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Variability Analysis for a Two-station Queueing Network in Heavy Traffic with Arrival Processes Driven by Queues

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 445-466页

作者： jian CAO Yong-jiang guo Kai-ming YANG School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The law of the iterated logarithm(LIL)for the performance measures of a two-station queueing network with arrivals modulated by independent queues is developed by a strong approximation *** convenience,two arrival processes modulated by queues comprise the external system,all others are belong to the internal *** is well known that the exogenous arrival has a great influence on the asymptotic variability of performance measures in *** the considered queueing network in heavy traffic,we get all the LILs for the queue length,workload,busy time,idle time and departure processes,and present them by some simple functions of the primitive *** LILs tell us some interesting insights,such as,the LILs of busy and idle times are zero and they reflect a small variability around their fluid approximations,the LIL of departure has nothing to do with the arrival process,both of the two phenomena well explain the service station’s situation of being busy all the *** external system shows us a distinguishing effect on the performance measures:an underloaded(overloaded,critically loaded)external system affects the internal system through its arrival(departure,arrival and departure together).In addition,we also get the strong approximation of the network as an auxiliary result.

关键词： two-station queueing network the law of the iterated logarithm(LIL) strong approximation fluid approximation

A Mothed of Improving Identification Accuracy via Deep Learning Algorithm under Condition of Deficient Labeled Data

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A Mothed of Improving Identification Accuracy via Deep Learn...

Processing of a low-costγ-γ'NiPtAl coating with improved oxidation resistance

第36届中国控制会议

作者： jian-guo wang Zhi-Duo Cao Bang-Hua Yang Shi-Wei Ma Min-Rui Fei Hao wang Yuan Yao Tao Chen Xiao-Fei wang School of Mechatronical Engineering and Automation Shanghai UniversityShanghai Key Lab of Power Station Automation Technology Department of Chemical Engineering “Tsing-Hua University” Department of Chemical and Process Engineering University of Surrey Shanghai Zhenhua Heavy Industries Company Limited

ISBN: (纸本)9781538629185

In industrial process, some important variables such as quality index, efficiency index and concentration of product components are difficult or even impossible to be measured directly due to the limitation of technology. This phenomenon leads to few labeled data and plenty of unlabeled data. Traditional identification method for controlled auto regressive（CAR） model usually cannot deal with unlabeled training data. As a result, these traditional identification methods may receive poor identification precision or even cannot work entirely. To solve the problems above, this paper proposes a new identification method based on deep learning（DL）. Firstly, the CAR model is transformed into finite impulse response（FIR） model solve the problem of lack of autoregressive part;Secondly, autoencoder of deep learning make full use of unlabeled data to pretrain the model;Thirdly, small amount of label data is used for fine-tuning. As a semi-supervised learning method, deep learning can be able to extract more information from unlabeled data than traditional supervised learning method. The results show that the proposed method can acquire higher identification accuracy than BP neural network.

关键词： System Identification Deep Learning Controlled Auto Regressive Finite Impulse Response

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Rare Metals 2024年第6期43卷 2832-2841页

作者： Yan jiang Liang-Liang Wei jian He Hong-Bo guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structural Materials and Protective Coatings Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

A novelγ-γ'(Ni solid solution—Ni_(3)Al)NiPtAl coating was produced on advanced single-crystal(SC)superalloy N5 by electroplating of a thin Pt coating with~3μm in thickness followed by heat treatment at 1000℃in *** comparison,a traditionalγ-γ'NiPtAl coating was also produced by electroplating of a thick Pt coating with~6μm in thickness followed by heat treatment at 1100℃in *** novel coating has a mass gain of~0.5 mg·cm^(-2)after 100 h 1-h cyclic oxidation at 1150℃,showing better oxidation resistance than the traditional *** oxide scale mostly consisting ofα-Al_(2)O_(3)grew on the novel coating because the element Cr from the SC alloy substrate contributes to the formation ofα-Al_(2)O_(3).Pt content in the novel coating has significant effect on the oxidation *** optimized Pt content in the coating is about 16 at%,which is helpful to reduce the diffusion of harmful elements from the substrate into the coating but also to reduce the cost of the coating.

关键词： γ-γ'NiPtAl coating Platinum Oxidation Al_(2)O_(3) Superalloy

A Compact UHF Antenna Based on Hilbert Fractal Elements and a Serpentine Arrangement for Detecting Partial Discharg

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Energy Engineering 2024年第5期121卷 1127-1141页

作者： Xiang Lin jian Fang Ming Zhang Kuang Yin Yan Tian Yingfei guo Qianggang wang Guangzhou Power Supply Bureau of Guangdong Power Grid Co. Ltd.China Southern Power GridGuangzhou510620China State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqing400044China

Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency(UHF)antennas for detecting partial discharge(PD)as a common precursor to ***,the effectiveness of existing UHF antennas suffers from a number of challenges such as limited bandwidth,relatively large physical size,and low detection *** present study addresses these issues by proposing a compact microstrip patch antenna with fixed dimensions of 100 mm×100 mm×1.6 *** results of computations yield an optimized antenna design consisting of 2nd-order Hilbert fractal units positioned within a four-layer serpentine arrangement with a fractal unit connection distance of 3.0 ***,the optimized antenna design achieves a detection bandwidth for which the voltage standing wave ratio is less than 2 that is approximately 97.3%of the UHF frequency range(0.3–3 GHz).Finally,a prototype antenna is fabricated using standard printed circuit board technology,and the results of experiments demonstrate that the proposed antenna is capable of detecting PD signals at a distance of 8 m from the discharge source.

关键词： Power system fault partial discharge UHF antenna fractal antenna micro-strip antenna

Genetically modified pigs:Emerging animal models for hereditary hearing loss

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Zoological Research 2024年第2期45卷 284-291页

作者： Xiao wang Tian-Xia Liu Ying Zhang Liang-Wei Xu Shuo-Long Yuan A-Long Cui Wei-Wei guo Yan-Fang wang Shi-Ming Yang jian-guo Zhao State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 100049China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China Department of Otolaryngology-Head and Neck Surgery Institute of OtolaryngologyChinese PLA General HospitalBeijing 100853China Division of Life Sciences and Medicine University of Science and Technology of ChinaHefeiAnhui 230022China State Key Laboratory of Animal Biotech Breeding Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing100193China

Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for *** investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are *** have been extensively used as valuable large animal models in biomedical *** this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing ***,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL ***,this review provides insights and perspectives for future studies on HHL using porcine models.

关键词： Pigs Animal models Hereditary hearing loss Genetic modification Inner ear

Debye-screening effect on electron-impact excitation of helium-like Al^(11+)and Fe^(24+)ions

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Chinese Physics B 2022年第4期31卷 299-304页

作者： Yu-Long Ma Ling Liu Lu-You Xie Yong Wu Deng-Hong Zhang Chen-Zhong Dong Yi-Zhi Qu jian-guo wang College of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070China Key Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Center for Applied Physics and Technology Peking UniversityBeijing 100084China School of Optoelectronics University of Chinese Academy of SciencesBeijing 100049China

Debye-screening effects on the electron-impact excitation(EIE)processes for the dipole-allowed transition 1 s_(2)^(1)S→1 s2 p^(1)P in He-like Al^(11+)and Fe^(24+)ions are investigated using the fully relativistic distorted-wave methods with the Debye-Huckel(DH)model ***-screening effects on the continuum-bound(CB)interaction and target ion are discussed,both of which result in reduction of EIE cross *** reduction due to screening on the CB interaction is *** non-spherical and spherical DH potentials are adopted for considering the screening effect on the CB *** is found that the spherical DH potential could significantly overestimate the influence of plasma screening on EIE cross sections for multielectron He-like ions.

关键词： Debye plasmas electron-impact excitation Debye-Hückel model potential He-like Al^(11+)and Fe^(24+)ions

Three-dimensional cell-based strategies for liver regeneration

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BIOCELL 2024年第7期48卷 1023-1036页

作者： DAN guo XI XIA jian YANG Liver Transplant Center Transplant CenterWest China HospitalSichuan UniversityChengdu610041China Frontiers Medical Center Tianfu Jincheng LaboratoryChengdu610212China

Liver regeneration and the development of effective therapies for liver failure remain formidable challenges in modern *** recent years,the utilization of 3D cell-based strategies has emerged as a promising approach for addressing these urgent clinical *** review provides a thorough analysis of the application of 3D cell-based approaches to liver regeneration and their potential impact on patients with end-stage liver ***,we discuss various 3D culture models that incorporate hepatocytes and stem cells to restore liver function and ameliorate the consequences of liver ***,we explored the challenges in transitioning these innovative strategies from preclinical studies to clinical *** collective insights presented herein highlight the signiﬁcance of 3D cell-based strategies as a transformative paradigm for liver regeneration and improved patient care.

关键词： Three-Dimensional Liver regeneration Organoids Stem cells Cell therapy

Structures and ion transport mechanisms of plant high-affinity potassium transporters

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Molecular Plant 2024年第3期17卷 409-422页

作者： jiangqin wang Yanping Luo Fan Ye Zhong Jie Ding Shao jian Zheng Shuai Qiao Yong wang jiangtao guo Wei Yang Nannan Su international Institutes of Medicine the Fourth Affiliated HospitalZhejang University School of MedicineYiwuZhejiang 322000China Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital Zhejiang University School of MedicineHangzhouZhejang 310058China State Key Laboratory of Plant Environmental Resilience College of Life SciencesZhejang UniversityHangzhouZhejang 310058China College of Life Sciences Zhejiang UniversityHangzhouZhejiang 310058China NHC and CAMS Key Laboratory of Medical Neurobiology MOE Frontier Science Center for Brain Science and Brain-machine IntegrationSchool of Brain Science and Brain MedicineZhejiang UniversityHangzhouZhejiang 310058China Nanhu Brain-computer Interface Institute Hangzhou.Zheiang 311100.China

Plant high-affinity K^(+) transporters(HKTs)mediate Na^(+) and K^(+) uptake,maintain Na^(+)/K^(+) homeostasis,and therefore play crucial roles in plant salt *** this study,we present cryoelectron microscopy structures of HKTs from two classes,classI HKT1;1 from Arabidopsis thaliana(AtHKT1;1)and class II HKT2;1 from Triticum aestivum(TaHKT2;1),in both Na^(+) -and K^(+) -bound states at 2.6-to 3.0-A ***1;1and TaHKT2;1function *** HKT subunit consists of four tan-dem domain units(D1-D4)with a repeated K^(+) -channel-like M-P-M *** each subunit,D1-D4 assemble into an ion conduction pore with a pseudo-four-fold *** both TaHKT2;1and AtHKT1;1 have only one putative Na^(+) ion bound in the selectivity filter with a similar coordination pattern,the two HKTs display different K^(+) binding modes in the ***2;1 has three K^(+) ions bound in the selec-tivity filter,but AtHKT1;1 has only two K^(+) ions bound in the filter,which has a narrowed external entrance due to the presence of a Ser residue in the first filter *** structures,along with compu-tational,mutational,and electrophysiological analyses,enable us to pinpoint key residues that are critical for the ion selectivity of *** findings provide new insights into the ion selectivity and ion transport mechanisms of plant HKTs and improve our understanding about how HKTs mediate plant salt tolerance and enhance crop growth.

关键词： HKTs structure ion selectivity mechanism salt tolerance

Combined use of fly ash and silica to prevent the long-term strength retrogression of oil well cement set and cured at HPHT conditions

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Petroleum Science 2024年第2期21卷 1122-1134页

作者： guo-Dong Cheng Xue-Yu Pang Jin-Sheng Sun Zheng-Song Qiu Chuang-Chuang wang jian-Kun Qin Ning Li School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Oil and Gas Engineering Research Institute(Tarim Oilfield Company) China National Petroleum CorporationTarim841000XinjiangChina

The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy development. Previous attempts to address this problem has been unsatisfactory because they can only reduce the strength decline rate. This study presents a new solution to this problem by incorporating fly ash to the traditional silica-cement systems. The influences of fly ash and silica on the strength retrogression behavior of oil well cement systems directly set and cured under the condition of 200°C and 50 MPa are investigated. Test results indicate that the slurries containing only silica or fly ash experience severe strength retrogression from 2 to 30 d curing, while the slurries containing both fly ash and silica experience strength enhancement from 2 to 90 d. The strength test results are corroborated by further evidences from permeability tests as well as microstructure analysis of set cement. Composition of set cement evaluated by quantitative X-ray diffraction analyses with partial or no known crystal structure(PONKCS) method and thermogravimetry analyses revealed that the conversion of amorphous C-(A)-S-H to crystalline phases is the primary cause of long-term strength *** addition of fly ash can reduce the initial amount of C-(A)-S-H in the set cement, and its combined use with silica can prevent the crystallization of C-(A)-S-H, which is believed to be the working mechanism of this new admixture in improving long-term strength stability of oil well cement systems.

关键词： Fly ash Long-term strength retrogression High temperature Quantitative X-ray diffraction(QXRD) Partial or no known crystal structure(PONKCS)