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Two-layer autonomous intelligence dynamic trajectory planning method based on shield-tunnel ring-geology interactions

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Underground space 2024年第6期19卷 227-250页

作者： min Hu Bingjian Wu Huiming Wu Liefeng pei sILC Business school Shanghai UniversityShanghai 201800China sHU-sUCG Research Centre for Building Industrialization Shanghai 201800China shanghai Tunnel Engineering Co. Ltd.Shanghai 200032China

To solve the problem that current attitude planning methods do not fully consider the interaction and constraints among the shield,segmental tunnel ring,and geology,and cannot adapt to the changes in the actual engineering environment,or provide feasible long-term and short-term attitude planning,this paper proposes autonomous intelligent dynamic trajectory planning(AI-DTP)to provide tunnel ring and centimeter-layer planning targets for a self-driving shield to meet long-term accuracy and short-term ***-DTP introduces the Frenet coordinate system to solve the problem of inconsistent spatial representation of tunnel data,segmental tunnel ring location,and surrounding geological conditions,designs the long short-term memory attitude prediction model to accurately predict shield attitude change trend based on shield,tunnel,and geology,and uses a heuristic algorithm for trajectory ***-DTP provides ring-layer and centimeter-layer planning objectives that meet the needs of long-term accuracy and short-term correction of shield attitude *** the Hangzhou-s.aoxing Intercity Railroad Tunnel Project in China,the‘‘Zhiyu”shield equipped with the AI-DTP system was faster and more accurate than the manually controlled shield,with a smoother process and better quality of the completed tunnel.

关键词： shield tunnel Trajectory planning Attitude control self-driving Machine learning

Analysis of sensitivity to hydrate blockage risk in natural gas gathering pipeline

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Petroleum science 2024年第4期21卷 2723-2733页

作者： ao-Yang Zhang Meng Cai Na Wei Hai-Tao Li Chao Zhang Jun pei Xin-Wei Wang state Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Research Institute of Production Engineering Daqing Oilfield Co.Ltd.

During the operational process of natural gas gathering and transmission pipelines, the formation of hydrates is highly probable, leading to uncontrolled movement and aggregation of hydrates. The continuous migration and accumulation of hydrates further contribute to the obstruction of natural gas pipelines, resulting in production reduction, shutdowns, and pressure build-ups. Consequently, a cascade of risks is prone to occur. To address this issue, this study focuses on the operational process of natural gas gathering and transmission pipelines, where a comprehensive framework is established. This framework includes theoretical models for pipeline temperature distribution, pipeline pressure distribution, multiphase flow within the pipeline, hydrate blockage, and numerical solution methods. By analyzing the influence of inlet temperature, inlet pressure, and terminal pressure on hydrate formation within the pipeline, the sensitivity patterns of hydrate blockage risks are derived. The research indicates that reducing inlet pressure and terminal pressure could lead to a decreased maximum hydrate formation rate, potentially mitigating pipeline blockage during natural gas transportation. Furthermore, an increase in inlet temperature and terminal pressure, and a decrease in inlet pressure, results in a displacement of the most probable location for hydrate blockage towards the terminal station. However,it is crucial to note that operating under low-pressure conditions significantly elevates energy consumption within the gathering system, contradicting the operational goal of energy efficiency and reduction of energy consumption. Consequently, for high-pressure gathering pipelines, measures such as raising the inlet temperature or employing inhibitors, electrical heat tracing, and thermal insulation should be adopted to prevent hydrate formation during natural gas transportation. Moreover, considering abnormal conditions such as gas well production and pipeline network s

关键词： Natural gas hydrates Gathering pipeline Temperature variation Hydrate formation rate sensitivity analysis

Protective effects of baffles with different positions,row spacings,heights on debris flow impact

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Journal of Mountain science 2024年第7期21卷 2352-2367页

作者： sUN Xinpo CHEN min BI Yuzhang ZHENG Lu CHE Chi XU ao TIAN Zijian JIANG Zheyuan College of Civil Engineering Sichuan University of Science and EngineeringZigong 643000China College of Resources and Environment Fujian Agriculture and Forestry UniversityFuzhou 350002China school of Civil Engineering Fuzhou UniversityFuzhou 350108China Jiangsu Key Laboratory of Urban Underground Engineering&Environmental safety Institute of Geotechnical EngineeringSoutheast UniversityNanjing 210096China Beijing Urban Construction science Technology Promoting Association Beijing 100055China sUsE-BZ Geoenvironmental Engineering Joint Laboratory Sichuan University of Science and EngineeringZigong 643000China

The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow ***,they are widely used for protection against natural hazards such as landslides and *** study,based on the threedimensional DEM(Discrete Element Method),investigated the impact of different baffle positions on debris flow *** flow velocity and kinetic energy variations were studied through single-factor *** baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris ***,based on the selected baffle positions and four factors influencing the effectiveness of baffle protection(baffle position(P),baffle height(h),row spacing(s_(r)),and angle of transit area(α)),an orthogonal design was employed to further explore the optimal arrangement of *** research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their *** the baffle is placed in the transit area,the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition ***,when the baffle is placed in the transit area,the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition *** orthogonal experimental range analysis,when the impact on the first row of baffles is used as the evaluation criterion,the importance of each influencing factor is ranked asα>P>s_(r)>*** the mass of debris flow behind the baffle is regarded as the evaluation criterion,the rank is changed to P>α>s_(r)>*** experimental simulation results show that the optimal baffle arrangement is:P_(5),s_(r)=16,α=35°,h=9.

关键词： Debris flow Baffle Protective effect Discrete element

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Very short-Term Forecasting of Distributed PV Power Using GsTANN

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CsEE Journal of Power and Energy systems 2024年第4期10卷 1491-1501页

作者： Tiechui Yao Jue Wang Yangang Wang pei Zhang Haizhou Cao Xuebin Chi min shi Computer Network Information Center of the Chinese Academy of sciences Beijing 100190China University of Chinese Academy of sciences Beijing 100190China school of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China state Grid Hebei Electric Power Co. Ltd.Shijiazhuang 050000China

Photovoltaic(PV)power forecasting is essential for secure operation of a power *** prediction of PV power can improve new energy consumption capacity,help power system planning,promote development of smart grids,and ultimately support construction of smart energy ***,different from centralized PV power forecasts,three critical challenges are encountered in distributed PV power forecasting:1)lack of on-site meteorological observation,2)leveraging extraneous data to enhance forecasting performance,3)spatial-temporal modelling methods of meteorological information around the distributed PV *** address these issues,we propose a Graph spatial-Temporal Attention Neural Network(GsTANN)to predict the very short-term power of distributed ***,we use satellite remote sensing data covering a specific geographical area to supplement meteorological information for all PV ***,we apply the graph convolution block to model the non-Euclidean local and global spatial dependence and design an attention mechanism to simultaneously derive temporal and spatial ***,we propose a data fusion module to solve the time misalignment between satellite remote sensing data and surrounding measured on-site data and design a power approximation block to map the conversion from solar irradiance to PV *** conducted with real-world case study datasets demonstrate that the prediction performance of GsTANN outperforms five state-of-the-art baselines.

关键词： Distributed photovoltaic power forecasting graph convolutional networks satellite images spatial-temporal attention

Impact of propofol and sevoflurane anesthesia on cognition and emotion in gastric cancer patients undergoing radical resection

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 79-89页

作者： ao-Han Li su Bu Ling Wang Ai-min Liang Hui-Yu Luo Department of Anesthesiology Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Cardiothoracic surgery Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Rehabilitation Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Internal Medicine-Cardiovascular Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina

BACKGROUND Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric ***,there is a debate concerning their differential effects on cognitive function,anxiety,and depression in patients undergoing this *** To compare the effects of propofol and sevoflurane anesthesia on postoperative cognitive function,anxiety,depression,and organ function in patients undergoing radical resection of gastric *** A total of 80 patients were involved in this *** subjects were divided into two groups:Propofol group and sevoflurane *** evaluation scale for cognitive function was the Loewenstein occupational therapy cognitive assessment(LOTCA),and anxiety and depression were assessed with the aid of the self-rating anxiety scale(sAs)and self-rating depression scale(sDs).Hemodynamic indicators,oxidative stress levels,and pulmonary function were also *** The LOTCA score at 1 d after surgery was significantly lower in the propofol group than in the sevoflurane ***,the sAs and sDs scores of the sevoflurane group were significantly lower than those of the propofol *** sevoflurane group showed greater stability in heart rate as well as the mean arterial pressure compared to the propofol ***,the sevoflurane group displayed better pulmonary function and less lung injury than the propofol *** Both propofol and sevoflurane could be utilized as maintenance anesthesia during radical resection of gastric *** anesthesia has a minimal effect on patients'pulmonary function,consequently enhancing their postoperative *** anesthesia causes less impairment on patients'cognitive function and mitigates negative emotions,leading to an improved postoperative mental ***,the selection of anesthetic agents should be based on the individual patient's specific circumstances.

关键词： Propofol sevoflurane Radical resection of gastric cancer Anesthetic effect Cognitive function Negative emotion

The centrosymmetric to non-centrosymmetric transformation induced by alkaline-earth cations producing infrared nonlinear optical AeMn_(6)Ga_(6)s_(16)(Ae=Ca,sr)

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science China Chemistry 2024年第9期67卷 2941-2948页

作者： Yang-Ping Zhang s.ao-min pei Wen-Fa Chen Bin-Wen Liu Xiao-ming Jiang Guo-Cong Guo state Key Laboratory of structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China school of Physical science and Technology Shanghai Tech UniversityShanghai 201210China

Non-centrosymmetric(NCs)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)***,the mainstream approach for designing new NCs structures still relies on chemical substitution,necessitating an urgent infusion of fresh *** this work,two isomorphic sulfides AeMn_(6)Ga_(6)s_(16)(Ae=Ca,1;sr,2)are afforded by modifying the skeleton of centrosymmetric(Cs)Mn_(2)Ga_(2)s_(5) via introducing strong electropositive alkaline-earth ***,the incorporation of Ca^(2+)/sr^(2+)cations allows the elementary[MnGas_(9)]_(∞)chains to reconfigure into bumpy[Mns_(6)]-[Gas_(4)]layers in a new engagement manner,thus enabling the conversion from Cs to NCs *** modifications cause not only strong second-harmonic generation(sHG)responses(~1.5×benchmark AgGas_(2)@1,700 nm),but also significantly feasible bandgaps(2.60-2.64 e V)compared to the sulfide Mn_(2)Ga_(2)s_(5)(1.36 e V),which ultimately facilitate ultrahigh laser-induced damage thresholds(4.4-6.6×AgGas_(2)@1,064 nm for compounds 1 and 2).The present study offers an ingenious approach for the transformation of Cs to NCs structure.

关键词： second-harmonic generation non-centrosymmetrical structure NLO functional motif solid-state method

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FAM53B promotes pancreatic ductal adenocarcinoma metastasis by regulating macrophage M2 polarization

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1479-1499页

作者： Xuan-Zeng pei min Cai Da-Wei Jiang song-Hai Chen Qing-Qing Wang Hui-min Lu Yi-Fan Lu Department of Hepatological surgery The First Hospital of JiaxingJiaxing 314000Zhejiang ProvinceChina Department of General surgery West China Hospital of Sichuan UniversityChengdu 610044Sichuan ProvinceChina

BACKGROUND Our study investigated the role of FAM53B in regulating macrophage M2 polarization and its potential mechanisms in promoting pancreatic ductal adenocarcinoma(PDAC)*** To further investigate the role of FAM53B in regulating macrophage M2 polarization and its potential mechanism in promoting PDAC *** goal is to determine how FAM53B affects macrophage M2 polarization and to define its underlying mechanism in PDAC *** Cell culture and various experiments,including protein analysis,immunohisto-chemistry,and animal model experiments,were *** compared FAM53B expression between PDAC tissues and healthy tissues and assessed the correlation of FAM53B expression with clinical *** study analyzed the role of FAM53B in macrophage M2 polarization in vitro by examining the expression of relevant ***,we used a murine model to study the role of FAM53B in PDAC metastasis and analyzed the potential underlying *** Our research showed that there was a significant increase in FAM53B levels in PDAC tissues,which was linked to adverse tumor *** findings indicated that FAM53B can enhance macrophage M2 polarization,leading to increased anti-inflammatory factor *** results from the mouse model further supported the role of FAM53B in PDAC metastasis,as blocking FAM53B prevented tumor cell invasion and *** FAM53B promotes PDAC metastasis by regulating macrophage M2 *** discovery could lead to the development of new strategies for treating *** example,interfering with the FAM53B signaling pathway may prevent cancer *** research findings also provide important information for expanding our understanding of PDAC pathogenesis.

关键词： FAM53B Pancreatic ductal adenocarcinoma Tumor metastasis Macrophage polarization

Perioperative and long-term results of ultrasonography-guided single-and multiple-tract percutaneous nephrolithotomy for staghorn calculi

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World Journal of Clinical Cases 2024年第7期12卷 1243-1250页

作者： Rui-Xiang Cheng Ni Dai Yan-min Wang pei Qi Fen Chen Department of Urology Wuhan Ninth HospitalWuhan 430081Hubei ProvinceChina Department of Urinary Pain Wuhan Hankou HospitalWuhan 430000Hubei ProvinceChina Pre-hospital Emergency Department Wuhan Puren HospitalWuhan 430081Hubei ProvinceChina Department of Orthopedic Trauma surgery Wuhan Hankou HospitalWuhan 430000Hubei ProvinceChina Department of Ultrasound Hubei Provincial Hospital of Integrated Traditional Chinese and Western MedicineWuhan 430015Hubei ProvinceChina

BACKGROUND It is possible that this condition will lead to urosepsis and progressive deterioration of renal function in the absence of surgical *** recent clinical studies have shown that multi-tract percutaneous nephrolithotomy(MPCNL)has a similar stone free rate(sFR)as standard percutaneous nephrolithotomy(s-PCNL).As a result,M-PCNL was also recommended as a treatment option for staghorn *** To examine the perioperative and long-term results of ultrasonography-guided single-and *** This was a retrospective cohort *** March 2021 and January 2022,the urology department of our hospital selected patients for the treatment of staghorn calculi using percutaneous *** primary outcomes were com plication rate and sFR,and the characteristics of patients,operative parameters,laboratory measurements were also *** In total,345 patients were enrolled in the study(186 in the s-PCNL group and 159 in the M-PCNL group).The sFR in the M-PCNL group was significantly higher than that in the s-PCNL group(P=0.033).Moreover,the incidence rates of hydrothorax(P=0.03)and postoperative infection(P=0.012)were higher in the M-PCNL group than in the s-PCNL *** regression analysis demonstrated that post-operative white blood cell count(OR=2.57,95%CI:1.90-3.47,Pstone size(OR=1.59,95%CI:1.27-2.00,Pssociated with a higher overall complication rate in the s-PCNL *** mass index(OR=1.22,95%CI:1.06-1.40,P=0.004)and stone size(OR=1.70,95%CI:1.35-2.15,Pssociated with increased overall complications in the M-PCNL *** Multiple access tracts can facilitate higher sFR while slightly increasing the incidence of acceptable complications.

关键词： single-tract percutaneous nephrolithotomy Multiple-tract percutaneous nephrolithotomy staghorn calculi Ultrasonography

Flexible bidirectional self-powered photodetector with significantly reduced volume and accelerated response speed based on hydrogel and lift-off GaN-based nanowires

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Fundamental Research 2024年第2期4卷 369-378页

作者： min Jiang Yukun Zhao Penghui Zheng Jianya Zhang Wenxian Yang min Zhou Yuanyuan Wu Renjun pei shulong Lu Key Lab of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of Sciences(CAS)Suzhou 215123China school of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China CAs Key Laboratory of Nano-Bio Interface Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Nanchang Research Institute Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesNanchang 330200China

Due to the wide range of potential applications for next-generation multi-functional devices,the flexible selfpowered photodetector(PD)with polarity-switchable behavior is essential but very challenging to be ***,a wearable bidirectional self-powered PD based on detached(Al,Ga)N and(In,Ga)N nanowires has been proposed and demonstrated *** from the photovoltage-competing dynamics across(Al,Ga)N and(In,Ga)N nanowire photoelectrodes,such PD can generate the positive(33.3 mA W−1)and negative(-0.019 mA W−1)photo-responsivity under ultraviolet(UV)and visible illumination,respectively,leading to the bidirectional photocurrent *** to the introduction of quasi solid-state hydrogel,the PD can work without the liquid-electrolyte,thus remarkably reducing the volume from about 482 cm3 to only 0.18 ***,the use of hydrogel is found to enhance response speed in the UV range by reducing the response time for more than 95%,which is mainly attributed to the increased open circuit potential and reduced ion transport *** the GaN connecting segment is pretty thin,the piezoelectric charges generated by stress are proposed to have only a limited effect on the photocurrent ***,both the stable on-off switching characteristics and photocurrent densities can still be achieved after being bent 400 *** an excellent flexibility,this work creates opportunities for technological applications of bidirectional photocurrent PDs in flexible optoelectronic devices,e.g.,wearable intelligent sensors.

关键词： Flexible photodetector Bidirectional photocurrent Lift-off GaN-based nanowires Hydrogel self-powered device