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| 1 | Reliable transmission of consultative committee for space data systems file delivery protocol in deep space communication显示文摘In consultative committee for space data systems(CCSDS) file delivery protocol(CFDP) recommendation of reliable transmission,there are no detail transmission procedure and delay calculation of prompted negative acknowledge and asynchronous negative acknowledge models.CFDP is designed to provide data and storage management,story and forward,custody transfer and reliable end-to-end delivery over deep space characterized by huge latency,intermittent link,asymmetric bandwidth and big bit error rate(BER).Four reliable transmission models are analyzed and an expected file-delivery time is calculated with different trans-mission rates,numbers and sizes of packet data units,BERs and frequencies of external events,etc.By comparison of four CFDP models,the requirement of BER for typical missions in deep space is obtained and rules of choosing CFDP models under different uplink state informations are given,which provides references for protocol models selection,utilization and modification. | Hui Li Hao Luo Faxin Yu Zheming Lu | 2010 | Journal of Systems Engineering and Electronics2010，21，3： | 7 |
| 2 | Coseismic response of groundwater level in the Three Gorges well network and its relationship to aquifer parameters显示文摘The 12 May 2008 Ms 8.0 Wenchuan earthquake caused notable changes in the water levels of wells in the Three Gorges area. This work examines the relationship between these coseismic changes in water level and the changes in aquifer parameters. Three wells in the area with good responses to earth tide were chosen for analysis. Water-level data from February to June 2008 were used to calculate the aquifer transmissivity, permeability and specific storage of the rocks, and analyze the relationship between the coseismic responses of the wells and their aquifer parameters. The results show that the Wenchuan earthquake changed these parameters considerably, thereby controlling co- and postseismic variations of water level. The values of these parameters prior to the earthquake are linearly related with the amplitudes of coseismic variations in water level. The larger the aquifer transmissivity, the more remarkable the coseismic change in water level. During the earthquake, changes in aquifer parameters were found to be associated with coseismic variations in water level, with the larger changes occurring when the coseismic variation in water level was larger. The tectonic setting has a certain degree of influence on the co- and postseismic changes in water level. The permeability structures of the fault zone appear to determine the manner of coseismic variation in water level. Moreover, it seems that the water level in wells where groundwater converges more easily can recover faster following an earthquake. Insight from this study helps to improve understanding of the characteristics of water-level changes caused by earthquakes. | SHI ZheMing WANG GuangCai LIU ChengLong MEI JianChang WANG JinWei FANG HuiNa | 2013 | Chinese Science Bulletin2013，58，25： | 6 |
| 3 | Abnormal interruption of water flow from an artesian well prior to 2008 Wenchuan earthquake显示文摘Water flow from an artesian well stopped on December 17,2007 but recovered when the Wenchuan Ms 8.0 earthquake occurred on May 12,2008.This well is located 90 km south of the epicenter in an extensional tectonic setting,where similar changes of water level and resistivity were observed at two other nearby sites.Our investigation suggests that this phenomenon was not caused by environmental disturbances,such as drought or borehole-drilling activity,but might be a precursor to the earthquake. | Liu Chenglong Che Yongtai Xu Yinju Shi Zheming Yang Xianhe | 2011 | Geodesy and Geodynamics2011，2，2： | 5 |
| 4 | Multipurpose Watermarking Algorithm for Secret Communication显示文摘 | LU Zheming LI Suzhi | 2006 | Chinese Journal of Electronics2006，15，1： | 3 |
| 5 | Crack dynamic propagation properties and arrest mechanism under impact loading显示文摘Crack dynamic propagation and arrest behaviors have received extensive attention over the years.However,there still remain many questions,e.g.under what conditions will a running crack come to arrest?In this paper,drop weight impact(DWI)tests were conducted to investigate crack arrest mechanism using single cleavage triangle(SCT)rock specimens.Green sandstone was selected to prepare the SCT specimens.Dynamic stress intensity factors(DSIFs)were calculated by ABAQUS code,and the critical DSIFs were determined by crack propagation speeds and fracture time measured by crack propagation gauges(CPGs).The test results show that the critical DSIF at propagation decreases with crack propagation speed.Numerical simulation for SCT specimens under different loading waves was performed using AUTODYN code.The reflected compressive wave from the incident and transmitted plates can induce crack arrests during propagation,and the number of arrest times increases with the wave length.In order to eliminate the effect of the incident and transmitted plates,models consisting of only one SCT specimen without incident and transmitted plates were established,and the same trapezoid-shaped loading wave was applied to the SCT specimen.The results show that for the SCT specimen with transmitted boundary(analogous to an infinite plate),the trapezoid-shaped loading wave cannot induce crack arrest anymore.The numerical results can well describe the occurrence of crack arrest in the experiments. | Yuqing Dong Zheming Zhu Li Ren Lei Zhou Peng Ying Meng Wang | 2020 | Journal of Rock Mechanics and Geotechnical Engineering2020，12，6： | 3 |
| 6 | Evaluation of the range of horizontal stresses in the earth’s upper crust by using a collinear crack model显示文摘 | Zheming Zhu | 2013 | Journal of Applied Geophysics2013，，： | 3 |
| 7 | Stress intensity factor for a cracked specimen under compression显示文摘 | Zheming Zhu Laigui Wang Bibhu Mohanty Chengyi Huang | 2005 | Engineering Fracture Mechanics2005，，4： | 3 |
| 8 | Numerical prediction of crater blasting and bench blasting显示文摘 | Zheming Zhu | 2009 | International Journal of Rock Mechanics and Mining Sciences2009，，6： | 3 |
| 9 | Numerical investigation of blasting-induced damage in cylindrical rocks显示文摘 | Zheming Zhu Heping Xie Bibhu Mohanty | 2007 | International Journal of Rock Mechanics and Mining Sciences2007，，2： | 3 |
| 10 | Efficacy of Phacovitrectomy Combined with Internal Limiting Membrane Peeling for Macular Diseases显示文摘Purpose:To observe the efficacy of vitrectomy with internal limiting membrane.(ILM) peeling combined with phacoemulsification with intraocular lens.(IOL) implantation in the treatment of cataract with co-existing macular diseases.Methods:A total of 28 cataract patients (28 eyes) with coexisting macular diseases were admitted to Aier Eye Hospital between May 2008 and May 2011.The clinical characteristics were analyzed in this study.Subjects included 6 men and 22 women,aged from 56 to 77 years (mean 64 years),with duration of disease ranging from 2 to 36 months (mean 9.3 months).All patients underwent phacoemulsification with implantation of a hydrophobic acrylic IOL into the capsular bag and pars plana vitrectomy with ILM peeling.Results:Postoperatively,patients underwent 3-to 18-months of follow-up.(mean 7.2 months).Only one eye had macular hole failing to close.Normal macular structure was restored in the other 27 eyes.The presenting visual acuity and best corrected visual acuity.(BCVA) did not differ significantly (t =-1.724,P =0.096),with the BCVA in 27 eyes.(96.4%).improving by 2 lines or more.The improvement in minimum angle of resolution.(MAR).was > 0.3 in 21 eyes,≥0.1 in 6 eyes and<0.1 in 1 eye.The mean spherical equivalent.(SE) was-4.67±5.98D preoperatively and-0.38±0.69D postoperatively (t=4.157,P<0.005).Conclusion:Combined phacovitrectomy surgery is a reliable and safe procedure in the treatment of cataract complicated by macular disease. | Zheming Wu Jinglin Zhang Yun Chen Rulong Gao Zhende Lin | 2012 | Eye Science2012，27，1： | 3 |
| 11 | Numerical investigation of blasting-induced crack initiation and propagation in rocks显示文摘 | Zheming Zhu Bibhu Mohanty Heping Xie | 2006 | International Journal of Rock Mechanics and Mining Sciences2006，，3： | 3 |
| 12 | Synthesis,crystal structures, and magnetic properties of two three-dimensional octacyanotungstate(IV)-based bimetallic frameworks with 4,4′-bipyridine dioxide (4,4′-dpdo)显示文摘The reaction of [HN(n-C4H9)3]3[WV(CN)8]·4H2O, 4,4′-bipyridine dioxide(4,4′-dpdo), and MnCl2·4H2O or CuCl2·2H2O gives two new three-dimensional octacyanometalate-based bimetallic assemblies, {[Mn2 (4,4′-dpdo)(H2O)4] [WIV(CN)8]}·6H2O (1) and {[Cu2(4,4′-dpdo)(H2O)][W(CN)8]}·CH3OH·H2O (2). Compound 1 crystallizes in the orthorhombic system, space group P21212 with cell constants a=10.397(2) -, b= 11.321(2) -, c=12.295(3) - and Z=2, whereas 2 crystallizes in the monoclinic system, space group P21/c with cell constants a=13.038(3) -, b=13.784(3) -, c=13.225(3) -, β=93.44(3)o and Z=4. In complex 1, each [WIV(CN)8]4- unit with a square antiprismatic geometry is connected to four Mn2 dimers through four bridging CN- ions forming wavelike alternating -W-Mn2-W-Mn2- layers, which are further linked through 4,4′-dpdo ligands coordinated to the Mn ions into a three-dimensional open framework. In complex 2, each [WIV(CN)8]4- ion still adopts a square antiprismatic geometry, whereas it bonds to seven copper ions through seven CN- ions leading to cage-like undulate layers further bridged by 4,4′-dpdo ligands into a three-dimensional network. Due to the bridging role of the long rigid 4,4′-dpdo ligand, there exist plenty of large cavities in the open frameworks of complexes 1 and 2 occupied by solvent clusters containing H2O or CH3OH molecules. To our knowledge, it is noted that 4,4′-dpdo displays a μ-4,4,4′,4′ m ode, which was first experimentally observed, although predicted before. Magnetic studies show that complex 1 displays an antiferromagnetic coupling between MnⅡ ions, while complex 2 ex-hibits a weak ferromagnetic interaction between CuⅡ ions. | YUAN Mei GAO Song ZHAO Fei ZHANG Wen WANG ZheMing | 2009 | Science China Chemistry2009，52，3： | 3 |
| 13 | Advances in research on earthquake fluids hydrogeology in China:a review显示文摘Monitoring of subsurface fluid(underground fluid)is an important part of efforts for earthquake prediction in China.The nationwide network,which monitors groundwater level,water temperature,and radon and mercury in groundwater,has been constructed in the last decades.Large amounts of abnormal fluid changes before and after major earthquakes have been recorded,providing precious data for research in earthquake sciences.Many studies have been done in earthquake fluid hydrogeology in order to probe the nature of the earthquake.Much progress in earthquake fluid hydrogeology has been made in the last decades.The paper provides a review of the advances in research on earthquake fluid hydrogeology over the last40 years in China.It deals with the following five aspects:(1)an introduction to the development history of monitoring networks construction;(2)cases of different subsurface fluid changes recorded before some majorearthquakes which occurred in the last decades;(3)characteristics of subsurface fluid changes following major earthquakes;(4)mechanism of subsurface fluid changes before and following earthquakes;(5)application of earthquake fluids in the hydrogeology field. | Zheming Shi Guangcai Wang Chenglong Liu | 2013 | Earthquake Science2013，26，6： | 3 |
| 14 | Relationship between the Earth tidal factor and phase lag of groundwater levels in confined aquifers and the Wenchuan M_s8.0 earthquake of 2008显示文摘This work focuses on variations of the Earth tidal factor and phase lag derived from groundwater observations before and after major earthquakes.It is based on an analysis of the data from four observational wells at boundaries between distinct active blocks of China mainland.These wells are also situated on several active fault zones and have exhibited considerable responses to the Wenchuan Ms8.0 earthquake of 2008 in China.We collected hourly records of water levels of these wells from 2007to 2009 and processed these data for analysis.The tidal factors,phase lags,and phase-difference changes of tidal residuals of each well were calculated.We found that when the Wenchuan quake happened,the tidal factors of the 4 wells were changing rapidly,while their phase lags and phase differences of tidal residuals declined swiftly,which may reflect the stress and strain changes of the well-aquifer system during the seismic generation. | SHI ZheMing WANG GuangCai | 2013 | Science China Earth Sciences2013，56，10： | 3 |
| 15 | The Effect of Loading Rates on Crack Dynamic Behavior Under Medium-Low Speed Impacts显示文摘Rock structures are often subjected to dynamic loads,such as blasts,impacts and earthquakes,and their loading rates differ largely.To investigate the effect of loading rates on the dynamic behavior of crack propagation,impact tests were conducted on large single-cleavage semicircle compression(LSCSC)specimens using a drop weight impact test system.Five types of rock materials were selected to prepare the LSCSC specimens,and crack propagation gauges were mounted along the crack propagation paths to measure crack initiation time and propagation speeds.Finite element models were established by using ABAQUS code,and the dynamic stress intensity factors(SIFs)were calculated.The curves of dynamic SIFs versus time were obtained,and the initiation toughness was determined by using these curves and the initiation time measured in the impact tests.The results show that loading rate has a significant effect on crack propagation behavior,and both the crack propagation speed and initiation toughness increase with the loading rate,whereas the delayed fracture time decreases with the increase in loading rate. | Peng Ying Zheming Zhu Lei Zhou Meng Wang Yuqing Dong Hao Qiu | 2019 | Acta Mechanica Solida Sinica2019，32，1： | 2 |
| 16 | The mixed boundary problems for a mixed mode crack in a finite plate显示文摘 | Zheming Zhu | 1997 | Engineering Fracture Mechanics1997，，5： | 2 |
| 17 | Experimental and Numerical Study of Shear Fracture in Brittle Materials with Interference of Initial Double Cracks显示文摘A simultaneous experimental and numerical study of shear fracture of concrete-like materials is carried out using Brazilian disc specimens with initial double edge cracks and fourpoint bending beam specimens with double edge-notches.The interference effects of two cracks/notches are investigated through varied ligament angles and crack lengths.It is shown that shear fracturing paths change remarkably with the initial ligament angles and crack lengths.The cracked specimens are numerically simulated by an indirect boundary element method.A comparison between the numerical results and the experimental ones shows good agreement. | Hadi Haeri Vahab Sarfarazi Mohammad Fatehi Marji Ahmadreza Hedayat Zheming Zhu | 2016 | Acta Mechanica Solida Sinica2016，29，5： | 2 |
| 18 | Effect of disconnector and high-voltage conductor on propagation characteristics of PD-induced UHF signals显示文摘UHF(ultra high frequency)method has been widely used in PD(partial discharge)detection for its high sensitivity.The resonance,distortion,and attenuation appearing in the propagation process of UHF signals in GIS(gas insulated switchgear)will influence the real situation of PD detection.Therefore,it is necessary to investigate the effect of GIS components such as disconnectors or high voltage conductors on the propagation characteristics of PD-induced UHF signals in various voltage classes GIS.The factors of PD signals propagation characteristics in axial and radial directions are both analysed to avoid the effect caused by placement of sensor in this paper.First,the simulation models of GIS are built based on FDTD(finite difference time domain)method.Then the propagation characteristics of PD-induced UHF signals are studied in the GIS with different disconnector gap lengths and different high voltage conductor radii.Finally,the reliability of the simulation results is verified by compared with laboratory tests.The disconnector gap and the change of conductor radii can both result in the signals attenuation which rises highest in the direction of 180°.The lower the GIS class voltage is,the larger the attenuation of signals after passing through disconnector gap is. | Minxia Shi Xutao Han Xuanrui Zhang Zheming Zhang Junhao Li | 2018 | High Voltage2018，3，3： | 2 |
| 19 | Study on the mechanism of zonal disintegration around an excavation显示文摘 | Zheming Zhu Chao Wang Jiming Kang Yuanxin Li Meng Wang | 2014 | International Journal of Rock Mechanics and Mining Sciences2014，，： | 2 |
| 20 | Non-equal-interval direct optimizing Verhulst model that x(n) be taken as initial value and its application显示文摘To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) of X(0) as the starting condition of the grey differential model. It optimizes a modified β value and the background value, and takes two times fitting optimization. The new model extends equal intervals to non-equal-intervals and is suitable for general data modelling and estimating parameters of the direct Verhulst GM(1,1). The new model does not need to pre-process the primitive data, nor accumulate generating operation (AGO) and inverse accumulated generating operation (IAGO). It is not only suitable for equal interval data modelling, but also for non-equal interval data modelling. As the new information is fully used and two times fitting optimization is taken, the fitting accuracy is the highest in all existing models. The example shows that the new model is simple and practical. The new model is worth expanding on and applying in data processing or on-line monitoring for tests, social sciences and other engineering sciences. | Luo, Youxin Chen, Mianyun Che, Xiaoyi He, Zheming | 2008 | Journal of Southeast University(English Edition)2008，24，S1： | 2 |
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