|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Clinical characteristics of 24 asymptomatic infections with COVID-19 screened among close contacts in Nanjing,China显示文摘Previous studies have showed clinical characteristics of patients with the 2019 novel coronavirus disease(COVID-19)and the evidence of person-to-person transmission.Limited data are available for asymptomatic infections.This study aims to present the clinical characteristics of 24 cases with asymptomatic infection screened from close contacts and to show the transmission potential of asymptomatic COVID-19 virus carriers.Epidemiological investigations were conducted among all close contacts of COVID-19 patients(or suspected patients)in Nanjing,Jiangsu Province,China,from Jan 28 to Feb 9,2020,both in clinic and in community.Asymptomatic carriers were laboratory-confirmed positive for the COVID-19 virus by testing the nucleic acid of the pharyngeal swab samples.Their clinical records,laboratory assessments,and chest CT scans were reviewed.As a result,none of the 24 asymptomatic cases presented any obvious symptoms while nucleic acid screening.Five cases(20.8%)developed symptoms(fever,cough,fatigue,etc.)during hospitalization.Twelve(50.0%)cases showed typical CT images of ground-glass chest and 5(20.8%)presented stripe shadowing in the lungs.The remaining 7(29.2%)cases showed normal CT image and had no symptoms during hospitalization.These 7 cases were younger(median age:14.0 years;P=0.012)than the rest.None of the 24 cases developed severe COVID-19 pneumonia or died.The median communicable period,defined as the interval from the first day of positive nucleic acid tests to the first day of continuous negative tests,was 9.5 days(up to 21 days among the 24 asymptomatic cases).Through epidemiological investigation,we observed a typical asymptomatic transmission to the cohabiting family members,which even caused severe COVID-19 pneumonia.Overall,the asymptomatic carriers identified from close contacts were prone to be mildly ill during hospitalization.However,the communicable period could be up to three weeks and the communicated patients could develop severe illness.These results highlighted the importance of close contact tracing and longitudinally surveillance via virus nucleic acid tests.Further isolation recommendation and continuous nucleic acid tests may also be recommended to the patients discharged. | Zhiliang Hu Ci Song Chuanjun Xu Guangfu Jin Yaling Chen Xin Xu Hongxia Ma Wei Chen Yuan Lin Yishan Zheng Jianming Wang Zhibin Hu Yongxiang Yi Hongbing Shen | 2020 | Science China(Life Sciences)2020，63，5： | 77 |
| 2 | R&D and application of voltage sourced converter based high voltage direct current engineering technology in China显示文摘As a new generation of direct current(DC)transmission technology,voltage sourced converter(VSC)based high voltage direct current(HVDC)has been widely developed and applied all over the world.China has also carried out a deep technical research and engineering application in this area,and at present,it has been stepped into a fast growing period.This paper gives a general review over China’s VSC based HVDC in terms of engineering technology,application and future development.It comprehensively analyzes the technical difficulties and future development orientation on the aspects of the main configurations of VSC based HVDC system,topological structures of converters,control and protection technologies,flexible DC cables,converter valve tests,etc.It introduces the applicable fields and current status of China’s VSC based HVDC projects,and analyzes the application trends of VSC based HVDC projects both in China and all over the world according to the development characteristics and demands of future power grids. | Guangfu TANG Zhiyuan HE Hui PANG | 2014 | Journal of Modern Power Systems and Clean Energy2014，2，1： | 55 |
| 3 | A DC Current Flow Controller for Meshed Modular Multilevel Converter Multiterminal HVDC Grids显示文摘This paper proposes the design of a novel DC current flow controller(CFC)and evaluates the control performance of balancing and regulating the DC branch currents using the DC CFC in a meshed multi-terminal HVDC(MTDC)grid.The DC CFC consists of two identical full bridge DC-DC converters with the capacitors of the two converters being connected in parallel.The scalability of the DC CFC is easily achievable due to the identical bridge converter topology;the cost of this DC CFC is also relatively low due to its simple physical structure and low voltage ratings.The control performance of the DC CFC is tested on a meshed 3-terminal(3-T)HVDC grid,which is based on modular multilevel converters(MMC).The DC branch current control in the meshed MTDC grid is achieved using the proposed control strategy of the DC CFC,and is verified through case studies on the real-time digital simulator(RTDS). | Na Deng Puyu Wang Xiao-Ping Zhang Guangfu Tang Junzheng Cao | 2015 | CSEE Journal of Power and Energy Systems2015，1，1： | 41 |
| 4 | Basic Topology and Key Devices of the Five-Terminal DC Grid显示文摘Due to their high controllability and flexibility,DC power grids have broad application prospects in the fields of networking of renewable energy and the power supply for oceanic archipelagos and future cities.This paper describes the system topology,control strategy,DC breaker configuration,and research,development and testing of converter valves and DC breaker equipment of the Zhoushan multi-terminal DC transmission system.Zhejiang Zhoushan has unique geographical and developmental features to demonstrate the irreplaceable technical advantages of a DC power grid for providing reliable power supply.The experience gained from the Zhoushan DC power grid project can offer valuable insights into the development and utilization of this technology worldwide. | Guangfu Tang Zhiyuan He Hui Pang Xiaoming Huang Xiao-Ping Zhang | 2015 | CSEE Journal of Power and Energy Systems2015，1，2： | 30 |
| 5 | Possible early Neoproterozoic magmatism associated with slab window in the Pingshui segment of the Jiangshan-Shaoxing suture zone: Evidence from zircon LA-ICP-MS U-Pb geochronology and geochemistry显示文摘We report here geochemical data, U-Pb zircon ages, and Hf isotopes for the high-Mg diorites (HMDs), Nb-enriched basaltic porphyrys (NEBPs) and plagiogranites (PLAGs) in the Pingshui segment of the Jiangshan-Shaoxing suture zone. The HMDs are characterized by high Mg# (>60), high Na and LREE contents, depletion of HREE and HFSE, and pronounced positive εNd(t) values of 7.0 to 7.7, similar to some adakitic high-Mg andesites. The NEBPs are relatively Na-rich (Na2O/K2O>6) and display high abundances of P2O5 (~1.00%), TiO2 (~3.08%) and HFSE (e.g., Nb=9.53-10.27 ppm). Their Nd isotopic compositions (εNd(t)=6.8-8.0) are comparable to those of the HMDs. The PLAGs are metaluminous (A/CNK=0.84-0.89) and sodic (Na2O/K2O>10). Their depletion in HFSE (e.g., Nb, Ta) is consistent with 'SSZ-type' plagiogranite. Zircon LA-ICP-MS U-Pb dating yields an age of 932±7 Ma for the HMD, 916±6 Ma for the NEBP, and 902±5 Ma for the PLAG, respectively, indicating that they were products of early Neoproterozoic magmatism. The PLAGs exhibit relatively high zircon Hf isotopes and positive εHf(t) values of 11.0 to 16.2, consistent with their Nd isotopic data (εNd(t)=7.5-8.4). Such features are similar to those of oceanic plagiogranites in ophiolites and distinct from those of crust-derived granites. The PLAGs were most likely derived from partial melting of subducted oceanic crust in an active continental margin. Considering these results in the context of the regional geology, we suggest that a slab window in the subducting oceanic crust between the Yangtze Block and Cathaysia Block was possibly the principal cause for the unique arc magmatism in the area. The upwelling asthenosphere below the slab window may have provided significant thermodynamic conditions. | CHEN ZhiHong GUO KunYi DONG YongGuan CHEN Rong LI LongMing LIANG YiHong LI ChunHai YU XiMing ZHAO Ling XING GuangFu | 2009 | Science China Earth Sciences2009，52，7： | 26 |
| 6 | Magma mixing of granites at Lianghe:In-situ zircon analysis for trace elements, U-Pb ages and Hf isotopes显示文摘In this paper, we report an integrated study of trace element, U-Pb age and Hf isotopic composition of zircons from alkali feldspar granites, granodiorites and diorite enclaves in a recently discovered ring complex at Lianghe in western Yunnan, Chi na. The granitoids showed identical U-Pb ages of 127, 115 and 122 Ma, from felsic to mafic, but had different zircon trace el ements and Hf isotopic compositions. Trace element content decreased with a gradual increase in εHf(t) values of ?9.1 to ?5.4, ?4.5 to 0, and 3.6 to 6.2, respectively. Results indicate that changes in zircon trace elements generally correlate with changes in Hf isotope signatures within single samples and among various granitoids. These relationships reflect the mixing of felsic and mafic magmas. Evidence indicates that depleted mantle-derived mafic magma underplating caused ancient crustal melting, and then formed large-scale granites in Lianghe during the Early Cretaceous. These granodiorites were formed mainly by the mix ing of mafic magma and granitic magma. | CONG Feng LIN ShiLiang ZOU GuangFu LI ZaiHui XIE Tao PENG ZhiMin LIANG Ting | 2011 | Science China Earth Sciences2011，54，9： | 26 |
| 7 | A DC Grid Benchmark Model for Studies of Interconnection of Power Systems显示文摘Reducing carbon emissions in the power sector is critical for transitioning to a sustainable and low-carbon future.Estimating carbon efficiency of demand side response(DSR)in the power system is an important step towards realizing potential environmental benefits.Marginal emission factor(MEF)is an effective tool for estimating incremental changes in carbon emissions as a result of a change in demand.However,estimation methods currently used for evaluating MEF can be improved upon,specifically,by factoring in the ramp-rate constraint of generators in the fuel cost based merit order dispatch.In this paper is described a new method for MEF assessment under ramp-rate constraints;the method is then compared with two conventional estimations in a British power system.Three fuel price scenarios are used to conduct a sensitivity analysis of MEFs to fuel prices.Conclusions are drawn that can pave the way for future improvements in estimating MEF in power systems. | Ting An Xiaoxin Zhou Congda Han Yanan Wu Zhiyuan He Hui Pang Guangfu Tang | 2015 | CSEE Journal of Power and Energy Systems2015，1，4： | 17 |
| 8 | Geochronology and Petrogenesis for the Protolith of Biotite Plagioclase Gneiss at Lianghe,Western Yunnan显示文摘在这份报纸,我们在西方的云南在 Lianghe 从黑云母斜长石片麻岩报导 U-Pb 年龄的综合研究和锆石的 Hf 同位素作文。锆石保存了继承核心和边界质地。火的锆石谷物和边界产出 120.4 的加权的吝啬的 206Pb/238U 年龄 ????晈 吗?? | CONG Feng LIN Shiliang ZOU Guangfu XIE Tao LI Zaihui TANG Fawei PENG Zhimin | 2011 | Acta Geologica Sinica(English Edition)2011，85，4： | 16 |
| 9 | Effects of Floating Ring Bearing Manufacturing Tolerance Clearances on the Dynamic Characteristics for Turbocharger显示文摘The inner and outer oil film dynamic characteristic coefficients of floating ring bearings(FRBs) change due to the manufacturing tolerance of the floating ring, journal and intermediate, which leads to high-speed turbocharger's vibration too large and even causes nonlinear vibration accident. However, the investigation of floating ring bearing manufacturing tolerance clearance on the rotordynamic characteristics is less at present. In order to study the influence law of inner and outer clearance on turbocharger vibration, the rotor dynamic motion equations of turbocharger supported in FRBs are derived by analyzing the size relations between floating ring, journal and intermediate for the inner and outer oil film clearances, the time transient response analysis for combination of FRBs clearance are developed. A realistic turbocharger is taken as a research object, the FE model of the turbocharger with FRBs is modeled. Under the conditions of four kinds of limit state bearing clearances for inner and outer oil film, the nonlinear transient analyses are performed based on the established FE dynamic models of the nonlinear rotor-FRBs system applied incentive combinations of gravity and unbalance force, respectively. From the waterfall, the simulation results show that the speed for the appearance of fractional frequency is not identical and the amplitude magnitude is different under the four kinds of bearing manufacturing tolerance limit clearances, and fractional frequency does not appear in the turbocharger and the amplitude is minimum under the ODMin/IDMax bearing manufacturing tolerance clearances. The turbocharger vibration is reduced by controlling the manufacturing tolerance clearance combinations of FRBs, which is helpful for the dynamic design and production-manufacturing of high-speed turbocharger. | WANG Longkai BIN Guangfu LI Xuejun ZHANG Xuefeng | 2015 | Chinese Journal of Mechanical Engineering2015，28，3： | 15 |
| 10 | Three-dimensional finite-time cooperative guidance for multiple missiles without radial velocity measurements显示文摘In order to simultaneously attack a target with impact angle constraint in threedimensional(3-D) space, a novel distributed cooperative guidance law for multiple missiles under directed communication topologies is proposed without radial velocity measurements. First, based on missiles-target 3-D relative motion equations, the multiple missiles cooperative guidance model with impact angle constraint is constructed. Then, in Line-of-Sight(LOS) direction, based on multiagent system cooperative control theory, one guidance law with directed topologies is designed with strict proof, which can guarantee finite time consensus of multiple missiles' impact times. Next, in elevation direction and azimuth direction of LOS, based on homogeneous system stability theory and integral sliding mode control theory, two guidance laws are proposed respectively with strict proof, which can guarantee LOS angles converge to desired values and LOS angular rates converge to zero in finite time. Finally, the effectiveness of the designed cooperative guidance law is demonstrated through simulation results. | Teng LYU Chuanjiang LI Yanning GUO Guangfu MA | 2019 | Chinese Journal of Aeronautics2019，32，5： | 14 |
| 11 | Preparation and characterization of Eu^(3+)-doped CaCO_3 phosphor by microwave synthesis显示文摘A Eu3+-doped CaCO3 phosphor with red emission was prepared by microwave synthesis. The scanning electron microscopy (SEM) image and laser particle size analysis show that the CaCO3:Eu3+ particles are needle-like in the length range of 5.0-10.0 μm. The results of X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy indicate that pure aragonite CaCO3:Eu3+ is prepared using microwave irradiation and the Eu3+ ion as a luminescence center inhabits the site of Ca2+. The photoluminescence excitation (PLE) spectrum shows that the strong broad band at around 270 nm and weak sharp lines in 300-550 nm are assigned to the charge transfer band of Eu3+-O2- and intra-configurational 4f-4f transitions of Eu3+, respectively. The photoluminescence (PL) spectrum implies that the red luminescence can be attributed to the transitions from the 5D0 excited level to the 7FJ (J = 0, 1, 2, 3, 4) levels of Eu3+ ions with the mainly electric dipole transition 5D0 → 7F2 (614 and 620 nm), and the Eu3+ ions prefer to occupy the low symmetric site in the crystal lattice. | KANG Ming LIU Jun YIN Guangfu SUN Rong | 2009 | Rare Metals2009，28，5： | 13 |
| 12 | Visible light-induced N-doped TiO_2 nanoparticles for the degradation of microcystin-LR显示文摘N-doped nano-crystalline TiO2 powders have been synthesized by the sol-gel method.The shape and crystal structure of the resulting N-doped TiO2 were investigated by X-ray Photoelectron Spectroscopy (XPS),X-ray spectroscopy (XRD),Transmission Electron Microscopy (TEM) and UV-vis reflection spectrum.The results showed that doping TiO2 with nitrogen can lower its band gap and apparently shift its optical response to the visible region.Under the visible light (λ> 420 nm) irradiation,the MC-LR was degraded by the synthesized N-TiO2 nano-material.The variation of MC-LR amount and its intermediates were detected by high performance liquid chromatography (HPLC) and LC-MS,respectively.The mineralization of MC-LR was determined by total organic carbon (TOC) analysis.Simultaneously,transient oxidative species generated during photocatalysis were tracked by electron spin resonance (ESR) and Peroxidase method.All these results indicated that visible-light excited N-TiO2 can activate molecular oxygen and thereby achieve degradation of MC-LR completely within 14 h.The removal of 59% of TOC was achieved after 20 h irradiation.The major oxidative species in the system were hydroxyl radical (·OH) and H2O2.13 Kinds of intermediates were primarily identified in the process.Based on these results,a reasonable conclusion was drawn for the degradation of MC-LR wherein its four positions are easy to be attacked by the photo-generated OH radical followed by the hydrolyzation of peptides. | YANG Jing,CHEN DengXia,DENG AnPing,FANG YanFen,LUO GuangFu,LI DeJiang,LI RuiPing & HUANG YingPing Alan G.MacDiarmid Research Institute of Renewable Energy,China Three Gorges University,Yichang 443000,China | 2010 | Science China Chemistry2010，53，8： | 12 |
| 13 | An Operational Test Method for VSC-HVDC Valves Based on Modular Multi-level Converters显示文摘为给基于模块化多电平换流器(modular multi-levelconverter,MMC)的电压源换流器高压直流输电(voltagesourced converter HVDC,VSC-HVDC)换流阀提供有效的检验手段,以验证其设计的正确性及其运行可靠性,对换流阀的运行特性和关键应力进行分析,提出基于原理等效的MMC阀运行试验方法,设计试验电路并阐明其运行机理。搭建的PSCAD电磁暂态仿真模型和实际的试验验证证明了试验方法的正确性和有效性。 | WU Yanan LU Tianguang TANG Guangfu ZHA Kunpeng GAO Chong | 2012 | 中国电机工程学报2012，32，30： | 12 |
| 14 | Molecular dynamics study on the relationships of modeling,structural and energy properties with sensitivity for RDX-based PBXs显示文摘In this paper,a primary model is established for MD(molecular dynamics) simulation for the PBXs(polymer-bonded explosives) with RDX(cyclotrimethylene trinitramine) as base explosive and PS as polymer binder.A series of results from the MD simulation are compared between two PBX models,which are represented by PBX1 and PBX2,respectively,including one PS molecular chain having 46 repeating units and two PS molecular chains with each having 23 repeating units.It has been found that their structural,interaction energy and mechanical properties are basically consistent between the two models.A systematic MD study for the PBX2 is performed under NPT conditions at five different temperatures,i.e.,195 K,245 K,295 K,345 K,and 395 K.We have found that with the temperature increase,the maximum bond length(L max) of RDX N N trigger bond increases,and the interaction energy(E N-N) between two N atoms of the N-N trigger bond and the cohesive energy density(CED) decrease.These phenomena agree with the experimental fact that the PBX becomes more sensitive as the temperature increases.Therefore,we propose to use the maximum bond length L max of the trigger bond of the easily decomposed and exploded component and the interaction energy E N-N of the two relevant atoms as theoretical criteria to judge or predict the relative degree of heat and impact sensitivity for the energetic composites such as PBXs and solid propellants. | XIAO JiJun ZHAO Li ZHU Wei CHEN Jun JI GuangFu ZHAO Feng WU Qiang XIAO HeMing | 2012 | Science China Chemistry2012，55，12： | 12 |
| 15 | Toeplitz operators on Fock-Sobolev spaces with positive measure symbols显示文摘We discuss Toeplitz operators on Fock-Sobolev space with positive measure symbols.By FockCarleson measure,we obtain the characterizations for boundedness and compactness of Toeplitz operators.We also give some equivalent conditions of Schatten p-class properties of Toeplitz operators by Berezin transform. | WANG XiaoFeng CAO GuangFu XIA Jin | 2014 | Science China Mathematics2014，57，7： | 11 |
| 16 | Unlocking the door to highly efficient Ag-based nanoparticles catalysts for NaBH4-assisted nitrophenol reduction显示文摘Ag-based nano particles(NPs)catalysts have recently attracted in creasi ng atte ntion in NaBH4-assisted n itrophe nol reducti on,especially in 4?n itrophe nol(4?NP)reducti on.Moreover,Ag-based NPs catalysts are con sidered to be very promising for practical applicati ons because of their fascinating advantages,e.g.,easy preparation,relatively low cost and less toxicity,high activity and good stability.Basically,the size and shape of Ag NPs are well known as the key factors for achieving highly efficient catalytic reduction of 4-NP.In this review,three highly efficient Ag-based NPs catalysts(supported Ag NPs,anisotropic Ag NPs and bimetallic Ag NPs)are highlighted for the 4-NP reduction,in eluding the catalytic mecha nism and reactio n rate caused by their adjustments in size and shape.Although high catalytic activity has bee n demonstrated by several Ag-based NPs catalysts,further improvement in the catalytic performance is still desired.In terms of the most recent progress in Ag-based NPs catalysts for 4?NP reduction,this review provides a comprehensive assessment on the material selection,synthesis and catalytic characterizations of these catalysts.Moreover,this review aims to correlate the catalytic performance of Ag-based NPs catalysts with their size and shape,guiding the development of novel cost-effective and high-performance catalysts. | Guangfu Liao Yan Gong Liu Zhong Jiasheng Fang Li Zhang Zushun Xu Haiyang Gao Baizeng Fang | 2019 | Nano Research2019，12，10： | 9 |
| 17 | Petrogenesis of keratophyes in the Pingshui Group,Zhejiang:Constraints from zircon U-Pb ages and Hf isotopes显示文摘Zircon LA-ICP-MS U-Pb ages and Hf isotopic as well as whole-rock geochemical data are reported for keratophyes in the Pingshui Group, Zhejiang. The results are used to discuss their petrogenesis and geological significance. The keratophyes were dated at 904±8 to 906±10 Ma. These intermediate-felsic rocks are characterized by high LREE contents and depletion of HREE and HFSE (e.g., Nb, Ta, Ti, P), resembling arc-derived rocks. The keratophyes exhibit positive εHf(t) values of 8.6 to 15.4, consistent with their εNd(t) values of 6.4 to 7.9 but far away from those of crust-derived rocks. Such features indi-cate that they were likely originated from prompt reworking of juvenile crust by arc-continent collision during the early-Neoproterozoic assembly between the Cathaysia and Yangtze Blocks. Combining with their Hf model ages, we suggest that there may exist not only remarkable growth of juvenile crust at ca.1.3―1.1 Ga but also production of juvenile arc-derived crust along the southeastern margin of the Yangtze Block (e.g., the Pingshui area) at ca.1.0―0.9 Ga. | CHEN ZhiHong XING GuangFu GUO KunYi DONG YongGuan CHEN Rong ZENG Yong LI LongMing HE ZhengYu ZHAO Ling | 2009 | Chinese Science Bulletin2009，54，9： | 9 |
| 18 | Stress Corrosion Cracking of Nitrogen-containing Stainless Steel 316LN in High Temperature Water Environments显示文摘Stress corrosion cracking(SCC) of stainless steels and Ni-based alloys in high temperature water coolant is one of the key problems affecting the safe operation of nuclear power plants(NPPs).The nitrogen-added stainless steel is a kind of possible candidate materials for mitigating SCC since reducing the carbon content and adding nitrogen to offset the loss in strength caused by the decrease in carbon content can mitigate the problem of sensitization.However,the reports of SCC of nitrogen-added stainless steels in high temperature water are few available.The effects of applied potential and sensitization treatment on the SCC of a newly developed nitrogen-containing stainless steel(SS) 316LN in high temperature water doped with chloride at 250 ℃ were studied by using slow strain rate tests(SSRTs).The SSRT results are compared with our data previously published for 316 SS without nitrogen and 304NG SS with nitrogen,and the possible mechanism affecting the SCC behaviors of the studied steels is also discussed based on SSRT and microstucture analysis results.The susceptibility to cracking of 316LN SS normally increases with increasing potential.The susceptibility to SCC of 316LN SS was less than that of 316 SS and 304NG SS.Sensitization treatment at 700 ℃ for 30 h showed little effect on the SCC of 316LN SS and significant effect on the SCC of 316 SS.The predominant cracking mode for the 316LN SS in both annealed state and the state after the sensitization treatment was transgranular.The presented conditions of mitigating stress corrosion cracking are some useful information for the safe use of 316LN SS in NPPs. | YANG Wu LI Guangfu HUANG Chunbo ZHOU Jianjiang LU Zhanpeng | 2010 | Chinese Journal of Mechanical Engineering2010，23，6： | 9 |
| 19 | Effects of Unbalance Location on Dynamic Characteristics of High-speed Gasoline Engine Turbocharger with Floating Ring Bearings显示文摘For the high-speed gasoline engine turbocharger rotor, due to the heterogeneity of multiple parts material, manufacturing and assembly errors, running wear in impeller and uneven carbon of turbine, the random unbalance usually can be developed which will induce excessive rotor vibration, and even lead to nonlinear vibration accidents. However, the investigation of unbalance location on the nonlinear high-speed turbocharger rotordynamic characteristics is less. In order to discuss the rotor unbalance location effects of turbocharger with nonlinear floating ring bearings(FRBs), the realistic turbocharger of gasoline engine is taken as a research object. The rotordynamic equations of motion under the condition of unbalance are derived by applied unbalance force and nonlinear oil film force of FRBs. The FE model of turbocharger rotor-bearing system is modeled which includes the unbalance excitation and nonlinear FRBs. Under the conditions of four different applied locations of unbalance, the nonlinear transient analyses are performed based on the rotor FEM. The differences of dynamic behavior are obvious to the turbocharger rotor systems for four conditions, and the bifurcation phenomena are different. From the results of waterfall and transient response analysis, the speed for the appearance of fractional frequency is not identical and the amplitude magnitude is different from the different unbalance locations, and the non-synchronous vibration does not occur in the turbocharger and the amplitude is relative stable and minimum under the condition 4. The turbocharger vibration and non-synchronous components could be reduced or suppressed by controlling the applied location of unbalance, which is helpful for the dynamic design, fault diagnosis and vibration control of the high-speed gasoline engine turbochargers. | WANG Longkai BIN Guangfu LI Xuejun LIU Dingqu | 2016 | Chinese Journal of Mechanical Engineering2016，29，2： | 9 |
| 20 | Delay Depending Decentralized Adaptive Attitude Synchronization Tracking Control of Spacecraft Formation显示文摘This paper deals with the problem of cooperative attitude tracking with time-varying communication delays as well as the delays between inter-synchronization control parts and self-tracking control parts in the spacecraft formation flying. First, we present the attitude synchronization tracking control algorithms and analyze the sufficient delay-dependent stability condition with the choice of a Lyapunov function when the angular velocity can be measured. More specifically, a class of linear filters is developed to derive an output feedback control law without having direct information of the angular velocity, which is significant for practical applications with low-cost configurations of spacecraft. Using a well-chosen Lyapunov-Krasovskii function, it is proven that the presented control law can make the spacecraft formation attitude tracking system synchronous and achieve exponential stability, in the face of model uncertainties, as well as non-uniform time-varying delays in communication links and different control parts. Finally, simulation results are presented to demonstrate the effectiveness of the proposed control schemes. | ZHOU Jiakang MA Guangfu HU Qinglei | 2012 | Chinese Journal of Aeronautics2012，25，3： | 8 |
您所在的机构暂未开通此部分的功能，请联系管理员