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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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Effect of Argon Atmosphere Heat Treatment on Mechanical Properties and Microstructural Evolution of Shicolon-Ⅱ SiC Fibers
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作者 YUAN Wang HU Jianbao +3 位作者 ZHOU Liang KAN Yanmei ZHANG Xiangyu DONG Shaoming 《无机材料学报》 北大核心 2026年第1期119-128,共10页
Silicon carbide fibers are considered ideal reinforcing materials for ceramic matrix composites due to their excellent mechanical properties and high-temperature performance.Different types of fibers necessitate indiv... Silicon carbide fibers are considered ideal reinforcing materials for ceramic matrix composites due to their excellent mechanical properties and high-temperature performance.Different types of fibers necessitate individual investigation due to variations in their composition and fabrication processes.This study presents a comprehensive investigation into evolution of the mechanical properties,surface microstructure,and composition of Shicolon-Ⅱ fibers subjected to argon heat treatment at temperatures ranging from 1300℃to 1700℃.The Shicolon-Ⅱ fibers are composed of small-sized β-SiC grains,SiC_(x)O_(y) amorphous phase,and a minor amount of graphite microcrystals.Following treatment in an argon atmosphere at 1300℃,the fibers maintain a monofilament tensile strength of 3.620 GPa,corresponding to a retention of 98.32%.This strength diminishes to 2.875 GPa,equating to a retention of 78.08%,after treatment at 1500℃.The reduction in mechanical properties of the fibers can be ascribed to the decomposition of the amorphous phase and the growth of β-SiC grains.Furthermore,creep resistance is an essential factor influencing the long-term performance of composite materials.After treatment at temperatures above 1400℃,the high-temperature creep resistance of the fibers is significantly enhanced due to growth of β-SiC grains.This study offers valuable theoretical insights into high-temperature applications of second-generation fibers,contributing to an enhanced understanding of their performance under extreme conditions. 展开更多
关键词 Shicolon-ⅡSiC fiber heat treatment mechanical property MICROSTRUCTURE
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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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Lines Across Horizons Hainan's island-wide special customs operations are redefining boundaries to elevate opening-up
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作者 Yang Hangjun 《China Report ASEAN》 2026年第3期16-19,共4页
On December 18,2025, Hainan Free Trade Port (Hainan FTP) officially began islandwide special customs operations.Although only two months have passed since this landmark step, the shift is already visible everywhere—f... On December 18,2025, Hainan Free Trade Port (Hainan FTP) officially began islandwide special customs operations.Although only two months have passed since this landmark step, the shift is already visible everywhere—from the bustling flow of international passengers at Haikou Meilan International Airport to the steady stream of cargo vessels calling at Yangpu Port, and even in the sustained attention investors are paying to “Hainan-related” stocks.Together, these signals point to one clear conclusion:China’s largest special economic zone has entered a new phase of development. 展开更多
关键词 free trade port Special Customs operations Hainan Free Trade Port Islandwide Special Customs operations International Passengers cargo vessels INVESTORS Opening up
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Regulation of Microstructure,Mechanical Properties,and Corrosion Properties of Laser-Melting-Deposited B_(4)C/TC4 Composite by Heat Treatment
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作者 Zhao Cenya Zheng Yang +4 位作者 Xiong Ruize Ji Wenkang Zhang Daohong Liu Wei Tao Hailin 《稀有金属材料与工程》 北大核心 2026年第2期285-291,共7页
The TiB+TiC dual-reinforced B_(4)C/TC4 composite was in-situ fabricated via incorporating 0.5wt%B_(4)C reinforcement during the laser melting deposition process.Different heat treatments of annealing and solid solutio... The TiB+TiC dual-reinforced B_(4)C/TC4 composite was in-situ fabricated via incorporating 0.5wt%B_(4)C reinforcement during the laser melting deposition process.Different heat treatments of annealing and solid solution were used to regulate the microstructure,mechanical properties,and corrosion properties of B_(4)C/TC4 composite.Results show that with the increase in temperature from 500℃to 800°C,partial lamellarα-Ti in the as-deposited sample is gradually transformed into equiaxedα-Ti,accompanied by the disappearance of basketweave microstructure.At 1100°C,a small portion of TiC phase suffers fusion.This composite exhibits the optimal combination of strength and plasticity after annealing at 500℃for 4 h followed by furnace cooling,which is attributed to the stress release effect and the refined basketweave microstructure.However,this composite shows a decline in corrosion resistance after various heat treatments due to grain coarsening and micro-galvanic corrosion. 展开更多
关键词 B_(4)C/TC4 composite laser melting deposition heat treatment mechanical property corrosion property
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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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Splitting of Operations for Di-Associative Algebras and Tri-Associative Algebras
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作者 Wen TENG Xiansheng DAI 《Journal of Mathematical Research with Applications》 2026年第1期21-32,共12页
Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algeb... Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras. 展开更多
关键词 dendriform algebra di-associative algebra quad-dendriform algebra tri-associative algebra six-dendriform algebra relative averaging operator
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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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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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Gateway to China Hainan's special customs operations facilitate access to the Chinese market
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作者 Wang Junshan 《China Report ASEAN》 2026年第3期34-35,共2页
For ordinary tourists, simpler entry and exit procedures and a broader range of duty-free goods in Hainan create a better travel and shopping experience.For China’s earnest endeavor to deepen reform and opening-up, i... For ordinary tourists, simpler entry and exit procedures and a broader range of duty-free goods in Hainan create a better travel and shopping experience.For China’s earnest endeavor to deepen reform and opening-up, implementation of the special customs operations policy in Hainan represents a significant step forward. For businesses in Malaysia and other ASEAN member states, especially export-oriented small and medium-sized enterprises (SMEs), Hainan serves as a“transit hub” for accessing the Chinese market and even other Asian markets. 展开更多
关键词 SMEs simplified entry exit procedures duty free goods ASEAN special customs operations HAINAN Chinese market reform opening up
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Forging a New Trade Frontier The special customs operations in Hainan Free Trade Port are blazing new opportunities for inbound and outbound investment
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作者 Wang Ruohan 《China Report ASEAN》 2026年第3期26-27,共2页
With the gradual implementation of a series of institutional arrangements, H ainan is becoming a new hot spot for global investment and an ideal destination for starting businesses and developing industry. While attra... With the gradual implementation of a series of institutional arrangements, H ainan is becoming a new hot spot for global investment and an ideal destination for starting businesses and developing industry. While attracting foreign investment projects, it is also creating more favorable conditions for local enterprises to expand into international markets. 展开更多
关键词 global investment series institutional arrangements inbound investment trade frontier customs operations developing industry outbound investment institutional arrangements
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Sky's the Limit In Wenchang, commercial aerospace is soaring to new heights, propelled by Hainan FTP's island-wide special customs operations
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作者 Xia Yuanyuan 《China Report ASEAN》 2026年第3期30-31,共2页
At 11:00 p.m. on January 13, 2026, floodlights illuminated the launch pad at the Hainan Commercial Space Launch Site in Wenchang,south China’s Hainan Province. A Long March-8A (CZ-8A) carrier rocket lifted off with a... At 11:00 p.m. on January 13, 2026, floodlights illuminated the launch pad at the Hainan Commercial Space Launch Site in Wenchang,south China’s Hainan Province. A Long March-8A (CZ-8A) carrier rocket lifted off with a steady roar, its exhaust lighting up the night sky as it delivered a satellite into its designated orbit.The development of China’s first commercial space launch site has been striking. Since its inaugural launch in2024, it has completed 11 missions in less than 14 months—each a success. 展开更多
关键词 Long March space launch site satellite launch special customs operations commercial space launch launch pad Hainan Wenchang commercial aerospace
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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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Endovascular treatment of delayed arterial hemorrhage after radical operation for hilar cholangiocarcinoma 被引量:1
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作者 Xiang-Dong Wang Nai-Jian Ge +3 位作者 Cheng-Jian He Jun-Jun Zhu Wei Xu Ye-Fa Yang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第4期403-405,共3页
Radical operation for hilar cholangiocarcinoma(HCCA)is the most effective treatment,but high rates of severe postoperative complication and death remain concerns due to the complexity of biliary and vascular anatomy o... Radical operation for hilar cholangiocarcinoma(HCCA)is the most effective treatment,but high rates of severe postoperative complication and death remain concerns due to the complexity of biliary and vascular anatomy of the hepatobiliary region.De-layed arterial hemorrhage(DAH)occurring>24 h postoperatively usually causes life-threatening bleeding,and relaparotomy for DAH would be difficult and hazardous because of postoperative adhe-sions and critical general condition.As endovascular technique is less invasive and has improved over the recent decades,clini-cians have begun to prefer endovascular treatment(EVT)to surgi-cal treatment of DAH after hepatobiliary pancreatic surgery.How-ever,to our knowledge,a relatively large series of patients dealing with the outcomes of EVT of DAH after surgery for HCCA has not been reported.Herein,we analyzed the technical and clinical out-comes of EVT in 17 patients to evaluate the efficacy and safety of EVT. 展开更多
关键词 operation ARTERIAL HEMORRHAGE treatment AFTER
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Three-dimensional virtual operations can facilitate complicated surgical planning for the treatment of patients with jaw deformities associated with facial asymmetry: a case report 被引量:6
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作者 Shingo Hara Masaharu Mitsugi +3 位作者 Takahiro Kanno Akihiko Nomachi Takehiko Wajima Yukihiro Tatemoto 《International Journal of Oral Science》 SCIE CAS CSCD 2013年第3期176-182,共7页
This article describes a case we experienced in which good postsurgical facial profiles were obtained for a patient with jaw deformities associated with facial asymmetry,by implementing surgical planning with SimPlant... This article describes a case we experienced in which good postsurgical facial profiles were obtained for a patient with jaw deformities associated with facial asymmetry,by implementing surgical planning with SimPlant OMS.Using this method,we conducted LF1 osteotomy,intraoral vertical ramus osteotomy(IVRO),sagittal split ramus osteotomy(SSRO),mandibular constriction and mandibular border genioplasty.Not only did we obtain a class I occlusal relationship,but the complicated surgery also improved the asymmetry of the frontal view,as well as of the profile view,of the patient.The virtual operation using three-dimensional computed tomography(3D-CT)could be especially useful for the treatment of patients with jaw deformities associated with facial asymmetry. 展开更多
关键词 facial asymmetry mnandibular constriction transverse discrepancy of the dental arch width virtual operation
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Pilot-scale experiments on multilevel contact oxidation treatment of poultry farm wastewater using saran lock carriers under different operation model 被引量:3
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作者 Tianlong Zheng Peng Li +4 位作者 Xiaoyu Ma Xiaohong Sun Chuanfu Wu Qunhui Wang Ming Gao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第3期336-345,共10页
A pilot-scale multilevel contact oxidation reactors system, coupled with saran lock carriers,was applied for the treatment of poultry farm wastewater. The removal efficiencies of CODcr, ammonia, and the total nitrogen... A pilot-scale multilevel contact oxidation reactors system, coupled with saran lock carriers,was applied for the treatment of poultry farm wastewater. The removal efficiencies of CODcr, ammonia, and the total nitrogen as well as the elimination performance of CODcr and total nitrogen along the three-level contact oxidation tanks under six designed operational models were investigated. Based on the performance of the nitrogen removal of the saran lock carriers and the distribution of anoxic–aerobic interspace under the suitable operation model, the mechanism of nitrogen removal of the system was also explored. The results revealed that the intermittent aeration under parallel model is the most suitable operation model, while the removal efficiencies of CODcr, ammonia, and the total nitrogen were 86.86%, 84.04%, and 80.96%, respectively. The effluent concentration of CODcr,ammonia, and the total nitrogen were 55.6 mg/L, 8.3 mg/L, and 12.0 mg/L, which satisfy both the discharge standard of pollutants for livestock and poultry breeding industry(GB18596–2001) and the first grade of the integrated wastewater discharge standard(GB 8978–1996). Moreover, the mechanism for the nitrogen removal should be attributed to the plenty of anoxic–aerobic interspaces of the biofilm and the three-dimensional spiral structure of the saran lock carriers, where the oxygen-deficient distribution was suitable for the happening of the simultaneous nitrification and denitrification process. Therefore, the multilevel contact oxidation tanks system is an effective pathway for the treatment of the poultry farm wastewater on the strength of a suitable operation model and novel carriers. 展开更多
关键词 MULTILEVEL contact oxidation tanks Nitrogen removal Mechanism operation model POULTRY FARM WASTEWATER Saran LOCK carriers
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Synergistic improvement of mechanical and electromagnetic shielding properties of a Mg-Li-Y-Zn alloy following heat treatment 被引量:2
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作者 Jinsheng Li Liping Zhong +3 位作者 Junli Wang Zhongxue Feng Yan Qu Ruidong Xu 《Journal of Magnesium and Alloys》 2025年第3期1243-1257,共15页
The performances of magnesium alloys remain insufficient to further enhance the application potential of ultralight magnesium alloys.In this work,a Mg-8Li-3Y-2Zn alloy was prepared through vacuum melting and subsequent... The performances of magnesium alloys remain insufficient to further enhance the application potential of ultralight magnesium alloys.In this work,a Mg-8Li-3Y-2Zn alloy was prepared through vacuum melting and subsequent heat treatment at 300,450,and 500°C.The material properties of the resulting samples were assessed through microstructural observation,tensile testing,electrical conductivity measurements,and electromagnetic shielding effectiveness(EMI-SE)testing.The influence of the Mg-8Li-3Y-2Zn alloy microstructure on its mechanical and electromagnetic shielding properties in different states was investigated.It was found that the as-cast alloy containsα-Mg,β-Li,Mg_(3)Zn_(3)Y_(2),and Mg_(12)ZnY phases.Following heat treatment at 500℃(HT500),the blockα-Mg phase transformedfine needle-shapes,its tensile strength increased to 263.7 MPa,and its elongation reached 45.3%.The mechanical properties of the alloy were significantly improved by the synergistic effects imparted by the needle-shapedα-Mg phase,solid solution strengthening,and precipitation strengthening.The addition of Y and Zn improved the EMI-SE of Mg-8Li-1Zn alloy,wherein the HT500 sample exhibits the highest SE,maintaining a value of 106.7–76.9 dB in the frequency range of 30–4500 MHz;this performance has rarely been reported for electromagnetically shielded alloys.This effect was mainly attributed to the multiple reflections of electromagnetic waves caused by the severe impedance mismatch of the abundant phase boundaries,which were in turn provided by the dual-phase(α/β)and secondary phases.Furthermore,the presence of nano-precipitation was also believed to enhance the absorption of electromagnetic waves. 展开更多
关键词 Mg-Li alloy Microstructure Heat treatment Mechanical properties Electromagnetic shielding
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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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Achieving balanced mechanical properties in laser powder bed fusion processed Inconel 718 superalloy through a simplified heat treatment process 被引量:2
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作者 Ziyi Ding Kesong Miao +5 位作者 Qi Chao Xinliang Xie Xia Ji Hao Wu Xiaojun Wang Guohua Fan 《Journal of Materials Science & Technology》 2025年第15期54-70,共17页
Laser additively manufactured(LAM)Ni-based superalloys commonly exhibit low strength and high residual stress in the as-built state,requiring post-heat treatment to improve mechanical properties.We propose a modified ... Laser additively manufactured(LAM)Ni-based superalloys commonly exhibit low strength and high residual stress in the as-built state,requiring post-heat treatment to improve mechanical properties.We propose a modified heat treatment(MHT)process that only involves a single-step aging at 650℃ for 4 h to achieve high strength,high ductility,and low residual stress simultaneously in a laser powder bed fusion(LPBF)-processed Inconel 718(IN718)alloy.The MHT treated alloy exhibits comparable tensile strength(1368 MPa)to the conventional solution plus two-step aging(SA)treated alloy(1398 MPa),while the tensile elongation(∼21.7%for MHT treated alloy and 13.4%for SA treated alloy)is 60%higher and the residual stress(∼195 MPa)is 20%lower than the SA treated alloy.The balanced high performance of the MHT IN718 alloy was mainly attributed to the precipitation of abundantγ’’phase with a size of∼5 nm,while the original nano-sized Laves precipitates and dislocation cells were mostly retained.The finer size and higher fraction ofγ”of the MHT sample mainly result from the dislocation structure and compositional variations in the as-built IN718,which promotes precipitation during aging.The retention of Laves phase,and cellular dislocation network in the MHT alloy also contributes to work hardening during tension and suspends the occurrence of necking.This study unveils a unique strengthening and toughening mechanism in the Ni-based superalloy produced by LAM with the presence of abundant Laves precipitates and provides a simple,low energy-consumption and cost-effective heat treatment route for achieving desirable mechanical properties. 展开更多
关键词 Inconel 718 Laser powder bed fusion Heat treatment Strengthening mechanism Deformation behavior
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