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47篇 您的检索式:作者名="Junyi Shen"
    题名 作者 年代 出处 被引量
1Preliminary assessment of the navigation and positioning performance of BeiDou regional navigation satellite system显示文摘BeiDou regional navigation satellite system(BDS)also called BeiDou-2 has been in full operation since December 27,2012.It consists of 14 satellites,including 5 satellites in Geostationary Orbit(GEO),5 satellites in Inclined Geosynchronous Orbit(IGSO),and 4 satellites in Medium Earth Orbit(MEO).In this paper,its basic navigation and positioning performance are evaluated preliminarily by the real data collected in Beijing,including satellite visibility,Position Dilution of Precision(PDOP)value,the precision of code and carrier phase measurements,the accuracy of single point positioning and differential positioning and ambiguity resolution(AR)performance,which are also compared with those of GPS.It is shown that the precision of BDS code and carrier phase measurements are about 33 cm and 2 mm,respectively,which are comparable to those of GPS,and the accuracy of BDS single point positioning has satisfied the design requirement.The real-time kinematic positioning is also feasible by BDS alone in the opening condition,since its fixed rate and reliability of single-epoch dual-frequency AR is comparable to those of GPS.The accuracy of BDS carrier phase differential positioning is better than 1 cm for a very short baseline of 4.2 m and 3 cm for a short baseline of 8.2 km,which is on the same level with that of GPS.For the combined BDS and GPS,the fixed rate and reliability of single-epoch AR and the positioning accuracy are improved significantly.The accuracy of BDS/GPS carrier phase differential positioning is about 35 and 20%better than that of GPS for two short baseline tests in this study.The accuracy of BDS code differential positioning is better than 2.5 m.However it is worse than that of GPS,which may result from large code multipath errors of BDS GEO satellite measurements.YANG YuanXi LI JinLong WANG AiBing XU JunYi HE HaiBo GUO HaiRong SHEN JunFei DAI Xian 2014Science China Earth Sciences2014,57,1:125
2Mode-division multiplexed transmission of wavelength-division multiplexing signals over a 100-km single-span orbital angular momentum fiber显示文摘We experimentally demonstrate mode-division multiplexed(MDM)transmission using eight orbital angular momentum(OAM)modes over a single span of 100-km low-attenuation and low-crosstalk ring-core fiber(RCF).Each OAM mode channel carries 10 wavelength-division multiplexing(WDM)signal channels in the C band,with each WDM channel in turn transmitting 16-GBaud quadrature phase-shift keying signal.An aggregate capacity of 2.56 Tbit/s and an overall spectral efficiency of 10.24 bit/(s·Hz)are realized.The capacity-distance product of 256(Tbit/s)·km is the largest reported so far for OAM fiber communications systems to the best of our knowledge.Exploiting the low crosstalk between the OAM mode groups in the RCF,the scheme only requires the use of modular 4×4 multiple-input multiple-output processing,and it can therefore be scaled up in the number of MDM channels without increasing the complexity of signal processing.Junwei Zhang Junyi Liu Lei Shen Lei Zhang Jie Luo Jie Liu Siyuan Yu 2020Photonics Research2020,8,7:8
3Shear-responsive boundary-lubricated hydrogels attenuate osteoarthritis显示文摘Lipid-based boundary layers formed on liposome-containing hydrogels can facilitate lubrication.However,these boundary layers can be damaged by shear,resulting in decreased lubrication.Here,a shear-responsive boundary-lubricated drug-loaded hydrogel is created by incorporating celecoxib(CLX)-loaded liposomes within dynamic covalent bond-based hyaluronic acid(HA)hydrogels(CLX@Lipo@HA-gel).The dynamic cross-linked network enables the hydrogel to get restructured in response to shear,and the HA matrix allows the accumulation of internal liposome microreservoirs on the sliding surfaces,which results in the formation of boundary layers to provide stable lubrication.Moreover,hydration shells formed surrounding the hydrogel can retard the degradation process,thus helping in sustaining lubrication.Furthermore,in vitro and in vivo experiments found that CLX@Lipo@HA-gels can maintain anabolic-catabolic balance,alleviate cartilage wear,and attenuate osteoarthritis progression by delivering CLX and shear-responsive boundary lubrication.Overall,CLX@Lipo@HA-gels can serve as shear-responsive boundary lubricants and drug-delivery vehicles to alleviate friction-related diseases like osteoarthritis.Yiting Lei Xingkuan Wang Junyi Liao Jieliang Shen Yuling Li Zhengwei Cai Ning Hu Xiaoji Luo Wenguo Cui Wei Huang 2022Bioactive Materials2022,7,10:4
4Tenofovir vs.entecavir on recurrence of hepatitis B virus-related hepatocellular carcinoma beyond Milan criteria after hepatectomy显示文摘Background:Hepatectomy for hepatocellular carcinoma(HCC)beyond the Milan criteria is shown to be beneficial.However,a high rate of post-operative HCC recurrence hinders the long-term survival of the patients.This study aimed to investigate and compare the impacts of tenofovir(TDF)and entecavir(ETV)on the recurrence of hepatitis B viral(HBV)-related HCC beyond the Milan criteria.Methods:Data pertaining to 1532 patients who underwent hepatectomy and received antiviral therapy between January 2014 and January 2019 were collected from five centers.Recurrence-free survival(RFS)analysis was performed using the Kaplan-Meier method.Cox proportional hazards regression analysis was performed to determine prognostic factors for HCC recurrence.Results:The analysis incorporates 595 HBV-related HCC patients.The overall 5-year RFS was 21.3%.Among them,533 and 62 patients received ETV and TDF treatment,respectively.The 1-,3-,and 5-year RFS rates were 46.3%,27.4%,and 19.6%,respectively,in the ETV group compared with 65.1%,41.8%,and 37.2%,respectively,in the TDF group(P<0.001).Multivariate analysis showed that TDF treatment(hazard ratio[HR]:0.604,P=0.005),cirrhosis(HR:1.557,P=0.004),tumor size(HR:1.037,P=0.008),microvascular invasion(MVI)(HR:1.403,P=0.002),portal vein tumor thrombus(PVTT)(HR:1.358,P=0.012),capsular invasion(HR:1.228,P=0.040),and creatinine levels(CREA)(HR:0.993,P=0.031)were statistically significant prognostic factors associated with RFS.Conclusions:Patients with HCC beyond the Milan criteria exhibited a high rate of HCC recurrence after hepatectomy.Compared to the ETV therapy,TDF administration significantly lowered the risk of HCC recurrence.Junyi Shen Weili Qi Junlong Dai Shusheng Leng Kangyi Jiang Yu Zhang Shun Ran Chuan Li Tianfu Wen 2022Chinese Medical Journal2022,,3:3
5Grey Prediction Based Software Stage-Effort Estimation显示文摘The software stage-effort estimation can be used to dynamically adjust software project schedule,further to help make the project finished on budget. This paper presents a grey model Verhulst based method for stage-effort estimation during software development process,a bias correction technology was used to improve the estimation accuracy. The proposed method was evaluated with a large-scale industrial software engineering data-base. The results are very encouraging and indicate the method has considerable potential.WANG Yong SONG Qinbao SHEN Junyi 2007Wuhan University Journal of Natural Sciences2007,12,5:3
6Electromagnetic Confinement and Shaping for Plate-Form Part显示文摘The relationship between melt shape, electromagnetic pressure and magnetic field is studied for electromagnetic confinement and shaping of plate-form part. The results of experimental observation and theoretical inference can be summarized as follows. As the melt thickness a is large enough, causing the ratio of plate thickness to current theoretic skin depth α/δ larger than 2.2, the electromagnetic pressure acting on melt can be simply expressed as Pm =2μ\B2, and the melt shape would be known only by measuring the distribution of magnetic flux density. As α is small and makes the ratio α/δless than 2.2, the melt shape and electromagnetic pressure for confining and shaping are determined not only by magnetic flux density B but also by melt thickness a, electromagnetic parameter pry and current frequency f. In this paper, an equation used to calculate electromagnetic pressure acting on 'thin plate-form melt' is brought forward. The equation gives a precise relationship between electromagnetic pressure factor p and melt thickness α, electromagnetic parameter μγ and current frequency f.Jun SHEN, Jianguo LI and Hengzhi FU (State Key Laboratory of Solidification Processing, Northwestern Polytechnic University, Xi’an 710072, China) Junyi SU (Xi’an Jiaotong University,Xi’an 710049, China) 2000Journal of Materials Science & Technology2000,16,1:2
7High-performance modified uni-traveling carrier photodiode integrated on a thin-film lithium niobate platform显示文摘Lithium niobate on insulator(LNOI)has become an intriguing platform for integrated photonics for applications in communications,microwave photonics,and computing.Whereas,integrated devices including modulators,resonators,and lasers with high performance have been recently realized on the LNOI platform,high-speed photodetectors,an essential building block in photonic integrated circuits,have not been demonstrated on LNOI yet.Here,we demonstrate for the first time,heterogeneously integrated modified uni-traveling carrier photodiodes on LNOI with a record-high bandwidth of 80 GHz and a responsivity of 0.6 A/W at a 1550-nm wavelength.The photodiodes are based on an n-down In GaAs/InP epitaxial layer structure that was optimized for high carrier transit time-limited bandwidth.Photodiode integration was achieved using a scalable wafer die bonding approach that is fully compatible with the LNOI platform.XIANGWEN GUO LINBO SHAO LINGYAN HE KEVIN LUKE JESSE MORGAN KEYE SUN JUNYI GAO TA-CHING TZU YANG SHEN DEKANG CHEN BINGTIAN GUO FENGXIN YU QIANHUAN YU MASOUD JAFARI MARKO LONčAR MIAN ZHANG ANDREAS BELING 2022Photonics Research2022,10,6:2
8Classification of multivariate time series using two-dimensional singular value decomposition显示文摘WENG Xiaoqing SHEN Junyi 2008Knowledge-based systems2008,21,7:1
91-Pbps orbital angular momentum fibre-optic transmission显示文摘Space-division multiplexing(SDM),as a main candidate for future ultra-high capacity fibre-optic communications,needs to address limitations to its scalability imposed by computation-intensive multi-input multi-output(MIMO)digital signal processing(DSP)required to eliminate the crosstalk caused by optical coupling between multiplexed spatial channels.By exploiting the unique propagation characteristics of orbital angular momentum(OAM)modes in ring core fibres(RCFs),a system that combines SDM and C+L band dense wavelength-division multiplexing(DWDM)in a 34 km 7-core RCF is demonstrated to transport a total of 24960 channels with a raw(net)capacity of 1.223(1.02)Peta-bit s−1(Pbps)and a spectral efficiency of 156.8(130.7)bit s−1 Hz−1.Remarkably for such a high channel count,the system only uses fixed-size 4×4 MIMO DSP modules with no more than 25 time-domain taps.Such ultra-low MIMO complexity is enabled by the simultaneous weak coupling among fibre cores and amongst non-degenerate OAM mode groups within each core that have a fixed number of 4 modes.These results take the capacity of OAM-based fibre-optic communications links over the 1 Pbps milestone for the first time.They also simultaneously represent the lowest MIMO complexity and the 2nd smallest fibre cladding diameter amongst reported few-mode multicore-fibre(FM-MCF)SDM systems of>1 Pbps capacity.We believe these results represent a major step forward in SDM transmission,as they manifest the significant potentials for further up-scaling the capacity per optical fibre whilst keeping MIMO processing to an ultra-low complexity level and in a modularly expandable fashion.Junyi Liu Jingxing Zhang Jie Liu Zhenrui Lin Zhenhua Li Zhongzheng Lin Junwei Zhang Cong Huang Shuqi Mo Lei Shen Shuqing Lin Yujie Chen Ran Gao Lei Zhang Xiaobo Lan Xinlun Cai Zhaohui Li Siyuan Yu 2022Light(Science & Applications)2022,11,8:1
10Reexamining the Relations between Socio-Demographic Characteristics and Individual Environmental Concern: Evidence from Shanghai Data 显示文摘Shen Junyi Tatsyoshi Saijo 2008Journal of Environmental Psychology2008,28,1:1
11Application Server Aging Model and Multi-Level Rejuvenation Strategy Using Semi-Markov Process显示文摘Aiming at the characteristic of the dependency between the application components and the application server platform, a rejuvenation strategy with two different levels of rejuvenation granularities is put forward in this paper including the application component rejuvenation and the application server system rejuvenation. The availability and maintenance cost functions are obtained by means of establishing the application server aging model and the boundary condition of the optimal rejuvenation time is analyzed. Theory analysis indicates that the two-level rejuvenation strategy is superior to the traditional single level one. Finally, evaluation experiments are carried out and numerical result shows that compared with the traditional rejuvenation policy, the rejuvenation strategy proposed in this paper can further increase availability of the application server and reduce maintenance cost.ZHAO Tianhai QI Yong SHEN Junyi HOU Di ZHENG Xiaomei LIU Liang 2006Wuhan University Journal of Natural Sciences2006,11,5:1
12Optimiza- tion of sizing and battery cycle life in battery/uhracapaci- tor hybrid energy storage systems for electric vehicle ap- plications显示文摘Shen Junyi Dusmez Serkan Khaligh Alireza 2014IEEE Trans on Industrial Informatics2014,10,4:1
13Design and Implement of Personalized Distance Education System Based on Web Usage Mining显示文摘Jiangchun Song Junyi Shen 2006通讯和计算机(中英文版)2006,3,7:1
14Efficient data mining for web navigation patterns 显示文摘Dongshan Xing Junyi Shen 2004Information and Software Technology2004,46,:1
15An Incremental Algorithm of Text Clustering Based on Semantic Sequences显示文摘This paper proposed an incremental textclustering algorithm based on semantic sequence. Using similarity relation of semantic sequences and calculating the cover of similarity semantic sequences set, the candidate cluster with minimum entropy overlap value was selected as a result cluster every time in this algorithm. The comparison of experimental results shows that the precision of the algorithm is higher than other algorithms under same conditions and this is obvious especially on long documents set.FENG Zhonghui SHEN Junyi BAO Junpeng 2006Wuhan University Journal of Natural Sciences2006,11,5:1
16Efficient data mining for web navigation patterns显示文摘Dongshan Xing Junyi Shen 2003Information and Software Technology2003,,1:1
17An Approach on Automatic Test Data Generation with Predicate Constraint Solving Technique显示文摘Chen Jifeng Zhu Li Shen Junyi 2006International Journal of Information Technology2006,12,3:1
18A simultaneous estimation of environmental kuznets curve:Evidence from China显示文摘SHEN Junyi 2006China Economic Review2006,17,2:1
19A simultaneous estimation of environmental Kuznets curve: Evidence from China 显示文摘SHEN Junyi 2006China Economic Review2006,,17:1
20A simultaneous estimation of environmental Kuznets curve : evidence from China 显示文摘Shen Junyi 2006China Economic2006,17,4:1
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