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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1269-1276页

作者： wei-wei xiong yong zhang cheng-liang yin Institute of Automotive Engineering Shanghai Jiao Tong University Shanghai 200240 China

This paper aims to present the configuration design approach and the energy management strategy (EMS) of a series-parallel hybrid electric transit bus (SPHEB) jointly developed by Shanghai Automotive Industry Co. Ltd. (SAIC) and Shanghai Jiao Tong University (SJTU), China. A major feature of this SPHEB is that a novel manual transmission is designed to switch the powertrain configuration between series and parallel types. To reduce the fuel consumption as well as sustain the battery state of charge, an EMS including seven energy flow modes is designed and applied to this SPHEB. Governed by this EMS, the engine is maintained to operate in high efficiency regions. The experimental test carried on the transit bus city driving cycle is described and analyzed. The experimental results demonstrate the technical feasibility and fuel economy of this approach.

关键词：混合动力电动客车配置设计实验测试并联型能源管理能量管理策略环境管理体系验证

Joint UAV trajectory and communication design with heterogeneous multi-agent reinforcement learning

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Science China(Information Sciences) 2024年第3期67卷 225-245页

作者： Xuanhan ZHOU Jun xiong Haitao ZHAO Xiaoran LIU Baoquan REN Xiaochen zhang Jibo wei Hao yin College of Electronic Science and Technology National University of Defense Technology Systems Engineering Institute Academy of Military Sciences PLA

Unmanned aerial vehicles(UAVs) are recognized as effective means for delivering emergency communication services when terrestrial infrastructures are unavailable. This paper investigates a multiUAV-assisted communication system, where we jointly optimize UAVs’ trajectories, user association, and ground users(GUs)’ transmit power to maximize a defined fairness-weighted throughput metric. Owing to the dynamic nature of UAVs, this problem has to be solved in real time. However, the problem’s non-convex and combinatorial attributes pose challenges for conventional optimization-based algorithms, particularly in scenarios without central controllers. To address this issue, we propose a multi-agent deep reinforcement learning(MADRL) approach to provide distributed and online solutions. In contrast to previous MADRLbased methods considering only UAV agents, we model UAVs and GUs as heterogeneous agents sharing a common objective. Specifically, UAVs are tasked with optimizing their trajectories, while GUs are responsible for selecting a UAV for association and determining a transmit power level. To learn policies for these heterogeneous agents, we design a heterogeneous coordinated QMIX(HC-QMIX) algorithm to train local Q-networks in a centralized manner. With these well-trained local Q-networks, UAVs and GUs can make individual decisions based on their local observations. Extensive simulation results demonstrate that the proposed algorithm outperforms state-of-the-art benchmarks in terms of total throughput and system fairness.

关键词： unmanned aerial vehicle (UAV) trajectory design resource allocation multi-agent deep reinforcement learning (MADRL) heterogeneous agents

Tuning microstructures of Mg-Ce-Ni hydrogen storage alloys via Cu and carbon nanotube additions

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Nano Research 2024年第8期17卷 7203-7211页

作者： Linlin zhang liang xiong Bingyang Gao Qingyun Shi ying Wang Zhiya Han Zhenhua zhang Chunli Wang Limin Wang yong cheng State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Purification Equipment Research Institute of CSIC Handan 056002China

Mg-based alloys are regarded as highly promising materials for hydrogen *** significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics and high thermodynamic stability continue to limit their practical *** this study,to assess hydrogen storage alloys with enhanced properties,incorporating both internal microstructure modulation through the preparation of amorphous/nanocrystalline structures and surface property enhancement with the addition of Cu and carbon nanotubes(CNTs),the kinetic properties of activation and hydrogenation,thermodynamic properties,and dehydrogenation kinetics are *** results reveal a complementary interaction between the added Cu and CNTs,contributing to the superior hydrogen storage performance observed in sample 7A-2Cu-1CNTs with an amorphous/nanocrystalline structure compared to the other experimental ***,the samples are fully activated after the initial hydrogen absorption and desorption cycle,demonstrating outstanding hydrogenation kinetics under both high and low temperature experimental *** noteworthy is that the hydrogen absorption exceeds 1.8 wt.%within one hour at 333 ***,the activation energy for dehydrogenation is decreased to 64.71 kJ·mol^(–1).This research may offer novel insights for the design of new-type Mg-based hydrogen storage alloys,which possess milder conditions for hydrogen absorption and desorption.

关键词： Mg-Ni-Ce alloy hydrogen storage amorphous/nanocrystalline structure kinetics Cu and carbon nanotubes(CNTs)codoping

Clinical outcome and prognostic factors of T4N0M0 colon cancer after R0 resection:A retrospective study

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1869-1877页

作者： Bang Liu Zhao-xiong zhang Xin-Yang Nie wei-Lin Sun yong-Jia Yan wei-Hua Fu Department of General Surgery Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China

BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this *** To screen prognostic risk factors for T4N0M0 colon cancer and construct a prognostic nomogram model for these *** Two hundred patients with T4N0M0 colon cancer were treated at Tianjin Medical University General Hospital between January 2017 and December 2021,of which 112 patients were assigned to the training cohort,and the remaining 88 patients were assigned to the validation *** between the training and validation groups were *** training cohort was subjected to multi-variate analysis to select prognostic risk factors for T4N0M0 colon cancer,followed by the construction of a nomogram *** The 3-year overall survival(OS)rates were 86.2%and 74.4%for the training and validation cohorts,***(P=0.000),T stage(P=0.001),right hemicolon(P=0.025),irregular review(P=0.040),and carbohydrate antigen 199(CA199)(P=0.011)were independent risk factors of OS in patients with T4N0M0 colon cancer.A nomogram model with good concordance and accuracy was *** Enterostomy,T stage,right hemicolon,irregular review,and CA199 were independent risk factors for OS in patients with T4N0M0 colon *** nomogram model exhibited good agreement and accuracy.

关键词： T4N0M0 colon cancer Prognosis Multivariate analysis Nomogram Colon cancer

Dynamic Spacer Installation of Multifunctionalities into Metal-Organic Frameworks for Spontaneous One-Step Ethylene Purification from a Ternary C_(2)-Hydrocarbons Mixture

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CCS Chemistry 2024年第1期6卷 241-254页

作者： Yang-Yang xiong cheng-Xia Chen Tony Pham zhang-Wen wei Katherine A.Forrest Mei Pan cheng-yong Su MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275 Department of Chemistry University of South FloridaTampaFlorida 33620

Simultaneous ethane and acetylene removal from a C_(2)-gases mixture(C_(2)H_(6),C_(2)H_(4),and C_(2)H_(2))through a one-step separation process for ethylene purification is of great importance yet challenging in petrochemical industry,owing to their similar molecule sizes and physical ***,a series of multifunctionalized metal–organic frameworks(MOFs),LIFM-XYY-1∼8(LIFM stands for Lehn Institute of Functional Materials,and XYY are the initials of the first author),are constructed via a dynamic spacer installation(DSI)approach to optimize the pore-nanospaces for efficient C_(2)H_(4) isolation from the ternary C_(2)-gases *** of variable organic-spacers into the prototypical MOFs,LIFM-28 or PCN-700,results in dramatically improved pore volume/surface area,contracted pore size,and functionalized pore surface,which in turn bring out high C_(2)-gases uptake capacities,enhanced C_(2)H_(6) and C_(2)H_(2) adsorption selectivities over C_(2)H_(4),and fast adsorption kinetics,providing an effective strategy to achieve delicate trade-off among these indexes for adequate separation ***,optimized LIFM-XYY-7 presents four-times C_(2)H_(6) and C_(2)H_(2) adsorption capacities than *** breakthrough experiments reveal that poly-grade C_(2)H_(4)(>99.9%)can be obtained from binary or ternary C_(2)-hydrocarbon mixtures through a single separation *** with themolecular simulations,this work demonstrates a promising protocol of porenanospace engineering via multi-functional optimization by the DSI approach to screen out MOFs for a formidable task.

关键词： metal-organic frameworks dynamic spacer installation C_(2)H_(6)/C_(2)H_(2)/C_(2)H_(4)gases separation pore nanospace engineering multi-functional optimization

Anion-induced differential assembly and structural transformation of supramolecular coordination cages

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Chinese Chemical Letters 2024年第3期35卷 268-272页

作者： Shao-Ping Zheng Yao-wei Xu Pei-Yang Su Chen-Hui Liu yin-Hui Huang Yu-Lin Lu zhang-Wen wei Zhiwei Jiao Hai-Sen Xu cheng-yong Su MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510006China Institute of Environmental Research at Greater Bay Area Guangzhou UniversityGuangzhou 510006China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The intimate host-anion interactions will regulate thermodynamics and kinetics in the self-assembly of cationic cages mimicking biological ***,we report construction and transformation of three Pd(Ⅱ)-based metal-organic cages(MOCs)depending on different *** conversions of the lantern-shaped MOC-34 into either octahedral MOC-35 or tricapped trigonal prism MOC-36 are induced by BF_(4)^(–)or NO_(3)^(–),***-36 is kinetically favored and can undergo quantitative conversion to the thermodynamically preferred MOC-35 upon heating,accelerated by excess BF_(4)^(–)to motivate dissociative dynamics of Pd-vertices and lower activation barrier of cage *** guest encapsulation behaviors of MOC-35 and MOC-36 have also been *** results manifest a significance of host-anion dynamics beyond complementary anion template,shedding light on the understanding of intricate anion recognition in nature.

关键词： Supramolecular coordination cage Dynamic host-anion interactions Structural transformation Anion receptor Guest inclusion

Accelerating Asteroidal Period and Pole Inversion from Multiple Lightcurves Using Parallel Differential Evolution and Cellinoid Shape Model

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Research in Astronomy and Astrophysics 2024年第4期24卷 271-286页

作者： yong-xiong zhang Wen-Xiu Guo Xiao-Ping Lu Hua Zheng Hai-Bin Zhao Jun Tian wei-Lin Wang School of Engineering Guangzhou College of Technology and BusinessGuangzhou 510850China School of Computer Science and Engineering Macao University of Science and TechnologyTaipaMacao 999078China School of Mathematics and Statistics Shaoguan UniversityShaoguan 512099China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryCASNanjing 210023China

Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally *** paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution(PDE)algorithm to accelerate *** PDE algorithm is more efficient than the Differential Evolution algorithm,achieving an extraordinary speedup of 37.983 with 64 workers on multicore *** PDE algorithm accurately derives period and pole values from simulated *** analysis of real asteroid lightcurves validates the method’s reliability:in comparison with results published elsewhere,the PDE algorithm accurately recovers the rotational periods and,given adequate viewing geometries,closely matches the pole *** PDE approach converges to solutions within 20,000 iterations and under one hour,demonstrating its potential for large-scale data *** work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks.

关键词： methods:numerical minor planets asteroids:general techniques:photometric astrom

Type I critical dynamical scalarization and descalarization in Einstein-Maxwell-scalar theory

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Jia-Yan Jiang Qian Chen Yunqi Liu Yu Tian wei xiong cheng-yong zhang Bin Wang Center for Gravitation and Cosmology College of Physical Science and Technology Yangzhou University Department of Physics and Siyuan Laboratory Jinan University School of Physical Sciences University of Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences School of Physics and Optoelectronics South China University of Technology School of Aeronautics and Astronautics Shanghai Jiao Tong University

We investigated the critical dynamical scalarization and descalarization of black holes within the framework of the EinsteinMaxwell-scalar theory featuring higher-order coupling functions. Both the critical scalarization and descalarization displayed first-order phase transitions. When examining the nonlinear dynamics near the threshold, we always observed critical solutions that are linearly unstable static scalarized black holes. The critical dynamical scalarization and descalarization share certain similarities with the type I critical gravitational collapse. However, their initial configurations, critical solutions, and final outcomes differ significantly. To provide further insights into the dynamical results, we conducted a comparative analysis involving static solutions and perturbative analysis.

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TypeⅠcritical dynamical scalarization and descalarization in Einstein-Maxwell-scalar theory

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 40-58页

作者： Jia-Yan Jiang Qian Chen Yunqi Liu Yu Tian wei xiong cheng-yong zhang Bin Wang Department of Physics and Siyuan Laboratory Jinan UniversityGuangzhou 510632China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

We investigated the critical dynamical scalarization and descalarization of black holes within the framework of the EinsteinMaxwell-scalar theory featuring higher-order coupling *** the critical scalarization and descalarization displayed first-order phase *** examining the nonlinear dynamics near the threshold,we always observed critical solutions that are linearly unstable static scalarized black *** critical dynamical scalarization and descalarization share certain similarities with the typeⅠcritical gravitational ***,their initial configurations,critical solutions,and final outcomes differ *** provide further insights into the dynamical results,we conducted a comparative analysis involving static solutions and perturbative analysis.

关键词： black hole(de)scalarization dynamical critical behavior attractor

Unveiling the secrets of gastrointestinal mucous adenocarcinoma survival after surgery with artificial intelligence:A population-based study

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2404-2418页

作者： Jie Song Xiang-Xiu Yan Fang-liang zhang yong-Yi Lei Zi-yin Ke Fang Li Kai zhang Yu-Qi He wei Li Chao Li Yuan-Ming Pan Department of Gastroenterology Dongying People’s HospitalDongying Hospital of Shandong Provincial Hospital GroupDongying 257000Shandong ProvinceChina Gastrointestinal Surgery Department Suining Central HospitalSuining 629000Sichuan ProvinceChina Obstetrical Department Suining Central HospitalSuining 629000Sichuan ProvinceChina School of Medicine Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107Guangdong ProvinceChina Department of Pathology Aerospace Center HospitalPeking University Aerospace School of Clinical MedicineBeijing 100049China General Department Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China Department of Gastroenterology Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China Department of Thoracic Surgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina Department of Gastroenterology Aerospace Center HospitalPeking University Aerospace School of Clinical MedicineBeijing 100049China Cancer Research Center Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China

BACKGROUND Research on gastrointestinal mucosal adenocarcinoma(GMA)is limited and controversial,and there is no reference tool for predicting postoperative *** To investigate the prognosis of GMA and develop predictive *** From the Surveillance,Epidemiology,and End Results database,we collected clinical information on patients with *** random sampling,the patients were divided into the discovery(70%of the total,for model training),validation(20%,for model evaluation),and completely blind test cohorts(10%,for further model evaluation).The main assessment metric was the area under the receiver operating characteristic curve(AUC).All collected clinical features were used for Cox proportional hazard regression analysis to determine factors influencing GMA’s *** This model had an AUC of 0.7433[95% confidence intervals(95%CI):0.7424-0.7442]in the discovery cohort,0.7244(GMA:0.7234-0.7254)in the validation cohort,and 0.7388(95%CI:0.7378-0.7398)in the test *** packaged it into Windows software for doctors’use and uploaded *** gastric adenocarcinoma had the worst prognosis,and these were protective factors of GMA:Regional nodes examined[hazard ratio(HR):0.98,95%CI:0.97-0.98,P<0.001]and chemotherapy(HR:0.62,95%CI:0.58-0.66,P<0.001).CONCLUSION The deep learning-based tool developed can accurately predict the overall survival of patients with GMA *** surgery,chemotherapy,and adequate lymph node dissection during surgery can improve patient outcomes.

关键词： Deep learning Gastrointestinal mucous adenocarcinoma Overall survival Surgery Clinical tool