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Real-time UAV path planning based on LSTM network

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Journal of Systems Engineering and Electronics 2024年第2期35卷 374-385页

作者： ZHANG Jiandong GUO Yukun ZHENG Lihui YANG Qiming SHI Guoqing wu yong School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China The Flight Automatic Control Research Institute of AVIC Xi’an 710065China Military Representative Office of Marine wuhan Bureau in Luoyang Area Luoyang 471000China

To address the shortcomings of single-step decision making in the existing deep reinforcement learning based unmanned aerial vehicle(UAV)real-time path planning problem,a real-time UAV path planning algorithm based on long shortterm memory(RPP-LSTM)network is proposed,which combines the memory characteristics of recurrent neural network(RNN)and the deep reinforcement learning *** networks are used in this algorithm as Q-value networks for the deep Q network(DQN)algorithm,which makes the decision of the Q-value network has some *** to LSTM network,the Q-value network can use the previous environmental information and action information which effectively avoids the problem of single-step decision considering only the current ***,the algorithm proposes a hierarchical reward and punishment function for the specific problem of UAV real-time path planning,so that the UAV can more reasonably perform path *** verification shows that compared with the traditional feed-forward neural network(FNN)based UAV autonomous path planning algorithm,the RPP-LSTM proposed in this paper can adapt to more complex environments and has significantly improved robustness and accuracy when performing UAV real-time path planning.

关键词： deep Q network path planning neural network unmanned aerial vehicle(UAV) long short-term memory(LSTM)

Simulation study on cuttings transport of the backreaming operation for long horizontal section wells

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Petroleum Science 2024年第2期21卷 1149-1170页

作者： Yu-Fei Chen Hui Zhang Wen-Xin wu Jun Li yong Ouyang Zong-Yu Lu De-Xin Ma yong-Chuan wu Jun-Bo Liu Ke-Rou Liu Zhuo-Xin Dong China University of Petroleum(Beijing) Beijing102249China Beijing Normal University at Zhuhai Experimental and Practical Education Innovation CenterZhuhai519087GuangdongChina Oil&Gas Technology Research Institute of PetroChina Changqing Oilfield Company Xi'an710016ShaanxiChina PetroChina Xinjiang Oilfield Company Karamay834002XinjiangChina China Oilfield Services Ltd. Tianjin300459China

The backreaming operation plays a significant role in safe drilling for horizontal wellbores, while it may cause severe stuck pipe accidents. To lower the risk of the stuck pipe in backreaming operations, the mechanism of cuttings transport needs to be carefully investigated. In this research, a transient cuttings transport with multiple flow patterns model is developed to predict the evolution of cuttings transported in the annulus while backreaming. The established model can provide predictions of the distribution of cuttings bed along the wellbore considering the bulldozer effect caused by large-size drilling tools(LSDTs). The sensitivity analyses of the size of LSDTs, and backreaming operating parameters are conducted in Section 4. And a new theory is proposed to explain the mechanism of cuttings transport in the backreaming operation, in which both the bit and LSDTs have the “cleaning effect” and “plugging effect”.The results demonstrate that the cuttings bed in annuli is in a state of dynamic equilibrium, but the overall trend and the distribution pattern are obvious. First, larger diameters and longer drilling tools could lead to a higher risk of the stuck pipe. Second, we find that it is not the case that the higher flow rate is always better for hole cleaning, so three flow-rate intervals are discussed separately under the given conditions. When the “dangerous flow rate”(35 L/s in Case 4),the higher the flow rate, the better the cleaning effect of cuttings beds. Third, an interval of tripping velocity called “dangerous velocity” is proposed, in which the cuttings bed accumulation near the LSDTs is more serious than

关键词： Backreaming Stuck pipe Hole cleaning Transient solid transport Multiple flow patterns

Loyal wingman task execution for future aerial combat:A hierarchical prior-based reinforcement learning approach

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Chinese Journal of Aeronautics 2024年第5期37卷 462-481页

作者： Jiandong ZHANG Dinghan WANG Qiming YANG Zhuoyong SHI Longmeng JI Guoqing SHI yong wu School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China

In modern Beyond-Visual-Range(BVR)aerial combat,unmanned loyal wingmen are pivotal,yet their autonomous capabilities are *** study introduces an advanced control algorithm based on hierarchical reinforcement learning to enhance these capabilities for critical missions like target search,positioning,and relay *** on a dual-layer model,the algorithm’s lower layer manages basic aircraft maneuvers for optimal flight,while the upper layer processes battlefield dynamics,issuing precise navigational *** approach enables accurate navigation and effective reconnaissance for lead ***,our Hierarchical Prior-augmented Proximal Policy Optimization(HPE-PPO)algorithm employs a prior-based training,prior-free execution method,accelerating target positioning training and ensuring robust target *** paper also improves missile relay guidance and promotes the effective *** integrating this system with a human-piloted lead aircraft,this paper proposes a potent solution for cooperative aerial *** experiments demonstrate enhanced survivability and efficiency of loyal wingmen,marking a significant contribution to Unmanned Aerial Vehicles(UAV)formation control *** advancement is poised to drive substantial interest and progress in the related technological fields.

关键词： Beyond-visual-range Loyal wingmen Hierarchical prior-augmented proximal policy optimization Unmanned aerial vehicles Warfare

Metastatic clear cell sarcoma of the pancreas:A rare case report

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World Journal of Clinical Cases 2024年第8期12卷 1448-1453页

作者： Yu-Jing Liu Chen Zou yong-You wu General Surgery II Suzhou HospitalThe Affiliated Hospital of Medical SchoolNanjing UniversitySuzhou 215000Jiangsu ProvinceChina Department of General Surgery The Affiliated People's Hospital of Jiangsu UniversitySuzhou 215000Jiangsu ProvinceChina Department of Gastrointestinal Surgery The Second Affiliated Hospital of Soochow UniversitySuzhou 215008Jiangsu ProvinceChina

BACKGROUND Clear cell sarcoma(CCS)is a rare soft-tissue *** most common metastatic sites for CCS are the lungs,bones and *** is highly invasive and mainly metastasizes to the lung,followed by the bone and brain;however,pancreatic metastasis is relatively *** SUMMARY We report on a rare case of CCS with pancreatic metastasis in a 47-year-old *** patient had a relevant medical history 3 years ago,with abdominal pain as the main clinical *** abnormalities were observed on physical examination and the tumor was found on abdominal computed *** on the medical history and postoperative pathology,the patient was diagnosed with CCS with pancreatic *** patient was successfully treated with surgical interventions,including distal pancreatectomy and *** This report summarizes the available treatment modalities for CCS and the importance of regular postoperative follow-up for patients with CCS.

关键词： Clear cell sarcoma Pancreas Metastasis Follow-up Case report

Ionization Potential Depression Model for Warm/Hot and Dense Plasmas

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Chinese Physics Letters 2024年第8期41卷 45-57页

作者： Chensheng wu Fuyang Zhou Jun Yan Xiang Gao yong wu Chunhua Zeng Jianguo Wang Institute of Applied Physics and Computational Mathematics Beijing 100088China Faculty of Science Kunming University of Science and TechnologyKunming 650500China

For warm/hot and dense plasmas(WDPs),ionization potential depression(IPD)plays a crucial role in determining its ionization balance and understanding the resultant microscopic plasma properties.A sophisticated and unified IPD model is necessary to resolve those existing discrepancies between theoretical and experimental ***,the applicability of those widely used IPD models nowadays is limited,especially for the nonlocal thermodynamic equilibrium(non-LTE)dense plasma produced by short-pulse *** this work,we propose an IPD model that considers inelastic atomic processes,in which three-body recombination and collision ionization processes are found to play a crucial role in determining the electron distribution and IPD for a *** IPD model is validated by reproducing latest experimental results of Al plasmas with a wide-range condition of 70 eV–700 eV temperature and 0.2–3 times solid density,as well as a typical non-LTE system of hollow Al *** is demonstrated that the present IPD model has a significant temperature dependence due to the consideration of the inelastic collision *** a lower computational cost and wider application range of plasma conditions,the proposed model is expected to provide a promising tool to study the ionization balance and the atomic processes,as well as the related radiation and particle transports properties of the WDP.

关键词： properties. collision determining

The Role of Renewable Protocatechol Acid in Epoxy Coating Modification: Significantly Improved Antibacterial and Adhesive Properties

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Chinese Journal of Polymer Science 2024年第1期42卷 63-72,I0008页

作者： Ming-Xuan Chen Jin-Yue Dai Li-Yue Zhang Shuai-Peng Wang Jing-Kai Liu yong-Gang wu Xin-wu Ba Xiao-Qing Liu School of Chemistry and Materials Science Hebei UniversityBaoding 071000China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Marine Materials and Related Technologies Chinese Academy of SciencesNingbo 315201China

It is of great significance to design epoxy coatings with superior antibacterial properties and high adhesive properties, as well as excellent processing, superior durability, and high transparency. However, it is still a challenge because of the common complex design and synthesis. Herein, the bio-based monomer protocatechuic acid(PCA) was used as raw material, the catechol structure with high bonding and antibacterial properties was introduced into the flexible alkane segment of ethylene glycol diglycidyl ether(EGDE) through an efficient, and green method, and it was cured with isophorone diamine(IPDA) to prepare corresponding thermosets. The cured resins exhibited excellent allaround qualities, particularly in bonding and antibacterial. When 30% PCA was added to pure epoxy resin, the adhesion between substrate and coating increased from 4.40 MPa to 13.60 MPa and the antibacterial rate of coating against E. coli and S. aureus could approach 100%. All of this is due to the fact that the catechol structure present in PCA has the ability to interact with various substrates and alter the permeability of bacterial cell membranes. The architecture of this method offers a fresh approach to dealing with the issues of challenging raw material selection and complex synthesis techniques.

关键词： Epoxy coatings Thermosets Catechol structure Antibacterial High adhesion

Diagnosis of poorly differentiated adenocarcinoma of the stomach by confocal laser endomicroscopy:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1481-1486页

作者： Jia-Xin Lou yong wu Muren Huhe Jing-Jie Zhang Dong-wu Jia Zhen-Yu Jiang Department of Gastroenterology The Second Affiliated Hospital of Baotou Medical CollegeInner Mongolia University of Science and TechnologyBaotou 014030Inner Mongolia Autonomous RegionChina Medical Innovation Center The Fourth Military Medical UniversityXi'an 710000Shaanxi ProvinceChina

BACKGROUND In recent years,confocal laser endomicroscopy(CLE)has become a new endoscopic imaging technology at the microscopic level,which is extensively performed for real-time in vivo histological *** can be performed to distinguish benign from malignant *** this study,we diagnosed using CLE an asymptomatic patient with poorly differentiated gastric *** SUMMARY A 63-year-old woman was diagnosed with gastric mucosal lesions,which may be gastric cancer,in the small curvature of the stomach by *** consented to undergo CLE for morphological observation of the gastric *** the combination of CLE diagnosis and postoperative pathology,the intraoperative CLE diagnosis was considered to be *** to our experience,CLE can be performed as the first choice for the diagnosis of gastric *** CLE has several advantages over pathological *** believe that CLE has great potential in the diagnosis of benign and malignant gastric lesions.

关键词： Confocal laser endomicroscopy Poorly differentiated gastric adenocarcinoma Diagnosis Early stage Case report

Auxiliary ball milling to prepare WS_(2)/graphene nanosheets composite for lithium-ion battery anode materials

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Tungsten 2024年第1期6卷 124-133页

作者： yong-Lin wu Jia-Bin Hong Wei-Xu Zhong Chun-Xiang Wang Zhi-Feng Li Sydorov Dmytro Jiangxi Provincial Key Laboratory of Power Batteries and Materials Jiangxi University of Science and TechnologyGanzhou 341000China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Institute of Bioorganic Chemistry and Petrochemistry National Academy of Sciences of UkraineKiev 02160Ukraine

A novel nano-WS_(2)/graphene nanosheets(GNSs)composite is obtained by ball milling with xylitol as auxiliary agent and hightemperature *** improves the shear force during ball milling and well overcomes the van der Waals interactions between the interlayer of graphite and WS_(2).Through high-temperature calcination,GNSs and WS_(2) nanosheets can form tight interface *** produced WS_(2)/GNSs composites can be used as anode materials for lithium-ion batteries,while maintaining a high reversible specific capacity of 705 mAh·g^(-1)with the capacity retention of 95%at a current density of 250 mA·g^(-1)after 200 cycles,mainly because WS_(2)/GNSs composites have a higher Li^(+)diffusion coefficient of 2.2×10^(-9)cm^(2)·s^(-1)and a higher specific surface area of 70.10 m^(2)·g^(-1).As a result,the xylitol-assisted ball milling method designed in this work is suitable for extended preparation of peeling of two-dimensional layer materials into nanosheets.

关键词： Lithium-ion battery Anode material WS_(2) Graphene nanosheets Auxiliary ball milling

Diagnostic performance of intravascular ultrasound-based fractional flow reserve in evaluating of intermediate left main stenosis

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Journal of Geriatric Cardiology 2024年第1期21卷 34-43页

作者： yong-Gang SUI Cheng YANG Chang-Dong GUAN Yan-Lu XU Na-Qiong wu Wei-Xian YANG yong-Jian wu Ke-Fei DOU Yue-Jin YANG Shu-Bin QIAO Wei YU Bo XU Sheng-Xian TU Jie QIAN Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Catheterization Laboratories Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Biomedical Instrument Institute School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina National Clinical Research Center for Cardiovascular Diseases BeijingChina

BACKGROUND The recently introduced ultrasonic flow ratio(UFR),is a novel fast computational method to derive fractional flow reserve(FFR)from intravascular ultrasound(IVUS)*** the present study,we evaluate the diagnostic performance of UFR in patients with intermediate left main(LM)*** This is a prospective,single center study enrolling consecutive patients with presence of intermediated LM lesions(diameter stenosis of 30%-80%by visual estimation)underwent IVUS and FFR *** independent core laboratory assessed offline UFR and IVUS-derived minimal lumen area(MLA)in a blinded *** Both UFR and FFR were successfully achieved in 41 LM patients(mean age,62.0±9.9 years,46.3%diabetes).An acceptable correlation between UFR and FFR was identified(r=0.688,P50%(AUC=0.66,P<0.001)and numerically higher than IVUS-derived MLA(AUC=0.82;P=0.09).Patient level diagnostic accuracy,sensitivity and specificity for UFR to identify FFR≤0.80 was 82.9%(95%CI:70.2-95.7),93.1%(95%CI:82.2-100.0),58.3%(95%CI:26.3-90.4),*** In patients with intermediate LM diseases,UFR was proved to be associated with acceptable correlation and high accuracy with pressure wire-based FFR as standard *** present study supports the use of UFR for functional evaluation of intermediate LM stenosis.

关键词： stenosis flow fractional