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Novel disjoint path selection scheme based on link availability in ASON

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 70-73页

作者： WANG Xian-qing LU yue-ming ji yue-feng Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and TelecommunicationsBeijing 100876 China

Risk-disjoint routing is an efficient way to improve network survivability. In this article, a partial risk-disjoint routing algorithm based on link availability （PRDRA-LA） is proposed based on the complete risk-disjoint routing algorithm （CRDRA）. While calculating the protection path with PRDRA-LA, the links that share risks with the links in the working path are filtered by link availability. In addition, the risk disjoint degree between the protection path and the working path can be adjusted freely. Simulation results showed that when compared with CRDRA, routing connections with PRDRA-LA can achieve improved survivability while the number of connections that can be successfully routed over the current network is kept from serious decline.

关键词： automatically switched optical network risk- sharing links partial risk-disjoint routing algorithm based on link availability risk-disjoint degree

Ultrabroad Microwave Absorption Ability and Infrared Stealth Property of Nano-Micro CuS@rGO Lightweight Aerogels

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Nano-Micro Letters 2022年第11期14卷 1-17页

作者： yue Wu yue Zhao Ming Zhou Shujuan Tan Reza Peymanfar Bagher Aslibeiki Guangbin ji College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China Department of Chemical Engineering Energy Institute of Higher EducationSavehIran Faculty of Physics University of TabrizTabriz 51666-16471Iran

Developing ultrabroad radar-infrared compatible stealth materials has turned into a research hotspot,which is still a problem to be ***,the copper sulfide wrapped by reduced graphene oxide to obtain three-dimensional(3D)porous network composite aerogels(CuS@rGO)were synthesized via thermal reduction ways(hydrothermal,ascorbic acid reduction)and freeze-drying *** was discovered that the phase components(rGO and CuS phases)and micro/nano structure(microporous and nanosheet)were well-modified by modulating the additive amounts of CuS and changing the reduction ways,which resulted in the variation of the pore structure,defects,complex permittivity,microwave absorption,radar cross section(RCS)reduction value and infrared(IR)***,the obtained CuS@rGO aerogels with a single dielectric loss type can achieve an ultrabroad bandwidth of 8.44 GHz at 2.8 mm with the low filler content of 6 wt%by a hydrothermal ***,the composite aerogel via the ascorbic acid reduction realizes the minimum reflection loss(RL_(min))of−60.3 dB with the lower filler content of 2 wt%.The RCS reduction value can reach 53.3 dB m^(2),which effectively reduces the probability of the target being detected by the radar ***,the laminated porous architecture and multicomponent endowed composite aerogels with thermal insulation and IR stealth ***,this work offers a facile method to design and develop porous rGO-based composite aerogel absorbers with radar-IR compatible stealth.

关键词： Microwave absorption Ultrabroad bandwidth Composite aerogel Radar cross section Radar-infrared compatible stealth

Model analysis and resonance suppression of wide-bandwidth inertial reference system

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Nanotechnology and Precision Engineering 2019年第4期2卷 177-187页

作者： Dong Li TengfeiWu yue ji Xingfei Li State Key Laboratory of Precision Measurement Technology and Instruments Tianjin UniversityTianjin 300072China Key Laboratory of Advanced Electrical Engineering and Energy Technology Tianjin Polytechnic UniversityTianjin 30087China

In the fields of earth observation,deep space detection,laser communication,and directional energyweapon,the target needs to be observed and pointed at ***,tracking,and pointing(ATP)systems are usually designed to stabilize the line of sight(LOS)within sub-micro radian *** the case of an ATP system mounted on a mobile platform,angular disturbances experienced by the mobile platform will seriously affect the *** overcome the problemthat the sampling frequency of detectors is usually limited and achieving several hundreds of hertz is difficult,thewide-bandwidth inertial reference system(WBIRS)and fast steeringmirror are usually integrated into ATP systems to mitigate these angular *** reduce the structural stress,a flexible support providing two rotational degrees of freedomis usually adopted for the ***,the occurrence of resonant points within the bandwidthwill be *** have to be taken to compensate these low-frequency resonant points to realize a wide bandwidth and high *** this paper,the lowfrequency resonant points of a systemwere simulated using finite element analysis and tested by a systemidentification *** results show that the first-order resonance happened at 34.5 Hz with a gain of 28 *** improved double-T notch filter was designed and applied in a real-time system to suppress the resonance at 34.5 *** experimental results show that the resonance was significantly *** particular,the resonance peak was reduced by 79.37%.In addition,the closed-loop system settling time was reduced by 36.2%.

关键词： Resonance suppression Notch filter System identification Inertial reference

The Monotone Method for Controllability of the Nonlinear Evolution Systems

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Acta Mathematicae Applicatae Sinica 2011年第4期27卷 721-726页

作者： yue LU Yong LI Ming-ji LIU College of Mathematics Jilin University Changchun 130012 China

In this paper, we study the controllability of the nonlinear evolution systems. We establish the controllability results by using the monotone operator theory. No compactness assumptions are imposed in the main result... 详细信息

关键词： controllability monotone operator nonlinear control systems

Channel Estimation for One-Bit Massive MIMO Based on Improved CGAN

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Journal of Communications and Information Networks 2022年第2期7卷 214-220页

作者： Yongli An jinking yue Lei Chen Zhanlin ji School of Artificial Intelligence North China University of Science and TechnologyTangshan 063000China. Key Laboratory of Industrial Intelligent Perception of Hebei Province Tangshan 063000China

In the one-bit massive multiple-input multiple-output(MIMO)channel scenario,the accurate channel estimation becomes more difficult because the signals received by the low-resolution analog-to-digital converters(ADC)are quantized and affected by channel ***,a one-bit massive MIMO channel estimation method is proposed in this *** channel matrix is regarded as a two-dimensional *** order to enhance the significance of noise features in the image and remove them,the channel attention mechanism is introduced into the conditional generative adversarial network(CGAN)to generate channel images,and im-prove the loss *** simulation results show that the improved network can use a smaller number of pilots to obtain better channel estimation *** the same number of pilots and signal-to-noise ratio(SNR),the channel estimation accuracy can be improved by about 7.5 dB,and can adapt to the scenarios with more antennas.

关键词： channel estimation massive MIMO condi-tional generative adversarial network attention mecha-nism denoising

Supporting multi-user real-time VBR video service using dynamic bandwidth management based on prediction

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 64-71页

作者： XU Zhi-yuan LI Hui LU yue-ming ji yue-feng Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

Real-time variable bit rate（VBR） video is expected to take a significant portion of multimedia ***,plentiful challenges to VBR video service provision have been raised for its characteristic of high traffic *** support multi-user real-time VBR video transmission with high bandwidth utilization and satisfied quality of service（QoS）,this article proposes a practical dynamic bandwidth management *** scheme forecasts future media rate of VBR video by employing time-domain adaptive linear predictor and using media delivery index（MDI） as both QoS measurement and complementary management *** addition,to support multi-user application,an adjustment priorities classified strategy is also put ***,a test-bed based on this management scheme is *** experimental results demonstrate that the scheme proposed in this article is efficient with bandwidth utilization increased by 20%-60% compared to a fixed service rate and QoS guaranteed.

关键词： dynamic bandwidth management MDI QoS real-time time-domain adaptive linear predictor VBR video

Flexible scheduling ensuring inter-ONU-group fairness in 1G/10G EPON coexistence system

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 16-22页

作者： LI Qi LI Hui ji yue-feng Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

In recent years, 10 Gbit/s Ethemet passive optical networks （10G EPON） have been gaining considerable interests because of its high bandwidth capability. To ensure smooth transition from 1 Gbit/s to 10 Gbit/s equipment and to avoid a significant one-time investment into such a cost-sensitive market, coexistence of gigabit Ethernet passive optical networks （GEPON） and 10G EPON system are necessary. In this article, coexistence system architecture and a novel bandwidth allocation algorithm called weight-optimized dynamic bandwidth allocation for coexistence EPON （WOCE-DBA） for the system is proposed. The simulation results show that this algorithm can guarantee fair bandwidth sharing among different optical network unit （ONU） groups, without ignoring the inter-ONU and intra-ONU fairness. Most importantly, it can flexibly adapt to the system composition variations and save efforts needed to modify the bandwidth scheduling mechanism during the migration process from GEPON to 10G EPON.

关键词： 10G EPON coexistence system dynamic bandwidth allocation (DBA) intra-ONU-group fairness simulation and modeling

Effects of Bivalirudin and Unfractionated Heparin on Liver and Renal Function in Chinese Patients with Coronary Artery Disease Undergoing Coronary Angiography with/without Percutaneous Coronary Intervention

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Journal of Clinical and Translational Hepatology 2021年第4期9卷 477-483页

作者： Qiaowei jia jia Hu Wenfeng ji Liansheng Wang Enzhi jia Department of Cardiovascular Medicine First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsuChina Department of Cardiovascular Medicine Liyang People’s HospitalLiyangJiangsuChina

Background and Aims:Unfractionated heparin(UFH)and bivalirudin are widely used as anticoagulants in cardiovascular medicine,including for thrombosis prevention during coronary angiography(CAG)and percutaneous coronary intervention(PCI).Little is known of the effects of UFH and bivalirudin on liver and kidney function in patients subjected to these *** study compared the effects of bivalirudin and UFH on liver/renal function in patients with coronary artery disease who underwent CAG,with or without ***:The study comprised 134 consecutive patients(40–89 years-old),who underwent CAG(or CAG and PCI);among them,66 and 68 patients were subject to,respectively,bivalirudin or *** following indicators of liver/renal function were measured before and after the procedures:plasma alanine aminotransferase(ALT),aspartate aminotransferase(AST),blood urea nitrogen,estimated glomerular filtration rate(eGFR),creatinine clearance,and serum *** were further stratified by severity of chronic kidney disease(CKD),based on original ***:Relative to baseline,in the bivalirudin group,ALT and AST were higher after CAG(p=0.005,0.025),while blood urea nitrogen and serum creatinine were lower(p=0.049,<0.001).In the UFH group,ALT,AST,eGFR,and creatinine clearance were lower after CAG(p≤0.001,all).Patients given bivalirudin with moderate or severe CKD,but not those with mild CKD,gained significant improvement in kidney ***:Relative to UFH,bivalirudin may better safeguard the renal function of patients with coronary artery disease who undergo CAG,especially patients with moderate-to-severe renal *** may cause less liver damage than bivalirudin.

关键词： Bivalirudin Unfractionated heparin Coronary artery disease Coro-nary angiography Percutaneous coronary intervention Liver function

Strain- and twist-engineered optical absorption of few-layer black phosphorus

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Science China(Physics,Mechanics & Astronomy) 2016年第9期59卷 86-92页

作者： Qian jia XiangHua Kong jingSi Qiao Wei ji Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices Renmin University of China Beijing 100872 China

Density functional and many-body perturbation theories calculations were carried out to investigate fundamental and optical bandgap, exciton binding energy and optical absorption property of normal and strain- and twist-engineered few-layer black phosphorus （BP）. We found that the fundamental bandgaps of few layer BP can be engineered by layer stacking and in-plane strain, with linear relationships to their associated exciton binding energies. The strain-dependent optical absorption behaviors are also anisotropic that the position of the first absorption peak monotonically blue-shifts as the strain applies to either direction for incident light polarized along the armchair direction, but this is not the case for that along the zigzag direction. Given those striking properties, we proposed two prototype devices for building potentially more balanced light absorbers and light filter passes, which promotes further applications and investigations of BP in nanoelectronics and optoelectronics.

关键词： black phosphorus light absorption strain-engineering exciton binding energy