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Aerial refueling scheduling of multi-receiver and multi-tanker under spatial-temporal constraints for forest firefighting

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Chinese Journal of Aeronautics 2024年第5期37卷 71-91,I0001页

作者： Jing HUANG Jiaqi xing Jinrui REN quan quan Youmin ZHANG Department of Information and Control Engineering Xi’an University of TechnologyXi’an 710048China Jiujiang Measuring Test Technology Research Institute Jiujiang 332000China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China School of Automation Xi’an University of Posts&TelecommunicationsShaanxiXi’an 710121China Department of Mechanical Industrial and Aerospace EngineeringConcordia UniversityMontreal H3G 1M8Canada

Forest fires pose a significant threat to human life and property,so the utilization of unmanned aircraft systems provides new ways for forest *** the constrained load capacities of these aircraft,aerial refueling becomes crucial to extend their operational time and *** order to address the complexities of firefighting missions involving multi-receiver and multi-tanker deployed from various airports,first,a fuel consumption calculation model for aerial refueling scheduling is established based on the receiver ***,two distinct methods,including an integrated one and a decomposed one,are designed to address the challenges of establishing refueling airspace and allocating tasks for *** methods aim to optimize total fuel consumption of the receivers and tankers within the aerial refueling scheduling *** optimization problem is established as nonlinear optimization models along with *** integrated method seamlessly combines refueling rendezvous point scheduling and tanker task allocation into unified *** has a complete solution space and excels in optimizing total fuel *** decomposed method,through the separation of rendezvous point scheduling and task allocation,achieves a reduced computational ***,this comes at the cost of sacrificing optimality by excluding specific feasible ***,numerical simulations are carried out to verify the feasibility and effectiveness of the proposed *** simulations yield insights crucial for the practical engineering application of both the integrated and decomposed methods in real-world *** comprehensive approach aims to enhance the efficiency of forest firefighting operations,mitigating the risks posed by forest fires to human life and property.

关键词： Aerial refueling Scheduling Planning Spatial-temporal constraint Firefighting

电感耦合等离子体原子发射光谱法同时测定工业氯化钙中的钠镁和铁

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广州化工 2024年第2期52卷 150-152,169页

作者：赵枝刚王兴权程金莲张淑琴王微芝海西州盐化工产品质量检验检测中心青海格尔木816099 青海理工大学青海西宁810000

工业氯化钙经硝酸消解定容后,采用电感耦合等离子体发射光谱法同时测定工业氯化钙中钠、镁和铁含量,经过系数换算可以得出碱金属氯化物、总镁及铁含量。对样品分析谱线选择进行了研究,在钠589.592 nm、镁279.553 nm、铁选用259.940 nm... 详细信息

工业氯化钙经硝酸消解定容后,采用电感耦合等离子体发射光谱法同时测定工业氯化钙中钠、镁和铁含量,经过系数换算可以得出碱金属氯化物、总镁及铁含量。对样品分析谱线选择进行了研究,在钠589.592 nm、镁279.553 nm、铁选用259.940 nm波长下,碱金属氯化物检出限为0.0008%,7次测定最大极差为0.17%;总镁检出限为0.00008%,7次测定最大极差为0.0013%;铁检出限为0.000003%,7次测定最大极差为0.00011%,三种组分的加标回收率在90%~110%之间,本方法测定值与仲裁法测定值最大极差满足仲裁法允许差要求,具有较高的准确性和可靠性,该方法与仲裁法相比,具有前处理简单、试剂消耗少、人为主观因素影响小,平行样允许差小,测量结果精度高等特点,实现一种方法代替多种方法同时测定碱金属氯化物、总镁、铁含量,该方法易操作,能满足大批量工业氯化钙中碱金属氯化物、总镁和铁含量的同时测定。

关键词：工业氯化钙电感耦合等离子体原子发射光谱法碱金属氯化物总镁铁

Mechanical Performances of Carbonitriding Films on Cast Iron by Plasma Electrolytic Carbonitriding

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Chinese Physics Letters 2011年第11期28卷 243-245页

作者： PANG Hua ZHANG Gu-Ling wang xing-quan LV Guo-Hua CHEN Huan YANG Si-Ze Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190 Fujian Key Laboratory for Plasma and Magnetic Resonance Department of AeronauticsSchool of Physics and Mechanical and Electrical EngineeringXiamen UniversityXiamen 361005 College of Science Minzu University of ChinaBeijing 100081

The plasma electrolytic carbonitriding(PEC/N)process is applied to cast iron using an aqueous solution of acetamide and glycerin as the *** properties of the carbonitriding layers on cast iron are *** the PEC/N treatment,the microhardness and wear resistance of cast iron are improved significantly compared to the untreated *** the substrate is processed at 350V for 60 s,the coating presents the highest microhardness and it is about 554.14HK0.02,and the coating with the highest hardness has the best wear resistance.

关键词： nitriding wear coating

Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

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Biomedical and Environmental Sciences 2024年第2期37卷 196-203页

作者： wang Dan Dan wang An Xin ZHANG Xiao Li WEI Wen Bin WU Shou Ling ZHAO xing quan Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China China National Clinical Research Center for Neurological Diseases Beijing 100070China Beijing Tongren Eye Center Beijing Key Laboratory of Ophthalmology and Visual ScienceBeijing Tongren HospitalCapital Medical UniversityBeijing 100005China Department of Cardiology Kailuan HospitalTangshan 063001HebeiChina

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population *** study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular *** We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or *** regression was used to analyze the relationship between retinal metrics and cognitive *** stratified by different vascular statuses were also *** RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05).Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel *** underlying small vessel change in RNFL and CI should be investigated in the future.

关键词： Retinal nerve fiber layer Cognitive impairment Polyvascular abnormality

Reinforcement Learning-Based Dynamic Order Recommendation for On-Demand Food Delivery

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Tsinghua Science and Technology 2024年第2期29卷 356-367页

作者： xing wang Ling wang Chenxin Dong Hao Ren Ke xing Department of Automation Tsinghua UniversityBeijing 100080China School of Mechanical and Automotive Engineering Qingdao Hengxing University of Science and TechnologyQingdao 266100China Meituan Beijing 100015China

On-demand food delivery(OFD)is gaining more and more popularity in modern *** a kernel order assignment manner in OFD scenario,order recommendation directly influences the delivery efficiency of the platform and the delivery experience of *** paper addresses the dynamism of the order recommendation problem and proposes a reinforcement learning solution *** actor-critic network based on long short term memory(LSTM)unit is designed to deal with the order-grabbing conflict between different ***,three rider sequencing rules are accordingly proposed to match different time steps of the LSTM unit with different *** test the performance of the proposed method,extensive experiments are conducted based on real data from Meituan delivery *** results demonstrate that the proposed reinforcement learning based order recommendation method can significantly increase the number of grabbed orders and reduce the number of order-grabbing conflicts,resulting in better delivery efficiency and experience for the platform and riders.

关键词： on-demand food delivery order recommendation reinforcement learning actor-critic network long short term memory

A survey on facial image deblurring

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Computational Visual Media 2024年第1期10卷 3-25页

作者： Bingnan wang Fanjiang Xu quan Zheng Institute of Software Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

When a facial image is blurred,it significantly affects high-level vision tasks such as face *** purpose of facial image deblurring is to recover a clear image from a blurry input image,which can improve the recognition accuracy,***,general deblurring methods do not perform well on facial ***,some face deblurring methods have been proposed to improve performance by adding semantic or structural information as specific priors according to the characteristics of the facial *** this paper,we survey and summarize recently published methods for facial image deblurring,most of which are based on deep ***,we provide a brief introduction to the modeling of image ***,we summarize face deblurring methods into two categories:model-based methods and deep learning-based ***,we summarize the datasets,loss functions,and performance evaluation metrics commonly used in the neural network training *** show the performance of classical methods on these datasets and metrics and provide a brief discussion on the differences between model-based and learning-based ***,we discuss the current challenges and possible future research directions.

关键词： facial image deblurring model-based deep learning-based semantic or structural prior

Experimental study on temperature fluctuations on plate surface induced by coaxial-jet flow

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Nuclear Science and Techniques 2024年第5期35卷 139-153页

作者： Xue-Yao Xiong Zun-quan Liu Guo-Yan Zhou xing Luo Shan-Tung Tu Key Laboratory of Pressure Systems and Safety(MOE) East China University of Science and TechnologyShanghai 200237China Institute of Thermodynamics Gottfried Wilhelm Leibniz University Hannover30823 GarbsenGermany

In nuclear reactors,temperature fluctuations of fluids may cause fatigue damage to adjacent structures;this is referred to as thermal *** on thermal striping in the upper plenum has mainly focused on fluid *** experimental studies have been reported on solid structures in a fluid field with a coaxial *** study entailed an experimental study of the temperature fluctuations in the fluid and on a plate surface caused by a coaxial *** temperature fluctuations of the fluid and plate surfaces located at different heights were *** cause of the temperature fluctuation was analyzed using a transient temperature *** results show that the mixing of the hot and cold fluids gradually becomes uniform in the positive axial *** average surface temperatures tended to be *** the jet reaches the plate surface,the swing of the jet center,contraction and expansion of the cold jet,and changes in the jet shape result in temperature *** intensity of the temperature fluctuation was affected by the *** attention should be paid when the plate is located at a lower height,and between the hot and cold-fluid nozzles.

关键词： Temperature fluctuation Thermal striping Coaxial jet Thermal mixing The upper plenum of nuclear reactor

Strong shock propagation for the finite-source circular blast in a confined domain

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1071-1084页

作者： Qihang MA Kaileong CHONG Bofu wang quan ZHOU Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

The circular explosion wave produced by the abrupt discharge of gas from a high-temperature heat source serves as a crucial model for addressing explosion phenomena in compressible *** reflection of the primary shock and its propagation within a confined domain are studied both theoretically and numerically in this *** the assumption of strong shock,the scaling law governing propagation of the main shock is *** dimensionless frequency of reflected shock propagation is associated with the confined *** numerical simulation for the circular explosion problem in a confined domain is performed for *** the influence of confinement,the principal shock wave systematically undergoes reflection within the domain until it weakens,leading to the non-monotonic attenuation of kinetic energy in the explosion fireball and periodic oscillations of the fireball volume with a certain *** simulation results indicate that the frequency of kinetic energy attenuation and the volume oscillation of the explosive fireball align consistently with the scaling law.

关键词： explosion confinement main shock frequency

Asymptomatic low-grade appendiceal mucinous neoplasm:A case report

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World Journal of Clinical Cases 2024年第2期12卷 361-366页

作者： Min-quan Yao Yu-Peng Jiang Yuan-Yu wang Yi-Ping Mou Jin-xing Fan Department of Gastrointestinal Surgery Tongxiang First People’s HospitalJiaxing 314500Zhejiang ProvinceChina Department of General Surgery Zhejiang Provincial People’s HospitalHangzhou 310014Zhejiang ProvinceChina Endoscopy Center Tongxiang First People’s HospitalJiaxing 314500Zhejiang ProvinceChina

BACKGROUND Low-grade appendiceal neoplasms(LAMN)are characterized by low incidence and atypical clinical presentations,often leading to misdiagnosis as acute or chronic appendicitis before *** primary diagnostic tool for LAMN is abdominal computed tomography(CT)*** resection remains the cornerstone of LAMN management,necessitating en bloc tumor excision to minimize the risk of iatrogenic ***,known for its minimal invasiveness,reduced postoperative discomfort,and expedited recovery,is a safe and reliable approach for LAMN *** the possibility of pseudomyxoma peritonei development,appendectomy and partial appendectomy generally result in negative tumor margins and favorable outcomes,which can be attributed to the disease’s slow growth and lower *** SUMMARY A 71-year-old male patient was admitted to our hospital with a pelvic spaceoccupying lesion detected 1 mo *** examination showed a soft abdomen without tenderness or rebound and no palpable *** shifting dullness was noted,and digital rectal examination revealed no palpable *** revealed a raised,smooth-surfaced mass measuring 3.0 cm in the *** contrast-enhanced CT showed a markedly thickened and dilated appendix with visible cystic *** surgery was performed and revealed a significantly dilated appendix,leading to laparoscopic resection of the appendix and part of the ***-surgical pathologic analysis confirmed *** patient received symptomatic and supportive post-operative care and was discharged on postoperative day 4 without complications such as abdominal bleeding,intestinal obstruction,or incision *** tumor recurrence was observed during a 7-mo follow-up *** LAMN is a rare disease that lacks specific clinical *** CT plays a crucial role in diagnosing LAMN,and laparoscopic surgery is a safe and effective diagnostic and therapeutic approach.

关键词： Low-grade appendiceal mucinous neoplasm Pseudomyxoma peritonei Computed tomography Laparoscopy appendectomy Case report