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基于仿真方法的共享换电站价值量化分析

北京工业大学学报 2025年第1期51卷 22-31页

作者：沙玲汪静张海峰王岱上海工程技术大学机械与汽车工程学院上海201620 上海蔚来汽车有限公司上海201800

相较于电动汽车充电站,换电站具有补能时间短、空间面积小等优点。多品牌电动汽车高效共享换电站,能够极大程度优化补能结构,减少资源浪费。为了量化共享换电站对电动汽车用户的价值,基于排队理论,利用蔚来汽车品牌的运行数据,搭建一个... 详细信息

相较于电动汽车充电站,换电站具有补能时间短、空间面积小等优点。多品牌电动汽车高效共享换电站,能够极大程度优化补能结构,减少资源浪费。为了量化共享换电站对电动汽车用户的价值,基于排队理论,利用蔚来汽车品牌的运行数据,搭建一个模拟用户换电行为的仿真器,通过量化用户的平均排队时间和换电站数量,评估电动汽车用户在不同电动汽车规模和换电站渗透率下的换电体验。结果表明,电动汽车品牌共享换电站资源,能够显著减少电动汽车用户的排队时间,以及将排队时间保持在期望阈值内所需的换电站数量,从而提高用户的充电体验并节省换电站建设成本。

关键词：电动汽车换电站共享排队论换电体验仿真

Carrier frequency offset estimation for a generalized OFDMA uplink

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High Technology Letters 2011年第4期17卷 333-338页

作者： Zhang Wei wang jing Chen xiang State Key Laboratory on Microwave and Digital Communications Tsinghua National Laboratory for Information Science and Technology Department of Electronic Engineering Tsinghua University Beijing 100084 P.R.China College of Informatlon and Commumcation Engineering Harbin Engineering University Harbin 150001P.R.China

A residual carrier frequency offset （CFO） estimation scheme is proposed for the uplink of orthogonal frequency division multiple access （OFDMA） systems. Multiple access interference caused by CFOs in the uplink is investigated, as it severely affects the performance of a classical maximum likelihood （ML） frequency estimator. By the use of the estimated CFOs of the active users, the linear maximum mean square error （LMMSE） equalization is performed before the ML frequency estimator for the interference cancellation, which can help to sufficiently improve the estimation accuracy for the residual CFO of the incoming user. Analysis and simulations show that the modified ML estimator provides a tradeoff between estimation accuracy and computational complexity caused by the LMMSE interference cancellation, and the proposed method allows OFDMA systems flexibly allocating subcarriers to users.

关键词： OFDMA upliak frequency synchronization maximum likelihood (ML) frequency estimator linear minhnum mean square error (LMMSE) equalization generalized carrier-allocation scheme (GCAS)

Low-temperature dielectric relaxation associated with NbO_6 octahedron distortion in antimony modified potassium sodium niobate ceramics

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Journal of Materials Science & Technology 2022年第20期115卷 189-198页

作者： Nan Zhang xiang Lv Xi-xiang Zhang jing Lyu Shuo-wang Yang Jiagang Wu Department of Materials Science Sichuan UniversityChengdu 610065China Division of Physical Science and Engineering King Abdullah University of Science and TechnologyThuwal 23955-6900Saudi Arabia Department of Chemistry National University of Singapore3 Science Drive 3117543Singapore Institute of High Performance Computing Agency for ScienceTechnology and Research1 Fusionopolis Way#16-16 Connexis138632Singapore

Although the antimony(Sb) has been widely used to modify potassium sodium niobate(KNN) ceramics for tailoring the phase structure and performance, the role of Sb still remains insufficiently understood,consequently hindering the understanding of the physical origin of high-performance KNN-based ceramics. Here, we combine the experiments and first-principles calculations to deeply reveal the effects of Sb on KNN ceramics. Our results reveal a re-entrant-like relaxation behavior near the rhombohedralorthorhombic(R-O) phase transition at the low content of Sb, which transforms into a canonical one at higher content of Sb. First-principles calculations show a significantly decreased difference in the bond length of six B-O bonds of Nb O6 octahedral in Sb-modified KNN ceramics compared to pristine KNN ceramics, responsible for the low-temperature re-entrant-like dielectric relaxation. Furthermore, the addition of Sb would soften the B-O repulsion and gradually break the long-range ferroelectric ordering,resulting in the occurrence of nanoscale domains and enhanced local heterogeneity. Finally, we find that the optimized piezoelectric properties are the trade-off between the long-range ferroelectric ordering and the local heterogeneity. Therefore, this work not only deeply reveals the effects of Sb on KNN ceramics from multi-scale perspectives but also helps the future composition design for achieving high piezoelectricity.

关键词： KNN-based ceramics Re-entrant-like relaxation Covalency Multiphase coexistence Local heterogeneity

QBFO-BOMP Based Channel Estimation Algorithm for mmWave Massive MIMO Systems

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Computer Modeling in Engineering & Sciences 2023年第11期137卷 1789-1804页

作者： Xiaoli jing Xianpeng wang xiang Lan Ting Su State Key Laboratory of Marine Resource Utilization in South China Sea and School of Information and Communication Engineering Hainan UniversityHaikou570228China

At present,the traditional channel estimation algorithms have the disadvantages of over-reliance on initial conditions and high *** bacterial foraging optimization(BFO)-based algorithm has been applied in wireless communication and signal processing because of its simple operation and strong self-organization *** the BFO-based algorithm is easy to fall into local ***,this paper proposes the quantum bacterial foraging optimization(QBFO)-binary orthogonal matching pursuit(BOMP)channel estimation algorithm to the problem of local ***,the binary matrix is constructed according to whether atoms are selected or *** the support set of the sparse signal is recovered according to the BOMP-based ***,the QBFO-based algorithm is used to obtain the estimated channel *** optimization function of the least squares method is taken as the fitness *** on the communication between the quantum bacteria and the fitness function value,chemotaxis,reproduction and dispersion operations are carried out to update the bacteria *** results showthat compared with other algorithms,the estimationmechanism based onQBFOBOMP algorithm can effectively improve the channel estimation performance of millimeter wave(mmWave)massive multiple input multiple output(MIMO)***,the analysis of the time ratio shows that the quantization of the bacteria does not significantly increase the complexity.

关键词： Channel estimation bacterial foraging optimization quantum bacterial foraging optimization binary orthogonal matching pursuit massive MIMO

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转变教育思想实施素质教育

唐都学刊 2001年第3期17卷 107-110页

作者：杜向民王景荣黎新军长安大学陕西西安710064

教育思想的转变是实施素质教育的前提。教育思想观念要实现以下转变 :从单纯的专业教育向综合素质教育转变 ;从重理工轻人文向文理并重转变 ;在教学观上变“三中心”为“三注重” ;在学生的素质培养上 ,变重智主义的片面发展为整体素质... 详细信息

教育思想的转变是实施素质教育的前提。教育思想观念要实现以下转变 :从单纯的专业教育向综合素质教育转变 ;从重理工轻人文向文理并重转变 ;在教学观上变“三中心”为“三注重” ;在学生的素质培养上 ,变重智主义的片面发展为整体素质的和谐发展 ;在学校教育与就业的关系上 ,变一次性教育为终身教育 ;在对待集体与个人的关系上 ,确立集体主义与个性和谐发展相统一的观念。

关键词：教育思想素质教育终身教育文理并重

Effect of sintering temperature on the physical properties and electrical contact properties of doped AgSnO_2 contact materials

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1275-1285页

作者： Hai-tao wang Zi-xiang wang Lian-zheng wang jing-qin wang Yan-cai Zhu State Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Electrical EngineeringHebei University of Technology Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province School of Electrical EngineeringHebei University of Technology

AgSnO_ 2 electrical contact materials doped with Bi_2O_3,La_2O_3,and TiO_2 were successfully fabricated by the powder metallurgy method under different initial sintering *** electrical conductivity,density,hardness,and contact resistance of the Ag Sn O_2/Bi_2O_3,AgSnO_2/La_2O_3,and AgSnO_2/Ti O_2 contact materials were measured and *** arc-eroded surface morphologies of the doped AgSnO_2 contact materials were investigated by scanning electron microscopy(SEM).The effects of the initial sintering temperature on the physical properties and electrical contact properties of the doped AgSnO_2 contact materials were *** results indicate that the physical properties can be improved and the contact resistance of the AgSnO_2 contact materials can be substantially reduced when the materials are sintered under their optimal initial sintering temperatures.

关键词： sintering temperature contact materials physical properties electrical contact properties

Sintilimab-induced autoimmune diabetes:A case report and review of the literature

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World Journal of Clinical Cases 2022年第4期10卷 1263-1277页

作者： jing Yang Ying wang xiang-Min Tong Clinical Laboratory Center Zhejiang Provincial People’s HospitalHangzhou 310014Zhejiang ProvinceChina Clinical Research Institute Zhejiang Provincial People’s HospitalHangzhou 310014Zhejiang ProvinceChina Department of Hematology Clinical Trial InstituteZhejiang Provincial People’s HospitalHangzhou 310014Zhejiang ProvinceChina

BACKGROUND With the widespread application of immune checkpoint inhibitor(ICI)therapy,the number of immune-related adverse effects(irAEs)has increased over the *** diabetes mellitus(DM)is a rare irAEs of ICIs and can be troublesome and life *** SUMMARY We report a 78-year-old woman with no history of diabetes who presented with hyperglycemia up to 23.4 mmol/L(random blood glucose level)after 14 courses of *** A1c was 8.2%,fasting insulin was 0.29 mIU/mL,and fasting C-peptide was decreased to a level with negative *** her medical history and laboratory examination,she was diagnosed with programmed cell death(PD)-1-inhibitor-induced,new-onset autoimmune *** controlling her blood glucose,she was treated with daily insulin by subcutaneous *** was allowed to continue anti-PD-1 therapy and she still obtained some therapeutic *** also reviewed some published cases(n=36)of PD-1/PD-ligand 1(PD-L1)inhibitor-induced *** also discuss potential pathogenic mechanisms,clinical features,prognostic markers(βcell antibodies,human leukocyte antigen type,PD-L1 Level)of this rare adverse *** It is important for all clinicians to be aware of DM as an irAEs of ICIs.

关键词： Sintilimab Immune related adverse effects Small cell lung cancer Autoimmune diabetes Case report

Is it possible to foot reflexology for infants with sensorineural hearing loss?

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World Journal of Clinical Cases 2025年第2期13卷 1-4页

作者： Min Ai Hang-Hang Zhang Jun-Bang Feng Chuan-Ming Li Wen-jing wang Meng-Die Hu Department of Anesthesiology Nanan District People's Hospital of ChongqingChongqing 400060China Department of Breast and Thyroid Surgery Chongqing Bishan District Maternal and Child Health Care HospitalChongqing 402760China Department of Medical Imaging Chongqing University Central HospitalChongqing 400014China

Foot reflexology is a non-invasive and safe complementary therapy that works by massaging the reflex zones of the feet and exerts systemic or whole-body regulation through meridian nerve *** therapy is commonly used in the treatment of various conditions such as autism and Parkinson's ***,there is limited reporting on the use of foot reflexology therapy for infants with sensorineural hearing loss(SNHL).Currently,there is no definitive conclusion on how foot reflexology therapy can influence *** editorial holds some guiding significance regarding this clinical *** aim is to present physiological evidence of how foot reflexology therapy can impact infants with SNHL,thereby enhancing clinician’s awareness of foot reflexology in treating infants with SNHL.

关键词： Foot reflexology Sensorineural Hearing Loss Future perspectives Limitations Neural conduction

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体外受精-胚胎移植妊娠数目与母儿结局分析

生殖医学杂志 2010年第2期19卷 91-94页

作者：吴庚香杨菁徐望明尹太郎胡静武汉大学人民医院生殖医学中心武汉430060

目的探讨体外受精-胚胎移植(IVF-ET)妊娠数目与母儿结局的关系。方法回顾性分析我中心2005年1月至2007年9月IVF-ET术后受孕322例,比较单胎妊娠及多胎妊娠母儿结局。结果临床妊娠322例,分娩243例,多胎妊娠率为27.6%(89/322)。多胎妊娠各... 详细信息

目的探讨体外受精-胚胎移植(IVF-ET)妊娠数目与母儿结局的关系。方法回顾性分析我中心2005年1月至2007年9月IVF-ET术后受孕322例,比较单胎妊娠及多胎妊娠母儿结局。结果临床妊娠322例,分娩243例,多胎妊娠率为27.6%(89/322)。多胎妊娠各种并发症中妊高征发生率最高(25.42%),多胎妊娠组其卵巢过度刺激综合征(OHSS)以及胎膜早破、妊高征等妊娠并发症的发病率均明显高于单胎妊娠组(P<0.05),单胎妊娠者其孕龄及新生儿出生体重均大于双胎妊娠者(P<0.01)。结论IVF-ET术后多胎妊娠率较高,多胎妊娠者其OHSS、胎膜早破、妊高征等并发症及早产、低出生体重儿发病率均较单胎妊娠者高,应限制胚胎移植数目以改善IVF-ET妊娠后母儿结局。

关键词：体外受精-胚胎移植妊娠结局多胎妊娠