operations,including the matrix product,matrix sum,matrix Hadamard product and division.Quantum algorithms based on the digital encoding computing framework are capable of implementing the matrix Hadamard operation with a time complexity of O(poly log(mn/ε))and the matrix product with a time complexity of O(poly log(mnl/ε)),achieving an exponential speedup in contrast to the classical methods of O(mn)and O(mnl).Quantum algorithms based on the analog-encoding framework are capable of implementing the matrix Hadamard operation with a time complexity of O(k_(1)√mn·poly log(mn/ε))and the matrix product with a time complexity of O(k_(2)√1·poly log(mnl/ε)),where k_(1)and k_(2)are coefficients correlated with the elements of the matrix,achieving a square speedup in contrast to the classical counterparts.As applications,we construct an oracle that can access the trace of a matrix within logarithmic time,and propose several algorithms to respectively estimate the trace of a matrix,the trace of the product of two matrices,and the trace inner product of two matrices within logarithmic time. 展开更多
关键词 quantum algorithm matrix operation digital and analog-encoded states quantum computing
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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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Hardware-Algorithm Co-Design:SiC Bidirectional Converters with MPC-Fuzzy Logic Control for Robust Operation of Solar-Powered EV Hubs
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作者 Wan Chen Zhi Liu +6 位作者 Yingxue Ma Cuicui Wang Xinfa Gu Baolian Liu Lei Shen Hui Huang Jie Ji 《Energy Engineering》 2026年第3期96-116,共21页
In order to solve the problems of slow dynamic response and difficult multi-source coordination of solar electric vehicle charging stations under intermittent renewable energy,this paper proposes a hardware-algorithm ... In order to solve the problems of slow dynamic response and difficult multi-source coordination of solar electric vehicle charging stations under intermittent renewable energy,this paper proposes a hardware-algorithm co-design framework:the T-type three-level bidirectional converter(100 kHz switching frequency)based on silicon carbide(SiC)MOSFET is deeply integrated with fuzzy model predictive control(Fuzzy-MPC).At the hardware level,the switching trajectory and resonance suppression circuit(attenuation resonance peak 18 dB)are optimized,and the total loss is reduced by 23%compared with the traditional silicon-based IGBT.At the algorithm level,the adaptive parameter update mechanism and multi-objective rolling optimization are adopted,and the 5 ms level dynamic power allocation is realized by relying on edge computing.Experiments on 800 V DC microgrid(including 600 kW photovoltaic and 150 A·h energy storage)built based on MATLAB/Simulink hardware-in-the-loop(HIL)platform show that the system shortens the battery charging time from 42 to 28 min(the charging speed is increased by 33%).Through the 78%valley power utilization rate,the power purchase cost of high-priced power grids was significantly reduced,and the levelized electricity price decreased by 10.3%;Under the irradiation fluctuation,the renewable energy consumption rate increases by 10.1%,and the DC bus voltage fluctuation is stable within±10 V when the load step is±30%.The co-design provides an economically feasible and dynamically robust solution for the efficient integration of PV-ESG-EV in the smart grid. 展开更多
关键词 Power electronics co-design fuzzy-MPC control T-type three-level converter grid-adaptive operation PV-storage-charging integration switching loss compensation
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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:4
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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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